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Study on the Mathematical Model of Technology Diffusion in Technical Economic System
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作者 Jun Li Li Zhang 《数学计算(中英文版)》 2023年第1期1-6,共6页
In the technical and economic system,there is a certain interaction between various technologies,mainly in the form of technology diffusion.By constructing the mathematical model of technology diffusion,the trend of t... In the technical and economic system,there is a certain interaction between various technologies,mainly in the form of technology diffusion.By constructing the mathematical model of technology diffusion,the trend of technology diffusion can be predicted,the reasonable distribution of science and technology productivity can be realized,and the policy optimization measures can be formulated on the basis of evaluating the existing policies.This paper first points out the basic idea of digital model of technology diffusion,and then focuses on the analysis of various parameters of mathematical model of technology diffusion,and puts forward the application conclusion of mathematical model of technology diffusion,in order to provide reference for relevant industry personnel. 展开更多
关键词 technology and Economic System technology diffusion Digital Model
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Advanced 3D ordered electrodes for PEMFC applications: From structural features and fabrication methods to the controllable design of catalyst layers
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作者 Kaili Wang Tingting Zhou +4 位作者 Zhen Cao Zhimin Yuan Hongyan He Maohong Fan Zaiyong Jiang 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第9期1336-1365,共30页
The catalyst layers(CLs) electrode is the key component of the membrane electrode assembly(MEA) in proton exchange membrane fuel cells(PEMFCs). Conventional electrodes for PEMFCs are composed of carbon-supported, iono... The catalyst layers(CLs) electrode is the key component of the membrane electrode assembly(MEA) in proton exchange membrane fuel cells(PEMFCs). Conventional electrodes for PEMFCs are composed of carbon-supported, ionomer, and Pt nanoparticles, all immersed together and sprayed with a micron-level thickness of CLs. They have a performance trade-off where increasing the Pt loading leads to higher performance of abundant triple-phase boundary areas but increases the electrode cost. Major challenges must be overcome before realizing its wide commercialization. Literature research revealed that it is impossible to achieve performance and durability targets with only high-performance catalysts, so the controllable design of CLs architecture in MEAs for PEMFCs must now be the top priority to meet industry goals. From this perspective, a 3D ordered electrode circumvents this issue with a support-free architecture and ultrathin thickness while reducing noble metal Pt loadings. Herein, we discuss the motivation in-depth and summarize the necessary CLs structural features for designing ultralow Pt loading electrodes. Critical issues that remain in progress for 3D ordered CLs must be studied and characterized. Furthermore, approaches for 3D ordered CLs architecture electrode development, involving material design, structure optimization, preparation technology, and characterization techniques, are summarized and are expected to be next-generation CLs for PEMFCs. Finally, the review concludes with perspectives on possible research directions of CL architecture to address the significant challenges in the future. 展开更多
关键词 PEMFC 3D ordered electrode Structural features Preparation technology Ultralow pt loading
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Diffusion and adoption of environmentally sound technology in China cement industry 被引量:1
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作者 Cai Ning Economics Department, Zhejiang University, Hangzhou 310027, China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1997年第3期68-75,共8页
From rapid growth of cement industry in China there is serious pollution of powdered dust. After general analysis on factors influencing adoption of environmentally sound technology(EST) as well as economic benefit ... From rapid growth of cement industry in China there is serious pollution of powdered dust. After general analysis on factors influencing adoption of environmentally sound technology(EST) as well as economic benefit from adoption of dust removing technology and capital ability of cement firms to invest, the conclusion that the obstacles to EST in China cement sector are different from ones in other sectors was drawn. And then, hindrances to diffusion and adoption of EST in China cement were discussion by empirical study. 展开更多
关键词 dust removing technology diffusion hindrance cement industry.
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In vitro evaluation of transdermal permeation effects of Fu’s cupping therapy via six diffusion kinetics models 被引量:1
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作者 Wei-Jie Xie Yu-Mei Wu +4 位作者 Shuai-Shuai Chen Jian Xu Fang-Fang Yang Yong-Ping Zhang Xiao-Bo Sun 《Traditional Medicine Research》 2019年第1期42-53,共12页
In this study,six kinetics models of indomethacin hydrophilic gel patch transdermal in vitro release was established,including zero-level,first-order,Higuchi-level,Ritger-Peppas,Weibull and Hixcon-Crowell dynamic equa... In this study,six kinetics models of indomethacin hydrophilic gel patch transdermal in vitro release was established,including zero-level,first-order,Higuchi-level,Ritger-Peppas,Weibull and Hixcon-Crowell dynamic equations.The chemical permeation enhancers,including 3%and 5%Azone,and iontophoresis were used as the control.Transdermal diffusion tests were performed in vitro and indomethacin was quantified by high performance liquid chromatography system.The transdermal parameter of the Higuchi and Weibull dynamic equations,indicated that Fu’s cupping therapy(FCT)could significantly improve Higuchi and Weibull kinetic parameters in vitro transdermal,increased transdermal rate and permeability coefficient,reduced lagging time.Additionally,statistical analysis speculated the skin barrier function could be restored after 46 h treatment.Hence,as a new physical transdermal drug delivery technology,transdermal permeation effects produced by FCT are obvious,which has the characteristics of traditional Chinese medicine and has important clinical application value. 展开更多
关键词 Indomethacin diffusion kinetics models Fu’s cupping therapy Transdermal permeation technology Chemical penetration enhancers Traditional Chinese medicine
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Molecular dynamics simulation of the interaction of ethanol-water mixture with a Pt surface
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作者 Kholmirzo Kholmurodov Ermuhammad Dushanov +5 位作者 Kenji Yasuoka Hagar Khalil Ahmed Galal Sameh Ahmed Nasser Sweilam Hatem Moharram 《Natural Science》 2011年第12期1011-1021,共11页
An analysis of the molecular dynamics of ethanol solvated by water molecules in the absence and presence of a Pt surface has been performed using DL_POLY_2.19 code. The structure and diffusion properties of an ethanol... An analysis of the molecular dynamics of ethanol solvated by water molecules in the absence and presence of a Pt surface has been performed using DL_POLY_2.19 code. The structure and diffusion properties of an ethanol–water system have been studied at various temperatures from 250 to 600 K. We have measured the self-diffusion coefficients of the 50:50% ethanol–water solution;in the absence of a Pt surface our results show an excellent agreement–within an error of 7.4% – with the experimental data. An increase in the self-diffusion coefficients with the inclusion of a Pt surface has been observed. The estimation of the diffusion coefficients of both water and ethanol in the presence of a Pt surface shows that they obey the Arrhenius equation;the calculated activation energies of diffusion of ethanol and water are 2.47 and 2.98 Kcal/mole, respectively. The radial distribution function graphs and density profiles have been built;their correlations with the self-diffusion coefficients of both ethanol and water molecules are also illustrated. 展开更多
关键词 Molecular Dynamics Simulations Ethanol MOLECULE Water Active Solvent diffusion Coefficient pt SURFACE RDF Graphs
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The Application of Ecological Elements of Digital Technology in Construction Industry
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作者 Jie Sun 《Open Journal of Civil Engineering》 2021年第1期14-27,共14页
The application of digital technology in the field of construction is still in its infancy, and the existing concrete framework of digital technology application in the construction industry and the study of applied e... The application of digital technology in the field of construction is still in its infancy, and the existing concrete framework of digital technology application in the construction industry and the study of applied ecological elements are not enough. The ecological elements of digital technology application in the construction industry are important factors that promote the healthy op</span><span style="font-family:Verdana;">eration of the entire digital technology application ecosystem. </span><span style="font-family:Verdana;">Using grounded theory, we compiled the data of 33 researchers who participated in </span><span style="font-family:Verdana;">semi-structured interviews, and obtained 4 main categories and 9</span><span style="font-family:Verdana;"> sub-categories of ecological elements of digital technology application in the construction industry. Among them, the digital technology application mechanism is the core category of ecological application elements. We also used the Bass model to analyze the application trend of digital technology in the construction industry. </span><span style="font-family:Verdana;">In 2040, the number of construction companies applying digital</span><span style="font-family:Verdana;"> technology will reach 98.66% of the maximum market potential. 展开更多
关键词 Digital technology in Construction Industry Ecological Elements technology diffusion Grounded theory Bass Model
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Determination of isothermal section of Ni-Pt-Ta ternary system at 1173K
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作者 王日初 柳春雷 金展鹏 《中国有色金属学会会刊:英文版》 EI CSCD 2002年第4期759-761,共3页
The isothermal section of the Ni Pt Ta ternary system at 1?173?K was determined by means of the diffusion triple technology and the electron microprobe analysis. The phase relations in this system were studied. Linear... The isothermal section of the Ni Pt Ta ternary system at 1?173?K was determined by means of the diffusion triple technology and the electron microprobe analysis. The phase relations in this system were studied. Linear compound (Ni, Pt) 3Ta with small solubility forming between Ni 3Ta and Pt 3Ta was identified. Four binary compounds, i.e. Pt 2Ta, Ni 2Ta, NiTa and NiTa 2, and four three phase fields, i.e. Pt 2Ta+(Ta)+NiTa 2, Pt 2Ta+NiTa 2+NiTa, Pt 2Ta+(Ni, PT) 3Ta+NiTa and (Ni, Pt) 3Ta+NiTa+Ni 2Ta, were also identified. 展开更多
关键词 等温截面 相图 Ni-pt-Ta三元系 相平衡 扩散 测定
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Influence of University Factors on the Students' Acceptance of Internet Based Learning Tools in Higher Education
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作者 Jimmy Macharia Emanuel Nyakwende 《通讯和计算机(中英文版)》 2010年第10期72-82,共11页
关键词 学习工具 影响因素 大学 学生 高等教育 网络学习 基础 信息通信技术
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Effect of Technology Support for Social Network on Agricultural Technology Diffusion 被引量:1
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作者 旷浩源 应若平 《Agricultural Science & Technology》 CAS 2012年第1期98-102,共5页
[Objective] To analyze the key factor in agricultural technology diffusion- technology support, and to explore the method to quicken the diffusion of agricultural technology. [Method] The technology acquisition advant... [Objective] To analyze the key factor in agricultural technology diffusion- technology support, and to explore the method to quicken the diffusion of agricultural technology. [Method] The technology acquisition advantage of social network was il- lustrated by summarizing the status and characteristics of agricultural technology and technology supporting types in the process of agriculture technology diffusion. [Result] The multi-layer, complex, persistence, systematization features of agricultural technol- ogy require support and help of technology from surrounding social network to ulti- mately internalize the technology. [Conclusion] Using social networks for the technol- ogy support will be a powerful supplement to the system of agricultural technology diffusion. 展开更多
关键词 Agricultural technology diffusion Social network technology support
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Identification of digital technologies and digitalisation trends in the mining industry 被引量:10
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作者 Lars Barnewold Bernd G.Lottermoser 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2020年第6期747-757,共11页
Digitalisation in mining refers to the use of computerised or digital devices or systems and digitised data that are to reduce costs,improve business productivity,and transform mining practices.However,it remains incr... Digitalisation in mining refers to the use of computerised or digital devices or systems and digitised data that are to reduce costs,improve business productivity,and transform mining practices.However,it remains increasingly difficult for mining companies to decide which digital technologies are most relevant to their needs and individual mines.This paper provides an overview of digital technologies currently relevant to mining companies as presented and discussed by mining journals,the media and insight reports of leading consultancy agencies.Relevant technologies were systematically identified using text-mining techniques,and network analyses established the relations between significant technologies.Results demonstrated that currently 107 different digital technologies are pursued in the mining sector.Also,an analysis of the actual implementation of digital technologies in 158 active surface and underground mines reveals a limited uptake of digital technologies in general and that the uptake increases with the run-of-mine production.Large-scale mining operations appear to select and apply digital technologies suitable to their needs,whereas operations with lower production rates do not implement the currently available digital technologies to the same extent.These minor producers may require other digital transformation solutions tailored to their capabilities and needs and applicable to their scale of operations. 展开更多
关键词 diffusion of digital technologies AUTOMATION Internet of things Big data Machine learning Artificial intelligence
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Spatial Heterogeneity of Agricultural Science and Technology Parks Technology Diffusion: A Case Study of Yangling ASTP 被引量:2
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作者 WANG Zhao LIU Jianhong +2 位作者 LI Tongsheng REN Wanying RUI Yang 《Chinese Geographical Science》 SCIE CSCD 2021年第4期629-645,共17页
Agricultural science and technology parks(ASTPs) represent an important growth pole in China’s agricultural modernization.Clarifying their diffusion laws can optimize the technological diffusion process and improve i... Agricultural science and technology parks(ASTPs) represent an important growth pole in China’s agricultural modernization.Clarifying their diffusion laws can optimize the technological diffusion process and improve its efficiency. Our study uses disaggregated spatial information in its model to analyze ASTP technology diffusion in a heterogeneous space. We constructed a comprehensive index system to evaluate the diffusion environmental quality and introduced the heterogeneous diffusion equation to calculate the technological diffusion probability. We applied this framework to a real-world scenario: the apple planting technology diffusion of the Yangling ASTP in the Loess Plateau, China. The results indicated: (1)the technological diffusion environment of the Loess Plateau advantageous apple producing area showed strong spatial heterogeneity caused by climate, topography, and external transportation links.(2) Under the combined effects of distance and spatial heterogeneity, the spatial diffusion pattern of the Yangling ASTP apple technology was expansion diffusion supplemented by hierarchical diffusion and banded diffusion, and (3) ASTP technology diffusion showed a strong distance attenuation effect, and the frictional effect of distance can be decreased by improving the diffusion environmental quality. These laws can promote regional balanced ASTP-driven development. 展开更多
关键词 agricultural science and technology park(ASTP) heterogeneous environments diffusion environment diffusion probability heterogeneous space diffusion equation
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Visible light-enhanced photothermal CO2 hydrogenation over Pt/Al2O3 catalyst 被引量:5
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作者 Ziyan Zhao Dmitry EDoronkin +3 位作者 Yinghao Ye Jan-Dierk Grunwaldt Zeai Huang Ying Zhou 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第2期286-293,共8页
Light illumination has been widely used to promote activity and selectivity of traditional thermal catalysts. Nevertheless, the role of light irradiation during catalytic reactions is not well understood. In this work... Light illumination has been widely used to promote activity and selectivity of traditional thermal catalysts. Nevertheless, the role of light irradiation during catalytic reactions is not well understood. In this work, Pt/Al2 O3 prepared by wet impregnation was used for photothermal CO2 hydrogenation, and it showed a photothermal effect. Hence, operando diffuse reflectance infrared Fourier-transform spectroscopy and density functional theory calculations were conducted on Pt/Al2 O3 to gain insights into the reaction mechanism. The results indicated that CO desorption from Pt sites including step sites(Ptstep) or/and terrace site(Ptterrace) is an important step during CO2 hydrogenation to free the active Pt sites. Notably, visible light illumination and temperature affected the CO desorption in different ways. The calculated adsorption energy of CO on Ptstep and Ptterrace sites was-1.24 and-1.43 e V, respectively. Hence, CO is more strongly bound to the Ptstep sites. During heating in the dark, CO preferentially desorbs from the Ptterrace site. However, the additional light irradiation facilitates transfer of CO from the Ptstep to Ptterrace sites and its subsequent desorption from the Ptterrace sites, thus promoting the CO2 hydrogenation. 展开更多
关键词 CO2 hydrogenation Photothermal catalysis pt/AL2O3 Operando diffuse reflectance infrared Fourier transform spectroscopy Density functional theory
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Dynamic models of technology management capability development based on knowledge diffusion 被引量:1
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作者 Weiwei Wu Bo Yu Jian Wang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第2期228-237,共10页
Technology management is recognized as a key for organizations to achieve competitiveness. How to promote an organization’s technology management capability is of great significance in creating efficiencies and achie... Technology management is recognized as a key for organizations to achieve competitiveness. How to promote an organization’s technology management capability is of great significance in creating efficiencies and achieving a competitive edge. The knowledge essence of technology management capability is introduced and then the correlation between knowledge diffusion and the development of technology management capability is discussed. Further, the basic and extended dynamic models of the development of technology management capability are constructed, and is applied into an enterprise. The results show that the dynamic models can well explain how the knowledge improves the development of technology management capability, and they can be used as an useful tool by an enterprise to promote technology management capability. Finally, the managerial implications of the models are discussed. 展开更多
关键词 technology management knowledge diffusion dynamic model.
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A KIND OF PAPR REDUCTION METHOD BASED ON PRUNING WPM AND PTS TECHNOLOGY
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作者 Huang Xian Tan Gewei +2 位作者 Xu Qingyong Xu Ning Wang Shuangxi 《Journal of Electronics(China)》 2013年第3期261-267,共7页
Wavelet packet multicarrier system gains widespread concern because of its better resistance performance to Inter-Symbol Interference (ISI) and Inter-Carrier Interference (ICI), as well as the higher spectrum efficien... Wavelet packet multicarrier system gains widespread concern because of its better resistance performance to Inter-Symbol Interference (ISI) and Inter-Carrier Interference (ICI), as well as the higher spectrum efficiency. However, multicarrier system has a high Peak to Average Power Ratio (PAPR), which will lead to many problems such as lower system performance. In order to solve the problem, a kind of PAPR reduction method based on pruning Wavelet Packet Modulation (WPM) and Partial Transmit Sequences (PTS) technology is proposed in this paper, through proper pruning of the full-tree structure of wavelet packet modulation in the PTS technology to reduce the number of nodes in the system, and finally improve the reduction effect of PAPR. Simulation results show that when Complementary Cumulative Distribution Function (CCDF) is 10 -3 , PTS based on pruning WPM compared with PTS technique and pruning technique has improved about 1 dB and 1.5 dB, which will not affect the system's Bit Error Rate (BER) performance in the wavelet packet multicarrier system. 展开更多
关键词 Multicarrier modulation Wavelet packet Pruning wavelet packet Peak to Average Power Ratio (PAPR) Partial Transmit Sequences (ptS) technology
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A generalized formula for two-dimensional diffusion of CO in graphene nanoslits with different Pt loadings
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作者 Chenglong Qiu Yinbin Wang +5 位作者 Yuejin Li Xiang Sun Guilin Zhuang Zihao Yao Shengwei Deng Jianguo Wang 《Green Energy & Environment》 SCIE CSCD 2020年第3期322-332,共11页
Catalytic performance of supported metal catalysts not only depends on the reactivity of metal,but also the adsorption and diffusion properties of gas molecules which are usually affected by many factors,such as tempe... Catalytic performance of supported metal catalysts not only depends on the reactivity of metal,but also the adsorption and diffusion properties of gas molecules which are usually affected by many factors,such as temperature,pressure,properties of metal clusters and substrates,etc.To explore the impact of each of these macroscopic factors,we simulated the movement of CO molecules confined in graphene nanoslits with or without supported Pt nanoparticles.The results of molecular dynamics simulations show that the diffusion of gas molecules is accelerated with high temperature,low pressure or low surface-atom number of supported metals.Notably,the supported metal nanoparticles greatly affect the gas diffusion due to the adsorption of gas molecules.Furthermore,to bridge a quantitative relationship between microscopic simulation and macroscopic properties,a generalized formula is derived from the simulation data to calculate the diffusion coefficient.This work helps to advise the diffusion modulation of gas molecules via structural design of catalysts and regulation of reaction conditions. 展开更多
关键词 Gas diffusion Graphene nanoslits Supported pt nanoparticles Molecular dynamics simulation
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An Investigation on Telecommunication Staff's Acceptance of E-Learning Technology
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作者 Yu Ya-Chu Huang Kuo-Hung 《Journal of Modern Accounting and Auditing》 2011年第10期1150-1157,共8页
As the information on telecommunication products updates rapidly, using E-learning in staff training becomes an edge for company operation. However, previous studies showed that staff's attitude toward E-learning sig... As the information on telecommunication products updates rapidly, using E-learning in staff training becomes an edge for company operation. However, previous studies showed that staff's attitude toward E-learning significantly affected the outcomes of training. The purpose of this study is to investigate the acceptance of E-learning in a telecommunication company. The researchers adopted the technology acceptance model (TAM) and diffusion of innovation theory to evaluate the perceived usefulness and perceived ease of use on E-learning, in addition to employees' self-directed learning motivation, attitude toward computers, and organizational influence. We randomly chose 571 employees of the telecommunication entrepreneur at the Taichung office in Taiwan to participate in this survey. The result showed that employees' background factors such as age, job position, marital status, education level and the scale of job unit had the significant impact on behavioral intention to use E-learning. Employees' self-directed learning, attitude toward computers, and organizational influence respectively also had positive effects on perceived usefulness of E-learning and perceived ease of use of E-learning. Furthermore, employees' perceived usefulness of E-learning and perceived ease of use of E-learning also had a positive effect on behavioral intention to use E-learning systems. 展开更多
关键词 diffusion of innovation theory E-LEARNING self-directed learning the technology acceptance model
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Open Innovation and New Mechanism of Market-Based Technology Diffusion from MNCs
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作者 Zheng Feihu Cai Hongbo Zhong Xin 《China Economist》 2020年第6期84-100,共17页
The international community has blamed developing countries for the lack of intellectual property rights(IPR)protection-not least the“forced technology transfers”-in attracting foreign direct investment(FDI).This pa... The international community has blamed developing countries for the lack of intellectual property rights(IPR)protection-not least the“forced technology transfers”-in attracting foreign direct investment(FDI).This paper employs the largesample contract data of multinational companies’(MNCs)IT R&D transactions in China to discuss this controversy from a unique perspective of MNCs in the role of contractors.Our findings suggest that MNCs initially guarded their know-how before the 2000s under closed innovation,but have started to take the initiative to transfer technology to local partners as open innovation held sway.China’s structured market entities and huge demand for technology transactions have served as key drivers for MNCs to transfer technology,which has been further boosted by the new business model of open innovation.This paper’s empirical analysis not only helps unravel the“black box”of technology transfers by MNCs,but reveals how late-moving developing countries may make better use of FDI referencing China’s experience on the three dimensions of market opportunities,structured entities,and economies of scale. 展开更多
关键词 open innovation foreign direct investment(FDI) market-based technology diffusion initiative to match between supply and demand
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Technology Sub-diffusions:Consumptive Motivations for Mobile Phone Calls and Digital Services
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作者 Chih-Peng Chu 《China Communications》 SCIE CSCD 2008年第4期120-128,共9页
Digital services interfaced with mobile phone lines are gradually being regarded as a core product in this modern age due to the high transmission speed of mobile technology.The research in this paper is based on the ... Digital services interfaced with mobile phone lines are gradually being regarded as a core product in this modern age due to the high transmission speed of mobile technology.The research in this paper is based on the concept of product inter-dependence and actively explores the different consumptive motivations between the consumers' behavior of phone-call users and those who use digital services.This study also attempts to use a modifi ed diffusion model to estimate the consumers' collective behavior with a longitudinal approach.In this study,it can be inferred that psychological consumer motivations should dominate marketing policies.Thus,it was found that digital service users have more self-motivation and autonomy when adopting a new product because they have significantly higher innovative at-tributes than the segment of phone-call users.With these findings,we claim that we have discovered an unprec-edented concept for marketing managers who welcome the challenges of mobile digital services in the future. 展开更多
关键词 Inter-dependent products technology dif-fusion Mobile telecommunication DIGITAL SERVICES Consumptive MOTIVATIONS
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光OFDM系统中基于PTS算法对峰均比抑制技术的分析 被引量:1
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作者 袁建国 梁梦琪 +1 位作者 王竞鑫 王永 《半导体光电》 CAS 北大核心 2016年第3期408-412,共5页
针对光正交频分复用(OFDM)系统中峰值平均功率比(PAPR)较高的缺点,重点研究了基于部分序列传输法(PTS)的峰均比抑制技术,提出一种改进的加强迭代PTS搜索技术(EIA-PTS),该技术能够降低原PTS的计算复杂度。仿真表明:原PTS方法随着相应参... 针对光正交频分复用(OFDM)系统中峰值平均功率比(PAPR)较高的缺点,重点研究了基于部分序列传输法(PTS)的峰均比抑制技术,提出一种改进的加强迭代PTS搜索技术(EIA-PTS),该技术能够降低原PTS的计算复杂度。仿真表明:原PTS方法随着相应参数的增加,迭代次数呈指数型增长,而EIA-PTS技术的迭代次数基本保持平稳且低于原PTS方法。在此基础上,又将EIA-PTS与削波(Clipping)技术相结合,提出了峰均比EIA-PTS-Clipping联合抑制技术。与EIA-PTS技术相比,该技术进一步提升了系统PAPR的抑制性能,能在系统误码率(BER)性能与PAPR抑制效果之间取得更好的折衷,具有较高的利用价值。 展开更多
关键词 部分序列传输 峰均比 削波 抑制技术 ofDM系统
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Diffusion of Acetic Acid Across Oil/Water Interface in Emulsification-Internal Gelation Process for Preparation of Alginate Gel Beads 被引量:1
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作者 LIU Xiu-dong YU Wei-ting +2 位作者 LIN Jun-zhang MA Xiao-jun YUAN Quan 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2007年第5期579-584,共6页
Alginate has been widely used in cell microencapsulation and drug delivery systems in the form of gel beads or microcapsules.Although an alternative novel emulsification-internal gelation technology has been establish... Alginate has been widely used in cell microencapsulation and drug delivery systems in the form of gel beads or microcapsules.Although an alternative novel emulsification-internal gelation technology has been established and both the properties and the potential applications of the beads in drug delivery systems have been studied,the mechanism has not been well understood compared with the traditional droplet method(external gelation technology).On the basis of our previous knowledge that the novel technology is composed of complicatedly consecutive processes with multistep diffusion and reaction,and the diffusion of acetic acid across oil/water interface being the prerequisite that determines the occurrence and rate for the reactions and the structures and properties of final produced gel beads,a special emphasis was placed on the diffusion process.With the aid of diffusion modeling and simple experimental design,the diffusion rate constant and diffusion coefficient of acetic acid across oil/water interface were determined to be in the orders of magnitude of 10-6 and 10-16,respectively.This knowledge will be of particular importance in understanding and interpreting the formation,structure of the gel beads and the relationship between the structure and properties and guiding the preparation and quality control of the gel beads. 展开更多
关键词 Emulsification-internal gelation technology ALGINATE Gel bead diffusion rate constant diffusion coefficient
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