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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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An Updated Lagrangian Particle Hydrodynamics (ULPH)-NOSBPD Coupling Approach forModeling Fluid-Structure Interaction Problem
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作者 Zhen Wang Junsong Xiong +3 位作者 Shaofan Li Xin Lai Xiang Liu Lisheng Liu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期491-523,共33页
A fluid-structure interaction approach is proposed in this paper based onNon-Ordinary State-Based Peridynamics(NOSB-PD)and Updated Lagrangian Particle Hydrodynamics(ULPH)to simulate the fluid-structure interaction pro... A fluid-structure interaction approach is proposed in this paper based onNon-Ordinary State-Based Peridynamics(NOSB-PD)and Updated Lagrangian Particle Hydrodynamics(ULPH)to simulate the fluid-structure interaction problem with large geometric deformation and material failure and solve the fluid-structure interaction problem of Newtonian fluid.In the coupled framework,the NOSB-PD theory describes the deformation and fracture of the solid material structure.ULPH is applied to describe the flow of Newtonian fluids due to its advantages in computational accuracy.The framework utilizes the advantages of NOSB-PD theory for solving discontinuous problems and ULPH theory for solving fluid problems,with good computational stability and robustness.A fluidstructure coupling algorithm using pressure as the transmission medium is established to deal with the fluidstructure interface.The dynamic model of solid structure and the PD-ULPH fluid-structure interaction model involving large deformation are verified by numerical simulations.The results agree with the analytical solution,the available experimental data,and other numerical results.Thus,the accuracy and effectiveness of the proposed method in solving the fluid-structure interaction problem are demonstrated.The fluid-structure interactionmodel based on ULPH and NOSB-PD established in this paper provides a new idea for the numerical solution of fluidstructure interaction and a promising approach for engineering design and experimental prediction. 展开更多
关键词 Fluid-structure interaction(FSI) updated lagrangian particle hydrodynamics PERIDYNAMICS meshfree method
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Updated Lagrangian Particle Hydrodynamics (ULPH)Modeling of Natural Convection Problems
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作者 Junsong Xiong Zhen Wang +3 位作者 Shaofan Li Xin Lai Lisheng Liu Xiang Liu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期151-169,共19页
Natural convection is a heat transfer mechanism driven by temperature or density differences,leading to fluid motion without external influence.It occurs in various natural and engineering phenomena,influencing heat t... Natural convection is a heat transfer mechanism driven by temperature or density differences,leading to fluid motion without external influence.It occurs in various natural and engineering phenomena,influencing heat transfer,climate,and fluid mixing in industrial processes.This work aims to use the Updated Lagrangian Particle Hydrodynamics(ULPH)theory to address natural convection problems.The Navier-Stokes equation is discretized using second-order nonlocal differential operators,allowing a direct solution of the Laplace operator for temperature in the energy equation.Various numerical simulations,including cases such as natural convection in square cavities and two concentric cylinders,were conducted to validate the reliability of the model.The results demonstrate that the proposed model exhibits excellent accuracy and performance,providing a promising and effective numerical approach for natural convection problems. 展开更多
关键词 updated Lagrangian particle hydrodynamics(ULPH) natural convection meshless methods higher order Laplacian model
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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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架设局域网内的Update服务器
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作者 贾大江 宋晓涛 《山西电力》 2004年第4期64-65,共2页
越来越多的病毒利用微软操作系统的漏洞传播,及时给系统升级打补丁成了计算机管理的一项重要工作。在局域网内架设软件升级服务器,可以提高升级系统的效率。为计算机系统的安全运行提供保障。
关键词 局域网 update服务器 网络管理员 工作组
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BGP协议中UPDATE报文的并行化处理方法 被引量:2
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作者 丁利娜 王兴伟 +1 位作者 李福亮 黄敏 《小型微型计算机系统》 CSCD 北大核心 2016年第11期2459-2463,共5页
互联网的规模日益扩大,作为域间路由协议标准的BGP协议,其性能面临着前所未有的考验.而路由更新(UPDATE)报文仍采用串行化的方式来处理,处理速度慢,极大地影响了BGP协议的性能.为此,提出一种UPDATE报文的并行化处理方法来解决这个问题.... 互联网的规模日益扩大,作为域间路由协议标准的BGP协议,其性能面临着前所未有的考验.而路由更新(UPDATE)报文仍采用串行化的方式来处理,处理速度慢,极大地影响了BGP协议的性能.为此,提出一种UPDATE报文的并行化处理方法来解决这个问题.该方法采用流水线技术和多线程技术,能够提高UPDATE报文的处理速度.为了进一步提高该方法的效率,我们在UPDATE报文的并行化处理过程中引入了垃圾回收机制和多线程动态调节策略.最后,我们在Quagga原型系统上对该并行化处理方法进行了仿真实现,并与Quagga中原始的BGPD模块的测试结果进行了对比分析,实验结果表明,本文设计的UPDATE报文的并行化处理方法是可行且有效的. 展开更多
关键词 BGP协议 update报文 并行化处理 流水线 多线程
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基于TQuery与TUpdateQuery的多表缓冲更新技术
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作者 刘惊雷 《计算机工程》 CAS CSCD 北大核心 2004年第24期159-161,179,共4页
以C++Builder中的TQuery和TUpdatequery控件为例,阐述了进行现场数据的查询和缓冲更新的原理和技术,并解决了更新查询中的多个基表的问题。同时介绍了TDataSource控件的动态数据交换与验证的功能。最后在计算机上编制程序实现了以数据... 以C++Builder中的TQuery和TUpdatequery控件为例,阐述了进行现场数据的查询和缓冲更新的原理和技术,并解决了更新查询中的多个基表的问题。同时介绍了TDataSource控件的动态数据交换与验证的功能。最后在计算机上编制程序实现了以数据缓冲技术实现多表更新的问题。 展开更多
关键词 数据缓冲区 缓冲更新 多表更新 动态数据交换
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ORACLE游标中的多表UPDATE行锁讨论 被引量:3
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作者 张练兴 马明磊 《江西师范大学学报(自然科学版)》 CAS 北大核心 2005年第6期489-491,共3页
介绍了Oracle中的封锁机制,分析了共享更新封锁的特点,并就游标中的多表更新行锁以及怎样避免死锁错误进行了讨论.
关键词 ORACLE数据库 游标 多表update行锁
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云环境下基于XUpdate的XML更新研究
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作者 张涛 方少卿 《长春师范大学学报》 2018年第6期80-84,共5页
本文在研究XUpdate语言的基础上,构建了一种基于XUpdate的更新处理架构,面对云计算环境下大量的XML数据的管理,为更新XML文档提出了一种通用的模式和规范。
关键词 XML更新 Xupdate 云计算
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蠕虫“Update-Factor”传播模型研究
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作者 张殿旭 张怡 《计算机应用》 CSCD 北大核心 2008年第B06期66-70,共5页
双因素模型考虑了人为对抗因素和蠕虫传播对路由造成的冲击,较SI模型、SIS模型和KM模型更能符合蠕虫传播的实际情况。但它不能反映蠕虫传播后期的特性,同时模型没有考虑大规模系统升级程序和自动补丁程序这一重要的对抗因素对蠕虫传播... 双因素模型考虑了人为对抗因素和蠕虫传播对路由造成的冲击,较SI模型、SIS模型和KM模型更能符合蠕虫传播的实际情况。但它不能反映蠕虫传播后期的特性,同时模型没有考虑大规模系统升级程序和自动补丁程序这一重要的对抗因素对蠕虫传播的影响。针对双因素模型的不足,对其进行了改进,提出了"Update-Factor"模型,经仿真结果与实际监测结果比较,模型克服了双因素模型的不足,更符合蠕虫传播的实际情况。 展开更多
关键词 双因素模型 update-Factor模型 蠕虫传播模型
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利用TUpdateSQL组件实现数据缓存更新
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作者 刘卫 《计算机与现代化》 2006年第1期51-53,57,共4页
数据更新是数据库应用系统的一个重要组成部分。本文介绍在Delphi数据库应用程序中,利用TUpdateSQL组件实现基于BDE的缓存更新。
关键词 缓存更新 数据集 Tupdate SQL DELPHI
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如何在内联网上架设Windows Update服务器
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作者 石磊 《中国金融电脑》 2004年第7期57-58,共2页
关键词 内联网 互联网 物理隔离 WINDOWS update 服务器
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PB中数据窗口的Update Properties研究
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作者 胡顺义 史小松 《电脑知识与技术》 2009年第4Z期2875-2876,共2页
介绍了PB中数据窗口的Update Properties各项的含义和作用,利用这些属性可以设置数据窗口关联的数据库表是否能被更新、并发控制及键的更新方式,使得用户不仅懂得设置还知道其所以然。
关键词 PB 数据窗口 更新 并发控制
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Update on hepatocellular carcinoma: Pathologists' review 被引量:31
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作者 Tony El Jabbour Stephen M Lagana Hwajeong Lee 《World Journal of Gastroenterology》 SCIE CAS 2019年第14期1653-1665,共13页
Histopathologic diversity and several distinct histologic subtypes of hepatocellular carcinoma(HCC) are well-recognized. Recent advances in molecular pathology and growing knowledge about the biology associated with d... Histopathologic diversity and several distinct histologic subtypes of hepatocellular carcinoma(HCC) are well-recognized. Recent advances in molecular pathology and growing knowledge about the biology associated with distinct histologic features and immuno-profile in HCC allowed pathologists to update classifications. Improving sub-classification will allow for more clinically relevant diagnoses and may allow for stratification into biologically meaningful subgroups. Therefore, immuno-histochemical and molecular testing are not only diagnostically useful, but also are being incorporated as crucial components in predicting prognosis of the patients with HCC. Possibilities of targeted therapy are being explored in HCC, and it will be important for pathologists to provide any data that may be valuable from a theranostic perspective. Herein, we review and provide updates regarding the pathologic sub-classification of HCC.Pathologic diagnostic approach and the role of biomarkers as prognosticators are reviewed. Further, the histopathology of four particular subtypes of HCC:Steatohepatitic, clear cell, fibrolamellar and scirrhous-and their clinical relevance, and the recent consensus on combined HCC-cholangiocarcinoma is summarized. Finally, emerging novel biomarkers and new approaches to HCC stratification are reviewed. 展开更多
关键词 HEPATOCELLULAR CARCINOMA SUBTYPE Classification REVIEW update
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Update in management of hepatocellular carcinoma in Eastern population 被引量:8
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作者 Kevin Ka Wan Chu Tan To Cheung 《World Journal of Hepatology》 CAS 2015年第11期1562-1571,共10页
Hepatocellular carcinoma(HCC) is one of the commonest malignant tumours in the East. Although the management of HCC in the West is mainly based on the Barcelona Clinic for Liver Cancer staging, it is considered too co... Hepatocellular carcinoma(HCC) is one of the commonest malignant tumours in the East. Although the management of HCC in the West is mainly based on the Barcelona Clinic for Liver Cancer staging, it is considered too conservative by Asian countries where the number of HCC patients is huge. Scientific and clinical advances were made in aspects of diagnosis, staging, and treatment of HCC. HCC is well known to be associated with cirrhosis and the treatment of HCC must take into account the presence and stage of chronic liver disease. The major treatment modalities of HCC include:(1) surgical resection;(2) liver transplantation;(3) local ablation therapy;(4) transarterial locoregional treatment; and(5) systemic treatment. Among these, resection, liver transplantation and ablation therapy for small HCC are considered as curative treatment. Portal vein embolisation and the associating liver partition with portal vein ligation for staged hepatectomy may reduce dropout in patients with marginally resectable disease but the midterm and long-term results are still to be confirmed. Patient selection for the best treatment modality is the key to success of treatment of HCC. The purpose of current review is to provide a description of the current advances in diagnosis, staging, preoperative liver function assessment and treatment options for patients with HCC in the east. 展开更多
关键词 HEPATOCELLULAR carcinoma Liver CIRRHOSIS Treatment MANAGEMENT Evidence SURVIVAL update
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Realization of remote update technology for embedded equipment based on μC/OS-Ⅱ 被引量:2
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作者 孟辉 潘炼 《Journal of Measurement Science and Instrumentation》 CAS 2014年第3期69-72,共4页
Aiming at the inaccessible problem of remote embedded devices update and maintenance, this paper presents a method using general packet radio service (GPRS) to achieve update based on the embedded real-time operatin... Aiming at the inaccessible problem of remote embedded devices update and maintenance, this paper presents a method using general packet radio service (GPRS) to achieve update based on the embedded real-time operating system (RTOS) μC/OS-Ⅱ. It introduces architecture of the system first. And then it uses LPC1768 chip as the central processing unit, SIM900A module for data transmission, and SST25VF016B to store the data. To ensure accuracy of the data transmis- sion, cyclic redundancy code (CRC) is adopted. The software uses fixed bootstrap and mutable update program, and thus the embedded devices can still normally start in case of update failure. Finally, high stability and extensive adaptability of the system are verified by experimental data. 展开更多
关键词 μC/OS-ⅡμC/OS-ⅡμC/OS-Ⅱ remote update general packet radio service (GPRS) embedded system
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Use of Incremental Analysis Updates in 4D-Var Data Assimilation 被引量:4
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作者 Banglin ZHANG Vijay TALLAPRAGADA +2 位作者 Fuzhong WENG Jason SIPPEL Zaizhong MA 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2015年第12期1575-1582,共8页
The four-dimensional variational (4D-Var) data assimilation systems used in most operational and research centers use initial condition increments as control variables and adjust initial increments to find optimal a... The four-dimensional variational (4D-Var) data assimilation systems used in most operational and research centers use initial condition increments as control variables and adjust initial increments to find optimal analysis solutions. This approach may sometimes create discontinuities in analysis fields and produce undesirable spin ups and spin downs. This study explores using incremental analysis updates (IAU) in 4D-Var to reduce the analysis discontinuities. IAU-based 4D-Var has almost the same mathematical formula as conventional 4D-Var if the initial condition increments are replaced with time-integrated increments as control variables. The IAU technique was implemented in the NASA/GSFC 4D-Var prototype and compared against a control run without IAU. The results showed that the initial precipitation spikes were removed and that other discontinuities were also reduced, especially for the analysis of surface temperature. 展开更多
关键词 data assimilation incremental analysis updates 4D-Vat convergence
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Cancer statistics: updated cancer burden in China 被引量:146
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作者 Wanqing Chen 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2015年第1期1-1,共1页
Cancer is a major public health issue in most of countries, including China. Accurate and valid information on cancer incidence, mortality, survival and relevant factors is irreplaceable for cancer prevention and cont... Cancer is a major public health issue in most of countries, including China. Accurate and valid information on cancer incidence, mortality, survival and relevant factors is irreplaceable for cancer prevention and control. Since the national program of cancer registry was launched by the Ministry of Health of China in 2008, the National Central Cancer Registry (NCCR) has been releasing the cancer incidence and mortality based on the data collected from cancer registries supported by the program. The cancer statistics provide current data from registered areas and aims to accurately reflect the cancer burden and epidemic in China. In 2014, the NCCR collected data for calendar year 2011 from 234 registries. After comprehensive quality' evaluation, data from 177 registries have been selected as sources of the reports reflecting cancer incidence and mortaliD, in the registration areas in 2011. These reports are the updated cancer statistics so far, covering much more registries and a hig population. 展开更多
关键词 Cancer statistics updated cancer burden in China
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Model update mechanism for mean-shift tracking 被引量:3
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作者 PengNingsong YangJie LiuErqi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第1期52-57,共6页
In order to solve the model update problem in mean-shift based tracker, a novel mechanism is proposed. Kalman filter is employed to update object model by filtering object kernel-histogram using previous model and cur... In order to solve the model update problem in mean-shift based tracker, a novel mechanism is proposed. Kalman filter is employed to update object model by filtering object kernel-histogram using previous model and current candidate. A self-tuning method is used for adaptively adjust all the parameters of the filters under the analysis of the filtering residuals. In addition, hypothesis testing servers as the criterion for determining whether to accept filtering result. Therefore, the tracker has the ability to handle occlusion so as to avoid over-update. The experimental results show that our method can not only keep up with the object appearance and scale changes but also be robust to occlusion. 展开更多
关键词 MEAN-SHIFT TRACKING model update Kalman filter hypothesis testing.
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