• Title/Summary/Keyword: gradient reduction

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Crosstalk Reduction of Glasses-free 3D Displays using Multiview Image Processing (다시점 영상처리를 이용한 무안경 3차원 디스플레이의 크로스톡 저감 방법)

  • Kim, Sung-Yeol;Lee, Jin-Sung;Choi, Sang Mi
    • Journal of Broadcast Engineering
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    • v.21 no.1
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    • pp.66-75
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    • 2016
  • In this paper, we present a new method to reduce crosstalk of a glasses-free three-dimensional (3D) display using a multi-view image processing technique. Since crosstalk makes the current view image mixed with its neighboring ones, the output 3D image becomes severely blurred. We apply adaptive depth retargeting and view gradient-based crosstalk inverse filtering onto a multi-view image to minimize crosstalk of the glasses-free 3D display. In addition, overflow and underflow pixels are compensated by epipolar image pixel interpolation so that visual artifacts are minimized. Experimental results show that the proposed method reduces crosstalk more efficiently than the previous work while improving 3D image quality.

Microbial Enrichment and Community Analysis for Bioelectrochemical Acetate Production from Carbon Dioxide (이산화탄소로부터 생물전기화학적 아세트산 생산을 위한 미생물 농화배양 및 군집 분석)

  • Kim, Junhyung;Kim, Young-Eun;Park, Myeonghwa;Song, Young Eun;Seol, Eunhee;Kim, Jung Rae;Oh, You-Kwan
    • New & Renewable Energy
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    • v.16 no.1
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    • pp.58-67
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    • 2020
  • Microbial electrosynthesis has recently been considered a potentially sustainable biotechnology for converting carbon dioxide (CO2) into valuable biochemicals. In this study, bioelectrochemical acetate production from CO2 was studied in an H-type two-chambered reactor system with an anaerobic microbial consortium. Metal-rich mud flat was used as the inoculum and incubated electrochemically for 90 days under a cathode potential of -1.1 V (vs. Ag/AgCl). Four consecutive batch cultivations resulted in a high acetate concentration and productivity of 93 mmol/L and 7.35 mmol/L/day, respectively. The maximal coulombic efficiency (rate of recovered acetate from supplied electrons) was estimated to be 64%. Cyclic voltammetry showed a characteristic reduction peak at -0.2~-0.4 V, implying reductive acetate generation on the cathode electrode. Furthermore, several electroactive acetate-producing microorganisms were identified based on denaturing- gradient-gel-electrophoresis (DGGE) and 16S rRNA sequence analyses. These results suggest that the mud flat can be used effectively as a microbial source for bioelectrochemical CO2 conversion.

Quantitative Determination and Antioxidant Effects of Cheonwangbosimdan (LC-MS/MS를 이용한 천왕보심단(天王補心丹)의 함량분석 및 항산화 효능 연구)

  • Seo, Chang-Seob;Kim, Ohn Soon;Shin, Hyeun-Kyoo
    • Korean Journal of Pharmacognosy
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    • v.45 no.4
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    • pp.300-314
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    • 2014
  • An ultra-performance liquid chromatography-electrospray ionization-mass spectrometer (UPLC-ESI-MS) method was established for the simultaneous quantification of eighteen marker compounds in traditional Korean formula, Cheonwangbosimdan (CWBSD). In addition, we evaluated the antioxidant effects of CWBSD. Eighteen marker components were separated on a UPLC BEH $C_{18}$ analytical column ($2.1{\times}100mm$, $1.7{\mu}m$) and kept at $45^{\circ}C$ by gradient elution with 0.1% (v/v) formic acid in water and acetonitrile as mobile phase. The flow rate was 0.3 mL/min and the injection volume was $2.0{\mu}L$. The antioxidant activities of CWBSD were assessed by measuring free radical scavenging activities on 2,2'-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and 1-1-diphenyl-2-picrylhydrazyl (DPPH). The calibration curves of all analytes showed good linearity (correlation coefficient ${\geq}0.9937$) within the test ranges. The limits of detection and quantification for the 18 marker compounds were 0.01-4.71 ng/mL and 0.03-14.13 ng/mL, respectively. The contents of the 18 compounds in CWBSD extract ranged from none to $1701.00{\mu}g/g$. The CWBSD showed the radical scavenging activity in a dose-dependent manner. The concentration required for 50% reduction ($RC_{50}$) against ABTS and DPPH radicals were $149.42{\mu}g/mL$ and $339.24{\mu}g/mL$.

A Pedestrian Detection Method using Deep Neural Network (심층 신경망을 이용한 보행자 검출 방법)

  • Song, Su Ho;Hyeon, Hun Beom;Lee, Hyun
    • Journal of KIISE
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    • v.44 no.1
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    • pp.44-50
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    • 2017
  • Pedestrian detection, an important component of autonomous driving and driving assistant system, has been extensively studied for many years. In particular, image based pedestrian detection methods such as Hierarchical classifier or HOG and, deep models such as ConvNet are well studied. The evaluation score has increased by the various methods. However, pedestrian detection requires high sensitivity to errors, since small error can lead to life or death problems. Consequently, further reduction in pedestrian detection error rate of autonomous systems is required. We proposed a new method to detect pedestrians and reduce the error rate by using the Faster R-CNN with new developed pedestrian training data sets. Finally, we compared the proposed method with the previous models, in order to show the improvement of our method.

Effect of Nifedipine on the Ampicillin Absorption (니페디핀이 암피실린의 흡수에 미치는 영향)

  • Jeong, Hyun-Jeong;Yong, Chul-Soon;Choi, Yoon-Soo;Oh, Doo-Man
    • Journal of Pharmaceutical Investigation
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    • v.27 no.1
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    • pp.57-64
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    • 1997
  • $Amino-{\beta}-lactam$ antibiotics are absorbed by the dipeptide transporter in the small intestine. These uptakes are coupled to a proton influx. The inward proton gradient is partly induced by the $Na^+/H^+$ exchanger and calcium ion is involved in control of this antiport. Interaction between ampicillin which is one of the $Amino-{\beta}-lactam$ antibiotics and nifedipine which is one of calcium channel blocking agents was studied in rats in vivo and with rabbit jejunum mounted on the Sweetana/Grass diffusion cells in vitro. Bioavailability of ampicillin was increased significantly when nifedipine was co-administered orally in rats. There were no differences in the distribution phase and the elimination phase when ampicillin was given either alone or with nifedipine intravenously. Conditions for in vitro experiments were determined. The lift rate of $O_2/CO_2$ gas was controlled to 3 bubbles/sec and ampicillin was stable in the Kreb's buffer at pH 6.0. Absorption of ampicillin was the greatest when the completely-stripped serosal membrane was used. Transport of ampicillin from mucosal to serosal side in the rabbit jejunum was enhanced by 32% in the presence of nifedipine (p=0.059). Above results suggest that nifedipine might increase the plasma level of ampicillin via the improved absorption in the intestine rather than the reduction in the elimination or/and alteration in the distribution.

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An Experimental Study on the Control of the Combustion Rate by Temperature Control of Gas Entrained into the Filter in Burner-Type Particulate Trap (버너방식 DPF 시스템에서 가스온도 제어를 통한 입자상물질 연소율제어의 실험적 검증)

  • Park, D. S.;Kim, J. U.;Cho, H.;Kim, E. S.
    • Transactions of the Korean Society of Automotive Engineers
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    • v.5 no.4
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    • pp.130-141
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    • 1997
  • Work on the reduction of particulate matter(PM) from a diesel vehicl has led to a new trp system and a control method to control the combustion rate of the PM filtrated in the trap, which was named as 'Active Exhaust Feeding Regeneration(AEFR) System' by its operation mechanism. Ceramic cordierite filter is a major component of the trap and susceptible to thermal shock. Therefore the system should be designed to reduce the peak temperature and temperature gradients in the trap ; these have been considered to be the main factors causing thermal shock of the filter during the regeneration. It uses the engine's exhaust gas partially for the regeneration of the ceramic filter. It controlled bypass flow rate of the engine's exhaust gas precisely to control the temperature of the gas entrained into the filter. Gas temperatures were measured inside filter, and the oxygen concentration at the outlet of the filter was also monitored during the regeneration to analyze the combustion process of the PM. The temperature distributions and temperature gradients in the filter during the regeneration varied widely according to the regeneration control schemes. Finally, this system shows relatively low peak temperature and temperature gradients in the filter during its regeneration. It is considered that this system uses a mew method to control the combustion rate of the PM, which is different from the methods used in the previous studies.

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Characteristic Analysis on Temporal Variation of Green-tourism Potential in Rural Villages (농촌마을 관광잠재력의 시간적 변화 특성 분석)

  • Kim, Dae-Sik;Choi, Hyun-Sung
    • Journal of The Korean Society of Agricultural Engineers
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    • v.49 no.6
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    • pp.77-84
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    • 2007
  • This study aims to analyze temporal variation of rural tourist potential in village level. In order to analyze the temporal variation, this study applied a green-tourism potential evaluation model(GPEM) to a study area, Namilmyun with 18 villages, which located on county of Kumsan, province of Chungnam. GPEM consists of two factors about human resources, which is quantified by resident population of the village who will be participated in village management for green-tourism, and amenity resources, which is calculated by an evaluation table with 31 criteria and their weighting values. Data surveying for the study area was performed at August 2003 and 2006, respectively, in order to quantity the 31 evaluation criteria of GPEM. From the analysis results, the amenity resources with three sub-classes of industrial, natural, and social resources showed that the evaluation values of 2006 were increased in more than those of 2003, displaying the increase rate of ranging from 108% to 112% in the three sub-classes, except of one village in social resources and three village in natural resources with reduction. In human resources, the evaluation values of 2006 were highly increased more than those of 2003, showing the rate of 556% in the gradient of linear regression line. In green tourism potential in each village, the evaluation results for two time series showed that the potential is increased by time, which the increase rate of the potential is 114%. Ultimately, the results of this study enable us to realize that the green-tourism potential in each village over time is increased, for example, due to developing new facilities in the village by investment of government and participating in rural tourism by resident people over time. From the analysis and results, the methodology of this study can be applied to analyze the temporal variation of the potential for villages having investment from government.

Spatiotemporal Variations and Possible Sources of Ambient PM10 from 2003 to 2012 in Luzhou, China

  • Ren, Dong;Li, Youping;Zhou, Hong;Yang, Xiaoxia;Li, Xiaoman;Pan, Xuejun;Huang, Bin
    • Environmental Engineering Research
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    • v.19 no.4
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    • pp.331-338
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    • 2014
  • Descriptive statistics methods were used to study the spatiotemporal variations and sources of ambient particulate matter ($PM_{10}$) in Luzhou, China. The analyzed datasets were collected from four national air quality monitoring stations: Jiushi (S1), Xiaoshi (S2), Zhongshan (S3), Lantian (S4) over the period of 2003-2012. This city was subjected serious $PM_{10}$ pollution, and the long-term annual average $PM_{10}$ concentrations varied from 76 to $136{\mu}g/m^3$. The maximum concentration was more than 3-fold of the annual average ($40{\mu}g/m^3$) issued by EPA-China for the ambient air quality. General temporal pattern was characterized by high concentrations in winter and low concentrations in summer, and general spatial gradient was in the reduction order of S2 > S4 > S3 > S1, which were both due to different particulate contributors and special meteorological conditions. The source apportionment indicated that vehicular emissions, road dusts, coal burning and chemical dusts were the major contributors of the identified $PM_{10}$ pollution, and the vehicular emissions and the road wear re-suspended particles dominated the heavy $PM_{10}$ pollution in recent years. Two other potential sources, agricultural and celebration activities could decrease the air quality in a short term. Finally, some corresponding suggestions and measures were provided to improve the air quality.

An Efficient Vehicle Image Compensation Algorithm based on Histogram Equalization (히스토그램 균등화 기반의 효율적인 차량용 영상 보정 알고리즘)

  • Hong, Sung-Il;Lin, Chi-Ho
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.3
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    • pp.2192-2200
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    • 2015
  • In this paper, we propose an efficient vehicle image compensation algorithm based on Histogram Equalization. The proposed a vehicle image compensation algorithm was elimination to the vehicle image shake using motion compensation and motion estimation. And, algorithm was calculated the histogram of pixel values from each sub-image by dividing the image as the constant size areas in order to image enhancement. Also, it had enhancement to the image by adjusting the gradient. The proposed algorithm was evaluate the difference between of performance and time, image by applied to the IP, and were confirmed the image enhancement with removing of vehicle camera image shake. In this paper, the proposed vehicle image enhancement algorithm was demonstrated effectiveness when compared to existing vehicle image stabilization, because the elimination of shake for the vehicle images used real-time processing without using a memory. And it was obtained the reduction effect of the computation time by the calculated through block matching, and obtained the better restoration result for naturalness of the image with the lowest noise.

Exosomes from Murine-derived GL26 Cells Promote Glioblastoma Tumor Growth by Reducing Number and Function of CD8+T Cells

  • Liu, Zhi-Ming;Wang, Yu-Bin;Yuan, Xian-Hou
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.1
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    • pp.309-314
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    • 2013
  • Aim: Brain tumors almost universally have fatal outcomes; new therapeutics are desperately needed and will only come from improved understandins of glioma biology. Methods: Exosomes are endosomally derived 30~100 nm membranous vesicles released from many cell types. Examples from GL26 cells were here purified using density gradient ultracentrifugation and monitored for effects on GL26 tumor growth in C57BL/6j mice (H-2b). Lactate dehydrogenase release assays were used to detect the cytotoxic activity of CD8+T and NK cells. Percentages of immune cells producing intracellular cytokines were analyzed by FACS. Results: In this study, exosomes from murine-derived GL26 cells significantly promoted in vivo tumor growth in GL26-bearing B6 mice. Then we further analyzed the effects of the GL26 cells-derived exosomes on immune cells including CD8+T, CD4+T and NK cells. Inhibition of CD8+T cell cytotoxic activity was demonstrated by CD8+T cell depletion assays in vivo and LDH release assays in vitro. The treatment of mice with exosomes also led to a reduction in the percentages of CD8+T cells in splenocytes as determined by FACS analysis. Key features of CD8+T cell activity were inhibited, including release of IFN-gamma and granzyme B. There were no effects of exosomes on CD4+T cells and NK cells. Conclusion: Based on our data, for the first time we demonstrated that exosomes from murine derived GL26 cells promote the tumor growth by inhibition of CD8+T cells in vivo and thus may be a potential therapeutic target.