• Journal of The Korean Association For Science Education
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• v.21 no.3
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• pp.547-557
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• 2001

In this study, we compared the contents of cloud making experiments in middle school science textbooks of 5th and 6th science curriculum from the viewpoint of methods and apparatus. And we analyzed the problems of the experimental methods and apparatus based on the thermodynamic theories. A new experiment was developed to solve the problems, and the effects of new experiment were compared with those of the experiments in the textbooks.

• Journal of the Korean Applied Science and Technology
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• v.37 no.5
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• pp.1298-1305
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• 2020

Objective: The study aimed to understand the degree of improvement in damaged hair by applying mink oil. Methods: The agent used to improve hair texture is mink oil, which was applied in varying dosages (0, 1, 2, and 3 g). Hair characteristics were measured before and after applying mink oil to bleached hair for comparative analysis. To understand the effects of mink oil on hair texture, tensile strength, absorbance, and gloss were measured. Results: The results indicate a decrease in the tensile strength of damaged hair compared with healthy hair. Tensile strength at level 7 was achieved with high dosages of mink oil. Furthermore, the experimental group demonstrated an increase in absorbance compared with control. Compared to 0g for the control group, the absorbance values for the experimental group with mink oil dosages of 1, 2, and 3 g at level 7 decreased with the increased in mink oil dose. In terms of gloss, an increase was observed for bleached hair compared with healthy hair. At level 7, gloss decreased with the increase in mink oil dose. Conclusions: The results verified the improvement in hair texture after the application of mink oil to damaged hair. Future research should explore the effects of various oil ingredients on hair texture.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2004.06a
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• pp.292-303
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• 2004

The previous exponential experiment system has been improved for the automatical and accurate axial movement of the neutron source and detector with attaching the automatical control system which consists of a Programmable Logical Controller(PLC) and a stepping motor set. The automatic control program which controls MCA and PLC consistently has been also developed on the basis of GENIE 2000 Library. The exponential experiments have been carried out for Kori 1 unit spent fuel assemblies, Cl4, Jl4 and G23, and Kori 2 unit spent fuel assembly, J44, using the improved systematical measurement system. As the results, the average exponential decay constants for 4 assemblies are determined to be 0.1302, 0.1267, 0.1247, and 0.1210, respectively, with the application of Poisson regression.

• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.1818-1822
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• 2008

Generally, not only in order to design three dimensional hydraulic structures such a spillway and to investigate the hydraulic phenomena concerning hydraulic facilities, but also to grasp shape and stability, we simulate actuality phenomenon through hydraulic model experiments. However, it requires too much times, expense and space to perform hydraulic model experiments, as well as it is very difficult to measure reduced scale of actual hydraulic structures. Besides, surface tension can exert fair effect in experiment result, and occasionally an experiment of various case is impossible actually. Therefore, there is necessity to draw proper early result through numerical analysis, and if decide the case of a hydraulic model experiment through the numerical analysis and compare the result, finally economical and reasonable design hydraulic structures are available. This study performs numerical analysis of overflow spillway and an experimental study of hydraulic model tests to design the optimal spillway and suggest a better design to improve hydraulic conditions. From the measurements, revised designs for an hydraulic structure are suggested and consequent improvement effects by the new design are also investigated.

• Journal of Naturopathy
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• v.11 no.1
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• pp.9-17
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• 2022

Background: No studies have reported on the effects of loess beddings on insomnia patients. Purpose: It studied the change in quality of life and quality of sleep after having 15 insomnia subjects use the bedding that emits far-infrared rays. Methods: After using loess bedding for the test group and general yellow bedding for the control group, the study was conducted in the form of a questionnaire on the WHO quality of life of the subjects. Results: In the overall quality of life evaluation, the pre-and post-changes significantly improved in the test group. Using loess bedding was greatly enhanced the physical change, the actual sleep time, and the quality of sleep of the test group. The period of sleep was significantly longer post-treating, and the habitual sleep efficiency was considerably higher, and sleep disturbance was significantly lower than before in the test group. Sleep drug use and daytime dysfunction after treating in the test group significantly improved the sleep effect. Changes in the Sociality Scale, Environmental Change Scale, and Quality of Life Scale significantly improved in the test group. The quality of life for 14 items in the test group was significantly correlated. Daytime drowsiness, depression, and anxiety scale changes were significantly improved in the test group. According to the predictive survey, the subjects felt warmth in their body and comfort in mind during and after using loess bedding and evaluated that sleep quality was good. Conclusions: The overall quality of life in the test group increased using loess bedding.

• 한국지구과학회:학술대회논문집
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• 2004.02a
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• pp.34-34
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• 2004

• Journal of the Korean Chemical Society
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• v.66 no.3
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• pp.218-227
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• 2022

The purpose of this study is to analyze the opinions of students by using the text mining to the good points and improvements among the descriptive course evaluation written by the students who participated in the university chemistry laboratory class, and to derive the improvement for the class. We analyzed the frequency of occurrence, co-occurrence and network of key words. As a result of the study, in the network of good points in the class, the most frequent mentions were made between class and professor, along with explanation, understanding, student, passion, fun, TA, experiment, help, etc. In the network of improvements in the class, the most frequent mentions were made between class and student, along with professor, content, explanation, exam, wish, experiment, understanding, difficult, thought, problem, etc. In other words, the students suggested the opinion that the contents of the class were well understood and that they felt fun and satisfied with the experimental process due to 'easy and detailed explanation' and 'TA's assistance' as good points of the class. On the other hand, the students suggested the negative opinions that the understanding and concentration in the class was decreased due to 'difficulty of content and exam', 'excessive assignments', and 'class environment' as improvements of the class.

• Journal of the Korean Society of Food Culture
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• v.20 no.4
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• pp.397-404
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• 2005

본 연구는 외식산업을 대상으로 6시그마에서 사용하는 프로세스 개선의 접근방식과 그 통계적 기법을 활용하여, 고객만족의 핵심요인 중의 하나인 음식 맛의 일관성을 구현하는 방안을 제시하고자 하였다. 연구방법으로는, 프로세스 개선을 위한 6시그마 로드맵 DMAIC(Define, Measure, Analyze, Improve, Control) 방식을 사용하였고, 연구대상은 단체급식에서 사용하는 특정 메뉴를 중심으로 하였고, 관련 데이터는 해당 기업에서 실험한 자료와 전문가 집단을 대상으로 한 Brainstorming, Matrix 분석기법, 그리고 상관분석과 t-test 등을 통해 특정메뉴(돈육고추장볶음)의 조리작업에 필요한 구성요소 -식재료 및 조리방법-를 제시하고 이들 중에서 가장 적합한 맛을 만들기 위한 최적의 조합을 도출한 결과, 해당메뉴의 양념을 구성하는 마늘, 고춧가루, 참기름의 구성비가 제시되었다. 이 외에도 조리방식과 비용 측면에서도 최적의 조건을 도출함으로써 음식 맛의 개선과 품질관리의 일관성 방안이 제시되었다.

• Korean Management Science Review
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• v.8 no.1
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• pp.127-133
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• 1991

본 연구에서는 Karmarkar법의 변형인 Todd&Burrell 알고리즘을 분석하고 이 알고리즘의 수행속도를 증가시키기 위한 몇가지 방안을 제시하였다. 또한, 몇가지 실험을 통하여 제안된 방안들을 비교 분석하였다. 사영행렬의 계산에 QR 분해법과 Cholesky 분해법을 도입함으로써 계산 시간을 줄일 수 있었고, 구내최적화를 위한 개선폭의 결정에 비율검정법과 선형탐색법을 사용함으로써 수행횟수 및 총 수행시간을 줄일 수 있었다. 수행실험을 통하여 알고리즘을 분석한 결과, 수행시간의 대부분을 사영행렬의 계산이 차지하는 것으로 나타나 이론적으로 계산복잡도를 분석한 결과와 일치하였다. 또한, 사영행렬과 개선폭의 결정에 사용된 각 방법들을 실험을 통해 비교 분석한 바로는 사영행렬의 계산에 있어서 Cholesky 분해법이 Gauss소거법이나 QR 분해법을 쓰는 경우보다 우수했으며, 개선폭을 결정하는 데 있어서는 비율검정법이 속도면에서 가장 우수했다.

• Journal of Biomedical Engineering Research
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• v.21 no.2
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• pp.109-118
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• 2000

본 논문에서는 일반적인 초음파 의료 영상 시스템에서 제공되는 단면 영상의 화질을 현저히 향상시킬 수 있는 영향 개선 기법들을 제안하였다. 제안된 기법들은 현재 대부분의 초음파 영상 시스템에 적용되는 접속기법과는 달리 한 프레임에 해당하는 RF 수신 신호들을 저장하고 합성구경 기법에 기반해서 수신신호들을 처리함으로써, 초음파 영상의 화질을 결정하는 주요 성능 변수인 해상도, 신호 대 잡음비, 주사속도 등을 개선시킬 수 있다. 제안된 기법들을 검증하기 위하여 RF 수신신호들을 저장할 수 있는 실험 장치를 제작한 후 실제 실험을 통하여 성능 평가를 수행하였다. 실험 결과 기존 시스템에 비해서 매우 우수한 영상을 얻을 수 있었으며, 시편 및 인체 데이터 경우에 모두 동일한 효과가 나타남을 확인 할 수 있었다.