role-based access control for publish/subscribe middleware architectures Research into publish/subscribe messaging has so far done little to propose architectures for the support of access control, yet this will be an increasingly critical requirement as systems move to Internet-scale. This paper discusses the general requirements of publish/subscribe systems with access control. We then present our specific integration of OASIS role-based access control into the Hermes publish/subscribe middleware platform. Our system supports many advanced features, such as the ability to work within a network where nodes are attributed different levels of trust, and employs a variety of access restriction methods which balance expressiveness with the content-based routing optimisations available. We illustrate our achievements by discussing an application scenario in which our system will be of particular use.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

publish/subscribe
role-based access control
broker trust


Region-rejection based heuristics for the capacitated multi-source Weber problem A new type of constructive and adaptive heuristics is put forward to generate initial solutions for the capacitated multi-source Weber problem. This technique is based on guiding the search by constructing restricted regions that forbid new locations to be sited too close to the previously found locations. In this work, a restricted region is represented by a circle whose radius is initially set to a fixed value, based on the sparsity of the customers and the number of facilities, and then a scheme that dynamically adjusts the radius at each facility is proposed. A discretisation technique that divides a continuous space into a discrete number of cells while embedding the use of restricted regions within the search is also presented. The experiments show that the proposed region-rejection methods, though simple and easy to understand, provide encouraging results with regard to both solution quality and computational effort. Some future research avenues are also briefly highlighted.

O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

continuous location
capacitated location


Prediction of iron losses of wound core distribution transformers based on artificial neural networks This paper presents an artificial neural network (ANN) approach to predicting and classifying distribution transformer specific iron losses, i.e., losses per weight unit. The ANN is trained to learn the relationship of several parameters affecting iron losses. For this reason, the ANN learning and testing sets are formed using actual industrial measurements, obtained from previous completed transformer constructions. Data comprise grain oriented steel electrical characteristics, cores constructional parameters, quality control measurements of cores production line and transformers assembly line measurements. It is shown that an average absolute error of 2.32% has been achieved in the prediction of individual core specific iron losses and an error of 2.2% in case of transformer specific losses. This is compared with average errors of 5.7% and 4.0% in prediction of specific iron losses of individual core and transformer, respectively, obtained by the current practice applying the typical loss curve to the same data.

O O O O O B I I I O O B I I O O O O O O O O O O O O O O B I I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

wound core distribution transformers
individual core specific iron losses
transformer specific iron losses
artificial neural networks

specific iron losses prediction and classification


On the tightness of the alternating-cycle lower bound for sorting by reversals We give a theoretical answer to a natural question arising from a few years of computational experiments on the problem of sorting a permutation by the minimum number of reversals, which has relevant applications in computational molecular biology. The experiments carried out on the problem showed that the so-called alternating-cycle lower bound is equal to the optimal solution value in almost all cases, and this is the main reason why the state-of-the-art algorithms for the problem are quite effective in practice. Since worst-case analysis cannot give an adequate justification for this observation, we focus our attention on estimating the probability that, for a random permutation of n elements, the above lower bound is not tight. We show that this probability is low even for small n, and asymptotically Theta(1/n(5)), i.e., O(1/n(5)) and Omega(1/n(5)). This gives a satisfactory explanation to empirical observations and shows that the problem of sorting by reversals and its alternating-cycle relaxation are essentially the same problem, with the exception of a small fraction of "pathological" instances, justifying the use of algorithms which are heavily based on this relaxation. From our analysis we obtain convenient sufficient conditions to test if the alternating-cycle lower bound is tight for a given instance. We also consider the case of signed permutations, for which the analysis is much simpler, and show that the probability that the alternating-cycle lower bound is not tight for a random signed permutation of m elements is asymptotically Theta(1/m(2)).

O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O

tightness of lower bounds
alternating-cycle relaxation
counting


safe memory reclamation for dynamic lock-free objects using atomic reads and writes A major obstacle to the wide use of lock-free data structures, despite their many performance and reliability advantages, is the absence of a practical lock-free method for reclaiming the memory of dynamic nodes removed from dynamic lock-free objects for arbitrary reuse.The only prior lock-free memory reclamation method depends on the DCAS atomic primitive, which is not supported on any current processor architecture. Other memory management methods are blocking, require special operating system support, or do not allow arbitrary memory reuse.This paper presents the first lock-free memory management method for dynamic lock-free objects that allows arbitrary memory reuse, and does not require special operating system or hardware support. It guarantees an upper bound on the number of removed nodes not yet freed at any time, regardless of thread failures and delays. Furthermore, it is wait-free, it is only logarithmically contention-sensitive, and it uses only atomic reads and writes for its operations. In addition, it can be used to prevent the ABA problem for pointers to dynamic nodes in most algorithms, without requiring extra space per pointer or per node.

O O O O B O O O O O O O O O O O O O B O O B I O O O B O B O O O O O O B O B O O O O O B O O O B O O O O O O O O O O B O O O O O O O O O O O O O B B O O B O O O O O B I B O O O O O O O B O O O O O B B O B O O O O O O B O O O O O B I O B B O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O B O O O O O O O B O O O O O

reuse
use
performance
data structures
paper
pointers
practical
management
processor
thread
method
space
reliability
dynamic
architecture
operating system
support
hardware

sensitive delay object timing failure lock-free contention atom wait-free operability memorialized algorithm


NCBI disease corpus: A resource for disease name recognition and concept normalization NCBI disease corpus is built as a gold-standard resource for disease recognition. 793 PubMed abstracts are annotated with disease mentions and concepts (MeSH/OMIM). 14 Annotators produced high consistency level and inter-annotator agreement. Normalization benchmark results demonstrate the utility of the corpus. The corpus is publicly available to the community.

O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

named entity recognition
disease name normalization
corpus annotation
disease name corpus


testing pervasive software in the presence of context inconsistency resolution services Pervasive computing software adapts its behavior according to the changing contexts. Nevertheless, contexts are often noisy. Context inconsistency resolution provides a cleaner pervasive computing environment to context-aware applications. A faulty context-aware application may, however, mistakenly mix up inconsistent contexts and resolved ones, causing incorrect results. This paper studies how such faulty context-aware applications may be affected by these services. We model how programs should handle contexts that are continually checked and resolved by context inconsistency resolution, develop novel sets of data flow equations to analyze the potential impacts, and thus formulate a new family of test adequacy criteria for testing these applications. Experimentation shows that our approach is promising.

O O O O O O O B I I O B I O O O O O O O O O O O O O O B I I O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O

context inconsistency resolution
pervasive computing
test adequacy


A theoretical study of structural and electronic properties of pentacene/Al(100) interface The first principle calculations within the framework of density functional theory have been performed for the pentacene molecule deposited on the aluminum Al(100) substrate to study the structural and electronic properties of the pentacene/Al(100) interface. The most stable configuration was found at bridge site with 45 rotation of the pentacene molecule on Al(100) surface with a vertical distance of 3.4 within LDA and 3.8 within GGA functionals. The calculated adsorption energy reveals that the adsorption of pentacene molecule on Al(100) surface is physisorption. For the stable adsorption geometry the electronic properties such as density of states (DOS), partial density of states (PDOS), Mulliken population analysis and Schottky barrier height are studied. The analysis of atomic charge, DOS and PDOS show that the charge is transferred from the Al(100) surface to pentacene molecule, and the transferred charge is about ?0.05 electrons. For the adsorbed system, the calculated Schottky barrier height for hole and electron transport is 0.27 and 1.55eV, respectively.

O O O O O O O O O O O O O O O O O O O B I I O O O O O B O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O

pentacene
aluminum
density functional theory
physisorption


Wavelet Frame Accelerated Reduced Support Vector Machines In this paper, a novel method for reducing the runtime complexity of a support vector machine classifier is presented. The new training algorithm is fast and simple. This is achieved by an over-complete wavelet transform that finds the optimal approximation of the support vectors. The presented derivation shows that the wavelet theory provides an upper bound on the distance between the decision function of the support vector machine and our classifier. The obtained classifier is fast, since a Haar wavelet approximation of the support vectors is used, enabling efficient integral image-based kernel evaluations. This provides a set of cascaded classifiers of increasing complexity for an early rejection of vectors easy to discriminate. This excellent runtime performance is achieved by using a hierarchical evaluation over the number of incorporated and additional over the approximation accuracy of the reduced set vectors. Here, this algorithm is applied to the problem of face detection, but it can also be used for other image-based classifications. The algorithm presented, provides a 530-fold speedup over the support vector machine, enabling face detection at more than 25 fps on a standard PC.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O

cascaded evaluation
coarse-to-fine classifier
machine learning
over-complete wavelet transform (ocwt)
reduced support vector machine (rvm)


Measurement and evidence of computer-based task switching and multitasking by 'Net Generation' students Logs of on-campus computer and Internet usage were used to conduct a study of computer-based task switching and multitasking by undergraduate medical students. A detailed analysis of over 6000 individual sessions revealed that while a majority of students engaged in both task switching and multitasking behaviours, they did so less frequently than 'Net Generation' rhetoric implies. The incidence and intensity of task switching and multitasking among students ranged from low to very high but infrequent and low-level multitaskers easily outnumbered inveterate multitaskers. Male and international students were significantly more likely to task switch and multitask than their female and local counterparts. Students who entered University directly from secondary school were significantly more likely to multitask than graduate students, as were first year compared to second year students, suggesting that post-secondary experiences may temper students' propensity or inclination to multitask. (c) 2010 Elsevier Ltd. All rights reserved.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

teaching/learning strategies
navigation
media in education


Pseudo-BCK algebras and PD-posets The notion of pseudo-BCK algebras was introduced by Georgescu and Iorgulescu Proceedings of DMTCS'01: Combinatorics, Computability and Logic, Springer, London, pp 97-114, 2001. It is so general that fleas, pseudo-hoops, psMTL, psBL, pseudo-MV et al., and so hoops, MTL, BL, MV et al. can be seen its extensions. In this paper, we extend the ideal and congruence theory to pseudo-BCK algebras, and investigate the connections between pseudo-BCK algebras and PD(GPD)-posets.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O B O O O O O O O O O O O O O

pseudo-bck algebra
normal ideal
prime ideal
pd-poset


linearising nonlinear recursions in polynomial time The replacement of nonlinear recursions with equivalent linear recursions is a potentially useful query optimization strategy, since it permits the use of efficient algorithms for the evaluation of linear logic programs. We show that a member of a certain class of bilinear recursions is linearizable in a strong sense if and only if a specific partial proof tree derived from this recursion is contained in a bounded number of partial proof trees generated by the recursion. Further, while each such test of containment between proof trees involves an exponential number of conjunctive-query containment tests, we present syntactic conditions on the recursion that are necessary and sufficient for the containment and verifiable in polynomial time.

O O O O B O O O O O O O O O O O O O O B I O O O O O B O O O O O B O B I O O O O O O O O O B O O O O O O O O O O O O O O O O O B O O O B O O O O O O O O O B O O O B O O O O B O O O O B O O O O O O O O O O O O O O B O O O O O O O O O O O B O

tree
use
recursion
polynomial
test
linear logic
trees
query optimization
evaluation
class

program
strategies
efficiency
conjunctive queries
linearizability
timing
algorithm
container


a type system for well-founded recursion In the interest of designing a recursive module extension to ML that is as simple and general as possible, we propose a novel type system for general recursion over effectful expressions. The presence of effects seems to necessitate a backpatching semantics for recursion similar to that of Scheme. Our type system ensures statically that recursion is well-founded---that the body of a recursive expression will evaluate without attempting to access the undefined recursive variable---which avoids some unnecessary run-time costs associated with backpatching. To ensure well-founded recursion in the presence of multiple recursive variables and separate compilation, we track the usage of individual recursive variables, represented statically by "names". So that our type system may eventually be integrated smoothly into ML's, reasoning involving names is only required inside code that uses our recursive construct and need not infect existing ML code, although instrumentation of some existing code can help to improve the precision of our type system.

O B I O O B O O O O O O O B O O B O O O O O B O O O O O O B I O B B O O O O B O O O O O O O O O B O O O O B O B I O O O B O O O O O O O O O O O O O B O O O O O O O O O O O O O O O B O O B O O O O O B I O O O O O O O O O O O O O O O B I O O O O O O O B O O O O O O B O O O O O O O O O O B B O O O O O B O B O O O O O O B I

help
ml
presence
separate compilation
general
access
type system
reasoning
recursion
code
module
scheme

precise
association
express
extensibility
effect systems
timing
instrument
recursive modules
evaluation
variability
semantic
yype systems
tracking
effect
integrability


In vivo validation of a novel method for regional myocardial wall motion analysis based on echocardiographic tissue tracking The objective of this study was to validate a recently developed tissue tracking (TT) method for cardiac motion, by comparing it with precise invasive measurements of motion and to prove its capability to reflect moderate hemodynamic changes induced by asynchronous activation. In four open-chest sheep, sono-crystals measured the left ventricle(LV) equators diameters simultaneously with 2D ultrasound acquisition. The LV was paced either from the posterior or from the lateral wall, just prior to the normal LV activation. Global functional indices were calculated based on the regional motions extracted by the TT method. The correlation coefficient between the shortening of the diameters and the global circumferential strain (GCS) was 0.990.004. The peak GCS differentiated between the pacing modes (paired t test, P<0.05). The GCS, a measurement closely based on the TT method, followed the precise sono-crystals measurements and reflected moderate hemodynamic changes, thus providing a substantial proof of the TT methods accuracy and clinical value.

O O O O O O O O O O O O O O O O B I O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

echocardiography
strain imaging
cardiac functional assessment


Some further results on weighted sharing three values and Broschs theorem Using the notion of weighted sharing of values we prove two uniqueness theorems which improve the results proved by T.C. Alzahary [T.C. Alzahary, Weighted sharing three values and Broschs theorem. J. Math. Anal. Appl. 323 (2006) 825; T.C. Alzahary, On a result of Ueda concerning unicity of meromorphic functions. Kodai. Math. J. 30 (2007) 140146], under a weaker hypothesis.

O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O


Scheduling of Water Distribution System Rehabilitation Using Structured Messy Genetic Algorithms A methodology is presented for the optimal design and scheduling of investment for the rehabilitation of water distribution networks. Based on the evolutionary programming technique known as Structured Messy Genetic Algorithms, the methodology utilizes a multi-objective formulation which improves the evolutionary process and provides non-dominated optimal solutions over a range of costs and benefits. The model is applied to an example-a small artificial network of fifteen pipes. The effects on the optimal solutions of varying parameters such as interest rate and inflation rate are also investigated.

B O B I O B O O O B I O O O O O O O O O B O O O O B O B I B O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

water distribution
genetic algorithms
scheduling
rehabilitation
networks


Characterization of the PAC1 Variants Expressed in the Mouse Heart Pituitary adenylate cyclase-activating polypeptide (PACAP), a pleiotropic neuropeptide, exerts a variety of physiological functions through three types of G proteincoupled receptors, PAC1, VPAC1, and VAPC2. Characterization of the molecular forms of PAC1 in mouse heart revealed the presence of four types of variant receptors harboring the N or S variant in the first extracellular domain (EC1 domain) with or without the HOP1 insert in the third intracellular cytoplasmic loop (IC3 loop). Then, we assessed the binding affinity and ability to stimulate adenylyl cyclase of the PCA1 variant-expressing cells for PACAP. Adenylyl cyclase activation by PACAP was markedly influenced with the variant in the EC1 domain as well as that in the IC3 loop, in spite of a little difference in their binding properties. These data suggest that the combination of EC1 domain variants and IC3 loop variants might account for the diversity of intracellular signaling, which might contribute to multiple functions of PACAP including a role in the cardiovascular system

O O O B O O O O O O O O O O B O O O O O O O O O O O O O O O O B O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O


ANNSyS: an Analog Neural Network Synthesis System A synthesis system based on a circuit simulator and a silicon assembler for analog neural networks to be implemented in MOS technology is presented. The system approximates on-chip training of the neural network under consideration and provides the best starting point for `chip-in-the-loop training'. Behaviour of the analog neural network circuitry is modeled according to its SPICE simulations and those models are used in the initial training of the analog neural networks prior to the fine tuning stage. In this stage, the simulator has been combined with Madaline Rule III for approximating on chip training by software, thus minimizing the effects of circuit nonidealities on neural networks. The circuit simulator partitions the circuit into decoupled blocks which can be simulated separately, with the output of one block being the input for the next one. Finally, the silicon assembler generates the layout for the neural network by reading analog standard cells from a library. The system's performance has been demonstrated by several examples.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

neural network implementations
multilayer perceptrons
circuit simulation
cmos neural networks
neural network training
macromodeling


simulation data structures using simula 67 This paper describes the approach to the teaching of simulation at the University of Montreal. The language used is the present standard of SIMULA, sometimes referred to as SIMULA 67; however, the modelling approach is inspired from GPSS. This combination of an old and a new language has proved very fruitful. Little has so far been published on the new standard for SIMULA and it is hoped that the examples in this paper may serve as a painless introduction to simulation programming in this language.

B B I O O O O B O O O O O B O B O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O B O O B O O O O O O O B O O O B

teaching
examples
paper
simulation
language
data structures

standardization program model combinational


SYMBMAT:

Symbolic

computation

of

quantum

transition

matrix

elements

We

have

developed

a

set

of

Mathematica

notebooks

to

compute

symbolically

quantum

transition

matrices

relevant

for

atomic

ionization

processes.

The

utilization

of

a

symbolic

language

allows

us

to

obtain

analytical

expressions

for

the

transition

matrix

elements

required

in

charged-particle

and

laser

induced

ionization

of

atoms.

Additionally,

by

using

a

few

simple

commands,

it

is

possible

to

export

these

symbolic

expressions

to

standard

programming

languages,

such

as

Fortran

or

C,

for

the

subsequent

computation

of

differential

cross

sections

or

other

observables.

One

of

the

main

drawbacks

in

the

calculation

of

transition

matrices

is

the

tedious

algebraic

work

required

when

initial

states

other

than

the

simple

hydrogenic

is

state

need

to

be

considered.

Using

these

notebooks

the

work

is

dramatically

reduced

and

it

is

possible

to

generate

exact

expressions

for

a

large

set

of

bound

states.

We

present

explicit

examples

of

atomic

collisions

(in

First

Born

Approximation

and

Distorted

Wave

Theory)

and

laser-matter

interactions

(within

the

Dipole

and

Strong

Field

Approximations

and

different

gauges)

using

both

hydrogenic

wavefunctions

and

Slater-Type

Orbitals

with

arbitrary

nlm

quantum

numbers

as

initial

states.

Program

summary

Program

title:

SymbMat

Catalogue

identifier:

Program

summary

URL:

Program

obtainable

from:

CPC

Program

Library,

Queen's

University,

Belfast,

N.

Ireland

Licensing

provisions:

Standard

CPC

license,

No.

of

lines

in

distributed

program,

including

test

data,

etc.:

No.

of

bytes

in

distributed

program,

including

test

data,

etc.:

Distribution

format:

tar.gz

Programming

language:

Mathematica

Computer:

Single

machines

using

Linux

or

Windows

(with

cores

with

any

clock

speed,

cache

memory

and

bits

in

a

word)

Operating

system:

Any

OS

that

supports

Mathematica.

The

notebooks

have

been

tested

under

Windows

and

Linux

and

with

versions

and

Classification:

Nature

of

problem:

The

notebooks

generate

analytical

expressions

for

quantum

transition

matrix

elements

required

in

diverse

atomic

processes:

ionization

by

ion,

electron,

or

photon

impact

and

ionization

within

the

framework

of

strong

field

physics.

In

charged-particle

collisions

approaches

based

on

perturbation

theory

enjoy

widespread

utilization.

Accordingly,

we

have

chosen

the

First

Born

Approximation

and

Distorted

Wave

theories

as

examples.

In

light-matter

interactions,

the

main

ingredient

for

many

types

of

calculations

is

the

dipole

transition

matrix

in

its

different

formulations,

i.e.

length,

velocity,

and

acceleration

gauges.

In

all

these

cases

the

transitions

of

interest

occur

between

a

bound

state

and

a

continuum

state

which

can

be

described

in

different

ways.

With

the

notebooks

developed

in

the

present

work

it

is

possible

to

calculate

transition

matrix

elements

analytically

for

any

set

of

quantum

numbers

nlm

of

initial

hydrogenic

states

or

Slater-Type

Orbitals

and

for

plane

waves

or

Coulomb

waves

as

final

continuum

states.

Solution

method:

The

notebooks

employ

symbolic

computation

to

generate

analytical

expressions

for

transition

matrix

elements

used

in

both

collision

and

light-matter

interaction

physics.

Additional

comments:

The

set

consists

of

the

following

notebooks:

This

notebook

computes

analytical

expressions

for

the

transition

matrix

of

collision-induced

ionization

in

the

First

Born

Approximation

(FBA).

The

transitions

considered

are

from

a

bound

hydrogenic

state

with

arbitrary

quantum

numbers

nlm

to

a

continuum

state

represented

by

a

plane

wave

(PW)

or

a

Coulomb

wave

(CW).

This

notebook

computes

analytical

expressions

for

the

transition

matrix

of

collision-induced

ionization

in

Distorted

Wave

(DW)

theories.

The

transitions

considered

are

from

a

(distorted)

bound

hydrogenic

state

with

arbitrary

quantum

numbers

nlm

to

a

distorted-wave

continuum

state.

The

computations

are

based

on

scalar

and

vectorial

integrals

(see

the

text

for

details).

This

notebook

computes

analytical

expressions

for

the

dipole

transition

matrix

in

length

gauge.

The

transitions

considered

are

from

a

bound

hydrogenic

state

with

arbitrary

quantum

numbers

nlm

to

a

continuum

state

represented

by

a

PW

(the

Strong

Field

Approximation

(SFA))

or

a

CW

(the

Coulomb-Volkov

Approximation

(CVA)).

This

notebook

computes

analytical

expressions

for

the

dipole

transition

matrix

in

velocity

gauge.

The

transitions

considered

are

from

a

bound

hydrogenic

state

with

arbitrary

quantum

numbers

nlm

to

a

continuum

state

represented

by

a

PW

(the

SFA)

or

a

CW

(the

CVA).

This

notebook

computes

analytical

expressions

for

the

dipole

transition

matrix

in

acceleration

gauge.

The

transitions

considered

are

from

a

bound

hydrogenic

state

with

arbitrary

quantum

numbers

nlm

to

a

continuum

state

represented

by

a

PW

(the

SFA).

For

the

case

of

the

CVA

we

only

include

the

transition

from

the

is

state

to

a

continuum

state

represented

by

a

CW.

This

notebook

computes

analytical

expressions

for

the

transition

matrix

of

collision-induced

ionization

in

the

FBA.

The

transitions

considered

are

from

a

Slater-Type

Orbital

(STO)

with

arbitrary

quantum

numbers

nlm

to

a

continuum

state

represented

by

a

PW

or

a

CW.

This

notebook

computes

analytical

expressions

for

the

transition

matrix

of

collision-induced

ionization

in

DW

theories.

The

transitions

considered

are

from

a

(distorted)

STO

with

arbitrary

quantum

numbers

nlm

to

a

distorted-wave

continuum

state.

The

computations

are

based

on

scalar

and

vectorial

integrals

(see

the

text

for

details).

This

notebook

computes

analytical

expressions

for

the

dipole

transition

matrix

in

length

gauge.

The

transitions

considered

are

from

an

STO

with

arbitrary

quantum

numbers

nlm

to

a

continuum

state

represented

by

a

PW

(the

SFA)

or

a

CW

(the

CVA).

This

notebook

computes

analytical

expressions

for

the

dipole

transition

matrix

in

velocity

gauge.

The

transitions

considered

are

from

an

STO

with

arbitrary

quantum

numbers

nlm

to

a

continuum

state

represented

by

a

PW

(the

SFA)

or

a

CW

(the

CVA).

This

notebook

computes

analytical

expressions

for

the

dipole

transition

matrix

in

acceleration

gauge.

The

transitions

considered

are

from

an

STO

with

arbitrary

quantum

numbers

nlm

to

a

continuum

state

represented

by

a

PW

(the

SFA).

The

symbolic

expressions

obtained

within

each

notebook

can

be

exported

to

standard

programming

languages

such

as

Fortran

or

C

using

the

Format.m

package

(see

the

text

and

Ref.

Sofroniou

for

details).

Running

time:

Computational

times

vary

according

to

the

transition

matrix

selected

and

quantum

numbers

nlm

of

the

initial

state

used.

The

typical

running

time

is

several

minutes,

but

it

will

take

longer

for

large

values

of

nlm.

(C)

Elsevier

B.V.

All

rights

reserved.

O B I O O O O O O O O O O O B O O O O B I I O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

symbolic computation
quantum transition matrices
atomic ionization processes
mathematica


Mobility-aware timeout medium access control protocol for wireless sensor networks Wireless sensor networks (WSNs), has been under development for a while by the academia and industry. Due to limited computational power, a typical sensor node may experience operational challenges. Moreover, mobility has become an important feature since emergency and healthcare related applications are evolving in WSNs. Consideration of mobile nodes in WSNs introduce new challenges for the designers. In this paper, an enhanced version of T-MAC protocol (a well-known medium access control protocol in WSNs) known as MT-MAC is proposed. Using the capturing fluctuation in RSSI and LQI values of the received SYNC packets, MT-MAC solves high packet drop ratio in T-MAC. By detecting the mobility, a mobile node softly handover to a new virtual cluster without losing connection with other nodes. The performance of the proposed solution is then compared with T-MAC, S-MAC as well as other well-known mobility-aware MAC (MS-MAC) protocol. The simulation results show that the proposed protocol significantly increases the throughput and packet delivery ratio of T-MAC in exchange for a small increase in power consumption. Compared to MS-MAC protocol, the proposed approach can reduce power consumption by 2065%, and achieve slightly higher packet delivery ratio.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O B I O O O O O O O O O

wireless sensor network
mac protocols
energy efficiency


Reconstruction of missing features by means of multivariate Laplace distribution (MLD) for noise robust speech recognition Speech recognition accuracy degrades in presence of additive noise, especially when recognizer's training data is clean. Several methods have been proposed to compensate effects of noise on recognition accuracy. Among these methods, Missing Feature Techniques (MFT) have shown promising results. Two different MF approaches have been introduced in literature: "Model-Based" and "Feature-Based" approaches. In the first category, the state distribution calculations should be changed and also some modifications are required to cope with filter bank features. But, in the second category, compensated representations of corrupted signals are reconstructed prior to recognition, and conventional recognizers, using MFCC features, are then used. In "Feature-Based" MFT, spectral vectors of speech signal frames are conventionally modeled by a Gaussian distribution (GD) and according to estimated parameters of the models, missed parts of speech representation are reconstructed. In this paper, we consider some researches that suggest multivariate Laplace distribution (MLD) to be a proper distribution for modeling speech signal. Here, we examine this idea in modeling log spectral representation of speech frames, and show that MLD acts better than Gaussian distribution. Moreover, We apply the Maximum Likelihood (ML) estimation of missing elements conditioned on observed values with respect to MLD and prove that the estimation equations are simple and tractable and by using this estimation in reconstruction of missing features, we gain better phoneme recognition accuracy against using "GD", in noisy conditions. In SNR values blew 10 dB in the cases of all of the noises, MLD improves the recognition accuracy more than 4% in most of the cases. (C) 2010 Elsevier Ltd. All rights reserved.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O


Modelling retrieval models in a probabilistic relational algebra with a new operator: the relational Bayes This paper presents a probabilistic relational modelling (implementation) of the major probabilistic retrieval models. Such a high-level implementation is useful since it supports the ranking of any object, it allows for the reasoning across structured and unstructured data, and it gives the software (knowledge) engineer control over ranking and thus supports customisation. The contributions of this paper include the specification of probabilistic SQL (PSQL) and probabilistic relational algebra (PRA), a new relational operator for probability estimation (the relational Bayes), the probabilistic relational modelling of retrieval models, a comparison of modelling retrieval with traditional SQL versus modelling retrieval with PSQL, and a comparison of the performance of probability estimation with traditional SQL versus PSQL. The main findings are that the PSQL/PRA paradigm allows for the description of advanced retrieval models, is suitable for solving large-scale retrieval tasks, and outperforms traditional SQL in terms of abstraction and performance regarding probability estimation.

O B I O O O O O O O O O O O O O O O O B I I O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O

probabilistic relational modelling
retrieval models

probabilistic databases
db plus ir integration


Why the cosmos has to be stochastic It will be shown that the hypothesis of universal determinism fits Poorly with the empirical realities of human life, and that no age of science (after 500BC) has embraced it After tracing the history of universal determinism, we shall show how in the mid-nineteenth century arose the idea of a stochastic cosmos, in which the laws of nature are probabilistic, and in which "possibilities", in accord with natural law are in excess of actualities.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O


noc-aware cache design for multithreaded execution on tiled chip multiprocessors In chip multiprocessors (CMPs), data access latency depends on the memory hierarchy organization, the on-chip interconnect (NoC), and the running workload. Reducing data access latency is vital to achieving performance improvements and scalability of threaded applications. Multithreaded applications generally exhibit sharing of data among the program threads, which generates coherence and data traffic on the NoC. Many NoC designs exploit communication locality to reduce communication latency by configuring special fast paths on which communication is faster than the rest of the NoC. Communication patterns are directly affected by the cache organization. However, many cache organizations are designed in isolation of the underlying NoC or assume a simple NoC design, thus possibly missing optimization opportunities. In this work, we present a NoC-aware cache design that creates a symbiotic relationship between the NoC and cache to reduce data access latency, improve utilization of cache capacity, and improve overall system performance. Specifically, considering a NoC designed to exploit communication locality, we design a Unique Private caching scheme that promotes locality in communication patterns. In turn, the NoC exploits this locality to allow fast access to remote data, thus reducing the need for data replication and allowing better utilization of cache capacity. The Unique Private cache stores the data mostly used by a processor core in its locally accessible cache bank, while leveraging dedicated high speed circuits in the interconnect to provide remote cores with fast access to shared data. Simulations of a suite of scientific and commercial workloads show that our proposed design achieves a speedup of 14\% and 16\% on a 16-core and a 64-core CMP, respectively, over the state-of-the-art NoC-Cache co-designed system which also exploits communication locality in multithreaded applications.

O B O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O B O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O B O O O B O O O O O O O O B O O O O B O O O O O O O O O O O O O B O O O O O O O O B O B O O O O O O O O B O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O B O O O O B O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O


a comparison of tcp performance over three routing protocols for mobile ad hoc networks We examine the performance of the TCP protocol for bulk-data transfers in mobile ad hoc networks (MANETs). We vary the number of TCP connections and compare the performances of three recently proposed on-demand (AODV and DSR) and adaptive proactive (ADV) routing algorithms. It has been shown in the literature that the congestion control mechanism of TCP reacts adversely to packet losses due to temporarily broken routes in wireless networks. So, we prospose a simple heuristic, called fixed RTO, to distinguish between route loss and network congestion and thereby improve the performance of the routing algorithms. Using the ns -2 simulator, we evaluate the performances of the three routing algorithms with the standard TCP Reno protocol and Reno with fixed RTO. Our results indicate that the proactive ADV algorithm performs well under a variety of conditions and that the fixed RTO technique improves the performances of the two on-demand algorithms significantly

O O O O B O O B O O B I I I O O O B O O O O O O O O B I I I O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O B I O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O B B O O O O B O O B O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O

network
wireless networks
performance
routing
algorithm
congestion control
mobile ad hoc networks
congestion

manet
adapt
simulation
standardization
data
heuristics
routing protocol
connection
packet-loss
comparisons
routing algorithm
evaluation


Preemptive stochastic online scheduling on two uniform machines This paper addresses a stochastic online scheduling problem in which a set of independent jobs are to be processed by two uniform machines whose speeds are 1 and s (s >= 1). Each job has a processing time, which is a random variable with an arbitrary distribution, and all the jobs are arriving overtime, which means that no information of the job is known in advance before its arrival. During the processing, jobs are allowed to be preempted and resumed later. The objective is to minimize the sum of expected weighted completion times. In this paper, the optimal policy, named SMPR, is designed for the single-machine preemptive stochastic scheduling problem where jobs have a common arriving time. Based on SMPR, the online approximative policy-UMPR. is devised for the preemptive stochastic online scheduling on two uniform machines. Then, UMPR is proved to have an approximation factor of 2. Furthermore, it is concluded that UMPR could not have a smaller approximation factor than 2, which means 2 is the approximation ratio of UMPR for the two-uniform-machine scheduling problem. (C) 2008 Elsevier B.V. All rights reserved.

B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B B I O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

uniform machine
online policy
analysis of algorithms


the system of checking students' knowledge with the use of wide area networks In the situation when computers, and primarily wide area computer networks, are easily accessible, it is possible to conduct examinations with no need for the examinee and the examiner to be in the same place at the same time. This paper suggests how to carry out this postulate.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

knowledge testing
distance testing
wide area network
questions database
html browser


Aging speech recognition with speaker adaptation techniques: Study on medium vocabulary continuous Bengali speech The article describes the speech recognition system development in Bengali language for aging population with various adaptation techniques. Variability in acoustic characteristics among different speakers degrades speech recognition accuracy. In general, perceptual as well as acoustical variations exists among speakers, but variations are more pronounced between young and aged population. Deviation in voice source features between two age groups, affect the speech recognition performance. Existing automatic speech recognition algorithms demands large amount of training data with all variability to develop a robust speech recognition system. However, speaker normalization and adaptation techniques attempts to reduce inter-speaker or intra-speaker acoustic variability without having large amount of training data. Here, conventional acoustic model adaptation method e.g. vocal tract length normalization, maximum likelihood linear regression and/or maximum a posteriori are combined in the current study to improve recognition accuracy. Moreover, maximum mutual information estimation technique has been implemented in this study.

B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

maximum likelihood linear transform (mllt)

maximum likelihood linear regression (mllr)

maximum mutual information estimation (mmie)


Understanding the cost of capital of logistics service providers: an empirical investigation of multiple contingency variables The article analyzes the influence of company-, industry- and market-related variables on the cost of capital of logistics service providers, as well as on their systematic risk. Financial information has become more and more important in strategic decision making (especially in the international context); in addition of being a measure of performance, the cost of capital is an important variable for logistics service providers in decisions about investing capital and developing the appropriate strategy. In total, financial data on over 700 logistics service providers for a period of 10years were analyzed applying multiple regression analysis. Our results show that the logistics service industry is rather nonvolatile from an investors viewpoint. Microeconomic variables significantly influence the cost of capital of logistics service providers, whereas systematic risk is influenced by macroeconomic variables. In both cases, significance is strongly dependent on the services offered and financial structure of the companies, although the headquarters location is irrelevant. Main implication of our study underlines the specific interdependencies of strategic decision making and cost of capital of logistics service providers. As recent research made only little efforts in linking the fields of business logistics and corporate finance, we follow a broad research approach to give a first comprehensive overview on this interdisciplinary topic.

O O B I I O B I I O O O O O O O O O O O O O O O O O O O O B I I O B I I O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O O B I I O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O B I I O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

cost of capital
systematic risk
logistics service providers

key financial figures
strategic decisions
value creation


Speech recognition on DSP: issues on computational efficiency and performance analysis This paper provides a thorough description of the implementation of automatic speech recognition (ASR) algorithms on a fixed-point digital signal processor (DSP). It is intended to serve as a useful self-contained reference for DSP engineers to follow when developing similar applications. The work is based on a detailed analysis of hidden Markov model (HMM) based ASR algorithms. The computationally critical steps are clearly identified, and for each of them, different ways of optimization for real-time computation are suggested and evaluated. The trade-off among computational efficiency, memory requirements and recognition performance is illustrated quantitatively via three example systems, one for the recognition of isolated Chinese words and the other two for the recognition of English and Chinese digit strings, respectively. The paper also discusses about other techniques that can be implemented to further improve the recognition performance in real-world applications.

O O O O O O O O O O O O O O O O O O O O O B I I O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

digital signal processor
automatic speech recognition
memory requirements

computational complexity
duration modeling


A New Variant of 3GPP-MAC With Provable Security and Higher Efficiency 3GPP-MAC, also called f9, is an integrity scheme adopted by Universal Mobile Telecommunication System as a standard for the 3rd generation wireless communications. In this paper, we investigate the feasibility of improving its efficiency, with the precondition that its security would not be compromised. As we show, the newly proposed f9(-) enjoys provable security under the solo P RP assumption; m ore importantly, f9(-) removes the last block-cipher invocation of f9, which means it needs less time and resources to compute MACs than f9, offering higher efficiency in practice. Furthermore, f9(-) keeps the main structure of f9 almost unchanged, making it easy to update f9 to f9(-) in reality.

O O O O O O B I O O B O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O


Momentum/continuity coupling with large non-isotropic momentum source terms Pressure-based methods such as the SIMPLE algorithm are frequently used to determine a Coupled solution between the component momentum equations and the continuity equation. This paper presents a colocated variable pressure correction algorithm for control volumes of polyhedral/polygonal cell topologies. The correction method is presented independent of spatial approximation. The presence of non-isotropic momentum source terms is included in the proposed algorithm to ensure its applicability to multi-physics applications such as gas and particulate flows. Two classic validation test cases are included along with a newly proposed test case specific to multiphase flows. The classic validation test cases demonstrate the application of the proposed algorithm on truly arbitrary polygonal/polyhedral cell meshes. A comparison between the current algorithm and commercially available software is made to demonstrate that the proposed algorithm is competitively efficient. The newly proposed test case demonstrates the benefits of the current algorithm when applied to a multiphase flow situation. The numerical results from this case show that the proposed algorithm is more robust than other methods previously proposed. Copyright (c) 2009 John Wiley & Sons, Ltd.

O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

polyhedral
incompressible
cfd
laminar
non-isotrophic source term


An extension of min/max flow framework In this paper, the min/max flow scheme for image restoration is revised. The novelty consists of the following three parts. The first is to analyze the reason of the speckle generation and then to modify the original scheme. The second is to point out that the continued application of this scheme cannot result in an adaptive stopping of the curvature flow. This is followed by modifications of the original scheme through the introduction of the Gradient Vector Flow (GVF) field and the zero-crossing detector, so as to control the smoothing effect. Our experimental results with image restoration show that the proposed schemes can reach a steady state solution while preserving the essential structures of objects. The third is to extend the min/max flow scheme to deal with the boundary leaking problem, which is indeed an intrinsic shortcoming of the familiar geodesic active contour model. The min/max flow framework provides us with an effective way to approximate the optimal solution. From an implementation point of view, this extended scheme makes the speed function simpler and more flexible. The experimental results of segmentation and region tracking show that the boundary leaking problem can be effectively suppressed.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O B I O O O O O

min/max flow framework
anisotropic diffusion
image segmentation


Clique packing approximation for analysis of teletraffic characteristics of dynamic channel assignment considering mobility This paper discusses the teletraffic characteristics of cellular systems using Dynamic Channel Assignment. In general. it is difficult to exactly and theoretically analyze the teletraffic characteristics of Dynamic Channel Assignment. Also, it is not easy to theoretically evaluate influence of mobility on the traffic characteristics. This paper proposes approximate techniques to analyze teletraffic characteristics of Dynamic Channel Assignment considering mobility. The proposed techniques are based on Clique Packing approximation.

B I O O O O B I O B I I O O O O O O B I O O O O B I I O O O O O O O O O O O B I O B I I O O O O O O O O O O O O O O O O O O O O O O B I O B I I O O O O O O O O B I O

dynamic channel assignment
clique packing
teletraffic characteristics


Analysis of power spectrum and 1/f type power law in a complex computer network model The computer network, as a complex nonlinear system, exhibits plenty of nonlinear complexities phenomena. More and more researchers have been attracted to these exciting dynamic behaviors, In general, computer simulation studies are widely used in the researches on network dynamics. Unfortunately, too simple and regular topologies are adopted in these network models. It inevitably results in the fact that some important complexities behaviors in a real computer network may not emerge in most of computer experimental studies. In this paper, the phase transition phenomena between the packer creation rate and the lifetime of packet, on basis of more realistic computer network models composed of the Transit-Stub topology and the proposed mechanism of packet traffic, are explored. To illustrate the fluctuation of packets more clearly, a power spectrum is made and the 1/f type power law is found. Finally, simulation results and some research emphases in the future are discussed. (C) 2001 Elsevier Science B.V. All rights reserved.

O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O


an information flow model of fault detection RELAY is a model of how a fault causes a failure on execution of some test datum. This process begins with introduction of an original state potential failure at a fault location and continues as the potential failure(s) transfers to output. Here we describe the second stage of this process, transfer of an incorrect intermediate state from a faulty statement to output. Transfer occurs along information flow chains, where each link in the chain involves data dependence transfer and/or control dependence transfer. RELAY models concurrent transfer along multiple information flow chains with transfer sets, which identify possible interaction between potential failures, and with transfer routes, which identify actual interactions. Transfer sets, transfer routes, and control dependence transfer are unique to the RELAY model. The model demonstrates that the process of potential failure transfer is extremely complex and full analysis of real programs may not be practical. Nonetheless, RELAY provides insight into testing and fault detection and suggests an approach to fault-based testing and analysis that may be warranted for critical systems software.

O B I B O B O O O O B O O O B O O B O O O O B O O B O O O O O O O O B O O B O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O B I O O O O O O O O B I O O B I O O O O O O O B I O O O O O O O B O O O O O O O O O O O O O O O O B I O O O O O O B O B O O O B O O B O O O O O O B O O O O O O B O O O O O O O B O O O O O O O O O B O O O O O O B B

interaction
information flow
software
systems
test
analysis
data dependence
process
fault
model
control dependence
practical
failure

program locatability fault-detection concurrency routing complexity critic linking


on-line behaviour classification and adaptation to human-robot interaction styles This paper presents a proof-of-concept of a robot that is adapting its behaviour on-line, during interactions with a human according to detected play styles. The study is part of the AuRoRa project which investigates how robots may be used to help children with autism overcome some of their impairments in social interactions. The paper motivates why adaptation is a very desirable feature of autonomous robots in human-robot interaction scenarios in general, and in autism therapy in particular. Two different play styles namely 'strong' and 'gentle', which refer to the user, are investigated experimentally. The model relies on Self-Organizing Maps, used as a classifier, and on Fast Fourier Transform to preprocess the sensor data. First experiments were carried out which discuss the performance of the model. Related work on adaptation in socially assistive and therapeutic work are surveyed. In future work, with typically developing and autistic children, the concrete choice of the robot's behaviours will be tailored towards the children's interests and abilities.

O B I O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

interaction styles
behaviour classification


Approximation algorithms for multicast routing in ad hoc wireless networks Energy efficient multicast problem is one of important issues in ad hoc networks. In this paper, we address the energy efficient multicast problem for discrete power levels in ad hoc wireless networks. The problem of our concern is: given n nodes deployed over 2-D plane and each node v has l(v) transmission power levels and a multicast request (s,D) (clearly, when D is Va-{s}, the multicast request is a broadcast request), how to find a multicast tree rooted at s and spanning all destinations in D such that the total energy cost of the multicast tree is minimized. We first prove that this problem is NP-hard and it is unlikely to have an approximation algorithm with performance ratio rho lnn(rho < 1). Then, we propose a general algorithm for the multicast/broadcast tree problem. And based on the general algorithm, we propose an approximation algorithm and a heuristics for multicast tree problem. Especially, we also propose an efficient heuristic for broadcast tree problem. Simulations ensure our algorithms are efficient.

O O O B I O O O O O B I O O O O O O O O B I I O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O B O O O O O O O O O O

approximation algorithm
heuristic
energy efficient
multicast routing
ad hoc networks


Quantum Monte Carlo methods in statistical mechanics This paper deals with the optimization of trial states for the computation of dominant eigenvalues of operators and very large matrices. In addition to preliminary results for the energy spectrum of van der Waals clusters, we review results of the application of this method to the computation of relaxation times of independent relaxation modes at the Ising critical point in two dimensions.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I I O O O O O O O O O O O O O O O O O O O O O O O O O O O

universal critical point amplitudes
correlation times
trial state optimization


a new palm vein matching method based on icp algorithm Palm vein as a new and promising biometric feature has drawn lots of research and industry attention. Palm vein owns many outstanding characteristics, such as liveness detection and hard to forgery. Matching is a key step in palm vein verification. However, due to the problem of image rotation, shift and noise, current matching methods are difficult to reach high accuracy. This paper proposed an efficient refinement method for palm vein matching by adopting the iterative closest point (ICP) algorithm, which can accurately align the rotation and shift variations introduced in data acquisition. The experiment results on a large self-collected database show that the proposed method is effective and can greatly improve the accuracy of palm vein verification.

O O O O B O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O


Geodesic active regions and level set methods for supervised texture segmentation This paper presents a novel variational framework to deal with frame partition problems in Computer Vision. This framework exploits boundary and region-based segmentation modules under a curve-based optimization objective function. The task of supervised texture segmentation is considered to demonstrate the potentials of the proposed framework. The textured feature space is generated by filtering the given textured images using isotropic and anisotropic filters, and analyzing their responses as multi-component conditional probability density functions. The texture segmentation is obtained by unifying region and boundary-based information as an improved Geodesic Active Contour Model. The defined objective function is minimized using a gradient-descent method where a level set approach is used to implement the obtained PDE. According to this PDE, the curve propagation towards the final solution is guided by boundary and region-based segmentation forces, and is constrained by a regularity force. The level set implementation is performed using a fast front propagation algorithm where topological changes are naturally handled. The performance of our method is demonstrated on a variety of synthetic and real textured frames.

O O O O B I I O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

supervised texture segmentation
level set methods

gabor filters
mixture analysis
geodesic active contours
propagation of curves


Mappings and covering properties of topological groupoids The notion of fuzzy topological groupoid is defined. Stalk functions and G-sets are used to express and study basic properties of topological groupoids. Separability and compactness in topological groupoids are investigated. (C) 1999 Elsevier Science B.V. All rights reserved.

O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O

stalk function
continuity
g-set
gft(i)-axioms (i=0,1,2)


Multistage SIMO-model-based blind source separation combining frequency-domain ICA and time-domain ICA In this paper, single-input multiple-output (SIMO)-model-based blind source separation (BSS) is addressed, where unknown mixed source signals are detected at microphones, and can be separated, not into monaural source signals but into SIMO-model-based signals from independent sources as they are at the microphones. This technique is highly applicable to high-fidelity signal processing such as binaural signal processing. First. we provide an experimental comparison between two kinds of SIMO-model-based BSS methods, namely, conventional frequency-domain ICA with projection-back processing (FDICA-PB). and SIMO-ICA which was recently proposed by the authors. Secondly, we propose a new combination technique of the FDICA-PB and SIMO-ICA, which can achieve a higher separation performance than the two methods. The experimental results reveal that the accuracy of the separated SIMO signals in the simple SIMO-ICA is inferior to that of the signals obtained by FDICA-PB under low-quality initial value conditions, but the proposed combination technique can outperform both simple FDICA-PB and SIMO-ICA.

O O B I I O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

microphone array
independent component analysis
simo model


The open agent society: retrospective and prospective views It is now more than ten years since the EU FET project ALFEBIITE finished, during which its researchers made original and distinctive contributions to (inter alia) formal models of trust, model-checking, and action logics. ALFEBIITE was also a highly inter-disciplinary project, with partners from computer science, philosophy, cognitive science and law. In this paper, we reflect on the interaction between computer scientists and information and IT lawyers on the idea of the open agent society. This inspired a programme of research whose investigation into conceptual challenges has carried it from the logical specification of agent societies and dynamic norm-governed systems to self-organising electronic institutions, while developing several technologies for agent-based modelling and complex event recognition. The outcomes of this inter-disciplinary collaboration have also influenced current research into using the open agent society as a platform for socio-technical systems, and other collective adaptive systems. We present a number of research challenges, including the ideas of computational justice and polycentric governance, and explore a number of ethical, legal and social implications. We contend that, in order to address these issues and challenges, the continued inter-disciplinary collaboration between computer science and IT lawyers is critical.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

ethical legal and social implications (elsi)


A space-time-ensemble parallel nudged elastic band algorithm for molecular kinetics simulation A scalable parallel algorithm has been designed to study long-time dynamics of many-atom systems based on the nudged elastic band method, which performs mutually constrained molecular dynamics simulations for a sequence of atomic configurations (or states) to obtain a minimum energy path between initial and final local minimum-energy states. A directionally heated nudged elastic band method is introduced to search for thermally activated events without the knowledge of final states, which is then applied to an ensemble of bands in a path ensemble method for long-time simulation in the framework of the transition state theory. The resulting molecular kinetics (MK) simulation method is parallelized with a space-time-ensemble parallel nudged elastic band (STEP-NEB) algorithm, which employs spatial decomposition within each state, while temporal parallelism across the states within each band and band-ensemble parallelism are implemented using a hierarchy of communicator constructs in the Message Passing Interface library. The STEP-NEB algorithm exhibits good scalability with respect to spatial, temporal and ensemble decompositions on massively parallel computers. The MK simulation method is used to study low strain-rate deformation of amorphous silica. (C) 2007 Elsevier B.V. All rights reserved.

O O O O O O O O B I I O O O O O O O O O O O O O O O O O B I I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

nudged elastic band method
transition state theory
molecular kinetics simulation


numerical parameterization of affine varieties using In the present work, we extend the standard idea of numerical parameterization (i.e., parameterization by the numerical solution of initial-value problems (IVPs) for ordinary differential equations (ODEs) to affine varieties in ℂ; n for n ?2. We use these results with an efficient implementation in Maple to explore the use of numerical parameterization for the visualization of Riemann surfaces.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

numerical polynomial algebra
symbolic-numeric algorithms


Conditional connectivity of star graph networks under embedding restriction ? The n-dimensional star graph Sn is one of the most attractive interconnection networks of large scale multiprocessor systems. The k-embedding-restricted (edge) connectivity (?k(Sn)) ?k(Sn) of Sn is defined to be the cardinality of a minimum subset of (edges) nodes, if any, whose deletion disconnects Sn and each node of the remaining components lies in an undamaged k-dimensional substar Sk. In this paper, we investigate the k-embedding-restricted (edge) connectivity of Sn and determine the values of ?k(Sn) and ?k(Sn) for some ks.

O B O O O O O O O O O O O O O O O O O O O B I O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O


Minimization of joint reaction forces of kinematic chains by a multi-objective approach The paper describes a procedure of simultaneous minimization of joint reaction forces of planar kinematic chains. The best design is sought using the methods of mathematical programming. The optimization model of the kinematic chain is based on a multi-objective approach where the objective functions may be related to the generalized joint forces. The design variables are the geometric parameters of the links. The implementation of the optimization model is illustrated with two examples. The first example considers the minimization of joint reaction forces of an open loop system of a two-arm manipulator. The second example considers optimization of a closed loop system representing a four-bar mechanism being an actual part of a hydraulic support employed in the mining industry.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O B I O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

generalized joint forces
kinematic chain
mathematical programming


On the complexity of quantified linear systems In this paper, we explore the computational complexity of the conjunctive fragment of the first-order theory of linear arithmetic. Quantified propositional formulas of linear inequalities with (k?1) ( k ? 1 ) quantifier alternations are log-space complete in ? k P or ? k P depending on the initial quantifier. We show that when we restrict ourselves to quantified conjunctions of linear inequalities, i.e., quantified linear systems , the complexity classes collapse to polynomial time. In other words, the presence of universal quantifiers does not alter the complexity of the linear programming problem, which is known to be in P P . Our result reinforces the importance of sentence formats from the perspective of computational complexity.

O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

quantified linear systems
complexity classes


Atomistic origin of high-quality novel SiON gate dielectrics We have investigated the effect of the oxygen incorporation into SiN films by the first principles calculations. The calculated results show that the oxygen incorporation tends to generate defect states in SiN band gap by forming dangling bonds and floating bonds of Si. Based on the calculated results, it is also indicated that the high quality SiON film can be fabricated by suppressing the incorporation of O atoms into the SiN film, reproducing the reported experiments.

O O O O O O B I O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

first principles calculations
gate dielectrics


on the importance of understanding the strategies that developers use Understanding the strategies that developers use during coding activities is an important way to identify challenges developers face and the corresponding opportunities for tools, languages, or processes to better address the challenges and more effectively support the strategies. After creating a design, evaluation studies often measure task success, time, and bugs to argue that the design improves programmer productivity. Considering the strategies that developers use while conducting these studies increases the likelihood of a successful test and makes the results easier to generalize. Therefore, we believe that identifying strategies developers use is an important goal. Beyond identifying strategies, there are also research opportunities in better understanding how developers choose strategies.

O O O O O O B O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O B O O O O O O O O O O O B

developer questions
program comprehension


Adaptive fuzzy clustering based anomaly data detection in energy system of steel industry The accuracy of the acquired data is very significant for the decision-making process for the purpose of the safety and reliability of the energy system in steel industry. However, owing to the instability and vulnerability of industrial system of supervisory control and data acquisition (SCADA), the anomaly data usually exist in practice. In this study, considering the data feature of the energy system, we classify the anomalies as the trend anomaly for the pseudo-periodic data and the deviants for the generic data. As for the trend anomaly, a dynamic time warping (DTW) based method combining with adaptive fuzzy C means (AFCM) is proposed by referencing the similar industrial processes; while, as for the deviants detection, a k-nearest neighbor AFCM algorithm (KNN-AFCM) is designed here for the local anomaly detection for the generic data. To verify the effectiveness of the proposed method, the real-world energy data coming from a steel plant are employed to perform the experiments, and the results indicate that the proposed method exhibits a higher precision compared to the other methods for the anomaly detection.

O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I

energy system in steel industry
anomaly detection
fuzzy clustering
dynamic time warping


An exact algorithm for generating homogenous T-shape cutting patterns Both the material usage and the complexity of the cutting process should be considered in generating cutting patterns. This paper presents an exact algorithm for constrained two-dimensional guillotine-cutting problems of rectangles. It uses homogenous T-shape patterns to simplify the cutting process. Only homogenous strips are allowed, each of which contains rectangular blanks of the same size and direction. The sheet is divided into two segments. Each segment consists of strips of the same length and direction. The strip directions of the two segments are perpendicular to each other. The algorithm is based on branch and bound procedure combined with dynamic programming techniques. It is a bottom-up tree-search approach that searches the solution tree from the branches to the root. Tighter bounds are established to shorten the searching space. The computational results indicate that the algorithm is efficient both in computation time and in material usage.

O O O O O O O B O O O O O O O O O O B O O O O O O B O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

packing
cutting stock
constrained two-dimensional cutting


A fast and effective algorithm for the feedback are set problem A divide-and-conquer approach for the feedback are set is presented. The divide step is performed by solving a minimum bisection problem. Two strategies are used to solve minimum bisection problem: A heuristic based on the stochastic evolution methodology, and a heuristic based on dynamic clustering. Empirical results are presented to compare our method with other approaches. An algorithm to construct test cases for the feedback are set problem with known optimal number of feedback arcs, is also presented.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

feedback set
acyclic subgraph
consistent inequalities


How to deal with the unbounded in optimization: Theory and algorithms The aim of this survey is to show how the unbounded arises in optimization problems and how it leads to fundamental notions which are not only useful for proving theoretical results such as convergence of algorithms and the existence of optimal solutions, but also for constructing new methods. (C) 1997 The Mathematical Programming Society, Inc. Published by Elsevier Science B.V.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I I O O O O O O O O O O O O O O O O O O

convex and linear programming
convex analysis
recession functions
penalty and barrier methods


Averaging and oversampling correlator receiver with input quantization Correlation is a fundamental technique to detect signals buried in noise. However, due to noise, the fluctuations of the output signal may be significant and the detection of the desired signal can then fail. It is known that a simple one-bit correlator receiver can give nearly identical performance to the full precision correlator in determining time delays in medium signal-to-noise ratio situations, when averaging several successive correlation signals. An oversampled and averaged version of the correlator, with input quantization to a low number of bits, is studied here using simulation. It is demonstrated that, by oversampling the received signal at a multiple of the correlation code clock rate and averaging over several successive samples, performance similar to that of the full precision correlator may be attained to in low SNR situations.

B O B O O O O B B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O B O O O O O O O O O O O B O O O O O O O O O O O O O O O O B O O O O O O O O B O O O O B O O O O O O O O O O O O O O O O O O O O O

correlation quantization averaging oversampling

signal processing
one-bit correlator
signal-to-noise ratio


Performance of Dual Hop Relay System in the Presence of a Correlated Interferer Through Nakagami Fading Channel This paper provides a unified approach for accurate numerical evaluations of the bit error rate of dual hop amplify and forward system in the presence of interference. Existence of independent or correlated interferer in one or both hops is assumed. Nakagami fading channel with integer and non-integer fading depth m is assumed. Depicted results show that correlation has insignificant effect relative to independent situation when the interferer power is equal to that of the desired signal. It can give relative improvement if the interferer is weaker (?12dB) than the desired signal. Results showing appreciable improvement on the employment of diversity at both of the relay and destination are also displayed.

O O B I O O O O O O O O O O B I O O O O O O O O O O O O O O O O O B I B I I O O O O O B O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

amplify and forward
dual hop
interference
nakagami fading


congressional samples for approximate answering of group-by queries In large data warehousing environments, it is often advantageous to provide fast, approximate answers to complex decision support queries using precomputed summary statistics, such as samples. Decision support queries routinely segment the data into groups and then aggregate the information in each group ( group-by queries). Depending on the data, there can be a wide disparity between the number of data items in each group. As a result, approximate answers based on uniform random samples of the data can result in poor accuracy for groups with very few data items, since such groups will be represented in the sample by very few (often zero) tuples. In this paper, we propose a general class of techniques for obtaining fast, highly-accurate answers for group-by queries. These techniques rely on precomputed non-uniform (biased) samples of the data. In particular, we propose congressional samples , a hybrid union of uniform and biased samples. Given a fixed amount of space, congressional samples seek to maximize the accuracy for all possible group-by queries on a set of columns. We present a one pass algorithm for constructing a congressional sample and use this technique to also incrementally maintain the sample up-to-date without accessing the base relation. We also evaluate query rewriting strategies for providing approximate answers from congressional samples. Finally, we conduct an extensive set of experiments on the TPC-D database, which demonstrates the efficacy of the techniques proposed.

O O O O O O O B O O B O B O O O O O O O O O O O B I B O O O B O O O B I B O O O B O O O O B O O O O B O O B O O O B O O O O O O O O O O B O O O B O O O O O O O O O O O O B O O O O B O O O O O B O O O O O O O O O O O O O O O O O O B O O O B B O O O O O O O O O B O O O O O O O O O O B O O O O O O O O B O O O O O O O O O O O B O O O O O O B O O O O B O O O O O O O O O O B O O O O O O B O O O O O O O O O O O O O B O O O O O B O O O O O O O O O O O O O O O O O O B O O O O O O O O

statistics
use
general
group
paper
strategies
accuracy
environments
space
aggregate
data
queries
relation
decision support
algorithm
database
hybrid
class

approximation
maintainability
experience
bias
informal
sampling
evaluation
random sample
query rewrite
segmentation
complexity
data warehousing


body sensor networks based sensor fusion for cardiovascular biosignal predictions A Multivariate Autoregressive (MAR) model based sensor fusion technique is developed in this work to improve the reliability and accuracy of cardiovascular biosignal prediction by taking advantages of combining sensory data from heterogeneous biosensors in a network. The importance and potential applications of sensor fusion in body sensor networks are introduced. Real-world data from MIT-BIH multi-parameter database MIMIC (Multi-parameter Intelligent Monitoring for Intensive Care) is used to verify the MAR model performance. The effects of model order number and involved biosignal number are studied. The experiments also show that ECG signals can be partially recovered from other biosignals even if the ECG input is completely missing.

O O O O B I O B I I O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

sensor fusion
cardiovascular biosignal predictions

body sensor networks (bsns)
multivariate autoregressive (mar) model


Prototype AWA: design and implementation of a high speed ATM wireless access system using 25 GHz band This paper describes the design and implementation of a prototype ATM Wireless Access (AWA) system that provides high speed ATM transport capability for tetherless multimedia services. The prototype AWA uses the 25 GHz band for experimental purpose because of its support of high speed transmission. This paper describes the design concept of the prototype AWA as well as key technologies that allow it to achieve high speed and high quality ATM-based transmission.

wireless atm
multi-media wireless communication
high-speed wireless access
system design


The role of active locomotion in space perception It has been shown that active control of locomotion increases accuracy and precision of nonvisual space perception, but psychological mechanisms of this enhancement are poorly understood. The present study explored a hypothesis that active control of locomotion enhances space perception by facilitating crossmodal interaction between visual and nonvisual spatial information. In an experiment, blindfolded participants walked along a linear path under one of the following two conditions: (1) They walked by themselves following a guide rope and (2) they were led by an experimenter. Subsequently, they indicated the walked distance by tossing a beanbag to the origin of locomotion. The former condition gave participants greater control of their locomotion and thus represented a more active walking condition. In addition, before each trial, half the participants viewed the room in which they performed the distance perception task. The other half remained blindfolded throughout the experiment. Results showed that although the room was devoid of any particular cues for walked distances, visual knowledge of the surroundings improved the precision of nonvisual distance perception. Importantly, however, the benefit of preview was observed only when participants walked more actively. This indicates that active control of locomotion allowed participants to better utilize their visual memory of the environment for perceiving nonvisually encoded distance, suggesting that active control of locomotion served as a catalyst for integrating visual and nonvisual information to derive spatial representations of higher quality.

O O O O B O B I O O O O O O O O B O O O O O O B I O O O O O O O O O O O O O O O O O O O B O B I O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O B I O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O

space perception
locomotion
visual memory
crossmodal interaction


comparing effective and ineffective behaviors of student programmers This paper reports on a quantitative evaluation of five years of data collected in the first three programming courses at Virginia Tech. The dataset involves a total of 89,879 assignment submissions by 1,101 different students. Assignment results were partitioned into two groups: scores above 80\% (A/B) and scores below 80\% (C/D/F). To investigate student behaviors that result in differing levels of achievement, all students who consistently received A/B scores and all students who consistently received C/D/F scores were removed from the dataset. A within-subjects comparison of the scores received by the remaining individuals was performed. Further, time and code-size data that is difficult to compare directly between different courses was normalized. This study revealed several significant results. When students received A/B scores, they started earlier and finished earlier than when the same students received C/D/F scores. They also wrote slightly more program code. They did not appear to spend any more time on their work, however. Approximately two-thirds of the A/B scores were received by individuals who started more than a day in advance of the deadline, while approximately two-thirds of the C/D/F scores were received by individuals who started on the last day or later. One possible explanation is that students who start earlier simply have more time to seek assistance when they get stuck.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

programming assignment
study habits
student performance
programmer productivity


Domain-theoretical models of parametric polymorphism We present a domain-theoretical model of parametric polymorphism based on admissible per's over a domain-theoretical model of the untyped lambda calculus. The model is shown to be a model of Abadi & Plotkin's logic for parametricity, by the construction of an LAPL-structure as defined by the authors in [L. Birkedal, R.E. Mogelberg, R.L. Petersen, Parametric domain-theoretical models of polymorphic intuitionistic/linear lambda calculus, in: M. Escardo, A. Jung, M. Mislove (Eds.), Proceedings of Mathematical Foundations of Programming Semantics 2005, vol. 155, 2005, pp. 191-217; L. Birkedal, R.E. Mogelberg, R.L. Petersen, Category theoretical models of linear Abadi & Plotkin logic, 2006 (submitted for publication)]. This construction gives formal proof of solutions to a large class of recursive domain equations, which we explicate. As an example of a computation in the model, we explicitly describe the natural numbers object obtained using parametricity. The theory of admissible per's can be considered a domain theory for (impredicative) polymorphism. By studying various categories of admissible and chain complete per's and their relations, we discover a picture very similar to that of domain theory. (C) 2007 Elsevier B.V. All rights reserved.

O O O B I O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O


Feature-Adaptive GPU Rendering of Catmull-Clark Subdivision Surfaces We present a novel method for high-performance GPU-based rendering of Catmull-Clark subdivision surfaces. Unlike previous methods, our algorithm computes the true limit surface up to machine precision, and is capable of rendering surfaces that conform to the full RenderMan specification for Catmull-Clark surfaces. Specifically, our algorithm can accommodate base meshes consisting of arbitrary valence vertices and faces, and the surface can contain any number and arrangement of semisharp creases and hierarchically defined detail. We also present a variant of the algorithm which guarantees watertight positions and normals, meaning that even displaced surfaces can be rendered in a crack-free manner. Finally, we describe a view-dependent level-of-detail scheme which adapts to both the depth of subdivision and the patch tessellation density. Though considerably more general, the performance of our algorithm is comparable to the best approximating method, and is considerably faster than Stam's exact method.

O O O O O B I O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

algorithms
catmull-clark subdivision surfaces