• Title/Summary/Keyword: Cross-sectional data

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A Cross-Sectional Study on the Association of Fiber Intake and Large Bowel Function (대장기능과 섬유질 섭취와의 상관성에 대한 단면적 조사연구 -서울지역 성인을 대상으로-)

  • 이상선
    • Journal of Nutrition and Health
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    • v.26 no.9
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    • pp.1085-1097
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    • 1993
  • Recently, as korean eating habits have been westernized, the incidence of large intestinal disease, which has been recognized as western diseases until now, has been increasing. This study was conducted to find the association of fiber intake and large bowel function. This was a cross-sectional survey, the data were obtained by self-administering questionnaire and study population was adults aged more than 18 years old in Seoul(N=1200). The response rate was 81.8%. The results were summarized as followed: 1) The factors associated with bowel function was sex, habits of defecation such as regularity and frequencies of defecation, fecal form, gastrointestinal diseases, psychological scores, self-assessment of physical status, exercise and alcohol drinking. 2) The association between the amount of fiber intake and bowel function was significant. This association was still significant, when the confounders such as disease of upper digestive system and alcohol drinking were controlled.

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Cross-Sectional and Longitudinal Relationships Between Aggression, Prosocial Behavior and Peer Relations (아동의 외현적, 관계적 공격성 및 친사회성과 또래관계와의 횡·종단적 관계)

  • Sim, Hee-Og
    • Korean Journal of Child Studies
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    • v.26 no.2
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    • pp.121-134
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    • 2005
  • Data were collected by peer nomination and sociometric nomination when children were in 4th grade and again two years later, Concurrent results of peer nominations were that prosocial children were more accepted while overtly/relationally aggressive children were more rejected by peers. Peer acceptance of males at Time 1 affected peer acceptance at Time 2. Peer rejection of females at Time 2 wasn't affected by overt aggression at Time 1. Cross-sectional results of social status were that rejected and controversial children showed higher levels of overt aggression than any other group. Popular children were most prosocial; rejected children were least prosocial. In the prospective view, aggressive males remained more rejected than any other group. Rejected children remained least prosocial.

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Laser Processing for Manufacturing Styrofoam Pattern (주물용 스티로폼 목형 제작을 위한 레이저 가공 공정 개발)

  • 강경호;김재도
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2001.04a
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    • pp.1085-1088
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    • 2001
  • The process of styrofoam pattern that has been used for material of press die pattern depends chiefly on handwork. Laser manufacturing system developed to increase precision and efficiency of process that is also able to convert the design easily. Applying the RP(rapid prototyping) concept reversely, the unnecessary part of section is vapored away by heat source of laser beam after converting 3-D CAD model into cross-sectional shape information. Laser beam is line-scanned in plane specimens to measure the depth and width of cut, surface roughness, cross-sectional shape as converting laser power, scanning speed, cutting gas pressure. With these basic data, plane surface, inclined surface, hole, outer contour trimming process is experimented and optimum condition are obtained. In plane and inclined surface experiments, 15W laser power and 50mm/s scanning speed make superior processing property and 30W, 10mm/s make processing efficiency increase in trimming process. With these results, simple patterns were manufactured and the possibility of applying laser manufacturing system to styrofoam pattern was convinced.

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Experimental Study on the Three Dimensional Unsteady Flow in a Counter Rotating Axial Flow Fan (엇회전식 축류팬의 3 차원 비정상 유동에 관한 실험적 연구)

  • Park, Hyun-Soo;Cho, Lee-Sang;Kang, Hyun-Koo;Cho, Jin-Soo
    • Proceedings of the KSME Conference
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    • 2003.11a
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    • pp.822-827
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    • 2003
  • Experiments were done for the three dimensional unsteady flow in a counter rotating axial flow fan under stable operating condition. Flow fields in a counter rotating axial flow fan were measured at cross-sectional planes of the upstream and downstream of each rotor. Cross sectional flow patterns were investigated through the acquired data by the $45^{\circ}$ inclined hot-wire. Flow characteristics such as tip vortex, secondary flow and tip leakage flow were confirmed through axial, radial and tangential velocity vector plot. Swirl velocity, which was generated by the front rotor, was recovered in the form of static pressure rise by the rear rotor except for hub and tip regions.

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Simulation of Shape Control in Cold Rolling Using Fuzzy Control (퍼지제어를 이용한 냉연공정 형상제어 시뮬레이션)

  • 정종엽;임용택;진철제;이해영
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.18 no.2
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    • pp.302-312
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    • 1994
  • In this study, a fuzzy theory is introduced to control the cross-sectional strip shape in cold rolling. A fuzzy controller is developed based on the production data and the operational knowledge. The cold rolled products are characterized into several types based on their irregularities. For each type of irregular strip shape, fuzzy controller calculates the changes of bender forces of work and intermediate rolls using fuzzy control algorithm. To simulate the continuous shape control, fuzzy controller is linked with emulator which is developed using neural network. The developed fuzzy controller and emulator simulate the cold rolling process until the irregularities converge to the tolerable range to produce unifrom cross-sectional strip shape. The results from this simulation are reasonable for various irregular strip shapes.

Electrical Impedance Tomography and Biomedical Applications

  • Woo, Eung-Je
    • 한국지구물리탐사학회:학술대회논문집
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    • 2007.06a
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    • pp.1-6
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    • 2007
  • Two impedance imaging systems of multi-frequency electrical impedance tomography (MFEIT) and magnetic resonance electrical impedance tomography (MREIT) are described. MFEIT utilizes boundary measurements of current-voltage data at multiple frequencies to reconstruct cross-sectional images of a complex conductivity distribution (${\sigma}+i{\omega}{\varepsilon}$) inside the human body. The inverse problem in MFEIT is ill-posed due to the nonlinearity and low sensitivity between the boundary measurement and the complex conductivity. In MFEIT, we therefore focus on time- and frequency-difference imaging with a low spatial resolution and high temporal resolution. Multi-frequency time- and frequency-difference images in the frequency range of 10 Hz to 500 kHz are presented. In MREIT, we use an MRI scanner to measure an internal distribution of induced magnetic flux density subject to an injection current. This internal information enables us to reconstruct cross-sectional images of an internal conductivity distribution with a high spatial resolution. Conductivity image of a postmortem canine brain is presented and it shows a clear contrast between gray and white matters. Clinical applications for imaging the brain, breast, thorax, abdomen, and others are briefly discussed.

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The Determinants of Future Bank Stock Returns in Eight Asian Countries

  • An, Jiyoun;Na, Sung-O
    • East Asian Economic Review
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    • v.18 no.3
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    • pp.253-276
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    • 2014
  • We examine which traditional asset pricing variables together with bank-specific accounting variables explain the cross-sectional variation of future bank stock returns, using a firm-level data of eight Asian countries. Our empirical evidence shows that exchange rate risk, firm size, the book-to-market ratio, and the net income ratio are important in explaining future bank stock returns during normal times. However, during the Global Financial Crisis period, different variables such as local market beta, illiquidity risk, equity ratio, and off-balance sheets ratio were statistically significant. Thus, researchers and policy practitioners should monitor these variables during normal times as well as during times of crisis.

Next Generation Fiber Length Measurement

  • Tiikkaja, Esa;Sopenlehto, Taina
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.32 no.5
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    • pp.54-59
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    • 2000
  • The next generation fibre size analyser has been developed in Kajaani based on over 15 years experience in fibre measurement. This new FiberLab-analyser can measure fibre length both along the fibre centre line and as projected. The cross-sectional measurements of fibre are in principle similar to the earlier version FiberLab. Measured data are generally displayed in distributions. Some new calculations have been added, for example the fibres cross sectional area and fibre volume index both available as distributions as well. The performance of the FiberLab measurement is verified against the manual microscopic testing. These tests show that the new image analysis-based measurement well matches with the manual methods.

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Experimental study of compression waves propagating into two-continuous tunnels (두 연속 터널을 전파하는 압축파의 실험적 연구)

  • Kim, Hui-Dong;Heo, Nam-Geon;Setoguchi, Toshiaki
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.21 no.10
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    • pp.1294-1302
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    • 1997
  • For the purpose of investigating the impulsive noise at the exit of high-speed railway tunnel and the pressure transients inside the tunnel, experiments were carried out using a shock tube with an open end. A great deal of experimental data were obtained and explored to analyze the peak pressures and maximum pressure gradients in the pressure waves. The effects of the distance and cross-sectional area ratio between two-continuous tunnels on the characteristics of the pressure waves were investigated. The peak pressure inside the second tunnel decreases for the distance and cross-sectional area ratio between two tunnels to increase. Also the peak pressure and maximum pressure gradient of the pressure wave inside the second tunnel increase as the maximum pressure gradient of initial compression wave increases.

A Study on the Shape of the Pattern Milled Using FIB (집속이온빔 연마에 의한 패턴의 형태에 관한 연구)

  • Jung, Won-Chae
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.27 no.11
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    • pp.679-685
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    • 2014
  • For the measurements of surface shape milled using FIB (focused ion beam), the silicon bulk, $Si_3N_4/Si$, and Al/Si samples are used and observed the shapes milled from different sputtering rates, incident angles of $Ga^+$ ions bombardment, beam current, and target material. These conditions also can be influenced the sputtering rate, raster image, and milled shape. The fundamental ion-solid interactions of FIB milling are discussed and explained using TRIM programs (SRIM, TC, and T-dyn). The damaged layers caused by bombarding of $Ga^+$ ions were observed on the surface of target materials. The simulated results were shown a little bit deviation with the experimental data due to relatively small sputtering rate on the sample surface. The simulation results showed about 10.6% tolerance from the measured data at 200 pA. On the other hand, the improved analytical model of damaged layer was matched well with experimental XTEM (cross-sectional transmission electron microscopy) data.