中国炼铁系统的节能与环境保护

回顾了20世纪90年代以来,中国炼铁系统的节能和环境保护的进展.指出由于高炉喷煤技术的开发和推广,大大减少了焦炉的建设投资,真正从源头减少了铁前系统的能耗和污染.基于对炼铁系统二次能源的分析,从节能和减排温室气体来看,淘汰落后的小烧结、小高炉, 大力推广高炉TRT、高效干式除尘和利用高炉煤气发电及烧结余热回收利用等,将是今后工作的重点.     

Performance prediction of a hybrid‐excitation synchronous machine with axially arranged excitation poles and permanent‐magnet poles

This paper presents a method of predicting the steady‐state performance of a new hybrid‐excitation synchronous machine (HESM) theoretically. The field pole of this HESM is axially divided into two parts; one is an excitation part and the other a permanent‐magnet (PM) part. A nonlinear equivalent circuit, which can include the saliency of the rotor and the magnetic saturation due to the iron core, is derived. Based on this equivalent circuit, the steady‐state performance of the HESM is calculated, and the results are confirmed through experiments. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 150(2): 43–49, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20033     

System for Sewing Machine Industry Standard Innovation——Constructive Research for a Technical Standards System for Sewing Machines

Constructive research of a market-oriented industry's system of technical standardization by redefining those technical standards is the basis of innovation. Through considering and implementing innovation of the industry's standards,rapid development and standardization of the industry can be achieved.     

武钢 10000 m3/h制氧机主冷泄漏故障处理及应急保产方式

氧气生产单位保用户用气一旦出现较为紧张的局面时，如何正确处理保安全生产运行、保用户生产、安排抢修时间三者之间的关系，值得关注与研究。     

市县HFC系统如何选择和使用光端机

对有线电视工程设计中如何选用优质设备、提高网络质量等问题进行探讨     

Information-Based Evaluation Criterion for Classifier's Performance

In the past few years many systems for learning decision rules from examples were developed. As different systems allow different types of answers when classifying new instances, it is difficult to appropriately evaluate the systems' classification power in comparison with other classification systems or in comparison with human experts. Classification accuracy is usually used as a measure of classification performance. This measure is, however, known to have several defects. A fair evaluation criterion should exclude the influence of the class probabilities which may enable a completely uninformed classifier to trivially achieve high classification accuracy. In this paper a method for evaluating the information score of a classifier's answers is proposed. It excludes the influence of prior probabilities, deals with various types of imperfect or probabilistic answers and can be used also for comparing the performance in different domains.     

钻机绞车滚筒体的窄间隙埋弧焊

针对钻机绞车滚筒体采用手工电弧焊工人劳动强度大、焊接效率低、质量不稳定及返修率高等问题,研制了钻机绞车滚筒体窄间隙埋弧焊专机。该专机由ESAB—A2埋弧焊电源和焊接小车、窄间隙焊头、滚轮架、防窜装置、旋转地线夹、三维焊接工作台、焊剂自动回收机组成。使用表明,采用该焊机焊接的滚筒体焊缝质量完全符合设计要求,合格率100%,焊接效率比原来提高6倍。每件滚筒体的焊接可降低人工成本约80%。     

Evaluating the design of flexible manufacturing systems

Evaluating the design of flexible manufacturing systems is complex. Developing a measure of performance useful for evaluating alternate designs continues to be interesting. Here, total productivity of the system is proposed as an appropriate measure. Specification of parameters based upon strategic considerations for this measure are discussed. Finally, the usefulness of the measure is demonstrated through an example.     

Numerical modelling for scattering of waves in three-dimensional cracked material

In this paper, a mathematical model is proposed for the problem of the scattering of plane waves in a three-dimensional cracked materials. Instead of obtaining closed-form solutions as in conventional theoretical analysis methods, this approach, called the Equivalent Nodal Force (ENF) method formulates the mechanical effects of cracks as an equivalent nodal force in a numerical procedure, and physically translates cracked material into an equivalent continuous one. Several mechanical relations between waves and cracks are evident from this method. Also the results of several numerical calculations are presented and these are compared with those obtained by the conventional methods.     

RLL码的计算机辅助设计

本文着重讨论计算机辅助设计RLL码的具体实现问题.该过程首先根据RLL码两个参数d,k确定一个编码率p/q,然后构造出RLL码的高阶状态转换-输出符号矩阵并求相应的近似特征向量.最后通过状态分裂和状态归并过程,即可得到一个满足d,k约束的编码输出表.其中状态转换-输出符号矩阵为实现计算机辅助设计RLL码提供了有效的数据结构,而且要优化RLL码编码器,就必须有选择地进行状态分裂.