• 한국수산과학회지
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• 제54권5호
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• pp.751-760
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• 2021

This study investigated the changes in water quality parameters and microbial colonies when ozone was applied to a semi-recirculating aquaculture system (semi-RAS) for the olive flounder Paralichthys olivaceus (500 g in average weight). Concentrations of ozone-produced oxidants (OPO) in rearing tanks were maintained at 0, 0.014, 0.025 mg/L as Cl₂ for 26 days. Except total ammonia nitrogen, nitrite nitrogen, nitrate nitrogen, phosphate phosphorus, chemical oxygen demand, and total suspended solids decreased significantly with increasing OPO concentration in daily and weekly monitoring (P<0.05). Colony forming unit (CFU) counts of heterotrophic marine bacteria decreased in an OPO concentration-dependent manner. Overall reduction rates of microbial colonies in the treatments were 80% higher than those of the control (P<0.05). During the experiment, the OPO concentration-driven ozonation was reliably practiced without any adverse effects on the animals cultured in semi-RAS. Considering the biohazard, operating cost, and stability of ozonation, an OPO concentration of 0.014 mg/L would be sufficient to control water quality parameters and microbial colonies in a semi-RAS.

• 한국식품위생안전성학회지
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• 제34권4호
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• pp.348-353
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• 2019

LC/MS/MS를 이용하여 2019년 1월부터 6월까지 서울 강서지역에 유통하는 콩나물 및 숙주나물 82건에 대한 카벤다짐 모니터링을 실시한 결과 숙주나물에서는 카벤다짐이 검출되지 않았으며 콩나물에서는 59건중 6건에서 카벤다짐이 검출되어 10.2% 의 검출율을 나타내었다. 카벤다짐이 검출된 콩나물 6건중 5건이 허용기준을 초과하여 검출건수 대비 83.3%의 부적율을 나타내었다. 검출된 카벤다짐의 농도는 최소 0.012 mg/kg, 최대 0.104 mg/kg, 평균 0.063 mg/kg 이었으며 6건중 5건이 재래시장에서 유통되는 비포장 제품이었다. 카벤다짐이 검출된 6건의 원료수입국은 수입산이 3건, 출처불명이 3건 이었으며 국내산으로 표시된 제품은 없었다. 카벤다짐이 검출된 콩나물에 대한 위해성 평가결과 %ADI 값이 1 이하로 인체에 미치는 위해도는 안전한 수준인 것으로 평가되었다.

• Journal of information and communication convergence engineering
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• 제17권1호
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• pp.74-83
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• 2019

This study designs a squat posture recognition system that can provide correct squat posture guidelines. This system comprises two modules: a Kinect camera for monitoring users' body movements and a Wii Balance Board(WBB) for measuring balanced postures with legs. Squat posture recognition involves two states: "Stand" and "Squat." Further, each state is divided into two postures: correct and incorrect. The incorrect postures of the Stand and Squat states were classified into three and two different types of postures, respectively. The factors that determine whether a posture is incorrect or correct include the difference between shoulder width and ankle width, knee angle, and coordinate of center of pressure(CoP). An expert and 10 participants participated in experiments, and the three factors used to determine the posture were measured using both Kinect and WBB. The acquired data from each device show that the expert's posture is more stable than that of the subjects. This data was classified using a support vector machine (SVM) and $na{\ddot{i}}ve$ Bayes classifier. The classification results showed that the accuracy achieved using the SVM and $na{\ddot{i}}ve$ Bayes classifier was 95.61% and 81.82%, respectively. Therefore, the developed system that used Kinect and WBB could classify correct and incorrect postures with high accuracy. Unlike in other studies, we obtained the spatial coordinates using Kinect and measured the length of the body. The balance of the body was measured using CoP coordinates obtained from the WBB, and meaningful results were obtained from the measured values. Finally, the developed system can help people analyze the squat posture easily and conveniently anywhere and can help present correct squat posture guidelines. By using this system, users can easily analyze the squat posture in daily life and suggest safe and accurate postures.

• 정보처리학회논문지:컴퓨터 및 통신 시스템
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• 제8권4호
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• pp.93-102
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• 2019

웰니스에 대한 관심이 증대됨에 따라 개인의 건강상태를 웨어러블 디바이스로 모니터링하는 연구들이 늘어나고 있다. 이에 따라 웨어러블 디바이스에서 운동과 일상 활동을 구분하는 다양한 방법들이 연구되어 왔다. 이러한 기존 연구는 대부분 기계학습을 활용한 방식이다. 하지만 개인별 학습 데이터에 의존적인 과적합 문제와 연속적인 사건으로 구성되는 사람의 행동을 독립적으로 취급하여 인식 결과가 중간에 끊기고 오인행동이 생기는 문제가 있다. 이에 본 연구는 운동 시 심박이 오르내리는 생체반응 원리를 기반으로 한 운동 상태 검출 방법을 제안한다. 제안하는 방법은 3축 가속도 센서와 PPG 센서를 통해 활동강도 및 심박 수를 산출하여 심박 회복기를 판단한 후, 활동강도 검사 또는 심박 상승기 검사를 통해 운동 상태를 검출한다. 실험 결과에서 제안하는 알고리즘은 평균 정확도 98.64%, 정밀도 98.05%, 재현율 98.62%로 기존 알고리즘보다 개선된 모습을 보였다.

• 실내환경 및 냄새 학회지
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• 제17권4호
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• pp.315-321
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• 2018

Phthalate is an endocrine disruptor that interferes with homeostasis and developmental regulation. It is highly toxic to the environment and is associated with various diseases of the human body. Using biological samples from 140 adult subjects, to evaluate the influencing factors which are related to contaminant concentration levels, we used correlation analysis and multiple regression analysis. Lastly, in order to analyze the health effects related to exposure to phthalates, we conducted a risk assessment by estimating acceptable daily intake exposure according to the influential factors. When we compared the concentration level according to influential factors, in general, the subjects who had engaged in home remodeling work had higher urinary phthalate metabolite concentrations levels than the subjects who had not engaged in home remodeling work. We can confirm statistically significant differences in DBP metabolites. In addition, we can confirm the concentration appeared higher in the categories such as using air freshener, sofa and foods. Through conducting a risk assessment of DEHP, BBzP, DiBP, and DnBP by using data on phthalate metabolite concentration in urine, it was found that the average concentration of all metabolites did not exceed TDI.

• 대한건축학회논문집:계획계
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• 제34권11호
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• pp.75-84
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• 2018

This study analyzed users' acceptance and intention to use in addition to needs and preferences of smart home technologies, and identified the differences in technology preference and acceptance by different factors. The subjects were residents in the 40s and 60s residing in the Seoul or suburbs of Seoul, and questionnaires were conducted in the 40s while interviews with questionnaires were conducted in the 60s. A total of 105 questionnaires were used as data, and frequency, mean, crossover, independent sample t test, one-way ANOVA and multiple regression analysis were performaed using SPSS23. The results of this study are as follows. First, hypertension, hyperlipidemia and hypercholesterolemia were the most common diseases among respondents and if there was no discomfort, they would like to continue living in the homes of the current residence. Therefore, the direction of smart home development should support the daily living and health care so that residents can live a healthy life for a long time in their living space. Second, the technologies that residents most need were a control technology of residential environments and a monitoring technology of residents' health and physiological changes. The most preferred sensor types are motion sensors and speech recognition while video cameras have a very low preference. Third, technology anxiety was the most significant factor influencing intention to accept smart home technology. The greater the technology anxiety is, the weaker the acceptance of technology. Fourth, when applying smart residential technology in homes, various resident characteristics should be considered. Age and technology intimacy were the most influential variables, and accordingly there were differences in technology preference and acceptance. Therefore, a user-friendly smart home plan should be done in the consideration of the results.

• 한국수자원학회논문집
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• 제54권6호
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• pp.381-393
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• 2021

국립재난안전연구원의 재난안전 신기술 공적개발원조(ODA) 사업의 일환으로 2019년 라오스 볼리캄싸이주 남싼강유역의 보리칸을 대상으로 홍수예경보시스템을 구축하였다. 미계측 중소하천유역인 대상 지역에 강우량와 유출량의 실시간 관측을 위한 관측소 및 경보국을 설치하였으며, 실시간 자료 관리와 홍수예경보 기능 등을 수행하는 소프트웨어도 개발되었다. 홍수경보 기준 설정 및 홍수예측을 위한 nomograph 개발을 위해 대상 지역의 30년 치 연도별 최대 일강우량자료와 하천측량성과를 바탕으로 수리·수문분석을 수행하였다. 본 논문은 시스템 구축 과정과 방법론을 소개하고, 시스템 설치 후 2020년 실시간 관측 수집된 자료들을 바탕으로 수행한 시스템의 적용성 검토 결과를 제시하였다.

• 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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• 제27권2호
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• pp.57-64
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• 2021

Purpose: The relationship between the staff area and the patient's private area is the key factor in designing the structure and the environmental characteristics of ward spaces in a psychiatric hospital. Recent research has found that for the purpose of treatment and securing privacy, psychiatric patients need to be in an open space of relief rather than closed confined environment and under the watch of nursing staffs. Methods: A survey at three kinds of wards in a private psychiatric hospital in Japan was conducted in October 2002. These wards include an acute ward, a psychiatric convalescence ward, and a stress care ward. All three kinds of wards have the same structure. At each ward, spatial preferences of the 145 psychiatric inpatients were surveyed and data concerning the patient's diagnostic category, symptoms, and activities of daily living were recorded. Results: The patients in the stress care ward prefer to stay in private spaces than public spaces. On the other hand, in the acute ward the patients seem to have a preference between managed public spaces where are monitored by nursing staffs and their private rooms where the nurse station is close. In addition, the patients in the psychiatric convalescence ward spend most of their time in the public space, such as the hallways or the day room. Implications: Base on this research, the spaces at the acute ward that could be monitored by the nursing station serves effectively as a safety space for patients was concluded. However, in the stress care ward, the patients may perceive the monitoring by the nursing staff as interruption or nuisance to their relaxation. In order to design an ideal healing environment for psychiatric patients in psychiatric ward, it is important to consider how environmental characteristics of space affect the environmental sense of patients in each ward.

• 한국지형학회지
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• 제25권4호
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• pp.89-101
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• 2018

In Mt. Halla, an arctic-alpine plant Diapensia lapponica var. obovata largely clings to rock surfaces. We observed the rock-surface temperatures of a rocky ridge on the summit area of the mountain from late April 2009 to early May 2010 in order to examine the diurnal and annual temperature variations and the thermal amplitude. We also investigated temperature regimes such as the frequency of freeze-thaw cycles and the temperature change, which might endanger the habitat through frost weathering. For comparison of slope aspects, temperature monitoring was carried out on the north and south faces of the same rocky ridge. The south face experiences the high daily maximum rock-surface temperatures and the high thermal amplitudes during the unfreezing season of May to November 2009. The temperature regimes are considered to exert physiological stress to the arctic-alpine plant. In addition, the south face shows the high frequency of freeze-thaw cycles during the seasonal freezing period of December 2009 to April 2010. This indicates that the south face is susceptible the exfoliation and granular disintegration of rock surfaces, which results in habitat destruction. As a consequence, the south face is believed to be less favorable for the establishment and growth of the arctic-alpine plant than the north face on the summit area of Mt. Halla.

• 대한방사선기술학회지:방사선기술과학
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• 제44권3호
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• pp.247-252
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• 2021

As the number of single-person households increases, the consumption of bottled water is increasing. In addition, as the public's interest in radioactivity increases, interest in the field of living radioactivity is also increasing. Since drinking water is an essential element in our daily life, it must be safe from radioactivity. In this study, gamma radiation of drinking spring water was measured and internal exposure dose evaluation was performed to determine its harmfulness. K-40 and uranium-based radioactivity analysis was performed through a high-purity germanium detector, and as a result, drinking water was detected somewhat higher than that of mixing water. Since there is no regulation on the natural radioactivity concentration in Korea, it was compared with the U.S. Environmental Protection Agency Drinking Water Regulations and World Health Organization standard. As a result, there were some items that exceeded standards. Internal exposure was evaluated according to the effective dose formula of ICRP 119. As the result was derived that a maximum of 1.17 mSv per year could be received. This result means that the dose limit for the general public may be exceeded, and it was judged that it is necessary to set an appropriate standard value and present a recommendation value through continuous monitoring in the future.