Pulse analysis of patients with severe liver problems. Studyingpulse spectrums to determine the effects on other organs

Blood tests and ultrasound scanning are the standard techniques for the diagnosis of liver problems. However, there is no easy assessment of how liver problems affect other parts of the body, such as the spleen, stomach, lung, and gallbladder. Traditional Chinese medicine makes use of pulse analysis to diagnose such conditions. Here, the authors study the pulse spectrum of patients with liver problems, with the goal of using this technique to analyze related conditions     

Power company fuel supply — Problems and solutions

A power company in the business of supplying electricity to its customers faces numerous problems associated with power production. One of its major problems is to supply its power plants with fuel and to use that fuel as economically as possible.The purpose of this paper is to discuss the difficulties that a power company has in supplying itself with fuel and to propose a technique that will produce a more prudent and economical use of fuel. The technique utilizes a multistage computer algorithm, which takes into consideration the power company's complete fuel supply process from coal mine to busbar. It requires a mathematical modeling of this process and allows for as much modeling flexibility as possible.     

基于级联逆变器的光伏发电系统的新控制方法

针对传统光伏并网系统结构存在的问题,提出了一种新的阶梯波与电流瞬时值反馈混合控制的光伏并网级联逆变器方案.该方案对一部分级联单元采取梯形波控制,一部分级联单元采取带电流瞬时值反馈的倍频移相SPWM控制,两部分串联叠加形成输出电压,并对逆变器输出电压进行了谐波分析.针对阶梯波调制逆变器的触发角提出了一种简易算法,该算法适...     

火电厂二氧化硫排污收费的问题及建议

依据我国二氧化硫排污收费的法规政策,分析9个方面的基本问题;总结分析电力系统实际收取及使用二氧化硫排污收费情况;结合电力体制改革的状况,提出积极反映收费问题,积极争取补助金的使用,分散收取、集中返还电力集团公司,减化手续,加强监督,出台优惠政策等建议。     

电力系统静态等值改进算法的研究

随着电网互联网络的不断增大,电力系统等值方法研究有着越来越重要的意义。但是,在传统的电力系统W ard静态等值方法中存在一些不适合工程应用的问题。这些问题主要包括如何求取接地支路参数和边界节点功率注入。针对这些问题,文章根据实际研究情况,改进了传统的静态等值方法,尤其改进了接地支路参数与边界节点注入功率的求解过程,使其能够适用于工程应用,并通过山东585电网系统验证改进后静态等值算法的正确性。     

Unified matrix presentation of Maxwell's and wave equations usinggeneralized differential matrix operators [EM engineeringeducation]

In this paper, the authors introduce the concept of generalized differential matrix operators (GDMOs) that are useful for the formulation of electromagnetic boundary value problems in arbitrary orthogonal coordinate systems, e.g., Cartesian, cylindrical and spherical. The most significant attribute of the GDMO approach is that their use helps to simplify the complicated manipulation of vector differential equations, especially in problems dealing with an anisotropic media. They show that the use of the GDMOs enable one to replace, for most problems in electromagnetics, the complicated vector differential operations with manipulation of 3×3 matrices. In addition, they demonstrate GDMOs are convenient for deriving many differentiation identities and integral theorems which find extensive applications in electromagnetics     

一种融合时间特征的非侵入式负荷辨识决策方法

针对家庭负荷用电场景中负荷类别的不确定性,以及非侵入式负荷监测设备数据库中负荷特征库的不完备等极易导致负荷辨识准确率下降的问题,文中在利用电气特征的基础上,提出了一种融合负荷运行时长、运行时段、工作周期及假期特性等时间特征的非侵入式负荷辨识决策方法.在该方法中,通过分段归一化的Mean-shift聚类方法对检测得到的负...     

Providing senior design students with a clinical perspective.

This article aims to provide students with a clinical perspective of medical device design. This study shows that it is not only important for students to understand how medical devices are designed and function but how these devices are used by patients, physicians, surgeons, nurses, and physical therapists too. For implantable devices, this includes problems associated with the preparation, insertion, and removal of devices in a patient's body. For monitoring or imaging equipment, this includes problems associated with device set up and operation and interpretation of data. This knowledge is important to medical device designers who may be able to avoid or solve many of these problems through good design.     

A survey of current operational problems [of power systems]

This paper is one of a series prepared for use in the Working Group on Current Operational Problems (COPS) forums with the goal of focusing attention of the industry on problems faced by those who are involved in actual power system operation. The results of a survey on operational problems are presented. Statistical information compiled for various categories of operational problems is given with some general observations about the results. A rough comparison is made between the results of this survey and the first COPS problem list of 1976     

Framing Questions to Attain Higher Educational Objectives (Educator's Corner)

The principal purpose of this article is to help engineering teachers improve the exercises and problems they use in classroom activities, homework assignments, and tests, and which are the dominant learning vehicles in much of engineering education. The intimate relationship between classroom problems and educational objectives is elucidated through the recently revised Bloom's taxonomy of cognitive skills, which organizes the learners' abilities in a hierarchy with six major categories and emphasizes the importance of attaining the higher-level abilities. The selection and construction of problems to reach a wider set of educational objectives is described in detail and illustrated through problems taken from the topic of noise figure of cascaded linear two-port networks to demonstrate how different cognitive abilities can be exercised within the same subject matter.     

Inverse‐free second moment method for electrical systems with uncertain parameters

Engineering systems are usually designed deterministically, but if there are uncertainties in parameters, an appropriate approach is to use probabilistic methods. For reliability estimation it is necessary to have at least the first two moments including means and covariances of the output variables. Most of the existing methods applied to problems involving linear systems need inverses of matrices. There are two problems with these approaches. First, for large sparse linear systems (for example, a tri‐diagonal system) the inverse is fully dense. Second, the mean of the random matrix has to be non‐singular. In this paper, we present a new method to automatically formulate the moment equations that aims to overcome the drawbacks of these methods and apply it on electrical networks. This method does not require an inverse and able to solve problems when the mean matrix of a system is singular. In addition, it takes advantage of both sparsity (zero elements) and deterministic coefficients. This method can be used to solve both uncorrelated and correlated cases. To demonstrate the feasibility of this method, a quantitative comparison with another existing method requiring the inverse and with Monte Carlo results is done. Copyright © 2005 John Wiley & Sons, Ltd.     

Development of an interactive CDROM-based tutorial for teachingMATLAB

This paper describes the development of an interactive computer-based tutorial for MATLAB. This tutorial has been developed for undergraduate or graduate students who have had little or no exposure to MATLAB. Students are guided through new concepts and syntax with useful aids such as audio, video and interactive exercises. The exercises, implemented in a specially designed exercise window, give the students an opportunity to use MATLAB to solve problems immediately after covering new concepts. The exercise window has a background interface to MATLAB and thus all commands entered in the window are executed by MATLAB. Hints, example solutions, multiple choice quizzes and test problems, requiring the use of proper MATLAB structure and syntax, add to the learning experience. This project was initially undertaken to investigate student response to alternate computer-based teaching methods. Thus student input has played an important part in the development of this tutorial. Subjective feedback from students, which is presented in the paper, indicate great promise for this alternate approach to teaching MATLAB     

Engineering Reality in Single-Answer Problems

The purpose of this work has been to investigate one method by which some of the outside reality of the world of engineering can be presented in single-answer problems. The technique involves a tool readily available to all engineering educators: the current technical literature. Single-answer problems are particularly important in the earlier phases of engineering education, when they serve to develop the student's capacity to use fundamental intellectual abilities such as recall and manipulation. Textbook problems are typical. They are generally considered to have little direct relation to the real world of engineering. However, if some of this outside reality can be presented in such problems, the student will perceive them as relevant and will be motivated to higher levels of achievement.     

一种两相流动态数学模型的建模方法及应用

该文介绍了一种实用的两相流集总参数数学模型的建模方法,方法使用Ｚｕｂｅｒ Ｆｉｎｄｌａｙ的漂移通量模型,系统地综合了建立两相流动和传热问题数学模型的能量守恒、质量守恒和动量守恒的动态方程。通过这种方法在核电站蒸发器系统仿真研究中的应用,证实了这种建模方法的可靠性,该方法可适用于工程中常见的两相流动问题。     

2、3号炉自动控制系统在DCS上的逻辑改进

对2、3号炉自动控制系统在DCS改造中遇到的诸多问题进行分析，并提出了解决问题的方法，提高了自动投入率。     

浅谈110kV线路保护与SF6断路器配合时的重合闸问题

110kV电网中大量采用SF6带弹簧机构的开关,为了使线路保护装置与该型开关更好地配合,就配合时重合闸方面存在的问题进行了分析。CSL-160B线路保护装置在与该型开关配合中,特定情况下,永跳后重合闸会误动作,文中从断路器和保护装置两个方面提出了解决方案。     

A showcase of adaptive controller designs

The adaptive control literature contains hundreds of technical papers on many different approaches to the subject. However, engineers who are not specialists in adaptive theory often have difficulty selecting which approach to use in any given problem. This series of papers addresses this situation by defining a set of standard problems which are then solved by several distinct approaches to adaptive control. This introductory paper defines the problems and guidelines which have been used in this process.     

Introducing real world design problems into the undergraduateelectromagnetic curriculum

General-purpose CAD (computer-aided design) programs have been used to teach electromagnetics to undergraduates at Carnegie Mellon University. The focus of the instruction is the use of real-world design problems to teach basic electromagnetics concepts. Students use computers to set up and solve a variety of electrostatics, magnetostatics, eddy current, and microwave problems. This gives them the opportunity to visualize EM fields and to interact with real-world devices and issues. Experience shows that solving such problems by means of electromagnetic CAD tools boosts student motivation and leads to a better grasp of key technical concepts     

Finding the missing link

The manufacture of large fabricated metal structures poses a number of significant problems, particularly when attempts are made to automate the process. This article describes some new techniques that are being developed to solve many of these problems, thereby opening up the possibility of automating the assembly of many products such as aircraft, transportation systems or large pre-fabricated structures. One of these techniques combines simulation based control with non-contact metrology, mathematical modeling and innovative robot end-effectors to provide practical solution and allow the effective and safe use of industrial robots within a partially defined environment. Using this technique, a working demonstrator cell was developed and is being evaluated using fuselage components from the Canadair CRJ700 regional jet. The system has been developed primarily for use in the manufacture of airframes but the technique is applicable to any structures that are liable to deformation during assembly.     

Adaptation problems in expert systems

Expert system (ES) theory problems have been traditionally considered without any essential connection with common control problems. However, nowadays, because of progress in ES theory development in practice and because of its wide use for solving complex control problems, new items in this field of research are being stressed, many of which are connected with traditional automation control. The combined study of adaptation and ES problems makes it possible to draw significant practical conclusions for systems of both types. In this work an analysis of general problems and of possible approaches to solving them in some special types of ESs based on Bayes inference is carried out. The main attention is focused on such ES characteristics as: (i) inference stability (with respect to variations in probabilistic approximation measures of rule truth); (ii) knowledge base adaptation (rule modification and new rule creation or approximation measure rule tranformation); (iii) knowledge base consistency maintenance.