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1.
本文主要分析了我国目前数控机械产品的研发的状况;并且有针对性的提出了关于我国数控机械产品的开发的方向和研制的路线和技术问题;提出了具体的对数控机械设备的进行开发的内容和策略;并且提出了在引进国外先进的技术的数控技术的同时,用该开发出具有我国特色的数控机械的产品,并且指明了数控机械产品的发展的大方向;并提出了我国数控机械产品的售后服务的模式。本文主要是针对数控土木机械的发展方向进行讨论的。  相似文献   

2.
张驰 《中国机械》2014,(10):192-192
随着时代的进步和高速的发展,各国的能源问题也被逐渐的提上日程。本文就世界能源的现状还有内燃机的发展进行相应的论述,提出相应的看法和亟待解决的措施。对中国的能源发展提出相应的看法,希望能走出一个适合中国国情的一条特色的道路。  相似文献   

3.
面向工程的优化算法性能实验研究   总被引:1,自引:1,他引:1       下载免费PDF全文
韩明红  邓家禔 《中国机械工程》2007,18(12):1460-1464
针对10种工程常用的优化算法进行实验研究,选取12个优化算法Benchmark测试函数进行算法评价,包括连续的和不连续的、凸的和非凸的、单峰的和多峰的、二次的和非二次的、低维的和高维的、有约束的和无约束的测试函数。对实验结果进行分析,从解空间的角度对算法的特性进行分析总结,给出了算法选取的准则。  相似文献   

4.
在现在的发展中,各项工作都需要在先进的科学技术的支持下更好的开展相关的工作计量质量检验检测工作的进行对我们的工作有很大的帮助,面向未来,就要求我们在先进的技术的指导下更好的开展相关的工作。我们自身的发展还不够完善,根据实际的发展需求不断地做好相关的工作,这样才能达到更高的发展水平,随着现代化进程的加快,我们就更需要做好自己的工作,达到发展的目标。  相似文献   

5.
锅炉在工业生产还有日常生活中有着重要的作用,现阶段我国的锅炉的使用的效率,还有非常大的改进空间。因此对于锅炉进行检验还有对于锅炉的能量的消耗进行分析对于提高锅炉的使用的效率热能产生的效率的提升都有重要的作用。  相似文献   

6.
随着时代的发展,经济的增长,社会的进步,我国的综合国力逐渐提高,科学技术不断的改良、创新、进步,而这些改变随之而来的是我国的工业发展越来越迅速,以往的封建的旧的思想以及旧的技术、产品已近满足不了这个时代的需求,人们的生活水平不断提高,对于新兴的产品以及技术的需求越来越高,超声振动辅助钻削钛合金技术的发展就是其中之一。  相似文献   

7.
随着科技的进步,人们的出行方式产生了巨大的变化,汽车的普及在给人们的出行提供前所未有的便捷的同时,其产生的污染也是十分严重的,汽车发动机所造成的污染问题不仅减低了环境质量,同时对人们的身体健康也造成了威胁。基于此,本文针对机动车中的微型汽车进行相应的发动机尾气污染排放的研究,指出污染物的危害,并针对性的提出相应的治理措施。  相似文献   

8.
从古至今,我国的农业取得很大的发展,已基本实现自动化,作为其中最重要的经济作物之一的玉米,在其中的地位非常重要。玉米在一定程度上不但为我国的经济发展做出了相应的贡献,另外在人们的日常饮食以及生产当中的作用也十分巨大,因此将玉米高产栽培技术的推广工作做好具有非常深远的意义。然而通过对广大玉米产地进行的实际调查研究发现,在具体的推广高产栽培技术的的时候,依然有许多问题对提高玉米的生产效益造成了很大的困扰。下面我们就将对此进行简单的分析,并有针对性的提出相应的解决措施,希望能够对我国农业的发展起到借鉴和参考的作用。  相似文献   

9.
提出了一种将模糊控制、滑模控制与自适应控制三者有机的整合的模糊滑模自适应控制的算法,并以虚拟轴机床的单通道的阀控非对称液压缸作为研究的对象。仿真实验表明,该算法可以使得系统输出渐进地收敛于参考的输入信号,且可以很快地对变化的信号进行有效地跟踪,对参数的摄动与有界的干扰具有不变性。提出的方法与传统的PID控制比较,更加的适用于较强的干扰的复杂系统、高阶的非线性,将方法应用于虚拟轴机床的液压的控制系统可以获得较高的控制精度、较好的机床动态性能与较小的稳态误差。  相似文献   

10.
预应力混凝土管桩的生产过程,其中预应力是对管桩抗弯性能的一个最重要的参数,预应力的施加是由一台张拉机的设备来控制,以前采用传统的标尺来控制管桩长度的拉伸量,员工观看标尺刻度到达规定的标准值时,人手控制停止的方式来决定一条管桩的预应力,这样对操作员工的要求较高(不同管桩的长度的拉伸值要相应的改变),控制产品的精度差,产品的质量得不到保证。针对生产现场的实际情况,合理设计张拉机的全自动控制系统,对员工操作的要求降低,全自动控制系统精度得到保证,从而保证产品质量的稳定,提高公司的生产效益。  相似文献   

11.
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...  相似文献   

12.
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.  相似文献   

13.
Giannuzzi LA  Utlaut M 《Ultramicroscopy》2011,111(11):1564-1573
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.  相似文献   

14.
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...  相似文献   

15.
分布动态载荷识别的抗噪处理   总被引:2,自引:2,他引:0  
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.  相似文献   

16.
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。  相似文献   

17.
The fraction defective of semi-finished products is predicted to optimize the process of relay production lines, by which production quality and productivity ar...  相似文献   

18.
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....  相似文献   

19.
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.  相似文献   

20.
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.  相似文献   

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