最新刊期
卷 ， 期 2 ， 1980
- 摘要：The Shewhart’s control charts, which were first introduced in 1924,can be used to distinguish between product-quality variations caused by chance and assignable causes. But there is a more general process, in which it is necessary to further divide the assignable causes into those we are interested and those we are not, and then select out the former and exert control over them. However, the Shewhart’s control charts cannot distinguish between these two classes of assignable causes.A new type of control charts called selecting control charts is given in the present paper, which can give alarm only to the assignable causes we are interested and neglect those we are not interested.The idea of selecting control charts is fundamentally different from that of the Shewhart’s ones, the former can distinguish one more class of assignable causes than the latter.The selecting control charts have succeeded in controlling the overlimit rate and the register-return rate of long-distance calls. The anomaly determining accuracy of these new control charts is about tea times higher than that of Shewhart’s control charts.These new control charts will find widespread use in both commercial and industrial areas.2|118|17更新时间：2025-12-08
- 摘要：In demodulation type transponder the demodulated baseband signal accompanied by noise is used for further modulation and retransmission. The relationships between the retransmitted noise and system parameters are analysed for three cases, i.e. coherent demodulation in linear channel, coherent demodulation with pre-limiter and frequency discrimination demodulation. The theoretical analysis has been confirmed by experiments. Results of, this article can be used for radio system design of orbit determination and data transmission.2|24|0更新时间：2025-12-08
- 摘要：In this paper, the major factor which affects the noise of a device is theoretically analysed from the equivalent circuit in which the trap effects at the interface between the GaAs expitaxial layer and the substrate are considered. The noise figure in the range of device design versus the elements of the equivalent circuit, the geometrical structure of the device, the material parameters and the operation frequency are described. The new planar devices using oxygen implantation are developed. Submicron gate lengths have been fabricated, by using conventional compensated contact photolithography. The microwave noise of the resulted device is much lower than that of the general mesa device. The noise figure of 3.5dB at 12GHz with associated gain of 5dB have been obtained. S-parameters of 2 to 12GHz are also presented. Mean time to failure of the device have been extrapolated to give 2×107 hours. The application experiments, such as that of oscillator, the mixer and the microwave low-noise amplifier at 2 to 12GHz, have been done, and the primary successful results have been achieved.2|24|0更新时间：2025-12-08
- 摘要：This paper presents calculations on spectral distribution of output noise power of a recursive-DMTI cascaded with DFT. The decrease in SNR due to using DMTI also is calculated. It has been proved-that the decrease in SNR is very small in the clutterless region and the increment of the decrease is not evident when the number of single pole networks for DMTI increases. The spectrum of output noise power’ is uniform. This will lead to appropriate implementation in the radar signal processing system.4|20|0更新时间：2025-12-08
- 摘要：In this paper, a charge pumping effect in CCD with floating diffusion region is introduced, which will lead to a voltage shift and a special charge transfer loss. With such an effect, floating diffusion amplifier can not be taken as a nondestructive voltage sensor of a signal. The effect can be obviated provided that floating diffusion is reset to a critical voltage during charge transfer process.2|25|0更新时间：2025-12-08
- 摘要：The typical current and voltage waveform of TRAPATT diode as well as its inherent physical parameters and operating parameters are investigated in this paper. The normalized impedance, power output, efficiency and characteristics of the harmonics in the large nonlinear range are analysed by using the frequency domain method. The requirements of impedance match between the device and the circuit in various operating conditions are obtained. The maximum possible efficiency of TRAPATT diode is estimated. The numerical calculations are given with some typical parameters of the device and the circuit in S-band as an example, and characteristic curves for different working conditions are plotted. The results, show that measured values of circuit impedance are close to those calculated from typical waveforms.2|18|0更新时间：2025-12-08
- 摘要：By adjusting phase setting in phase shifters, sidelobe level of the pattern of phased array antenna can be reduced. Such is the phase weighting method d?scribed in the paper. Its basic concepts and theoretical analysis have been described and comparison has been made with density-weigh ting method. Also two examples have been given.3|215|8更新时间：2025-12-08
- 摘要：This paper studies the three-dimensional logic structure. Several properties and theorems of directed graphs of three-dimensional array are derived, and the logic of ternary cell structure is designed by applying these theorems and properties. Finally, by comparison with binary cellular array, it is proved that this structure for the implementation of simulating the superior function of man will be of great value. It is possible to become a new concept of the"very VLSI".2|20|6更新时间：2025-12-08
- 摘要：In noise measurement the problem of noise transmission in the two-port networks in cascade is frequently met with. Each stage of the network itself will contribute its noise whereas it will Jose the noise power transmitted from the former stage. The noise can be exactly measured only when its loss and contribution in the network have been defined.This article analyses the loss and generation of noise in the network by means of the concept of the available power transmission coefficient, and derives the formula for noise transmission in the lossy . two-port networks in cascade. This formula has been applied to determine the available noise temperature of the thermal noise standard source.3|56|1更新时间：2025-12-08
- 摘要：In this paper it is proposed that space electronics covers the fields of radio electronic technics for the tracking and control of the artificial satillites and spacecrafts, for the observation of the earth by satellites, for the exploration of deep space, for satellite communications and broadcasting, and for the uti-lization of satellites for position fixing of moving objects. Some outstanding achievements of space electronic systems are cited in this paper, and the features special to space-electronics are stated and analysed. The development of space-electronics in our country is briefly described. Finally the future prospects of space electronics are concisely discussed.4|45|0更新时间：2025-12-08
- 摘要：From the view point of field sources and the idea of "computer analogy" of electrostatic induction process,a new approach to characteristic impedance calculation of TEM transmission lines is: presented. The problems of various transmission lines with different cross sections may be solved by a simple and unified method. The accuracy of calculation is high enough for practical purposes.2|93|1更新时间：2025-12-08
- 摘要：A new approach with which the order of harmonics can be derived from double-sampling in the automatic microwave frequency counter is presented. Using electronic gate-control computing technique and simplified analog circuit, automatic and digital measurement of frequency with high accuracy and speed is possible. On the basis of this approach, a series of microwave frequency counter products are developed, with an upper limit of frequency measurement up to 60GHz.2|27|0更新时间：2025-12-08
- 摘要：This paper describes the development of two types of CCD MTI cancellers. One is a four channel parallel-operation system with sampling frequency of 2.1 MHz. In this system the .clocks between adjacent CCDs are alternated in lower frequency overlapping mode. The system is very suitable for narrow pulse radars. Tke other is a single channel two pulse canceller with sampling rate of 250kHz.This system can successfully be applied to wide pulse radars.2|42|1更新时间：2025-12-08
- 摘要：The experimental results of the high pressure KrCl Excimer laser pumped by transverse discharge are reported. The gas mixture used is HCl:Kr:He = 2.5:160:1500 and the total pressure varies from 2 atm. to 2.5 atm. The maximum Output energy is 6mJ in a 14cm3 volume. The specific energy density is 0.4J/1. The electric efficiency is 0.12%. In this device, the ArF laser action is observed too, in NF3:Ar:He = 2.7:270:1500 gas mixture at a total pressure of about 2 atm. .,2|25|0更新时间：2025-12-08
- 摘要：This article briefly introduces the designing idea of the language TL in which a text is described, and the HCP system for implementing the TL. By means of using the HCP system, the automatic-generation of compilers of multi-languages can be achieved.2|15|0更新时间：2025-12-08
- 摘要：<正> 为配合我国卫星电视广播事业的发展,南京固体器件研究所采用该所器件研制成功并小批量生产了全固态化直播卫星电视接收机,第一批样机已于1978年9月模拟试收成功,1979年经过全面检测考核后,通过了部级技术鉴定。 该所研制的第一台这种高灵敏度电视接收机,其天线直径为3.5m,包含有参放、本振、下变频器2|31|0更新时间：2025-12-08
- 摘要：<正> 中国科学院半导体研究所研制的N沟MOS 4096位动态随机存贮器,采用了先进的N沟硅栅等平面工艺和单管单元电路。集成度为10875个元件/片,管芯成品率超过20％。 为提高集成度,缩小芯片面积和提高电路性能,除简化电路外,还对各单项工艺进行了较深入的研2|16|0更新时间：2025-12-08
- 摘要：<正> “螺旋耦合型慢波结构的研究”（以下简称为“研究”）一文,利用多导体传输线方法对螺旋耦合型慢波结构进行了理论分析。其中用一个简化公式计算了矩形螺旋线各段导纳与翼片导纳,进而计算了大量的色散和耦合阻抗曲线。大家知道,在多导体传输线分析方法中,导纳的计算对色散和耦合阻抗是十分重要的,尤其是耦合阻抗直接与导纳的大小成反比。通过研究,我们认为该文在计算各段导体的导钠时,假2|19|0更新时间：2025-12-08
- 摘要：<正> 我国著名电子学家、教育家、全国五届人大代表、全国劳动模范冯秉铨教授,积劳成疾,不幸于一九八○年三月六日在广州逝世。整个电子学界都在怀念他。 冯秉铨教授生前身兼多职。他是中国电子学会、声学学会副2|34|0更新时间：2025-12-08
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