模糊机械科学与技术：21世纪机械科学的重要发展方向

阐述了模糊技术在产业上的现实意义，提出了模糊机械科学与技术这一新思想，并对模糊机械科学与技术的立论依据、理论体系进行了初步阐述，最后提出了我国发展模糊机械科学与技术的策略。     

机械电子技术的发展及其对产业的影响

机械电子学(mechatronics)自从20世纪70年代初正式问世以来,已经30多年了?它以其固有的两个特点,在新世纪飞速发展。这两个特点是：     

论机械学

对于“机械学”这一个广泛使用的名称的来源、各种使用中所具有的内涵及其变迁进行了考察,认为不应当仅仅由行政管理上的划分来定位机械学。在分析我国对机械科学、机械工程和机械学习惯上的理解和它们之间应有的相互关系之后,建议把机械学定位在机械科学的基础部分,而机械工程则是机械科学的应用技术部分。分析了机械发展的历程特别是对未来的进行了探讨。认为人们在追求手足延长的时候,期望得到一种“有头脑”的手足的延长将是引导机械发展的主导因素。据此,对于机械科学、特别是机械学应当如何使自己适应机械的发展,即如何拓展和更新自己的内容提出了看法。     

微机械元件和仪器的新进展

微机械元件和微机械仪器，适于大批量生产，具有成本低廉、性能优良和体积微小及集成高度的特点。近十年来，在研制、开发及市场扩大方面取得了巨大的进展，展现了美好的前景。     

多晶硅微机械零件的制作及测试

探讨利用硅表面微细加工工艺制造微型机械的方法，制作了微涡轮，微传动齿轮，微螺旋弹簧和微凸轮传动机构等微机械结构，实现了齿轮的啮合传动，微弹簧扭转及微凸轮传动机构的运动。对多晶硅材料的机械物理性能，微机械系统动力学特性进行了测试分析。     

平面凸轮引导机械的型综合

迄今为止，凸轮引导机构型综合研究的报导不多。本文着重对单自由度三构件、四构件和五构件凸轮引导机构进行了型综合，并探讨了其引导特点，从而为选择合适型的凸轮引导机构提供帮助。     

提高煤矿机械安全状况的探讨

由于科技的进步，现代煤矿的开采也运用了机械化，但是我国的煤矿安全生产管理相对落后与发达国家，安全的状况不容乐观。在煤矿企业的生产中，煤矿机械设备的安全性起到了很重要的地位，它直接关系到安全生产。本文研究和分析了煤矿机械的安全现状，并有针对性的提出了改进措施。     

无线通信系统中的微尺度射频元件

射频元件微型化是微型无线通信系统发展的关键所在.本文从微机械开关、微机械谐振器、微机械滤波器、微机械天线、微机械电感及电容等多方面,介绍微尺度射频元件的研究和应用现状,并对其发展前景作了展望.     

水稻机械发展已到攻坚阶段

我国是农业大国,解决好"三农"问题是实现小康社会的关键。农村经济建设的加速和农村种植结构的调整过程中,农用工程机械起到了强有力的作用。中央把"三农"问题作为全党工作的重中之重,采用很多措施加强农业基础设施建设,并投入大量资金对农民购置农业机械进行补贴,农业建设快速发展,为这类产品应用提供了极为广阔的发展空间。近年来,国内小型农用工程机械市场增长量尤其迅速,产销量渐趋火爆,发展前景广阔。也成为机床工具行业瞩目的市场份额,本期推出以"农用机械制造"为主题的专题报道,共同探讨现代化制造设备与技术如何装备现代化农业。     

公路工程施工机械选择与配套方法探讨

在分析阐述公路工程机械设备选择和配套应遵循主要原则的基础上，探讨了机械设备选择的方法以及存在的问题与对策，论述了施工机械与工量的关系与配置，研究成果为公路工程机械化施工提供参考。     

叶切面最大厚度的数值计算方法

叶切面最大厚度计算是螺旋曲面加工准备过程中必要的环节.探讨适合于叶切面最大厚度的数值计算方法.详细介绍叶切面厚度数值计算所包括的叶切面最大厚度区域搜索、叶切面最大厚度精确计算过程.     

电涡流传感器互换性的研究

本文介绍了电涡流传感器互换性的概念及提高互换性的思路和方法,强调了工艺这一关键因素。这些对其它类型的传感器同样有着一定的指导意义。     

Geometrical method of selection of features of diagnostic signals

The paper presents the method of selection of features of diagnostic signals relying on the geometry of observation space. The method presented here uses two criteria of ability to separate (isolate) classes of an object's state: the criterion of average scatters and the original criterion of number of prototypes of classes. The method can be successfully used for initial analysis of input data to a neural network dealing with recognition of patterns and classification of an object's state. It also possible to use the algorithm presented here for determining the prototypes of classes needed for creating the training set for the neural network.     

机械基础虚拟实验室的开发及应用

简要介绍了虚拟实验室在国内外的研究现状,分析了机械基础虚拟实验室的基本要求,探讨了利用仿真技术对机械基础虚拟实验室的开发过程,以组合机构为例介绍了机械基础虚拟实验室的应用。     

Natural frequencies of vibration of a class of solids composed of layers of isotropic materials

In a recent paper, the Ritz method with simple algebraic polynomials as trial functions was used to obtain an eigenvalue equation for the free vibration of a class of homogeneous solids with cavities. The method presented is here extended to the study of a class of non-homogeneous solids, in which each solid is composed of a number of isotropic layers with different material properties. The Cartesian coordinate system is used to describe the geometry of the solid which is modelled by means of a segment bounded by the yz, zx and xy orthogonal coordinate planes and by two curved surfaces which are defined by fairly general polynomial expressions in the coordinates x, y and z. The surface representing the interface between two material layers in the solid is also described by a polynomial expression in the coordinates x, y and z. In order to demonstrate the accuracy of the approach, natural frequencies are given for both a two- and three-layered spherical shell and for a homogeneous hollow cylinder, as computed using the present approach, and are compared with those obtained using an exact solution. Results are then given for a number of two- and three-layered cylinders and, to demonstrate the versatility of the approach, natural frequencies are given for a five-layered cantilevered beam with a central circular hole as well as for a number of composite solids of more general shape.     

Relation between the amplitude of acoustic emission of an ensemble of microflaws and the deformation rate: Reconstruction of the number of AE events during a change in the dynamic range of detected signals

A model of acoustic emission from a dislocation cluster during its passage through a boundary is considered. A dependence of the amplitude of an acoustic-emission (AE) event on the deformation rate and the loading frequency has been obtained. Algorithms for reconstructing the number of lost AE events below the discrimination threshold of the instrumentation are obtained for the case of a power-law amplitude distribution. A method for correcting the parameters of the detected stream of events at various discrimination thresholds, deformation rates, and loading frequencies is described. A method for estimating the dynamic range on the basis of the average value of the detected AE-signal amplitudes is proposed. We propose using the results of this study for increasing the reliability of the AE method for diagnostics of a prebreakdown state.     

膨胀套导向机构的设计

通过分析膨胀套在实际使用产生滑移受阻现象、卡死现象原因的实质,并在分析产生问题原因的基础上提出了改进措施即：增加导向机构。     

A method for improving the accuracy of evaluating the dimensions of flaws in walls of tubular elements of structures

An algorithm for evaluating the real accuracy of the basic measuring instrument (exterior or in-tube flaw detector) in measuring parameters of flaws of a particular inspected tube was proposed on condition that the basic measuring equipment has no systematic error, while a verification instrument is considered as “absolutely” precise or “reference.” A statistical method of increasing the accuracy of evaluating the dimensions of flaws in thin-walled tube elements was developed on the basis of a correlation between the dimensions of flaw parameters. It can be taken as a basis for finding real values of parameters of flaws and for performing reliable calculations of the residual strength and residual life, for scheduling optimal periods for the next inspection of pipelines, and for ranging segments of a pipeline by a risk criterion, thus providing optimal scheduling of repairs.     

飞行器上设备软件在线升级方案设计与应用

为解决飞行器上各个设备软件升级困难问题,以飞行器上已有的通信接口为基础,设计了一套成本低、通用性好、可靠性高的飞行器上设备软件在线升级方案。试验结果表明,该方案简单可靠,可用于飞行器嵌入式设备软件的在线升级与维护,具有较好的应用前景。     

飞行汽车双横臂悬架自由度计算分析

传统空间机构自由度计算多而且复杂,对于具体的计算有很多限制,不适合用来研究空间机构的运动。以飞行汽车悬架为研究对象,对空间自由度计算公式进行了分析,为悬架空间设计计算提供了依据。