ATM网VBR编码会议电视业务模型的研究

文章研究了ATM网中VBR编码的会议电视业务的模型，提出一阶自回归、瑞利分布残差而不是高斯分布的AR序列模型──RAR（1），实验表明，该模型能产生足够多的大信元帧数，这对于研究信元丢失率特性具有至关重要的影响，而且简单实用。此外，RAR（1）模型在较少（16个）和较多（128个）VBR信源统计复用时，能很好地拟合实际的会议电视业务的统计数据。     

Modeling video sources for real-time scheduling

What is the impact of the autocorrelation of variable-bit-rate (VBR) sources on real-time scheduling algorithms? Our results show that the impact of long term, or interframe, autocorrelation is negligible, while the impact of short term, or intraframe, autocorrelation can be significant. Such results are essentially independent of the video coding scheme employed. To derive these results, video sequences are modeled as a collection of stationary subsequences called scenes. Within a scene, a statistical model is derived for both the sequence of frames and of slices. The model captures the distribution and the autocorrelation function of real-time video data. In previous work, the pseudoperiodicity of the slice level auto-correlation function made it difficult to develop a simple yet accurate model. We present a generalization of previous methods that can easily capture this pseudoperiodicity and is suited for modeling a greater variety of autocorrelation functions. By simply tuning a few parameters, the model reproduces the statistic behavior of sources with different types and levels of correlation on both the frame and the slice level.     

NUMERICAL MODEL FOR DYNAMIC SIMULATION OF TRAFFIC FLOW

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钢纤维混凝土在南钢大道工程中的应用

钢纤维混凝土是一种性能优良的新型复合材料，与普通混凝土相比，其抗拉、抗弯、抗裂及耐磨、耐冲击、耐疲劳等性能都有显著提高，它不仅可使路面厚度减薄，工程缝间距加大，改善路面的使用性能，延长路面使用寿命，而且还可节省工程造价，缩短施工工期。文中结合南钢大道路面工程实际，主要介绍了钢纤维混凝土的施工及质量控制要点。     

Network traffic prediction based on a new time series model

Fast and accurate methods for predicting traffic properties and trend are essential for dynamic network resource management and congestion control. With the aim of performing online and feasible prediction of network traffic, this paper proposes a novel time series model, named adaptive autoregressive (AAR). This model is built upon an adaptive memory‐shortening technique and an adaptive‐order selection method originally developed by this study. Compared to the conventional one‐step ahead prediction using traditional Box–Jenkins time series models (e.g. AR, MA, ARMA, ARIMA and ARFIMA), performance results obtained from actual Internet traffic traces have demonstrated that the proposed AAR model is able to support online prediction of dynamic network traffic with reasonable accuracy and relatively low computation complexity. Copyright © 2005 John Wiley & Sons, Ltd.     

新疆重质混合原油研制高等级道路沥青

对利用新疆重质混合原油生产的减压渣油作为基质沥青制备高等级道路沥青进行了研究。考察了低硫石蜡基原油（A）和含硫环烷-中间基原油（B）的掺炼比对基质沥青四组分组成的影响，减压渣油软化点与基质沥青四组分组成的关系，以及添加剂对改进沥青性质的作用。由此得出原油（B）的合适掺炼量，减压渣油软化点的控制范围和优化的生产工艺条件，调合出了符合GB／T18150—2000和JTGF40—2004要求的高等级道路沥青。     

浅谈南坪快速路道路照明设计

通过南坪快速路道路照明设计实例，介绍快速路道路照明设计方法和主要内容。     

Success and failures in urban transport planning in Europe—understanding the transport system

Technological determinism has become a kind of religion for many people since it appears to offer solutions for societal problems as never before in history. Transport is one of the fascinating technology branches developed during the last 200 years. Effortless movement over long distances has become possible for car users as long as cheap fossil energy is available. However, the effect of fast transport on urban structures and society was not taken into account when developing these technical means. Technologists and economists have used indicators for expected benefits of these fast transport modes without taking into account the real system effects on society and urban structures. Plausible assumptions and hopes instead of scientific understanding of the complex system are used in practice. In contradiction to widely held beliefs of transportation planners, there is actually no growth of mobility if counted in number of trips per person per day, no time saving by increasing speed in the system, and no real freedom of modal choice. Modal choice is dependent on physical and other structures, the artificial environment built by urban planners, transport experts and political decisions. The core hypothesis of traditional urban and transport planning ‘growth of mobility’, ‘travel time saving by increasing speed’ and ‘freedom of modal choice’ are myths and do not exist in the real urban and transport system. This is the reason why urban planning and transport planning based on traditional non-scientific assumptions is creating continuously not only more transport problems, but also environmental and social as well as economic problems all over the world, where these principals are applied. Urban transport planning in Europe, understanding the transport system and the solutions are presented in this paper.     

试论安定性不合格消石灰对柔性路面质量的影响

由于过烧石灰的存在和消解不当等原因，造成消石灰安定性不合格，当石灰稳定类路面结构成型或投入使用后，消石灰中的生石灰颗粒开始吸收周围水分，慢慢消解，消解过程中发生体积膨胀，对路面产生破坏。解决石灰安定性问题对防止公路前修后坏，延长路面使用寿命具有积极的现实意义。     

道路与匝道中线自动绘制的算法与实现

道路与立交匝道平面中线的计算机自动绘制是道路路线CAD软件的核心功能之一,在道路工程计算机动态交互式设计、计算机辅助成图方面具有基础性作用.依据道路中线线形的曲率变化特点,推导了道路中线坐标计算的通用数学模型,并根据一个工程实例在通用图形系统AutoCAD环境下实现了道路与匝道中线的自动绘制.