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The purpose of this paper is to design a current transformer model based on the principle of B-dot. It can reflect the change of transmission line current and meet the requirement of automation and intelligence for current measurement in power system.

In this paper, a new type of current transformer is designed on the principle of B-dot, which has the structure of the inverse series of planar air core coils and the form of printed circuit board (PCB). With this structure, the current transformers can induce magnetic field quite well. The finite element simulation for the current transformer with n layers structure is conducted in the Maxwell, which help to optimize the design of the current transformer.

By setting up the experimental platform, the experiment of the current transformer is carried out. The results of the test show that the measurement accuracy can satisfy the requirement of measurement. Besides, the new current transformer has good transient characteristics and can meet the needs of the development of smart grid.

The new type of current transformer is based on the principle of B-dot, which is designed with a new type of non-contact PCB hollow coil current transformer. It has no iron core, no ferromagnetic effect and the phenomenon of ferromagnetic resonance. It has great progress in its insulation performance, volume and bandwidth response. In addition, the planar hollow coil of the inverse series structure can make the structure more accurate.

The purpose of this paper is to outline the basic principles of inductive position sensors.

The paper explains one company's advances in inductive position technology in detail, together with some of the applications for which they are now suitable.

It is shown that concentrating on high volume applications in market sectors such as automotive, user interfaces, and utility metering, where the low cost of these sensors and their moderate accuracy (typically<1 percent of full scale) offers an attractive price/performance ratio.

An original and useful contribution direct from an international technology consulting, product development, and intellectual property [IP] licensing organisation with a reputation for successfully commercialising emerging science and technology. Which, for more than a decade, has made innovations in inductive position sensors and developed application‐specific sensor systems.

Heady growth gives way to steady expansion in Japan, as some makers turn their eyes to the potentially lucrative job of electronics assembly. John Hartley reports.

Increased automation and improvements in cost‐effective volume production techniques have, paradoxically, created additional difficulties when small quantities of printed circuit boards are required. There is consequently a growing interest in bench top and small modular equipment capable of producing high quality boards. This market, once almost exclusively confined to research and development laboratories, has extended rapidly throughout universities and polytechnics, government agencies and manufacturers of all types of electrical and electronic equipment. The impracticability of introducing small quantities into a volume production unit has extended the usefulness of such equipment to the “in‐house” facilities of the high volume printed circuit board manufacturers themselves.

Mass soldering has not entirely replaced manual soldering and it is possible to enumerate various applications of the latter. The basic tool for the manual process is the soldering iron, with its vital major component, the bit. Parameters to be taken into account include power available at the bit, maximum bit temperature, thermal capacity and recovery time. Considerable detail is provided on the criteria that govern the choice of soldering iron bits, and a few useful soldering aids described. Although individual styles of hand soldering emerge, following the preferred practice should guarantee reliable joints. After an outline of the optimal operating procedure, some information is given on touch‐up, desoldering and structural joints. This article is an extract from the book “Handbook of Printed Circuit Design, Manufacture, Components and Assembly” by G. Leonida, published by Electrochemical Publications Limited, 8 Barns Street, Ayr, Scotland.

I was an invited speaker to the ISHM‐Benelux meeting. As I arrived early, I also sat in on the committee meeting as an observer. Jos B. Peeters was the outgoing president and the incoming committee was widened to about 15 members compared with the previous 6. Following the unanimous election of all those nominated, the committee reconvened and elected Mr Kwikkers as the new president of ISHM‐Benelux. He is a professor at the Technische Hogeschole in Delft.

Printed Circuit Brush A new Long Life Scotchbrite Printed Circuit Flap Brush with improved board cleaning characteristics at a lower cost per unit of production has been introduced by the Scotchbrite Industrial Products group of 3M. The brush comprises single sheets of mineral impregnated Scotchbrite web, cut to length and firmly attached at a 90° angle to a fibre core. The mineral and resins used in the material construction assure a consistent cut with higher levels of output and a longer running time.

At present, one of the key equipment in pillar industries is a large rotating machinery. Conducting regular health monitoring is important for ensuring safe operation of the large rotating machinery. Because vibrations sensors play an important role in the workings of the rotating machinery, measuring its vibration signal is an important task in health monitoring. This paper aims to present these.

In this work, the contact vibration sensor and the non-contact vibration sensor have been discussed. These sensors consist of two types: the electric vibration sensor and the optical fiber vibration sensor. Their applications in the large rotating machinery for the purpose of health monitoring are summarized, and their advantages and disadvantages are also presented.

Compared with the electric vibration sensor, the optical fiber vibration sensor of large rotating machinery has unique advantages in health monitoring, such as provision of immunity against electromagnetic interference, requirement of less insulation and provision of long-distance signal transmission.

Both contact vibration sensor and non-contact vibration sensor have been discussed. Among them, the electric vibration sensor and the optical fiber vibration sensor are compared. Future research direction of the vibration sensors is presented.

Describes the benefits and application of hot air staking for assisting the assembly of plastic parts and including the fixturing of pcbs, springs, bearings and a wide variety of other components. Describes the various forms and patterns of stakes that can be used and the methods of hot air heating and forming.

This article aims to provide details of recent developments in robots that can change shape and self-reconfigure.

Following an introduction, this article first describes some recent developments in shape-changing materials and then considers a selection of shape-changing robots. It then discusses self-reconfiguring robots and describes a unique self-unfolding robot. Finally, concluding comments are drawn.

This article shows that research into true shape-changing robots is still at an early stage and several very different strategies are being studied. Novel materials are expected to play a key role in many designs and potential applications include search and rescue, health care and surveillance. Self-reconfiguring modular robots are at a more advanced stage and while many can reconfigure to adopt varying shapes and gaits, the ability to accomplish differing tasks in manufacturing is still some way in the future. Overall, the various classes of shape-changing robots being studied represent a move towards a new era in robotic capabilities, but despite many recent technological advances, considerable further work is required before these become a practical reality.

This article provides an insight into recent technological advances in shape-changing and self-reconfiguring robots.