• Title/Summary/Keyword: Experimental research

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Fatigue modeling of chopped strand mat/epoxy composites

  • Shokrieh, M.M.;Esmkhania, M.;Taheri-Behrooz, F.
    • Structural Engineering and Mechanics
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    • v.50 no.2
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    • pp.231-240
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    • 2014
  • In the present research, fatigue behavior of chopped strand mat/epoxy composites has been studied with two different techniques. First, the normalized stiffness degradation approach as a well-known model for unidirectional and laminated composites was utilized to predict the fatigue behavior of chopped strand mat/epoxy composites. Then, the capability of the fatigue damage accumulation model for chopped strand mat/epoxy composites was investigated. A series of tests has been performed at different stress levels to evaluate both models with the obtained results. The results of evaluation indicate a better correlation of the normalized stiffness degradation technique with experimental results in comparison with the fatigue damage accumulation model.

Analysis of the Effect of Training Program for Parent-Adolescent Communication Applied to Home Economics Classes, and the Possibility to Implement the Program (가정과 수업에의 적용 가능성 탐색을 위한 부모자녀간 의사소통훈련 프로그램의 효과분석)

  • 박인순
    • Journal of the Korean Home Economics Association
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    • v.36 no.4
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    • pp.109-120
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    • 1998
  • The Purpose of this research was to introduce communication training program for positive parent-adolescent relation into home economics education curriculum. The research applied the program named "Making the desirable world 2" which was revised by K.E.T.I(Korea Effectiveness Training Institute). This program was given two hours a week during 8 weeks. The subject of this study was 24 students, divided into two groups, the experimental and the control group. This research supposed that parent-adolescent communication and self-esteem in the experimental group would significantly increase by group training program. The results of this research are as follows. First, parent-adolescent communication in the experimental group was significantly increased by the group training program. Second, self-esteem in the experimental group was significantly increased by the group training program. For home economics education as a practical subject matter, promoting qualitative maturity of students' family life, this study aimed both at enhancing communication for positive relation of parent-adolescent by group training and implementing home economics education curriculum practically.

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Flexural and tensile properties of a glass fiber-reinforced ultra-high-strength concrete: an experimental, micromechanical and numerical study

  • Roth, M. Jason;Slawson, Thomas R.;Flores, Omar G.
    • Computers and Concrete
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    • v.7 no.2
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    • pp.169-190
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    • 2010
  • The focus of this research effort was characterization of the flexural and tensile properties of a specific ultra-high-strength, fiber-reinforced concrete material. The material exhibited a mean unconfined compressive strength of approximately 140 MPa and was reinforced with short, randomly distributed alkali resistant glass fibers. As a part of the study, coupled experimental, analytical and numerical investigations were performed. Flexural and direct tension tests were first conducted to experimentally characterize material behavior. Following experimentation, a micromechanically-based analytical model was utilized to calculate the material's tensile failure response, which was compared to the experimental results. Lastly, to investigate the relationship between the tensile failure and flexural response, a numerical analysis of the flexural experiments was performed utilizing the experimentally developed tensile failure function. Results of the experimental, analytical and numerical investigations are presented herein.

Effect of a Health Management Program on Health Promotion in the Elderly (건강관리 프로그램이 노인의 건강관리에 미치는 영향)

  • Kim, Suhn-Yeop;Kang, Hoe-Yang
    • Physical Therapy Korea
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    • v.5 no.2
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    • pp.47-64
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    • 1998
  • The purposes of this research were to understand the realities of health management and to analyze the subjective, functional, psychological, and social health effects of the application of an exercise and education program to manage health on an elderly population residing in an agricultural community. The specific purposes of this research were: 1. to determine the subjective, functional, psychological health conditions, and performance level of instrumental activities of daily living of both the experimental and control groups before introducing a health management program, and then 2. to compare these with both the experimental and control groups' subjective, functional, psychological health condition and performance level of instrumental activities of daily living after applying the health management program. The health management program was introduced to the experimental group (50 people) but not to the control group (50 people). The health management program was composed of a health exercise program and a health education program. A comparative study of subjective health conditions was done to examine the effect of the health management program and the characteristics of health related variables before and after the program application. The results were as follows: 1. When the experimental group, which had received the 8-week health management exercise and education program, was compared with the control group, which had not, the experimental group's subjective health condition scored higher than that of the control group (p

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A Study of Sleeve Cap in the Knitwears with Plain Stitch (Plain 조직 니트 의류의 소매산 형태 연구)

  • Hong Soo-Sook;Suh Mi-A
    • The Research Journal of the Costume Culture
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    • v.14 no.3 s.62
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    • pp.404-417
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    • 2006
  • The purpose of this thesis, therefore, is to examine the shaping methods and the knitting drafts of sleeve cap in the knitwears which are currently used by the manufacturers; to study the curve forms of sleeves in knitwears by analyzing synthetically the results of investigating the problems of knit wear sleeves; to present the most suitable sleeve cap for the knitwears. As the studying methods, I collected the basic data from the working-level persons of knit wear manufacturers, examined the knitting draft in the knitwears, and from that, made three kinds of comparative experimental garments and one kind of research experimental one as 10G and 16G. In doing so, I showed the sleeve cap suitable for the knitwears with plain stitch after operating sensual evaluation with Liker's 5-point rating measure. The analysis of data was handled with statistics by using SPSS Ver. 12.0; the method of statistics was executed by Frequency Analysis, Trust Analysis, one-way ANOVA, and Duncan test according to each topic of the research. As the result of the sensual evaluation of the experimental garments produced from the study, the research experimental garment looks better than the comparative experimental one in both 10G and l6G; has less extra folds around the front part of sleeve cap; looks more natural in sleeve caps of the body part and of a sleeve. From this, I am able to figure out that the research experimental garment looks better than the comparative experimental one produced by knit wear manufacturers. In addition, I can come to know that the different knitting of the front line and the back one of armhole in the knitwears has a favorable impact on improving the appearance of a sleeve.

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Promoting and improving three Rs practice: the Korean guidelines

  • Choe, Byung In;Lee, Gwi Hyang
    • BMB Reports
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    • v.50 no.12
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    • pp.610-614
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    • 2017
  • Scientists planning research that involves the use of animals are required to examine the possibilities for replacement, reduction, or refinement (the Three Rs), and their protocol must be reviewed by the Institutional Animal Care and Use Committee. Good scientific practice involving appropriate search techniques on the available Three Rs resources is essential for both ethical and scientific reasons. Appropriate experimental design and statistical analysis techniques are particularly necessary for research involving the use of animals, because this can improve animal welfare and scientific outcomes, as well as saving animal lives. There are a number of resources to help researchers improve their search techniques, experimental design strategies, and their reporting of research involving the use of animals. However, there is little specific information or resources on the Three Rs alternatives that is readily available in the Korean language. This paper outlines the common errors made by submitting researchers that have been repeatedly observed during the ethical review of experimental protocols over the last ten years, and provides information on the Korean resources available to promote good scientific practice. This could help to bridge the gap between Korean scientists and animal welfare advocates assisting scientists to improve ethical considerations and conduct responsible research.

The Study on the influence of MBL Exhibition Class on the Eelementary school students' Academic Achievement, Scientific Research Abilities and Affective Characters (MBL 시범 수업이 초등학생의 학업성취도, 과학탐구능력 및 정의적 특성에 미치는 영향)

  • Heo, Eun-Young;Yoo, Pkyoung-Kil
    • Journal of the Korean Society of Earth Science Education
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    • v.3 no.1
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    • pp.36-46
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    • 2010
  • The purpose of this study is to find out the influence of MBL Exhibition Class on the Elementary School students' academic achievement, scientific research abilities and affective characters. For the purpose, three classes were sampled in the 5th grade of an elementary school. Among the three classes, two were designated as the comparative classes consisted of 68 students and the other was the experimental class, 33 students. The comparative classes were given lessens according to the content presented in the textbook of 7th Education Curriculum and the experimental class was given re-built lessons with using MBL machines. Before and after giving lessons, students of both classes took a test for science academic achievement. And also the scientific research abilities and affective characters were examined. The conclusions from this study is as follows. First, according to the result of science academic achievement test after giving lessons, the mean of the experimental class was higher than that of the comparative classes meaningfully. Second, scientific research abilities of the experimental class was shown higher than that of the comparative classes meaningfully. Specially, basic research abilities were improved very meaningfully and only hypothesis-building ability was improved among integrated research abilities. Third, it doesn't seem that MBL exhibition class is effective on affective characters(interest, attitudes).

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Experimental Research of Piece-Mold Casting: Gilt-Bronze Pensive Bodhisattva

  • Yun, Yong-Hyun;Cho, Nam-Chul;Doh, Jung-Mann
    • Journal of Conservation Science
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    • v.37 no.4
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    • pp.340-356
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    • 2021
  • We have tried the experimental research of lost-wax casting to reconstruct Gilt-Bronze Pensive Bodhisattva; preliminary and reconstruction experiment based on ancient texts. Main object to reconstruct is Korean National Treasure No.83, Gilt-Bronze Pensive Bodhisattva (Maitreya), then we measure alloy ratio and casting method based on the scientific analysis. Other impurities were removed from the base metal components(copper : tin : lead) and their ratio was set to 95.5 : 6.5 : 3 where the ratios for tin and lead were increased by 2.5% each. The piece-mold casting method was used, and piece-mold casting experiments were carried out twice in this study but supplementary research on piece-mold casting was necessary. The microstructure was confirmed to be typical cast microstructure and the component analysis result was similar to that of the prior study. Analysis of the chemical composition is confirmed to copper, tin, lead, and zinc, and the chemical composition of the matrix was 87.8%Cu-7.5%Sn-2.7%Pb-2.1%Zn, and similar to previous experimental research. Also resulted in the detection of small impurity in Zn. Analysis of the mould revealed that the mould was fabricated by adding quartz and organic matter for structural stability, fire resistance, and air permeability. We expect that our research will contribute to provide base data for advanced researches in future.

Pros and Cons of Various Research Designs in Clinical Psychiatry (정신과 연구에서 다양한 임상연구방법의 장단점)

  • Ha, Ra Yeon;Cho, Hyun-Sang
    • Korean Journal of Biological Psychiatry
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    • v.19 no.4
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    • pp.159-163
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    • 2012
  • An appropriate research design for hypotheses and purposes leads to a good quality of research results. In this review article, we summarized the types of research methods and described the characteristics of clinical trials. Research designs are categorized into observational studies and experimental ones, depending on data collecting methods. In an observational study, there are cross-sectional, cohort and case-control studies. Parallel groups design and crossover trial studies are representative designs in a randomized controlled trial study, a kind of experimental study. Clinical researchers should understand the characteristics of clinical research designs including advantages and disadvantages and choose the suitable design according to their study purposes and the nature of collected data or subjects.

The effects of polylactic/polyglycolic copolymer (PLA/PGA) membrane on the healing of 1-wall intrabony defects in beagle dogs (성견 1면 골 결손부에서 Polylactic/polyglycolic acid copolymer (PLA/PGA) 흡수성 차단막의 치주 조직 재생에 대한 연구)

  • Kim, Sung-Koo;Hwang, Sung-Joon;Kim, Min-Kyoung;Kim, Chang-Sung;Lee, Doug-Youn;Lee, Yong-Keun;Cho, Kyoo-Sung;Chai, Jung-Kiu;Kim, Chong-Kwan;Choi, Seong-Ho
    • Journal of Periodontal and Implant Science
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    • v.33 no.4
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    • pp.599-613
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    • 2003
  • The goal of periodontal treatment is regeneration of the periodontium. Bone graft and absorbable PLA/PGA membrane have been used for this purpose. In this study, 4${\times}$4mm 1-wall intrabony defects were surgically created bilaterally in the mandible of five male beagles. The control group went through a conventional flap operation, while the experimental group I was treated with absorbable PLA/PGA membranes only, group II was treated with absorbable membrane and calcium phosphate. The results are the following : 1. The defect height was 4.82${\pm}$0.45mm in the control group, 4.93${\pm}$0.79mm in the experimental I group, and 4.92${\pm}$0.62mm in the experimental II group. There was no statistically significant difference among 3 groups(P <0.05). 2. The amount of junctional epithelium migration was 30.90${\pm}$9.92% of the defect height in the control group, 39.16${\pm}$7.51% in the experimental I group, and 38.68${\pm}$12.22% in the experimental II group. There was no statistically significant difference among 3 groups(P <0.05). 3. The amount of connective tissue adhesion was 36.38${\pm}$9.03% in the control group, 14.73${\pm}$3.93% in experimental I group, and 27.87${\pm}$9.70% experimental II group. Experimental group I was a statistically significantly different from control group(P <0.05). 4. The amount of new cementum regeneration was 32.92${\pm}$10.51%, 50.04${\pm}$7.61%, and 39.62${\pm}$12.14% for the control, experimental I, and experimental II group respectively. Experimental group I was a statistically significantly different from control group(P<0.05). 5. The amount of new alveolar bone regeneration was 27.24${\pm}$7.49%, 40.75${\pm}$8.03%, and 36.47${\pm}$15.11% for the control, experimental I, and experimental II group respectively. Experimental group I was a statistically significantly different from control group(P <0.05). The results suggest that the use of PLA/PGA membrane in 1-wall intrabony defect of beagle dogs may promote periodontal regeneration. Further studies are required to determine their regeneration effects.