• Title/Summary/Keyword: pollution level

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A Study on Network Based Traffic Signal Optimization Using Traffic Prediction Data (교통예측자료 기반 Network 차원의 신호제어 최적화 방안)

  • Han, Jeong-hye;Lee, Seon-Ha;Cheon, Choon-Keun;Oh, Tae-ho;Kim, Eun-Ji
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.14 no.6
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    • pp.77-90
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    • 2015
  • An increasing number of vehicles is causing various traffic problems such as chronic congestion of highways and air pollution. Local governments have been managing traffic by constructing systems such as Intelligent Transport Systems (ITS) and Advanced Traffic Management Systems (ATMS) to relieve such problems, but construction of an infrastructure-based traffic system is insufficient in resolving chronic traffic problems. A more sophisticated system with enhanced operational management capabilities added to the existing facilities is necessary at this point. As traffic patterns of the urban traffic flow is time-specific due to the different vehicle populations throughout the time of the day, a local network-wide signal operation plan that can manage such situation-specific traffic patterns is deemed to be necessary. Therefore, this study is conducted for the purpose of establishment of a plan for contextual signal control management through signal optimization at the network level after setting the Frame Signal in accordance to the traffic patterns gathered from the short-term traffic forecast data as a means to mitigate the problems with existing standardized signal operations.

Heavy Metal Concentrations in the Mollusc Gastropod, Cipangopaludina chinensis malleata from Upo Wetland Reflect the Level of Heavy Metals in the Sediments

  • Kim, Heung-Tae;Kim, Jae-Geun
    • Journal of Ecology and Environment
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    • v.29 no.5
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    • pp.453-460
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    • 2006
  • Upo wetland is the largest inland wetland in Korea as Ramsar Convention Area. The purposes of the study were to investigate the levels of heavy metals (Cd, Cr, Cu, Ni, Pb and Zn) in the sediment and Cipangopaludina chinensis malleata from three sites of the wetland and to assess the potential of the gastropod as a bioindicator for heavy metal levels. The gastropods were dissected into shell and soft tissue without the digestive and excretive organs. The levels of Cd, Cu and Pb were below the guideline of Soil Environment Conservation Act and the heavy metals except Cr were slightly different among the sites. Cd was higher in Upo site ($0.32{\mu}g/g$) than Sajipo site ($0.28{\mu}g/g$). Cu and Zn showed the highest value in Sajipo as $43.5{\mu}g/g\;and\;39.8{\mu}g/g$, respectively while the concentrations of Pb and Zn were the highest in Upstream as $58.8{\mu}g/g\;and\;138{\mu}g/g$, respectively. In the soft tissues and shells of the gastropod, the overall common trend in the concentrations of the heavy metals was revealed with the following order: Zn > Cu > Cr > Ni > Pb > Cd and Ni > Zn > Cr > Cu > Pb > Cd, respectively. Although the soft tissues exhibited higher concentrations of the heavy metals except Ni than the shell in the gastropod, the levels of Cd and Pb in the gastropod were generally below the restrictive values set up by Korea Food & Drug Administration. From Duncan's Multiple Range Test (DMRT) results, the concentrations of Pb and Zn in the sediments among the sites were reflected on the soft tissue (Pb) and the shell (Pb and Zn) of the gastropod in the same order. The lower value of coefficient of variation (CV) in Pb concentration of the shell than in that of the soft tissue supports the usefulness of the shell as a bioindicator for Pb pollution. Although the CV value in the shell was a little higher than in the soft tissue, DMRT results and the stability of incorporated Zn into the shell support the use of the shell of the gastropod as a potential bioindicator for long-term contamination of Zn.

Survey on the Water Quality of Keum River (금강수질(錦江水質)에 관(關)한 조사연구(調査硏究))

  • Park, Jong-Seong;Oh, Man Jin
    • Korean Journal of Agricultural Science
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    • v.6 no.1
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    • pp.65-68
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    • 1979
  • Water of river gets great concern about its quality, which might be polluted with pollutant from various industrial plants booming along the river sides in recent years. As a first step to prevent any applciable damage due to water pollution, survey on the water quality of Keum river at Sintanjin, Maepo, Taepyongri, Kongju, Puyeo and Kanggeng, six regions was conducted during september, 1977 through august, 1978 and the results were summarized as follow: 1. There were no significant regional and monthly difference in pH, $NO_2-N$, and $NO_3-N$ of water. 2. The BOD at Puyeo, Kanggeng was 3.9 to 5.6, 5.6 to 6.0 ppm, respectively, and those values reached the limiting level for tap water sources. 3. The BOD at Maepo, where Daejeon streams meet, was found 1.9, 3.0, and 2.1 times higher than those at Sintanjin region, during september, october and november, respectvely. 4. Content of DO was $7.6{\pm}3.8ppm$ in all surveyed regions and varied with water temperature and regional difference. 5. There were found regional difference and monthly difference in water hardness, suspended solid and $NH_3-N$.

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Policy on the Development of the Oyster Industry (굴 산업 발전을 위한 정책 우선순위 결정)

  • Yu, Myung-gun;Mun, Tae-Hyoung
    • Management & Information Systems Review
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    • v.39 no.3
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    • pp.99-125
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    • 2020
  • This study analyzes the priority according to the importance of the government's oyster industry support policy using AHP (analytic hierarchy process), and it compares and confirms the satisfaction level of direct and indirect workers using this policy in contribution to the development of the oyster industry. The results of the importance analysis by AHP analysis are as follows: As a result of the evaluation of the importance of the entire sample, it is found that the most important factor is the production facilities of the production supply of the competitiveness enhancement, the purchase of raw materials of the production supply of the competitiveness enhancement, and the aging of the structural risks of risk reduction. Also, significant differences among the workers in the ranking of importance are identified. According to the comprehensive evaluation results of indirect workers, which consist of public officials, the National Federation of Fisheries Cooperatives, and related professors, raw materials, production facilities, and high-quality products are produced in order to increase competitiveness. There are differences among workers in order of marine pollution of environmental risks, structural fish population reduction, and structural aging of risk factors.

Study of Pro-environmental Development for Golf Course in Korea (한국 골프장의 친환경적 개발에 관한 연구)

  • 김광두
    • Asian Journal of Turfgrass Science
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    • v.12 no.1
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    • pp.49-78
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    • 1998
  • Nowadays, there are increasing demands of golf courses and it is necessary to make more golf courses than the present. To do this, we need to improve the environmental problems with the regional inhabitants, and it is said that the first thing to be considered in developing any golf course in Korea is to preserve the environment. In this context, the purpose of this study is to set forth several design factors to lessen the negative impacts which are accompanied with the development of golf courses. 1. The present conditions of golf courses in Korea Many new golf courses have come into being, particularly since the late 1980s, and now, in the year of 1997, over one hundred of golf courses are doing their business, yet the number of golf course is still less than required. So far, over a half of them have been made in the vicinity of Seoul on account of various reasons, and this has adversely affected on our natural environment. This unreasonable development of golf courses has caused serious water pollution, landslides and the other problems. Also, the topography of Korea is not good for golf courses. Although the demands of golf courses are increasing, the suitable sites for them are very limited, and therefore it is sometimes unavoidable to make golf courses on steep hills. Consequently, in designing golf courses in Korea, the most important thing is the balance between natural environment and artificial environment. 2.Eco-friendly golf course design factors 1) The concept of eco-friendly golf courses Ecologically sustainable and sound golf courses which are made by eco-friendly approaches 2)Basic conditions of eco-friendly golf courses (1)The most suitable sites (2) Conservation of existing ground as much as possible (3)Proper use of agricultural chemicals which have great impacts on the environment (4) Reasonable use of fertilizers (5) Developing a specialized fertilizer only for grass (6) Adaptation of organic agriculture (7) Improvement of grass sorts (8) Establishing reservoirs for purifying the water from golf courses 3) Eco-friendly golf courses (1) Location-Enough area /Gentle slope/Winding ground/Including lakes or streams /Not crossing wind's main direction Facing south or southeast /Suitable soIl for grass /Good drainage /Low level of underground water (2)Course layout and design -Consideration about existing contours as much as possible -Adaptation of Scotish design trend -Various holes' configuration -Consideration toward surrounding landscapes -Reducing grass areas -Giving buffer zones -Adapting computer methods in the process of site analysis and design (3) Eco-friendly considerations in constructing and managing golf courses -Protection of wildlife -Reuse of existing forests and preservation of topsoil -Renovation of old-fashioned courses -Reducing grass areas -Purification of water -Standization of management -Strict regulations against chemicals -Recycling organic materials -Through separation of the water inside golf courses and out of bounds -Getting proper construction works done in a due time 4.Eco-friendly considerations from a viewpoint of cultural environment 1) Well-matched landscape design and events planning 2) Implement of identifications and awarding systerns 3)Acknowledgement of superintendents' qualitications in the maintenance of golf courses 4)Increasing public golf courses and keeping good relationships with the neighbors near golf courses Key words: Pro-environmental development, Golf course.

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Stability analysis of an existing tunnel due to the excavation of a divergence tunnel emerging from double-deck tunnel (복층터널의 분기터널 굴착에 따른 기존터널의 안정성 분석)

  • Kim, Han-eol;Kim, Jung-Joo;Lee, Jae-Kook;Yoo, Han-Kyu
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.19 no.5
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    • pp.779-797
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    • 2017
  • Recently, underground road construction is attracting attention because the ground transportation facilities in the urban area have reached the saturation level and traffic volume has increased and the air pollution has risen. Construction of underground roads is not only reduce trafficjam in downtown but also design the city eco-friendly, so existing roads as well as new roads go underground. It is essential to construct divergence tunnels that serve as IC (interchage) and JC (Junction) when constructing underpasses. Therefore, the analysis of the effect of the existing tunnel by the divergence tunnel should be considered. In this study, numerical analysis is performed to analyze the effect of existing tunnel on the excavation of the divergence tunnel. The divergence tunnels were set in 5 cases at $45^{\circ}$ intervals in the clockwise direction starting from the lower part of the existing tunnel. In each case, numerical analyses were carried out by using the DCM (Displacement Controlled Model) for applying the volume loss of 0.5%, 1.0% and 1.5%. As a result, when the volume loss increased, the effect on displacement, fracture range, and effect on stability increased as well. In addition, it was confirmed that the divergence tunnel located directly underneath is the weakest for the stability, and the case where the divergence tunnel is located diagonally rather than the vertical and horizontal direction is found to be vulnerable to displacement and lining destruction.

A Study of Potential Buyers' Consciousness of Single-Family Housing in Ulsan (단독주택에 대한 울산시 거주자의 주의식 연구)

  • Kim, Ji-Suk;Yang, Se-Hwa
    • Journal of Families and Better Life
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    • v.28 no.6
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    • pp.35-46
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    • 2010
  • The purpose of the study was to identify the potential buyers' consciousness of single-family housing to provide useful data to help future single-family housing supplies in Ulsan. The study selected residents in Ulsan, who were over twenty and had an interest in living in a single-family housing. A survey was conducted from September 11, 2008 to September 25, 2008. The sample consisted of 364 persons who are currently live in Ulsan metropolitan area. The results are as following. About two thirds of the sample had the desire to live in a single-family housing. Moving into a single-family housing had financial preparation as the greatest issue. When moving into a single-family housing, the convenience of the residential district was the greatest consideration, whether or not it is a green environment, pollution level, etc. The potential buyers valued environment-friendly features and also had a very strong desire to own their own house. Many of them wanted to design and build their own single-family housing within a budget of 100-200 million KRW. In terms of the location, there was a higher preference for the riverside or lakeside rural areas outside the city. In terms of size, the preference was less than $330m^2$, which includes $99-132m^2$ for residential. When considering a single-family housing the direction was the most important feature, along with eco-friendly and safer materials and equipments. When building the single-family housing the potential buyers considered the community spaces first with a preference for having three bedrooms and two bathrooms. For the exterior, they wanted a unique shape of roof and there were high preferences for brown and beige colors. In terms of housing complexes, the potential buyers preferred individual unit types over complexes. If they preferred housing complexes, they wanted the cluster form complex with about 10-30 units. The complex also required a park-like setting with a guard system, which shows that convenience and safety were the most important features. In terms of complex management, they considered environmental management as the most important feature. The potential buyers were willing to pay belw 200,000 KRW, which showed their desire to minimize financial burdens.

Absorption of Copper(Cu) by Vegetation on Reservoir Sediment Exposed after Drawdown (저수위시 노출된 저수지 저니 상의 식생과 구리(Cu)의 흡수)

  • 이충우;차영일
    • Journal of Environmental Science International
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    • v.2 no.2
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    • pp.123-133
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    • 1993
  • Shingal reservoir is a relatively small (211ha) and shallow impoundment, and approximately 25 ha of its sediment is exposed after spring drawdown. At least 14 vascular p13n1 species germinate on the exposed sediment, but Persimria vulgaris Webb et Moq. quickly dominates the vegetation. In order to estimate the role of the vegetation in the dynamics of heavy metal pollutants in the reservoir, Cu concentration of water, fallout particles, exposed sediment, and tissues of p. vulgaris, Ivas analyzed. Cu content in reservoir water decreased from $13.10mg/m^2$ on May 15 (before dralvdown) to $3.08mg/m^2$ in June 1 (after drawdown), mainly due to the loiwering of water level. Average atmospheric deposition of Cu by fallout particles was $10.84 {\mu}g/m^2/day$. Cu content in the surface 15cm of exposed sediment decreased from $5.094g1m^2$ right after drawdown, to $0.530g/m^2$ in 41 days, which is a 89.6% decrease. Therefore up to 99.7% of Cu in the reservoir appears to exist in the sediment. only 0.3% in water If the rate of atmospheric Input by fallout particles is assumed to have been the same since 1958, when the reservoir was completed, cumulative input of Cu during the 38 years would have been $150.35mg/m^2$, which is only 3.0% of Cu content in sediment right after drawdown. Therefore, most of Cu in the Shingal reservoir must have been transported by the Shingal-chun flowing into the reservoir, Standing crop of vegetation on the exposed sediment 41 days after drawdown was $730.67g/m^2$, of which 630.91g/m2 was p. vulgaris alone, and Cu content in P vulgaris at this time was $6.612mg/m^2$. This was only 0.13% of Cu in the exposed sediment, but was 50.5% of Cu in water before drawdown, or 167% of the average annual input of Cu by atmospheric deposition. If other plants were assumed to absorb Cu to the same concentration as p. vulgaris, total amount of Cu absorbed in 41 days by vegetation on the exposed sediment is estimated to be 1913.3 g, which is a considerable contribution to the purification of the reservoir water.

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A Pilot Study on Emission Analysis of Air Pollutants Produced from Portable Recycling of Asphalt Concrete (간이이동법에 의한 폐아스콘 재생시 대기오염물의 배출분석에 대한 실험적 연구)

  • Lee, Byeong-Kyu;Kim, Haeng-Ah;Jeong, Ui-Ryang;Duong, Trang;Chae, Po-Gi;Park, Kyung-Won
    • Journal of Environmental Science International
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    • v.16 no.3
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    • pp.385-392
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    • 2007
  • Currently, portable equipment for recycling of waste asphalt concrete (ASCON) has been used. However, any air pollution control devices are not attached in the simple portable one. Thus, a lot of air pollutants have been produced from recycling processes of waste ASCON which resulted from aging of paved roads or repavement of roads. This study deals with a preliminary result of concentration analysis of air pollutants obtained from a pilot and a real recycling processes of waste ASCON using simple portable recycling equipment. Air pollutants were taken from 4 steps of the pilot recycling process including an initial heating by liquid petroleum gas (LPG), intermediate heating and melting (H&M) process, final H&M process, and pavement processes using recycled ASCON at the recycling site. Also, air pollutants were taken front 4 steps of the real recycling processes including an initial H&M, final H&M and mixing, loading of recycled ASCON to dump trucks, and at the recycling site after leaving the loaded dump trucks for real pavement sites. The air pollutants measured in this study include volatile organic compounds (VOCs), aldehydes, particulate matter (PM: PM1, PM2.5, PM7, PM10, TSP (total suspended particulate)). The identified concentrations of VOCs increased with increasing time or degree for H&M of waste ASCON. In particular, very high concentrations of the VOCs at the status of complete melting, which is exposed to the air, of the waste ASCON just before paving tv the recycled ASCON at the recycling site. Also, considerable amount of VOCs were identified from the recycling equipment after the dump trucks leaded by recycled ASCON leaved the recycling site for the pavement sites. The relative level of formaldehyde exceeded 80% of the aldehydes Identified in the recycling processes. This is because the waste ASCON is exposed to direct flame of LPG during H&M processes. The PM concentrations measured in the winter recycling processes, such as the loading and rotation processes of waste ASCON into/in the recycling equipment for H&M, were much higher than those in the summer ones. In particular, the concentrations of coarse particles such as PM7 and PM10 during the winter recycling were very high as compared those during the summer one.

Meteorological Characteristics of High-Ozone Episode Days in Daegu, Korea (대구시의 고농도 오존 발생 일에 나타나는 기상학적 특성)

  • Son, Im-Young;Kim, Hee-Jong;Yoon, Ill-Hee
    • Journal of the Korean earth science society
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    • v.23 no.5
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    • pp.424-435
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    • 2002
  • This study analyzes the surface ozone and meteorological data in Daegu for a period from 1997 to 1999. It also investigates the meteorological characteristics of high ozone episodes. For this study the high ozone episode has been defined as a daily maximum ozone concentration higher than 100ppb in at least one station among six air quality monitoring stations in Daegu, Korea. The frequency of episodes is 13 days. The frequency is the highest in May and September. The average value of daily maximum ozone concentration is 81.6ppb, and 8-hour average ozone concentration is 58.6ppb for the high episodes. This shows that ozone pollution is continuous and wide-ranging in Daegu. The daily maximum ozone concentration is positively correlated to solar radiation and daily maximum temperature, but negatively correlated to relative humidity, wind speed and cloud amount. The maximal correlation coefficient to solar radiation is 0.45. The differences between high ozone episode day's daily mean meteorological value and monthly mean value are +1.58hPa for sea level pressure, +3.45${\circ}$C for maximum temperature, -5.69% for relative humidity, -0.46ms$^{-1}$ for wind speed, -1.79 for cloud amount, and +3.97MJm$^{-2}$ for solar radiation, respectively. This shows that strong solar radiation, low wind speed and no precipitation between 0700${\sim}$1100LST are favorite conditions for high ozone episodes. It is related to the morning stagnant condition.