• 제목/요약/키워드: (r,s)-components

검색결과 930건 처리시간 0.024초

비균일 대기상태를 고려한 함정의 적외선 신호 특성 분석 (ANALYSIS OF IRSIGNAL CHARACTERISTICS OF A SHIP FOR NON-UNIFORM ATMOSPHERIC CONDITIONS)

  • 최준혁;김도휘;한국일;하남구;장현성;이승하;김동건;김태국
    • 한국전산유체공학회지
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    • 제22권1호
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    • pp.88-94
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    • 2017
  • The IR signal entering into a sensor is composed of the following components: the self-emitted component directly from the object surface, the reflected components of the solar and sky irradiance at the object surface, and the scattered component by the atmosphere without reference to any object surfaces. The self-emitted and reflected components from the object can be lowered by the atmospheric layer between the object and the IR sensor. The principle factors influencing the atmospheric transmittance are the air temperature, the relative humidity and the observation distance. Previous studies on IR signal transmission through the atmosphere are focused on uniform atmospheric conditions and the non-uniform nature of the atmosphere was not properly treated in modeling. In this study, we use the local atmospheric transmittance to simulate the non-uniform atmosphere in analyzing the IR signal from the object surface. The results show that the nonuniform analysis of the atmosphere becomes more important as the wavelength of IR signal increases.

Reliability Equivalence of a Non-identical Components Parallel System

  • Montaser, M.;Sarhan, Ammar M.
    • International Journal of Reliability and Applications
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    • 제9권1호
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    • pp.95-112
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    • 2008
  • This paper gives the reliability equivalence factors of a parallel system with n independent and non-identical components. It is assumed here that, the failure rates of the system's components are constants. We used three different methods to improve the system given. Two reliability characteristics (the mean time to failure and the reliability function) are used to perform the system improvement. For this purpose, the reliability functions and the mean times to failures of the original and improved systems are obtained. The results given in this paper generalize the results given in the literatures by setting n = 1, 2. An illustrative numerical example is presented to compare the different reliability factors obtained.

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Reliability of a k-out-of-n Cold Standby System with Imperfect Switches

  • Abouammoh, A.M.;Sarhan, Ammar M.
    • International Journal of Reliability and Applications
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    • 제2권4호
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    • pp.253-262
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    • 2001
  • A k-out-of-n standby system is considered where all of its components are s-independent and classified either working or cold standby connected with imperfect switches. The probability density function of the life length for this system is established in closed form, when the underlying components have constant failure rates. Also the reliability function of the system is derived. Finally, the reliability functions for one, two and three out of four systems are deduced for perfect or imperfect switches and identical or non-identical constant failure rates for working and standby components.

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식용 봄꽃(개나리꽃, 진달래꽃, 목련꽃, 벚꽃) 추출물의 항산화성분과 항산화활성 검색 (Screening the Antioxidant Components and Antioxidant Activitiy of Extracts Derived from Five Varieties of Edible Spring Flowers)

  • 김수민;김도연;박혜리;서지혜;염보민;진유정;표영희
    • 한국식품과학회지
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    • 제46권1호
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    • pp.13-18
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    • 2014
  • 우리나라의 대표적인 식용 봄꽃 중 개나리꽃, 진달래꽃, 벚꽃, 목련꽃(백목련, 자목련) 등의 80% 에탄올 추출물에 함유된 항산화 활성성분과 항산화활성을 측정한 결과는 다음과 같다. 5종의 봄꽃 시료의 건물 중량(g of dry weight)에 함유된 생리활성 성분중 총 페놀함량은 gallic acid 등량값으로 14.1-18.9 mg이며, 총 플라보노이드 함량은 catechin 등량값으로 0.3-4.9mg으로 나타났다. 또한 비타민 C의 함량은 0.71-1.31 mg이었으며, 총 카로티노이드 함량은 베타카로틴 등량값으로 $1.9-578.1{\mu}g$으로 나타났으며 프로안토시아니딘의 함량은 카테킨의 등량값으로 2.8-23.5 mg으로 측정되었다. DPPH와 ABTS 라디컬 소거능 및 FRAP 분석의 환원력에 의한 시료의 항산화활성은 건물시료 중량 당 trolox 등량값으로 1.2-46.1 mM로 나타났다(p<0.05). 이들 항산화활성에 상관도($r^2$)가 가장 높은 생리활성 성분은 비타민 C, 플라보노이드, 총 폴리페놀 함량의 순으로 나타나 이들 성분이 항산화활성의 주요인자로 확인되었다. 본 실험에 사용된 5종의 봄꽃 시료 중 항산화활성 성분이 다양하면서 동시에 항산화능이 가장 탁월한 시료는 벚꽃으로 나타났으며(p<0.05), 이들의 항산화활성은 시료 농도(1-1000 mg)에 비례하는 것으로(p<0.05) 나타나, 천연 항산화제 및 기능성 식이소재로서의 잠재적 활용 가능성이 가장 높은 꽃으로 평가되었다.

노래미, Hexagrammos agrammus의 섭식양과 성장양으로부터 에너지 대사의 추정 (Estimation of Energy Budget from Food Consumption and Growth of Hexagrammos agrammus)

  • 김종관;장창익
    • 한국수산과학회지
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    • 제31권1호
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    • pp.121-126
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    • 1998
  • 본 연구는 von Bertalanffy의 성장식과 섭식양을 이용하여 자연조건하에서 노래미, Hexagrammos agrammus의 에너지 대사를 파악하기 위하여 시도된 것이며, 표본은 부산 동백섬 연안과 삼천포 신수도 연안에서 채집된 것이다. 에너지 대사 모델은 섭식양, 함장양, 흡수양, 동화양, 이화양, 배설양, 불소화배출양 등으로 구성된 표준화된 에너지 수지 모델을 이용하였으며, 에너지 대사의 구성요소별 측정단위는 열량단위가 아닌 중량단위로서 나타내 었다. 노래미에 의해 섭식된 연간섭식양이 에너지 대사의 구성요소별 배분되는 양 또는 을은 어체의 연령에 따라 달랐다. 에너지 대사의 구성요소별 추정값을 연령군별로 비교한 결과, 연간배설양은 어체의 연령이 증가할수록 감소하는 경향을 나타내었고, 나머지 구성요소는 어체의 연령이 증가할수록 증가하였다. 연령군별 평균체중 (W)과 연간흡수양($A_b$) 및 연간리화양(R) 간에는 각각 $A_b=4.592W^{0.666}$의 비선형과 R=0.007+0.567W의 선형관계가 있었고, 연간섭식양 (C)과 연간동화양 (A) 및 연간리화양 간에는 각각 A=-7.026+0.061C와 R=-20.749+0.048C의 선형관계가 있었다.

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Effect of Grinding on Color and Chemical Composition of Pork Sausages by Near Infrared Spectrophotometric Analyses

  • Kang, J.O.;Park, J.Y.;Choy, Y.H.
    • Asian-Australasian Journal of Animal Sciences
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    • 제14권6호
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    • pp.858-861
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    • 2001
  • Near Infrared spectroscopy was applied to the samples of processed pork to see the effect of grinding on chemical components analyses. Data from conventional chemical analyses of moisture, fat, protein, NaCl were put into calibration model by NIR of reflectance mode. The other properties observed were pH and color parameters ($L^*,\;a^*,\;b^*$). Spectral ranges of 400~2500 nm and 400~1100 nm were compared for color parameters. Spectral ranges of 400~2500 nm and 1100~2500 nm were compared for chemical components and pH. Different spectral ranges caused little changes in the coefficients of determination or standard errors. $R^{2,}s$ of calibration models for color parameters were in the range of 0.97 to 1.00. $R^{2,}s$ of calibration models of intact sausages for moisture, protein, fat, NaCl and pH were 0.98, 0.89, 0.95, 0.73 and 0.77, respectively using spectra at 1100~2500 nm. $R^{2,}s$ of calibration models of ground sausages for moisture, protein, fat, NaCl and pH were 0.97, 0.91, 0.97, 0.42 and 0.56, respectively using spectra at 1100~2500 nm.

평위산 전탕액의 보관온도 및 기간에 따른 주요성분 및 미생물 군집 변화 (Changes of Principal Components and Microbial Population in Pyungwi-san Decoction according to the Preservation Temperature and Period)

  • 서창섭;신현규;김정훈;신광수
    • 대한한의학회지
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    • 제32권5호
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    • pp.41-49
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    • 2011
  • Objectives: To optimize the preservation method of herbal decoction, we investigated the content of principle components of Pyungwi-san, liquiritin, glycyrrhizin, and hesperidin according to preservation temperature and period. We also investigated the changing patterns of pH and microbial population in Pyungwi-san decoction as a model case. Methods: With samples preserved at different temperatures, the content of liquiritin, glycyrrhizin, and hesperidin was determined using HPLC and microbial population was determined as viable counting method up to 8 times every month. Identification of isolated bacteria was performed by 16S rDNA analysis. Results: The content of liquiritin and glycyrrhizin did not change according to the preservation temperature and period, but that of hesperidin was severely decreased at room temperature. The isolate from the decoction was identified as Bacillus licheniformis by 16S rDNA sequence analysis. Microbial population appeared after 3 months' preservation and reached maximum value at 4 months; at all tested temperatures, the pH showed the lowest value (4.4-4.5) simultaneously. Conclusion: From the results, it seems to be that the microbial growth affects the pH of preserved decoction but not the change of liquiritin and glycyrrhizin content.

Enhanced Antibiotic Production by Streptomyces sindenensis Using Artificial Neural Networks Coupled with Genetic Algorithm and Nelder-Mead Downhill Simplex

  • Tripathi, C.K.M.;Khan, Mahvish;Praveen, Vandana;Khan, Saif;Srivastava, Akanksha
    • Journal of Microbiology and Biotechnology
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    • 제22권7호
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    • pp.939-946
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    • 2012
  • Antibiotic production with Streptomyces sindenensis MTCC 8122 was optimized under submerged fermentation conditions by artificial neural network (ANN) coupled with genetic algorithm (GA) and Nelder-Mead downhill simplex (NMDS). Feed forward back-propagation ANN was trained to establish the mathematical relationship among the medium components and length of incubation period for achieving maximum antibiotic yield. The optimization strategy involved growing the culture with varying concentrations of various medium components for different incubation periods. Under non-optimized condition, antibiotic production was found to be $95{\mu}g/ml$, which nearly doubled ($176{\mu}g/ml$) with the ANN-GA optimization. ANN-NMDS optimization was found to be more efficacious, and maximum antibiotic production ($197{\mu}g/ml$) was obtained by cultivating the cells with (g/l) fructose 2.7602, $MgSO_4$ 1.2369, $(NH_4)_2PO_4$ 0.2742, DL-threonine 3.069%, and soyabean meal 1.952%, for 9.8531 days of incubation, which was roughly 12% higher than the yield obtained by ANN coupled with GA under the same conditions.

3차원 CAD라이브러리를 이용한 프레스 금형 부품의 설계 (A Design of Press Die Components by Use of 3D CAD Library)

  • 박철현;이성수
    • 한국CDE학회논문집
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    • 제9권4호
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    • pp.373-381
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    • 2004
  • Using standard components of a press die is recognized as a way for a cost reduction and a short lead time. It also provides a way for a quick maintenance of a die under repair. It is expected to contribute to integration of CAD/CAM system for manufacturing dies in the future. This paper presents a 3D CAD library which is constructed using the standard components and is used for designing a press die. This 3D CAD library is generated by a database system made of Microsoft Access for standard components and by CATIA V5 R10 API for geometric features. The library is implemented using Visual Basic 6.0 utility of CATIA API function in the Windows NT environment. It creates a 3D model of the standard components of press die easily when a die designer inputs numerical values of geometric features and the BOM of the completely assembled parts. It also generates automatically the assembly drawing of die set by using variables for standard values of die parts. Therefore users can save the cost of time to design the press die components, and even a beginner can use this program with ease. The test results of the 3D CAD library for designing shearing and bending dies verify its usefulness and feasibility.