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CPS Modeling of CNC Machine Tool Work Processes Using an Instruction-Domain Based Approach 被引量:17
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作者 Jihong Chen Jianzhong Yang +5 位作者 Huicheng Zhou Hua Xiang Zhihong Zhu Yesong Li Chen-Han Lee Guangda Xu 《Engineering》 SCIE EI 2015年第2期247-260,共14页
Building cyber-physical system(CPS) models of machine tools is a key technology for intelligent manufacturing. The massive electronic data from a computer numerical control(CNC) system during the work processes of a C... Building cyber-physical system(CPS) models of machine tools is a key technology for intelligent manufacturing. The massive electronic data from a computer numerical control(CNC) system during the work processes of a CNC machine tool is the main source of the big data on which a CPS model is established. In this work-process model, a method based on instruction domain is applied to analyze the electronic big data, and a quantitative description of the numerical control(NC) processes is built according to the G code of the processes. Utilizing the instruction domain, a work-process CPS model is established on the basis of the accurate, real-time mapping of the manufacturing tasks, resources, and status of the CNC machine tool. Using such models, case studies are conducted on intelligent-machining applications, such as the optimization of NC processing parameters and the health assurance of CNC machine tools. 展开更多
关键词 数控机床 过程教学 CPS 过程模型 建模 物理系统 智能制造 电子数据
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Modeling of microstructure evolution of AZ80 magnesium alloy during hot working process using a unified internal state variable method 被引量:4
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作者 Zexing Su Chaoyang Sun +2 位作者 Mingjia Wang Lingyun Qian Xintong Li 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2022年第1期299-313,共15页
In this paper, a unified internal state variable(ISV) model for predicting microstructure evolution during hot working process of AZ80 magnesium alloy was developed. A novel aspect of the proposed model is that the in... In this paper, a unified internal state variable(ISV) model for predicting microstructure evolution during hot working process of AZ80 magnesium alloy was developed. A novel aspect of the proposed model is that the interactive effects of material hardening, recovery and dynamic recrystallization(DRX) on the characteristic deformation behavior were considered by incorporating the evolution laws of viscoplastic flow, dislocation activities, DRX nucleation and boundary migration in a coupled manner. The model parameters were calibrated based on the experimental data analysis and genetic algorithm(GA) based objective optimization. The predicted flow stress, DRX fraction and average grain size match well with experimental results. The proposed model was embedded in the finite element(FE) software DEFORM-3 D via user defined subroutine to simulate the hot compression and equal channel angular extrusion(ECAE) processes. The heterogeneous microstructure distributions at different deformation zones and the dislocation density evolution with competitive deformation mechanisms were captured.This study can provide a theoretical solution for the hot working problems of magnesium alloy. 展开更多
关键词 AZ80 magnesium alloy Internal state variable model Microstructure evolution Dynamic recrystallization Hot working process Finite element simulation
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Processing map and hot working mechanisms of Cu-Ag alloy in hot compression process 被引量:6
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作者 王梦寒 黄龙 +1 位作者 陈明亮 王彦丽 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第3期821-828,共8页
For Gu-Ag alloy, an important parameter called workability in the forming process of materials can be evaluated by processing maps yielded from the stress-strain data generated by hot compression tests at temperatures... For Gu-Ag alloy, an important parameter called workability in the forming process of materials can be evaluated by processing maps yielded from the stress-strain data generated by hot compression tests at temperatures of 700-850 °C and strain rates of 0.01-10 s-1. And at the true strain of 0.15, 0.35 and 0.55, respectively, the responses of strain-rate sensitivity, power dissipation efficiency and instability parameter to temperature and strain rate were studied. Instability maps and power dissipation maps were superimposed to form processing maps, which reveal the determinate regions where individual metallurgical processes occur and the limiting conditions of flow instability regions. Furthermore, the optimal processing parameters for bulk metal working are identified clearly by the processing maps. 展开更多
关键词 地图叠加 铜银合金 压缩过程 应变率敏感性 热加工 机制 热压缩试验 稳定性参数
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Synthesis of indirect work exchange networks considering both isothermal and adiabatic process together with exergy analysis 被引量:2
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作者 Yu Zhuang Linlin Liu +1 位作者 Lei Zhang Jian Du 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第8期1644-1652,共9页
In this paper, an efficient methodology for synthesizing the indirect work exchange networks(WEN) considering isothermal process and adiabatic process respectively based on transshipment model is first proposed. In co... In this paper, an efficient methodology for synthesizing the indirect work exchange networks(WEN) considering isothermal process and adiabatic process respectively based on transshipment model is first proposed. In contrast with superstructure method, the transshipment model is easier to obtain the minimum utility consumption taken as the objective function and more convenient for us to attain the optimal network configuration for further minimizing the number of units. Different from division of temperature intervals in heat exchange networks,different pressure intervals are gained according to the maximum compression/expansion ratio in consideration of operating principles of indirect work exchangers and the characteristics of no pressure constraints for stream matches. The presented approach for WEN synthesis is a linear programming model applied to the isothermal process, but for indirect work exchange networks with adiabatic process, a nonlinear programming model needs establishing. Additionally, temperatures should be regarded as decision variables limited to the range between inlet and outlet temperatures in each sub-network. The constructed transshipment model can be solved first to get the minimum utility consumption and further to determine the minimum number of units by merging the adjacent pressure intervals on the basis of the proposed merging methods, which is proved to be effective through exergy analysis at the level of units structures. Finally, two cases are calculated to confirm it is dramatically feasible and effective that the optimal WEN configuration can be gained by the proposed method. 展开更多
关键词 间接 等温 合成 联网 交换网络 转运模型 网络配置 编程模型
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The Evaluation System Research based on the Working Process Systematization of the Practice Teaching Quality
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作者 Su Lin Hu Yang 《International Journal of Technology Management》 2013年第9期37-41,共5页
关键词 质量评价体系 教学质量 系统化 实践教学 设计理念 评价制度
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The heat and work of quantum thermodynamic processes with quantum coherence
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作者 苏山河 陈劲夫 +2 位作者 马宇翰 陈金灿 孙昌璞 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第6期195-202,共8页
Energy is often partitioned into heat and work by two independent paths corresponding to the change in the eigenenergies or the probability distributions of a quantum system. The discrepancies of the heat and work for... Energy is often partitioned into heat and work by two independent paths corresponding to the change in the eigenenergies or the probability distributions of a quantum system. The discrepancies of the heat and work for various quantum thermodynamic processes have not been well characterized in literature. Here we show how the work in quantum machines is differentially related to the isochoric, isothermal, and adiabatic processes. We prove that the energy exchanges during the quantum isochoric and isothermal processes are simply depending on the change in the eigenenergies or the probability distributions. However, for a time-dependent system in a non-adiabatic quantum evolution, the transitions between the different quantum states representing the quantum coherence can affect the essential thermodynamic properties, and thus the general definitions of the heat and work should be clarified with respect to the microscopic generic time-dependent system. By integrating the coherence effects in the exactly-solvable dynamics of quantum-spin precession, the internal energy is rigorously transferred as the work in the thermodynamic adiabatic process. The present study demonstrates that the quantum adiabatic process is sufficient but not necessary for the thermodynamic adiabatic process. 展开更多
关键词 heat and work thermodynamic adiabatic process quantum coherence
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MY WORK ON THE EPICENTRAL PROCESS OF EARTHQUAKES
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作者 Chen Yuntai(Institute of Geophysics under the State Seismic Administration) 《Bulletin of the Chinese Academy of Sciences》 1995年第3期278-278,共1页
In 1962, I graduated from the faculty of geophysics of Beijing University and was admitted to a postgraduate program at the CAS Institute of Geophysics after an entrance examination in the same year. During the past 3... In 1962, I graduated from the faculty of geophysics of Beijing University and was admitted to a postgraduate program at the CAS Institute of Geophysics after an entrance examination in the same year. During the past 30 years, I have been invariabl.y engaged in theoretic and applied research of the seismic wave and its epicenter.Since the early 1970s, my work has shifted to the epicentral process, applying research results to abstracting epicentral information from seismic wave data, "zero fre- 展开更多
关键词 In work MY work ON THE EPICENTRAL process OF EARTHQUAKES CAS
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Work Organization at Farm Level: A Process-Led Approach to Understand Land Use Changes
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作者 S. Madelrieux L. Dobremez B. Dedieu 《Journal of Agricultural Science and Technology》 2010年第4期57-66,共10页
关键词 土地利用变化 农场 组织 阿尔卑斯山 导向 土地集约利用 活动序列 工作流程
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MY WORK FOR UPDATING PETROCHEMICAL CATALYSIS AND PROCESSING
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作者 Lin Liwu(Dalian Institute of Chemical Physics. CAS) 《Bulletin of the Chinese Academy of Sciences》 1996年第1期72-73,共2页
After graduating from Zhejiang University in 1952, I came to work at the Institute of Petroleum Processing (which was renamed the Dalian Institute of Chemical Physics in 1959) under the CAS in Dalian City and served a... After graduating from Zhejiang University in 1952, I came to work at the Institute of Petroleum Processing (which was renamed the Dalian Institute of Chemical Physics in 1959) under the CAS in Dalian City and served as a research chemist there. In the 1950s,my research interest was mainly concentrated on synthetic liquid fuels. After the discovery of a large oilfield in the Daqing area in 1960, a great impetus was brought to the 展开更多
关键词 MY work FOR UPDATING PETROCHEMICAL CATALYSIS AND processING CAS high Pt
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Humanoid Based Intelligence Control Strategy of Plastic Cement Die Press Work-Piece Forming Process for Polymer Plastics
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作者 Dekuan Liu Shuang Jin Hu Xu 《Journal of Materials Science and Chemical Engineering》 2016年第6期9-16,共8页
The plastic cement belongs to a sort of polymer material, the chemical composition is very complex, and the plastic cement work-piece is generally manufactured by die press forming. Aimed at being difficult to control... The plastic cement belongs to a sort of polymer material, the chemical composition is very complex, and the plastic cement work-piece is generally manufactured by die press forming. Aimed at being difficult to control in parameters of forming process, the paper explored the humanoid based intelligence control strategy. In the paper, it made the anatomy in control puzzle resulted in uncertainty such as chemical component of plastic cement etc., summarized up the characteristic of cybernetics in forming process, researched on the humanoid based intelligence control strategy, and constructed the control algorithm of forming process in plastic cement work-piece. Taking the process experiment of temperature and pressure control as an example, it validated the good dynamic and static control quality through simulation of control algorithm constructed in this paper. The experimental results show that the control algorithm explored in this paper is reasonably available. 展开更多
关键词 Plastic Cement Polymer Plastics Die Press work-Piece Forming process Humanoid Based Intelligence Control
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Auditory Temporal Processing and Working Memory: Two Independent Deficits for Dyslexia
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作者 Leah Fostick Sharona Bar-El Ronit Ram-Tsur 《Psychology Research》 2012年第5期308-318,共11页
关键词 时间处理 记忆 听觉 阅读能力 财政 认知功能障碍 测试工作 遗传基础
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专业群“模块递进、项目贯穿”工作过程导向的实践教学体系改革与实践——以电气自动化技术专业群为例
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作者 井新宇 《四川职业技术学院学报》 2024年第1期1-5,共5页
高职院校专业群建设的实质,就是依据产业和人才培养逻辑对群内专业进行有效整合,实现资源共享,凸显群效应,服务产业对人才的需求。明确专业群服务产业的人才培养定位,理清专业群内各专业能力培养的自身特色以及服务产业的逻辑关联。以... 高职院校专业群建设的实质,就是依据产业和人才培养逻辑对群内专业进行有效整合,实现资源共享,凸显群效应,服务产业对人才的需求。明确专业群服务产业的人才培养定位,理清专业群内各专业能力培养的自身特色以及服务产业的逻辑关联。以课程为本搭建实践能力递进模块,以工作过程为导向开发课程,项目贯穿设计专业群实践教学体系。建设工程化的实践环境,利用信息化管理手段,推动过程评价和增值评价,持续改进培养质量,融“三教”改革于项目化教学,实现专业群高水平服务学生成长成才,高质量服务区域经济发展,适应产业发展新形势和新业态的要求。 展开更多
关键词 专业群 模块 工作过程 项目贯穿 实践教学体系 “三教”改革
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中小企业安全管理员工作异化形成机理研究
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作者 杨道建 傅磊 刘素霞 《安全与环境学报》 CAS CSCD 北大核心 2024年第4期1477-1484,共8页
为探明中小企业安全管理员工作异化的原因及形成机理,进而提出针对性防范措施,深度访谈中小企业的25名安全管理员,采用“情境过程”框架,遵循扎根理论程序,建构了中小企业安全管理员工作异化形成机理模型,并分析了相关因素对中小企业安... 为探明中小企业安全管理员工作异化的原因及形成机理,进而提出针对性防范措施,深度访谈中小企业的25名安全管理员,采用“情境过程”框架,遵循扎根理论程序,建构了中小企业安全管理员工作异化形成机理模型,并分析了相关因素对中小企业安全管理员工作异化的影响。结果表明:当地应急管理部门、中小企业领导和员工在各自行为逻辑主导下,受内外部情境影响,分别选择形式化监管、模糊性问责,应付式管理、表面化支持,象征性参与和折扣性执行的行为策略。受这些行为策略的刺激,中小企业安全管理员产生自保、同情员工等心理,进而对应选择盲目追随、避责为先,一味顺从、不争权利,放宽要求、处罚宽松等行为策略,最终导致工作异化发生。 展开更多
关键词 安全社会科学 安全管理员 工作异化 情境过程 扎根理论
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基于工作过程的“机械制造工艺与夹具”课程线上线下混合式教学设计研究
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作者 尹亮 《鹿城学刊》 2024年第1期88-90,120,共4页
文章结合国内现有的“机械制造工艺与夹具”课程教学研究成果和教学经验,基于课情和学情分析,从总体思路、课程思政、教学内容、教学模式及组织形式、教学方法手段及重难点突破、技能训练项目任务书、教学评价等7个维度,探讨了一种基于... 文章结合国内现有的“机械制造工艺与夹具”课程教学研究成果和教学经验,基于课情和学情分析,从总体思路、课程思政、教学内容、教学模式及组织形式、教学方法手段及重难点突破、技能训练项目任务书、教学评价等7个维度,探讨了一种基于工作过程、岗课赛证一体融通的“机械制造工艺与夹具”课程线上线下混合式教学设计。经三年的教学实践证明,效果明显优于以往的教学设计。 展开更多
关键词 课情 学情 教学设计 工作过程 岗课赛证
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Combining a Safety Management Process with a Safety Framework
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作者 Derrick Black Elizabeth Hull Ken Jackson 《Intelligent Information Management》 2010年第4期233-242,共10页
A safety document management system, known as a Permit for Work (PFW) system is used commonly in the Power Industry to provide appropriate safety conditions for those working on the generating system. This paper inves... A safety document management system, known as a Permit for Work (PFW) system is used commonly in the Power Industry to provide appropriate safety conditions for those working on the generating system. This paper investigates how a safety management process (+PFW) can be combined with a safety framework to enhance system effectiveness to ensure the requirements of users and suppliers can be met. While the paper makes some reference to the power industry, the concept is applicable to the management of systems in other domains. 展开更多
关键词 SAFETY Permit for work Systems Engineering Power INDUSTRY HEALTH and SAFETY process Modelling FRAMEwork
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论数据要素主体的权利保护——以视听作品保护模式为参照
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作者 孙阳 《电子知识产权》 2024年第5期45-56,共12页
数据要素主体的权利保护是围绕数据要素主体行为的制度规则设计,重点在于合理分配数据行为过程中数据要素主体的预期收益。数据产品作为数据行为过程的产物,凝结了数据要素主体共同的投入。数据产品的价值是数据要素主体预期收益的主要... 数据要素主体的权利保护是围绕数据要素主体行为的制度规则设计,重点在于合理分配数据行为过程中数据要素主体的预期收益。数据产品作为数据行为过程的产物,凝结了数据要素主体共同的投入。数据产品的价值是数据要素主体预期收益的主要来源,而数据要素主体的贡献则是分配预期收益的衡量依据。数据要素主体的结构行为特征与视听作品权利保护模式,要求数据要素主体的权利保护制度设计应当遵循一定的规范原则,以实现数据行为过程中数据要素主体合法权利充分实现和保障的制度目标。一方面,坚持优先保护特定数据要素主体的规范原则,通过规则内容确立特定主体的权利构成和权益地位;另一方面,坚持构建共识的规范原则,保障数据价值实现过程的稳定性。 展开更多
关键词 数据要素主体 数据行为 视听作品 优先保护
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自复叠制冷技术研究进展
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作者 孙欢 杨凯 +1 位作者 吴冬夏 康博强 《冷藏技术》 2024年第1期79-85,48,共8页
自复叠制冷技术在低温领域的应用十分广泛。本文首先介绍了自复叠制冷技术的原理,并与单级压缩、多级压缩及复叠制冷技术进行比较,指出了自复叠制冷技术具有结构简单、制冷温区宽的优势。从自复叠制冷系统的循环特性、混合工质的选择和... 自复叠制冷技术在低温领域的应用十分广泛。本文首先介绍了自复叠制冷技术的原理,并与单级压缩、多级压缩及复叠制冷技术进行比较,指出了自复叠制冷技术具有结构简单、制冷温区宽的优势。从自复叠制冷系统的循环特性、混合工质的选择和配比优化、系统流程优化三方面,对当前自复叠制冷技术的研究进行分析总结。最后,展望该技术的发展前景,为拓宽该技术的应用提供参考。 展开更多
关键词 自复叠制冷 循环特性 混合工质 系统流程优化
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基于计算机视觉的常用玻璃量器自动检定装置
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作者 陈洁 张巍 +1 位作者 李斌 田芙蓉 《自动化与仪表》 2024年第2期86-91,共6页
玻璃量器作为常规配套设备,其需求量日益增长,常用玻璃量器的检定任务越来越重,传统的人工检定已不能满足日益增长的业务需求。该文提出了一种图像法和反馈控制技术相结合的容量示值检定自动化技术,即一种基于图像处理的常用玻璃量器检... 玻璃量器作为常规配套设备,其需求量日益增长,常用玻璃量器的检定任务越来越重,传统的人工检定已不能满足日益增长的业务需求。该文提出了一种图像法和反馈控制技术相结合的容量示值检定自动化技术,即一种基于图像处理的常用玻璃量器检定自动化装置,主要解决加液自动化功能、容量示值读数自动化功能。开发集数据采集、处理、原始记录生成、报告打印等多功能于一体的软件系统。 展开更多
关键词 玻璃量器 量器检定 图像处理 自动加液 液位检测
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基于工作过程的地质工程专业教学设计与策略研究--以地质灾害防治课程设计为例
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作者 崔圣华 范宣梅 +3 位作者 裴向军 杨峥 杨晴雯 蒋涛 《高教学刊》 2024年第1期115-118,共4页
四川省是全国地质灾害较为频发的省份,其勘察行业对地质灾害防治设计相关人才需求量大。该文以勘察行业需求为基础,通过地质防治设计岗位和典型工作过程分析,构建地质灾害防治基于工作过程的课程体系,设计出工程设计专题讲解、工程设计... 四川省是全国地质灾害较为频发的省份,其勘察行业对地质灾害防治设计相关人才需求量大。该文以勘察行业需求为基础,通过地质防治设计岗位和典型工作过程分析,构建地质灾害防治基于工作过程的课程体系,设计出工程设计专题讲解、工程设计环节、项目评审环节和项目总结交流的四阶段教学过程,通过模拟实际工作环节和设计过程,培养学生的地灾防治工程设计能力和职业素养。 展开更多
关键词 工作过程 地质灾害 教学设计 课程设计 课程体系
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生态环境治理项目安全生产标准化评价模型及其应用
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作者 张扬 《安全与环境工程》 CAS CSCD 北大核心 2024年第2期1-8,43,共9页
为提高生态环境治理项目安全生产标准化评价的准确性和客观性,针对安全生产标准化存在的管理缺陷及主要问题,首先结合相关文献和项目实际确定安全生产标准化评价指标体系,然后采用层次分析法计算各评价指标的权重,构建了安全生产标准化... 为提高生态环境治理项目安全生产标准化评价的准确性和客观性,针对安全生产标准化存在的管理缺陷及主要问题,首先结合相关文献和项目实际确定安全生产标准化评价指标体系,然后采用层次分析法计算各评价指标的权重,构建了安全生产标准化评价模型,最后应用安全生产标准化评价模型对某土地开发整理项目进行了实例应用与分析。结果表明,该评价模型适用于生态环境治理项目安全生产标准化量化评分,对今后生态环境治理项目安全生产标准化评价具有指导意义。 展开更多
关键词 生态环境治理项目 安全生产标准化 评价模型 层次分析法
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