Ensuring adequate access to truck parking is critical to the safe and efficient movement of freight traffic. There are strict federal guidelines for commercial truck driver rest periods. Rest areas and private truck s...Ensuring adequate access to truck parking is critical to the safe and efficient movement of freight traffic. There are strict federal guidelines for commercial truck driver rest periods. Rest areas and private truck stops are the only places for the trucks to stop legally and safely. In locations without sufficient parking areas, trucks often park on interstate ramps, which create safety risks for other interstate motorists. Historically, agencies have employed costly and time intensive manual counting methods, camera surveillance, and driver surveys to assess truck parking. Connected truck data, available in near real-time, offers an efficient alternative to practitioners to assess truck parking patterns and identify areas where there may be insufficient safe parking spaces. This paper presents a case study of interstate I-70 in east central Indiana and documents the observed spatiotemporal impacts of a rest area closure on truck parking on nearby interstate ramps. Results showed that there was a 28% increase in parking on ramps during the rest area closure. Analysis also found that ramps closest to the rest area were most impacted by the closure, seeing a rise in truck parking sessions as high as 2.7 times. Parking duration on the ramps during rest area closure also increased drastically. Although it was expected that this would result in increased parking by trucks on adjacent ramps, this before, during, after scenario provided an ideal scenario to evaluate the robustness of these techniques to assess changing parking characteristics of long-haul commercial trucks. The data analytics and visualization tools presented in this study are scalable nationwide and will aid stakeholders in informed data-driven decision making when allocating resources towards improving the nations commercial vehicle parking infrastructure.展开更多
Michoacán has a deforested area of 525,260 ha, representing 52,526 ha per year, mainly caused by anthropogenic disturbances such as agricultural burning and forest fires (50%), change of use of land for extensive...Michoacán has a deforested area of 525,260 ha, representing 52,526 ha per year, mainly caused by anthropogenic disturbances such as agricultural burning and forest fires (50%), change of use of land for extensive livestock farming (28%), agriculture (17%) and illegal logging (5%). The establishment of forest plantations is an alternative for reducing the pressure on natural forests and creating options for sustainable development and diversification of production and conversion of land for agricultural and livestock fragmented for forestry purposes. The aim of this study was to determine the potential areas for commercial forest plantations of Enterolobium cyclocarpum (Jacq.) Griseb. in the State of Michoacán, México, through the use of Geographic information systems (GIS). Areas were identified using IDRISI 32, and ArcView software. Screening variables include annual temperature, annual precipitation, land use, soil type, elevation and slope. Products obtained were field verified. Two maps where potential areas for the establishment of commercial forest plantations of E. cyclocarpum shown were obtained. Potential areas for commercial forest plantation establishment are (0% - 15% slope) for commercial forest plantations mechanized was 57,227 ha and (15% - 30% slope) for manual plantations was 6273 ha. The total area in the state with potential for the establishment of the species in the study was 63,500 ha.展开更多
The targeted area for plant reforestation in the state of Michoacan is made up of eroded areas and pasture induced areas, both adding to 525,260 ha and representing 10.9% of the total surface of the state. The regions...The targeted area for plant reforestation in the state of Michoacan is made up of eroded areas and pasture induced areas, both adding to 525,260 ha and representing 10.9% of the total surface of the state. The regions with the largest areas in need of reforestation are the Costa with 185,396 ha (29%), Oriente with 106,836 (17%) and Tierra Caliente with 96,284 (15%). Commercial forest plantations are an alternative for reducing the pressure on natural forests and creating options for sustainable and diversified development, changing the land use from fragmented agricultur and livestock purposes to forestry. The object of this study was to determine potential areas for the establishment of commercial forest plantations of Tabebuia rosea (Bertol.) DC. in the state of Michoacan, Mexico, by using geographic information systems. The outlining of potential areas was performed with the IDRISI 32 and ArcView programs, according to the environmental requirements of T. rosea. These environmental requirements include precipitation, temperature, soil, altitude, land use and slope. The analysis resulted in two maps where the potential areas for the establishment of commercial forest plantations with this species were shown, which turned out a total potential area of 54,320 ha, distributed in 47,566 ha considering a slope of 0% - 15% for non-manual forest plantations, and 6754 ha considering a slope of 15% - 30% for manual forest plantations. The ecologic conditions in Michoacan are favorable for successful establishment and development of commercial forest plantations of T. rosea.展开更多
The location pattern of different commercial stores in Shichahai, a historic conservation area in Beijing, was investigated from a street centrality perspective. Many previous studies have investigated the relationshi...The location pattern of different commercial stores in Shichahai, a historic conservation area in Beijing, was investigated from a street centrality perspective. Many previous studies have investigated the relationship between street centrality and land use patterns or commercial activities at interurban or intraurban scales. We considered Shichahai in this study to determine if street centrality applied at the street scale and if the street network was the only factor influencing the selection of store location. First, the nearest neighbor index, nearest neighbor hierarchical spatial cluster(NNHSC), and kernel density estimation(KDE) methods were used to provide baseline spatial distributions of commercial stores. Second, urban network analysis(UNA) tools were used to measure the street centrality indices under two conditions, with and without the weighting of cultural relics calculated by a principal component analysis(PCA). Finally, both store locations and centrality values at nodes were transformed to one unit(raster pixel) for a correlation analysis.The results showed that three of the four store types were clustered and had their own hotspots that were mostly located in the eastern and central parts of city blocks. The most momentous findings were determined from the street centrality indices. Among the three store types with correlation coefficients above 0.5, all centrality indices with landmark weighting, except straightness, had higher correlations,with closeness with landmark weighting having the highest correlation, followed by betweenness with landmark weighting. Therefore,we statistically concluded that street centrality could apply at the street scale and that the street network was not the only factor that influenced store location pattern, with landmarks also playing a significant role. The results provide guidance in determining the selection strategy for stores in a historic conservation area.展开更多
Due to the rapid urban construction, commercial districts in Beijing are constructed near subway stations. Good landscape greening plays a crucial role in improving the environmental quality of the area around subway ...Due to the rapid urban construction, commercial districts in Beijing are constructed near subway stations. Good landscape greening plays a crucial role in improving the environmental quality of the area around subway stations. At present, there are few studies on the landscape greening around subway stations adjacent to commercial districts. In this paper, field research on landscapes in the commercial district around seven typical subway stations was conducted to monitor real-time noise and crowd activities and analyze the utilization status of street parks, in order to provide a reference for the construction and renovation of the landscape greening around subway stations near commercial districts.展开更多
A study was conducted to identify the causes of low crop yield on a large scale commercial farm in Zimbabwe. Soil and water samples were collected from fields （0-60 cm） and the dam used for irrigation, respectively....A study was conducted to identify the causes of low crop yield on a large scale commercial farm in Zimbabwe. Soil and water samples were collected from fields （0-60 cm） and the dam used for irrigation, respectively. Soil samples were analysed for soil fertility characteristics while the water was analysed for irrigation quality. The soils on the farm were heavy, ranging from sand loams to sand clays and fertile （〉 40 mg kgl N and 〉 20 mg kg1 available P） indicating high fertilizer utilization. It was also noted that 50% of the fields on the farm had soil pH below 5.0 despite having high basic cation （Ca = 10-18 meq% and Mg = 4-7 meq%）. A similar trend was observed down the soil profile （30-60 cm）. The soil also had extremely high concentration of iron （〉 200 ppm）, manganese （〉 400 ppm） and sulphate （〉 4000 ppm）. These findings suggest that the extreme acidity under these soils is the outcome of the exposure of pyrite to moisture and air by tillage of the land. The water used for irrigation was established to be medium saline and alkaline （pH 〉 7.6）. This pyrite induced acidity could not be neutralised by the water from the dam and the high exchangeable bases in the soil. Such problems can possibly be managed by growing tolerant crops. Soil testing on commercial farms is vital for identifying such problems in commercial farms in Zimbabwe.展开更多
文摘Ensuring adequate access to truck parking is critical to the safe and efficient movement of freight traffic. There are strict federal guidelines for commercial truck driver rest periods. Rest areas and private truck stops are the only places for the trucks to stop legally and safely. In locations without sufficient parking areas, trucks often park on interstate ramps, which create safety risks for other interstate motorists. Historically, agencies have employed costly and time intensive manual counting methods, camera surveillance, and driver surveys to assess truck parking. Connected truck data, available in near real-time, offers an efficient alternative to practitioners to assess truck parking patterns and identify areas where there may be insufficient safe parking spaces. This paper presents a case study of interstate I-70 in east central Indiana and documents the observed spatiotemporal impacts of a rest area closure on truck parking on nearby interstate ramps. Results showed that there was a 28% increase in parking on ramps during the rest area closure. Analysis also found that ramps closest to the rest area were most impacted by the closure, seeing a rise in truck parking sessions as high as 2.7 times. Parking duration on the ramps during rest area closure also increased drastically. Although it was expected that this would result in increased parking by trucks on adjacent ramps, this before, during, after scenario provided an ideal scenario to evaluate the robustness of these techniques to assess changing parking characteristics of long-haul commercial trucks. The data analytics and visualization tools presented in this study are scalable nationwide and will aid stakeholders in informed data-driven decision making when allocating resources towards improving the nations commercial vehicle parking infrastructure.
文摘Michoacán has a deforested area of 525,260 ha, representing 52,526 ha per year, mainly caused by anthropogenic disturbances such as agricultural burning and forest fires (50%), change of use of land for extensive livestock farming (28%), agriculture (17%) and illegal logging (5%). The establishment of forest plantations is an alternative for reducing the pressure on natural forests and creating options for sustainable development and diversification of production and conversion of land for agricultural and livestock fragmented for forestry purposes. The aim of this study was to determine the potential areas for commercial forest plantations of Enterolobium cyclocarpum (Jacq.) Griseb. in the State of Michoacán, México, through the use of Geographic information systems (GIS). Areas were identified using IDRISI 32, and ArcView software. Screening variables include annual temperature, annual precipitation, land use, soil type, elevation and slope. Products obtained were field verified. Two maps where potential areas for the establishment of commercial forest plantations of E. cyclocarpum shown were obtained. Potential areas for commercial forest plantation establishment are (0% - 15% slope) for commercial forest plantations mechanized was 57,227 ha and (15% - 30% slope) for manual plantations was 6273 ha. The total area in the state with potential for the establishment of the species in the study was 63,500 ha.
文摘The targeted area for plant reforestation in the state of Michoacan is made up of eroded areas and pasture induced areas, both adding to 525,260 ha and representing 10.9% of the total surface of the state. The regions with the largest areas in need of reforestation are the Costa with 185,396 ha (29%), Oriente with 106,836 (17%) and Tierra Caliente with 96,284 (15%). Commercial forest plantations are an alternative for reducing the pressure on natural forests and creating options for sustainable and diversified development, changing the land use from fragmented agricultur and livestock purposes to forestry. The object of this study was to determine potential areas for the establishment of commercial forest plantations of Tabebuia rosea (Bertol.) DC. in the state of Michoacan, Mexico, by using geographic information systems. The outlining of potential areas was performed with the IDRISI 32 and ArcView programs, according to the environmental requirements of T. rosea. These environmental requirements include precipitation, temperature, soil, altitude, land use and slope. The analysis resulted in two maps where the potential areas for the establishment of commercial forest plantations with this species were shown, which turned out a total potential area of 54,320 ha, distributed in 47,566 ha considering a slope of 0% - 15% for non-manual forest plantations, and 6754 ha considering a slope of 15% - 30% for manual forest plantations. The ecologic conditions in Michoacan are favorable for successful establishment and development of commercial forest plantations of T. rosea.
基金Under the auspices of National Natural Science Foundation of China(No.51478007,51178016)Project of Fundamental Research of Chinese Cultural Heritage Research Institute(No.2016-JBKY-08)
文摘The location pattern of different commercial stores in Shichahai, a historic conservation area in Beijing, was investigated from a street centrality perspective. Many previous studies have investigated the relationship between street centrality and land use patterns or commercial activities at interurban or intraurban scales. We considered Shichahai in this study to determine if street centrality applied at the street scale and if the street network was the only factor influencing the selection of store location. First, the nearest neighbor index, nearest neighbor hierarchical spatial cluster(NNHSC), and kernel density estimation(KDE) methods were used to provide baseline spatial distributions of commercial stores. Second, urban network analysis(UNA) tools were used to measure the street centrality indices under two conditions, with and without the weighting of cultural relics calculated by a principal component analysis(PCA). Finally, both store locations and centrality values at nodes were transformed to one unit(raster pixel) for a correlation analysis.The results showed that three of the four store types were clustered and had their own hotspots that were mostly located in the eastern and central parts of city blocks. The most momentous findings were determined from the street centrality indices. Among the three store types with correlation coefficients above 0.5, all centrality indices with landmark weighting, except straightness, had higher correlations,with closeness with landmark weighting having the highest correlation, followed by betweenness with landmark weighting. Therefore,we statistically concluded that street centrality could apply at the street scale and that the street network was not the only factor that influenced store location pattern, with landmarks also playing a significant role. The results provide guidance in determining the selection strategy for stores in a historic conservation area.
基金Sponsored by National Natural Science Foundation of China(51508004)Science and Technology Plans of Ministry of Housing and Urban-Rural Development of the People’s Republic of China,Opening Projects of Beijing Advanced Innovation Center for Future Urban Design,Beijing University of Civil Engineering,Architecture(UDC2017030712)+1 种基金2018 Beijing Municipal University Academic Human Resources Development-Youth Talent Support Program(PXM2018_014212_000043)North China University of Technology "YuYOU" Talent Training Program
文摘Due to the rapid urban construction, commercial districts in Beijing are constructed near subway stations. Good landscape greening plays a crucial role in improving the environmental quality of the area around subway stations. At present, there are few studies on the landscape greening around subway stations adjacent to commercial districts. In this paper, field research on landscapes in the commercial district around seven typical subway stations was conducted to monitor real-time noise and crowd activities and analyze the utilization status of street parks, in order to provide a reference for the construction and renovation of the landscape greening around subway stations near commercial districts.
文摘A study was conducted to identify the causes of low crop yield on a large scale commercial farm in Zimbabwe. Soil and water samples were collected from fields （0-60 cm） and the dam used for irrigation, respectively. Soil samples were analysed for soil fertility characteristics while the water was analysed for irrigation quality. The soils on the farm were heavy, ranging from sand loams to sand clays and fertile （〉 40 mg kgl N and 〉 20 mg kg1 available P） indicating high fertilizer utilization. It was also noted that 50% of the fields on the farm had soil pH below 5.0 despite having high basic cation （Ca = 10-18 meq% and Mg = 4-7 meq%）. A similar trend was observed down the soil profile （30-60 cm）. The soil also had extremely high concentration of iron （〉 200 ppm）, manganese （〉 400 ppm） and sulphate （〉 4000 ppm）. These findings suggest that the extreme acidity under these soils is the outcome of the exposure of pyrite to moisture and air by tillage of the land. The water used for irrigation was established to be medium saline and alkaline （pH 〉 7.6）. This pyrite induced acidity could not be neutralised by the water from the dam and the high exchangeable bases in the soil. Such problems can possibly be managed by growing tolerant crops. Soil testing on commercial farms is vital for identifying such problems in commercial farms in Zimbabwe.
