• 제목/요약/키워드: Physical Mode

검색결과 679건 처리시간 0.029초

혼합모드 하중하에서 제하 컴플라이언스법에 의한 파괴 인성 측정 (Measurement of Fracture Toughness JC Under Mixed Mode Loading Using Unloading Compliance Method)

  • 심재룡;이영숙;김도형;범현규;강기추
    • 대한기계학회논문집A
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    • 제26권1호
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    • pp.113-120
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    • 2002
  • Experimental procedure to measure fracture toughness (J$_{c}$) under mixed mode loading using CTS(Compact Tension-Shear) specimens is described. It\`s loading angle ranges from 0$^{\circ}$ to 45$^{\circ}$ with interval of 157. The general outline of experimental procedure is similar to that of ASTM E8l3-89 fur mode I fracture. Equations fur determining J-integral is quoted from the authors' previous works. The relation between unloading compliance and physical crack size was calibrated. As an example, fracture toughness of aluminum alloy 2024p-7361 was measured and some reasonable results of J$_{c}$ with various loading angles were obtained.

SILO 구조의 제작 방법과 소자 분리 특성 (Fabrication and characterization of SILO isolation structure)

  • 최수한;장택용;김병렬
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1988년도 전기.전자공학 학술대회 논문집
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    • pp.328-331
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    • 1988
  • Sealed Interface Local Oxidation (SILO) technology has been investigated using a nitride/oxide/nitride three-layered sandwich structure. P-type silicon substrate was either nitrided by rapid thermal processing, or silicon nitride was deposited by LPCVD method. A three-layered sandwich structure was patterned either by reactive ion etch (RIE) mode or by plasma mode. Sacrificial oxidation conditions were also varied. Physical characterization such as cross-section analysis of field oxide, and electrical characterization such as gate oxide integrity, junction leakage and transistor behavior were carried out. It was found that bird's beak was nearly zero or below 0.1um, and the junction leakages in plasma mode were low compared to devices of the same geometry patterned in RIE mode, and gate oxide integrity and transistor behavior were comparable. Conclusively, SILO process is compatible with conventional local oxidation process.

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물리치료사의 자립개원 (Independent Clinic Open of Physical Therapist)

  • 송주영;김형남;조귀순
    • The Journal of Korean Physical Therapy
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    • 제8권1호
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    • pp.81-89
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    • 1996
  • This study is to make legal suggestions concerning the legal status of the physical therapists and the their clinics io Korea. This study compares the legal status of the physical therapists with that of the optical and dental technicians, and reviews the current system of the American physical therapeutic clinic. 1. Under the supervision of the doctor or dentist' in Article 1 of Law concerning the Medical Technician should be deleted or changed into 'by the request of the doctor or dentist'. A new independent law should be mode only fer the physical therapist from the general law that stipulates the legal status of other similar medical technicians. 3. The legal status of the physical therapeutic clinic should be stipulated in the regulations for the application of the law as that of the dental technician does. The modification of the medical services, the medical expences, waiting time, the easy access to the clinic of farmers, fishermen, urban laborers, and handicapped people, and the development of the area of the physical therapy.

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제트 엔진 산란 해석을 위한 하이브리드 IPO-MoM 기법 (A Hybrid IPO-MoM Technique for Wave Scattering Analysis of Jet Engine)

  • 임호;최승호;명로훈
    • 한국전자파학회논문지
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    • 제20권8호
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    • pp.791-796
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    • 2009
  • 전기적으로 크면서 동시에 복잡한 구조인 제트 엔진의 산란 해석을 위해 하이브리드 IPO-MoM(Iterative Physical Optics-Method of Moments) 기법을 제시하였다. 이 기법에서 IPO 기법은 전기적으로 부드럽게 변하는 inlet 영역을, MoM 기법은 회전축과 회전날개를 포함한 전기적으로 복잡하게 변하는 영역을 해석하였다. 각 기법의 장점을 융합하여 상대적으로 효율적이고 정확한 해석이 가능하였다. 수치 결과를 제시하고 기존 Mode-FDTD, 측정 결과와 비교하여 제시한 기법을 검증하였다.

Identification of nonlinear elastic structures using empirical mode decomposition and nonlinear normal modes

  • Poon, C.W.;Chang, C.C.
    • Smart Structures and Systems
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    • 제3권4호
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    • pp.423-437
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    • 2007
  • The empirical mode decomposition (EMD) method is well-known for its ability to decompose a multi-component signal into a set of intrinsic mode functions (IMFs). The method uses a sifting process in which local extrema of a signal are identified and followed by a spline fitting approximation for decomposition. This method provides an effective and robust approach for decomposing nonlinear and non-stationary signals. On the other hand, the IMF components do not automatically guarantee a well-defined physical meaning hence it is necessary to validate the IMF components carefully prior to any further processing and interpretation. In this paper, an attempt to use the EMD method to identify properties of nonlinear elastic multi-degree-of-freedom structures is explored. It is first shown that the IMF components of the displacement and velocity responses of a nonlinear elastic structure are numerically close to the nonlinear normal mode (NNM) responses obtained from two-dimensional invariant manifolds. The IMF components can then be used in the context of the NNM method to estimate the properties of the nonlinear elastic structure. A two-degree-of-freedom shear-beam building model is used as an example to illustrate the proposed technique. Numerical results show that combining the EMD and the NNM method provides a possible means for obtaining nonlinear properties in a structure.

비균일 전송선의 전자기적 결합, II:원통형 TEM 모드 해의 수정 (Electromagnetic Coupling to Nonuniform Transmission Lines, II:Correction to the Cylindrical TEM Mode Solution)

  • 홍성용;김세윤;라정웅
    • 전자공학회논문지A
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    • 제30A권2호
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    • pp.10-15
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    • 1993
  • The cylindrical TEM mode solution for electromagnetic coupling to an angled two-wire transmission line is corrected by imposing some physical constraints additionally. The validity of the correction process is assured by showing that the corrected solution approaches the numerical result for the equivalent model of cascaded piecewise uniform sections.

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부분구조합성법을 이용한 대형선박엔진의 진동분석 (Vibration Analysis for a Huge Marine Engine using a Substructure Synthesis Method)

  • 이재환;정종하;김재실;박형호
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2001년도 춘계학술대회논문집B
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    • pp.651-657
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    • 2001
  • This article explains the theory of multiple mode/physical coordinate synthesis method in order to analyze the dynamic characteristics for an huge marine engine. The theory leads to make a simulation code. The natural frequencies obtained from the simulation code is compared to those from a commercial analysis software, ANSYS. The simulation code is well reviewed.

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두부 CT 검사 시 검사 모드에 따른 화질 및 선량평가 (Image Quality and Dose Assessment According to Examination Mode during Head CT Examination)

  • 강헌효;최우전;김동현
    • 한국방사선학회논문지
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    • 제15권4호
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    • pp.437-444
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    • 2021
  • 두경부 CT 검사시 팬텀을 이용하여 Helical mode, High Pitch Mode, Volume Axial Mode 사용하여 획득한 CT 영상으로부터 환자의 피폭선량과 각 영상의 화질을 비교 및 분석하여 Volume Axial Mode의 유용성을 평가해보고자 한다. 두경부 CT 검사 시 각 mode에 따른 70 kVp, 80 kVp, 100 kVp 관전압에 따라 검사를 시행하였다. 사용 장비로는 GE사의 Revolution(GE Healthcare, Wisconsin USA) 모델과 iMED X-ray Phantom을 이용하였다. 검사 Mode에따른 kVp별로 얻어진 영상을 이용하여 팬텀의 피폭선량을 비교하였으며, 각 영상에 ROI를 설정해 신호대 잡음비와 대조도대 잡음비를 산출하여 영상의 화질을 비교하였다. Volume Axial Mode를 사용하여 검사하였을 때 팬텀의 피폭선량이 Helical에 비해 17.12% 낮게, High Pitch에 비해 5.35% 낮게 측정되었고, 신호대 잡음비와 대조도대 잡음비가 향상되었다. Volume Axial Mode는 고속 회전 스캐너를 이용하여 테이블의 이동이 없이 조사시간을 줄이고, High Pitch Mode와 Helical Mode를 사용했을 때 보다 팬텀의 0.28초의 단시간에 영상을 획득하여 피폭선량이 감소하고 영상의 화질 또한 향상되는 유용한 검사라 할 수 있다. 또, 몸이 불편한 환자의 촬영이나 긴급환자의 CT 촬영에 있어서 Volume Axial Mode의 빠른 검사시간은 최대의 장점이라고 볼 수 있다.

분만방법 유형이 골반바닥근육 기능에 미치는 영향 (Effects of Pelvic Floor Muscle Function on Mode of Delivery)

  • 권유정;이현옥
    • PNF and Movement
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    • 제15권3호
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    • pp.373-380
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    • 2017
  • Purpose: The purpose of this study was to investigate of the effects of the mode of delivery on pelvic floor muscle function by examining bladder base movement and urinary incontinence. Methods: This study was conducted on 100 females who had delivered in the previous 3-8 months. There were 2 groups: 56 vaginal deliveries and 44 cesarean section deliveries. Prior to the study, a survey was conducted on the subjects' general status, delivery mode, urinary incontinence, and physical activity. The groups could not be blinded due to scar tissue from the operations. The function of the pelvic floor muscle was observed with the bladder base movement using transabdominal ultrasound during pelvic floor contraction. To objectify and measure the subjective symptoms of subjects suffering from urinary incontinence, an incontinence quality of life (I-QoL) test was administered. Statistical analysis of the data was performed using SPSS version 20.0. An independent t-test was used to assess the statistical significance of pelvic floor muscle function between the 2 groups after delivery. Results: The movement of the bladder base in the pelvic floor muscle function was decreased in the vaginal delivery group, but the difference was not significant. Urinary incontinence was significantly increased in the vaginal delivery group. Conclusion: The function of the pelvic floor muscles was better in the cesarean section group and the incidence of urinary incontinence was relatively low in this group. Therefore, vaginal delivery requires more efforts to restore the function of the pelvic floor muscles than cesarean delivery.