• Journal of Advanced Navigation Technology
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• v.15 no.2
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• pp.326-333
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• 2011

In the present study, we measured the performance (accuracy and reaction time) of the user in the virtual environment with see-through Head-Mounted Display system that includes 3D sound generated through Head-Related Transfer Function (HRTF) to investigate the feasibility of auditory display for a certain object's spatial information. To sum up the results of two experiments, when presenting location information of the object with 3D sound, it is desirable that information arrangement from the user should be an orthogonal pattern which is located with right angle, not a diagonal pattern. Like these results propose that spatial information presentation with 3D sound make the optimal object arrangement of virtual environment possible.

• Journal of the Korean Society of Propulsion Engineers
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• v.5 no.3
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• pp.41-51
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• 2001

Combustion characteristics of a KSR-III liquid rocket engine with split-triplet (F-O-O-F) type injector elements are investigated numerically from the viewpoints of engine performance and combustion flowfield. To evaluate numerical analysis of liquid rocket engine with radial type injector arrangement, 2-D axisymmetric and 3-D calculations are carried out and the prediction of engine performance for design and off-design conditions is in a good agreement with hot-firing tests. According to 2-D axisymmetric and 3-D calculations, the prediction error is 3∼5 % from the standpoint of performance. Numerical results of combustion characteristics calculated through 3-D analysis agree well with hot-firing tests qualitatively at injector plate. Decreasing impinging angle and changing radial type injector arrangement to H type injector arrangement reduce effectively local high-temperature region. Also, it is examined that those affect the performance seriously. In conclusion, it is revealed that both injector arrangement and impinging angle are critical parameters to affect the performance and combustion characteristics of the liquid rocket engine.

• Journal of the Society of Naval Architects of Korea
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• v.52 no.4
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• pp.283-289
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• 2015

RGT(Riser Guide Tube) is a part of mooring on the bottom of a turret system to be connected with a production riser, and DBSC(Diverless Bend Stiffener Connector) is a latching component between them. In this paper, appropriate lug arrangement is decided mathematically for the case that a DBSC is lifted and installed on a RGT under the water while FPSO is under construction. Considering asymmetric arrangement & position of RGT and initial lug position, additional lug positions are determined by using an optimization method. The modified installation scheme with new lug points is investigated with a lifting simulation system, SIMSON. The simulation result shows that the installation of DBSC on RGT under the given conditions is quite feasible; therefore the mathematical method is proven to be appropriate.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.11
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• pp.17-23
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• 2021

A cyclone is a dust-separating mechanism that works on the principle of centrifugal force. The performance of a cyclone is evaluated using pressure loss and collection efficiency. A multi-cyclone arrangement is used to improve the collection efficiency within a limited area. In this study, experiments and numerical analyses were conducted on a dual arrangement of mini-hydrocyclone separators, which was fabricated using 3D printing. The experiment was performed at an inlet flow rate of 0.7 m/s, and alumina powder with a particle size of 0.5, 15, and 50 ㎛. ANSYS FLUENT, was used for the numerical analysis. The reliability of the numerical analysis was verified through a comparison with the experimental results. The errors in the experiment and numerical analysis were confirmed to be 2% at the outlet flow rate.

• Proceedings of the Optical Society of Korea Conference
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• 1990.02a
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• pp.131-135
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• 1990

The combined technique of holographic interferometry and speckle photography, so called holospeckle interferometry, has been attention for the measurement of 3-D displacements. This new technique enables the researcher to obtain information of in plane and out-of plane displacements from one photographic plate. There is room for further development of special optical arrangement in order to apply holospeckle interferometry in specific field. In this study, the enlarged fringe pattern was obtained by specifical optical arrangement.

• Journal of the Korean Society of Clothing and Textiles
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• v.46 no.2
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• pp.321-330
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• 2022

This study analyzed the difference between 2D image and 3D virtual clothing images based on stripe arrangement to obtain fundamental data for slim appearance. First, the slimming effect according to the three types of stripe ratio was examined. Subsequently, the slimming effects of seven types of one-piece dress designs according to the stripe location were analyzed. Subjective ranking was evaluated. The width items and radius of curvature were measured for the image's respective parts. Consequently, in 2D image and 3D virtual clothing images, the one with the narrowest stripe ratio was evaluated as the slimmest; however, the conditions for the slimming effect were different. In the seven one-piece dress designs, a difference was apparent in the ranking of the 2D image and 3D virtual clothing images. In the 3D virtual clothing image, arranging the stripes on the entire garment proved inefficient. The stripes were curved according to the curvature of the human body, creating an optical illusion that differed from that of the 2D image.

• International Journal of Naval Architecture and Ocean Engineering
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• v.8 no.6
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• pp.537-553
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• 2016

This paper addresses the safety of two-row tank design by performing the extensive sloshing model tests. Owing to the uncertainties entangled with the scale law transforming the measured impact pressure up to the full scale one, so called comparative approach was taken to derive the design sloshing load. The target design vessel was chosen as 230 K LNG-FPSO with tow-row tank arrangement and the reference vessel as 138 K conventional LNG carrier, which has past track record without any significant failure due to sloshing loads. Starting with the site-specific metocean data, ship motion analysis was carried out with 3D diffraction-radiation program, then the obtained ship motion data was used as 6DOF tank excitation for subsequent sloshing model test and analysis. The statistical analysis was carried out with obtained peak data and the long-term sloshing load was determined out of it. It was concluded that the normalized sloshing impact pressure on 230 K LNG-FPSO with two-row tank arrangement is higher than that of convectional LNG carrier, hence requires the use of reinforced cargo containment system for the sake of failure-free operation without filling limitation.

• Journal of Advanced Marine Engineering and Technology
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• v.25 no.4
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• pp.857-868
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• 2001

The aerodynamic forces and wake structures of the non-rotating downstream cylinder which is located behind the spinning upstream cylinder in tandem and staggered arrangement have been investigated by experimental method at Re= $1.32{\times}10^4$. The measurements of wake flow and pressure distributions of downstream cylinder are carried out in various spin parameters by combination of both longitudinal spacing rations L/d=1.5, 3.0, 4.5 and transverse spacing ratios T/d =0.0, -0.5, 0.5. For the present experiment, it has been found that the spin parameter of spinning upstream cylinder affect more easily the downstream cylinder in tandem arrangement than that in staggered arrangement.

• Proceedings of the Korea Multimedia Society Conference
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• 2003.11b
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• pp.651-655
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• 2003

본 논문에서는 맞춤 가구 제작 및 제작된 가구의 배치를 위한 효율적이면서도 사용하기 용이한 3D Visual 디스플레이 시스템을 개발하고자 한다. AutoCAD로 만들어진 평면파일(*.dxf) 그리고 3D 제작툴로 만들어진 오브젝트 파일(*.3ds)을 이용하여 현실감 있도록 시뮬레이션 하는 것을 목표로 한다. 2D로 제작된 AutoCAD 평면 설계 파일을 이용하여 평면 파일을 3D 투시도로 변환하고 3DS파일로 구축한 객체들을 배치한 뒤 텍스처매핑, 렌더링 등을 구현하여 최대한 현실감을 낼 수 있도록 개발한다.

• Journal of Korean Society of Archives and Records Management
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• v.16 no.3
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• pp.179-207
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• 2016

This study suggested the necessity of the management of R & D management records produced from government-supported science research institutes (the so-called "gwagichulyeon") and of a record management manual (item). As such, it gathered rules with regard to record management, conducted a survey, and interviewed general R & D managers. As a result of the research, the ratio of the arrangement of R & D managers to R & D management departments is 100%; however, the ratio of the arrangement of record managers is 33.3%-50%, and the ratio of the arrangement of record management departments is 23.1%, which was poor. The enactment ratio of record management rules is 26.4%, and 73.7% of institutes has managed their records under the provision only of document management rules or only of office management rules. R & D management records has been collected according to an institute's capability without a prescribed collection scope, and the conditions with regard to the omission, damage, and loss of records were poor. There are institutes that did not comprehend the production status of R & D management records. Thus, as a response, this study suggested a record management manual (item) established for the arrangement duties of record managers and record management departments as well as for notifications on the status of R & D management records. In addition, this study produced a standardized collection scope and described how to manage R & D management records.