A new quadrilateral shell element using 16 degrees of freedom Purpose - The purpose of this paper is to present a quadrilateral shell element using 16 degrees offreedom (dof) (12 translations and four rotations) which makes a pair with Morley's triangle at 12 dof This latter has been updated by Batoz who later proposed an extension to a quadrilateral ("DKQ16") but only with special interpolation functions for an elastic behaviour of the material. Precisely, it is in order to release from this strong limitation that a completely different formulation is proposed here. Design/methodology/approach - The development of this new quadrilateral called "DKS16" involves three stages. The first one starts from Morley's triangle updated by Batoz ("DKT12") to derive a rotation-free (RF) triangular element ("S3"). The second stage consists in generalising this triangle to a RF quadrilateral ("S4"). During the final leg, the S4 and DKT12 main features are combined to give the quadrilateral "DKS16". Findings - Other parameters being equal, the type of finite element chosen for the forming stage simulation has a great influence on further springback result even in software with automatic remeshing. Particularly, it is pointed out that the RF shell elements S3 and S4 as well as the triangle DKT12 are less sensitive to the mesh size than classical shell elements with six dof per node. But, even if some improvements of in-plane shear have been proposed, stamping codes users are reluctant to use triangles. That is why this paper presents an attempt to extrapolate a quadrilateral (DKS16) from the triangle DKT12 via S3 and S4 elements formulation. Numerous examples showing convergence and accuracy are presented: irregular meshes, large displacement analyses and deep-drawing simulations. Practical implications - The triangular "S3" element is already implemented in RADIOSS (R) software and its implementation - as well as the one of "DKT12" - is in progress in Pam-Stamp, both as "user elements". The next step will be the implementation of the quadrilateral "S4" (RF) and, maybe, the element "DKS16" since both are cheaper in terms of computation time and are found interesting for sheet forming. Originality/value - It seems obvious that curvatures are more exactly captured in RF elements (when nodes slide on die radius) since they are imposed in terms of translations instead of traditional nodal rotations not managed by contact conditions. As the neighbours are involved, a drawback of these RF elements is their complex formulation in case of branching surfaces and/or abrupt variations in material behaviour and/or thickness. This is not the case for elements such as DKT12 or DKS16, good candidates to add to the (long) list of cheap shell elements for large scale computations typical of sheet metal forming.

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


Optimal placement of multicast and wavelength converting nodes in multicast optical virtual private network This paper addresses multicast-nodes (MC-nodes) and wavelength converting-nodes (WC-nodes) placement problem in multicast optical virtual private network (M-OVPN). This problem is motivated by the high cost incurred in the usage of optical splitters and converters in the VPN due to complexity and power considerations. An analytical model for computing the approximate blocking probability in M-OVPN with wavelength conversion has been developed. The placement of both MC-nodes and WC-nodes is determined using our proposed innovative Removal algorithm together with the blocking performance computed. We perform simulation studies of our algorithms using NSFNET as the network topology. The results show that the Removal heuristic is able to locate the optimal placement location within a much shorter time and with higher efficiency compared to existing heuristic. In addition, we also show the flexibility of the heuristics by introducing the hybrid (Combined Removal) and dual (Concurrent Removal) removal mode. (c) 2006 Elsevier B.V. All rights reserved.

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 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 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

virtual private network
wavelength conversion


designing tangible artefacts for playful interactions and dialogues This paper reports on the design process and iterative development of two tangible artefacts that aim to encourage and explore playful interactions and dialogues between grandchildren and grandparents living at separate locations. These designed prototypes respond to the Magic Box which is a cultural probe specifically created to explore playful activity at-a-distance in a non-electronic way. This paper reports on the process of project definition, technical design requirements, scenario creation and iterative prototype development. We interpret the ethnographic data from the Magic Box research; we develop activity scenarios to describe potential activities; and we design and develop working interaction prototypes to be tested in the field in future studies.

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

intergenerational communication
interaction design
phatic technologies
ludic activity
playful interaction


Analytical validation of the BEMapplication of the BEM to the electrocardiographic forward and inverse problem The objective of this study is to analytically validate a boundary element (BE) formulation for the relationship between the transmembrane potential on the heart's surface and the potential on the body surface applying a concentric spherical test geometry. The relative difference (reldif) between the potential on the outer sphere of the test geometry computed analytically and numerically is determined by 3.59% for the coarse discretization (48 BEs) and by 0.46% in the case of the finer subdivision (192 BEs). In the inverse problem, the transmembrane potential on the inner sphere is estimated numerically from the electric potential on the outer sphere by using a minimum-norm least-square approach. The relative differences found are 20.2% when no measurement noise is added and 26.4% in the presence of 2% additional Gaussian noise. The BE formulation is also applied to real world data for solving the electrocardiographic inverse problem. A normal volunteer's inhomogeneous thorax (outer thorax surface, surfaces of the lungs, epicardial heart surface) is modelled by 424 BEs. The same inverse method is then applied in order to reconstruct the transmembrane potential on the epicardium from the measured body surface potential (BSP) data during normal ventricular depolarisation.

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


Reliable Anchor-Based Sensor Localization in Irregular Areas Localization is a fundamental problem in wireless sensor networks and its accuracy impacts the efficiency of location-aware protocols and applications, such as routing and storage. Most previous localization algorithms assume that sensors are distributed in regular areas without holes or obstacles, which often does not reflect real-world conditions, especially for outdoor deployment of wireless sensor networks. In this paper, we propose a novel scheme called Reliable Anchor-based Localization (RAL), which can greatly reduce the localization error due to the irregular deployment areas. We first provide theoretical analysis of the minimum hop length for uniformly distributed networks and then show its close approximation to empirical results, which can assist in the construction of a reliable minimal hop-length table offline. Using this table, we are able to tell whether a path is severely detoured and compute a more accurate average hop length as the basis for distance estimation. At runtime, the RAL scheme 1) utilizes the reliable minimal hop length from the table as the threshold to differentiate between reliable anchors and unreliable ones, and 2) allows each sensor to determine its position utilizing only distance constraints obtained from reliable anchors. The simulation results show that RAL can effectively filter out unreliable anchors and therefore improve the localization accuracy.

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 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


SEMANTIC MAPPING FROM NATURAL LANGUAGE QUESTIONS TO OWL QUERIES Natural language question-and-answering is one of the most convenient means for communicating with the Semantic Web, which is typically in the form of online knowledge bases encoded in Web Ontology Language (OWL). To understand a natural language question, it is essential that it can be translated into a query that is understandable by the knowledge bases. This article is concerned with the task of semantic mapping from natural language questions to OWL queries, and proposes an automatic and domain-independent mapping framework, called Three-Phases Semantic Mapping (TPSM). The TPSM framework approaches the task of semantic mapping in three interrelated phases: (i) formalizing knowledge, (ii) building semantic mapping, and (iii) combining OWL queries. First, formalizing knowledge formalizes the units of mapping in the natural language and OWL knowledge. Second, semantic mapping builds the transverse mapping between questions and OWL knowledge, as formalized in the first phase, by means of working with the so-called Fuzzy Constraint Satisfaction Problems (FCSP). Third, combining OWL queries obtains valid Resource Description Framework (RDF) models by applying predefined templates and their corresponding combining methods. We have implemented a prototype semantic mapping system based on the framework, and have conducted a series of experimental validations involving OWL knowledge bases in different domains as queried by various types of questions.

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

natural language question-and-answering
fuzzy constraint satisfaction problem


Mesoscopic study of concrete II: nonlinear finite element analysis At mesoscopic scale, concrete may be regarded as a three-phase composite consisting of coarse aggregate, mortar matrix and interfacial zones. Its composite behavior can be studied by generating a random aggregate structure which resembles the mesoscopic structure of concrete and analyzing the interaction between the three phases using the finite element method. A method of generating random aggregate structures taking into account the size, shape and spatial distributions of aggregate particles has been developed and presented in part I of the paper. Herein, a nonlinear finite element method suitable for mesoscopic study of concrete is developed. Goodman type interface elements are used to model the interfacial zones. Cracking and nonlinear constitutive properties of the materials are taken into account. A failure criterion combining tensile strength and fracture toughness is adopted. Stress relief as cracks propagate is also allowed for. An adaptive incremental displacement controlled iterative scheme which can deal with postpeak behavior is employed. The method is applied to study the strain localization of concrete under uniaxial tension in a numerical example.

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

concrete
mesoscopic study
random aggregate structure
nonlinear finite element analysis
strain localization


Desktop haptic virtual assembly using physically based modelling This research investigates the feasibility of using a desktop haptic virtual environment as a design tool for evaluating assembly operations. Bringing virtual reality characteristics to the desktop, such as stereo vision, further promotes the use of this technology into the every day engineering design process. In creating such a system, the affordability and availability of hardware/software tools is taken into consideration. The resulting application combines several software packages including VR Juggler, open dynamics engine (ODE)/open physics abstraction layer (OPAL), OpenHaptics, and OpenGL/GLM/GLUT libraries to explore the benefits and limitations of combining haptics with physically based modelling. The equipment used to display stereo graphics includes a Stereographics emitter, Crystal Eyes shutter glasses, and a high refresh rate CRT Monitor. One or two-handed force feedback is obtained from various PHANTOM haptic devices from SensAble Technologies Inc. The applications ability to handle complex part interactions is tested using two different computer systems, which approximate the higher and lower end of a typical engineers workstation. Different test scenarios are analyzed and results presented.

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 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 I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

physically based modelling
virtual reality


Inhibited spontaneous emission and electromagnetic instability of an atom in the near zone from the surface of an active medium The back reaction field and the self-consistent dynamics of a radiating dipole atom situated near a plane boundary between two isotropic media with different values of complex dielectric constants is studied. It is shown that spontaneous emission of an excited atom is suppressed, and electromagnetic instability of the ground state is possible, if an atom is located in the vicinity of an active medium which amplifies the propagating radiation. The effect is due to the modified and phase-shifted near field of an oscillating atomic dipole, which prevails over the usual radiation reaction field related to the wave zone. The role of the nonradiative energy transfer from the medium to an atom is emphasized. The necessary conditions for the reversal of the total electromagnetic back reaction are found, and possible experimental realizations of the predicted phenomena are discussed. In particular, it is argued that an atom initially in its ground state can get spontaneously excited and emit photon when going to the upper energy level.

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

spontaneous emission
electromagnetic instability

back reaction force
nonradiative transfer


Image change detection using Gaussian mixture model and genetic algorithm ? In this paper, we propose a novel method for unsupervised change detection in multi-temporal satellite images of the same scene using Gaussian mixture model (GMM) and genetic algorithm (GA). The difference image data computed from multi-temporal satellite images of the same scene is modelled by using N components GMM. GA is used to estimate the parameters of the GMM. Then, the GMM of the difference image data is partitioned into two sets of distributions representing data distributions of changed and unchanged pixels by minimizing a cost function using GA. Bayesian inference is exploited together with the estimated data distributions of changed and unchanged pixels to achieve the final change detection result. The proposed method does not need any parameter tuning process, and is completely automatic. As a case study for the unsupervised change detection, multi-temporal advanced synthetic aperture radar (ASAR) images acquired by ESA Envisat on the recent flooding area in Bangladesh and parts of India brought on by two weeks of persistent rain and multi-temporal optical images acquired by Landsat 5 TM on a part of Alaska are considered. Change detection results are shown on real data and comparisons with the state-of-the-art techniques are provided.

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

gaussian mixture model
genetic algorithm
bayesian inference
change detection
difference image
advanced synthetic aperture radar

parameter estimation
log-ratio image
remote sensing
optical image


EXISTENTIAL WITNESS EXTRACTION IN CLASSICAL REALIZABILITY AND VIA A NEGATIVE TRANSLATION We show how to extract existential witnesses from classical proofs using Krivine's classical realizability-where classical proofs are interpreted as lambda-terms with the call/cc control operator. We first recall the basic framework of classical realizability (in classical second-order arithmetic) and show how to extend it with primitive numerals for faster computations. Then we show how to perform witness extraction in this framework, by discussing several techniques depending on the shape of the existential formula. In particular, we show that in the Sigma(0)(1)-case, Krivine's witness extraction method reduces to Friedman's through a well-suited negative translation to intuitionistic second-order arithmetic. Finally we discuss the advantages of using call/cc rather than a negative translation, especially from the point of view of an implementation.

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

proof theory
classical lambda-calculus
program extraction


A Novel Communication Range Recognition (CRR) Scheme for Spatial Localization of Passive RFID Tags RFID (Radio Frequency Identification) technology is expected to be used as a localization tool. By the localization of RFID tags, a mobile robot equipped with an RFID reader can recognize the surrounding environment. In this paper, we propose a novel effective scheme called the communication range recognition (CRR) scheme for localizing RFID tags. In this scheme, an RFID reader determines the boundaries of the communication range when it is appropriately positioned by the robot. We evaluate the estimated position accuracy through numerous experiments. We show that the moving distance of the RFID reader in the proposed scheme is lower than that in conventional schemes.

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

rfid reader
localization
communication range recognition


Synchronization and stable phase-locking in a network of neurons with memory We consider a network of three identical neurons whose dynamics is governed by the Hopfield's model with delay to account for the finite switching speed of amplifiers (neurons). We show that in a certain region of the space of (alpha, beta), where alpha and beta are the normalized parameters measuring, respectively, the synaptic strength of self-connection and neighbourhood-interaction, each solution of the network is convergent to the set of synchronous states in the phase space, and this synchronization is independent of the size of the delay. We also obtain a surface; as the graph of a continuous function of tau = tau(alpha, beta) (the normalized delay) in some region of (alpha, beta), where Hopf bifurcation of periodic solutions takes place. We describe a continuous curve on such a surface where the system undergoes mode-interaction and we describe the change of patterns from stable synchronous periodic solutions to the coexistence of two stable phase-locked oscillations and several unstable mirror-reflecting waves and standing waves. (C) 1999 Elsevier Science Ltd. All rights reserved.

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

neuron phase-locking wave multistability


Supervised automatic evaluation for summarization with voted regression model The high quality evaluation of generated summaries is needed if we are to improve automatic summarization systems. Although human evaluation provides better results than automatic evaluation methods, its cost is huge and it is difficult to reproduce the results. Therefore, we need an automatic method that simulates human evaluation if we are to improve our summarization system efficiently. Although automatic evaluation methods have been proposed, they are unreliable when used for individual summaries. To solve this problem, we propose a supervised automatic evaluation method based on a new regression model called the voted regression model (VRM). VRM has two characteristics: (1) model selection based on corrected AIC to avoid multicollinearity, (2) voting by the selected models to alleviate the problem of overfitting. Evaluation results obtained for TSC3 and DUC2004 show that our method achieved error reductions of about 1751% compared with conventional automatic evaluation methods. Moreover, our method obtained the highest correlation coefficients in several different experiments.

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

automatic summarization
automatic evaluation
regression model

text summarization challenge
document understanding conference


Classification of laryngeal disorders based on shape and vascular defects of vocal folds Vocal folds on videolaryngostroboscopy images are detected by HOG for examination. Vocal fold images are classified into five laryngeal disorder types. We exploit shape and vascular features of vocal folds for classification. An average classification success rate of 81% is achived. We demonstrate that visible vessels of vocal folds can act as a prognostic marker.

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

laryngeal image analysis
classification of vocal fold disorders
histogram of oriented gradients
vascular vectors
vessel centerline extraction
measurement of vocal fold shape defects


Analysis of feature selection stability on high dimension and small sample data Feature selection is an important step when building a classifier on high dimensional data. As the number of observations is small, the feature selection tends to be unstable. It is common that two feature subsets, obtained from different datasets but dealing with the same classification problem, do not overlap significantly. Although it is a crucial problem, few works have been done on the selection stability. The behavior of feature selection is analyzed in various conditions, not exclusively but with a focus on t t -score based feature selection approaches and small sample data. The analysis is in three steps: the first one is theoretical using a simple mathematical model; the second one is empirical and based on artificial data; and the last one is based on real data. These three analyses lead to the same results and give a better understanding of the feature selection problem in high dimension data.

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

feature selection
small sample
stability

low n/d n / d ratio n/d n / d n/d n / d n / d


a comparison of messy ga and permutation based ga for job shop scheduling This paper presents the results of a fair comparison between a messy GA and a permutation based simple GA as applied to a job shop scheduling system. An examination is made at a macro level in terms of performance and quality of schedules achieved and conclusions are drawn as to the superiority of messy GA or otherwise.

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

repeating permutation representation
messy genetic algorithms


Exploring Motor Cortical Plasticity Using Transcranial Magnetic Stimulation in Humans Abstract: It is generally accepted that functional properties of the motor cortex in adult humans can be altered through behavioral or pharmacological manipulations, as well as in some pathological conditions. The ability and capacity of adult human cortex to undergo any adaptive or reorganizational changes is referred to as plasticity. Much of the evidence concerning motor cortical plasticity have been derived from studies using the non-invasive technique of transcranial magnetic stimulation (TMS). TMS has proven to be a suitable tool to explore representational plasticity and to interact with neuronal activity in settings of induction protocols either alone or coupled with altered sensory inputs. Furthermore, plastic changes induced by motor learning protocols have attracted particular interest because of their relevance in functional recovery. Recent studies support the view that learning in human motor cortex occurs through long-term potentiation (LTP)-like mechanisms. Purposeful modulation of motor cortical plastic changes by manipulative TMS protocols may offer useful rehabilitative strategies in patients with chronic motor deficits.

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 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 I O O O O O O O O O O O O O O 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 O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

transcranial magnetic stimulation
motor learning
human


Supporting conceptual awareness with pedagogical agents This paper describes a series of efforts in building and conceptualizing software agents for distributed collaborative learning. The agents are referred to as pedagogical agents. We have integrated pedagogical agents within two collaborative environments, TeamWave Workplace and Future Learning Environment. The role of agents in these environments differs from past work on software agents in their function as extended awareness mechanisms, focusing on task and concept awareness (conceptual awareness). Our approach is stimulated by Meads theory of the 'Generalized Other'. The agents collect statistical information on user activity and analyze the information based on principles of collaboration and knowledge building (participation, group interaction, and scientific discourse). Furthermore, the agents define a trajectory in a pedagogical agent design space, which we define in terms of four dimensions: presentation, intervention, task, and pedagogy. We end the paper by comparing our approach with related work.

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

group interaction
generalized other
awareness
pedagogical agents


A characteristic particle method for the Saint Venant equations A novel characteristic particle method is developed for the Saint Venant equations in the present study. Contrary to the conventional fixed-grid or moving particle methods, the present formulation is built by reallocating the computational particles along the characteristic curves. Both the right- and left-running characteristics are faithfully traced and imitated with their associated computational particles. The annoying numerical nuisance in realizing advection term for the fixed-grid arrangement can be effectively gotten rid of. Besides, special particles with dual states to the enforcement of the Rankine-Hugonlot relation are deliberately imposed to emulate the shock structure. Efficacy of this formulation is verified by solving some benchmark problems with significant transient effects. Computational results are meticulously compared with available analytical solutions. It is concluded that the proposed characteristic particle method will be a useful tool to replicate transient phenomena revealed by the Saint Venant equations. (C) 2013 Elsevier Ltd. All rights reserved.

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

characteristic particle method
saint venant equations

dual-state particle
rankine-hugoniot relation
open-channel flow
dam-break flow
tidal bore flow


Performance Analysis of a Device-to-Device Communication-Based Random Access Scheme for Machine-Type Communications Group paging was proposed by the 3rd generation partnership project to reduce the awesome paging overhead in machine-type communication (MTC) that usually involves a huge number of devices performing small data transmissions. Under group paging, MTC devices with identical or similar traffic characteristics are assembled into a paging group; and all the devices in a paging group is paged by a single group paging message. After receiving a group paging message, all the devices in a paging group simultaneously contend for the random access channel to transmit their random access requests, thereby resulting in congestion in the random access network in the case of large group size. To tackle this problem of group paging, we previously proposed an improved random access (I-RA) scheme. In this paper we develop a mathematical model based on Poisson arrival approximation method to analyze the performance of the I-RA scheme. We derive closed-form analytical formulas for performance metrics, such as successful access probability, collision probability, average access delay, the cumulative distribution function of preamble transmission, etc. The accuracy of the analytical formulas is validated through simulation. Based on the formulas, we conduct a numerical study to investigate the impact of diverse parameters on the performance of the I-RA scheme. Moreover, we compare the performance between the I-RA scheme and the existing schemes by numerical studies. The mathematical model developed and the formulas derived in this paper can guide the implementation of the I-RA scheme in MTC.

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

device-to-device communications
cluster communication
machine type communications


FastInf: An Efficient Approximate Inference Library The FastInf C++ library is designed to perform memory and time efficient approximate inference in large-scale discrete undirected graphical models. The focus of the library is propagation based approximate inference methods, ranging from the basic loopy belief propagation algorithm to propagation based on convex free energies. Various message scheduling schemes that improve on the standard synchronous or asynchronous approaches are included. Also implemented are a clique tree based exact inference, Gibbs sampling, and the mean field algorithm. In addition to inference, FastInf provides parameter estimation capabilities as well as representation and learning of shared parameters. It offers a rich interface that facilitates extension of the basic classes to other inference and learning methods.

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

graphical models
loopy belief propagation
approximate inference


Pumping test interpretation by combination of Latin hypercube parameter sampling and analytical models Pumping tests in groundwater reservoirs are a much used and recommended method to derive hydraulic properties of aquifers and aquitards at the field scale. Interpretation of pumping tests can be done by fitting analytical or numerical models to the obtained field data using optimisation procedures. In this paper, an interpretation methodology is presented and implemented in the form of a computer code that combines analytical solutions for confined, semi-confined and unconfined single and multiple layer schematisations, with random parameter generator routines to find best fitting parameter sets to measured pumping test data. As this requires a large number of Monte Carlo (MC) runs, the number of required simulations is restricted by using a stratified instead of a pure random sampling technique. Latin hypercube sampling (LHS) is used as the stratified random sampler. The analytical solutions are defined in the Laplace domain and inverted numerically using the well-known Stehfest algorithm. The program uses a number of iteration cycles during which parameters sets are generated within predefined limits using the LHS technique. Parameters sets which satisfy a chosen maximum value for a selected objective function (root mean square (RMSE) or mean relative deviation (MRD)) are retained and used to update parameter limits for the next cycle. The objective function criterion is decreased during subsequent cycles while the limits of the sampling intervals are adapted. The number of determinable parameters is dependent on the aquifer schematisation and conceptual model that is chosen. After each cycle, statistics of the parameter values of the realisations which satisfy the objective function criterion are calculated. The method is demonstrated with examples including synthetic datasets and field data. The synthetic data examples show that the program is able to retrieve the parameter values used for generating drawdown sets very well. Typical runtimes on a PC are no more than a few minutes. The program can easily be extended with additional analytical solutions for other schematisations.

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

groundwater
pumping test
interpretation
latin hypercube sampling

hydraulic parameters
analytical solution


Determining the sampling time frame for In-Vehicle Data Recorder measurement in assessing drivers Method for choosing the required sampling time frame for In-Vehicle Data Recorders. The method is demonstrated on cab driver population IVDR data. Analysis indicates that ?300h per driver result in a stable driving pattern. Future use of method in evaluation of driving patterns and changes over time.

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

in-vehicle data recorder
driving behavior patterns
driving assessments


Intermediate storage in batch processing systems under stochastic equipment failures The role of intermediate storage in buffering a process train from the effects of stochastically varied equipment failures is studied. Two models of upstream failures are investigated Analytical formulae are derived for the distributions of minimal and maximal values of the intermediate storage hold up, by means of which the favorable storage volume can be determined. Also, an algorithm and computer program is presented for designing the favorable volume of an intermediate storage. The program can also be used for studying the general behavior of such systems with the aid of simulation. An example is presented for illustrating the applicability of the analytical formulae and the computer program in sizing the intermediate storage in batch processing systems. (C) 1998 Published by Elsevier Science Ltd. All rights reserved.

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

batch operation
stochastic equipment failure
hold up variation


Dynamic customer lifetime value prediction using longitudinal data: An improved multiple kernel SVR approach Customer lifetime value (CLV), as an important metric in customer relationship management (CRM), has attracted widespread attention over the last decade. Most CLV prediction models do not take into consideration the dynamics of the customer purchase behavior and changes of the marketing environment such as the adoption of different promotion policies. In this study, a framework for the dynamic CLV prediction using longitudinal data is presented. In the framework, both the dynamic customer purchase behavior and customized promotions are considered. An improved multiple kernel support vector regression (MK-SVR) approach is developed to predict the future CLV and select the best promotion using both the customer behavioral variables and controlled variable about multiple promotions. Computational experiments using two databases show that the MK-SVR exhibits good prediction performance and the usage of longitudinal data in the MK-SVR facilitate the dynamic prediction and promotion optimization.

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

customer relationship management
customer lifetime value

data mining
dynamic multi-step-ahead prediction
support vector machine
multiple kernel learning


Real-time constrained linear discriminant analysis to target detection and classification in hyperspectral imagery In this paper, we present a constrained linear discriminant analysis (CLDA) approach to hyperspectral image detection and classification as well as its real-time implementation. The basic idea of CLDA is to design an optimal transformation matrix which can maximize the ratio of inter-class distance to intra-class distance while imposing the constraint that different class centers after transformation are along different directions such that different classes can be better separated. The solution turns out to be a constrained version of orthogonal subspace projection (OSP) implemented with a data whitening process. The CLDA approach can be applied to solve both detection and classification problems. In particular, by introducing color for display the classification is achieved with a single classified image where a pre-assigned color is used to display a specified class. The real-time implementation is also developed to meet the requirement of on-line image analysis when the immediate data assessment is critical. The experiments using HYDICE data demonstrate the strength of CLDA approach in discriminating the targets with subtle spectral difference.

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

detection
classification
hyperspectral imagery

constrained linear discriminant analysis (clda)


A novel acknowledgment-based approach against collude attacks in MANET Routing misbehavior and collusion attack in Mobile Ad Hoc Networks (MANETs) are the main topics in this paper. Various techniques prevent routing misbehaviors have been published, but most of them do not consider the collusion attacks. Therefore, we propose the scheme called NACK to simultaneously detect routing misbehavior and collusion attacks, and to mitigate the effects of routing attacks. Furthermore, NACK scheme adopts an acknowledgment-based approach and timestamps comparison to resist the attacks mentioned above. The security analysis and simulation results are presented to evaluate the performance of NACK.

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


Flexible case-based retrieval for comparative genomics Comparative genomics represents a key instrument to discover or validate phylogenetic relationships, to give insights on genome evolution, and to infer metabolic functions of a given organism. A tool for properly supporting comparative genomics is of paramount importance in several application domains.

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

case-based reasoning
flexible retrieval
index-based retrieval
interactivity


The role of early fundamental frequency rises and elbows in French word segmentation The study examined intonational cues to word beginnings in French. French has an optional early rise in fundamental frequency (F0) starting at the beginning of a content word. The role of this rise in segmentation by human listeners had previously been suggested, but not empirically tested. In Experiment 1, participants listened to noise-masked items like le ballon de mmentos/le ballon de mes manteaux , differing in segmentation and presence of an early rise. They interpreted early rises as markers of content word beginnings. In Experiment 2, the alignment of the early rise was manipulated in nonword sequences like [me.la.m ? .din]. Listeners were more likely to perceive two words (mes lamondines) when the early rise started at the second syllable and a single content (non)word (mlamondine) when it started at the first. Experiment 3 showed that a simple F0 elbow at a function wordcontent word boundary also cued a content word beginning. This pattern and its potential use in word segmentation had not been previously reported in the literature. These intonational cues, like other cues to word segmentation, influenced rather than determined segmentation decisions. The influence of other cues (e.g., duration, word frequency) is also discussed. These results are the first evidence that French listeners use intonational information as cues to content word beginning. These cues are particularly important because the beginning of a word is a privileged position in word recognition and because, unlike many other cues (e.g., stress in English), they identify actual rather than potential word boundaries. The results provide support for an autosegmental-metrical account of the intonational phonology of French in which the early rise is a bitonal (LH) phrase accent that serves as a cue to content word beginnings. The cue is strongest when both tones (LH) are realized, which leads to an early rise, but can still be used if only the L is realized, which leads to a simple elbow. These results illustrate the importance of expanding studies of the range of cues to word segmentation to include intonational cues.

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


Language and Emotional Knowledge: A Case Study on Ability and Disability in Williams Syndrome Williams Syndrome provides a striking test case for discourses on disability, because the characteristics associated with Williams Syndrome involve a combination of abilities and disabilities. For example, Williams Syndrome is associated with disabilities in mathematics and spatial cognition. However, Williams Syndrome individuals also tend to have a unique strength in their expressive language skills, and are socially outgoing and unselfconscious when meeting new people. Children with Williams are said to be typically unafraid of strangers and show a greater interest in contact with adults than with their peers. This apparently keen social knowledge is a counterexample to the discussion of disability among academic philosophers, especially philosophers in the early modern period. Locke infamously used the example of disability to claim that Descartes arguments in favor of innate ideas were incorrect. On the contrary, Williams Syndrome may stand as an example of innate social knowledge; something that could benefit current discourse in philosophy, disability theory, and medical ethics.

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

self-reflexive attitudes
sociability
hyperlexia
amygdala
planum temporale


A refactoring method for cache-efficient swarm intelligence algorithms With advances in hardware technology, conventional approaches to software development are not effective for developing efficient algorithms for run-time environments. The problem comes from the overly simplified hardware abstraction model in the software development procedure. The mismatch between the hypothetical hardware model and real hardware design should be compensated for in designing an efficient algorithm. In this paper, we focus on two schemes: one is the memory hierarchy, and the other is the algorithm design. Both the cache properties and the cache-aware development are investigated. We then propose a few simple guidelines for revising a developed algorithm in order to increase the utilization of the cache. To verify the effectiveness of the guidelines proposed, optimization techniques, including particle swarm optimization (PSO) and the genetic algorithm (GA), are employed. Simulation results demonstrate that the guidelines are potentially helpful for revising various algorithms.

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

cache
memory hierarchy
swarm intelligence
particle swarm optimization
genetic algorithm


Optimizing goods assignment and the vehicle routing problem with time-dependent travel speeds Many mathematical models have been presented for the vehicle routing problem (VRP) in research papers. Most of them assume that the travel speeds are constant, and ignore the fact that travel speeds can change throughout the day. In this research, based on time-dependent travel speeds, an optimization method is proposed for solving goods assignment and vehicle routing problems. Moreover, in the optimization method, the travel time calculation satisfies the "non-passing" property, which is ignored in most research papers. A real case of a 3C warehousing company and a larger simulated problem are introduced to illustrate the proposed method. The results show that the proposed method is efficient and effective in solving problems. Crown Copyright (C) 2009 Published by Elsevier Ltd. All rights reserved.

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


Low-Complexity Constant Multiplication Based on Trigonometric Identities with Applications to FFTs In this work we consider optimized twiddle factor multipliers based on shift-and-add-multiplication. We propose a low-complexity structure for twiddle factors with a resolution of 32 points. Furthermore, we propose a slightly modified version of a previously reported multiplier for a resolution of 16 points with lower round-off noise. For completeness we also include results on optimal coefficients for eight-points resolution. We perform finite word length analysis for both coefficients and round-off errors and derive optimized coefficients with minimum complexity for varying requirements.

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

complex multiplier
fft
shift-and-add multiplication


Improved Model- and View-Dependent Pruning of Large Botanical Scenes We present an optimized pruning algorithm that allows for considerable geometry reduction in large botanical scenes while maintaining high and coherent rendering quality. We improve upon previous techniques by applying model-specific geometry reduction functions and optimized scaling functions. For this we introduce the use of Precision and Recall (PR) as a measure of quality to rendering and show how PR-scores can be used to predict better scaling values. We conducted a user-study letting subjects adjust the scaling value, which shows that the predicted scaling matches the preferred ones. Finally, we extend the originally purely stochastic geometry prioritization for pruning to account for view-optimized geometry selection, which allows to take global scene information, such as occlusion, into consideration. We demonstrate our method for the rendering of scenes with thousands of complex tree models in real-time.

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

precision/recall
level of detail
tree rendering


Losses scaling in soft magnetic materials Purpose - The paper presents an application of the scaling theory in a description of energy losses in soft magnetic materials in order to improve an agreement between measurements and theoretical models. Design/methodology/approach - The scaling theory allows the description of energy losses by a generalized homogenous function, which depends on scaling exponents alpha, beta and amplitudes Gamma((n)). The values of the scaling exponents and amplitudes were estimated on the basis of measurement data of total energy losses. Findings - The main findings of the paper are: the linear relationships between the scaling exponents a and 13, the data collapse of energy losses and the scaling laws for asymptotic exponents of energy losses derivatives. Research limitations/implications - The origin of the data collapse and the relationship between the scaling exponents will be the subject of further research with the aid of renormalization group method. Practical implications - The paper could be useful both for device designers and researchers involve in computational electromagnetism. Particularly, the data collapse allows a comparison of energy loss values measured in laboratories on different samples and by different methods. Originality/value - The application of the scaling theory in a description of energy losses in soft magnetic materials improves an agreement between measurement and theoretical models.

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

physical properties of materials
magnetism


Open-source tools for dynamical analysis of Liley's mean-field cortex model A parallel open-source implementation of Liley's mean-field cortex model, in PETSc. We implement fully implicit time integration of nonlinear and variational equations. We perform equilibrium continuation, with computation of inhomogeneous eigenmodes. We compute periodic solutions with NewtonKrylov iteration.

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

hyperbolic partial differential equations

numerical partial differential equations


Static worst-case lifetime estimation of wireless sensor networks: A case study on VigilNet This paper proposes a feasible static analysis approach to estimate the worst-case lifetime of WSNs, with specific focus on VigilNet. We statically estimate the lifetime of each node in VigilNet with a fixed initial energy budget through a hybrid approach, which integrates an Integer Linear Programming (ILP) based method to obtain the worst-case CPU energy consumption and domain-specific scenarios analysis to compute the worst-case radio energy consumption. Our experimental results indicate that this static approach can safely and accurately estimate the worst-case lifetime for WSNs.

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

worst-case lifetime
static timing analysis
worst-case energy consumption


Corner occupying theorem for the two-dimensional integral rectangle packing problem This paper proves a corner occupying theorem for the two-dimensional integral rectangle packing problem, stating that if it is possible to orthogonally place n arbitrarily given integral rectangles into an integral rectangular container without overlapping, then we can achieve a feasible packing by successively placing a rectangle onto a bottom-left corner in the container. Based on this theorem, we might develop efficient heuristic algorithms for solving the integral rectangle packing problem. In fact, as a vague conjecture, this theorem has been implicitly mentioned with different appearances by many people for a long time.

B I I O O O O B I 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 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

rectangle packing
corner occupying theorem


18 Mbit/s carrier frequency offset-spread spectrum (CFO-SS) system using 2.4 GHz ISM band A wireless communications system with a transmission speed of 18 Mbit/s is presented using the 2.4 GHz ISM band. This system employs the "Carrier Frequency Offset-Spread Spectrum (CFO-SS)" scheme and the "Dual-Polarization Staggered Transmission (DPST)" scheme. The 18 Mbit/s CFO-SS system (named "CFO-SS18") was developed and its performance evaluated in fields. In this paper, the detailed operating principle of CFO-SS and DPST schemes, together with the specifications and structures of CFO-SS 18, are presented. Results of indoor and field tests obtained by using CFO-SS18 are also presented.

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

cfo-ss
wireless access
high speed
2.4 ghz ism band
dual-polarization technique


three dimensional threaded fastener meshing algorithm Understanding the stresses in the root of a thread of a bolt has never been easy. Ideally one would like to put a strain gage right at the root and measure them directly, but the placement of the gage and its wires are impossible without changing the insitu environment. Engineers then turned to analytical models, but soon discovered that two dimensional models where not giving the correct results because the geometry is not axis symmetric and three dimensional models where too difficult to mesh with today's CAD tools. A team consisting of Ford engineers and computer programers developed a program that will automatically generate a full three dimensional model of a thread fastener and mating threaded block by using a combination of cylindrical meshing techniques and a method of revolving profiles in a helical coordinate system. The bolt meshing program is able to input parameters about the thread fastener and block: diameter, pitch, length, etc., and output a complete three dimensional model in the form of an ABAQUS or NASTRAN finite element input deck. This model can then run through the ABAQUS finite element program and the resulting stress field computed. This paper will focus on the algorithm used to generate the mesh.

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


Measurements of flow distribution in a thin resin layer during ultraviolet nanoimprint lithography by means of digital holographic particle-tracking velocimetry Micro-DHPTV was used to measure an UV-curable resin flow at in situ NIL process. We succeeded in measuring the 4-dimensions flow distribution in the thin resin layer. It was clearly shown that the presence of a release agent affects the UV-curable resin flow. We believe this study will provide a better understanding of the flow behavior of UV-curable resins.

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

particle-tracking velocimetry
flow measurement
uv-curable resin


An approach to multi-modal human-machine interaction for intelligent service robots The paper describes a multi-modal scheme for human-robot interaction suited for a wide range of intelligent service robot applications. Operating in un-engineered, cluttered, and crowded environments, such robots have to be able to actively contact potential users in their surroundings and to offer their services in an appropriate manner. Starting from a real application scenario, the usage of a robot as mobile information kiosk in a home store, some reliable methods for vision-based interaction, sound analysis and speech output have been developed. These methods are integrated into a prototypical interaction cycle that can be assumed as a general approach to human-machine interaction. Experimental results demonstrate the strengths and weaknesses of the proposed methods. (C) 2003 Elsevier Science B.V. All rights reserved.

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

human-robot interaction
people detection
people tracking
service robot application
multi-modal interaction


Effects of a fractional friction with power-law memory kernel on string vibrations In this paper we give an analytical treatment of a wave equation for a vibrating string in the presence of a fractional friction with power-law memory kernel. The exact solution is obtained in terms of the Mittag-Leffler type functions and a generalized integral operator containing a four parameter Mittag-Leffler function in the kernel. The method of separation of the variables, Laplace transform method and SturmLiouville problem are used to solve the equation analytically. The asymptotic behaviors of the solution of a special case fractional differential equation are obtained directly from the analytical solution of the equation and by using the Tauberian theorems. The proposed model may be used for describing processes where the memory effects of complex media could not be neglected.

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

frictional power-law memory kernel
caputo time fractional derivative
mittag-leffler function
fractional integral operator
fractional differential operator


A version of the Swendsen-Wang algorithm for restoration of images degraded by Poisson noise An algorithm for restoration of images degraded by Poisson noise is proposed. The algorithm belongs to the family of Markov chain Monte Carlo methods with auxiliary variables. We explicitly use the fact that medical images consist of finitely many, often relatively few, grey-levels. The continuous scale of grey-levels is discretized in an adaptive way, so that a straightforward application of the Swendsen-Wang (Phys. Rev. Lett. 58 (1987) 86) algorithm becomes possible. Partial decoupling method due to Higdon (J. Am. Statist. Assoc. 93 (1998) 442, 585) is also incorporated into the algorithm. Simulation results suggest that the algorithm is reliable and efficient. (C) 2002 Pattern Recognition Society. Published by Elsevier Science Ltd. All rights reserved.

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

bayesian image restoration
gibbs distributions
gibbs sampler
swendsen-wang algorithm
intensity estimation


Sampling of discrete materials - II. Quantitative approach-sampling of zero-dimensional objects Parts II and III of this series are initiated by a joint discussion of features related to the lot. Part II then delineates the central elements of the Theory of Sampling for zero-dimensional objects. It is necessary to be brief within the limited format of the present tutorial series, but all essential model rigour has been maintained. An attempt has been made to focus on the central mathematical theoretical core of TOS while also showing how this relates directly to sampling practise (materials, equipment and procedures). A highlight of the latter issue concerns experimental estimation of the Fundamental Sampling Error (FSE). Part II is also fundamental for further developments in Part III, as it presents a complete overview discussion of the basic sampling operation of the one-dimensional object as well. (C) 2004 Elsevier B.V. All rights reserved.

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

quantitative approach
zero-dimensional objects
sampling of particulate matter


Comparison of aligned Friedman rank and parametric methods for testing interactions in split-plot designs Parametric methods are commonly used despite evidence that model assumptions are often violated. Various statistical procedures have been suggested for analyzing data from multiple-group repeated measures (i.e., split-plot) designs when parametric model assumptions are violated (e.g., Akritas and Arnold (J. Amer. Statist. Assoc. 89 (1994) 336); Brunner and Langer (Biometrical J. 42 (2000) 663)), including the use of Friedman ranks. The effects of Friedman ranking on data and the resultant test statistics for single sample repeated measures designs have been examined (e.g., Harwell and Serlin (Comput. Statist. Data Anal. 17 (1994) 35; Comm. Statist. Simulation Comput. 26 (1997) 605); Zimmerman and Zumbo (J. Experiment. Educ. 62 (1993) 75)). However, there have been fewer investigations concerning Friedman ranks applied to multiple groups of repeated measures data (e.g., Beasley (J. Educ. Behav. Statist. 25 (2000) 20); Rasmussen (British J. Math. Statist. Psych. 42 (1989) 91)). We investigate the use of Friedman ranks for testing the interaction in a split-plot design as a robust alternative to parametric procedures. We demonstrated that the presence of a repeated measures main effect may reduce the power of interaction tests performed on Friedman ranks. Aligning the data before applying Friedman ranks was shown to produce more statistical power than simply analyzing Friedman ranks. Results from a simulation study showed that aligning the data (i.e., removing main effects) before applying Friedman ranks and then performing either a univariate or multivariate test can provide more statistical power than parametric tests if the error distributions are skewed.

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

friedman ranks
repeated measures
interaction tests


Exposing HPC and sequential applications as services through the development and deployment of a SaaS cloud A framework for the deployment of SaaS clouds aimed at supporting scientific research. A novel resource selection approach which can automate complex deployment methodologies such as cloud bursting. Simplified deployment of Software as a Services through the publication of attributes. The automated development of hybrid HPC clouds. Framework and cloud feasibility and performance proofs demonstrated through a bio-informatics workflow.

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

hpc application service
application deployment and exposure
high performance computing


A combinatorial problem on Trapezoidal words In this paper, we investigate some combinatorial properties concerning the family of the so-called Trapezoidal words. Trapezoidal words, considered in de Luca (Theoret. Comput. Sci. 218 (1999) 13-39) are finite words over the two-letter alphabet A = {a, b} whose subword complexity has the same behaviour as that of finite Sturmian words. In de Luca (Theoret. Comput. Sci. 218 (1999) 13-39) it has been proved that the family of Finite Sturmian words is properly contained in that one of Trapezoidal words. We carry on with the studying of the family of Trapezoidal words and, in particular, of its relation with that one of finite Sturmian words. (C) 2002 Published by Elsevier Science B.V.

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


Pattern-oriented associative rule-based patent classification This paper proposes an innovative pattern-oriented associative rule-based approach to construct automatic TRIZ-based patent classification system. Derived from associative rule-based text categorization, the new approach does not only discover the semantic relationship among features in a document by their co-occurrence, but also captures the syntactic information by manually generalized patterns. We choose 7 classes which address 20 of the 40 TRIZ Principles and perform experiments upon the binary set for each class. Compared with three currently popular classification algorithms (SVM, C4.5 and NB), the new approach shows some improvement. More importantly, this new approach has its own advantages, which were discussed in this paper as well.

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

triz
patent classification
text categorization

triz principles
associated rule-based approach


An evolutionary algorithm for pure fuzzy flowshop scheduling problems The pure flowshop scheduling problem is here investigated from a perspective considering me uncertainty associated with the execution of shop floor activities. Being the flowshop problem is NP complete, a large number of heuristic algorithms have been proposed in literature to determine an optimal solution. Unfortunately, these algorithms usually assume a simplifying hypothesis: the problem data are assumed as deterministic, i.e. job processing times and the due dates are expressed through a unique value, which does not reflect the real process variability. For this reason, some authors have recently proposed the use of a fuzzy set theory to model the uncertainty in scheduling problems. In this paper, a proper genetic algorithm has been developed for solving the fuzzy flowshop scheduling problem. The optimisation involves two different objectives: the completion time minimisation and the due date fulfilment; both the single and multi-objective configurations have been considered. A new ranking criterion has been proposed and its performance has been tested through a set of test problems. A numerical analysis confirms the efficiency of the proposed optimisation procedure.

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

fuzzy scheduling
optimisation algorithms


From cluster ensemble to structure ensemble This paper investigates the problem of integrating multiple structures which are extracted from different sets of data points into a single unified structure. We first propose a new generalized concept called structure ensemble for the fusion of multiple structures. Unlike traditional cluster ensemble approaches the main objective of which is to align individual labels obtained from different clustering solutions, the structure ensemble approach focuses on how to unify the structures obtained from different data sources. Based on this framework, a new structure ensemble approach called the probabilistic bagging based structure ensemble approach (BSEA) is designed, which integrates the bagging technique, the force based self-organizing map (FBSOM) and the normalized cut algorithm into the proposed framework. BSEA views structures obtained from different datasets generated by the bagging technique as nodes in a graph, and adopts graph theory to find the most representative structure. In addition, the force based self-organizing map (FBSOM), which is a generalized form of SOM, is proposed to serve as the basic clustering algorithm in the structure ensemble framework. Finally, a new external index called correlation index (CI), which considers the correlation relationship of both the similarity and dissimilarity between the predicted solution and the true solution, is proposed to evaluate the performance of BSEA. The experiments show that (i) The performance of BSEA outperforms most of the state-of-the-art clustering approaches, and (ii) BSEA performs well on datasets from the UCI repository and real cancer gene expression profiles.

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


On the Finite Increment Calculus method for stabilizing advection-diffusion equations, analysis and computation of the stabilization parameter In this work we are concerned with the finite increment calculus (FIC) method. The method has been developed for efficient approximation of advection-diffusion equations with high Peclet numbers. Since the natural application of FIC is within the framework of the FEM, we consider the BVP in a weak sense on finite dimensional spaces. Here we provide a result on existence and uniqueness of the solution as well as an error analysis. Also we propose a choice of the stabilization parameter. We test the method on some troublesome 2D problems. Copyright (C) 2011 John Wiley & Sons, Ltd.

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

finite increment calculus
stabilization parameter

advection-diffusion
peclet number
sharp gradient
stabilized-fem


Term structure of interest rates and the expectation hypothesis: The euro area This paper investigates the informational content of the yield curve in the European market using data on the Italian term structures. According to the expectation hypothesis theory (EHT) the current forward rate equals the future short rate plus a constant risk premium that is time invariant but maturity dependent. This theory has been widely tested in the empirical literature providing various findings according to the country where it has been applied and to the segment of the yield curve examined or the period under study. The standard approach to test the EHT uses the regression techniques assuming data on spot rates and their first differences to be stationary. Recently an increasing number of studies evidenced the non stationarity of interest rates time series and some tests of the EHT are formulated using term spread and forward-spot spread which are stationary. A new strand of literature suggests to investigate the EHT using a restricted VAR framework. In this paper, following [Jondeau, E., Ricart, R., 1999. The expectations hypothesis of the term structure: tests on us, german, french and uk euro-rates. Journal of International Money and Finance 18, 725750, Ghazali, N.A. Low, S.W., 2002. The expectations hypothesis in emerging financial markets: the case of malaysia. Applied Economics 34, 11471156 and Seo, B., 2003. Non linear mean reversion in the term structure of interest rates. Journal of Economic Dynamics and Control 27, 22432265], we test if the expectation hypothesis holds using cointegration and error correction analysis. For the period under study results suggest that the long and short term interest rates are cointegrated and therefore subject to a long equilibrium path, providing evidence that the EHT holds for the Italian and the European market.

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

term structure of interest rates
expectations hypothesis
cointegration


Towards content-based patent image retrieval: A framework perspective In this article, we discuss the potential benefits, the requirements and the challenges involved in patent image retrieval and subsequently, we propose a framework that encompasses advanced image analysis and indexing techniques to address the need for content-based patent image search and retrieval. The proposed framework involves the application of document image pre-processing, image feature and textual metadata extraction in order to support effectively content-based image retrieval in the patent domain. To evaluate the capabilities of our proposal, we implemented a patent image search engine. Results based on a series of interaction modes, comparison with existing systems and a quantitative evaluation of our engine provide evidence that image processing and indexing technologies are currently sufficiently mature to be integrated in real-world patent retrieval applications.

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

content-based search
images
drawings
figures
hybrid


Development and application of a framework for evaluating multi-mode voting risks Purpose - The purpose of this paper is to investigate the risks associated with online voting and to compare them with more traditional voting modes. Design/methodology/approach - A modified version of the Operationally Critical Threat, Asset, and Vulnerability Evaluation (OCTAVE) approach from the CERT Coordination Center (R) at Carnegie-Mellon University is used for developing a framework for comparing threats for different stakeholders. In addition, these risks and threats are quantified, offering an opportunity to conduct a multi-mode risk analysis in a manner independent of the underlying voting modes. The framework is exemplified using data from officials who had been involved in an actual municipal election, in which registered voters were given the option of voting through the Internet. Findings - What is instructive in the context of this study is that the "low-tech" threats such as large-scale mail theft of election notifications and family member coercion may in fact be significant for Internet voting, and the sensationalized threats mentioned by the media may pale in comparison in terms of vulnerabilities. Research limitations/implications - Conclusions drawn from applying the methods may be very sensitive to parameters chosen for quantification, especially since estimates of probabilities of threats may vary in order of magnitude. Originality/value - This paper demonstrates a quantitative and comparative analysis for Internet voting, something which does not seem to be adequately addressed in the literature.

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


E-learning multimedia applications: Towards an engineering of content creation In the same manner that e-learning applications are becoming increasingly important at the university, there are still some critical questions that should be solved with the objective of making use of the potential offered by current Web Technologies. The creation of contents that are able of capturing the attention of interest of the students and their disposal in an appropriate way constitute the main purpose of this work. The teaching content engineering expounded shows the different stages that should form part of the process. A development team, composed of different professional profiles, will work together with the lecturers of the subject to which the contents are been created, i.e. multimedia videos and interactive applications. This process should be developed according to a methodology that assure the use of appropriate resources, all that tasks -suitable of being- should be modularized and factorized. This paper presents the acquired experience in the development and use of multimedia contents for e-learning applications, created for some of the subjects of the degree in computer science engineering. The deliveries of these contents make use of Internet and video streaming techniques. The result of the work shows the students satisfaction, including their comments.

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

didactic objectives
active learning
passive learning


Interpretation of partial least-squares regression models with VARIMAX rotation The VARIMAX rotation for factor analysis is used to orthogonally transform the factor subspace, resulting from partial least-square regression (PLSR). If the factors are nearly orthogonal, the transformation may help to interpret the physical meaning of each factor without altering the results of a PLSR model. A case study shows that after the VARIMAX rotation, the loading matrix satisfies the simple structure criterion and improves its explanatory ability.

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

factor subspace
varimax rotation
factor analysis


monitoring schedules for randomly deployed sensor networks Given n sensors and m targets, a monitoring schedule is a partition of the sensor set such that each part of the partition can monitor all targets. Monitoring schedules are used to maximize the time all targets are monitored when there is no possibility of replacing the batteries of the sensors. Each part of the partition is used for one unit of time, and thus the goal is to maximize the number of parts in the partition. We present distributed algorithms for Monitoring Schedule under the following assumptions: 1) identical sensors can each monitor all targets within a certain radius, 2) the n sensors are randomly distributed uniformly in a large square containing the targets, 3) the number of sensors is high enough given the area the square, and 4) the communication range is twice the sensing range (thus any two sensors which can monitor the same target can communicate in one hop). Our results hold with high probability. With the further assumptions that the sensors are capable (for example, by GPS) of knowing their exact geographic position, and targets fill out the square, our schedule has at least (1-?) opt parts, where opt is the optimum solution. Without geographic position we show that a previously proposed distributed algorithm can be modified to achieve a constant approximation ratio. Our algorithms run in a polylogarithmic number of communication rounds, with the exact running time depending on assumptions on the information a sensor receives when packets collide.

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

localized algorithm
approximation algorithm
sensor network


Axial and off-axial dynamic transitions in uniaxially anisotropic heisenberg ferromagnet: a comparison Uniaxially anisotropic Heisenberg ferromagnet, in the presence of a magnetic field varying sinusoidally in time, is studied by Monte Carlo simulation. The axial (field applied only along the direction of anisotropy) and off-axial (field applied only along the direction which is perpendicular to the direction of anisotropy) dynamic transitions are studied. By studying the distribution of the dynamic order parameter component, it is observed that the axial transition is discontinuous for low anisotropy and becomes continuous in high anisotropy. The off axial transition is found to be continuous for all values of anisotropy. In the infinite anisotropy limit, both types of transitions are compared with that observed in an Ising ferromagnet for the same value of the field and frequency. The infinitely anisotropic axial transition and dynamic transition in the Ising ferromagnet occur at different temperatures, whereas the infinitely anisotropic off-axial transition and the equilibrium ferro-para transition in the Ising model occur at the same temperature.

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 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

monte carlo simulation
heisenberg ferromagnet

dynamical phase transition
uniaxial anisotropy


performance of a riskfree time warp operating system Optimistic methods of synchronizing parallel discrete event simulations can be risky by sending (positive) messages (events) before they have been committed. Risky methods often use anti-messages (negative messages) to cancel incorrectly sent positive messages. Riskfree methods are more conservative, they do not send messages until they are known to be correct. The Time Warp Operating System (TWOS) uses anti-messages. Riskfree TWOS is implemented and tested on the standard TWOS benchmarks. Performance of the riskfree TWOS is dependent on the amount of lookahead in the simulation. Good lookahead was required for even reasonable performance. Tracker, a simulation of the riskfree simulation, is used to give idealized best case riskfree performance. BeRisky is an example simulation which has a speedup of n for Time Warp, but only a speedup of 2 for riskfree methods.

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

warp
speedup
use
simulation
event
parallel
performance
operating system
case

dependencies method examples benchmark message standardization timing posit


A real-time performance evaluation model for distributed software with reliability constrains In this paper, we propose an approach for the real-time performance analysis of distributed software with reliability constraints, called Athena. The approach is based on the real-time and reliability performance analysis of distributed program. In Athena, two important factors, imperfect nodes and the links reliability, are introduced. The algorithms proposed in Athena generates sub-graphs, counts the reliability of each sub-graph, calculates the transmission time for all the transmission paths of each data file, and computes response time of each data file with reliability constraint. In this way, the real-time performance of distributed software with reliability constrains can be evaluated.

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distributed software
reliability
performance evaluation


Improving the scalability of parallel N-body applications with an event-driven constraint-based execution model The scalability and efficiency of graph applications are significantly constrained by conventional systems and their supporting programming models. Technology trends such as multicore, manycore, and heterogeneous system architectures are introducing further challenges and possibilities for emerging application domains such as graph applications. This paper explores the parallel execution of graphs that are generated using the Barnes-Hut algorithm to exemplify dynamic workloads. The workloads are expressed using the semantics of an exascale computing execution model called ParalleX. For comparison, results using conventional execution model semantics are also presented. We find improved load balancing during runtime and automatic parallelism discovery by using the advanced semantics for exascale computing.

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A lossy 3D wavelet transform for high-quality compression of medical video In this paper, we present a lossy compression scheme based on the application of the 3D fast wavelet transform to code medical video. This type of video has special features, such as its representation in gray scale, its very few interframe variations, and the quality requirements of the reconstructed images. These characteristics as well as the social impact of the desired applications demand a design and implementation of coding schemes especially oriented to exploit them. We analyze different parameters of the codification process, such as the utilization of different wavelets functions, the number of steps the wavelet function is applied to, the way the thresholds are chosen, and the selected methods in the quantization and entropy encoder. In order to enhance our original encoder, we propose several improvements in the entropy encoder: 3D-conscious run-length, hexadecimal coding and the application of arithmetic coding instead of Huffman. Our coder achieves a good trade-off between compression ratio and quality of the reconstructed video. We have also compared our scheme with MPEG-2 and EZW, obtaining better compression ratios up to 119% and 46%, respectively for the same PSNR.

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

telemedicine
high-quality lossy compression


Partitioning of unstructured grid meshes using Boltzmann machine neural networks Properly adapted Boltzmann machine neural networks are used to devise effective unstructured grid partitioners that are capable of providing equally loaded grid subsets with minimum interface, for concurrent data-handling on parallel computers. The partitioning scheme is based on recursive bisections so that the outcome always consists of 2n partitions. Two different techniques are introduced to speed up theotherwise costlypartitioning process and several variants are considered. In particular, a transformation of bipolar Hopfield-type neural networks is developed providing an effective multi-scale approach. Results on a number of test cases are presented in order to assess the performance of the proposed techniques.

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


A note on the Hadwiger number of circular arc graphs The intention of this note is to motivate the researchers to study Hadwiger's conjecture for circular arc graphs. Let eta(G) denote the largest clique minor of a graph G, and let (X)(G) denote its chromatic number. Hadwiger's conjecture states that eta(G) >= (X)(G) and is one of the most important and difficult open problems in graph theory. From the point of view of researchers who are sceptical of the validity of the conjecture, it is interesting to study the conjecture for graph classes where eta(G) is guaranteed not to grow too fast with respect to (X)(G), since such classes of graphs are indeed a reasonable place to look for possible counterexamples. We show that in any circular arc graph G, eta(G) <= 2(X)(G) - 1, and there is a family with equality. So, it makes sense to study Hadwiger's conjecture for this family. (c) 2007 Elsevier B.V. All rights reserved.

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hadwiger's conjecture
graph coloring
combinatorial problems


A metadata driven approach to performing complex heterogeneous database schema migrations Enterprise software is evolving at a faster rate than ever before with customers expecting upgrades to occur regularly. These upgrades not only have complex consequences for legacy software but the database upgrade also. This paper discusses the challenges associated with relational database schema migrations which commonly occur with major upgrade releases of enterprise software. The most prevalent method of performing a schema migration is to execute SQL script files before or after the software upgrade. This approach performs poorly with large or complex database migrations and also requires separate script files for each supported database vendor. A tool was developed for a complex database upgrade of an enterprise product which uses XML in a metadata-driven approach. The key advantages include the ability to abstract complexity, provide multi-database vendor support and make the database migration more manageable between software releases. This marks an evolutionary step towards autonomic self-migrations.

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

autonomic database upgrades migrations metadata