久居高原中长跑运动员高原训练适宜海拔高度研究

通过采用文献资料法、比较法、归纳法等,对久居或世居高原中长跑和马拉松运动员高原训练的最佳海拔高度进行了研究.结果表明,久居或世居高原中长跑和马拉松运动员应当选择至少高于久居地或世居地342m作为训练地,其升高幅度为久居地或世居地的19.93%,所选择的训练地至少使运动员的相对最大摄氧量下降1.594 93 mL/kg.min,即比久居地或世居地下降2.75%,这为高原训练选择训练地点的方法学指标标准提供了参考.     

高原训练的地理学分析

高原训练是当前运动训练中的一个热点。与平原训练相比,它具有一定的特殊性和难度。该文采用文献资料法,从高原训练的生理学基础入手,分析了运动员进行高原训练时所要承受的来自两个方面的缺氧刺激和运动技能提高的理论基础。根据高原的地理分类法与运动训练的关系,从海拔高度、气温、太阳辐射等对人体的影响方面,分析了平原地区运动员和世居高原的运动员的高原训练特点,探讨不同居住地区运动员高原训练的适宜海拔高度,为运动员提高运动成绩提供依据。     

甘肃省山地自行车高原训练探索

以高原训练理论为基础,结合近年来山地自行车项目高原训练运动实践,对山地自行车项目高原训练的海拔高度选择,训练前准备,训练安排、运动负荷、参赛时间及注意问题等进行了探讨。     

基于兰州-榆中梯度环境的高原训练实践研究

甘肃是黄河上游的内陆省份,省内海拔一般在800~3000m,居民也多生活于这一海拔高度,属典型的亚高原人群。兰州-榆中地区海拔梯度差显著,是国内外专家公认的中长跑、自行车等项目"低住高练,高住低练"天赐理想场所。旨在重点介绍兰州-榆中高原训练网络的自然地理环境特点及其进行高原训练方面的优势,同时简要介绍甘肃近年来开展高原训练实践研究的经验和体会,使上述优势和特点得以充分发挥。     

我国田径训练基地布局与特点解析

本文主要采用文献资料、统计分析等方法,对榆中、多巴、海埂、兴隆、呈贡等高原训练基地的地理位置、气候特点、项目设置进行比较分析,揭示高原训练与自然环境的某些内在联系,对利用我国高原训练基地优势提高田径运动员成绩进行了分析研究,提出了充分利用我国高原训练基地优势提高田径运动员成绩的理论依据,从而根据不同地区气候季节性变化特点科学地选择和建立高原训练点,并为高原训练的地域性研究及运动选材提供参考。     

高原-亚高原交替训练对中性粒细胞的影响

研究目的：通过对12周高原-亚高原交替训练及其前后的中性粒细胞总数分布变化规律,进一步监控和探讨高原-亚高原交替训练对运动员免疫功能的影响。研究方法：采用临床应用广泛的血细胞分析仪,检测分析11名平均年龄为15岁的业余运动员,在进行12周的交替训练及其前后的中性粒细胞的变化。研究结果：高原-亚高原交替训练前后比较NEUT水平降低,表明12周交替训练对运动员细胞免疫功能产生的一定影响,其细胞免疫功能第2阶段明显较第1阶段稳定。建议：在研究类似大学生的青少年群体的运动员免疫功能时,应考虑到多因素的影响,如年龄、身体和心理发育等特征,周边环境,训练量和强度,尤其是海拔高度和缺氧环境等;在高原和亚高原训练中,应十分重视检测运动员各免疫指标的变化,以便及时发现及时调控营养和调整训练。     

从心理和生理指标变化谈船艇运动员的高原训练

高原训练受到了前所未有的重视,无论是在理论还是在实践过程中都取得了一定的突破,但是人们在进行高原训练时仍会遇到这样或那样的问题。尤其是不同的运动项目,其选择的海拔高度,训练周期、量与强度、时间、滞留天数以及下山参赛时间、调控等等也有很大差异。本文就船艇运动项目的特点、高原训练的指导思想及高原训练的监控等方面进行了探讨。     

对高原训练问题探讨

高原训练自上世纪50年代以来,得到迅速发展,高原训练的基础理论和训练经验的研究得到了重视和完善,但也暴露出高原训练中存在的问题,也是高原训练的热点问题.文章就模拟高原训练同传统高原训练之间的关系,高原训练应以能力提高为重点,训练的控制不能简单地依靠机能监测和评价、适应期问题、高原训练中速度训练问题和种族差异问题等几个方面对高原训练目前存在的一些问题客观地进行分析,提出高原训练的针对性建议.加强高原训练理论和实践方面的不断探讨.     

甘肃省女子中长跑运动员亚高原训练研究

运用访问调查、数理统计法、逻辑分析法等方法,针对甘肃省女子中长跑运动员亚高原训练的情况进行了追踪调查和研究.研究结果表明,世居亚高原人群、得天独厚的亚高原地理环境以及亚高原环境下的训练模式是甘肃省女子中长跑运动成绩长期保持较高水平的主要因素.     

高原训练对陕西省男子轻量级赛艇运动员运动能力与红细胞的影响研究

高原训练是指有目的、有计划地将运动员组织到具有适宜海拔高度的地区,进行定期的专项运动训练的方法。目前,高原训练仍是目前体育科研中的一大研究热点,已得到国内外体育界的普遍重视,并建立了一些新的训练手段及模拟训练方法,同时高原训练的方法也不断改进,参与高原训练的项目已由原来的一些主要耐力运动项目,发展到几乎包括了所有的奥运会项目。各国的训练实践也证明,高原训练是发展有氧耐力的一种有效的训练方法。因此,本文通过观察高原训练提高运动成绩的同时,观察平原-高原-平原这种交叉训练对机体血液红细胞的影响,旨在探索高原训练提高运动成绩的可能机制,为科学的进行高原训练提供理论依据。     

An Index mechanism for multi-scale view in spatial databases

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.     

Wuhan University Journal of Natural Sciences TOTAL CONTENTS

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Advances in broadband wireless communications under high-mobility scenarios

Future mobile communication systems aim at providing very high data transmission rates, even in high-mobility scenarios such as high-speed wheel-track trains, maglev trains, highway vehicles, airplanes, guided missiles or spacecraft. A particularly important commercial application is the strong and increasing worldwide demand for high- speed broadband wireless communications （up to 574.8 km/ h test speeds or 380 km/h commercial speeds） in railways, providing data, voice and video services for applications such as onboard entertainment services to passengers, train control, train dispatch, train sensor status handling and sur- veillance. In such high-mobility scenarios, there are a number of communication challenges, including fast hand- over, location updating, high-speed channel modeling, estimation and equalization, anti-Doppler spreading tech- niques, fast power control, and dedicated network architec- ture. Because signal transmission in very high-speed scenarios will inevitably experience serious deterioration, it is imperative to develop key broadband mobile communi- cation techniques for such high-speed vehicles.     

Perspherical Approaches for Electrons in Atoms and Charged Excitons in Quantum Wells

Instead of following Fock’s expansion,we solve the Schrodinger equation for some quantum mechanical manybody systems such as electrons in atoms and charged excitons in quantum wells in a similar way in hyperspherical coordinates by expanding the wave functions into orthonormal complete basis sets of the hyperspherical hannonics(HHs)of hyperangles and generalized Laguerre polynomials(GLPs)of the hyperradius.This leads the equation to     

Scale-based spatial data model for GIS

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.     

英文诗歌中的喻类修辞

为了有助于提高英文爱好者的个人情操、文化素养和学习兴趣,以及专业人员对英语学习和研究进行多途径的探索,本文通过一些精选诗歌的引证和分析,着重论述了喻类修辞法在英文诗歌中的运用其及效果。     

Man Is Unable to Change the Miserable Life——Analysis of the Arrangement of Four Characters in The Glass Menagerie

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.     

Characterization of root-nodulating bacteria on Retama raetam in arid Tunisian soils

The aim of this study is to investigate the diversity of Retama raetam root-nodule bacteria isolated from arid regions of Tunisia. Twelve isolates, chosen as representative for different 16S rRNA gene patterns, were characterized by 16S rRNA gene sequencing and phenotypic analysis. Isolates were assigned to Sinorhizobium, Rhizobium and Agrobacterium. Symbiotic properties of Sinorhizobium and Rhizobium isolates showed a large diversity in their capacity to infect their host plant and fix atmospheric nitrogen. Strain RK 22 identified as Rhizobium was the most effective isolate.     

An Affordable Accurate Evaluation of the Binding Conformations Predicted by Molecular Docking Studies in Bio-System

正Recently,docking has been widely used to predict the binding-modes of protein-inhibitors,when the crystal complexes structure was absent.Most docking algorithms are able to generate a large number of probable conformations,it,however,is difficult to effectively evaluate these docking poses and identify the most reasonable bindingmode.In the present study,on the basis of the crystallographic data of human 3-hydroxy-3-methylglutaryl coenzyme     

WIMAX与WI-FI技术分析及联合组网

介绍了WiMAX与Wi-Fi两种无线宽带接入技术,并对两者之间的关系及相互之间的影响做了对比及分析,并对WiMAX的关键技术进行了详细说明,最后对两者的联合组网方式做了简单的探讨。