• 제목/요약/키워드: Lateral spreading

검색결과 51건 처리시간 0.034초

하천수 플룸 횡방향 퍼짐의 해석해 (A Hydrodynamic Solution for the Lateral Spreading of a River Plume)

  • Yu, Hong-Sun;Lee, Jun
    • 한국해안해양공학회지
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    • 제5권4호
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    • pp.302-306
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    • 1993
  • 하수제트플룸내에서 플룸과 주변해수와의 밀도차가 Gauss 분포를 나타내고 있다는 가정하에 하구만에 흘러 나오는 하수 플룸의 횡방향 퍼짐속도의 해석해를 구하였다. 이 가정을 도입하므로써 얻는 이점은 첫째, 혼합과정의 결과가 밀도분포에 반영되어 있으므로 이 문제를 다루는데 있어서 혼합과정에 대한 고려를 할 필요가 없다는 점이고, 둘째로는 밀도분포가 알려져 있으므로 그로부터 압력경사력을 구하여 운동방정식에 대입, 문제를 쉽게 풀 수 있다는 점이다. 이론해를 낙동강 하수플룸의 관측결과와 비교해 본 결과, 비교적 잘 일치함을 발견하였고 본 연구의 이론식이 하수플룸의 퍼짐을 다루는데 유용하게 쓰일 수 있음을 확인하였다.

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흉벽 외측을 타고 내려온 비전형성 하행 경부 괴사성 근막염 1예 (Atypical Type of Descending Necrotizing Fasciitis Spreading into the Lateral Chest Wall: Case Report)

  • 이용직;이종철;이호민;김정원;정종필;박창률
    • 대한기관식도과학회지
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    • 제17권1호
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    • pp.61-64
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    • 2011
  • Cervical necrotizing fasciitis is a rare but well known life-threatening soft tissue infection primarily affecting the superficial and deep cervial fascial planes. It may rapidly spread into the mediastinum along fascial planes. So, if proper diagnosis and prompt surgical debridement is delayed, the infection may cause descending necrotizing mediastinitis with extensive necrosis of overlying skin, destroying fascia and muscle. Therefore, the key to the successful outcome is early recognition and rapid initiation of definitive radical debridement. The authors report, along with a literature review, a case of cervical necrotizing fasciitis with atypical spreading into the lateral chest wall.

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종방향 영구지반변형에 의한 매설관로의 거동 특성 해석 (Response Analysis of Buried Pipelines Considering Longitudinal Permanent Ground Deformation)

  • 김태욱
    • 한국지진공학회:학술대회논문집
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    • 한국지진공학회 2000년도 추계 학술발표회 논문집 Proceedings of EESK Conference-Fall 2000
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    • pp.184-191
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    • 2000
  • In this research, a numerical model is developed for analysis of buried pipelines considering longitudinal permanent ground deformation(PGD) due to liquefaction induced lateral spreading. Buried pipelines and surrounding soil are medeled as continuous pipelines using the beam elements and a series of elasto-plastic springs uniformly distributed along the pipelines, respectively. Idealized various PGD patte군 based on the observation of PGD are used as a loading configuration and the length of the lateral spread zone is considered as a loading parameter. Numerical results are verified with other research results and efficient applicability of developed procedure is shown. Analyses are performed by varying different parameters such as PGD pattern, pipe diameter and pipe thickness. Results show that response of buried pipelines are more affected by pipe thickness than pipe diameter. Finally, the critical length of the lateral spread zone and the critical magnitude of PGD which cause yielding, local buckling or tension failure are proposed for the steel pipe which are normally used in Korea.

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타(舵)의 효과(效果)를 고려(考慮)한 시간영역(時間領域)에서의 선체(船體) 횡운동응답(橫運動應答) (The Lateral Motion Responses of a Ship with Rudder Effects in the Time Domain)

  • 공인영;이기표
    • 대한조선학회지
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    • 제21권3호
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    • pp.35-42
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    • 1984
  • In this paper, the lateral motions of a ship in the time domain are treated by applying the Impulse Response Function Technique. The acceleration, and displacement of a ship in the time domain are needed for the purpose of such automatic controls as the fire control system and the auto-pilot of ocean-going vessels, etc. The response Amplitude Operators of a ship are calculated by the Strip Method of Salvesen-Tuck-Faltinsen, and the Pierson-Moskowitz Spectrum multiplied by spreading function is used to represent the short crested ocean waves. The ocean wave elevations in the time domain are simulated according to the Method of Borgman. Finally the rudder effect is considered by simply adding the force and moment due to the rudder to the wave exciting force. And the results of lateral motions with and without rudder are shown.

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Occurrence of Stolbur Phytoplasma Disease in Spreading Type Petunia hybrida Cultivars in Korea

  • Chung, Bong Nam;Jeong, Myeong Il;Choi, Seung Kook;Joa, Jae Ho;Choi, Kyeong San;Choi, In Myeong
    • The Plant Pathology Journal
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    • 제29권4호
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    • pp.465-470
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    • 2013
  • In January 2012, spreading type petunia cv. Wave Pink plants showing an abnormal growth habit of sprouting unusual multiple plantlets from the lateral buds were collected from a greenhouse in Gwacheon, Gyeonggi Province, Korea. The presence of phytoplasma was investigated using PCR with the primer pairs P1/P6, and R16F1/R1 for nested-PCR. In the nested PCR, 1,096 bp PCR products were obtained, and through sequencing 12 Pet-Stol isolates were identified. Comparison of the nucleotide sequences of 16S rRNA gene of the 12 Pet-Stol isolates with other phytoplasmas belonging to aster yellows or Stolbur showed that Pet-Stol isolates were members of Stolbur. The presence of phytoplasma in petunia was also confirmed by microscopic observation of the pathogens. In this study, Stolbur phytoplasma was identified from spreading type petunia cultivars by sequence analysis of 16S rRNA gene of phytoplasma and microscopic observation of phytoplasma bodies. This is the first report of Stolbur phytoplasma in commercial Petunia hybrida cultivars.

경추간공 경막외 조영술의 양상에 관한 분석 (An Analysis of Pattern of Transforaminal Epidurography)

  • 홍지희
    • The Korean Journal of Pain
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    • 제19권2호
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    • pp.175-180
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    • 2006
  • Background: A transforaminal epidural steroid injection has been used for the treatment of radicular arm or leg pain, which has the advantage of ventral epidural spreading compared to either an interlaminar or caudal approach. However, several factors are known to affect the epidural spread pattern of contrast dye; therefore, the injected medication can not be delivered to the target site. The objective of our study was to observe any differences in the contrast flow patterns according to several factors. Methods: A total of 34 epidurographies in 29 patients, who underwent fluoroscopically guided transforaminal epidural steroid injections, were evaluated. After confirming the location of the needle tip within the anterior superior aspect of the neural foramen in the lateral view, and at the 6 o'clock position to the pedicle in the anteroposterior view, 2 ml of contrast dye was injected. The contrast flow patterns of ventral, ventral and dorsal, and dorsal epidural filling were analyzed, according to age, gender, magnetic resonance imaging finding and history of previous back surgery. Results: Ventral contrast flow occurred in 30 out of the 34 epidurographies (88%). Both ventral and dorsal contrast flow patterns were observed 13 out of 16 (81%) patients in the older age group. Also, both ventral and dorsal contrast flow patterns were observed in 16 out of 18 (88%) patients with spinal stenosis. Conclusions: Transforaminal epidural steroid injections, performed uner fluoroscopy, provide excellent nerve root filling and ventral epidural spreading. Patients with spinal stenosis or an old age have both ventral and dorsal epidural spreading patterns.

ANALYSIS OF VELOCITY STRUCTURE OF WALL JET ORIGINATING FROM CIRCULAR ORIFICES IN SHALLOW WATER

  • Kim, Dae-Geun;Seo, Il-Won
    • Water Engineering Research
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    • 제3권4호
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    • pp.235-245
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    • 2002
  • In this study, breakwater model which has several outlet pipes to discharge water is settled in the experimental open channel and mean velocity distributions of multi wall jet are measured. The length of flow of flow establishment of wall jet is shorter than that of free jet and decay rate of jet centerline longitudinal velocity along x is linear in 0.3 $\leq$ x/$\l_q$ $\leq$ 17. The rate of vertical width and lateral width spreading of multi wall jet is respectively 0.0753, 0.157~0.190.

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천해역에 방류되는 원형 다공바닥젵의 유속구조 (Velocity Structure of Wall Jet Originating from Circular Orifices in Shallow Water)

  • 김대근;서일원
    • 한국환경과학회지
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    • 제11권10호
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    • pp.1039-1044
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    • 2002
  • In this study, breakwater model which has several outlet pipes to discharge water is settled in the experimental open channel and mean velocity distributions of multi wall jet are measured. The length of zone of flow establishment of wall jet is shorter than that of free jet and decay rate of jet centerline longitudinal velocity along x is linear in $0.3{leq}x/I_p{leq}17$. The rate of vertical width and lateral width spreading of multi wall jet is respectively 0.0753, 0.157.

경부경막외차단 시 약물의 용량에 따른 약물 분포 범위: 5 ml와 10 ml 주입량에 대한 비교 연구 (Vertebral Spreading Segments of Cervical Epidural Injection: a Comparative Study with 5 ml and 10 ml of Injected Volume)

  • 이상은;한경림;김찬;채윤정;유지영
    • The Korean Journal of Pain
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    • 제19권2호
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    • pp.181-186
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    • 2006
  • Background: Although cervical epidural block can be a useful therapeutic treatment for head, neck and upper extremities pain, there is no consensus regarding the volume of injection required for pain management. Herein, the spreading in the vertebral segments after a cervical epidural injection of either a 5 or 10 ml volume was studied. Methods: A total of 78 patients, suffering from head, neck and upper extremity pain, were selected. Cervical epidural blocks were performed consecutively with 5 ml (n = 42) and 10 ml (n = 36) of 0.4% mepivacaine and 222 mg I/ml iopamidol at the C7⁣-T1 levels. Both anteroposterior (AP) and lateral radiographs were obtained under fluoroscopy, and the upper and lower epidural spreading of the contrast media in relation to the vertebral level was evaluated. Results: The cervical epidural blocks were performed without complications. The rostral spreading of the contrast media in the vertebral segments in groups 1 and 2 were $5.6{\pm}1.1$ and $6.1{\pm}1.1$, respectively. The caudal spreading of the contrast media in the vertebral segments in groups 1 and 2 were $5.4{\pm}3.4$ and $7.2{\pm}3.9$, respectively. The total numbers of segments with vertebral spreading of the contrast media in both directions showed significant differences between the two groups. The numbers of patients who showed spreading of the contrast media up to C2 vertebral segment showed no significant differences between the two groups. Conclusions: 5 and 10 ml epidural injection volumes may be adequate for the spread of contrast media to the entire cervical spine. A 5 ml epidural injection volume, compared to a 10 ml volume, may be ample when considering the possibility of unnecessary caudal spreading of drugs and volume related complications in the management of head, neck and upper extremity pain.

저전압 VDMOS의 ON-저항 모델 (An Advanced Model of on-Resistance for Low Voltage VDMOS Devices)

  • 김일중;김성동;최연익;한민구
    • 대한전기학회논문지
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    • 제41권3호
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    • pp.267-273
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    • 1992
  • An advanced on-resistance model of VDMOS devices in the low voltage regimes is proposed and verified by 2-D device simulations. The model considers the lateral gaussian doping profiles in the channel region and exact current spreading angles in the epitaxial layer for both linear and cellular geometries by employing the conformal mapping, It is found out that the on-resistance of low voltage VDMOS may be overestimated considerably if it is analyzed by the conventional method. The 2-D device simulation results show that the proposed model is valid for the VDMOS devices in the low voltage regimes.

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