• Title/Summary/Keyword: restoring

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Experimental study on the seismic performance of concrete filled steel tubular laced columns

  • Huang, Zhi;Jiang, Li-Zhong;Chen, Y. Frank;Luo, Yao;Zhou, Wang-Bao
    • Steel and Composite Structures
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    • v.26 no.6
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    • pp.719-731
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    • 2018
  • Concrete filled steel tubular (CFST) laced columns have been widely used in high rise buildings in China. Compared to solid-web columns, this type of columns has a larger cross-section with less weight. In this paper, four concrete filled steel tubular laced columns consisting of 4 main steel-concrete tubes were tested under cyclic loading. Hysteresis and failure mechanisms were studied based on the results from the lateral cyclic loading tests. The influence of each design parameter on restoring forces was investigated, including axial compression ratio, slenderness ratio, and the size of lacing tubes. The test results show that all specimens fail in compression-bending-shear and/or compression-bending mode. Overall, the hysteresis curves appear in a full bow shape, indicating that the laced columns have a good seismic performance. The bearing capacity of the columns decreases with the increasing slenderness ratio, while increases with an increasing axial compression ratio. For the columns with a smaller axial compression ratio (< 0.3), their ductility is increased. Furthermore, with the increasing slenderness ratio, the yield displacement increases, the bending failure characteristic is more obvious, and the hysteretic loops become stouter. The results obtained from the numerical analyses were compared with the experimental results. It was found that the numerical analysis results agree well with the experimental results.

Repair of seismically damaged RC bridge bent with ductile steel bracing

  • Bazaez, Ramiro;Dusicka, Peter
    • Steel and Composite Structures
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    • v.26 no.6
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    • pp.745-757
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    • 2018
  • The inclusion of a ductile steel bracing as means of repairing an earthquake-damaged bridge bent is evaluated and experimentally assessed for the purposes of restoring the damaged bent's strength and stiffness and further improving the energy dissipation capacity. The study is focused on substandard reinforced concrete multi-column bridge bents constructed in the 1950 to mid-1970 in the United States. These types of bents have numerous deficiencies making them susceptible to seismic damage. Large-scale experiments were used on a two-column reinforced concrete bent to impose considerable damage of the bent through increasing amplitude cyclic deformations. The damaged bent was then repaired by installing a ductile fuse steel brace in the form of a buckling-restrained brace in a diagonal configuration between the columns and using post-tensioned rods to strengthen the cap beam. The brace was secured to the bent using steel gusset plate brackets and post-installed adhesive anchors. The repaired bent was then subjected to increasing amplitude cyclic deformations to reassess the bent performance. A subassemblage test of a nominally identical steel brace was also conducted in an effort to quantify and isolate the ductile fuse behavior. The experimental data from these large-scale experiments were analyzed in terms of the hysteretic response, observed damage, internal member loads, as well as the overall stiffness and energy dissipation characteristics. The results of this study demonstrated the effectiveness of utilizing ductile steel bracing for restoring the bent and preventing further damage to the columns and cap beams while also improving the stiffness and energy dissipation characteristics.

Possible Application of Animal Reproductive Researches to the Restoration of Endangered and/or Extinct Wild Animals - Review -

  • Fujihara, N.;Xi, Y.M.
    • Asian-Australasian Journal of Animal Sciences
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    • v.13 no.7
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    • pp.1026-1034
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    • 2000
  • As described here, most recently developed methods for improving reproduction performance of domesticated animals such as cattle, swine and chicken have been considered to be also usable for restoring some sorts of endangered and/or extinct wild animals in the very near future. Especially, the techniques for in vitro storage of gametes obtained from dead animals shortly after the death, probably 24 h following the sacrifice are also available for obtaining some of experimental specimens. In case of the endangered animals, nobody will be allowed to use any tissues from the living animals, therefore, e.g., the use of skin tissues from these bodies is another possibility of restoring the living animals. Regarding the use of skin tissues, the most highly usable tools must be the cloning techniques for reviving rare cells from the living body. Most possible techniques for cloning cells is nuclear transfer from rare species to highly relative species, and this is the case of germ cells, e.g., primordial germ cells (PGCs) of avian species. One of the possibilities is the nuclear transfer of Crested Ibis (Nipponia nippon) to the PGCs of chicken, resulting in the PGCs with transferred nucleus from the ibis. In mammalian species, the same procedure as in the case of birds would be successful, e.g., the removed nucleus from Giant Pandas will be transferred to the cell, such as somatic cells or germ cells from black bears or lesser pandas, leading to the production of transnucleared cells in the body of female black bears. These two cases are most promising techniques for reviving endangered animals in the world, particularly in Asian countries, mainly in China. As a conclusion, possible production of cloned animals carrying transnucleared cells from endangered animals, such as Giant Pandas and Crested Ibis, may be reproduced gradually in the near future. Scientists are, therefore, required to convert the paradigm from domestic animals to wild animals, including endangered and/or extinct animals on the earth.

Effect of Exercise Training following Hypokinesia on the Length and Circumference of Atrophied Soleus and Plantaris Muscle in Rats (활동저하후 회복기의 운동훈련이 쥐의 위축근의 길이와 둘레에 미치는 영향)

  • 최명애;안숙희
    • Journal of Korean Academy of Nursing
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    • v.22 no.3
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    • pp.325-336
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    • 1992
  • The purpose of this study was to determine the effect of exercise training on the length and circumference of atrophied muscles to see whether improvement in restoring the atrophied muscle mass, of either length or circumference growth could be induced through exercise training. Adult female Wistar rats were maintained for 14 days with hindlimb suspension. Rats were then assigned randomly to a sedentary group or training group. The length and circumference of both atrophied soleus and plantaris muscle for the training and sedentary groups following hindlimb suspension were compared with those of a control group. Length and circumference of both atrophied soleus and plantaris muscle in trained group was compared with those in the sedentary group. The results can be summarized as follows ; 1) Atrophy of soleus and plantaris muscle was induced with hindlimb suspension. 2) The circumference of both the soleus and plantaris muscle following hindlimb suspension was reduced to 51. 72%, 66.67% respectively compared to the control group. The length of both the soleus and plantaris muscle following hindlimb suspension did not show any difference compared to the control group. 3) There was no difference in length for either the atrophied soleus or plantaris muscle between the trained and the sedentary group during recovery from hindlimb suspension. 4) The circumference of both the atrophied soleus and plantaris muscle did not return to normal in the sedentary group, however, the circumference of both the atrophied soleus and plantaris muscle were significantly greater than of the control in the trained group, 14.22% and 9.38% respectively. 5) The circumference of both the atrophied soleus and plantaris muscle in the trained group was significantly larger than that of both muscles in the sedentary group at day 28 of recovery. From these results, it can be suggested that improvement in restoring the atrophied muscle mass through exercise training might be induced by growth of the muscle circumference.

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Evaluation of Upper Ocean Temperature and Mixed Layer Depth in an Eddy-permitting Global Ocean General Circulation Model (중해상도 전지구 해양대순환 모형의 상층 수온과 혼합층 깊이 모사 성능 평가)

  • Jang, Chan-Joo;Min, Hong-Sik;Kim, Cheol-Ho;Kang, Sok-Kuh;Lie, Heung-Jae
    • Ocean and Polar Research
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    • v.28 no.3
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    • pp.245-258
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    • 2006
  • We investigated seasonal variations of the upper ocean temperature and the mixed layer depth (MLD) in an eddy-permitting global ocean general circulation model (OGCM) to assess the OGCM perfermance. The OGCM is based on the GFDL MOM3 which has a horizontal resolution of 0.5 degree and 30 vertical levels. The OGCM was integrated for 68 years using a monthly-mean climatological wind stress forcing. The model sea surface temperature (SST) and sea surface salinity were restored to the Levitus climatology with a time scale of 30 days. Annual-mean model SST shows a cold bias $(<\;-2^{\circ}C)$ in the summer hemisphere and a warm bias $(>\;1^{\circ}C)$ in the winter hemisphere mainly due to the restoring boundary condition of temperature. The model MLD captures well the observed features in most areas, with a slightly deep bias. However, in the Ross Sea and Weddell Sea, the model shows significantly deeper MLD than the climatology-mainly due to weak salinity stratifications in the model. For amplitude of seasonal variation, the model SST is smaller $(1{\sim}3^{\circ}C)$ than the observation largely due to the restoring surface boundary condition while the model MLD has larger seasonal variation $({\sim}50m)$. It is suggested that for more realistic simulation of the upper ocean structure in the present eddy-permitting ocean model, more refinements in the surface boundary condition for the thermohaline forcing and parameterization for vertical mixing are required, together with the incorporation of a sea-ice model.

PALATELESS COMPLETE DENTURE FOR RESTORING GOOD TASTES : A CASE REPORT (미각 회복을 위한 무구개 의치(Palateless Complete Denture)의 임상증례)

  • Song, Eon-Hee;Kim, Rae-Gyoung;Ahn, Hyun-Jeong;Byun, Sook;Choi, Byeong-Gap
    • The Journal of Korean Academy of Prosthodontics
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    • v.37 no.6
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    • pp.819-824
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    • 1999
  • The purpose of this article is to present a clinical case report for palateless complete denture. Despite the contravacy of palatal uncoverage in upper complete denture, palateless complete denture has some merits for upper edentulous patient. Following the uncovering of the palatal portion, the patient became easy to talk and restored the lost good tastes. He is happy despite of the decrease of the retention of the upper complete denture. Palateless complete denture is a compatible alternative fir upper edentulous patients in cases of gagging, large palatal torus and restoring the lost good tastes. The clinical points are as follows : 1. The remaning alveolar ridge should be ovoid and have enough width and height for the sup-port and retention. 2. The patient must have strong wish to the palateless complete denture. 3. Palatal beading made on the palatal peripheral border give good border sealing of the palatal flange and minimaized the prominence of the denture flange 4. The peripheral border of the palatal flange should be reduced as thin as possible for more comfort. 5. Upper artificial posterior teeth should be arranged over the alveolar ridge crest and inner incline of the buccal cusp relieved for denture stability while chewing. 6. For stability of palateless complete denture, bilateral balanced occlusion should be sttained. Palateless complete denture will restore the lost good tastes and more comfortable and physiologic to upper edentulous patients and a good alternative to full palatal coverage complete denture in the properly selected cases.

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Reconstruction of Mandible Defect after Tumor Ablation Surgery : Versatility of Fibular Free Flap Design (광범위 종양절제술 후 발생한 하악 결손의 재건 : 결손부위에 따른 비골 유리 피판의 다양한 디자인)

  • Seul Chul-Hwan;Lee Young-Dae;Tark Kwan-Chul;Lew Dae-Hyun
    • Korean Journal of Head & Neck Oncology
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    • v.21 no.2
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    • pp.190-195
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    • 2005
  • Background and Objectives: Fibula is the flap of choice for reconstruction of wide mandible defects after tumor ablation surgery. In mandible reconstruction, restoring the mandible frame to provide mandibular contour and dental arch while restoring masticatory function are important. Even though vascularized fibula can be osteotomized freely, proper design and flap insetting is not easy because of its three dimensional structure and difference in design according to the defect sites. We reviewed patients who underwent mandible reconstruction with fibular flaps according to the defect sites and suggest proper modification methods of fibular flap according to the various defects sites after tumor ablation surgery. Materials and Methods: Twelve consecutive mandible reconstruction with fibular free flaps were performed for defects after tumor ablation surgery. Patients were classified into 4 groups according to the type of mandibular defect(Group 1 : defect on central segment including symphysis, Group 2 : defect on lateral segment(with or without central segment) confined to body, Group 3 : defect on body and ascending ramus that does not include the condyle, Group 4 : defect including the condyle). Results: We suggest different modification methods of fibular free flap for each patient group. Group 1, 3 ; contour by using multiple closing wedge osteotomy. Group 2 ; single or double barrel reconstruction without wedge osteotomy. Group 4 ; contour using single or multiple wedge osteotomy and condylar reconstruction with costochondral graft. Conclusion: Fibular free flaps can be contoured to any desired shape after multiple osteotomies to restore various mandibular defects. It is a reliable and versatile method for reconstruction of mandibular defects after tumor ablation surgery.

An Anthropometric and Three-Dimensional Computed Tomographic Evaluation of Two-Point Fixation of Zygomatic Complex Fractures

  • Jo, Taehee;Kim, Junhyung
    • Archives of Plastic Surgery
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    • v.41 no.5
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    • pp.493-499
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    • 2014
  • Background Maintaining stability and restoring the aesthetic appearance are the fundamental goals when managing zygomatic fractures. We aimed to evaluate the stability and anthropometric outcomes of zygomatic fracture patients who underwent two-point fixation involving the infraorbital rim and zygomaticomaxillary buttress via the transconjunctival and gingivobuccal approaches without any skin incisions. Methods We examined 15 zygomatic fracture patients who underwent two-point fixation during a 3-year period. Stability was evaluated using three-dimensional facial bone computed tomography. Superoinferior and anteroposterior displacement of the zygoma was quantified. The aesthetic appearance of the periorbital region was evaluated using indirect anthropometry with standardized clinical photographs. The ratios between the eye fissure height and width, and lower iris coverage ratio were used to evaluate aesthetical changes. The bony displacement and aesthetic ratios were analyzed using Wilcoxon or Friedman tests. The correlation between the preoperative zygoma position and anthropometric values was analyzed. Results The positions of the zygoma were similar to those on the contralateral side at the long-term follow-up. The preoperative anthropometric measurements on the fractured side differed from those on the contralateral side, although these values were close to the normal values at the long-term follow-up. Furthermore, we noted that the anteroposterior displacement strongly positively correlated with the lower iris coverage rate (Spearman's coefficient=0.678, P=0.005). Conclusions Two-point fixation of zygomatic fractures achieved stable outcomes on long-term follow-up, and also appeared to be reliable in restoring the aesthetic appearance of the periorbital region.

Digital Restoration of Cultural Properties Based on Virtual Reality (가상현실 기술을 이용한 문화재의 디지털 복원)

  • 박소연;양종열
    • Archives of design research
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    • v.16 no.1
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    • pp.219-228
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    • 2003
  • Nowadays, the progress of high technology in modern society provides humankind with the opportunity to obtain diverse information easily and quickly. Among those rapidly progressing fields of high technology, digital media field has the ability to substitute for the multimedia information society by being applied to many related fields and daily life. Specifically, the concern and enthusiasm for the restoration of cultural property has risen. So, effective methods are required to decide on the preservation, restoration and academic value of cultural property. Among these, image processing technology using computers has been introduced. The restoration of cultural property using this technique has been studied vigorously in many advanced countries because this would allow us to restore damaged parts without destroying the original asset. However, in Korea, though we have numerous examples of cultural property with recorded history, research related to the items has scarcely been conducted. Accordingly, this study focuses on the investigation of virtual reality and the techniques applicable to restoring cultural property in addition to suggesting the significance and possibility of digitally restoring cultural property following the introduction of applicable examples both domestically and abroad.

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Effect of Change in Water Content and NCO Index on the Static Comfort of Polyurethane Seat Foam Pad for Automobiles (물 함량과 NCO Index 변화가 자동차용 폴리우레탄 시트 폼 패드의 정적 안락감에 미치는 영향 고찰)

  • Lee, Byoung Jun;Lee, Sung Hoon;Choi, Kwon Yong;Kim, Sang-bum
    • Applied Chemistry for Engineering
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    • v.28 no.1
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    • pp.57-63
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    • 2017
  • In this study, we identified how the water content change in various NCO index affects the static comfort of polyurethane seat foam pad for automobiles. In order to identify factors that affect the static comfort, a static load test was performed using UTM to plot a hysteresis curve. The hardness of the foam when it was modified by 25, 65%, hysteresis loop area, hysteresis loss (%), and Sag factor were also obtained. By measuring the swelling ratio, it was confirmed that, as the water content increased in a fixed NCO index, the hardness and crosslinking density increased while the restoring force decreased due to the increase of urea bond. Also the Sag factor decreased due to the increase of surface hardness. As the NCO index increased in a fixed water content, the urethane and urea bond reacted more with isocyanate, leading to an increase in hardness and decrease in restoring force.