脉冲行波管阴极蒸发现象的验证与解决

针对某型脉冲行波管工作中出现失效的问题,通过试验分析确定失效是由阴极蒸发所致,在对阴极进行试验研究的基础上,找出了阴极的蒸发规律,通过采取改进阴极预处理工艺和适当降低阴极温度等措施,解决了阴极改盐后产生的蒸发问题;而增加行波管测试老炼时间,则提高了行波管工作稳定性和质量一致性。     

LTV model in consultant sector. Case study: mental health clinic

Since the early 1980s, customer relationship management (CRM) has been important in the new competitive business environment. Today, due to development of competitive factors in the business, the enterprise's need to create and retain effective relations with customers has been highlighted more and more. With the aim of customer scoring applications, the most profitable customers can be identified. In this paper, we categorized customers by three types of values for the clinic by using logistic regression as a data-mining technique, and calculated the customer defection and future purchase probability in a mental health clinic of the university of Tehran. Model verification and validation (using lift chart) was done and customer segmentation and analysis presented with proper marketing strategies.     

Process modeling and analysis of manufacturing supply chain networks using object-oriented Petri nets

This paper presents a systematic methodology for modeling and analysis of manufacturing supply chain business processes. The proposed approach first employs Computer Integrated Manufacturing Open System Architecture (CIMOSA) behavior rules to model the business process routing structures of manufacturing supply chain networks. Object-oriented predicate/transition nets (OPTNs) are then developed for the modular modeling and analysis of process models. Based on the structure of OPTNs, a procedure to obtain the system's P-invariants through objects’ P-invariants is suggested. From the P-invariants obtained, system structural properties such as deadlock and overflow can be analyzed. By using Petri net unfolding techniques and by extracting the process model of each object from the entire process model, the sequencing analysis for operations in supply chain processes becomes possible. Several manufacturing supply chain examples are used to illustrate the effectiveness of the proposed method.     

A dynamic specification to automatically debug and correct various divider circuits

This paper presents a formal technique to verify and debug division circuits on fixed point numbers. The proposed technique is based on a reverse-engineering mechanism of obtaining a high level model of the gate level implementation and also introducing an intermediate representation of the specification that makes equivalence checking between two models possible. The main advantage of this representation is the fact that the specification is dynamically updated according to the information obtained from the implementation. At the end, if two updated models are not equivalent, possible bugs can be localized and then corrected automatically by analyzing the difference, if possible. Experimental results show the robustness of the proposed technique in comparison with other contemporary methods in terms of the run time and also show that two orders of magnitude average speedup is obtained.     

钢筋混凝土框架结构施工技术

对多层框架结构施工过程中遇到的技术问题及解决方案进行论述,对做好类似工程的施工技术工作具有借鉴意义。     

Abstract Interaction Objects

The concept of an ‘interactor’ has been introduced by Faconti and Paterno' [6] as an abstraction of an entity in interactive graphics capable of both input and output. However the notion of interaction object need not be confined to graphics systems; it represents a useful structure for thinking and reasoning about the behaviour of interactive systems in general. As part of Esprit Basic Research Action 7040 (Amodeus-2) we are using the concept of interactor, and existing work on state-based processes and agents, to develop a model and theory of interactive systems. In this paper we describe two formal models for interaction objects and sketch how they can be used to build a small vocabulary of operators to support the rigorous specification of a graphics system. Our model differs from the approach of Faconti and Paterno' in that it abstracts away from any specific graphics framework and is thus suited to the level of abstraction demanded by formal approaches to system development.     

日本新建筑标准的结构抗火设计

本的目的是为了说明1998—2000期间日本建筑规程(日本建筑标准)以及相关技术标准的修订。考虑了功能要求后，规程修订趋向于以性能为主。在抗大这一章节中，功能要求指的是在发生火灾时防止结构倒塌以及火势向其他隔问的蔓延，同时还包括防止火势由失火建筑物内部向周围建筑的扩散。为了满足功能上的要求，我们提供了三种方法(A、B、C)。方法A是传统的设计方法，即建筑框架及隔墙采用防火构件。相对于方法A，新近引进了以考虑性能为主的方法B。在方法B中，由一系列设计公式计算出指定部分发生火灾可能产生的后果、结构和边界部分的热反应、构件破坏的临界时间。设计公式应足够简单，以便于建筑工程师和有关官员的使用。由方法B计算出的结果通常是保守的。方法C是一个框架，用最先进的设计方法。规程没有指定采用的设计方法，但是工程上火灾和结构分析的结果只有在全面地考证后才能被行业接受。     

Verifying local stratifiability of logic programs and databases

In this paper, we deal with the problem of verifying local stratifiability of logic programs and databases presented by Przymusinski. The notion of dependency graphs is generalized from representing the priority relation between predicate symbols to representing the priority between atoms. Necessary and sufficient conditions for the local stratifiability of logic programs are presented and algorithms for performing the verification are developed. Finally, we prove that a database DB containing clauses with disjunctive consequents can easily be converted into a logic program P such that DB is locally stratified iff P is locally stratified. Yi-Dong Shen, Dr.: Department of Computer Science, Chongqing University, Chongqing, 630044, P.R. China (Present Address) c/o Ping Ran, Department of Heat Power Engineering, Chongqing UniversityResearch interests: Artificial Intelligence, Deductive Databases, Logic Programming, Non-Monotonic Reasoning, Parallel Processing     

Critique of the Lake Arrowhead Three

The photograph and autobiography of Dr. Leslie Lamport were published in Volume 4, Issue No. 2, 1990 on page 59     

Quantified Computation Tree Logic

Computation Tree Logic (CTL) is one of the most syntactically elegant and computationally attractive temporal logics for branching time model checking. In this paper, we observe that while CTL can be verified in time polynomial in the size of the state space times the length of the formula, there is a large set of reachability properties which cannot be expressed in CTL, but can still be verified in polynomial time. We present a powerful extension of CTL with first-order quantification over sets of reachable states. The extended logic, QCTL, preserves the syntactic elegance of CTL while enhancing its expressive power significantly. We show that QCTL model checking is PSPACE-complete in general, but has a rich fragment (containing CTL) which can be checked in polynomial time. We show that this fragment is significantly more expressive than CTL while preserving the syntactic beauty of CTL.