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Retrieval of Sulfur Dioxide Column Density from TROPOMI Using the Principle Component Analysis Method (주성분분석방법을 이용한 TROPOMI로부터 이산화황 칼럼농도 산출 연구)

  • Yang, Jiwon;Choi, Wonei;Park, Junsung;Kim, Daewon;Kang, Hyeongwoo;Lee, Hanlim
    • Korean Journal of Remote Sensing
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    • v.35 no.6_3
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    • pp.1173-1185
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    • 2019
  • We, for the first time, retrieved sulfur dioxide (SO2) vertical column density (VCD) in industrial and volcanic areas from TROPOspheric Monitoring Instrument (TROPOMI) using the Principle component analysis(PCA) algorithm. Furthermore, SO2 VCDs retrieved by the PCA algorithm from TROPOMI raw data were compared with those retrieved by the Differential Optical Absorption Spectroscopy (DOAS) algorithm (TROPOMI Level 2 SO2 product). In East Asia, where large amounts of SO2 are released to the surface due to anthropogenic source such as fossil fuels, the mean value of SO2 VCD retrieved by the PCA (DOAS) algorithm was shown to be 0.05 DU (-0.02 DU). The correlation between SO2 VCD retrieved by the PCA algorithm and those retrieved by the DOAS algorithm were shown to be low (slope = 0.64; correlation coefficient (R) = 0.51) for cloudy condition. However, with cloud fraction of less than 0.5, the slope and correlation coefficient between the two outputs were increased to 0.68 and 0.61, respectively. It means that the SO2 retrieval sensitivity to surface is reduced when the cloud fraction is high in both algorithms. Furthermore, the correlation between volcanic SO2 VCD retrieved by the PCA algorithm and those retrieved by the DOAS algorithm is shown to be high (R = 0.90) for cloudy condition. This good agreement between both data sets for volcanic SO2 is thought to be due to the higher accuracy of the satellite-based SO2 VCD retrieval for SO2 which is mainly distributed in the upper troposphere or lower stratosphere in volcanic region.

Optimization of fractionation efficiency (FE) and throughput (TP) in a large scale splitter less full-feed depletion SPLITT fractionation (Large scale FFD-SF) (대용량 splitter less full-feed depletion SPLITT 분획법 (Large scale FFD-SF)에서의 분획효율(FE)및 시료처리량(TP)의 최적화)

  • Eum, Chul Hun;Noh, Ahrahm;Choi, Jaeyeong;Yoo, Yeongsuk;Kim, Woon Jung;Lee, Seungho
    • Analytical Science and Technology
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    • v.28 no.6
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    • pp.453-459
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    • 2015
  • Split-flow thin cell fractionation (SPLITT fractionation, SF) is a particle separation technique that allows continuous (and thus a preparative scale) separation into two subpopulations based on the particle size or the density. In SF, there are two basic performance parameters. One is the throughput (TP), which was defined as the amount of sample that can be processed in a unit time period. Another is the fractionation efficiency (FE), which was defined as the number % of particles that have the size predicted by theory. Full-feed depletion mode (FFD-SF) have only one inlet for the sample feed, and the channel is equipped with a flow stream splitter only at the outlet in SF mode. In conventional FFD-mode, it was difficult to extend channel due to splitter in channel. So, we use large scale splitter-less FFD-SF to increase TP from increase channel scale. In this study, a FFD-SF channel was developed for a large-scale fractionation, which has no flow stream splitters (‘splitter less’), and then was tested for optimum TP and FE by varying the sample concentration and the flow rates at the inlet and outlet of the channel. Polyurethane (PU) latex beads having two different size distribution (about 3~7 µm, and about 2~30 µm) were used for the test. The sample concentration was varied from 0.2 to 0.8% (wt/vol). The channel flow rate was varied from 70, 100, 120 and 160 mL/min. The fractionated particles were monitored by optical microscopy (OM). The sample recovery was determined by collecting the particles on a 0.1 µm membrane filter. Accumulation of relatively large micron sized particles in channel could be prevented by feeding carrier liquid. It was found that, in order to achieve effective TP, the concentration of sample should be at higher than 0.4%.

A Study on Oil Price Risk Affecting the Korean Stock Market (한국주식시장에 파급되는 국제유가의 위험에 관한 연구)

  • Seo, Ji-Yong
    • The Korean Journal of Financial Management
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    • v.24 no.4
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    • pp.75-106
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    • 2007
  • In this study, it is analyzed whether oil price plays a major role in the pricing return on Koran stock market and examined why the covariance risk between oil and return on stock is different in each industry. Firstly, this study explores whether the expected rate of return on stock is pricing due to global oil price factors as a function of risk premium by using a two-factor APT. Also, it is examined whether spill-over effects of oil price volatility affect the beta risk to oil price. Considering the asymmetry of oil price volatility, we use the GJR model. As a result, it shows that oil price is an independent pricing factor and oil price volatility transmits to stock return in only electricity and electrical equipment. Secondly, the two step-analyzing process is introduced to find why the covariance between oil price factor and stock return is different in each industry. The first step is to study whether beta risk exists in each industry by using two proxy variables like size and liquidity as control variables. The second step is to grasp the systematic relationship between the difference of liquidity and size and beta to oil price factor by using the panel-data model which can be analyzed efficiently using the cross-sectional data formed with time series. Through the analysis, we can argue that oil price factor is an independent pricing factor in only electricity and electrical equipment having the greatest market capitalization, and know that beta risk to oil price factor is a proxy of size in the other industries. According to the result of panel-data model, it is argued that the beta to oil price factor augments when market capitalization increases and this fact supports the first assertion. In conclusion, the expected rate of return of electricity and electrical equipment works as a function of risk premium to market portfolio and oil price, and the reason to make beta risk power differentiated in each industry attributes to the size.

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The Predcitors of the Development of Acute Respiratory Distress Syndrome in the Patients with Acute Pancreatitis (급성 췌장염으로 내과계 중환자실에 입원한 환자들의 급성호흡곤란 증후군 발생에 연관된 인자에 관한 연구)

  • Yoo, Mi-Ran;Koh, Youn-Suck;Lim, Chae-Man;Lee, Moon-Gyu;Lee, Hong-Jae;Lee, Moo-Song;An, Jong-Jun;Lee, Sung-Koo;Kim, Myung-Hwan;Lee, Sang-Do;Kim, Woo-Sung;Kim, Dong-Soon;Kim, Won-Dong
    • Tuberculosis and Respiratory Diseases
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    • v.44 no.4
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    • pp.861-870
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    • 1997
  • Background : Though acute respiratory distress(ARDS) often occurs in the early stage of severe acute pancreatitis and significantly contributed to the mortality of the condition, the characteristics of the group who develops ARDS in the patients with acute pancreatitis have not been fully found. The objective of this investigation was to identify predictable factors which distinguish a group who would develop ARDS in the patients with acute pancreatitis. Method : A retrospective analysis of 94 cases in 86 patients who were admitted the Medical Intensive Care Unit with acute pancreatitis was done. ARDS were developed in 13 cases among them (13.8%). The possible clinical factors related to the development were analyzed using univariate analysis and $x^2$-test. Results : The risk of ARDS development was increased in the patients with abonormal findings of chest X-ray at admission compared to the patients with normal chest X-ray (p<0.05). The risk was also increased according to the sevecrity index score in abdominal computed tomography at the time of admission (p<0.05). The higher APACHE III score of the first day of admission, the more risk increment of ARDS development was observed (p<0.01). Patients with more than one points of Murray's lung injury score showed higher risk of ARDS compared to the patients with 0 points of that. The patients with sepsis and the patients with more than three organ dysfunction at admission had 3.5 times and 23.3 times higher risk of the development of ARDS compared to the patients without sepsis and without organ failure in each (p<0.05, p<0.01). Conclusion : The risk of ARDS development would be higher in the acute pancreatitis patients with abnormal chest X-ray, higher CT severity index, higher APACHE III or Murray's lung injury score, accompanying sepsis, and more than three organ failure at admission.

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The effect of using portfolio-based lessons on the development of self-identity of female middle school students and its two-year follow up - Focusing on the 'Understanding Adolescents' unit in middle school technology and home economics - (자아정체감 발달 수업에서의 포트폴리오 수업방법의 효과와 학년별 추이 - 기술.가정 교과의 청소년의 이해 단원을 중심으로 -)

  • Lee, Hyun-Jung;Cho, Byung-Eun
    • Journal of Korean Home Economics Education Association
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    • v.26 no.1
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    • pp.119-134
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    • 2014
  • This research looks at the effects of portfolio-based lessons to help female middle school students understand and develop their self identity, and to examine the influence of various factors within the school and home environment. The participants were 256 female middle school students in Gangneung-si, Gangwon-do and the analysis was done using the SPSS/WIN 12.0 program. The 6 portfolio-based teaching lessons were made with the aim of developing each subordinate scope in every module for development of self-receptiveness, uniqueness, closeness, tendency of planning the future, and independence. Results of the pre and post-test revealed that scores of self-receptiveness and uniqueness increased. Content analysis revealed that the students pursued their talents and interests through the portfolio activities, and made specific plans for their future careers. In sum, the results demonstrate that the students became specifically and systematically concerned about their future career. The results of hierarchical regression showed that self-receptiveness developed when their parents' attitudes were not rejecting and their peer relationships were positive. Uniqueness was shown to develop as the fostering attitudes of parents were receptive. Closeness developed as fostering attitudes of parents were receptive and as their relationships with peers were positive. The students' tendency to plan the future developed as fostering attitudes of parents were receptive and as their relationships with teachers were good, and independence was shown to develop as the fostering attitudes of parents were not rejecting. Results of a two-year follow-up study appeared that self-receptiveness scores decreased as time passed, so students had highest scores in their first year and lowest scores in their third year. Scores of uniqueness, tendency of planning the future, and identity increased in the students' second year and then remained steadily afterward.

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Effect of Fertilizer and Organic Matter Level on Marketable Tuber Production in Chinese Yam (Dioscorea opposita) (마(산약) 생산을 위한 시비법 개선연구)

  • Shin, Jong-Hee;Kim, Sang-Kuk;Kang, Dong-Kyoon;Park, Sang-Zo
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.59 no.2
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    • pp.144-150
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    • 2014
  • Yams (Dioscorea spp), which are edible or medicinal tuber crops, are a important crop in South Korea. Yams require a high level of soil fertility. The various cultural practices such as fertilizing and plowing were tested for marketable tuber production in Chinese yam (Dioscorea opposita). Tuber yield was also affected by organic matters in soil. Application higher level of organic matters result in increased each tuber weight and tuber yield per unit area. The nutrient absorption quantity of the plant such as nitrogen, phosphoric acid, calcium and potassium was increased from 100~120 days after planting, which time to begin tuber enlargement. The tuber yield was increased when the fertilization increased in quantity. Total yield and marketable ratio were the highest in 31~32 kg/10a of nitrogen fertilizer. From above result, income become larger with increase of marketable yield and quality improvement at 63% (27 kg/10a) level of conventional N fertilization (43 kg/10a). The tuber yield was not significantly different between with in various application level of potash fertilizer. Tuber size and weight decreased accordingly to decreased fertilizing level, so the rates of small tubers increased greatly at cultivation without chemical fertilizer. In considering the accumulation rates of allantoin in Chinese yam tubers, the apt harvest season was after October. The allantoin quantity of it was not influenced with nitrogen fertilizing. Moreover it was advantageous with decrease of chemical fertilizer and appropriate fertilizing in soil environment protection. Commercial tuber's number and yield were increased in trenching before planting with trencher compared with rotavating with tractor.

Studies on the Improvement of Mountainous Pasture III. Effect of seed coating on oversown pasture (산지초지 개량에 관한 연구 III. 종자 Coating에 의한 겉뿌림 초지육성)

  • 이인덕
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.4 no.3
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    • pp.194-200
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    • 1984
  • Effects of seed coating on establishment, early growth and herbage production were investigated in Pot, Soil box and Field experiments. Seed was coated with 60% Lime, 20% Phosphate and 20% Peatmoss(W/W), also finely sprayed 13% Arabic gum and 2% Methyl cellulose(W/V). Coating were generally 1:20, seed: coat(W/W). 1. In the general growth of the growing stages and different oversown species at 80 days, seed coated was promoted than none in early growth. (Table 2 and 3) 2. Stand counts at 60 days after oversown, seed coated was higher 15% than none, especially, there was advantage due to coating on the medium and large size seeds such as Orchardgrass, Perennial ryegrass and Kentucky bluegrass, but did not assist establishment of the large (Tall fescue) and small (Ladino clover) size seed. 3. Variation of sward composition was not quite different between two treatments, but seed coated was slightly increased the Percentage of sown grasses with advance of cutting time. 4. Total dry metter yield per unit area with seed coated was higher 17% than none in establishment year. 5. Variations in the chemical composition of the herbage and soil were influenced by coating materials in the coating regime (Table 8). 6. From these facts, seed coated also appeared that adequate seedling stands, early growth and herbage production could be obtained with higher than conventional overseeding method under a poor conditions.

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The Method of Participatory Government to Introduce the System of Autonomous Police (참여정부의 자치경찰제 도입방안)

  • Jung, Jin-Hwan
    • Korean Security Journal
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    • no.10
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    • pp.355-385
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    • 2005
  • As the system of autonomous police that has been debated for long time is fixed to be introduced by the program of participatory government, this treatise intends to analyze main contents and review controversial items in order to present supplementary measures. The program of participatory government to introduce autonomous police in Korea focuses on converting the autonomous police of Korea from centralized police administration in order to provide 'customized security service' that is appropriate to the regional environment. Thus, if relevant city, county or district considers that it is required to introduce the system autonomous police, the assembly may enforce the decision by enacting ordinance. For enforcement, organization in the unit of section will be established in the line of mayor, county headman and district office. The main role will be security service that is closely related to the life of inhabitants such as crime prevention, patrol, traffic crackdown, etc. as well as public health, sanitation and environmental control which are being performed by autonomous organization at present. However some expected controversial items may be summarized in the following 3 points on the premise of accepting the program of government. First, the point at issue related to the basic function of police. The basic function of police is generally understood as order keeping function such as anterior and preventive job and law enforcing function such as posterior and suppressing job. By the way, the program of government does not endow the autonomous police with investigation right for general crime, thereby raising the controversy that our autonomous police is nothing but the assistant of police. Furthermore, the present national police also expresses its dissatisfaction to the transfer of authority. Second, the issue of balance of security service between self-governing bodies may be raised. The security environment is different between self-governing bodies and thus demand of security is different. Therefore, the security service of autonomous police will reveal difference in qualitative aspect for each self-governing body. Moreover, it can be easily anticipated that the quality of security service may be different as per the financial independence degree. Third, the point at issue anticipated with the operation funded by the budget of self-governing body. As autonomous police is operated by the budget of self-governing body, the following problems may be raised; (1) since police administration is subordinated to general administration, the concentration may be weakened (2) the cooperation between policy agencies may be impeded (3) owing to the difficult in possessing spare police, the mobility of police may be somewhat reduced.

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The Effects of $\alpha$ -Adrenergic Drugs on the Myocardial Preconditioning in Rats. (교감신경계 약물의 허혈-재관류 후 심기능 회복에 미치는 영향)

  • 장원채;송상윤;오상기;안병희;김상형
    • Journal of Chest Surgery
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    • v.34 no.11
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    • pp.809-822
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    • 2001
  • Background: Ischemic preconditioning(IP) is known to be effective in the protection of myocardial necrosis, arrhythmia, and the restoration of the myocardial function in the ischemia-reperfusion state of the heart. However the exact mechanism is not clearly understood. The purpose of this study was to elucidate the trigger mechanism 7f IP on the restoration of the myocardial function after ischemia-reperfusion. Material and Method: By connecting a Langendorff perfusion apparatus with an isolated heart of a rat, the normal temperature of the heart was maintained. The experiment was conducted in seven groups, which were divided according to the preconditioning stimuli and blockage methods Group I(n=10) was a group without IP, Group II(n=10) a group of three-minute IP, Group III(n=10) a group of PEIP, Group IV(n=10) a group of clonidine IP, Group V(n=10) a group of If after reserpine, Group Vl(n=10) a group of PE & prazosin IP, and Group Vll(n=10) a group of clonidine & yohimbine IP. Hemodynamic parameters of DP, LVEDP, $\pm$dP/dT and the changes of perfusion in the coronary artery were evaluated. Result: Developed pressure and +dP/dT changed per unit time. After 20 minutes of reperfusion, those of Group II and III were 63.1$\pm$3.7%, 64.8$\pm$4.6% and 64.5$\pm$4.6%, 63.8$\pm$4.4%, which improved more significantly than those of Group I(P<0.05), However, there were no significant differences between the Groups V and Vl, and Group I. Conclusion: The Brief ischemic preconditioning and pharmacological preconditioning using $\alpha$-receptor sympatho-mimetics have protecting effects on the restoration of myocardial function after reperfusion. And the protecting effect of preconditioning seems to be related to sympathetic neurotransmitters and to the selective action of the $\alpha$$_1$-adrenergic receptor.

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Environmental Impact Assessment of Rapeseed Cultivation by Life Cycle Assessment (전과정평가를 이용한 유채재배의 환경영향 평가)

  • Hong, Seung-Gil;Nam, Jae-Jak;Shin, Joung-Du;Ok, Yong-Sik;Choi, Bong-Su;Yang, Jae-E.;Kim, Jeong-Gyu;Lee, Sung-Eun
    • Korean Journal of Environmental Agriculture
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    • v.30 no.1
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    • pp.24-30
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    • 2011
  • BACKGROUND: High input to the arable land is contributed to increasing productivity with causing the global environmental problems at the same time. Rapeseed cultivation has been forced to reassess its positive point for utilization of winter fallow field. The Objective of this study was performed to assess the environmental impact of rapeseed cultivation with double-cropping system in paddy rice on Yeonggwang district using life cycle assessment technique. METHODS AND RESULTS: For assessing each stage of rapeseed cultivation, it was collected raw data for input materials as fertilizer and pesticide and energy consumption rate by analyzing the type of agricultural machinery and working hours by 1 ton rapeseed as functional unit. Environmental impacts were evaluated by using Eco-indicator 95 method for 8 impact categories. It was estimated that 216 kg $CO_2$-eq. for greenhouse gas, 3.98E-05 kg CFC-11-eq. for ozone lazer depletion, 1.78 kg SO2-eq. for acidification, 0.28 kg $PO_4$-eq. for eutrophication, 5.23E-03 kg Pb-eq. for heavy metals, 2.51E-05 kg B(a)p-eq. for carcinogens, 1.24 kg SPM-eq. for smog and 6,460 MJ LHV for energy resource are potentially emitted to produce 1 ton rapeseed during its whole cultivation period, respectively. It was considered that 90% of these potential came from chemical fertilizer. For the sensitivity analysis, by increasing the productivity of rapeseed by 1 ton per ha, potential environmental loading was reduced at 22%. CONCLUSION(s): Fertilization affected most dominantly to the environmental burden, originated from the preuse stage, i.e. fertilizer manufacturing and transporting. It should be included and assessed an indirect emission, which is not directly emitted from agricultural activities. Recycling resource in agriculture with reducing chemical fertilizer and breeding the high productive variety might be contribute to reduce the environmental loading for the rapeseed cultivation.