Comparison between cellular automata and linear feedback shift registers based pseudo-random number generators

A detailed comparison between pseudo-random number generators (PRNGs) based on cellular automata (CA) and linear feedback shift registers (LFSRs) is presented in this paper. Various statistical tests have been applied in order to reveal the advantages and disadvantages of both approaches. Both LFSRs and hybrid additive cellular automata (HACA) produce satisfactory PRNGs. HACA operate at higher speeds than LFSRs with the same characteristic polynomials. Regarding the silicon area, direct comparisons between the two approaches cannot be made since it depends on the PRNG length. However, the inherent modularity of HACA reduces the silicon area occupied by them and, when long feedback paths are used, the silicon area occupied by LFSRs increases.     

滴流床设计放大中的重要参数及其数学模型

讨论了在滴流床放大过程中必须加以考虑的重要物理和化学因素以及这些因素对设计放大的影响．介绍了确定这些参数的原理和方法，推荐了用于计算这些参数的关系式，列举了用于不同反应系统的数学模型，比较了模型预测值与实验值．     

不规则形状拉深件毛料的计算机辅助设计

采用不同高度上的截面形状对复杂形状斜壁拉深件的外形进行描述。应用势流原理和边界元法对拉深件进行逐层展开。这种方法兼有理论上的可靠性和计算方法上的简单实用性，并且对复杂形状的直壁、斜壁拉深件皆适用。通过验算，用本文方法所得毛料外形合理，具有实用价值     

钢筋混凝土悬臂深梁正截面承载力计算

通过结构试验和非线性有限元分析，研究了钢筋混凝土悬臂深梁在集中荷载作用下的受力性能，并给出了正截面承载力计算公式．     

OOPA──面向对象支持的原型化开发方法

从基本概念，图形工具和开发模型三个方面介绍了一种计算机软件开发方法——面向对象支持的原型化开发方法ＯＯＰＡ（Ｏｂｊｅｃｔ－ＯｒｉｅｎｔｅｄＰｒｏｔｏｔｙｐｉｎｇＡｐｐｒｏａｃｈ），试图提供面向对象与原型法相结合进行软件开发的具体的方法论．     

网络管理信息系统安全对策探索

网络管理信息系统的应用越来越广泛，这时网络管理信息的安全提出了更高的要求，本文针对网络管理信息系统的特点，提出了一个网络管理信息系统的安全结构模型，分析了相应的安全对策。     

Monitoring of multivariable dynamic processes and sensor auditing

Industrial continuous processes are usually operated under closed-loop control, yielding process measurements that are autocorrelated, cross correlated, and collinear. A statistical process monitoring (SPM) method based on state variables is introduced to monitor such processes. The statistical model that describes the in-control variability is based on a canonical variate (CV) state space model. The CV state variables are linear combinations of the past process measurements which explain the variability of the future measurements the most, and they are regarded as the principal dynamic dimensions. A T² statistic based on the CV state variables is utilized for developing the SPM procedure. The CV state variables are also used for monitoring sensor reliability. An experimental application to a high temperature short time (HTST) pasteurization process illustrates the proposed methodology.     

Computerized relational model for powder technology: powder and process selection

Part of a complete expert-system software design for powder technology is presented. This part of the system deals with powder selection according to predetermined, recommended or required material properties, and specific powder characteristics. Then the optimum powder production, i.e processing, method is determined, which satisfies the requirements of the specified powder. For this purpose a detailed database relational model is developed, and the system's software modules are described. A relational model is formulated and a structured query language (SQL) is used in the detailed software design presented.     

Migration Processes II: The Discrete Case

Following the study of migration processes in the continuous domain in Part I of this paper, we reformulate the concept of migration in the discrete domain (Z^m) and define Discrete Migration Processes (DMP). We demonstrate that this model is a natural discrete representation of the continuous model and maintains the model's features in a qualitative sense. We show that under discrete migration any discrete set shrinks to a limit in finitely many iterations. The discrete representation provides an advantageous basis for digitally implementing the MP model. Using this implementation we illustrate the discrete migration of various types of sets under various types of constraints.     

Typology of database quality factors

Databases are a critical element of virtually all conventional and ebusiness applications. How does an organization know if the information derived from the database is any good? To ensure a quality database application, should the emphasis during model development be on the application of quality assurance metrics (designing it right)? A large number of database applications fail or are unusable. A quality process does not necessarily lead to a usable database product. A database application can also be ‘well-formed’ with high data quality but lack semantic or cognitive fidelity (the right design). This paper expands on the growing body of literature in the area of data quality by proposing additions to a hierarchy of database quality dimensions that includes model and behavioral factors in addition to process and data factors.