• Title/Summary/Keyword: Relative illumination

Search Result 77, Processing Time 0.058 seconds

Polarization Spectral Imaging System for Quantitative Evaluation of Port Wine Stain Blanching Following Laser Treatment

  • Jung, Byung-Jo
    • Journal of the Optical Society of Korea
    • /
    • v.7 no.4
    • /
    • pp.234-239
    • /
    • 2003
  • Objective methods to assess quantitatively port wine stain (PWS) blanching in response to laser therapy are needed to improve laser therapeutic outcome. Previous studies have attempted to assess objectively PWS color based on point measurement devices. To date, these approaches have typically been limited by a number of factors such as small test area and need for contact. To address these issues, a polarization spectral imaging system and an image analysis method have been developed to evaluate quantitatively erythema and melanin content distribution in skin. The developed polarization spectral imaging system minimizes artifacts such as glaring, shadowing, and non-uniform illumination that interfere with image fidelity. Furthermore, the image analysis method has been employed to get images of skin melanin and erythema indices from the acquired color images for quantitative analysis. Finally, using PWS patient color image, the effectiveness in laser treatment of PWS was evaluated by calculating relative erythema index image that is the relative erythema index of PWS region to the normal region. The developed device and analysis method appears to be a simple and effective method for quantitative analysis of PWS blanching.

A Study on Air Pollution in Indoor Gymnasiums (실내체육관에서의 공기오염에 관한 연구)

  • 윤승욱;김윤신;이종대;이철민;조용성
    • Journal of Environmental Health Sciences
    • /
    • v.26 no.3
    • /
    • pp.32-37
    • /
    • 2000
  • Nowadays, a new word called SBS(sick building syndrome) has been come into existence. At the point of time when an interest about indoor air pollution and, according to this, countermeasure plan are internationally. Moreover institutional countermeasure should be attended at national level since indoor air quality in public places where many people gather is directly connected with national health. Especially indoor pollution of indoor stadia where all sorts of sports are held can give rise to every kinds of respiratory ailments to players as well as audiences. So it is presented as a main factor that indoor space of stadia is crowded with players and audiences compared with other kinds of indoor space. Therefore, in this research to analyze pollution degree of indoor circumstance for gymnasium and exercising room of folk wrestling. basketball, judo, wrestling, hapkido, swordsmanship and boxing making indoor gymnasium and exercising room an object, when 7 items were measures such as thermocircumstance(temperature, relative humidity, air current, intensity of illumination), dust, carbon monoxide, and carbon dioxide being based on the indoor environmental standard of the first clause of Article 45 of public utilization service which is showed at public hygiene of the Ministry of Health and Social Affairs, it was showed that indoor temperature, relative humidity, air current and intensity of illumination were over standard amount at the most of folk wrestling gymnasium and exercising room. Indoor density of carbon monoxide was preserved to the extent of standard amount (10ppm) at all gymnasiums but carbon dioxide was not in excess of standard amount(1,000 ppm) at most of gymnasiums. Indoor density of dust induced from respiration exceeded the standard amount (150 $\mu\textrm{g}$/㎥) at all gymnasiums of the folk wrestling. Since the folk wrestling players and participants feel physical subjective symptom seriously, in other words the degree of indoor air pollution at gymnasiums and exercising rooms of the folk wrestling is very high, fundamental solution and countermeasure plan should be presented.

  • PDF

Development of Guidelines for Indoor Environment in Apartment Remodeling Projects (아파트 리모델링의 실내환경 계획지침 개발)

  • Choi, Yoon-Jung
    • Journal of the Korean housing association
    • /
    • v.20 no.3
    • /
    • pp.1-10
    • /
    • 2009
  • The final aim of this study was to propose guidelines for the indoor environment of apartment remodeling projects. The first task of this study was to understand the major elements and the actual condition of the remodeling for apartment unit by carrying out in-depth interviews on residents and specialists. The open-access interviews were conducted with interior designers who have a wide experience of apartment remodeling and residents who live in recently remodeled apartment units. The second task was to evaluate the actual condition of the indoor environment and to analyze the main factors that affect the indoor environment in remodeled apartment units. Field measurements were carried out in twenty apartment units occupied after remodeling, recording indoor environment elements (indoor temperature, globe temperature, relative humidity, $CO_2$, CO, PM10, TVOC, HCHO, illumination, and equivalent noise level). Moreover, resident interviews and researcher observations were carried out to determine the contents of the remodeled unit and to investigate the architectural and living factors(like ventilation characteristics, etc.) related to the indoor environment. The results are as follows. The remodeling elements generally included the changing of lighting fixtures and finishing materials in all the spaces, the integration of the balcony into the children's room, the installation of furniture in the kitchen and the entrance, the changing storage furnitures and equipments in the bathroom. The average levels of each unit of relative humidity, $CO_2$, TVOC, HCHO, equivalent noise level, and illumination were proved to be on the whole in inadequate condition. The factors that affect these indoor elements were classified as remodeling factors (remodeling amounts, extent balcony integration, and lighting fixture exchange), ventilation characteristics, and living factors. According to these results, this research proposed the guidelines for the indoor environment in apartment remodeling projects.

Optical Analysis and Experimental Method for Design of Radiative Thermal Reflector (복사열 반사판의 설계를 위한 광학적 해석 및 실험기법)

  • Jung, Hae-Yong;Song, Tae-Ho;Yoo, Seung-Yeol
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
    • /
    • v.20 no.8
    • /
    • pp.563-569
    • /
    • 2008
  • Radiative, heating is suitable for outdoor heating system in windy and cold seasons. Optimal design of the reflector is very important to maximize heat transfer to a specific target area in the open space. The geometrical optical theory can be applied to analyze efficiency of the reflector. Commercial ray tracing computer programs are available only for limited geometries of the reflector. Alternatively, it may be designed and analyzed through an approximated simple lens theory. Two types of reflectors are analyzed using either of these methods. The key issue in this paper is to propose a new illumination experimental method for determination of the radiative efficiency. Optical light source and illuminometer are employed. The calculated efficiency of the reflector is compared with experimental one for checking the reliability. The relative errors between the experimental and analytical results are less than 5%, which proves the validity of this method. Based on these methodologies, a practical reflector and heating lamp unit is developed.

A Study on the Indoor Air Pollution of Singing Room and PC Room (노래방과 컴퓨터 게임방 내의 실내공기오염에 관한 연구)

  • 이주상;원정일;이철민;김윤신
    • Journal of environmental and Sanitary engineering
    • /
    • v.17 no.3
    • /
    • pp.67-74
    • /
    • 2002
  • Nowadays, a new word called SBS(sick building syndrome) has been come into existence. Since most people spend a large majority of their time indoors, indoor air may affect human health more than outdoor air. This outline survey was carried out to investigate the extent of indoor air pollution in singing room and PC room. The concentrations of major indoor air pollutants(carbon dioxide, total suspended particulate, airborne microbes) and Thermocircumstance(temperature, relative humidity, intensity of illumination) were observed from October 1 to 31, 2001. As results of the survey, the mom values of thermocircumstance in singing room and PC room were $22.1^{\circ}C$ of temperature, 37.1% of humidity, 75 Lux of intensity of illumination and $22.0^{\circ}C$ of temperature, 52.6% of humidity, 135 Lux of intensity of illumination, respectively. The mean concentrations of carbon dioxide were 1589 ppm in singing room and 615 ppm in PC room, respectively The concentrations of carbon dioxide in singing room were higher than the indoor environmental standard of the first clause of Article 45 of public utilization service which is showed at public hygiene of the Ministry of Health and Social Affairs. The mean concentrations of total suspended particulate were $0.33{\;}mg/\textrm{m}^3$ in singing room and $0.57{\;}mg/\textrm{m}^3$ in PC room respectively. The mean concentrations of airborne microbe were $16{\;}CFU/\textrm{m}^3$ in singing room and $12{\;}CFU/\textrm{m}^3$ in PC room, respectively.

Characteristics of Damage on Photosensor Irradiated by Intense Illumination : Thermal Diffusion Model (고섬광에 노출된 광센서의 손상 특성 : 열확산 모델)

  • Kwon, Chan-Ho;Shin, Myeong-Suk;Hwang, Hyon-Seok;Kim, Hong-Lae;Kim, Seong-Shik;Park, Min-Kyu
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.15 no.2
    • /
    • pp.201-207
    • /
    • 2012
  • Pulsed lasers at the 613 nm and 1064 nm wavelengths on nanoseconds have been utilized to characterize the damage on Si photodiode exposed to intense illumination. Morphological damages and structural changes at sites on the photodiode irradiated during microseconds of laser pulses were analyzed by FE-SEM images and XRD patterns, respectively. The removal of oxide coating, ripple, melting marks, ridges, and crater on photodiodes were definitely observed in order of increasing the pulse intensities generated above the damage threshold. Then, the degradation in photosensitivity of the Si photodiode irradiated by high power density pulses was measured as a function of laser irradiation time at the various wavelengths. The free charge carrier and thermal diffusion mechanisms could have been invoked to characterize the damage. The relative photosensitivity data calculated using the thermal diffusion model proposed in this paper have been compared with the experimental data irradiated above the damage threshold.

Analysis of the Thermal Environment in the Laying House (산란계사내부 열환경 분석)

  • Kim Y. B.;Lee S. K.;Kim S. T.;La W. J.;Chang H. H.
    • Journal of Animal Environmental Science
    • /
    • v.11 no.3
    • /
    • pp.177-188
    • /
    • 2005
  • In this study, the thermal environmental factors in a layer f(arm such as dry bulb temperature, relative humidity, black globe temperature and illumination intensity were measured and analyzed to serve as basis for effective design and plan of poultry houses. The correlation analysis between the different factors was also done. Heat Index as measure of the thermal stress was also calculated and analyzed. A $1,000m^2$ laying house, 4 meters high with 52,000 layers in six-stage type cages was used in the measurement of the different environmental parameters. The results were as follows; 1. The temperature of the inside air and materials was directly related to the increase in aerial temperature based on the dry-bulb, black globe temperature reading. The correlation factor of the outside to inside air based on dry bulb setting was very significant at 0.927 The dry bulb temperature for inside temperature ranged from $19.9\~28.8^{\circ}C\;with\;SD+2.2^{\circ}C$ while that of the outside air was $16.2\~33.1^{\circ}C,\;SD+3.5^{\circ}C$. In addition, the temperature of the inside air was very stable. 2. The black globe temperature of the inside air ranged from $20.1\~28.8^{\circ}C,\;SD+2.3^{\circ}C$ while that of the outside air was $16.2\~47.5^{\circ}C,\;SD+6.0^{\circ}C$. 3. The relative humidity of the outside and inside air was $72.4\~100\;and\;50.2\~85.6\%$ with an average of $89.2\;and\;71.7\%$, respectively. 4. The illumination intensity in the laying house was less than 7 lux, with an average of $1.2\~2.5lux$ relative to height indicating that the laying house was well isolated from outside radiation. 5. The heat index of the inside air of the laying house had a high variation from $20.5^{\circ}C,\;SD+2.5^{\circ}C$ while that of the outside air was $13.1\~45.5^{\circ}C$, with an average of $21.6^{\circ}C,\;SD+6.3^{\circ}C$.

  • PDF

Simultaneous measurement of in-plane and out-of-plane displacement using holographic interferometry (홀로그래피 간섭계를 이용한 횡변위와 종변위의 동시 측정)

  • 김달우;임부빈
    • Korean Journal of Optics and Photonics
    • /
    • v.8 no.4
    • /
    • pp.267-276
    • /
    • 1997
  • We set up a four-wave holographic interferometer using a symmetric dual-beam illumination which is to measure in-plane and out-of-plane displacement simultaneously. In order to acquire the displacement phase map we applied the phase-shifting method and removed the noise of the phase map with least-squares fitting. In this approach the access to information relative to both the difference and sum of phases existing in the two arms of four-wave holographic interferometer was allowed. As a result, in-plane and out-of-plane displacement was measured to the accuracy of λ/40 and λ/100, respectively at λ=632.8nm

  • PDF

Automatic Colorectal Polyp Detection in Colonoscopy Video Frames

  • Geetha, K;Rajan, C
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.17 no.11
    • /
    • pp.4869-4873
    • /
    • 2016
  • Colonoscopy is currently the best technique available for the detection of colon cancer or colorectal polyps or other precursor lesions. Computer aided detection (CAD) is based on very complex pattern recognition. Local binary patterns (LBPs) are strong illumination invariant texture primitives. Histograms of binary patterns computed across regions are used to describe textures. Every pixel is contrasted relative to gray levels of neighbourhood pixels. In this study, colorectal polyp detection was performed with colonoscopy video frames, with classification via J48 and Fuzzy. Features such as color, discrete cosine transform (DCT) and LBP were used in confirming the superiority of the proposed method in colorectal polyp detection. The performance was better than with other current methods.

Localization of Mobile Robot Using Color Landmark mounted on Ceiling (천장 부착 컬러 표식을 이용한 이동로봇의 자기위치추정)

  • Oh, Jong-Kyu;Lee, Chan-Ho
    • Proceedings of the KIEE Conference
    • /
    • 2001.11c
    • /
    • pp.91-94
    • /
    • 2001
  • In this paper, we proposed localization method of mobile robot using color landmark mounted on ceiling. This work is composed 2 parts : landmark recognition part which finds the position of multiple landmarks in image and identifies them and absolute position estimation part which estimates the location and orientation of mobile robot in indoor environment. In landmark recognition part, mobile robot detects artificial color landmarks using simple histogram intersection method in rg color space which is insensitive to the change of illumination. Then absolute position estimation part calculates relative position of the mobile robot to the detected landmarks. For the verification of proposed algorithm, ceiling-orientated camera was installed on a mobile robot and performance of localization was examined by designed artificial color landmarks. As the result of test, mobile robot could achieve the reliable landmark detection and accurately estimate the position of mobile robot in indoor environment.

  • PDF