• Environmental Engineering Research
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• 제15권3호
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• pp.129-134
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• 2010

The optimization of experimental parameters, such as catalyst type, catalyst concentration, molar ratio of alcohol to oil and reaction temperature, on the transesterification for the production of rapeseed methyl ester has been studied. The Taguchi approach (Taguchi method) was adopted as the experimental design methodology, which was adequate for understanding the effects of the control parameters and to optimize the experimental conditions from a limited number of experiments. The optimal experimental conditions obtained from this study were potassium hydroxide as the catalyst, at a concentration of 1.5 wt %, and a reaction temperature of $60^{\circ}C$. According to Taguchi method, the catalyst concentration played the most important role in the yield of rapeseed methyl ester. Finally, the yield of rapeseed methyl ester was improved to 96.7% with the by optimal conditions of the control parameters which were obtained by Taguchi method.

• 한국해양공학회지
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• 제33권4호
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• pp.358-363
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• 2019

The acoustic power is used as a primary index characterizing underwater sound sources and could be defined by its source level. The source level has been assessed using various experimental techniques such as the reverberation time method and reverberant tank plot method. While the reverberation time method requires reverberation time data extracted in a preliminary experiment in a reverberant water tank, the reverberant tank plot method only needs acoustic pressure data directly obtained at the reverberation water tank. In this research, these experimental techniques were studied in comparative experiments to estimate the source levels of underwater sources in a reverberant water tank. This paper summarizes the basic theories and procedures of these experimental techniques and presents the experimental results for an underwater source in a long cuboid water tank using each technique, along with a discussion.

• 한국식품영양학회지
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• 제23권4호
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• pp.607-614
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• 2010

The aim of this study was to investigate the quality characteristics of sponge cakes with added rice flour produced by a modified genoise method to prevent volume reduction. A control group and experimental group I were prepared by the genoise method and experimental groups II, III, and IV were produced by a modified genoise method in which they were mixed with wheat flour and water to a make paste to form gluten for 3, 6, and 9 minutes, respectively. One third of the wheat flour in all experimental groups was replaced by rice flour. The control and experimental groups were compared in terms of quality characteristics, including batter specific gravity, volume, color, textural characteristics, and sensory qualities, to determine the optimal pasting time for wheat flour in the formulation. The specific gravity of the experimental groups was higher than that of the control and decreased with increasing wheat flour pasting time. The volume of experimental group I was lower than that of the control group, and the volume values of experimental groups III and IV, made by the modified genoise method, were higher than that of the control group. $dL^*$ and $db^*$values for the crust and inside of the cake were lower in the experimental groups than in the control. The $dL^*$ value, indicating brightness, increased as pasting time increased. The hardness values of experimental groups I and IV were higher than that of the control whereas experimental groups II and III had lower hardness values. Chewiness was higher in the control group, as well as experimental groups I and IV than in the experimental groups II and III. The gumminess of experimental group IV was highest. Cohesiveness decreased by adding rice flour to the sponge cake. Sensory attributes of cell uniformity, tenderness, moistness, taste, and overall acceptability had the highest scores in experimental group III. Based on these results, we conclude that the quality of sponge cake containing one third of the wheat flour replaced by rice flour is best with 6 minutes pasting of the wheat flour to form gluten.

• 한국간호교육학회지
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• 제5권1호
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• pp.86-96
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• 1999

Effectiveness of the videotaped-record learning method in teaching intramuscular injection skill was investigated using an experimental research methodology. Data was collected from 57 female students attending Fundamental nursing class from two depts. of nursing in Chung-ju and Seoul. The subjects were assigned to two groups, the experimental group of 30 and the control group of 27. The independent variable was videotaped-record learning method and the dependent variable were the degree of knowledge achivement, nursing skill achivement, competence on practicing intramuscular injection skill and satisfaction about the learning method. Data was analyzed using descriptive statistics, chi-square test, t-test and Pearson's correlation coefficient with SPSS-PC program. The results were summarized as follows ; 1. There was statistically significant difference between the experimental group and control group in knowledge achievement about intramuscular injections (t=4.721, P=.000). 2. There was statistically significant difference between the experimental group and control group in nursing skill achievement(t=3.542, P=.001). 3. There was no statistically significant difference between the experimental group and control group in competence on practicing intramuscular injection skill (t=.627, P=.533). 4. There was statistically significant difference between the experimental group and control group in satisfaction about learning method(t=4.708, P=.000). 5. There was significant correlation between nursing skill achievement and knowledge achievement(r=.233, p<.05). In conclusion, this study suggests that videotaped-record learning method is an effective learning method for achieving intramuscular injection skill as a basic nursing skills. Therefore, further study with more developed research design and other fundamental nursing skill practice will be needed to investigate the effectiveness of videotaped-recored learning method.

• 지역사회간호학회지
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• 제14권3호
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• pp.415-423
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• 2003

Purpose: This study aims to examine whether the kinesio tape method can relax perimenstrual symptoms and decrease the menstrual pain of those who complain of perimenstrual discomforts. Method: This study has been designed to use the nonequivalent control group in the pre and post-test. The data have been collected from unmarried females complaining of perimenstrual discomfort and living in D city from the 2nd of February through the 10th of April, 2002. An experimental group of 32 people and a control group of 35 people were chosen, and they were first investigated for symptoms before and after menstruation when the menstrual pain was the severest and for the VAS measurement of menstrual pain. For the experimental group, the kinesio tape method was conducted two times a week for three weeks (six times in all), and the control group remained intact. The investigations after the experimental treatment were carried out in the same way as before. The measuring instruments were the peri menstrual measuring instruments of symptoms of 42 items and the menstrual pain was measured by VAS Result: The primary hypothesis: The experimental group who used the kinesio tape method would experience less perimenstrual discomfort than the control group who did not use it. The first sub-hypothesis: The first sub-hypothesis that suggests 'The experimental group who used the kinesio tape method would experience more relaxation of perimenstrual symptom than the control group who did not use it' was supported. The second sub-hypothesis: The second sub-hypothesis that suggests that 'The experimental group who used the kinesio tape method would get lower scores of menstrual pain of VAS than the control group who did not use it' was supported. Conclusion: These results of the study show that the kinesio tape method is effective in relaxing perimenstrual symptoms and lessening menstrual pain.

• Structural Monitoring and Maintenance
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• 제5권3호
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• pp.345-361
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• 2018

The set of processes performed to determine the dynamic characteristics of the constructed structures is named experimental modal analysis. Using experimental modal analysis and interpreting its results, structural failure can be assessed and then it would be possible to plan for their repair and maintenance. The purpose of the experimental modal analysis is to determine the resonance frequencies, mode shapes and Mode damping for the structure. Diverse methods for determining the shape of the mode by various researchers have been presented. There are pros and cons for each of these methods. This paper presents a method for determining the mode shape of the structures using the response spectrum in the experimental modal analysis. In the first part, the principles of the proposed method are described. Then, to check the accuracy of the results obtained from the proposed method, single and multiple degrees of freedom models were numerically and experimentally investigated.

• 한국문헌정보학회지
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• 제25권
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• pp.325-341
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• 1993

The experimental method, when carried out properly, is the most powerful way of seeking answers to research questions. The purpose of this study is to provide practical and theoretical insights as well as to discuss technical skills needed to design and implement the experimental research in library and information science. The levels of empirical research methods, the logic and types of the experimental designs, the application status of the experimental methods through content analysis of the published papers, and strategies to plan the research and to collect and analyze data are examined. This study also brings suggestions how experimental research can be made more meaningful and puts emphasis on the need of the research method education in library and information science field.

• 대한기계학회논문집
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• 제17권12호
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• pp.3105-3114
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• 1993

previously, several basic studies in the experimental analysis of stress intensity factors of cracks by slab analogy have been presented by authors. But, for the application of above mentioned method to the analysis of the arbitrarily distributed cracks, there still is several bottlenecks to be overcome in terms of its experimental process and data treatment. Moreover, authors recently proposed an improved experimental method to use the fixed slab analogy device which has promised more accurate measurement of S.I.F. of small cracks. In this paper, for the completion of slab analogy analysis of distributed cracks, a grating imaginary rotation method is introduced. And, to prove its validity, this combined method is applied to the determination of stress intensity factors of theoretically known distributed cracks. The results show good agreement with the existing theoretical solutions and physical crack propagation tendencies.

• 대한기계학회논문집A
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• 제24권5호
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• pp.1297-1304
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• 2000

The reflective photoelastic experiment can be used more effectively than the transparent type in industrial fields. Therefore the reflective photoelastic experimental hybrid method applied to the fatigue fracture problems is introduced in this research. It is verified that the reflective photoelastic experimental hybrid method is very useful on the determination of crack propagation velocity and stress intensity factor of the fatigue crack and on the separation of stress components in the vicinity of fatigue crack tip etc.

• 한국항해항만학회지
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• 제26권3호
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• pp.281-288
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• 2002

진동해석과 기술에 있어서 실험과 해석분야 모두 다 같이 발전한 것은 사실이지만, 실험해석법은 유한요소법과 같은 이론해석법만큼 발달한 것이라 할 수 없을 것이다. 그 이유 중에 하나로 비선형 방정식을 푸는데 있어 초기치의 선택에 따라 계산시간이 길어지고 해가 종종 발산하기도 하기 때문이다. 일반적으로 실험모드해석에 있어 방정식은 고유진동수와 감쇠비의 비선형 항과 등가강성의 선형 항으로 구성된다. 본 연구에서는 비선형 항을 먼저 구하고, 다음에 선형 항을 구하였다. 개발된 실험모드해석법(곡선맞춤법)을 선체상부구조 모델에 적용하여, 모드 특성치들을 계산하였다. 또한 개발된 프로그램은 그래픽기법을 적용하여 간단한 마우스 조작으로 채용 모드수와 감쇠비를 결정할 수 있도록 하였다.