• Title/Summary/Keyword: Stream Characteristic

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Sensitivity Enhancement of Spirometer Employing Ultrasonic Method

  • Han, Seung-Heon;Kim, Young-Kil
    • Journal of Biomedical Engineering Research
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    • v.26 no.6
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    • pp.351-356
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    • 2005
  • Respiration measurement method using an ultrasound sensor is influenced very little by an error of inertia and pressure. This device measures the amount and flow of respiration using a delivery speed difference of the ultrasound waves that are a return format by the pneumatic stream that is a flogging of ultrasound waves during transmission and receipt as having used a characteristic of ultrasound waves. This paper examines improving the sensor's sensitivity during transmission and receipt of the signal. Because the measurement must be performed on patients, clinicians need to be sure that it is accurately measuring even very weak breathing.

Left ventricular-right atrial communication (One case report) (좌심실-우심방 단락 치험 1례)

  • 오세웅
    • Journal of Chest Surgery
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    • v.19 no.4
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    • pp.683-687
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    • 1986
  • A direct communication between the left ventricle and right atrium is a relatively uncommon defect. Familiarity with this anomaly has become increasingly important, however, since the preoperative findings may be identical with those of an atrial septal defect. The left ventricle is directly related to the right atrium over. an area of the membranous ventricular septum which extends superior to the septal attachment of the right atrioventricular valve in the LV-RA communication. The clinical triad of a ventricular septal defect murmur, cardiac enlargement, and an arteriovenous shunt at atrial level is characteristic of the malformation. A 2-year-old boy with left ventriculo-right atrial communication has operated at the Maryknoll Hospital. Under the cardiopulmonary bypass, the atrium was opened, there was a jet-blood stream just above the atria-ventricular portion adjacent to the septal leaflet of the tricuspid valve.

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Computer Simulation of Ink Flow In the Various Types of Gravure Cell (그라비어 셀의 형태에 따른 잉크 유동 시뮬레이션에 관한 연구)

  • Lee, Soon-Sim;Youn, Jong-Tae
    • Journal of the Korean Graphic Arts Communication Society
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    • v.23 no.2
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    • pp.59-75
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    • 2005
  • In gravure printing, the amount of ink from cells has a great effect on the qualities of final printed products. And printability of final products is determined by every kinds variables. Ink transfer process is not verified scientifically because gravure cell is of small size and print speed is rapid. Therefore in order to study of ink transfer mechanism, this study is using the Computational Fluid Dynamics Evaluation. Polyflow 3-10 simulation software is used for considering of non-Newtonian flow. Among the various factors, this study have dealt with gravure cell types used computer simulation in order to define distinctive features in ink flow and transfer. The results of simulation, it defined the distribution of pressure, speed, stream function, viscosity, shear rate during the gravure printing. It is fined out the difficulties and characteristics according to the shape of cell types. Through this study, the condition of gravure printing is depending on the print condition and characteristic of cells.

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An Experimental Study on the Local Effective Thermal Conductivity in Packed Bed (충전층에서의 국부유효열전도율에 관한 실험적 연구)

  • Lee J.S;Yang H.J;Choi K.K;Seo J.Y
    • The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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    • v.16 no.1
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    • pp.81-88
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    • 1987
  • In this paper, the local effective thermal conductivities and calculated by using the actual temperature distribution in packed bed. The variations of these are investigated for radius and air stream direction, flow rate and particle diameter. The resulting local effective thermal conductivi-ties are classified in the inner zone of bed and vicinity zone of the wall surface. Also these are related to dimensionless axial direction position, radius direction position, and particle diameter and Reynolds number which uses particle diameter as the characteristic length. If these correla-tions are represented by function, the equation is showed in Eq. (3-4). This equation is well satisfied with experimental results within $\pm25\%.$

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Dynamic Modeling of PIG Flow through Curved Section in Natural Gas Pipelines (천연가스배관내 곡선 영역을 지나는 피그흐름의 동적모델링)

  • Nguyen, Tan Tien;Yoo, Hui-Ryong;Rho, Yong-Woo;Kim, Sang-Bong
    • Proceedings of the KSME Conference
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    • 2001.06b
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    • pp.247-252
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    • 2001
  • In this paper, dynamic modeling and its analysis for the PIG flow through $90^{\circ}$ curved pipe with compressible and unsteady flow are studied. The PIG dynamics model is derived by using Lagrange equation under assumption that it passes through 3 different sections in the curved pipeline such that it moves into, inside and out of the curved section. The downstream and up stream flow dynamics including the curved sections are solved using MOC. The effectiveness of the derived mathematical models is estimated by simulation results for a low pressure natural gas pipeline including downward and upward curved sections. The simulation results show that the proposed model and solution can be used for estimating the PIG dynamics when we pig the pipeline including curved section.

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An Experimental Study on the Flow Characteristics in Highly Viscous Liquid by Multi-Nozzle Bubbling (고점성 액체 내부에서의 다중 노즐 버블링에 의한 유동특성에 대한 실험적 연구)

  • Kim, Hyun-Dong;Ryu, Seung-Gyu;Kim, Kyung-Chun
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.31 no.2 s.257
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    • pp.195-201
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    • 2007
  • A visualization study of flow characteristics in a mixer using multi-nozzle bubbling was performed. The mixer is filed with liquid glycerin (dynamic viscosity = $1000mPa{\cdot}s\;at\;25^{\circ}C$) and convective mixing is induced by air bubbles generated from 9 orifices installed on the bottom of the mixer. To visualize the flow field, PIV (Particle Image Velocimetry) system consisting of 532nm Nd:YAG laser, $2k{\times}2k$ CCD camera and synchronizer is adopted. The bubbles generated with uniform size and frequency form bubble stream and bubble streams rise vertically without interaction between bubble streams. Mixing efficiency is affected by the height of bubbler and the effective height of bubbler is 20nm from the bottom of the mixer.

A Study on Characteristics of Water Pollution in Woopo-Mokpo Wetlands (우포·목포늪 수질오염특성 연구)

  • Lee, Tae-Young;Yoon, Sung-Yoon
    • Journal of Wetlands Research
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    • v.1 no.1
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    • pp.1-5
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    • 1999
  • We could know that the Woopo and Mokpo wetlands, which have the typical colony structure in the agricultural area of korea, had a characteristic which the pollution sources of water are scattered widely and it is caused by sewage, livestock wastewater and non point sources. As the result of an examination of water, the concentration of T-N was measured highly within five grade in the lake standard. If we build natural domestic treatment system in Taehap-myon, lbang-myon and Yuo-myon, which are located at the upper stream of wetlands, we can remove SS, BOD, COD and T-N largely.

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Analysis of the Thermal Environmental Characteristic for Musim Stream (청주시 무심천 주변의 열 환경 특성 분석)

  • Park, Jin-Ki;Park, Jung-Haw;Na, Sang-Il
    • Proceedings of the Korea Water Resources Association Conference
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    • 2010.05a
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    • pp.1016-1020
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    • 2010
  • 본 연구는 충북 청주시에 위치한 무심천 주변을 대상으로 하천이 도시 주변 열 환경에 미치는 영향에 대해 원격탐사(Remote Sensing; RS)기법을 이용하여 분석하였다. 열 환경 특성 분석 순서는 먼저 Landsat 5 TM 위성영상의 열적외 밴드를 이용하여 대상지역의 표면 온도(Land Surface Temperature; LST)를 추출하였다. 다음으로 추출된 LST를 이용하여 무심천을 중심으로 주변의 공업단지와 주거지, 산림 지역의 지표면 온도 분포를 비교 분석하여 하천이 주변의 열 환경에 미치는 영향을 정량화하였다. 또한 공간적 특성 분석을 위해 등온선을 작성하여 하천 주변 열 환경을 파악하였다. 그 결과 온도분포에 따른 열 이동의 크기와 방향을 확인할 수 있었고 열 분포의 공간분포는 공업지>주거지>하천>산림 순으로 나타나 토지이용특성에 따른 열 분포의 경향을 파악할 수 있었다.

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A study on particular intention with water space of Tong-do temple (통도사에 나타난 수공간의 의도성에 관한 연구)

  • Cho, Nam-Du;Kim, Su-Young
    • Journal of The Korean Digital Architecture Interior Association
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    • v.3 no.2
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    • pp.8-13
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    • 2003
  • The purpose of this study was to analyze the Site layout of Buddhist Architicture by water space of landscape architecture. As a result, the following fact is identified; We knew that land scape of Buddhist Architecture is intentional device. Example from the Tong-do Temple, it leads cleary the intention of water-space. The case of Tong-do Temple, water space is divided into Yeon-ji(lotus pond) and the Yeong-gi(shadow pond) and Gye-ryu(mountain stream). The viewing intention of Gu-Ryong-ji where Yong-ji the construction intention characteristic is positive it was intended there is a possibility of knowing. From the research which it sees it is limited in case of the Tong-do Temple tries to search a concrete instance. but on this outside many multiple architectural space uses water space and It creates the space where it leads the harmony of architecture and intention it was plentifully included.

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A Study on the Representation Techniques of Glass Material in Contemporary Interior Space Design (현대 실내공간디자인에 있어서 유리재료의 표현기법에 관한 연구)

  • Kim, Eun-Jung;Hong, Kwan-Seon
    • Proceedings of the Korean Institute of Interior Design Conference
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    • 2007.11a
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    • pp.134-138
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    • 2007
  • Presents age is diversified in all genres by fast development of information and digital, and expression of fixing is not. Architecture and interior space design is showing new paradigm through dematerializing, ex-formal, nonlinear. Glass material is expressing by various technique in space and outer skin to introduction of digital media and a high-tech technology. Expressive characteristics and Techniques of this glass material are showing form of homogenized life in this age, simulated life. Therefore, this study does theoretical investigation through dematerializing of glass material, and analyzes works after 2000. Wish to understand stream of indoor design of present age after analyzes expression special quality and technique of glass material that reflect age and make a study of symbolic expression characteristic.

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