• Title/Summary/Keyword: color area-ratio

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SOOT YIELD OF TURBULENT PREMIXED PROPANE-OXYGEN-INERT GAS FLAMES IN A CONSTANT-VOLUME COMBUSTOR AT HIGH PRESSURES

  • Bae, M.W.;Bae, C.W.;Lee, S.K.;Ahn, S.W.
    • International Journal of Automotive Technology
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    • v.7 no.4
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    • pp.391-397
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    • 2006
  • The soot yield has been studied by a premixed propane-oxygen-inert gas combustion in a specially designed disk-type constant-volume combustion chamber to investigate the effect of pressure, temperature and turbulence on soot formation. Premixtures are simultaneously ignited by eight spark plugs located on the circumference of chamber at 45 degrees intervals in order to observe the soot formation under high temperature and high pressure. The eight converged flames compress the end gases to a high pressure. The laser schlieren and direct flame photographs with observation area of 10 mm in diameter are taken to examine the behaviors of flame front and gas flow in laminar and turbulent combustion. The soot volume fraction in the chamber center during the final stage of combustion at the highest pressure is measured by the in-situ laser extinction technique and simultaneously the corresponding burnt gas temperature by the two-color pyrometry method. The changes of pressure and temperature during soot formation are controlled by varying the initial charging pressure and the volume fraction of inert gas compositions, respectively. It is found that the soot yield increases with dropping the temperature and raising the pressure at a constant equivalence ratio, and the soot yield in turbulent combustion decreases as compared with that in laminar combustion because the burnt gas temperature increases with the drop of heat loss for laminar combustion.

2D Spatial-Map Construction for Workers Identification and Avoidance of AGV (AGV의 작업자 식별 및 회피를 위한 2D 공간 지도 구성)

  • Ko, Jung-Hwan
    • Journal of the Institute of Electronics and Information Engineers
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    • v.49 no.9
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    • pp.347-352
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    • 2012
  • In this paper, an 2D spatial-map construction for workers identification and avoidance of AGV using the detection scheme of the spatial coordinates based on stereo camera is proposed. In the proposed system, face area of a moving person is detected from a left image among the stereo image pairs by using the YCbCr color model and its center coordinates are computed by using the centroid method and then using these data, the stereo camera embedded on the mobile robot can be controlled for tracking the moving target in real-time. Moreover, using the disparity map obtained from the left and right images captured by the tracking-controlled stereo camera system and the perspective transformation between a 3-D scene and an image plane, depth map can be detected. From some experiments on AGV driving with 240 frames of the stereo images, it is analyzed that error ratio between the calculated and measured values of the worker's width is found to be very low value of 2.19% and 1.52% on average.

Reproductive Ecology of Gobiobotia brevibarba (Cyprinidae) (돌상어 Gobiobotia brevibarba (Cyprinidae)의 산란 생태)

  • Choi, Jae-Suk;Byeon, Hwa-Kun;Kwon, Oh-Kil
    • Korean Journal of Ichthyology
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    • v.13 no.2
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    • pp.123-128
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    • 2001
  • The reproductive ecology of Gobiobotia brevibarba was investigated at Hongchen River of Bangokri, Seomyon, Hongcheongun, Kangwondo, from March 1999 to February 2000. The favorite habitat was a stretch of river with fast flow and a stream bed mostly covered with cobbles and pebbles. The spawning ground was a riffle area 20~50 cm deep, with a current velocity of 0.6~1.3 m/sec, and a bottom consisting of cobble and boulder. The sex ratio of female to male was 1 : 0.86. Peak spawning season was May when water temperatures rose to $18{\sim}20^{\circ}C$. Male and females became sexually mature when they attained more than 40 mm and 50 mm in body length, respectively. The average number of eggs in the ovary was $2,040{\pm}400.57$ and the egg diameter was $1.98{\pm}0.06\;mm$. The matured eggs were demersal, spherical, and dimmed light yellow in color.

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Production of Structured Lipid Containing Capric and Conjugated Linoleic Acids and Studies of Physicochemical Characteristics (Capric acid와 conjugated linoleic acid를 함유한 재구성 지질의 합성 및 특성연구)

  • Shin, Jung-Ah;Lee, Ki-Teak
    • Korean Journal of Food Science and Technology
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    • v.36 no.4
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    • pp.537-541
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    • 2004
  • Based on reaction time and substrate molar ratio, structured lipid (SL-corn) was produced at 1:2:2(corn oil/capric acid/CLA) and 4% immobilized lipase from Rhizomucor miehei (RM IM). Reaction was carried out for 24 hr at $55^{\circ}C$ in 1-L stirred-batch reactor. After reaction, 13.3 mol% capric acid and 8.9%, CLA were incorporated into corn oil. Iodine and saponification values of SL-corn were 68 and 202, respectively. Tocopherol content decreased after reaction (about 39%). SL-corn showed more yellowish color than corn oil (p<0.05). Reversed-phase HPLC indicated triacylglycerol species containing capric acid in SL-corn resulted in faster crystallization than that of corn oil.

Changes in Rheological Properties of Neungee(Sarcodon aspratus) during Dehydration (능이버섯의 건조과정 중 물성의 변화)

  • 우관식;정헌상;이희봉;최원석;이준수
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.33 no.7
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    • pp.1230-1236
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    • 2004
  • This study was conducted to investigate the changes in physical properties of the Neungee (Sarcodon aspratus) during dehydration and rehydration. The drying of the sample was completed within 4 hours at 5$0^{\circ}C$ with the air velocity of 1.5 m/s. The reduction in the thickness of the sample were two-fold compared with those in the surface area of the sample. During the drying period, the values of compression distance, break down, deformation rate, distortion, alleviation rate and softness decreased, whereas the values of hardness and alleviation time increased. However, the values of surrender were not changed. The color of the sample during the drying was changed to black with decreased L, a, and b values. The rehydration rate increased rapidly during first 60 min and remained constant after that. The recovery ratio after rehydration of the dried sample was about 30% and the rheological properties recovered about 44%.

Study on Clothing Style Preference according to Cosmetic Surgery Parts and Clothing Behavior Group: Based on Cosmetic Surgery Experienced by Women in their 20s and 30s (미용성형부위 및 의복행동그룹에 따른 의복스타일선호에 관한 연구: 미용성형을 경험한 20~30대 여성을 중심으로)

  • Lee, Jungeun;Choi, Jeongwook
    • Journal of Fashion Business
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    • v.18 no.1
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    • pp.182-198
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    • 2014
  • The main purposes of this study is to evaluate clothing behaviors according to cosmetic surgery parts and to research how the clothing style preference is expressed depending on each clothing behavior group. This study focuses on women in their 20s and 30s living in Seoul and Gyeonggi area whom have cosmetic surgery experiences. From the women being evaluated, the following groups are divided and then surveyed with equal frequency and ratio: 'facial surgery', 'face contour surgery', 'breast surgery', and 'body figure revision'. When comparing the changes in clothing style preferences before and after the cosmetic surgery, they prefer silhouettes which show body shapes, diversity of color tones, and more overall exposing preferences. After investigating the preferred clothing styles based on cosmetic surgery parts, it is being analyzed that body exposure is more aggressively expressed upon after taking the surgery because the self satisfaction is increased according to the changes in their body shapes after the surgery. Lastly, after looking into the cosmetic surgery and the clothing preferences styles of each clothing behavior group, there seems to be more breast surgeries and body figure revisions for aggressive and extroverted characters: the sex-appeal and mood switching type. It is also being analyzed that facial surgeries are more common in the passive group: information collection, trend alignment, and beauty preference. Such results are also reflected in clothing preferences styles: the biggest change is shown in the aggressive and extroverted group, the sex-appeal types.

A Study on Digital Control Method of LED Luminance (LED 휘도의 디지털 제어 방식에 관한 연구)

  • Kang, Shin-Ho;Ryeom, Jeong-Duk
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.24 no.1
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    • pp.28-34
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    • 2010
  • The pulse width modulation(PWM) method has been generally used as conventional method controlling luminance of LED(light emitting diode). PWM method as analog method with a relation that duty ratio of LED be proportional to luminance has weak point that it is not compatible with digital method of communication etc. In this paper, a experiment is conducted which the luminance of RGB LED be controlled by digital method. For this, the LED digital control system is developed which consist of LED driving circuits and digital logic circuits. By controlling the number of pluses on RGB LED versus digital input, various lighting colors is implemented and digital codes are optimized in order that measured x, y chromaticity coordinates of lighting colors are comprised in the CIE chromaticity coordinates area of targeted lighting colors. The result of this study can be utilized usefully in research on implementing full color by using remote control of LED lamp with digital communication.

Synthesis of New Blue OLEDs with Biphenyl Structure and Relationship between EL Efficiency and Drift Mobility (Biphenyl 구조를 가진 새로운 청색 유기 발광 재료의 합성 및 EL효율과 이동도의 관계에 대한 연구)

  • Lee, Tae-Hoon;Ryu, Jung-Yi;Kim, Tae-Hoon;Nam, Jang-Hyun;Park, Seong-Soo;Son, Se-Mo
    • Journal of the Korean Graphic Arts Communication Society
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    • v.22 no.2
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    • pp.179-198
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    • 2004
  • Organic electroluminescent devices are light-emitting diodes in which the active materials consist entirely of organic materials. Recently, many fluorescent organic materials have been reported and the study on synthesis and application of new organic light-emitting materials has been demanded. This paper reports the optical and electrical characteristics of OLEDs using novel polymers containing biphenyl structure. First, Optical properties of novel light-emitting biphenyl derivatives doped with poly(9-vinyl carbazole)(PVK) and emitted blue, bluish green color, which is attributed to the overlap area between PL spectrum of host(PVK) and absorption spectra of guests(polymer). This is correspondent with F$\"{o}$rster energy transfer process in the blends. And, OLED devices were fabricated using poly (3,4-ethylenedioxy thiophene) (PEDOT) as a hole injection material and tris-(8-hydroxyquinoline) aluminum ($Alq_3$) as an electron transporting material. EL devices fabricated as ITO/PEDOT/PVK doped with biphenyl derivatives/$Alq_3$/Li:Al and I-V-L chatacteristics and emitting efficiency of EL devices were examined. Finally, the drift mobility of PVK doped with biphenyl derivatives and $Alq_3$ were measured by TOF technique varying applied electric field. EL efficiency was increased as the ratio of hole mobility of PVK doped with biphenyl derivatives and electron mobility of $Alq_3$ was close to one.

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Face Region Tracking Improvement and Hardware Implementation for AF(Auto Focusing) Using Face to ROI (얼굴을 관심 영역으로 사용하는 자동 초점을 위한 얼굴 영역 추적 향상 방법 및 하드웨어 구현)

  • Jeong, Hyo-Won;Ha, Joo-Young;Han, Hag-Yong;Yang, Hoon-Gee;Kang, Bong-Soon
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.14 no.1
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    • pp.89-96
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    • 2010
  • In this paper, we proposed a method about improving face tracking efficiency of face detection for AF system using the faces to the ROI. The conventional face detection system detecting faces based skin color uses the ratio of skin pixels of the present frame to detected face regions of the past frame to track the faces. The tracking method is superior in the stability of the regions but it is inferior in the face tracking efficiency. We proposed a face tracking method using the area of the overlapping region in the detected face regions of the past frame and the present frame to improve the tracking efficiency. The proposed face tracking efficiency demonstration was performed by making a film of face detection with face tracking in real-time and using the moving traces of the detected faces.

Semi-Automated Extraction of Geographic Information using KOMPSAT 2 : Analyzing Image Fusion Methods and Geographic Objected-Based Image Analysis (다목적 실용위성 2호 고해상도 영상을 이용한 지리 정보 추출 기법 - 영상융합과 지리객체 기반 분석을 중심으로 -)

  • Yang, Byung-Yun;Hwang, Chul-Sue
    • Journal of the Korean Geographical Society
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    • v.47 no.2
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    • pp.282-296
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    • 2012
  • This study compared effects of spatial resolution ratio in image fusion by Korea Multi-Purpose SATellite 2 (KOMPSAT II), also known as Arirang-2. Image fusion techniques, also called pansharpening, are required to obtain color imagery with high spatial resolution imagery using panchromatic and multi-spectral images. The higher quality satellite images generated by an image fusion technique enable interpreters to produce better application results. Thus, image fusions categorized in 3 domains were applied to find out significantly improved fused images using KOMPSAT 2. In addition, all fused images were evaluated to satisfy both spectral and spatial quality to investigate an optimum fused image. Additionally, this research compared Pixel-Based Image Analysis (PBIA) with the GEOgraphic Object-Based Image Analysis (GEOBIA) to make better classification results. Specifically, a roof top of building was extracted by both image analysis approaches and was finally evaluated to obtain the best accurate result. This research, therefore, provides the effective use for very high resolution satellite imagery with image interpreter to be used for many applications such as coastal area, urban and regional planning.

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