• 제목/요약/키워드: MsrA

검색결과 139건 처리시간 0.023초

HSV 컬러 공간에서의 레티넥스와 채도 보정을 이용한 화질 개선 기법 (Image Quality Enhancement Method using Retinex in HSV Color Space and Saturation Correction)

  • 강한솔;고윤호
    • 한국멀티미디어학회논문지
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    • 제20권9호
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    • pp.1481-1490
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    • 2017
  • This paper presents an image quality enhancement algorithm for dark image acquired under poor lighting condition. Various retinex algorithms which are human perception-based image processing methods were proposed to solve this problem. Although MSR(Multi-Scale Retinex) among these algorithm works well under most lighting condition, it shows color degradation because their separate nonlinear processing of RGB color channels. To compensate for the loss of the color, MSRCR(Multi-Scale Retinex with Color Restoration) was proposed. However, it requires high computational load and has additional parameters that need to be adjusted according to input image. In order to overcome this problem, a new retinex algorithm based on MSR is proposed in this paper. The proposed method consists of V channel MSR, saturation correction, and separate contrast enhancement process. Experimental results show that the subjective and objective image quality of the proposed method better than those of the conventional methods.

저성능 자기차폐실에서 64채널 DROS 2차 미분계 시스템의 잡음 특성 (Noise Characteristics of 64-channel 2nd-order DROS Gradiometer System inside a Poorly Magnetically-shielded Room)

  • 김진목;이용호;유권규;김기웅;권혁찬;박용기
    • Progress in Superconductivity
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    • 제8권1호
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    • pp.33-39
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    • 2006
  • We have developed a second-order double relaxation oscillation SQUID(DROS) gradiometer with a baseline of 35 mm, and constructed a poorly magnetically-shielded room(MSR) with an aluminum layer and permalloy layers for magnetocardiography(MCG). The 2nd-order DROS gradiometer has a noise level of 20 $fT/{\surd}Hz$ at 1 Hz and 8 $fT/{\surd}Hz$ at 200 Hz inside the heavily-shielded MSR with a shielding factor of $10^3$ at 1 Hz and $10^4-10^5$ at 100 Hz. The poorly-shielded MSR, built of a 12-mm-thick aluminum layer and 4-6 permalloy layers of 0.35 mm thickness, is 2.4mx2.4mx2.4m in size, and has a shielding factor of 40 at 1 Hz, $10^4$ at 100 Hz. Our 64-channel second-order gradiometer MCG system consists of 64 2nd-order DROS gradiometers, flux-locked loop electronics, and analog signal processors. With the 2nd-order DROS gradiometers and flux-locked loop electronics installed inside the poorly-shielded MSR, and with the analog signal processor installed outside it, the noise level was measured to be 20 $fT/{\surd}Hz$ at 1 Hz and 8 $fT/{\surd}Hz$ at 200 Hz on the average even though the MSR door is open. This result leads to a low noise level, low enough to obtain a human MCG at the same level as that measured in the heavily-shielded MSR. However, filters or active shielding is needed fur clear MCG when there is large low-frequency noise from heavy air conditioning or large ac power consumption near the poorly-shielded MSR.

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MSR (Mechanically induced Self-sustaining Reaction)이 억제된 반응성 밀링에 의해 제조된 분산강화 페라이트의 미세조직과 기계적 특성 (Microstructure and Mechanical Properties of ODS Ferrite Produced by Reactive Milling for the MSR Suppression)

  • 황승준
    • 열처리공학회지
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    • 제26권6호
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    • pp.279-287
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    • 2013
  • Oxide Dispersion Strengthened (ODS) Fe with $Al_2O_3$ dispersoid was successfully produced by reactive milling with a mixture of Fe, $Fe_3O_4$ (Magnetite), $Fe_2O_3$ (Hematite) and Al reactants at cryogenic temperature. The milled powders were consolidated by Vacuum Hot Press (HP) at 1323 K, and the consolidated materials were characterized by Transmission Electron Microscopy (TEM), Scanning Transmission Electron Microscopy (STEM), and Energy Dispersive Spectroscopy (EDS); the yield strength and the hardness of the consolidated materials were determined by compressive test and Vickers hardness test at room temperature. The grain size of the materials was estimated by X-ray Diffraction technique using the scherrer's formula. The TEM observations showed that the microstructure was comprised with a mixture of nanocrystalline Fe matrix and $Al_2O_3$ nano-dispersoids with a bimodal size distribution; the 0.2% off-set yield strength of the materials was as high as $758{\pm}29$ MPa and the Vickers hardness was $358{\pm}2$. The effect of the cryogenic milling and addition of extra Fe powder was discussed on the suppression of MSR (Mechanically induced Self-sustaining Reaction) for the desired microstructural evolution of ODS alloys.

Initiation, proliferation, and improvement of a micropropagation system for mass clonal production of banana through shoot-tip culture

  • Khaskheli, Allah Jurio;Ali, Muharam;Shah, Syad Zakir Hussain;Memon, Zohra Fatima;Awan, Saleem;Khaskheli, Muhammad Ibrahim;Khaskheli, Mohsin Ali;Magsi, Bilqees;Qambrani, Zareen;Khaskheli, Asad Ali
    • Journal of Plant Biotechnology
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    • 제48권2호
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    • pp.86-92
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    • 2021
  • The present study aimed to evaluate the initiation, proliferation potential, and mass clonal production ability of a micropropagation system for banana through tissue culture. A total of 60 explants were cultured on basal media supplemented with various concentrations of BAP and NAA. Banana plants regenerated on MS basal medium (control) without the addition of BAP + NAA showed a significantly (P < 0.05) lower survival rate with no signs of shoots up to the end of the experimental period. The results further revealed that the performance in MSS-XI medium was almost 89%, followed by MSS-IX and MSS-X media, both of which showed performance up to 88%. In contrast, the performance in the MSS-XVI medium was less than 60%, at the less duration of time and highly shoot induction detected at MSS-XIII medium. The maximum number of shoots (4.9) was observed in the medium supplemented with growth adjuster MSS-XI, followed by the MSS-XII medium (4.5). Surprisingly, the best performance was observed for the MSR-VII medium approximately 16 days after initiation, while the lowest performance was observed with MSR-XI (approximately 31 days). The maximum rooting percentage (98%) was observed in the MSR-V to MSR-VIII media (98%), while the minimum rooting percentage was observed in MSR-XI (approximately 45%).

Performance of Cu-SiO2 Aerogel Catalyst in Methanol Steam Reforming: Modeling of hydrogen production using Response Surface Methodology and Artificial Neuron Networks

  • Taher Yousefi Amiri;Mahdi Maleki-Kakelar;Abbas Aghaeinejad-Meybodi
    • Korean Chemical Engineering Research
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    • 제61권2호
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    • pp.328-339
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    • 2023
  • Methanol steam reforming (MSR) is a promising method for hydrogen supplying as a critical step in hydrogen fuel cell commercialization in mobile applications. Modelling and understanding of the reactor behavior is an attractive research field to develop an efficient reformer. Three-layer feed-forward artificial neural network (ANN) and Box-Behnken design (BBD) were used to modelling of MSR process using the Cu-SiO2 aerogel catalyst. Furthermore, impacts of the basic operational variables and their mutual interactions were studied. The results showed that the most affecting parameters were the reaction temperature (56%) and its quadratic term (20.5%). In addition, it was also found that the interaction between temperature and Steam/Methanol ratio is important on the MSR performance. These models precisely predict MSR performance and have great agreement with experimental results. However, on the basis of statistical criteria the ANN technique showed the greater modelling ability as compared with statistical BBD approach.

Sensitivity study of parameters important to Molten Salt Reactor Safety

  • Sarah Elizabeth Creasman;Visura Pathirana;Ondrej Chvala
    • Nuclear Engineering and Technology
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    • 제55권5호
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    • pp.1687-1707
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    • 2023
  • This paper presents a molten salt reactor (MSR) design parameter sensitivity study using a nodal dynamic modelling methodology with explicitly modified point kinetics equation and Mann's model for heat transfer. Six parameters that can impact MSR safety are evaluated. A MATLAB-Simulink model inspired by Thorcon's 550MWth MSR is used for parameter evaluations. A safety envelope was formed to encapsulate power, maximum and minimum temperature, and temperature-induced reactivity feedback. The parameters are perturbed by ±30%. The parameters were then ranked by their subsequent impact on the considered safety envelope, which ranks acceptable parameter uncertainty. The model is openly available on GitHub.

난지형 잔디의 가뭄 스트레스 상태로 인한 멀티스팩트럴 반사광 연구 (Multi-Spectral Reflectance of Warm-Season Turfgrasses as Influenced by Deficit Irrigation)

  • 이준희
    • 아시안잔디학회지
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    • 제22권1호
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    • pp.1-12
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    • 2008
  • Multi-spectral radiometer (MSR)를 사용한 리모트 센싱 기술이 향 후 잔디의 건조스트레스를 감지할 수 있는 도구로 사용될 수 있다. 본 연구의 목적은 네가지 각기 다른 조건의 건조스트레스를 받은 난지형 잔디의 잎에서 반사되는 Reflectance와 토양수분, 비주얼 잔디상태, 엽록소 함량, 광합성 등을 측정하여 각 factor간의 상관관계를 조사했으며 본 연구를 통해 모든 factor가 MSR 데이터와 질은 상관관계를 가지고 있었다. 또한 Reflectance 민감도는Visual spectral region보다 Infrared spectral region에서 더 높음을 알 수 있었다. 모든 결과를 종합해 볼 때 Multi-spectral radiometer (MSR)은 잔디의 건조상태를 미리 예측할 수 있는 도구로 사용될 수 있음을 확인할 수 있었다. 이 기술의 자료를 활용하게 된다면 향 후 MSR이 부착된 기구(Balloon)를 이용한 필드 스터디 연구로 확대될 수 있을 것이다.

중국 일대일로 항만의 효율성 평가 (Evaluating the Efficiency of Chinese Ports from the Perspective of Maritime Silk Road)

  • 왕관;안승범
    • 한국항만경제학회지
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    • 제37권1호
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    • pp.19-30
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    • 2021
  • 21 세기 해양 실크로드 (MSR)는 일대일로 이니셔티브 (BRI)의 핵심적인 부분이다. 아시아, 유럽, 아프리카 등 수십 개 국가의 경제 및 무역 통로이자 중요한 연결 노드인 항만과 항만 운영의 효율성은 BRI의 전략 실행에 직접적인 영향을 미친다. 본 논문에서는 BRI 및 관련 항만 효율 평가 방법을 결합한 DEA-BCC 모델을 사용하여 항만 생산 선석 수와 생산 선석 길이를 입력 지표 컨테이너 처리량으로, 화물 처리량을 출력 지표로 선택하여 14 개 항만의 항만 효율성을 분석하였다. 결과는 다음으로 요약된다 : (1) MSR을 따라 항만의 전반적인 효율성 수준이 낮게 나타난다. 대부분의 항만은 DEA 효율성에 도달하지 못하였고 투자규모 및 기술 개선에 있어 상이한 문제를 보여준다. 하지만 이러한 상황은 중국의 해양 협력 전략의 실행과 함께 해마다 개선되고 있다. (2) MSR 항만의 낮은 운영 효율성은 주로 규모 효율성과 기술 효율성 간의 조정 부족 때문으로 볼 수 있다. 이는 항만 자체에 대한 투자규모가 불충분하고 배후지와 항만 간의 유기적인 연계가 취약하기 때문이다. (3) 항만이 종합적인 경쟁력 확보 여부는 화물 처리량이나 규모에 전적으로 의존하지 않고 항만 운영 효율성도 포함되어 역할을 하는 것으로 파악된다

전력계통의 전압안정도향상을 위한 감시제어시스템 개발 (A Development of Monitoring and Control System for Improved the Voltage Stability in the Power System)

  • 이현철;정기석;박지호;백영식
    • 전기학회논문지
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    • 제62권4호
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    • pp.437-443
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    • 2013
  • This paper was developed a monitoring and control system to use reactive power control algorithm. This algorithm could be improved voltage stability in power system. This method was controlled the voltage for stability improvement, effective usage of reactive power, and the increase of the power quality. PMS(Power Management System) has been calculate voltage sensitivity, and control reactive power compensation device. The voltage control was used to the FACTS, MSC/MSR(Mechanically Switched Capacitors/Reactors), and tap of transformer in power system. The reactive power devices in power system were control by voltage sensitivity ranking of each bus. Also, to secure momentary reactive power, it had been controlled as the rest of reactive power in the each bus. In here, reactive power has been MSC/MSR. The simulation result, First control was voltage control as fast response control of FACTS. Second control was voltage control through the necessary reactive power calculation as slow response control of MSR/MSR. Third control was secured momentary reactive reserve power. This control was method by cooperative control between FACTS and MSR/MSC. Therefore, the proposed algorithm was had been secured the suitable reactive reserve power in power system.

갑천 유역을 대상으로 토지이용예측모델 비교 분석 (Comparative Analysis of Land Use Change Model at Gapcheon Watershed)

  • 권필주;류지철;이동준;한정호;성윤수;임경재;김기성
    • 한국물환경학회지
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    • 제32권6호
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    • pp.552-561
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    • 2016
  • For the prediction of hydrologic phenomenon, predicting future land use change is a very important task. This study aimed to compare and analyze the two land use change models, CLUE-S and SLEUTH3-R. The analysis of two models were performed based on the MSR value such that the model with more reliable MSR value can be recommended as an appropriate land use change prediction model. The model performance was examined by applying to the Gapcheon A watershed. Land use map of the study area of 2007 obtained from the Ministry of Environment was compared with the predicted land use map obtained from each of the two models. The result from both models showed somewhat similar results. The MSR value obtained from CLUE-S was 0.564, while that from SLEUTH3-R was 0.586. However, when land use map of 2010 was compared with predicted land use map obtained from the two models in same manner, the MSR value obtained from CLUE-S' was 0.500 while that from SLEUTH3-R was decreased to 0.397, an approximately 32.3% decrease from previous value of 2007. Moreover, SLEUTH3-R showed more sensitivity in conversion of urban areas, as compared to other land use types. Therefore, for the prediction of future land use change, CLUE-S model is more reliable than SLEUTH3-R.