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The grouping characteristics of sea waves in the Shijiu Port 被引量:2
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作者 Yu Yuxiu and Liu Shuxue Dalian University of Technology, Dalian, 116024, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1991年第3期451-461,共11页
A review concerning the methods of studying and describing wave groups is presented in this paper. After analysing 78 field records collected in the Shijiu Port, China, the measured parameters of wave groups and some ... A review concerning the methods of studying and describing wave groups is presented in this paper. After analysing 78 field records collected in the Shijiu Port, China, the measured parameters of wave groups and some factors describing wave groupness and their variations are given. Moreover, these results are compared with those of theory. 展开更多
关键词 The grouping characteristics of sea waves in the Shijiu Port LENGTH
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Population sizes and group characteristics of Siberian Crane(Leucogeranus leucogeranus) and Hooded Crane(Grus monacha) in Poyang Lake Wetland 被引量:3
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作者 Ming-Qin SHAO Hong GUO +1 位作者 Jian-Hong JIANG 《Zoological Research》 CAS CSCD 北大核心 2014年第5期373-379,共7页
Both the Siberian Crane(Leucogeranus leucogeranus) and Hooded Crane(Grus monacha) have limited population sizes and are considered endangered by domestic Chinese and international agencies.To document the current size... Both the Siberian Crane(Leucogeranus leucogeranus) and Hooded Crane(Grus monacha) have limited population sizes and are considered endangered by domestic Chinese and international agencies.To document the current size of their respective populations and characterize their groups,between October 2012 and April 2013 we undertook fieldwork at four nature reserve areas within the Poyang Lake wetlands.We divided Poyanghu National Nature Reserve(PYH) into the Wucheng(PWC) and Hengfeng areas(PHF),because each are each located in different counties.Our fieldwork showed that the Siberian Crane occurred mainly in PYH(364 in the PHF,158 in the PWC) and the Nanjishan Wetland National Nature Reserve(NJS,with 200 individuals).The Hooded Crane was mainly distributed in PYH(302 in the PHF and 154 in the PWC).Family groups accounted for more than 50% of the total number of groups among both species,with Hooded Cranes forming more family groups than Siberian Cranes.Typically,these groups were formed of two adults with one offspring(Siberian Crane),and two adults with two offspring(Hooded Crane),with the mean family group size of the Siberian Crane and Hooded Crane being respectively 2.65±0.53(n=43) and 3.09±0.86(n=47) individuals per group.The mean collective group size of the Siberian Crane and Hooded Crane included 28.09±24.94(n=23) and 28.94±27.97(n=16) individuals per group,respectively,with the proportion of juveniles among Hooded Cranes being more than double that seen among the Siberian Cranes. 展开更多
关键词 Siberian Crane Hooded Crane Group characteristics Poyang Lake wetland
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Geochemical Characteristics of Proterozoic Mafic Dykes from the Bomdila Group of Rocks, NE Lesser Himalaya, India
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作者 Shaik A Rashid Naqeebul Islam 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第S1期122-,共1页
The mafic dykes from the Paleoproterozoic Bomdila Group of metasedimentary rocks,Arunachal Pradesh,NE Lesser Himalaya,India have been analyzed for major and trace elements geochemistry essentially to understand their
关键词 INDIA NE Lesser Himalaya Geochemical characteristics of Proterozoic Mafic Dykes from the Bomdila Group of Rocks
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The analysis of migrant workers social security
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作者 Huang Can-hua 《International English Education Research》 2015年第6期101-103,共3页
National development proved that the transfer of rural surplus labor force to towns is a common phenomenon of industrialization and urbanization with the system, and the generation of migrant workers is the based on d... National development proved that the transfer of rural surplus labor force to towns is a common phenomenon of industrialization and urbanization with the system, and the generation of migrant workers is the based on dual household registration management system in China's social management system under the special groups. For a long time, the edge of the migrant workers living in the city, become second-class citizens of the city, not only discrimination in employment and all aspects of life, but also lack in social rights, the main performance is the lack of social security. In urban employment for the urban prosperity, the economic development of hard work,added some job vacancy city, become a indispensable workforce urban construction and development, however, cannot and town worker also enjoy social security, this not only is the embodiment of the social injustice, the long down will also hinder the development of economy,and even threaten social stability. Therefore, the problem of social security of peasant workers should and we should pay more attention to the problem. 展开更多
关键词 Migrant workers Group characteristics Social security.
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Algae functional group characteristics in reservoirs and lakes with different trophic levels in northwestern semi-humid and semi-arid regions in China 被引量:7
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作者 Jinsuo Lu Zhe Yang Ying Zhang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2018年第2期166-173,共8页
In order to study the differences in algae species and their biomass in water bodies in a region, three reservoirs and two lakes at the center of Guanzhong Plain were chosen to identify algae functional groups, measur... In order to study the differences in algae species and their biomass in water bodies in a region, three reservoirs and two lakes at the center of Guanzhong Plain were chosen to identify algae functional groups, measure biomass, and assess water quality, from January2013 to December 2014. The water bodies represented different trophic levels: one oligotrophic, three mesotrophic, and one eutrophic. Based on the Reynolds’ functional groups, they had 10 groups in common—B, P, D, X1, M, MP, F, S1, J, and G, but the algae biomasses and proportions were different. In the oligotrophic reservoir, functional group B reached a peak biomass of 576 × 104 L-1, which accounted for 31.27%. In the eutrophic lake,functional group D reached a peak biomass of 3227 × 104 L-1, which accounted for only13.38%. When samples collected from other water bodies with similar trophic levels were compared, we found differences in the algae species functional groups. The potential reasons for the differences in algae functional group characteristics in the different water bodies in the region were water temperature and nutritional states. 展开更多
关键词 Functional group classifications Lakes and reservoirs Trophic levels Functional group characteristics
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The Group Characteristics of the Owners of Private Businesses in China
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《Social Sciences in China》 1995年第2期61-69,共9页
关键词 The Group characteristics of the Owners of Private Businesses in China OO
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A novel statistically tracked particle swarm optimization method for automatic generation control 被引量:1
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作者 Cheshta JAIN H.K.VERMA L.D.ARYA 《Journal of Modern Power Systems and Clean Energy》 SCIE EI 2014年第4期396-410,共15页
Particle swarm optimization(PSO)is one of the popular stochastic optimization based on swarm intelligence algorithm.This simple and promising algorithm has applications in many research fields.In PSO,each particle can... Particle swarm optimization(PSO)is one of the popular stochastic optimization based on swarm intelligence algorithm.This simple and promising algorithm has applications in many research fields.In PSO,each particle can adjust its‘flying’according to its own flying experience and its companions’flying experience.This paper proposes a new PSO variant,called the statistically tracked PSO,which uses group statistical characteristics to update the velocity of the particle after certain iterations,thus avoiding localminima and helping particles to explore global optimum with an improved convergence.The performance of the proposed algorithm is tested on a deregulated automatic generation control problem in power systems and encouraging results are obtained. 展开更多
关键词 Statistically tracked particle swarm optimization(STPSO) Group statistical characteristics Deregulated automatic generation control(AGC)
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The Normalizer Property for Integral Group Rings of Holomorphs of Finite Groups with Trivial Center
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作者 Jin Ke HAI Yi Xin ZHU 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2020年第4期401-406,共6页
Let G=Hol(H)be the holomorph of a finite group H.If there is a prime q dividing|H|such that every q-central automorphism of H is inner and Z(H)=1,then every Coleman automorphism of G is inner.In particular,the normali... Let G=Hol(H)be the holomorph of a finite group H.If there is a prime q dividing|H|such that every q-central automorphism of H is inner and Z(H)=1,then every Coleman automorphism of G is inner.In particular,the normalizer property holds for G. 展开更多
关键词 Coleman automorphisms characteristically simple group normalizer property
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Coleman Automorphisms of Extensions of Finite Characteristically Simple Groups by Some Finite Groups
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作者 Jinke Hai Lele Zhao 《Algebra Colloquium》 SCIE CSCD 2021年第4期561-568,共8页
Let G be an extension of a finite characteristically simple group by an abelian group or a finite simple group.It is shown that every Coleman automorphism of G is an inner automorphism.Interest in such automorphisms a... Let G be an extension of a finite characteristically simple group by an abelian group or a finite simple group.It is shown that every Coleman automorphism of G is an inner automorphism.Interest in such automorphisms arises from the study of the normalizer problem for integral group rings. 展开更多
关键词 characteristically simple group Coleman automorphism normalizer property
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Identification of characteristic plant co-occurrences in neotropical secondary montane forests
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作者 Miguel D.Mahecha Alfredo Martı´nez +2 位作者 Holger Lange Markus Reichstein Erwin Beck 《Journal of Plant Ecology》 SCIE 2009年第1期31-41,共11页
Aims Inferring environmental conditions from characteristic patterns of plant co-occurrences can be crucial for the development of conservation strategies concerning secondary neotropical forests.However,nomethodologi... Aims Inferring environmental conditions from characteristic patterns of plant co-occurrences can be crucial for the development of conservation strategies concerning secondary neotropical forests.However,nomethodological agreement has been achieved so far regarding the identification and classification of characteristic groups of vascular plant species in the tropics.This study examines botanical and,in particular,statistical aspects to beconsidered in such analyses.Based on these,we propose a novel data-driven approach for the identification of characteristic plantco-oc currences in neotropical secondary mountain forests.Methods Floristic inventory data were gathered in secondary tropical mountain forests in Ecuador.Vegetation classification was performed by coupling locally adaptive isometric feature mapping,a non-linear ordination method and fuzzy-c-means clustering.This approach was designed for dealing with underlying non-linearities and uncertainties in the inventory data.Important Findings The results indicate that the applied non-linear mapping in combination with fuzzy classification of species occurrence allows an effective identification of characteristic groups of co-occurring species as fuzzy-defined clusters.The selected species indicated groups representing characteristic life-form distributions,as they correspond to various stages of forest regeneration.Combining the identified‘characteristic species groups’with meta-information derived from accompanying studies indicated that the clusters can also be related to habitat conditions.In conclusion,we identified species groups either characteristic of different stages of forest succession after clear-cutting or of impact by fire or a landslide.We expect that the proposed data-mining method will be useful for vegetation classification where no a priori knowledge is available. 展开更多
关键词 secondary tropical mountain forests characteristic species groups non-linear ordination fuzzy-c-means clustering Ecuador
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The Projective Cover of the Trivial Representation for a Finite Group of Lie Type in Defining Characteristic
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作者 Shigeo Koshitani Jürgen Müller 《Algebra Colloquium》 SCIE CSCD 2017年第3期439-452,共14页
We give a lower bound of the Loewy length of the projective cover of the trivial module for the group algebra kG of a finite group G of Lie type defined over a finite field of odd characteristic p, where k is an arbit... We give a lower bound of the Loewy length of the projective cover of the trivial module for the group algebra kG of a finite group G of Lie type defined over a finite field of odd characteristic p, where k is an arbitrary field of characteristic p. The proof uses Auslander-Reiten theory. 展开更多
关键词 modular representations projective cover of trivial module finite groups ofLie type in defining characteristic
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Characteristic conditions-for strongly continuous groups of linear operators on a Hilbert space
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作者 LIU KangshengDepartment of Applied Mathematics, Zhejiang University, Hangzhou 310027, China 《Chinese Science Bulletin》 SCIE EI CAS 1999年第14期1344-1344,共1页
IN 1932, Stone [1] gave the first result concerning C<sub>0</sub> semigroups generated by an unbounded operator,which says that a linear operator is the infinitesimal generator of a C<sub>0</sub&g... IN 1932, Stone [1] gave the first result concerning C<sub>0</sub> semigroups generated by an unbounded operator,which says that a linear operator is the infinitesimal generator of a C<sub>0</sub> group of unitary operators on a Hilbert space if and only if it is skew-adjoint. This result has been applied extensively to linear partial differential equations (PDEs) with a law of conservation. Hille [2] then discovered the generation theorem of the Hille-Yosida type for a C<sub>0</sub> group on a Banach space. There are also some conditions under which a C<sub>0</sub> semigroup on a Banach space can be embedded in a C<sub>0</sub> group. We refer the readers to ref. [3] for details of the results mentioned above. 展开更多
关键词 Characteristic conditions-for strongly continuous groups of linear operators on a Hilbert space PDES
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