A novel local extrema based gravitational search algorithm and its application in face recognition using one training image per class In this present paper a new methodology has been presented involving a stochastic optimization based approach to solve the face recognition problem with only one training image per class. Singular value decomposition (SVD) is used to decompose the single training image into two component images in order to compute the within class scatter matrix. The stochastic optimization approach is implemented employing gravitational search algorithm (GSA) which searches for an optimal transform matrix instead of using the traditional solution of general eigenvalue problem as is carried out in Fisher linear discriminant analysis (FLDA). The present paper also proposes two novel variants of GSA, namely the 2-D version of GSA, in order to cater for the 2-D image data, and the other one is a 2-D randomized local extrema based GSA (RLEGSA), which employs a stochastic local neighborhood based search instead of global search, as in basic GSA. Finally, a novel concept of performing an automated selection of projection vectors is incorporated in the 2-D RLEGSA to propose an improved variant, called the Modified RLEGSA (MRLEGSA). Experimental results, based on benchmark Yale A and ORL databases, show that the proposed methods outperform several existing schemes.

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

fisher linear discriminant analysis (flda)

2-d random local extrema gravitational search algorithm (2-d rlegsa)


Recommended Biometric Stress Management System The experiences of undergoing economic crises attest that the loss of employment prompts an outbreak of mental illnesses and suicides, increases the numbers of heart attacks and strokes and negatively affects other illnesses suffered by individuals under stress. Negative stress can devastate a person, cause depression, lower productivity on the job and the competitiveness of businesses and damage the quality of life. The Recommended Biometric Stress Management System, which the aforementioned authors of this article have developed, can assist in determining the level of negative stress and resolve the problem for lessening it. The system can help to manage current stressful situation and to minimise future stress by making the level of future need satisfaction more rational. In the first case, the system facilitates individuals to make a real-time assessment of their stress level and, after they fill in a stress management questionnaire, to get rational tips for the reduction of current stress based on the best global practice accumulated in the system. The multi-variant design and multiple criteria analysis methods are used for that purpose. The generation of recommendations and the selection of the most rational are based on criteria systems and on Maslows Hierarchy of Needs. Since this is an interdisciplinary area of research, psychologists, philosophers and experts in information management and decision-making theories and intelligent and biometric technologies participated in the development of this system. Over the course of this systems development, the biometric technologies of information, intelligence and voice were integrated. The case study submitted in this article demonstrates this developed system.

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

negative stress
maslows hierarchy of needs
recommendations

voice stress analysis
stress recognition
decision support system
historical information


INTEGRATING TECHNOLOGY ADDICTION AND USE: AN EMPIRICAL INVESTIGATION OF ONLINE AUCTION USERS Technology addiction is a relatively new mental condition that has not yet been well integrated into mainstream MIS models. This study bridges this gap and incorporates technology addiction into technology use processes in the context of online auctions. It examines how user cognition and ultimately usage intentions toward an information technology are distorted by addiction to the technology. The findings from two empirical studies of 132 and 223 eBay users, using three different operationalizations of addiction, indicate that the level of online auction addiction distorts the way the IT artifact is perceived. Informing a range of cognition-modification processes, addiction to online auctions augments user perceptions of enjoyment, usefulness, and ease of use attributed to the technology, which in turn influence usage intentions. Overall, consistent with behavioral addiction models, the findings indicate that users' levels of online auction addiction influence their reasoned IT usage decisions by altering users' belief systems. The formation of maladaptive perceptions is driven by a combination of memory-, learning-, and bias-based cognition modification processes. Implications of the,findings are discussed.

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

technology addiction
addiction
online auction
enjoyment

it continuance
user behavior
obsessive-compulsive behavior
intrinsic and extrinsic motivation


HER-2/neu Ile655Val Polymorphism and the Risk of Breast Cancer Genetic alterations of the proto-oncogene human epidermal growth factor receptor (HER-2/neu) have been shown to induce malignant transformation and metastasis. Genotyping studies have addressed the association of codon 655 isoleucine to valine polymorphism located in the transmembrane coding region and the risk of breast cancer, but the results are inconsistent. In this study, we investigated the association of HER-2/neu Ile655Val polymorphism and the risk of breast cancer in a Sudanese population. In addition, the joint effects of HER-2/neu variants and our previously reported ESR1C325G polymorphism were tested for their association with breast cancer risk. Candidate single nucleotide polymorphism (SNP) in HER-2/neu Ile655Val [db SNP rs1136200] was genotyped in breast cancer patients and in healthy controls that were randomly selected from the same age group as the patients. Genotyping was performed using a high-throughput allelic discrimination method using real-time PCR, and data on clinical features and demographic details were collected. Associations between genotype and breast cancer were assessed by means of logistic regression. The prevalence of Val/Val genotype was similar in patients of breast cancer and control subjects. In comparison with the Ile/Ile genotype, the Ile/Val had a borderline significantly (P= 0.06) higher risk of breast cancer (OR = 2.95, 95% CI: 0.978.96). Regarding the genotypic and allelic frequencies stratified by age and menopausal status, there were no significant associations. A significantly higher risk of breast cancer was observed among homozygous carriers of ESR1325 CC genotype and heterozygous carriers of HER-2/neu655 Ile/Val genotype (P= 0.05; adjusted OR = 4.9, 95% CI: 1.024). The association of HER-2/neu Ile655Val polymorphism and the risk of breast cancer was borderline significant with the heterozygous carrier being at higher risk. However, the frequency of different polymorphic variants varies with ethnicity. The results of this study suggest that a significant genegene interaction between ESR1325C (previously reported) and HER-2/neu Ile655Val variants may jointly contribute to a higher risk of breast cancer.

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


On the use of graph transformation in the formal specification of model interpreters Model-based development necessitates the transformation of models between different stages and tools of the design process. These transformations must be precisely, preferably formally, specified, such that end-to-end semantic interoperability is maintained. The paper introduces a graph-transformation-based technique for specifying these model transformations, gives a formal definition for the semantics of the transformation language, describes an implementation of the language, and illustrates its use through an example.

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

graph grammars
graph transformations
model-integrated computing
domain-specific modeling languages
model-driven architecture
formal specifications


West Antarctic balance calculations: Impact of flux-routing algorithm, smoothing algorithm and topography ? Balance flux and velocity calculations are important in understanding the large-scale dynamics of ice masses and their state of balance. However the grid-based (finite difference) nature of the current algorithms means that there is a variety of ways in which the balance flux and velocity can be calculated. The flux-routing algorithm, grid orientation and grid size all have an impact on the balance calculations. Previous work has relied on the assumption that the ice flow direction is orthogonal to the surface contours, with the surface having been smoothed to incorporate a representation of the longitudinal stresses within the ice. This assumption is a simplification of the gravitational driving stress equation, which relates the driving stress to the gradient of the surface slope and the ice thickness. Further, the common representation of longitudinal stresses using a fixed size smoothing filter is a simplification of the theoretical treatment of longitudinal stresses by Kamb, B., Echelmeyer, K.A. [1986. Stressgradient coupling in glacier flow: 1. longitudinal averaging of the influence of ice thickness and surface slope. Journal of Glaciology 32 (111), 267298]. This study investigates the sensitivity of the balance calculations to these issues, using the West Antarctic Ice Sheet as a case study. Significant differences in both ice stream margins and values of ice flux within them result from the algorithm choice, gridorientation and gridsize. The inclusion of a theoretically appropriate smoothing approach improves the coherence of the pattern of ice flow. The incorporation of gravitational driving stress has a small effect in comparison to practical issues such as the grid orientation and size. As higher resolution datasets (less than 5km) become available for many ice masses, there is a temptation to calculate the balance flux using the same algorithms on the finer grids. The results shown in this study suggest that the type of algorithm most commonly used is not suitable for these finer grids. The impact of the practical issues described here encourages caution in the use of grid-based balance distributions and values, especially when considering the state of balance of individual ice streams.

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

balance flux
west antarctic ice sheet
smoothing filter


An Optimal Power-Throughput Tradeoff Study for MIMO Fading Ad-Hoc Networks In this paper, we study optimal tradeoffs of achievable throughput versus consumed power in wireless ad-hoc networks formed by a collection of multiple antenna nodes. Relying on adaptive modulation and/or dynamic channel coding rate allocation techniques for multiple antenna systems, we examine the maximization of throughput under power constraints as well as the minimization of transmission power under throughput constraints. In our examination, we also consider the impacts of enforcing quality of service requirements expressed in the form of channel coding block loss constraints. In order to properly model temporally correlated loss observed in fading wireless channels, we propose the use of finite-state Markov chains. Details of fading statistics of signal-to-interference-noise ratio, an important indicator of transmission quality, are presented. Further, we objectively inspect complexity versus accuracy tradeoff of solving our proposed optimization problems at a global as oppose to a local topology level. Our numerical simulations profile and compare the performance of a variety of scenarios for a number of sample network topologies.

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

fading wireless ad-hoc networks
markov chain
power minimization
quality of service (qos)
rayleigh channel
rician channel
throughput maximization


A hybrid system for planning the development level of resort In todays world, a resort is a popular place that provides not only relaxation and recreation but also beautiful surroundings, high quality food, even facilities to exercise and do other healthy activities. Planning the development level is one of the more important processes in a resort development project. However, planners often subjectively overestimate the project or cater to the preferences of the investors, resulting in an over-developed or imbalanced development. This paper provides a system that helps the planner to search for near-optimal amenity development level. Integrating genetic algorithms and simulation, it employs a dual-loop optimization model to propose advice to be used in the planning stage. Because the complex and dynamic analysis is done by the system instead of by the planner, it speeds up the decision-making process of the planning stage.

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

resort
development level
genetic algorithms
simulation


estimation of link interference in static multi-hop wireless networks We present a measurement-based study of interference among links in a static, IEEE 802.11, multi-hop wireless network. Interference is a key cause of performance degradation in such networks. To improve, or to even estimate the performance of these networks, one must have some knowledge of which links in the network interfere with one another, and to what extent. However, the problem of estimating the interference among links of a multi-hop wireless network is a challenging one. Accurate modeling of radio signal propagation is difficult since many environment and hardware-specific factors must be considered. Empirically testing every group of links is not practical: a network with n nodes can have O ( n 2 ) links, and even if we consider only pairwise interference, we may have to potentially test O ( n 4 ) pairs. Given these difficulties, much of the previous work on wireless networks has assumed that information about interference in the network is either known, or that it can be approximated using simple heuristics. We test these heuristics in our testbed and find them to be inaccurate. We then propose a simple, empirical estimation methodology that can predict pairwise interference using only O ( n 2 ) measurements. Our methodology is applicable to any wireless network that uses omni-directional antennas. The predictions made by our methodology match well with the observed pairwise interference among links in our 22 node, 802.11-based testbed.

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

network
wireless networks
methodology
test
performance
testbed
links
heuristics
group
knowledge
practical
interference
predict
propagation

measurement
estimates
directed antennas
environments
signaling
factor
matching
hardware
model
informal
linking
multi-hop wireless network


Rainbow Induced Subgraphs in Proper Vertex Colorings Given a graph H we define rho(H) to be the minimum order of a graph G such that every proper vertex coloring of G contains a rainbow induced subgraph isomorphic to H. We give upper and lower bounds for rho(H), compute the exact value for some classes of graphs, and consider an interesting combinatorial problem connected with computation of rho(H) for paths. A part of this research has been guided by a computer search and, accordingly, some computational results are presented. A special motivation comes from research in on-line coloring.

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

rainbow
induced subgraph
vertex coloring


Histograms of optical flow for efficient representation of body motion A novel method for efficient encoding of human body motion, extracted from image sequences is presented. Optical flow field is calculated from sequential images, and the part of the flow field containing a person is subdivided into six segments. For each of the segments, a two dimensional, eight-bin histogram of optical flow is calculated. A symbol is generated, corresponding to the bin with the maximum sample count. Since the optical flow sequences before and after the temporal reference point are processed separately, twelve symbol sequences are obtained from the whole image sequence. Symbol sequences are purged of all symbol repetitions. To establish the similarity between two motion sequences, two sets of symbol sequences are compared. In our case, this is done by the means of normalized Levenshtein distance. Due to use of symbol sequences, the method is extremely storage efficient. It is also performance efficient, as it could be performed in near-realtime using the motion vectors from MPEG4 encoded video sequences. The approach has been tested on video sequences of persons entering restricted area using keycard and fingerprint reader. We show that it could be applied both to verification of person identities due to minuscule differences in their motion, and to detection of unusual behavior, such as tailgating.

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

image sequences
optical flow
levenshtein distance


A Bayesian plan-view map based approach for multiple-person detection and tracking This work proposes a novel approach for people detection and tracking in colour-with-depth sequences using a particle filtering approach. Detection and tracking are performed in plan-view maps integrating occupancy and height information with a novel plan-view map representation for colour information. Using the three maps, we propose a multiple particle filtering algorithm for people detection and tracking. The observation model proposed integrates information from the three maps so that people with different coloured clothes are not confused even when they interact at close distances. To avoid the coalescence problem when people with similar coloured clothes approach each other, the weight of particles is modified by an interaction factor that combines colour and position information. The algorithm also avoids the coalescence problem in case of total occlusion by means of an occlusion detection and recovering mechanism. Finally, a solution is proposed to improve the exponential complexity of multiple particle filters so that the algorithm proposed has linear complexity. The approach proposed has been tested in several colour-with-depth sequences where people move and interact freely in the environment. In the sequences, people walk at different distances, cross their paths causing frequent occlusions, jump, run and have close interactions such as shaking hands or embracing each other. The experimental results show that our proposal is able to detect and keep track of every person with a low error and deals with partial and total occlusions. Besides, the detection and tracking techniques presented are appropriate for large tracking problems in real-time applications since their complexity is linear, are suitable for parallel processing and allow the integration of information provided by multiple stereo vision sensors.

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

person tracking
plan-view maps
colour processing
condensation algorithm


Hybrid routing protocol with Quality of Service support for Ad Hoc Wireless Networks In Mobile Ad Hoc Networks (MANETs), mobile nodes must collaborate amongst themselves to interconnect and establish communication. Moreover, their networking characteristics highlight a new breed of unresolved routing and Quality of Service problems. In this paper we present a hybrid routing protocol with quality of service support. In this protocol, each mobile node keeps in memory not only available routes to destinations but also good routes in term of quality of service. The results obtained from simulations confirm the validity of our approach and show that our protocol clearly outperforms protocols from both the proactive and reactive type.

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


Constructing spherical curves by interpolation Based on a composite conical surface patch, we develop new simple methods for up to G2 continuous interpolation of an arbitrary sequence of points on a sphere with a specified tangent direction and curvature vector at every point. The resulting interpolation curve is the intersection of the given sphere and the composite conical surface patch. Unlike some existing methods, introduced into the method are several free parameters that can be used in subsequent interactive modification such that the resulting curves shape hits our demand, and the resulting curve can be expressed explicitly. Experiments demonstrate the method is effective and potentially useful in pattern design on sphere, sphere trim, robot, and other industrial and research fields.

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

blending
g2 continuity
spherical splines


Study of long-duration MPEG-trace segmentation methods for developing frame-size-based traffic models Texture and temporal variations in scenes, and peculiarities of MPEG compression algorithms result in very complex frame-size data sets for any long-duration variable bit rate (VBR) video. A major hurdle in capturing the statistical behavior of such a data trace can be removed by segmentation of all frames into an appropriate number of analytically characterizable classes. However, video-trace segmentation techniques, particularly those which also enable preserving periodicity of group of pictures (GOP) in the modeled data, are lacking in the literature. In this paper, we propose and evaluate few techniques for segmenting frame-size data sets in any long-duration video trace. The proposed techniques partition the group of pictures in a video into size-based groups called shot-classes. Frames in each shot-class have three data-setsone each for intra (I-), bi-directional (B-), and predictive (P-) type frames. We have evaluated the performance of the proposed segmentation techniques by modeling each of I-, B-, and P-type frame in each shot-class by a Gamma distribution. Accuracy and usefulness of the proposed segmentation methods in building frame-size traffic models have been evaluated by QQ plots and the leaky-bucket simulation study. The results reveal that one of the segmentation techniques is very effective in characterizing the frame-size data behavior in a long-duration VBR video.

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

variable bit rate video
frame-size traffic model


Propagation of measurement noise through backprojection reconstruction in electrical impedance tomography A framework to analyze the propagation of measurement noise through backprojection reconstruction algorithms in electrical impedance tomography (EIT) is presented. Two measurement noise sources were considered: noise in the current drivers and in the voltage detectors. The influence of the acquisition system architecture (serial/semi-parallel) is also discussed. Three variants of backprojection reconstruction are studied: basic (unweighted), weighted and exponential backprojection. The results of error propagation theory have been compared with those obtained from simulated and experimental data. This comparison shows that the approach provides a good estimate of the reconstruction error variance. It is argued that the reconstruction error in EIT images obtained via backprojection can be approximately modeled as a spatially nonstationary Gaussian distribution. This methodology allows us to develop a spatial characterization of the reconstruction error in EIT images.

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

backprojection reconstruction
electrical impedance tomography
error propagation theory


Parametric model discrimination for heavily censored survival data Simultaneous discrimination among various parametric lifetime models is an important step in the parametric analysis of survival data. We consider a plot of the skewness versus the coefficient of variation for the purpose of discriminating among parametric survival models. We extend the method of Cox & Oakes from complete to censored data by developing an algorithm based on a competing risks model and kernel function estimation. A by-product of this algorithm is a nonparametric survival function estimate.

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


Improving Energy Efficiency for Mobile Media Cloud via Virtual Machine Consolidation Mobile media applications are on the rise due to the explosive popularity of mobile devices. Advances in mobile media cloud (MMC) make it a promising solution to serve those huge multimedia applications. In MMC, virtualization is adopted to allocate resources elastically from a shared resource pool. Therefore, effective virtual machine (VM) consolidation is of paramount importance to maximize energy efficiency. In this paper, we consider a scenario that mobile media cloud performs video streaming and transcoding for viewers with different mobile devices. We formulate the VM consolidation problem as a mixed integer linear programming. Under this framework, the minimum energy consumption and the number of physical machines (PMs) in operation are derived. Based on these analytical results, for homogeneous media cloud, we develop an approximation algorithm for VM consolidation and placement which jointly considers CPU and bandwidth constraints. For heterogeneous media cloud, we derive an upper and a lower bound of the number of PMs and their energy consumption. Trace-driven simulations demonstrate that our proposed algorithm significantly reduces energy consumption and the number of PMs used.

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


Simple, efficient mixed solid element for accurate analysis of local effects in laminated and sandwich composites A mixed, eight-node solid element is developed with the aim to accurately and efficiently capture local stresses in composites. The nodal degrees of freedom are the three displacements and the three interlaminar stresses. Characteristic features, C0, tri-linear, serendipity shape functions are used to interpolate these quantities across the element volume. With this choice, the intraelement stress fields satisfy the equilibrium equations in integral form. Integration is exact. It is carried out by a symbolic calculus tool. To test the element performances, the intricate stress fields of thick sandwich composites with undamaged and damaged face layers, piezoelectrically actuated beams, thermally loaded laminates and close to a two-material wedge singularity are investigated. The element appears robust, stable and rather accurate using reasonably fine meshes. Compared to displacement-based counterpart elements, the computational effort is not larger.

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

3d stresses analysis of damaged composites


Non-linear robust identification using evolutionary algorithms Application to a biomedical process This work describes a new methodology for robust identification (RI), meaning the identification of the parameters of a model and the characterization of uncertainties. The alternative proposed handles non-linear models and can take into account the different properties demanded by the model. The indicator that leads the identification process is the identification error (IE), that is, the difference between experimental data and model response. In particular, the methodology obtains the feasible parameter set (FPS, set of parameter values which satisfy a bounded IE) and a nominal model in a non-linear identification problem. To impose different properties on the model, several norms of the IE are used and bounded simultaneously. This improves the model quality, but increases the problem complexity. The methodology proposes that the RI problem is transformed into a multimodal optimization problem with an infinite number of global minima which constitute the FPS. For the optimization task, a special genetic algorithm (epsilon-GA), inspired by Multiobjective Evolutionary Algorithms, is presented. This algorithm characterizes the FPS by means of a discrete set of models well distributed along the FPS. Finally, an application for a biomedical model which shows the blockage that a given drug produces on the ionic currents of a cardiac cell is presented to illustrate the methodology. (C) 2008 Elsevier Ltd. All rights reserved.

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

robust identification
multimodal optimization
evolutionary algorithms

multiobjective optimization
biomedical processes


Experimental performance of shared RSA modulus generation Many distributed protocols require the participants to have secret shares of an RSA modulus in order to perform distributed cryptographic computations. Until recently, a trusted party was required to generate and distribute these secret shares before the start of the protocol. Recently, Boneh and Franklin introduced a protocol whereby participants could themselves generate the secret shares without revealing any information about their shares to each other. We experimentally evaluate the performance of their protocol and we recommend good choices for certain parameters of the protocol.

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

public key cryptography
distributed computation
secure multiparty computation


Averaging and Metropolis Iterations For Positron Emission Tomography Iterative positron emission tomography (PET) reconstruction computes projections between the voxel space and the lines of response (LOR) space, which are mathematically equivalent to the evaluation of multi-dimensional integrals. The dimension of the integration domain can be very high if scattering needs to be compensated. Monte Carlo (MC) quadrature is a straightforward method to approximate high-dimensional integrals. As the numbers of voxels and LORs can be in the order of hundred millions and the projection also depends on the measured object, the quadratures cannot be precomputed, but Monte Carlo simulation should take place on-the-fly during the iterative reconstruction process. This paper presents modifications of the maximum likelihood, expectation maximization (ML-EM) iteration scheme to reduce the reconstruction error due to the on-the-fly MC approximations of forward and back projections. If the MC sample locations are the same in every iteration step of the ML-EM scheme, then the approximation error will lead to a modified reconstruction result. However, when random estimates are statistically independent in different iteration steps, then the iteration may either diverge or fluctuate around the solution. Our goal is to increase the accuracy and the stability of the iterative solution while keeping the number of random samples and therefore the reconstruction time low. We first analyze the error behavior of ML-EM iteration with on-the-fly MC projections, then propose two solutions: averaging iteration and Metropolis iteration. Averaging iteration averages forward projection estimates during the iteration sequence. Metropolis iteration rejects those forward projection estimates that would compromise the reconstruction and also guarantees the unbiasedness of the tracer density estimate. We demonstrate that these techniques allow a significant reduction of the required number of samples and thus the reconstruction time. The proposed methods are built into the Teratomo system.

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

expectation maximization (ml-em) reconstruction


On the failure of fixed-point theorems for chain-complete lattices in the effective topos We show that in the effective topos there is a chain-complete distributive lattice with a monotone and progressive endomap which does not have a fixed point. An immediate consequence of this is that both Tarski's theorem for chain-complete posers and the Bourbaki-Witt theorem have no constructive (topos-valid) proofs. (c) 2012 Elsevier B.V. All rights reserved.

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

bourbaki-witt theorem
tarski's theorem
chain-complete posets
fixed points
constructive logic


Improved branching disjunctions for branch-and-bound: An analytic center approach A new approach to generate branching disjunctions based on the shape of the polyhedron. Uses the analytic center concept and Dikins ellipsoid from interior-point methods. Finds the minimum-width disjunction by solving a quadratic problem. Tested on multidimensional knapsack problems and MIPLIB instances. Shown to perform well. Tested within a branch-and-bound setting that is entirely based on interior-point concepts.

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

interior-point methods
integer programming
branch-and-bound
generalized branching


on semi-supervised clustering via multiobjective optimization Semi-supervised classification uses aspects of both unsupervised and supervised learning to improve upon the performance of traditional classification methods. Semi-supervised clustering , in particular, explicitly integrates both information about the data distribution and about class memberships into the clustering process. In this paper, the potential of a multiobjective formulation of the semi-supervised clustering problem is explored, and two evolutionary multiobjective approaches to the problem are outlined. Experimental results demonstrate practical performance benefits of this methodology, including an improved classification performance and an increased robustness towards annotation errors.

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

multiobjective clustering
semi-supervised learning
semi-supervised clustering
multiobjective machine learning


H? filtering for networked systems with partly known distribution transmission delays This paper studies the H? filtering problem for a class of discrete-time networked systems with partly known distribution transmission delays. It is assumed that the random sensor-filter delay satisfies Markovian characteristics, but the transition probabilities of the delay transferring from one value to others are partly known. A novel measurement model is proposed to reflect the random delay of the transmission modes and the resulting filtering error system is modeled as a Markovian jump system (MJS) with multiple modes and state delay. Sufficient conditions are derived for the filtering error system to be stochastically stable and ensure a prescribed H? disturbance attenuation level bound by using mode-dependent Lyapunov functional approach. Based on the derived conditions, a design procedure for the H? filter is also presented. A numerical example is provided to show the design process of the filter and the effectiveness of the proposed method.

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

networked system
h? filtering
random measurement delay
system augmentation
linear matrix inequality (lmi)


Human Identification Using Temporal Information Preserving Gait Template Gait Energy Image (GEI) is an efficient template for human identification by gait. However, such a template loses temporal information in a gait sequence, which is critical to the performance of gait recognition. To address this issue, we develop a novel temporal template, named Chrono-Gait Image (CGI), in this paper. The proposed CGI template first extracts the contour in each gait frame, followed by encoding each of the gait contour images in the same gait sequence with a multichannel mapping function and compositing them to a single CGI. To make the templates robust to a complex surrounding environment, we also propose CGI-based real and synthetic temporal information preserving templates by using different gait periods and contour distortion techniques. Extensive experiments on three benchmark gait databases indicate that, compared with the recently published gait recognition approaches, our CGI-based temporal information preserving approach achieves competitive performance in gait recognition with robustness and efficiency.

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

computer vision
biometric authentication
pattern recognition


fast implementation of depth contours using topological sweep The concept of location depth was introduced in statistics as a way to extend the univariate notion of ranking to a bivariate configuration of data points. It has been used successfully for robust estimation, hypothesis testing, and graphical display. These require the computation of depth regions, which form a collection of nested polygons. The center of the deepest region is called the Tukey median. The only available implemented algorithms for the depth contours and the Tukey median are slow, which limits their usefulness. In this paper we describe an optimal algorithm which computes all depth contours in &Ogr; ( n 2 ) time and space, using topological sweep of the dual arrangement of lines. Once the contours are known, the location depth of any point is computed in &Ogr; (log 2 n ) time. We provide fast implementations of these algorithms to allow their use in everyday statistical practice.

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

point statistics use space region arrangement computation implementation concept data paper algorithm robust ranking

estimates locatability optimality test collect configurability timing graphics contouring practical


Forecasting enrollments using automatic clustering techniques and fuzzy logical relationships In recent years, some researchers focused on the research topic of using fuzzy time series to handle forecasting problems. In this paper, we present a new method to forecast enrollments based on automatic clustering techniques and fuzzy logical relationships. First, we present an automatic clustering algorithm for clustering historical enrollments into intervals of different lengths. Then, each obtained interval will be divided into p sub-intervals, where p?1 p ? 1 . Based on the new obtained intervals and fuzzy logical relationships, we present a new method for forecasting the enrollments of the University of Alabama. The proposed method gets a higher average forecasting accuracy rate than the existing methods.

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

automatic clustering techniques
fuzzy time series
fuzzy logical relationships


Using and managing multiple passwords: A week to a view Security policies are required that protect information from unauthorised access, and also respect challenges users face in creating, and particularly managing, increasing numbers of passwords. This paper investigates real password use in the context of daily life. It presents the results of an empirical study where participants completed a password diary over 7 days, followed by debrief interviews to gain further knowledge and understanding of user behaviour. The results reported relate to how many passwords are in use, the types of passwords participants created, the relationships between different passwords and to sensitive services, how participants retrieved their passwords and finally, the different strategies adopted by users in their management of passwords. The paper concludes by providing a high level set of password guidelines, along with suggestions for mechanisms to support creating, encoding, retrieving and executing multiple passwords. (C) 2011 Elsevier B.V. All rights reserved.

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


Regular expression-based learning to extract bodyweight values from clinical notes REDEx accurately extracted weight from outpatient primary care notes. Extracted values were reliable (highly correlated with values from structured field). Unique values (2 per individual per year) were identified. This method can reduce missing/mistimed values in cohort identification. REDEx is flexible and can be retrained to textual expressions.

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

natural language processing
text classification


Solving multi-objective routing and wavelength assignment in WDM network using hybrid evolutionary computation approach Routing and wavelength assignment (RWA) is a well-known issue in wavelength division multiplexing (WDM) optical networks. In this paper, we present RWA design for WDM networks by considering multiple design objectives which are maximizing the number of traffic demands to be served and minimizing the number of wavelength channels to be assigned. A hybrid evolutionary computation approach consisting of genetic algorithm for routing allocation with minimum degree first for wavelength assignment (GA-MDF) and the fast non-dominated sorting genetic algorithm (NSGA-II) to search for non-dominated solutions is applied for solving the multi-objective RWA network design problem. The hybrid evolutionary algorithm is used as a meta-heuristic technique for obtaining good solutions for various problem sizes. The obtained results are provided as candidate choices or non-dominated front. We compare the simulation results obtained from the NSGA-II with those obtained from the traditional Weighted-Sum approach. Numerical results show that our hybrid evolutionary computation approach is effective in solving the multi-objective RWA problem. The GA-MDF can outperform the FAR-FF method in both design objectives. In addition, the solutions from the NSGA-II are more diverse on the multi-objective space than those of the Weighted-Sum method. We also apply a Pruned mechanism to help cutting off numerous non-dominated solutions for making decision on the final solution. (C) 2010 Elsevier B.V. All rights reserved.

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

routing and wavelength assignment
wdm network


teaching programming: a new approach based on analysis skills A new approach is described to the teaching of introductory computer programming and computer science (the CS1 course). The approach is based on a new view of what programming is fundamentally about. The central feature of the approach is the teaching of skills in program analysis along with the traditional emphasis on skills in program synthesis . The approach was class tested in an earlier version in 1986, and the difficulties encountered in the class test led to two supporting changes in the course content: (1) data structures are introduced at the beginning of the course, and (2) the concept of program state is introduced as a key element in understanding programs.

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

computer science
program
test
analysis
concept
teaching
version
feature
computer programming
class

understandability contention skill change


Ectropy of diversity measures for populations in Euclidean space Measures to evaluate the diversity of a set of points (population) in Euclidean space play an important role in a variety of areas of science and engineering. Well-known measures are often used without a clear insight into their quality and many of them do not appropriately penalize populations with a few distant groups of collocated or closely located points. To the best of our knowledge, there is a lack of rigorous criteria to compare diversity measures and help select an appropriate one. In this work we define a mathematical notion of ectropy for classifying diversity measures in terms of the extent to which they tend to penalize point collocation, we investigate the advantages and disadvantages of several known measures and we propose some novel ones that exhibit a good ectropic behavior. In particular, we introduce a quasi-entropy measure based on a geometric covering problem, three measures based on discrepancy from uniform distribution and one based on Euclidean minimum spanning trees. All considered measures are tested and compared on a large set of random and structured populations. Special attention is also devoted to the complexity of computing the measures. Most of the novel measures compare favorably with the classical ones in terms of ectropy. The measure based on Euclidean minimum spanning trees turns out to be the most promising one in terms of the tradeoff between the ectropic behavior and the computational complexity.

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

population diversity measure
klees measure
minimum spanning tree
singular values


Approximation of a variable density cloud of points by shrinking a discrete membrane This paper describes a method to obtain a closed surface that approximates a general 3D data point set with nonuniform density. Aside from the positions of the initial data points, no other information is used. Particularly, neither the topological relations between the points nor the normal to the surface at the data points are needed. The reconstructed surface does not exactly interpolate the initial data points, but approximates them with a bounded maximum distance. The method allows one to reconstruct closed surfaces with arbitrary genus and closed surfaces with disconnected shells.

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

scattered data points
surface approximation
voxelization
discrete geometry


Workforce planning and deployment for a hospital reservation call center with abandonment cost and multiple tasks We consider a hospital reservation call center where operators handle multiple tasks. We take into account operator labor costs, caller waiting costs, and abandonment costs for lost calls. Instead of relying on the traditional method of queueing theory for call center management, we present a method that obtains expected caller waiting time and expected abandonment rate directly by introducing the inbound-load parameter. We develop a framework that combines workforce planning and operator deployment for a mixed call center in a single mathematical programming model. This paper also demonstrates how the proposed methodology can be applied in practice, with a case study based on actual operational data. Our primary conclusion is that the method presented in this research can significantly reduce both expected total cost (by 55.1% in our case study) and abandonment rate (from 15% to 2.1% in our case study). In addition, we demonstrate, using a sensitivity analysis, that our methodology will be more effective in an environment where the unit penalty cost of an abandoned call is relatively high among competitive hospitals. (C) 2013 Elsevier Ltd. All rights reserved.

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

workforce planning
deployment
call center management
abandonment cost
multiple tasks
mathematical programming


Convex and Semi-Nonnegative Matrix Factorizations We present several new variations on the theme of nonnegative matrix factorization (NMF). Considering factorizations of the form X = FG(T), we focus on algorithms in which G is restricted to containing nonnegative entries, but allowing the data matrix X to have mixed signs, thus extending the applicable range of NMF methods. We also consider algorithms in which the basis vectors of F are constrained to be convex combinations of the data points. This is used for a kernel extension of NMF. We provide algorithms for computing these new factorizations and we provide supporting theoretical analysis. We also analyze the relationships between our algorithms and clustering algorithms, and consider the implications for sparseness of solutions. Finally, we present experimental results that explore the properties of these new methods.

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

nonnegative matrix factorization
clustering


Fast and reliable performance evaluation in mobile wireless networks using dynamic simulations This paper presents statistical methods to enhance dynamic simulations in mobile networks. The aim is to perform reliable (unbiased) and fast evaluation of QoS indicators such as blocking and dropping rates. To do so, we adopt a trajectory splitting (TS) method that splits the path of the simulated stochastic process into multiple copies for determined configurations, thus focusing on configurations for which communication problems are likely to occur. We show that this method significantly reduces the variance of the estimators of both blocking and dropping probabilities, and hence reduces simulation times for the same precision. In a real network dynamic simulation, we propose an algorithm that automatically checks that the network has reached its steady state distribution and eliminates the bias due to the initial stabilization samples. We then isolate stations of interest with their most interfering neighbors and show that applying TS to these regions of interest leads to a very significant reduction of the simulation times.

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

performance evaluation
dynamic simulation
mobile networks
qos

variance reduction
convergence diagnostic
interference matrices


Learning complex action models with quantifiers and logical implications Automated planning requires action models described using languages such as the Planning Domain Definition Language (PDDL) as input, but building action models from scratch is a very difficult and time-consuming task, even for experts. This is because it is difficult to formally describe all conditions and changes, reflected in the preconditions and effects of action models. In the past, there have been algorithms that can automatically learn simple action models from plan traces. However, there are many cases in the real world where we need more complicated expressions based on universal and existential quantifiers, as well as logical implications in action models to precisely describe the underlying mechanisms of the actions. Such complex action models cannot be learned using many previous algorithms. In this article, we present a novel algorithm called LAMP (Learning Action Models from Plan traces), to learn action models with quantifiers and logical implications from a set of observed plan traces with only partially observed intermediate state information. The LAMP algorithm generates candidate formulas that are passed to a Markov Logic Network (MLN) for selecting the most likely subsets of candidate formulas. The selected subset of formulas is then transformed into learned action models, which can then be tweaked by domain experts to arrive at the final models. We evaluate our approach in four planning domains to demonstrate that LAMP is effective in learning complex action models. We also analyze the human effort saved by using LAMP in helping to create action models through a user study. Finally, we apply LAMP to a real-world application domain for software requirement engineering to help the engineers acquire software requirements and show that LAMP can indeed help experts a great deal in real-world knowledge-engineering applications. (C) 2010 Elsevier By. All rights reserved.

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

action model learning
machine learning
knowledge engineering


Allowing each node to communicate only once in a distributed system: shared whiteboard models In this paper we study distributed algorithms on massive graphs where links represent a particular relationship between nodes (for instance, nodes may represent phone numbers and links may indicate telephone calls). Since such graphs are massive they need to be processed in a distributed way. When computing graph-theoretic properties, nodes become natural units for distributed computation. Links do not necessarily represent communication channels between the computing units and therefore do not restrict the communication flow. Our goal is to model and analyze the computational power of such distributed systems where one computing unit is assigned to each node. Communication takes place on a whiteboard where each node is allowed to write at most one message. Every node can read the contents of the whiteboard and, when activated, can write one small message based on its local knowledge. When the protocol terminates its output is computed from the final contents of the whiteboard. We describe four synchronization models for accessing the whiteboard. We show that message size and synchronization power constitute two orthogonal hierarchies for these systems. We exhibit problems that separate these models, i.e., that can be solved in one model but not in a weaker one, even with increased message size. These problems are related to maximal independent set and connectivity. We also exhibit problems that require a given message size independently of the synchronization model.

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

distributed computing
local computation
graph properties
bounded communication


Conformational analysis of piperazine and piperidine analogs of GBR 12909: stochastic approach to evaluating the effects of force fields and solvent Analogs of the flexible dopamine reuptake inhibitor; GBR 12909 (1), may have potential utility in the treatment of cocaine abuse. As a first step in the 3D-QSAR modeling of the dopamine transporter (DAT)/serotonin transporter (SERT) selectivity of these compounds, we carried out conformational analyses of two analogs of 1: a piperazine (2) and a related piperidine (3). Ensembles of conformers consisting of local minima on the potential energy surface of the molecule were generated in the vacuum phase and in implicit solvent by random search conformational analysis using the Tripos and MMFF94 force fields. Some differences were noted in the conformer populations due to differences in the treatment of the tertiary amine nitrogen and ether oxygen atom types by the force fields. The force fields also differed in their descriptions of internal rotation around the C(sp(3))-O(sp(3)) bond proximal to the bisphenyl moiety. Molecular orbital calculations at the HF/6-31G(d) and B3LYP/6-31G(d) levels of C-O internal rotation in model compound (5), designed to model the effect of the proximity of the bisphenyl group on C-O internal rotation, showed a broad region of low energy between -60 degrees to 60 degrees with minima at both -60 degrees and 30 degrees and a low rotational barrier at 0 degrees, in closer agreement with the MIMFF94 results than the Tripos results. Molecular mechanics calculations on model compound (6) showed that the MMFF94 force field was much more sensitive than the Tripos force field to the effects of the bisphenyl moiety on C-O internal rotation.

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

conformational analysis
gbr 12909
dopamine reuptake inhibitor
molecular mechanics
molecular orbital
tripos force field
mmff94 force field

dopamine transport
stochastic search
conformer population


A pseudo-distance routing (PDR) algorithm for mobile ad-hoc networks Previous routing algorithms for mobile ad-hoc networks (MANETs) have focused on finding short-distance path(s) between communicating nodes. However, due to the dynamic and unreliable communication nature of MANETs, previously determined paths can easily become disconnected. Although dynamic routing can be used to circumvent this problem, determining a new route each time a packet needs to be sent involves a lot of overhead. An alternative form of dynamic routing involves maintaining valid routes in routing tables, which can be dynamically updated whenever network changes are detected. This paper proposes a new routing algorithm, referred to as pseudo-distance routing (PDR), that supports efficient routing table maintenance and dynamic routing based on such routing tables.

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


VisualLISA: A Visual Environment to Develop Attribute Grammars The focus of this paper is on crafting a new visual language for attribute grammars (AGs), and on the development of the associated programming environment. We present a solution for rapid development of VisualLISA editor using DEViL. DEViL uses traditional attribute grammars, to specify the language's syntax and semantics, extended by visual representations to be associated with grammar symbols. From these specifications a visual programming environment is automatically generated. In our case, the environment allows us to edit a visual description of an AG that is automatically translated into textual notations, including an XML-based representation for attribute grammars (XAGra), and is intended to be helpful for beginners and rapid development of small AGs. XAGra allows us to use VisualLISA with other compiler-compiler tools.

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

attribute grammar
visual languages
xml dialect


Managing Burstiness and Scalability in Event-Driven Models on the SpiNNaker Neuromimetic System Neural networks present a fundamentally different model of computation from the conventional sequential digital model, for which conventional hardware is typically poorly matched. However, a combination of model and scalability limitations has meant that neither dedicated neural chips nor FPGA's have offered an entirely satisfactory solution. SpiNNaker introduces a different approach, the "neuromimetic" architecture, that maintains the neural optimisation of dedicated chips while offering FPGA-like universal configurability. This parallel multiprocessor employs an asynchronous event-driven model that uses interrupt-generating dedicated hardware on the chip to support real-time neural simulation. Nonetheless, event handling, particularly packet servicing, requires careful and innovative design in order to avoid local processor congestion and possible deadlock. We explore the impact that spatial locality, temporal causality and burstiness of traffic have on network performance, using tunable, biologically similar synthetic traffic patterns. Having established the viability of the system for real-time operation, we use two exemplar neural models to illustrate how to implement efficient event-handling service routines that mitigate the problem of burstiness in the traffic. Extending work published in ACM Computing Frontiers 2010 with on-chip testing, simulation results indicate the viability of SpiNNaker for large-scale neural modelling, while emphasizing the need for effective burst management and network mapping. Ultimately, the goal is the creation of a library-based development system that can translate a high-level neural model from any description environment into an efficient SpiNNaker instantiation. The complete system represents a general-purpose platform that can generate an arbitrary neural network and run it with hardware speed and scale.

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

asynchronous burst network universal neural multiprocessor traffic

event-driven interconnection real-time characterisation


Monitoring pilot "Situation Awareness" Pilot error remains the major cause of aircraft accidents. The lack of Situation Awareness (SA), even amongst experienced pilots, is one of the primary reasons for pilot error. It is important to ensure that pilots are able to maintain a high level of SA before they act as members of a flight crew. A pilot's SA can be assessed by monitoring pilot behavior using observations of pilot eye movement. In this paper we discuss a rule-based approach to assess novice pilots' SA against a baseline. A recent experiment confirmed there is a measurable difference between the eye movement of an experienced pilot and the eye movement of several novice pilots. Initially, an expert pilot's eye movement was recorded using an eye tracker device in order to set the baseline. A Gaze Analyzer was used to derive relevant information from eye movement data. After consulting a Subject Matter Expert (SME), a rule-based system was created to monitor the pilot's behavior. The data was analyzed to identify behavioral patterns in order to associate the pilots' level of SA with their mode of attention distribution (fixation). Novice pilot's eye movement data was compared with an expert pilot's eye movement data using an inference engine.

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


Modelling regional input markets with numerous processing plants: The case of green maize for biogas production in Germany The location of first generation processing plants for biogas using bulky inputs is a prominent example of locational decisions of plants that face high per unit transport costs of feedstock and simultaneously depend to a large extent on feedstock availability. Modelling the resulting regional feedstock markets then requires a spatially explicit representation of demand. With production capacities of plants small in comparison to market size, large numbers of possible type-location combinations need to be considered, requiring considerable computation time under existing integer programming-based approaches. Therefore, in this paper we aim to present an alternative, faster and more flexible iterative solution approach to simulate location decisions for processing plants. And with greater flexibility, this approach is able to take into account spatially heterogeneous transport costs depending on total demand. The approach is implemented in a modelling framework for biogas production from green maize in Germany, which currently accounts for ca. five per cent of Germanys agricultural area. By modifying green maize prices, demand functions are derived and intersected with regional supply functions from an agricultural model to simulate market clearing prices and quantities. The application illustrates that our approach efficiently simulates markets characterised by small-scale demand units and high, spatially heterogeneous transport costs.

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

competitive facility location
biomass transportation


Constrained node-weighted Steiner tree based algorithms for constructing a wireless sensor network to cover maximum weighted critical square grids Deploying minimum sensors to construct a wireless sensor network such that critical areas in a sensing field can be fully covered has received much attention recently. In previous studies, a sensing field is divided into square grids, and the sensors can be deployed only in the center of the grids. However, in reality, it is more practical to deploy sensors in any position in a sensing field. Moreover, the number of sensors may be limited due to a limited budget. This motivates us to study the problem of using limited sensors to construct a wireless sensor network such that the total weight of the covered critical square grids is maximized, termed the weighted-critical-square-grid coverage problem, where the critical grids are weighted by their importance. A reduction, which transforms our problem into a graph problem, termed the constrained node-weighted Steiner tree problem, is proposed and used to solve our problem. In addition, three heuristics, including the greedy algorithm (GA), the group-based algorithm (GBA), and the profit-based algorithm (PBA), are proposed for the constrained node-weighted Steiner tree problem. Simulation results show that the proposed reduction with the PBA provides better performance than the others.

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

wireless sensor network
coverage problem


Predicting sentencing outcomes with centrality measures Despite their importance for stakeholders in the criminal justice system, few methods have been developed for determining which criminal behavior variables will produce accurate sentence predictions. Some approaches found in the literature resort to techniques based on indirect variables, but not on the social network behavior with exception of the work of Baker and Faulkner [ASR 58: 837860, 1993]. Using information on the Caviar Network narcotics trafficking group as a real-world case, we attempt to explain sentencing outcomes employing the social network indicators. Specifically, we report the ability of centrality measures to predict a) the verdict (innocent or guilty) and b) the sentence length in years. We show that while the set of indicators described by Baker and Faulkner yields good predictions, introduction of the additional centrality measures generates better predictions. Some ideas for orienting future research on further improvements to sentencing outcome prediction are discussed.

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


Behaviour of the thermal impedance of buried power cables The ampacity of power cables depends heavily on their ability to diffuse their resistive heating to their environment. This ability however depends in turn on the characteristics of the material surrounding the power cable. In this work, the concept of thermal impedance is utilised in order to determine the thermal properties of a power cable buried in earth with respect to the burial depth. To that purpose, a theoretical analysis is conducted concerning the calculation of the thermal impedance for the problem under study. Moreover, an experimental setup is used in order to test the remarks obtained by the theoretical analysis concerning the thermal behaviour of the cable.

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


Selective wet etching of Si3N4/SiO2 in phosphoric acid with the addition of fluoride and silicic compounds ? Selective wet etching of Si3N4 to SiO2 in H3PO4. Both etch rate and selectivity strongly related to the amount of fluorine added in H3PO4. Etch selectivity modulated by addition of fluoride and silicic compounds to H3PO4. Etch selectivity greater than 104 with addition of Si(OH)4 in the presence of NH4F and NH4HF2.

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

selective etching
reaction mechanism
silicon nitride


Fuzzy AHP-based multicriteria decision making systems using particle swarm optimization This paper presents a fuzzy optimization model to solve multicriteria decision making (MCDM) systems based on a fuzzy analytic hierarchy process (fuzzy AHP). To deal with the imprecise judgments of decision makers, a fuzzy AHP decision making model is proposed as an evaluation tool, where the expert's comparison judgments are translated into fuzzy numbers. Unlike the conventional fuzzy AHP methods, the proposed method drives exact weights from consistent and inconsistent fuzzy comparison matrices, which eliminate the need of additional aggregation and ranking procedures. The proposed method transforms a fuzzy prioritization problem into a constrained nonlinear optimization model. An improved particle swarm optimization (PSO) is applied to solve the optimization model as a nonlinear system of equations. Several illustrative examples using existing fuzzy AHP methods are given to demonstrate the effectiveness of the proposed method. (C) 2011 Elsevier Ltd. All rights reserved.

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


duration properties over real time system designs Constraints on the accumulated sojourn time at particular system states are among the possible requirements for a real-time system. These requirements are called duration properties. The need to predict temporal behavior of critical real-time systems has encouraged the development of a useful collection of results for run-time scheduling as well as an interesting set of formal automatic techniques based on model-checking. However, no automatic technique directly supports the verification of duration requirements over physical designs of real-time software. In [6] it is presented an approach that applies known scheduling theory to automatically derive simple and compositional formal models based on timed automata [1]. In this article, we combine that modeling method with a conservative algorithm that extends [5] to check duration properties over the resulting timed automata.

B I O O O O O 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 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 B I


utilizing web server middleware for development environments and student projects Teaching and learning web development is challenging today because of multiple factors including complexity, scale and security. As these challenges have grown through the years of the web, educators have been required to keep up with them in order to provide web-development education that has fidelity with practice. At Southern Polytechnic, we have been trying to keep abreast with a convenient development environment that is suitable for student use. This poster identifies and analyzes the major factors involved in deciding on a platform and recommends some freely available middleware suitable for web development environments and student projects.

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

instructional technologies
nontraditional students
laboratory experience
student development platform
distance learning


Intentions, practices and aspirations: Understanding learning in design This paper is about learning in design and how can we measure this learning. The work reported here is based on a study of the actual practice of procurement, design and construction of a number of clients who repeatedly commission work of a similar nature. The paper sets out the background of a project entitled LEAF (Learning from ExperienceApplying Feedback) which developed a generic model to assist organisations in understanding their situation. The discussion develops the LEAF evaluation model and explains its use describing all its parameters.

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

ipa (intentions
and aspirations)
design process
architectural design


Bayesian graphical models for software testing This paper describes a new approach to the problem of software testing. The approach is based on Bayesian graphical models and presents formal mechanisms for the logical structuring of the software testing problem, the probabilistic and statistical treatment of the uncertainties to be addressed, the test design and analysis process, and the incorporation and implication of test results. Once constructed, the models produced are dynamic representations of the software testing problem. They may be used to drive test design, answer what-if questions, and provide decision support to managers and testers. The models capture the knowledge of the software tester for further use. Experiences of the approach in case studies are briefly discussed.

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

bayesian graphical models
software testing
test design

expert judgment
knowledge capture
software reliability
statistical methods


a quantitative analysis of the speedup factors of fpgas over processors The speedup over a microprocessor that can be achieved by implementing some programs on an FPGA has been extensively reported. This paper presents an analysis, both quantitative and qualitative, at the architecture level of the components of this speedup. Obviously, the spatial parallelism that can be exploited on the FPGA is a big component. By itself, however, it does not account for the whole speedup.In this paper we experimentally analyze the remaining components of the speedup. We compare the performance of image processing application programs executing in hardware on a Xilinx Virtex E2000 FPGA to that on three general-purpose processor platforms: MIPS, Pentium III and VLIW. The question we set out to answer is what is the inherent advantage of a hardware implementation over a von Neumann platform. On the one hand, the clock frequency of general-purpose processors is about 20 times that of typical FPGA implementations. On the other hand, the iteration level parallelism on the FPGA is one to two orders of magnitude that on the CPUs. In addition to these two factors, we identify the efficiency advantage of FPGAs as an important factor and show that it ranges from 6 to 47 on our test benchmarks. We also identify some of the components of this factor: the streaming of data from memory, the overlap of control and data flow and the elimination of some instruction on the FPGA. The results provide a deeper understanding of the tradeoff between system complexity and performance when designing Configurable SoC as well as designing software for CSoC. They also help understand the one to two orders of magnitude in speedup of FPGAs over CPU after accounting for clock frequencies.

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


Iterative fast orthogonal search algorithm for MDL-based training of generalized single-layer networks The generalized single-layer network (GSLN) architecture, which implements a sum of arbitrary basis functions defined on its inputs, is potentially a flexible and efficient structure for approximating arbitrary nonlinear functions. A drawback of GSLNs is that a large number of weights and basis functions may be required to provide satisfactory approximations. In this paper, we present a new approach in which an algorithm known as iterative fast orthogonal search (IFOS) is coupled with the minimum description length (MDL) criterion to provide automatic structure selection and parameter estimation for GSLNs. The resulting algorithm, dubbed IFOSMDL, performs both network growth and pruning to construct sparse GSLNs from potentially large spaces of candidate basis functions.

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

fast orthogonal search
minimum description length

orthogonal least squares
radial basis function
volterra network
generalized single-layer network
generalized linear discriminant
mackeyglass


Continuous Archimedean t-norms and their bounds Upper and lower bounds in the class of continuous Archimedean t-norms are studied. The existence of strict (nilpotent) bounds of finite families of strict (nilpotent) t-norms is shown in a constructive way, based on the additive generators of the corresponding t-norms. In general, a nilpotent lower bound and a strict upper bound of a finite system of any continuous Archimedean t-norms can be found. Some examples and some applications are given. By the duality, similar results for bounds of continuous Archimedean t-conorms can be derived. (C) 2001 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

additive generator
nilpotent t-norm
strict t-norm
subadditive function
superadditive function


An efficient measure of compactness for two-dimensional shapes and its application in regionalization problems A measure of shape compactness is a numerical quantity representing the degree to which a shape is compact. Ways to provide an accurate measure have been given great attention due to its application in a broad range of GIS problems, such as detecting clustering patterns from remote-sensing images, understanding urban sprawl, and redrawing electoral districts to avoid gerrymandering. In this article, we propose an effective and efficient approach to computing shape compactness based on the moment of inertia (MI), a well-known concept in physics. The mathematical framework and the computer implementation for both raster and vector models are discussed in detail. In addition to computing compactness for a single shape, we propose a computational method that is capable of calculating the variations in compactness as a shape grows or shrinks, which is a typical application found in regionalization problems. We conducted a number of experiments that demonstrate the superiority of the MI over the popular isoperimetric quotient approach in terms of (1) computational efficiency; (2) tolerance of positional uncertainty and irregular boundaries; (3) ability to handle shapes with holes and multiple parts; and (4) applicability and efficacy in districting/zonation/regionalization problems.

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

moment of inertia
compactness
regionalization

shape analysis
districting
shape index
automated zoning procedure
pattern recognition
geographic information science
vector data modelling
raster data modelling


Shrinkage estimation in system regression model This article considers the problem of point/set estimation in a specific seemingly unrelated regression model, namely system regression model. Feasible type of shrinkage estimator and its positive part are defined for the effective regression coefficient vector, when the covariance matrix of the error term is assumed to be unknown. Their asymptotic distributional properties are evaluated. Further, related improved confidence set problems are discussed. A simulation study is conducted to evaluate the performance of the estimators.

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

seemingly unrelated regression model
shrinkage estimator

feasible estimator
positive-rule stein-type estimator
preliminary test estimator


Performance analysis of contention access period of IEEE 802.15.3 MAC protocol IEEE 802.15.3 is expected to play a significant role in the Internet of Things (IoT). It is developed for high-rate communication between low-power devices in a Wireless Personal Area Network (WPAN). The standard defines Medium Access Control (MAC) and physical layer protocols that support real-time communication over an area of ten square metres. IEEE 802.15.3 MAC consists of a combination of Carrier Sense Multiple Access/Collision Avoidance (CSMA/CA) and Time Division Multiple Access (TDMA) protocols. The channel is divided into superframe structures where each superframe consists of a beacon, a Contention Access Period (CAP) and a Channel Time Allocation Period (CTAP). In this paper we analyse the performance of the CAP period using both analytical and simulation-based methods. We simulate CSMA/CA protocol in the CAP period using NS-2. The simulation results are compared with those obtained from analytical approximations in terms of different parameters including throughput and optimal CAP periods.

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


Phishwish: a simple and stateless phishing filter We define phishing as the practice of directing unsuspecting users to fraudulent websites with the intent of obtaining personal information to be used for illicit purpose by a spammer. We introduce a new anti-phishing filter, phishwish, that has a number of advantages over existing phishing filters: it does not need to be trained, as is the case with Bayesian filters, nor does it consult centralized white or blacklists to determine whether an email is suspect. Phishwish uses a set of only 11 rules to determine the veracity of an incoming email; the results can be used to quarantine the email or to alert the user. We compare the performance of phishwish to SpamAssassin, a popular open source filter, as well as the Google phishing filters accessed from the Firefox browser. Our results indicate that phishwish outperforms existing filters in identifying phishing emails, even identifying those originated by the 'rock phish' gang, and that it aids in detection of zero-day attacks that were not caught by existing filters. Copyright (C) 2008 John Wiley & Sons, Ltd.

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


Two-Stage Monte Carlo Tree Search for Connect6 Recently, Monte Carlo tree search (MCTS) has become a well-known game search method, and has been successfully applied to many games. This method performs well in solving search trees with numerous branches, such as Go, Havannah, etc. Connect6 is a game involving a search tree with numerous branches, and it is also one of the sudden-death games. This paper thus proposes a new MCTS variant related to Connect6, called two-stage MCTS. The first stage focuses on threat space search (TSS), which is designed to solve the sudden-death problem. For the double-threat TSS in Connect6, this study proposes an algorithm called iterative threat space search (ITSS) which combines normal TSS with conservative threat space search (CTSS). The second stage uses MCTS to estimate the game-theoretic value of the initial position. This stage aims at finding the most promising move. The experimental result shows that two-stage MCTS is considerably more efficient than traditional MCTS on those positions with TSS solution in Connect6. Furthermore, according to Connect6 heuristic knowledge, this paper uses relevance-zone search to accelerate identifying winning and losing moves.

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

connect6
monte carlo tree search
threat space search

board games
conservative tss
iterative tss


proximity-based ad hoc federation among smart objects and its applications This extended abstract first proposes a new formal model of autonomic proximity-based federation among physical smart objects with wireless network connectivity and services available on the Internet, and then shows some of its application frameworks. Federation here denotes the definition and execution of interoperation among physical smart objects and/or services that are accessible either through the Internet or through peer-to-peer ad hoc communication.

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

service federation
pervasive computing
ubiquitous computing