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711.
应用英国CRTN88模式和GIS进行道路交通噪声预测与规划   总被引:9,自引:0,他引:9  
介绍了一种将道路交通噪声预测模式CRTN88和地理信息系统(GIS)结合的方法及基本框架。实例研究证明,应用该方法所开发的系统能为道路交通噪声的实时预测和规划提供方便、高效的工具。并探讨了提高系统的实用性、集成度和预测精度的两点需要深入研究的问题。  相似文献   
712.
连云港市水环境整治规划研究   总被引:3,自引:0,他引:3  
本文在“控源导流”思想的指导下,根据连云港市水环境污染现状,提出了连云港市水环境整治规划方案,它包括蔷薇河水源保护工程、新沂河污水资源化生态工程、市区(新海地区)污水治理工程、石梁河水库水源保护工程和四县城区污水治理工程五大工程,试图根治连云港市水污染。  相似文献   
713.
Effects of Road Fencing on Population Persistence   总被引:6,自引:0,他引:6  
Abstract:  Roads affect animal populations in three adverse ways. They act as barriers to movement, enhance mortality due to collisions with vehicles, and reduce the amount and quality of habitat. Putting fences along roads removes the problem of road mortality but increases the barrier effect. We studied this trade-off through a stochastic, spatially explicit, individual-based model of population dynamics. We investigated the conditions under which fences reduce the impact of roads on population persistence. Our results showed that a fence may or may not reduce the effect of the road on population persistence, depending on the degree of road avoidance by the animal and the probability that an animal that enters the road is killed by a vehicle. Our model predicted a lower value of traffic mortality below which a fence was always harmful and an upper value of traffic mortality above which a fence was always beneficial. Between these two values the suitability of fences depended on the degree of road avoidance. Fences were more likely to be beneficial the lower the degree of road avoidance and the higher the probability of an animal being killed on the road. We recommend the use of fences when traffic is so high that animals almost never succeed in their attempts to cross the road or the population of the species of concern is declining and high traffic mortality is known to contribute to the decline. We discourage the use of fences when population size is stable or increasing or if the animals need access to resources on both sides of the road, unless fences are used in combination with wildlife crossing structures. In many cases, the use of fences may be beneficial as an interim measure until more permanent measures are implemented.  相似文献   
714.
Objective: Powered mobility devices (PMDs) are commonly used as aids for older people and people with disabilities, subgroups of vulnarable road users (VRUs) who are rarely noted in traffic safety contexts. However, the problem of accidents involving PMD drivers has been reported in many countries where these vehicles have become increasingly popular.

The aim of this study is to extract and analyze national PMD-related accident and injury data reported to the Swedish Traffic Accident Data Acquisition (STRADA) database. The results will provide valuable insight into the risks and obstacles that PMD drivers are exposed to in the traffic environment and may contribute to improving the mobility of this group in the long term.

Methods: The current study is based on data from 743 accidents and 998 persons. An analysis was performed on a subset of data (N?=?301) in order to investigate the development of accidents over a period of 10 years. Thereafter, each accident in the whole data set was registered as either single (N?=?427) or collision (N?=?315).

Results: The results show that there was a 3-fold increase in the number of PMD-related accidents reported to STRADA during the period 2007–2016.

With regard to single accidents, collisions, as well as fatalities, the injury statistics were dominated by males. Single accidents were more common than collisions (N?=?427 and N?=?316, respectively) and the level of injury sustained in each type of accident is on par.

The vast majority of single accidents resulted in the PMD driver impacting the ground (87%), due to either PMD turnover (71%) or the driver falling out of the PMD (16%). The reason for many of the single accidents was a difference in ground level (34%, typically a curb).

Cars, trucks, or buses were involved in 67% of collision events; these occured predominantly at junctions or intersections (70%).

Abbreviated Injury Scale (AIS) 3+ injuries were dominated by hip and head injuries in both single accidents and collision events.

Conclusions: The present study shows that further research on PMD accidents is required, with regard to both single accidents and collision events. To ensure that appropriate decisions are made, future work should follow up on injury trends and further improve the quality of PDM-related accident data. Improved vehicle stability and design, increased usage of safety equipment, proper training programs, effective maintenance services, and development of a supporting infrastructure would contribute to increased safety for PMD drivers.  相似文献   
715.
考虑到我国公路路线设计规范中停车视距计算未涉及弯道参数及路面凝冰引起的路面摩阻系数降低等严重危害车辆行驶安全的因素,以AASHTO模型为基础,通过分析弯道路段车辆行驶时的受力、路面摩阻系数、超高、圆曲线半径等因素推导了凝冰路面弯道路段停车视距计算模型,得出了最不利情况下凝冰路面弯道路段停车视距参考值。当路面发生凝冰现象时,若车辆以交通安全法规规定的冰雪路面最高车速30 km/h行驶,通过对比该行驶速度下凝冰路面弯道路段停车视距与我国规范规定的停车视距可知,没有发挥道路的最大通行能力。以现有道路设计采用的停车视距反算出在役路面发生凝冰现象时的安全行车控制速度,为凝冰路面弯道路段车辆安全行驶控制提供参考。  相似文献   
716.
ABSTRACT: This paper addresses the recent interest in management of the Missouri River. Interstate issues in the river basin include interbasin water diversions, riverbed and shoreline degradation, loss of recreational and natural areas, reduction in navigation capacity, the status of the Pick-Sloan Missouri Basin Program in terms of general river development, and the elimination of river basin commissions, An attempt to develop a comprehensive interstate water compact failed in the 1950s. The new efforts towards establishing a compact are discussed, as well as other available mechanisms for resolution of the current political and legal differences among the ten river basin states.  相似文献   
717.
ABSTRACT: Biophysical and socioeconomic effects are identified in reservoir, downstream, division channel, and receiving water body areas. Overall, the projects have been socially useful, especially from the perspective of hydroelectric, log driving, and economic development benefits. However selected socially inequitable aspects of the projects and other problems related to erosion, turbidity, multiple resource use, failure to clear trees, and heritage resource losses are identified. Suggestions for planning similar projects are presented.  相似文献   
718.
A methodology is described that allows determination of instream flow requirements for maintenance of riparian trees. Tree-ring data revealed strong relationships between tree growth and stream flow volume for riparian species at Rush Creek, an alluvial stream within an arid setting; these relationships allowed development of models that predict growth rates from hydrologic variables. The models can be used to assess instream flow requirements under the assumption that certain levels of growth are necessary to maintain the population. There is a critical need for development and use of instream flow methodologies for riparian vegetation, since present methodologies focus on needs of aquatic animals (e.g., fish) and may underestimate needs of the entire riparian ecosystem.  相似文献   
719.
交通是发展国民经济的先行官,为了适应我国改革开放的经济形势,改变长期落后的交通状况,公路建设需要超前发展。我国人口众多,土地资源贫乏,在发展公路建设的同时,必须尽可能节约土地,保护耕地资源。本文着重介绍了在高等级公路建设中,保护耕地的一些成功经验和建议。  相似文献   
720.
平顶山市区道路交通噪声污染现状与防治   总被引:6,自引:0,他引:6  
对平顶山市区道路交通噪声污染现状进行了调查,分析了市区道路交通噪声产生的原因和污染特点,提出了市区道路交通噪声的有关防治措施。  相似文献   
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