Fuzzy non-homogeneous Markov systems

Abstract: In this paper the theory of fuzzy logic and fuzzy reasoning is combined with the theory of Markov systems and the concept of a fuzzy non-homogeneous Markov system is introduced for the first time. This is an effort to deal with the uncertainty introduced in the estimation of the transition probabilities and the input probabilities in Markov systems. The asymptotic behaviour of the fuzzy Markov system and its asymptotic variability is considered and given in closed analytic form. Moreover, the asymptotically attainable structures of the system are estimated also in a closed analytic form under some realistic assumptions. The importance of this result lies in the fact that in most cases the traditional methods for estimating the probabilities can not be used due to lack of data and measurement errors. The introduction of fuzzy logic into Markov systems represents a powerful tool for taking advantage of the symbolic knowledge that the experts of the systems possess

fuzzy nonhomogeneous Markov systems
fuzzy logic
fuzzy reasoning
uncertainty
transition probabilities
input probabilities
asymptotic variability
measurement errors
symbolic knowledge
probability theory


DAML+OIL: an ontology language for the Semantic Web

Abstract: By all measures, the Web is enormous and growing at a staggering rate, which has made it increasingly difficult-and important-for both people and programs to have quick and accurate access to Web information and services. The Semantic Web offers a solution, capturing and exploiting the meaning of terms to transform the Web from a platform that focuses on presenting information, to a platform that focuses on understanding and reasoning with information. To support Semantic Web development, the US Defense Advanced Research Projects Agency launched the DARPA Agent Markup Language (DAML) initiative to fund research in languages, tools, infrastructure, and applications that make Web content more accessible and understandable. Although the US government funds DAML, several organizations-including US and European businesses and universities, and international consortia such as the World Wide Web Consortium-have contributed to work on issues related to DAML's development and deployment. We focus on DAML's current markup language, DAML+OIL, which is a proposed starting point for the W3C's Semantic Web Activity's Ontology Web Language (OWL). We introduce DAML+OIL syntax and usage through a set of examples, drawn from a wine knowledge base used to teach novices how to build ontologies

Semantic Web
DARPA Agent Markup Language
DAML+OIL
Ontology Web Language
syntax
wine knowledge base


Pontryagin maximum principle of optimal control governed by fluid dynamic systems with two point boundary state constraint

Abstract: We study the optimal control problem subject to the semilinear equation with a state constraint. We prove certain theorems and give examples of state constraints so that the maximum principle holds. The main difficulty of the problem is to make the sensitivity analysis of the state with respect to the control caused by the unboundedness and nonlinearity of an operator

Pontryagin maximum principle
optimal control
fluid dynamics
semilinear equation
state constraints


Solving the multiple competitive facilities location problem

Abstract: In this paper we propose five heuristic procedures for the solution of the multiple competitive facilities location problem. A franchise of several facilities is to be located in a trade area where competing facilities already exist. The objective is to maximize the market share captured by the franchise as a whole. We perform extensive computational tests and conclude that a two-step heuristic procedure combining simulated annealing and an ascent algorithm provides the best solutions


An experimental evaluation of comprehensibility aspects of knowledge structures derived through induction techniques: a case study of industrial fault diagnosis

Abstract: Machine induction has been extensively used in order to develop knowledge bases for decision support systems and predictive systems. The extent to which developers and domain experts can comprehend these knowledge structures and gain useful insights into the basis of decision making has become a challenging research issue. This article examines the knowledge structures generated by the C4.5 induction technique in a fault diagnostic task and proposes to use a model of human learning in order to guide the process of making comprehensive the results of machine induction. The model of learning is used to generate hierarchical representations of diagnostic knowledge by adjusting the level of abstraction and varying the goal structures between 'shallow' and 'deep' ones. Comprehensibility is assessed in a global way in an experimental comparison where subjects are required to acquire the knowledge structures and transfer to new tasks. This method of addressing the issue of comprehensibility appears promising especially for machine induction techniques that are rather inflexible with regard to the number and sorts of interventions allowed to system developers

knowledge structure comprehensibility aspects


A review of methodologies used in research on cadastral development

Abstract: World-wide, much attention has been given to cadastral development. As a consequence of experiences made during recent decades, several authors have stated the need for research in the domain of cadastre and proposed methodologies to be used. The paper contributes to the acceptance of research methodologies needed for cadastral development, and thereby enhances theory in the cadastral domain. The paper reviews nine publications on cadastre and identifies the methodologies used. The review focuses on the institutional, social, political and economic aspects of cadastral development, rather than on the technical aspects. The main conclusion is that the methodologies used are largely those of the social sciences. That agrees with the notion that cadastre relates as much to people and institutions, as it relates to land, and that cadastral systems are shaped by social, political and economic conditions, as well as technology. Since the geodetic survey profession has been the keeper of the cadastre, geodetic surveyors will have to deal ever more with social science matters, a fact that universities will have to consider

cadastral development methodologies
cadastre
research methodologies
political aspects
economic aspects
social sciences
economic conditions
geodetic survey profession
geodetic surveyors
land registration
case study


TPTP, CASC and the development of a semantically guided theorem prover

Abstract: The first-order theorem prover SCOTT has been through a series of versions over some ten years. The successive provers, while retaining the same underlying technology, have used radically different algorithms and shown wide differences of behaviour. The development process has depended heavily on experiments with problems from the TPTP library and has been sharpened by participation in CASC each year since 1997. We outline some of the difficulties inherent in designing and refining a theorem prover as complex as SCOTT, and explain our experimental methodology. While SCOTT is not one of the systems which have been highly optimised for CASC, it does help to illustrate the influence of both CASC and the TPTP library on contemporary theorem proving research

TPTP library
Semantically Constrained Otter
proof searches
CASC
semantically guided theorem prover
first-order theorem prover
SCOTT
experimental methodology


On the p-adic Birch, Swinnerton-Dyer Conjecture for non-semistable reduction

Abstract: In this paper, we examine the Iwasawa theory of elliptic curves E with additive reduction at an odd prime p. By extending Perrin-Riou's theory to certain nonsemistable representations, we are able to convert Kato's zeta-elements into p-adic L-functions. This allows us to deduce the cotorsion of the Selmer group over the cyclotomic Z/sub p/-extension of Q, and thus prove an inequality in the p-adic Birch and Swinnerton-Dyer conjecture at primes p whose square divides the conductor of E

p-adic Birch
Swinnerton-Dyer conjecture
nonsemistable reduction
lwasawa theory
elliptic curves
additive reduction
Perrin-Riou's theory
p-adic L-functions
cotorsion
Selmer group
cyclotomic Z/sub p/-extension


Steady-state mean-square error analysis of the cross-correlation and constant modulus algorithm in a MIMO convolutive system

Abstract: The cross-correlation and constant modulus algorithm (CC-CMA) has been proven to be an effective approach in the problem of joint blind equalisation and source separation in a multi-input and multi-output system. In the paper, the steady-state mean-square error performance of CC-CMA in a noise-free environment is studied, and a new expression is derived based on the energy preservation approach of Mai and Sayed (2000). Simulation studies are undertaken to support the analysis

MIMO convolutive system
Steady-state mean-square error analysis
cross-correlation
constant modulus algorithm
joint blind equalisation
source separation
multi-input multi-output system
noise-free environment
energy preservation approach
CC-CMA


P systems with symport/antiport rules: the traces of objects

Abstract: We continue the study of those P systems where the computation is performed by the communication of objects, that is, systems with symport and antiport rules. Instead of the (number of) objects collected in a specified membrane, as the result of a computation we consider the itineraries of a certain object through membranes, during a halting computation, written as a coding of the string of labels of the visited membranes. The family of languages generated in this way is investigated with respect to its place in the Chomsky hierarchy. When the (symport and antiport) rules are applied in a conditional manner, promoted or inhibited by certain objects which should be present in the membrane where a rule is applied, then a characterization of recursively enumerable languages is obtained; the power of systems with the rules applied freely is only partially described

P systems
object communication
object traces
antiport rules
symport rules
itineraries
halting computation
label string coding
languages
Chomsky hierarchy
recursively enumerable languages


John McCarthy: father of AI

Abstract: If John McCarthy, the father of AI, were to coin a new phrase for "artificial intelligence" today, he would probably use "computational intelligence." McCarthy is not just the father of AI, he is also the inventor of the Lisp (list processing) language. The author considers McCarthy's conception of Lisp and discusses McCarthy's recent research that involves elaboration tolerance, creativity by machines, free will of machines, and some improved ways of doing situation calculus

John McCarthy
father of AI
artificial intelligence
computational intelligence
Lisp
list processing
elaboration tolerance
creativity
free will
situation calculus


Two-scale curved element method for elliptic problems with small periodic coefficients

Abstract: This paper is concerned with the second order elliptic problems with small periodic coefficients on a bounded domain with a curved boundary. A two-scale curved element method which couples linear elements and isoparametric elements is proposed. The error estimate is obtained over the given smooth domain. Furthermore an additive Schwarz method is provided for the isoparametric element method

two-scale curved element method
elliptic problems
small periodic coefficients
second order elliptic problems
bounded domain
curved boundary
linear elements
isoparametric elements
error estimate
additive Schwarz method
isoparametric element method


Dueling platforms [healthcare network servers]

Abstract: Many large hospitals and healthcare systems have grown accustomed to the reliability of mainframe architecture, although tighter operating budgets, coupled with advances in client/server technology, have led to more office and clinical applications being moved off mainframes. But Evanston Northwestern Healthcare wasn't ready to get rid of its IBM OS 390 mainframe just yet. While a number of new clinical applications are being installed on two brand new IBM servers, Evanston Northwestern Healthcare will retain its favored hospital billing system and let it reside on the organization's mainframe, as it has since 1982

computerized physician order entry system


Design and modeling of an interval-based ABR flow control protocol

Abstract: A novel flow control protocol is presented for availability bit rate (ABR) service in asynchronous transfer mode (ATM) networks. This scheme features periodic explicit rate feedback that enables precise allocation of link bandwidth and buffer space on a hop-by-hop basis to guarantee maximum throughput, minimum cell loss, and high resource efficiency. With the inclusion of resource management cell synchronization and consolidation algorithms, this protocol is capable of controlling point-to-multipoint ABR services within a unified framework. The authors illustrate the modeling of single ABR connection, the interaction between multiple ABR connections, and the constraints applicable to flow control decisions. A loss-free flow control mechanism is presented for high-speed ABR connections using a fluid traffic model. Supporting algorithms and ATM signaling procedures are specified, in company with linear system modeling, numerical analysis, and simulation results, which demonstrate its performance and cost benefits in high-speed backbone networking scenarios

resource management cell synchronization algorithms

resource management cell consolidation algorithms


Project scheduling under time dependent costs-a branch and bound algorithm

Abstract: In a given project network, execution of each activity in normal duration requires utilization of certain resources. If faster execution of an activity is desired then additional resources at extra cost would be required. Given a project network, the cost structure for each activity and a planning horizon, the project compression problem is concerned with the determination of optimal schedule of performing each activity while satisfying given restrictions and minimizing the total cost of project execution. The paper considers the project compression problem with time dependent cost structure for each activity. The planning horizon is divided into several regular time intervals over which the cost structure of an activity may vary. But the cost structure of the activities remains the same within a time interval. The objective is to find an optimal project schedule minimizing the total project cost. We present a mathematical model for this problem, develop some heuristics and an exact branch and bound algorithm. Using simulated problems we provide an insight into the computational performances of heuristics and the branch and bound algorithm

project scheduling
time dependent costs
branch and bound algorithm
project network
planning horizon
project compression problem
optimal schedule
heuristics


E-learning on the college campus: a help or hindrance to students learning objectives: a case study

Abstract: If you know how to surf the World Wide Web, have used email before, and can learn how to send an email attachment, then learning how to interact in an online course should not be difficult at all. In a way to find out, I decided to offer two identical courses, one of which would be offered online and the other the "traditional way". I wanted to see how students would fare with identical material provided in each course. I wanted their anonymous feedback, when the course was over

distance education
William Paterson University
e-learning


Nurturing clients' trust to encourage engagement success during the customization of ERP systems

Abstract: Customization is a crucial, lengthy, and costly aspect in the successful implementation of ERP systems, and has, accordingly, become a major specialty of many vendors and consulting companies. The study examines how such companies can increase their clients' perception of engagement success through increased client trust that is brought about through responsive and dependable customization. Survey data from ERP customization clients show that, as hypothesized, clients' trust influenced their perception of engagement success with the company. The data also show that clients' trust in the customization company was increased when the company behaved in accordance with client expectations by being responsive, and decreased when the company behaved in a manner that contradicted these expectations by not being dependable. Responses to an open-ended question addendum attached to the survey corroborated the importance of responsiveness and dependability. Implications for customization companies and research on trust are discussed

client trust
engagement success
customization
ERP systems
enterprise resource planning systems
vendors
consulting companies
perceived responsiveness
MRP II implementation
integrity
benevolence
dependability


Records role in e-business

Abstract: Records management standards are now playing a key role in e-business strategy


Improved approximation of Max-Cut on graphs of bounded degree

Abstract: Let alpha approximately=0.87856 denote the best approximation ratio currently known for the Max-Cut problem on general graphs. We consider a semidefinite relaxation of the Max-Cut problem, round it using the random hyperplane rounding technique of M.X. Goemans and D.P. Williamson (1995), and then add a local improvement step. We show that for graphs of degree at most Delta , our algorithm achieves an approximation ratio of at least alpha + epsilon , where epsilon >0 is a constant that depends only on Delta .. Using computer assisted analysis, we show that for graphs of maximal degree 3 our algorithm obtains an approximation ratio of at least 0.921, and for 3-regular graphs the approximation ratio is at least 0.924. We note that for the semidefinite relaxation of Max-Cut used by Goemans and Williamson the integrality gap is at least 1/0.885, even for 2-regular graphs

Max-Cut approximation
semidefinite relaxation
approximation ratio
computer assisted analysis
2-regular graphs
bounded degree graph
best approximation ratio


Reconstruction of time-varying 3-D left-ventricular shape from multiview X-ray cineangiocardiograms

Abstract: This paper reports on the clinical application of a system for recovering the time-varying three-dimensional (3-D) left-ventricular (LV) shape from multiview X-ray cineangiocardiograms. Considering that X-ray cineangiocardiography is still commonly employed in clinical cardiology and computational costs for 3-D recovery and visualization are rapidly decreasing, it is meaningful to develop a clinically applicable system for 3-D LV shape recovery from X-ray cineangiocardiograms. The system is based on a previously reported closed-surface method of shape recovery from two-dimensional occluding contours with multiple views. To apply the method to "real" LV cineangiocardiograms, user-interactive systems were implemented for preprocessing, including detection of LV contours, calibration of the imaging geometry, and setting of the LV model coordinate system. The results for three real LV angiographic image sequences are presented, two with fixed multiple views (using supplementary angiography) and one with rotating views. 3-D reconstructions utilizing different numbers of views were compared and evaluated in terms of contours manually traced by an experienced radiologist. The performance of the preprocesses was also evaluated, and the effects of variations in user-specified parameters on the final 3-D reconstruction results were shown to be sufficiently small. These experimental results demonstrate the potential usefulness of combining multiple views for 3-D recovery from "real" LV cineangiocardiograms

time-varying 3-D left-ventricular shape reconstruction


On a general constitutive description for the inelastic and failure behavior of fibrous laminates. II. Laminate theory and applications

Abstract: For pt. I see ibid., pp. 1159-76. The two papers report systematically a constitutive description for the inelastic and strength behavior of laminated composites reinforced with various fiber preforms. The constitutive relationship is established micromechanically, through layer-by-layer analysis. Namely, only the properties of the constituent fiber and matrix materials of the composites are required as input data. In the previous part lamina theory was presented. Three fundamental quantities of the laminae, i.e. the internal stresses generated in the constituent fiber and matrix materials and the instantaneous compliance matrix, with different fiber preform (including woven, braided, and knitted fabric) reinforcements were explicitly obtained by virtue of the bridging micromechanics model. In this paper, the laminate stress analysis is shown. The purpose of this analysis is to determine the load shared by each lamina in the laminate, so that the lamina theory can be applied. Incorporation of the constitutive equations into an FEM software package is illustrated. A number of application examples are given to demonstrate the efficiency of the constitutive theory. The predictions made include: failure envelopes of multidirectional laminates subjected to biaxial in-plane loads, thermomechanical cycling stress-strain curves of a titanium metal matrix composite laminate, S-N curves of multilayer knitted fabric reinforced laminates under tensile fatigue, and bending load-deflection plots and ultimate bending strengths of laminated braided fabric reinforced beams subjected to lateral loads


On trajectory and force tracking control of constrained mobile manipulators with parameter uncertainty

Abstract: Studies the trajectory and force tracking control problem of mobile manipulators subject to holonomic and nonholonomic constraints with unknown inertia parameters. Adaptive controllers are proposed based on a suitable reduced dynamic model, the defined reference signals and the mixed tracking errors. The proposed controllers not only ensure the entire state of the system to asymptotically converge to the desired trajectory but also ensure the constraint force to asymptotically converge to the desired force. A detailed numerical example is presented to illustrate the developed methods

trajectory control
force tracking control
constrained mobile manipulators
parameter uncertainty
holonomic constraints
nonholonomic constraints
adaptive controllers
reduced dynamic model
mixed tracking errors
asymptotic convergence
position control
mobile robots


Decentralized adaptive output feedback stabilization for a class of interconnected systems with unknown bound of uncertainties

Abstract: The problem of adaptive decentralized stabilization for a class of linear time-invarying large-scale systems with nonlinear interconnectivity and uncertainties is discussed. The bounds of uncertainties are assumed to be unknown. For such uncertain dynamic systems, an adaptive decentralized controller is presented. The resulting closed-loop systems are asymptotically stable in theory. Moreover, an adaptive decentralized control scheme is given. The scheme ensures the closed-loop systems exponentially practically stable and can be used in practical engineering. Finally, simulations show that the control scheme is effective

adaptive decentralized stabilization
closed-loop systems
uncertain dynamic systems
robust control
large scale systems


Breast MR imaging with high spectral and spatial resolutions: preliminary experience

Abstract: The authors evaluated magnetic resonance (MR) imaging with high spectral and spatial resolutions (HSSR) of water and fat in breasts of healthy volunteers (n=6) and women with suspicious lesions (n=6). Fat suppression, edge delineation, and image texture were improved on MR images derived from HSSR data compared with those on conventional MR images. HSSR MR imaging data acquired before and after contrast medium injection showed spectrally inhomogeneous changes in the water resonances in small voxels that were not detectable with conventional MR imaging

breast magnetic resonance imaging
high spectral spatial resolutions
healthy volunteers
edge delineation
image texture
magnetic resonance images
magnetic resonance imaging data
contrast medium injection
water resonances
small voxels
women
suspicious lesions
fat suppression


Combining constraint programming and linear programming on an example of bus driver scheduling

Abstract: Provides details of a successful application where the column generation algorithm was used to combine constraint programming and linear programming. In the past, constraint programming and linear programming were considered to be two competing technologies that solved similar types of problems. Both these technologies had their strengths and weaknesses. The paper shows that the two technologies can be combined together to extract the strengths of both these technologies. Details of a real-world application to optimize bus driver duties are given. This system was developed by ILOG for a major software house in Japan using ILOG-Solver and ILOG-CPLEX, constraint programming and linear programming C/C++ libraries

constraint programming
linear programming
bus driver scheduling
column generation algorithm
ILOG
ILOG-Solver
ILOG-CPLEX
C/C++ libraries


Error resilient intra refresh scheme for H.26L stream

Abstract: Recently much attention has been focused on video streaming through IP-based networks. An error resilient RD intra macro-block refresh scheme for H.26L Internet video streaming is introduced. Various channel simulations have proved that this scheme is more effective than those currently adopted in H.26L

H.26L video streaming
Internet
IP-based networks
error resilient scheme
intra macro-block refresh scheme
channel simulations
RD intra refresh scheme
video communication
RDerr scheme
RDall scheme


Knowledge model reuse: therapy decision through specialisation of a generic decision model

Abstract: We present the definition of the therapy decision task and its associated Heuristic Multi-Attribute (HM) solving method, in the form of a KADS-style specification. The goal of the therapy decision task is to identify the ideal therapy, for a given patient, in accordance with a set of objectives of a diverse nature constituting a global therapy-evaluation framework in which considerations such as patient preferences and quality-of-life results are integrated. We give a high-level overview of this task as a specialisation of the generic decision task, and additional decomposition methods for the subtasks involved. These subtasks possess some reflective capabilities for reasoning about self-models, particularly the learning subtask, which incrementally corrects and refines the model used to assess the effects of the therapies. This work illustrates the process of reuse in the framework of AI software development methodologies such as KADS-CommonKADS in order to obtain new (more specialised but still generic) components for the analysis libraries developed in this context. In order to maximise reuse benefits, where possible, the therapy decision task and HM method have been defined in terms of regular components from the earlier-mentioned libraries. To emphasise the importance of using a rigorous approach to the modelling of domain and method ontologies, we make extensive use of the semi-formal object-oriented analysis notation UML, together with its associated constraint language OCL, to illustrate the ontology of the decision method and the corresponding specific one of the therapy decision domain, the latter being a refinement via inheritance of the former

Heuristic Multi-Attribute solving method


A numerical C/sup 1/-shadowing result for retarded functional differential equations

Abstract: This paper gives a numerical C/sup 1/-shadowing between the exact solutions of a functional differential equation and its numerical approximations. The shadowing result is obtained by comparing exact solutions with numerical approximation which do not share the same initial value. Behavior of stable manifolds of functional differential equations under numerics will follow from the shadowing result


Process specialization: defining specialization for state diagrams

Abstract: A precise definition of specialization and inheritance promises to be as useful in organizational process modeling as it is in object modeling. It would help us better understand, maintain, reuse, and generate process models. However, even though object-oriented analysis and design methodologies take full advantage of the object specialization hierarchy, the process specialization hierarchy is not supported in major process representations, such as the state diagram, data flow diagram, and UML representations. Partly underlying this lack of support is an implicit assumption that we can always specialize a process by treating it as "just another object." We argue in this paper that this is not so straightforward as it might seem; we argue that a process-specific approach must be developed. We propose such an approach in the form of a set of transformations which, when applied to a process description, always result in specialization. We illustrate this approach by applying it to the state diagram representation and demonstrate that this approach to process specialization is not only theoretically possible, but shows promise as a method for categorizing and analyzing processes. We point out apparent inconsistencies between our notion of process specialization and existing work on object specialization but show that these inconsistencies are superficial and that the definition we provide is compatible with the traditional notion of specialization

process specialization
state diagrams
inheritance
organizational process modeling
object-oriented analysis
object specialization hierarchy
process representation
object-oriented design


The theory of information reversal

Abstract: The end of the industrial age coincides with the advent of the information society as the next model of social and economic organization, which brings about significant changes in the way modern man conceives work and the social environment. The functional basis of the new model is pivoted upon the effort to formulate the theory on the violent reversal of the basic relationship between man and information, and isolate it as one of the components for the creation of the new electronic reality. The objective of the theory of reversal is to effectively contribute to the formulation of a new definition consideration in regards to the concept of the emerging information society. In order to empirically apply the theory of reversal, we examine a case study based on the example of the digital library

information reversal theory
information society
industrial age
social organization
economic organization
case study
digital library
information systems


Supporting global user profiles through trusted authorities

Abstract: Personalization generally refers to making a Web site more responsive to the unique and individual needs of each user. We argue that for personalization to work effectively, detailed and interoperable user profiles should be globally available for authorized sites, and these profiles should dynamically reflect changes in user interests. Creating user profiles from user click-stream data seems to be an effective way of generating detailed and dynamic user profiles. However, a user profile generated in this way is available only on the computer where the user accesses his browser, and is inaccessible when the same user works on a different computer. On the other hand, integration of the Internet with telecommunication networks has made it possible for the users to connect to the Web with a variety of mobile devices as well as desktops. This requires that user profiles should be available to any desktop or mobile device on the Internet that users choose to work with. In this paper, we address these problems through the concept of "trusted authority". A user agent at the client side that captures the user click stream, dynamically generates a navigational history 'log' file in Extensible Markup Language (XML). This log file is then used to produce 'user profiles' in a resource description framework (RDF). A user's right to privacy is provided through the Platform for Privacy Preferences (P3P) standard. User profiles are uploaded to the trusted authority and served next time the user connects to the Web

Platform for Privacy Preferences standard

globally unique user ID/password identification


Control of integral processes with dead-time. 2. Quantitative analysis

Abstract: For part 1, see ibid., p.285-90, (2002). Several different control schemes for integral processes with dead time resulted in the same disturbance response. It has already been shown that such a response is subideal. Hence, it is necessary to quantitatively analyse the achievable specifications and the robust stability regions. The control parameter can be quantitatively determined with a compromise between the disturbance response and the robustness. Four specifications: (normalised) maximum dynamic error, maximum decay rate, (normalised) control action bound and approximate recovery time are used to characterise the step-disturbance response. It is shown that any attempt to obtain a (normalised) dynamic error less than tau /sub m/ is impossible and a sufficient condition on the (relative) gain-uncertainty bound is square root (3)/2

integral processes
dead-time
quantitative analysis
disturbance response
robust stability regions
robustness
maximum dynamic error
maximum decay rate
control action bound
approximate recovery time
step-disturbance response
sufficient condition
gain-uncertainty bound


Hand-held digital video-camera for eye examination and follow-up

Abstract: We developed a hand-held digital colour video-camera for eye examination in primary care. The device weighed 550 g. It featured a charge-coupled device (CCD) and corrective optics. Both colour video and digital still images could be taken. The video-camera was connected to a PC with software for database storage, image processing and telecommunication. We studied 88 normal subjects (38 male, 50 female), aged 7-62 years. It was not necessary to use mydriatic eye drops for pupillary dilation. Satisfactory digital images of the whole face and the anterior eye were obtained. The optic disc and the central part of the ocular fundus could also be recorded. Image quality of the face and the anterior eye were excellent; image quality of the optic disc and macula were good enough for tele-ophthalmology. Further studies are needed to evaluate the usefulness of the equipment in different clinical conditions

hand-held digital colour video camera
eye examination
primary care
charge-coupled device
corrective optics
digital still images
colour video images
PC
software
database storage
image processing
telecommunication
normal subjects
whole face
anterior eye
optic disc
ocular fundus
image quality
tele-ophthalmology
clinical conditions
follow-up


Linear tense logics of increasing sets

Abstract: We provide an extension of the language of linear tense logic with future and past connectives F and P, respectively, by a modality that quantifies over the points of some set which is assumed to increase in the course of time. In this way we obtain a general framework for modelling growth qualitatively. We develop an appropriate logical system, prove a corresponding completeness and decidability result and discuss the various kinds of flow of time in the new context. We also consider decreasing sets briefly

linear tense logic
future and past connectives
logical system
completeness
decidability
decreasing sets
temporal reasoning


The open-source HCS project

Abstract: Despite the rumors, the HCS II project is not dead. In fact, HCS has been licensed and is now an open-source project. In this article, the author brings us up to speed on the HCS II project's past, present, and future. The HCS II is an expandable, standalone, network-based (RS-485), intelligent-node, industrial-oriented supervisory control (SC) system intended for demanding home control applications. The HCS incorporates direct and remote digital inputs and outputs, direct and remote analog inputs and outputs, real time or Boolean decision event triggering, X10 transmission and reception, infrared remote control transmission and reception, remote LCDs, and a master console. Its program is compiled on a PC with the XPRESS compiler and then downloaded to the SC where it runs independently of the PC

HCS II
supervisory control system
home control
network-based


Ethnography, customers, and negotiated interactions at the airport

Abstract: In the late 1990s, tightly coordinated airline schedules unraveled owing to massive delays resulting from inclement weather, overbooked flights, and airline operational difficulties. As schedules slipped, the delayed departures and late arrivals led to systemwide breakdowns, customers missed their connections, and airline work activities fell further out of sync. In offering possible answers, we emphasize the need to consider the customer as participant, following the human-centered computing model. Our study applied ethnographic methods to understand the airline system domain and the nature of airline delays, and it revealed the deficiencies of the airline production system model of operations. The research insights that led us to shift from a production and marketing system perspective to a customer-as-participant view might appear obvious to some readers. However, we do not know of any airline that designs its operations and technologies around any other model than the production and marketing system view. Our human-centered analysis used ethnographic methods to gather information, offering new insight into airline delays and suggesting effective ways to improve operations reliability

airline production system operations model


Effectiveness of user testing and heuristic evaluation as a function of performance classification

Abstract: For different levels of user performance, different types of information are processed and users will make different types of errors. Based on the error's immediate cause and the information being processed, usability problems can be classified into three categories. They are usability problems associated with skill-based, rule-based and knowledge-based levels of performance. In this paper, a user interface for a Web-based software program was evaluated with two usability evaluation methods, user testing and heuristic evaluation. The experiment discovered that the heuristic evaluation with human factor experts is more effective than user testing in identifying usability problems associated with skill-based and rule-based levels of performance. User testing is more effective than heuristic evaluation in finding usability problems associated with the knowledge-based level of performance. The practical application of this research is also discussed in the paper

user testing
heuristic evaluation
performance classification
user performance
usability
knowledge-based performance levels
skill-based performance levels
user interface
Web-based software
experiment
human factors
rule-based performance levels


Single machine earliness-tardiness scheduling with resource-dependent release dates

Abstract: This paper deals with the single machine earliness and tardiness scheduling problem with a common due date and resource-dependent release dates. It is assumed that the cost of resource consumption of a job is a non-increasing linear function of the job release date, and this function is common for all jobs. The objective is to find a schedule and job release dates that minimize the total resource consumption, and earliness and tardiness penalties. It is shown that the problem is NP-hard in the ordinary sense even if the due date is unrestricted (the number of jobs that can be scheduled before the due date is unrestricted). An exact dynamic programming (DP) algorithm for small and medium size problems is developed. A heuristic algorithm for large-scale problems is also proposed and the results of a computational comparison between heuristic and optimal solutions are discussed

single machine earliness-tardiness scheduling


The design and implementation of VAMPIRE

Abstract: We describe VAMPIRE: a high-performance theorem prover for first-order logic. As our description is mostly targeted to the developers of such systems and specialists in automated reasoning, it focuses on the design of the system and some key implementation features. We also analyze the performance of the prover at CASC-JC

VAMPIRE
high-performance theorem prover
first-order logic
automated reasoning
performance evaluation
CASC-JC
resolution theorem proving


Approximation of pathwidth of outerplanar graphs

Abstract: There exists a polynomial time algorithm to compute the pathwidth of outerplanar graphs, but the large exponent makes this algorithm impractical. In this paper, we give an algorithm that, given a biconnected outerplanar graph G, finds a path decomposition of G of pathwidth at most twice the pathwidth of G plus one. To obtain the result, several relations between the pathwidth of a biconnected outerplanar graph and its dual are established

pathwidth approximation
outerplanar graphs
polynomial time algorithm
biconnected outerplanar graph
path decomposition


L/sub 2/ model reduction and variance reduction

Abstract: We examine certain variance properties of model reduction. The focus is on L/sub 2/ model reduction, but some general results are also presented. These general results can be used to analyze various other model reduction schemes. The models we study are finite impulse response (FIR) and output error (OE) models. We compare the variance of two estimated models. The first one is estimated directly from data and the other one is computed by reducing a high order model, by L/sub 2/ model reduction. In the FIR case we show that it is never better to estimate the model directly from data, compared to estimating it via L/sub 2/ model reduction of a high order FIR model. For OE models we show that the reduced model has the same variance as the directly estimated one if the reduced model class used contains the true system

L/sub 2/ model reduction
variance reduction
finite impulse response models
FIR models
output error models
identification


Non-linear analysis of nearly saturated porous media: theoretical and numerical formulation

Abstract: A formulation for a porous medium saturated with a compressible fluid undergoing large elastic and plastic deformations is presented. A consistent thermodynamic formulation is proposed for the two-phase mixture problem; thus preserving a straightforward and robust numerical scheme. A novel feature is the specification of the fluid compressibility in terms of a volumetric logarithmic strain, which is energy conjugated to the fluid pressure in the entropy inequality. As a result, the entropy inequality is used to separate three different mechanisms representing the response: effective stress response according to Terzaghi in the solid skeleton, fluid pressure response to compressibility of the fluid, and dissipative Darcy flow representing the interaction between the two phases. The paper is concluded with a couple of numerical examples that display the predictive capabilities of the proposed formulation. In particular, we consider results for the kinematically linear theory as compared to the kinematically non-linear theory

nearly saturated porous media
nonlinear analysis
compressible fluid
large elastic deformations
large plastic deformations
consistent thermodynamic formulation
two-phase mixture problem
robust numerical scheme
fluid compressibility
volumetric logarithmic strain
fluid pressure
entropy inequality
effective stress response
solid skeleton
fluid pressure response
dissipative Darcy flow
predictive capabilities
kinematically linear theory
kinematically nonlinear theory


Two-layer model for the formation of states of the hidden Markov chains

Abstract: Procedures for the formation of states of the hidden Markov models are described. Formant amplitudes and frequencies are used as state features. The training strategy is presented that allows one to calculate the parameters of conditional probabilities of the generation of a given formant set by a given hidden state with the help of the maximum likelihood method

hidden Markov models
formant amplitudes
formant frequencies
state features
conditional probabilities
hidden state
maximum likelihood method


Numerical studies of 2D free surface waves with fixed bottom

Abstract: The motion of surface waves under the effect of bottom is a very interesting and challenging phenomenon in the nature. we use boundary integral method to compute and analyze this problem. In the linear analysis, the linearized equations have bounded error increase under some compatible conditions. This contributes to the cancellation of instable Kelvin-Helmholtz terms. Under the effect of bottom, the existence of equations is hard to determine, but given some limitations it proves true. These limitations are that the swing of interfaces should be small enough, and the distance between surface and bottom should be large enough. In order to maintain the stability of computation, some compatible relationship must be satisfied. In the numerical examples, the simulation of standing waves and breaking waves are calculated. And in the case of shallow bottom, we found that the behavior of waves are rather singular

numerical studies
2D free surface waves
boundary integral method
linear analysis
linearized equations
instable Kelvin-Helmholtz terms


Contracting in the days of ebusiness

Abstract: Putting electronic business on a sound foundation-model theoretically as well as technologically-is a central challenge for research as well as commercial development. This paper concentrates on the discovery and negotiation phase of concluding an agreement based on a contract. We present a methodology for moving seamlessly from a many-to-many relationship in the discovery phase to a one-to-one relationship in the contract negotiation phase. Making the content of contracts persistent is achieved by reconstructing contract templates by means of mereologic (logic of the whole-part relation). Possibly nested sub-structures of the contract template are taken as a basis for negotiation in a dialogical way. For the negotiation itself the contract templates are extended by implications (logical) and sequences (topical)

electronic business
discovery phase
contracting
many-to-many relationship
one-to-one relationship
contract negotiation phase
mereologic
contract templates
nested sub-structure
sequences
implications


Breast cancer: effectiveness of computer-aided diagnosis-observer study with independent database of mammograms

Abstract: Evaluates the effectiveness of a computerized classification method as an aid to radiologists reviewing clinical mammograms for which the diagnoses were unknown to both the radiologists and the computer. Six mammographers and six community radiologists participated in an observer study. These 12 radiologists interpreted, with and without the computer aid, 110 cases that were unknown to both the 12 radiologist observers and the trained computer classification scheme. The radiologists' performances in differentiating between benign and malignant masses without and with the computer aid were evaluated with receiver operating characteristic (ROC) analysis. Two-tailed P values were calculated for the Student t test to indicate the statistical significance of the differences in performances with and without the computer aid. When the computer aid was used, the average performance of the 12 radiologists improved, as indicated by an increase in the area under the ROC curve (A/sub z/) from 0.93 to 0.96 (P<.001), by an increase in partial area under the ROC curve (/sub 0.9/0A'/sub z/) from 0.56 to 0.72 (P<.001), and by an increase in sensitivity from 94% to 98% (P=.022). No statistically significant difference in specificity was found between readings with and those without computer aid ( Delta +-0.014; P=.46; 95% Cl: -0.054, 0.026), where Delta is difference in specificity. When we analyzed results from the mammographers and community radiologists as separate groups, a larger improvement was demonstrated for the community radiologists. Computer-aided diagnosis can potentially help radiologists improve their diagnostic accuracy in the task of differentiating between benign and malignant masses seen on mammograms

receiver operating characteristic analysis


New Jersey African American women writers and their publications: a study of identification from written and oral sources

Abstract: This study examines the use of written sources, and personal interviews and informal conversations with individuals from New Jersey's religious, political, and educational community to identify African American women writers in New Jersey and their intellectual output. The focus on recognizing the community as an oral repository of history and then tapping these oral sources for collection development and acquisition purposes is supported by empirical and qualitative evidence. Findings indicate that written sources are so limited that information professionals must rely on oral sources to uncover local writers and their publications


Unlocking the potential of videoconferencing

Abstract: I propose in this paper to show, through a number of case studies, that videoconferencing is user-friendly, cost-effective, time-effective and life-enhancing for people of all ages and abilities and that it requires only a creative and imaginative approach to unlock its potential. I believe that these benefits need not, and should not, be restricted to the education sector. My examples will range from simple storytelling, through accessing international experts, professional development and distance learning in a variety of forms, to the use of videoconferencing for virtual meetings and planning sessions. In some cases, extracts from the reactions and responses of the participants will be included to illustrate the impact of the medium

videoconferencing
benefits
case studies
education


A winning combination [wireless health care]

Abstract: Three years ago, the Institute of Medicine (IOM) reported that medical errors result in at least 44,000 deaths each year-more than deaths from highway accidents, breast cancer or AIDS. That report, and others which placed serious errors as high as 98,000 annually, served as a wake-up call for healthcare providers such as the CareGroup Healthcare System Inc., a Boston-area healthcare network that is the second largest integrated delivery system in the northeastern United States. With annual revenues of $1.2B, CareGroup provides primary care and specialty services to more than 1,000,000 patients. CareGroup combined wireless technology with the Web to create a provider order entry (POE) system designed to reduce the frequency of costly medical mistakes. The POE infrastructure includes InterSystems Corporation's CACHE database, Dell Computer C600 laptops and Cisco Systems' Aironet 350 wireless networks

Cisco Systems Aironet 350 wireless networks


Superconvergence of discontinuous Galerkin method for nonstationary hyperbolic equation

Abstract: For the first order nonstationary hyperbolic equation taking the piecewise linear discontinuous Galerkin solver, we prove that under the uniform rectangular partition, such a discontinuous solver, after postprocessing, can have two and half approximative order which is half order higher than the optimal estimate by P. Lesaint and P. Raviart (1974) under the rectangular partition

superconvergence of discontinuous Galerkin method


One and two facility network design revisited

Abstract: The one facility one commodity network design problem (OFOC) with nonnegative flow costs considers the problem of sending d units of flow from a source to a destination where arc capacity is purchased in batches of C units. The two facility problem (TFOC) is similar, but capacity can be purchased either in batches of C units or one unit. Flow costs are zero. These problems are known to be NP-hard. We describe an exact O(n/sup 3/3/sup n/) algorithm for these problems based on the repeated use of a bipartite matching algorithm. We also present a better lower bound of Omega (n/sup 2k*/) for an earlier Omega (n/sup 2k/) algorithm described in the literature where k = [d/C] and k* = min{k, [(n 2)/2]}. The matching algorithm is faster than this one for k >or= [(n - 2)/2]. Finally, we provide another reformulation of the problem that is quasi integral. This property could be useful in designing a modified version of the simplex method to solve the problem using a sequence of pivots with integer extreme solutions, referred to as the integral simplex method in the literature


A heuristic approach to resource locations in broadband networks

Abstract: In broadband networks, such as ATM, the importance of dynamic migration of data resources is increasing because of its potential to improve performance especially for transaction processing. In environments with migratory data resources, it is necessary to have mechanisms to manage the locations of each data resource. In this paper, we present an algorithm that makes use of system state information and heuristics to manage locations of data resources in a distributed network. In the proposed algorithm, each site maintains information about state of other sites with respect to each data resource of the system and uses it to find: (1) a subset of sites likely to have the requested data resource; and (2) the site where the data resource is to be migrated from the current site. The proposed algorithm enhances its effectiveness by continuously updating system state information stored at each site. It focuses on reducing the overall average time delay needed by the transaction requests to locate and access the migratory data resources. We evaluated the performance of the proposed algorithm and also compared it with one of the existing location management algorithms, by simulation studies under several system parameters such as the frequency of requests generation, frequency of data resource migrations, network topology and scale of network. The experimental results show the effectiveness of the proposed algorithm in all cases

broadband networks
ATM
resource locations
heuristics
distributed network
data resource migrations
network topology


A novel preterm respiratory mechanics active simulator to test the performances of neonatal pulmonary ventilators

Abstract: A patient active simulator is proposed which is capable of reproducing values of the parameters of pulmonary mechanics of healthy newborns and preterm pathological infants. The implemented prototype is able to: (a) let the operator choose the respiratory pattern, times of apnea, episodes of cough, sobs, etc., (b) continuously regulate and control the parameters characterizing the pulmonary system; and, finally, (c) reproduce the attempt of breathing of a preterm infant. Taking into account both the limitation due to the chosen application field and the preliminary autocalibration phase automatically carried out by the proposed device, accuracy and reliability on the order of 1% is estimated. The previously indicated value has to be considered satisfactory in light of the field of application and the small values of the simulated parameters. Finally, the achieved metrological characteristics allow the described neonatal simulator to be adopted as a reference device to test performances of neonatal ventilators and, more specifically, to measure the time elapsed between the occurrence of a potentially dangerous condition to the patient and the activation of the corresponding alarm of the tested ventilator


On the design of gain-scheduled trajectory tracking controllers [AUV application]

Abstract: A new methodology is proposed for the design of trajectory tracking controllers for autonomous vehicles. The design technique builds on gain scheduling control theory. An application is made to the design of a trajectory tracking controller for a prototype autonomous underwater vehicle (AUV). The effectiveness and advantages of the new control laws derived are illustrated in simulation using a full set of non-linear equations of motion of the vehicle

gain-scheduled trajectory tracking controller design


New hub gears up for algorithmic exchange

Abstract: Warwick University in the UK is on the up and up. Sometimes considered a typical 1960s, middle-of-the-road redbrick institution-not known for their distinction the 2001 UK Research Assessment Exercise (RAE) shows its research to be the fifth most highly-rated in the country, with outstanding standards in the sciences. This impressive performance has rightly given Warwick a certain amount of muscle, which it is flexing rather effectively, aided by a snappy approach to making things happen that leaves some older institutions standing. The result is a brand new Centre for Scientific Computing (CSC), launched within a couple of years of its initial conception

Warwick University Centre for Scientific Computing


Development through gaming

Abstract: Mainstream observers commonly underestimate the role of fringe activities in propelling science and technology. Well-known examples are how wars have fostered innovation in areas such as communications, cryptography, medicine and aerospace; and how erotica has been a major factor in pioneering visual media, from the first printed books to photography, cinematography, videotape, or the latest online video streaming. The article aims to be a sampler of a less controversial, but still often underrated, symbiosis between scientific computing and computing for leisure and entertainment

computer games
scientific computing
leisure
entertainment
graphics


Improving supply-chain performance by sharing advance demand information

Abstract: In this paper, we analyze how sharing advance demand information (ADI) can improve supply-chain performance. We consider two types of ADI, aggregated ADI (A-ADI) and detailed ADI (D-ADI). With A-ADI, customers share with manufacturers information about whether they will place an order for some product in the next time period, but do not share information about which product they will order and which of several potential manufacturers will receive the order. With D-ADI, customers additionally share information about which product they will order, but which manufacturer will receive the order remains uncertain. We develop and solve mathematical models of supply chains where ADI is shared. We derive exact expressions and closed-form approximations for expected costs, expected base-stock levels, and variations of the production quantities. We show that both the manufacturer and the customers benefit from sharing ADI, but that sharing ADI increases the bullwhip effect. We also show that under certain conditions it is optimal to collect ADI from either none or all of the customers. We study two supply chains in detail: a supply chain with an arbitrary number of products that have identical demand rates, and a supply chain with two products that have arbitrary demand rates. For these two supply chains, we analyze how the values of A-ADI and D-ADI depend on the characteristics of the supply chain and on the quality of the shared information, and we identify conditions under which sharing A-ADI and D-ADI can significantly reduce cost. Our results can be used by decision makers to analyze the cost savings that can be achieved by sharing ADI and help them to determine if sharing ADI is beneficial for their supply chains

supply-chain performance improvement
advance demand information
aggregated ADI
detailed ADI
information sharing
manufacturing
mathematical models
closed-form approximations
expected costs
expected base-stock levels
production quantity variations
bullwhip effect
arbitrary product number
identical demand rates
arbitrary demand rates
shared information quality
decision makers
cost savings
forecasting


Model checking games for branching time logics

Abstract: This paper defines and examines model checking games for the branching time temporal logic CTL*. The games employ a technique called focus which enriches sets by picking out one distinguished element. This is necessary to avoid ambiguities in the regeneration of temporal operators. The correctness of these games is proved, and optimizations are considered to obtain model checking games for important fragments of CTL*. A game based model checking algorithm that matches the known lower and upper complexity bounds is sketched

model checking games
branching time logics
temporal logic
temporal operators
complexity bounds


Adaptive thinning for bivariate scattered data

Abstract: This paper studies adaptive thinning strategies for approximating a large set of scattered data by piecewise linear functions over triangulated subsets. Our strategies depend on both the locations of the data points in the plane, and the values of the sampled function at these points - adaptive thinning. All our thinning strategies remove data points one by one, so as to minimize an estimate of the error that results by the removal of a point from the current set of points (this estimate is termed "anticipated error"). The thinning process generates subsets of "most significant" points, such that the piecewise linear interpolants over the Delaunay triangulations of these subsets approximate progressively the function values sampled at the original scattered points, and such that the approximation errors are small relative to the number of points in the subsets. We design various methods for computing the anticipated error at reasonable cost, and compare and test the performance of the methods. It is proved that for data sampled from a convex function, with the strategy of convex triangulation, the actual error is minimized by minimizing the best performing measure of anticipated error. It is also shown that for data sampled from certain quadratic polynomials, adaptive thinning is equivalent to thinning which depends only on the locations of the data points - nonadaptive thinning. Based on our numerical tests and comparisons, two practical adaptive thinning algorithms are proposed for thinning large data sets, one which is more accurate and another which is faster

adaptive thinning
scattered data
piecewise linear functions
triangulated subsets
error
Delaunay triangulations
convex function


Modeling and simulating practices, a work method for work systems design

Abstract: Work systems involve people engaging in activities over time-not just with each other, but also with machines, tools, documents, and other artifacts. These activities often produce goods, services, or-as is the case in the work system described in this article-scientific data. Work systems and work practice evolve slowly over time. The integration and use of technology, the distribution and collocation of people, organizational roles and procedures, and the facilities where the work occurs largely determine this evolution

work practice simulation
work practice modeling
work system design method
complex system interactions
human activity
communication
collaboration
teamwork
tool usage
workspace usage
problem solving
learning behavior


Strong completeness of lattice-valued logic

Abstract: This paper shows strong completeness of the system L for lattice valued logic given by S. Titani (1999), in which she formulates a lattice-valued set theory by introducing the logical implication which represents the order relation on the lattice. Syntax and semantics concerned are described and strong completeness is proved

strong completeness
lattice-valued set theory
order relation
semantics
syntax
lattice-valued logic


A linear time algorithm for recognizing regular Boolean functions

Abstract: A positive (or monotone) Boolean function is regular if its variables are naturally ordered, left to fight, by decreasing strength, so that shifting the nonzero component of any true vector to the left always yields another true vector. This paper considers the problem of recognizing whether a positive function f is regular, where f is given by min T(f) (the set of all minimal true vectors of f). We propose a simple linear time (i.e., O(n|min T(f)|)-time) algorithm for it. This improves upon the previous algorithm by J.S. Provan and M.O. Ball (1988) which requires O(n/sup 2/|min T(f)|) time. As a corollary, we also present an O(n(n+|min T(f)|))-time algorithm for the recognition problem of 2-monotonic functions

linear time algorithm
regular Boolean functions
monotone Boolean function
nonzero component
true vector
positive function
2-monotonic functions


The UPS as network management tool

Abstract: Uninterrupted power supplies (UPS), or battery backup systems, once provided a relatively limited, although important, function-continual battery support to connected equipment in the event of a power failure. However, yesterday's "battery in a box" has evolved into a sophisticated network power management tool that can monitor and actively correct many of the problems that might plague a healthy network. This new breed of UPS system provides such features as automatic voltage regulation, generous runtimes and unattended system shutdown, and now also monitors and automatically restarts critical services and operating systems if they lock up or otherwise fail

uninterrupted power supplies
network power management
unattended system shutdown
automatic voltage regulation


The BIOGENES system for knowledge-based bioprocess control

Abstract: The application of knowledge-based control systems in the area of biotechnological processes has become increasingly popular over the past decade. This paper outlines the structure of the advanced knowledge-based part of the BIOGENES Copyright control system for the control of bioprocesses such as the fed-batch Saccharomyces cerevisiae cultivation. First, a brief overview of all the tasks implemented in the knowledge-based level including process data classification, qualitative process state identification and supervisory process control is given. The procedures performing the on-line identification of metabolic states and supervisory process control (setpoint calculation and control strategy selection) are described in more detail. Finally, the performance of the system is discussed using results obtained from a number of experimental cultivation runs in a laboratory unit


Asymptotic normality for the K/sub phi /-divergence goodness-of-fit tests

Abstract: In this paper for a wide class of goodness-of-fit statistics based K/sub phi /-divergences, the asymptotic normality is established under the assumption n/m/sub n/ to a in (0, infinity ), where n denotes sample size and m/sub n/ the number of cells. This result is extended to contiguous alternatives to study asymptotic efficiency


Optimal multi-degree reduction of Bezier curves with constraints of endpoints continuity

Abstract: Given a Bezier curve of degree n, the problem of optimal multi-degree reduction (degree reduction of more than one degree) by a Bezier curve of degree m (m<n-1) with constraints of endpoint continuity is investigated. With respect to L/sub 2/ norm, this paper presents an approximate method (MDR by L/sub 2/) that gives an explicit solution to deal with it. The method has good properties of endpoint interpolation: continuity of any r, s (r, s>or=0) orders can be preserved at two endpoints respectively. The method in the paper performs multi-degree reduction at one time and does not need stepwise computing. When applied to multi-degree reduction with endpoint continuity of any order, the MDR by L/sub 2/ obtains the best least squares approximation. Comparison with another method of multi-degree reduction (MDR by L/sub infinity /), which achieves the nearly best uniform approximation with respect to L/sub infinity / norm, is also given. The approximate effect of the MDR by L/sub 2/ is better than that of the MDR by L/sub infinity /. Explicit approximate error analysis of the multi-degree reduction methods is presented

optimal multi-degree reduction
Bezier curves
endpoint continuity constraints
approximate method
explicit solution
endpoint interpolation
least squares approximation
uniform approximation
explicit approximate error analysis


Exact frequency-domain reconstruction for thermoacoustic tomography. I. Planar geometry

Abstract: We report an exact and fast Fourier-domain reconstruction algorithm for thermoacoustic tomography in a planar configuration assuming thermal confinement and constant acoustic speed. The effects of the finite size of the detector and the finite length of the excitation pulse are explicitly included in the reconstruction algorithm. The algorithm is numerically and experimentally verified. We also demonstrate that the blurring caused by the finite size of the detector surface is the primary limiting factor on the resolution and that it can be compensated for by deconvolution

medical diagnostic imaging
exact frequency-domain reconstruction
planar configuration
thermal confinement
constant acoustic speed
blurring
finite detector surface size
primary limiting factor
deconvolution
resolution limitation
excitation pulse
reconstruction algorithm
thermoacoustic tomography
planar geometry


How airlines and airports recover from schedule perturbations: a survey

Abstract: The explosive growth in air traffic as well as the widespread adoption of Operations Research techniques in airline scheduling has given rise to tight flight schedules at major airports. An undesirable consequence of this is that a minor incident such as a delay in the arrival of a small number of flights can result in a chain reaction of events involving several flights and airports, causing disruption throughout the system. This paper reviews recent literature in the area of recovery from schedule disruptions. First we review how disturbances at a given airport could be handled, including the effects of runways and fixes. Then we study the papers on recovery from airline schedule perturbations, which involve adjustments in flight schedules, aircraft, and crew. The mathematical programming techniques used in ground holding are covered in some detail. We conclude the review with suggestions on how singular perturbation theory could play a role in analyzing disruptions to such highly sensitive schedules as those in the civil aviation industry

air traffic management
schedule perturbation
operations research techniques
airline scheduling
tight flight schedules
airports
schedule disruptions
recovery
disturbance handling
runways
flight schedule adjustments
aircraft adjustments
crew adjustments
mathematical programming techniques
ground holding
singular perturbation theory
civil aviation industry


Rapid Cauer filter design employing new filter model

Abstract: The exact three-dimensional (3D) design of a coaxial Cauer filter employing a new filter model, a 3D field simulator and a circuit simulator, is demonstrated. Only a few iterations between the field simulator and the circuit simulator are necessary to meet a given specification

Cauer filter
filter design
filter model
3D design
coaxial filter
field simulator
circuit simulator
iterations
bandpass filters


Evaluating the best main battle tank using fuzzy decision theory with linguistic criteria evaluation

Abstract: In this paper, experts' opinions are described in linguistic terms which can be expressed in trapezoidal (or triangular) fuzzy numbers. To make the consensus of the experts consistent, we utilize the fuzzy Delphi method to adjust the fuzzy rating of every expert to achieve the consensus condition. For the aggregate of many experts' opinions, we take the operation of fuzzy numbers to get the mean of fuzzy rating, x/sub ij/ and the mean of weight, w/sub .j/. In multi-alternatives and multi-attributes cases, the fuzzy decision matrix X=[x/sub ij/]/sub m*n/ is constructed by means of the fuzzy rating, x/sub ij/. Then, we can derive the aggregate fuzzy numbers by multiplying the fuzzy decision matrix with the corresponding fuzzy attribute weights. The final results become a problem of ranking fuzzy numbers. We also propose an easy procedure of using fuzzy numbers to rank aggregate fuzzy numbers A/sub i/. In this way, we can obtain the best selection for evaluating the system. For practical application, we propose an algorithm for evaluating the best main battle tank by fuzzy decision theory and comparing it with other methods

battle tank evaluation
fuzzy group decision making
fuzzy decision theory
linguistic criteria evaluation
multiple criteria problems
group decision making
subjective-objective backgrounds
trapezoidal fuzzy numbers
triangular fuzzy numbers
fuzzy Delphi method
fuzzy rating
consensus condition
fuzzy number ranking
fuzzy decision matrix
aggregate fuzzy numbers
fuzzy attribute weights


Identification of linear parameter varying models

Abstract: We consider identification of a certain class of discrete-time nonlinear systems known as linear parameter varying system. We assume that inputs, outputs and the scheduling parameters are directly measured, and a form of the functional dependence of the system coefficients on the parameters is known. We show how this identification problem can be reduced to a linear regression, and provide compact formulae for the corresponding least mean square and recursive least-squares algorithms. We derive conditions on persistency of excitation in terms of the inputs and scheduling parameter trajectories when the functional dependence is of polynomial type. These conditions have a natural polynomial interpolation interpretation, and do not require the scheduling parameter trajectories to vary slowly. This method is illustrated with a simulation example using two different parameter trajectories

linear parameter varying models
identification
discrete-time nonlinear systems
scheduling parameters
functional dependence
system coefficients
linear regression
least mean square algorithms
recursive least-squares algorithms
persistency of excitation conditions
scheduling parameter trajectories
polynomial interpolation interpretation
parameter trajectories
time-varying systems


HeLIN pilot mentoring scheme

Abstract: The health care libraries unit coordinates, facilitates, and promotes continuing personal development for all staff in the Health Libraries and Information Network (HeLIN) of the Oxford Deanery (UK). It supports the development of a culture of lifelong learning and recognizes that CPD should help deliver organizational objectives, as well as enabling all staff to expand and fulfill their potential. A major emphasis for 2000 was to investigate ways of improving support for individual learning within the workplace. The group identified a need to build on existing informal support networks in order to provide additional learning opportunities and decided to investigate the feasibility of piloting a mentoring scheme. The objectives of the pilot were to increase understanding and knowledge of mentoring as a tool for CPD; to investigate existing mentoring schemes and their applicability for HeLIN; to develop a pilot mentoring scheme for HeLIN incorporating a program for accreditation of mentors; and to evaluate the scheme and disseminate the results. In order to identify current practice in this area, a literature review was carried out, and colleagues with an interest in or existing knowledge of mentoring schemes were contacted where possible. In the absence of clearly defined appraisal tools, all abstracts were read, and articles that met the following criteria were obtained and distributed to the group for review


CherylAnn Silberer: all about process [accounting technologist]

Abstract: Silberer's company, CompLete, is making a specialty of workflow process analysis

CompLete
workflow process analysis
accounting technologist


Hamiltonian modelling and nonlinear disturbance attenuation control of TCSC for improving power system stability

Abstract: To tackle the obstacle of applying passivity-based control (PBC) to power systems, an affine non-linear system widely existing in power systems is formulated as a standard Hamiltonian system using a pre-feedback method. The port controlled Hamiltonian with dissipation (PCHD) model of a thyristor controlled serial compensator (TCSC) is then established corresponding with a revised Hamiltonian function. Furthermore, employing the modified Hamiltonian function directly as the storage function, a non-linear adaptive L/sub 2/ gain control method is proposed to solve the problem of L/sub 2/ gain disturbance attenuation for this Hamiltonian system with parametric perturbations. Finally, simulation results are presented to verify the validity of the proposed controller

port controlled Hamiltonian with dissipation model

nonlinear adaptive L/sub 2/ gain control method


Portfolio optimization and the random magnet problem

Abstract: Diversification of an investment into independently fluctuating assets reduces its risk. In reality, movements of assets are mutually correlated and therefore knowledge of cross-correlations among asset price movements are of great importance. Our results support the possibility that the problem of finding an investment in stocks which exposes invested funds to a minimum level of risk is analogous to the problem of finding the magnetization of a random magnet. The interactions for this "random magnet problem" are given by the cross-correlation matrix C of stock returns. We find that random matrix theory allows us to make an estimate for C which outperforms the standard estimate in terms of constructing an investment which carries a minimum level of risk

portfolio optimization
fluctuating assets
cross-correlations
price movements
investment
stocks
invested funds
magnetization
cross-correlation matrix
minimum risk level
spin glasses
random magnet problem


Agreeing with automated diagnostic aids: a study of users' concurrence strategies

Abstract: Automated diagnostic aids that are less than perfectly reliable often produce unwarranted levels of disuse by operators. In the present study, users' tendencies to either agree or disagree with automated diagnostic aids were examined under conditions in which: (1) the aids were less than perfectly reliable but aided-diagnosis was still more accurate that unaided diagnosis; and (2) the system was completely opaque, affording users no additional information upon which to base a diagnosis. The results revealed that some users adopted a strategy of always agreeing with the aids, thereby maximizing the number of correct diagnoses made over several trials. Other users, however, adopted a probability-matching strategy in which agreement and disagreement rates matched the rate of correct and incorrect diagnoses of the aids. The probability-matching strategy, therefore, resulted in diagnostic accuracy scores that were lower than was maximally possible. Users who adopted the maximization strategy had higher self-ratings of problem-solving and decision-making skills, were more accurate in estimating aid reliabilities, and were more confident in their diagnosis on trials in which they agreed with the aids. The potential applications of these findings include the design of interface and training solutions that facilitate the adoption of the most effective concurrence strategies by users of automated diagnostic aids

automated diagnostic aids
user concurrence strategy
probability-matching
disagreement rates
maximization
problem-solving
reliability
complex systems
fault diagnosis


The effect of a male-oriented computer gaming culture on careers in the computer industry

Abstract: If careers in the computer industry were viewed, it would be evident that there is a conspicuous gender gap between the number of male and female employees. The same gap can be observed at the college level where males are dominating females as to those who pursue and obtain a degree in computer science. The question that this research paper intends to show is: why are males so dominant when it comes to computer related matters? The author has traced this question back to the computer game. Computer games are a fun medium and provide the means for an individual to become computer literate through the engagement of spatial learning and cognitive processing abilities. Since such games are marketed almost exclusively to males, females have a distinct disadvantage. Males are more computer literate through the playing of computer games, and are provided with an easy lead-in to more advanced utilization of computers such as programming. Females tend to be turned off due to the male stereotypes and marketing associated with games and thus begins the gender gap

careers
computer industry
gender gap
computer science degree
computer games
computer literacy
female employees
spatial learning
cognitive processing
male stereotypes
marketing


Closed-loop model set validation under a stochastic framework

Abstract: Deals with probabilistic model set validation. It is assumed that the dynamics of a multi-input multi-output (MIMO) plant is described by a model set with unstructured uncertainties, and identification experiments are performed in closed loop. A necessary and sufficient condition has been derived for the consistency of the model set with both the stabilizing controller and closed-loop frequency domain experimental data (FDED). In this condition, only the Euclidean norm of a complex vector is involved, and this complex vector depends linearly on both the disturbances and the measurement errors. Based on this condition, an analytic formula has been derived for the sample unfalsified probability (SUP) of the model set. Some of the asymptotic statistical properties of the SUP have also been briefly discussed. A numerical example is included to illustrate the efficiency of the suggested method in model set quality evaluation


Computation of unmeasured third-generation VCT views from measured views

Abstract: We compute unmeasured cone-beam projections from projections measured by a third-generation helical volumetric computed tomography system by solving a characteristic problem for an ultrahyperbolic differential equation [John (1938)]. By working in the Fourier domain, we convert the second-order PDE into a family of first-order ordinary differential equations. A simple first-order integration is used to solve the ODES

unmeasured third-generation VCT views computation


Approximate relaxed descent method for optimal control problems

Abstract: We consider an optimal control problem for systems governed by ordinary differential equations with control constraints. Since no convexity assumptions are made on the data, the problem is reformulated in relaxed form. The relaxed state equation is discretized by the implicit trapezoidal scheme and the relaxed controls are approximated by piecewise constant relaxed controls. We then propose a combined descent and discretization method that generates sequences of discrete relaxed controls and progressively refines the discretization. Since here the adjoint of the discrete state equation is not defined, we use, at each iteration, an approximate derivative of the cost functional defined by discretizing the continuous adjoint equation and the integral involved by appropriate trapezoidal schemes. It is proved that accumulation points of sequences constructed by this method satisfy the strong relaxed necessary conditions for optimality for the continuous problem. Finally, the computed relaxed controls can be easily approximated by piecewise constant classical controls

approximate relaxed descent method
optimal control problems
ordinary differential equations
relaxed state equation discretization
implicit trapezoidal scheme
piecewise constant relaxed controls
relaxed control approximation
discrete relaxed control sequences
discretization refinement
discrete state equation
cost functional approximate derivative
trapezoidal schemes


Chaos theory as a framework for studying information systems

Abstract: This paper introduces chaos theory as a means of studying information systems. It argues that chaos theory, combined with new techniques for discovering patterns in complex quantitative and qualitative evidence, offers a potentially more substantive approach to understand the nature of information systems in a variety of contexts. The paper introduces chaos theory concepts by way of an illustrative research design

chaos theory
information systems
pattern discovery
complex quantitative evidence
qualitative evidence


Extending Kamp's theorem to model time granularity

Abstract: In this paper, a generalization of Kamp's theorem relative to the functional completeness of the until operator is proved. Such a generalization consists in showing the functional completeness of more expressive temporal operators with respect to the extension of the first-order theory of linear orders MFO[<] with an extra binary relational symbol. The result is motivated by the search of a modal language capable of expressing properties and operators suitable to model time granularity in omega -layered temporal structures

Kamp's theorem
functional completeness
until operator
temporal operators
first-order theory
linear orders
binary relational symbol
omega -layered temporal structures
model time granularity


A comparison theorem for the iterative method with the preconditioner (I + S/sub max/)

Abstract: A.D. Gunawardena et al. (1991) have reported the modified Gauss-Seidel method with a preconditioner (I + S). In this article, we propose to use a preconditioner (I + S/sub max/) instead of (I + S). Here, S/sub max/ is constructed by only the largest element at each row of the upper triangular part of A. By using the lemma established by M. Neumann and R.J. Plemmons (1987), we get the comparison theorem for the proposed method. Simple numerical examples are also given

iterative method
preconditioner
modified Gauss-Seidel method
comparison theorem


Making it to the major leagues: career movement between library and archival professions and from small college to large university libraries

Abstract: Issues of career movement and change are examined between library and archival fields and from small colleges to large universities. Issues examined include professional education and training, initial career-planning and placement, continuing education, scouting and mentoring, job market conditions, work experience and personal skills, professional involvement, and professional association self-interest. This examination leads to five observations: 1. It is easier, in terms of career transitions, for a librarian to become an archivist than it is for an archivist to become a librarian; 2. The progression from a small college venue to a large research university is very manageable with the proper planning and experience; 3. At least three of the career elements-professional education, career-planning, and professional association self-interest-in their best moments provide a foundation that enables a future consideration of change between institutional types and professional areas and in their worst moments conspire against the midcareer professional in terms of change; 4. The elements of scouting, continuing education, work experience, and professional involvement offer the greatest assistance in career transitions; 5. The job market is the wildcard that either stymies or stimulates occupational development

career movement
library profession
archival profession
small college library
large university libraries
professional education
training
continuing education
job market
work experience
personal skills
librarian
occupational development
midcareer


Application of normal possibility decision rule to silence

Abstract: The paper presents the way of combining two decision problems concerning a single (or a common) dimension, so that an effective fuzzy decision rule can be obtained. Normality of the possibility distribution is assumed, leading to possibility of fusing the respective functions related to the two decision problems and their characteristics (decisions, states of nature, utility functions, etc.). The approach proposed can be applied in cases when the statement of the problem requires making of more refined distinctions rather than considering simply a bi-criterion or bi-utility two-decision problem

normal possibility decision rule
silence
conflicting objectives
conflicting utilities
cool head
warm heart
decision problems
two-dimensional fuzzy events


Computing the frequency response of systems affinely depending on uncertain parameters

Abstract: The computation of the frequency response of systems depending affinely on uncertain parameters can be reduced to that of all its one-dimensional edge plants while the image of such an edge plant at a fixed frequency is an arc or a line segment in the complex plane. Based on this conclusion, four computational formulas of the maximal and minimal (maxi-mini) magnitudes and phases of an edge plant at a fixed frequency are given. The formulas, besides sharing a simpler form of expression, concretely display how the extrema of the frequency response of the edge plant relate to the typical characteristics of the arc and line segment such as the centre, radius and tangent points of the arc, the distance from the origin to the line segment etc. The direct application of the results is to compute the Bode-, Nichols- and Nyquist-plot collections of the systems which are needed in robustness analysis and design

frequency response
uncertain parameters
affine systems
one-dimensional edge plants
arc
line segment
Bode-plot
Nichols-plot
Nyquist-plot
robustness analysis
robustness design
frequency-domain design methods


Formal verification of human-automation interaction

Abstract: This paper discusses a formal and rigorous approach to the analysis of operator interaction with machines. It addresses the acute problem of detecting design errors in human-machine interaction and focuses on verifying the correctness of the interaction in complex and automated control systems. The paper describes a systematic methodology for evaluating whether the interface provides the necessary information about the machine to enable the operator to perform a specified task successfully and unambiguously. It also addresses the adequacy of information provided to the user via training materials (e.g., user manual) about the machine's behavior. The essentials of the methodology, which can be automated and applied to the verification of large systems, are illustrated by several examples and through a case study of pilot interaction with an autopilot aboard a modern commercial aircraft. The expected application of this methodology is an augmentation and enhancement, by formal verification, of human-automation interfaces

formal verification
human-automation interaction
man-machine interaction
automated control systems
user interface
autopilot
commercial aircraft


The road to perpetual progress [retail inventory management]

Abstract: With annual revenues increasing 17.0% to 20.0% consistently over the last three years and more than 2,500 new stores opened from 1998 through 2001, Dollar General is on the fast track. However, the road to riches could have easily become the road to ruin had the retailer not exerted control over its inventory management

Dollar General
retailer
inventory management


Genetic algorithm for input/output selection in MIMO systems based on controllability and observability indices

Abstract: A time domain optimisation algorithm using a genetic algorithm in conjunction with a linear search scheme has been developed to find the smallest or near-smallest subset of inputs and outputs to control a multi-input-multi-output system. Experimental results have shown that this proposed algorithm has a very fast convergence rate and high computation efficiency

genetic algorithm
input/output selection
MIMO systems
controllability indices
observability indices
time domain optimisation algorithm
linear search scheme
near-smallest subset
smallest subset
multi-input-multi-output system
very fast convergence
high computation efficiency
multivariable control systems


The impact of the product mix on the value of flexibility

Abstract: Product-mix flexibility is one of the major types of manufacturing flexibility, referring to the ability to produce a broad range of products or variants with presumed low changeover costs. The value of such a capability is important to establish for an industrial firm in order to ensure that the flexibility provided will be at the right level and used profitably rather than in excess of market requirements and consequently costly. We use option-pricing theory to analyse the impact of various product-mix issues on the value of flexibility. The real options model we use incorporates multiple products, capacity constraints as well as set-up costs. The issues treated here include the number of products, demand variability, correlation between products, and the relative demand distribution within the product mix. Thus, we are interested in the nature of the input data to analyse its effect on the value of flexibility. We also check the impact at different capacity levels. The results suggest that the value of flexibility (i) increases with an increasing number of products, (ii) decreases with increasing volatility of product demand, (iii) decreases the more positively correlated the demand is, and (iv) reduces for marginal capacity with increasing levels of capacity. Of these, the impact of positively correlated demand seems to be a major issue. However, the joint impact of the number of products and demand correlation showed some non-intuitive results

product-mix flexibility
flexible manufacturing
manufacturing flexibility
low changeover costs
industrial firm
option-pricing theory
real options model
multiple products
capacity constraints
set-up costs
demand variability
product correlation
relative demand distribution
product demand volatility
marginal capacity
positively correlated demand
demand correlation
capital budgeting


Determinantal solutions of solvable chaotic systems

Abstract: It is shown that two solvable chaotic systems, the arithmetic-harmonic mean (ARM) algorithm and the Ulam-von Neumann (UvN) map, have determinantal solutions. An additional formula for certain determinants and Riccati difference equations play a key role in both cases. Two infinite hierarchies of solvable chaotic systems are presented which have determinantal solutions

determinantal solutions
arithmetic-harmonic mean algorithm
solvable chaotic systems
Ulam-von Neumann map
determinants
Riccati difference equations
Chebyshev polynomial


Dependence graphs: dependence within and between groups

Abstract: This paper applies the two-party dependence theory (Castelfranchi, Cesta and Miceli, 1992, in Y. Demazeau and E. Werner (Eds.) Decentralized AI-3, Elsevier, North Holland) to modelling multiagent and group dependence. These have theoretical potentialities for the study of emerging groups and collective structures, and more generally for understanding social and organisational complexity, and practical utility for both social-organisational and agent systems purposes. In the paper, the dependence theory is extended to describe multiagent links, with a special reference to group and collective phenomena, and is proposed as a framework for the study of emerging social structures, such as groups and collectives. In order to do so, we propose to extend the notion of dependence networks (applied to a single agent) to dependence graphs (applied to an agency). In its present version, the dependence theory is argued to provide (a) a theoretical instrument for the study of social complexity, and (b) a computational system for managing the negotiation process in competitive contexts and for monitoring complexity in organisational and other cooperative contexts

dependence graphs
group dependence
two-party dependence theory
multiagent dependence
emerging groups
collective structures
multiagent systems
organisational complexity
social complexity
agent systems
dependence networks


Explicit matrix representation for NURBS curves and surfaces

Abstract: The matrix forms for curves and surfaces were largely promoted in CAD/CAM. In this paper we have presented two matrix representation formulations for arbitrary degree NURBS curves and surfaces explicitly other than recursively. The two approaches are derived from the computation of divided difference and the Marsden identity respectively. The explicit coefficient matrix of B-spline with equally spaced knot and Bezier curves and surfaces can be obtained by these formulae. The coefficient formulae and the coefficient matrix formulae developed in this paper express non-uniform B-spline functions of arbitrary degree in explicit polynomial and matrix forms.. They are useful for the evaluation and the conversion of NURBS curves and surfaces, in CAD/CAM systems

explicit matrix representation
NURBS curves
NURBS surfaces
CAD/CAM
matrix representation formulations
divided difference
Marsden identity
explicit coefficient matrix
B-spline
equally spaced knot
Bezier curves
Bezier surfaces
coefficient formulae
coefficient matrix formulae
nonuniform B-spline functions
explicit polynomial forms
explicit matrix forms


Rate allocation for video transmission over lossy correlated networks

Abstract: A novel rate allocation algorithm for video transmission over lossy networks subject to bursty packet losses is presented. A Gilbert-Elliot model is used at the encoder to drive the selection of coding parameters. Experimental results using the H.26L test model show a significant performance improvement with respect to the assumption of independent packet losses

rate allocation algorithm
video transmission
lossy correlated networks
bursty packet losses
Gilbert-Elliot model
coding parameters
H.26L test model
video coding