Enlisting on-line residents: Expanding the boundaries of e-government in a Japanese rural township

Abstract: The purpose of this article is to analyze and learn from an unusual way in which local bureaucrats in a Japanese rural township are using the Internet to serve their constituents by enlisting the support of "on-line residents." Successful e-government requires not only rethinking the potential uses of computer technology, but in adopting new patterns of decision-making, power sharing, and office management that many bureaucrats may not be predisposed to make. The main thesis of this article is that necessity and practicality can play a powerful motivational role in facilitating the incorporation of information technology (IT) at the level of local government. This case study of how bureaucrats in Towa-cho, a small, agricultural town in Northeastern Japan, have harnessed the Internet demonstrates clearly the fundamentals of building a successful e-government framework in this rural municipality, similar to many communities in Europe and North America today

on-line residents
e-government
Japanese rural township
local bureaucrats
Internet
decision-making
power sharing
office management
Towa-cho
rural municipality


Community technology and democratic rationalization

Abstract: The objective of the paper is to explore questions of human agency and democratic process in the technical sphere through the example of "virtual community." The formation of relatively stable long-term group associations (community in the broad sense of the term), is the scene on which a large share of human development occurs. As such it is a fundamental human value mobilizing diverse ideologies and sensitivities. The promise of realizing this value in a new domain naturally stirs up much excitement among optimistic observers of the Internet. At the same time, the eagerness to place hopes for community in a technical system flies in the face of an influential intellectual tradition of technology criticism. This eagerness seems even more naive in the light of the recent commercialization of so much Internet activity. Despite the widespread skepticism, we believe the growth of virtual community is significant for an inquiry into the democratization of technology. We show that conflicting answers to the central question of the present theoretical debate - Is community possible on computer networks? epsilon neralize from particular features of systems and software prevalent at different stages in the development of computer networking. We conclude that research should focus instead on how to design computer networks to better support community activities and values

community technology
democratic rationalization
human agency
democratic process
technical sphere
virtual community
stable long-term group associations
human development
human value
diverse ideologies
optimistic observers
technical system
intellectual tradition
technology criticism
Internet activity
conflicting answers
computer networks
computer networking
community activities


Improved detection of lung nodules by using a temporal subtraction technique

Abstract: The authors evaluated the effect of a temporal subtraction technique for digital chest radiography with regard to the accuracy of detection of lung nodules. Twenty solitary lung nodules smaller than 30 mm in diameter, including 10 lung cancers and 10 benign nodules, were used. The nodules were grouped subjectively according to their subtlety. For nonnodular cases, 20 nodules without perceptible interval changes were selected. All chest radiographs were obtained by using a computed radiographic system, and temporal subtraction images were produced by using a program developed at the University of Chicago. The effect of the temporal subtraction image was evaluated by using an observer performance study, with use of receiver operating characteristic analysis. Observer performance with temporal subtraction images was substantially improved (A/sub z/ = 0.980 and 0.958), as compared with that without temporal subtraction images (A/sub z/ = 0.920 and 0.825) for the certified radiologists and radiology residents, respectively. The temporal subtraction technique clearly improved diagnostic accuracy for detecting lung nodules, especially subtle cases. In conclusion, the temporal subtraction technique is useful for improving detection accuracy for peripheral lung nodules on digital chest radiographs

improved lung nodules detection
temporal subtraction technique
digital chest radiography
perceptible interval changes
observer performance
peripheral lung nodules
radiology residents
certified radiologists
subtle cases
University of Chicago
computed radiographic system
medical diagnostic imaging
30 mm


A scalable model of cerebellar adaptive timing and sequencing: the recurrent slide and latch (RSL) model

Abstract: From the dawn of modern neural network theory, the mammalian cerebellum has been a favored object of mathematical modeling studies. Early studies focused on the fanout, convergence, thresholding, and learned weighting of perceptual-motor signals within the cerebellar cortex. This led to the still viable idea that the granule cell stage in the cerebellar cortex performs a sparse expansive recoding of the time-varying input vector. This recoding reveals and emphasizes combinations in a distributed representation that serves as a basis for the learned, state-dependent control actions engendered by cerebellar outputs to movement related centers. To make optimal use of available signals, the cerebellum must be able to sift the evolving state representation for the most reliable predictors of the need for control actions, and to use those predictors even if they appear only transiently and well in advance of the optimal time for initiating the control action. The paper proposes a modification to prior, population, models for cerebellar adaptive timing and sequencing. Since it replaces a population with a single element, the proposed RSL model is in one sense maximally efficient, and therefore optimal from the perspective of scalability

scalable model
cerebellar adaptive timing
cerebellar sequencing
recurrent slide and latch model
neural network theory
mammalian cerebellum
granule cell stage
sparse expansive recoding
time-varying input vector
distributed representation
recurrent network


A static semantics for Haskell

Abstract: This paper gives a static semantics for Haskell 98, a non-strict purely functional programming language. The semantics formally specifies nearly all the details of the Haskell 98 type system, including the resolution of overloading, kind inference (including defaulting) and polymorphic recursion, the only major omission being a proper treatment of ambiguous overloading and its resolution. Overloading is translated into explicit dictionary passing, as in all current implementations of Haskell. The target language of this translation is a variant of the Girard-Reynolds polymorphic lambda calculus featuring higher order polymorphism. and explicit type abstraction and application in the term language. Translated programs can thus still be type checked, although the implicit version of this system is impredicative. A surprising result of this formalization effort is that the monomorphism restriction, when rendered in a system of inference rules, compromises the principal type property

nonstrict purely functional programming language


Vector algebra proofs for geometry theorems

Abstract: Vector mathematics can generate simple and powerful proofs of theorems in plane geometry. These proofs can also be used to generalize plane geometry theorems to higher dimensions. We present three vector proofs that show the power of this technique. 1. For any quadrilateral, the sum of the squares of the diagonals is less than or equal to the sum of the squares of the sides. 2. The area of a quadrilateral is half the product of the diagonals multiplied by the sine of an included angle. 3. One quarter of all triangles are acute (Based upon the options detailed below, with respect to the relative lengths of the sides). This paper presents a set of examples of vector mathematics applied to geometry problems. Some of the most beautiful and sophisticated proofs in mathematics involve using multiple representations of the same data. By leveraging the advantages of each representation one finds new and useful mathematical facts

vector mathematics
plane geometry
multiple representations
quadrilateral
proofs
vector algebra proofs


Second term [International Telecommunication Union]

Abstract: Later this month Yoshio Utsumi is expected to be re-elected for a second four year term as secretary general of the International Telecommunication Union. Here he talks to Matthew May about getting involved in internet addressing, the prospects for 3g, the need for further reform of his organisation... and the translating telephone

International Telecommunication Union
internet addressing
translating telephone
3G


Dynamic spectrum management for next-generation DSL systems

Abstract: The performance of DSL systems is severely constrained by crosstalk due to the electromagnetic coupling among the multiple twisted pairs making up a phone cable. In order to reduce performance loss arising from crosstalk, DSL systems are currently designed under the assumption of worst-case crosstalk scenarios leading to overly conservative DSL deployments. This article presents a new paradigm for DSL system design, which takes into account the multi-user aspects of the DSL transmission environment. Dynamic spectrum management (DSM) departs from the current design philosophy by enabling transceivers to autonomously and dynamically optimize their communication settings with respect to both the channel and the transmissions of neighboring systems. Along with this distributed optimization, when an additional degree of coordination becomes available for future DSL deployment, DSM will allow even greater improvement in DSL performance. Implementations are readily applicable without causing any performance degradation to the existing DSLs under static spectrum management. After providing an overview of the DSM concept, this article reviews two practical DSM methods: iterative water-filling, an autonomous distributed power control method enabling great improvement in performance, which can be implemented through software options in some existing ADSL and VDSL systems; and vectored-DMT, a coordinated transmission/reception technique achieving crosstalk-free communication for DSL systems, which brings within reach the dream of providing universal Internet access at speeds close to 100 Mb/s to 500 m on 1-2 lines and beyond 1 km on 2-4 lines. DSM-capable DSL thus enables the broadband age


Elastically adaptive deformable models

Abstract: We present a technique for the automatic adaptation of a deformable model's elastic parameters within a Kalman filter framework for shape estimation applications. The novelty of the technique is that the model's elastic parameters are not constant, but spatio-temporally varying. The variation of the elastic parameters depends on the distance of the model from the data and the rate of change of this distance. Each pass of the algorithm uses physics-based modeling techniques to iteratively adjust both the geometric and the elastic degrees of freedom of the model in response to forces that are computed from the discrepancy between the model and the data. By augmenting the state equations of an extended Kalman filter to incorporate these additional variables, we are able to significantly improve the quality of the shape estimation. Therefore, the model's elastic parameters are always initialized to the same value and they are subsequently modified depending on the data and the noise distribution. We present results demonstrating the effectiveness of our method for both two-dimensional and three-dimensional data

elastically adaptive deformable models
automatic adaptation
elastic parameters
Kalman filter framework
shape estimation
physics-based modeling techniques
geometric degrees of freedom
elastic degrees of freedom
state equations
extended Kalman filter


An exactly solvable random satisfiability problem

Abstract: We introduce a new model for the generation of random satisfiability problems. It is an extension of the hyper-SAT model of Ricci-Tersenghi, Weigt and Zecchina (2001), which is a variant of the famous K-SAT model: it is extended to q-state variables and relates to a different choice of the statistical ensemble. The model has an exactly solvable statistic: the critical exponents and scaling functions of the SAT/UNSAT transition are calculable at zero temperature, with no need of replicas, also with exact finite-size corrections. We also introduce an exact duality of the model, and show an analogy of thermodynamic properties with the random energy model of disordered spin system theory. Relations with error correcting codes are also discussed


The use of subtypes and stereotypes in the UML model

Abstract: Based on users' experiences of Version 1.3 of the Unified Modeling Language (UML) of the Object Management Group (OMG), a Request For Information in 1999 elicited several responses which were asked to identify "problems" but not to offer any solutions. One of these responses is examined for "problems" relating to the UML metamodel and here some solutions to the problems identified there are proposed. Specifically, we evaluate the metamodel relating to stereotypes versus subtypes; the various kinds of Classifier (particularly Types, Interfaces and Classes); the introduction of a new subtype for the whole part relationship; as well as identifying areas in the metamodel where the UML seems to have been used inappropriately in the very definition of the UML's metamodel

subtypes
stereotypes
UML model
Unified Modeling Language
Object Management Group
Request For Information
Classifier
whole part relationship


Active vibration control of composite sandwich beams with piezoelectric extension-bending and shear actuators

Abstract: We have used quasi-static equations of piezoelectricity to derive a finite element formulation capable of modelling two different kinds of piezoelastically induced actuation in an adaptive composite sandwich beam. This formulation is made to couple certain piezoelectric constants to a transverse electric field to develop extension-bending actuation and shear-induced actuation. As an illustration, we present a sandwich model of three sublaminates: face/core/face. We develop a control scheme based on the linear quadratic regulator/independent modal space control (LQR/IMSC) method and use this to estimate the active stiffness and the active damping introduced by shear and extension-bending actuators. To assess the performance of each type of actuator, a dynamic response study is carried out in the modal domain. We observe that the shear actuator is more efficient in actively controlling the vibration than the extension-bending actuator for the same control effort

quasi-static equations
piezoelectricity
finite element formulation
piezoelastically
adaptive composite sandwich beam
piezoelectric constants
transverse electric field
extension-bending actuation
finite element procedure
shear-induced actuation
sandwich model
sublaminates
linear quadratic regulator
modal space control
active stiffness
active damping
shear actuators
extension-bending actuators
dynamic response
modal domain


Extrapolation in Lie groups with approximated BCH-formula

Abstract: We present an extrapolation algorithm for the integration of differential equations in Lie groups which is a suitable generalization of the well-known GBS-algorithm for ODEs. Sufficiently accurate approximations to the BCH-formula are required to reach a given order. We give such approximations with a minimized number of commutators

Lie groups
approximated BCH-formula
differential equations
GBS-algorithm
geometric integration
extrapolation methods


An efficient DIPIE algorithm for CAD of electrostatically actuated MEMS devices

Abstract: Pull-in parameters are important properties of electrostatic actuators. Efficient and accurate analysis tools that can capture these parameters for different design geometries, are therefore essential. Current simulation tools approach the pull-in state by iteratively adjusting the voltage applied across the actuator electrodes. The convergence rate of this scheme gradually deteriorates as the pull-in state is approached. Moreover, the convergence is inconsistent and requires many mesh and accuracy refinements to assure reliable predictions. As a result, the design procedure of electrostatically actuated MEMS devices can be time-consuming. In this paper a novel Displacement Iteration Pull-In Extraction (DIPIE) scheme is presented. The DIPIE scheme is shown to converge consistently and far more rapidly than the Voltage Iterations (VI) scheme (>100 times faster!). The DIPIE scheme requires separate mechanical and electrostatic field solvers. Therefore, it can be easily implemented in existing MOEMS CAD packages. Moreover, using the DIPIE scheme, the pull-in parameters extraction can be performed in a fully automated mode, and no user input for search bounds is required

displacement iteration pull-in extraction scheme


A dynamic checkpoint scheduling scheme for fault tolerant distributed computing systems

Abstract: The selection of the optimal checkpointing interval has been a very critical issue in implementing checkpointing-recovery schemes for fault tolerant distributed systems. This paper presents a new scheme that allows a process to select the proper checkpointing interval dynamically. A process in the system evaluates the cost of checkpointing and possible rollback for each checkpointing interval and selects the proper time interval for the next checkpointing. Unlike the other schemes, the overhead incurred by both the checkpointing and rollback activities are considered for the cost evaluation, and the current communication pattern is reflected in the selection of the checkpointing interval. Moreover, the proposed scheme requires no extra message communication for the checkpointing interval selection and can easily be incorporated into the existing checkpointing coordination schemes

dynamic checkpoint scheduling scheme
fault tolerant computing
distributed computing systems
optimal checkpointing interval
rollback recovery
cost evaluation
communication pattern


Automating the compliance and supervision process

Abstract: New technology enables large broker/dealers to supervise and ensure compliance across multiple branches and managers

compliance
supervision
brokers
risk management


Influence of advertising expenses on the characteristics of functioning of an insurance company

Abstract: The basic characteristics of the functioning of an insurance company, including the average capital, ruin and survival probabilities, and the conditional time before ruin, are examined with allowance for advertising expenses

insurance company functioning characteristics


Yet some more complexity results for default logic

Abstract: We identify several new tractable subsets and several new intractable simple cases for reasoning in the propositional version of Reiter's default logic. The majority of our findings are related to brave reasoning. By making some intuitive observations, most classes that we identify can be derived quite easily from some subsets of default logic already known in the literature. Some of the subsets we discuss are subclasses of the so-called "extended logic programs". All the tractable subsets presented in this paper can be recognized in linear time

reasoning
default logic
complexity results
complexity classes
nonmonotonic reasoning
extended logic programs
tractable subsets


Setup cost and lead time reductions on stochastic inventory models with a service level constraint

Abstract: The stochastic inventory models analyzed in this paper explore the problem of lead time associated with setup cost reductions for the continuous review and periodic review inventory models. For these two models with a mixture of backorders and lost sales, we respectively assume that their mean and variance of the lead time demand and protection interval (i.e., lead time plus review period) demand are known, but their probability distributions are unknown. We develop a minimax distribution free procedure to find the optimal solution-for each case

setup cost reductions
lead time reductions
stochastic inventory models
service level constraint
continuous review inventory models
periodic review inventory models
backorders
lost sales
lead time demand
protection interval
probability distributions
minimax distribution free procedure


Modelling tomographic cone-beam projection data from a polyhedral phantom

Abstract: Analytical phantoms are used to generate projection data for testing reconstruction accuracy in computed axial tomography. A circular source locus (equivalent to rotating specimen with a fixed source) provides insufficient data for 'exact' reconstruction in cone-beam transmission tomography, thus phantom data are useful for studying the consequent errors and also for investigating alternative scanning loci and reconstruction techniques. We present an algorithm that can compute phantom cone-beam projection data from a phantom comprising geometrically defined polyhedra. Each polyhedron is defined as a set of polygons enclosing a volume of fixed linear attenuation coefficient. The algorithm works by projecting each polygon in turn onto the modelled detector array, which accumulates the product of source to polygon intersection distance (for the rays intersecting each detector element), linear attenuation coefficient and sign of projected polygon area (indicating whether rays enter or exit the polyhedron at this face). The phantom data are rotated according to the projection angle, whilst the source location and detector plane remain fixed. Polyhedra can be of simple geometric form, or complex surfaces derived from 3D images of real specimens. This algorithm is illustrated using a phantom comprising 989 238 polygons, representing an iso-surface generated from a microtomographic reconstruction of a piece of walrus tusk

tomographic cone-beam projection data
polyhedral phantom
reconstruction accuracy
computed axial tomography
cone-beam transmission tomography
alternative scanning loci
geometrically defined polyhedra
linear attenuation coefficient
microtomographic reconstruction
walrus tusk
reconstruction software accuracy
X-ray attenuation
cumulative pixel array
interpolation
geometry file


On Implicit Euler for high-order high-index DAEs

Abstract: The Implicit Euler method is seldom used to solve differential-algebraic equations (DAEs) of differential index r >or= 3, since the method in general fails to converge in the first r - 2 steps after a change of stepsize. However, if the differential equation is of order d = r - 1 >or= 1, an alternative variable-step version of the Euler method can be shown uniformly convergent. For d = r - 1, this variable-step method is equivalent to the Implicit Euler except for the first r - 2 steps after a change of stepsize. Generalization to DAEs with differential equations of order d > r - 1 >or= 1, and to variable-order formulas is discussed

Implicit Euler method
differential-algebraic equations
convergence
stepsize change
variable-step method
variable-order formulas
linear multistep method
backward differentiation formula
initial value problem
differential index


An overview of modems

Abstract: This paper describes cursory glance of different types of modems classified for application, range, line type, operating mode, synchronizing mode, modulation, etc., highly useful for all engineering students of communication, electrical, computer science and information technology students. This paper also describes the standards and protocols used and the future trend

modems
line type
operating mode
synchronizing mode
modulation
engineering students
communication students
electrical students
computer science students
information technology students
standards
protocols


Sensitivity calibration of ultrasonic detectors based using ADD diagrams

Abstract: The paper considers basic problems related to utilization of ADD diagrams in calibrating sensitivity of ultrasonic detectors. We suggest that a convenient tool for solving such problems can be the software package ADD Universal. Version 2.1 designed for plotting individual ADD diagrams for normal and slanted transducers. The software is compatible with the contemporary operational system Windows-95(98). Reference signals for calibration are generated in a sample with cylindrical holes


Indexing-neglected and poorly understood

Abstract: The growth of the Internet has highlighted the use of machine indexing. The difficulties in using the Internet as a searching device can be frustrating. The use of the term "python" is given as an example. Machine indexing is noted as "rotten" and human indexing as "capricious." The problem seems to be a lack of a theoretical foundation for the art of indexing. What librarians have learned over the last hundred years has yet to yield a consistent approach to what really works best in preparing index terms and in the ability of our customers to search the various indexes. An attempt is made to consider the elements of indexing, their pros and cons. The argument is made that machine indexing is far too prolific in its production of index terms. Neither librarians nor computer programmers have made much progress to improve Internet indexing. Human indexing has had the same problems for over fifty years

Internet
machine indexing
searching
index terms
human indexing


The MAGNeT toolkit: design, implementation and evaluation

Abstract: The current trend in constructing high-performance computing systems is to connect a large number of machines via a fast interconnect or a large-scale network such as the Internet. This approach relies on the performance of the interconnect (or Internet) to enable fast, large-scale distributed computing. A detailed understanding of the communication traffic is required in order to optimize the operation of the entire system. Network researchers traditionally monitor traffic in the network to gain the insight necessary to optimize network operations. Recent work suggests additional insight can be obtained by also monitoring traffic at the application level. The Monitor for Application-Generated Network Traffic toolkit (MAGNeT) we describe here monitors application traffic patterns in production systems, thus enabling more highly optimized networks and interconnects for the next generation of high-performance computing systems


HPF/JA: extensions of High Performance Fortran for accelerating real-world applications

Abstract: This paper presents a set of extensions on High Performance Fortran (HPF) to make it more usable for parallelizing real-world production codes. HPF has been effective for programs that a compiler can automatically optimize efficiently. However, once the compiler cannot, there have been no ways for the users to explicitly parallelize or optimize their programs. In order to resolve the situation, we have developed a set of HPF extensions (HPF/JA) to give the users more control over sophisticated parallelization and communication optimizations. They include parallelization of loops with complicated reductions, asynchronous communication, user-controllable shadow, and communication pattern reuse for irregular remote data accesses. Preliminary experiments have proved that the extensions are effective at increasing HPF's usability

High Performance Fortran
HPF
parallel processing
compiler
data parallel language
supercomputer
parallelization of loops
parallel programming


Gearing up for CLS bank

Abstract: Continuous-Linked Settlement, a dream of the foreign-exchange community for years, may finally become a reality by the end of 2002


Local activity criteria for discrete-map CNN

Abstract: Discrete-time CNN systems are studied in this paper by the application of Chua's local activity principle. These systems are locally active everywhere except for one isolated parameter value. As a result, nonhomogeneous spatiotemporal patterns may be induced by any initial setting of the CNN system when the strength of the system diffusion coupling exceeds a critical threshold. The critical coupling coefficient can be derived from the loaded cell impedance of the CNN system. Three well-known 1D map CNN's (namely, the logistic map CNN, the magnetic vortex pinning map CNN, and the spiral wave reproducing map CNN) are introduced to illustrate the applications of the local activity principle. In addition, we use the cell impedance to demonstrate the period-doubling scenario in the logistic and the magnetic vortex pinning maps

discrete-time CNN systems
local activity criteria
difference equation
discrete-map CNN
loaded cell impedance
Chua's local activity principle
nonhomogeneous spatiotemporal patterns
critical coupling coefficient
logistic map CNN
magnetic vortex pinning map CNN
spiral wave reproducing map CNN
period-doubling


Anatomy of the coupling query in a Web warehouse

Abstract: To populate a data warehouse specifically designed for Web data, i.e. Web warehouse, it is imperative to harness relevant documents from the Web. In this paper, we describe a query mechanism called coupling query to glean relevant Web data in the context of our Web warehousing system called Warehouse Of Web Data (WHOWEDA). A coupling query may be used for querying both HTML and XML documents. Important features of our query mechanism are the ability to query metadata, content, internal and external (hyperlink) structure of Web documents based on partial knowledge, ability to express constraints on tag attributes and tagless segment of data, ability to express conjunctive as well as disjunctive query conditions compactly, ability to control execution of a Web query and preservation of the topological structure of hyperlinked documents in the query results. We also discuss how to formulate a query graphically and in textual form using a coupling graph and coupling text, respectively

coupling query
Web warehouse
data warehouse
Warehouse Of Web Data
HTML documents
XML documents
metadata
content
internal structure
external structure
Web documents
partial knowledge
tag attributes
tagless segment
disjunctive query conditions
conjunctive query conditions
execution control
topological structure
hyperlinked documents
graphical query formulation
textual query formulation
coupling text


A knowledge-navigation system for dimensional metrology

Abstract: Geometric dimensioning and tolerancing (GD&T) is a method to specify the dimensions and form of a part so that it will meet its design intent. GD&T is difficult to master for two main reasons. First, it is based on complex 3D geometric entities and relationships. Second, the geometry is associated with a large, diverse knowledge base of dimensional metrology with many interconnections. This paper describes an approach to create a dimensional metrology knowledge base that is organized around a set of key concepts and to represent those concepts as virtual objects that can be navigated with interactive, computer visualization techniques to access the associated knowledge. The approach can enable several applications. First is the application to convey the definition and meaning of GD&T over a broad range of tolerance types. Second is the application to provide a visualization of dimensional metrology knowledge within a control hierarchy of the inspection process. Third is the application to show the coverage of interoperability standards to enable industry to make decisions on standards development and harmonization efforts. A prototype system has been implemented to demonstrate the principles involved in the approach

geometric dimensioning
tolerancing
dimensional metrology
visualization
knowledge navigation
manufacturing training
VRML
interoperability standards
inspection
Web


Fast and accurate leaf verification for dynamic multileaf collimation using an electronic portal imaging device

Abstract: A prerequisite for accurate dose delivery of IMRT profiles produced with dynamic multileaf collimation (DMLC) is highly accurate leaf positioning. In our institution, leaf verification for DMLC was initially done with film and ionization chamber. To overcome the limitations of these methods, a fast, accurate and two-dimensional method for daily leaf verification, using our CCD-camera based electronic portal imaging device (EPID), has been developed. This method is based on a flat field produced with a 0.5 cm wide sliding gap for each leaf pair. Deviations in gap widths are detected as deviations in gray scale value profiles derived from the EPID images, and not by directly assessing leaf positions in the images. Dedicated software was developed to reduce the noise level in the low signal images produced with the narrow gaps. The accuracy of this quality assurance procedure was tested by introducing known leaf position errors. It was shown that errors in leaf gap as small as 0.01-0.02 cm could be detected, which is certainly adequate to guarantee accurate dose delivery of DMLC treatments, even for strongly modulated beam profiles. Using this method, it was demonstrated that both short and long term reproducibility in leaf positioning were within 0.01 cm (1 sigma ) for all gantry angles, and that the effect of gravity was negligible

intensity modulated radiation therapy profiles


UPSILON: universal programming system with incomplete lazy object notation

Abstract: This paper presents a new model of computation that differs from prior models in that it emphasizes data over flow control, has no named variables and has an object-oriented flavor. We prove that this model is a complete and confluent acceptable programming system and has a usable type theory. A new data synchronization primitive is introduced in order to achieve the above properties. Subtle variations of the model are shown to fall short of having all these necessary properties

UPSILON
universal programming system
object-oriented flavor
programming system
usable type theory
data synchronization primitive
incomplete lazy object notation


Lifting factorization of discrete W transform

Abstract: A general method is proposed to factor the type-IV discrete W transform (DWT-IV) into lifting steps and additions. Then, based on the relationships among various types of DWTs, four types of DWTs are factored into lifting steps and additions. After approximating the lifting matrices, we get four types of new integer DWTs (IntDWT-I, IntDWT-II, IntDWT-III, and IntDWT-IV) which are floating-point multiplication free. Integer-to-integer transforms (II-DWT), which approximate to DWT, are also proposed. Fast algorithms are given for the new transforms and their computational complexities are analyzed

lifting factorization
discrete wavelet transform
DWT
lifting matrices
integer transforms
computational complexity
data compression
feature extraction
multiframe detection
filter bank
lossless coding schemes
mobile devices
integer arithmetic
mobile computing


Optimization of the memory weighting function in stochastic functional self-organized sorting performed by a team of autonomous mobile agents

Abstract: The activity of a team of autonomous mobile agents formed by identical "robot-like-ant" individuals capable of performing a random walk through an environment that are able to recognize and move different "objects" is modeled. The emergent desired behavior is a distributed sorting and clustering based only on local information and a memory register that records the past objects encountered. An optimum weighting function for the memory registers is theoretically derived. The optimum time-dependent weighting function allows sorting and clustering of the randomly distributed objects in the shortest time. By maximizing the average speed of a texture feature (the contrast) we check the central assumption, the intermediate steady-states hypothesis, of our theoretical result. It is proved that the algorithm optimization based on maximum speed variation of the contrast feature gives relationships similar to the theoretically derived annealing law

autonomous mobile agents
random walk
memory weighting function
sorting
clustering
algorithm optimization


Quantum Zeno subspaces

Abstract: The quantum Zeno effect is recast in terms of an adiabatic theorem when the measurement is described as the dynamical coupling to another quantum system that plays the role of apparatus. A few significant examples are proposed and their practical relevance discussed. We also focus on decoherence-free subspaces

quantum Zeno subspaces
adiabatic theorem
dynamical coupling
measurement
decoherence-free subspaces


Testing statistical bounds on entanglement using quantum chaos

Abstract: Previous results indicate that while chaos can lead to substantial entropy production, thereby maximizing dynamical entanglement, this still falls short of maximality. Random matrix theory modeling of composite quantum systems, investigated recently, entails a universal distribution of the eigenvalues of the reduced density matrices. We demonstrate that these distributions are realized in quantized chaotic systems by using a model of two coupled and kicked tops. We derive an explicit statistical universal bound on entanglement, which is also valid for the case of unequal dimensionality of the Hilbert spaces involved, and show that this describes well the bounds observed using composite quantized chaotic systems such as coupled tops

statistical bounds
entanglement
quantum chaos
entropy production
maximality
random matrix theory
composite quantum systems
universal distribution
reduced density matrices
quantized chaotic systems
kicked tops
Hilbert spaces


An automated irradiation device for use in cyclotrons

Abstract: Two cyclotrons are being operated at IPEN-CNEN/SP: one model CV-28, capable of accelerating protons with energies up to 24 MeV and beam currents up to 30 mu A, and three other particles; the other one, model Cyclone 30, accelerates protons with energy of 30 MeV and currents up to 350 mu A. Both have the objective of irradiating targets both for radioisotope production for use in nuclear medicine and general research. The development of irradiating systems completely automatized was the objective of this work, always aiming to reduce the radiation exposition dose to the workers and to increase the reliability of use of these systems

automated irradiation device
cyclotrons
CV-28
protons
Cyclone 30
radioisotope production
nuclear medicine
general research
radiation exposition dose


Mathematical models of functioning of an insurance company with allowance for the rate of return

Abstract: Models of the functioning of insurance companies are suggested, when the free capital increases from interest at a certain rate. The basic characteristics of the capital of a company are studied in the stationary regime

mathematical models
insurance company functioning
return rate allowance
free capital increase
interest
stationary regime


Approximation theory of fuzzy systems based upon genuine many-valued implications - SISO cases

Abstract: It is proved that the single input and single output (SISO) fuzzy systems based upon genuine many-valued implications are universal approximators. It is shown theoretically that fuzzy control systems based upon genuine many-valued implications are equivalent to those based upon t-norm implications, the general approach to construct fuzzy systems is given. It is also shown that defuzzifier based upon center of areas is not appropriate to the fuzzy systems based upon genuine many-valued implications

single input and single output fuzzy systems


Does social capital determine innovation? To what extent?

Abstract: This paper deals with two questions: Does social capital determine innovation in manufacturing firms? If it is the case, to what extent? To deal with these questions, we review the literature on innovation in order to see how social capital came to be added to the other forms of capital as an explanatory variable of innovation. In doing so, we have been led to follow the dominating view of the literature on social capital and innovation which claims that social capital cannot be captured through a single indicator, but that it actually takes many different forms that must be accounted for. Therefore, to the traditional explanatory variables of innovation, we have added five forms of structural social capital (business network assets, information network assets, research network assets, participation assets, and relational assets) and one form of cognitive social capital (reciprocal trust). In a context where empirical investigations regarding the relations between social capital and innovation are still scanty, this paper makes contributions to the advancement of knowledge in providing new evidence regarding the impact and the extent of social capital on innovation at the two decisionmaking stages considered in this study

innovation
manufacturing firms
business network assets
information network assets
research network assets
participation assets
relational assets
cognitive social capital
structural social capital
reciprocal trust
two-stage decision-making process
degree of radicalness


Controls help harmonic spray do OK removing residues

Abstract: Looks at how innovative wafer-cleaning equipment hit the market in a timely fashion thanks in part to controls maker Rockwell Automation

Allen-Bradley ControlLogix automation control platform

Allen-Bradley 1336 Plus II variable frequency ac drives


Recruiting and retaining women in undergraduate computing majors

Abstract: This paper recommends methods for increasing female participation in undergraduate computer science. The recommendations are based on recent and on-going research into the gender gap in computer science and related disciplines. They are intended to work in tandem with the Computing Research Association's recommendations for graduate programs to promote a general increase in women's participation in computing professions. Most of the suggestions offered could improve the educational environment for both male and female students. However, general improvements are likely to be of particular benefit to women because women in our society do not generally receive the same level of support that men receive for entering and persisting in this field

undergraduate computing majors
women retention
women recruitment
female participation
gender gap
computer science


Heuristics for single-pass welding task sequencing

Abstract: Welding task sequencing is a prerequisite in the offline programming of robot arc welding. Single-pass welding task sequencing can be modelled as a modified travelling salesman problem. Owing to the difficulty of the resulting arc-routing problems, effective local search heuristics are developed. Computational speed becomes important because robot arc welding is often part of an automated process-planning procedure. Generating a reasonable solution in an acceptable time is necessary for effective automated process planning. Several different heuristics are proposed for solving the welding task-sequencing problem considering both productivity and the potential for welding distortion. Constructive heuristics based on the nearest neighbour concept and tabu search heuristics are developed and enhanced using improvement procedures. The effectiveness of the heuristics developed is tested and verified on actual welded structure problems and random problems

single-pass welding task sequencing
constructive heuristics
offline programming
robot arc welding
modified travelling salesman problem
local search heuristics
computational speed
automated process-planning procedure
productivity
welding distortion
nearest neighbour concept
tabu search heuristics
random problems
welded structure problems


Verona Lastre: consolidation provides opening for a new plate vendor

Abstract: Fewer companies than ever are manufacturing CTP plates. The market has become globalized, with just four big firms dominating the picture. To the Samor Group, however, globalization looked like an opportunity; it reasoned that many a national and local distributor would welcome a small, competitive, regional manufacturer. A couple of years ago it formed a company, Verona Lastre, to exploit that opportunity. Now Vela, as it's familiarly called, has launched its line of high-quality thermal plates and is busily lining up dealers in Europe and the Americas


Topology-reducing surface simplification using a discrete solid representation

Abstract: This paper presents a new approach for generating coarse-level approximations of topologically complex models. Dramatic topology reduction is achieved by converting a 3D model to and from a volumetric representation. Our approach produces valid, error-bounded models and supports the creation of approximations that do not interpenetrate the original model, either being completely contained in the input solid or bounding it. Several simple to implement versions of our approach are presented and discussed. We show that these methods perform significantly better than other surface-based approaches when simplifying topologically-rich models such as scene parts and complex mechanical assemblies


The year of the racehorse [China Telecom]

Abstract: Does China really offer the telecoms industry a route out of the telecoms slump? According to the Chinese government it has yet to receive a single application from foreign companies looking to invest in the country's domestic telecoms sector since the country joined the World Trade Organisation

China
telecoms industry
foreign investment
China Telecom
China Netcom
China Unicorn


Fidelity of quantum teleportation through noisy channels

Abstract: We investigate quantum teleportation through noisy quantum channels by solving analytically and numerically a master equation in the Lindblad form. We calculate the fidelity as a function of decoherence rates and angles of a state to be teleported. It is found that the average fidelity and the range of states to be accurately teleported depend on types of noises acting on quantum channels. If the quantum channels are subject to isotropic noise, the average fidelity decays to 1/2, which is smaller than the best possible value of 2/3 obtained only by the classical communication. On the other hand, if the noisy quantum channel is modeled by a single Lindblad operator, the average fidelity is always greater than 2/3

fidelity
quantum teleportation
noisy quantum channels
analytical solution
numerical solution
quantum channels
classical communication
Lindblad operator
Alice
Bob
sender
recipient
dual classical channels
eigenstate
isotropic noise


Extracting straight road structure in urban environments using IKONOS satellite imagery

Abstract: We discuss a fully automatic technique for extracting roads in urban environments. The method has its bases in a vegetation mask derived from multispectral IKONOS data and in texture derived from panchromatic IKONOS data. These two techniques together are used to distinguish road pixels. We then move from individual pixels to an object-based representation that allows reasoning on a higher level. Recognition of individual segments and intersections and the relationships among them are used to determine underlying road structure and to then logically hypothesize the existence of additional road network components. We show results on an image of San Diego, California. The object-based processing component may be adapted to utilize other basis techniques as well, and could be used to build a road network in any scene having a straight-line structured topology

straight road structure
urban environments
IKONOS satellite imagery
fully automatic technique
vegetation mask
texture
panchromatic IKONOS data
road pixels
object-based representation
higher level reasoning
individual segment recognition
road network components
San Diego
object-based processing component
straight-line structured topology
high-resolution imagery
large-scale feature extraction
vectorized road network


IT security issues: the need for end user oriented research

Abstract: Considerable attention has been given to the technical and policy issues involved with IT security issues in recent years. The growth of e-commerce and the Internet, as well as widely publicized hacker attacks, have brought IT security into prominent focus and routine corporate attention. Yet, much more research is needed from the end user (EU) perspective. This position paper is a call for such research and outlines some possible directions of interest

IT security
end user oriented research
e-commerce
Internet
hacker attacks
information technology research
end user computing


A formal framework for viewpoint consistency

Abstract: Multiple viewpoint models of system development are becoming increasingly important. Each viewpoint offers a different perspective on the target system and system development involves parallel refinement of the multiple views. Viewpoint related approaches have been considered in a number of different guises by a spectrum of researchers. Our work particularly focuses on the use of viewpoints in open distributed processing (ODP) which is an ISO/ITU standardisation framework. The requirements of viewpoint modelling in ODP are very broad and, hence, demanding. Multiple viewpoints, though, prompt the issue of consistency between viewpoints. This paper describes a very general interpretation of consistency which we argue is broad enough to meet the requirements of consistency in ODP. We present a formal framework for this general interpretation; highlight basic properties of the interpretation and locate restricted classes of consistency. Strategies for checking consistency are also investigated. Throughout we illustrate our theory using the formal description technique LOTOS. Thus, the paper also characterises the nature of and options for consistency checking in LOTOS

multiple viewpoint models
formal framework
viewpoint consistency
system development
open distributed processing
ODP
ISO/ITU standardisation framework
consistency checking
formal description technique
LOTOS
development models
process algebra


Modular and visual specification of hybrid systems: an introduction to HyCharts

Abstract: Visual description techniques are particularly important for the design of hybrid systems, because specifications of such systems usually have to be discussed between engineers from a number of different disciplines. Modularity is vital for hybrid systems not only because it allows to handle large systems, but also because it permits to think in terms of components, which is familiar to engineers. Based on two different interpretations for hierarchic graphs and on a clear hybrid computation model, we develop HyCharts. HyCharts consist of two modular visual formalisms, one for the specification of the architecture and one for the specification of the behavior of hybrid systems. The operators on hierarchic graphs enable us to give a surprisingly simple denotational semantics for many concepts known from statechart-like formalisms. Due to a very general composition operator, HyCharts can easily be composed with description techniques from other engineering disciplines. Such heterogeneous system specifications seem to be particularly appropriate for hybrid systems because of their interdisciplinary character

visual specification
modular specification
hybrid systems
HyCharts
visual description techniques
components
hierarchic graphs
hybrid computation model
denotational semantics
statechart
heterogeneous system specifications
formal specification


Dynamic testing of inflatable structures using smart materials

Abstract: In this paper we present experimental investigations of the vibration testing of an inflated, thin-film torus using smart materials. Lightweight, inflatable structures are very attractive in satellite applications. However, the lightweight, flexible and highly damped nature of inflated structures poses difficulties in ground vibration testing. In this study, we show that polyvinylidene fluoride (PVDF) patches and recently developed macro-fiber composite actuators may be used as sensors and actuators in identifying modal parameters. Both smart materials can be integrated unobtrusively into the skin of a torus or space device forming an attractive testing arrangement. The addition of actuators and PVDF sensors to the torus does not significantly interfere with the suspension modes of a free-free boundary condition, and can be considered an integral part of the inflated structure. The results indicate the potential of using smart materials to measure and control the dynamic response of inflated structures

thin-film torus
smart materials
satellite applications
inflated structures
ground vibration testing
polyvinylidene fluoride patches
PVDF sensors
macro-fiber composite actuators
modal parameters
space device
boundary condition
dynamic response
Kapton torus


A suggestion of fractional-order controller for flexible spacecraft attitude control

Abstract: A controller design method for flexible spacecraft attitude control is proposed. The system is first described by a partial differential equation with internal damping. Then the frequency response is analyzed, and the three basic characteristics of the flexible system, namely, average function, lower bound and upper bound are defined. On this basis, a fractional-order controller is proposed, which functions as phase stabilization control for lower frequency and smoothly enters to amplitude stabilization at higher frequency by proper amplitude attenuation. It is shown that the equivalent damping ratio increases in proportion to the square of frequency

fractional-order controller
flexible spacecraft attitude control
partial differential equation
internal damping
frequency response
phase stabilization control
amplitude stabilization
damping ratio


Lob's theorem as a limitation on mechanism

Abstract: We argue that Lob's Theorem implies a limitation on mechanism. Specifically, we argue, via an application of a generalized version of Lob's Theorem, that any particular device known by an observer to be mechanical cannot be used as an epistemic authority (of a particular type) by that observer: either the belief-set of such an authority is not mechanizable or, if it is, there is no identifiable formal system of which the observer can know (or truly believe) it to be the theorem-set. This gives, we believe, an important and hitherto unnoticed connection between mechanism and the use of authorities by human-like epistemic agents

Lob Theorem
limitation on mechanism
epistemic authority
belief-set
formal system
theorem-set
human-like epistemic agents


Is diversity in computing a moral matter?

Abstract: We have presented an ethical argument that takes into consideration the subtleties of the issue surrounding under-representation in computing. We should emphasize that there is nothing subtle about overt, unfair discrimination. Where such injustice occurs, we condemn it. Our concern is that discrimination need not be explicit or overt. It need not be individual-to-individual. Rather, it can be subtly built into social practices and social institutions. Our analysis raises ethical questions about aspects of computing that drive women away, aspects that can be changed in ways that improve the profession and access to the profession. We hope that computing will move towards these improvements

ethical argument
computing under-representation
unfair discrimination
social practices
social institutions
women


A maximum-likelihood surface estimator for dense range data

Abstract: Describes how to estimate 3D surface models from dense sets of noisy range data taken from different points of view, i.e., multiple range maps. The proposed method uses a sensor model to develop an expression for the likelihood of a 3D surface, conditional on a set of noisy range measurements. Optimizing this likelihood with respect to the model parameters provides an unbiased and efficient estimator. The proposed numerical algorithms make this estimation computationally practical for a wide variety of circumstances. The results from this method compare favorably with state-of-the-art approaches that rely on the closest-point or perpendicular distance metric, a convenient heuristic that produces biased solutions and fails completely when surfaces are not sufficiently smooth, as in the case of complex scenes or noisy range measurements. Empirical results on both simulated and real ladar data demonstrate the effectiveness of the proposed method for several different types of problems. Furthermore, the proposed method offers a general framework that can accommodate extensions to include surface priors, more sophisticated noise models, and other sensing modalities, such as sonar or synthetic aperture radar

maximum-likelihood surface estimator
dense range data
3D surface models
noisy range data
sensor model
unbiased estimator
heuristic
biased solutions
complex scenes
noisy range measurements
simulated ladar data
real ladar data
sonar
synthetic aperture radar
surface reconstruction
surface fitting
optimal estimation
parameter estimation
Bayesian estimation
registration
calibration


Dynamics of the firing probability of noisy integrate-and-fire neurons

Abstract: Cortical neurons in vivo undergo a continuous bombardment due to synaptic activity, which acts as a major source of noise. We investigate the effects of the noise filtering by synapses with various levels of realism on integrate-and-fire neuron dynamics. The noise input is modeled by white (for instantaneous synapses) or colored (for synapses with a finite relaxation time) noise. Analytical results for the modulation of firing probability in response to an oscillatory input current are obtained by expanding a Fokker-Planck equation for small parameters of the problem-when both the amplitude of the modulation is small compared to the background firing rate and the synaptic time constant is small compared to the membrane time constant. We report the detailed calculations showing that if a synaptic decay time constant is included in the synaptic current model, the firing-rate modulation of the neuron due to an oscillatory input remains finite in the high-frequency limit with no phase lag. In addition, we characterize the low-frequency behavior and the behavior of the high-frequency limit for intermediate decay times. We also characterize the effects of introducing a rise time to the synaptic currents and the presence of several synaptic receptors with different kinetics. In both cases, we determine, using numerical simulations, an effective decay time constant that describes the neuronal response completely

firing probability
noisy integrate-and-fire neurons
cortical neurons
synaptic activity
noise filtering
white noise
colored noise
Fokker-Planck equation
synaptic time constant
membrane time constant
phase lag
synaptic receptors
numerical simulation


Ultrafast compound imaging for 2-D motion vector estimation: application to transient elastography

Abstract: This paper describes a new technique for two-dimensional (2-D) imaging of the motion vector at a very high frame rate with ultrasound. Its potential is experimentally demonstrated for transient elastography. But, beyond this application, it also could be promising for color flow and reflectivity imaging. To date, only axial displacements induced in human tissues by low-frequency vibrators were measured during transient elastography. The proposed technique allows us to follow both axial and lateral displacements during the shear wave propagation and thus should improve Young's modulus image reconstruction. The process is a combination of several ideas well-known in ultrasonic imaging: ultra-fast imaging, multisynthetic aperture beamforming, 1-D speckle tracking, and compound imaging. Classical beamforming in the transmit mode is replaced here by a single plane wave insonification increasing the frame rate by at least a factor of 128. The beamforming is achieved only in the receive mode on two independent subapertures. Comparison of successive frames by a classical 1-D speckle tracking algorithm allows estimation of displacements along two different directions linked to the subapertures beams. The variance of the estimates is finally improved by tilting the emitting plane wave at each insonification, thus allowing reception of successive decorrelated speckle patterns

ultrafast compound imaging
2D motion vector estimation
two-dimensional imaging
transient elastography
2D imaging
high frame rate
ultrasound
colour flow imaging
reflectivity imaging
human tissues
axial displacements
lateral displacements
shear wave propagation
Young's modulus image reconstruction
ultrasonic imaging
multisynthetic aperture beamforming
1D speckle tracking algorithm
decorrelated speckle patterns
single plane wave insonification


Waiting-time distribution of a discrete-time multiserver queue with correlated arrivals and deterministic service times: D-MAP/D/k system

Abstract: We derive the waiting-time distribution of a discrete-time multiserver queue with correlated arrivals and deterministic (or constant) service times. We show that the procedure for obtaining the waiting-time distribution of a multiserver queue is reduced to that of a single-server queue. We present a complete solution to the waiting-time distribution of D-MAP/D/k queue together with some computational results

waiting-time distribution
discrete-time multiserver queue
correlated arrivals
deterministic service times
D-MAP/D/k system
Markovian arrival process


Women in computing: what brings them to it, what keeps them in it?

Abstract: Career stereotyping and misperceptions about the nature of computing are substantive reasons for the under representation of women in professional computing careers. In this study, 15 women who have work experience in several aspects of computing were asked about their reasons for entering computing, what they liked about working in computing, and what they disliked. While there are many common threads, there are also individual differences. Common reasons for choosing computing as a career included: exposure to computing in a setting which enabled them to see the versatility of computers; the influence of someone close to them; personal abilities which they perceived to be appropriate for a career in computing; and characteristics of such careers which appealed to them. Generally, women working in the field enjoy the work they are doing. Dislikes arising from their work experiences are more likely to be associated with people and politics than with the work they do-and they would like to have more female colleagues

career stereotyping
personal abilities
politics
misperceptions
women
professional computing careers


Voltage control methods with grid connected wind turbines: a tutorial review

Abstract: Within electricity grid networks it is conventional for large-scale central generators to both provide power and control grid node voltage. Therefore when wind turbines replace conventional power stations on a substantial scale, they must not only generate power, but also control grid node voltages. This paper reviews the basic principles of voltage control for tutorial benefit and then considers application of grid-connected wind turbines for voltage control. The most widely used contemporary wind turbine types are considered and further detail is given for determining the range of variables that allow control

electricity grid networks
large-scale central generators
grid connected wind turbines
grid node voltages control
voltage control
reactive power
direct drive
variable speed
offshore wind park
squirrel cage induction generator
doubly fed induction generator
direct drive synchronous generator
weak grid
converter rating


Becoming a computer scientist

Abstract: The focus of this report is pipeline shrinkage for women in computer science. We describe the situation for women at all stages of training in computer science, from the precollege level through graduate school. Because many of the problems discussed are related to the lack of role models for women who are in the process of becoming computer scientists, we also concern ourselves with the status of women faculty members. We not only describe the problems, but also make specific recommendations for change and encourage further study of those problems whose solutions are not yet well understood

pipeline shrinkage
women
computer science
role models
women faculty members


Some recent advances in validated methods for IVPs for ODEs

Abstract: Compared to standard numerical methods for initial value problems (IVPs) for ordinary differential equations (ODEs), validated methods (often called interval methods) for IVPs for ODEs have two important advantages: if they return a solution to a problem, then (1) the problem is guaranteed to have a unique solution, and (2) an enclosure of the true solution is produced. We present a brief overview of interval Taylor series (ITS) methods for IVPs for ODEs and discuss some recent advances in the theory of validated methods for IVPs for ODEs. In particular, we discuss an interval Hermite-Obreschkoff (IHO) scheme for computing rigorous bounds on the solution of an IVP for an ODE, the stability of ITS and IHO methods, and a new perspective on the wrapping effect, where we interpret the problem of reducing the wrapping effect as one of finding a more stable scheme for advancing the solution

validated methods
initial value problems
ordinary differential equations
interval methods
interval Taylor series
interval Hermite-Obreschkoff scheme
wrapping effect
QR algorithm


A discontinuous Galerkin method for transient analysis of wave propagation in unbounded domains

Abstract: A technique based on the discontinuous Galerkin finite element method is developed and applied to the derivation of an absorbing boundary condition for the analysis of transient wave propagation. The condition is exact in that only discretization error is involved. Furthermore, the computational cost associated with use of the condition is an order of magnitude lower than for conditions based on Green functions. The time-stepping scheme resulting from an implicit method in conjunction with this boundary condition appears to be unconditionally stable


Arbortext: enabler of multichannel publishing

Abstract: A company has a document-say, dosage instructions for a prescription drug or a troubleshooting sheet for a DVD drive. That document starts its life in a predictable format, probably Microsoft Word or WordPerfect, but then-to meet the needs of readers who nowadays demand access via multiple devices-the material has to be translated into many more formats: HTML, PageMaker, or Quark, possibly RTF, almost certainly PDF, and nowadays, next-generation devices (cell phones, handheld computers) also impose their own requirements. And what if, suddenly, the dosage levels change or new workarounds emerge to handle DVD problems? That's when a company should put in a call to Arbortext, a 20-year-old Ann Arbor, Michigan-based company that exists to solve a single problem: helping clients automate multichannel publishing

document format
next-generation devices
Arbortext
multichannel publishing
content assets


Adaptive wavelet methods. II. Beyond the elliptic case

Abstract: This paper is concerned with the design and analysis of adaptive wavelet methods for systems of operator equations. Its main accomplishment is to extend the range of applicability of the adaptive wavelet-based method developed previously for symmetric positive definite problems to indefinite or unsymmetric systems of operator equations. This is accomplished by first introducing techniques (such as the least squares formulation developed previously) that transform the original (continuous) problem into an equivalent infinite system of equations which is now well-posed in the Euclidean metric. It is then shown how to utilize adaptive techniques to solve the resulting infinite system of equations. It is shown that for a wide range of problems, this new adaptive method performs with asymptotically optimal complexity, i.e., it recovers an approximate solution with desired accuracy at a computational expense that stays proportional to the number of terms in a corresponding wavelet-best N-term approximation. An important advantage of this adaptive approach is that it automatically stabilizes the numerical procedure so that, for instance, compatibility constraints on the choice of trial spaces, like the LBB condition, no longer arise

adaptive wavelet methods
elliptic case
operator equations
least squares formulation
Euclidean metric
asymptotically optimal complexity
N-term approximation


Application of Sugeno fuzzy-logic controller to the stator field-oriented doubly-fed asynchronous motor drive

Abstract: This study deals with the application of the fuzzy-control theory to wound-rotor asynchronous motor with both its stator and rotor fed by two PWM voltage-source inverters, in which the system operates in stator field-oriented control. Thus, after determining the model of the machine, we present two types of fuzzy controller: Mamdani and Sugeno controllers. The training of the last one is carried out starting from the first. Simulation study is conducted to show the effectiveness of the proposed method


A transactional asynchronous replication scheme for mobile database systems

Abstract: In mobile database systems, mobility of users has a significant impact on data replication. As a result, the various replica control protocols that exist today in traditional distributed and multidatabase environments are no longer suitable. To solve this problem, a new mobile database replication scheme, the Transaction-Level Result-Set Propagation (TLRSP) model, is put forward in this paper. The conflict detection and resolution strategy based on TLRSP is discussed in detail, and the implementation algorithm is proposed. In order to compare the performance of the TLRSP model with that of other mobile replication schemes, we have developed a detailed simulation model. Experimental results show that the TLRSP model provides an efficient support for replicated mobile database systems by reducing reprocessing overhead and maintaining database consistency


Embedding the outer automorphism group Out(F/sub n/) of a free group of rank n in the group Out(F/sub m/) for m > n

Abstract: It is proved that for every n >or= 1, the group Out(F/sub n/) is embedded in the group Out(F/sub m/) with m = 1 + (n - 1)k/sup n/, where k is an arbitrary natural number coprime to n - 1

outer automorphism group embedding
free group
arbitrary natural number coprime


Modelling dependencies in paired comparison data a log-linear approach

Abstract: In many Bradley-Terry models a more or less explicit assumption is that all decisions of the judges are independent. An assumption which might be questionable at least for the decisions of a given judge. In paired comparison studies, a judge chooses among objects several times, and in such cases, judgements made by the same judge are likely to be dependent. A log-linear representation for the Bradley-Terry model is developed, which takes into account dependencies between judgements. The modelling of the dependencies is embedded in the analysis of multiple binomial responses, which has the advantage of interpretability in terms of conditional odds ratios. Furthermore, the modelling is done in the framework of generalized linear models, thus parameter estimation and the assessment of goodness of fit can be obtained in the standard way by using e.g. GLIM or another standard software

paired comparison data dependency modelling


Acts to facts catalogue

Abstract: The paper shows a way to satisfy users' changing and specific information needs by providing the modified format-author-collaborators-title-series-subject (FACTS). catalogue instead of the traditional author-collaborator-title-series-subjects (ACTS) catalogue


Mining the optimal class association rule set

Abstract: We define an optimal class association rule set to be the minimum rule set with the same predictive power of the complete class association rule set. Using this rule set instead of the complete class association rule set we can avoid redundant computation that would otherwise be required for mining predictive association rules and hence improve the efficiency of the mining process significantly. We present an efficient algorithm for mining the optimal class association rule set using an upward closure property of pruning weak rules before they are actually generated. We have implemented the algorithm and our experimental results show that our algorithm generates the optimal class association rule set, whose size is smaller than 1/17 of the complete class association rule set on average, in significantly less time than generating the complete class association rule set. Our proposed criterion has been shown very effective for pruning weak rules in dense databases

optimal class association rule set mining


3D reconstruction from uncalibrated-camera optical flow and its reliability evaluation

Abstract: We present a scheme for reconstructing a 3D structure from optical flow observed by a camera with an unknown focal length in a statistically optimal way as well as evaluating the reliability of the computed shape. First, the flow fundamental matrices are optimally computed from the observed flow. They are then decomposed into the focal length, its rate of change, and the motion parameters. Next, the flow is optimally corrected so that it satisfies the epipolar equation exactly. Finally, the 3D positions are computed, and their covariance matrices are evaluated. By simulations and real-image experiments, we test the performance of our system and observe how the normalization (gauge) for removing indeterminacy affects the description of uncertainty

3D reconstruction
uncalibrated-camera optical flow
reliability evaluation
flow fundamental matrices
motion parameters
epipolar equation
covariance matrices
real-image experiments
normalization


Agents in e-commerce: state of the art

Abstract: This paper surveys the state of the art of agent-mediated electronic commerce (e-commerce), especially in business-to-consumer (B2C) e-commerce and business-to-business (B2B) e-commerce. From the consumer buying behaviour perspective, the roles of agents in B2C e-commerce are: product brokering, merchant brokering, and negotiation. The applications of agents in B2B e-commerce are mainly in supply chain management. Mobile agents, evolutionary agents, and data-mining agents are some special techniques which can be applied in agent-mediated e-commerce. In addition, some technologies for implementation are briefly reviewed. Finally, we conclude this paper by discussions on the future directions of agent-mediated e-commerce

state of the art
agent-mediated electronic commerce
business-to-consumer e-commerce
consumer buying behaviour
product brokering
merchant brokering
negotiation
supply chain management
multi-agent systems
mobile agents
evolutionary agents
data-mining agents
business-to-business e-commerce


Approximation and complexity. II. Iterated integration

Abstract: For pt. I. see ibid., no. 1, p. 289-95 (2001). We introduce two classes of real analytic functions W contained in/implied by U on an interval. Starting with rational functions to construct functions in W we allow the application of three types of operations: addition, integration, and multiplication by a polynomial with rational coefficients. In a similar way, to construct functions in U we allow integration, addition, and multiplication of functions already constructed in U and multiplication by rational numbers. Thus, U is a subring of the ring of Pfaffian functions. Two lower bounds on the L/sub infinity /-norm are proved on a function f from W (or from U, respectively) in terms of the complexity of constructing f

real analytic functions
rational functions
addition
integration
multiplication
polynomial
Pfaffian functions
lower bounds
L/sub infinity /-norm


Cache invalidation and replacement strategies for location-dependent data in mobile environments

Abstract: Mobile location-dependent information services (LDISs) have become increasingly popular in recent years. However, data caching strategies for LDISs have thus far received little attention. In this paper, we study the issues of cache invalidation and cache replacement for location-dependent data under a geometric location model. We introduce a new performance criterion, called caching efficiency, and propose a generic method for location-dependent cache invalidation strategies. In addition, two cache replacement policies, PA and PAID, are proposed. Unlike the conventional replacement policies, PA and PAID take into consideration the valid scope area of a data value. We conduct a series of simulation experiments to study the performance of the proposed caching schemes. The experimental results show that the proposed location-dependent invalidation scheme is very effective and the PA and PAID policies significantly outperform the conventional replacement policies

mobile location-dependent information services


A novel robot hand with embedded shape memory alloy actuators

Abstract: Describes the development of an active robot hand, which allows smooth and lifelike motions for anthropomorphic grasping and fine manipulations. An active robot finger 10 mm in outer diameter with a shape memory alloy (SMA) wire actuator embedded in the finger with a constant distance from the geometric centre of the finger was designed and fabricated. The practical specifications of the SMA wire and the flexible rod were determined on the basis of a series of formulae. The active finger consists of two bending parts, the SMA actuators and a connecting part. The mechanical properties of the bending part are investigated. The control system on the basis of resistance feedback is also presented. Finally, a robot hand with three fingers was designed and the grasping experiment was carried out to demonstrate its performance

embedded shape memory alloy actuators
lifelike motions
anthropomorphic grasping
fine manipulations
active finger
resistance feedback
flexible rod
active robot hand


Flow measurement - future directions

Abstract: Interest in the flow of liquids and its measurement can be traced back to early studies by the Egyptians, the Chinese and the Romans. Since these early times the science of flow measurement has undergone a massive change but during the last 25 years or so (1977-2002) it has matured enormously. One of the principal reasons for this is that higher accuracies and reliabilities have been demanded by industry in the measurement of fiscal transfers and today there is vigorous interest in the subject from both the flowmeter manufacturer and user viewpoints. This interest is coupled with the development of advanced computer techniques in fluid mechanics together with the application of increasingly sophisticated electronics

flow measurement
flow metering
signal processing
liquid flow
Egyptians
Chinese
Romans
fiscal transfers
flowmeter manufacturer
advanced computer techniques
fluid mechanics
electronics application


An ACM-W literature review on women in computing

Abstract: The pipeline shrinkage problem for women in computer science is a well-known and documented phenomenon where the ratio of women to men involved in computing shrinks dramatically from early student years to working years. During the last decade, considerable research ensued to understand the reasons behind the existence of the shrinking pipeline and in some cases to take action to increase the numbers of women in computing. Through the work of a National Science Foundation funded project, ACM's Committee on Women in Computing (ACM-W) has taken a first step towards pulling this research together. A large number of articles was gathered and processed on the topic of women in computing and the shrinking pipeline. The committee created a publicly available online database to organize the references of this body of work by topic, author, and reference information. The database, constantly being updated, is accessible through ACM-W's website <http://www.acm.org/women>. A final report is also available via the ACM-W Web site which covers current statistics on women in computing, summaries of the literature in the database, and a set of recommendations. The article is a brief synopsis of a subset of the literature review as of August 2001

ACM-W literature review
ACM Committee on Women in Computing
pipeline shrinkage problem


On quasi-linear PDAEs with convection: applications, indices, numerical solution

Abstract: For a class of partial differential algebraic equations (PDAEs) of quasi-linear type which include nonlinear terms of convection type, a possibility to determine a time and spatial index is considered. As a typical example we investigate an application from plasma physics. Especially we discuss the numerical solution of initial boundary value problems by means of a corresponding finite difference splitting procedure which is a modification of a well-known fractional step method coupled with a matrix factorization. The convergence of the numerical solution towards the exact solution of the corresponding initial boundary value problem is investigated. Some results of a numerical solution of the plasma PDAE are given

quasi-linear partial differential algebraic equations


A wizard idea [Internet in finance]

Abstract: New technology is set to become an ever-more important area of work for brokers. Lawrie Holmes looks at how the Internet is driving change and opportunity


WAM!Net: private pipes for electronic media

Abstract: "We are the digital version of FedEx. We offer storage and intelligent workflow." The United States military - especially during war time - is pretty careful about the way it handles its workflow and communications. Before a company is awarded a government contract, the company and its technology are screened and verified. If the technology or its creators aren't trustworthy and secure, chances are they aren't getting by Uncle Sam. Record companies and publishing houses tend to feel the same way. After all, security is just as important to a record executive as it is to a Navy commander. WAM!Net, a Wide-Area Media network (hence, the name) passes muster with both. The company, which employs about 320 employees around the world, has 15000 customers including the US Navy and a host of record labels, publishing companies, healthcare providers, and advertising agencies, all of whom use its network as a way to transport, store, and receive data. "We are the digital version of FedEx. We offer storage and intelligent workflow," says Murad Velani, executive vice president of sales and marketing for WAM!Net. "We started out as purely transport and we've become a digital platform."

United States military
Wide-Area Media network
U.S. Navy
record labels
publishing companies
healthcare providers
advertising agencies
intelligent workflow
WAM!Net
content creators
electronic media
high-speed private network
ATM technology
content information
publishing information
client-server format
ASP format
digital platform


Development of an Internet-based intelligent design support system for rolling element bearings

Abstract: This paper presents a novel approach to developing an intelligent agile design system for rolling bearings based on artificial intelligence (AI), Internet and Web technologies and expertise. The underlying philosophy of the approach is to use AI technology and Web-based design support systems as smart tools from which design customers can rapidly and responsively access the systems' built-in design expertise. The approach is described in detail with a novel AI model and system implementation issues. The major issues in implementing the approach are discussed with particular reference to using AI technologies, network programming, client-server technology and open computing of bearing design and manufacturing requirements


Critical lines identification on voltage collapse analysis

Abstract: This paper deals with critical lines identification on voltage collapse analysis. It is known, from the literature, that voltage collapse is a local phenomenon that spreads around an initial neighborhood Therefore, identifying the system critical bus plays an important role on voltage collapse prevention. For this purpose, the system critical transmission lines should also be identified In this paper, these issues are addressed, yielding reliable results in a short computational time. Tests are done with the help of the IEEE-118 bus and the Southeastern Brazilian systems

critical transmission lines identification


Quasi stage order conditions for SDIRK methods

Abstract: The stage order condition is a simplifying assumption that reduces the number of order conditions to be fulfilled when designing a Runge-Kutta (RK) method. Because a DIRK (diagonally implicit RK) method cannot have stage order greater than 1, we introduce quasi stage order conditions and derive some of their properties for DIRKs. We use these conditions to derive a low-order DIRK method with embedded error estimator. Numerical tests with stiff ODEs and DAEs of index 1 and 2 indicate that the method is competitive with other RK methods for low accuracy tolerances

quasi stage order conditions
diagonally implicit Runge-Kutta method
embedded error estimator
numerical tests
differential-algebraic systems
SDIRK methods


Hierarchical neuro-fuzzy quadtree models

Abstract: Hybrid neuro-fuzzy systems have been in evidence during the past few years, due to its attractive combination of the learning capacity of artificial neural networks with the interpretability of the fuzzy systems. This article proposes a new hybrid neuro-fuzzy model, named hierarchical neuro-fuzzy quadtree (HNFQ), which is based on a recursive partitioning method of the input space named quadtree. The article describes the architecture of this new model, presenting its basic cell and its learning algorithm. The HNFQ system is evaluated in three well known benchmark applications: the sinc(x, y) function approximation, the Mackey Glass chaotic series forecast and the two spirals problem. When compared to other neuro-fuzzy systems, the HNFQ exhibits competing results, with two major advantages it automatically creates its own structure and it is not limited to few input variables

neuro-fuzzy systems
fuzzy systems
hierarchical neuro-fuzzy quadtree
quadtree
recursive partitioning
learning algorithm
Mackey Glass chaotic series


Score tests for zero-inflated Poisson models

Abstract: In many situations count data have a large proportion of zeros and the zero-inflated Poisson regression (ZIP) model may be appropriate. A simple score test for zero-inflation, comparing the ZIP model with a constant proportion of excess zeros to a standard Poisson regression model, was given by van den Broek (1995). We extend this test to the more general situation where the zero probability is allowed to depend on covariates. The performance of this test is evaluated using a simulation study. To identify potentially important covariates in the zero-inflation model a composite test is proposed. The use of the general score test and the composite procedure is illustrated on two examples from the literature. The composite score test is found to suggest appropriate models

count data
score tests
zero-inflated Poisson regression model
zero probability
covariates
excess zeros
simulation
composite test


Application foundations [application servers]

Abstract: The changing role of application servers means choosing the right platform has become a complex challenge

application servers
Microsoft .Net
transaction processing
security
availability
load balancing
Java 2 Enterprise Edition


Modeling discourse in collaborative work support systems: a knowledge representation and configuration perspective

Abstract: Collaborative work processes usually raise a lot of intricate debates and negotiations among participants, whereas conflicts of interest are inevitable and support for achieving consensus and compromise is required. Individual contributions, brought up by parties with different backgrounds and interests, need to be appropriately structured and maintained. This paper presents a model of discourse acts that participants use to communicate their attitudes to each other, or affect the attitudes of others, in such environments. The first part deals with the knowledge representation and communication aspects of the problem, while the second one, in the context of an already implemented system, namely HERMES, with issues related to the configuration of the contributions asserted at each discourse instance. The overall work focuses on the machinery needed in a computer-assisted collaborative work environment, the aim being to further enhance the human-computer interaction

discourse modeling
collaborative work support systems
knowledge representation
conflicts of interest
consensus
compromise
knowledge communication
HERMES
human-computer interaction


Optimization of requantization parameter for MPEG transcoding

Abstract: This paper considers transcoding in which an MPEG stream is converted to a low-bit-rate MPEG stream, and proposes a method in which the transcoding error can be reduced by optimally selecting the quantization parameter for each macroblock. In transcoding with a low compression ratio, it is crucial to prohibit transcoding with a requantization parameter which is 1 to 2 times the quantization parameter of the input stream. Consequently, as the first step, an optimization method for the requantization parameter is proposed which cares for the error propagation effect by interframe prediction. Then, the proposed optimization method is extended so that the method can also be applied to the case of a high compression ratio in which the rate-distortion curve is approximated for each macroblock in the range of requantization parameters larger than 2 times the quantization parameter. It is verified by a simulation experiment that the PSNR is improved by 0.5 to 0.8 dB compared to the case in which a 6 Mbit/s MPEG stream is not optimized by twofold recompression

requantization parameter optimization
low-bit-rate MPEG stream
transcoding error
macroblock
compression ratio
error propagation effect
interframe prediction
rate-distortion curve
PSNR
simulation
twofold recompression
rate conversion
rate control
6 Mbit/s


An analytical model for a composite adaptive rectangular structure using the Heaviside function

Abstract: The objective of this article is to describe a mathematical model, based on the Heaviside function and on the delta -Dirac distribution, for a composite adaptive rectangular structure with embedded and/or bonded piezoelectric actuators and sensors. In the adopted structure model, the laminae are made up a configuration of rectangular nonpiezoelectric and piezoelectric patches. The laminae do not all have the same area nor do they present the same configuration, such that there are points where there is no material. The equations of motion and the boundary conditions, which describe the electromechanical coupling, are based on the Mindlin displacement field, on the linear theory of piezoelectricity, and on the Hamilton principle


Active vibration control of piezolaminated smart beams

Abstract: This paper deals with the active vibration control of beam like structures with distributed piezoelectric sensor and actuator layers bonded on top and bottom surfaces of the beam. A finite element model based on Euler-Bernoulli beam theory has been developed. The contribution of the piezoelectric sensor and actuator layers on the mass and stiffness of the beam is considered. Three types of classical control strategies, namely direct proportional feedback, constant-gain negative velocity feedback and Lyapunov feedback and an optimal control strategy, linear quadratic regulator (LQR) scheme are applied to study their control effectiveness. Also, the control performance with different types of loading, such as impulse loading, step loading, harmonic and random loading is studied

distributed piezoelectric actuator layers


A novel approach for the detection of pathlines in X-ray angiograms: the wavefront propagation algorithm

Abstract: Presents a new pathline approach, based on the wavefront propagation principle, and developed in order to reduce the variability in the outcomes of the quantitative coronary artery analysis. This novel approach, called wavepath, reduces the influence of the user-defined start- and endpoints of the vessel segment and is therefore more robust and improves the reproducibility of the lesion quantification substantially. The validation study shows that the wavepath method is totally constant in the middle part of the pathline, even when using the method for constructing a bifurcation or sidebranch pathline. Furthermore, the number of corrections needed to guide the wavepath through the correct vessel is decreased from an average of 0.44 corrections per pathline to an average of 0.12 per pathline. Therefore, it can be concluded that the wavepath algorithm improves the overall analysis substantially

wavefront propagation principle
quantitative coronary artery analysis
user-defined startpoints
user-defined endpoints
vessel segment
lesion quantification
wavepath method
bifurcation
sidebranch pathline
corrections
correct vessel
wavefront propagation algorithm
X-ray angiograms


Optimal bandwidth utilization of all-optical ring with a converter of degree 4

Abstract: In many models of all-optical routing, a set of communication paths in a network is given, and a wavelength is to be assigned to each path so that paths sharing an edge receive different wavelengths. The goal is to assign as few wavelengths as possible, in order to use the optical bandwidth efficiently. If a node of a network contains a wavelength converter, any path that passes through this node may change its wavelength. Having converters at some of the nodes can reduce the number of wavelengths required for routing. This paper presents a wavelength converter with degree 4 and gives a routing algorithm which shows that any routing with load L can be realized with L wavelengths when a node of an all-optical ring hosts such a wavelength converter. It is also proved that 4 is the minimum degree of the converter to reach the full utilization of the available wavelengths if only one node of an all-optical ring hosts a converter

all-optical routing
communication paths
all-optical network
wavelength assignment
wavelength translation
wavelength converter
all-optical ring


Friedberg numberings of families of n-computably enumerable sets

Abstract: We establish a number of results on numberings, in particular, on Friedberg numberings, of families of d.c.e. sets. First, it is proved that there exists a Friedberg numbering of the family of all d.c.e. sets. We also show that this result, patterned on Friedberg's famous theorem for the family of all c.e. sets, holds for the family of all n-c.e. sets for any n > 2. Second, it is stated that there exists an infinite family of d.c.e. sets without a Friedberg numbering. Third, it is shown that there exists an infinite family of c.e. sets (treated as a family of d.c.e. sets) with a numbering which is unique up to equivalence. Fourth, it is proved that there exists a family of d.c.e. sets with a least numbering (under reducibility) which is Friedberg but is not the only numbering (modulo reducibility)


Taking it to the max [ventilation systems]

Abstract: Raising the volumetric air supply rate is one way of increasing the cooling capacity of displacement ventilation systems. David Butler and Michael Swainson explore how different types of diffusers can help make this work

volumetric air supply rate
cooling capacity
displacement ventilation systems
diffusers


Sigma -admissible families over linear orders

Abstract: Admissible sets of the form HYP(M), where M is a recursively saturated system, are treated. We provide descriptions of subsets M, which are Sigma /sub */-sets in HYP(M), and of families of subsets M, which form Sigma -regular families in HYP(M), in terms of the concept of being fundamental couched in the article. Fundamental subsets and families are characterized for models of dense linear orderings

Sigma -admissible families
linear orders
HYP(M)
recursively saturated system
fundamental subsets
dense linear orderings


Self-organized critical traffic in parallel computer networks

Abstract: In a recent paper, we analysed the dynamics of traffic flow in a simple, square lattice architecture. It was shown that a phase transition takes place between a free and a congested phase. The transition point was shown to exhibit optimal information transfer and wide fluctuations in time, with scale-free properties. In this paper, we further extend our analysis by considering a generalization of the previous model in which the rate of packet emission is regulated by the local congestion perceived by each node. As a result of the feedback between traffic congestion and packet release, the system is poised at criticality. Many well-known statistical features displayed by Internet traffic are recovered from our model in a natural way

self-organized critical traffic
traffic flow dynamics
phase transition
free phase
congested phase
transition point
optimal information transfer
wide fluctuations
scale-free properties
generalization
packet emission
packet release
statistical features
Internet traffic
square lattice architecture
parallel computer networks


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