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Algorithmic approach to discrete fracture network flow modeling in consideration of realistic connections in large-scale fracture networks
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作者 Qihua Zhang Shan Dong +2 位作者 Yaoqi Liu Junjie Huang Feng Xiong 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第9期3798-3811,共14页
Analyzing rock mass seepage using the discrete fracture network(DFN)flow model poses challenges when dealing with complex fracture networks.This paper presents a novel DFN flow model that incorporates the actual conne... Analyzing rock mass seepage using the discrete fracture network(DFN)flow model poses challenges when dealing with complex fracture networks.This paper presents a novel DFN flow model that incorporates the actual connections of large-scale fractures.Notably,this model efficiently manages over 20,000 fractures without necessitating adjustments to the DFN geometry.All geometric analyses,such as identifying connected fractures,dividing the two-dimensional domain into closed loops,triangulating arbitrary loops,and refining triangular elements,are fully automated.The analysis processes are comprehensively introduced,and core algorithms,along with their pseudo-codes,are outlined and explained to assist readers in their programming endeavors.The accuracy of geometric analyses is validated through topological graphs representing the connection relationships between fractures.In practical application,the proposed model is employed to assess the water-sealing effectiveness of an underground storage cavern project.The analysis results indicate that the existing design scheme can effectively prevent the stored oil from leaking in the presence of both dense and sparse fractures.Furthermore,following extensive modification and optimization,the scale and precision of model computation suggest that the proposed model and developed codes can meet the requirements of engineering applications. 展开更多
关键词 Discrete fracture network(DFN)flow model Geometric algorithm Fracture flow Water-sealing effect
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Multi-layer Tectonic Model for Intraplate Deformation and Plastic-Flow Network in the Asian Continental Lithosphere 被引量:4
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作者 Wang Shengzu Institute of Geology, State Seismological Bureau, Beijing Liu Linqun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1993年第3期247-271,共25页
In a large area of the east—central Asian continent there is a unified seismic network system composed of two families of large—seismic belts that intersect conjugately. Such a seismic network in the middle—upper c... In a large area of the east—central Asian continent there is a unified seismic network system composed of two families of large—seismic belts that intersect conjugately. Such a seismic network in the middle—upper crust is actually a response to the plastic flow network in the lower lithosphere including the lower crust and lithospheric mantle. The existence of the unified plastic flow system confirms that the driving force for intraplate tectonic deformation results mainly from the compression of the India plate, while the long-range transmission of the force is carried out chiefly by means of plastic flow. The plastic flow network has a control over the intraplate tectonic deformation. 展开更多
关键词 Continental lithosphere tectonic deformation multi-layer tectonic model large-scale seismic belt seismic network plastic flow network
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Modeling of the Coupling of the Lightning Shock Wave Flow Circuit in the High Voltage Electrical Network
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作者 Mwanamputu Mbwanzo Timothée Nsongo +2 位作者 Pasi Bengi Masata Andre Flory Lidinga Mobonda Mathurin Gogom 《Energy and Power Engineering》 CAS 2022年第8期404-419,共16页
This article focuses on the aggression of lightning overload on the equipment of the electrical network of sites where storm activity is very dense;and the electrocution of people located in the direct environment of ... This article focuses on the aggression of lightning overload on the equipment of the electrical network of sites where storm activity is very dense;and the electrocution of people located in the direct environment of the high-voltage substation during the flow of lightning current to the ground through the ground socket. The modeling of the flow circuit of the shock wave consisting of guard wire, lightning arrester and ground socket couple to the transformer of the high voltage substations, thanks to the approach of a servo block, led to the synthesis of a PID regulator (corrector) whose action is to reject the effects of the overvoltage on the network equipment and to significantly reduce or even cancel the effects of the step or touch voltage due to the distribution of the potential around the ground socket;and thus improve the quality of service of the high-voltage transmission and distribution electricity network, especially in stormy times. 展开更多
关键词 modeling COUPLING flow Circuit Shock Wave LIGHTNING Electrical network High Voltage
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Parameter estimation in channel network flow simulation 被引量:1
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作者 Han Longxi 《Water Science and Engineering》 EI CAS 2008年第1期10-17,共8页
Simulations of water flow in channel networks require estimated values of roughness for all the individual channel segments that make up a network. When the number of individual channel segments is large, the paramete... Simulations of water flow in channel networks require estimated values of roughness for all the individual channel segments that make up a network. When the number of individual channel segments is large, the parameter calibration workload is substantial and a high level of uncertainty in estimated roughness cannot be avoided. In this study, all the individual channel segments are graded according to the factors determining the value of roughness. It is assumed that channel segments with the same grade have the same value of roughness. Based on observed hydrological data, an optimal model for roughness estimation is built. The procedure of solving the optimal problem using the optimal model is described. In a test of its efficacy, this estimation method was applied successfully in the simulation of tidal water flow in a large complicated channel network in the lower reach of the Yangtze River in China. 展开更多
关键词 hydrodynamic model channel network flow simulation ROUGHNESS
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A New Algorithm to Automatically Extract the Drainage Networks and Catchments Based on Triangulation Irregular Network Digital Elevation Model 被引量:3
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作者 屈国栋 苏丹阳 楼章华 《Journal of Shanghai Jiaotong university(Science)》 EI 2014年第3期367-377,共11页
A new algorithm to automatically extract drainage networks and catchments based on triangulation irregular networks(TINs) digital elevation model(DEM) was developed. The flow direction in this approach is determined b... A new algorithm to automatically extract drainage networks and catchments based on triangulation irregular networks(TINs) digital elevation model(DEM) was developed. The flow direction in this approach is determined by computing the spatial gradient of triangle and triangle edges. Outflow edge was defined by comparing the contribution area that is separated by the steepest descent of the triangle. Local channels were then tracked to build drainage networks. Both triangle edges and facets were considered to construct flow path. The algorithm has been tested in the site for Hawaiian Island of Kaho'olawe, and the results were compared with those calculated by ARCGIS as well as terrain map. The reported algorithm has been proved to be a reliable approach with high efficiency to generate well-connected and coherent drainage networks. 展开更多
关键词 drainage networks catchment extraction flow direction triangulation irregular network(TIN) digital elevation model(DEM) hydrological model
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Incident Detection Method of Expressway Based on Traffic Flow Simulation Model 被引量:1
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作者 Shu-Bin Li Tao Sun +1 位作者 Dan-Ni Cao Lin Zhang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2019年第4期468-474,共7页
The expressway traffc incidents have the characteristics of high harmful, strong destructive and refractory.Incident detection can guarantee smooth operation of the expressway, reduce traffc congestion and avoid secon... The expressway traffc incidents have the characteristics of high harmful, strong destructive and refractory.Incident detection can guarantee smooth operation of the expressway, reduce traffc congestion and avoid secondary accident by informing the accident, detection and treatment timely. In this paper, an incident detection method is proposed using the toll station data that takes into account the traffc ratio at the entrances and crossway in the network. The expressway traffc simulation model is improved and a simulation algorithm is established to describe the movement of the vehicles. A numerical example is experimented on the expressway network of Shandong province. The proposed method can effectively detect the expressway incidents, and dynamically estimate the traffc network states so as to provide advice for the highway management department. 展开更多
关键词 EXPRESSWAY traffc flow simulation model incident detection network state estimation
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Dynamic Characteristics Analysis on MHTGR Plant’s Secondary Side Fluid Flow Network 被引量:1
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作者 Maoxuan Song Zhe Dong 《Journal of Power and Energy Engineering》 2016年第7期15-22,共8页
Multipe NSSS (Nuclear Steam Supply System) modules use the common feeding-water system to drive the common turbine power generation set. The SSFFN (secondary side fluid flow network) of MHTGR plant has features i.e. s... Multipe NSSS (Nuclear Steam Supply System) modules use the common feeding-water system to drive the common turbine power generation set. The SSFFN (secondary side fluid flow network) of MHTGR plant has features i.e. strong-coupling and nonlinearity. A wide range of power switching operation will cause unsteady flow, which may destroy the working elements and will be a threat for normal operation. To overcome those problems, a differential-algebraic model and PI controllers are designed for the SSFFN. In MATLAB\SIMULINK environment, a simulation platform is established and used to make a simulation of SSFFN of a MHTGR plant with two NSSS modules, which uses feedwater valves to control the mass flow rate in each module instead of feedwater pump. Results reflect good robustness of controllers. 展开更多
关键词 MHTGR Plant Secondary Side Fluid flow network a Differential-Algebraic model PI Controllers
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Modeling Simulation Technology Research for Distribution Network Planning
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作者 Huanghuang Liu Dan Liu Qianjin Liu 《Energy and Power Engineering》 2013年第4期980-985,共6页
This paper proposes to use the power system simulation software CYME to plan, model and simulate for an actual distribution network for improving the reliability and efficiency, enhancing the efficiency and capacity, ... This paper proposes to use the power system simulation software CYME to plan, model and simulate for an actual distribution network for improving the reliability and efficiency, enhancing the efficiency and capacity, simulating the abnormal condition of distribution network, and presenting operation program of safe, reliable and having simulation record statements. The modeling simulation results show that the software module has lots of advantages including high accuracy, ideal reliability, powerful practicality in simulation and analysis of distribution network, it only need to create once model, the model can sufficiently satisfy multifarious types of simulation analysis required for the distribution network planning. 展开更多
关键词 DISTRIBUTION network PLANNING modeling Simulation LOAD flow CALCULATION REACTIVE Power Optimization LOAD Balancing
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LLFlowGAN:以生成对抗方式约束可逆流的低照度图像增强 被引量:5
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作者 黄颖 彭慧 +2 位作者 李昌盛 高胜美 陈奉 《中国图象图形学报》 CSCD 北大核心 2024年第1期65-79,共15页
目的现有低照度图像增强方法大多依赖于像素级重建,旨在学习低照度输入和正常曝光图像之间的确定性映射,没有对复杂的光照分布进行建模,从而导致了不适当的亮度及噪声。大多图像生成方法仅使用一种(显式或隐式)生成模型,在灵活性和效率... 目的现有低照度图像增强方法大多依赖于像素级重建,旨在学习低照度输入和正常曝光图像之间的确定性映射,没有对复杂的光照分布进行建模,从而导致了不适当的亮度及噪声。大多图像生成方法仅使用一种(显式或隐式)生成模型,在灵活性和效率方面有所限制。为此,改进了一种混合显式—隐式的生成模型,该模型允许同时进行对抗训练和最大似然训练。方法首先设计了一个残差注意力条件编码器对低照度输入进行处理,提取丰富的特征以减少生成图像的色差;然后,将编码器提取到的特征作为可逆流生成模型的条件先验,学习将正常曝光图像的分布映射为高斯分布的双向映射,以此来模拟正常曝光图像的条件分布,使模型能够对多个正常曝光结果进行采样,生成多样化的样本;最后,利用隐式生成对抗网络(generative adversarial network,GAN)为模型提供约束,改善图像的细节信息。特别地,两个映射方向都受到损失函数的约束,因此本文设计的模型具有较强的抗模式崩溃能力。结果实验在2个数据集上进行训练与测试,在低照度(low-light dataset,LOL)数据集与其他算法对比,本文算法在峰值信噪比(peak signal-to-noise ratio,PSNR)上均有最优表现、图像感知相似度(learned perceptual image patch similarity,LPIPS)、在结构相似性(structural similarity index measure,SSIM)上取得次优表现0.01,在无参考自然图像质量指标(natural image quality evaluator,NIQE)上取得较优结果。具体地,相较于18种现有显著性模型中的最优值,本文算法PSNR提高0.84 dB,LPIPS降低0.02,SSIM降低0.01,NIQE值降低1.05。在MIT-Adobe FiveK(Massachu-setts Institute of Technology Adobe FiveK)数据集中,与5种显著性模型进行对比,相较于其中的最优值,本文算法PSNR提高0.58 dB,SSIM值取得并列第一。结论本文提出的流生成对抗模型,综合了显式和隐式生成模型的优点,更好地调整了低照度图像的光照,抑制了噪声和伪影,提高了生成图像的视觉感知质量。 展开更多
关键词 低照度图像增强 流模型 生成对抗网络(GAN) 双向映射 复杂光照分布
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基于MapReduce的OpenFlow网络属性验证技术 被引量:3
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作者 刘艺 雷程 +1 位作者 张红旗 杨英杰 《计算机研究与发展》 EI CSCD 北大核心 2016年第11期2500-2511,共12页
针对OpenFlow网络中由程序自动改变数据平面状态方式引起的流表配置错误问题,提出1种基于MapReduce的OpenFlow网络属性验证技术.首先,利用OpenFlow网络控制转发分离的特点,设计支持实时与非实时2种验证方式的技术架构.其次,提出基于MapR... 针对OpenFlow网络中由程序自动改变数据平面状态方式引起的流表配置错误问题,提出1种基于MapReduce的OpenFlow网络属性验证技术.首先,利用OpenFlow网络控制转发分离的特点,设计支持实时与非实时2种验证方式的技术架构.其次,提出基于MapReduce模型的非实时验证算法,在Map阶段划分规则等价类,在Reduce阶段构建基于交换机端口谓词的网络转发图并分析可达性,以实现对网络属性的并行验证.与此同时,利用原子谓词消除谓词集合冗余项和规则匹配域转换的方法,提高可达性分析效率.此外,在非实时验证算法的基础上,结合网络更新事件提出实时验证算法,实现网络状态改变时的增量式网络属性验证.最后,理论分析和仿真实验验证了该技术的运行效率和存储开销,并分析了其对TCP连接建立时间的影响. 展开更多
关键词 流表配置 网络可达性分析 网络属性验证 MAPREDUCE模型 Openflow网络
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基于多维特征融合与残差增强的交通流量预测
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作者 张振琳 郭慧洁 +4 位作者 窦天凤 亓开元 吴栋 曲志坚 任崇广 《计算机应用研究》 北大核心 2026年第1期161-169,共9页
交通流量预测在智能交通系统中占据核心地位。针对当前交通流量预测方法在特征利用和时空依赖建模方面的不足,提出了一种新的基于多维特征融合与残差增强的交通流量预测模型MFRGCRN(multi-dimensional feature fusion and residual-enha... 交通流量预测在智能交通系统中占据核心地位。针对当前交通流量预测方法在特征利用和时空依赖建模方面的不足,提出了一种新的基于多维特征融合与残差增强的交通流量预测模型MFRGCRN(multi-dimensional feature fusion and residual-enhanced graph convolutional recurrent network)。该模型通过结合自编码器、深度可分离卷积及时间卷积全方位挖掘时空相关性,使用门控循环单元与多尺度卷积注意力结合学习数据的关联关系,同时利用多尺度残差增强机制实现对复杂模式的逐步建模。在四个真实数据集上的实验结果表明,所提出的模型在预测性能上优于对比的基线模型,尤其在PEMS08数据集的12步预测任务中,MAE、RMSE和MAPE分别降低约7.7%、2.9%和4.5%,展现出优异的长期预测能力。模型在准确性、稳定性和鲁棒性方面均表现出较强优势,为智能交通系统中的复杂交通流建模提供了有效解决方案。 展开更多
关键词 交通流量预测 动态图卷积网络 特征融合 残差建模 注意力机制
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Pore-scale study of the pressure-sensitive effect of sandstone and its influence on multiphase flows 被引量:4
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作者 Jun-Jian Li Yang Liu +2 位作者 Ya-Jun Gao Bao-Yang Cheng Han-Qiao Jiang 《Petroleum Science》 SCIE CAS CSCD 2019年第2期382-395,共14页
The pressure-sensitive effect on the pore structure of sandstone was investigated using X-ray computed micro-tomography and QEMSCAN quantitative mineral analysis. In a physical simulation study, we extracted the pore ... The pressure-sensitive effect on the pore structure of sandstone was investigated using X-ray computed micro-tomography and QEMSCAN quantitative mineral analysis. In a physical simulation study, we extracted the pore network model from digital cores at different confining pressures and evaluated the effect of pressure sensitivity on the multiphase displacement process. In both the pore network model and QEMSCAN scanning, the pore structure was observed to be damaged under a high confining pressure. Due to their different scales, the pores and throats exhibited inhomogeneous changes; further, the throats exhibited a significant variation compared to that exhibited by the pores. Meanwhile, the heterogeneity of the pore structure under the two aforementioned activities was aggravated by the elastic-plastic deformation of the pore structure.The pressure-sensitive effect increased the proportion of mineral particles, such as quartz(the main component of the core skeleton), and reduced the proportion of clay minerals. The clay minerals were originally attached to the pore walls or interspersed in the pores; however, as the pressure increased, the clay minerals accumulated in the pores resulting in blockage of the pores. While simulating the multiphase displacement process, increasing the confining pressure was observed to severely restrict the flowability of oil and water. This study promises to improve the efficiency of reservoir development in terms of oil and gas exploitation. 展开更多
关键词 PRESSURE SENSITIVE - QEMSCAN MICRO-CT PORE network model MULTIPHASE flow
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Modeling and Generating Realistic Background Traffic by Hybrid Approach 被引量:2
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作者 QIAN Yaguan GUAN Xiaohui +1 位作者 JIANG Ming CEN Gang 《China Communications》 SCIE CSCD 2015年第10期147-157,共11页
One of the key challenges in largescale network simulation is the huge computation demand in fine-grained traffic simulation.Apart from using high-performance computing facilities and parallelism techniques,an alterna... One of the key challenges in largescale network simulation is the huge computation demand in fine-grained traffic simulation.Apart from using high-performance computing facilities and parallelism techniques,an alternative is to replace the background traffic by simplified abstract models such as fluid flows.This paper suggests a hybrid modeling approach for background traffic,which combines ON/OFF model with TCP activities.The ON/OFF model is to characterize the application activities,and the ordinary differential equations(ODEs) based on fluid flows is to describe the TCP congestion avoidance functionality.The apparent merits of this approach are(1) to accurately capture the traffic self-similarity at source level,(2) properly reflect the network dynamics,and(3) efficiently decrease the computational complexity.The experimental results show that the approach perfectly makes a proper trade-off between accuracy and complexity in background traffic simulation. 展开更多
关键词 network simulation background traffic ON/OFF models fluid flows self-similarity
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Quantitative model of trophic interactions in Beibu Gulf ecosystem in the northern South China Sea 被引量:5
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作者 CHEN Zuozhi QIU Yongsong JIA Xiaoping 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2006年第3期116-124,共9页
A mass-balanced model was constructed to determine the flow-energy in a community of fishes and invertebrates in the Beibu Gulf, northern South China Sea using Ecopath and Ecosim software. Input parameters were taken ... A mass-balanced model was constructed to determine the flow-energy in a community of fishes and invertebrates in the Beibu Gulf, northern South China Sea using Ecopath and Ecosim software. Input parameters were taken from the literature, except for the biomass of fish groups which was obtained from trawl surveys during October 1997 to May 1999 in the study area. The model consisted of 16 functional groups (boxes), including one marine mammal and seabirds, each representing organisms with a similar role in the food web, and only covered the main trophic flow in the Beibu Gulf ecosystem. The results showed that the food web of Beibu Gulf was dominated by the detrital path and benthic invertebrates played a significant role in transferring energy from the detritus to higher trophic levels; phytoplankton was a primary producer and most utilized as a food source. Fractional trophic levels ranged from 1.0 to 4.08 with marine mammals occupying the highest trophic level. Using network analysis, the system network was mapped into a linear food chain and six discrete trophic levels were found with a mean transfer efficiency of 16.7% from the detritus, 16.2% from the primary producer within the ecosystem. The biomass density of the commercially utilized species estimated by the model is 8.46 t/km^2, only O. 48% of the net primary production. 展开更多
关键词 trophic dynamics modeling energy flow network analysis Beibu Gulf ecosystem
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End-to-End Performance Evaluation of TCP Traffic under Multi-Queuing Networks 被引量:1
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作者 Jean Marie Garcia Mohamed El Hedi Boussada 《International Journal of Communications, Network and System Sciences》 2016年第6期219-233,共15页
While Internet traffic is currently dominated by elastic data transfers, it is anticipated that streaming applications will rapidly develop and contribute a significant amount of traffic in the near future. Therefore,... While Internet traffic is currently dominated by elastic data transfers, it is anticipated that streaming applications will rapidly develop and contribute a significant amount of traffic in the near future. Therefore, it is essential to understand and capture the relation between streaming and elastic traffic behavior. In this paper, we focus on developing simple yet effective approximations to capture this relationship. We study, then, an analytical model to evaluate the end-to-end performance of elastic traffic under multi-queuing system. This model is based on the fluid flow approximation. We assume that network architecture gives the head of priority to real time traffic and shares the remaining capacity between the elastic ongoing flows according to a specific weight. 展开更多
关键词 flow-Level modelling Multi-Queuing network Quality of Service Streaming Traffic Elastic Traffic
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Joint optimization scheduling for water conservancy projects incomplex river networks 被引量:6
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作者 Qin Liu Guo-hua Fang +1 位作者 Hong-bin Sun Xue-wen Wu 《Water Science and Engineering》 EI CAS CSCD 2017年第1期43-52,共10页
In this study, we simulated water flow in a water conservancy project consisting of various hydraulic structures, such as sluices, pumping stations, hydropower stations, ship locks, and culverts, and developed a multi... In this study, we simulated water flow in a water conservancy project consisting of various hydraulic structures, such as sluices, pumping stations, hydropower stations, ship locks, and culverts, and developed a multi-period and multi-variable joint optimization scheduling model for flood control, drainage, and irrigation. In this model, the number of sluice holes, pump units, and hydropower station units to be opened were used as decision variables, and different optimization objectives and constraints were considered. This model was solved with improved genetic algorithms and verified using the Huaian Water Conservancy Project as an example. The results show that the use of the joint optimization scheduling led to a 10% increase in the power generation capacity and a 15% reduction in the total energy consumption. The change in the water level was reduced by 0.25 m upstream of the Yundong Sluice, and by 50% downstream of pumping stations No. 1, No. 2, and No. 4. It is clear that the joint optimization scheduling proposed in this study can effectively improve power generation capacity of the project, minimize operating costs and energy consumption, and enable more stable operation of various hydraulic structures. The results may provide references for the management of water conservancy projects in complex river networks. 展开更多
关键词 Complex river network Water conservancy project Hydraulic structure flow capacity simulation Scheduling model Optimal scheduling
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碳达峰约束下中国工业隐含碳流动网络结构及演化 被引量:1
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作者 王兆华 王烁涵 +2 位作者 李浩 王淞 张爽 《管理评论》 北大核心 2025年第4期3-16,共14页
工业生产过程上下游行业之间高度相关联,厘清行业间的隐含碳流动规律对协同推动碳减排、实现工业碳达峰具有重要意义。本文在基于GRAS法编制2025年和2030年中国投入产出表的基础上,利用环境扩展的投入产出模型和社会网络分析方法揭示了2... 工业生产过程上下游行业之间高度相关联,厘清行业间的隐含碳流动规律对协同推动碳减排、实现工业碳达峰具有重要意义。本文在基于GRAS法编制2025年和2030年中国投入产出表的基础上,利用环境扩展的投入产出模型和社会网络分析方法揭示了2010—2030年中国工业行业内部以及与工业生产过程上下游的隐含碳流动网络结构与演变特征。研究结果表明,2010—2030年电力行业隐含碳排放呈快速上升趋势,石化、化工、非金属矿物制品和冶金行业的隐含碳排放降幅在8%~30%之间;在工业行业中,化工、非金属矿物制品和冶金是主要的隐含碳消费中心,电力、化工与专用设备制造是主要的隐含碳供给中心;电力、化工和专用设备制造承担了隐含碳流动网络中40%的中介作用。在碳达峰目标约束下,隐含碳网络中心逐渐向第三产业转移,电力、服务和交通成为隐含碳转移过程中的重要“桥梁”行业。 展开更多
关键词 工业行业 碳达峰 隐含碳流动 环境扩展的投入产出模型 网络结构
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A time sequence analysis on the informal information flow mechanism of microblogging
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作者 Yuan HU Xiaoli LIAO Andong WU 《Chinese Journal of Library and Information Science》 2011年第Z1期68-81,共14页
Microblog is a new Internet featured product, which has seen a rapid development in recent years. Researchers from different countries are making various technical analyses on microblogging applications. In this study... Microblog is a new Internet featured product, which has seen a rapid development in recent years. Researchers from different countries are making various technical analyses on microblogging applications. In this study, through using the natural language processing(NLP) and data mining, we analyzed the information content transmitted via a microblog, users' social networks and their interactions, and carried out an empirical analysis on the dissemination process of one particular piece of information via Sina Weibo.Based on the result of these analyses, we attempt to develop a better understanding about the rule and mechanism of the informal information flow in microblogging. 展开更多
关键词 Microblog Information flow model Social network Information dissemination
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基于无监督学习的快速小样本工业缺陷检测
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作者 李昕 李珊 《计算机与数字工程》 2025年第6期1763-1768,共6页
目前工业质量检测方面已有大量的研究工作,但在实际应用中,缺陷检测还存在较多问题。首先,工业生产的多样性和短周期,导致样本稀缺,使缺陷检测无法适应监督学习。其次,工业生产的流水线高效作业,导致缺陷检测对速度要求非常高。为了解... 目前工业质量检测方面已有大量的研究工作,但在实际应用中,缺陷检测还存在较多问题。首先,工业生产的多样性和短周期,导致样本稀缺,使缺陷检测无法适应监督学习。其次,工业生产的流水线高效作业,导致缺陷检测对速度要求非常高。为了解决这些问题,论文提出一种快速缺陷检测方法。通过使用无监督学习,结合空间转换网络,形成端到端的缺陷检测,实现了快速数据增强;同时使用累积分布函数改进流模型,提高模型映射能力,从而提高检测的准确率。实验结果证明,论文方法在小样本情况下,检测速度提升3倍~6倍,同时平均准确率与其他无监督方法相比也有所提升,实现效率和准确率的平衡,满足了工业生产的需求。 展开更多
关键词 缺陷检测 空间转换模块 流模型 无监督学习
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Fast Calculation Method of Energy Flow for Combined Electro-Thermal System and Its Application
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作者 Shuxin Liu Sai Dai +2 位作者 Qiang Ding Linxian Hu Qixiang Wang 《Energy and Power Engineering》 2017年第4期376-389,共14页
In recent years, Combined electro-thermal system has developed rapidly. In order to provide the initial data for the analysis of the combined electro-thermal system, a practical energy flow calculation method for the ... In recent years, Combined electro-thermal system has developed rapidly. In order to provide the initial data for the analysis of the combined electro-thermal system, a practical energy flow calculation method for the combined electro-thermal system is proposed in this paper. Based on the detailed analysis of the topology structure of the heating network and its hydraulic and thermodynamic model, the forward-backward sweep method for the heat flow of the heating network is established, which is more suitable for the actual radial heating network. The electric and thermal coupling model for heating source, such as thermoelectric unit and electric boiler is established, and the heat flow of heating network and the power flow of power grid are calculated orderly, thus a fast calculation method for the combined electro-thermal system is formed. What’s more, a combined electro-thermal system with two-stage peak-shaving electric boiler is used as the example system. This paper validates the effectiveness and rapidity of this method through the example system, and analyzes the influence for the energy flow of combined electro-thermal system caused by the operating parameters such as the installation location of electric boiler, the outlet water temperature of heat source and the outlet flow rate, etc. 展开更多
关键词 COMBINED Electro-Thermal System Energy flow RECURSIVE Heat flow model for Heating network Electric and THERMAL Coupling model
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