• 천문학회보
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• 제43권1호
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• pp.32.2-32.2
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• 2018

We present the structural parameters of ~ 910 dwarf elliptical-like galaxies in the local universe ($z{\lesssim}0.01$) derived from the r-band images of the Sloan Digital SKy Survey (SDSS). We examine the dependence of structural parameters on the morphological types (dS0, dE, dEbc, dSph, and dEblue) and the environment. There is not much difference in the structural parameters among the five subtypes but the mean surface brightness within the effective radius (<${\mu}e$>) of dSph galaxies is clearly different from that of other subtypes. The frequency of disk features such as spiral arm, bar, lens, and rings strongly depends on the morphology of dwarf elliptical-like galaxies with no disk features in dSph galaxies. The absence of disk features and the low surface brightness of dSph galaxies are thought to be closely related to their low mass which leads to different evolution from other subtypes of dwarf elliptical-like galaxies. Density Environments Using IMSNG.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2015년도 제46회 하계학술대회
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• pp.1239-1240
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• 2015

본 논문은 구강내 장치를 이용한 악정형 치료에 있어 환자가 장치를 장착하는 시간과 적용되는 응력과 변형률을 측정하여 치료결과의 완성도를 높이는 데에 있어, 근접무선통신 장치인 NFC(Near Field Communication)를 매개로하여 구강내외 장치의 상태를 모니터링하는 방안에 대한 고찰을 중점적으로 수행하였다. 구강내외에 상태를 계측하기 위한 센서를 설치하고 근접무선통신을 이용하여 병원에서 내원한 환자 상태의 모니터링을 구현하는 시스템을 설계하였으며 무선전력송신 시험을 수행하여 설계변수에 대한 민감도를 살펴보았다.

• Journal of Power Electronics
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• 제13권4호
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• pp.507-515
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• 2013

This paper presents an isolated bidirectional dc/dc converter based on primary parallel isolated boost converter (PPIBC). This topology is an efficient solution in low voltage high power applications due to its ability to handle high currents in the low voltage side. In this paper, the converter has been modeled using non-ideal components and operated without any additional circuitry for startup using a digital soft-start procedure. Simulated and measured loop gains have been compared for the validity of the model. On-the-fly current direction change has been achieved with a prototype interconnecting two battery banks. A second prototype has been constructed and tested for supercapacitor operation in constant power charge mode.

• Clinical and Experimental Pediatrics
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• 제46권10호
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• pp.1036-1039
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• 2003

Sandifer 증후군은 식도의 역류와 관련되어 음식섭취 후 비특이적인 경련과 자세를 취하게 되는 증후군으로서 증상이 경미할 경우 진단이 지연될 수도 있고 여러 신경학적인 질환과 근골격계의 이상과 감별을 위해 과도한 진단과정이 진행될 수도 있다. 저자들은 흡인성 폐렴과 수유 후 무호흡, 비전형적인 경련을 주소로 한 환아에서 Sandifer 증후군을 의심하고 조기에 진단하여 치료한 1례를 보고하는 바이다.

• 한국자동차공학회논문집
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• 제4권3호
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• pp.31-39
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• 1996

The effect of rear-spoiler attached at rear end of automobile trunk on the aerodynamic characteristics of a MIRA reference car model was experimentally investigated. For different shapes and positions(G/H) of the rear-spoiler, the aerodynamic forces on the automobile were measured at various flow speed(ReL). The effect of rear-spoiler on the wake structure behind the automobile was also investigated using flow visualization and hot-wire anemometer. The rear-spoiler modifies the near wake structure and decreases aerodynamic drag and increases driving stability compared with those of the conventional automobile without rear-spoiler. From the experimental results, rear-spoiler of airfoil shape installed at the position of G/H=0.084 shows the best aerodynamic performance.

• 한국자동차공학회논문집
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• 제5권1호
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• pp.136-145
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• 1997

To analyzed ride quality and to predict durability in vehicle dynamics, it is essential to describe a road surface profile precisely. This paper presents a technique to generate road surface profiles in a spatial domain by using a power spectral density function. A single track power spectral density function is proposed to describe a road surface profile, which is also applicable for multi-track vehicle response analysis, The derived road surfaces are compared to ISO(International Organization for Standardization) standards and classifications, proposed by the MIRA(Motor Industry Research Association). The methodology in this paper is also proposed to generate road roughness description with a limited external data. A small amount of external curve data is combined with an internal PSD function to generate road surface roughness in a spatial domain.

• 공학교육연구
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• 제17권6호
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• pp.30-45
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• 2014

Using the data of Economically Active Population Survey and GOMS, we analyze youth employee's labor mobility. We found the causes of the youth employee's labor mobility as follows: work environment, salary, enterprise's vision, job satisfaction, job mismatching, organizational culture, mismatching of work and housing and so on. On the basis of results, we proposed a step by step solutions. The resulting policy implication is that rather than raising job finding rate of the unemployed youths, we need to focus more on reducing job mismatching.

• 천문학회지
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• 제50권4호
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• pp.131-138
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• 2017

We present a new catalog of AGB stars based on infrared two-color diagrams (2CDs) and known properties of the pulsations and spectra. We exclude some misclassified objects from previous catalogs. We identify color areas in two IR 2CDs where most O-rich and C-rich objects listed in previous catalogs of AGB stars are found. By collecting new objects in these color selection areas in the two IR 2CDs, we find candidate objects for AGB stars. By using the color selection method, we identify 3996 new objects in the O-rich areas, 1487 new objects in the C-rich areas, and 295 new objects in the overlap areas of the two 2CDs simultaneously. We have found that 470 O-rich and 9 C-rich objects are Mira variables with positive spectral identification and they are newly identified AGB stars. We present a new catalog of 3828 O-rich AGB stars and 1168 C-rich AGB stars excluding misclassified objects and adding newly identified objects.

• Carbon letters
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• 제15권1호
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• pp.67-70
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• 2014

In this work, nanocomposites of epoxy resin and chemically reduced graphene oxide (RGO) were prepared by thermal curing process. X-ray diffractions confirmed the microstructural properties of RGO. Differential scanning calorimetry was used to evaluate the curing behaviors of RGO/epoxy nanocomposites with different RGO loading amounts. We investigated the effect of RGO loading amounts on the mechanical properties of the epoxy nanocomposites. It was found that the presence of RGO improved both flexural strength and modulus of the epoxy nanocomposites till the RGO loading reached 0.4 wt%, and then decreased. The optimum loading achieved about 24.5 and 25.7% improvements, respectively, compared to the neat-epoxy composites. The observed mechanical reinforcement might be an enhancement of mechanical interlocking between the epoxy matrix and RGO due to the unique planar structures.

• 한국동물학회지
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• 제24권1호
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• pp.38-57
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• 1981

Cardell, Jr. (1964)는 도룡뇽의 뇌하수체 전염에서 5가지의 분비세포를 구분하였으며 Dent와 Gupta (1967), 그리고 Iturrza (1964)는 영원류에서 5가지 분비세포를 구분하여 보고한 바 있다. 또 Doerr-Schott (1965)는 개구리에서 5가지 분비세포를, Mira-Moser (1969, 1970)는 6가지의 분비세포와 한가지의 무과립세포를 구분하였다. Shinkawa등 (1972)도 역시 7가지 cell type을 구분하였다. Shinkawa와 Nakai (1972)는 참개구리에서 역시 7가지 cell type을, 그리고 이들이 선정한 3 cell type에서 ACTH를 분비한다는 사실을 보고 하였다. 이에 본 연구자들은 산개구리를 재료로 하여 우선 동면기의 것을 실험하였던 바 7가지 cell type을 구분한 바 있고, 다시 활동기의 것을 재료로하여 세포내 소기관의 변화를 관찰하였는데 여기서 몇가지 차이점을 보고하는 바이다.