• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.18 no.1
• /
• pp.90-97
• /
• 2004

In this paper, the optimal position selection of error microphones and control speakers to attenuate interior noise from outside noise sources using active noise control techniques is presented. To get an optimal control characteristics of adaptive noise control systems, it is necessary to optimize the positions of microphones and speakers. New type of simulated annealing method has been proposed as searching techniques to find optimal speakers and microphones positions in which the sum of the squared pressures at microphone positions in an enclosure can be best minimized. Computer simulations and experiments have been performed to show the effectiveness of the proposed method.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.27 no.10
• /
• pp.1-8
• /
• 2013

Wireless Visible Light Communication is the technology that enables communication using LED illumination Infrastructure instead of existing illumination such as incandescent lamp or fluorescent light. Because VLC uses light for communication, it has no problem of frequency permission and is harmless to human body. It is also possible to check the communication through eye. So VLC can be used as a supplement to the Radio Frequency communication, Infrared in indoor environment. So far, researchers on the LED Visible light communication have focused on the increasing transmission speed, transmission distance, modulation method. However, there is few research of main factors that influence on system performance. System performance has been mainly predicted through simulation. In this paper, I recognized that these factors such as outside light noise, obstacle, LED panel position or emitted angle have a great impact on wireless communication system. So I experimented VLC system by changing distance and position to discover location suitable for BER regulation.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.18 no.3
• /
• pp.7-14
• /
• 2004

The metal halide lamps are now widely used in the application and commercial lighting due to their attracting properties such as good color rendering and high efficiency. But, they have a serious problem of acoustic resonance using high frequency operation and they need a high voltage to ignite. So, they have not been applied to indoors. Over the past few years, a considerable number of studies have been conducted on the electronic ballast with hot restarting and resonance phenomenon. But, Very few attempts have been made at adaptive ignition method according to lamp state. In this paper is proposed electronicballast for metal halide lamps with an igniter for adaptive ignition. The proposed electronic bllast can generate a different ignition voltage according to the arc tube state.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.17 no.5
• /
• pp.8-14
• /
• 2003

The daylight responsive dimming system, which uses daylight and automatically controls the light output of electric lighting according to the amount of 3.vailable daylight, is an energy saving system Successful performance relies on how photosensor signal can precisely represent workplace illuminance. However, it is not accurately identified due to the dynamic nature of the sun and the sky changed with respect to different seasons or time. The purpose of this research is to identify the correlation between workplace illuminance and photosensor signals, and propose an optimal location and spatial characteristics of the photosensor through experiments, which minimizes the above impacts and improve system performance.

• Archives of design research
• /
• v.14 no.1
• /
• pp.135-144
• /
• 2001

The purpose of this study is to investigate the relationships between apartment residents'satisfaction and preferences and their environments on purpose to provide useful data for developing new apartment environment based on resident's needs and wants. this research was executed through a questionnaire survey method. The major findings are as follows : (1) Preference of large space of apartment dwelling is still prevailing. The older people have the tendency to prefer orientation to vista. (2) Among environmental factors of livingroom, size is mostly ranked higher than vista and orientation. Result of higher ranking of vista than orientation can be explained with the change of life cycle and patterns based on social environmental change and development of environmental control systems. (3) The highest concern about interior design is targeted to livingroom, and quality of finish materials is preferred at the highest.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.20 no.10
• /
• pp.10-18
• /
• 2006

In this thesis paper the effect that the change in the brightness of headlights has on a driver's perception had been researched. For this research, an indoor laboratory was constructed and designed. Then, a system to measure the reaction braking time of finding obstacle and the subject's brain waves after a moment of change in the headlamp's brightness was constructed. And before the real experiment was began, the trial experiment to decide test time, subject's rest time, detailed experimental steps, the headlamp's patterns of voltage change and an obstacle course was executed.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.24 no.6
• /
• pp.497-508
• /
• 2012

Occupants' visual perception, psychological responses and spatial satisfaction under various indoor lighting environments were analyzed in this study. Field measurements and surveys were conducted in four coffeeshop space where different lighting conditions were used. Results imply that worse visual comfort was reported under direct lighting conditions that exposed light sources to occupants. To improve spatial satisfaction in space, lighting environments should lessen visual thresholds and distraction. Also, necessary illuminance levels should be kept with appropriate color of light that occupants prefer. Worse spatial satisfaction was reported under direct lighting environments, and spatial satisfaction was strongly relevant to visual comfort. Psychological comfort for space was positive in space where visual thresholds were minimized and visual comfort was positively evaluated. Psychological and spatial satisfaction was relevant each other. Occupants preferred to stay longer in space where psychological and spatial satisfaction was positively achieved due to less visual thresholds and improved visual comfort. Better psychological and spatial satisfaction was achieved in space where temporary mood and visual perception were favorably evaluated under indirect lighting environments.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.40 no.2
• /
• pp.385-389
• /
• 2015

If visible light communication is to be used against large background noise in indoor environment, low frequency noise should be avoided. To maintain the advantages of LED lighting while transmitting signals, LEDs should be dimmable and free from flickering effect. In this paper, the spectrum of transmission signal is shifted toward high frequency for this purpose. Specifically, we propose a subpulse-VPPM scheme, which can be designed using only digital components, and we implement a test-bed for performance measurement.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
• /
• 2006.05a
• /
• pp.114-119
• /
• 2006

운전자의 시인성, 뇌파, 심리평가를 위한 실내 실험실 및 측정 시스템을 구축하고 예비실험 결과를 분석한 후 운전자의 시인성을 측정하였다. 본 실험을 위하여 남, 녀 각각 20명의 피험자를 선발하였으며 이들의 연령은 피험자의 연령에 의한 측정오차를 최소화하기 위하여 모두 20대로 제한하였다. 그리고 본 실험 측정결과를 전압패턴에 따라 피험자의 장애물 인식 반응속도를 분석하였고, 남-녀 성별 간의 장애물 인식 반응속도 차이를 분석하였다. 또한 전조등의 전압변동에 의한 밝기 비율에 따라서 피험자의 장애물 인식 반응속도를 분석하였고, 전압변동이 없을 때의 장애물 인식 반응속도를 기준으로 상대적인 장애물 인식 지연시간을 분석하였다.

• Journal of the Korea Furniture Society
• /
• v.24 no.1
• /
• pp.33-41
• /
• 2013

As professional postnatal care systems have been rapidly supplied, there is sharp increase of postnatal care centers without legal regulations for a mother and a infant. For the quick recovery of mothers, newborn infants that have weaker immune systems are being managed in group in the postnatal care centers. Recently, the attention of the postnatal care centers has been growing because the problem of pneumonia which led to result in a casuality in a infant unit was happen. So, this research analyzed the indoor environment of infant unit through measuring formaldehyde, carbon dioxide, intensity of illumination. As a result of the data, infant units showed higher concentration of formaldehyde and carbon dioxide than Indoor Air Quality Control Law. Moreover, infant units was measured higher intensity of illumination than the range of optimum illumination for infants.