Multiclass P2P networks: Static resource allocation for service differentiation and bandwidth diversity

We propose a multiclass fluid model for BitTorrent-like content-distribution systems. The new model can model heterogeneous peers, in which peers have different access bandwidths. The model can also model BitTorrent-like systems which provide differential service (for example, first class and second class service) to the participating peers. The fluid model leads to a non-linear system of differential equations with special structure. For the service differentiation problem, we prove that the system of differential equations admits a unique stable equilibrium, that we compute in closed-form. We also provide the average download times for both classes. For the bandwidth diversity problem, we show that the system of differential equations has a stable state that may depend on the initial conditions. We compute the average download time of both classes for each reachable steady-state.     

Achieving educational technology standards: the relationship between student teacher's interest and institutional support offered

Having in mind the need for an increased attention to the importance of pre‐service teacher development concerning technology, this study examined teachers' interest to attain educational technology standards (Interest) in terms of their computer attitude (Attitude) and the professional support they received to attain these standards (Support). The study used a sample of 39 mathematics student teachers and 62 elementary student teachers. The two groups only differed in Support favouring elementary student teachers, who, contrary to mathematics student teachers, received some basic instruction concerning ET standards.Despite these differences in Support, the two‐group path analysis applied revealed that, for both student teachers, the direct effects of Support on Attitude and of Attitude on Interest were positive and significant. On the other hand, the total and direct effects of Support on Interest, although positive, were insignificant. However, because of significant indirect effects, the impact of Support on Interest was mediated through Attitude in both groups. These findings support the view that in order to develop Interest, Support should focus on developing Attitude, which may hold true in general not depending on student teacher type and the level of Support. Implications for further research and (pre‐service) teacher professional development are examined.     

The assignment of job-attitude items to subscales.

An attitude questionnaire, for use with the personnel of a Great Lakes shipping concern, was constructed using rational judgments to assign items to areas of the questionnaire. The areas were nominally those suggested as invariant by Wherry. The degree of agreement between the rational sort and the areas named from the invariant factor characteristics was determined. Attitude characteristics of the surveyed group as well as mechanical and response artifacts are suggested as providing partial explanations of the differences found. Items identified as critical through use of several item indices are compared to evaluate index utility. (16 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Applied genetic evaluations for production and functional traits in dairy cattle

The objective of this study was to review the current status of genetic evaluation systems for production and functional traits as practiced in different Interbull member countries and to discuss that status in relation to research results and potential improvements. Thirty-one countries provided information. Substantial variation was evident for number of traits considered per country, trait definition, genetic evaluation procedure within trait, effects included, and how these were treated in genetic evaluation models. All countries lacked genetic evaluations for one or more economically important traits. Improvement in the genetic evaluation models, especially for many functional traits, could be achieved by closing the gaps between research and practice. More detailed and up to date information about national genetic evaluation systems for traits in different countries is available at www.interbull.org. Female fertility and workability traits were considered in many countries and could be next in line for international genetic evaluations.     

根据钻孔资料确定地下岩层产状——通用地质坐标系应用实例(之四)

根据钻孔资料确定地下岩层产状是一个比较复杂的问题。利用赤平极射投影网上的小圆相交方法,可以求得倾斜钻孔资料地下岩层的可能产状,但赤平极射投影网上的小圆作图比较复杂。利用通用地质坐标系可直接在球面投影上计算出两个小圆的交点,能更快更准确地得到结果。     

如何看待马克思主义的“东方理论”——兼论马克思主义的理论视角

文章就如何看待和理解马克思主义的“东方理论”以及由此而产生的种种分歧发表看法。认为，我们必须从科学的态度出发，在认真把握马克思恩格斯的理论视角的基础上，正确理解和看待马克思主义的“东方理论”。     

情感过滤法在外语教学中的运用

影响外语学习的因素除了客观因素外,学习者学习外语的动机、态度、焦虑和自信心很大程度上影响着他们的学习效果,那么教师在外语教学中巧妙的运用情感过滤非常重要.     

名人广告对“粉丝”消费态度的影响研究

文章构建了关于名人广告对消费态度影响的四因素模型,来探讨名人广告对“粉丝”消费态度的影响。研究表明名人广告对“粉丝”消费态度产生了积极的影响,其中“粉丝”对于名人代言的产品好感度相对较高,且购买行为倾向较大;名人广告对“粉丝”消费态度影响因素中最关键两个因素分别为名人吸引力和名人—“粉丝”相似性;另外,广告创意因素对于“粉丝”消费态度的影响也是不可忽视的。     

转型时期大学生人生观价值观的塑造与培养

高等学校要把帮助大学生树立正确的人生观价值观放到育人工作首位,帮助大学生正确认识和处理在人生追求和价值取向中的四个关系,在帮助他们树立正确的人生观价值观时抓好四个环节。     

论企业竞争中的先动优势、风险态度和预期收益

运用博弈论的基本理论，根据企业决策中的行动先后所产生的收益差别，说明了市场竞争中先行动者的收益优势，以及拥有信息较多者收益未必高的道理；通过利益分配中的讨价还价模型，分别就风险偏好、风险中性和风险规避等三种类型企业，分析了常和博弈中的风险态度和预期收益之间的关系，得出了二者正相关的结论，最后指出，市场信息获取固然重要，但更重要的是尽快付诸行动，同时在行动中勇于承担风险，这样才能获得理想的收益。