• 한국농림기상학회지
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• 제20권1호
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• pp.127-134
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• 2018

배추를 대상으로 고온과 침수시간에 따른 생리적 반응과 수량에 미치는 영향을 조사하기 위하여 수행하였다. 배추는 온도조건을 적온(하우스 측창 개폐온도 $20^{\circ}C$)과 고온(하우스 개폐온도 $30^{\circ}C$) 처리를 하였고, 침수처리는 무침수(0시간) 처리구와 침수처리(12, 24, 48 및 72시간)를 하였다. 그 결과 생육은 온도보다는 침수기간에 의해 유의성이 컸는데, 침수기간이 길수록 현저하게 감소하였다. 특히 결구중은 고온구일수록 침수기간이 길수록 적어졌다. 광합성속도는 $30^{\circ}C$ 12시간과 24시간 처리구와 $20^{\circ}C$ 무침수 처리구가 $22.6-23.4{\mu}mol\;CO_2{\cdot}m^{-2}{\cdot}s^{-1}$로 가장 높았고, 온도에 관계없이 72시간 침수 시에 낮아지는 것으로 나타났다. 가을배추의 정상주 비율은 침수시간이 24시간 이하일 때 88% 이상으로 높았고, 72시간 침수처리구에서는 적온구와 고온구가 각각 64와 68%로 크게 낮아졌다. 수량은 온도의 영향보다는 침수기간의 영향이 매우 컸으며 침수기간이 길수록 현저하게 감소하였다. 이것은 침수시간이 24시간까지는 어느정도 수량을 확보할 수 있지만 더 이상 길어지면 토양내 수분함량이 증가하여 뿌리호흡 및 근활력이 크게 저하되어 광합성능력까지 떨어뜨림으로써 생산성이 낮아지는 것을 의미한다. 또한 배추 재배 시 $30^{\circ}C$ 이상의 고온이 되지 않도록 하고, 고온시 침수가 되면 결구가 완전하게 되지 않았더라도 가급적 일찍 수확하는 것이 생산량 확보에 유리하다.

• 한국산업보건학회지
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• 제26권2호
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• pp.225-236
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• 2016

Objectives: Nanomaterials have been used in various fields. As use of nanoproducts is increasing, workers dealing with nanomaterials are also gradually increasing. Exposure assessments for nanomaterials have been carried out for protection of worker's health in workplace. Exposure studies were mainly focused on manufacturing processes, but these studies on after-treatment processes such as refinement, weighing, and packing were insufficient. So, we investigated exposure characteristics of particles during after-treatment processes of $Al_2O_3$ fibers and Ni powders. Methods: Mass-production of Ni powder process was carried out in enclosed capture-type canopy hood. In a developing stage, $Al_2O_3$ was handled with a local ventilation unit. Exposure characteristics of particles were investigated for $Al_2O_3$ fiber and Ni powder processes during the periods of 10:00 to 16:00, 20 May 2014 and 13:00 to 16:00, 21 May 2014, respectively. Three real-time aerosol instruments were utilized in exposure assessment. A scanning mobility particle sizer(SMPS, nanoscan, model 3910, TSI) and an optical particle counter(OPC, portable aerosol spectrometer, model 1.109, Grimm) were used to determine the particle size distribution in the size range of 10-420 nm and $0.25-32{\mu}m$, respectively. In addition, a nanoparticle aerosol monitor(NAM, model 9000, TSI) was used to measure lung-deposited nanoparticle surface area. Membrane filters(isopore membrane filter, pore size of 100 nm) were also used for air sampling for the FE-SEM(model S-5000H, Hitachi) analysis using a personal sampling pump(model GilAir Plus by 2.5 L/min, Gilian). Conclusions: For Ni powder after-treatment process, only 27% increase in particle concentration was found during the process. However, for $Al_2O_3$ fiber after-treatment process, significant exposure(1.56-3.34 times) was observed during the process.

• The Korean Journal of Pain
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• 제14권1호
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• pp.68-75
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• 2001

Background: Thoracotomy is the operation that produces the most postoperative pain, necessitating the highest requirements for postoperative analgesics. The common methods of treating postthoracotomy pain are the use of thoracic epidural analgesia, intemittent or continuous intercostal nerve blocks, intravenous narcotics and cryoanalgesia. We designed to assess the analgesic effect of epidural analgesia, cryoanalgesia and the combined analgesia in thoracic surgery. Methods: A prospective study was carried out in 59 patients undergoing elective thoracotomy for parenchymal disease. Patients were randomized into three groups: C (cryoanalgesia), CE (cryoanalgesia and thoracic epidural analgesia), E (epidural analgesia). All patients had standard anesthesia with endotracheal intubation using a double lumen endotracheal tube, and one-lung ventilation. Subjective pain relief was assessed on a visual analog scale. Analgesic requirements, complications and the degree of satisfaction were evaluated during the 7 days following surgery. Results: Subjective pain relief was significantly better in Group CE and Group E in comparison with Group C (P < 0.05). Cryoanalgesia provided a better pain score on the 6th and 7th POD than the early postoperative periods. Analgesic requirements were higher in Group C than in the Group CE and Group E during the first POD. The incidence of side effects was similar in Group CE and Group E. Conclusions: If we can reduce the concentration of fentanyl and local anesthetics in combined analgesia of epidural and cryoanalgesia, the disadvantages of each method would be overcome and would be a better method of postthoracotomy pain control.

• Asian Pacific Journal of Cancer Prevention
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• 제15권14호
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• pp.5787-5791
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• 2014

Background: With increasing survival periods and diversification of treatment methods, treatment of critically ill cancer patients has become an important factor influencing patient prognosis. Patients with cancer are at high risk of infections and subsequent complications. This study investigated the incidence and factors contributing to the development of ventilator-associated pneumonia (VAP). Materials and Methods: This retrospective study investigated the incidence of VAP and factors leading to infection in patients admitted to the intensive care unit (ICU) of a cancer center from January 1, 2012 to December 31, 2013. Results: The incidence of VAP was 2.13 cases per 1,000 days of intubation, and 13 of 288 patients (4.5%) developed VAP. Lung cancer was the most common cancer associated with VAP (N=7, 53.9%), and longer hospital stays and intubation were associated with increased VAP incidence. In the group using a "ventilator bundle," the incidence was 1.14 cases per 1,000 days compared to 2.89 cases per 1,000 days without its use; however, this difference was not statistically significant (p=0.158). Age (${\geq}65$, OR=5.56, 95% confidence interval [CI]=1.29-23.95), surgery (OR=3.78, 95%CI=1.05-13.78), and tracheotomy (OR=4.46, 95%CI=1.00-19.85) were significant VAP risk factors. The most common causative organisms were methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa (N=4, 30.8% each), followed by Acinetobacter baumannii and Candida albicans (N=2, 15.4% each). Conclusions: The incidence of pneumonia among critically ill cancer patients is highest in those with lung cancer, but lower than among non-cancer patients. The length of hospital stay and time on mechanical ventilation are important risk factors for development of VAP. Although not statistically significant, "ventilator bundle" care is an effective intervention that delays or reduces incidence of VAP. Major risk factors for VAP include age (${\geq}65$ years), surgery, and tracheostomy, while fungi, gram-negative bacteria, and multidrug-resistant organisms were identified as the major causative pathogens of VAP in this study.

• 대한의생명과학회지
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• 제17권2호
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• pp.113-122
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• 2011

Several studies have reported a relation between serum levels of uric acid and a wide variety of cardiovascular conditions. But, the relationship between serum levels of uric acid and coronary artery disease (CAD) is still controversial. The present study was retrospectively designed to investigate whether CAD can be stratified by the level of uric acid and there are the relationships between preoperative levels of uric acid and perioperative biochemical markers in fifty-adult patients that underwent coronary artery bypass grafting surgery (CABG) and twenty-normal subjects. They were divided into the control, the unstable angina (UA-group) and the myocardial infarction group (MI-group). In preoperative levels of uric acid, the MI-group was higher than control and the UA-group. The MI-group had significantly higher correlations than the UA-group between preoperative levels of uric acid and left ventricular ejection fraction, cardiac markers (creatine kinase, lactate dehydrogenase and brain natriuretic peptide), renal markers (blood urea nitrogen and creatinine) or total leukocyte levels. At postoperative periods, the MI-group had higher relationships of uric acid with aspartate aminotransferase, blood urea nitrogen or creatinine levels. Although there was not statistically significant, the UA-group tended to have higher correlation coefficients than the MI-group between preoperative levels of uric acid and intensive care unit-stay (ICU), or postoperative mechanical ventilation time. These results reflect that increased levels of serum uric acid may be a tool for the diagnosis of coronary heart disease and may be considered as a good predictor in assessing the cardiac and renal functions in patients with myocardial infarction or unstable angina at the preoperative period. However, further studies should be performed in a large patient population.

• 한국의류학회지
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• 제28권6호
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• pp.795-806
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• 2004

Unripe indigenous persimmons which contain rich tannins have been used as natural dye materials traditionally and have been using continuously for dyed clothes named Gal-ot in Jeju. Those persimmons were cheap and easy to use as dyes because of inedible and widely cultured in Korea. Persimmon juice dyes not only make fabrics brown-color but also give functional and hygienic properities such as stiffness, air ventilation of clothes, antibacterial activity, protectivity against ultraviolet light. However there are several serious problems which are ristriction of dyeing periods, longtime irradiation, uneven color and low color fastness etc. in persimmon juice dyeing. This study purpose to improve dye effect and method in order to enlarge useability of persimmon juice dyeing. Cotton fabrics were pad-dyed to 100% pick-up using padding machine after dipping in persimmon juice extracted from unripe persimmons indigenous from Jeju. It was possible and available to control pick-up rate. The color of dyed cotton fabrics by padding method was more even and repeatable than which by traditional hand method. Persimmon juice concentrations were 4 types of 10, 25, 50 and 100％. The more concentration increased, the more color deepened. UV Irradiation instead of sunlight was applied to color developing. Irradiation times were shortened till 1∼8 hrs. Same color values could be taken without water wetting which were required in sunlight irradiation. Tensile strengths of cotton fabrics pad-dyed with low concentration of persimmon juice decreased but recovered at high concentrations. Elongations(％) of cotton fabrics pad-dyed with persimmon juice were increased 1％ more than undyed cotton in sunlight irradiation. Drape stiffness increased upto double times as much as.

• 한국농공학회논문집
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• 제64권5호
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• pp.27-39
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• 2022

The smart farm is recognized as a solution for future farmers having positive effects on the sustainability of the poultry industry. Intelligent microclimate control can be a key technology for broiler production which is extremely vulnerable to abnormal indoor air temperatures. Furthermore, better control of indoor microclimate can be achieved by accurate prediction of indoor air temperature. This study developed predictive models for internal air temperature in a mechanically-ventilated broiler house based on the data measured during three rearing periods, which were different in seasonal climate and ventilation operation. Three machine learning models and a mechanistic model based on thermal energy balance were used for the prediction. The results indicated that the all models gave good predictions for 1-minute future air temperature showing the coefficient of determination greater than 0.99 and the root-mean-square-error smaller than 0.306℃. However, for 1-hour future air temperature, only the mechanistic model showed good accuracy with the coefficient of determination of 0.934 and the root-mean-square-error of 0.841℃. Since the mechanistic model was based on the mathematical descriptions of the heat transfer processes that occurred in the broiler house, it showed better prediction performances compared to the black-box machine learning models. Therefore, it was proven to be useful for intelligent microclimate control which would be developed in future studies.

• 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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• 제29권1호
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• pp.43-51
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• 2023

Purpose: To accommodate the increasing number of patients during the COVID-19 pandemic, numerous portable HEPA filter units (PHUs) were installed in the general wards of existing medical facilities(EMFs) to convert them into emergency conversion facilities (ECFs). The purpose of this study was to build a dataset in preparation for emerging infectious diseases in the post-COVID-19 era by analyzing the construction and operation of ECFs. Methods: Field investigations were conducted during ECF operation periods based on the analysis of heating, ventilation, and air conditioning (HAVC) system design documents for six ECFs across Korea. Interviews were conducted with facility managers during the field investigations. Results: When constructing an ECF within an EMF, the installation status and characteristics of the existing system should be considered. Field investigations and verifications of the operation of HAVC systems must be conducted beforehand for smooth ECF operations. If heating and cooling are required with indoor air circulation type equipment in an ECF zone, the implementation of a heating and cooling method that can satisfy the comfort requirements of the occupants while minimizing cross-contamination is essential. When using PHUs that do not meet the performance standards required by medical equipment, the noise level resulting from such equipment operation must be evaluated and improved. Implications: For EMFs, various guidelines that can be referred to for the construction and operation of ECFs must be developed to prepare for emerging infectious diseases in the future.

• 한국대기환경학회지
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• 제26권5호
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• pp.543-553
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• 2010

Almost five million citizens a day are using subways as a means of traffic communication in the Seoul metropolitan. As the subway system is typically a closed environment, indoor air pollution problems frequently occurs and passengers complain of mal-health impact. Especially $PM_{10}$ is well known as one of the major pollutants in subway indoor environments. The purpose of this study was to compare the indoor air quality in terms of $PM_{10}$ and to quantitatively compare its source contributions in a Seoul subway platform before and after installing platform screen doors (PSD). $PM_{10}$ samples were collected on the J station platform of Subway Line 7 in Seoul metropolitan area from Jun. 12, 2008 to Jan. 12, 2009. The samples collected on membrane filters using $PM_{10}$ mini-volume portable samplers were then analyzed for trace metals and soluble ions. A total of 18 chemical species (Ba, Mn, Cr, Cd, Si, Fe, Ni, Al, Cu, Pb, Ti, $Na^+$, $NH_4^+$, $K^+$, $Mg^{2+}$, $Ca^{2+}$, $Cl^-$, and ${SO_4}^{2-}$) were analyzed by using an ICP-AES and an IC after performing proper pre-treatments of each sample filter. Based on the chemical information, positive matrix factorization (PMF) model was applied to identify the source of particulate matters. $PM_{10}$ for the station was characterized by three sources such as ferrous related source, soil and road dust related source, and fine secondary aerosol source. After installing PSD, the average $PM_{10}$ concentration was decreased by 20.5% during the study periods. Especially the contribution of the ferrous related source emitted during train service in a tunnel route was decreased from 59.1% to 43.8% since both platform and tunnel areas were completely blocked by screen doors. However, the contribution of the fine secondary aerosol source emitted from various outside combustion activities was increased from 14.8% to 29.9% presumably due to ill-managed ventilation system and confined platform space.

• Pediatric Infection and Vaccine
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• 제23권2호
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• pp.87-93
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• 2016

목적: 신생아 중환자실(neonatal intensive care unit, NICU)에서 인플루엔자 바이러스 집단 발병의 보고는 흔하지 않으며 그 증상은 다양하다. 저자들은 국내 단일기관 NICU에서 발생한 A형 인플루엔자 바이러스 감염의 집단발병에 대해 보고하고 신생아 특히 미숙아에서의 임상적 특성을 알아보고자 하였다. 방법: 2011-2012년 국내 인플루엔자 바이러스 감염 유행 시기에 고신대학교 복음병원 NICU에 입원한 환자들 중 인플루엔자 바이러스 RT-PCR 검사를 시행한 29명 환자들의 의무기록을 후향적으로 조사하였다. 결과: 대상 환자 중 11명에서 A형 인플루엔자 바이러스 양성이었는데(37.9%), 모두 미숙아였고 이들 중 3명(27%)은 증상이 없었으며 상기도 감염 증상 없이, 발열(18%, 2/11), 호흡곤란(72.7%, 8/11), 소화기 증상(27.3%, 3/11)이 있었다. 증상 소실까지 기간의 중앙값은 5일이었다. 이들은 모두 합병증 없이 생존하여 퇴원하였다. A형 인플루엔자 바이러스 RT-PCR 양성군과 음성군 사이에 검체 채취시 재원기간, CRIB 점수, 기계환기 과거력, 덱사메타손 사용 과거력의 차이가 있었다. 결론: 신생아 특히 미숙아에서 A형 인플루엔자 바이러스 감염의 증상은 비특이적이므로 지역 내 인플루엔자 유행시기에는 NICU 입원 중인 신생아에서 감염질환의 원인 병원체로 인플루엔자 바이러스를 고려해야 한다.