管具螺纹的数控加工及修理技术应用

从现场实用的角度对比分析了手动、数控2种修螺纹方法,提出了在管具修理工作中研究推广数控技术车修管螺纹的必要性,介绍了试验研究过程中的技术问题。     

Teaching-Material Design Center: An ontology-based system for customizing reusable e-materials

Use of electronic teaching materials (e-material) to support teaching is a trend. e-Material design is therefore an important issue. Currently, most e-material providers offer a package of solutions for different purposes. However, not all teachers and learners need everything from a single package. A preferable alternative is to find useful material from different packages and combine them for a particular course. Currently, most educators collect the material manually, which is time-consuming and may result in missed material. In this paper, we describe a system – the Teaching-Material Design Center, which follows the standard of Sharable Content Object Reference Model – to separate e-material for use as teaching templates and learning objects and to label the material with use of semantic metadata for searching. This system can find existing teaching templates and learning objects for e-material designers and provide a convenient environment for constructing customized e-material for different requirements. We describe the implementation and evaluation of the proposed system for a course. Our system is efficient in finding teaching templates and learning objects and shortening the e-material development process.     

地震钻机调速系统

介绍自行设计的针对WT－50W型液压式地震钻机的调速系统，较为全面地提供该系统的控制电路原理和执行机构、解脱装置、操纵机构的方案。     

Unix tools as visual programming components in a GUI‐builder environment

Development environments based on ActiveX controls and JavaBeans are marketed as ‘visual programming’ platforms; in practice their visual dimension is limited to the design and implementation of an application's graphical user interface (GUI). The availability of sophisticated GUI development environments and visual component development frameworks is now providing viable platforms for implementing visual programming within general‐purpose platforms, i.e. for the specification of non‐GUI program functionality using visual representations. We describe how specially designed reflective components can be used in an industry‐standard visual programming environment to graphically specify sophisticated data transformation pipelines that interact with GUI elements. The components are based on Unix‐style filters repackaged as ActiveX controls. Their visual layout on the development environment canvas is used to specify the connection topology of the resultant pipeline. The process of converting filter‐style programs into visual controls is automated using a domain‐specific language. We demonstrate the approach through the design and the visual implementation of a GUI‐based spell‐checker. Copyright © 2001 John Wiley & Sons, Ltd.     

用于一维图像识别的支撑矢量机方法

研究了支撑矢量机的分类机理,并利用支撑矢量机对雷达目标一维像进行了识别.识别的结果表明了该方法的优越性,并显示它可以对残缺不全的样本进行识别.     

Influence of load and speed on wear characteristics of grey cast iron in dry sliding — selection for minimum wear

The wear of grey cast iron in dry sliding conditions has been studied with the aims of (1) finding the influence of working conditions on the wear rate, and (2) determining the region of speed and load where low wear is accomplished. Grey cast iron with flake and nodular graphite was submitted to investigation using a pin-on-disc machine. The results indicate that the flake graphite cast iron is more suitable for applications at speeds greater than 4 m s⁻¹ and lower loads, while nodular cast iron has greater wear resistance at lower speeds in the range of loads investigated - from 50 N cm⁻² to 200 N cm⁻²     

Improvement of Air-Distributing System of the Pneumatic Impact Machines for Trenchless Technologies

The process of actuation is considered for the inertial element in the improved air-distributing system of pneumatic puncher whose dimensionless parameters are determined.     

轮式工程机械的行驶平稳性

根据振动理论建立了振动力学模型,并用等效刚度方法分析研究了弹性悬挂轮式工程机械行驶平稳性和振动特性。     

一种简易的容积式灌装机

介绍了一种用于液体产品分装 ,易于使用的容积可调式灌装机的工艺原理及主要部件的结构     

基于支持向量机的岩爆识别模型

岩爆的发生受多种因素的影响,这些因素关系错综复杂,以不同的特征和组合对岩爆产生综合影响,为科学、充分地利用现有的有限工程资料,本文从地下洞室围岩最大切向应力、岩石的单轴抗压强度和抗拉强度以及岩石冲击倾向指数四个主要因素出发,提出了基于支持向量机的岩爆识别模型,较好地解决小样本、非线性、高维数、局部极小点等的实际问题。