In recent decades, the world economy has been stron gl y driven by worldwide foreign direct investment (FDI) of transnational corporati ons (TNCs). And business globalisation is leading to widespread re-structuring of...In recent decades, the world economy has been stron gl y driven by worldwide foreign direct investment (FDI) of transnational corporati ons (TNCs). And business globalisation is leading to widespread re-structuring of international manufacturing systems in TNCs. However, still very little sys tematic research in manufacturing engineering or production/operations managemen t (P/O M) has focused on these new types of globalised manufacturing systems, an d little communication is organised between different academic disciplines such as manufacturing, management/ business studies, economics, geography, internatio nal development studies and so on. Many critical issues are still poorly unders tood and are not covered by current research agendas, for example: · properties of international manufacturing network systems in terms of structu ral architecture, dynamic mechanisms, strategic capabilities, strategy processes , new technology, and alliance relationships · knowledge management and organisational learning mechanisms in international manufacturing context, especially in globally coordinated networks at both intra - and inter- organisational levels · global economic trends, regional collaboration, national culture/identity, an d their impacts on industrial sector development, and company’s manufacturin g system design/re-structuring In industry, lack of global vision and appropriate strategies during internation alisation have become major barrier to the effective management of international operations. In academia, limited multi-discipline exchanges have inhibited de velopments not only in each area but also knowledge contribution to industry whi ch could arise from discipline integration. This paper, based on recent years case observations and action research work on manufacturing internationalisation, especially globalisation, introduces an evol utionary process of manufacturing systems. It seeks to explore the external and internal driving forces of the transformation and the responses of manufacturin g systems in terms of static architectures, dynamic mechanisms, and strategic ca pabilities in the evolutionary process. The paper Reviews recent researches on manufacturing internationalisation in dif ferent disciplines to gain a comprehensive picture about international manufactu ring system from different perspectives. Based on the empirical observations of industrial issues and difficulties, a further research framework is proposed to tackle wider issues in international manufacturing covering manufacturing value creation process, internationalisation process, and strategic alliance formatio n process. The paper argues that, besides deep research on three dimensions of international manufacturing system, development of strategy process to synthesis e these three processes is more important in the future research work. It sugge sts that it is necessary to enhance the collaboration between countries and disc iplines, and stimulate explorations of new frameworks that can provide more insi ghts about new manufacturing systems and foresights their development.展开更多
A new sparse channel estimation method of orthogonal frequency division multiplexing(OFDM) system based on intercarrier interference(ICI) self-cancellation is investigated. Firstly,based on the characteristic that...A new sparse channel estimation method of orthogonal frequency division multiplexing(OFDM) system based on intercarrier interference(ICI) self-cancellation is investigated. Firstly,based on the characteristic that the ICI generated by a subcarrier to the two adjacent subcarriers is approximately equal, a data pair with opposite sign and equal magnitude is modulated onto two adjacent subcarriers as pilot pair to eliminate the effect of ICI on pilots. Secondly, a new OFDM channel estimation model based on linear time-varying(LTV) model and compressed sensing(CS) is constructed, which obtains the mean of the gains of the multipath.Finally, a pilot pair optimization algorithm based on two layers loop is used to realize the minimization of the mutual coherence of the measurement matrix. For time-varying channel scenes with different numbers or delay of multipath and maximum Doppler frequency shift, the performances of several channel estimation methods are verified by simulation. The result shows that the new method has obvious advantage in both the performance of the channel estimation and the spectral efficiency.展开更多
The normalized weighted capacity reliability index of a sub-domain interconnection large scale communication network is defined and a new algorithm to calculate the reliability index is proposed, The proposed algorith...The normalized weighted capacity reliability index of a sub-domain interconnection large scale communication network is defined and a new algorithm to calculate the reliability index is proposed, The proposed algorithm can be performed using logical or algebraic operation by means of computer-aided programming and the correctness of each key step is validated in detail. This paper takes the sub-domain interconnection symmetrical topologi- cal network for a typical example to calculate the network reliability index and verifies the correctness of the proposed algorithm us- ing the real measured statistical data. The real measured results are well in accordance with the results obtained by the proposed algorithm. The result shows that the proposed algorithm is a valid means to estimate the reliability index of a sub-domain intercon- nection large-scale communication network.展开更多
To establish an efficient inter-satellite link (ISL) in an LEO network, the effect of geometric characteristics of ISL on the ISLs and the devices on the LEO satellite should be examined. Because of the continuous mov...To establish an efficient inter-satellite link (ISL) in an LEO network, the effect of geometric characteristics of ISL on the ISLs and the devices on the LEO satellite should be examined. Because of the continuous movement of the LEO satellite, the time-varying behaviours of the ISL's geometric charactersistics continuously change with the changes of the satellite's position on the orbit. These dynamic geometric characteristics of the ISLs are important for ISL's performance analyzing and the design of the devices on the LEO satellite. This paper describes dynamic geometric characteristics of ISL, analyzes the impact of these regulations on the tracking system of the satellite's antenna and the power adjusting system of the satellite's transmitter, with the Iridium system as an example.展开更多
At first, the paper reviews, analyses and discusses uplifting mechanism and history, current situation of Tibet plateau. Coal\|bearing strata and coal seam were discovered by surveying and many rocks samples and struc...At first, the paper reviews, analyses and discusses uplifting mechanism and history, current situation of Tibet plateau. Coal\|bearing strata and coal seam were discovered by surveying and many rocks samples and structural samples were collected, which established the foundation for further studying. From all above, the paper has studied strata system, time\|spatial evolution, magma activity and its regularity of continental collision of Tibet plateau and rock’s mechanical features under high temperature and pressure. The paper has also summerized tectonic features, studied geological process by time coordinate and proposed multidisciplinary geological model. The paper has proposed evolutinal model of modern structural stress field in early quaternary, modern structural stress field and crustal deformation and explored geophysical field features and deep structures from man\|mad earthquake, regional gravity field and electrical structures, thus established geophysical field model. In addition, the paper proposed overall dynamic model according to stress field, displacement orientation and velocity restriction condition, indoplate collision to Eurasia.Thoroughly, the paper has studied and stated mechanical system, non\|stability, multibody collision mechanics and mantle plume mechanical model and established mechanical model. Finally, the paper has studied numeral simulation about spheric inter\|acting during continental collision of Tibet plateau, from this, analysed and inferred its evolution history.展开更多
文摘In recent decades, the world economy has been stron gl y driven by worldwide foreign direct investment (FDI) of transnational corporati ons (TNCs). And business globalisation is leading to widespread re-structuring of international manufacturing systems in TNCs. However, still very little sys tematic research in manufacturing engineering or production/operations managemen t (P/O M) has focused on these new types of globalised manufacturing systems, an d little communication is organised between different academic disciplines such as manufacturing, management/ business studies, economics, geography, internatio nal development studies and so on. Many critical issues are still poorly unders tood and are not covered by current research agendas, for example: · properties of international manufacturing network systems in terms of structu ral architecture, dynamic mechanisms, strategic capabilities, strategy processes , new technology, and alliance relationships · knowledge management and organisational learning mechanisms in international manufacturing context, especially in globally coordinated networks at both intra - and inter- organisational levels · global economic trends, regional collaboration, national culture/identity, an d their impacts on industrial sector development, and company’s manufacturin g system design/re-structuring In industry, lack of global vision and appropriate strategies during internation alisation have become major barrier to the effective management of international operations. In academia, limited multi-discipline exchanges have inhibited de velopments not only in each area but also knowledge contribution to industry whi ch could arise from discipline integration. This paper, based on recent years case observations and action research work on manufacturing internationalisation, especially globalisation, introduces an evol utionary process of manufacturing systems. It seeks to explore the external and internal driving forces of the transformation and the responses of manufacturin g systems in terms of static architectures, dynamic mechanisms, and strategic ca pabilities in the evolutionary process. The paper Reviews recent researches on manufacturing internationalisation in dif ferent disciplines to gain a comprehensive picture about international manufactu ring system from different perspectives. Based on the empirical observations of industrial issues and difficulties, a further research framework is proposed to tackle wider issues in international manufacturing covering manufacturing value creation process, internationalisation process, and strategic alliance formatio n process. The paper argues that, besides deep research on three dimensions of international manufacturing system, development of strategy process to synthesis e these three processes is more important in the future research work. It sugge sts that it is necessary to enhance the collaboration between countries and disc iplines, and stimulate explorations of new frameworks that can provide more insi ghts about new manufacturing systems and foresights their development.
基金supported by the National Natural Science Foundation of China(61571368)
文摘A new sparse channel estimation method of orthogonal frequency division multiplexing(OFDM) system based on intercarrier interference(ICI) self-cancellation is investigated. Firstly,based on the characteristic that the ICI generated by a subcarrier to the two adjacent subcarriers is approximately equal, a data pair with opposite sign and equal magnitude is modulated onto two adjacent subcarriers as pilot pair to eliminate the effect of ICI on pilots. Secondly, a new OFDM channel estimation model based on linear time-varying(LTV) model and compressed sensing(CS) is constructed, which obtains the mean of the gains of the multipath.Finally, a pilot pair optimization algorithm based on two layers loop is used to realize the minimization of the mutual coherence of the measurement matrix. For time-varying channel scenes with different numbers or delay of multipath and maximum Doppler frequency shift, the performances of several channel estimation methods are verified by simulation. The result shows that the new method has obvious advantage in both the performance of the channel estimation and the spectral efficiency.
文摘The normalized weighted capacity reliability index of a sub-domain interconnection large scale communication network is defined and a new algorithm to calculate the reliability index is proposed, The proposed algorithm can be performed using logical or algebraic operation by means of computer-aided programming and the correctness of each key step is validated in detail. This paper takes the sub-domain interconnection symmetrical topologi- cal network for a typical example to calculate the network reliability index and verifies the correctness of the proposed algorithm us- ing the real measured statistical data. The real measured results are well in accordance with the results obtained by the proposed algorithm. The result shows that the proposed algorithm is a valid means to estimate the reliability index of a sub-domain intercon- nection large-scale communication network.
文摘To establish an efficient inter-satellite link (ISL) in an LEO network, the effect of geometric characteristics of ISL on the ISLs and the devices on the LEO satellite should be examined. Because of the continuous movement of the LEO satellite, the time-varying behaviours of the ISL's geometric charactersistics continuously change with the changes of the satellite's position on the orbit. These dynamic geometric characteristics of the ISLs are important for ISL's performance analyzing and the design of the devices on the LEO satellite. This paper describes dynamic geometric characteristics of ISL, analyzes the impact of these regulations on the tracking system of the satellite's antenna and the power adjusting system of the satellite's transmitter, with the Iridium system as an example.
文摘At first, the paper reviews, analyses and discusses uplifting mechanism and history, current situation of Tibet plateau. Coal\|bearing strata and coal seam were discovered by surveying and many rocks samples and structural samples were collected, which established the foundation for further studying. From all above, the paper has studied strata system, time\|spatial evolution, magma activity and its regularity of continental collision of Tibet plateau and rock’s mechanical features under high temperature and pressure. The paper has also summerized tectonic features, studied geological process by time coordinate and proposed multidisciplinary geological model. The paper has proposed evolutinal model of modern structural stress field in early quaternary, modern structural stress field and crustal deformation and explored geophysical field features and deep structures from man\|mad earthquake, regional gravity field and electrical structures, thus established geophysical field model. In addition, the paper proposed overall dynamic model according to stress field, displacement orientation and velocity restriction condition, indoplate collision to Eurasia.Thoroughly, the paper has studied and stated mechanical system, non\|stability, multibody collision mechanics and mantle plume mechanical model and established mechanical model. Finally, the paper has studied numeral simulation about spheric inter\|acting during continental collision of Tibet plateau, from this, analysed and inferred its evolution history.