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Dynamic Update Scheme of Spectrum Information Based on Spectrum Opportunity Incentive in the Database-Assisted Dynamic Spectrum Management
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作者 Zhang Yu Chen Yong +1 位作者 He Panfeng Cai Yueming 《China Communications》 SCIE CSCD 2024年第3期75-90,共16页
To solve the problem of delayed update of spectrum information(SI) in the database assisted dynamic spectrum management(DB-DSM), this paper studies a novel dynamic update scheme of SI in DB-DSM. Firstly, a dynamic upd... To solve the problem of delayed update of spectrum information(SI) in the database assisted dynamic spectrum management(DB-DSM), this paper studies a novel dynamic update scheme of SI in DB-DSM. Firstly, a dynamic update mechanism of SI based on spectrum opportunity incentive is established, in which spectrum users are encouraged to actively assist the database to update SI in real time. Secondly, the information update contribution(IUC) of spectrum opportunity is defined to describe the cost of accessing spectrum opportunity for heterogeneous spectrum users, and the profit of SI update obtained by the database from spectrum allocation. The process that the database determines the IUC of spectrum opportunity and spectrum user selects spectrum opportunity is mapped to a Hotelling model. Thirdly, the process of determining the IUC of spectrum opportunities is further modelled as a Stackelberg game by establishing multiple virtual spectrum resource providers(VSRPs) in the database. It is proved that there is a Nash Equilibrium in the game of determining the IUC of spectrum opportunities by VSRPs. Finally, an algorithm of determining the IUC based on a genetic algorithm is designed to achieve the optimal IUC. The-oretical analysis and simulation results show that the proposed method can quickly find the optimal solution of the IUC, and ensure that the spectrum resource provider can obtain the optimal profit of SI update. 展开更多
关键词 database-assisted dynamic spectrum management HOTELLING information updating contribution spectrum information updating STACKELBERG
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Evolutionary game dynamics of combining two different aspiration-driven update rules in structured populations
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作者 杨智昊 杨彦龙 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期182-191,共10页
In evolutionary games,most studies on finite populations have focused on a single updating mechanism.However,given the differences in individual cognition,individuals may change their strategies according to different... In evolutionary games,most studies on finite populations have focused on a single updating mechanism.However,given the differences in individual cognition,individuals may change their strategies according to different updating mechanisms.For this reason,we consider two different aspiration-driven updating mechanisms in structured populations:satisfied-stay unsatisfied shift(SSUS)and satisfied-cooperate unsatisfied defect(SCUD).To simulate the game player’s learning process,this paper improves the particle swarm optimization algorithm,which will be used to simulate the game player’s strategy selection,i.e.,population particle swarm optimization(PPSO)algorithms.We find that in the prisoner’s dilemma,the conditions that SSUS facilitates the evolution of cooperation do not enable cooperation to emerge.In contrast,SCUD conditions that promote the evolution of cooperation enable cooperation to emerge.In addition,the invasion of SCUD individuals helps promote cooperation among SSUS individuals.Simulated by the PPSO algorithm,the theoretical approximation results are found to be consistent with the trend of change in the simulation results. 展开更多
关键词 evolutionary game dynamics aspiration-driven update structured populations
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Snowfall Update
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作者 Maria Chiu 《空中英语教室(初级版.大家说英语)》 2024年第12期27-28,53,共3页
Julie:What are you looking at,Sam?Sam:Oh,hi,Julie.I'm looking at Fairview City's weekly snowfall update.Julie:But it's only Monday.Sam:I know.The update is for last week's snowfall.Julie:I see.It's... Julie:What are you looking at,Sam?Sam:Oh,hi,Julie.I'm looking at Fairview City's weekly snowfall update.Julie:But it's only Monday.Sam:I know.The update is for last week's snowfall.Julie:I see.It'sforthesecond weekofthis month,then.Sam:That's right.The datesare from December 8 to December 14. 展开更多
关键词 LOOKING update WEEKLY
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Searchable Encryption Cloud Storage with Dynamic Data Update to Support Efficient Policy Hiding 被引量:5
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作者 Laicheng Cao Yifan Kang +3 位作者 Qirui Wu Rong Wu Xian Guo Tao Feng 《China Communications》 SCIE CSCD 2020年第6期153-163,共11页
Ciphertext policy attribute based encryption(CP-ABE)can provide high finegrained access control for cloud storage.However,it needs to solve problems such as property privacy protection,ciphertext search and data updat... Ciphertext policy attribute based encryption(CP-ABE)can provide high finegrained access control for cloud storage.However,it needs to solve problems such as property privacy protection,ciphertext search and data update in the application process.Therefore,based on CP-ABE scheme,this paper proposes a dynamically updatable searchable encryption cloud storage(DUSECS)scheme.Using the characteristics of homomorphic encryption,the encrypted data is compared to achieve efficient hiding policy.Meanwhile,adopting linked list structure,the DUSECS scheme realizes the dynamic data update and integrity detection,and the search encryption against keyword guessing attacks is achieved by combining homomorphic encryption with aggregation algorithm.The analysis of security and performance shows that the scheme is secure and efficient. 展开更多
关键词 cloud storage dynamic update keywords search policy hidden
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Scoping review update on somatic symptom disorder that includes additional Chinese data 被引量:1
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作者 Heng Wu Ayinuer Manglike +3 位作者 Yixiao Chen Ziming Liu Kurt Fritzsche Zheng Lu 《General Psychiatry》 CSCD 2023年第3期198-213,共16页
Somatic symptom disorder(SSD)is a new diagnosis introduced into the Diagnostic and Statistical Manual of Mental Disorders,Fifth Edition(DSM-5),which is expected to solve the diagnostic difficulties of patients with me... Somatic symptom disorder(SSD)is a new diagnosis introduced into the Diagnostic and Statistical Manual of Mental Disorders,Fifth Edition(DSM-5),which is expected to solve the diagnostic difficulties of patients with medically unexplained symptoms.Based on the previous work,this review aims to comprehensively synthesise updated evidence related to SSD from recent years in English publications and,more extensively,from data published in Chinese language journals.The scoping review update was based on an earlier scoping review and included Chinese language publication data from China National Knowledge Internet(CNKI),WANFANG and WEIPU between January 2013 and May 2022 and data from PubMed,PsyclNFO,and Cochrane Library between June 2020 and May 2022.Initially,2984 articles were identified,of which 63 full texts were included for analysis.In China,SSD is mainly applied in scientific research,but it also shows good predictive validity and clinical application potential.The mean frequency of SSD was 4.5%in the general population,25.2%in the primary care population and 33.5%in diverse specialised care settings.Biological factors,such as brain region changes and heart rate variability,are associated with the onset of sSD.Psychological impairment related to somatic symptoms is the best predictor of prognosis.While adolescent SSD is significantly associated with family function,SSD overall is associated with an increased dysfunction of cognition and emotion,decreased quality of life,and high comorbidity with anxiety and depressive disorders.Further research is needed on suicide risk and cultural and gender-related issues.Updating the data of Chinese language studies,our research enriches the evidence-based findings related to the topics addressed in the text sections of the SSD chapter of DSM-5.However,research gaps remain about SSD reliability,population-based prevalence,suicide risk,and cultural and gender-related issues. 展开更多
关键词 include DIAGNOSIS update
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A Survey to View Update Problem
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作者 Hai-Tao Chen Hu-Sheng Liao 《Journal of Electronic Science and Technology》 CAS 2010年第4期318-327,共10页
Extensible markup language (XML) has become the de facto standard for representing and interchanging data in web-based applications. And XML view, a virtual window for specified users, has been widely applied. In pr... Extensible markup language (XML) has become the de facto standard for representing and interchanging data in web-based applications. And XML view, a virtual window for specified users, has been widely applied. In practical systems, users encounter the so-called view update problem when they need update source data through the view. For a long time, the view update problem is an open question in database community. With the development of various data models, the corresponding view update problem has been widely researched. In this paper, we introduce the conception of view update problem. We survey and compare previous approaches. Especially, we emphasize the role of semantics. Focusing on the problem in XML context, we give a discussion and propose a framework, which collects the semantic information at view definition time. Some related techniques for implementing this framework are further introduced. 展开更多
关键词 DATABASES SEMANTICS update VIEW XML.
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Optimization and Update of EAST In-Vessel Components in 2011
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作者 戢翔 宋云涛 +17 位作者 沈光 曹磊 周自波 许铁军 刘旭峰 徐薇薇 彭学兵 王声铭 张平 祝宁 戴羽 刘志宏 吴杰峰 高大明 龚先祖 傅鹏 万宝年 李建刚 《Plasma Science and Technology》 SCIE EI CAS CSCD 2013年第3期277-281,共5页
For safe operation with active water cooling plasma facing components (PFCs) to handle a large input power over a long pulse discharge, some design optimization, R&D and maintenance were accomplished to improve the... For safe operation with active water cooling plasma facing components (PFCs) to handle a large input power over a long pulse discharge, some design optimization, R&D and maintenance were accomplished to improve the in-vessel components. For the purpose of large plasma current (1 MA) operation, the previous separated top and bottom passive stabilizers in the low field were electrical connected to stabilize plasma in the case of vertical displace events (VDEs). The design and experiments are described in this paper 展开更多
关键词 EAST in-vessel component OPTIMIZATION update
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Secure Multi-keyword Search Supporting Dynamic Update and Ranked Retrieval
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作者 Jingbo Yan Yuqing Zhang Xuefeng Liu 《China Communications》 SCIE CSCD 2016年第10期209-221,共13页
As cloud computing is becoming prevalent, data owners are motivated to delegate complex data managements to the commercial cloud for economic savings. Sensitive data is usually encrypted before being uploaded to the c... As cloud computing is becoming prevalent, data owners are motivated to delegate complex data managements to the commercial cloud for economic savings. Sensitive data is usually encrypted before being uploaded to the cloud, which unfortunately makes the frequently-used search function a challenging problem. In this paper, we present a new multi-keyword dynamic search scheme with result ranking to make search over encrypted data more secure and practical. In the scheme, we employ a powerful function-hiding inner product encryption to enhance the security by preventing the leakage of search pattern. For the concern of efficiency, we adopt a tree-based index structure to facilitate the searching process and updating operations. A comprehensive security analysis is provided and experiments over the real world data show that our scheme is efficient. 展开更多
关键词 secure search ranked search dynamic update cloud computing
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Inference of interactions between players based on asynchronously updated evolutionary game data
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作者 曾红丽 景浡 +1 位作者 王于豪 秦绍萌 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第8期142-149,共8页
The interactions between players of the prisoner's dilemma game are inferred using observed game data.All participants play the game with their counterparts and gain corresponding rewards during each round of the ... The interactions between players of the prisoner's dilemma game are inferred using observed game data.All participants play the game with their counterparts and gain corresponding rewards during each round of the game.The strategies of each player are updated asynchronously during the game.Two inference methods of the interactions between players are derived with naive mean-field(n MF)approximation and maximum log-likelihood estimation(MLE),respectively.Two methods are tested numerically also for fully connected asymmetric Sherrington-Kirkpatrick models,varying the data length,asymmetric degree,payoff,and system noise(coupling strength).We find that the mean square error of reconstruction for the MLE method is inversely proportional to the data length and typically half(benefit from the extra information of update times)of that by n MF.Both methods are robust to the asymmetric degree but work better for large payoffs.Compared with MLE,n MF is more sensitive to the strength of couplings and prefers weak couplings. 展开更多
关键词 network reconstruction prisoner's dilemma game asynchronously update
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Median sternotomy closure:review and update research
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作者 Hua Kun Yang Xiubin 《Journal of Medical Colleges of PLA(China)》 CAS 2009年第2期112-117,共6页
Cardiac surgery is a very common operation nowadays all over the world.Median sternotomy is a routine procedure required for cardiac access during open heart surgery.The complications of this procedure after the cardi... Cardiac surgery is a very common operation nowadays all over the world.Median sternotomy is a routine procedure required for cardiac access during open heart surgery.The complications of this procedure after the cardiac surgery range from 0.7% to 1.5% of all cases,and bear a high mortality rate if they occur.Every individual surgeon must pay great attention on every detail during the sternal closure.This article shows the details as to conventional information and updated progress on median sternotomy closure.The update contents involve in biomechanics,number of wires twists,biomaterial and so on.According to our experience,we recommend four peristernal single/double steel wires for sternal closure as our optimal choice. 展开更多
关键词 Median stemotomy closure REVIEW update
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Update NOW!助我轻松上传网页
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作者 网天 《电子科技》 1999年第23期7-7,共1页
关键词 因特网 FTP软件 update NOWI软件 计算机网络
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Design Method Based on Routing Tree for Topology Update in Ad Hoc Network
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作者 魏正曦 张弘 王小玲 《Journal of Electronic Science and Technology of China》 2006年第2期106-109,共4页
A design method based on the tree-model structure for topology update is presented. The routing tree of every node in network is built by defining the data structure and is used to save the topology information of nei... A design method based on the tree-model structure for topology update is presented. The routing tree of every node in network is built by defining the data structure and is used to save the topology information of neighbor nodes. The node topology update is accomplished by exchanging their routing trees. For saving the precious wireless bandwidth, the routing tree is sparsely shaped before sending by pruning the redundant routing information. Then, the node topology update is implemented by using algorithms of inserting and deleting routing sub-trees. 展开更多
关键词 topology update sparse routing tree ALGORITHM ad hoc network
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UPDATES
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《China Textile》 2009年第3期6-8,共3页
CPI Grew Slightly in January Consumer price index(CPI) growth in January of 2009 was 1.0 percent over the same period of the previous year.Of which,urban area and rural area up by 0.7 and 1.5 percent respectively;the ... CPI Grew Slightly in January Consumer price index(CPI) growth in January of 2009 was 1.0 percent over the same period of the previous year.Of which,urban area and rural area up by 0.7 and 1.5 percent respectively;the price of foodstuff,consumable 展开更多
关键词 CPI updateS SOURCE DOWN NBS DESIGNER
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UPDATES
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《China Textile》 2008年第2期8-,12,共2页
Textile Exports may Drop Slightly in 2008The exports of China’s textile and garment will continue its double-digit growth in 2008, but with lower growth rate compared with 2007, according to Xu Kunyuan, the
关键词 CRI updateS OVER
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UPDATES
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《China Textile》 2008年第9期-,8+10+12+14,共5页
China’s Inflation to Continue Easing in August China’s consumer price index (CPI), a key measure of inflation, was expected to show a rise of about 5 percent in August from a year earlier, said analysts on Thursday.
关键词 CFCA updateS CPI
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UPDATES
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《China Textile》 2009年第2期6-,8+10,共3页
FDI Up by 23.58% in 2008 According to the statistics, from January to December 2008, foreign-invested enterprises newly approved for establishment reached
关键词 updateS SOURCE FDI
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Executive Cotton Update U.S. Macroeconomic Indicators & the Cotton Supply Chain
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《China Textile》 2017年第8期62-63,共2页
Macroeconomic Overview:The U.S.dollar has fallen 4%against a broad collection of widely circulated currencies since January.While the magnitude of the decline may not appear large,it does signal an important reversal ... Macroeconomic Overview:The U.S.dollar has fallen 4%against a broad collection of widely circulated currencies since January.While the magnitude of the decline may not appear large,it does signal an important reversal relative to recent years.Against the same broad collection of currencies,the U.S.dollar had consistently strengthened since 2013。 展开更多
关键词 Executive Cotton update U.S Macroeconomic Indicators the Cotton Supply Chain
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主页速传之“Update Now!2000”
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作者 陈彪 《电子与电脑》 2000年第12期100-102,共3页
新版的Update Now!2000是专为主页更新上传而设计的共享软件(图1),她能够识别修改和增加的文件,自动过滤旧文件,只上传新文件。目前,在Internet网上,绝大多数的主页存放空间提供商都支持通过FTP(文件传输协议)来维护更新主页。FT... 新版的Update Now!2000是专为主页更新上传而设计的共享软件(图1),她能够识别修改和增加的文件,自动过滤旧文件,只上传新文件。目前,在Internet网上,绝大多数的主页存放空间提供商都支持通过FTP(文件传输协议)来维护更新主页。FTP的客户端程序很多,常用的像Cuteftp,WS_FTP等等。通过这些程序可以实现主页的维护和更新。然而,这些FTP程序并不是为了主页维护而设计的,这些程序“体积”庞大,功能虽然很强,但是大部分的主页上传操作都需要用手工来完成,而新版的Update Now!2000则可以自动完成上传中的大多数工作。Update NOW!2000是纯32位的Windows应用程序,她需要在Windows95/98/2000以上版本的操作系统上运行。 展开更多
关键词 主页 文件传输协议 客户端程序 update Now!2000” 代理服务器
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Improvement of Update Mechanism for Object Management in High Level Architecture
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作者 FENG Yongxin FEI Shunchao +1 位作者 TIAN Minghao QIAN Bo 《沈阳理工大学学报》 CAS 2014年第2期81-87,共7页
As the distributed interactive simulation technology,the High Level Architecture(HLA)with the common Runtime Infrastructure(RTI)services has been applied to all kinds of simulation and computation areas,w hich has mor... As the distributed interactive simulation technology,the High Level Architecture(HLA)with the common Runtime Infrastructure(RTI)services has been applied to all kinds of simulation and computation areas,w hich has more interoperability and interactivity.Especially,w ith the development of hierarchical RTI softw are technology,the efficiency,flexibility,and levels of resolution etc.can be improved.How ever,updating mechanism for object management in hierarchical RTI can't supply the dynamic object subscription to the simulation operation,specially updating limitation in consistence and synchronization.Therefore,the improvement of update mechanism for object management has been proposed,and the process of w hich has been described.The results of simulation show that the improvement mechanism can achieve better updating rates and latency than traditional mechanism,considering the consistence need. 展开更多
关键词 High Level Architecture (HLA) RUNTIME INFRASTRUCTURE (RTI)
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基于非局部理论的Hoek-Brown软化塑性模型
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作者 周鑫 于佳佳 +2 位作者 吴文杰 路德春 杜修力 《防灾减灾工程学报》 北大核心 2025年第1期13-20,共8页
由于缺失材料特征长度,局部应变软化模型在模拟结构层面的失效破坏时,会出现网格依赖性问题,严重影响计算结果的准确性与可靠性。本研究提出了非局部的Hoek-Brown软化塑性模型,该模型基于光滑的Hoek-Brown强度准则构造屈服函数,并利用... 由于缺失材料特征长度,局部应变软化模型在模拟结构层面的失效破坏时,会出现网格依赖性问题,严重影响计算结果的准确性与可靠性。本研究提出了非局部的Hoek-Brown软化塑性模型,该模型基于光滑的Hoek-Brown强度准则构造屈服函数,并利用过非局部公式将等效塑性剪应变发展为非局部变量,有效规避了结构失效破坏模拟时的网格依赖性问题。利用隐式返回映射应力更新算法求解非局部塑性模型的微分方程组,详细介绍了该模型的有限元实现流程。最后,以经典的缺陷板受压破坏问题和条形基础承载力问题为例,对模型的有效性进行验证。结果表明,在网格细化过程中,非局部Hoek-Brown软化塑性模型的模拟结果对网格尺寸不敏感,预测的剪切带宽度和荷载位移曲线基本不随网格尺寸变化。所提模型可为岩石工程的失效破坏分析提供具有网格客观性的计算工具。 展开更多
关键词 非局部积分方法 软化塑性模型 HOEK-BROWN强度准则 应力更新算法
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