Use of system dynamics for proper conservation and recycling of aggregates for sustainable road construction

A significant amount of mineral aggregates are used in constructing, rehabilitating and maintaining roads. As local (nearby) quarries get exhausted, aggregates need to be hauled from sources that are at ever-greater distances. Hence, over time the cost of trucking as well as the amount of emissions generated by trucking increases with a decrease of local natural aggregate stocks. The objectives of this study are to construct and utilize a system dynamics model of the depletion of a stock of natural aggregates due to pavement construction and maintenance, and determine the effect of using local and nonlocal aggregates, recycling and project cancellation (slowing growth) on the paving of roads. Long-term simulations are carried out with available aggregate stock, trucking distance and cost data. The quality of roads and a sustainability score, based on engineering, economic and environmental factors (emissions) are evaluated for different scenarios. An optimal combination of the use of local and nonlocal recycled aggregates, recycling and project cancellation is recommended. The proposed system dynamics model could be utilized by agencies to plan for the proper utilization of aggregate resources for road development and maintenance/rehabilitation projects.     

崇明生态岛建设解析

崇明岛是位于长江口、世界上面积最大的河口冲积岛。笔者构建了科学性与可操作性、现实性与前瞻性、针对性与示范性相结合的生态岛建设指标体系,并在崇明世界级生态岛建设中发挥了“引领生态岛建设方向,规范建设行为,调控建设进程”的作用,崇明生态岛建设成效初显。为了进一步发挥崇明生态岛建设的示范作用,笔者还提出了建设生态文明特区等建议。     

重庆市区城市建设用地预测研究

重庆市作为西部唯一的中央直辖市和长江上游地区最大的经济、文化、商贸中心,在西部大开发中扮演十分重要的角色。重庆市是一个典型的山地丘陵城市,地形起伏大,工程地质条件复杂,施工难度大而且建设费用高,极大地限制了重庆市城市建设的发展。再加上受以前城市建设政策的影响,重庆市的城市建设发展缓慢。城市建设用地长期不足。为此必须加快重庆市城市建设步伐,重点放在搞好城市建设规划,加强城市基础设施建设上。首先要做好城市建设用地预测,以便为规划提供科学依据。从重庆市城市建设用地的实际情况出发,采用目前应用广泛的灰色系统分析法GM(1．1)预测了重庆市区城市非农业人口规模,进而测算出城市人口规模,并根据几种可能的人均用地水平预测了未来重庆市区城市建设用地规模。     

大兴安岭森林火灾中居民避难行动的调查

本文利用民意测验的方法,通过对大兴安岭特大森林火灾中居民避难行动的调查,对重大灾害发生后避难系统工程进行了探讨,并分别对该工程进行了评价。     

安全系统思想

全国各类意外伤亡事故频发 ,安全生产形势十分严峻。安全生产的目的就是要预防和控制各类事故的发生 ,保护人民生命安全和社会财产安全。笔者认为 ,要做好安全生产工作 ,必须要有安全系统思想 ,运用系统工程的思想 ,去组织管理安全生产各个要素的发展变化 ,从而对事故进行预防和控制 ,安全生产系统是一个动态的系统工程。企业安全生产是一个大的系统链 ,这个链上的要素是很复杂的。安全系统归纳起来有三大子系统 ,即政府安全系统、企业安全系统、社会安全信息系统。子系统又由若干分系统组成 ,如安全管理系统、工艺安全系统等 ,每个分系统可建立自成体系的安全模型 ,将各自的安全要素统一在一个模型中 ,采用安全系统工程的方法 ,就可能预防和控制事故的发生。     

Operational Atmospheric Modeling System CARIS for Effective Emergency Response Associated with Hazardous Chemical Releases in Korea

The Chemical Accidents Response Information System (CARIS) was developed at the Center for Chemical Safety Management in South Korea in order to track and predict the dispersion of hazardous chemicals in the case of an accident or terrorist attack involving chemical companies. The main objective of CARIS is to facilitate an efficient emergency response to hazardous chemical accidents by rapidly providing key information in the decision-making process. In particular, the atmospheric modeling system implemented in CARIS, which is composed of a real-time numerical weather forecasting model and an air pollution dispersion model, can be used as a tool to forecast concentrations and to provide a wide range of assessments associated with various hazardous chemicals in real time.This article introduces the components of CARIS and describes its operational modeling system. Some examples of the operational modeling system and its use for emergency preparedness are presented and discussed. Finally, this article evaluates the current numerical weather prediction model for Korea.Published online     

Using system dynamics to model water-reallocation

Improving the efficiency of water allocation has long been recognised as a key problem for the water resources management decision-makers. However, assessing the efficacy of management decision is difficult due to the complexity and interconnectivity of water resource systems. For this reason, it is vital that robust modelling approaches are employed to deal with the feedback loops inherent in the water resource systems. Whilst many studies have applied modelling to various aspects of water resource management, little attention has been given to innovations in modelling approaches to deal with the modelling challenges associated with improving decision-making. The aim of this study is to apply a System Dynamics modelling approach to improve the efficiency of water allocation incorporating a myriad of irrigation system constraints. The system dynamic approach allows the different system components to be organised as a collection of discrete objects that incorporate data, structure and function to generate complex system behaviour. Through the application of a system dynamic approach, a robust model (named the Economical Reallocating Water Model (ERWM)) was developed which was used to examine the options of re-allocating water resources that minimize the water cost all over an irrigated agricultural area. The EWRM incorporated a wide range of complexities likely to be encountered in water resource management: surface and ground water sources, water trading between sources, system constraint such as maximum ground water pumping, rates, maximum possible trading volumes and differential water resource prices. Two hypothetical systems have been presented here as an example. The results show that the System Dynamics approach has a significant advantages in estimating and assessing the outcomes of alternative water management strategies through time and space.     

区域土地资源利用管理信息系统设计与应用——以长江三角洲无锡市滨湖区为例

区域土地资源利用管理信息系统是一种存储、兼容、管理、分析、显示与应用土地信息的计算机监控系统，是建立在地理信息系统（GIS）软件工具之上，并在ComGIS组件Mapobject2．0平台支撑下进行设计和开发应用的。该系统的设计与开发可为区域土地资源合理开发利用规划与产业布局的调整提供科学依据，特别是对高强度开发下的长江三角洲土地资源的可持续利用具有较重要的实际应用价值。     

浅谈ITS技术在危险化学品公路运输过程中的应用

公路运输已成为危险化学品运输的主要方式之一,但危险化学品在公路运输过程中由于不确定因素的存在,导致事故频发,已受到国人的广泛重视。智能交通运输系统(ITS)的应用,大大地削弱或消除了以往诱发交通事故的不安全因素。如将该系统用于危险品公路运输过程中,也能有效地预防并减少化学事故的发生。在此基础上,笔者提出由安全运输管理层、基础设施层、共用信息层、增值服务层组成的危险化学品公路运输安全智能化管理系统,研究了危险化学品公路运输安全智能化管理系统的框架,讨论了ITS技术在危化品公路运输过程中的应用并提出相应的解决方案     

22家企业建立职业健康安全管理体系前后社会和经济效益对比分析

作者抽取已建职业健康安全管理体系的22家企业,对其建立体系前后的企业经营活动、安全生产投入、因事故和职业病的经济投入(损失)进行分析.分析结果表明职业健康安全管理体系的建立和运行对企业有良好的社会和经济效益.