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Research on Tensor Multi-Clustering Distributed Incremental Updating Method for Big Data
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作者 Hongjun Zhang Zeyu Zhang +3 位作者 Yilong Ruan Hao Ye Peng Li Desheng Shi 《Computers, Materials & Continua》 SCIE EI 2024年第10期1409-1432,共24页
The scale and complexity of big data are growing continuously,posing severe challenges to traditional data processing methods,especially in the field of clustering analysis.To address this issue,this paper introduces ... The scale and complexity of big data are growing continuously,posing severe challenges to traditional data processing methods,especially in the field of clustering analysis.To address this issue,this paper introduces a new method named Big Data Tensor Multi-Cluster Distributed Incremental Update(BDTMCDIncreUpdate),which combines distributed computing,storage technology,and incremental update techniques to provide an efficient and effective means for clustering analysis.Firstly,the original dataset is divided into multiple subblocks,and distributed computing resources are utilized to process the sub-blocks in parallel,enhancing efficiency.Then,initial clustering is performed on each sub-block using tensor-based multi-clustering techniques to obtain preliminary results.When new data arrives,incremental update technology is employed to update the core tensor and factor matrix,ensuring that the clustering model can adapt to changes in data.Finally,by combining the updated core tensor and factor matrix with historical computational results,refined clustering results are obtained,achieving real-time adaptation to dynamic data.Through experimental simulation on the Aminer dataset,the BDTMCDIncreUpdate method has demonstrated outstanding performance in terms of accuracy(ACC)and normalized mutual information(NMI)metrics,achieving an accuracy rate of 90%and an NMI score of 0.85,which outperforms existing methods such as TClusInitUpdate and TKLClusUpdate in most scenarios.Therefore,the BDTMCDIncreUpdate method offers an innovative solution to the field of big data analysis,integrating distributed computing,incremental updates,and tensor-based multi-clustering techniques.It not only improves the efficiency and scalability in processing large-scale high-dimensional datasets but also has been validated for its effectiveness and accuracy through experiments.This method shows great potential in real-world applications where dynamic data growth is common,and it is of significant importance for advancing the development of data analysis technology. 展开更多
关键词 TENSOR incremental update distributed clustering processing big data
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A Quality-aware Incremental LMS Algorithm for Distributed Adaptive Estimation
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作者 Wael M.Bazzi Amir Rastegarnia Azam Khalili 《International Journal of Automation and computing》 EI CSCD 2014年第6期676-682,共7页
In this paper, we consider the problem of unknown parameter estimation using a set of nodes that are deployed over an area. The recently proposed distributed adaptive estimation algorithms(also known as adaptive netwo... In this paper, we consider the problem of unknown parameter estimation using a set of nodes that are deployed over an area. The recently proposed distributed adaptive estimation algorithms(also known as adaptive networks) are appealing solutions to the mentioned problem when the statistical information of the underlying process is not available or it varies over time. In this paper, our goal is to develop a new incremental least-mean square(LMS) adaptive network that considers the quality of measurements collected by the nodes. Thus, we use an adaptive combination strategy which assigns each node a step size according to its quality of measurement. The adaptive combination strategy improves the robustness of the proposed algorithm to the spatial variations of signal-to-noise ratio(SNR). The performance of our algorithm is more remarkable in inhomogeneous environments when there are some nodes with low SNRs in the network. The simulation results indicate the efficiency of the proposed algorithm. 展开更多
关键词 Adaptive networks distributed estimation least mean-square (LMS) incremental cooperation quality aware
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An Incremental LOD Method Based on Grid and Its Application in Distributed Terrain Visualization
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作者 MAZhaoting LIChengming PANMao 《Geo-Spatial Information Science》 2005年第2期128-132,共5页
Incremental LOD can be transmitted on the network as a stream, then users on the clients can easily catch the skeleton of terrain without downloading all the data from the server. Detailed information in a local part ... Incremental LOD can be transmitted on the network as a stream, then users on the clients can easily catch the skeleton of terrain without downloading all the data from the server. Detailed information in a local part can be added gradually when users zoom it in without redundant data transmission in this procedure. To do this, an incremental LOD method is put forward according to the regular arrangement of grid. This method applies arbitrary sized grid terrains and is not restricted to square ones with a side measuring 2 k + 1 samples. Maximum height errors are recorded when the LOD is preprocessed and it can be visualized with the geometrical Mipmaps to reduce the screen error. 展开更多
关键词 incremental level of detail grid terrain terrain visualization distributed
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Symbol Error Probability of Incremental Relaying with Distributed/Centralized Relay Selection
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作者 Raed Alhamad Hatem Boujemaa 《China Communications》 SCIE CSCD 2020年第11期141-155,共15页
In this paper,we derive the Symbol Error Probability(SEP)of cooperative systems with incremental relaying and Distributed Relay Selection(DRS).The relays remain idle when the Signal to Noise Ratio(SNR)between the sour... In this paper,we derive the Symbol Error Probability(SEP)of cooperative systems with incremental relaying and Distributed Relay Selection(DRS).The relays remain idle when the Signal to Noise Ratio(SNR)between the source and destination is larger than T.Otherwise,we activate a relay using DRS.Relay nodes transmit only if their SNR is larger than thresholdβ.If the SNRs of more than two relays is larger thanβ,there is a collision and the destination uses only the received signal from the source.If all relays have SNR less thanβ,no relay is chosen.Thresholdβis optimized to yield the lowest SEP at the destination.Our results are compared to centralized relay selection using opportunistic Amplify and Forward(OAF),Partial and Reactive Relay Selection(PRS and RRS).We compare our results to computer simulations for Rayleigh fading channels. 展开更多
关键词 incremental relaying distributed relay selection centralized relay selection rayleigh fading channels
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iHDFS: A Distributed File System Supporting Incremental Computing
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作者 Zhenhua Wang Qingsong Ding +2 位作者 Fuxiang Gao Derong Shen Ge Yu 《国际计算机前沿大会会议论文集》 2015年第1期44-45,共2页
Big data are always processed repeatedly with small changes, which is a major form of big data processing. The feature of incremental change of big data shows that incremental computing mode can improve the performanc... Big data are always processed repeatedly with small changes, which is a major form of big data processing. The feature of incremental change of big data shows that incremental computing mode can improve the performance greatly. HDFS is a distributed file system on Hadoop which is the most popular platform for big data analytics. And HDFS adopts fixed-size chunking policy, which is inefficient facing incremental computing. Therefore, in this paper, we proposed iHDFS (incremental HDFS), a distributed file system, which can provide basic guarantee for big data parallel processing. The iHDFS is implemented as an extension to HDFS. In iHDFS, Rabin fingerprint algorithm is applied to achieve content defined chunking. This policy make data chunking has much higher stability, and the intermediate processing results can be reused efficiently, so the performance of incremental data processing can be improved significantly. The effectiveness and efficiency of iHDFS have been demonstrated by the experimental results. 展开更多
关键词 incremental COMPUTING distributed FILE system BIG data HDFS
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Thickness distribution of multi-stage incremental forming with different forming stages and angle intervals 被引量:1
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作者 李军超 杨芬芬 周志强 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第3期842-848,共7页
Although multi-stage incremental sheet forming has always been adopted instead of single-stage forming to form parts with a steep wall angle or to achieve a high forming performance, it is largely dependent on empiric... Although multi-stage incremental sheet forming has always been adopted instead of single-stage forming to form parts with a steep wall angle or to achieve a high forming performance, it is largely dependent on empirical designs. In order to research multi-stage forming further, the effect of forming stages(n) and angle interval between the two adjacent stages(Δα) on thickness distribution was investigated. Firstly, a finite element method(FEM) model of multi-stage incremental forming was established and experimentally verified. Then, based on the proposed simulation model, different strategies were adopted to form a frustum of cone with wall angle of 30° to research the thickness distribution of multi-pass forming. It is proved that the minimum thickness increases largely and the variance of sheet thickness decreases significantly as the value of n grows. Further, with the increase of Δα, the minimum thickness increases initially and then decreases, and the optimal thickness distribution is achieved with Δα of 10°.Additionally, a formula is deduced to estimate the sheet thickness after multi-stage forming and proved to be effective. And the simulation results fit well with the experimental results. 展开更多
关键词 incremental forming multi-stage forming angle interval thickness distribution
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Investigation of spatiotemporal distribution and formation mechanisms of ozone pollution in eastern Chinese cities applying convolutional neural network 被引量:1
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作者 Qiaoli Wang Dongping Sheng +7 位作者 Chengzhi Wu Xiaojie Ou Shengdong Yao Jingkai Zhao Feili Li Wei Li Jianmeng Chen 《Journal of Environmental Sciences》 2025年第2期126-138,共13页
Severe ground-level ozone(O_(3))pollution over major Chinese cities has become one of the most challenging problems,which have deleterious effects on human health and the sustainability of society.This study explored ... Severe ground-level ozone(O_(3))pollution over major Chinese cities has become one of the most challenging problems,which have deleterious effects on human health and the sustainability of society.This study explored the spatiotemporal distribution characteristics of ground-level O_(3) and its precursors based on conventional pollutant and meteorological monitoring data in Zhejiang Province from 2016 to 2021.Then,a high-performance convolutional neural network(CNN)model was established by expanding the moment and the concentration variations to general factors.Finally,the response mechanism of O_(3) to the variation with crucial influencing factors is explored by controlling variables and interpolating target variables.The results indicated that the annual average MDA8-90th concentrations in Zhejiang Province are higher in the northern and lower in the southern.When the wind direction(WD)ranges from east to southwest and the wind speed(WS)ranges between 2 and 3 m/sec,higher O_(3) concentration prone to occur.At different temperatures(T),the O_(3) concentration showed a trend of first increasing and subsequently decreasing with increasing NO_(2) concentration,peaks at the NO_(2) concentration around 0.02mg/m^(3).The sensitivity of NO_(2) to O_(3) formation is not easily affected by temperature,barometric pressure and dew point temperature.Additionally,there is a minimum IRNO_(2) at each temperature when the NO_(2) concentration is 0.03 mg/m^(3),and this minimum IRNO_(2) decreases with increasing temperature.The study explores the response mechanism of O_(3) with the change of driving variables,which can provide a scientific foundation and methodological support for the targeted management of O_(3) pollution. 展开更多
关键词 OZONE Spatiotemporal distribution Convolutional neural network Ozone formation rules incremental reactivity
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Hybrid partition-and network-level scheduling design for distributed integrated modular avionics systems 被引量:9
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作者 Xuan ZHOU Huagang XIONG Feng HE 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2020年第1期308-323,共16页
Distributed Integrated Modular Avionics(DIMA)develops from Integrated Modular Avionics(IMA)and realizes distributed integration of multiple sub-function areas.Timetriggered network provides effective support for time ... Distributed Integrated Modular Avionics(DIMA)develops from Integrated Modular Avionics(IMA)and realizes distributed integration of multiple sub-function areas.Timetriggered network provides effective support for time synchronization and information coordination in DIMA systems.However,inconsistency between processing resources and communication network destroys the time determinism benefiting from partitions and time-triggered mechanism.To ensure such time determinism and achieve guaranteed real-time performance,system design should collectively provide a global communication scheme for messages in network domain and a corresponding execution scheme for partitions in processing domain.This paper firstly establishes a general DIMA model which coordinates partitioned processing and time-triggered communication,and then proposes a hybrid scheduling algorithm using Mixed Integer Programming to produce feasible system schemes.Furthermore,incrementally integrating new functions causes upgrades or reconfigurations of DIMA systems and will generate integration cost.To control such cost,this paper further develops an optimization algorithm based on Maximum Satisfiability Problem and guarantees that the scheduling design for upgraded DIMA systems inherit their original schemes as much as possible.Finally,two typical cases,including a simple fully connected DIMA system case and an industrial DIMA system case,are constructed to illustrate our DIMA model and validate the effectiveness of our hybrid scheduling algorithms. 展开更多
关键词 distributed INTEGRATED modular AVIONICS END-TO-END delay incremental integration cost Maximum SATISFIABILITY problem Mixed INTEGER programming Scheduling algorithms
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ON THE INCREMENTS DISTRIBUTION OF STOCK PRICES
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作者 Korolev V Yu 1 Zhao Xuanmin 2 Bening V E 11 Faculty of Computational Mathematics and Cybenetics,Moscow State Univ., Moscow 119899. 2 Dept. of Appl. Math., Northwestern Polytechnical Univ., Xi’an 710072. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2001年第3期315-322,共8页
In this paper,the models of increment distributions of stock price are constructed with two approaches. The first approach is based on limit theorems of random summation. The second approach is based on the statistica... In this paper,the models of increment distributions of stock price are constructed with two approaches. The first approach is based on limit theorems of random summation. The second approach is based on the statistical analysis of the increment distribution of the logarithms of stock prices. 展开更多
关键词 increment distributions of stock price Cox process mixing distribution.
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Incremental Static Analysis of 2D Flow by Inter-Colliding Point-Particles and Use of Incompressible Rhombic Element 被引量:1
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作者 Panagis G. Papadopoulos Christopher G. Koutitas Panos P. Lazaridis 《Open Journal of Civil Engineering》 2016年第3期397-409,共13页
A simple method is proposed, for incremental static analysis of a set of inter-colliding particles, simulating 2D flow. Within each step of proposed algorithm, the particles perform small displacements, proportional t... A simple method is proposed, for incremental static analysis of a set of inter-colliding particles, simulating 2D flow. Within each step of proposed algorithm, the particles perform small displacements, proportional to the out-of-balance forces, acting on them. Numerical experiments show that if the liquid is confined within boundaries of a set of inter-communicating vessels, then the proposed method converges to a final equilibrium state. This incremental static analysis approximates dynamic behavior with strong damping and can provide information, as a first approximation to 2D movement of a liquid. In the initial arrangement of particles, a rhombic element is proposed, which assures satisfactory incompressibility of the fluid. Based on the proposed algorithm, a simple and short computer program (a “pocket” program) has been developed, with only about 120 Fortran instructions. This program is first applied to an amount of liquid, contained in a single vessel. A coarse and refined discretization is tried. In final equilibrium state of liquid, the distribution on hydro-static pressure on vessel boundaries, obtained by proposed computational model, is found in satisfactory approximation with corresponding theoretical data. Then, an opening is formed, at the bottom of a vertical boundary of initial vessel, and the liquid is allowed to flow gradually to an adjacent vessel. Almost whole amount of liquid is transferred, from first to second vessel, except of few drops-particles, which remain, in equilibrium, at the bottom of initial vessel. In the final equilibrium state of liquid, in the second vessel, the free surface level of the liquid confirms that the proposed rhombing element assures a satisfactory incompressibility of the fluid. 展开更多
关键词 2D Flow Simulation Inter-Colliding Point-Particles incremental Static Analysis Incompressible Rhombic Element Hydro-Static Pressure distribution Flow from a Vessel to Another One “Pocket” Special Purpose Computer Program
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Distributed Adaptive Learning Framework for Wide Area Monitoring of Power Systems Integrated with Distributed Generations
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作者 Kang Li Yuanjun Guo +2 位作者 David Laverty Haibo He Minrui Fei 《Energy and Power Engineering》 2013年第4期962-969,共8页
This paper presents a preliminary study of developing a novel distributed adaptive real-time learning framework for wide area monitoring of power systems integrated with distributed generations using synchrophasor tec... This paper presents a preliminary study of developing a novel distributed adaptive real-time learning framework for wide area monitoring of power systems integrated with distributed generations using synchrophasor technology. The framework comprises distributed agents (synchrophasors) for autonomous local condition monitoring and fault detection, and a central unit for generating global view for situation awareness and decision making. Key technologies that can be integrated into this hierarchical distributed learning scheme are discussed to enable real-time information extraction and knowledge discovery for decision making, without explicitly accumulating and storing all raw data by the central unit. Based on this, the configuration of a wide area monitoring system of power systems using synchrophasor technology, and the functionalities for locally installed open-phasor-measurement-units (OpenPMUs) and a central unit are presented. Initial results on anti-islanding protection using the proposed approach are given to illustrate the effectiveness. 展开更多
关键词 SMART GRID Anti-islanding Protection distributed AGENTS incremental Learning Monitoring and Control
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Distribution of Land Increment Income from Marketing Rural Collective Land for Development Purposes : A Case Study of Changyuan City
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作者 Chenguang YUAN Lingchao WANG +2 位作者 Yanhua SONG Ziwei WANG Yan TIAN 《Asian Agricultural Research》 2021年第10期31-36,共6页
In order to protect the property rights and interests of farmers,promote the revitalization and development of rural areas,and provide a reference basis for the reform of marketing rural collective land for developmen... In order to protect the property rights and interests of farmers,promote the revitalization and development of rural areas,and provide a reference basis for the reform of marketing rural collective land for development purposes,this study explores the reasonable distribution proportion of land increment income from marketing rural collective land for development purposes through analytic hierarchy process and Delphi expert scoring method.The results show that there is a positive correlation between land increment income and land grade,that is,the higher the land grade,the higher the increment income,the larger the proportion of increment income to the transaction price.According to the calculation,when marketing rural collective land for development purposes,the reasonable distribution proportion of the land increment income of the government and the village collective is 28.6%and 71.4%,respectively,and the land increment income actually obtained by farmers has been greatly improved compared with the current situation.In practice,this distribution model has universal applicability and long-term mechanism.The reform of marketing also needs to improve the standard of marketing,explore diversified channels to protect interests,and strengthen the construction of rural collective management system.In short,the distribution of land increment income from marketing rural collective land for development purposes should proceed from the perspective of land property rights and the factors affecting the price of collective land for development purposes,in order to build a reasonable income distribution model. 展开更多
关键词 Rural collective land for development purposes Land increment income Rational distribution Analytic hierarchy process
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Incremental Pressing Technique in Explosive Charge
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作者 TiAN Li-yan XU Geng-guang 《含能材料》 EI CAS CSCD 2001年第4期165-167,共3页
A pressing technique has become available that might be useful for compressing granular explosives. If the height diameter ratio of the charge is unfavorable,the high quality charge can not be obtained with the common... A pressing technique has become available that might be useful for compressing granular explosives. If the height diameter ratio of the charge is unfavorable,the high quality charge can not be obtained with the common single action pressing. This paper presents incremental pressing technique, which can obtain the charge with higher overall density and more uniform density. 展开更多
关键词 爆炸装填物 增加压力技术 松装密度
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一种基于交叉验证的多视角无人机影像立体像对选择方法
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作者 杨涛 李佳田 +1 位作者 阿晓荟 李思旭 《测绘科学》 北大核心 2025年第6期123-133,共11页
针对无人机多视角三维立体建模过程中,无序影像集(或其子集)具有随机性,进而影响建模稳健性的问题,该文提出一种基于交叉验证的影像选择方法,通过随机抽样和方差分析选择影像。首先,为确保最大程度地利用影像集中的信息,同时避免过度依... 针对无人机多视角三维立体建模过程中,无序影像集(或其子集)具有随机性,进而影响建模稳健性的问题,该文提出一种基于交叉验证的影像选择方法,通过随机抽样和方差分析选择影像。首先,为确保最大程度地利用影像集中的信息,同时避免过度依赖特定的影像,对原始影像集进行随机采样分组。其次,利用影像几何特征,并联合影像特征匹配数量及特征分布情况来选择每组内最佳候选初始影像对。然后,再根据初始影像对选择场景重建所需后续影像。最后,对所有分组进行模型评定以及模型选择后利用全局优化方法对重建结果优化。对比实验结果表明,在3组小规模数据集上重投影误差分别为0.436、0.849、0.483像素,较Colmap方法分别降低45.6%、33.5%和26.2%。在大规模数据集上的重投影误差为0.338像素,精度优于对比方法,且本文方法对于实验场景具有更好的稳健性。 展开更多
关键词 三维重建 影像选择 特征分布 交叉验证 增量重建
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张量多聚类分布式增量更新在企业管理中的应用
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作者 王定军 朱良海 +2 位作者 张浩 张宏俊 潘高军 《办公自动化》 2025年第6期97-100,共4页
文章针对企业管理中的物联网印章应用问题,基于张量多聚类分布式增量更新的理论基础,提出一种分布式增量更新的企业管理模型。通过对物联网印章在企业管理中的应用案例分析,验证该模型的实际效果。分析结果表明,该模型可有效提高企业管... 文章针对企业管理中的物联网印章应用问题,基于张量多聚类分布式增量更新的理论基础,提出一种分布式增量更新的企业管理模型。通过对物联网印章在企业管理中的应用案例分析,验证该模型的实际效果。分析结果表明,该模型可有效提高企业管理效率,降低成本,为企业决策提供更加科学的依据。 展开更多
关键词 张量多聚类 分布式增量更新 企业管理 物联网印章
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复杂形状零件单点渐进液压成形厚度分布研究
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作者 尚苗 李言 +1 位作者 山顺坤 杨明顺 《中国机械工程》 北大核心 2025年第6期1338-1344,共7页
为了分析和提高复杂形状零件的单点渐进成形性能,提出了一种由单点渐进成形和液压成形混合而成的新工艺,用于制造具有尖顶结构的多特征零件。设计了目标制件的成形过程,建立了厚度理论预测模型,分析了不同液压参数在不同成形阶段对目标... 为了分析和提高复杂形状零件的单点渐进成形性能,提出了一种由单点渐进成形和液压成形混合而成的新工艺,用于制造具有尖顶结构的多特征零件。设计了目标制件的成形过程,建立了厚度理论预测模型,分析了不同液压参数在不同成形阶段对目标零件厚度分布的影响。实验结果表明,采用新工艺和合适的液压压力可以成形复杂形零件;与无液压辅助的渐进成形相比,有液压辅助时实验轮廓与理论轮廓的几何误差能够从11.44%降低到5.18%;厚度分布规律与辅助压力、成形高度、成形形状等有关,所建立理论模型能够预测复杂形零件的厚度分布。 展开更多
关键词 复杂形状 单点渐进成形 液压成形 厚度分布
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增量配电网改革背景下居民用电诉求研究——MRDE模型初探
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作者 陈浩然 孙睿 +3 位作者 刘宇 高春辉 杨朋威 殷宗萍 《管理评论》 北大核心 2025年第4期17-32,共16页
传统观点认为居民对于任何形式的电价上涨均持反对态度。本文通过细化研究居民具体的用电诉求及其相互间的作用关系,为解决我国当前增量配电网改革主要困难之一的居民电价交叉补贴问题提供可靠参考,采用问卷法调研了376个家庭的用电诉求... 传统观点认为居民对于任何形式的电价上涨均持反对态度。本文通过细化研究居民具体的用电诉求及其相互间的作用关系,为解决我国当前增量配电网改革主要困难之一的居民电价交叉补贴问题提供可靠参考,采用问卷法调研了376个家庭的用电诉求,采用结构方程分析法构建了反映居民用电诉求的MRDE模型。本文发现,居民可以接受基于相关指标优化后的电价上涨,其中服务水平和电压合格率因素对电价上涨预期存在直接的正向影响,电能质量和供电可靠性因素对电价上涨预期存在间接的正向影响。 展开更多
关键词 增量配电网改革 电价交叉补贴 居民用电诉求 MRDE模型
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面向配电网扩展规划的可靠性快速评估方法 被引量:2
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作者 王智爽 庞超 +3 位作者 马世乾 靳开元 梁蕊宏 葛路琨 《智慧电力》 北大核心 2025年第7期108-114,共7页
为应对用电需求快速增长背景下配电网扩展规划日益凸显的重要性,提出了一种基于可靠性增量的快速评估方法。首先,该方法将扩展后配电网的可靠性指标拆分为现状配电网的可靠性指标与扩展部分的可靠性增量,通过复用现有可靠性指标并仅计... 为应对用电需求快速增长背景下配电网扩展规划日益凸显的重要性,提出了一种基于可靠性增量的快速评估方法。首先,该方法将扩展后配电网的可靠性指标拆分为现状配电网的可靠性指标与扩展部分的可靠性增量,通过复用现有可靠性指标并仅计算增量部分,显著降低了计算量;其次,构建了一种增量相关故障状态识别方法,筛选与可靠性增量相关的故障状态并剔除无关状态,进一步提升评估效率;最后,基于改进的RBTS Bus6 Feeder4算例验证表明,该方法可显著提高配电网扩展规划的可靠性评估效率。 展开更多
关键词 配电网扩展规划 可靠性评估 可靠性增量 可靠性指标拆分 计算效率优化
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掺合料水泥浆体碳化规律的可视化和定量表征
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作者 洪舒贤 彭毅 +3 位作者 姜荣嵘 范圣新 王煦 董必钦 《西安建筑科技大学学报(自然科学版)》 北大核心 2025年第4期581-591,共11页
掺入粉煤灰、矿渣后,水泥浆体的碳化规律变得复杂.一方面,加入掺合料会影响水泥浆体的孔隙结构.另一方面,掺合料部分替代水泥会导致水泥浆体内氢氧化钙的含量降低.为了解析这一复杂的过程,采用X射线成像技术追踪监测碳化龄期内样品的密... 掺入粉煤灰、矿渣后,水泥浆体的碳化规律变得复杂.一方面,加入掺合料会影响水泥浆体的孔隙结构.另一方面,掺合料部分替代水泥会导致水泥浆体内氢氧化钙的含量降低.为了解析这一复杂的过程,采用X射线成像技术追踪监测碳化龄期内样品的密度变化情况,以此研究矿物掺合料-水泥浆体在多因素耦合作用下的碳化演变规律,并结合热重测试(TGA)和压汞测试(MIP)的结果进行分析.结果表明,X射线成像技术可以可视化且定量表征多因素耦合作用下浆体的抗碳化性能变化规律,掺合料水泥浆体的抗碳化性能高于水泥净浆(Ref组),而随着替代率的升高,粉煤灰水泥浆体(FA组)的抗碳化性能下降,矿渣水泥浆体(SLAG组)的抗碳化性能先上升后下降,二者的最佳替代率分别为10%和30%.掺合料-水泥浆体的抗碳化性能受到氢氧化钙含量变化和孔隙结构优化程度二者竞争关系的影响,仅单一方面的分析无法得到正确的碳化规律. 展开更多
关键词 掺合料 密度增量曲线 孔径分布 定量表征 抗碳化性能
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目标检测技术在开放环境中的挑战与进展 被引量:1
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作者 操晓春 赵思成 +2 位作者 武阿明 梁思源 王立元 《中国图象图形学报》 北大核心 2025年第6期1616-1637,共22页
目标检测是计算机视觉领域的核心任务,其通过深度神经网络技术识别图像中的视觉对象并预测其位置和类别。在闭集环境下,目标检测器已显著展现出实用价值;然而,在开放环境中,这些系统面临诸多挑战,包括不断变化的数据分布、新类别的出现... 目标检测是计算机视觉领域的核心任务,其通过深度神经网络技术识别图像中的视觉对象并预测其位置和类别。在闭集环境下,目标检测器已显著展现出实用价值;然而,在开放环境中,这些系统面临诸多挑战,包括不断变化的数据分布、新类别的出现以及噪声干扰,均可能影响决策准确性。相较于闭集环境下的综述性研究,开放环境中的目标检测及其特有挑战的应对策略仍显不足。本文深入分析开放环境下目标检测面临的主要挑战,包括域外和类别外数据的处理,以及如何通过鲁棒和增量学习适应环境动态。首次全面分析现有检测方法如何应对这些挑战,总结它们在适应新场景、提高决策鲁棒性以及支持持续学习方面的方法。进一步地,探讨改进目标检测系统的可能方向,包括开发能够处理更广泛数据集的新方法,整合领域知识增强决策的上下文依赖性,设计动态适应的攻防机制和新类别的学习算法。通过这项工作,希望为开放环境中的目标检测技术提供一种全新的、系统化的视角,以促进未来更加稳健的解决方案开发,并推动该技术在实际应用中的进一步发展。 展开更多
关键词 目标检测 开放环境 深度学习 鲁棒性 类别外检测 增量学习 数据分布变化
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