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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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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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Updates in the Diagnosis of Gestational Trophoblast Disease
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作者 Maira de Lima Oliveira Mota Marcela Curvêllo Beltrão +7 位作者 Elizabeth Bacha Eduardo Fonseca Mascarenhas Filho Maísa Mendonça de Jesus Nelson Henriky Felix Mascarenhas Tallys Leandro Barbosa da Silva Maria Fernanda Telles Pires de Souza Victoria de Oliveira Carmo Borges Séfora Maria Fragoso Braga 《Health》 CAS 2023年第1期48-58,共11页
GTD (Gestational Trophoblastic Disease) is a pathology that encompasses benign and malignant clinical forms, affects women of childbearing age, has a variable incidence and is more frequent in developing or underdevel... GTD (Gestational Trophoblastic Disease) is a pathology that encompasses benign and malignant clinical forms, affects women of childbearing age, has a variable incidence and is more frequent in developing or underdeveloped countries, colliding with the economic barrier. The frequent absence of clear protocols and guidelines for the correct diagnosis of the pathology results in inadequate classification, imprecise treatment and failed post-therapeutic observation, increasing the risk of relapses, morbidity and mortality. The present study aims to point out updated national and international practice protocols of diagnosis of GTD, through an integrative review. Seven articles were selected and it was observed that the main international reference centers are agreed with the management suggested by the IFGO (International Federation of Gynecology and Obstetrics), being the conduct in the Hydatidiform Mole (HM): evacuation by suction and curettage under ultrasound guidance, followed by hCG monitoring every 1 - 2 weeks until normalized (usually one month for Partial Hydatidiform Mole six months for Complete Hydatidiform Mole and one year for Gestational Trophoblastic Neoplasia). Unfortunately, regarding the diagnosis of MH, the guidelines of some countries show the absence or difficulty of access to the karyotype test and ploid p57 or pelvic ultrasound accompanying the uterine curettage, contrary to what is proposed by the IFGO guideline. Establishing and complying with consistent guidelines can improve patient care, with early diagnosis of the pathology and its complications, reducing the rate of recurrence, morbidity and mortality, especially in less developed countries. 展开更多
关键词 DIAGNOSIS Gestational Trophoblastic Disease updateS
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基于改进UpdateNet的行人视觉跟踪算法
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作者 胡肖 焦立男 柳有权 《计算机与现代化》 2023年第5期80-85,共6页
目前,基于孪生网络的跟踪器主要是把跟踪过程看作是目标模板分支和待检测区域分支的一种互相关计算,它能够在速度和精度方面达到一个良好的均衡。然而,在跟踪过程中当前帧模板是对前一帧累积模板的线性结合,目标遮挡的问题一直很难被解... 目前,基于孪生网络的跟踪器主要是把跟踪过程看作是目标模板分支和待检测区域分支的一种互相关计算,它能够在速度和精度方面达到一个良好的均衡。然而,在跟踪过程中当前帧模板是对前一帧累积模板的线性结合,目标遮挡的问题一直很难被解决。针对该问题,本文采用改进SiamRPN跟踪器并融合UpdateNet网络的方案实现对行人单目标的跟踪。首先利用改进SiamRPN网络模块生成线性模板,然后在此基础上融合UpdateNet网络生成更新模板并进行多阶段训练,最后根据数据集的评价指标选取最优参数模型完成行人跟踪任务。本文在基准数据集OTB2015和其子集上进行实验,实验结果表明,本文所采用的方法取得的效果相比原来方法有明显提升,精度和成功率分别提高2.1和1.6个百分点,而且保持了实时跟踪帧率,同时在解决遮挡问题方面超过了DaSiamRPN、SiamDW等先进方法. 展开更多
关键词 孪生网络 updateNet网络 更新模板 目标遮挡 行人单目标
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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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Health Data Availability Protection:Delta-XOR-Relay Data Update in Erasure-Coded Cloud Storage Systems
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作者 Yifei Xiao Shijie Zhou 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第4期169-185,共17页
To achieve the high availability of health data in erasure-coded cloud storage systems,the data update performance in erasure coding should be continuously optimized.However,the data update performance is often bottle... To achieve the high availability of health data in erasure-coded cloud storage systems,the data update performance in erasure coding should be continuously optimized.However,the data update performance is often bottlenecked by the constrained cross-rack bandwidth.Various techniques have been proposed in the literature to improve network bandwidth efficiency,including delta transmission,relay,and batch update.These techniques were largely proposed individually previously,and in this work,we seek to use them jointly.To mitigate the cross-rack update traffic,we propose DXR-DU which builds on four valuable techniques:(i)delta transmission,(ii)XOR-based data update,(iii)relay,and(iv)batch update.Meanwhile,we offer two selective update approaches:1)data-deltabased update,and 2)parity-delta-based update.The proposed DXR-DU is evaluated via trace-driven local testbed experiments.Comprehensive experiments show that DXR-DU can significantly improve data update throughput while mitigating the cross-rack update traffic. 展开更多
关键词 Data availability health data data update cloud storage IoT
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System Reliability Analysis for Truss Structures Based on Automatic Updated Model
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作者 Pengyu Chen Cunbao Zhao +1 位作者 He Yao Junliang Li 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第3期2057-2071,共15页
Multiple failure modes tend to be identified in the reliability analysis of a redundant truss structure.This identification process involves updating the model for identifying the next potential failure members.Herein... Multiple failure modes tend to be identified in the reliability analysis of a redundant truss structure.This identification process involves updating the model for identifying the next potential failure members.Herein we intend to update the finite element model automatically in the identification process of failure modes and further perform the system reliability analysis efficiently.This study presents a framework that is implemented through the joint simulation of MATLAB and APDL and consists of three parts:reliability index of a single member,identification of dominant failure modes,and system-level reliability analysis for system reliability analysis of truss structures.Firstly,RSM(response surface method)combines with a constrained optimization model to calculate the reliability indices ofmembers.Then theβ-unzipping method is adopted to identify the dominant failuremodes,and the system function in MATLAB,as well as the EKILL command in APDL,is used to facilitate the automatic update of the finite element model and realize load-redistribution.Besides,the differential equivalence recursion algorithmis performed to approximate the reliability indices of failuremodes efficiently and accurately.Eventually,the PNET(probabilistic network evaluation technique)is used to calculate the joint failure probability as well as the system reliability index.Two illustrative examples demonstrate the accuracy and efficiency of the proposed system reliability analysis framework through comparison with corresponding references. 展开更多
关键词 Multiple failure modes truss structure automatic update system reliability analysis framework
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Fast Verification of Network Configuration Updates
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作者 Jiangyuan Yao Zheng Jiang +5 位作者 Kaiwen Zou Shuhua Weng Yaxin Li Deshun Li Yahui Li Xingcan Cao 《Computers, Materials & Continua》 SCIE EI 2023年第1期293-311,共19页
With the expansion of network services,large-scale networks have progressively become common.The network status changes rapidly in response to customer needs and configuration changes,so network configuration changes ... With the expansion of network services,large-scale networks have progressively become common.The network status changes rapidly in response to customer needs and configuration changes,so network configuration changes are also very frequent.However,no matter what changes,the network must ensure the correct conditions,such as isolating tenants from each other or guaranteeing essential services.Once changes occur,it is necessary to verify the after-changed network.Whereas,for the verification of large-scale network configuration changes,many current verifiers show poor efficiency.In order to solve the problem ofmultiple global verifications caused by frequent updates of local configurations in large networks,we present a fast configuration updates verification tool,FastCUV,for distributed control planes.FastCUV aims to enhance the efficiency of distributed control plane verification for medium and large networks while ensuring correctness.This paper presents a method to determine the network range affected by the configuration change.We present a flow model and graph structure to facilitate the design of verification algorithms and speed up verification.Our scheme verifies the network area affected by obtaining the change of the Forwarding Information Base(FIB)before and after.FastCUV supports rich network attributes,meanwhile,has high efficiency and correctness performance.After experimental verification and result analysis,our method outperforms the state-of-the-art method to a certain extent. 展开更多
关键词 Network verification configuration updates network control plane forwarding information base
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Multi-scale Incremental Analysis Update Scheme and Its Application to Typhoon Mangkhut(2018)Prediction
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作者 Yan GAO Jiali FENG +4 位作者 Xin XIA Jian SUN Yulong MA Dongmei CHEN Qilin WAN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第1期95-109,共15页
In the traditional incremental analysis update(IAU)process,all analysis increments are treated as constant forcing in a model’s prognostic equations over a certain time window.This approach effectively reduces high-f... In the traditional incremental analysis update(IAU)process,all analysis increments are treated as constant forcing in a model’s prognostic equations over a certain time window.This approach effectively reduces high-frequency oscillations introduced by data assimilation.However,as different scales of increments have unique evolutionary speeds and life histories in a numerical model,the traditional IAU scheme cannot fully meet the requirements of short-term forecasting for the damping of high-frequency noise and may even cause systematic drifts.Therefore,a multi-scale IAU scheme is proposed in this paper.Analysis increments were divided into different scale parts using a spatial filtering technique.For each scale increment,the optimal relaxation time in the IAU scheme was determined by the skill of the forecasting results.Finally,different scales of analysis increments were added to the model integration during their optimal relaxation time.The multi-scale IAU scheme can effectively reduce the noise and further improve the balance between large-scale and small-scale increments in the model initialization stage.To evaluate its performance,several numerical experiments were conducted to simulate the path and intensity of Typhoon Mangkhut(2018)and showed that:(1)the multi-scale IAU scheme had an obvious effect on noise control at the initial stage of data assimilation;(2)the optimal relaxation time for large-scale and small-scale increments was estimated as 6 h and 3 h,respectively;(3)the forecast performance of the multi-scale IAU scheme in the prediction of Typhoon Mangkhut(2018)was better than that of the traditional IAU scheme.The results demonstrate the superiority of the multi-scale IAU scheme. 展开更多
关键词 multi-scale incremental analysis updates optimal relaxation time 2-D discrete cosine transform GRAPES_MESO Typhoon Mangkhut(2018)
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Finite element model updating for structural damage detection using transmissibility data
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作者 Ahmad Izadi Akbar Esfandiari 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第1期87-101,共15页
This paper presents a new finite element model updating method for estimating structural parameters and detecting structural damage location and severity based on the structural responses(output-only data).The method ... This paper presents a new finite element model updating method for estimating structural parameters and detecting structural damage location and severity based on the structural responses(output-only data).The method uses the sensitivity relation of transmissibility data through a least-squares algorithm and appropriate normalization of the extracted equations.The proposed transmissibility-based sensitivity equation produces a more significant number of equations than the sensitivity equations based on the frequency response function(FRF),which can estimate the structural parameters with higher accuracy.The abilities of the proposed method are assessed by using numerical data of a two-story two-bay frame model and a plate structure model.In evaluating different damage cases,the number,location,and stiffness reduction of the damaged elements and the severity of the simulated damage have been accurately identified.The reliability and stability of the presented method against measurement and modeling errors are examined using error-contaminated data.The parameter estimation results prove the method’s capabilities as an accurate model updating algorithm. 展开更多
关键词 damage detection model updating output-only TRANSMISSIBILITY sensitivity equation
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A Large-Scale Group Decision Making Model Based on Trust Relationship and Social Network Updating
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作者 Rongrong Ren Luyang Su +2 位作者 Xinyu Meng Jianfang Wang Meng Zhao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期429-458,共30页
With the development of big data and social computing,large-scale group decisionmaking(LGDM)is nowmerging with social networks.Using social network analysis(SNA),this study proposes an LGDM consensus model that consid... With the development of big data and social computing,large-scale group decisionmaking(LGDM)is nowmerging with social networks.Using social network analysis(SNA),this study proposes an LGDM consensus model that considers the trust relationship among decisionmakers(DMs).In the process of consensusmeasurement:the social network is constructed according to the social relationship among DMs,and the Louvain method is introduced to classify social networks to form subgroups.In this study,the weights of each decision maker and each subgroup are computed by comprehensive network weights and trust weights.In the process of consensus improvement:A feedback mechanism with four identification and two direction rules is designed to guide the consensus of the improvement process.Based on the trust relationship among DMs,the preferences are modified,and the corresponding social network is updated to accelerate the consensus.Compared with the previous research,the proposedmodel not only allows the subgroups to be reconstructed and updated during the adjustment process,but also improves the accuracy of the adjustment by the feedbackmechanism.Finally,an example analysis is conducted to verify the effectiveness and flexibility of the proposed method.Moreover,compared with previous studies,the superiority of the proposed method in solving the LGDM problem is highlighted. 展开更多
关键词 Large-scale group decision making social network updating trust relationship group consensus feedback mechanism
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An improved interval model updating method via adaptive Kriging models
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作者 Sha WEI Yifeng CHEN +1 位作者 Hu DING Liqun CHEN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第3期497-514,共18页
Interval model updating(IMU)methods have been widely used in uncertain model updating due to their low requirements for sample data.However,the surrogate model in IMU methods mostly adopts the one-time construction me... Interval model updating(IMU)methods have been widely used in uncertain model updating due to their low requirements for sample data.However,the surrogate model in IMU methods mostly adopts the one-time construction method.This makes the accuracy of the surrogate model highly dependent on the experience of users and affects the accuracy of IMU methods.Therefore,an improved IMU method via the adaptive Kriging models is proposed.This method transforms the objective function of the IMU problem into two deterministic global optimization problems about the upper bound and the interval diameter through universal grey numbers.These optimization problems are addressed through the adaptive Kriging models and the particle swarm optimization(PSO)method to quantify the uncertain parameters,and the IMU is accomplished.During the construction of these adaptive Kriging models,the sample space is gridded according to sensitivity information.Local sampling is then performed in key subspaces based on the maximum mean square error(MMSE)criterion.The interval division coefficient and random sampling coefficient are adaptively adjusted without human interference until the model meets accuracy requirements.The effectiveness of the proposed method is demonstrated by a numerical example of a three-degree-of-freedom mass-spring system and an experimental example of a butted cylindrical shell.The results show that the updated results of the interval model are in good agreement with the experimental results. 展开更多
关键词 interval model updating(IMU) non-probabilistic uncertainty adaptive Kriging model surrogate model grey number
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Quantitative Identification of Delamination Damage in Composite Structure Based on Distributed Optical Fiber Sensors and Model Updating
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作者 Hao Xu Jing Wang +3 位作者 Rubin Zhu Alfred Strauss Maosen Cao Zhanjun Wu 《Structural Durability & Health Monitoring》 EI 2024年第6期785-803,共19页
Delamination is a prevalent type of damage in composite laminate structures.Its accumulation degrades structural performance and threatens the safety and integrity of aircraft.This study presents a method for the quan... Delamination is a prevalent type of damage in composite laminate structures.Its accumulation degrades structural performance and threatens the safety and integrity of aircraft.This study presents a method for the quantitative identification of delamination identification in composite materials,leveraging distributed optical fiber sensors and a model updating approach.Initially,a numerical analysis is performed to establish a parameterized finite element model of the composite plate.Then,this model subsequently generates a database of strain responses corresponding to damage of varying sizes and locations.The radial basis function neural network surrogate model is then constructed based on the numerical simulation results and strain responses captured from the distributed fiber optic sensors.Finally,a multi-island genetic algorithm is employed for global optimization to identify the size and location of the damage.The efficacy of the proposed method is validated through numerical examples and experiment studies,examining the correlations between damage location,damage size,and strain responses.The findings confirm that the model updating technique,in conjunction with distributed fiber optic sensors,can precisely identify delamination in composite structures. 展开更多
关键词 Composite structures fiber optic sensor damage identification model updating surrogate model
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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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