• Title/Summary/Keyword: Adaptive Contrast

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Adaptive Color Correction Method to Monitor in Color Laser Printer (모니터에 적응적인 칼라 레이저 프린터의 색 변환 방법)

  • Jang, In-Su;Son, Chang-Hwan;Kim, Kyung-Man;Ha, Yeong-Ho
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.47 no.4
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    • pp.63-68
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    • 2010
  • The Color Management System in recent printers adopts ICC profiles for both monitors and printers. However, the ICC profile doesn't contain the characteristics of reproduced color on each monitor, because the color on each monitor is changed by user adjustment such as color temperature, brightness, and contrast adjustment. It is also depended on the backlight type and lifetime. As a result, unwanted color is reproduced on the printed paper, not like that on the monitor. To overcome the color difference between monitors and printers, it is needed to control the information of ICC profile. That is, first, the ICC profile is generated by the measurement of monitors having user set, then, through the CMS, the color on monitors can be produced on printed paper. However, it is difficult to apply the above system for normal users due to absence of measuring equipment and time consuming process. Therefore, this paper proposes a novel color matching technique based on the estimation of condition for each monitor having user set. The estimation is performed by a simple comparison visual test using a test image on printed paper and monitor. Then, the condition of monitor is applied to the ICC profile. As a result, the new ICC profile contains the color difference between user monitor and printer. The experimental results show the printed images using our proposed method have almost similar color with those on monitors.

Design of Real-Time PreProcessor for Image Enhancement of CMOS Image Sensor (CMOS 이미지 센서의 영상 개선을 위한 실시간 전처리 프로세서의 설계)

  • Jung, Yun-Ho;Lee, Joon-Hwan;Kim, Jae-Seok;Lim, Won-Bae;Hur, Bong-Soo;Kang, Moon-Gi
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.38 no.8
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    • pp.62-71
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    • 2001
  • This paper presents a design of the real-time digital image enhancement preprocessor for CMOS image sensor. CMOS image sensor offers various advantages while it provides lower-quality images than CCD does. In order to compensate for the physical limitation of CMOS sensor, the spatially adaptive contrast enhancement algorithm was incorporated into the preprocessor with color interpolation, gamma correction, and automatic exposure control. The efficient hardware architecture for the preprocessor is proposed and was simulated in VHDL. It is composed of about 19K logic gates, which is suitable for low-cost one-chip PC camera. The test system was implemented on Altera Flex EPF10KGC503-3 FPGA chip in real-time mode, and performed successfully.

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p53 Nuclear Accumulation as a Possible Biomarker for Biological Radio-dosimetry in Oral Mucosal Epithelial Cells

  • Kim, Youn-Young;Kim, Jong-il;Kim, Jin;Yook, Jong-In;Kim, The-Hwan;Son, Young-Sook
    • BMB Reports
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    • v.34 no.2
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    • pp.123-129
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    • 2001
  • Cellular response to ionizing radiation is affected by cell types, radiation doses, and post-irradiation time. Based on the trypan blue dye exclusion assay in normal oral mucosal cells (OM cells), a 48 h post-irradiation was sufffcient and an adequate time point for the evaluation of radiation sensitivity Its $LD_{50}$ was approximately 1.83 Gy To investigate possible biomarkers useful for the biological radiodosimetry of normal epithelial cells (p53, c-fos, cyclin D1, cdc-2, pRb) EGF receptor phosphorylation and Erk activation were evaluated at different radiation doses and different post-irradiation times. From 0.5 Gy, p53 was accumulated in the nucleus of basal cells of the OM raft culture at 4 h post-irradiation and sustained up to 24 h post-irradiation, which suggests that radiation-induced apoptosis or damage repair was not yet completed. The number of p53 positive cells and biosynthesis of p53 were correlated with radiation doses. Both cyclin D1 and c-fos were only transiently induced within 1 h post-irradiation. Cyclin D1 was induced at all radiation doses. However, cfos induction was highest at 0.1 Gy, approximately 7.3 fold more induction than the control, whose induction was reduced in a reverse correlation with radiation dose. The phosphorylation pattern of cdc-2 and pRb were unaffected by radiation. In contrast to A431 tails overexpressing the EGF receptor approximately 8.5 fold higher than normal epithelial, the OM cells reduced the basal level of the EGF receptor phosphorylation in a radiation dose dependent fashion. In conclusion, among radiation-induced biomolecules, the p53 nuclear accumulation may be considered for the future development of a useful marker far biological radiodosimetry in normal epithelial tissue since it was sustained for a longer period and showed a dose response relationship. Specific c-fos induction at a low dose may also be an important finding in this study It needs to be studied further for the elucidation of its possible connection with the low dose radio-adaptive response.

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Effects of Dissolved Oxygen Level on Avermectin $B_{1a}$ Production by Streptomyces avermitilis in Computer-Controlled Bioreactor Cultures

  • Song, Sung-Ki;Jeong, Yong-Seob;Kim, Pyeung-Hyeun;Chun, Gie-Taek
    • Journal of Microbiology and Biotechnology
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    • v.16 no.11
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    • pp.1690-1698
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    • 2006
  • In order to investigate the effect of dissolved oxygen (DO) level on AVM $B_{1a}$ production by a high yielding mutant of Streptomyces avermitilis, five sets of bioreactor cultures were performed under variously controlled DO levels. Using an online computer control system, the agitation speed and aeration rate were automatically controlled in an adaptive manner, responding timely to the oxygen requirement of the producer microorganism. In the two cultures of DO limitation, the onset of AVM $B_{1a}$ biosynthesis was observed to casually coincide with the fermentation time when oxygen-limited conditions were overcome by the producing microorganism. In contrast, this phenomenon did not occur in the parallel fermentations with DO levels controlled at around 30% and 40% throughout the entire fermentation period, showing an almost growth-associated mode of AVM $B_{1a}$ production: AVM $B_{1a}$ biosynthesis under the environments of high DO levels started much earlier than the corresponding oxygen-limited cultures, leading to a significant enhancement of AVM $B_{1a}$ production during the exponential stage. Consequently, approximately 6-fold and 9-fold increases in the final AVM $B_{1a}$ production were obtained in 30% and 40% DO-controlled fermentations, respectively, especially when compared with the culture of severe DO limitation (the culture with 0% DO level during the exponential phase). The production yield ($Y_{p/x}$), volumetric production rate (Qp), and specific production rate (${\bar{q}}_p$) of the 40% DO-controlled culture were observed to be 14%, 15%, and 15% higher, respectively, than those of the parallel cultures that were performed under an excessive agitation speed (350 rpm) and aeration rate (1 vvm) to maintain sufficiently high DO levels throughout the entire fermentation period. These results suggest that high shear damage of the high-yielding strain due to an excessive agitation speed is the primary reason for the reduction of the AVM $B_{1a}$ biosynthetic capability of the producer. As for the cell growth, exponential growth patterns during the initial 3 days were observed in the fermentations of sufficient DO levels, whereas almost linear patterns of cell growth were observed in the other two cultures of DO limitation during the identical period, resulting in apparently lower amounts of DCW. These results led us to conclude that maintenance of optimum DO levels, but not too high to cause potential shear damage on the producer, was crucial not only for the cell growth, but also for the enhanced production of AVM $B_{1a}$ by the filamentous mycelial cells of Streptomyces avermitilis.

Zooplankton Community Dynamic in Lentic Freshwater Ecosystems in the Nakdong River Basin (낙동강 유역권 내 정수생태계의 동물플랑크톤 군집 동태)

  • Kim, Seong-Ki;Hong, Dong-gyun;Kang, MeeA;Lee, Kyung-Lak;Lee, Hak Young;Joo, Gea-Jae;Choi, Jong-Yun
    • Korean Journal of Environment and Ecology
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    • v.29 no.3
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    • pp.410-420
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    • 2015
  • In order to estimate the influence of environmental factors on zooplankton communities in lentic freshwater ecosystems, 20 reservoirs and wetlands were monitored by season in 2013. A total of 109 species of zooplankton were identified during the study period. Zooplankton assemblage showed a different distribution in its density and diversity in accordance with the seasons. In particular, the density of zooplankton (98 species and 603ind. L-1) was the most in autumn when compared to the other seasons. In order to effectively analyze zooplankton distribution that are affected by various environmental factors, a Self-Organizing Map (SOM) was used, which extracts information through competitive and adaptive properties. A total of 11 variables (8 environment factors and 3 groups of zooplankton) were patterned on to the SOM. Based on a U-matrix, four clusters were identified from the model. Among zooplankton communities, rotifer displayed a positive relationship with water temperature, and cladocerans and copepod were positively related to conductivity, chlorophyll a, and nutrient factor (i. e. TN and TP). In contrast, high dissolved oxygen appeared to have a negative effect on zooplankton distribution. Consequently, the SOM results depicted a clear pattern of zooplankton density clusters partitioned by environmental factors, which play a key role in determining the seasonal distribution of zooplankton groups in lentic freshwater ecosystem.

ALTERATIONS OF BLOOD CELLS AND HEMATOPOIETIC FUNCTION DURING THE EXPERIMENTAL STARVATION I. PRELIMINRY HEMATOLOGICAL OBSERVATION IN THE COURSE OF STARVATION ON RABBITS (실험적(實驗的) 절식(絶食)에 있어서 혈액세포(血液細胞) 및 조혈기능(造血機能)의 변화(變化)에 관(關)한 연구(硏究) 1. 가토(家兎)의 절식경과(絶食經過)에 있어서 예비적(豫備的) 혈액학적(血液學的) 관찰(觀察))

  • Lee, Bang Whan
    • Korean Journal of Veterinary Research
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    • v.1 no.1
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    • pp.1-29
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    • 1961
  • A routine hematological observation in the course of starvation was carried out on eight experimentel1y starved rabbits. They were strictly selected and restricted all of food intake with the exception of optional water intake until death. The body weight of each rabbit on the day before starvation was about 2 kilograms. The results are summarized as follows. 1. The average decrememt ratio of body weight on the terminal day before death was $34.3{\pm}7.5$ per cent with the range from 24.5 to 46.3 per cent. The average life duration until death was $10.25{\pm}2.6$ days, the range being from 6 to 14 days. 2. The decrease in number of reticulocytes with a parallel disappearance of polychromatic erythrocytes in peripheral blood in the course of starvation Was the most remarkable change in erythrocytic series, an evidence suggesting marked restriction of the erythropoietic function on 3rd to 4th day and almost complete suspension in about a week of starvation. 3. Erythrocyte count, hemoglobin content and haematocrit value of peripheral blood, were normal or indicative of slight hemoconcentration. 4. Mean Corpuscular Hemogloin Concentration was slightly higher than normal and Mean Corpuscular Volume tended to be low and no appreciable shifts were observed in Mean Corpuscular Diameter and Price-Jones curve of erythrocytes, while fewer macrocytes than normal were seen. These changes were considered to have resulted from a marked decrease in young erythrocytes in peripheral blood in the course of starvation. 5. Neither poikilccytoses or anisosytosis was observed. 6. Leukopenia was observed in all of 8 starved rabbits. The decrement ratio on the terminal day of starvation was between 13 to 64 per cent. The leukopenia was mainly due to fall of lymphocytes in 6 cases and to fall of neutrophilic leukocytes in the other 2 cases. In many cases, irregular fluctuation of neutrophilic leukocytes in its biological curve were seen in contrast to the relatively smooth changes of lymphocytes. Eosinophilic leukocytes tended to decrease in absolute number especially in later stage of starvation. Little significance in regard to monocytes and basophilic leukocytes in this study was discussed. 7. Proplasma cells, rarely plasma cells, appeared with a tendency to increase in number at later stage of starvation. 8. The most characteristic changes on circulating blood cells in complete starvation of rabbits were the leukoponia and failure of regeneration of erythroctes. These changes were considered as adaptive phenomena in response to the catabolic consumption of body constituents.

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Color Image Rendering using A Modified Image Formation Model (변형된 영상 생성 모델을 이용한 칼라 영상 보정)

  • Choi, Ho-Hyoung;Yun, Byoung-Ju
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.48 no.1
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    • pp.71-79
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    • 2011
  • The objective of the imaging pipeline is to transform the original scene into a display image that appear similar, Generally, gamma adjustment or histogram-based method is modified to improve the contrast and detail. However, this is insufficient as the intensity and the chromaticity of illumination vary with geometric position. Thus, MSR (Multi-Scale Retinex) has been proposed. the MSR is based on a channel-independent logarithm, and it is dependent on the scale of the Gaussian filter, which varies according to input image. Therefore, after correcting the color, image quality degradations, such as halo, graying-out, and dominated color, may occur. Accordingly, this paper presents a novel color correction method using a modified image formation model in which the image is divided into three components such as global illumination, local illumination, and reflectance. The global illumination is obtained through Gaussian filtering of the original image, and the local illumination is estimated by using JND-based adaptive filter. Thereafter, the reflectance is estimated by dividing the original image by the estimated global and the local illumination to remove the influence of the illumination effects. The output image is obtained based on sRGB color representation. The experiment results show that the proposed method yields better performance of color correction over the conventional methods.

Design and Implementation of Adaptive Beam-forming System for Wi-Fi Systems (무선랜 시스템을 위한 적응형 빔포밍 시스템의 설계 및 구현)

  • Oh, Joohyeon;Gwag, Gyounghun;Oh, Youngseok;Cho, Sungmin;Oh, Hyukjun
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.9
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    • pp.2109-2116
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    • 2014
  • This paper presents the implementation and design of the advanced WI-FI systems with beam-forming antenna that radiate their power to the direction of user equipment to improve the overall throughput, contrast to the general WI-FI systems equipped with omni-antenna. The system consists of patch array antenna, DSP, FPGA, and Qualcomm's commercial chip. The beam-forming system on the FPGA utilizes the packet information from Qualcomm's commercial chip to control the phase shifters and attenuators of the patch array antenna. The PCI express interface has been used to maximize the communication speed between DSP and FPGA. The directions of arrival of users are managed using the database, and each user is distinguished by the MAC address given from the packet information. When the system wants to transmit a packet to one user, it forms beams to the direction of arrival of the corresponding user stored in the database to maximize the throughput. Directions of arrival of users are estimated using the received preamble in the packet to make its SINR as high as possible. The proposed beam-forming system was implemented using an FPGA and Qualcommm's commercial chip together. The implemented system showed considerable throughput improvement over the existing general AP system with omni-directional antenna in the multi-user communication environment.

c-fos mRNA Expression in the Vestibular System following Hypergravity Stimulation in Rats

  • Jin Guang-Shi;Lee Jae-Hyo;Lee Jae-Hee;Lee Moon-Young;Kim Min-Sun;Jin Yuan Zhe;Song Jeong-Hoon;Park Byung-Rim
    • The Korean Journal of Physiology and Pharmacology
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    • v.11 no.1
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    • pp.1-7
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    • 2007
  • Altered environmental gravity, including both hypo- and hypergravity, may result in space adaptation syndrome. To explore the characteristics of this adaptive plasticity, the expression of immediate early gene c-fos mRNA in the vestibular related tissues following an exposure to hypergravity stimulus was determined in rats. The animals were subjected to a force of 2 g (twice earth's gravity) for 1, 3, or 12 h, and were examined poststimulus at 0, 2, 6, 12, and 24 h. RT-PCR (reverse transcription polymerase chain reaction) and real-time quantitative RT-PCR were adopted to analyze temporal changes in the expression of c-fos mRNA. The hypergravity stimulus increased the expression of c-fos mRNA in the vestibular ganglion, medial vestibular nucleus, inferior vestibular nucleus, hippocampus, cerebellum, and cortex. The peak expression occurred at 0 h poststimulation in animals stimulated with hypergravity for 1 h, and at 6 h poststimulus in those stimulated for 3 h. In contrast, those stimulated for 12 h exhibited dual peaks at 0 and 12 h poststimulus. Bilateral labyrinthectomy markedly attenuated the degree of c-fos mRNA expression. Glutamate receptor antagonist also dramatically attenuated the degree of c-fos mRNA expression. These results indicate that expression of c-fos mRNA in response to hypergravity occurs in the vestibular related tissues of the central nervous system, in which peripheral vestibular receptors and glutamate receptors play an important role. The temporal pattern of c-fos mRNA expression depended on the duration of the hypergravity stimulus.

A Survey on the Parents' Perceptions of and Attitudes toward Game Use among Teenagers in Korea (청소년 게임이용에 대한 학부모의 인식 조사 연구)

  • Hoon-Seok Choi;Joung Soon Ryong;Kyo-Heon Kim
    • Korean Journal of Culture and Social Issue
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    • v.17 no.4
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    • pp.435-459
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    • 2011
  • The present study explored Korean parents' perceptions of and behavior toward game use among teenagers in Korea. A total of 600 Korean mothers of teenagers residing in Seoul and five other metropolitan areas participated in the survey. The survey was constructed based on five categories of variables, including the overall perception of games and game use, specific attitudes toward game use, cognitions about and attitudes toward game addiction, factors predicting parental monitoring of children's game use, and views and opinions about what needs to be done to promote healthy game cultures as well as to prevent problematic game use among teenagers in Korea. Results indicate that the respondents' overall perceptions of and attitudes toward games and game use are negative. In contrast, attitudes toward game use of the respondent's own child are contingent upon various comparison standards. Results also indicate that the respondents tend to overestimate the possibility that their own child is addicted to games, and their perceptions of game addiction are based on a narrow range of behavioral symptoms. Additional analyses indicate that parental monitoring of teenagers' game use can be predicted by the theoretical model driven from Ajzen(1991)'s theory of planned behavior. Finally, results also indicate that, in order to deal with the problems associated with teenagers' game use, proactive approaches to promote healthy game cultures as well as various initiatives to prevent problematic game use are necessary. Implications of the findings and future direction were discussed.

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