This paper analyzes conflict features in architecture pipe routing,and builds a pipe routing design conflict model by taking into account of discrete nominal internal diameter selection of pipes,material costs,and con...This paper analyzes conflict features in architecture pipe routing,and builds a pipe routing design conflict model by taking into account of discrete nominal internal diameter selection of pipes,material costs,and conflict solution sequence.Considering pipe routing as an assembling process,a conflict detection approach for pipe routing in collaborative architectural design is proposed based on an aforementioned model.Constraint network is used to describe the relationship among pipe routing design parameters and constraints;design conflicts are detected by matching designers' input and constraint network;and detected design conflicts are reordered according to the number of pipe parameters in conflicts.In order to support the collaborative requirement of pipe routing design,a prototype system using browser/server architecture is developed.An illustrative example of water pipe routing in a room is used to show the effectiveness and efficiency of the approach.展开更多
In the design of the integrated circuits, in order to ensure that the designed products conform to the presupposed parameters, while designing the schematic diagrams of the circuits, we should also strengthen the layo...In the design of the integrated circuits, in order to ensure that the designed products conform to the presupposed parameters, while designing the schematic diagrams of the circuits, we should also strengthen the layout design. Especially in the design of the analog circuits, in the layout design, there is a high degree of matching requirement for the MOS. It will have an important impact on the performance of the chips. Based on this perspective, the author of this paper analyzes how to realize the matching of the three aspects of the MOS, the resistance and the capacitance in the integrated circuit design, in order to avoid the problem of the mismatch due to the arts and crafts.展开更多
In the trust management scheme of the distributed cognitive radio networks, the absence of the central control devices cause many problems such as a lack of standardized control for trust computation, and the absence ...In the trust management scheme of the distributed cognitive radio networks, the absence of the central control devices cause many problems such as a lack of standardized control for trust computation, and the absence of the decision makers in trust evaluation and collaborative decision making. A trust management mechanism based on the jury system for distributed cognitive radio networks is proposed in this paper. The "jury user" is designed to collaboratively examine the reputation of the cognitive user in the networks and to perform data fusion and spectrum allocation for distributed cognitive radio networks. Simulation analysis results show that the proposed scheme can ensure accuracy and fairness in trust evaluation and improve effectiveness and flexibility of spectrum allocation.展开更多
We have investigated the distribution of the electric field in p-i-n GaN avalanche photodiodes under different reverse bias values. type and separate absorption and multiplication （SAM） type We have also analyzed th...We have investigated the distribution of the electric field in p-i-n GaN avalanche photodiodes under different reverse bias values. type and separate absorption and multiplication （SAM） type We have also analyzed the influences of the parameters of each layer, including width and concentration, on the distribution of the electric field, especially on the breakdown voltage. It is found that a relatively high concentration of p-GaN （higher than 1×10^18 cm-3） and low cartier concentration of i-GaN （lower than 5×1016 cm-3） are helpful to restrict the electric field and reduce the breakdown voltage. In a SAM （p-i-n-i-n） structure, a suitable choice should be made for the concentration and thickness of the intermediate n-GaN layer in order to decrease breakdown voltage and prevent the device from degenerating into a p-i-n structure. Finally, the optimized material parameters of each layer are proposed.展开更多
基金Supported by the National High Technology Research and Development Programme of China(No.2006AA04Z112)the National Natural Science Foundation of China(No.51175287)the National S&T Major Program(No.2009ZX02001-003)
文摘This paper analyzes conflict features in architecture pipe routing,and builds a pipe routing design conflict model by taking into account of discrete nominal internal diameter selection of pipes,material costs,and conflict solution sequence.Considering pipe routing as an assembling process,a conflict detection approach for pipe routing in collaborative architectural design is proposed based on an aforementioned model.Constraint network is used to describe the relationship among pipe routing design parameters and constraints;design conflicts are detected by matching designers' input and constraint network;and detected design conflicts are reordered according to the number of pipe parameters in conflicts.In order to support the collaborative requirement of pipe routing design,a prototype system using browser/server architecture is developed.An illustrative example of water pipe routing in a room is used to show the effectiveness and efficiency of the approach.
文摘In the design of the integrated circuits, in order to ensure that the designed products conform to the presupposed parameters, while designing the schematic diagrams of the circuits, we should also strengthen the layout design. Especially in the design of the analog circuits, in the layout design, there is a high degree of matching requirement for the MOS. It will have an important impact on the performance of the chips. Based on this perspective, the author of this paper analyzes how to realize the matching of the three aspects of the MOS, the resistance and the capacitance in the integrated circuit design, in order to avoid the problem of the mismatch due to the arts and crafts.
基金supported by the National Natural Science Foundation of China under Grant No. 61172068
文摘In the trust management scheme of the distributed cognitive radio networks, the absence of the central control devices cause many problems such as a lack of standardized control for trust computation, and the absence of the decision makers in trust evaluation and collaborative decision making. A trust management mechanism based on the jury system for distributed cognitive radio networks is proposed in this paper. The "jury user" is designed to collaboratively examine the reputation of the cognitive user in the networks and to perform data fusion and spectrum allocation for distributed cognitive radio networks. Simulation analysis results show that the proposed scheme can ensure accuracy and fairness in trust evaluation and improve effectiveness and flexibility of spectrum allocation.
基金supported by the National Science Fund for Distinguished Young Scholars (Grant No. 60925017)the National Natural Science Foundation of China (Grant Nos. 10990100,60836003 and 60776047)
文摘We have investigated the distribution of the electric field in p-i-n GaN avalanche photodiodes under different reverse bias values. type and separate absorption and multiplication （SAM） type We have also analyzed the influences of the parameters of each layer, including width and concentration, on the distribution of the electric field, especially on the breakdown voltage. It is found that a relatively high concentration of p-GaN （higher than 1×10^18 cm-3） and low cartier concentration of i-GaN （lower than 5×1016 cm-3） are helpful to restrict the electric field and reduce the breakdown voltage. In a SAM （p-i-n-i-n） structure, a suitable choice should be made for the concentration and thickness of the intermediate n-GaN layer in order to decrease breakdown voltage and prevent the device from degenerating into a p-i-n structure. Finally, the optimized material parameters of each layer are proposed.
