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A brain–computer interface (BCI) is a system which provides direct communication between the mind of a person and the outside world by using only brain activity (EEG). The event-related potential (ERP)-based BCI problem consists of a binary pattern recognition. Linear discriminant analysis (LDA) is widely used to solve this type of classification problems, but it fails when the number of features is large relative to the number of observations. In this work we propose a penalized version of the sparse discriminant analysis (SDA), called generalized sparse discriminant analysis (GSDA), for binary classification. This method inherits both the discriminative feature selection and classification properties of SDA and it also improves SDA performance through the addition of Kullback–Leibler class discrepancy information. The GSDA method is designed to automatically select the optimal regularization parameters. Numerical experiments with two real ERP-EEG datasets show that, on one hand, GSDA outperforms standard SDA in the sense of classification performance, sparsity and required computing time, and, on the other hand, it also yields better overall performances, compared to well-known ERP classification algorithms, for single-trial ERP classification when insufficient training samples are available. Hence, GSDA constitute a potential useful method for reducing the calibration times in ERP-based BCI systems. [ABSTRACT FROM AUTHOR]

A Wireless Sensor Networks (WSN) usually consists of numerous wireless devices deployed in a region of interest, each able to collect and process environmental information and communicate with neighboring devices. It can thus be regarded as a Multi-Agent System for territorial security, where individual agents cooperate with each other to avoid duplication of effort and to exploit other agent’s capacities. The problem of sensor deployment becomes non-trivial when we consider environmental factors, such as terrain elevations. Due to the fact that all sensors are homogeneous, the chromosomes that encode sensor positions are actually interchangeable, and conventional crossover schemes such as uniform crossover would cause some redundancy as well as over-concentration in certain specific geographical area. We propose a Parsing Crossover Scheme that intends to reduce redundancy and ease geographical concentration pattern in an effort to facilitate the search. The proposed parsing crossover method demonstrates better performances than those of uniform crossover under different terrain irregularities. [ABSTRACT FROM AUTHOR]

The effect of a fracture on seismic wave propagation can be represented in terms of the normal and shear fracture compliance. In many studies, fractures are assumed to have no preferential orientation for slip along the fracture plane. However, examination of fractures found in recovered cores or in exposed outcrops shows irregularities, such as hackles or slickensides, which are formed in the direction of joint/fault propagation. These irregularities, represented as sawtooth ridges, can be expected to facilitate movement in a particular direction more than the opposite direction, in a way that depends on the height and shape of the irregularities. As a result, fractured rocks should exhibit a different compliance for shear in one direction compared with shear in the opposite orientation. We used numerical modeling to offer a critical assessment of this phenomenon by directly calculating the change in normal and shear compliance in the presence of hackles. The effect of the geometry of the hackles, the friction coefficient between fracture surfaces, and the role of normal stresses on the ratio of normal-to-shear fracture compliance were evaluated. [ABSTRACT FROM AUTHOR]

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Abstract: In 2009, Janson [Poset limits and exchangeable random posets, Institut Mittag-Leffler preprint, 36pp, arXiv:0902.0306] extended the recent theory of graph limits to posets, defining convergence for poset sequences and proving that every such sequence has a limit object. In this paper, we focus on k-dimensional poset sequences. This restriction leads to shorter proofs and to a more intuitive limit object. As before, the limit object can be used as a model for random posets, which generalizes the well known random k-dimensional poset model. This investigation also leads to a definition of quasirandomness for k-dimensional posets, which can be captured by a natural distance that measures the discrepancy of a k-dimensional poset. [Copyright &y& Elsevier]

The objective of this study is to develop a computational model that accurately describes the dynamic behavior of a non-Newtonian power-law film formed after a drop impinges on a flat surface. The non-Newtonian drop deposition and spreading process is described by a model based on one developed for Newtonian liquids. The effects of variations in non-Newtonian liquid rheological parameters, such as Ren (the non-Newtonian Reynolds number), n (the flow behavior index), and We (the Weber number), are studied in detail. Results show that a reduction in the viscous forces results in enhanced spreading of the film followed by a more rapid recession. An increase in surface tension results in reduced spreading of the film, followed by a more rapid recession. Model predictions of film diameter as a function of time were larger than corresponding experimental values obtained as part of this study However the discrepancy never exceeded 21%, demonstrating that the model accurately predicts the phenomena of interest. This comparison also shows that the results are in best agreement for large non-Newtonian Reynolds numbers and small non-Newtonian Ohnesorge numbers (√We/Ren). [ABSTRACT FROM AUTHOR]

Abstract: This paper addresses the jobshop and the flowshop scheduling problems with minimum and maximum time lags. To solve this kind of problems, we propose adaptations of Climbing Discrepancy Search (CDS). We study various parameter settings. Computational experiments are provided to evaluate the propositions. [ABSTRACT FROM AUTHOR]

Abstract: In the past decade, significant progress has been achieved in developing generic primal heuristics that made their way into commercial mixed integer programming (MIP) solver. Extensions to the context of a column generation solution approach are not straightforward. The Dantzig-Wolfe decomposition principle can indeed be exploited in greedy, local search, rounding or truncated exact methods. The price coordination mechanism can bring a global view that may be lacking in some “myopic” approaches based on a compact formulation. However, the dynamic generation of variables requires specific adaptation of heuristic paradigms. The column generation literature reports many application specific studies where primal heuristics are a key to success. There remains to extract generic methods that could be seen as black-box primal heuristics for use across applications. In this paper we review generic classes of column generation based primal heuristics. We then focus on a so-called “diving” method in which we introduce diversification based on Limited Discrepancy Search. While being a general purpose approach, the implementation of our heuristic illustrates the technicalities specific to column generation. The method is numerically tested on variants of the cutting stock and vehicle routing problems. [ABSTRACT FROM AUTHOR]

Keeping existing vector databases up to date is a real challenge for GIS data providers. This study directly compares a map with a more recent image in order to detect the discrepancies between them. An automatic workflow was designed to process the image based on existing information extracted from the vector database. First, geographic object-based image analysis provided automatically labeled image segments after matching the vector database to the image. Then, discrepancies were detected using a statistical iterative trimming, where outliers were excluded based on a likelihood threshold. Applied on forest map updating, the proposed workflow was able to detect about 75 percent of the forest regeneration, and 100 percent of the clear cuts with less than 10 percent of commission errors. This discrepancy detection approach assumes that discrepancy corresponds to small proportion of the map area and is very promising in diverse applications thanks to its flexibility. [ABSTRACT FROM AUTHOR]

Interpreting China's military expenditure has been a complicated issue with important regional implications. This article will first look at the various estimates of China's military budget and the discrepancies in the numbers as well as the geopolitical rationale driving Chinese military planning. Although China publishes its official defense budget and provides justifications for increases in its military spending, most observers remain skeptical of the accuracy of the official figures and wary of the military modernization efforts. This skepticism has shaped the responses of other Asia-Pacific nations toward China's military modernization. Ultimately, even if the Chinese leadership views the military buildup as a natural part of the country's ascension to great power status, the uncertainties surrounding its military expenditures actually undermine the contention that China's rise will be peaceful. [ABSTRACT FROM AUTHOR]

In the history of surveying and mapping, a large volumes of topographic maps and digital elevation models have been created at various scales throughout the world. However, positional errors and geometric distortions may exist in the topographic contour maps and their derived DEMs due to inaccurate ground control and poor navigation techniques in the early years. In this paper, we present a new technique to detect and correct positional errors and geometric distortions in topographic data based on rigorous Synthetic Aperture Radar (SAR) image simulation and mathematical modeling of SAR imaging geometry. Our method has been successfully applied to two USGS topographical data sets in Antarctica. Using Radarsat SAR imagery, positional errors of these two data sets have been reduced from 5 km to 200 m and from 200 m to 50 m, respectively. [ABSTRACT FROM AUTHOR]

A stochastic model for the generation of observed income distributions is used to provide an explanation for the Pareto law of incomes. The basic assumptions of the model are that the evolution of individual incomes follows Gibrat's law and that the population or workforce is growing at a fixed (probabilistic) rate. Analysis of the model suggests that Paretian behavior can occur in either or both tails of an income distribution. It is shown that the magnitude of the upper-tail Pareto exponent depends on the interaction between the distribution of the growth in incomes and the growth in the size of the earning population. In particular a small Pareto exponent can be expected to occur for a population exhibiting fast or highly variable growth in incomes coupled with relatively slow population growth. [ABSTRACT FROM AUTHOR]

This paper presents a general mathematical treatment of serial manipulators, an important example of which is the servo head. The paper includes validation by application to the angle head via comparison with the previously known transformations and a new application to the error analysis of the angle head. The usual approach to the error analysis of a servo head is to develop a geometrical model by elementary geometrical considerations using trigonometric relationships and various simplifying assumptions. This approach is very error prone, difficult to verify and extremely time consuming. The techniques described here constitute matrix methods that have been programmed in a general way to derive automatically the analytical equations relating the angles of rotation of the head and alignment errors in the head to the position of the tool and errors in that position. The approach is to use rotation and transformation matrices to evaluate the influence of the various errors such as offsets and angular errors. A general approach to the sign convention and notation for angular errors is presented in an attempt to reduce the possibility of errors of definition. [ABSTRACT FROM AUTHOR]

The article offers information on the results of the online survey of science technicians working in British schools and universities conducted by the Association for Science Education (ASE) in 2010. It says that 43% of technicians belong to age bracket between 51 and 60. It mentions the big discrepancy between the qualifications required by employers and the qualifications of the employees. More so, technicians in 2010 were found to be better qualified than technicians in 2000.