• Title/Summary/Keyword: Misfit

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Effects of Lattice Mismatch on Photoluminescence Efficiency of InGaAsP/InP Heterostructures (InGaAsP/InP이종접합구조의 격자부정합이 Photoluinescence효율에 미치는 영향)

  • Lee, Jong-Won
    • Korean Journal of Materials Research
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    • v.4 no.5
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    • pp.516-523
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    • 1994
  • The interfacial coherency of metal organic chemical vapor deposition grown InGaAsP/InP heterostructure wafers was examined and their influences on the optoelectronic properties were investigated in this study. (400) symmetric and (511) asymmetric reflections were employed to measure the lattice coherency. Existence of misfit dislocations was examined by x-ray topography and reverified by photoluminescence (PL) imaging. PI, measurements were performed, and higher PL intensity was obtained for elastically strained samples and lower intensity for plastically deformed samples. The highest PL intensity was obtained for the sample lattice matched at the growth temperature. PL full-width at half maximum (FWHM) was found to depend on the degree of lattice mismatch. A correlatior between x-ray FWHM and PL intensity was empirically established. The results presented demonstrate that the interfacial coherency is of primary significance in affecting the optoelectronic properties through elastic strain and plastic deformation.

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Comparison the fit of three-unit metal framework fabricated by wax milling method and digital light projection method (왁스 밀링 방법 및 디지털 광 프로젝션 방법으로 제작된 3본 금속 구조물의 적합도 비교)

  • Lee, Jung-Hwan;Ahn, Jae-Seok
    • Journal of Technologic Dentistry
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    • v.41 no.1
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    • pp.9-19
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    • 2019
  • Purpose: This study was conducted to comparative evaluate the marginal and internal gap of three-unit metal frameworks(Co-Cr) fabricated by wax milling method and digital light projection method of CAD/CAM systems. Methods: All the specimens were fabricated by three different fabrication methods: conventional wax up with casting(CWC), milled wax block with casting(MWC), digital light projection with casting(DLPC) (n=10 each). The marginal and internal fits of specimens were examined using a replica technique. The light-body silicone thickness was measured at 8 reference points(each abutment: 16 measurements). All measurements were conducted by a stereomicroscope. Digital photo were taken at $150{\times}$ magnification and then analyzed using a measurement software. The Mann-Whitney test was used for analyzing the results. Results: Statistically significant differences were found between the fabrication methods(p<0.001). The mean(SD) is ${\mu}m$ for fabrication methods, the mean marginal fit were recorded respectively, CWC 63(38), MWC group 50(33), DLPC 103(54) and the mean internal fit CWC 96(47), MWC group 116(41), DLPC 138(66). Conclusion : The marginal and internal fit were statistically different according to the fabrication methods(p<0.001). In all fabrication methods, the greatest misfit was found the occlusal area of all specimens.

Application of Rasch Analysis to the Korean Berg Balance Scale (한국판 버그 균형척도 평가도구의 라쉬분석)

  • Lee, Jung-Ah;Yi, Chung-Hwi;Park, So-Yeon;Hwang, Su-Jin
    • Physical Therapy Korea
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    • v.13 no.3
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    • pp.49-56
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    • 2006
  • This study was designed to examine, using Rasch analysis, the rating scale performance of the Korean version of the Berg Balance Scale (BBS). The subjects were 95 elderly people at community dwelling. Subjects (19 men, 76 women) ranged in age from 65 to 91 years. Rasch analysis was then done by means of the Winsteps program to determine the validity and reliability of the Korean version of the BBS evaluation tools for elderly people. The results were as follows: Twenty-one elderly people were excluded for misfit persons. Three items were found to be misfits and the order of item difficulty of the remaining 11 items was arranged. Elderly people BBS ability is indicated by -.94~7.41 logit, and the transformation formula is score=(logit score+.94)/$(.94+7.41){\times}100$. This transformation formula can be applied to Korean elderly people for balance ability. In the order of difficulty of evaluation items, the most difficult item was "Standing on one foot" and the easiest item was "Standing to Sitting". In conclusion, the Korean version of BBS evaluation tool for the elderly people has been proved valid and will be useful in clinical practice and research in Korea.

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FIT OF FIXTURE/ABUTMENT/SCREW INTERFACES OF INTERNAL CONNECTION IMPLANT SYSTEM

  • Kim, Jin-Sup;Kim, Hee-Jung;Chung, Chae-Heon;Baek, Dae-Hwa
    • The Journal of Korean Academy of Prosthodontics
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    • v.43 no.3
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    • pp.338-351
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    • 2005
  • Statement of problem. Accurate fit between the implant components is important because the misfit of the implant components results in frequent screw loosening, irreversible screw fracture, plaque accumulation, poor soft tissue reaction, and destruction of osseointegration. Purpose. This study is to evaluate the machining accuracy and consistency of the implant fixture/ abutment/screw interfaces of the internal connection system by using a Stereoscopic Zoom microscope and FE-SEM(field emission scanning electron microscope) Materials and methods. The implant systems selected in this study were internal connection type implants from AVANA(Osstem^{\circledR}), Bioplant(Cowell-Medi^{\circledR}), Dio(DIO^{\circledR}), Neoplant(Neobiotech 􀋓), Implantium(Dentium􀋓)systems. Each group was acquired 2 fixtures at random. Two piece type abutment and one piece type abutment for use with each implant system were acquired. Screw were respectively used to hold a two piece type abutment to a implant fixture. The implant fixtures were perpendiculary mounted in acrylic resin block. Each two piece abutment was secured to the implant fixture by screw and one piece abutment also secured to the implant fixture. Abutment/fixture assembly were mounted in liquid unsaturated polyester. All samples were cross-sectioned with grinder-polisher unit. Finally all specimens were analysed the fit between implant fixture/abutment/screw interfaces Results and conclusions. 1. Implant fixture/abutment/screw connection interfaces of internal connection systems made in Korea were in good condition. 2. The results of the above study showed that materials and mechanical properties and quality of milling differed depending on their manufacturing companies.

Evaluation of Material Properties in Austenite Stainless Steel Sheet with Scanning Acoustic Microscopy (초음파현미경을 이용한 오스테나이트 스테인레스강의 재료특성 평가)

  • Park, Tae-Sung;Kasuga, Yukio;Park, Ik-Keun;Kim, Kyoung-Suk;Miyasaka, Chiaki
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.21 no.2
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    • pp.267-275
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    • 2012
  • Austenite stainless steel 304 has properties of high resistance to corrosion and temperature changes. Therefore, this material is widely used in various of industries. However, when the material is subjected to heating and cooling cycles the forming accuracy, for example, the right angle associated with a sharp bend such as corner is lost. This phenomenon is caused by the reversion of the deformation-induced martensite into austenite when the temperature in increased. This result in misfit of a structure or an assembly, and an increase in residual stress. Hence, it is important to understand this process. In this study, to evaluate the mechanical behavior of the deformation-induced martensite and reversed austenite, a scanning acoustic spectroscope including the capability of obtaining both phase and amplitude of the ultrasonic wave (i.e., the complex V(z) curve method) was used. Then, the velocities of the SAW propagating within the specimens made in different conditions were measured. The experimental differences of the SAW velocities obtained in this experiment were ranging from 2,750 m/s to 2,850 m/s, and the theoretical difference was 3.6% under the assumption that the SAW velocity was 2,800 m/s. The error became smaller as the martensite content was increased. Therefore, the SAW velocity may be a probe to estimate the marternsite content.

Determination of Weighting Factor in the Inverse Model for Estimating Surface Velocity from AVHRR/SST Data (AVHRR/SST로 부터 표층유속을 추정하기 위한 역행렬 모델에서 가중치의 설정)

  • Lee, Tae-Shin;Chung, Jong-Yul;Kang, Hyoun-Woo
    • 한국해양학회지
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    • v.30 no.6
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    • pp.543-549
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    • 1995
  • The inverse method has been used to estimate a surface velocity field from sequential AVHRR/SST data. In the model, equation system was composed of heat equation and horizontal divergence minimization and the velocity field contained in the advective term of the heat equation, which was linearized in grid system, was estimated. A constraint was the minimization of horizontal divergence with weighting factor and introduced to compensate the null space(Menke, 1984) of the velocity solutions for the heat equation. The experiments were carried out to set up the range of weighting factor and the matrix equation was solved by SVD(Singular Value Decomposion). In the experiment, the scales of horizontal temperature gradient and divergence of synthetic velocity field were approximated to those of real field. The neglected diffusive effect and the horizontal variation of heat flux in the heat equation were regarded as random temperature errors. According to the result of experiments, the minimum of relative error was more desirable than the minimum of misfit as the criteria of setting up the weighting factor and the error of estimated velocity field became small when the weighting factor was order of $10^{-1}$

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Crystal Structure and Magnetic Properties of $(LaS)_xCrS_2(x{\approx}1.20)$ ($(LaS)_xCrS_2(x{\approx}1.20)$의 결정구조와 자기적 특성)

  • Jo, Nam-Ung;Yu, Gwang-Su;Jeong, Hyeong-Jin
    • Korean Journal of Materials Research
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    • v.4 no.6
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    • pp.704-709
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    • 1994
  • The $(LaS)_xCrS_2(x \approx 1.20$) of the incommensurate misfit layer was systhesized from reactant mixture of$La_S_3$,Cr and S at 1273K. Powder X-ray diffration of $(LaS)_xCrS_2(x \approx 1.20$) was indexed as a complex structure consisted with a monoclinic LaS-sublattice, a triclinic $CrS_{2}$-sublattice and their superlattice. The temperature dependence of sublattice dimension was investigated by the X-ray diffraction analysis at low temperature. The magnetic susceptibility of $(LaS)_xCrS_2(x \approx 1.20$) was measured between 77K and room temperature using a Faraday balance method. $(LaS)_xCrS_2(x \approx 1.20$) was paramagnetic on a $\sigma$-H plot at room temperature. The observed effective magnetic moment( p dr) was in fair agreement with the value calculated by spin-only contribution for $Cr^{3+}$ and spin and orbital contribution for $La^{3+}$.

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A semiotic analysis of narrative structure in (<노다메 칸타빌레>의 내러티브 구조와 기호학적 분석)

  • Kwon, Jae-Woong;Choi, Se-Young
    • Cartoon and Animation Studies
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    • s.27
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    • pp.127-151
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    • 2012
  • Created by Tomoko Ninomiya, was serialized in Japan from July 2001 to November 2009 and collected in 23 volumes. It has become a cultural syndrome after it was transferred to other media. Giving an attention to this cultural syndrome, this study aims to analyze narrative structure by means of semiotics. This study tries to use 'modele actantiel' and 'carre semiotique' of Greimas in order to clarify not only the meaning structure but also the course of narrative revealed in . The meaning structure of shows a unique relationship of genius and training. Although Nodame, a main character of this Japanese manga, is a straggler in music school because she does not show any passion for learning, she is depicted as a music genius. An education method called as apprenticeship is represented as the mechanism to bring out misfits in music. Dealing with her long journey to be a professional musician, this manga suggests how Nodame can be developed from as a misfit to as a professional pianist through introducing diverse education methods. Revealing critical perspective on music education in real world, gives a chance to rethink the relationship between genius and education in music.

The effects of Peer Relationship and Dysfunctional Family on Life Adjustment in University (대학생의 교우관계, 역기능 가정이 대학생활적응에 미치는 영향)

  • Jang, Sung-Hwa;Chun, Young-Hee;Ham, Seong-Soo
    • The Journal of the Korea Contents Association
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    • v.14 no.6
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    • pp.539-548
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    • 2014
  • The purpose of this study was to analyze the predictors of peer relationship and the dysfunctional family on life adjustment in university. The participants of study were 415 university students in Seoul province. A survey was carried out using convenient sampling, and correlation analysis and multiple regression were conducted. The results were summarized as follows: First, as for the peer relationship, dysfunctional family and life adjustment in university, all of the subvariables except for conflict, distrust and university of adaptation show significant correlations. Second, a multiple regression analysis showed that, in order of significance, conflict resolution, problem parents, recognition and attention variables significantly affected life adjustment in university. This has implications for the prevention of misfit university students, the related program development, and various policy establishments.

Applying Rasch Analysis for Validation of School Function Assessment (학교기능평가(School Function Assessment)도구의 구성타당도 검증을 위한 라쉬분석의 적용)

  • Park, Kyoung-Young
    • The Journal of the Korea Contents Association
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    • v.14 no.3
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    • pp.269-276
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    • 2014
  • The purpose of this study is to investigate validation of the School Function Assessment(SFA) for Korean Version using Rasch analysis. The subjects were recruited 98 students with disabilities in Seoul, Kyoung-Ki, Chung-cheung. The data were analysed using Rasch analysis to investigate unidimensionality and rating scale model. The 4 items out of SFA Part II were found to be misfts. The 18 items out of physical tasks, the 14 items out of cognitive/behavioral tasks in Part III were found to be misfit. All rating scale in SFA was appropriate. Further studies are needed to investigate validity and criterion cut-off score for many students with disabilities.