A cost estimate is one of the most important steps in road project management. There are ranges of factors that mostly affect the final project cost. Many approaches were used to estimate project cost, which took into...A cost estimate is one of the most important steps in road project management. There are ranges of factors that mostly affect the final project cost. Many approaches were used to estimate project cost, which took into consideration probable project performance and risks. The aim is to improve the ability of construction managers to predict a parametric cost estimate for road projects using SVM (support vector machine). The work is based on collecting historical road executed cases. The 12 factors were identified to be the most important factors affecting the cost-estimating model. A total of 70 case studies from historical data were divided randomly into three sets: training set includes 60 cases, cross validation set includes three cases and testing set includes seven cases. The built model was successfully able to predict project cost to the AP (accuracy performance) of 95%.展开更多
Awareness of the adverse ecological effects of road and other large construction projects has resulted in a rapidly growing demand to quantitatively predict and evaluate the effects on gene flow among plants and anima...Awareness of the adverse ecological effects of road and other large construction projects has resulted in a rapidly growing demand to quantitatively predict and evaluate the effects on gene flow among plants and animals in natural habitats.In this study,we evaluated the effects of different road construction scenarios on animal species movement by using the methods of ecological landscape connectivity in the typical regions of Yunnan Province,China.The results showed landscape connectivity levels(Probability of Connectivity(PC))decreased after road construction and species with lower dispersal abilities were more affected to the subsequent habitat fragmentation.First level roads affected landscape connectivity most significantly.At a distance of 100 m,the PC index decreased more than 50%.Further analysis suggested that the use of landscape connectivity to assess landscape processes revealed the adverse effects on the species movement more effectively compared with the traditional landscape pattern analysis.In addition,we conducted a graph theory and a least-cost modeling discussion,it is obvious that they are powerful tools to represent and analyze landscape networks with respect to related species movement.Network analysis offers a quantitative and simple but effective tool for ecological process assessment and biological conservation on large scales.展开更多
The Shanghai Cooperation Organization(SCO)was formed in 2001 after breakdown of the socialist system and the Soviet Union as a new form of cooperation between former socialist countries in Eurasian region.Mongolia joi...The Shanghai Cooperation Organization(SCO)was formed in 2001 after breakdown of the socialist system and the Soviet Union as a new form of cooperation between former socialist countries in Eurasian region.Mongolia joined the SCO in 2005 with an observer member status.Since 2007,Presidents of Mongolia began to participate every year to the Summit of the heads of SCO member states.By the initiative of Mongolian President,in 2014 the tripartite format of the meetings of the leaders of three countries:Russia,China,and Mongolia were established.In June 2016,during the third meeting of the leaders of Russia,China,and Mongolia in Tashkent(Uzbekistan),“The Russia-China-Mongolia Economic Corridor Program”document was signed.This program is aiming to develop the infrastructure of three countries,ensuring the competitiveness of products on the world market,and strengthening the Eurasian integration.The content of this program is combining the main ideas of Chinese“Belt-Road”megaproject,Russian initiative for developing of Eurasian economic integration and Mongolian“Steppe Road”project.The main goal of the“Steppe Road”initiative is to involve Mongolia to become the transit territory for transportation of natural gas,oil,and other products between Russia and China.In conclusion,the author gives some comments regarding the issue of full membership status of Mongolia to the international organization—SCO.展开更多
Drivers experience variations in travel time due to congestion and delays associated with road construction projects on existing transportation facilities. The effect on the travel time of a link decreases as its dist...Drivers experience variations in travel time due to congestion and delays associated with road construction projects on existing transportation facilities. The effect on the travel time of a link decreases as its distance from the road construction project increases. In addition, the effect could extend to the connecting arterial street links within the vicinity of the road construction project. Therefore, the focus of this research is to model the effect of a road construction project on the freeway and connecting arterial street link-level travel times. Data pertaining to a resurfacing construction project, which lasted for six months,was gathered from the traffic incident management systems(TIMS). The travel time data was collected and processed, for each selected freeway and connecting arterial street link,for six months before the start of the resurfacing construction project and six months during the construction of the resurfacing project. Generalized linear models(GLM) were developed and validated for before and during the construction project periods with the average travel time on a link as the dependent variable. Data such as time-of-the-day, dayof-the-week, the distance of a link from the work zone, subject link characteristics, and upstream and downstream link characteristics were collected and used as the predictor variables. The results indicate that the subject link, upstream link and downstream link characteristics have a significant effect on the freeway and connecting arterial street linklevel travel times due to the resurfacing construction project.展开更多
文摘A cost estimate is one of the most important steps in road project management. There are ranges of factors that mostly affect the final project cost. Many approaches were used to estimate project cost, which took into consideration probable project performance and risks. The aim is to improve the ability of construction managers to predict a parametric cost estimate for road projects using SVM (support vector machine). The work is based on collecting historical road executed cases. The 12 factors were identified to be the most important factors affecting the cost-estimating model. A total of 70 case studies from historical data were divided randomly into three sets: training set includes 60 cases, cross validation set includes three cases and testing set includes seven cases. The built model was successfully able to predict project cost to the AP (accuracy performance) of 95%.
基金Under the auspices of Nonprofit Environment Protection Specific Project of China(No.201209029-4)
文摘Awareness of the adverse ecological effects of road and other large construction projects has resulted in a rapidly growing demand to quantitatively predict and evaluate the effects on gene flow among plants and animals in natural habitats.In this study,we evaluated the effects of different road construction scenarios on animal species movement by using the methods of ecological landscape connectivity in the typical regions of Yunnan Province,China.The results showed landscape connectivity levels(Probability of Connectivity(PC))decreased after road construction and species with lower dispersal abilities were more affected to the subsequent habitat fragmentation.First level roads affected landscape connectivity most significantly.At a distance of 100 m,the PC index decreased more than 50%.Further analysis suggested that the use of landscape connectivity to assess landscape processes revealed the adverse effects on the species movement more effectively compared with the traditional landscape pattern analysis.In addition,we conducted a graph theory and a least-cost modeling discussion,it is obvious that they are powerful tools to represent and analyze landscape networks with respect to related species movement.Network analysis offers a quantitative and simple but effective tool for ecological process assessment and biological conservation on large scales.
文摘The Shanghai Cooperation Organization(SCO)was formed in 2001 after breakdown of the socialist system and the Soviet Union as a new form of cooperation between former socialist countries in Eurasian region.Mongolia joined the SCO in 2005 with an observer member status.Since 2007,Presidents of Mongolia began to participate every year to the Summit of the heads of SCO member states.By the initiative of Mongolian President,in 2014 the tripartite format of the meetings of the leaders of three countries:Russia,China,and Mongolia were established.In June 2016,during the third meeting of the leaders of Russia,China,and Mongolia in Tashkent(Uzbekistan),“The Russia-China-Mongolia Economic Corridor Program”document was signed.This program is aiming to develop the infrastructure of three countries,ensuring the competitiveness of products on the world market,and strengthening the Eurasian integration.The content of this program is combining the main ideas of Chinese“Belt-Road”megaproject,Russian initiative for developing of Eurasian economic integration and Mongolian“Steppe Road”project.The main goal of the“Steppe Road”initiative is to involve Mongolia to become the transit territory for transportation of natural gas,oil,and other products between Russia and China.In conclusion,the author gives some comments regarding the issue of full membership status of Mongolia to the international organization—SCO.
基金funded by the United States Department of Transportation-Office of the Assistant Secretary for Research and Technology (USDOT/OST-R) University Transportation Centers Program (Grant #69A3551747127)。
文摘Drivers experience variations in travel time due to congestion and delays associated with road construction projects on existing transportation facilities. The effect on the travel time of a link decreases as its distance from the road construction project increases. In addition, the effect could extend to the connecting arterial street links within the vicinity of the road construction project. Therefore, the focus of this research is to model the effect of a road construction project on the freeway and connecting arterial street link-level travel times. Data pertaining to a resurfacing construction project, which lasted for six months,was gathered from the traffic incident management systems(TIMS). The travel time data was collected and processed, for each selected freeway and connecting arterial street link,for six months before the start of the resurfacing construction project and six months during the construction of the resurfacing project. Generalized linear models(GLM) were developed and validated for before and during the construction project periods with the average travel time on a link as the dependent variable. Data such as time-of-the-day, dayof-the-week, the distance of a link from the work zone, subject link characteristics, and upstream and downstream link characteristics were collected and used as the predictor variables. The results indicate that the subject link, upstream link and downstream link characteristics have a significant effect on the freeway and connecting arterial street linklevel travel times due to the resurfacing construction project.