• 한국표면공학회지
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• 제56권2호
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• pp.125-136
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• 2023

Recently, ammonia has emerged as an alternative energy source that can reduce carbon emissions in various industries. Ammonia is used as a fuel in internal combustion engines because it contains no carbon in its components and does not emit any carbon when burned. It is also used in various fields such as fertilizer production, refrigeration, cleaning and disinfection, and drug manufacturing due to its unique characteristics, such as high volatility and easy solubility in water. However, it is highly corrosive to metals and is a toxic gas that can pose a risk to human health, so caution must be exercised when using it. In particular, stress corrosion cracking may occur in containers or manufacturing facilities made of carbon-manganese steel or nickel steel, so special care is needed. As ammonia has emerged as an alternative fuel for reducing carbon emissions, there is a need for a rapid response. Therefore, based on a deep understanding of the causes and mechanisms of ammonia corrosion, it is important to develop new corrosion inhibitors, improve corrosion monitoring and prediction systems, and study corrosion prevention design.

• 한국식품조리과학회지
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• 제19권4호
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• pp.477-492
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• 2003

The purposes of the study were to establish HACCP-based standards and guidelines for conducting a plan review to build, or renovate, hospital food service establishments, and ensure the safety of foodservice and reduce the risk of food borne illness. The scope of the study included suggestion for the planning of hospital foodservice facilities: layout, design, equipment and modeling. The results of this study can be summarized as follows: 1) The development of a foodservice facility plan based on the results of a survey, literature reviews and the results of interviews with foodservice managers from 9 general hospitals. This was composed of operational policies in foodservices, layout characteristics, space allocation, selection, design, specification standards for equipment and the construction principles of foodservice facilities. 2) Two foodservice facility models were developed, one for general hospitals with 900 beds (2,000 patients and 2,500 employee meals per day) and the other for general hospitals with 300 beds (600 patients and 650 employees meals per day). 3) The suggested kitchen space requirements for the foodservice facility models were 341.2 ㎡ (W 17,100mm x L 23,700mm) and 998.8㎡ (W 35,600mm x L 32,800mm) for the 300 and 900 beds hospitals, respectively, with both designs being rectangular. The space requirements for the equipment, in relation to the total operational area, in terms of ratios were 1:3.5 and 1:3.8 for the 300 and 900 beds hospitals, respectively. The recommended space allowances per bed for the developed foodservice facility models were 1.15 ㎡ and 1.11 ㎡ for the 300 and 900 beds hospitals, respectively, which were increased by more than 30% compared to those suggested in the precedent study, and considered appropriate for the implementation of the HACCP system. 4) The hospital foodservice facilities plans and models were developed based on the general sanitation standards, guidelines and the HACCP system, and included foodservice facility layout, product flow, physical separation between contaminated and sanitary areas, foodservice facility specifications with a 1/300 scale for a 300 bed, and a 1/400 scale for a 900 beds blueprint. 5) The main features of the developed foodservice facility plans and models were; physical separation between contaminated and sanitary areas to prevent cross contamination, product flow in one direction from the arrival of the raw material to the finished product, and separation of different work areas and the process of receiving & preparation of products, refrigeration & storage, cooking, assembly, cleaning & disinfection, employee areas and janitorial facilities. The proposed models from this study were presented as examples for those wanting to build, or renovate, their facility for the production of foods.

• 조명전기설비학회논문지
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• 제12권3호
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• pp.104-113
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• 1998

일반적으로 수처리시설은 상수처리장, 하수처리장 등을 포함하며, 이중에서 상수처리공정은 취수, 응집, 침전, 여파, 살균소독처리 과정으로 구성되어 있다. 그리고, 응집.침선 처리공정은 상수처리시스템에서 가장 핵심부분 으로, 탁도의 처리에 가장 크게 영향을 주게 되며, 이에 따른 응집제의 주입공정을 개선하기 위한 노력이 필요하다. 응집제 주입공정은 응집 반응과정에 관여하는 여러 외부요소들과 탁도와의 관계가 명확히 규정되어 있지 않고, 외부환경조건에 따라 다양하게 변하는 원수로부터 적절한 응집제의 양을 간단하게 결정할 수 없는 상황이다. 따라서, 전반적인 원수처리 공정의 자동화를 위해서는 응집제 주입공정 자동화와 수처과시설의 유지관리기 능을 갖춘 운용지원시스템을 관리자에게 제공하는 것이 요구되었다. 본 논문에서는 수처리시설의 설비유지관리와 응집제 주입공정을 자동화하는 운용지원시스템의 프로토타입올 구현하고자 한다. 응집제 주업공정의 자동화를 위해서 실제 수처리공정에서 1년간 수행된 웅집제 투입양과 원수 의 수질을 결정하는 여러 요소들과의 데이터를 이용하여 신경회로망을 학습시카고, 이를 이용하여 응집제 주업량을 결정하도록 하였다. 이렇게 구축된 웅집제 주입공정 자동화는 운영지원 시스템내 에서 운영되며, 운영지원 시스템은 상수처리설비의 유지분수뜰 위한 설비관리와 상태감시를 하는 환경을 구축하였다.

• 한국환경농학회지
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• 제27권4호
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• pp.435-440
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• 2008

E. coli, S. agalactiae, S. aureus는 젖소의 유방염을 유발하는 주요 원인균들이다. 이 균들은 분변 혹은 우유에 존재하며, 감염되지 않은 다른 개체로의 감염을 유발한다. 자외선은 소독제로서 이미 산업계 및 의료계에서 쓰레기 및 물의 살균에 사용되고 있으므로, 자외선을 이용하여 젖소의 유방염 확산을 방지하는 것의 실효성을 검증하였다. 분변의 함수율은 젖소 유방염 유발균의 증식에 영향을 미치지 않았고, 144시간 이상의 장시간 생존이 가능함을 확인하였다. 자외선의 조사 시, 조사하는 동안 우분뇨 및 톱밥을 교반하는 것이 교반하지 않는 것보다 균의 증식을 억압하는 것을 확인할 수 있었다. 한편, 자외선의 살균력은 함수율이 낮을수록, 조사시간이 길수록, 조사거리가 짧을수록 더 증가하는 것을 확인할 수 있었다. 본 실험을 통해 얻은 함수율, 조사시간, 조사거리, 교반 여부에 대한 결과는 환경 유래, 특히 우분뇨 유래 젖소 유방염의 감염을 예방하고자 할 때 자외선 살균기의 적용이 가능할 것이며, 현장에 적용할 살균기의 제작에 중요한 기초 자료로서 활용될 것이다.

• 한국산학기술학회논문지
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• 제15권7호
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• pp.4310-4317
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• 2014

본 연구는 수작업 떡류의 HACCP(Hazard Analysis Critical Control Point)시스템 적용을 위한 목적으로 하였다. 본 실험에 사용된 시료는 떡의 주원료, 작업장 시설, 도구와 작업자는, 2012년 9월 12일~2013년 2월 13일까지 서울시 용산구 서계동 소재에 있는 KB 업체에서 제공받았다. 제조공정도는 일반적인 떡류 제조업체의 제조공정을 참고로 작성하였다. 제조 공정도는 원료 농산물(맵쌀, 찹쌀, 잣 등), 부재료(분말원료), 용수와 포장재료의 입고, 보관, 정선 및 계량, 세척, 불림, 탈수, 분쇄, 주재료 혼합, 익반죽, 수작업 성형, 증자, 냉각, 절단, 내포장, 금속검출, 외포장, 보관 및 출하공정으로 작성하였다. 원료 농산물의 미생물학적 위해요소 분석결과는 Table 1과 같다. 본 연구결과 증자공정 후의 떡과 원재료의 미생물검사 결과는 안전한 것으로 보인다. 하지만, 체계적인 세척 및 소독을 실시하여 미생물학적 위해를 감소시키고 작업자 위생교육 등을 통하여 개인위생개념 향상과 작업장의 미생물 관리가 함께 이루어져야 할 것으로 여겨진다.

• 한국환경보건학회지
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• 제46권5호
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• pp.599-609
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• 2020

Objectives: Coronavirus disease 2019 (COVID-19) first emerged in December 2019 in Wuhan, China, and has rapidly become a global pandemic with over 26.4 million confirmed cases and approximately 871,000 fatalities worldwide as of this writing. In the Republic of Korea, disease clusters frequently occurred in long-term care hospitals where the majority of residents are elderly with underlying medical conditions. Despite the fact that public health authorities and local community health centers have put tremendous efforts into preventing the spread of disease, positive cases have continued to occur. Thus, the Korea Centers for Disease Control & Prevention rapid response team decided to conduct an environmental investigation of a long-term care hospital to identify whether environmental contamination has remained and contributed to the spread of COVID-19. Methods: An environmental investigation was conducted at Hospital A. The characteristics of the facility and its HVAC system were assessed by checking the layout and interviewing the people in charge. A total of 64 surface samples were collected from areas of concern, including patient rooms, toilets, elevators, and nurses' station. These samples were tested by a regional health and environmental research institute using real-time reverse transcription polymerase chain reaction. Results: All samples from Hospital A were confirmed to be negative. Through interviews with high-level personnel at the regional community health center, we found that extensive disinfection is frequently performed on potentially contaminated areas in Hospital A in accordance with government guidelines. Conclusion: The environmental control measures implemented in Hospital A had been sufficient for mitigating the risk of further infection, suggesting that such measures may also be effective for other long-term health care facilities.

• Journal of Preventive Medicine and Public Health
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• 제46권2호
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• pp.62-73
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• 2013

Objectives: An outbreak of hepatitis A occurred at a residential facility for the disabled in July 10, 2011. This investigation was carried out to develop a response plan, and to find the infection source of the disease. Methods: A field epidemiologist investigated the symptoms, vaccination histories, living environments, and probable infection sources with 51 residents and 31 teachers and staff members. In July 25, 81 subjects were tested for the hepatitis A virus antibody, and specimens of the initial 3 cases and the last case were genetically tested. Results: Three cases occurred July 10 to 14, twelve cases August 3 to 9, and the last case on August 29. Among the teachers and staff, no one was IgM positive (on July 25). The base sequences of the initial 3 and of the last case were identical. The vehicle of the outbreak was believed to be a single person. The initial 3 patients were exposed at the same time and they might have disseminated the infection among the patients who developed symptoms in early August, and the last patient might have, in turn, been infected by the early August cases. Conclusions: The initial source of infection is not clear, but volunteers could freely come into contact with residents, and an infected volunteer might have been the common infection source of the initial patients. Volunteers' washing their hands only after their activity might be the cause of this outbreak. Although there may be other possible causes, it would be reasonable to ask volunteers to wash their hands both before and after their activities.

• 한국가금학회지
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• 제37권3호
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• pp.289-295
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• 2010

축산물은 사람의 주요 식품원으로서 중요하지만, 식중독균의 주요 매개체이기도 하다. FAO/WHO(2002) 보고에 따르면 유럽에서 발생하는 식중독의 약 26%가 닭고기 및 계란을 포함한 가금유래로서, 식중독 발생의 77.1%가 살모넬라 균이 원인으로 나타났으며, 특히, S. enteritidis가 1/3 이상을 차지하는 것으로 나타났다. 전세계적으로 살모넬라 오염 가금 생산물의 공중보건학적 위험을 해결하기 위한 제어 방안과 프로그램에 대한 관심이 확산되고 있으며, EU와 미국을 중심으로 살모넬라 제어를 위해 사육단계에서부터 도축 및 가공단계까지 전 과정에서의 살모넬라 제어 프로그램을 적용 확대해가고 있다. 식품 안전에 대한 요구가 증가되고 있는 현 시점에서 제시한 바와 같은 살모넬라 차단 방역 시스템 설계, 현장에 쉽게 적용할 수 있는 수준의 가이드라인 개발 및 백신과 유기산, 경쟁적 배제제, 프로바이오틱스, 박테리오파아지 등과 같은 살모넬라 저해제의 적용을 포함한 살모넬라 부재 가금 및 안전 계육 생산기법의 개발이 필요하다.

• 한국환경보건학회지
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• 제44권5호
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• pp.452-459
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• 2018

Objectives: We aimed to examine whether dental waste was being managed adequately at different types of dental institutions in City D in South Korea. Methods: The staff responsible for disinfection at 101 dental offices and clinics (six dentistry departments of general hospitals, 12 dental hospitals, and 83 dental clinics) was interviewed. Results: Solid suction pump waste was handled appropriately at four of the general hospital dentistry departments (66.7%), six dental hospitals (50.0%), and 15 dental clinics (18.1%). Solid spittoon waste was handled appropriately at four general hospital dentistry departments (66.7%), seven dental hospitals (58.3%), and 14 dental clinics (16.9%). Developer and fixer were handled appropriately by a subcontractor at two general hospital dentistry departments (100.0%), five dental hospitals (100.0%), and 24 dental clinics (75.0%). Impression materials were handled appropriately at four general hospital dentistry departments (66.7%), six dental hospitals (50.0%), and 11 dental clinics (13.3%). The plastic covers of intra-oral radiography films were handled appropriately at five general hospital dentistry departments (100.0%), eight dental hospitals (72.7%), and 22 dental clinics (30.1%). Conclusion: South Korea must implement detailed and specialized guidelines for the disposal of solid and general medical waste from dental institutions. Moreover, waste disposal training should be provided annually, and not only once every three years.

• 환경위생공학
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• 제14권2호
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• pp.56-67
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• 1999

This study was performed to suggest the basic data and plans for the establishment of safe water supply plans in simple water supply piped system in the rural areas. In 4 different places, 24 points of water sources 36 points of taps from water sources were sampled. Of the whole 60 points, 55 points were ground water and 5 points were surface water. 14 items were measured for the analysis of water quality on each samples. The measured items were analyzed again by statistical method ; cluster analysis and principle components analysis. The results of this study are as followed. 1) In water quality analysis on water sources, 4 items, bacteria, E.coli, NH3-N and Fe exceed the standard. Of 24 points, 20 points(83%) on bacteria, 1 point(4%) on NH3-N and Fe exceed the standard. 2) In water quality analysis on near and remote taps, 4 items, bacteria, E.coli, NH3-N and Fe , exceed the standard. Of 36 points, 20 points (81%) on bactria, 1 pint(3%) on NH3-N and Fe exceed the standard. 3)Cluster analysis on water quality shows the differences by the kinds of water sources, geographical characteristics and distance from water sources. 4) Principle components analysis on ground water shows that Factor 1 and Factor 3 are natural fluctuation by the content of soil. Also, Factor 2 and Factor 4 are penetration of pollutants to underground. Therefore, it is needed to take deeper ground water in order to prevent from pollution in the areas which have ground water as water source . 5) Principle components analysis on surface water shows that Factor 1 is penetration of vacteria from surface to water source when rainfalls. Also, Factor 2 is fluctuation of water quality by the geographical characteristics. Therefore, the counterplans against non-point pollution source must be taken. Filtration and disinfection facilities are needed in the areas which have surface water as water source.