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Almond diversity and homozygosity define structure, kinship, inbreeding, and linkage disequilibrium in cultivated germplasm, and reveal genomic associations with nut and seed weight 被引量:3
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作者 Stefano Pavan Chiara Delvento +8 位作者 Rosa Mazzeo Francesca Ricciardi Pasquale Losciale Liliana Gaeta Nunzio D’Agostino Francesca Taranto Raquel Sanchez-Perez Luigi Ricciardi Concetta Lotti 《Horticulture Research》 SCIE 2021年第1期223-234,共12页
Almond[Prunus dulcis Miller(D.A.Webb)]is the main tree nut species worldwide.Here,genotyping-by-sequencing(GBS)was applied to 149 almond cultivars from the ex situ collections of the Italian Council for Agricultural R... Almond[Prunus dulcis Miller(D.A.Webb)]is the main tree nut species worldwide.Here,genotyping-by-sequencing(GBS)was applied to 149 almond cultivars from the ex situ collections of the Italian Council for Agricultural Research(CREA)and the Spanish National Research Council(CSIC),leading to the detection of 93,119 single-nucleotide polymorphisms(SNPs).The study of population structure outlined four distinct genetic groups and highlighted diversification between the Mediterranean and Californian gene pools.Data on SNP diversity and runs of homozygosity(ROHs)allowed the definition of kinship,inbreeding,and linkage disequilibrium(LD)decay in almond cultivated germplasm.Four-year phenotypic observations,gathered on 98 cultivars of the CREA collection,were used to perform a genome-wide association study(GWAS)and,for the first time in a crop species,homozygosity mapping(HM),resulting in the identification of genomic associations with nut,shell,and seed weight.Both GWAS and HM suggested that loci controlling nut and seed weight are mostly independent.Overall,this study provides insights on the almond cultivation history and delivers information of major interest for almond genetics and breeding.In a broader perspective,our results encourage the use of ROHs in crop science to estimate inbreeding,choose parental combinations minimizing the risk of inbreeding depression,and identify genomic footprints of selection for specific traits. 展开更多
关键词 linkage structure Italian
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Causal associations of brain structure with bone mineral density:a large-scale genetic correlation study 被引量:1
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作者 Bin Guo Chao Wang +7 位作者 Yong Zhu Zhi Liu Haitao Long Zhe Ruan Zhangyuan Lin Zhihua Fan Yusheng Li Shushan Zhao 《Bone Research》 SCIE CAS CSCD 2023年第3期574-585,共12页
In this study,we aimed to investigate the causal associations of brain structure with bone mineral density(BMD).Based on the genome-wide association study(GWAS)summary statistics of 1325 brain imaging-derived phenotyp... In this study,we aimed to investigate the causal associations of brain structure with bone mineral density(BMD).Based on the genome-wide association study(GWAS)summary statistics of 1325 brain imaging-derived phenotypes(BIDPs)of brain structure from the UK Biobank and GWAS summary datasets of 5 BMD locations,including the total body,femoral neck,lumbar spine,forearm,and heel from the GEFOS Consortium,linkage disequilibrium score regression(LDSC)was conducted to determine the genetic correlations,and Mendelian randomization(MR)was then performed to explore the causal relationship between the BIDPs and BMD.Several sensitivity analyses were performed to verify the strength and stability of the present MR outcomes.To increase confidence in our findings,we also performed confirmatory MR between BIDPs and osteoporosis.LDSC revealed that 1.93%of BIDPs,with a false discovery rate(FDR)<0.01,were genetically correlated with BMD.Additionally,we observed that 1.31%of BIDPs exhibited a significant causal relationship with BMD(FDR<0.01)through MR.Both the LDSC and MR results demonstrated that the BIDPs“Volume of normalized brain,”“Volume of gray matter in Left Inferior Frontal Gyrus,pars opercularis,”“Volume of Estimated Total Intra Cranial”and“Volume-ratio of brain segmentation/estimated total intracranial”had strong associations with BMD.Interestingly,our results showed that more left BIDPs were causally associated with BMD,especially within and around the left frontal region.In conclusion,a part of the brain structure causally influences BMD,which may provide important perspectives for the prevention of osteoporosis and offer valuable insights for further research on the brain-bone axis. 展开更多
关键词 PREVENTION structure linkage
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IMPROVED HOMOTOPY ITERATION METHOD AND APPLIED TO THE NINE-POINT PATH SYNTHESIS PROBLEM FOR FOUR-BAR LINKAGES 被引量:1
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作者 Zhang Jian Chen Yong (School of Mechanical Engineering, Southwest Jiaotong University) 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2000年第1期10-16,共7页
A new algorithm called homotopy iteration method based on the homotopy function is studied and improved. By the improved homotopy iteration method, Polynomial systems with high Order and deficient can be solved fast a... A new algorithm called homotopy iteration method based on the homotopy function is studied and improved. By the improved homotopy iteration method, Polynomial systems with high Order and deficient can be solved fast and efficiently comparing to the original homotopy iteration method. Numerical examples for the ninepoint path synthesis of four-bar linkages show the advantages and efficiency of the improved homotopy iteration method. 展开更多
关键词 Homotopy function Homotopy iteration method Nine-point path synthesis four-bar linkage
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Evolution of economic linkage network of the cities and counties on the northern slope of the Tianshan Mountains,China
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作者 YANG Zeyu ZHANG Shubao +4 位作者 LEI Jun ZHANG Xiaolei TONG Yanjun DUAN Zuliang FAN Liqin 《Regional Sustainability》 2023年第2期173-184,共12页
The exchanges between cities and counties in the northern slope economic belt of Tianshan Mountains(NSEBTM)are increasingly frequent and the economic linkages are increasingly close,but the spatial distribution of eco... The exchanges between cities and counties in the northern slope economic belt of Tianshan Mountains(NSEBTM)are increasingly frequent and the economic linkages are increasingly close,but the spatial distribution of economic development and linkages among the cities and counties within NSEBTM is uneven.Therefore,it is of great significance to study the evolution of spatial-temporal pattern of the economic linkage network of cities and counties on NSEBTM to promote the coordinated and integrated development of the regional economy on NSEBTM.In this study,we used the modified gravity model and social network analysis method to analyze the spatio-temporal evolution characteristics of the economic linkage network structure of cities and counties on NSEBTM in 2000,2010,and 2020.The results showed that the comprehensive development quality level of cities and counties on NSEBTM increased from 2000 to 2020,its growth rate also increased,and its gap between cities and counties continued expanding.Both the spatial distribution patterns of the comprehensive development quality level of cities and counties on NSEBTM in 2000 and 2010 were presented as“high in the middle and low at both ends”,while the spatial distribution pattern of 2020 was exhibited as“high value and low value staggered”.The total amount of external economic linkages of cities and counties on NSEBTM showed an obvious upward trend,and its gap between cities and counties continued expanding,presenting a pattern of“a strong middle section and weak ends”.The direction of economic linkages of NSEBTM existed obvious central orientation and geographical proximity.The density of economic linkage network of NSEBTM increased from 2000 to 2020,and the structure of economic linkage network changed from single-core structure centered with Urumqi City to multicore structure centered with Urumqi City,Karamay City,Shihezi City,and Changji City,shifting from unbalanced development to balanced development.In the future,we should accelerate the construction of urban agglomeration on NSEBTM,cultivate a modern Urumqi metropolitan area,improve comprehensive development quality of the cities and counties at the eastern and western ends,strengthen the intensity of economic linkages between cities and counties,optimize the economic linkage network,and promote the coordinated and integrated development of regional economy. 展开更多
关键词 Entropy method Economic linkages Gravity model Network structure Social network analysis Northern slope economic belt of Tianshan Mountains China
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Complete Real Solution of the Five-orientation Motion Generation Problem for a Spherical Four-bar Linkage 被引量:1
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作者 ZHUANG Yufeng ZHANG Ying DUAN Xuechao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第2期258-266,共9页
For a spherical four-bar linkage,the maximum number of the spherical RR dyad(R:revolute joint)of five-orientation motion generation can be at most 6.However,complete real solution of this problem has seldom been st... For a spherical four-bar linkage,the maximum number of the spherical RR dyad(R:revolute joint)of five-orientation motion generation can be at most 6.However,complete real solution of this problem has seldom been studied.In order to obtain six real RR dyads,based on Strum's theorem,the relationships between the design parameters are derived from a 6th-degree univariate polynomial equation that is deduced from the constraint equations of the spherical RR dyad by using Dixon resultant method.Moreover,the Grashof condition and the circuit defect condition are taken into account.Given the relationships between the design parameters and the aforementioned two conditions,two objective functions are constructed and optimized by the adaptive genetic algorithm(AGA).Two examples with six real spherical RR dyads are obtained by optimization,and the results verify the feasibility of the proposed method.The paper provides a method to synthesize the complete real solution of the five-orientation motion generation,which is also applicable to the problem that deduces to a univariate polynomial equation and requires the generation of as many as real roots. 展开更多
关键词 spherical four-bar linkage five-orientation motion generation Sturm's theorem adaptive genetic algorithm(AGA
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The occurrence,inheritance,and segregation of complex genomic structural variation in synthetic Brassica napus
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作者 Dandan Hu Jin Lu +12 位作者 Wenwen Li Yinghui Yang Junxiong Xu Han Qin Hao Wang Yan Niu Huaiqi Zhang Qingqing Liu Xiangxiang He Annaliese S.Mason JChris Pires Zhiyong Xiong Jun Zou 《The Crop Journal》 SCIE CSCD 2024年第2期515-528,共14页
"Synthetic"allopolyploids recreated by interspecific hybridization play an important role in providing novel genomic variation for crop improvement.Such synthetic allopolyploids often undergo rapid genomic s... "Synthetic"allopolyploids recreated by interspecific hybridization play an important role in providing novel genomic variation for crop improvement.Such synthetic allopolyploids often undergo rapid genomic structural variation(SV).However,how such SV arises,is inherited and fixed,and how it affects important traits,has rarely been comprehensively and quantitively studied in advanced generation synthetic lines.A better understanding of these processes will aid breeders in knowing how to best utilize synthetic allopolyploids in breeding programs.Here,we analyzed three genetic mapping populations(735 DH lines)derived from crosses between advanced synthetic and conventional Brassica napus(rapeseed)lines,using whole-genome sequencing to determine genome composition.We observed high tolerance of large structural variants,particularly toward the telomeres,and preferential selection for balanced homoeologous exchanges(duplication/deletion events between the A and C genomes resulting in retention of gene/chromosome dosage between homoeologous chromosome pairs),including stable events involving whole chromosomes("pseudoeuploidy").Given the experimental design(all three populations shared a common parent),we were able to observe that parental SV was regularly inherited,showed genetic hitchhiking effects on segregation,and was one of the major factors inducing adjacent novel and larger SV.Surprisingly,novel SV occurred at low frequencies with no significant impacts on observed fertility and yield-related traits in the advanced generation synthetic lines.However,incorporating genome-wide SV in linkage mapping explained significantly more genetic variance for traits.Our results provide a framework for detecting and understanding the occurrence and inheritance of genomic SV in breeding programs,and support the use of synthetic parents as an important source of novel trait variation. 展开更多
关键词 ALLOPOLYPLOID Large Genome structural variation linkage mapping Synthetic polyploids Inheritance and segregation
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Structure optimal design research on backfill hydraulic support 被引量:8
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作者 张强 张吉雄 +2 位作者 齐文跃 周楠 邰阳 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第7期1637-1646,共10页
Backfill hydraulic support is the key equipment in achieving coal mining and solid backfilling simultaneously in solid backfill mining technology.Based on the summary and analysis of main types,basic structural proper... Backfill hydraulic support is the key equipment in achieving coal mining and solid backfilling simultaneously in solid backfill mining technology.Based on the summary and analysis of main types,basic structural properties and filed application of backfill hydraulic support,this work has firstly proposed the basic principle of backfill hydraulic support optimization design and provided the method of optimal design of key structural components,like four-bar linkage,rear canopy and tamping structure;the method is further elaborated as changing hinging position of upper bar to optimize four-bar linkage,by lengthening or shortening the rear canopy to optimize length ratio of canopy;and by changing length and hinging position of tamping structure as well as suspension height of backfill scrape conveyor to realize optimization of tamping structure.On this basis,the process of optimal design of backfill hydraulic support is built.The optimal design case of ZC5200/14.5/30 six columns-four bar linkage used in 7203 W workface of Zhaizhen Coal Mine shows that the backfill properties like horizontal roof gap,vertical horizontal gap,tamping angle and tamping head gap are improved obviously through optimizing four-bar linkage,canopy length and tamping structure according to the optimal design method proposed in this work. 展开更多
关键词 BACKFILL hydraulic support structure optimal design four-bar linkage REAR CANOPY TAMPING structure
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Topology Structure Synthesis and Analysis of Spatial Pyramid Deployable Truss Structures for Satellite SAR Antenna 被引量:24
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作者 WANG Yan DENG Zongquan +2 位作者 LIU Rongqiang YANG Hui GUO Hongwei 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第4期683-692,共10页
Many attentions for structural synthesis are paid to planar linkages and parallel mechanisms, while design novel pyramid deployable truss structure(PDTS) of satellite SAR mainly depends on experience of designer. To... Many attentions for structural synthesis are paid to planar linkages and parallel mechanisms, while design novel pyramid deployable truss structure(PDTS) of satellite SAR mainly depends on experience of designer. To design novel configuration of PDTS, a two-step topology structure synthesis and analysis approach is proposed. Firstly, a conceptual configuration of PDTS is synthesized. Weighted graph and weighted adjacency matrix are established to realize topological description for PDTS. Graph properties are then summarized to distinguish differentia between PDTS and other type structures. According to graph properties, a procedure for synthesis conceptual configuration of PDTS is presented. Secondly, join relationship of components in a PDTS is analyzed. Kinematic chain and corresponding incidence/adjacency matrix are employed to analyze join relationship of PDTS. Properties and simplified rules of kinematic chain are extracted to construct kinematic chain. A procedure for construction kinematic chain of PDTS is then established. Finally, with this two-step approach all 11 rectangular pyramid deployable structures whose folded state is planar are discovered and their kinematic chains are constructed. Based on synthesis results, a novel deployable support structure for satellite SAR is designed. The proposed research can be applied to obtain some novel PDTSs, which is of great importance to design some novel deployable support structures for satellite SAR antenna. 展开更多
关键词 structural synthesis deployable truss structure spatial linkage graph theory SAR antenna
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Structure and properties of bone-like-nanohydroxyapatite/gelatin/polyvinyl alcohol composites 被引量:3
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作者 Feng Wang Enyan Guo +2 位作者 Enmin Song Ping Zhao Jinhua Liu 《Advances in Bioscience and Biotechnology》 2010年第3期185-189,共5页
Bone-like nanohydroxyapatite powders (b-nanoHA) were synthesized in simulated body fluid (SBF). The b-nanoHA, gelatin (Gel) and Polyvinyl Alcohol (PVA) were used to prepare bone-like composites (b-nanoHA/ Gel/PVA) at ... Bone-like nanohydroxyapatite powders (b-nanoHA) were synthesized in simulated body fluid (SBF). The b-nanoHA, gelatin (Gel) and Polyvinyl Alcohol (PVA) were used to prepare bone-like composites (b-nanoHA/ Gel/PVA) at room temperature. Characterizations of b-nanoHA powders and b-nanoHA/Gel/PVA composites were investigated by using X-ray diffraction (XRD), transmission electron microscopy (TEM), High-resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR). Bending strength and compressive strength of the composite were tested. It was found that microstructure of the b-nanoHA powders was whisker shape and its crystalline degree was low similar to natural bone, bending strength and compressive strength of the b-nanoHA/Gel/PVA composite depended on the mixing ratio of HA, Gel and PVA, and also PVA could induce the network formation in the b-nanoHA/Gel/ PVA composite. 展开更多
关键词 SBF b-nanoHA/Gel COMPOSITES structure Mechanical Strength Cross-linkage
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TOWARDS SPATIAL LINKAGE PATTERNS OF INDUSTRIAL ORGANIZATIONS IN CHINA
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作者 Fei Hongping(Institute of Macro-Economic Research, State Planning Commission, Beijing 100055People’s Republic of China) 《Journal of Geographical Sciences》 SCIE CSCD 1995年第4期16-32,共17页
The paper attempts to examine the relationships botween industrial organizations and their environments from an essentially spatial perspective and organizational theory, and inteqrate the generalizations derived from... The paper attempts to examine the relationships botween industrial organizations and their environments from an essentially spatial perspective and organizational theory, and inteqrate the generalizations derived from organizational theory and industrial geography o identify spatial linkage pattems created by the enterprises, both in the aggregate and individually These issues are organized around three elements. From the many organizational and environmental factors which might influence the spatial linkage patterns, six have been selected for analysis. These factors were highly correlated with value or volume of spatial linkages. Changes of spatial linkage pattems over time were analyzed based on a representative sample of the Nanjing Automotive Industrial Corporation, and findings with case studies were illustrated. 展开更多
关键词 enterprise organization spatial linkages organizational structure external environment
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A generalization of Kempe’s linkages
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作者 MAO De-can LUO Yao-zhi YOU Zhong 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第7期1084-1090,共7页
A new, general type of planar linkages is presented, which extends the classical linkages developed by Kempe consisting of two single-looped kinematic chains of linkages, interconnected by revolute hinges. Together wi... A new, general type of planar linkages is presented, which extends the classical linkages developed by Kempe consisting of two single-looped kinematic chains of linkages, interconnected by revolute hinges. Together with a locking device, these new linkages have only one degree of freedom (DOF), which makes them ideal for serving as deployable structures for different purposes. Here, we start with a fresh matrix method of analysis for double-loop planar linkages, using 2D transformation matrices and a new symbolic notation. Further inspection for one case of Kempe’s linkages is provided. Basing on the inspection, by means of some novel algebraic and geometric techniques, one particularly fascinating solution was found. Physical models were built to show that the derivation in this paper is valid and the new mechanisms are correct. 展开更多
关键词 变换基质 建筑物 建筑设计 建筑结构
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高通量测序法胚胎植入前染色体结构变异检测评价
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作者 孙楠 许建霞 +4 位作者 赵丁丁 张文新 孔令印 黄杰 曲守方 《分子诊断与治疗杂志》 2024年第6期993-996,共4页
目的 使用建立的染色体结构异常的家系样本,评价基于高通量测序法的胚胎植入前染色体结构异常检测试剂盒的性能。方法 首先将家系中模拟胚胎细胞样本进行单细胞全基因组扩增,然后扩增产物和家系中其他样本的DNA进行酶切打断、接头连接... 目的 使用建立的染色体结构异常的家系样本,评价基于高通量测序法的胚胎植入前染色体结构异常检测试剂盒的性能。方法 首先将家系中模拟胚胎细胞样本进行单细胞全基因组扩增,然后扩增产物和家系中其他样本的DNA进行酶切打断、接头连接和磁珠富集等操作完成文库构建。将文库进行定量,使用高通量测序仪进行测序。使用生物信息学软件把测序得到的序列与人基因组参考序列比对,并进行SNP分析。结合家系亲缘关系筛选出有效SNP位点,构建家系单体型图谱。最后对易位断点上下游紧密连锁的区域进行分析,鉴别出易位携带型胚胎和正常型胚胎。结果 参考样本的测序染色体拷贝数变异(CNV)结果,确定1号染色体断点位置为chr1:194390001,胚胎样本的分型有效区域为断点上游1 Mb区域(chr1:193390001-194390001),有63个有效位点;11号染色体断点位置为chr11:133780001,胚胎样本分型有效区域为断点上游1Mb区域(chr11:132780001-133780001),有36个有效位点。通过单体型分型判断胚胎样本是携带型。结论 评价的胚胎植入前染色体结构异常检测试剂盒能够准确检出染色体结构异常的家系样本,为临床提供了一种新的染色体结构变异检测方法。 展开更多
关键词 平衡易位 罗氏易位 胚胎植入前遗传学检测 结构变异 单体型连锁分析
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知识网络视角下科学、技术、产业间创新驱动关系识别方法研究
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作者 王超 许海云 +1 位作者 齐砚翠 武华维 《情报学报》 CSCD 北大核心 2024年第1期10-24,共15页
开展科学、技术、产业之间创新驱动关系研究,对于实现科学发现、技术创新与产业的深度有效融合与发展具有重要意义。本文从知识网络视角展开科学、技术、产业间创新驱动关系识别方法研究。首先,通过构建时效知识网络,利用社区网络结构... 开展科学、技术、产业之间创新驱动关系研究,对于实现科学发现、技术创新与产业的深度有效融合与发展具有重要意义。本文从知识网络视角展开科学、技术、产业间创新驱动关系识别方法研究。首先,通过构建时效知识网络,利用社区网络结构熵来表征知识网络结构特征;其次,利用网络结构特征信息间的传递熵探究创新过程中科学、技术、产业三个系统相互驱动的关系;再其次,采用互信息探测主要驱动关系下知识传递路径的变化特点;最后,以再生医学(干细胞)领域作为实证对象,实证研究发现不同时间阶段,科学、技术、产业之间的相互驱动关系会发生转变,三者知识传递路径上知识内容前后继承关系也不同,科学驱动技术过程中的知识传递路径继承性特征持续增强,而技术驱动科学过程中的知识传递路径继承性呈现不稳定、非连续性特征。此外,通过多种方式论证了本文方法的科学有效性,可以用于其他创新领域科学、技术、产业间创新驱动关系的识别。 展开更多
关键词 知识网络 科学-技术-产业关联 驱动关系 结构熵
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人致荷载作用下钢结构连廊动力响应分析
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作者 张秀华 张巧玲 《低温建筑技术》 2024年第3期89-93,共5页
为研究钢结构连廊在人致荷载下的动力特性,文中以洛阳理工学院九都校区钢结构连廊为研究对象,采用Midas Gen有限元软件以4种不同的工况对连廊结构进行时程分析,以舒适度双控标准对结构的动力响应进行评价。结果表明连廊的竖向自振频率大... 为研究钢结构连廊在人致荷载下的动力特性,文中以洛阳理工学院九都校区钢结构连廊为研究对象,采用Midas Gen有限元软件以4种不同的工况对连廊结构进行时程分析,以舒适度双控标准对结构的动力响应进行评价。结果表明连廊的竖向自振频率大于3 Hz,4种工况下的峰值加速度均小于0.15 m/s^(2),满足规范限值要求。研究为设计者提供了一种评价结构舒适度的方法,也为类似工程结构的舒适度分析提供参考。 展开更多
关键词 连廊结构 人致荷载 时程分析 舒适度评价
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飞行器机翼变形驱动机构研究
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作者 郭广宇 陈青山 高宏 《机械科学与技术》 CSCD 北大核心 2024年第3期540-545,共6页
为了优化飞行器气动特性,提升飞行效率,研究用于连续变弯度机翼的多级连杆驱动机构。采用ANSYS流体分析功能研究最大弯曲角度下变弯度机翼的气动特性;采用ANSYS静力学分析功能研究极限载荷条件下驱动机构的结构强度;并通过仿真分析与样... 为了优化飞行器气动特性,提升飞行效率,研究用于连续变弯度机翼的多级连杆驱动机构。采用ANSYS流体分析功能研究最大弯曲角度下变弯度机翼的气动特性;采用ANSYS静力学分析功能研究极限载荷条件下驱动机构的结构强度;并通过仿真分析与样机测试对驱动机构的运动情况进行研究。研究结果表明:变形机翼获得升力系数为1.4,所受最大气流动压1 078 Pa,小于下表面屈服气流动压4 916 Pa;驱动机构所受最大应力37.3 MPa,小于结构屈服强度55.2 MPa;机翼弯曲变形角度可达±25°,满足了飞行器对改善飞行特性方面的需要。 展开更多
关键词 驱动机构 多级连杆 变弯度机翼 结构强度 样机测试
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渤海湾盆地惠民凹陷中央隆起带张扭性断裂演化的构造物理模拟研究
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作者 王衍迪 王毛毛 +2 位作者 闫兵 汤梦静 贾红义 《高校地质学报》 CAS CSCD 北大核心 2024年第1期22-35,共14页
惠民凹陷位于渤海湾盆地济阳坳陷西部,新生代时期经历了南北向伸展,形成了典型的“北断南超”半地堑结构。平面上,惠民凹陷中央隆起带发育了NE至近EW向的张扭断裂体系;垂向上,中央隆起带断裂体系从深部到浅部呈现出由雁列式分段到逐渐... 惠民凹陷位于渤海湾盆地济阳坳陷西部,新生代时期经历了南北向伸展,形成了典型的“北断南超”半地堑结构。平面上,惠民凹陷中央隆起带发育了NE至近EW向的张扭断裂体系;垂向上,中央隆起带断裂体系从深部到浅部呈现出由雁列式分段到逐渐连接贯通的特征。目前对惠民凹陷中央隆起带断裂体系的结构特征有了较好的刻画,但是对于该断裂体系形成的运动学过程及其控制因素仍然停留在描述阶段。文章设计了一组张扭构造物理模拟实验,以探究惠民中央隆起带断裂构造演化过程及其控制因素。实验再现了惠民凹陷中央隆起带断裂体系在平面上由早期孤立分段、侧向传播、最终贯通的三个阶段;在剖面上也很好对应了中央隆起带沿走向由共轭断裂系向阶梯式断裂的结构转变特征。基于粒子成像测速(PIV)的应变分析,文章构建了三阶段的应变—断层距离统计图,揭示了各分段断裂由早期无连接,经历侧向生长,从软连接到硬连接的构造演化过程。研究证实在南北向区域伸展作用下,盆地基底NEE向先存断裂的活化是惠民凹陷中央隆起带张扭构造形成的根本原因。文章利用砂箱构造物理模拟实验揭示了惠民凹陷中央隆起带断裂发育的机制,可为类似的张扭性断陷盆地的断裂演化与油气成藏研究提供有益的启示。 展开更多
关键词 构造物理模拟 张扭构造 断层连接 构造转换带 惠民凹陷 中央隆起带
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云南省普洱市“景景镇”区域经济联动发展研究
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作者 司翠 赵勤 《普洱学院学报》 2024年第3期36-45,共10页
“景景镇”地处云南省普洱市北部,涵盖景谷、镇沅、景东三个县。“景景镇”地区地域相连、历史相承、资源相近、交通衔接,区域经济联动发展已具备良好的基础,在综合分析“景景镇”区域经济联动的可行性与困境基础上,通过区域经济联动评... “景景镇”地处云南省普洱市北部,涵盖景谷、镇沅、景东三个县。“景景镇”地区地域相连、历史相承、资源相近、交通衔接,区域经济联动发展已具备良好的基础,在综合分析“景景镇”区域经济联动的可行性与困境基础上,通过区域经济联动评价体系对“景景镇”区域经济联动进行测度评价,采用产业结构差异系数、区位熵和灰色关联度对“景景镇”区域产业联动进行实证分析,并提出“景景镇”区域经济联动发展的相应对策和建议。 展开更多
关键词 区域经济联动 区域经济联动评价体系 区域产业联动 差异性 区位熵 灰色关联度
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基于物联网技术的水电站智能安防系统设计
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作者 张建新 郑明友 《人工智能科学与工程》 CAS 北大核心 2024年第2期18-26,共9页
水电站智能安防系统数据传输速度较慢,导致系统反应时间较长。因此,设计基于物联网技术的水电站智能安防系统。使用5800 bit/s的单片机为系统硬件中间控制器,通过活动数据对象(ADO)接口采集与写入数据,完成安防系统硬件设计;设置数据库... 水电站智能安防系统数据传输速度较慢,导致系统反应时间较长。因此,设计基于物联网技术的水电站智能安防系统。使用5800 bit/s的单片机为系统硬件中间控制器,通过活动数据对象(ADO)接口采集与写入数据,完成安防系统硬件设计;设置数据库的对应关系,采集并处理水电站状态数据,将处理后的数据存储至数据库,基于物联网技术,使用网状结构的拓扑结构,传输存储的数据,设定智能安防子系统的联动关系,按照联动关系检测现场入侵,设计按需求执行的特定代码,当判定为入侵时系统发出报警,完成安防系统软件设计。实验结果表明,在水电站两个区域测试该系统,其反应时间较短,在2 s内快速反映出水电站各个点位出现的异常,应用效果较好。 展开更多
关键词 物联网技术 水电站 智能安防系统 数据库 网状结构 联动关系 激光围栏
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矿用卡轨车气动压绳梁的设计
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作者 王乃松 许延晖 《煤炭与化工》 CAS 2024年第1期103-106,共4页
为了解决无极绳牵引卡轨车在使用过程中压绳轮磨损导致的跳绳现象,本文基于部分矿区采用的人工拆除和安装压绳滑轮来防止跳绳的操作步骤,设计开发了一种气动压绳梁装置。该装置通过气动系统与压绳梁结构之间的装置联动,利用气缸的气动... 为了解决无极绳牵引卡轨车在使用过程中压绳轮磨损导致的跳绳现象,本文基于部分矿区采用的人工拆除和安装压绳滑轮来防止跳绳的操作步骤,设计开发了一种气动压绳梁装置。该装置通过气动系统与压绳梁结构之间的装置联动,利用气缸的气动力实现压绳梁对于钢丝绳的压紧和放松,再由另外一个气缸完成销子的插拔,从而完成一个工作循环。该装置的使用,可以取代原本涉及人工的部分,提高生产工作的安全保障以及生产效率,在同类型的各个矿区中都可以进行推广使用。 展开更多
关键词 跳绳现象 气动 气缸 结构设计 装置联动
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Environmental Quality,Energy Consumption and Economic Inequality in China:Smooth Structural Shifts and Causal Linkages
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作者 Shengxia XU Jiahui YANG Qiang LIU 《Journal of Systems Science and Information》 CSCD 2023年第5期535-561,共27页
The space-temporal evolution of economic inequality is examined with Markov chain test method,and the dynamic interrelationships among environmental quality,energy consumption,and economic inequality in China from the... The space-temporal evolution of economic inequality is examined with Markov chain test method,and the dynamic interrelationships among environmental quality,energy consumption,and economic inequality in China from the province-level are tested by focusing on accounting for structural shifts in causal linkages in this paper.We first employ the Toda-Yamamoto causality framework and then augment it with a Fourier approximation which captures structural changes as a smooth process.The empirical findings show that taking into account smooth structural shifts is important for the causal linkages between economic inequality and energy consumption,and also between environmental quality and energy consumption.The causality analysis with structural changes provides a causal linkage between economic inequality and energy consumption in 26 out 30 provinces and a causal linkage between environmental quality and energy consumption in 7 out 30 provinces,while the quantities are 22 out 30 and 5 out 30 respectively when not accounting for structural shifts.These findings are consistent with the fact that provincial economics in China have experienced structural changes in economy-environment-energy sectors.We also conduct additional analyses which point out that regional and cyclical dependency matter for the causal relationships,and the method of HP filtering can not effectively solve the problem of smooth shifts in economy-environment-energy causality. 展开更多
关键词 environmental quality energy consumption economic inequality causal linkages structural shifts China
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