A path-based timing optimization algorithm for buffer insertion and simultaneous sizing is proposed. Firstly, candidate buffer insertion location and buffer size for each branch in a given routing path were obtained v...A path-based timing optimization algorithm for buffer insertion and simultaneous sizing is proposed. Firstly, candidate buffer insertion location and buffer size for each branch in a given routing path were obtained via localized timing optimization. Then, through evaluating each potential insertion against design objectives, potential optimal buffer insertion locations and sizes for the whole routing tree were determined. At last, by removing redundant buffer insertion operations which do not maximize S （ so ）, given timing requirements are finally fulfilled through minimum number of buffers.展开更多
We investigate the similarities and differences among three queue rules,the first-in-first-out(FIFO)rule,last-in-firstout(LIFO)rule and random-in-random-out(RIRO)rule,on dynamical networks with limited buffer size.In ...We investigate the similarities and differences among three queue rules,the first-in-first-out(FIFO)rule,last-in-firstout(LIFO)rule and random-in-random-out(RIRO)rule,on dynamical networks with limited buffer size.In our network model,nodes move at each time step.Packets are transmitted by an adaptive routing strategy,combining Euclidean distance and node load by a tunable parameter.Because of this routing strategy,at the initial stage of increasing buffer size,the network density will increase,and the packet loss rate will decrease.Packet loss and traffic congestion occur by these three rules,but nodes keep unblocked and lose no packet in a larger buffer size range on the RIRO rule networks.If packets are lost and traffic congestion occurs,different dynamic characteristics are shown by these three queue rules.Moreover,a phenomenon similar to Braess’paradox is also found by the LIFO rule and the RIRO rule.展开更多
The ordered event model is improved to describe serial production lines with limited buffer sizes. The improved model hasthe same computational burden as the original one and can be constrUcted directly according to g...The ordered event model is improved to describe serial production lines with limited buffer sizes. The improved model hasthe same computational burden as the original one and can be constrUcted directly according to given principles. Several simulationexamples are cited to verify this improved model. Extensions and open problems are also indicated. By means of this new model, serialProduotion lines with limitations of resources can be stUdied analytically.展开更多
Jitter is one of the most important issues for multimedia real time services in future mobile ad hoc networks（MANET）. A thorough theoretical analysis of the destination buffer for smoothing the jitter of the real ti...Jitter is one of the most important issues for multimedia real time services in future mobile ad hoc networks（MANET）. A thorough theoretical analysis of the destination buffer for smoothing the jitter of the real time service in MANET is given. The theoretical results are applied in moderate populated ad hoc networks in our simulation, the simulation results show that by predicting and adjusting destination buffer in our way, Jitter will be alleviated in large part and this will contribute much to the quality of service （QOS） in MANET.展开更多
To increase the performance of bulk data transfer mission with ultra-long TCP （ transmission control protocol） connection in high-energy physics experiments, a series of experiments were conducted to explore the way...To increase the performance of bulk data transfer mission with ultra-long TCP （ transmission control protocol） connection in high-energy physics experiments, a series of experiments were conducted to explore the way to enhance the transmission efficiency. This paper introduces the overall structure of RC@ SEU （ regional center @ Southeast University） in AMS （alpha magnetic spectrometer）-02 ground data transfer system as well as the experiments conducted in CERNET （China Education and Research Network）/CERNET2 and global academic Internet. The effects of the number of parallel streams and TCP buffer size are tested. The test confirms that in the current circumstance of CERNET, to find the fight number of parallel TCP connections is the main method to improve the throughput. TCP buffer size tuning has little effect now, but may have good effects when the available bandwidth becomes higher.展开更多
In this paper we propose a COncurrent Production Engineering System （COPES） for the flexible transfer line （FTL） layout design in a restricted area. COPES first determines the buffer size in front of the bay of ea...In this paper we propose a COncurrent Production Engineering System （COPES） for the flexible transfer line （FTL） layout design in a restricted area. COPES first determines the buffer size in front of the bay of each machine tool in the FTL and then initializes a computer aided design （CAD） system to draw the FTL in a restricted area. We develop a set of modules systems which have been integrated into a single framework, in accordance with the practice of concurrent engineering. Concurrent engineering involves the cooperation of these activities. It＇s expected that the developed COPES can improve the cooperation between production engineers＇ and the plant designer. This can be done by enabling the production engineers＇ to make better decision regarding FTL buffer size.展开更多
文摘A path-based timing optimization algorithm for buffer insertion and simultaneous sizing is proposed. Firstly, candidate buffer insertion location and buffer size for each branch in a given routing path were obtained via localized timing optimization. Then, through evaluating each potential insertion against design objectives, potential optimal buffer insertion locations and sizes for the whole routing tree were determined. At last, by removing redundant buffer insertion operations which do not maximize S （ so ）, given timing requirements are finally fulfilled through minimum number of buffers.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.71801066 and 71431003)the Fundamental Research Funds for the Central Universities of China(Grant Nos.PA2019GDQT0020 and JZ2017HGTB0186)
文摘We investigate the similarities and differences among three queue rules,the first-in-first-out(FIFO)rule,last-in-firstout(LIFO)rule and random-in-random-out(RIRO)rule,on dynamical networks with limited buffer size.In our network model,nodes move at each time step.Packets are transmitted by an adaptive routing strategy,combining Euclidean distance and node load by a tunable parameter.Because of this routing strategy,at the initial stage of increasing buffer size,the network density will increase,and the packet loss rate will decrease.Packet loss and traffic congestion occur by these three rules,but nodes keep unblocked and lose no packet in a larger buffer size range on the RIRO rule networks.If packets are lost and traffic congestion occurs,different dynamic characteristics are shown by these three queue rules.Moreover,a phenomenon similar to Braess’paradox is also found by the LIFO rule and the RIRO rule.
文摘The ordered event model is improved to describe serial production lines with limited buffer sizes. The improved model hasthe same computational burden as the original one and can be constrUcted directly according to given principles. Several simulationexamples are cited to verify this improved model. Extensions and open problems are also indicated. By means of this new model, serialProduotion lines with limitations of resources can be stUdied analytically.
文摘Jitter is one of the most important issues for multimedia real time services in future mobile ad hoc networks（MANET）. A thorough theoretical analysis of the destination buffer for smoothing the jitter of the real time service in MANET is given. The theoretical results are applied in moderate populated ad hoc networks in our simulation, the simulation results show that by predicting and adjusting destination buffer in our way, Jitter will be alleviated in large part and this will contribute much to the quality of service （QOS） in MANET.
基金The National Basic Research Program of China (973Program) (No.2003CB314803).
文摘To increase the performance of bulk data transfer mission with ultra-long TCP （ transmission control protocol） connection in high-energy physics experiments, a series of experiments were conducted to explore the way to enhance the transmission efficiency. This paper introduces the overall structure of RC@ SEU （ regional center @ Southeast University） in AMS （alpha magnetic spectrometer）-02 ground data transfer system as well as the experiments conducted in CERNET （China Education and Research Network）/CERNET2 and global academic Internet. The effects of the number of parallel streams and TCP buffer size are tested. The test confirms that in the current circumstance of CERNET, to find the fight number of parallel TCP connections is the main method to improve the throughput. TCP buffer size tuning has little effect now, but may have good effects when the available bandwidth becomes higher.
文摘In this paper we propose a COncurrent Production Engineering System （COPES） for the flexible transfer line （FTL） layout design in a restricted area. COPES first determines the buffer size in front of the bay of each machine tool in the FTL and then initializes a computer aided design （CAD） system to draw the FTL in a restricted area. We develop a set of modules systems which have been integrated into a single framework, in accordance with the practice of concurrent engineering. Concurrent engineering involves the cooperation of these activities. It＇s expected that the developed COPES can improve the cooperation between production engineers＇ and the plant designer. This can be done by enabling the production engineers＇ to make better decision regarding FTL buffer size.
