• Title/Summary/Keyword: Yi Yi

Search Result 15,095, Processing Time 0.062 seconds

The PRISM-based Rainfall Mapping at an Enhanced Grid Cell Resolution in Complex Terrain (복잡지형 고해상도 격자망에서의 PRISM 기반 강수추정법)

  • Chung, U-Ran;Yun, Kyung-Dahm;Cho, Kyung-Sook;Yi, Jae-Hyun;Yun, Jin-I.
    • Korean Journal of Agricultural and Forest Meteorology
    • /
    • v.11 no.2
    • /
    • pp.72-78
    • /
    • 2009
  • The demand for rainfall data in gridded digital formats has increased in recent years due to the close linkage between hydrological models and decision support systems using the geographic information system. One of the most widely used tools for digital rainfall mapping is the PRISM (parameter-elevation regressions on independent slopes model) which uses point data (rain gauge stations), a digital elevation model (DEM), and other spatial datasets to generate repeatable estimates of monthly and annual precipitation. In the PRISM, rain gauge stations are assigned with weights that account for other climatically important factors besides elevation, and aspects and the topographic exposure are simulated by dividing the terrain into topographic facets. The size of facet or grid cell resolution is determined by the density of rain gauge stations and a $5{\times}5km$ grid cell is considered as the lowest limit under the situation in Korea. The PRISM algorithms using a 270m DEM for South Korea were implemented in a script language environment (Python) and relevant weights for each 270m grid cell were derived from the monthly data from 432 official rain gauge stations. Weighted monthly precipitation data from at least 5 nearby stations for each grid cell were regressed to the elevation and the selected linear regression equations with the 270m DEM were used to generate a digital precipitation map of South Korea at 270m resolution. Among 1.25 million grid cells, precipitation estimates at 166 cells, where the measurements were made by the Korea Water Corporation rain gauge network, were extracted and the monthly estimation errors were evaluated. An average of 10% reduction in the root mean square error (RMSE) was found for any months with more than 100mm monthly precipitation compared to the RMSE associated with the original 5km PRISM estimates. This modified PRISM may be used for rainfall mapping in rainy season (May to September) at much higher spatial resolution than the original PRISM without losing the data accuracy.

Suggestion for Technology Development and Commercialization Strategy of CO2 Capture and Storage in Korea (한국 이산화탄소 포집 및 저장 기술개발 및 상용화 추진 전략 제안)

  • Kwon, Yi Kyun;Shinn, Young Jae
    • Economic and Environmental Geology
    • /
    • v.51 no.4
    • /
    • pp.381-392
    • /
    • 2018
  • This study examines strategies and implementation plans for commercializing $CO_2$ capture and storage, which is an effective method to achieve the national goal of reducing greenhouse gas. In order to secure cost-efficient business model of $CO_2$ capture and storage, we propose four key strategies, including 1) urgent need to select a large-scale storage site and to estimate realistic storage capacity, 2) minimization of source-to-sink distance, 3) cost-effectiveness through technology innovation, and 4) policy implementation to secure public interest and to encourage private sector participation. Based on these strategies, the implementation plans must be designed for enabling $CO_2$ capture and storage to be commercialized until 2030. It is desirable to make those plans in which large-scale demonstration and subsequent commercial projects share a single storage site. In addition, the plans must be able to deliver step-wised targets and assessment processes to decide if the project will move to the next stage or not. The main target of stage 1 (2019 ~ 2021) is that the large-scale storage site will be selected and post-combustion capture technology will be upgraded and commercialized. The site selection, which is prerequisite to forward to the next stage, will be made through exploratory drilling and investigation for candidate sites. The commercial-scale applicability of the capture technology must be ensured at this stage. Stage 2 (2022 ~ 2025) aims design and construction of facility and infrastructure for successful large-scale demonstration (million tons of $CO_2$ per year), i.e., large-scale $CO_2$ capture, transportation, and storage. Based on the achievement of the demonstration project and the maturity of carbon market at the end of stage 2, it is necessary to decide whether to enter commercialization of $CO_2$ capture and storage. If the commercialization project is decided, it will be possible to capture and storage 4 million tons of $CO_2$ per year by the private sector in stage 3 (2026 ~ 2030). The existing facility, infrastructure, and capture plant will be upgraded and supplemented, which allows the commercialization project to be cost-effective.

Distribution and Stratigraphical Significance of the Haengmae Formation in Pyeongchang and Jeongseon areas, South Korea (평창-정선 일대 "행매층"의 분포와 층서적 의의)

  • Kim, Namsoo;Choi, Sung-Ja;Song, Yungoo;Park, Chaewon;Chwae, Ueechan;Yi, Keewook
    • Economic and Environmental Geology
    • /
    • v.53 no.4
    • /
    • pp.383-395
    • /
    • 2020
  • The stratigraphical position of the Haengmae Formation can provide clues towards solving the hot issue on the Silurian formation, also known as Hoedongri Formation. Since the 2010s, there have been several reports denying the Haengmae Formation as a lithostratigraphic unit. This study aimed to clarify the lithostratigraphic and chronostratigraphic significance of the Haengmae Formation. The distribution and structural geometry of the Haengmae Formation were studied through geologic mapping, and the correlation of relative geologic age and the absolute age was performed through conodont biostratigraphy and zircon U-Pb dating respectively. The representative rock of the Haengmae Formation is massive and yellow-yellowish brown pebble-bearing carbonate rocks with a granular texture similar to sandstone. Its surface is rough with a considerable amount of pores. By studying the mineral composition, contents, and microstructure of the rocks, they have been classified as pebble-bearing clastic rocks composed of dolomite pebbles and matrix. They chiefly comprise of euhedral or subhedral dolomite, and rounded, well-sorted fine-grained quartz, which are continuously distributed in the study area from Biryong-dong to Pyeongan-ri. Bedding attitude and the thickness of the Haengmae Formation are similar to that of the Hoedongri Formation in the north-eastern area (Biryong-dong to Haengmae-dong). The dip-direction attitudes were maintained 340°/15° from Biryong-dong to Haengmae-dong with a thickness of ca. 200 m. However, around the southwest of the studied area, the attitude is suddenly changed and the stratigraphic sequence is in disorder because of fold and thrust. Consequently, the formation is exposed to a wide low-relief area of 1.5 km × 2.5 km. Zircon U-Pb age dating results ranged from 470 to 449 Ma, which indicates that the Haengmae Formation formed during the Upper Ordovician or later. The pebble-bearing carbonate rock consisted of clastic sediments, suggesting that the Middle Ordovician conodonts from the Haengmae Formation must be reworked. Therefore, the above-stated evidence supports that the geologic age of the Haengmae Formation should be Upper Ordovician or later. This study revealed that the Haengmae Formation is neither shear zone, nor an upper part of the Jeongseon Limestone, and is also not the same age as the Jeongseon Limestone. Furthermore, it was confirmed that the Haengmae Formation should be considered a unit of lithostratigraphy in accordance with the stratigraphic guide of the International Commission on Stratigraphy (ICS).

Studies on Ichthyophthirius multifiliis Fouquet, 1876 in Freshwater Fishes II. Experimental Infection and Development of I. multifiliis (담수산 백점충(Ichthyophthirius multifiliis)에 관한 연구 II. 백점충의 인위 감염 및 어체내 충체 발달상)

  • Ji, Bo-Young;Kim, Ki-Hong;Park, Soo-Il;Kim, Yi-Cheong
    • Journal of fish pathology
    • /
    • v.11 no.1
    • /
    • pp.51-60
    • /
    • 1998
  • Concerned to the lyfe cycle of Ichthyophthirius multifiliis, the experimental infection and development of the parasites were studied in the several freshwater cultured fishes. Opitimum conditions for the propagation of the parasite by serial passage with the rainbow trout fry was observed. Visiable white spots were examined in the body surface, fins and gills of the healthy fries, and a stable infection has been maintained for 2 months in the experimental system (Temperature: $18{\pm}1^{\circ}C$ DO: 7-7.5 ppm; pH: $7{\pm}0.2$). Induction conditions for artificial infection of the parasite by interms of the host fishes, stages of the parasites, and rearing temperature regimes was investigated. Rainbow trout fries showed a positive infection which was resulted from exposure of theront at $18^{\circ}C$. The rainbow trout fries induced white spots on the body surface at 3-7 days exposure to the theronts at $18^{\circ}C$. It was found that exposure of the rainbow trout fries exposed to 1,000 theronts per fish (10 theront/ml) for 45-60 minutes at $18^{\circ}C$ would consistently produce infection. Perfect infection (100%) was induced when the fries were exposed to 1,500 theront per fish (15 theront/ml) under laboratory condition. Development of I. multifiliis in the rainbow trout was observed for 7 days postexposure (PE). The parasite increased in average diameter from $54{\mu}m$ on the 1st day PE to $426{\mu}m$ on the 7th day PE. In the initial infestation period, the parasites were found on the gill epithelium, and on the 3rd day PE they invaded into the basal part of the gill filament adjacent to the major blood vessels, particularly the afferent vessels. Morphological change of buccal apparatus were observed on the 2nd day PE. Contractile vacuoles were more prominent on the 4th day PE, and they had notable changes on the 7th day PE.

  • PDF

Evaluation of Residual Pesticides in Commercial Agricultural Products Using LC-MS/MS in Korea (LC-MS/MS를 이용한 한국에서 유통되는 농산물의 잔류 농약 평가)

  • Lee, Hwa-Mi;Hu, Soo Jung;Lee, Hyun-Sook;Park, Seung Young;Kim, Nam-Sun;Shin, Yong Woo;Choi, Keun Hwa;Kim, Sung Il;Nam, Seul Yi;Cho, Dae Hyun
    • Korean Journal of Food Science and Technology
    • /
    • v.45 no.4
    • /
    • pp.391-402
    • /
    • 2013
  • Pesticide residues in agricultural products in Korea were evaluated to create a data base to inform food policy. Pesticide residues were investigated in 17 commodities collected from 9 provinces in 2012. Our analytical method of multiresidue analysis, involved the analysis of individual recovery, linearity, limit of detection, and limit of quantitation of 60 pesticides in six matrices. The pesticides, including acetamiprid and forchlorofenuron, were evaluated in 358 agricultural samples by liquid chromatography/tandem mass spectrometry. Twenty three pesticides were detected from 67 samples. The results showed that the ratio of estimated daily intake to acceptable daily intake was 0.00009-0.0861% by the intake assessment, which means that residual pesticides in agricultural products in Korea are properly controlled.

Effect of Octreotide on Patients with Malignant Bowel Obstruction (악성장폐색 환자에서 Octreotide의 치료 효과)

  • Park, Ji-Chan;Jang, Yi-Sun;Jeon, Eun-Kyoung;Kim, Dong-Kyu;Lee, Wook-Hyun;Lee, Guk-Jin;You, Si-Young;Choi, Hyun-Ho;Park, Suk-Young
    • Journal of Hospice and Palliative Care
    • /
    • v.12 no.4
    • /
    • pp.194-198
    • /
    • 2009
  • Department of Internal Medicine, The Catholic University of Korea College of Medicine, Seoul, Korea Purpose: Malignant bowel obstruction causes gastrointestinal symptoms and leads to diminished quality of life in patients with advanced cancer. Several studies have shown the efficacy of octreotide for the relief of malignant bowel obstruction-related symptoms. The aim of this study is to assess the efficacy and safety of octreotide in patients with malignant bowel obstruction. Methods: We retrospectively reviewed medical records of twenty nine patients who had suffered from malignant bowel obstruction without clinical improvement of conservative care and subsequently, received octreotide treatment. Initial dosage of octreotide was 0.1 mg/day, and dose was escalated depending on the clinical effect. For each patient, we assessed visual analogue scale (VAS) of pain, number of vomiting episode, and amount of nasogastric tube drainage. Results: Median dosage of octreotide was 0.2 mg/day (range 0.1~0.6), and median duration from initial medication to death was 20 days (range 2~103). VAS before and after octreotide treatment were 5.6$\pm$1.24, and 2.7$\pm$0.96, respectively. The numbers of vomiting episode before and after octreotide treatment were 3.6/day$\pm$2.5, and 0.4/day$\pm$0.8, respectively. The mean amounts of nasogastric tube drainage before and after octreotide treatment were 975$\pm$1,083 cc/day and 115$\pm$196 cc/day, respectively. Statistically significant reduction in VAS, the number of vomiting episode and the amount of nasogastric tube drainage were observed after octreotide treatment (P<0.05). Conclusion: Administration of octreotide in patients with malignant bowel obstruction, which is uncontrolled by other medication, was effective and safe. In such clinical situations, physicians should consider to add of octreotide for symptomatic control.

  • PDF

QUANTITATIVE COMPARISON OF PERMEABILITY IN THE ADHESIVE INTERFACE OF FOUR ADHESIVE SYSTEMS (열순환 후 상아질 접착 계면의 수분 투과성 변화에 대한 정량적 분석)

  • Chang, Ju-Hea;Yi, Kee-Wook;Kim, Hae-Young;Lee, In-Bog;Cho, Byeong-Hoon;Son, Ho-Hyun
    • Restorative Dentistry and Endodontics
    • /
    • v.34 no.1
    • /
    • pp.51-60
    • /
    • 2009
  • The purpose of this study was to perform quantitative comparisons of water permeable zones in both the adhesive and the hybrid layer before and after thermo cycling in order to assess the integrity of the bonding interface. Twenty eight flat dentin surfaces were bonded with a light-cured composite resin using one of four commercial adhesives [OptiBond FL (OP), AdheSE (AD), Clearfil SE Bond (CL). and Xeno III (XE)]. These were sectioned into halves and subsequently cut to yield 2-mm thick specimens; one specimen for control and the other subjected to thermocycling for 10,000 cycles. After specimens were immersed in ammoniacal silver nitrate for 24 h and exposed to a photo developing solution for 8 h, the bonded interface was analyzed by scanning electron microscopy (SEM) and wavelength dispersive spectrometry (WDS) at five locations per specimen. Immediately after bonding. the adhesive layer of OP showed the lowest silver uptake, followed by CL, AD. and XE in ascending order (p < 0.0001); the hybrid layer of CL had the lowest silver content among the groups (p = 0.0039). After thermocycling, none of the adhesives manifested a significant increase of silver in either the adhesive or the hybrid layer. SEM demonstrated the characteristic silver penetrated patterns within the interface. It was observed that integrity of bonding was well maintained in OP and CL throughout the thermocycling process. Adhesive-tooth interfaces are vulnerable to hydrolytic degradation and its permeability varies in different adhesive systems, which may be clinically related to the restoration longevity.

The Relation of Maternal Stress with Nutrients Intake and Pregnancy Outcome in Pregnant Women (임신부의 스트레스와 영양상태 및 임신결과와의 관련성)

  • Kim, Yi-Jung;Lee, Sang-Sun
    • Journal of Nutrition and Health
    • /
    • v.41 no.8
    • /
    • pp.776-785
    • /
    • 2008
  • Maternal stress was one of the common symptoms that pregnant women could have experienced during pregnant period. The purpose of this study was to investigate the relation of maternal stress with maternal nutrients intake and pregnancy outcome. Subjects were 248 pregnant women and were recruited at two hospitals in Seoul area. Individual stress levels were divided by the stress scores (total 41 scores), as low stressed group (< 12) and high stressed group (${\geqq}12$). The social characteristics, nutrient intake, anthropometric measurements and pregnancy outcome were compared between low stressed group (LSG) and high stressed group (HSG) to recognize risk factor of maternal stress. We found that subjects experience stress by various factors which were concern about newborn (40.4%), concern about health (28.8%), economic difficulties (13.2%), depress (10.1%), family relationship (2.9%), concern of house work (2.5%), human relationship (2%). In HSG, unemployed rate (p < 0.05) and pre-pregnancy BMI (p < 0.05) were higher than in LSG. Family size in HSG was larger than that in LSG (p < 0.01). Doing regular exercise with the light activity level was significantly higher in LSG (p < 0.05). The nutrient intake in LSG was slightly higher than that in HSG, but not statistically significant. Pregnancy outcome was not significantly affected by the maternal stress. In conclusion, the risk of maternal stress may be related with a life style during pregnancy. Therefore, life style for maternal stress control, such as weight control and regular exercise is recommended to prevent maternal stress.

The Making of Speaking Subject in Early Korean Protestantism: Focused on the Educational Spaces for Women (초기 한국 기독교의 교육공간과 말하는 주체의 탄생)

  • Lee, Sookjin
    • Journal of Christian Education in Korea
    • /
    • v.62
    • /
    • pp.227-255
    • /
    • 2020
  • This paper aims to explore the nature of the making of speaking subject in early Korean Protestantism, focusing on the educational spaces for women. Traditional women could become a speaking subject through various educational programs provided by Protestantism in modern Korea. Especially three kinds of educational space played the crucial role of making women a speaking subject. The first was Bible class established for women in rural areas. Since most Korean women were unable to read and write, Protestant churches taught them Hangul[Korean alphabet] before teaching the Bible. Korean women studied the Bible in Bible class, Women's Bible School, and Women's High Bible School. Through this education, traditional women were liberated from the world of ignorance and obedience, and then become a speaking subject. The second was speeches and discussions that have emerged in institutional spaces such as mission schools for girls and women's organizations. Students at mission school were able to learn how to express their opinions by way of public speaking and discussion classes. Women were able to become speaking subjects in the process of learning such techniques of modern language. At that time, representative discussion spaces were Lee Mun-hoe, Joyce Chapter, and YWCA. The third was testimony and dialect. Unlike sermons and public prayers, which were only allowed to male elites, testimony and dialectics are a form of speech that transcends gender or status constraints. Especially in the space of the revival movement, women confirmed their dignity through active testimony, and their religious identity was strengthened in the process. Dialect also served as the language of liberation for women suffered and alienated from male-dominant culture. Dialect is a device that exercises the right to speak against transcendental authority. Furthermore, in Protestantism of early modern Korea, the speaking subject's act of speech was elevated beyond personal matters to social issues, women's issues, and ethnic issues.

Urban Climate Impact Assessment Reflecting Urban Planning Scenarios - Connecting Green Network Across the North and South in Seoul - (서울 도시계획 정책을 적용한 기후영향평가 - 남북녹지축 조성사업을 대상으로 -)

  • Kwon, Hyuk-Gi;Yang, Ho-Jin;Yi, Chaeyeon;Kim, Yeon-Hee;Choi, Young-Jean
    • Journal of Environmental Impact Assessment
    • /
    • v.24 no.2
    • /
    • pp.134-153
    • /
    • 2015
  • When making urban planning, it is important to understand climate effect caused by urban structural changes. Seoul city applies UPIS(Urban Plan Information System) which provides information on urban planning scenario. Technology for analyzing climate effect resulted from urban planning needs to developed by linking urban planning scenario provided by UPIS and climate analysis model, CAS(Climate Analysis Seoul). CAS develops for analyzing urban climate conditions to provide realistic information considering local air temperature and wind flows. Quantitative analyses conducted by CAS for the production, transportation, and stagnation of cold air, wind flow and thermal conditions by incorporating GIS analysis on land cover and elevation and meteorological analysis from MetPhoMod(Meteorology and atmospheric Photochemistry Meso-scale model). In order to reflect land cover and elevation of the latest information, CAS used to highly accurate raster data (1m) sourced from LiDAR survey and KOMPSAT-2(KOrea Multi-Purpose SATellite) satellite image(4m). For more realistic representation of land surface characteristic, DSM(Digital Surface Model) and DTM(Digital Terrain Model) data used as an input data for CFD(Computational Fluid Dynamics) model. Eight inflow directions considered to investigate the change of flow pattern, wind speed according to reconstruction and change of thermal environment by connecting green area formation. Also, MetPhoMod in CAS data used to consider realistic weather condition. The result show that wind corridors change due to reconstruction. As a whole surface temperature around target area decreases due to connecting green area formation. CFD model coupled with CAS is possible to evaluate the wind corridor and heat environment before/after reconstruction and connecting green area formation. In This study, analysis of climate impact before and after created the green area, which is part of 'Connecting green network across the north and south in Seoul' plan, one of the '2020 Seoul master plan'.