A gendered view of computer professionals: preliminary results of a survey

Abstract: The under-representation of women in the computing profession in many parts the western world has received our attention through numerous publications, the noticeable low representation of women at computer science conferences and in the lecture halls. Over the past two decades, the situation had become worse. This paper seeks to add to the dialogue by presenting preliminary findings from a research project conducted in four countries. The aim of this research was to gain an insight into the perceptions future computer professionals hold on the category of employment loosely defined under the term of "a computer professional." One goal was to get insight into whether or not there is a difference between female and mate students regarding their view of computer professionals. Other goals were to determine if there was any difference between female and male students in different parts of the world, as well as who or what most influences the students to undertake their courses in computing

future computer professional perceptions


Car-caravan snaking. 2 Active caravan braking

Abstract: For part 1, see ibid., p.707-22. Founded on the review and results of Part 1, Part 2 contains a description of the virtual design of an active braking system for caravans or other types of trailer, to suppress snaking vibrations, while being simple from a practical viewpoint. The design process and the design itself are explained. The performance is examined by simulations and it is concluded that the system is effective, robust and realizable with modest and available components

car-caravan snaking
active caravan braking
virtual design
trailer
snaking vibrations suppression
dynamics


From information gateway to digital library management system: a case analysis

Abstract: This paper discusses the design, implementation and evolution of the Cornell University Library Gateway using the case analysis method. It diagnoses the Gateway within the conceptual framework of definitions and best practices associated with information gateways, portals, and emerging digital library management systems, in particular the product ENCompass

digital library management system
Cornell University Library Gateway
information gateways
portals
ENCompass
metadata


Survey says! [online world of polls and surveys]

Abstract: Many content managers miss the fundamental interactivity of the Web by not using polls and surveys. Using interactive features-like a poll or quiz-offers your readers an opportunity to become more engaged in your content. Using a survey to gather feedback about your content provides cost-effective data to help make modifications or plot the appropriate course of action. The Web has allowed us to take traditional market research and turn it on its ear. Surveys and polls can be conducted faster and cheaper than with telephone and mail. But if you are running a Web site, should you care about polls and surveys? Do you know the difference between the two in Web-speak?

site owners
polls
surveys
content managers
World Wide Web
site feedback


Edge-colorings with no large polychromatic stars

Abstract: Given a graph G and a positive integer r, let f/sub r/(G) denote the largest number of colors that can be used in a coloring of E(G) such that each vertex is incident to at most r colors. For all positive integers n and r, we determine f/sub r/(K/sub n,n/) exactly and f/sub r/(K/sub n/) within 1. In doing so, we disprove a conjecture by Y. Manoussakis et al. (1996)

edge colorings
polychromatic stars
positive integer
positive integers


The rise and fall and rise again of customer care

Abstract: Taking care of customers has never gone out of style, but as the recession fades, interest is picking up in a significant retooling of the CRM solutions banks have been using. The goal: usable knowledge to help improve service

usable knowledge
customer relationship management
banks


An augmented spatial digital tree algorithm for contact detection in computational mechanics

Abstract: Based on the understanding of existing spatial digital tree-based contact detection approaches, and the alternating digital tree (ADT) algorithm in particular, a more efficient algorithm, termed the augmented spatial digital tree (ASDT) algorithm, is proposed in the present work. The ASDT algorithm adopts a different point representation scheme that uses only the lower comer vertex to represent a (hyper-)rectangle, with the upper comer vertex serving as the augmented information. Consequently, the ASDT algorithm can keep the working space the same as the original n-dimensional space and, in general, a much better balanced tree can be expected. This, together with the introduction of an additional bounding subregion for the rectangles associated with each tree node, makes it possible to significantly reduce the number of node visits in the region search, although each node visit may be slightly more expensive. Three examples arising in computational mechanics are presented to provide an assessment of the performance of the ASDT. The numerical results indicate that the ASDT is, at least, over 3.9 times faster than the ADT

spatial binary tree-based contact detection approaches


The analysis and control of longitudinal vibrations from wave viewpoint

Abstract: The analysis and control of longitudinal vibrations in a rod from feedback wave viewpoint are synthesized. Both collocated and noncollocated feedback wave control strategies are explored. The control design is based on the local properties of wave transmission and reflection in the vicinity of the control force applied area, hence there is no complex closed form solution involved. The controller is designed to achieve various goals, such as absorbing the incoming vibration energy, creating a vibration free zone and eliminating standing waves in the structure. The findings appear to be very useful in practice due to the simplicity in the implementation of the controllers

longitudinal vibration control
feedback waves
noncollocated feedback wave control
collocated feedback wave control
control design
wave transmission
wave reflection
control force
complex closed form solution
standing waves
vibration energy
vibration free zone


CRONE control: principles and extension to time-variant plants with asymptotically constant coefficients

Abstract: The principles of CRONE control, a frequency-domain robust control design methodology based on fractional differentiation, are presented. Continuous time-variant plants with asymptotically constant coefficients are analysed in the frequency domain, through their representation using time-variant frequency responses. A stability theorem for feedback systems including time-variant plants with asymptotically constant coefficients is proposed. Finally, CRONE control is extended to robust control of these plants

CRONE control
time-variant plants
asymptotically constant coefficients
frequency-domain robust control design
fractional differentiation
time-variant frequency responses
stability theorem
feedback systems
robust control
automatic control


The average-case identifiability and controllability of large scale systems

Abstract: Needs for increased product quality, reduced pollution, and reduced energy and material consumption are driving enhanced process integration. This increases the number of manipulated and measured variables required by the control system to achieve its objectives. This paper addresses the question of whether processes tend to become increasingly more difficult to identify and control as the process dimension increases. Tools and results of multivariable statistics are used to show that, under a variety of assumed distributions on the elements, square processes of higher dimension tend to be more difficult to identify and control, whereas the expected controllability and identifiability of nonsquare processes depends on the relative numbers of measured and manipulated variables. These results suggest that the procedure of simplifying the control problem so that only a square process is considered is a poor practice for large scale systems

large scale systems
average-case identifiability
average-case controllability
enhanced process integration
process control
multivariable statistics
high dimension square processes
nonsquare processes
measured variables
manipulated variables
process identification
Monte Carlo simulations
chemical engineering


Towards strong stability of concurrent repetitive processes sharing resources

Abstract: The paper presents a method for design of stability conditions of concurrent, repetitive processes sharing common resources. Steady-state behaviour of the system with m cyclic processes utilising a resource with the mutual exclusion is considered. Based on a recurrent equations framework necessary and sufficient conditions for the existence of maximal performance steady-state are presented. It was shown that if the conditions hold then the m-process system is marginally stable, i.e., a steady-state of the system depends on the perturbations. The problem of finding the relative positions of the processes leading to waiting-free (maximal efficiency) steady-states of the system is formulated as a constraint logic programming problem. An example illustrating the solving of the problem for a 3-process system using object-oriented, constraint logic programming language Oz is presented. A condition sufficient for strong stability of the m-process system is given. When the condition holds then for any initial phases of the processes a waiting-free steady-state will be reached

strong stability
concurrent repetitive processes
common resources
steady-state behaviour
cyclic processes
mutual exclusion
recurrent equations framework
necessary and sufficient conditions
maximal performance steady-state
waiting-free steady-states
constraint logic programming
3-process system
Oz language


Online coverage of the Olympic Games

Abstract: In 1956 a new medium was evolving which helped shape not only the presentation of the Games to a worldwide audience, but created entirely new avenues for marketing and sponsorship which changed the entire economic relevance of the Games. The medium in 1956 was television, and the medium now, of course, is the Internet. Not since 1956 has Olympic coverage been so impacted by the onset of new technology as the current Olympiad has been. But now the IOC finds itself in another set of circumstances not altogether different from 1956

Olympic Games
online coverage
marketing
sponsorship
economic relevance
Olympiad
IOC
online rights
e-broadcast


STEM: Secure Telephony Enabled Middlebox

Abstract: Dynamic applications, including IP telephony, have not seen wide acceptance within enterprises because of problems caused by the existing network infrastructure. Static elements, including firewalls and network address translation devices, are not capable of allowing dynamic applications to operate properly. The Secure Telephony Enabled Middlebox (STEM) architecture is an enhancement of the existing network design to remove the issues surrounding static devices. The architecture incorporates an improved firewall that can interpret and utilize information in the application layer of packets to ensure proper functionality. In addition to allowing dynamic applications to function normally, the STEM architecture also incorporates several detection and response mechanisms for well-known network-based vulnerabilities. This article describes the key components of the architecture with respect to the SIP protocol

Secure Telephony Enabled Middlebox
STEM
IP telephony
network infrastructure
firewalls
network address translation devices
dynamic applications
STEM architecture
network design
static devices
application layer
detection mechanisms
response mechanisms
network-based vulnerabilities
SIP protocol


Center-crossing recurrent neural networks for the evolution of rhythmic behavior

Abstract: A center-crossing recurrent neural network is one in which the null(hyper)surfaces of each neuron intersect at their exact centers of symmetry, ensuring that each neuron's activation function is centered over the range of net inputs that it receives. We demonstrate that relative to a random initial population, seeding the initial population of an evolutionary search with center-crossing networks significantly improves both the frequency and the speed with which high-fitness oscillatory circuits evolve on a simple walking task. The improvement is especially striking at low mutation variances. Our results suggest that seeding with center-crossing networks may often be beneficial, since a wider range of dynamics is more likely to be easily accessible from a population of center-crossing networks than from a population of random networks

center-crossing recurrent neural networks


A new method of regression on latent variables. Application to spectral data

Abstract: Several applications are based on the assessment of a linear model linking a set of variables Y to a set of predictors X. In the presence of strong colinearity among predictors, as in the case with spectral data, several alternative procedures to ordinary least squares (OLS) are proposed, We discuss a new alternative approach which we refer to as regression models through constrained principal components analysis (RM-CPCA). This method basically shares certain common characteristics with PLS regression as the dependent variables play a central role in determining the latent variables to be used as predictors. Unlike PLS, however, the approach discussed leads to straightforward models. This method also bears some similarity to latent root regression analysis (LRR) that was discussed by several authors. Moreover, a tuning parameter that ranges between 0 and 1 is introduced and the family of models thus formed includes several other methods as particular cases


Embeddings of planar graphs that minimize the number of long-face cycles

Abstract: We consider the problem of finding embeddings of planar graphs that minimize the number of long-face cycles. We prove that for any k >or= 4, it is NP-complete to find an embedding that minimizes the number of face cycles of length at least k

embeddings
planar graphs
long-face cycles
NP-complete problem
graph drawing


High-speed CMOS circuits with parallel dynamic logic and speed-enhanced skewed static logic

Abstract: In this paper, we describe parallel dynamic logic (PDL) which exhibits high speed without charge sharing problem. PDL uses only parallel-connected transistors for fast logic evaluation and is a good candidate for high-speed low-voltage operation. It has less back-bias effect compared to other logic styles, which use stacked transistors. Furthermore, PDL needs no signal ordering or tapering. PDL with speed-enhanced skewed static logic renders straightforward logic synthesis without the usual area penalty due to logic duplication. Our experimental results on two 32-bit carry lookahead adders using 0.25- mu m CMOS technology show that PDL with speed-enhanced skewed static (SSS) look reduces the delay over clock-delayed(CD)-domino by 15%-27% and the power-delay product by 20%-37%

high-speed CMOS circuits
parallel dynamic logic
speed-enhanced skewed static logic
parallel-connected transistors
low-voltage operation
logic synthesis
carry lookahead adders
delay
power-delay product
back-bias effect
stacked transistors
32 bit
0.25 micron


On the relationship between parametric variation and state feedback in chaos control

Abstract: In this Letter, we study the popular parametric variation chaos control and state-feedback methodologies in chaos control, and point out for the first time that they are actually equivalent in the sense that there exist diffeomorphisms that can convert one to the other for most smooth chaotic systems. Detailed conversions are worked out for typical discrete chaotic maps (logistic, Henon) and continuous flows (Rossler, Lorenz) for illustration. This unifies the two seemingly different approaches from the physics and the engineering communities on chaos control. This new perspective reveals some new potential applications such as chaos synchronization and normal form analysis from a unified mathematical point of view

parametric variation
chaos control
state-feedback
logistic
Henon map
continuous flows
Rossler system
Lorenz system
diffeomorphisms


Smart collision information processing sensors for fast moving objects

Abstract: In this technical note we survey the area of smart collision information processing sensors. We review the existing technologies to detect collision or overlap between fast moving physical objects or objects in virtual environments, physical environments or a combination of physical and virtual objects. We report developments in the collision detection of fast moving objects at discrete time steps such as two consecutive time frames, as well as continuous time intervals such as in an interframe collision detection system. Our discussion of computational techniques in this paper is limited to convex objects. Techniques exist however to efficiently decompose non-convex objects into convex objects. We also discuss the tracking technologies for objects from the standpoint of collision detection or avoidance

virtual environments
physical environments
collision detection
discrete time steps
consecutive time frames
continuous time intervals
interframe collision detection
nonconvex objects
collision information processing
fast moving objects
air traffic control
smart sensors
military training
high speed machining
convex objects
tracking


Reaching strong consensus in a general network

Abstract: The strong consensus (SC) problem is a variant of the conventional distributed consensus problem (also known as the Byzantine agreement problem). The SC problem requires that the agreed value among fault-free processors be one of the fault-free processor's initial values. Originally, the problem was studied in a fully connected network with malicious faulty processors. In this paper, the SC problem is re-examined in a general network, in which the components (processors and communication links) may be subjected to different faulty types simultaneously (also called the hybrid fault model or mixed faulty types) and the network topology does not have to be fully connected. The proposed protocol can tolerate the maximum number of tolerable faulty components such that each fault-free processor obtains a common value for the SC problem in a general network

strong consensus problem
distributed consensus problem
Byzantine agreement
fault-free processors
fully connected network
hybrid fault model
fault-tolerant distributed system
strong consensus


Chemical production in the superlative [formaldehyde plant process control system and remote I/O system]

Abstract: BASF commissioned the largest formaldehyde production plant in the world, in December 2000, with an annual capacity of 180000 t. The new plant, built to meet the growing demand for formaldehyde, sets new standards. Its size, technology and above all its cost-effectiveness give it a leading position internationally. To maintain such high standards by the automation technology, in addition to the trail-blazing Simatic PCS 7 process control system from Siemens, BASF selected the innovative remote I/O system I.S.1 from R. STAHL Schaltgerate GmbH to record and to output field signals in hazardous areas Zone 1 and 2. This combination completely satisfied all technical requirements and also had the best price-performance ratio of all the solutions. 25 remote I/O field stations were designed and matched to the needs of the formaldehyde plant

formaldehyde production plant construction


Knowledge organisation of product design blackboard systems via graph decomposition

Abstract: Knowledge organisation plays an important role in building a knowledge-based product design blackboard system. Well-organised knowledge sources will facilitate the effectiveness and efficiency of communication and data exchange in a blackboard system. In a previous investigation, an approach for constructing blackboard systems for product design using a non-directed graph decomposition algorithm was proposed. In this paper, the relationship between graph decomposition and the resultant blackboard system is further studied. A case study of a number of hypothetical blackboard systems that comprise different knowledge organisations is provided

knowledge organisation
product design blackboard systems
graph decomposition
knowledge-based product design
data exchange
case study


Run-time data-flow analysis

Abstract: Parallelizing compilers have made great progress in recent years. However, there still remains a gap between the current ability of parallelizing compilers and their final goals. In order to achieve the maximum parallelism, run-time techniques were used in parallelizing compilers during last few years. First, this paper presents a basic run-time privatization method. The definition of run-time dead code is given and its side effect is discussed. To eliminate the imprecision caused by the run-time dead code, backward data-flow information must be used. Proteus Test, which can use backward information in run-time, is then presented to exploit more dynamic parallelism. Also, a variation of Proteus Test, the Advanced Proteus Test, is offered to achieve partial parallelism. Proteus Test was implemented on the parallelizing compiler AFT. In the end of this paper the program fpppp.f of Spec95fp Benchmark is taken as an example, to show the effectiveness of Proteus Test

run-time data flow analysis
parallelizing compilers
run-time privatization method
run-time dead code
backward data-flow information
Proteus Test
dynamic parallelism


Estimating the intrinsic dimension of data with a fractal-based method

Abstract: In this paper, the problem of estimating the intrinsic dimension of a data set is investigated. A fractal-based approach using the Grassberger-Procaccia algorithm is proposed. Since the Grassberger-Procaccia algorithm (1983) performs badly on sets of high dimensionality, an empirical procedure that improves the original algorithm has been developed. The procedure has been tested on data sets of known dimensionality and on time series of Santa Fe competition

data intrinsic dimension estimation
fractal-based method
time series
Santa Fe competition
pattern recognition


Scalable hybrid computation with spikes

Abstract: We outline a hybrid analog-digital scheme for computing with three important features that enable it to scale to systems of large complexity: First, like digital computation, which uses several one-bit precise logical units to collectively compute a precise answer to a computation, the hybrid scheme uses several moderate-precision analog units to collectively compute a precise answer to a computation. Second, frequent discrete signal restoration of the analog information prevents analog noise and offset from degrading the computation. Third, a state machine enables complex computations to be created using a sequence of elementary computations. A natural choice for implementing this hybrid scheme is one based on spikes because spike-count codes are digital, while spike-time codes are analog. We illustrate how spikes afford easy ways to implement all three components of scalable hybrid computation. First, as an important example of distributed analog computation, we show how spikes can create a distributed modular representation of an analog number by implementing digital carry interactions between spiking analog neurons. Second, we show how signal restoration may be performed by recursive spike-count quantization of spike-time codes. Third, we use spikes from an analog dynamical system to trigger state transitions in a digital dynamical system, which reconfigures the analog dynamical system using a binary control vector; such feedback interactions between analog and digital dynamical systems create a hybrid state machine (HSM). The HSM extends and expands the concept of a digital finite-state-machine to the hybrid domain. We present experimental data from a two-neuron HSM on a chip that implements error-correcting analog-to-digital conversion with the concurrent use of spike-time and spike-count codes. We also present experimental data from silicon circuits that implement HSM-based pattern recognition using spike-time synchrony. We outline how HSMs may be used to perform learning, vector quantization, spike pattern recognition and generation, and how they may be reconfigured


In medias res [DVD formats]

Abstract: Four years in the making, the DVD format war rages on, no winner insight. meanwhile, the spoils of war abound, and DVD media manufacturers stand poised to profit

DVD media manufacturers
DVD format war
DVD-RAM
DVD+RW
DVD+R
DVD-RW
DVD-R
compatibility
writable DVD


Algorithmic results for ordered median problems

Abstract: In a series of papers a new type of objective function in location theory, called ordered median function, has been introduced and analyzed. This objective function unifies and generalizes most common objective functions used in location theory. In this paper we identify finite dominating sets for these models and develop polynomial time algorithms together with a detailed complexity analysis

algorithmic results
ordered median problems
objective function
location theory
ordered median function
finite dominating sets
polynomial time algorithms
detailed complexity analysis


Girls, boys, and computers

Abstract: Today North American girls, boys, teachers, and parents frequently regard computer science and programming as something boys are better at. The author considers how many of the factors that contribute to the low participation of women in computing occur first, and perhaps most forcefully, in childhood. She presents four recommendations to address the situation

girls
teachers
computer science
programming
women
childhood
gender issues
boys


Chaotic phenomena and fractional-order dynamics in the trajectory control of redundant manipulators

Abstract: Redundant manipulators have some advantages when compared with classical arms because they allow the trajectory optimization, both on the free space and on the presence of obstacles, and the resolution of singularities. For this type of arms the proposed kinematic control algorithms adopt generalized inverse matrices but, in general, the corresponding trajectory planning schemes show important limitations. Motivated by these problems this paper studies the chaos revealed by the pseudoinverse-based trajectory planning algorithms, using the theory of fractional calculus

chaotic phenomena
fractional-order dynamics
trajectory control
redundant manipulators
classical arms
trajectory optimization
kinematic control algorithms
generalized inverse matrices
trajectory planning schemes
fractional calculus


Conditions for decentralized integral controllability

Abstract: The term decentralized integral controllability (DIC) pertains to the existence of stable decentralized controllers with integral action that have closed-loop properties such as stable independent detuning. It is especially useful to select control structures systematically at the early stage of control system design because the only information needed for DIC is the steady-state process gain matrix. Here, a necessary and sufficient condition conjectured in the literature is proved. The real structured singular value which can exploit realness of the controller gain is used to describe computable conditions for DIC. The primary usage of DIC is to eliminate unworkable pairings. For this, two other simple necessary conditions are proposed. Examples are given to illustrate the effectiveness of the proposed conditions for DIC

decentralized integral controllability
necessary sufficient conditions
stable decentralized controllers
integral action
closed-loop properties
stable independent detuning
control system design
systematic control structure selection
steady-state process gain matrix
real structured singular value
controller gain realness
unworkable pairing elimination
Schur complement


Assignment of periods and priorities of messages and tasks in distributed control systems

Abstract: Presents a task and message-based scheduling method to guarantee the given end-to-end constraints including precedence constraints, time constraints, and period and priority of task and message. The method is an integrated one considering both tasks executed in each node and messages transmitted via the network and is designed to apply to a general distributed control system that has multiple loops and a single loop has sensor nodes with multiple sensors, actuator nodes with multiple actuators, controller nodes with multiple tasks, and several types of constraints. The assigning method of the optimal period and priority of task and message is proposed, using the presented task and message-based scheduling method

periods assignment
priorities assignment
message-based scheduling method
distributed control systems
task-based scheduling method
end-to-end constraints
precedence constraints
time constraints


Discreteness and relevance: a reply to Roman Poznanski

Abstract: In reply to Poznanski (see ibid., p.435, 2002) on discreteness and relevance, Eliasmith claims that all of the concerns voiced by Poznanski in his reply fail to offer a serious challenge to the idea that continuity is irrelevant to a good understanding of cognitive systems. Eliasmith hopes that it is evident that he does not claim that the process in neural systems is discrete, but rather that a complete characterization of the process can be discrete; these of course are significantly different claims

discreteness
relevance
continuity
cognitive systems
neural systems


A framework for rapid local area modeling for construction automation

Abstract: Rapid 3D positioning and modeling in construction can be used to more effectively plan, visualize, and communicate operations before execution. It can also help to optimize equipment operations, significantly improve safety, and enhance a remote operator's spatial perception of the workspace. A new framework for rapid local area sensing and 3D modeling for better planning and control of construction equipment operation is described and demonstrated. By combining human-assisted graphical workspace modeling with pre-stored Computer-Aided Design (CAD) models and simple sensors (such as single-axis laser rangefinders and remote video cameras), modeling time can be significantly reduced while potentially increasing modeling accuracy


End-user perspectives on the uptake of computer supported cooperative working

Abstract: Researchers in information systems have produced a rich collection of meta-analyses and models to further understanding of factors influencing the uptake of information technologies. In the domain of CSCW, however, these models have largely been neglected, and while there are many case studies, no systematic account of uptake has been produced. We use findings from information systems research to structure a meta-analysis of uptake issues as reported in CSCW case studies, supplemented by a detailed re-examination of one of our own case studies from this perspective. This shows that while there are some factors which seem to be largely specific to CSCW introductions, many of the case study results are very similar to standard IS findings. We conclude by suggesting how the two communities of researchers might build on each other's work, and finally propose activity theory as a means of integrating the two perspectives

computer supported cooperative work
end-user perspectives
information systems
meta-analyses
information technology
CSCW
activity theory


A new architecture for implementing pipelined FIR ADF based on classification of coefficients

Abstract: In this paper, we propose a new method for implementing pipelined finite-impulse response (FIR) adaptive digital filter (ADF), with an aim of reducing the maximum delay of the filtering portion of conventional delayed least mean square (DLMS) pipelined ADF. We achieve a filtering section with a maximum delay of one by simplifying a pre-upsampled and a post-downsampled FIR filter using the concept of classification of coefficients. This reduction is independent of the order of the filter, which is an advantage when the order of the filter is very large, and as a result the method can also be applied to infinite impulse response (IIR) filters. Furthermore, when the proposed method is compared with the transpose ADF, which has a filtering section with zero delay, it is realized that it significantly reduces the maximum delay associated with updating the coefficients of FIR ADF. The effect of this is that, the proposed method exhibits a higher convergence speed in comparison to the transpose FIR ADF

pipelined FIR ADF
coefficient classification
adaptive digital filter
maximum delay
delayed least mean square filter
pre-upsampled filter
post-downsampled filter
convergence speed


Sliding mode control of chaos in the cubic Chua's circuit system

Abstract: In this paper, a sliding mode controller is applied to control the cubic Chua's circuit system. The sliding surface of this paper used is one dimension higher than the traditional surface and guarantees its passage through the initial states of the controlled system. Therefore, using the characteristic of this sliding mode we aim to design a controller that can meet the desired specification and use less control energy by comparing with the result in the current existing literature. The results show that the proposed controller can steer Chua's circuit system to the desired state without the chattering phenomenon and abrupt state change

sliding mode control
chaos
cubic Chua circuit system
sliding surface
chattering
state change
match disturbance
mismatch disturbance


Three-dimensional periodic Voronoi grain models and micromechanical FE-simulations of a two-phase steel

Abstract: A three-dimensional model is proposed for modeling of microstructures. The model is based on the finite element method with periodic boundary conditions. The Voronoi algorithm is used to generate the geometrical model, which has a periodic grain structure that follows the original boundaries of the Voronoi cells. As an application, the model is used to model a two-phase ferrite/pearlite steel. It is shown that periodic cells with only five grains generate representative stress-strain curves

two-phase steel
three-dimensional model
periodic Voronoi grain models
micromechanical FEM simulations
microstructures modeling
periodic boundary conditions
Voronoi algorithm
geometrical model
ferrite-pearlite steel
stress-strain curves
Voronoi tessellation
adaptive mesh generator
quadtree/octree-based algorithm
kinematic constraints
computational time


FLID-DL: congestion control for layered multicast

Abstract: We describe fair layered increase/decrease with dynamic layering (FLID-DL): a new multirate congestion control algorithm for layered multicast sessions. FLID-DL generalizes the receiver-driven layered congestion control protocol (RLC) introduced by Vicisano et al. (Proc. IEEE INFOCOM, San Francisco, CA, , p.996-1003, Mar. 1998)ameliorating the problems associated with large Internet group management protocol (IGMP) leave latencies and abrupt rate increases. Like RLC, FLID-DL, is a scalable, receiver-driven congestion control mechanism in which receivers add layers at sender-initiated synchronization points and leave layers when they experience congestion. FLID-DL congestion control coexists with transmission control protocol (TCP) flows as well as other FLID-DL sessions and supports general rates on the different multicast layers. We demonstrate via simulations that our congestion control scheme exhibits better fairness properties and provides better throughput than previous methods. A key contribution that enables FLID-DL and may be useful elsewhere is dynamic layering (DL), which mitigates the negative impact of long IGMP leave latencies and eliminates the need for probe intervals present in RLC. We use DL to respond to congestion much faster than IGMP leave operations, which have proven to be a bottleneck in practice for prior work


The Information Age interview - Capital One

Abstract: Credit card company Capital One attributes its rapid customer growth to the innovative use of cutting-edge technology. European CIO Catherine Doran talks about the systems that have fuelled that runaway success

credit card company
Capital One
customer growth
cutting-edge technology


Temp IT chief rallies troops [Mori]

Abstract: The appointment of a highly qualified interim IT manager enabled market research company Mori to rapidly restructure its IT department. Now the resulting improvements are allowing it to support an increasing role for technology in the assimilation and analysis of market research

market research company
Mori
interim IT manager


Super high definition image (WHD: Wide/Double HD) transmission system

Abstract: This paper describes a WHD image transmission system constructed from a display projector, CODECs, and a camera system imaging a super high definition image (WHD: Wide/Double HD) corresponding to two screen portions of common high-vision images. This system was developed as a transmission system to communicate with or transmit information giving a reality-enhanced feeling to a remote location by using images of super high definition. In addition, the correction processing for the distortions of images occurring due to the structure of the camera system, an outline of the transmission experiments using the proposed system, and subjective evaluation experiments using WHD images are presented

super high definition image transmission system


Efficient combinational verification using overlapping local BDDs and a hash table

Abstract: We propose a novel methodology that combines local BDDs (binary decision diagrams) with a hash table for very efficient verification of combinational circuits. The main purpose of this technique is to remove the considerable overhead associated with case-by-case verification of internal node pairs in typical internal correspondence based verification methods. Two heuristics based on the number of structural levels of circuitry looked at and the total number of nodes in the BDD manager are used to control the BDD sizes and introduce new cutsets based on already found equivalent nodes. We verify the ISCAS85 benchmark circuits and demonstrate significant speedup over existing methods. We also verify several hard industrial circuits and show our superiority in extracting internal equivalences


Characterization of sheet buckling subjected to controlled boundary constraints

Abstract: A wedge strip test is designed to study the onset and post-buckling behavior of a sheet under various boundary constraints. The device can be easily incorporated into a conventional tensile test machine, and material resistance to buckling is measured as the buckling height versus the in-plane strain state. The design yields different but consistent buckling modes with easy changes of boundary conditions (either clamped or freed) and sample geometry. Experimental results are then used to verify a hybrid approach to buckling prediction, i.e., the combination of the FEM analysis and an energy-based analytical wrinkling criterion. The FEM analysis is used to obtain the stress field and deformed geometry in a complex forming condition, while the analytical solution is to provide the predictions less sensitive to artificial numerical parameters. A good agreement between experimental data and numerical predictions is obtained


Repeated games with lack of information on one side: the dual differential approach

Abstract: We introduce the dual differential game of a repeated game with lack of information on one side as the natural continuous time version of the dual game introduced by De Meyer (1996). A traditional way to study the value of differential games is through discrete time approximations. Here, we follow the opposite approach: We identify the limit value of a repeated game in discrete time as the value of a differential game. Namely, we use the recursive structure for the finitely repeated version of the dual game to construct a differential game for which the upper values of the uniform discretization satisfy precisely the same property. The value of the dual differential game exists and is the unique viscosity solution of a first-order derivative equation with a limit condition. We identify the solution by translating viscosity properties in the primal

repeated games
dual differential game
repeated game
discrete time approximations
limit value
discrete time
viscosity solution
limit condition


Recognition of finite simple groups S/sub 4/(q) by their element orders

Abstract: It is proved that among simple groups S/sub 4/(q) in the class of finite-groups, only the groups S/sub 4/(3/sup n/), where n is an odd number greater than unity, are recognizable by a set of their element orders. It is also shown that simple groups U/sub 3/(9), /sup 3/D/sub 4/(2), G/sub 2/(4), S/sub 6/(3), F/sub 4/(2), and /sup 2/E/sub 6/(2) are recognizable, but L/sub 3/(3) is not

finite simple groups recognition
divisibility relation
element orders


Advancements during the past quarter century in on-line monitoring of motor and generator winding insulation

Abstract: Electrical insulation plays a critical role in the operation of motor and generator rotor and stator windings. Premature failure of the insulation can cost millions of dollars per day. With advancements in electronics, sensors, computers and software, tremendous progress has been made in the past 25 yr which has transformed on-line insulation monitoring from a rarely used and expensive tool, to the point where 50% of large utility generators in North America are now equipped for such monitoring. This review paper outlines the motivation for online monitoring, discusses the transition to today's technology, and describes the variety of methods now in use for rotor winding and stator winding monitoring

generator winding insulation
motor generator winding insulation
winding insulation on-line monitoring
premature insulation failure
electrical insulation
electronics
sensors
computers
software
rotor windings
stator windings
temperature monitoring
condition monitors
tagging compounds
ozone monitoring
PD monitoring
magnetic flux monitoring
partial discharge monitoring
endwinding vibration monitoring


Semantic data broadcast for a mobile environment based on dynamic and adaptive chunking

Abstract: Database broadcast is an effective and scalable approach to disseminate information of high affinity to a large collection of mobile clients. A common problem of existing broadcast approaches is the lack of knowledge for a client to determine if all data items satisfying its query could be obtained from the broadcast. We therefore propose a semantic-based broadcast approach. A semantic descriptor is attached to each broadcast unit, called a data chunk. This semantic descriptor allows a client to determine if a query can be answered entirely based on broadcast items and, if needed, identify the precise definition of the remaining items in the form of a "supplementary" query. Data chunks can be of static or dynamic sizes and organized hierarchically. Their boundary can be determined on-the-fly, adaptive to the nature of client queries. We investigate different ways of organizing the data chunks over a broadcast channel to improve access performance. We introduce the data affinity index metric, which more accurately reflects client-perceived performance. A simulation model is built to evaluate our semantic-based broadcast schemes

mobile databases
mobile computing
semantic data broadcast
mobile clients
semantic descriptor
data chunking
query processing
data affinity index
adaptive chunking
answerability


A model for choosing an electronic reserves system: a pre-implementation study at the library of Long Island University's Brooklyn campus

Abstract: This study explores the nature of electronic reserves (e-reserves) and investigates the possibilities of implementing the e-reserves at the Long Island University/Brooklyn Campus Library (LIU/BCL)

Long Island University Brooklyn Campus Library


Gender, software design, and occupational equity

Abstract: After reviewing the work on gender bias in software design, a model of gender-role influenced achievement choice taken from Eccles (1994) is presented. The paper concludes that (1) though laudable, reduction of gender bias in software design is not the most straightforward way to reduce gender inequity in the choice of computing as a career, (2) the model itself makes more clear some of the ethical issues involved in attempting to achieve gender equity on computing, and (3) efforts to reduce gender inequity in the choice of computing as a career need to be evaluated in the light of this model

gender-role influenced achievement choice model


Numerical approximation of nonlinear BVPs by means of BVMs

Abstract: Boundary Value Methods (BVMs) would seem to be suitable candidates for the solution of nonlinear Boundary Value Problems (BVPs). They have been successfully used for solving linear BVPs together with a mesh selection strategy based on the conditioning of the linear systems. Our aim is to extend this approach so as to use them for the numerical approximation of nonlinear problems. For this reason, we consider the quasi-linearization technique that is an application of the Newton method to the nonlinear differential equation. Consequently, each iteration requires the solution of a linear BVP. In order to guarantee the convergence to the solution of the continuous nonlinear problem, it is necessary to determine how accurately the linear BVPs must be solved. For this goal, suitable stopping criteria on the residual and on the error for each linear BVP are given. Numerical experiments on stiff problems give rather satisfactory results, showing that the experimental code, called TOM, that uses a class of BVMs and the quasi-linearization technique, may be competitive with well known solvers for BVPs

numerical approximation
nonlinear boundary value problems
boundary value methods
mesh selection strategy
quasi-linearization technique
Newton method
nonlinear differential equation
stopping criteria
stiff problems
BVMs


Mobile banking's tough sell

Abstract: Banks are having to put their mobile-commerce projects on hold because the essential technology to make the services usable, in particular GPRS (general packet radio service) hasn't become widely available. It is estimated that by the end of 2002, only 5 per cent of adults will have GPRS phones. This will have a knock-on effect for other technologies such as clickable icons and multimedia messaging. In fact banking via WAP (wireless application protocol) has proved to be a frustrating and time-consuming process for the customer. Financial firms' hopes for higher mobile usage are stymied by the fact that improvements to the systems won't happen as fast as they want and the inadequacies of the system go beyond immature technology. Financial services institutions should not wait for customers to become au fait with their WAP. Instead they should be the ones "driving the traffic"

banking
mobile-commerce
GPRS
wireless application protocol


Look into the future of content management

Abstract: Predictions of consolidation in the Content Management (CM) vendor arena have appeared in nearly every major industry prognosis over the past two years. Gartner Group, for example, recently reiterated its prediction that half the CM vendors in existence in mid-2001 would leave the marketplace by the end of 2002. Analysts consistently advise prospective CM buyers to tread carefully because their vendor may not stick around. But fortunately, the story goes, fewer vendor choices will finally bring greater clarity and sharper differentiators to this otherwise very messy product landscape. In fact, the number of CM vendors continues to rise. Industry growth has come through greater demand among CM buyers, but also expanding product functionality as well as successful partnerships. The marketplace certainly cannot sustain its current breadth of vendors in the long run, yet it remains unclear when and how any serious industry consolidation will occur. In the meantime, evolving business models and feature sets have created just the kind of clearer segmentation and transparent product differences that were supposed to emerge following an industry contraction

content management
enterprise systems
product functionality
partnerships
industry consolidation


LAN-based building maintenance and surveillance robot

Abstract: The building and construction industry is the major industry of Hong Kong as in many developed countries around the world. After the commissioning of a high-rise building or a large estate, substantial manpower, both inside the management centre under a standby manner, as well as surveillance for security purposes around the whole building, is required for daily operation to ensure a quality environment for the occupants. If the surveillance job can be done by robots, the efficiency can be highly enhanced, resulting in a great saving of manpower and the improved safety of the management staff as a by-product. Furthermore, if the robot can retrieve commands from the building management system via a local area network (LAN), further savings in manpower can be achieved in terms of first-line fault attendance by human management staff. This paper describes the development of a robot prototype here in Hong Kong, which can handle some daily routine maintenance works and surveillance responsibilities. The hardware structure of the robot and its on-board devices are described. Real-time images captured by a camera on the robot with pan/tilt/zoom functions can be transmitted back to the central management office via a local area network. The interface between the robot and the building automation system (BAS) of the building is discussed. This is the first key achievement of this project with a strong implication on reducing the number of human staff to manage a modem building. Teleoperation of the robot via the Internet or intranet is also possible, which is the second achievement of this project. Finally, the robot can identify its physical position inside the building by a landmark recognition method based on standard CAD drawings, which is the third achievement of this project. The main goal of this paper is not the description of some groundbreaking technology in robotic development. It is mainly intended to convince building designers and managers to incorporate robotic systems when they are managing modem buildings to save manpower and improve efficiency


Basin configuration of a six-dimensional model of an electric power system

Abstract: As part of an ongoing project on the stability of massively complex electrical power systems, we discuss the global geometric structure of contacts among the basins of attraction of a six-dimensional dynamical system. This system represents a simple model of an electrical power system involving three machines and an infinite bus. Apart from the possible occurrence of attractors representing pathological states, the contacts between the basins have a practical importance, from the point of view of the operation of a real electrical power system. With the aid of a global map of basins, one could hope to design an intervention strategy to boot the power system back into its normal state. Our method involves taking two-dimensional sections of the six-dimensional state space, and then determining the basins directly by numerical simulation from a dense grid of initial conditions. The relations among all the basins are given for a specific numerical example, that is, choosing particular values for the parameters in our model


Coarse-grained reduction and analysis of a network model of cortical response: I. Drifting grating stimuli

Abstract: We present a reduction of a large-scale network model of visual cortex developed by McLaughlin, Shapley, Shelley, and Wielaard. The reduction is from many integrate-and-fire neurons to a spatially coarse-grained system for firing rates of neuronal subpopulations. It accounts explicitly for spatially varying architecture, ordered cortical maps (such as orientation preference) that vary regularly across the cortical layer, and disordered cortical maps (such as spatial phase preference or stochastic input conductances) that may vary widely from cortical neuron to cortical neuron. The result of the reduction is a set of nonlinear spatiotemporal integral equations for "phase-averaged" firing rates of neuronal subpopulations across the model cortex, derived asymptotically from the full model without the addition of any extra phenomological constants. This reduced system is used to study the response of the model to drifting grating stimuli - where it is shown to be useful for numerical investigations that reproduce, at far less computational cost, the salient features of the point-neuron network and for analytical investigations that unveil cortical mechanisms behind the responses observed in the simulations of the large-scale computational model. For example, the reduced equations clearly show (1) phase averaging as the source of the time-invariance of cortico-cortical conductances, (2) the mechanisms in the model for higher firing rates and better orientation selectivity of simple cells which are near pinwheel centers, (3) the effects of the length-scales of cortico-cortical coupling, and (4) the role of noise in improving the contrast invariance of orientation selectivity


New age computing [autonomic computing]

Abstract: Autonomic computing (AC), sometimes called self-managed computing, is the name chosen by IBM to describe the company's new initiative aimed at making computing more reliable and problem-free. It is a response to a growing realization that the problem today with computers is not that they need more speed or have too little memory, but that they crash all too often. This article reviews current initiatives being carried out in the AC field by the IT industry, followed by key challenges which require to be addressed in its development and implementation

autonomic computing
new age computing
AC
self-managed computing
IBM initiative
computing reliability
problem-free computing
computer speed
computer memory
computer crash
IT industry initiatives
AC requirements
AC development
AC implementation
open standards
self-healing computing
adaptive algorithms


Mammogram synthesis using a 3D simulation. I. Breast tissue model and image acquisition simulation

Abstract: A method is proposed for generating synthetic mammograms based upon simulations of breast tissue and the mammographic imaging process. A computer breast model has been designed with a realistic distribution of large and medium scale tissue structures. Parameters controlling the size and placement of simulated structures (adipose compartments and ducts) provide a method for consistently modeling images of the same simulated breast with modified position or acquisition parameters. The mammographic imaging process is simulated using a compression model and a model of the X-ray image acquisition process. The compression model estimates breast deformation using tissue elasticity parameters found in the literature and clinical force values. The synthetic mammograms were generated by a mammogram acquisition model using a monoenergetic parallel beam approximation applied to the synthetically compressed breast phantom


Image reconstruction from fan-beam projections on less than a short scan

Abstract: This work is concerned with 2D image reconstruction from fan-beam projections. It is shown that exact and stable reconstruction of a given region-of-interest in the object does not require all lines passing through the object to be measured. Complete (non-truncated) fan-beam projections provide sufficient information for reconstruction when 'every line passing through the region-of-interest intersects the vertex path in a non-tangential way'. The practical implications of this condition are discussed and a new filtered-backprojection algorithm is derived for reconstruction. Experiments with computer-simulated data are performed to support the mathematical results

fan-beam projections
2D image reconstruction
exact stable reconstruction
region-of-interest
vertex path
filtered-backprojection algorithm
X-ray computed tomography
short-scan condition
Hilbert transform
Radon transform
rebinning formula
convolution
linear interpolation
3D head phantom


Analysis and operation of hybrid active filter for harmonic elimination

Abstract: This paper presents a hybrid active filter topology and its control to suppress the harmonic currents from entering the power source. The adopted hybrid active filter consists of one active filter and one passive filter connected in series. By controlling the equivalent output voltage of active filter, the harmonic currents generated by the nonlinear load are blocked and flowed into the passive filter. The power rating of the converter is reduced compared with the pure active filters to filter the harmonic currents. The harmonic current detecting approach and DC-link voltage regulation are proposed to obtain equivalent voltage of active filter. The effectiveness of the adopted topology and control scheme has been verified by the computer simulation and experimental results in a scaled-down laboratory prototype

hybrid active filter
harmonic elimination
harmonic currents suppression
active filter
passive filter
equivalent output voltage
harmonic currents
nonlinear load
converter power rating reduction
DC-link voltage regulation
active filter equivalent voltage
computer simulation
scaled-down laboratory prototype
voltage source inverter


The web services agenda

Abstract: Even the most battle-scarred of CIOs have become excited at the prospect of what web services can do for their businesses. But there are still some shortcomings to be addressed

web services
transaction support
security


More than the money [software project]

Abstract: Experiences creating budgets for large software projects have taught manufacturers that it is not about the money - it is about what one really needs. Before a company can begin to build a budget for a software. project, it has to have a good understanding of what business issues need to be addressed and what the business objectives are. This step is critical because it defines the business goals, outlines the metrics for success, sets the scope for the project, and defines the criteria for selecting the right software

software projects
manufacturing industry
budgeting
management
software requirements


The changing landscape for multi access portals

Abstract: Discusses the factors that have made life difficult for consumer portal operators in recent years causing them, like others in the telecommunications, media and technology sector, to take a close look at their business models following the dot.com crash and the consequent reassessment of Internet-related project financing by the venture capital community. While the pressure is on to generate income from existing customers and users, portal operators must reach new markets and find realistic revenue streams. This search for real revenues has led to a move towards charging for content, a strategy being pursued by a large number of horizontal portal players, including MSN and Terra Lycos. This trend is particularly noticeable in China, where Chinadotcom operates a mainland portal and plans a range of fee-based services, including electronic mail. The nature of advertising itself is changing, with portals seeking blue-chip sponsorship and marketing deals that span a number of years. Players are struggling to redefine and reinvent themselves as a result of the changing environment and even the term "portal" is believed to be obsolete, partly due to its dot.com crash associations. Multi-access portals are expected to dominate the consumer sector, becoming bigger and better overall than their predecessors and playing a more powerful role in the consumer environment

multi-access portals
consumer portal operators
revenue streams
fee-based services
advertising
blue-chip sponsorship


The Internet, knowledge and the academy

Abstract: As knowledge is released from the bounds of libraries, as research becomes no longer confined to the academy, and education/certification is available, any time/any place, the university and the faculty must redefine themselves. Liberal studies, once the core, and currently eschewed in favor of science and technology, will be reborn in those institutions that can rise above the mundane and embrace an emerging "third culture"

Internet
knowledge
academy
education
certification
university
faculty
liberal studies


The decision procedure for profitability of investment projects using the internal rate of return of single-period projects

Abstract: The internal rate of return (IRR) criterion is often used to evaluate profitability of investment projects. In this paper, we focus on a single-period project which consists of two types of cash flows; an investment at one period and a return at a succeeding period, and a financing at one period and a repayment at a succeeding period. We decompose the given investment project into a series of the single-period projects. From the viewpoint of the single-period project, we point out the applicability issue of the IRR criterion, namely the IRR criterion cannot be applied in which a project is composed of both investment type and financing type. Investigating the properties of a series of the single-period projects, we resolve the applicability issue of the IRR criterion and propose the decision procedure for profitability judgment toward any type of investment project based on the comparison between the IRR and the capital cost. We develop a new algorithm to obtain the value of the project investment rate (PIR) for the given project, which is a function of the capital cost, only using the standard IRR computing routine. This outcome is a theoretical breakthrough to widen the utilization of IRR in practical applications

decision procedure
investment project profitability
internal rate of return
single-period projects
profitability
cash flows
investment project decomposition
IRR criterion
project investment rate
PIR


To classify or not to classify, that is the question?

Abstract: In addressing classification issues, the librarian needs to decide what best suits the purpose and requirements of the user group and the organisation they work in. The author has used the well-established Moys Classification Scheme. This gives the level of detail required for current stock and allows for the incorporation of new material as the firm's specialisations develop. The scheme is widely used in other firms as well as in the local law society library, so it will be familiar to many users

Moys Classification Scheme
law society library


Application of artificial intelligence to search ground-state geometry of clusters

Abstract: We introduce a global optimization procedure, the neural-assisted genetic algorithm (NAGA). It combines the power of an artificial neural network (ANN) with the versatility of the genetic algorithm. This method is suitable to solve optimization problems that depend on some kind of heuristics to limit the search space. If a reasonable amount of data is available, the ANN can "understand" the problem and provide the genetic algorithm with a selected population of elements that will speed up the search for the optimum solution. We tested the method in a search for the ground-state geometry of silicon clusters. We trained the ANN with information about the geometry and energetics of small silicon clusters. Next, the ANN learned how to restrict the configurational space for larger silicon clusters. For Si/sub 10/ and Si/sub 20/, we noticed that the NAGA is at least three times faster than the "pure" genetic algorithm. As the size of the cluster increases, it is expected that the gain in terms of time will increase as well

artificial intelligence
ground-state geometry
atomic clusters
global optimization procedure
neural-assisted genetic algorithm
artificial neural network
population
optimum solution
silicon clusters
Si/sub 10/
Si/sub 20/
cluster size


Simple nonlinear dual-window operator for edge detection

Abstract: We propose a nonlinear edge detection technique based on a two-concentric-circular-window operator. We perform a preliminary selection of edge candidates using a standard gradient and use the dual-window operator to reveal edges as zero-crossing points of a simple difference function depending only on the minimum and maximum values in the two windows. Comparisons with other well-established techniques are reported in terms of visual appearance and computational efficiency. They show that detected edges are surely comparable with Canny's and Laplacian of Gaussian algorithms, with a noteworthy reduction in terms of computational load

nonlinear dual-window operator
edge detection
nonlinear edge detection technique
two-concentric-circular-window operator
standard gradient
dual window operator
zero-crossing points
difference function
minimum values
maximum values
computational efficiency
detected edges
Laplacian algorithms
Gaussian algorithms
Canny's algorithms
computational load
nonlinear processing


Local search with constraint propagation and conflict-based heuristics

Abstract: Search algorithms for solving CSP (Constraint Satisfaction Problems) usually fall into one of two main families: local search algorithms and systematic algorithms. Both families have their advantages. Designing hybrid approaches seems promising since those advantages may be combined into a single approach. In this paper, we present a new hybrid technique. It performs a local search over partial assignments instead of complete assignments, and uses filtering techniques and conflict-based techniques to efficiently guide the search. This new technique benefits from both classical approaches: a priori pruning of the search space from filtering-based search and possible repair of early mistakes from local search. We focus on a specific version of this technique: tabu decision-repair. Experiments done on open-shop scheduling problems show that our approach competes well with the best highly specialized algorithms

search algorithms
CSP
Constraint Satisfaction Problems
local search algorithms
systematic algorithms
partial assignments
filtering techniques
tabu decision-repair


The set of just-in-time management strategies: an assessment of their impact on plant-level productivity and input-factor substitutability using variable cost function estimates

Abstract: Many manufacturers in the automobile industry around the world have adopted the just-in-time (JIT) set of management strategies in an effort to improve productivity, efficiency and product quality. The paper provides empirical evidence that supports the idea that JIT manufacturing environments are, in fact, more productive than their non-JIT counterparts. Plant-level cross-sectional data from auto-parts manufacturing firms are used to estimate variable cost functions for a JIT group as well as for a non-JIT group of plants. Differences in cost function characteristics between the two groups are examined and discussed

just-in-time management strategies
plant-level productivity
input-factor substitutability
variable cost function estimates
automobile industry
JIT
efficiency
product quality
auto-parts manufacturing firms


Access to information for blind and visually impaired clients

Abstract: This article guides I&R providers in establishing effective communication techniques for working with visually impaired consumers. The authors discuss common causes of vision impairment and the functional implications of each and offer information on disability etiquette and effective voice, accessible media and in-person communication. There is an overview of assistive technologies used by people who are visually impaired-to facilitate written and electronic communications as well as low-tech solutions for producing large-print and Braille materials in-house. Providers who implement these communication techniques will be well equipped to serve visually-impaired consumers, and consumers will be more likely to avail themselves of these services when providers make them easily accessible

information access
blind clients
visually impaired clients
information and referral systems
communication techniques
disability etiquette
effective voice
accessible media
in-person communication
assistive technologies
electronic communications
written communications
large-print materials
Braille materials


A unifying co-operative Web caching architecture

Abstract: Network caching of objects has become a standard way of reducing network traffic and latency in the Web. However, Web caches exhibit poor performance with a hit rate of about 30%. A solution to improve this hit rate is to have a group of proxies form co-operation where objects can be cached for later retrieval. A cooperative cache system includes protocols for hierarchical and transversal caching. The drawback of such a system lies in the resulting network load due to the number of messages that need to be exchanged to locate an object. This paper proposes a new co-operative Web caching architecture, which unifies previous methods of Web caching. Performance results shows that the architecture achieve up to 70% co-operative hit rate and accesses the cached object in at most two hops. Moreover, the architecture is scalable with low traffic and database overhead

co-operative Web caching architecture
network caching
network traffic reduction
network latency reduction
co-operative hit rate
cooperative cache system
protocols
hierarchical caching
transversal caching
network load
scalable architecture
low traffic overhead
low database overhead
Web browser
World Wide Web


Implementing: it's all about processes

Abstract: Looks at how the key to successful technology deployment can be found in a set of four basic disciplines

vendor-supplied hardware integration services

vendor-supplied software integration services


Harmless delays in Cohen-Grossberg neural networks

Abstract: Without assuming monotonicity and differentiability of the activation functions and any symmetry of interconnections, we establish some sufficient conditions for the globally asymptotic stability of a unique equilibrium for the Cohen-Grossberg (1983) neural network with multiple delays. Lyapunov functionals and functions combined with the Razumikhin technique are employed. The criteria are all independent of the magnitudes of the delays, and thus the delays under these conditions are harmless

harmless delays
Cohen-Grossberg neural networks
monotonicity
differentiability
activation functions
interconnections
globally asymptotic stability
multiple delays
Lyapunov functionals
Razumikhin technique


Option pricing formulas based on a non-Gaussian stock price model

Abstract: Options are financial instruments that depend on the underlying stock. We explain their non-Gaussian fluctuations using the nonextensive thermodynamics parameter q. A generalized form of the Black-Scholes (BS) partial differential equation (1973) and some closed-form solutions are obtained. The standard BS equation (q = 1) which is used by economists to calculate option prices requires multiple values of the stock volatility (known as the volatility smile). Using q = 1.5 which well models the empirical distribution of returns, we get a good description of option prices using a single volatility

Black-Scholes partial differential equation


Modeling and simulation of adaptive available bit rate voice over asynchronous transfer mode networks

Abstract: This article presents a modeling and simulation methodology to analyze the performance of voice quality when sent over the available bit rate service in asynchronous transfer mode networks. Sources can modify the rate at which they send traffic to the network based on the feedback carried in the resource management cells. This is achieved by changing the encoding level. As the contention increases to network resources-bandwidth in this case-sources start reducing the rate at which they generate and send traffic. The efficiency of the scheme under different scheduling/drop policies and other operating conditions and environments is evaluated using simulation modeling. Furthermore, sensitivity analysis is applied to different parameters, such as queue size and averaging interval length, to investigate their impact on the performance metrics. Results show that limiting the load to 41% of the link capacity results in an acceptable quality

simulation
modeling
performance analysis
voice quality
traffic
feedback
resource management cells
encoding level
bandwidth contention
scheduling/drop policies
queue size
averaging interval length
performance metrics
link capacity
adaptive available bit rate voice
ATM networks


Copyright management in the digital age

Abstract: Listening to and buying music online is becoming increasingly popular with consumers. So much so that Merrill Lynch forecasts the value of the online music market will explode from $8 million in 2001 to $1,409 million in 2005. But online delivery is not without problems; the issue of copyright management in particular has become a serious thorn in the side for digital content creators. Martin Brass, ex- music producer and senior industry consultant at Syntegra, explains

digital age
online music delivery
music industry
Internet
Napster
digital content creators


On average depth of decision trees implementing Boolean functions

Abstract: The article considers the representation of Boolean functions in the form of decision trees. It presents the bounds on average time complexity of decision trees for all classes of Boolean functions that are closed over substitution, and the insertion and deletion of unessential variables. The obtained results are compared with the results developed by M.Ju. Moshkov (1995) that describe the worst case time complexity of decision trees

average depth
decision trees
Boolean functions
average time complexity
worst case time complexity


Schedulability analysis of real-time traffic in WorldFIP networks: an integrated approach

Abstract: The WorldFIP protocol is one of the profiles that constitute the European fieldbus standard EN-50170. It is particularly well suited to be used in distributed computer-controlled systems where a set of process variables must be shared among network devices. To cope with the real-time requirements of such systems, the protocol provides communication services based on the exchange of periodic and aperiodic identified variables. The periodic exchanges have the highest priority and are executed at run time according to a cyclic schedule. Therefore, the respective schedulability can be determined at pre-run-time when building the schedule table. Concerning the aperiodic exchanges, the situation is different since their priority is lower and they are bandied according to a first-come-first-served policy. In this paper, a response-time-based schedulability analysis for the real-time traffic is presented. Such analysis considers both types of traffic in an integrated way, according to their priorities. Furthermore, a fixed-priorities-based policy is also used to schedule the periodic traffic. The proposed analysis represents an improvement relative to previous work and it can be evaluated online as part of a traffic online admission control. This feature is of particular importance when a planning scheduler is used, instead of the typical offline static scheduler, to allow online changes to the set of periodic process variables

real-time traffic schedulability analysis


Integrate-and-fire neurons driven by correlated stochastic input

Abstract: Neurons are sensitive to correlations among synaptic inputs. However, analytical models that explicitly include correlations are hard to solve analytically, so their influence on a neuron's response has been difficult to ascertain. To gain some intuition on this problem, we studied the firing times of two simple integrate-and-fire model neurons driven by a correlated binary variable that represents the total input current. Analytic expressions were obtained for the average firing rate and coefficient of variation (a measure of spike-train variability) as functions of the mean, variance, and correlation time of the stochastic input. The results of computer simulations were in excellent agreement with these expressions. In these models, an increase in correlation time in general produces an increase in both the average firing rate and the variability of the output spike trains. However, the magnitude of the changes depends differentially on the relative values of the input mean and variance: the increase in firing rate is higher when the variance is large relative to the mean, whereas the increase in variability is higher when the variance is relatively small. In addition, the firing rate always tends to a finite limit value as the correlation time increases toward infinity, whereas the coefficient of variation typically diverges. These results suggest that temporal correlations may play a major role in determining the variability as well as the intensity of neuronal spike trains

integrate-and-fire neurons
correlated stochastic input
synaptic input correlations
firing times
correlated binary variable
coefficient of variation
spike-train variability
computer simulation
output spike trains
temporal correlations


Restoration of archival documents using a wavelet technique

Abstract: This paper addresses a problem of restoring handwritten archival documents by recovering their contents from the interfering handwriting on the reverse side caused by the seeping of ink. We present a novel method that works by first matching both sides of a document such that the interfering strokes are mapped with the corresponding strokes originating from the reverse side. This facilitates the identification of the foreground and interfering strokes. A wavelet reconstruction process then iteratively enhances the foreground strokes and smears the interfering strokes so as to strengthen the discriminating capability of an improved Canny edge detector against the interfering strokes. The method has been shown to restore the documents effectively with average precision and recall rates for foreground text extraction at 84 percent and 96 percent, respectively

archival documents restoration
wavelet technique
handwritten archival documents
ink seepage
wavelet reconstruction process
iterative stroke enhancement
Canny edge detector


On bivariate dependence and the convex order

Abstract: We investigate the interplay between variability (in the sense of the convex order) and dependence in a bivariate framework, extending some previous results in this area. We exploit the fact that discrete uniform distributions are dense in the space of probability measures in the topology of weak convergence to prove our central result. We also obtain a partial result in the general multivariate case. Our findings can be interpreted in terms of the impact of component variability on the mean life of correlated serial and parallel systems

bivariate dependence
convex order
discrete uniform distributions
probability measures
topology
weak convergence
component variability
mean life
serial systems
parallel systems
bivariate probability distributions


Record makers [UK health records]

Abstract: Plans for a massive cradle-to-grave electronic records project have been revealed by the government. Is the scheme really viable?

UK health records
electronic records project
integrated care records services
health care
social care


Does classicism explain universality? Arguments against a pure classical component of mind

Abstract: One of the hallmarks of human cognition is the capacity to generalize over arbitrary constituents. Marcus (Cognition 66, p.153; Cognitive Psychology 37, p. 243, 1998) argued that this capacity, called "universal generalization" (universality), is not supported by connectionist models. Instead, universality is best explained by classical symbol systems, with connectionism as its implementation. Here it is argued that universality is also a problem for classicism in that the syntax-sensitive rules that are supposed to provide causal explanations of mental processes are either too strict, precluding possible generalizations; or too lax, providing no information as to the appropriate alternative. Consequently, universality is not explained by a classical theory

classicism
universality
classical component of mind
human cognition
universal generalization
connectionist models
classical symbol systems
syntax-sensitive rules
causal explanations
mental processes


Using fractional order adjustment rules and fractional order reference models in model-reference adaptive control

Abstract: This paper investigates the use of Fractional Order Calculus (FOC) in conventional Model Reference Adaptive Control (MRAC) systems. Two modifications to the conventional MRAC are presented, i.e., the use of fractional order parameter adjustment rule and the employment of fractional order reference model. Through examples, benefits from the use of FOC are illustrated together with some remarks for further research

fractional order adjustment rules
fractional order reference models
model-reference adaptive control
MRAC
FOC
fractional calculus


On M/D/1 queue with deterministic server vacations

Abstract: We study a single server vacation queue with Poisson arrivals, deterministic service of constant duration b (> 0) and deterministic vacations of constant duration d (> 0) and designate this model as M/D/D/1. After completion of each service, the server may take a vacation with probability p or may continue working in the system with probability 1 - p. We obtain time-dependent as well as steady state probability generation functions for the number in the system. For the steady state we obtain explicitly the mean number and the mean waiting time for the system and for the queue. All known results of the M/D/1 queue are derived as a special case. Finally, a numerical illustration is discussed

time-dependent probability generation functions


Cool and green [air conditioning]

Abstract: In these days of global warming, air conditioning engineers need to specify not just for the needs of the occupants, but also to maximise energy efficiency. Julian Brunnock outlines the key areas to consider for energy efficient air conditioning systems


From powder to perfect parts

Abstract: GKN Sinter Metals has increased productivity and quality by automating the powder metal lines that produce its transmission parts

GKN Sinter Metals
powder metal lines
automating
conveyors
gentle transfer units
robotic systems


Autonomous detection of crack initiation using surface-mounted piezotransducers

Abstract: In this paper we report on the application of an in situ health monitoring system, comprising an array of piezoceramic wafer elements, to the detection of fatigue degradation in metallic specimens exposed to cyclic loading. Lamb waves, transmitted through a beam test coupon, are sensed using small surface-mounted piezotransducer elements, and the signals are then autonomously analysed for indications relating to the onset of structural degradation. The experimental results confirm the efficacy of the approach and provide a demonstration of good robustness under realistic loading conditions, emphasizing the great potential for developing an automated in situ structural health monitoring system for application to fatigue-prone operational structures, such as aircraft


Optimal control using the transport equation: the Liouville machine

Abstract: Transport theory describes the scattering behavior of physical particles such as photons. Here we show how to connect this theory to optimal control theory and to adaptive behavior of agents embedded in an environment. Environments and tasks are defined by physical boundary conditions. Given some task, we compute a set of probability densities on continuous state and action and time. From these densities we derive an optimal policy such that for all states the most likely action maximizes the probability of reaching a predefined goal state. Liouville's conservation theorem tells us that the conditional density at time t, state s, and action a must equal the density at t + dt, s + ds, a + da. Discretization yields a linear system that can be solved directly and whose solution corresponds to an optimal policy. Discounted reward schemes are incorporated naturally by taking the Laplace transform of the equations. The Liouville machine quickly solves rather complex maze problems

optimal control
transport equation
Liouville machine
scattering behavior
physical particles
adaptive behavior
embedded agents


Formula-dependent equivalence for compositional CTL model checking

Abstract: We present a polytime computable state equivalence that is defined with respect to a given CTL formula. Since it does not attempt to preserve all CTL formulas, like bisimulation does, we can expect to compute coarser equivalences. This equivalence can be used to reduce the complexity of model checking a system of interacting FSM. Additionally, we show that in some cases our techniques can detect if a formula passes or fails, without forming the entire product machine. The method is exact and fully automatic, and handles full CTL

formula-dependent equivalence
compositional minimization
CTL model checking
polytime computable state equivalence
CTL formula
coarse equivalence
complexity reduction
interacting FSM
automatic method
formal design verification
computation tree logic


How does attitude impact IT implementation: a study of small business owners

Abstract: According to previous studies, attitude towards information technology (IT) among small business owners appears to be a key factor in achieving high quality IT implementations. In an effort to extend this stream of research, we conducted case studies with small business owners and learned that high quality IT implementations resulted with owners who had positive or negative attitudes toward IT, but not with owners who had uncertain attitudes. Owners with apolar attitude, either positive or negative, all took action to temper the uncertainty and risk surrounding the use of new IT in their organization. In contrast, owners with uncertain attitudes did not make mitigating attempts to reduce uncertainty and risk. A consistent finding among those with high quality IT implementations was an entrepreneurial, or shared, management style. It is proposed, based on case study data, that small business owners with an uncertain attitude towards IT might experience higher quality IT results in their organizations through practicing a more entrepreneurial, or shared, management style. The study provides insights for both computer specialists and small business owners planning IT implementations

small business owners
information technology implementation
negative attitudes
positive attitudes
uncertain attitude
risk
organization
management style
computer specialists
planning


Methods for outlier detection in prediction

Abstract: If a prediction sample is different from the calibration samples, it can be considered as an outlier in prediction. In this work, two techniques, the use of uncertainty estimation and the convex hull method are studied to detect such prediction outliers. Classical techniques (Mahalanobis distance and X-residuals), potential functions and robust techniques are used for comparison. It is concluded that the combination of the convex hull method and uncertainty estimation offers a practical way for detecting outliers in prediction. By adding the potential function method, inliers can also be detected

outlier detection
prediction sample
calibration samples
uncertainty estimation
convex hull method
Mahalanobis distance
X-residuals
potential functions
robust techniques
inliers


A mechanism for inferring approximate solutions under incomplete knowledge based on rule similarity

Abstract: This paper proposes an inference method which can obtain an approximate solution even if the knowledge stored in the problem-solving system is incomplete. When a rule needed for solving the problem does not exist, the problem can be solved by using rules similar to the existing rules. In an implementation using the SLD procedure, a resolution is executed between a subgoal and a rule if an atom of the subgoal is similar to the consequence atom of the rule. Similarities between atoms are calculated using a knowledge base of words with account of the reasoning situation, and the reliability of the derived solution is calculated based on these similarities. If many solutions are obtained, they are grouped into classes of similar solutions and a representative solution is then selected for each class. The proposed method was verified experimentally by solving simple problems

inference method
approximate solution
incomplete knowledge
rule similarity
problem solving
SLD procedure
subgoal atom
consequence atom
word knowledge base
reasoning
reliability
representative solution
common sense knowledge


Post-projected Runge-Kutta methods for index-2 differential-algebraic equations

Abstract: A new projection technique for Runge-Kutta methods applied to index-2 differential-algebraic equations is presented in which the numerical approximation is projected only as part of the output process. It is shown that for methods that are strictly stable at infinity, the order of convergence is unaffected compared to standard projected methods. Gauss methods, for which this technique is of special interest when some symmetry is to be preserved, are studied in more detail


An accurate COG defuzzifier design using Lamarckian co-adaptation of learning and evolution

Abstract: This paper proposes a design technique of optimal center of gravity (COG) defuzzifier using the Lamarckian co-adaptation of learning and evolution. The proposed COG defuzzifier is specified by various design parameters such as the centers, widths, and modifiers of MFs. The design parameters are adjusted with the Lamarckian co-adaptation of learning and evolution, where the learning performs a local search of design parameters in an individual COG defuzzifier, but the evolution performs a global search of design parameters among a population of various COG defuzzifiers. This co-adaptation scheme allows to evolve much faster than the non-learning case and gives a higher possibility of finding an optimal solution due to its wider searching capability. An application to the truck backer-upper control problem of the proposed co-adaptive design method of COG defuzzifier is presented. The approximation ability and control performance are compared with those of the conventionally simplified COG defuzzifier in terms of the fuzzy logic controller's approximation error and the average tracing distance, respectively

optimal center of gravity defuzzifier
learning
evolution
fuzzy logic controller
local search


Portal payback

Abstract: The benefits of deploying a corporate portal are well-documented: access to applications and content is centralised, so users do not spend hours searching for information; the management of disparate applications is also centralised, and by allowing users to access 'self-service' applications in areas such as human resources and procurement, organisations spend less time on manual processing tasks. But how far can prospective customers rely on the ROI figures presented to them by portal technology vendors? In particular, how reliable are the 'ROI calculators' these vendors supply on their web sites?

corporate portal
return on investment
ROI calculator
web sites
metrics


A modified Fieller interval for the interval estimation of effective doses for a logistic dose-response curve

Abstract: Interval estimation of the gamma % effective dose ( mu /sub gamma / say) is often based on the asymptotic variance of the maximum likelihood estimator (delta interval) or Fieller's theorem (Fieller interval). Sitter and Wu (1993) compared the delta and Fieller intervals for the median effective dose ( mu /sub 50/) assuming a logistic dose-response curve. Their results indicated that although Fieller intervals are generally superior to delta intervals, they appear to be conservative. Here an adjusted form of the Fieller interval for mu /sub gamma / termed an adjusted Fieller (AF) interval is introduced. A comparison of the AF interval with the delta and Fieller intervals is provided and the properties of these three interval estimation methods are investigated

modified Fieller interval
interval estimation
effective doses
logistic dose-response curve
asymptotic variance
maximum likelihood estimator
delta interval
Fieller's theorem
median effective dose


Estimation of the vanishing point for automatic driving system using a cross ratio

Abstract: This paper proposes a new method to estimate the vanishing point used as the vehicle heading, which is essential in automatic driving systems. The proposed method uses a cross ratio comprised of a ratio of lengths from four collinear points for extracting the edges that shape the vanishing point. Then, lines that intersect at one point are fitted to the edges in a Hough space. Consequently, the vanishing point is estimated robustly even when the lane markings are occluded by other vehicles. In the presence of lane markings, the road boundaries are also estimated at the same time. Experimental results from images of a real road scene show the effectiveness of the proposed method

vanishing point estimation
automatic driving system
cross ratio
automatic driving systems
collinear points
Hough space
lane markings
real road scene


An approach to developing computational supports for reciprocal tutoring

Abstract: This study presents a novel approach to developing computational supports for reciprocal tutoring. Reciprocal tutoring is a collaborative learning activity, where two participants take turns to play the role of a tutor and a tutee. The computational supports include scaffolding tools for the tutor and a computer-simulated virtual participant. The approach, including system architecture, implementations of scaffolding tools for the tutor and of a virtual participant is presented herein. Furthermore, a system for reciprocal tutoring is implemented as an example of the approach

reciprocal tutoring computational support


How much should publishers spend on technology?

Abstract: A study confirms that spending on publishing-specific information technology (IT) resources is growing much faster than IT spending for general business activities, at least among leading publishers in the scientific, technical and medical (STM) market. The survey asked about information technology funding and staffing levels-past, present and future-and also inquired about activities in content management, Web delivery, computer support and customer relationship management. The results provide a starting point for measuring information technology growth and budget allocations in this publishing segment

IT spending
content management
Web delivery
publishing
budget
computer support
customer relationship management


Continuous-time linear systems: folklore and fact

Abstract: We consider a family of continuous input-output maps representing linear time-invariant systems that take a set of signals into itself. It is shown that this family contains maps whose impulse response is the zero function, but which take certain inputs into nonzero outputs. It is shown also that this family contains members whose input-output properties are not described by their frequency domain response functions, and that the maps considered need not even commute

continuous-time systems
linear systems
continuous input-output maps
time-invariant systems
impulse response
zero function
frequency domain response
commutation
signal processing


A new voltage-vector selection algorithm in direct torque control of induction motor drives

Abstract: AC drives based on direct torque control of induction machines allow high dynamic performance to be obtained with very simple control schemes. The drive behavior, in terms of current, flux and torque ripple, is dependent on the utilised voltage vector selection strategy and the operating conditions. In this paper a new voltage vector selection algorithm, which allows a sensible reduction of the RMS value of the stator current ripple without increasing the average value of the inverter switching frequency and without the need of a PWM pulse generator block is presented Numerical simulations have been carried out to validate the proposed method

voltage-vector selection algorithm
direct torque control
induction motor drives
AC drives
high dynamic performance
torque ripple
voltage vector selection strategy
operating conditions
RMS value
stator current ripple
inverter switching frequency
torque variations
flux variations
4-poles induction motor
steady-state operation
dynamic behavior
torque step response
220 V
50 Hz
4 kW


Recognizing groups G/sub 2/(3/sup n/) by their element orders

Abstract: It is proved that a finite group that is isomorphic to a simple non-Abelian group G = G/sub 2/(3/sup n/) is, up to isomorphism, recognized by a set omega (G) of its element orders, that is, H approximately= G if omega (H) = omega (G) for some finite group H


An effective feedback control mechanism for DiffServ architecture

Abstract: As a scalable QoS (Quality of Service) architecture, Diffserv (Differentiated Service) mainly consists of two components: traffic conditioning at the edge of the Diffserv domain and simple packet forwarding inside the DiffServ domain. DiffServ has many advantages such as flexibility, scalability and simplicity. But when providing AF (Assured Forwarding) services, DiffServ has some problems such as unfairness among aggregated flows or among micro-flows belonging to an aggregated flow. In this paper, a feedback mechanism for AF aggregated flows is proposed to solve this problem. Simulation results show that this mechanism does improve the performance of DiffServ. First, it can improve the fairness among aggregated flows and make DiffServ more friendly toward TCP (Transmission Control Protocol) flows. Second, it can decrease the buffer requirements at the congested router and thus obtain lower delay and packet loss rate. Third, it also keeps almost the same link utility as in normal DiffServ. Finally, it is simple and easy to be implemented

QoS
Diffserv
traffic conditioning
packet forwarding
AF
feedback mechanism
fairness
TCP
feedback control
QoS architecture