丝绸之路与中国早期玻璃艺术

我国在商、周之交,就开始了早期的中西交流,而张骞西行后又开辟了新的中外来往的交通路线。我国的玻璃业尽管没能发展为重要的手工业门类,但它始终在持续而缓慢的发展,更重要的是,正是由于玻璃业的非主流,在发展过程中凸显了外部因素的重要性。丝绸之路在中国古代玻璃艺术的发展过程中起到了重要作用。     

浅谈GPS导航系统在油田运输管理中的应用

我油田地处华北东部,随着油田不断发展,对外承包业务愈来愈多。道路营运车辆也日益增多,营运范围也逐渐扩大,给道路运输经营管理与车辆合理调度工作提出了新的要求,而全球卫星定位系统的发展为道路运输管理的有效指挥、协调控制和管理提供了技术支持。本文结合GPS系统的原理,探讨GPS系统在油田运输管理中的应用。     

Human factors and road safety. Overview of research at the University of Michigan Transportation Research Institute between 1977 and 1986

This article presents a brief overview of the research performed at tge Human Factors Division of The University of Michigan Transportation Research Institute between 1977 and 1986. The focus of the research has been on human factors (ergonomics) aspects of road safety. Specifically, the research has dealt with the following issues: vehicle headlighting, vehicle rear lighting and signalling, vehicle displays and controls, vehicle components, conspicuity of vehicles, legibility of traffic signs and licence plates, driver reaction time, driver performance, stopping sight distance, driver seated position, individual differences (drivers with disabilities, older drivers), methods for measuring blood alcohol concentration, societal violence and traffic accidents, cross-cultural comparison of driver risk-perception, and theoretical issues.     

Groundwater as a source and pathway for road salt contamination of surface water in the Lake Ontario Basin: A review

In Ontario, there is limited comprehensive research regarding the contribution of chloride in groundwater to surface water systems. The delivery of chloride via groundwater can contribute to the degradation of the Great Lakes and their tributaries. Thus, this review intends to fill or identify knowledge gaps regarding assessing groundwater as a potential source of road salt, the single largest use of salt in urban cold region environments, contamination to surface water by synthesizing existing groundwater chloride research in the Lake Ontario Basin. Knowledge regarding source characterization, properties, pathways, and impacts of chloride in the environment is essential to evaluate the contribution of chloride via groundwater. Past groundwater chloride research in the basin is primarily concentrated in highly urbanized areas and has identified localized trends of increasing groundwater chloride concentrations in these regions; however, few investigations have been conducted in varying land uses (e.g., rural or less urbanized watersheds) or at sufficient temporal and/or spatial scales. Significant chloride accumulation is occurring in watersheds and aquifers within the basin. Concentrations are expected to increase until equilibrium is obtained, thus resulting in sustained yearlong elevated concentrations in tributaries. Recently, chloride loading to Lake Ontario has increased significantly, with groundwater inputs having the potential to support long-term increases in chloride concentrations in the lake. However, few studies have evaluated the explicit contribution via groundwater to Lake Ontario, and therefore a knowledge gap continues to exist. We provide a synthesis of additional research priorities to better understand the magnitude of groundwater chloride issues in the basin.     

Emission inventory of VOCs from mobile sources in a metropolitan region

Based on methodologies developed by US EPA, European EMEP/CORINAIR, and Australian NPI, and the former emission inventory in Korea, two methods were applied to 151 villages in northeastern Seoul, Korea to estimate emission of VOCs from line and area vehicle sources depending on vehicle types with different fuel types. A discharge coefficient method for the line source on the Eastern main road was calculated by multiplying the emission amounts per unit of mileage, and a fuel exhaust coefficient method for the area vehicle sources on other roads was determined as multiplying the emission rates by the actual consumption of excess fuel. Results indicated the methods could be adequate for estimating the amounts of mobile emissions when limited information on mobile emission is available. The methods can be used to develop the emission model for all VOCs emission sources (point and non-point sources), which provides input data of atmospheric models.     

基于地理位置的车载自组织网络路由协议的研究

由于车载自组织网络(Vehicular ad hoc networks)具有特殊的节点类型和信道特性,采用传统Ad hoc网络路由协议无法取得满意的性能。实现高速可靠的数据传输速率,需要研究新兴的路由算法。基于贪婪算法的地理位置辅助路由是目前VANET路由的主流思路。主要研究基于地理位置的路由协议,对GPSR(Greedy Perimeter Stateless Routing)协议进行改进,引入了向量的概念来改进GPSR路由协议的贪婪转发模式,即在选择下一跳节点时不仅要考虑到目的节点的距离,还要考虑城市环境中的十字路口节点,并增加了预测模式来预测车辆在十字路口的移动以提高路由协议的效率。     

基于位置范围的道路网skyline查询

随着无线通信和定位技术的发展,道路网skyline查询在基于位置的服务等方面越来越重要。考虑到现今道路网中位置隐私保护和定位设备的精度问题,用户在道路网上的位置通常用一个范围来表示。但是,已有的道路网skyline研究都是基于单一查询点。针对这一问题,研究了一种新的查询——基于位置范围的道路网skyline查询(RNS),提出了一种基于边界点替换的有效查询处理算法。另外,针对已有的道路网skyline查询中复杂的道路网距离计算对查询效率的影响问题,通过计算兴趣点在道路网上的有效skyline路段,将其与道路网信息融合,建立了道路网skyline模型。基于该模型设计了一种能有效支持RNS查询的道路网skyline索引SSR-tree,提出了基于索引的RNS查询处理算法。通过大量实验验证了所提方法的有效性,并比较了基于索引的算法在查询效率和精度上的提高。     

变——圜道哲学观的内核

圜道即循环之道。圜道观即循环论,其认为宇宙及宇宙间万物都永恒地循着周而复始的环周运动：发生、发展、消亡。它的展开论述始见于《吕氏春秋·圜道篇》,从先秦至今,圜道思想是中国传统文化中最根本的观念形态之一,中国传统哲学一直把“循环往复”理解为圜道观的最大特点,殊不知,“变”才是其真正的思想核心。     

城市道路景观设计研究

本文从城市道路景观的功能出发,分析了道路与景观的相互作用、道路景观的组成要素、道路景观设计的原则及道路景观设计的主要内容,从而引导道路设计者明确功能与景观并重、共性与个性共存、景观规划设计与道路规划设计同步进行的设计理念。