A computational model of learned avoidance behavior in a one-way avoidance experiment

Abstract: We present a computational model of learned avoidance behavior in a one-way avoidance experiment. Our model employs the reinforcement learning paradigm and a temporal-difference algorithm to implement both classically conditioned and instrumentally conditioned components. The role of the classically conditioned component is to develop an expectation of future benefit that is a function of the learning system's state and action. Competition among the instrumentally conditioned components determines the overt behavior generated by the learning system. Our model displays, in simulation, the reduced latency of the avoidance behavior during learning with continuing trials and the resistance to extinction of the avoidance response. These results are consistent with experimentally observed animal behavior. Our model extends the traditional two-process learning mechanism of Mowrer (1947) by explicitly defining the mechanisms of proprioceptive feedback, an internal clock, and generalization over the action space


Experimental investigation of active vibration control using neural networks and piezoelectric actuators

Abstract: The use of neural networks for identification and control of smart structures is investigated experimentally. Piezoelectric actuators are employed to suppress the vibrations of a cantilevered plate subject to impulse, sine wave and band-limited white noise disturbances. The neural networks used are multilayer perceptrons trained with error backpropagation. Validation studies show that the identifier predicts the system dynamics accurately. The controller is trained adaptively with the help of the neural identifier. Experimental results demonstrate excellent closed-loop performance and robustness of the neurocontroller

active vibration control
neural networks
piezoelectric actuators
identification
control
smart structures
cantilevered plate
white noise disturbances
multilayer perceptrons
error backpropagation
closed-loop performance
robustness
neurocontroller
vibration suppression


Study of ambiguities inherent to the spectral analysis of Voigt profiles-a modified Simplex approach

Abstract: In pulsed spectrometries, temporal transients are often analyzed directly in the temporal domain, assuming they consist only of purely exponentially decaying sinusoids. When experimental spectra actually consist of Gaussian or Voigt profiles (Gauss-Lorentz profiles), we show that the direct methods may erroneously interpret such lines as the sum of two or more Lorentzian profiles. Using a Nelder and Mead Simplex method, modified by introducing new means to avoid degeneracies and quenchings in secondary minima, we demonstrate that a large number of different solutions can be obtained with equivalent accuracy over the limited acquisition time interval, with final peak parameters devoid of physical or chemical meaning

pulsed spectrometries
temporal transients
spectral analysis
Voigt profiles
Gaussian profiles
Gauss-Lorentz profiles
Nelder and Mead Simplex method
accuracy
limited acquisition time interval
final peak parameters


A three-tier technology training strategy in a dynamic business environment

Abstract: As end-user training becomes increasingly important in today's technology-intensive business environment, progressive companies remain alert to find ways to provide their end users with timely training and resources. This paper describes an innovative training strategy adopted by one midsize organization to provide its end users with adequate, flexible, and responsive training. The paper then compares the three-tier strategy with other models described in technology training literature. Managers who supervise technology end users in organizations comparable to the one in the study may find the three-tier strategy workable and may want to use it in their own training programs to facilitate training and improve end-user skills. Researchers and scholars may find that the idea of three-tier training generates new opportunities for research


Implementation and performance evaluation of a FIFO queue class library for time warp

Abstract: The authors describe the implementation, use, and performance evaluation of a FIFO queue class library by means of a high-performance, easy-to-use interface employed for queuing simulations in parallel discrete simulations based on the time warp method. Various general-purpose simulation libraries and languages have been proposed, and among these some have the advantage of not requiring users to define anything other than the state vector, and not needing awareness of rollback under a platform which performs state control based on copies. However, because the state vectors must be defined as simple data structures without pointers, dynamic data structures such as a FIFO queue cannot be handled directly. Under the proposed class library, both the platform and the user can handle such structures in the same fashion that embedded data structures are handled. In addition, instead of all stored data, just the operational history can be stored and recovered efficiently at an effectively minimal cost by taking advantage of the first-in-first-out characteristics of the above data structures. When the kernel deletes past state histories during a simulation, garbage collection is also performed transparently using the corresponding method

FIFO queue
class library
time warp simulation
performance evaluation
easy-to-use interface
queuing simulations
parallel discrete simulations
general-purpose simulation libraries
simulation languages
state vectors
dynamic data structures
embedded data structures
operational history
first-in-first-out characteristics
garbage collection
object oriented method
state management


Infrared-image classification using hidden Markov trees

Abstract: An image of a three-dimensional target is generally characterized by the visible target subcomponents, with these dictated by the target-sensor orientation (target pose). An image often changes quickly with variable pose. We define a class as a set of contiguous target-sensor orientations over which the associated target image is relatively stationary with aspect. Each target is in general characterized by multiple classes. A distinct set of Wiener filters are employed for each class of images, to identify the presence of target subcomponents. A Karhunen-Loeve representation is used to minimize the number of filters (templates) associated with a given subcomponent. The statistical relationships between the different target subcomponents are modeled via a hidden Markov tree (HMT). The HMT classifier is discussed and example results are presented for forward-looking-infrared (FLIR) imagery of several vehicles

IR image classification
infrared-image classification
hidden Markov trees
3D target image
target-sensor orientation
target pose
contiguous target-sensor orientations
Wiener filters
Karhunen-Loeve representation
minimization
HMT
forward-looking-infrared imagery
FLIR imagery
vehicles


Will CPXe save the photofinishing market?

Abstract: A consortium of film suppliers and electronics firms has proposed the Common Picture Exchange environment. It will let diverse providers cooperate via the Internet to sell digital-photo prints

CPXe
photofinishing market
Common Picture Exchange environment
Kodak
Fujifilm
HP
Web-services standards


Hardware and software platform for real-time processing and visualization of echographic radiofrequency signals

Abstract: In this paper the architecture of a hardware and software platform, for ultrasonic investigation is presented. The platform, used in conjunction with an analog front-end hardware for driving the ultrasonic transducers of any commercial echograph, having the radiofrequency echo signal access, make it possible to dispose of a powerful echographic system for experimenting any processing technique, also in a clinical environment in which real-time operation mode is an essential prerequisite. The platform transforms any echograph into a test-system for evaluating the diagnostic effectiveness of new investigation techniques. A particular user interface was designed in order to allow a real-time and simultaneous visualization of the results produced in the different stages of the chosen processing procedure. This is aimed at obtaining a better optimization of the processing algorithm. The most important platform aspect, which also constitutes the basic differentiation with respect to similar systems, is the direct processing of the radiofrequency echo signal, which is essential for a complete analysis of the particular ultrasound-media interaction phenomenon. The platform completely integrates the architecture of a personal computer (PC) giving rise to several benefits, such as the quick technological evolution in the PC field and an extreme degree of programmability for different applications. The PC also constitutes the user interface, as a flexible and intuitive visualization support, and performs some software signal processing, by custom algorithms and commercial libraries. The realized close synergy between hardware and software allows the acquisition and real-time processing of the echographic radiofrequency (RF) signal with fast data representation

echographic radiofrequency signal
real-time processing
data visualization
hardware platform
software platform
ultrasonic imaging
clinical diagnosis
user interface
personal computer


Optimal allocation of runs in a simulation metamodel with several independent variables

Abstract: Cheng and Kleijnen (1999) propose a very general regression metamodel for modelling the output of a queuing system. Its main limitations are that the regression function is based on a polynomial and that it can use only one independent variable. These limitations are removed here. We derive an explicit formula for the optimal way of assigning simulation runs to the different design points

optimal runs allocation
simulation metamodel
independent variables
general regression metamodel
queuing system
regression function


Analogue realizations of fractional-order controllers

Abstract: An approach to the design of analogue circuits, implementing fractional-order controllers, is presented. The suggested approach is based on the use of continued fraction expansions; in the case of negative coefficients in a continued fraction expansion, the use of negative impedance converters is proposed. Several possible methods for obtaining suitable rational approximations and continued fraction expansions are discussed. An example of realization of a fractional-order I/sup lambda / controller is presented and illustrated by obtained measurements. The suggested approach can be used for the control of very fast processes, where the use of digital controllers is difficult or impossible

analogue realizations
fractional-order controllers
continued fraction expansions
negative coefficients
fraction expansion
negative impedance converters
rational approximations
fast processes
digital controllers
fractional differentiation
fractional integration


A conflict between language and atomistic information

Abstract: Fred Dretske and Jerry Fodor are responsible for popularizing three well-known theses in contemporary philosophy of mind: the thesis of Information-Based Semantics (IBS), the thesis of Content Atomism (Atomism) and the thesis of the Language of Thought (LOT). LOT concerns the semantically relevant structure of representations involved in cognitive states such as beliefs and desires. It maintains that all such representations must have syntactic structures mirroring the structure of their contents. IBS is a thesis about the nature of the relations that connect cognitive representations and their parts to their contents (semantic relations). It holds that these relations supervene solely on relations of the kind that support information content, perhaps with some help from logical principles of combination. Atomism is a thesis about the nature of the content of simple symbols. It holds that each substantive simple symbol possesses its content independently of all other symbols in the representational system. I argue that Dretske's and Fodor's theories are false and that their falsehood results from a conflict IBS and Atomism, on the one hand, and LOT, on the other

philosophy of mind
Information-Based Semantics
Content Atomism
IBS
Language of Thought
LOT
cognitive states
beliefs
desires


On conflict-free executions of elementary nets

Abstract: Deals with analysis of elementary Petri nets with respect to possibilities of avoiding conflicts during their executions. There are two main aims of the paper. The first is to find a method of checking if a net is conflict-avoidable (i.e., if it possesses a conflict-free fair run). The second is to find a method of rebuilding any net to a totally conflict-avoidable net (i.e., a net possessing a conflict-free fair run in every one process) with the same behaviour. The main results are the following: 1. The proof of decidability, for elementary nets, of the problem of existence of a conflict-avoidable fair process (and an algorithm producing all fair runs). 2. Construction, for an arbitrary given elementary net, of a totally conflict-avoidable net with the same behaviour. The net, completed this way, has the same behaviour as the original one. Moreover, it is totally conflict-avoidable, and its execution may be supervised (in order to ensure conflict-freeness) by the reduced case graph built by the algorithm of the former section

conflict-free executions
elementary Petri nets
conflict-free fair run
totally conflict-avoidable net
decidability
reduced case graph


Stability analysis of the characteristic polynomials whose coefficients are polynomials of interval parameters using monotonicity

Abstract: We analyze the stability of the characteristic polynomials whose coefficients are polynomials of interval parameters via monotonicity methods. Our stability conditions are based on Frazer-Duncan's theorem and all conditions can be checked using only endpoint values of interval parameters. These stability conditions are necessary and sufficient under the monotonicity assumptions. When the monotonicity conditions do not hold on the whole parameter region, we present an interval division method and a transformation algorithm in order to apply the monotonicity conditions. Then, our stability analysis methods can be applied to all characteristic polynomials whose coefficients are polynomials of interval parameters

stability analysis
characteristic polynomials
interval parameters
monotonicity
Frazer-Duncan theorem
endpoint values
necessary and sufficient conditions
interval division method
transformation algorithm


New thinking on rendering

Abstract: Looks at how graphics hardware solves a range of rendering problems

rendering
graphics hardware
programmability
Gourand-shaded image
color values


Calibrated initials for an EM applied to recursive models of categorical variables

Abstract: The estimates from an EM, when it is applied to a large causal model of 10 or more categorical variables, are often subject to the initial values for the estimates. This phenomenon becomes more serious as the model structure becomes more complicated involving more variables. As a measure of compensation for this, it has been recommended in literature that EMs are implemented several times with different sets of initial values to obtain more appropriate estimates. We propose an improved approach for initial values. The main idea is that we use initials that are calibrated to data. A simulation result strongly indicates that the calibrated initials give rise to the estimates that are far closer to the true values than the initials that are not calibrated

EM
recursive models
categorical variables
calibrated initials
large causal model
initial values
simulation


Three-dimensional global MHD simulation code for the Earth's magnetosphere using HPF/JA

Abstract: We have translated a three-dimensional magnetohydrodynamic (MHD) simulation code of the Earth's magnetosphere from VPP Fortran to HPF/JA on the Fujitsu VPP5000/56 vector-parallel supercomputer and the MHD code was fully vectorized and fully parallelized in VPP Fortran. The entire performance and capability of the HPF MHD code could be shown to be almost comparable to that of VPP Fortran. A three-dimensional global MHD simulation of the Earth's magnetosphere was performed at a speed of over 400 Gflops with an efficiency of 76.5% using 56 processing elements of the Fujitsu VPP5000/56 in vector and parallel computation that permitted comparison with catalog values. We have concluded that fluid and MHD codes that are fully vectorized and fully parallelized in VPP Fortran can be translated with relative ease to HPF/JA, and a code in HPF/JA may be expected to perform comparably to the same code written in VPP Fortran

magnetohydrodynamic simulation
vector-parallel supercomputer
Fujitsu VPP5000/56
HPF MHD code
MHD simulation
parallel computation


Decomposition of additive cellular automata

Abstract: Finite additive cellular automata with fixed and periodic boundary conditions are considered as endomorphisms over pattern spaces. A characterization of the nilpotent and regular parts of these endomorphisms is given in terms of their minimal polynomials. Generalized eigenspace decomposition is determined and relevant cyclic subspaces are described in terms of symmetries. As an application, the lengths and frequencies of limit cycles in the transition diagram of the automaton are calculated

cellular automata
finite cellular automaton
transition diagram
endomorphisms
computational complexity


The fully entangled fraction as an inclusive measure of entanglement applications

Abstract: Characterizing entanglement in all but the simplest case of a two qubit pure state is a hard problem, even understanding the relevant experimental quantities that are related to entanglement is difficult. It may not be necessary, however, to quantify the entanglement of a state in order to quantify the quantum information processing significance of a state. It is known that the fully entangled fraction has a direct relationship to the fidelity of teleportation maximized under the actions of local unitary operations. In the case of two qubits we point out that the fully entangled fraction can also be related to the fidelities, maximized under the actions of local unitary operations, of other important quantum information tasks such as dense coding, entanglement swapping and quantum cryptography in such a way as to provide an inclusive measure of these entanglement applications. For two qubit systems the fully entangled fraction has a simple known closed-form expression and we establish lower and upper bounds of this quantity with the concurrence. This approach is readily extendable to more complicated systems

entanglement
two qubit pure state
quantum information processing
fully entangled fraction
fidelity
teleportation
entanglement swapping
quantum cryptography


A high-resolution high-frequency monolithic top-shooting microinjector free of satellite drops - part I: concept, design, and model

Abstract: Introduces an innovative microinjector design, featuring a bubble valve, which entails superior droplet ejection characteristics and monolithic fabrication, which allows handling of a wide range of liquids. This new microinjector uses asymmetric bubbles to reduce crosstalk, increase frequency response and eliminate satellite droplets. During a firing, i.e., droplet ejection, the "virtual valve" closes, by growing a thermal bubble in the microchannel, to isolate the microchamber from the liquid supply and neighboring chambers. Between firings, however, the virtual valve opens, by collapsing the bubble, to reduce flow restriction for fast refilling of the microchamber. The use of bubble valves brings about fast and reliable device operation without imposing the significant complication fabrication of physical microvalves would call for. In addition, through a special heater configuration and chamber designs, bubbles surrounding the nozzle cut off the tail of the droplets being ejected and completely eliminate satellite droplets. A simple one-dimensional model of the operation of the microinjector is used to estimate the bubble formation and liquid refilling

monolithic top-shooting microinjector
bubble valve
droplet ejection characteristics
asymmetric bubbles
crosstalk
liquid refilling
frequency response
satellite droplets
virtual valve
inkjet printing
thermal bubble jet
flow restriction
chamber designs


TCP explicit congestion notification over ATM-UBR: a simulation study

Abstract: The enhancement of transmission control protocol's (TCP's) congestion control mechanisms using explicit congestion notification (ECN) over asynchronous transfer mode (ATM) networks is overviewed. TCP's congestion control is enhanced so that congestion is indicated by not only packet losses as is currently the case but an agent implemented at the ATM network's edge as well. The novel idea uses EFCI (explicit forward congestion indication) bits (available in every ATM cell header) to generalize the ECN response to the UBR (unspecified bit rate) service, notify congestion, and adjust the credit-based window size of the TCR. The authors' simulation experiments show that TCP ECN achieves significantly lower cell loss, packet retransmissions, and buffer utilization, and exhibits better throughput than (non-ECN) TCP Reno

explicit forward congestion indication bits


Universal approximation by hierarchical fuzzy system with constraints on the fuzzy rule

Abstract: This paper presents a special hierarchical fuzzy system where the outputs of the previous layer are not used in the IF-parts, but used only in the THEN-parts of the fuzzy rules of the current layer. The proposed scheme can be shown to be a universal approximator to any continuous function on a compact set if complete fuzzy sets are used in the IF-parts of the fuzzy rules with singleton fuzzifier and center average defuzzifier. From the simulation of ball and beam control system, it is demonstrated that the proposed scheme approximates with good accuracy the model nonlinear controller with fewer fuzzy rules than the centralized fuzzy system and its control performance is comparable to that of the nonlinear controller

hierarchical fuzzy system
fuzzy rules
universal approximator
continuous function
ball and beam control system
hierarchical fuzzy logic
Stone-Weierstrass theorem


Approximating martingales for variance reduction in Markov process simulation

Abstract: "Knowledge of either analytical or numerical approximations should enable more efficient simulation estimators to be constructed." This principle seems intuitively plausible and certainly attractive, yet no completely satisfactory general methodology has been developed to exploit it. The authors present a new approach for obtaining variance reduction in Markov process simulation that is applicable to a vast array of different performance measures. The approach relies on the construction of a martingale that is then used as an internal control variate

Markov process simulation
variance reduction
approximating martingale-process method
martingales
performance measures
internal control variate
complex stochastic processes
single-server queue


A notion of non-interference for timed automata

Abstract: The non-interference property of concurrent systems is a security property concerning the flow of information among different levels of security of the system. In this paper we introduce a notion of timed non-interference for real-time systems specified by timed automata. The notion is presented using an automata based approach and then it is characterized also by operations and equivalence between timed languages. The definition is applied to an example of a time-critical system modeling a simplified control of an airplane

timed automata
noninterference notion
concurrent systems
security property
real-time systems
time-critical system


Robust output-feedback control for linear continuous uncertain state delayed systems with unknown time delay

Abstract: The state-delayed time often is unknown and independent of other variables in most real physical systems. A new stability criterion for uncertain systems with a state time-varying delay is proposed. Then, a robust observer-based control law based on this criterion is constructed via the sequential quadratic programming method. We also develop a separation property so that the state feedback control law and observer can be independently designed and maintain closed-loop system stability. An example illustrates the availability of the proposed design method

robust control
output-feedback control
linear continuous systems
uncertain systems
state delayed systems
time delay
state time-varying delay
observer-based control law
sequential quadratic programming
state feedback control law
closed-loop system stability


Variety identification of wheat using mass spectrometry with neural networks and the influence of mass spectra processing prior to neural network analysis

Abstract: The performance of matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry with neural networks in wheat variety classification is further evaluated. Two principal issues were studied: (a) the number of varieties that could be classified correctly; and (b) various means of preprocessing mass spectrometric data. The number of wheat varieties tested was increased from 10 to 30. The main pre-processing method investigated was based on Gaussian smoothing of the spectra, but other methods based on normalisation procedures and multiplicative scatter correction of data were also used. With the final method, it was possible to classify 30 wheat varieties with 87% correctly classified mass spectra and a correlation coefficient of 0.90


Watermarking techniques for electronic delivery of remote sensing images

Abstract: Earth observation missions have recently attracted a growing interest, mainly due to the large number of possible applications capable of exploiting remotely sensed data and images. Along with the increase of market potential, the need arises for the protection of the image products. Such a need is a very crucial one, because the Internet and other public/private networks have become preferred means of data exchange. A critical issue arising when dealing with digital image distribution is copyright protection. Such a problem has been largely addressed by resorting to watermarking technology. A question that obviously arises is whether the requirements imposed by remote sensing imagery are compatible with existing watermarking techniques. On the basis of these motivations, the contribution of this work is twofold: assessment of the requirements imposed by remote sensing applications on watermark-based copyright protection, and modification of two well-established digital watermarking techniques to meet such constraints. More specifically, the concept of near-lossless watermarking is introduced and two possible algorithms matching such a requirement are presented. Experimental results are shown to measure the impact of watermark introduction on a typical remote sensing application, i.e., unsupervised image classification

remote sensing images
electronic delivery
watermarking techniques
Earth observation missions
copyright protection
digital watermarking
near-lossless watermarking
digital image distribution
unsupervised image classification


Adaptive scheduling of batch servers in flow shops

Abstract: Batch servicing is a common way of benefiting from economies of scale in manufacturing operations. Good examples of production systems that allow for batch processing are ovens found in the aircraft industry and in semiconductor manufacturing. In this paper we study the issue of dynamic scheduling of such systems within the context of multi-stage flow shops. So far, a great deal of research has concentrated on the development of control strategies, which only address the batch stage. This paper proposes an integral scheduling approach that also includes succeeding stages. In this way, we aim for shop optimization, instead of optimizing performance for a single stage. Our so-called look-ahead strategy adapts its scheduling decision to shop status, which includes information on a limited number of near-future arrivals. In particular, we study a two-stage flow shop, in which the batch stage is succeeded by a serial stage. The serial stage may be realized by a single machine or by parallel machines. Through an extensive simulation study it is demonstrated how shop performance can be improved by the proposed strategy relative to existing strategies

adaptive scheduling
batch servers
flow shops
batch servicing
manufacturing operations
production systems
ovens
aircraft industry
semiconductor manufacturing
dynamic scheduling
multi-stage flow shops
control strategies
integral scheduling approach
shop optimization
look-ahead strategy
near-future arrivals
two-stage flow shop
single machine
parallel machines
simulation study


A look at MonacoProfiler 4

Abstract: The newest profiling program from Monaco Software adds some valuable features: support for up to 8-color printing, profiling for digital cameras, fine-tuning of black generation and tweaking of profile transforms. We tested its ease of use and a few of the advanced functions. In all, it's pretty good

MonacoProfiler 4
color-correction
Pantone Hexachrome
commercial printers


Pareto-optimal formulations for cost versus colorimetric accuracy trade-offs in printer color management

Abstract: Color management for the printing of digital images is a challenging task, due primarily to nonlinear ink-mixing behavior and the presence of redundant solutions for print devices with more than three inks. Algorithms for the conversion of image data to printer-specific format are typically designed to achieve a single predetermined rendering intent, such as colorimetric accuracy. We present two CIELAB to CMYK color conversion schemes based on a general Pareto-optimal formulation for printer color management. The schemes operate using a 149-color characterization data set selected to efficiently capture the entire CMYK gamut. The first scheme uses artificial neural networks as transfer functions between the CIELAB and CMYK spaces. The second scheme is based on a reformulation of tetrahedral interpolation as an optimization problem. Characterization data are divided into tetrahedra for the interpolation-based approach using the program Qhull, which removes the common restriction that characterization data be well organized. Both schemes offer user control over trade-off problems such as cost versus reproduction accuracy, allowing for user-specified print objectives and the use of constraints such as maximum allowable ink and maximum allowable AE*/sub ab/. A formulation for minimization of ink is shown to be particularly favorable, integrating both a clipping and gamut compression features into a single methodology

P R P P P P R P R P P P P P P R P P P P P P P U U P


Web services boost integration

Abstract: Microsoft and IBM have announced products to help their database software co-exist with competitors' offerings. The products use web services technology allowing users to improve integration between databases and application software from rival vendors

web services technology
Microsoft
IBM
database software


North American carrier survey: simply the best

Abstract: Network Magazine carried out a North American carrier survey. Thousands of network engineers gave information on providers' strengths and weaknesses across seven services: private lines, frame relay, ATM, VPNs, dedicated Internet access, Ethernet services, and Web hosting. Respondents also ranked providers on their ability to perform in up to eight categories including customer service, reliability, and price. Users rated more than a dozen providers for each survey. Carriers needed to receive at least 30 votes for inclusion in the survey. Readers were asked to rate carriers on up to nine categories using a scale of 1 (unacceptable) to 5 (excellent). Not all categories are equally important. To try and get at these differences, Network Magazine asked readers to assign a weight to each category. The big winners were VPNs

North American carrier survey
private lines
frame relay
ATM
VPNs
dedicated Internet access
Ethernet services
Web hosting
service providers
customer service
reliability
price


Routing security in wireless ad hoc networks

Abstract: A mobile ad hoc network consists of a collection of wireless mobile nodes that are capable of communicating with each other without the use of a network infrastructure or any centralized administration. MANET is an emerging research area with practical applications. However, wireless MANET is particularly vulnerable due to its fundamental characteristics, such as open medium, dynamic topology, distributed cooperation, and constrained capability. Routing plays an important role in the security of the entire network. In general, routing security in wireless MANETs appears to be a problem that is not trivial to solve. In this article we study the routing security issues of MANETs, and analyze in detail one type of attack-the "black hole" problem-that can easily be employed against the MANETs. We also propose a solution for the black hole problem for ad hoc on-demand distance vector routing protocol


Cooperative mutation based evolutionary programming for continuous function optimization

Abstract: An evolutionary programming (EP) algorithm adapting a new mutation operator is presented. Unlike most previous EPs, in which each individual is mutated on its own, each individual in the proposed algorithm is mutated in cooperation with the other individuals. This not only enhances convergence speed but also gives more chance to escape from local minima

cooperative mutation based evolutionary programming


Reinventing broadband

Abstract: Many believe that broadband providers need to change their whole approach. The future, then, is in reinventing broadband. That means tiered pricing to make broadband more competitive with dial-up access and livelier, more distinct content: video on demand, MP3, and other features exclusive to the fat-pipe superhighway

MP3
business plans
video on demand
tiered pricing
broadband


Tracking control of the flexible slider-crank mechanism system under impact

Abstract: The variable structure control (VSC) and the stabilizer design by using the pole placement technique are applied to the tracking control of the flexible slider-crank mechanism under impact. The VSC strategy is employed to track the crank angular position and speed, while the stabilizer design is involved to suppress the flexible vibrations simultaneously. From the theoretical impact consideration, three approaches including the generalized momentum balance (GMB), the continuous force model (CFM), and the CFM associated with the effective mass compensation EMC are adopted, and are derived on the basis of the energy and impulse-momentum conservations. Simulation results are provided to demonstrate the performance of the motor-controller flexible slider-crank mechanism not only accomplishing good tracking trajectory of the crank angle, but also eliminating vibrations of the flexible connecting rod

tracking control
flexible slider-crank mechanism system
impact
variable structure control
stabilizer design
crank angular position
flexible vibrations
generalized momentum balance
continuous force model
effective mass compensation
conservation laws
tracking trajectory
flexible connecting rod
multibody dynamics
pole placement technique


A simple etalon-stabilized visible laser diode

Abstract: Visible laser diodes (LDs) are inexpensively available with single-transverse-mode, single-longitudinal-mode operation with a coherence length in the metre range. With constant current bias and constant operating temperature, the optical output power and operating wavelength are stable. A simple and inexpensive way is developed to maintain a constant LD temperature as the temperature of the local environment varies, by monitoring the initially changing wavelength with an external etalon and using this information to apply a heating correction to the monitor photodiode commonly integral to the LD package. The fractional wavelength stability achieved is limited by the solid etalon to 7*10/sup -6/ degrees C/sup -1/

etalon-stabilized laser diode
visible laser diode
constant current bias
constant operating temperature
heating correction
monitor photodiode
fractional wavelength stability
single-transverse-mode
single-longitudinal-mode
index-guided multi-quantum-well
closed-loop operation
feedback loop


Fabrication of polymeric microlens of hemispherical shape using micromolding

Abstract: Polymeric microlenses play an important role in reducing the size, weight, and cost of optical data storage and optical communication systems. We fabricate polymeric microlenses using the microcompression molding process. The design and fabrication procedures for mold insertion is simplified using silicon instead of metal. PMMA powder is used as the molding material. Governed by process parameters such as temperature and pressure histories, the micromolding process is controlled to minimize various defects that develop during the molding process. The radius of curvature and magnification ratio of fabricated microlens are measured as 150 mu m and over 3.0, respectively

polymeric microlens fabrication
micromolding
hemispherical shape microlens
size
weight
cost
optical data storage
optical communication systems
polymeric microlenses
microcompression molding process
fabrication procedures
design procedures
mold insertion
silicon
PMMA powder
molding material
process parameters
temperature
pressure
micromolding process
magnification ratio
300 micron

R P R P P P P P P P P R P P P P P P P P P U


Proof that the election problem belongs to NF-completeness problems in asynchronous distributed systems

Abstract: This paper is about the hardness of the election problem in asynchronous distributed systems in which processes can crash but links are reliable. The hardness of the problem is defined with respect to the difficulty to solve it despite failures. It is shown that problems encountered in the system are classified as three classes of problems: F (fault-tolerant), NF (Not fault-tolerant) and NFC (NF-completeness). Among those, the class NFC are the hardest problems to solve. In this paper, we prove that the Election problem is the most difficult problem which belongs to the class NFC

election problem
NF-completeness problems
asynchronous distributed systems
distributed computing
leader election
failure detectors
fault-tolerant problems
not-fault-tolerant problems


Market watch - air conditioning

Abstract: After a boom period in the late nineties, the air conditioning market finds itself in something of a lull at present, but manufacturers aren't panicking


Fuzzy business [Halden Reactor Project]

Abstract: The Halden Reactor Project has developed two systems to investigate how signal validation and thermal performance monitoring techniques can be improved. PEANO is an online calibration monitoring system that makes use of artificial intelligence techniques. The system has been tested in cooperation with EPRI and Edan Engineering, using real data from a US PWR plant. These tests showed that PEANO could reliably assess the performance of the process instrumentation at different plant conditions. Real cases of zero and span drifts were successfully detected by the system. TEMPO is a system for thermal performance monitoring and optimisation, which relies on plant-wide first principle models. The system has been installed on a Swedish BWR plant. Results obtained show an overall rms deviation from measured values of a few tenths of a percent, and giving goodness-of-fits in the order of 95%. The high accuracy demonstrated is a good basis for detecting possible faults and efficiency losses in steam turbine cycles

Halden Reactor Project
PEANO
calibration
artificial intelligence
fuzzy logic
steam generators
feedwater flow
PWR
TEMPO
thermal performance monitoring
BWR
steam turbine cycles


Computer aided classification of masses in ultrasonic mammography

Abstract: Frequency compounding was recently investigated for computer aided classification of masses in ultrasonic B-mode images as benign or malignant. The classification was performed using the normalized parameters of the Nakagami distribution at a single region of interest at the site of the mass. A combination of normalized Nakagami parameters from two different images of a mass was undertaken to improve the performance of classification. Receiver operating characteristic (ROC) analysis showed that such an approach resulted in an area of 0.83 under the ROC curve. The aim of the work described in this paper is to see whether a feature describing the characteristic of the boundary can be extracted and combined with the Nakagami parameter to further improve the performance of classification. The combination of the features has been performed using a weighted summation. Results indicate a 10% improvement in specificity at a sensitivity of 96% after combining the information at the site and at the boundary. Moreover, the technique requires minimal clinical intervention and has a performance that reaches that of the trained radiologist. It is hence suggested that this technique may be utilized in practice to characterize breast masses

ultrasonic mammography
breast masses
computer aided classification
frequency compounding
ultrasonic B-mode images
benign
malignant
normalized parameters
Nakagami distribution
single region of interest
normalized Nakagami parameters
receiver operating characteristic
ROC curve
weighted summation
specificity
sensitivity
minimal clinical intervention


OMS battle heating up as Chicago Equity ousts LongView for Macgregor

Abstract: Chicago Equity Partners LLC has gone into full production with Macgregor's Financial Trading Platform. This marks a concentrated effort to achieve straight-through processing

Chicago Equity Partners
Macgregor
Financial Trading Platform
straight-through processing
LongView


An on-line distributed intelligent fault section estimation system for large-scale power networks

Abstract: In this paper, a novel distributed intelligent system is suggested for on-line fault section estimation (FSE) of large-scale power networks. As the first step, a multi-way graph partitioning method based on weighted minimum degree reordering is proposed for effectively partitioning the original large-scale power network into the desired number of connected sub-networks with quasi-balanced FSE burdens and minimum frontier elements. After partitioning, a distributed intelligent system based on radial basis function neural network (RBF NN) and companion fuzzy system is suggested for FSE. The relevant theoretical analysis and procedure are presented in the paper. The proposed distributed intelligent FSE method has been implemented with sparse storage technique and tested on the IEEE 14, 30 and 118-bus systems, respectively. Computer simulation results show that the proposed FSE method works successfully for large-scale power networks


Application-layer multicasting with Delaunay triangulation overlays

Abstract: Application-layer multicast supports group applications without the need for a network-layer multicast protocol. Here, applications arrange themselves in a logical overlay network and transfer data within the overlay. We present an application-layer multicast solution that uses a Delaunay triangulation as an overlay network topology. An advantage of using a Delaunay triangulation is that it allows each application to locally derive next-hop routing information without requiring a routing protocol in the overlay. A disadvantage of using a Delaunay triangulation is that the mapping of the overlay to the network topology at the network and data link layer may be suboptimal. We present a protocol, called Delaunay triangulation (DT protocol), which constructs Delaunay triangulation overlay networks. We present measurement experiments of the DT protocol for overlay networks with up to 10 000 members, that are running on a local PC cluster with 100 Linux PCs. The results show that the protocol stabilizes quickly, e.g., an overlay network with 10 000 nodes can be built in just over 30 s. The traffic measurements indicate that the average overhead of a node is only a few kilobits per second if the overlay network is in a steady state. Results of throughput experiments of multicast transmissions (using TCP unicast connections between neighbors in the overlay network) show an achievable throughput of approximately 15 Mb/s in an overlay with 100 nodes and 2 Mb/s in an overlay with 1000 nodes

application-layer multicasting
Delaunay triangulation overlays
group applications
network-layer multicast protocol
logical overlay network
data transfer
Delaunay triangulation protocol
measurement experiments
overlay networks
local PC cluster
Linux PC
overlay network topology
next-hop routing information
data link layer
DT protocol
network nodes
traffic measurements
average overhead
throughput experiments
multicast transmissions
TCP unicast connections
15 Mbit/s
2 Mbit/s

P P P P P R R P P P P P P P P R P P P P P M M


Design and prototype of a performance tool interface for OpenMP

Abstract: This paper proposes a performance tools interface for OpenMP, similar in spirit to the MPI profiling interface in its intent to define a clear and portable API that makes OpenMP execution events visible to runtime performance tools. We present our design using a source-level instrumentation approach based on OpenMP directive rewriting. Rules to instrument each directive and their combination are applied to generate calls to the interface consistent with directive semantics and to pass context information (e.g., source code locations) in a portable and efficient way. Our proposed OpenMP performance API further allows user functions and arbitrary code regions to be marked and performance measurement to be controlled using new OpenMP directives. To prototype the proposed OpenMP performance interface, we have developed compatible performance libraries for the EXPERT automatic event trace analyzer [17, 18] and the TAU performance analysis framework [13]. The directive instrumentation transformations we define are implemented in a source-to-source translation tool called OPARI. Application examples are presented for both EXPERT and TAU to show the OpenMP performance interface and OPARI instrumentation tool in operation. When used together with the MPI profiling interface (as the examples also demonstrate), our proposed approach provides a portable and robust solution to performance analysis of OpenMP and mixed-mode (OpenMP + MPI) applications

performance tool interface
MPI profiling interface
API
source-level instrumentation approach
OpenMP directive rewriting
directive semantics
arbitrary code regions
performance libraries
EXPERT automatic event trace analyzer
TAU performance analysis framework
source-to-source translation tool
OPARI
parallel programming


Code generator for the HPF Library and Fortran 95 transformational functions

Abstract: One of the language features of the core language of HPF 2.0 (High Performance Fortran) is the HPF Library. The HPF Library consists of 55 generic functions. The implementation of this library presents the challenge that all data types, data kinds, array ranks and input distributions need to be supported. For instance, more than 2 billion separate functions are required to support COPY-SCATTER fully. The efficient support of these billions of specific functions is one of the outstanding problems of HPF. We have solved this problem by developing a library generator which utilizes the mechanism of parameterized templates. This mechanism allows the procedures to be instantiated at compile time for arguments with a specific type, kind, rank and distribution over a specific processor array. We describe the algorithms used in the different library functions. The implementation gives the ease of generating a large number of library routines from a single template. The templates can be extended with special code for specific combinations of the input arguments. We describe in detail the implementation and performance of the matrix multiplication template for the Fujitsu VPP5000 platform

HPF
High Performance Fortran
HPF Library
generic functions
data types
library generator
library functions
parallel computing
parallel languages
code generation
parameterized templates
matrix multiplication


Equilibrium swelling and kinetics of pH-responsive hydrogels: models, experiments, and simulations

Abstract: The widespread application of ionic hydrogels in a number of applications like control of microfluidic flow, development of muscle-like actuators, filtration/separation and drug delivery makes it important to properly understand these materials. Understanding hydrogel properties is also important from the standpoint of their similarity to many biological tissues. Typically, gel size is sensitive to outer solution pH and salt concentration. In this paper, we develop models to predict the swelling/deswelling of hydrogels in buffered pH solutions. An equilibrium model has been developed to predict the degree of swelling of the hydrogel at a given pH and salt concentration in the solution. A kinetic model has been developed to predict the rate of swelling of the hydrogel when the solution pH is changed. Experiments are performed to characterize the mechanical properties of the hydrogel in different pH solutions. The degree of swelling as well as the rate of swelling of the hydrogel are also studied through experiments. The simulations are compared with experimental results and the models are found to predict the swelling/deswelling processes accurately

pH-responsive hydrogels
ionic hydrogels
microfluidic flow
muscle-like actuators
filtration/separation
drug delivery
gel size
swelling/deswelling
buffered pH solutions
equilibrium model
mechanical properties


Deadlock-free scheduling in flexible manufacturing systems using Petri nets

Abstract: This paper addresses the deadlock-free scheduling problem in Flexible Manufacturing Systems. An efficient deadlock-free scheduling algorithm was developed, using timed Petri nets, for a class of FMSs called Systems of Sequential Systems with Shared Resources (S/sup 4/ R). The algorithm generates a partial reachability graph to find the optimal or near-optimal deadlock-free schedule in terms of the firing sequence of the transitions of the Petri net model. The objective is to minimize the mean flow time (MFT). An efficient truncation technique, based on the siphon concept, has been developed and used to generate the minimum necessary portion of the reachability graph to be searched. It has been shown experimentally that the developed siphon truncation technique enhances the ability to develop deadlock-free schedules of systems with a high number of deadlocks, which cannot be achieved using standard Petri net scheduling approaches. It may be necessary, in some cases, to relax the optimality condition for large FMSs in order to make the search effort reasonable. Hence, a User Control Factor (UCF) was defined and used in the scheduling algorithm. The objective of using the UCF is to achieve an acceptable trade-off between the solution quality and the search effort. Its effect on the MFT and the CPU time has been investigated. Randomly generated examples are used for illustration and comparison. Although the effect of UCF did not affect the mean flow time, it was shown that increasing it reduces the search effort (CPU time) significantly

systems of sequential systems with shared resources

Petri net model transitions firing sequence


Securing the Internet routing infrastructure

Abstract: The unprecedented growth of the Internet over the last years, and the expectation of an even faster increase in the numbers of users and networked systems, resulted in the Internet assuming its position as a mass communication medium. At the same time, the emergence of an increasingly large number of application areas and the evolution of the networking technology suggest that in the near future the Internet may become the single integrated communication infrastructure. However, as the dependence on the networking infrastructure grows, its security becomes a major concern, in light of the increased attempt to compromise the infrastructure. In particular, the routing operation is a highly visible target that must be shielded against a wide range of attacks. The injection of false routing information can easily degrade network performance, or even cause denial of service for a large number of hosts and networks over a long period of time. Different approaches have been proposed to secure the routing protocols, with a variety of countermeasures, which, nonetheless, have not eradicated the vulnerability of the routing infrastructure. In this article, we survey the up-to-date secure routing schemes. that appeared over the last few years. Our critical point of view and thorough review of the literature are an attempt to identify directions for future research on an indeed difficult and still largely open problem

Internet routing infrastructure security


Disability-related special libraries

Abstract: One of the ways that the federal government works to improve services to people with disabilities is to fund disability-related information centers and clearinghouses that provide information resources and referrals to disabled individuals, their family members, service providers, and the general public. The Teaching Research Division of Western Oregon University operates two federally funded information centers for people with disabilities: OBIRN (the Oregon Brain Injury Resource Network) and DB-LINK (the National Information Clearinghouse on Children who are Deaf-Blind). Both have developed in-depth library collections and services in addition to typical clearinghouse services. The authors describe how OBIRN and DB-LINK were designed and developed, and how they are currently structured and maintained. Both information centers use many of the same strategies and tools in day-to-day operations, but differ in a number of ways, including materials and clientele


Multi-hour design of survivable classical IP networks

Abstract: Most of Internet intra-domain routing protocols (OSPF, RIP, and IS-IS) are based on shortest path routing. The path length is defined as the sum of metrics associated with the path links. These metrics are often managed by the network administrator. In this context, the design of an Internet backbone network consists in dimensioning the network (routers and transmission links) and establishing the metric. Many requirements have to be satisfied. First, Internet traffic is not static as significant variations can be observed during the day. Second, many failures can occur (cable cuts, hardware failures, software failures, etc.). We present algorithms (meta-heuristics and greedy heuristic) to design Internet backbone networks, taking into account the multi-hour behaviour of traffic and some survivability requirements. Many multi-hour and protection strategies are studied and numerically compared. Our algorithms can be extended to integrate other quality of service constraints

multi-hour design
survivable classical IP networks
Internet intra-domain routing protocols
OSPF
RIP
IS-IS
shortest path routing
path length
path links
network administrator
Internet backbone network
network dimensioning
network routers
Internet traffic
transmission links
network failures
meta-heuristics algorithm
greedy heuristic algorithm
survivability requirements
network protection
quality of service constraints
QoS constraints

P P P P P P P P P P P R R P P R R R P R P M


Implementing equals for mixed-type comparison

Abstract: The idea of comparing objects of different types is not entirely off base, in particular for classes from the same class hierarchy. After all, objects from the same class hierarchy (and by class hierarchy we mean all classes derived from a common superclass other than Object) have something in common, namely at least the superclass part. As we demonstrated in a previous paper (2002), providing a correct implementation of a mixed-type comparison is a non-trivial task. In this article, we will show one way of implementing a mixed-type comparison of objects from the same class hierarchy that meets the requirements of the equals contract

Java
equals contract
transitivity requirement
mixed-type comparison
superclass


WebCAD: A computer aided design tool constrained with explicit 'design for manufacturability' rules for computer numerical control milling

Abstract: A key element in the overall efficiency of a manufacturing enterprise is the compatibility between the features that have been created in a newly designed part, and the capabilities of the downstream manufacturing processes. With this in mind, a process-aware computer aided design (CAD) system called WebCAD has been developed. The system restricts the freedom of the designer in such a way that the designed parts can be manufactured on a three-axis computer numerical control milling machine. This paper discusses the vision of WebCAD and explains the rationale for its development in comparison with commercial CAD/CAM (computer aided design/manufacture) systems. The paper then goes on to describe the implementation issues that enforce the manufacturability rules. Finally, certain design tools are described that aid a user during the design process. Some examples are given of the parts designed and manufactured with WebCAD

WebCAD
computer aided design tool
design for manufacturability rules
computer numerical control milling
manufacturing enterprise efficiency
process-aware CAD system
three-axis CNC milling machine
CAD/CAM systems
manufacturability rules
design tools
Internet-based CAD/CAM


Quantum-controlled measurement device for quantum-state discrimination

Abstract: We propose a "programmable" quantum device that is able to perform a specific generalized measurement from a certain set of measurements depending on a quantum state of a "program register." In particular, we study a situation when the programmable measurement device serves for the unambiguous discrimination between nonorthogonal states. The particular pair of states that can be unambiguously discriminated is specified by the state of a program qubit. The probability of successful discrimination is not optimal for all admissible pairs. However, for some subsets it can be very close to the optimal value

quantum-controlled measurement device
quantum-state discrimination
programmable quantum device
quantum state
program register
nonorthogonal states
program qubit


Error-probability analysis of MIL-STD-1773 optical fiber data buses

Abstract: We have analyzed the error probabilities of MIL-STD-1773 optical fiber data buses with three modulation schemes, namely, original Manchester II bi-phase coding, PTMBC, and EMBC-BSF. Using these derived expressions of error probabilities, we can also compare the receiver sensitivities of such optical fiber data buses

error probabilities
optical fiber data buses
modulation schemes
Manchester bi-phase coding
receiver sensitivities


Rise of the supercompany [CRM]

Abstract: All the thoughts, conversations and notes of employees help the firm create a wider picture of business. Customer relationship management (CRM) feeds on data, and it is hungry

customer relationship management
central data repository
database
staff trained


Swamped by data [storage]

Abstract: While the cost of storage has plummeted, the demand continued to climb and there are plenty of players out there offering solutions to a company's burgeoning storage needs

cost of storage
IT personnel
resource management
disk capacity management
disk optimisation
file system automation
storage virtualisation
storage area networks
network attached storage


Achieving competitive capabilities in e-services

Abstract: What implications does the Internet have for service operations strategy? How can business performance of e-service companies be improved in today's knowledge-based economy? These research questions are the subject of the paper. We propose a model that links the e-service company's knowledge-based competencies with their competitive capabilities. Drawing from the current literature, our analysis suggests that services that strategically build a portfolio of knowledge-based competencies, namely human capital, structural capital, and absorptive capacity have more operations-based options, than their counterparts who are less apt to invest. We assume that the combinative capabilities of service quality, delivery, flexibility, and cost are determined by the investment in intellectual capital. Arguably, with the advent of the Internet, different operating models (e.g., bricks-and-mortar, clicks-and-mortar, or pure dot-com) have different strategic imperatives in terms of knowledge-based competencies. Thus, the new e-operations paradigm can be viewed as a configuration of knowledge-based competencies and capabilities

competitive capabilities
e-services
Internet
service operations strategy
business performance
knowledge-based economy
knowledge-based competencies
human capital
structural capital
absorptive capacity
operations-based options
combinative capabilities
service quality
delivery
flexibility
cost
investment
intellectual capital
bricks-and-mortar
clicks-and-mortar
dot-com
strategic imperatives

P P P P P P P P P P P P P P P P P P P P P P


Application of an internally consistent material model to determine the effect of tool edge geometry in orthogonal machining

Abstract: It is well known that the edge geometry of a cutting tool affects the forces measured in metal cutting. Two experimental methods have been suggested in the past to extract the ploughing (non-cutting) component from the total measured force: (1) the extrapolation approach, and (2) the dwell force technique. This study reports the behavior of zinc during orthogonal machining using tools of controlled edge radius. Applications of both the extrapolation and dwell approaches show that neither produces an analysis that yields a material response consistent with the known behavior of zinc. Further analysis shows that the edge geometry modifies the shear zone of the material and thereby modifies the forces. When analyzed this way, the measured force data yield the expected material response without requiring recourse to an additional ploughing component

tool edge geometry
cutting tool
metal cutting
ploughing component
extrapolation
dwell force
zinc
edge geometry
orthogonal machining


Evolution complexity of the elementary cellular automaton rule 18

Abstract: Cellular automata are classes of mathematical systems characterized by discreteness (in space, time, and state values), determinism, and local interaction. Using symbolic dynamical theory, we coarse-grain the temporal evolution orbits of cellular automata. By means of formal languages and automata theory, we study the evolution complexity of the elementary cellular automaton with local rule number 18 and prove that its width 1-evolution language is regular, but for every n >or= 2 its width n-evolution language is not context free but context sensitive

cellular automata
symbolic dynamical theory
formal languages
complexity
evolution complexity
elementary cellular automaton


On fractal dimension in information systems. Toward exact sets in infinite information systems

Abstract: The notions of an exact as well as a rough set are well-grounded as basic notions in rough set theory. They are however defined in the setting of a finite information system i.e. an information system having finite numbers of objects as well as attributes. In theoretical studies e.g. of topological properties of rough sets, one has to trespass this limitation and to consider information systems with potentially unbound number of attributes. In such setting, the notions of rough and exact sets may be defined in terms of topological operators of interior and closure with respect to an appropriate topology following the ideas from the finite case, where it is noticed that in the finite case rough-set-theoretic operators of lower and upper approximation are identical with the interior, respectively, closure operators in topology induced by equivalence classes of the indiscernibility relation. Extensions of finite information systems are also desirable from application point of view in the area of knowledge discovery and data mining, when demands of e.g. mass collaboration and/or huge experimental data call for need of working with large data tables so the sound theoretical generalization of these cases is an information system with the number of attributes not bound in advance by a fixed integer i.e. an information system with countably but infinitely many attributes, In large information systems, a need arises for qualitative measures of complexity of concepts involved free of parameters, cf. e.g. applications for the Vapnik-Czervonenkis dimension. We study here in the theoretical setting of infinite information system a proposal to apply fractal dimensions suitably modified as measures of concept complexity

fractal dimension
information systems
exact sets
infinite information systems
rough set
topological properties
closure operators
equivalence classes
knowledge discovery
data mining
qualitative measures
complexity


Design of high-performance wavelets for image coding using a perceptual time domain criterion

Abstract: This paper presents a new biorthogonal linear-phase wavelet design for image compression. Instead of calculating the prototype filters as spectral factors of a half-band filter, the design is based on the direct optimization of the low pass analysis filter using an objective function directly related to a perceptual criterion for image compression. This function is defined as the product of the theoretical coding gain and an index called the peak-to-peak ratio, which was shown to have high correlation with perceptual quality. A distinctive feature of the proposed technique is a procedure by which, given a "good" starting filter, "good" filters of longer lengths are generated. The results are excellent, showing a clear improvement in perceptual image quality. Also, we devised a criterion for constraining the coefficients of the filters in order to design wavelets with minimum ringing


Verification of timed automata based on similarity

Abstract: The paper presents a modification of the standard partitioning technique to generate abstract state spaces preserving similarity for Timed Automata. Since this relation is weaker than bisimilarity, most of the obtained models (state spaces) are smaller than bisimilar ones, but still preserve the universal fragments of branching time temporal logics. The theoretical results are exemplified for strong, delay, and observational simulation relations

timed automata verification
partitioning technique
abstract state spaces
bisimilarity
universal fragments
branching time temporal logics
observational simulation relations


Measuring return: revealing ROI

Abstract: The most critical part of the return-on-investment odyssey is to develop metrics that matter to the business and to measure systems in terms of their ability to help achieve those business goals. Everything must flow from those key metrics. And don't forget to revisit those every now and then, too. Since all systems wind down over time, it's important to keep tabs on how well your automation investment is meeting the metrics established by your company. Manufacturers are clamoring for a tool to help quantify returns and analyze the results

technology purchases
return-on-investment
ROI
key metrics
automation investment


Separate accounts go mainstream [investment]

Abstract: New entrants are shaking up the separate-account industry by supplying Web-based platforms that give advisers the tools to pick independent money managers

separate-account industry
Web-based platforms
independent money managers
investment
financial advisors


Implementation of universal quantum gates based on nonadiabatic geometric phases

Abstract: We propose an experimentally feasible scheme to achieve quantum computation based on nonadiabatic geometric phase shifts, in which a cyclic geometric phase is used to realize a set of universal quantum gates. Physical implementation of this set of gates is designed for Josephson junctions and for NMR systems. Interestingly, we find that the nonadiabatic phase shift may be independent of the operation time under appropriate controllable conditions. A remarkable feature of the present nonadiabatic geometric gates is that there is no intrinsic limitation on the operation time

quantum computation
nonadiabatic geometric phase shifts
cyclic geometric phase
universal quantum gates
Josephson junctions
NMR systems
nonadiabatic phase shift
operation time
nonadiabatic geometric gates


If the RedBoot fits [open-source ROM monitor]

Abstract: Many embedded developers today use a ROM- or flash-resident software program that provides functionality such as loading and running application software, scripting, read/write access to processor registers, and memory dumps. A ROM monitor, as it is often called, can be a useful and far less expensive debugging tool than an in-circuit emulator. This article describes the RedBoot ROM monitor. It takes a look at the features offered by the RedBoot ROM monitor and sees how it can be configured. It also walks through the steps of rebuilding and installing a new RedBoot image on a target platform. Finally, it looks at future enhancements that are coming in new releases and how to get support and additional information when using RedBoot. Although RedBoot uses software modules from the eCos real-time operating system (RTOS) and is often used in systems running embedded Linux, it is completely independent of both operating systems. RedBoot can be used with any operating system or RTOS, or even without one

RedBoot
open-source ROM monitor
embedded systems
flash-resident software program
scripting
processor register access
memory dumps
debugging tool
bootstrapping
eCos
real-time operating system
embedded Linux


High-performance servo systems based on multirate sampling control

Abstract: In this paper, novel multirate two-degree-of-freedom controllers are proposed for digital control systems, in which the sampling period of plant output is restricted to be relatively longer than the control period of plant input. The proposed feedforward controller assures perfect tracking at M inter-sampling points. On the other hand, the proposed feedback controller assures perfect disturbance rejection at M inter-sample points in the steady state. Illustrative examples of position control for hard disk drive are presented, and advantages of these approaches are demonstrated

multirate sampling control
servo system
digital control systems
tracking
feedback
feedforward
position control
hard disk drive
disturbance rejection


Improved analysis for the nonlinear performance of CMOS current mirrors with device mismatch

Abstract: The nonlinear performance of the simple and complementary MOSFET current mirrors are analyzed. Closed-form expressions are obtained for the harmonic and intermodulation components resulting from a multisinusoidal input current. These expressions can be used for predicting the limiting values of the input current under prespecified conditions of threshold-voltage mismatches and/or transconductance mismatches. The case of a single input sinusoid is discussed in detail and the results are compared with SPICE simulations

nonlinear performance
CMOS current mirrors
device mismatch
complementary MOSFET current mirrors
closed-form expressions
harmonic components
intermodulation components
multisinusoidal input current
input current
threshold-voltage mismatch
SPICE simulations
simulation results
transconductance mismatch


AGC for autonomous power system using combined intelligent techniques

Abstract: In the present work two intelligent load frequency controllers have been developed to regulate the power output and system frequency by controlling the speed of the generator with the help of fuel rack position control. The first controller is obtained using fuzzy logic (FL) only, whereas the second one by using a combination of FL, genetic algorithms and neural networks. The aim of the proposed controller(s) is to restore in a very smooth way the frequency to its nominal value in the shortest time possible whenever there is any change in the load demand etc. The action of these controller(s) provides a satisfactory balance between frequency overshoot and transient oscillations with zero steady-state error. The design and performance evaluation of the proposed controller(s) structure are illustrated with the help of case studies applied (without loss of generality) to a typical single-area power system. It is found that the proposed controllers exhibit satisfactory overall dynamic performance and overcome the possible drawbacks associated with other competing techniques

autonomous power system
combined intelligent techniques
power output regulation
generator speed control
fuel rack position control
fuzzy logic
genetic algorithms
neural networks
load demand
frequency overshoot
transient oscillations
zero steady-state error
performance evaluation
single-area power system
overall dynamic performance
competing techniques
frequency control
controller design


Mapping CCF to MARC21: an experimental approach

Abstract: The purpose of this article is to raise and address a number of issues pertaining to the conversion of Common Communication Format (CCF) into MARC21. In this era of global resource sharing, exchange of bibliographic records from one system to another is imperative in today's library communities. Instead of using a single standard to create machine-readable catalogue records, more than 20 standards have emerged and are being used by different institutions. Because of these variations in standards, sharing of resources and transfer of data from one system to another among the institutions locally and globally has become a significant problem. Addressing this problem requires keeping in mind that countries such as India and others in southeast Asia are using the CCF as a standard for creating bibliographic cataloguing records. This paper describes a way to map the bibliographic catalogue records from CCF to MARC21, although 100% mapping is not possible. In addition, the paper describes an experimental approach that enumerates problems that may occur during the mapping of records/exchanging of records and how these problems can be overcome

Common Communication Format conversion
MARC21
global resource sharing
bibliographic records exchange
library communities
machine-readable catalogue records
standards
data transfer
India
southeast Asia
CCF to MARC21 mapping


From continuous recovery to discrete filtering in numerical approximations of conservation laws

Abstract: Modern numerical approximations of conservation laws rely on numerical dissipation as a means of stabilization. The older, alternative approach is the use of central differencing with a dose of artificial dissipation. In this paper we review the successful class of weighted essentially non-oscillatory finite volume schemes which comprise sophisticated methods of the first kind. New developments in image processing have made new devices possible which can serve as highly nonlinear artificial dissipation terms. We view artificial dissipation as discrete filter operation and introduce several new algorithms inspired by image processing


A brief guide to competitive intelligence: how to gather and use information on competitors

Abstract: The author outlines the processes involved in competitive intelligence, and discusses what it is, how to do it and gives examples of what happens when companies fail to monitor their competitive environment effectively. The author presents a case study, showing how the company that produced the pre-cursor to the Barbie doll failed to look at their business environment and how this led to the firm's failure. The author discusses what competitive intelligence is, and what it is not, and why it is important for businesses, and presents three models used to describe the competitive intelligence process, going through the various steps involved in defining intelligence requirements and collecting, analyzing, communicating and utilizing competitive intelligence

competitive intelligence
competitor information
Barbie doll
business environment
intelligence collection
intelligence analysis
intelligence communication
intelligence utilization


Limitations of delayed state feedback: a numerical study

Abstract: Stabilization of a class of linear time-delay systems can be achieved by a numerical procedure, called the continuous pole placement method [Michiels et al., 2000]. This method can be seen as an extension of the classical pole placement algorithm for ordinary differential equations to a class of delay differential equations. In [Michiels et al., 2000] it was applied to the stabilization of a linear time-invariant system with an input delay using static state feedback. In this paper we study the limitations of such delayed state feedback laws. More precisely we completely characterize the class of stabilizable plants in the 2D-case. For that purpose we make use of numerical continuation techniques. The use of delayed state feedback in various control applications and the effect of its limitations are briefly discussed

linear time-delay systems
continuous pole placement method
delay differential equations
static state feedback
delayed state feedback
numerical continuation


A scalable and lightweight QoS monitoring technique combining passive and active approaches: on the mathematical formulation of CoMPACT monitor

Abstract: To make a scalable and lightweight QoS monitoring system, we (2002) have proposed a new QoS monitoring technique, called the change-of-measure based passive/active monitoring (CoMPACT Monitor), which is based on the change-of-measure framework and is an active measurement transformed by using passively monitored data. This technique enables us to measure detailed QoS information for individual users, applications and organizations, in a scalable and lightweight manner. In this paper, we present the mathematical foundation of CoMPACT Monitor. In addition, we show its characteristics through simulations in terms of typical implementation issues for inferring the delay distributions. The results show that CoMPACT Monitor gives accurate QoS estimations with only a small amount of extra traffic for active measurement

quality of service
change-of-measure
passive monitoring
active monitoring
CoMPACT Monitor
delay distributions
Internet
QoS monitoring
network performance


Evaluation of existing and new feature recognition algorithms. 1. Theory and implementation

Abstract: This is the first of two papers evaluating the performance of general-purpose feature detection techniques for geometric models. In this paper, six different methods are described to identify sets of faces that bound depression and protrusion faces. Each algorithm has been implemented and tested on eight components from the National Design Repository. The algorithms studied include previously published general-purpose feature detection algorithms such as the single-face inner-loop and concavity techniques. Others are improvements to existing algorithms such as extensions of the two-dimensional convex hull method to handle curved faces as well as protrusions. Lastly, new algorithms based on the three-dimensional convex hull, minimum concave, visible and multiple-face inner-loop face sets are described


Simultaneous iterative reconstruction of emission and attenuation images in positron emission tomography from emission data only

Abstract: For quantitative image reconstruction in positron emission tomography attenuation correction is mandatory. In case that no data are available for the calculation of the attenuation correction factors one can try to determine them from the emission data alone. However, it is not clear if the information content is sufficient to yield an adequate attenuation correction together with a satisfactory activity distribution. Therefore, we determined the log likelihood distribution for a thorax phantom depending on the choice of attenuation and activity pixel values to measure the crosstalk between both. In addition an iterative image reconstruction (one-dimensional Newton-type algorithm with a maximum likelihood estimator), which simultaneously reconstructs the images of the activity distribution and the attenuation coefficients is used to demonstrate the problems and possibilities of such a reconstruction. As result we show that for a change of the log likelihood in the range of statistical noise, the associated change in the activity value of a structure is between 6% and 263%. In addition, we show that it is not possible to choose the best maximum on the basis of the log likelihood when a regularization is used, because the coupling between different structures mediated by the (smoothing) regularization prevents an adequate solution due to crosstalk. We conclude that taking into account the attenuation information in the emission data improves the performance of image reconstruction with respect to the bias of the activities, however, the reconstruction still is not quantitative


Wireless-retail financial services: adoption can't justify the cost

Abstract: Slow adoption by retail investors, costly services and bankrupt vendors has prompted banks and brokerage firms to turn off their wireless applications

banks
brokerage firms
wireless applications


Mustering motivation to enact decisions: how decision process characteristics influence goal realization

Abstract: Decision scientists tend to focus mainly on decision antecedents, studying how people make decisions. Action psychologists, in contrast, study post-decision issues, investigating how decisions, once formed, are maintained, protected, and enacted. Through the research presented here, we seek to bridge these two disciplines, proposing that the process by which decisions are reached motivates subsequent pursuit and benefits eventual realization. We identify three characteristics of the decision process (DP) as having motivation-mustering potential: DP effort investment, DP importance, and DP confidence. Through two field studies tracking participants' decision processes, pursuit and realization, we find that after controlling for the influence of the motivational mechanisms of goal intention and implementation intention, the three decision process characteristics significantly influence the successful enactment of the chosen decision directly. The theoretical and practical implications of these findings are considered and future research opportunities are identified

decision enactment
motivation
goal realization
decision process characteristics
action psychologists
post-decision issues
motivation-mustering potential
decision process investment
decision process importance
decision process confidence
goal intention
research opportunities
decision scientists


Analysis of the surface roughness and dimensional accuracy capability of fused deposition modelling processes

Abstract: Building up materials in layers poses significant challenges from the viewpoint of material science, heat transfer and applied mechanics. However, numerous aspects of the use of these technologies have yet to be studied. One of these aspects is the characterization of the surface roughness and dimensional precision obtainable in layered manufacturing processes. In this paper, a study of roughness parameters obtained through the use of these manufacturing processes was made. Prototype parts were manufactured using FDM techniques and an experimental analysis of the resulting roughness average (R/sub a/) and rms roughness (R/sub q/) obtained through the use of these manufacturing processes was carried out. Dimensional parameters were also studied in order to determine the capability of the Fused Deposition Modelling process for manufacturing parts

fused deposition modelling processes
surface roughness
dimensional accuracy capability
dimensional precision
layered manufacturing processes
prototype parts
roughness average
rms roughness
rapid prototyping
three-dimensional solid objects
CAD model
CNC-controlled robot
extrusion head


Simulation study of the cardiovascular functional status in hypertensive situation

Abstract: An extended cardiovascular model was established based on our previous work to study the consequences of physiological or pathological changes to the homeostatic functions of the cardiovascular system. To study hemodynamic changes in hypertensive situations, the impacts of cardiovascular parameter variations (peripheral vascular resistance, arterial vessel wall stiffness and baroreflex gain) upon hemodynamics and the short-term regulation of the cardiovascular system were investigated. For the purpose of analyzing baroregulation function, the short-term regulation of arterial pressure in response to moderate dynamic exercise for normotensive and hypertensive cases was studied through computer simulation and clinical experiments. The simulation results agree well with clinical data. The results of this work suggest that the model presented in this paper provides a useful tool to investigate the functional status of the cardiovascular system in normal or pathological conditions

extended cardiovascular model
pathological changes
physiological changes
homeostatic functions
cardiovascular functional status
hypertensive situation
cardiovascular parameter variations
peripheral vascular resistance
arterial vessel wall stiffness
baroreflex gain
hemodynamics
short-term regulation
arterial pressure
moderate dynamic exercise
normotensive cases
computer simulation
clinical experiments


A round of cash, a pound of flesh [telecom]

Abstract: Despite the upheaval across telecom, venture capital firms are still investing in start-ups. But while a promising idea and a catchy name were enough to guarantee millions in funding at the peak of the dotcom frenzy, now start-ups must prove-their long-term viability, and be willing to concede control of their business to their VC suitors


A scanline-based algorithm for the 2D free-form bin packing problem

Abstract: This paper describes a heuristic algorithm for the 2D free-form bin packing (2D-FBP) problem. Given a set of 2D free-form bins and a set of 2D free-form items, the 2D-FBP problem is to lay out items inside one or more bins in such a way that the number of bins used is minimized, and for each bin, the yield is maximized. The proposed algorithm handles the problem as a variant of the 1D problem; i.e., items and bins are approximated as sets of scanlines, and scanlines are packed. The details of the algorithm are given, and its application to a nesting problem in a shipbuilding company is reported. The proposed algorithm consists of the basic and the group placement algorithms. The basic placement algorithm is a variant of the first-fit decreasing algorithm which is simply extended from the 1D case to the 2D case by a novel scanline approximation. A numerical study with real instances shows that the basic placement algorithm has sufficient performance for most of the instances, however, the group placement algorithm is required when items must be aligned in columns. The qualities of the resulting layouts are good enough for practical use, and the processing times are good

scanline-based algorithm
2D free-form bin packing problem
heuristic algorithm
2D-FBP problem
irregular cutting
irregular packing
nesting problem
minimization
yield maximization
shipbuilding company
group placement algorithm
first-fit decreasing algorithm


The free lunch is over: online content subscriptions on the rise

Abstract: High need, rather than high use, may be what really determines a user's willingness to pay. Retooling and targeting content may be a sharper strategy than trying to re-educate users that it is time to pay up for material that has been free. Waiting for a paradigm shift in general user attitudes about paying for online content Could be a fool's errand

online content subscriptions
content retooling
content targeting
pay-to-play business models


Prediction and compensation of dynamic errors for coordinate measuring machines

Abstract: Coordinate measuring machines (CMMs) are already widely utilized as measuring tools in the modem manufacturing industry. Rapidly approaching now is the trend for next-generation CMMs. However, the increases in measuring velocity of CMM applications are limited by dynamic errors that occur in CMMs. In this paper a systematic approach for modeling the dynamic errors of a touch-trigger probe CMM is developed through theoretical analysis and experimental study. An overall analysis of the dynamic errors of CMMs is conducted, with weak components of the CMM identified by a laser interferometer. The probing process, as conducted with a touch-trigger probe, is analyzed. The dynamic errors are measured, modeled, and predicted using neural networks. The results indicate that, using this mode, it is possible to compensate for the dynamic errors of CMMs

coordinate measuring machines
dynamic errors
inertial forces
touch-trigger probe
laser interferometer
neural networks
manufacturing industry
compensation


Structure of weakly invertible semi-input-memory finite automata with delay 1

Abstract: Semi-input-memory finite automata, a kind of finite automata introduced by the first author of this paper for studying error propagation, are a generalization of input memory finite automata by appending an autonomous finite automaton component. In this paper, we give a characterization of the structure of weakly invertible semi-input-memory finite automata with delay 1, in which the state graph of each autonomous finite automaton is a cycle. From a result on mutual invertibility of finite automata obtained by the authors recently, it leads to a characterization of the structure of feedforward inverse finite automata with delay 1

finite automata
semi-input-memory
invertibility
semi-input-memory finite automata
weakly invertible
delay 1
state graph
feedforward inverse finite automata


Monoids all polygons over which are omega -stable: proof of the Mustafin-Poizat conjecture

Abstract: A monoid S is called an omega -stabilizer (superstabilizer, or stabilizer) if every S-polygon has an omega -stable (superstable, or stable) theory. It is proved that every omega -stabilizer is a regular monoid. This confirms the Mustafin-Poizat conjecture and allows us to end up the description of omega -stabilizers

monoids all polygons
omega -stabilizer
S-polygon
regular monoid
Mustafin-Poizat conjecture


JPEG2000: standard for interactive imaging

Abstract: JPEG2000 is the latest image compression standard to emerge from the Joint Photographic Experts Group (JPEG) working under the auspices of the International Standards Organization. Although the new standard does offer superior compression performance to JPEG, JPEG2000 provides a whole new way of interacting with compressed imagery in a scalable and interoperable fashion. This paper provides a tutorial-style review of the new standard, explaining the technology on which it is based and drawing comparisons with JPEG and other compression standards. The paper also describes new work, exploiting the capabilities of JPEG2000 in client-server systems for efficient interactive browsing of images over the Internet

JPEG2000
interactive imaging
image compression
Joint Photographic Experts Group
International Standards Organization
scalable compression
interoperable compression
review
client-server systems


An approximation to the F distribution using the chi-square distribution

Abstract: For the cumulative distribution function (c.d.f.) of the F distribution, F(x; k, n), with associated degrees of freedom, k and n, a shrinking factor approximation (SFA), G( lambda kx; k), is proposed for large n and any fixed k, where G(x; k) is the chi-square c.d.f. with degrees of freedom, k, and lambda = lambda (kx; n) is the shrinking factor. Numerical analysis indicates that for n/k >or= 3, approximation accuracy of the SFA is to the fourth decimal place for most small values of k. This is a substantial improvement on the accuracy that is achievable using the normal, ordinary chi-square, and Scheffe-Tukey approximations. In addition, it is shown that the theoretical approximation error of the SFA, |F(x; k,n)-G( lambda kx; k)|, is O(1/n/sup 2/) uniformly over x

F distribution
cumulative distribution function
degrees of freedom
shrinking factor approximation
chi-square distribution
numerical analysis


Expert advice - how can my organisation take advantage of reverse auctions without jeopardising existing supplier relationships?

Abstract: In a recent survey, AMR Research found that companies that use reverse auctions to negotiate prices with suppliers typically achieve savings of between 10% and 15% on direct goods and between 20% and 25% on indirect goods, and can slash sourcing cycle times from months to weeks. Suppliers, however, are less enthusiastic. They believe that these savings are achieved only by stripping the human element out of negotiations and evaluating bids on price alone, which drives down their profit margins. As a result, reverse auctions carry the risk of jeopardising long-term and trusted relationships. Suppliers that have not been involved in a reverse auction before typically fear the bidding event itself - arguably the most theatrical and, therefore, most hyped-up part of the process. Although it may only last one hour, weeks of preparation go into setting up a successful bidding event

reverse auctions
supplier relationships
preparation
Request For Quotation


Formalization of weighted factors analysis

Abstract: Weighted factors analysis (WeFA) has been proposed as a new approach for elicitation, representation, and manipulation of knowledge about a given problem, generally at a high and strategic level. Central to this proposal is that a group of experts in the area of the problem can identify a hierarchy of factors with positive or negative influences on the problem outcome. The tangible output of WeFA is a directed weighted graph called a WeFA graph. This is a set of nodes denoting factors that can directly or indirectly influence an overall aim of the graph. The aim is also represented by a node. Each directed arc is a direct influence of one factor on another. A chain of directed arcs indicates an indirect influence. The influences may be identified as either positive or negative. For example, sales and costs are two factors that influence the aim of profitability in an organization. Sales has a positive influence on profitability and costs has a negative influence on profitability. In addition, the relative significance of each influence is represented by a weight. We develop Binary WeFA which is a variant of WeFA where the factors in the graph are restricted to being either true or false. Imposing this restriction on a WeFA graph allows us to be more precise about the meaning of the graph and of reasoning in it. Binary WeFA is a new proposal that provides a formal yet sufficiently simple language for logic-based argumentation for use by business people in decision-support and knowledge management. Whilst Binary WeFA is expressively simpler than other logic-based argumentation formalisms, it does incorporate a novel formalization of the notion of significance

weighted factors analysis
knowledge elicitation
knowledge representation
knowledge manipulation
significance
WeFA graph
directed arc
profitability
organization
Binary WeFA
reasoning
logic-based argumentation
decision-support
knowledge management
directed weighted graph


Topology-adaptive modeling of objects using surface evolutions based on 3D mathematical morphology

Abstract: Level set methods were proposed mainly by mathematicians for constructing a model of a 3D object of arbitrary topology. However, those methods are computationally inefficient due to repeated distance transformations and increased dimensions. In the paper, we propose a new method of modeling fast objects of arbitrary topology by using a surface evolution approach based on mathematical morphology. Given sensor data covering the whole object surface, the method begins with an initial approximation of the object by evolving a closed surface into a model topologically equivalent to the real object. The refined approximation is then performed using energy minimization. The method has been applied in several experiments using range data, and the results are reported in the paper

level set methods
topology-adaptive modeling
surface evolutions
3D mathematical morphology
3D object
arbitrary topology
repeated distance transformations
initial approximation
refined approximation
energy minimization
range data
pseudo curvature flow


A brief history of electronic reserves

Abstract: Electronic reserves has existed as a library service for barely ten years, yet its history, however brief, is important as an indicator of the direction being taken by the profession of Librarianship as a whole. Recent improvements in technology and a desire to provide better service to students and faculty have resulted in the implementation of e-reserves by ever greater numbers of academic libraries. Yet a great deal of confusion still surrounds the issue of copyright compliance. Negotiation, litigation, and legislation in particular have framed the debate over the application of fair use to an e-reserves environment, and the question of whether or not permission fees should be paid to rights holders, but as of yet no definitive answers or standards have emerged

electronic reserves
library service
librarianship
students
faculty
academic libraries
copyright compliance
negotiation
litigation
legislation
e-reserves environment
permission fees