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Operational optimization of copper flotation process based on the weighted Gaussian process regression and index-oriented adaptive differential evolution algorithm
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作者 Zhiqiang Wang Dakuo He Haotian Nie 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期167-179,共13页
Concentrate copper grade(CCG)is one of the important production indicators of copper flotation processes,and keeping the CCG at the set value is of great significance to the economic benefit of copper flotation indust... Concentrate copper grade(CCG)is one of the important production indicators of copper flotation processes,and keeping the CCG at the set value is of great significance to the economic benefit of copper flotation industrial processes.This paper addresses the fluctuation problem of CCG through an operational optimization method.Firstly,a density-based affinity propagationalgorithm is proposed so that more ideal working condition categories can be obtained for the complex raw ore properties.Next,a Bayesian network(BN)is applied to explore the relationship between the operational variables and the CCG.Based on the analysis results of BN,a weighted Gaussian process regression model is constructed to predict the CCG that a higher prediction accuracy can be obtained.To ensure the predicted CCG is close to the set value with a smaller magnitude of the operation adjustments and a smaller uncertainty of the prediction results,an index-oriented adaptive differential evolution(IOADE)algorithm is proposed,and the convergence performance of IOADE is superior to the traditional differential evolution and adaptive differential evolution methods.Finally,the effectiveness and feasibility of the proposed methods are verified by the experiments on a copper flotation industrial process. 展开更多
关键词 Weighted Gaussian process regression Index-oriented adaptive differential evolution operational optimization Copper flotation process
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Evaluation of the effectiveness of preventive nursing measures for pressure injuries in patients in the neurology intensive care unit
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作者 Rong Zhang Peng-Xin Ma Juan-Juan Zhang 《World Journal of Clinical Cases》 SCIE 2024年第19期3807-3814,共8页
BACKGROUND Patients in neurology intensive care units(ICU)are prone to pressure injuries(PU)due to factors such as severe illness,long-term bed rest,and physiological dysfunction.PU not only causes pain and complicati... BACKGROUND Patients in neurology intensive care units(ICU)are prone to pressure injuries(PU)due to factors such as severe illness,long-term bed rest,and physiological dysfunction.PU not only causes pain and complications to patients,but also increases medical burden,prolongs hospitalization time,and affects the recovery process.AIM To evaluate and optimize the effectiveness of pressure injury prevention nursing measures in neurology ICU patients.METHODS A retrospective study was conducted,and 60 patients who were admitted to the ICU of the Department of Neurology were selected and divided into an observation group and a control group according to the order of admission,with 30 people in each group.The observation group implemented pressure injury prevention and nursing measures,while the control group adopted routine care.RESULTS Comparison between observation and control groups following pressure injury prevention nursing intervention revealed significantly lower incidence rates in the observation group compared to the control group at 48 h(8.3%vs 26.7%),7 d(16.7%vs 43.3%),and 14 d(20.0%vs 50.0%).This suggests a substantial reduction in pressure injury incidence in the observation group,with the gap widening over time.Additionally,patients in the observation group exhibited quicker recovery,with a shorter average time to get out of bed(48 h vs 72 h)and a shorter average length of stay(12 d vs 15 d)compared to the control group.Furthermore,post-intervention,patients in the observation group reported significantly improved quality of life scores,including higher scores in body satisfaction,feeling and function,and comfort(both psychological and physiological),indicating enhanced overall well-being and comfort following the implementation of pressure injury prevention nursing measures.CONCLUSION Implementing pressure injury preventive care measures for neurology ICU patients will have better results. 展开更多
关键词 Neurology intensive care units Pressure injury Preventive care Effect evaluation optimization research Prognostic effect
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Optimal scheduling of a township integrated-energy system using the adjustable heat-electricity ratio model
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作者 Quan Chen Jingyi Wang +4 位作者 Min Cang Xiaomeng Zhai Xi Cheng Shuang Wu Dongwei Li 《Global Energy Interconnection》 EI CSCD 2024年第1期48-60,共13页
With the expansion and implementation of rural revitalization strategies,there is a constant need for new energy sources for the construction of new townships.Consequently,integrated energy systems with the interconne... With the expansion and implementation of rural revitalization strategies,there is a constant need for new energy sources for the construction of new townships.Consequently,integrated energy systems with the interconnection and interaction of multiple energy sources are developing rapidly.Biomass energy,a renewable green energy source with low pollution and wide distribution,has significant application potential in integrated energy systems.Considering the application of biomass energy in townships,this study established an integrated biomass energy system and proposed a model to optimize its operation.Lowest economic cost and highest clean energy utilization rate were considered as the objective functions.In addition,a plan was suggested to adjust the heat-electricity ratio based on the characteristics of the combined heat and power of the biomass.Finally,a simulation analysis conducted for a town in China was discussed,demonstrating that the construction of a township integrated-energy system and the use of biomass can significantly reduce operating costs and improve the energy utilization rate.Moreover,by adjusting the heat-electricity ratio,the economic cost was further reduced by 6.70%,whereas the clean energy utilization rate was increased by 5.14%. 展开更多
关键词 Biomass energy Integrated-energy system Afterburning device Heat-electricity ratio operation optimization
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A Multi-Objective Optimization for Locating Maintenance Stations and Operator Dispatching of Corrective Maintenance
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作者 Chao-Lung Yang Melkamu Mengistnew Teshome +1 位作者 Yu-Zhen Yeh Tamrat Yifter Meles 《Computers, Materials & Continua》 SCIE EI 2024年第6期3519-3547,共29页
In this study,we introduce a novel multi-objective optimization model tailored for modern manufacturing,aiming to mitigate the cost impacts of operational disruptions through optimized corrective maintenance.Central t... In this study,we introduce a novel multi-objective optimization model tailored for modern manufacturing,aiming to mitigate the cost impacts of operational disruptions through optimized corrective maintenance.Central to our approach is the strategic placement of maintenance stations and the efficient allocation of personnel,addressing a crucial gap in the integration of maintenance personnel dispatching and station selection.Our model uniquely combines the spatial distribution of machinery with the expertise of operators to achieve a harmonious balance between maintenance efficiency and cost-effectiveness.The core of our methodology is the NSGA Ⅲ+Dispatch,an advanced adaptation of the Non-Dominated Sorting Genetic Algorithm Ⅲ(NSGA-Ⅲ),meticulously designed for the selection of maintenance stations and effective operator dispatching.This method integrates a comprehensive coding process,crossover operator,and mutation operator to efficiently manage multiple objectives.Rigorous empirical testing,including a detailed analysis from a Taiwan Residents electronic equipment manufacturer,validated the effectiveness of our approach across various scenarios of machine failure frequencies and operator configurations.The findings reveal that the proposed model significantly outperforms current practices by reducing response times by up to 23%in low-frequency and 28.23%in high-frequency machine failure scenarios,leading to notable improvements in efficiency and cost reduction.Additionally,it demonstrates significant improvements in oper-ational efficiency,particularly in selective high-frequency failure contexts,while ensuring substantial manpower cost savings without compromising on operational effectiveness.This research significantly advances maintenance strategies in production environments,providing the manufacturing industry with practical,optimized solutions for diverse machine malfunction situations.Furthermore,the methodologies and principles developed in this study have potential applications in various other sectors,including healthcare,transportation,and energy,where maintenance efficiency and resource optimization are equally critical. 展开更多
关键词 Corrective maintenance multi-objective optimization non-dominated sorting genetic algorithmⅢ operator allocation maintenance station location
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Key Issues for Modelling, Operation, Management and Diagnosis of Lithium Batteries: Current States and Prospects
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作者 Bo Yang Yucun Qian +2 位作者 Jianzhong Xu Yaxing Ren Yixuan Chen 《Energy Engineering》 EI 2024年第8期2085-2091,共7页
1 Introduction.With the continuous growth of the global population,the energy demand continues to increase.However,due to the dominance of fossil fuels in global energy and fossil fuels are non-renewable,it has led to... 1 Introduction.With the continuous growth of the global population,the energy demand continues to increase.However,due to the dominance of fossil fuels in global energy and fossil fuels are non-renewable,it has led to the global energy crisis[1].Besides,the use of fossil fuels will generate a mass of air pollutants(e.g.,carbon dioxide,sulfur dioxide,etc.),which will cause serious environmental pollution,climate change[2],etc.To resolve the aforementioned issues,countries around the world have implemented a variety of measures hoping to fundamentally adjust the global energy structure and achieve sustainable development.Thereinto,“Paris Agreement”reached in 2015 under the framework of“United Nations Framework Convention on Climate Change”aims to control the increase in the average temperature of the globe to within 2°C below preindustrial levels,and thereafter to peak global greenhouse gas emissions as soon as possible,continuously decreasing thereafter[3].United Kingdom plans to reduce the average exhaust emissions of“new cars”to approximately 50–70 g/km by 20230,which is roughly half of what it is now[4].In addition,China proposed a plan at“United Nations General Assembly”in 2020 to peak carbon dioxide emissions by 2030 and strive to achieve carbon neutrality by 2060.It is a fact that the whole world is committed to changing the current energy structure,protecting the Earth’s ecology,and achieving global sustainable development[5]. 展开更多
关键词 Lithium batteries optimization operation MODELLING state estimation life prediction fault diagnosis
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Analyzing environmental flow supply in the semi-arid area through integrating drought analysis and optimal operation of reservoir
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作者 Mahdi SEDIGHKIA Bithin DATTA 《Journal of Arid Land》 SCIE CSCD 2023年第12期1439-1454,共16页
This study proposes a novel form of environmental reservoir operation through integrating environmental flow supply,drought analysis,and evolutionary optimization.This study demonstrates that simultaneous supply of do... This study proposes a novel form of environmental reservoir operation through integrating environmental flow supply,drought analysis,and evolutionary optimization.This study demonstrates that simultaneous supply of downstream environmental flow of reservoir as well as water demand is challenging in the semi-arid area especially in dry years.In this study,water supply and environmental flow supply were 40%and 30%in the droughts,respectively.Moreover,mean errors of supplying water demand as well as environmental flow in dry years were 6 and 9 m3/s,respectively.Hence,these results highlight that ecological stresses of the downstream aquatic habitats as well as water supply loss are considerably escalated in dry years,which implies even using environmental optimal operation is not able to protect downstream aquatic habitats properly in the severe droughts.Moreover,available storage in reservoir will be remarkably reduced(averagely more than 30×106 m3 compared with optimal storage equal to 70×106 m3),which implies strategic storage of reservoir might be threatened.Among used evolutionary algorithms,particle swarm optimization(PSO)was selected as the best algorithm for solving the novel proposed objective function.The significance of this study is to propose a novel objective function to optimize reservoir operation in which environmental flow supply is directly addressed and integrated with drought analysis.This novel form of optimization system can overcome uncertainties of the conventional objective function due to considering environmental flow in the objective function as well as drought analysis in the context of reservoir operation especially applicable in semi-arid areas.The results indicate that using either other water resources for water supply or reducing water demand is the only solution for managing downstream ecological impacts of the river ecosystem.In other words,the results highlighted that replanning of water resources in the study area is necessary.Replacing the conventional optimization system for reservoir operation in the semi-arid area with proposed optimization system is recommendable to minimize the negotiations between stakeholders and environmental managers. 展开更多
关键词 optimization reservoir operation DROUGHTS metaheuristic algorithms environmental flow regime
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Interpretable machine learning optimization(InterOpt)for operational parameters:A case study of highly-efficient shale gas development
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作者 Yun-Tian Chen Dong-Xiao Zhang +1 位作者 Qun Zhao De-Xun Liu 《Petroleum Science》 SCIE EI CAS CSCD 2023年第3期1788-1805,共18页
An algorithm named InterOpt for optimizing operational parameters is proposed based on interpretable machine learning,and is demonstrated via optimization of shale gas development.InterOpt consists of three parts:a ne... An algorithm named InterOpt for optimizing operational parameters is proposed based on interpretable machine learning,and is demonstrated via optimization of shale gas development.InterOpt consists of three parts:a neural network is used to construct an emulator of the actual drilling and hydraulic fracturing process in the vector space(i.e.,virtual environment);:the Sharpley value method in inter-pretable machine learning is applied to analyzing the impact of geological and operational parameters in each well(i.e.,single well feature impact analysis):and ensemble randomized maximum likelihood(EnRML)is conducted to optimize the operational parameters to comprehensively improve the efficiency of shale gas development and reduce the average cost.In the experiment,InterOpt provides different drilling and fracturing plans for each well according to its specific geological conditions,and finally achieves an average cost reduction of 9.7%for a case study with 104 wells. 展开更多
关键词 Interpretable machine learning operational parameters optimization Shapley value Shale gas development Neural network
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Chicken Swarm Optimization with Deep Learning Based Packaged Rooftop Units Fault Diagnosis Model
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作者 G.Anitha N.Supriya +3 位作者 Fayadh Alenezi E.Laxmi Lydia Gyanendra Prasad Joshi Jinsang You 《Computer Systems Science & Engineering》 SCIE EI 2023年第10期221-238,共18页
Rooftop units(RTUs)were commonly employed in small commercial buildings that represent that can frequently do not take the higher level maintenance that chillers receive.Fault detection and diagnosis(FDD)tools can be ... Rooftop units(RTUs)were commonly employed in small commercial buildings that represent that can frequently do not take the higher level maintenance that chillers receive.Fault detection and diagnosis(FDD)tools can be employed for RTU methods to ensure essential faults are addressed promptly.In this aspect,this article presents an Optimal Deep Belief Network based Fault Detection and Classification on Packaged Rooftop Units(ODBNFDC-PRTU)model.The ODBNFDC-PRTU technique considers fault diagnosis as amulti-class classification problem and is handled usingDL models.For fault diagnosis in RTUs,the ODBNFDC-PRTU model exploits the deep belief network(DBN)classification model,which identifies seven distinct types of faults.At the same time,the chicken swarm optimization(CSO)algorithm-based hyperparameter tuning technique is utilized for resolving the trial and error hyperparameter selection process,showing the novelty of the work.To illustrate the enhanced performance of the ODBNFDC-PRTU algorithm,a comprehensive set of simulations are applied.The comparison study described the improvement of the ODBNFDC-PRTU method over other recent FDD algorithms with maximum accuracy of 99.30%and TPR of 93.09%. 展开更多
关键词 Rooftop units chicken swarm optimization hyperparameter metaheuristics deep learning fault diagnosis
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Design and Operation of Municipal Rain and Sewage United Pumping Station
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作者 Ting Ting Liu 《Journal of Architectural Research and Development》 2023年第4期51-56,共6页
In the process of designing a municipal rainwater and sewage pumping station,it is necessary to accurately grasp the design points,reasonably determine the scale of the rainwater and sewage pumping station,scientifica... In the process of designing a municipal rainwater and sewage pumping station,it is necessary to accurately grasp the design points,reasonably determine the scale of the rainwater and sewage pumping station,scientifically select the location and layout,and select materials reasonably.After completing the process design of the municipal rainwater and sewage pumping station and putting it into operation,in order to ensure the normal and stable operation of the pumping station,it is necessary to focus on strengthening the operation and management of diving equipment,cleaning equipment,and electromechanical equipment.The author analyzes the key points and specific design path of the process design of municipal rainwater and sewage pumping stations,and puts forward effective strategies for operation management,hoping to contribute to the scientific design and stable operation of municipal rainwater and sewage pumping stations. 展开更多
关键词 Municipal administration Rainwater and sewage united pumping stations Design path operation management
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Operation optimization of the steel manufacturing process: A brief review 被引量:7
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作者 Zhao-jun Xu Zhong Zheng Xiao-qiang Gao 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2021年第8期1274-1287,共14页
Against the realistic background of excess production capacity, product structure imbalance, and high material and energy consumption in steel enterprises, the implementation of operation optimization for the steel ma... Against the realistic background of excess production capacity, product structure imbalance, and high material and energy consumption in steel enterprises, the implementation of operation optimization for the steel manufacturing process is essential to reduce the production cost, increase the production or energy efficiency, and improve production management. In this study, the operation optimization problem of the steel manufacturing process, which needed to go through a complex production organization from customers' orders to workshop production, was analyzed. The existing research on the operation optimization techniques, including process simulation, production planning, production scheduling, interface scheduling, and scheduling of auxiliary equipment, was reviewed. The literature review reveals that, although considerable research has been conducted to optimize the operation of steel production, these techniques are usually independent and unsystematic.Therefore, the future work related to operation optimization of the steel manufacturing process based on the integration of multi technologies and the intersection of multi disciplines were summarized. 展开更多
关键词 intelligent manufacturing operation optimization steel manufacturing process process simulation production planning production scheduling
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Operation and Optimization of Residue Hydrotreating Unit Using New Catalyst System 被引量:3
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作者 Yin Zhaolin 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2012年第3期50-58,共9页
This article has summarized the optimized measures relating to the loading of catalyst,and the sixth operating cycle of the residue hydrotreating unit at SINOPEC's Maoming Branch Company,and made a detailed compar... This article has summarized the optimized measures relating to the loading of catalyst,and the sixth operating cycle of the residue hydrotreating unit at SINOPEC's Maoming Branch Company,and made a detailed comparison on the impurities removal rate,hydrogen consumption and energy consumption of the sixth operating cycle with those achieved by the previous five cycles.Test results have revealed that the second-generation RHT series novel residue hydrotreating catalysts featured high activity,good stability,and long operating cycle and could remarkably reduce the hydrogen consumption and energy consumption of process unit.The hydrotreated AR product,having low Conradson carbon residue,low sulfur content,low metal content,high content of saturated hydrocarbons,and low content of asphaltenes and resins,is an excellent FCC feed.Judging from their overall property the second-generation RHT series of residue hydrotreating catalysts used in the sixth operating cycle have commanded a leading position among other catalysts used in previous operating cycles. 展开更多
关键词 加氢处理装置 催化剂体系 渣油加氢 操作系统 优化 加氢处理催化剂 能源消耗 单元
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A Novel Close-loop Strategy for Integrating Process Operations of Fluidized Catalytic Cracking Unit with Production Planning Optimization 被引量:4
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作者 王如强 李初福 +1 位作者 何小荣 陈丙珍 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第6期909-915,共7页
普通当模特儿的系统产生的生产计划模型不为进程操作包含限制,并且一个解决方案由这些模型优化被称为一个伪最佳的计划。伪最佳的计划不能为没有相应操作条件某时在实践被执行。以便决定一个实际上可行的最佳的计划和联合起来的使流体... 普通当模特儿的系统产生的生产计划模型不为进程操作包含限制,并且一个解决方案由这些模型优化被称为一个伪最佳的计划。伪最佳的计划不能为没有相应操作条件某时在实践被执行。以便决定一个实际上可行的最佳的计划和联合起来的使流体化的催化裂开的相应操作条件(FCCU ) ,新奇靠近环的综合策略包括一个伪最佳的计划的决心,操作 FCCU 的条件和计划模型的生产的修订寻找,在这篇文章被建议。在策略,一个概括基因算法(GA ) 结合了 FCCU 的一个顺序的过程模拟器被使用寻找实现 FCCU 的伪最佳的计划的操作条件并且作为一个最后的基因个人在 GA 搜索输出最佳的个人。当没有相应操作条件被发现时,最后的基因个人基于修正(FGIC ) 方法被介绍修订计划模型的生产,然后一个新伪最佳的生产计划是坚定的。上述步被重复直到一个实际上可行的最佳的计划和 FCCU 的相应操作条件被获得。靠近环的综合策略被二个盒子验证,并且策略在决定一个实际上执行的最佳的计划和 FCCU 的相应操作条件是有效的,这被显示。 展开更多
关键词 生产计划 催化裂化装置 过程操作 集成 闭环策略
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The Effects of SO_3 in Flue Gas on the Operation of Coalfired Units and Countermeasures
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作者 Hu Yufeng Xue Jianming 《Meteorological and Environmental Research》 CAS 2017年第5期120-124,共5页
There exists a certain amount of SO_3 in flue gas discharged from coal-fired power plants. With the operation of the selective catalystic reduction( SCR) denitrification system,SO_3 concentration in the flue gas incre... There exists a certain amount of SO_3 in flue gas discharged from coal-fired power plants. With the operation of the selective catalystic reduction( SCR) denitrification system,SO_3 concentration in the flue gas increases,which will lead to fouling,erosion and plugging of downstream equipment. In this study,the main effects of SO_3 on the safety,stability and efficiency of units were analyzed,and measures to control SO_3 were proposed. 展开更多
关键词 Coal-fired FLUE GAS S03 operation of unitS Control of S03
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The Optimization on Operation Characteristicsof Urban Medium Voltage Network
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作者 Yao Huannian Cao Meiyue(Xiamen Electric Power Administration, Xiamen) 《Electricity》 1998年第3期27-29,共3页
Traditional small current grounding system has many advantages. Pilot operation shows that optimized one has even better operation characteristics. It has proven to be a geenrallly properand relatively perfect neutyal... Traditional small current grounding system has many advantages. Pilot operation shows that optimized one has even better operation characteristics. It has proven to be a geenrallly properand relatively perfect neutyal grounding method in urban MV network. 展开更多
关键词 URBAN medium voltage NETWORK optimization operation characteristic small CURRENT GROUNDING SYSTEM large CURRENT GROUNDING SYSTEM
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Operation Experience of the First Supercritical Pressure Unit and Its Developmental Prospect
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《Electricity》 1997年第4期15-17,共3页
关键词 operation Experience of the First Supercritical Pressure unit and Its Developmental Prospect
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Using the curve moment and the PSO-SVM method to diagnose downhole conditions of a sucker rod pumping unit 被引量:24
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作者 Li Kun Gao Xianwen +1 位作者 Tian Zhongda Qiu Zhixue 《Petroleum Science》 SCIE CAS CSCD 2013年第1期73-80,共8页
Downhole working conditions of sucker rod pumping wells are automatically identified on a computer from the analysis of dynamometer cards. In this process, extraction of feature parameters and pattern classification a... Downhole working conditions of sucker rod pumping wells are automatically identified on a computer from the analysis of dynamometer cards. In this process, extraction of feature parameters and pattern classification are two key steps. The dynamometer card is firstly divided into four parts which include different production information according to the "four point method" used in actual oilfield production, and then the moment invariants for pattern recognition are extracted. An improved support vector machine (SVM) method is used for pattern classification whose error penalty parameter C and kernel function parameter g are optimally chosen by the particle swarm optimization (PSO) algorithm. The simulation results show the method proposed in this paper has good classification results. 展开更多
关键词 Sucker rod pumping unit diagnosis of downhole conditions dynamometer card curvemoment support vector machine particle swarm optimization
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Three-dimensional physical simulation and optimization of water injection of a multi-well fractured-vuggy unit 被引量:6
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作者 Ji-Rui HOU Ze-Yu Zheng +4 位作者 Zhao-Jie Song Min LUO Hai-Bo Li Li Zhang Deng-Yu Yuan 《Petroleum Science》 SCIE CAS CSCD 2016年第2期259-271,共13页
With complex fractured-vuggy heterogeneous structures, water has to be injected to facilitate oil pro- duction. However, the effect of different water injection modes on oil recovery varies. The limitation of existing... With complex fractured-vuggy heterogeneous structures, water has to be injected to facilitate oil pro- duction. However, the effect of different water injection modes on oil recovery varies. The limitation of existing numerical simulation methods in representing fractured- vuggy carbonate reservoirs makes numerical simulation difficult to characterize the fluid flow in these reservoirs. In this paper, based on a geological example unit in the Tahe Oilfield, a three-dimensional physical model was designed and constructed to simulate fluid flow in a fractured-vuggy reservoir according to similarity criteria. The model was validated by simulating a bottom water drive reservoir, and then subsequent water injection modes were optimized. These were continuous (constant rate), intermittent, and pulsed injection of water. Experimental results reveal that due to the unbalanced formation pressure caused by pulsed water injection, the swept volume was expanded and consequently the highest oil recovery increment was achieved. Similar to continuous water injection, intermit- tent injection was influenced by factors including the connectivity of the fractured-vuggy reservoir, well depth, and the injection-production relationship, which led to a relative low oil recovery. This study may provide a constructive guide to field production and for the devel- opment of the commercial numerical models specialized for fractured-vuggy carbonate reservoirs. 展开更多
关键词 Multi-well fractured-vuggy unit Three-dimensional physical model Similarity criteria Bottom water drive. optimization of water injection mode
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Operation optimization of plugged screen cleanup by rotary water jetting 被引量:3
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作者 Dong Changyin Li Yanlong +3 位作者 Long Jiajia Zhang Qinghua Wang Dengqing Wu Jianping 《Petroleum Science》 SCIE CAS CSCD 2014年第1期122-130,共9页
The rotary water jetting is one of the most important techniques for horizontal well cleanup.The jet flow is used to remove plugging particles from sand control screens to recover their permeability.Currently,the oper... The rotary water jetting is one of the most important techniques for horizontal well cleanup.The jet flow is used to remove plugging particles from sand control screens to recover their permeability.Currently,the operation optimization of this technique depends mainly on experience due to absence of applicable evaluation and design models for removing plugging materials.This paper presents an experimental setup to simulate the cleanup process of plugged screens by rotary water jetting on the surface and to evaluate the performance of a jetting tool.Using real plugged screens pulled from damaged wells,a series of tests were performed,and the qualitative relationships between the cleanup efficiency and various operational parameters,such as the type of fluids used,flow rate,mode of tool movement,etc.,were obtained.The test results indicated that the cleanup performance was much better when the rotary jetting tool moved and stopped periodically for a certain time than that when it reciprocated at a constant speed.To be exact,it was desirable for the rotary jetting tool to move for 1.5-2 m and stop for 2-4 min,which was called the "move-stop-move" mode.Good cleanup performance could be obtained at high flow rates,and the flow rate was recommended to be no lower than 550-600 L/min.The test results also indicated that complex mud acid was better than clean water in terms of cleanup performance.Good cleanup efficiency and high screen permeability recovery could be achieved for severely plugged screens.Rotary jetting is preferred for the cleanup of horizontal wells with severely plugged screens,and the screen permeability recovery ratio may reach 20% if optimized operation parameters were used. 展开更多
关键词 Sand control screen cleanup performance rotary jetting operation optimization experimental simulation
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A NEW OPTIMIZATION ALGORITHM BASED ON THE PRINCIPLE OF EVOLUTION 被引量:2
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作者 Yan Wei Zhu Zhaoda(Nanjing University of Aeronautics and Astronautics, Nanjing 210016) 《Journal of Electronics(China)》 1998年第3期248-253,共6页
A new genetic algorithm is proposed for the optimization problem of real-valued variable functions. A new robust and adaptive fitness scaling is presented by introducing the median of the population in exponential tra... A new genetic algorithm is proposed for the optimization problem of real-valued variable functions. A new robust and adaptive fitness scaling is presented by introducing the median of the population in exponential transformation. For float-point represented chromosomes, crossover and mutation operators are given. Convergence of the algorithm is proved. The performance is tested by two generally used functions. Hybrid algorithm which takes the BP algorithm as a mutation operator is used to train a neural network for image recognition. Experimental results show that the proposed algorithm is an efficient global optimization algorithm. 展开更多
关键词 GENETIC algorithm CROSSOVER and MUTATION OPERATORS Global optimization
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Optimization of the seismic processing phase-shift plus finite-difference migration operator based on a hybrid genetic and simulated annealing algorithm 被引量:2
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作者 Luo Renze Huang Yuanyi +2 位作者 Liang Xianghao Luo Jun Cao Ying 《Petroleum Science》 SCIE CAS CSCD 2013年第2期190-194,共5页
Although the phase-shift seismic processing method has characteristics of high accuracy, good stability, high efficiency, and high-dip imaging, it is not able to adapt to strong lateral velocity variation. To overcome... Although the phase-shift seismic processing method has characteristics of high accuracy, good stability, high efficiency, and high-dip imaging, it is not able to adapt to strong lateral velocity variation. To overcome this defect, a finite-difference method in the frequency-space domain is introduced in the migration process, because it can adapt to strong lateral velocity variation and the coefficient is optimized by a hybrid genetic and simulated annealing algorithm. The two measures improve the precision of the approximation dispersion equation. Thus, the imaging effect is improved for areas of high-dip structure and strong lateral velocity variation. The migration imaging of a 2-D SEG/EAGE salt dome model proves that a better imaging effect in these areas is achieved by optimized phase-shift migration operator plus a finite-difference method based on a hybrid genetic and simulated annealing algorithm. The method proposed in this paper is better than conventional methods in imaging of areas of high-dip angle and strong lateral velocity variation. 展开更多
关键词 Migration operator phase-shift plus finite-difference hybrid algorithm genetic andsimulated annealing algorithm optimization coefficient
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