• 한국미생물·생명공학회지
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• 제50권2호
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• pp.165-192
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• 2022

본 논문에서는 실외 대기 환경의 바이오에어로졸 혹은 입자상물질의 미생물 메타게놈 특성과 이에 영향을 미치는 기후 및 환경 인자의 영향을 고찰하였다. 시료 채취 지역 및 환경 조건 특성별 대기 중 세균과 곰팡이 농도를 요약 하고, 에어로졸과 PM 시료의 세균과 곰팡이의 메타게놈 특성을 조사하기 위한 비배양법 기반 분석방법과 메타게놈 특성을 정리하였다. 또한, 세균과 곰팡이의 메타게놈 특성과 다양성 및 특성에 미치는 기상 인자와 환경 인자의 영향을 고찰하였다. 대기 중 미생물의 생존, 생장과 분산은 지역 기상 조건 및 대기 오염 물질에 의해 크게 영향을 받았다. 일반적으로 기온이 상승함에 따라 AM 농도는 증가하지만, 여름에는 고온과 강한 자외선의 영향으로 AM 농도가 감소하였다. 습도와 미생물 농도는 양의 상관성을 보이나, 습도가 너무 높으면 AM의 분산이 지연되었다. 이러한 종합적인 고찰 결과는 대기권에서 미생물의 역할과 기능을 이해하고, 이들 미생물에 의해 야기되는 환경 및 공중보건 문제를 해결하기 위한 전략 수립 및 저감 기술 개발에 활용될 수 있다.

• 한국운동역학회지
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• 제19권1호
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• pp.159-166
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• 2009

본 연구의 목적은 실외 보행 실험 시 사용하기에 간편한 가속도계를 이용하여 보행 이벤트를 자동으로 검출하는 알고리즘을 개발하고 검증하는 것이다. 개발된 알고리즘은 신발의 발등에 부착된 3축 가속도계의 가속도의 총합과 보행 진행 방향(x축) 가속도를 이용하였다. 가속도 총합은 착지 시점의 검출에, x축 가속도는 이지 시점의 검출에 각각 사용되었다. 7명의 피험자가 느린 보행 속도 선호 보행 속도 빠른 보행 속도로 보행 실험을 수행하였고, 개발된 알고리즘의 검증을 위해 지면반력기를 포함한 3차원동작분석시스템과 동시에 실시되었다. 지면반력기를 이용한 보행 시점을 기준으로, 기존에 발표된 동작 자료만을 이용한 알고리즘을 통하여 얻어진 보행 시점도 함께 비교 하였다. 그 결과, 고안된 알고리즘의 정확도는 지면반력기를 이용한 값에 평균, 착지시점은 $22.33{\pm}17.45ms$, 이지시점은 $26.82{\pm}14.78ms$의 차이가 났고, 그 오차의 패턴이 일관적으로 20ms가량 먼저 검출되는 경향이 있었다. 일반적으로 트레드밀 실험에서 많이 사용되는 동작데이터를 통한 보행 시점의 비교에서도 크게 차이를 보이지 않았다. 그러므로 개발된 알고리즘은 실외 실험의 보행 시점 검출에 이용할 수 있을 것으로 판단된다. 추후 연구로는 현재의 가속도계만으로 보행 시점뿐 만아니라, 중력가속도 성분을 제거하여 보행 공간변인의 추출이 필요할 것이다.

• 한국실내디자인학회논문집
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• 제26권2호
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• pp.72-82
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• 2017

Current world population is rapidly ageing and the disabled population is expected to age seriously as well. The concern about the elderly and the disabled is increased largely not just the field of social welfare and service but the housing planning where the physical environment of everyday life is. Recently in Ireland, 'Universal Design Guideline for Homes' is established and proposed in public. It is considered as initial and special national policy for the socially venerable. The purpose of this research is to analyze the User Benefit Characteristics(UBC) of 'Universal Design Guideline for Homes in Ireland' and clearly organize the characteristics for comprehensive communication. The research subjects are 444 guidelines of 'Universal Design Guideline for Homes in Ireland.' The research is conducted by contents analysis technique, and each guideline is analyzed by the 4 main concepts of UBC- 'Behavioral Facilitation(BF)', 'Physiological Maintenance(PhM)', 'Perceptual Maintenance(PM)', 'Social Facilitation(SF).' As results, the User Benefit Characteristic of 'Universal Design Guideline for Homes in Ireland' is ordered by PhM>PM>BF>SF. The design guidelines are supposed to support ageing in place and sustainable living in the existing houses even though people are ageing or being disabled. 'Universal Design Guideline for Homes in Ireland' supports safe behavior and comfort cognition especially in indoor and surrounding outdoor environment. This research is significant for sharing the knowledge and comprehension of decreasing environmental stress of the elderly in specific, and could be utilized for developing new elderly housing in future.

• Journal of Nutrition and Health
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• 제14권4호
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• pp.209-219
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• 1981

To evaluate long-term metabolic response of free-living Korean subjects consuming local sources adequately or slightly below habitual intake. Subjects, six male medical students aged 23-25 years were free-living, but consumed diets in the metabolic unit. They were healthy as determined from medical laborarory tests. They belong to the Korean middle-class. Temperature of outdoor during study were ranged between -2 to $26^{\circ}C$, whereas the indoor were $18-22^{\circ}C$. Animal protein ranged between 25-30% of total calorie. The three meals and a vitamin supplement to meet recommendation were given daily. Three 50day periods following the design were used to test the protein-energy adequacy of the diet. Urinary nitrogen excretion was measured daily. Fecal samples were pooled for the last 5 days of each week. Nitrogen balance was computed using 5mg N/Kg skin and miscellaneous losses. Body weight was measured daily. The study was covered on 126 metabolic observations weekly. Body weight changes were relatively stable with the energy intake of 37-44Kca1/kg, and N-balances were also relatively stable, but it was influenced by physical and or mental stress somehow. It could be assumed that the mean protein and energy requirement were $190{\pm}10mg$ N/Kg with $41{\pm}2$ Kcal/kg, and the mean digestibility of protein was 81% on these subjects with the experimental conditions. The protein requirement, however, could be cut down somewhat with some limited increaing of energy intake under parameters of N-balance and maintaining body weight. It was also observed a tendency of the requirement were getting smaller with the increase of body size.

• 한국태양에너지학회 논문집
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• 제36권4호
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• pp.49-56
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• 2016

The objective of this work is to analyze the variation in energy performance for each flat plate collector connected in series. In this study, it was assumed that solar water heating system with annual solar fraction of 60% was installed in an office building in Seoul, South Korea. The transient energy performance corresponding to four cases, which are selected using different solar radiation and outdoor air temperature, is studied by analyzing the variation in outlet temperature, solar useful heat gain, and thermal efficiency of each collector. It is observed that the useful heat gain and the collector efficiency decrease continuously, and outlet temperature increases when increasing the number of collector connected in series. The long-term performance is assessed by evaluating the thermal efficiency of each collector for two solar radiation conditions ranging from 780 to $820W/m^2$ and from 380 to $420W/m^2$. It is found that the differences between the intercept and slope of the efficiency curves for first and eighth collectors are 3.68% and 6.74% for solar radiation of $800{\pm}20W/m^2$ and 8.57% and 12.90% for solar radiation of $400{\pm}20W/m^2$, respectively. In addition, it is interesting to note that annual useful heat gain and collector efficiency are reduced with similar rate of about 6.13% when increasing the collector area by connecting the collectors in series.

• 한국간호교육학회지
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• 제15권2호
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• pp.251-259
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• 2009

Purpose: Climate change affects human health and calls for a health forecasting service. The purpose of this study was to explore the students' actual use and their satisfaction with meteorological information and the demands on health forecasting at a university in South Kyungsang Province. Method: This study used a descriptive design through structured self-report questionnaires including frequency, contents, purpose, perception, satisfaction of meterological information and need and demand of health forecasting. Data were collected from June 1 to 5, 2009 and analyzed using the SPSS 17.0 program. Descriptive statistics, t-test, ANOVA, $\chi^2$ test and Person's correlation coefficient were used to analyze the data. Result: The majority of the students watched the daily weather information to decide about daily work, outdoor activity or habitually. The mean score of need for health forecasting was $3.44{\pm}.81$, and the demand for health forecasting was $2.93{\pm}1.05$. Significant differences were found in the need for health forecasting according to sex, major, and environmental disease. In addition, the higher the satisfaction of health forecasting, the higher the demand for it. Conclusion: I suggest improving the meteorological information system technically and developing a health forecasting service resulting in a healthier and more comfortable life.

• 한국환경과학회지
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• 제12권12호
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• pp.1235-1243
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• 2003

Under controlled conditions in an environmental chamber, 24 experiments were performed to compare the ability of a Variable-Air-Volume/Bypass Filtration System(VAV/BPFS) to remove indoor pollutants and to conserve energy with the ability of conventional Variable Air Volume(VAV) system. The specific conclusions of this paper were; first, the VAV/BPFS was more efficient than the VAV system in removing particulate matter, TVOC, and target VOCs. The total effective removal rate of PM for the VAV/BPFS was two times as high as that of the VAV system. The total effective removal rate of TVOC for the VAV/BPFS was 20 percent higher than that of the VAV system. Also each target VOC concentration was reduced by using the VAV/BPFS. Second, clean air delivery rate was increased by using VAV/BPFS due to additional filtration rate. Otherwise, the VAV/BPFS decreased outdoor supply air rate above 25 percent relative to the rate of VAV system. Third, total energy consumption by the VAV/BPFS was lower than that of the VAV system during the period with indoor thermal load, occupied time. The energy saving of the VAV/BPFS ranged from 11 to 16 percent. The VAV/BPFS improves indoor air quality more efficiently than the VAV system, and it reduced energy consumption. Retrofitting the VAV system with the VAV/BPFS was easy The use of VAV/BPFS is, therefore, recommended far buildings with VAV system as well as for buildings at designing stage.

• 한국환경보건학회지
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• 제35권4호
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• pp.278-286
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• 2009

The total of 181 students in Seoul were made up questions to analysis hand washing awareness from 2007 to 2008. And their hands were sampled to isolate Staphylococcus aureus for testing antibiotic resistance. The average of hand washing frequency was $2.8{\pm}2.6$ per day in their schools. The rates of the students washing hands before eating food, after outdoor activity and after using bathroom were 22.2%, 24.4% and 49.4%, respectively. The rate of students washing hand less than 20 seconds was 64.4%. The students of 43.3% answered that they thought they were washing hands well. The middle school students were worse than elementary and high school students were aware of the frequency, duration and activity of hand washing. The isolation rate of S. aureus on the hands was 29.4%. The isolates were resitant to ampicillin (28.6%), chloramphenicol (6.1%), erythromycin (31.0%), gentamycin (2.0%), penicillin (79.6%) and tetracycline (6.1%) of 17 antibiotics tested. They were all sensitive to oxacillin and vancomycin.

• Smart Structures and Systems
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• 제7권5호
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• pp.365-378
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• 2011

Piezo-based active structural health monitoring (SHM) requires amplifiers specifically designed for capacitive loads. Moreover, with the increase in number of applications of wireless SHM systems, energy efficiency and cost reduction for this type of amplifiers is becoming a requirement. General lab grade amplifiers are big and costly, and not built for outdoor environments. Although some piezoceramic power amplifiers are available in the market, none of them are specifically targeting the wireless constraints and low power requirements. In this paper, a piezoceramic transducer amplifier for wireless active SHM systems has been designed. Power requirements are met by two digital On/Off switches that set the amplifier in a standby state when not in use. It provides a stable ${\pm}180$ Volts output with a bandwidth of 7k Hz using a single 12 V battery. Additionally, both voltage and current outputs are provided for feedback control, impedance check, or actuator damage verification. Vibration control tests of an aluminum beam were conducted in the University of Houston lab, while wireless active SHM tests of a wind turbine blade were performed in the Harbin Institute of Technology wind tunnel. The results showed that the developed amplifier provided equivalent results to commercial solutions in suppressing structural vibrations, and that it allows researchers to perform active wireless SHM on moving objects with no power wires from the grid.

• 한국버섯학회지
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• 제16권4호
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• pp.250-256
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• 2018

유럽에서 양송이 야외발효에 많이 사용하던 윈드로우 터너를 우리나라 실정에 맞게 밀짚대신 볏짚을 사용할 수 있도록 개량 개발하였다. 관행 굴삭기작업과 비교하여 조사한 결과는 다음과 같다. 교반작업 성능은 $81m^3/hr$으로 굴삭기 $28.6m^3/hr$보다 2.8배 높았으며, 재배사 한 동(균상면적 $165m^2$)당 1회 배지교반시간이 46분으로 관행보다 노력을 66% 절감할 수 있는 것으로 분석되었다. 또한 야외발효 말기 배지더미의 온도분포 조사 결과 배지더미 중앙 아래부분의 온도가 관행보다 $5^{\circ}C$ 이상 높아 호기발효에 유리한 것으로 나타났으며, 부숙도를 추정할 수 있는 회분조사결과 $30.9{\pm}1.1%$로 나타나 관행 $28.4{\pm}1.6%$보다 부숙정도도 높게 나타났다. 버섯의 농가 재배결과 수확량이 시작기의 경우 관행 대조구 대비 22.9% 증수되는 것으로 나타났다.