• Journal of the Korean Society for Precision Engineering
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• v.21 no.11
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• pp.130-139
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• 2004

The Casing Oscillator is a bore file Equipment for the all-casing process. All-casing process is a method of foundation work in construction yard to oscillate steel Casing in the ground. The existing Casing Oscillator has some problem like not boring horizontally with disturbance and not driving Casing othor angle except horizon. To solve problem, the new structure Casing Oscillator is presented and studied. The performance of Casing Oscillator is improved by kinematics analysis. The Casing Oscillator is similar to the parallel manipulator in structure. So we obtain Inverse kinematics solution of Casing Oscillator easily. But it is difficult to solve forward kinematics of Casing Oscillator. T his paper presents a novel pose description corresponding to the structure characteristics of parallel manipulators. Through analysis on geometry theory, we obtain a new method of the closed-form solution to the forward kinematics using Kinematic Inversion. The closed-form solution contains two different meanings -analytical and real-time. So we reach the goal of practical application and control. Closed-form forward kinematics solution is verified by an inverse kinematics analysis. It shows that the method has a practical value for real -time control and inverse kinematics servo control.

• Transactions of the Korean Society of Mechanical Engineers
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• v.11 no.2
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• pp.271-278
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• 1987

The experimental study was carried out to investigate the pressure fluctuation, operating frequency, noise emission and combustion characteristics in an aero-valved pulsating combustor. Measurements of the pressure fluctuation, mean temperature and ion current inside the combustion chamber indicate that combustion phenomena are characteristically similar to those in the diffusion flame. The measured frequency schedue indicates that the acoustic theory of the quarter wave tube can be approximated to give the operating frequency, but correction factor must be involved to estimate the correct operating frequency. The spectral behavior of the noise emission exhibits that frequency bands with high noise intensity are narrowly restricted to the neighborhood of the operating frequency signalling the low-frequency combustion characteristics of the pulsating combustor. Measurements of the operating characteristics as variation of the fuel nozzle diameter and injection angle with 4 fuel nozzles have been made, and it was found that the system produced the stable operating conditions up to the turn down ratio of 3 when the fuel nozzle diameter is 1.2mm, and the optimum fuel injection angle is thought to be in the neighborhood of 30.deg. radially.

• Journal of KIISE:Computer Systems and Theory
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• v.29 no.4
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• pp.185-191
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• 2002

In this paper, we propose a 3D object LOD(Level of Detail) modeling system that constructs a mesh from range images and generates the mesh of various LOD using the wavelet transform. In the initial mesh generation, we use the marching cube algorithm. We modify the original algorithm to apply it to construct the mesh from multiple range images efficiently. To get the base mesh we use the decimation algorithm which simplifies a mesh with preserving the topology Finally, when reconstructing new mesh which is similar to initial mesh we calculate the wavelet coefficients by using the wavelet transform. We solve the critical problem of wavelet-based methods - the surface crease problem (1) - by using the mesh simplification as the base mesh generation method.

• Journal of the Korean Institute of Intelligent Systems
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• v.17 no.5
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• pp.679-683
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• 2007

Statistical learning theory by Vapnik consists of support vector machine(SVM), support vector regression(SVR), and support vector clustering(SVC) for classification, regression, and clustering respectively. In this algorithms, SVC is good clustering algorithm using support vectors based on Gaussian kernel function. But, similar to SVM and SVR, SVC needs to determine kernel parameters and regularization constant optimally. In general, the parameters have been determined by the arts of researchers and grid search which is demanded computing time heavily. In this paper, we propose a differential evolution based SVC(DESVC) which combines differential evolution into SVC for efficient selection of kernel parameters and regularization constant. To verify improved performance of our DESVC, we make experiments using the data sets from UCI machine learning repository and simulation.

• Korean Medical Education Review
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• v.15 no.1
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• pp.19-24
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• 2013

In medicine, rapid changes in information, technology, socio-economic interests, and globalization affect the medical education focused on the competencies of doctors, and the number of medical schools that are adopting an outcome-based curriculum (OBC) is increasing worldwide. This paper introduces the OBC model of 5 trailblazing medical schools from the UK, US, and Australia, comparing their unique features, followed by brief comment about Canada and the EU as well. On developing an OBC, the process of establishing the top outcomes for graduates is similar and the outcomes comprise knowledge, skills, and attitudes about science, patients, colleagues, society, and themselves. Implementing the outcomes down into the sub-levels of the curriculum is much more complicated and time-consuming. Assessing the achievement of every outcome is essential and requires the use of many tools in addition to the traditional written examination. From the perspective of adult learning theory, self-directed learning, team-learning, and individual and flexible achievement are tested and executed in an OBC. The gradual expansion and further innovation of an OBC is expected so that tomorrow's doctors will be able to meet the challenges of the future.

• The Journal of the Convergence on Culture Technology
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• v.5 no.4
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• pp.157-169
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• 2019

The purpose of the present study was to prepare baseline data for developing nursing theory and knowledge by analyzing the concept of taeoom among the nurses and by investigating the differences from the similar concept of workplace bullying. This study carried out an analysis after perusing 15 articles selected from 125 research articles retrieved according to the evolutionary method of Rodgers. The attributes of taeoom found in the present study were passage rites, painful human relationships, verbal attacks, and working relationships. There is a clear difference in concept between taeoom and workplace bullying, therefore the two concepts should be used discriminatively in nursing research. In addition, by the dynamic changes of the properties of taeoom according to the times and social circumstances, the concept of taeoom is gradually expanding and changing negatively.

• The Journal of Korean Medical History
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• v.34 no.2
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• pp.65-77
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• 2021

Lee Jema said in his book, Dongui Susebowon, that the prescriptions for Soum constitutional type were already developed by doctors during the Song Jin Yuan China around 10th-13th century. Those prescriptions were common techniques that were used throughout the East Asian region. Among them, Lee Jema specially selected some candidate formulas and modified them according to his constitutional theory. This study investigated how similar his modified prescriptions to original formulas through database[ancient formula database] analysis. 24 out of 24 Soum prescriptions selected meaningful ingredient herbs from the original formula. A 50% or higher concordance rate compared to the original formulas. There are only 9 treatment prescriptions that cannot be checked in the ancient formula database. A future task will be to reveal the practical meanings of the ingredients Lee Jema adjusted for the Soum constitutional type patients.

• Asian Journal of Innovation and Policy
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• v.10 no.2
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• pp.236-248
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• 2021

The objective of this study is to introduce the urban utility concept that combines urban growth and urban disasters in the aspect of a conceptual theory. While many studies focused on the dollar amount damaged from a disaster, it requires adding not just building damages or human body losses but also the quality of life satisfaction. An issue in measuring the quality of life satisfaction needs to introduce a proper mode quantifying it. This study introduces the urban utility change in measuring the negative impacts of a disaster on urban life, which has been rarely investigated. To identify urban utility, urban flooding that is a cross-sectoral agenda and important to both developed and developing countries was adopted to respond to its increased frequency and damages, encouraging governments to focus on flood control policies. By combining a literature review on urban utility and urban growth, this study defined the urban utility concept as a net benefit of a resident with earnings subtracting housing and commuting costs. The theoretical study also explained that urban utility and its components dynamically change as per urban growth and disasters that even reversely affect urban growth. Because the urban utility can be one of the useful indices to appreciate the relationship between a disaster and urban growth, it is highly expected to apply for similar disaster impacts on urban areas, including COVID-19 and various global warming issues.

• Journal of the Korea Convergence Society
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• v.12 no.5
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• pp.121-126
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• 2021

Based on network agenda-setting theory, this study attempted to analyze media reports about suicide from 2000 to 2020 in order to find solutions for suicide problem in the Korean society. Results showed that top 10 key words in media were suicide, death leap, death, attempt, supposition, discovery, men, pessimism. Those key words were appeared similarly and contunually in the media. In addition, both newspapers and broadcastings had similar reports trend, so it is plausible to consider inter-media agenda setting relations between newspapers and broadcasings.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.5
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• pp.863-872
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• 2021

The main goal of this research is to understand how small and medium enterprises (SMEs) owners in Oman perceive the factors that drive or impede their growth and sustainability. Based on survey data of 395 SMEs in Oman, factor analysis was conducted to check if all the items load as one factor in each of the constructs. The results show that all the items measuring motivators and barriers loaded significantly for the respective scales, with high reliability (Cronbach alpha for Motivators = 0.991 and Barriers = 0.995). Relationships between the demographic factors of entrepreneurs and firm characteristics were tested and it was found that all the four variables: age of the entrepreneur (p = 0.00), qualification of the entrepreneur (p = 0.00), SME sector (p = 0.00), and age of the firm (p = 0.00) have a significant relationship with both the Motivators and the Barriers. The findings of this study could have significant implications for policymakers in Oman and other Middle Eastern countries. Since SMEs face similar problems and are given priority around the world, the findings could be applicable to other countries, as well. The findings also add important results to the empirical literature on SMEs.