最新刊期
卷 ， 期 8 ， 1992
- 摘要：In this paper, a segment-rebuilding method for active networks is presented. The principle is that by dividing the active network into a lumped element subnetwork and device subnetworks, and by means of the indefinite scattering matrixes of subnetworks and the connections and terminating of floating ports, the scattering matrix of the active network is founded for analysis and design of the network. The method can be used to deal with active circuits with complex topology structure. Some examples are presented to illustrate the appli-cations of this method.关键词：Active Network;Network Segment;Rebuilding method2|34|1更新时间：2025-12-08
- 摘要：Based on （2） and （4）, two dual topological theorems in linear Active Networks areproved.A consequence of these theorems is discussed.关键词：秩;零度;策动点阻抗;输入阻抗;传输阻抗2|15|0更新时间：2025-12-08
- 摘要：A new channel routing model, while allows horizontal and vertical wire seg-ments to be placed on both layers, and two wires on different layer can be overlapped, is pre-sented. Based on this model, the constraints as well as the rules to layer assignment and routing order of nets in the two-layer channel routing are obtained. Then the property of opti-mal overlapping in a zone is analysed. By means of this property, the algorithm determines layer assignment and routing order of nets acoording to global optimat analysis. The routing area and number of vias are reduced much more than the router based on traditional Gv, Gh graph model. Preliminary experimental results are very encouraging. For the famous Deutsch’s difficult example, the algorithm obtains 18 tracks solution.关键词：CAD;layout;routing2|24|0更新时间：2025-12-08
- 摘要：The silicon bipolar transistors with poly emitter suitable for 77k operation are presented in this paper. Temperature models of current gain at different current injection le-vels are given. The results indicate that current gain decrease more rapidly as temperature falls at lower current injection level. The trapping effect of the shallow-level dopants on cut-off frequency with various injection condition is discussed.关键词：77K;Silicon bipolar transistors;Poly emitter;current gain;Cut-off frequency2|42|1更新时间：2025-12-08
- 摘要：Based on the piezoelectric model, this paper has studied the effect of piezoele-ctric charge on the depletion layer at channel/substrate interface of GaAs MESFET. It has been suggested that threshold voltage shifts of GaAs MESFET for positive piezoelectric char-ges are greater than those for negative. The interpretation of asmmetric inverse shifts of GaAs MESFET oriented in [011] and [011] directions is satisfactory.关键词：GaAs MESFET;Orientation effect;Backgating2|24|0更新时间：2025-12-08
- 摘要：Rate equations have been used for studying the dynamic response of a travelling-wave semiconductor laser amplifier （TWA） to a train of ultrashort optical pulses from an act-ively mode-locked semiconductor laser. The dynamic gain of the pulses acquired after passing the TWA and the carrier density distributions of the TWA have been found. The photon num-ber per pulse （corresponding to the pulse-energy） has been first used for studying TWAs.The dynamic gain saturation is determined only by the photon-per-pulse, regardless of input power. In addition, some issues concerned with the all-optical communication system have been dis-cussed.关键词：Semiconductor laser amplifier;Dynamic response;Carrier2|28|1更新时间：2025-12-08
- 摘要：<正> 四通4S（Super Sdence Setting System）高级科技书刊编排系统,是专门为科技类书刊文献的编排而设计的,排版功能实用性很强,采用即打即排的操作界面,直观形象,从根本上解决了科技书刊排版的难题。 4S系统具有文字、图片、数学、化学、乐谱、表格、杂志、造字等直观排版功能,可在24针打印机,不同精度激光印字机及激光照排机,输出与版式一致的样张,目前可提供包括宋、楷、黑、仿宋、魏碑、隶书、中圆、细圆、标宋等丰富的汉字字体。 四通4S先后荣获第37届尤里卡世界发明博览会金奖,北京首届国际博览会金奖,广州第二届国际2|9|0更新时间：2025-12-08
- 摘要：In this paper, we analyze the effects of mode partition characteristics of semi-conductor laser diodes on optical fiber transmission system, discuss the physical meaning of mode partition coefficient K and calculate the transmission bit rate, distance and corresponding power penalty for the system in different bit-error-rate asymptotic line, fluctuation level, wave-length and optical source spectrum.关键词：半导体激光器;光纤通信系统;传输性能2|33|0更新时间：2025-12-08
- 摘要：<正> 1992年5月底中电总公司预研局在电子科技大学（成都）主持召开了“3mm2048kb/s双工数字通信系统”技术鉴定会。该系统是继去年8月鉴定的“3mm64kb/s双工数字通信系统”之后的又一新技术成果。它标志着我国3mm数字通信技术已向实用化迈进了一大步。 该3mm数字通信系统由天线及3mm收发共容前2|19|0更新时间：2025-12-08
- 摘要：Based on the statistical distributions of the cepstral coefficients in the fea-ture space, this paper proposed a novel equivariance weighted cepstral distortion measure. Since the new weighting function reflects the fine structure of the feature space composed of speech cepstral vectors, the individual feature of speakers can be identified much efficiently. Preliminary experiments show that, for the VQ based speaker recognition, the proposed weighted cepstral distortion measure works substantially better than the Enclidean distance or the inverse variance weighted cepstral distance.关键词：Cepstrum;Distortion measure;Equivariance weighting;Speakor recognition2|92|5更新时间：2025-12-08
- 摘要：The neural net model, the feature extraction and the learning algorithm for the speech recognition by neural nets are investigated in this paper. A non-uniformly windowed pyramidical architecture is proposed, the normalizations of the feature vectors of two extraction algorithms are investgated and the Polak-Ribiere learning algorithm is modified to guarantee the weight vector not to converge to non-stable local minima. Speaker-dependent experments show that over 99% accuracy can be achieved for recognizing five vowels and ten digits. Speaker-independent experiments involved 90 speakers from 25 provinces of China show that 90.3% accuracy can be obtained for the digit recognition, and the performance can be increased by 1.0% after the pre-processing window is employed. The windowed model is more applicable for speech recognitions.关键词：neural net;learning algorithm;speech recognition;Speaker-independent.2|34|1更新时间：2025-12-08
- 摘要：A new adaptive transform image coding, which is based on the analysis of features for image edges and brain mechanism of vision, is presented in this paper. The image sub-blocks are classified according to the control information of the image edges in spatial domain firstly, then resampling, quantizing and coding are realized according to different features of these classifications in transform domain, particularly some rectangle filters are de-signed suitable to data compression of the image sub-blocks which are part of the lines and directional edges in the image. Finally, the results of computer simulation with the example of a standard image of human head and shoulder are given. The experimental results show that the subjective quality of the coding image is good and the PSNR reaches 33.9dB when the code rate is as low as 0.2bit/pel.关键词：Image edge;Transform code;Code rate;Source model;data compression2|19|2更新时间：2025-12-08
- 摘要：Because most FORTRAN programs spend most of their time inside loops, ef-ficient exploitation of the loop parallelism is one of the most crucial activities during progra-m parallelization. Although loop parallelization is researched extensively and deeply existing techniques do not handle loops in a satisfactory manner. In this paper, we present a new te-chnique exploiting the irregular parallelism across loop iterations efficiently and completely.关键词：Compiler;loop;Irregular parallelism;Self-scheduling;Iteration dependence graph;Hierarchical iteration dependence graph2|32|0更新时间：2025-12-08
- 摘要：Crystalline α-Si3N4 layer was formed by multiple N+ implantation into Si at high temperature, which omitted post high temperature annealing time. It is practically beneficail for simplifying working processes, lowering temperature and shortering time.关键词：Crystalline α-Si3N4;High temperature implanta tion;Multiple N+ implantation2|34|1更新时间：2025-12-08
- 摘要：In situ formation of YBa2Cu3O7x superconducting film on （100） YSZ single crystalline substrates by long-pulse laser （150μs , l.06μm） beam shooting at the YBa2Cu3O7-x target has been demo-nstrated. The temperature of substrate heater is 750℃. During deposition, the oxygen pressure in vacuum chamber is about 6 Pa. The thin films prepared by this technique are shiny and strong, and its zeroresi-stance temperature is 84.7K. These films have been analyzed by x-ray diffractometry and scanning elect-ron microscopy.关键词：长脉冲激光沉积;YBa2CuO7-x;超导薄膜;原位生成2|34|0更新时间：2025-12-08
- 摘要：An approach for CPM with noncoherent detection and 2-state trellis decoding is presented in this paper, and simulations are made for GMSK. It is shown that the bit error rate performance of GMSK, when decoded using noncoherent detection and 2-state trellis decoding, is far superior to the performance obtained using conventional one-bit differential detection.关键词：CPM;GMSK;Noncoherent detection and soft decision2|198|2更新时间：2025-12-08
- 摘要：In this paper a novel design method for high-order all-poles OTA-C low-pass filters is presented. The 2nd-order to 7th-order Butterworth extremely flat low-pass filters have been designed by the method and simulatively analyzed with SPICE. Meanwhile it is proved that the design method pre-sented in this paper is strict theoretically and useful in engineering design.关键词：filter;Transconductance;Simulation analysis;Frequency deviation;compensation2|45|1更新时间：2025-12-08
- 摘要：The recursive-composition method is employed to solve the transfer functions of nonlinear systems by use of the recursive relation of Volterra responses and the transfer function formulae of com-position systems concerned.关键词：非线性系统;传递函数;递推组合2|205|1更新时间：2025-12-08
- 摘要：The principle to construct hardware by which the fuzzy reasoning is ealized, is presen-ted in this paper. This hardware system can operate with analogous signal or discrite signal. It consists of far less fuzzy logical elements and has got high speed for real-time reasoning.关键词：Asynchronous modulation;real-time;fuzzy reasoning2|15|1更新时间：2025-12-08
- 摘要：A convolutional algorithm of number theoretic transiorms （NTT） for computing a long linear convolution is proposed in this paper. By use of sborter NTT, this algorithm can calculate long convolution in the overlap-add algorithm. It reduces tbe number of bit-shift and the word length of convolutional machine, so that a reduction in the execution time of convolution is obtained.关键词：Past algorithms;convolution;Number theoretic transforms2|89|1更新时间：2025-12-08
- 摘要：In this paper, on basis that lesolving real coefficient polynomial is difficult, we present a kind of new system of public-key cryplography on binary probability and multivariale probabability systems and give the measures for eliminating calculation error.关键词：概率公钥密码体制;二元概率体制;实多项式2|39|1更新时间：2025-12-08
- 摘要：<正> 由中国科学院半导体研究所与北京特种气体研究所共同对电子工业常用的8种电子级气体中六大类28种杂质进行了全面分析研究和质量控制。本工作始于1980年,现已获得了国际上领先的一整套分析技术。 1.8种电子级气体:N2、H2、O2、Ar、He、HCl、CO2、NH3中六大类分析技术水平如下:2|42|0更新时间：2025-12-08
- 摘要：<正> 该系列高纯水器由预处理、多介质过滤器、活性碳吸附、电渗析器、离子交换器、微过滤、紫外杀菌等组成,能除去天然水中的悬浮物、胶体、有机物、各种阳、阴离子、硅酸根,总有机碳、细菌、颗粒等杂质。出水电阻率≥17兆欧（25℃）。杂质含量优于美国ASTM—EI级2|27|0更新时间：2025-12-08
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