• Title/Summary/Keyword: connection design

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Retrospective study of conical connection dental implant (Ankylos dental Implant). (Conical connection 임프란트(Ankylos dental implant)에 대한 후향적 임상연구)

  • Yang, Byoung-Eun;Song, Sang-Hun;Shim, Hye-Won;Lee, Sang-Min;Kim, Seong-Gon
    • The Journal of the Korean dental association
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    • v.44 no.11 s.450
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    • pp.739-747
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    • 2006
  • Objectives. The standardization of connection between fixture and abutment has not been defined. The success of dental implants was not always depends on connection. However, the connection mechanism is one of the most important things for dental implant treatment success. Most implant systems are very comparable in their design and engineering. They share many common characteristics and have similar strengths and weaknesses. Their significant weaknesses are connection, microgap and the resulting micromovement allowing bacterial contamination and bone loss. In the present study, we investigated the clinical performance of Ankylos implant (conical connection implant) Patients and Methods. The clinical performance of conical connection implant was studied under well-controlled clinical conditions. A total of 133 conical connection implants were placed in 50 patients from April 2005 to March 2006. The mean follow-up loading period of implants which was considered successful was 220$\pm$29 days. We recorded the age, sex, installation site, reason of edentulous region, bone density of installation site, diameter and length of dental implants and periods from installation to uncovering surgery using patients medical chart. Results Four Ankylos implants were lost during pre-loading period. 129 implants provided excellent clinical performance during 220$\pm$29 days on an average. The short-term success rate of this conical connection implant system was 96.99%.

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Sway of semi-rigid steel frames - Part 1: Regular frames

  • Ashraf, M.;Nethercot, D.A.;Ahmed, B.
    • Steel and Composite Structures
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    • v.4 no.5
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    • pp.403-418
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    • 2004
  • Lateral sway is most likely to control the design of semi-rigid steel frames where the frame arrangements do not include any form of bracing. This paper investigates the sway behaviour of semi-rigid regular steel frames i.e., frames having the same arrangement of beam and column sections at all levels, and hence proposes some design charts for the prediction of sway that eliminate the need for doing any numerical modelling. Schueller's equation has also been modified to incorporate connection flexibility in addition to its original rigid frame considerations. All the proposed methods have been validated using results obtained from numerical analysis.

A Design of Routing Path and Wavelength Assignment with Fairness in WDM Optical Transport Network (WDM 광전달망에서 공정성을 갖는 경로설계 및 파장할당)

  • 박구현;우재현
    • Journal of the Korean Operations Research and Management Science Society
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    • v.22 no.4
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    • pp.17-35
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    • 1997
  • This paper considers the efficient design of routing path and wavelength assignment in the single-hop WDM optical transport networks. The connection demands between node-pairs are given and a connection between a pair of nodes must be made by only one lightpath. It is assumed that no wavelength conversion is allowed and the physical topology of the network and the number of available wavelengths of a physical link are also given. This paper proposes the method to route a path and assign a wavelength to the path, which guarantees fairness to every node pair. In order to guarantee fairness and maximize connections, an optimization model is established, which successively maximizes minimum connection ratio to the demand of each node pair. A heuristic algorithm with polynomial iterations is developed for the problem since the problem is NP-hard. The heuristic algorithm is implemented and applied to the networks with real problem sizes. The results of the application are compared with GAMS/OSL.

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A Study for Structural Capacity Evaluation of Embedded Steel Plate Connected with Prestressed Concrete Beam to Build Large Space Educational Facilities (대공간 교육시설 축조를 위한 프리스트레스트 보에 사용되는 접합 강재의 성능평가에 대한 연구)

  • Lee, Kyoung-Hun
    • The Journal of Sustainable Design and Educational Environment Research
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    • v.10 no.2
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    • pp.1-7
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    • 2011
  • An experimental study to evaluate structural capacity of an embedded plate connected with prestressed concrete beam was performed. Embedded steel plates and prestressed concrete beam were connected with stud-bolts at the ends of concrete beam specimens. About 1,000 kN concentrated load was applied at 450mm away from the end of beam specimen. A 3,000 kN capacity static Oil-jack was used to direct concentrated load. The maximum strain of stud-bolt recorded $90{\times}10^{-6}$(mm/mm) and wide width cracks were not founded. Any falling failures of concrete and large deformations were not founded either between steel plate and prestressed concrete specimen. As a result, construction performance can be improved using this embedded steel plate connection system apply to large space educational facilities.

Identification of Connections of Vibration Systems Using Substructural Sensitivity Analysis (부분구조 기반 민감도 해석을 이용한 진동시스템의 연결부 특성 추정)

  • 서세영;김도연;김찬묵;이두호
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2001.05a
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    • pp.786-792
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    • 2001
  • In this paper, the identification of connections for a vibration system has been presented using FRF-based substructural sensitivity analysis. The substructural design sensitivity formula is derived and plugged into a commercial optimization program, MATLAB, to identify connection stiffness of an air-conditioner system of passenger car. The air-conditioner system, composed of a compressor and a bracket is analyzed by using FRF-based substructural(FBS) method. To obtain the FRFs, FE model is built for the bracket, and the impact hammer test is performed for the compressor. Obtained FRFs are combined to calculate the reaction force at the connection point and the system response. Connection element properties are determined by minimizing the difference between a target FRF and calculated one. It is shown that the proposed identification method is effective even for a real problem.

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Design of Bandpass Filters using Microstrip Line PBG (마이크로스트립 PBG를 이용한 대역통과 여파기 설계)

  • Lee, Chang-On;Kim, Sang-Tae;Shin, Chull-Chai
    • Proceedings of the Korea Electromagnetic Engineering Society Conference
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    • 2003.11a
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    • pp.361-365
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    • 2003
  • In this paper, we proposed the effective serial connection methodology of PBG resonator with defect mode. We use the big difference of impedance ratio in connection region, for example dual PBG, for serial connection. This method reduces the PBG cells and is able to control the pole of bandpass filters. This result in flexibility in design of bandpass filter. Our PBG bandpass filter is modeled by using the ideal transmission line model. This model is very easy, fast, and effective for PBG structure.

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A Study on the Improvement direction of Interior Architecture connection Qualification (실내건축 관련 자격검정의 개선방향에 관한 연구)

  • 윤갑근;김양지;최승희
    • Korean Institute of Interior Design Journal
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    • no.41
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    • pp.3-10
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    • 2003
  • The purpose of this study was to analyze the problems of the existing interior architecture connection qualification and propose the desirable direction of development. To do this, this study suggested basic materials for the connection between the qualification for interior architecture and practical business, and for an efficient qualification. For methods, first, this study analyzed the flow and the ratio of successful applicants of the qualification of interior architecture in order to consider problems. Secondly, this study grasped the composition of examination. Thirdly, this study examined the changes of the questions in standards. Fourth, this study investigated overseas examples. In addition, this study conducted a questionnaire for professionals engaging in practical business in order to contribute for establishing the desirable frame of qualification of interior architecture through the analysis and comparison of the results.

Developments in composite construction and cellular beams

  • Lawson, R.M.;Hicks, S.J.
    • Steel and Composite Structures
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    • v.5 no.2_3
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    • pp.193-202
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    • 2005
  • This paper describes recent developments in composite construction and their effect on codified design procedures in the UK. Areas of particular interest include: rules on shear connection, design of beams with web openings, serviceability limits, such as floor vibrations, and fire safe design. The design of cellular beams with regular circular openings now includes generalized rules for web-post buckling, and for the development of in-plane moment in the web-post for asymmetric sections. Closed solutions for the maximum shear force due to limits on web-post bending or buckling are presented. The fire resistance of cellular beams is also dependent on the temperature of the web-post, and for closely spaced openings. It is necessary to increase the thickness of fire protection to the web. For serviceability design of beams, deflection limits and natural frequency and response factor for vibration are presented. It may be necessary to use stricter limits for certain applications.

A Collaborative Engineering Based System Supporting Product Development Process (협업공학 기반의 제품개발 지원 시스템)

  • Park H. S.;Choi H. W.;Lee G. B.
    • Korean Journal of Computational Design and Engineering
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    • v.9 no.4
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    • pp.387-396
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    • 2004
  • In order to keep and increase a competitive potential, industrial enterprises have to reduce their costs for product development as well as shorten lead time in product development processes. Moreover they have to respond to market factors and conditions such as increasing demands for functionality and individuality of products, short product life cycles, high pressure on prices and time to market. The improved functional requirement in connection with high time and cost pressure lead to high risk in product development. Technological fine improvements in connection with high time and cost pressure lead to high development risk. To cope with these challenges many enterprises have to collaborate globally. The collaborative engineering in product development is aimed to create distributed collaborative corporations and to facilitate the management of design conflicts. This paper provides a methodology for analyzing collaborative design process as well as the tools and the framework to support collaborative product development. The methodology can identify the interdependences among design tasks and teams. The tools and framework are implemented to facilitate the management of product development process.

A Study On Optimum Reliability of Rigid Connection in Steel Structures (최적신뢰성에 의한 강구조물의 강접합부 연구)

  • Jung, Chul-Won;Yu, Han-Shin
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.5 no.4
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    • pp.177-184
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    • 2001
  • In this study, three most distinct types of general rigid connections are included in the modelling, with is implemented into a computer code. The cost, functions of connections are constructed by using the estimated unit cost of bolting, welding and connection-steel elements incorporating all the effect of materials, labor, and fabrication work. Bused on the recent developments of the reliability-based structural analysis and design as well as the extending knowledge on the probabilistic characteristics of load and resistances, the probability based design criteria have been successfully developed for many standards. Since the probabilistic characteristics depend highly on the local load and resistances, it is recognized to develop the design criterion compatible with domestic requirements. The existing optimum design methods, which are generally based on the structural theory and certain engineering experience, do not realistically consider the uncertainties of load and resistances and the basic reliability concepts.

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