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Fortifying Smart Grids: A Holistic Assessment Strategy against Cyber Attacks and Physical Threats for Intelligent Electronic Devices
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作者 Yangrong Chen June Li +4 位作者 Yu Xia Ruiwen Zhang Lingling Li Xiaoyu Li Lin Ge 《Computers, Materials & Continua》 SCIE EI 2024年第8期2579-2609,共31页
Intelligent electronic devices(IEDs)are interconnected via communication networks and play pivotal roles in transmitting grid-related operational data and executing control instructions.In the context of the heightene... Intelligent electronic devices(IEDs)are interconnected via communication networks and play pivotal roles in transmitting grid-related operational data and executing control instructions.In the context of the heightened security challenges within smart grids,IEDs pose significant risks due to inherent hardware and software vulner-abilities,as well as the openness and vulnerability of communication protocols.Smart grid security,distinct from traditional internet security,mainly relies on monitoring network security events at the platform layer,lacking an effective assessment mechanism for IEDs.Hence,we incorporate considerations for both cyber-attacks and physical faults,presenting security assessment indicators and methods specifically tailored for IEDs.Initially,we outline the security monitoring technology for IEDs,considering the necessary data sources for their security assessment.Subsequently,we classify IEDs and establish a comprehensive security monitoring index system,incorporating factors such as running states,network traffic,and abnormal behaviors.This index system contains 18 indicators in 3 categories.Additionally,we elucidate quantitative methods for various indicators and propose a hybrid security assessment method known as GRCW-hybrid,combining grey relational analysis(GRA),analytic hierarchy process(AHP),and entropy weight method(EWM).According to the proposed assessment method,the security risk level of IEDs can be graded into 6 levels,namely 0,1,2,3,4,and 5.The higher the level,the greater the security risk.Finally,we assess and simulate 15 scenarios in 3 categories,which are based on monitoring indicators and real-world situations encountered by IEDs.The results show that calculated security risk level based on the proposed assessment method are consistent with actual simulation.Thus,the reasonableness and effectiveness of the proposed index system and assessment method are validated. 展开更多
关键词 Smart grid intelligent electronic device security assessment abnormal behaviors network traffic running states
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Modified DS np Chart Using Generalized Multiple Dependent State Sampling under Time Truncated Life Test
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作者 Wimonmas Bamrungsetthapong Pramote Charongrattanasakul 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2471-2495,共25页
This study presents the design of a modified attributed control chart based on a double sampling(DS)np chart applied in combination with generalized multiple dependent state(GMDS)sampling to monitor the mean life of t... This study presents the design of a modified attributed control chart based on a double sampling(DS)np chart applied in combination with generalized multiple dependent state(GMDS)sampling to monitor the mean life of the product based on the time truncated life test employing theWeibull distribution.The control chart developed supports the examination of the mean lifespan variation for a particular product in the process of manufacturing.Three control limit levels are used:the warning control limit,inner control limit,and outer control limit.Together,they enhance the capability for variation detection.A genetic algorithm can be used for optimization during the in-control process,whereby the optimal parameters can be established for the proposed control chart.The control chart performance is assessed using the average run length,while the influence of the model parameters upon the control chart solution is assessed via sensitivity analysis based on an orthogonal experimental design withmultiple linear regression.A comparative study was conducted based on the out-of-control average run length,in which the developed control chart offered greater sensitivity in the detection of process shifts while making use of smaller samples on average than is the case for existing control charts.Finally,to exhibit the utility of the developed control chart,this paper presents its application using simulated data with parameters drawn from the real set of data. 展开更多
关键词 Modified DS np chart generalizedmultiple dependent state sampling time truncated life test Weibull distribution average run length average sample size
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Running States of China's Iron & Steel,Nonferrous,and Building Materials Industries in 2012
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《China's Refractories》 CAS 2013年第1期11-11,共1页
Iron & Steel Industry China's outputs of crude steel, steel products, coke and ferrous alloys in 2012 were 716.54 million tons (up 3.1% YOY), 051.86 million tons (up 7.7% YOY), 443.23 million tons (up 5.2% YOY... Iron & Steel Industry China's outputs of crude steel, steel products, coke and ferrous alloys in 2012 were 716.54 million tons (up 3.1% YOY), 051.86 million tons (up 7.7% YOY), 443.23 million tons (up 5.2% YOY) and 31.29 million tons (up 15% YOY), 展开更多
关键词 running states of China’s Iron Steel Nonferrous and Building Materials Industries in 2012
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Running State of China's Building Materials Industry in 2013
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《China's Refractories》 CAS 2014年第1期42-42,共1页
In 2013, China's outputs of cement and flat glass were 2. 414 billion tons and 778.98 million weight cases, increasing by 9.6% and 11.2% YOY, respectively.
关键词 running state of China’s Building Materials Industry in 2013
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Problems and Countermeasures of Taihu Port Farm in Jingzhou City after Function Reform of Running the Society
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作者 Hefan XU Jun ZHENG Jiafeng YU 《Asian Agricultural Research》 2019年第8期1-4,共4页
Deepening function reform of running the society of state-owned farm is an important strategic plan made by the Party Central Committee and the State Council,and is also ' hard bone' bitten by fully implementi... Deepening function reform of running the society of state-owned farm is an important strategic plan made by the Party Central Committee and the State Council,and is also ' hard bone' bitten by fully implementing the strategy of rural revitalization and promoting the modernization of agriculture and countryside. In this paper,the problems of Taihu Port Farm in Jingzhou City after function reform of running the society are systematically and comprehensively analyzed via field research,and corresponding countermeasures are proposed. The research could provide beneficial reference and experience reference for deepening function reform of running the society of current state-owned farm. 展开更多
关键词 Function reform of running the SOCIETY of state-OWNED FARM Agricultural MODERNIZATIon Rural REVITALIZATIon Taihu PORT FARM
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基于双重约束的并网逆变器电流自动化控制方法研究
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作者 陈志刚 高冰 +1 位作者 李滨 杨晓磊 《自动化与仪表》 2024年第2期30-34,共5页
为降低并网逆变器逆变的并网电流畸变率,提出基于双重约束的并网逆变器电流自动化控制方法。以典型的三相LCL并网逆变器为例,分析其运行状态;并确定并网逆变器在进行逆变转换时,谐波对于逆变器并网电流的影响,计算并网逆变器环路增益函... 为降低并网逆变器逆变的并网电流畸变率,提出基于双重约束的并网逆变器电流自动化控制方法。以典型的三相LCL并网逆变器为例,分析其运行状态;并确定并网逆变器在进行逆变转换时,谐波对于逆变器并网电流的影响,计算并网逆变器环路增益函数;采用输出电流直接前馈的改进阻尼控制方法实现电流自动化控制,并引入全局-局部稳定双重约束原则,确定最佳的谐振抑制参数,提升电流的控制效果。测试结果显示,该方法的并网逆变器的电流畸变率均低于5%,电流跳变过程中,可在0.2 s内有效控制跳变电流结果。 展开更多
关键词 双重约束 并网逆变器 自动化控制 谐振抑制参数 增益函数 运行状态
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基于Mask R-CNN的电力关键设备运行状态检测
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作者 吕超 杨德宇 +1 位作者 刘文杰 张克胜 《电子设计工程》 2024年第2期107-110,115,共5页
为判断电力关键设备两端负载电压与干路总电压之间的数值关系,提出基于Mask R-CNN的电力关键设备运行状态检测方法。在Mask R-CNN网络结构中,判断电量信号的时域范围与频域范围。然后根据负荷阻抗特征计算交流参数的取值结果,再联合已... 为判断电力关键设备两端负载电压与干路总电压之间的数值关系,提出基于Mask R-CNN的电力关键设备运行状态检测方法。在Mask R-CNN网络结构中,判断电量信号的时域范围与频域范围。然后根据负荷阻抗特征计算交流参数的取值结果,再联合已获取的电信号参量,求解连续相关函数,从而检测电力关键设备运行状态。实验过程中,设备两端负载电压、内阻消耗电压之和与干路总电压之间的差值未超过1.5 V,说明该方法能够证明电力关键设备两端负载电压、内阻消耗电压之和等于干路总电压数值的猜想成立,可以根据该验证检测电力关键设备运行状态是否正常。 展开更多
关键词 Mask R-CNN模型 电力设备 运行状态 负荷阻抗 交流参数 负载电压
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抗战时期宜红茶复兴计划与国营体系的建立
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作者 李超 许胜男 《农业考古》 北大核心 2024年第2期33-41,共9页
晚清以来,在国际市场需求的带动和自身发展优势的基础上,宜红茶贸易兴起,区域茶业逐渐兴盛,并形成了“宜红茶”品牌。抗战时期,在国际国内局势和“中国茶业复兴计划”的影响下,“宜红复兴计划”被提出。中国茶叶公司、湖北省平价物品供... 晚清以来,在国际市场需求的带动和自身发展优势的基础上,宜红茶贸易兴起,区域茶业逐渐兴盛,并形成了“宜红茶”品牌。抗战时期,在国际国内局势和“中国茶业复兴计划”的影响下,“宜红复兴计划”被提出。中国茶叶公司、湖北省平价物品供应处茶叶部先后在宜红茶区投资设厂,推动了宜红茶区国营茶厂的建立与国营体系的发展,体现了传统商品经济在近代全球化趋势中的生存境遇与抉择,奠定了区域茶业社会经济的历史格局。 展开更多
关键词 宜红茶 国营茶厂 抗战时期
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基于转子铜耗的异步机运行状态分类
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作者 程小华 《防爆电机》 2024年第4期1-3,共3页
提出一个关于异步机运行状态的新的分类方法:转子铜耗法。按此法,异步机运行状态可分为两个:差能态、和能态。差能态包含电动、发电两个态;和能态对应电制态。转子铜耗分类法对学习和巩固异步机制动知识点尤其有帮助。
关键词 异步机 运行状态分类 转子铜耗 差能态 和能态 转差率 电制 电动 发电
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发电厂设备运行状态的在线数字孪生仿真系统 被引量:2
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作者 吴崛起 安凤栓 王全康 《自动化技术与应用》 2024年第1期148-152,共5页
为提升设备运行状态监测效果,设计发电厂设备运行状态的在线数字孪生仿真系统。构建发电厂环境及设备的三维模型,依据虚拟发电厂与发电厂实际布局建立设备数字孪生体,通过实时数据驱动虚拟发电厂,获取在线仿真预测的孪生数据,输入自组... 为提升设备运行状态监测效果,设计发电厂设备运行状态的在线数字孪生仿真系统。构建发电厂环境及设备的三维模型,依据虚拟发电厂与发电厂实际布局建立设备数字孪生体,通过实时数据驱动虚拟发电厂,获取在线仿真预测的孪生数据,输入自组织映射神经网络,输出设备运行状态监测结果,在线监测结果为发电厂管理提供辅助决策。仿真实验证明:该系统可有效采集设备相关信息冗余率低,可有效建立清晰的虚拟发电厂,实现设备运行状态在线监测;在不同天气情况下,该系统的微小故障发现率均较高,具备较优的在线监测效果。 展开更多
关键词 发电厂 设备运行状态 数字孪生 在线监测
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我国内地民族班(校)研究的回溯与展望
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作者 施娜 《西部学刊》 2024年第16期1-5,共5页
内地民族班(校)是向世界“讲好中国故事,传播好中国声音”的民族教育窗口,是促进各民族学生、师生和文化之间交往交流交融的重要教育渠道和中国特色解决问题方案。目前,我国内地民族班(校)研究势头良好,研究内容可按宏观国家意识形态、... 内地民族班(校)是向世界“讲好中国故事,传播好中国声音”的民族教育窗口,是促进各民族学生、师生和文化之间交往交流交融的重要教育渠道和中国特色解决问题方案。目前,我国内地民族班(校)研究势头良好,研究内容可按宏观国家意识形态、中观学校意识生态和微观个体意识心态的“意识三态观”分为三类;多采用跨学科、多学科视角研究,不同学科视角所采用的研究方法有所不同。未来,应加强宏观国家意识形态层面研究的时效性、中观学校意识生态层面的办学模式研究和微观个体意识心态层面的归因分析研究;同时,应科学规范研究方法的使用,编制跨文化适应的权威量表等。 展开更多
关键词 内地民族班(校) 办学实践 意识三态观
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国企举办高职院校政策的历史流变与未来展望
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作者 王浩 《山东高等教育》 2024年第3期75-81,92,共8页
国有企业举办高职院校政策经历了强制性、指令性、交织性、倡导性四个阶段。在这种政策流变情况下,学校的服务对象经历了“服务举办方国有企业”“服务举办方国有企业兼顾服务地方经济”和“服务地方经济兼顾服务举办方国有企业”三次... 国有企业举办高职院校政策经历了强制性、指令性、交织性、倡导性四个阶段。在这种政策流变情况下,学校的服务对象经历了“服务举办方国有企业”“服务举办方国有企业兼顾服务地方经济”和“服务地方经济兼顾服务举办方国有企业”三次转变过渡。目前,国企举办高职院校政策存在观照不够、过于宏观和冲突偏离三个缺陷,可以从“从相对无序向适当有序过渡”“从解决校企矛盾到促进校企共生发展”和“从宏观倡导向微观落地具化”三个方面调整。从单独出台扶持政策、多部门联合制定政策以及系统性出台政策等三个方面对国家政策进行了未来展望。 展开更多
关键词 国有企业 企业办学 高职院校 政策流变
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高压电气设备故障运行状态自适应预警方法
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作者 曹洋 《河南科技》 2024年第11期5-8,共4页
【目的】为了提前发现潜在的高压电气设备故障,并及时采取有效措施进行修复或维护,以确保高压电气设备的安全运行和延长高压电气设备的使用寿命,为此提出了高压电气设备故障运行状态自适应预警方法。【方法】建立高压电气设备故障运行... 【目的】为了提前发现潜在的高压电气设备故障,并及时采取有效措施进行修复或维护,以确保高压电气设备的安全运行和延长高压电气设备的使用寿命,为此提出了高压电气设备故障运行状态自适应预警方法。【方法】建立高压电气设备故障运行状态数据库,利用所收集、分析和处理的数据来建立高压电气设备运行状态模型,结合该模型实现高压电气设备故障运行状态自适应预警。【结果】试验结果表明,该方法的高压电气设备故障运行状态自适应预警效果较好,具备较高的实际应用价值。【结论】该设计能够监测高压电气设备运行状态,通过分析数据和模式识别,及时发现潜在的故障迹象,有助于预防设备的故障发生,避免大规模停机和生产中断,提高设备的安全性和可靠性。 展开更多
关键词 电气设备 故障运行状态 状态预警 预警方法 数据库 运行状态模型
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基于决策树的继电保护设备故障运行状态自动检测研究
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作者 吴园园 杨琼琼 《自动化应用》 2024年第11期227-228,231,共3页
针对配电系统继电保护设备终端负荷不断增容会导致设备故障发生概率不断加大的问题,提出基于决策树的继电保护设备故障运行状态自动检测方法。基于决策树算法构建故障自动诊断模型,利用网络训练分类器和回归预测器等机器学习算法,以提... 针对配电系统继电保护设备终端负荷不断增容会导致设备故障发生概率不断加大的问题,提出基于决策树的继电保护设备故障运行状态自动检测方法。基于决策树算法构建故障自动诊断模型,利用网络训练分类器和回归预测器等机器学习算法,以提高诊断效率和准确性,并自动检测继电保护设备的故障运行状态。结果表明,与传统方法相比,该方法能快速准确地识别故障位置,证明决策树算法在继电保护设备故障运行状态自动检测中具有较高的准确性。 展开更多
关键词 决策树算法 运行状态检测 故障检测 继电保护设备
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基于光纤通信的配电自动化终端电源运行状态监测方法
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作者 于国航 高续元 《通信电源技术》 2024年第16期130-133,共4页
配电自动化终端数据量庞大且电磁干扰严重,导致监测结果的实时性和准确性不佳。因此,提出基于光纤通信的配电自动化终端电源运行状态监测方法设计。该方法通过光纤通信技术将采集到的配电自动化终端电源运行数据实时传输到监测中心,然... 配电自动化终端数据量庞大且电磁干扰严重,导致监测结果的实时性和准确性不佳。因此,提出基于光纤通信的配电自动化终端电源运行状态监测方法设计。该方法通过光纤通信技术将采集到的配电自动化终端电源运行数据实时传输到监测中心,然后监测中心根据信息建立状态评价体系,实现配电自动化终端电源运行状态监测。仿真实验结果表明,该方法的监测结果能够准确反映实际值,且监测用时只需1.03min,证明该方法能够迅速获取终端电源的各项关键参数,精确监测配电自动化终端电源运行状态。 展开更多
关键词 光纤通信 配电自动化 终端电源 运行状态 监测方法
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Creatine supplementation in exercised rats: Effects on the aerobic capacity
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作者 Michel Barbosa de Araújo Roberto C. Vieira Junior +5 位作者 Leandro P. Moura Marcelo Costa Junior Rodrigo A. Dalia Amanda Christine da Silva Sponton Carla Ribeiro Maria Alice R. Mello 《Open Journal of Animal Sciences》 2013年第1期21-26,共6页
This study aimed to analyze the possible metabolic disturbances caused by creatine supplementation on aerobic capacity of rats, inferred by the maximal lactate steady state. Forty male Wistar rats (90 days old) were d... This study aimed to analyze the possible metabolic disturbances caused by creatine supplementation on aerobic capacity of rats, inferred by the maximal lactate steady state. Forty male Wistar rats (90 days old) were distributed into two groups for eight weeks: trained group (T): rats that were submitted to a training protocol, and supplemented-trained group (TCr): rats that were submitted to a training protocol and received balanced diet supplemented with 2% creatine. The blood lactate concentrations equivalent to maximal lactate steady state during treadmill running were analyzed at the beginning and also at the end of the experiment. At the end of the experiment were done comparing the test results MLSS between the two groups. At the beginning of the experiment, prior to groups division, the majority of animals obtained MLSS at a speed of26 m/min, blood lactate concentration of 3.79 ± 0.76 mmol/L. At the end of the experiment, most of trained rats in T presented MLSS at the speed of28 m/min, blood lactate concentration of 3.37 ± 0.68 mmol/L. Most TCr had MLSS at the speed of28 m/min, blood lactate concentration of 3.52 ± 0.69 mmol/L. We conclude that creatine supplementation was not the cause of the improvement in the aerobic capacity of rats in the tread-mill exercise. 展开更多
关键词 DIET LACTATE MAXIMAL LACTATE STEADY state TREADMILL running
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Dynamic Control System of Automatic Monitoring Equipment for Waste Gas Pollution Source
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作者 Yun WU Chengxin PAN Hanju BAO 《Asian Agricultural Research》 2021年第5期48-52,共5页
In order to improve the quality of automatic monitoring data of pollution sources and apply the automatic monitoring data to verify the environmental tax,Shandong Province took the lead in adopting the Internet of Thi... In order to improve the quality of automatic monitoring data of pollution sources and apply the automatic monitoring data to verify the environmental tax,Shandong Province took the lead in adopting the Internet of Things technology and drawing on the successful experience of air automatic monitoring stations and surface water automatic monitoring stations in management,and developed a dynamic management and control system for automatic monitoring equipment of pollution sources to improve and strengthen the quality audit of automatic monitoring data,further improve the quality of automatic monitoring data and better provide a basis for environmental management and decision making.The system realizes the simultaneous monitoring of monitoring data,running state and parameters of the automatic monitoring equipment,eliminates the phenomenon of falsification by modifying equipment parameters,and judges the validity of the collected data by acquiring the working state of the equipment remotely and randomly.After the actual operation test of the Department of Ecological Environment of Shandong Province,the system is proved to have the characteristics of practicality,real time and high efficiency,and be able to make up for low frequency and narrow coverage of manual inspection,with good application prospect in the field of environment and pollution source monitoring. 展开更多
关键词 Dynamic management and control Monitoring data running state Equipment parameter Negative control
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慢跑状态下跑鞋类型对跑步经济性的影响 被引量:4
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作者 崔昌水 《中国皮革》 CAS 2023年第2期97-100,共4页
跑步经济性是指维持某次极限特定跑步速度下的能量需求,是影响长跑成绩的主要原因,跑鞋类型对跑步经济有一定的影响,跑鞋类型选择不当会增加运动耗氧量、运动疲劳感,给人体的运动安全造成隐患。基于此,本文对跑步经济性的定义进行阐述,... 跑步经济性是指维持某次极限特定跑步速度下的能量需求,是影响长跑成绩的主要原因,跑鞋类型对跑步经济有一定的影响,跑鞋类型选择不当会增加运动耗氧量、运动疲劳感,给人体的运动安全造成隐患。基于此,本文对跑步经济性的定义进行阐述,分析了跑鞋的质量、类型和跑鞋抗弯度等因素对跑步经济性的影响。 展开更多
关键词 慢跑状态 跑鞋类型 跑步经济性 运动损伤
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低碳目标下的柔性流水车间调度及节能优化 被引量:3
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作者 尹瑞雪 吴拓 李洪丞 《机械设计与制造》 北大核心 2023年第4期281-286,共6页
为降低车间生产碳排放,对于具备不相关并行机环境的柔性流水车间,在分析了机床运行过程中不同状态下的碳排放的基础上,建立起一种以低碳为优化目标的调度数学模型。该模型不仅考虑了以往研究较少的搬运过程碳排放,同时还考虑了选定机床... 为降低车间生产碳排放,对于具备不相关并行机环境的柔性流水车间,在分析了机床运行过程中不同状态下的碳排放的基础上,建立起一种以低碳为优化目标的调度数学模型。该模型不仅考虑了以往研究较少的搬运过程碳排放,同时还考虑了选定机床的开关机过程的碳排放。基于该模型提出了在机床闲置等待期间降低碳排放的一种多状态更替的节能优化策略,并设计出改进的遗传算法对问题求解。最后利用相关案例,分析了模型的可行性,验证了节能优化策略的有效性。 展开更多
关键词 车间调度 运行状态 碳排放 改进遗传算法 节能
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Traditional Chinese medicine Qi model
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作者 Rui Chen 《TMR Theory and Hypothesis》 2020年第2期311-324,共14页
This paper expounds the effect of"Qi"on human body by constructing the model of Qi,classifies the parts according to the category of Yin and Yang on the coordinate frame of 5 models of Yin and Yang,and compa... This paper expounds the effect of"Qi"on human body by constructing the model of Qi,classifies the parts according to the category of Yin and Yang on the coordinate frame of 5 models of Yin and Yang,and compares each kind of parts according to the normal image state of human body.with the running direction of integer instead of Qi,the number of Qi in each part is calculated by the method of modern number theory,and the development and changes of human physiology and diseases are explained by"Qi".To explore the Trasitional Chinese Medicine treatment method of"the morbid Qi state of the human body adjusts the qi mode,the direction of qi operation and the intensity of Qi by means of medicinal taste and acupuncture,and returns to the normal state of qi balance mode in the direction of operation". 展开更多
关键词 Frame of reference Analogy of image acquisition Integer yin and yang Yin and yang number 5 model Image state QI Qi model state of Qi Qi mode running direction of Qi Qi number Qi intensity
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