• 한국구조물진단유지관리공학회 논문집
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• 제18권3호
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• pp.93-100
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• 2014

본 연구는 교량의 상시계측자료인 고유진동수 및 고유모드를 기준으로 계측기반모델을 구성하고, 구조해석을 수행하여 교량 공용상태에서 사장케이블 장력평가를 수행하였다. 케이블 설치 위치에 따라 하중유형별 케이블 장력이 다르다는 것을 알 수 있다. 고정하중과 활하중에 의한 케이블 계측장력은 케이블 설치위치에 따라 차이가 크지 않으나 설계하중을 적용한 해석결과보다 큰 값을 나타낸다. 계측기반모델에 대한 케이블장력분포는, 설계모델에 대한 장력보다 크지만, 계측장력과 유사한 분포를 나타낸다. 그러므로 장기거동을 고려하여 사장교 케이블설계는 계측기반모델의 해석결과를 반영할 필요가 있다. 이를 위하여 많은 계측자료를 이용한 장기거동 분석연구가 요구된다.

• 한국분무공학회지
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• 제8권2호
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• pp.1-6
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• 2003

The liquid phase LPG injection (LPLI) system (the third generation technology) has been considered as one of the next generation fuel supply systems for LPG vehicles, since it has a very strong potential to accomplish the higher power, higher efficiency, and lower emission characteristics than the mixer type(the second generation technology) fuel supply system However. when a liquid LPG fuel is injected into the inlet duct of an engine, a large quantity of heat is extracted due to evaporation of fuel. This leads to freezing of the moisture in the air around the outlet of a nozzle, which is called icing phenomenon. It may cause damage to the outlet nozzle of an injector or inlet valve seat. In this work, the experimental investigation of the icing phenomenon was carried out The results showed that the icing phenomenon and process were mainly affected by humidity of inlet air instead of air temperature in the inlet duel. Also, it was observed that the total ice formed around the nozzle weighs at about $150mg{\sim}260mg$ after injection for ten minutes. And some fuel species were found in the ice attached at the front side of a nozzle, while frozen ice attached at the back of a nozzle was mostly' consisted of moisture of inlet air. Therefore, some frozen ice deposit. detached from front nozzle of an injector, may cause a problem of unfavorable air fuel ratio control in the small LPLI engine.

• 한국과학교육학회지
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• 제5권1호
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• pp.63-79
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• 1985

The purpose of our survey study was to investigate the status on perception and actual state toward science educational evaluation and objectives of middle school science teachers in Pusan. The perception and actual state were surveyed by the questionaire which was developed by Jong-Ok Woo et. al. We developed two kinds of questionaire. One is designed to use Likert type scale and is composed of two main category(SE; Science educational evaluation, SO; Science educational objectives) which contains 21 question items, and the other has 16 question items From 313 science teacger's responses of 75 middle schools in pusan, the tendency. of total(SE+SO) and each sub category, and the contrast with their background and actual state were analized by SPSS program of KAIST. Some results of our survey study can be summarized as follows; 1. Total tendency of science educational evaluation(SE) and objectives(SO) of middle school science teachers in pusan shows a positive and right tendency of conception in general(m-85.8/100). 2. Tendency of SE(m-87.8/100) are slightly higher than SO(m-81.7/100). At the level of 5% significance, there are correlated but shows low correlation (r=0.12(4). 3. In each correlation toward total tendency(SE+SO), SE is highly correlated(r-0.8486) but SO is moderately correlated(r=0.6297) at the level of 0.1% significance. 4. Tendencies of 5sub category (PE, PC, PD, PO, PB) shows considerably right tendencies (m=$73.4/100{\sim}92.7/100$), there are moderately correlated foward total tendency(SE+SO) at the level of 0.1% significance (r=$0.49{\sim}0.60$). 5. At the level of 5%significance, total means are no differences which their background(Sex, Final alma mate, Major, Difference of training), but there is differences to teaching career at the level of 5% significance.

• 대한화장품학회:학술대회논문집
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• 대한화장품학회 2003년도 IFSCC Conference Proceeding Book II
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• pp.87-107
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• 2003

It was demonstrated that Transactivating transcriptional activator(TAT) protein from HIV-1 shown to enter cells when added to the surrounding media. TAT peptide chemically attached to various proteins was able to deliver these proteins to various cell and even in tissues in mice with high levels in heart and spleen. In this study, the tripeptide GKH(Glycine-Lysine-Histidine) derived from Parathyroid hormone (PTH), which was known as lipolytic peptide, is attached to 9-poly Lysine(TAT) to be used as a cosmetic ingredient for slimming products. When Glycerol release, expressed as extracellular glycerol concentration, is lipolysis index, TAT-GKH at $10^{-5}$mo1/L induces approximately 41.5% maximal lipolytic effects in epididymal adipocytes isolated from rats, compared with basal lipolysis. Epididymal adipose tissues of male rats is assessed ex vivo by microdialysis. Probes are perfused with Ringer solution in which increasing concentrations of TAT-GKH. The perfusion of TAT-GKH induces lipolytic effect. Penetration study showed that TAT-GKH efficiently elevates 36 times higher penetration into the excised hairless mice skin than GKH. in vivo study showed that TAT-GKH had a better effect upon the relative volume of eye bag after 28 days of application on twenty(+2) healthy female volunteers. It was identified that TAT-GKH increases penetration enhancement and lipolytic effects in both in vitro, ex vivo and in vivo.

• 한국산학기술학회논문지
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• 제16권11호
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• pp.7629-7634
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• 2015

이 연구의 목적은 일제강점기 공통도면을 사용해 계획된 군청사에 대해 본가-부속가 연결방식을 기준으로 그 배치유형을 정리하고 각 유형별 증 개축 방향을 고찰하는 것이다. 우선, 디지털이미지로 제공되는 국가기록원 소장 1910년대 작성된 군청사 관련 건축도면을 분석하여 공통형 군청사의 배치유형 세 가지를 확인하고, 기타 자료를 통해 두 가지 배치유형을 추가발굴한다. 이어서, 각 배치유형을 본가-부속가 연결방식을 기준으로 세분한 후 그 증 개축경향을 정리한다. 연구방법은 군청사 관련 건축도면 디지털이미지, 그 해제, 조선총독부와 각 도가 주고받은 문서, 신문과 잡지의 기사 도면 사진 등을 분석하는 문헌연구방법이다. 공통형 군청사의 다섯가지 배치유형은 13가지로 세분되고, 각 세분된 유형에서 증 개축은 각 부지의 지형 형상 기타 사정에 따라 달랐지만, 본가는 신축 및 증 개축 상황에서 항상 전면 중앙에 위치하여 관청사로서 상징성과 중심성을 유지하려는 노력은 일관된다. 공통형 군청사의 계획은 1930년대 초반까지도 꾸준히 이어진다.

• Journal of Biosystems Engineering
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• 제26권5호
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• pp.441-448
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• 2001

Hot air heater with light oil combustion is used as the most common heater for greenhouse heating in the winter season. However, exhaust gas heat discharged to atmosphere through chimney reaches up to 10~20% of total heat capacity of the oil burred. In order to recover the heat of this exhaust gas and to use for greenhouse heating, the heat pipe type exhaust heat recovery system was manufactured and tested in this experiment. The system consisted of a heat exchanger made of heat pipes, ø15.88${\times}$600mm located in the rectangular box of 675(L)${\times}$425(W)${\times}$370(H)mm, an air suction fan and air ducts. The number of heat pipe was 60, calculated considering the heat exchange amount between exhaust gas and air and heat transfer capacity of a heat pipe. The working fluid of heat pipe was acetone because acetone is known for its excellent heat transfer capacity. The system was attached to the exhaust gas path. According to the performance test it could recover 53,809 to 74,613kJ/h depending on the inlet air temperature of 12 to -12˚at air flow rate of 1.100㎥/h. The temperature of the exhaust gas left the heat exchanger dropped to 100$^{\circ}C$ from 270$^{\circ}C$ after the heat exchange between the suction air and the exhaust gas.

• 한국정보전자통신기술학회논문지
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• 제8권3호
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• pp.229-238
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• 2015

본 연구는 이러한 경사 토지와 경사진 도로 측면 등 다양한 영역에서 작동하는 캔을 구현 잡초의 전자 제어 시스템을 개발 하였다. 잡초 구현은 다섯 가지 주요 부분으로 구성 전자 제어 시스템, 유압 시스템, 메인 프레임, 붐 및 팔을 이용하는 기계와 회전형 제초기. 그리고 잡초는 전자 제어 시스템의 사용을 고려 트랙터의 3 점 히치 의해 부착될 수 있도록 개발되었다 구현한다. 그 결과, 전자 제어 시험 제초 구현 경사 땅 트랙터에 장착하여 실시했다. 전자 제어 시스템의 테스트 결과가 만족 제초 성능을 보여 주었다.

• 한국조경학회지
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• 제13권1호
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• pp.1-24
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• 1985

The pinus trees planted by the road in the Seoul -Suwen high-way was surveyed on the damages due to air pollution during April and May in 1984. The results were as follows ; The concentration of SO$_2$was ranged from 0.003 to 0.05ppm, NOx from 0.03 to 0.1ppm and the amount of dust fall, from 10 to 110ton/km$^2$/month. While the concentrations of gaseous pollutants such as SO$_2$and NOx were notsignificantly different in the type of road and with in the distence of 20 meters from the road the dust falls were decreased as remoted from the road. The tissue damages of leaves were determined by the microscopic observation. The higher concentration of dust fall on the leaf, the more severe damage observed in the stomata. The attached dust of the leaves were ranged from 1l to 75mg/g of leaf, and those were significantly incereased as near from road. The sulfur contents of leaves were measured at 0.15g/100g of leaf in the 5 meters located and at 0.064g/100g of leaf in the 20 meters, and the lead contents, 45ug/g of leaf in the 5 meters and 24ug/g in the 15 meters. The appearent damages of plant were very much corelated to the attached dusts of leaves the sulfur contents and the amount of dust fall, and the multiple regression analysis between the damages and factors of air pollution were under taken. As increment of vehicle in future, the air Pollution was predicted and the plant damages were estimated.

• 대한영양사협회학술지
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• 제27권4호
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• pp.209-231
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• 2021

The purpose of this study was to compare differences between essential tasks and delegable tasks among public kindergarten dietitians. A survey study was conducted through a self-administered online method from November 18 to December 28, 2019. The survey consisted of essential tasks and delegable tasks, including 6 Duties, 25 Tasks, and 94 Task Elements. The survey was distributed to a sample of 500 kindergartens in Korea, after excluding incomplete surveys and outliers, and a total of 224 responses were used for the analysis. Descriptive statistics were used to compare essential tasks and delegable tasks. The results show that 'Duty A. Nutrition Management', 'Duty B. Foodservice Management Practices', 'Duty C. Hygiene management of kindergarten foodservice', 'Duty D. Nutrition-Diet Education and counseling', and 'Duty F. Professionalism Enhancement' were recognized as essential tasks to be performed by kindergarten dietitians. All 16 tasks elements (100.0%) in 'Duty E. Managing snacks during semesters, and lunch/snack during breaks' were identified as delegable tasks. In conclusion, most tasks were recognized as essential tasks to be performed by kindergarten dietitians. On the other hand, 'Duty E. Managing Snacks during semesters, and lunch/snack during breaks' was considered a delegable task by public-attached kindergarten dietitians. It is recommended that public-attached kindergartens should consider additional workforce related to 'Duty E'. This study is expected to offer basic data on laws and regulations about the duties of kindergarten dietitians.

• 한국기계가공학회지
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• 제20권12호
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• pp.30-35
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• 2021

In this study, we developed an automatic module changer for agricultural implements for using in unmanned agricultural robots. An automatic module changer is attached by lowering from the top to bottom of the implements and fixing the four fastener bars attached to the implements in combination. The lift function was implemented using seesaw-type structures to keep the engagement point constant when the automatic module changer climbs and descends, and the switching function of the automatic module changer was implemented using the link device in the cam structure. We developed an algorithm to check the presence of attachment and opening/closing of the workpiece using limit switches and verified the performance through combination assessment and weight lift test to assess whether the combination was within the error range.