C++ Support and Applications for Embedded Multicore DSP Systems In recent years embedded systems have entered the multicore era. As the number of cores keeps growing in embedded systems, it becomes more important to provide programming support which considers embedded system constraints and in the meanwhile helps utilize multicore systems. So far though C still dominates embedded programming, C++ is gaining in importance in parallel programming. It is promising to support C++ for embedded multicore systems. However, embedded systems usually have tight resource budgets, and C++ is commonly considered having huge code size that embedded systems can not afford. Therefore, in this paper we investigate the code size requirement of a C++ library and propose a layered design to provide a code size aware library support. On the other hand, to utilize embedded multicore systems, we employ C++ linguistic features to facilitate embedded multicore programming. With C++, we incorporate high-level abstractions and design patterns into the programming support to enhance low-level programming APIs that can be used to exploit DSPs, SIMD instructions, and DMAs on embedded multicore systems. At last, we evaluate our C++ support with a Blur and a JPEG program. Our result on a dual-DSP platform shows that we can obtain speedups of 3.32 and 3.09 for the Blur and JPEG program, respectively.

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

c++ library
programming models
parallel design patterns


FieldBook and GeoDatabase: tools for field data acquisition and analysis We introduce FieldBook and GeoDatabase, 2 new and effective tools for geologic field data acquisition and analysis.;FieldBook is an application for Apple's Newton MessagePad: Geological data collected at the outcrop, including notes and drawings, can be entered directly and on-site. If he formalization of the multiparameter information leads directly to a consistent database. This procedure results in a complete, up-to-date database where all information collected by different researchers in a project is available anytime, and no data are lost. CeoDatabase is an application based on FileMaker(TM) Pro, representing the, FieldBook interface on PC/Macintosh. GeoDatabase provides extensive search possibilities and strong export features that are needed for field-data analysis, either in the field or in the office. It can be used as a central database within a local network with several users on either PC or a Macintosh. FieldBook and GeoDatabase both are simple to use, yet they satisfy the demands of field campaigns involving numerous scientists. Applications of field projects in the crystalline basement of the Salalah area and the Masirah ophiolite are given. (C) 1999 Elsevier Science 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 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 B 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 O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

geologic mapping
field data capture
data management


Reliable resources brokering scheme in wireless grids based on non-cooperative bargaining game Wireless computational grids are evolving due to rapid growth in wireless devices to provide any time any where computing and communication services. Wireless devices are considered as important resources for job execution in a wireless grid. However, they are unreliable due to unstable wireless connections, frequent mobility, and device resource constraints such as limited processing capacity, limited battery life, low communication bandwidth, etc. Consumers and providers in a wireless grid have potential conflicting interests: consumers prefer reliable resources at minimum cost for job execution whereas providers prefer efficient utilization of resources with a maximum profit. Hence it is necessary to design a resource brokering mechanism that assures job(s) execution and satisfies needs of consumers and providers. This paper proposes a software agent based resource brokering scheme that employs a resource brokering agency consisting of a set of software agents which discover and recommend reliable devices, negotiate resource cost using non-cooperative bargaining game, and schedule jobs. Device reliability is modeled by using parameters like processing rate, memory, bandwidth and battery power. Discount function is employed in bargaining game based on job deadline, previous offers of an opponent, and dynamics in the grid market. Adaptive negotiation process is applied by exercising different discount strategies (aggressive or conservative or linear) based on the negotiation status of a player. The scheme is simulated to evaluate performance parameters like resource utilization rate, expected profit, job completion time and job execution rate. We observed that the proposed scheme performs better than the existing resource brokering scheme.

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

wireless grid
agent
negotiation
resource brokering


Optic disk feature extraction via modified deformable model technique for glaucoma analysis A deformable-model based approach is presented in this paper for robust detection of optic disk and cup boundaries. Earlier work on disk boundary detection up to now could not effectively solve the problem of vessel occlusion. The method proposed here improves and extends the original snake, which is essentially a deforming-only technique, in two aspects: knowledge-based clustering and smoothing update. The contour deforms to the location with minimum energy, and then self-clusters into two groups, i.e., edge-point group and uncertain-point group, which are finally updated by the combination of both local and global information. The modifications enable the proposed algorithm to become more accurate and robust to blood vessel occlusions, noises, ill-defined edges and fuzzy contour shapes. The comparative results on the 100 testing images show that the proposed method achieves better success rate (94%) when compared to those obtained by GVF-snake (12%) and modified ASM (82%). The proposed method is extended to detect the cup boundary and then extract the disk parameters for clinical application, which is a relatively new task in fundus image processing. The resulted cup-to-disk (C/D) ratio shows good consistency and compatibility when compared with the results from Heidelberg Retina Tomograph (HRT) under clinical validation.

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 B I O B 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 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 B 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

boundary detection
optic disk
cup
snake
deformable model
fundus image


Performance analysis of exponential backoff New analytical results are given for the performance of the exponential backoff (EB) algorithm. Most available studies on EB focus on the stability of the algorithm and little attention has been paid to the performance analysis of EB. In this paper, we analyze EB and obtain saturation throughput and medium access delay of a packet for a given number of nodes N. The analysis considers the general case of EB with backoff factor r; binary exponential backoff (BEB) algorithm is the special case with r = 2. We also derive the analytical performance of EB with maximum retry limit M (EB-M), a practical version of EB. The accuracy of the analysis is checked against simulation results.

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

beb
exponential backoff
medium access delay
performance analysis
throughput


Simple universal reversible cellular automata in which reversible logic elements can be embedded A reversible cellular automaton (RCA) is a computing model having a property analogous to physical reversibility. We investigate the problem of finding simple RCAs in which any circuit composed of rotary elements (REs) can be embedded. Since an RE is known to be a universal reversible logic element, such RCAs are also universal in this respect. In this paper, after giving a survey of known results on RE and its implementation in RCAs, we propose a new RCA model in which REs and some signal routing elements can be embedded. The new model has a simpler local transition function (in the sense it is described by fewer rules) than the previous one, though the number of states is the same. In addition, the patterns realizing an RE and signal routing elements are smaller than those of the previous model.

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 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

reversible cellular automaton
reversible logic element


A single stage hot forging process and die set of alternator poles A single stage hot forging process and die set of alternator poles are put forward in this paper, the heated billet can be forged by only one press in a special die set, which has a moveable mandrel and ring die. The process is analyzed by finite element method(FEM) and experiment. The effects of mandrel on the mode of metal flow and forging load are discussed. The result shows that a well-shaped product can be forged successfully using a lower forging load than that of conventional precision forging.

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


Extraction of features using M-band wavelet packet frame and their neuro-fuzzy evaluation for multitexture segmentation In this paper, we propose a scheme for segmentation of multitexture images. The methodology involves extraction of texture features using an overcomplete wavelet decomposition scheme called discrete M-band wavelet packet frame (DMbWPF). This is followed by the selection of important features using a neuro-fuzzy algorithm under unsupervised learning. A computationally efficient search procedure is developed for finding the optimal basis based on some maximum criterion of textural measures derived from the statistical parameters for each of the subbands. The superior discriminating capability of the extracted features for segmentation of various texture images over those obtained by several existing methods is established.

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

texture segmentation
m-band wavelet packet frames
feature selection
fuzzy feature evaluation index
neural networks


Optimization of lipid production with a genome-scale model of Yarrowia lipolytica Yarrowia lipolytica is a non-conventional yeast that is extensively investigated for its ability to excrete citrate or to accumulate large amounts of storage lipids, which is of great significance for single cell oil production. Both traits are thus of interest for basic research as well as for biotechnological applications but they typically occur simultaneously thus lowering the respective yields. Therefore, engineering of strains with high lipid content relies on novel concepts such as computational simulation to better understand the two competing processes and to eliminate citrate excretion.

O O 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 B O

flux balance analysis
oleaginous yeast
oxygen limitation
fed-batch fermentation


Stability analysis of generalized impulsive functional differential equations In this paper, the stability problem for a class of generalized impulsive functional differential equations in which the state variables on the impulses are related to the time delay is studied. By using Lyapunov functions and Razumikhin techniques, several global exponential stability and uniform stability criteria are derived, which can be applied to impulsive functional differential equations with any time delays. The results obtained improve and extend those in earlier publications. Moreover, our results show that delay differential equations can be exponentially stabilized by impulses in which the state variables are related to the time delay. Finally, two examples are given to illustrate the effectiveness and advantages of the results obtained. (C) 2011 Elsevier Ltd. All rights reserved.

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


Nonlinear dynamic system identification and control via constructivism inspired neural network This paper deals with a novel idea of identification of nonlinear dynamic systems via a constructivism inspired neural network. The proposed network is known as growing multi-experts network (GMN). In GMN, the problem space is decomposed into overlapping regions by expertise domain and local expert models are graded according to their expertise level. The network output is computed by the smooth combination of local linear models. In order to avoid over-fitting problem, GMN deploys a redundant experts removal algorithm to remove the redundant local experts from the network. In addition, growing neural gas (GNG) algorithm is used to generate an induced Delaunay triangulation that is highly desired for optimal function approximation. A variety of examples are taken from literature to establish the efficacy of GMN. Discrete time nonlinear dynamic system modeling and water bath temperature control have been found to give excellent results via this novel neural network.

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 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

growing neural gas
system identification


Accuracy refinement algorithm for mobile target location tracking by radio signal strength indication approach A novel RSSI (Received Signal Strength Indication) refinement algorithm is proposed to enhance the resolution for indoor and outdoor real-time location tracking system. The proposed refinement algorithm is implemented in two separate phases. During the first phase, called the pre-processing step, RSSI values at different static locations are collected and processed to build a calibrated model for each reference node. Different measurement campaigns pertinent to each parameter in the model are implemented to analyze the sensitivity of RSSI. The propagation models constructed for each reference nodes are needed by the second phase. During the next phase, called the runtime process, real-time tracking is performed. Smoothing algorithm is proposed to minimize the dynamic fluctuation of radio signal received from each reference node when the mobile target is moving. Filtered RSSI values are converted to distances using formula calibrated in the first phase. Finally, an iterative trilateration algorithm is used for position estimation. Experiments relevant to the optimization algorithm are carried out in both indoor and outdoor environments and the results validated the feasibility of proposed algorithm in reducing the dynamic fluctuation for more accurate position estimation.

O B I O O O B I 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 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 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 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 I

refinement algorithm
location tracking
smoothing algorithm
position estimation

received signal strength indication (rssi)


MACHINE LEARNING ON CONGESTION ANALYSIS BASED REAL-TIME NAVIGATION SYSTEM In the metropolitan region, most congestion or traffic jams are caused by the uneven distribution of traffic flow that creates bottleneck points where the traffic volume exceeds the road capacity. Additionally, unexpected incidents are the next most probable cause of these bottleneck regions. Moreover, most drivers are driving based on their empirical experience without awareness of real-time traffic situations. This unintelligent traffic behavior can make the congestion problem worse. Prediction based route guidance systems show great improvements in solving the inefficient diversion strategy problem by estimating future travel time when calculating accurate travel time is difficult. However, performances of machine learning based prediction models that are based on the historical data set degrade sharply during a congestion situation. This paper develops a new navigation system for reducing travel time of an individual driver and distributing the flow of urban traffic efficiently in order to reduce the occurrence of congestion. Compared with previous route guidance systems, the results reveal that our system, applying the advanced multi-lane prediction based real-time fastest path (AMPRFP) algorithm, can significantly reduce the travel time especially when drivers travel in a complex route environment and face frequent congestion problems. Unlike the previous system,(1) it can be applied either for single lane or multi-lane urban traffic networks where the reason for congestion is significantly complex. We also demonstrate the advantages of this system and verify the results using real highway traffic data and a synthetic experiment.

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

congestion
fastest path
machine learning
urban traffic networks

traffic jam
real-time traffic
support vector regression (svr)
travel time prediction
multi-lane


Robust stability of discrete-time stochastic neural networks with time-varying delays ? In this paper, the global exponential stability problem is studied for a class of discrete-time uncertain stochastic neural networks with time delays. The stability analysis problem is investigated, for the first time, for such kind of neural networks. In the neural network model, the parameter uncertainties are norm-bounded, the neural networks are subjected to stochastic disturbances described in terms of a Brownian motion, and the delay is time-varying. By utilizing a LyapunovKrasovskii functional and using some well-known inequalities, we convert the addressed stability analysis problem into the feasibility problem of several linear matrix inequalities (LMIs). Different from the commonly used matrix norm theories (such as the M-matrix method), a unified LMI approach is developed to establish sufficient conditions for the neural networks to be globally, robustly, exponentially stable. A numerical example is provided to show the usefulness of the proposed global stability condition.

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

stochastic neural networks
exponential stability

discrete neural networks
uncertain neural networks
time-varying delays
linear matrix inequality


Distributed Beamforming in Wireless Multiuser Relay-Interference Networks With Quantized Feedback We study fixed data rate communication schemes for wireless relay-interference networks with any number of transmitters, relays, and receivers. The transmitters and the relays have individual short-term power constraints. We analyze both amplify-and-forward (AF) and decode-and-forward (DF) relaying strategies with a two channel use quantized network beamforming protocol. We design the quantizer of the channel state information to minimize the probability that at least one receiver incorrectly decodes its desired symbol(s). Correspondingly, we introduce a generalized diversity measure that encapsulates the conventional one as the first-order diversity. Additionally, it incorporates the second-order diversity, which is concerned with the transmitter power dependent logarithmic terms that appear in the error rate expression. We first show that for AF relays, the maximal achievable diversity in the presence of interference is strictly less than the transmit diversity bound in terms of the second-order diversity. We then prove that it is possible to achieve the transmit diversity bound using DF relays as if there is no interference and as if coding over an arbitrary number of channel uses is allowed. Relay selection provides the best possible diversity gain for both relaying strategies. Finally, we show that all the aforementioned diversity gains can be achieved using distributed decision making with asymptotically zero feedback rate per receiver. Such a performance is made possible by a special distributed quantizer design method we have called localization.

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 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 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 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

distributed vector quantization
wireless relay network


ADALINE based robust control in robotics: a Riemann-Liouville fractional differintegration based learning scheme This paper presents an approach to improve the performance of intelligent sliding model control achieved by the use of a fundamental constituent of soft computing, named Adaptive Linear Element (ADALINE). The proposed scheme is based on the fractional calculus. A previously considered tuning scheme is revised according to the rules of fractional order differintegration. After a comparison with the integer order counterpart, it is seen that the control system with the proposed adaptation scheme provides (1) better tracking performance, (2) suppression of undesired drifts in parameter evolution and (3) a very high degree of robustness and insensitivity to disturbances. The claims are justified through some simulations utilizing the dynamic model of a two degrees of freedom (DOF) direct drive robot arm and overall, the contribution of the paper is to introduce the fractional order calculus into a robust and nonlinear control problem with some outperforming features that are absent when the integer order differintegration operators are adopted.

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

fractional adaptation laws
adaptive sliding mode control


Computational method for the point cluster analysis on networks We present a general framework of hierarchical methods for point cluster analysis on networks, and then consider individual clustering procedures and their time complexities defined by typical variants of distances between clusters. The distances considered here are the closest-pair distance, the farthest-pair distance, the average distance, the median-pair distance and the radius distance. This paper will offer a menu for users to choose hierarchical clustering algorithms on networks from a time complexity point of view.

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

network cluster analysis
hierarchical cluster analysis
hot spot
closest-pair distance
farthest-pair distance
median-pair distance


reducing irrelevant trace variations Identifying truly distinct traces is crucial for the performance and practicality of many dynamic analysis activities. For example, given a trace pool resulting from program failures, identifying the set of distinct traces can reduce the debugging effort by more quickly producing a smaller set of candidate fault locations. The process of discriminating valuable traces, however, is subject to the presence of irrelevant variations in the trace constitution, i.e., the sequence of events in a trace, that can make a trace appear unique when it is not, leading to the retention of a trace that adds no value. In this paper we present an approach to address inconsequential and potentially detrimental trace variations. The approach decomposes traces into segments on which irrelevant variations caused by event ordering or repetition can be detected and removed. The approach is illustrated on two well-known client dynamic analyses and is supported by an infrastructure to explore the approach

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

trace simplification
trace analysis
execution traces


The study of drug-reaction relationships using global optimization techniques In this paper we develop an optimization approach for the study of adverse drug reaction (ADR) problems. This approach is based on drug-reaction relationships represented in the form of a vector of weights, which can be defined as a solution to some global optimization problem. Although it can be used for solving many ADR problems, we concentrate on two of them here: the accurate identification of drugs that are responsible for reactions that have occurred, and drug-drug interactions. Based on drug-reaction relationships, we formulate these problems as an optimization problem. The approach is applied to cardiovascularn-type reactions from the Australian Adverse Drug Reaction Advisory Committee (ADRAC) database. Software based on this approach has been developed and could have beneficial use in prescribing.

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

global optimization
adverse drug reaction

multi-label classification
suspected drugs
drug-drug interaction


First-order approximation of GramSchmidt orthonormalization beats deflation in coupled PCA learning rules In coupled learning rules for principal component analysis, eigenvectors and eigenvalues are simultaneously estimated in a coupled system of equations. Coupled single-neuron rules have favorable convergence properties. For the estimation of multiple eigenvectors, orthonormalization methods have to be applied, either full GramSchmidt orthonormalization, its first-order approximation as used in Oja's stochastic gradient ascent algorithm, or deflation as in Sanger's generalized Hebbian algorithm. This paper reports the observation that a first-order approximation of GramSchmidt orthonormalization is superior to the standard deflation procedure in coupled learning rules. The first-order approximation exhibits a smaller orthonormality error and produces eigenvectors and eigenvalues of better quality. This improvement is essential for applications where multiple principal eigenvectors have to be estimated simultaneously rather than sequentially. Moreover, loss of orthonormality may have an harmful effect on subsequent processing stages, like the computation of distance measures for competition in local PCA methods.

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

principal component analysis
coupled learning rules
orthonormalization
deflation


A participatory ergonomics intervention to reduce risk factors for low-back disorders in concrete laborers Construction laborers rank high among occupational groups with work-related musculoskeletal injuries involving time way from work. The goals of this project were to: (1) introduce an ergonomic innovation to decrease the risk of low-back disorder (LBD) group membership, (2) quantitatively assess exposure, and (3) apply a participatory intervention approach in construction. Laborers manually moving a hose delivering concrete to a placement site were evaluated. The hypothesis tested was that skid plates would prevent hose joints from catching on rebar matting, and the hose would slide more easily. This would decrease the need for repetitive bending and use of excessive force. Four laborers were evaluated wearing the Lumbar Motion Monitor (LMM), a tri-axial electrogoniometer that records position, velocity and acceleration. Workers were measured during three comparable concrete pours. Worker perceptions of the innovation utility and exertion were surveyed. During initial use of skid plates, flexion increased significantly (p<0.001) while velocity, acceleration and moments did not change. After implementing a worker modification, low back velocity, acceleration and moments were significantly reduced (p<0.05). Reductions in these factors have been associated with decreased risk of belonging to an occupational group with LBDs. Use of secured skid plates during horizontal concrete hose movement may in part decrease the risk of LBD group membership among concrete laborers. Crew participation resulted in skid plates being a more effective intervention. The LMM is a promising tool for quantitative assessment in construction.

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

low-back disorder risk
trunk kinematics
workplace interventions


Fast simulations of stochastic dynamical systems A number of features relevant to stochastic dynamical systems, such as moments of solutions and first passage times, can be efficiently computed resorting to sequences of quasi-random numbers (low-discrepancy sequences). This method represents an alternative choice to the use of pseudorandom numbers, provided that a special care is paid to keep sufficiently uncorrelated as well as uniform the former sequences.

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


Computer modeling on the tautomerization of sulbactam intermediate in SHV-1 ?-lactamases: E166A mutant vs. wild type We present a theoretical study for the tautomerization of sulbactam intermediates in different SHV-1 ?-lactamases: E166A and wild-type (WT). Molecular dynamics (MD) simulations were employed and hydrogen bonds network around active site was found different between the WT and E166A acyl-enzymes. In E166A, Asn170 restricts the C5 C6 bond rotation, thus stabilizes the dihedral angle N4 C5 C6 C7 of imine to a trans conformation. The DFT calculations (B3LYP/6-31+G* and B3LYP/6-31++G**) were performed on tautomerization reactions. Two mechanisms including direct and stepwise proton transfer reactions were proposed based on the MD results. In E166A, the substrate carboxyl group acts as a relay station which assists the proton transfer with a very low energy barrier. However, in WT, such stepwise mechanism is difficult to proceed because of the large separation between C6 and substrate carboxyl group. Our results explain why E166A SHV-1 ?-lactamases forms greater population of trans-enamine than WT.

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

molecular dynamics simulations
density functional theory
?-lactamases


An asynchronous copy-back cache architecture Over the past 10 years asynchronous design has re-emerged as a viable alternative to clocked design with mounting evidence of competitive performance, power efficiency and electromagnetic compatibility compared to the more mainstream synchronous style. This paper presents an asynchronous cache architecturethe logical choice for use with an asynchronous microprocessor where a synchronous cache compromises the asynchronous benefits of the processor. The design presented here provides the processor with a unified, dual-ported view of its memory subsystem using multiple interleaved blocks. Each block has separate instruction and data line-buffers acting as level-zero (L0) cache making cache access time highly variable. The cache employs a copy-back write strategy to support a high-performance embedded processor core. The design is optimised for the Amulet3 microprocessor core, the third fully asynchronous implementation of the ARM architecture, but the techniques employed are generally applicable to any asynchronous processor.

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


Face tracking with automatic model construction This paper describes an active model with a robust texture model built on-line. The model uses one camera and it is able to operate without active illumination. The texture model is defined by a series of clusters, which are built in a video sequence using previously encountered samples. This model is used to search for the corresponding element in the following frames. An on-line clustering method, named leaderP is described and evaluated on an application of face tracking. A 20-point shape model is used. This model is built offline, and a robust fitting function is used to restrict the position of the points. Our proposal is to serve as one of the stages in a driver monitoring system. To test it, a new set of sequences of drivers recorded outdoors and in a realistic simulator has been compiled. Experimental results for typical outdoor driving scenarios, with frequent head movement, turns and occlusions are presented. Our approach is tested and compared with the Simultaneous Modeling and Tracking (SMAT) [1], and the recently presented Stacked Trimmed Active Shape Model (STASM) [2], and shows better results than SMAT and similar fitting error levels to STASM, with much faster execution times and improved robustness.

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 B I 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 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

face tracking
robust fitting
driver monitoring

appearance modeling
incremental clustering


methodology for teaching introductory computer science In the last few years it has been generally recognized that teaching programming involves more than describing a new FORTRAN statement each day and providing programming problems to be coded. The concepts of disciplined programming and the accompanying interest in the problem solving process, coupled with the increasing economic desirability of constructing correct and maintainable software has resulted in significant attention being focused on what should be taught, and, to a lesser extent, on how this is best accomplished. In order to discuss how an introductory programming course is taught, it is essential to first establish a set of objectives for such a course. Some of these objectives are obvious and generally agreed upon, others are engendered by the academic environment in which this particular course exists. We first state the objectives and then comment on their appropriateness and interrelation.

B O B O B I 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 B 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 B 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

computer science
attention
process
teaching
introductory programming
software
order
methodology


Building and using a medical ontology for knowledge management and cooperative work in a health care network In the context of a health care network, we describe our method for reconstitution of a medical ontology via the translation of a medical database (DB) towards RDF(S) language. Then we show how we extended this ontology among others through natural language processing of a textual corpus. Then, we present the construction of a tool called Virtual Staff, enabling a cooperative diagnosis by some of the health care network actors, by relying on this medical ontology and on the creation of SOAP and QOC graphs.

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 B O B O

ontologies
semantic web
cooperation
medical application


An efficient solution to improve the spectral noise suppression rules Typical spectral noise suppression rules employ a multiplicative gain function in the frequency domain. In this paper, we propose a modified gain function to improve the speech enhancement. The general principle is based on a theoretical development of the classical gain function in order to derive an efficient estimator for the noise reduction system. The idea combines the performances of spectral subtraction method and statistical model estimator. The obtained combination involves two parameters. These parameters control the rate of noise reduction and speech distortion. Performances of the idea were evaluated using a number of tests in various environments through speech distortion measurement. Experimental evaluations show that the modified gain function yields better results as compared to the conventional gain functions.

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

speech enhancement
noise reduction
statistical model


Body image 2.0: Associations between social grooming on Facebook and body image concerns This study examined the association between social media use and body image. Time spent on Facebook was not related to body image concerns. Social grooming behaviors were correlated with the drive for thinness. Appearance comparison mediated this relationship.

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

social grooming
appearance comparison
body image


ROBUST DECENTRALIZED H-2 CONTROL OF MULTI-CHANNEL DESCRIPTOR SYSTEMS WITH NORM-BOUNDED PARAMETRIC UNCERTAINTIES This paper considers a robust decentralized H-2 control problem for multi-channel descriptor systems. The uncertainties are assumed to be time-invariant, norm-bounded, and exist in both the system and control input matrices. Our interest is focused on dynamic output feedback. A necessary and sufficient condition for an uncertain multi-channel descriptor system to be robustly stabilizable with a specified H-2 norm is derived in terms of a strict nonlinear matrix inequality (NMI), that is, an NMI with no equality constraint. A two-stage homotopy method is proposed to solve the NMI iteratively. First, a decentralized controller for the nominal descriptor system is computed by imposing block-diagonal constraints on the coefficient matrices of the controller gradually. Then, the decentralized controller is modified, again gradually, to cope with the uncertainties. On each stage, groups of variables are fixed alternately at the iterations to reduce the NMI to linear matrix inequalities (LMIs). An example is given to show the efficiency of this method.

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

descriptor systems
homotopy method
nonlinear matrix inequality

decentralized control
parametric uncertainty


Structural design and analysis for a sensor-integrated ball bearing The structural design issues associated with the development of a sensor-integrated ball bearing were investigated. A finite element model was established to analyze the structural integrity of a ball bearing whose outer ring was modified to accommodate a miniaturized load sensor module. The sensor module was designed to monitor dynamic load variations within the bearing, which is an important indicator of a bearings safe operation. This structural integration of intelligence is significant in that it bring's automated, on-line, self-diagnosis capability to a dynamic system for which reliable, safe operation is of critical importance. A design tool was developed to evaluate the effect of outer ring modification on the dynamic load-carrying capability of the bearing. The tool also provided quantitative guidelines for the design of load and other types of sensor modules that will be structurally embedded into the outer ring of a conventional bearing for industrial applications.

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

finite element analysis
integrated sensing
self-diagnosis
electro-mechanical modeling


tropical cyclone event sequence similarity search via dimensionality reduction and metric learning The Earth Observing System Data and Information System (EOSDIS) is a comprehensive data and information system which archives, manages, and distributes Earth science data from the EOS spacecrafts. One non-existent capability in the EOSDIS is the retrieval of satellite sensor data based on weather events (such as tropical cyclones) similarity query output. In this paper, we propose a framework to solve the similarity search problem given user-defined instance-level constraints for tropical cyclone events, represented by arbitrary length multidimensional spatio-temporal data sequences. A critical component for such a problem is the similarity/metric function to compare the data sequences. We describe a novel Longest Common Subsequence (LCSS) parameter learning approach driven by nonlinear dimensionality reduction and distance metric learning. Intuitively, arbitrary length multidimensional data sequences are projected into a fixed dimensional manifold for LCSS parameter learning. Similarity search is achieved through consensus among the (similar) instance-level constraints based on ranking orders computed using the LCSS-based similarity measure. Experimental results using a combination of synthetic and real tropical cyclone event data sequences are presented to demonstrate the feasibility of our parameter learning approach and its robustness to variability in the instance constraints. We, then, use a similarity query example on real tropical cyclone event data sequences from 2000 to 2008 to discuss (i) a problem of scientific interest, and (ii) challenges and issues related to the weather event similarity search problem.

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

dimensionality reduction
metric learning
tropical cyclones
similarity search
parameter learning

atmospheric events
embedding method
ensemble method
spatio-temporal data mining
mining multi-dimensional data sequences


Low rank updated LS-SVM classifiers for fast variable selection Least squares support vector machine (LS-SVM) classifiers are a class of kernel methods whose solution follows from a set of linear equations. In this work we present low rank modifications to the LS-SVM classifiers that are useful for fast and efficient variable selection. The inclusion or removal of a candidate variable can be represented as a low rank modification to the kernel matrix (linear kernel) of the LS-SVM classifier. In this way, the LS-SVM solution can be updated rather than being recomputed, which improves the efficiency of the overall variable selection process. Relevant variables are selected according to a closed form of the leave-one-out (LOO) error estimator, which is obtained as a by-product of the low rank modifications. The proposed approach is applied to several benchmark data sets as well as two microarray data sets. When compared to other related algorithms used for variable selection, simulations applying our approach clearly show a lower computational complexity together with good stability on the generalization error. (C) 2008 Elsevier Ltd. All rights reserved.

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

low rank matrix modifications
least-squares support vector machines
leave-one-out error


The exact hypothesis test for the shape parameter of a new two-parameter distribution with the bathtub shape or increasing failure rate function under progressive censoring with random removals This study considers the exact hypothesis test for the shape parameter of a new two-parameter distribution with the shape of a bathtub or increasing failure rate function under type II progressive censoring with random removals, where the number of units removed at each failure time follows a binomial or a uniform distribution. Several test statistics are proposed and one numerical example is provided to illustrate the proposed hypothesis test for the shape parameter. Finally, a simulation study is performed to compare the power performances of all proposed test statistics. We concluded that the test statistic w1 is more attractive than other methods as it has better performance than other test statistics for most cases based on the criteria of maximum power.

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


Effective service delivery and group management in integrated terrestrial-HAP systems for multicast communications Multicast service delivery can be easily guaranteed to users in disadvantaged areas by effectively integrating HAPs (High Altitude Platforms) into the terrestrial cellular system. HAPs are meant to be as unmanned aerial vehicles, airships or aircrafts, which remain relatively stationary in the stratosphere at short distance from Earth compared to satellites. In the scientific literature, there is evidence of the effectiveness of a UMTS (Universal Mobile Telecommunications Systems) system augmented by the presence of HAPs, which are equipped with UMTS payloads and play the role of additional base stations. This integrated terrestrial-space platform intrinsically fits the exigencies of rural and emergency scenarios, which are characterized by network resource scarcity, due to either geographical reasons (such as in rural areas) or to temporary resource over-utilization/reduction (due to emergency status). In this paper, the focus is on the delivery of Multimedia Broadcast/Multicast Services (MBMS) in the reference integrated architecture. Main objectives are designing resource allocation policies to manage multicast groups between space and terrestrial coverages, and analysing their feasibility and performances in terms of offered grade of service. Copyright 2008 John Wiley & Sons, Ltd.

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

cellular systems (3g
4g)
next generation services
multicast services
radio resource management


Separation numbers of trees Let G be a graph on n vertices. Given a bijection f : V(G) -> {1, 2, ... , n}, let vertical bar f vertical bar = mini{vertical bar f(u) - f(v)vertical bar : uv is an element of E(G)}. The separation number s(G) (also known as antibandwidth [T. Calamoneri, A. Massini, L. Torok, I. Vrt'o, Antibandwidth of Complete k-ary trees, Electronic Notes in Discrete Mathematics 24 (2006), 259-266; A. Raspaud, H. Schroder, O. Sykora, L Torok, I. Vrt'o, Antibandwidth and cyclic antibandwidth of meshes and hypercubes, Discrete Mathematics 309(2009)3541-3552] of G is then max{vertical bar f vertical bar} overall such bijections f of G. We study the case when G is a forest, obtaining the following results. 1. Let F be a forest in which each component is a star. Then s(F) = n-mu/2, where mu is the minimum value of parallel to X vertical bar - vertical bar Y parallel to over all bipartitions (X, Y) of F. 2. Let d be the maximum degree of a tree T on n vertices. Then (a) s(T) >= n/2 - c(1) root nd, and (b) s(T) >= n/2 - c(2)d(2) log(d)n, where c(1) and c(2) are absolute constants. We give constructions showing that the bound (a) is asymptotically right when d is in the range n(1/3) = 4 is an absolute constant. We also show that for h >= 3 and odd d >= 3, we have s(T(h)(d)) = n/2 - Theta(d(2) + dh), where T(h)(d) is the symmetric d-ary tree of height h, improving the estimates obtained in the first of the above-mentioned references. (C) 2009 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 B 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 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 O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O


bulk loading large collections of hyperlinked resources The problem of loading large collections of hyperlinked resources into a relational database is complicated with inter-node references when these references cannot be indexed. We show that this scenario can arise in many real life hyperlinked resources and propose several solutions to address the problem. We run some experiments over a graph of the Web with 178 million nodes and around 1 billion edges and report our results.

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


Broadband scalable model for Si-RF on-chip spiral inductors with substrate eddy current effect A new broadband scalable compact model for on-chip spiral inductor is presented. It includes a substrate network and a high resistive component to accurately capture the substrate eddy current effect, skin and proximity effects at high frequencies. The proposed model shows a good match with the measurement results over a frequency range of up to 20 GHz. An automated parameter extraction and optimization procedure has been developed using equivalent circuit analysis and particle swarm optimization. We achieved good scalability for all model parameters with respect to spiral layout geometry. (c) 2007 Wiley Periodicals, Inc.

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

spiral inductor
parameter extraction
particle swarm optimization
eddy current effect


algorithms for facility location problems with outliers Facility location problems are traditionally investigated with the assumption that all the clients are to be provided service. A significant shortcoming of this formulation is that a few very distant clients, called outliers , can exert a disproportionately strong influence over the final solution. In this paper we explore a generalization of various facility location problems ( K -center, K -median, uncapacitated facility location etc) to the case when only a specified fraction of the customers are to be served. What makes the problems harder is that we have to also select the subset that should get service. We provide generalizations of various approximation algorithms to deal with this added constraint.

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

select
approximation algorithms
facility location
influence
outliers
case
paper
constraint

locatability custom general algorithm exploration


The maximum factor queue length batching scheme for video-on-demand systems In a video-on-demand environment, batching of video requests is often used to reduce I/O demand and improve throughput. Since viewers may defect if they experience long waits, a good video scheduling policy needs to consider not only the batch size but also the viewer defection probabilities and wait times. Two conventional scheduling policies for hatching are the first-come-first-served (FCFS) policy, which schedules the video with the longest waiting request. and the maximum queue length (MQL) policy, which selects the video with the maximum number of waiting requests. Neither of these policies leads to entirely satisfactory results. MQL tends to be too aggressive in scheduling popular videos by considering only the queue length to maximize batch size, while FCFS has the opposite effect by completely ignoring the queue length and focusing on arrival time to reduce defections. In this paper, we introduce the notion of factored queue length and propose a hatching policy that schedules the video with the maximum factored queue length. We refer to this as the MFQL policy. The factored queue length is obtained by weighting each video queue length with a factor which is biased against the more popular videos. An optimization problem is formulated to solve for the best weighting factors for the various videos. We also consider MFQL implementation issues. A simulation is developed to compare the proposed MFQL variants with FCFS and MQL. Our study shows that MFQL yields excellent empirical results in terms of standard performance measures such as average latency time, defection rates, and fairness.

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

video-on-demand
scheduling algorithms
batching schemes


Multiple-description iterative coding image watermarking To embed the multiple watermarks is a way to increase robustness in image watermark. The limitation of embedding multiple watermarks is that the limited capacity of an image severely limits the size of the watermark. Multiple-description coding is a good candidate to solve this limitation by trading off between transmission bandwidth and bit error rate. Traditionally, multiple-description coding is considered in onoff channels where channels are not marred by bit errors but occasional connection outages such as dropped packets. To apply multiple-description coding in image watermarking, we need a form of multiple-description coding for noisy channels instead of onoff channels. In this paper, we propose to add iterative coding in multiple description in order to combat bit errors in image watermarking. We call this method multiple-description iterative coding (MDIC) image watermarking. We tested our system on six images. On average, bit error did not happen until we compressed the image in JPEG to PSNR 36.97 dB. We concluded that MDIC was a very good way to increase robustness for image watermarking.

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


A non-Abelian analogue of Whitneys 2-isomorphism theorem We give a non-Abelian analogue of Whitneys 2-isomorphism theorem for graphs. Whitneys theorem states that the cycle space determines a graph up to 2-isomorphism. Instead of considering the cycle space of a graph which is an Abelian object, we consider a mildly non-Abelian object, the 2-truncation of the group algebra of the fundamental group of the graph considered as a subalgebra of the 2-truncation of the group algebra of the free group on the edges. The analogue of Whitneys theorem is that this is a complete invariant of 2-edge connected graphs: let G, G? be 2-edge connected finite graphs; if there is a bijective correspondence between the edges of G and G? that induces equality on the 2-truncations of the group algebras of the fundamental groups, then G and G? are isomorphic.

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

graph theory
whitneys 2-isomorphism theorem


Real-Time Freight Train Driver Rescheduling during Disruption Railway operators adjust timetables, and accordingly reschedule rolling stock circulation and crew duties, when the train operations are disrupted by accidents or adverse weather conditions. This paper discusses the problem of rescheduling driver assignment to freight trains after timetable adjustment has been completed. We construct a network from the disrupted situation, and model the problem as an integer programming problem with set-covering constraints combined with set-partitioning constraints. The integer program is solved by column generation in which we reduce the column generation subproblem to a shortest path problem and such paths by utilizing data parallelism. Numerical experiments using a real timetable, driver scheduling plan and major disruption data in the highest-frequency freight train operation area in Japan reveal that our method provides a quality driver rescheduling solution within 25 seconds.

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

driver rescheduling problem
set-covering problem


Optimization of Intelligent Approach for Low-Cost INS/GPS Navigation System Due to the inherent highly nonlinear vehicle state error dynamics obtained from low-cost inertial navigation system (INS) and Global Positioning System (GPS) along with the unknown statistical properties of these sensors, the optimality/accuracy of the classical Kalman filter for sensor fusion is not guaranteed. Therefore, in this paper, low-cost INS/GPS measurement integration is optimized based on different artificial intelligence (AI) techniques: Neural Networks (NN) and Adaptive Neuro-Fuzzy Inference System (ANFIS) architectures. The proposed approaches are aimed at achieving high-accuracy vehicle state estimates. The architectures utilize overlapping windows for delayed input signals. Both the NN approaches and the ANFIS approaches are used once with overlapping position windows as the input and once with overlapping position and velocity windows as the input. Experimental tests are conducted to evaluate the performance of the proposed AI approaches. The achieved accuracy is presented and discussed. The study finds that using ANFIS, with both position and velocity as input, provides the best estimates of position and velocity in the navigation system. Therefore, the dynamic input delayed ANFIS approach is further analyzed at the end of the paper. The effect of the input window size on the accuracy of state estimation is also discussed.

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

adaptive neuro-fuzzy inference system (anfis)


HARPOON: An Obfuscation-Based SoC Design Methodology for Hardware Protection Hardware intellectual-property (IP) cores have emerged as an integral part of modern system-on-chip (SoC) designs. However, IP vendors are facing major challenges to protect hardware IPs from IP piracy. This paper proposes a novel design methodology for hardware IP protection using netlist-level obfuscation. The proposed methodology can be integrated in the SoC design and manufacturing flow to simultaneously obfuscate and authenticate the design. Simulation results for a set of ISCAS-89 benchmark circuits and the advanced-encryption-standard IP core show that high levels of security can be achieved at less than 5% area and power overhead under delay constraint.

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

design for security
hardware authentication
hardware obfuscation
intellectual-property (ip) piracy


Looking Forward 10 Years to Multimedia Successes A panel at ACM Multimedia 2012 addressed research successes in the past 20 years. While the panel focused on the past, this article discusses successes since the ACM SIGMM 2003 Retreat and suggests research directions in the next ten years. While significant progress has been made, more research is required to allow multimedia to impact our everyday computing environment. The importance of hardware changes on future research directions is discussed. We believe ubiquitous computing-meaning abundant computation and network bandwidth-should be applied in novel ways to solve multimedia grand challenges and continue the IT revolution of the past century.

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

management
algorithms
human factors
performance
multimedia research directions


Neural networks applications in concrete structures This paper presents and discusses the applications of neural networks in concrete structures. It aims at introducing neural networks applications in structural design. The paper covers two applications of neural networks in concrete structures. Backpropagation networks are chosen for the proposed network, which is written using the programming package MAT-LAB. The overall results are compared and observed for the performance of the networks. Based on the applications it was found that neural networks are comparatively effective for a number of reasons, which include the amount of CPU memory consumed by neural networks is less than that consumed by conventional methods and their ease of use and implementation, neural networks provide both the users and the developers more flexibility to cope with different kinds of problems.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O 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
optimisation
concrete design


Modeling in multi-resolution and its applications it is becoming common for many designers to work together on very complex assemblies in a collaborative environment. To work efficiently in this environment, the capabilities to simplify the portions of an assembly and to reset it to the original resolution should be added to the current CAD systems. Thus operators realizing multi-resolution on B-rep were proposed in previous work. This paper illustrates a prototype multi-resolution system to integrate the proposed operators and its applications. The multi-resolution system can be used in similarity comparisons to reduce the calculation load and to get the full comparison result in the overall shape. Then the features recognized with this system can be used in more detailed comparisons. This system also can be used conceptually to solve security problems in collaborative design.

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

level of detail
multi-resolution
similarity comparison


Kernel bounds for disjoint cycles and disjoint paths In this paper, we show that the problems DISJOINT CYCLES and DISJOINT PATHS do not have polynomial kernels, unless NP subset of coNP/poly. Thus, these problems do not allow polynomial time preprocessing that results in instances whose size is bounded by a polynomial in the parameter at hand. We build upon recent results by Bodlaender et al. [6] and Fortnow and Santhanam [20], that show that NP-complete problems that are 'or-compositional' do not have polynomial kernels, unless NP subset of coNP/poly. To this machinery, we add a notion of transformation, and obtain that DISJOINT CYCLES, and DISJOINT PATHS do not have polynomial kernels, unless NP subset of coNP/poly. For the proof, we introduce a problem on strings, called DISJOINT FACTORS, and first show that this problem has no polynomial kernel unless NP subset of coNP/poly. We also show that the related DISJOINT CYCLES PACKING problem has a kernel of size O(k log k). (C) 2011 Elsevier B.V. All rights reserved.

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

data reduction
kernelization
fixed parameter complexity
algorithms
lower bounds


Face clustering of a large-scale CAD model for surface mesh generation A detailed CAD model needs manual clean-up, or simplifying operations, before a finite element mesh can be automatically generated because such a model consists of hundreds or thousands of faces many of which may be smaller than a desired mesh element size. We propose an automated face clustering method used as a pre-process of surface mesh generation. By decomposing a model into face clusters so that each region can be projected onto a simple parametric surface such as a plane, we obtain a final mesh as an aggregate of sub-meshes for respective clusters without time-consuming manual preparation work. The projection onto a surface realises re-parameterisation as well as suppression of small details. The main contribution of this work is the integration of (1) a greedy algorithm for combining faces into clusters, and (2) geometric indices that reflect various aspects of a preferable shape for a cluster. The validity of the approach is demonstrated with results of clustering and mesh generation for a realistic-scale CAD model.

B I 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 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 B I O O O O O

mesh simplification
re-parameterisation
finite element analysis


Distributed oblivious function evaluation and its applications This paper is about distributed oblivious function evaluation (DOFE). In this setting one party (Alice) has a function f (x), and the other party (Bob) with an input alpha wants to learn f (alpha) in an oblivious way with the help of a set of servers. What Alice should do is to share her secret function f (x) among the servers. Bob obtains what he should get by interacting with the servers. This paper proposes the model and security requirements for DOFE and analyzes three distributed oblivious polynomial evaluation protocols presented in the paper.

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

oblivious function evaluation
oblivious polynomial evaluation
distributed

secure multiparty computation
information security


A NEW APPROACH TO THE AUTOMATIC WEB ACCESSIBILITY The number of Web pages created in an inaccessible manner is very high, and to convert them to be accessible can be impossible. We present a study of different tools that can help to obtain a total Web Accessibility. With this study, we can see the advantages of the automatic correction and the possibilities that this kind of tools offer. The result of the study shows how the applications adapt the Web pages to both the World Wide Web Consortium HTML grammar and to the Web Content Accessibility Guidelines. With this study we find an automatic way to improve Web Accessibility and to solve the problems that it can offer to the Web pages authors. This way consists of combining two tools, This combination gives us results that allow disabled people to use a system that can convert the entire Web in an accessible way.

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

web accessibility
world wide web consortium
html


Multi-objective scheduling of dynamic job shop using variable neighborhood search Dynamic job shop scheduling that considers random job arrivals and machine breakdowns is studied in this paper. Considering an event driven policy rescheduling, is triggered in response to dynamic events by variable neighborhood search (VNS). A trained artificial neural network (ANN) updates parameters of VNS at any rescheduling point. Also, a multi-objective performance measure is applied as objective function that consists of makespan and tardiness. The proposed method is compared with some common dispatching rules that have widely used in the literature for dynamic job shop scheduling problem. Results illustrate the high effectiveness and efficiency of the proposed method in a variety of shop floor conditions.

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

dynamic job shop
variable neighborhood search

multi-objective scheduling
artificial neural networks


a comprehensive approach to parallel data flow analysis We present a comprehensive approach to performing data flow analysis in parallel. We first identify three types of parallelism inherent in the data flow solution process: independent-problem parallelism, separate-unit parallelism and algorithmic parallelism. We then describe a unified framework to exploit them. Our investigations of typical Fortran programs reveal an abundance of the last two types of parallelism. In particular, we illustrate the exploitation of algorithmic parallelism in the design of our parallel hybrid data flow analysis algorithm and report on its empirical performance.

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

parallel data flow analysis
data flow analysis


safely selecting subsets of training data Highly versatile classifiers for document analysis systems demand representative training sets which can be dauntingly large, often challenging conventional trainable classifier technologies. We propose to select a small subset of training data, matched to each particular test set, in hopes of improved speed without loss of accuracy. Since selection must occur on line, we cannot use classifiers that require off-line training. Fortunately, Nearest Neighbors classifiers support on-line training; we use a fast approximate kNN technology using hashed k-D trees. The distribution of samples in k-D bins can be used to measure similarity between any two document images: we select the three most similar training images for any given test image. In experiments on a document image content extraction system, our algorithm was able to prune 118 training images to three, for a speedup of a factor of 17 with no loss of accuracy. Other experiments with an oracle and manual selection suggest that it may be possible to improve accuracy as well.

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 O O O O O O O O O O O

document content extraction
k nearest neighbors
adaptive recognition
isogeny
decimation
algorithms


extensions to and optimization of a mobile computational system for internet programming Mobile computations are powerful tools that can enable efficient, reliable, and secure utilization of idle resources on large networks like the Internet. Native support for strongly mobile computations is an essential prerequisite for a user-friendly Internet programming language. In this work, we discuss further extensions and optimizations to our prototype Mobile Computational Model [7] that will take us a step further towards a full-fledged working system. Each of the tasks undertaken is non-trivial since it is complicated by considerations of strong mobility, heterogeneous architectures, and networks, within the constraints of the need for increased security and reliability.

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 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

communication
code optimization
mobile computation
arrays


Nonlinear Predictor-Based Dynamic Resource Allocation Over Point-to-Multipoint (P2MP) Networks: A Control Theoretical Approach Most broadband access networks such as passive optical networks (PONs) adopt the point-to-multipoint (P2MP) topology. One critical issue in such networks is the upstream resource management and allocation mechanism. Nonlinear predictor-based dynamic resource allocation (NLPDRA) schemes for improving the P2MP network upstream transmission efficiency have been investigated in an ad hoc manner. In this paper, we establish a general state space model to analyze the controllability and stability of the NLPDRA schemes from the P2MP network system's point of view and propose controller design guidelines to maintain the system stability under different scenarios. Analytical results show that NLPDRA maintains the P2MP network system controllability even when the loaded network traffic changes drastically. We further prove that a P2MP network system with NLPDRA is stable by proper pole placements as the traffic changes. Finally, we provide guidelines to design a optimal compensator to achieve system accuracy.

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

upstream resource management
state space
controllability
stability
controller design

nonlinear prediction-based dynamic resource allocation (nlpdra)


Students' perceptions of ICT-related support in teaching placements Abstract Recent research has shown that students' use of information and communications technology (ICT) on teaching practice is necessary for effective future use of ICT in the classroom. However, this paper reports that there are a number of factors affecting the use of ICT by student-teachers in their school placements. All 110 student-teachers attending one university's eight Postgraduate Certificate in Education (PGCE) courses completed a questionnaire on their attitudes to ICT in learning and teaching and their initial experiences of the application of ICT in schools. In-depth interviews with the student-teachers, as well as univer-sity tutors and teachers, revealed a range of issues that reflected how student-teachers perceive their school-based ICT training and what they think could improve their experiences. Recommendations are offered for the improvement of the ICT school experiences for student-teachers until teacher training is completed and improved ICT infrastructure is in place in schools. The overriding conclusion is that schools must be supported and resourced properly, and teachers must have effective ICT training, before improvements in school-based ICT development for student-teachers can be achieved.

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

attitude
case study
computers
illuminative
it-use
post-graduate


a verification technique for hardware designs Most existing hardware design verification techniques (logic simulation, symbolic simulation etc.), as well as the design phase, are rather synthetic. This paper discusses an analytic verification technique with examples of its application. This technique employs backward symbolic simuation, or causality tracing, which is carried out from the negation of a proposition which should be verified. Analyticity this technique has, not only makes verification powerful but gives it another feature, design error diagnosis.

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

verification causality diagnosis logic hardware examples paper simulation feature design


Uniformly inserting points on square grid We consider the problem of inserting points in a square grid, which has many motivations, including halftoning in reprography and image processing. The points are inserted one at a time. The objective is to distribute the points as uniformly as possible. More specifically, after each insertion, the gap ratio should be as small as possible. We give an insertion strategy with a maximal gap ratio no more than 2 root 2 approximate to 2.828, which is the first result in uniformly inserting points in a grid. Moreover, we show that no online algorithm can achieve the maximal gap ratio strictly less than 2.5 for a 3 x 3 grid. (C) 2011 Elsevier B.V. All rights reserved.

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

algorithms
computational geometry
point insertion
uniformity


Monitoring and steering Grid applications with GRID superscalar We present the design and implementation of a general task monitoring and steering system for Grid applications (GSTAT). The system is integrated in the GRID superscalar (GRIDSs) programming framework. Information at the application, Grid node, and individual task levels are supplied upon request. Using the steering capabilities, individual tasks or the whole application can be cancelled. The corresponding jobs can be restarted using fault tolerance and checkpointing capabilities based on GRIDSs. In addition, the computational resources assigned to an application can be modified. GSTAT is tested using high throughput and high performance computing cases on an Internet-based Grid of computers.

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 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

grid superscalar
steering grid applications

grid computing
monitoring grid applications


Effects of Duration and Laughter on Subjective Happiness Within Different Modes ofCommunication Media naturalness theory and social information processing theory make competing predictions regarding the effectiveness of different modes of communication at creating and maintaining emotionally intense social relationships. We explored how the duration of interaction and the form of laughter influenced happiness in communication modes with different levels of media naturalness. Forty-one participants completed a 14-day contact diary, recording interactions across face-to-face, Skype, telephone, instant messaging, texting, and e-mail/social network sites. Increases in duration of interaction positively predicted happiness only for face-to-face interactions, offering partial support for the media naturalness hypothesis. Laughter positively predicted happiness in all but one of the communication modes, with real and symbolic laughter having similar effects, a result consistent with the social information processing theory.

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

social relationships
happiness
laughter
media naturalness theory
social information processing theory

face-to-face interaction
computer-mediated communication


Efficient Computation of Sparse Hessians Using Coloring and Automatic Differentiation The computation of a sparse Hessian matrix H using automatic differentiation (AD) can be made efficient using the following four-step procedure: (1) Determine the sparsity structure of H, (2) obtain a seed matrix S that defines a column partition of H using a specialized coloring on the adjacency graph of H, (3) compute the compressed Hessian matrix B equivalent to HS, and (4) recover the numerical values of the entries of H from B. The coloring variant used in the second step depends on whether the recovery in the fourth step is direct or indirect: a direct method uses star coloring and an indirect method uses acyclic coloring. In an earlier work, we had designed and implemented effective heuristic algorithms for these two NP-hard coloring problems. Recently, we integrated part of the developed software with the AD tool ADOL-C, which has recently acquired a sparsity detection capability. In this paper, we provide a detailed description and analysis of the recovery algorithms and experimentally demonstrate the efficacy of the coloring techniques in the overall process of computing the Hessian of a given function using ADOL-C as an example of an AD tool. We also present new analytical results on star and acyclic coloring of chordal graphs. The experimental results show that sparsity exploitation via coloring yields enormous savings in runtime and makes the computation of Hessians of very large size feasible. The results also show that evaluating a Hessian via an indirect method is often faster than a direct evaluation. This speedup is achieved without compromising numerical accuracy.

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

acyclic coloring
star coloring
automatic differentiation

sparse hessian computation
combinatorial scientific computing


Interplay of cost and adoption of tele-medicine in Sub-Saharan Africa: The case of tele-cardiology in Ethiopia ...the barriers to diffusion of Tele-Medicine are not entirely technical. Cost has to simultaneously satisfy a number of stakeholders... (Anderson, Aydin and Jay, et al., 1994). Rising costs of the provision of healthcare have been a major issue for debate in both developing and developed countries. This is especially true of very capitalistic societies such as the United States where privatization of the healthcare sector has left many with little or no affordable healthcare. The situation is even worse in developing economies. Developing countries deal with various problems in the provision of health services and healthcare Tan et al. (E-medicine diffusion: E-medicine in Developed and Developing countries. Chapter 8 in E-health paradigm shift: Perspectives, domains and challenges. In Tan J. (Ed.), Imprint of Wiley, New York, Jossey-Bass, 2005). Some of these problems include acute shortages of healthcare professionals and medical facilities Mbarika et al. (Journal of the Association for Information Systems (JAIS) 2005;6(5):130-170). Such shortages have resulted in growing numbers of middle to upper-class citizens of developing countries traveling abroad to seek necessary health services. Using a multi-method case study research, this paper examines the role of Tele-Medicine in the healthcare system and analyzes the costs and benefits of introducing Tele-Cardiology services in Ethiopia (a Sub-Saharan African country). This is a cost comparison study for the treatment of cardiac patients traveling abroad versus patients treated via Tele-Cardiology. Our findings show that Tele-Cardiology is clinically more feasible and more cost effective compared to patients traveling abroad for treatment.

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

tele-medicine
cost effectiveness
cardiology
patient travel
telecommunication


On maximizing clique, clique-Helly and hereditary clique-Helly induced subgraphs ? Clique-Helly and hereditary clique-Helly graphs are polynomial-time recognizable. Recently, we presented a proof that the clique graph recognition problem is NP-complete [L. Alcn, L. Faria, C.M.H. de Figueiredo, M. Gutierrez, Clique graph recognition is NP-complete, in: Proc. WG 2006, in: Lecture Notes in Comput. Sci., vol. 4271, Springer, 2006, pp. 269277]. In this work, we consider the decision problems: given a graph G=(V,E) G = ( V , E ) and an integer k?0 k ? 0 , we ask whether there exists a subset V??V V ? ? V with |V?|?k | V ? | ? k such that the induced subgraph G[V?] G [ V ? ] of G G is, variously, a clique, clique-Helly or hereditary clique-Helly graph. The first problem is clearly NP-complete, from the above reference; we prove that the other two decision problems mentioned are NP-complete, even for maximum degree 6 planar graphs. We consider the corresponding maximization problems of finding a maximum induced subgraph that is, respectively, clique, clique-Helly or hereditary clique-Helly. We show that these problems are Max SNP-hard, even for maximum degree 6 graphs. We show a general polynomial-time 1 ? + 1 -approximation algorithm for these problems when restricted to graphs with fixed maximum degree ? ? . We generalize these results to other graph classes. We exhibit a polynomial 6-approximation algorithm to minimize the number of vertices to be removed in order to obtain a hereditary clique-Helly subgraph.

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

clique graphs
clique-helly graphs
hereditary clique-helly graphs
np-complete
max snp-hard
approximation algorithms


Approximate Bayesian estimation of a 3D point pattern from multiple views A Bayesian method is suggested for combining multiple views of different observation accuracies to reconstruct a 3D point pattern, using a Wishart distribution as prior distribution to model varying measurement error variances and covariances. Experiments are performed on synthetic data simulating reconstruction of tree positions from aerial photography and on real data of this type.

O O O O O O O O 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

heteroscedastic displacement errors
bayes estimation
conjugate prior distributions
posterior mode
individual tree positions


An incrementally deployable approach for achieving fair rate allocations Several router mechanisms have been proposed to achieve fair rate allocations. However, most of them require the proposed mechanisms to be deployed at all routers within an autonomous domain in order to achieve the desired, or any appreciably improved, quality of service. In this paper, we present an incrementally deployable QoS architecture called iQ. iQ consists of a set of core- and edge-router mechanisms that allow for changing one router at a time, improving the rate fairness provided by the network gracefully, for each additional iQ router deployed. We use simulations to compare the incremental deployability of the iQ architecture with that of existing approaches.

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

network quality of service
core-stateless qos


user experience evaluation in the wild This article details experience feedback resulting from a user experience study in the wild (i.e. in-situ). The system under test was a mobile device for skiers, which aimed at improving their users' experience. The skiers were equipped with a mini-camera, an accelerometer and a geo-localization system. Thanks to a smartphone, they could replay, on trails, theirs best performances (video, maximum speed, ...). The article focuses both on the methodological and the technological issues encountered during these experimentations, and proposes recommendations.

B I 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

user tests
mobile devices
in-situ evaluation


Task artifacts and strategic adaptation in the change signal task The change signal task is a variant of a two-alternative forced-choice (2AFC) task where the initial stimulus is superseded with the alternative stimulus (the change signal) at a delay on a proportion of trials. Taking advantage of the overlap in task requirements, we present a single model that can perform both tasks, and we validate the model using the empirical data from participants who performed them sequentially. The results confirmed the existence of a dynamic hedging strategy in the change signal task, and provided evidence against a role for cognitive fatigue in producing the slower response times with increased time on task. When fitting the 2AFC task, the model required adjustment to one architectural parameter while the rest were left to defaults. That parameter was then constrained while fitting the remaining three task-specific parameters for the change signal task. This effectively reduced a degree of freedom in the model fitting process, and increased confidence in the model as it closely matched human performance in multiple tasks.

O O O O O O 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 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 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 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

act-r
two-alternative forced-choice
cognitive model