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作为合成中介的电影引发建筑的空间异样性探究
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作者 林韬 《美与时代(创意)(上)》 2019年第8期15-17,共3页
电影拍摄将一系列互不关联的要素进行组合,将人眼和摄像机镜头合二为一,从而把人们引入一种更深的知觉。“知觉”由此越来越倾向于艺术与科技之间的渗透。作为合成中介的电影就如同炸药般具有潜在危险性地浓缩着宇宙,碎片的散播、特写... 电影拍摄将一系列互不关联的要素进行组合,将人眼和摄像机镜头合二为一,从而把人们引入一种更深的知觉。“知觉”由此越来越倾向于艺术与科技之间的渗透。作为合成中介的电影就如同炸药般具有潜在危险性地浓缩着宇宙,碎片的散播、特写的空间、慢动作等促使我们看到了事物新结构的外观、表皮与边界。以建筑和电影类比的方式,基于西格蒙德·弗洛伊德的“异样性”理论①,探寻建筑的生成过程及其空间的异样性与多维可能性。 展开更多
关键词 电影 合成中介 异样性 空间 建筑
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日语教学中日本文化的引入 被引量:8
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作者 包志荣 《黑龙江教育学院学报》 2008年第8期186-188,共3页
社会实际上是一个纷繁的文化大系统,语言只是构成文化大系统的要素之一,根据市场经济发展需要及教改方向,在教学中培养学生的文化意识是外语教学的课题之一。
关键词 日本语 教学 日本文化 异样性
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Research on Phenotypic Diversity of Different Populations of Leymus Chinensis in Zhalong Wetlands 被引量:2
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作者 杨晓杰 佟守正 李学花 《Agricultural Science & Technology》 CAS 2011年第9期1372-1375,共4页
[Objective] This paper aimed at revealing the rules of phenotypic variation of Leymus chinensis in Zhalong wetlands and providing the scientific and theoretical bases for devising protection strategies of Leymus chine... [Objective] This paper aimed at revealing the rules of phenotypic variation of Leymus chinensis in Zhalong wetlands and providing the scientific and theoretical bases for devising protection strategies of Leymus chinensis populations in Zhalong National Nature Reserve.[Method] Four phenotypic traits of five Leymus chinensis populations in Zhalong Wetlands were comparison and analysis using principal component analysis method and UPGMA cluster analysis method.[Result] There were significant differences among the four phenotypic traits of five populations,the order of coefficients of variation were node number〉plant height〉leaf width〉leaf length;the order of variation degrees of the populations from large to small was KQH,MD,JZ,ZK,TTG population.Results of principal component analysis suggested that the four traits were all factors led to the phenotypic differences among the populations of Leymus chinensis.Leymus chinensis of five populations were divided into three groups by cluster analysis,MD,JZ and TTG were classified as one group,KQH and ZK population were individually classified as one group.[Conclusion] Leymus chinensis had large-scale phenotypic variations and showed strong adaptability to different habitats,which was very important for selection,breeding of fine varieties and germplasm conservation. 展开更多
关键词 Zhalong Leymus chinensis VARIATION Phenotypic diversity
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Genetic variation of natural and cultured stocks of Paralichthys olivaceus by allozyme and RAPD 被引量:2
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作者 尤锋 张培军 +1 位作者 王可玲 相建海 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2007年第1期78-84,共7页
Population genetics of the left-eyed flounder, Paralichthys olivaceus, including natural and cultured stocks distributed in the coastal waters near Qingdao of eastern maritime China, was analyzed in allozyme and RAPD.... Population genetics of the left-eyed flounder, Paralichthys olivaceus, including natural and cultured stocks distributed in the coastal waters near Qingdao of eastern maritime China, was analyzed in allozyme and RAPD. The results showed that among total 29 gene loci of 15 isozymes, 9 and 7 were po- lymorphic in natural and cultured stocks, respectively. The status of genetic diversity in P. olivaceus is low in terms of polymorphic loci in chi-square test and genetic departure index of Hardy-Weinberg equi- librium. More alleles in IDHP, CAT, GDH and Ldh-C allozymes were found in the fish, which could be used as markers in assortive breeding and distinguishing stock, population or species evolution. Total 88 and 86 RAPD bands ranging from 200 to 2 500 bp were recognized individually in average of 7.8–8.0 bands per primer. The genetic diversity in cultured stock is lower than that in natural ones showing an ob- viously decreasing genetic divergence. Therefore, effective countermeasures must be taken to protect ge- netic resources of marine cultured fishes. The 2 markers have their own pros and cons. Combining the 2 markers to investigate the genetic variation of populations is suggested. The results provide basic data of this flounder and they are useful for studying genetic improvement and genetic resources of the fish. 展开更多
关键词 Paralichthys olivaceus genetic variation natural and cultured stocks ALLOZYME RAPD
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Epiphytic bacterial communities on two common submerged macrophytes in Taihu Lake: diversity and host-specificity 被引量:16
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作者 何聃 任丽娟 吴庆龙 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2012年第2期237-247,共11页
Leaves of terrestrial and aquatic plants are home to a wide diversity of bacterial species. However, the diversity and variability of epiphytic bacteria on their submerged plant hosts remains poorly understood. We inv... Leaves of terrestrial and aquatic plants are home to a wide diversity of bacterial species. However, the diversity and variability of epiphytic bacteria on their submerged plant hosts remains poorly understood. We investigated the diversity and composition of epiphytic bacteria from two common submerged macrophytes: Vallisneria natans and Hydrilla verticillata in Taihu Lake, Jiangsu, China, using methods of terminal restriction fragment length polymorphisms (T-RFLP) and clone library analyses targeted at bacterial 16S rRNA genes. The results show that: (1) the libraries of the two waterweeds contain wide phylogenetic distribution of bacteria, and that the sequences of the two libraries can be separated into 93 OTUs (at 97% similar value); (2) Betaproteobacteria, including Burkholderiales, was the most abundant bacterial group on both plants. Cyanobacteria and Gammaproteobacteria were the second largest groups on V. natans and H. verticillata, respectively. Both clone libraries included some sequences related to those of methanotrophs and nitrogen-fixing bacteria; (3) Cluster analysis of the T-RFLP profiles showed two distinct clusters corresponding to the two plant populations. Both ANOSIM of the T-RFLP data and Libshuff analysis of the two clone libraries indicated a significant difference in epiphytic bacterial communities between the two plants. Therefore, the epiphytic bacterial communities on submerged macrophytes appear to be diverse and host-specific, which may aid in understanding the ecological functions of submerged macrophytes in general. 展开更多
关键词 epiphytic bacterium submerged macrophyte HOST-SPECIFICITY PHYLLOSPHERE
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Experimental study on dynamic elastic parameters of coal samples 被引量:7
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作者 Wu Haibo Dong Shouhua +2 位作者 Li Donghui Huang Yaping Qi Xuemei 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2015年第3期447-452,共6页
Dynamic elastic parameters of coal are closely linked to crack characteristics and are lithology indicators in seismic exploration. This experimental study measured ultrasonic wave velocity of coal samples considering... Dynamic elastic parameters of coal are closely linked to crack characteristics and are lithology indicators in seismic exploration. This experimental study measured ultrasonic wave velocity of coal samples considering both parallel(90°) and perpendicular(0°) to bedding planes, and then calculated the dynamic elastic parameters(Edand ld) and their anisotropy values(AEdand Ald). The variations of Edand ld,as well as AEdand Aldwere analyzed under various confining stresses. The results show that: Firstly, a critical confining pressure exists, and significant variation in the parameters can be seen below this point and weak variation appears above it. Secondly, a positive correlation exists between Edand the square of P-wave velocity(VP2), and between AEdand the P-wave velocity anisotropy(AEP) as well; however, there is no clear correlation between ldand P-wave velocity(VP). Thirdly, according to the major controlling factors of anisotropy, the coal samples with different Edand ldas well as AEdand Aldcan be divided into two types: one is mainly controlled by bedding and cracks and the other one is mainly controlled by differences of mineral compositions in directions. Consequently, this study can provide theoretical basis for future research on the dynamic elastic parameters and anisotropy of coal. 展开更多
关键词 Confining pressure P-wave velocity Dynamic Young's modulus Dynamic Poisson's ratio Anisotropy
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Genetic variation in two sea cucumber (Apostichopus japonicus) stocks revealed by ISSR markers 被引量:3
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作者 姚冰 胡晓丽 +2 位作者 包振民 陆维 胡景杰 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2007年第1期91-96,共6页
Sea cucumber Apostichopus japonicus samples were collected in Changdao, Penglai (PL), 27 individuals, and Lingshandao, Qingdao (QD), 30 individuals, in the Shandong Peninsula, China. Ten SSR primers were used to asses... Sea cucumber Apostichopus japonicus samples were collected in Changdao, Penglai (PL), 27 individuals, and Lingshandao, Qingdao (QD), 30 individuals, in the Shandong Peninsula, China. Ten SSR primers were used to assess the genetic variation and relationship between and within the two stocks. Respectively, for each stock, the percentage of polymorphic bands was 85.2% and 86.9%; the gene diver- sity was 0.360 5 and 0.342 8; and the Shannon’s information index was 0.515 0 and 0.499 0. At species level, the percentage of polymorphic bands was 92.2%, the total gene diversity was 0.378 9 and the Shannon’s information index was 0.550 4. The coefficient of overall genetic differentiation and the ge- netic distances between the stocks were also calculated to be 0.073 0 and 0.079 6 using the POPGENE program. Results show that the genetic diversity of the two stocks is still large but the genetic distance between the two stocks is close. A dendrogram was constructed for the 57 individuals from the two stocks, showing that the genetic structure was unitary for PL stock but complex for QD stock. 展开更多
关键词 sea cucumber Apostichopusjaponicus ISSR STOCK genetic diversity
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Analysis of molecular variation in porcine reproductive and respiratory syndrome virus in China between 2007 and 2012 被引量:2
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作者 Yuhang Cao Hongsheng Ouyang +4 位作者 Mingjun Zhang Fuwang Chen Xin Yang Daxing Pang Linzhu Ren 《Virologica Sinica》 SCIE CAS CSCD 2014年第3期183-188,共6页
In the present study, 89 porcine reproductive and respiratory syndrome virus(PRRSV) isolates in China during 2007 to 2012 were randomly selected from the GenBank genetic sequence database. Evolutionary characteristics... In the present study, 89 porcine reproductive and respiratory syndrome virus(PRRSV) isolates in China during 2007 to 2012 were randomly selected from the GenBank genetic sequence database. Evolutionary characteristics of these isolates were analyzed based on the sequences of non-struc-tural protein 2(Nsp2) and glycoprotein 5(GP5). The genetic variations of the isolates were also compared with six representative strains. The results showed that a high degree of genetic diversity exists among the PRRSV population in China. Highly pathogenic PRRSV isolates, with a discon-tinuous deletion of a 30 amino acid residue in the Nsp2 region, remained the most dominant virus throughout 2007–2012 in China. Owing to the extensive use of representative vaccine strains, natu-ral recombination events occurred between strains. Three isolates – HH08, DY, and YN-2011 – were more closely related to vaccine strains than the other isolates. Both YN-2011 and DY were the evolu-tionary products of recombination events between strains SP and CH-1R. The results of the present study provide useful information for the epidemiology of PRRSV as well as for vaccine development. 展开更多
关键词 porcine reproductive and respiratory syndrome virus(PRRSV) open reading frame(ORF) non-structural protein 2(Nsp2) glycoprotein 5(GP5) recombination
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The Particularity of Identity in Amin Maalouf' s Ports of Call
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作者 Alhaj Mohammad Sumaya 《Sino-US English Teaching》 2014年第9期707-713,共7页
This study explores the intricate situation of the coexistence of different identities in Amin Maalouf' s Ports of Call (1996). It contends that identity is complex, flux, and not limited to what is inherited; it i... This study explores the intricate situation of the coexistence of different identities in Amin Maalouf' s Ports of Call (1996). It contends that identity is complex, flux, and not limited to what is inherited; it is rather a psychological, political, and social amalgamation. Thus, each individual has a unique and particular identity, which is completely different from the others'. This study is a theoretical and analytical survey of Maalouf's Ports of Call. It aims at proving that this novel is an example that Maalouf provides to show the challenges that characters of different identities face, and the obstacles that hinder them from assimilation. The argument is mainly based on Edward Said's theories that have opened up discussions about Otherness and multiculturalism, alongside with other postcolonial critics, such as Homi Bhabha. Maalouf's book In the Name of Identity: Violence and the Need to Belong (1996) is also integral to this study. The study concludes that it might be possible for people, in parallel with the characters of the novel, to challenge the identity predicament that the world is witnessing nowadays, and accept diversities as a way of life, rather than a reason for waging wars. 展开更多
关键词 Amin Maalouf Ports of Call IDENTITY MULTICULTURALISM
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Isolation and identification of bacteria associated with the surfaces of several algal species 被引量:4
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作者 王子峰 肖天 +2 位作者 逄少军 刘敏 岳海东 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2009年第3期487-492,共6页
We conducted this study to assess the diversity of bacteria associated with the surfaces of algae based on 16S rDNA sequence analyses.Twelve strains of bacteria were obtained from the surfaces of the following four sp... We conducted this study to assess the diversity of bacteria associated with the surfaces of algae based on 16S rDNA sequence analyses.Twelve strains of bacteria were obtained from the surfaces of the following four species of algae:Gracilaria textorii,Ulva pertusa,Laminaria japonica,and Polysiphonia urceolata.The isolated strains of bacteria can be divided into two groups:Halomonas and Vibrio,in physiology,biochemical characteristics and 16S rDNA sequence analyses.The phylogenetic tree constructed based on 16S rDNA sequences of the isolates shows four obvious clusters,Halomonas venusta,Vibrio tasmaniensis,Vibrio lentus,and Vibrio splendidus.Isolates from the surface of P.urceolata are more abundant and diverse,of which strains P9 and P28 have a 16S rDNA sequence very similar(97.5%-99.8%) to that of V.splendidus.On the contrary,the isolates from the surfaces of G.textorii,U.pertusa and L.japonica are quite simple and distribute on different branches of the phylogenetic tree.In overall,the results of this study indicate that the genetic relationships among the isolates are quite close and display a certain level of host species specificity,and alga-associated bacteria species are algal species specific. 展开更多
关键词 epiphytic bacteria ALGAE 16S rRNA gene PHYLOGENY
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Spatial Variability of Soil Properties at Capulin Volcano,New Mexico,USA:Implications for Sampling Strategy 被引量:38
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作者 D.C.WEINDORF 《Pedosphere》 SCIE CAS CSCD 2010年第2期185-197,共13页
Non-agricultural lands are surveyed sparsely in general.Meanwhile,soils in these areas usually exhibit strong spatial variability which requires more samples for producing acceptable estimates.Capulin Volcano National... Non-agricultural lands are surveyed sparsely in general.Meanwhile,soils in these areas usually exhibit strong spatial variability which requires more samples for producing acceptable estimates.Capulin Volcano National Monument,as a typical sparsely-surveyed area,was chosen to assess spatial variability of a variety of soil properties,and furthermore,to investigate its implications for sampling design.One hundred and forty one composited soil samples were collected across the Monument and the surrounding areas.Soil properties including pH,organic matter content,extractable elements such as calcium (Ca),magnesium (Mg),potassium (K),sodium (Na),phosphorus (P),sulfur (S),zinc (Zn),and copper (Cu),as well as sand,silt,and clay percentages were analyzed for each sample.Semivariograms of all properties were constructed,standardized,and compared to estimate the spatial variability of the soil properties in the area.Based on the similarity among standardized semivariograms,we found that the semivariograms could be generalized for physical and chemical properties,respectively.The generalized semivariogram for physical properties had a much greater sill value (2.635) and effective range (7 500 m) than that for chemical properties.Optimal sampling density (OSD),which is derived from the generalized semivariogram and defines the relationship between sampling density and expected error percentage,was proposed to represent,interpret,and compare soil spatial variability and to provide guidance for sample scheme design.OSDs showed that chemical properties exhibit a stronger local spatial variability than soil texture parameters,implying more samples or analysis are required to achieve a similar level of precision. 展开更多
关键词 generalized semivariogram GIS optimal sampling density sampling design
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CLINICAL AND GENETIC ANALYSIS OF THREE FAMILIES WITH FAMILIAR AMYLOID POLYNEUROPATHY 被引量:3
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作者 Yan-feng Li Hou Ng +1 位作者 Iok Sun U Waii Leong 《Chinese Medical Sciences Journal》 CAS CSCD 2008年第4期230-233,共4页
Objective To study the clinical and genetic features of familiar amyloid polyneuropathy (FAP). Methods Three families of suspected FAP in China mainland and Macao were investigated on aspects of clinical manifestation... Objective To study the clinical and genetic features of familiar amyloid polyneuropathy (FAP). Methods Three families of suspected FAP in China mainland and Macao were investigated on aspects of clinical manifestations, histological features, and gene analysis. Results All the 3 families had the clinical features of sensory and motor polyneuropathies, and notable vegetative nerve involvements. Affected cases of one family had ultrasound proved cardiomyopathy. Histological studies showed amyloid deposition in all the biopsy tissues of the affected cases of the 3 families, and anti-transthyretin antisera staining was positive in 3 cases of one family. Gene analysis confirmed that mutation types were amyloidogenic transthyretin (ATTR) Val30Met, Phe33Val, and Gly67Glu in the 3 families respectively. The ATTR Gly67Glu family had a shorter survival time due to the heart involvement compared with the other 2 families. Conclusion FAP is an autosomal dominant inherited disease, with its clinical manifestations related to the type of genetic mutation. 展开更多
关键词 familiar amyloid polyneuropathy AMYLOIDOSIS gene mutation
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Stress sensitivity of coal samples in terms of anisotropy
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作者 Jun-Jian WANG Da-Zhen TANG +2 位作者 Hao XU Jie YI Yan-Jing YI 《Journal of Coal Science & Engineering(China)》 2013年第2期203-209,共7页
The permeability and porosity of coal seams are anisotropic, and the variation of confining stress may induce deformation in coal samples. In order to study these characteristics, experiments and model analyses were c... The permeability and porosity of coal seams are anisotropic, and the variation of confining stress may induce deformation in coal samples. In order to study these characteristics, experiments and model analyses were conducted to understand the behaviors of anisotropic stress sensitivity of lean coal samples. The results showed as the closure of cleats and the generation of micro-cracks, the strong stress sensitivity of coal samples and the discrete changes in porosity were caused by confining pressure changes. In the compression period, the anisotropy trend first increased, and then decreased. In the direction perpendicular to the bedding plane, the permeability decrease rate and the irreversible damage rate were the highest. In the direction parallel to the cleats, permeability recovery rate was higher and the irreversible damage rate was lower along butt cleats. Compared to the cube root of permeability to porosity, a 1/6 power relationship was proved to be closer to the experiment results, the new relationship had the highest fit level in the face cleat direction, and the lowest fit level in the vertical direction 展开更多
关键词 COAL ANISOTROPY stress sensitivity PERMEABILITY POROSITY
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Experimental study on influence of coal structural anisotropy to gas permeation 被引量:1
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作者 QIAO Yan-zhen 《Journal of Coal Science & Engineering(China)》 2011年第3期360-362,共3页
Based on "true triaxial coal rock permeability of coal sample test system , the permeability under different gas pressure to coal specimen in bedding plane and the vertical bedding directions are tested. The results ... Based on "true triaxial coal rock permeability of coal sample test system , the permeability under different gas pressure to coal specimen in bedding plane and the vertical bedding directions are tested. The results show that coal structural anisotropy has a greater impact on gas permeability properties, differences in experimental coal permeability are roughly one order of magnitude. In view of the differences of the gas flow characteristics in the coal bedding plane and vertical bedding, established series and parallel choked flow model of coal sample gas seepage, and made a theoretical analysis to the influences of the bedding structure to gas permeability properties. 展开更多
关键词 coal structure gas pressure permeability properties
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AFLP analysis of genetic variation among three natural populations of horseshoe crab Tachypleus tridentatus along Chinese coast
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作者 许茜 陈菲 +3 位作者 单锦城 张肇坚 陈彦 柯才焕 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第2期284-289,共6页
The AFLP(amplified fragment length polymorphism) technique was used to analyze and compare the genetic diversity of Tachypleus tridentatus from three south-eastern coastal sites of China(Pingtan,Hong Kong and Beihai).... The AFLP(amplified fragment length polymorphism) technique was used to analyze and compare the genetic diversity of Tachypleus tridentatus from three south-eastern coastal sites of China(Pingtan,Hong Kong and Beihai).Eight pairs of primers generated 361 loci,including 285 polymorphic loci.The ratio of polymorphic loci was 96.97%.Nei's genetic diversity index was 0.420 8 and the Shannon information index was 0.607 5,both of which were higher than that reported for many other arthropods.These results show that the genetic diversity detected was mainly caused by individual differences within a population.Genetic distance showed that the rational division of the three geographic populations of T.tridentatus along the south-eastern coast of China was not significant,in which the genetic distance was not proportional to the geographic distance.All three horseshoe crab populations may belong to a large group,and had a high degree of genetic similarity.The high level of genetic diversity obtained from the present AFLP analysis may be due to the large effective population size of the species in Chinese waters. 展开更多
关键词 Tachypleus tridentatus POPULATION genetic variation AFLP (amplified fragment lengthpolymorphism)
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COST:Coding over Spatial-Temporal Diversity for Low-Duty-Cycle WSNs
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作者 闫宇博 杨盘隆 +2 位作者 张磊 何源 郭得科 《China Communications》 SCIE CSCD 2011年第1期35-42,共8页
In low-duty-cycle wireless sensor networks,designers have to cope with unreliable links and limited communication capacity.In this work,we propose COST,a coding scheme that leverages spatial-temporal diversity to achi... In low-duty-cycle wireless sensor networks,designers have to cope with unreliable links and limited communication capacity.In this work,we propose COST,a coding scheme that leverages spatial-temporal diversity to achieve higher energy efficiency and lower delay of packet transmissions.We particularly address long sleeping intervals in low-duty-cycle networks by exploiting multi-path diversity.Specifically,we propose to employ an erasure-coding scheme to improve reliability.With respect to energy efficiency and delivery timeliness,we formulate the problem in optimal allocation of coded blocks over multiple paths,which is then proved to be NP-hard.We further propose a near-optimal algorithm to solve the allocation problem.Through extensive simulations,we evaluate the impact of network parameters and demonstrate the effectiveness of our proposal. 展开更多
关键词 low-duty-cycle MULTI-PATH CODING wireless sensor network
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The Importance of Developing Intercultural Awareness in the Business English Classroom
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作者 Andreas Winardi 《Sino-US English Teaching》 2015年第12期964-968,共5页
We live in a multicultural world. As a result, we often have to deal with people from a different culture. This is not easy since we may have very different ways of thinking and doing things from the people we meet. W... We live in a multicultural world. As a result, we often have to deal with people from a different culture. This is not easy since we may have very different ways of thinking and doing things from the people we meet. What is considered good in our culture may mean opposite somewhere else. The understanding of cultural distinctions is very crucial in the business world. The businessmen/women who have sufficient cultural knowledge are more likely to be successful in building relationship with their business counterparts than those who do not. This is because the ones who possess such precious knowledge tend to be more adept at avoiding misunderstanding and confusion. Considering the significant contribution of understanding cultural differences to successful business endeavor, the teachers of Business English need to equip their students with knowledge and strategies that they can use to cope with cultural diversity. In this paper, the writer discusses some activities that can be used to develop students' intercultural awareness. 展开更多
关键词 intercultural awareness business English
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Identification of polymorphic allozyme markers for assessing genetic variability in Labeo dyocheilus (McClelland,1839)
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作者 Peyush PUNIA Lalit NARAIN +4 位作者 Vindhya MOHINDRA Anshumala BHARDWAJ Rajeev Kumar SINGH Dhurendra KAPOOR Kuldeep Kumar LAL 《动物学报》 SCIE CAS CSCD 北大核心 2005年第1期167-170,共4页
The Labeo dyocheilus(family Cyprinidae)in-habits fresh water streams at the fo thill regions and is a commercially important food fish.It is native to Afganistan,Pakistan,India,Nepal,Bhutan,Bangladesh,M yanmnar,Cambod... The Labeo dyocheilus(family Cyprinidae)in-habits fresh water streams at the fo thill regions and is a commercially important food fish.It is native to Afganistan,Pakistan,India,Nepal,Bhutan,Bangladesh,M yanmnar,Cambodia and Thailand(Froese and Pauly,2003).In India,the species in-habits the Indus,Ganges and Mahanadi river sys-terns.It is identified as a potential cultivable species and has considerable significance for the fishery of these regions.L.dyocheilus has been categorized as a vulnerable fish due to declining commercial catches in India(Mahanta et a1.,1994).At present the fishery is supported through capture from natural sources.To achieve domestication,various aspects of captive breeding and propagation are being studied. 展开更多
关键词 Labeo dyocheilus Polymorphic allozyme Genetic variability
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Microsatellite analysis of variation among wild, domesticated, and genetically improved populations of blunt snout bream (Megalobrama amblycephala) 被引量:3
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作者 Shou-Jie TANG Si-Fa LI +1 位作者 Wan-Qi CAI Yan ZHAO 《Zoological Research》 CAS CSCD 北大核心 2014年第2期108-117,共10页
In the present study, the genetic diversity of one selected strain (Pujiang No. 1), two domesticated populations (GA and HX) and four wild populations (LZ, YN, SS and JL) of blunt snout bream (Megalobrama ambly... In the present study, the genetic diversity of one selected strain (Pujiang No. 1), two domesticated populations (GA and HX) and four wild populations (LZ, YN, SS and JL) of blunt snout bream (Megalobrama amblycephala) was analyzed using 17 microsatellite markers. The results showed that an average of 4.88-7.65 number of alleles (A); an average of 3.20-5.33 effective alleles (Ne); average observed beterozygosity (Ho) of 0.6985-0.9044; average expected beterozygosity (He) of 0.6501--0.7805; and the average polymorphism information content (PIC) at 0.5706-0.7226. Pairwise FST value between populations ranged from 0.0307-0.1451, and Nei's standard genetic distance between populations was 0.0938-0.4524. The expected heterozygosities in the domesticated populations (GA and HX) were significantly lower than those found in three wild populations (LZ, SS and JL), but no difference was detected when compared with the wild YN population. Likewise, no difference was found between the four wild populations or two domesticated populations. The expected heterozygosity in Pujiang No. 1 was higher than the two domesticated populations and lower than the four wild populations. Regarding pairwise Fsr value between populations, permutation test P-values were significant between the GA, HX and PJ populations, but not between the four wild populations. These results showed that the expected beterozygosity in the selected strain of blunt snout bream, after seven generations of selective breeding, was lower than that of wild populations, but this strain retains higher levels of genetic diversity than domesticated populations. The genetic differences and differentiation amongst wild populations, domesticated populations and the genetically improved strain of blunt snout bream will provide important conservation criteria and guide the utilization of germplasm resources. 展开更多
关键词 Blunt snout bream Genetic variation MicrosateUite Wild population Domesticated population Genetically improved strain
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Asynchronous cooperative transmission scheme using linear dispersion code
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作者 高明 Ge Jianhua +1 位作者 Han Chunlei Chi Kaikai 《High Technology Letters》 EI CAS 2010年第2期138-142,共5页
The cooperative diversity schemes can effectively create a virtual antenna array for path fading combating multiin wireless channels. However, a lot of cooperative diversity schemes require perfect synchronization whi... The cooperative diversity schemes can effectively create a virtual antenna array for path fading combating multiin wireless channels. However, a lot of cooperative diversity schemes require perfect synchronization which is, in practice, difficult and even impossible to be realized. In this paper, we propose an asynchronous cooperative diversity scheme based on the linear dispersion code (LDC). By adding the zero padding (ZP) between linear dispersion codewords, our scheme mitigates the effect of asynchronism effectively. The length of ZP is decided by relative timing errors between different relays. Besides, an easy decoding method of our scheme is given in this paper by restructuring the stacked channel matrix. 展开更多
关键词 linear dispersion code (LDC) asynchronization cooperative diversity zero padding (ZP) RELAY
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