首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 93 毫秒
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.
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   

10.
殷东岳  孔栋  王晨 《中国机械》2014,(17):144-145
在基建矿井的设备管理当中,很好的针对设备的实际状况,并且进行相应的改进以及技术方面的提升,对于维持企业的经济效益、不断的增强企业的竞争力来讲,有着积极的作业和意义。文章将针对这一方面的内容展开论述,详细的分析如何改进设备管理之中存在的问题和不足,并且提出相应的措施方案,力求加强实际当中的操作和应用,更好的为相关工作的进行作出积极贡献。  相似文献   

11.
The effect of the prebuckling in-plane deformations on the elastic flexural-torsional buckling of laterally fixed circular arches is studied in this paper. The finite strains and the energy equation for the flexural-torsional buckling of arches have been derived based on an accurate orthogonal rotation matrix. A closed form solution for the elastic flexural-torsional buckling resistance of laterally fixed arches in uniform bending, including the effects of the prebuckling deformations, is obtained. It is found that the notion that the prebuckling deformations increase the flexural-torsional buckling moment of an arch or of a beam is not necessarily correct for a laterally fixed arch or beam in uniform bending, in deference to a laterally pinned arch. When a laterally fixed arch is subjected to positive uniform bending, the effects of the prebuckling deformations decrease the buckling moment, and the reduction of the buckling moment increases with an increase of the included angle and of the out-of-plane slenderness ratio of the arch. When a laterally fixed arch is subjected to negative uniform bending, the effects of the prebuckling deformations decrease the absolute value of its buckling moment when the included angle is very small, but increase the absolute value of the buckling moment when the included angle exceeds a certain value. The increase in the absolute value of the buckling moment increases with an increase of the included angle and of the out-of-plane slenderness ratio of the arch. When the ratio of the out-of-plane to the in-plane second moments of area of the cross-section is not small, both the reduction of the buckling moment of a laterally fixed arch in positive uniform bending and the increase of the buckling moment of a laterally fixed arch in negative uniform bending, are substantial.  相似文献   

12.
轿车门系统结构设计与优化是整车开发过程中的重要环节。车门的强度直接关系到整车在冲击、碰撞等载荷下的安全问题,车门结构静态强度的计算分析,在车门结构设计进程中非常重要。文中首先简要介绍了静态强度所涉及到的非线性有限元的基本理论,然后以某中高级轿车前车门为例,利用计算机辅助分析车门的静态强度,考虑变形的非线性因素,通过对车门的非线性有限元求解来分析车门强度,由计算所得到的车门强度性能指标来指导车门的结构设计。  相似文献   

13.
Aiming at providing with high-load capability in active vibration control of large-scale rotor system, a new type of active actuator to simultaneously reduce the dangers of low frequency flexural and torsional vibrations is designed. The actuator employs electro-hydraulic system and can provide a high and circumferential load. To initialize new research, the characteristics of various kinds of active actuators to control rotor shaft vibration are briefly introduced. The purpose of this paper is to introduce the preliminary results via presenting the structure, functions and operating principles, in particular, the working process of the electro-hydraulic system of the new actuator which includes a set of high speed electromagnetic valves and a series of sloping cone-shaped openings, and presenting the transmission relationships among the control parameters from control signals into the valves to active load onto shaft. The course of the work is dynamic, and a series of spatial forces and moments are put on the shaft to get an external resultant force to reduce excitations that induce vibration of shafts. By checking states of vibration, the actuator can control the impulse width and the interval of injection time for applying different control force to a vibration shaft in two circumference directions through the regulating action of a set of combination directional control valves. The results from simulating analysis and experiment show evidence of that this design can satisfy the case of active process of decreasing of flexural and torsional vibrations.  相似文献   

14.
During plastic process,the material flow is strongly influenced by the contact area between deformed workpiece and die.In rolling process,difference of roll diameter makes the contact area between roll and deformed tape different,which leads to different material flow and the distribution of powder density.A numerical modelling of the first rolling process for 61-filament high temperature superconducting tape is constructed and the influences of roll diameters on deformation behavior of the tape are discussed.It can be found that the BiSrCaCuO(BSCCO)powder in the center of the tape has higher relative density than those in the periphery of the tape during rolling process.With the increase of roll diameter,the length of the contact arc in the roll gap expands which lead to the in- creasing of transversal strain and the decreasing of the related longitudinal strain.It makes the value of longitudinal strain ratio decrease gradually,which decreases the possibility of occurrence of the transversal shear band,simultaneously it increases the risk of occurrence of longitudinal crack.  相似文献   

15.
基于生物质谱的蛋白质组学绝对定量方法研究进展   总被引:1,自引:0,他引:1  
曹冬  张养军  钱小红 《质谱学报》2008,29(3):185-191
蛋白质组学定量方法包括相对定量和绝对定量两部分。相对定量蛋白质组学(也称比较蛋白质组学)是指对不同生理病理状态下细胞、组织或体液蛋白质表达量的相对变化进行比较分析;绝对定量蛋白质组学是测定细胞、组织或体液蛋白质组中每种蛋白质的绝对量或浓度。目前蛋白质组学的绝对定量方法主要有基于内标法的蛋白质组学绝对定量方法和基于质谱数据统计分析的非标记方法。蛋白质组学定量的信息可以帮助了解蛋白质在相互作用网络中所起的作用;通过对临床生物标记物绝对量的分析,可以帮助直观地判断疾病的发生和发展过程,这对于临床诊断和疾病治疗都具有现实的指导意义。  相似文献   

16.
利用可见光谱数字化分析系统将铝合金中Fe元素Fe526.95nm分析谱线组谱图转变为数字化的电子谱图,使用计算机自动分析代替人眼视觉判断,解决谱图的量化分析和记录难题。对4种不同Fe元素含量的铝合金样品进行数字化分析测定,探索选用Fe526.95nm谱线作为分析谱线,选用Cu529.25nm谱线作为比较谱线进行定量测定的方法,数据显示分析谱线和比较谱线的强度比值与Fe元素含量成正比关系。研究数字化系统指导视场定位和谱线辨别的途径,降低可见光谱分析的技术难度并提高快速分析的可靠性。结果表明,数字化技术保持快速分析特点的同时可以达到定量分析目的,能够有效解决铝合金中Fe元素的快速定量分析及材料牌号鉴别问题。  相似文献   

17.
Observation of raindrop size distribution( DSD) with a vertically pointing micro rain radar( MRR) has important significance in the precipitation measurement field. The Mie scattering of large particle,vertical wind and air turbulence have great influences on the retrieval of DSD measured by MRR. This paper simulates the process of how three factors affect the inversion of DSD and the calculation of other precipitation parameters,then makes the errors analysis. Because the wavelength of MRR is 12.5mm,M ie theory is more suitable for the precipitation particle than Rayleigh approximation,w hich may cause the underestimation of number density of small droplets and the overestimation of that in middle field. The vertical wind results in inaccurate estimation of particle terminal velocity,so the diameter is measured with some errors by empirical relationship,w hich affects the calculating accuracy of radar reflectivity and rain rate. Air turbulence can broaden the pow er spectral density,of which the impact on the inversion of DSD are concentrated in small droplets field. Then the measured data from MRR is analyzed and the results prove the impacts of those factors. Finally,according to the analysis and application limits,the prospect of the future research trend of particle size distribution is conducted.  相似文献   

18.
A graph as the new engineering method for estimate the safety of bulging deformation of coke tower is proposed. Through stresses analysis of circumferential weld of coke tower and comparing the stresses produced by pressure with heat stress of steady state, residual stress, bending stress produced by both itself weight and wind loads, it showed that the stresses produced by pressure on the angle distortion are the main factor of equivalent stress of the combined stress. After comparing four kinds of stress controlling conditions, the relation to stress with depth of angular distortion, grade of curvature of angular distortion and half of region of angular distortion has been inferred. Graph of deformation allowable value of coke tower for different condition by angular distortion and half of region of angular distortion has been plotted. The five steps for its engineering use have been explained. The lighter the grade of curvature is, the larger of bulge allowance, may be, and the bigger of depth of angular distortion may pose too. For the coke tower with a popular structure of Dg 5 400 mm×28 mm, the result by graph is nearly more than the result of two formulas formed by other research, the error is less than 7.0%. But, the graph can be easily applied to different size of angular distortion.  相似文献   

19.
以德士古气化炉耐火砖的内壁蚀损检测设备为基础,对采集到的点云数据做了进一步处理.通过对数据的筛选和剔除,实现了数据点的平滑降噪细化和精简.然后利用点云对整、网格划分和分色显示等方法,最终完成了内壁腐蚀情况的三维建模.重点讨论了点云数据的预处理及后处理的方法,并根据内壁耐火砖的腐蚀阈值,提出了一种气化炉内壁腐蚀区域的识别与分割方法.对耐火砖的腐蚀分析、气化炉的生产与维修提供了可靠依据,并在工程应用中获得了一致认可.  相似文献   

20.
The effect of the molecular structure of basic nitrogen compounds on the lubricating properties of sulphurised olefin has been investigated using a Timken tester. X-ray Photoelectron Spectroscopy (XPS) and Energy Dispersive X-ray Analysis (EDAX) were used to study the chemical states of sulphur and nitrogen on the rubbed surfaces and the reaction rates of sulphur and iron separately. It was found that the antiwear and friction reduction properties of sulphurised olefin are greatly influenced by the different molecular structures of the basic nitrogen compounds. A composite additive package containing basic nitrogen compounds with sulphurised olefin can produce either synergistic or antagonistic effects, due to the influence of the different molecular structures of the basic nitrogen compounds. XPS analysis revealed that a tribochemical protective film containing nitrogen and sulphur was formed on the rubbed surface. EDAX analysis indicated that the reaction rates between elemental sulphur and iron were influenced by the different molecular structures of the basic nitrogen compounds. It was found that the apparent reaction rates of elemental sulphur and iron are related to the tribological characteristics of the additive package.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号