最新刊期
卷 ， 期 3 ， 1987
- 摘要：On the basis of attributed grammars, a model of knowledge based system is proposed. The model is basically an attributed tree-like structure. It not only has the context-sensitive properties concerned in the structure, but also can introduce the heuristic knowledge. The construction of the model is similar to the construction of the pattern in syntactic pattern recognition. The model structure may be transformed into executable LISP program. Two examples of expert system design are given to illustrate applications of the method.2|49|1更新时间：2025-12-08
- 摘要：TLMM thin film capacitors have firstly been manufactured by depositing PbO2 semiconducting film with MnO2 on Ta2O5 media. The characteristics of TLMM capacitor are low dissipation factor and small temperature coefficient shift. Auger spectra analysis shows that the least dissipation factor of capacitor is 0.1-0.3% （1kHz） and the temperature coefficient is 201.5±3.5ppm/℃（-4070℃） when Pn: Mn: O = 30: 20: 50.2|33|2更新时间：2025-12-08
- 摘要：A new transform convolution is developed to reconstruct the 2-D picture from projection data. Projection data is obtained from an integration of the reflectivity coefficients of the objects along the circular arc of the wavefront with a radar beamwidth. Such a circular arc is encountered when ground-based radar is used to observe planets, asteroids, or even comets if the Earth’s rotational velocity is large compared to the gross movement of the target. It is expected that the new algorithm can be used to reconstruct images for the curvature of the wavefront.2|34|7更新时间：2025-12-08
- 摘要：The refractory metal silicide is considered as a new technique instead of doped polysilicon. A new technique of forming silicide of titanium is introduced in this paper.Ti+ are implanted into LPCVD polysilicon film and followed by thermal annealing in H2 to form TiSi2. The relation of TiSi2 forming condition with ion implanted dose and energy is given. Experimental results show that the sheet resistance of TiSi2 film is down to 0.95Ω/□, corresponding bulk resistivity is 26μΩ-cm. This value is less than that of ordinary doped LPCVD polysilicon by one order of magnitude. The microstructure of Ti silicide was studied with X-ray diffraction and TEM electron diffraction. The distribution of depth profile of Ti in polysilicon and composition of titanium silicide were analysed by AES and SIMS.2|36|0更新时间：2025-12-08
- 摘要：An unified configuration method is provided. It is of an optimum alignment configuration and is suitable for any number of antennas. An analytical expression for maximum separation is given. The essentials of linear-array arrangement are summarized.2|47|0更新时间：2025-12-08
- 摘要：This paper describes a SDS-2 multifunction e-beam scanning system in which the combination of analog and digit scanning is used. The triangular wave instead of the sawtooth wave is used to reduce the requirement of the high frequency response of the deflection amplifier. The analogous scanning speed is 1mV100mV/μs, and the address resolution is 15 bit per axis. All the scanning field adjustments are automatic. Experimental exposure has been practised in the 20×20mm2 scanning field with smooth skewed vector at 2μm.2|20|4更新时间：2025-12-08
- 摘要：A numerical solution of the scattering characteristics of wet ice sphere is made by dyadic Green’s function method. The extinction cross section, scattering cross section and absorption cross section of the wet ice sphere as a function of radius parameter k0a0 and water layer thickness are calculated, and these results are compared with corresponding results of the ice sphere and water sphere. The differential scattering cross section of wet ice sphere as a function of the zenith angles and two azimuth angles φ=0° and φ=90° are discussed for two wavelengths λ =2.5cm and λ=0.868cm.2|46|1更新时间：2025-12-08
- 摘要：The effect of quantization distortion of the differential gain（DG）and differential phase （DP） in digital color TV systems is analysed. Two cases are taken into account. One is that the sampling frequency and the color subcarrier frequency are non-synchronized and the other is that the sampling frequency is three times the subcarrier frequency. For the former case, exact and approximate formulas for calculating DG are obtained. For the latter case, the influence of sampling phase can easily be seen from the calculated formulas of DG and DP. Methods of reducing measuring error caused by quantization distortion are discussed.2|36|1更新时间：2025-12-08
- 摘要：This paper presents the method for calculating the probability of accepting at each acceptance time point and the probability of rejecting on each time interval in the sequential tests so that the operating characteristic curve can be computed recursively. Then three exact formulae for calculating the expected test time are derived and proved briefly equivalent each other. Finally, a synthetic expression for sequential test calculation is derived, from which OC, ETT and confidence limit on the MTBF can be calculated.2|26|2更新时间：2025-12-08
- 摘要：The PCL transport equation is obtained by combining the transient large signal coupling equation of non-resonant degenerate four-wave mixing with the transport equation of an ordinary laser in this paper. The stability of the intensity of output light of a CW PCL, the temporal behavior of the intensity of output light of a pulse PCL, the property of the CW self-pumped PCL in a stable atate as well as the optimum coupling of CW externally-pumped PCL are discussed.2|18|0更新时间：2025-12-08
- 摘要：The multi-port theory that is superior to the conventional signal-flow graph theory for multiple-loop feedback amplifiers and is simpler in computational methods and clearer in physical significance for general linear feedback network analysis is presented, and from it the topological formulas can be derived.2|36|1更新时间：2025-12-08
- 摘要：Some upper bounds for the numbers of fuzzy switching functions of n and n + 1 variables are revealed further and can be expressed respectively as2|9|0更新时间：2025-12-08
- 摘要：In this paper, the analysis of noise perfomance and gain associated, the judgement of stability and the synthesis of optimum signal source impedance of GaAs FET are discussed by means of a lumped-element equivalent circuit. The results show that there is a sound agreement between the theortical computation and the experimental data.2|13|0更新时间：2025-12-08
- 摘要：The mapping from one- to multi-dimensions for DFT and circular convolution algorithms are discussed from the viewpoint of finite commutative rings. The relation between multidimensional DFTs mapped from one-dimensional DFT and Levy-Walsh transforms is described. The necessary and sufficient conditions for a one-dimensional DFT or circular convolution to be expressed as a multidimensional DFT are given, and then a fast algorithm for index mappings is presented.2|71|0更新时间：2025-12-08
- 摘要："Mutual energy theorem" and the concept of inner product of electromagnetic fields are intruduced, on which the method of expansion of radiation field in spherical waves is discussed.2|57|2更新时间：2025-12-08
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The Self-Adaptive Mesh Refinement Technique for the Finite Element Analysis of Semiconductor Devices
摘要：A self-adaptive mesh refinement technique for the finite element analysis of semiconductor devices is given. The computation shows that such technique can considerably reduce the number of mesh points and non-linear iterations. Thus the computation cost is decreased and efficiency of devices analysis is improved remarkably.2|43|3更新时间：2025-12-08 - 摘要：In this paper the definitions of GF（2）-vector and GF（2）-matrix are given, and some properties of GF（2）-matrixes are discussed. GF（2）-matrixes are used in place of Searle Operations①, （?）i, ①i, and the matrix analysis is applied to Logical Fast Walsh Transformation.2|13|2更新时间：2025-12-08
- 摘要：In thi paper two viewpoints are presented firstly for surveying the modernization of the telecommunications of a country. In the discussion of the developments of telecommunications in China one should pay attention to the 3 characterizations. They are: (1> China is a rapidly developing and great country; （2） although the territory of China is about the same size as U. S. A., yet the traffic demands in these two countries will not be same in long term; （3） though the existing telecommunication networks do not satisfy the requirements of the national economy and the needs for cultural and daily life of the people.but they would be rather efficiently utilized and improved than abandoned. Then, the developing history and present conditions as well as the proposals for the development of the telecommunication techniques are discussed from three aspects. They are from the networks, from the channels and from the equipments. This paper implies the importance of the strategy for the development. Also, the review and suggestions in principle are the strategies. At the conclusion, it is pointed out that the develpment of telecommunication techniques must be closely in accordance to the mentioned characterizations.2|59|0更新时间：2025-12-08
- 摘要：QD-3182 linear circurt voltage noise test instrument has been developed. Several measured results for low frequency voltage noise density in high precision linear integrated circuit are given and compared with each other. The voltage noise densities in our super-β device measured at 10Hz, 100 Hz and 1kHz are 4.0nV/Hz,2.0nV/Hz and 1.5nV/Hz respectively.2|56|0更新时间：2025-12-08
- 摘要：The measurement approach to noise parameters of FET and bipolar transistor is given and semi-automatic F-P test equipment are introduced in this paper. The final noise parameters Fmin, Rn, GOP and Bop can be obtained in 1.6 GHz frequency by means of this equipment and microcomputer.2|42|0更新时间：2025-12-08
- 摘要：A method for recognition of handprinted Chinese characters is presented. As the start point of this method, it is revealed that the essential features are existed in stroke structure of the characters, which make different characters distinguishable. The extraction and analysis of strokes and their structure relations of characters are emphasized. Chinese characters are finally described by a simplified form to implement recognition. The preliminary experiment on 500 Chinese characters obtains satisfactory result.2|61|1更新时间：2025-12-08
- 摘要：<正> 1987年3月9—12日在重庆召开了第二届全国多值逻辑学术会议。围绕着多值逻辑的理论探讨与应用展开了讨论。共交流了71篇论文,达到了预期的效果,这是一次有生气的学术会议。主要特征是:参加会议的人们了解到我国多值逻辑基础理论、逻辑设计理论与电路设计等已具有一批相当水平的成果。在新理论、新技术探索上已跟上不断前进的国际步伐,有些新理论研究已取得国际领先的成果。使我国多值逻辑研究的专家加深了对当前发展方向2|11|0更新时间：2025-12-08
- 摘要：The difference between oxygen intrinsic gettering wafer and commonly polished wafer is investigated using the measurements of DLTS and I-V. After the I-G treatment, I-G wafers have excellent properties in negative bias, but a deep level trap centers of Ec-0.49（eV） has been found. The results show that I-G technique has good function in gettering, but it damages crystal structure and the deep level trap centers.2|24|0更新时间：2025-12-08
- 摘要：In this paper, the technique of fast-acquisition phase-locking for Derived Rate Rejection（DRR） is complemented by calculating and phase-plane drawing. For developing the above theory, the calculating formulas for pull-in band and the pull-in time are deduced. Finally, the modified type ORR PLL is proposed. The results of computer aided calculation show that the modified type loop in which the pull-in time can be further reduced is superior to the DRR loop.2|14|1更新时间：2025-12-08
- 摘要：This paper points out that the formula of the power spectral density of Markov sourses cited by Lindsey and Simon is in conflict with certain known modulated signal and the correct conclusion is presented.2|88|0更新时间：2025-12-08
- 摘要：<正> 中国科协“电与信息科学技术联合会”于3月20日正式成立。联合会是科协下属的一级学会自愿参加的学术性横向联合体,而不是各学会之上的一级组织。它主要负责开展跨学科、跨专业、跨学会的全国性的和国际性的学术活动。参加这个联合会的学会有中国计算机学会、中国电子学会,中国电工技术学会、中国电机工程学会、中国自动化学会,中国通信学会等六个组织。会上一致推选中国电子学会理事长孙俊人为联合会第一任主席。中国电机工程学会理事长毛鹤年,中国电工技术学会理事长高景德,中国通信学会2|10|0更新时间：2025-12-08
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