• 한국환경보건학회:학술대회논문집
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• 한국환경보건학회 2003년도 Challenges and Achievements in Environmental Health
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• pp.174-176
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• 2003

A survey was conducted to investigate the sanitary condition of school kitchens in one region of Korea. A self-administered questionnaire recommended by the Korea Ministry of Education & Human Resources Development (MOEHRD) was offered to a random sample of dieticians of twenty-five elementary schools for food, sanitation and safety inspection of their kitchens. Air temperature, relative humidity, and airborne microbes in the kitchens were monitored during food preparation, processing and service. The inspection results showed their sanitary condition met the level B of the recommendation of the Korea MOEHRD. The range of air temperature of the kitchens was 21.4∼22.4$^{\circ}C$, and the range of relative humidity was 62.4∼69.6%. The microbiological evaluation of kitchen samples indicated aerobic plate count levels from 22.5 to 26.5 CFU/15 min. These results indicate that the levels of sanitary condition of kitchens in the schools were not satisfactory for safe foodservice although the inspection showed good results. This study suggests that the school kitchens should be monitored and strict inspection is necessary.

• 한국안전학회지
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• 제29권4호
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• pp.61-72
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• 2014

The aim of this study is to define the condition of optimal pre-treatment for preferable activated carbon fibers (ACFs), which are based on rayon fibers. This paper shows the ideal path of ACFs preparation process; implies that rayon fibers are pre-treated by various solvents with different times before the heating process. The pre-treated rayon fibers finally turned into desirable rayon fiber-based ACFs through optimal pre-treatment condition by heating processes. The thermal analysis method of pre-treated rayon fibers by thermo-gravimetry analyser (TGA) is an idealized tool, which analyzes the best thermal condition of pre-treatment process. Surface morphologies of resulting rayon fibers based ACFs were examined by scanning electron microscope(SEM). The results of TGA and SEM analyses show that the optimal pre-treatment condition for preparing ACFs was clearly defined, in terms of thermal stability and surface morphology.

• 한국세라믹학회지
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• 제25권6호
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• pp.677-684
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• 1988

Titania powders were obtained from the various hydrolysis condition the variation of Alkoxide, water/Alcohol, REaction, Temp., reaction time and solvent system were investigated. In this result, spherical monodisperesed titania gel powders(≒0.7${\mu}{\textrm}{m}$) were obtained using EtOH(as solvent), and this method had rapid reaction time compare with iso-PrOH(as solvent).

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 추계 학술발표회 제16권2호
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• pp.445-448
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• 2004

Recently, bridge deck overlay with latex modified concrete is widely applied in domestic. the capacity of bridge deck overlay depends on bond state on the surface. factors that have an effect on bond state are clean condition on the surface, absence of surface microcracking, absence of laitance, overlay curing. In this study, it is researched that characteristic of bond strength according to moisture condition on the surface and the removal method of concrete. As a result, it shows high bond strength in dry condition when w/c is $31\%$ and in moisture condition when w/c is $38\%$ respectively. characteristic of bond strength according to the removal method of concrete shows high bond strength when using water-jets rather than jackhammers.

• 한국수산과학회지
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• 제28권4호
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• pp.392-396
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• 1995

Chitosan의 탈아세틸화도와 분자량에 미치는 chitosan 제조조건의 영향을 조사한 결과는 다음과 같다. 탈아세틸화 과정에서 NaOH 농도가 높을수록 탈아세틸화는 많이 일어났으나 $40\%$ 이상의 농도에서는 농도가 증가할수록 탈아세틸화의 증가폭은 감소하고, 분자량의 감소폭은 줄어들지 않았다. 가열온도를 $130^{\circ}C$ 에서 $150^{\circ}C$로 증가시켰을 때 탈아세틸화도는 $84\%$에서 $87\%$로 $3\%$ 정도 증가한 반면 분자량은 267,000에서 85,800로 $90^{\circ}C$에서 $130^{\circ}C$로 증가하였을 때의 분자량 감소폭보다 크게 나타났다. 그리고 3시간 이상 연속 알칼리처리하여도 $86\%$ 이상의 탈아세틸화도를 얻지 못하였지만 간헐적으로 수세하여 처리한 경우 3회 처리하였을 때 $93\%$의 탈아세틸화가 일어났다. 연속으로 3시간 처리했을 경우 탈아세틸화도는 $84\%$이었고, 분자량은 267,000이었으나 간헐반복처리로 3시간처리 했을 때는 탈아세틸화도가 $93\%$, 분자량은 280,000으로 연속처리 한 경우보다 더 높았다.

• 소음진동
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• 제22권4호
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• pp.28-32
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• 2012

Condition-based maintenance on wind turbines not only involves maintenance, but also encompasses servicing, inspection, measurement and evaluation of the condition of the unit. The current condition can be evaluated on the basis of machine-specific overall vibration values. Until now, overall vibration values had not been defined for wind turbines. In fact, ISO 10816-3 explicitly excludes wind power plants. The new VDI 3834 closes this gap shown in Sheet 1: Vibration values for wind turbines up to 3 MW. In addition to the new VDI 3834 is the ISO 10816-21 in preparation. The author of the article Dr. Edwin Becker is the nominated expert for Germany.

• 한국사회복지학
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• 제60권3호
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• pp.275-297
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• 2008

본 연구의 목적은 중 고령자의 경제적 노후 준비와 그 결정 요인을 분석하고, 이를 바탕으로 정책적 함의를 도출하는 데 있다. 분석자료는 통계청의 2007년 사회통계조사자료로서 이 조사에 포함되어 있는 45세에서 59세 사이의 중 고령자 18,354명을 분석대상으로 삼았다. 연구의 개념체계는 Andersen 모형에 기반했으며, 경제적 노후준비에 미치는 요인을 logistic 분석을 이용하여 찾고자 하였다. 분석결과는 다음과 같다. 첫째, 경제적 노후준비가 전혀 안된 중 고령자의 비율이 상당히 높고, 나이가 들수록 오히려 경제적 노후준비를 하지 않은 비율은 높다. 둘째, 남성, 교육수준, 결혼상태, 경제활동, 현재소득인식, 주택소유, 거주지역, 전반적 생활여건은 경제적 노후준비에 긍정적인 영향을 미친다. 셋째, 남성, 연령, 경제활동은 사적 경제적 노후준비에 부정적인 영향을 미치지만, 교육수준, 현재소득인식, 전반적 생활여건향상은 사적 경제적 노후준비에 긍정적인 영향을 미친다. 넷째, 남성, 교육수준, 결혼상태, 경제활동, 현재소득인식, 주택소유, 거주지역, 전반적 생활여건향상, 장래소득기대는 부수적 경제적 노후준비에 긍정적 영향을 미치고, 연령은 부수적 경제적 노후준비에 부정적 영향을 미친다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2000년도 춘계학술대회 논문집
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• pp.164-171
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• 2000

To determine operational requirement, the environmental condition for an equipment must be investigated, and to certify equipment's normalized operation, appropriate test must be carried out under the considered environmental condition. The actual environmental conditions to which equipment is likely to be exposed are normally complex and will comprise a number of environmental factors and corresponding parameters, When defining the environmental conditions for a certain application it is, therefore, necessary to list the factors involved and select the appropriate severity. For the preparation to determine operational requirement, environmental condition of equipment is investigated. The environmental condition is structured in two separate such as requirements, guidance and test specifications. For the first step, environmental requirements are considered

• 대한가정학회지
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• 제25권2호
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• pp.79-87
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• 1987

Paeksolgi is a typical Korean rice cake made by steaming rice powder added sugar, water and salt. This study attempted to clarify the factors which affect the textural characteristics, and to examine the effects of various steaming time and volume of adding water on sensory characteristics and Instron measurement on textures of Paeksolgi. Evaluation was conducted through sensory evaluation and objective evaluation. The results were summarized as follows. 1. In the preparation, the significant factors were soaking time, volume of sugar, and the interaction between soaking time and volume of adding water. And, Kind of sweetener, volume of adding water, steaming time, condition of powder, and the interaction between soaking time and steaming time, and between soaking time and volume of adding water, and between kind of sweetener and condition of powder, and between steaming time and volume of sugar were the significant factors which affected the textural characteristics of Paeksolgi. 2. In sensory evaluation on the various steaming time and volume of adding water, Paeksolgi made by steaming rice powder added water of 10% for 30 min. showed the most favorite tendency on the overall quality. The results of Instron measurement indicated that hardness, gumminess and chewiness tended to decrease as volume of adding water increased in same steaming time.

• Restorative Dentistry and Endodontics
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• 제19권1호
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• pp.97-105
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• 1994

The purpose of this study was to evaluate the smear layer removing efficiency of two root canal preparation techniques. Twelve single-rooted teeth were used in two groups of six each. Group 1 was biomechanically prepared by hand using a K-file with a high volume of normal saline irrigation. Group 2 was. prepared by using ultrasonically activated K-file with a constant high volume of normal saline irrigation. After the experimental procedures, each root was split saggitally. The removing efficiency of the preparation methods were assessed in terms of surface condition of the canal walls at three levels, those coronal, middle, and apical thirds. On the basis of remaining debris, presence of smear layer, and patency of dentinal tubules, each canal was evaluated according to a scale form 0 to 2. A statistical analysis was used to indicated any significant differences in surface condition between the two methods. There was no statistical significance between hand instrumentation and ultrasonic instrumentation at the cervical third but removing efficiency of ultrasonic instrumentation was superior. No statistically significant differences were obhserved for middle or apical third.