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The Globalization Practices of Chinese Telecom Operators
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作者 Mo Xinwei Lei Kaizhe 《China Communications》 SCIE CSCD 2008年第1期58-62,共5页
The telecommunications industry is one of the mosttypically globalized industries. Chinese telecom operatorscarry out the globalization practices in theirown ways. This paper sums up the characters of theChinese opera... The telecommunications industry is one of the mosttypically globalized industries. Chinese telecom operatorscarry out the globalization practices in theirown ways. This paper sums up the characters of theChinese operators’ globalization based on a reviewof the recent efforts of Chinese operators. Fourmodes of globalization are pointed out undertakenby Chinese operators: Business Cooperation andAlliance, Branch and Subsidiary Company, Merge& Acquisition and Foreign Direct Investment andExportation of Expertise. And the behaviors of Chineseoperators are categorized into two dimensions:the target customer and the destination region. It isindicated that Chinese operators focus more on thedomestic customers when extending their servicesglobally, especially toward the developed countriesand regions. However, when they intend to graspnew market opportunities, they tend to aim at developingcountries. 展开更多
关键词 GLOBALIZATION Chinese operator MODE
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An elastic-plastic analysis of short-leg shear wall structures during earthquakes 被引量:2
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作者 Ding Jianguo Zhu Ying 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2012年第4期525-540,共16页
Short-leg shear wall structures are a new form of building structure that combine the merits of both frame and shear wall structures. Its architectural features, structure bearing and engineering cost are reasonable. ... Short-leg shear wall structures are a new form of building structure that combine the merits of both frame and shear wall structures. Its architectural features, structure bearing and engineering cost are reasonable. To analyze the elastic-plastic response of a short-leg shear wall structure during an earthquake, this study modified the multiple-vertical-rod element model of the shear wall, considered the shear lag effect and proposed a multiple-vertical-rod element coupling beam model with a new local stiffness domain. Based on the principle of minimum potential energy and the variational principle, the stiffness matrixes of a short-leg shear wall and a coupling beam are derived in this study. Furthermore, the bending shear correlation for the analysis of different parameters to describe the structure, such as the beam height to span ratio, short-leg shear wall height to thickness ratio, and steel ratio are introduced. The results show that the height to span ratio directly affects the structural integrity; and the short-leg shear wall height to thickness ratio should be limited to a range of approximately 6.0 to 7.0. The design of short-leg shear walls should be in accordance with the "strong wall and weak beam" principle. 展开更多
关键词 short-leg shear wall multiple-vertical-rod element model shear lag effect bending shear correlationcoefficient coupling beam stiffness matrix elastic-plastic analysis
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MULTI-CHANNEL TRANSMISSION STRATEGY FOR DYNAMIC SPECTRUM ACCESS
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作者 Wu Yingxiao Yang Zhen 《Journal of Electronics(China)》 2010年第3期345-352,共8页
Cognitive radio is a promising technology that deals with the scarcity of radio spectrum. In this paper, we propose a new multi-channel transmission strategy for dynamic spectrum access in cognitive radio network. Sta... Cognitive radio is a promising technology that deals with the scarcity of radio spectrum. In this paper, we propose a new multi-channel transmission strategy for dynamic spectrum access in cognitive radio network. Starting with the model of spectrum activities, we present the multi-channel transmission strategy which has primary user's protection mechanism to improve the spectrum efficiency and study its performance under perfect and imperfect sensing. Numerical example results reveal that the performance of the proposed strategy has the superiority with respect to capacity performance of cognitive users and the protection of primary users. 展开更多
关键词 Transmission strategy Dynamic spectrum access Multiple channels
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Vertical shaking table tests on the structure with viscoelastic multi-dimensional earthquake isolation and mitigation devices 被引量:4
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作者 XU ZhaoDong SHI BenQiang +1 位作者 WU KeYi ZENG Xiao 《Science China(Technological Sciences)》 SCIE EI CAS 2009年第10期2869-2876,共8页
The viscoelastic multi-dimensional earthquake isolation and mitigation device is a new kind of passive control device, which can perform its "name-giving" task of earthquake isolation and earthquake mitigati... The viscoelastic multi-dimensional earthquake isolation and mitigation device is a new kind of passive control device, which can perform its "name-giving" task of earthquake isolation and earthquake mitigation simultaneously. In order to quantify its vertical earthquake isolation and mitigation effect on structures, firstly, shaking table tests on steel frame structures with and without the devices were carried out; secondly, analysis on dynamic characteristics and dynamic responses of the structures was also performed; furthermore, the finite element analytical results and the experimental results were compared. It can be shown from the analytical and experimental results that the devices have noticeable earthquake isolation and mitigation effect in the vertical direction. 展开更多
关键词 EARTHQUAKE ISOLATION and MITIGATION SHAKING TABLE test finite element dynamic response
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Establishment and Analysis of the Fault Tree for the Oil Transfer Pump System in CNPC Work Zone
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作者 HUANG Hui WANG Qiusheng +2 位作者 GAO Jie YANG Jiaqi XU Xiaodong 《International Journal of Plant Engineering and Management》 2014年第3期150-172,共23页
The reliability of the equipment is very important for the large petrochemical industry, especially for oil pump as the core component of driving equipment. In order to reduce the loss of the enterprise brought by equ... The reliability of the equipment is very important for the large petrochemical industry, especially for oil pump as the core component of driving equipment. In order to reduce the loss of the enterprise brought by equipment failure, it is need to find those reasons which may lead to equipment failure and take some preventive measures as early as possible. This article analyzes the failure of the oil transfer pump system in CNPC work zone systematically, qualitatively and quantitatively, using the fault tree analysis method. Then 105 groups of minimal cut sets are found, and the probability of system failure after a certain time operation is calculated by using Weibull distribution. Combined with specific requirements of reliability, the work zone may make a scientific decision of plant maintenance cycle according to the conclusion. 展开更多
关键词 fault tree reliability Weibull distribution plant maintain and management
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