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The onset in spring and the end in autumn of the thermal and vegetative growing season affect calving time and reproductive success in reindeer

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Current Zoology 2020年第2期66卷 123-134页

作者： Amelie Paoli Robert B.Weladji Фystein Holand Jouko Kumpula Department of Biology Concordia University7141 Sherbrooke Street WestMontrealQCH4B 1R6Canada Department of Animal and Aquacultural Sciences Norwegian University of Life SciencesAsPO Box 5003Norway Natural Resources Institute of Finland(Luke) Reindeer Research Station99910Finland

A developing trophic mismatch between the peak of energy demands by reproducing animals and the peak of forage availability has caused many species'reproductive success to *** match-mismatch hypothesis(MMH)is an appealing concept that can be used to assess such fitness ***,concerns have been raised on applying the MMH on capital breeders such as reindeer because the reliance on maternal capita rather than dietary income may mitigate negative effects of changing *** a long-term dataset of reindeer calving dates recorded since 1970 in a semidomesticated reindeer population in Finnish Lapland and proxies of plant phenology;we tested the main hypothesis that the time lag between calving date and the plant phenology in autumn when females store nutrient reserves to finance reproduction would lead to consequences on reproductive success,as the time lag with spring conditions *** predicted,the reproductive success of females of the Kutuharju reindeer population was affected by both the onset of spring green-up and vegetative senescence in autumn as calves were born heavier and with a higher first-summer survival when the onset of the vegetation growth was earlier and the end of the thermal growing season the previous year was earlier as *** results demonstrated that longer plant growing seasons might be detrimental to reindeer's reproductive success if a later end is accompanied by a reduced abundance of mushrooms.

关键词： lagged effect match-mismatch hypothesis plant phenology Rangiter tarandus time lag ungulates

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手写体数字有效鉴别特征的抽取与识别

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计算机研究与发展 1999年第12期36卷 1484-1489页

作者：金忠胡钟山杨静宇刘克孙靖夷南京理工大学计算机科学系南京210014 concordia大学模式识别与机器智能中心

文中提出了基于后验概率估计的多特征多分类器组合识别的估计法，并提出了基于具有统计不相关性的最佳鉴别变换与ＫＬ变换抽取手写体数字的有效鉴别特征的方法．实验采用ＣｏｎｃｏｒｄｉａＵｎｉｖｅｒｓｉｔｙＣＥＮＰＡＲＭＩ手写... 详细信息

文中提出了基于后验概率估计的多特征多分类器组合识别的估计法，并提出了基于具有统计不相关性的最佳鉴别变换与ＫＬ变换抽取手写体数字的有效鉴别特征的方法．实验采用ＣｏｎｃｏｒｄｉａＵｎｉｖｅｒｓｉｔｙＣＥＮＰＡＲＭＩ手写体数字数据库．用最近邻距离分类器与最近邻相关分类器这两个分类器，对手写体数字的１２个特征做多特征多分类器组合识别实验．实验结果表明：估计法优于常用的投票法与计分法，估计法的识别率高达９７％．本文最后基于一个严格的结构分类器与估计法提出了一个集成分类器，该集成分类器获得了更好的实验结果：识别率、拒识率与可靠性分别可达到９７．１５％、２．０５％、９９．１８％，这是目前在该手写体数字数据库上所得到的最好的实验结果．

关键词：计算机手写体数字识别特征抽取模式识别

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A MODEL OF PARALLEL INTERACTIVE PROCESSING

A MODEL OF PARALLEL INTERACTIVE PROCESSING

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计算机，通信，控制与电力工程国际会议

作者： Tao Li Yuan Yan Tang Department of Computer Science Concordia University 1455 de Maisonneuve Blvd.W.MontrealCANADA

A model of interactive programs is proposed in this paper along with algorithms for program and data mapping onto parallel *** propose that parallel processing of interactive programs be based on interface systems. Al... 详细信息

ISBN: (纸本)0780312333

关键词： A MODEL OF PARALLEL INTERACTIVE PROCESSING

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基于轮廓分段特征的手写体阿拉伯数字识别

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计算机学报 1999年第10期22卷 1065-1073页

作者：娄震胡钟山杨静宇刘克孙靖夷南京理工大学计算机科学系南京210094 concordia大学模式识别及机器智能研究中心

文中提出了一种新的手写体数字识别的结构方法，将字符轮廓划分为特征片段：凸弧、凹弧、直线段、端点、洞，并由特征片段得到特征基元，构成对字符结构的完整描述．文中还提出了一种轮廓点的曲率滤波方法以及利用字符的特征基元序列测... 详细信息

文中提出了一种新的手写体数字识别的结构方法，将字符轮廓划分为特征片段：凸弧、凹弧、直线段、端点、洞，并由特征片段得到特征基元，构成对字符结构的完整描述．文中还提出了一种轮廓点的曲率滤波方法以及利用字符的特征基元序列测量两样本之间的相似度方法．在此基础上，提出了一个两阶段的识别方法及两种拒识准则．在第一阶段，通过基于相似度比较的分类器，对每个待识字符识别或拒识．拒识的字符进入第二阶段识别．拒识分两种情况：待识字符与任一类训练样本都不相似，称为第一类拒识；与两类训练样本都相似，为第二类拒识．在第二阶段，对于第一类拒识，重新提取特征后再入分类器．对于第二类拒识，用一个专用的二义识别过程识别．

关键词：手写体数字识别特征提取轮廓跟踪拒识准则

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Simulating the Seismic Response of Concentrically Braced Frames Using Physical Theory Brace Models

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Open Journal of Civil Engineering 2013年第2期3卷 69-81页

作者： Liang Chen Lucia Tirca Department of Building Civil and Environmental Engineering Concordia University Montreal Canada Department of Civil Geological and Mining Engineering Ecole Polytechnique Montreal Canada

The aim of this paper is to assess the accuracy of brace models formulated in Drain 2DX and OpenSees by comparing the simulated results with those obtained from experimental tests. Both, Drain 2DX and OpenSees rely on the physical theory brace model. In this study, experimental tests conducted on the behaviour of structural hollow section braces subjected to symmetric and asymmetric quasi-static cyclic loading were selected for calibrating the numerical model. In addition, the predicted failure strain parameter resulted from a proposed empirical equation as a function of slenderness ratio, width-to-thickness ratio and steel properties was used to define the low-cycle fatigue material that was assigned to model braces in OpenSees. It is concluded that both Drain 2DX and OpenSees brace models give a good prediction in terms of maximum tensile and buckling force, as well as interstorey drift. However, in Drain 2DX, the brace model is not able to replicate the out-of-plan buckling and the braced frame model cannot provide an accurate response when the system experiences highly nonlinear demand. To emphasise the differences in performance between Drain 2DX and OpenSees, the behaviour of a 4-storey concentrically braced frame with zipper bracing configuration, located in Victoria, BC, was investigated.

关键词： Brace Model Plastic Hinge Hysteretic Energy Seismic Response Time-History Analysis

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线性电磁矢量阵列的空时极化平滑算法及相干源多参数估计

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电子与信息学报 2010年第12期32卷 3032-3036页

作者：刘兆霆何劲刘中南京理工大学电子工程系南京210094 concordia university电子与计算机工程系

该文提出了一种基于线性电磁矢量阵列的空时极化平滑算法(STPSA),解决了相干信源的频率,2维波达方向和极化参数的联合估计问题。该算法通过对不同子阵和矢量传感器不同传感单元的测量数据及其相应延迟数据进行平滑,实现解相干预处理并... 详细信息

该文提出了一种基于线性电磁矢量阵列的空时极化平滑算法(STPSA),解决了相干信源的频率,2维波达方向和极化参数的联合估计问题。该算法通过对不同子阵和矢量传感器不同传感单元的测量数据及其相应延迟数据进行平滑,实现解相干预处理并抑制噪声干扰,然后利用传播算子方法得到相应的参数估计。与目前的算法相比,该文提出的算法能够同时实现相干信源的多个参数联合估计;无需通过奇异值或特征值分解提取信号/噪声子空间,也无须进行参数搜索,有较低的运算量;另外,算法能够通过增加相邻阵元的间隔来扩展阵列的有效孔径,改善估计性能,且无须进行参数去模糊处理。仿真结果验证了算法的有效性。

关键词：阵列信号处理波达方向估计相干信号极化

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Face Recognition Based on Maximum Sparse Coefficients of Object Region

Face Recognition Based on Maximum Sparse Coefficients of Obj...

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2015年中国智能自动化学术会议

作者： Zineng Xu Hongjun Li Xiangyu Jin Ching Y.Suen School of Electronic Information Engineering Nantong University Centre for Pattern Recognition and Machine Intelligence Concordia University

Face recognition is an active topic in recognition systems, while face occlusion is one of the most challenging problems for recognition. Recently, robust sparse coding achieved the state-of-the-art performance, especially when dealing with occluded images. However, robust sparse coding is known that only guarantees the coefficient is global sparse when solving sparse coefficients. In this paper,we enable the elements in the object region to approximate global maximum by fitting the distribution of elements in the object region with successful *** efficacy of the proposed approach is verified on publicly available ***, our method can achieve much better performance when the training samples are limited.

关键词： Face recognition Maximum sparse coefficient Occlusion

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An occupation time related potential measure for diffusion processes

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Frontiers of Mathematics in China 2017年第3期12卷 559-582页

作者： Ye CHEN Yingqiu LI Xiaowen ZHOU Hunan Province Cooperative Innovation Center for the Construction and Development of Dongting Lake Ecological Economic Zone and College of Mathematics and Computational Science Hunan University of Arts and Science Changde 415000 China School of Mathematics and Statistics Changsha University of Science and TechnologyChangsha 410114 China Department of Mathematics and Statistics Concordia UniversityMontreal Quebec H3G IMS Canada

In this paper, for homogeneous diffusion processes, the approach of Y. Li and X. Zhou [Statist. Probab. Lett., 2014, 94： 48-55] is adopted to find expressions of potential measures that are discounted by their joint occupation times over semi-infinite intervals （-∞, a） and （a, ∞）. The results are expressed in terms of solutions to the differential equations associated with the diffusions generator. Applying these results, we obtain more explicit expressions for Brownian motion with drift, skew Brownian motion, and Brownian motion with two-valued drift, respectively.

关键词： Laplace transform occupation time potential measure exit time,time-homogeneous diffusion Brownian motion with two-valued drift skew Brownian motion

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On the Attitude Recovery of an Underactuated Spacecraft Using Two Control Moment Gyroscopes

On the Attitude Recovery of an Underactuated Spacecraft Usin...

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Joint 48th IEEE Conference on Decision and Control and 28th Chinese Control Conference

作者： A.R.Mehrabian S.Tafazoli K.Khorasani Department of Electrical and Computer Engineering Concordia University the Canadian Space Agency(CSA) Saint-HubertQC

In recent years there has been a growing interest in development and utilization of small satellites（smallsats）for scientific missions using single or multiple spacecraft（SC）.Due to their small size and low mass, it is not generally possible to equip smallsats with redundant *** case of a failure in the SC’s attitude control actuators, one has to reconfigure the control laws in order to maintain the SC’s attitude by using only the remaining healthy *** this work, an algorithm that is based on nonholonomic control theory and hybrid control systems is presented for recovery of an underactuated axis-symmetric SC（having only two control torque channels）.Our goal is that the recovered SC, in addition to being stabilized, can slew to a desired *** Lyapunov analysis, the asymptotic stability of the system is guaranteed by employing the proposed control *** are performed to demonstrate the performance capabilities of the recovered system.

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Asymptotic SEP of MIMO beamforming in two-hop AF relaying systems

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Science China(Information Sciences) 2012年第2期55卷 377-383页

作者： FU YouHua1,HAN YuJie2,YANG LvXi2,ZHU WeiPing3 & LIU Chen1 1School of Electronic Science and Engineering,Nanjing university of Posts and Telecommunications,Nanjing 210003,China 2School of Information Science and Engineering,Southeast university,Nanjing 210096,China 3Department of Electrical and Computer Engineering,concordia university,Montreal H3G 1M8,Canada 1. School of Electronic Science and Engineering Nanjing University of Posts and Telecommunications Nanjing 210003 China2. School of Information Science and Engineering Southeast University Nanjing 210096 China3. Department of Electrical and Computer Engineering Concordia University Montreal H3G 1M8 Canada

This paper derives an asymptotic average symbol error probability(SEP)expression for multiple-input multiple-output(MIMO)two-hop amplify-and-forward(AF)relay systems with optimal *** analysis at high signal-to-noise ratio(SNR)quantifies the diversity order and array gain,which are valid for any antenna numbers of the terminals and arbitrary channel fading *** is also proved that the system performance is dominated by the relatively degraded one of the two-hop *** results based on the simple expressions provide valuable insights into the performance and practical design considerations of MIMO AF networks.

关键词： MIMO relay networks optimal beamforming symbol error probability(SEP) diversity order

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