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On the Largest Eigenvalue of Signless Laplacian Matrix of a Graph

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Journal of Mathematical Research and Exposition 2009年第3期29卷 381-390页

作者： TAN shang Wang WANG xing ke Department of Applied Mathematics China University of Petroleum Shandong 257061 China

The signless Laplacian matrix of a graph is the sum of its diagonal matrix of vertex degrees and its adjacency matrix. Li and Feng gave some basic results on the largest eigenvalue and characteristic polynomial of adjacency matrix of a graph in 1979. In this paper, we translate these results into the signless Laplacian matrix of a graph and obtain the similar results.

关键词： signless Laplacian matrix characteristic polynomial largest eigenvalue

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医院人才队伍建设的思考及意见

甘肃中医 2011年第4期24卷 72-73页

作者：杨廉洁尚兴科湖北医药学院附属太和医院湖北十堰442000

医院人才队伍的建设有利于医院保持活力,长远发展,提高竞争力。而加大人才培养力度、引入人才、做好人才配置工作、完善人才职称评审制度、完善育人机制改革等相关人才队伍建设等是医院人才队伍建设中不可缺少的有效措施。

关键词：医院卫生人才管理人才建设

表面结构与溶液离子对黑钨矿浮选影响的研究现状

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中国钨业 2015年第2期30卷 31-35页

作者：尚兴科蓝卓越周晓彤陈海亮昆明理工大学国土资源工程学院云南昆明650093 广州有色金属研究院广东广州510651

黑钨细泥采用重选法回收指标不理想,为提高黑钨细泥的回收利用率,对黑钨矿浮选进行了大量的深入研究。介绍了黑钨矿表面结构和溶液离子对黑钨矿浮选影响的研究现状,黑钨矿组成独特,其表面结构和化学组成存在较大差别。锰铁比不同的黑钨... 详细信息

黑钨细泥采用重选法回收指标不理想,为提高黑钨细泥的回收利用率,对黑钨矿浮选进行了大量的深入研究。介绍了黑钨矿表面结构和溶液离子对黑钨矿浮选影响的研究现状,黑钨矿组成独特,其表面结构和化学组成存在较大差别。锰铁比不同的黑钨矿,其可浮性存在差异,与药剂作用机理相当复杂,不同药剂的作用机理不尽相同。溶液离子来源广泛,对浮选过程具有较大影响,可活化矿物促进药剂在其表面的吸附,抑制矿物减弱药剂在其表面的吸附,与浮选药剂相互作用而消耗药剂。因此,研究黑钨矿表面结构特性以及溶液离子的影响有助于精准化控制黑钨浮选条件。

关键词：黑钨矿浮选表面结构溶液离子

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湖南某多金属矿钨锡同步浮选回收试验研究

矿冶工程 2022年第2期42卷 66-69页

作者：付广钦周晓彤邓丽红赵刚尚兴科广东省科学院资源利用与稀土开发研究所广东广州510650 稀有金属分离与综合利用国家重点实验室广东广州510650 广东省矿产资源开发和综合利用重点实验室广东广州510650

针对湖南某大型钨多金属矿有用矿物嵌布粒度细、矿物组成复杂、伴生锡资源品位低、矿物可浮性差、单独回收锡成本高等难题,在磨矿细度-0.074 mm粒级占82.35%条件下,采用自主研发的新型捕收剂GYX对WO_(3)品位0.34%、Sn品位0.089%的硫化... 详细信息

针对湖南某大型钨多金属矿有用矿物嵌布粒度细、矿物组成复杂、伴生锡资源品位低、矿物可浮性差、单独回收锡成本高等难题,在磨矿细度-0.074 mm粒级占82.35%条件下,采用自主研发的新型捕收剂GYX对WO_(3)品位0.34%、Sn品位0.089%的硫化矿浮选尾矿进行了1次粗选、3次扫选、5次精选的钨锡混合浮选,获得了WO_(3)品位38.11%、Sn品位3.87%的钨锡混合精矿,钨、锡回收率分别为74.05%、29.74%,实现了对钨锡矿物的同步回收。

关键词：浮选多金属矿钨锡混合浮选 GYX药剂钨锡

Evolution of gastrointestinal double contrast radiography in China:researches,application and popularization

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World Journal of Gastroenterology 1998年第3期4卷 17-21页

作者： shang ke-Zhong Department of Radiology Shanghai Sixth People's Hospital Shanghai 200233 China Department of Radiology Shanghai Second Medical University Acad. Comm. Chinese Gastrointest. R. China Department of Radiology Shanghai Sixth People's Hospital Shanghai 200233 600 Yishan Rd China

ＥｖｏｌｕｔｉｏｎｏｆｇａｓｔｒｏｉｎｔｅｓｔｉｎａｌｄｏｕｂｌｅｃｏｎｔｒａｓｔｒａｄｉｏｇｒａｐｈｙｉｎＣｈｉｎａ：ｒｅｓｅａｒｃｈｅｓ，ａｐｐｌｉｃａｔｉｏｎａｎｄｐｏｐｕｌａｒｉｚａｔｉｏｎＳＨＡＮＧＫｅ－Ｚ... 详细信息

ＥｖｏｌｕｔｉｏｎｏｆｇａｓｔｒｏｉｎｔｅｓｔｉｎａｌｄｏｕｂｌｅｃｏｎｔｒａｓｔｒａｄｉｏｇｒａｐｈｙｉｎＣｈｉｎａ：ｒｅｓｅａｒｃｈｅｓ，ａｐｐｌｉｃａｔｉｏｎａｎｄｐｏｐｕｌａｒｉｚａｔｉｏｎＳＨＡＮＧＫｅ－Ｚｈｏｎｇｕｂｊｅｃｔｈｅａｄｉｎｇ...

关键词： gastrointestinal diseases/radiotherapy barium/diagnostic use contrast media

Review on Security Defense Technology Research in Edge Computing Environment

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Chinese Journal of Electronics 2024年第1期33卷 1-18页

作者： ke shang Weizhen HE Shuai ZHANG National Digital Switching System Engineering and Technological R&D Center

Edge computing, which achieves quick data processing by sinking data computing and storage to the network edge, has grown rapidly along with the Internet of things. The new network architecture of edge computing brings new security challenges. Based on this, this paper investigates the edge computing security literature published in recent years and summarizes and analyzes research work on edge computing security from different attack surfaces. We start with the definition and architecture of edge computing. From the attack surface between device and edge server, as well as on edge servers, the research describes the security threats and defense methods of edge computing. In addition, the cause of the attack and the pros and cons of defense methods is introduced. The challenges and future research directions of edge computing are given.

关键词： Cloud computing Systems architecture Computer architecture Network architecture Data processing Security Servers

Impact of the Political Risk on Food Reserve Ratio:Evidence Across Countries

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Journal of Systems Science & Complexity 2024年第5期37卷 2071-2103页

作者： xing Kai LI shang YANG Xiaoguang School of Economics&Management Nanchang UniversityNanchang330031China Department of Statistics and Data Science National University of Singapore119077Singapore Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100190China

Using an unbalanced panel data covering 75 countries from 1991 to 2019,the authors explore how the political risk impacts on food reserve *** empirical findings show that an increasing political risk negatively affects food reserve ratio,and the same effects hold for both internal risk and external ***,the authors find that the increasing external or internal risks both negatively affect food production and food exports,but external risk does not significantly impact food imports and it positively impacts food consumption,while internal risk negatively impacts food imports and food *** results suggest that most governments have difficulty raising subsequent food reserve ratios in face of an increasing political risk,no matter if it is an internal risk or an external risk although the mechanisms behind the impacts are different.

关键词： External risk food reserve ratio internal risk political risk

Celastrol inhibits laser-induced choroidal neovascularization by decreasing VEGF induced proliferation and migration

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International Journal of Ophthalmology(English edition) 2022年第8期15卷 1221-1230页

作者： Zhen Li ke-Wen Zhou Fang Chen Fu shang Ming-xing Wu State key Laboratory of Ophthalmology Zhongshan Ophthalmic CenterSun Yat-sen UniversityGuangzhou 510060Guangdong ProvinceChina Department of Physiology Zhongshan School of MedicineSun Yat-sen UniversityGuangzhou 510080Guangdong ProvinceChina

AIM:To evaluate celastrol's effect on choroidal neovascularization(CNV).METHODS:In this study,neovascular formation in vitro(tube formation and aortic ring culture)and in vivo(laser induced neovascular in mice)was treated with celastrol to evaluate this natural compound's impact on *** blot was applied to explore the possible mechanism for *** in vitro assay,triplicate for each group was repeated at least three *** in vivo assay,each group contains 5 ***:Celastrol supressed tube formation and aortic ring sprout *** vitro assay exhibited that celastrol inhibiting vascular endothelial growth factor(VEGF)-induced proliferation and migration of human umbilical vein endothelial cells and human choroidal endothelial cells,and by blocking VEGF ***,intraperitoneal administration of celastrol significantly reduced the area of laser-induced CNV in an in vivo mouse *** day 14,the area of CNV had decreased by 49.15%and 80.26%in the 0.1 mg/kg celastrol-treated group(n=5)and in the 0.5 mg/kg celastrol treated group(n=5),respectively,compared to the vehicle-treated group(n=5).CONCLUSION:Celastrol inhibits CNV by inhibiting VEGF-induced proliferation and migration of vascular endothelial cells,indicating that celastrol is a potent,natural therapeutic compound for the prevention of CNV.

关键词： celastrol choroidal neovascularization proliferation vascular endothelial growth factor human choroidal endothelial cells

A novel signal feature extraction technology based on empirical wavelet transform and reverse dispersion entropy

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Defence Technology（防务技术） 2021年第5期17卷 1625-1635页

作者： Yu-xing Li shang-bin Jiao Xiang Gao School of Automation and Information Engineering Xi’an University of TechnologyXi’an710048China School of Electrical Engineering Xi’an University of TechnologyXi’an710048China

Feature extraction is an important part of signal processing,which is significant for signal detection,classification,and *** nonlinear dynamic analysis method can extract the nonlinear characteristics of signals and is widely used in different *** dispersion entropy(RDE)proposed by us recently,as a nonlinear dynamic analysis method,has the advantages of fast computing speed and strong anti-noise ability,which is more suitable for measuring the complexity of signal than traditional permutation entropy(PE)and dispersion entropy(DE).Empirical wavelet transform(EWT),based on the theory of wavelet analysis,can decompose a complex non-stationary signal into a number of empirical wavelet functions(EWFs)with compact support set spectrum,which has better decomposition performance than empirical mode decomposition(EMD)and its improved *** the advantages of RDE and EWT,on the one hand,we introduce EWT into the field of underwater acoustic signal processing and fault diagnosis to improve the signal decomposition accuracy;on the other hand,we use RDE as the features of EWFs to improve the signal separability and ***,we propose a novel signal feature extraction technology based on EWT and RDE in this *** results show that the proposed feature extraction technology can effectively extract the complexity features of actual ***,it also has higher distinguishing ability for different types of signals than five latest feature extraction technologies.

关键词： Feature extraction Empirical mode decomposition Empirical wavelet transform Permutation entropy Reverse dispersion entropy