• Title/Summary/Keyword: OTI

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A study on the measurement of thermophysical properties of BaOTiO$_{2}$, SrOTiO$_{2}$, MgOTiO$_{2}$ series by a single rectangular pulse heating (방형파 펄스 가열에 의한 BaOTiO$_{2}$ SrOTiO$_{2}$, MgOTiO$_{2}$ 계열의 열물성치 측정에 관한 연구)

  • 차경옥;장희석;이흥주
    • Journal of the korean Society of Automotive Engineers
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    • v.13 no.2
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    • pp.88-102
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    • 1991
  • In this study, thermophysical properties of the ceramic dielectrics such as BaOTiO$_{2}$, SrOTiO$_{2}$, MgOTiO$_{2}$, were measured by a single rectangular pulse heating method. The values of thermal diffusivities, specific heats, and thermal conductivities were measured as a function of temperature range from room temperature to 1300k. The measured thermal properties of one group of ceramic material were compared with those of other group and discussed in detail in connection with the chemical composition. Thus, some criteria for thermal design with the electric-electronic ceramic material were proposed.

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Synthesis of ArOTiCl3 complexes and their application for ethylene polymerization and copolymerization

  • Wang, Jianwei;Ren, Yingchun;Xu, Sheng;Mi, Puke
    • Advances in materials Research
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    • v.6 no.3
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    • pp.303-316
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    • 2017
  • In this article, novel olefin polymerization catalyst with lower cost and simple synthetic process were developed, $ArOTiCl_3$ complexes [$(2-OMeC_6H_4O)TiCl_3(C1)$, $(2,4-Me_2C_6H_3O)TiCl_3(C2)$, $TiCl_3(1,4-OC_6H_4O)TiCl_3(C3)$, $TiCl_3(1,4-OC_6H_2O-Me_2-2,5)$ $TiCl_3(C4)$] and corresponding $(ArO)_2TiCl_2$ complexes [$TiCl_2(OC_6H_4-OMe-2)_2(C5)$ and $TiCl_2(OC_6H_3-Me_2-2,6)_2(C6)$] have been synthesized by the reaction of $TiCl_4$ with phenol, all these complexes were well characterized with $^1H$ NMR, $^{13}C$ NMR, MASS and EA. When combined with methylaluminoxane (MAO), the $ArOTiCl_3/MAO$ system shows high activity for ethylene copolymerization with 1-octene and copolymer was obtained with broaden molecular weight distribution (MWD). The $^{13}C$ NMR result of polymer indicates that the 1-octene incorporation in polymer reached up to 8.29 mol%. The effects of polymerization temperature, concentration of polymerization monomer and polymerization time on the catalytic activity have been investigated.

Study on the Freight Forwarding System of Advanced Shipping Country - A Case of United States of America System - (선진 해운국의 Freight Forwarding System에 관한 연구 - 미국제도를 중심으로 -)

  • Kim, Se-Won
    • Journal of Fisheries and Marine Sciences Education
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    • v.20 no.3
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    • pp.416-428
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    • 2008
  • In the end of 2007, Korea Government promulgated the Rule of 'Basic Act of Logistics Policy' for improving international logistics forwarding business. The goals of these rules are to achieve the development of our nation's economics for providing the security and efficiency of logistics system and enforced competition of logistics enterprises. This is established the basic principles of the legal basis for expanding into the Logistics Hub Center of North-east Asia. However In May 1999 new licensing requirements for ocean freight forwarders and NVOCCs operating in the USA were established by the US Federal Maritime Commission(FMC). Due to these regulations, each ocean transportation service provider in the USA acting as ocean freight forwarder, NVOCCs, or NVOCC agent must obtain a license to operate as Ocean Transportation Intermediary(OTI) before it begins operations. Only licensed OTIs may act as US transportation agents or receiving agents of other NVOCCs, on both US exports and imports. In this context, I think this study will be contributes for the development of korean freight forwarding system by analysis and comparing with between the Rule of the Basic Act of Logistics Policy of Korea and OTI freight forwarder & NVOCCs of USA.

A study on vibration characteristics caused by backlash of gear-box in escalator with chain-sprocket drive mechanism (체인-스프라켓 메커니즘을 갖는 에스컬레이터에서 기어박스 백래시로 인한 이상진동에 관한 연구)

  • Kwon, Yi-Sug;Park, Seon-Ryong;Suh, Jong-Ho;Hong, Seong-Wook;Park, No-Gil
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.11a
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    • pp.329.2-329
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    • 2002
  • This paper presents an improved escalator dynamic model so as to reflect the experimental observation on the pseudo-resonance affected by load applied. The experimental evidence reveals that backlash of gearbox as well as sag of driving chain are most critical factors to the pseudo-resonance in escalators. The dynamic model effectively reflects vibration characteristics measured in real escalators with respect to different conditions of driving chain and the number of passengers. (omitted)

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Effects of Nurses' Self-leadership and Team Trust on Organizational Commitment (병원간호사의 셀프리더십과 팀 신뢰성이 조직몰입에 미치는 영향)

  • Kim, Se Young;Kim, Eun-Kyung;Kim, Byungsoo
    • Journal of Korean Academy of Nursing Administration
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    • v.22 no.4
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    • pp.353-361
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    • 2016
  • Purpose: The purpose of this study was to investigate the association between self-leadership, team trust, organizational commitment and identify the influencing factors on organizational commitment. Methods: The subjects in the study were 296 conveniently selected general nurses at 2 general hospitals in Chungbuk Province. The measurements included the self-leadership, organizational trust inventory (OTI), and organizational commitment. Results: The mean score for self-leadership was 3.40, the mean score for OTI was 3.61, and the mean score for organizational commitment was 3.07. There were significant correlations among self-leadership, team trust and organizational commitment. Self-leadership had significant correlation with team trust (r=.25, p<.001). Also, self-leadership (r=.34, p<.001) and team trust (r=.31, p<.001) showed significant correlation with organizational commitment. In stepwise multiple regression analysis, age, self-leadership and team trust were included in the factors affecting organizational commitment of clinical nurses. These variables explained 20% of organizational commitment. Conclusion: The results confirmed that nurses' self-leadership and team trust affects significant influences on organizational commitment. Accordingly, in order to enhance nurses' organizational commitment, it is necessary to build effective strategies to enhance self-leadership and team trust for nurses. Such strategies will be able to improve the goal achievement of nursing unit.

Technology Investment Propensity Factors Related on the Technology Competitive Advantage and Business Performance, and the Role of Open Technology Innovation (기술 경쟁우위 및 경영성과에 영향을 미치는 기술 투자성향 특성요인과 개방형 기술혁신의 역할)

  • Shin, Seung Hoon;Ahn, Yeon S.
    • Journal of Information Technology Applications and Management
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    • v.23 no.4
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    • pp.71-82
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    • 2016
  • The purpose of this study is to prove empirically that technology investment propency factors (TIPFs) refect on the technological competitive advantage (TCA) and management performance. It includes the role of open technology innovation (OTI) approach is mediate to TCA from technology investment propensity. Especially the three TIPFs are market orientation, innovation orientation and strategy orientation. The analysis were performed based on the respondents' data from 181 firms focusing to technology innovation and information technology. The suggested research assumptions including structured equation model were proved. Therefore, this study emphasizes that CEO or CTO must concentrate on innovative, strategic and market oriented propensity when he makes a decision on technology investment. An open innovation approach is effective for getting high TCA and management performance in technology intensive firms such as technology innovation and information technology.

사고사례를 통한 승객용 승강기의 재해예방대책

  • 윤유성;권오헌;고성석
    • Proceedings of the Korean Institute of Industrial Safety Conference
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    • 2001.11a
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    • pp.349.1-357
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    • 2001
  • 안전장치가 설치된 승강기는 1857년 Otis에 의해 개발되어 최근 건물의 고층화에 따른 사람들의 수직 및 수평 운송수단으로서 우리들의 일상적인 생활에 없어서는 안 될 시설임에도 불구하고 그 이용에 따른 안전사고가 발생하고 있다. 1993년부터 2000년까지 한국승강기안전관리원$^{1)}$ 에 따른 승강기 안전사고 발생현황은 총 승강기 설치대수에 대한 년 평균 재해발생율이 0.0414%로 총 안전사고 건수 143건에 대한 재해자가 180명이 발생하였으며, 그 중 승객용 승강기는 전체 재해의 약 42.6%를 차지하고, 180명의 재해자 중에서 중상 이상의 재해자가 약 80.1%를 차지하고 있다.(중략)

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The Effect of Processing Variables on Structural Changes and Optical Properties of $SiO_2-TiO_2$ Sol-Gel Derived Films

  • Hwang, Jin Myeong;Im, Seong Su
    • Bulletin of the Korean Chemical Society
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    • v.21 no.12
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    • pp.1181-1186
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    • 2000
  • The structural evolution during the thermal treatment of $70SiO_2-3OTiO_2(mole%)$ sol-gel derived powders and films was investigated by FT-IR, Raman and XPS, and XRD. From these results, the $TiO_2-rich$ regions involving $Ti^{4+}$ ions in octahedral coordination were confirmed to be amorphous at $600^{\circ}C$. However, Raman spectra along with XRD patterns indicated that at high temperature (above $700^{\circ}C)$, the amorphous $TiO_2was$ segregating to form anatase crystal. Also, the effect of experimental variables such as thermal treatment, heating rate and exposure to water vapor on structural changes, refractive index and thickness of the film coated on sodalime-silicate glass were investigated.

Calculation on Surface Electronic State of $TiO_2$ Electrode (TiO2 전극 표면의 전자상태 계산)

  • Lee, Dong-Yoon;Lee, Won-Jae;Song, Jae-Sung
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2003.07a
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    • pp.259-262
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    • 2003
  • The surface electronic state of rutile $TiO_2$, which is an oxide semiconductor and has a wide band gap of 3.1 $\sim$ 3.5 eV, was calculated by DV-$X_{\alpha}$ method, which is a sort of the first principle molecular orbital method and uses Hartre-Fock-Slater approximation. The $[Ti_{15}O_{56}]^{-52}$ cluster model was used for the calculation of bulk state and the $[OTi_{11}O_{34}]^{-24}$ model for the surface state calculation. After calculations, the energy level diagrams and the deformation electron density distribution map were compared in both models. As results, it was identified that the surface energy levels are found between the valence and conduction band of bulk $TiO_2$ on the surface area. The energy values of these surface-induced levels are lower than conduction band of bulk $TiO_2$ by 0.1 $\sim$ 1 eV. From this fact, it is expected that the surface energy levels act as donar levels in n-type semiconductor.

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Orienting the superficial inferior epigastric artery (SIEA) pedicle in a stacked SIEA-deep inferior epigastric perforator free flap configuration for unilateral tertiary breast reconstruction

  • Yu, Ya-han;Ghorra, Dina;Bojanic, Christine;Aria, Oti N.;MacLennan, Louise;Malata, Charles M.
    • Archives of Plastic Surgery
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    • v.47 no.5
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    • pp.473-477
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    • 2020
  • Superficial inferior epigastric artery (SIEA) flaps represent a useful option in autologous breast reconstruction. However, the short-fixed pedicle can limit flap inset options. We present a challenging flap inset successfully addressed by de-epithelialization, turnover, and counterintuitive rotation. A 47-year-old woman underwent left tertiary breast reconstruction with stacked free flaps using right deep inferior epigastric perforator and left SIEA vessels. Antegrade and retrograde anastomoses to the internal mammary (IM) vessels were preferred; additionally, the thoracodorsal vessels were unavailable due to previous latissimus dorsi breast reconstruction. Optimal shaping required repositioning of the lateral ends of the flaps superiorly, which would position the ipsilateral SIEA hemi-flap pedicle lateral to and out of reach of the IM vessels. This problem was overcome by turning the SIEA flap on its long axis, allowing the pedicle to sit medially with the lateral end of the flap positioned superiorly. The de-epithelialized SIEA flap dermis was in direct contact with the chest wall, enabling its fixation. This method of flap inset provides a valuable solution for medializing the SIEA pedicle while maintaining an aesthetically satisfactory orientation. This technique could be used in ipsilateral SIEA flap breast reconstructions that do not require a skin paddle, as with stacked flaps or following nipple-sparing mastectomy.