• Title/Summary/Keyword: Heo hun

Search Result 516, Processing Time 0.027 seconds

Ensemble Daily Streamflow Forecast Using Two-step Daily Precipitation Interpolation (일강우 내삽을 이용한 일유량 시뮬레이션 및 앙상블 유량 발생)

  • Hwang, Yeon-Sang;Heo, Jun-Haeng;Jung, Young-Hun
    • Journal of Korea Water Resources Association
    • /
    • v.44 no.3
    • /
    • pp.209-220
    • /
    • 2011
  • Input uncertainty is one of the major sources of uncertainty in hydrologic modeling. In this paper, first, three alternate rainfall inputs generated by different interpolation schemes were used to see the impact on a distributed watershed model. Later, the residuals of precipitation interpolations were tested as a source of ensemble streamflow generation in two river basins in the U.S. Using the Monte Carlo parameter search, the relationship between input and parameter uncertainty was also categorized to see sensitivity of the parameters to input differences. This analysis is useful not only to find the parameters that need more attention but also to transfer parameters calibrated for station measurement to the simulation using different inputs such as downscaled data from weather generator outputs. Input ensembles that preserves local statistical characteristics are used to generate streamflow ensembles hindcast, and showed that the ensemble sets are capturing the observed steamflow properly. This procedure is especially important to consider input uncertainties in the simulation of streamflow forecast.

Crystallographic analysis of dehydrated fully Tl+-exchanged zeolite Y

  • Lim, Woo Taik;Kwon, Ji Hye;Choi, Sik Young;Kim, Young Hun;Heo, Nam Ho
    • Analytical Science and Technology
    • /
    • v.18 no.4
    • /
    • pp.278-286
    • /
    • 2005
  • The crystal structure of ($Tl_{71}$-Y ($Tl_{71}Si_{121}Al_{71}O_{384}$), ${\alpha}=24.706(3){\AA}$, dehydrated at 653 K and $8{\times}10^{-6}$ torr, has been determined by single-crystal X-ray diffraction techniques in the cubic space group $Fd\bar{3}m$ at 294(1) K. The structure was refined using all intensities to the final error indices (using only the 302 reflection for which $F_{\circ}$ > $4{\sigma}(F_0)$) $R_1=0.0602$ (based on F) and $R_w=0.1744$ (based on $F_2$). The 71 $Tl^+$ ions per unit cell are found at four crystallographically distinct positions. Site I' position in the sodalite cavity opposite D6Rs are each occupied by eighteen $Tl^+$ ions per unit cell; these $Tl^+$ ions are recessed ca. $1.45{\AA}$ into the sodalite cavity from their O(3) plane (Tl-O=2.701(15), $3.163(16){\AA}$ and O-Tl-O=$92.1(4)^{\circ}$). The 23 $T1^+$ ions fill site II in the supercage; these $T1^+$ ions are recessed ca. $1.58{\AA}$ into the supercage from their O(2) plane (Tl-O = 2.850(16), $3.156(16){\AA}$ and O-T1-O = $85.1(5)^{\circ}$). The 19 $Tl^+$ ions lie at site III' in the supercage near a triple 4-ring (Tl-O = 3.10(7), $3.39(5){\AA}$ and O-Tl-O = 47.8(9), $95.3(18)^{\circ}$) and the remaining II ions occupy another site III' near a triple 4-ring in the supercage (Tl-O = 2.81(4), $2.71(4){\AA}$ and O-Tl-O = $57.3(8)^{\circ}$).

Simulation of Soil Erosion due to Snow Melt at Alpine Agricultural Lands (고령지 농경지에서 융설에 의한 토양유실량 모의)

  • Heo, Sung-Gu;Lim, Kyoung-Jae;Kim, Ki-Sung;Myung, SaGong;An, Jae-Hun
    • Proceedings of the Korean Society of Agricultural Engineers Conference
    • /
    • 2005.10a
    • /
    • pp.241-246
    • /
    • 2005
  • Doam watershed is located at alpine areas in the Kangwon province. The annual average precipitation, including snow accumulation during the winter, at the Doam watershed is significantly higher than other areas. Thus, pollutant laden runoff and sediment discharge from the alpine agricultural fields are causing water quality degradation at the Doam watershed. To estimate soil erosion from the agricultural fields, the Universal Soil Loss Equation (USLE) has been widely used because of its simplicity to use. The USLE rainfall erosivity (R) factor is responsible for impacts of rainfall on soil erosion. Thus, use of constant R factor for the Doam watershed cannot reflect variations in precipitation patterns, consequently soil erosion estimation. In the early spring at the Doam watershed, the stream flow increases because of snow melt, which results in erosion of loosened soil experiencing freezing and thaw during the winter. However, the USLE model cannot consider the impacts on soil erosion of freezing and thaw of the soil. Also, it cannot simulate temporal changes in USLE input parameters. Thus, the Soil and Water Assessment Tool (SWAT) model was investigated for its applicability to estimate soil erosion at the Doam watershed, instead of the widely used USLE model. The SWAT hydrology and erosion/sediment components were validated after calibration of the hydrologic component. The $R^2$ and Nash-Sutcliffe coefficient values are higher enough, thus it was found the SWAT model can be efficiently used to simulate hydrology and sediment yield at the Doam watershed. The effects of snow melt on SWAT estimated stream flow and sediment were investigated using long-term precipitation and temperature data at the Doam watershed. It was found significant amount of flow and sediment in the spring are contributed by melting snow accumulated during the winter. Thus, it is recommend that the SWAT model capable of simulating snow melt and long-term weather data needs to be used in estimating soil erosion at alpine agricultural land instead of the USLE model for successful soil erosion management at the Doam watershed.

  • PDF

Characterization of a bacterium isolated from diseased rock sea bream, Oplegnathus fasciatus, during low water temperature season in Jeju island (저수온기의 제주도 양식 돌돔, Oplegnathus fasciatus, 병어로부터 분리한 병원세균의 특성)

  • Go, Dae-Hui;Jin, Chang-Nam;Lee, Chang-Hun;Park, Geun-Tae;Heo, Mun-Su
    • Journal of fish pathology
    • /
    • v.17 no.2
    • /
    • pp.83-90
    • /
    • 2004
  • The outbreak of haemorrhagic specticemia and lesions in dermis, frequently associated with keratitis have occured on rock sea bream (Oplegnathus fasciatus) reared in Jeju island. A bacterium isolated from the diseased fish identified as Pseudomonas sp. by morphologic, cultural, and biochemical tests. The bacterium was identified Pseudomonas anguilliseptica according to 16S rDNA sequence analysis. The highest growth rate of this strain was obtained at 20 to $\25^circ{C}$ although the disease occurred mostly below $16^\circ{C}$. The challenge test by ip injection revealed that this bacterium was pathogenic to rock sea bream. All experimental fish in challenged by ip injection died within 21 days but there was no death in control group. The bacterium was sensitive to Doxycycline, Chloramphenicol, Ciprofloxacin, Erythromycin, Flumequine, Nalidixic acid, Norfloxacin, and Ofloxacin.

The Effect of Cancer Associated Fibroblasts(CAFs) and CD44 of CAFs on the Motility of Cancer Cells in Head and Neck Squamous Cell Carcinoma (두경부편평세포암에서 암-연관 섬유아세포가 암세포의 운동성에 미치는 영향과 암-연관 섬유아세포에서 과발현되는 CD44의 역할)

  • Shim, Seon-Hui;Hah, J. Hun;Cho, Soo Youn;Kim, Tae-Min;Koh, Young-Il;Kim, Dong-Wan;Lee, Choon-Taek;Heo, Dae Seog;Sung, Myung-Whun
    • Korean Journal of Head & Neck Oncology
    • /
    • v.30 no.2
    • /
    • pp.43-52
    • /
    • 2014
  • 배경 및 목적 암-연관 섬유아세포(Cancer-associated fibroblasts, CAF)는 종양미세환경의 가장 중요한 요소의 하나다. 그래서 두경부편평세포암에 대해 CAF가 암세포의 운동성에 미치는 영향을 평가하고, CAF에 과발현되는 CD44의 역할에 대해 평가하고자 하였다. 재료 및 방법 두경부암환자의 종양조직에서 CAF를 분리하고, 비종양성 조직으로부터 정상 섬유아세포(NHF)를 분리하였다. 창상치유분석과 상하 챔버를 이용한 3차원 세포 이동 분석을 이용하여, CAF가 암세포의 이동에 미치는 영향을 분석하고, CAF에서 과발현되는 CD44를 중화항체로 CAF를 차단했을 때 암세포 이동의 변화를 관찰하였다. 결과 NHF에 비해 CAF에서 CD44가 과발현되는 것을 관찰하였다. 창상치유분석에서 CAF와 같이 배양된 암세포는 NHF와 같이 배양된 암세포에 비해 더 빠른 이동을 보였다. CD44 중화 항체를 처리했을 때는 암세포의 이동성이 저해되었다. 결론 CAF는 종양미세환경에서 암세포의 운동성을 조절하는 중요한 인자의 하나일 것으로 사료된다. CD44는 CAF의 기능을 매개하는 중요한 표지자 중 하나로 생각된다.

Efficient Callus Induction and Plant Regeneration from Immature and Mature Embryo Culture of Korean Wheat Genotypes

  • Lee, Byung-Moo;Moon, Jung-Hun;Lee, Sang-Kyu;Kim, Kyung-Hee;Kang, Moon-Seok;Heo, Hwa-Young;Kwon, Young-Up;Nam, Jung-Hyun;Seo, Yong-Weon
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.48 no.1
    • /
    • pp.38-43
    • /
    • 2003
  • Immature and mature embryos of 18 Korean wheat genotypes were cultured in vitro to develop an efficient method of callus formation and plant regeneration, and to compare the responses of both embryo cultures. Immature and mature embryos were placed on a solid agar medium containing the MS salts and vitamins, 30g/l maltose, 2 mg/l 2,4-dichlorophenoxyacetic acid (2,4-D), and amino acids. The developed calli were maintained on regeneration medium containing MS salts and B5 vitamins, 20 g/l sucrose, and the combination of two plant growth regulators, 6-benzylaminopurine (BAP) and indole-3-acetic acid (IAA). Immature embryos in most genotypes showed high efficiency of callus induction except three genotypes; Eunpamil, Chunggemil, and Namhaemil, and significant differences among the genotypes. Plant regeneration of calli induced from immature embryos showed high efficiency in Geurumil (56.5%), Tapdongmil (50.5%), Gobunmil (45.5%), and Urimil(42.2%). The analysis of variance showed significant differences for regeneration frequency among the genotypes. Mature embryos showed low callus induction frequency compared with that in immature embryos, and significant differences among the genotypes. Plant regeneration of calli induced from mature embryos showed high efficiency in Keumkangmil (33.33%), Tapdongmil(28.13%), and Geurumil (27.78%). The analysis of variance showed significant differences for plant regeneration frequency among the genotypes.

THE CLINICAL STUDY ON PAROTID GLAND TUMOR (이하선 종양의 임상적 연구)

  • Shin, Sang-Hun;Heo, June;Kim, Ki-Hyen;Chung, In-Kyo
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
    • /
    • v.26 no.1
    • /
    • pp.80-84
    • /
    • 2000
  • Tumors of the parotid gland are the most frequently encountered salivary gland tumors. Knowledge of the histology and anatomy of the salivary gland is important when considering the histiogenesis of salivary gland tumors, requiring close cooperation between the pathologist and the surgeon. Most tumors are benign epithelial formations. Pleomorphic adenomas predominate. Superficial lobectomy is adequate treatment. When the tumor involves a deep lobe, total parotidectomy is indicated. Treatment of malignant tumors depends on the histology, its TNM stage and other factors. Total parotidectomy with lymph adectomy and radiotherapy are needed in case of high grade malignancy. In children, vascular neoplasias are the most frequent, followed by malignant tumors. Their histological features and treatment are the same as for adults. We reviewed 64 cases of the parotid tumors at Department of surgery, Dong-A University Hospital from July. 1990 to Jan. 1999 for the purpose of apprehension of parotid gland tumor by the clinical study and review. Over all sex ratio was 1:1.13(M:F), mean age was 38.9 years, mean size was 3.53cm. According to histologic findings of 64 cases, pleomorphic adenoma was 55(85.9%), Warthin's tumor was 3(4.7%), mucoepidermoid carcinoma was 3(4.7%), squamous cell carcinoma was 2(3.1%), acinic cell carcinoma was 1(1,6%). Post op. facial nerve palsy 16(25%), Frey's syndrome 11(17.2%) cases were happened. Hence, the clinical manifestation of pain, tenderness, facial N. palsy suggest malignant tumors.

  • PDF

Expression of Osteoprotegerin and Osteoclast Differentiation Factor in Human Periodontal Ligament Fibroblast Cells (치주인대 섬유아세포에서 Osteoprotegerin과 Osteoclast Differentiation Factor의 발현)

  • Rew, Seong-Hun;Heo, Soo-Rew;Kim, Hyung-Seop;O, Kwi-Ok
    • Journal of Periodontal and Implant Science
    • /
    • v.32 no.4
    • /
    • pp.721-731
    • /
    • 2002
  • Recently, soluble TNF receptor homolog osteoprotegerin(OPG) and its membrane-bound ligand osteoclast differentiation factor(ODF) were found to regulate osteoclast formation and function, and bone metabolism. It is now well established that ODF acts via RANK expressed on hematopoietic osteoclast precursor cells to facilitate their differentiation to osteoclasts, and OPG prevents the formation of osteoclasts by interfering the binding of ODF and RANK. Expression of OPG and ODF was believed to be closely related to the pathogenesis of bone resorption and destruction from osteoporosis, periodontal diseases, malignant bone tumor, and arthritis. The periodontal ligament fibroblasts (PDLF), located between the tooth and tooth socket, has been thought to play an important role in maintaining bone homeostasis of periodontal tissues. However, the exact mechanism by which bone formation and resorption are regulated by PDLF is not well understood. In this study we have prepared primary cultures of human PDLF from periodontium of malaligned tooth extracted due to orthodontic reason, and determined steady state or inflammatory signal-induced OPG and ODF expression using RT-PCR and western blot analysis. OPG and ODF mRNA and protein were expressed constitutively in the PDLF and these expression were slightly increased by osteotropic cytokine IL-1 ${\beta}$. Lipopolysaccharide-treated PDLF showed decrease in OPG mRNA and protein expression, and increase in ODF mRNA and protein expression. These results indicated that PDLF influence the osteoclastogenesis by OPG and ODF expression in the inflammatory situation as well as physiological condition, and thereby pathogenesis of periodontal alveolar bone destruction.

Effects of Gagambojungikgi-tang on the Immune Mediators Regulation and Wound Healing in the rSj26 or Chemical Antigen induced Atopic Dermatitis Model Mice (rSj26 또는 화학 항원 유도 아토피 피부염 마우스 모델에서 가감보중익기탕의 면역 매개물 조절 및 상처치료 효과)

  • Heo, Jung-Hun;Song, Han-Na;Jang, Seon-Il
    • The Korea Journal of Herbology
    • /
    • v.23 no.1
    • /
    • pp.53-61
    • /
    • 2008
  • Objectives : The aim of this study was to investigative the effects of Gagambojungikgi-tang (GBT), a Korean herbal medicine, on the immune mediators, T cell proliferation and wound healing in the recombinant Sj26 (rSj26) antigen induced atopic dermatitis(AD) model mice. Methods : GBT is the water extracts prepared from mixture of Ginseng Radix, Astragali Radix, Angelicae gigantis Radix, Atractylodes Rhizoma alba, Aurantii nobilis Pericarpium, Glycyrrhizae Radix, Artemisia iwayomogi Herba, Scutellaria Radix, Lonicera japonica Flos. This is a modified prescription of Bojungikgi-tang, which has been used for the treatment of indigestion, and immunological disease in east-asian countries. GBT was orally administered or externally applied at difference doses. The levels of immune mediators [(IgE, IgG1, prostaglandin E2 (PGE2), Th1/Th2 cytokines], T cell proliferation, and wound healing in the rSj26 or chemical antigen induced AD model BALB/c were investigated. Results : GBT dose-dependently suppressed the release of TNF-${\alpha}$, IL-$1{\beta}$ (Th1 cytokines), IL-4, IL-10 (Th2 cytokines), PGE2 (inflammatory mediators) and T cell proliferation. But GBT increased the production of IFN-${\gamma}$ (Th1 cytokine). Furthermore, A wound healing effect of GBT was similar to external application of dexamethasone. Conclusions : These results suggest that GBT suppresses the inflammatory mediators and regulates the Thl/Th2 cytokines, and promotes the wound healing. Therefore, these properties may contribute to the strong anti-AD effect of GBT.

  • PDF

The Role of Water Utility Industry to the National Economy (수도사업의 국민경제적 역할분석)

  • Kim, Tae-Yu;Yu, Seung-Hun;Heo, Eun-Nyeong
    • Journal of Korea Water Resources Association
    • /
    • v.30 no.4
    • /
    • pp.367-377
    • /
    • 1997
  • In order to set public policy to overcome 'water crises' on both quantity and quality of water, we looked into the national-economic role of Korea water utility by two approaches. First, we examined the relationship between water consumption and economic growth during 1978-94, a period of rapid increase in water consumption caused by prompt industrialization and urbanization. The price and income elasticities of aggregate and sectoral demand for water were estimated. Second, we developed a static input-output(I-O) framework for analysing water issues in the short run. In addition, we discussed two topics in its application: i) sectoral failure(shortage) costs by supply-driven I-O model, ii) Leontief price model's sectoral pervasive effects of price due to rise in water rate. In conclusion, we found that investments to water sector and water shortage has a big influence on the standard of living and industrial production. Also we found that raising water rate to encourage conservation or to create investment funds decreases demand for water significantly but has a small influence on overall price levels.

  • PDF