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Efficient Power Control for UAV Based on Trajectory and Game Theory
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作者 Fadhil Mukhlif Ashraf Osman Ibrahim +2 位作者 Norafida Ithnin Roobaea Alroobaea Majed Alsafyani 《Computers, Materials & Continua》 SCIE EI 2023年第3期5589-5606,共18页
Due to the fact that network space is becoming more limited,the implementation of ultra-dense networks(UDNs)has the potential to enhance not only network coverage but also network throughput.Unmanned Aerial Vehicle(UA... Due to the fact that network space is becoming more limited,the implementation of ultra-dense networks(UDNs)has the potential to enhance not only network coverage but also network throughput.Unmanned Aerial Vehicle(UAV)communications have recently garnered a lot of attention due to the fact that they are extremely versatile and may be applied to a wide variety of contexts and purposes.A cognitive UAV is proposed as a solution for the Internet of Things ground terminal’s wireless nodes in this article.In the IoT system,the UAV is utilised not only to determine how the resources should be distributed but also to provide power to the wireless nodes.The quality of service(QoS)offered by the cognitive node was interpreted as a price-based utility function,which was demonstrated in the form of a non-cooperative game theory in order to maximise customers’net utility functions.An energyefficient non-cooperative game theory power allocation with pricing strategy abbreviated as(EE-NGPAP)is implemented in this study with two trajectories Spiral and Sigmoidal in order to facilitate effective power management in Internet of Things(IoT)wireless nodes.It has also been demonstrated,theoretically and by the use of simulations,that the Nash equilibrium does exist and that it is one of a kind.The proposed energy harvesting approach was shown,through simulations,to significantly reduce the typical amount of power thatwas sent.This is taken into consideration to agree with the objective of 5G networks.In order to converge to Nash Equilibrium(NE),the method that is advised only needs roughly 4 iterations,which makes it easier to utilise in the real world,where things aren’t always the same. 展开更多
关键词 UAV spiral&sigmoid trajectory DRONES IoT game theory energy efficiency 6G
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Energy Efficiency Maximization Strategy for Sink Node in SWIPT-Enabled Sensor-Cloud Based on Optimal Stopping Rules 被引量:2
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作者 Zhe Wang Lina Ge +2 位作者 Taoshen Li Guifen Zhang Min Wu 《China Communications》 SCIE CSCD 2021年第1期222-236,共15页
Leveraging energy harvesting abilities in wireless network devices has emerged as an effective way to prolong the lifetime of energy constrained systems.The system gains are usually optimized by designing resource all... Leveraging energy harvesting abilities in wireless network devices has emerged as an effective way to prolong the lifetime of energy constrained systems.The system gains are usually optimized by designing resource allocation algorithm appropriately.However,few works focus on the interaction that channel’s time-vary characters make the energy transfer inefficiently.To address this,we propose a novel system operation sequence for sensor-cloud system where the Sinks provide SWIPT for sensor nodes opportunistically during downlink phase and collect the data transmitted from sensor nodes in uplink phase.Then,the energy-efficiency maximization problem of the Sinks is presented by considering the time costs and energy consumption of channel detection.It is proved that the formulated problem is an optimal stopping process with optimal stopping rules.An optimal energy-efficiency(OEE)algorithm is designed to obtain the optimal stopping rules for SWIPT.Finally,the simulations are performed based on the OEE algorithm compared with the other two strategies to verify the effectiveness and gains in improving the system efficiency. 展开更多
关键词 sensor-cloud SWIPT optimal stopping theory energy efficiency channel quality
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Active Design Method of Tooth Profiles for Cycloid Drive Based on Meshing Efficiency
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作者 WANG Jian SU Deyu 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2019年第3期413-423,共11页
An active design method of tooth profiles for cycloid gears based on their meshing efficiency is proposed.This method takes the meshing efficiency as one of the design variables to determine the tooth profiles.The cal... An active design method of tooth profiles for cycloid gears based on their meshing efficiency is proposed.This method takes the meshing efficiency as one of the design variables to determine the tooth profiles.The calculation method for the meshing efficiency of planetary transmission is analyzed and the equation of the meshing efficiency is deduced.Relationships between the meshing efficiency,the radius of the pin wheel and the eccentric distance are revealed.The design constraint quations and the strength constraint quations are deduced.On the basis of this,a design procedure is laid out.Some examples using different input parameters are conducted to demonstrate the feasibility of the approach.A dynamic simulation of the rigid flexible coupling of cycloid gears is also presented.The results show that the proposed design method is more flexible to control the tooth profiles by changing the input values of the transmission efficiency. 展开更多
关键词 CYCLOID DRIVE TOOTH PROFILE ACTIVE design MESHING efficiency MESHING theory
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Application of k-person and k-task maximal efficiency assignment algorithm to water piping repair
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作者 Su-juan ZHENG Xiu-ming YU Li-qing CAO 《Water Science and Engineering》 EI CAS 2009年第2期98-104,共7页
Solving the absent assignment problem of the shortest time limit in a weighted bipartite graph with the minimal weighted k-matching algorithm is unsuitable for situations in which large numbers of problems need to be ... Solving the absent assignment problem of the shortest time limit in a weighted bipartite graph with the minimal weighted k-matching algorithm is unsuitable for situations in which large numbers of problems need to be addressed by large numbers of parties. This paper simplifies the algorithm of searching for the even alternating path that contains a maximal element using the minimal weighted k-matching theorem and intercept graph. A program for solving the maximal efficiency assignment problem was compiled. As a case study, the program was used to solve the assignment problem of water piping repair in the case of a large number of companies and broken pipes, and the validity of the program was verified. 展开更多
关键词 graph theory maximal efficiency assignment problem minimal weighted k-matching algorithm intercept graph even alternating path water piping repair
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Game Theory-Based IoT Efficient Power Control in Cognitive UAV
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作者 Fadhil Mukhlif Norafida Ithnin +2 位作者 Omar B.Abdulghafoor Faiz Alotaibi Nourah Saad Alotaibi 《Computers, Materials & Continua》 SCIE EI 2022年第7期1561-1578,共18页
With the help of network densification,network coverage as well as the throughput can be improved via ultra-dense networks(UDNs).In tandem,Unmanned Aerial Vehicle(UAV)communications have recently garnered much attenti... With the help of network densification,network coverage as well as the throughput can be improved via ultra-dense networks(UDNs).In tandem,Unmanned Aerial Vehicle(UAV)communications have recently garnered much attention because of their high agility as well as widespread applications.In this paper,a cognitive UAV is proposed for wireless nodes power pertaining to the IoT ground terminal.Further,the UAV is included in the IoT system as the source of power for the wireless nodes as well as for resource allocation.The quality of service(QoS)related to the cognitive node was considered as a utility function based on pricing scheme that was modelled as a non-cooperative game theory in order to maximise users’net utility function.Moreover,an energy efficiency non-cooperative game theory power allocation with pricing scheme(EE-NGPAP)is proposed to obtain an efficient power control within IoT wireless nodes.Further,uniqueness and existence of the Nash equilibrium have been demonstrated mathematically and through simulation.Simulation results show that the proposed energy harvest algorithm demonstrated considerable decrease in transmitted power consumption in terms of average power reduction,which is regarded to be apt with the 5Gnetworks’vision.Finally,the proposed algorithm requires around 4 iterations only to converge to NE which makes the algorithm more suitable in practical heterogeneous scenarios. 展开更多
关键词 UAV DRONES WSN IOT game theory energy efficiency 5G&B5G networks
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A Novel Paradigm and Standard for Efficient C2C E-Business Platform based on Multivariate Optimization Theory
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作者 Zaixia HAN 《International Journal of Technology Management》 2015年第8期81-83,共3页
In this paper, we design and create the novel multivariate optimization theory based approach for building the paradigm. From the seller, web sites, the external environment, the respect such as online trust building ... In this paper, we design and create the novel multivariate optimization theory based approach for building the paradigm. From the seller, web sites, the external environment, the respect such as online trust building credibility evaluation index system. To factors affecting online trust as input will trust composite scores as the output, and then, using BP neural network technology, from the perspective of buyers and build a C2C e-commerce trust evaluation model. The multivariate optimization theory helps us modify the current pattern to be more feasible and robust. In the near future, we have scheduled to polish the neural network part to obtain better performance. 展开更多
关键词 C2C E-BUSINESS MULTIVARIATE Optimization theory NEURAL Network efficiENT Pattern.
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The Efficient Market Theory and Mergers and Acquisitions (M&As) Puzzle: Evidence From Italy
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作者 Domenico Celenza Fabrizio Rossi 《Journal of Modern Accounting and Auditing》 2012年第11期1704-1711,共8页
The efficient market theory is a central point in finance. If the capital market is competitive, the investors cannot expect superior gains from their investment strategies with respect to the risk profile. Event stud... The efficient market theory is a central point in finance. If the capital market is competitive, the investors cannot expect superior gains from their investment strategies with respect to the risk profile. Event studies are an approach to verify the impact of the information on the stock prices. In an efficient market, stock prices should fully, promptly, and quickly capture all the information. Instead, the market shows phenomena of an under-reaction and over-reaction for both the short and the long run. The mergers and acquisitions (M&As) are examples of anomalies. Often, the bidder companies record the negative abnormal returns for both the short and the long run. In contrast to the efficient market theory, the empirical evidence shows that this phenomenon is widespread in all (or most of) the countries of the world. This work examines the long-run performance in M&As. For this purpose, 40 bidders were observed in Italy during the period of 1994-2008 among listed companies. The buy and hold abnormal returns (BHARs) methodology was used, with which it was possible to observe the returns for three years following the deal. 展开更多
关键词 efficient market theory mergers and acquisitions (M&As) portfolio choice investment decisions buyand hold abnormal returns (BHARs) long-run performance Italian stock market
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On the Maximum of Wind Power Efficiency
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作者 Gerhard Kramm Gary Sellhorst +3 位作者 Hannah K. Ross John Cooney Ralph Dlugi Nicole Mölders 《Journal of Power and Energy Engineering》 2016年第1期1-39,共39页
In our paper we demonstrate that the filtration equation used by Gorban’ et al. for determining the maximum efficiency of plane propellers of about 30 percent for free fluids plays no role in describing the flows in ... In our paper we demonstrate that the filtration equation used by Gorban’ et al. for determining the maximum efficiency of plane propellers of about 30 percent for free fluids plays no role in describing the flows in the atmospheric boundary layer (ABL) because the ABL is mainly governed by turbulent motions. We also demonstrate that the stream tube model customarily applied to derive the Rankine-Froude theorem must be corrected in the sense of Glauert to provide an appropriate value for the axial velocity at the rotor area. Including this correction leads to the Betz-Joukowsky limit, the maximum efficiency of 59.3 percent. Thus, Gorban’ et al.’s 30% value may be valid in water, but it has to be discarded for the atmosphere. We also show that Joukowsky’s constant circulation model leads to values of the maximum efficiency which are higher than the Betz-Jow-kowsky limit if the tip speed ratio is very low. Some of these values, however, have to be rejected for physical reasons. Based on Glauert’s optimum actuator disk, and the results of the blade-element analysis by Okulov and S&oslashrensen we also illustrate that the maximum efficiency of propeller-type wind turbines depends on tip-speed ratio and the number of blades. 展开更多
关键词 Wind Power Power efficiency General Momentum theory Axial Momentum theory Blade Element Analysis Betz-Joukowsky Limit Joukowsky’s Constant Circulation Model Glauert’s Optimum Actuator Disk Balance Equation for Momentum Equation of Continuity Balance Equation for Kinetic Energy Reynolds’ Average Hesselberg’s Average Favre’s Average Bernoulli’s Equation Integral Equations
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Dimensional Complexity and Algorithmic Efficiency
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作者 Alexander Odilon Ngu 《International Journal of Modern Nonlinear Theory and Application》 2022年第1期1-10,共10页
This paper uses the concept of algorithmic efficiency to present a unified theory of intelligence. Intelligence is defined informally, formally, and computationally. We introduce the concept of dimensional complexity ... This paper uses the concept of algorithmic efficiency to present a unified theory of intelligence. Intelligence is defined informally, formally, and computationally. We introduce the concept of dimensional complexity in algorithmic efficiency and deduce that an optimally efficient algorithm has zero time complexity, zero space complexity, and an infinite dimensional complexity. This algorithm is used to generate the number line. 展开更多
关键词 Symbolic Intelligence Dimensional Complexity Algorithmic efficiency Notational Unification Turing Complete Machine Unified theory
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高温高盐油藏化学驱提高采收率理论技术与矿场应用
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作者 曹绪龙 石静 +4 位作者 张磊 刘煜 巩锦程 张文龙 张娜 《油气地质与采收率》 CAS CSCD 北大核心 2024年第5期16-26,共11页
化学驱是提高采收率的重要方法之一,在油田高效开发中发挥了重要作用。基于中外化学驱技术的发展现状,针对高温高盐的苛刻油藏条件,系统总结了胜利油田化学驱提高采收率的理论技术。通过梳理胜利油田60a来化学驱技术从室内研究到矿场应... 化学驱是提高采收率的重要方法之一,在油田高效开发中发挥了重要作用。基于中外化学驱技术的发展现状,针对高温高盐的苛刻油藏条件,系统总结了胜利油田化学驱提高采收率的理论技术。通过梳理胜利油田60a来化学驱技术从室内研究到矿场应用所攻克的理论和技术难题,介绍了高温高盐油藏化学驱的发展历程。通过认识驱油剂之间以及驱油剂与原油之间的相互作用和构效关系,迭代创建了高温高盐油藏聚合物“黏弹并重扩波及”理论、表面活性剂“油剂相似富集、阴非加合增效”理论和黏弹性颗粒“变形调驱”理论,并攻关形成了具有胜利特色的高温高盐油藏聚合物驱技术、无碱二元复合驱技术和非均相复合驱技术,攻克了温度为85℃、矿化度为30000 mg/L的油藏大幅度提高采收率的难题,矿场实施的96个化学驱项目的年产油量连续20a占油田年产油量的11%以上。该系列技术为胜利油田产量稳定和可持续发展做出了重要贡献。 展开更多
关键词 化学驱 高温高盐油藏 提高采收率 理论技术 加合增效
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重症急性胰腺炎患者急救护理流程再造及应用效果
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作者 王鑫 崔嬿嬿 +1 位作者 赵丽丽 底瑞青 《黑龙江医学》 2024年第8期1009-1011,共3页
目的:探讨重症急性胰腺炎(severe acute pancreatitis,SAP)患者急救护理流程再造及应用效果。方法:选取2019年1月—2022年1月样本医院收治的94例SAP患者作为研究对象,将2019年1月—2020年6月样本医院收治的47例SAP患者设为对照组,将2020... 目的:探讨重症急性胰腺炎(severe acute pancreatitis,SAP)患者急救护理流程再造及应用效果。方法:选取2019年1月—2022年1月样本医院收治的94例SAP患者作为研究对象,将2019年1月—2020年6月样本医院收治的47例SAP患者设为对照组,将2020年7月—2021年12月应用基于流程再造理论重组院内SAP急救护理流程的47例SAP患者设为研究组,比较两组患者急救效率和救治结局。结果:研究组分诊时间、候诊时间和就诊时间均短于对照组,差异有统计学意义(t=12.743、9.136、7.075,P<0.05)。研究组再入院率低于对照组,差异有统计学意义(χ^(2)=4.424,P<0.05)。死亡率比较差异无统计学意义(χ^(2)=0.261,P>0.05)。研究组满意度评分高于对照组,差异有统计学意义(t=6.231,P<0.001)。结论:对SAP患者应用基于流程再造理论重组急救护理流程,可提高SAP急救效果,改善患者救治结局。 展开更多
关键词 重症急性胰腺炎 流程再造理论 急救护理流程 急救效率 救治结局
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数字金融对绿色经济效率的影响——基于“两山”理论的研究
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作者 倪琳 许芷鸥 梁雨 《江苏大学学报(社会科学版)》 2024年第5期56-71,114,共17页
数字金融对绿色经济效率有何作为是亟待探讨的热点问题。“两山”理论对于加快形成绿色发展方式,促进经济发展和环境保护双赢提供了指引。基于“两山”理论的数字金融对绿色经济效率的机理和实证研究表明:我国的绿色经济效率呈现从东部... 数字金融对绿色经济效率有何作为是亟待探讨的热点问题。“两山”理论对于加快形成绿色发展方式,促进经济发展和环境保护双赢提供了指引。基于“两山”理论的数字金融对绿色经济效率的机理和实证研究表明:我国的绿色经济效率呈现从东部向中、西部递减的特征;数字金融能够显著促进绿色经济效率的提升,这一结论在稳健性检验、内生性分析后依然成立,且这种提升效应存在区域异质性,数字金融对东部绿色经济效率的提升显著大于中部和西部;技术创新和产业结构升级是数字金融提升绿色经济效率的中介渠道;绿色经济效率存在显著的空间自相关性,数字金融的作用效果具有正向空间溢出效应,有助于提升邻地的绿色经济效率。 展开更多
关键词 “两山”理论 数字金融 绿色经济效率 中介效应 空间溢出效应
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供应链融资对营运资金管理效率的影响
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作者 徐鹿 孟雪 《技术与创新管理》 2024年第4期400-414,共15页
通过实证分析,探讨供应链融资对企业营运资金管理效率的影响,能够为企业降低融资成本、提高资金利用率提供策略建议,有助于推动企业高质量发展。选取2010—2022年制造业A股上市公司的面板数据,运用定量分析方法,从渠道管理视角出发,探... 通过实证分析,探讨供应链融资对企业营运资金管理效率的影响,能够为企业降低融资成本、提高资金利用率提供策略建议,有助于推动企业高质量发展。选取2010—2022年制造业A股上市公司的面板数据,运用定量分析方法,从渠道管理视角出发,探讨采购、生产、营销3个渠道下供应链融资水平对营运资金周转期的影响。实证结果表明,在采购渠道下,供应商信赖度与营运资金周转期呈负相关关系,而短期应付账款比例与营运资金周转期呈正相关关系;在生产渠道下,生产渠道资金占用水平和链内薪金占用水平对营运资金周转期均有负向影响;在营销渠道下,客户信用依赖度和短期应收账款比例与营运资金周转期均呈负相关关系。此外,从整体层面研究发现,供应链信用依赖度对营运资金周转期有负向影响,而供应链资金占用度对营运资金周转期有正向影响。因此,合理运用供应链融资,可以显著提高营运资金管理效率。通过进一步研究发现,产权性质、是否为高科技企业以及市场地位的异质性分析对于理解供应链融资对营运资金管理效率影响的作用效果具有重要意义。 展开更多
关键词 供应链融资 营运资本 营运资金管理 营运资金管理效率 渠道管理理论
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偏向性技术进步对中国农业全要素生产率增长的影响研究
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作者 杨万平 张琪 《商业经济与管理》 北大核心 2024年第7期52-66,共15页
基于Antonelli的技术一致性理论,设定资本、劳动和土地的三要素标准化CES生产函数,利用泰勒展开法和近似技术推导偏向性技术进步框架下ATFP(农业全要素生产率)增长模型,系统考察偏向性技术进步、偏向性要素配置与要素投入结构和要素效... 基于Antonelli的技术一致性理论,设定资本、劳动和土地的三要素标准化CES生产函数,利用泰勒展开法和近似技术推导偏向性技术进步框架下ATFP(农业全要素生产率)增长模型,系统考察偏向性技术进步、偏向性要素配置与要素投入结构和要素效率结构的协调一致性对中国ATFP增长的驱动机制;检验ATFP增长在时间和空间上的差异来源。研究发现:中国农业偏向性技术进步与要素投入结构和要素效率结构的协调一致性促进了ATFP增长率提升,且一致性程度逐渐加深,成为ATFP增长的主要源泉;土地效率增长率低下是ATFP增长损失及后期ATFP增长放缓的主要原因,若能破除土地效率扭曲,ATFP增长率将提高3.28%;要素效率增长效应差异是中国ATFP增长率地区差异的主要来源。 展开更多
关键词 偏向性技术进步 要素效率结构 技术一致性 多要素标准化CES生产函数 方差分解
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财政拨款项目仪器设备购置生命周期协同管理模式探讨
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作者 赵莹颖 李心雅 +2 位作者 陈岩 马嘉奇 范宝林 《中国卫生标准管理》 2024年第2期48-52,共5页
如何充分利用财政拨款项目资金,合理配置诊疗、科研等专业设备,在保障项目进度的同时,做好仪器设备选型、论证等调研分析工作,规范采购流程,提高财政拨款项目仪器设备购置工作质效,一直是困扰业界的主要问题。通过广泛调研发现财政拨款... 如何充分利用财政拨款项目资金,合理配置诊疗、科研等专业设备,在保障项目进度的同时,做好仪器设备选型、论证等调研分析工作,规范采购流程,提高财政拨款项目仪器设备购置工作质效,一直是困扰业界的主要问题。通过广泛调研发现财政拨款项目仪器设备购置工作中存在的具体问题包括采购制度不完善、采购流程不规范、可行性论证不充分、需求调研不充分、采购执行进度控制困难、安装就位验收困难。借鉴生命周期理论和协同管理理论,总结某口腔专科医院在国家财政专项仪器设备购置经验,构建生命周期分段式横纵向协同管理模式,解决配置不合理、采购不规范、项目进度慢的问题;探讨进一步提高国家财政拨款项目仪器设备购置工作质效,加强医院诊疗科研能力,全面提升医院高质量发展效能的科学方法。 展开更多
关键词 财政拨款项目 仪器设备购置 生命周期理论 协同管理模式 购置工作质效 医院高质量发展
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面向6G的信息论与信道编码 被引量:2
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作者 张华滋 王俊 童文 《移动通信》 2024年第5期94-98,共5页
6G需要支持更多元化的性能指标,包括更高的峰值和用户速率,同时需要以更低的功耗和芯片复杂度来实现。回顾了现有的信息论与编码方法,并以即将到来的6G标准化背景,展望信息论与信道编码未来的需求和发展趋势,包括与信道编码相关的6G KPI... 6G需要支持更多元化的性能指标,包括更高的峰值和用户速率,同时需要以更低的功耗和芯片复杂度来实现。回顾了现有的信息论与编码方法,并以即将到来的6G标准化背景,展望信息论与信道编码未来的需求和发展趋势,包括与信道编码相关的6G KPI,以及指导6G信道编码设计的几个基本折衷关系等。以此说明,对于未来的信息论和编码研究,理论与实践的努力都远未达到终点,许多与编码实现与产品化的重要问题值得更多的理论研究关注。 展开更多
关键词 6G 信息论 信道编码 高吞吐 面积效率 能量效率
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应用图论建模输电网的电力现货市场出清模型 被引量:1
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作者 王进 张粒子 +1 位作者 丛野 陈皓轩 《中国电机工程学报》 EI CSCD 北大核心 2024年第9期3429-3439,I0007,共12页
电力现货市场优化出清模型的难点是考虑安全约束的机组组合(security constrained unit commitment,SCUC)模型。构建一个好的SCUC模型以提升求解速度是长期以来的研究热点。随着省电力系统规模的不断发展,以及国内省间电力现货市场的运... 电力现货市场优化出清模型的难点是考虑安全约束的机组组合(security constrained unit commitment,SCUC)模型。构建一个好的SCUC模型以提升求解速度是长期以来的研究热点。随着省电力系统规模的不断发展,以及国内省间电力现货市场的运行,现货市场对于出清模型的求解效率需求更为突出。该文对机组组合模型的研究历程进行详细综述,总结提出机组运行出力约束、出力上限约束、爬坡约束强化建模的机组运行模型;基于图论在线性最优潮流计算中的应用,构建输电网的环流潮流计算模型并引入SCUC模型,最终构建了一套可进一步提升求解效率的电力现货市场出清模型。最后通过多个大规模算例的计算分析表明,所提模型在保证不损失求解精度的同时,可有效提升求解效率,且对于阻塞频发的电力系统,优越性更为明显。 展开更多
关键词 机组组合 图论 环流潮流计算模型 求解效率
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基于火积理论对热管传热效率最优化问题的讨论
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作者 秦兴宇 喻有理 +7 位作者 赵鼎熙 李修齐 李朝阳 蒋臣威 方爱平 冯俊 张修兴 王小力 《物理与工程》 2024年第3期157-163,共7页
本文基于火积理论研究了热管中的热传输效率的优化问题。本文首先对比了传统熵理论和火积理论在分析传热效率方面的应用,然后详细介绍了火积理论,包括其物理意义和作为工程优化函数的应用。通过COMSOL仿真实验,本文展示了火积理论在热... 本文基于火积理论研究了热管中的热传输效率的优化问题。本文首先对比了传统熵理论和火积理论在分析传热效率方面的应用,然后详细介绍了火积理论,包括其物理意义和作为工程优化函数的应用。通过COMSOL仿真实验,本文展示了火积理论在热管设计优化中的实际应用,验证了理论的正确性,并对比了温差和火积耗散率与热管外径、芯层厚度等多个参数的关系,为热管等传热模型研究及生产设计优化提供了新视角。 展开更多
关键词 火积理论 热管 热传输效率 仿真模拟
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以循证理论为指导的急救护理路径在急性脑梗死患者中的应用效果 被引量:1
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作者 陈丽琴 林英 林雪娇 《中外医学研究》 2024年第17期83-86,共4页
目的:探讨以循证理论为指导的急救护理路径在急性脑梗死(ACI)患者中的应用效果。方法:回顾性分析2020年4月—2022年3月福建中医药大学附属第二人民医院急诊科收治的96例ACI患者的临床资料,按照救护方法的不同分为两组,各48例。对照组实... 目的:探讨以循证理论为指导的急救护理路径在急性脑梗死(ACI)患者中的应用效果。方法:回顾性分析2020年4月—2022年3月福建中医药大学附属第二人民医院急诊科收治的96例ACI患者的临床资料,按照救护方法的不同分为两组,各48例。对照组实施常规急诊救护,观察组实施以循证理论为指导的急救护理路径,两组均持续随访3个月。对比两组救治效率、神经功能、日常生活能力及护理满意度。结果:观察组院前救治时间、入院至医嘱下达时间、检查用时、入院至开始静脉溶栓时间分别为(4.11±0.42)min、(4.33±1.02)min、(8.46±1.43)min、(48.71±9.44)min,均短于对照组的(5.51±0.44)min、(5.56±1.33)min、(10.65±2.23)min、(55.96±10.63)min,差异有统计学意义(P<0.05)。观察组救护后美国国家卫生研究院卒中量表(NIHSS)评分为(15.48±3.10)分,低于对照组的(20.06±3.41)分,日常生活能力指数量表(ADL)评分为(76.35±6.95)分,高于对照组的(68.78±6.44)分,差异有统计学意义(P<0.05)。观察组护理满意度为95.83%,高于对照组的83.33%,差异有统计学意义(P<0.05)。结论:以循证理论为指导的急救护理路径在急性脑梗死患者中具有较好的救治效率,可改善神经功能及日常生活能力,提升护理满意度。 展开更多
关键词 急性脑梗死 急救护理路径 循证理论 救治效率 神经功能 护理满意度
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航天器表面材料紫外光电子发射产额理论模型发展及实验测试应用
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作者 辛文龙 侯潇涵 +4 位作者 于钱 沈自才 郭雅丽 彭吉龙 陈玉 《航空材料学报》 CAS CSCD 北大核心 2024年第3期23-34,共12页
空间环境会对航天器在轨效能发挥产生强烈影响,紫外(ultraviolet,UV)辐射是其中的一个重要因素,它可以导致航天器表面材料的电荷积累和电荷放电。通过测量航天器表面材料的紫外光电子发射产额(photoelectron emission yield,PEEY),获得... 空间环境会对航天器在轨效能发挥产生强烈影响,紫外(ultraviolet,UV)辐射是其中的一个重要因素,它可以导致航天器表面材料的电荷积累和电荷放电。通过测量航天器表面材料的紫外光电子发射产额(photoelectron emission yield,PEEY),获得光电发射基本数据,进行表面带电仿真分析,是研究航天器表面材料带电问题的一个重要方法。本文首先介绍PEEY理论模型的发展,包括福勒-杜布里奇(Fowler-Dubridge,FD)模型、一步模型、基于三步光电发射理论的三步模型(three-step model,TSM)/蒙特卡罗(Monte Carlo,MC)模型以及基于矩的(momentsbased,MB)发射模型和量子模型(quantum model,QM),对各个模型的研究方法和适用条件进行分析对比,梳理PEEY模型的发展脉络。然后介绍PEEY的实验测试应用,包括国内外紫外光电子产额谱(UV-PEEY)仪器的发展和典型空间材料的PEEY实验研究,并着重讨论外界条件和表面条件对PEEY的影响,最后对空间表面材料PEEY的深入研究提出建议。 展开更多
关键词 航天器表面材料 光电子发射产额 量子效率 三步发射理论 理论模型
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