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Novel ensemble learning based on multiple section distribution in distributed environment
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作者 Fang Min 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第2期377-380,共4页
Because most ensemble learning algorithms use the centralized model, and the training instances must be centralized on a single station, it is difficult to centralize the training data on a station. A distributed ense... Because most ensemble learning algorithms use the centralized model, and the training instances must be centralized on a single station, it is difficult to centralize the training data on a station. A distributed ensemble learning algorithm is proposed which has two kinds of weight genes of instances that denote the global distribution and the local distribution. Instead of the repeated sampling method in the standard ensemble learning, non-balance sampling from each station is used to train the base classifier set of each station. The concept of the effective nearby region for local integration classifier is proposed, and is used for the dynamic integration method of multiple classifiers in distributed environment. The experiments show that the ensemble learning algorithm in distributed environment proposed could reduce the time of training the base classifiers effectively, and ensure the classify performance is as same as the centralized learning method. 展开更多
关键词 distributed environment ensemble learning multiple classifiers combination.
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Towards delivery of situational information in distributed environments
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作者 孙成强 Yongseong Cho +1 位作者 Jongsun Choi Jaeyoung Choi 《Journal of Measurement Science and Instrumentation》 CAS 2013年第3期282-285,共4页
information obtained from physical environments and provides context-aware services automatically based on the information retrieved.And the workflow in the business processes and the distributed computing environment... information obtained from physical environments and provides context-aware services automatically based on the information retrieved.And the workflow in the business processes and the distributed computing environments have supported the automation of services by connecting tasks.The workflow needs to specify ubiquitous situational information as state-transition constraints.However,the delivery and use of sensor data in the workflow is a difficult problem for the robot system.In order to bridge the gap between applications and low-level constructs and to acquire raw situational information for the execution of the context-aware workflow in the robot systems,this paper presents an approach which can achieve the sensor data transmission between a sensing server and a robot system easily. 展开更多
关键词 PUBLISH/SUBSCRIBE robot service WORKFLOW situational information distributed environments
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A Mobile Agent-Based Prototype of HeterogeneousDistributed Virtual Environment Systems 被引量:1
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作者 Ji Qingge(Dept. of Computer Science & Engineering, Harbin Institute of Technology, 150001, P. R. China)Wang Dongmu(Beijing Simulation Center, 100854, P. R. China)Hong Bingrong(Dept. of Computer Science & Engineering, Harbin Institute of Technology, 150001 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2000年第2期61-65,共5页
Mobile agents provide a new method for the distributed computation. This paper presents the advantages of using mobile agents in a distributed virtual environment (DVE) system, and describes the architecture of hetero... Mobile agents provide a new method for the distributed computation. This paper presents the advantages of using mobile agents in a distributed virtual environment (DVE) system, and describes the architecture of heterogeneous computer's distributed virtual environment system (HCWES) designed to populate some mobile agents as well as stationary agents. Finally, the paper introduces how heterogeneous computer network communication is to be realized. 展开更多
关键词 distributed virtual environment Mobile agent distributed computing
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Research on Application Technology Oriented Rapid Response Manufacturing in the Distributed Network Environment
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作者 JIN Ji-wen, NI Yan-rong, XI Jun-tong, FAN Fei-ya, JIN Ye (CIM Institute, Department of Mechanical Engineering, Shanghai Jiaotong University, Shanghai 200030, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期43-44,共2页
A new chance of developing traditional manufacturing industry comes forth with the development of network technology. Application technology oriented rapid response manufacturing in the distributed network environment... A new chance of developing traditional manufacturing industry comes forth with the development of network technology. Application technology oriented rapid response manufacturing in the distributed network environments, that is, how to take advantage of the Intranet and Internet, combine the numerous manufacturing resources spread around the region, the country and even the globe is the key to the agile design, manufacturing and the buildup of comprehensively competitive power, at the same time, is also an important research direction in the field of advanced manufacturing technology. Rapid response manufacturing in the distributed network environment is a newly manufactory pattern that can be used to implement the conception of agile design and manufacturing, but there are some new problems coming with it, which will directly influence the enterprise’s ability of rapid response in the distributed network manufacturing pattern and lead to the failure of the league and the lost of the given orders. In this paper, we establish some approaches to solve these problems in product development process. The paper then presents the research on key application technologies and solutions includes: network safety strategy which guarantees data transferring among the leaguer members, production data management based on Web/DOT (Distributed Object Technology) and XML criteria which guarantees data exchange in structure-variance characteristic environments, the network platform which provides the conversion service of different types of CAD files each other. All of these solutions are aim for technology problems existing in the distributed network environments and among the league members. Finally, the paper takes one project, that is, the establishment of the online application service system for Shanghai Advance Manufacturing Technology Research Center as a good instance. 展开更多
关键词 distributed network environment rapid response manufacturing data exchange
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The Network Architecture and Protocols for Distributed Virtual Environment
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作者 杨永高 潘启敬 《Journal of Modern Transportation》 1998年第2期9-22,共14页
In this paper, the properties of distributed virtual environment (DVE) and the requirements on computer networks is briefly reviewed. A multicast protocol, called sender initiated grouping multicast protocol for DVE... In this paper, the properties of distributed virtual environment (DVE) and the requirements on computer networks is briefly reviewed. A multicast protocol, called sender initiated grouping multicast protocol for DVE (SIGMP), is proposed. This new multicast protocol is based on a novel concept, multicast group (MG), which divides all participants in a DVE system into groups, among which there is a multicast group trustee (MGT) node to manage the group. The protocol provides unreliable/reliable, totally ordered and multiple to multiple multicast transmission service for DVE systems without sacrificing the communication efficiency heavily. At the same time, reliable unicast and one to multiple multicast transmission services are also supported. The performance analysis of the new protocols is also presented. Based on SIGMP, a simple demonstration of DVE system is designed and implemented. This demo system is running on several SGI workstations connected by a FDDI and Ethernet network. 展开更多
关键词 distributed virtual environments computer networks protocols MULTICAST
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CCA Inferred Environmental Implications of Common Ostracods on the Qinghai-Tibetan Plateau 被引量:4
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作者 SONG Gao WANG Hailei ZHENG Mianping 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第2期585-597,共13页
103 surface sediment samples in 71 water bodies, such as lakes with different salinity, swamps, shallow puddles and rivers on the Qinghai-Tibetan Plateau (QTP), were collected to study the ecological distribution of... 103 surface sediment samples in 71 water bodies, such as lakes with different salinity, swamps, shallow puddles and rivers on the Qinghai-Tibetan Plateau (QTP), were collected to study the ecological distribution of living ostracods and their environmental implications. Total of 12 genus and 45 species living ostracods are identified. According to the frequencies and abundance of ostracods occurrence, Limnocythere dubiosa, Limnocytherellina kunlunensis, llyocypris bradyi, Candona candida, Eucypris rischtanica and Leucocythere dilatata are the common species on the QTP, with occurrence frequency of more than 8 and abundance of more than 570 in the 71 water bodies. Among them, L. dubiosa, occurring in 28 water bodies with 2177 shells, is the most widely distributed ostracod in this research. Canonical Correspondence Analysis (CCA) indicates high correlation between species and environmental variables, suggesting that the occurrence of species is strongly related to the changes in ecological conditions of habitats. Among eight environmental factors, salinity and pH value are the most affective variables that influence the species occurrence. L. kunlunensis is positively correlated with salinity while E. rischtanica is negatively correlated with salinity. C. candida has a positive correlation with salinity, as does I. bradyi although there is not such a strong correlation. L. dubiosa displays a positive correlation with pH value. Consequently, we discuss the environmental implications of the common living ostracods on the QTP based on the CCA as well as the distribution of ostracod species in different salinity and pH values water. L. dubiosa, L. kunlunensis and E. rischtanica are euryhaline species, among which, L. dubiosa is the most adaptable species on the QTP with large occurrence in sundry salinity water and the most widely adaptive range for pH values. L. kunlunensis prefers to saline water while E. rischtanica prefers to fresh water. Both L. kunlunensis and E. rischtanica can live in water from faintly acid to alkaline, in contrast, L. dubiosa only appears in neutral and alkaline water bodies. L bradyi only occurs in fresh water and oligohaline water with a large pH tolerance range tolerance range from weakly acidic water to alkaline water weakly acidic water to alkaline water. C. Candida lives in freshwater, with pH value above eight. The six common species reach maximum abundance in alkaline water (pH 8-10) except for llyocypris bradyi. 展开更多
关键词 Qinghai-Tibetan Plateau common living ostracods environmental implications ecological distribution Canonical Correspondence Analysis (CCA)
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Environmental Correlates of Distribution of the 25 Broad-leaved Tree Species Indigenous to Guangdong Province,China 被引量:15
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作者 SuZhiyao ChenBeiguang ChangYong YangJiazhi 《Forestry Studies in China》 CAS 2004年第4期23-28,共6页
关键词 indigenous tree species environmental correlate distribution horizontal pattern NMS CCA Guangdong Prov- ince
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Spatiotemporal heterogeneity of phytoplankton diversity and its relation to water environmental factors in the southern waters of Miaodao Archipelago,China 被引量:3
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作者 ZHENG Wei LI Fen +8 位作者 SHI Honghua HUO Yuanzi LI Yan CHI Yuan GUO Zhen WANG Yuanyuan SHEN Chengcheng LIU Jian QIAO Mingyang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第2期46-55,共10页
To study the water quality influenced by the anthropogenic activities and its impact on the phytoplankton diversity in the surface waters of Miaodao Archipelago, the spatiotemporal variations in phytoplankton communit... To study the water quality influenced by the anthropogenic activities and its impact on the phytoplankton diversity in the surface waters of Miaodao Archipelago, the spatiotemporal variations in phytoplankton communities and the environmental properties of the surface waters surrounding the Five Southern Islands of Miaodao Archipelago were investigated, based on seasonal field survey conducted from November 2012 to August 2013. During the survey, a total of 109 phytoplankton species from 3 groups were identified in the southern waters of Miaodao Archipelago, of which 77 were diatoms, 29 were dinoflagellates, and 3 were chrysophytes. Species number was higher in winter(73), moderate in autumn(70), but lower in summer(31) and spring(27). The species richness index in autumn(5.92) and winter(4.28) was higher than that in summer(2.83) and spring(1.41).The Shannon-Wiener diversity index was high in autumn(2.82), followed by winter(1.99) and summer(1.92), and low in spring(0.07). The species evenness index in autumn(0.46) and summer(0.39) was higher than that in winter(0.32) and spring(0.02). On the basis of principal component analysis(PCA) and redundancy analysis(RDA), we found that dissolved inorganic nitrogen(DIN) and chemical oxygen demand(COD) in spring, COD in summer, p H in autumn, and salinity and oil pollutant in winter, respectively, showed the strongest association with the distribution of phytoplankton diversity. The spatial heterogeneity of the southern waters of Miaodao Archipelago was quite obvious, and three zones, i.e., northeastern, southwestern and inter-island water area, were identified by cluster analysis(CA) based on key environmental variables. 展开更多
关键词 Miaodao Archipelago environmental factors spatial distribution phytoplankton statistical analysis
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Types, Metallogenic Environments and Characteristics of Temporal and Spatial Distribution of Copper Deposits in China 被引量:5
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作者 Wang Zhitian and Qin Kezhang Beijing Institute of Geology for Mineral Resources, CNNC, Beijing Zhang Zhongmin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1989年第1期79-92,共14页
Based upon a comprehensive study of 123 copper deposits in China. this paper reaches the following conclusions: 1. The crust in China was solidified pretty late; with the accretion of the plate, the copper mineralizat... Based upon a comprehensive study of 123 copper deposits in China. this paper reaches the following conclusions: 1. The crust in China was solidified pretty late; with the accretion of the plate, the copper mineralization moved towards its margin in space and became successively younger in age. 2. The major copper ore types ever found in the world have mostly been discovered in China, in which the porphyry type seems to be the most important and the massive sulfide type in the transitional bed between marine clastic and carbonate rocks is clearly defined. 3. Carbonate strata are widespread in China and their deposition lasted for a long geological period, so the proportion of copper deposits occurring in them is large as compared with other parts of the world. 4. Seven metallogenic epochs can be recognized, in which the Mesozoic one plays the leading role and the middle(late) Palaeozoic and Cenozoic ones are next in importance. Mineralization was comparatively simple in the early geological period. and became diversified later on. In the early epochs copper deposits related to basaltic magmatism and metamorphosed marine sediments predominated, whereas in the later epochs those related to granitic magmatism and continental sedimentation were dominant. 5. There exist in China thirteen metallogenic provinces, of which the Lower Yangtze downwarping belt, Sanjiang fold system, Jiangnan axis and Xikang-Yunnan axis are of greater significance. 6. The crustal mobility in China was rather pronounced, the polycyclic evolution of the crust has resulted in such obvious phenomena as the inheritance of mineralization, the coexistence of various types and the superposition of different genetic types. 展开更多
关键词 Metallogenic environments and Characteristics of Temporal and Spatial Distribution of Copper Deposits in China TYPES
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A Distributed LRTCO Algorithm in Large-Scale DVE Multimedia Systems
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作者 Hangjun Zhou Guang Sun +3 位作者 Sha Fu Wangdong Jiang Tingting Xie Danqing Duan 《Computers, Materials & Continua》 SCIE EI 2018年第7期73-89,共17页
In the large-scale Distributed Virtual Environment(DVE)multimedia systems,one of key challenges is to distributedly preserve causal order delivery of messages in real time.Most of the existing causal order control app... In the large-scale Distributed Virtual Environment(DVE)multimedia systems,one of key challenges is to distributedly preserve causal order delivery of messages in real time.Most of the existing causal order control approaches with real-time constraints use vector time as causal control information which is closely coupled with system scales.As the scale expands,each message is attached a large amount of control information that introduces too much network transmission overhead to maintain the real-time causal order delivery.In this article,a novel Lightweight Real-Time Causal Order(LRTCO)algorithm is proposed for large-scale DVE multimedia systems.LRTCO predicts and compares the network transmission times of messages so as to select the proper causal control information of which the amount is dynamically adapted to the network latency variations and unconcerned with system scales.The control information in LRTCO is effective to preserve causal order delivery of messages and lightweight to maintain the real-time property of DVE systems.Experimental results demonstrate that LRTCO costs low transmission overhead and communication bandwidth,reduces causal order violations efficiently,and improves the scalability of DVE systems. 展开更多
关键词 distributed computing distributed virtual environment multimedia system causality violation causal order delivery real time
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Distributed Trusted Computing for Blockchain-Based Crowdsourcing
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作者 Yihuai Liang Yan Li Byeong-Seok Shin 《Computers, Materials & Continua》 SCIE EI 2021年第9期2825-2842,共18页
A centralized trusted execution environment(TEE)has been extensively studied to provide secure and trusted computing.However,a TEE might become a throughput bottleneck if it is used to evaluate data quality when colle... A centralized trusted execution environment(TEE)has been extensively studied to provide secure and trusted computing.However,a TEE might become a throughput bottleneck if it is used to evaluate data quality when collecting large-scale data in a crowdsourcing system.It may also have security problems compromised by attackers.Here,we propose a scheme,named dTEE,for building a platform for providing distributed trusted computing by leveraging TEEs.The platform is used as an infrastructure of trusted computations for blockchain-based crowdsourcing systems,especially to securely evaluate data quality and manage remuneration:these operations are handled by a TEE group.First,dTEE uses a public blockchain with smart contracts to manage TEEs without reliance on any trusted third parties.Second,to update TEE registration information and rule out zombie TEEs,dTEE uses a reporting mechanism.To attract TEE owners to join in and provide service of trusted computations,it uses a fair monetary incentive mechanism.Third,to account for malicious attackers,we design a model with Byzantine fault tolerance,not limited to a crash-failure model.Finally,we conduct an extensive evaluation of our design on a local cluster.The results show that dTEE finishes evaluating 10,000 images within one minute and achieves about 65 tps throughput when evaluating Sudoku solution data with collective signatures both in a group of 120 TEEs. 展开更多
关键词 Crowdsourcing blockchain distributed trusted execution environment Byzantine fault tolerance
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Integration of Manufacturing Services into Virtual Environments over the Internet
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作者 Huiping Shang Zhengxu Zhao 《International Journal of Automation and computing》 EI 2004年第1期89-106,共18页
Virtual reality (VR) is a rapidly developing technology that has a wide spectrum of industrial and commercial applications. Networked (distributed or shared) virtual environments (VE) are of growing interest to modern... Virtual reality (VR) is a rapidly developing technology that has a wide spectrum of industrial and commercial applications. Networked (distributed or shared) virtual environments (VE) are of growing interest to modern manufacturing industry; a dominating use of networked virtual manufacturing environments (VMEs) is on-line visualisation and collaborative control of 3D information. This has to be supported by real-time data transfer. To meet a broad range of common requirements for Internet-based VE communications, particularly for virtual manufacturing and collaborative design and control, this paper presents a networked virtual environment system that is designed to support networked virtual design and manufacturing. The system is implemented with manufacturing message specification (MMS) standards so as to integrate a range of manufacturing services into networked VEs over the Internet. 展开更多
关键词 distributed virtual environment networked virtual environment shared virtual environment virtual reality (VR) virtual environment (VE) virtual manufacturing virtual manufacturing device (VMD) manufacturing message specification (MMS) communication protocol
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Analysis of the negative effects of groundwater exploitation on geological environment in Asia
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作者 ZHANG Jian-kang WEN Xue-ru +2 位作者 GAO Yun YUE Chen YI Qing 《Journal of Groundwater Science and Engineering》 2015年第2期202-212,共11页
This paper summarizes the negative effects on geological environment caused by groundwater exploitation and its distribution. There are seven main types of the geological environment negative effects, which are genera... This paper summarizes the negative effects on geological environment caused by groundwater exploitation and its distribution. There are seven main types of the geological environment negative effects, which are generally as follows:(1) Constant decrease of groundwater level is mainly distributed in China(East Asia), India(South Asia), Tajikistan(Central Asia) and Saudi Arabia(West Asia);(2) land subsidence occurs mainly in eastern plains of East Asia and west Siberian Plain of North Asia;(3) seawater intrusion occurs mainly in China, Japan and South Korea in East Asia, Philippines and Indonesia in Southeast Asia, the Indian coastal areas in South Asia;(4) groundwater level decline caused by groundwater exploitation in oil fields;(5) mining collapse is mainly in 50° to 70° north latitude band;(6) the total area of karst collapse in China of East Asia is as much as 197.05 km^2; and(7) ground fracture is mainly distributed in the North China Plain, Fenwei Plain and the Yangtze River Delta. Asia can be divided into 6 zones in terms of the geological environment negative effect caused by groundwater exploitation. According to analysis, with the increasing intensity of human activities, geological environment issues become more and more serious, therefore it is vital to control the human activities within the scope of 5× 10~5 people/km^2 to 9.9× 10~5 people/km^2 for the effective control of the size of the affected area by geological environment problems. 展开更多
关键词 ASIA Groundwater development Geological environment negative effect and distributed regions Severity of geological environment problems
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Research on Networked Rapid Product Development Process
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作者 NI Yan-rong, FAN Fei-ya, JIN Ji-wen, YAN Jun-qi (CIM Institute, Department of Mechanical Engineering, Shanghai Jiaotong University, Shanghai 200030, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期158-159,共2页
Today the cycle time of the product develop is requ ir ed to be shortened. At the same time the requirement of the customers becomes mo re and more diverse and complex. The capability of the develop unit is limited b ... Today the cycle time of the product develop is requ ir ed to be shortened. At the same time the requirement of the customers becomes mo re and more diverse and complex. The capability of the develop unit is limited b ecause of the existence of heterogeneous systems and distributed environments. I n this paper, we bring forward a new approach to solve the problem in product de velopment process. We also settle part key technologies in it. A great deal of information from all kinds of sources in the distributed develop ment process is interweaved. The solution to organize the workflow and manage th e information in the process is called for anxiously. We use a new approach that is asynchronous and synchronous coupling product development approach based on the network. The approach extends the develop process from the time axis. Then t he activities in the process are organized from the asynchronous and synchronous aspects. The state of every activity projects at the ASN (active semantic netwo rk). The ASN includes decision system, intelligent agent, user interface and net work. The ASN decides the types and states of the activities and deals with the couple relationship among them. The knowledge stored in ASN is open to all users through the relative interfaces. Every specialist keeps contact with their user s relying on collaborative platform implements CSCW (computer support collaborat ive work) that integrated product/process design and development. The lack of gl obal communication in product development process can be prevented in the most d egree. The key technologies that exist in the asynchronous and synchronous coupling pro duct develop approach include: integrated development structure, orderly organiz ation of information, transparent management of process, agile transfer of infor mation and rapid prototype. The development process can be completed quickly by these technologies. The technologies involve wide content. In this paper, we dis cuss some key technologies. We validate the approach by the projectrapid response manufacturing a pplication in the distributed environment. The expensive device, high technology and low using lead to RE (Rapid engineering) and RP (Rapid prototype) service a pplication by the network. RE and RP develop rapidly due to the accelerated prod uct development process. RE and RP application service platform is built in the project. 展开更多
关键词 distributed environment asynchronous and synchro nous coupled active semantic network product development process
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Maintaining Consistency Based on Timely Updating Records List in Workflow Data
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作者 WU Hongli YIN Baolin ZHAO Xiao XIANG Gang 《Wuhan University Journal of Natural Sciences》 CAS 2008年第4期481-484,共4页
In order to settle the problem of workflow data consis-tency under the distributed environment, an invalidation strategy based-on timely updating record list is put forward. The strategy adopting the method of updatin... In order to settle the problem of workflow data consis-tency under the distributed environment, an invalidation strategy based-on timely updating record list is put forward. The strategy adopting the method of updating the records list and the recovery mechanism of updating message proves the classical invalidation strategy. When the request cycle of duplication is too long, the strategy uses the method of updating the records list to pause for sending updating message; when the long cycle duplication is requested again, it uses the recovery mechanism to resume the updating message. This strategy not only ensures the consistency of the workflow data, but also reduces the unnecessary network traffic. From theoretical comparison with those common strategies, the unnecessary network traffic of this strategy is fewer and more stable. The simulation results validate this conclusion. 展开更多
关键词 distributed environment workflow data records list update cycle threshold consistency maintenance
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Research Progress of Trust Evaluation Model
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作者 ZHOU Guoqiang PAN Fangrui +1 位作者 ZHANG Weifeng GUO Jian 《Wuhan University Journal of Natural Sciences》 CAS 2008年第4期391-395,共5页
Software systems in distributed environment are changing from a close and relatively static form, whose users are familiar with each other, to an open and highly dynamic mode, which can be visited by public. In such c... Software systems in distributed environment are changing from a close and relatively static form, whose users are familiar with each other, to an open and highly dynamic mode, which can be visited by public. In such circumstance, trust evaluation model becomes focus of intense research at current time. Trust evaluation model establishes a management framework of trust relationship between entities, involving expression and measurement of trust, comprehensive calculation of direct trust value and recommended trust value, and recognition of malicious entities and recommendations. Based on the analysis of several typical trust evaluation models, the classification of trust evaluation ideas and modes is discussed, the questions existing in current research and the directions of future research are pointed out. 展开更多
关键词 distributed environment TRUST trust evaluation model trust path
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Study on spatial and temporal distribution of planktonic amphipoda in the East China Sea 被引量:4
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作者 JIANGMei WANGYunlong YUANQi CHENYaqu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2004年第2期329-336,共8页
Quantitative distribution of planktonic amphipoda in the East China Sea is analyzed and the relation with environmental factors and mackerel and scad fishing grounds is studied. The result shows that the characteristi... Quantitative distribution of planktonic amphipoda in the East China Sea is analyzed and the relation with environmental factors and mackerel and scad fishing grounds is studied. The result shows that the characteristic of biomass is great seasonal and interannual variety during the passing three decades. The distribution of planktonic amphipoda basically reflects the movement, decay and intensification of the different water systems in the survey area. 展开更多
关键词 East China Sea amphipoda biomass spatial and temporal distribution environmental factors mackerel and scad fishing grounds
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Spatial Distribution Pattern of the Steppe Toad-headed Lizard(Phrynocephalus frontalis) and Its Influencing Factors 被引量:1
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作者 Xue LIAN Zhigang JIANG +3 位作者 Xiaoge PING Songhua TANG Junhuai BI Chunwang LI 《Asian Herpetological Research》 SCIE 2012年第1期46-51,共6页
Spatial distribution patterns are associated with life history and behavioral adaptations of animals. For studying the spatial distribution pattern of the steppe toad-headed lizard(Phrynocephalus frontalis) and its in... Spatial distribution patterns are associated with life history and behavioral adaptations of animals. For studying the spatial distribution pattern of the steppe toad-headed lizard(Phrynocephalus frontalis) and its influencing factors,we conducted experiments in Hunshandake Sandy Land in Inner Mongolia,China in July 2009. By calculating the clustered indices,we found that the lizard was aggregately distributed when the sampling quadrat was smaller than 10 m × 10 m,and uniformly distributed when it was greater than 10 m × 10 m. The Nearest Neighbor Rule showed a clustering distribution pattern for P. frontalis and the distribution pattern was quadrat-sampling dependent. Furthermore,the cluster was determined by environmental factors when the sampling quadrat was smaller than 20 m × 20 m,but it was determined by both environmental factors and characteristics of the lizard when it was larger than 20 m × 20 m. Our results suggested that the steppe toad-headed lizards tended to aggregate into suitable habitat patches in desert areas. Additionally,we discussed that the lizard aggregation could be potentially used as an indictor of movement of sand dunes. 展开更多
关键词 sand lizard Phrynocephalus frontalis spatial distribution environmental factor quadrat-sampling effect
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Distributed sound source localization algorithm with sound velocity calibration in windy environments 被引量:3
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作者 YAN Qingli CHEN Jianfeng 《Chinese Journal of Acoustics》 CSCD 2018年第1期35-44,共10页
A new sound source localization method with sound speed compensation is proposed to reduce the wind influence on the performance of conventional TDOA (Time Difference of Arrival) algorithms. First, the sound speed i... A new sound source localization method with sound speed compensation is proposed to reduce the wind influence on the performance of conventional TDOA (Time Difference of Arrival) algorithms. First, the sound speed is described as a set of functions of the unknown source location, to approximate the acoustic velocity field distribution in the wind field. Then, they are introduced into the TDOA algorithm, to construct nonlinear equations. Finally, the particle swarm optimization algorithm is used to estimate the source location. The simulation results show that the proposed algorithm can significantly improve the localization accuracy for different wind velocities, source locations and test area sizes. The experimental results show that the proposed method can reduce localization errors to about 40% of the original error in a four nodes localization system. 展开更多
关键词 distributed sound source localization algorithm with sound velocity calibration in windy environments
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A Heuristic Algorithm to Solve the Task Partition Problem in MDOCEM
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作者 He Yan-xiang Chen Xin-mong +1 位作者 Donald H. Cooley Zhang Jian-ping 《Wuhan University Journal of Natural Sciences》 CAS 1999年第2期27-30,共4页
This paper examines task partition problem in a Multiagent based Distributed Open Computing Environment Model(MDOCEM). We first present a formal method to describe the task partition problem, then give a heuristic al... This paper examines task partition problem in a Multiagent based Distributed Open Computing Environment Model(MDOCEM). We first present a formal method to describe the task partition problem, then give a heuristic algorithm to solve the task partition problem that gives an approximate optimum solution. 展开更多
关键词 distributed open computing environment task partition planning management operation set
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