• Environmental Engineering Research
• /
• 제24권2호
• /
• pp.347-353
• /
• 2019

Although membrane distillation (MD) has great promise for desalination of saline water sources, it is crucial to improve its thermal efficiency to reduce the operating cost. Accordingly, this study intended to examine the thermal energy efficiency of MD modules in a pilot scale system. Two different modules of hollow fiber membranes were compared in direct contact MD mode. One of them was made of polypropylene with the effective membrane area of $2.6m^2$ and the other was made of polyvinylidene fluoride with the effective membrane area of $7.6m^2$. The influence of operation parameters, including the temperatures of feed and distillate, feed flow rate, and distillate flow rate on the flux, recovery, and performance ratio (PR), was investigated. Results showed that the two MD membranes showed different flux and PR values even under similar conditions. Moreover, both flow rate and temperature difference between feed and distillate significantly affect the PR values. These results suggest that the operating conditions for MD should be determined by considering the module properties.

• KSBB Journal
• /
• 제15권4호
• /
• pp.337-341
• /
• 2000

The decanter is very useful to harvest biomass from plant cell cultures in large-scale process. It is very important to obtain high yield and low moisture content in recovered biomass so as to minimize solvent usage in subsequent extraction steps. Effluent clarity was also affected by the differential speed although this affect was more dramatic at higher flow rates than at lower flow rates. Moisure content was largely unaffected by flow rate. A decrease in moisture content was evident as differential speed decreased.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2011년도 춘계학술대회 논문집
• /
• pp.308-314
• /
• 2011

The research which sees, the parameters inputs and acoustic measurement result in simulation error most on a large scale concreteness of 3D models which affect number of effective surface. Therefore DATA of above the comparison which will listen, analyzed and investigated.

• 한국정보처리학회:학술대회논문집
• /
• 한국정보처리학회 2018년도 추계학술발표대회
• /
• pp.313-316
• /
• 2018

In this paper, the authors reflect on how a lecturer's cross-cultural gestures affect learners from across cultures online and in the field teaching sessions for improving the service when to build an e-Learning system. The study extends to survey the way learners feel about cultural differences during a presentation from the research based on sociolinguistics research. Before starting a full-scale research, a preliminary study has been conducted to base the initial experiment, and analysis these result for main research.

• 한국사회복지학
• /
• 제58권3호
• /
• pp.27-49
• /
• 2006

본 연구는 구조적 차원성 탐색을 통한 최성재의 '노인 생활 만족도 척도'의 재검증을 목적으로 한다. 이를 위해 충주지역에 거주하는 65세 이상 노인 275명의 자료가 분석되었다. 연구 결과 '노인 생활 만족도 척도'는 세 개의 이론적 구인으로 구성된 다차원 구조를 갖는 것으로 분석되었다. 규명된 구인은 '긍정적 정서와 주관적 만족감', '부정적 자아상과 부정적 정서', 그리고 '자기 가치'로 명명되었다. 세 구인 모두 높은 신뢰도를 보였으며 '내적 구조에 근거한 타당도' 또한 모두 높은 것으로 분석되었다. '긍정적 정서와 주관적 만족감' 그리고 '부정적 자아상과 부정적 정서'는 수렴 타당도와 판별 타당도가 모두 높은 것으로 나타났다. '자기 가치'는 높은 수렴 타당도를 보인 반면 판별 타당도는 상대적으로 낮은 것으로 나타났다. 본 연구의 결과는 '노인 생활 만족도 척도'를 단일 차원 구조로 제시한 개발자의 견해와 달리 '노인생활 만족도 척도'의 다차원 구조를 검증함으로써 다수의 선행 연구 결과를 지지한다. 끝으로 '노인 생활 만족도 척도'의 구조적 차원성이 개발자의 연구와 본 연구에서 상이하게 나타난 원인이 논의되었다.

• Asian Pacific Journal of Cancer Prevention
• /
• 제14권4호
• /
• pp.2615-2619
• /
• 2013

Background: The aim of this study was to examine the effects of perceived parental attitudes on children's discernment of cigarettes. Materials and Methods: The study sample consisted of 250 children attending grades 6, 7 and 8. Data were collected via a socio-demographic survey questionnaire, the Parental Attitude Scale (PAS) and the Decisional Balance Scale (DBS). Data analysis covered percentages, medians, one-way analysis of variance (ANOVA) and post-hoc tests using a statistical package. Results: There were 250 participants; 117 were male, 133 were female. The mean age was $13.1{\pm}0.98$ for the females and $13.3{\pm}0.88$ for the males. A statistically significant difference was found in the children's mean scores for 'pros' subscale on the Decisional Balance Scale (DBS) according to perceived parental attitudes (F=3.172, p=0.025). There were no statistically significant differences in the DBS 'cons' subscale scores by perceived parental attitudes. Conclusions: It was determined that while perceived parental attitudes affect children's views on advantages of smoking, they have no effect on children's views on its disadvantages.

• 한국지능시스템학회논문지
• /
• 제25권1호
• /
• pp.15-21
• /
• 2015

커널에 대한 모수의 조절은 서포트 벡터 기계의 일반화 능력에 영향을 준다. 이와 같이 모수들의 적절한 값을 결정하는 것은 종종 어려운 작업이 된다. 서포트 벡터 회귀에서 이와 같은 모수들의 값을 결정하기 위한 부담은 앙상블 학습을 사용함으로써 감소시킬 수 있다. 그러나 대용량의 자료에 대한 문제에 직접적으로 적용하기에는 일반적으로 시간 소모적인 방법이다. 본 논문에서 서포트 벡터 회귀의 모수 조절에 대한 부담을 감소하기 위하여 원래 자료집합을 유한개의 부분집합으로 분해하는 방법을 제안하였다. 제안하는 방법은 대용량의 자료들인 경우와 특히 불균등 자료 집합에서 효율적임을 보일 것이다.

• 한국직업건강간호학회지
• /
• 제7권2호
• /
• pp.155-163
• /
• 1998

In order to investigate the effects of rotating shift work on the subjective characteristics of sleep and mental depression questionnaire survey was carried out on 405 shift workers and 153 nonshift workers who were nurses employed. in three university hospital. The questionnaire forms used in this study were the self rating depression scale(SDS) and circadian type questionnaire(CTQ) factor R(rigidity/flexbility of sleeping habit) and factor V(inability/ability to overcome drowsiness). The results were as follows ; 1. Mean score of CTQ R in shift workers was significantly lower than that in nonshift workers, however, no significant difference in CTQ V was observed between two groups. 2. Mean score of SDS was significantly higher in shift workers(44.1) than in nonshift workers(39.8). 3. Mean self rating depression scale scores of pervasive affect, physiologic equivalents and psychological equivalents were significantly higher in shift workers than in nonshift workers. 4. In shift worker, mean SDS score was the highest in confusion and followed by diurnal variation, retardation, and indeciveness in the descending order. In nonshift worker, that score was the highest in decreased libido and followed by confusion, and indeciveness in the descending order. 5. Circadian type questionnaire scores was significantly and negatively correlated with significantly and negatively correlating with Self-rating depression scale scores(r=-0.473).

• Wind and Structures
• /
• 제20권6호
• /
• pp.719-737
• /
• 2015

Full scale measurement on the structural dynamic characteristics and Vortex-induced Vibrations (VIV) of a long-span suspension bridge with a central span of 1650 m were conducted. Different Finite Element (FE) modeling principles for the separated twin-box girder were compared and evaluated with the field vibration test results, and the double-spine model was determined to be the best simulation model, but certain modification still needs to be made which will affect the basic modeling parameters and the dynamic response prediction values of corresponding wind tunnel tests. Based on the FE modal analysis results, small-scaled and large-scaled sectional model tests were both carried out to investigate the VIV responses, and probable Reynolds Number effects or scale effect on VIV responses were presented. Based on the observed VIV modes in the field measurement, the VIV results obtained from sectional model tests were converted into those of the three-dimensional (3D) full-scale bridge and subsequently compared with field measurement results. It is indicated that the large-scaled sectional model test can probably provide a reasonable and effective prediction on VIV response.

• 동의신경정신과학회지
• /
• 제6권1호
• /
• pp.71-84
• /
• 1995

This paper is for studying interrelation between Stress perception, Todai Index(THI) test and coffee. this study was done on 163 college women whose ages were 18 to 33 and who were in University in Wonju. The Stress perception test and THI test shows the following results. 1. The Stress test on the group that drunk coffee and beverage shows high degree of oppression sense about school and daily life. 2.The total THI test on the group that drunk coffee shows high degree of complaint on mouth, evacuation and lie scale, but shows the lowest piont on nervousrness. 3. The D-group womrn who drink a cup of coffee, two or three show the highest complaint on mouth and evacuation. E-group shows the lowest lie scale. 4 The Stress test and health examination on the group that drunk coffee show high degee of stress. And it also shows stimulative relation between the condition of body health and drinking coffee. The above shows that coffee and some beverage can affect on mental and physical health. Especially they are considered as a factor of stimulus on stress response. Through the THI test, the effect on mouth and evacuation, lie scale and nervousness could be obseved. So the drinking coffee and beverage requires circumspection.