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31.
定义了变换近环 ,然后证明了任意一个有单位元的近环与它的变换近环同构 ;任意一个无零因子近环与它的变换近环同构  相似文献   
32.
Lincoln Memorial University‐DeBusk College of Osteopathic Medicine (LMU‐DCOM) offers an optional three‐week summer Anatomy Boot Camp course (ABC) to facilitate students' transition into medical school and promote retention of anatomy subject matter. The pre‐matriculation program is a supplemental instruction course that utilizes a small group learning format. Boot camp instruction is led by teaching assistants and two anatomy professors. Enrollees gain early exposure to Medical Gross Anatomy (MGA) course subject matter, which is taught in the fall semester, and learn study skills necessary to excel in medical school. No grade is assigned for the course, therefore participants can study without the fear of potentially affecting grades. This study evaluates the effectiveness of the LMU‐DCOM ABC course using data from four consecutive summers. Independent two‐sample t‐tests were used to compare ABC to non‐ABC students for the following variables: incoming grade point average (GPA) and Medical College Admission Test® (MCAT®) scores, MGA written and laboratory practical examination grades, and final MGA course grade. Additionally, a 26‐question survey was administered to 2012–2014 boot camp participants. There were no significant differences in incoming GPA and MCAT scores. However, boot campers scored significantly higher on the first two lecture and laboratory examinations (P < 0.05) for each year of the study. Thereafter scores varied less, suggesting a faster head start for boot camp participants. Mean MGA final grade was on average 3% higher for the boot camp cohort. The survey feedback supports that the ABC course assists with the academic and social transition into medical school. Anat Sci Educ 10: 215–223. © 2016 American Association of Anatomists.  相似文献   
33.
A method for computing the visible regions of free-form surfaces is proposed in this paper. Our work is focused on accurately calculating the visible regions of the sequenced rational Bézier surfaces forming a solid model and having coincident edges but no inner-intersection among them. The proposed method calculates the silhouettes of the surfaces without tessellating them into triangle meshes commonly used in previous methods so that arbitrary precision can be obtained. The computed silhouettes of visible surfaces are projected onto a plane orthogonal to the parallel light. Then their spatial relationship is applied to calculate the boundaries of mutual-occlusion regions. As the connectivity of the surfaces on the solid model is taken into account, a surface clustering technique is also employed and the mutual-occlusion calculation is accelerated. Experimental results showed that our method is efficient and robust, and can also handle complex shapes with arbitrary precision. Project supported by the National Basic Research Program (973) of China (No. 2002CB312106) and the National Natural Science Foundation of China (Nos. 60533070, and 60403047). The third author was supported by the project sponsored by a Foundation for the Author of National Excellent Doctoral Dissertation of China (No. 200342) and a Program for New Century Excellent Talents in University (No. NCET-04-0088), China  相似文献   
34.
When hitting underground structures directly or exploding in rock-soil media near underground structures, the conventional weapons with large charge weight will make underground structures be subjected to strong shock vibration and cause personal casualty and damage of precision electronic equipments. The shock vibration has become one of the cardinal killing means of weapons. However, the existing methods of predicting structure shock vibration are limited evidently. In this paper the coupling coefficient of acceleration in clayey soil is obtained firstly. Subsequently based on repeated experiments of chemical explosion, after dimension analysis and by using method of multivariate stepwise regression, the calculation formulae of shock vibration acceleration for the underground structure are obtained finally. The formulae consider top and side explosion respectively, taking into account the effects of penetration depth, charge weight, distance to explosion center, rock-soil media, size of structure and buried depth. They are easy to use with high practicability and degree of confidence, and can provide credible evidence for prediction of shock vibration and vibration isolating design of underground structure.  相似文献   
35.
ANEWALGORITHMFORFASTHIDDENSURFACEREMOVALOFCOMPLEXOBJECTSFuYuqing(富煜清);HuangJinfa(黄金法);LinFeng(林峰)(DepartnientofRadioEnsineeri...  相似文献   
36.
安全工程专业实验课教学中的创新教育   总被引:1,自引:1,他引:1  
从创新教育的基本概念出发,对在安全工程专业的实验课教学中实施创新教育的必要性以及实施创新教育的可行性进行了研究。根据安全工程专业课程中所开设的实验特点及作者多年的教学实践,认为必须从激发学生创新意识、培养创新思维、提高创新能力、改革教学模式以及改革考核模式等各方面着手对实验教学进行改革和创新;“燃烧与爆炸学”实验课教学效果表明,在安全工程专业的实验课教学中实施创新教育是必要的和可行的。  相似文献   
37.
针对折线形坡面,通过经典库仑土压力理论,对挡土墙的土压力作出近似的计算。  相似文献   
38.
用布儒斯特角显微镜研究了花生酸分子成膜过程中单分子膜表面形貌的动态变化,发现在气/液界面上花生酸分子首先形成岛状分布,随着表面压的增加形成完整的单分子膜,而当表面压达到崩溃压后薄膜出现裂纹,分子膜重叠,形成多层膜。分析了花生酸单分子膜的形成机理。  相似文献   
39.
界面反应已成为界面自组装构筑的一个重要反应方面.从自组装膜的形成及自组装膜的气相、液相、膜上分子交联反应以及膜表面大分子寡聚体的设计组装等几个方面的表面反应对近年来自组装膜构筑方面的进展予以分析和综述.引用文献23篇.  相似文献   
40.
从山区至平原,地表水与地下水之间在不同地质地貌单元相互转换,是我国西北干旱区山前平原水资源的主要特点,直接影响到水资源开发利用模式的变化。随着和水利用率不断提高,减少了地下水补给来源,引起地下水位下降,泉水量削减,甚至枯竭,迫使泉灌区边城井灌。这在水资源西藏高原、森林资源、持续发展  相似文献   
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