CPLD在雷达伺服轴角编码电路中的应用

介绍一种针对正、余弦旋转变压器—数字转换器(RDC)模块，用复杂可编程逻辑器件(CPLD)技术实现伺服轴角编码电路设计的方案。分析了轴角编码器系统中14XSZ系列旋转变压器—数字转换器的原理、轴角粗精组合原理及轴角纠错原理。详细介绍了CPLD的内部功能电路、CPLD轴角粗精组合和纠错实现电路，以及CPLD的工作时序图。提出了利用CPLD实现轴角粗精组合处理的方案，并通过了实际系统运行的考验，证明该方案可行。     

肝癌碘油栓塞后肝区平片所见碘油沉积量与疗效关系

本文分析了90例肝癌肝动脉灌注化疗碘油栓塞后,肝区平片所见碘油沉积量和疗效的关系。碘油沉积分为多,中,少三组,从ATP下降,肿瘤缩小率及一年生存率三方面比较。结果沉积多的与中等组三项都有显著差别;沉积中等的与少的组差别不明显。说明碘油沉积要达到一定的量后,疗效才会显著提高。同时分析了影响碘油沉积的几个因素。     

X波段及DBS接收用PHEMT单片低噪声放大器

报道了X波段及DBS接收用单片低噪声放大器的研制结果。利用CAD软件对单片电路进行优化设计，设计工作包括MBE材料、PHEMT器件和单片电路三部分。在研制过程中，开展了关键工艺的专题研究。研究结果为：单级单片放大器在10：5－11．6GHz范围内，NF≤1．82dB，G≥7.72dB；在11．7－12．2GHz范围内，NF≤1．80dB，G≥6．8dB；双级放大器在10．4－11．1GHz范围内，NF≤1．96dB，G≥15．3dB，最低噪声系数为1．63dB，最高增益为16．07dB。     

加气混凝土切割机的特性与选用

文章分析了我国目前生产加气混凝土制品的各种切割工艺及采用的切割设备--地翻型切割机、空中翻转型切割机、长杆式切割机、预铺式切割机、压入式切割机、栅条式切割机(JQS)钢带式切割机的工艺特点.介绍了选用这些切割机应注意的问题,指出必须结合实际的生产工艺、产品要求及场地特点、投资大小合理选择切割机.     

冶金厂房钢吊车梁设计中一些问题的探讨

对双层翼缘板焊接工型钢吊车梁的某些受力特征、吊车梁的支座节点连接构造设计等进行了较详尽的分析,提出了满足冶金工业厂房大跨度、大吨位吊车梁系统受力和工艺要求的方法.     

安钢集团信息化实施策略探讨

近年来，为了更好地应对新的市场挑战，钢铁企业都在积极推进信息化建设，以实现管理提升、效益提升的目标。本文结合安钢集团的实际情况，对信息化实施策略进行初步的探讨，希望能对企业信息化建设有所借鉴。     

Novel algorithms for shared segment protection

The major challenges in designing survivable schemes are how to allocate a minimal amount of spare resources (e.g., bandwidth) using fast (e.g., polynomial-time) algorithms, and, in case a failure occurs, to be able to recover quickly from it. All existing approaches invariably make tradeoffs. We propose novel shared segment protection algorithms which make little or no compromise . We develop an elegant integer linear programming (ILP) model to determine an optimal set of segments to protect a given active path. Although the ILP approach is useful for a medium-size network, it is too time consuming for large networks. Accordingly, we also design a fast heuristic algorithm based on dynamic programming to obtain a near-optimal set of segments. Although the heuristic algorithm has a polynomial time complexity, it can achieve a bandwidth efficiency as high as some best-performing shared path protection schemes and, at the same time, much faster recovery than these shared path protection schemes. The proposed scheme is also applicable to a wide range of networking technologies, including Internet Protocol and wavelength-division multiplexing networks under the generalized multiprotocol label switched framework.     

Achieving fast and bandwidth-efficient shared-path protection

Dynamic provisioning of restorable bandwidth guaranteed paths is a challenge in the design of broad-band transport networks, especially next-generation optical networks. A common approach is called (failure-independent) path protection, whereby for every mission-critical active path to be established, a link (or node) disjoint backup path (BP) is also established. To optimize network resource utilization, shared path protection should be adopted, which often allows a new BP to share the bandwidth allocated to some existing BPs. However, it usually leads the backup paths to use too many links, with zero cost in term of additional backup bandwidth, along its route. It will violate the restoration time guarantee. In this paper, we propose novel integer linear programming (ILP) formulations by introducing two parameters (/spl epsi/ and /spl mu/) in both the sharing with complete information (SCI) scheme and the distributed partial information management (DPIM) scheme. Our results show that the proposed ILP formulations can not only improve the network resource utilization effectively, but also keep the BPs as short as possible.     

含氮杂环季铵盐缓蚀剂在CO2-3%NaCl溶液体系中的电化学行为

为控制CO2腐蚀，合成了含氮杂环季铵盐缓蚀剂9912-1，通过电化学实验，研究了该缓蚀剂在CO2-3％NaCl-H2O体系中对碳钢于25℃和90℃下的缓蚀行为。实验结果与挂片失重法测试的结果基本一致。低温下缓蚀效果优于高温下的缓蚀效果。而且该缓蚀剂与硫脲有很好的协同效应。Tafel曲线表明，该缓蚀过程是以控制阴极腐蚀为主，并对其缓蚀机理进行了初步探讨。     

一种可切削玻璃陶瓷的压痕断裂特性

将断裂韧性测试的压痕方法与压痕弯曲方法相结合，独立地分离出了压痕残余应力因子ｘ，使其成为可测参量，并建立了压痕一压痕弯曲的断裂韧性测试方法．将这种方法应用于一种可切削玻璃陶瓷的测试，获得的Ｋ１ｃ值为Ｋ１ｃ＝２．０３ＭＰａ·ｍ１／２，与单边切口法（ＳＥＮＢ）获得的Ｋ１ｃ值有较好的一致性．测得的残余应力因子Ｘ＝０．０９３，符合Ａｎｓｔｉｓ经验公式的预测．