高速公路改扩建作业区交通安全设施设置研究

根据高速公路改扩建施工区的交通特性及驾驶人的反应特征,将施工作业区划分为7个分段,构建驾驶人视认模型,并对各个分段安全设施进行设置,可保障高速公路施工作业区的安全与通畅,这已被郑洛高速公路所证实。     

Policy considerations for wetland wastewater treatment in the coastal zone: A case study for Louisiana

Two major environmental problems currently affecting the Louisiana coastal zone are a high rate of wetland loss and high levels of surface water pollution. The application of secondarily treated wastewater to wetlands can be a means of dealing with both of these problems. The benefits of wetland wastewater treatment include improved surface water quality, increased accretion rates to balance a high relative water level rise due mainly to subsidence, improved plant productivity and habitat quality, and decreased capital outlays for conventional engineering treatment systems. Wetland treatment systems can, therefore, be designed and operated to restore deteriorating wetlands. Hydrologically altered wetlands, which are common in the Louisiana coastal zone, are appropriate for receiving municipal and some types of industrial effluent. While the U.S. Environmental Protection Agency has determined wetland wastewater treatment is effective in treating municipal effluent, it has discouraged the use of natural wetlands for this purpose. At the same time, funds are being used for the construction of artificial wetlands to treat municipal effluent. In the Louisiana coastal zone, however, wetlands are deteriorating and disappearing due to hydrological alteration and a high rate of relative sea level rise. If no action is taken, these trends will continue. Effluent discharge to existing wetlands should be incorporated into a comprehensive management plan designed to increase sediment and nutrient input into subsiding wetlands in the Louisiana coastal zone, improve water quality, and result in more economical waste‐water treatment. The authors believe that the Louisiana example serves as a model for other coastal areas especially in light of projections of accelerated sea level rise.     

辽东山区预防土壤砂砾化的技术措施

简要介绍了辽东山区17万hm 2砂砾化山丘的现状,概述砂砾化山丘的类型、特点,并提出了植物措施、工程措施、封育措施等几种预防砂砾化山丘的技术措施。     

结合兰州彭家坪T210#路建设浅淡城市高坪地区道路选线

城市高坪地区通常存在区域交通不畅的问题,出口道路经常制约着城市高坪地区的经济、文化发展.该文结合兰州市彭家坪T210#路路线选择,总结了城市面上高坪地区选线的几点经验,可供道路专业人员参考.     

贵阳市西南环线二期总体方案

贵阳市西南环线二期位于城市中心区东南部,地形起伏大,属于旧路拓宽改建项目。针对项目特点,对总体思路、方案布置等方面进行了介绍,为类似山区城市道路方案研究提供参考。     

山区农村公路安全保障工程应用技术研究

在对山区农村公路广泛调研的基础上,针对事故多发路段,运用具有山区农村公路特色的安全保障技术,对不同危险路段综合安全保障工程的应用进行论述,提出相应的安全保障工程改善对策。     

天津滨海地区地铁工程耐久性影响因素分析

鉴于天津滨海地区地铁工程环境的复杂性和特殊性,对影响耐久性的氯离子侵蚀、硫酸盐侵蚀、杂散电流、碳化破坏和冻融破坏等主要外部工程环境因素进行了分析和阐述,主要分析了其成因、机理及现行规范中的相关规定等,为工程的耐久性设计、施工及运营提供参考借鉴。最后建议天津滨海地区地铁工程建设引入针对性的耐久性专题研究,以保证百年设计目标的顺利实现。     

双控道岔联系电路的设计与实现

在个别站场间,为节省占地面积或受其他因素制约,两站的联锁区是由一组双动道岔隔开。若其中一站为计算机联锁控制,另一站为6502电气集中控制,依据相关设计规范,设计出一套计算机联锁车站与6502电气集中车站利用渡线隔开时的结合电路。该结合电路安全可靠,未改变原有电路定型结构。经过联锁模拟实验,该设计方案合理可行。     

State ocean policy initiatives in Florida

Abstract

A territorial sea comprising 6.7 million acres of offshore lands extending three geographic miles into the Atlantic Ocean three marine leagues (nine geographic miles) into the Gulf of Mexico makes Florida the second largest “oceanowning”; state in the contiguous United States. Florida's history, climate, economic development, and worldwide reputation have evolved from the state's relationship with the sea. The state is now becoming aware that aggressive management of its ocean resources is necessary to preserve the future of that relationship. The purpose of this article is to present some of Florida's recent legal and policy initiatives that have been directed toward better understanding and management of ocean resources and uses.     

现场总线式调速控制系统的结构及原理

介绍现场总线式调速控制系统的结构及原理，分析了该系统的技术特点及性能指标。