• Title/Summary/Keyword: Sample orientation

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Evaluation of mechanical and thermal properties of insulation materials for HTS power devices at liquid nitrogen temperature

  • Shin, Hyung-Seop;Diaz, Mark Angelo
    • Progress in Superconductivity and Cryogenics
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    • v.19 no.2
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    • pp.53-57
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    • 2017
  • In superconducting power devices including power cables in which high temperature superconducting (HTS) tapes are utilized, a reliable electrical insulation should be achieved for its maximum performance. For an efficient design of HTS superconducting devices, a comparative evaluation of the mechanical and thermal propperties for various insulation materials at cryogenic temperatures is required. Especially, in the process of the property evaluation of the sheet-shaped insulation materials, anisotropy according to the machining direction should be considered because the mechanical and thermal properties are significantly influenced by the sample orientation. In this study, the cryogenic thermal and mechanical properties of various insulation material sheets such as PPLP, Cryoflex, Teflon, and Kapton were determined considering sample orientation. All samples tested at cryogenic temperature showed significantly higher tensile strength as compared with that of room temperature. The ultimate tensile strength at both temperature conditions significantly depended upon the sample orientation. The thermal properties of the insulation materials exhibited a slight difference among samples depending on the orientation: for the PPLP and Cryoflex, the CD orientation showed larger thermal contraction up to 77 K as compared to the MD one. MD samples in PPLP and Cryoflex showed a lower CTE and thermal contraction which made it more promising as an insulation material due to its comparable CTE with HTS CC tapes.

The Orientation of CO in Heme Proteins Determined by Time-Resolved Mid-IR Spectroscopy: Anisotropy Correction for Finite Photolysis of an Optically Thick Sample

  • Lim, Man-Ho
    • Bulletin of the Korean Chemical Society
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    • v.23 no.6
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    • pp.865-872
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    • 2002
  • A systematic way of determining the equilibrium orientation of carbon monoxide (CO) in heme proteins using time-resolved polarized mid-IR spectroscopy is presented. The polarization anisotropy at pump-probe delay time of zero in the limit of zero photolysis and the angular distrbution function of CO are required to obtain the equilibrium orientation of CO. An approach is developed for determining the polarization anisotropy in the zero-photolysis limit from the anisotropy measured under finite photolysis conditions in an optically thick sample where the fraction of molecules photolyzed decreased as the pump pulse passes through and is absorbed by the sample. This approach is verified by measuring the polarization anisotropy of CO of carbonmonoxy myoglobin at various levels of photolysis. This method can be readily applied to other photoselection experiments determining precise angle between transition dipoles.

The Effect of Market Orientation on Speed-to-market in International Markets

  • Kim, Eunmi
    • East Asian Journal of Business Economics (EAJBE)
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    • v.7 no.1
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    • pp.39-49
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    • 2019
  • Purpose - The major aim of this article is to advance understanding of the relationship between market orientation and speed-to-market. Specifically, this study examines the different impacts of component of market orientation on commitment to R&D and speed-to-market and explores whether market uncertainty plays a role of moderating in speed-to-market for market-oriented firms. Research design, data, and methodology - This study collected a survey data from Korean exporting firms. The Final sample size was 196. The measure of market orientation was conceptualized with second order constructs. All items were measured on five-point scale. To confirm hypotheses, this study conducted a hierarchical regression. Results - As sub-constructs of market orientation, customer orientation, competitor orientation and interfunctional coordination foster speed-to-market, and the relationship between only customer orientation and speed-to-market might be weakened when the extent of market uncertainty is high. Conclusions - This study confirmed the relationship between market orientation and speed-to-market, with three components of market orientation respectively, and whether market uncertainty plays a role of moderating which weaken the link between market orientation and speed-to-market. It could be useful to take a component approach to the market orientation construct, because the roles of different market orientation components might vary, contingent on uncertainty in the environment.

The Role of Strategic Orientation and Social Capital of Founders in the Performance of Korean Startups (창업자의 전략적 지향성과 사회적 자본의 역할)

  • Sohn, Kwonsang;Hur, Wonchang;Sohn, Dong-Won
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.15 no.1
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    • pp.125-141
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    • 2020
  • This study examines the effect of founders' strategic orientation and social capital on the performance of startups in Korean contexts. Founders' strategic orientation is proposed as the main factor to reduce the risk of failure and to increase the potential of future growth of the startup. Three main components of strategic orientation, entrepreneurial, market, technology, were simultaneously tested with a sample of Korean startups. Furthermore, founders' social capital, networks with supporting entities and the level of chemistry within founding members were also proposed to be important factors. We also tested possible mediating effects of social capital on the main impact of strategic orientation. With a sample of 79 startups founded less than 5 years in Seoul Metropolitan Areas, we found that technology orientation of founders only significantly increases the performance of startups, but both entrepreneurial and market orientation do not. Regarding social capital effect, the external networks of the founding members are effective as proposed, and also the high cohesiveness of founding members increases the startup performance. However, the mediating role of social capital is just partially confirmed. The implications of our findings, in both sense of firm's strategy and startup policy, are discussed. This study is expected to be a bridge connecting firms' strategy with startup policy-making in Korea.

Development of Measurement Scale for Clothing Shopping Orientation (Part I) (의복 쇼핑 성향의 측정 도구 개발 (제1보))

  • 김세희;이은영
    • Journal of the Korean Society of Clothing and Textiles
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    • v.28 no.910
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    • pp.1253-1264
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    • 2004
  • The purpose of this study is to develop clothing shopping orientation[CSO] scale reflecting the conceptual structure of CSO. For this purpose, a questionnaire composed of comprehensive 85 CSO items was developed through 2-step preliminary tests. Data was collected from two samples. One sample(n=559) was for scale development and the other sample(n=235) was for cross validity test. Descriptive analysis, correlation analysis, exploratory factor analysis, regression analysis, ANOVA, and confirmatory factor analysis were used for data analysis. For each lower-dimension within the CSO conceptual structure model, 1-2 items were selected based on the quantitative and the qualitative standards. As a result, a CSO scale composed of 31 items was developed, and reliability, construct validity, cross validity, convergent validity, discriminant validity, and criterion validity of the scale were verified. This study has significance in offering the standardized scale to both the academic and the practical fields.

Dependence of Turn-On Voltage and Surface State Density on the Silicon Crystallographic Orientation (실리콘 결정의 방향성에 따른 Turn-On 전사과 추면대융단파의 상대성에 관한 연구)

  • 성영권;성만영;조철제;고기만;이병득
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.33 no.4
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    • pp.157-163
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    • 1984
  • The object of this paper is to investigte the gate controlled diode structure for ionic concentration measurement. It includes device fabrication, characterization, device physics and modeling of the gate controlled diode structure. The differences of turn on voltages and surface generation currents in the (100) and (111) silicon crystallographic orientation of the sample device were observed. Therefore the dependence of these two factors of the silicon crystallographic orientation was investigated. It was observed that drifts arose after extended immersion of the sample device in acid or base solutions. The surface generation-recombination velocity of both (100) and (111) increased. The increase in the interfacial traps for both surface, determined by the turn on voltage was directly proportional to the surface generation-recombination velocity increase.

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The Effect of Learning Organization Construction and Learning Orientation on Organizational Effectiveness among Hospital Nurses (병원간호사의 학습조직화와 학습지향성이 조직유효성에 미치는 영향)

  • Kang, Kyeong-Hwa;Song, Gi-Jun
    • Journal of Korean Academy of Nursing Administration
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    • v.16 no.3
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    • pp.267-275
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    • 2010
  • Purpose: This study conducted to identify the effect of learning organization construction and learning orientation on organizational effectiveness among hospital nurses. Method: Data was collected from convenient sample of 296 nurses who worked for the major hospitals in Seoul, Gyeonggi-do and Gangwoen-do. The self-reported questionnaire was used to assess the general characteristics, the level of the learning organization construction, learning orientation and organizational effectiveness. The data were analyzed using descriptive statistics, pearson's correlation coefficient and multiple regression. Result: The mean score of learning organization construction was 3.61(${\pm}.32$), learning orientation got 3.26(${\pm}.39$), and organizational effectiveness obtained 3.38(${\pm}.42$). The learning organization construction affects of organizational effectiveness by 44.18% and learning orientation by 37.43%. Conclusion: This finding indicates that learning organization construction and learning orientation affects the nurses' organizational effectiveness in hospital.

Physical Features for Way-Finding and Orientation in Specialized Dementia Units (치매노인 특별요양시설내의 길찾기와 방향/현실적응을 위한 물리적 특성)

  • 권오정
    • Journal of the Korean Home Economics Association
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    • v.30 no.4
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    • pp.203-217
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    • 1992
  • From the findings of an exploratory study describing the living environments of segregated Alzheimer/Dementia Units (ADUs), the results relative to environmental cueing reatures, reality orientation aids, and communication/noise control methods are highlighted. Data were collected from a nonrandom, purposive sample of 99 ADUs and their parent long term care facilities in 34 states. Specific recommendations are made about physical features that may assist confused and disoriented residents and contribute to way-finding and orientation in specialized dementia units.

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The Effect of Entrepreneurial Orientation, Learning Orientation and Dynamic Capability on International Performance: Moderating Effects of Slack Resource (중소기업의 기업가지향성, 학습지향성이 동적역량과 국제화 성과에 미치는 영향에 관한 연구: 여유자원의 조절효과를 중심으로)

  • Dong-Woo Ryu;Ki-Keun Kim
    • Korea Trade Review
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    • v.45 no.5
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    • pp.161-179
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    • 2020
  • The importance of entering the international market for small and medium-sized enterprises (SMEs) has been continuously emphasized. As a way to overcome these factors, prior studies have increased interest in dynamic capability. The purpose of this study is to investigate the effects of entrepreneurial orientation, learning orientation, and dynamic capability on their international performance of SMEs. Drawing on an extensive review of the literature on dynamic capability view and internationalization, hypotheses are developed and tested using a sample of 214 SMEs in South Korea. Structural equation modeling was applied. As a result of analysis, first, dynamic capability has a significant effect on international performance. Second, entrepreneurial orientation has significant influence on dynamic capability. Third, learning orientation has significant influence on dynamic capability. Lastly, slack resource was found to moderate the relationship between dynamic capability and international performance. The results indicate that their entrepreneurial orientation and learning orientation ware driver of their dynamic capability. and that their dynamic capability was significant driver of their international performance. In the final conclusion, implications and limitations of research and suggestions for future research are discussed.

Magnetic levitation properties of single- and multi-grain YBCO bulk superconductors

  • Kim, C.J.;Yang, A.Y.;Lee, S.H.;Jun, B.H.
    • Progress in Superconductivity and Cryogenics
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    • v.24 no.3
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    • pp.52-56
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    • 2022
  • Single-grain (c-normal or c-parallel) and multi-grain YBCO superconductors were prepared by a melt growth process with/without seeding. The magnetic levitation force and trapped magnetic field at liquid N2 temperature (77 K) of the YBCO superconductors were investigated. Samples for the levitation force measurement were zero-field cooled (ZFC) to 77 K, and samples for trapped field measurement were field-cooled (FC) using Nd magnets. As for the magnetic levitation force, the c-normal, single grain sample showed the largest value, whereas the multi-grain sample showed the lowest value. The trapped magnetic field of the c-normal and c-parallel single-grain samples was 4-5 times that of the multi-grain sample. In addition, as the external magnetic field (the number of magnets) increased, the both properties increased proportionally. These results were explained in terms of the orientation dependence of the levitation forces and the magnetic field trapping capability of the YBCO superconductor.