The formability of aluminum foam sandwich panels The present paper aims to study the formability of Aluminum Foam Sandwich (AFS) panels. At now, the final shape of foamed devices is directly obtained through the foaming process itself and no further shaping steps are expected. In any case, further manufacturing processes may be exploited to produce more complex parts. Among forming operations, bending can be regarded as one of the simplest processes for both study and application. Besides, bending tests may yield interesting information about material properties. With regard to the metal foams characterization, several bending tests on AFS panels fabricated by Alulight were carried out by varying the process conditions. A universal testing machine was employed for this purpose, collecting data about the deformed geometry and about load vs. displacement. Even though the samples deformation was related to the occurrence of foam cells failure or collapse, once the process was terminated, they still retained a significant bending strength. The metal foams properties were also investigated using both non-destructive and mechanical tests. In particular, thickness measurements (using an ultrasonic feeler), X-ray analysis and foam density measurements were carried out on AFS specimens before the execution of both upsetting and bending tests. Finite Element simulations of the foam bending process were performed to investigate stress and strain distributions on the specimens. In particular, an isothermal plane strain model of the bending process was setup using the FEM commercial code Deform 2D. The results of this study were used to produce closed structure components (square shapes) by combining three 90 bends. A further improvement consisted in joining the open ends, to enhance shear and torsion resistance. Among joining techniques conventional welding processes (Tungsten Inert GasTIG and laser) and a non-conventional method (Friction Stir WeldingFSW) were investigated. Finally, the mechanical properties of the joints were characterized using both three and four point bending tests.

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


Finite Burn Maneuver Modeling for a Generalized Spacecraft Trajectory Design and Optimization System The modeling, design, and optimization of finite burn maneuvers for a generalized trajectory design and optimization system is presented. A generalized trajectory design and optimization system is a system that uses a single unified framework that facilitates the modeling and optimization of complex spacecraft trajectories that may operate in complex gravitational force fields, use multiple propulsion systems, and involve multiple spacecraft. The modeling and optimization issues associated with the use of controlled engine burn maneuvers of finite thrust magnitude and duration are presented in the context of designing and optimizing a wide class of finite thrust trajectories. Optimal control theory is used examine the optimization of these maneuvers in arbitrary force fields that are generally position, velocity, mass, and are time dependent. The associated numerical methods used to obtain these solutions involve either, the solution to a system of nonlinear equations, an explicit parameter optimization method, or a hybrid parameter optimization that combines certain aspects of both. The theoretical and numerical methods presented here have been implemented in copernicus, a prototype trajectory design and optimization system under development at the University of Texas at Austin.

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

trajectory optimization
spacecraft trajectory optimization
primer vector theory


Single activity sensor-based ensemble analysis for health monitoring of solitary elderly people Public health monitoring for solitary elderly people must be implemented in a particularly economic way because of their low-income status. The aim of this paper is to propose a model-based method combined with conventional reasoning methods such as multiple regression and the boosting strategy. The role of model-based reasoning is to generate secondary situational information from activity data gathered at home. Current health condition information is then provided as part of an activity-based smart management system for health monitoring. Only one activity sensor per house is considered. In this paper, we also discuss how the Korean government has actually applied this method in smart-care services for more than ten thousand solitary elderly people. The experiments are conducted based on the u-care system, which is composed of an activity sensor connected to a remote server using a wireless sensor network. The remote server includes multi-agents which analyze and diagnose current health conditions. (C) 2011 Elsevier Ltd. All rights reserved.

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

activity context
model-based reasoning
remote health monitoring


Planar High Gain Dielectric Loaded Exponentially Tapered Slot Antenna for Millimeter Wave Wireless Communications A new and upcoming application is the use of millimeter wave (MmW) antennas for high date rate point-to-point connections to serve gigabit (Gi-Fi) wireless communications. The concept of substrate integrated waveguide (SIW) and exponentially tapered slot (ETS) antenna are used together design a high gain, efficient planar dielectric loaded antenna for MmW Gi-Fi wireless communications at 60GHz. The SIW is used to feed the antenna and a dielectric loading is utilized in front of the antenna to increase the gain. The dielectric loaded ETS antenna and compact SIW feed are fabricated on a single substrate, resulting in low cost and easy fabrication. The antenna with elliptical shaped dielectric loaded is fabricated using printed circuit board process. The measured gain of the antenna is 11.4dB, while the radiation efficiency of 96.84% is obtained at 60GHz. The measurement results are compared with simulated results.

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 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 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 B O O O O O O O O

exponentially tapered slot antenna
dielectric loading
substrate integrated waveguide
60ghz


High-speed CMOS unity-gain current amplifier A high-performance CMOS unity-gain current amplifier is proposed. The solution adopts two feedback loops to reduce the input resistance and a nested-Miller technique to provide frequency compensation. A design example using a 0.8?m process and a 2V supply is given and SPICE simulations show a bandwidth of 75MHz, no slew-rate limitations and a settling time better than 50ns, irrespective of the current amplitude. Input and output resistances are better than 0.1? and 15M?, respectively. The input-referred white noise spectral density is 10 pA / Hz .

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

current follower
unity-gain amplifier
current mode


Heuristics for urban road network design: Lane layout and signal settings This paper concerns the urban road network design problem. In urban areas supply has usually been unable to keep pace with increasing demand: the only possibility is often to reorganise the current supply configuration in order to use existing resources efficiently. Thus, in urban areas signal settings and network topology (in particular lane layout) are the two major factors that can be handled by design models. Methods for the combined design of signal settings and topology are proposed in this paper. All the methods proceed in two stages: the first deals with integer variables (topology), while the second deals with continuous variables (signal settings). Some metaheuristics (Hill Climbing, Simulated Annealing, Tabu Search, Genetic Algorithms and Path Relinking) are specified for the topology design stage, and they are used singularly or jointly. The continuous part of the solution, with fixed topology is optimized through an algorithm for asymmetrical deterministic equilibrium assignment. This paper focuses on evaluating performances obtained by all the different algorithms proposed for the topology design stage. The algorithms are compared by applications to real networks, and some conclusions are drawn about their efficiency.

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 O O O O O O

transportation
traffic
network flows
combinatorial optimization


Tangible authoring of 3D virtual scenes in dynamic augmented reality environment This paper proposes tangible interfaces and interactions for authoring 3D virtual and immersive scenes easily and intuitively in tangible augmented reality (AR) environment. It provides tangible interfaces for manipulating virtual objects in a natural and intuitive manner and supports adaptive and accurate vision-based tracking in AR environments. In particular, RFID is used to directly integrate physical objects with virtual objects and to systematically support the tangible query of the relation between physical objects and virtual ones, which can provide more intuitive tangibility and a new way of virtual object manipulation. Moreover, the proposed approach offers an easy and intuitive switching mechanism between tangible environment and virtual environment. This paper also proposes a context-adaptive marker tracking method which can remove an inconsistent problem while embedding virtual objects into physical ones in tangible AR environments. The context-adaptive tracking method not only adjusts the locations of invisible markers by interpolating the locations of existing reference markers and those of previous ones, but also removes a jumping effect of movable virtual objects when their references are changed from one marker to another. Several case studies for generating tangible virtual scenes and comparison with previous work are given to show the effectiveness and novelty of the proposed approach. (C) 2010 Elsevier B.V. All rights reserved.

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

tangible interface
virtual studio
virtual reality


Design of QoS and admission control for VoIP services over IEEE 802.11e WLANs Supporting telephone services using wireless LAN as the access network is an important application nowadays. The SIP and IEEE 802.11e are the two most promising protocols to support such services. In this paper, we show how to integrate SIP and 802.11e to conduct call admission control and resource reservation to support VoIP's QoS in IEEE 802.11e WLANs. Besides, we also suggest some adjustments and MAC enhancements to 802.11e to facilitate VoIP traffics over WLANs.

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

ieee 802.11 e
quality of service (qos)
voice over ip (voip)
wireless network


A neurocomputing model to calculate the thermo-solutal diffusion in liquid hydrocarbon mixtures A thermodiffusion model based on the principles of artificial neural networks has been proposed. In addition to the development and validation with respect to the experimental data of binary n-alkane mixtures from the literature, the ability of the model to predict the known thermodiffusion trends has been presented. Comparison with other models in the literature is made to establish the superiority of the method. The model can be easily extended to multi-component mixtures and has potential to be applicable to study thermodiffusion in a wide variety of mixtures, viz., polymers, water-alcohol, colloidal mixtures, etc.

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

thermodiffusion
liquid hydrocarbon mixtures
artificial neural networks


Evaluation of a visual layering methodology for colour coding control room displays Eighteen people participated in an experiment in which they were asked to search for targets on control room like displays which had been produced using three different coding methods. The monochrome coding method displayed the information in black and white only, the maximally discriminable method contained colours chosen for their high perceptual discriminability, the visual layers method contained colours developed from psychological and cartographic principles which grouped information into a perceptual hierarchy. The visual layers method produced significantly faster search times than the other two coding methods which did not differ significantly from each other. Search time also differed significantly for presentation order and for the method order interaction. There was no significant difference between the methods in the number of errors made. Participants clearly preferred the visual layers coding method. Proposals are made for the design of experiments to further test and develop the visual layers colour coding methodology.

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

colour displays
cartography
control rooms
perception


Energy-Aware task scheduler for self-powered sensor nodes: From model to firmware The self-powering paradigm surely represents a challenging issue in the Wireless Sensor Network (WSN) field. The chance of supplying the sensor node with environmental energy is attractive not only to make it autonomous and reduce the human intervention for battery substitution but also to improve the overall WSN flexibility and applicability. From this same perspective, a relevant role is played by the node task scheduling, which is required to face strong constraints due to energy availability limitations. On purpose, some of the authors have recently proposed an Energy-Aware approach (namely Energy-Aware Lazy Scheduling Algorithm, EA-LSA), which shows a certain versatility in efficiently exploiting the harvested energy, reducing the starving occurrences in non-ideal conditions, with respect to the no-EA counterpart. In this work a task scheduler based on the EA-LSA technique has been implemented on a low-cost and commercially available platform, from Texas Instruments, with the aim to propose an open and easy-to-use HW/SW reference for the community working in the field. The firmware, including the hardware abstraction and the scheduling routine layers, has been developed from scratch. Moreover, a few tasks have been developed so that the device activity could be simulated in a realistic scenario. To monitor the harvesting process an emulated energy harvester has been devised and included in the overall framework. The different task energy consumptions have been measured by means of an energy audit tool, specifically set up in order to properly gauge the very low current consumptions of the device. Experiments performed under different power income levels, allowed to positively conclude about the effectiveness of the implemented Energy-Aware scheduler, its flexibility in terms of environmental energy exploitation, and therefore its suitability for involvement in real-world WSNs.

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

energy-aware task scheduler
self-powered sensor nodes
energy harvesting
wireless sensor networks
embedded systems


A robust hashing algorithm based on SURF for video copy detection To protect digital video from unauthorized use, video copy detection is an active research topic in the field of copyright control. For content-based copy detection, the key issue is to extract robust transformation-invariant feature. In this paper, a robust hashing algorithm based on speeded up robust feature (SURF) and ordinal measure (OM) is proposed for video copy detection. Since SURF is an invariant feature based on scale space theory, the local feature is extracted by SURF in a frame-by-frame manner. Every frame is divided into 44 blocks, and every block is traversed by Hilbert-order rasterization to count the number of SURF points. The Hash value is built by the difference of SURF points between adjacent blocks in Hilbert curve. Moreover, two special copy attacks, i.e., picture-in-picture and video flipping, are specifically discussed. Experimental results show the effectiveness of the proposed approach in both accuracy and efficiency.

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

content-based copy detection
video hashing
hilbert curve order


teaching theory of computation using pen-based computers and an electronic whiteboard This paper describes a Theory of Computation course that was taught in an electronic classroom equipped with a network of pen-based computers, a touch-sensitive electronic whiteboard, and locally written groupware that was designed to enhance the ability of teachers and students to share written information during class. We first describe the technology that was used to support the course, and then provide an overview of the instructor's use of this technology to engage students during class. Finally, we present the students' reaction to the approach.

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

network use computation teaching theory support paper groupware class

sharing sensitive technologies pen touch informal student


Using hippocampal-striatal loops for spatial navigation and goal-directed decision-making The hippocampus plays a central role in spatial representation, declarative and episodic memory. In this area, so-called place cells possess high spatial selectivity, firing preferentially when the individual is within a small area of the environment. Interestingly, it has been found in rats that these cells can be active also when the animal is outside the location or context of their corresponding place field producing so-called forward sweeps. These typically occur at decision points during task execution and seem to be utilized, among other things, for the evaluation of potential alternative paths. Anticipatory firing is also found in the ventral striatum, a brain area that is strongly interconnected with the hippocampus and is known to encode value and reward. In this paper, we describe a biologically based computational model of the hippocampal-ventral striatum circuit that implements a goal-directed mechanism of choice, with the hippocampus primarily involved in the mental simulation of possible navigation paths and the ventral striatum involved in the evaluation of the associated reward expectancies. The model is validated in a navigation task in which a rat is placed in a complex maze with multiple rewarding sites. We show that the rat mentally activates place cells to simulate paths, estimate their value, and make decisions, implementing two essential processes of model-based reinforcement learning algorithms of choice: look-ahead prediction and the evaluation of predicted states.

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

spatial navigation
mental simulation
computational model

hippocampal-striatal circuit
neural network


The isolation game: A game of distances We introduce a new multi-player geometric game, which we will refer to as the isolation game, and study its Nash equilibria and best or better response dynamics. The isolation game is inspired by the Voronoi game, competitive facility location, and geometric sampling. In the Voronoi game studied by Durr and Thang, each player's objective is to maximize the area of tier Voronoi region. In contrast, in the isolation game, each player's objective is to position herself as far away from other players as possible ill a bounded Space. Even though this game has a simple definition. we show that its game-theoretic behaviors are quite rich and complex. We consider various measures of farness from one player to a group of players and analyze their impacts to the existence of Nash equilibria and to the convergence of the best or better response dynamics: We prove that it is NP-hard to decide whether a Nash equilibrium exists, using either a very simple fatness measure in an asymmetric space or a slightly more sophisticated fatness measure in a symmetric space. Complementing these hardness results, we establish existence theorems for several special families of fatness measures in symmetric spaces: We prove that, for isolation games where each player wants to maximize her distance to her mth nearest neighbor, for any in, equilibria always exist. Moreover, there is always a better response sequence starting from any configuration that leads to a Nash equilibrium. We show that when m = 1 the game is a potential game. no better response sequence has a cycle. but when m > 1 the games are not potential. More generally, we study farness functions that give different weights to a player's distances to others based oil the distance rankings, and obtain both existence and hardness results when the weights are monotonically increasing or decreasing. Finally, we present results on the hardness of computing best responses when the space has a compact representation as a hypercube. (C) 2009 Elsevier B.V. All rights reserved.

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

algorithmic game theory
computational complexity


Model-based signature verification with rotation invariant features Non-linear rotation of signature patterns is one of the major difficulties to solve in off-line signature verification. This paper presents two models utilizing rotation invariant structure features to tackle the problem. In principle, the elaborately extracted ring-peripheral features are able to describe internal and external structure changes of signatures periodically. In order to evaluate match score quantitatively, discrete fast fourier transform is employed to eliminate phase shift and verification is conducted based on a distance model. In addition, the ring-hidden Markov model (HMM) is constructed to directly evaluate similar between test signature and training samples. With respect to the side effect of outlier training samples for stable statistical model and threshold estimation, we propose a selection strategy to improve the performance of system. Experimental results demonstrated that the proposed methods were effective to improve verification accuracy.

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

signature verification
rotation invariant
hmm

ring-peripheral feature
sample set pickup
threshold selection


Receiver IQ Imbalance Estimation via Pure Noise for 60 GHz Systems This paper proposes to estimate receiver (RX) IQ imbalance via pure noise for 60GHz millimeter-wave systems. We study the impact of RX IQ imbalance on noise, and derive the maximum-likelihood algorithm to acquire the imbalance parameters, which is decoupled from transmitter IQ imbalance, channel response, and carrier offset. Also, the proposed method has low computational complexity and meets the low-power and low-cost requirements of 60GHz systems. Moreover, the jitter performance of the estimation reaches the corresponding CramerRao lower bound under a wide range of imbalance parameters.

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

60ghz
iq imbalance
pure noise
cramerrao lower bound


Automatic segmentation of human facial tissue by MRICT fusion: A feasibility study The aim of this study was to develop automatic image segmentation methods to segment human facial tissue which contains very thin anatomic structures. The segmentation output can be used to construct a more realistic human face model for a variety of purposes like surgery planning, patient specific prosthesis design and facial expression simulation. Segmentation methods developed were based on Bayesian and Level Set frameworks, which were applied on three image types: magnetic resonance imaging (MRI), computerized tomography (CT) and fusion, in which case information from both modalities were utilized maximally for every tissue type. The results on human data indicated that fusion, thickness adaptive and postprocessing options provided the best muscle/fat segmentation scores in both Level Set and Bayesian methods. When the best Level Set and Bayesian methods were compared, scores of the latter were better. Number of algorithm parameters (to be trained) and computer run time measured were also in favour of the Bayesian method.

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 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 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 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 B O

medical image segmentation
data fusion
partial volume
level sets


Body patterns in cephalopods "Polyphenism" as a way of information exchange Here we overview the knowledge available on polyphenism in cephalopods: a peculiar characteristic of the behaviour of octopus, cuttlefish and squid. This is achieved through body patterning that is the mutable appearance of the skin of these species. After a short account on the organization of patterning and on the functions of this feature of cephalopods' behavioural repertoire, we discuss some preliminary evidence on the causation of this complex form of communication (either dishonest or in terms of signalling). (C) 2007 Elsevier B.V. All rights reserved.

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


evaluating the effectiveness of ict to support globally distributed pbl teams In the 21st century it is becoming increasingly common to work and learn in teams that are globally distributed. Such teams rely heavily on ICT to facilitate communication. There are many communication tools and technologies to choose from. This study investigates the effectiveness of a rich set of tools and considers if synergy exists between them. This paper reports and analyses the use of communication tools by students in a distributed Problem-based Learning (dPBL) environment. The PBL teams consisted of four students from Singapore and four from the UK. Teams had a rich set of synchronous and asynchronous communication tools available to them, including ISDN videoconference, WebCam video/audio, Microsoft NetMeeting Chat, Asynchronous drop box and threaded discussion Forum. This ethnographic study showed that semantic discussion threads included the use of all tools and enabled students to effectively co-construct meaning (and understanding). Students were able to deploy the use of different tools effectively to achieve the learning outcomes intended for various stages in the PBL cycle, with both asynchronous and synchronous media being considered of high importance.

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


Equitable edge-colorings of simple graphs An edge-coloring of a graph G is equitable if, for each v?V(G), the number of edges colored with any one color incident with v differs from the number of edges colored with any other color incident with v by at most one. A new sufficient condition for equitable edge-colorings of simple graphs is obtained. This result covers the previous results, which are due to Hilton and de Werra, verifies a conjecture made by Hilton recently, and substantially extends it to a more general class of graphs. 2010 Wiley Periodicals, Inc. J Graph Theory 66:175-197, 2011

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 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

equitable edge-coloring
f-coloring
f-chromatic index


Awareness and teamwork in computer-supported collaborations A contemporary approach to describing and theorizing about joint human endeavor is to posit 'knowledge in common' as a basis for awareness and coordination. Recent analysis has identified weaknesses in this approach even as it is typically employed in relatively simple task contexts. We suggest that in realistically complex circumstances, people share activities and not merely concepts. We describe a framework for understanding joint endeavor in terms of four facets of activity awareness: common ground, communities of practice, social capital, and human development. We illustrate the sort of analysis we favor with a scenario from emergency management, and consider implications and future directions for system design and empirical methods. (c) 2005 Elsevier B.V. All rights reserved.

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 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 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


Fast and stable explicit operator splitting methods for phase-field models Numerical simulations of phase-field models require long time computations and therefore it is necessary to develop efficient and highly accurate numerical methods. In this paper, we propose fast and stable explicit operator splitting methods for both one- and two-dimensional nonlinear diffusion equations for thin film epitaxy with slope selection and the CahnHilliard equation. The equations are split into nonlinear and linear parts. The nonlinear part is solved using a method of lines together with an efficient large stability domain explicit ODE solver. The linear part is solved by a pseudo-spectral method, which is based on the exact solution and thus has no stability restriction on the time-step size. We demonstrate the performance of the proposed methods on a number of one- and two-dimensional numerical examples, where different stages of coarsening such as the initial preparation, alternating rapid structural transition and slow motion can be clearly observed.

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

cahnhilliard equation
operator splitting methods

large stability domain explicit rungekutta methods


error-bounded antialiased rendering of complex environments In previous work, we presented an algorithm to accelerate z-buffer rendering of enormously complex scenes. Here, we extend the approach to antialiased rendering with an algorithm that guarantees that each pixel of the output image is within a user-specified error tolerance of the filtered underlying continuous image. As before, we use an object-space octree to cull hidden geometry rapidly. However, instead of using an image-space depth pyramid to test visibility of collections of pixel samples, we use a quadtree data structure to test visibility throughout image-space regions. When regions are too complex, we use quadtree subdivision to simplify the geometry as in Warnock's algorithm. Subdivison stops when the algorithm can either analytically filter the required region or bound the convolution integral appropriately with interval methods. To the best of our knowledge, this is the first algorithm to antialias with guaranteed accuracy scenes consisting of hundreds of millions of polygons.

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

geometry use knowledge subdivision visibility accuracy interval environments octree test rendering region quadtree image algorithm

collect
data structures
object
filtering
buffers
errors
user
method
interval arithmetic
space
antialiasing
complexity
shaders
continuation
integrability


An expert system to support the optimization of ion plating process: an OLAP-based fuzzy-cum-GA approach To cope with the issue of brain drain in today's competitive industrial environment, it is important to capture the relevant experience and knowledge in order to sustain the continual growth of company business. Studies indicate that a system, which is able to support optimization to enhance knowledge acquisition, is still needed. To address this issue, this paper proposes an expert system to support the optimization process based on expert advice derived from past experience. The expert system named fuzzy-based with Genetic Algorithm and On Line Analytical Processing embraces three emerging technologies including (i) fuzzy logic for mimicking the human thinking and decision-making mechanism, (ii) Genetic Algorithm for optimizing the analyzed knowledge, and (iii) On Line Analytical Processing for supporting data mining process through the capturing of relevant knowledge in terms of fuzzy rules for future decision-making as well as providing a mechanism to apply the obtained knowledge to support industrial processes. To validate the feasibility of the approach, a case study on the optimization of ion plating process has been conducted with promising results.

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

expert system
fuzzy logic
genetic algorithm

on-line analytic processing
database management system


efficiently identifying working sets in block i/o streams Identifying groups of blocks that tend to be read or written together in a given environment is the first step towards powerful techniques for device failure isolation and power management. For example, identified groups can be placed together on a single disk, avoiding excess drive activity across an exascale storage system. Unlike previous grouping work, we focus on identifying groupings in data that can be gathered from real, running systems with minimal impact. Using temporal, spatial, and access ordering information from an enterprise data set, we identified a set of groupings that consistently appear, indicating that these are working sets that are likely to be accessed together. We present several techniques to obtain groupings along with a discussion of what techniques best apply to particular types of real systems. We intend to use these preliminary results to inform our search for new types of workloads with a goal of identifying properties of easily separable workloads across different systems and dynamically moving groups in these workloads to reduce disk activity in large storage systems.

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

file-system contents
automated management


Coterie for generalized mutual exclusion problem This paper discusses the generalized mutual exclusion problem defined by H. Kakugawa and M. Yamashita. A set of processes shares a set of resources of an identical type. Each resource must be accessed by at most one process at any time. Each process may have different accessible resources. If two processes have no common accessible resource, it is reasonable to ensure a condition in resource allocation, which is called allocation independence in this paper, i.e., resource allocation to those processes must be performed without any interference. In this paper, we define a new structure, sharing structure coterie. By using a sharing structure coterie, the resource allocation algorithm proposed by H. Kakugawa and M. Yamashita ensures the above condition. We show a necessary and sufficient condition of the existence of a sharing structure coterie. The decision of the existence of a sharing structure coterie for an arbitrary distributed system is NP-complete. Furthermore, we show a resource allocation algorithm which guarantees the above requirement for distributed systems whose sharing structure coteries do not exist or are difficult to obtain.

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

distributed systems
coterie
resource allocation algorithm


Enhancing digital cephalic radiography with mixture models and local gamma correction We present a new algorithm, called the soft-tissue filter, that can make both soft and bone tissue clearly visible in digital cephalic radiographies under a wide range of exposures. It uses a mixture model made up of two Gaussian distributions and one inverted lognormal distribution to analyze the image histogram. The image is clustered in three parts: background, soft tissue, and bone using this model. Improvement in the visibility of both structures is achieved through a local transformation based on gamma correction, stretching, and saturation, which is applied using different parameters for bone and soft-tissue pixels. A processing time of 1 s for 5 M pixel images allows the filter to operate in real time. Although the default value of the filter parameters is adequate for most images, real-time operation allows adjustment to recover under- and overexposed images or to obtain the best quality subjectively. The filter was extensively clinically tested: quantitative and qualitative results are reported here.

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

digital radiography
histogram-based clustering
image enhancement
soft-tissue filter (stf)


Transition finite element families for adaptive analysis of axisymmetric elasticity problems In this paper, four transition element families that comprise five- to seven-node quadrilateral elements are developed based on the hybrid-stress and enhanced assumed strain (EAS) formulations for adaptive analyses of axisymmetric elasticity problems. For members in the first hybrid-stress family, a quasi-linear stress field with ten equilibrating stress modes is derived and employed. To study the effect of including more stress modes in the assumed stress field, another family with two additional stress modes is implemented. On the other hand, two EAS element families are constructed with respect to the incompatible displacement modes of two existing incompatible displacement transition element families. Several numerical examples are exercised. It can be seen that the first hybrid-stress family is the most accurate one among the proposed families. Moreover, the EAS families are close to the respective incompatible families in accuracy yet the former families are not only more efficient in computation but also more concise in formulation.

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

eas
axisymmetric
adaptive analysis
transition element


Design of compensated multiport waveguide junctions considering mechanization effects A new tool for the rigorous and efficient design of compensated multiport waveguide junctions, considering the mechanization effects due to low-cost manufacture techniques, is presented. Several new designs for a great variety of key components, present in modern microwave and millimetre-wave equipment, are proposed taking into account the introduction of rounded corners in the rectangular waveguide access ports. The new implemented tool permits to control and compensate for the potential degradation of the wide-band performance of such components prior to their fabrication, thus achieving an optimal design. All the presented results have been successfully validated by comparing the obtained simulated data with the results provided by a commercial software based on the finite-element method.

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

multiport waveguide junctions
mechanization effects


A dynamic logistics coordination model for evacuation and support in disaster response activities This paper describes an integrated location-distribution model for coordinating logistics support and evacuation operations in disaster response activities. Logistics planning in emergencies involves dispatching commodities (e.g., medical materials and personnel, specialised rescue equipment and rescue teams, food, etc.) to distribution centres in affected areas and evacuation and transfer of wounded people to emergency units. During the initial response time it is also necessary to set up temporary emergency centers and shelters in affected areas to speed up medical care for less heavily wounded survivors. In risk mitigation studies for natural disasters, possible sites where these units can be situated are specified according to risk based urban structural analysis. Logistics coordination in disasters involves the selection of sites that result in maximum coverage of medical need in affected areas. Another important issue that arises in such emergencies is that medical personnel who are on duty in nearby hospitals have to be re-shuffled to serve both temporary and permanent emergency units. Thus, an optimal medical personnel allocation must be determined among these units. The proposed model also considers this issue. The proposed model is a mixed integer multi-commodity network flow model that treats vehicles as integer commodity flows rather than binary variables. This results in a more compact formulation whose output is processed to extract a detailed vehicle route and load instruction sheet. Post processing is achieved by a simple routing algorithm that is pseudo-polynomial in the number of vehicles utilized, followed by the solution of a linear system of equations defined in a very restricted domain. The behavior and solvability of the model is illustrated on an earthquake scenario based on Istanbuls risk grid as well as larger size hypothetical disaster scenarios.

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

logistics in disaster response activities

integrated location and distribution problem

integer multi-commodity network flow problem


Quantifying local flow direction uncertainty Absolute elevation error in digital elevation models (DEMs) can be within acceptable National Map Accuracy standards, but still have dramatic impacts on field-level estimates of surface water flow direction, particularly in level regions. We introduce and evaluate a new method for quantifying uncertainty in flow direction rasters derived from DEMs. The method utilizes flow direction values derived from finer resolution digital elevation data to estimate uncertainty, on a cell-by-cell basis, in flow directions derived from coarser digital elevation data. The result is a quantification and spatial distribution of flow direction uncertainty at both local and regional scales. We present an implementation of the method using a 10-m DEM and a reference 1-m lidar DEM. The method contributes to scientific understanding of DEM uncertainty propagation and modeling and can inform hydrological analyses in engineering, agriculture, and other disciplines that rely on simulations of surface water flow.

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


Computational Acceleration for MR Image Reconstruction in Partially Parallel Imaging In this paper, we present a fast numerical algorithm for solving total variation and l(1) (TVL1) based image reconstruction with application in partially parallel magnetic resonance imaging. Our algorithm uses variable splitting method to reduce computational cost. Moreover, the Barzilai-Borwein step size selection method is adopted in our algorithm for much faster convergence. Experimental results on clinical partially parallel imaging data demonstrate that the proposed algorithm requires much fewer iterations and/or less computational cost than recently developed operator splitting and Bregman operator splitting methods, which candeal with a general sensing matrix in reconstruction framework, to get similar or even better quality of reconstructed images.

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

image reconstruction
partially parallel imaging


Calculating global illumination for glossy surfaces Photorealistic rendering is used to generate views of computer stored scenes. Global illumination algorithms take all transfers of light in the scene into account thereby creating a realistic looking image. Previously several approaches have been presented which are able to deal with global illumination for diffuse surfaces. More general surfaces are handled only by few methods. This work presents a new algorithm for the generation of photorealistic images for scenes with arbitrary surfaces. Initially particle tracing and a reconstruction phase are used to obtain a good approximation to the directionally dependent illumination in the scene. The illumination information is stored and can be used subsequently to generate images from different viewpoints directly from the stored solution. The whole system is structured into several independent phases and is designed to allow parallel processing and incremental refinement.

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

global illumination
particle tracing
glossy surfaces


Differential Regulation of Sympathetic Outflows to Vasoconstrictor and Thermoregulatory Effectors The medullary premotor neurons determining the sympathetic outflow regulating cardiac function and vasoconstriction are located in the rostral ventrolateral medulla (RVLM). The present study sought evidence for differential characteristics and baroreceptor reflex sensitivities between the sympathetic nerve activity (SNA) controlling brown adipose tissue (BAT) metabolism and thermogenesis and cardiovascular SNA such as that controlling mesenteric vasoconstriction via the splanchnic (SPL) nerve. The tonic discharge of sympathetic nerves is determined by the inputs to functionally specific sympathetic preganglionic neurons from supraspinal populations of premotor neurons. Under normothermic conditions, BAT SNA was nearly silent, while SPL SNA exhibited sustained, large-amplitude bursts. Disinhibition of neurons in the rostral raphe pallidus (RPa), a potential site of sympathetic premotor neurons controlling BAT SNA, or icv injection of prostaglandin E2, a pyrogenic stimulus, elicited a dramatic increase in BAT SNA. SPL SNA was strongly influenced by the baroreceptor reflex as indicated by a high coherence to the arterial pressure, while activated BAT SNA exhibited no correlation with the arterial pressure. Since these characteristics and reflex responses in sympathetic outflow have been shown to arise from the ongoing or altered discharge of sympathetic premotor neurons, the marked differences between SPL SNA and BAT SNA provide strong evidence supporting the hypothesis that vasoconstriction and thermogenesis (metabolism) are controlled by distinct populations of sympathetic premotor neurons, the former in the RVLM and strongly baroreceptor-modulated and the latter potentially in the RPa exhibiting little influence of baroreceptor reflex activation.

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

baroreceptor reflex
brown adipose tissue
raphe pallidus
rostral ventrolateral medulla
sympathetic nerve activity
thermogenesis
vasoconstriction

frequency domain
gaba inhibition
hypothermia


Fast stereo matching using rectangular subregioning and 3D maximum-surface techniques This paper presents a fast and reliable stereo matching algorithm which produces a dense disparity map by using fast cross correlation, rectangular subregioning (RSR) and 3D maximum-surface techniques in a coarse-to-fine scheme. Fast correlation is achieved by using the box-filtering technique whose speed is invariant to the size of the correlation window and by segmenting the stereo images into rectangular subimages at different levels of the pyramid. By working with rectangular subimages, not only can the speed of the correlation be further increased, the intermediate memory storage requirement can also be reduced. The disparity map for the stereo images is found in the 3D correlation coefficient volume by obtaining the global 3D maximum-surface rather than simply choosing the position that gives the local maximum correlation coefficient value for each pixel. The 3D maximum-surface is obtained using our new two-stage dynamic programming (TSDP) technique. There are two original contributions in this paper: (1) development of the RSR technique for fast similarity measure; and (2) development of the TSDP technique for efficiently obtaining 3D maximum-surface in a 3D volume. Typical running time of our algorithm implemented in the C language on a 512 x 512 image is in the order of a few seconds on a 500 MHz PC. A variety of synthetic and real images have been tested, and good results have been obtained.

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

similarity measure
stereo matching
pyramid

rectangular subregioning (rsr)
fast cross-correlation
coarse-to-fine
3d maximum-surface
two-stage dynamic programming (tsdp)
sub-pixel accuracy


A framework for generating network-based moving objects Benchmarking spatiotemporal database systems requires the definition of suitable datasets simulating the typical behavior of moving objects. Previous approaches for generating spatiotemporal data do not consider that moving objects often follow a given network. Therefore, benchmarks require datasets consisting of such "network-based" moving objects. In this paper, the most important properties of network-based moving objects are presented and discussed. Essential aspects are the maximum speed and the maximum capacity of connections, the influence of other moving objects on the speed and the route of an object, the adequate determination of the start and destination of an object, the influence of external events, and time-scheduled traffic. These characteristics are the basis for the specification and development of a new generator for spatiotemporal data. This generator combines real data (the network) with user-defined properties of the resulting dataset. A framework is proposed where the user can control the behavior of the generator by re-defining the functionality of selected object classes. An experimental performance investigation demonstrates that the chosen approach is suitable for generating large data sets.

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 B I O O O O O O B 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 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

spatiotemporal databases
data generation


Comparative study of the application of central composite face-centred (CCF) and BoxBehnken designs (BBD) to study the effect of demographic characteristics on HIV risk in South Africa In this study, Central composite face-centered and BoxBehnken designs were employed to study the main and interaction effects of demographic characteristics on the risk of HIV in South Africa. The demographic characteristics studied for each pregnant mother attending an antenatal clinic in South Africa were mothers age, partners age (fathers age), mothers level of education, and parity. The central composite face-centered and BoxBehnken designs showed that the risk of acquiring HIV status for an antenatal clinic attendee was highly sensitive to changes in pregnant womans age and her educational level, using the 2007 South African annual antenatal HIV and syphilis seroprevalence data. Individually the age of the pregnant womans partner and her parity had no significant effect on the HIV risk. However, the latter two demographic characteristics exhibited significant effects on the HIV risk in two-way interactions with other demographic characteristics. Using HIV as the optimization objective, the following summary statistics were obtained: R 2=0.99 (Central composite face-centered design) and R 2=0.99 (BoxBehnken design). The two-factor interactions model F values for the central composite and BoxBehnken designs were 7.99 and 88.29, respectively. These F values for the 2-factor interactions were significant with only a 0.12 and 0.01% chance that these model values were a result of noise. Adeq precision values of 8.84 and 31.33 for the central composite face-centered and BoxBehnken, respectively, suggested that these two-factor interactions models could be used to navigate the design spaces. Finally, the main effects and interactions plots illustrated that the HIV risk increased with the age of the pregnant woman.

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

demographic characteristics
seroprevalence data

response surface design
central composite design
face centered


an evaluation of tcp-based rate-control algorithms for adaptive internet streaming of h.264/svc Recent work in TCP video streaming indicates that multimedia streaming via TCP provides satisfactory performance when the achievable TCP throughput is approximately twice the media bit rate. However, these conditions may not be achievable on the Internet, e.g., when the delivery path offers insufficient bandwidth or becomes congested due to competing traffic. Therefore, adaptive streaming for videos over TCP is required and a number of rate-control algorithms for video streaming have been proposed and evaluated in the literature.\\ In this paper, we evaluate and compare three existing rate-control algorithms for TCP streaming in terms of the (PSNR) quality of the delivered video and in terms of the timeliness of delivery. The contribution of the paper is that, to the best of our knowledge, this is the first evaluation of TCP-based streaming in an Internet-like setting making use of the scalability features of the H.264/SVC video codec. Two simple bandwidth estimation algorithms and a priority-/deadline-driven approach are described to adapt the bit rates of, and transmit, the H.264/SVC video in a rate-distortion optimal manner. The results indicate that the three algorithms perform robustly in terms of video quality and timely delivery, both on under-provisioned links and in case of competing TCP flows. The priority-/deadline-driven technique is even more stable in terms of packet delays and jitter; thus, client buffers can be dimensioned more easily.

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

h.264/svc
tcp fairness
adaptive video streaming
rate control


Segmentation of structural features in cheese micrographs using pixel statistics Description of microscopic features is often accomplished by qualitative inspection of micrographs. However, assessing the differences responsible for the variation of rheological properties requires taking measurements of microscopic features. A statistically-founded algorithm is proposed for automatic identification of cheese micro-features in Scanning electron microscopy (SEM) imagery for quantitative analysis. Twenty SEM images of Ragusano cheese were recorded and manually labelled using a different colour coding for each of three features: whey pockets, fat globules, and protein matrix. The marked micrographs were used to train a statistical model. In turn, that model was used to mark the looked-for features on new images of the same type. Namely, pixel probabilities of belonging to the three classes above mentioned were computed, using pixel neighbourhoods at different scales. Each pixel was set within the most probable class. The proposed method could recognize the microstructure of Ragusano cheese in SEM images with higher accuracy (on average, 78.0% correct pixels) than other popular algorithms in the literature (e.g., Maximum Response 8 73.7% correct pixels). Being completely automatic in the operative phase, this algorithm allows to batch-process lots of images with no human intervention. It can also be used for any other application, since it can handle any number of phases.

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


A benchmark case for lattice Boltzmann: Turbulent dipole-wall collision A numerical experiment is presented that is taken from the recent literature. It has been devised as a benchmark case to test the quality of boundary conditions in numerical solvers for computational fluid dynamics. In this experiment, a two-dimensional system of two counter-rotating vertexes is brought into collision with a no-slip wall and rebounds from it. In the present paper, the benchmark is run with a lattice-Boltzmann numerical solver. Astonishingly accurate results are obtained with a straightforward boundary condition known under the name of bounce-back. This sample problem is also used to discuss techniques for the setup of an initial condition in the lattice Boltzmann method.

O B 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 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 B I O


Soft-computing techniques and ARMA model for time series prediction The challenge of predicting future values of a time series covers a variety of disciplines. The fundamental problem of selecting the order and identifying the time varying parameters of an autoregressive moving average model (ARMA) concerns many important fields of interest such as linear prediction, system identification and spectral analysis. Recent research activities in forecasting with artificial neural networks (ANNs) suggest that ANNs can be a promising alternative to the traditional ARMA structure. These linear models and ANNs are often compared with mixed conclusions in terms of the superiority in forecasting performance. This study was designed: (a) to investigate a hybrid methodology that combines ANN and ARMA models; (b) to resolve one of the most important problems in time series using ARMA structure and BoxJenkins methodology: the identification of the model. In this paper, we present a new procedure to predict time series using paradigms such as: fuzzy systems, neural networks and evolutionary algorithms. Our goal is to obtain an expert system based on paradigms of artificial intelligence, so that the linear model can be identified automatically, without the need of human expert participation. The obtained linear model will be combined with ANN, making up an hybrid system that could outperform the forecasting result.

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


Enhancing usability testing through datamining techniques: A novel approach to detecting usability problem patterns for a context of use Usability is a software attribute usually associated with the ease of use and to learn of a given interactive system. Nowadays usability evaluation is becoming an important part of software development, providing results based on quantitative and qualitative estimations. In this context, qualitative results are usually obtained through a Qualitative Usability Testing process which includes a number of different methods focused on analyzing the interface of a particular interactive system. These methods become complex when a large number of interactive systems belonging to the same context of use have to be jointly considered to provide a general diagnosis, as a considerable amount of information must be visualized and treated simultaneously. However, diagnosing the most general usability problems of a context of use as a whole from a qualitative viewpoint is a challenge for UE nowadays. Identifying such problems can help to evaluate a new interface belonging to this context, and to prevent usability errors when a novel interactive system is being developed. From a quantitative viewpoint, condensing results in singles scores, metrics or statistical functions is an acceptable solution for processing huge amounts of usability related information. Nevertheless, QUT processes need to keep their richness by prioritizing the what over the how much/how many questions related to the detection of usability problems. To cope with the above situation, this paper presents a new approach in which two datamining techniques (association rules and decision trees) are used to extend the existing Qualitative Usability Testing process in order to provide a general usability diagnosis of a given context of use from a qualitative viewpoint. In order to validate our proposal, usability problems patterns belonging to academic webpages in Spanish-speaking countries are assessed by processing 3450 records which store qualitative information collected by means of a Heuristic Evaluation.

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

qualitative usability testing
context of use
usability problem patterns
datamining
association rules
decision trees


Query Dispatching Tool Supporting Fast Access to Data Warehouse Data warehousing hastens the process of retrieving information needed for decision making. The spider web diversity between both end-users and data marts increases traffic, load, and delay in accessing the requested information. In this research, we have developed a query dispatching tool facilitating the access to the information within data marts, eventually data warehouse in fast, and an organized fashionable way. The dispatching tool takes the query, analyzes it, and decides which data mart as a destination that query should be forwarded to. This research is based on Ralph Kimball's methodology. The results show that the dispatching tool reduces the check time spent in the data dictionary within a logical side of the data warehouse deciding the intended data mart and hence, minimizing execution time.

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

data warehouse
query dispatching tool
execution time


One (96,20,4)-symmetric design and related nonabelian difference sets New (96,20,4)-symmetric design has been constructed, unique under the assumption of an automorphism group of order 576 action. The correspondence between a (96,20,4)-symmetric design having regular automorphism group and a difference set with the same parameters has been used to obtain difference sets in five nonabelian groups of order 96. None of them belongs to the class of groups that allow the application of so far known construction (McFarland, Dillon) for McFarland difference sets.

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


Compressible Distributions for High-Dimensional Statistics We develop a principled way of identifying probability distributions whose independent and identically distributed realizations are compressible, i.e., can be well approximated as sparse. We focus on Gaussian compressed sensing, an example of underdetermined linear regression, where compressibility is known to ensure the success of estimators exploiting sparse regularization. We prove that many distributions revolving around maximum a posteriori (MAP) interpretation of sparse regularized estimators are in fact incompressible, in the limit of large problem sizes. We especially highlight the Laplace distribution and regularized estimators such as the Lasso and basis pursuit denoising. We rigorously disprove the myth that the success of minimization for compressed sensing image reconstruction is a simple corollary of a Laplace model of images combined with Bayesian MAP estimation, and show that in fact quite the reverse is true. To establish this result, we identify nontrivial undersampling regions where the simple least-squares solution almost surely outperforms an oracle sparse solution, when the data are generated from the Laplace distribution. We also provide simple rules of thumb to characterize classes of compressible and incompressible distributions based on their second and fourth moments. Generalized Gaussian and generalized Pareto distributions serve as running examples.

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

compressible distribution
high-dimensional statistics
instance optimality
linear inverse problems
maximum a posteriori (map) estimator
order statistics
sparsity
statistical regression


Framework of grinding process modeling and simulation based on microscopic interaction analysis This paper describes a framework of grinding process modeling to understand the grinding fundamentals and design grinding processes with predictive performance. The model regards grinding process as a time dependent process and an integration of microscopic interactions in the wheel-workpiece contact zone, including cutting, plowing, and sliding as well as other frictional interactions. The grinding process control and design are in fact to manage and balance all these interactions. The principles of microscopic interactions are analyzed and used to correlate the grinding process input parameters and performance output. (C) 2010 Elsevier Ltd. All rights reserved.

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

grinding
modeling
simulation
framework
microscopic interactions


Remote temperature monitoring device using a multiple patients-coordinator set design approach This paper aims to develop a prototype for a web-based wireless remote temperature monitoring device for patients. This device uses a patient and coordinator set design approach involving the measurement, transmission, receipt and recording of patients temperatures via the MiWi wireless network. The results of experimental tests on the proposed system indicated a wider distance coverage and reasonable temperature resolution and standard deviation. The system could display the temperature and patient information remotely via a graphical-user interface as shown in the tests on three healthy participants. By continuously monitoring participants temperatures, this device will likely improve the quality of the health care of the patients in normal ward as less human workload is involved.

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

temperature
wireless
remote
monitoring
coordinator set


Effects of feeding ratio on flange bending in shear spinning The effects of feeding ratio on flange bending of shear spinning are investigated with analytical method. Firstly, influence of feeding ratio on total energy is analyzed utilizing the formula of shear spinning force and power derived by energy method. Subsequently, the connection between the deviation ratio and the thinning ratio, and the influence of feeding ratio on the thinning ratio are researched. Finally, the conclusions about the deviation ratio and flange bending are adopted to reveal the influential tendency of feeding ratio on flange bending. The results show that the flange bending towards headstock weakens with the increase of feeding ratio, which is verified by the experimental results very well. It indicates that the calculation method in this paper is reasonable.

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

shear spinning
flange bending
feeding ratio
energy method


Convergence and superconvergence of staggered discontinuous Galerkin methods for the three-dimensional Maxwells equations on Cartesian grids In this paper, a new type of staggered discontinuous Galerkin methods for the three dimensional Maxwells equations is developed and analyzed. The spatial discretization is based on staggered Cartesian grids so that many good properties are obtained. First of all, our method has the advantages that the numerical solution preserves the electromagnetic energy and automatically fulfills a discrete version of the Gauss law. Moreover, the mass matrices are diagonal, thus time marching is explicit and is very efficient. Our method is high order accurate and the optimal order of convergence is rigorously proved. It is also very easy to implement due to its Cartesian structure and can be regarded as a generalization of the classical Yees scheme as well as the quadrilateral edge finite elements. Furthermore, a superconvergence result, that is the convergence rate is one order higher at interpolation nodes, is proved. Numerical results are shown to confirm our theoretical statements, and applications to problems in unbounded domains with the use of PML are presented. A comparison of our staggered method and non-staggered method is carried out and shows that our method has better accuracy and efficiency.

O O B 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 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 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 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

maxwells equations
gauss law
superconvergence
yees scheme

staggered discontinuous galerkin method
energy conservation
optimal convergence
edge element method
dispersion error


The Particle-Continuum method: an algorithmic unification of particle-in-cell and continuum methods A new numerical algorithm that encompasses both the deltaf particle-in-cell (PIC) method and a continuum method has been developed, which is an extension to Denavit's [J. Comput. Phys. 9 (1972) 75] original "hybrid" method. In this article we describe this new Particle-Continuum algorithm in general, and we note our methods of interpolation. The issue of phase space convergence of this algorithm is discussed. We analyze the induced numerical diffusion of such an algorithm and compare theory with results. We also created a simple problem that demonstrates this algorithm solves the "growing weight" problem. (C) 2004 Elsevier B.V. All rights reserved.

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

plasma kinetic vlasov particle simulation


Hybrid wire-surface wave interconnects for next-generation networks-on-chip Networks-on-chip (NoC) is a communication paradigm that has emerged to tackle different on-chip challenges and satisfy different demands in terms of high performance and economical interconnect implementation. However, merely metal-based NoC pursuit offers limited scalability with the relentless technology scaling especially in global communications. To meet the scalability demand, this study proposes a new hybrid architecture empowered by both metal interconnect and Zenneck surface waves interconnects (SWIs). This architecture reduces the NoC average hop count between any communication pairs, which has been reflected as a better average delay and throughput. Furthermore, SWI enables more efficient power dissipation and faster cross the chip signal propagation. The authors' initial results based on a cycle-accurate simulator demonstrate the effectiveness of the proposed system architecture, such as significant power reduction (23%), large average delay reduction (34%) and higher throughput (35%) compared with regular NoC. These results are achieved with negligible hardware and area overhead. This study explores promising potentials of SWI for future complex global communication.

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

noc
economical interconnect
global communications
zenneck surface waves interconnects
swi
chip signal propagation

economics
integrated circuit interconnections
network-on-chip
hybrid wire-surface wave interconnects
next-generation networks-on-chip


Decision Strategies for a P2P Computing System Peer-to-Peer (P2P) computing (also called 'public-resource computing') is an effective approach to perform computation of large tasks. Currently used P2P computing systems (e.g., BOINC) are most often centrally managed, i.e., the final result of computations is created at a central node using partial results - what may be not efficient in the case when numerous participants are willing to download the final result. In this paper, we propose a novel approach to P2P computing systems. We assume that results can be delivered to all peers in a distributed way using three types of network flows: unicast, Peer-to-Peer and anycast. We describe our concept of the system architecture with a special focus on the decision strategies developed for system participants. Using our discrete realtime simulator we evaluate the proposed strategies in various scenarios and present a comprehensive analysis of obtained results. According to obtained results, the Peer-to-Peer flow provides lower operational cost of the computing system compared to unicast and anycast flows. Moreover, an appropriate selection of decision strategy can significantly reduce the operational cost.

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


context-sensitive authorization in interaction patterns Main requirement of recent computing environments, like mobile and then ubiquitous computing, is to adapt applications to context. On the other hand, access control generally trust users once they have authenticated, despite the fact that they may reach unauthorized situations. We analyse how dynamic information can be used to improve security in the authorization process, and what are the implications when applied to interaction patterns. We experiment and validate our approach using context as an authorization factor for eventing in Web service for device (like UPnP or DPWS).

O O O 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

context-sensitive authorization
dynamic authorization
context-awareness


Acceptance of blog usage: The roles of technology acceptance, social influence and knowledge sharing motivation Recently, there has been a dramatic proliferation in the number of blogs; however, little is published about what motivates people to participate in blog activities. Based on the theory of reasoned action, we developed a model involving technology acceptance, knowledge sharing and social influences. A survey of 212 blog participants found strong support for the model. The results indicated that ease of use and enjoyment, and knowledge sharing (altruism and reputation) were positively related to attitude toward blogging, and accounted for 78% of the variance. On the other hand, social factors (community identification) and attitude toward blogging significantly influenced a blog participant's intention to continue to use blogs. Together they explain 83% of the variance of intention to blog.

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

blog
sharing motivation
social influence


Influence of heterogeneous and anisotropic tissue conductivity on electric field distribution in deep brain stimulation The aim was to quantify the influence of heterogeneous isotropic and heterogeneous anisotropic tissue on the spatial distribution of the electric field during deep brain stimulation (DBS). Three finite element tissue models were created of one patient treated with DBS. Tissue conductivity was modelled as (I) homogeneous isotropic, (II) heterogeneous isotropic based on MRI, and (III) heterogeneous anisotropic based on diffusion tensor MRI. Modelled DBS electrodes were positioned in the subthalamic area, the pallidum, and the internal capsule in each tissue model. Electric fields generated during DBS were simulated for each model and target-combination and visualized with isolevels at 0.20 (inner), and 0.05Vmm?1 (outer). Statistical and vector analysis was used for evaluation of the distribution of the electric field. Heterogeneous isotropic tissue altered the spatial distribution of the electric field by up to 4% at inner, and up to 10% at outer isolevel. Heterogeneous anisotropic tissue influenced the distribution of the electric field by up to 18 and 15% at each isolevel, respectively. The influence of heterogeneous and anisotropic tissue on the electric field may be clinically relevant in anatomic regions that are functionally subdivided and surrounded by multiple fibres of passage.

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

deep brain stimulation
diffusion tensor
finite element
model


Traffic: A novel geometric algorithm for fast wire-optimized floorplanning As the size and complexity of very large scale integrated (VLSI) circuits increase, the need for faster floorplanning algorithms also grows. This paper introduces trapezoidal floorplanning for integrated circuits (Traffic), a new method for creating wire- and area-optimized floorplans. Through the use of connectivity grouping, simple geometry, and a constrained brute-force approach, Traffic achieves an average of 18% lower wire estimate than simulated annealing (SA) in orders of magnitude less time. This speed allows designers to rapidly explore a large circuit design space, to evaluate small changes to big circuits, to fit bounding boxes, and to produce initial solutions for other floorplanning algorithms.

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

constructive floorplanning
fixed-outline floor-planning
wire optimization


Flipping cubical meshes We define and examine flip operations for quadrilateral and hexahedral meshes, similar to the flipping transformations previously used in triangular and tetrahedral mesh generation.

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

flip graph connectivity
hexahedral meshing
mesh improvement
quadrilateral meshing


Array errors active calibration algorithm based on instrumental sensors The array mutual coupling, gain-phase errors and sensor position errors would significantly degrade the performance of high-resolution direction of arrival (DOA) estimation algorithms. Aiming at the combined influences of the above three array errors, a kind of active calibration algorithm is presented with the help of instrumental sensors in this paper. Firstly, the integrated effects of the three array errors are shown to be equivalent to angularly dependent gain-phase errors. Then, a non-linear least square (LS) optimization model for the three array errors is established through an auto-calibration algorithm using auxiliary sensors, and the corresponding resolving algorithms of the LS optimization problem are given according to the different models of array errors matrix. Next, the parameter estimation uniqueness of the proposed algorithms is analyzed in detail and an improvement strategy is given. Finally, the effectiveness of the novel algorithm is validated by simulations.

B I O O O O O B 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 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 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 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

array errors
sensor position errors
instrumental sensors

array calibration
mutual coupling effect
gain-phase errors


improving the general monitoring system Monitoring network devices is critical to avoid downtime in an organization from solvable technical problems. Available methods to monitor hardware are often lacking in areas such as data gathering and visual representation of that data. Gathering accurate measurements at a consistent rate is important for identifying and solving problems. Interpretation of the results is also vital. Visually based data representation has become a standard methodology for many users, as it allows quick analysis of gathered measurements. This paper offers a solution that provides improved device handling as well as an improved visual representation of results from network devices, and increased speed in the data gathering process.

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


Necessary and sufficient condition for multistability of neural networks evolving on a closed hypercube Multistability is analyzed for neural networks evolving in a closed hypercube. A necessary and sufficient condition for multistability is obtained. The condition is applicable to nonsymmetric cooperative neural networks. The condition can easily be checked by numerical means. A sharp bound between multistable and globally stable networks is obtained.

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

differential variational inequalities
cooperative dynamical systems
nonsmooth dynamical systems


A robust and flexible digital rights management system for home networks A robust and flexible Digital Rights Management system for home networks is presented. In the proposed system, the central authority delegates its authorization right to the local manager in a home network by issuing a proxy certificate, and the local manager flexibly controls the access rights of home devices on digital contents with its proxy certificate. Furthermore, the proposed system provides a temporary accessing facility for external devices and achieves strong privacy for home devices. For the validation of delegated rights and the revocation of compromised local managers, a hybrid mechanism combining OCSP validation and periodic renewal of proxy certificates is also presented.

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

digital rights management
home network
proxy certificate


Jackson Type Generalization of Nonlinear Integral Operators In this work, we provides a global smoothness preservation result of a Jackson-type generalization of the nonlinear convolution operator defined by Angeloni and Vinti in [4]. Convergence in variation is also studied.

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

nonlinear integral operators
jackson type generalization
convergence in variation


A variational approach to nonlinear two-point boundary value problems A variational formulation is established for a nonlinear two-point boundary value problem, an analytical solution is obtained using the Ritz method, and the obtained solution is valid for the whole solution domain.

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


Cross-domain sentiment classification via topical correspondence transfer We propose a novel algorithm, called topical correspondence transfer (TCT) for cross-domain sentiment classification. The proposed framework is achieved by learning the domain-specific information from different domains into unified topics, with the help of shared topics across all domains. An objective function is defined to simultaneously learn a topical representation and document sentiment prediction with the model.

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

sentiment classification
topical correspondence transfer


Introducing RFID at Middlesex University learning resources Purpose - To describe the first year of the implementation of radio frequency identification (RFID) in Middlesex University Learning Resources. Design/methodology/approach - The technology is explained in detail to set the scene. Information on the implementation is presented in chronological order. Findings - Problems which would generally be applicable to other installations in these early days of the use of RFID in libraries are pointed out. Practical implications - It is possible to implement RFID without too much lead time, although, had longer been available, some aspects would have gone more smoothly. Originality/value - Contains valuable information for other libraries considering or intending to introduce RFID.

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

university libraries
radio systems
library systems


Compositional reasoning for weighted Markov decision processes Weighted Markov decision processes (MDPs) have long been used to model quantitative aspects of systems in the presence of uncertainty. However, much of the literature on such MDPs takes a monolithic approach, by modelling a system as a particular MDP; properties of the system are then inferred by analysis of that particular MDP. In contrast in this paper we develop compositional methods for reasoning about weighted MDPs, as a possible basis for compositional reasoning about their quantitative behaviour. In particular we approach these systems from a process algebraic point of view. For these we define a coinductive simulation-based behavioural preorder which is compositional in the sense that it is preserved by structural operators for constructing weighted MDPs from components. For finitary convergent processes, which are finite-state and finitely branching systems without divergence, we provide two characterisations of the behavioural preorder. The first uses a novel quantitative probabilistic logic, while the second is in terms of a novel form of testing, in which benefits are accrued during the execution of tests. (C) 2013 Elsevier B.V. All rights reserved.

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

simulation
testing preorder
modal logic
compositionality