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Key technologies and applications of intelligent dispatching command for high-speed railway in China
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作者 Shuxin Ding Tao Zhang +2 位作者 Kai Sheng Yuanyuan Chen Zhiming Yuan 《Railway Sciences》 2023年第3期336-346,共11页
Purpose–The intelligent Central Traffic Control(CTC)system plays a vital role in establishing an intelligent high-speed railway(HSR)system.As the core of HSR transportation command,the intelligent CTC system is a new... Purpose–The intelligent Central Traffic Control(CTC)system plays a vital role in establishing an intelligent high-speed railway(HSR)system.As the core of HSR transportation command,the intelligent CTC system is a new HSR dispatching command system that integrates the widely used CTC in China with the practical service requirements of intelligent dispatching.This paper aims to propose key technologies and applications for intelligent dispatching command in HSR in China.Design/methodology/approach–This paper first briefly introduces the functions and configuration of the intelligent CTC system.Some new servers,terminals and interfaces are introduced,which are plan adjustment server/terminal,interface for automatic train operation(ATO),interface for Dynamic Monitoring System of Train Control Equipment(DMS),interface for Power Supervisory Control and Data Acquisition(PSCADA),interface for Disaster Monitoring,etc.Findings–The key technologies applied in the intelligent CTC system include automatic adjustment of train operation plans,safety control of train routes and commands,traffic information data platform,integrated simulation of traffic dispatching and ATO function.These technologies have been applied in the Beijing-Zhangjiakou HSR,which commenced operations at the end of 2019.Implementing these key intelligent functions has improved the train dispatching command capacity,ensured the safe operation of intelligent HSR,reduced the labor intensity of dispatching operators and enhanced the intelligence level of China’s dispatching system.Originality/value–This paper provides further challenges and research directions for the intelligent dispatching command of HSR.To achieve the objectives,new measures need to be conducted,including the development of advanced technologies for intelligent dispatching command,coping with new requirements with the development of China’s railway signaling system,the integration of traffic dispatching and train control and the application of AI and data-driven modeling and methods. 展开更多
关键词 high-speed railway Intelligent dispatching command Intelligent centralized traffic control Key technologies and application
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Progress in high-speed train technology around the world 被引量:9
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作者 Li ZHOU Zhiyun SHEN 《Journal of Modern Transportation》 2011年第1期1-6,共6页
This is a review of high-speed train development in the sense of technology advances all over the world. Three generations of high-speed trains are classified according to their technical characteristics and maximum o... This is a review of high-speed train development in the sense of technology advances all over the world. Three generations of high-speed trains are classified according to their technical characteristics and maximum operating speed. Emphasis is given to the newly developed high-speed train in China, CRH380. The theoretical foundations and future development of CRH380 are briefly discussed. 展开更多
关键词 high-speed railway high-speed train technology maximum operating speed vehicle system dynamics service reliability
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Failure mechanism and control technology of longwall coalface in large-cutting-height mining method 被引量:7
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作者 Wang Jiachen Yang Shengli Kong Dezhong 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第1期111-118,共8页
The stability control of longwall coalface is the key technology of large-cutting-height mining method.Therefore,a systematic study of the factors that affect coalface stability and its control technology is required ... The stability control of longwall coalface is the key technology of large-cutting-height mining method.Therefore,a systematic study of the factors that affect coalface stability and its control technology is required in the development of large-cutting-height mining method in China. After the practical field observation and years of study,it was found that the more than 95% of failures in coalface are shear failure. The shear failure analysis model of coalface has been established,that can perform systematic study among factors such as mining height,coal mass strength,roof load,support resistance,and face flipper protecting plate horizontal force. Meanwhile,sensitivity analysis of factors influencing coalface stability showed that improving support capacity,cohesion of coal mass and decreasing roof load of coalface are the key to improve coalface stability. Numerical simulation of the factors affecting coalface stability has been performed using UDEC software and the results are consistent with the theoretical analysis. The coalface reinforcement technology of large-cutting-height mining method using the grouting combined with coir rope is presented. Laboratory tests have been carried out to verify its reinforcement effect and practical application has been implemented in several coal mines with good results.It has now become the main technology to reduce longwall coalface failure of large-cutting-height mining method. 展开更多
关键词 长壁工作面 控制技术 开采方法 失效机理 大采高 顶板稳定性 采煤工作面 煤体强度
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Key Technology of Cutting and Moving Large Spherical Tank
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作者 YANG Wei LIU Xinshang HU Xuefeng 《International Journal of Plant Engineering and Management》 2021年第3期167-179,共13页
This paper mainly introduces the scientific cutting and hoisting construction technology before the large spherical tank(hereinafter referred to as spherical tank)moving and loading,so as to better ensure the construc... This paper mainly introduces the scientific cutting and hoisting construction technology before the large spherical tank(hereinafter referred to as spherical tank)moving and loading,so as to better ensure the construction quality of field assembly and welding in the process of spherical tank moving and loading. 展开更多
关键词 spherical tank moving and loading cutting and hoisting technology
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GERBER TECHNOLOGY LAUNCHES FIRST OF NEW SERIES OF CUTTING SOLUTIONS
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《China Textile》 2008年第7期9-10,共2页
Precision, Productivity and Performance def ine the GERBERcutter? Z7Tolland, Conn., USA – Gerber Technology, a business unit of Gerber Scientific, Inc. (NYSE: GRB), and the world leader in providing innovative integr... Precision, Productivity and Performance def ine the GERBERcutter? Z7Tolland, Conn., USA – Gerber Technology, a business unit of Gerber Scientific, Inc. (NYSE: GRB), and the world leader in providing innovative integrated software and hardware automation systems to 展开更多
关键词 GERBER technology LAUNCHES FIRST OF NEW SERIES OF cutting SOLUTIONS VOC
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New technologies for high-risk tunnel construction in GuiyangGuangzhou high-speed railway 被引量:2
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作者 Yubao Zhao Shougen Chen +1 位作者 Xinrong Tan Ma Hui 《Journal of Modern Transportation》 2013年第4期258-265,共8页
Based on the construction of high risk tunnels in Guiguang-Guangzhou high-speed railway, several new technologies were developed for high-risk tunnel con- struction. First, an integrated advanced geological predic- ti... Based on the construction of high risk tunnels in Guiguang-Guangzhou high-speed railway, several new technologies were developed for high-risk tunnel con- struction. First, an integrated advanced geological predic- tion was developed for tunneling in karst area. Then, a new system of ventilation by involving the dedusting technol- ogy was proposed and used in the field, which received a good air quality. Finally, a method to minimize the dis- tance between the working face and the invert installation was proposed by optimizing the invert installation and adopting the micro bench method. Applying the method to the project obtained an excellent result. The achievement obtained for this study would be able to provide a valuable reference to similar projects in the future. 展开更多
关键词 Tunneling engineering high-speed railway New technologies High-risk tunnel
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Study on 5G Application Scenarios in Intelligent High-Speed Railway
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作者 LI Ping LUAN Zhong +3 位作者 LIU Ziyuan CHENG Zhibo XIE Chenhui ZHANG Yiran 《Chinese Railways》 2023年第1期45-53,共9页
5G technology is indispensable for developing comprehensive perception and ubiquitous interconnection of intelligent high-speed railways(HSRs),and can be applied to many scenarios in intelligent construction,intellige... 5G technology is indispensable for developing comprehensive perception and ubiquitous interconnection of intelligent high-speed railways(HSRs),and can be applied to many scenarios in intelligent construction,intelligent equipment,intelligent operation and in other fields.In order to promote the standardized application of 5G technology in intelligent HSRs in a scientific and orderly manner and to avoid redundant construction and wasteful investment,it is imperative to carry out a systematical top-level design of the application scenarios at the initial stage.To this end,after investigating and analyzing the 5G application demands in different aspects of HSRs and the general structure of the railway 5G network,this paper formulates an overall planning of 5G technology application scenarios and proposes solutions to some typical application scenarios in the intelligent HSR system,based on the architecture and requirements of the intelligent HSR system. 展开更多
关键词 intelligent high-speed railway 5G technology COMMUNICATION application scenarios
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Fracture mechanics analysis on Smart-Cut~ technology.Part 1:Effects of stiffening wafer and defect interaction 被引量:3
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作者 Bin Gu Hongyuan Liu +2 位作者 Yiu-Wing Mai Xi Qiao Feng Shou Wen Yu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2009年第1期73-81,共9页
In the present paper, continuum fracture mechanics is used to analyze the Smart-Cut process, a recently established ion cut technology which enables highly efficient fabrication of various silicon-on-insulator (SOI)... In the present paper, continuum fracture mechanics is used to analyze the Smart-Cut process, a recently established ion cut technology which enables highly efficient fabrication of various silicon-on-insulator (SOI) wafers of high uniformity in thickness. Using integral transform and Cauchy singular integral equation methods, the mode-I and mode-II stress intensity factors, energy release rate, and crack opening displacements are derived in order to examine several important fracture mechanisms involved in the Smart-Cut process. The effects of defect interaction and stiffening wafer on defect growth are investigated. The numerical results indi- cate that a stiffener/handle wafer can effectively prevent the donor wafer from blistering and exfoliation, but it slows down the defect growth by decreasing the magnitudes of SIF's. Defect interaction also plays an important role in the splitting process of SOI wafers, but its contribution depends strongly on the size, interval and internal pressure of defects. Finally, an analytical formula is derived to estimate the implantation dose required for splitting a SOI wafer. 展开更多
关键词 Smart-cut technology Silicon-on-insulatorwafer Crack growth Fracture mechanics Stress intensityfactor
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Fracture mechanics analysis on Smart-Cut~technology.Part 2:Effect of bonding flaws 被引量:1
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作者 Bin Gu Hongyuan Liu +2 位作者 Yiu-Wing Mai Xi Qiao Feng ShouWen Yu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2009年第2期197-203,共7页
In Part 2 of the paper on the Smart-Cut process, the effects of bonding flaws characterized by the size and internal pressure before and after splitting are studied by using fracture mechanics models. It is found that... In Part 2 of the paper on the Smart-Cut process, the effects of bonding flaws characterized by the size and internal pressure before and after splitting are studied by using fracture mechanics models. It is found that the bonding flaws with large size are prone to cause severe deviation of defect growth, leading to a non-transferred area of thin layer when splitting. In a practical Smart-Cut process where the internal pressure of bonding flaws is very small, large interfacial defects always promote defect growth in the splitting process. Meanwhile, increasing the internal pressure of the bonding flaws decreases the defect growth and its deviation before splitting. The mechanism of relaxation of stiffener constraint is proposed to clarify the effect of bonding flaws. Moreover, the progress of the splitting process is analyzed when bonding flaws are present. After splitting, those bonding flaws with large size and high internal pressure are vulnerable for the blistering of the thin film during high-temperature annealing. 展开更多
关键词 Smart-cut technology Fracture mechanics Stress intensity factor Interfacial defect
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Generalized equation for calculating rock cutting efficiency by pulsed water jets 被引量:6
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作者 Andrey Polyakov Aleksandr Zhabin +1 位作者 Eugene Averin Aleksey Polyakov 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2019年第4期867-873,共7页
One of the promising methods for rock cutting technology is the use of high-speed water jets.In order to improve the cutting capacity of water jets without increasing the hydraulic power of equipment,pulsed water jets... One of the promising methods for rock cutting technology is the use of high-speed water jets.In order to improve the cutting capacity of water jets without increasing the hydraulic power of equipment,pulsed water jets are basically used to increase the rock cutting efficiency.However,there are no mature recommendations for selection of rational parameters,and the relationship between indicators of rock cutting efficiency and parameters of pulsed water jet is still not established.In this context,we aimed at developing a generalized equation for calculating rock cutting efficiency,in which all the major parameters in consideration of rock cutting process are included.Then,a calibration of the rational parameters of rock cutting by pulsed water jets was conducted.The results are likely helpful for increasing productivity and reducing energy consumption. 展开更多
关键词 PULSED WATER jets Rock cutting WATER JET technology Generalized equation Depth of cut
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Exploring the silvicultural and economic viability of gap cutting in Mediterranean softwood plantations
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作者 Roberto MERCURIO Raffaele SPINELLI 《Forestry Studies in China》 CAS 2012年第1期63-69,共7页
Gap cutting consists of the removal of all trees growing on a small surface, varying in size from 200 to 600 m2. In Italy, gap cutting has been successfully tested for introducing the natural regeneration of native sp... Gap cutting consists of the removal of all trees growing on a small surface, varying in size from 200 to 600 m2. In Italy, gap cutting has been successfully tested for introducing the natural regeneration of native species into softwood plantations, thus ac- celerating the transition towards climax hardwood stands. Depending on plantation types and conditions, gap cutting should be start- ed at an age between 70 and 80 years and the system should include at least 12 to 15 gaps, in order to produce enough wood to cover costs. Generally, natural regeneration is firmly established within 5-7 years from treatment. Gap cutting also offers superior results to selection thinning, the latter producing about 35% less value and incurring 25% to 30% more costs. As for all regeneration cuts, the success of gap cutting depends on wildlife control in order to prevent extensive damage to the regeneration. 展开更多
关键词 gap cutting REGENERATION plantations ECONOMICS technology
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The status and prospects of in situ grain harvesting technology and its machine system
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作者 Jiang Yiyuan Xu Jiamei Du Chenghai 《Journal of Northeast Agricultural University(English Edition)》 CAS 1994年第1期68-75,共8页
Two main types of in situ grain harvesttng machine are introduced. The comparison of their working principles and advantages are given. The limitations and prospects for stripper header are discussed.
关键词 in situ harvesting technology stripper header threshing prior to cutting
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A survey of digital paper-cutting 被引量:1
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作者 LEI Hongyuan 《Computer Aided Drafting,Design and Manufacturing》 2012年第3期12-17,共6页
Paper-cutting is one of the most fantastic Chinese folk arts. With the aid of computers, digital paper-cutting has become a popular topic in the field of NPR research. This paper will make a comprehensive survey of re... Paper-cutting is one of the most fantastic Chinese folk arts. With the aid of computers, digital paper-cutting has become a popular topic in the field of NPR research. This paper will make a comprehensive survey of related references in four as- pects-image-based paper-cutting, paper-cutting based on computer graphics, paper architectures and paper-cutting animation and it shows that the imitation of the masters' artistic styles of paper-cutting will be the trend of future study. 展开更多
关键词 PAPER-cutting digital technology non-photorealistic RENDERING THRESHOLDING black and white GRAPHICS
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聚四氟乙烯材料切削工艺和应用研究进展
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作者 倪敬 崔智 +2 位作者 何利华 付新 朱泽飞 《中国机械工程》 EI CAS CSCD 北大核心 2024年第3期498-514,共17页
聚四氟乙烯(polytetrafluoroethylene,PTFE)因其优异的物理化学性能而成为生产制造电子通信、航空航天等领域关键零部件的重要材料。相比模压烧结工艺,切削工艺能够更高效地加工结构较为复杂的PTFE零部件。然而,PTFE材料具有韧性强、回... 聚四氟乙烯(polytetrafluoroethylene,PTFE)因其优异的物理化学性能而成为生产制造电子通信、航空航天等领域关键零部件的重要材料。相比模压烧结工艺,切削工艺能够更高效地加工结构较为复杂的PTFE零部件。然而,PTFE材料具有韧性强、回弹性高、导热性差和线膨胀系数大等特点,使得其切削加工质量难以保证,在一些特殊领域,对PTFE零部件的表面洁净度更是有极高的要求,这些都对PTFE材料的切削工艺提出了新的挑战。从PTFE材料的基础力学和物理化学等特性出发,总结了PTFE材料的切削加工性;结合聚合物切削理论及其研究方法分析了PTFE材料的切削去除机理;阐述了PTFE及其复合材料的车、铣、钻等切削加工工艺;最后概述了PTFE材料切削工艺在相关重要领域的应用现状,并从材料性能研究、基础切削理论研究、切削工艺探索等方面总结了现有研究和应用中存在的问题,对未来研究的发展趋势和研究重点进行了展望。 展开更多
关键词 聚四氟乙烯 切削机理 切削工艺 力学性能
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油气井井下切割技术发展现状及趋势
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作者 蔡灿 曾浪 +4 位作者 刘家炜 樊康康 曹文洋 周圣文 曾薪 《西安石油大学学报(自然科学版)》 北大核心 2024年第1期89-96,113,共9页
油气开发后期,退役井数量急剧增加,完井修井作业中套管磨损、卡钻等问题突出,退役经济耗费显著增加。为最大限度减少卡钻和退役经济耗费,有必要开展新型套管切割技术及装备的研发与应用。首先,总结了现阶段井下管柱切割技术的主要类型... 油气开发后期,退役井数量急剧增加,完井修井作业中套管磨损、卡钻等问题突出,退役经济耗费显著增加。为最大限度减少卡钻和退役经济耗费,有必要开展新型套管切割技术及装备的研发与应用。首先,总结了现阶段井下管柱切割技术的主要类型、工作原理和配套装备,包括机械切割、磨料射流切割、聚能切割、化学切割、电弧切割以及激光切割;对比机械切割、磨料射流切割以及特种切割方式的技术发展现状和趋势,分析上述切割方式的工程应用及优缺点;在此基础上,提出面向高效套管切割工程需求的主要切割技术及工具。结合目前切割技术及工具的发展现状,对未来井下管柱切割技术给出优化割刀性能、加强磨料射流切割的控制、研制新型切割工具及切割工具智能化等建议。 展开更多
关键词 井下工具 切割技术 机械切割 磨料射流切割 特种切割
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科研反哺教学在林木育种学教学中的探索与实践
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作者 任亚超 张军 +1 位作者 王进茂 杨敏生 《安徽农业科学》 CAS 2024年第10期278-282,共5页
林木育种学是高等农林院校林学专业的一门骨干课程,是以遗传进化理论为指导,研究林木优良品种选育、繁殖原理和技术的学科。其最高目标是选育林木优良品种,为林业生产提供最基本、最优质、最高效的生产资料,是林业的命脉和促进林业产业... 林木育种学是高等农林院校林学专业的一门骨干课程,是以遗传进化理论为指导,研究林木优良品种选育、繁殖原理和技术的学科。其最高目标是选育林木优良品种,为林业生产提供最基本、最优质、最高效的生产资料,是林业的命脉和促进林业产业发展的原动力,在生态文明和美丽中国建设中发挥着越来越重要的作用。为了使学生更容易理解和掌握林木育种学的理论知识,深化科教融合,推进创新型人才培养,完善协同育人机制,在林木育种学授课过程中,通过将理论知识与生产实践相联系,将科技前沿贯穿于课堂教学,并以科研平台辅助实验教学的方式进行教学改革,不仅丰富了教学内容,激发了学生的学习热情,加深了对理论知识的理解,而且还利于学生良好科研素养的培养及创新能力的提高。 展开更多
关键词 林木育种学 科研反哺教学 教学改革 科研基地 科技前沿
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思政元素融入技术前沿进展课程——以材料与化工专业为例
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作者 廖建国 马婷婷 +1 位作者 曹新鑫 管学茂 《科技资讯》 2024年第2期1-4,共4页
专业型硕士研究生培养应具有“学术型”“实践性”“职业性”的特点,以党的二十大精神为指引,落实立德树人根本任务,发展素质教育,为培养德智体美全面发展的社会主义建设者和接班人。河南理工大学材料学院材料与化工专业“技术前沿进展... 专业型硕士研究生培养应具有“学术型”“实践性”“职业性”的特点,以党的二十大精神为指引,落实立德树人根本任务,发展素质教育,为培养德智体美全面发展的社会主义建设者和接班人。河南理工大学材料学院材料与化工专业“技术前沿进展”课程教育与思想政治教育进行有机结合,任课教师将课程思政贯穿于“技术前沿进展”整个教学体系,通过思政元素的引入以及案例分析教学强调主流价值引领,培养了专业型硕士的社会责任感和使命感。 展开更多
关键词 技术前沿进展 课程思政 专业型硕士 人才培养
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中国服务贸易开放与制造业对外价值链关联
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作者 胡昭玲 逯洋 范龙飞 《经济经纬》 北大核心 2024年第2期53-64,共12页
在理论阐释服务贸易开放影响中外双边价值链关联紧密度的基础上,利用中国制造业行业数据检验了影响效果及作用机制。研究发现:服务贸易开放程度的提高有利于促进中外价值链关联紧密度的提升,该结论经过一系列稳健性检验依然成立。机制... 在理论阐释服务贸易开放影响中外双边价值链关联紧密度的基础上,利用中国制造业行业数据检验了影响效果及作用机制。研究发现:服务贸易开放程度的提高有利于促进中外价值链关联紧密度的提升,该结论经过一系列稳健性检验依然成立。机制检验发现,服务贸易开放主要通过贸易成本削减效应和技术创新效应影响双边价值链关联。异质性分析表明,服务贸易开放引致的价值链关联效应在低技术制造业行业、发展中国家中更为显著,并且表现出较强的“地理邻近性”特征,即与亚洲国家间的价值链关联效应更为突出。拓展分析发现,国家数字基础设施水平在服务贸易开放对中外双边价值链关联的促进效应中存在显著的正向调节作用。研究结论意味着推动服务业高水平开放、完善数字基础设施建设是推动我国制造业深度参与全球价值链分工,提升国际产业链竞争力的重要抓手。 展开更多
关键词 服务贸易开放 制造业服务化 价值链关联 成本削减效应 技术创新效应
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激光技术在塑料加工中的应用与案例
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作者 陶永亮 《橡塑技术与装备》 CAS 2024年第4期26-31,共6页
激光技术在工业中应用得到了很大的发展,尤其在塑料加工中应用逐步取代传统的加工方式,这对塑料加工质量和加工效率等都有较好地成效。本文就激光原理、特点与类型作些介绍,围绕了激光技术在塑料加工中应用作了描述,结合对3D打印、切割... 激光技术在工业中应用得到了很大的发展,尤其在塑料加工中应用逐步取代传统的加工方式,这对塑料加工质量和加工效率等都有较好地成效。本文就激光原理、特点与类型作些介绍,围绕了激光技术在塑料加工中应用作了描述,结合对3D打印、切割(打孔)、焊接、表面打标、表面处理、表面清洗等原理和应用案例进行详细分享,并对激光在塑料加工中应用趋势作些预料。 展开更多
关键词 激光技术 3D打印 切割焊接 表面处理 应用案例
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BIM技术在建筑节能优化中的角色与价值
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作者 王红兵 《上海建材》 2024年第2期18-22,共5页
首先,从提高设计效率和质量、降低能耗、提升环境质量和人体舒适度、加强团队协作和信息共享、推动行业信息化转型等方面,详细阐述了建筑信息模型(BIM)在建筑节能优化中的作用;其次,分析了BIM在建筑节能优化中面临的挑战,包括技术成熟... 首先,从提高设计效率和质量、降低能耗、提升环境质量和人体舒适度、加强团队协作和信息共享、推动行业信息化转型等方面,详细阐述了建筑信息模型(BIM)在建筑节能优化中的作用;其次,分析了BIM在建筑节能优化中面临的挑战,包括技术成熟度、人员技能、数据安全、跨行业协作和法规政策等;最后,对BIM技术的未来发展趋势进行了展望。 展开更多
关键词 BIM技术 建筑节能 绿色建筑 碳减排
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