• Journal of Advanced Marine Engineering and Technology
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• v.32 no.8
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• pp.1201-1207
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• 2008

Numerical analysis information will be very useful to improve fluid system. General information about an internal gas flow is presented by numerical analysis approach. Relating with hydrogen compressing system, which have an important role in hydrogen energy utilization, this should be a useful tool to observe the flow quickly and clearly. Flow characteristic analysis, including pressure and turbulence kinetic energy distribution of hydrogen gas coming to the cylinder of a reciprocating compressor are presented in this paper. Suction-passage model is designed based on real model of hydrogen compressor. Pressure boundary conditions are applied considering the real condition of operating system. The result shows pressure and turbulence kinetic energy are not distributed uniformly along the passage of the Hydrogen system. Path line or particles tracks help to demonstrate flow characteristics inside the passage. The existence of vortices and flow direction can be precisely predicted. Based on this result, the design improvement, such as reducing the varying flow parameters and flow reorientation should be done. Consequently, development of the better hydrogen compressing system will be achieved.

• Journal of the Korea Society of Computer and Information
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• v.7 no.4
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• pp.33-39
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• 2002

The present so many systems are used by evolution of Program to expel DNC(Direct Numerical Control) Network Infra for many CNC Controller. However, these systems is an inefficiency side in case of mutual connection at a long distance between Server Computer and Machining center Also, the machining center have so many controversial points in data transmission-receiver from the NC data server. So, this thesis well constructed the remote control system from CNC(Computer Numerical Control) Controller to CAD/CAM Server Computer. This system have some kinds of merits. Firstly. the machining center's user can easily use the saved NC data transmission from the CAD/CAM Server Secondly, the remote control is possible without the mutual conversation between the CAD/CAM Server and the machining center.

• Journal of Korea Society of Digital Industry and Information Management
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• v.11 no.1
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• pp.9-18
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• 2015

Numerical analysis of PSC box bridge bearings for high speed KTX train vehicles has been carried out as a virtual simulation for Ubiquitous Technology. Improved numerical models of bridge, vehicle and interaction between bridge and train are considered, where bending and torsional modes are provided, whereas the exist UIC code is applied by the simplified HL loading. Dynamic and static analysed results are compared to get Dynamic Amplification Factors (D. A. F.) for maximum deflections and bending stresses up to running speed of 500 km/h. Equation from the regression analysis for the D. A. F. is presented. Sliding distance of the bearings for various KTX running speeds is compared with maximum and accumulated distances by the dynamic behaviors of PSC box bridge. Dynamic and static simulated sliding distances of the bearings according to the KTX running speed are proved as a major parameter in spite of the specifications of AASHTO and EN1337-2 focused on the distance by temperature variations.

• Journal of Power System Engineering
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• v.13 no.3
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• pp.27-32
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• 2009

Numerical analysis information of a complex discharge-passage will be very useful to improve hydrogen compression system. General information about an internal gas flow is presented by numerical analysis approach. Relating with hydrogen compressing system, which have an important role in hydrogen energy utilization, this should be a useful tool to observe the flow quickly and clearly. Flow characteristic analysis, including pressure and turbulence kinetic energy distribution of hydrogen gas from cylinder going to the chamber of a reciprocating compressor are presented in this paper. Discharge-passage model is designed based on real model of hydrogen compressor. Pressure boundary conditions are applied considering the real condition of operating system. The result shows pressure and turbulence kinetic energy are not distributed uniformly along the passage of the hydrogen compressing system. Path line or particles tracks help to demonstrate flow characteristics inside the passage. The existence of vortices and flow direction can be precisely predicted. Based on this result, the design improvement should be done. Consequently, development of the better hydrogen compressing system will be achieved.

• Korean Journal of Optics and Photonics
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• v.20 no.6
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• pp.375-380
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• 2009

The scattering of a normally incident monochromatic light by optically active concentric double cylinders is studied by using a numerical method. A numerical code is developed on the basis of the analytical solutions, and the angular distributions of the intensity and the polarization of the scattered light are computed for some specific cases. The numerical code can be used to non-invasively determine the size, structure, and composition of a double cylinder with high accuracy by measuring the angular distribution of the scattered light by an experiment.

• Fashion, Industry and Education
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• v.15 no.2
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• pp.1-10
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• 2017

The purposes of this study were to explore (1) how fit reviews differ among height groups and (2) how overall numerical ratings differ depending on height groups and ifferent types of fit reviews. Content analysis was used to analyze systematically sampled online consumer reviews (OCRs) of formalwear dresses rented online. In part 1, 201 OCRs were analyzed to develop the coding scheme, which included three aspects of fit (physical, aesthetic, and functional), valence (negative, neutral, positive), and overall numerical rating. In part 2, 600 OCRs were coded and statistically analyzed. Differences in frequency were not found among height groups for any types of mentions (negative, neutral, and positive) in terms of the three aspects of fit in the OCRs. Differences in overall mean ratings were not found among height groups. Interestingly, valence of each aspect of fit reviews affected mean numeric ratings. This study is new in examining relationships among textual information (i.e., fit reviews), numerical information (i.e., numerical rating), and reviewer's characteristic (i.e., height). The results of this study offered practical implications for etailers and marketers that they should pay attention to the three aspects of fit reviews and monitor garments with negative fit evaluations for lower ratings. They may attempt to increase ratings by providing customers recommendations to get a better fit.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 1999.11a
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• pp.395-400
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• 1999

At present, some evolutional system has been used to promote the efficiency of the DNC(Direct Numerical Control) Controller. However, these are many inconvenience to this operator because it lacks harmony in interaction between the computer and the NC(Numerical Control). Also, there are some controversial poults when data error occurs at the Data Input/output. According1y, this thesis explores a new Data Remote Control System. In this study, the NC Controller of the DNC network has to Bet full data by removing data error in this system. In this system, the main merits are easy manufacturing and the convenience of Data Input/output. That is, remote control of the NC machine tool is possible without mutual interaction between the computer and itself.

• Journal of the Society of Disaster Information
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• v.13 no.3
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• pp.286-295
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• 2017

In this study, it is compared various coefficients of subgrade reaction for application of numerical analysis based on measured data by using various theories and empirical formula. The ratio of the maximum and minimum value is 6.80 at the top of wall but it is 1.06 at the maximum displacement point depends on change of calculated coefficient of subgrade reaction. The data of displacement were generally similar considering an increment of a coefficient of subgrade reaction. And the results of comparison of the displacement at the maximum displacement point by numerical analysis and measured data show similar displacement shape.

• The Journal of the Korea institute of electronic communication sciences
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• v.14 no.5
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• pp.985-990
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• 2019

In subjects dealing with when historically important events took place, the application of memory laws can enhance the educational effectiveness. Methods to increase memory rate by applying additional information such as dots, lines, bars, etc. are being studied in numerical memory-based studies. This study proposes a method of applying the long-term memory mechanism that was lacking in the previous study. This is a mechanism that corrects the error data entered by user's mistake, and tries to increase the memory rate by giving a memorable effect. To this end, we propose the unique processes that are carried out in the mobile environments and we implement and evaluate the error correction numerical algorithms.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.31 no.3
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• pp.146-157
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• 2019

Recently, the importance of highly accurate bathymetric data is greatly emphasized by the increased use of the ocean numerical models and research results in major areas such as ocean forecasting and natural disaster. There are domestic bathymetric data mainly used in ocean numerical models of Choi et al.(2002) and Seo (2008), but the production year is old and the data was created on the basis of nautical charts. Nautical charts are made for the purpose of navigation and based on the minimum depth from bathymetric data, so there is a limitation to reproduce the actual submarine topography. Korea Hydrographic and Oceanographic Agency (KHOA) produces nautical charts every year through continuous bathymetric survey, but no bathymetric data for numerical models have been produced. In this study, using the raw bathymetric survey data, we built an exclusive bathymetric dataset (BADA Ver.1) for ocean numerical models and compared it with published bathymetric data.