• Journal of the Society of Naval Architects of Korea
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• v.31 no.2
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• pp.29-37
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• 1994

In this paper the modelling procedure and analysis technique for the prediction of accurate critical speeds of marine propeller shafts are suggested. As a solution method the transfer matrix method is employed to calculate the critical speeds, which are correspond to natural frequencies of the shaft in lateral vibration, and whirling responses. Furthermore, in order to check the validity of the simple prediction formulae, such as Jasper's formula and Panagopulos's formula, numerical calculations were performed. From the numerical results it was found that the critical speed of the propeller shaft is sensitive to the position and the supporting conditions of journal bearings.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.8 no.2
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• pp.133-138
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• 2014

In this paper, a simple but efficient gait recognition method using spatial-temporal silhouette analysis is proposed. For each image sequence, a background subtraction algorithm and a PBAS(pixel based adaptive segmenter) procedure are first used to segment the moving silhouettes of a walking figure. Then, to identify people, the step count and stride length of walking figure is obtained in silhouette images. Experimental results on a CASIA dataset including 124 subjects demonstrate the validity of the proposed method. Also, the proposed system are believed to have a sufficient feasibility for the application to gait recognition.

• YAKHAK HOEJI
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• v.13 no.2_3
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• pp.84-87
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• 1969

Microanalysis of organic sulfur compounds by means of combining thin layer chromatography and oxygen combustion flask method was attempted. The following procedure was found to be very simple and to give accurate results. The mixture of sulfa drugs was separated with T.L.C., and it was burned in a flask filled with oxygen, and the gas formed was absorbed in a dilute solution of sodium hydroxide. The solution was neuralized with hydrochloric acid and heated in a water bath. The sulfate ion formed was then treated with barium chromate solution and its absorbancy at 370 m.mu. was measured.

• The Transactions of the Korean Institute of Power Electronics
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• v.23 no.6
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• pp.403-407
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• 2018

This study proposes a predictive direct power control method in a modular multilevel converter (MMC) high-voltage direct-current (HVDC) system. The conventional proportional integral (PI)-based control method uses a cascaded connection and requires an optimal gain selection procedure and additional decoupling scheme. However, the proposed control method has a simple structure for active/reactive power control due to the direct power control scheme and exhibits a fast dynamic response by predicting the future status of system variables and considering time delay. The effectiveness of the proposed method is verified by simulation results.

• Journal of Korean Foot and Ankle Society
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• v.22 no.3
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• pp.127-130
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• 2018

A 3rd degree burn on the heel including the Achilles tendon is vulnerable and requires active treatment to improve the functional outcomes. Previously, there have been a few treatments on severe burns, such as amputation, debridement or simple skin graft. The cooperative technique of an anterior lateral thigh flap with Achilles tendon reconstruction can be an innovative procedure that preserves the major arteries. The authors review a case and report the clinical outcome.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2019.06a
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• pp.163-165
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• 2019

The task of image denoising is gaining popularity in the computer vision research field. Its main objective of restoring the sharp image from given noisy input is demanded in all image processing procedure. In this work, we treat the process of residual hair removal on faces images similar to the task of image denoising. In particular, our method removes the residual hair that presents on the frontal or profile face images and in-paints it with the relevant skin color. To achieve this objective, we employ a deep neural network that able to perform both tasks in one time. Furthermore, simple technic of residual hair color augmentation is introduced to increase the number of training data. This approach is beneficial for improving the robustness of the network. Finally, we show that the experimental results demonstrate the superiority of our network in both quantitative and qualitative performances.

• Journal of Aerospace System Engineering
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• v.15 no.4
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• pp.40-46
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• 2021

At launch, satellites are exposed to various types of structural loads, such as quasi-static loads, sinusoidal vibrations, acoustic/random vibrations, and shocks. The launch environment test is aimed at verifying the structural stability of the test object against the launch environment. Various types of launch environments are simulated by simple vibration, acoustic, and shock tests considering possible test conditions in ground. However, the difference between the launch environment and the test environment is one of the causes of excessive testing. To prevent overtesting, a notching technique that adjusts the frequency range and the input load considering the design load is applied. For notching, specific procedures are established considering the satellite development concept, selected launch vehicle, higher system requirements, and test target level. In this study, the notching method, established procedure, and development of a notching toolkit for efficient testing are described.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.1364-1369
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• 2009

The building construction projects include a variety of risk factors due to uncertainties. To succeed in the projects, it is important how risks are managed. Risk management is composed of identification, analysis and response. Especially, the risk analysis is important to objectively calculate significance of risk factors. This paper evaluates a method to find priorities of risks using the AHP(Analytic Hierarchy Process). The method has some defects; (1) the consistency becomes weak as the number of pair-wise compared risks is large, and (2) the input and output procedures are complex when risks are added to or removed from a risk database. Thus the paper adopt the PROMETHEE(Preference Ranking Organization METHod Enrichment Evaluations) analysis process which is able to overcome the limitation of the AHP restricted to 9 risk factors. The PROMETHEE method makes the procedure of risk analysis simple, when the risk factors pull out and put in the risk database. The purpose of this study is to prove the possibility of the PROMETHEE analysis process by being compared with AHP.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.150.3-151
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• 2003

To analyze the genome of Cucumber mosaic virus(CMV) in pepper, we developed a new extraction method for double-stranded RNA(dsRNA). To isolate the dsRNA, 0.1g of pepper leaves homogenized with 1ml of 5${\times}$EXB extraction buffer[0.5M glycin, 0.5M NaCl, 5mM EDTA(pH9.0/NaOH), 10％ Sodium N-lauryl salcosinate(NLS), 10％ Sodium dodecylsulfate(SDS)] and purified with the 1/4 volume of phenol： chloroform： isoamylalcohol(25：24：1). dsRNAs from the aqueous phase was precipitated with isopropanol. This procedure was able to detect a minimal amount of dsRNA from CMV infected plant tissue and to distinguish different CMV satellite RNAs by polyacrylamide gel electrophoresis(PAGE). Moreover, this method can be applied CMV infected in pepper or Rice dwarf virus (RDV) infected rice.

• Medical Lasers
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• v.8 no.2
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• pp.84-86
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• 2019

Pyriform sinus cyst is a rare disease. This disease can be found by chance or appear as lymph nodes with cancer, infections, shortness of breath, or airway compromise, and can be an unusual cause of dysphonia. This paper presents a case of a pyriform sinus cyst in the pharyngeal wall of the left pyriform sinus, which presented as neck discomfort in a 63-year-old female. The plan was to remove this cyst with a transoral CO₂ laser because a CO₂ laser is a useful tool for removing cysts without bleeding and consuming time. The excision was performed successfully. Transoral laser pyriform sinus cyst excision is a simple, safe, and effective method for the treatment of pyriform sinus cysts. This procedure is likely to be used as a selective treatment when managing this condition.