• Journal of the Korean Society for Precision Engineering
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• v.21 no.6
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• pp.77-83
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• 2004

Cutting by a high speed laser cutting machine is one of most effective technologies to improve productivity. This paper has studied to obtain the cutting characteristics and optimal cutting conditions in a high speed feeding type laser cutting machine by Tacuchi method in design of experiments. A Lf(34) orthogonal array is adopted to study the effect of adjustment parameter. The adjustment parameters consist of cutting speed, laser power, laser output duty and assistant gas pressure. And the quality feature is selected as surface roughness of sheet metal. Variance analysis is performed in order to evaluate the effect of adjustment parameters on the quality feature of laser cutting process.

• Smart Structures and Systems
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• v.24 no.2
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• pp.193-207
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• 2019

This study concerns with morphing structures, e.g. as applied in the aerospace industry. A morphing aerofoil structure capable of variable geometry was developed, which was shown to be able to cater for the different aerodynamic requirements at different stages of flight. In this work, the useful and relatively simple method has been applied, which provides a direct method for calculating required morphing shape displacements via finding the most effective bar through calculating bar sensitivity to displacement and calculating set of length actuations for bar assembly to control/adjust shape imperfection of prestressable structural assemblies including complex elements ("macro-elements", e.g., the pantographic element), involving Matrix Condensation. The technique has been verified by experiments on the physical model of an aerofoil shaped morphing pantographic structure. Overall, experimental results agree well with theoretical prediction. Furthermore, the technique of multi-iteration adjustment was presented that effective in eliminating errors that occur in the practical adjustment process itself. It has been demonstrated by the experiments on the physical model of pantographic morphing structure. Finally, the study discusses identification of the most effective bars with the objective of minimal number of actuators or minimum actuation.

• Proceedings of the Korean Statistical Society Conference
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• 2004.11a
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• pp.179-184
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• 2004

Statistical process control (SPC) and engineering process control (EPC) are based on different strategies for process quality improvement. SPC reduces process variability by detecting and eliminating special causes of process variation, while EPC reduces process variability by adjusting compensatory variables to keep the quality variable close to target. Recently there has been need for an integrated process control (IPC) procedure which combines the two strategies. This article considers a scheme that simultaneously applies SPC and EPC techniques to reduce the variation of a process. The process disturbance model under consideration is an IMA(1,1) model with a location shift. The EPC part of the scheme adjusts the process, while the SPC part of the scheme detects the occurrence of a special cause. For adjusting the process repeated adjustment is applied by compensating the predicted deviation from target. For detecting special causes the two kinds of exponentially weighted moving average (EWMA) control chart are applied to the observed deviations: One for detecting location shift and the other for detecting increment of variability. It was assumed that the adjustment of the process under the presence of a special cause may change any of the process parameters as well as the system gain. The effectiveness of the IPC scheme is evaluated in the context of the average cost per unit time (ACU) during the operation of the scheme. One major objective of this article is to investigate the effects of the process parameters to the ACU. Another major objective is to give a practical guide for the efficient selection of the parameters of the two EWMA control charts.

• The Journal of the Korea Contents Association
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• v.13 no.7
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• pp.463-472
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• 2013

The purpose of this study is to examine the relationships among three factors such as the family health, school adjustment and internet addiction, and their subordinated factors. The research is going to clarify if school adjustment has mediating effect in the relationship between the family health and internet addiction. 371 of elementary school students resideing in Dadjeon-city completed questionnaires assessing family health, school adjustment and internet addiction. The sample variance-covariance matrix was analyzed using SPSS 18.0 and AMOS 20.0, the mazimum likelihood minimization function. The goodness of fit was evaluated using the SRMR, RMSEA and its 90% confidence interval, CFI, and TLI. The results are as follows: First, there were significant correlations among family health, school adjustment and internet addiction. Second, the subordinated factors in the family health, school adjustment, and internet addiction regulation are also closely related in the statistically significant positive relationship excepting school adjustment. After conducting the Covariance Structure Analysis to verify the mediating effect of school adjustment in the relationship between the family health and internet addiction, we found that it was appropriate to explain our findings with the structural equation model. when the family health has an effect on internet addiction, the school adjustment partially influences this process. Finally, educational implications and suggestions for future studies are addressed.

• The KIPS Transactions:PartD
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• v.15D no.1
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• pp.61-72
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• 2008

One of the most significant tasks of software development project is to know how much it will be the software development cost in the early stage of software development cycle. The software development environment and technology are changing very rapidly. For accuracy, we should apply those to the software cost estimation. And it is important that we select the suitable adjustment factor and the value of a suitable adjustment factor. For that, this paper have applied the method of AHP. And we have also analyzed the sensitivity of the adjustment factor which is influenced by decision metrics. In conclusion, the value of the application type adjustment factor is responded more sensitively to the data complexity and the control complexity than processing complexity. And the value of the language adjustment factor is responded more sensitively to the supplying manpower and the time of the coding than the time of the debugging. In the future, we will research the selection of an additional adjustment factor and a suitable value of the adjustment factor which are influenced by the environment and the technology of the domestic software development. And then, in the language adjustment factor, we will try to calculate the value about the individual programming language.

• The Korean Journal of Community Living Science
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• v.24 no.1
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• pp.71-84
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• 2013

In this study we examine the relationship between the social participation in the early adolescents and school adjustment as well as the mediating effects of a sense of community. Findings provide ways of intervention that can increase a youth's school life. Based on samples of 2,351 first grade middle school students from the data in the 'Korea Youth Panel Survey' administered by the National Youth Policy Institute, we analysed the correlation among the variables. The results are as follows. First, the social participation of youths showed a major influence on school adjustment, and was identified as: the more the students participate in social activities, the better the students get adjusted to school. Second, the social participation has a significant effect on sense of community. In other words, the more the students participate in social activities, the more the students get a sense of community. Third, a sense of community mediated the process of social participation on school adjustment. These findings indicate that in order to increase a youth's school adjustment, a promotion of social participation and an effort to increase a sense of community are required. The implications of these findings suggest that by intervening social welfare and policy, can improve the integrity of a youth's school life.

• The Journal of the Korea Contents Association
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• v.19 no.5
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• pp.35-47
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• 2019

The purpose of this study in to verify the impact of gratitude disposition and academic self-efficacy on the process in which academic stress of college freshman are affected in adjustment to college. For this, research models were established based on prior studies and processes were verified through correlation analysis and structural equation analysis. Data was collected from 1785 freshman students from college in Incheon. Four measurement instruments were employed: Academic Stress Scale, Gratitude Questionnaire, Academic Self-Efficacy Scale, Students Adjustment to College Questionnaire. The results showed that academic stress showed negative effect on adjustment to college, gratitude disposition, and academic self-efficacy. The dual mediation effect by gratitude disposition and academic self-efficacy was also verified. Implications for adjustment to college and academic guidance, limitations of the study and suggestions for future researches are discussed.

• Korea Trade Review
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• v.44 no.5
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• pp.1-16
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• 2019

As the activities of global enterprises have become more globalized and the labor movement among nations has increased, many studies have been carried out on the effective adjustment of expatriate managers. By examining the literature over the past 30 years on the adjustment of expatriate managers, this study identified major research trends and presented future research directions. While prior studies have often been cumbersome, time-consuming, and dependent on the researchers' subjective judgments, this study performs a bibliometric analysis using quantitative and visualized reference materials to provide a map showing the evolution process of existing research on the adjustment of expatriates. Using the CiteSpace program, this study conducted a bibliometric analysis of 517 papers focusing on major research trends, research countries, research institutions, authors, and journals. Study results found that the study of international adjustment was mainly focused on self-directed senders, attribution adaptations, and personal characteristics. The United States, Britain, and Australia were the most represented countries, while the most influential institutions included Aarhus University, the University of Wisconsin, and Hong Kong Baptist University. As one of the leading researchers, Selmer of Orhuss University published 19 papers, followed by Luring of Orhuss University. The Journal of International Business Studies (JIBs) most frequently featured studies of overseas expatriate adjustment.

• Journal of the Korea Society for Simulation
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• v.19 no.4
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• pp.111-122
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• 2010

In this study, a length adjustment algorithm for cyclic signals in manufacturing process using Time Invariant Feature point Extraction and Matching(TIFEM) is proposed. In order to precisely compensate the length of cyclic signals which have irregular length in the middle of signal as well as in the full length more feature points are needed. The extracted feature must involve information about the pattern of signal and should have invariant properties on time and scale. The proposed TIFEM algorithm extracts features having the intrinsic properties of the signal characteristics at first. By using those extracted features, feature vector is constructed for each time point. Among those extracted features, the only effective features are filtered and are chosen such as basis for the length adjustment. And then the partial length adjustment is performed by matching feature points. To verify the performance of the proposed algorithm, the experiments were performed with the experimental data mimicking the three kinds of signals generated from the actual semiconductor process.

• East Asian mathematical journal
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• v.31 no.4
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• pp.393-420
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• 2015

The expectation and confirmation emerging as one of problem-solving strategies in the elementary school is a strategy that does not limited in the elementary school but used in the middle and high school. This strategy inevitably requires a process of adjustment that affected by the earlier expectation. Such an adjustment raised expectation and confirmation to one of effective problem-solving strategies. The adjustment is especially important to carry out the strategy effectively. The aim of this study was to conduct basic research on cognitive characteristics appearing to students when they carried out the expectation and confirmation strategy. We investigated and analyzed this in term of adjustment of expectation. To do this, we examined 50 5th graders' response in three kinds of word problems and interviewed with 4 participants who is using the expectation and confirmation strategy. The interview was conducted by using the items or solutions used in the test. From this, we tried to check students' cognitive characteristics and recognition on it's value. Furthermore we proposed the pedagogical implications associated with these results.