提高400m跑成绩的重要因素——速度耐力

提高短跑运动员的成绩,从训练的指导思想而言,一是速度能力,二是发展速度耐力.400m作为短跑项目,除了积极发辉他们的速度之外,还须重视速度耐力的训练.依据运动生理学研究成果及实践经验,阐述决定400m成绩的重要因素——速度耐力.     

Forecasting Multivariate Road Traffic Flows Using Bayesian Dynamic Graphical Models,Splines and Other Traffic Variables

Traffic flow data are routinely collected for many networks worldwide. These invariably large data sets can be used as part of a traffic management system, for which good traffic flow forecasting models are crucial. The linear multiregression dynamic model (LMDM) has been shown to be promising for forecasting flows, accommodating multivariate flow time series, while being a computationally simple model to use. While statistical flow forecasting models usually base their forecasts on flow data alone, data for other traffic variables are also routinely collected. This paper shows how cubic splines can be used to incorporate extra variables into the LMDM in order to enhance flow forecasts. Cubic splines are also introduced into the LMDM to parsimoniously accommodate the daily cycle exhibited by traffic flows. The proposed methodology allows the LMDM to provide more accurate forecasts when forecasting flows in a real high‐dimensional traffic data set. The resulting extended LMDM can deal with some important traffic modelling issues not usually considered in flow forecasting models. Additionally, the model can be implemented in a real‐time environment, a crucial requirement for traffic management systems designed to support decisions and actions to alleviate congestion and keep traffic flowing.     

Max‐infinitely divisible models and inference for spatial extremes

For many environmental processes, recent studies have shown that the dependence strength is decreasing when quantile levels increase. This implies that the popular max‐stable models are inadequate to capture the rate of joint tail decay, and to estimate joint extremal probabilities beyond observed levels. We here develop a more flexible modeling framework based on the class of max‐infinitely divisible processes, which extend max‐stable processes while retaining dependence properties that are natural for maxima. We propose two parametric constructions for max‐infinitely divisible models, which relax the max‐stability property but remain close to some popular max‐stable models obtained as special cases. The first model considers maxima over a finite, random number of independent observations, while the second model generalizes the spectral representation of max‐stable processes. Inference is performed using a pairwise likelihood. We illustrate the benefits of our new modeling framework on Dutch wind gust maxima calculated over different time units. Results strongly suggest that our proposed models outperform other natural models, such as the Student‐t copula process and its max‐stable limit, even for large block sizes.     

Reconceptualizing the generation in a digital(izing) modernity: digital media,social networking sites,and the flattening of generations

As digitalization binds society to an apparently perpetual acceleration, questions about the nature of time and speed have gained new urgency in the social sciences. Yet, theorizations of these issues have neglected their implications for social life and generations. Linking these lacunae, this article articulates how digital media and social networking sites (SNS) shape social life through cultural transformations in the generation. This article rationalizes predominant patterns of SNS user behaviors in the context of social theoretical and philosophical frameworks informed by Mannheim, Simmel, Adorno, Benjamin, Arendt, social presence, action, and acceleration theories to offer a relational reconceptualization of the generation as a set of social relations and processes for visualizing changing conceptions of time and speed in a digital (izing) modernity. This article introduces the concept of general and local generationing processes to articulate the processual nature of the generation and to assert that trends in SNS use and content production are underwritten by grammatical logics that collectively “flatten” separate traditional generations to form a cross-demographic and cross-temporal digital generation.     

知识流空间与高速铁路

知识流空间是借助信息技术和高速交通快速获得知识的组织体现,也是实现区域协调发展的有效手段。高速铁路是实现知识流的媒介,区别信息通信技术之处在于实现人的流动。高铁作为政府的公共政策,促进了面对面交流层面的知识流,而且通过影响人力资本流动、促进产业集聚与扩散、吸引投资、站区开发等方面影响了区域间知识流的结构,同时改变了区域间的知识联系强度。必须通过合理的政策手段完善高速铁路对知识流的影响。     

论元代文人篆刻崛起的文化背景

蒙元贵族对印章的大量需求、异族文化情趣对汉族文人的影响等因素相互作用 ,促进了元代文人对印章制度的探讨 ,促进了印文内容和用印方式的变化 ,促进了印章材料的多样化择取 ,并最终促成了以朱、王冕为代表的文人篆刻艺术的崛起     

动态路线行程时间研究

路段出行时间函数或路线行程时间函数在交通工程中已得到广泛应用,但现有模型在动态交通分配的实际应用中存在着不少问题。本文针对连续和间断两种不同交通流形式,借助于Ｇｒｅｅｎｓｈｉｅｌｄｓ模型和排队延误原理,建立了适用于动态交通分配的显式的动态路段出行时间函数表达式,从而进一步获得动态路线行程时间函数,为动态分配提供了一个重要的输入函数。     

矢量汉字分段处理

根据激光加工的特点 ,从传统字库中调出来的矢量汉字经过数据信息处理及转换 ,在二坐标激光加工机上加工 ,发现加工出的汉字轮廓粗糙难看、光顺性差 ,这是由于轮廓线多由碎直线段组成 针对这种情况 ,着重研究了为后续B样条、分段圆弧逼近 ,为防止字形失真而采用的分段算法     

高等教育大众化的工资影响研究

自扩招政策实施以来,我国高等教育飞速发展,但是伴随而来的毕业生就业问题也日益凸显。本文首先衡量了我国高等教育的发展现状,然后利用全国综合社会调查数据（CGSS-2006）实证分析了大众化进程对高校毕业生的工资影响。研究结果表明,高校毕业生工资优势正逐步缩减。众所周知,高等教育大众化是我国经济发展方式转型的客观需要,因此有必要从各方面着手,保障高等教育质量,改善毕业生就业状况,确保大众化进程的顺利推进。     

英语专业一年级学生阅读现状分析与对策

以包头师范学院英语专业一年级学生为调查对象,其阅读中存在的问题有：阅读速度较慢,阅读习惯不良,阅读策略使用率不高,阅读量不足等。改善学生阅读现状的教学策略有：拓宽阅读范围,培养各种阅读方法和技巧,发挥学生学习的主体性,进行有效的教学检测等。