• Title/Summary/Keyword: the in-plane flow

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Magnetic Anisotropy and Tectonic Stress Field of Tertiary Rocks in Pohang-Ulsan area, Korea (포항이남 제3기분지암석의 자기 비등방성과 지구조적 응력장)

  • Kim, In-Soo
    • Economic and Environmental Geology
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    • v.23 no.1
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    • pp.59-71
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    • 1990
  • Magnetic anisotropy of a total of 213 independently oriented Tertiary rock samples from Pohang-Ulsan area has been studied. The sampled strata comprise basalts, tuffs and black shale, and range in age from Eocene to Miocene. The previous palaeomagnetic studies indicate that their magnetic carrier minerals are titanomagnetites. Among 23 sampled sites, 11 sites were found to preserve magnetic load foliation parallel to the bedding plane caused by the Iithostatic load of the overlying strata. Other 4 sites showed magnetic lineation indicating the flow direction of lava and tuffs. The remaining 8 sites revealed the magnetic tectonic foliation nearly vertical to the bedding plane. This magnetic foliation is interpreted to be generated by tectonic compression which acted nearly horizontally during the solidification stage of the strata. The compression directions deduced from the tectonic foliation of the 8 sites can be grouped into internally very consistent two group: a N-S trending one and the other WNW-ESE trending one. It is interpreted that the former N-S compression was associated with the N-S spreading of the East Sea(Sea of Japan) and the dextral strike-slip movement of the Yangsan-Ulsan fault system. The latter WNW-ESE compression is interpreted to represent the folding and reverse faulting activity in the Korean and Tsushima straits during middle/late Miocene times.

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Modeling of Fine Sediment Transport under Multiple Breakwaters of Surface-Piercing Type

  • Lee, J. L.;Oh, M. R.
    • Proceedings of the Korea Water Resources Association Conference
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    • 2004.05b
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    • pp.557-562
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    • 2004
  • A surface-piercing barrier model is presented for understanding morphological development in the sheltered region and investigating the main factors causing the severe accumulation. Surface-piercing structures like vertical barriers, surface docks and floating breakwaters are recently favored from the point of view of a marine scenario since they do not in general partition the natural sea. The numerical solutions are compared with experimental data on wave profiles and morphological change rates within a rectangular harbor of a constant depth protected by surface-piercing thin breakwaters as a simplified problem. Our numerical study involves several modules: 1) wave dynamics analyzed by a plane-wave approximation, 2) suspended sediment transport combined with sediment erosion-deposition model, and 3) concurrent morphological changes. Scattering waves are solved by using a plane wave method without inclusion of evanescent modes. Evanescent modes are only considered in predicting the reflection ratio against the vertical barrier and energy losses due to vortex shedding from the lower edge of plate are taken into account. A new relationship to relate the near-bed concentration to the depth-mean concentration is presented by analyzing the vertical structure of concentration. The numerical solutions were also compared with experimental data on morphological changes within a rectangular harbor of constant water depth. Through the numerical experiments, the vortex-induced flow appears to be not ignorable in predicting the morphological changes although the immersion depth of a plate is not deep.

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A Study on the Clinical Use of 7-zone-diagnostic System(1) Centering around VEGA-DFM 722 and ABR-2000- (7구역진단기의 임상응용에 대한 고찰(1) -VEGA-DFM 722 및 ABR-2000 중심으로-)

  • Song, Beom-Yong
    • Journal of Acupuncture Research
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    • v.23 no.3
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    • pp.231-239
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    • 2006
  • Functional medicine is a system which utilizes certain investigative and treatment methods that are primarily oriented toward the recognition of functional disorder. Functional disorders take place on an energetic plane. This plane is not capturable using our regular investigatory techniques, such as X -ray. ultrasound, computer tomography and laboratory analyses. The 7-zone-diagnostic system(VEGA-DFM 722 and ABR-2000, etc) is a diagnostic device Which applies pulse signals to predetermined bodily locations. Applying alternating positive and negative stress to tissues with positive and negative pulses first manifests itself as negative and positive wave forms. The skin has many functions as an organ. It is the organism's interlace with the outsider world. Hence, the manner in which the skin reacts to external stimuli reflects the current state of the organism(as meridian systems). This system make a diagnosis of functional disorder or some typical organic diseases include stress of the mind or the body, and the energetic situation, reserves. We are known a disorder or disease throw the result chart. This result chart contain disorder flow wave forms and some valuable diagnostic hints (letters ; S, OM, RA, etc). In spite of this 7-zone-diagnostic system that is applied plentifully in the clinical application, there is not a statistics which is suitable. Therefor we must carry out many various research in the future.

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Defect Detection of Wall Thinned Straight Pipe using Shearography and Lock-in Infrared Thermography (전단간섭계와 적외선열화상을 이용한 감육 직관의 결함검출)

  • Kim, Kyeong-Suk;Jung, Hyun-Chul;Chang, Ho-Seob;Kim, Ha-Sig;La, Sung-Won
    • Journal of the Korean Society for Precision Engineering
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    • v.26 no.11
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    • pp.55-61
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    • 2009
  • The wall thinning defect of nuclear power pipe is mainly occurred by the affect of the flow accelerated corrosion (FAC) of fluid. This type of defect becomes the cause of damage or destruction of in carbon steel pipes. Therefore, it is very important to measure defect which is existed not only on the welding part but also on the whole field of pipe. This study use dual-beam Shearography, which can measure the out-of-plane deformation and the in-plane deformation by using another illuminated laser beam and simple image processing technique. And this study proposes Infrared thermography, which is a two-dimensional non-contact nondestructive evaluation that can detect internal defects from the thermal distribution by the inspection of infrared light radiated from the object surface. In this paper, defect of nuclear power pipe were, measured using dual-beam shearography and infrared thermography, quantitatively evaluated by the analysis of phase map and thermal image pattern.

Integrity Evaluation of Thinned Elbow Based on TES Plastic Load (TES 소성하중 기준의 감육엘보 기기건전성 평가)

  • Lee, Sung-Ho;Park, Chi-Yong;Lee, Jeong-Keun;Park, Jai-Hak
    • Proceedings of the KSME Conference
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    • 2008.11a
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    • pp.281-286
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    • 2008
  • Wall thinning defect due to flow accelerated corrosion is one of major aging phenomena in most power plant industries, and it results in reducing load carrying capacity of the piping systems. A failure testing system was set up for real scale elbows containing various simulated wall thinning defects, and monotonic in-plane bending tests were performed under internal pressure to find out the failure behavior of thinned elbows. Various finite element models were generated and analysed to figure out and simulate the behavior for other thinning shapes and loading conditions. This paper presents the decreasing trends of load carrying capacity according to the thinning dimensions which were revealed from the investigation of finite element analysis results. A mechanical integrity evaluation model for thinned elbows was proposed, also. This model can be used to calculate the TES plastic load of thinned elbows for general internal pressure, thinning location, and in-plane bending direction.

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A Study of Teachers' Pedagogical Content Knowledge about Area of Plane Figure (평면도형의 넓이 지도에 대한 교사의 PCK 분석)

  • Park, Sun Young;Kang, Wan
    • Journal of Educational Research in Mathematics
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    • v.22 no.4
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    • pp.495-515
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    • 2012
  • This study is to diversely analyze teachers' Pedagogical Content Knowledge (PCK) regarding to the area of plane figures and discuss the consideration for the materialization of the effective class in learning the area of plane figures by identifying the improvements based on problems indicated in PCK. The subjects of inquiry are what the problems with teachers' PCK regarding to the area of plane figures are and how they can be improved. In which is the first domain of PCK, teachers need to fully understand the concept of the area and the properties and classification of the area and length, recognized the sequence structure as a subject of guidance and improve the direction which naturally connects the flow of measurement by using random units in guidance of the area. In which is the second domain of PCK, teachers need to establish understanding of the concept for the area and understanding of a formula as a subject matter object and improve the activity, discovery and research oriented class for students as a guidance method by escaping from teacher oriented expository class and calculation oriented repetitive learning. They also need to avoid the biased evaluation of using a formula and evenly evaluate whether students understand the concept of the area as a performance evaluation method. In which is the third domain of PCK, teachers need to fully understand the concept of the area rather than explanation oriented correction and fundamentally teach students about errors by suggesting the activity to explore the properties of the area and length. They also need to plan a method to reflect student's affective aspects besides a compliment and encouragement and apply this method to the class. In which is the fourth domain of PCK, teachers need to increase the use of random units by having an independent consciousness about textbooks and supplementing the activity of textbooks and restructure textbooks by suggesting problematic situations in a real life and teaching the sequence structure. Also, class groups will need to be divided into an entire group, individual group, partner group and normal group.

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Signal Level Analysis of a Camera System for Satellite Application

  • Kong, Jong-Pil;Kim, Bo-Gwan
    • Proceedings of the KSRS Conference
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    • 2008.10a
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    • pp.220-223
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    • 2008
  • A camera system for the satellite application performs the mission of observation by measuring radiated light energy from the target on the earth. As a development stage of the system, the signal level analysis by estimating the number of electron collected in a pixel of an applied CCD is a basic tool for the performance analysis like SNR as well as the data path design of focal plane electronic. In this paper, two methods are presented for the calculation of the number of electrons for signal level analysis. One method is a quantitative assessment based on the CCD characteristics and design parameters of optical module of the system itself in which optical module works for concentrating the light energy onto the focal plane where CCD is located to convert light energy into electrical signal. The other method compares the design\ parameters of the system such as quantum efficiency, focal length and the aperture size of the optics in comparison with existing camera system in orbit. By this way, relative count of electrons to the existing camera system is estimated. The number of electrons, as signal level of the camera system, calculated by described methods is used to design input circuits of AD converter for interfacing the image signal coming from the CCD module in the focal plane electronics. This number is also used for the analysis of the signal level of the CCD output which is critical parameter to design data path between CCD and A/D converter. The FPE(Focal Plane Electronics) designer should decide whether the dividing-circuit is necessary or not between them from the analysis. If it is necessary, the optimized dividing factor of the level should be implemented. This paper describes the analysis of the electron count of a camera system for a satellite application and then of the signal level for the interface design between CCD and A/D converter using two methods. One is a quantitative assessment based on the design parameters of the camera system, the other method compares the design parameters in comparison with those of the existing camera system in orbit for relative counting of the electrons and the signal level estimation. Chapter 2 describes the radiometry of the camera system of a satellite application to show equations for electron counting, Chapter 3 describes a camera system briefly to explain the data flow of imagery information from CCD and Chapter 4 explains the two methods for the analysis of the number of electrons and the signal level. Then conclusion is made in chapter 5.

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The Structure Integrity Assessment of the Wall Thinned Elbow Considering In/Out-Plane Bending (열림·닫힘 방향 하중이 고려된 두께 감소된 엘보우의 건전성평가)

  • Jang, Ungburm;Shin, Kyuin;Lee, Sungho;Kuan, Changhee
    • Journal of the Society of Disaster Information
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    • v.12 no.1
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    • pp.1-9
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    • 2016
  • Local wall thinning elbow due to the water flow is one of the main degradation phenomenon in carbon steel pipe of plant system. The API579 code of FFS (fitness for service) used in the chemical plant gives a guideline to protect local wall thin problem in a straight pipe, but it does not include an elbow. In this study, the locally wall thinned elbow, which is considered an extrados or intrados wall thinned elbow, was carried out considering in-plane or out-plane bending using FEM (finite element method) analysis, and some of results were also compared with the experimental data. The results could give the structure integrity assessment to protect the local wall thinned elbow.

Digital Particle Holographic System for Flow-Field Measurements (유동장 계측을 위한 디지털 입자 홀로그래피 시스템)

  • Yan, Yang;Kang, Bo-Seon
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.34 no.3
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    • pp.309-316
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    • 2010
  • In this study, a digital particle holographic system and its application to channel-flow measurements were investigated. A double-exposure hologram recording system that is capable of recording digital holograms in a short time interval was developed. A correlation coefficient method was used to determine the focal plane of particles. The Wiener filter was used to remove noises and improve image quality. Two-threshold and image segmentation methods were used for binary image transformation. The cross-correlation method was used for particle pairing. The developed system was employed to study channel flow fields, and the axial velocities of channel flow were measured. The measurement errors are acceptable, and this proves the feasibility of using the digital particle holographic system as a good tool for flow-field measurements.

3-D Velocity Fields Measurements of Propeller Wake Using a Stereoscopic PIV (Stereoscopic PIV기법을 이용한 프로펠러 후류의 3차원 속도장 측정)

  • Paik Bu-Geun;Lee Sang-Joon
    • Proceedings of the KSME Conference
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    • 2002.08a
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    • pp.185-188
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    • 2002
  • The objective of present paper is to apply a stereoscopic PIV(Particle Image Velocimetry) techiique for measuring the 3 dimensional flow structure of turbulent wake behind a marine propeller with 5 blades. It is essential to measure 3-components velocity fields for the investigation of complicated near-wake behind the propeller. The out-of-plane velocity component was measured using the particle images captured by two CCD cameras in the angular displacement configuration.400 instantaneous velocity fields were measured for each of few different blade phases of $0^{\circ},\;18^{\circ},\;36^{\circ}\;and\;54^{\circ}$. They were ensemble averaged to investigate the spatial evolution of the propeller wake in the region ranged from the trailing edge to the region of one propeller diameter(D) downstream. The phase-averaged velocity fields show the viscous wake formed by the boundary layers developed along the blade surfaces. Tip vortices were formed periodically and the slipstream contraction occurs in the near-wake region. The out-of-plane velocity component has large values at the tip and trailing votices. With going downstream, the axial turbulence intensity and the strength of tip vortices were decreased due to the visous dissipation, turbulence diffusion and blade-to-blade interaction. The blade wake traveling at higher speed with respect to the tip vortex overtakes and interacts with tip vortices formed from the previous blade. Tip vortices are separated from the wake and show oscillating trajectory

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