• Journal of Aerospace System Engineering
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• v.3 no.4
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• pp.27-34
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• 2009

This paper deals with the lifetime prediction of Aircraft Flaperon Joint made of AISI 4130 steel. Reviews are performed on the published damage models at first. And three different damage models are used for predicting the fatigue life of the structure subjected to variable amplitude fatigue loading. These models require no increase in complexity of use, nor do they require additional material property or mission loading information to achieve the improved accuracy. Finally a comparison among the fatigue results is performed. It is observed that the Miner's rule could predict longer life than other cumulative damage models which take into account loads below the endurance limit.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 1997.11a
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• pp.154-161
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• 1997

Several studies have developed upward flame spread models which use somewhat different features. However, the models have not considered the transient effects of the igniter and the burning rate. Thus, the objective of this study is to examine a generalized upward flame spread model which includes these effects. We shall compare the results with results from simpler models used in the past in order to examine the importance of the simplifying assumptions. We compare these results using PMMA, and we also include experimental results for comparison. The results of the comparison indicate that flame velocity depends on the thermal properties of a material, the specific model for flame length and transient burning rate, as well as other variables including the heat flux by igniter and flame itself. The results from the generalized upward flame spread model can provide a prediction of flame velocity, flame and pyrolysis height, burnout time and position, and rate of energy output as a function of time.

• The Journal of Korean Physical Therapy
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• v.13 no.2
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• pp.313-324
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• 2001

The 15 male students of T-college which is located in Taegu, who don't have any cardiovascular diseases and skin diseases and agreed to the experiment for finding out the effects of hot and cold therapy. They were divided 5 experimental groups, that is hot therapy in blood Pressures, hot therapy group showed significantly difference of systolic blood Pressure. And the hot therapy group and hot and cold therapy showed the distinctive differences in Scheffes' s analysis after the fact. 3. There was no significant difference in pulsation between before and after experiment and there were no differences in each group. 4. The hot therapy group showed significant difference in WBC and didn't show any difference in RBC(p<.05). 5. Timing does not effect to each group in the changes of HGB and HCT. 6. In the comparison between before and after the experiments in the changes of MCV, cold therapy group showed significant measurement. And in the comparison between before and after one hour the experiment in the changes of MCV, cold therapy group showed significant measurement. The experimental group 1 and 3 showed the distinctive differences in Scheffe' s analysis after the fact(p<.05). 7. In the comparison between before and after one hour experiments in MCV changes, the cold therapy group had significant differences(p<.05). 8. There were no significant differences between before and after the experiments in MCHC changes. 9. In the comparison between before and after one hour experiments in PLT changes, cold therapy group had significant changes(p<.05) and there were no differences among three group.

• Journal of Technology Innovation
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• v.14 no.1
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• pp.119-146
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• 2006

This paper attempts to identify variables which affect Korean technology innovation-driven SMEs' performance in comparison with IT and BT industries. Technology development strategy, marketing capability, intellectual capital managerial ability are included to generate variables for the empirical research. The results of this study show that technology development strategy, marketing capability, intellectual capital managerial ability influence on the sales growth of technology-based SME in IT and BT industries. It also discusses some implications of Korean technology innovation-driven SMEs' strategy and management.

• Journal of Radiation Protection and Research
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• v.35 no.2
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• pp.81-84
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• 2010

A CSA(Charge Sensitive Amplifier) was designed and fabricated for application in a radiation detection system based on a semiconductor detector such as Si, SiC, CdZnTe and etc.. A fabricated hybrid.type CSA was evaluated by comparison with a commercially available CSA. A comparison was performed by using calculation of ENC (Equivalent Noise Charge) and by using energy resolutions of fabricated radiation detectors based on Si. In energy resolution comparison, a fabricated CSA showed almost the same performance compared with a commercial one. In this study, feasibility of a fabricated CSA was discussed.

• Korean Journal of Adult Nursing
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• v.22 no.5
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• pp.529-536
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• 2010

Purpose: This study was designed to identify the effect of auriculotherapy on low abdominal pain and dysmenorrhea in school-aged girls. Methods: This design was a pre and post-test with nonequivalent groups. The subjects were 71 girls who were middle school students with dysmenorrheal (35 students for the treatment group and 36 students for the comparison group). The subjects of the treatment group received auriculotherapy once a week for 10 weeks. The comparison group received instruction on auriculotherapy and was requested waiting for the order. Results: The treatment group reported significantly less low abdominal pain than the comparison group. However, there were not statistical differences in reported dysmenorrhea. In future analysis, 60.0% of the treatment group reported more physical comfort, and 45.7% reported more emotional cool down. Conclusion: The finding indicate that auriculotherapy could be effective in decreasing low abdominal pain during menstrual periods. Therefore, auriculotherapy could be an effective nursing intervention for low abdominal pain occurring during mensuration. However, further studies need to be done to support auriculotherapy as effective.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.822-827
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• 2005

Recently engineering systems problems become quite large and complicated. For those problems, design requirements are fairly complex. It is not easy to design such systems by considering only one discipline. Therefore, we need a design methodology that can consider various disciplines. Multidisciplinary Design Optimization (MDO) is an emerging optimization method to include multiple disciplines. So far, about seven MDO methodologies have been proposed for MDO. They are Multidisciplinary Feasible (MDF), Individual Feasible (IDF), All-at-Once (AAO), Concurrent Subspace Optimization (CSSO), Collaborative Optimization (CO), Bi-Level Integrated System Synthesis (BLISS) and Multidisciplinary Optimization Based on Independent Subspaces (MDOIS). In this research, the performances of the methods are evaluated and compared. Practical engineering problems may not be appropriate for fairness. Therefore, mathematical problems are developed for the comparison. Conditions for fair comparison are defined and the mathematical problems are defined based on the conditions. All the methods are coded and the performances of the methods are compared qualitatively as well as quantitatively.

• Journal of Astronomy and Space Sciences
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• v.21 no.3
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• pp.191-200
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• 2004

The accuracy of CCD observations obtained at the Korean 1.8m telescope has been studied. Seventeen comparison stars in the vicinity of the cataclysmic variable BG CMi have been measured. The 'artificial' star has been used instead of the 'control' star, what made possible to increase accuracy estimates by a factor of 1.3-2.1 times for 'good' and 'cloudy' nights, respectively. The algorithm of iterative determination of accuracy and weights of few comparison stars contributing to the artificial star, has been presented. The accuracy estimates for 13-mag stars are around $0.^m002$ mag for exposure times of 30 sec.

• Communications for Statistical Applications and Methods
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• v.16 no.3
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• pp.519-528
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• 2009

This paper deals with nonparametric estimation of discontinuous regression curve. Quite number of researches about this topic have been done. These researches are classified into two categories, the indirect approach and direct approach. The major goal of the indirect approach is to obtain good estimates of jump locations, whereas the major goal of the direct approach is to obtain overall good estimate of the regression curve. Thus it seems that two approaches are quite different in nature, so people say that the comparison of two approaches does not make much sense. Therefore, a thorough comparison of them is lacking. However, even though the main issue of the indirect approach is the estimation of jump locations, it is too obvious that we have an estimate of regression curve as the subsidiary result. The point is whether the subsidiary result of the indirect approach is as good as the main result of the direct approach. The performance of two approaches is compared through a simulation study and it turns out that the indirect approach is a very competitive tool for estimating discontinuous regression curve itself.

• International journal of advanced smart convergence
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• v.5 no.1
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• pp.8-15
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• 2016

Studies have been made for the wireless sensor network protocols by a number of researchers to date. In particular, the studies as to the hierarchical protocol LEACH algorithm was concentrated. Various studies have been derived for the performance of the protocol is based on the LEACH protocol have been made. Improved algorithms have been proposed continuously. On the other hand, The performance comparison and evaluation of the improved algorithm is insufficient. Therefore, we compared the performance for the ML-LEACH (Multi Hop-Layered) and DL-LEACH (Dual Hop-Layered) been derived mainly LEACH. scalability, energy consumption, CH elected, network lifetime were selected as a Performance evaluation items.