The maintenance window scheme(MWS) is one of the most important railway transportation organizational plans and plays an important role in ensuring railway operational safety. However, MWS setting is a very complicate...The maintenance window scheme(MWS) is one of the most important railway transportation organizational plans and plays an important role in ensuring railway operational safety. However, MWS setting is a very complicated process, and most countries currently do so with the help of a computer-aided decision system. In general, a decision system can generate multiple alternatives for MWS within an acceptable time. Therefore, how to choose the best option from the alternatives is a vital decision. This paper presents a novel framework for MWS evaluation based on the Chinese railway system. Specifically, the requirements of each department related to MWS setting are analysed, and we construct an evaluation indicator system for MWS based on the preferences of different departments. Then, we apply the fuzzy soft set theory to MWS evaluation, a method that not only effectively deals with evaluation of uncertain information, but also gives flexibility for experts to input their subjective judgment.Additionally, using the ‘‘AND’’ operation of soft set theory allows combing evaluation information from multiple evaluators to give comprehensive results. Finally, a case study illustrates the proposed framework, showing that the proposed evaluation indicator system and evaluation method are effective and practical.展开更多
The kinetic and thermodynamic structure of typhoon Rammasun (No. 0205) over the Northwest Pacific has been analyzed, using NOAA-16 polar orbiting Advanced Microwave Sounding Unit (AMSU) data collected on 2 July, 2002....The kinetic and thermodynamic structure of typhoon Rammasun (No. 0205) over the Northwest Pacific has been analyzed, using NOAA-16 polar orbiting Advanced Microwave Sounding Unit (AMSU) data collected on 2 July, 2002. The three-dimensional variational (3DVAR) assimila-tion technology is used to assimilate the satellite observation. The results show that the characteristics of the 3D typhoon structure can be more reasonably described from the assimi-lated data. The warm-cored structure of the typhoon is en-hanced in the analyzed field, which corresponds to strong typhoon. The typhoon cyclonic circulation in the middle and lower layers is apparently strengthened, and the strong anti-cyclonic circulation appears at the top of the typhoon. The water vapor and its supply in the typhoon are enhanced. The microwave assimilation data may be used to supply the lack of the conventional observation data over the tropical ocean.展开更多
A Neural Network( NN ) approach to ABR flow control algorithm in ATM networks is proposed. The NN predicts the queue length, its variation and possible cell loss, then regulates the source rate adaptivel...A Neural Network( NN ) approach to ABR flow control algorithm in ATM networks is proposed. The NN predicts the queue length, its variation and possible cell loss, then regulates the source rate adaptively. Therefore, more appropriate value of the explicit rate can be determined in the corresponding field of the RM cells. This approach performs better than the traditional static feedback control. Additionally, the performance of this algorithm under CBR background traffic is discussed, and the simulatino results show that the neural network is also efficient.展开更多
This paper proposes a Shared Buffer Memory ATM Access Switch . The switches have significant benefits over Crossbar or Bus Based switches because its output buffer memories are shared by all the switch output ports an...This paper proposes a Shared Buffer Memory ATM Access Switch . The switches have significant benefits over Crossbar or Bus Based switches because its output buffer memories are shared by all the switch output ports and are allotted to one particular output port as the occasion demands. As Buffer allocation schemes in the ATM Switches is Partial Sharing, it is trade-off between Complete Sharing and Dedicated Allocation. In addition, the queuing structures used in the shared memory are independent of both the data path through the switch and the cell scheduling mechanism. The method for queue management is simple and effective.展开更多
In this paper, orthogonal/turbo-codes for mobile DS-CDMA communications are considered. We compare the performances of turbo-codes with those of convolutional codes for noncoherent M-ary orthogonal modulation in ...In this paper, orthogonal/turbo-codes for mobile DS-CDMA communications are considered. We compare the performances of turbo-codes with those of convolutional codes for noncoherent M-ary orthogonal modulation in multipath fading channels. One method to calculate the branch transition probability of turbo-codes is suggested.By using the parameter of cut-off rate capacity efficiency, 1/2/5 (37,21) turbo-codes are more efficient for 1/3/9(557,663,711) convolutional codes. Given the same spread gain, turbo-codes will increase system's capacity.If SOVA is used in the decoding for turbo-codes case, the dime-delay caused by turbo-decoding is only 1.2 times of that of convolutional codes. Obviously, turbo-codes show better performances at the cost of the hardware complexity of the encoder and the decoder.展开更多
in this paper ,based on the butlt-in self-test technique to logic circuil ,a nme approach is pro-posed to optimize input probability of digital circuit. After the worst faults are found and their circuitmodel are crea...in this paper ,based on the butlt-in self-test technique to logic circuil ,a nme approach is pro-posed to optimize input probability of digital circuit. After the worst faults are found and their circuitmodel are created the output signals of these models will be compressed by “1” counter. Fault detectprobabilities for the worst faults can be obtained by analyzing compact data. Finally, using the relationbetween the input probability and the fault detect probabilily ,we propose a new algorithm to optimzethe primary input probainlily of the circuit. So the shortest test length can he received.展开更多
This poper presents a new method of estimating and correcting Doppler frequency shift in anM-ary (D)PSK receiver. The performance is discussed. Analytical and simulation results are presentedand the error probability ...This poper presents a new method of estimating and correcting Doppler frequency shift in anM-ary (D)PSK receiver. The performance is discussed. Analytical and simulation results are presentedand the error probability performance of the (D)PSK receiver is evaluated in the presence of the Doppler correction. It is shown from analytical and simulation results for constant Doppler shift that the methodperforms excellently.展开更多
基金supported by the National Natural Science Foundation of China (Project Nos.61273242,61403317)Science and Technology Plan of Sichuan province (Project No.2017015)Service Science and Innovation Key Laboratory of Sichuan Province (KL1701)
文摘The maintenance window scheme(MWS) is one of the most important railway transportation organizational plans and plays an important role in ensuring railway operational safety. However, MWS setting is a very complicated process, and most countries currently do so with the help of a computer-aided decision system. In general, a decision system can generate multiple alternatives for MWS within an acceptable time. Therefore, how to choose the best option from the alternatives is a vital decision. This paper presents a novel framework for MWS evaluation based on the Chinese railway system. Specifically, the requirements of each department related to MWS setting are analysed, and we construct an evaluation indicator system for MWS based on the preferences of different departments. Then, we apply the fuzzy soft set theory to MWS evaluation, a method that not only effectively deals with evaluation of uncertain information, but also gives flexibility for experts to input their subjective judgment.Additionally, using the ‘‘AND’’ operation of soft set theory allows combing evaluation information from multiple evaluators to give comprehensive results. Finally, a case study illustrates the proposed framework, showing that the proposed evaluation indicator system and evaluation method are effective and practical.
文摘The kinetic and thermodynamic structure of typhoon Rammasun (No. 0205) over the Northwest Pacific has been analyzed, using NOAA-16 polar orbiting Advanced Microwave Sounding Unit (AMSU) data collected on 2 July, 2002. The three-dimensional variational (3DVAR) assimila-tion technology is used to assimilate the satellite observation. The results show that the characteristics of the 3D typhoon structure can be more reasonably described from the assimi-lated data. The warm-cored structure of the typhoon is en-hanced in the analyzed field, which corresponds to strong typhoon. The typhoon cyclonic circulation in the middle and lower layers is apparently strengthened, and the strong anti-cyclonic circulation appears at the top of the typhoon. The water vapor and its supply in the typhoon are enhanced. The microwave assimilation data may be used to supply the lack of the conventional observation data over the tropical ocean.
文摘A Neural Network( NN ) approach to ABR flow control algorithm in ATM networks is proposed. The NN predicts the queue length, its variation and possible cell loss, then regulates the source rate adaptively. Therefore, more appropriate value of the explicit rate can be determined in the corresponding field of the RM cells. This approach performs better than the traditional static feedback control. Additionally, the performance of this algorithm under CBR background traffic is discussed, and the simulatino results show that the neural network is also efficient.
文摘This paper proposes a Shared Buffer Memory ATM Access Switch . The switches have significant benefits over Crossbar or Bus Based switches because its output buffer memories are shared by all the switch output ports and are allotted to one particular output port as the occasion demands. As Buffer allocation schemes in the ATM Switches is Partial Sharing, it is trade-off between Complete Sharing and Dedicated Allocation. In addition, the queuing structures used in the shared memory are independent of both the data path through the switch and the cell scheduling mechanism. The method for queue management is simple and effective.
文摘In this paper, orthogonal/turbo-codes for mobile DS-CDMA communications are considered. We compare the performances of turbo-codes with those of convolutional codes for noncoherent M-ary orthogonal modulation in multipath fading channels. One method to calculate the branch transition probability of turbo-codes is suggested.By using the parameter of cut-off rate capacity efficiency, 1/2/5 (37,21) turbo-codes are more efficient for 1/3/9(557,663,711) convolutional codes. Given the same spread gain, turbo-codes will increase system's capacity.If SOVA is used in the decoding for turbo-codes case, the dime-delay caused by turbo-decoding is only 1.2 times of that of convolutional codes. Obviously, turbo-codes show better performances at the cost of the hardware complexity of the encoder and the decoder.
文摘in this paper ,based on the butlt-in self-test technique to logic circuil ,a nme approach is pro-posed to optimize input probability of digital circuit. After the worst faults are found and their circuitmodel are created the output signals of these models will be compressed by “1” counter. Fault detectprobabilities for the worst faults can be obtained by analyzing compact data. Finally, using the relationbetween the input probability and the fault detect probabilily ,we propose a new algorithm to optimzethe primary input probainlily of the circuit. So the shortest test length can he received.
文摘This poper presents a new method of estimating and correcting Doppler frequency shift in anM-ary (D)PSK receiver. The performance is discussed. Analytical and simulation results are presentedand the error probability performance of the (D)PSK receiver is evaluated in the presence of the Doppler correction. It is shown from analytical and simulation results for constant Doppler shift that the methodperforms excellently.
