• Title/Summary/Keyword: Transitional zone

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Behaviors of Settlement for Transitional zone with Moving Wheel Loading (이동하중을 고려한 토공-접속구간 침하거동)

  • Choi, Chan-Yong;Lee, Jin-Wook
    • Proceedings of the KSR Conference
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    • 2008.06a
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    • pp.238-242
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    • 2008
  • Transitional zones, one of the typical weak area of earthworks, require lasting a maintenance work due to a differential stiffness of substructures. It is very difficult problem that transition zone was perfectively prevented against a differential settlement. The transitional zone will deteriorate at an accelerate rate. This may lead to pumping ballast, swinging or hanging sleepers, permanent rail deformations, worn track components, and loss of surface and gauge. In this study, it is performed that settlement behavior in transitional zone was compared with small model test.

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Behavior of Failure for Embankment and Spillway Transitional Zone of Agriculture Reservoirs due to Overtopping (농업용 저수지 월류시 제체와 여수토 접속부의 붕괴거동)

  • Noh, Jae Jin;Lee, Dal Won
    • Journal of The Korean Society of Agricultural Engineers
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    • v.56 no.1
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    • pp.71-79
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    • 2014
  • In this study, an experiment with large-scale model was performed according to raising the embankment in order to investigate the behavior of failure for embankment and spillway transitional zone due to overtopping. The pore water pressure, earth pressure, settlement and failure pattern by a rapid drawdown and overtopping were compared and analyzed. The pore water pressure and earth pressure at spillway transitional zone by overtopping increased a rapidly with the expansion of seepage erosion, but the crest showed a smally change due to effect of the inclined core type. And it is considered an useful data that can accurately estimate the possibility of failure of the reservoirs. A settlement at overtopping decreased a rapidly due to failure of crest. The relative settlement difference due to change of the water level at the upstream and downstream slope cause increase largely crack of crest. The behavior of failure by overtopping was gradually enlarged towards reservoirs crest from the bottom of the spillway transition zone, the inclined core after the raising the embankment was influenced significantly to prevent the seepage erosion.

Effectiveness of Reinforcement for Transitional Zone between Tunnel and Earthwork Using the Large Sleeper (대형침목을 이용한 터널/토공 접속구간의 보강효과)

  • Choi, Chan-Yong;Lee, Jin-Wook;Kim, Hun-Ki
    • Journal of the Korean Society for Railway
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    • v.13 no.2
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    • pp.214-221
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    • 2010
  • The transitional zone between tunnel and earthwork is one of the most vulnerable areas site for railway lines and because of differential settlement due to different stiffness of each supporting layer, it has to conducted a maintenance work constantly. In this study, it is conducted to compare the effect of reinforcement by wheel load and displacement of the sleepers after existing sleepers are replaced with the large sleepers for 20m long in-field transitional zone. Also, numerical parametric study using multi-layer elastic method has been performed to compare rail force, settlement and stresses of ballast while varying size and space of the sleeper. The field test and numerical results show that replacing the large sleepers improves about 10% of total settlement and coefficient of wheel force than conventional sleepers. Effectiveness of improvement is about 9.3%, 4%, 14.5% for rail seat force, settlement of sleepers and ballast pressure respectively with size of sleepers.

The Case Study on Thoraco-lumbar junction and Lumbo-sacral junction Transitional Zone Syndrome. (복합적으로 병발한 등-허리, 허리-엉치 이행부위 증후군에 대한 증례를 통한 고찰)

  • Hwang, Eun-Mi;Jung, Min-Gyu;Park, Young-Hoi;Keum, Dong-Ho
    • The Journal of Churna Manual Medicine for Spine and Nerves
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    • v.5 no.2
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    • pp.113-125
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    • 2010
  • Objectives: We have evaluated the effects of conservative treatment on one patient who was diagnosed to thoraco-lumbar junction and lumbo-sacral junction transitional zone syndrome. so, we investigate thoraco-lumbar junction and Jumbo-sacral junction tranzitional zone syndrome that was suggested by Maigne R. Methods : One patient was diagnosed as T12-L1 herinated intervetebral disc through MRI. We diagnosed the patient to transitional zone syndrome by symptoms and physical examination and used Acupuncture therapy, Cox technique to the patient. We measured Visual Analog Scale(VAS) before and after treatment. Results: After treating Acupuncture therapy, Cox technique in the case, We find out that the patient was improved. VAS score changed from 7 to 2 and physical examinations are improved. Conclusions: We improved the patient who had thoraco-lumbar junction and lumbo-sacral junction transitional zone syndrome by Cox technique and Acupuncture therapy, and we found that thoraco-lumbar junction related lumbo-sacral junction.

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A study on Response Characteristics for the Reinforced Abutment for Railroads by Numerical Analyses (수치해석을 통한 철도보강교대의 응답 특성 연구)

  • Kim, Dae-Sang;Jeong, Rag-Gyo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.11
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    • pp.7949-7956
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    • 2015
  • This paper introduced the RAR(Reinforced Abutment for Railroads) to reduce settlement of transitional zone and horizontal displacement of abutment by constructing backfill before abutment. We expect that it has more economical and better performance which was validated by numerical analyses. First, transitional zone settlements and horizontal displacements of existing abutment were evaluated for various heights and ground conditions by using finite element analysis program. Then, numerical analyses of it under the same conditions were performed and its results were compared with existing abutment's ones. From the numerical analysis, we found that the responses(settlement and horizontal displacement) of transitional zone of the RAR is about 20% and 34% of one of existing abutment due to the effect of backfill stabilizing. We expected that the RAR having small foundations could be economic way to construct abutment with the control of responses such as, settlement, horizontal displacement, and earth pressure.

Change in Community Composition and Soil Carbon Stock Along Transitional Boundary in a Sub-Tropical Forest of Garhwal Himalaya

  • Kumar, Munesh;Kumar, Manish;Saleem, Sajid;Prasad, Sunil;Rajwar, G.S.
    • Journal of Forest and Environmental Science
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    • v.29 no.3
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    • pp.194-199
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    • 2013
  • The aim of the present study was to assess the effect of transitional boundary on community composition and soil carbon stock. Five vegetation types were recognized horizontally along the transitional strip based on the dominance of tree species i.e., Pure Anogeissus latifolia forest (P.AL), mixed Pinus roxburghii and Lannea coromandelica forest (M.PR&LC), pure Pinus roxburghii forest (P.PR), mixed Pinus roxburghii and Lannea coromandelica (M.PR&LC) and pure Anogeissus latifolia forest (P.AL). The results revealed that Anogeissus latifolia was reported dominant tree in the outer transitional boundaries of the forest, which reduced dominance of trees towards middle where Pinus roxburghii was found dominant. The soil carbon stock was reported higher in the Anogeissus latifolia dominant forest and reduced with the dominance of Pinus roxburghii in the middle site. Both the species are growing close to one another and competing for survival, but the aggressive nature of Anogeissus latifolia particular in this region may change new growth of Pinus roxburghii and will enhance soil carbon stock. But high anthropogenic pressure on Anogeissus latifolia tree species could be limited chance to further its flourish.

Diagnostic Strategy Using Barium Enema and Rectal Suction Biopsy with Acetylcholinesterase Histochemistry in Neonates with Suspious Hirschsprung's Disease (신생아 Hirschsprung's Disease에서 Barium Enema와 Acetylcholinesterase 조직화검사법을 이용한 진단적 접근)

  • Choi, Young-Il;Choi, Soon-Ok;Park, Woo-Hyun
    • Advances in pediatric surgery
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    • v.7 no.2
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    • pp.105-111
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    • 2001
  • To investigate the diagnostic accuracy and applicability of barium enema(BE) and rectal suction biopsy with acetyl cholinesterase(AChE) histochemistry in the diagnosis of neonatal Hirschsprung's disease(HD), we retrospectively reviewed the findings of BE and AChE staining in 96 neonates with suspected HD during a 10-year period from January 1991 to December 2000. Sixty-nine cases of HD(58 males and 11 females) and 27 cases of non-HD are included in this study. In regard to BE, HD was based on definite transitional zone, suspicious HD on reversed rectosigmoid index(RSI <1), and non-HD on normal RSI(RSI>1). The histochemical criterion used for the diagnosis of HD was that of Chow et al(1977), i.e., the presence of many coarse discrete cholinergic nerve fibers in the muscularis mucosae and in the immediately subjacent submucosa regardless of infiltration of cholinergic nerve fibers in the lamina propria. Of 66 neonates with HD who underwent BE, transitional zone was identified in 33 cases(50 %) and reversed RSI in 19 cases(21 %), microcolon in 4 cases and normal finding in 10 cases(15 %) while of 27 neonates with non-HD, there was normal finding in 16 cases and reversed RSI in 9 cases(41 %). Thus diagnostic accuracy based on transitional zone was 64 %. The positive predictive value of reversed RSI for the diagnosis of HD was 68 %. Of 42 neonates with HD who underwent AChE histochemistry, there were 41 AChE-positive reactions and one AChE-negative reaction in a neonate with total colonic aganglionosis, while of 27 cases of non-HD, there were one equivocal AChE-positive reaction and 26 AChE-negative reactions. Thus AChE histochemical study showed a 97 % diagnostic accuracy with a 98 % sensitivity and a 96 % specificity. In conclusion, we believe that BE is valuable as a first diagnostic step since about 80 % of neonates with HD show significant radiologic findings such as a transitional zone or reversed RSI. AChE histochemical study was a more reliable diagnos tic tool showing a 97 % diagnostic accuracy, and is part.

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Effect of Flare Angle in Counter-Rotating Swirler on Swirling Flow (동축 반전 스월러의 플레어 각도변화가 스월러 유동에 미치는 영향 연구)

  • Kim, Taek Hyun;Kim, Sung Don;Jin, Yu In;Min, Seong Ki
    • Journal of the Korean Society of Combustion
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    • v.21 no.1
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    • pp.31-37
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    • 2016
  • Swirler generates the overall swirling flow in the combustion chamber and this swirling flow governs the flame stability and enhances fuel atomization. This paper deals with the flare angle effects on flow streamlines, recirculation zone, Central Toroidal Recirculation Zone(CTRZ) and Corner Recirculation Zone(CRZ) in the model combustion chamber using counter-rotating swirler. 2D PIV system was employed to obtain the velocity components and test condition was obtained using Reynolds Analogy equivalent to air test. We observed transitional flow patterns of flare angle increased. The obtained results show that the flare angle controls the behavior of Recirculation zone, Central Toroidal Recirculation Zone and Corner Recirculation Zone.

Study on Laws Conerned With Environmental Management of the Coadtal Zone in Korea (우리 나라 연안환경보전 관련 법율 에 관한 연구)

  • 공경자
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.7 no.1
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    • pp.25-40
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    • 2001
  • The coastal waters and the adjacent coastal lands strongly influenced by each other and includes islands, transitional and intertidal ares, salt marshes wetlands and beaches. We focus on the coastal zone because of its unique geographical characteristics, Its ecological and economic importance, and the increasing pressures on its integrity. Our coastal zone have been controlled individually about 50 of a different kind of laws, as a result, to reach an individual purpose of the laws, people have developed the coastal zone without considering environmental condition, which brought about ecological destruction, pollution and devastation of the coastal areas. Finally, In 1999, the Coastal Management Act and the Wetlands Conservation Act were established and hereafter the environmental concern has been increased. They will be an important role to preserve our environment of coastal zone. Here I will examine the Laws concerned with environmental management of coastal zone and indicate immanent problems of it. So, I expect that problems will be improved one by one through this paper.

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Microanatomy and Histological Features of Central Myelin in the Root Exit Zone of Facial Nerve

  • Yee, Gi-Taek;Yoo, Chan-Jong;Han, Seong-Rok;Choi, Chan-Young
    • Journal of Korean Neurosurgical Society
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    • v.55 no.5
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    • pp.244-247
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    • 2014
  • Objective : The aim of this study was to evaluate the microanatomy and histological features of the central myelin in the root exit zone of facial nerve. Methods : Forty facial nerves with brain stem were obtained from 20 formalin fixed cadavers. Among them 17 facial nerves were ruined during preparation and 23 root entry zone (REZ) of facial nerves could be examined. The length of medial REZ, from detach point of facial nerve at the brain stem to transitional area, and the thickness of glial membrane of central myelin was measured. We cut brain stem along the facial nerve and made a tissue block of facial nerve REZ. Each tissue block was embedded with paraffin and serially sectioned. Slices were stained with hematoxylin and eosin (H&E), periodic acid-Schiff, and glial fibrillary acid protein. Microscopy was used to measure the extent of central myelin and thickness of outer glial membrane of central myelin. Thickness of glial membrane was examined at two different points, the thickest area of proximal and distal REZ. Results : Special stain with PAS and GFAP could be differentiated the central and peripheral myelin of facial nerve. The length of medial REZ was mean 2.6 mm (1.6-3.5 mm). The glial limiting membrane of brain stem is continued to the end of central myelin. We called it glial sheath of REZ. The thickness of glial sheath was mean $66.5{\mu}m(40-110{\mu}m$) at proximal REZ and $7.4{\mu}m(5-10{\mu}m$) at distal REZ. Conclusion : Medial REZ of facial nerve is mean 2.6 mm in length and covered by glial sheath continued from glial limiting membrane of brain stem. Glial sheath of central myelin tends to become thin toward transitional zone.