• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1998.03a
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• pp.274-280
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• 1998

The welding technology and qualities are developed significantly, in recent years, in the use of automated processing technology and welding robot systems. But these automated welding technologies have many difficulties for finding the optimal welding parameter conditions. Because of the lack of mathematical model for determination of optimal welding process parameters. In this study, the sensitivity analysis of the empirical equations for finding weld bead width, height and penetration depth by using the published formulae. The selected major welding process parameters effected to weld bead geometries are the welding speed, current, voltage and weld wire diameter.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.14 no.9 s.90
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• pp.801-810
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• 2004

Parameter modification of a linear finite element model(FEM) based on modal sensitivity matrix is usually performed through an effort to match FEM modal data to experimental ones. However, there are cases where this method can't be applied successfully; lack of reliable modal data and ill-conditioning of the modal sensitivity matrix constitute such cases. In this research, a novel concept of introducing feedback loops to the conventional modal test setup is proposed. This method uses closed-loop natural frequency data for parameter modification to overcome the problems associated with the conventional method based on modal sensitivity matrix. We proposed the whole procedure of parameter modification using the closed-loop natural frequency data including the modal sensitivity modification and controller design method. Proposed controller design method is efficient in changing modes. Numerical simulation of parameter estimation based on time-domain input/output data is provided to demonstrate the estimation performance of the proposed method.

• Journal of Environmental Science International
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• v.19 no.5
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• pp.655-663
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• 2010

Today, the importance of environmental education is a matter we are all concerned about. The environment surrounding us, such as the air we breathe, the water we drink, and the soil plants grow in, is critical for our survival. Currently there is a lot of interest in environmental education at the elementary, middle, and high school levels. This is a result of the deep recognition of the importance of the environment. However the environmental education being conducted in schools is not yet at a satisfactory level. The practical issues, including an entrance exam-oriented atmosphere, student' and parents' lack of understanding, and teachers' lack of expertise in environmental education, interfere with the stability of environmental curriculum in the schools. Accordingly, we need to devise an alternative environmental curriculum due to the fact that it hasn't been included as a regular subject in the curriculum of many national schools. This study, carried out from April to December 2009, was an examination of the effect of volunteer work at the place of ecology experience on the environmental sensitivity & state-trait anxiety of the 61 Gifted Students. The students were divided into two groups. The test group consisted of 30 gifted students who did volunteer work at the place of ecology experience run by Ulsan Science High School, in Ulsan Metropolitan City. The control group consisted of the rest of the students. The following are the study results: First, the volunteer work at the place of ecology experience was influential in increasing the environmental sensitivity of the gifted students. Second, the volunteer work at the place of ecology experience was influential in decreasing the state anxiety of in gifted students. Third, the volunteer work at the place of ecology experience was influential in decreasing the trait anxiety of in gifted students. Fourth, the volunteer work at the place of ecology experience positively influenced not only the gifted students' view of environmental education, but also their overall character.

• Journal of the Korean Home Economics Association
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• v.41 no.9
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• pp.69-83
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• 2003

Today, because of the consumers who should constantly decide which to buy in a flood of information can't search for complete information by the limited time and the lack of the ability in evaluating the goods, the price being important as the information clue in consumers' goods or dependence on the price will be gradually increasing. The purpose of this study is to know how much price sensitivity recognized by consumers will have and effect on buying feeling of satisfaction in internet shopping mall. The result of this study is that the consumers' target-oriented behavior searching appropriate price for buying goods in internet shopping mall substantially elevates the price sensitivity and shapes the positive attitude toward the feeling of satisfaction. It is meaningful in that it has provided the base for studying the price sensitivity centering around some limited factors through actual proof of how the consumers respond to the price at this point of activating online transactions.

• Journal of Acupuncture Research
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• v.28 no.2
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• pp.133-141
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• 2011

Objectives : Although the thermo-sensitivity test in Well points in 12 Meridians(井穴知熱感度測定法) has been used for several decades, it is still performed by a manual way, and lack in objectivity consequently. To make it more objective, accurate and convenient test, we have developed a novel system to test thermo-sensitivity in Well points. Methods : To enhance the blindness of the test, we made a shielded system which give heat to some fingers of subjects in random way. To perform the test in quantitative manner, we developed a fully automated, computer-controlled system composed of heating bulbs and response button array. Results : The developed system showed linearity in heating the finger phantom. It also gave acceptable but interesting features in pilot tests with several young adult subjects. Conclusions : By the developed system, we could improve objectivity and convenience of the thermo-sensitivity test in Well points.

• Structural Engineering and Mechanics
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• v.17 no.6
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• pp.767-788
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• 2004

The classical 8-node isoparametric serendipity element uses parametric shape functions for both test and trial functions. Although this element performs well in general, it yields poor results under severe mesh distortions. The distortion sensitivity is caused by the lack of continuity and/or completeness of shape functions used for test and trial functions. A recent element using parametric and metric shape functions for constructing the test and trial functions exhibits distortion immunity. This paper discusses the choice of parametric or metric shape functions as the basis for test and/or trial functions, satisfaction of continuity and completeness requirements, and their connection to distortion sensitivity. Also, the performances of four types of elements, viz., parametric, metric, parametric-metric, and metric-parametric, are compared for distorted meshes, and their merits and demerits are discussed.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.1043-1049
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• 2008

Trouble by excessive axial stress in CWR layed on a bridge is frequently happen, and this problem is induced from lack of considering on the track/structure interface on preliminary design stage. In this study, the sensitivity evaluation for the major influencing parameters, that is, expansion length of span, stiffness of super structure, arrangement of bearing, and strength of sub-structure, to the axial force in CWR on a bridge is conducted. From the sensitivity study, the guideline to reduce axial force efficiently in CWR for bridge engineer was suggested. The suggested guideline may not applicable for every case, but it is helpful for preliminary design of bridge.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.3
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• pp.355-360
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• 2012

It is difficult to converge power flow for the power system planning data. The main cause of power flow diverse is reactive power imbalance. A active power could be adjust by ELD or merit order but a reactive power couldn't dispatch before power flow analysis. The lack of reactive power of power system is cause a inadequate voltage drop This paper suggest new reactive power dispatch algorithm using switched shunt admittance. This algorithm uses reactive power sensitivity called switch shunt jacobian. When proposed algorithm applies to real system data that couldn't be conversed in PSS/E the power flow analysis is converged.

• Journal of The Korean Society of Agricultural Engineers
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• v.57 no.1
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• pp.99-109
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• 2015

In the construction industry, the interest for recycling aggregates is rising as more people demand for alternatives due to lack of supply of natural aggregates and environmental problems. However, in order for recycled aggregates to be used in infrastructures, stability and other factors need to be verified. Therefore, the objective of this study is to analyze the sensitivity of soil properties to secure slope safety according to various heights of embankment when bottom ash and dredged soil mixture is applied in the embankment. In most cases, all heights were safe for the slide for the embankment whether the water level is full or sudden draw down. The result of the sensitivity analysis revealed that the unit weight of embankments is highest among all factors to be considered. However, the sensitivity of the unit weight became smaller and the sensitivity of the friction angle of embankments increased with the height of embankments. The sensitivity of factors of core materials is very small because the core has weaker physical properties than those of the embankment. The effect of the height for each factor is different for each slope and water levels. The sensitivity of the unit weight of embankments is most affected when the height is 60m in the upstream slope. To conclude, bottom ash and dredged soil mixture can be applied in the embankment and different factors must be considered in different scale because the sensitivity depends highly on the height of embankments.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.6
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• pp.240-251
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• 2018

This study was conducted to evaluate the moral distress, moral sensitivity, and the factors that influence moral distress and the experience of moral distress among nurse working in a long-term care hospital. Overall, 180 nurses working in long-term care hospital in G Province were evaluated. Date were collected from March 21 to April 8, 2016 and analyzed using the SPSS/WIN 23.0 program. The mean of moral distress among nurses was 3.57 and the moral sensitivity was 4.82, and these factors was significantly and positively correlated (r=0.494, p<0.001). Regression analysis revealed that the factors that significantly influenced moral distress were moral sensitivity and ethical dilemmas when conducting nursing practices. Situations that caused nurses to experience moral distress included inappropriate care behavior was not guaranteed the quality of nursing care, conditions related to unethical the human rights, conditions related to the lack of nursing staff and conditions related to the lack of support at the organizational and national level. Therefore, to reduce moral distress, nursing intervention programs that improve the moral sensitivity and ability to solve ethical-problems are needed for nurses working in long-term care facilities.