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Neutron-gamma discrimination method based on blind source separation and machine learning

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Nuclear Science and Techniques 2021年第2期32卷 70-80页

作者： Hanan Arahmane El-Mehdi Hamzaoui yann Ben Maissa Rajaa Cherkaoui El Moursli Universite´Paris-Saclay CEAList91120 PalaiseauFrance Equipe des Sciences de la Matie`re et du Rayonnement(ESMaR) Faculty of SciencesMohammed V University in RabatB.P.1014 RPRabatMorocco National Centre for Nuclear Energy Science and Technology(CNESTEN)B.P.1382 R.P.10001RabatMorocco Laboratory of Telecommunications Networks and Service SystemsNational Institute of Posts and TelecommunicationsAllal El Fassi AvenueRabatMorocco

The discrimination of neutrons from gamma rays in a mixed radiation field is crucial in neutron detection *** approaches have been proposed to enhance the performance and accuracy of neutron-gamma ***,their performances are often associated with certain factors,such as experimental requirements and resulting mixed *** main purpose of this study is to achieve fast and accurate neutron-gamma discrimination without a priori information on the signal to be analyzed,as well as the experimental ***,a novel method is proposed based on two *** first method exploits the power of nonnegative tensor factorization(NTF)as a blind source separation method to extract the original components from the mixture signals recorded at the output of the stilbene scintillator *** second one is based on the principles of support vector machine(SVM)to identify and discriminate these *** addition to these two main methods,we adopted the Mexican-hat function as a continuous wavelet transform to characterize the components extracted using the NTF *** resulting scalograms are processed as colored images,which are segmented into two distinct classes using the Otsu thresholding method to extract the features of interest of the neutrons and gamma-ray components from the background *** subsequently used principal component analysis to select the most significant of these features wich are used in the training and testing datasets for ***-variance analysis is used to optimize the SVM model by finding the optimal level of model complexity with the highest possible generalization *** this framework,the obtained results have verified a suitable bias–variance trade-off *** achieved an operational SVM prediction model for neutron-gamma classification with a high true-positive *** accuracy and performance of the SVM based on the NTF was evaluated and validated by comparing it to the charge comparison

关键词： Blind source separation Nonnegative tensor factorization(NTF) Support vector machines(SVM) Continuous wavelets transform(CWT) Otsu thresholding method

基于谱元-简正振型耦合方法的核幔边界D″区地震波波形模拟方法研究

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地球物理学报 2013年第4期56卷 1216-1225页

作者：赵明赵亮 yann Capdeville 中国科学院地质与地球物理研究所岩石圈演化国家重点实验室北京100029 中国科学院大学北京100049 Laboratoire de planftologie et de geodynamique de Nantes CNRS France

本文拓展了一种模拟地震波在地球核幔边界D″区各向异性介质中传播的数值方法:谱元-简正振型耦合方法(CSEM).该方法通过在球对称各向同性介质空间采用简正振型方法,在各向异性的D″区采用谱元方法,并在两种介质的边界采用"DtN"算子耦合... 详细信息

本文拓展了一种模拟地震波在地球核幔边界D″区各向异性介质中传播的数值方法:谱元-简正振型耦合方法(CSEM).该方法通过在球对称各向同性介质空间采用简正振型方法,在各向异性的D″区采用谱元方法,并在两种介质的边界采用"DtN"算子耦合的策略计算一维模型PREM(见文献[1])或修改后的D″区横向各向同性VTI-PREM模型的理论地震图.模拟所得数值解结果与采用简正振型方法得到的解析解结果进行对比以验证方法的精度.在中国科学院地球深部结构重点实验室高性能计算机上使用128个CPU计算得到的结果显示,在10-5～0.125Hz的频率范围内谱元简正振型法得到的波形与简正振型方法能很好拟合.此外,对于VTI介质结构模型,谱元简正振型法能够准确模拟S波分裂现象,从而验证了谱元简正振型耦合方法对各向异性介质中地震波传播数值模拟是一种有效的方法.

关键词：谱元-简正振型方法简正振型法合成理论地震图横向各向同性

On the Hydrostatic and Darcy Limits of the Convective Navier-Stokes Equations

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Chinese Annals of Mathematics,Series B 2009年第6期30卷 683-696页

作者： yann BRENIER U.M.R.CNRS 6621 Universit de Nice (FR 2800 W.Dblin)Institut Universitaire de FranceParc Valrose06108 Nice Cedex 02France

The author studies two singular limits of the convective Navier-Stokes *** hydrostatic limit is first studied:the author shows the existence of global solutions with a convex pressure field and derives them from the convective Navier-Stokes equations as long as the pressure field is smooth and strongly *** (friction dominated) Darcy limit is also considered,and a relaxed version is studied.

关键词： Atmospheric sciences Fluid mechanics Asymptotic analysis

Impact of the blockage ratio on the transport of sediment in the presence of a hydrokinetic turbine: Numerical modeling of the interaction sediment and turbine

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International Journal of Sediment Research 2021年第6期36卷 696-710页

作者： Fatima Khaled Sylvain Guillou yann Méar Ferhat Hadri University of Caen Normandy LISV University of Versailles Conservatoire National des Arts et Métiers University of Caen Normandy

Interactions between hydrokinetic turbines and near scale and far scale bed sediment particles are considered a critical area of assessment; however, a limited number of research studies have been published to address this issue. The current paper explores the influence of the blockage ratio on the morphology evolution downstream from a hydrokinetic turbine. A modeling framework is derived to predict the significant transport induced by a turbine installed on the erodible fluvial sandy bed surface,such as the Eulerian multi-phase model for the sediment and the Blade Element Momentum Theory(BEMT) for the turbine, using the open source platform OpenFOAM. Two configurations of different blockage ratios are considered. The configurations show differences in the bed morphology and the sediment transport. It has been shown for both configurations that the scour capabilities are enhanced below the turbine due to the acceleration of the flow and increasing local shear stress on the sediment.

关键词： Environmental impact Blockage effects Euler-Euler multiphase Hydrokinetic turbine Numerical simulations OpenFOAM

Comparison of Ashes Produced in a Biomass Moving Grate Boiler by Wood Chips and Sewage Sludge

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Fluid Dynamics & Materials Processing 2022年第5期18卷 1419-1425页

作者： Baraket Nada Brandelet Benoit TrouvéGwenaëlle Rogaume yann Universitéde Lorraine-LERMAB-ERBE Epinal88000France LGRE Institut de Recherche Jean-Baptiste Donnet Universitéde Haute-AlsaceMulhouse6809France ADEME Angers49004France

One option to fight global warming is to convert our use of fossil energy into renewables such as biomass ***,the forest preservation and the quality of the ambient air are also two major ***,the use of biomass waste without any supplementary emissions could represent a part of the *** this study,two fuels were considered for a 200 kW moving grate boiler.A multicyclone and a bag filter were fitted on the *** first fuel consisted of classical wood chips whereas the second was a mixture of wood chips with sewage *** second fuel presented a high ashes mass ratio compared to wood *** aim was to verify the possibility to burn this kind of fuel without any modification of the *** first relevant result is that the conventional pollutants,i.e.,CO and NOx,remained under the emissions limits even with the sewage sludge *** Total Suspended Particles emissions at the exhaust were always under 5.4 mg·Nm-3 dry based corrected at 6%of O_(2),which is low with respect to the standard *** majority of the ashes remained on the combustion ***,with both fuels,about 5%of ashes mass remained in the heat ***,the heat exchanger was more clogged with the second fuel,which produced five time more *** may lead to a yield ***,sewage sludge can be used in a wood boiler without any issue if an automatic exchanger sweep is fitted on the installation.

关键词： Combustion energy biomass ashes TSP

Targeting transcriptional regulators for treatment of anaplastic thyroid cancer

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Journal of Cancer Metastasis and Treatment 2021年第1期7卷 381-398页

作者： Woo Kyung Lee Sheue-yann Cheng Laboratory of Molecular Biology Center for Cancer ResearchNational Cancer InstituteNational Institutes of HealthBethesdaMD 20892USA

Dysregulation of genes perpetuates cancer *** carcinogenesis,cancer cells acquire dependency of aberrant transcriptional programs(known as“transcription addiction”)to meet the high demands for uncontrolled *** needs for particular transcription programs for cancer growth could be *** dependencies of certain transcription regulators could be exploited for therapeutic *** thyroid cancer(ATC)is an extremely aggressive human cancer for which new treatment modalities are urgently *** resistance to conventional treatments and the lack of therapeutic options for improving survival might have been attributed to extensive genetic heterogeneity due to subsequent evolving genetic alterations and clonal selections during *** this genetic complexity,mounting evidence has revealed a characteristic transcriptional addiction of ATC cells resulting in evolving diverse oncogenic signaling for cancer cell *** transcriptional addiction has presented a huge challenge for effective targeting as shown by the failure of previous targeted ***,an emerging notion is that many different oncogenic signaling pathways activated by multiple upstream driver mutations might ultimately converge on the transcriptional responses,which would provide an opportunity to target transcriptional regulators for treatment of ***,we review the current understanding of how genetic alterations in cancer distorted the transcription program,leading to acquisition of transcriptional *** also highlight recent findings from studies aiming to exploit the opportunity for targeting transcription regulators as potential therapeutics for ATC.

关键词： Transcriptional addiction transcription oncogene addiction cancer stem cell thyroid hormone receptors steroid receptor coactivators BET inhibitor anaplastic thyroid cancer

Changes in reproductive investment with altitude in an alpine plant

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Journal of Plant Ecology 2009年第3期2卷 125-134页

作者： yann Hautier Christophe F.Randin Jurg Stocklin Antoine Guisan Department of Ecology and Evolution University of LausanneBaˆtiment BiophoreCH-1015 LausanneSwitzerland Institute of Botany University of BaselSchoenbeinstrasse 6CH-4056 BaselSwitzerland Present address:Institute of environmental Sciences University of ZurichWinterthurerstrasse 190CH-8057 ZurichSwitzerland

Aims In perennial species,the allocation of resources to reproduction results in a reduction of allocation to vegetative growth and,therefore,impacts future reproductive *** a consequence,variation in this trade-off is among the most important driving forces in the life-history evolution of perennial plants and can lead to locally adapted *** addition to genetic variation,phenotypic plasticity might also contribute to local adaptation of plants to local conditions by mediating changes in reproductive *** on the importance of genetic and environmental effects on the tradeoff between reproduction and vegetative growth is therefore essential to understand how plants may respond to environmental *** We conducted a transplant experiment along an altitudinal gradient from 425to1921 min the frontrange of the Western Alps of Switzerland to assess the influence of both altitudinal origin of populations and altitude of growing site on growth,reproductive investment and local adaptation in Poa *** findings In our study,the investment in reproduction increased with plant *** growth and the relative importance of reproductive investment decreased in populations originating from higher altitudes compared to populations originating from lower *** changes in reproductive investment were mainly explained by differences in plant *** contrast to genetic effects,phenotypic plasticity of all traits measured was low and not related to *** a result,the population from the lowest altitude of origin performed best at all *** results indicate that in *** genetic differences in growth and reproductive investment are related to local conditions affecting growth,*** competition and soil moisture content.

关键词： Poa alpina transplantation altitudinal gradient genetic diversity phenotypic plasticity

FACTORS OF 3GWC SYSTEMS FOR DRAWING UP CUSTOMIZED STRATEGIES OF PROMOTION

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作者： yann Martel.

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Journal of Systems Science and Systems Engineering 2011年第3期20卷 365-381页

作者： Hsin-Pin FU Hwan-yann SU Fang-Hua WANG Ching-Yi CHANG Hung-Hsuan LEE Department of Marketing and Distribution Management National Kaohsiung First University of Science and Technology Kaohsiung Taiwan China Department of Asia-Pacific Industrial and Business Management National University of Kaohsiung Taiwan China Antai College of Economics ＆ Management Shanghai Jiao Tong University Shanghai China Antai College of Economics ＆ Management Shanghai Jiao Tong University Shanghai China Institute of Management National Kaohsiung First University of Science and Technology Taiwan China

This study utilizes fuzzy analytic hierarchy process （FAHP） to analyze decision-making pattems with regard to third-generation wireless communications （3GWC） service adoption, and to provide customized strategic recommendations to suppliers of 3GWC services regarding marketing and resource allocation in the context of the Chinese 3GWC market. First of all, a three-layer hierarchy of 3GWC adoption factors is developed by referring to the relevant literature and industry reports. A questionnaire of pairwise comparisons in the fuzzy AHP format is then designed and distributed to experts familiar with the handset market in Shanghai, China. These surveys are then analyzed using fuzzy AHP to establish an understanding of the weights and impacts of the various factors. The results show that the four most important factors for the adoption of 3GWC systems are：（i） handset price and voice and data-transmission fees; （ii） handset aesthetics; （iii） personalization; and （iv） network coverage. These findings suggest that providers of such services should customize and diversify the content/applications they offer and ensure the speed and reliability of network access. In addition, handset designs should be in accordance with consumer demands. If these steps can be achieved, then consumers will adopt 3GWC services more rapidly.

关键词： 3GWC (third generation mobile) adoption factors FAHP