• Title/Summary/Keyword: Mass Generation

검색결과 829건 처리시간 0.028초

Variations in the Na-O anticorrelation in globular clusters

  • Lee, Jae-Woo
    • 한국우주과학회:학술대회논문집(한국우주과학회보)
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    • 한국우주과학회 2010년도 한국우주과학회보 제19권1호
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    • pp.27.1-27.1
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    • 2010
  • The Na-O anticorrelation seen in almost all globular clusters ever studied using high-resolution spectroscopy is now generally explained by the primordial pollution from the first generation of the intermediate-mass AGB stars to the proto-stellar clouds of the second generation of stars. Using the recent data by Carretta and his collaborators, the different shapes of the Na-O anticorrelations for RGB stars brighter than and fainter than the red giant branch bump can be clearly seen. If the elemental abundance measurements by Carretta and his collaborators are not greatly in error, this variation in the Na-O anticorrelation against luminosity indicates an internal deep mixing episode during the ascent of the low-mass RGB in globular clusters. Our result implies that the multiple stellar population division scheme solely based on [O/Fe] and [Na/Fe] ratios of a globular cluster, which is becoming popular, is not reliable for stars brighter than the RGB bump.

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IoT 시대 효과적인 커뮤니케이션을 위한 스마트미러 UX 평가 연구 (Evaluation Research on Smart Mirror UX for Efficient Communication of the IoT Generation)

  • 오문석
    • 디지털산업정보학회논문지
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    • 제11권1호
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    • pp.121-133
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    • 2015
  • IoT utilized network vitalization between objects are being rapidly established within current IT communication environment. Therefore the worth of smart mirrors is rising for it is a tool to allow online network between objects to be possible in human communication environment. For effective IoT generation's communication, this research intends to evaluate the smart mirror's value for practical uses based on the users' experiences. For the UX evaluation according to the locations where it will be used, Peter Morville's Honeycomb model and Jocob Nielsen's usage evaluation principles were referred to analyze effectiveness of 4 factors, utilization convenience, communication effectiveness, mass interest and space adequateness on households, public places and work places. Hence, we have were led to an objective result through statistical analysis method based on survey. As a result, we have confirmed the smart mirror's positive influence on the users' effective communication in all places. Especially in households, utilization convenience and space adequateness appeared to be high that confirmed sufficient users' need for the home-automation services. In public places, the communication effectiveness and space adequateness ranked high to confirm that the smart mirror utilization is adequate to provide location information. Also, in work places, the mass adequateness was high that we were able to confirm that supply of work place-specific service contents would bring meaningful results to the users. The smart mirrors are the adequate method to provide effective communication in IoT generation with high possibilities in further development.

전기화학 반응에 의한 생성 열의 단순화된 처리 기법을 이용한 평판형 고체산화물 연료전지 내부의 이동현상에 대한 전산 해석 (Computational Analysis of Transport Phenomena in a Planar-Type Solid Oxide Fuel Cell with a Simplified Treatment of the Electrochemical Heat Generation)

  • 차훈;손정락;노승탁
    • 한국세라믹학회지
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    • 제42권12호
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    • pp.846-853
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    • 2005
  • For the performance prediction of a planar-type solid oxide fuel cell, the computational analysis of transport phenomena with a simplified treatment of heat generation by the electrochemical reaction is conducted. From the result of the computational analysis, it is shown that the electrochemical reaction is closely related to the transport phenomena inside a solid oxide fuel cell. Transport phenomena including heat and mass transfer influences on the distribution of local current density and, as a result, on the performance characteristics of the fuel cell. Computational analysis is also extended to the parametric study to investigate the performance behavior of the fuel cell with different amount of supplied fuel flow rates. It is also demonstrated that the mathematical formulation and computational procedures proposed in this study can be applied to prove the importance of the specific TPB area in the manufacturing process of electrodes in solid oxide fuel cells.

1960년대(年代) 영 패션이 현대(現代) 패션산업(産業)에 미친 영향(影響) (A Study on the Influences on the Contemporary Fashion Industry of the 60s Young Fashion)

  • 최비숙;조규화
    • 패션비즈니스
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    • 제2권2호
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    • pp.11-25
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    • 1998
  • The purpose of this paper is to investigate how the young fashion which maintains a large share of fashion market emerged in the 1960s, its characteristics and what its influences on the contemporary fashion industry are. In particular, I am going to consider the significance of the young fashion by looking at the formation of niche market, the emergence of mass market for fashion, the expansion of aesthetic categories. we will be able to see the 60s young fashion of the young generation who emerged as new consumers in mass consumer culture exerted important influences on the contemporary fashion industry. First, the counterculture of young generation who rebeled against the uniformity of mass production helped the formation of new niche market. Second, the young fashion which pursued the lower prices for fashion made a big contribution to the popularization of fashion. The young generations tendency to demand new things and rapid change coincided with that of inexpensive popular fashion people can buy and change more easily than expensive high fashion. Lastly, the playful tendency of the young fashion expanded the aesthetic boundaries of the clothing, going beyond the uniformity of modernism with the emergency of diverse fashion materials - fabric and textiles - enable by technological development and the miniaturization of forms as revealed in mini skirt.

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시멘트 및 거푸집 종류에 따른 매스콘크리트의 내구성 및 수화발열특성에 관한 실험적 연구 (An Experimental Stuty on Mass Concrete Durability & Hydration Heat Generation Characteristics according to Kinds of Cement & Form)

  • 김강민;문상봉;송용순;강석화;최삼순;조용연
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2009년도 춘계 학술대회 제21권1호
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    • pp.359-360
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    • 2009
  • 본 연구는 실제 현장 적용 타설고를 고려한 Mock-up 시험을 통해 슬래그 시멘트와 저발열 시멘트 및 유로폼과 리브라스 거푸집 적용에 따른 매스콘크라트의 거동을 알아보고자 하였다. 먼저 시험체의 수화열 계측을 실시하여 각각의 수화발열특성을 살펴보았다. 모르타르 유출량 시험, 코어 및 표준수중양생 공시체의 압축강도, 염소이온침투저항생시험을 통한 내구성을 비교하여 해양 환정에 노출된 매스콘크리트 타설 시 공기단축 및 수화열 저감, 내구성 확보와 같은 안정적 품질확보를 위한 기초자료를 제공하는데 그 목적을 두었다.

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Nuclear waste attributes of near-term deployable small modular reactors

  • Taek K. Kim;L. Boing;B. Dixon
    • Nuclear Engineering and Technology
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    • 제56권3호
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    • pp.1100-1107
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    • 2024
  • The nuclear waste attributes of near-term deployable SMRs were assessed using established nuclear waste metrics, which are the DU mass, SNF mass, volume, activity, decay heat, radiotoxicity, and decommissioning LLW volumes. Metrics normalized per unit electricity generation were compared to a reference large PWR. Three SMRs, VOYGR, Natrium, and Xe-100, were selected because they represent a range of reactor and fuel technologies and are active designs deployable by the decade's end. The SMR nuclear waste attributes show both some similarities to the PWR and some significant differences caused by reactor-specific design features. The DU mass is equivalent to or slightly higher than the PWR. Back-end waste attributes for SNF disposition vary, but the differences have a limited impact on long-term repository isolation. SMR designs can vary significantly in SNF volume (and thus heat generation density). However, these differences are amenable to design optimization for handling, storage, transportation, and disposal technologies. Nuclear waste attributes from decommissioning vary depending on design and decommissioning technology choices. Given the analysis results in this study and assuming appropriate waste management system and operational optimization, there appear to be no major challenges to managing SMR nuclear wastes compared to the reference PWR.

Comparable Electron Capture Efficiencies for Various Protonated Sites on the 3rd Generation Poly(Propylene Imine) Dendrimer Ions: Applications by SORI-CAD and Electron Capture Dissociation Mass Spectrometry (ECD MS)

  • Han, Sang-Yun;Lee, Sun-Young;Oh, Han-Bin
    • Bulletin of the Korean Chemical Society
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    • 제26권5호
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    • pp.740-746
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    • 2005
  • In this article, we report the tandem mass spectrometry investigations for the electron capture efficiencies of the protons belonging to the different locations (generations) in a poly(propylene imine) dendrimer with three layers of a repeat unit (named as the third generation dendrimer). The employed tandem mass spectrometry methods include SORI-CAD (sustained off-resonance irradiation collisional activation dissociation) and ECD(electron capture dissociation) mass spectrometry. We obtained SORI-CAD spectra for the dendrimer ions in the different charge states, ranging from 2+ to 4+. The analysis of fragmentation sites provides the information as to where the protons are distributed among various generations of the dendrimer. Based upon this, a new strategy to study the electron capture efficiencies of the protons is utilized to examine a new type of triplycharged ions by SORI-CAD, i.e., the 3+ ions generated from the charge reduction of the native 4+ ions by ECD: (M+4H)$^{4+}\;+\;e^-\;{\rightarrow}$ (M+4H)$^{3+\bullet}$ ${\rightarrow}\;({H^{\bullet}}_{ejected}$) + (M+3H)$^{3+}\;\rightarrow$ CAD. Interestingly, comparison of these four SORICAD spectra indicates that the proton distribution in the charge-reduced 3+ ions is very close to that in the native 4+ ions. It further suggests that in this synthetic polymer ($\sim$1.7 kDa) with an artificial architecture, the electron capture efficiencies of the protons are actually insensitive to where they are located in the molecule. This is somewhat contradictory to common expectations that the protons in the inner generations may not be well exposed to the incoming electron irradiation as much as the outer ones are, thus may be less efficient for electron capture. This finding may carry some implications for the case of medium sized peptide ions with similar masses, which are known to show no obvious site-specific fragmentations in ECD MS.

Dubins 곡선을 이용한 항공기 3자유도 질점 모델의 3차원 경로계획 및 유도 (3-Dimensional Path Planning and Guidance using the Dubins Curve for an 3-DOF Point-mass Aircraft Model)

  • 오수헌;하철수;강승은;목지현;고상호;이용원
    • 한국항공운항학회지
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    • 제24권1호
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    • pp.1-9
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    • 2016
  • In this paper, we integrate three degree of freedom(3DOF) point-mass model for aircraft and three-dimensional path generation algorithms using dubins curve and nonlinear path tracking law. Through this integration, we apply the path generation algorithm to the path planning, and verify tracking performance and feasibility of using the aircraft 3DOF point-mass model for air traffic management. The accuracy of modeling 6DOF aircraft is more accurate than that of 3DOF model, but the complexity of the calculation would be raised, in turn the rate of computation is more likely to be slow due to the increase of degree of freedom. These obstacles make the 6DOF model difficult to be applied to simulation requiring real-time path planning. Therefore, the 3DOF point-mass model is also sufficient for simulation, and real-time path planning is possible because complexity can be reduced, compared to those of the 6DOF. Dubins curve used for generating the optimal path has advantage of being directly available to apply path planning. However, we use the algorithm which extends 2D path to 3D path since dubins curve handles the two dimensional path problems. Control law for the path tracking uses the nonlinear path tracking laws. Then we present these concomitant simulation results.

탠덤 질량 분석을 위한 디코이 데이터베이스 생성 방법의 중복성 관점에서의 성능 평가 (Evaluation of the Redundancy in Decoy Database Generation for Tandem Mass Analysis)

  • 이홍란;류단휘;이기욱;황규백
    • 정보과학회 컴퓨팅의 실제 논문지
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    • 제22권1호
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    • pp.56-60
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    • 2016
  • 탠덤 질량 분석에서는 신뢰도 높은 펩타이드 동정을 위해 목표 데이터베이스의 참조 단백질 순서를 재배치한 디코이 데이터베이스가 주로 이용된다. 한편 목표 데이터베이스와 디코이 데이터베이스 사이 혹은 디코이 데이터베이스 내부에 서열이 동일한 중복 펩타이드가 존재할 수 있으며, 이는 단백질 동정을 어렵게 하는 요인이 된다. 따라서 디코이 데이터베이스의 중복성을 최소화하는 것은 중요한 문제이다. 본 논문에서는 디코이 데이터베이스 생성에 널리 사용되는 의사셔플(pseudo-shuffling)과 의사역순(pseudo-reversing) 방법이 디코이 데이터베이스의 중복성에 미치는 영향을 조사하였다. 실험 결과, 목표 데이터베이스 크기와 데이터베이스 생성 시 허용되는 'missed cleavage site'의 최대 개수는 중복성을 증가시킴을 확인하였다. 또한 동일한 조건에서는 의사역순 방법이 의사셔플보다 항상 낮은 수준의 중복성을 가지는 디코이 데이터베이스를 생성하였다.