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1.
采用高速摄影方法,揭示了我国甲级男排3种扣球技术的起跳和空中击球挥臂动作速度的运动学特征。并通过与世界优秀扣球手的比较,找出了我国甲级男排选手的差距,为扣球的教学与训练提供了理论依据。  相似文献   

2.
韩东 《燕山大学学报》2005,29(6):557-560
用运动生物力学的电影摄影和影片解析及体育统计、教学实验的方法,对原中国女排队员、北京体育大学、沈阳体育学院排球专业大学生及燕山大学排球特招运动员分别进行了调研、统计和实验指出:目前,排球扣球技术动作大致有两种,一种是屈臂扣球,一种是小抡臂扣球。采用屈臂扣球运动员的肩部肌肉损伤率高于采用小抡臂扣球的。建议采用屈臂扣球的运动员要努力发展自己三角肌前部的力量和柔韧性。  相似文献   

3.
排球扣球技术的生物力学分析   总被引:1,自引:0,他引:1  
运用生物力学的分析方法,对排球扣球技术动作,特别是对助跑、起跳、空中击球和落地等动作进行了研究,总结和归纳了动量矩定理及动量矩守恒定律运用到排球扣球技术中的一些规律,其目的是规范排球扣球技术动作,引导学生掌握正确的扣球技术,提高扣球的质量和效果.  相似文献   

4.
以排球扣球过网点为切入点,借助几何模型,结合运动技能形成机制,在传统教学法的基础上对排球扣球技术进行干预实验研究。结果表明:在排球扣球技术中应用几何模型引导教学,有利于缩短教学周期、提高教学质量,优化教学效果。  相似文献   

5.
论排球扣球技术的教学方法   总被引:1,自引:0,他引:1  
扣球是排球基本技术中攻击性最强的一项技术,也是排球各项技术教学中动作最复杂、最难掌握的一项技术.因此教师要熟悉扣球技术各环节要领,并能熟练运用讲解、示范、试做、纠正、练习的教学步骤,使练习者尽快学会并掌握好扣球技术这一排球运动中的重要技术动作.  相似文献   

6.
主要采用文献资料法和逻辑推理法,归纳和总结排球扣球核心力量训练的相关研究,从排球扣球技术动作特点的角度分析核心力量在扣球中各个环节所起的作用,结果表明:核心力量训练对提高排球专修学生的扣球能力有一定作用。  相似文献   

7.
核心力量训练提高排球扣球能力的理论研究   总被引:1,自引:0,他引:1  
付婷婷 《科技信息》2010,(20):262-262
本文参阅了大量文献确定排球运动动员扣球用力动作链,来寻找增强排球运动员扣球能力的核心力量的训练方法,其主要作用在于能够提高排球运动员在扣球中控制和维持平衡的能力及由核心向四肢及其他肌群的能量输出、预防运动损伤.  相似文献   

8.
本文从建立正确的正面扣球概念,分解及完整动作教学及练习三个方面讨论了排球正面扣球技术教学中应注意的问题。  相似文献   

9.
乔玉威 《科技资讯》2013,(33):201-201
通过对江苏油田女职工排球比赛的研究,分析业余女子排球爱好者扣球这一技术环节的现状、特点、存在的问题以及扣球技术在在基层排球比赛中的作用与意义,通过数据的处理与分析提出扣球技术改进的方法与建议,为广大排球爱好者提供参考。  相似文献   

10.
试从运动生物力学的理论 ,对排球技术中扣球挥臂时上肢各关节进行运动学分析 ,探求挥臂的时机、速度 ,击球动作的合理性、有效性及扣球的最佳击球点  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

15.
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   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

19.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

20.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

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