A linearization method for mixed 0-1 polynomial programs This paper proposes a concise method for solving mixed 0-1 polynomial programming problems to obtain a global optimal solution. Given a mixed 0-1 polynomial term z = c(1)x(1)x(2)....x(n)y, where x(1), x(2),..., x(n) are 0-1 integer variables, y is a continuous variable, and c(t) is either a positive or a negative coefficient; we can transform z into a set of auxiliary constraints. Based on this transformation, the original mixed 0-1 polynomial program can then be solved directly by the branch-and-bound method. In addition, the proposed model for solving a mixed 0-1 polynomial problem is expressed in a much more compact way, and also uses fewer additional 0-1 variables and auxiliary constraints than the previous methods, such as those proposed by Glover, Oral-Kettani, and Li. The analytical superiority of this concise method in terms of the number of iterations and execution times can be seen, through a computational experiment conduced on a set of generated mixed 0-1 polynomial problems. Scope and purpose Decision-making problems, such as facility layout,job assignment, or Communication network designs are most often formulated as mixed integer problems. To solve this form of problem, Glover transformed a binary quadratic problem with n of 0-1 variables into linear inequalities by adding 4n auxiliary constraints and n continuous variables. Oral and Kettani later proposed another linearization procedure for binary quadratic and cubic problems, which substantially improved the technique of Glover by reducing the number of auxiliary constraints. Recently, Li presented a more general linearization approach for solving mixed 0-1 polynomial problems. Compared with previous model, Li's model is more promising for use in solving practical problems. This paper shows that it is possible to further modify Li's model by reducing the number of extra variables and auxiliary constraints in the linearization process. Some test examples with various sizes of variables demonstrate that this model uses less CPU time and has fewer iterations than Li's model, while reaching the same optimal solution. (C) 2000 Elsevier Science Ltd. AIL rights reserved.

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


Dynamic programming algorithms for scheduling parallel machines with family setup times We address the problem of scheduling jobs with family setup times on identical parallel machines to minimize total weighted flowtime. We present two dynamic programming algorithms a backward algorithm and a forward algorithm and we identify characteristics of problems where each algorithm is best suited. We also derive two properties that improve the computational efficiency of the algorithms. While most production schedulers must balance conflicting goals of high system efficiency and timely completion of individual jobs, consideration of this conflict is underdeveloped in the scheduling literature. This paper examines a model that incorporates a fundamental cause of the efficiency/timeliness conflict in practice. We propose solution methodologies and properties of an optimal solution for the purpose of exposing insights that may ultimately be useful in research on more complex models.

B I O O 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 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


A DHT-Aided Chunk-Driven Overlay for Scalable and Efficient Peer-to-Peer Live Streaming Internet-based video streaming applications are becoming more and more popular, attracting millions of online viewers every day. The incredible growth of viewers, dynamics of participants, and high video quality of service (QoS) requirement pose scalability, availability, and low-latency challenges to peer-to-peer (P2P) live video streaming systems. Tree-based systems have low-delay but are vulnerable to churn, while mesh-based systems are churn-resilient but suffer from high delay and overhead. Also, both structures cannot make full utilization of the bandwidth in the system. To tackle the challenges, we propose a DHT-aided chunk-driven overlay (DCO). It introduces a scalable DHT ring structure into a mesh-based overlay to efficiently manage video stream sharing. DCO includes a two-layer hierarchical DHT-based infrastructure, a chunk sharing algorithm, and a video provider selection algorithm. It selects stable nodes to form a scalable DHT-based infrastructure. The nodes in the DHT serve as distributed matchmakers between video providers and requesters. To motivate stable nodes to serve as the DHT nodes, we introduce an incentive mechanism based on the game theory. Aided by DHT, DCO guarantees stream chunk availability and assigns to a chunk requester a provider among all available providers in the system so that stream chunks are transmitted along a dynamic tree with top-down decreasing node bandwidth. In this way, DCO takes full advantage of available bandwidth in the system and, at the same time, provides high scalability and low latency. Experimental results show the superior performance of DCO compared with mesh-based and tree-based systems, and the effectiveness of the incentive mechanism and provider selection algorithm.

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


The complexity of changing colourings with bounded maximum degree Let G be a graph, x, y epsilon V(G), and phi : V (G) -> [K] a k-colouring of G such that phi(x) = phi(y). If Delta(G) >= k + root k - 1 then the following question is NP-complete: Does there exist a k-colouring phi' of such that phi' (x) not equal phi (Y)? Conversely, if Delta(G) <= k +root k - 3 then the problem is polynomial time. (C) 2010 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

combinatorial problems
computational complexity
graph algorithms


energy-saving dvfs scheduling of multiple periodic real-time tasks on multi-core processors This paper addresses an energy-saving scheduling scheme of periodic real-time tasks with the capability of dynamic voltage and frequency scaling, on the lightly loaded multi-core platform containing more processing cores than running tasks. First, it is shown that the problem of minimizing energy consumption of real-time tasks is NP-hard even on the lightly loaded multi-core platform. Next a heuristic scheduling scheme is proposed to find an energy-efficient schedule with a low time complexity while meeting the deadlines of real-time tasks. The scheme exploits overabundant cores to reduce energy consumption using parallel execution and turns off the power of unused or rarely used cores. Evaluation shows that the proposed scheme saves up to 64\% energy consumption of the existing method executing each task on a separate core.

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

multi-core processor
task scheduling
real-time system
energy minimization


an evaluation of the n. mpc design environment Presents experimentally derived performance data on the N.mPc system. Data describing the type, size, and speed of simulations is presented. The implications of using the ISP' Hardware Description Language in constructing various models of the same components are considered. A set of design examples are presented to illustrate the range of simulation capabilities.

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

design environment
capabilities
simulation
hardware description language
examples
size
performance
design
data
evaluation


Biomechanical modeling of the human head for physically based, nonrigid image registration The accuracy of image-guided neurosurgery generally suffers from brain deformations due to intraoperative changes. These deformations cause significant changes of the anatomical geometry (organ shape and spatial interorgan relations), thus making intraoperative navigation based on preoperative images error prone. In order to improve the navigation accuracy, we developed a biomechanical model of the human head based on the finite element method, which can be employed for the correction of preoperative images to cope with the deformations occurring during surgical interventions. At the current stage of development, the two-dimensional (2-D) implementation of the model comprises two different materials, though the theory holds for the three-dimensional (3-D) case and is capable of dealing with an arbitrary number of different materials. For the correction of a preoperative image, a set of homologous landmarks must be specified which determine correspondences. These correspondences can be easily integrated into the model and are maintained throughout the computation of the deformation of the preoperative image. The necessary material parameter values have been determined through a comprehensive literature study. Our approach has been tested for the case of synthetic images and yields physically plausible deformation results. Additionally, we carried out registration experiments with a preoperative MR image of the human head and a corresponding postoperative image simulating an intraoperative image. We found that our approach yields good prediction results, even in the case when correspondences are given in a relatively small area of the image only.

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

biomechanical model
finite element method

elasticity theory
image correction
inhomogeneous materials
intraoperative image correction


a system framework and key techniques of fragments assembly for restoration of historical relics based on grid Computer-aided relic recovery is an important and urgent research in archaeology, especially virtual assembly of historical relic fragments using computer graphics, image processing and virtual reality techniques. In the computer-aided assembly of historical relic fragments, many algorithms cooperate, and heavy load and difficult use of the algorithms further the difficulty of implementation. Grid is used to enable the coordinated use of distributed resources. In this paper, a way is discussed to make algorithms more effectively shared and used, and how to assemble historical relic fragments based on Grid-computing technologies. We first present the framework of grid-based archaeological fragment assembly system, and then discuss the key technologies and implementation details.

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


Facial Age Estimation by Learning from Label Distributions One of the main difficulties in facial age estimation is that the learning algorithms cannot expect sufficient and complete training data. Fortunately, the faces at close ages look quite similar since aging is a slow and smooth process. Inspired by this observation, instead of considering each face image as an instance with one label (age), this paper regards each face image as an instance associated with a label distribution. The label distribution covers a certain number of class labels, representing the degree that each label describes the instance. Through this way, one face image can contribute to not only the learning of its chronological age, but also the learning of its adjacent ages. Two algorithms, named IIS-LLD and CPNN, are proposed to learn from such label distributions. Experimental results on two aging face databases show remarkable advantages of the proposed label distribution learning algorithms over the compared single-label learning algorithms, either specially designed for age estimation or for general purpose.

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

age estimation
face image
label distribution


Extraction and Recognition Methods of Vehicle Driving Tendency Feature Based on Driver-vehicle-environment Dynamic Data under Car Following Driving tendency is the comprehensive embodiment of driver's physiological and psychological characteristics. It reflects driver's psychological condition during the process of driving. Identification of the driving tendency has great significance to researching of the driver assistant system, especially the active security warning system. In this paper, data from simulative driving and real driving experiment of different drivers (risk-taking, cautious and conservative type, etc) under the state of car-following flow are obtained through questionnaires on psychological test. The feature eigenvectors with good ability to classify the type of driving tendency is extracted based on rough set theory. Dynamic recognition method of driving tendency is put forward with model calibration and verification making use of real data. The results of verification are compared with the results of the questionnaires. It is shown that the pattern recognition model is feasible, and can realize real-time recognition of the driver tendency under the state of car-following.

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

driving tendency
pattern recognition
rough set theory


Iterative sliced inverse regression for segmentation of ultrasound and MR images In this study, we propose an integrated approach based on iterative sliced inverse regression (ISIR) for the segmentation of ultrasound and magnetic resonance (MR) images. The approach integrates two stages. The first is the unsupervised clustering which combines multidimensional scaling (MDS) with K-Means. The dimension reduction based on MDS is employed to obtain fewer representative variates as input variables for K-Means. This step intends to generate the initial group labels of the training data for the second stage of supervised segmentation. We then combine the SIR with the nearest mean classifier (NMC) or the support vector machine (SVM) to iteratively update the group labels for supervised segmentation. The method of SIR is introduced by Li [Sliced inverse regression for dimension reduction. J. Am. Stat. Assoc. 86 (1991) 316342] to explore the effective dimension reduction (e.d.r.) directions from the training data embedded in high-dimensional space. The test data are then projected onto these directions and the classifiers are further applied to classify the test data. The integrated approach based on ISIR is evaluated on simulated and clinical images, which include ultrasound and MR images. The evaluation results indicate that this approach provides an improvement of image segmentation over the methods to be compared without dimension reduction.

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

unsupervised clustering
dimension reduction
multidimensional scaling
sliced inverse regression
nearest mean classifier


Improving translation quality stability using Bayesian predictive adaptation ? Bayesian predictive adaptation (BPA) is presented for model adaptation in SMT. Results are presented for a standard adaptation task (JHU SummerWorkshop 2012). Comparison between different sampling strategies. In-depth analysis of stability of most common optimisation algorithms in SMT. Computational cost comparison among the methods presented.

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

bayesian methods
natural language processing
machine translation


Ant colony optimization with greedy migration mechanism for node deployment in wireless sensor networks Node deployment is one of the most crucial issues in wireless sensor networks because it determines the deployment cost, the detection capability of the networks, and even the network lifetimes. To solve such a problem is an intricate task with realistic deployment factors such as deployment cost, connectivity guarantee, load balancing and channel collisions. In this paper, we consider the problem of grid-based coverage with low-cost and connectivity-guarantee (GCLC), and propose a novel deployment approach, ACO-Greedy, to settle this question. This approach is based on the ant colony optimization with greedy migration mechanism, which can quickly complete the full coverage, and markedly decrease the deployment cost. In addition, ACO-Greedy can dynamically adjust the sensing/communication radius to alleviate the energy hole problem and prolong the network lifetime. The simulation results reveal that our developed approach can not only decrease the deployment cost remarkably, but also effectively balance power consumption among sensor nodes and prolong the network lifetime in grid-based WSNs.

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

wireless sensor networks
node deployment
energy hole
ant colony optimization
greedy migration


Wheeze detection based on time-frequency analysis of breath sounds Abnormal breath sounds like wheezes are observed in patients with obstructive pulmonary diseases. The aim of this study was to construct an automatic technique for wheeze detection and monitoring using spectral analysis. Wheezes from 13 patients with diagnosed asthma, chronic obstructive pulmonary disease and pneumonia were recorded and a time-frequency wheeze detector (TF-WD) based on TF wheeze characteristics was constructed. The TF-WD was evaluated using 337 wheezes by comparing its findings with those from clinical auscultation performed by two experts. In addition, the TF-WD was tested against artificial noise. The experimental and testing results justified the efficient performance and high noise robustness of the TF-WD.

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

time-frequency analysis
inverse/short-time fourier transform
noise stress test
copd


Identifying a non-commensurable fractional transfer function from a frequency response Levy?s identification method is expanded to non-commensurable fractional models. Numerical and empirical ways of finding the orders involved are justified. Models for the human arm are found as an application.

O O O O O O O O B I 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


Characteristics of beryllium bonds; a QTAIM study The nature of beryllium bonds formed between BeX2 (X is H, F and Cl) and some Lewis bases have been investigated. The distribution of the Laplacian of electron density shows that there is a region of charge depletion around the Be atom, which, according to Laplacian complementary principal, can interact with a region of charge concentration of an atom in the base and form a beryllium bond. The molecular graphs of the investigated complexes indicate that beryllium in BeH2 and BeF2 can form "beryllium bonds" with O, N and P atoms but not with halogens. In addition, eight criteria based on QTAIM properties, including the values of electron density and its Laplacian at the BCP, penetration of beryllium and acceptor atom, charge, energy, volume and first atomic moment of beryllium atom, have been considered and compared with the corresponding ones in conventional hydrogen bonds. These bonds share many common features with very strong hydrogen bonds, however, some differences have also been observed.

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 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 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 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

laplacian of electron density
weak interactions


New variants of the criss-cross method for linearly constrained convex quadratic programming In this paper, S. Zhang's [Eur. J. Oper. Res. 116 (1999) 607] new and more flexible criss-cross type algorithms (with LIFO and most-often-selected-variable pivot rules) are generalized for linearly constrained convex primaldual quadratic programming problems. These criss-cross type algorithms are different from the one described in Klafszky and Terlaky [Math. Oper. und Stat. Ser. Optim. 24 (1992) 127]. Even though the finiteness proof of these new criss-cross type algorithms is similar to the original one for the algorithm of Klafszky and Terlaky (in the sense that both these proofs are based on the orthogonality theorem), more cases have to be considered due to the flexibility of pivot (LIFO/most-often-selected-variable) rules, which requires a deeper and more careful analysis. When the primaldual problem is a linear programming problem (no quadratic terms in the objective function), the structure of the corresponding linear complementarity problem is simpler (i.e. the matrix of the problem is skew-symmetric). For such problem pairs, our proof of finiteness simplifies to the proof of Ills and Mszros' [Yugoslav J. Oper. Res. 11 (2001) 17] and provides a new finiteness proof for S. Zhang's criss-cross type 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 O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

linearly constrained convex quadratic optimization


Multicast routing and wavelength assignment with delay constraints in WDM networks with heterogeneous capabilities ? Because optical wavelength division multiplexing (WDM) networks are expected to be realized for building up backbone in the near future, multicasting in WDM networks needs to be addressed for various network applications. This paper studies an extended multicast routing and wavelength assignment (RWA) problem called multicast routing and wavelength assignment with delay constraint (MRWA-DC) that incorporates delay constraints in WDM networks having heterogeneous light splitting capabilities. The objective is to find a light-forest whose multicast cost, defined as a weighted combination of communication cost and wavelength consumption, is minimum. An integer linear programming (ILP) model is proposed to formulate and solve the problem. Experimental results show that using CPLEX to solve the ILP formulation can optimally deal with small-scale networks. Therefore, we develop a heuristic, near-k-shortest-path heuristic (NKSPH), to solve the problem in large-scale networks. Numerical results indicate that the proposed heuristic algorithm can produce approximate solutions of good quality in an acceptable time.

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


Persuasion and social perception of human vs. synthetic voice across person as source and computer as source conditions There is evidence that people react more positively when they are presented with faces that are consistent with their voices. Nass and Brave [2005]. Wired for speech: How voice Activates and Advances the Humancomputer Relationship. MIT Press, Cambridge, MA] found that computerized and human faces were perceived more positively when paired, respectively, with synthesized versus human voices than when paired with inconsistent voices. The present study sought to examine whether this type of inconsistency would effect perceptions of persuasive messages delivered by humans versus computers. We created a situation in which reactions to computer synthesized speech were compared to human speech when the speech was either from a person or a computer. This paper presents two studies, one using audio taped stimuli and one using videotaped stimuli, with type of speech (human versus computer synthesized) manipulated factorially with source (person versus computer). As hypothesized, both studies suggest that in the human as source condition, human voice is perceived more favorably than synthetic voice. However, in the computer as source condition, both human and computer voice were rated similarly. We discuss these findings in terms of consistency as well as group processes effects that may be occurring.

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

human factors
speech technology
ingroup/outgroup
talking computers


Selecting forwarding neighbors in wireless ad hoc networks Broadcasting is a fundamental operation which is frequent in wireless ad hoc networks. A simple broadcasting mechanism, known as flooding, is to let every node retransmit the message to all its 1-hop neighbors when receiving the first copy of the message. Despite its simplicity, flooding is very inefficient and can result in high redundancy, contention, and collision. One approach to reducing the redundancy is to let each node forward the message only to a small subset of 1-hop neighbors that cover all of the node's 2-hop neighbors. In this paper we propose two practical heuristics for selecting the minimum number of forwarding neighbors: an O(n log n) time algorithm that selects at most 6 times more forwarding neighbors than the optimum, and an O(n log(2) n) time algorithm with an improved approximation ratio of 3, where n is the number of 1- and 2-hop neighbors. The best previously known algorithm, due to Bronnimann and Goodrich [2], guarantees O(1) approximation in O(n(3) log n) time.

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

broadcast
approximation algorithms
unit-disk graphs
disk cover


associating characters with events in films The work presented here combines the analysis of a film's audiovisual features with the analysis of an accompanying audio description. Specifically, we describe a technique for semantic-based indexing of feature films that associates character names with meaningful events. The technique fuses the results of event detection based on audiovisual features with the inferred on-screen presence of characters, based on an analysis of an audio description script. In an evaluation with 215 events from 11 films, the technique performed the character detection task with Precision = 93\% and Recall = 71\%. We then go on to show how novel access modes to film content are enabled by our analysis. The specific examples illustrated include video retrieval via a combination of event-type and character name and our first steps towards visualization of narrative and character interplay based on characters occurrence and co-occurrence in events.

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


A hybrid bandwidth selection methodology for kernel density estimation A bandwidth selection method that combines the concept of least-squares cross-validation and the plug-in approach is being introduced in connection with kernel density estimation. A simulation study reveals that this hybrid methodology outperforms some commonly used bandwidth selection rules. It is shown that the proposed approach can also be readily employed in the context of variable kernel density estimation. We conclude with two illustrative examples.

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

kernels
least-squares cross-validation
plug-in estimates


a type system extension for middleware interactions Object-oriented programming languages such as Java provides inadequate support for advanced method invocation strategies in distributed applications. Invocation semantics such as reliable unicast and multicast must be implemented based on primitive, unreliable unicast mechanisms such as Java RMI and Socket communication. This forces developers to devise ad hoc communication strategies, which is a repetitive and error-prone process. Moreover, these communication strategies are entangled with the business logic of the application, making the code hard to read and maintain. In this paper, we propose an extension of the Java type system based on communication qualifiers . These qualifiers decorate variables with information about the invocation semantics that must be used when methods are invoked on that variable. We show how communication qualifiers are used to support transparent multicast and reliable unicast invocation semantics in Java. Moreover, we introduce declarative operations to enable developers to fine-tune these communication strategies.

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

fault tolerance
group method invocation
type qualifier


Mobile arm for disabled people assistance manipulability measure for redundancy solve The addition of a mobile platform to a 6-DOF arm raises the question of the exploitation of redundancy with respect to needs. The application field concerns assistive robotics for object manipulation tasks. Works deal with the utilisability of a mobile arm, which is a complex system, by a disabled person with reduced motor and perception abilities. In this paper, we present the influence of mobility on manipulability measure. Manipulability is a well-established tool for motion analysis which we use as criterion in control scheme to improve the coordination of two subsystems. We propose a normalized measure to solve problems inherent to the use of different physical units and velocity limits for both components of the system, arm and mobile platform. Simulation results for a 3D positioning task are given to show the effect of nonholonomic constraint on manipulability measure.

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 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 B O

mobile manipulator
nonholonomic systems
robotized assistant


Subnetwork State Functions Define Dysregulated Subnetworks in Cancer Emerging research demonstrates the potential of protein-protein interaction (PPI) networks in uncovering the mechanistic bases of cancers, through identification of interacting proteins that are coordinately dysregulated in tumorigenic and metastatic samples. When used as features for classification, such coordinately dysregulated subnetworks improve diagnosis and prognosis of cancer considerably over single-gene markers. However, existing methods formulate coordination between multiple genes through additive representation of their expression profiles and utilize fast heuristics to identify dysregulated subnetworks, which may not be well suited to the potentially combinatorial nature of coordinate dysregulation. Here, we propose a combinatorial formulation of coordinate dysregulation and decompose the resulting objective function to cast the problem as one of identifying subnetwork state functions that are indicative of phenotype. Based on this formulation, we show that coordinate dysregulation of larger subnetworks can be bounded using simple statistics on smaller subnetworks. We then use these bounds to devise an efficient algorithm, Crane, that can search the subnetwork space more effectively than existing algorithms. Comprehensive cross-classification experiments show that subnetworks identified by Crane outperform those identified by additive algorithms in predicting metastasis of colorectal cancer (CRC).

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

combinatorial optimization
computational molecular biology
machine learning


cem: Software for Coarsened Exact Matching This program is designed to improve causal inference via a method of matching that is widely applicable in observational data and easy to understand and use (if you understand how to draw a histogram, you will understand this method). The program implements the coarsened exact matching (CEM) algorithm, described below. CEM may be used alone or in combination with any existing matching method. This algorithm, and its statistical properties, are described in Iacus, King, and Porro (2008).

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


graph based topological analysis of tessellated surfaces In this paper a graph-based method is presented which not only characterizes topological classification of the tessellated surfaces but also simultaneously generates the substantial circles or generators on the surface. Canonical polygons cannot always be mapped back to the original surface in terms of the edges of the given triangles. Hence, instead of applying canonical transformation to the initial "word", an associated graph is constructed using the unique vertices in the word. The graph is then decomposed into its constituent loops and paths. Based on the type of edges present, the loops are classified into three types. The number of loops of each type in the graph is then used for counting the rank or genus and classification of the given surface as being open or closed, orientable or non-orientable. The image of the loops and paths on the original surface give the substantial circles and arcs on the surface respectively.

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

cut lines
characterization
surface classification
computational topology
simplical complex


gathering requirements for a personal health management system Applications are being designed to make health information available to the healthcare consumer. However, little is known about the support people need in using health information. We conducted semi-structured interviews to find out how people use health information to manage the chronic illness type-2 diabetes. We found that diabetics want to be motivated to treat the disease seriously and that the patient's social network takes on additional work that is unrelated to their existing social role to support the patient's health-related activities. Based on our findings, we propose a set of formative requirements to be included in the design of a personal health management system.

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 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 B I I O


Attentiveness assessment in learning based on fuzzy logic analysis Learner attention affects learning efficiency. However, in many classes, teachers cannot assess the degree of attention of every learner. When a teacher is capable of addressing inattentive learners immediately, he can avoid situations in which learners are inattentive. Many studies have analyzed driver attentiveness by the applying of image detection technologies. If this mechanism can be applied to in-class learning, it will help teachers keep learners attentive, and reduce teacher load during class. This study mainly applies fuzzy logic analysis of learner facial images when participating in class. Two fuzzy logic algorithms are proposed to determine the level of inattention by measuring the leaving, drowsiness, head turning and no motion. Applying fuzzy logic can prevent erroneous judgments associated with a single term, and help teachers deal with learner attentiveness. The simulation works are carried to evaluate the effect of the proposed system under various conditions. The simulation results indicated that the proposed system is effective for detecting of learner attentiveness in class.

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 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 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

learner attention analysis
image processing


Context-aware adaptive data stream mining In resource-constrained devices, adaptation of data stream processing to variations of data rates and availability of resources is crucial for consistency and continuity of running applications. However, to enhance and maximize the benefits of adaptation, there is a need to go beyond mere computational and device capabilities to encompass the full spectrum of context-awareness. This paper presents a general approach for context-aware adaptive mining of data streams that aims to dynamically and autonomously adjust data stream mining parameters according to changes in context and situations. We perform intelligent and real-time analysis of data streams generated from sensors that is under-pinned using context-aware adaptation. A prototype of the proposed architecture is implemented and evaluated in the paper through a real-world scenario in the area of healthcare monitoring.

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


Mixed variable structural optimization using Firefly Algorithm In this study, a recently developed metaheuristic optimization algorithm, the Firefly Algorithm (FA), is used for solving mixed continuous/discrete structural optimization problems. FA mimics the social behavior of fireflies based on their flashing characteristics. The results of a trade study carried out on six classical structural optimization problems taken from literature confirm the validity of the proposed algorithm. The unique search features implemented in FA are analyzed, and their implications for future research work are discussed in detail in the paper.

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

metaheuristic optimization
firefly algorithm
structural optimization

mixed continuous-discrete variable problems


Semantic Web Services and Mobile Agents integration for efficient mobile services The requirement for ubiquitous service access in wireless environments presents a great challenge in light of well-known problems like high error rate and frequent disconnections. In order to satisfy this requirement, we propose the integration of two modern service technologies: Web Services and Mobile Agents. This integration allows wireless users to access and invoke semantically enriched Web Services without the need for simultaneous, online presence of the service requestor Moreover, in order to improve the capabilities offered by the Semantic Web framework. Specifically, we use Service registries, we exploit the advantages of enhanced registries enriched with semantic information that provide semantic matching to service queries and published service descriptions. Finally, we discuss the implementation of the proposed framework and present our performance assessment findings.

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

mobile agents
mobile services
semantic web

distributed computing
ontologies
semantic web services


A novel case adaptation method based on an improved integrated genetic algorithm for power grid wind disaster emergencies We proposed a novel case adaptation method for wind disaster emergency of power grid. This method improved adaptive multi-objective genetic algorithm in performance. We improved frame theory in incomplete information with evidence theory. This method could be chose as a new method for expanding case base.

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

case adaptation
wind disaster emergencies

case-based reasoning
grey relational analysis
multi-objective genetic algorithms
d/s evidence theory


Keystroke dynamics-based user authentication using long and free text strings from various input devices Keystroke dynamics, which refers to the typing pattern of an individual, has been highlighted as a practical behavioral biometric feature that does not require any additional recognition device for strengthening user authentication or identification. However, research in the area of keystroke dynamics-based user authentication (KDA) has been primarily focused only on the short predefined text, such as identification (ID) and password, typed on a traditional personal computer (PC) keyboard. In this paper, we aim to explore the extendability of KDA by considering long and free text strings from various input devices. Three fundamental questions are raised about the dependence of authentication performance on (1) the type of input device, (2) the length of text strings, and (3) the type of authentication algorithm. Based on the experimental tests, we observe that (1) the usage of a PC keyboard reported the highest authentication accuracy, followed by a soft keyboard and a touch keyboard; (2) the authentication accuracy could be strengthened by increasing the length of either reference or test keystrokes; (3) the R+A and RA measures report the best performance with a PC keyboard, while the Cramrvon Mises criterion reports the best performance with the other input devices for most cases, followed by the Parzen window density estimator.

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

keystroke dynamics
user authentication
long and free text strings
various input devices
cramrvon mises criterion


Structures of XH4+ and XH6+ (X = B, Al and Ga) cations Structures and energies of XH4+ and XH6+ (X = B, Al and Ga) have been calculated at the density functional theory (DFT) B3LYP/6-311++G(3df,2pd) level. Calculations indicate that although the structure with a three center two electron (3c-2e) bond is the global minimum for BH4+, the global minima of AlH4+ and GaH4+ are not those with one 3c-2e bond, but those with two 3c-2e bonds. For calibration, both structures of AlH4+ were also calculated at the ab initio CCSD(T)/cc-pVTZ level and results in agreement with the DFT results were found. Similar calculations also indicate that although the C-2v symmetrical structure with two 3c-2e bonds is the global minimum for BH6+, the global minima of AlH6+ and GaH6+ are not the C-2v symmetrical structures with two 3c-2e bonds but the C-2 symmetrical structures with three 3c-2e bonds.

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

density functional calculations
boronium ion
three center two electron bond


Assessing the quality of geoscientific simulation models with visual analytics methods - a design study Simulation models are essential means of scientific knowledge building and also the basis for decision-making. Because of their relevance, they have to be assessed thoroughly with respect to their quality. Simulation model assessment comprises two challenges: (a) modelers have to create a comprehensive mental image of the model's quality despite the massive multidimensional, multivariate, and often heterogeneous data; and (b) the model assessment process should be as efficient as possible. We face these challenges with a visual analytics approach. We aim at developing interactive visual representations which, in combination with present computational analysis methods, support the scientist's reasoning process to enhance the assessment of simulation models. In a design study, we analyzed two exemplary reasoning processes which cover the main model assessment procedures: the evaluation of the internal coherence of the model's structure and behavior and the assessment of its empirical validity. The analysis was conducted by means of a user- and task-centered approach which combines several knowledge elicitation techniques and task analysis concepts. We derived domain tasks as well as cognitive actions and developed and implemented interactive visualization components which supplement the statistical analysis methods already used. An informal qualitative user study shows that our visual analytics approach and tools help gain a more detailed mental image and hence a better understanding of the data and the underlying simulation model and allow for a faster and more comprehensive assessment of the simulation model.

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

task analysis
model assessment
reasoning


Weighted least squares support vector machines: robustness and sparse approximation ? Least squares support vector machines (LS-SVM) is an SVM version which involves equality instead of inequality constraints and works with a least squares cost function. In this way, the solution follows from a linear KarushKuhnTucker system instead of a quadratic programming problem. However, sparseness is lost in the LS-SVM case and the estimation of the support values is only optimal in the case of a Gaussian distribution of the error variables. In this paper, we discuss a method which can overcome these two drawbacks. We show how to obtain robust estimates for regression by applying a weighted version of LS-SVM. We also discuss a sparse approximation procedure for weighted and unweighted LS-SVM. It is basically a pruning method which is able to do pruning based upon the physical meaning of the sorted support values, while pruning procedures for classical multilayer perceptrons require the computation of a Hessian matrix or its inverse. The methods of this paper are illustrated for RBF kernels and demonstrate how to obtain robust estimates with selection of an appropriate number of hidden units, in the case of outliers or non-Gaussian error distributions with heavy tails.

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

support vector machines
sparse approximation

(weighted) least squares
ridge regression
robust estimation


Polaronic effects on the collective excitation energies in a quantum wire In this work we report a investigation of the plasmonlongitudinal-optical (LO) phonon interaction effects on the intersubband and intrasubband collective excitation energies in a GaAsAl?Ga1??As rectangular quantum well wire. We observe a resonant split of the collective excitation energy into two branches, one with energy lower and other with energy higher than the LO-optical phonon energy ??LO. Our calculations are performed using a self-consistent field approximation, which includes the local-field correction within the Singwi, Tosi, Land, and Sjolander (STLS) theory at zero temperature and assuming a three-subband model, where only the first subband is occupied by electrons. The potential confining effects on the collective energies were also considered.

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

longitudinal optical phonon
plasmon
gaasalgaas quantum wire


Social informatics and sociotechnical research - a view from the UK This paper explores the connections between two historical lines of research: social informatics in the United States, and sociotechnical studies in the United Kingdom. The author discusses samples of work from three long established UK research sites, at Manchester, Edinburgh and the London School of Economics, to give the reader a sense of sociotechnical work at different historical periods. Though the US and UK traditions share a common interest in the production of technology, and work with complementary concepts and methods, formal links between the two have not been strong for much of the historical period under review. However, there are signs of fusion in the work of a current generation of researchers on both sides of the Atlantic.

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 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

social informatics
sociotechnical studies

truth spots
participatory design
social shaping of technology
critical is


Optimal design of passive power filters based on multi-objective bat algorithm and pareto front Four typical types of passive power filter. Four objectives and five constraints. Modified bat algorithm using inertia weight and external archive for multi-objective optimization.

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 B I O O O O B I O O O

bat algorithm
external archive
passive power filters

multi-objective optimization
non-dominated solutions


Sparse episode identification in environmental datasets: The case of air quality assessment Sparse episode identification in environmental datasets is not only a multi-faceted and computationally challenging problem for machine learning algorithms, but also a difficult task for human-decision makers: the strict regulatory framework, in combination with the public demand for better information services, poses the need for robust, efficient and, more importantly, understandable forecasting models. Additionally, these models need to provide decision-makers with summarized and valuable knowledge, that has to be subjected to a thorough evaluation procedure, easily translated to services and/or actions in actual decision making situations, and integratable with existing Environmental Management Systems (EMSs). On this basis, our current study investigates the potential of various machine learning algorithms as tools for air quality (AQ) episode forecasting and assesses them given the corresponding domain-specific requirements using an evaluation procedure, tailored to the task at hand. Among the algorithms employed in the experimental phase, our main focus is on ZCS-DM, an evolutionary rule-induction algorithm specifically designed to tackle this class of problems that is classification problems with skewed class distributions, where cost-sensitive model building is required. Overall, we consider this investigation successful, in terms of its aforementioned goals and constraints: obtained experimental results reveal the potential of rule-based algorithms for urban AQ forecasting, and point towards ZCS-DM as the most suitable algorithm for the target domain, providing the best trade-off between model performance and understandability.

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

air quality (aq)
domain-driven data mining
model evaluation


Synthesis of dynamic motions for robotic manipulators with geometric path constraints This paper presents a new method to plan minimum cost movements for non-redundant robotic manipulators along prescribed geometric paths while tacking into account various kinodynamic constraints. The problem consists of defining the best way to follow a prescribed geometric path under several constraints, such as limitations on joint torque, jerk, acceleration or velocity, while minimizing an objective function (time transfer, mean average of joint torques, etc.). It is formulated as a non-linear optimization problem and can be then treated by any adequate mathematical optimization method. Numerical examples using genetic algorithms are presented to illustrate the effectiveness of the proposed approach. (C) 2006 Elsevier Ltd. All rights reserved.

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


Mediating the expression of emotion in educational collaborative virtual environments: an experimental study The use of avatars with emotionally expressive faces is potentially highly beneficial to communication in collaborative virtual environments (CVEs), especially when used in a distance learning context. However, little is known about how, or indeed whether, emotions can effectively be transmitted through the medium of a CVE. Given this, an avatar head model with limited but human-like expressive abilities was built, designed to enrich CVE communication. Based on the facial action coding system (FACS), the head was designed to express, in a readily recognisable manner, the six universal emotions. An experiment was conducted to investigate the efficacy of the model. Results indicate that the approach of applying the FACS model to virtual face representations is not guaranteed to work for all expressions of a particular emotion category. However, given appropriate use of the model, emotions can effectively be visualised with a limited number of facial features. A set of exemplar facial expressions is presented.

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

collaborative virtual environment
facial expression


Distribution-free connectivity testing for sparse graphs We consider distribution-free property-testing of graph connectivity. In this setting of property testing, the distance between functions is measured with respect to a fixed but unknown distribution D on the domain, and the testing algorithm has an oracle access to random sampling from the domain according to this distribution D. This notion of distribution-free testing was previously defined, and testers were shown for very few properties. However, no distribution-free property testing algorithm was known for any graph property. We present the first distribution-free testing algorithms for one of the central properties in this area-graph connectivity (specifically, the problem is mainly interesting in the case of sparse graphs). We introduce three testing models for sparse graphs: A model for bounded-degree graphs, A model for graphs with a bound on the total number of edges (both models were already considered in the context of uniform distribution testing), and A model which is a combination of the two previous testing models; i.e., bounded-degree graphs with a bound on the total number of edges.

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 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

distribution-free testing
properties of sparse graphs


Energy-aware preemptive scheduling algorithm for sporadic tasks on DVS platform Dynamic Voltage Scaling (DVS) is a key technique for embedded systems to exploit multiple voltage and frequency levels to reduce energy consumption and to extend battery life. There are many DVS-based algorithms proposed for periodic and aperiodic task models. However, there are few algorithms that support the sporadic task model. Moreover, existing algorithms that support the sporadic model lack of functionalities in terms of energy-saving. In this paper, we propose a novel energy-aware scheduling algorithm named Cycle Conserve Dynamic Voltage Scaling for Sporadic Tasks (CC-DVSST) algorithm which is an improvement to DVSST [1]. There is a large amount of time slack in the DVSST scheduling due to the significant difference between the actual execution time and the worst-case scenario. Introducing DVS with EDF, CC-DVSST scales down the voltage of a processor when tasks are completed earlier than they are expected, so that the slack time can be reused for other tasks, hence saving energy. Experimental results show that CC-DVSST can reduce the total amount of energy consumption up to 46% compared to DVSST while retaining the quality of service by meeting the deadlines.

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

preemptive scheduling
sporadic tasks
embedded systems
dvs

energy conservation
real-time
uniprocessor


The efieldbook program: A teaching resource for geology The eFieldBook program is a geology teaching tool with high didactic potential that guides a student's work in the field using multimedia and other resources. This program allows the collection of geo-referenced geological information as well as its storage and transmission, if necessary, as soon as it is collected. The data can be collected as in traditional field notebooks or on maps and photographs. The information can be used as soon as it is collected and can be exported to other programs such as Word, Excel, Georient or statistical packages. eFieldBook safely stores and backs up user information by sending any data collected to a selected Internet target at regular time intervals. (C) 2010 Elsevier Ltd. All rights reserved.

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

field book
digital field mapping
geology learning tool
computer learning
gps


Cognitive visual tracking and camera control Cognitive visual tracking is the process of observing and understanding the behavior of a moving person. This paper presents an efficient solution to extract, in real-time, high-level information from an observed scene, and generate the most appropriate commands for a set of pan-tilt-zoom (PTZ) cameras in a surveillance scenario. Such a high-level feedback control loop, which is the main novelty of our work, will serve to reduce uncertainties in the observed scene and to maximize the amount of information extracted from it. It is implemented with a distributed camera system using SQL tables as virtual communication channels, and Situation Graph Trees for knowledge representation, inference and high-level camera control. A set of experiments in a surveillance scenario show the effectiveness of our approach and its potential for real applications of cognitive vision.

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


Sitstand desks in call centres: Associations of use and ergonomics awareness with sedentary behavior To investigate whether or not use of sitstand desks and awareness of the importance of postural variation and breaks are associated with the pattern of sedentary behavior in office workers. The data came from a cross-sectional observation study of Swedish call centre workers. Inclinometers recorded seated or standing/walking episodes of 131 operators over a full work shift. Differences in sedentary behavior based on desk type and awareness of the importance of posture variation and breaks were assessed by non-parametric analyses. 90 (68.7%) operators worked at a sitstand desk. Working at a sitstand desk, as opposed to a sit desk, was associated with less time seated (78.5 vs 83.8%, p=0.010), and less time taken to accumulate 5min of standing/walking (36.2 vs 46.3min, p=0.022), but no significant difference to sitting episode length or the number of switches between sitting and standing/walking per hour. Ergonomics awareness was not associated with any sedentary pattern variable among those using a sitstand desk. Use of sitstand desks was associated with better sedentary behavior in call centre workers, however ergonomics awareness did not enhance the effect.

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

sedentary behavior
posture
call centres
ergonomics awareness


Performance characterization of a rover navigation algorithm using large-scale simulation Autonomous rover navigation is a critical technology for robotic exploration of Mars. Simulation allows more extensive testing of such technologies than would be possible with hardware test beds alone. A large number of simulations, running in parallel, can test an algorithm under many different operating conditions to quickly identify the operational envelope of the technology and identify failure modes that were not discovered in more limited testing. GESTALT is the autonomous navigation algorithm developed for NASA's Mars rovers. ROAMS is a rover simulator developed to support the Mars program. We have integrated GESTALT into ROAMS to test closed-loop, autonomous navigation in simulation. We have developed a prototype capability to run many copies of ROAMS in parallel on a supercomputer, varying input parameters to rapidly explore GESTALT's performance across a parameter space. Using these tools, we have demonstrated that large scale simulation can identify performance limits and unexpected behaviors in an algorithm. Such parallel simulation was able to test approximately 500 parameter combinations in the time required for a single test on a hardware test bed.

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


Theoretical study of the novel sandwich compound [Au3Cl3Tr2](2+) A theoretical study of a sandwich compound with a metal monolayer sheet between two aromatic ligands is presented. A full geometry optimization of the [Au3Cl3Tr2](2+) (1) compound, which is a triangular gold(I) monolayer sheet capped by chlorines and bounded to two cycloheptatrienyl (Tr) ligands was carried out using perturbation theory at the MP2 computational level and DFT. Compound (1) is in agreement with the 18-electron rule, the bonding nature in the complex may be interpreted from the donation interaction coming from the Tr rings to the Au array, and from the back-donation from the latter to the former. NICS calculations show a strong aromatic character in the gold monolayer sheet and Tr ligands; calculations done with HOMA, also report the same aromatic behavior on the cycloheptatrienyl fragments giving us an insight on the stability of (1). The Au -Au bond lengths indicate that an intramolecular aurophilic interaction among the Au(I) cations plays an important role in the bonding of the central metal sheet.

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


A self-stabilizing algorithm for the shortest path problem assuming the distributed demon Shortest path finding has a variety of applications in transportation and communication. In this paper, we study a well-known self-stabilizing algorithm for the shortest path problem for the distributed systems. The previous works on this topic had two assumptions that can be relaxed in this paper. First, in the previous works, the systems were assumed to be integral-weighted, whereas in this paper, the systems are real-weighted. Second, and more importantly, the previous works have shown that the algorithm is self-stabilizing under the more restricted central demon model, whereas in this paper, we give a rigorous proof showing that the algorithm is actually self-stabilizing under the more general distributed demon model. The work in this paper is of significance because in the existing literature on self-stabilizing systems, most of the papers regarding the distributed demon are for the ring networks only; there are very few papers that discuss the self-stabilizing algorithms for the general distributed systems assuming the distributed demon model. (c) 2005 Elsevier Ltd. All rights reserved.

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

real-weighted system
bounded function technique
self-stabilizing algorithm


Elastic Tubes: Modeling Elastic Deformation of Hollow Tubes The Cosserat theory of elastic rods has been used in a wide range of application domains to model and simulate the elastic deformation of thin rods. It is physically accurate and its implementations are efficient for interactive simulation. However, one requirement of using Cosserat rod theory is that the tubular object must have rigid cross-sections that are small compared to its length. This requirement make it difficult for the approach to model elastic deformation of rods with large, non-rigid cross-sections that can change shape during rod deformation, in particular, hollow tubes. Our approach achieves this task using a hybrid model that binds a mesh elastically to a reference Cosserat rod. The mesh represents the surface of the hollow tube while the reference rod models bending, twisting, shearing and stretching of the tube. The cross-sections of the tube may take on any arbitrary shape. The binding is established by a mapping between mesh vertices and the rod's directors. Deformation of the elastic tube is accomplished in two phases. First, the reference rod is deformed according to Cosserat theory. Next, the mesh is deformed using Laplacian deformation according to its mapping to the rod and its surface elastic energy. This hybrid approach allows the tube to deform in a physically correct manner in relation to the bending, twisting, shearing, and stretching of the reference rod. It also allows the surface to deform realistically and efficiently according to surface elastic energy and the shape of the reference rod. In this way, the deformation of elastic hollow tubes with large, non-rigid cross-sections can be simulated accurately and efficiently.

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

elastic tubes
cosserat rod theory
laplacian deformation


IPO: a tool for automated optimization of XCMS parameters Untargeted metabolomics generates a huge amount of data. Software packages for automated data processing are crucial to successfully process these data. A variety of such software packages exist, but the outcome of data processing strongly depends on algorithm parameter settings. If they are not carefully chosen, suboptimal parameter settings can easily lead to biased results. Therefore, parameter settings also require optimization. Several parameter optimization approaches have already been proposed, but a software package for parameter optimization which is free of intricate experimental labeling steps, fast and widely applicable is still missing.

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

metabolomics
xcms
parameter optimization


Fault-tolerant meshes with constant degree This paper proves that for every positive integers n,k and any positive number epsilon, we can explicitly construct a DAG G with n+O(k(1+epsilon)) vertices and a constant degree such that even after removing any k vertices from G, the remaining digraph still contains an n-vertex dipath. This paper also proves that for every positive integers n, k and any positive number epsilon, we can explicitly construct a graph H with n + O(k(2+epsilon)) vertices and a constant degree such that even after removing any k vertices from H, the remaining graph still contains an n-vertex 2-dimensional square mesh. key words: fault-tolerant graph, dipath, mesh, tower graph, constant degree

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


A one-shot domain-independent robust multimedia clustering methodology based on hybrid multimodal fusion The existence of multiple modalities poses a challenge to the design of multimedia data clustering systems, as the unsupervised nature of the problem makes it very difficult to determine a priori whether a single modality should dominate the clustering process, or if modalities should be combined somehow. In order to fight against these indeterminacieswhich come on top of those referring to the selection of the optimal clustering algorithm and data representation for the problem at hand, this work introduces robust multimedia clustering, a one-shot methodology for domain independent multimedia data clustering based on hybrid multimodal fusion. By means of experimentation, we firstly justify the motivation of the proposed methodology by proving the relevance of multimedia clustering indeterminacies. Subsequently, a specific multimedia clustering system based on the requirements of the methodology is implemented and evaluated on three multimedia clustering applicationsmusic genres, photographic topics and audio-visual objects classificationas a proof of concept, analyzing the quality of the obtained partitions and the time complexity of the proposal. The experimental results reveal that the implemented system, which includes a self-refining consensus clustering procedure for attaining high levels of robustness, allows to obtain, in a fully unsupervised manner, better quality partitions than 93% of the clusterers available in our experiments, being even able to improve the quality of the best ones and outperforming state-of-the-art alternatives.

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

robust multimedia clustering
hybrid multimodal fusion
clustering indeterminacies

cluster ensembles
self-refining consensus


Connectomic constraints on computation in feedforward networks of spiking neurons Several efforts are currently underway to decipher the connectome or parts thereof in a variety of organisms. Ascertaining the detailed physiological properties of all the neurons in these connectomes, however, is out of the scope of such projects. It is therefore unclear to what extent knowledge of the connectome alone will advance a mechanistic understanding of computation occurring in these neural circuits, especially when the high-level function of the said circuit is unknown. We consider, here, the question of how the wiring diagram of neurons imposes constraints on what neural circuits can compute, when we cannot assume detailed information on the physiological response properties of the neurons. We call such constraintsthat arise by virtue of the connectomeconnectomic constraints on computation. For feedforward networks equipped with neurons that obey a deterministic spiking neuron model which satisfies a small number of properties, we ask if just by knowing the architecture of a network, we can rule out computations that it could be doing, no matter what response properties each of its neurons may have. We show results of this form, for certain classes of network architectures. On the other hand, we also prove that with the limited set of properties assumed for our model neurons, there are fundamental limits to the constraints imposed by network structure. Thus, our theory suggests that while connectomic constraints might restrict the computational ability of certain classes of network architectures, we may require more elaborate information on the properties of neurons in the network, before we can discern such results for other classes of networks.

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


a static partitioning and mapping algorithm for conservative parallel simulations In this paper, we consider the problem of partitioning a conservative parallel simulation for execution on a multi-computer. The synchronization protocol makes use of null messages [6]. We propose the use of a simulated annealing algorithm with an adaptive search schedule to find good (sub-optimal) partitions. The paper discusses the algorithm, its implementation and reports on the performance results of simulations of a partitioned FCFS queueing network model executed on iPSC/860 hypercube. The results obtained are compared with a random partitioning. They show that a partitioning which makes use of our simulated annealing algorithm results in a reduction of 25-35\% of the running time of the simulations when compared to the running time of a random partition of the model.

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

use
simulation
synchronization
performance
reduction
simulated annealing
model
paper
search
partition
parallel
implementation
algorithm
hypercube

scheduling
parallel simulation
computation
map
queue
timing
randomization
adapt
optimality
message
network model


A fast Hermite transform We present algorithms for fast and stable approximation of the Hermite transform of a compactly supported function on the real line, attainable via an application of a fast algebraic algorithm for computing sums associated with a three-term relation. Tradeoffs between approximation in bandlimit (in the Hermite sense), and size of the support region are addressed. Numerical experiments are presented that show the feasibility and utility of our approach. Generalizations to any family of orthogonal polynomials are outlined. Applications to various problems in tomographic reconstruction, including the determination of protein structure, are discussed. (C) 2008 Elsevier B.V. All rights reserved.

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

hermite transform
tomographic reconstruction
protein structure

generalized fourier transform
orthogonal polynomial transform
three-term recurrence


Hierarchical attentive multiple models for execution and recognition of actions According to the motor theories of perception, the motor systems of an observer are actively involved in the perception of actions when these are performed by a demonstrator. In this paper we review our computational architecture, HAMMER (Hierarchical Attentive Multiple Models for Execution and Recognition), where the motor control systems of a robot are organised in a hierarchical, distributed manner, and can be used in the dual role of (a) competitively selecting and executing an action, and (b) perceiving it when performed by a demonstrator. We subsequently demonstrate that such an arrangement can provide a principled method for the top-down control of attention during action perception, resulting in significant performance gains. We assess these performance gains under a variety of resource allocation strategies.

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

imitation
hierarchical structures
action recognition


creating and evaluating a video vocabulary for communicating verbs for different age groups Icons and digital images used in augmentative and alternative communication (AAC) are not as effective in illustrating verbs, especially for people with cognitive degeneration or impairment. Realistic videos have possible advantages for conveying verbs, as verified in our studies with young and old adults comparing single image, multiple images, animations, and video clips. Videos are especially more effective for verbs that show concrete movements or actions. Based on our studies, we propose rules for filming video verb representations, exploring possible visual cues and other factors that may affect people's perception and interpretation.

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


Numerical study of flow uniformity and pressure characteristics within a microchannel array with triangular manifolds Flow uniformity among individual channels within a microchannel array can be a significant factor affecting the performance of laminated structured micro-devices. In this study, numerical modeling is used to quantitatively investigate the impact of the geometry of the right triangular manifold and the dimensions of microchannels on desired uniformity and pressure drop. The CFD tool COMSOL is used to perform the simulations within the low-Reynolds number system (5 <= Re <= 25). In our biomedical application, it is important to have low dead volume and residence time in the manifolds. A methodical approach is introduced to identify a design that balances low manifold volume and maintenance of flow uniformity. It has also been shown that including a short vertical spacing at the corner of manifolds is critical to achieving a high level of flow uniformity. Careful analysis and physical interpretation of trends herein enables a more intuitive approach to array design. (C) 2013 Elsevier Ltd. All rights reserved.

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

uniform flow distribution
computational fluid dynamics (cfd)


Clustering Based on Enhanced alpha-Expansion Move The exemplar-based data clustering problem can be formulated as minimizing an energy function defined on a Markov random field (MRF). However, most algorithms for optimizing the MRF energy function cannot be directly applied to the task of clustering, as the problem has a high-order energy function. In this paper, we first show that the high-order energy function for the clustering problem can be simplified as a pairwise energy function with the metric property, and consequently it can be optimized by the alpha-expansion move algorithm based on graph cut. Then, the original expansion move algorithm is improved in the following two aspects: 1) Instead of solving a minimal s-t graph cut problem, we show that there is an explicit and interpretable solution for minimizing the energy function in the clustering problem. Based on this interpretation, a fast alpha-expansion move algorithm is proposed, which is much more efficient than the graph-cut-based algorithm. 2) The fast alpha-expansion move algorithm is further improved by extending its move space so that a larger energy value reduction can be achieved in each iteration. Experiments on benchmark data sets show that the enhanced expansion move algorithm has a better performance, compared to other state-of-the-art exemplar-based clustering 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 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 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


GAMETES: a fast, direct algorithm for generating pure, strict, epistatic models with random architectures Geneticists who look beyond single locus disease associations require additional strategies for the detection of complex multi-locus effects. Epistasis, a multi-locus masking effect, presents a particular challenge, and has been the target of bioinformatic development. Thorough evaluation of new algorithms calls for simulation studies in which known disease models are sought. To date, the best methods for generating simulated multi-locus epistatic models rely on genetic algorithms. However, such methods are computationally expensive, difficult to adapt to multiple objectives, and unlikely to yield models with a precise form of epistasis which we refer to as pure and strict. Purely and strictly epistatic models constitute the worst-case in terms of detecting disease associations, since such associations may only be observed if all n-loci are included in the disease model. This makes them an attractive gold standard for simulation studies considering complex multi-locus effects.

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


Nets of small degree without ovals We construct r-nets of many different orders which have no ovals and r-nets of many other orders which have no hyperovals.

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

net
projective plane
desarguesian
oval
hyperoval


Cross-entropic comparison of formants of British, Australian and American English accents This paper highlights the differences in spectral features between British, Australian and American English accents and applies the cross-entropy information measure for comparative quantification of the impacts of the variations of accents, speaker groups and recordings on the probability models of spectral features of phonetic units of speech. Comparison of the cross-entropies of formants and cepstrum features indicates that formants are a better indicator of accents. In particular it appears that the measurements of differences in formants across accents are less sensitive to different recordings or databases compared to cepstrum features. It is found that the cross-entropies of the same phonemes across speaker groups with different accents (inter-accent distances) are significantly greater than the cross-entropies of the same phonemes across speaker groups of the same accent (intra-accent distances). Comparative evaluations presented on cross-gender speech recognition shows that accent differences have an impact comparable to gender differences. The cross-entropy measure is also used to construct cross-accent phonetic-trees, which serve to show the structural similarities and differences of the phonetic systems across accents.

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

cross-entropy
formant features
formant space


Numerical study of quantum transport in carbon nanotube transistors A deeper understanding of quantum effects in nano-electronic devices helps to improve the functionality and to develop new device types. The performance of carbon nanotube (CNT) field-effect transistor is studied using the non-equilibrium Green's function (NEGF) formalism. The effects of elastic and inelastic scattering and the impact of parameters, such as electron-phonon coupling strength and phonon energy, on the device performance are analyzed. (C) 2007 IMACS. Published by Elsevier B.V. All rights reserved.

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


Video Streaming Distribution in VANETs Streaming applications will rapidly develop and contribute a significant amount of traffic in the near future. A problem, scarcely addressed so far, is how to distribute video streaming traffic from one source to all nodes in an urban vehicular network. This problem significantly differs from previous work on broadcast and multicast in ad hoc networks because of the highly dynamic topology of vehicular networks and the strict delay requirements of streaming applications. We present a solution for intervehicular communications, called Streaming Urban Video (SUV), that 1) is fully distributed and dynamically adapts to topology changes, and 2) leverages the characteristics of streaming applications to yield a highly efficient, cross-layer solution.

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


Using Facial Symmetry to Handle Pose Variations in Real-World 3D Face Recognition The uncontrolled conditions of real-world biometric applications pose a great challenge to any face recognition approach. The unconstrained acquisition of data from uncooperative subjects may result in facial scans with significant pose variations along the yaw axis. Such pose variations can cause extensive occlusions, resulting in missing data. In this paper, a novel 3D face recognition method is proposed that uses facial symmetry to handle pose variations. It employs an automatic landmark detector that estimates pose and detects occluded areas for each facial scan. Subsequently, an Annotated Face Model is registered and fitted to the scan. During fitting, facial symmetry is used to overcome the challenges of missing data. The result is a pose invariant geometry image. Unlike existing methods that require frontal scans, the proposed method performs comparisons among interpose scans using a wavelet-based biometric signature. It is suitable for real-world applications as it only requires half of the face to be visible to the sensor. The proposed method was evaluated using databases from the University of Notre Dame and the University of Houston that, to the best of our knowledge, include the most challenging pose variations publicly available. The average rank-one recognition rate of the proposed method in these databases was 83.7 percent.

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

biometrics
face and gesture recognition
physically-based modeling


Development of an optical sensor for crop leaf chlorophyll content detection Nitrogen content in crop leaf is an important indication for evaluating crop health and predicting crop yield. A normalized difference vegetation index (NDVI) is widely used as an indicator in estimating leaf nitrogen content in practice. How to effectively and accurately measure the NDVI value of crop leaves in the field is a challenge on in-field use instrument development. This paper reports the development of a hand-held spectroscopy-based optical sensing device for measuring crop leaf NDVI values under in-field natural light conditions. This optical sensing device could simultaneously measure the spectral reflectance of canopies and the solar intensity at two bands of 610 and 1220nm, and calculate NDVI value in real-time based on measured spectral reflectance. This device was tested in tomato plants chlorophyll content measurement. A series of field tests were conducted to evaluate the performance of the sensor, and tomato leaf samples were collected for measuring chlorophyll contents as the reference for validation. Obtained results indicated that NDVI values measured with this sensing device had a close correlation with chlorophyll contents of the collected leaf samples measured in laboratory with a UVvis spectrophotometer ( R O p t 2 = 0.66 ) .

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

crop leaf nitrogen content
in-field ndvi measurement
hand-held instrument
lower cost design