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Channel Evaluation for Abandoned Channel Restoration Using Image Analysis Technique (영상분석기법을 이용한 구하도 복원 대상하천의 하도평가)

  • Hong, Il;Kang, Joon-Gu;Kwon, Bo-Ae;Yeo, Hong-Koo
    • Journal of Korea Water Resources Association
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    • v.42 no.5
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    • pp.397-406
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    • 2009
  • River is able to change by various environmental factors. In order to conduct restoration design of abandoned river channels, it is necessary to evaluate the river through the analysis of past and present river channels. River evaluation requires various data, such as geometry, hydraulic and hydrology, but there is a lot of difficulty to understand topographical information of river change on time and space due to a lack of past data by domestic conditions. This study analyzes the changes in past and present river channels and examines the applicability of river channel evaluation through image analysis using aerial photographs and 1918 year's map. Aerial photograph analysis was conducted by applying the image analysis method and GIS analysis method on Cheongmicheon. As a result of this analysis, we have quantitatively identified the form and size of abandoned channels, changes in the vertical-section and cross-section length of rivers, and micro-landform changes. More importantly, we verified that morphological changes in sandbars due to artificial straightening are important data in identifying the state of current river channels. In these results, although image analysis technique has limitations in two-dimensional information from aerial photographs, we were able to evaluate the changes in river channel morphology after artificial maintenance of the river.

Application of Chiu's Two Dimensional Velocity Distribution Equations to Natural Rivers (Chiu가 제안한 2차원 유속분포식의 자연하천 적용성 분석)

  • Lee, Chan-Joo;Seo, Il-Won;Kim, Chang-Wan;Kim, Won
    • Journal of Korea Water Resources Association
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    • v.40 no.12
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    • pp.957-968
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    • 2007
  • It is essential to obtain accurate and highly reliable streamflow data for quantitative management for water resources. Thereafter such real-time streamflow gauging methods as ultrasonic flowmeter and index-velocity are introduced recently. Since these methods calculate flowrate through entire cross-section by measuring partial velocities of it, rational and theoretical basis are necessary for accurate estimation of discharge. The purpose of the present study lies in analysis on the applicability of Chiu#s(1987, 1988) two dimensional velocity distribution equations by applying them to natural rivers and by comparing simulated velocity distributions with observed ones obtained with ADCP. Maximum and mean velocities are calculated from observed data to estimate entropy parameter M. Such isovel shape parameters as h and $\beta_i$ are estimated by object function based on least squares criterion. In case optimized parameters are applied, Chiu#s velocity distributions fairly well simulate observed ones. By using 14 simulated data sets which have relatively high correlation coefficients, properties of parameters are analyzed and h, $\beta_i$ are estimated for velocity-unknown river sections. When estimated parameters are adopted for verification, simulated velocity distributions well reproduce real ones. Finally, calculated discharges display rough agreement with measured data. The results of the present study mean that if parameters related are properly estimated, Chiu#s velocity distribution is likely to reproduce the real one of natural rivers.

A Study on the Characteristics of Plan Composition shown in the Public Space of the Luxury Tourist Hotels on Seogwipo-si (서귀포시 특급관광호텔 공용공간에서 나타나는 평면구성의 특징에 관한 연구)

  • Kang, Bong-Yu;Park, Chul-Min
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.2
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    • pp.501-510
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    • 2016
  • Because hotels contain the cultural and artistic information of an era and plays a role as an iconic building to experience the unique regional culture, they are more than just a building. In recent years, as Jeju is emerging as a popular tourist city, a multi-functional and systematic plan for hotels is needed. Therefore, this study provides basic design data for hotel construction in the future by analyzing the public space of the luxury tourist hotels on Seogwipo-si. The public space of hotels, divided into service, food and beverage, banquet, leisure and convenience space, are categorized in terms of the cross combination type, entrance space form, plan type, unit space form to understand their relativity in the public space of hotels. This study reviewed the hotel construction based on the reference and literature, and, visited the sites to determine the current general status of hotels and then analyzed the architectural planning factors and spatial composition types.

Blood Pressure and Dietary Related Risk Factors Associated with High Sodium Intake Assessed with 24-hour Urine Analysis for Korean Adults (한국 성인들의 24시간 소변 분석법에 근거한 고나트륨군의 혈압과 고나트륨 섭취관련 위험인자에 관한 연구)

  • Jeong, Yeon-Seon;Lim, Hwa-Jae;Kim, Sook-Bae;Kim, Hee Jun;Son, Sook Mee
    • Korean Journal of Community Nutrition
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    • v.19 no.6
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    • pp.537-549
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    • 2014
  • Objectives: This study was conducted to examine blood pressure and other characteristics of a high sodium intake group assessed with 24-hr urine analysis and the dietary factors related to the risk of high sodium intake among Korean adults. Methods: A cross-sectional study was conducted with adults aged 20-59 years. Subjects who completed 24-hr urine collection (N = 205) were divided into 3 groups (tertile) according to the sodium intake estimated with 24-hour urine analysis. We compared the blood pressure, BMI and dietary related factors of the 3 groups (low, medium, high sodium intake group) with General Linear Model (GLM) and Duncan's multiple range test (p < 0.05). The risk factors related to high sodium intake were assessed with odds ratio (p < 0.05). Results: The sodium intake (mg/day) of the 3 groups were $3359.8{\pm}627.9$, $4900.3{\pm}395.1$ and $6770.6{\pm}873.9$, respectively, corresponding to daily salt intake (g/day) 8.5, 12.4 and 17.2, respectively. High sodium group showed significantly elevated age, BMI and systolic/diastolic blood pressure. Being male gender was associated with significantly increased risk of sodium intake (OR = 1.972; 95%CI: 1.083-3.593). The other factors related to high sodium intake were higher BMI (${\leq}25$) (OR = 2.619; 95% CI: 1.368-5.015), current alcohol consumption (OR = 1.943; 95%CI: 1.060-3.564), and having salty soybean paste with salt percentage > 14% (OR = 3.99; 95% CI: 1.404-6.841). The dietary attitude related to increased risk of high sodium intake included 'enjoy dried fish and salted mackerel' (p < 0.001) and 'eat all broth of soup, stew or noodle' (p < 0.001). Conclusions: Because high sodium intake was associated with higher blood pressure, nutrition education should focus on alcohol consumption, emphasis on related dietary factors such as using low salt soybean paste, improvements in the habit of eating dried fish and salted mackerel or eating all broth of soup, stew or noodle.

Information in the Implied Volatility Curve of Option Prices and Implications for Financial Distribution Industry (옵션 내재 변동성곡선의 정보효과와 금융 유통산업에의 시사점)

  • Kim, Sang-Su;Liu, Won-Suk;Son, Sam-Ho
    • Journal of Distribution Science
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    • v.13 no.5
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    • pp.53-60
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    • 2015
  • Purpose - The purpose of this paper is to shed light on the importance of the slope and curvature of the volatility curve implied in option prices in the KOSPI 200 options index. A number of studies examine the implied volatility curve, however, these usually focus on cross-sectional characteristics such as the volatility smile. Contrary to previous studies, we focus on time-series characteristics; we investigate correlation dynamics among slope, curvature, and level of the implied volatility curve to capture market information embodied therein. Our study may provide useful implications for investors to utilize current market expectations in managing portfolios dynamically and efficiently. Research design, data, and methodology - For our empirical purpose, we gathered daily KOSPI200 index option prices executed at 2:50 pm in the Korean Exchange distribution market during the period of January 2, 2004 and January 31, 2012. In order to measure slope and curvature of the volatility curve, we use approximated delta distance; the slope is defined as the difference of implied volatilities between 15 delta call options and 15 delta put options; the curvature is defined as the difference between out-of-the-money (OTM) options and at-the-money (ATM) options. We use generalized method of moments (GMM) and the seemingly unrelated regression (SUR) method to verify correlations among level, slope, and curvature of the implied volatility curve with statistical support. Results - We find that slope as well as curvature is positively correlated with volatility level, implying that put option prices increase in a downward market. Further, we find that curvature and slope are positively correlated; however, the relation is weakened at deep moneyness. The results lead us to examine whether slope decreases monotonically as the delta increases, and it is verified with statistical significance that the deeper the moneyness, the lower the slope. It enables us to infer that when volatility surges above a certain level due to any tail risk, investors would rather take long positions in OTM call options, expecting market recovery in the near future. Conclusions - Our results are the evidence of the investor's increasing hedging demand for put options when downside market risks are expected. Adding to this, the slope and curvature of the volatility curve may provide important information regarding the timing of market recovery from a nosedive. For financial product distributors, using the dynamic relation among the three key indicators of the implied volatility curve might be helpful in enhancing profit and gaining trust and loyalty. However, it should be noted that our implications are limited since we do not provide rigorous evidence for the predictability power of volatility curves. Meaning, we need to verify whether the slope and curvature of the volatility curve have statistical significance in predicting the market trough. As one of the verifications, for instance, the performance of trading strategy based on information of slope and curvature could be tested. We reserve this for the future research.

A Study on the Recognition of Students of Oriental Medical School on Cooperative System between Oriental and Western Medicine (한양방 협진에 대한 한의대생들의 인식도)

  • Yoo, Wang-Keun;Kim, Kyung-Suk
    • Journal of Society of Preventive Korean Medicine
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    • v.9 no.2
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    • pp.77-91
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    • 2005
  • The purpose of this study is to examine the recognition of the student of oriental medical school on cooperative system between Oriental and Western medicine and to provide basic information for the development of oriental medicine. In order to look at the level of recognition on cooperative system between Oriental and Western medicine, from September 1st to 15th of 2005, this study had been conducted through personal interview and questionnaires to 600 students who were attending the Department of Oriental Medicine (in both prep and regular courses) in D University, located in the City of Daegu. The data has been analyzed using statistic program, the SPSS WIN 12.0. Statistical analysis tools used for this study were frequency analysis, cross-over analysis and the t-test. The results are as follows; The students of oriental medical school had relatively high level of recognition on the basic concept, interests, necessity and potential for cooperative system between Oriental and Western medicine. However, they had negative understandings on the issue of unification of the two medical systems and it's possibility in the future. The students were optimistic about possible merits of cooperative system between Oriental and Western medicine, especially in the field of rehabilitation. On the reasons for lack of development of cooperative system between Oriental and Western medicine, the students listed prejudices existing on both sides firstly, followed by their contrasting approach on human illness, lack of legal and institutional support system, the indifferences of doctors and indifferences of oriental medical doctors. In addition, students understood that the dualism existing in our current medical system is aggravating mutual distrust between the two sides, causing the confusion of patients on the choice of medical facilities, and raising their medical bills. Therefore, in order to vitalize collaboration between Oriental and Western medicine in new health care environment, the following measures should be needed decreasing the prejudices between the two medical spheres with open mind improving educational programs in Western and Oriental medical schools; promoting joint academic research or exchange programs between the schools, and increasing government effort to minimize legal and institutional restrictions cooperative system between Oriental and Western medicine.

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Bioequivalence of Two Nilvadipine Tablet (닐바디핀 정제에 대한 생물학적 동등성 평가)

  • 김종국;이사원;최한곤;고종호;이미경;김인숙
    • Biomolecules & Therapeutics
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    • v.6 no.3
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    • pp.289-295
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    • 1998
  • The bioequivalence of two nilvadipine products was evaluated in 16 normal male volunteers (age 22-32 yr, body weight 57-80 kg) following sidle oral dose. Test product was Overca $l_{R}$ tablet (Choong-Wae Pharm. Corp., Korea) and reference product was Nivadi $l_{R}$ tablet (Hyundai Pharm. Corp., Korea). Both products contain 4 mg of nilvadipine. One tablet of the test or the reference product was administered to the volunteers, respectively, by randomized two period cross-over study (2$\times$2 Latin square method). The determination of nilvadipine was accomplished using a validated capillary column GC with electron-capture detection. As a result of the assay validation, the quantiflcation of nilvadipine in human plasma by this technique was possible down to 0.5 ng/ml using 1 ml of plasma. Absolute overall recovery from five replicate analyses of nilvadipine-spiked sample were 88.4$\pm$ 10.24% (mean$\pm$ 5.D.) for human plasma of 10 ng/ml. The coefficients of variation (C.V.) were less than 20% and the actual concentration of nilvadipine measured by GC ranged from 80 to 99% in all plasma. Average drug concentrations at each sampling time and pharmacokinetic parameters calculated were not significantly different between two products (p>0.05); the area under the curve from time zero to 8 hr (AUCo-$_{8 hr}$) (22.8$\pm$5.90 vs 22.2$\pm$6.10 ng . hr/ml), maximum plasma concentration ( $C_{max}$) (10.0$\pm$2.85 vs 9.3$\pm$3.28 ng/ml) and time to reach maximum plasma concentration ( $T_{max}$) (1.2$\pm$0.31 vs 1.3 $\pm$0.47 hr). The differences of mean AU $Co_{8hr}$ $C_{max}$, and $T_{max}$ between the two products (2.25, 7.65, and 10.30%, respectively) were less than 20%. The power (1-$\beta$) and treaeent difference (7) for AU $Co_{8hr}$, and $C_{max}$ were more than 0.8 and less than 0.2, respectively. Although the power for Tmax was under 0.8, Tm\ulcorner of the two products was not significantly different from each other (p>0. 05). These results suggest that the bioavailability of Overeat tablet is not significantly different from that of Nivadil tablet. Therefore, two products are bioequivalent based on the current results.sults.lts.lts.lts.

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A Study of the Obesity Index and Psychosocial Factors Influencing Obesity among Adolescent Girls (여고생들의 비만도 및 비만과 관련된 사회심리적 요인 분석)

  • 김경원;김영아;김정희
    • Korean Journal of Community Nutrition
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    • v.2 no.4
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    • pp.496-504
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    • 1997
  • The purpose of this study was to investigate the dietary intake, obesity index and psychosocial factors influencing obesity among 200 high school girls in Seoul. The Social Cognitive Theory provided the Conceptual basis for this study. A cross-sectional survey was conducted to examine factors related to obesity, including self-efficacy for controlling overeating, social support for eating behavior, perception of body image and weight control, nutrition knowledge, and attitudes toward obesity. The data were analyzed using t-test and multiple logistic regression. The results of this study are as follows : 1) The mean age of the girls was 16.4 years, and the rate of overweight and obesity(measured by obesity index) was 27.0$\%$. 2) The mean energy intake of subjects was 1832.3$\pm$384.0kcal. The energy derived from carbohydrates, proteins and fats was 62.7$\%$, 13.8$\%$, and 23.5$\%$, respectively. There was no significant difference between the obese and the comparison group in energy intake. 3) The result of multivariate analysis indicated that obesity had a significant relation to the perception of ideal body image, social support for eating behavior, and self-efficacy for controlling overeating(p〈0.01). As subjects preferred thinner body images(OR=0.39) and received less social support(OR=0.93), the odds of being classified as obese increased. The odds of being obese were also associated with self-efficacy, however, the relation was not strong(OR=1.04). 4) Specific social support was related to obesity among adolescent girls. As subjects received more support from family member, the odds of being obese decreased. The emotional support as well as family member's positive nutrition behavior plays a significant role. In addition, instrumental support from friends was associated with obesity. With repect to self-efficacy, the odds of being obese were increased as subjects felt less confident in controlling overeating when tempting food was placed in front of them or after an argument. In contrast, the obese group felt more confident in controlling overeating for the rest of the specific situations examined. These findings suggest that educational interventions for weight control should incorporate strategies to help participants realize their degree of obesity, to reduce the discrepancy between current and ideal body image, to elicit and maintain social support from friends and family, and to increase the self-efficacy for changing eating behaviors. (Korean J Community Nutrition 2(4) : 496-504, 1997)

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Effects of Ocean Outfall for Elimination of the Anoxic Layer in Youngsan River Estuary (영산강 하구언에서 저 산소 층의 제거를 위한 해양방류구의 효과)

  • Kwon, Seok-Jae;Cho, Yang-Ki;Seo, Uk-Won
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.17 no.4
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    • pp.259-268
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    • 2005
  • There has been a growing interest in the elimination of anoxic layer in the Youngsan River Estuarybecause the anoxic water mass caused mainly by the inflow of fresh water from the sea wall might cause the mass reduction of benthos during summer. An ocean outfall system to discharge treated wastewater into sea water may be used as one of the effective and economical ways to eliminate the anoxic layer. The suitable ocean outfall design is generally proposed for the prediction of the buoyant jet behavior in the near field. The parameters including CTD and current data are taken into account f3r more reliable buoyant jet behavior calculation. One of the numerical models, CORMIX 1, approved by EPA is used herein for the prediction of the trajectorial variation of the cross-sectional salinity and DO concentration distribution on the calculated buoyant jet boundary according to the tidal periods. On the basis of the results, it is suggested that the single port outfall is a useful system to eliminate the anoxic layer. Proper strategies are also proposed for achieving desirable ambient conditions.

Cervical Cancer Prevention for the Future: the Complimentary Roles of Cytology Screening and HPV Vaccination (자궁경부암 예방의 미래 : 세포선별검사와 HPV 예방접종의 역할)

  • McGoogan, Euphemia
    • The Korean Journal of Cytopathology
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    • v.18 no.1
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    • pp.1-12
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    • 2007
  • Approximately 70% of cervical cancers are caused by HPV types 16/18 and thus the implementation of vaccination programmes with vaccines against HPV types 16/18 will have a major impact on the incidence of cervical cancer worldwide. However, this reduction will not be seen until several decades after full implementation of such vaccination programmes since the vaccines must be given to young adolescents before exposure to the virus and women who are already sexually active are not likely to be protected. Both GSK and Merck insist that even vaccinated women must continue to participate in regular cervical screening by the most sensitive method available since the vaccine can only give protection against up to 70% of cervical cancers. It is unlikely that the current vaccines will be modified to include additional high risk HPV types in the foreseeable future. While HPV testing is highly sensitive, it is not recommended for women under 30 years of age nor for vaccinated women. Additionally, HPV testing has poor specificity. The Digene Hybrid Capture 2 test is licensed for use only in conjunction with a cytology test, not as a stand-alone test, and the high risk panel has recognised cross reactivity with low risk HPV types. None of the other HPV test methods currently commercially available are FDA approved and all must be internally validated before use. This makes comparison of test results between laboratories difficult. The most sensitive and specific screening test currently available for women of all ages is the Cytyc ThinPrep System consisting of the ThinPrep Pap Test (TPPT) and the ThinPrep Imaging System (Imager). The TPPT was the first LBC system approved by the US FDA in 1996 and there are about 4,000 processors in use worldwide. The Imager was FDA approved in 2003 and over 350 systems are in routine use, mainly in the US. 40% of TPPT in the US are processed on Imager. There is clear evidence in peer reviewed literature that the Imager increases laboratory productivity by 100% and growing evidence that Imager detects more high grade SIL than the conventional smear or manual evaluation of TPPT. This aspect is particularly important since the number of cytological abnormalities will decrease as vaccination programmes are implemented. Cytotechnologists will see fewer and fewer abnormal smears and their skills will be put at risk. By doubling throughput, Imager will allow cytotechnologists to maintain their skills.