• Title/Summary/Keyword: Structure restoration

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3 DOFs bridge-vessel collision model considering with rotation behaviors of the vessel (선박의 회전거동을 고려한 3자유도 충돌모델)

  • Lee, Gye-Hee;Lee, Seong-Lo
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2008.04a
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    • pp.380-385
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    • 2008
  • 3 DOFs model for the collision analysis of a bridge super-structure and a super-structure of the navigating vessels were proposed and analyzed. The collision event between the super-structure of vessel and the super-structure of bridge are different from the normal collision event that collided at sub-structure of bridge. Because of its moment arm, the stability force of vessel could affect to the collision behaviors. To consider this effect, 3 DOFs model including two translation DOFs and one rotational DOF were introduced. The restoration forces of the collision system were considered as nonlinear springs. The equations of motion were derived if form of differential equations and numerically solved by 4th order Runge-Kutta method. The accuracy and the feasibility of this model were verified by the numerical example with parameter of moment arm length.

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Engineering Characteristic of High Density Expansion Materials for Structure Restoration Technology (기초침하복원을 위한 급속 팽창재료의 공학적 특성에 관한 연구)

  • Shin, Eun-Chul;Cha, Yong-In
    • Journal of the Korean Geosynthetics Society
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    • v.7 no.2
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    • pp.1-5
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    • 2008
  • The differential settlement on ordinary concrete buildings and paved roads are often occurred and which caused the failure of structure. The grouting method can be used for correcting the settlement of the structure. However, the grouting method has a disadvantage like that it takes a long time period to get a desired strength, and it is not a continuous in the phase of reinforced effect. In this paper, as an injecting material called GPCON to complement disadvantage, it is estimated about the characteristic that has a high-density expansion. With the changing of ground conditions and amount of injection, the change of physical strength on compression, the stability against chemical material are studied through the filming of SEM. The physical strength with compression is developed to high strength due to mixing with other material. It is not react with most of the material on chemical conditions except the component of alcohol. Through the SEM test. it is confirmed that the strength of material was increased as formation is being densified.

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Habitat Characteristics and Vegetation Structure of the Evergreen Fern in Jejudo, Korea (제주도의 상록양치식물 자생지 환경특성 및 식생구조에 관한 연구)

  • Bang, Kwang Ja;Kim, Kwang-Du;Kang, Hyun-Kyung;Ju, Jin Hee
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.7 no.3
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    • pp.64-72
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    • 2004
  • The research was carried out to define the environmental characteristics and vegetation structure of the evergreen fern habitat in Jejudo. The growth conditions of evergreen fern in various habitats was surveyed, including topographical features, vegetation structure, air temperature, humidity, intensity of light, water content and organic matter content in the soil. In the direction of the native habitat, 70% of research area was located in the southeast-facing slopes, 30% was located in southern slopes. The gradient ranged from $0^{\circ}$ to $30^{\circ}$. Temperature ranged from $16^{\circ}C$ to $28^{\circ}C$, and $22.3^{\circ}C$ was the average. Humidity ranged from 20 to 68%, and 36% was the average. In the native habitat, the highest light intensities reached 60,000 to 80,0001ux, but in general ranged from 300 to 40001ux. Water content in the soil ranged from 32% to 59%, organic matter content ranged from 8 to 13%. Within a unit of 25$m^2$, there were tall-tree layer such as Quercus galuca and Castanopsis cuspidata with a covering of rate 40~80%, a sub-tall-tree layer such as Camellia japonica, Staphylea bumalda and Sambucus williamsii with the covering rate of 3~5%, a shrub layer with the covering rate of 5~20%, and a grass layer with the covering rate of 40~95%. This research provides the basic data about the native habitat environment of the evergreen fern plant. Continuous monitoring and accumulation of data is necessary for the use of evergreen fern as vegetation materials.

Studies on the Restoration of Ancient Bridge Setakarahashi -Conservation and Display for Large Size Waterlogged Wood- (고대 세다당교의 보존처리 - 대형출토목재의 보존과 전시 -)

  • NAKAGAWA, Masato
    • Journal of Conservation Science
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    • v.5 no.2 s.6
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    • pp.51-56
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    • 1996
  • This paper deals with the restoration of ancient wooden bridge foundation which excavated in Seta river Shiga Prefecture, Japan. Shiga Archeological Research started a marine archeological investigation of the bridge foundation in 1987. The bridge foundation stricture excavated and have since then recovered about a lots of woods and another materials. The bridge foundation structure constructed log, timbers and stones. The species of those waterlogged wood were identified as two types, hardwood and softwood. Hardwood(log : Cyclobalanopsis) was used for below foundation and softwood (timber' Chamaecyparis obtusa Endl. Cupreessaceae) was used for base structure. One of those timber sample dated by dendrochronology, we asked Dr. Misutani*. The softwood gave a felling date of 567 A.D. In result, the ancient Seta bridge foundation structure had constructed between Asuka and Nara period. We healed the news that ancient bridge foundation excavated at Woljyongyo site in Kyongju, Korea 1987. The bridge foundation Setakarahashi is similar in plane and structure to Woljyongyo structures. The Woljyongyo site report had be of value for reference. We had planning to restore those woods. Hardwood log was got serious damage. The water content varies from 400 to $600\%$. The other timbers water content varies about $200\%$. In the Shiga Center for Archaeological Operations and the Azuchi Castle Archaeological Museum, we set up the PEG impregnation tank. Those wooden objects treated by PEG method. PEG with a molecular weight of 4000. The treatment results may be considered satisfactory. The ancient wooden Seta bridge was reconstructed in Biwako Museum which established in Oct. 1996. We must take care of indoor exhibition environments. (*Nara National Cultual Properties Research Institute).

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Indoor Passage Tracking based Transformed Generic Model (일반화된 모델의 변형에 의한 실내 통로공간 추적)

  • Lee, Seo-Jin;Nam, Yang-Hee
    • The Journal of the Korea Contents Association
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    • v.10 no.4
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    • pp.66-75
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    • 2010
  • In Augmented Reality, it needs restoration and tracking of a real-time scene structure for the augmented 3D model from input video or images. Most of the previous approaches construct accurate 3D models in advance and try to fit them in real-time. However, it is difficult to measure 3D model accurately and requires long pre-processing time to construct exact 3D model specifically. In this research, we suggest a real-time scene structure analysis method for the wide indoor mobile augmented reality, using only generic models without exact pre-constructed models. Our approach reduces cost and time by removing exact modeling process and demonstrates the method for restoration and tracking of the indoor repetitive scene structure such as corridors and stairways in different scales and details.

Piecewise Image Denoising with Multi-scale Block Region Detector based on Quadtree Structure (쿼드트리 기반의 다중 스케일 블록 영역 검출기를 통한 구간적 영상 잡음 제거 기법)

  • Lee, Jeehyun;Jeong, Jechang
    • Journal of Broadcast Engineering
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    • v.20 no.4
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    • pp.521-532
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    • 2015
  • This paper presents a piecewise image denoising with multi-scale block region detector based on quadtree structure for effective image restoration. Proposed piecewise image denoising method suggests multi-scale block region detector (MBRD) by dividing whole pixels of a noisy image into three parts, with regional characteristics: strong variation region, weak variation region, and flat region. These regions are classified according to total pixels variation between multi-scale blocks and are applied principal component analysis with local pixel grouping, bilateral filtering, and structure-preserving image decomposition operator called relative total variation. The performance of proposed method is evaluated by Experimental results. we can observe that region detection results generated by the detector seems to be well classified along the characteristics of regions. In addition, the piecewise image denoising provides the positive gain with regard to PSNR performance. In the visual evaluation, details and edges are preserved efficiently over the each region; therefore, the proposed method effectively reduces the noise and it proves that it improves the performance of denoising by the restoration process according to the region characteristics.

The Planting Models of Carpinus turczaninowii Community by the Plant Community Structure Analysis in Badahyanggi Arboretum - Case Study of Daebu-Yeongheung Islands - (군집구조분석을 통한 바다향기수목원 소사나무림 식재모델 연구 - 대부도 및 영흥도를 대상으로 -)

  • Kim, Yong-Hoon;Kwon, Oh-Jung;Ban, Su-Hong;Oh, Choong-Hyeon
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.23 no.4
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    • pp.31-45
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    • 2020
  • This study suggested the planting models of Carpinus turczaninowii community to make in Badahyanggi Arboretum and was carried out to the structure of C. turczaninowii commnity in Daebu-Yeongheung Islands. In order to identify the current ecological environment, this study set to 13 plots(i.e. 100㎡) for analysing detailed structure of plant communities. The research methodology was qualitative analysis. It used TWINSPAN, PCA and Indicator Species Analysis tools which are performed well in several comparisons of classification techniques and one of the ordination techniques showed that the plant communities. The results were classified into 3 communities that C. turczaninowii-Pinus densiflora community(I), C. turczaninowii-Quercus serrata community(II) and C. turczaninowii-Platycarya strobilacea community(III). In all of communities, C. turczaninowii was dominant species in canopy layer and understory layer, the degree of closure was high. Proposed the planting models that are I~II communities based on planting status in Badahyanggi Arboretum(Island Plant Botanical Garden), the structure of plant communities, indicator species and individual distribution by DBH classes. Also, The multi-layer planting plans are necessary, such as P. strobilacea, Lindera erythrocarpa, Viburnum carlesii, V. dilatatum, Ligustrum obtusifolium, Zanthoxylum schinifolium and so on.

A Study on the Changing Connectivity of Pedestrain Network Using Space Syntax - Focussing on Restoration of Cheonggyecheon - (Spacee Syntax를 이용한 보행자 네트워크 연결성 변화연구 - 청계천복원사업을 중심으로 -)

  • Kim, Tae-Ho;Park, Ju-Won;Ko, Young-Sun;Park, Je-Jin
    • International Journal of Highway Engineering
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    • v.11 no.2
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    • pp.55-66
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    • 2009
  • This study examines the consequent impact which Cheonggyechoen restoration project of Seoul makes on pedestrian network structure around the inner city, especially in terms of sustainable developments and the city's balanced development. It identifies variation of Global Integration and Local Integration of the pedestrian networks which is compared by before and after conditions with east-west and south-north walking axis by using Space Syntax. The results show respectively different set of Global and Local Integration. First, Global Integration shows high performance along the east-west axis, while pedestrian spatial networking is balancing through Donhwamunno and Samillo. Second, Local Integration illustrates both performance along both the east-west axis and the south-north axis after restoration of network. It is primarily concentrated in Taepyeongno$\sim$Samillo section(business and commercial-centered) before the restoration. In addition, total integration is holistically improved while the networking in Samillo$\sim$Baeogaegil section(the instrument shopping streets) if almost same as one another Moreover, in Baeogaegil$\sim$Dongdaemun Stadium section(market-centered), the connectivity of Cheonggyechoenro is improved after the restoration. All in all, Cheonggyechoen restoration project of Seoul allows traffics to be equally accessible from the east-west axis and the south-north axis and contributes to the connectivity improvement of the east-west axis as well as the south-north axis.

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Three key factors for successful esthetic anterior implant restoration (성공적인 전치부 심미 임플란트를 위한 3가지 요소)

  • Lim, Pil
    • Journal of the Korean Academy of Esthetic Dentistry
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    • v.25 no.1
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    • pp.35-49
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    • 2016
  • With the increasing demand for aesthetic implant dentistry, the importance of implant restoration is emphasized not only in the functional aspect but also in the aesthetic aspect. The aesthetic restoration of dental implants in the anterior maxilla is a challenge for clinicians because it requires proper harmony in three following conditions; reconstruction of hard tissue, soft tissue, and aesthetic prosthesis. The soft tissue aesthetics are dependent upon the condition of the supporting hard tissue because the osseous structure provides a framework for the development of a healthy and aesthetic soft tissue interface. Therefore, the augmentation of hard tissue is a first step and especially, optimal 3-dimensional position of implant is the most important factor in aesthetic implant restoration. The management of soft tissue is a second step, and the final step is a restoration of harmonic prosthesis using provisional restoration with proper emergence profile. This clinical report describes the procedure of bone augmentation in labial dehiscence defect, Vascularized Interpositional Periosteal-Connective Tissue (VIP-CT) flap for aesthetic anterior soft tissue, and the importance of provisional restoration and impression taking stage with customized impression coping.

- Aesthetic Restoration of the Gingival Recession with All-ceramic Partial Crown - (전치부 ALL-CERAMIC PARTIAL CROWN 의 임상)

  • Do, Hyang-Ju;Im, Ui-Bin;O, Ji-Yeon;Lee, Jong-Yeop
    • Journal of the Korean Academy of Esthetic Dentistry
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    • v.11 no.1
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    • pp.11-15
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    • 2002
  • The black triangle is a common clinical finding in aged people with gingival recessions. Among other prosthetic treatment molalities such as composite resin filling and laminate venners, the all ceramic restoration procedure can lead to most successful result. With improved bonding strength and ceramic properties, the tooth preparation design for all-ceramic crown can be modified to minimize the reduction of sound tooth structure without loosing properties of conventional preparation design. Case selection is an important factor in acheiving succesful prosthesis. In this case report, the leucite reinforced pressable ceramic, $Authentic^{TM}$ [Ceramay, Germany] was used to fabricate the prosthesis.

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