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PM10 Mass Concentration at Keumgangsan, North Korea - from September 2007 to May 2008 - (금강산(金剛山)에서 관측한 미세먼지 농도 - 2007년 9월부터 2008년 5월까지 -)

  • Kim, Jeong Eun;Shim, Wonbo;Lim, Jaechul;Chun, Youngsin
    • Atmosphere
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    • v.21 no.4
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    • pp.447-454
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    • 2011
  • As dust storms originated in Neimongu Plateau and Manchuria became more frequent in Korea, there was a growing need for Asian Dust (Hwangsa) monitoring stations in North Korea, which is a pathway of Asian Dust to South Korea. The South Korean and the North Korean Governments agreed to build the Automatic Weather System and the PM10 measurement instruments in the Gaeseong Industrial Zone and the Keumgangsan Tourist Region, North Korea in 2007. PM10 mass concentration data in the Keumgangsan Tourist Region could be collected only during the period from September 2007 to May 2008. In this study, daily, monthly and diurnal variations of PM10 mass concentration of the Keumgangsan are analyzed and compared with those of Sokcho and Gwangdeoksan. Three sites show similar variations in daily and monthly means. Correlation coefficients (r) between Sokcho and Keumgangsan, and between Gwangdeoksan and Keumgangsan are 0.89 and 0.67, respectively. But diurnal variation at Keumgangsan has a distinct feature compared to the other sites. Diurnal PM10 variation shows two peaks around 8 AM and 4-5 PM and very low at night. The difference between the daily maximum and minimum is 2060μgm3 during September to November 2007. Temperature, relative humidity and wind speed from the Keumgangsan AWS data were compared with those from the Changjon station, and showed good correlation each other except wind speed.

Simulation of Atmospheric Dispersion over the Yosu Area -I. Terrain Effects- (여수지역 대기확산의 수치 모사 -I. 지형의 영향-)

  • 김영성;오현선
    • Journal of Korean Society for Atmospheric Environment
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    • v.16 no.3
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    • pp.211-223
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    • 2000
  • The atmospheric dispersion of a pollutant emitted from a hypothetical source located in the middle of the Yochon Industrial Estate was simulated by using the Regional Atmospheric Modeling System (RAMS). Four horizontally nested grids were employed: the coarsest one covered the southern part of the Korean Peninsula including Mt. Chiri and the finest one covered the Yochon Industrial Estate and the surrounding area. Wind fields were initially assumed horizontally homogeneous with a wind speed of 4m/s, the average for the Yosu area, and were developed without both external forces and diurnal changes in order to investigate the terrain-induced phenomena. Wind directions that could emphasize the terrain effects on the pollutant transport and that could carry pollutants to a highly-popluated area were selected for the dispersion study. A pollutant was released for 24hours from a grid-base volume source after a 24-h blank run for developing the wind field. The dispersion study showed that the pollutant from the present source location did not directly affect the Yosu City, but showed high concentrations at locations behind the hills 5 to 6 km away from the source according to wind directions. When the wind speed was low, close to calm condition, the pollutant was detected at upstream locations 6 to 7 km from the source. In comparison with the results from the RAMS simulation, the Industrial Source Complex Short-Term Model(ISCST3) predicted a narrow dispersion that was sensitive to the wind direction. When the wind velocity was affected by the local environment, the ISCST3 calculation using that data also gave a lop-sided result, which was different from the distribution of the pollutant reproduced by RAMS.

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Landscape Information Visualization of Landscape Potential Index in Hilly Openspace Conservation of Urban Fringe Area (도시주변 녹지경관의 보전.관리에 있어 경관잠재력 지표의 경관정보화와 가시화 연구)

  • Cho, Tong-Buhm
    • Journal of Korean Society of Rural Planning
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    • v.7 no.1 s.13
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    • pp.37-48
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    • 2001
  • The purpose of this study is to suggest the landscape potential index for visualizing landscape information in the conservation of hilly landscape in urban fringe. For the visual and quantitative approach to topological landscape assessment, numerical entity data of DEM(digital elevation model) were processed with CAD-based utilities that we developed and were mainly focused on analysis of visibility and visual sensitivity. Some results, with reference in assessing greenbelt area of Eodeung Mt. in Gwangju, proved to be considerable in the landscape assessment of suburban hilly landscapes. 1) Since the viewpoints and viewpoint fields were critical to landscape structure, randomized 194 points(spatially 500m interval) were applied to assessing the generalized visual sensitivity, we called. Because there were similar patterns of distribution comparing to those by 56 points and 18 Points given appropriately, it could be more efficient by a few viewpoints which located widely. 2) Regressional function was derived to represent the relationships between probabilities of visibility frequency and the topological factors(topological dominance, landform complexity and relational aspect) of target field. 3) Visibility scores of each viewpoint were be calculated by summing the visual sensitivity indices within a scene. The scores to the upper part including ridge line have been more representative to overall distributions of visual sensitivities. Also, with sum of deviations of sensitivity indices from each single point's specific index to the weighting values of view points could be estimated rotationally. 4) The deviational distributions of visual sensitivity classes in the topological unit of target field were proved to represent the visual vulnerability of the landform. 5) Landscape potential indices combined with the visual sensitivity and the DGN(degree of green naturality) were proposed as visualized landscape information distributed by topological unit.

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Carbohydrate and Ginsenoside Changes in Ginseng Roots Grown in the Bay of Plenty, New Zealand

  • Follett John M.;Proctor John T.A.;Walton Eric F.;Boldingh Helen L.;McNamara Catherine;Douglas James A.
    • Journal of Ginseng Research
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    • v.28 no.4
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    • pp.165-172
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    • 2004
  • Ginseng is traditionally cultivated worldwide in cold continental climates. It is now also being cultivated in maritime environments such as New Zealandis. This paper reports a number of growth and quality parameters for plants grown under those conditions over two growing seasons and the intervening winter dormant period. While shoot biomass peaked mid-summer, in contrast, root biomass peaked late autumn/early winter. Starch, sucrose, fructose, glucose and inositol were detected in the roots. Starch concentrations were highest in early autumn (mean 470 mg g1 dry weight) and lowest in mid spring (218 mg g1 dry weight). Sucrose concentrations were low during early summer until late autumn but increased rapidly with the onset of winter and peaked during mid spring (168 mg g1 dry weight). Fructose and glucose concentrations were similar and peaked in late spring (5.3 and 6.2 mg g1 dry weight). Inositol concentrations peaked in mid summer (1.7 mg g1 dry weight). Starch/sugar ratios were high during summer and autumn and low during winter and spring. Ginsenoside concentrations and profiles showed that the six major ginsenosides, Rgl, Re, Rb1, Rc, Rb2 and Rd, were present, but Rf was absent. Concentrations did not vary with sampling date. The most abundant ginsenosides were Re (15.9 to 17.5 mg g1 dry weight) and Rb1 (10.7 to 18.1 mg g1 dry weight). Combined, they accounted for < 75% of total ginsenoside concentrations. Limited taste tests indicated that highest root quality occurred during late autumn, after the shoots had senesced. However, quality could not be related to plant chemistry.

Characteristics of Atmospheric Circulation in Sokcho Coast (속초연안에서 대기순환의 특성)

  • Choi Hyo
    • Journal of Environmental Science International
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    • v.14 no.1
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    • pp.41-51
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    • 2005
  • Using three-dimensional non-hydrostatical numerical model with one way double nesting technique, atmo­spheric circulation in the mountainous coastal region in summer was investigated from August 13 through 15, 1995. During the day, synoptic westerly wind blows over Mt. Mishrung in the west of a coastal city, Sokcho toward the East Sea, while simultaneously, easterly upslope wind combined with both valley wind from plain (coast) toward mountain and sea-breeze from sea toward inland coast blows toward the top of the mountain. Two different directional wind systems confront each other in the mid of eastern slope of the mountain and the upslope wind goes up to the height over 2 km, becoming an easterly return flow in the upper level over the sea and making sea-breeze front with two kinds of sea-breeze circulations of a small one in the coast and a large one in the open sea. Convective boundary layer is developed with a thickness of about 1km over the ground in the upwind side of the mountain in the west and a thickness of thermal internal boundary layer from the coast along the eastern slope of the mountain is only confined to less than 200 m. On the other hand, after sunset, no prohibition of upslope wind generated during the day and downward wind combined with mountain wind from mountain towardplain and land-breeze from land toward under nocturnal radiative cooling of the ground surfaces should intensify westerly downslope wind, resulting in the formation of wind storm. As the wind storm moving down along the eastern slop causes the development of internal gravity waves with hydraulic jump motion in the coast, bounding up toward the upper level of the coastal sea, atmospheric circulation with both onshore and offshore winds like sea-breeze circulation forms in the coastal sea within 70 km until midnight and after that, westerly wind prevails in the coast and open seas.

Re-establishment of Park Nature Conservation Area in Bukhansan (Mt.) National Park Using Marxan with Zones (Marxan with Zones 적용을 통한 북한산국립공원 공원자연보존지구 재설정 방안 연구)

  • Yeum, Jung-Hun;Han, Bong-Ho
    • Journal of Environmental Science International
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    • v.26 no.2
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    • pp.133-146
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    • 2017
  • This study aimed to develop strategies to re-establish the Park Nature Conservation Area in Bukhansan National Park, reflecting landscape ecological value by using the zonation program Marxan with Zones. Planning unit was set by watershed, and the basic data were mapped, considering topographical and ecological values. Mapped indicators were analyzed with the application framework of Marxan with Zones by indexing some indicators. The zones divided into Park Nature Conservation Area (Zone A), Park Nature Environment Area I(Zone B) which is reflected on the concept of Potential Park Nature Conservation Area and Park Nature Environment Area II(Zone C). The best solution for each of the scenarios was fixed through the sensitiveness analysis. From these, the final solution was selected considering five criteria including area ratio of conservation area and grouping. Lastly, the final solution was verified in the overlapped analysis with recent zonation. According to the results, the number of watersheds was 77, with an average area of 1,007,481m2. In terms of basic mapping and indexation, the slope index and number of landscape resources for topographical property were average 0.22 and 38 places, respectively. Biotope index was average 0.69 and legally protected species was 14 species, reflecting ecological values. As the social and economic indicators, trail index was average 0.04, and the number of tour and management facilities was 43 places. Through the framework of Marxan with Zones, the best solution for scenario 1 which was set by the highest conservation criteria was selected as the final solution, and the area ratio of Park Nature Conservation Area and grouping was excellent. As the result of overlapped analysis, suggested zonation of the Park Nature Conservation was better than the recent zonation in the area raito (28.3%), biotope grade I(15.4%) and the distribution points (10 places) of legally protected species with verification of proper distribution of conservation features according to the zone.

Studies on Pollution Characteristics and Sources of Precipitation in Jeiu Island

  • Kang, Chang-Hee;Kim, Won-Hyung
    • Journal of Korean Society for Atmospheric Environment
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    • v.18 no.E4
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    • pp.191-201
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    • 2002
  • The pH, electric conductivity. and the major ionic components were analyzed for the precipitation samples collected at 1100 Site of Mt. Halla and Jeju city. The quality of analytical data was verified by the comparison of ion balances, conductivities and acid fractions, all of which correlation coefficients were over 0.952. The ionic strengths lower than 104 M were found in 57 and 28% at 1100 Site and Jeju city respectively. The precipitation in Jeju city was influenced more by the oceanic effect than those in 1100 Site. The acidification of precipitation was caused mostly by S O42and N O3[10] in both areas, and the organic acids have contributed to the acidity with only 7~8%. The neutralization factors by N H3 were about 44 and 47% at the 1100 site and the Jeju city, respectively, whereas those by CaC O3were 21 and 24%, and the free acidity were about 38 and 28% at two sites. From the investigation of seawater and soil enrichment factors, the S O42, N O3[10] and N E4+ were immigrated by other sources rather than from the seawater or soil origins. but not in the case of Mg2+, C l[10] , N a+, and K+. Factor analysis has shown that the precipitation at the 1100 site had been influenced mostly by anthropogenic sources, followed by soil and sea-water sources. On the other hand, the precipitation at the Jeju city was mainly influenced by oceanic sources, followed by anthropogenic and soil sources.urces.

Multi-wavelength Study of Blazars Using Variability as a Tool

  • Baliyan, Kiran S.;Kaur, Navpreet;Chandra, Sunil;Sameer, Sameer;Ganesh, Shashikiran
    • Journal of Astronomy and Space Sciences
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    • v.33 no.3
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    • pp.177-183
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    • 2016
  • Active galactic nuclei (AGN) are too compact to be resolved by any existing optical telescope facility, making it difficult to understand their structure and the emission processes responsible for their huge energy output. However, variability, one of their characteristic properties, provides a tool to probe the inner regions of AGN. Blazars are the best candidates for such a study, and hence a considerable amount of effort is being made to investigate variability in these sources across the electromagnetic spectrum. Here, using the Mt. Abu infrared observatory (MIRO) blazar monitoring program, we present intra-night, inter-night, and long term aspects of the variability in S5 0716+71, 3C66A, and OJ 287. These stars show significant variability on short (a few tens of mins, to a few hours, to a few days) to long term (months to years) timescales. Based on the light travel time argument, the shortest variability timescales (micro-variability) provide upper limits to the size of the emission region. While S5 0716 shows a very high duty cycle of variability (> 80 %), 3C66A shows a much lower intra day variability (IDV) duty cycle (< 20 %). All three show rapid variations within 2.5 to 3.5 hr, which, perhaps, are generated near the vicinity of black holes. Assuming this, estimates of the masses of the black holes are made at ~109, 8×108, and 2.7×109 M for S5 0716+71, 3C66A, and OJ 287, respectively. Multi-wavelength light-curves for the blazar PKS 1510-089 are discussed to infer the emission processes responsible for the recent flaring episodes in this source.

In vitro Evaluation of Anti-Human Immunodeficiency Virus Activity of Nucleoside Derivatives and Studies on Their Mode of Action (핵산유도체들의 항 Human Immunodeficiency Virus in vitro 약효평가와 작용기전연구)

  • Lee, Chong-Kyo;Kim, Dong-Ki;Kim, Jee-Hyun;Kim, Hae-Soo;Pi, Mi-Kyoung;Park, Jong-Beak;Kim, Baek
    • The Journal of Korean Society of Virology
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    • v.27 no.1
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    • pp.69-75
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    • 1997
  • To evaluate in vitro anti-HIV efficacies of nucleoside derivatives, MT-4 cell line was infected with HIV-1 and HIV-2 respectively and treated with various compounds and the formerly approved drugs such as AZT, d4T, ddC and ddI. CPE method was used to evaluate their antiviral activity. Most dideoxynucleosides, AZT, d4T, ddC and ddI, showed anti-HIV activities against both viruses but no other compounds including anti-herpesvirus drugs did any. Further experiments were carried out to study their inhibitory mechanism of viral adsorption. The results showed no inhibition of syncytium formation due to an interaction between the gp120 expressed in HIV -infected cell surface and CD4 receptor on the uninfected cell surface in the presence of AZT. AZT showed no activity up to 100μg/ml. Inhibition of reverse transcriptase (RT) in the presence of AZT-triphosphate was tested by using RT expressed in E. coli and purified and its IC50 was 4.5 nM.

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Low-Level Wind Shear (LLWS) Forecasts at Jeju International Airport using the KMAPP (고해상도 KMAPP 자료를 활용한 제주국제공항에서 저층 윈드시어 예측)

  • Min, Byunghoon;Kim, Yeon-Hee;Choi, Hee-Wook;Jeong, Hyeong-Se;Kim, Kyu-Rang;Kim, Seungbum
    • Atmosphere
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    • v.30 no.3
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    • pp.277-291
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    • 2020
  • Low-level wind shear (LLWS) events on glide path at Jeju International Airport (CJU) are evaluated using the Aircraft Meteorological Data Relay (AMDAR) and Korea Meteorological Administration Post-Processing (KMAPP) with 100 m spatial resolution. LLWS that occurs in the complex terrains such as Mt. Halla on the Jeju Island affects directly aircraft approaching to and/or departing from the CJU. For this reason, accurate prediction of LLWS events is important in the CJU. Therefore, the use of high-resolution Numerical Weather Prediction (NWP)-based forecasts is necessary to cover and resolve these small-scale LLWS events. The LLWS forecasts based on the KMAPP along the glide paths heading to the CJU is developed and evaluated using the AMDAR observation data. The KMAPP-LLWS developed in this paper successfully detected the moderate-or-greater wind shear (strong than 5 knots per 100 feet) occurred on the glide paths at CJU. In particular, this wind shear prediction system showed better performance than conventional 1-D column-based wind shear forecast.