• Journal of Korea Game Society
• /
• v.18 no.1
• /
• pp.27-38
• /
• 2018

Today, the field that actively utilizes HMD, which is a representative implementation device of virtual reality, is game. We have frequently used interface design using metaphor to user interface of HMD based virtual reality game. The purpose of this study is to find out the metaphor types that appear in the game interface of the virtual reality FPS genre of HMD devices, which is a new medium. As a result of research, the metaphor types appearing on multiple interfaces have navigation, predictability-based, familiarizing, and physical world metaphor in terms of information perception and predictability-based and familiarizing metaphor in term of control action. It is considered possible to construct a correct mental model. It is expected that the stability-based metaphor to prevent user mistakes and the presentation metaphor to identify the identity of information space will be needed in the future.

• The Journal of Korean Academy of Prosthodontics
• /
• v.9 no.1
• /
• pp.41-45
• /
• 1969

A major disadvantage of Dental cements is their solubility. So it is very important to measure the exact amount of solubility to select clinically suitable materials. The most common laboratory test for solubility is the measurement of disintegration in distilled water, as outlined in A.D.A. Specifications 8 and 9, In addition to the possible factors influencing the solubility, the experiments were all conducted in compliance with A.D.A. Specifications. The solubility of 2 Zinc Phosphate cements and 1 Silicate cement in time of dissolution, concentration of solute in dissolving medium, and type of dissolving medium were investigated. The following results were obtained. 1. Generally the materials were more soluble in organic acids than in distilled water. 2. The dissolution cements tends be minimized by tests utilizing prolonged storage in the same media. 3. In Acetic acid solution, Zinc Phosphate cements were more soluble than Silicate cement, and in Citric acid solution both were markedly more soluble. 4. Solubility was increased by continually presenting fresh liquid, unsaturated with solute, to the cement-water interface.

• 한국전산유체공학회:학술대회논문집
• /
• 2010.05a
• /
• pp.365-367
• /
• 2010

In this paper, we presented the exact Riemann solver for the air-water two-phase shock tube problems where the strength of the propagated sock wave is moderately weak. The shock tube has a diaphragm in the middle which separates water medium in the left and air medium in the right. By rupturing the diaphragm, various waves such as rarefaction wave, shock wave and contact discontinuity are propagated into water and air. Both fluids are treated as compressible, with the linearized equations of state. We used the isentropic relations for the air and water assuming a weak shock wave. We solved the shock tube problem considering a high pressure in the water and a low pressure in the air. The numerical results cleary showed a left-traveling rarefaction wave in the water, a right-traveling shock wave in the air, and the right-traveling material interface.

• Journal of computational fluids engineering
• /
• v.15 no.3
• /
• pp.73-80
• /
• 2010

In this paper, we present the exact Riemann solver for the compressible liquid-gas two-phase shock tube problems. We hereby consider both isentropic and non-isentropic two-phase flows. The shock tube has a diaphragm in the mid-section which separates the liquid medium on the left and the gas medium on the right. By rupturing the diaphragm, various waves are observed on the phasic field variables such as pressure, density, temperature and void fraction in the form of rarefaction wave, shock wave and material interface (contact discontinuity). Both phases are treated as compressible fluids using the linearized equation of state or the stiffened-gas equation of state. We solve several shock tube problems made of a high/low pressure in the liquid and a low/high pressure in the gas. The wave propagations are well resolved by the exact Riemann solutions.

• Journal of the Korean Society for Industrial and Applied Mathematics
• /
• v.11 no.1
• /
• pp.1-11
• /
• 2007

A linear stability analysis applied to a system consist of a horizontal fluid layer overlying a layer of a porous medium affected by a vertical magnetic field on both layers. Flow in porous medium is assumed to be governed by Darcy's law. The Beavers-Joseph condition is applied at the interface between the two layers. Numerical solutions are obtained for stationary convection case using the method of expansion of Chebyshev polynomials. It is found that the spectral method has a strong ability to solve the multilayered problem and that the magnetic field has a strong effect in his model.

• Journal of Advanced Marine Engineering and Technology
• /
• v.39 no.8
• /
• pp.863-869
• /
• 2015

This study analyzed the offshore plant industry and related regulations such as ISO, IEC, and Norsok Standards to develop an integrated network management system (INMS) capable of both on-site and remote management and configuration of IP-based network equipment in offshore plants. The INMS was designed based on actual specifications and POS plans, and a plan of management was verified through an offshore plant engineering company. Various modules such as PAGA interface modules, CCTV, IP-PBX, and HF-radio communication modules were developed for system implementation. Protocol and data design and screen design were followed by framework development and introduction of the automatic satellite communication function.

• Journal of the Korean Society for Nondestructive Testing
• /
• v.29 no.3
• /
• pp.242-247
• /
• 2009

The ability of time reversal techniques to focus ultrasonic beams on the source location is important in many aspects of ultrasonic nondestructive evaluation. In this paper, we investigate the time reversal beam focusing of ultrasonic array sensors on a defect in layered media. Numerical modeling is performed using the commercially available software which employs a time domain finite difference method. Two different time reversal approaches are considered - the through transmission and the pulse-echo. Linear array sensors composed of N elements of line sources are used for signal reception/excitation, time reversal, and reemission in time reversal processes associated with the scattering source of a side-drilled hole located in the second layer of two layer structure. The simulation results demonstrate the time reversal focusing even with multiple reflections from the interface of layered structure. We examine the focusing resolution that is related to the propagation distance, the size of array sensor and the wavelength.

• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 2004.10a
• /
• pp.357-360
• /
• 2004

Electronic Data Interchange (EDI) between a number of companies goes on increasing on the internet. Although a conventional EDI system reduces business process efforts, time, resources, etc., important information is easily and frequently exposed by well trained hackers and crackers, which inflict a severe loss on the company and even put the company under a crisis. This study integrates the conventional EDI system and Virtual Private Net (VPN) to maximize an overall efficiency of speed and security in data transaction by the level of importance. The EDI system properly interfaced to IPSec and L2TP of VPN allows us to select two modes: the one focuses on a high speed with a low or a medium level security or the other does on a high level security with a low or a medium level speed. Both the company and the end users get a lot of tangible and intangible advantages by integrating the EDI system and VPN.

• Structural Engineering and Mechanics
• /
• v.66 no.1
• /
• pp.113-124
• /
• 2018

In the present paper, we have considered a layered medium of two semi-infinite nonlocal elastic solids with intermediate transversely isotropic magnetothermoelastic solid. The intermediate slab is of uniform thickness with the effects of two temperature, rotation and Hall current and with and without energy dissipation. A plane longitudinal or transverse wave propagating through one of the nonlocal elastic solid half spaces, is made incident upon transversely isotropic slab and it results into various reflected and refracted waves. The amplitude ratios of various reflected and refracted waves are obtained by using appropriate boundary conditions. The effect of nonlocal parameter on the variation of various amplitude ratios with angle of incidence are depicted graphically. Some cases of interest are also deduced.

• Korean Journal of Computational Design and Engineering
• /
• v.14 no.4
• /
• pp.254-260
• /
• 2009

Most commercial PDM (product data management) systems, which have been released recently by overseas famous software vendors, are still expensive and heavy to apply to small and medium enterprises (SMEs). Proposed in this paper are an architecture and functions of collaborative BOM (bill-of-material) management system (cBOM-MS) which supports the internal BOM management by BOM Navigator, provides SMEs with constructing the collaborative BOM via Collaborative BOM Portal, and proposes an interface to extract BOM automatically from commercial CAD systems. In the design of cBOM-MS, BOM Navigator and cBOM Portal are positioned separately to reinforce the information security about product data during product development process.