• Title/Summary/Keyword: 농도차

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Issues and Tasks for Air Quality Management in the Greater Seoul Metropolitan Area (수도권 대기질 관리의 쟁점과 과제)

  • Ghim, Young-Sung
    • Journal of Environmental Policy
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    • v.4 no.1
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    • pp.1-19
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    • 2005
  • On January 1, 2005, the Special Act on Metropolitan Air Quality Improvement, known as the Blue Sky 21 Program, entered into force. This Special Act is aimed at reducing the annual average concentrations of $PM_{10}$ and $NO_2$ to $40{\mu}g/m^3$ and 22ppb, respectively, from their current levels of $76{\mu}g/m^3$ and 36ppb, within the next 10 years. While the main focus of the Act is to reduce $PM_{10}$ and $NO_2$ emissions, the government also anticipates that these reductions would lessen high ozone occurrences and improve visibility. However, reducing local PM emissions would not decrease $PM_{10}$ concentrations as much as expected since other significant sources, such as continental inflow and/or secondary formation from photochemical reactions, exist. This is corroborated by the fact that $PM_{10}$ in the greater Seoul Metropolitan area during the ozone season is mostly in the form of $PM_{2.5}$, which is secondarily formed on a regional scale. Furthermore, many modeling results indicate so-called '$NO_x$ disbenefits,' referring to the fostering of an increase in ozone concentrations from a decrease in $NO_x$ emissions, over an extensive area. In this paper, the current status of air quality in the Seoul Metropolitan area is reviewed, and several other issues, including the effect of long-range transport, photochemical characteristics, and tasks for successful implementation of the Special Act are discussed.

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Immunotoxicity Study of Separated Antigen from Helicobacter pylori. (Helicobacter pylori로부터 유래된 항원의 항원성에 관한 연구)

  • Park, Chang-Ho;Bae, Man-Jong
    • Journal of Life Science
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    • v.18 no.4
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    • pp.494-502
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    • 2008
  • The anaphylaxis shock reaction on the whole cells of H. pylori exhibited a symptom of slight illness for the first and second medication of causing antigen at an antigen concentration of WC (H) $60\;{\mu}g/100\;{\mu}l$ for WC (H) and no anaphylaxis shock symptom was observed at an antigen concentration of $20\;{\mu}g/100\;{\mu}l$ for WC (L). In the case of anaphylaxis shock reaction on the crude urease, no symptom was observed at an antigen concentration of $20\;{\mu}g/100\;{\mu}l$ for both urease (L) and urease (H). In the heterologous passive cutaneous anaphylaxis (PCA) test using a guinea pig-rat, no positive reaction was detected in all the medication groups of WC (H), WC (L), urease (H) and urease (L). In the skin sensitization test, it was observed that the best antigen concentration not causing skin disorder at each of $80\;{\mu}g/100\;{\mu}l$, $40\;{\mu}g/100\;{\mu}l$, $20\;{\mu}g/100\;{\mu}l$, and $20\;{\mu}g/100\;{\mu}l$ was $40\;{\mu}g/100\;{\mu}l$.

An Analysis of the Effects of Fine Dust Reduction Policies on PM10 Concentration and Health Using System Dynamics (시스템다이내믹스를 활용한 미세먼지 저감 정책이 미세먼지 농도와 건강에 미치는 영향 분석)

  • Seho Lee;Jung Eun Kang;Ji-Yoon Lee;Minyeong Park;Ji Yoon Choi
    • Journal of Environmental Impact Assessment
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    • v.32 no.5
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    • pp.318-337
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    • 2023
  • This study utilizes system dynamics to examine the effects of fine dust reduction policies on PM10 concentration and health. System dynamics has the advantage of modeling the dynamic and circular relationship between PM10 emission sources, reduction policies, PM10 concentration, and health effect. The study created policy scenarios for Korea's representative fine dust reduction policies - industrial PM10 emission control, diesel vehicle regulation, expansion of electric vehicles, and expansion of parks and green areas - and compared the results with the 2030 baseline if the current trend is maintained. The analysis showed that the policy of supporting electric vehicles reduced PM10 concentration by 0.21 ㎍/m3 and reduced the number of people with circulatory diseases by 494, and the effect was evenly distributed across the country. The industrial emissions regulation scenario resulted in the highest PM10 concentration reduction of 0.22 ㎍/m3, but had a lower reduction in the number of people affected (358) than the EV support strategy, which could be attributed to the fact that this policy had a particularly high PM10 reduction effect in industrial areas such as Danyang-gun, Chungcheongbuk-do, and Sahagu, Busan. As a policy implication, this study suggests that it is necessary to apply fine dust policies tailored to the characteristics of local emission sources.

Growth Characteristics according to GA3 Treatment of Angelica acutiloba (Siebold & Zucc.) Kitagawa (일당귀의 GA3 처리에 따른 생육특성)

  • Dae Hui Jeong;Yeong Bae Yun;Jeong Hoon Huh;Hong Woo Park
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2022.09a
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    • pp.46-46
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    • 2022
  • 본 연구의 목적은 약용과 식용으로서의 활용도가 높은 일당귀[Angelica acutiloba (Siebold & Zucc.) Kitagawa]의 GA3농도에 따른 생육특성을 확인하고, 최적의 재배기술 개발 및 지속가능한 안정적인 작물생산에 대한 기초자료의 제공에 있다. 연구재료는 강원도 태백시에 위치하는 일당귀 재배농가에서 2021년 10월에 채종한 종자를 구입하였고, 영주시 풍기읍에 위치한 연구온실에서 연구를 수행하였다. 일당귀의 종자를 증류수에 48시간 침지 후 GA3농도 4조건(50 ppm, 100 ppm, 500 ppm, 1,000 ppm)에 24시간 처리 후 72구 포트에 파종 후 출아율과 생육특성을 조사하였다. 연구결과 일당귀 종자는 16일이 경과한 시점부터 출아를 시작하였고, 500 ppm처리구에서 73.3%로 가장 높은 출아율을 나타냈다. 생육특성조사는 출아 후 40일(1차)과 80일(2차) 경과된 시점에서 총 2회를 수행하였는데 1차 생육조사에서는 주근길이와 직경을 제외한 모든 생육특성에서 처리구별 생육의 차이가 확인되지 않았으나 2차 생육조사에서는 지상부와 지하부의 모든 생육특성에서 처리구별 생육의 차이가 확인되었다. 잎수(6.3개)와 주근길이(4.26 cm)는 500 ppm처리구에서 가장 높은 생육량을 나타냈고, 지상부 높이(21.81 cm), 잎길이(9.0 cm), 잎너비(10.77 cm), 주근직경(5.71 mm)은 1,000 ppm처리구에서 가장 높은 생육량을 나타냈다. 따라서 GA3 처리에 따른 일당귀의 생육특성은 생육초기보다 후기로 갈수록 발현량이 높게 나타나는 것으로 판단된다. 또한 저농도의 GA3처리보다 500-1,000 ppm 사이의 처리농도가 적합한 것으로 판단되며, 추후 일당귀의 유용성분 분석을 통한 이화학적 연구가 추가된다면 최적의 재배기술 확립을 통한 안정적인 작물 생산에 기여할 수 있을 것이라 사료된다.

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A Preliminary Study on Oral Molodor Measurement (구취측정에 관한 예비 연구)

  • 김영구
    • Journal of Oral Medicine and Pain
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    • v.22 no.2
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    • pp.233-239
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    • 1997
  • 현대사회에서 구취의 유무가 가정 및 사회생활을 유지하는데 중요한 문제로 대두됨에 따라 구취의 예방과 치료에 관심이 증대되고 있다. 많은 연구자들에 의해 구취에 관한 연구가 이루어지고 있으며, 특히 구취의 연구에서는 객관적이며 정확한 구취의 측정이 중요한 과제가 되고 있다. 이에 저자들은 건강한 구강조직을 가진 서울대학교 치과대학생 및 치과병원 종사자 21명을 대상으로 시각차에 대한 실험, 구강세정에 대한 실험, 구강내로 삽입되는 straw의 구강내 위치에 대한 실험, straw의 종류에 대한 실험 및 구강내 타액의 양에 대한 실험을 실시한 결과 아래와 같은 결론을 얻었다. 1. 휘발성 황화합물의 농도는 하루중 기상직후 식사나 잇솔질하기 전에서 가장 높았다. 2. 잇솔질과 zinc chloride 양치후 휘발성 황화합물 농도의 유의한 감소를 보였다(p<0.05). 3. 측정시 straw가 구강내로 들어가는 깊이가 줄어들수록 휘발성 황화합물의 농도가 유의하게 감소하였다. (p<0.05). 4. 측정에 사용된 straw의 종류는 휘발성 황화합물의 농도에 영향을 주지 않았다. 5. 구강내에 타액을 머금고 측정했을 매 휘발성 황화합물 농도의 유의한 감소가 관찰되었고(p<0.05), 숨을 쉬지않고 측정했을 때는 변화가 관찰되지 않았다 6. 구취 측정시 개구정도에 따른 측정값의 유의한 차이는 관찰되지 않았다.

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A meta analysis for anti-hyperlipidemia effect of soybeans (메타분석을 이용한 대두의 항-고지혈 효과)

  • Kim, Ji-Eun;Choi, Ki-Heon
    • Journal of the Korean Data and Information Science Society
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    • v.21 no.4
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    • pp.651-667
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    • 2010
  • In this paper, using a meta analysis of anti-hyperlipidemia effect of soybeans were studied. Studied the effects of soybeans using Hedges' standardized mean difference looked at the effect. Applying the fixed-effects model analysis of fecal cholesterol and total cholesterol and triglycerides showed a statistically significant reduction in HDL cholesterol increase was statistically significant at. In addition, the homogeneity of all variables by running the test did not meet the homogeneity of the kidney weight, between weight, HDL cholesterol, LDL cholesterol, total cholesterol, and triglycerides in the random effects model against the results of the analysis conducted by a statistically significant variable that did not.

Evaluation of Complex Odor and Odorous Compounds in a Pilot-Scale Ultra Thermophilic Aerobic Composting Process (초고온 호기성 퇴비화 공정의 복합 악취 및 악취 물질 평가)

  • Park, Seyong;Jung, Dai-Hyuck;Yoo, Eui-Sang;Kim, Moonil
    • Journal of the Korean GEO-environmental Society
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    • v.10 no.5
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    • pp.33-39
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    • 2009
  • This study was conducted to evaluate production of complex odor and 12 specific odorous compounds in a pilot-scale (capacity : $100m^3$) ultra thermophilic aerobic composting. There were three types input: municipal wasted sludge, livestock manure and slurry, and food waste produced in Jung-Eb city. Each raw material was mixed with seed material and operated for two periods (1st : 50 days, 2nd : 60days). During composting, the temperature hit $90{\sim}95^{\circ}C$ after every mixing in both periods. Therefore, it was concluded that increasing temperature also saves the time which required for composting and high reduction of organics and water contents. The primary odorous compounds were ammonia, methyl mercaltan, dimethyl disulfide and trimethylamine. The concentration of the primary compounds and complex odor during the operation were higher than those on final day and most compounds did not exceed the allowable exhaust standard for odor. Also, it was found that optimal mixing time and control of high temperature are the most important parameters for odor control in ultra thermophilic aerobic composting.

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Numerical Studies on the Effects of the Channel-Inlet-Pressure Difference in the Pressure-Retarded Osmosis (PRO) Power System (압력지연삼투(PRO) 발전 시스템에서 채널 입구 압력차의 영향에 대한 수치해석적 연구)

  • Hong, Sung Soo;Ryoo, Won;Chun, Myung-Suk;Chung, Gui Yung
    • Korean Chemical Engineering Research
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    • v.52 no.1
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    • pp.68-74
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    • 2014
  • In the spiral wound module of the pressure-retarded osmosis (PRO) system for the salinity gradient power generation, effects of the inlet pressure differences between feed-channel and draw-channel were studied. Fluxes of water and solute through membrane and power were estimated. The water flux through membrane decreased along the x-direction and increased along the y-direction with the increase of inlet pressure differences between two channels. On the other hand, the solute flux through membrane showed the opposite trend. The concentration of flow in the feed-channel increased a lot along the y-direction and that in the draw-channel decreased along the x-direction. In our system, for the inlet pressure differences of 1~11 atm, the flow rate in the feed-channel decreased about 8~13% and that in the draw-channel increased by the same amount. The power density increased and then decreased with the increasing inlet pressure difference.

The Effects of Training on Body Fat and Blood Lipid (운동효과가 체지방 및 혈중 지질에 미치는 영향)

  • 최현숙;안응남
    • Journal of Life Science
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    • v.8 no.5
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    • pp.563-570
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    • 1998
  • The seven (7) housewives were used as subjects at three times per weeks for twelve (12) weeks in order to find out the effects of aerobic exercise and weight training on body composition and blood lipid. Each subject's weight, lean body mass, percent body fat, BMI and blood lipid were measured immediately after the training and the results compared with the same prior to exercises were obtained as follows ; 1. The weight and percent body fat of the subjects were slightly but not significantly decreased, however the lean body mass following training was significantly increased with 1.3 %. BMI S RBW were also not significantly decreased. 2. Calory intake was 1929.9 cal before the training and 1896.0 cal after the training, which doesn't shows much difference. 3. The blood lipid such as TC and LDL-C were a little increased after the training, but HDL-C shows significant increase of 22.7 %, and HDL-C/TC was significantly increased with 13.2 % (p<.05 ) as well. However, TG shows significant decrease (p<.05 ).

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Anti-Oxidative and Anti-Inflammatory Effect of Water Extract from Perillae Semen in RBL-2H3 Cells (RBL-2H3 세포에서 차조기씨 물 추출물의 항산화 및 항염증 효과)

  • Kim, Jeong-Mi;Kim, Dae-Jung;Kim, Tae-Hyuk;Kim, Hyun-Sook;Choe, Myeon
    • Journal of Nutrition and Health
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    • v.43 no.4
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    • pp.367-373
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    • 2010
  • The present study was to investigate anti-oxidative and anti-inflammatory activity of Perillae semen in RBL-2H3 basophilic leukemia cells. Inhibitory effect of Perillae semen onto free radical generation was determined by measuring DPPH and hydroxyl radical scavenging activities in vitro. Anti-inflammatory actions of Perillae semen extracts (100, 250, $500\;{\mu}g/mL$) were assessed by testing their effects on the degranulation of mast cells. For this, $\beta$-hexosaminidase released from RBL-2H3 cells was used and proinflammatory cytokines were measured by an ELISA kit. Our results indicated that Perillae semen water extracts effectively inhibited free radical generation. At the concentration of $500\;{\mu}g/mL$ of water extract, the degranulation of RBL-2H3 cells were inhibited by 42.1%. The IgE-antigen complex increased the accumulation of IL-4 and TNF-$\alpha$ secretion in RBL-2H3 cells and treatments with 250 and $500\;{\mu}g/mL$ of Perillae semen extracts suppressed the IgE induced secretion of IL-4 and TNF-$\alpha$ protein by 20.5, 26.9% and 14.5, 16.5% respectively. We observed that Perillae semen water extract reduced $\beta$-hexosaminidase, IL-4, and TNF-$\alpha$ secretion in RBL-2H3 cells. These results provide that Perillae semen may be beneficial in the treatment of allergic inflammatory disease.