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面向PKCS的两种大数模运算算法的测试与分析
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作者 邵丽 俞捷 《通信技术》 1996年第1期36-43,共8页
比较分析了两种面向PKCS的快速模运算算法——单表制算法和双表制算法,给出了这两种算法的时空复杂性。着重对这两个算法进行了对比测试。结果表明:双表制算法较单表制算法提高效率30%~50%,同时双表制算法以递推方式建立预计算表... 比较分析了两种面向PKCS的快速模运算算法——单表制算法和双表制算法,给出了这两种算法的时空复杂性。着重对这两个算法进行了对比测试。结果表明:双表制算法较单表制算法提高效率30%~50%,同时双表制算法以递推方式建立预计算表提高了预计算效率180%~490%,为公钥动态管理提供便利;以大数运算在RSA中的应用为例,比较分析出采用双表制算法的加/解密模运算过程较单表制算法的过程提高效率20%~50%。 展开更多
关键词 公钥密码系统 数模运算 算法 测试 分析
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A 59mW 10b 40Msample/s Pipelined ADC 被引量:1
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作者 李建 严杰锋 +4 位作者 陈俊 张剑云 郭亚炜 沈泊 汤庭鳌 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第7期1301-1308,共8页
This paper describes a 3.0V, 10b,40Msample/s analog-to-digital converter (ADC) fabricated in a 0.25μm CMOS technology. Through the sharing an amplifier between two successive pipeline stages, the converter is reali... This paper describes a 3.0V, 10b,40Msample/s analog-to-digital converter (ADC) fabricated in a 0.25μm CMOS technology. Through the sharing an amplifier between two successive pipeline stages, the converter is realized using just four amplifiers with a separate sample-and-hold block. It employs two key techniques: a high bandwidth low-power gain-boosting telescopic amplifiers technique and a low power low offset dynamic comparators technique.The ADC achieves a 8.1 effective number of bits,a maximum differential nonlinearity of a 0.85 least significant bit(LSB), and maximum integral nonlinearity of 2.2LSB for a 0.5MHz input at full sampling rate. It occupies 1.24mm^2 ,which also includes a bandgap and a voltage reference circuit and dissipates only 59mW. 展开更多
关键词 analog-to-digital converter low power OPAMP sharing technique gain-boosting technique
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An 80dB Dynamic Range ΣΔ Modulator for Low-IF GSM Receivers 被引量:1
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作者 杨培 殷秀梅 杨华中 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第2期256-261,共6页
A high-resolution,200kHz signal bandwidth,third-order single-loop single-bit ε△ modulator used in low-IF GSM receivers is presented. The modulator is implemented with fully differential switched capacitor circuits i... A high-resolution,200kHz signal bandwidth,third-order single-loop single-bit ε△ modulator used in low-IF GSM receivers is presented. The modulator is implemented with fully differential switched capacitor circuits in standard 0. 6μm 2P2M CMOS technology. The modulator uses two balanced reference voltages of ±1V,and is driven by a single 26MHz clock signal. The measurement results show that,with an oversampling ratio of 64, the modulator achieves an 80.6dB dynamic range,a 71.8dB peak SNDR,and a 73.9dB peak SNR in the signal bandwidth of 200kHz. The modulator dissipates 15mW static power from a single 5V supply. 展开更多
关键词 sigma-delta modulator analog-to-digital conversion SWITCHED-CAPACITOR operational amplifiers
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Research on the fully fuzzy time-cost trade-off based on genetic algorithms 被引量:1
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作者 JIN Chao-guang JI Zhuo-shang +2 位作者 LIN Yan ZHAO Yuan-min HUANG Zhen-dong 《Journal of Marine Science and Application》 2005年第3期18-23,共6页
It is very difficult to estimate exact values of time and cost of an activity in project scheduling process because many uncertain factors, such as weather, productivity level, human factors etc. , dynamically affect ... It is very difficult to estimate exact values of time and cost of an activity in project scheduling process because many uncertain factors, such as weather, productivity level, human factors etc. , dynamically affect them during project implementation process. A GAs-based fully fuzzy optimal time-cost trade-off model is presented based on fuzzy sets and genetic algorithms (GAs). In tihs model all parameters and variables are characteristics by fuzzy numbers. And then GAs is adopted to search for the optimal solution to this model. The method solves the time-cost trade-off problems under an uncertain environment and is proved practicable through a giving example in ship building scheduling. 展开更多
关键词 fuzzy sets ranking fuzzy number genetic algorithms time-cost trade-off
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Task Assignment Problem of Robots in a Smart Warehouse Environment 被引量:1
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作者 Zhenping Li Wenyu Li Lulu Jiang 《Management Studies》 2016年第4期167-175,共9页
The task assignment problem of robots in a smart warehouse environment (TARSWE) based on cargo-to-person is investigated. Firstly, the sites of warehouse robots and the order picking tasks are given and the task ass... The task assignment problem of robots in a smart warehouse environment (TARSWE) based on cargo-to-person is investigated. Firstly, the sites of warehouse robots and the order picking tasks are given and the task assignment problem for picking one order is formulated into a mathematical model to minimize the total operation cost. Then a heuristic algorithm is designed to solve the task assignment problem for picking multiple orders. Finally, simulations are done by using the orders data of online bookstore A. The results show that using the heuristic algorithm of this paper to assign robots, the cost was reduced by 2% and it can effectively avoid far route and unbalanced workload of robots. The feasibility and validity of the model and algorithm are verified. The model and algorithm in this paper provide a theoretical basis to solve the TARSWE. 展开更多
关键词 smart warehouse ROBOTS cargo-to-person task assignment mathematical model heuristic algorithm
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A novel constant modulus array for multiuser detection
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作者 张继东 郑宝玉 傅洪亮 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第1期38-42,共5页
This paper proposes a new multitarget constant modulus array structure for code division multiple access (CDMA) systems. The new algorithm for the structure is called pre-despreading and wavelet denoising constant mod... This paper proposes a new multitarget constant modulus array structure for code division multiple access (CDMA) systems. The new algorithm for the structure is called pre-despreading and wavelet denoising constant modulus algorithm (D-WD-CMA). In the new algorithm, the pre-despreading is applied to multitarget arrays to remove some multiple access inter- ferences. After that the received signal is subjected to wavelet de-noising to reduce some noise, and used in CMA adaptive iteration for signal separation. Simulation results showed that the proposed algorithm performed better than the traditional CMA algorithm. 展开更多
关键词 Constant modulus algorithm Adaptive array Wavelet de-noising Multiuser detection CDMA
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A systematic approach for synthesizing a low-temperature distillation system 被引量:5
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作者 Yiqing Luo Liang Kong Xigang Yuan 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第5期789-795,共7页
In this paper, by combining a stochastic optimization method with a refrigeration shaft work targeting method,an approach for the synthesis of a heat integrated complex distillation system in a low-temperature process... In this paper, by combining a stochastic optimization method with a refrigeration shaft work targeting method,an approach for the synthesis of a heat integrated complex distillation system in a low-temperature process is presented. The synthesis problem is formulated as a mixed-integer nonlinear programming(MINLP) problem,which is solved by simulated annealing algorithm under a random procedure to explore the optimal operating parameters and the distillation sequence structure. The shaft work targeting method is used to evaluate the minimum energy cost of the corresponding separation system during the optimization without any need for a detailed design for the heat exchanger network(HEN) and the refrigeration system(RS). The method presented in the paper can dramatically reduce the scale and complexity of the problem. A case study of ethylene cold-end separation is used to illustrate the application of the approach. Compared with the original industrial scheme, the result is encouraging. 展开更多
关键词 Energy System engineering Low-temperature distillation system Process synthesis Distillation sequence Shaft work target
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Development and Application of Heat-integrated Aromatics Fractionation Process
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作者 Yang Weisheng Kong Dejin Tan Yongzhong 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2009年第2期21-26,共6页
The PRO/Ⅱ process simulation software was applied to carry out simulated calculation of the aromatics fractionation unit and the heat integrated rectification process was proposed for the aromatics fractionation sect... The PRO/Ⅱ process simulation software was applied to carry out simulated calculation of the aromatics fractionation unit and the heat integrated rectification process was proposed for the aromatics fractionation section of the 1.0 Mt/a toluene disproportionation unit at the Zhenhai Refining and Chemical Company. The optimized operating parameters were obtained through the energy utilization analysis,process simulation,heat exchanger calculations and comparisons of utility consumption. The operation of commercialized unit has revealed that the design parameters of each rectification column were consistent with the operation results,and the utility consumption was about 47% lower than the traditional heat integrated process. 展开更多
关键词 aromatics fractionation heat integration energy conservation
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A statistical end-to-end performance model for networks with complex topologies
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作者 Chen Yanping Wang Huiqiang Gao Yulong 《High Technology Letters》 EI CAS 2012年第3期308-313,共6页
Network calculus provides new tools for performance analysis of networks, but analyzing networks with complex topologies is a challenging research issue using statistical network calculus. A service model is proposed ... Network calculus provides new tools for performance analysis of networks, but analyzing networks with complex topologies is a challenging research issue using statistical network calculus. A service model is proposed to characterize a service process of network with complex topologies. To obtain closed-form expression of statistical end-to-end performance bounds for a wide range of traffic source models, the traffic model and service model are expanded according to error function. Based on the proposed models, the explicit end-to-end delay bound of Fractional Brownian Motion(FBM) traffic is derived, the factors that affect the delay bound are analyzed, and a comparison between theoretical and simulation results is performed. The results illustrate that the proposed models not only fit the network behaviors well, but also facilitate the network performance analysis. 展开更多
关键词 statistical network calculus arrival curve service curve end-to-end delay bound
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A 3V 5.88mW 13b 400kHz Sigma-Delta Modulator with 84dB Dynamic Range
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作者 李卓 杨华中 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第11期2232-2237,共6页
This paper introduces a high-revolution,200kHz signal bandwidth EA modulator for low-IF GSM receivers that adopts a 2-1 cascaded single-bit structure to achieve high linearity and stability. Our design is realized in ... This paper introduces a high-revolution,200kHz signal bandwidth EA modulator for low-IF GSM receivers that adopts a 2-1 cascaded single-bit structure to achieve high linearity and stability. Our design is realized in a standard 0.18μm CMOS process with art active area of 0.5mm× 1.1mm.The EA modulator is driven by a single 19.2MHz clock signal and dissipates 5.88mW from 3V power supply. The experimental results show that,with an oversampling ratio of 48, the modulator achieves a 84.4dB dynamic range,73.8dB peak SNDR, and 80dB peak SNR in the signal bandwidth of 200kHz. 展开更多
关键词 cascaded sigma-delta modulator analog-digital converter switched-capacitor circuits operational amplifiers CMOS analog integrated circuits
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Dirac multimode ket-bra operators' Q-ordered and P-ordered integration theory and general squeezing operator 被引量:1
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作者 FAN HongYi LOU SenYue 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2013年第11期2042-2046,共5页
We develop quantum mechanical Dirac ket-bra operator’s integration theory in Q-ordering or P-ordering to multimode case,where Q-ordering means all Qs are to the left of all Ps and P-ordering means all Ps are to the l... We develop quantum mechanical Dirac ket-bra operator’s integration theory in Q-ordering or P-ordering to multimode case,where Q-ordering means all Qs are to the left of all Ps and P-ordering means all Ps are to the left of all Qs.As their applications,we derive Q-ordered and P-ordered expansion formulas of multimode exponential operator e iPlΛlkQk.Application of the new formula in finding new general squeezing operators is demonstrated.The general exponential operator for coordinate representation transformation q1q2→A B C D q1q2is also derived.In this way,much more correpondence relations between classical coordinate transformations and their quantum mechanical images can be revealed. 展开更多
关键词 integration theory in Q-ordering or P-ordering Q-ordered and P-ordered expansion formulas multimode exponential operator
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