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An Experimental Study of Network-based Language Learning in Less-developed Areas
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作者 王正华 《海外英语》 2012年第12X期7-9,共3页
The advent of the Age of Information brings about bright prospects to Network-based Language Learning(NBLL).The thesis adopts the Engagement Theory as guided principles.The purpose is to use the novel NBLL model effec... The advent of the Age of Information brings about bright prospects to Network-based Language Learning(NBLL).The thesis adopts the Engagement Theory as guided principles.The purpose is to use the novel NBLL model effectively with the help of modern technology especially in less-developed areas.This thesis focuses on network-based experimental study.The research shows that the students under NBLL environment have cultivated the capabilities in information collection,computer operation,and information evaluation,as well as the abilities in problem solving,reasoning with criticism,and cooperating with others. 展开更多
关键词 the ENGAGEMENT theory network-baseD LANGUAGE LEARN
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Design for the simulation of space based information network 被引量:1
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作者 Zeng Bin Li Zitang Wang Wei 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第2期443-449,共7页
Ongoing research is described that is focused upon modelling the space base information network and simulating its behaviours: simulation of spaced based communications and networking project. Its objective is to dem... Ongoing research is described that is focused upon modelling the space base information network and simulating its behaviours: simulation of spaced based communications and networking project. Its objective is to demonstrate the feasibility of producing a tool that can provide a performance evaluation of various eonstellation access techniques and routing policies. The architecture and design of the simulation system are explored. The algorithm of data routing and instrument scheduling in this project is described. Besides these, the key methodologies of simulating the inter-satellite link features in the data transmissions are also discussed. The performance of both instrument scheduling algorithm and routing schemes is evaluated and analyzed through extensive simulations under a typical scenario. 展开更多
关键词 space based information network network simulation inter-satellite link routing scheduling simulation
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Feedback Scheduling of Model-based Networked Control Systems with Flexible Workload 被引量:4
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作者 Xian-Ming Tang Jin-Shou Yu 《International Journal of Automation and computing》 EI 2008年第4期389-394,共6页
In this paper,a novel control structure called feedback scheduling of model-based networked control systems is proposed to cope with a flexible network load and resource constraints.The state update time is adjusted a... In this paper,a novel control structure called feedback scheduling of model-based networked control systems is proposed to cope with a flexible network load and resource constraints.The state update time is adjusted according to the real-time network congestion situation.State observer is used under the situation where the state of the controlled plant could not be acquired.The stability criterion of the proposed structure is proved with time-varying state update time.On the basis of the stability of the novel system structure,the compromise between the control performance and the network utilization is realized by using feedback scheduler. Examples are provided to show the advantage of the proposed control structure. 展开更多
关键词 Model-based networked control system state update time stability criterion feedback scheduling.
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Node deployment strategy optimization for wireless sensor network with mobile base station 被引量:7
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作者 龙军 桂卫华 《Journal of Central South University》 SCIE EI CAS 2012年第2期453-458,共6页
The optimization of network performance in a movement-assisted data gathering scheme was studied by analyzing the energy consumption of wireless sensor network with node uniform distribution. A theoretically analytica... The optimization of network performance in a movement-assisted data gathering scheme was studied by analyzing the energy consumption of wireless sensor network with node uniform distribution. A theoretically analytical method for avoiding energy hole was proposed. It is proved that if the densities of sensor nodes working at the same time are alternate between dormancy and work with non-uniform node distribution. The efficiency of network can increase by several times and the residual energy of network is nearly zero when the network lifetime ends. 展开更多
关键词 网络节点 无线传感器 策略优化 移动基站 部署 剩余能量 传感器节点 网络性能
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A DYNAMIC SPECTRUM ACCESS NETWORK BASED ON COGNITIVE RADIO 被引量:2
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作者 Ren Pinyi Wang Jun Li Shaoqian 《Journal of Electronics(China)》 2010年第5期577-610,共34页
Dynamic spectrum access technologies based on Cognitive Radio(CR) is under intensive research carried out by the wireless communication society and is expected to solve the problem of spectrum scarcity.However,most en... Dynamic spectrum access technologies based on Cognitive Radio(CR) is under intensive research carried out by the wireless communication society and is expected to solve the problem of spectrum scarcity.However,most enabling technologies related to dynamic spectrum access are con-sidered individually.In this paper,we consider these key technologies jointly and introduce a new implementation scheme for a Dynamic Spectrum Access Network Based on Cognitive Radio(DSAN-BCR).We start with a flexible hardware platform for DSAN-BCR,as well as a flexible protocol structure that dominates the operation of DSAN-BCR.We then focus on the state of the art of key technologies such as spectrum sensing,spectrum resources management,dynamic spectrum access,and routing that are below the network layer in DSAN-BCR,as well as the development of technologies related to higher layers.Last but not the least,we analyze the challenges confronted by these men-tioned technologies in DSAN-BCR,and give the perspectives on the future development of these technologies.The DSAN-BCR introduced is expected to provide a system level guidance to alleviate the problem of spectrum scarcity. 展开更多
关键词 Cognitive Radio (CR) Dynamic Spectrum Access network based on Cognitive Radio (DSAN-BCR) Spectrum sensing Spectrum management Dynamic Spectrum Access (DSA) Cognitive routing
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Predictive Tracking Control of Network-Based Agents With Communication Delays 被引量:3
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作者 Tianyong Zhang Guoping Liu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2018年第6期1150-1156,共7页
This paper investigates the remote tracking control problem of Network-based Agents with communication delays existing in both forward and feedback communication channels.A networked predictive tracking controller is ... This paper investigates the remote tracking control problem of Network-based Agents with communication delays existing in both forward and feedback communication channels.A networked predictive tracking controller is proposed to compensate the negative effects caused by bilateral time-delays in a wireless network. Furthermore, the problem of consecutive data loss in the feedback channel is solved using aforementioned controller, where lateral movement perturbations are introduced.Simulations and experiments are provided for several cases,which verify the realizability and effectiveness of the proposed controller. 展开更多
关键词 反馈通信 信道 自动化技术 发展现状
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Immunizations on small worlds of tree-based wireless sensor networks 被引量:1
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作者 李峤 张百海 +2 位作者 崔灵果 范衠 Athanasios V.Vasilakos 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第5期25-33,共9页
The sensor virus is a serious threat,as an attacker can simply send a single packet to compromise the entire sensor network.Epidemics become drastic with link additions among sensors when the small world phenomena occ... The sensor virus is a serious threat,as an attacker can simply send a single packet to compromise the entire sensor network.Epidemics become drastic with link additions among sensors when the small world phenomena occur.Two immunization strategies,uniform immunization and temporary immunization,are conducted on small worlds of tree-based wireless sensor networks to combat the sensor viruses.With the former strategy,the infection extends exponentially,although the immunization effectively reduces the contagion speed.With the latter strategy,recurrent contagion oscillations occur in the small world when the spatial-temporal dynamics of the epidemic are considered.The oscillations come from the small-world structure and the temporary immunization.Mathematical analyses on the small world of the Cayley tree are presented to reveal the epidemic dynamics with the two immunization strategies. 展开更多
关键词 epidemic immunization small world tree-based networks
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Anomaly Detection of Complex Networks Based on Intuitionistic Fuzzy Set Ensemble 被引量:1
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作者 王进法 刘晓 +1 位作者 赵海 陈星池 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第5期156-160,共5页
Ensemble learning for anomaly detection of data structured into a complex network has been barely studied due to the inconsistent performance of complex network characteristics and the lack of inherent objective funct... Ensemble learning for anomaly detection of data structured into a complex network has been barely studied due to the inconsistent performance of complex network characteristics and the lack of inherent objective function. We propose the intuitionistic fuzzy set(IFS)-based anomaly detection, a new two-phase ensemble method for anomaly detection based on IFS, and apply it to the abnormal behavior detection problem in temporal complex networks.Firstly, it constructs the IFS of a single network characteristic, which quantifies the degree of membership,non-membership and hesitation of each network characteristic to the defined linguistic variables so that makes the unuseful or noise characteristics become part of the detection. To build an objective intuitionistic fuzzy relationship, we propose a Gaussian distribution-based membership function which gives a variable hesitation degree. Then, for the fuzzification of multiple network characteristics, the intuitionistic fuzzy weighted geometric operator is adopted to fuse multiple IFSs and to avoid the inconsistence of multiple characteristics. Finally, the score function and precision function are used to sort the fused IFS. Finally, we carry out extensive experiments on several complex network datasets for anomaly detection, and the results demonstrate the superiority of our method to state-of-the-art approaches, validating the effectiveness of our method. 展开更多
关键词 NET IFS Anomaly Detection of Complex networks based on Intuitionistic Fuzzy Set Ensemble
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On the model-based networked control for singularly perturbed systems 被引量:1
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作者 Hongwang YU Zhiming WANG Yufan ZHENG 《控制理论与应用(英文版)》 EI 2008年第2期153-162,共10页
In this paper, the control of a two-time-scale plant, where the sensor is connected to a linear controller/ actuator via a network is addressed. The slow and fast systems of singularly perturbed systems are used to pr... In this paper, the control of a two-time-scale plant, where the sensor is connected to a linear controller/ actuator via a network is addressed. The slow and fast systems of singularly perturbed systems are used to produce an estimate of the plant state behavior between transmission times, by which one can reduce the usage of the network. The approximate solutions of the whole systems are derived and it is shown that the whole systems via the network control are generally asymptotically stable as long as their slow and fast systems are both stable. These results are also extended to the case of network delay. 展开更多
关键词 Model-based networked control systems Singularly perturbed control systems Asymptotically stable Globally practical stability
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A Network-Based VPN Architecture Using Virtual Routing 被引量:4
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作者 ZHANG Bao-liang 1,2,HU Han-ping 1,2,WU Xiao-gang 1,2, KONG Tao 31.State Education Ministry Key Laboratory of Image Information and Intelligent Control, Wuhan 430074, Hubei, China 2.Institute of Pattem Recognition and Artificial Intelligonce, Huazhong University of Science and Technology, Wuhan 430074, Hubei, China 3.709th Research Institute of China Shipbuilding Engineering Society, Wuhan 430074, Hubei, China 《Wuhan University Journal of Natural Sciences》 CAS 2005年第1期161-164,共4页
A network-based Virtual Private Network (VPN) architecture by using fundamental routing mechanism is proposed. This network is a virtual overlay network based on the relay of IP-in-IP tunneling of virtual routing modu... A network-based Virtual Private Network (VPN) architecture by using fundamental routing mechanism is proposed. This network is a virtual overlay network based on the relay of IP-in-IP tunneling of virtual routing modules. The packet format employs the encapsulation of IPSec ESP(Encapsulating Security Payload), an impact path code and an extended DS(Differentiated Services) code to support multi-path routing and QoS. Comparing with other models of VPN, this network system can be deployed in the current network with little investment, and it is easy to implement. The simulation result shows its performance is better than the traditional VPN system of black box mode. 展开更多
关键词 virtual routing network-based VPN proactive defense
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Real-valued multi-area self set optimization in immunity-based network intrusion detection system 被引量:1
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作者 Zhang Fengbin Xi Liang Wang Shengwen 《High Technology Letters》 EI CAS 2012年第1期1-6,共6页
关键词 网络入侵检测系统 优化算法 区域自治 免疫 高斯分布 发电效率 分布理论 聚类算法
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APPLICATION OF ARCHITECTURE- BASED NEURAL NETWORKS IN MODELING AND PARAMETER OPTIMIZATION OF HYDRAULIC BUMPER 被引量:1
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作者 Yang Haiwei Zhan Yongqi Qiao Junwei Shi GuanglinSchool of Mechanical Engineering,Shanghai Jiaotong University,Shanghai 200030, China 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2003年第3期313-316,共4页
The dynamic working process of 52SFZ-140-207B type of hydraulic bumper isanalyzed. The modeling method using architecture-based neural networks is introduced. Using thismodeling method, the dynamic model of the hydrau... The dynamic working process of 52SFZ-140-207B type of hydraulic bumper isanalyzed. The modeling method using architecture-based neural networks is introduced. Using thismodeling method, the dynamic model of the hydraulic bumper is established; Based on this model thestructural parameters of the hydraulic bumper are optimized with Genetic algorithm. The result showsthat the performance of the dynamic model is close to that of the hydraulic bumper, and the dynamicperformance of the hydraulic bumper is improved through parameter optimization. 展开更多
关键词 Architecture-based Neural networks MODELING Parameter optimization Hydraulic bumper
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An SDN/NFV Based Framework for Management and Deployment of Service Based 5G Core Network 被引量:22
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作者 Lu Ma Xiangming Wen +2 位作者 Luhan Wang Zhaoming Lu Raymond Knopp 《China Communications》 SCIE CSCD 2018年第10期86-98,共13页
The traffic explosion and the rising of diverse requirements lead to many challenges for traditional mobile network architecture on flexibility, scalability, and deployability. To meet new requirements in the 5 G era,... The traffic explosion and the rising of diverse requirements lead to many challenges for traditional mobile network architecture on flexibility, scalability, and deployability. To meet new requirements in the 5 G era, service based architecture is introduced into mobile networks. The monolithic network elements(e.g., MME, PGW, etc.) are split into smaller network functions to provide customized services. However, the management and deployment of network functions in service based 5 G core network are still big challenges. In this paper, we propose a novel management architecture for 5 G service based core network based on NFV and SDN. Combined with SDN, NFV and edge computing, the proposed framework can provide distributed and on-demand deployment of network functions, service guaranteed network slicing, flexible orchestration of network functions and optimal workload allocation. Simulations are conducted to show that the proposed framework and algorithm are effective in terms of reducing network operating cost. 展开更多
关键词 管理体系结构 核心网络 服务 框架 网络函数 活动网络 可伸缩性 网络元素
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Experts' Knowledge Fusion in Model-Based Diagnosis Based on Bayes Networks 被引量:5
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作者 Deng Yong & Shi Wenkang School of Electronics & Information Technology, Shanghai Jiaotong University, Shanghai 200030, P. R. China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2003年第2期25-30,共6页
In previous researches on a model-based diagnostic system, the components are assumed mutually independent. Howerver , the assumption is not always the case because the information about whether a component is faulty ... In previous researches on a model-based diagnostic system, the components are assumed mutually independent. Howerver , the assumption is not always the case because the information about whether a component is faulty or not usually influences our knowledge about other components. Some experts may draw such a conclusion that 'if component m 1 is faulty, then component m 2 may be faulty too'. How can we use this experts' knowledge to aid the diagnosis? Based on Kohlas's probabilistic assumption-based reasoning method, we use Bayes networks to solve this problem. We calculate the posterior fault probability of the components in the observation state. The result is reasonable and reflects the effectiveness of the experts' knowledge. 展开更多
关键词 Model-based diagnosis Experts' knowledge Probabilistic assumption-based reasoning Bayes networks.
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Adaptive swarm-based routing in communication networks 被引量:2
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作者 吕勇 赵光宙 +1 位作者 苏凡军 历小润 《Journal of Zhejiang University Science》 EI CSCD 2004年第7期867-872,共6页
Swarm intelligence inspired by the social behavior of ants boasts a number of attractive features, including adaptation, robustness and distributed, decentralized nature, which are well suited for routing in modern co... Swarm intelligence inspired by the social behavior of ants boasts a number of attractive features, including adaptation, robustness and distributed, decentralized nature, which are well suited for routing in modern communication networks. This paper describes an adaptive swarm-based routing algorithm that increases convergence speed, reduces routing instabilities and oscillations by using a novel variation of reinforcement learning and a technique called momentum.Experiment on the dynamic network showed that adaptive swarm-based routing learns the optimum routing in terms of convergence speed and average packet latency. 展开更多
关键词 通信网络 集群智能 自适应集群基路径算法 蚂蚁算法 收敛速度
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Computer vision-based limestone rock-type classification using probabilistic neural network 被引量:15
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作者 Ashok Kumar Patel Snehamoy Chatterjee 《Geoscience Frontiers》 SCIE CAS CSCD 2016年第1期53-60,共8页
Proper quality planning of limestone raw materials is an essential job of maintaining desired feed in cement plant. Rock-type identification is an integrated part of quality planning for limestone mine. In this paper,... Proper quality planning of limestone raw materials is an essential job of maintaining desired feed in cement plant. Rock-type identification is an integrated part of quality planning for limestone mine. In this paper, a computer vision-based rock-type classification algorithm is proposed for fast and reliable identification without human intervention. A laboratory scale vision-based model was developed using probabilistic neural network(PNN) where color histogram features are used as input. The color image histogram-based features that include weighted mean, skewness and kurtosis features are extracted for all three color space red, green, and blue. A total nine features are used as input for the PNN classification model. The smoothing parameter for PNN model is selected judicially to develop an optimal or close to the optimum classification model. The developed PPN is validated using the test data set and results reveal that the proposed vision-based model can perform satisfactorily for classifying limestone rocktypes. Overall the error of mis-classification is below 6%. When compared with other three classification algorithms, it is observed that the proposed method performs substantially better than all three classification algorithms. 展开更多
关键词 Supervised classification Probabilistic neural network Histogram based features Smoothing parameter LIMESTONE
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A precise tidal prediction mechanism based on the combination of harmonic analysis and adaptive network-based fuzzy inference system model 被引量:6
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作者 ZHANG Zeguo YIN Jianchuan +2 位作者 WANG Nini HU Jiangqiang WANG Ning 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第11期94-105,共12页
An efficient and accurate prediction of a precise tidal level in estuaries and coastal areas is indispensable for the management and decision-making of human activity in the field wok of marine engineering. The variat... An efficient and accurate prediction of a precise tidal level in estuaries and coastal areas is indispensable for the management and decision-making of human activity in the field wok of marine engineering. The variation of the tidal level is a time-varying process. The time-varying factors including interference from the external environment that cause the change of tides are fairly complicated. Furthermore, tidal variations are affected not only by periodic movement of celestial bodies but also by time-varying interference from the external environment. Consequently, for the efficient and precise tidal level prediction, a neuro-fuzzy hybrid technology based on the combination of harmonic analysis and adaptive network-based fuzzy inference system(ANFIS)model is utilized to construct a precise tidal level prediction system, which takes both advantages of the harmonic analysis method and the ANFIS network. The proposed prediction model is composed of two modules: the astronomical tide module caused by celestial bodies’ movement and the non-astronomical tide module caused by various meteorological and other environmental factors. To generate a fuzzy inference system(FIS) structure,three approaches which include grid partition(GP), fuzzy c-means(FCM) and sub-clustering(SC) are used in the ANFIS network constructing process. Furthermore, to obtain the optimal ANFIS based prediction model, large numbers of simulation experiments are implemented for each FIS generating approach. In this tidal prediction study, the optimal ANFIS model is used to predict the non-astronomical tide module, while the conventional harmonic analysis model is used to predict the astronomical tide module. The final prediction result is performed by combining the estimation outputs of the harmonious analysis model and the optimal ANFIS model. To demonstrate the applicability and capability of the proposed novel prediction model, measured tidal level samples of Fort Pulaski tidal station are selected as the testing database. Simulation and experimental results confirm that the proposed prediction approach can achieve precise predictions for the tidal level with high accuracy, satisfactory convergence and stability. 展开更多
关键词 tidal level prediction harmonious analysis method adaptive network-based fuzzy inference system correlation analysis
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Range-Based Localization in Wireless Networks Using Density-Based Outlier Detection 被引量:2
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作者 Khalid K. Almuzaini Aaron Gulliver 《Wireless Sensor Network》 2010年第11期807-814,共8页
Node localization is commonly employed in wireless networks. For example, it is used to improve routing and enhance security. Localization algorithms can be classified as range-free or range-based. Range-based algorit... Node localization is commonly employed in wireless networks. For example, it is used to improve routing and enhance security. Localization algorithms can be classified as range-free or range-based. Range-based algorithms use location metrics such as ToA, TDoA, RSS, and AoA to estimate the distance between two nodes. Proximity sensing between nodes is typically the basis for range-free algorithms. A tradeoff exists since range-based algorithms are more accurate but also more complex. However, in applications such as target tracking, localization accuracy is very important. In this paper, we propose a new range-based algorithm which is based on the density-based outlier detection algorithm (DBOD) from data mining. It requires selection of the K-nearest neighbours (KNN). DBOD assigns density values to each point used in the location estimation. The mean of these densities is calculated and those points having a density larger than the mean are kept as candidate points. Different performance measures are used to compare our approach with the linear least squares (LLS) and weighted linear least squares based on singular value decomposition (WLS-SVD) algorithms. It is shown that the proposed algorithm performs better than these algorithms even when the anchor geometry about an unlocalized node is poor. 展开更多
关键词 LOCALIZATION POSITIONING Ad HOC networks Range-based Wireless Sensor network OUTLIER Detection CLUSTERING
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Probe on Network-based Collaborative Maintenance Model for After-sales Equipment 被引量:2
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作者 CHEN Xiaohui SHENG Tianwen YI Shuping 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2009年第5期702-709,共8页
In order to make equipment run safely, economically and continuously, some new maintenance models were put forward to improve the equipment after-sale maintenance service, such as E-maintenance, third-party maintenanc... In order to make equipment run safely, economically and continuously, some new maintenance models were put forward to improve the equipment after-sale maintenance service, such as E-maintenance, third-party maintenance, etc. To certain extent, the models solved the problem of the distance between the manufacturer and customer and the dispersion of the maintenance technologies, however, those resources are still widely distributed and do not collaborate efficiently. In this paper, a network-based collaborative maintenance service model was proposed for after-sales equipment to solve the problem of maintenance resources integration. Concretely, equipment designers, maintainers, spare parts suppliers and maintenance experts were grouped together to establish dynamic alliance. The leader of the alliance is the manufacturer under guaranty period or equipment user exceeding the guaranty period. The process of maintenance service was divided into three stages which are fault diagnosis, maintenance decision and maintenance implementation. The sub-alliances were established to carry out maintenance work at each stage. In addition, the business process of network-based collaborative maintenance was analyzed and collaborative business system for equipment's after-sales collaborative maintenance service was designed. In the end, an informational economics model of network-based collaborative maintenance was established to demonstrate the effectiveness of this maintenance model. 展开更多
关键词 network-based collaborative maintenance after-sales service dynamic maintenance alliance information economics
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Triplet Label Based Image Retrieval Using Deep Learning in Large Database 被引量:1
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作者 K.Nithya V.Rajamani 《Computer Systems Science & Engineering》 SCIE EI 2023年第3期2655-2666,共12页
Recent days,Image retrieval has become a tedious process as the image database has grown very larger.The introduction of Machine Learning(ML)and Deep Learning(DL)made this process more comfortable.In these,the pair-wi... Recent days,Image retrieval has become a tedious process as the image database has grown very larger.The introduction of Machine Learning(ML)and Deep Learning(DL)made this process more comfortable.In these,the pair-wise label similarity is used tofind the matching images from the database.But this method lacks of limited propose code and weak execution of misclassified images.In order to get-rid of the above problem,a novel triplet based label that incorporates context-spatial similarity measure is proposed.A Point Attention Based Triplet Network(PABTN)is introduced to study propose code that gives maximum discriminative ability.To improve the performance of ranking,a corre-lating resolutions for the classification,triplet labels based onfindings,a spatial-attention mechanism and Region Of Interest(ROI)and small trial information loss containing a new triplet cross-entropy loss are used.From the experimental results,it is shown that the proposed technique exhibits better results in terms of mean Reciprocal Rank(mRR)and mean Average Precision(mAP)in the CIFAR-10 and NUS-WIPE datasets. 展开更多
关键词 Image retrieval deep learning point attention based triplet network correlating resolutions classification region of interest
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