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可解饱和群系的一些新刻划
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作者 王坤仁 《四川师范大学学报(自然科学版)》 CAS CSCD 1997年第2期8-13,共6页
在本文中,我们得到了可解饱和群系的若干新刻划.
关键词 可解饱和群 F中心主因子 F正规极大子
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直和群及其子群之间的关系
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作者 王树忠 《哈尔滨商业大学学报(自然科学版)》 CAS 2006年第5期53-54,共2页
给出了直和群的子群的构造,得到了直和群的子群和构成直和群的每个群的内在联系,并研究了直和群的子群的性质.
关键词 和群 同态
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战术Ad hoc网络的一种分群方法 被引量:1
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作者 刘行兵 张聪品 李文林 《广西师范大学学报(自然科学版)》 CAS 北大核心 2008年第3期234-237,共4页
战术Ad hoc网群是按一定编制组成,其群首及成员相对固定。传统的Ad hoc网分群算法对群首和群成员的确立存在随机性,对战术Ad hoc网分群缺乏针对性。提出基于指挥员节点的战术Ad hoc网分群算法,通过规划保证指挥员节点具有最大逻辑编制... 战术Ad hoc网群是按一定编制组成,其群首及成员相对固定。传统的Ad hoc网分群算法对群首和群成员的确立存在随机性,对战术Ad hoc网分群缺乏针对性。提出基于指挥员节点的战术Ad hoc网分群算法,通过规划保证指挥员节点具有最大逻辑编制连接度,群首用递归算法对节点进行相关度计算,其他节点执行跟随算法,确保指挥员节点在成群和运动过程中保持实际上最大连接度,实现战术Ad hoc网的层次结构的划分。 展开更多
关键词 自组网 算法 和群
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时滞Logistic方程非振动解的存在性 被引量:3
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作者 王志成 庚建设 黄立宏 《高校应用数学学报(A辑)》 CSCD 北大核心 1992年第4期517-524,共8页
本文获得了时滞Logistic方程 x'(t)=r(t)x(t)[1-a_1x(g_1(t))-a_2x(g_2(t))]~a,t≥0关于其正平衡状态x=1/(a_1+a_2)存在非振动解的充分条件与充要条件,改进并推广了Aiello中的结果.
关键词 LOGISTIC方程 振动性 和群
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模糊合作对策区间Shapley值法的改进及应用 被引量:9
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作者 王晓艳 殷辉 《计算机工程与应用》 CSCD 2013年第15期60-64,79,共6页
模糊合作对策的收益分配是个复杂问题,受到合作方的风险承担、合作努力、市场竞争、创新贡献和资源投入等因素的影响,而且不同因素有着不同的重要性。运用区间Shapley值法对模糊合作对策的收益进行初步分配。通过将AHP-GEM法和模糊综合... 模糊合作对策的收益分配是个复杂问题,受到合作方的风险承担、合作努力、市场竞争、创新贡献和资源投入等因素的影响,而且不同因素有着不同的重要性。运用区间Shapley值法对模糊合作对策的收益进行初步分配。通过将AHP-GEM法和模糊综合评价法相结合,引入收益分配的综合修正因子,对区间Shapley值法进行改进,建立了模糊合作对策利益分配的改进模型。以制造业和物流业联盟为例,说明了改进模型的实用性和可行性。 展开更多
关键词 模糊合作对策 改进区间Shapley值 层次分析法和群组决策特征根法(AHP-GEM) 模糊综合评价法 收益分配 制造业与物流业联盟
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摩崖石刻中的唱和诗文研究
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作者 蔡文静 《宁波大学学报(人文科学版)》 2020年第2期36-43,共8页
石刻唱和诗不仅是文学作品的刊行与流传,也是诗文唱和活动的凝定,它融人、事、景、情于山岩石壁,是“诗可以观”“诗可以群”的典型。石刻唱和诗文多以诗摹景、以景解诗,形成诗景互观的模式;石刻唱和诗文常借景联结唱和,以诗和群,唱和相... 石刻唱和诗不仅是文学作品的刊行与流传,也是诗文唱和活动的凝定,它融人、事、景、情于山岩石壁,是“诗可以观”“诗可以群”的典型。石刻唱和诗文多以诗摹景、以景解诗,形成诗景互观的模式;石刻唱和诗文常借景联结唱和,以诗和群,唱和相勉;同时,将唱和刻之于石,使得“唱”与“和”相长相发,促进文学乃至文化的交流传承与生发。品评摩崖石刻中的唱和诗文,既能深刻体会诗中所咏所叹的景、人与文,也能感知文与景背后的石刻意趣与氛围。 展开更多
关键词 桂林 摩崖石刻 唱和诗 以诗和群
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NSGA-Ⅱ based traffic signal control optimization algorithm for over-saturated intersection group 被引量:5
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作者 李岩 过秀成 +1 位作者 陶思然 杨洁 《Journal of Southeast University(English Edition)》 EI CAS 2013年第2期211-216,共6页
In order to improve the efficiency of traffic signal control for an over-saturated intersection group, a nondominated sorting genetic algorithm Ⅱ(NSGA-Ⅱ) based traffic signal control optimization algorithm is prop... In order to improve the efficiency of traffic signal control for an over-saturated intersection group, a nondominated sorting genetic algorithm Ⅱ(NSGA-Ⅱ) based traffic signal control optimization algorithm is proposed. The throughput maximum and average queue ratio minimum for the critical route of the intersection group are selected as the optimization objectives of the traffic signal control for the over-saturated condition. The consequences of the efficiency between traffic signal timing plans generated by the proposed algorithm and a commonly utilized signal timing optimization software Synchro are compared in a VISSIM signal control application programming interfaces (SCAPI) simulation environment by using real filed observed traffic data. The simulation results indicate that the signal timing plan generated by the proposed algorithm is more efficient in managing oversaturated flows at intersection groups, and, thus, it has the capability of optimizing signal timing under the over-saturated conditions. 展开更多
关键词 traffic signal control optimization algorithm intersection group over-saturated status NSGA-H algorithm
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Polygynous Mating System and Behavioural Reason of Black Crested Gibbon (Nomascus concolor jingdongensis) at Dazhaizi,Mt.Wuliang, Yunnan,China 被引量:12
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作者 范朋飞 蒋学龙 +1 位作者 刘长铭 罗文寿 《Zoological Research》 CAS CSCD 北大核心 2006年第2期216-220,共5页
The field research on five black crested gibbon groups, recently performed at Dazhaizi, Mr. Wuliang, Central Yunnan, China, showed that all groups in the local population consisted of one adult male, two adult females... The field research on five black crested gibbon groups, recently performed at Dazhaizi, Mr. Wuliang, Central Yunnan, China, showed that all groups in the local population consisted of one adult male, two adult females and 2 - 5 sub-adults, juveniles and itfants. The mean group size was 6.2 in August 2003 and 6.4 in August 2005. Two subadult males disappeared from their natal home range and three newborns were given birth in Group 3 (G3) and G4 during this study. The two adult females in G1, G2 and G3 gave births and/or carried babies but at different times. There was no aggressive or dominating behaviour observed between the two adult females. One floating female was first seen in G3's territory on April 15, 2005. The two resident females interrupted her duet with adult male and chased her. We did not observe adult male chased this floating female and she left G3's territory 10 days later. Sub-adult males often kept distance with the family, and they often sang solo bouts in their natal territory before they dispersed. The sub-adult males and females dispersed from natal territory and two adult resident females rejected the third one, which might were the reasons why the black gibbon groups were polygyny in Dazhaizi. 展开更多
关键词 Nomascus concolor jingdongensis Group size and composition Social structure Polygyny Local population Wuliang Mountain
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Construction of new bornological quantum groups based on Galois objects
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作者 周楠 王栓宏 《Journal of Southeast University(English Edition)》 EI CAS 2016年第4期524-526,共3页
Let A be a bornological quantum group and R a bornological algebra. If R is an essential A-module, then there is a unique extension to M(A)-module with 1x = x. There is a one-to-one corresponding relationship betwee... Let A be a bornological quantum group and R a bornological algebra. If R is an essential A-module, then there is a unique extension to M(A)-module with 1x = x. There is a one-to-one corresponding relationship between the actions of A and the coactions of . If R is a Galois object for A, then there exists a faithful δ-invariant functional on R. Moreover,the Galois objects also have modular properties such as algebraic quantum groups. By constructing the comultiplication Δ,counit ε, antipode S and invariant functional φ onR×R, R×R can be considered as a bornological quantum group. 展开更多
关键词 bornological quantum groups actions and coactions Galois theory Galois objects
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Lie Point Symmetry Algebras and Finite Transformation Groups of Baroclinic Mode for Rotating Stratified Flows
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作者 元青青 楼森岳 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第5期878-882,共5页
The transformation groups and symmetries of the baroclinic mode for rotating stratified flow can be obtained via the standard approach. Applying the symmetry group on some special solutions, the newly obtained results... The transformation groups and symmetries of the baroclinic mode for rotating stratified flow can be obtained via the standard approach. Applying the symmetry group on some special solutions, the newly obtained results disprove a known conjecture. 展开更多
关键词 rotating stratified flows SYMMETRIES nonequivalent barotropic exact solutions
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A 9×9 Matrix Representation of Birman-Wenzl-Murakami Algebra and Berry Phase in Yang-Baxter System 被引量:2
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作者 苟立丹 薛康 王刚成 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第2期263-267,共5页
We present a 9×9 S-matrix and E-matrix.A representation of specialized Birman-Wenzl-Murakami algebra is obtained.Starting from the given braid group representation S-matrix,we obtain the trigonometric solution of... We present a 9×9 S-matrix and E-matrix.A representation of specialized Birman-Wenzl-Murakami algebra is obtained.Starting from the given braid group representation S-matrix,we obtain the trigonometric solution of Yang-Baxter equation.A unitary matrix R(x,φ1,φ2)is generated via the Yang-Baxterization approach.Then we construct a Yang-Baxter Hamiltonian through the unitary matrix R(x,φ1,φ2).Berry phase of this Yang-Baxter system is investigated in detail. 展开更多
关键词 Birman-Wenzl-Murakami algebra Yang Baxter equation Berry phase
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Changes in nitrogen and phosphorus and their effects on phytoplankton in the Bohai Sea 被引量:6
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作者 许思思 宋金明 +4 位作者 李学刚 袁华茂 李宁 段丽琴 孙培艳 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第4期945-952,共8页
Systematic studies of the changes in dissolved inorganic nitrogen(DIN) and dissolved inorganic phosphorus(DIP) and their effects on phytoplankton over the last 30 years in the Bohai Sea are presented.The amount of sew... Systematic studies of the changes in dissolved inorganic nitrogen(DIN) and dissolved inorganic phosphorus(DIP) and their effects on phytoplankton over the last 30 years in the Bohai Sea are presented.The amount of sewage disposal,use of fertilizer and the Huanghe River runoff were found to have a significant influence on the DIN or DIP concentrations in the Bohai Sea over the last 30 years.Moreover,the changes in DIN and DIP resulted in changes in the limiting nutrients of phytoplankton in the Bohai Sea from nitrogen in the early 1980s to nitrogen-phosphorus in the late 1980s,and then to phosphorus after the 1990s.In addition,changes in nitrogen and phosphorus had a significant effect on the phytoplankton community structure.The half saturation constant(Ks) was used to evaluate the effect of nutrients on the phytoplankton community structure in the Bohai Sea over the last 30 years.Cell abundance percentages of dominant phytoplankton species with high Ks values for phosphorus and low Ks values for nitrogen have decreased since the 1980s,while those of dominant phytoplankton species with low Ks values for phosphorus and high Ks values for nitrogen increased during this period. 展开更多
关键词 dissolved inorganic nitrogen and phosphorus CHLOROPHYLL-A phytoplankton community Bohai Sea
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Decadal Variation of the Aleutian Low-Icelandic Low Seesaw Simulated by a Climate System Model(CAS-ESM-C) 被引量:6
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作者 DONG Xiao SU Tong-Hua +1 位作者 WANG Jun LIN Ren-Ping 《Atmospheric and Oceanic Science Letters》 CSCD 2014年第2期110-114,共5页
Based on a simulation using a newly developed climate system model(Chinese Academy of Sciences-Earth System Model-Climate system component, CAS-ESM-C), the author investigated the Aleutian Low- Icelandic Low Seesaw(AI... Based on a simulation using a newly developed climate system model(Chinese Academy of Sciences-Earth System Model-Climate system component, CAS-ESM-C), the author investigated the Aleutian Low- Icelandic Low Seesaw(AIS) and its decadal variation. Results showed that the CAS-ESM-C can reasonably reproduce not only the spatial distribution of the climatology of sea level pressure(SLP) in winter, but also the AIS and its decadal variation. The period 496–535 of the integration by this model was divided into two sub-periods: 496–515(P1) and 516–535(P2) to further investigate the decadal weakening of the AIS. It was shown that this decadal variation of the AIS is mainly due to the phase transition of the Pacific Decadal Oscillation(PDO), from its positive phase to its negative phase. This transition of the PDO causes the sea surface temperature(SST) in the equatorial eastern(northern) Pacific to cool(warm), resulting in the decadal weakening of mid-latitude westerlies over the North Pacific and North Atlantic. This may be responsible for the weakening of the inverse relation between the Aleutian Low(AL) and the Icelandic Low(IL). 展开更多
关键词 CAS-ESM-C Aleutian Low Icelandic Low Pacific Decadal Oscillation
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Effects of a patchy seagrass meadow on the macrobenthic community
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作者 MENG Zhou YAN Runxuan HAN Qingxi 《Marine Science Bulletin》 2022年第1期72-88,共17页
Based on macrobenthos collected from intertidal seagrass bed in Guangrao,Shandong Province in May 2013,the macrobenthic structure and diversity were analyzed.A total of 41 macrobenthic species were identified,among wh... Based on macrobenthos collected from intertidal seagrass bed in Guangrao,Shandong Province in May 2013,the macrobenthic structure and diversity were analyzed.A total of 41 macrobenthic species were identified,among which crustaceans were the most speciose macrobenthic taxa(16 species),followed by polychaetes(15 species)and mollusks(10 species).Seven dominant macrobenthic species were identified,including 3 species of polychaetes,2 species of crustaceans and 2 species of mollusks.The total abundance across the whole sampling area was 661.33 ind/m2.Total abundance and the abundance of Potamocorbula laevis and Heteromastus filiformis showed significant spatial variation,and the macrobenthic abundance distributed in seagrass meadows was higher than that in other areas.The results of cluster,nMDS ordination,SIMPER and IMS analyses all showed no linear correlation along the distance gradient from the seagrass meadow.Therefore,degraded seagrass can still provide detectable but limited ecological services.However,the rehabilitation of seagrass bed is essential and urgent to regain their full ecological function. 展开更多
关键词 Guangrao SHANDONG seagrass bed MACROBENTHOS community composition and structure
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Genetic Differences between Wild and Captive Populations of the Peregrine Falcon (Falco peregrinus) and the Saker Falcon (Falco cherrug) Living in the Czech Republic
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作者 Bryndova Marta Putnova Lenka Bartonova Petra Kaplanova Katerina Urban Tomas 《Journal of Agricultural Science and Technology(B)》 2012年第6期642-651,共10页
The microsatellite analysis of DNA plays an important role in studying the population genetics such as population structure, genetic variability and diversity, phylogenetic relationships of wild population of endanger... The microsatellite analysis of DNA plays an important role in studying the population genetics such as population structure, genetic variability and diversity, phylogenetic relationships of wild population of endangered species. The main aim of this study was the estimation of ten microsatellite markers variability in the F. cherrug and F. peregrinus populations. We investigated genetic diversity and structure of populations by using non-invasive genetic identification of individuals to characterize populations of raptors living in the captivity and wild in the Czech Republic during the breeding seasons 2009 and 2010. Within Falco cherrug, significant moderate genetic differentiation (FsT) was observed between Falco cherrug wild and captive. This means that there could be a little differentiation between the wild and the captive populations caused by Falco cherrug subspecies origin or hybridization in the captivity. The absence of significant genetic differentiation between Falco peregrinus wild and captive may be caused by the influence of reintroduction the captive populations in the past. Whereas one breeding population ofFalco peregrinus (Kokorinsko2 2010) was clustered by UPGMA dendrogram into the individual group, we assumed this population like independent, maybe not influenced by other groups. Moreover, a larger sample size would be necessary to confirm the hypothesis. 展开更多
关键词 RAPTORS microsatellites population structure genetic variability peregrine falcon (Falco peregrinus) saker falcon Falco cherrug).
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Incidence and Development of Powdery Mildew (Blumeria graminis f.sp. tritici) in the Czech Republic in the Years 1999-2010 and Race Spectrum of This Population 被引量:1
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作者 Lubomir Vechet 《Journal of Life Sciences》 2012年第7期786-793,共8页
Powdery mildew (Blumeria graminis f.sp. tritici) is one of the most important leaf diseases of wheat on the worldwide. Evolutionary potential of a pathogen population is reflected in its population genetic structure... Powdery mildew (Blumeria graminis f.sp. tritici) is one of the most important leaf diseases of wheat on the worldwide. Evolutionary potential of a pathogen population is reflected in its population genetic structure. Severity of powdery mildew in twelve years of small-plot experiments was in individual years different. Incidence of powdery mildew was followed in 1999-2010 and powdery mildew development was studied in 2003 and 2004 in the Crop Research Institute (CRI). These experiments were made on the cultivar Kanzler, susceptible cultivar to powdery mildew. Disease severity was made as a percentage of typical symptoms of the disease. Structure of powdery mildew population was probed in 2009 and 2010 in CRI and in the locality Humpolec. The highest was in 2004 and the lowest in 2003. Development of the disease in two extreme years depended on progress of weather factors mainly to average daily temperature and photosynthetic active radiation. In the year 2009 was higher disease severity in CRI than in the CRI station in Humpolec but in 2010 vice versa higher disease severity was in Humpolec. Observation showed that in small distances of two localities can be differences in composition of powdery mildew population. Higher virulence in CRI was to the gene of specific resistance Pml whereas in Humpolec to the gene Pm 17. In the year 2010 in CRI was the highest virulence to the gene Pm 1 whereas in Humpolec the highest virulence was to the genes Pm3fand Pm4a. Differences of powdery mildew were in 12 years of observation were very distinct and showed difference in structure of powdery mildew population in near localities. 展开更多
关键词 Powdery mildew INCIDENCE DEVELOPMENT VIRULENCE race spectrum.
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An Intelligent Early Warning Method of Press-Assembly Quality Based on Outlier Data Detection and Linear Regression
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作者 XUE Shanliang LI Chen 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2020年第4期597-606,共10页
Focusing on controlling the press-assembly quality of high-precision servo mechanism,an intelligent early warning method based on outlier data detection and linear regression is proposed.Linear regression is used to d... Focusing on controlling the press-assembly quality of high-precision servo mechanism,an intelligent early warning method based on outlier data detection and linear regression is proposed.Linear regression is used to deal with the relationship between assembly quality and press-assembly process,then the mathematical model of displacement-force in press-assembly process is established and a qualified press-assembly force range is defined for assembly quality control.To preprocess the raw dataset of displacement-force in the press-assembly process,an improved local outlier factor based on area density and P weight(LAOPW)is designed to eliminate the outliers which will result in inaccuracy of the mathematical model.A weighted distance based on information entropy is used to measure distance,and the reachable distance is replaced with P weight.Experiments show that the detection efficiency of the algorithm is improved by 5.6 ms compared with the traditional local outlier factor(LOF)algorithm,and the detection accuracy is improved by about 2%compared with the local outlier factor based on area density(LAOF)algorithm.The application of LAOPW algorithm and the linear regression model shows that it can effectively carry out intelligent early warning of press-assembly quality of high precision servo mechanism. 展开更多
关键词 quality early warning outlier data detection linear regression local outlier factor based on area density and P weight(LAOPW) information entropy P weight
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Self-organizing dual clustering considering spatial analysis and hybrid distance measures 被引量:10
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作者 JIAO LiMin LIU YaoLin ZOU Bin 《Science China Earth Sciences》 SCIE EI CAS 2011年第8期1268-1278,共11页
Dual clustering performs object clustering in both spatial and non-spatial domains that cannot be dealt with well by traditional clustering methods.However,recent dual clustering research has often omitted spatial out... Dual clustering performs object clustering in both spatial and non-spatial domains that cannot be dealt with well by traditional clustering methods.However,recent dual clustering research has often omitted spatial outliers,subjectively determined the weights of hybrid distance measures,and produced diverse clustering results.In this study,we first redefined the dual clustering problem and related concepts to highlight the clustering criteria.We then presented a self-organizing dual clustering algorithm (SDC) based on the self-organizing feature map and certain spatial analysis operations,including the Voronoi diagram and polygon aggregation and amalgamation.The algorithm employs a hybrid distance measure that combines geometric distance and non-spatial similarity,while the clustering spectrum analysis helps to determine the weight of non-spatial similarity in the measure.A case study was conducted on a spatial database of urban land price samples in Wuhan,China.SDC detected spatial outliers and clustered the points into spatially connective and attributively homogenous sub-groups.In particular,SDC revealed zonal areas that describe the actual distribution of land prices but were not demonstrated by other methods.SDC reduced the subjectivity in dual clustering. 展开更多
关键词 dual clustering DATAMINING self-organizing feature map Voronoi diagram
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ON HARMONIC MAPS INTO SYMPLECTIC GROUPS Sp(N) 被引量:5
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作者 HEQUN SHENYIBING 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2001年第4期519-528,共10页
By means of the theory of harmonic maps into the unitary group U(N), the authors study harmonic maps into the symplectic group Sp(N). The symplectic uniton and symplectic ex--tended uniton are introduced. The method o... By means of the theory of harmonic maps into the unitary group U(N), the authors study harmonic maps into the symplectic group Sp(N). The symplectic uniton and symplectic ex--tended uniton are introduced. The method of the symplectic Backlund transformation and the Darboux transformation is used to construct new symplectic unitons from a known one. 展开更多
关键词 Harmonic map Symplectic group Symplectic uniton Darboux transformation
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Temporal changes in soil bacterial and archaeal communities with different fertilizers in tea orchards 被引量:5
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作者 Hua WANG Shao-hui YANG +3 位作者 Jing-ping YANG Ya-min LV Xing ZHAO Ji-liang PANG 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2014年第11期953-965,共13页
It is important to understand the effects of temporal changes in microbial communities in the acidic soils of tea orchards with different fertilizers. A field experiment involving organic fertilizer (OF), chemical f... It is important to understand the effects of temporal changes in microbial communities in the acidic soils of tea orchards with different fertilizers. A field experiment involving organic fertilizer (OF), chemical fertilizer (CF), and unfertilized control (CK) treatments was arranged to analyze the temporal changes in the bacterial and archaeal communities at bimonthly intervals based on the 16S ribosomal RNA (rRNA) gene using terminal restriction fragment length polymorphism (T-RFLP) profiling. The abundances of total bacteria, total archaea, and selected functional genes (bacterial and archaeal amoA, bacterial narG, nirK, nirS, and nosZ) were determined by quantitative poly- merase chain reaction (qPCR). The results indicate that the structures of bacterial and archaeal communities varied significantly with time and fertilization based on changes in the relative abundance of dominant T-RFs. The abundancy of the detected genes changed with time. The total bacteria, total archaea, and archaeal amoA were less abundant in July. The bacterial amoA and denitrifying genes were less abundant in September, except the nirK gene. The OF treatment increased the abundance of the observed genes, while the CF treatment had little influence on them. The soil temperature significantly affected the bacterial and archaeal community structures. The soil moisture was signif- icantly correlated with the abundance of denitrifying genes. Of the soil chemical properties, soil organic carbon was the most important factor and was significantly correlated with the abundance of the detected genes, except the nirK gene. Overall, this study demonstrated the effects of both temporal alteration and organic fertilizer on the structures of mi- crobial communities and the abundance of genes involved in the nitrogen cycle. 展开更多
关键词 Bacterial and archaeal communities FERTILIZER Soil Temporal changes Tea orchard Functional genes
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