• Title/Summary/Keyword: Light Pollution

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Evaluations for Representativeness of Light-Duty Diesel Vehicles' Fuel-based Emission Factors on Vehicle Operating Conditions (연료 소비량에 기반한 소형 경유차 대기오염물질 배출계수의 운전조건별 대표성 평가)

  • Lee, Taewoo;Kwon, Sangil;Son, Jihwan;Kim, Jiyoung;Jeon, Sangzin;Kim, Jeongsoo;Choi, Kwangho
    • Journal of Korean Society for Atmospheric Environment
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    • v.29 no.6
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    • pp.745-756
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    • 2013
  • The purpose of this study is to evaluate representativeness of fuel-based emission factors. Twelve light-duty diesel vehicles which meet Euro-3 to 5 legislative emission limits were selected for emission tests. Second-by-second modal emission rates of vehicles were measured on a standard laboratory chassis dynamometer system. An off-cycle driving cycle was developed as a representative Korean real-world on-road driving cycle. Fuel-based emission factors were developed for short trip segments that involved in the selected driving cycle. Each segment was defined to have unit travel distance, which is 1 km, and characterized by its average speed and Relative Positive Acceleration (RPA). Fuel-based $NO_x$ emission factors demonstrate relatively good representativeness in terms of vehicle operation conditions. $NO_x$ emission factors are estimated to be within ${\pm}20%$ of area-wide emission factor under more than 40% of total driving situations. This result implies that the fuel-based $NO_x$ emission factor could be practically implemented into the on-road emission management strategies, such as a remote sensing device (RSD). High emitting vehicles as well as high emitting operating conditions heavily affect on the mean values and distributions of CO and THC emission factors. Few high emitting conditions are pulling up the mean value and biasing the distributions, which weaken representativeness of fuel-based CO and THC emission factors.

A Study on Aspheric Optics European LED Streetlights Type for the Prevention of Light Pollution (빛 공해 방지를 위한 유럽형 LED 가로등용 비구면 광학계에 관한 연구)

  • Lee, Shi-Woo;Lee, Chang-Soo;Hyun, Dong-Hoon
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.22 no.3
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    • pp.429-436
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    • 2013
  • In this study, we researched a pendant-type aspherical optical system, which could be applied to street lighting and security lighting in Europe. The goal of this research was eco-friendly artificial lighting that could be used for the one-to-one replacement of ordinary lighting. LED lighting was miniaturized by using one COB LED Module and one aspherical optical system, which could control the luminosity of the LED. Through the aspherical optical system, the light distribution angle could be controlled in a range of $140^{\circ}$ for the X-axis and $40^{\circ}$ for the Y-axis. This means that this optical system is appropriate for catenary-type lighting, which is widely used in Europe on both narrow and broad roads. The performance was determined using a lighting simulation program. This lighting system simulation showed that road rates M4 and M5 could be satisfied, with the condition of a 13-m height and 50-m distance (U0 and TI). The simulation program estimated that light pollution, which disturbs sleep, could beeliminated in the European streetlight case. Determining methods for the light distribution control, performance, and optimal lighting setup conditions is very important to prevent light pollution. Moreover, the initial step of developing the lighting system design and post management will require an effort with much analysis.

High Incidence of Breast Cancer in Light-Polluted Areas with Spatial Effects in Korea

  • Kim, Yun Jeong;Park, Man Sik;Lee, Eunil;Choi, Jae Wook
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.1
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    • pp.361-367
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    • 2016
  • We have reported a high prevalence of breast cancer in light-polluted areas in Korea. However, it is necessary to analyze the spatial effects of light polluted areas on breast cancer because light pollution levels are correlated with region proximity to central urbanized areas in studied cities. In this study, we applied a spatial regression method (an intrinsic conditional autoregressive [iCAR] model) to analyze the relationship between the incidence of breast cancer and artificial light at night (ALAN) levels in 25 regions including central city, urbanized, and rural areas. By Poisson regression analysis, there was a significant correlation between ALAN, alcohol consumption rates, and the incidence of breast cancer. We also found significant spatial effects between ALAN and the incidence of breast cancer, with an increase in the deviance information criterion (DIC) from 374.3 to 348.6 and an increase in $R^2$ from 0.574 to 0.667. Therefore, spatial analysis (an iCAR model) is more appropriate for assessing ALAN effects on breast cancer. To our knowledge, this study is the first to show spatial effects of light pollution on breast cancer, despite the limitations of an ecological study. We suggest that a decrease in ALAN could reduce breast cancer more than expected because of spatial effects.

Comparison of Correlation between CVS-75 Mode and Korea Mode to Estimate Emission Factors from Vehicles (자동차 오염물질 배출계수 산정을 위한 CVS-75모드와 국내차속모드의 상관성 비교 연구)

  • Jung, Sung-Woon;Ryu, Jeong-Ho;Lyu, Young-Sook
    • Journal of Korean Society for Atmospheric Environment
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    • v.22 no.3
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    • pp.383-391
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    • 2006
  • In Korea, the major source of serious air pollution is motor vehicles. Air pollution from vehicles has been annually increased. Then the government will try to control the vehicle emission by applying the effective emission management policy for the manufactured and in-used car. It is necessary to correctly calculate the emission factor for successful propulsion of the vehicle emission control policy. In this study, correlation analysis of exhaust emissions from vehicles between CVS-75 mode and Korea mode was conducted. A total of 25 light-duty buses were tested on the chassis dynamometer system in order to measure CO, HC, NOx PM and fuel efficiency (F.E.). For the test modes, 10 different Korea modes and CVS-75 mode were used. As the result of correlation analysis between those modes, most of the correlation coefficients were higher than 0.90. On the basis of high correlation between those modes, correction factors by driving conditions were estimated. Through the results of this study, we obtained essential basic data to correct difference from those modes.

Analysis of Factors That Cause Light Pollution in Islands in Dadohaehaesang National Park (다도해해상국립공원 내 섬 지역의 빛공해 유발 요인 분석)

  • Sung, Chan Yong
    • Korean Journal of Environment and Ecology
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    • v.36 no.4
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    • pp.433-441
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    • 2022
  • Light pollution is one of the factors that disturb coastal and island ecosystems. This study examined the factors causing light pollution in the islands in Daedohaehaesang National Park using nighttime satellite images. This study selected 101 islands with an area of 100,000 m2 or more in Daedohaehaesang National Park, and measured the levels of light pollution of the selected islands by calculating mean nighttime radiance recorded in VIIRS DNB monthly images for January, April, August, and October 2019. Of seven districts of the park, The highest mean nighttime radiance was recorded in Geumodo district (17,666nW/m2/sr), followed by Geonumdo·Baekdo, Narodo, Soando·Cheongsando districts. By season, mean nighttime radiance in October was the highest at 9,509nW/m2/sr, followed by August, January, and April. Regression analyses show that the total floor area and the number of lighthouses in a 5 km buffer area had a statistically significant effect on mean nighttime radiance at all times, but those within the island did not, indicating that light pollution in islands in a national park where land development is strictly restricted is influenced by artificial lights in nearby areas. However, the total floor area of an island significantly affected mean nighttime radiance only in August, which appears to be attributed to the impact of intensive use of artificial light by visitors during summer vacation. The size of an island had a negative (-) effect on nighttime radiance. This negative effect suggests that light pollution is a type of ecological edge effect, i.e., the smaller island is more likely to have a relatively larger proportion of edge area that is affected by light emitted from the neighboring areas. The results of this study indicate that managing artificial lights in nearby areas is necessary to mitigate light pollution in islands in marine and coastal national parks.

A Study on the Development Strategies for the Light Rail Transit Industry (경전철 산업 발전방안 연구)

  • Chung Kyung-Ryul;Yoon Se-Kyun;Choi Yong-Hoon
    • Proceedings of the KSR Conference
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    • 2005.11a
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    • pp.500-509
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    • 2005
  • Light-rail transit system has many characteristics of better accessibility. frequency service, low construction cost, reduced air pollution and medium-capacity public transport etc. Light rail transit system as a urban transportation system has been growing worldwide since the late 20th century. More than 300 cities around the world have light railway systems. Many medium-size cities in domestic site is planning the construction of light railway. This paper describes the development strategies for the light rail transit industry.

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Effects of Light Pollution and Environmental Factors on Dawn Song Initiation Time of Great Tit, Parus major (빛공해 및 환경요인에 의한 박새의 새벽 Song 시작시간 영향 연구)

  • Ki, Kyong-Seok;Cho, Woo
    • Korean Journal of Environment and Ecology
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    • v.28 no.4
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    • pp.411-418
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    • 2014
  • This study seeks to identify the effects of light pollution and environmental factors on Great Tits(Parus major) bird's chirping at dawn. For this research, the campus of Sanji University, Wonju, South Korea was selected as the area with light pollution and the western forest of the Chiaksan National Park was chosen as the natural area herein. The Recording period was between March 26th and May 30th, 2014. As a result of analyzing the chirping time according to light pollution, it was found that the light pollution area clearly showed earlier chirping time than the natural area (p<0.05). Great Tits(P. major) normally start their first chirping before sunrise and in most of the days under investigation of this research, those in Sanji University started to chirp earlier. This faster chirping time seems to improve the chance for the female birds to mate with immature males thus, baby birds hatch earlier than the appropriate breeding season and results in the lack of feed resources. The correlation between Great Tits'(P. major) dawn chirping and environmental factors were investigated herein including the time of sunrise, civil twilight, navigation twilight, astronomical twilight, average temperature, highest temperature, lowest temperature, time of moonrise and cloudiness. The first chirping time of wild birds in the day was found to have correlations with all of the environmental factors excluding the time of moonrise and cloudiness. Great Tits(P. major) started their first chirping before sunrise when the day started to break around civil twilight. Along with the earlier sunrise and higher air temperature, their dawn chirping time was also quickened. The time of moonrise and cloudiness did not show a correlation and further follow-up studies will be necessary in this regard.

Measure of Environmental Performance through Integrated Pollution Intensities (통합오염원단위 지수를 이용한 환경성과 측정)

  • Kang, Sang-Mok;Chung, Young-Keun;Cho, Joo-Hyun
    • Environmental and Resource Economics Review
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    • v.14 no.1
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    • pp.135-166
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    • 2005
  • This paper measures integrated pollution intensities and changes in pollution intensity, and figure out environmental performance. We introduce a new definition of pollution intensity and its method measuring integrated pollution intensities. We distinguish 24 manufacturing industries into light industry and heavy industry, and divide heavy industry into pollution industry and the other residual heavy industry to measure the integrated pollution intensities and their changes. While the pollution industry within heavy industry, based on the integrated pollution intensity, was the most pollution-intensive, the other residual heavy industry within the heavy industry was the most successive in reducing pollutants. The annualized average index of the integrated pollution intensities grew as much as 9.1 percent, of which the annualized change in the index of pollution emission increased 13.3 percent, but the improvement of 3.9 percent in the change of output quantity offset the increase in the index of pollution emission. The changes in the integrated pollution intensity for the light and heavy industries were 1.125 and 1.042, respectively. The reason the heavy industry showed the lower change in the index of pollution intensity, while the change in the pollution industry was very high, was because the average change in the other heavy industry decreased around 9 percent.

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A Study of Greenhouse Gas Emission Rates from LDTs according to Emission Certification Modes and Real-World Vehicle Driving Cycles in Korea (차량인증모드와 실도로 주행모드별 국내 경유 소형화물 자동차의 온실가스 배출특성 분석)

  • Kim, Ji Young;Seo, Chungyoul;Son, Jihwan;Park, Junhong;Moon, Taeyoung;Lee, Sangeun;Kim, Jeongsoo
    • Journal of Climate Change Research
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    • v.3 no.4
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    • pp.235-243
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    • 2012
  • Mobile sources are one of the most significant contributors to the inventory of greenhouse gas (GHG). The administration in Korea has set a goal of cutting GHG emissions of vehicles by 34.3% compared to Business As Usual (BAU) by 2020. To achieve this goal, GHG emission standards for vehicles have been applied since 2012, and now light-duty trucks are under consideration to be included to the vehicle types that will be regulated in the new version of GHG emission standards. Therefore, this study focuses on analyzing characteristics of exhaust GHGs (CO2, CH4, and N2O) emissions of diesel light-duty trucks according to their various driving modes. GHGs emissions of diesel light-duty trucks reduced in inverse proportion to the speed of the vehicles. GHGs emissions from the combined mode were 8% and 14% lower than those from the CVS- 75 and NEDC modes, respectively.

Environmental save of the Ondal cave and the management plan of an electric saving (온달동굴의 환경보존과 전기절약의 관리 방안)

  • Yoon, Jung-Mo
    • Journal of the Speleological Society of Korea
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    • no.88
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    • pp.26-30
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    • 2008
  • The black pollution that was able to include green pollution to appear for the intensity of light by an illumination institution is what after all I cannot ignore, and it may be said that chase thing damage by the isolation action that is white pollution done a long story in this outside a certain range by air quality change, dried present situation is really the environmental disruption by development and a damage phenomenon. If I am replaced in winker and I install a sensor light in the outlet by addition and use the electricity illumination that I installed for a tourist in the cave, it is expected that I can be available all the time that it is possible for electricity reduction more than the present and watches tourist passage plan private business Electric illumination in the cave for the environmental save in the cave because it is possible for more electricity reduction to be particularly off-season than on-season.