The Internet is becoming increasingly more valuable in the field ofarchitectural design so that what we conventionally called CAD might soon be changed to Internetaided design (iAD). In order to have a clear vision of...The Internet is becoming increasingly more valuable in the field ofarchitectural design so that what we conventionally called CAD might soon be changed to Internetaided design (iAD). In order to have a clear vision of what IAD will be or could be, we should firstexamine what is currently available. This research focuses on an investigation of selected Webvendors, which are typical and most influential in providing Internet related services for the AECindustry. By comparing and analyzing their functionality, services provided, business models,technology and financial situation, we have seen that Internet application in the AEC industry isstill in early stage, especially in the area of on-line engineering consulting for architects.展开更多
The goal of web service composition is to choose an optimal scheme according to Quantity of Service （QoS） which selects instances in a distributed network. The networks are clustered with some web services such as o...The goal of web service composition is to choose an optimal scheme according to Quantity of Service （QoS） which selects instances in a distributed network. The networks are clustered with some web services such as ontologies, algorithms and rule engines with similar function and interfaces. In this scheme, web services acted as candidate service construct a distributed model which can＇t obtain the global services＇ information. The model is utilized to choose instances according to local QoS information in the progress of service composition. Some QoS matrixes are used to record and compare the instance paths and then choose a better one. Simulation result has proven that our ~pproach has a tradeoff between efficiency and ~quality.展开更多
Rapid developments in network systems of business service have resulted in more reliance on distributed computing, typified by “subscriber/push” architectures. Unfortunately, frequent and unexpectable network failur...Rapid developments in network systems of business service have resulted in more reliance on distributed computing, typified by “subscriber/push” architectures. Unfortunately, frequent and unexpectable network failures were routine, and downtime was not in hours, but in days. High availability has become the most important factor decreasing business risk and improving Quality of Service. Cluster technology has solved the non-stop problem on Local Area Network. However, most technologies including cluster today fail to ensure the non-stop Internet service based on Routers. With good performance on high availability and fault tolerance, quorum systems are very suitable for application to distributed business service networks. In this work, we modeled and developed a non-stop Internet service system based on a new quorum system, circle quorum system, for Boston Mutual Fund Broker, US. With five protocols, it provided highly available data services for clients on Internet.展开更多
Low Earth Orbit （LEO） satellites networks can provide multimedia service and plays an increasingly important role in the exploitation of space. However, one of the challenges in LEO satellites networks is that the s...Low Earth Orbit （LEO） satellites networks can provide multimedia service and plays an increasingly important role in the exploitation of space. However, one of the challenges in LEO satellites networks is that the services are suffered from high symbol error, limited storage space and limited available energy. To analyze the performance of the service in LEO satellites networks, a model, based on differential game, is proposed for satisfying the QoS requirements of multimedia applications. The controller of our model is the transmitting rate and the object is to maximize the payoff depending on the error symbol rate, the available energy, the bandwidth and the process ability so as to guarantee the QoS service. In order to solve our built model, we use the Bellman theorem to make formulas on the trance of the optimal transmitting rate. Furthermore, simulation results verify that the service can be maximized by using our derived transmitting rate trance.展开更多
文摘The Internet is becoming increasingly more valuable in the field ofarchitectural design so that what we conventionally called CAD might soon be changed to Internetaided design (iAD). In order to have a clear vision of what IAD will be or could be, we should firstexamine what is currently available. This research focuses on an investigation of selected Webvendors, which are typical and most influential in providing Internet related services for the AECindustry. By comparing and analyzing their functionality, services provided, business models,technology and financial situation, we have seen that Internet application in the AEC industry isstill in early stage, especially in the area of on-line engineering consulting for architects.
基金National Natural Science Foundation of China，Major National Science and Technology Projects of New Generation Broadband Wireless Mobile Communication Network，the National High Technology Research and Development Program of China (863 Program)
文摘The goal of web service composition is to choose an optimal scheme according to Quantity of Service （QoS） which selects instances in a distributed network. The networks are clustered with some web services such as ontologies, algorithms and rule engines with similar function and interfaces. In this scheme, web services acted as candidate service construct a distributed model which can＇t obtain the global services＇ information. The model is utilized to choose instances according to local QoS information in the progress of service composition. Some QoS matrixes are used to record and compare the instance paths and then choose a better one. Simulation result has proven that our ~pproach has a tradeoff between efficiency and ~quality.
文摘Rapid developments in network systems of business service have resulted in more reliance on distributed computing, typified by “subscriber/push” architectures. Unfortunately, frequent and unexpectable network failures were routine, and downtime was not in hours, but in days. High availability has become the most important factor decreasing business risk and improving Quality of Service. Cluster technology has solved the non-stop problem on Local Area Network. However, most technologies including cluster today fail to ensure the non-stop Internet service based on Routers. With good performance on high availability and fault tolerance, quorum systems are very suitable for application to distributed business service networks. In this work, we modeled and developed a non-stop Internet service system based on a new quorum system, circle quorum system, for Boston Mutual Fund Broker, US. With five protocols, it provided highly available data services for clients on Internet.
基金National Science Foundation Project of P.R.China，China Postdoctoral Science Foundation
文摘Low Earth Orbit （LEO） satellites networks can provide multimedia service and plays an increasingly important role in the exploitation of space. However, one of the challenges in LEO satellites networks is that the services are suffered from high symbol error, limited storage space and limited available energy. To analyze the performance of the service in LEO satellites networks, a model, based on differential game, is proposed for satisfying the QoS requirements of multimedia applications. The controller of our model is the transmitting rate and the object is to maximize the payoff depending on the error symbol rate, the available energy, the bandwidth and the process ability so as to guarantee the QoS service. In order to solve our built model, we use the Bellman theorem to make formulas on the trance of the optimal transmitting rate. Furthermore, simulation results verify that the service can be maximized by using our derived transmitting rate trance.
