• International Journal of Vascular Biomedical Engineering
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• v.3 no.2
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• pp.17-24
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• 2005

The main purpose of our study is to propose a new methodology to develop the multi-parametric measure including linear and nonlinear measures of heart rate variability diagnosing cardiovascular disease. We recorded electrocardiogram for three recumbent postures; the supine, left lateral, and right lateral postures. Twenty control subjects (age: $56.70{\pm}9.23$ years), 51 patients with angina pectoris (age: $59.98{\pm}8.41$ years) and 13 patients with acute coronary syndrome (age: $59.08{\pm}9.86$ years) participated in this study. To develop the multi-parametric measure of HRV, we used the multiple discriminant analysis method among statistical techniques. As a result, the multiple discriminant analysis gave 75.0% of goodness of fit. When the linear and nonlinear measures of HRV are individually used as a clinical tool to diagnose cardiac autonomic function, there is quite a possibility that the wrong results will be obtained due to each measure has different characteristics. Although our study is a preliminary one, we suggest that the multi-parametric measure, which takes into consideration the whole possible linear and nonlinear measures of HRV, may be helpful to diagnose the cardiovascular disease as a diagnostic supplementary tool.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2000.05a
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• pp.252-256
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• 2000

In this paper, WBI tool is designed and implemented to meet the level teaming requirements. The system is composed of management part for teacher and user part for students. The management part supports the teacher to upload the lecture notes and the testing sheets, and to evaluate the testing results. The students can study the lecture notes and examine the online tests based on their teaming level. The students can evaluate their achievement by themselves after test and can study deep learning or supplementary learning. By applying the level teaming concept, the implemented can provide the interest to the students and enhance the degree of achievement.

• Korean System Dynamics Review
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• v.14 no.1
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• pp.55-68
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• 2013

It is necessary to evaluate the greenhouse gases (GHGs) reduction policy by central and regional governments to set up the suitable GHG emissions measures. Quantitative, qualitative and synthetic methods have been adopted by previous researches to estimate GHG reduction policy. However, these methods mostly focused on the results of the reduction policy, rather than understanding and fixing the integrated structures of GHG emissions. In this research, System Dynamics(SD) was applied to 1 million green homes program, self-carfree-day system and carbon point program. The results showed that SD analyses could be appliable for the estimation of GHG reduction policy by developing the feedback loops and dynamic simulation model. SD can be consider as a supplementary tool to estimate the GHG reduction policies through the recognition of the structure in complex real system.

• Journal of Electrical Engineering and Technology
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• v.6 no.1
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• pp.42-47
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• 2011

Automatic generation control (AGC) is an important function for load frequency control, which is being implemented in Energy Management System (EMS). A key feature of AGC is to back up governors to enhance the performance of frequency control. The governor regulates system frequency in several to ten seconds, while the droop control concept results in steady-state control error. AGC is a supplementary tool for compensation of the steady-state error caused by the droop setting of the governors. As the AGC target is delivered to each generator as an open loop control target, the generator output is not guaranteed to follow the AGC target. In this paper, we introduce generating unit controller (GUC) control block, which has the purpose of enabling the generator output to track the AGC target while maintaining the governor performance. We also address the tuning methods of GUC for better performance of AGC in the Korea Energy Management System (K-EMS).

• Journal of the Korean Operations Research and Management Science Society
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• v.12 no.1
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• pp.111-111
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• 1987

With the increasing interest of reducing process variation, statistical process control has served the pivotal tool in most industrial quality programs. In this study, system analyses have been performed associated with a cost incorporated version of a process control, a quadratic loss-based X over bar control chart model. Specifically, two issues, the capital/research investments for improvement of a system and the precision of a parameter estimation, have been addressed and discussed. Through the analysis of experimental results, we show that process variability is seen to be one of the most important sources of loss and quality improvement efforts should be directed to reduce this variability. We further derive the results that, even if the optimal designs may be sensitive, the model appears to be robust with regard to misspecification of parameters. The approach and discussion taken in this study provide a meaningful guide for proper process control. We conclude this study with providing general comments.

• Korean Management Science Review
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• v.12 no.1
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• pp.111-124
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• 1995

With the increasing interest of reducing process variation, statistical process control has served the pivotal tool in most industrial quality programs. In this study, system analyses have been performed associated with a cost incorporated version of a process control, a quadratic loss-based X over bar control chart model. Specifically, two issues, the capital/research investments for improvement of a system and the precision of a parameter estimation, have been addressed and discussed. Through the analysis of experimental results, we show that process variability is seen to be one of the most important sources of loss and quality improvement efforts should be directed to reduce this variability. We further derive the results that, even if the optimal designs may be sensitive, the model appears to be robust with regard to misspecification of parameters. The approach and discussion taken in this study provide a meaningful guide for proper process control. We conclude this study with providing general comments.

• Journal of Information Technology Applications and Management
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• v.16 no.4
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• pp.263-283
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• 2009

Although some CASE tools supported conceptual data design, they required for users too much preliminary knowledge to learn how to use and handle them. In addition, in a number of studies on conceptual data design with natural language, they claimed passive participation for users with conforming to messages predefined by CASE tools. As an alternative to these traditional CASE tools, we proposed an ERD formulator for automated data design tool, called ERDF, so that even ordinary users, not necessarily data modeler, are capable of formulating ERD on business requirements by use of ERDF. We, first of all, introduced NSM as the standard methodology. We also designed the structure of ERDF including main controller, input controller, operation controller, regulation controller, schema controller, and output controller. We then defined conceptual domains and basic operations to lay down schema operations as well as sentence rules to handle input sentence in natural language. To get an ERD that is faithful to business requirements, we laid out supplementary design for dialogue and confirmation of soundness and completion.

• Speech Sciences
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• v.7 no.1
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• pp.89-96
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• 2000

Examination of the vibrations of the vocal fold is very important in patients with voice changes. The newly developed videokymography (VKG) takes images in real time and records irregular vibrations of the vocal fold. However, there are few data on VKG findings. We studied VKG to evaluate the vibratory characteristics of the vocal fold in benign vocal fold lesions. Unique vibratory patterns, blurred demarcation of the mucosal propagation, decreased margin amplitudes, asymmetry in phase or amplitude, and a level difference of the contact site were observed in each benign vocal-fold lesion. We conclude that each type of laryngeal lesion has specific characteristic which are revealed by VKG examination, these parameters can be quantified and used to objectively evaluate VKG findings. Based on these results, VKG can be used as a supplementary diagnostic tool.

• Steel and Composite Structures
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• v.1 no.1
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• pp.75-96
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• 2001

Actual buckling curves are always characterised by the erosion of ideal buckling curves. In case of compact sections this erosion is due to the imperfections, while for thin-walled members, a supplementary erosion is induced by the phenomenon of coupled instabilities. The ECBL approach- Erosion of Critical Bifurcation Load - represents a practical and convenient tool to characterise the instability behaviour of thin-walled members. The present state-of-art paper describes the theoretical background of this method and the applications to cold-formed steel sections in compression and bending. Special attention is paid to the evaluation methods of erosion coefficient and to their validation. The ECBL approach can be also used to the plastic-elastic interactive buckling of thin-walled members, and the paper provides significant results on this line.

• Annals of Clinical Neurophysiology
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• v.8 no.2
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• pp.174-178
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• 2006

The diagnosis of peripheral neuropathy had been performed by electrophysiologic studies and neurologic examination. However, Magnetic Resonance Imaging (MRI) has recently been proposed as a supplementary tool for its diagnosis. A 55-year-old woman presented with back pain and painful proximal weakness of the right leg. Neurologic examination and electrophysiologic studies suggested an upper lumbar plexopathy. MRI disclosed the signal change in lumbar plexus with the atrophy of the innervating muscles. We report a patient with idiopathic lumbar plexopathy confirmed by MRI.