• 한국전산유체공학회:학술대회논문집
• /
• 2006.05a
• /
• pp.301-305
• /
• 2006

The Vertical Launching System design is especially complicated by complex flow structure in a plenum with the severe thermal state and high pressure load form the hot exhaust plume. The flow structures are numerically simulated by using the commercial code, CFD-FASTRAN with the axi-symmetrical Navier-Stokes equations. Two different cases are considered; that is, the stationary fire and the moving fire.

• Proceedings of the KIEE Conference
• /
• 2002.07c
• /
• pp.1896-1898
• /
• 2002

In this paper, to developing thermally and mechanically upgraded ones, we dismounted pole transformers used in the fields for over 13 years and conducted aged oil analysis. Also, when the cellulose and aramid papers in test cell were aging with oil at $130^{\circ}C$ for 3000 hours, with the testing period cellulose paper deteriorated more rapidly than the others. For example dielectric strength and dissipation factor of papers deteriorated with aging time. For evaluation of thermal aging characteristics, a mineral oil-immersed transformer was constructed with hybrid insulation system comprised of aramid paper and cellulose insulation. A Hybrid system has economic advantages. Cellulose materials are confined to cooler regions of the transformer winding. And aramid papers are served to insulate contact parts of hot conductors.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2013.02a
• /
• pp.521-521
• /
• 2013

Collective Thomson scattering (CTS) system is being developed in KAERI based on high power gyrotrons. CTS is a promising diagnostic method to measure fast ion distributions and potentially the fusion product alpha particles in magnetically confined plasmas. By utilizing millimeter-waves from high power gyrotrons as a probing beam, spatially and temporally resolved 1-D ion velocity distributions can be obtained from the scattered radiation with less scattering geometrical constraints. The pulse modulation of gyrotrons enables to separate scattering signal from ECE background noises. The feasibility was assessed with the calculation of spectral density functions under the condition of KSTAR plasmas. Further CTS system requirements are also discussed.

• International conference on construction engineering and project management
• /
• 2009.05a
• /
• pp.717-724
• /
• 2009

Most recent programs in and out of the country are related to urban renewal projects. Contemporary project management information systems have been developed was to manage single or multiple projects focusing on their construction phase, and those have limitations to apply to large-scale complicated mega projects. So, this study explain the core concept of decision support modules for iPMIS (Intelligent Program Management Information System) and its major functions to support project owner and participants by introducing ontology in the web environment. This study confined the scope of research to the planning phase of urban environment improvement projects. Ontological logic structure and relation about planning works is essential parts and three functions to implement decision support module are developed.

• Journal of the Korean Society for Precision Engineering
• /
• v.12 no.7
• /
• pp.74-81
• /
• 1995

In this paper, a composite controller cosisted of bandpass feedback controller and LQG/LTR controller is applied to a quarter-car model moving on a randomly profiled road. The LQG/LTR controller is used to achieve a design transfer toop. A bandpass feedback controller is adopted to eliminate the response due to the disturbance, which generally can not be measured, confined within an interested frequence range. The random road profile considered as colored noise is shaped from white noise by use of shaping filter. The performance of the composite control system is compared with that of an LQG/LTR control system.

• Transactions on Electrical and Electronic Materials
• /
• v.5 no.1
• /
• pp.11-14
• /
• 2004

An rf triode magnetron sputtering system is designed and installed its construction in vacuum chamber. In order to calibrate the rf triode magnetron sputtering for thin films deposition processes, the effects of different glow discharge conditions were investigated in terms of the deposition rate measurements. The basic parameters for calibrating experiment in this sputtering system are rf power input, gas pressure, plasma current, and target-to-substrate distance. Because a knowledge of the deposition rate is necessary to control film thickness and to evaluate optimal conditions which are an important consideration in preparing better thin films, the deposition rates of copper as a testing material under the various sputtering conditions are investigated. Furthermore, a triode sputtering system designed in our team is simulated by the SIMION program. As a result, it is sure that the simulation of electron trajectories in the sputtering system is confined directly above the target surface by the force of E${\times}$B field. Finally, some teats with the above 4 different sputtering conditions demonstrate that the deposition rate of rf triode magnetron sputtering is relatively higher than that of the conventional sputtering system. This means that the higher deposition rate is probably caused by a high ion density in the triode and magnetron system. The erosion area of target surface bombarded by Ar ion is sputtered widely on the whole target except on both magnet sides. Therefore, the designed rf triode magnetron sputtering is a powerful deposition system.

• International Journal of Internet, Broadcasting and Communication
• /
• v.16 no.3
• /
• pp.212-220
• /
• 2024

A recently the advancement of society, AI technology has made significant strides, especially in the fields of computer vision and voice recognition. This study introduces a system that leverages these technologies to recognize users through a camera and relay commands within a vehicle based on voice commands. The system uses the YOLO (You Only Look Once) machine learning algorithm, widely used for object and entity recognition, to identify specific users. For voice command recognition, a machine learning model based on spectrogram voice analysis is employed to identify specific commands. This design aims to enhance security and convenience by preventing unauthorized access to vehicles and IoT devices by anyone other than registered users. We converts camera input data into YOLO system inputs to determine if it is a person, Additionally, it collects voice data through a microphone embedded in the device or computer, converting it into time-domain spectrogram data to be used as input for the voice recognition machine learning system. The input camera image data and voice data undergo inference tasks through pre-trained models, enabling the recognition of simple commands within a limited space based on the inference results. This study demonstrates the feasibility of constructing a device management system within a confined space that enhances security and user convenience through a simple real-time system model. Finally our work aims to provide practical solutions in various application fields, such as smart homes and autonomous vehicles.

• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.18 no.5
• /
• pp.191-194
• /
• 2008

We will focus on the horizontal Bridgman growth system to analyze the transport phenomena numerically, because the simple furnace system and the confined growth environment allow for the precise understanding of the transport phenomena in solidification process. In conventional melt growth process, the dopant concentration tends to vary significantly along the crystal. In this work, we propose the modification of crucible geometry for improving the productivity of silicon single-crystal growth by controlling axial specific resistivity distribution. Numerical analysis has been performed to study the transport phenomena of dopant impurities in conventional and proposed Bridgman silicon growth using the finite element method and implicit Euler time integration. It has been demonstrated using mathematical models and by numerical analysis that proposed method is useful for obtaining crystals with superior uniformity along the growth direction at a lower cost than can be obtained by the conventional melt growth process.

• Proceedings of the Korea Inteligent Information System Society Conference
• /
• 2007.05a
• /
• pp.229-238
• /
• 2007

This study was intended to point out the limit of existing digital content-centered studies, or approaches from the viewpoint of the supplier and in the aspect of business profit model and find ways to assess the quality of digital content, considering the characteristics of digital content. For this, the study is to apply value innovation strategy to digital content assessment, to analyze the applicability, and to propose a new and practical framework for digital content assessment method. To this end, this study selected the global No. 1 search service provider Google and local portal site Naver search service. The study on assessment factors by value innovation strategy was based on existing literature, while user-value elements in that respect were confined to information quality, interactivity, communication, interactive storytelling, and usability. This study objectified the relation with the value innovation strategic analysis, through qualitative and quantitative analyses on value elements of search service users.

• Korean Management Science Review
• /
• v.12 no.2
• /
• pp.43-62
• /
• 1995

For a complex scheduling system like time table construction, its optimal solution, if exists, is hard to obtain. In this paper, the scheduling environment is reasonably confined as where objects have their own events competing for better slots on boards, and objects have their own board slot preferences and belong to one or more classes of the society which globally constrains them. Here, two phase method is suggested, where the first phase is human-like preference driven and the second phase is for fine tuning by considering all the factors given. Designed and implemented in our system HI-SCHED are dynamic object switching, temporal-constraint-driven intelligent backtracking, case-based revisions, object-based approach, and so on. Some satisfaction degrees are also defined to measure the usefulness of our method. In addition, look-ahead dynamic object switching is considered, and additional global constraints are introduced and processed. A simple scheme is also used to verify the usefulness of the post processing scheme.