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Overload problem research on aperiodic real-time tasks
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作者 吴悦 唐立三 杨洪斌 《Journal of Shanghai University(English Edition)》 CAS 2009年第2期136-141,共6页
In this paper, a novel scheduling mechanism is proposed to handle the real-time overload problem by maximizing the cumulative values of three types of tasks: the soft, the hard and the imprecise tasks. The simulation... In this paper, a novel scheduling mechanism is proposed to handle the real-time overload problem by maximizing the cumulative values of three types of tasks: the soft, the hard and the imprecise tasks. The simulation results show that the performance of our presented mechanism in this paper is greatly improved, much better than that of the other three mechanisms: earliest deadline first (EDF), highest value first (HVF) and highest density first (HDF), under the same conditions of all nominal loads and task type proportions. 展开更多
关键词 aperiodic real-time tasks tasks overload multi-choice knapsack problem nominal load hit value ratio
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Development of All-Weather and Real-Time Bottom-Mounted Monitor of Bed Load Quantity
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作者 窦希萍 左其华 +1 位作者 应强 黄海龙 《China Ocean Engineering》 SCIE EI CSCD 2014年第6期807-814,共8页
Quantity of bed load is an important physical parameter in sediment transport research. Aiming at the difficulties in the bed load measurement, this paper develops a bottom-mounted monitor to measure the bed load tran... Quantity of bed load is an important physical parameter in sediment transport research. Aiming at the difficulties in the bed load measurement, this paper develops a bottom-mounted monitor to measure the bed load transport rate by adopting the sedimentation pit method and resolving such key problems as weighing and desilting, which can achieve long-time, all-weather and real-time telemeasurement of the bed load transport rate of plain rivers, estuaries and coasts. Both laboratory and field tests show that this monitor is reasonable in design, stable in properties and convenient in measurement, and it can be used to monitor the bed load transport rate in practical projects. 展开更多
关键词 quantity of bed load bed load rate sediment transport real-time monitoring measuring apparatus
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Rapid quantification of semen hepatitis B virus DNA by real-time polymerase chain reaction 被引量:25
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作者 Wei-Ping Qian Yue-Qiu Tan +7 位作者 Ying Chen Ying Peng Zhi Li Guang-Xiu Lu Made C. Liu Hsiang-Fu Kung Ming-Ling He Li-Ka Shing 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第34期5385-5389,共5页
AIM: To examine the sensitivity and accuracy of real-time polymerase chain reaction (PCR) for the quantification of hepatitis B virus (HBV) DNA in semen. METHODS: Hepatitis B viral DNA was isolated from HBV carr... AIM: To examine the sensitivity and accuracy of real-time polymerase chain reaction (PCR) for the quantification of hepatitis B virus (HBV) DNA in semen. METHODS: Hepatitis B viral DNA was isolated from HBV carriers' semen and sera using phenol extraction method and QIAamp DNA blood mini kit (Qiagen, Germany). HBV DNA was detected by conventional PCR and quantified by TaqMan technology-based real-time PCR (quantitative polymerase chain reaction (qPCR)). The detection threshold was 200 copies of HBV DNA for conventional PCR and 10 copies of HBV DNA for real time PCR per reaction. RESULTS: Both methods of phenol extraction and QIAamp DNA blood mini kit were suitable for isolating HBV DNA from semen. The value of the detection thresholds was 500 copies of HBV DNA per mL in the semen. The viral loads were 7.5×10^7 and 1.67×10^7 copies of HBV DNA per mL in two HBV infected patients' sera, while 2.14×10^5 and 3.02×10^5 copies of HBV DNA per mL in the semen. CONCLUSION: Real-time PCR is a more sensitive and accurate method to detect and quantify HBV DNA in the semen. 展开更多
关键词 Hepatitis B virus SEMEN real-time polymerase chain reaction Viral load
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Loading System for Full-Scale Heavy-Duty Support Node Test with Multi-Directional Loading Requirements 被引量:3
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作者 王玉银 龚超 +1 位作者 张素梅 郭海山 《Transactions of Tianjin University》 EI CAS 2011年第3期166-174,共9页
This paper presents the design, analysis and experimental study of a loading system for heavy-duty nodes test based on a large-scale multi-directional in-plane loading device, which has been used in a full-scale heavy... This paper presents the design, analysis and experimental study of a loading system for heavy-duty nodes test based on a large-scale multi-directional in-plane loading device, which has been used in a full-scale heavy-duty support node test. Test loads of the support reached 6 567 kN with multi-directional loading requirements, which outrange the capacity of the available loading devices. Through the reinforcement of a large-scale multi-directional inplane loading device, the innovative design of a self-balanced load transferring device, and other arrangement considerations of the loading system, the test was implemented and the loading capacity of the ring was considerably enlarged. Due to the heavy loading requirements, some checking computations of the ring and the load transferring device outranged the limit of the Chinese national code "Code for Design of Steel Structures (GB 50017—2003)", thus elastic-plastic finite element (FE) analysis was carried out on the two devices, and also the real-time monitoring on the whole loading systems during experiments to ensure test safety. FE analysis and test results show that the loading system worked elastically during experiments. 展开更多
关键词 loading system self-balanced design multi-directional loading heavy-duty node
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A Model Predictive Scheduling Algorithm inReal-Time Control Systems 被引量:2
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作者 Mengya Kang Chenglin Wen Chenxi Wu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2018年第2期471-478,共8页
Abstract-The ineffective utilization of power resources has attracted much attention in current years. This paper proposes a real-time distributed load scheduling algorithm considering constraints of power supply. Fir... Abstract-The ineffective utilization of power resources has attracted much attention in current years. This paper proposes a real-time distributed load scheduling algorithm considering constraints of power supply. Firstly, an objective function is designed based on the constraint, and a base load forecasting model is established when aggregating renewable generation and non-deferrable load into a power system, which aims to transform the problem of deferrable loads scheduling into a distributed optimal control problem. Then, to optimize the objective function, a real-time scheduling algorithm is presented to solve the proposed control problem. At every time step, the purpose is to minimize the variance of differences between power supply and aggregate load, which can thus ensure the effective utilization of power resources. Finally, simulation examples are provided to illustrate the effectiveness of the proposed algorithm. 展开更多
关键词 Index Terms-Deferrable loads scheduling electric vehicles(EVs) optimal control power supply real-time distributed con-trol.
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Research on Dynamic Clustering Routing Considering Node Load for Wireless Sensor Networks
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作者 Yi Sun Can Cui +1 位作者 Shanshan Ke Jun Lu 《Communications and Network》 2013年第3期508-511,共4页
Aiming at the problem that node load is rarely considered in existing clustering routing algorithm for Wireless Sensor Networks (WSNs), a dynamic clustering routing algorithm for WSN is presented in this paper called ... Aiming at the problem that node load is rarely considered in existing clustering routing algorithm for Wireless Sensor Networks (WSNs), a dynamic clustering routing algorithm for WSN is presented in this paper called DCRCL (Dynamic Clustering Routing Considering Load). This algorithm is comprised of three phases including cluster head (CH) selection, cluster setup and inter-cluster routing. First, the CHs are selected based on residual energy and node load. Then the non-CH nodes choose a cluster by comparing the cost function of its neighbor CHs. At last, each CH communicates with base station by using multi-hop communication. The simulation results show that comparing with the existing one, the techniques life cycle and date volume of the network are increased by 30.7 percent and 29.8 percent respectively by using the proposed algorithm DCRCL. 展开更多
关键词 Wireless Sensor Network DYNAMIC ROUTING CLUSTERING Algorithm node load
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Evaluating the Effective Microbial Supplementation of Feed on the Load of Salmonella in Two Lymph Nodes of Beef Cattle in Eastern Ethiopia
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作者 Fuad Mohammed Adem Hiko +2 位作者 Yesihak Yusuf Jemal Yusuf Mustefa Musse Ebro 《Agricultural Sciences》 CAS 2022年第11期1223-1233,共11页
The present study was conducted to evaluate the role of effective microbial supplementation to feed on the load of Salmonella in the mesenteric and sub-iliac lymph nodes of beef cattle. Bulls of Harer cattle breed man... The present study was conducted to evaluate the role of effective microbial supplementation to feed on the load of Salmonella in the mesenteric and sub-iliac lymph nodes of beef cattle. Bulls of Harer cattle breed managed at Chercher Oda-Bultum Farmers Union beef Farm were used as study subject. A total of 130 bulls were used using double blinded randomized controlled field trial based on parallel group design from January 2018 to July 2018. The study animals were randomly assigned to the treatment group (n = 100) and control group (n = 30). The feed of treatment group was mixed with EM at dose of 5 × 10<sup>10</sup> cfu/day/head and supplemented for 90, 100 and 115 days while that of the control group was mixed with molasses, which acts as placebo. Both the treatment and control were slaughtered and two lymph nodes were collected from each animal under strict sterile condition and processed for the isolation and identification of Salmonella using standard procedure. A significant (p = 0.001) reduction in the load of Salmonella was observed in the lymph node of treatment group as compared to the control group. The load of Salmonella was significantly affected by length of feeding period and age of bulls. This study indicated that effective microbial supplementation to bulls from Harar cattle reduces the load of Salmonella in the lymph node of beef cattle thereby potentially minimizing the economic and public health impacts of Salmonella infection. 展开更多
关键词 SALMONELLA Lymph node Effective Microbial load
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Correlation between Load of HPV 16 DNA in Cervical Cancer and HPV 16 DNA in Lymph Nodes
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作者 Shuzhen Dai Ding Ma +1 位作者 Weidong Qu Xiaowen Xu 《Clinical oncology and cancer researeh》 CAS CSCD 2009年第6期406-411,共6页
OBJECTIVE To determine the association between viral loadof human papillomavirus 16 (HPV16) DNA in the primary focusof cervical carcinoma and HPV16 DNA in pelvic lymph nodes.METHODS The HPV16 DNA load was measured by ... OBJECTIVE To determine the association between viral loadof human papillomavirus 16 (HPV16) DNA in the primary focusof cervical carcinoma and HPV16 DNA in pelvic lymph nodes.METHODS The HPV16 DNA load was measured by fluorescentquantitation polymerase chain reaction (FQ-PCR) in 17 primaryfoci. HPV16 DNA was detected by polymerase chain reaction(PCR) using HPV16 type-specific primers in 296 pelvic lymphnodes which were from 17 cases of cervical cancer.RESULTS The viral load of HPV16 DNA showed statisticallysignificant differences between tumors with a diameter of < 4cm and ≥ 4 cm (P < 0.05). Seven of 17 cervical cancer cases hadHPV16 DNA positive lymph nodes, designated as the positivegroup, while the remaining 10 without positive lymph nodes wasdesignated the negative group. The average load of HPV16 DNAshowed no significant difference between the 2 groups (P > 0.05).The load of HPV16 in the primary lesion was not associated withthat in the lymph nodes. There were 38 HPV16 DNA positivenodes in the total 296 nodes. The rate of positivity of HPV16 DNAin lymph nodes showed statistically significant differences inconsideration of maximum tumor diameter, tumor differentiation,histologic type, depth of myometial infiltration and the metastaticstatus of the nodes, respectively (P < 0.05).CONCLUSION Viral load of HPV16 in the primary cancer focuscorrelated with the quantity of tumor cells in the primary focusbut not with the existence of HPV DNA positive lymph nodes.Detection of HPV DNA may help to find the early metastases thatcannot be evaluated histopathologically, but the prognostic valueof HPV positive lymph nodes needs further examination. 展开更多
关键词 cervical cancer lymph nodes human papillomavirus viral load.
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Real-Time Operation of Microgrids
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作者 Salem Al-Agtash Asma Alkhraibat +1 位作者 Mohamad Al Hashem Nisrein Al-Mutlaq 《Energy and Power Engineering》 2021年第1期51-66,共16页
Microgrid (MG) systems effectively integrate a generation mix of solar, wind, and other renewable energy resources. The intermittent nature of renewable resources and the unpredictable weather conditions contribute la... Microgrid (MG) systems effectively integrate a generation mix of solar, wind, and other renewable energy resources. The intermittent nature of renewable resources and the unpredictable weather conditions contribute largely to the unreliability of microgrid real-time operation. This paper investigates the behavior of microgrid for different intermittent scenarios of photovoltaic generation in real-time. Reactive power coordination control and load shedding mechanisms are used for reliable operation and are implemented using OPAL-RT simulator integrated with Matlab. In an islanded MG, load shedding can be an effective mechanism to maintain generation-load balance. The microgrid of the German Jordanian University (GJU) is used for illustration. The results show that reactive power coordination control not only stabilizes the MG operation in real-time but also reduces power losses on transmission lines. The results also show that the power losses at some substations are reduced by a range of 6% - 9.8%. 展开更多
关键词 Microgrid real-time Operation Reactive Power Control load Shedding OPAL-RT MATLAB
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Fuzzy Fruit Fly Optimized Node Quality-Based Clustering Algorithm for Network Load Balancing
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作者 P.Rahul N.Kanthimathi +1 位作者 B.Kaarthick M.Leeban Moses 《Computer Systems Science & Engineering》 SCIE EI 2023年第2期1583-1600,共18页
Recently,the fundamental problem with Hybrid Mobile Ad-hoc Net-works(H-MANETs)is tofind a suitable and secure way of balancing the load through Internet gateways.Moreover,the selection of the gateway and overload of th... Recently,the fundamental problem with Hybrid Mobile Ad-hoc Net-works(H-MANETs)is tofind a suitable and secure way of balancing the load through Internet gateways.Moreover,the selection of the gateway and overload of the network results in packet loss and Delay(DL).For optimal performance,it is important to load balance between different gateways.As a result,a stable load balancing procedure is implemented,which selects gateways based on Fuzzy Logic(FL)and increases the efficiency of the network.In this case,since gate-ways are selected based on the number of nodes,the Energy Consumption(EC)was high.This paper presents a novel Node Quality-based Clustering Algo-rithm(NQCA)based on Fuzzy-Genetic for Cluster Head and Gateway Selection(FGCHGS).This algorithm combines NQCA with the Improved Weighted Clus-tering Algorithm(IWCA).The NQCA algorithm divides the network into clusters based upon node priority,transmission range,and neighbourfidelity.In addition,the simulation results tend to evaluate the performance effectiveness of the FFFCHGS algorithm in terms of EC,packet loss rate(PLR),etc. 展开更多
关键词 Ad-hoc load balancing H-MANET fuzzy logic system genetic algorithm node quality-based clustering algorithm improved weighted clustering fruitfly optimization
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基于Super-Node的P2P网络搜索技术研究
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作者 朱钒 林泉泉 易小年 《现代计算机》 2008年第11期42-44,47,共4页
介绍传统超节点结构P2P网络中的查询方法,指出其存在负载均衡问题和单点失效问题。针对其存在的问题引入资源索引和冗余机制,把资源的索引信息分布到多个超节点。通过仿真实验表明,该机制使得各超节点的资源索引信息相对均衡,并且在相... 介绍传统超节点结构P2P网络中的查询方法,指出其存在负载均衡问题和单点失效问题。针对其存在的问题引入资源索引和冗余机制,把资源的索引信息分布到多个超节点。通过仿真实验表明,该机制使得各超节点的资源索引信息相对均衡,并且在相同概率的超节点退出时,提高了查询成功率。 展开更多
关键词 P2P 超节点 资源索引 负载均衡
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Correlation between mitochondrial TRAP-1 expression and lymph node metastasis in colorectal cancer 被引量:13
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作者 Jing-Yan Gao Bao-Rong Song +1 位作者 Jun-Jie Peng Yuan-Ming Lu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第41期5965-5971,共7页
AIM: To evaluate the effect of mitochondrial tumor ne- crosis factor receptor-associated protein-1 (TRAP-l) on the lymph node metastasis (LNM) in Chinese colorectal cancer (CRC) patients, and develop potential ... AIM: To evaluate the effect of mitochondrial tumor ne- crosis factor receptor-associated protein-1 (TRAP-l) on the lymph node metastasis (LNM) in Chinese colorectal cancer (CRC) patients, and develop potential LNM- associated biomarkers for CRC using quantitative real- time polymerase chain reaction (RT-PCR) analysis. METHODS: Differences in mitochondrial TRAP-1 gene expression between primary CRC with LNM (LNM CRC) and without LNM (non-LNM CRC) were assessed in 96 Chinese colorectal carcinoma samples using quantita- tive RT-PCR analysis, Western blotting, and confirmed with immunohistochemical assay. The relationship between clinicopathological parameters and potential diaclnostic biomarkers was also examined.RESULTS: TRAP-1 was significantly upregulated in LNM CRC compared with non-LNM CRC, which was confirmed by RT-PCR, Western blotting and immuno- histochemical assay. The expression of TRAP-1 in two different metastatic potential human colorectal cancer cell lines, LoVo and HT29, was analyzed with Western blotting. The expression level of TRAP-1 was dramati- cally higher in LoVo than in HT29. Overexpression of TRAP-1 was significantly associated with LNM (90.2% in LNM group vs 22% in non-LNM group, P 〈 0.001), the advanced tumor node metastasis stage (89.1% in LNM group vs 26.9% in non-LNM group, P 〈 0.001), the increased 5-year recurrence rate (82.7% in LNM group vs 22.6% in non-LNM group, P 〈 0.001) and the decreased 5-year overall survival rate (48.4% in LNM vs 83.2% in non-LNM group, P 〈 0.001). Univariate and multivariate analyses indicated that TRAP-1 expression was an independent prognostic factor for recurrence and survival of CRC patients (Hazard ratio of 2.445 in recurrence, P = 0.017; 2.867 in survival, P = 0.028). CONCLUSION: Mitochondria TRAP-1 affects the lymph node metastasis in CRC, and may be a potential bio- marker for LNM and a prognostic factor in CRC. Over- expression of TRAP-1 is a predictive factor for the poor outcome of colorectal cancer patients. 2012 Baishideng. All rights reserved 展开更多
关键词 Colorectal cancer Lymph node metastasis PROGNOSIS Quantitative real-time polymerase chain reaction analysis Hsp90 family Mitochondria tumor necrosis factor receptor-associated protein-1
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Screening of lymph nodes metastasis associated lncRNAs in colorectal cancer patients 被引量:2
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作者 Jun Han Long-Fei Rong +5 位作者 Chuan-Bin Shi Xiao-Gang Dong Jie Wang Bao-Lin Wang Hao Wen Zhen-Yu He 《World Journal of Gastroenterology》 SCIE CAS 2014年第25期8139-8150,共12页
AIM: To screen lymph nodes metastasis associated long noncoding RNAs (lncRNAs) in colorectal cancer through microarray analysis.
关键词 Long noncoding RNAs Colorectal cancer Lymph nodes metastasis Quantitative real-time polymerase chain reaction MICRORNA
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Optimization of Load Balancing Algorithm for Virtual Machine Dynamic Migration under Mobile Cloud Computing
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作者 Weijin Jiang Fang Ye +3 位作者 Shengjie Yang Wei Liu Xiaoliang Liu Sijian Lv 《China Communications》 SCIE CSCD 2020年第6期237-245,共9页
As one of the key technologies of cloud computing,the virtualization technology can virtualize all kinds of resources and integrate them into the unified planning of the cloud computing management platform.The migrati... As one of the key technologies of cloud computing,the virtualization technology can virtualize all kinds of resources and integrate them into the unified planning of the cloud computing management platform.The migration of virtual machines is one of the important technologies of virtual machine applications.However,there are still many deficiencies in the implementation of load balancing by virtual machine dynamic migration in cloud computing.Traditional triggering strategy thresholds are mostly fixed.If there is an instantaneous peak,it will cause migration,which will cause a waste of resources.In order to solve this problem,based on improving the dynamic migration framework,this paper proposes node selection optimization algorithm and node load balancing strategy and designs a prediction module,which uses a one-time smooth prediction to avoid the shortcoming of peak load moment.The simulation experiments and conclusions analysis results show that the fusion algorithm has performance advantages obvious. 展开更多
关键词 cloud computing dynamic migration load balance node selection load value prediction
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Leishmania tropica: The comparison of two frequently-used methods of parasite load assay in vaccinated mice
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作者 Fatemeh Nemati Zargaran Mosayeb Rostamian +1 位作者 Alisha Akya Hamid MNiknam 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2020年第6期248-253,共6页
Objective:To compare limiting dilution assay and real-time PCR methods in Leishmania tropica parasite load measurement in vaccinated mice.Methods:BALB/c mice were vaccinated by Leishmania tropica soluble Leishmania an... Objective:To compare limiting dilution assay and real-time PCR methods in Leishmania tropica parasite load measurement in vaccinated mice.Methods:BALB/c mice were vaccinated by Leishmania tropica soluble Leishmania antigen or recombinant Leishmania tropica stressinducible protein-1 with/without adjuvant.After three vaccinations,mice were challenged by Leishmania tropica promastigotes.Two months after challenge,the draining lymph nodes of mice footpad were removed and parasite load was assayed by limiting dilution assay and real-time PCR methods.Limiting dilution assay was done by diluting tissue samples to extinction in a biphasic medium.For real-time PCR,DNA of the lymph nodes was extracted,equal dilutions of each sample were prepared and hot-start real-time PCR was done using appropriate primers.The data of the two methods were compared by appropriate statistical methods.Results:Both methods were able to measure different levels of parasite load in vaccinated/unvaccinated mice.In addition,wherever parasite load of a group was estimated high(or low)by one method,the estimated parasite load by another method was the same,although statistically significant differences were found between some groups.Conclusions:Both methods lead to approximately similar results in terms of differentiating parasite load of the experimental groups.However,due to the lower errors and faster process,the real-time PCR method is preferred. 展开更多
关键词 LEISHMANIA tropica Vaccinated MICE LIMITING DILUTION ASSAY PARASITE load assay real-time PCR
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一个Fabric Node客户端负载测试工具及实例分析
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作者 高锦博 严悍 +1 位作者 李雪飞 周亚茹 《计算机与数字工程》 2020年第6期1496-1500,共5页
Hyperledger Fabric区块链的性能是一个重要问题。在现有的文献中缺乏针对Fabric 1.3版本的研究,并且缺乏基于Fabric SDK Node的客户端负载测试工具。对此设计一个负载测试工具作为Fabric网络Node客户端测试工具。该工具支持Fabric最新... Hyperledger Fabric区块链的性能是一个重要问题。在现有的文献中缺乏针对Fabric 1.3版本的研究,并且缺乏基于Fabric SDK Node的客户端负载测试工具。对此设计一个负载测试工具作为Fabric网络Node客户端测试工具。该工具支持Fabric最新版本1.3,通过改变并发数,并以最大交易请求速率施加负载,采集并分析数据。作为实例,分析区块大小对交易的读写性能的影响。 展开更多
关键词 FABRIC nodeJs 负载 区块大小 交易
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Research on virtual node placement optimization strategy of cloud platform for information acquisition
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作者 帅愉燕 Wei Gaofeng +1 位作者 Zhang Zhaoxin Zhang Lizhe 《High Technology Letters》 EI CAS 2018年第3期279-286,共8页
A virtual node placement strategy based on service-aware is proposed for an information acquisition platform. The performance preferences and types of services in the information acquisition platform are analyzed as w... A virtual node placement strategy based on service-aware is proposed for an information acquisition platform. The performance preferences and types of services in the information acquisition platform are analyzed as well as a comparison of the running time of services both in virtual node centralized and decentralized placing. All physical hosts are divided into different sub-clusters by using the analytic hierarchy process( AHP),in order to fit service of different performance preferences. In the sub-cluster,both load balance and quality of service are taken into account. Comparing with the heuristic algorithm,the experiment results show that the proposed placement strategy is running for a shorter time. And comparing with the virtual node placement strategy provided by OpenStack,the experiment results show that the proposed placement strategy can improve the execution speed of service in the information acquisition platform,and also can balance the load which improves resources utilization. 展开更多
关键词 virtual node placement service-aware performance preference analytic hierarchy process (AHP) load balance
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Analysis of composite material interface crack face contact and friction effects using a new node-pairs contact algorithm
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作者 钟志鹏 何郁波 万水 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第6期333-340,共8页
A new node-pairs contact algorithm is proposed to deal with a composite material or bi-material interface crack face contact and friction problem (e.g., resistant coating and thermal barrier coatings) subjected to c... A new node-pairs contact algorithm is proposed to deal with a composite material or bi-material interface crack face contact and friction problem (e.g., resistant coating and thermal barrier coatings) subjected to complicated load conditions. To decrease the calculation scale and calculation errors, the local Lagrange multipliers are solved only on a pair of contact nodes using the Jacobi iteration method, and the constraint modification of the tangential multipliers are required. After the calculation of the present node-pairs Lagrange multiplier, it is turned to next contact node-pairs until all node-pairs have finished. Compared with an ordinary contact algorithm, the new local node-pairs contact algorithm is allowed a more precise element on the contact face without the stiffness matrix singularity. The stress intensity factors (SIFs) and the contact region of an infinite plate central crack are calculated and show good agreement with those in the literature. The contact zone near the crack tip as well as its influence on singularity of stress fields are studied. Furthermore, the frictional contacts are also considered and found to have a significant influence on the SIFs. The normalized mode-II stress intensity factors KII for the friction coefficient decrease by 16% when f changes from 1 to 0. 展开更多
关键词 contact and friction node-pairs contact algorithm interface crack mixed mode loading stress intensity factors
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一种新型结构与保温一体化复合墙板节点试验
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作者 马少春 谷宇 鲍鹏 《防灾减灾工程学报》 CSCD 北大核心 2024年第2期396-403,共8页
为解决复合墙板节点常见的保温板易燃、易脱落等棘手问题,并使其抗震性能良好。给出了一种新型的结构与保温一体化陶粒混凝土T型复合墙板节点。该复合墙板节点具有夹芯独特构造优势,主要表现在绿色节能,轻质高强,力学性能好,保温系统连... 为解决复合墙板节点常见的保温板易燃、易脱落等棘手问题,并使其抗震性能良好。给出了一种新型的结构与保温一体化陶粒混凝土T型复合墙板节点。该复合墙板节点具有夹芯独特构造优势,主要表现在绿色节能,轻质高强,力学性能好,保温系统连接可靠,还能杜绝火灾的发生。通过对T型复合墙板节点进行抗震试验,分别研究了其滞回性能、破坏机理、承载及变形能力、延性、耗能、损伤等。结果表明:一体化复合墙板节点的破坏顺序为腹板-翼缘-节点核心区;薄弱位置主要发生在腹板脚部,混凝土被拉裂或压碎,钢筋被拉长或压弯等;节点核心区受力相对良好,安全储备充足;符合“强节点,弱构件”设计要求和墙板革新发展政策。延性系数大于3,墙板节点安全性能良好。通过损伤指标评估分析,了解了试件各阶段工作状态。 展开更多
关键词 结构与保温一体化 复合墙板节点 抗震试验 滞回及骨架曲线 损伤指标
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考虑负载和时延的船舶无线网络节点流量控制
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作者 黄清 《舰船科学技术》 北大核心 2024年第7期128-131,共4页
针对船舶无线网络稳定性较差,易出现负载失衡、信息传输时延高的问题,研究考虑负载和时延的船舶无线网络节点流量控制方法。此方法利用有向图优化船舶无线网络结构与节点分层结构;计算船舶无线网络节点负载占用率与可用率,提取负载均衡... 针对船舶无线网络稳定性较差,易出现负载失衡、信息传输时延高的问题,研究考虑负载和时延的船舶无线网络节点流量控制方法。此方法利用有向图优化船舶无线网络结构与节点分层结构;计算船舶无线网络节点负载占用率与可用率,提取负载均衡的节点通信路径;使用基于RTT的拥塞流量分配算法,以缩短延时为目标,考虑负载和时延的船舶无线网络节点流量控制。实验结果显示:此方法使用后,船舶紧急业务、关键业务、普通业务在无线网络中分组投递率提升,解决了负载失衡问题;紧急业务端到端时延低于100 ms,关键业务与普通业务端到端时延低于1 000 ms,流量控制效果较好。 展开更多
关键词 负载和时延 船舶无线网络 节点流量 分配控制
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