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Divergences in Perceptions as for Oral Activity in Morocco
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作者 Sana SAKALE 《Sino-US English Teaching》 2018年第1期8-13,共6页
This article tries to find out the few discrepancies between the teachers and their scholars as to oral activity, which shows that scholars' expectations and needs are not quite responded to. The versions chosen as a... This article tries to find out the few discrepancies between the teachers and their scholars as to oral activity, which shows that scholars' expectations and needs are not quite responded to. The versions chosen as a sample for this study come from different schools in the academy of Rabat Sal~ Zemmour Zaer area and belong to three different educational levels including common core, first year, and second year in addition to a total number of 40 teachers who have contributed to this research throughout the whole process. This research has relied on different instruments to collect the data including questionnaires, interviews, and class observation grids. Results showed that scholars' perceptions highly favour thematic variety. Findings also reported match findings of previous research in highlighting the importance of using tech facilities and multimedia to improve oral activity. 展开更多
关键词 different educational levels divergences in dealing with oral activity expectations PERCEPTIONS
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Allele-specific expression analyses reveal immune divergences between ibex and goat species
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作者 Zhi-Rui Yang Jia-Xin Li +12 位作者 Zhu-Qing Zheng Chen Zhao Yu Wang Ming Li Hojjat Asadollahpour Nanaei Xue-Lei Dai Yun-Jia Li Ran Li Chun-Na Cao Mao Li Yu Jiang Wen-Xin Zheng Xi-Hong Wang 《Zoological Research》 SCIE CAS CSCD 2022年第4期671-674,共4页
DEAR EDITOR,Understanding the different immune responses of wild and domestic caprid species is critical for addressing certain zoonotic diseases.In this study,we generated blood transcriptomes of 13 Siberian ibex and... DEAR EDITOR,Understanding the different immune responses of wild and domestic caprid species is critical for addressing certain zoonotic diseases.In this study,we generated blood transcriptomes of 13 Siberian ibex and domestic goat hybrids and performed allele-specific expression and splicing analyses.Results showed that genes exhibiting significant imbalance between the ibex and goat were highly related to the Toll-like receptor(TLR),antigen recognition,and immune activation pathways.Comparative genomic analysis of the species revealed that immune function-related genes were under strong selection pressure in the domestic goat. 展开更多
关键词 IMMUNE ALLELE divergence
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Phenotypic divergences induced by different residence time in invasive common ragweeds 被引量:1
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作者 Annamaria Fenesi Zoltan Botta-Dukat 《Journal of Plant Ecology》 SCIE 2012年第2期174-181,共8页
Aims Possible shifts in the phenotypic performance along invasive plants’spreading route are rarely examined due to the discontinuous and incomplete records of exotic species.As the invasion history of common ragweed... Aims Possible shifts in the phenotypic performance along invasive plants’spreading route are rarely examined due to the discontinuous and incomplete records of exotic species.As the invasion history of common ragweed(Ambrosia artemisiifolia L.)is well documented in Hungary,its residence time is known for each location.By sampling a sequence of older to more recently established populations,we aimed to determine(i)whether there are phenotypic divergences along the historical spreading route of A.artemisiifolia;(ii)which traits are under selection during the invasion process and(iii)the extent of maternal effects on the individual’s performance.Methods We used a hierarchical sampling design to collect seeds from 64 individuals belonging to eight sites in four residence time categories(seven populations along the historical spreading route of ragweed in Hungary and one recently invaded site in Romania).We selected four large and four small individual plants in each population to control for maternal effects.The offspring were reared in a common garden located in Romania.Five vegetative phenotypic traits were measured at the end of the experiments and used in the subsequent analysis(plant height,basal diameter,number of secondary axes,length of the longest secondary axis and biomass).To summarize the variation of these highly correlated traits,principal component analysis was performed first and then the important components were used in linear mixed effect models.Important Findings The residence time categories were significantly distinguished by the first component,which compresses the variation of all five measured traits.The measures gradually decrease from populations with the longest residence time(introduced more than 65 years ago)towards the most recently established populations(established less than 30 years ago).These differences might reflect the invasion history of the populations:the longer the residence time the higher the chance to develop relevant traits beneficial in invasion process.The size of the mother plant significantly influenced not only the seed mass(inversely)but also the adult performance of its offspring(directly). 展开更多
关键词 Ambrosia artemisiifolia maternal effect phenotypic divergence plant invasion residence time
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Genetically-and environmentally-dependent processes drive interspecific and intraspecific divergence in the Chinese relict endemic genus Dipteronia
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作者 Tao Zhou Xiaodan Chen +6 位作者 Jordi López-Pujol Guoqing Bai Sonia Herrando-Moraira Neus Nualart Xiao Zhang Yuemei Zhao Guifang Zhao 《Plant Diversity》 SCIE CAS CSCD 2024年第5期585-599,共15页
China is a hotspot of relict plant species that were once widespread throughout the Northern Hemisphere.Recent research has demonstrated that the occurrence of long-term stable refugia in the mountainous regions of ce... China is a hotspot of relict plant species that were once widespread throughout the Northern Hemisphere.Recent research has demonstrated that the occurrence of long-term stable refugia in the mountainous regions of central and south-western China allowed their persistence through the late Neogene climate fluctuations.One of these relict lineages is Dipteronia,an oligotypic tree genus with a fossil record extending to the Paleocene.Here,we investigated the genetic variability,demographic dynamics and diversification patterns of the two currently recognized Dipteronia species(Dipteronia sinensis and D.dyeriana).Molecular data were obtained from 45 populations of Dipteronia by genotyping three cpDNA regions,two single copy nuclear genes and 15 simple sequence repeat loci.The genetic study was combined with niche comparison analyses on the environmental space,ecological niche modeling,and landscape connectivity analysis.We found that the two Dipteronia species have highly diverged both in genetic and ecological terms.Despite the incipient speciation processes that can be observed in D.sinensis,the occurrence of long-term stable refugia and,particularly,a dispersal corridor along Daba Shan-west Qinling,likely ensured its genetic and ecological integrity to date.Our study will not only help us to understand how populations of Dipteronia species responded to the tectonic and climatic changes of the Cenozoic,but also provide insight into how Arcto-Tertiary relict plants in East Asia survived,evolved,and diversified. 展开更多
关键词 Dipteronia Interspecific/intraspecific divergence Genetic structure Climatic niche divergence Dispersal corridor
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A new species of Discostella guiyangensis sp.nov.(Bacillariophyta,Stephanodiscales)from Guiyang,China:morphology and phylogeny
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作者 Yandan XIANG Fangru NAN +3 位作者 Xudong LIU Shulian XIE John Patrick KOCIOLEK Qi LIU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第4期1312-1324,共13页
We describe a new species of Discostella from Guiyang based on light and scanning electron microscopic observations,as well as molecular analysis.This species is morphologically distinguished from other species by a r... We describe a new species of Discostella from Guiyang based on light and scanning electron microscopic observations,as well as molecular analysis.This species is morphologically distinguished from other species by a relatively smooth and slightly recessed central area with marginal striae of unequal lengths forked near the margin.Marginal fultoportulae and a single rimoportula are situated between every two costae or on the costae.Both morphological characters and the concatenated data of rbc L and SSU rDNA indicate that Discostella guiyangensis is a unique and new species.According to divergence time estimation analysis,Discostella guiyangensis is the oldest species among the Discostella species sequenced currently.In addition,we complement molecular data of Discostella asterocostata and Discostella stelligera. 展开更多
关键词 Discostella MORPHOLOGY molecular analysis divergence time estimation new species
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Influence of Transportation Accessibility on Urban-rural Income Disparity and Its Spatial Heterogeneity
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作者 HUANG Xiaoyan KANG Chenchen +1 位作者 YIN Chun TANG Junqing 《Chinese Geographical Science》 SCIE CSCD 2024年第3期453-467,共15页
Transportation accessibility has been treated as an important means of reducing the urban-rural income disparity.However,only a few studies have examined the effects of different types of transportation accessibility ... Transportation accessibility has been treated as an important means of reducing the urban-rural income disparity.However,only a few studies have examined the effects of different types of transportation accessibility on urban-rural income disparity and their spatial heterogeneity.Based on data from 285 prefecture-level(and above)Chinese cities in 2000,2005,2010,2015,and 2020,this study uses spatial econometric models to examine how highway accessibility and railway accessibility influence the urban-rural income disparity and to identify their spatial heterogeneity.The result reveals that highway accessibility and railway accessibility have‘coreperiphery’ring-like circle structures.The urban-rural income disparity exhibits strong spatial clustering effects.Both highway accessibility and railway accessibility are negatively associated with urban-rural income disparity,and the former having a greater effect size.Moreover,there is a substitution effect between highway accessibility and railway accessibility in the whole sample.Furthermore,these associations differ in geographic regions.In the central region,highway accessibility is more important in reducing the urban-rural income disparity,but its effect is weakened with the increase of railway accessibility.In the western region,railway accessibility has a larger effect on narrowing the urban-rural income disparity,and this effect is strengthened by the increase of highway accessibility.We conclude that improving transportation accessibility is conducive to reducing the urban-rural income disparity but its effect is spatial heterogenetic.Highways and railways should be developed in a coordinated manner to promote an integrated transport network system. 展开更多
关键词 transport accessibility income gap regional divergence spatial heterogeneity urban and rural areas China
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ELLIPTIC EQUATIONS IN DIVERGENCE FORM WITH DISCONTINUOUS COEFFICIENTS IN DOMAINS WITH CORNERS
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作者 Jun CHEN Xuemei DENG 《Acta Mathematica Scientia》 SCIE CSCD 2024年第5期1903-1915,共13页
We study equations in divergence form with piecewise Cαcoefficients.The domains contain corners and the discontinuity surfaces are attached to the edges of the corners.We obtain piecewise C^(1,α) estimates across th... We study equations in divergence form with piecewise Cαcoefficients.The domains contain corners and the discontinuity surfaces are attached to the edges of the corners.We obtain piecewise C^(1,α) estimates across the discontinuity surfaces and provide an example to illustrate the issue regarding the regularity at the corners. 展开更多
关键词 elliptic equations divergence form discontinuous coefficients corner regularity
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Four-to Six-Year Periodic Variation of Arctic Sea-Ice Extent and Its Three Main Driving Factors
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作者 Ping CHEN Jinping ZHAO Xiaoyu WANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第10期1999-2010,共12页
Besides the rapid retreating trend of Arctic sea-ice extent(SIE),this study found the most outstanding low-frequency variation of SIE to be a 4-6-year periodic variation.Using a clustering analysis algorithm,the SIE i... Besides the rapid retreating trend of Arctic sea-ice extent(SIE),this study found the most outstanding low-frequency variation of SIE to be a 4-6-year periodic variation.Using a clustering analysis algorithm,the SIE in most ice-covered regions was clustered into two special regions:Region-1 around the Barents Sea and Region-2 around the Canadian Basin,which were located on either side of the Arctic Transpolar Drift.Clear 4-6-year periodic variation in these two regions was identified using a novel method called“running linear fitting algorithm”.The rate of temporal variation of the Arctic SIE was related to three driving factors:the regional air temperature,the sea-ice areal flux across the Arctic Transpolar Drift,and the divergence of sea-ice drift.The 4-6-year periodic variation was found to have always been present since 1979,but the SIE responded to different factors under heavy and light ice conditions divided by the year 2005.The joint contribution of the three factors to SIE variation exceeded 83%and 59%in the two regions,respectively,remarkably reflecting their dynamic mechanism.It is proven that the process of El Niño-Southern Oscillation(ENSO)is closely associated with the three factors,being the fundamental source of the 4-6-year periodic variations of Arctic SIE. 展开更多
关键词 sea-ice extent periodic variation air temperature sea-ice areal flux Arctic Transpolar Drift ice-drift divergence ENSO
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Geographical Variation in the Advertisement Calls of Leptobrachella ventripunctata(Anura:Megophryidae)in Southwestern China
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作者 Chaobo FENG Tuo SHEN +4 位作者 Lang MU Jing LIU Shize LI Yixin DIAO Haijun SU 《Asian Herpetological Research》 SCIE CSCD 2024年第3期140-151,共12页
In anurans,advertisement calls(ACs)are an essential form of intraspecific communication.This study evaluates geographical variation in the ACs of Leptobrachella ventripunctata in the Guizhou Plateau,southwestern China... In anurans,advertisement calls(ACs)are an essential form of intraspecific communication.This study evaluates geographical variation in the ACs of Leptobrachella ventripunctata in the Guizhou Plateau,southwestern China,and explores correlations between call characteristics,body size,and environmental factors.ACs are simple calls of L.ventripunctata,and apparent differences were observed in the ACs among different geographical populations of L.ventripunctata.The Call duration(CD)revealed a significant positive correlation with altitude and a significant negative correlation with temperature and humidity.Moreover,the Dominant frequency(DF)exhibited a significant negative correlation with altitude and the habitat closure degree and a significant positive correlation with temperature.These variations in ACs between different geographical populations of L.ventripunctata may critically impact the adaptive evolution of species,and the calls may also be relevant for environmental selection. 展开更多
关键词 ANURAN BIOACOUSTICS environmental factors geographical divergence
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Optimization of magnetic field design for Hall thrusters based on a genetic algorithm
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作者 谭睿 杭观荣 王平阳 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第7期82-92,共11页
Magnetic field design is essential for the operation of Hall thrusters.This study focuses on utilizing a genetic algorithm to optimize the magnetic field configuration of SPT70.A 2D hybrid PIC-DSMC and channel-wall er... Magnetic field design is essential for the operation of Hall thrusters.This study focuses on utilizing a genetic algorithm to optimize the magnetic field configuration of SPT70.A 2D hybrid PIC-DSMC and channel-wall erosion model are employed to analyze the plume divergence angle and wall erosion rate,while a Farady probe measurement and laser profilometry system are set up to verify the simulation results.The results demonstrate that the genetic algorithm contributes to reducing the divergence angle of the thruster plumes and alleviating the impact of high-energy particles on the discharge channel wall,reducing the erosion by 5.5%and 2.7%,respectively.Further analysis indicates that the change from a divergent magnetic field to a convergent magnetic field,combined with the upstream shift of the ionization region,contributes to the improving the operation of the Hall thruster. 展开更多
关键词 magnetic field design genetic algorithm divergence angle erosion of discharge channel convergent magnetic field
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Research on aiming methods for small sample size shooting tests of two-dimensional trajectory correction fuse
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作者 Chen Liang Qiang Shen +4 位作者 Zilong Deng Hongyun Li Wenyang Pu Lingyun Tian Ziyang Lin 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期506-517,共12页
The longitudinal dispersion of the projectile in shooting tests of two-dimensional trajectory corrections fused with fixed canards is extremely large that it sometimes exceeds the correction ability of the correction ... The longitudinal dispersion of the projectile in shooting tests of two-dimensional trajectory corrections fused with fixed canards is extremely large that it sometimes exceeds the correction ability of the correction fuse actuator.The impact point easily deviates from the target,and thus the correction result cannot be readily evaluated.However,the cost of shooting tests is considerably high to conduct many tests for data collection.To address this issue,this study proposes an aiming method for shooting tests based on small sample size.The proposed method uses the Bootstrap method to expand the test data;repeatedly iterates and corrects the position of the simulated theoretical impact points through an improved compatibility test method;and dynamically adjusts the weight of the prior distribution of simulation results based on Kullback-Leibler divergence,which to some extent avoids the real data being"submerged"by the simulation data and achieves the fusion Bayesian estimation of the dispersion center.The experimental results show that when the simulation accuracy is sufficiently high,the proposed method yields a smaller mean-square deviation in estimating the dispersion center and higher shooting accuracy than those of the three comparison methods,which is more conducive to reflecting the effect of the control algorithm and facilitating test personnel to iterate their proposed structures and algorithms.;in addition,this study provides a knowledge base for further comprehensive studies in the future. 展开更多
关键词 Two-dimensional trajectory correction fuse Small sample size test Compatibility test KL divergence Fusion bayesian estimation
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Multiple-model GLMB filter based on track-before-detect for tracking multiple maneuvering targets
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作者 CAO Chenghu ZHAO Yongbo 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第5期1109-1121,共13页
A generalized labeled multi-Bernoulli(GLMB)filter with motion mode label based on the track-before-detect(TBD)strategy for maneuvering targets in sea clutter with heavy tail,in which the transitions of the mode of tar... A generalized labeled multi-Bernoulli(GLMB)filter with motion mode label based on the track-before-detect(TBD)strategy for maneuvering targets in sea clutter with heavy tail,in which the transitions of the mode of target motions are modeled by using jump Markovian system(JMS),is presented in this paper.The close-form solution is derived for sequential Monte Carlo implementation of the GLMB filter based on the TBD model.In update,we derive a tractable GLMB density,which preserves the cardinality distribution and first-order moment of the labeled multi-target distribution of interest as well as minimizes the Kullback-Leibler divergence(KLD),to enable the next recursive cycle.The relevant simulation results prove that the proposed multiple-model GLMB-TBD(MM-GLMB-TBD)algorithm based on K-distributed clutter model can improve the detecting and tracking performance in both estimation error and robustness compared with state-of-the-art algorithms for sea clutter background.Additionally,the simulations show that the proposed MM-GLMB-TBD algorithm can accurately output the multitarget trajectories with considerably less computational complexity compared with the adapted dynamic programming based TBD(DP-TBD)algorithm.Meanwhile,the simulation results also indicate that the proposed MM-GLMB-TBD filter slightly outperforms the JMS particle filter based TBD(JMSMeMBer-TBD)filter in estimation error with the basically same computational cost.Finally,the impact of the mismatches on the clutter model and clutter parameter is investigated for the performance of the MM-GLMB-TBD filter. 展开更多
关键词 generalized labeled multi-Bernoulli(GLMB) trackbefore-detect(TBD) jump Markovian system(JMS) K-DISTRIBUTION Kullback-Leibler divergence(KLD)
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Kullback-Leibler Divergence Based ISAC Constellation and Beamforming Design in the Presence of Clutter
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作者 TANG Shuntian WANG Xinyi +1 位作者 XIA Fanghao FEI Zesong 《ZTE Communications》 2024年第3期4-12,共9页
Integrated sensing and communication(ISAC)is regarded as a pivotal technology for 6G communication.In this paper,we employ Kullback-Leibler divergence(KLD)as the unified performance metric for ISAC systems and investi... Integrated sensing and communication(ISAC)is regarded as a pivotal technology for 6G communication.In this paper,we employ Kullback-Leibler divergence(KLD)as the unified performance metric for ISAC systems and investigate constellation and beamforming design in the presence of clutters.In particular,the constellation design problem is solved via the successive convex approximation(SCA)technique,and the optimal beamforming in terms of sensing KLD is proven to be equivalent to maximizing the signal-to-interference-plus-noise ratio(SINR)of echo signals.Numerical results demonstrate the tradeoff between sensing and communication performance under different parameter setups.Additionally,the beampattern generated by the proposed algorithm achieves significant clutter suppression and higher SINR of echo signals compared with the conventional scheme. 展开更多
关键词 constellation design clutter suppression integrated sensing and communications Kullback-Leibler divergence
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Lotic specialization in modern Asian newts(Caudata:Salamandridae):Phylogeny,historical biogeography,and ancestral traits based on combined DNA data
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作者 Yan-Peng Shen Kanto Nishikawa +5 位作者 Jian-Ping Jiang Masafumi Matsui Ding-Qi Rao Natsuhiko Yoshikawa Atsushi Tominaga Daosavanh Sanamxay 《Zoological Research:Diversity and Conservation》 2024年第3期191-200,共10页
Pachytriton,and Paramesotriton,are primarily distributed across East Asia,displaying a broad range of environmental adaptations,including generalists inhabiting both lotic and lentic habitats and lotic specializations... Pachytriton,and Paramesotriton,are primarily distributed across East Asia,displaying a broad range of environmental adaptations,including generalists inhabiting both lotic and lentic habitats and lotic specializations.Despite recent studies on their biogeographic history,how these species adapted to geographical changes remains unclear.In this study,divergence times and reconstructed ancestral traits were estimated based on phylogenetic analysis of mitochondrial and nuclear DNA sequences,totaling 4048 bp.Results indicated that the divergence between lotic-specialized and generalist species occurred during the middle to late Miocene(95% confidence interval(CI):16-13 million years ago(Ma)),correlating with the long-lasting arid period(14-12 Ma)and uplift of the Wuyi-Nanling mountains(15-11 Ma).Ancestral trait reconstruction revealed notable morphological changes associated with the emergence of lotic-specialized lineages.Specifically,male body size increased from 130 mm to 140 mm,and epibranchial traits shifted from thin to thick structures.Additionally,variation in tongue movability and skin texture were observed among lotic species.Each morphological shift is hypothesized to have an ecological basis,facilitating adaptation to specific environmental conditions.Overall,this study represents the first comprehensive attempt to elucidate the evolution of ancestral traits among divergent species of modern Asian newts,providing a deeper understanding of their adaptive responses to historical geographical and climatic changes. 展开更多
关键词 Modern Asian newts PHYLOGENY Divergence time Trait reconstruction
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调查表数据分析中变量选择和判别分析的一些方法及简单比较 被引量:5
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作者 张俊华 方伟武 《中国管理科学》 CSSCI 2000年第S1期229-236,共8页
变量选择和判别分析是调查表数据分析中的两个重要问题.文中描述了我们基于信息理论提出的四种变量选择的新方法,并把这些方法作了简单比较;同时还简要介绍了我们提出的用于判别分析的一种信息理论方法,与前人的工作相比,这里的算... 变量选择和判别分析是调查表数据分析中的两个重要问题.文中描述了我们基于信息理论提出的四种变量选择的新方法,并把这些方法作了简单比较;同时还简要介绍了我们提出的用于判别分析的一种信息理论方法,与前人的工作相比,这里的算法能用于多组样本的情况,而且计算非常简单. 展开更多
关键词 变量选择 判别分析 信息差(information divergence) 统计量
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基于模拟关系的精化检测方法 被引量:2
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作者 王婷 陈铁明 刘杨 《软件学报》 EI CSCD 北大核心 2016年第3期580-592,共13页
精化检测是一种重要的形式化验证方法,将系统实现和性质规约用相同的形式化语言进行建模,如能证明两者间存在某种精化关系,且该关系能够维持性质,可得出系统实现满足性质规约.为验证不同类型的系统性质,traces,stable failures和failure... 精化检测是一种重要的形式化验证方法,将系统实现和性质规约用相同的形式化语言进行建模,如能证明两者间存在某种精化关系,且该关系能够维持性质,可得出系统实现满足性质规约.为验证不同类型的系统性质,traces,stable failures和failures-divergence精化检测方法已被提出.精化检测算法依赖于子集构造,因而其面临状态空间爆炸问题.近年来,已有学者针对NFA语言包含问题提出了基于模拟关系的状态空间消减方法,极大地提高了算法的性能,且该方法能够直接用于traces精化检测.在此基础上,提出了基于模拟关系的stable failures和failuresdivergence精化检测方法.此外,还将精化检测扩展到了时间系统的验证中,提出了基于模拟关系的时间自动机traces精化检测方法.实验结果表明,基于模拟关系的算法效率有很大提高. 展开更多
关键词 精化检测 模拟 FAILURES DIVERGENCE 时间自动机
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UPWIND SCHEME FOR IDEAL 2-D MHD FLOWS BASED ON UNSTRUCTURED MESH 被引量:1
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作者 潘勇 王江峰 伍贻兆 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2007年第1期1-7,共7页
An upwind scheme based on the unstructured mesh is developed to solve ideal 2-D magnetohydrodynamics (MHD) equations. The inviscid fluxes are approximated by using the modified advection upstream splitting method (... An upwind scheme based on the unstructured mesh is developed to solve ideal 2-D magnetohydrodynamics (MHD) equations. The inviscid fluxes are approximated by using the modified advection upstream splitting method (AUSM) scheme, and a 5-stage explicit Runge-Kutta scheme is adopted in the time integration. To avoid the influence of the magnetic field divergence created during the simulation, the hyperbolic divergence cleaning method is introduced. The shock-capturing properties of the method are verified by solving the MHD shock-tube problem. Then the 2-D nozzle flow with the magnetic field is numerically simulated on the unstructured mesh. Computational results demonstrate the effects of the magnetic field and agree well with those from references. 展开更多
关键词 ideal magnetohydrodynamics equation unstructured mesh advection upstream splitting method(AUSM) scheme divergence cleaning
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Description of a new parthenogenetic species of Thalassaphorura (Collembola: Onychiuridae) from East China, with DNA barcoding analyses
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作者 高艳 卜云 《Entomotaxonomia》 CSCD 北大核心 2014年第1期1-7,共7页
Thalassaphorura houtanensis sp. nov. from Shanghai, East China is described. It is similar to T. encarpata (Denis, 1931) in having labial palp of type A and the same pseudocelli formula on the body. It can be distin... Thalassaphorura houtanensis sp. nov. from Shanghai, East China is described. It is similar to T. encarpata (Denis, 1931) in having labial palp of type A and the same pseudocelli formula on the body. It can be distinguished by the shape of unguis, chaetotaxy of labium, maxillary out lobe and ventral tube. It was confirmed as an absolutely parthenogenetic species after a reproduction test in the lab. In addition, the DNA barcoding sequences of this new species were sequenced and analyzed. The intraspecific genetic divergence is 0.18% on average and ranges from zero to 0.46%. 展开更多
关键词 Arthropleona SPRINGTAIL taxonomy genetic divergence REPRODUCTION
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The Difference between Female Characters May and Ellen—Read The Age of Innocence Pure feeling 被引量:1
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作者 李辩 郎婷婷 《海外英语》 2014年第13期174-175,共2页
As the masterpiece of Wharton,The Age of Innocence mainly concentrates on women’s fates in the strict restraint of the New York society.In the novel,Wharton portrays two contrasting female characters—May Welland and... As the masterpiece of Wharton,The Age of Innocence mainly concentrates on women’s fates in the strict restraint of the New York society.In the novel,Wharton portrays two contrasting female characters—May Welland and Ellen Olenska,who are regarded as the most progressive ones among the female figures she has ever created.Scholars,both domestic and abroad,have studied this novel from a raft of perspectives.Most of them have explored the feminist ideas,the conventions of upper-class society,and the protagonist Newland’s perplexity which are embodied in the novel.However,this paper aims to examine the divergences between two female figures—May and Ellen.The exploration of their divergences makes it clear that May is an ideal woman of the 19th century New York while Ellen is an ideal woman of modern society. 展开更多
关键词 The Age of INNOCENCE Edith WHARTON divergences fem
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Analysis of a Wenzhou-Hitting Exceptionally Strong Rainstorm Associated with a Typhoon Inverted Trough in September,1999
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作者 郑峰 《Marine Science Bulletin》 CAS 2010年第1期39-47,共9页
Using T106 numerical products, MM5 simulations in conjunction of Q-vector scheme-computed NCEP results, observations and satellite cloud images, study is undertaken for an exceptionally intense rainstorm event afflict... Using T106 numerical products, MM5 simulations in conjunction of Q-vector scheme-computed NCEP results, observations and satellite cloud images, study is undertaken for an exceptionally intense rainstorm event afflicting the Wenzhou region of Zhejiang province far away from the tropical storm center happening early on the morning of September 4, 1999 (TS9909 hereinafter). Evidence suggests that, like previously-studied typhoons landing in autumn south of Xiamen to the eastern part of Guangdong, TS9909 has an inverted trough in the central south of the coastal belt of Zhejiang province that produces the rainstorm from the meso convective complex (MCC) on the warm, moist shear inside; the time and order of the magnitude of the rainfall are bound up with the development of the pattern of strong Q-vector divergence gradients during the event for the study area; the NE - SW coastline and the unique topography of the Yandang mountains inside the region are favorable for air lifting are the major contributors to the torrential rains. 展开更多
关键词 long-distance-away typhoon rainstorm inverted trough MCC Q-vector divergence gradient
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