基于CPLD的光电编码器角位移拟合测速法

针对常用的M法和T法无法满足增量式光电编码器整个测速范围内误差要求的问题,提出了对码盘信号进行角位移拟合求采样时刻即时速度的新方法,在匀加速条件下对这3种方法进行了仿真实验,比较了测速误差。实验结果表明,角位移拟合法在整个速度范围内都能获得很高的测速精度和误差一致性。最后用CPLD对该方法加以实现,给出了Verilog硬件描述语言的设计程序和3种方法的实验结果比较。基于CPLD的实现方法电路简单,运行稳定可靠,处理速度快,为角位移拟合法提供了一种非常好的实现方法。     

锅炉主燃料跳闸保护的设计与分析

锅炉是火力发电的主要设备之一,锅炉MFT（Main Fuel Trip）是锅炉主要设备发生故障时重要的保护手段,也是电厂热工保护的重要内容”,。结合包铝热电厂330MW亚临界机组锅炉设备的特点及实际调试过程,本文分别从锅炉MFT系统的总体结构、控制软逻辑的设计、后备硬跳闸回路的设计等方面对锅炉MFT系统进行详细的介绍,进一步对其安全性和可靠性进行分析,为同类型的锅炉主燃料跳闸系统提供参考。     

Incremental inconsistency detection with low memory overhead

Ensuring models’ consistency is a key concern when using a model‐based development approach. Therefore, model inconsistency detection has received significant attention over the last years. To be useful, inconsistency detection has to be sound, efficient, and scalable. Incremental detection is one way to achieve efficiency in the presence of large models. In most of the existing approaches, incrementalization is carried out at the expense of the memory consumption that becomes proportional to the model size and the number of consistency rules. In this paper, we propose a new incremental inconsistency detection approach that only consumes a small and model size‐independent amount of memory. It will therefore scale better to projects using large models and many consistency rules. Copyright © 2012 John Wiley & Sons, Ltd.     

Branching-time logics with path relativisation

We define extensions of the full branching-time temporal logic CTL^? in which the path quantifiers are relativised by formal languages of infinite words, and consider its natural fragments obtained by extending the logics CTL and CTL⁺ in the same way. This yields a small and two-dimensional hierarchy of temporal logics parametrised by the class of languages used for the path restriction on one hand, and the use of temporal operators on the other. We motivate the study of such logics through two application scenarios: in abstraction and refinement they offer more precise means for the exclusion of spurious traces; and they may be useful in software synthesis where decidable logics without the finite model property are required. We study the relative expressive power of these logics as well as the complexities of their satisfiability and model-checking problems.     

Belief revision within fragments of propositional logic

Belief revision has been extensively studied in the framework of propositional logic, but just recently revision within fragments of propositional logic has gained attention. Hereby it is not only the belief set and the revision formula which are given within a certain language fragment, but also the result of the revision has to be located in the same fragment. So far, research in this direction has been mainly devoted to the Horn fragment of classical logic. Here we present a general approach to define new revision operators derived from known operators, such that the result of the revision remains in the fragment under consideration. Our approach is not limited to the Horn case but applicable to any fragment of propositional logic where the models of the formulas are closed under a Boolean function. Thus we are able to uniformly treat cases as dual Horn, Krom and affine formulas, as well.     

An order-picking operations system for managing the batching activities in a warehouse

Nowadays, customer orders with high product variety in small quantities are often received and requested for timely delivery. However, the order-picking process is a labour-intensive and costly activity to handle those small orders separately. In such cases, small orders are often grouped into batches so that two or more orders can be served at once to increase the picking efficiency and thus reduce the travel distance. In this paper, an order-picking operations system (OPOS) is proposed to assist the formulation of an order-picking plan and batch-handling sequence. The study integrates a mathematical model and fuzzy logic technique to divide the receiving orders into batches and prioritise the batch-handling sequence for picking, respectively. Through the proposed system, the order-picking process can be managed as batches with common picking locations to minimise the travel distance, and the batch-picking sequence can be determined as well. To demonstrate the use of the system, a case study in a third-party logistics warehouse is presented, and the result shows that both the order-picking activity and labour utilisation can be better organised.     

基于EDA技术的数字系统设计

EDA是现代电子数字系统设计的核心技术,其基于电子芯片设计自动化特征,可实现电路数字逻辑系统设计,简化电路硬件设计的结构,提高数字系统可靠性和灵活性。对EDA技术的特征进行分析,介绍EDA设计工具及技术要点,以基于EDA技术的数字系统实例分析为基础介绍EDA技术在数字系统设计中的具体应用,证明EDA技术在电子设计和数字逻辑系统设计中的实用性。     

公式分层的谓词模态逻辑

由于必然模态词□的引入,谓词模态逻辑的公式在一个可能世界中的真假值可能依赖于其可达的可能世界.在谓词模态逻辑中存在个体跨可能世界相等问题.针对这一问题,Lewis提出了对应物理论,并且在对应物理论中用对应物关系来表示个体跨可能世界相等.但是,当一个对象具有一个以上的对应物时,谓词模态逻辑中的跨可能世界相等关系无法与对应物关系建立一一对应.通过限制谓词模态逻辑中全称量词∀的范围,给出了一种公式分层的谓词模态逻辑.它是谓词模态逻辑的一个子逻辑,并且其语言与谓词模态逻辑的语言是相同的.但其公式是分层定义的,使得∀可以出现在□的范围内,并且□不能出现在∀的范围内.由于任意形如∀x□φ（x）的表达式都不是该逻辑的公式,以量词开头的公式在一个可能世界w中的真假值只依赖于w,该逻辑避免了个体跨可能世界相等问题.给出了该逻辑的语言、语法和语义,并证明了该逻辑是可靠的和完备的.     

基于证据理论的陶瓷智能感观评估

陶瓷感官评估结果的表达形式包括语言词汇、象征性符号和数值描述等，它们具有不确定性和不精确性。本文首先运用模糊逻辑技术对这些评估结果定量化，并基于证据理论提出了一种陶瓷智能感观数据融化方法，得到了基于感观数据的质量分级，并取得了较好的实验结果。