Main design parameters of MCC （metallic card clothing） which include front angle, base width, tooth pitch, and tooth point dimensions are discussed to investigate the carding effect of MCC. Experimental results show...Main design parameters of MCC （metallic card clothing） which include front angle, base width, tooth pitch, and tooth point dimensions are discussed to investigate the carding effect of MCC. Experimental results show that type C machine has the best carding effect, which is not ascribed to single factor control but the integrated design optimization and good performance of wire teeth. In comparison with the teeth design, the wire performance is another important factor that influences the perfommnce of modem high efficient production carding machine.展开更多
In this paper they deal with the issue of specification and design of parallel communicatingprocesses. A trace-state based model is introduced to describe the behaviour of concurrent programs. They presenta formal sys...In this paper they deal with the issue of specification and design of parallel communicatingprocesses. A trace-state based model is introduced to describe the behaviour of concurrent programs. They presenta formal system based on that model to achieve hierarchical and modular development and verification methods. Anumber of refinement rules are used to decompose the specification into smaller ones and calculate program fromthe展开更多
The application of a closed-loop specification oriented feedback control design method, which addresses the design of controllers to satisfy multiple simultaneous conflicting closed-loop performance specifications is ...The application of a closed-loop specification oriented feedback control design method, which addresses the design of controllers to satisfy multiple simultaneous conflicting closed-loop performance specifications is presented. The proposed approach is well suited to the design of controllers which must meet a set of conflicting performance specifications. Gain tuning is central to the design process, however, the tuning process is greatly simplified over that presented by the problem of tuning a PID controller for example. The proposed control method is applied to an AC induction motor, with an inner-loop flux vector controller applied to design a position control system. Experimental results verify the effectiveness of this method.展开更多
The Federal Highway Administration (FHWA) sponsored a large,multi-year project conducted by the Multidisciplinary Center for Earthquake Engineering Research (MCEER) titled'Seismic Vulnerability of New Highway Cons...The Federal Highway Administration (FHWA) sponsored a large,multi-year project conducted by the Multidisciplinary Center for Earthquake Engineering Research (MCEER) titled'Seismic Vulnerability of New Highway Construction'(MCEER Project 112),which was completed in 1998.MCEER coordinated the work of many researchers,who performed studies on the seismic design and vulnerability analysis of highway bridges,tunnels,and retaining structures. Extensive research was conducted to provide revisions and improvements to current design and detailing approaches and national design specifications for highway bridges.The program included both analytical and experimental studies,and addressed seismic hazard exposure and ground motion input for the U.S.highway system;foundation design and soil behavior: structural importance,analysis,and response:structural design issues and details;and structural design criteria.展开更多
In the U.S., the current Load and Resistance Factor Design （LRFD） Specifications for highway bridges is a reliability-based formulation that considers failure probabilities of bridge components due to the actions of...In the U.S., the current Load and Resistance Factor Design （LRFD） Specifications for highway bridges is a reliability-based formulation that considers failure probabilities of bridge components due to the actions of typical dead load and frequent vehicular loads. Various extreme load effects, such as earthquake and vessel collision, are on the same reliability-based platform. Since these extreme loads are time variables, combining them with not considered frequent. non- extreme loads is a significant challenge. The number of design limit state equations based on these failure probabilities can be unrealistically large and unnecessary from the view point of practical applications. Based on the opinion of AASHTO State Bridge Engineers, many load combinations are insignificant in their states. This paper describes the formulation of a criterion to include only the necessary load combinations to establish the design limit states. This criterion is established by examining the total failure probabilities for all possible time-invariant and time varying load combinations and breaking them down into partial terms. Then, important load combinations can be readily determined quantitatively,展开更多
To diminish the thermal load, two ways, that is, in-band direct pumping and micro-rod crystal, could be adopted at the same time. The efficiency of LD in-band direct-pumping side surface polished micro-rod Nd：YVO_4 l...To diminish the thermal load, two ways, that is, in-band direct pumping and micro-rod crystal, could be adopted at the same time. The efficiency of LD in-band direct-pumping side surface polished micro-rod Nd：YVO_4 laser is numerically analyzed. By optimizing parameters such as crystal length, laser mode radius, pump beam radius, doping concentration and crystal cross-section size, the overall efficiency can reach over 50%. It is found that with micro-rod crystal implemented in the laser oscillator, high overall efficiency LD in-band direct-pumping Nd：YVO_4 laser could be realized. High efficiency combined with low thermal load makes this laser an outstanding scheme for building high-power Nd：YVO_4 lasers.展开更多
The main technical backgrounds and requirements are introduced with regard to earthquake ground motion design parameters in several domestic and American standards,codes and guides involved in the seismic analysis and...The main technical backgrounds and requirements are introduced with regard to earthquake ground motion design parameters in several domestic and American standards,codes and guides involved in the seismic analysis and design activities of nuclear power plants in China.Based on the research results from site seismic safety evaluation of domestic nuclear power plant projects in the last years,characteristics and differences of site specific design spectra are analyzed in comparison with standard response spectra,and the suitability of standard response spectra for domestic nuclear power plant projects is discussed.展开更多
We proposed the concept of parallel injection power amplification. A tapered fiber amplifier with multi-seed sources by the way of parallel injection was studied. The lower-order modes are excited and more than 90% of...We proposed the concept of parallel injection power amplification. A tapered fiber amplifier with multi-seed sources by the way of parallel injection was studied. The lower-order modes are excited and more than 90% of the input signal power remains in the fiber core if optimal injection and taper design are set. The power in the doped-core is amplified with high optical-optical efficiency. When light is propagating along the fiber, the higher-order modes are filtered which results in the high output beam quality. Incoherent combination of multi-seed lights launched through the wide end gives rise to the output power of several kW.展开更多
文摘Main design parameters of MCC （metallic card clothing） which include front angle, base width, tooth pitch, and tooth point dimensions are discussed to investigate the carding effect of MCC. Experimental results show that type C machine has the best carding effect, which is not ascribed to single factor control but the integrated design optimization and good performance of wire teeth. In comparison with the teeth design, the wire performance is another important factor that influences the perfommnce of modem high efficient production carding machine.
基金ESPRIT Basic Research ProCoS project 3104 and 7071
文摘In this paper they deal with the issue of specification and design of parallel communicatingprocesses. A trace-state based model is introduced to describe the behaviour of concurrent programs. They presenta formal system based on that model to achieve hierarchical and modular development and verification methods. Anumber of refinement rules are used to decompose the specification into smaller ones and calculate program fromthe
文摘The application of a closed-loop specification oriented feedback control design method, which addresses the design of controllers to satisfy multiple simultaneous conflicting closed-loop performance specifications is presented. The proposed approach is well suited to the design of controllers which must meet a set of conflicting performance specifications. Gain tuning is central to the design process, however, the tuning process is greatly simplified over that presented by the problem of tuning a PID controller for example. The proposed control method is applied to an AC induction motor, with an inner-loop flux vector controller applied to design a position control system. Experimental results verify the effectiveness of this method.
基金the Federal Highway Administration under contract number DTFH61-92-C-00112.
文摘The Federal Highway Administration (FHWA) sponsored a large,multi-year project conducted by the Multidisciplinary Center for Earthquake Engineering Research (MCEER) titled'Seismic Vulnerability of New Highway Construction'(MCEER Project 112),which was completed in 1998.MCEER coordinated the work of many researchers,who performed studies on the seismic design and vulnerability analysis of highway bridges,tunnels,and retaining structures. Extensive research was conducted to provide revisions and improvements to current design and detailing approaches and national design specifications for highway bridges.The program included both analytical and experimental studies,and addressed seismic hazard exposure and ground motion input for the U.S.highway system;foundation design and soil behavior: structural importance,analysis,and response:structural design issues and details;and structural design criteria.
基金Federal Highway Administration at the University at Buffalo under Contract No.DTFH61-08-C-00012
文摘In the U.S., the current Load and Resistance Factor Design （LRFD） Specifications for highway bridges is a reliability-based formulation that considers failure probabilities of bridge components due to the actions of typical dead load and frequent vehicular loads. Various extreme load effects, such as earthquake and vessel collision, are on the same reliability-based platform. Since these extreme loads are time variables, combining them with not considered frequent. non- extreme loads is a significant challenge. The number of design limit state equations based on these failure probabilities can be unrealistically large and unnecessary from the view point of practical applications. Based on the opinion of AASHTO State Bridge Engineers, many load combinations are insignificant in their states. This paper describes the formulation of a criterion to include only the necessary load combinations to establish the design limit states. This criterion is established by examining the total failure probabilities for all possible time-invariant and time varying load combinations and breaking them down into partial terms. Then, important load combinations can be readily determined quantitatively,
文摘To diminish the thermal load, two ways, that is, in-band direct pumping and micro-rod crystal, could be adopted at the same time. The efficiency of LD in-band direct-pumping side surface polished micro-rod Nd：YVO_4 laser is numerically analyzed. By optimizing parameters such as crystal length, laser mode radius, pump beam radius, doping concentration and crystal cross-section size, the overall efficiency can reach over 50%. It is found that with micro-rod crystal implemented in the laser oscillator, high overall efficiency LD in-band direct-pumping Nd：YVO_4 laser could be realized. High efficiency combined with low thermal load makes this laser an outstanding scheme for building high-power Nd：YVO_4 lasers.
基金funded by the Basic Science Research Foundation of IEM(Grant No.2006A02)the National Natural Sciences Foundation of China (90715038)
文摘The main technical backgrounds and requirements are introduced with regard to earthquake ground motion design parameters in several domestic and American standards,codes and guides involved in the seismic analysis and design activities of nuclear power plants in China.Based on the research results from site seismic safety evaluation of domestic nuclear power plant projects in the last years,characteristics and differences of site specific design spectra are analyzed in comparison with standard response spectra,and the suitability of standard response spectra for domestic nuclear power plant projects is discussed.
文摘We proposed the concept of parallel injection power amplification. A tapered fiber amplifier with multi-seed sources by the way of parallel injection was studied. The lower-order modes are excited and more than 90% of the input signal power remains in the fiber core if optimal injection and taper design are set. The power in the doped-core is amplified with high optical-optical efficiency. When light is propagating along the fiber, the higher-order modes are filtered which results in the high output beam quality. Incoherent combination of multi-seed lights launched through the wide end gives rise to the output power of several kW.
