• 설비공학논문집
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• 제10권6호
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• pp.743-752
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• 1998

Experiments were performed to characterize single-phase heat transfer behavior of submerged liquid jet with multiple nozzle normally impinging on the smooth and extended surfaces. Arrays of 9 and 36 nozzles were used, with diameters of 0.5 to 2.0mm providing nozzle area ratio (AR) from 0.05 to 0.2. The square pin fin arrays were chosen as extended surfaces and the effects of geometrical parameters such as fin height, the ratio of fin width to channel width on heat transfer enhancement were examined. Single nozzle characteristics were also evaluated for comparison. The results clearly showed that heat transfer enhancement could be realized by using multiple nozzles at the constant volume flow rate. The average Nusselt number of multiple nozzle impingement on the smooth surface was correlated by the following equation : Nu/$Pr\frac{1}{3}=0.94 Re^{0.56}N^{-0.12}AR^{0.50}$The average heat transfer coefficients of multiple nozzle impingement on the extended surfaces decreased with increasing fin height and the ratio of fin width to channel width. The effectiveness of ex-tended surfaces ranged from 1.5 to 3.5 depending on the fin height, the ratio of fin width to channel width of pin fin arrays, nozzle number and nozzle area ratio.

• 기본간호학회지
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• 제21권4호
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• pp.433-445
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• 2014

Purpose: This study was conducted to examine relationships between critical thinking disposition and multiple intelligences. Method: Participants were nursing students (N=186) who completed a questionnaire assessing critical thinking disposition and multiple intelligences. Data were analyzed using descriptive statistics, t-test, analysis of variance with post hoc comparison, and Pearson correlation coefficients. Results: For type of multiple intelligences, 32.9% of students had the strongest fit for "interpersonal intelligence" type and 20.1% for "intrapersonal intelligence" type. Mean score for critical thinking disposition was $3.42{\pm}0.37$. Factors related to critical thinking disposition were participation in club activities (F=5.962, p=.001) with a representative role in the club (t=2.140, p=.034). There were significant differences in interpersonal intelligence scores by personality traits (t=2.445, p=.015), participation in club activities (F=10.003, p<.001), and friendship (t=2.539, p=.012); and significant differences in intrapersonal intelligence scores by participation in club activities (F=3.862, p=.010), having a representative role in the club (t=2.101, p=.037), and friendship (t=2.220, p=.029). Conclusion: Results indicate that critical thinking disposition is significantly associated with multiple intelligences and suggest that multiple intelligences should be considered to enhance critical thinking disposition when tailored teaching is adopted in nursing education.

• 한국지능시스템학회논문지
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• 제24권5호
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• pp.529-535
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• 2014

본 논문에서는 interval type-2 possibilistic fuzzy C-means(IT2PFCM) 클러스터링 방법에 multiple Gaussian kernels을 기반으로 한 possibilistic fuzzy C-means multiple kernels(PFCM-MK) 알고리즘을 결합하여 적응적인 하이브리드 클러스터링 방법인 multiple kernels interval type-2 possibilistic fuzzy C-means(IT2PFCM-MK) 방법을 제안 하였다. 일반적으로 possibilistic fuzzy C-means(PFCM) 알고리즘은 fuzzy C-means(FCM) 알고리즘의 단점인 노이즈 민감성 및 특이점 문제와 알고리즘 초기 클러스터의 Prototype에 따라 위치가 겹치는 문제를 해결하기 위해 제안 되었다. 하지만 이 방법 역시 퍼지화 파라미터 값에 따라 위와 같은 문제를 여전히 가지고 있기 때문에 이와 같은 문제를 보완하기 위해 interval type-2 퍼지 접근 방법을 이용 하는 interval type-2 possibilistic fuzzy C-means(IT2PFCM) 알고리즘을 제안 하였다. 또한 multiple kernels 함수를 interval type-2 possibilistic fuzzy C-means(IT2PFCM) 알고리즘에 적용하여 분류하기 복잡한 형태의 데이터와 노이즈가 있는 데이터에 대하여 보다 정확하고, 향상된 클러스터링을 수행할 수 있다.

• Journal of Mechanical Science and Technology
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• 제18권12호
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• pp.2182-2189
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• 2004

In the recent years, environmentally conscious design and manufacturing technologies have attracted considerable attention. The coolants, lubricants, solvents, metallic chips and discarded tools from manufacturing operations will harm our environment and the earth's ecosystem. In the present work, the Tukey method of multiple comparisons is used to select the minimum level of coolant required in a turning process. The amount of coolant is varied in 270 designed experiments and the parameters cutting temperature, surface roughness, and specific cutting energy are carefully evaluated. The effects of coolant mix ratio as well as the amount of coolant on the turning process are studied in the present work. The cutting temperature and surface roughness for different quantity of coolant are investigated by analysis of variance (ANOVA) - test and a multiple comparison method. ANOVA-test results signify that the average tool temperature and surface roughness depend on the amount of coolant. Based on Tukey's Honestly Significant Difference (HSD) method, one of the multiple comparison methods, the minimum level of coolant is 1.0 L/min with 2% mix ratio in the aspect of controlling tool temperature. F-test concludes that the amount of coolant used does not have any significant effect on specific cutting energy. Finally, Tukey method ascertains that 0.5 L/min with 6% mix ratio is the minimum level of coolant required in turning process without any serious degradation of the surface finish. Considering all aspects of cutting, the minimum coolant required is 1.0 L/min with 6% mix ratio. It is merely half the coolant currently used i.e. 2.0 L/min with 10% mix ratio. Minimal use of coolant not only economically desirable for reducing manufacturing cost but also it imparts fewer hazards to human health. Also, sparing use of coolant will eventually transform the turning process into a more environment-conscious manufacturing process.

• 복식문화연구
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• 제31권3호
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• pp.361-378
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• 2023

This research not only determined the preference of fashion brand distribution channels of active Korean and Chinese seniors who became major consumers in the fashion industry, but also analyzed the effect on these preferences and choices of distribution channels depending on personal consumption characteristics and differences between the two groups. Data was collected by a professional survey firm. SPSS 24.0 and AMOS 24.0 were used for empirical analysis, and frequency analysis, multiple response analysis, EFA, reliability analysis, CFA, SEM, and multiple-group comparison analysis were performed. As a result of multiple response analysis, the offline channel was revealed as the preferred fashion distribution channel for active Korean and Chinese seniors; the second most popular was the online channel. The results of multiple-group comparison analysis reveal differences between two groups in seeking emotional consumption via the offline channel; the effect was only evident for active Korean seniors. A difference in seeking emotional consumption via preference for online channel also existed, but only for active Chinese seniors. For these reasons, marketers targeting active Korean seniors will be effective to not only offer brand information by fashion display to let seniors understand the fashion brand, but also to have brand events to form positive emotions toward the fashion brand. Moreover, targeting active Chinese seniors will be necessary to transmit brand sensibility by utilizing metaverse marketing comprising various factors, so that consumers can enjoy the fashion brand.

• 가정과삶의질연구
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• 제26권4호
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• pp.73-83
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• 2008

This study examines the effects of mass media, the tendency for young women to make body comparisons, and the BMI of female high school and college students on their attitudes about eating. Participants were 392 high school students from Gyeonggi Province and 391 college students from Seoul, Gyeonggi and Chung-nam Province. Collected data were analyzed through Cronbach's ${\alpha}$, t-test, One-way ANOVA, $Scheff{\acute{e}}$ test, Pearson's correlation, and stepwise multiple regression. The findings of the study were as follows: 1) While mass media influence differed by grade, tendency for appearance comparison and attitude toward eating did not differ by grade. 2) Mass media influence, tendency for appearance comparison and attitude toward eating differed by BMI. 3) Mass media pressure, specific attributes comparison, and BMI were significant predictors of attitudes toward eating. 4) Tendency for appearance comparison played a mediating role in the relationship between mass media and attitudes toward eating.

• 한국항행학회논문지
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• 제1권1호
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• pp.35-46
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• 1997

다중 표적의 추적은 과거 10여년 동안 레이다 용용분야에서 큰 주목을 받아 왔으며 많은 학술회의와 논문발표의 중심 과제가 되어왔다. 이 문제를 해결하기 위하여 여러 가지 추적방식들이 제시되어 왔다. 그 중 대표적인 것으로는 Nearest Neighbor (NN) 방식에 의한 비확률적인 짝배정(association) 방법과 확률적인 표적모형에 기초한 Multiple Hypothesis Test (MHT) 방식 및 Joint Probabilistic Data Association (JPDA) 방식으로 대별할 수 있다. 이러한 여러 가지 방식들은 각기 그 장점 및 단점을 가지게 되어 계산속도나 표적의 추적정확도에 있어서 큰 차이를 나타내게 된다. 본 논문에서는 NN방식, MHT 방식 및 JPDA 필터에 기초한 세 가지 추적 알고리듬을 비교하고, 시뮬레이션을 통하여 다중 기동 표적에 대하여 그 추적성능을 분석한다.

• 한국생활과학회지
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• 제15권1호
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• pp.71-81
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• 2006

The purpose of this study is to examine the differences in young children's multiple intelligence and social behaviors based not only on Montessori and general programs of day care centers but also on their gender and social- demographic factors. The subjects were 329 young children (182 boys and 147 girls aged from four to five) from two day care centers in Cheongju city. The instruments used in this study were HAPI (Hillside assessment of Perceived Intelligence) to measure the surveyee's multiple intelligence and Park & Lee's scale to measure their social behaviors. The frequencies, percentiles, mean, standard deviations, Cronbach a, t-teat, F and LSD were used to analyze the collected data through SPSS WIN program. The results of this study are as follows: 1) As for young children's multiple intelligence, there are differences according to young children's gender, order of birth, parents' level of education and teacher's working period out of social-demographic factors. 2) As for the young children's social behavior, there are differences according to young children's gender, mother's level of education and teacher's working period out of social-demographic factors.

• 한국정보통신학회논문지
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• 제9권6호
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• pp.1174-1181
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• 2005

대량의 데이터를 빠르게 전송할 수 있는 UWB(Ultra-widebandwidth) 시간 도약(time hopping : TH) 펄스 위치 변조(pulse position modulation : PPM) 다중 통신 시스템의 비트 오율을 정확히 계산할 수 있는 방법을 소개한다. 본 논문에서 다중 접근 간섭(multiple access interference : MAI)의 통계적 성질을 특성함수 기법을 이용하여 정확히 모델링 하였고 이를 바탕으로 TH-PPM 시스템의 비트 오율을 정확하게 계산할 수 있는 해석 식을 제시하였다. 또한, 기존의 MAI에 대한 가우시안 근사에 비하여 상당히 개선된 정확성을 갖는 근사식을 함께 소개하였다. 본 논문에서 제시한 모델에 의해서 계산된 비트 오율을 Monte-Carlo 시뮬레이션 한 결과와 비교함으로써 제안한 BER 식의 정확성 및 타당성을 검증하였다.

• 자원ㆍ환경경제연구
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• 제19권1호
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• pp.23-43
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• 2010

본 연구는 탄소배출권거래시 할당과 관련한 방법론 중 경매할당에 관한 연구로, 실험경제 방식을 이용하여, 가격결정방식간의 효율성을 비교하였다. 가격결정방식 중 단일가격 결정방식과 복수가격 결정방식에 대한 효율성을 비교하기에 앞서 무상할당, 일률배분 할당, 경매할당에 대한 배출권 가격분포를 분석함으로써, 경매할당이 불완전경쟁 체제하에서 시장수렴면에서 우월함을 입증하였다. Buckley et al.(2004) 연구에서 적용한 실험방식을 활용하여 거래상황을 설계하였으며, 실험결과, 단일가격 결정방식이 효율성 면에서 우월한 것으로 나타났다. 특히, 단일가격 결정방식은 시장참여자들이 승자의 저주(winner's curse)를 회피할 수 있기 때문에 시장참여자들이 보다 과감하게 입찰에 응함으로써, 배출권거래 운영자에게 한계저감비용에 대한 정보를 쉽게 노출시킨다는 점에서 거래운영을 용이하게 하는 이점이 있는 것으로 나타났다. 그러나, 경매수익 면에서는 단일가격 결정방식이 복수가격 결정방식보다 우월하다는 결론을 내리기에는 통계적 유의성이 확보되지 않았다.