Progress in electrophotography in Western Europe

A review is given of the progress in electrophotographic science and technology in Western Europe during the years 1967 to early 1971. University research work is mainly directed towards two areas: 1) the electrical and physical properties of photoconductors, such as selenium, chalcogenides, oxides, and organic materials; and 2) the sensitization of these photoconductors. Industrial research teams report on the preparation of electrophotographic layers on development and on image evaluation. A bibliography including scientific papers and patents published on this subject during said period completes this review.     

智能通信在楼宇自控系统中的应用

随着计算机技术、控制技术、通信技术及信息技术的飞速发展,人们对生活、办公环境安全性、舒适性的要求日渐增长,智能建筑应运而生。楼宇自动化控制系统是智能建筑的一个重要组成部分。通过结合具体的智能楼宇控制工程项目,在介绍系统概况的基础上,给出了系统的总体设计方案及子系统的监控方案,具有一定的实用价值。     

Advances in millimeter-wave subsystems in Japan

The authors describe the development trends and results of millimeter-wave systems in Japan in such fields as communication, radar, and measurement systems. The applications included are the W-40G waveguide transmission communication system, an automobile traffic control system using the 60-GHz band, a collision avoidance radar system for an automobile, a plasma electron density measuring system, and satellite communication. The authors describe the development of devices such as high-power FET amplifiers, traveling wave tube amplifiers (TWTAs), IMPATT amplifiers, low-noise amplifiers, and monolithic microwave integrated circuit (MMIC) devices used in constructing the millimeter-wave systems     

中国带电清洗技术的突破

一、电路故障的成因 通常,由于空气的污染和设备所处的环境及管理条件不同,空气中的灰尘、油污、酸碱及其气体、盐分、潮气、炭渍、金属尘埃、各种机械杂质等污染物质,不可避免地吸附在电路表面及其它部位,加之静电累积和在电场力的作用下,污秽的累积不断加重和变得牢固,各种污秽牢牢附着在线路表面,深层及各部位。灰尘、油污、酸碱及其气体、盐分、潮气、炭渍、金属尘埃、各种     

Telecommunications in Malaysia: diversity in adversity

The telecommunications industry in Malaysia has experienced a tremendous transformation in just over a decade. The government-owned Jabatan Talikom, which hitherto operated the network, was incorporated in 1987 and subsequently privatized a few years later, with a majority share holding by the government. The regulatory aspects were spun off under the slim looking JTM. This marked the beginning of liberalization, and many new players entered the fray. This article reviews the telecommunications infrastructure and services available in Malaysia and visits some of the telcos offering these services. Some pertinent issues affecting the industry are also discussed     

Losses in small-radius bends in single-mode fibres

Refractive index profiles and mode field radii determine small-radius bending losses in single-mode fibres. Losses in six different types of fibres were measured in bends with radii ranging from 1.25 to 8 mm. The results show that a refractive index depression in the core centre reduces the bending-loss sensitivity.<>     

Rearrangements in cell populations in malignant growth

It is emphasized that one of signs of malignant growth is heterogeneity of cell population which arises at the earliest pretumour stages and determines the character of tumour progression. At the same time by means of selective influences on population of malignant cells it is possible to change their quantitative correlation and to obtain rearrangement of the normal cell interrelations. Initiation of the tumour, its progression and regression are considered on the basis of the population-cell rearrangement, typical of each of them separately. The concept of the unity of the carcinogenesis and anticarcinogenesis processes is also formulated.     

General Trend in Electrical Communications in Japan

Systems are currently being designed for higher reliability and greater economy. Larger transmission capacity is required to meet a rapid increase in recent communication demands instigated by the introduction of video and information communications facilities. More flexibility, to deal with the variety of communication modes to come, and smaller hardware dimensions, to overcome situations caused by the high population density, seem to be particularly sought in the communication technology of Japan. Research and development concentrate on these objectives. The following is an explanation of the present state of the art and general trends in this country.     

Progress in display-device development in Western Europe

A review of the basic research and industrial development of display devices in Western Europe during the years 1968 to early 1973 will be given. The display types considered are: 1) active displays such as cathode ray tubes, light-emitting diodes, electroluminescence cells, and gas discharge devices, and 2) passive displays such as laser displays, light valves, and ferroelectric and liquid-crystal devices.