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Genetic diversity and a population structure analysis of accessions in the Chinese cowpea [Vigna unguiculata(L.)Walp.]germplasm collection

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The Crop Journal 2017年第5期5卷 363-372页

作者： Honglin Chen Hong Chen liangliang hu Lixia Wang Suhua Wang Ming Li Wang Xuzhen Cheng National Key Facility for Crop Gene Resources and Genetic Improvement Institute of Crop Science Chinese Academy of Agricultural Sciences Development Center of Science and Technology Ministry of Agriculture PR China United States Department of Agriculture Agricultural Research Service Plant Genetic Resources Conservation Unit

Cowpea(Vigna imguicuiata) is an important legume crop with diverse uses. The species is presently a minor crop, and evaluation of its genetic diversity has been very limited. In this study, a total of 200 genic and 100 genomic simple sequence repeat(SSR) markers were developed from cowpea unigene and genome sequences, respectively. Among them, 27 genic and 27 genomic SSR markers were polymorphic and were used for assessment of genetic diversity and population structure in 105 selected cowpea accessions. A total of 155 alleles and 2.9 alleles per marker were identified, and the average polymorphic information content(PIC) value was 0.3615. The average PIC of genomic SSRs(0.3996) was higher than that of genic SSRs(0.3235), and most of the polymorphic genomic SSRs were composed of di-and trinucleotide repeats(51.9% and 37.0% of all loci, respectively). The low level of detected genetic diversity may be attributed to a severe genetic bottleneck that occurred during the cowpea domestication process. The accessions were classified by structure and cluster analysis into four subgroups that correlated well with their geographic origins or collection sites. The classification results were also consistent with the results from principal coordinate analysis and can be used as a guide during future germplasm collection and selection of accessions as breeding materials for cultivar improvement. The newly developed genic and genomic SSR markers described in this study will be valuable genomic resources for the assessment of genetic diversity, population structure, evaluation of germplasm accessions, construction of genetic maps, identification of genes of interest,and application of marker-assisted selection in cowpea breeding programs.

关键词： Vigna unguiculata (L.) Walp Cultivated cowpea collection Microsatellite marker Genetic diversity Population structure

Coupling Rice with Fish for Sustainable Yields and Soil Fertility in China

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Rice science 2020年第3期27卷 175-179页

作者： GUO Liang hu liangliang ZHAO Lufeng SHI Xiaoyu JI Zijun DING Lilian REN Weizheng ZHANG Jian TANG Jianjun CHEN Xin College of Life Sciences Zhejiang UniversityHangzhou 310058China

About 30 million hectares of rice are cultivated annually in China(FAOSTAT,2019).Because most rice fields are wellirrigated and suitable for fish living(‘fish’here refers to various aquatic animals like carps,prawns,crabs,soft shell turtles,etc.)(Fernando,1993),many efforts have been made to determine how well rice farming and aquaculture can be coupled as a rice-fish system(RFS),of which the same land and water produces both rice and aquatic *** the technological guidance of RFSs and political supports from the Ministry of Agriculture and Rural Affairs of China since 2010(Supplemental Table 1),multiple types of large-scale,high-efficiency and technologically intensive RFSs are now being demonstrated in the main rice-growing areas of China(National Fisheries Technology Extension Centre,2019),and in total about 1.2 million hectares of rice fields are under RFSs.

关键词： cultivated annually Sustainable

Processing and Analysis of Multi-antenna GNSS/INS Fully Combined Model

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Processing and Analysis of Multi-antenna GNSS/INS Fully Comb...

基于距离区间概率测距的无线传感器网络定位算法研究

第十三届中国卫星导航年会

作者： liangliang hu Jin Wang Shengli Wang Haonan Cui College of Geodesy and Geomatics Shandong University of Science and Technology

Attitude measurement provides important decision information for navigation and positioning of moving vehicles. At present, the single-antenna GNSS/INS system has a limitation in performance and cost. This paper proposes to obtain the high-precision absolute attitude information of the moving carrier in real-time through the fusion of multi-antenna GNSS and INS. Since GNSS navigation is greatly affected by the external observation environment, it reduces the navigation and positioning results in the full combination mode. In this paper, the method of constructing the adaptive measurement noise model is presented by using the PDOP value of GNSS observation information and whether the ambiguity is fixed. The position, velocity and attitude of the moving carrier were obtained by the multi-antenna GNSS/INS adaptive Kalman filtering algorithm model. The results show that the position accuracy of GNSS/INS is 0.067 m, 0.044 m and 0.058 m, respectively. The speed-accuracy is 0.007 m/s, 0.006 m/s and 0.006 m/s respectively. The attitude accuracy is 0.011°, 0.015° and 0.085°. Experimental results show that multi-antenna GNSS/INS can realize high-precision and highly reliable positioning, velocity measurement and attitude measurement services of the carrier.

关键词： Multi-antenna GNSS/INS full combination adaptive noise measurement model adaptive Kalman filter

来源： cnki会议评论

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电脑与电信 2015年第5期 13-14,23页

作者：胡良梁重庆第二师范学院重庆400067

基于经验的传播模型在实际应用中存在多值问题,导致RSSI与距离并非一一映射。本文提出了一种改进的MDS-MAP定位算法,该算法利用基于距离区间概率的测距模型,消除多值问题对测距模型精度的影响,从而提高测距模型的测量精度。通过仿真结... 详细信息

基于经验的传播模型在实际应用中存在多值问题,导致RSSI与距离并非一一映射。本文提出了一种改进的MDS-MAP定位算法,该算法利用基于距离区间概率的测距模型,消除多值问题对测距模型精度的影响,从而提高测距模型的测量精度。通过仿真结果表明,改进的算法与传统的MDS-MAP定位算法相比,算法具有更好的定位精度。

关键词：无线传感器网络测距模型接收信号强度多值问题 MDS-MAP方法

基于评价相似度对WSN声誉系统合谋攻击的检测机制

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计算机应用 2013年第8期33卷 2222-2224,2231页

作者：王勇袁巢燕唐靖胡良梁重庆理工大学计算机科学与工程学院重庆400054

针对无线传感器网络(WSN)声誉系统中可能存在的多个恶意节点合谋攻击网络节点,并影响其准确定位等安全问题,提出了恶意推荐(BS)合谋攻击团及其检测机制(BSCD),并给出了该机制的实现方法。该机制通过对推荐节点进行异常检测,分析推荐节... 详细信息

针对无线传感器网络(WSN)声誉系统中可能存在的多个恶意节点合谋攻击网络节点,并影响其准确定位等安全问题,提出了恶意推荐(BS)合谋攻击团及其检测机制(BSCD),并给出了该机制的实现方法。该机制通过对推荐节点进行异常检测,分析推荐节点间的评价行为相似度,有效检测出存在的合谋攻击团,从而降低其对声誉系统的破坏和影响。仿真实验表明,BSCD在检测和抵制BS合谋攻击团方面效果显著,有效提高了声誉系统中恶意节点检测率和整个系统抵抗恶意节点破坏的能力。

关键词：无线传感器网络声誉系统合谋攻击恶意节点评价相似度

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基于分布式信誉评价的低能耗安全定位算法

计算机应用 2013年第7期33卷 1802-1804,1808页

作者：王勇袁巢燕唐靖胡良梁重庆理工大学计算机科学与工程学院重庆400054

针对无线传感器网络中节点安全定位和能耗问题,提出了一种基于分布式信誉评价的低能耗安全定位算法。该算法引入簇头节点中可靠节点表(TNT)和备份簇头节点的概念,通过查找TNT快速定位可靠信标节点,并且备份簇头节点协助、监督簇头节点,... 详细信息

针对无线传感器网络中节点安全定位和能耗问题,提出了一种基于分布式信誉评价的低能耗安全定位算法。该算法引入簇头节点中可靠节点表(TNT)和备份簇头节点的概念,通过查找TNT快速定位可靠信标节点,并且备份簇头节点协助、监督簇头节点,减轻簇头节点的工作负荷,且参与信标节点信誉值整合过程,增强了信标节点的可靠性和完整性,提高了节点定位的效率和安全性,降低了系统能耗,提高了恶意节点检测率。仿真实验表明,在恶意节点存在的环境中,该算法能有效提高恶意节点的检测率,减少定位误差,削弱恶意节点对定位系统的破坏和影响,实现节点的安全定位。

关键词：无线传感器网络安全定位信誉评价低能耗定位算法

基于三维精细化动力学模型的局部模态获取技术

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Aerospace China 2023年第2期24卷 52-56页

作者： TANG Yuhua YANG Bing MAO Yuming WU Tian hu liangliang Aerospace System Engineering Shanghai Shanghai 201109

Structural dynamic problems encountered within launch vehicles are sometimes related to entire dynamic characteristics of the vehicle,and sometimes related to local dynamic characteristics of some parts of *** acquire local dynamic characteristics,it usually requires the building of a three-dimensional detailed FEM *** is important that the simulation of mass and stiffness of local part is *** local mode acquisition of a gas tank and its bracket installed in the inter-tank section is taken as an example in this *** can be seen that the local modes are consistent with the section modal test ***,the verified three-dimensional detailed FEM model of the inter-tank section is assembled within the entire launch vehicle,and the local modes of the gas tank and its bracket under flight conditions are predicted.

关键词： launch vehicle local mode three-dimensional detailed FEM model

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煤矿悬臂式掘进机伸缩结构的设计

机械管理开发 2020年第7期35卷 12-13页

作者：胡亮亮潞安集团五阳煤矿山西长治046205

总结分析了现有悬臂伸缩结构形式在用于大功率重型岩巷掘进机时存在的问题及缺陷,并设计了一种新型伸缩结构,在改善伸缩结构强度、刚度的基础上,通过特殊的设计解决了方箱式结构加工工艺性差的问题。通过设计分析,确保该结构的可靠性、... 详细信息

总结分析了现有悬臂伸缩结构形式在用于大功率重型岩巷掘进机时存在的问题及缺陷,并设计了一种新型伸缩结构,在改善伸缩结构强度、刚度的基础上,通过特殊的设计解决了方箱式结构加工工艺性差的问题。通过设计分析,确保该结构的可靠性、稳定性,以期为解决岩巷纵轴掘进机长期以来无法实现悬臂伸缩功能的问题提供新的思路。

关键词：悬臂式掘进机重型伸缩结构

亿欣煤业15~#煤综采工作面地表岩移观测站的设计

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山西煤炭 2019年第2期39卷 54-56,83页

作者：呼亮亮山西晋煤集团晋圣矿业投资有限公司

以晋煤集团晋圣亿欣煤业XV1310回采工作面地表岩移观测站的建立为例,通过对该工作面地表岩移观测站的观测,获取了观测各期的下沉、水平移动、倾斜、曲率、水平变形值等数据,通过数据分析获得XV1310工作面开采过程中的动态沉陷规律、详... 详细信息

以晋煤集团晋圣亿欣煤业XV1310回采工作面地表岩移观测站的建立为例,通过对该工作面地表岩移观测站的观测,获取了观测各期的下沉、水平移动、倾斜、曲率、水平变形值等数据,通过数据分析获得XV1310工作面开采过程中的动态沉陷规律、详细的地表移动时间过程及15#煤层岩层移动参数,可指导该矿区进行“三下”开采和保护煤柱的留设。

关键词： XV1310工作面地表岩移观测站地表移动规律