怎样提高篮球教学课的吸引力

篮球课的教学质量是受诸多因素影响的 ,其中提高篮球课的吸引力教师是关键。教师必须充分利用教学艺术和教学规律 ,从实际出发 ,选用适当的方式、方法 ,来吸引、激发学生的兴趣和注意力 ,最大限度地调动学生的积极性、主动性 ,使他们思想集中 ,较好地掌握技、战术和运动技能。这样 ,篮球课的教学质量才会得到提高     

利用磁信息追踪沉积物物质来源的定量方法

矿物磁性测量由于其具有简便易行、不带破坏性和用途多样性的特点已成为环境研究的一种新方法。本文以美国马里兰州罗德河流域为例,在自然物质磁性测量的基础上,运用聚类分析、多元回归分析和线性规划等方法,对沉积物来源进行了定量的估算。研定结果表明,河口湾沉积物来源组成具有明显的变化。这个变化与样芯的孢粉分析结果有惊人的吻合之处,反映了流域环境演变的历史。结果也表明,就一些实际问题而言,这种定量分析的方法比以前的定性描述方法更加实用和有效。     

载流直导线的电磁场特性分析

利用狭义相对论分别对同一载流直导线外一个运动电荷的受力情况在几种常用的参考系中分析,得出电磁场是一个协变的统一体的结论。     

二维拟线性微分系统解的全局吸引和有界性

本文讨论一类二维拟线性微分系统解的有界性及渐近性质，推广了近期一些作者的结果。     

Share equations in econometrics: A story of repression,trustration and dead ends

Share equations play an important role in applied economic research, notably in marketing and demand analysis. Both market shares and budget shares have been used as dependent variables in econometric models which were partly motivated by microeconomic theory. However attempts of econometricians (and other statisticians) to treat share equations adequately led mostly to unsatisfactory approaches: Some researchers although admitting that shares satisfy a sum constraint simply repressed the fact that shares cannot be normally distributed. Some researchers looked in vain for a stochastic specification which at the same time is consistent and allows a flexible covariance structure. Last not least almost nobody has properly taken care of additional problems arising from dynamic share models. The paper discusses these three issues and proposes a possible way out of this dilemma which was first suggested by Aitchison (1982) and has been applied to econometric demand analysis by Considine and Mount (1984). Demandtheoretic implications as well as methods of estimation are discussed. An example using German import data illustrates some of the results. Research for this paper is financially supported by Deutsche Forschungsgemeinschaft, SFB 178 “Internationalisierung der Wirtschaft” at the University of Konstanz. Some results reported in this paper have been achieved jointly with Karl Ringwald whose permission for using unpublished joint work is gratefully acknowledged. Critical remarks by an anonymous referee helped to improve the exposition of the paper.     

圆波导TM_(mn)模回旋潘尼管

本文提出了圆波导TM_(mn)模回旋潘尼管的动力学理论。求解了引导中心的漂移以及产生的偶极电流。因此,本文结果不但适用了回旋潘尼管,而且比以往结果更为精确地描写回旋管。     

Pedohebephilophobia: Response to Commentaries by Janssen,Malón,and O’Carroll

ABSTRACT. There is very limited research on women who perform in adult films. The current study used a discovery-oriented qualitative methodology to examine the responses of 176 female actresses in the adult entertainment industry to questions regarding the reasons for becoming involved in the pornography industry, as well as their likes and dislikes of the work. The most frequent reasons for joining the industry included money, sex, and attention. Only one participant indicated that she was coerced into becoming a porn actress. The most favorable aspects of their work included money, people, sex, and freedom/independence, whereas the most frequently reported dislikes included people, sexually transmitted diseases, and exploitation. The responses from this study provide valuable insight from a large sample of a difficult-to-access population of pornography actresses on why they chose to become involved in the pornography industry and on positive and negative facets of their work. The results may be used to question many of the stereotypes that society commonly holds regarding attributes of female pornography actresses.     

基于三维磁场的机械伤残控制系统

系统以AT89C52单片机为控制单元,介绍了一种由4个线性霍尔传感器构成三维磁场测量的机械伤残控制系统.将含有磁体的特殊物品佩戴在手腕上,利用系统测量磁体与“0”点的距离,间接地检测“人手”的位置,以达到保护人体的目的.该系统具有结构新颖、电路简单、控制准确、生产成本低廉和体积小巧等优点,特别适合应用于机械设备的安全控制.     

生态环境的亲和作用对建筑设计的影响

生态环境的亲和作用指的是生态环境要素之间的相互吸引 ,又相互排斥 ,协调共存的特性。亲和作用目的是保持环境要素的共存 ,而要素间相互作用则是共存的前提。亲和作用具有两重性 ,它是吸引性和排斥性的统一体。生态环境的亲和作用主要通过两个因素对单体及群体建筑产生影响 :地景因素和气候因素。     

高频磁结构与磁极限关系的研究与现状

动态磁谱参数,包括微波磁导率实部和虚部、截止频率等,与材料本征磁参数、结构形貌参数的制约关系,作为高频磁性材料性能的标杆和发展方向的理论指导,一直伴随着高频磁性材料的发展而不断演变,是动态磁化物理理论研究和磁性功能材料设计所关注的核心问题。磁结构决定了极限关系式的形式,而极限关系式为磁结构的设计、应用和发展提供了理论指导。该文综合介绍了近年来国内外高频磁结构和磁极限关系研究的发展情况,着重分析两者相辅相成的关系和研究方法,并归纳了该领域的发展趋势和存在的一些主要问题。