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91.
Reviews the book Neurological aspects of addiction (2008). This book is a reference book on the neurological aspects of addiction. It is an invaluable tool for students, researchers and professionals interested in the topic of drug addiction and treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
92.
93.
Perrin Francois Bertrand Olivier Pernier Jacques 《IEEE transactions on bio-medical engineering》1987,(4):283-288
Scalp current density (SCD) makes possible the identification of scalp sources and sinks of current. SCD is reference independent and its peaks and troughs are sharper than those of the scalp potential (SP). SCD, by comparison to SP, reflects mainly the activity of cortical generators. SCD mapping appears to be a valuable tool to spatially split smeared SP distribution due to simultaneously active generators. The SCD map may be computed from any sufficiently smooth mathematical SP map. An evaluation of the error of SCD estimation is given for a surface spline method of interpolation of SP. An example of the simultaneous use of SP and SCD in the analysis of somatosensory evoked data is given. 相似文献
94.
This work introduces a self-supervised architecture for robust classification of moving obstacles in urban environments. Our
approach presents a hierarchical scheme that relies on the stability of a subset of features given by a sensor to perform
an initial robust classification based on unsupervised techniques. The obtained results are used as labels to train a set
of supervised classifiers. The outcomes obtained with the second sensor can be used for higher level tasks such as segmentation
or to refine the within-clusters discrimination. The proposed architecture is evaluated for a particular realization based
on range and visual information which produces track-based labeling that is then employed to train supervised modules that
perform instantaneous classification. Experiments show that the system is able to achieve 95% classification accuracy and
to maintain the performance through on-line retraining when working conditions change. 相似文献
95.
We present two detailed studies concerning thedmt and the multichannelhemt for power amplifications. Each work comprises a first theoretical part where the structure is optimized by simulating the device. Technological realizations are hence performed at the laboratory. The following measurements give results very encouraging and permit to foresee the superior performance relatively to that of GaAs powermesfet. 相似文献
96.
Bertrand Leigh 《电子与电脑》2005,(3):124
系统设计者在大量的应用中,常使用经济的双倍数据速率(DDR)内存。虽然DDR在概念上一目了然,但要满足它那高于100MHz速度的时序要求,却是一项挑战。由于它们的灵活性、内置特性、高速工作、大量的闸数和低成本,当今的FPGA为设计提供了有用的基础方法。DDR内存控制器设计的三个主要问题是:数据选通(DQS)和数据(DQ)间的对齐、数据的多路合成和分解以及时脉域的转换。数据选通至数据(DQS至QD)的对齐要对齐DQS和DQ,需要一个精密的DLL来动态地校准DQS。由于DDR内存在读操作时产生相位对齐的DQS和DQ,控制器必须将DQS相对于多个… 相似文献
97.
Bertrand Matths 《European Journal of Lipid Science and Technology》1997,99(5):170-174
Different oilseeds, usable as renewable resources, are analyzed for their content of condensed tannins, glucosinolates, phytic acid and its degradation products as well as for sinapine, and the results are presented. Seeds of sunflower, flax, coriander, Euphorbia lagascae, iberic. dragon head, safflor, Camelina sativa, soy, mustard, hemp and rapeseeds are used. Apart from hemp, coriander and Euphorbia lagascae different cultivars or genotypes of each species are investigated. The variation of the results of each cultivar or genotype is shown. Tannins and phytic acid are found in different amounts in all oilseeds, whereas sinapine and glucosinolates are limited to seeds from species belonging to the plant family Brassicaceae. 相似文献
98.
Experimental characterization of the chaotic dynamics of cohesionless particles: application to a V-blender 总被引:1,自引:0,他引:1
So far, most of the investigations of the dynamics of granular material in blenders have been done in 2D tumblers due to the
current lack of accurate measurement methods for the investigation of complex 3D flows. However, recent advances in the field
of non-intrusive methods have paved the way to the characterization of the chaotic dynamics in 3D blenders. This work aims
to present such an analysis in the case of a V-blender using radioactive particle tracking (RPT). Special attention is given
to the chaotic properties of mixing by performing a time-series analysis of the position of a single tracer in motion in this
blender. An original investigation of the mixing properties is also presented. More generally, this work shows that the mixing
properties of a blender can be characterized by using tools of dynamical systems theory through a time-series analysis of
data obtained from non-intrusive measurements. 相似文献
99.
Francis Gohin Bertrand Saulquin Héléne Oger-Jeanneret Loic Lozac'h Luis Lampert Alain Lefebvre Philippe Riou Franck Bruchon 《Remote sensing of environment》2008,112(8):3329-3340
The application of the new Water Framework Directive (WFD) of the European Union will require a dense and frequent monitoring of chlorophyll-a near the coast. Not counting the transitional water bodies located in the vicinity of estuaries, not less than seventy four coastal water bodies have to be monitored along the coast of the French Atlantic continental shelf and the English Channel. All the available data have to be gathered to implement a comprehensive monitoring scheme. To this purpose, we evaluate the capacity of ocean colour imagery to complete the conventional in situ data set collected in coastal networks. Satellite-derived chlorophyll-a concentration is obtained by the application of a coastal Look-Up-Table to water-leaving radiance of the Sea-viewing Wide Field Instrument Sensor (SeaWiFS) for the 1998–2004 period. Seven years of satellite-derived and in situ chlorophyll-a concentrations are compared at seven representative stations of different water bodies. These comparisons show that the satellite products are reliable in most of the situations studied and throughout the seasons. Then the satellite imagery is used to classify the coastal waters following the eutrophication risk criterion of the WFD. This classification is made according to the percentile-90 of chlorophyll-a calculated during the productive season, from March to October. Despite a lack of sensor coverage over a small fraction of the near shore waters, this work shows that the satellite monitoring can considerably ease the application of the WFD. 相似文献
100.
H. El Brouji O. Briat J.-M. Vinassa N. Bertrand E. Woirgard 《Microelectronics Reliability》2008,48(8-9):1473-1478
This paper deals with the performances fading of ultracapacitors under calendar life and power cycling tests. The used impedance model is analytical and based on physical quantities as double layer capacitance, specific area and electrolyte conductivity but also on elementary electrodes dispersion. This model is validated in frequency domain using the initial state of the tested ultracapacitor. Then, the two types of tests are presented and specified. A periodic characterization based on impedance spectroscopy is done in order to quantify the impedance changes during ageing tests. The obtained results confirm that impedance real part is increasing and the capacitance is decreasing during the two ageing tests, nevertheless the way they change is different. Indeed the impedance real part increase is independent of the frequency in calendar life test while, in power cycling test, this increase is accentuated at low frequencies. This difference will be explained thanks to impedance model parameters evolution. This study confirms that the two ageing tests affect differently the ultracapacitor performances. 相似文献