一类条件不等式的特征及证法     

卫福山 《河北理科教学研究》2011,(2):13-15

形如∑a=1（即已知条件类似为a,b,C∈R’,a＋b＋c=1）的不等式证明的方法各种各样,但仔细研究还是有规律可循的,选择什么样的证明方法要根据所证明不等式的具体形式,本文拟对这样一类条件相同的不等式的形式加以分析,并对证明方法的选择加以指导．  相似文献   

《诗经》中“水-爱情”模式的生成与表现     

姜莉丽  郝超 《哈尔滨学院学报》2011,32(7):96-99

水是中国古代文学中重要的审美意象,“水-爱情”的书写模式更是值得关注的。文章以《诗经》中的爱情诗为例,分析了水成为审美意象的成因,并探寻了水与爱情的共通之处。  相似文献   

人文关怀视阈下的高校思想政治教育     

姜俊丹 《哈尔滨学院学报》2011,32(4):132-134

体现人文关怀,既是我国高校学生思想政治教育的一个基本理念,也是高等学府应有的大学精神,更是学生思想政治工作自身内在属性的必然要求。只有这样,才能使学生真正感受到来自学校的温暖和尊重,有利于培养彼此的信任和情感,使思想政治教育在和谐、轻松、对等的氛围中开展下去,保证学生思想政治工作达到预期的效果。  相似文献   

管窥南朝与北朝对“郡望”的不同态度     

任玮 《哈尔滨学院学报》2011,32(1):119-122

虽然＂郡望＂一词对南北朝社会影响深远,但南朝与北朝对汉族大姓望族的认可态度不同,南朝与北朝冒籍现象的程度不同,南朝与北朝的人们对祖籍的态度不同。之所以会出现不同的态度,是因为南朝与北朝政权依靠的力量、迁都的影响以及文化方面存在差异,而且南朝对于墓志碑铭、谱系的管理制度相对北朝也更为健全和完善。  相似文献   

网络环境下大学英语教师反思能力培养的实效性研究     

孙维  陶玮  周营 《教育理论与实践》2011,(6)

开展反思性教学是教师专业发展的有效途径。通过一项基于石家庄铁道大学非英语专业部分教师和学生反思网络环境下大学英语教学的行动研究,可以看出网络环境下的大学英语教学急需解决的主要问题是大学英语教师角色的转换、教学课件制作和使用的科学性、网络环境下互动教学的开展。在网络环境下开展大学英语教师反思能力培养的行动研究,对教师的教学能力和专业发展以及全面提高大学英语教学的质量,有着重要的现实意义。  相似文献   

WPT-based modal control on distributed structures with MRF-04K damper     

林伟  李忠献  张根明  黄鹏云 《天津大学学报(英文版)》2011,17(6):397-403

The magnetorheological (MR) fluid damper-based semiactive control systems have received considerable attention for protecting structures against natural hazards such as strong earthquakes and high winds. In this paper, a novel modal controller using wavelet packet transform (WPT) is proposed for the vibration control of distributed structures. In the proposed control system, the WPT method is utilized to decompose the acceleration measurement and select the modes containing most of the WPT energy component as the dominant modes. Then, a modal controller is designed to control the dominant modes and the optimal active control force is solved. Finally, Clipped-optimal con- trol law is adopted to determine the voltage applied to each MR damper. A Kalman-filter observer, which estimates the full controlled modal states from local accelerometer feedbacks, is designed for rendering the controller to be more applicable to distributed structures with a large number of degrees of freedom. A numerical example of a stadium roof structure installed with MRF-04K damper is presented. The effectiveness of the controller is evaluated under both Tianjin and El Centro earthquake excitations. The superior performance and adaptability of the controller for versatile loading conditions are demonstrated through the comparison with traditional truncated modal controller.  相似文献   

引力透镜效应在宇宙学中的研究及应用     

杨淑敏  张伟  吴怡芬  郭慧芳 《喀什师范学院学报》2011,32(6):39-42

引力透镜效应已经成为当前探测宇宙中物质分布最有效的工具之一,因其光线偏折不依赖于物质的组分和状态,所以它很适合于探测包括暗物质在内的所有物质在宇宙中的分布.在引力透镜效应的提出及发现基础上,根据引力透镜的分类,分述了强引力透镜、弱引力透镜和微引力透镜,并讨论了引力透镜效应在宇宙学中的应用.  相似文献   

Tribology Performance and Adhesive Strength Evaluation of TiAlSiN Coating     

姜峰  谢鸿  融亦鸣  言兰 《天津大学学报(英文版)》2011,17(4):248-253

Scratch test and friction test were performed to evaluate the internal and external interface behaviors of TiAlSiN coating, respectively. The critical compressive and shearing stress of coating failure during scratch test were calculated and the values are 30.84 MPa and 4.98 MPa respectively. The average friction coefficients of TiAlSiN coating against 2Cr12Ni4Mo3VNbN steel are 0.70 (sliding speed 50 m/min), 0.63 (sliding speed 100 m/min), and 0.81 (sliding speed 150 m/min). The elements diffusion was analyzed by EDS. Al and Si element of coating material diffuse to the steel disc, except Ti element. The oxidation decreases with the increase of sliding speed, but the adhesion increases with the increase of sliding speed. More Al element diffuses to the steel disc at the high sliding speed, but the diffusion of Si element keeps almost constant at different sliding speeds.  相似文献   

Experimental and FEM Study of Coated and Uncoated Tools Used for Dry Milling of Compacted Graphite Cast Iron     

陈明  姜立  郭国强  安庆龙 《天津大学学报(英文版)》2011,17(4):235-241

Compacted graphite cast iron (CGI) has been the material for high-power diesel engines recently, but its increased strength causes poor machinability. In this study, coated and uncoated carbide tools were used in dry milling experiment and FEM simulation to study the machinability of CGI and wear behaviour of tools. The experimental and FEM simulation results show that coated tool has great advantage in dry milling of CGI. SEM and EDS analysis of tool wear indicate the wear morphology and wear mechanism. Adhesive wear is the main mechanism to cause un-coated tool wear, while abrasive wear and delamination wear are the main mechanism to cause coated tool wear. Stress and temperature distribution in FEM simulation help to understand the wear mechanism including the reason for coating peeled off.  相似文献   

研究新疆高校思想政治教育特殊性的意义及内容     

姜勇 《喀什师范学院学报》2011,32(2):79-82

新疆高校思想政治教育特殊性问题的研究是思想政治教育研究工作的一个薄弱环节。开展此项研究,对提高思想政治教育的效果和质量,促进思想政治理论课的教学改革,加强思想政治教育学科的建设,制定符合新疆高校实际的教育政策有着十分重要的意义。研究新疆高校思想政治教育特殊性问题,必须界定新疆高校思想政治教育特殊性问题的含义及其涵盖的内容。  相似文献