In order to meet the needs of higher operation speed and lower energy consumption an optimized SHA-1 algorithm is proposed.It combines two methods loop-unfolding and pre-processing.In the process intermediate variable...In order to meet the needs of higher operation speed and lower energy consumption an optimized SHA-1 algorithm is proposed.It combines two methods loop-unfolding and pre-processing.In the process intermediate variables are introduced in the iterations and pre-calculated so that the original single-threading operation can perform in a multi-threading way.This optimized algorithm exploits parallelism to shorten the critical path for hash operations.And the cycles of the original algorithm are reduced from 80 to 41 which greatly improves the operation speed.Therefore the shortened iterations of the optimized design require a smaller amount of hardware resource thus achieving a lower energy consumption. The optimized algorithm is implemented on FPGA field programmable gate array .It can achieve a throughput rate of 1.2 Gbit /s with the maximum clock frequency of 91 MHz reaching a fair balance between operation speed and throughput rate.The simulation results show that compared with other optimized SHA-1 algorithms this algorithm obtains higher operation speed and throughput rate without compromising the security of the original SHA-1 algorithm.展开更多
In this paper,quadratic 0-1 programming problem (I) is considered, in terms of its features quadratic 0-1 programming problem is solved by linear approxity heurstic algrothm and a developed tabu search ahgrothm .
Special solution of the （2＋1）-dimensional Sawada Kotera equation is decomposed into three （0＋1）- dimensional Bargmann flows. They are straightened out on the Jacobi variety of the associated hyperelliptic curve....Special solution of the （2＋1）-dimensional Sawada Kotera equation is decomposed into three （0＋1）- dimensional Bargmann flows. They are straightened out on the Jacobi variety of the associated hyperelliptic curve. Explicit algebraic-geometric solution is obtained on the basis of a deeper understanding of the KdV hierarchy.展开更多
In this paper an error in[4]is pointed out and a method for constructingsurface interpolating scattered data points is presented.The main feature of the methodin this paper is that the surface so constructed is polyno...In this paper an error in[4]is pointed out and a method for constructingsurface interpolating scattered data points is presented.The main feature of the methodin this paper is that the surface so constructed is polynomial,which makes the construction simple and the calculation easy.展开更多
An Efficient and flexible implementation of block ciphers is critical to achieve information security processing.Existing implementation methods such as GPP,FPGA and cryptographic application-specific ASIC provide the...An Efficient and flexible implementation of block ciphers is critical to achieve information security processing.Existing implementation methods such as GPP,FPGA and cryptographic application-specific ASIC provide the broad range of support.However,these methods could not achieve a good tradeoff between high-speed processing and flexibility.In this paper,we present a reconfigurable VLIW processor architecture targeted at block cipher processing,analyze basic operations and storage characteristics,and propose the multi-cluster register-file structure for block ciphers.As for the same operation element of block ciphers,we adopt reconfigurable technology for multiple cryptographic processing units and interconnection scheme.The proposed processor not only flexibly accomplishes the combination of multiple basic cryptographic operations,but also realizes dynamic configuration for cryptographic processing units.It has been implemented with0.18μm CMOS technology,the test results show that the frequency can reach 350 MHz.and power consumption is 420 mw.Ten kinds of block and hash ciphers were realized in the processor.The encryption throughput of AES,DES,IDEA,and SHA-1 algorithm is1554 Mbps,448Mbps,785 Mbps,and 424 Mbps respectively,the test result shows that our processor's encryption performance is significantly higher than other designs.展开更多
In order to balance the temporal-spatial distribution of urban traffic flow, a model is established for combined urban traffic signal control and traffic flow guidance. With consideration of the wide use of fixed sign...In order to balance the temporal-spatial distribution of urban traffic flow, a model is established for combined urban traffic signal control and traffic flow guidance. With consideration of the wide use of fixed signal control at intersections, traffic assignment under traffic flow guidance, and dynamic characteristics of urban traffic management, a tri-level programming model is presented. To reflect the impact of intersection delay on traffic assignment, the lower level model is set as a modified user equilibrium model. The middle level model, which contains several definitional constraints for different phase modes, is built for the traffic signal control optimization. To solve the problem of tide lane management, the upper level model is built up based on nonlinear 0-1 integer programming. A heuristic iterative optimization algorithm(HIOA) is set up to solve the tri-level programming model. The lower level model is solved by method of successive averages(MSA), the middle level model is solved by non-dominated sorting genetic algorithm II(NSGA II), and the upper level model is solved by genetic algorithm(GA). A case study is raised to show the efficiency and applicability of the proposed modelling and computing method.展开更多
In this paper, we construct two models for the searching task for a lost plane. Model 1 determines the searching area. We predict the trajectory of floats generated after the disintegration of the plane by using RBF n...In this paper, we construct two models for the searching task for a lost plane. Model 1 determines the searching area. We predict the trajectory of floats generated after the disintegration of the plane by using RBF neural network model, and then determine the searching area according to the trajectory. With the pass of time, the searching area will also be constantly moving along the trajectory. Model 2 develops a maritime search plan to achieve the purpose of completing the search in the shortest time. We optimize the searching time and transform the problem into the 0-1 knapsack problem. Solving this problem by improved genetic algorithm, we can get the shortest searching time and the best choice for the search power.展开更多
In this paper we study a queueing system with state-dependent services and state-dependent vacations, or simply G/M（n）/1/K. Since the service rate is state-dependent, this system includes G/M/c and G/M/c/K queues wi...In this paper we study a queueing system with state-dependent services and state-dependent vacations, or simply G/M（n）/1/K. Since the service rate is state-dependent, this system includes G/M/c and G/M/c/K queues with various types of station vacations as special cases. We provide a recursive algorithm using the supplementary variable technique to numerically compute the stationary queue length distribution of the system. The only input requirement is the Laplace-Stieltjes transform of the interarrival distribution as well as the state-dependent service rate and state-dependent vacation rate. In a subsequent companion paper, we study its dual system M（n）/G/1/K queue with statedependent vacations.展开更多
We study a single-server queueing system with state-dependent arrivals and general service distribution, or simply M（n）/G/1/K, where the server follows an N policy and takes multiple vacations when the system is emp...We study a single-server queueing system with state-dependent arrivals and general service distribution, or simply M（n）/G/1/K, where the server follows an N policy and takes multiple vacations when the system is empty. We provide a recursive algorithm using the supplementary variable technique to numerically compute the stationary queue length distribution of the system. The only input requirements are the Laplace-Stieltjes transforms of the service time distribution and the vacation time distribution, and the state-dependent arrival rate. The computational complexity of the algorithm is O（K^3）.展开更多
基金The Project of Wireless Intelligence Terminal Inspection Services(No.6704000084)the Special Program of the NationalDevelopment and Reform Committee
文摘In order to meet the needs of higher operation speed and lower energy consumption an optimized SHA-1 algorithm is proposed.It combines two methods loop-unfolding and pre-processing.In the process intermediate variables are introduced in the iterations and pre-calculated so that the original single-threading operation can perform in a multi-threading way.This optimized algorithm exploits parallelism to shorten the critical path for hash operations.And the cycles of the original algorithm are reduced from 80 to 41 which greatly improves the operation speed.Therefore the shortened iterations of the optimized design require a smaller amount of hardware resource thus achieving a lower energy consumption. The optimized algorithm is implemented on FPGA field programmable gate array .It can achieve a throughput rate of 1.2 Gbit /s with the maximum clock frequency of 91 MHz reaching a fair balance between operation speed and throughput rate.The simulation results show that compared with other optimized SHA-1 algorithms this algorithm obtains higher operation speed and throughput rate without compromising the security of the original SHA-1 algorithm.
文摘In this paper,quadratic 0-1 programming problem (I) is considered, in terms of its features quadratic 0-1 programming problem is solved by linear approxity heurstic algrothm and a developed tabu search ahgrothm .
基金The project supported by the Special Funds for Major State Basic Research Project under Grant No.G2000077301
文摘Special solution of the （2＋1）-dimensional Sawada Kotera equation is decomposed into three （0＋1）- dimensional Bargmann flows. They are straightened out on the Jacobi variety of the associated hyperelliptic curve. Explicit algebraic-geometric solution is obtained on the basis of a deeper understanding of the KdV hierarchy.
文摘In this paper an error in[4]is pointed out and a method for constructingsurface interpolating scattered data points is presented.The main feature of the methodin this paper is that the surface so constructed is polynomial,which makes the construction simple and the calculation easy.
基金supported by National Natural Science Foundation of China with granted No.61404175
文摘An Efficient and flexible implementation of block ciphers is critical to achieve information security processing.Existing implementation methods such as GPP,FPGA and cryptographic application-specific ASIC provide the broad range of support.However,these methods could not achieve a good tradeoff between high-speed processing and flexibility.In this paper,we present a reconfigurable VLIW processor architecture targeted at block cipher processing,analyze basic operations and storage characteristics,and propose the multi-cluster register-file structure for block ciphers.As for the same operation element of block ciphers,we adopt reconfigurable technology for multiple cryptographic processing units and interconnection scheme.The proposed processor not only flexibly accomplishes the combination of multiple basic cryptographic operations,but also realizes dynamic configuration for cryptographic processing units.It has been implemented with0.18μm CMOS technology,the test results show that the frequency can reach 350 MHz.and power consumption is 420 mw.Ten kinds of block and hash ciphers were realized in the processor.The encryption throughput of AES,DES,IDEA,and SHA-1 algorithm is1554 Mbps,448Mbps,785 Mbps,and 424 Mbps respectively,the test result shows that our processor's encryption performance is significantly higher than other designs.
基金Project(2014BAG01B0403)supported by the High-Tech Research and Development Program of China
文摘In order to balance the temporal-spatial distribution of urban traffic flow, a model is established for combined urban traffic signal control and traffic flow guidance. With consideration of the wide use of fixed signal control at intersections, traffic assignment under traffic flow guidance, and dynamic characteristics of urban traffic management, a tri-level programming model is presented. To reflect the impact of intersection delay on traffic assignment, the lower level model is set as a modified user equilibrium model. The middle level model, which contains several definitional constraints for different phase modes, is built for the traffic signal control optimization. To solve the problem of tide lane management, the upper level model is built up based on nonlinear 0-1 integer programming. A heuristic iterative optimization algorithm(HIOA) is set up to solve the tri-level programming model. The lower level model is solved by method of successive averages(MSA), the middle level model is solved by non-dominated sorting genetic algorithm II(NSGA II), and the upper level model is solved by genetic algorithm(GA). A case study is raised to show the efficiency and applicability of the proposed modelling and computing method.
文摘In this paper, we construct two models for the searching task for a lost plane. Model 1 determines the searching area. We predict the trajectory of floats generated after the disintegration of the plane by using RBF neural network model, and then determine the searching area according to the trajectory. With the pass of time, the searching area will also be constantly moving along the trajectory. Model 2 develops a maritime search plan to achieve the purpose of completing the search in the shortest time. We optimize the searching time and transform the problem into the 0-1 knapsack problem. Solving this problem by improved genetic algorithm, we can get the shortest searching time and the best choice for the search power.
基金supported by National Science Foundation under DMI-0200306supported in part by a grant from National Natural Science Foundation of China under No.70228001.
文摘In this paper we study a queueing system with state-dependent services and state-dependent vacations, or simply G/M（n）/1/K. Since the service rate is state-dependent, this system includes G/M/c and G/M/c/K queues with various types of station vacations as special cases. We provide a recursive algorithm using the supplementary variable technique to numerically compute the stationary queue length distribution of the system. The only input requirement is the Laplace-Stieltjes transform of the interarrival distribution as well as the state-dependent service rate and state-dependent vacation rate. In a subsequent companion paper, we study its dual system M（n）/G/1/K queue with statedependent vacations.
基金partially supported by National Science Foundation under DMI-0200306supported in part by a grant from National Natural Science Foundation of China under No.70228001.
文摘We study a single-server queueing system with state-dependent arrivals and general service distribution, or simply M（n）/G/1/K, where the server follows an N policy and takes multiple vacations when the system is empty. We provide a recursive algorithm using the supplementary variable technique to numerically compute the stationary queue length distribution of the system. The only input requirements are the Laplace-Stieltjes transforms of the service time distribution and the vacation time distribution, and the state-dependent arrival rate. The computational complexity of the algorithm is O（K^3）.
