Electro-forensic engineering: an emerging profession

With the increasing number of legal cases involving the application of electrical equipment, forensic engineering is playing a greater role in providing litigation support. This article discusses the qualifications and role of the electro-forensic engineer. Safety practices, importance of codes and standards and how to minimize accidents and liability are growing concerns with electrical equipment manufacturers, systems designers, contractors and owners. The electro-forensic engineer can make positive contributions beyond litigation support as explained in this article. The need for recommended practices or standards for the electro-forensic engineer to perform in a professional manner is also discussed     

A biomedical engineer''s experience in Nicaragua

The experiences of a 12-member team composed of physicians, nurses, a respiratory therapist, a rehabilitation engineer with specialty training in prosthetics and orthotics, and a biomedical engineer at a third-world medical facility are described. The obstacles encountered in the form of limited equipment, the state of disrepair of existing equipment, and environmental factors (heat and humidity) are discussed. The question of how best to help developing countries is examined.     

Three kinds of ethics for three kinds of engineering

The phenomenon of the engineering enterprise stands within a web of contextual relationships, and the elements of (1) the engineer, (2) engineering and (3) the engineered stand out as fundamental to the engineering enterprise. Each element is contextual in the sense of being integrated into a more or less coherent realm of discourse consisting of thoughts, actions, words, things, roles and goals. That realm of discourse indicates the contexts that condition and are conditioned by the engineering enterprise. Corresponding to each of the three elements of the engineering enterprise is an appropriate and distinct type of ethics. (1) Virtue ethics is appropriate to the engineer who engineers the engineered. It asks how the engineer can be good in a moral sense. (2) Conceptual ethics is appropriate to engineering, which aims at the production of the engineered and requires the engagement of engineers. It asks how engineers can do good engineering. (3) Material ethics is appropriate to the engineered, which follows from the engineering process via the efforts of the engineer. It asks how engineering can make products that contribute to the common good in a convivial society. Being, doing and making are all bound up in the statement “The engineer engineers the engineered”. We cannot separate the engineer, engineering and the engineered, either from each other or from the contexts in which they are embedded, but we can distinguish them, and with each we can associate a different kind of ethics     

Engineering licenses are not for everyone

A license to practice engineering is a privilege granted by a state to call oneself an “engineer” and to practice “engineering” before the public. In most states, these are protected terms having very specific meaning to the public. To become licensed as an “engineer”, an individual has to be willing to meet a minimum standard of education, experience, and examination to demonstrate their technical competence and their concern for the welfare of the public. The educational requirement is provided by an institution offering an engineering program that has been reviewed and accredited by the Accreditation Board for Engineering and Technology (ABET). The degree awarded by such an institution allows one to claim that one is a graduate of an accredited engineering program but not that one is an engineer. The experience requirement is satisfied by engaging in the “practice of engineering” as defined in the empowering statutes of each state engineering licensing board. The examination requirement is met by passing two eight-hour national examinations prepared by the National Council of Examiners for Engineering and Surveying (NCEES), which are offered twice each year. The philosophy and content of the national examinations is the subject of this article     

强调环保因素的产品设计原则

环保因素过去一直是一个不被重视的产品设计因素。但是近年来由于环保法规向产品生命周期的各个阶段的延伸,产品设计者不仅仅是在设计时考虑产品废弃后的环保因素,还必须考虑生产和使用时的环保因素。本文通过探讨产品与环保间的关系,尝试从环保的角度来探讨产品的设计特点;根据环保政策和法规的要求和消费者意识上的环保观念等差异分析产品设计,在产品设计阶段如何体现环保因素,并把环保因素与市场的卖点结合起来,使产品成为全生命周期的绿色设计产品。     

Transformer Fault Diagnosis by Dissolved-Gas Analysis

The great majority of incipient faults occurring in power transformers gives evidence of their presence early in their developmental stages. Oil and oil-impregnated electrical insulating materials can decompose under the influence of thermal and electrical stresses generating gaseous decomposition products which dissolve in the mineral oil. The nature and the amount of the individual component gases extracted from the oil may be indicative of the type and degree of the abnormality present [1]. One out of four transformers tested, using a gas chromatography technique, has an operational fault. Data obtained from the analysis of nearly 5000 transformers considers units ranging in size from 25 kVA-300 MVA. Case histories comparing fault diagnosis with actual conditions are cited. A method of determining the severity of the problem will be demonstrated. Over three years of experience using this method has proved the practical value of this chemical analytical tool to the power engineer.     

基于PC和PLC的工业压力测控系统的设计

本文设计了一种采用工控机和PLC的压力测控系统;介绍了该系统的软硬件及应用.该系统具有可靠性高和测量精度高的特点,能工作在自动,手动和调整3种模式.在检测压力的同时对机械臂的位移和移动时间进行检测,系统能够实时画出压力－位移曲线.数据和图片的保存也能大大方便后续的产品分析.该方法可用于众多行业的测控装置的设计.     

从焊接人员的国际认证解读工程教育和工程师资格国际互认的意义

企业要想参与国际间的竞争,首先就要解决产品的国际互认或认可,而人才在企业产品的生产中起着至关重要的作用,人才的国际互认至关重要。以我国焊接人员国际认证为主线,简述了我国高等工程教育的现状和发展趋势,论述了高等工程教育和工程师资格国际互认的意义。     

Ethics and standards in clinical engineering

The historical background of ethical issues in health care, leading to the establishment of standards by governing authorities, is traced. The types of standards and their scopes are examined. The ways in which the clinical engineer is involved with standards are discussed.     

Practicing engineering in a freshman introductory course

This paper discusses a teaching experience obtained in the undergraduate course of Control Engineering at the Federal University of Santa Catarina (UFSC), Brazil. The course endeavors to introduce the students to the university and to the real world of engineering and to develop an understanding of basic engineering concepts and foster professional skills. By introducing practicing engineering to the course from day one, student motivation is increased, and the relationship between theoretical and practical aspects of engineering is demonstrated more clearly. This "hands-on approach" allows the student a greater insight into the life of an engineer. It strengthens a weakness found in established teaching methods, allowing the individual to embark on his or her engineering education with greater confidence in his or her ability as an engineer.     

Product liability and the plant engineer: an introduction

The influence of jury verdicts in product liability lawsuits on both manufacturers and suppliers of a wide range of products is growing. Since this influence cannot be ignored, it should be consciously incorporated in as another design input. The major theories of product liability recovery are introduced, along with some suggestions on how to address certain of the concerns raised     

创新的高可靠性高频交流LED光引擎

介绍了光引擎的概念。给出了一种创新的小炫目LED光引擎的机械结构,以及由BP2808实现的高频交流光引擎电路拓扑。分析了该电路的工作原理及其具有的优点。指出这一专利产品具有广阔的产业化前景。     

对勘测设计过程有关人员工作职责的认识

讨论如何认识设计总工程师、副总工程师在工程勘测设计过程中的职责、相互关系以及产品的签署等,理清各方责任以避免出现管理缺位或越位。     

Human experimentation and medical technology

The various forms of protection devised by society for human subjects are examined. These are government regulation, informed consent, review at the local institutional level, and legal protection (malpractice suits). The related issue of how to define research is discussed.     

Digital Computer Approach to a Personal Information Retrieval System

The information "explosion" poses a challenging problem to the engineer or scientist interested in keeping up with his field. While many large-scale systems of information retrieval have been developed, there is a need for small-scale, personal information retrieval systems that may be easily used by an individual. This paper describes what the authors feel is a highly useful solution to this problem.     

The International Electrical Exhibition of 1884: A Landmark for the Electrical Engineer

The International Electrical Exhibition of 1884, sponsored by the Franklin Institute, was held in Philadelphia fromn September 2 to October 11, 1884. It recorded the past in a historical exhibit and bibliogaphical collection, displayed the present in exhibits of machinery and equipment for the production and use of electricity, and presaged the future in the first public display of a vacuum tube. In competitive tests, Edison's lamps burned for 1000 h but scrificed efficiency. The dynamos of Edison and Weston were tested and found to be equal in efficiency. Concurrent with the Exhibition, a quasi-governmental conference was held, attended by native and foreign scientists and engineer. At this National Conference of Electricans, the tension that existed between the pure scientist and the "practical electrician" becane evident. The science-technology relationship is suggested as one of the reasons for the founding of the American Institute of Electical Engineers (AIEE) in April 1884. The Exhibition is a convenient dividing line between a preelectrical wodd and one in which electric light and power became a fact of life in every aspect of our social and industril environment. It signaled the decline of the individual inventor as promoter of electricity and the begnning of dominance of the professional engineer within a corporate stucture, and showed the state of the electrical art at the time of the AIEE's first technical meetings. The need for a national society of electrdc engineers to receive "foreign electical savants, engineers and manufacturers" attending the Exhibition prompted N. S.     

并联Buck变换器反步均流控制律的设计

在电感电流连续导通的模式下,提出一种基于反步法的并联Buck变换器的均流控制方法。该方法在并联Buck变换器状态方程的基础上,引入一个表示电感电流间误差积分的状态量,然后拓展状态向量,得到拓展后的状态方程,针对该状态方程,根据反步法的原理,设计了并联Buck变换器的反步均流控制律。仿真结果表明,反步均流控制可以实现良好的均流效果,与自主均流控制相比,具有更强的鲁棒性。     

SDRAM控制器的设计及其应用

介绍了SDRAM存储器的工作原理及控制特点，描述了SDRAM控制器软核的设计方法，阐述了基于VHDL语言的状态机实现SDRAM控制器的关键技术，并给出了该控制器在HIRFL-CSR数据获取控制系统中的应用。     

Quest for understanding sciences

Understanding scientific principles generates many benefits. Comprehension is the key to creativity. It is highly unlikely that an individual without the command of basic principles will be the author of scientific breakthroughs. Understanding the conditions in which mathematical tools of science have been developed is the key to efficient research. The scientist or the engineer who lacks such understanding often ends up in dead end pursuits. Understanding the principles of operating machinery or apparatuses is the key to diagnosing their malfunctions. An individual who cannot come up with the correct diagnosis cannot be an efficient problem solver. Finally, the understanding of scientific principles by the general population is the best defense against fear of the unknown. This fear often stands in the way of technological progress and our improved well being as well. Armed with this insight, and pondering the questions that are seldom asked and even less often answered in science classes, the project CoLoS (Conceptual Learning of Science) was developed     

100-Gb/s optical communications

Optical communications is a quickly evolving field, driven by the ever increasing need for communication bandwidth. Over the next decade, the field is expected to mature substantially as high-speed components enable more advanced modulation and digital signal processing. With the standardization of 100-Gb/s Ethernet well in progress, terabit Ethernet is just over the horizon. As data rates continue to increase above 100 Gb/s, the role of the microwave engineer will become more and more critical to the success of next-generation optical communications gear. There is a tremendous opportunity for the radio engineer to migrate his or her skills to work in the field of microwave signal integrity. This is an up-and-coming field with lots of room for innovative research. In this article, the current state of the art and the research frontiers of 100 G optical communication systems is explained, and various optical modulation approaches are illustrated. Furthermore, comparison with traditional microwave communication systems is presented as well as the increasing role of the microwave engineer in high-speed optical communication design.