• Journal of the Korea Society of Computer and Information
• /
• v.18 no.11
• /
• pp.145-151
• /
• 2013

This research is to suggest a method for investigating car number plates among the information managed in parking facilities. The investigation of car number plate is generally used to know how long vehicles are parked. Also, it can provide the information about the parking turnover rate and the mean parking duration of parked vehicles. This research performs the investigation using cameras at a distance of time. That is, the given distance of time from cameras is assigned to each parked vehicle, and then it can find the mean parking time of parked vehicles. Also, it can check the parking turnover rate of parked vehicles at a space unit of parking lot in an hour. The information such as the mean parked duration and the parking turnover rate of parked vehicles taken from this method is helpful to find and understand the inefficient use of parking facilities. With this suggested method, this research attempted to check the mean parking duration and the parking turnover rate of parked vehicles.

• Journal of the Korean Institute of Gas
• /
• v.25 no.5
• /
• pp.88-96
• /
• 2021

Advanced Internet of Things (IoT) technology is being used in various ways for the safety of the energy industry. At the center of safety measures, drones play various roles on behalf of humans. Drones are playing a role in reaching places that are difficult to reach due to large-scale facilities and space restrictions that are difficult for humans to inspect. In this study, the accuracy and completeness of movement of dangerous facilities were tested using drone images, and it was confirmed that the movement recognition accuracy was 100%, the average data analysis accuracy was 95.8699%, and the average completeness was 100%. Based on the experimental results, a future-oriented facility risk analysis system combined with ICT technology was implemented and presented. Additional experiments with diversified conditions are required in the future, and ICT convergence analysis system implementation is required.

• Journal of Broadcast Engineering
• /
• v.26 no.5
• /
• pp.643-651
• /
• 2021

Most people acquire information visually. Screens of computers, smart phones, etc. constantly stimulate people's eyes, increasing fatigue. In this social phenomenon, the realistic and rich sound of the 21st century's state-of-art sound system can affect people's bodies and minds in various ways. Through sound, human beings are given space to calm and observe themselves. The purpose of this paper is to introduce immersive yoga training based on 3D sound conducted together by ALgruppe & Rory's PranaLab and to promote the understanding of immersive audio system. As a result, people, experienced immersive yoga, not only enjoy the effect of sound, but also receive a powerful energy that gives them a sense of inner self-awareness. This is a response to multidisciplinary exchange required by the knowledge of modern society, and at the same time, informs the possibility of new cultural contents.

• Nuclear Engineering and Technology
• /
• v.53 no.6
• /
• pp.1769-1785
• /
• 2021

The Integral Pressurized Water Reactors (IPWRs) as the innovative advanced and generation-III + reactors are under study and developments in a lot of countries. This paper is aimed at the thermal hydraulic study of the hot and average fuel sub-channel in a Generation III + IPWR by loose external coupling to the neutronic simulation. The power produced in fuel pins is calculated by the neutronic simulation via MCNPX2.6 then fuel and coolant temperature changes along fuel sub-channels evaluated by computational fluid dynamic thermal hydraulic calculation through an iterative coupling. The relative power densities along the fuel pin in hot and average fuel sub-channel are calculated in sixteen equal divisions. The highest centerline temperature of the hottest and the average fuel pin are calculated as 633 K (359.85 ℃) and 596 K (322.85 ℃), respectively. The coolant enters the sub-channel with a temperature of 557.15 K (284 ℃) and leaves the hot sub-channel and the average sub-channel with a temperature of 596 K (322.85 ℃) and 579 K (305.85 ℃), respectively. It is shown that the spacer grids result in the enhancement of turbulence kinetic energy, convection heat transfer coefficient along the fuel sub-channels so that there is an increase in heat transfer coefficient about 40%. The local fuel pin temperature reduction in the place and downstream the space grids due to heat transfer coefficient enhancement is depicted via a graph through six iterations of neutronic and thermal hydraulic coupling calculations. Working in a low fuel temperature and keeping a significant gap below the melting point of fuel, make the IPWR as a safe type of generation -III + nuclear reactor.

• Cross-Cultural Studies
• /
• v.27
• /
• pp.167-195
• /
• 2012

A Chinese female writer Linhaiyin(林海音) and Chengnanjiushi(城南舊事), her representative work, have never been studied in Korea before although she and her literary works stand high and are well known in the history of the modern Chinese literature. Thus, in this paper, I analyze her and her novels included in Chengnanjiushi and study their literary value and meaning. To analyze and study them, I mainly consider novels Anhuiguan, Womenkanhaiqu, Lanyiniang, $L{\acute{\ddot{u}}}dagunr$, and Babadehuarluole included in Chengnanjiushi. Firstly, I look into her attitude and mode to observe children and women's life as a writer. Such attitude and mode succeeded to the spirit of the '5.4 literature'. Secondly, I evaluate Linhaiyin's 'Both sides complex' and its value in the history of literature. From this evaluation, the meaning of Linhaiyin's literature is highlighted. She was free from 'Both sides complex' occurred due to the circumstance of the times and played a role of a bridge so as not to break off literature of China and Taiwan. When her and her works are evaluated, this is one of the most important values. The characteristic of her writing mode is that she did not seek a compelling climax, a surprising reversal, or an exclusive plot or character in her works. In her works, plain description or unwitting conversation and story often imply deep meanings. Thus, at unexpected moment after reading her novels, readers truly listen to deep resonance for her attitude and mode to observe people's life. This is exactly her potential energy that makes readers sink into her literary world regardless of time and space.

• Wind and Structures
• /
• v.27 no.6
• /
• pp.381-397
• /
• 2018

Nonlinear behavior in fluid-structure interaction (FSI) of bridge decks becomes increasingly significant for modern bridges with increasing spans, larger flexibility and new aerodynamic deck configurations. Better understanding of the nonlinear aeroelasticity of bridge decks and further development of reduced-order nonlinear models for the aeroelastic forces become necessary. In this paper, the amplitude-dependent and neutral angle dependent nonlinearities of the motion-induced loads are further highlighted by series of computational fluid dynamics (CFD) simulations. An effort has been made to investigate a semi-analytical time-domain model of the nonlinear motion induced loads on the deck, which enables nonlinear time domain simulations of the aeroelastic responses of the bridge deck. First, the computational schemes used here are validated through theoretically well-known cases. Then, static aerodynamic coefficients of the Great Belt East Bridge (GBEB) cross section are evaluated at various angles of attack, leading to the so-called nonlinear backbone curves. Flutter derivatives of the bridge are identified by CFD simulations using forced harmonic motion of the cross-section with various frequencies. By varying the amplitude of the forced motion, it is observed that the identified flutter derivatives are amplitude-dependent, especially for $A^*_2$ and $H^*_2$ parameters. Another nonlinear feature is observed from the change of hysteresis loop (between angle of attack and lift/moment) when the neutral angles of the cross-section are changed. Based on the CFD results, a semi-analytical time-domain model for describing the nonlinear motion-induced loads is proposed and calibrated. This model is based on accounting for the delay effect with respect to the nonlinear backbone curve and is established in the state-space form. Reasonable agreement between the results from the semi-analytical model and CFD demonstrates the potential application of the proposed model for nonlinear aeroelastic analysis of bridge decks.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
• /
• v.12 no.2
• /
• pp.142-149
• /
• 2019

The coils to transmit the electric energy are necessary to charge an electric vehicle wirelessly. There are several types of coils, from basic circular coils to DD-type coils for enhancing the coupling effect between two coils. However, DD-type coils with a good coupling effect between coils have a disadvantage in use because of the structure complexity of the power conversion device of transmitting and receiving side. In this paper, we propose a method to calculate the inductance value and to design the size of the spiral inductor which is convenient to fabricate when the power is transmitted wirelessly by using two coils in free space. Since the bifurcation phenomenon occurs when the XLm value is similar to the load resistance value in the resonator the XLm value was selected to be equal to the minimum load resistance value to minimize this phenomenon, and the inductance value required for the resonator was calculated. In order to realize the calculated inductance value by the spiral inductor, the relationship between the inductance value and the size, the number of turns, the total coil length of a spiral inductor was investigated. In addition, the change of coupling coefficient k according to the horizontal separation of two coils was examined and an appropriate inductor was selected.

• Tunnel and Underground Space
• /
• v.30 no.6
• /
• pp.591-602
• /
• 2020

Several alternative rock-cutting concepts, which are modified from the conventional ones, have been developed lately. Of the concepts, undercutting is one of the latest technologies. In this study, as a fundamental study on the undercutting technique, the rock-cutting mechanism and important parameters of the undercutting were introduced. This study built up cutting test system for evaluating the cutting performance of an actuated undercutting disc cutter (ADC), and carried out a series of cutting tests under different cutting parameters of ADC. The characteristics of cutter forces obtained from ADC rock-cutting tests were analyzed. The both average and peak values of the three directional cutter forces were linearly increased with the increases of linear velocity, penetration depth in vertical direction and eccentricity of ADC.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.24 no.1
• /
• pp.50-60
• /
• 2021

For conventional AESA radars, DC-DC power modules using 300 Vdc have low efficiency, high volume, heavy weight, and high price, which have problems in modularity with T/R module groups. In this paper, to improve these problems, we propose a distributed DC-DC power module with high-voltage 800 Vdc and high-efficiency Step-down Converter. In particular, power requirements for modern and future marine weapons systems and sensors are rapidly evolving into high-energy and high-voltage power systems. The power distribution of the next generation Navy AESA radar antenna is under development with 1000 Vdc. In this paper, the proposed highvoltage, high-efficiency DC-DC power modules increase space(size), weight, power and cooling(SWaP-C) margins, reduce integration costs/risk, and reduce maintenance costs. Reduced system weight and higher reliability are achieved in navy and ground AESA systems. In addition, the proposed architecture will be easier to scale with larger shipboard radars and applicable to other platforms.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.22 no.2
• /
• pp.644-650
• /
• 2021

This study characterized the reforming of methane with carbon dioxide, which is a major cause of global warming. The methane decomposition reaction with carbon dioxide was carried out using transition metal catalysts. The reactivity of tin was lower than that of a transition metal, such as nickel and iron. Most of the decomposition reaction occurred in the solid state. The melting point of tin is 505.03 K. Tin reacts in a liquid phase at the reaction temperature and has the advantage of separating carbon produced by the decomposition of methane from the liquid tin catalyst. Therefore, deactivation due to the deposition of carbon in the liquid tin can be prevented. Methane decomposition with carbon dioxide produced carbon monoxide and hydrogen. Ni was used to promote the catalyst performance and enhance the activity of the catalyst and lifetime. In this study, catalysts were synthesized using the excess wet impregnation method. The effect of the reaction temperature, space velocity was measured to calculate the activity of catalysts, such as the activation energy and regeneration of catalysts. The carbon-deposited tin catalyst regeneration temperature was 1023 K. The reactivity was improved using a nickel co-catalyst and a water supply.