• Title/Summary/Keyword: Miller method

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Study on the Performance Factors of Two Stage Turbo-Charging System and Maximization of the Miller Cycle (2단 과급시스템의 성능 인자 영향과 밀러 효과 극대화에 관한 연구)

  • Beak, Hyun-min;Seo, Jung-hoon;Lee, Won-ju;Lee, Ji-woong
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.25 no.7
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    • pp.953-960
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    • 2019
  • The Miller cycle is a diesel engine that has been developed in recent years that it can reduce NOx and improve fuel consumption by reducing the compression ratio through intake valve closing (IVC) time control. The Miller cycle can be divided into the early Miller method of closing the intake valve before the bottom dead center (BDC) and the late Miller method of closing the intake valve after the BDC. At low speeds, the late Miller method is advantageous as it can increase the volumetric efficiency; while at medium and high speeds, the early Miller method is advantageous because of the high internal temperature reduction effect due to the expansion of the intake air during the piston lowering from IVC to BDC. Therefore, in consideration of the ef ects of the early and late Miller methods, it is necessary to adopt the most suitable Miller method for the operating conditions. In this study, a two-stage turbo charge system was applied to four-stroke engines and the process of enhancing the Miller effect through a reduction of the intake and exhaust valve overlap as well as the valve change adjustment mechanism were considered. As a result, the ef ects of fuel consumption and Tmax reduction were confirmed by adopting the Miller cycle with a two-stage supercharge, a reduction of valve overlap, and an increase of suction valve lift.

Volatile Components of Lycium chinensis Miller (구기자(Lycium chinensis Miller)의 휘발성 성분)

  • 박원종;복진영;백순옥;한상빈;주현균
    • The Korean Journal of Food And Nutrition
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    • v.10 no.1
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    • pp.1-5
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    • 1997
  • The volatile components of Lycium chinensis Miller were isolated by simultaneous steam distillation-extraction(SDE) method and analyzed by combined GC and GC-MS. Fifty-four volatile components, including 12 alcolhols 12 esters, 7 aldehydes, 6 acids, 5 ydrocarbons, 8 ketones, 1 furan and 3 pyrazines were confirmed in the fruit of Lycium chinensis Miller. The major components were hexadecanoic acid ethyl ester, 1-octadecanone, tetrapyrazine, 2-furancarboxaldehyde and ethyl linoleate.

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Creep Life Prediction for Udimet 720 Material Using the Initial Strain Method (ISM)

  • Kong, Yu-Sik;Yoon, Han-Ki;Oh, Sae-Kyoo
    • Journal of Mechanical Science and Technology
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    • v.17 no.4
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    • pp.469-476
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    • 2003
  • Despite of considerable research results or uniaxial tension creep available for superalloys, few studies have been made on high temperature creep using the Initial Stram Method (ISM) In this paper, the real-time prediction of high temperature creep strength and creep lift for the nickel-based superalloy Udimet 720 (high-temperature and high-pressure gas turbine engine materials) was performed on round-bar type specimens under pure static load at the temperatures of 538$^{\circ}C$. 649$^{\circ}C$, and 704$^{\circ}C$. The predictive equation derived from the ISM in creep tests showed better reliability than those from LMP (Larson-Miller Parameter) and LMP-lSM (Larson Miller Parameter-Initial Strain Method) specially for long time creep prediction (10$^3$∼10$\^$5/h).

The Washing Characteristics of Lycium chinense Miller with Different Washing Methods (구기자 세척기 개발을 위한 구기자의 세척특성)

  • Lee, Seung-Ki;Han, Jae-Woong;Jeon, Myung-Jin;Park, Won-Jong;Baek, Seung-Woo;Kim, Wong
    • Journal of Biosystems Engineering
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    • v.35 no.4
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    • pp.244-249
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    • 2010
  • This study was conducted to define the optimal Lycium chinense miller washing method for developing the Lycium chinense cleaner and we analyzed the Lycium chinense miller washing characteristics for removing pesticides and microorganism according to washing methods; habitual washing method, air bubble washing method and nozzle spray washing method. The results were summarized as follows; 1. In case of measuring physical properties according to the varieties, maximum yield strength of Hokwang was 2.562 kgf, minimum yield strength of Hokwang was 0.269 kgf and average yield strength was about 1 kgf. 2. In case of measuring change of bacteria according to washing methods, the number of bacteria of non-washing method was more than the number of bacteria of habitual washing method or mechanical washing method and the number of nozzle spray washing method was least. 3. Ahjoksiseuteurobin of 0.218 ppm was detected in the untreated sample, 0.051 ppm was detected in the habitual washing method, 0.047 ppm was detected in the air bubble washing method and 0.034 ppm was detected in nozzle spray washing method. Every amount detected were less than 2 ppm that is reference value and the detected amount was least in case of nozzle spay cleaning method. Cypermethrin of 0.772 ppm was detected in the non-cleaned sample, 0.089ppm was detected in habitual washing method, 0.26 ppm was detected in the air bubble washing method and 0.292 ppm was detected in the nozzle spray washing method. Every detected amount of Cypermethrin were less than 5 ppm that is reference value and the detected amount was least in case of habitual washing method.

Antioxidative Activities and Contents of Polyphenolic Compound of Medicinal Herb Extracts (한약재 추출물의 폴리페놀 화합물과 항산화 활성)

  • 박영숙
    • Journal of the East Asian Society of Dietary Life
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    • v.12 no.1
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    • pp.23-31
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    • 2002
  • The antioxidative activity was measured on the substances of water and ethanol soluble extract from Astragalus membranaceus Bunge, Chrysanthemum morifolium Ramat, Lycium chinensis Miller, Glycyrrhiza uralensis Fischer, Angelica gigas Nakai, Zizyphus jojoba Miller, Paeonia lactiflora Pallas, Cnidium officinale Makino by four different in vitro experimental models of DPPH (a,a'-diphenyl-$\beta$-picrylhydrazyl) method, superoxide dismutase like activity, thiocyanate method, and TBARS (thiobarbituric acid reactive substances) method. The Lycium chinensis Miller contained the highest amount of polyphenolic compounds. The electron donating ability of water extract from Glycyrrhiza uralensis Fischer and ethanol extract from Chrysanthemum were higher than those of the others. The superoxide dismutase-like activity of water extract from Astragalus membranaceus Bunge was the highest among those of all the others. The water extract from Zizyphus jujuba Miller showed the highest antioxidative activity determined by TBARS method. Compared to the control, the inducing period associated with the oxidation degree was delayed up to 8 days in both the water extract from Chrysanthemum, Lycium chinensis Miller, Glycyrrhiza uralensis Fischer, and Paeonia lactiflora Pallas and the in ethanol extract from Chrysanthemum and Glycyrrhiz uralensis Fischer. These results support that water and ethanol extracts from 8 kinds of medicinal herbs contain antioxidative compounds.

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A Study on the Remanufacturing for Drive Spur Gear in Planner Miller by Directed Energy Deposition

  • Jin, Chul-Kyu;Kim, Min-Woo;Woo, Jae-Hyeog
    • Journal of the Korean Society of Industry Convergence
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    • v.25 no.6_1
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    • pp.941-952
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    • 2022
  • In this study, additive manufacturing technology was applied to restore a planner miller that was unusable due to aging. The drive spur gear of the planner miller was inoperable due to many defects in the teeth. The shape of the defective gear teeth was restored by deposition of the defective teeth using the DED method. However, as the location of the deposition head and the location of the set origin became farther, the deposition shape was different from the modeling shape. Nonetheless, since the modeling of the deposition part was designed to be larger than the tooth shape of the original gear, it was possible to completely restore all gear teeth through post-processing. The arrangement interval of the flow lines of the deposition part was narrower than that of the substrate. The hardness of the substrate was 172 HV, and that of the deposition part was 345 HV, which was twice as high as that of the substrate.

The Primality Test (소수 판별법)

  • Lee, Sang-Un;Choi, Myeong-Bok
    • Journal of the Korea Society of Computer and Information
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    • v.16 no.8
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    • pp.103-108
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    • 2011
  • Generally, Miller-Rabin method has been the most popular primality test. This method arbitrary selects m at k-times from m=[2, n-1] range and (m,n)=1. Miller-Rabin method performs $k{\times}r$ times and reports prime as $m^d\;{\equiv}\;1(mod\;n)$ or $m^{2^rd}\;{\equiv}\;-1(mod n)$ such that n-1=$2^sd$, $0\;{\leq}\;r\;{\leq}\;s-1$. This paper suggests more simple primality test than Miller-Rabin method. This test method computes c=$p^{\frac{n-1}{2}}(mod\;n)$ for k times and reports prime as c=-1. The proposed primality test method reduces $k{\times}r$ times of Miller-Rabin method to k times.

Frequency Response Analysis of Common-Source Amplifier Using the Exact Modeling of Miller Effect (밀러 효과의 정확한 모델링을 이용한 공통 소스 증폭기의 주파수 특성 연구)

  • Yi, Soonjai;Lee, Dong-Keon;Jeong, Hang-Geun
    • Journal of the Institute of Electronics and Information Engineers
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    • v.51 no.1
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    • pp.172-178
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    • 2014
  • This paper presents a new model of the Miller effect. The new Miller effect model is obtained from the accurate AC gain which includes the effect of the output capacitance of the common-source (CS) amplifier. The new Miller effect model consists of the series connection of a capacitance and a parallel RC circuit, one at the input and the other at the output. The frequency response obtained by the new Miller effect model is equal to that obtained from the original circuit. Even though the new model is complicated, the 3-dB frequency can be easily estimated by using the open-circuit time constants method without the node analysis.

Study on Reducing Processing Time for Restoration Method (영상신호 복원의 처리 시간단축을 위한 알고리즘에 대한 연구)

  • 권기홍
    • Journal of the Korea Computer Industry Society
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    • v.2 no.6
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    • pp.817-826
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    • 2001
  • In this paper, the method of processing a blurred noisy signal has been researched. The conventional method of processing signal has faults which are slow-convergence speed and long time-consuming process at the singular point and in the ill condition. There is the process, the Gauss-Seidel's method to remove these faults, but it takes too much time because it processes signal repeatedly. For overcoming the faults, this paper shows a signal process method which takes shorter than the Tikhnov-Miller's by comparing the Tikhnov-Miller's with proposed algorithm and accelerating convergence speed at the singular point in the ill condition. In this paper, the conventional process method and proposed optimal algorithm were used to get a standard image (256 * 256 * 8bits),and then the results are simulated and compared each other in order to examine the variance of MSE ( Mean-Square Error ) by the acceleration parameter in the proposed two dimensional signal procedures. The result of the signal process and the processing time was measured at all change of acceleration parameter in order to verify the effectiveness of the proposed algorithm.

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A Robust Pattern Watermarking Method by Invisibility and Similarity Improvement (비가시성과 유사도 증가를 통한 강인한 패턴 워터마킹 방법)

  • 이경훈;김용훈;이태홍
    • Journal of KIISE:Software and Applications
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    • v.30 no.10
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    • pp.938-943
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    • 2003
  • In this paper, we Propose a method using the Tikhonov-Miller process to improve the robustness of watermarking under various attacks. A visually recognizable pattern watermark is embedded in the LH2, HL2 and HH2 subband of wavelet transformed domain using threshold and besides watermark is embeded by utilizing HVS(Human Visual System) feature. The pattern watermark was interlaced after random Permutation for a security and an extraction rate. To demonstrate the improvement of robustness and similarity of the proposed method, we applied some basic algorithm of image processing such as scaling, filtering, cropping, histogram equalizing and lossy compression(JPEG, gif). As a result of experiment, the proposed method was able to embed robust watermark invisibility and extract with an excellent normalized correlation of watermark under various attacks.