• 한국산학기술학회논문지
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• 제16권10호
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• pp.6949-6958
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• 2015

무선통신기반 열차제어시스템은 관할영역 내에 운행 중인 열차의 위치정보를 지상시스템에서 실시간으로 수신하고 다시 각각의 열차의 차상시스템에 새로운 이동권한을 제공함으로써 안전한 간격제어를 수행한다. 열차제어시스템의 성능은 최소 운전시격으로 평가되며 그것은 열차제어시스템의 간격제어 성능뿐만 아니라 운영특성 그리고 열차의 특성을 반영하여 계산된다. 본 논문은 무선통신기반 열차제어시스템의 운전시격 계산과 운전시격을 개선하기 위한 새로운 열차간격제어 알고리즘을 제안한다. 제안된 운전시격 계산 방법은 열차제어시스템 간격제어 성능을 반영한 안전마진 추정을 통해 각각 역간 운전시격과 역 운전시격을 정의한다. 또한 제안된 열차간격제어 개선 알고리즘은 간격제어 개선을 위해 거리와 속도를 포함하는 이동권한을 새롭게 정의하며 선행열차에서 필연적으로 발생하는 제동거리를 이용함으로써 열차의 운전시격을 향상시킬 수 있다. 제안된 운전시격 계산방법을 한국형 무선통신기반 열차제어시스템의 간격제어 성능을 대상으로 시뮬레이션을 수행하며 개선된 열차간격제어 알고리즘과 비교분석 한다. 시뮬레이션 결과에 따르면 제안된 운전시격 계산방법은 향후 무선통신기반 열차제어시스템의 성능 지표로 활용이 가능하며 제안된 간격제어 알고리즘은 기존의 무선통신기반 열차제어시스템의 역 운전시격과 역간 운전시격을 개선할 수 있음을 확인한다.

• 한국산학기술학회논문지
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• 제18권12호
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• pp.434-442
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• 2017

본 연구는 부산지역 교정환자를 대상으로 부정교합의 종류와 교정치료에 대한 인식이 삶의 질에 미치는 영향을 파악하고, 부정교합의 종류에 따른 맞춤형 교육프로그램을 개발하여 삶의 질 향상의 기초자료로 삼고자 한다. 2015년 12월부터 약 6개월간 설문조사하여 최종 472부를 분석하였다. 연구결과는 부정교합의 가족력은 I급은 없음, II급, III급은 있음으로 응답하였고, 교육 실천은 자주실천에서 부정교합의 종류에 따른 차이를 보였다(p=0.003). 교정치료의 만족감에서는 불편감은 I급은 기간, II급과 III급은 통증(p=0.035)이였고, 통증부위에서는 치아가 가장 많았으나 II급에서 가장 높아 차이를 보였다(p<0.001). 교정치료 만족도에 따른 삶의 질에서는 현재 만족도가 높을수록, 자신감이 보통인 경우 삶의 질이 높았으며, 교정치료 시작 계기에서는 발음문제(p=0.013), 저작 불편감(p<0.001), 턱관절 소리(p<0.001)가 있는 경우 삶의 질이 낮았다. 구강건강관련 삶의 질에 미치는 요인으로는 교정치료시기(p<0.001), 현재 만족감(p<0.001), 자신감 변화(p=0.003), 주관적 치아상태(p=0.008), 교합의 종류(p=0.019)순으로 영향을 미쳤다. 따라서 교정치료를 받는 환자들의 구강건강 상태를 면밀하게 분석하고 맞춤형 교정상담프로그램을 통하여 교정기간에도 삶의 질을 향상시킬 수 있어야 한다.

• 대한환경공학회지
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• 제36권11호
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• pp.753-757
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• 2014

산화전극부 전극은 단순히 전자를 받아 전달할 수 있는 역할 뿐만 아니라 공극이 많아 표면적이 큰 구조로 미생물을 고정화할 수 있는 표면적을 제공할 수 있어야 한다. 미생물의 수가 많을수록 폐수처리 효율과 전류발생을 높일 수 있기 때문이다. 따라서 전극은 미생물연료전지의 효율을 높일 수 있는 중요한 역할을 하는 인자 중의 하나이다. 본 연구는 미생물연료전지에 사용하는 고가의 흑연펠트를 스텐철사 타래(철 수세미)로 대체할 수 있는지 알아보기 위한 것이다. 이 연구에 사용된 가축분뇨는 전처리를 거친 후 유기오염물질(COD)로 500 mg/L로 희석한 것을 이용하였고, 이때 전류 발생은 스텐철사 타래를 적용하였을 때 약 5% 정도 낮았지만 큰 차이가 없는 것으로 나타났다. 유기오염물질(COD)의 감소는 스텐철사 타래를 이용하였을 때 88.3%이었으며, 흑연펠트를 사용하였을 때 82.4%로 스텐철사 타래의 제거율이 더 높게 나타났다. 암모니아성 질소 이온의 경우는 두 경우 모두 반응시간에 따라 농도 변화가 거의 없는 것으로 나타났다. 이 결과 스텐철사 타래를 적용하였을 때 전류발생이나 수처리 측면 모두 효과가 유사하거나 더 좋은 결과를 보였으며, 초기 시스템을 구축하는 비용을 약 1/50 정도로 줄일 수 있는 것으로 예상되어. 흑연펠트 대체제로 적용이 가능할 것으로 판단된다.

• 한국치위생학회지
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• 제9권3호
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• pp.282-293
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• 2009

The purpose of this study was to examine the degree of infection control implemented at dental offices and factors affecting it in an attempt to help promote the health of dental health care workers. The subjects in this study were 180 medical personnels who worked at dental offices in the region of South Jeolla Province. A self-administered survey was conducted from April 1 to May 30, 2008, and the collected data were analyzed. The findings of the study were as follows: 1. As for the implementation of infection control at the dental offices, what the health care workers investigated did the most was post-treatment hand washing(95.0), a constant separation of infectious wastes(94.4), wearing rubber gloves all the time during medical instrument cleansing(92.8) and pre-treatment hand washing(91.7). 2. In regard to the implementation of infection control at the dental offices, what the dental personnels did the least was drying their hands with air(5.0), wearing goggles in times of treatment(23.3), receiving regular education on infection control(26.7) and putting sterilizers to a performance test on a regular basis(43.9). 3. The dental health care workers were significantly different according to age in the management of contagious diseases(p=0.005). Their career made a significant difference to the management of contagious diseases(p=0.000) and instrument cleansing/sterilization(p=0.043). The service area made a significant difference to wearing and managing personal protective clothes (p=0.040) and waste management(p=0.040). 4. Concerning the relationship between the acquisition of dental hygienist certificate and the practice of infection control, whether the dental health care workers were certified or not made no significant difference to that. 5. As to the correlation among the factors affecting the prevention and management of contagious diseases, there was a positive correlation among hand washing(r=0.379), wearing and managing personal protective clothes(r=0.349), instrument cleansing/sterilization(r=0.323) and waste management(r=0.388). All the factors made a statistically significant difference to the prevention and management of contagious diseases(p<0.01).

• 한국식품영양학회지
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• 제20권2호
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• pp.226-239
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• 2007

The purpose of this study was to identify the problems related to the purchasing processes of school foodservices that should be corrected for the food service safety, by examining the purchasing processes and the status of supplier selection. A questionnaire was given to 300 dietitians working at self-operated food services. Ninety-eight responses, excluding incomplete answers, were used for the statistical analysis. The survey consisted of three parts: the general characteristics of the school foodservice and dietitian, purchasing processes and supplier selection, and the purchase specifications. We found that 84% of the contract was made by informal purchasing, and the contract period was 6 months or one year. For supplier selection, problems related to the document screening systems were the superficiality of the content(45.7%) and the absence or lack of clarity of the appraisal criteria(34.8%). The important factors for the facility and equipment standards of suppliers were included unclear evaluation methods for content(41.1%) and inappropriate appraisal lists(21.1%), while unclear evaluation methods for content(41.9%) and absence or lack of clarity of the appraisal criteria(20.4%) were the problems pertaining to the supplier evaluation checklist. When using the Food Labeling Standards to select suppliers, confirmation of the sell-by date and the storage method had the highest score at 3.85 out of 5. For supplier selection, only 25% of the contract was made by using the purchase specifications. The levels of satisfaction of with Kimchi and rice cakes suppliers were significantly different according to employment type and educational background, respectively. Depending on working experiences, satisfaction was significantly different for the use of document screening, as a standard for the selection and management of suppliers, and for the facility and equipment standards of suppliers, The use of purchase specifications was different by employment type, while the use of purchase specifications for contracts was different by working experience. These results imply that the specialization of suppliers is necessary to unsure food safety. Therefore, the objective methods to evaluate the suppliers should be developed by the government, and appropriate education programs for dietitians should be prepared to enhance the utilization of purchase specifications.

• 한국식생활문화학회지
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• 제20권5호
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• pp.594-602
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• 2005

The purpose of this study was to investigate eating behaviors related to snack and self-purchasing snack (SPS) among elementary school children. Self-administered questionnairs were completed by 352, 5th and 6th grade elementary school students living in 3 different regions which included apartment region in Bundangn, Sungnam (apartment group, n=116), residences in Seodaemun-Gu and Mapo-Gu, Seoul (kang-buk group, n=103) and residence in industrial region in Sungnam (industry group, n=133). The results were as follows: A significantly higher proportion (64.7%) of the apartment group had breakfast every morning than those of kang-buk (48.6%) or industry (52.1%) group (p<0.01). As for the frequency rate of snack and self-purchasing snack (SPS), 53.9% of the subjects answered taking snack more than once per day, 22.8%, once for few days and 23.3%, almost not. However, 15.5% of the subject had SPS once or more per day, 30.7%, 1-2 times per week and 22.4%, almost not. Those of apartment group showed significantly lower SPS frequencies (p<0.01), since higher proportions answered having SPS 1-2times per week (40.9%) and almost not (31.3%) compared to other groups. The reasons for having SPS turned out to be 'hunger' 54.7%, 'being habitual', 15.9%, 'bing bored', 15.7% and 'with peers' 13.7%. When subjects selected SPS foods, they considered taste (31.5%), price (23.0%), mood at the time (14.1%), sanitorial aspect (10.2%) and quantity (10.1%) rather than nutritional aspect (7.2%). Subjects' pocket money was estimated as 3736 won per week and SPS expense per time as 706 won. But subjects who spent more than 2000 won for SPS expense were significantly higher (33.0%) in apartment group than those of other groups (p<0.01). The favorite snack items that subjects having at home were fruit, ice cream, milk and yoghurt, cookies, ramen and bread in order. And favorite SPS items turned out to be ice cream, cookies, duckbokki, frozen bars, gum, chocholate and candy in order. The frequency rate of SPS were evaluated to be significantly related by several variables: those living in apartment area (p<0.01), those taking breakfast regularly (p<0.01), those of normal weight status by Rohrer index (p<0.05) and those receiving less pocket money (p<0.01) showed lower SPS frequency rate.

• 한국농림기상학회지
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• 제21권4호
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• pp.358-365
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• 2019

영농형 태양광 발전은 기존 농지에 태양광 패널을 설치하여 농지 보존과 일정 수확량 유지를 전제로 전기 생산도 병행하는 시스템이다. 최근 태양광 부지 수요 충족 및 농촌 경쟁력 제고를 위한 방안으로 주목 받고 있다. 따라서, 본격적인 개발에 앞서 영농형 태양광 패널 하부에서의 경작지 차광 정도를 분석하는 것이 작물 생육·수확량 변동 예측에 반드시 필요할 것이다. 본 실험은 연구용 영농형 태양광 건설에 앞서, 영농형 태양광 시설 규격과 유사한 모의 차광 시설을 설치하고 하부의 광합성유효복사량 특성을 분석하였다. 차광막 하부와 외부의 광합성유효복사량 차이는 일사광에서 산란광 비율이 낮아질수록 증가하였는데, 최대 17.08 mol/㎡/day (맑은 날), 최소 3.03 mol/㎡/day (흐린 날)이었다. 이러한 광 조건 변화는 벼의 초기 생육에 있어 초장의 증가와 주당경수의 감소를 가져왔다.

• 가정과삶의질연구
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• 제26권3호
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• pp.37-52
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• 2008

The purpose of this study was to provide the valid data about residential-linked pension insurance development. The development was a part of national housing projects, which was an incentive for rural living of retired people, in order to relieve residential issues of elderly and revitalize rural communities by residents moving from cities. The insuring intent, decisive insuring factors and the residential service demand degree of people preparing retirement were analyzed. Data was collected in October, 2007. 364 Sample Subjects lived in Seoul Metropolitan area. Firstly, more than 90% of respondents had intention to purchase a residential-linked pension insurance and about 50% of them necessarily desired receiving premium for moving in. This indicated that it could be developed as an insurance which helped to meet housing expenses by housing-linked system, and in the mean time, it met the original purpose of pension insurance as the pension benefit could be guaranteed for all the insurance subscribers. Secondly, the respondents, whose income and private assets were higher, were able to pay more for insurance compared to average. Therefore, It was necessary to regulate monthly insurance bill and the payment period according to asset states of insurance subscribers after establishing certain amount of total insurance payment. Thirdly, by and large, it indicated the tendency that the less they prepare for older age the later they wanted to move into the pension insurance residence. It was inferred that in the case of insufficient preparation for older age, people preferred preparing behind time by postponing move in to moving in early to enjoy retired life, due to uncertainties. lastly, the respondents understood the significance of health, medical treatment and emergency management service and these two services were preferred as essential provided services. Because of the necessity of developing residential-linked pension insurance was found to be positive, further research to find the real cost, directives for operation and institutional support for this type of pension insurance might be needed.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제27권5호
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• pp.447-452
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• 2001

Hyperbaric oxygen therapy(HBO) is defined as breathing 100% oxygen while in an enclosed system pressurized to greater than on atmosphere(sea level). This increased oxygen delivery furthers your body's ability to kill germs and to increase healing. HBO is a supplemental therapy to be used in addition to the current medical and surgical therapy you are receiving. HBO typically is used to complement treatments of medical problems such as bone infections, complication of radiotherapy, and certain chronic, non-healing wounds. On an emergency basis, the chamber also is used to treat problems such as carbon monoxide poisoning and the decompression sickness. We analysed stastically cases which are treated by hyperbaric oxygen therapy in point of oral and maxillofacial region on the Kangnam General Hospital for aid in comprehension and application of this therapy. Total 760 patients were treated at Gangnam General Hospital from July 1996 to September 1999. They were classified by region to Decompression sickness(DCS), Carbon monoxide poisoning(CO), General surgery(GS), Orthopedics(OS), Oral and Maxillofacial surgery(OMFS), others. Patients of Oral and Maxillofacial surgery were divided by diseses to Osteomyelitis, Osteoradionecrosis, Reconstruction, Bone graft, Difficult wounds, others. The results were as follows. 1. This institute conducts HBO therapy for DCS which takes up 62% and 10.5% for OMF region. 2. In OMF region, Osteomyelitis is 40%, Osteoradionecrosis is next, Bone graft, and Reconstruction is a row. 3. According to our precious study, HBO has been frequently conducted in OMF region compared to past, however, it is less actively conducted in this area for research than other conturies. Therefore, We need further application to the clinical use.

• 한국환경과학회지
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• 제13권12호
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• pp.1089-1102
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• 2004

Seasonal variation of biogeochemical characteristics was determined in Lake Shihwa from October 2002 to August 2003. When the lake was artificially constructed for the freshwater reservoir in 1988, the development of the strong haline density stratification resulted in two-layered system in water column and hypoxic/anoxic environment prevailed in the bottom layer due to oxidation of accumulated organic matters in the lake. Recently, seawater flux to the lake through the sluice has been increased to improve water quality in the lake since 2000, but seasonal stratification and hypoxic bottom layer of the lake still developed in the summer due to the nature of artificially enclosed lake system. As the lake is still receiving tremendous amount of organic matters and other pollutants from neighboring streams during the rainy summer season, limited seawater flux sluicing into the lake may not be enough for the physical and biogeochemical mass balance especially in the summer. The excess of accumulated organic matters in the bottom layer apparently exhausted dissolved oxygen and affected biogeochemical distributions and processes of organic and inorganic compounds in the stratified two-layered environment in the summer. During the summer, ammonia and dissolved organic carbon remarkably increased in the bottom layer due to the hypoxic/anoxic condition in the bottom layer. Phosphate also increased as the result of benthic flux from the bottom sediment. Meanwhile, dissolved organic carbon showed the highest value at the upstream area and decreased along the salinity gradient in the lake. In addition to the sources from the upstream, autochthonous origin of particulate organic carbon from algal bloom in the lake might be more important for sustaining aggravated water quality and development of deteriorated bottom environment in the summer. The removal of trace metals could be attributed to scavenging by strong insoluble metal-sulfide compounds in the hypoxic/anoxic bottom layer in the summer.