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1.
本文以A319/320滑轨肋零件为例,根据该零件结构特点,介绍了典型肋板类零件如何确定工艺方案及关键尺寸控制方法。  相似文献   

2.
武艳军  许波  张宏武 《考试周刊》2014,(43):137-138
杯盖零件板料薄,需要多种工序进行冲压,应根据该零件的结构特点,围绕如何提高生产效率、降低制造成本、简化模具结构,制订复合模冲压成形的工艺方案。本文通过对零件进行工艺分析,设计出了用于成形盖杯零件的冲压模具,阐述了挤边、冲孔、拉深复合模的过程及工作过程。该模具能保证零件质量,具有结构简单、操作安全方便、生产效率高等特点。  相似文献   

3.
《考试周刊》2016,(4):193-194
本文分析了薄壁零件的几何特点,提出了利用有限元和数控补偿提高薄壁零件加工精度的思想,分析了利用有限元建立零件几何模型、材料模型、受力模型、载荷施加、网格划分、变形分析的基本过程。  相似文献   

4.
盘套零件工艺夹具的改进   总被引:1,自引:0,他引:1  
通过零件特点的分析,改进了大批量生产盘套零件的工艺与夹具,并对改进前后的夹具设计、加工效率和加工精度进行了全面的比较,阐明了改进后工艺夹具的优势,从而保证了零件的加工精度要求,提高了加工效率。  相似文献   

5.
文章介绍了宏程序的特点,之后分析了曲面轴零件的加工要求,确定了曲面轴零件加工方法,选择了加工所有刀具,安排了加工工序,并应用宏程序编写了数控加工程序,结果表明将宏程序应用在曲面轴零件编程中,大大简化程序,提高编程效率。  相似文献   

6.
介绍了模具及其零件在制造过程中对周期与成本要求的特点,分析了快速成型技术制造模具零件的实现方法与优越性,并以制件充电器盒为例说明了该工艺的具体应用,对其他制件的模具零件快速成型制造具有一定的参考价值.  相似文献   

7.
波浪形连接端子的多工位级进模设计   总被引:1,自引:0,他引:1  
分析了波浪形连接端子零件的冲压成形工艺。介绍了零件成形所需的冲小圆孔、冲异形孔、冲方形孔、切边、打筋、打字、打凸、倒角、竖舌、压舌和成形等17工位的排样设计,以及模具结构特点和关键成形零件的设计;根据端子中间连接部位在u形弯曲时产品步距将会缩小的特点,着重讨论了利用斜楔块弯曲成形U形结构的方法。  相似文献   

8.
本文叙述了通过教学改革创新,激发学生的学习兴趣,注重学生对零件模型的分析,设计科学合理的教学内容。根据专业特点,培养学生对零件设计的严谨性和创造性,真正做到学以致用。  相似文献   

9.
文章分析了插件端子成形的工艺特点,介绍了冲压该零件的工位排样设计和模具结构设计要点,模具结构中主要工作机构的设计要点,以及凸模、凹模等主要零件的加工工艺。  相似文献   

10.
目前很多细长杆类零件多是借助普通车床完成的,若我们要用数控车床轻松地加工出细长杆类零件,就必须探索出数控加工工艺的创新性技巧并突破传统的数控加工工艺规范。本文首先论述了数控车床细长杆类零件的加工的特点,继而探索其加工技巧。  相似文献   

11.
高校文化的内部功能有:(1)影响成员意识和规范成员行为,(2)增强学校凝聚力,(3)调节学校内部的社会关系;外部功能有:(1)利用组织意识指导学校与环境互动,(2)利用高校文化特征树立学校形象,(3)利用特定的高校文化适应环境。高校文化的内容包括:意识体系,制度性规范,行为基本模式,象征性符号和模范人物故事和传说等。高校文化的主要特征应与各校特有专业相联系。高校文化内部传播的目的是维持学校内部统一、实现整体协调和整体运作;外部传播的目的是突出本校的文化个性,给公众留下深刻的识别印象,扩大本校对,公众的影响力。  相似文献   

12.
试析大清律中例的地位和作用   总被引:1,自引:0,他引:1  
清代律例合编的法典编纂形式和“有例不用律”的明确规定,使得清例的法律地位大大提高、律的法律地位大为降低。律例合编一度协调了律例矛盾,例对于律的补充、修改、废止作用也曾适应了统治的需要。但是,由于例多为一人一事而设,为贪官污吏徇私枉法留下了很大的空间,导致吏治腐败,加速了清朝的灭亡。  相似文献   

13.
What should be learned? How should it be organized for teaching? These seemingly simple questions are deceivingly political. Curriculum theorists are preoccupied with the politics of the first question at the expense of the realpolitik of the second. Instructional designers are preoccupied with the realpolitik of the second question at the expense of the politics of the first. I argue that conceptual distances between curriculum theory and instructional design are based on divisions of labour established during the 1960s. After decades of neglect, curriculum theorists, and specifically critical theorists, appear clueless when it comes to curriculum design and the realpolitik of their causes. When it comes to the realpolitik of practice their political causes are formless. Quite the opposite of critical theorists, instructional theorists nearly mastered the realpolitik of form but have no political causes. I argue that, to contradict the status quo of C&;I, curriculum theorists will have to dirty their hands with the realpolitik of form and instructional designers will have to clutter their heads with theory.  相似文献   

14.
文明是劳动的积累和积累的劳动,是人类智慧和汗水的结晶,是人们开创新的历史的既得力量。人类社会的进步取决于人类文明的历史传承与创造,社会个体的价值寓于个体自身在历史发展过程中对人类文明的传承与创造。历史的实现方式在于人们对人类文明的历史传承与创造。英雄人物在历史中的作用取决于其是否融入创造历史的群众运动中去。人类文明的传承与创造是人类历史走向进步的重要基石,也是人类历史得以延续与发展的社会基因。人类文明的历史传承与创造积淀成历史的现实与现实的历史,人类历史的演进与人类文明的传承与创造齐头并进。  相似文献   

15.
It is known by entropy theory that image is a source correlated with a certain characteristic of probability. The entropy rate of the source and ? entropy (rate-distortion function theory) are the information content to identify the characteristics of video images, and hence are essentially related with video image compression. They are fundamental theories of great significance to image compression, though impossible to be directly turned into a compression method. Based on the entropy theory and the image compression theory, by the application of the rate-distortion feature mathematical model and Lagrange multipliers to some theoretical problems in the H.264 standard, this paper presents a new the algorithm model of coding rate-distortion. This model is introduced into complete test on the capability of the test model of JM61e (JUT Test Model). The result shows that the speed of coding increases without significant reduction of the rate-distortion performance of the coder.  相似文献   

16.
全球化是一个以科学技术的进步为基础、以资本的国际流动和世界市场体系的构建为表征的复杂运动。全球化过程客观上蕴涵着一种世界性全方位整合取向。然而,这种一体化运动却遭到了民族国家这种政治结构形式的抵制。因此,全球化过程中的政治文化呈现为明显的民族性碎裂状态。其原因不仅在于政治文化的民族性,同时还在于各种政治体利益的特殊性。全球化进程的不断展开客观上要求把政治文化的民族性置于全球性政治共识的基础上,从而形成一种以全球性共识为基础的多元政治文化格局。  相似文献   

17.
选取“文选学”成立过程当中的关键文学史实作为案例切入,通过系统地分析,如实勾划出六朝隋唐时代文学观念演进的各主要阶段,特别提出中古审美视角转变的三个环节,从而反向论证《文选》和“文选学”正是中古文学观念主要特质的代表。进而将之放在近三百年学术史的坐标上同其它专学的发展作以对比,阐明其美学思想在中国文学史的演进过程中所起的再度深化作用。并在探讨后一子命题的同时,联系传统文献的分类思想,对之进行类型学层面的学术阐释。  相似文献   

18.
介绍了论文提交系统的开发背景、设计和实现的过程.在系统设计部分主要介绍了论文提交的主要流程、功能结构、各级用户及其角色的定义、系统的功能以及后台数据库的设计.在实现部分,主要说明系统的开发环境和开发工具,并给出主要模块的代码.  相似文献   

19.
诗歌意象的组合是诗歌话语的组织。从语言学角度对意象跳跃的成因、定义、存在基础及功能进行分析,诗歌意象出现跳跃是由于话语中缺失某些信息因素之间的确定与被确定关系,而使语义间连贯与衔接的正常状态被破坏而造成,它以话语的语用含义作为它在诗歌中存在的基础,能够起到丰富话语意义的作用。  相似文献   

20.
This paper discusses the most persistent controversial issue that occurred in Western educational philosophy ever since Socrates questioned the Sophists: the role of truth in teaching. Ways of teaching these kinds of controversy issues are briefly considered to isolate their epistemic characteristics, which will enable the interpretation of Plato and Dewey as exemplars of rationalism and empiricism regarding the role of knowledge in the curriculum and thus include their partial truths in the epistemic ethos of teaching. The consideration of pedagogy will then include the partial truths of rationalism and empiricism in the epistemic ethos of teaching by following Kant's 'Concepts without percepts are empty; perceptions without conceptions are blind'.
This claim, however, is narrowed down in two ways compatible with postmodernism and the heavy emphasis on constructionism in faculties of education. After quoting Harry Broudy's statement that the educational epistemic ethos should be domain-specific, guided by the experts' inquiry protocols in each curricular area, it is narrowed down further with Maxine Greene's explication that it should be pluralistic and lesson-specific. This epistemic ethos is not argued as a synthesis but as an aggregate of the partial truths of various epistemologies in the spirit of the postmodern doubt in any one theory of knowledge without throwing out the baby with the dirty bath water.
Finally, the streams of consciousness involved in teaching and learning good knowledge are described phenomenologically to disclose how truth can be disclosed in teaching, thereby grounding propositional knowledge, for example, ontologically in the being of the student and in the being of the world.  相似文献   

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