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Fuel loading pattern optimization of a pressurized water reactor by varying internal weights-based particle swarm optimization
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作者 Aneela Zameer Sikander M.Mirza +1 位作者 Asifullah Khan Furqan Mir 《Nuclear Science and Techniques》 SCIE CAS CSCD 2018年第3期61-70,共10页
Fuel reload pattern optimization is essential for attaining maximum fuel burnup for minimization of generation cost while minimizing power peaking factor(PPF).The aim of this work is to carry out detailed assessment o... Fuel reload pattern optimization is essential for attaining maximum fuel burnup for minimization of generation cost while minimizing power peaking factor(PPF).The aim of this work is to carry out detailed assessment of particle swarm optimization(PSO) in the context of fuel reload pattern search. With astronomically large number of possible loading patterns, the main constraints are limiting local power peaking factor, fixed number of assemblies,fixed fuel enrichment, and burnable poison rods. In this work, initial loading pattern of fixed batches of fuel assemblies is optimized by using particle swarm optimization technique employing novel feature of varying inertial weights with the objective function to obtain both flat power profile and cycle k_(eff)>1. For neutronics calculation, PSU-LEOPARD-generated assembly depletiondependent group-constant-based ADD files are used. The assembly data description file generated by PSU-LEOPARD is used as input cross-section library to MCRAC code, which computes normalized power profile of all fuel assemblies of PWR nuclear reactor core. The standard PSO with varying inertial weights is then employed to avoid trapping in local minima. A series of experiments havebeen conducted to obtain near-optimal converged fuelloading pattern of 300 MWe PWR Chashma reactor. The optimized loading pattern is found in good agreement with results found in literature. Hybrid scheme of PSO with simulated annealing has also been implemented and resulted in faster convergence. 展开更多
关键词 PWR Loading pattern optimization PSO PPF In-core FUEL management
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Optimization of horizontal well staggered patterns
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作者 Zhao Chunsen Li Peijing Guan Dan Liu Qingjuan 《Petroleum Science》 SCIE CAS CSCD 2008年第4期348-352,共5页
Staggered line-drive patterns are widely used in oilfields. In this paper, to optimize a staggered pattern of horizontal wells, a 3D problem was divided into two 2D (x-y plane andy-z plane) problems with the pseudo-... Staggered line-drive patterns are widely used in oilfields. In this paper, to optimize a staggered pattern of horizontal wells, a 3D problem was divided into two 2D (x-y plane andy-z plane) problems with the pseudo-3D method, conformal transformation and superposition principle. A productivity equation for a horizontal well was deduced, which can be used to optimize the well pattern. A relationship between the length of horizontal wells and the shape factor of well patterns was established. The result shows that optimized well patterns can improve oil production from horizontal wells. This provides a theoretical basis for horizontal well applications to the development of oilfields, especially for overall development of oilfields by horizontal wells. 展开更多
关键词 Horizontal well productivity calculation optimization of well pattern
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Beam Pattern Synthesis Based on Hybrid Optimization Algorithm
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作者 郁彦利 王英民 李磊 《Defence Technology(防务技术)》 SCIE EI CAS 2010年第3期171-176,共6页
As conventional methods for beam pattern synthesis can not always obtain the desired optimum pattern for the arbitrary underwater acoustic sensor arrays,a hybrid numerical synthesis method based on adaptive principle ... As conventional methods for beam pattern synthesis can not always obtain the desired optimum pattern for the arbitrary underwater acoustic sensor arrays,a hybrid numerical synthesis method based on adaptive principle and genetic algorithm was presented in this paper.First,based on the adaptive theory,a given array was supposed as an adaptive array and its sidelobes were reduced by assigning a number of interference signals in the sidelobe region.An initial beam pattern was obtained after several iterations and adjustments of the interference intensity,and based on its parameters,a desired pattern was created.Then,an objective function based on the difference between the designed and desired patterns can be constructed.The pattern can be optimized by using the genetic algorithm to minimize the objective function.A design example for a double-circular array demonstrates the effectiveness of this method.Compared with the approaches existing before,the proposed method can reduce the sidelobe effectively and achieve less synthesis magnitude error in the mainlobe.The method can search for optimum attainable pattern for the specific elements if the desired pattern can not be found. 展开更多
关键词 information processing array beam pattern synthesis genetic algorithm optimization
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Recognition model and algorithm of projectiles by combining particle swarm optimization support vector and spatial-temporal constrain 被引量:1
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作者 Han-shan Li 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第9期273-283,共11页
In order to improve the recognition rate and accuracy rate of projectiles in six sky-screens intersection test system,this work proposes a new recognition method of projectiles by combining particle swarm optimization... In order to improve the recognition rate and accuracy rate of projectiles in six sky-screens intersection test system,this work proposes a new recognition method of projectiles by combining particle swarm optimization support vector and spatial-temporal constrain of six sky-screens detection sensor.Based on the measurement principle of the six sky-screens intersection test system and the characteristics of the output signal of the sky-screen,we analyze the existing problems regarding the recognition of projectiles.In order to optimize the projectile recognition effect,we use the support vector machine and basic particle swarm algorithm to form a new recognition algorithm.We set up the particle swarm algorithm optimization support vector projectile information recognition model that conforms to the six sky-screens intersection test system.We also construct a spatial-temporal constrain matching model based on the spatial geometric relationship of six sky-screen intersection,and form a new projectile signal recognition algorithm with six sky-screens spatial-temporal information constraints under the signal classification mechanism of particle swarm optimization algorithm support vector machine.Based on experiments,we obtain the optimal penalty and kernel function radius parameters in the PSO-SVM algorithm;we adjust the parameters of the support vector machine model,train the test signal data of every sky-screen,and gain the projectile signal classification results.Afterwards,according to the signal classification results,we calculate the coordinate parameters of the real projectile by using the spatial-temporal constrain of six sky-screens detection sensor,which verifies the feasibility of the proposed algorithm. 展开更多
关键词 Six sky-screens intersection test system pattern recognition Particle swarm optimization Support vector machine PROJECTILE
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Insight into evolution of invasive patterns on fingering phenomenon during immiscible two-phase flow through pore structure
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作者 Yu Li Hui-Qing Liu +3 位作者 Chao Peng Peng Jiao Wai Lam Loh Qing Wang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第5期3307-3325,共19页
Understanding fingering, as a challenge to stable displacement during the immiscible flow, has become a crucial phenomenon for geological carbon sequestration, enhanced oil recovery, and groundwater protection. Typica... Understanding fingering, as a challenge to stable displacement during the immiscible flow, has become a crucial phenomenon for geological carbon sequestration, enhanced oil recovery, and groundwater protection. Typically governed by gravity, viscous and capillary forces, these factors lead invasive fluids to occupy pore space irregularly and incompletely. Previous studies have demonstrated capillary numbers,describing the viscous and capillary forces, to quantificationally induce evolution of invasion patterns.While the evolution mechanisms of invasive patterns have not been deeply elucidated under the constant capillary number and three variable parameters including velocity, viscosity, and interfacial tension.Our research employs two horizontal visualization systems and a two-phase laminar flow simulation to investigate the tendency of invasive pattern transition by various parameters at the pore scale. We showed that increasing invasive viscosity or reducing interfacial tension in a homogeneous pore space significantly enhanced sweep efficiency, under constant capillary number. Additionally, in the fingering crossover pattern, the region near the inlet was prone to capillary fingering with multi-directional invasion, while the viscous fingering with unidirectional invasion was more susceptible occurred in the region near the outlet. Furthermore, increasing invasive viscosity or decreasing invasive velocity and interfacial tension promoted the extension of viscous fingering from the outlet to the inlet, presenting that the subsequent invasive fluid flows toward the outlet. In the case of invasive trunk along a unidirectional path, the invasive flow increased exponentially closer to the outlet, resulting in a significant decrease in the width of the invasive interface. Our work holds promising applications for optimizing invasive patterns in heterogeneous porous media. 展开更多
关键词 Immiscible two-phase flow Fingering phenomenon Invasive pattern Capillary number Parameters optimization
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“农文旅+”融合背景下休闲农业专业人才培养模式的优化研究
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作者 乔扬 韦庆翠 +1 位作者 张衡锋 曲良谱 《安徽农业科学》 2025年第5期259-262,共4页
随着“农文旅+”融合背景下的休闲农业专业人才培养模式的兴起,休闲农业领域对专业人才的需求日益增长,但现有的人才培养体系未能充分满足市场需求。在“农文旅+”融合发展背景下,针对性地提出了休闲农业专业人才培养模式的优化策略,旨... 随着“农文旅+”融合背景下的休闲农业专业人才培养模式的兴起,休闲农业领域对专业人才的需求日益增长,但现有的人才培养体系未能充分满足市场需求。在“农文旅+”融合发展背景下,针对性地提出了休闲农业专业人才培养模式的优化策略,旨在通过优化课程体系、实践教学体系、产教融合机制和创新能力培养,提升休闲农业人才培养的质量和效果,以适应农文旅融合发展的需求。 展开更多
关键词 农文旅 休闲农业 人才培养 模式优化
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基于人机协同的皮裤版型舒适性优化设计
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作者 朱江晖 叶欣雨 +2 位作者 王懂浩 张爱琳 张璐璐 《中国皮革》 2025年第3期100-105,共6页
随着服装产业数智化转型的推进,人机协同已成为服装设计领域提升研发效率的有效途径。针对女式合体皮裤的压力舒适性问题,采用人机协同的方法,将服装设计师的专业经验与CLO3D虚拟试衣系统的智能分析相结合,对皮裤版型进行舒适性优化。... 随着服装产业数智化转型的推进,人机协同已成为服装设计领域提升研发效率的有效途径。针对女式合体皮裤的压力舒适性问题,采用人机协同的方法,将服装设计师的专业经验与CLO3D虚拟试衣系统的智能分析相结合,对皮裤版型进行舒适性优化。通过对虚拟人体身着皮裤在站立、坐立和行走3种状态下测量13个关键部位的压力值,分析压力分布与版型舒适性之间的关系,指导皮裤版型的舒适性优化。结果表明,在人机协同下优化后的版型在多个测试点上均表现出更好的舒适性,能够满足现代女性对皮裤舒适度的需求。为推动服装数智化设计和定制化发展提供了新的理论依据和实践参考。 展开更多
关键词 人机协同 皮裤 CLO3D 压力舒适性 版型优化
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Research on Short-Term Electric Load Forecasting Using IWOA CNN-BiLSTM-TPA Model
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作者 MEI Tong-da SI Zhan-jun ZHANG Ying-xue 《印刷与数字媒体技术研究》 北大核心 2025年第1期179-187,共9页
Load forecasting is of great significance to the development of new power systems.With the advancement of smart grids,the integration and distribution of distributed renewable energy sources and power electronics devi... Load forecasting is of great significance to the development of new power systems.With the advancement of smart grids,the integration and distribution of distributed renewable energy sources and power electronics devices have made power load data increasingly complex and volatile.This places higher demands on the prediction and analysis of power loads.In order to improve the prediction accuracy of short-term power load,a CNN-BiLSTMTPA short-term power prediction model based on the Improved Whale Optimization Algorithm(IWOA)with mixed strategies was proposed.Firstly,the model combined the Convolutional Neural Network(CNN)with the Bidirectional Long Short-Term Memory Network(BiLSTM)to fully extract the spatio-temporal characteristics of the load data itself.Then,the Temporal Pattern Attention(TPA)mechanism was introduced into the CNN-BiLSTM model to automatically assign corresponding weights to the hidden states of the BiLSTM.This allowed the model to differentiate the importance of load sequences at different time intervals.At the same time,in order to solve the problem of the difficulties of selecting the parameters of the temporal model,and the poor global search ability of the whale algorithm,which is easy to fall into the local optimization,the whale algorithm(IWOA)was optimized by using the hybrid strategy of Tent chaos mapping and Levy flight strategy,so as to better search the parameters of the model.In this experiment,the real load data of a region in Zhejiang was taken as an example to analyze,and the prediction accuracy(R2)of the proposed method reached 98.83%.Compared with the prediction models such as BP,WOA-CNN-BiLSTM,SSA-CNN-BiLSTM,CNN-BiGRU-Attention,etc.,the experimental results showed that the model proposed in this study has a higher prediction accuracy. 展开更多
关键词 Whale optimization Algorithm Convolutional Neural Network Long Short-Term Memory Temporal pattern Attention Power load forecasting
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县域国土空间时空格局演变的元胞自动机模型类比研究
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作者 闫旭 张晓瑞 董洁云 《城市勘测》 2025年第1期38-45,共8页
为探究各类土地利用格局演变模拟预测模型对县级行政区域进行模拟与优化的适应程度和各自特征,采用以基于纯净地理元胞自动机的FLUS、PLUS模型以及基于混合亚元胞的MCCA模型对同一县级行政区域进行国土空间格局演变模拟,通过以上3类模... 为探究各类土地利用格局演变模拟预测模型对县级行政区域进行模拟与优化的适应程度和各自特征,采用以基于纯净地理元胞自动机的FLUS、PLUS模型以及基于混合亚元胞的MCCA模型对同一县级行政区域进行国土空间格局演变模拟,通过以上3类模型对土地利用转移机制的挖掘、历史时期的模拟精度、未来时期的模拟优化情况及精度验证结果,表明FLUS模型在预测中微观尺度区域及特定场景下的精度可能高于PLUS,但在类似跳跃式、飞地型发展的预测则明显弱于PLUS模型,MCCA模型则在各类模拟中总体表现较好。 展开更多
关键词 土地覆被变化 FLUS PLUS MCCA 逻辑回归 MARKOV 格局优化 来安县
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基于CMIP6模式降水的河北省滑坡灾害风险变化预测研究
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作者 林诚杰 王洁 +3 位作者 梁峰铭 季静静 谈松林 刘宇 《中国农村水利水电》 北大核心 2025年第1期201-208,214,共9页
为探究未来气候变化下河北省滑坡灾害发生的变化规律,从而对防灾减灾的统筹规划提供科学的依据,使得人们更能规避滑坡灾害带来的危害风险,运用ENMeval算法(Ecological Niche Modeling evaluation Algorithm,ENMeval)对最大熵模型(Maximu... 为探究未来气候变化下河北省滑坡灾害发生的变化规律,从而对防灾减灾的统筹规划提供科学的依据,使得人们更能规避滑坡灾害带来的危害风险,运用ENMeval算法(Ecological Niche Modeling evaluation Algorithm,ENMeval)对最大熵模型(Maximum Entropy Model,MaxEnt)进行优化,基于调查、收集到的860个滑坡灾害点和影响灾害的11个因子,在探讨主要影响因子的基础上进行滑坡灾害风险评估,并结合未来(近期:2041-2060年、中期:2061-2080年、远期:2081-2100年)三期气候数据的3种辐射强迫情景模式(低等强迫情景:SSP126、中高等强迫情景:SSP370、高等强迫情景:SSP585),预测滑坡灾害潜在风险区的空间分布格局和变化规律。结果表明:(1)经过优化的MaxEnt模型的AUC值(Area Under the Curve,AUC)在0.9以上,说明该模型在预测滑坡灾害潜在风险区方面表现出色。(2)通过优化Maxent模型计算的综合贡献率分析,确定影响滑坡灾害的主要因子依次为:最湿季度降水量、最湿月降水量、高程和降雨量季节变异系数,这表明降水相关的因子是影响滑坡发生的最主要因素。(3)对14个CMIP6气候模式(Coupled Model Intercomparison Project Phase 6,CMIP6)数据进行综合评估,得出BCC-CSM2-MR在降水方面相比其他气候模式,具有最优的模拟能力,其次是CMCC-ESM2和ACCESS-CM2。(4)在未来气候强迫情景下,滑坡灾害低风险区面积均有所下降,中、中高、高风险区的面积占比均有所增加,这和未来降水量的变化预测趋势相同。 展开更多
关键词 滑坡灾害 模型优化 气候模式 风险预测
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汾河平原某田-沟-塘系统中氮磷迁移转化规律及适宜水面率研究
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作者 刘帅 《广东水利电力职业技术学院学报》 2025年第1期28-32,共5页
种植作物过程中施用的大量农药和化肥只有部分作用到作物,大部分随农田排水流入到附近水体,形成面源污染。对此,通过对某试验区作物长期灌溉、降雨期间田、沟、塘水体中的氮磷含量取样分析,研究氮磷物质在田、沟、塘的迁移转化规律,提... 种植作物过程中施用的大量农药和化肥只有部分作用到作物,大部分随农田排水流入到附近水体,形成面源污染。对此,通过对某试验区作物长期灌溉、降雨期间田、沟、塘水体中的氮磷含量取样分析,研究氮磷物质在田、沟、塘的迁移转化规律,提出适宜水面率。并根据耕作和节水减排要求,提出田间工程建设要求和田-沟-塘(湿地)系统建设模式。结果表明,沟道和塘堰对农田氮磷元素具有一定净化拦截效果,合理规划设置田-沟-塘系统可以提高营养元素利用率,降低污染。研究结果可为土地生态整治的田间工程建设提供参考。 展开更多
关键词 田-沟-塘系统 迁移转化规律 适宜水面率
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东北黑土区土地利用景观格局最佳粒度分析
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作者 李海洋 李巍 贺健勇 《安徽农业科学》 2025年第6期63-65,73,共4页
利用松原市2021年的遥感影像、土地利用图、行政区划图以及相关统计数据,在RS与GIS的技术支持下,采用GIS空间分析、景观格局指数研究、面积损失评价方法等来确定景观格局分析的最佳粒度。结果表明:松原市景观的最佳分析粒度为90 m。分... 利用松原市2021年的遥感影像、土地利用图、行政区划图以及相关统计数据,在RS与GIS的技术支持下,采用GIS空间分析、景观格局指数研究、面积损失评价方法等来确定景观格局分析的最佳粒度。结果表明:松原市景观的最佳分析粒度为90 m。分析景观格局指数随粒度变化的响应得到整体适宜粒度域为90~150 m,利用面积损失评价方法在粒度为90 m时,土地面积变化指数最小,此时面积精度损失最少,所以确定最佳分析粒度为90 m。 展开更多
关键词 最佳分析粒度 土地利用 景观格局 东北黑土区
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单侧渐扩消力池体型优化与水力特性分析
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作者 石林平 廖智颖 +2 位作者 谢志高 周训成 涂向阳 《人民珠江》 2025年第1期103-109,共7页
东涌水库溢洪道采用泄槽台阶消能+下游消力池底流消能的工程方案,但受限于地形地质条件,消力池宽度较窄,与河道呈145°夹角,且下游现状交通桥阻碍行洪,不利因素较多。原方案泄流进入消力池后,池内水面波动大,出池水流大幅加速,河道... 东涌水库溢洪道采用泄槽台阶消能+下游消力池底流消能的工程方案,但受限于地形地质条件,消力池宽度较窄,与河道呈145°夹角,且下游现状交通桥阻碍行洪,不利因素较多。原方案泄流进入消力池后,池内水面波动大,出池水流大幅加速,河道内主流集中,交通桥上游左侧形成大范围回流区。通过水工模型试验,对消力池布置方案进行优化。结果表明:通过加深消力池、池内前段设T型墩、左偏消力池左侧边墙、降低尾坎起反坡至河道等措施,水流流态明显改善。泄流入池后水面波动幅度减小,出池水流不再加速,河道内水流分散、流速减缓。研究成果可为类似工程提供借鉴。 展开更多
关键词 溢洪道 单侧渐扩消力池 T型墩 水工模型 流态优化
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Optimizing Control for Rotor Vibration with Magnetorheological Fluid Damper 被引量:3
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作者 邢健 何立东 王锎 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2014年第5期538-545,共8页
The aim of this work is to analyze and design a control system for vibration reduction in a rotor system using a shear mode magnetorheological fluid(MRF)damper.A dynamic model of the MRF damper-rotor system was built ... The aim of this work is to analyze and design a control system for vibration reduction in a rotor system using a shear mode magnetorheological fluid(MRF)damper.A dynamic model of the MRF damper-rotor system was built and simulated in Matlab/Simulink to analyze the rotor vibration characteristics and the vibration reduction effect of the MRF damper.Based on the numerical simulation analysis,an optimizing control strategy using pattern search method was proposed and designed.The control system was constructed on a test rotor bench and experiment validations on the effectiveness of the proposed control strategy were conducted.Experimental results show that rotor vibration caused by unbalance can be well controlled whether in resonance region(70%)or in non-resonance region(30%).An irregular vibration amplitude jump can be suppressed with the optimization strategy.Furthermore,it is found that the rapidity of transient response and efficiency of optimizing technique depend on the pattern search step.The presented strategies and control system can be extended to multi-span(more than two or three spans)rotor system.It provides a powerful technical support for the extension and application in target and control for shafting vibration. 展开更多
关键词 magnetorheological fluid damper optimizing control pattern search method vibration reduction
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Experiments on the influences of well pattern on water flooding characteristics of dissolution vug-cave reservoir
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作者 WANG Jing LIU Huiqing +4 位作者 ZHANG Jing ZHAO Wei HUANG Yitao KANG Zhijiang ZHENG Songqing 《Petroleum Exploration and Development》 2018年第6期1103-1111,共9页
Based on the similarity criterion, volcanic rock samples were taken from outcrops to make experimental models. Water flooding experiments of five-spot well pattern, nine-spot well pattern, five-spot to nine-spot well ... Based on the similarity criterion, volcanic rock samples were taken from outcrops to make experimental models. Water flooding experiments of five-spot well pattern, nine-spot well pattern, five-spot to nine-spot well pattern, the relationship between relative well and fracture positions, and injection rate in dissolution vug-cave reservoirs with/without fractures were carried out to analyze variation regularities of development indexes, find out development characteristics of water flooding with different well patterns and sort out the optimal water flooding development mode. For dissolution vug-cave reservoirs without fractures, five-spot well pattern waterflooding has very small sweeping area, serious water channeling and low oil recovery. When the well pattern was adjusted from five-spot to nine-spot well pattern, oil recovery could be largely improved, but the corner well far from the injector is little affected. In dissolution vug-cave reservoirs with fractures, when the injector and producer are not connected by fractures, the fractures could effectively connect the poorly linked vugs to improve the development effect of water flooding. Whether there are fractures or not in dissolution vug-cave reservoirs, the development effect of nine-spot well-pattern is much better than that of five-spot well pattern and five-spot to nine-spot well pattern, this is more evident when there are fractures, and the edge well has better development indexes than corner well. At the high-water cut stage of water flooding with nine-spot well pattern, the oil recovery can be further improved with staggered line-drive pattern by converting the corner well into injection well. It is helpful to increase the oil production of corner well of nine-spot well pattern by increasing the injection rate, and improve ultimate oil recovery, but the water-free production period would be greatly shortened and water-free recovery would decrease. 展开更多
关键词 similarity criterion DISSOLUTION vug-cave RESERVOIR water FLOODING injection-production WELL pattern WELL placement INJECTION rate development index oil recovery
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基于遗传算法优化Canny算子的织绣文物纹样抽取方法研究 被引量:2
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作者 张宇 张健 齐林 《丝绸》 CAS CSCD 北大核心 2024年第6期1-12,共12页
织绣文物中的纹样彰显中国传统文化造型艺术的形式美感,是文创设计的重要素材源泉。针对传统Canny算子进行纹样边缘检测需人为确定阈值的问题,本文提出基于遗传算法自适应优化Canny算子阈值的方法,将边缘点、非边缘点类间梯度幅值方差... 织绣文物中的纹样彰显中国传统文化造型艺术的形式美感,是文创设计的重要素材源泉。针对传统Canny算子进行纹样边缘检测需人为确定阈值的问题,本文提出基于遗传算法自适应优化Canny算子阈值的方法,将边缘点、非边缘点类间梯度幅值方差设置为适应度函数,通过格雷码对阈值染色体编解码、锦标赛选择算法优选交叉变异后的阈值,求解最优适应度对应的高低阈值,用于纹样边缘检测;此外,运用形态学操作得到纹样的完整、精确轮廓;最后,添加Alpha通道抽取纹样前景。实验表明,上述方法在织绣纹样抽取精度和像素准确度(PA)上,优于传统Canny算子、混合蛙跳自适应Canny算子、Otsu法优化Canny算子等已有方法,可有效检测织绣文物图像中纹样真实边缘并完成纹样抽取。 展开更多
关键词 织绣文物 遗传算法 CANNY算子 边缘检测 纹样抽取 最优阈值
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中深层水热型地热资源集群式开发井位部署参数研究与应用——以HTC地热田为例
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作者 盖长城 赵忠新 +2 位作者 任路 颜艺灿 侯本峰 《油气藏评价与开发》 CSCD 北大核心 2024年第4期638-646,共9页
在中国“双碳”战略背景下,清洁能源的高效开发利用逐渐成为各行业关注的焦点,而中深层水热型地热资源是一种储量丰富、运行稳定、绿色环保的清洁能源。近年来,随着地热资源开发利用程度逐渐增加,开发模式逐渐向集群式发展,相比以往的... 在中国“双碳”战略背景下,清洁能源的高效开发利用逐渐成为各行业关注的焦点,而中深层水热型地热资源是一种储量丰富、运行稳定、绿色环保的清洁能源。近年来,随着地热资源开发利用程度逐渐增加,开发模式逐渐向集群式发展,相比以往的分布式开发模式,集群式开发具有经济、稳定、抗风险能力高、改扩建能力强等优点。但开发模式、采灌井网、采灌井距等关键参数仍在探索阶段,这些参数对集群式开发影响明显,亟须对此开展机理研究、优化关键参数。以HTC地热田作为研究对象,利用数值模拟技术,耦合地下温度场、压力场、水流场建立数学模型,分析不同开发模式、采灌井网、采灌井距条件下地下温度场、压力场、水流场变化规律,确定最优参数,指导矿场生产。实践证实,该方法可有效保障地热开发项目稳定运行,实现地热开发项目经济效益最优化。 展开更多
关键词 中深层水热型地热资源 集群式开发 数值模拟 开发模式优化 井网优化 井距优化
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电力管廊通风规律及结构布局优化研究
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作者 高峰 姚海波 +3 位作者 耿英宸 冯天垚 庄璐 于贺 《隧道建设(中英文)》 CSCD 北大核心 2024年第S01期156-166,共11页
为改善电力管廊的通风效果,依托北京新机场高速公路综合管廊工程,采用数值分析与现场试验的方法,对电力舱通风规律进行系统研究。在得到初步规律的基础上,通过改变通风方式、通风口位置和电缆布局,对比研究机械进风自然排风和自然进风... 为改善电力管廊的通风效果,依托北京新机场高速公路综合管廊工程,采用数值分析与现场试验的方法,对电力舱通风规律进行系统研究。在得到初步规律的基础上,通过改变通风方式、通风口位置和电缆布局,对比研究机械进风自然排风和自然进风机械排风、通风口设在管廊顶部和两侧、10 k V和110 k V电缆交换位置3类6种工况下的通风效果。结果表明:1)现有正常通风条件下,从进风口到排风口,进风口处气流组织混乱;同时,由于在进风口处气流2次改变运动方向导致能量损失很大,致使可用于驱动管廊内空气的能量减小,通风效果下降,造成能源浪费。2)将通风口(风机)布置在电力舱两侧时,因初始风速与通风方向一致,避免了能量损失,有效提高了通风效果。研究显示,管廊中间断面的平均风速提高了0.31 m/s,变幅达39.6%;温度降低了1.6℃,变幅达6.1%;压力损失降低了13.7 Pa,变幅达30.4%,极大地改善了电力舱通风效果。3)在通风口(风机)位于顶部的条件下,对电缆布局优化后,10 k V电缆表面温度降低3.21℃,110 k V电缆表面温度升高1.68℃,纵断面平均温度下降0.365℃,电缆布局调整有利于降低舱内温度,减少压力损失。 展开更多
关键词 电力管廊 通风规律 数值模拟 通风优化
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融合改进NBEATSx和时间注意力机制的空气污染预测
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作者 李杰 王占刚 《陕西科技大学学报》 北大核心 2024年第5期198-205,共8页
针对现有空气污染预测存在结构复杂、对多元变量与不同时间步间依赖关系提取不充分和多步预测精度低的问题,引入了β分布和非线性动态控制函数改进星鸦优化算法(INOA),优化NBEATSx模型参数,提高收敛精度;并融合时间模式注意力机制(TPA)... 针对现有空气污染预测存在结构复杂、对多元变量与不同时间步间依赖关系提取不充分和多步预测精度低的问题,引入了β分布和非线性动态控制函数改进星鸦优化算法(INOA),优化NBEATSx模型参数,提高收敛精度;并融合时间模式注意力机制(TPA)为不同时间尺度的多外生变量自适应分配权重,再结合预测因子获取时间模式关系.利用所提模型对北京地区的PM2.5进行预测,与传统模型相比精度提高超过18.45%,为空气污染预测提供了一种新方法. 展开更多
关键词 空气污染预测 时间模式注意力机制 星鸦优化算法 神经基扩展分析网络
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水网格局下的苏南乡村聚落空间生态适应性机制与优化路径研究
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作者 于淼 陆建城 《苏州科技大学学报(工程技术版)》 CAS 2024年第4期68-75,共8页
生态文明视阈下,乡村聚落空间是现代化生态规划实践的重要抓手和优化配置生态资源的基本单元。在气候变化及乡村生态问题日益严峻和紧迫的背景下,本文梳理了在水网格局的影响下,乡村聚落空间的三种现状布局模式,并从水网耦合度、自然格... 生态文明视阈下,乡村聚落空间是现代化生态规划实践的重要抓手和优化配置生态资源的基本单元。在气候变化及乡村生态问题日益严峻和紧迫的背景下,本文梳理了在水网格局的影响下,乡村聚落空间的三种现状布局模式,并从水网耦合度、自然格局、功能空间、建筑景观和基础设施五个方面剖析了生态缺失的现状问题。从“内生动力、外部推动、差异化和多尺度引导”等四个角度,探索苏南水网地区乡村聚落空间的生态适应性机制,寻求水网格局下乡村聚落空间生态适应性的目标、原则和要素。凝炼适用于该地区生态环境和现代农村生产、生活条件的聚落空间规划的生态适应性优化路径,包括梳理图底耦合的水-乡格局、建构系统综合的功能空间、建设乡土化的建筑与景观和基础设施的近自然处理等。 展开更多
关键词 水网格局 乡村聚落空间 生态适应性 机制 优化路径
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