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51.
Zhe-Ming Lu Author Vitae Jun-Xiang Wang Author Vitae Bei-Bei Liu Author Vitae 《Journal of Systems and Software》2009,82(6):1016-1024
Copyright protection and information security have become serious problems due to the ever growing amount of digital data over the Internet. Reversible data hiding is a special type of data hiding technique that guarantees not only the secret data but also the cover media can be reconstructed without any distortion. Traditional schemes are based on spatial, discrete cosine transformation (DCT) and discrete wavelet transformation (DWT) domains. Recently, some vector quantization (VQ) based reversible data hiding schemes have been proposed. This paper proposes an improved reversible data hiding scheme based on VQ-index residual value coding. Experimental results show that our scheme outperforms two recently proposed schemes, namely side-match vector quantization (SMVQ)-based data hiding and modified fast correlation vector quantization (MFCVQ)-based data hiding. 相似文献
52.
Flash memory efficient LTL model checking 总被引:1,自引:0,他引:1
S. EdelkampD. Sulewski J. BarnatL. Brim P. Šime?ek 《Science of Computer Programming》2011,76(2):136-157
As the capacity and speed of flash memories in form of solid state disks grow, they are becoming a practical alternative for standard magnetic drives. Currently, most solid-state disks are based on NAND technology and much faster than magnetic disks in random reads, while in random writes they are generally not.So far, large-scale LTL model checking algorithms have been designed to employ external memory optimized for magnetic disks. We propose algorithms optimized for flash memory access. In contrast to approaches relying on the delayed detection of duplicate states, in this work, we design and exploit appropriate hash functions to re-invent immediate duplicate detection.For flash memory efficient on-the-fly LTL model checking, which aims at finding any counter-example to the specified LTL property, we study hash functions adapted to the two-level hierarchy of RAM and flash memory. For flash memory efficient off-line LTL model checking, which aims at generating a minimal counterexample and scans the entire state space at least once, we analyze the effect of outsourcing a memory-based perfect hash function from RAM to flash memory.Since the characteristics of flash memories are different to magnetic hard disks, the existing I/O complexity model is no longer sufficient. Therefore, we provide an extended model for the computation of the I/O complexity adapted to flash memories that has a better fit to the observed behavior of our algorithms. 相似文献
53.
合成氨工艺参数优化技术开发及应用 总被引:1,自引:1,他引:0
以氨净值为响应值,影响响应值的17个过程参数为变量,经逐步回归选入触媒温度左3,触媒温度左4,循环CH_4%,H/N,NH_3%(进口)5个过程参数建立预测方程,并根据该方程对响应值的拟合结果和误差分布对样本进行分类。在此基础上,采取图形显示技术和统计分析的方法对分类样本集的过程参数进行比对分析,由此获取优类信息制订优化的工艺参数方案,经仿真验证后用于指导合成氨装置的生产试验。试验结果与试验前的对照期比较,氨净值均值由13.86提高到14.54,吨氨气耗减少15.9887m~3,吨氨电耗减少15.8kWh,节能效益十分明显 相似文献
54.
Re-engineering of the design process for concurrent engineering 总被引:20,自引:0,他引:20
Dunbing Tang Li Zheng Zhizhong Li Dongbo Li Shiqi Zhang 《Computers & Industrial Engineering》2000,38(4):479-491
According to the requirements of concurrent engineering, three interdependency relationships (uncoupled relationship, coupled relationship and decoupled relationship) between design activities are presented in this paper. And the coupled relationship plays an important role in concurrent product design process. To represent the precedence relationships among design activities, a directed graph is used to describe the design process. And the interdependency relationship between activities is illustrated by a Design Structure Matrix which is the transpose of the accessibility matrix of the corresponding graph. Using the DSM, an algorithm of recognizing the coupled activities during the design process is presented. Moreover, an algorithm to figure out the order levels of activities during the design process is proposed. And both algorithms are illustrated with a die design example. 相似文献
55.
采用 Win95操作系统 ,以 VB为开发工具 ,对运城地区农业工程信息进行快速检索并长期存储。该系统成本低、实用性强 ,人机交换界面使用方便 ,不需专业培训 ,为大型农业建设工程信息资料的检索和存储开辟了一条新的途径 相似文献
56.
GU Lei 《数字社区&智能家居》2008,(25)
劝导技术是利用计算机、设备及应用软件来影响人类想法及行为的技术。该文对劝导技术的发展及其现状进行了综述,并着重对劝导技术的可信度及其三类劝导技术应用结果通过心理学的角度进行了分析。系统生命周期是现代设计方法理念的一个重要概念,该文介绍了系统生命周期,并介绍了基于系统生命周期中的劝导技术的设计评估行为。该文为劝导技术产品研究设计分析提供了系统的理论的指导。 相似文献
57.
JIN Xu-wei 《数字社区&智能家居》2008,(16)
对学校图书馆的业务进行分析研究,从软件工程的角度,设计出学校图书馆管理系统的总体结构,并且对系统中的主要功能模块的实现方法进行了详细的描述。该系统的建设实现了图书馆管理和服务的自动化,具有实际应用价值。 相似文献
58.
In this paper, the general problem of Euclidean combinatorial optimization under uncertainty is formulated for the first time
and the concepts of a stochastic multiset, a multiset of fuzzy numbers, a stochastic Euclidean combinatorial set, and general
Euclidean combinatorial set of fuzzy stochastic numbers that combines the properties of both types of uncertainty are introduced.
__________
Translated from Kibernetika i Sistemnyi Analiz, No. 5, pp. 35–44, September–October 2008. 相似文献
59.
This paper contextualises, describes and discusses a student project which takes a particular exploratory approach to using
mathematical surface definition as a language and vehicle for co-rational design co-authorship for architecture and engineering.
The project has two authors, one from an architectural and one from an engineering educational background. It investigates
the metaphorical and operational role of mathematics in the design process and outcomes. 相似文献
60.