• Proceedings of the Korean Society For Composite Materials Conference
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• 2003.04a
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• pp.99-102
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• 2003

Carbon/Epoxy composite specimens formed with buttress groves are fabricated. The buttress form of groove is useful in any application where high shear loads are transferred in one direction between structural components. It is a primary object of the present study to test and evaluate the shear load carrying capability of a carbon/epoxy composite structure with buttress grooves for military applications

• Journal of Chest Surgery
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• v.27 no.2
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• pp.153-156
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• 1994

Bentall`s operation for repair of annuloaortic ectasia has been associated with postoperative bleeding and with false aneurysm of the anastomotic site between the coronary orifice and composite graft.Among 5 cases, 2 cases have been operated direct anastomosis between coronary artery and vascular graft.Remained 3 cases have been operated with doughnutlike Teflon felt buttress.The technique of sandwiching the freed button of aortic wall bearing the coronary artery ostium between an outer Teflon felt doughnutlike buttress and the inner composite graft provides a leak-proof anastomosis.We experienced one case reoperation for bleeding at coronary anastomotic site above method.

• Water for future
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• v.10 no.2
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• pp.30-43
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• 1977

• Journal of the Korean Society of Hazard Mitigation
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• v.2 no.4 s.7
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• pp.131-141
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• 2002

Precast concrete (PC) panels are often used as retaining walls to support soil pressure. In such a case, the panels should be connected at the location where PC panels meet with a buttress. However, it is not easy to provide enough development length for the reinforcing steels due to the limited width of the buttress. If it happens, the width of buttress should be increased as large enough although it is not desirable. The critical section required for providing the development length is always located where the flexural moment is maximum. Thus it is the place the buttress width ends. Also it is the place that the reinforcing steels stressed to maximum. However, it is possible to make differentiate between the maximum moment location and the most stressed location of reinforcing steels. It means that the most stressed location of reinforcing steels, the critical section, can be moved to the other place where the moment is not maximum. New critical location will have less moment than that of buttress width ends. In consequence, the development length would be longer than that of the typical way of construction. Debonding or cutting technique make it possible to reduce the moment strength of a section. Therefore reinforcing steels are debonded or cut to have a desired flexural strength at a desired place. In this study, five test specimens in full scale were erected to examine the effects of critical section movement in PC panel joints. Test parameters were the length variations of debonded and cut reinforcing steels. The test results showed that the debonding or cutting technique could be used to lengthen the development length in the joint of PC panels.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2009.11a
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• pp.9-13
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• 2009

Recently, construction in downtown is often done closely at the adjacent building. In this case, underground construction need to Basement Composite Wall(BCW) construction. However, generally, during the construction process of BCW form works have many problems that are narrow working space and inefficient time consuming. Despite of these problems, there was no quantitative research for the work time of BCM assembly. Therefore, in this study, work time of CBW form assembly in underground construction is identified by the work analysis. The results of this study reveal that buttress work of basement form take lots of time in the entire work process of Basement Composite Wall form assembly.

• Journal of Korean Foot and Ankle Society
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• v.25 no.4
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• pp.181-184
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• 2021

End-stage ankle arthritis is a debilitating condition that causes functional limitations and consequently a poor quality of life. Total ankle replacement arthroplasty is a good alternative to arthrodesis for preserving the ankle's range of motion. However, many complications can occur in patients with rheumatoid arthritis and with poor soft tissue and bone conditions. A 61-year-old female experienced spacer subluxation after surgery, which was not reduced by medial soft tissue release and spacer change. Buttress plating was found to be a good treatment option to prevent spacer subluxation and can be considered in patients with rheumatoid arthritis with bone erosion and soft tissue damage.

• Journal of the Korean Geotechnical Society
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• v.35 no.11
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• pp.15-23
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• 2019

In this study, the displacement of soft clay layer with installed Buttress type Self supporting Composite Wall (BSCW) was investigated using numerical method. The model was validated using the field displacement data at the front center of BSCW and parametric analysis of the model was implemented at varied cohesion, elastic modulus of 3 different clay layers (soft, medium, and stiff). In addition, parametric study was also performed for varied center-to-center distance of bottom cement grouting columns installed by jumbo special pattern (JSP) method. The results of parametric study demonstrated that the displacement of BSCW is the most significant in soft clay layer and low center-to-center distance of grouting columns is required at relatively low elastic modulus of clay layer.

• Journal of the Society of Disaster Information
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• v.12 no.4
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• pp.366-372
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• 2016

Recently in case of the concrete retaining wall precast technological change in the field assembled by the way. A precast wall is devied into upper and lower respectively, and the way, assembled in field is being performed. But the assembled part could have been damaged by the earth pressure in a relatively high buttress wall. And, it have been pointed out that large-scale disaster can be occurred. Thus, in this thesis, a structural stability for the buttressed retaining wall with pre-cast joint method was analyzed by a numerical analysis method. The structural stability of the three height retaining wall(7.6m, 8.5m, 10m) was conducted respectively for earth pressure. The maximum principal stress applied to the concrete retaining wall was analyzed to occur locally in the vicinity of the fixing anchor as 23.3 ~ 43.2 MPa.

• Journal of the Korean Wood Science and Technology
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• v.50 no.2
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• pp.113-125
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• 2022

This study aimed to explore the biodiversity of chemical compounds found in the bark of Guibourtia tessmannii from Gabon, commonly called Kévazingo, and evaluate their anti-termite activity to determine their potential values as a source of development of anti-termite products that can be valued in the fields of fine chemicals and wood preservation. Extraction of G. tessmannii bark powders was carried out using the cold maceration method with trichloroethylene, acetone, ethanol, and water. Phytochemical screening made it possible to highlight groups of chemical families present in the extracts. Anti-termite activity was tested on the wild termites "Cubitermes sp" of the genus Isoptera. The yield of the extracts were 17.11% for the buttress and 13.42% for the height at 6 m. Phytochemical tests revealed that alkaloids, polyphenols, sterols, tannins, reducing compounds, flavonoids, saponins, and anthraquinones were present in the extracts. Results of anti-termite activity indicated that anti-termite activity varied with the different parts of the bark studied, extraction solvent, and concentration (50/50) and (25/75) of the extracts used. The extracts at 50/50 concentration showed a slightly better anti-termite activity compared to the 25/75 concentration. In addition, the buttress Kévazingo or buttress showed the strongest anti-termite activity for the aqueous extract with a survival rate of 0% after 2 days.

• The Journal of Korean Academy of Prosthodontics
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• v.52 no.4
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• pp.279-286
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• 2014

Purpose: The aim of this study was to investigate the effect of implant thread profile on the marginal bone stresses which develop during implant insertion. Materials and methods: Four experimental implants were created by placing four different thread systems on the body ($4.1mm{\times}10mm$) of the ITI standard implant. The thread types studied in this study included the buttress, v-shape, reverse buttress, and square shape threads. In order to examine the insertion stress generation, 3D dynamic finite element analysis was performed which simulated the insertion process of implants into a 1.2 mm thick cortical bone plate (containing 3.5 mm pilot hole) using a PC-based DEFORM 3D (ver 6.1, SFTC, Columbus, OH, USA) program. Results: Insertion stresses higher than human cortical bone developed around the implants. The level of insertion stresses was much different depending on the thread. Stress level was lowest near the v-shape thread, and highest near the square shaped thread. Difference in the interfacial bone stress level was more noticeable near the valley than the tip of the threads. Conclusion: Among the four threads, the v-shape thread was turned out to minimize the insertion stress level and thereby create better conditions for implant osseointegration.