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1.
对话农机手     
"三夏"时节,田野麦浪滚滚,收割机机声隆隆。小麦2010年又是丰收年,农民们看着丰收景象,满脸洋溢着喜盈盈的笑,农机手们开着联合收割机,满怀着甜蜜的快乐,机欢唱,人开心,同奏着麦收的"欢乐颂"!  相似文献   

2.
王宇 《机电信息》2010,(28):36-37
<正>刚出火车站,天空幽蓝,空气湿润,寻路未果,索一路人,依其指点,穿过条条巷道,眼前便是一望无际的大海了,心情一下子就豁然开朗,长途的疲累此时早已  相似文献   

3.
正在德国的大街上经常可以看到,既有白发老者,又有高挑美女,还有身着蓝色工装的技工,腋下都夹着一本书,目光祥和,举止优雅,慢悠悠行走着,公交车上、一些乘客静静地读书,有时还能见到在等候乘客的片刻,司机也在翻阅书本。自古以来,读书好学的  相似文献   

4.
《现代零部件》2013,(1):5-5
时光如水,岁月如歌。《现代零部件》即将走过悠悠十载春秋,在2013年迎来创刊十周年。十年来,《现代零部件》在广大作者和读者的支持与帮助下,脚踏实地,一步一个脚印,取得了令人欣喜的成绩。回首创刊之初,她犹如一株树苗,在春天萌发嫩芽,沐浴阳光雨露,伴随季节更替,历经重重洗礼,  相似文献   

5.
文中通过运用三轴数控铣床和寻边器,用极坐标编程,对旋切机的凸轮轮廓进行测点,利用MATLAB对所测数据进行处理,找出轨迹方程,利用CAD/CAM软件的公式曲线等工具建模,最终生产出高品质的产品,不但提高了产品的质量,降低了成本,主要为企业找到了反求的捷径.  相似文献   

6.
工程机械发展对液压技术的需求动向   总被引:2,自引:0,他引:2  
进入21世纪以来,世界工程机械发展处于低迷状态,平均增长率有下降趋势,2001年比2000年下降2.2%,自2003年开始,工程机械销售额有一定增长,以日本为例,2003年销售额约100亿美元,比2002年增长15%,其中内需为5247亿日元,增长4%,外需(出口)为6296亿日元,约占总销售额的1/2,增长20%,外需增长主要是中国及亚洲市场需求激增的缘故。由于日本对废气排出量有新的限制,使设备更新量增大,例如,液压挖掘机增长8%,汽车起重机增长12%。据日本建设机械协会预测,2004年日本工程机械将增长9%,达110亿美元,其中液压挖掘机增长16%,小型挖掘机增长6%,由于建设项目…  相似文献   

7.
中国机械工业联合会是为适应国家工业管理体制改革需要,经国务院同意、民政部批准,于2001年4月正式成立的综合性行业协会。按照国家标准委和国家发展改革委的授权,三年多来,特别是在2004年,我们以科学发展观为指导,以市场需求为导向,以为政府、为企业服务为宗旨,本着不“越位”、不“错位”、不“缺位”的工作原则,围绕振兴机械工业,开拓创新,强化服务,  相似文献   

8.
2003~2013时光如水,岁月如歌。《现代零部件》即将走过悠悠十载春秋,在2013年迎来创刊十周年。十年来,《现代零部件》在广大作者和读者的支持与帮助下,脚踏实地,一步一个脚印,取得了令人欣喜的成绩。回首创刊之初,她犹如一株树苗,在春天萌发嫩芽,沐浴阳光雨露,伴随季节更替,历经重重洗礼,一路茁壮成长。而今已有沉甸甸的十岁年轮,并在行业媒体中崭露头角。十年历程,您与我们携手并肩一起走  相似文献   

9.
《橡塑机械时代》2014,(7):30-32
天然橡胶、轮胎、汽车,从上到下,从源头到终端,彼此之间关系紧密,价格上有明显的联动性,在利润上也紧密相关,照常理来讲,天然橡胶价格下跌,轮胎的利润在较短时间上升,影响到汽车,也会令汽车行业受益,反之亦然。  相似文献   

10.
岚县位于山西省西北部,吕梁山北端高寒山区,地处黄河流域中部,属晋西北黄土高原山区.辖3镇9乡,面积1 514 km2,境内多为丘陵区,地势较为平坦,平均海拔1200 m以上,平均气温6.8 ℃,有效积温2 727 ℃,日温差14.7 ℃,年平均降雨为504.9 mm,无霜期为90~125 d.独特的自然条件,既是理想的马铃薯生产区域,又适宜机械化生产.全县粮田面积3万hm2,其中马铃薯每年种植面积均在1万hm2以上.占粮田面积的1/3,是农民收入的重要来源之一.实现马铃薯机械化生产具有得天独厚的优势.  相似文献   

11.
共融机器人重大研究计划研究进展   总被引:2,自引:2,他引:0  
赖一楠  叶鑫  丁汉 《机械工程学报》2021,57(23):1-11,20
“共融机器人基础理论与关键技术研究”重大研究计划,聚焦“刚-柔-软机构的行为顺应与可控性”、“人-机-环境多模态感知与自然交互”以及“机器人群体智能与操作系统架构”三个科学问题,主要面向智能制造、医疗康复、国防安全和学科前沿四个重点方向,实施四年来取得了长足进展,构建机器人与人、机器人与环境、机器人与机器人交互的共融机器人研究体系,推动了工业机器人、服务机器人和特种机器人领域的理论和技术发展,相关科研成果为我国高端制造、康复医疗、国防安全等国家重大需求提供了坚实的理论和技术支撑。对在该重大研究计划支持下所取得的有关共融机器人的主要研究进展进行概述,内容涵盖“与环境共融的加工制造机器人”、“与人共融的康复辅助机器人”、“机器人间共融的群体智能与操作系统”以及“共融机器人前沿:新方法、新原理和新概念”,以此给出后续的重点研究方向和建议。  相似文献   

12.
Semiautomated methods are used to measure elongated, curved and complex branching profiles and isolated perimeter segments in monochrome video images with a general-purpose analysis system. These methods are used to make the major primary measurements of bone histomorphometry. Accuracy and reproducibility of the image acquisition, processing and measurement system is documented by measuring a semicircular standard of known dimensions. Semiautomated applications of the Ar/Le method for measuring areas and perimeters, and calculating lengths and widths of osteoid seams, lengths of mineralization labels and mineral apposition rate, wall width, indirect measurements of eroded, osteoclastic and osteoblastic perimeters without tracing, and measurement of mineralized or total cancellous bone area and perimeter gave values comparable to measurements of the same parameters by tracing or grid counting techniques with equal or better reproducibility and much greater efficiency. Intraindividual variation in measuring multiple bone biopsies was comparable to that reported with current standard methods. Major sources of variability for semiautomated methods were image magnification and selection of profile edges by thresholding, and sources of variability for manual methods are image magnification, numbers of orthogonal intercepts, tracing speed and accuracy of the algorithm used to measure traced pixels. Semiautomated methods are accurate, reproducible and rapid methods suitable for bone histomorphometry.  相似文献   

13.
Aiming at the problem of structure design in reverse-design of mechanism, a structure mapping method based on reverse solving of locus and motion (RSLM) is presented. The mechanism scheme meeting the requirements of geometric and structural features is obtained through RSLM. The element instance subsets related to component are established based on the element type mapping, pair structure type mapping and design knowledge mapping between components and elements layer by layer. The assembly position mapping of elements is established based on the topological structure information of mechanism scheme, and the product modeling of structure mapping is realized. The algorithm program and prototype system of product structure mapping based on RSLM are developed. Application samples show that the method implements the integration of scheme design, assembly design and structure design, and modeling for product structure mapping based on RSLM. The feasibility of assembly is analyzed in scheme design that contributes to reducing the design error, and raising the design efficiency and quality.  相似文献   

14.
This paper reviews the use of copper deactivators and iron corrosion inhibitors in lubricating oils. The auto-oxidation process is described in terms of initiation and chain propagation, branching and termination, and the primary and secondary oxidation inhibitors are described. Copper deactivators and corrosion inhibitors nature and action are discussed, and the paper also examines the applications for these additives.  相似文献   

15.
Researchers worldwide are taking advantage of novel, commercially available, technologies, such as ion mobility mass spectrometry (IM-MS), for metabolomics and lipidomics applications in a variety of fields including life, biomedical, and food sciences. IM-MS provides three main technical advantages over traditional LC-MS workflows. Firstly, in addition to mass, IM-MS allows collision cross-section values to be measured for metabolites and lipids, a physicochemical identifier related to the chemical shape of an analyte that increases the confidence of identification. Second, IM-MS increases peak capacity and the signal-to-noise, improving fingerprinting as well as quantification, and better defining the spatial localization of metabolites and lipids in biological and food samples. Third, IM-MS can be coupled with various fragmentation modes, adding new tools to improve structural characterization and molecular annotation. Here, we review the state-of-the-art in IM-MS technologies and approaches utilized to support metabolomics and lipidomics applications and we assess the challenges and opportunities in this growing field.  相似文献   

16.
TQM与ERP的集成策略探讨   总被引:2,自引:0,他引:2  
针对TQM与ERP在企业中应用独立的状况,从TQM与ERP的发展背景和特点出发,阐述了两者所具有的内在协调性和互补性关系,从理论、技术、方法与工具等层面上分析了TQM与ERP集成的可行性与必要性,从文化整合、过程整合、技术整合和分步实施等方面探讨了TQM与ERP的集成策略和实施方案。TQM与ERP的有机集成,可以充分有效地整合企业的资源,快速响应市场,提高企业的市场竞争力。  相似文献   

17.
To support and serve engineering design, creative design based on knowledge management is proposed. The key knowledge factors of creative design are analyzed and discussed, and knowledge extraction tools are utilized to distill the important knowledge to serve for knowledge resource of creative design. The implementation of creative design mode is described and executed, which can promote the intelligent asset of the enterprise and shorten the period of creative design. With this study, design afflatus and conceptual design can be achieved expediently and effectively.  相似文献   

18.
在Cu-Sn-P系基体中添加不同量的合金元素N i和Fe,采用粉末冶金方法制备烧结轴承材料,通过对比研究了N i和Fe对其性能的影响规律。结果表明,N i和Fe元素都可以提高材料的表观硬度和压溃强度,改善材料的摩擦磨损性能,但N i元素对压溃强度的提高更为显著。Cu-Sn-P基体中添加N i和Fe含量不宜过高,分别以2%和4%为宜。  相似文献   

19.
45钢电子束扫描相变硬化组织和硬度的研究   总被引:4,自引:0,他引:4  
电子束表面处理可以提高钢铁材料的表面硬度和力学性能。研究电子束扫描对45钢硬化层组织和性能的影响,探讨电子束功率、扫描速度等工艺参数对硬化层组织和性能的影响。采用扫描电镜分析45钢电子束表面强化层的显微组织,用显微硬度计进行硬度测试。结果表明,45钢经电子束扫描处理后,硬化层的组织为针状和板条状马氏体,组织比常规调质处理更加均匀、细小,试样表面的平均硬度达58 HRC,比淬火加低温回火处理的硬度高3~5 HRC,是调质处理的两倍,从处理表面往下沿深度方向硬度逐渐减小。电子束工艺参数对硬化层组织和性能有较大影响,硬化层宽度和深度随着电子束功率的增加而增加,随着扫描速度的增加而减小;硬化层的最高硬度随着电子束功率密度的增加而增加,随着扫描速度的增加而减小。  相似文献   

20.
Nanoimprint lithography (NIL) is recognized as one of the most promising candidates for the next generation lithography (NGL) to obtain sub-100 nm patterns because of its simplicity, high-throughput and low-cost. While substantial effort has been expending on NIL for producing smaller and smaller feature sizes, considerably less effort has been devoted to the equally important issue—alignment between template and substrate. A homemade prototype nanoimprint lithography tool with a high precision automatic alignment system based on Moiré signals is presented. Coarse and fine pitch gratings are adopted to produce Moiré signals to control macro and micro actuators and enable the substrate to move towards the desired position automatically. Linear motors with 300 mm travel range and 1 μm step resolution are used as macro actuators, and piezoelectric translators with 50 μm travel range and 1 nm step resolution are used as micro actuators. In addition, the prototype provides one translation (z displacement) and two tilting motion(α and β ) to automatically bring uniform intact contact between the template and substrate surfaces by using a flexure stage. As a result, 10 μm coarse alignment accuracy and 20 nm fine alignment accuracy can be achieved. Finally, some results of nanostructures and micro devices such as nanoscale trenches and holes, gratings and microlens array fabricated using the prototype tool are presented, and hot embossing lithography, one typical NIL technology, are depicted by taking nanoscale gratings fabrication as an example.  相似文献   

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