• Journal of Korean Association for Spatial Structures
• /
• v.10 no.3
• /
• pp.75-80
• /
• 2010

The present study tried to provide useful data for the acoustic design of sound amplification system with measuring and analyzing subjective preference and intelligibility by varying the number of speakers and their directivity. The results suggest that the room absorption plays a key role in subjective responses of listeners and the large sound absorption of ceiling contributes to the increase of intelligibility. Also, larger number of speakers with narrow directivity improves perceived intelligibility when speakers were installed at the lower height. However, the highest degree of intelligibility and preference were obtained when speakers were installed close enough to the sound absorptive ceiling. The highest intelligibility and preference were observed when 8 to 10 speakers with the directivity of 60 degree were used.

• Proceedings of the SAREK Conference
• /
• 2006.06a
• /
• pp.1180-1185
• /
• 2006

Modern people spend most of time at indoor space, such as office or classroom. Especially, occupants are exposed to the airtight indoor air quality (IAQ) for a long time, At present, many studies on the air-conditioning systems are more focused on the individual thermal comfort than the thermal efficiency due to increase of the concern of health. There are several factors which are influenced thermal comfort, such as temperature, humidity, convection and air movement, etc. Also, the individual factor, such as age, gender, Physical constitution and habit, should be considered. The 4-way cassette type air conditioner is known to bring out better performance about thermal comfort than the traditional one. This study is performed on the higher ceiling environment than the common buildings or classrooms. Also, this study analyzed on the Indoor thermal comfort by diffusing direction of 4-way cassette air conditioner with various discharge angles, $45^{\circ},\;50^{\circ},\;55^{\circ}$ and $60^{\circ}$. Using a commercial code, FLUENT, three-dimensional transient air thermal flow fields are calculated with appropriate wall boundary conditions and standard $k-{\epsilon}$ turbulence model. Results of velocity and temperature distributions are graphically depicted with various discharge angles.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.18 no.5
• /
• pp.716-722
• /
• 2017

The present study numerically investigates the effect of obstacles located in the trajectory of fire plume flow on heat flow characteristics by using Fire Dynamics Simulation (FDS) software in an underground combined cycle power plant (CCPP). Fire size is taken as 10 MW and two different locations of fire source are selected depending on the presence of an obstacle. As the results, when the obstacle is in the trajectory of fire plume, hot plume arrives at the ceiling about 5 times slower in the upper of the fire in comparison to the results without obstacle. In addition, the average propagation time of ceiling jet increases by about 70 % with the distance from the ceiling in the upper of the fire, and it increases mainly about 4 times at the distance of 10 m. Consequently, it is noted that the analysis of heat flow characteristics in the underground CCPP considering fire scenarios is essential to develop the fire detection system for initial response on evacuation and disaster management.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.14 no.1
• /
• pp.7-13
• /
• 2000

It is important to decide the best beneficial lighting system in the space when we design the lighting at first stage. A Worksheet to simplify the evaluation of the economics of the lighting system was developed. And it was applied to a general office room for each lamp and ballast combinations, and to a factory room with a high ceiling for each HID lamp systems. When we design the lighting system using the Worksheet, we can easily evaluate the economics through converting the total cost invested on the lighting system to the present value or the annual cost.

• Proceedings of the KIEE Conference
• /
• 2011.07a
• /
• pp.1274-1275
• /
• 2011

This paper study effects that measured hamony occurence and changes of current and voltage according to variation of temperature of Far Infrared Ray Radiant Oven's room affect power quality.

• Proceedings of the Korean Information Science Society Conference
• /
• 2001.04b
• /
• pp.277-279
• /
• 2001

인터넷과 웹의 발전으로 인한 정보량이 급격한 증가로 정보를 수집 하는데 있어 많은 어려움에 부딪치게 되었다. 근래 이런 복잡한 문제를 해결하고자 하는 노력이 에이전트 연구와 접목되어 시도되고 있다. 정보량의 급증으로 인해 로봇을 사용하는 시스템들은 로테이션 타임의 길어지고, 네트웍 망의 과부하를 급증시키고 있다. 이런 문제를 해결하고자 트리거(Trigger) 에이전트를 제안한다. 트리거 에이전트는 웹 서버에 에이전트를 래핑 하여 문서를 모니터링 하게 하고 문서의 갱신이 발생하면 이때 서버에 로봇을 요청하여 문서를 수집하는 아키텍쳐를 가진다.

• Proceedings of the KIEE Conference
• /
• 2008.07a
• /
• pp.960-961
• /
• 2008

본 논문에서는 직선 및 곡선구간에서 구동력을 필요로 하는 LCD 패널 생산라인의 이송장비인 OHS 시스템에 적용이 가능한 횡자속 선형전동기의 제어에 관하여 기술한다. OHS 시스템은 클린룸 내에서 이송대차가 천장에 레일과 함께 설치되어 장거리의 직선 및 곡선 이송경로를 가지는 LCD 패널 물류 이송장치이다. 기존 선형전동기들은 그 구조상 곡선구간 구동원으로 적용하기 어렵고, 장거리 이송용으로 사용하기에 상당한 가격적인 부담이 발생된다. 따라서 본 논문에서는 상대적으로 다른 선형전동기와 비교하여 가격적인 부담이 적고, 곡선구간에서 구동력을 발휘할 수 있는 횡자속 선형전동기를 OHS 시스템에 적용하고, 선형전동기의 곡선구간에서의 출력특성을 분석하며, 이동자의 위치검출 방법 및 제어 알고리즘을 제안한다. 제안한 방법은 실제 제작된 OHS 실험장치를 통하여 제어특성을 검증한다.

• Proceedings of the Korean Society of Computer Information Conference
• /
• 2022.07a
• /
• pp.737-740
• /
• 2022

본 논문에서는 AR Founation을 이용하여 조명기기를 생활공간에 배치시키는 소비자 맞춤형 증강현실 시스템을 제안한다. 시스템은 조명기기를 다양한 고객의 요구에 맞추어 바닥, 벽면, 천장에 맞게 배치 시킬 수 있는 솔루션을 제공한다. 우선 조명기기를 3D 스캐너를 이용하여 3차원 모델링을 한다. 그리고 모델링된 개체에 블렌더를 이용하여 받침대 및 부수적인 요소를 추가하여 3차원 조명기기를 완성한다. 완성된 조명기기는 사용자의 요구에 따라 3차원 공간상에 위치 시킬 수 있는 기능을 제공한다. 이와 같은 시스템은 스마트 기기를 활용하여 간단한 스마트폰 터치를 통해 손쉬운 공간 설계 지원이 가능하다. 구현된 시스템은 모바일 AR 어플리케이션 개발을 통하여 기존의 AR 어플리케이션의 가구 배치 프로그램에 비해 다양한 연출 효과를 줌으로써 사용자에게 생생한 현장감을 주는데 효과적이다.

• Journal of the Computational Structural Engineering Institute of Korea
• /
• v.17 no.3
• /
• pp.241-249
• /
• 2004

There is an over head hoist transporter(OHT) by the system for delivering the wafer in semiconductor processing. The transfer system consist of carrier, vehicle, rail and support. The Tail supporting the wafer and the transfer system should maintain enough strength and stiffness. To achieve lightness and enough strength and stiffness, optimization algorithm should be introduced in design process. In this study, two kinds of section shapes as L-type, C-type is carried out the structure analysis and optimization. Total weight of rail is to be minimized while displacement should not exceed limit. To improve the initial model, topology optimization is done by the plain problem. Size optimization is done with 3D solid element and PLBA algorithm, the RQP algorithm. The weight of optimum model as L-type, C-type is decreased by 2.3%, 10% respectively. It is improved better than the initial model in the strength and stiffness of the structure.

• Fire Science and Engineering
• /
• v.25 no.6
• /
• pp.51-57
• /
• 2011

The domestic wooden cultural properties applied to the sprinkler extinguishing system was confirmed extinguishing performance through fire experiments. Consists of wooden cultural properties of a fire, a flammable material is vulnerable in terms of. The scale of fire will occur to vary appearance of the initial fire in case of arson. Sprinkler nozzles of the characteristics, the discharging pressure is 1 bar and the flow rate is 80 lpm, applied in this experiment. Fire performance experiments were tested in two separated in each of the scale of the fire and cultural properties. Fire extinguishing performance test results was low in high ceilings and two or more units of the fire scale. Fire growth environment of the actual wooden cultural properties to experimental models when you consider that it is more vulnerable, sprinkler extinguishing system is required sufficient verification in order to apply fire protection of the wooden cultural properties.