• 한국항해항만학회지
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• 제31권5호
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• pp.403-408
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• 2007

본 논문에서는 Jahanshahloo et al (2007)가 새롭게 제시한 모형을 이용하여 2004년도, 국내 26개 항만들을 대상으로 2개의 투입변수(접안능력, 하역능력)와 3개의 산출변수(수출화물처리량, 수입화물처리량, 입출항척수) 가 있는 경우의 CCR[Charnes, Cooper, Rhodes(l978)] 효율성을 측정하였다. 또한 효율성이 1인 효율적인 항만들을 제거하는 방법과 나머지 항만들의 효율성을 평균하는 방법을 이용하여 효율적인 항만들의 정확한 순위를 측정하였다. 실증분석의 핵심적인 결과를 살펴보면, 가장 효율적인 항만의 순위는 옥포, 삼척, 울산, 대산, 부산, 고현항의 순위로 나타났다. 10개의 컨테이너항만을 제외한 16개 일반 항만들 중에서는 삼척항이 가장 강력한 효율적인 항만으로 나타났다. 정책적인 함의는 항만정책당국이 본 논문에서 사용한 분석방법과 더 장기적인 기간을 대상으로 효율성 분석을 시행하고 효율적으로 판명된 항만들에 대해서는 정확한 순위를 파악하고 그러한 결과를 차후 항만투자와 개발 시에 반드시 고려하고 반영해야만 한다는 점이다.

• 대한치과기공학회지
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• 제41권3호
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• pp.211-217
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• 2019

Purpose: The purpose of this study is to evaluate the repeated measurement stability of scans related to dentition type. Methods: A normal model and the crowding and diastema models are also duplicated using duplicating silicon. After that, a plaster model is made using a plaster-type plaster on the duplicate mold, and each model is scanned 5 times by using an extraoral scanner. The gingival part and molar part were deleted from the 3D STL file data obtained through scanning. Using the 3D stl file obtained in this way, data is nested between model groups. Thereafter, RMS values obtained were compared and evaluated. The normality test of the data was performed for the statistical application of repeated measurements with dentition type, and the normality was satisfied. Therefore, the one-way ANOVA test, which is a parametric statistical method, was applied, and post-tests were processed by the Scheffe method. Results: The average size of each RMS in the Normal, Diastema, and Crowding groups was Normal> Crowding> Diastema. However, the standard deviation was in the order of Crowding> Normal> Diastema. The average value of each data is as follows. Diastema model was the smallest ($5.51{\pm}0.55{\mu}m$), followed by the crowding model ($12.30{\pm}2.50{\mu}m$). The normal model showed the maximum error ($13.23{\pm}1.06{\mu}m$). Conclusion: There was a statistically significant difference in the repeatability of the scanning measurements according to the dentition type. Therefore, you should be more careful when scanning the normal intense or crowded dentition than scanning the interdental lining. However, this error value was within the range of applicable errors for all clinical cases.

• The Korean Journal of Pain
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• 제30권4호
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• pp.243-249
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• 2017

Pain is subjective, while statistics related to pain research are objective. This review was written to help researchers involved in pain research make statistical decisions. The main issues are related with the level of scales that are often used in pain research, the choice of statistical methods between parametric or nonparametric statistics, and problems which arise from repeated measurements. In the field of pain research, parametric statistics used to be applied in an erroneous way. This is closely related with the scales of data and repeated measurements. The level of scales includes nominal, ordinal, interval, and ratio scales. The level of scales affects the choice of statistics between parametric or non-parametric methods. In the field of pain research, the most frequently used pain assessment scale is the ordinal scale, which would include the visual analogue scale (VAS). There used to be another view, however, which considered the VAS to be an interval or ratio scale, so that the usage of parametric statistics would be accepted practically in some cases. Repeated measurements of the same subjects always complicates statistics. It means that measurements inevitably have correlations between each other, and would preclude the application of one-way ANOVA in which independence between the measurements is necessary. Repeated measures of ANOVA (RMANOVA), however, would permit the comparison between the correlated measurements as long as the condition of sphericity assumption is satisfied. Conclusively, parametric statistical methods should be used only when the assumptions of parametric statistics, such as normality and sphericity, are established.

• East Asian mathematical journal
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• 제28권2호
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• pp.109-133
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• 2012

In this research, I selected a Singapore elementary mathematics textbook which substantially reflects Singapore curriculum, and compared it with Korean one to understand how they differ in the contents system of the curriculum focused on the contents of the geometry and measurement strand, and analyzed their common points and different points intensively with textbooks for sixth-grade students. Also, I translated a chapter of the textbook, 'Mathematics in Action'. That chapter was about circumference and the area of the circle which is related to the shapes part. Then, I taught it to the experimental group to compare their achievement and the change of reaction to studying the shape-related parts with those of the control group. The results are the followings. First, when we analyze the contents of shape-related part of the textbooks for sixth-grade students of both countries, Singaporean textbook contains more contents that are introduced for the first time, which implies that it is more desirable to teach new concepts of shapes when students are in their higher grades. Second, as for the way they develop the activity of each chapter, Korean textbook sticks to a uniform way, while the Singapore textbook uses various ways for different subjects and grades. In addition, when they organize the contents of the textbook, they emphasize the importance of student's activity and lead students with various methods by suggesting several questions and situations.

• 한국소음진동공학회논문집
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• 제19권4호
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• pp.347-354
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• 2009

Frequency analysis is one of the most useful way to analyze response signal for the purpose of grasping the dynamic characteristics of system through Fourier transformation. Although it is very effective way for frequency analysis, it is hard to analyze out a specific sound or vibration component which is correlated with others. In this thesis, source contribution analysis tool for NI-PXI equipment is developed with LabVIEW using coherences of MISO(multiple-input single-output) model. For the purpose of examining propriety of developed tool, simulation is performed with several correlated signals that have different frequency range. After checking the OCF(ordinary coherence function) and PCF(partial coherence function) of the each signal for concerned frequency domain, an experiment is conducted on an evaporator that cause the principal noise of a refrigerator. This developed tool will be expected to build up more convenient and serviceable measurement system.

• Smart Structures and Systems
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• 제15권5호
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• pp.1363-1372
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• 2015

Smart structures and intelligent systems play pivotal roles in numerous areas of applied sciences ranging from civil engineering to computer and communications systems engineering. Although such structures and systems have been intensively deployed in these areas, they have been, interestingly, very rarely deployed in the field of cultural heritage preservation.This paper presents one of thefirst such attempts. A new methodology is describedthat deploys smart structures andlinks them with artificial intelligence methods.These solutions are referred toas advanced hybrid engineering artefacts. By their use,important environmental factors can be monitoredin hard to access, remote or unsafe locationsby minimizing the need for human involvement. In addition toproviding safety the methodologyalso reduces costs and, most importantly,providesa new way to modelany particular micro-environment in a much more efficient way than this is possible with traditional ways. Last but not least, although themethodology has been developed for cultural heritage preservation, its application areas are much broader and it is expected that it will find its applicationin other domains like civil engineering and ecology.

• 공학교육연구
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• 제23권5호
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• pp.51-60
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• 2020

The purpose of this study is to develop and validate an Engineering Empathy Instrument. Engineering empathy is defined as the ability that encompasses the following three qualities, a skill to interpret social issues and phenomenon that may occur in the process of interactions between human beings and engineering systems, a practical orientation that enables one to take stakeholders' perspectives to carry out an engineering project, and a professional way of being that acknowledges empathic skills and associated practice orientations. Based on this notion, we develop a scale to measure engineering empathy and have surveyed 429 engineering students. Evidence for the validity and reliability of the scale is presented. In conclusion, we find that engineering empathy can be measured and conceptualized as three domains: a Learnable Skill (ELS), a Practical Orientation (EPO), and a Professional Way (EPW). We also find that sophomores show the highest level of engineering empathy as compared with other graders. While students accumulate technical knowledge, their understanding about engineering in social and interpretational contexts gets weakened. This implies that engineering education necessarily emphasizes the impacts of engineering solutions in interpersonal, societal, technologies, and environmental contexts.

• 한국산업정보학회논문지
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• 제16권3호
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• pp.57-63
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• 2011

인터넷의 개방성과 정보공유 및 교환의 용이성으로 인해 해킹사건은 발생 빈도수가 높아지고 있으며, 해킹유형 또한 고도화 복잡화되고 있다. 그리고 그 피해규모와 심각성은 측정이 불가능하다. 패스워드 보안은 인터넷에서 자신과 정보를 보호하기 위한 필수적인 도구이며, 이것은 아무리 강조해도 지나치지 않는다. 패스워드는 암호화할 경우 7글자 이상으로 구성하면 충분하다. 본 논문에서는 가상키보드들 통해 패스원드를 입력하며, 아이디의 일부정보와 최종 접근 승인시간을 기반으로 하는 개선된 1회용 패스워드 변경기법을 적용하는 확장 알고리즘을 제안한다.

• 가정과삶의질연구
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• 제28권4호
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• pp.67-76
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• 2010

This study investigates working parent stress. This study surveyed 240 working mothers who are raising toddlers and 106 teachers in Seoul, Cyeong-gi, and Incheon. For this study, the Parenting Stress scale developed by Kim & Kang (1997) was used as the instruments for measurement and parental stress. To measure maternal separation anxiety, this study used the Maternal Separation Anxiety Scale (MSAS) developed by Hock (1989), while the Attitude for Occupation scale developed by Farel (1980) was used to measure the attitude for occupation. In addition, the Preschool Adjustment Questionnaire (PAQ) developed by Jewsuwan, Luster and Kostelink (1992), and modified by Oh Chong Eun (2001) were used as the instruments for measurement and adjustment. Data analysis was done using the SPSS WIN 15.0 version and the collected data were subject to a descriptive statistical analysis, one-way ANOVA t-test, and multiple regression analysis. The influential independent variables affecting parenting stress listed in order of significance were maternal attitude for occupation, adjustment of children, maternal anxiety, and income.

• 복식
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• 제10권
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• pp.51-62
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• 1986

The purpose of this study was to investigate the relationships among Clothing Satisfaction, Social approval, Psychological dependence, and Social security-insecurity and to determine the difference of clothing behaviors by the demographic variables such as age, socioeconomics status, education, religion, and material status. Clothing Satisfaction was measured by Rim's Questionnaire(1974) moditide and supplemented for this study. For the measurement of Social approval and Psychological dependence, the Clothing Interest Inventory developed by Creekmore (1971) was adapted for this story. The measurement for the Social security-insecurity was adapted from Lapitsky's (1961) Social Security Inventory. Data were collected from 322 purposively selected elderly women over sixty dwelling in Seoul by means of interviews. For statistical analysis, frequency distribution, one-way analysis of variance, Pearson's correlation coefficients were used. The results were as follows: 1. There were significant relationships among Clothing satisfaction, Social approval, and Psychological dependence. Negative significant relaionships were found between Clothing satisfaction and Social approval and between Clothing satisfaction and Psychological dependence. 2. There was negative significant relationship between Social security-insecurity and Clothing satisfaction, while positive significant relationships were found between Social security-insecurity and Social approval, and between Social security- insecurity and Psychological dependence. 3. There was significant difference in Clothing satisfaction according to socioeconomic status and education. 4. There was significant difference in Social approval according to socioeconomic statusand education. 5. There was significant difference in Psychological dependence according to education and religion.