• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.1487-1492
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• 2007

In this paper, we apply a forging simulator to automatic simulation of a connecting-rod forging process and compare its results with others found in the literature. The process information comes from the distributed examples of DEFORM3D. The process is fully automatically simulated using the tetrahedral element capability of AFDEX3D, developed by the authors. Our results are compared with the results found from the related literature, already simulated using DEFORM3D by other researchers. The comparison shows that our results are relatively excellent especially in terms of mesh quality on which the solution accuracy depends mainly.

• 대한한방부인과학회지
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• 제19권4호
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• pp.77-92
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• 2006

Purpose : This study is to examine what are the effects of the Woogwiyeum(WGY) on the ovariectomized rat model of postmenopausal osteoporosis. Methods : We devide mice to 3 Group(Sham operated group, control group, WGY treated group) and analyze each serum component. Results : 1. Body weight in control group showed significant increase in comparison with sham, but that in WGY-treated showed no change in comparison with control. 2. The level of serum albumin, ALP in control group showed significant decrease in comparison with sham. That in WGY-treated was decreased in comparison with control. 3. Trabecular bone area as well as trabecular thickness in control group showed significant decrease in comparison with sham. Those in WGY-treated showed significant increase in comparison with control. 4. Osteoclast number and oseoblast surface in control group showed significant increase in comparison with sham. Those in WGY-treated showed significant decrease in comparison with control. Conclusion : WGY has shown to be capable of preventing and curing osteoporosis caused by old-aged and postmenopause.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2003년도 추계학술대회 논문집(I)
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• pp.210-215
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• 2003

Korean High Speed Train (KHST) has been tested on high speed line in JungBu site since it was developed in 2002. The KHST figured 7 cars was modeled for dynamic simulation with Vampire program. and the data acquisition system was used to test successfully the on-line test for proving the dynamic performance of KHST. The comparison between test and simulation results for dynamic behavior of KHST was tried in this paper and it was very difficult because the environmental conditions and running conditions have an effect on the test results and these conditions are unable to be modeled for dynamic analysis. Also the parameters for data acquisition system for test are usually not same to simulation conditions. Therefor, in this paper the acceleration data after filtering with low pass filter below 1Hz were used to compare between test and simulation results because the low frequency range is useful to evaluate the dynamic performance for railway vehicle system, so as steady state curving acceleration. The results show that both are similar in low frequency range.

• 대한통합의학회지
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• 제4권2호
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• pp.13-22
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• 2016

Purpose: The purpose of this study was to determine the effects of the swissball exercise in combination with core muscle in beginner golfer. In general, the swiss ball exercise was related in the core muscle ability. Methods: The experiment was conducted with a total of 10 beginner golfer, and they were dicide into two groups: comparison group(n=5) and experimental group(n=5). In this research, the subjects of the comparison group performed the general matte exercise three times a week, for four weeks. The subjects of the experimental group performed the swiss ball exercise in combination with core muscle three times a week, for four weeks. Use the 7-iron and driver were measured head speed and distance of the comparison group and the experimental group, respectively. The collected data were analyzed by using the paired t-test and ANCOVA Results: The results of this study were as follows: 1) Swiss ball exercise in combination with core muscle revealed the significant improvements after corresponding exercise in golf performance capability. 2) Mat exercise was seen less better than the swiss ball exercises. Conclusion: This results suggested that it was improved the golfer shot performance of beginner proposes to see the Swiss combined movement.

• 한국수소및신에너지학회논문집
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• 제27권6호
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• pp.737-746
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• 2016

This article describes a comparison on laminar burning velocity measured by Bunsen and spherical flame methods of synthetic natural gas (SNG) with various composition of hydrogen. In this study, the laminar burning velocity measurements were employed by Bunsen burner and cylindrical constant combustor at which flame images were captured by Schlieren system. These results were also compared with numerical based on CHEMKIN package with GRI 3.0, USC-II and UC Sandiego mechanism. In case of spherical flames, the suitable flame radius range and theoretical models were verified using the well-known previous results in methane/air flames. As an experimental condition, hydrogen content of SNG was adjusted 0% to 11%. Equivalence ratios of Bunsen flames were adjusted from 0.8 to 1.6. On the other hand, those of spherical flames were adjusted from 0.6 to 1.4, relatively. From results of this study, the both laminar burning velocities measured in Bunsen and spherical flame methods were resulted in similar tendency. As the hydrogen content increased, the laminar burning velocity also increased collectively. Laminar burning velocity of measured SNG-air flames was best coincided with GRI 3.0 mechanism by comparison of reaction mechanisms.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제53권4호
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• pp.213-223
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• 2004

In the machine tool industry, direct drive linear motor technology is of increasing interest as a means to achieve high acceleration, and to increase reliability. The advantages of such a motor are that it has a good linearity and has no need of such mechanical energy conversion parts, which change rotary motion into linear motion, as screws, gears, chains etc In this paper, two structures of LOA are analyzed. One is the moving-coil type LOA and the other is moving-magnet type LOA. Two types of LOA are analyzed, with reference to the following parameters as variables: magnetic field, flux linkage, motor thrust and back emf. These variables are derived by the use of analytical method in terms of two-dimensional rectangular coordinate system. The maximum values of thrust according to such design parameters as air-gap length and magnet height for each model is also represented. The results are validated extensively by comparison with finite element method. In particular, we experiment moving-coil LOA which is already manufactured and confirm that the experimental results are shown in good agreement with analysis through the comparison of between analytical and experimental results

• 한국지진공학회논문집
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• 제21권4호
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• pp.189-195
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• 2017

In the seismic design of building structural members, due to the complexity of the placement of PC steels in prestressed concrete members, it is necessary to review and define the definition of member damage in comparison with reinforced concrete members. In this study, the results of past experiments compared with the calculation results by 'section Analysis Method', with the aim of reviewing the precision of calculation results when member damage evaluation is performed using the section analysis method. Furthermore, it is also compared with the calculation results by the 'split Element Method'. In addition, parametric studies were carried out, and the influence of the difference between the amount of PC steels and reinforced bar on the residual strain was examined.

• 한국초등과학교육학회지:초등과학교육
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• 제32권4호
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• pp.581-592
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• 2013

Various data and methods are necessary to help students understand the science subject, and have interest in it. Most students like cartoons, and more easily memorize their contents. The purpose of this study was to verify the effects of science cartoon reading on the academic achiements, the levels of interests in science and scientific attitudes of elementary students The study subjects were four classes of the 6th grade of G elementary school in U city. Two classes were experimental group and the others were comparison group. The students of the experimental classes were encouraged to read science cartoon related to class contents at the beginning and ending for 5 minutes respectively in instructional time. And those of the comparison classes received general science lesson. The results of this study were as follows. First, the experimental classes encouraged to read science cartoon marked higher average score than comparison classes in post-test and the difference was meaningful (p<.05). This meant science cartoon reading treatment had the effect of improvement of the levels of interest in science of student. Second, the experimental classes marked higher average score than comparison classes in post-test but didn't show meaningful difference. This meant science cartoon reading treatment didn't have the effect of improvement of academic achievement of students in our study. Third, the experimental classes marked higher average score than comparison classes in post-test and showed the meaningful difference(p<.05). This meant science cartoon reading treatment had the effect of improvement of scientific attitudes of students. From the results thus far, we could tell that science cartoon reading had positive effects on the levels of interest in science and scientific attitudes of students in our study.

• Steel and Composite Structures
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• 제49권1호
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• pp.31-45
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• 2023

The network theory studies interconnection between discrete objects to find about the behavior of a collection of objects. Also, nanomaterials are a collection of discrete atoms interconnected together to perform a specific task of mechanical or/and electrical type. Therefore, it is reasonable to use the network theory in the study of behavior of super-molecule in sport nano-scale. In the current study, we aim to examine vibrational behavior of spherical nanostructured composite with different geometrical and materials properties. In this regard, a specific shear deformation displacement theory, classical elasticity theory and analytical solution to find the natural frequency of the spherical nano-composite sport structure equipment. The analytical results are validated by comparison to finite element (FE). Further, a detail comprehensive results of frequency variations are presented in terms of different parameters. It is revealed that the current methodology provides accurate results in comparison to FE results. On the other hand, different geometrical and weight fraction have influential role in determining frequency of the structure.

• 사상체질의학회지
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• 제24권4호
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• pp.62-74
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• 2012

Objectives : The purpose of this study is to investigate the effect of oral administration of Yongyukjowi-tang(YJT) on the immune activity in aged Sprague-Dawley rat(SD rat). Methods : SD rats were divided into three groups: Yongyukjowi-tang groups(YJT groups), distilled water groups(control groups) and Vitamin C groups(positive control groups) which were administered an oral dose(1ml/1day) to 6, 48 and 68 weeks old SD rats for four weeks. After four weeks, the number of total leukocyte, CD3+, CD4+, CD8+, and the level of cytokine (IL-2, IL-4, IL-10, IFN-${\gamma}$) were measured in spleen tissue of each SD rats. Results and Conclusions : 1) The number of total leukocyte significantly increased in 52 weeks old YJT group and 72 weeks old YJT group in comparison with those of the control group. 2) The number of CD3+ cell significantly increased in 72 weeks old YJT group in comparison with those of the control group and the positive control group. 3) The number of CD8+ cell significantly increased in 52 weeks old YJT group in comparison with those of the control group. 4) The level of IL-2 significantly increased in 72 weeks old YJT group in comparison with those of the control group and the positive control group. 5) The level of IL-4 significantly increased in 52 weeks old YJT group in comparison with those of the positive control group. These results suggest that oral administration of YJT has an effect on increase of immune activity in aged rat.