To measure the length of traffic queue, a vehicle motion model at intersections was built, and based on it the effective traffic queue was def＇med. Color images segmentation and frame differencing technique were used...To measure the length of traffic queue, a vehicle motion model at intersections was built, and based on it the effective traffic queue was def＇med. Color images segmentation and frame differencing technique were used to detect the foreground and the moving vehicles by detecting regions of the images, and then measure the length of effective traffic queue. By processing the image sequence acquired at certain intersection, the results prove that it is able to work out the traffic queue effectively by using the two techniques.展开更多
Air pollution monitoring is one of the most important features in contamination risk management.This is because many of the compounds contained within air pollution present a serious risk both for the preservation of ...Air pollution monitoring is one of the most important features in contamination risk management.This is because many of the compounds contained within air pollution present a serious risk both for the preservation of open air cultural heritage and for human health.New particle formation is a major contributor to urban pollution,but how it occurs in cities is often puzzling.As more and more people enjoy an increased quality of life through outdoor activity,managing outdoor air quality is vital.This study presents the application of a low-cost system for monitoring the current level of road traffic passengers’exposure to particulate air contamination.The global rise in tourism also leads to apprehension about its probable destructive influence on various aspects of global preservation.One of the major risks encountered by tourists,stemming from modes of transport,are nanoparticles(NPs)(<100 nm)and ultra-fine particles(UFPs)(100-1000 nm)consisting of potentially hazardous elements(PHEs).This study examines Steen Castle,a medieval fortress located in Antwerp,Belgium.Significant NPs with PHEs,were found in the air sampled in this area.The self-made passive sampler(LSPS)described in this study,consisting of retainers specially designed for advanced microscopic analysis,is used for the first time as a simple way to characterize the surrounding atmospheric contamination caused by NPs and UFPs,without the need of other commonly employed more expensive particulate focused active samplers such as cascade impactors.This study aims to assess the result of the utilization of a low-cost,LSPS,to determine outdoor NPs and UFPs in a Belgian urban(Steen Castle)and rural area(Fort van Schoten).This work is the first to detail the usefulness of LSPS for the evaluation of Belgium’s outdoor air for NPs and UFPs,which contain PHEs.展开更多
Noise surveys in this country reported that a large number of classrooms in primary and secondary schools in the urban areas were disturbed by environmental noise, particularly by traffic noise. A series of psychologi...Noise surveys in this country reported that a large number of classrooms in primary and secondary schools in the urban areas were disturbed by environmental noise, particularly by traffic noise. A series of psychological tests were conducted to identify pupils' behavior in a classroom under different noise levels within the range of 40 to 70 dBA. Statistical analysis results were obtained by using Relational Data Analysis System (RDAS) software. According to the t-test and single factor variance analysis of the results, significant differences of the pupils' behavior in the classroom have been observed when the percentile exceeded sound level either L50 exceeds 50 dBA or L10 exceeds 55 dBA, or the equivalent continuous sound level Leq exceeds 50 dBA. The same conclusion has been drawn from the average percentages of syllable articulation under different noise levels in a classroom which were the results of tests made in accordance with the procedure described in the National Standard. The maximum acceptable noise level in the classroom thus can be determined.展开更多
基金The Cultivation Fund of the Key Scientif-ic and Technical Innovation Project,Ministry of Education of China
文摘To measure the length of traffic queue, a vehicle motion model at intersections was built, and based on it the effective traffic queue was def＇med. Color images segmentation and frame differencing technique were used to detect the foreground and the moving vehicles by detecting regions of the images, and then measure the length of effective traffic queue. By processing the image sequence acquired at certain intersection, the results prove that it is able to work out the traffic queue effectively by using the two techniques.
基金funding received from the Brazilian National Council for Scientific and Technological Development(CNPq)the Administrative Department of Science,Technology,and Innovation of the Colombian Government(Colciencias)。
文摘Air pollution monitoring is one of the most important features in contamination risk management.This is because many of the compounds contained within air pollution present a serious risk both for the preservation of open air cultural heritage and for human health.New particle formation is a major contributor to urban pollution,but how it occurs in cities is often puzzling.As more and more people enjoy an increased quality of life through outdoor activity,managing outdoor air quality is vital.This study presents the application of a low-cost system for monitoring the current level of road traffic passengers’exposure to particulate air contamination.The global rise in tourism also leads to apprehension about its probable destructive influence on various aspects of global preservation.One of the major risks encountered by tourists,stemming from modes of transport,are nanoparticles(NPs)(<100 nm)and ultra-fine particles(UFPs)(100-1000 nm)consisting of potentially hazardous elements(PHEs).This study examines Steen Castle,a medieval fortress located in Antwerp,Belgium.Significant NPs with PHEs,were found in the air sampled in this area.The self-made passive sampler(LSPS)described in this study,consisting of retainers specially designed for advanced microscopic analysis,is used for the first time as a simple way to characterize the surrounding atmospheric contamination caused by NPs and UFPs,without the need of other commonly employed more expensive particulate focused active samplers such as cascade impactors.This study aims to assess the result of the utilization of a low-cost,LSPS,to determine outdoor NPs and UFPs in a Belgian urban(Steen Castle)and rural area(Fort van Schoten).This work is the first to detail the usefulness of LSPS for the evaluation of Belgium’s outdoor air for NPs and UFPs,which contain PHEs.
文摘Noise surveys in this country reported that a large number of classrooms in primary and secondary schools in the urban areas were disturbed by environmental noise, particularly by traffic noise. A series of psychological tests were conducted to identify pupils' behavior in a classroom under different noise levels within the range of 40 to 70 dBA. Statistical analysis results were obtained by using Relational Data Analysis System (RDAS) software. According to the t-test and single factor variance analysis of the results, significant differences of the pupils' behavior in the classroom have been observed when the percentile exceeded sound level either L50 exceeds 50 dBA or L10 exceeds 55 dBA, or the equivalent continuous sound level Leq exceeds 50 dBA. The same conclusion has been drawn from the average percentages of syllable articulation under different noise levels in a classroom which were the results of tests made in accordance with the procedure described in the National Standard. The maximum acceptable noise level in the classroom thus can be determined.
