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991.
992.
"概念包装"作为国际上流行的营销概念,所指的是企业用一种新的概念或一种特定的理念去定义自身产品的行为。本文浅议概念包装与酒类营销的融合。  相似文献   
993.
随着高等教育的发展和科学技术水平的提高,传统教学模式和手段受到了计算机和互联网为载体的科技手段的冲击。本文阐述了艺术专业大学英语课堂教学的特点,分析其局限性和改革的必要性;然后就现代信息技术手段在提高英语教学效果和促进艺术专业大学英语教学模式改革等方面的优势进行了分析,最后提出在这二者整合过程中该注意的问题。  相似文献   
994.
电工电子与自动化技术高职教育实训基地建设研究   总被引:1,自引:0,他引:1  
加强实训基地建设是办好高等职业教育的关键之一。电工电子与自动化技术高职教育实训基地是培养电子信息工程技术、应用电子技术、电子控制自动化等专业学生实践能力和职业能力的重要场所。对电工电子与自动化技术高职教育实训基地建设的必要性和作用进行了研究,提出了实训基地建设的目标、指导原则和建设内容。  相似文献   
995.
996.
This paper investigates the stability and stabilizability of complex-valued memristive neural networks (CVMNNs) with random time-varying delays via non-fragile sampled-data control. Taking the influence of gain fluctuations into account, a non-fragile sampled-data controller is designed for CVMNNs. Compared with the existing control schemes, the one here is more applicable and can effectively save the communication resources. The assumption on activation functions of CVMNNs is relaxed by only needing the complex-valued activation functions satisfying the Lipschitz condition. By constructing a suitable Lyapunov–Krasovskii functional (LKF), new stability and stabilizability criteria are derived for CVMNNs. Different from the existing results with the maximum absolute values of memristive connection weights, our ones are based on the average values of the maximum and minimum of the memristive connection weights. Finally, numerical simulations are given to validate the effectiveness of the theoretical results.  相似文献   
997.
This study examined aerodynamic properties and boundary layer stability in five cambered airfoils operating at the low Reynolds numbers encountered in motor racing. Numerical modelling was carried out in the flow regime characterised by Reynolds numbers 0.82–1.29 × 106. The design Reynolds number of 3 × 106 was used as a reference. Aerodynamics variables were computed using AeroFoil 2.2 software, which uses the vortex panel method and integral boundary layer equations. Validation of AeroFoil 2.2 software showed very good agreement between calculated aerodynamic coefficients and wind tunnel experimental data. Drag polars, lift/drag ratio, pitching moment coefficient, chordwise distributions (surface velocity ratio, pressure coefficient and boundary layer thickness), stagnation point, and boundary layer transition and separation were obtained at angles of attack from −4° to 12°. The NASA NLF(1)-0414F airfoil offers versatility for motor racing with a wide low-drag bucket, low minimum profile drag, high lift/drag ratio, laminar flow up to 0.7 chord, rapid concave pressure recovery, high resultant pressure coefficient and stall resistance at low Reynolds numbers. The findings have implications for the design of race car wings.  相似文献   
998.
Test procedures and their accuracy in determining critical fall height (CFH) on sporting grounds are paramount to player safety. The procedure currently adopted for synthetic turf in Australian football [1] consists of four consecutive drops at various drop heights at three test locations on the sample. The quantity and packing of the infill in third-generation turf and the pooling effect of the rubber particles with consecutive drops suggests that the current standard protocol may need re-assessment. Therefore, the purpose of this pilot study was to investigate whether current methods of testing for CFH are appropriate for third-generation synthetic turf or whether an alternative or adapted method needs to be developed. CFH was measured, using a HISUN Uniaxe-II Impact Tester, on 12 combinations of synthetic turf samples (four different products with three shock pad options). Three conditions were investigated on each sample; the existing protocol; an alternative 12 single-drop protocol and four single drops from the CFH determined from the existing protocol. A significant difference was found for both absolute and percentage difference between the existing and 12 single-drop protocol, with p = 0.001 and t = 4.33 and p < 0.001 and t = 6.03, respectively. There was also a significant difference between the CFH reached with and without a shock pad for both the existing protocol and the 12 single-drop protocol. The results of this pilot study demonstrate that differences do occur with alterations to the existing protocol and highlight the need for a more detailed characterisation of testing methods on third-generation synthetic turf and the response of surfaces to them.  相似文献   
999.
A number of recent studies have measured the extent and timing of segment rotation during the golf swing. A promising technique, instantaneous screw axis (ISA) theory, could provide a better expression of segment rotation. In Part 1 of this two-part study, the objectives are to identify the ISA of the pelvis, shoulders and left arm during the downswing, compute segment angular velocity relative to that segment’s ISA and verify that ISA theory is a valid tool to analyse segment rotation during the golf swing. Results indicate that for all subjects, at least 71% of marker velocity is a result of rotation about their respective ISA, when averaging results over the duration of the downswing, confirming that motion is primarily rotational. Furthermore, ISA position and orientation of each segment approaches, on average, the expected gross axis of rotation, confirming that motion about the ISA is representative of joint motion.  相似文献   
1000.
羽毛球项目是大学生喜爱的运动项目之一,但长期的教学实践发现传统技术教学模式不能真正使学生很好地理解羽毛球运动,所学的“技术动作”也难以在比赛中运用而转化为“技能”。为改变高校羽毛球选项课教学的现状,将“领会教学法”引入羽毛球选项课的教学,通过一年时间的教学实验取得了良好的教学效果。实验表明:应用领会教学法教学的班级学生...  相似文献   
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