Power electronics is an enabling technology for the development of environmental friendly fuel cell vehicles, and to implement the various vehicle electrical architectures to obtain the best performance. In this paper...Power electronics is an enabling technology for the development of environmental friendly fuel cell vehicles, and to implement the various vehicle electrical architectures to obtain the best performance. In this paper, power conversion strategies for propulsion and auxiliary power unit applications are described. The power electronics strategies for the successful development of the fuel cell vehicles are presented. The fuel cell systems for propulsion and for auxiliary power unit applications are also discussed.展开更多
One-way traffic organization is a direct, efficient and economic method to solve traffic congestion and expand traffic capacity. With its evolution, advantages and disadvantages introduced its setting conditions demon...One-way traffic organization is a direct, efficient and economic method to solve traffic congestion and expand traffic capacity. With its evolution, advantages and disadvantages introduced its setting conditions demon strated. The general method and processes are summarized in planning for urban one-way streets project, viz. in vestigation, drawing out and evaluation of project, selecting of project and beneficial analysis. Fuzzy synthetical evaluation other fields is employed to evaluate the project. Its evaluation system and method is introduced and Delphi method is adopted to obtain evaluation index. Finally, taking Harbin city as an example, the application process of above-mentioned method is illuminated. Accordingly, it is proved that the method is exercisable.展开更多
Previously,we had identified the various dynamic mechanisms of a wide range air to fuel ratio sensor operated in the engine exhaust by using the transfer function approach.In this study,we utilized these results to mo...Previously,we had identified the various dynamic mechanisms of a wide range air to fuel ratio sensor operated in the engine exhaust by using the transfer function approach.In this study,we utilized these results to model the real time sensor response to an engine exhaust excursion.In the fitting,we identified a new dynamic mechanism,which was not detected in the previous transfer function study.This new dynamic occurred at the stoichiometric point when the engine changed from rich to lean.This new mechanism involved the depletion of the adsorbed fuel species on the electrode surface by an oxidation process. The dynamics of this effect depends on the ratio of the diffusion flux of the sensor-coating layer to the total adsorbed gas species on the electrode surface.The smaller the ratio is,the slower the dynamic mechanism will be.展开更多
The conceptual design of mechatronic systems is addressed under the thrust of concurrent engineering and an enhanced conceptual design methodology describing the early design stage of mechatronic systems is presented ...The conceptual design of mechatronic systems is addressed under the thrust of concurrent engineering and an enhanced conceptual design methodology describing the early design stage of mechatronic systems is presented through an example illustration of a pick and place robot.This methodology treats each feasible solution as a solution strategy.In the methodology,Quality Function Deployment(QFD)is used as a baseline for the analysis of the mapping from customers to engineering requirements,Axiomatic Design(AD)is adopted as a guideline to generate feasible,good design solution alternatives,and Theory of Inventive Problem Solving(TRIZ)is applied to deal with domain conflicts in design.展开更多
Novel plastics that are biodegradable, environmentally benign, and made from renewable natural resources are currently being researched as alternatives to traditional petroleum-based plastics. One such plastic, thermo...Novel plastics that are biodegradable, environmentally benign, and made from renewable natural resources are currently being researched as alternatives to traditional petroleum-based plastics. One such plastic, thermoplastic starch (TPS) is produced from starch processed at high temperatures in the presence of plasticizers, such as water and glycerol. However, because of its hydrophilic nature, TPS exhibits poor mechanical properties when exposed to environmental conditions, such as rain or humidity. The overall objective of this research work was to produce a thermoplastic starch based material with low water absorption that may be used to replace petroleum-based plastics. With a recent emergence of “green” polyethylene (GPE), sourced from renewable feedstock, it has become possible to develop novel biodegradable polymers for various applications. In this work, GPE was melt blended with starch in three different ways;reactive extrusion of GPE and starch facilitated by maleic anhydride (MAH) and dicumyl peroxide (DCP), melt blending of GPE and starch by extrusion, and melt blending of maleated polyethylene and starch by extrusion. Comprehensive testing and analysis has shown that all methods reduced water absorption significantly with some variations across the board.展开更多
文摘Power electronics is an enabling technology for the development of environmental friendly fuel cell vehicles, and to implement the various vehicle electrical architectures to obtain the best performance. In this paper, power conversion strategies for propulsion and auxiliary power unit applications are described. The power electronics strategies for the successful development of the fuel cell vehicles are presented. The fuel cell systems for propulsion and for auxiliary power unit applications are also discussed.
基金Sponsored by the National Natural Science of China(Grant No. 50278026)
文摘One-way traffic organization is a direct, efficient and economic method to solve traffic congestion and expand traffic capacity. With its evolution, advantages and disadvantages introduced its setting conditions demon strated. The general method and processes are summarized in planning for urban one-way streets project, viz. in vestigation, drawing out and evaluation of project, selecting of project and beneficial analysis. Fuzzy synthetical evaluation other fields is employed to evaluate the project. Its evaluation system and method is introduced and Delphi method is adopted to obtain evaluation index. Finally, taking Harbin city as an example, the application process of above-mentioned method is illuminated. Accordingly, it is proved that the method is exercisable.
文摘Previously,we had identified the various dynamic mechanisms of a wide range air to fuel ratio sensor operated in the engine exhaust by using the transfer function approach.In this study,we utilized these results to model the real time sensor response to an engine exhaust excursion.In the fitting,we identified a new dynamic mechanism,which was not detected in the previous transfer function study.This new dynamic occurred at the stoichiometric point when the engine changed from rich to lean.This new mechanism involved the depletion of the adsorbed fuel species on the electrode surface by an oxidation process. The dynamics of this effect depends on the ratio of the diffusion flux of the sensor-coating layer to the total adsorbed gas species on the electrode surface.The smaller the ratio is,the slower the dynamic mechanism will be.
文摘The conceptual design of mechatronic systems is addressed under the thrust of concurrent engineering and an enhanced conceptual design methodology describing the early design stage of mechatronic systems is presented through an example illustration of a pick and place robot.This methodology treats each feasible solution as a solution strategy.In the methodology,Quality Function Deployment(QFD)is used as a baseline for the analysis of the mapping from customers to engineering requirements,Axiomatic Design(AD)is adopted as a guideline to generate feasible,good design solution alternatives,and Theory of Inventive Problem Solving(TRIZ)is applied to deal with domain conflicts in design.
文摘Novel plastics that are biodegradable, environmentally benign, and made from renewable natural resources are currently being researched as alternatives to traditional petroleum-based plastics. One such plastic, thermoplastic starch (TPS) is produced from starch processed at high temperatures in the presence of plasticizers, such as water and glycerol. However, because of its hydrophilic nature, TPS exhibits poor mechanical properties when exposed to environmental conditions, such as rain or humidity. The overall objective of this research work was to produce a thermoplastic starch based material with low water absorption that may be used to replace petroleum-based plastics. With a recent emergence of “green” polyethylene (GPE), sourced from renewable feedstock, it has become possible to develop novel biodegradable polymers for various applications. In this work, GPE was melt blended with starch in three different ways;reactive extrusion of GPE and starch facilitated by maleic anhydride (MAH) and dicumyl peroxide (DCP), melt blending of GPE and starch by extrusion, and melt blending of maleated polyethylene and starch by extrusion. Comprehensive testing and analysis has shown that all methods reduced water absorption significantly with some variations across the board.