• Title/Summary/Keyword: Prevent lateral flow

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Distally Based Anterolateral thigh Pedicled Flap in the Reconstruction of Defect Around Knee (역혈류성 전외측대퇴 혈관경피판을 이용한 무릎 주위 결손의 재건)

  • Park, Sang-Soon;Shim, Jeong-Su
    • Archives of Plastic Surgery
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    • v.37 no.6
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    • pp.769-774
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    • 2010
  • Purpose: As the soft tissue defect around the knee is difficult to reconstruct, local flap or free flap is used. Distally based anterolateral thigh pedicled flap introduced by Zhang uses sufficient reverse flow supplied from the vascular network around the knee. We report successful reconstruction of defect around knee by this method. Methods: Four patients with skin & soft tissue defect around knee have been treated for reconstruction using the distally based anterolateral thigh pedicled flap. First, the doppler was used to check the perforator flap of the descending branch of the lateral circumflex femoral artery and to draw and dissect the perforator flap as much as needed. After the dissection, the proximal of the descending branch was clamped and checked for sufficient supply of blood flow from the reverse flow and then ligated. It was dissected along the descending branch and in order to prevent damage to the joined parts of the descending branch and the lateral superior geniculate artery, a more careful ligation was done starting from 10 cm superior to the knee. The defect was reconstructed after securing enough vascular pedicle to cover all the damaged parts. Results: Not all patients suffered from flap necrosis. In case of the patient with chronic osteomyelitis, slight venous congestion was observed right after the surgery but it disappeared the following day. All three patients had no occurences of additional complications. Conclusion: Distally based anterolateral thigh pedicled flap was enough to provide large flap for knee reconstruction. It had sufficient blood flow and vascular pedicle. It also had taken short operation time compared to the free flap operation. The distally based anterolateral thigh pedicled flap used by the authors is a very useful way of reconstructing the area around knee.

An Experimental Study on the Estimation of Optimum Length of Soil Flow Protector with Wall Stiffness (벽체 강성에 따른 토사유입차단판의 최적 길이 산정에 관한 실험적 연구)

  • Yoo, Jae-Won;Seo, Min-Su;Son, Su-Won;Im, Jong-Chul
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.39 no.6
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    • pp.789-799
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    • 2019
  • The settlement hardly occurs in structures supported by pile foundation such as abutment, culvert but a cavity is formed in the lower part of a structure. As a result, soil discharged from the lateral ground to the cavity accelerates the settlement of the lateral ground of the structure, resulting in a larger settlement. Therefore, in order to prevent problems caused by cavity under the structure supported by pile foundation, soil Flow Protector (briefly called 'FLP'), which can be easily installed on the side of structure, was developed. In this study, an laboratory model test was carried out to prove the reduction effect of settlement and to estimate the optimal installation length of the FLP. As a result, the installation of the FLP reduced the settlement of the lateral ground and prevented the leakage of lateral ground soil into the cavity. If the stiffness of the FLP is small, the state or active earth pressure is generated in the upper part, which is not favorable for stability. But if the stiffness of the FLP is high enough, the passive earth pressure area is generated in the upper part, which will be advantageous for the stability. Also, the increased installation length of FLP is effective to reduce the settlement. And the ratio of the optimal length of the FLP to the box structure height (H = 250 mm) are flexible FLP 1.38, stiff FLP 0.73.

Centrifuge Modeling on Lateral Flow of Soft Soils and Displacement of Bridge Abutment on the Composite Ground (복합지반상 교대변위 및 지반 측방유동에 관한 원심모델링)

  • Heo, Yol;Park, Sunghun;Yun, Seokhyun;Kwon, Seonuk
    • Journal of the Korean GEO-environmental Society
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    • v.8 no.5
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    • pp.39-46
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    • 2007
  • In this study, the centrifuge tests were performed to investigate the lateral flow behavior and stability of the ground improved by SCP. The centrifuge tests were fulfilled in the case of the back of abutment filled by EPS (case 1) and soil (case 2), and the potentiometer was installed on the abutment and embankment to measure the vertical and horizontal displacement at the top of abutment. As a result, the vertical displacement measured at the back of abutment was maximum 2.1 m, which was about 12% if compared with the height of embankment. In the case of the back of abutment filled by soil, the vertical and horizontal displacement measured at the top of abutment was 10 cm and 1.1 m, respectively, which exceeded the allowable horizontal displacement. On the other hand, in the case of the back of abutment filled by EPS, the vertical displacement of abutment did nor occur and the horizontal displacement was 1.4 cm. Therefore, the effect of SCP improvement with EPS method adopted to prevent the lateral flow and assure the stability of embankment on the soft ground was far superior.

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Long-term Behavior Characteristics of Backfilled Ground by EPS (EPS로 뒷채움된 지반의 장기거동특성)

  • Chun, Byung-Sik;Jung, Chang-Hee;Choi, Hui-Rim
    • Journal of the Korean Geotechnical Society
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    • v.23 no.10
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    • pp.151-161
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    • 2007
  • EPS provides a superb self-sufficient stability. Studies on the process of EPS construction method focus on the inchoate phase of general construction, which is increasingly applied to construction sites throughout the world. Unfortunately, there has been little study on the durability and long-term soil behavior involving EPS materials. In this study, the boring, in-site and laboratory tests were conducted to examine the long-term soil behavior in the back-filling of alternating behind the side to which EPS was applied. And results of finite element analysis considering various test results and the soil behavior data measured during the construction show that EPS construction method is a superb process that relieves the load and consequently reduces the settlement, alleviates the stress on the abutment, and prevents lateral flow.

Application of 3D point cloud modeling for performance analysis of reinforced levee with biopolymer (3차원 포인트 클라우드 모델링 기법을 활용한 바이오폴리머 기반 제방 보강공법의 성능 평가)

  • Ko, Dongwoo;Kang, Joongu;Kang, Woochul
    • Journal of Korea Water Resources Association
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    • v.54 no.3
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    • pp.181-190
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    • 2021
  • In this study, a large-scale levee breach experiment from lateral overflow was conducted to verify the effect of the new reinforcement method applied to the levee's surface. The new method could prevent levee failure and minimize damage caused by overflow in rivers. The levee was designed at the height of 2.5 m, a length of 12 m, and a slope of 1:2. A new material mixed with biopolymer powder, water, weathered granite, and loess in an appropriate ratio was sprayed on the levee body's surface at a thickness of about 5 cm, and vegetation recruitment was also monitored. At the Andong River Experiment Center, a flow (4 ㎥/s) was introduced from the upstream of the A3 channel to induce the lateral overflow. The change of lateral overflow was measured using an acoustic doppler current profiler in the upstream and downstream. Additionally, cameras and drones were used to analyze the process of the levee breach. Also, a new method using 3D point cloud for calculating the surface loss rate of the levee over time was suggested to evaluate the performance of the levee reinforcement method. It was compared to existing method based on image analysis and the result was reasonable. The proposed 3D point cloud methodology could be a solution for evaluating the performance of levee reinforcement methods.

Spalling Resistance of High Strength Concrete Using Non-Stripping Form (비탈형 거푸집에 의한 고강도 콘크리트의 폭렬방지)

  • You, Ji-Young;Han, Chang-Pyung;Jee, Suk-Won;Han, Min-Cheol;Yang, Seong-Hwan;Han, Cheon-Goo
    • Proceedings of the Korea Concrete Institute Conference
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    • 2008.04a
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    • pp.865-868
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    • 2008
  • As a part of a series of study, this study reviewed the fire proof characteristics of high performance concrete RC column members using non-stripping form that accompanied metal lath lateral confinement to prevent spalling of high performance concrete which is increasingly used recently, and the results are as follows. Flow and air amount both satisfied target range, and compressive strength, over 80MPa at age 28 days, showed high strength range. As for spalling characteristics, in the case of plain in which no fiber is mixed, severe spalling occurred, and in the case of 0.05% nylon("NY" hereinafter)+polypropylene("PP" hereinafter) fiber mixture, only surface area experienced partial spalling. Regarding non-stripping form changes, both non-stripping 25-20 and non-stripping 50-20 experienced spalling at finish material area, and non-stripping 50-20 showed better spalling proof performance than non-stripping 25-20. In the case of non-stripping 50-40, spalling was prevented, and while mass reduction rate was less than 10%, its temperature hysteresis showed the most excellent fire proof performance with base metal surface area maximum temperature $376.1^{\circ}C$.

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Liquefaction Prevention and Damage Reduction Effect of Reinforcement by Sheet Pile Using 1-G Shaking Table Test (1-G 진동대 실험을 이용한 시트파일 보강재의 액상화 및 피해 방지 효과)

  • Sim, Sung Hun;Yoon, Jong Chan;Son, Su Won;Kim, Jin Man
    • Journal of the Earthquake Engineering Society of Korea
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    • v.24 no.5
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    • pp.211-217
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    • 2020
  • Earthquake preparedness has become more important with recent increase in the number of earthquakes in Korea, but many existing structures are not prepared for earthquakes. There are various types of liquefaction prevention method that can be applied, such as compaction, replacement, dewatering, and inhibition of shear strain. However, most of the liquefaction prevention methods are applied before construction, and it is important to find optimal methods that can be applied to existing structures and that have few effects on the environment, such as noise, vibration, and changes in underground water level. The purpose of this study is to estimate the correlation between the displacement of a structure and variations of pore water pressure on the ground in accordance with the depth of the sheet file when liquidation occurs. To achieve this, a shaking table test was performed for Joo-Mun-Jin standard sand and an earth pressure, accelerometer, pore water pressure transducer, and LVDT were installed in both the non-liquefiable layer and the liquefiable layer to measure the subsidence and excess pore water pressure in accordance with the time of each embedded depth. Then the results were analyzed. A comparison of the pore water pressure in accordance with Hsp/Hsl was shown to prevent lateral water flow at 1, 0.85 and confirmed that the pore water pressure increased. In addition, the relationship between Hsp/Hsl and subsidence was expressed as a trend line to calculate the expected settlement rate formula for the embedded depth ratio.

Clinical usefulness of rapid antigen test to detect respiratory syncytial virus infection (Respiratory syncytial virus 감염진단을 위한 신속항원검사의 유용성)

  • Kim, Hyung Su;Kim, Hee La;Park, Ki Hyung;Cho, Kyung Soon
    • Clinical and Experimental Pediatrics
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    • v.51 no.10
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    • pp.1071-1076
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    • 2008
  • Purpose : Respiratory syncytial virus (RSV) is the most frequent cause of lower respiratory infections in infants and young children. Early detection allows quarantining of infected inpatients to prevent nosocomial transmission and to choose a treatment. To achieve rapid reporting, to facilitate prompt antiviral therapy, and to avoid unnecessary use of antibiotics, an easy, rapid diagnostic method for RSV is needed. We evaluated a lateral flow immunochromatography (RSV Respi-Strip test) and EIA (Enzyme immuno assay) compared to RT-PCR. Methods : From April 2007 to March 2008, 112 consecutive respiratory specimens (nasopharyngeal aspirates, throat swabs, tracheal aspirates, sputum) from patients who were suffering from the clinical signs and symptoms of respiratory tract infection were enrolled in Busan. A total of 112 patients were tested with RSV Respi-Strip (Corio-BioConcept, Belgium), EIA, and RT-PCR at the same time. Results : Of the 112 specimens tested, the number of children who showed positive results at RT-PCR and Respi-Strip were 45 and 42, respectively. The Respi-Strip rapid antigen test had a sensitivity of 88% and a specificity of 94%. The positive and negative predictive values were 90% and 92%, respectively. The agreement was 83%. Conclusion : In our study, the rapid antigen test had as much sensitivity as any method for detection of RSV. The test has many advantages such as easy performance, simple interpretation, and rapid results. If the rapid antigen test is widely applied in the clinical setting, the may be useful for diagnostic and epidemiological studies of RSV infection.

Clinical Usefulness of Rapid Antigen Test on the Diagnosis of Influenza (인플루엔자 진단을 위한 신속 항원검사의 유용성)

  • Kim, Jae Seon;Choi, Hyon Joo;Ahn, Young Min;Hwang, Young Ok
    • Clinical and Experimental Pediatrics
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    • v.48 no.12
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    • pp.1348-1353
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    • 2005
  • Purpose : Influenza is a respiratory disease which prevails widely every year and shows high morbidity and mortality among not only chronic invalids and the old, but also among infants and young children. To prevent community-acquired influenza infection, to facilitate prompt antiviral therapy and to avoid unnecessary use of antibiotics, an easy, rapid diagnostic method for the influenza virus is needed. We evaluated a lateral-flow immunoassay(QuickVue Influenza Test), compared to viral culture. Methods : During two consecutive years from Jan. 2004 to June 2004 and from Feb. 2005 to Jan. 2005, 408 patients who were suffering from fever, cough and/or sore throat and myalgia were enrolled in our study. A total of 408 patients were tested with $QuickVue^{(R)}$(Quidel Co., San Diego, USA) influenza rapid antigen test and virus cultures at the same time. Results : Of the 408 patients tested, children who showed positive results at the virus culture numbered 77; among them, 55(71.4 percent) were type A/H3N2 and 22(28.5 percent) were type B. QuickVue influenza test had a sensitivity of 71.4 percent and a specificity of 95.8 percent. The positive and negative predictive values were 79.7 percent and 93.5 percent, respectively. Conclusion : In our study, this test had comparable high sensitivity and high specificity and many advantages, such as being easy to perform and simple to interpret, and showing rapid results. If rapid influenza antigen tests are widely applied in the clinic, we can begin treatment more rapidly and reduce influenza complications and the abuse of antibiotics.