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31.
32.
本文在分析手机银行应用现状及手机支付发展趋势的基础上,论证了研发贴近生活的缴费支付功能的必要性和迫切性,并结合现有成熟的信息技术,提出了应用于手机银行的缴费模式和支付模式,从功能创新出发来拓宽手机银行的应用面,提高手机银行的竞争力。 相似文献
33.
数据加密是保护数据安全的一种有效的方法,它是将一段明文按某种算法进行处理,使其成为密文,以保护数据不被非法人窃取、阅读。数据加密技术常分为"对称式"加密与"非对称式"加密两类。多步加密算法属对称式加密,由于安全性高得到广泛应用。 相似文献
34.
Chih-chiang Yang 《Quality and Quantity》2007,41(6):831-849
The paper proposes a general framework for modeling multiple categorical latent variables (MCLV). The MCLV models extend latent
class analysis or latent transition analysis to allow flexible measurement and structural components between endogenous categorical
latent variables and exogenous covariates. Therefore, modeling frameworks in conventional structural equation models, for
example, CFA and MIMIC models are feasible in the MCLV circumstances. Parameter estimations for the MCLV models are performed
by using generalized expectation–maximization (E–M) algorithm. In addition, the adjusted Bayesian information criterion provides
help for model selections. A substantive study of reading development is analyzed to illustrate the feasibility of MCLV models. 相似文献
35.
随着我国科学技术的不断发展,计算机被广泛应用于各行各业的发展建设以及人们日常生活和学习中,在给人们带来较大便利的同时,也存在安全隐患。网络安全问题威胁到了计算机信息的保密性,给计算机的可持续发展带来了安全隐患,若用户的信息被泄露会给用户带来巨大的财产损失及心理伤害。因此,出现了数据加密技术,其为计算机网络安全提供了很好的保障。基于此,论文对数据加密技术在提高网络安全性中的应用方面作了简要阐述。 相似文献
36.
文章针对通信基站机房节能降耗的需求,设计并实现了一种联网型的智能通风节能控制系统。系统采集机房内外环境温、湿度实时监测数据,采用智能逻辑算法,控制进风机、出风机和机房空调设备的运行,充分利用机房室内外的温差,依靠大量的空气流通实现室内散热,以达到节能降耗的目的。联网型的设计保证了系统灵活的组网方式,更适合全程控制和集中维护。通过一年多的运行证明,系统能够在保证通信机房设备运行工作环境的同时,大幅降低机房空调的耗电,使设备维护方便、运行稳定,达到了设计目的。 相似文献
37.
RSA算法在文件加解密应用中具有非常广泛的应用前景,本文就RSA算法进行了较为深入地研究,并对其作为当前最为实用的加解密方法为文件的加解密提出了自己的认识。 相似文献
38.
We present an economically motivated two–factor term structure model that generalizes existing stochastic mean term structure models. By allowing a certain parameter to acquire dynamical behavior we extend the two–factor model to obtain a nonlinear three–factor model that is shown, in a deterministic version, to be equivalent to the Lorenz system of differential equations. With reasonable parameter values the model exhibits chaotic behavior. It successfully emulates certain properties of interest rates including cyclical behavior on a business cycle time scale. Estimation and pricing issues are discussed. Standard PCA techniques used to estimate HJM type models are observed to be equivalent to dimensional estimates commonly applied to 'spatial data' in nonlinear systems analysis.
It is concluded that techniques commonly used in the analysis of nonlinear systems may be directly applicable to interest rate models, offering new insights in the development of these models. Tests of nonlinearity in interest rate behavior may need to focus on long cycle times. 相似文献
It is concluded that techniques commonly used in the analysis of nonlinear systems may be directly applicable to interest rate models, offering new insights in the development of these models. Tests of nonlinearity in interest rate behavior may need to focus on long cycle times. 相似文献
39.
Due to the complex mapping relationship between product attributes and engineering characteristics, as well as the correlations between engineering characteristics and the engineering constraints on a product, a new product following a probabilistic rule of multidimensional scaling may not be in an optimal position in product engineering space. In this paper, a new methodology for optimal product positioning by considering engineering constraints is proposed. In the proposed methodology, perceptual mapping and house of quality are introduced to link the consumer perceptual space, and product engineering space. The degree of overall customer satisfaction is considered in the rule of consumer choice probability. Based on this, an optimal product positioning model can be established. Genetic algorithms are introduced to solve the problem of the optimization model due to its non-linear characteristics. By applying genetic algorithms, the optimal value settings of a new product's engineering characteristics can be obtained. An example of optimal positioning and determination of value settings of engineering characteristics of packing machines is used to illustrate the proposed methodology. 相似文献
40.
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