• Title/Summary/Keyword: Low intensity of illumination

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Improved Heat Lamp for Preventing Arterial Spasm after Microvascular Surgery (미세혈관 수술 후 혈관 연축의 예방을 위한 개선된 온열전등)

  • Ahn, Sung-Min;Hwang, So-Min;Hu, Eun-Suk;Park, Jung-Mi;Park, Kyung-A;Oh, Jin-A
    • Archives of Reconstructive Microsurgery
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    • v.17 no.2
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    • pp.120-125
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    • 2008
  • Purpose: Heat therapy by heat lamp after microvascular surgery is being used for preventing blood vessels's contraction and blood-flow's disturbance. As usually, incandescent lamp has been used. But there have been several problems and need for improvement in the existing heat lamp treatment. So we would like to introduce improved heat lamp to keep an appropriate temperature and intensity of illumination. Methods: The existing heat lamps are the ones of general light stands covered with newspaper, having 60 watt light bulb of incandescence and lampshade made of aluminum. We have tried to improve shortcomings of the existing heat lamps by enlarging the size of aluminum lampshade and attaching a curtain that can block heat and light. We conducted a comparative study between the existing and improved heat lamps. Under the assumption that there are several affected parts, we have also measured the distance from heat lamp to patients' eye region and then intensity of illumination. Result: The target temperature of surface was realized in 11 minutes with the maximum temperature reaching at 36.6 degrees C in 28 minutes at the existing heat lamp while the target temperature reached in 7 minutes with the maximum temperature reaching at 39.0 degrees C in 17 minutes at the improved heat lamp. The existing and improved heat lamp showed 38 lx and 0.1 lx of intensity of lumination, respectively. Conclusion: Using improved heat lamps, we can keep an appropriate temperature and we think we can make contribution to patients' treatment by making them and their neighbors able to sleep with minimized disturbance thanks to low intensity of illumination secured by blocking light.

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A Study on Light Guide Luminaire Design using Prismatic Film (프리즘 필름을 이용한 조명기구 설계 연구)

  • Jeong, Hak-Geun;Han, Su-Bin;Jung, Bong-Man;Lee, Euy-Jun
    • KIEAE Journal
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    • v.2 no.2
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    • pp.33-38
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    • 2002
  • There are a number of practical uses for devices which are capable of piping large amounts of light: illumination of areas where there would be maintenance, safety, or security problems with electronic light sources; piping sunlight into indoor areas for illumination; and the conversion of high luminous efficacy, good color quality, high intensity discharge lamps into more acceptable linear of area sources of light. Prism light guides are hollow structures which pipe light by means of total internal reflectin(TIR). These devices are unique in their ability to combine the efficiency of TIR with the relatively low cost of hollow structure. An important application stems from their ability to transform a point source of light such as an incandescent or discharge lamp into a linear or area source of light or illumination. We report the development of an economical, flexible prismatic film for fabricating the light guide wall. This guide geometries and films are currently under development.

Effect of Light on the Sclerotial Formation of Sclerotinia sclerotiorum(Lib.) de Bary (균핵병균(Sclerotinia sclerotiorum(Lib.) de Bary)의 균핵형성에 미치는 광선의 영향)

  • Kim Ki Chung
    • Korean journal of applied entomology
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    • v.15 no.3 s.28
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    • pp.153-159
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    • 1976
  • Present paper was attempted to investigate the effects of the light on the sclerotium formation of some isolates of Sclerotinia sclerotiorum(Lib.) do Bary from lettuce, cucumber and rape. The investigations were performed in the both aspects inducing sclerotial primordia from the mycelial colony and developing such primordia. The cultures were grown on potato-dextrose agar and were treated with day-light fluorescent lamps. In the continuous light illumination for 21 days, numbers of sclerotial primordia and matured sclerotia were increased with increasing the light intensity up to about 500 Lux, but on the contrary the dry-weight of matured sclerotia was decreased. In the 800 Lux illumination, induction of the primordia was extremely depressed, and then matured sclerotia were almost not produced. Short-time illumination for 48 hours, although the light intensity was as high as 5000 Lux, increased the numbers of sclerotial primordia and matured sclerotia. Dry-weight of matured sclerotia, however, was slightly increased only at low intensity of 160 Lux. On the other hand, the light shock which u·as alternatively on-of light every one minute for 48 hours increased the number and dry-weight of sclerotia produced, but the former was more effective at 500 Lux shock and the later more effective at 160 Lux shock.

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Heat Sink of LED Lights Using Engineering Plastics (엔지니어링 플라스틱의 LED조명 방열판 적용)

  • Cho, Young-Tae
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.12 no.4
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    • pp.61-68
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    • 2013
  • As an advance study for the development of a heat sink for special purpose high power illumination, an investigation was made to find feasibility for the application of copper plated EP to a heat sink of small LED light of less than 10W installed in commercial product. In this study, the plated heat sink with EP copper was fabricated for the conventional LED light. It was used actually for finding heat radiation property and effectiveness of the heat sink accompanied with measurement of luminous intensity. The heat is radiated by transfer and dissipation only through the copper plated surface due to extremely low heat conductivity of EP in case of EP heat sink; however the total area of the plate plays the function of heat transfer as well as heat radiation in case of the aluminum heat sink. It seems that the volume difference of heat radiating material is so big that the temperature $P_1$ is 9.0~12.3% higher in 3W and 42.7~54.0% higher in case of 6W volume difference of heat radiating material is so big that the temperature $P_1$ is 9.0~12.3% higher in 3W and 42.7~54.0% higher in case of 6W even though heat transfer rate of copper is approximately 1.9 times higher than that of aluminum. It was thought that this is useful to utilize for heat sink for low power LED light with the low heating rate. Also, the illumination could be greatly influenced by the surrounding temperature of the place where it is installed. Therefore, it seems that the illumination installation environment must be taken into consideration when selecting illumination. Further study was expected on order to aims at development of an exterior surface itself made into heat radiation plate by application of this technology in future.

Face Representation Based on Non-Alpha Weberface and Histogram Equalization for Face Recognition Under Varying Illumination Conditions (조명 변화 환경에서 얼굴 인식을 위한 Non-Alpha Weberface 및 히스토그램 평활화 기반 얼굴 표현)

  • Kim, Ha-Young;Lee, Hee-Jae;Lee, Sang-Goog
    • Journal of KIISE
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    • v.44 no.3
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    • pp.295-305
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    • 2017
  • Facial appearance is greatly influenced by illumination conditions, and therefore illumination variation is one of the factors that degrades performance of face recognition systems. In this paper, we propose a robust method for face representation under varying illumination conditions, combining non-alpha Weberface (non-alpha WF) and histogram equalization. We propose a two-step method: (1) for a given face image, non-alpha WF, which is not applied a parameter for adjusting the intensity difference between neighboring pixels in WF, is computed; (2) histogram equalization is performed to non-alpha WF, to make a uniform histogram distribution globally and to enhance the contrast. $(2D)^2PCA$ is applied to extract low-dimensional discriminating features from the preprocessed face image. Experimental results on the extended Yale B face database and the CMU PIE face database show that the proposed method yielded better recognition rates than several illumination processing methods as well as the conventional WF, achieving average recognition rates of 93.31% and 97.25%, respectively.

Development of Remote Control and Monitoring System for HID Street-lamp Based on Low Cost Zigbee Communication Network (저 가격형 Zigbee 통신 네트워크 기반 HID 가로등의 원격 제어 및 감시 시스템 개발)

  • Chung, Wan-Sup;Kim, Yang-Bae;Shon, Jin-Geun
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.63 no.2
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    • pp.69-73
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    • 2014
  • In this paper, remote control and surveillance monitoring system of HID street-lamp using low-cost type of Zigbee communication module was developed. A plurality of capacitors with different capacity are attached to magnetic ballast for HID lamps. Changes in the amount of illumination can be adjusted by the changes in capacity so that the electric energy can be reduced. In Zigbee communication module, a ATmega128L microprocessor is used and in main CPU, ARM9 Core is used to construct a low-cost smart system. In surveillance monitoring systems, the system was configured to remote monitoring of presence of error in the lamp abnormalities, the status of leakage current and abnormalities of ballasts and capacitors and the validity of the proposed empirical experiment was confirmed.

A Study on Depth Information Acquisition Improved by Gradual Pixel Bundling Method at TOF Image Sensor

  • Kwon, Soon Chul;Chae, Ho Byung;Lee, Sung Jin;Son, Kwang Chul;Lee, Seung Hyun
    • International Journal of Internet, Broadcasting and Communication
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    • v.7 no.1
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    • pp.15-19
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    • 2015
  • The depth information of an image is used in a variety of applications including 2D/3D conversion, multi-view extraction, modeling, depth keying, etc. There are various methods to acquire depth information, such as the method to use a stereo camera, the method to use the depth camera of flight time (TOF) method, the method to use 3D modeling software, the method to use 3D scanner and the method to use a structured light just like Microsoft's Kinect. In particular, the depth camera of TOF method measures the distance using infrared light, whereas TOF sensor depends on the sensitivity of optical light of an image sensor (CCD/CMOS). Thus, it is mandatory for the existing image sensors to get an infrared light image by bundling several pixels; these requirements generate a phenomenon to reduce the resolution of an image. This thesis proposed a measure to acquire a high-resolution image through gradual area movement while acquiring a low-resolution image through pixel bundling method. From this measure, one can obtain an effect of acquiring image information in which illumination intensity (lux) and resolution were improved without increasing the performance of an image sensor since the image resolution is not improved as resolving a low-illumination intensity (lux) in accordance with the gradual pixel bundling algorithm.

Estimation of Disparity Map having Reliability to Changes of Radiometric (Radiometric 특성 변화에 신뢰성을 가지는 Disparity Map 예측)

  • Shin, Kwang-mu;Kim, Sung-min;Cho, Mi-sook;Chung, Ki-dong
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2015.10a
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    • pp.93-96
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    • 2015
  • The aim of the estimation of disparity map is to find the corresponding pixels from similar two or more images. However, it is a difficult problem to get precise and consistent disparity under a variety of real world situations. In other words, the color values of stereo images are easily influenced by radiometric properties such as illumination direction, illumination color, and camera exposure. Therefore, conventional stereo matching methods can have low performances under radiometric conditions. In this paper, we propose an approaching of disparity map estimation that is reliable in controlling various radiometric variations close to the real environment. This method is motivated by following constancy. Even though each other has different radiometric property in stereo images, intensity of pixels of object have general constancy in specific block. Experimental results show that the proposed method has better performances compared to the comparison group under different radiometric conditions between stereo images. Consequentially, the proposed method is able to estimate the disparity map in stable under various radiometric variations.

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Detection of a Light Region Based on Intensity and Saturation and Traffic Light Discrimination by Model Verification (명도와 채도 기반의 점등영역 검출 및 모델 검증에 의한 교통신호등 판별)

  • Kim, Min-Ki
    • Journal of Korea Multimedia Society
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    • v.20 no.11
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    • pp.1729-1740
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    • 2017
  • This paper describes a vision-based method that effectively recognize a traffic light. The method consists of two steps of traffic light detection and discrimination. Many related studies have used color information to detect traffic light, but color information is not robust to the varying illumination environment. This paper proposes a new method of traffic light detection based on intensity and saturation. When a traffic light is turned on, the light region usually shows values with high saturation and high intensity. However, when the light region is oversaturated, the region shows values of low saturation and high intensity. So this study proposes a method to be able to detect a traffic light under these conditions. After detecting a traffic light, it estimates the size of the body region including the traffic light and extracts the body region. The body region is compared with five models which represent specific traffic signals, then the region is discriminated as one of the five models or rejected as none of them. Experimental results show the performance of traffic light detection reporting the precision of 97.2%, the recall of 95.8%, and correct recognition rate of 94.3%. These results shows that the proposed method is effective.

Comparative Performance Evaluation of Binarization Methods for Vehicle License Plate (자동차 번호판 이진화 방법에 대한 성능 비교)

  • Kim, Min-Ki
    • The Journal of the Korea Contents Association
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    • v.9 no.8
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    • pp.9-17
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    • 2009
  • License plate recognition is an active research area. but few comparative studies on license plate binarization have been conducted. Many related researchers have experienced similar trial and error for finding an effective binarization method. To reduce this trial and error, this study implemented some binarization methods and quantitatively compared the performance of the methods. The performance evaluation consists of a low level measure and a high level measure, so it can evaluate not only the quality of binarized image itself but also the usefulness of the result. The performance evaluation was separately performed with three groups of images so as to understand the properties of the binarization methods. Experimental results show that the quality of binarization is more dependent on the evenness of illumination than the intensity of illumination. The Otsu's method has acquired the most effective performance in the group of even illumination images and the Niblack's method with parameter correction has shown the best quality in the group of uneven illumination images.