• Title/Summary/Keyword: Glow Effect

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Traffic Light Recognition Based on the Glow Effect at Night Image (야간 영상에서의 빛 번짐 현상을 이용한 교통신호등 인식)

  • Kim, Min-Ki
    • Journal of Korea Multimedia Society
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    • v.20 no.12
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    • pp.1901-1912
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    • 2017
  • Traffic lights at night are usually framed in the image as bright regions bigger than the real size due to glow effect. Moreover, the colors of lighting region saturate to white. So it is difficult to distinguish between different traffic lights at night. Many related studies have tried to decrease the glow effect in the process of capturing images. Some studies drastically decreased the shutter time of the camera to reduce the adverse effect by the glow. However, this makes the video too dark. This study proposes a new idea which utilizes the glow effect. It examines the outer radial region of traffic light. It presents an algorithm to discriminate the color of traffic light by the analysis of the outer radial region. The advantage of the proposed method is that it can recognize traffic lights in the image captured by an ordinary black box camera. Experimental results using seven short videos show the performance of traffic light recognition reporting the precision of 96.4% and the recall of 98.2%. These results show that the proposed method is valid and effective.

Effect of Secondary Electron Emission on the Glow Discharges with Different Electrode Gaps (서로 다른 전극간격에서 이차전자 방출이 글로우 방전에 미치는 영향에 관한 연구)

  • Seo, Jeong-Hyun;Kang, Kyung-Doo
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.58 no.4
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    • pp.777-782
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    • 2009
  • In this paper, the effect of the secondary electron emission coefficient of Xe ion on glow discharge was examined by ID numerical simulation. The simulation was performed for two distinct structures, short and long gaps. The features of the glow discharges in the both structures, firing and sustain voltages, luminance, and efficiency, were analyzed at various secondary electron emission coefficient of Xe ion.

Optimal Annealing of Natural Beryl for Thermoluminescent Dosimetry

  • Moon, Philip S.
    • Nuclear Engineering and Technology
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    • v.6 no.1
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    • pp.3-8
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    • 1974
  • The annealing of natural beryl powder used for the thermoluminescent dosimetry was investigated in order to eliminate effect of previous exposure. Through the glow curve analysis, the optimal annealing treatment was found to be one hour annealing at 145$0^{\circ}C$, but annealing for one hour at 55$0^{\circ}C$ was sufficient for reuse of natural beryl powder. There are two distinguished glow peaks at $65^{\circ}C$ and 20$0^{\circ}C$ of heating temperature during readout process. The $65^{\circ}C$ glow peak fades away rapidly, but the 20$0^{\circ}C$ glow peak remains very stable. It is, therefore, quite feasible to use the 20$0^{\circ}C$ glow peak for thermoluminescent dosimetry.

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Suppression of Glow Corona on Streamer and Influence of Thin Wire on its Inception

  • Sima, Wenxia;Fan, Shuochao;Yang, Qing;Wang, Qi
    • Journal of Electrical Engineering and Technology
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    • v.10 no.4
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    • pp.1759-1764
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    • 2015
  • Glow corona is a kind of streamer-free corona that can suppress upward leaders in transmission lines. Thus, it has good application potential in lightning protection. This paper investigates its corona characteristics. The suppression characteristic of glow corona on streamer is studied in air gap under negative DC voltage by wrapping thin wires on the electrode. The effect of thin wire winding patterns on the gap breakdown voltage is analyzed. Results are considered to be attributed to the inception condition of glow corona. Thus an inception test of glow corona is also conducted, and the inception voltage is obtained. Results show that the inception voltage decreases with short winding pitch. Thus an investigation on the inception of glow corona influenced by thin wire is conducted, and an influential factor is proposed to evaluate the influence. The inception regular of thin wire glow corona presented in this paper has certain reference value for the application of glow corona in transmission lines.

An Experimental Approach for Verifying the Effect of Scattered Gamma-rays on the “Before Glow”in a Thermoluminescent Glow Curve

  • Jun, Jae-Shik;Lee, Hee-Yong
    • Nuclear Engineering and Technology
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    • v.4 no.1
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    • pp.3-10
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    • 1972
  • In order to verify the contribution of scattered photons in a restricted gamma-cell as a cause of the“before glow”on a thermoluminescent glow curve of natural quartz, the ratio of the scattered to primary radiation contributions (S/P) in the cell is measured and the relationship between the effective“before glow”height ( $h_{b}$) and S/P ratio is quantitatively investigated. The result shows quite good linear relationship between them with a correlation coefficient of +0.9, which possibly suggests that the electrons originally released by the photons of reduced energy are trapped in the shallower traps. Moreover, the ratios of $h_{b}$ to total glow area (At) and of effective “before glow”area (Ab) to At are also examined to see the relationships between S/P and each of them, respectively. The relationships are represented by exponential functions in the region of S/P greater than 0.035. Finally, the exposure limit for re-use of the natural quartz as a TLD was found to be approximately 10$^{5}$ R by analyzing total thermoluminescent output and corresponding exposure dose.ose.

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Thermoluminescence of $MgCl_2$-Activated LiF Powder (불순물 $MgCl_2$를 첨가한 LiF 분말의 열형광)

  • 이계철;이상수
    • Nuclear Engineering and Technology
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    • v.2 no.4
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    • pp.269-272
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    • 1970
  • Thermoluminescence (TL) from LiF powder of purity 99.98 % was accomplished and this TL intensity showed glow peaks at 12$0^{\circ}C$, 22$0^{\circ}C$ and 30$0^{\circ}C$. Sintered LiF powder which has an activation of 2% proportion by weight of MgC1$_2$show strong increased TL and this characteristic of the glow curve was investigated precisely. LiF which is used in TL dosimetry has been known to have electrons caused by impurities such as Mg, Mn, etc. This experiment shows that Mg, one of the impurities, is definitely diffused through LiF crystals. The effects of sintering time were detected in this glow curve and it was confirmed that MgC1$_2$also has a TL effect.

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Optical Sensitivity of TL Glow Peaks Separated Using Computerized Glow Curve Deconvolution for RTL Quartz

  • Kim, Myung-Jin;Kim, Ki-Bum;Hong, Duk-Geun
    • Journal of Radiation Protection and Research
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    • v.43 no.3
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    • pp.114-119
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    • 2018
  • Background: The retrospective dosimetry using RTL quartz can be improved by information for an optical sensitivity of sample connected with the equivalent dose determination. Materials and Methods: The quartz sample from a volcanic rock of Japan was used. After correcting the thermal quenching effect, RTL peaks of quartz were separated by the CGCD method cooperated with the general order kinetics. The number of overlapped glow peaks were ascertained by the $T_m-T_{stop}$ method. The optical sensitivity was examined by comparing the change of intensity on RTL glow peaks measured after exposure to light from a solar simulator with various illumination times. Results and Discussion: Seven glow peaks appeared to be overlapped on the RTL glow curve. The general order kinetics model was appropriate to separate glow peaks. After exposure to light from a solar simulator from a few minutes to 416 hr, the signals for peaks P4 and P5 decayed following the form of $f(t)=a_1e^{-{\lambda}1t}$, while the signals for peaks P6 and P7 decayed by the form of $f(t) = a_1e^{-{\lambda}1t}+a_2e^{-{\lambda}2t}+a_3e^{-{\lambda}3t}$. Conclusion: For dosimetric peaks, the times taken to reduce the RTL signal to half of its initial value were 70 sec for the peak P4, 54 s for the peak P5, 9,840 sec for the peak P6 and 26,580 sec for the peak P7, respectively. We conclude that the optical sensitivity of peaks P4, and P5 gives much higher than that of peaks P6 and P7.

Effect of Discharge Gas on the Electrical Characteristics of the Glow Discharge Plasma for the Gas Chromatographic Detector (글로우방전 가스크로마토그라프 검출기에서 방전가스의 영향)

  • 박현미;강종성;김효진
    • YAKHAK HOEJI
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    • v.39 no.5
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    • pp.480-486
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    • 1995
  • The change in discharge current of a glow discharge has been shown the potential sensitive detector for gas chromatography. To investigate the effect of carrier gas on the electrical characteristics of the discharge and the peak response, the discharge pressure, gas flow rate, and discharge gap have been studied. The discharge gas included the Ar, He, and N$_{2}$. The gas flow rate has been found one of the important parameters to affect both the electrical characteristics and the peak response.

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Current, flow rate and pressure effects in a Gas-Jet-assisted Glow Discharge source (Gas-Jet-assisted Glow Discharge에서 전류, 가스 흐름 속도, 압력에 따른 영향 연구)

  • Lee, Gaeho;Kim, Dongsoo;Kim, Eunhee;Kang, Seongshik;Park, Minchun;Song, Haeran;Kim, Hasuck;Kim, Hyojin
    • Analytical Science and Technology
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    • v.7 no.4
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    • pp.483-492
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    • 1994
  • Direct solid analysis of various kinds of metal samples has been conducted by glow discharge. In this laboratory, the gas-jet assisted glow discharge(GJGD) device has been developed and characterized. The effect of changes in applied current, cell pressure and flow rate on atomic emission signals obtained from a jet-assisted cathodic sputtering was investigate. The emission intensities of Cu, Zn, and Ar were measured. They were increased with the current. But the intensities were decreased by increasing the flow rate of argon due to the diffusion and transportation of particles into plasma. By increasing the pressure of the cell, the intensities were greatly decreased because of enhancement of redeposition onto the surface of the sample.

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ANALYSIS OF THE LiF:Mg,Cu,Si TL AND THE LiF:Mg,Cu,P TL GLOW CURVES BY USING GENERAL APPROXIMATION PLUS MODEL

  • Chang, In-Su;Lee, Jung-Il;Kim, Jang-Lyul;Oh, Mi-Ae;Chung, Ki-Soo
    • Journal of Radiation Protection and Research
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    • v.34 no.4
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    • pp.155-164
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    • 2009
  • In this paper, we used computerized glow curve deconvolution (CGCD) software with several models for the simulation of a TL glow curve which was used for analysis. By using the general approximation plus model, parameters values of the glow curve were analyzed and compared with the other models parameters (general approximation, mixed order kinetics, general order kinetics). The LiF:Mg,Cu,Si and the LiF:Mg,Cu,P material were used for the glow curve analysis. And we based on figure of merits (FOM) which was the goodness of the fitting that was monitored through the value between analysis model and TLD materials. The ideal value of FOM is 0 which represents a perfect fit. The main glow peak makes the most effect of radiation dose assessment of TLD materials. The main peak of the LiF:Mg,Cu,Si materials has a intensity rate 80.76% of the whole TL glow intensity, and that of LiF:Mg,Cu,P materials has a intensity rate 68.07% of the whole TL glow intensity. The activation energy of LiF:Mg,Cu,Si was analyzed as 2.39 eV by result of the general approximation plus(GAP) model. In the case of mixed order kinetics (MOK), the activation energy was analyzed as 2.29 eV. The activation energy was analyzed as 2.38 eV by the general order kinetics (GOK) model. In the case of LiF:Mg,Cu,P TLD, the activation energy was analyzed as 2.39 eV by result of the GAP model. In the case of MOK, the activation energy was analyzed as 2.55 eV. The activation energy was analyzed as 2.51 eV by the GOK model. The R value means different ratio of retrapping-recombination. The R value of LiF:Mg,Cu,Si TLD main peak analyzed as $1.12\times10^{-6}$ and $\alpha$ value analyzed as $1.0\times10^{-3}$. The R of LiF:Mg,Cu,P TLD analyzed as $7.91\times10^{-4}$, the $\alpha$ value means different ratio of initial thermally trapped electron density-initial trapped electron density (include thermally disconnected trap electrons density). The $\alpha$ value was analyzed as $9.17\times10^{-1}$ which was the difference from LiF:Mg,Cu,Si TLD. The deep trap electron density of LiF:Mg,Cu,Si was higher than the deep trap electron density of LiF:Mg,Cu,P.