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Aspect-Level Sentiment Analysis Incorporating Semantic and Syntactic Information
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作者 Jiachen Yang Yegang Li +2 位作者 Hao Zhang Junpeng Hu Rujiang Bai 《Journal of Computer and Communications》 2024年第1期191-207,共17页
Aiming at the problem that existing models in aspect-level sentiment analysis cannot fully and effectively utilize sentence semantic and syntactic structure information, this paper proposes a graph neural network-base... Aiming at the problem that existing models in aspect-level sentiment analysis cannot fully and effectively utilize sentence semantic and syntactic structure information, this paper proposes a graph neural network-based aspect-level sentiment classification model. Self-attention, aspectual word multi-head attention and dependent syntactic relations are fused and the node representations are enhanced with graph convolutional networks to enable the model to fully learn the global semantic and syntactic structural information of sentences. Experimental results show that the model performs well on three public benchmark datasets Rest14, Lap14, and Twitter, improving the accuracy of sentiment classification. 展开更多
关键词 Aspect-level Sentiment Analysis Attentional Mechanisms Dependent Syntactic Trees Graph Convolutional Neural networks
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Relationship Between Changes of River-lake Networks and Water Levels in Typical Regions of Taihu Lake Basin,China 被引量:6
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作者 YIN Yixing XU Youpeng CHEN Ying 《Chinese Geographical Science》 SCIE CSCD 2012年第6期673-682,共10页
The typical regions of the Taihu Lake Basin,China,were selected to analyze the variation characteristics of river-lake networks under intensive human activities.The characteristics of the fractal dimension of river ne... The typical regions of the Taihu Lake Basin,China,were selected to analyze the variation characteristics of river-lake networks under intensive human activities.The characteristics of the fractal dimension of river networks and lakes for different periods were investigated and the influences of river system evolution on water level changes were further explored through the comparison of their fractal characters.The results are as follows:1) River network development of the study area is becoming more monotonous and more simple;the number of lakes is reducing significantly,and the water surface ratio has dropped significantly since the 1980s.2) The box dimension of the river networks in all the cities of the study area decreased slowly from the 1960s to the 1980s,while the decrease was significant from the 1980s to the 2000s.The variations of lake correlation dimension are similar to those of the river network box dimensions.This is unfavorable for the storage capacity of the river networks and lakes.3) The Hurst exponents of water levels were all between 0.5 and 1.0 from the 1960s to the 1980s,while decreased in the 2000s,indicating the decline in persistence and increase in the complexity of water level series.The paper draws a conclusion that the relationship between the fractal dimension of river-lake networks and the Hurst exponents of the water level series can reveal the impacts of river system changes on flood disasters to some extent:the disappearance of river networks and lakes will increase the possibility of flood occurrence. 展开更多
关键词 水位变化 太湖流域 网络 典型地区 江湖 中国 HURST指数 分形维数
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Application of Neural network PID Controller in Constant Temper-ature and Constant Liquid-level System 被引量:11
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作者 (College of information and control engineering, University of Petroleum, Dongying 257061, China) Chen Guochu Hao Ninmei Liu Xianguang(College of electricity engineering, University of Xi ’ an Communication, Xi’ an 710049, China) Zhang Lin (Workshop of Instrument of Plastic Plant, Qilu Petrochemical Corp., Zibo 255411, China) Wang Junhong 《微计算机信息》 2003年第1期23-24,42,共3页
Guided by the principle of neural network, an intelligent PID controller based on neural network is devised and applied to control of constant temperature and constant liquidlevel system. The experiment results show t... Guided by the principle of neural network, an intelligent PID controller based on neural network is devised and applied to control of constant temperature and constant liquidlevel system. The experiment results show that this controller has high accuracy and strong robustness and good characters. 展开更多
关键词 PID控制器 神经网络 PID控制 恒温恒液位系统
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Towards efficient deep neural network training by FPGA-based batch-level parallelism 被引量:4
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作者 Cheng Luo Man-Kit Sit +3 位作者 Hongxiang Fan Shuanglong Liu Wayne Luk Ce Guo 《Journal of Semiconductors》 EI CAS CSCD 2020年第2期51-62,共12页
Training deep neural networks(DNNs)requires a significant amount of time and resources to obtain acceptable results,which severely limits its deployment in resource-limited platforms.This paper proposes DarkFPGA,a nov... Training deep neural networks(DNNs)requires a significant amount of time and resources to obtain acceptable results,which severely limits its deployment in resource-limited platforms.This paper proposes DarkFPGA,a novel customizable framework to efficiently accelerate the entire DNN training on a single FPGA platform.First,we explore batch-level parallelism to enable efficient FPGA-based DNN training.Second,we devise a novel hardware architecture optimised by a batch-oriented data pattern and tiling techniques to effectively exploit parallelism.Moreover,an analytical model is developed to determine the optimal design parameters for the DarkFPGA accelerator with respect to a specific network specification and FPGA resource constraints.Our results show that the accelerator is able to perform about 10 times faster than CPU training and about a third of the energy consumption than GPU training using 8-bit integers for training VGG-like networks on the CIFAR dataset for the Maxeler MAX5 platform. 展开更多
关键词 deep neural network TRAINING FPGA batch-level parallelism
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Research on confirmation of basic technological parameters of tension levellers based on neural network and genetic algorithm
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作者 彭晓晖 徐宏喆 +2 位作者 李盼 王社昌 任玉成 《Journal of Pharmaceutical Analysis》 SCIE CAS 2008年第3期160-163,177,共5页
Confirmation of basic technological parameters of tension levellers is the most important factor of leveling strip. Up to now, most factories have used experts’ experience to decide these parameters, without any esta... Confirmation of basic technological parameters of tension levellers is the most important factor of leveling strip. Up to now, most factories have used experts’ experience to decide these parameters, without any established rule to follow. For better quality of strip, a valid method is needed to decide technological parameters precisely and reasonably. In this paper, a method is used based on neural network and genetic algorithm. Neural network has a good ability to extract rules from work process of tension levellers. Then using neural network, which has learned from a lot of working samples, to be the evaluation of fitness, genetic algorithm could easily find the best or better technological parameters. At the end of this paper, examinations are given to show the effect of this method. 展开更多
关键词 tension levellers neural network genetic algorithm strip flatness
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Groundwater Level Prediction Using Artificial Neural Networks: A Case Study in Tra Noc Industrial Zone, Can Tho City, Vietnam 被引量:2
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作者 Tran Van Ty Le Van Phat Huynh Van Hiep 《Journal of Water Resource and Protection》 2018年第9期870-883,共14页
The objective of this study is to predict groundwater levels (GWLs) under different impact factors using Artificial Neural Network (ANN) for a case study in Tra Noc Industrial Zone, Can Tho City, Vietnam. This can be ... The objective of this study is to predict groundwater levels (GWLs) under different impact factors using Artificial Neural Network (ANN) for a case study in Tra Noc Industrial Zone, Can Tho City, Vietnam. This can be achieved by evaluating the current state of groundwater resources (GWR) exploitation, use and dynamics;setting-up, calibrating and validating the ANN;and then predicting GWLs at different lead times. The results show that GWLs in the study area have been found to reduce rapidly from 2000 to 2015, especially in the Middle-upper Pleistocene (qp2-3) and upper Pleistocene (qp3) due to the over-withdrawals from the enterprises for production purposes. Concerning this problem, an Official Letter of the People’s Committee of Can Tho City was issued and taken into enforcement in 2012 resulting in the reduction of exploitation. The calibrated ANN structures have successfully demonstrated that the GWLs can be predicted considering different impact factors. The predicted results will help to raise awareness and to draw an attention of the local/central government for a clear GWR management policy for the Mekong delta, especially the industrial zones in the urban areas such as Can Tho city. 展开更多
关键词 GROUNDWATER Resources (GWR) GROUNDWATER levels (GWLs) Artificial Neural network (ANN) Prediction TRA NOC Industrial Zone
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Monitoring Efficiency Evaluation of the Well-water-level Observation Network in China
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作者 Liu Chunguo Kong Lingchang +2 位作者 Yang Zhuzhuan Fan Chunyan Chen Huajing 《Earthquake Research in China》 CSCD 2016年第1期88-99,共12页
In order to understand the monitoring efficiency status of the well-water-level observation network in China after the completion of the 10 th "Five-year Plan " digital network project,and to provide a basis... In order to understand the monitoring efficiency status of the well-water-level observation network in China after the completion of the 10 th "Five-year Plan " digital network project,and to provide a basis for the future network optimization and equipment updating, the monitoring efficiency of the well-water-level observation network was evaluated. On the whole,61. 8% observing stations have good monitoring effectiveness,the observation environment of 73. 5% of observing stations meets the monitoring requirements of well-water-level. The operation status of the network is as a whole getting better,operation rates of 75% observing instruments are above 95%. Most well water levels can monitor crustal stress changes and seismic activities. However,some observation stations,due to inherent deficiency in wells,environmental disturbance,instrument aging,and low-level operation and maintenance,need to improve the monitoring efficiency level by taking measures such as observation environment improvement,equipment updating,and management training. About 6. 5% of the stations need to stop observation due to the unqualified observational environment. 展开更多
关键词 水位监测 观测网络 井水位 评价 设备更新 网络优化 观测环境 观测仪器
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Artificial Neural Network Modeling of Healthy Risk Level Induced by Aircraft Pollutant Impacts around Soekarno Hatta International Airport 被引量:1
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作者 Salah Khardi Jermanto Setia Kurniawan +1 位作者 Irwan Katili Setyo Moersidik 《Journal of Environmental Protection》 2013年第8期28-39,共12页
Aircraft pollutant emissions are an important part of sources of pollution that directly or indirectly affect human health and ecosystems. This research suggests an Artificial Neural Network model to determine the hea... Aircraft pollutant emissions are an important part of sources of pollution that directly or indirectly affect human health and ecosystems. This research suggests an Artificial Neural Network model to determine the healthy risk level around Soekarno Hatta International Airport-Cengkareng Indonesia. This ANN modeling is a flexible method, which enables to recognize highly complex non-linear correlations. The network was trained with real measurement data and updated with new measurements, enhancing its quality and making it the ideal method for this research. Measurements of aircraft pollutant emissions are carried out with the aim to be used as input data and to validate the developed model. The obtained results concerned the improved ANN architecture model based on pollutant emissions as input variables. ANN model processes variables—hidden layers—and gives an output variable corresponding to a healthy risk level. This model is characterized by a 4-10-1 scheme. Based on ANN criteria, the best validation performance is achieved at epoch 28 from 34 epochs with the Mean Squared Error (MSE) of 9 × 10-3. The correlation between targets and outputs is confirmed. It validated a close relationship between targets and outputs. The network output errors value approaches zero. Further research is needed with the aim to enlarge the scheme of the ANN model by increasing its input variables. This is one of the major key defining environmental capacities of an airport that should be applied by Indonesian airport authorities. These would institute policies to manage or reduce pollutant emissions considering population and income growth to be socially positive. 展开更多
关键词 AIRCRAFT POLLUTANT Emissions Artificial Neural network HEALTHY Risk level
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Groundwater level prediction based on hybrid hierarchy genetic algorithm and RBF neural network 被引量:1
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作者 屈吉鸿 黄强 +1 位作者 陈南祥 徐建新 《Journal of Coal Science & Engineering(China)》 2007年第2期170-174,共5页
关键词 混合分层遗传算法 RBF神经网络 地下水位 预测模型
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Parameter Method Data Processing for CPⅢ Precise Trigonometric Leveling Network
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作者 Jianzhang LI Haowen YAN 《Journal of Geodesy and Geoinformation Science》 2020年第3期67-75,共9页
In view of the limitation of the difference method,the adjustment model of CPⅢprecise trigonometric leveling control network based on the parameter method was proposed in the present paper.The experiment results show... In view of the limitation of the difference method,the adjustment model of CPⅢprecise trigonometric leveling control network based on the parameter method was proposed in the present paper.The experiment results show that this model has a simple algorithm and high data utilization,avoids the negative influences caused by the correlation among the data acquired from the difference method and its accuracy is improved compared with the difference method.In addition,the strict weight of CPⅢprecise trigonometric leveling control network was also discussed in this paper.The results demonstrate that the ranging error of trigonometric leveling can be neglected when the vertical angle is less than 3 degrees.The accuracy of CPⅢprecise trigonometric leveling control network has not changed significantly before and after strict weight. 展开更多
关键词 CPⅢleveling control network precise trigonometric leveling parameter method minimum norm quadratic unbiased estimate
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Reducing the Short Circuit Levels in Kuwait Transmission Network
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作者 W. AI-Hasawi M. Gilany 《Journal of Energy and Power Engineering》 2010年第5期45-51,共7页
关键词 短路电流 传输网 科威特 网络管理 电流限制器 电力系统 数值模拟
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Network Traffic Generation Based on Statistical Packet-Level Characteristics
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作者 WANG Dongbin ZHUO Weihan +2 位作者 ZHANG Junhui WU Kexin OUYANG Wen 《China Communications》 SCIE CSCD 2015年第S2期144-148,共5页
Network traffic is very important for testing network equipment, network services, and security products. A new method of generating traffic based on statistical packet-level characteristics is proposed. In every time... Network traffic is very important for testing network equipment, network services, and security products. A new method of generating traffic based on statistical packet-level characteristics is proposed. In every time unit, the generator determines the sent packets number, the type and size of every sent packet according to the statistical characteristics of the original traffic. Then every packet, in which the protocol headers of transport layer, network layer and ethernet layer are encapsulated, is sent via the responding network interface card in the time unit. The results in the experiment show that the correlation coefficients between the bandwidth, the packet number, packet size distribution, the fragment number of the generated network traffic and those of the original traffic are all more than 0.96. The generated traffic and original traffic are very highly related and similar. 展开更多
关键词 network TRAFFIC GENERATION packet-level TRAFFIC CHARACTERISTICS
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Robust Synchronization in an E/I Network with Medium Synaptic Delay and High Level of Heterogeneity
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作者 韩芳 王直杰 +1 位作者 范宏 龚涛 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第4期25-28,共4页
It is known that both excitatory and inhibitory neuronal networks can achieve robust synchronization only under certain conditions, such as long synaptic delay or low level of heterogeneity. In this work, robust synch... It is known that both excitatory and inhibitory neuronal networks can achieve robust synchronization only under certain conditions, such as long synaptic delay or low level of heterogeneity. In this work, robust synchronization can be found in an excitatory/inhibitory (E/I) neuronal network with medium synaptie delay and high level of heterogeneity, which often occurs in real neuronal networks. Two effects of post-synaptic potentials (PSP) to network synchronization are presented, and the synaptic contribution of excitatory and inhibitory neurons to robust synchronization in this E/I network is investigated. It is found that both excitatory and inhibitory neurons may contribute to robust synchronization in E/I networks, especially the excitatory PSP has a more positive effect on synchronization in E/I networks than that in excitatory networks. This may explain the strong robustness of synchronization in Eli neuronal networks. 展开更多
关键词 PSP Robust Synchronization in an E/I network with Medium Synaptic Delay and High level of Heterogeneity
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CMLP: Exploiting Caches at Multiple Levels of Proxies to Enhance Seamless Mobility Support in Information-Centric Networks
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作者 Haoqiu Huang Lanlan Rui +2 位作者 Weiwei Zheng Danmei Niu Xuesong Qiu 《China Communications》 SCIE CSCD 2016年第10期86-107,共22页
The recent evolution of the Internet towards "Information-centric" transfer modes has renewed the interest in exploiting proxies to enhance seamless mobility. In this work, we focus on the case of multiple l... The recent evolution of the Internet towards "Information-centric" transfer modes has renewed the interest in exploiting proxies to enhance seamless mobility. In this work, we focus on the case of multiple levels of proxies in ICN architectures, in which content requests from mobile subscribers and the corresponding items are proactively cached to these proxies at different levels. Specifically, we present a multiple-level proactive caching model that selects the appropriate subset of proxies at different levels and supports distributed online decision procedures in terms of the tradeoff between delay and cache cost. We show via extensive simulations the reduction of up to 31.63% in the total cost relative to Full Caching, in which caching in all 1-level neighbor proxies is performed, and up to 84.21% relative to No Caching, in which no caching is used. Moreover, the proposed model outperforms other approaches with a flat cache structure in terms of the total cost. 展开更多
关键词 Information-centric networking mobility multiple levels of proxies PUBLISH-SUBSCRIBE
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High-Level Portable Programming Language for Optimized Memory Use of Network Processors
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作者 Yasusi Kanada 《Communications and Network》 2015年第1期55-69,共15页
Network processors (NPs) are widely used for programmable and high-performance networks;however, the programs for NPs are less portable, the number of NP program developers is small, and the development cost is high. ... Network processors (NPs) are widely used for programmable and high-performance networks;however, the programs for NPs are less portable, the number of NP program developers is small, and the development cost is high. To solve these problems, this paper proposes an open, high-level, and portable programming language called “Phonepl”, which is independent from vendor-specific proprietary hardware and software but can be translated into an NP program with high performance especially in the memory use. A common NP hardware feature is that a whole packet is stored in DRAM, but the header is cached in SRAM. Phonepl has a hardware-independent abstraction of this feature so that it allows programmers mostly unconscious of this hardware feature. To implement the abstraction, four representations of packet data type that cover all the packet operations (including substring, concatenation, input, and output) are introduced. Phonepl have been implemented on Octeon NPs used in plug-ins for a network-virtualization environment called the VNode Infrastructure, and several packet-handling programs were evaluated. As for the evaluation result, the conversion throughput is close to the wire rate, i.e., 10 Gbps, and no packet loss (by cache miss) occurs when the packet size is 256 bytes or larger. 展开更多
关键词 network PROCESSORS PORTABILITY HIGH-level Language Hardware Independence MEMORY Usage DRAM SRAM network Virtualization
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Analysis of Lifetime of Large Wireless Sensor Networks Based on Multiple Battery Levels
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作者 Ruihua ZHANG Zhiping JIA Dongfeng YUAN 《International Journal of Communications, Network and System Sciences》 2008年第2期136-143,共8页
Due to the limited transmission range, data sensed by each sensor has to be forwarded in a multi-hop fashion before being delivered to the sink. The sensors closer to the sink have to forward comparatively more messag... Due to the limited transmission range, data sensed by each sensor has to be forwarded in a multi-hop fashion before being delivered to the sink. The sensors closer to the sink have to forward comparatively more messages than sensors at the periphery of the network,and will deplete their batteries earlier. Besides the loss of the sensing capabilities of the nodes close to the sink, a more serious consequence of the death of the first tier of sensor nodes is the loss of connectivity between the nodes at the periphery of the network and the sink;it makes the wireless networks expire. To alleviate this undesired effect and maximize the useful lifetime of the network, we investigate the energy consumption of different tiers and the effect of multiple battery levels, and demonstrate an attractively simple scheme to redistribute the total energy budget in multiple battery levels by data traffic load. We show by theoretical analysis, as well as simulation, that this substantially improves the network lifetime. 展开更多
关键词 WIRELESS Sensor networks Energy Efficient network LIFETIME BATTERY level
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Water level updating model for flow calculation of river networks
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作者 Xiao-ling WU Xiao-hua XIANG +1 位作者 Li LI Chuan-hai WANG 《Water Science and Engineering》 EI CAS CSCD 2014年第1期60-69,共10页
Complex water movement and insufficient observation stations are the unfavorable factors in improving the accuracy of flow calculation of river networks. A water level updating model for river networks was set up base... Complex water movement and insufficient observation stations are the unfavorable factors in improving the accuracy of flow calculation of river networks. A water level updating model for river networks was set up based on a three-step method at key nodes, and model correction values were collected from gauge stations. To improve the accuracy of water level and discharge forecasts for the entire network, the discrete coefficients of the Saint-Venant equations for river sections were regarded as the media carrying the correction values from observation locations to other cross-sections of the river network system. To examine the applicability, the updating model was applied to flow calculation of an ideal river network and the Chengtong section of the Yangtze River. Comparison of the forecast results with the observed data demonstrates that this updating model can improve the forecast accuracy in both ideal and real river networks. 展开更多
关键词 plain river network cyclic looped channel network water level updating model hydrodynamic model error correction
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Neural Network Based Multi-level Fuzzy Evaluation Model for Mechanical Kinematic Scheme
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作者 BO Ruifeng,LI Ruiqin (Department of Mechanical Engineering,North University of China,Taiyuan 030051,China) 《武汉理工大学学报》 CAS CSCD 北大核心 2006年第S1期301-306,共6页
To implement a quantificational evaluation for mechanical kinematic scheme more effectively,a multi-level and multi-objective evaluation model is presented using neural network and fuzzy theory. Firstly,the structure ... To implement a quantificational evaluation for mechanical kinematic scheme more effectively,a multi-level and multi-objective evaluation model is presented using neural network and fuzzy theory. Firstly,the structure of evaluation model is constructed according to evaluation indicator system. Then evaluation samples are generated and provided to train this model. Thus it can reflect the relation between attributive value and evaluation result,as well as the weight of evaluation indicator. Once evaluation indicators of each candidate are fuzzily quantified and fed into the trained network model,the corresponding evaluation result is outputted and the best alternative can be selected. Under this model,expert knowledge can be effectively acquired and expressed,and the quantificational evaluation can be implemented for kinematic scheme with multi-level evaluation indicator system. Several key problems on this model are discussed and an illustration has demonstrated that this model is feasible and can be regarded as a new idea for solving kinematic scheme evaluation. 展开更多
关键词 NEURAL network mechanical KINEMATIC SCHEME MULTI-level evaluation model FUZZY
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Strategies Regarding Operating Voltage Levels in Distribution Networks
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作者 G. Grigoras G. Cartina 《Journal of Energy and Power Engineering》 2010年第6期60-63,共4页
关键词 电网运行 电压水平 技术改进 优化网络 电压等级 城市配电网 能量损失 配电系统
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Correlation methods of base-level cycle based on wavelet neural network
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作者 Xingke XU Changwei CHEN Jing SUN Qinglong MENG 《Global Geology》 2007年第1期25-28,共4页
The authors discussed the method of wavelet neural network(WNN) for correlation of base-level cycle.A new vectored method of well log data was proposed.Through the training with the known data set,the WNN can remenber... The authors discussed the method of wavelet neural network(WNN) for correlation of base-level cycle.A new vectored method of well log data was proposed.Through the training with the known data set,the WNN can remenber the cycle pattern characteristic of the well log curves.By the trained WNN to identify the cycle pattern in the vectored log data,the ocrrelation process among the well cycles was completed.The application indicates that it is highly efficient and reliable in base-level cycle correlation. 展开更多
关键词 子波神经系统网络 地层学相关性 带齿三角带 基准面旋回划分
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