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Spatiotemporal dynamics of the social structure of Indo-Pacific humpback dolphins(Sousa chinensis)in Xiamen waters from 2007 to 2019
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作者 Yi Lu Xin-Rong Xu +3 位作者 Bing-Yao Chen Thomas A Jefferson Holly Fearnbach Guang Yang 《Zoological Research》 SCIE CSCD 2024年第2期439-450,共12页
As highly social animals,Indo-Pacific humpback dolphins(Sousa chinensis)exhibit community differentiation.Nevertheless,our understanding of the external and internal factors influencing these dynamics,as well as their... As highly social animals,Indo-Pacific humpback dolphins(Sousa chinensis)exhibit community differentiation.Nevertheless,our understanding of the external and internal factors influencing these dynamics,as well as their spatiotemporal variations,is still limited.In the present study,variations in the social structure of an endangered Indo-Pacific humpback dolphin population in Xiamen Bay,China,were monitored over two distinct periods(2007–2010 and 2017–2019)to analyze the effects of habitat utilization and the composition of individuals within the population.In both periods,the population demonstrated a strikingly similar pattern of social differentiation,characterized by the division of individuals into two main clusters and one small cluster.Spatially,the two primary clusters occupied the eastern and western waters,respectively,although the core distribution area of the eastern cluster shifted further eastward between the two periods.Despite this distribution shift,the temporal stability of the social structure and inter-associations within the eastern cluster remained unaffected.A subset of 16individuals observed in both periods,comprising 51.6%and 43.2%of the population in each respective period,emerged as a foundational element of the social structure and may be responsible for sustaining social structure stability,especially during the 2007–2010 period.These observations suggest that the composition of dominant individuals,an internal factor,had a more substantial influence on the formation of the social network than changes in habitat use,an external factor.Consequently,the study proposes distinct conservation measures tailored to each of the two main clusters. 展开更多
关键词 social differentiation social structure Sousa chinensis DYNAMICS CONSERVATION
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Integrating Neighborhood Geographic Distribution and Social Structure Influence for Social Media User Geolocation
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作者 Meng Zhang Xiangyang Luo Ningbo Huang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第9期2513-2532,共20页
Geolocating social media users aims to discover the real geographical locations of users from their publicly available data,which can support online location-based applications such as disaster alerts and local conten... Geolocating social media users aims to discover the real geographical locations of users from their publicly available data,which can support online location-based applications such as disaster alerts and local content recommen-dations.Social relationship-based methods represent a classical approach for geolocating social media.However,geographically proximate relationships are sparse and challenging to discern within social networks,thereby affecting the accuracy of user geolocation.To address this challenge,we propose user geolocation methods that integrate neighborhood geographical distribution and social structure influence(NGSI)to improve geolocation accuracy.Firstly,we propose a method for evaluating the homophily of locations based on the k-order neighbor-hood geographic distribution(k-NGD)similarity among users.There are notable differences in the distribution of k-NGD similarity between location-proximate and non-location-proximate users.Exploiting this distinction,we filter out non-location-proximate social relationships to enhance location homophily in the social network.To better utilize the location-proximate relationships in social networks,we propose a graph neural network algorithm based on the social structure influence.The algorithm enables us to perform a weighted aggregation of the information of users’multi-hop neighborhood,thereby mitigating the over-smoothing problem of user features and improving user geolocation performance.Experimental results on real social media dataset demonstrate that the neighborhood geographical distribution similarity metric can effectively filter out non-location-proximate social relationships.Moreover,compared with 7 existing social relationship-based user positioning methods,our proposed method can achieve multi-granularity user geolocation and improve the accuracy by 4.84%to 13.28%. 展开更多
关键词 User geolocation social media neighborhood geographic distribution structure influence
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Tuning Structural and Electronic Configuration of FeN_(4) via External S for Enhanced Oxygen Reduction Reaction
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作者 Shidong Li Lixue Xia +9 位作者 Jiantao Li Zhuo Chen Wei Zhang Jiexin Zhu Ruohan Yu Fang Liu Sungsik Lee Yan Zhao Liang Zhou Liqiang Mai 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第2期93-101,共9页
The Fe-N-C material represents an attractive oxygen reduction reaction electrocatalyst,and the FeN_(4)moiety has been identified as a very competitive catalytic active site.Fine tuning of the coordination structure of... The Fe-N-C material represents an attractive oxygen reduction reaction electrocatalyst,and the FeN_(4)moiety has been identified as a very competitive catalytic active site.Fine tuning of the coordination structure of FeN_(4)has an essential impact on the catalytic performance.Herein,we construct a sulfur-modified Fe-N-C catalyst with controllable local coordination environment,where the Fe is coordinated with four in-plane N and an axial external S.The external S atom affects not only the electron distribution but also the spin state of Fe in the FeN_(4)active site.The appearance of higher valence states and spin states for Fe demonstrates the increase in unpaired electrons.With the above characteristics,the adsorption and desorption of the reactants at FeN_(4)active sites are optimized,thus promoting the oxygen reduction reaction activity.This work explores the key point in electronic configuration and coordination environment tuning of FeN_(4)through S doping and provides new insight into the construction of M-N-C-based oxygen reduction reaction catalysts. 展开更多
关键词 coordination structure electronic configuration FeN_(4)moiety oxygen reduction reaction sulfur doping
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Analysis of Urban Agglomeration Network Structure Based on Baidu Migration Data: A Case Study of the Guangdong-Hong Kong-Macao Greater Bay Urban Agglomeration
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作者 XIA Yuan WANG Bin 《Journal of Landscape Research》 2024年第4期47-50,共4页
The inter-city linkage heat data provided by Baidu Migration is employed as a characterization of inter-city linkages in order to facilitate the study of the network linkage characteristics and hierarchical structure ... The inter-city linkage heat data provided by Baidu Migration is employed as a characterization of inter-city linkages in order to facilitate the study of the network linkage characteristics and hierarchical structure of urban agglomeration in the Greater Bay Area through the use of social network analysis method.This is the inaugural application of big data based on location services in the study of urban agglomeration network structure,which represents a novel research perspective on this topic.The study reveals that the density of network linkages in the Greater Bay Area urban agglomeration has reached 100%,indicating a mature network-like spatial structure.This structure has given rise to three distinct communities:Shenzhen-Dongguan-Huizhou,Guangzhou-Foshan-Zhaoqing,and Zhuhai-Zhongshan-Jiangmen.Additionally,cities within the Greater Bay Area urban agglomeration play different roles,suggesting that varying development strategies may be necessary to achieve staggered development.The study demonstrates that large datasets represented by LBS can offer novel insights and methodologies for the examination of urban agglomeration network structures,contingent on the appropriate mining and processing of the data. 展开更多
关键词 Baidu migration data social network analysis Urban agglomeration network structure Greater Bay Area urban agglomeration
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Synthesis and Structure of anti-Configuration Complex [Cu(tssb)_2]·2[(H_3O)Cl]·4H_2O 被引量:4
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作者 张淑华 蒋毅民 +1 位作者 刘峥 周忠远 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2004年第8期882-885,共4页
The title complex [Cu(tssb)2]2[(H3O)Cl]4H2O (C18H34Cl2CuN2O14S2) (tssb = tau- rine salicylaldehyde Schiff base) has been synthesized by the reaction of taurine salicylaldehyde Schiff base (tssb) and copper acetate in ... The title complex [Cu(tssb)2]2[(H3O)Cl]4H2O (C18H34Cl2CuN2O14S2) (tssb = tau- rine salicylaldehyde Schiff base) has been synthesized by the reaction of taurine salicylaldehyde Schiff base (tssb) and copper acetate in water-ethanol. Its single-crystal structure was determined by X-ray diffraction method. The crystal structure belongs to triclinic, space group P1 with a = 0.7407(1), b = 1.3329(3), c = 1.5736(3) nm, ?= 103.800(4), ?= 95.030(4), ?= 104.416(4)? Mr = 701.06, V = 1.4433(5) nm3, Z = 2, Dc = 1.613 g/cm3, = 1.153 mm-1 and F(000) = 726. The compound is an infinitely expanding three-dimensional network connected with hydrogen bonds. The Cu(Ⅱ) atom is coordinated by two nitrogen and two oxygen atoms to form a distorted planar coordination compound which adopts anti-configuration because two sulfonic acid groups are posi- tioned diagonally on a plane. 展开更多
关键词 copper complex taurine-salicylaldehyde Schiff base crystal structure anti- configuration
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Research on Web-Based Product Structure and Configuration Management 被引量:1
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作者 CHENJi-zhong TIANLing XUXiao-hui 《Computer Aided Drafting,Design and Manufacturing》 2004年第2期27-33,共7页
An enhanced system architecture of Web-based product structure and configuration management system along with its, functions are is presented. The key techniques, such as construction of object models of product str... An enhanced system architecture of Web-based product structure and configuration management system along with its, functions are is presented. The key techniques, such as construction of object models of product structure and product configuration, hybrid approach method in product configuration management, sharing and integration of heterogeneous product data, integration with other sub-systems, are discussed too. A prototype system is developed by J2EE technology. 展开更多
关键词 product structure and configuration management hybrid configuration method data sharing
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X-ray absorption near-edge structure study on the configuration of Cu2+/histidine complexes at different pH values
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作者 于梅娟 王宇 徐伟 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第4期474-478,共5页
The local configurations around metal ions in metalloproteins are of great significance for understanding their biolog- ical functions. Cu2+/histidine (His) is a typical complex existing in many metalloproteins and... The local configurations around metal ions in metalloproteins are of great significance for understanding their biolog- ical functions. Cu2+/histidine (His) is a typical complex existing in many metalloproteins and plays an important role in lots of physiological functions. The three-dimensional (3D) structural configurations of Cu2+/His complexes at different pH values (2.5, 6.5, and 8.5) are quantitatively determined by x-ray absorption near-edge structure (XANES). Generally Cu2+/His complex keeps an octahedral configuration consisting of oxygen atoms from water molecules and oxygen or nitrogen atoms from histidine molecules coordinated around Cu2+. It is proved in this work that the oxygen atoms from water molecules, when increasing the pH value from acid to basic value, are gradually substituted by the Ocarboxy1, Nam, and Nim from hisitidine molecules. Furthermore, the symmetries of Cu2+/His complexes at pH 6.5 and pH 8.5 are found to be lower than at pH 2.5. 展开更多
关键词 x-ray absorption near-edge structure Cu2+/His pH values configuration
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Synthesis, Crystal Structure and Absolute Configuration of (+)-O-Phenyl Cyclophosphorodiamidate
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作者 何可 周正洪 +3 位作者 李康应 赵国锋 唐除痴 王宏根 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2003年第6期705-709,共5页
The title compound, (+)-O-phenyl cyclophosphorodiamidate (C28H33N2O2P, Mr = 460.53), has been synthesized and characterized by 31P NMR, 1H NMR and elemental analysis. X-ray diffraction analysis at 273(2) K indicates t... The title compound, (+)-O-phenyl cyclophosphorodiamidate (C28H33N2O2P, Mr = 460.53), has been synthesized and characterized by 31P NMR, 1H NMR and elemental analysis. X-ray diffraction analysis at 273(2) K indicates that it belongs to orthorhombic system, space group P212121 with a = 11.518(4), b = 13.449(4), c = 16.539(5) ? V = 2562(1) 3, Z = 4, Dc = 1.194 g/cm3, F(000) = 984 and m(MoKa) = 0.134 mm-1. The structure parameters were refined by full-matrix least-squares on F2 to R = 0.0459 and wR = 0.0640. The flack x parameter is 0.03(10), and the absolute configuration of the phosphorus atom in the title compound is S. 展开更多
关键词 O-phenyl cyclophosphorodiamidate crystal structure absolute configuration
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Synthesis,Crystal Structure and Absolute Configuration of (+)-(a-Hydroxybenzyl)phenylphosphinic acid
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作者 蔡觉晓 周正洪 +1 位作者 唐除痴 王宏根 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2002年第4期368-370,共3页
The title compound (+)-(a-hydroxybenzyl)phenylphosphinic acid (C13H13O3P, Mr = 248.20) has been synthesized and characterized by 31P NMR, 1H NMR and elemental analysis. X-ray diffraction analysis at 293(2) K indicates... The title compound (+)-(a-hydroxybenzyl)phenylphosphinic acid (C13H13O3P, Mr = 248.20) has been synthesized and characterized by 31P NMR, 1H NMR and elemental analysis. X-ray diffraction analysis at 293(2) K indicates that the compound belongs to monoclinic system, space group C2 with cell parameters: a = 23.560(8), b = 6.947(2), c = 7.854(3) ? b = 91.273(6)? V = 1285.2(7) 3, Z = 4, Dc = 1.283 g/cm3, F(000) = 520 and m(MoKa) = 0.207 mm-1. The number of independent reflections amounts to 1991, of which 1507 are observed reflections. The crystal structure has been determined by direct methods (SHELXL-97). The structure parameters are refined by full-matrix least-squares on F2 to R = 0.0437 and wR = 0.0893. The flack x parameter is 0.0001. The absolute configuration of the a-carbon in the title compound is S. 展开更多
关键词 a-hydroxyphosphinic acid (+)-(a-hydroxybenzyl)phenylphosphinic acid crystal structure absolute configuration
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Reconfigurable Modeling Technology of Similar-structure Products Configuration Design
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作者 QIU Lemiao REN Bin +1 位作者 ZHANG Shuyou XU Jian 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2013年第1期189-196,共8页
The product configuration modeling is a key technology to realize configuration design. Most of the researches were mainly conducted focusing on how to establish a product configuration model, but were short of the co... The product configuration modeling is a key technology to realize configuration design. Most of the researches were mainly conducted focusing on how to establish a product configuration model, but were short of the consideration about the application scope and dynamic change features. In this paper, the reconfigurable modeling technology of similar-structure products configuration design is studied to enhance the generality and diversity of product configuration models, and to facilitate the dynamic upgrade of configuration models. The configuration components of products with similar structures are divided into sharable configuration components, essential configuration components and optional configuration components, so the construction of reconfigurable model of configuration design can be converted into the set operation of configuration components. The horizontal adjusting reconstruction of configuration model is carried out through the adding, replacing and deleting of configuration components, the vertical adjusting reconstruction of configuration model is carried out through the parametric deformation of configuration components, and the variable topological configuration model reconstruction can be realized through the transformation of partial structure of configuration components. Finally, NC machine products are used as an example to analyze and verify the reconfigurable modeling technology of products with similar structures. The speed of NC machine configuration design is found to be improved, and the number of NC machine configuration design models is decreased. And the reconfigurable design system of NC machine products is developed. The proposed modeling technology provides references for the processes, methods and steps of model reconstruction. 展开更多
关键词 similar-structure products configuration component product configuration model RECONSTRUCTION
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Correlation effects on the fine-structure splitting within the 3d9 ground configuration in highly-charged Co-like ions
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作者 郭学玲 黄敏 +4 位作者 颜君 李双 王凯 司然 陈重阳 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第1期535-542,共8页
A comprehensive theoretical study of correlation effects on the fine-structure splitting within the ground configuration 3d9 of the Co-like HI45+, Ta46+, W47+, and Au52+ ions is performed by employing the multi-co... A comprehensive theoretical study of correlation effects on the fine-structure splitting within the ground configuration 3d9 of the Co-like HI45+, Ta46+, W47+, and Au52+ ions is performed by employing the multi-configuration Dirac-Hartree- Fock method in the active space approximation. It shows that the core-valence correlation with the inner-core 2p electron is more significant than with the outer 3p and 3s electrons, and the correlation with the 2s electron is also noticeable. The core-core correlation seems to be small and can be ignored. The calculated 2D3/2,5/2 splitting energies agree with the recent electron-beam ion-trap measurements [Phys. Rev. A 83 032517 (2011), Eur. Phys. J. D 66 286 (2012)] to within the experimental uncertainties. 展开更多
关键词 correlation effects multi-configuration Dirac-Hartree-Fock method high-Z Co-like ions fine- structure splitting
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Input Structure Design for Structural Controllability of Complex Networks 被引量:1
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作者 Lifu Wang Zhaofei Li +2 位作者 Guotao Zhao Ge Guo Zhi Kong 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第7期1571-1581,共11页
This paper addresses the problem of the input design of large-scale complex networks.Two types of network components,redundant inaccessible strongly connected component(RISCC)and intermittent inaccessible strongly con... This paper addresses the problem of the input design of large-scale complex networks.Two types of network components,redundant inaccessible strongly connected component(RISCC)and intermittent inaccessible strongly connected component(IISCC)are defined,and a subnetwork called a driver network is developed.Based on these,an efficient method is proposed to find the minimum number of controlled nodes to achieve structural complete controllability of a network,in the case that each input can act on multiple state nodes.The range of the number of input nodes to achieve minimal control,and the configuration method(the connection between the input nodes and the controlled nodes)are presented.All possible input solutions can be obtained by this method.Moreover,we give an example and some experiments on real-world networks to illustrate the effectiveness of the method. 展开更多
关键词 Complex network input configuration minimum controlled node set structural controllability
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Empirical analysis of carbon tariff's effect on the export structure of China's manufacturing industry and social welfare based on the GTAP model 被引量:3
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作者 Yan Li Mengmeng Wang +1 位作者 Yi Sui Qingbo Huang 《Chinese Journal of Population,Resources and Environment》 2016年第1期1-10,共10页
In recent years,carbon emissions have gradually evolved from an environment issue into a political and economic one.Carbon tariff has brought about new trade barriers of developed countries,and in order to enhance the... In recent years,carbon emissions have gradually evolved from an environment issue into a political and economic one.Carbon tariff has brought about new trade barriers of developed countries,and in order to enhance the industrial competitiveness of developed countries,it will produce unfavorable impact on developing countries.Concentrated on the manufacturing industry,which is the most intensive high-carbon industry in China's export structure,this article studies the relationship between carbon tariff policy and industry structure of export trade and builds up a relation between climate change and international trade.First,by means of establishing a partial equilibrium model,it applies geometric analysis and mathematical analysis to compute the impact on China's manufacturing export trade and the consequences of the introduction of the US carbon tariff to China's manufacturing industry that has already imposed a domestic shipping carbon tax.Furthermore,with the application of the GTAP model,it estimates the overall economic and welfare effects on China's manufacturing industry if the US and Europe introduce carbon tariff by means of four ways,and then analyzes the influence on China's manufacturing industry export structure and social welfare as well.The result shows that the introduction of the US carbon import tariff lowers China's export price and export volume,and the implementation of a domestic carbon tax justifies a higher export price and a lower export volume for China.However,the degree of export reduction is smaller than that under the effect of the US carbon tariff.In the case of developed countries imposing carbon tariff on China's energy-intensive industries,such as chemical rubber products,oil and coal-processing industry and paper industry,whose export would be reduced,the negative impact on the paper industry is the severest,which will decrease the paper industry's export ranging from 1.79%to 6.05%,whereas the other industries' export will increase.Anyhow,it will promote China's manufacturing industry to adjust the export structure to a certain extent.In addition,it will lead to a decrease in China's welfare,with a decrease between $2,134 billion and $8,347 billion.Finally,this paper provides information on international coordination,export structure adjustment and green manufacturing adjustment as a reference for the development of China's manufacturing industry. 展开更多
关键词 carbon tariff manufacturing industry export structure social welfare GTAP model
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Diverse atomic structure configurations of metal-doped transition metal dichalcogenides for enhancing hydrogen evolution 被引量:1
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作者 Longlu Wang Yuxin Zhang +3 位作者 Chen Gu Haoxuan Yu Yanling Zhuang Zechao Zhuang 《Nano Research》 SCIE EI CSCD 2024年第5期3586-3602,共17页
Doping foreign metal atoms into the substrate of transition metal dichalcogenides(TMDs)enables the formation of diverse atomic structure configurations,including isolated atoms,chains,and clusters.Therefore,it is very... Doping foreign metal atoms into the substrate of transition metal dichalcogenides(TMDs)enables the formation of diverse atomic structure configurations,including isolated atoms,chains,and clusters.Therefore,it is very important to reasonably control the atomic structure and determine the structure-activity relationship between the atomic configurations and the hydrogen evolution reaction(HER)performance.Although numerous studies have indicated that doping can yield diverse atomic structure configurations,there remains an incomplete understanding of the relationship between atomic configurations within the lattice of TMDs and their performance.Here,diverse atomic structure configurations of adsorptive doping,substitutional doping,and TMDs alloys are summarized.The structure-activity relationship between different atomic configurations and HER performance can be determined by micro-nanostructure devices and density functional theory(DFT)calculations.These diverse atomic structure configurations are of great significance for activating the inert basal plane of TMDs and improving the catalytic activity of HER.Finally,we have summarized the current challenges and future opportunities,offering new perspectives for the design of highly active and stable metal-doped TMDs catalysts. 展开更多
关键词 transition metal dichalcogenides(TMDs) dopant effect diverse atomic structure configurations hydrogen evolution reaction(HER)
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Configuration Synthesis and Lightweight Networking of Deployable Mechanism Based on a Novel Pyramid Module
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作者 Jinwei Guo Jianliang He +2 位作者 Guoxing Zhang Yongsheng Zhao Yundou Xu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第4期294-310,共17页
Deployable mechanism with preferable deployable performance,strong expansibility,and lightweight has attracted much attention because of their potential in aerospace.A basic deployable pyramid unit with good deployabi... Deployable mechanism with preferable deployable performance,strong expansibility,and lightweight has attracted much attention because of their potential in aerospace.A basic deployable pyramid unit with good deployability and expandability is proposed to construct a sizeable deployable mechanism.Firstly,the basic unit folding principle and expansion method is proposed.The configuration synthesis method of adding constraint chains of spatial closed-loop mechanism is used to synthesize the basic unit.Then,the degree of freedom of the basic unit is analyzed using the screw theory and the link dismantling method.Next,the three-dimensional models of the pyramid unit,expansion unit,and array unit are established,and the folding motion simulation analysis is carried out.Based on the number of components,weight reduction rate,and deployable rate,the performance characteristics of the three types of mechanisms are described in detail.Finally,prototypes of the pyramid unit,combination unit,and expansion unit are developed to verify further the correctness of the configuration synthesis based on the pyramid.The proposed deployable mechanism provides aference for the design and application of antennas with a large aperture,high deployable rate,and lightweight.It has a good application prospect in the aerospace field. 展开更多
关键词 Pyramid unit Deployable mechanism configuration synthesis structural design Lightweight networking
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Structured Equation Model of Tuberculosis Incidence Based on Its Social Determinants and Risk Factors in Bandar Lampung, Indonesia 被引量:1
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作者 Dyah Wulan Sumekar Rengganis Wardani Lutfan Lazuardi +1 位作者 Yodi Mahendradhata Hari Kusnanto 《Open Journal of Epidemiology》 2014年第2期76-83,共8页
World Health Organization through tuberculosis (TB) control averted up to six million deaths and cured thirty-six million people in 1995-2008, but had less success in reducing TB incidence, especially in thirteen high... World Health Organization through tuberculosis (TB) control averted up to six million deaths and cured thirty-six million people in 1995-2008, but had less success in reducing TB incidence, especially in thirteen high burden countries, including Indonesia. Therefore, TB control will need to have more emphasis on the issues of social determinants, as social determinants affect TB’s incidence directly and/-or through TB’s risk factors. This study aimed to identify a significant effect of social determinants and the risk factors of TB incidence. The research setting was at twenty-seven primary health centers and one hospital that have implemented the Directly Observed Treatment Short Course (DOTS) strategy in Bandar Lampung municipality, Indonesia. Respondents of this research were 238 smear-positive TB patients as case group and 238 patients without TB as control group. Research variables consisted of “social determinants”, “housing condition”, “household food security” and “health access” which were set as latent variables and measured through their indicators. Data had been collected by using questionnaire and then was analyzed with Structural Equation Modeling using SmartPLS 2.0 software. The result showed that “social determinants” through “housing condition” and “household food security” affected “TB incidence”. Moreover, “social determinants”, “housing condition” and “household food security” can be used to explain 34.1% variation of “TB incidence”. In conclusion, the knowledge can be used to support the TB control program, particularly to implement the DOTS strategy together with improving social determinants, housing condition and household food security. 展开更多
关键词 social Determinants HOUSING Condition HOUSEHOLD Food Security TB INCIDENCE structural Equation Modeling
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An Empirical Study of Urban Spatial Structure Based on Social Network Analys is: A Case Study of Urban Update Unit in Shenzhen as an Example 被引量:1
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作者 LIN Yuxuan SI Nan 《Journal of Landscape Research》 2020年第2期32-36,共5页
Through sorting out the data of urban renewal units in Shenzhen from 2010 to 2016, this paper quantitatively analyzed the spatial characteristics of urban update from two dimensions of location conditions and function... Through sorting out the data of urban renewal units in Shenzhen from 2010 to 2016, this paper quantitatively analyzed the spatial characteristics of urban update from two dimensions of location conditions and functional attributes, using social network analysis, community discovery and other methods.The research found that:(1) the urban functional network formed based on the update unit had obvious spatial agglomeration and hierarchical characteristics, forming the central-peripheral structure of "two mains and five sections", covering basically all the developed areas of Shenzhen city, and presenting the overall spatial structure of "dense west and sparse east";(2) based on the functional space of urban update unit, five relatively closely connected community groups were formed, whose characteristics mainly included:spatial integration, spatial coupling and spatial spillover effect;(3) the spatial structure formed by urban updates basically conformed to the spatial structure defined in the plan of "the 10 master plan". 展开更多
关键词 URBAN spatial structure social network analysis SHENZHEN URBAN UPDATE
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Comparative analyses of mitogenomes in the social bees with insights into evolution of long inverted repeats in the Meliponini
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作者 Yu-Ran Li Zheng-Wei Wang +1 位作者 Richard T.Corlett Wen-Bin Yu 《Zoological Research》 SCIE CSCD 2024年第1期160-175,共16页
The insect mitogenome is typically a compact circular molecule with highly conserved gene contents.Nonetheless,mitogenome structural variations have been reported in specific taxa,and gene rearrangements,usually the t... The insect mitogenome is typically a compact circular molecule with highly conserved gene contents.Nonetheless,mitogenome structural variations have been reported in specific taxa,and gene rearrangements,usually the tRNAs,occur in different lineages.Because synapomorphies of mitogenome organizations can provide information for phylogenetic inferences,comparative analyses of mitogenomes have been given increasing attention.However,most studies use a very few species to represent the whole genus,tribe,family,or even order,overlooking potential variations at lower taxonomic levels,which might lead to some incorrect inferences.To provide new insights into mitogenome organizations and their implications for phylogenetic inference,this study conducted comparative analyses for mitogenomes of three social bee tribes(Meliponini,Bombini,and Apini)based on the phylogenetic framework with denser taxonomic sampling at the species and population levels.Comparative analyses revealed that mitogenomes of Apini and Bombini are the typical type,while those of Meliponini show diverse variations in mitogenome sizes and organizations.Large inverted repeats(IRs)cause significant gene rearrangements of protein coding genes(PCGs)and rRNAs in Indo-Malay/Australian stingless bee species.Molecular evolution analyses showed that the lineage with IRs have lower dN/dS ratios for PCGs than lineages without IRs,indicating potential effects of IRs on the evolution of mitochondrial genes.The finding of IRs and different patterns of gene rearrangements suggested that Meliponini is a hotspot in mitogenome evolution.Unlike conserved PCGs and rRNAs whose rearrangements were found only in the mentioned lineages within Meliponini,tRNA rearrangements are common across all three tribes of social bees,and are significant even at the species level,indicating that comprehensive sampling is needed to fully understand the patterns of tRNA rearrangements,and their implications for phylogenetic inference. 展开更多
关键词 social bees PHYLOGENY Mitogenome structure Gene rearrangement Inverted repeats
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Design and implementation of dual-mode configurable memory architecture for CNN accelerator
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作者 山蕊 LI Xiaoshuo +1 位作者 GAO Xu HUO Ziqing 《High Technology Letters》 EI CAS 2024年第2期211-220,共10页
With the rapid development of deep learning algorithms,the computational complexity and functional diversity are increasing rapidly.However,the gap between high computational density and insufficient memory bandwidth ... With the rapid development of deep learning algorithms,the computational complexity and functional diversity are increasing rapidly.However,the gap between high computational density and insufficient memory bandwidth under the traditional von Neumann architecture is getting worse.Analyzing the algorithmic characteristics of convolutional neural network(CNN),it is found that the access characteristics of convolution(CONV)and fully connected(FC)operations are very different.Based on this feature,a dual-mode reronfigurable distributed memory architecture for CNN accelerator is designed.It can be configured in Bank mode or first input first output(FIFO)mode to accommodate the access needs of different operations.At the same time,a programmable memory control unit is designed,which can effectively control the dual-mode configurable distributed memory architecture by using customized special accessing instructions and reduce the data accessing delay.The proposed architecture is verified and tested by parallel implementation of some CNN algorithms.The experimental results show that the peak bandwidth can reach 13.44 GB·s^(-1)at an operating frequency of 120 MHz.This work can achieve 1.40,1.12,2.80 and 4.70 times the peak bandwidth compared with the existing work. 展开更多
关键词 distributed memory structure neural network accelerator reconfigurable arrayprocessor configurable memory structure
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An efficient shortest path approach for social networks based on community structure 被引量:2
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作者 Maoguo Gong Guanjun Li +2 位作者 Zhao Wang Lijia Ma Dayong Tian 《CAAI Transactions on Intelligence Technology》 2016年第1期114-123,共10页
Finding the shortest path (SP) in a large-scale network analysis between any two nodes is a tough but very significant task. The SP can help us to analyze the information spreading performance and research the laten... Finding the shortest path (SP) in a large-scale network analysis between any two nodes is a tough but very significant task. The SP can help us to analyze the information spreading performance and research the latent relationship in the weighted social network, and so on. As the size of the social network increases, the traditional SP algorithms have poor performance and there is not a suitable algorithm for weighted social network. Some features of the network analysis are beneficial to solve this problem, and community structure ignored by the traditional methods is one of the most important features. In this paper, we propose a shortest path algorithm based on community detection (SPCD) by integrating community detection algorithm with traditional search methods. SPCD constructs a community graph by using community structure to narrow the searching scope. The algorithm presented improves the time efficiency and maintains the accuracy scale of the SR Experimental results on five real-world networks demonstrate the effectiveness of the proposed methods for the SP problem. 展开更多
关键词 Shortest path Community structure Weighted social network
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