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1.
钳工实习的内容很多,但基本功的知识点是一致的。通过对钳工、方法、加工、品质、精度知识点的教学(摘要)。使学生懂得学习的要点和方法及实习学习的成本和收获的关系。由过去的被动型变为现在的主动型,引发学生自觉的思考;提高实习效率和工件质量的品质。以点代线代面的意识。  相似文献   

2.
作为浙江人的屠隆,诗文中有许多西湖风光的描写,在与杭州官员、社会名流交往的书信中也有较多关于岳王庙的议论.通过对屠隆诗文作品的解读来探究明代西湖岳王庙前塑像的变迁,以及明人对待岳飞、秦桧、王氏、万俟禼、张俊等人的看法及争议,由此透视出其特有的时代意义.  相似文献   

3.
悲剧在谢林的艺术体系中占有非常重要的位置.谢林把悲剧的本质解释为隐蔽的必然性对人类自由的干预的结果,悲剧冲突的结局是自由与必然都获得了胜利实现了和解,悲剧具有超越和提升的功能.谢林关于悲剧的论述,对黑格尔悲剧理论的形成产生了直接而深刻的影响.  相似文献   

4.
1896年现代奥运会成立的同时,国际体操联合会宣布成立,1932年竞技体操男子的6个项目确定下来.于是,繁多的,变化无穷的,造型美观又具有很高的锻炼价值与欣赏价值的体操动作应运而生,促使竞技体操进入一个新的时代.然而,面对如此多的体操动作,难度又如此大,我们不可能每一个动作都掌握.特别是对于体育教育专业体操专修的学生而言,大学4a,时间短还要学习其他技术和理论,年龄又相对大了,所以不能将所有动作学会.只能根据教学大纲或规则的要求,并结合自己的实际情况有所选择的掌握体操动作.也就是要特别掌握那些断面动作以及与此相关的断面教学方法.文章旨在通过对断面动作以及与此相关的断面教学方法的探索能对体育教育专业体操专修的学生和基层体操队的训练有所裨益.  相似文献   

5.
地震是世界上最凶恶的敌人,它给人类造成的灾难是难以估量的。在科学不发达的过去,人们对地震发生的原因,常常借助于神灵的力量来解释。随着社会的进步,人们则用科学的眼  相似文献   

6.
网络文化背景下的大学生道德问题浅析   总被引:2,自引:0,他引:2  
面对网络文化的冲击,大学生道德品质出现"滑坡"现象,表明社会的道德教育乏力.目前,社会对大学生的道德教育,主要是通过宣传和说教等方式进行理论的灌输,但这些积极的应对措施并没有从根本上解决大学生的道德滑坡问题.道德教育是在社会教育包括学校教育(他律)和大学生的自我教育(自律)二者交互作用中完成的,其中,大学生的自律是其中的决定性环节,大学生只有通过内省、慎独、自我磨练等方式,并审视自身的生活方式、生活态度,建立自己的学习型社团,在集体中反思自己,同时树立正确的网络观,摆脱虚幻的而进行实实在在的大学生活,才能达到人格的升华.  相似文献   

7.
在使用AutoCAD软件绘制组合体三视图的过程中,针对如何实现三视图中"主、俯视图长对正,主、左视图高平齐,俯、左视图宽相等"的三等规律,分别对给出尺寸标注的组合体的三视图的绘制和未给出尺寸标注的组合体的三视图的绘制两种情况提出相应的方法.结果表明,所采取的方法在AutoCAD软件中能够准确、快速地绘制组合体的三视图.  相似文献   

8.
本文从研究肢体残疾人服装的角度出发,对于残疾人的概念、种类,以及目前我国残疾人的大致状况进行了说明,对国内外肢体残疾人服装的研究状况进行了分析,就其着装问题进行了实际的调查.提出随着"以人为本"理念的深入人心以及和谐社会的不断深入发展,关注并研究肢体残疾人服装的设计是一项重要而有意义的工作.  相似文献   

9.
30年代左翼革命小说有些作品描绘了作家想象革命后将来临的理想社会的图景.这些文本所展开的"革命乌托邦"的图景明显是以当时中共苏维埃政权所承诺建立的"苏维埃农村"为蓝本.它们有马克思主义思想的根底,但更紧密地与中国共产党当时的政治实践联系着,凝聚了共产党当时的革命政治纲领和革命规划.显示出为中共苏维埃政权张本的征象.在乌托邦精神已成为人类普遍稀缺资源的当代,"革命乌托邦"小说为众人设想美好生活的精神和想象乌托邦的能力仍有动人的光辉.  相似文献   

10.
2001年7月13日是奥林匹克2008年举办国的投票日。之前的那几天,笔者正在泰国开会。因想了解北京申奥的进展,天天收看CNN和BBC。然而,这两家电视台当时对北京申奥的预测和评价都很差,理由之一就是北京的空气污染严重,会伤害运动员的健康。与北京竞争2008奥运会主办权的城市  相似文献   

11.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

12.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

13.
大肠杆菌pheA与tyrB基因的克隆与串联表达   总被引:3,自引:0,他引:3  
为探讨用基因工程的手段改良苯丙氨酸的发酵菌株,采用聚合酶链反应(PCR)的方法,从大肠杆菌总DNA中克隆得到了编码苯丙氨酸合成途中的两个关键酶基因-即分枝酸变位酶(CM)/预苯酸脱水酶(PD)基因pheA与苯丙氨酸转氨酶(PAT)基因tyrB,在大肠杆菌中进行了这两个基因的单个和串联表达。pheA和tyrB基因分别都能在λ噬菌体的PR启动子之后得到较大量的表达,在SDS-PAGE上出现清晰的条带,  相似文献   

14.
Tennessee Williams is considered as one of the most important American playwrights since World War II.The Glass Menagerie is his first successful drama,which describes a tragic situation of family and means to say that Man is unable to change the miserable life,no matter whatever means he try,This essay focuses on the analysis of the arrangement of the four main characters:Laura.Amanda,Jim and Tom to reveal the theme.Laura is fragile.Amanda is brave.Jim is vital.Tom is sensible.And all of them develop and try the different means to struggle against life,but fail tragically.With the evidence,the paper comes to conclusion naturally that Man is unable to change the miserable life,and he dooms to fail.  相似文献   

15.
介绍了四川溲疏属植物20种,5变种及1栽培变型,每种均有文献考证、学名订正、特征集要及产地和生境,新分类群D.leiboeneie P.He et L.C.Hu, D.piloea var.longiloba P.He et L.C.Hu,D.jinyangensis P.He eL L.C.Hu及D.longifolia var.deneitomentosa P.He et L.C.Hu均有详细拉丁文描述并附模式标本照片,还记录了两个四川省新分布种:D.bodiaieri Rehd.,D.rehderiana C.K.Schn.,对伞花亚组Subsect Cymosae Rehd.中建立的新系(Ser.Multiradiatae P.He,Ser.Pauciradiatae P.He)作了拉丁文补充描述。  相似文献   

16.
本实验室从正常狗脑中又分离获得一个暂称这为“60a”的肽。冻干粉经SephaderG-50和羧甲基纤维素CM22柱层析,再经反相高效液相层析纯化得最后样品,经SDS电泳和等电聚焦电泳鉴定均为一条带,分子量约8000,等电点在pH7.8左右;N-末端氨基酸为Met;自N-末端的部分氨基酸序列为:H2N-Net-Leu-Ser-Pro-Als-Asp-Leu-Thr-Asp-Ile-Leu-Phe-T  相似文献   

17.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

18.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

19.
Nonlinear transport of intense continuous beam in the axial-symmetric electrostatic fields is analyzed with the Lie algebraic method. The K-V particle distribution is adopted in the analysis. The results obtained can be used in the calculations of the intense continuous beam dynamics in the beam optical systems consisting of drift spaces, electrostatic lenses, and DC electrostatic accelerating tubes. A computer code has been designed for practical simulations. To meet the needs of accurate calculation, all the elements are divided into many small segments, the electric fields in each segment are regarded as uniform fields, and the dividing points are treated as thin lenses. Iteration procedures are adopted in the code to obtain self-consistent solutions. The code can be used to design low energy dc beam transport systems, electrostatic accelerators, and ion implantation machines.  相似文献   

20.
Being the primary media of geographical information and the elementary objects manipulated, almost all of maps adopt the layer-based model to represent geographic information in the existent GIS. However, it is difficult to extend the map represented in layer-based model. Furthermore, in Web-Based GIS, It is slow to transmit the spatial data for map viewing. In this paper, for solving the questions above, we have proposed a new method for representing the spatial data. That is scale-based model. In this model we represent maps in three levels: scale-view, block, and spatial object, and organize the maps in a set of map layers, named Scale-View, which associates some given scales.Lastly, a prototype Web-Based GIS using the proposed spatial data representation is described briefly.  相似文献   

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