• 제목/요약/키워드: Core Center

검색결과 2,385건 처리시간 0.049초

Dense Core Formation in Filamentary Clouds: Accretion toward Dense Cores from Filamentary Clouds and Gravitational Infall in the Cores

  • Kim, Shinyoung;Lee, Chang Won;Myers, Philip C.;Caselli, Paola;Kim, Mi-Ryang;Chung, Eun Jung
    • 천문학회보
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    • 제44권1호
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    • pp.70.3-70.3
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    • 2019
  • Understanding how the filamentary structure affects the formation of the prestellar cores and stars is a key issue to challenge. We use the Heterodyne Array Receiver Program (HARP) of the James Clerk Maxwell Telescope (JCMT) to obtain molecular line mapping data for two prestellar cores in different environment, L1544 in filamentary cloud and L694-2 in a small cloud isolated. Observing lines are $^{13}CO$ and $C^{18}O$ (3-2) line to find possible flow motions along the filament, $^{12}CO$ (3-2) to search for any radial accretion (or infalling motions) toward the cores of gas material from their surrounding regions, and $HCO^+$ (4-3) lines to find at which density and which region in the core gases start to be in gravitational collapse. In the 1st moment maps of $^{13}CO$ and $C^{18}O$, velocity gradient patterns implying the flow of material were found at the cores and its surrounding filamentary clouds. The infall asymmetry patterns of HCO+ and $^{13}CO$ line profiles were detected to be good enough to analyze the infalling motions toward the cores. We will report further analysis results on core formation in the filamentary cloud at this meeting.

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비정형 구조물의 평면 회전축과 코어의 이동에 따른 지진응답분석 (Analysis of Seismic Response by the Movement of the Plane Rotation Axis and the Core of Atypical Structures)

  • 이다혜;김현수;강주원
    • 한국공간구조학회논문집
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    • 제22권1호
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    • pp.33-40
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    • 2022
  • When the center of stiffness and the center of mass of the structure differ under the seismic load, torsion is caused by eccentricity. In this study, an analysis model was modeled in which the positions of the core and the plane rotation axis of a 60-story torsional atypical structure with a plane rotation angle of 1 degree per floor were different. The structural behavior of the analysis model was analyzed, and the earthquake response behavior of the structure was analyzed based on the time history analysis results. As a result, as the eccentricity of the structure increased, the eccentricity response was amplified in the high-rise part, and the bending and torsional behavior responses were complex in the low-order vibration mode. As a result of the analysis, the maximum displacement and story drift ratio increased due to the torsional behavior. The maximum story shear force and the story absolute maximum acceleration showed similarities for each analysis model according to the shape of the vibration mode of the analysis model.

Thermomechanical behavior of Macro and Nano FGM sandwich plates

  • Soumia, Benguediab;Tayeb, Kebir;Fatima Zohra, Kettaf;Ahmed Amine, Daikh;Abdelouahed, Tounsi;Mohamed, Benguediab;Mohamed A., Eltaher
    • Advances in aircraft and spacecraft science
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    • 제10권1호
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    • pp.83-106
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    • 2023
  • In this work, the static behavior of FGM macro and nano-plates under thermomechanical loading. Equilibrium equations are determined by using virtual work principle and local and non-local theory. The novelty of the current model is using a new displacement field with four variables and a warping function considering the effect of shear. Through this analysis, the considered sandwich FGM macro and nanoplates are a homogeneous core and P-FGM faces, homogeneous faces and an E-FGM core and finally P-FGM faces and an E-FGM core. The analytical solution is obtained by using Navier method. The model is verified with previous published works by other models and very close results are obtained within maximum 1% deviation. The numerical results are performed to present the influence of the various parameters such as, geometric ratios, material index as well as the scale parameters are investigated. The present model can be applicable for sandwich FG plates used in nuclear, aero-space, marine, civil and mechanical applications.

대학생 핵심역량 진단도구의 개발과 타당화 연구 : M대학교를 중심으로 (Development and Validation of a Scale for Diagnosing the Core Competency of University Students: M University Case Study)

  • 이미라;김누리
    • 해양환경안전학회지
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    • 제24권5호
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    • pp.576-582
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    • 2018
  • 현재 우리나라의 대학들은 사회에서 요구하는 능력과 태도를 갖추고 이를 준비할 수 있는 인재를 키우기 위해 노력 중이며 이 중 많은 대학들이 핵심역량 기반의 교육을 실시하고 있다. 이에 학생들의 핵심역량을 객관적으로 측정하여 교육성과를 확인할 필요성이 제기되고 있으며 이를 진단할 수 있는 도구들을 개발하고 있다. 전문화된 해양인력을 양성하는 M대학의 경우에도 대학의 특수성을 반영한 핵심역량 기반 교육을 실시하고 있다. 따라서 본 연구에서는 M대학의 핵심역량을 측정할 수 있는 도구를 개발하고 이를 타당화 하는 것이 목적이다. 이를 위해 첫째, 문헌고찰을 중심으로 예비문항을 개발하였고, 둘째, 문항분석 및 탐색적 요인분석을 실시하였다. 그 결과 6개의 구성요소를 도출하였다. 마지막으로 최종 검사를 실시하여 총 52개의 문항이 도출되었고 이에 대한 타당성 여부를 확보하였다. 본 연구를 바탕으로 개발한 검사 도구는 학생들의 핵심역량 수준을 진단할 뿐만 아니라 개별 핵심역량 수준을 진단하여 프로그램을 연계할 수 있으며, 궁극적으로 해사 및 해양 특성화를 갖춘 대학의 차별화된 인재를 기르기 위한 기초자료로 사용 가능할 것이다.

Cell Death and Stress Signaling in Glycogen Storage Disease Type I

  • Kim, So Youn;Bae, Yun Soo
    • Molecules and Cells
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    • 제28권3호
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    • pp.139-148
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    • 2009
  • Cell death has been traditionally classified in apoptosis and necrosis. Apoptosis, known as programmed cell death, is an active form of cell death mechanism that is tightly regulated by multiple cellular signaling pathways and requires ATP for its appropriate process. Apoptotic death plays essential roles for successful development and maintenance of normal cellular homeostasis in mammalian. In contrast to apoptosis, necrosis is classically considered as a passive cell death process that occurs rather by accident in disastrous conditions, is not required for energy and eventually induces inflammation. Regardless of different characteristics between apoptosis and necrosis, it has been well defined that both are responsible for a wide range of human diseases. Glycogen storage disease type I (GSD-I) is a kind of human genetic disorders and is caused by the deficiency of a microsomal protein, glucose-6-phosphatase-${\alpha}$ ($G6Pase-{\alpha}$) or glucose-6-phosphate transporter (G6PT) responsible for glucose homeostasis, leading to GSD-Ia or GSD-Ib, respectively. This review summarizes cell deaths in GSD-I and mostly focuses on current knowledge of the neutrophil apoptosis in GSD-Ib based upon ER stress and redox signaling.

단축형 ICF 핵심지표로 측정한 뇌졸중 환자의 기능상태 (Assessing the Functional Status of Acute Stroke Patients using ICF Core Set-short Form)

  • 강지연;공주;박미진;이여원;김유리
    • 근관절건강학회지
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    • 제20권1호
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    • pp.22-30
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    • 2013
  • Purpose: The International Classification of Functioning, Disability and Health (ICF) model was proposed by the World Health Organization for enhancing interdisciplinary communication. The purpose of this study was to examine the functional status of acute stroke patients using ICF core sets-short form. Methods: A set of 15 ICF items on functional status was used by nurses for their daily nursing assessment on functional status in 44 acute stroke patients in a university hospital. Results: The highest level of function was "consciousness", while the lowest was "defecation". Compared with functional status on the first day, consciousness, ingestion, language (mental), and defecation functions were significantly improved on the 14th day. However, there was no significant changes in items on activity and participation or environmental functions. Conclusion: These findings suggest that the function-specific nursing interventions for acute stroke patients need to be developed. Future research needs to test the usefulness of ICF items as an measurement tool.

Cereal Resources in National BioResource Project of Japan

  • Sato, Kazuhiro;Endo, Takashi R.;Kurata, Nori
    • Interdisciplinary Bio Central
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    • 제2권4호
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    • pp.13.1-13.8
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    • 2010
  • The National BioResource Project of Japan is a governmental project to promote domestic/international research activities using biological resources. The project has 27 biological resources including three cereal resources. The core center and sub-center which historically collected the cereal resources were selected for each cereal program. These resources are categorized into several different types in the project; germplasm, genetic stocks, genome resources and database information. Contents of rice resources are wild species, local varieties in East and Southwest Asia & wild relatives, MNU-induced chemical mutant lines, marker tester lines, chromosome substitution lines and other experimental lines. Contents of wheat resources are wild strains, cultivated strains, experimental lines, rye wild and cultivated strains; EST clones and full-length cDNA clones. Contents of barley resources are cultivar and experimental lines, core collection, EST/cDNA clones, BAC clones, their filters and superpool DNA. Each resource is accessible from the online database to see the contents and information about the resources. Links to the genome information and genomic tools are also important function of each database. The major contents and some examples are presented here.

솔레노이드 액추에이터의 비선형 동적응답에 대한 구조최적설계 (Structural Optimization for Nonlinear Dynamic Response of Solenoid Actuator)

  • 백석흠;김현수;장득열;이승범;권영석;노의동;이창훈
    • 한국자동차공학회논문집
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    • 제21권1호
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    • pp.113-120
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    • 2013
  • This paper proposes a design optimization approach for core of solenoid actuators by combining optimization techniques with the finite element method (FEM). A solenoid is an important element part which hydraulically controls a transmission system, etc. The demanded feature of the solenoid is that it performs an electromagnetic force output being constant regardless of the stroke and being proportional to coil current. The plunger compresses a spring with a minimum force of 12 N over an 1.7 mm travel. The orthogonal array, analysis of variance (ANOVA) techniques and response surface optimization, are employed to determine the main effects and their optimal design variables. The methodology is demonstrated as a optimization tool for the core design of a solenoid actuator.

저손실 자심재료를 이용한 평면변압기 제조 및 동작특성 (Manufacture and Characteristics of the Planar Transformer using low power loss magnetic materials)

  • 이해연;허정섭;김현식;박혜영
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2004년도 춘계학술대회 논문집 방전 플라즈마 유기절연재료 초전도 자성체연구회
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    • pp.19-22
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    • 2004
  • The resonant planar transformer, which had power capacity of 300 W, input voltage of 220 V, output voltage of 15 V, and switching frequency of 500 kHz, was designed and manufactured by using the planar core with large effective area and the flat copper lead frames for miniaturization and high efficiency of the switching mode power supply (SMPS). As well as, a resonant converter equipped with the above mentioned planar transformer was manufactured and electromagnetic characteristics were investigated. The numerical value of turns for 1st and 2nd winding were 12 and 2 respectively. The self inductance of 1st winding was 33.2 ${\mu}H$, very low leakage inductance of 1.27 ${\mu}H$, and the coupling factor of 0.98 were obtained at switching frequency of 300 kHz. The high efficiency of 88.21 % for the SMPS equipped with planar transformer was obtained at power capacity of 300 W.

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High-Speed BLDC Motor Design for Suction Fan and Impact on the Loss caused by Core Welding

  • Hong, Hyun-Seok;Kim, In-Gun;Lee, Ho-Joon;Go, Sung-Chul;Lee, Ju
    • Journal of Electrical Engineering and Technology
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    • 제12권1호
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    • pp.126-133
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    • 2017
  • This paper deals with the effects of welding, which is done to fix the stator stack, on a motor in case of fabricating a prototype motor that is manufactured in a small quantity. In the case of a small motor, the stator is designed and fabricated with the segmented core as a way to raise the fill factor of winding wire to the utmost within a limited size. In case of fabrication by welding both inside and outside of the stator in order to fix the segmented-core stator, the effects of stack are ignored, and the eddy current loss occurs. This paper performed the no-load test on an IPM-type BLDC motor for driving the suction fan of a vacuum cleaner, which was manufactured by using a segmented-core stator. As a result of the test, it was found that input power more than expected was supplied. To analyze the effects of welding by using the finite element analysis method and verify them experimentally, a stator was re-manufactured by bonding, and input power supplied during the no-load test was compared.