网上产品信息发布的方法综述

讨论了网上信息发布在未来企业发展中的意义 ,详细阐述了图片形式、动画形式、二维工程图形式、VRML形式、影像式虚拟现实形式、三维造型形式等多种发布和浏览方法 ,并对其中的关键技术进行了简要介绍 ,并给出了某些产品信息发布和浏览的实例     

滤波反投影算法的数值实现问题研究

提出了滤波反投影算法的数值实现形式.从傅立叶中心切片定理引出了FBP算法的连续形式;而后提出了滤波实现的离散形式,并从定积分的数值实现和信号与系统论两个角度加以证明,接着提出了基于新普生公式的反投影实现形式.     

网上产品信息发布的方法综述

讨论了网上信息发布在未来企业发展中的意义，详细阐述了图片形式、动画形式、二维工程图形式、VRML形式、影像式虚拟现实形式，三维造型形式等多种发布和浏览方法，并对其中的关键技术进行了简要介绍，并给出了某些产品信息发布和浏览的实例。     

塑料注射模标准件的选用

在阐述了模具标准化意义的基础上,介绍了常用注射模标准零件的形式及应用场合,以及标准模架的结构形式、尺寸组合及标准模架结构形式、尺寸组合选用的方法。     

机械传动技术的改进与发展

机械传动技术是机械制造业研究的重要领域之一,机械传动技术的改进一方面要注重新的传动形式的开发,另一方面也要注重传统传动形式的改良。现重点介绍了新时期传统蜗轮蜗杆传动形式的不断优化和改进,并阐述了磁力传动这种新机械传动形式的主要特点以及存在的问题。     

水电站合拢焊缝接头形式研究

坝后式引水压力钢管取消伸缩节后合拢焊缝接头形式有对接和搭接两种接头形式。对两种接头形式进行了试验研究,结果表明:对接和搭接两种接头形式都有各自的特点,对接接头形式优点较为明显,采用一些工艺措施可以减少焊接拘束应力和防止裂纹的产生,采用对接接头形式有利于引水压力钢管安全运行。     

各种压缩形式综合对比与分析

横向介绍了暖通行业各种压缩形式的技术特点,同时纵向介绍了螺杆机、离心机和永磁同步电机的关键技术,从原理和结构两个方面对各种压缩形式进行了分析比较,对选择压缩形式有很大的帮助。     

焦炉捣固机的改进

分析了现有捣固机的结构形式、工作原理及其使用中发现的问题,阐述了改进后用直线电机驱动捣固机的结构形式、工作原理和优势,并对两种形式的捣固机做了对比。     

无库式潮汐能发电设备发展及其轴承应用

介绍了潮汐能发电设备的结构形式和发展状况,主要讨论目前已经具备样机的海底风车式和贯流式潮汐能发电机组,研究了这2种形式的潮汐能发电设备中各部位的轴承应用条件,并讨论了适用于该工况的轴承结构形式。     

挤压工艺中组合凹模的设计

通过对常用组合模具三种形式的对比,分析其不同形式下的受力情况,为组合模具的形式选取及简易设计提供了依据.     

Analysis of Tribochemical Surface Damage by Image Processing (Analysis of Tribochemical Damages)

In the work, the problem of automated classification of tribochemical damage of metallic surfaces based on digital image processing was considered. Five types of tribochemical wear damage, including fretting, smearing damage, combinations of oxidation and erosion wear, and wear in corrosive media were investigated. Initial images were characterized by a set of texture features. The effectiveness of using the developed method for automated identification of tribochemical surface damage types was demonstrated.     

General Radiation Damage Problems for Lubricant and Bearing-type Materials

The actual mechanism of radiation damage to materials by reactor radiation is a matter of prime importance. Radiation damage to covalent compounds such as organic lubricants by reactor radiation is due primarily to secondary ionization caused by fast neutrons, slow or thermal neutrons, and gamma rays, and is not largely due directly to the initial interaction of any of these three types of radiation with the nuclei or atoms of the organic compounds. The amount of energy absorbed by a given material from these various types of radiation can be calculated, and the actual damage incurred is a function of the energy absorbed. Based upon available experimental test data of radiation damage to various organic materials and based upon the equivalent absorbed energy-equivalent damage concept, various generalizations regarding organic lubricating materials can be made.     

Visualization of cellular DNA crosslinks by atomic force microscopy

Cellular DNA crosslinks are a type of DNA damage induced by toxic chemicals or high‐energy radiation. If damaged DNA is not rapidly repaired, cells will die or mutate. To evaluate the types of DNA damage and their influence on vital cell activities, it is necessary to be able to detect DNA crosslinks. To date, indirect methods such as alkaline elution, potassium chloride–sodium dodecyl sulfate assay and comet assay have been used to detect DNA damage. Direct morphological observation, on the other hand, may be a useful tool to differentiate the types of DNA damage. In this report, atomic force microscopy (AFM) has been employed to visualize the breakage and crosslinking of cellular DNA strands in cells treated with formaldehyde and hydrogen peroxide. Our results showed that toxic chemical‐induced crosslinking of cellular DNA occurred in a dose‐dependent manner. DNA conglomerates were observed with high concentrations of formaldehyde, and the AFM observations were consistent with those of a comet assay. Our experiments demonstrate that AFM is an efficient method to differentiate the types of DNA damage. SCANNING 31: 75–82, 2009. © 2009 Wiley Periodicals, Inc.     

Erosion damage in engine bearings

Erosion damage in engine bearings has until recently been of little more than academic interest with insignificant effect on bearing performance. However, over the last four or five years, erosion damage in plain bearings has become more prevalent. The types of erosion damage are categorised and common features examined.     

加筋板广布疲劳损伤的剩余强度分析

给出加筋板广布疲劳损伤的两种损伤类型和两个剩余强度判据,剩余强度判据是净截面塑性区屈服判据和裂尖韧带屈服判据.给出蒙皮带有多裂纹和蒙皮带有多裂纹且桁条也带有裂纹时应力强度因子的近似工程估算方法.文中也给出加筋板含多裂纹时剩余强度净截面塑性区屈服判据和裂尖韧带屈服判据的表达式及塑性区尺寸估算方法.对三种损伤的加筋板进行剩余强度试验,指出多裂纹尤其是桁条也带裂纹时剩余强度降低较多.用上述两种判据进行加筋板广布疲劳损伤剩余强度预测,预测结果和试验结果比较符合.     

Damage detection and quantification using transmissibility

Structures experience various types of loads along their lifetime, which can be either static or dynamic and may be associated to phenomena of corrosion and chemical attack, among others. As a consequence, different types of structural damage can be produced; the deteriorated structure may have its capacity affected, leading to excessive vibration problems or even possible failure. It is very important to develop methods that are able to simultaneously detect the existence of damage and to quantify its extent. In this paper the authors propose a method to detect and quantify structural damage, using response transmissibilities measured along the structure. Some numerical simulations are presented and a comparison is made with results using frequency response functions. Experimental tests are also undertaken to validate the proposed technique.     

轴类零件的损坏及修复工艺技术

轴类零件是组成机器的重要零件,而油田各种轴类零件损坏后将严重影响油田设备的正常运转。首先介绍了油田常用轴类零件损坏类型与原因,然后介绍了油田生产中尝试的几种轴类零件修复工艺,最后对修复工艺进行了示例剖析。     

广布疲劳损伤加筋板结构剩余强度分析

广布疲劳损伤（widespread fatigue damage，WFD）对老龄飞机是非常重要的问题。文中用工程方法和有限元方法计算含广布疲劳损伤（WFD）加筋板的剩余强度，完成3种类型9件加筋板的剩余强度试验。计算结果和试验结果比较吻合，能满足工程精度的要求。结果还表明，WFD明显降低了加筋板的剩余强度。     

船舶损管监控系统的研究与开发

针对影响船舶安全的各种损害隐患问题,对船舶损管监控系统的必要性、功能、组成、原理、架构、硬件和软件等方面进行了研究,对基于损管监控台、现场控制设备及数据处理设备、各类传感器及执行机构的管理层、控制层、数据层三层控制模型进行了归纳,提出了基于传感器、可编程逻辑控制器和损管监控台的船舶损管监控系统,利用半实物仿真试验、陆上联调试验和实船应用对该监控系统的性能、功能、环境适应性和电磁兼容进行了测试。研究结果表明,该系统可实时监控各种损害隐患状态,提高了船舶损害隐患的管控水平,保证了船舶的安全性、可靠性。     

Shakedown analysis of beams using nonlinear kinematic hardening materials coupled with continuum damage mechanics

The nonlinear kinematic hardening theory of plasticity based on the Armstrong-Fredrick model and isotropic damage was used to evaluate the cyclic loading behavior of a beam under the axial, bending, and thermal loads. Damage and inelastic deformation were incorporated and they were used for the beam shakedown and ratcheting analysis. The beam material was assumed to follow the nonlinear strain hardening property coupled with isotropic damage. The effect of the damage phenomenon coupled with the elastoplastic nonlinear kinematic hardening was studied for deformation and load control loadings. The Bree's diagram was obtained for two different types of loading, and all numerical results confirmed the reduction of the safe loading domain due to material damage.