• Proceedings of the KSR Conference
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• 2009.05b
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• pp.209-214
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• 2009

In this research, an external noise distribution of a HST has been analyzed by using a ray tracing techniques. An aero-dynamic noise generated from a bogie has been considered as a major noise source. Then a distribution of the noise on the outside of the vehicle is calculated using a ray noise technique. The models simulated are two different acoustic fields: an open field and a tunnel. In order to evaluate the noise effects, an exterior structure has been modified by using a different length of skirts. Various application schemes of reducing an environmental noise level will be expected for a HST based on this research.

• Journal of the Korean Society of Industry Convergence
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• v.27 no.1
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• pp.183-193
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• 2024

Recurrent Neural Network technology that learns past patterns and predicts future patterns using technology for recognizing and classifying objects is being applied to various industries, economies, and languages. And research for practical use is making a lot of progress. However, research on the application of Recurrent Neural Networks for evaluating and predicting the safety of mechanical structures is insufficient. Accurate detection of external load applied to the outside is required to evaluate the safety of mechanical structures. Learning of Recurrent Neural Networks for this requires a large amount of load data. This study applied the Gated Recurrent Unit technique to examine the possibility of load learning and investigated the possibility of applying a stacked Auto Encoder as a way to secure load data. In addition, the usefulness of learning mechanical loads was analyzed with the Gated Recurrent Unit technique, and the basic setting of related functions and parameters was proposed to secure accuracy in the recognition and prediction of loads.

• The KIPS Transactions:PartC
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• v.11C no.5
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• pp.683-688
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• 2004

NAT is a very useful IP address translation technique that allows two connected networks using different and incompatible IP address schemes. But it is impractical to use NAT for an application which uses the encrypted IP packet, embedding IP addresses inside of data payloads, to guarantee End-to-End Security such as IPSec. In addition to rewriting the source/destination IP addresses in the packet, NAT must modify IP checksum every time, which could lead to considerable performance decrease of the overall system in the process of the address translation. RSIP is an alternative to solve these disadvantages of NAT and the address shortage problems. Both NAT and RSIP divide networks into inside and outside addressing realms. NAT translates addresses between internal network and external network, but RSIP uses a borrowed external address for outside communications. RSIP server assigns a routable public address to a RSIP client temporarily to communicate with public net-work outside of the private network. In this paper, RSIP gateway for intranet environment is designed and its performance is evaluated. From the results of performance evaluation, we knew that RSIP is operated less sensitive to the data traffic. Also, the experiment shows that RSIP performs better than NAT when the transmission data grows larger.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.9 no.3
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• pp.130-135
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• 2000

In this study the vibration behavior of the stiffened double cylinder was experimently analyzed. Due to the complex structure of the double cylinder the outside cylinder frequency responses to the exciting forces applied on various posi-tions were analyzed by using spectrum analyzer in conjunction with an accelerometer and the natural frequencies were obtained. The technique of time-averaged holographic interferometry is applied to study the vibration characteristics of outside cylinder with stiffening T frame. The experimental data showed that the T frame had salient effect of damping on the testing structure at most of resonances. however the experimental results also revealed interesting phenomenon. At some particular frequencies the T frame. The experimental data showed that the T frame had salient effect of damping on the testing structure at most of resonances. However the experimental results also revealed interesting phenomenon. At some particular frequencies the T frame seemed to behave as a transmitter. In addition it has been successfully demon-started that optical method such as holographic interferometry is well suited for the identification of mode shapes. They can give us a whole-field non-contact measurement instead of the point-wise measurement by accelerometer in classical modal testing.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2008.10a
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• pp.122-125
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• 2008

Even though many researchers studied the foot shape and dimension, those applications lacked. The purpose of this study was to develop insole pattern of elderly women according to footprint. Discrepancy in the classification criteria among of foot parameters complicates attempts for elderly women classification of foot sole. To develop a footprint-based classification technique for the classification of foot sole types by allowing simultaneous use of several parameters. Foot sole data from static standing footprints were recorded from 48 elderly women. The factors of footprint shape were determined. Cluster analysis was applied to obtain individual foot sole classifications. The classification model of foot insole is proposed for a classification of footprint in elderly women. An application of ANOVA, Duncan's analysis, frequency analysis, factor analysis, and cluster analysis have been made to footprint data. In order to make clear foot sole characteristics, the factors of footprint shape have been discussed. The results are as follows. The factors of footprint shape have been classified into four types: foot length, sole slope, outside sole slope, and foot width. The types of foot sole shape have been classified into four types: longed, shortened, outside sloped, and toes sloped.

• Journal of Korean Medicine Rehabilitation
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• v.21 no.2
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• pp.171-188
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• 2011

Objectives : The aim of this study is to analyze the actual investigation and classification of osteopathic manipulation by investigation of the various literature of the inside and outside of the country, and to present the application plan of osteopathy in chuna manual therapy for meridian sinew system. Methods : I referred to the domestic and foreign books about osteopathy and chiropractic. In order to investigate domestic dissertations, I searched 4 Korean medical databases and 4 Korean medical journals of osteopathy. Search terms used were osteopathy, osteopathic, fascia, proprioreceptor, mechanoreceptor, muscle spindle, golgi tendon organ, osteopathic manipulation technics. And I classified all the searched studies into principle and region and etc. In order to investigate foreign dissertations, I search 'NCBI pubmed'. Search terms used were osteopathy, osteopathic technique, osteopathic manipulative technique. Results : 1. Osteopathy do not regard the systems which compose the human body in individual territory, but regard whole. It is diagnosis, prevention and medicine which treats 2. Osteopathic manipulation techniques are classified into direct techniques, indirect techniques, and compound techniques. 3. Osteopathic manipulation techniques are classified into fascia, muscle, ligament-joint in applied region. 4. I could search clinical cases in domestic and foreign study. I found cases about myofascial release technique(MFR), postisometric relaxation(PIR), proprioceptive neuromuscular fascilitation(PNF), muscle energy technique(MET), joint mobilization in domestic studies, and strain-counterstrain technique(SCS), MET, AK in foreign studies. Conclusions : Osteopathic manipulation techniques can be used in diagnosis and treatment of meridian muscle theory, because osteopathy and the oriental medicine have many similarities in theoretical background. So osteopathic manipulation technique can be useful in oriental medicine treatment techniques.

• Nuclear Engineering and Technology
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• v.20 no.3
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• pp.170-178
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• 1988

An automated ultrasonic flaw detection system was developed for thin-walled and short tubes such as Zircaloy-4 tubes used for cladding heavy-water reactor fuel. The system was based on the two channels immersion pulse-echo technique using 14 MHz shear wave and the specially developed helical scanning technique, in which the tube to be tested is only rotated and the small water tank with spherical focus ultrasonic transducers is translated along the tube length. The optimum angle of incidence of ultrasonic beam was 26 degrees, at which the inside and outside surface defects with the same size and direction could be detected with the same sensitivity. The maximum permissible defects in the Zircaloy-4 tubes, i.e., the longitudinal and circumferential v notches with the length of 0.76mm and 0.38mm, respectively and the depth of 0.04 mm on the inside and outside surface, could be easily detected by the system with the inspection speed of about 1 m/min and the very excellent reproducibility. The ratio of signal to noise was greater than 20 dB for the longitudinal defects and 12 dB for the circumferential defects.

• Journal of the Korean Society for Nondestructive Testing
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• v.33 no.6
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• pp.519-523
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• 2013

A steam generator (SG) tube is an important component of a nuclear power plant (NPP). It works as a pressure boundary between the primary and secondary systems. The integrity of a SG tube can be assessed by an eddy current test every outage. The eddy current technique(adopting a bobbin probe) is currently the main technique used to assess the integrity of the tubing of a steam generator. An eddy current signal analyst for steam generator tubes continuously analyzes data over a given period of time. However, there are possibilities that the analyst conducting the test may get tired and cause mistakes, such as: missing indications or not being able to separate a true defect signal from one that is more complicated. This error could lead to confusion and an improper interpretation of the signal analysis. In order to avoid these possibilities, many countries of opted for automated analyses. Axial ODSCC (outside diameter stress corrosion cracking) defects on the tubes of OPR1000 steam generators have been found on the tube that are in contract with tube support plates. In this study, automated analysis software called CDS (computer data screening) made by Zetec was used. This paper will discuss the results of introducing an automated analysis system for an axial ODSCC on the tubes of an OPR1000 steam generator.

• Journal of Biomedical Engineering Research
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• v.30 no.4
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• pp.271-278
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• 2009

Recently, robot research and development was interesting the inside and outside of the country. Medical robot surgery showed diverse advantages according to advanced technical robot research. Also the academic society, research institute and industry showed concerning to the medical robot system. There is a growing need to introduce medical research for aging society. The surgical landscape is quickly changing because of the major driving force of robotics. Robot system and biomedical engineering research as defined a new engine of development show present ways of future revitalization of medical robot system. Medical robot system will be even more utilized when we keeps trying to combine high biomedical technique, IT research, and robot technique. In this review article, we begin with a short historical review of medical robotics, followed by an overview of clinical applications where robots have been applied.

• Journal of Biomedical Engineering Research
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• v.25 no.3
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• pp.183-188
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• 2004

Magnetic resonance current density imaging (MRCDI) is a useful method for measuring electrical current density distribution inside an object. To avoid object rotations during the conventional MRCDI scans, we have reconstructed current density component images by applying a spatial filter to the magnetic field data measured both inside and outside the object. To measure the magnetic field outside the object with MRI, we immersed the object in a water tank. To evaluate accuracy of the current density imaging, we have made a conductivity phantom with a corresponding finite element method model. We have compared the experimentally obtained current density images with the ones calculated by the finite element method. The average errors of the reconstructed current density images were 6.6 ∼ 45.4 ％ when the injected currents were 1 ∼ 24 mA. We expect that the current density component imaging technique can be used in diverse biomedical applications such as electrical therapy system developments and biological electrical safety analysis.