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101.
毛建儿 《浙江工商职业技术学院学报》2010,9(2):36-38
随着通信的飞速发展,信息安全显得越来越重要,计算机密码体制的基本思想就是将要保护的信息变成伪装信息,在公开密钥算法提出之前,所有密码系统的解密密钥和加密密钥彼此有着直接的联系,这也是秘密密钥的缺陷所在。为此公开密钥算法RSA算法就顺应而生。这种叫加密算法可用VB程序编程实现。 相似文献
102.
Junliang He Daofang Chang Weijian Mi Wei Yan 《Transportation Research Part E: Logistics and Transportation Review》2010,46(1):136-155
This paper aims at postulating a novel strategy in terms of yard crane scheduling. In this study, a dynamic scheduling model using objective programming for yard cranes is initially developed based on rolling-horizon approach. To resolve the NP-complete problem regarding the yard crane scheduling, a hybrid algorithm, which employs heuristic rules and parallel genetic algorithm (PGA), is then employed. Then a simulation model is developed for evaluating this approach. Finally, numerical experiments on a specific container terminal yard are used for system illustration. Computational results suggest that the proposed method is able to solve the problem efficiently. 相似文献
103.
黄汉南 《广东农工商职业技术学院学报》2001,17(3):71-76
本提出了一种用于无损灰度图象数据压缩新的编码方法-一种基于对LZ77压缩方法的改进以及对图象元素预测误差的估计为基础的字典压缩方法,并给出了该方法的C语言程序实现。 相似文献
104.
多载波通信系统中,发射机因为功率器件的非线性特性,会产生
多阶交调,影响发射信号频谱质量。介绍了一种大功率多载波发射机的新设计,该设计采用
运用快速初相搜索算法优化的信号产生、带AGC的上变频器和平衡式功率放大器。理论和实
践证明,该设计兼顾信号的线性度和整机效率,对交调分量、谐杂波等有较好抑制,能获得
较好的信号频谱和较高的效率。 相似文献
105.
This paper proposes a model to better capture persistent regime changes in the interest rates of the US term structure. While the previous literature on this matter proposes that regime changes in the term structure are due to persistent changes in the conditional mean and volatility of interest rates we find that changes in a single parameter that determines the factor loadings of the model better captures regime changes. We show that this model gives superior in-sample forecasting performance as compared to a baseline model and a volatility-switching model. In general, we find compelling evidence that the extracted factors from our term structure models are closely related with various economic variables. Furthermore, we investigate and find evidence that the effects of macroeconomic phenomena such as monetary policy, inflation expectations, and real economic activity differ according to the particular regime realized for the term structure. In particular, we identify the periods where monetary policy appears to have a greater effect on the yield curve, and the periods where inflation expectations seem to have a greater effect in yield determination. We also find convincing evidence of a relationship between the regimes estimated by the various switching models with economic activity and monetary policy. 相似文献
106.
107.
Assessment of the effect of the financial crisis on agents’ expectations through symbolic regression
Agents’ perceptions on the state of the economy can be affected during economic crises. Tendency surveys are the main source of agents’ expectations. The main objective of this study is to assess the impact of the 2008 financial crisis on agents’ expectations. With this aim, we evaluate the capacity of survey-based expectations to anticipate economic growth in the United States, Japan, Germany and the United Kingdom. We propose a symbolic regression (SR) via genetic programming approach to derive mathematical functional forms that link survey-based expectations to GDP growth. By combining the main SR-generated indicators, we generate estimates of the evolution of GDP. Finally, we analyse the effect of the crisis on the formation of expectations, and we find an improvement in the capacity of agents’ expectations to anticipate economic growth after the crisis in all countries except Germany. 相似文献
108.
109.
在C-RAN(Centralized,Cooperative,Cloud RAN)无线网络架构中,协作多点传输受到符号定时偏差和载波频率偏差的影响。为了降低联合传输协作系统对异步信号的敏感性,将正交预编码的同步算法应用到联合传输协作系统中。首先,发射机发送经过重复编码和正交预编码矩阵处理后的数据信息;然后,接收机利用特定的接收矩阵,实现分离相互叠加的异步协作信号;最后,完成对协作信号载波频率偏差和符号定时偏差的估计和补偿。理论分析和仿真结果表明:该方法能够有效解决协作传输中信号异步问题,改善系统性能。 相似文献
110.