柴油机"飞车"与"游车"故障分析与诊断维修

以“飞车”与“游车”的形成机理为切入点，着重分析了柴油机“飞车”及“游车”的故障症状、原因，提出了对疑难故障的诊断检修方法。     

推行"零库存"和"配送制"管理实施"日历作业制"的实践与体会

结合大齿集团自2000年以来，推行“零库存”管理和“配送制”，确保生产按市场拉动实施“日历作么制”的实残，阐述了“零库存”、“配送制”和“日历作业制”的推行给大齿集团生产管理带来巨大变化的过程和体全，并提出今后进一步提升生产(物流)管理水平，确保市场和用户满意的设想。     

"H型密封装置"和"往复自换向密封活塞装置"简析

液压缸密封技术长时期以来一直在“O”型圈、“V”型圈、和“Yx”型圈等以及以“O”型圈为基础的组合式密封件中发展，现在终于有了结构的突破。本文介绍“H型密封装置”和“往复自换后密封泛塞装置”。     

认证机构亟待"认证"

认证机构趁“需”而出 “ISO9000国际质量体系认证”是国际标准化组织（ISO）发布的质量保证标准，是世界公认的质量体系认证依据，其质量保证的范围覆盖科研、生产、检验、服务等各个方面，是目前国际上最全面、最完整的质量保证体系。 随着我国加入WTO，企业界使出浑身解数向WTO的规则靠拢，于是“认证热”便悄然兴起。 随着“认证热”的兴起，为企业提供质量技术服务的认证、咨询管理机构相继催生，且愈来愈多。但大批的认证机构趁“需”而出，必然使我国的认证市场鱼龙混杂，真假难辨。上世纪末，全国虽然只有几家质量认证机构…     

受控机构优化的"二步综合法"

提出了“视角”、“位置角”、“轨迹区内”、“轨迹区外”的基本概念；针对受控机构精确实现“多点”轨迹的特点。建立了精确实现“多点”轨迹受控机构的优化模型；提出基于Windows奈件下的复合形法，求以补偿运动的位移为目标函数的优化解的方法；实例计算表明，该方法是实用可行的。     

摩擦领域试用"摩圣"技术

一种对金属摩擦件表面进行有效修复的技术———“摩圣”技术 ,已在我国机械、电力、石化等部门试用。国家经贸委节能信息传播中心日前将其纳入“最佳节能实践”案例。“摩圣”技术是采用多种弥散的极微细矿物质组成的混合物 ,添加多种辅料和催化剂。“摩圣”技术的作用过程是 :在使用该技术的最初阶段 ,金属零件发生了接触表面的超精加工磨合 ;“摩圣”向金属零件内部扩散 ,改善了金属本身的晶体结构 ;在局部接触点超高温、高压作用下 ,“摩圣”粒子被“熔合”到金属表面层晶格 ,在微观起伏的低凹处发生“摩圣”、金属粒子和其他参与摩擦物…     

单片机系统中的"看门狗"技术

本文研究了单片机应用系统中软件、硬件“看门狗”技术，给出了硬件“看门狗”的基本电路以及强制复位“看门狗”电路及控制策略，并从提高单片机工作可靠性的角度来分析了各种“看门狗”方案的优缺点。     

我国力促"中国制造"转向"绿色制造"

我国已是世界“制造大国”,但不是“制造强国”。特别是资源能源消耗量大,加剧了我国资源能源短缺和环境污染形势,并面临日益严峻的国际绿色贸易壁垒。9日公布的国家科技支撑计划提出,要通过实施“绿色制造关键技术与装备”重大项目,力促向“绿色制造”转变。     

免费链接"中国物料搬运工业"网站

“中国物料搬运工业”网站已开通,网址为ｈｔｔｐ://ｗｗｗｍｈｉｃｃｏｍｃｎ。为使该网站成为我国物料搬运行业的信息交流平台,特开设了很多有专业特色的栏目,“网站精选”是其中之一,在该栏目下设有“国外杂志”、“国外组织”、“国外公司”、“国内公司”等分栏目,上面列出的栏目都是与行业密切相关的,为使行业厂自己的网站获得更多的点击次数,我们可免费将其链接在“国内公司”分栏目下。如感兴趣,请将有关信息发至以下电子信箱ｉｎｆｏ@ｍｈｉｃｃｏｍｃｎ。免费链接“中国物料搬运工业”网站     

"密封"与"密封工程"的概念

本文提出“密封工程”的观点,“密封工程”包括涉及密封概念的政策,法规,标准,技术,管理,教育和培训等内容。阐述了树立“密封工程”观点的目和意义,指出树立密封工程观点,有利于增强环境保护意识,推动密封技术进步 。     

Minimal Realization of Linear Graph Models for Multi-physics Systems

An engineering system may consist of several different types of components,belonging to such physical"domains"as mechanical,electrical,fluid,and thermal.It is t...     

INTEGRAL EQUATION METHOD＇S APPLICATION IN HOLE-EDGE STRESS OF COMPOSITE MATERIAL PLATE WITH DIFFERENT SHAPED HOLES

The strength of composite plate with different hole-shapes is always one of the most important but complicated issues in the application of the composite material. The holes will lead to mutations and discontinuity to the structure. So the hole-edge stress concentration is always a serious phenomenon. And the phenomenon makes the structure strength decrease very quickly to form dangerous weak points. Most partial damage begins from these weak points. According to the complex variable functions theory, the accurate boundary condition of composite plate with different hole-shapes is founded by conformal mapping method to settle the boundary condition problem of complex hole-shapes. Composite plate with commonly hole-shapes in engineering is studied by several complex variable stress fimction. The boundary integral equations are founded based on exact boundary conditions. Then the exact hole-edge stress analytic solution of composite plate with rectangle holes and wing manholes is resolved. Both of offset axis loadings and its influences on the stress concentration coefficient of the hole-edge are discussed. And comparisons of different loads along various offset axis on the hole-edge stress distribution of orthotropic plate with rectangle hole or wing manhole are made. It can be concluded that hole-edge with continuous variable curvatures might help to decrease the stress concentration coefficient; and smaller angle of outer load and fiber can decrease the stress peak value.     

Non-monotonic material contrast in scanning ion and scanning electron images

30 keV Ga⁺ focused ion beam induced secondary electron (iSE) imaging was used to determine the relative contrast between several materials. The iSE signal compared from C, Si, Al, Ti, Cr, Ni, Cu, Mo, Ag, and W metal layers does not decrease with an increase in target atomic number Z₂, and shows a non-monotonic relationship between contrast and Z₂. The non-monotonic relationship is attributed to periodic fluctuations of the stopping power and sputter yield inherent to the ion–solid interactions. In addition, material contrast from electron-induced secondary electron (eSE) and backscattered electron (BSE) images using scanning electron microscopy (SEM) also shows non-monotonic contrast as a function of Z₂, following the periodic behavior of the stopping power for electron–solid interactions. A comparison of the iSE and eSE results shows similar relative contrast between the metal layers, and not complementary contrast as conventionally understood. These similarities in the contrast behavior can be attributed to similarities in the periodic and non-monotonic function defined by incident particle–solid interaction theory.     

Application of Feature Extraction through Convolution Neural Networks and SVM Classifier for Robust Grading of Apples

This paper proposes a novel grading method of apples,in an automated grading device that uses convolutional neural networks to extract the size,color,texture,an...     

分布动态载荷识别的抗噪处理

针对正交多项式频域法在用多种响应对矩形薄板进行载荷识别中抗噪性较差的问题,综合运用平均法、矩阵预处理和奇异值截断法等方法对之进行改善,并引入空间映射的思想,将该方法的应用范围拓展为复杂的模型.利用仿真算例,证实了该方法具有较好的抗噪性.     

基于MELTAC-N平台的核电厂安全级DCS环网研究与测试

针对工程实践中环网通讯相关问题的处理缺乏理论基础及国产化安全级DCS平台的开发缺乏成熟经验借鉴问题,对基于MELTAC-N平台核电厂安全级DCS环网的软硬件实现进行了研究。提出了安全级DCS环网双环网冗余设计、光切换开关设计等硬件设计方法,以及以RPR协议为基础,采用全数据收发策略的软件设计方法。在CPR1000安全级DCS平台上对安全级DCS环网的可靠性及实时性进行了评价,并进行了容错能力、响应时间及响应时间稳定性测试验证实验。结果表明,基于MELTAC-N平台安全级DCS环网软硬件设计具有较好的容错能力及响应时间稳定性。     

Short-Term Relay Quality Prediction Algorithm Based on Long and Short-Term Memory

The fraction defective of semi-finished products is predicted to optimize the process of relay production lines, by which production quality and productivity ar...     

End-to-End Multiview Gesture Recognition for Autonomous Car Parking System

The use of hand gestures can be the most intuitive human-machine interaction medium.The early approaches for hand gesture recognition used device-based methods....     

The laboratory simulation of abrasive wear

Abrasive wear has long been recognised as one of the most potentially serious tribological problems facing the operators of many types of plant and machinery; several industrial surveys have indicated that wear by abrasion can be responsible for more than 50% of unscheduled machine and plant stoppages. Locating the operating point of a tribological contact in an appropriate operational ‚map’︁ can provide a useful guide to the likely nature and origins of the surface degradation experienced in use, though care must be exercised in choosing the most suitable parameters for the axes of the plot. Laboratory testing of materials and simulations of machine contacts are carried out for a number of purposes; at one level for the very practical aims of ranking candidate materials or surface hardening treatments in order of their wear resistance, or in an attempt to predict wear lives under field conditions. More fundamentally, tests may be aimed at elucidating the essential physical mechanisms of surface damage and loss, with the longer term aim of building an analytical and predictive model of the wear process itself. In many cases, component surface damage is brought about by the ingress of hard, particulate matter into machine bearing or sealing clearances. These may be running dry although, more usually, a lubricant or service fluid is present at the interface. A number of standardised wear test geometries and procedures have been established for both two- and three-body wear situations, and these are briefly described. Although abrasive wear is often modelled as following an ‚Archard’︁ equation (i.e. a linear increase in material loss with both load and time, and an inverse dependence on specimen hardness) both industrial experience and laboratory tests of particularly lubricated contacts show that this is not always the case: increasing the hardness differential in an abrasively contaminated lubricated pair may not always reduce the rate of damage to the harder surface.     

Limits of topographic measurement by the scanning tunnelling and atomic force microscopes

Parameters describing the topographic character of a surface (height, surface wavelength, slope and curvature) can be derived from equivalent sinusoidal profiles. The response of a surface-measuring instrument may be modelled in terms of instrument parameters such as stylus radius, and scanning range and resolution. The performance of the instrument may then be mapped as a zone in amplitude-wavelength (AW) space to show the sinusoidal profiles it is capable of measuring. In a first-order analysis the STM and AFM are considered as equivalent to contact-stylus instruments with a notional stylus radius equal to the tip radius plus the gap. Comparisons between different instruments and types of instrument are readily made by mapping in AW space. The error arising from convolution of the sinusoidal profile with that of the finite tip may be quantified and plotted as contours in AW space.