ISDN的现状和发展

９０年代将是ＩＳＤＮ和宽带ＩＳＤＮ迅速发展的年代，本文介绍了国外Ｎ－ＩＳＤＮ和Ｂ－ＩＳＤＮ的发展动向，并结合我国通信网的现状，对发展ＩＳＤＮ（Ｂ－ＩＳＤＮ）提出若干建议。     

Voigt线型的微分消卷积

通过频域内的近似处理得到了洛仑兹线型微分消卷积的实用算符。推广到高斯、洛仑兹线型的复合情形即Ｖｏｉｇｔ线型，亦可得到它的消卷积算符。把所得算符应用于单峰、多峰情形，对各种不同的组合形式，分别得到了消卷积谱，其分辨率提高因子Ｋ与复合线型中洛仑兹成分的多少有关。     

Machining with tool–chip contact on the tool secondary rake face—Part II: analysis and discussion

The forces, chip thickness, and natural tool–chip contact length in machining with a double-rake-angled tool are predicted in Part II of the present study. It is revealed that in comparison with a single-rake-angled tool, a double-rake-angled tool increases the forces, especially the thrust force. However, the increase in chip thickness and tool–chip contact length is not significant under the input conditions specified in the present study. The effect of seven input variables of the proposed model is quantitatively investigated. The predicted variations of forces, chip thickness, and natural tool–chip contact length are in good agreement with theoretical and experimental results obtained by other researchers. The interrelationships among the resultant force, the chip thickness, and the natural tool–chip contact length are established, which provides a new and promising method to estimate the tool–chip contact length by employing the resultant force. It is demonstrated that the model can also be extended to study the problem of machining with a groove-type chip breaker tool.     

低相噪,低杂波数字锁相环路滤波器的设计

较详细地分析数字锁相频率合成器的相位噪声，着重用控制论方法对低相噪、低杂波锁相环的环路滤波器进行设计，并用某Ｓ波段频率合成器的实验结果进行了验证。     

压水堆堆芯换料设计优化的研究

讨论压水堆堆芯换料设计优化问题，并研制一套实用的换料优化软件包，可用于低泄漏、外－内和改进的外－内装料方案的优化。在低泄漏方案优化时，利用哈林原理将燃料组件布置与可燃毒物配置的优化问题脱耦成两步优化问题。先用线性规划方法进行无可燃毒物时燃料组件布置的优化，然后再用可变容差法寻找可燃毒物的优化布置。应用该软件对秦山核电厂首次难芯换料方案进行了优化，提出了可供参考的一些优化布置方案。     

Formation mechanism of bainitic ferrite and carbide

Superledges on the broad faces of bainitic ferrite plates have been observed with transmission electron microscope (TEM). The observed superledges, ranging from less than 1 to 24 nm in height, are imaged in three dimension by way of tilt operation under TEM. Also, an array of smaller superledges are observed to pile up in front of a secondary phase. Pileup of superledges in front of a barrier is indicative of the mobility of an individual superledge. The precipitation of carbide associated with bainitic ferrite is also studied. It is observed that a carbide of a wedgelike shape may exist in front of a superledge with its tip(i.e., thinner end) penetrating the austenite and its root (the other end) originating at α:γ boundary. This condition indicates that the observed carbides may nucleate at the austenite side of α:γ phase boundary and grow toward austenite matrix. This article is based on a presentation made at the Pacific Rim Conference on the “Roles of Shear and Diffusion in the Formation of Plate-Shaped Transformation Products,” held December 18-22, 1992, in Kona, Hawaii, under the auspices of ASM INTERNATIONAL’S Phase Transformations Committee.     

New efficient designs for XOR and XNOR functions on the transistorlevel

Two new methods are proposed to implement the exclusive-OR and exclusive-NOR functions on the transistor level. The first method uses non-complementary signal inputs and the least number of transistors. The other one improves the performance of the prior method but two more transistors are utilized. Both of them have been fully simulated by HSPICE on a SUN SPARC 2 workstation     

大电流监测信号提取的光收发及信号处理

近年来,大电流的监测成了人们十分关心的问题,这是由于大电流有强磁、高压、电流大等一系列的直接监测所不能克服的问题。这就需要把高压大电流的强电信号,经过提取后变成能在实验室中直接观测的弱电信号。为此,如何从高压大电流的信号中提取出随实时信号变化而实时变化的小信号就变成了一个关键问题。详细介绍了监测信号提取的光收发电路原理和后续信号处理电路,分析了各部分的作用,给出了必要的分析结果。     

下一代网络--多协议标记交换MPLS思想剖析

多协议标记交换MPLS通过在传统的IP包里加入标记，使原来依赖于IP头标分析的路由转发转变为依赖于标记的转发，这不仅可以大大地提高IP包的转发速度，更可使传统IP网络具有QoS能力。本文深入分析了标记转发的思想．并指出了MPLS实现其优点所用的机制与原理。