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Energy Efficiency Analysis of Multi-Antenna Cellular Networks with Strategic Sleep Relay

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China Communications 2018年第9期15卷 136-146页

作者： yonghong chen Jie Yang Xuehong Cao Shibing Zhang Department of Communication and Information Engineering Nanjing University of Posts and Telecommunications Xinglin College Nantong University Department of Communication Engineering Nanjing Institute of Technology School of Electronics and Information Nantong University

Energy efficiency(EE) of cellular networks has attracted considerable attention recently. However, EE of relay-assisted cellular networks where the macro base stations(MBSs) are equipped with the multi-antenna has not been thoroughly addressed. This paper considered the downlink transmission of multi-antenna relay-assisted cellular networks, meanwhile, a strategic sleep scheme was used in relay stations(RSs), which dynamically adjusted the RS working mode according to whether the number of users serviced by the relay exceeds a given threshold. A geometric model was built to derive the coverage probability and mean achievable rate from the MBSs to user(UE), the MBS to RS, the RS to UE links and analyze the system EE. It is shown that the energy efficiency of cellular network with strategic sleep RS is slightly higher than that of cellular network with non-sleeping strategy. Furthermore, the MBS equipped with multi-antenna has better impact on energy efficiency and spectral efficiency than the MBS with single antenna.

关键词： energy efficiency coverage probability strategic sleep multi-antenna meana chievable rate

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黄金检测技术发展历程与展望

黄金 2024年第5期45卷 99-102页

作者：张雨陈永红柳华丽长春黄金研究院有限公司国家金银及制品质量检验检测中心(长春)

随着科学技术的不断发展,中国黄金检测技术得到了大幅提升。从黄金检测的历史、标准化道路、质量保证、自动化智能化发展4个方面阐述了黄金检测技术的发展历程,并对黄金检测的未来发展方向进行了展望,以期为黄金检测技术的高质量发展提... 详细信息

随着科学技术的不断发展,中国黄金检测技术得到了大幅提升。从黄金检测的历史、标准化道路、质量保证、自动化智能化发展4个方面阐述了黄金检测技术的发展历程,并对黄金检测的未来发展方向进行了展望,以期为黄金检测技术的高质量发展提供参考。

关键词：黄金检测标准化质量保证智能装备自动化

“一带一路”沿线建筑业全要素生产率的时空差异及空间效应

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工程管理学报 2024年第5期38卷 1-6页

作者：陈永鸿雷雯心荀梦娜昆明理工大学建筑工程学院云南昆明650500

运用DEA-Malmquist指数法对“一带一路”沿线省域建筑业全要素生产率进行测度和分析,构建空间计量模型进行实证研究。结果表明,“一带一路”沿线建筑业全要素生产率整体呈S型变化趋势,但不同地区间差异显著,丝绸之路经济带核心区、战略... 详细信息

运用DEA-Malmquist指数法对“一带一路”沿线省域建筑业全要素生产率进行测度和分析,构建空间计量模型进行实证研究。结果表明,“一带一路”沿线建筑业全要素生产率整体呈S型变化趋势,但不同地区间差异显著,丝绸之路经济带核心区、战略支点区明显高于对外窗口区和开放先行区。此外,地区经济发展水平、人力资本、科技水平、对外开放水平、产业结构和产业规模对沿线建筑业全要素生产率的提升具有不同的影响效应,推动建筑业转型升级是当前所面临的主要问题。研究旨在为新时期建筑业高质量发展和“一带一路”倡议的实施提供参考。

关键词： “一带一路” 建筑业全要素生产率空间计量

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定向运动体验式教学对大学生职业规划的启示

体育科技 2024年第3期45卷 116-118,121页

作者：陈永洪何树群沈建峰阿坝师范学院四川阿坝623002 四川师范大学四川成都610101

当前大学生对职业规划的意识、认知和理解等方面并不理想;基于此现状,研究试图通过《定向运动》课程体验式教学提供有效的思路与启示,促进学生对职业规划理解与认识,帮助学生在大学期间树立好自己的人身目标与规划:在体验式教学过程中,... 详细信息

当前大学生对职业规划的意识、认知和理解等方面并不理想;基于此现状,研究试图通过《定向运动》课程体验式教学提供有效的思路与启示,促进学生对职业规划理解与认识,帮助学生在大学期间树立好自己的人身目标与规划:在体验式教学过程中,让学生亲自感受《定向运动》教学内容中的地图识别、指北针运用、目标点的规划以及路线选择等过程,启发学生在职业规划过程中需要注意了解自己的基本情况,运用所学的知识,帮助自己树立人身目标,最后选择合理的路线到达自己的想要的目标点的一个过程。

关键词：定向运动职业规划大学生启示

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Synthesis of Fe3O4,Fe2O3,Ag/Fe3O4 and Ag/Fe2O3 nanoparticles and their electrocatalytic properties

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Science China Chemistry 2013年第3期56卷 362-369页

作者： PAN Lu TANG Jing chen yonghong Department of Chemistry and Chemical Engineering Huainan Normal University Anhui Key Laboratory of Low Temperature Co-Fired Material Huainan Normal University

Two important iron oxides:Fe3O4 and Fe2O3,as well as Fe3O4 and Fe2O3 nanoparticles mingling with Ag were successfully synthesized via a hydrothermal *** samples were confirmed and characterized by X-ray diffraction(XRD),and X-ray photoelectron spectroscopy(XPS).The morphology of the samples was observed by transmission electron microscopy(TEM).The results indicated Fe3O4,Fe2O3,Ag/Fe3O4 and Ag/Fe2O3 samples all were nanoparticles with smaller *** samples were modified on a glassy carbon electrode and their elctrocatalytic properties for p-nitrophenol in a basic solution were *** results revealed all the samples showed enhanced catalytic performances by comparison with a bare glassy carbon ***,p-nitrophenol could be reduced at a lower peak potential or a higher peak current on a glassy carbon electrode modified with Ag/Fe3O4 or Ag/Fe2O3 composite nanoparticles.

关键词： Fe3O4 Fe2O3 Ag/Fe3O4 Ag/Fe2O3 electrocatalysis

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高频开关电源变换器的数字控制研究

通信电源技术 2024年第7期41卷 127-129页

作者：李柯杜凤婷高航陈勇红国营长虹机械厂广西桂林541002

随着电力电子技术的迅速发展和高频开关电源变换器在各类电子设备中应用的日益广泛,数字控制技术因其卓越的性能和高度的灵活性成为研究的热点。通过分析数字脉宽调制(Digital Pulse Width Modulation,DPWM)生成数字占空比信号时产生的... 详细信息

随着电力电子技术的迅速发展和高频开关电源变换器在各类电子设备中应用的日益广泛,数字控制技术因其卓越的性能和高度的灵活性成为研究的热点。通过分析数字脉宽调制(Digital Pulse Width Modulation,DPWM)生成数字占空比信号时产生的问题,引出将模拟控制信号转换成数字占空比信号存在的局限,进而基于Boost变换器提出一种类比例-微分(Proportional-Derivative,PD)的模糊逻辑控制器(Fuzzy Logic Controller,FLC)。该数字控制系统可以直接生成占空比信号而不会导致极限环振荡,并通过实验证明了设计的控制器的有效性。高频开关电源变换器的数字控制研究旨在为电力电子领域提供更加精确、灵活及高效的控制方案,进一步推动高频开关电源变换器技术的发展。

关键词：数字控制数字脉宽调制(DPWM) 高频开关电源变换器

Comments on 2018 CPCS guideline for diagnosis and treatment of syncopein children and adolescents

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Science Bulletin 2019年第5期64卷 291-292页

作者： Chunyan Tao Xueqin Liu Chunyu Zhang yonghong chen? Yaqian Huang? Department of Pediatrics Peking University First Hospital

Syncope is one kind of transient loss of consciousness,due to transient global cerebral *** is sometimes misunderstood with other causes of transient loss of consciousness,like epilepsy,metabolic disorders,head trauma,psychological factors,and so *** in children and adolescents is common and seriously impacts the quality of their ***,its pathogenesis,etiologies,diagnosis and management are *** studies on syncope attract great interest of pediatricians and great progress has been made in this interesting *** on the improvement achieved so far,Chinese Pediatric Cardiology Society(CPCS)successfully developed a guideline for the diagnosis and treatment of syncope in children and adolescents,which would greatly improve the level of clinical management of syncope.

关键词： Comments 2018 CPCS guideline children and adolescents

数字建造模式下建设项目组织能力要素特征分析

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项目管理技术 2024年第4期22卷 22-27页

作者：陈永鸿韦仕芳丁陈永骏昆明理工大学建筑工程学院云南昆明650500 云南省教育厅基础设施智能运维科技创新团队云南昆明650500

在数字建造模式下,传统组织的核心要素被重新定义。以现代信息技术为契机,对传统建筑业建设项目组织能力进行基础性再思考和根本性重构已成为急需解决的问题。通过文献梳理数字建造模式下建设项目组织能力概念和内涵,采用机器学习对建... 详细信息

在数字建造模式下,传统组织的核心要素被重新定义。以现代信息技术为契机,对传统建筑业建设项目组织能力进行基础性再思考和根本性重构已成为急需解决的问题。通过文献梳理数字建造模式下建设项目组织能力概念和内涵,采用机器学习对建设项目组织能力研究文献进行聚类分析,结合内容分析法识别建设项目组织能力维度。在此基础上,融合数字建造情境提出数字建造模式下建设项目组织能力要素结构,系统辨析其构成要素特征,对完善数字建造模式下建设项目组织能力体系研究具有重要意义。

关键词：数字建造建设项目组织能力内涵界定要素结构

Joint Beamforming and Time Switching Designs for Energy-Constrained Cognitive Two-Way Relay Networks

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China Communications 2020年第5期17卷 110-118页

作者： Meijuan Zhang Shibing Zhang Zhihua Bao Wei Wang Xiaoge Zhang yonghong chen School of Information Science and Technology Nantong UniversityNantong 226019China Nantong Research Institute for Advanced Communication Technology Nantong 226019China Xinglin College Nantong UniversityNantong 226019China

In this paper, we investigate a joint beamforming and time switching(TS) design for an energy-constrained cognitive two-way relay(TWR) network. In the network, the energy-constrained secondary user(SU) relay employs TS protocol to harvest energy from the signals sent by the circuit-powered primary user(PU) transmitter, and then exploits the harvested energy to perform information forwarding. Our aim is to maximize the sum rate of SUs under the constraints of the data rate of PU, the energy harvesting and the transmit power of the SU relay. To determine the beamforming matrix and TS ratio, we decouple the original non-convex problem into two subproblems which can be solved by semidefinite relaxation and successive convex optimization methods. Furthermore, we derive closed form expressions of the optimal solutions for each subproblem, which facilitates the design of a suboptimal iterative algorithm to handle the original sum rate maximization problem. Simulation results are presented to illustrate the effectiveness and superior performance of the proposed joint design against other conventional schemes in the literature.

关键词： cognitive networks two-way relay sum rate energy harvesting beamforming