• KSII Transactions on Internet and Information Systems (TIIS)
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• 제6권12호
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• pp.3182-3196
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• 2012

In this paper, we present a new LED (Light Emitting Diode) mood lighting system interacting with smartphones based on the generation of different light sequences. In the proposed system, one light sequence is considered to be one unit of the service contents, which is then transmitted through a network and played in an LED lighting system. To this end, we propose a novel generation scheme using a smartphone, and a decoding/playing mechanism in an LED lighting system. The lighting sequences have a fixed period divided into predefined time units. Two modes - basic and interpolation - are supported in each time unit when playing a color sequence. In the basic mode, the color is maintained for the entire time unit, whereas in the interpolation mode the color is interpolated. The sequence is decoded and played in the lighting circuit by changing the duty cycle of a PWM (Pulse Width Modulation) signal. A demonstration system of the overall proposed method was using smartphones, a server and an LED lighting system. The results from this experiment show the validity and applicability of the proposed scheme.

• 교육녹색환경연구
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• 제12권2호
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• pp.61-70
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• 2013

As the existing school building power consumption is expressed by total power consumption, in the view of energy saving is disadvantage. The the power consumption of school building is divided as cooling, heating, lighting and others. The cooling power consumption, heating power consumption, lighting power consumption can be calculated using real total power consumption that gained from Korea Electric Power Corporation(KEPCO). The power consumption for cooling and heating can be calculated using heat transmittance, wall area and floor area, and for lighting is calculated by artificial lighting calculation. but this calculation methods is difficult for laymen. This study was carried out in order to establish the regression equation for cooling power consumption, heating power consumption, lighting power consumption and other power consumption in school building. In order to verify the validity of the regression equation, it is compared regression equation results and calculation results based on real power consumption. As the results, difference between regression result and calculation results for cooling and heating power consumption showed 0.6% and 3.6%.

• 설비공학논문집
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• 제23권4호
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• pp.287-296
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• 2011

This study examines the influences of correlated color temperature and illuminance on visual perception and temporary mood sensation in a small office. Field measurements and surveys were conducted in a full-scale mock-up model. Twenty subjects participated in the survey under six lighting conditions formed by three color temperature and two illuminance levels. Results indicate that 4000 K color temperature was effective to mitigate glare sensation from light source. Lamps with low color temperature such as 2700 K was not recommended for office lighting since they are likely to caused glare and visual discomfort. Preferred color temperature was 4000 K and 6500 K for 750 lx and 500 lx target illuminance respectively. The increase of illuminance was not an effective contributor to improve mood perception. The illuminance should be lower than 500 lx to achieve good mood, but the illuminance level in office space should be considered with visual performance simultaneously. This study suggests that fluorescent lighting fixtures with 4000 K lamps would be usefully used for office lighting since they formed friendly conditions for better visual performance.

• 조명전기설비학회논문지
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• 제26권4호
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• pp.6-13
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• 2012

In this paper, we took an indirect reflectance type that irradiates light from an LED module, which reflects light from a reflector onto the road. This LED pedestrian lighting design produces minimal glare from a relatively simple structure. Using LightTools 7.2, we conducted a study on the varying shape and curvature of the reflector. In order to further investigate this data, we researched the ratio of the DLOR and ULOR, the average illuminance, and the uniformity of the illumination. Based on this research, we selected optimum conditions to realize the actual LED pedestrian lighting using RELUX software. We found the average illuminance value to be 22[1x] and the illuminance uniformity ratio to be 0.23, which met the criteria of the proposed standards set in KS C 7658. In addition, it also satisfied the criteria of the standards set in KS A 3701 by having TI (Threshold Increment) at 7[%].

• Journal of Electrical Engineering and Technology
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• 제9권5호
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• pp.1643-1653
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• 2014

This paper presents the design and implementation of a wind-solar hybrid power system for LED street lighting and an isolated power system. The proposed system consists of photovoltaic modules, a wind generator, a storage system (battery), LED lighting, and the controller, which can manage the power and system operation. This controller has the functions of maximum power point tracking (MPPT) for the wind and solar power, effective charging/discharging for the storage system, LED dimming control for saving energy, and remote data logging for monitoring the performance and maintenance. The proposed system was analyzed in regard to the operation status of the hybrid input power and the battery voltage using a PSIM simulation. In addition, the characteristics of the proposed system's output were analyzed through experimental verification. A prototype was also developed which uses 300[W] of wind power, 200[W] of solar power, 60[W] LED lighting, and a 24[V]/80[Ah] battery. The control system principles and design scheme of the hardware and software are presented.

• Current Optics and Photonics
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• 제7권6호
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• pp.755-760
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• 2023

In this paper, an illumination optical system that can mitigate the saturation phenomenon in the center of an image (caused by the typical flexible-endoscope illumination system using LEDs with Lambertian light distribution) is designed. When an LED with Lambertian light distribution is used as a light source, the amount of light in the center of the endoscopic illumination system is relatively high, compared to the periphery, causing saturation in the image. Since this phenomenon causes difficulty in detecting the patient's lesion, it is necessary to find a lighting-system design that can alleviate the saturation phenomenon. Therefore, in this paper a lighting system with bat-wing light distribution, which can lower the intensity at the center and secure the maximum amount of light at the maximum light distribution angle, is designed. In addition, to check the performance of the designed lighting system, a simulation of illumination and luminance is conducted for a system using a common aspherical lens with otherwise the same components. As a result, it is confirmed that the lighting system designed in this paper effectively reduces the luminance value at the center and secures more luminance values at the periphery than the familiar lighting system.

• 한국조경학회지
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• 제46권2호
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• pp.14-26
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• 2018

빛은 인간 생활을 결정하는 중요한 요소이다. 인류가 인공적으로 빛을 다룰 수 있게 된 이래 조명은 도시의 야간문화와 경관을 획기적으로 바꾸어 놓았다. 야간 경관은 도시의 정체성에 지대한 영향을 미친다. 시민들의 야간 활동이 늘어나면서 조명에 대한 다양한 요구가 늘어나는 추세이지만, 정작 경관을 다루는 조경 분야의 계획 설계과정에서 조명계획은 비중 있게 다루어지지 않았다. 본 연구는 우리나라 도시공원의 야간경관의 실태를 분석하기 위해 공원의 계획 및 조성 과정과 제도적 측면의 문제점을 파악하고, 여의도공원을 대상으로 도면 분석과 현장 조사를 통해 문제점을 도출하였다. 현재 도시공원의 야간경관과 관련한 실태 분석의 결과는 다음과 같다. 첫째, 공원의 계획 설계 과정에서 조명계획은 설비 분야에 포함되어 개략적인 수준으로만 다루어져왔고, 이는 실제 공원의 단조로운 야간경관을 초래했다고 볼 수 있다. 따라서 공원의 분석-계획-설계-시공-관리 과정에서 야간경관의 연출을 적극적으로 수용할 수 있는 방법론이 개발되어야할 것이다. 둘째, 현재 도시공원에 적용 가능한 기준은 한국산업규격(KS A 3011)의 수평조도 규정에 그치고 있어 야간경관 평가와 계획의 세부 기준 항목을 다양하게 개발할 필요가 있다. 셋째, 성장하는 수목과 복합적인 자연생태계의 특성을 고려할 수 있는 야간경관 설계 및 관리 방안이 필요하다. 넷째, 공원의 공간별 특성에 맞는 세부 디자인 가이드라인과 관련 기준이 필요하다.

• KIEAE Journal
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• 제17권3호
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• pp.91-97
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• 2017

Purpose: Various studies on a light shelf are in progress, but it has the problem of glare occurrence. The present study suggested a diffusion film as the method for resolving the glare problem, and aimed to establish light shelf-related basic data by conducting the performance evaluation of a light shelf depending on the installation position of the diffusion film. Method: To carry out the light shelf performance evaluation depending on the diffusion film installation position, three cases were established: no diffusion film installation (Case 1), diffusion film installation on the reflector (Case 2), and diffusion film installation on the upper glass surface of the window for light shelf installation (Case 3); and the energy reduction performance, luminance, and luminance contrast were analyzed based on a testbed. Result: The conclusions of this study are as follows. 1) When the diffusion film was applied, the amount of light introduced through the light shelf decreased, and the average indoor illumination decreased accordingly. 2) For Case 3, the lighting energy reduction performance was identical to the lighting energy reduction efficiency of the existing light shelf; and for Case 2, it was found to be inappropriate as the lighting energy consumption increased compared to that of the existing light shelf. 3) The analysis of the glare for the cases established in this study showed that the luminance contrast was low for Case 3, and thus the glare problem could be minimized. 4) The specific angle of the light shelf could induce the glare problem by increasing the luminance depending on the external condition. 5) Based on the aforementioned contents, the installation position of the diffusion film for improving the lighting performance and glare problem of the light shelf was found to be the upper glass surface of the window for light shelf installation.

• 스마트미디어저널
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• 제5권4호
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• pp.103-110
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• 2016

본 연구는 유사 목적을 가진 제품들을 형태적 특성에 따라 분류하고, 기능적 유사성을 기반으로 범주화하여 전형성 추출함으로써 기구디자인 개발 시, 개발방향의 기준 마련에 목적을 둔다. 전형성 추출을 위한 본 연구의 표본영역은 선험 사례연구와 전문가자문을 통해 팬던트형과 천정부착형으로 제한을 두고, 한국과 일본에 출시된 2015년 12월 이전 출시 제품을 표본으로 국내 주요 6개 도시 관련업무 종사자 및 전공자를 대상으로 조사를 실시하였다. 조사는 형태적 분류를 위한 1차 조사와 전형성 추출에 관한 2차 조사, 형태적 디자인속성 분류에 관한 3차 조사로 이루어졌으며, 기능 및 형태적 분류와 조형원리를 기준으로 디자인 속성을 도출하고 개별 요소를 추출함으로써 디자인 가중치 측정에 대한 향후 연구의 기반을 마련하고자 하였다. 연구결과의 산업적 적용으로 광원 대체로 인한 조명기구 시장변화에 디자인기술의 효율적 역할 정립과 기업의 연구개발 및 조명기구관련 제품디자인 타입 변화 가속화에 신속한 대응방향 제시 효과를 기대할 수 있다.

• International Journal of Advanced Culture Technology
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• 제8권1호
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• pp.207-212
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• 2020

The human centric lighting (HCL) control is a major focus point of the smart lighting system design to provide energy efficient and people mood rhythmic motivation lighting in smart buildings. This paper proposes the HCL control using indoor surveillance camera to improve the human motivation and well-beings in the indoor environments like residential and industrial buildings. In this proposed approach, the indoor surveillance camera video streams are used to predict the day lights and occupancy, occupancy specific emotional features predictions using the advanced computer vision techniques, and this human centric features are transmitted to the smart building light management system. The smart building light management system connected with internet of things (IoT) featured lighting devices and controls the light illumination of the objective human specific lighting devices. The proposed concept experimental model implemented using RGB LED lighting devices connected with IoT features open-source controller in the network along with networked video surveillance solution. The experiment results are verified with custom made automatic lighting control demon application integrated with OpenCV framework based computer vision methods to predict the human centric features and based on the estimated features the lighting illumination level and colors are controlled automatically. The experiment results received from the demon system are analyzed and used for the real-time development of a lighting system control strategy.