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塑料注塑机五点斜排双曲肘合模系统特性研究 被引量:2
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作者 陈学锋 徐言生 +2 位作者 胡建国 许中明 殷小春 《中国塑料》 CSCD 北大核心 2015年第4期111-119,共9页
推导出高速精密塑料成型机双曲肘合模机构弹性动力学模型,利用实振型叠加法进行弹性动力分析(KED)/准静态分析(KES);实测肘杆振动加速度信号,通过最小二乘法(LMS)消除趋势项、平滑处理和二次频域积分得到振动位移值,并与理论模型值作对... 推导出高速精密塑料成型机双曲肘合模机构弹性动力学模型,利用实振型叠加法进行弹性动力分析(KED)/准静态分析(KES);实测肘杆振动加速度信号,通过最小二乘法(LMS)消除趋势项、平滑处理和二次频域积分得到振动位移值,并与理论模型值作对比研究,证明了所建模型的合理性,为肘杆机构的优化设计提供了依据。 展开更多
关键词 注塑机 双曲肘合模系统 实振型叠加法 振动 频域
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基于MATLAB的注塑机五支铰斜排双曲肘合模系统优化设计 被引量:3
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作者 石绍伟 杜思莹 +1 位作者 杜遥雪 徐百平 《五邑大学学报(自然科学版)》 CAS 2014年第4期55-61,共7页
对80T注塑机五支铰斜排双曲肘合模机构的运动特性和力学特性进行分析,确立以行程比和合模油缸推力放大倍数为优化目标,建立合模机构优化数学模型,确定参数化设计流程,并根据几何关系设立合理的约束参数,用MATLAB软件对合模机构进行优化... 对80T注塑机五支铰斜排双曲肘合模机构的运动特性和力学特性进行分析,确立以行程比和合模油缸推力放大倍数为优化目标,建立合模机构优化数学模型,确定参数化设计流程,并根据几何关系设立合理的约束参数,用MATLAB软件对合模机构进行优化设计.优化后,该机构行程比提高了31.91%,合模油缸推力放大倍数提高了0.46%,为降低五点斜排双曲肘合模机构的能耗,提高工作效率及注塑件的质量提供理论依据. 展开更多
关键词 注塑机 合模系统 MATLAB 优化设计
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注塑机双曲肘合模系统优化设计的研究 被引量:7
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作者 郭策 陈金元 《机械科学与技术》 EI CSCD 北大核心 1999年第5期757-760,共4页
结合中型注塑机对双曲肘合模系统优化设计进行了研究,指出中型机以功效系数最大建立的优化数模属非凸函数,非凸集,具有多解性。所取得的满意解明显优于现行设计。文中还讨论了设计变量与目标函数间的关系,并进行设计变量的灵敏度分... 结合中型注塑机对双曲肘合模系统优化设计进行了研究,指出中型机以功效系数最大建立的优化数模属非凸函数,非凸集,具有多解性。所取得的满意解明显优于现行设计。文中还讨论了设计变量与目标函数间的关系,并进行设计变量的灵敏度分析,为实际工程设计的方案选择、公差合理制定提供了依据。 展开更多
关键词 优化设计 注塑机 机构 双曲肘合模系统
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基于ADAMS的微结构注塑机合模系统的仿真分析
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作者 李世龙 张亚军 +2 位作者 金志明 董力群 庄俭 《塑料》 CAS CSCD 北大核心 2016年第6期73-75,共3页
为了提升微结构注塑机的成型精度,提高合模系统的合模力稳定性和运动特性尤为重要。文章设计了由伺服电机驱动的1300 k N微结构注塑机的合模系统。在此基础上,建立了该系统的三维几何模型,并在Adams虚拟样机环境中对开合模过程进行了多... 为了提升微结构注塑机的成型精度,提高合模系统的合模力稳定性和运动特性尤为重要。文章设计了由伺服电机驱动的1300 k N微结构注塑机的合模系统。在此基础上,建立了该系统的三维几何模型,并在Adams虚拟样机环境中对开合模过程进行了多体系统动力学及运动学仿真。仿真结果表明,在移模速度600 mm/s时,合模系统的开合模运动保持相对平稳。这对于保证制品质量和提高成型加工效率具有重要意义。此研究为提高微结构注塑机合模系统的设计精度和成型质量提供了理论依据。 展开更多
关键词 合模系统 成型精度 伺服电机 ADAMS 运动学仿真
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布勒两板压铸机合模系统介绍 被引量:2
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作者 卢宏远 邹智厚 +2 位作者 卢敏 赵晓栋 宋清 《特种铸造及有色合金》 CAS CSCD 北大核心 2011年第4期331-334,396,共4页
两板压铸机和三板压铸机的区别主要在于合模系统。两板压铸机的合模系统去除了三板压铸机中的后座板,只含有动模板和定模板。同时,在4根大杠尾端增加了随动锁紧机构取代了曲肘机构。两板合模系统主要由动模板、定模板、大杠、随动锁紧... 两板压铸机和三板压铸机的区别主要在于合模系统。两板压铸机的合模系统去除了三板压铸机中的后座板,只含有动模板和定模板。同时,在4根大杠尾端增加了随动锁紧机构取代了曲肘机构。两板合模系统主要由动模板、定模板、大杠、随动锁紧机构及合模缸组成。4根大杠仍然作为动、定模的连接及锁紧构件,但长度缩短,并在尾端增加了夹持齿槽。随动锁紧机构中包括对开螺母和锁紧油缸。对开螺母能够打开和闭合,闭合时与大杠上的夹持齿槽啮合,打开时解除啮合。锁紧缸是一个薄型液压室,用于拉伸大杠锁紧模具。开合模缸位于动模板后端,完成开合模动作。 展开更多
关键词 两板压铸机 合模系统 锁紧机构
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用于风电叶片制造的翻转合模系统 被引量:1
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作者 马瑞 《内燃机与配件》 2017年第5期40-43,共4页
本文主要介绍用于风电叶片制作的铰链模液压翻转系统概况、项目来源、国内外技术现状、我公司产品的技术方案和优点。
关键词 叶片 铰链翻转合模系统 同步系统
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基于单神经元自适应PID控制的注塑机合模机构 被引量:2
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作者 罗亮 李江源 刘知贵 《中国塑料》 CAS CSCD 北大核心 2015年第11期108-112,共5页
设计了一个单神经元自适应比例-积分-微分控制器(PID)控制器,使用AMESim/Simulink联合仿真机制,建立了注塑机合模机构液压伺服系统的模型。由仿真结果看,与常规PID控制器相比,使用单神经元自适应PID控制器控制的系统有着更好的鲁棒性,... 设计了一个单神经元自适应比例-积分-微分控制器(PID)控制器,使用AMESim/Simulink联合仿真机制,建立了注塑机合模机构液压伺服系统的模型。由仿真结果看,与常规PID控制器相比,使用单神经元自适应PID控制器控制的系统有着更好的鲁棒性,系统获得了更好的环境适应性。 展开更多
关键词 注塑机 合模系统 单神经元自适应 比例-积分-微分控制器
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大型塑件注射模结构设计中的几个要点 被引量:1
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作者 花杏华 《模具制造》 2004年第4期37-38,共2页
关键词 注射 结构设计 浇注系统 导向系统 注塑
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Risk prediction models for post-intensive care syndrome of ICU discharged patients:A systematic review
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作者 Pengfei Yang Fu Yang +3 位作者 Qi Wang Fang Fang Qian Yu Rui Tai 《International Journal of Nursing Sciences》 2025年第1期81-88,I0004,共9页
Objectives:This systematic review aimed to assess the properties and feasibility of existing risk prediction models for post-intensive care syndrome outcomes in adult survivors of critical illness.Methods:As of Novemb... Objectives:This systematic review aimed to assess the properties and feasibility of existing risk prediction models for post-intensive care syndrome outcomes in adult survivors of critical illness.Methods:As of November 1,2023,Cochrane Library,PubMed,Embase,CINAHL,Web of Science,PsycInfo,China National Knowledge Infrastructure(CNKI),SinoMed,Wanfang database,and China Science and Technology Journal Database(VIP)were searched.Following the literature screening process,we extracted data encompassing participant sources,post-intensive care syndrome(PICS)outcomes,sample sizes,missing data,predictive factors,model development methodologies,and metrics for model performance and evaluation.We conducted a review and classification of the PICS domains and predictive factors identified in each study.The Prediction Model Risk of Bias Assessment Tool was employed to assess the quality and applicability of the studies.Results:This systematic review included a total of 16 studies,comprising two cognitive impairment studies,four psychological impairment studies,eight physiological impairment studies,and two studies on all three domains.The discriminative ability of prediction models measured by area under the receiver operating characteristic curve was 0.68e0.90.The predictive performance of most models was excellent,but most models were biased and overfitted.All predictive factors tend to encompass age,pre-ICU functional impairment,in-ICU experiences,and early-onset new symptoms.Conclusions:This review identified 16 prediction models and the predictive factors for PICS.Nonetheless,due to the numerous methodological and reporting shortcomings identified in the studies under review,clinicians should exercise caution when interpreting the predictions made by these models.To avert the development of PICS,it is imperative for clinicians to closely monitor prognostic factors,including the in-ICU experience and early-onset new symptoms. 展开更多
关键词 Critical care Post-intensive care syndrome Prediction model Systematic review
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Higher-order mode analysis for SOLEIL-type superconducting cavity
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作者 Xiyuan Chai Qin Li +3 位作者 Yunpeng Xu Yungai Tang Mingsheng Tan Cong-Feng Wu 《中国科学技术大学学报》 CAS CSCD 北大核心 2024年第7期56-65,55,I0003,共12页
A 499.8 MHz SOLEIL-type superconducting cavity was simulated and designed for the first time in this paper.The higher-order mode(HOM)properties of the cavity were investigated.Two kinds of coaxial HOM couplers were de... A 499.8 MHz SOLEIL-type superconducting cavity was simulated and designed for the first time in this paper.The higher-order mode(HOM)properties of the cavity were investigated.Two kinds of coaxial HOM couplers were designed.Using 4 L-type and 4 T-type HOM couplers,the longitudinal impedance and the transverse impedances were suppressed to below 3 kΩand 30 kΩ/m,respectivly.The HOM damping requirements of Hefei Advanced Light Facility(HALF)were satisfied.This paper conducted an in-depth study on the radio frequency(RF)design,multipacting optimization,and thermal analysis of these coaxial couplers.Simulation results indicated that under operating acceleration voltage,the optimized couplers does not exhibit multiplicating or thermal breakdown phenomena.The cavity has the potential to reach a higher acceleration gradient. 展开更多
关键词 HOM coupler superconducting cavity RF system multipacting thermal simulation
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微注塑成型机的研究现状与进展 被引量:9
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作者 庄俭 张建国 +2 位作者 高世权 吴大鸣 张亚军 《塑料科技》 CAS 北大核心 2009年第5期92-95,共4页
在阐述了微注塑成型技术特点及定义的基础上,提出了微注塑成型技术对成型机的特殊要求,介绍并分析了微注塑成型机的市场现状。根据结构特点,对微注塑成型机进行分类,并对其技术参数做出说明,同时,展望了微注塑成型机的发展趋势。
关键词 微注塑成型 微型塑件 注射系统 塑化单元 合模系统
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电动压铸机合模机构的优化设计 被引量:4
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作者 宫杨杨 张亚军 +2 位作者 庄俭 杨于光 金志明 《特种铸造及有色合金》 CAS CSCD 北大核心 2017年第5期498-500,共3页
根据电动5支点斜排肘杆式压铸机的特点与要求,建立了合模机构的数学模型。使用正态分布的概率累积函数构建优化目标函数,设定主要性能参数的期望值与波动量,设置优化的约束条件,按照有约束非线性最优化的求解方法对合模机构进行系统性... 根据电动5支点斜排肘杆式压铸机的特点与要求,建立了合模机构的数学模型。使用正态分布的概率累积函数构建优化目标函数,设定主要性能参数的期望值与波动量,设置优化的约束条件,按照有约束非线性最优化的求解方法对合模机构进行系统性优化。分析表明,优化后机构力的放大比提高了约39.7%,达到24.3;行程比为1.06,较为理想;最大开模行程可达381.4mm,有所增大;运动曲线平缓、冲击小,整体性能更加适合电动压铸机。 展开更多
关键词 电动 合模系统 肘杆式 优化设计
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Modeling method of hybrid systems using extended Petrinets 被引量:1
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作者 周炳海 王世进 陶丽华 《Journal of Southeast University(English Edition)》 EI CAS 2005年第3期304-309,共6页
In order to model effectively hybrid systems,a new modeling method of extended Petri nets,which is called extended object-orient hybrid Petri net (EOHPN),is proposed.To deal with the complexity of hybrid systems, ob... In order to model effectively hybrid systems,a new modeling method of extended Petri nets,which is called extended object-orient hybrid Petri net (EOHPN),is proposed.To deal with the complexity of hybrid systems, object-oriented abstraction mechanisms such as encapsulation and classifications are merged into EOHPN models.To combine the continuous part and discrete part of hybrid systems and to reduce the complexity of hybrid systems,a hybrid Petri net is introduced and extended with object-oriented modeling technology.Development of object models is suggested on the basis of the defined EOHPN.Finally, an application-oriented case is presented to illustrate that how the proposed EOHPN is used to model hybrid systems.The resulting model validates that the EOHPNs can deal with the modeling complexity of hybrid systems. 展开更多
关键词 Petri nets object-oriented model hybrid system MODELING
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Criteria Selecting Knowledge Base in the FuzzyController of the Electrohydraulic Position Control System
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作者 高建臣 吴平东 《Journal of Beijing Institute of Technology》 EI CAS 1998年第1期84-91,共8页
Aim To analyse the influence of knowledge base on the performance of the fuzzy controller of the electrohydraulic position control system,and to determine their selection cri- teria. Methods Experiments based on diffe... Aim To analyse the influence of knowledge base on the performance of the fuzzy controller of the electrohydraulic position control system,and to determine their selection cri- teria. Methods Experiments based on different membership functions,scaling factors and con-trol rules were done separately.The experiment results and the influence of different know- ledge base on the control performance were analysed in theory so that criteria of selcting knowledge base can be summarized correctly.Results Knowledge base,including membershipfunctions, scaling factors and control rules,has a crucial effect on the fuzzy control system.Suitably selected knowledge base can lead to good control performance of fuzzy control sys-tem. Conclusion Being symmetric,having an intersection ratio of 1 and satisfying width con- dition are three necessities for selecting membership functions.Selecting scaling factors dependson both the system requirement and a comprehensive analysis in the overshoot,oscillation, rising time and stability. Integrity and continuity must be guaranteed when determining control rules. 展开更多
关键词 fuzzy control knowledge base position control systems fuzzy sets
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Model Compounds of the Mn Cluster in Oxygen-evolving Complex of PSⅡ
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作者 陈昌能 朱红平 +1 位作者 黄德光 刘秋田 《Acta Botanica Sinica》 CSCD 2000年第12期1249-1252,共4页
Six model compounds have been synthesized and used for probing the structural features of the Mn cluster in oxygen_evolving complex (OEC) of photosystem Ⅱ (PSⅡ). The model compounds contain Mn 2(μ_O) 2 and μ_O_... Six model compounds have been synthesized and used for probing the structural features of the Mn cluster in oxygen_evolving complex (OEC) of photosystem Ⅱ (PSⅡ). The model compounds contain Mn 2(μ_O) 2 and μ_O_μ_carboxylato di_manganese structural units, which offer Mn—Mn, Mn……Mn, and Mn—O(N) structural parameters consistent with the corresponding data of the OEC in PSⅡ, implying that the Mn cluster in OEC may possess similar structural features. Two model compounds containing halide anion have been used for discussing the binding of Cl - to Mn in PSⅡ. It is suggested that in the five S states, ligand exchange would lead to the ligation of chloride to Mn in the S states with Mn of higher valence. 展开更多
关键词 PHOTOSYSTEM oxygen-evolving complex model compound manganese cluster
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立式电动注塑机
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《橡塑技术与装备》 CAS 2003年第4期40-40,共1页
日本日精树脂工业株式会社推出TH和TD系列全电动立式注塑机,该系列机型是根据普通立式液压机的特点进行改进而得,用户可按用途选择单级式和转台式合模系统。
关键词 立式电动注塑机 日本日精树脂工业株式会社 立式液压机 单级式 转台式 合模系统
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Power System Simulation Laboratory of EPRI of China
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作者 曾昭华 蒋卫平 《Electricity》 2001年第4期25-29,共5页
The Power System Simulation Lab constructed specifically for the Three Gorges AC/DC hybrid transmissionstudy is equipped mainly with a real-time power system simulator, which can jointly operate with existing TNA andH... The Power System Simulation Lab constructed specifically for the Three Gorges AC/DC hybrid transmissionstudy is equipped mainly with a real-time power system simulator, which can jointly operate with existing TNA andHVDC Simulator respectively. Appraised by the State Power Corporation 3 years ago, this Lab was proved reachinginternational advanced level. Several large-scaled power system studies, such as the "Simplified Three Gorges PowerSystem Study" have achieved good results.[ 展开更多
关键词 power system hybrid real-time simulator
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Numerical Simulation of Typhoon Muifa(2011) Using a Coupled Ocean-Atmosphere-Wave-Sediment Transport(COAWST) Modeling System 被引量:12
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作者 LIU Na LING Tiejun +3 位作者 WANG Hui ZHANG Yunfei GAO Zhiyi WANG Yi 《Journal of Ocean University of China》 SCIE CAS 2015年第2期199-209,共11页
The newly developed Coupled Ocean-Atmosphere-Wave-Sediment Transport(COAWST) Modeling System is applied to investigate typhoon-ocean interactions in this study. The COAWST modeling system represents the state-of-the-a... The newly developed Coupled Ocean-Atmosphere-Wave-Sediment Transport(COAWST) Modeling System is applied to investigate typhoon-ocean interactions in this study. The COAWST modeling system represents the state-of-the-art numerical simulation technique comprising several coupled models to study coastal and environmental processes. The modeling system is applied to simulate Typhoon Muifa(2011), which strengthened from a tropical storm to a super typhoon in the Northwestern Pacific, to explore the heat fluxes exchanged among the processes simulated using the atmosphere model WRF, ocean model ROMS and wave model SWAN. These three models adopted the same horizontal grid. Three numerical experiments with different coupling configurations are performed in order to investigate the impact of typhoon-ocean interaction on the intensity and ocean response to typhoon. The simulated typhoon tracks and intensities agree with observations. Comparisons of the simulated variables with available atmospheric and oceanic observations show the good performance of using the coupled modeling system for simulating the ocean and atmosphere processes during a typhoon event. The fully coupled simulation that includes a ocean model identifies a decreased SST as a result of the typhoon-forced entrainment. Typhoon intensity and wind speed are reduced due to the decrease of the sea surface temperature when using a coupled ocean model. The experiments with ocean coupled to atmosphere also results in decreased sea surface heat flux and air temperature. The heat flux decreases by about 29% compared to the WRF only case. The reduction of the energy induced by SST decreases, resulting in weakening of the typhoon. Coupling of the waves to the atmosphere and ocean model induces a slight increase of SST in the typhoon center area with the ocean-atmosphere interaction increased as a result of wave feedback to atmosphere. 展开更多
关键词 COAWST modeling system typhoon Muifa WRF ROMS SWAN
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Stabilization of Networked Control Systems Using a Mixed-Mode Based Switched Delay System Method 被引量:3
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作者 Qing-Kui Li Xiaoli Li +1 位作者 Jiuhe Wang Shengli Du 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2018年第6期1089-1098,共10页
The phenomenon of mixed-mode is one of the most important characteristics of switched delay systems. If a networked control system(NCS) with network induced delays and packet dropouts(NIDs & PDs) is recast as a sw... The phenomenon of mixed-mode is one of the most important characteristics of switched delay systems. If a networked control system(NCS) with network induced delays and packet dropouts(NIDs & PDs) is recast as a switched delay system, it is imperative to consider the effects of mixed-modes in the stability analysis for an NCS. In this paper, with the help of the interpolatory quadrature formula and the average dwell time method, stabilization of NCSs using a mixed-mode based switched delay system method is investigated based on a novel constructed Lyapunov-Krasovskii functional. With the Finsler's lemma, new exponential stabilizability conditions with less conservativeness are given for the NCS. Finally, an illustrative example is provided to verify the effectiveness of the developed results. 展开更多
关键词 Interpolatory quadrature formula mixed-mode networked control system (NCS) switched delay system
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Optimization of Wind-Marine Hybrid Power System Configuration Based on Genetic Algorithm 被引量:1
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作者 SHI Hongda LI Linna ZHAO Chenyu 《Journal of Ocean University of China》 SCIE CAS CSCD 2017年第4期709-715,共7页
Multi-energy power systems can use energy generated from various sources to improve power generation reliability.This paper presents a cost-power generation model of a wind-tide-wave energy hybrid power system for use... Multi-energy power systems can use energy generated from various sources to improve power generation reliability.This paper presents a cost-power generation model of a wind-tide-wave energy hybrid power system for use on a remote island,where the configuration is optimized using a genetic algorithm.A mixed integer programming model is used and a novel object function,including cost and power generation,is proposed to solve the boundary problem caused by existence of two goals.Using this model,the final optimized result is found to have a good fit with local resources. 展开更多
关键词 genetic algorithm cost-power generation function multi-energy system marine energy
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