• KSCE Journal of Civil and Environmental Engineering Research
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• v.42 no.2
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• pp.171-179
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• 2022

In this study, the characteristics of algae mitigation according to dam operation were quantitatively analyzed for Uiam Lake, where the Chuncheon Dam is located upstream of the main stream, Uiam Dam is located downstream, and Soyang Dam is located in the tributary stream. Nine dam operation scenarios were applied to the event of the summer of 2018 (at that time an algae alert occurred) using the EFDC model, which is capable of calculating three-dimensional hydrodynamics and water quality levels such as those associated with chlorophyll-a. The dam operation scenarios were set to generate a flushing effect via discharges in the form of pulse waves from the upstream dams and by lowering the water level at the downstream dam. At Uiam Lake, the flushing effect was different depending on the operation of the dam, and the amount of algae reduction at each point was different owing to topographic characteristics and the different base water temperatures from BukHan River and Soyang River. With regard to a point located on the left bank, it was predicted that the peak level of chlorophyll-a would be reduced by approximately 50 % or more upon pulsed discharge at 50 m³/s for three days at Soyang Dam. However, for the right bank, the amount of discharge from Soyang Dam had little effect on algae mitigation. Therefore, an appropriate dam operation could be effective for algae mitigation at specific points in the water body where large dams exist upstream and downstream, such as at Uiam Lake, in an emergency situation in which algal blooms rapidly.

• Journal of the Korean Institute of Gas
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• v.22 no.3
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• pp.84-90
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• 2018

We researched the way to minimize the damage when the chlorine-leak accident take place in a purification plant. Since the level of risk based on the Off-site Risk Assessment(ORA) is a combination of proportional to the number of residents in the damaged area and frequency of accidents, we suggested the adequate conditions to reduce the number of residents in the damaged area by means of the operating temperature of a handling facility, installation of a emergency shut-off valve, and the analysis of the variation of the damaging range in accordance with the type of enclosure. The coverage of damage was calculated by the 'KORA(Korea Off-site Risk Assessment Supporting Tool) program. The research shows that the lower operating temperature gets, the more emergency shut-off valve being installed and the higher enclosure level of facility becomes, the extent of damage gets decreased. The decreasing rate of worst case was 17.6%, 71%, 34.5% respectively, the decreasing rate of alternative case was 31.6%, 69.0%, 34.8% respectively.

• Korean Parent-Child Health Journal
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• v.4 no.2
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• pp.56-72
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• 2002

Web sites on the internet are getting major resources to gain information related to child care. Though the numerous web sites deliver child care information, they have never been evaluated with criteria before. The purpose of this study is to identify existence and organization of child care portal sites and to analysis their contents, therefore to suggest guidelines for parents. The survey was conducted from Sep. 1. to Oct. 30., 2001. by means of Lycos Korea and Daum search engine and finally 45 portal sites related to child care were selected eliminating the commercial and personal homepages. The results were as follows: 1. Most of the sites(95.6%) were operated by corporations without registration(82.2%). Consultants were mostly professional (71.1%). 2. The contents were analyzed 4 categories including 19 themes. 3. Diet & Nutrition category include weaning food, breast feeding, bottle feeding and snack. The recipe and type of weaning food on months were topped(64.44%). 4. Infant Care category include bathing, sleeping, clothes, skin care and cord care. bathing method and heat of bathing water were topped(44.44%). 5. Growth & Development category was consisted of developmental characteristics, dental growth, play & exercise and learning & guidance. Developmental stage and motor development were topped (62.22%). 6. Health maintenance & promotion category was consisted of emergency care, prevention of accidents, vaccination, common pediatric disease and parental role. Care of diarrhea, constipation and fever, and precautions for vaccination were topped(48.89%).

• Journal of Korean Society of societal Security
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• v.3 no.2
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• pp.33-39
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• 2010

This study is to reduce the rate of drowning accident by using of buoyancy bag. People are exposed to the high risk of drowning accident when they have water leisure activities due to the lack of safety mind-set and shortage of safety products. In case of drowning accident, the rescue action is normally depending on the other people's assistance. Therefore, rescue activities which relyn the people doesn't improve the ratio of survival in the drowning accidents. The submarine specialists should use the buoyancy products to rescue the people in the drowning accident. The citizen can carry portable buoyancy product in the automobile as well as by hands anywhere and anytime. It will be effective rescue tool to save his/her life in the emergency. In addition, it will contribute to rescue other's life because it can be used immediately. There are 3 positive characteristics on the buoyancy bag. First, it is convenience. Documents and other stuffs can be kept in the bag. Second is safety. The material of buoyancy is placed in the inner of the bag. It is possible to float the person whose weight is 90 kg. Lastly, it is durability. It can be used long-term because the outer of the bag is made of anti-water material and anti-water zipper. As a result of performance analysis, it is evident that the buoyancy bag can be used to rescue the people in the drowning accident as a indirect rescue tool compared with the current other rescue products. It is recommended that the design of outer box and performance of buoyancy are required to be improved in order to contribute more to rescue people in the accident.

• Journal of Environmental Policy
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• v.8 no.1
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• pp.97-127
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• 2009

In Germany, North Sea and East Sea possess significant meaning in many aspects. North coast has an important economical significance to North Sea Gulf States. There are a number of harbors and manufacturing facilities in this area. Agriculture is also developed. East sea, where sea water and river water mingle. has a problem that it can not control harmful substances as fast as the North Sea due to its geographical location of being connected with the North Sea as a narrow water. To protect from big and small ship accidents and pollution sources, East Sea and North Sea have enacted HELKOM Convention and OSPAR Convention, respectively. Moreover, Denmark and Germany have made cooperation on tugboats in the occurrence of shipment accidents through the LethGer-Plan and DenGer-Plan. In 1998, after the Pallas accident that occurred near Bremen, the need to improve cooperation among each states on usable resources for ocean security has been increased in Germany. Consequently, the federal government and gulf state governments associated and organized the so called, "Havarie-Kommanando Ship Accident Measure Unit". Haravarie-Kommanando is a federal-state associated organization that deals with affairs that controls national operation and mobilization of ship accident related organizations unitively when serious ship accidents occur. Moreover, federal and state participant organizations, each shipping agencies and Wiking-Helicopers-Services, a helicopter agency, are cooperating well. Also, mutual assistance with the most prominent passenger agency called Scandlines, ARGE Kuestenschutz(Germany-Denmark shipping agency) is making progress as well.

• Journal of Korean Society for Geospatial Information Science
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• v.12 no.3 s.30
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• pp.69-78
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• 2004

Since 1995, One of the NGIS(National Geographic Information System) projects, the underground utilities project, has been finished in 2003. The 19 cities in korea for this project will use underground utilities management system using underground utilities database focusing on water and sewage system. However, special expert, technical and experience problem in computer environment has not been had in working department for water and sewage management and maintenance for each local government. The management and maintenance by underground utilities database by manual method is getting lowered a data qualify of underground utilities database because of the data omitting, error in writing and securing of the lasted database. Therefore, in this study, Application test for field workers using a mobile tool and environment analysis of wireless communication in Korea and application test of GPS receiver for mobile tools had been processed and made a mobile working environment. The efficient management and maintenance method for underground utilities database has been developed an off-line method for modification and update of database about general work which has a high working frequency because of the limitation of wireless communication environment. Also, the emergency working has been applied for on-line method.

• Journal of agricultural medicine and community health
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• v.36 no.4
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• pp.218-226
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• 2011

Objectives: Paraquat (PQ) is a widely used ionic pesticide that is fatal when ingested accidentally or for suicidal purposes. It is thought that chronic exposure of PQ is related with the development of Parkinson's disease, but epidemiological studies have not yet confirmed that theory. This study attempted to estimate the possibility of environmental PQ exposure through soil and water. Materials and Methods: We analyzed the amount of decomposed PQ solution in wet soil after exposure to ultraviolet light. An artificial rainfall condition was simulated over soil sprayed with PQ to measure the amount of eluted PQ. In addition, PQ was diluted in water from three differently rated rivers and the changes in PQ concentration were measured after ultraviolet exposure over one month. High performance liquid chromatography/ultra violet detection was used to analyze the concentrations of PQ. Results: In the method we used, the recovery rate of PQ showed a precision rate less than 5%, an accuracy greater than 88%, and the calibration equation was y=5538.8x-440.01($R^2$=0.9985). There were no significant differences in the concentrations of PQ obtained from the three specimens over a 1-week period. From the PQ-sprayed soil, the artificial rainfall conditions showed no PQ elution over a 1-month period, and there was no significant differences in PQ concentrations according to ultraviolet exposure among the three samples. Conclusions: PQ remains well adsorbed naturally in soil. However, it may still exist in an integrated state for a long time in the hydrosphere, so the possibility of PQ exposure through drinking water cannot be disqualified.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.128-128
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• 2015

본 연구는 공적개발원조 사업 중 하나로 개발도상국의 실무자 및 정책결정자의 물 관련 재해위험경감 역량 강화를 위한 교육 훈련 프로그램을 검토하고 개발하는데 목적이 있다. 특히, 물 관련 재해에 대한 구조적, 비구조적 대응방식을 균형있게 논의하고 지방정부 및 관련기관과의 협력, 지역사회기반의 재해경감정책 등 새로운 대응방식관련 교육 프로그램을 검토한다. 2000년-2006년 기간 Emergency Disasters Database (EM-DAT)에 기록된 전 세계 2,163건의 물 관련 재해는 총 29만 명 이상의 인명피해와 4,220억 달러의 재산피해를 초래하였다. 이런 재해는 개발도상국이나 선진국 모두에게 치명적이지만 특히 재해대응역량이 부족한 개발도상국에 막대한 손실을 초래하여 국가개발과 존망에 큰 위협이 되고 있다. 그럼에도 불구하고 대부분의 개발도상국은 재해관리를 간과하여 빈곤의 악순환에서 벗어나지 못하고 있는 실정이다. 본 연구는 2005년 효고행동강령(Hyogo Framework for Action: HFA)의 기본원칙, 2011년 중간평가 검토, 2015년 이후 제시될 새로운 재해위험경감 정책의 틀 속에서 재해위험경감 교육 프로그램을 연구하고자 한다. 이를 위하여 개발도상국 공무원을 대상으로 공적개발원조 프로그램을 운영한 천안의 중앙민방위방재교육원과 일본 고베시의 JICA 등을 방문하여 물 관련 재해 대응의 실질적 개선방향을 모색하였다. 물 관련 재해대응을 위한 교육 프로그램 대상은 실무자와 정책결정자로 설정하고 예방/대비/대응/복구의 유형에 따른 교육과정을 검토한다. 재해 대응 역량강화를 위하여 댐이나 제방 등 홍수위험관리기술과 같은 구조적 방식뿐만 아니라 근본적인 재해위험경감을 위한 홍수위험도 분석과 관리, 도시홍수위험경감계획, 관련 법규제정, 지역홍수위험경감과 민관협력 등과 같은 비구조적 방식에 대한 교육도 포함한다. 이런 측면에서 한국의 경제발전 경험과 물 관련 재해관리 경험을 정책, 사업, 사례와 연관시켜 교육을 진행하고 장단점 비교를 통하여 개발도상국 현지에 적합한 모델을 모색한다. 또한 재해발생시 피해규모를 최소화하게 하는 초동대응을 위해서 행정뿐만 아니라 지역, 시민, 기업 등 다양한 이해 당사자와 주체가 참여하는 종합대책교육을 포함한다. 사회경제발전의 지속을 위해서는 재해에 대한 관리가 매우 중요하다. 특히 인간의 삶에 너무도 익숙하지만 홍수, 가뭄 등으로 치명적인 피해를 야기하는 물 관련 재해에 대응하기 위해서는 물 관리와 관련 재해에 대한 전반적인 이해가 필수적이다. 따라서 한국의 물 관리 경험에 기초한 재해위험경감 교육과 훈련은 개발도상국의 효과적인 재해관리를 가능하게 할 것이다.

• Proceedings of the Korea Water Resources Association Conference
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• 2017.05a
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• pp.257-257
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• 2017

본 연구는 기상이변의 영향으로 지속적으로 발생되고 있는 댐 저수지 붕괴에 대한 원인 분석과 기존의 관련 연구 및 지침 등을 비교 분석하여 현재 실무에서 적용되고 있는 댐 저수지 비상대처계획(EAP) 수립 대상 기준에서 제외되는 시설물의 붕괴 가능성 평가를 통해 EAP 수립 대상의 적정 범위를 제시하고자 하였다. 이를 위해 본 연구에서는 시설물의 붕괴 가능성에 대한 정량적 판단 기준을 각 요인별로 제시하고, EAP 수립 대상에서 제외되는 댐 저수지를 대상으로 붕괴 가능요인을 적용하여 3개 이하의 붕괴요인에 해당될 경우 저위험군, 4개 및 5개의 붕괴요인에 해당될 경우 중위험군과 고위험군으로 각각 분류하여 시설물 붕괴 위험성 정도에 따른 적절한 대응이 이루어질 수 있도록 제안하였다. 댐 저수지 붕괴 사례 분석을 통해 도출된 붕괴 가능성의 주요 요인으로는 저수용량, 제체 높이, 준공 경과연수, 우심피해 및 지진피해 잠재지역이 포함되며, 각 요인별 객관적인 판단기준은 댐 저수용량의 경우 EAP 법적 수립기준 및 과거 붕괴사례 등의 분석을 토대로 붕괴사례 61개소 중에서 약 88%를 차지하는 저수용량 10만톤을 선정하였으며, 댐 높이의 경우 댐의 파괴양상(이종태, 1987)에서 제시한 댐 붕괴부 특성과 미국주댐안전협회(ASDSO: American Society of Dam Safety Official) 학술지인 Dam Safety(2006) 등에서 제안한 기준을 기존의 댐?저수지 붕괴사례에 적용하여 댐 붕괴폭과 댐 높이의 상관관계 분석 결과를 바탕으로 댐 높이 8m 이상을 적정 범위로 고려하였다. 준공 경과연수의 경우에는 국민안전처 "재해위험저수지 댐 관리 지침" 타당성 평가기준인 '시설노후도' 기준과 한국시설안전공단 사회간접자본 노후화 기준에 해당하는 경과연수 기준을 토대로 30년 이상을 기준으로 선정하였으며, 우심피해 및 지진피해 잠재지역은 국민안전처 재해연보(2014)를 기준으로 과거 10년 동안의 우심피해 발생 지역과 기상청 국내 지진 규모 10위권 내에 포함되는 지역을 고려 대상으로 하였다. 본 연구에서 도출한 시설물 붕괴 가능성에 대한 판단기준을 국민안전처에서 고시한 EAP 수립 대상에서 제외되는 지자체 재해위험저수지 354개소에 적용해 본 결과, 저위험군 16개소, 중위험군 5개소, 고위험군 2개소로 각각 조사되었다. 저위험군은 전문 시설물 관리자에 의한 주기적인 시설물 점검 및 관찰이 필요할 것으로 사료되며, 중 고위험군에 속하는 시설물의 경우 본 연구의 결과를 바탕으로 시설물 하류지역의 실질적인 인명 및 경제적 피해 가능성에 대한 보다 면밀한 조사를 통해 EAP 수립 대상 포함여부를 결정하여야 할 것으로 판단된다.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.36 no.4
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• pp.425-430
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• 2012

In this study, a preconverter of an MCFC for an emergency electric power supplier is numerically simulated to increase the hydrogen production from natural gas (methane). A commercial code is used to simulate a porous catalyst with a user subroutine to model three dominant chemical reactions-steam reforming, water-gas shift, and direct steam reforming. To achieve a fuel conversion rate of 10% in the preconverter, the required external heat flux is supplied from the outer wall of the preconverter. The calculated results show that the temperature distribution and chemical reaction are extremely nonuniform near the wall of the preconverter. These phenomena can be explained by the low heat conductivity of the porous catalyst and the endothermic reforming reaction. The calculated results indicate that the use of a compact-size preconverter makes the chemical reaction more uniform and provides many advantages for catalyst maintenance.