The two development ways of turbocharger technology to solve the problem of matching performance with diesel were presented. The ways of waste valve gate turbocharger and variable geometry turbocharger can solve the p...The two development ways of turbocharger technology to solve the problem of matching performance with diesel were presented. The ways of waste valve gate turbocharger and variable geometry turbocharger can solve the problem of engine’s low speed torque and achieve lower smoke level. Especially for variable geometry turbocharger, it covers all conditions of engine. It can not only improve the low engine’s speed torque and keep the power performance at high engine speed, but also cover wide engine speed performance that keeps lower fuel consumption and exhaust gas temperature in full load and part load matching. The results of theory analysis and experiment research showed that it’s the ideal solution to solve the matching problem of diesel engines.展开更多
To improve the performance of the ontology matching process, a more efficient ontology matching algorithm, which can effectively eliminate unnecessary operations of matching entities, is proposed. By the theoretical a...To improve the performance of the ontology matching process, a more efficient ontology matching algorithm, which can effectively eliminate unnecessary operations of matching entities, is proposed. By the theoretical analysis and proof, a set of matching rules are summarized for depicting inherent relations among matching results of entities. Based on these rules, the proposed algorithm can reuse the matching results of two entities to directly determine the matching results of their adjacent entities. Thereby, redundant operations of matching adjacent entities can be avoided, which can improve the performance of the whole matching process. The experimental results show that, compared with related algorithms, the proposed algorithm has high matching accuracy and can remarkably reduce the consuming time of the whole matching process. So, the proposed algorithm is more competent for the large-scale ontology matching which often occurs in the practical heterogeneous web resources integration project.展开更多
According to the good charge transporting property of perovskite, we design and simulate a p–i–n-type all-perovskite solar cell by using one-dimensional device simulator. The perovskite charge transporting layers an...According to the good charge transporting property of perovskite, we design and simulate a p–i–n-type all-perovskite solar cell by using one-dimensional device simulator. The perovskite charge transporting layers and the perovskite absorber constitute the all-perovskite cell. By modulating the cell parameters, such as layer thickness values, doping concentrations and energy bands of n-, i-, and p-type perovskite layers, the all-perovskite solar cell obtains a high power conversion efficiency of 25.84%. The band matched cell shows appreciably improved performance with widen absorption spectrum and lowered recombination rate, so weobtain a high J_(sc) of 32.47 m A/cm^2. The small series resistance of the all-perovskite solar cell also benefits the high J_(sc). The simulation provides a novel thought of designing perovskite solar cells with simple producing process, low production cost and high efficient structure to solve the energy problem.展开更多
Recent advances on wheel-rail dynamic performance of curve negotiation are reviewed in this paper. There are four issues, the mechanism and calculation method of curve negotiation, the analysis and assessment of dynam...Recent advances on wheel-rail dynamic performance of curve negotiation are reviewed in this paper. There are four issues, the mechanism and calculation method of curve negotiation, the analysis and assessment of dynamic performance of vehicle, the effect of vehicle parameters on dynamic performance, and the influence of railway parameters on dynamic performance. The promising future development of wheel-rail coupled dynamics theory is analyzed in the research of curve negotiation. The framework and technique matching performance of wheel-rail dynamic interaction on the curved track are put forward for modem railways. In addition, the application of performance matching technique is introduced to the dynamic engineering, in which the wheel load is reduced obviously when the speed of train is raised to 200-250 km/h.展开更多
文摘The two development ways of turbocharger technology to solve the problem of matching performance with diesel were presented. The ways of waste valve gate turbocharger and variable geometry turbocharger can solve the problem of engine’s low speed torque and achieve lower smoke level. Especially for variable geometry turbocharger, it covers all conditions of engine. It can not only improve the low engine’s speed torque and keep the power performance at high engine speed, but also cover wide engine speed performance that keeps lower fuel consumption and exhaust gas temperature in full load and part load matching. The results of theory analysis and experiment research showed that it’s the ideal solution to solve the matching problem of diesel engines.
基金R & D Infrastructure and Facility Development(No2005DKA64201)the National High Technology Research and De-velopment Program of China (863Program) (No2006AA12Z202)
文摘To improve the performance of the ontology matching process, a more efficient ontology matching algorithm, which can effectively eliminate unnecessary operations of matching entities, is proposed. By the theoretical analysis and proof, a set of matching rules are summarized for depicting inherent relations among matching results of entities. Based on these rules, the proposed algorithm can reuse the matching results of two entities to directly determine the matching results of their adjacent entities. Thereby, redundant operations of matching adjacent entities can be avoided, which can improve the performance of the whole matching process. The experimental results show that, compared with related algorithms, the proposed algorithm has high matching accuracy and can remarkably reduce the consuming time of the whole matching process. So, the proposed algorithm is more competent for the large-scale ontology matching which often occurs in the practical heterogeneous web resources integration project.
基金Project supported by the Graduate Student Education Teaching Reform Project,China(Grant No.JG201512)the Young Teachers Research Project of Yanshan University,China(Grant No.13LGB028)
文摘According to the good charge transporting property of perovskite, we design and simulate a p–i–n-type all-perovskite solar cell by using one-dimensional device simulator. The perovskite charge transporting layers and the perovskite absorber constitute the all-perovskite cell. By modulating the cell parameters, such as layer thickness values, doping concentrations and energy bands of n-, i-, and p-type perovskite layers, the all-perovskite solar cell obtains a high power conversion efficiency of 25.84%. The band matched cell shows appreciably improved performance with widen absorption spectrum and lowered recombination rate, so weobtain a high J_(sc) of 32.47 m A/cm^2. The small series resistance of the all-perovskite solar cell also benefits the high J_(sc). The simulation provides a novel thought of designing perovskite solar cells with simple producing process, low production cost and high efficient structure to solve the energy problem.
基金support and motivation provided by National Basic Research Programof China(973 Program No.2013CB036206)National Natural Science Foundation of China(No.61134002)
文摘Recent advances on wheel-rail dynamic performance of curve negotiation are reviewed in this paper. There are four issues, the mechanism and calculation method of curve negotiation, the analysis and assessment of dynamic performance of vehicle, the effect of vehicle parameters on dynamic performance, and the influence of railway parameters on dynamic performance. The promising future development of wheel-rail coupled dynamics theory is analyzed in the research of curve negotiation. The framework and technique matching performance of wheel-rail dynamic interaction on the curved track are put forward for modem railways. In addition, the application of performance matching technique is introduced to the dynamic engineering, in which the wheel load is reduced obviously when the speed of train is raised to 200-250 km/h.