• 제목/요약/키워드: phase analysis

검색결과 11,773건 처리시간 0.037초

시효된 수퍼 2상 스테인리스강의 피로균열 진전시 발생하는 음향방출신호의 시간-주파수 분석 (Time-Frequency Analysis of AE Signals at Fatigue Crack Propagation of Aged Super Duplex Stainless Steels)

  • 남기우;이상기;도재윤;강창룡
    • 한국해양공학회:학술대회논문집
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    • 한국해양공학회 2000년도 추계학술대회 논문집
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    • pp.20-25
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    • 2000
  • lh deleterious Cr, Mo rich -$\sigma$phase is a hard embrittling precipitate, which forms between MU)-900 $^{\circ}C$, often associated with a reduction in both impact properties and corrosion reshame. On this study, After aging at MU) "C, fatigue crack propagation induced by a phase precipitation was evaluated and time-frequency analysis of acoustic emission was conducted It was possible to find fracture mechanism by a phase precipitation due to time-frequency anulysis of acoustic emission signals.nals.

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The effects of repetitive firing processes on the optical, thermal, and phase formation changes of zirconia

  • Ozdogan, Alper;Ozdemir, Hatice
    • The Journal of Advanced Prosthodontics
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    • 제12권1호
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    • pp.9-14
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    • 2020
  • PURPOSE. The aim of this study was to investigate the effect of different numbers of heat treatments applied to superstructure porcelain on optical, thermal, and phase formation properties of zirconia. MATERIALS AND METHODS. Forty zirconia specimens were prepared in the form of rectangular prism. Specimens were divided into four groups (n = 10) according to the number of firing at heating values of porcelain. Color differences and translucency parameter were measured, and X-ray diffraction (XRD) analysis and differential scanning calorimetry (DSC) were performed. Data were analyzed with analysis of variance (ANOVA). RESULTS. There were no statistically significant differences in ∆E, TP, L, a, and b value changes of the zirconia specimens as a result of repetitive firing processes (P>.05). CONCLUSION. Although additional firing processes up to 4 increase peak density in thermal analysis, additional firing processes up to 4 times can be applied safely as they do not result in a change in color and phase character of zircon frameworks.

초고속 OCT응용을 위한 위상변조 광지연단 (Phase Modulation Optical Delay Line for Ultrafast OCT Application)

  • 황대석;이영우
    • 한국정보통신학회논문지
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    • 제9권4호
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    • pp.861-864
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    • 2005
  • 광위상변조기를 이용하여 OCT용 초고속 광지연단을 설계하고 수치해석을 수행하였다. 수치해석은 electro-optic 위상 변조기에 1310nm, 10ps의 펄스폭을 갖는 레이저 광원을 적용하여 수행하였다. 수치해석결과로 500MHz의 변조 주파수일때 19ps의 시간 지연을 얻었으며, 이는 기존의 기계적 검출 방식(수십kHz)의 OCT장치에 비해 1000배이상 빠른 검출이 가능할 것으로 예상된다.

유체로 연성된 다공 직사각평판의 실험적 모드 해석 (Experimental Modal Analysis of Perforated Rectangular Plates Coupled with Fluid)

  • 유계형;이명규;정경훈;이성철
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2002년도 추계학술대회 논문집
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    • pp.900-903
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    • 2002
  • This study dealt with the experimental modal analysis of the perforated rectangular plate coupled with fluid. The natural frequencies of the perforated plate and solid plate in air were obtained by the analytical method based on the relation between the reference kinetic and maximum potential energy and compared with the experimental results. Good agreement between the results was found for the natural frequencies of the perforated plate in air. It was empirically found the natural frequencies of the perforated plate coupled with fluid. The transverse vibration modes, in-phase and out-of-phase, were observed alternately in the fluid-coupled system. Additionally, the effect of distance between perforated plate and solid plate on the fluid-coupled natural frequency was investigated.

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순간압력강하치의 통계적 해석을 통한 경사관내 2상유동양식의 판별 (Identification of Two-Phase Flow Patterns in a Inclined Duct Based upon a Statistical Analysis of Instantaneous Pressure Drop)

  • 이상천;이정표;김중엽
    • 대한설비공학회지:설비저널
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    • 제17권5호
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    • pp.590-597
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    • 1988
  • Characteristics of flow regime transitions in inclined upwards gas-liquid two-phase flow have been investigated based upon a statistical analysis of instantaneous pressure drop curves through an orifice. The probability density functions of the curves indicate distinct patterns depending upon two-phase flow regime, which are very similar to those of horizontal two-phase. The dimensionless intensity of fluctuations of the pressure drops sharply change as the flow transitions such as plug-slug, pseudo slug-slug and annular-slug take place. The effects of inclination angle on the flow regime transitions have been also investigated. The results show that the method to identify the flow pattern based upon the statistical analysis of instantaneous pressure drops is suitable for inclined flow as well as horizontal flow.

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Spirituality: Concept Analysis Based on Hybrid Model

  • Oh Pok Ja;Kang Kyung Ah
    • 대한간호학회지
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    • 제35권4호
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    • pp.709-720
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    • 2005
  • Purpose. The purpose of this study was to obtain a clearer understanding of spirituality and examine the process of spirituality through defining the meaning and attributes of spirituality. Method. Concept analysis was done in the three phases, theoretical phase, fieldwork phase, and analytical phase suggested in the Hybrid Model. Five people participated in the fieldwork phase. Results. Spirituality is activated through self-awareness which occurs as spirit being activated through self-introspection, and through restoration of the relationship with Supreme Being. This interconnectedness with Supreme Being has an absolute impact on one's harmonious interconnectedness with self and neighbors, thus leads all the critical attributes of spirituality to be revealed. The core energy of this harmonious inter-connectedness is love. When activated, it has a great impact on an individual as integrative energy, leads one to go beyond everyday experience as well as to have new perspectives, and to live a satisfactory life in every aspect. Conclusion. The results of this study suggest that promotion of connectedness is the most important element in spiritual nursing interventions. The results can also be used effectively in developing spirituality assessment scales and theory.

2상 전동기 변환을 이용한 단상 영구자석형 Line-Start 모터의 정상특성해석 (Steady State Characteristic Analysis of Single-Phase Permanent Magnet Type Line-Start Motor Using 2-Phase Motor Transformations)

  • 이선권;강규홍;홍정표;김규탁
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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    • pp.119-121
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    • 2001
  • This paper presents steady state analysis of single-phase line-start motor. 2-phase motor transformation is performed to consider the different specifications between main and auxiliary windings. The symmetrical coordinates transformation is applied to solve the unbalanced magnetic field. The validity of analysis method is verified by comparing to experiments.

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불연속 전류모드에서의 다상 교호 강압컨버터의 정상상태 해석 및 모델링 (Modeling and Steady-state Analysis of the Multi-Phase Interleaved Buck converter in Discontinuous Inductor Current Mode)

  • 장성동;장은승;정세교;신휘범;이현우
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 2004년도 춘계학술대회 논문집
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    • pp.506-510
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    • 2004
  • A multi-phase interleaved buck converter is used to reduce current ripples and filter size of a power supply. This paper addresses the modelling and steady-state analysis of the multi-phase interleaved buck converter operated in discontinuous inductor current mode. The model is derived using an averaging technique in steady state. The do voltage ratio and the range of the discontinuous inductor current mode(DICM) and the continuous output current mode(COCM) are derived from the averaged state-space model. In addition, the efficiency is investigated according to the number of phase.

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AN EFFECT ANLYSIS OF RISK FACTORS FOR BUILD TRANSFER LEASE PROJECTS

  • Yang-Woo Lee;Soo-Yong Kim; Jung-Man Jung;Dae-Young Kim
    • 국제학술발표논문집
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    • The 2th International Conference on Construction Engineering and Project Management
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    • pp.498-508
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    • 2007
  • The Build-Transfer-Lease (BTL) projects have rapidly increased under the Government support during recent years. This paper presents the risk analysis of factors affecting BTL projects in the initial phase. This study resulted in 10 significant risk factors influencing on each phase of BTL projects and then factors were grouped into each phase. The sensitivity analysis was also performed to identify risk factors with more significant influence on BTL projects. The results may useful to practitioners in order to cope with risks in initial phase of BTL projects. The paper resulted in the distribution of risks to project parties, thus it can be used as standards for risk assignment to competent authorities and private enterprises of BTL projects.

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Deciphering Key Genes of Proliferative and Secretory Phase Using Integrated Transcriptomics and Network Analysis

  • Payal Gupta;Shriya Dube;Payal Priyadarshini;Shanvi Singh;Anasuya Pravallika R;Vijay Lakshmi Srivastava;Abhishek Sengupta;Priyanka Narad
    • 한국미생물·생명공학회지
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    • 제51권3호
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    • pp.317-324
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    • 2023
  • Endometrium receptivity is a complex mechanism of intricate pathways that lead to the shift from the proliferative to the secretory phase. Our goal was to identify high-ranking differentially expressed genes and study the pathways associated with the phenomenon. Raw data were retrieved from six GEO datasets and 705 DEGs were identified through robust ranking aggregation after the integration of five datasets. 20 key genes were identified that were further re-validated in an additional dataset. Supporting evidence through the experimental references confirms them as major biomarkers of the shift from the proliferative to the secretory phase.