Cloud computing technology is changing the development and usage patterns of IT infrastructure and applications. Virtualized and distributed systems as well as unified management and scheduling has greatly im proved c...Cloud computing technology is changing the development and usage patterns of IT infrastructure and applications. Virtualized and distributed systems as well as unified management and scheduling has greatly im proved computing and storage. Management has become easier, andOAM costs have been significantly reduced. Cloud desktop technology is develop ing rapidly. With this technology, users can flexibly and dynamically use virtual ma chine resources, companies＇ efficiency of using and allocating resources is greatly improved, and information security is ensured. In most existing virtual cloud desk top solutions, computing and storage are bound together, and data is stored as im age files. This limits the flexibility and expandability of systems and is insufficient for meetinz customers＇ requirements in different scenarios.展开更多
Electrodynamic tethered deorbit technology is a novel way to remove abandoned spacecrafts like upper stages or unusable satellites. This paper investigates and analyses the deorbit performance and mission applicabilit...Electrodynamic tethered deorbit technology is a novel way to remove abandoned spacecrafts like upper stages or unusable satellites. This paper investigates and analyses the deorbit performance and mission applicability of the electrodynamic tethered system. To do so, the electrodynamic tethered deorbit dynamics with multi-perturbation is firstly formulated, where the Earth magnetic field, the atmospheric drag, and the Earth oblateness effect are considered. Then, the key system parameters, including payload mass, tether length and tether type, are analyzed by numerical simulations to investigate their influences on the deorbit performance and to give the setting principles for choosing system parameters. Based on this and given an appropriate group of system parameters, numerical simulations are undertaken to study the impact of the mission parameters, including orbit height and orbit inclination, and thus to investigate the mission applicability of the electrodynamic tethered deorbit technology.展开更多
As emerging technologies have advanced,some countries have issued reports on human performance enhancement efforts in recent years.Human performance enhancement is a prominent theme in the military field.As a type of ...As emerging technologies have advanced,some countries have issued reports on human performance enhancement efforts in recent years.Human performance enhancement is a prominent theme in the military field.As a type of potentially disruptive technology,human performance enhancement technology(HPET)is of vital importance in promoting military combat effectiveness,developing national defense science and technology,and transforming military medicine.This paper analyzes the current development status of critical HPETs,examines challenges facing such development,and points out existing problems in the field.Finally,future development directions of HPET are suggested.We hope this review will be of interest to scientists and engineers,who should carefully develop this technology to maximize human potential and focus on our social security.展开更多
Based on the global patents of 109 mobile phone vendors filed from 1992 to 2016 and sales data from 2002to 2016, this study formulates technological and market competition networks. We find that an increasingly large ...Based on the global patents of 109 mobile phone vendors filed from 1992 to 2016 and sales data from 2002to 2016, this study formulates technological and market competition networks. We find that an increasingly large number of firms joined the market, leading to a competition network of increasingly larger scale and greater density. We also propose indicators to measure competitive intensity, which reflects the extent to which the firms are competing against each other. We examine the role of competitive intensity in mediating firms’ performance. We employ a weighted least squares regression model for the empirical analysis. The empirical results confirm the significant role of competitive intensity in determining firm performance. However, in technological and market competition networks, competitive intensity generates essentially different mediating impacts. For technological competition, competitive intensity positively mediates the impact between the leaders’ and followers’ technological performances. There is an asymmetric mediating effect that enlarges the gap between the technological performances of leading vendors and their followers. Accordingly, competitive intensity may generate different impacts on the technological performance of leaders and followers. In comparison, the competitive intensity embedded in the market competition network has a symmetrical role in mediating the mutual impact between the leaders’ and followers’ market performances, that is, it neither enlarges nor narrows the market performance gap between leaders and followers. Therefore, when creating a development strategy, firm managers need to account for their competitors’ behaviors, carefully analyze the significance of these behaviors, and adjust their strategic arrangements in a timely manner.展开更多
China has been developed into one of the most active regions in terms of both fundamental and applied research on magnesium （Mg） and its alloys in the world from a solid base laid by its prominent metallurgist and m...China has been developed into one of the most active regions in terms of both fundamental and applied research on magnesium （Mg） and its alloys in the world from a solid base laid by its prominent metallurgist and materials scientists over the past decades. Nowadays, a large number of young-generation researchers have been inspired by their predecessors and become the key participants in the fields of Mg alloys, which consequently led to the establishment of China Youth Scholar Society for Magnesium Alloys Research in 2015. Since then, the first two China Youth Scholars Symposiums on Mg Alloys Research had been held at Harbin （2015） and Chongqing （2016） China, respectively. A number of crucial research inter- ests related to fundamental and applied Mg research were discussed at the conferences and summarized in this short perspective, aiming to boost far-reaching initiatives for development of new Mg-based materials to satisfy the requirements for a broad range of industrial employments. Herein, four main aspects are included as follows： i） Plastic deformation mechanism and strengthening strategy, ii） Design and development of new Mg-based materials, iii） Key service properties, and iv） New processing technologies.展开更多
The equilibrium and kinetic characteristics of the adsorption of erythromycin to Sepabeads SP825 were determined.The equilibrium data in a batch system was well described by a Langmuir isotherm.The separation performa...The equilibrium and kinetic characteristics of the adsorption of erythromycin to Sepabeads SP825 were determined.The equilibrium data in a batch system was well described by a Langmuir isotherm.The separation performance was investigated in a fixed-bed system with respect to the adsorption superficial velocity,ionic strength and pH.A mathematical model was used to simulate the mass transfer mechanism,taking film mass transfer,pore diffusion and axial dispersion into account.The model predictions were consistent with the experi-mental data and were consequently used to determine the mass transfer coefficients.展开更多
文摘Cloud computing technology is changing the development and usage patterns of IT infrastructure and applications. Virtualized and distributed systems as well as unified management and scheduling has greatly im proved computing and storage. Management has become easier, andOAM costs have been significantly reduced. Cloud desktop technology is develop ing rapidly. With this technology, users can flexibly and dynamically use virtual ma chine resources, companies＇ efficiency of using and allocating resources is greatly improved, and information security is ensured. In most existing virtual cloud desk top solutions, computing and storage are bound together, and data is stored as im age files. This limits the flexibility and expandability of systems and is insufficient for meetinz customers＇ requirements in different scenarios.
文摘Electrodynamic tethered deorbit technology is a novel way to remove abandoned spacecrafts like upper stages or unusable satellites. This paper investigates and analyses the deorbit performance and mission applicability of the electrodynamic tethered system. To do so, the electrodynamic tethered deorbit dynamics with multi-perturbation is firstly formulated, where the Earth magnetic field, the atmospheric drag, and the Earth oblateness effect are considered. Then, the key system parameters, including payload mass, tether length and tether type, are analyzed by numerical simulations to investigate their influences on the deorbit performance and to give the setting principles for choosing system parameters. Based on this and given an appropriate group of system parameters, numerical simulations are undertaken to study the impact of the mission parameters, including orbit height and orbit inclination, and thus to investigate the mission applicability of the electrodynamic tethered deorbit technology.
基金This work was supported by the Independent Project of the Key Laboratory of Human Factors Engineering(SYFD160051806)the Foundation of the Key Laboratory for Equipment Advanced Research(6142222180204)+1 种基金the Foundation Project in the field of Equipment Advanced Research(61400020402)the Military Science and Technology Commission National Defense Science and Technology Innovation Zone Project(1716312ZT00212101).
文摘As emerging technologies have advanced,some countries have issued reports on human performance enhancement efforts in recent years.Human performance enhancement is a prominent theme in the military field.As a type of potentially disruptive technology,human performance enhancement technology(HPET)is of vital importance in promoting military combat effectiveness,developing national defense science and technology,and transforming military medicine.This paper analyzes the current development status of critical HPETs,examines challenges facing such development,and points out existing problems in the field.Finally,future development directions of HPET are suggested.We hope this review will be of interest to scientists and engineers,who should carefully develop this technology to maximize human potential and focus on our social security.
基金funded by the National Natural Science Foundation of China(71872169,71874175)Fundamental Research Funds for the Central UniversitiesUniversity of Chinese Academy of Sciences(E1E42107)
文摘Based on the global patents of 109 mobile phone vendors filed from 1992 to 2016 and sales data from 2002to 2016, this study formulates technological and market competition networks. We find that an increasingly large number of firms joined the market, leading to a competition network of increasingly larger scale and greater density. We also propose indicators to measure competitive intensity, which reflects the extent to which the firms are competing against each other. We examine the role of competitive intensity in mediating firms’ performance. We employ a weighted least squares regression model for the empirical analysis. The empirical results confirm the significant role of competitive intensity in determining firm performance. However, in technological and market competition networks, competitive intensity generates essentially different mediating impacts. For technological competition, competitive intensity positively mediates the impact between the leaders’ and followers’ technological performances. There is an asymmetric mediating effect that enlarges the gap between the technological performances of leading vendors and their followers. Accordingly, competitive intensity may generate different impacts on the technological performance of leaders and followers. In comparison, the competitive intensity embedded in the market competition network has a symmetrical role in mediating the mutual impact between the leaders’ and followers’ market performances, that is, it neither enlarges nor narrows the market performance gap between leaders and followers. Therefore, when creating a development strategy, firm managers need to account for their competitors’ behaviors, carefully analyze the significance of these behaviors, and adjust their strategic arrangements in a timely manner.
基金support from Chinese Committee for Magnesium and its Application
文摘China has been developed into one of the most active regions in terms of both fundamental and applied research on magnesium （Mg） and its alloys in the world from a solid base laid by its prominent metallurgist and materials scientists over the past decades. Nowadays, a large number of young-generation researchers have been inspired by their predecessors and become the key participants in the fields of Mg alloys, which consequently led to the establishment of China Youth Scholar Society for Magnesium Alloys Research in 2015. Since then, the first two China Youth Scholars Symposiums on Mg Alloys Research had been held at Harbin （2015） and Chongqing （2016） China, respectively. A number of crucial research inter- ests related to fundamental and applied Mg research were discussed at the conferences and summarized in this short perspective, aiming to boost far-reaching initiatives for development of new Mg-based materials to satisfy the requirements for a broad range of industrial employments. Herein, four main aspects are included as follows： i） Plastic deformation mechanism and strengthening strategy, ii） Design and development of new Mg-based materials, iii） Key service properties, and iv） New processing technologies.
文摘The equilibrium and kinetic characteristics of the adsorption of erythromycin to Sepabeads SP825 were determined.The equilibrium data in a batch system was well described by a Langmuir isotherm.The separation performance was investigated in a fixed-bed system with respect to the adsorption superficial velocity,ionic strength and pH.A mathematical model was used to simulate the mass transfer mechanism,taking film mass transfer,pore diffusion and axial dispersion into account.The model predictions were consistent with the experi-mental data and were consequently used to determine the mass transfer coefficients.
