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Review of Dam-Reservoir water level considering Dam-downstream situation (직하류 하천환경을 고려한 댐 저수량 수위 확보 검토)

  • Kim, Chang-soon;Kim, Jong-Rae
    • Proceedings of the Korea Water Resources Association Conference
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    • 2017.05a
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    • pp.377-377
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    • 2017
  • 다목적댐은 비어있는 저수지 용량을 활용, 상류에서 유입되는 홍수를 저류하여 하류의 피해를 경감시키고, 저류된 저수량을 활용하여 갈수시 생 공 유지용수 등을 목적에 맞게 하류로의 공급에 주요 목적이 있다. 이를 위해 댐 계획에는 상류에서 유입되는 목표 빈도 계획홍수량을 산정하고, 이에 따른 여수로의 계획방류량 등이 포함된 홍수 조절 방안이 수립된다. 다목적댐은 그 중요도 때문에 많은 사회적 재화(財貨)가 투입되어 하천에서 가장 높은 빈도인 200년 빈도 홍수량에 대비하도록 설계되어 있다. 그러나 대부분의 댐 하류 하천에서는 긴 연장에 따른 투자비용 등의 한계로 상류 댐에 미치지 못하는 100년 빈도 이하로 설정되어있다. 이런 상 하류의 홍수계획간 괴리로 댐의 계획 방류량 수준의 홍수 조절시에는 하류 하천에 재난상황으로 발생할 우려가 있다. 기상예보의 고도화로 단기 예보의 정밀도가 높아져 단기간 댐 운영에는 효과적으로 활용되고 있다. 하지만 5일 이후를 예보하는 중 장기예보는 아직까지도 불확실성이 높은 실정이다. 여기에 기후변화 등 기상의 불확실성을 고려하여 홍수기 초 장마와 태풍 등의 영향에 대비하기 위해 무작정 댐을 저(低)수위로 운영하면 이후 여름 가뭄에 취약해 지고, 반대로 저수량 확보의 고(高)수위 운영을 할 경우 연이은 태풍 등 홍수상황에 취약해 지게 된다. 최근 '14~'15년도 낙동강 수계에 여름가뭄으로 안동 임하댐이 가뭄단계에 돌입하는 등 홍수기초 적정 저수량의 확보는 안정적 수자원시설 운영에 중요성이 커지고 있다. 본 연구에서는 이러한 불확실한 기상상황에 대비하고 댐의 이치수 목적 달성을 위해, 홍수기초 가능한 저수량을 확보하되 계획홍수량이 들어와도 하류피해는 경감시킬 수 있는 저수지 수위를 찾고자하였다. 이를 위해 낙동강 수계 9개 다목적댐(안동, 임하, 성덕, 보현산, 군위, 김천부항, 합천, 남강, 밀양댐)을 대상으로 댐 설계 및 직하류 하천 상황을 고려한 "홍수기초 댐 저수량 확보 수위 검토"를 실시하였다. 댐 직하류 하천의 홍수대비 상황 및 홍수조절시 제약사항 등을 조사해 주요지점(Critical Point)을 선정하고 그 지점의 홍수량을 파악한다. 이어서 저류함수 모형을 활용하여 댐별 저수지 모의 운영을 실시하였다. 대상 댐 저수지에 계획홍수량을 유입시키고 수위를 점차 조정하면서 하류 지점의 홍수량 내의 규모로 방류를 하는 저수지 모의 운영을 실시하였다. 이때 저수지의 계획홍수위를 초과하지 않는 등 안정적 홍수조절이 가능한 특정 수위를 찾아 하류 하천 환경을 고려한 댐 운영 수위로 선정하였다. 최근 홍수기총에는 강수량이 계속 줄어들고 홍수기 이후 더 많은 강수가 내리는 등 기후변화로 댐 운영은 날로 어려워지고 있다. 본 연구의 분석 결과는 홍수기초 가뭄 및 장마 또는 태풍 등에 대비하여 댐 운영의 이 치수 두 가지 목적을 달성하는데 참고가 될 수 있을 것이다.

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Effects of Roasted Korean Oak Chip Addition on the Aging of Red Wine (국산 참나무편의 첨가가 적포도주의 숙성에 미치는 영향)

  • Lee, A-Rong;Park, Heui-Dong
    • Food Science and Preservation
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    • v.18 no.6
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    • pp.891-897
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    • 2011
  • Oak barrel have been used for a long time for the aging of wine. Instead of oak barrel aging, however, roasted oak chips can be directly added in the wine before aging. In this study, Korean oak chips roasted for different time durations were used for the red wine aging, and the properties of wine aged through the addition of the roasted oak chips were characterized. No significant differences were observed in the alcohol, soluble-solid, reducing-sugar and total-acid contents based on the oak chips aging, but the total phenol content increased. The methanol, ethyl acetate, propanol, isobutanol and isoamyl alcohol contents also increased. Especially, the methanol and propanol contents increased as the roasting time was prolonged. Although the hue values were similar to one another, the intensity as well as the lightness, redness, and yellowness values were high in the wine aged with the roasted oak chips. In the sensory evaluation, the wine aged with oak chips roasted for 2 h showed the highest scores in the flavor, taste, and overall preference.

Development of Mobile-Based Design Value Engineering(VE) Supporting System for VE Process Improvement (VE프로세스 개선을 위한 모바일 기반의 설계VE 시스템 개발)

  • Song, Chang-Young;Yang, Byong-Soo
    • Journal of the Korea Institute of Building Construction
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    • v.21 no.5
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    • pp.433-443
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    • 2021
  • Value Engineering(VE) is an organized effort to create the most value through a functional analysis and creation of alternatives. Depending on the VE job plan, a VE Workshop must be performed in a certain place within a certain period of time. A VE Workshop, which is an organized activity that aims to create the best value through functional analysis and creation of alternatives, should be held in a certain place and at a scheduled time according to the VE job plan. In the Pre-Study, VE Study and Post-Study phases of VE, functional assessments, performance evaluations and idea evaluations are driven by variable management techniques and analysis methods, respectively. Generally, VE is executed for about 3 to 5 days in a particular place to create value. However, there are many problems associated with limiting all VE processes to a specific place and schedule. Moreover, in Korea, VE teams are required to finish all VE processes in a limited time because of the short duration of VE workshops, the necessity of which has been overlooked. Therefore, an efficient VE support system is required to resolve the problem of time and space limitations. In this study, a VE support system based on the Mobile environment was developed to support the VE Workshop process. This VE support system enables participants to review design documents, drawing sheets and all VE-related documents using mobile devices. After the Workshop, participants can conveniently rearrange the result(evaluation of function and ideas) at the workshop. Not only can the members of VE team can review the design documents, drawing sheet and all VE-related documents in the step before the workshop, but also the result(evaluation of function and ideas) of the workshop can be easily rearranged in the phase after the workshop under the developed supporting system using mobile devices.

사학연금 실업급여를 대비한 재해보상급여 활용방안 연구

  • Jeong, In-Yeong;Gwon, Hyeok-Chang;Kim, Su-Seong
    • Journal of Teachers' Pension
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    • v.4
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    • pp.175-205
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    • 2019
  • 본 연구의 목적은 폐교로 인해 퇴직한 사립학교 교직원을 대상으로 사학연금의 재해보상기금을 활용하여 실업급여를 제공하는 방안을 모색하는데 있다. 이를 위해 먼저 폐교 퇴직 교직원 현황 및 사학연금에서 폐교로 인한 퇴직 시 연금 지급규정, 재해보상 관련 쟁점, 고용보험 임의가입방안 관련 쟁점 등에 대해 고찰하였다. 다음으로 폐교로 인한 퇴직 교직원에 대한 정책방안들로 현행안, 재해보상기금을 활용한 구직급여 제공방안, 고용보험 임의가입안에 대한 재정추계를 실시하였다. 주요 분석결과는 다음과 같다. 첫째, 불과 5년 뒤인 2024학년도부터는 대입가능자원이 대학입학정원을 크게 밑돌 것으로 전망되고 이로 인해 대학의 통·폐합과 구조조정 등이 발생하여 현재보다 훨씬 더 많은 대학이 폐교될 것으로 예상된다. 둘째, 현행 사학연금법 상연금지급개시연령은 65세이나, 공무원연금법을 준용하고 있는 사학연금에서 폐교로 인해 퇴직하는 경우 퇴직 때부터 5년이 경과한 때 연금을 지급하는 규정으로 인해 여러 문제점들이 발생하고 있다. 셋째, 폐교로 인한 비자발적 퇴직 교직원의 소득활동 중단에 따른 소득 대체 및 생활안정을 위한 방안마련이 시급하다. 넷째, 산재보험과 공무원연금·군인연금 등 공적 재해보상제도들은 모두 업무상 또는 공무상 사고나 질병으로 부상·질병·장해·사망이 발생하면 재해로 정의하고 있어 사학연금에서 폐교를 재해로 포함시키는 것은 적합하지 않으며, 실업에 대응하는 사회보장제도인 고용보험에 포함시키는 것이 보다 타당할 것으로 보인다. 다섯째, 사립학교 교직원에 대한 고용보험적용 여부를 논의하기 위해서는 대학교수의 법적 지위와 근로기준법의 적용가능성이 중요한데, 향후 대법원이 대학교수를 근로기준법상 근로자로 판단한다면 사학 교직원의 고용보험 가입도 가능하게 될 것이다. 여섯째, 사학연금가입자들을 위한 고용보험 도입이 바람직하나, 이것이 단기간 내에 실행되기 어렵다면 고려 가능한 대안으로 공무원연금과는 다른 사학 교직원 직무에서 발생하는 재해의 특성을 고려하여 사학재해보상제도에서 폐교로 인한 퇴직을 재해보상에 포함시키고 구직급여를 제공하는 방안을 검토해 볼 수 있다. 또한 재정추계결과는 다음과 같다. 첫째, 현재 폐교로 인한 퇴직 시 제공되는 연금 대신에 재해보상기금으로 구직급여를 제공할 경우 사학연금기금에 재정적으로 상당히 긍정적 효과가 있을 것으로 예상된다. 둘째, 폐교로 인한 2018년 현재 연금수급자(285명)의 예상 연금급여액 추계에 의하면 2050년까지 누적해서 볼 경우, 재해보상기금을 활용하여 구직급여를 제공하는 방안이 폐교로 인한 퇴직 시 연금을 지급하는 현행안보다 2018년 현재가치로 123억 원 정도 유리한 것으로 나타났다. 셋째, 현재 수급자와 미래 수급자의 예상 연금급여액 추계에 의하면 2028년까지 누적해서 볼 경우, 재해보상기금을 활용하여 구직급여를 제공하는 방안이 현행안보다 2018년 현재가치로 747억 원 정도 재정적으로 유리한 것으로 나타났다.

Changes in Physicochemical Properties of Low Salt Soybean Paste (Doenjang) during Fermentation (저염 된장 발효 중 이화학적 특성 변화)

  • Lee, Ju-Yeon;Mok, Chulkyoon
    • Food Engineering Progress
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    • v.14 no.2
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    • pp.153-158
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    • 2010
  • Changes in physicochemical properties of soybean pastes (Doenjang) of various salt contents (8-14%) during fermentation were investigated to explore the possibility of manufacturing a low salt soybean paste. Titratable acidity (TA) increased and consequently pH decreased with the fermentation time. The rates of TA and pH changes increased as the salt levels decreased. Protein contents remained unchanged and there were no differences among different salt levels. The amino nitrogen contents and the volatile basic nitrogen contents increased with fermentation time and showed higher values at lower salt levels. The reducing sugar contents increased from 6th to 11th week of fermentation, and decreased afterward. No remarkable differences in the reducing sugar contents were observed with respect to salt levels. Shorter fermentation periods were required at reduced salt levels. Appropriate fermentation periods of the 8, 10, 12 and 14% salt containing Doenjang were 2 to 11 weeks, 3 to 12 weeks, 6 to 14 weeks, and 9 to 15 weeks, respectively. Doenjang fermented for shorter period of time at lower salt content showed better sensory quality than that for longer period at higher salt content.

Analysis of Membrane Fouling Reduction by Natural Convection Instability Flow in Membrane Filtration of Protein Solution Using Blocking Filtration Model (막힘여과 모델에 의한 단백질 용액의 막여과에서 자연대류 불안정 흐름의 막오염 제어 효과 해석)

  • Kim, Ye-Ji;Youm, Kyung-Ho
    • Membrane Journal
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    • v.29 no.1
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    • pp.18-29
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    • 2019
  • The dead-end ultrafiltration (UF) of BSA protein solution was performed to investigate the defouling effects of natural convection instability flow (NCIF) induced in membrane module. The permeate fluxes were measured according to the inclined angles ($0{\sim}180^{\circ}$) of membrane module with respect to gravity, and analyzed using the blocking filtration model. NCIF are more induced as the inclined angles increased from $0^{\circ}$ to $180^{\circ}$, and the induced NCIF enhances flux. Comparing the fluxes at $0^{\circ}$ inclined angle (no NCIF induction) and $180^{\circ}$ (maximum NCIF induction), the flux enhancements by NCIF induction are increased about 5 times in the short-term UF operation (2 hours) and about 17 times in the long-term operation (20 hours). As applying the blocking filtration model, it is more suitable to analyze the flux results by using the intermediate blocking model in the early times of UF operation within 15 minutes and then thereafter times by using the cake filtration model. NCIF induced at $180^{\circ}$ inclined angle reduces the intermediate blocking fouling at about 67% in the early times operation and thereafter the cake layer fouling at about 99.9%. The main defouling mechanism of NCIF induced in the membrane module is suppress the formation of protein cake layer.

The Relationship between Obesity and Cardiac Autonomic Regulation in College-Aged Male Smokers (남자흡연대학생의 비만과 심장자율신경조절의 관련성)

  • Kim, Choun Sub;Kim, Maeng Kyu
    • Journal of the Korean Applied Science and Technology
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    • v.36 no.1
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    • pp.142-152
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    • 2019
  • This study aimed to explore the association between obesity index and heart rate variability (HRV) in college-aged male smokers. A total of 85 male college students (> 10 cigarettes per day for at least 3 years) were participated in this study. According to a standardized protocol, body mass index (BMI), percent body fat (%BF), waist circumference (WC), and waist-to-hip ratio (WHR) were taken as obesity indices. Resting r-r interval was monitored for HRV analysis as an indicator of cardiac autonomic regulation. Compared with low WHR subjects, high WHR subjects had significantly lower values of rMSSD, pNN50, HF, and SD1, suggesting decreased parasympathetic activity. No such differences in LF/HF ratio were found between the WHR-based subgroups. Bivariate correlation analysis showed that obesity indices of WC, WHR, and %BF were significantly associated with rMSSD, pNN50, HF, and SD1, with a tendency for correlation coefficient to be higher with WHR than with WC or %BF. No significant association was found between BMI and HRV parameters indicative of parasympathetic activity. This study suggest that central obesity is significantly associated with decrease in parasympathetic activation, independent of BMI as an indicator of obesity, in male college smokers.

Phylogenetic Diversity and Antibacterial Activity of Bacteria from Shindari of Jeju Traditional Fermented Food (제주 전통 발효식품 쉰다리에서 분리한 세균의 군집 조사 및 어류질병세균과 인체유해세균에 대한 항균활성효과)

  • Ryu, Young-Soo;Heo, Moon-Soo
    • Journal of Life Science
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    • v.31 no.1
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    • pp.73-82
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    • 2021
  • Throughout history, barley was the typical crop of the soils of Jeju Island due to its topographical features. People in Jeju eat Shindari or Dansul. Shindari or Dansul is a fermented drink of Jeju, made from the leftovers of cooked barely and nuruk of short fermentation periods. Although Makgeolli and Shindari share a similar fermentation period and materials, research on Shindari or Dansul is still in its early stages. In this study, we examined major bacterial species of Shindari or Dansul. In addition, we confirmed the antibacterial activities of an isolated strain against fish and human-harmful bacteria. Among the isolates, Firmicutes consisted of 73% and the Proteobacteria of 27%, indicating that the Firmicutes phylum was the dominant one. In addition, the Pediococcus genus and the Bacillus genus were the most prevalent consisting of 25%, followed by the Cronobacter genus (25%), the Enterococcus genus (16%), the Aneurinibacillus genus (5%), the Klebsiella genus (4%), and the Paenibacillus genus (2%). We conclude that the Lactobacillus genus predominated in Makgeolli, but the Pediococcus genus predominated in Shindari. In a study of the antibacterial activity, growth inhibition was observed for all bacteria, except for the fish disease bacterium Photobacterium damselae subsp. piscicida and the human-harmful bacterium Streptococcus mutans.

Analysis of Perceptions on Accreditation System of Vocational Training Providers and Measures to Improve the Accreditation System (직업훈련기관 인증평가에 대한 인식 및 개선방안 연구)

  • Ko, Hye-Won;Lee, Chul-Soon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.2
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    • pp.694-704
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    • 2021
  • To improve the quality of government-funded vocational training, an accreditation system of vocational training providers has been implemented since 2015. The purpose of this study was to suggest improvement measures by analyzing the accreditation system and the perceptions surrounding it. To this end, accreditation systems from European countries, such as Germany and the UK, as well as related domestic systems, were reviewed. Two surveys were administered to 131 appraisers and 370 vocational training providers. The study results showed that changes to the standard and accreditation processes are not needed at this point. In the long term, however, it will be necessary to request that vocational training providers adopt their quality assurance system. In addition, both appraisers and vocational training providers responded that the accreditation system is being established to increase the quality assurance system within vocational training providers. Based on the study results, several implications for improving the accreditation system were suggested as follows: a vocational training enhancement centered on outstanding vocational training providers; an accreditation system simplification for short-term vocational training providers; a stronger monitoring system during the accreditation period; and an operation of outcome-based accreditation.

Geochemical Modeling on Water-caprock-gas Interactions within a CO2 Injected in the Yeongil Group, Pohang Basin, Korea (포항분지 영일층군 내 이산화탄소 주입에 의한 물-덮개암-가스 반응에 대한 지화학적 모델링)

  • Kim, Seon-ok;Wang, Sookyun;Lee, Minhee
    • Economic and Environmental Geology
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    • v.54 no.1
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    • pp.69-76
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    • 2021
  • This study is to identify the mineralogical properties of caprock samples from drilling cores of the Pohang basin, which is the research area for the demonstration-scale CO2 storage project in Korea. The interaction of water-rock-gas that can occur due to CO2 injection was identified using geochemical modeling. Results of mineralogical studies, together with petrographic data of caprock and data on the physicochemical parameters of pore water were used for geochemical modeling. Modelling was carried out using the The Geochemist's Workbench 14.0.1 geochemical simulator. Two steps of modeling enabled prediction of immediate changes in the caprocks impacted by the first stage of CO2 injection and the assessment of long-term effects of sequestration. Results of minerlaogical analysis showed that the caprock samples are mainly composed of quartz, K-feldspar, plagioclase and a small amount of pyrite, calcite, kaolinite and montmollonite. After the injection of carbon dioxide, the porosity of the caprock increased due to the dissolution of calcite, and dawsonite and chalcedony were precipitated as a result of the dissolution of albite and k-feldspar. In the second step after the injection was completed, the precipitation of dawsonite and chalcedony occurred as a result of dissolution of calcite and albite, and the pH was increased due to this reaction. Results of these studies are expected to be used as data to quantitatively evaluate the efficiency of mineral trapping capture in long-term storage of carbon dioxide.