汉语自动标引加权方法试验研究

本文介绍了几种自动标引加权方法,以及把这几种方法应用于汉语文献自动标引试验的情况,给出了试验的有关数据、基于数据的分析和推出的结论,并对汉语科技文献自动标引中的若干问题进行了探讨。     

A 155 Mbps laser diode driver with automatic power and extinction ratio control

An integrated laser diode driver(LDD) driving an edge-emitting laser diode was designed and fabricated by 0.35 μm BiCMOS technology. This paper proposes a scheme which combines the automatic power control loop and temperature com-pensation for modulation current in order to maintain constant extinction ratio and average optical power. To implement tem-perature compensation for modulation current,a novel circuit which generates a PTAT current by using the injecting base current of a bipolar transistor in saturation region,and alternates the amplifier feedback loop(closed or not) to control the state of the current path is presented. Simulation results showed that programmed by choice of external resistors,the IC can provide modu-lation current from 5 mA to 85 mA with temperature compensation adjustments and independent bias current from 4 mA to 100 mA. Optical test results showed that clear eye-diagrams can be obtained at 155 Mbps,with the output optical power being nearly constant,and the variation of extinction ratio being lower than 0.7 dB.     

PLC对继电器控制线路的改造

PLC是英文“ProgrammableLosicController”的缩写词,中译名为“可编程控制器”。可编程控制器是集计算机技术、自动控制技术、通信技术为一体的新型自动控制装置。其性能的优越,已被广泛地应用于工业控制的各个领域。PLC的优点：1）可靠性高,抗干扰能力强。2）适应性强,应用灵活。3）编程方便,易于使用。4）功能性强,扩展能力强。     

A prototype of workflow management system for construction design projects

1 Introduction 1 In recent years there is a growing understanding of the importance of effective design management to facilitate a coordinated building design within budget, and to ensure the smooth operation of a project [1]. Therefore, it becomes a certain tendency that management of construction design project should combine with information technology (IT) to approach information share and process integration. Since the application of computer-aided design technology (CAD) in China at la…     

Automatic generation method of geological cross-sections in dredging engineering based on 3D solid NURBS models

An automatic generation method of geological cross-sections in dredging engineering based on 3D geological solid models is presented.The 3D geological models are built applying the non-uniform rational B-splines(NURBS) technique,and a 2D profile can be calculated and generated automatically through Boolean operation to meet the demands of dredging projects.Moreover,an automatic marking method for geological attributes is put forward based on database technology,and the geological attributes include the profile name,scale,horizontal and vertical relative coordinates,geological lithology,and 2D standard lithology legend.At the same time,the automatic marking method can also provide an interactive mode for geological engineers to edit and modify the profile in the modeling system.Practical engineering applications show that the automatic generation method is a simple,flexible,fast and precise visual graphics rendering process that can create 2D standard profiles automatically and efficiently.This method also provides a convenient support tool for geological engineering digital analysis.     

本刊启事

为进一步提高办刊质量。本刊自2012年5月起,将正式启用"中国知网学术不端文献检测系统"与"万方数据论文相似性检测系统"。检测系统可有效检测来稿是否存在抄袭、伪造、篡改、一稿多投等多种学术不端行为,并自动生成检测报告。凡有不端学术行为的稿件,编辑部将不予采用。     

程序化自动选择预测模型的一种思路

在预测活动中合理选择预测的模型，既是预测成功的关键，也是预测过程中最感困难的一步。对于企业经营管理活动迫切需要的预测技术，难以广泛普及的因素之一就是预测模型能否科学、合理的选择。利用计算机软件程序化的自动选择预测的模型，进而做到科学的智能化预测，是实现这一目标的一个突破点。本文是在这个方面的一个尝试和努力。     

哈德公寓给排水及消防设计

随着多功能、综合性公寓建筑的日趋繁多,各种管道布置较为复杂,使设计工作难度加大;哈德公寓是由大庆油田有限工程公司承担的设计项目,本文通过对哈德公寓的介绍,展示了一个综合性公寓的设方案和设计过程,总结了本工程的设计特点。     

基于STM32的太阳能自动寻光系统

文章中系统基于STM32芯片,设计并制作了一个用于精确跟踪太阳并收集能量的系统。系统由STM32F103ZET6最小系统、光信号采集转换卡、追踪太阳部分、电压采集等几部分组成。该系统通过光信号采集转换卡感知太阳位置,同时采用跟踪算法增强稳定性,实现精确跟踪。为了便于携带,整体结构设计为可拆卸的装置。选用了大容量的锂电池作为蓄电池,可以极大的解决当前多种数码产品的充电问题。     

加油机检定技术中的问题研究

加油机是机动车添加燃油的液体体积测量系统。加油机的量值是否准确也是百姓关心的重点民生计量部分。做好对其的检定工作,不仅可以保护顾客的基本利益,还能够保护国家燃油财产。文章着重对加油机检定技术当中的几个问题进行了研究,希望能够为加油机检定效果的准确性提供保障。