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Optimization Strategies of Na_(3)V_(2)(PO_(4))_(3) Cathode Materials for Sodium‑Ion Batteries
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作者 Jiawen Hu Xinwei Li +4 位作者 Qianqian Liang Li Xu Changsheng Ding Yu Liu Yanfeng Gao 《Nano-Micro Letters》 SCIE EI CAS 2025年第2期204-251,共48页
Na_(3)V_(2)(PO_(4))_(3)(NVP)has garnered great attentions as a prospective cathode material for sodium-ion batteries(SIBs)by virtue of its decent theoretical capacity,superior ion conductivity and high structural stab... Na_(3)V_(2)(PO_(4))_(3)(NVP)has garnered great attentions as a prospective cathode material for sodium-ion batteries(SIBs)by virtue of its decent theoretical capacity,superior ion conductivity and high structural stability.However,the inherently poor electronic conductivity and sluggish sodium-ion diffusion kinetics of NVP material give rise to inferior rate performance and unsatisfactory energy density,which strictly confine its further application in SIBs.Thus,it is of significance to boost the sodium storage performance of NVP cathode material.Up to now,many methods have been developed to optimize the electrochemical performance of NVP cathode material.In this review,the latest advances in optimization strategies for improving the electrochemical performance of NVP cathode material are well summarized and discussed,including carbon coating or modification,foreign-ion doping or substitution and nanostructure and morphology design.The foreign-ion doping or substitution is highlighted,involving Na,V,and PO_(4)^(3−)sites,which include single-site doping,multiple-site doping,single-ion doping,multiple-ion doping and so on.Furthermore,the challenges and prospects of high-performance NVP cathode material are also put forward.It is believed that this review can provide a useful reference for designing and developing high-performance NVP cathode material toward the large-scale application in SIBs. 展开更多
关键词 Sodium-ion batteries Na_(3)V_(2)(PO_(4))_(3) Cathode materials Electrochemical performance Optimization strategies
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Synthesis and modification strategies of g-C_(3)N_(4) nanosheets for photocatalytic applications 被引量:5
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作者 Long Chen Michael A.Maigbay +1 位作者 Miao Li Xiaoqing Qiu 《Advanced Powder Materials》 2024年第1期49-79,共31页
Graphitic carbon nitride nanosheets(CNNs)become the most promising member in the carbon nitride family benefitted from their two-dimensional structural features.Recently,great endeavors have been made in the synthesis... Graphitic carbon nitride nanosheets(CNNs)become the most promising member in the carbon nitride family benefitted from their two-dimensional structural features.Recently,great endeavors have been made in the synthesis and modification of CNNs to improve their photocatalytic properties,and many exciting progresses have been gained.In order to elucidate the fundamentals of CNNs based catalysts and provide the insights into rational design of photocatalysis system,we describe recent progress made in CNNs preparation strategies and their applications in this review.Firstly,the physicochemical properties of CNNs are briefly introduced.Secondly,the synthesis approaches of CNNs are reviewed,including top-down stripping strategies(thermal,gas,liquid,and composite stripping)and bottom-up precursor molecules design strategies(solvothermal,template,and supramolecular self-assembly method).Subsequently,the modification strategies based on CNNs in recent years are discussed,including crystal structure design,doping,surface functionalization,constructing 2D heterojunction,and anchoring single-atom.Then the multifunctional applications of g-C_(3)N_(4) nanosheet based materials in photocatalysis including H_(2) evolution,O_(2) evolution,overall water splitting,H_(2)O_(2) production,CO_(2) reduction,N_(2) fixation,pollutant removal,organic synthesis,and sensing are highlighted.Finally,the opportunities and challenges for the development of high-performance CNNs photocatalytic systems are also prospected. 展开更多
关键词 G-C_(3)N_(4) NANOSHEETS Synthesis strategies Modified strategies Photocatalytic applications
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Marketing Strategy Analysis of Migu Video App Based on 4I Theory
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作者 Binli Zhang 《Proceedings of Business and Economic Studies》 2024年第3期1-5,共5页
With the increasing maturity of 5G technology and the comprehensive development of video apps on the Internet,the landscape of video app downloads shows that Migu Video lags behind giants like iQiyi,Tencent Video,Youk... With the increasing maturity of 5G technology and the comprehensive development of video apps on the Internet,the landscape of video app downloads shows that Migu Video lags behind giants like iQiyi,Tencent Video,Youku,and Mango TV.However,during the Tokyo Olympics and the Beijing Winter Olympics,Migu Video’s focus on sports coverage and commentary led to increased public use and app downloads.This study analyzes the marketing status and strategy of the Migu Video App.It conducts a detailed analysis using the 4I theory-interest,interaction,individuality,and initiative-and proposes a brand marketing strategy tailored for Migu Video.This aims to provide insights into the marketing strategies of other mobile Internet companies. 展开更多
关键词 Migu Video App 4I theory Marketing strategy
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中国电信应明确4G发展思路 对话Strategy Analytics无线运营商战略高级分析师 杨光 被引量:1
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作者 黄海峰 《通信世界》 2013年第24期26-26,共1页
从竞争角度,中国移动的TD-LTE以试验网名义进行规模部署,在网络覆盖、用户规模和财务状况都占绝对优势,所以这对中国电信4G发展带来巨大挑战。中国4G规模商用临近,三大运营商纷纷表明态度。中国移动规划今年建设20.7万个TD-LTE基站,4G... 从竞争角度,中国移动的TD-LTE以试验网名义进行规模部署,在网络覆盖、用户规模和财务状况都占绝对优势,所以这对中国电信4G发展带来巨大挑战。中国4G规模商用临近,三大运营商纷纷表明态度。中国移动规划今年建设20.7万个TD-LTE基站,4G先行一步。中国电信则在今年加速4G试验网建设进程,起步晚但进展迅速。 展开更多
关键词 无线运营商 中国电信 strategy 4G TD-LTE 对话 级分 中国移动
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Strategy Analytics:4G运营需兼顾综合服务体验及产业良性发展
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作者 赵光磊 《通信世界》 2014年第5期16-16,共1页
随着LTE融合发展成为全球共识,LTE的现网运营已经成为全球运营商的关注焦点,包括LTE品牌打造、资费设置、终端普及等方面成为整个业界最为关注的话题。LTE的产业机遇期已经全面到来,本期《通信世界》专访了Strategy Analytics的两位... 随着LTE融合发展成为全球共识,LTE的现网运营已经成为全球运营商的关注焦点,包括LTE品牌打造、资费设置、终端普及等方面成为整个业界最为关注的话题。LTE的产业机遇期已经全面到来,本期《通信世界》专访了Strategy Analytics的两位分析师,为读者分享LTE的全球运营经验以及如何把握国内市场的发展机遇。 展开更多
关键词 strategy 运营商 良性发展 综合服务 产业 4G LTE 国内市场
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Language learning strategy in helping Chinese EFL university students with CET4 Written Test as a goal
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作者 杨慧 《海外英语》 2014年第8X期91-94,97,共5页
This article discusses the application of theories in the field of learning strategies to ELT classroom in Chinese universities.By reviewing the literature of learning strategies,this article examines the possible con... This article discusses the application of theories in the field of learning strategies to ELT classroom in Chinese universities.By reviewing the literature of learning strategies,this article examines the possible connection between theories and the Chinese ELT classroom in specific,in which it focuses on the requirements of CET 4 examination.By doing so,this article tries to offer some suggestions that could be used in the classroom. 展开更多
关键词 LANGUAGE learning strategy learner autonomy learni
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ZnIn_(2)S_(4)基光催化剂的制备及改性研究进展 被引量:1
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作者 李冠琼 梁海欧 +1 位作者 李春萍 白杰 《材料导报》 EI CAS CSCD 北大核心 2024年第3期7-12,共6页
近年来,硫锌铟(ZnIn_(2)S_(4))作为层状结构的三元金属硫化物,是一种典型的可见光响应光催化剂,由于其无毒,易于合成,具有可调的带隙、较好的物理化学稳定性以及优异的光催化活性等一系列优势,一度被应用于光催化的不同领域。本文着眼于... 近年来,硫锌铟(ZnIn_(2)S_(4))作为层状结构的三元金属硫化物,是一种典型的可见光响应光催化剂,由于其无毒,易于合成,具有可调的带隙、较好的物理化学稳定性以及优异的光催化活性等一系列优势,一度被应用于光催化的不同领域。本文着眼于ZnIn_(2)S_(4)的晶体结构和生长机理,综述了ZnIn_(2)S_(4)常用的制备工艺。此外,基于ZnIn_(2)S_(4)存在的弊端,总结了提高ZnIn_(2)S_(4)光催化性能的各种调控策略,包括形貌和结构工程、空位工程、掺杂工程以及半导体异质结的构建,并深入分析了不同调控方式对ZnIn_(2)S_(4)光催化性能增强的内在原因。最后,提出ZnIn_(2)S_(4)基光催化剂目前面临的挑战和未来的应用前景。 展开更多
关键词 ZnIn_(2)S_(4) 制备工艺 改性策略 光催化
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Engineering g-C_(3)N_(4)based materials for advanced photocatalysis:Recent advances 被引量:1
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作者 Xin-Lian Song Lei Chen +2 位作者 Li-Jiao Gao Jin-Tao Ren Zhong-Yong Yuan 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第2期166-197,共32页
Photocatalysis driven by abundant yet intermittent solar energy has considerable potential in renewable energy generation and environmental remediation.The outstanding electronic structure and physicochemical properti... Photocatalysis driven by abundant yet intermittent solar energy has considerable potential in renewable energy generation and environmental remediation.The outstanding electronic structure and physicochemical properties of graphitic carbon nitride(g-C_(3)N_(4)),together with unique metal-free characteristic,make them ideal candidates for advanced photocatalysts construction.This review summarizes the up-to-date advances on g-C_(3)N_(4)based photocatalysts from ingenious-design strategies and diversified photocatalytic applications.Notably,the advantages,fabrication methods and limitations of each design strategy are systemically analyzed.In order to deeply comprehend the inner connection of theory–structure–performance upon g-C_(3)N_(4)based photocatalysts,structure/composition designs,corresponding photocatalytic activities and reaction mechanisms are jointly discussed,associated with introducing their photocatalytic applications toward water splitting,carbon dioxide/nitrogen reduction and pollutants degradation,etc.Finally,the current challenges and future perspectives for g-C_(3)N_(4)based materials for photocatalysis are briefly proposed.These design strategies and limitations are also instructive for constructing g-C_(3)N_(4) based materials in other energy and environment-related applications. 展开更多
关键词 Graphitic carbon nitride g-C_(3)N_(4) Design strategies PHOTOCATALYSIS PHOTOCATALYSTS Reaction mechanism
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Glypican 4 down-regulation in pluripotent stem cells as a potential strategy to improve differentiation and to impair tumorigenicity of cell transplants
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作者 Rosanna Dono 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第10期1576-1577,共2页
Recent advances in stem cell technologies have opened new avenues for the treatment of a number of diseases still lacking effective therapeutic options.Cell transplantation has emerged as among the most promising clin... Recent advances in stem cell technologies have opened new avenues for the treatment of a number of diseases still lacking effective therapeutic options.Cell transplantation has emerged as among the most promising clinical intervention for disorders such as injuries,diabetes,liver diseases, neurodegeneration and heart failure (Lee et al., 2013; Forbes and Rosenthal, 2014; Tabar and Studer, 2014). 展开更多
关键词 PSCs CELL Glypican 4 down-regulation in pluripotent stem cells as a potential strategy to improve differentiation and to impair tumorigenicity of cell transplants stem
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The Development Strategy Based on 4Ps Theory of Continuing Education in Universities
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作者 TANG Yaner ZHU Caiju 《International English Education Research》 2018年第2期80-82,共3页
From the perspective of marketing theory and the premise of SWOT theory analysis,this paper puts forward the basic strategies of developing continuing education based on 4Ps theory in universities.Combined with the ed... From the perspective of marketing theory and the premise of SWOT theory analysis,this paper puts forward the basic strategies of developing continuing education based on 4Ps theory in universities.Combined with the educational products in the field of management and public administration in the market economy,this paper analyzes the strengths,weaknesses,opportunities and threats in the development of continuing education in universities.From the four aspects of product,price,place and promotion,we summarize the concrete measure which may provide the reference to develop continuing education. 展开更多
关键词 SWOT Analysis 4Ps Theory Continuing Education strategy
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Strategy Analytics:4G会导致现有顶级手机芯片供应商的消亡吗?
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《通信世界》 2013年第25期5-5,共1页
近日,英特尔宣布发布一款多模LTE芯片,随着LTE终端规模的继续增长,看来在蜂窝无线芯片收入方面高通和英特尔将继续保持其前两位的行业地位。
关键词 strategy 手机芯片 供应商 消亡 4G 无线芯片 LTE 英特尔
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Porous high-entropy rare-earth phosphate(REPO_(4),RE=La,Sm,Eu,Ce,Pr and Gd)ceramics with excellent thermal insulation performance via pore structure tailoring 被引量:1
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作者 Peixiong Zhang Enhui Wang +3 位作者 Jingjing Liu Tao Yang Hailong Wang Xinmei Hou 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第7期1651-1658,共8页
Thermal insulation materials play an increasingly important role in protecting mechanical parts functioning at high temperatures.In this study,a new porous high-entropy(La_(1/6)Ce_(1/6)Pr_(1/6)Sm_(1/6)Eu_(1/6)Gd_(1/6)... Thermal insulation materials play an increasingly important role in protecting mechanical parts functioning at high temperatures.In this study,a new porous high-entropy(La_(1/6)Ce_(1/6)Pr_(1/6)Sm_(1/6)Eu_(1/6)Gd_(1/6))PO_(4)(HE(6RE_(1/6))PO_(4))ceramics was prepared by combining the high-entropy method with the pore-forming agent method and the effect of different starch contents(0–60vol%)on this ceramic properties was systematically investigated.The results show that the porous HE(6RE_(1/6))PO_(4)ceramics with 60vol%starch exhibit the lowest thermal conductivity of 0.061 W·m^(-1)·K^(-1)at room temperature and good pore structure stability with a linear shrinkage of approximately1.67%.Moreover,the effect of large regular spherical pores(>10μm)on its thermal insulation performance was discussed,and an optimal thermal conductivity prediction model was screened.The superior properties of the prepared porous HE(6RE_(1/6))PO_(4)ceramics allow them to be promising insulation materials in the future. 展开更多
关键词 porous high-entropy(La_(1/6)Ce_(1/6)Pr_(1/6)Sm_(1/6)Eu_(1/6)Gd_(1/6))PO_(4) ceramics high-entropy strategy pore-forming agent method thermal insulation material thermal conductivity
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Strategies for Fostering Interaction in Online Classrooms:A Conversation Analysis of Teacher-Student Verbal Interaction in Random Questioning in Pandemic-Initiated Online Teaching
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作者 Ping Zhang 《Journal of Contemporary Educational Research》 2024年第2期98-111,共14页
This paper aims to explore how a veteran teacher organizes online teaching initiated by the pandemic and how she deals with the problems in online teacher-student verbal interaction.By analyzing a corpus of 20 audio-r... This paper aims to explore how a veteran teacher organizes online teaching initiated by the pandemic and how she deals with the problems in online teacher-student verbal interaction.By analyzing a corpus of 20 audio-recorded online lessons between a math teacher and her students during the COVID-19 pandemic from April 11 to May 10,2022,four interactional segments are selected as the focus of the study.The results of the conversation analysis of the segments showed that students’modesty,lack of confidence,lack of ability,and network delay are the main factors affecting online teacher-student interaction.By encouraging students to answer questions,enlightening students to give answers,enriching students’answers,and entertaining the teaching atmosphere(“4Es”strategies),the teacher solved the problems successfully.The findings from this study can provide pedagogical experience and implications for practical teaching. 展开更多
关键词 Online teaching Teacher-student verbal interaction Conversation analysis 4Es”strategies
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4·20芦山地震次生山地灾害与减灾对策 被引量:26
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作者 陈晓清 崔鹏 +2 位作者 游勇 杨宗佶 孔应德 《地学前缘》 EI CAS CSCD 北大核心 2013年第3期29-34,共6页
4.20芦山地震不仅造成了特大地震灾害,同时还诱发大量的次生山地灾害,主要类型包括崩塌、滑坡、滚石、落石、堰塞湖和泥石流等。这些次生灾害不仅造成重大人员伤亡,还阻塞救援道路,延缓了救援进度。地震诱发的大量崩塌、滑坡为泥石流活... 4.20芦山地震不仅造成了特大地震灾害,同时还诱发大量的次生山地灾害,主要类型包括崩塌、滑坡、滚石、落石、堰塞湖和泥石流等。这些次生灾害不仅造成重大人员伤亡,还阻塞救援道路,延缓了救援进度。地震诱发的大量崩塌、滑坡为泥石流活动提供丰富物源,将促进泥石流活跃,在后期暴雨作用下产生严重的泥石流灾害。通过初步分析,提出了地震区山地灾害应急减灾对策,包括应急排查、监测预警、临时安置场所危险性评估、省道210线应急防护;并提出了地震区恢复重建中的减灾对策,包括提高山区城镇的防护能力,加强村寨聚落防灾能力,加强山地灾害监测预警,道路恢复重建中的减灾措施以及加强对流域漂木防治。 展开更多
关键词 芦山地震 次生山地灾害 类型 减灾对策
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儿童2岁时情绪调节策略预测4岁时社会行为 被引量:18
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作者 王莉 陈会昌 陈欣银 《心理学报》 CSSCI CSCD 北大核心 2002年第5期500-504,共5页
考察儿童情绪调节的早期发展对以后社会行为的预测。对 176名儿童进行 2年追踪 :2岁时 ,观察他们在陌生情境和延迟满足情境下的情绪调节策略。 4岁时 ,对他们在陌生同伴情境中的自由游戏活动进行观察 ,评价其社会交往能力和社会退缩性... 考察儿童情绪调节的早期发展对以后社会行为的预测。对 176名儿童进行 2年追踪 :2岁时 ,观察他们在陌生情境和延迟满足情境下的情绪调节策略。 4岁时 ,对他们在陌生同伴情境中的自由游戏活动进行观察 ,评价其社会交往能力和社会退缩性。在儿童完成分车票任务和收拾玩具过程中对其任务坚持性进行评价。通过回归分析我们发现在预测 4岁时社会行为上早期情绪调节策略的主效应显著。这表明 2岁时的情绪调节策略能显著地预测儿童 展开更多
关键词 预测 4 2-4岁儿童 情绪调节策略 社会行为 儿童心理学
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4~6岁儿童分享行为的特点及培养策略 被引量:30
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作者 李幼穗 赵莹 《学前教育研究》 CSSCI 北大核心 2008年第2期39-41,共3页
本研究采用自行设计的实验情境考察天津市某幼儿园4~6岁儿童分享行为的发展特点,结果表明:儿童分享行为随年龄增长而逐渐提高;儿童分享行为没有显著性别差异;儿童对不同分享对象的分享具有显著差异,即通过努力获得的奖品分享最多... 本研究采用自行设计的实验情境考察天津市某幼儿园4~6岁儿童分享行为的发展特点,结果表明:儿童分享行为随年龄增长而逐渐提高;儿童分享行为没有显著性别差异;儿童对不同分享对象的分享具有显著差异,即通过努力获得的奖品分享最多,自带的心爱玩具次之,意外获得的食品分享最少。在此研究结果基础上,本研究提出了儿童分享行为的培养策略,以增进儿童的亲社会行为。 展开更多
关键词 4~6岁儿童 儿童的分享行为 儿童分享行为的培养策略
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基于DM642DSP的MPEG4视频解码算法优化设计 被引量:6
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作者 路锦正 《现代电子技术》 2007年第4期80-82,91,共4页
讨论并实现了基于DSP的MPEG-4视频实时解码算法。首先系统级优化算法,修改适于DSP的数据结构以减小算法对存储器的要求,然后有效分配片上核心内存,针对DSP自身的特点,对EDMA、缓存Cache、线性汇编优化和软件流水及CCS优化工具等方面做... 讨论并实现了基于DSP的MPEG-4视频实时解码算法。首先系统级优化算法,修改适于DSP的数据结构以减小算法对存储器的要求,然后有效分配片上核心内存,针对DSP自身的特点,对EDMA、缓存Cache、线性汇编优化和软件流水及CCS优化工具等方面做专门优化。实验结果证明,该优化算法可实现多路视频图像的实时解码,在码流300 kb/s、CIF分辨率I、BP模式条件下,MPEG-4解码算法速度可达190-200 f/s。 展开更多
关键词 MPEG-4码流 DM642 视频解码 优化策略
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“工业4.0”对经济发展的影响及作用效果——基于德国行业面板数据的实证分析 被引量:4
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作者 李春梅 《科技管理研究》 CSSCI 北大核心 2019年第14期128-136,共9页
以德国为研究对象,首次从实证角度探讨"工业4.0”的技术变革对经济发展的影响。"工业4.0”战略之后,德国经济平稳快速增长;采用德国11个主要行业的面板数据,得到"工业4.0”确实对德国经济有一定影响,信息物理系统中短期... 以德国为研究对象,首次从实证角度探讨"工业4.0”的技术变革对经济发展的影响。"工业4.0”战略之后,德国经济平稳快速增长;采用德国11个主要行业的面板数据,得到"工业4.0”确实对德国经济有一定影响,信息物理系统中短期内物理层的投资会增加经济支出,但网络层和信息层在经济增长中会起到明显的促进作用;2014-2016年,“工业4.0"的时间效应显示德国产业发展出现明显的正向拐点效应。 展开更多
关键词 "工业4.0":德国经济 信息物理系统
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基于工业4.0背景下的工业机器人人才研究分析及解决策略 被引量:9
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作者 彭宽栋 郑龙 +1 位作者 袁俊 罗晓晔 《价值工程》 2017年第24期171-174,共4页
为贯彻落实"中国制造2025"和"互联网+"战略,实现智能制造强国的战略目标,研究分析工业机器人人才需求、健全工业机器人人才培养体系具有重要研究意义。开展了工业4.0战略的深度分析与研究,梳理了工业4.0战略计划与... 为贯彻落实"中国制造2025"和"互联网+"战略,实现智能制造强国的战略目标,研究分析工业机器人人才需求、健全工业机器人人才培养体系具有重要研究意义。开展了工业4.0战略的深度分析与研究,梳理了工业4.0战略计划与工业机器人人才需求的关系,概括了我国工业机器人使用情况,全面分析了我国工业机器人人才需求。研究探索了工业机器人人才培养策略,提出了我国工业机器人人才培养的理念、目标及多角度系统性的培养体系,可展开推广实施。 展开更多
关键词 中国制造2025 工业机器人 工业4.0战略 人才培养体系
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多元化经营的“4W” 被引量:1
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作者 宋伟 《商业研究》 北大核心 2002年第3期39-40,103,共3页
借鉴国内外企业实施多元化经营的成功经验与失败教训,从培养企业核心能力出发,阐述了正确决策和实施多元化经营的几个关键问题,即4W(why、when、where和what),指出正确的多元化经营战略同样有利于企业核心能力的培养。
关键词 多元化经营 4W 多元化战略 企业
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