• Title/Summary/Keyword: Anchorage area

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Indirect palatal skeletal anchorage (PSA) for treatment of skeletal Class I bialveolar protrusion (Indirect palatal skeletal anchorage (PSA)를 이용한 골격성 I급 양악 치성 전돌 환자의 치험례)

  • Chae, Jong-Moon
    • The korean journal of orthodontics
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    • v.34 no.5 s.106
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    • pp.458-464
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    • 2004
  • Anchorage plays an important role in orthodontic treatment especially in the maxillary arch. In spite of many efforts for anchorage control. it was difficult for clinicians to predict the result of treatment because most of the treatment necessitated an absolute compliance of patients, But recently, skeletal anchorage has been used widely because it does not necessitate patient compliance but produces absolute anchorage. In addition titanium miniscrews have several advantages such as ease of insertion and removal. possible immediate leading and use in limited implantation spaces. In this case, a skeletal Class I bialveolar protrusion Patient was treated with standard edgewise mechanics using indirect active P.S.A. (palatal skeletal anchorage). The miniscrews in the paramedian area of the hard palate provided anchorage for retraction of the upper anterior teeth and remained firm and stable throughout treatment This indicates that the PSA can be used to reinforce anchorage for orthodontic treatment in the maxillary arch Consequently, this new approach can help effective tooth movement without patient compliance, when used with various transpalatal arch systems.

Evaluate Anchorage Strength of High Relative Rib Area Bars Using Hook Test Specimens (갈고리 시험체를 이용한 높은마디면적 철근의 정착성능)

  • Seo Dong Min;Hong Gi Suop;Choi Dong Uk;Choi Oan Chul
    • Proceedings of the Korea Concrete Institute Conference
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    • 2005.05a
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    • pp.327-330
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    • 2005
  • Bond failure of reinforcing bar generally take place by splitting of the concrete cover as bond force between concrete and reinforcing bars exceeds the confinement of the concrete cover and reinforcement. However, the confinement force in practice has a limitation. Thus, the only variable is the bearing area corresponding to the change of bond force. In this study, to the evaluate anchorage strength of high relative rib area bars, hook bond test specimens are tested and the results are discussed. Higher rib height bars when bars are confined showed higher anchorage strength than lower rib higher bars.

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A Study on the Designation of MIPO Emergency Ancho (미포항 비상정박지 지정에 관한 연구)

  • Lee, Yun-Sok;Kim, Jong-Sung;Park, Jun-Mo;Yun, Gwi-Ho
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.18 no.4
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    • pp.316-322
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    • 2012
  • In the port of Ulsan with the area of harbor limit of $83km^2$, 25,432 vessels have been entering annually and only 35 vessels can anchor simultaneously at the anchorage. The area of harbor limit of Ulsan constitutes just 65 percent compared to $127.5km^2$ which is an average of main ports in Korea. In this regard, the port of Ulsan needs to expand the area of anchorages inevitably for enhancing the efficiency of port operation. To select the best anchorage area in Mipo harbor with the introduction of a concept of emergency anchorage, this study analyzed the safety of navigation and anchorage, and safety management, etc. in the prospected anchorage on the basis of the marine traffic survey observing traffic density. Furthermore, after drawing preliminary and final schemes through gathering the opinions from maritime users, safety management organizations and academic experts group, the best arrangement of emergency anchorage has been selected through the conference of interested parties. Then, the final scheme was also verified through figuring out the marine traffic system and carrying out the ship handling simulation.

The skeletal cortical anchorage using titanium microscrew implants (Titanium microscrew implant를 이용한 skeletal cortical anchorage)

  • Park, Hyo-Sang
    • The korean journal of orthodontics
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    • v.29 no.6 s.77
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    • pp.699-706
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    • 1999
  • Anchorage plays an important role in orthodontic treatment. Endosseous implants may be considered adequate firm anchorage. However, clinicians have hesitated to use endosseous implants as orthodontic anchorage because of limited implantation space, high cost, and long waiting period before osseointegration occurs. Recently, some clinicians have tried to use titanium miniscrews and microscrews in treatment due to their many advantages such as ease of insertion and removal, low cost, immediate loading, and the ability to place microscrews in any area of alveolar bone. The author treated a case with skeletal cortical anchorage using titanium microscrew implants. During six months of orthodontic force application from skeletal cortical anchorage, the author could get 4 mm bodily retraction and intrusion of upper anterior teeth. The most outstanding result was a 1.5 mm posterior refraction of the upper posterior teeth. The titanium microscrew implants had remained firm and stable throughout treatment. These results indicate that skeletal cortical anchorage might be a very good option.

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Stress Properties for Anchorage Zone of Cable Stayed Bridge Prestress Concrete (프리스트레스트 콘크리트 사장교 정착부의 응력특성)

  • 조병완;변윤주;최준혁;태기호
    • Proceedings of the Korea Concrete Institute Conference
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    • 2002.05a
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    • pp.531-536
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    • 2002
  • The design of anchorage zone in prestressed concrete cable stayed bridges is very important area due to the more accurate analysis is needed to estimate the behavior. In the study, since the cable anchorage zone in the prestressed concrete cable-stayed bridge is subject to a large amount of concentrated tendon forces, it shows very complicated stress distributions and causes a serious local cracks. Accordingly, It is necessary to investigate the parameters of affecting the stress distribution, such as the cable inclination, the position of anchor plate, the modeling method and the three dimensional effect. The tensile stress distribution of anchorage zone is compared to the actual design condition by varing the stiffness of spring element in the local modeling and an appropriate position of anchor plate is determined. These results would be elementary data to the stress state of anchorage zone and more efficient design.

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Improvement Plan on Operation of O-2 Anchorage at the Busan North Port (부산 북항 O-2 정박지의 운영개선 방안)

  • Song, Gye-Eui
    • Journal of Korea Port Economic Association
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    • v.25 no.1
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    • pp.29-46
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    • 2009
  • According to construction work of No. 2 Lotte world, the alternative pier is under construction in Dongsam-dong Yeongdo-gu to accommodate small boats. As a result of that, in order to procure route of small boats passage,0-2 Anchorage used to bunkering or waiting for berth should be reduced, 220m. It is expected that the risk of passage and congestion around the anchorage could be increased because of the traffic of small boat using the alternative pier. Therefore, it is needed to enlarge the O-2 Anchorage 250m toward to inner breakwater. According to result of analyzing traffic circumstance and weather condition of anchorage near the Busan inner fairway, and to procure of alternative anchorage in order to resolve the problem caused by reduction of O-2 Anchorage, no problems incurred. In conclusion, reduction & enlargement of area of new O-2 Anchorage is expected to resolving of congestion & reducing of risk of traffic at O-2 Anchorage, and to operating O-2 Anchorage, efficiently.

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A Study on Stress Properties for Cable Anchorage zone of Cable Stayed Prestressed Concrete Box Girder (케이블로 지지된 프리스트레스트 콘크리트 박스거더 정착부의 응력특성에 관한 연구)

  • Tae, Ghi-Ho;Kim, Doo-Hwan;Byun, Yun-Joo;Song, Kwan Kwon
    • Journal of the Korean Society of Safety
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    • v.27 no.6
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    • pp.84-92
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    • 2012
  • Anchorage zone in prestressed concrete cable stayed bridges is very important area due to the more accurate analysis is needed to estimate the behavior. In the study, since the cable anchorage zone in the prestressed concrete cable-stayed bridge is subject to a large amount of concentrated tendon forces, it shows very complicated stress distributions and causes a serious local cracks. Accordingly, It is necessary to investigate the parameters of affecting the stress properties, such as the cable inclination, the position of anchor plate, the modeling method and the three dimensional effect. The tensile stress distribution of anchorage zone is compared to the actual design condition by varing the stiffness of spring element in the local modeling and an appropriate position of anchor plate is determined. These results would be elementary data to the stress state of anchorage zone and more efficient design.

Mandibular Posterior Rehabilitation Case after Occlusal Plane Correction using Micro-Implant Anchorage (Micro-Implant를 이용한 교정치료로 교합평면 개선 후 하악 구치부 수복증례)

  • Park, Ju-Mi
    • Journal of Dental Rehabilitation and Applied Science
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    • v.20 no.2
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    • pp.143-150
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    • 2004
  • Endosseous implants have been used to provide anchorage control in orthodontic treatment without the need for special patient cooperation. However these implants have limitation like space requirement, cost, equipments. Recently titanium micro-implant for orthodontic anchorage was introduced. Micro-implants are small enough to place in any area of the alveolar bone, easy to implant and remove, and inexpensive. In addition, orthodontic force application can begin almost immediately after implantation. The mandibular first, maxillary first, mandibula second, and maxillary second molars were the four most commonly missing teeth in adult sample. In case of posterior molar teeth missing, deflective contacts in any position, over time, has produced pathologic change of occlusal scheme because of extrusion of opposing teeth. This case had interocclusal space deficiency by mandibular right molars missing over time. The micro-implants had been used for intrusion of maxillary right molars for interocclusal space. The micro-implant would be absolute anchorage for orthodontic movement. Therefore, the micro-implant would be effective method for correction of occlusal plane.

The Load Transfer Performance of Post-tension Anchorage with 2,400 MPa Strands (2,400 MPa 강연선용 포스트텐션 정착구의 하중전달성능)

  • Kim, Sun-Woo;Lho, Byeong-Cheol;Lim, Jung-Hoon
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.22 no.6
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    • pp.63-71
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    • 2018
  • Strands with ultimate strength of 2,400 MPa was developed and applied in the KCI Code and the KS standard. A high-strength prestressed strand to be applied to a structure, a suitable anchorage system should be used together. Recently, a post tension anchorage for 2,400 MPa strands was developed. but there is not much research on performance evaluation. Therefore, in this study, structural analysis of local zone with 9 strands, 15 strands, and 19 strands anchorage were investigated respectively, which are most widely used for post tensioning anchorages with 2,400 MPa strands, according to PTI anchorage zone design method, and Load transfer performance from ETAG013 and/or KCI-PS101 was evaluated. Furthermore, the adequacy of the test was also analyzed by nonlinear numerical analysis. As results, the anchorages with 2,400 MPa strands satisfied the structural performance of the local area and satisfied the load transfer performance condition.

A Study on Design of Emergency Anchorage at Adjacent Waters of Wan-do Port (완도항 인근 수역 피항 정박지 지정 검토 연구)

  • Im, Nam-Kyun;Kim, Chol-Seong;Yang, Hyoung-Seon;Lee, Kyoung-Woo
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.14 no.1
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    • pp.65-69
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    • 2008
  • Now it is said that the insufficency of the designated anchorage for ships in approaching waters of Wan-do port is the one of reasons for marine safety accidents, when vessels encounter rough weather near the port. This research examined geographical feature in approaching areas of Wan-do port and suggested appropriate weather anchorage. The situations of fishing nets areas were investigated Marine vessel traffic flow was also examined. Through these research the optimal anchorage was suggested in the approaching waters of Wan-do port.

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