From Nov. 5 to 6, 2013, the China Society for Human Rights Studies (CSHRS)held the Fifth National Meeting for the Exchange of Work Experience Among Human Rights Research Institutions at Wuhan University. More than 1...From Nov. 5 to 6, 2013, the China Society for Human Rights Studies (CSHRS)held the Fifth National Meeting for the Exchange of Work Experience Among Human Rights Research Institutions at Wuhan University. More than 100 experts and scholars, focusing on empirical human rights studies and their contribution to building a society based on the rule of law, shared their work experience and discussed effective strategies. CSHRS President Luo Haocai, who served as vice chairman of the 10th National Committee of the Chinese People's Political Consultative Conference,展开更多
Dipole Research EXperiment(DREX) is a new terrella device as part of the Space Plasma Environment Research Facility(SPERF) for laboratory studies of space physics relevant to the inner magnetospheric plasmas. Adeq...Dipole Research EXperiment(DREX) is a new terrella device as part of the Space Plasma Environment Research Facility(SPERF) for laboratory studies of space physics relevant to the inner magnetospheric plasmas. Adequate plasma sources are very important for DREX to achieve its scientific goals. According to different research requirements, there are two density regimes for DREX. The low density regime will be achieved by an electron cyclotron resonance(ECR) system for the ‘whistler/chorus' wave investigation, while the high density regime will be achieved by biased cold cathode discharge for the desired ‘Alfvén' wave study. The parameters of ‘whistler/chorus' waves and ‘Alfvén' waves are determined by the scaling law between space and laboratory plasmas in the current device. In this paper, the initial design of these two plasma sources for DREX is described. Focus is placed on the chosen frequency and operation mode of the ECR system which will produce relatively low density ‘artificial radiation belt' plasmas and the seed electrons, followed by the design of biased cold cathode discharge to generate plasma with high density.展开更多
Due to their significant roles in the radiation belts dynamics, chorus waves are widely investigaled in observations, experiments, and simulations. In this paper, numerical studies for the generation of chorus-like wa...Due to their significant roles in the radiation belts dynamics, chorus waves are widely investigaled in observations, experiments, and simulations. In this paper, numerical studies for the generation of chorus-like waves in a launching device, dipole research experiment (DREX), are carried out by a hybrid code. The DREX plasma is generated b} electron cyclotron resonance (ECR), which leads to an intrinsic temperature anisotropy of energetic electrons. Thus the whistler instability can be excited in the device. We then investigate the effects of three parameters, i.e., the cold plasma density no, the hot plasma density nh, and the parallel thermal velocity of energetic electrons, on the generation of chorus-like waves under the DREX design parameters. It is obtained that a larger temperature anisotropy is needed to excite chorus-like waves with a high nc with other parameters fixed. Then we fix the plasma density and parallel thermal velocity, while varying the hot plasma density. It is found that with the increase of nh, the spectrum of the generated waves changes from no chorus elements, to that with several chorus elements, and then further to broad-band hiss-like waves. Besides, different structures of chorus- like waves, such as rising-tone and/or falling-tone structures, can be generated at different parallel thermal velocities in the DREX parameter range.展开更多
The Ca(OH)_(2)/CaO thermochemical energy storage(TCES)system based on calcium looping has received extensive attention owing to its high energy storage density,prolonged energy storage time,and environmental friendlin...The Ca(OH)_(2)/CaO thermochemical energy storage(TCES)system based on calcium looping has received extensive attention owing to its high energy storage density,prolonged energy storage time,and environmental friendliness.The heat storage process of the Ca(OH)_(2)/CaO TCES system in a mixed heating reactor was evaluated in this study,by employing a combination of direct and indirect heating modes.The dehydration process was studied experimentally,and a numerical model was established and verified based on the experimental results.The dehydration behavior of 500 g of Ca(OH)_(2) powder was investigated in a fixed-bed reactor with mixed heating.The experimental and simulation results indicated that mixed heating causes combined centripetal and horizontal propulsion.Heat input is the main limiting factor in the heat storage process,because the radial advance of the reaction is hindered by the low thermal conductivity of the solid reactant particles.Heat transmission partitions were added to enhance the performance of the reactor.The performance of the modified reactor was compared with that of a conventional reactor.The radial heat transmission partitions in the modified reactor effectively enhance the energy storage rate and reduce the reaction time by 59.5%compared with the reactor without partitions.展开更多
Blockchain,like any other complex technology,needs a strong testing methodology to support its evolution in both research and development contexts.Setting up meaningful tests for permissionless blockchain technology i...Blockchain,like any other complex technology,needs a strong testing methodology to support its evolution in both research and development contexts.Setting up meaningful tests for permissionless blockchain technology is a notoriously complex task for several reasons:software is complex,a large number of nodes are involved,the network is non-ideal,etc.Developers usually adopt small virtual laboratories or costly real devnets based on real software.Researchers usually prefer simulations of a large number of nodes based on simplified models.In this paper,we aim to obtain the advantages of both approaches,i.e.,performing large,realistic,inexpensive,and flexible experiments,using real blockchain software within a virtual environment.To do that,we address the challenge of running large blockchain networks in a single physical machine,leveraging Linux and Docker.We analyze a number of problems that arise when large blockchain networks are emulated,and we provide technical solutions for all of them.Finally,we describe two experiences of emulating fairly large blockchain networks on a single machine:adopting both research-oriented and production-oriented software and involving more than 3000 containers.展开更多
In order to study the effects of loading condition and temperature on the dynamic properties of asphalt mixtures, the dynamic loading tests on different loading condition (various speeds and loads under a certain rou...In order to study the effects of loading condition and temperature on the dynamic properties of asphalt mixtures, the dynamic loading tests on different loading condition (various speeds and loads under a certain roughness) and temperature conditions were performed. The experimental result show that the dynamic properties of asphalt mixtures are influenced by vehicle load and speed, besides, the effects of temperature on dynamic properties of asphalt mixture are significant.展开更多
The inlet swirl distortion and non-uniform tip clearance have great effects on aero-engine performance and stall margin.In this paper,the effects of paired swirl distortion on the aerodynamic stability and stall incep...The inlet swirl distortion and non-uniform tip clearance have great effects on aero-engine performance and stall margin.In this paper,the effects of paired swirl distortion on the aerodynamic stability and stall inception of a single stage axial compressor with non-uniform tip clearance are quantitatively analyzed by using the swirl distortion descriptors.The experimental results show that the paired swirl distortion dominated by co-rotating swirl improves the stability of the axial compressor.For a single-stage axial compressor with eccentricity of 100%,the stall inception starts at the maximum tip clearance with clean inlet.The initial position of the stall inception is determined by the maximum tip clearance when the small intensity paired swirl distortion exists at the compressor inlet.As the swirl intensity increases,it shifts towards the position of the counter rotating swirl vortex core.The inlet swirl will not change the type of stall inception.展开更多
文摘From Nov. 5 to 6, 2013, the China Society for Human Rights Studies (CSHRS)held the Fifth National Meeting for the Exchange of Work Experience Among Human Rights Research Institutions at Wuhan University. More than 100 experts and scholars, focusing on empirical human rights studies and their contribution to building a society based on the rule of law, shared their work experience and discussed effective strategies. CSHRS President Luo Haocai, who served as vice chairman of the 10th National Committee of the Chinese People's Political Consultative Conference,
基金supported by National Natural Science Foundation of China(Nos.11505040,11261140326,11405038 and 51577043)China Postdoctoral Science Foundation(Nos.2016M591518,2015M570283)HIT.NSRIF under Grant No.2017008
文摘Dipole Research EXperiment(DREX) is a new terrella device as part of the Space Plasma Environment Research Facility(SPERF) for laboratory studies of space physics relevant to the inner magnetospheric plasmas. Adequate plasma sources are very important for DREX to achieve its scientific goals. According to different research requirements, there are two density regimes for DREX. The low density regime will be achieved by an electron cyclotron resonance(ECR) system for the ‘whistler/chorus' wave investigation, while the high density regime will be achieved by biased cold cathode discharge for the desired ‘Alfvén' wave study. The parameters of ‘whistler/chorus' waves and ‘Alfvén' waves are determined by the scaling law between space and laboratory plasmas in the current device. In this paper, the initial design of these two plasma sources for DREX is described. Focus is placed on the chosen frequency and operation mode of the ECR system which will produce relatively low density ‘artificial radiation belt' plasmas and the seed electrons, followed by the design of biased cold cathode discharge to generate plasma with high density.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.41674165,41631071,41474142,and 41674174)the China Postdoctoral Science Foundation(Grant No.2015M570283)
文摘Due to their significant roles in the radiation belts dynamics, chorus waves are widely investigaled in observations, experiments, and simulations. In this paper, numerical studies for the generation of chorus-like waves in a launching device, dipole research experiment (DREX), are carried out by a hybrid code. The DREX plasma is generated b} electron cyclotron resonance (ECR), which leads to an intrinsic temperature anisotropy of energetic electrons. Thus the whistler instability can be excited in the device. We then investigate the effects of three parameters, i.e., the cold plasma density no, the hot plasma density nh, and the parallel thermal velocity of energetic electrons, on the generation of chorus-like waves under the DREX design parameters. It is obtained that a larger temperature anisotropy is needed to excite chorus-like waves with a high nc with other parameters fixed. Then we fix the plasma density and parallel thermal velocity, while varying the hot plasma density. It is found that with the increase of nh, the spectrum of the generated waves changes from no chorus elements, to that with several chorus elements, and then further to broad-band hiss-like waves. Besides, different structures of chorus- like waves, such as rising-tone and/or falling-tone structures, can be generated at different parallel thermal velocities in the DREX parameter range.
文摘The Ca(OH)_(2)/CaO thermochemical energy storage(TCES)system based on calcium looping has received extensive attention owing to its high energy storage density,prolonged energy storage time,and environmental friendliness.The heat storage process of the Ca(OH)_(2)/CaO TCES system in a mixed heating reactor was evaluated in this study,by employing a combination of direct and indirect heating modes.The dehydration process was studied experimentally,and a numerical model was established and verified based on the experimental results.The dehydration behavior of 500 g of Ca(OH)_(2) powder was investigated in a fixed-bed reactor with mixed heating.The experimental and simulation results indicated that mixed heating causes combined centripetal and horizontal propulsion.Heat input is the main limiting factor in the heat storage process,because the radial advance of the reaction is hindered by the low thermal conductivity of the solid reactant particles.Heat transmission partitions were added to enhance the performance of the reactor.The performance of the modified reactor was compared with that of a conventional reactor.The radial heat transmission partitions in the modified reactor effectively enhance the energy storage rate and reduce the reaction time by 59.5%compared with the reactor without partitions.
基金supported by project SERICS(PE00000014)under the MUR National Recovery and Resilience Plan funded by the European Union-NextGenerationEU.
文摘Blockchain,like any other complex technology,needs a strong testing methodology to support its evolution in both research and development contexts.Setting up meaningful tests for permissionless blockchain technology is a notoriously complex task for several reasons:software is complex,a large number of nodes are involved,the network is non-ideal,etc.Developers usually adopt small virtual laboratories or costly real devnets based on real software.Researchers usually prefer simulations of a large number of nodes based on simplified models.In this paper,we aim to obtain the advantages of both approaches,i.e.,performing large,realistic,inexpensive,and flexible experiments,using real blockchain software within a virtual environment.To do that,we address the challenge of running large blockchain networks in a single physical machine,leveraging Linux and Docker.We analyze a number of problems that arise when large blockchain networks are emulated,and we provide technical solutions for all of them.Finally,we describe two experiences of emulating fairly large blockchain networks on a single machine:adopting both research-oriented and production-oriented software and involving more than 3000 containers.
基金Funded by the Science and Technology Program of Communications Depart-ment of Henan Province(No.2006P335)
文摘In order to study the effects of loading condition and temperature on the dynamic properties of asphalt mixtures, the dynamic loading tests on different loading condition (various speeds and loads under a certain roughness) and temperature conditions were performed. The experimental result show that the dynamic properties of asphalt mixtures are influenced by vehicle load and speed, besides, the effects of temperature on dynamic properties of asphalt mixture are significant.
基金supported by National Science and Technology Major Project(Grant No.2017-II-0004-0017)。
文摘The inlet swirl distortion and non-uniform tip clearance have great effects on aero-engine performance and stall margin.In this paper,the effects of paired swirl distortion on the aerodynamic stability and stall inception of a single stage axial compressor with non-uniform tip clearance are quantitatively analyzed by using the swirl distortion descriptors.The experimental results show that the paired swirl distortion dominated by co-rotating swirl improves the stability of the axial compressor.For a single-stage axial compressor with eccentricity of 100%,the stall inception starts at the maximum tip clearance with clean inlet.The initial position of the stall inception is determined by the maximum tip clearance when the small intensity paired swirl distortion exists at the compressor inlet.As the swirl intensity increases,it shifts towards the position of the counter rotating swirl vortex core.The inlet swirl will not change the type of stall inception.