Genetic programming for multibiometrics

Biometric systems suffer from some drawbacks: a biometric system can provide in general good performances except with some individuals as its performance depends highly on the quality of the capture… One solution to solve some of these problems is to use multibiometrics where different biometric systems are combined together (multiple captures of the same biometric modality, multiple feature extraction algorithms, multiple biometric modalities…). In this paper, we are interested in score level fusion functions application (i.e., we use a multibiometric authentication scheme which accept or deny the claimant for using an application). In the state of the art, the weighted sum of scores (which is a linear classifier) and the use of an SVM (which is a non linear classifier) provided by different biometric systems provide one of the best performances. We present a new method based on the use of genetic programming giving similar or better performances (depending on the complexity of the database). We derive a score fusion function by assembling some classical primitives functions (+, ∗, −, … ). We have validated the proposed method on three significant biometric benchmark datasets from the state of the art.     

A circular inclusion in a finite domain II. The Neumann-Eshelby problem

Summary This is the second paper in a series concerned with the precise characterization of the elastic fields due to inclusions embedded in a finite elastic medium. In this part, an exact and closed form solution is obtained for the elastic fields of a circular inclusion embedded in a finite circular representative volume element (RVE), which is subjected to the traction (Neumann) boundary condition. The disturbance strain field due to the presence of an inclusion is related to the uniform eigenstrain field inside the inclusion by the so-called Neumann-Eshelby tensor. Remarkably, an elementary, closed form expression for the Neumann-Eshelby tensor of a circular RVE is obtained in terms of the volume fraction of the inclusion. The newly derived Neumann-Eshelby tensor is complementary to the Dirichlet-Eshelby tensor obtained in the first part of this work. Applications of the Neumann-Eshelby tensor are discussed briefly.     

Monitoring of slow ground deformation by ERS radar interferometry on the Vauvert salt mine (France): Comparison with ground-based measurement

The differential SAR Interferometry (DInSAR) technique has been applied to a test site near Vauvert (France) to detect and monitor ground deformation. This site corresponds to the location of an industrial exploitation of underground salt using the solution mining technique. An area of subsidence has been observed using in situ measurements. Despite conditions unfavorable for InSAR because of the vegetal cover, we show that radar remote sensing observations provide valuable information which substantially improves our knowledge of the phenomenon. An adaptive phase filtering process has been used to improve the coherence level. In particular, our study shows that the geometry of the subsidence bowl is different to that previously assumed using ground-based techniques only. The size of the subsidence bowl (8 km) is larger than expected. This information will be useful for further modeling of the deformation and to improve the coverage of the in situ measurement networks. It also shows that radar interferometry can be used for the long-term monitoring of such sites and to predict potential environmental issues.     

Experience with a Hybrid Processor: K-Means Clustering

We discuss hardware/software co-processing on a hybrid processor for a compute- and data-intensive multispectral imaging algorithm, k-means clustering. The experiments are performed on two models of the Altera Excalibur board, the first using the soft IP core 32-bit NIOS 1.1 RISC processor, and the second with the hard IP core ARM processor. In our experiments, we compare performance of the sequential k-means algorithm with three different accelerated versions. We consider granularity and synchronization issues when mapping an algorithm to a hybrid processor. Our results show that speedup of 11.8X is achieved by migrating computation to the Excalibur ARM hardware/software as compared to software only on a Gigahertz Pentium III. Speedup on the Excalibur NIOS is limited by the communication cost of transferring data from external memory through the processor to the customized circuits. This limitation is overcome on the Excalibur ARM, in which dual-port memories, accessible to both the processor and configurable logic, have the biggest performance impact of all the techniques studied.     

Trying to adopt systems development methodologies — a case-based exploration of business users' interests

Information systems methodologies are an important component of the IS infrastructure and a primary device for organizing systems development work. Evidence suggests that methodology adoption and use are problematic. This research seeks to generate insight into business users' interest in adoption through detailed examination of a case. A framework is developed for organizing relevant research findings. The field research methods are described and details of the case reported. The case highlights the role of business managers in methodology adoption and the influence of business pressures originating in the strategic environment. Analysis shows the organizing framework to require extension to include a more direct role for business decision makers. it is argued that previous research has obscured the legitimate concern of business with systems development methodologies. As business increasingly asserts its interest in and control over IS, it will be necessary to give greater consideration to the needs of business in the selection and adoption of methodologies.     

Lead Extraction from Contaminated Soil Using Water-Soluble Polymers

The applicability of water-soluble polymers as extractants for the remediation of heavy metal-contaminated soils has been explored using a lead-contaminated Superfund soil as a sample system. Polyethylenimine (PEI) was functionalized with bromo- or chloroacetic acid to give an aminocarboxylate chelating group, which effectively binds lead. The resulting polymer, PEIC, has extraction properties similar to the molecular chelator ethylenediaminetetraacetic acid. A series of studies was done to probe optimum conditions for lead extraction from soils obtained from the Cal-West Superfund site in New Mexico that contained approximately 10,000 ppm of Pb. In batch extraction experiments using polymer functionalized at two different levels, the polymers removed greater than 97% of the lead from the soils. Subsequent experiments demonstrated that the selective extraction of lead could be controlled by varying polymer functionalization levels. Concentration and regeneration of the polymers using ultrafiltration was also demonstrated. Release of lead from the polymer was accomplished by acidification to pH 1 with HCl. Subsequent ultrafiltration allowed recovery of the extractant polymer for reuse.     

Pregnenolone-binding proteins in the rat adrenal cortex

Rat adrenal cortex contains a protein(s) that binds pregnenolone with high affinity. This binding, demonstrated by gel filtration and by a dextran-coated charcoal method, was associated with the cytosol and with fractions solubilized by sonication from the mitochondria and microsomes. The binding of pregnenolone was saturable and was inhibited by mercurials and proteolytic enzymes. Pregnenolone-binding was not influenced by the presence of progesterone, deoxycorticosterone, corticosterone or aldosterone, but was inhibited by steroids with a 3beta-hydroxy-5-ene structure similar to pregnenolone, and by hydroxymethylene steroid and cyanoketone. We suggest that this protein is involved in the intracellular transport and retention of pregnenolone within adrenal cortical cells.     

Uncertainty Management in the Unit Commitment Problem

Uncertainty in power systems operations has been traditionally managed by multistage decision making and operating reserve requirements. A familiar example of multistage decisions is day-ahead unit commitment and real-time economic dispatch. An alternate approach for managing uncertainty is a stochastic formulation, which allows the explicit modeling of the sources of uncertainty. This paper compares stochastic and reserve methods and evaluates the benefits of a combined approach for the efficient management of uncertainty in the unit commitment problem. Numerical studies show that unit commitment solutions obtained for the combined approach are robust and superior with respect to the traditional approach in terms of both economics and reliability metrics.     

三相异步电机新模型及其仿真与实验

介绍了三相异步电机的一个新模型。新模型由原始的相轴线模型经过变换得到。该模型可应用在电机定子三相参数不对称的状态。计算机仿真和电机模拟实验表明：在派克方程适用范围，新模型与PARK模型的响应完全一致：当电机定子三相参数不对称时，此时已超出PARK模型的适用范围，新模型的仿真计算结果与电机的实验数据相当吻合。新模型具有比PARK模型更广的适用范围。该模型在三相异步电机的监测及控制方面有广泛的应用前景。