• Geomechanics and Engineering
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• v.10 no.5
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• pp.657-676
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• 2016

In this paper, the active lateral earth pressure is evaluated using the stress characteristics or slip line method. The lateral earth pressure is expressed as the lateral earth pressure coefficients due to the surcharge, the unit weight and cohesion of the backfill soil. Seismic horizontal and vertical pseudo-static coefficients are used to consider the seismic effects. The equilibrium equations along the characteristics lines are solved by the finite difference method. The slope of the ground surface, the wall angle and the adhesion and friction angle of the soil-wall interface are also considered in the analysis. A computer code is provided for the analysis. The code is capable of solving the characteristics network, determining active lateral earth pressure distribution and calculating active lateral earth pressure coefficients. Closed-form solutions are provided for the lateral earth pressure coefficients due to the surcharge and cohesion. The results of this study have a good agreement with other reported results. The effects of the geometry of the retaining wall, the soil and soil-wall interface parameters are evaluated. Non-dimensional graphs are presented for the active lateral earth pressure coefficients.

• Radioisotope journal
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• v.21 no.4
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• pp.46-54
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• 2006

Biocompatible and biodegradable hydrogels based on carboxymethyl cellulose(CMC) and polyethyleneglycol(PEG) were prepared far physical barriers for preventing surgical adhesions. These interpolymeric hydrogels were synthesized by a gamma irradiation crosslinking technique. The 1Scmxl.Scm of cecal serosa and adjacent abdominal wail were abraded with bane burr until tbe serosal surface was disrupted and hemorrhagic but not perforated. and the serosa of tbe cecum was sutured to the abdominal wall in 5mm apart from the injured sire. The denuded cecum was covered with either CMC/PEG hydrogels or solution from CMC/PEG hydrogel. Control rat serosa was not covered. Two weeks later. the rats were sacrificed and adhesion was scored on a 0-5 scale. No treatment showed the significantly higher incidence of adhesions than either CMC/BEC hydrogels or solution from CMC/PEG hydrogel. In conclusion, these studies demonstrate that CMC/BEG hydrogels have a function of prevention of intra abdominal adhesion in a rat model.

• Journal of Periodontal and Implant Science
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• v.28 no.2
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• pp.219-237
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• 1998

Numerous bone graft materials have been used in Periodontics, in an attempt to reach the main goal of periodontal therapy, i.e. the regeneration of periodontal tissue lost due to destructive periodontal diseases. The present study investigates the effect of composite graft of DFDB and Calcium sulfate with and without Calcium sulfate barrier in Periodontal 1-wall intrabony defects in dogs. Following the initiation of general anesthesia by I.V. administration of 40mg/Kg of Pentobabital, second premolar was extracted and full thickness flap elevated. The crown portion of premolars was removed. Exposed root canals were sealed with Caviton and covered completely with flap. After the healing period of 8 weeks, the surgical sites were re-opened and 1-wall intrabony defects were created, and treated with flap operation alone(control group), with composit graft of 80% DFDB and 20% Calcium sulfate(Experimental group 1), with composite graft of DFDB and calcium sulfate with calcium sulfate membrane( Experimental group 2). Healing response was histologically observed after 8 weeks and the results were as follows : 1. New bone formation was 70 % in the control group, 93 % in the Experimental group I, 89 % in the Experimental group II. There was a no differences between Experimental groups. 2. New cementum formation was not significantly different between control and two Experimental groups. 3. The length of connective tissue adhesion was 30 % in the control, 7% in the Experimental group I and 11 % in the Experimental group II. 4. After 8weeks, calcium sulfate was completely resorbed, while DFDB particle remained. These results suggest that the use of composite graft of allogenic DFDB and Calcium sulfate with and without Calcium sulfate barrier in periodontal 1 wall intrabony defects have little effect on connective tissue adhesion, but has beneficial effect on new alveolar bone and new cementum formation, and prevent downgrowth of epithelium and connective tissue effectively.

• Proceedings of the Membrane Society of Korea Conference
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• 1998.04a
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• pp.105-109
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• 1998

1. Introduction : In microfiltration the transport, deposition and removal of particles control cake formation on a filter. In this connection a new model on cake formation, based on the wall shear stress, was tested here in comparison with experiments of fine particle slurry under Taylor-vortex flow. The model expresses the deposition process for particles as two first-order steps in series of mass transfer and adhesion, and their removal process as a linear relation to the wall shear stress. This embraces characteristics of both dead-end and crossflow filtration. The correlation resulting from fitting to experimental data represented the experimental data reasonably well. This study will be helpful in analyzing fouling in heat exchangers.

• The Journal of the Convergence on Culture Technology
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• v.6 no.1
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• pp.477-483
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• 2020

The rehabilitation methods used in existing concrete box structures rely on the method of attaching the repair material to the section of the structure with a spray equipment. In the case of ceiling or wall parts, the adhesion force to the repair material may be reduced by the gravity and dead load after construction. In subway structures, vibration causes a problem that reduces the initial adhesion. Supplementary measures are needed as the quality of repair varies depending on the worker's proficiency and construction environment. In this study, mechanical pressurization equipment was developed that can apply a certain pressure after construction of a repairwork to solve problems such as reduction of adhesion of repair materials by gravity and variation of repair quality by labor work. To find out the effect of the pressurized equipment, a chamber similar to the field conditions was constructed to measure the attachment strength different from the pressurized condition, the section, and the environmental conditions. The pressurization differed from the other parts, but the adhesion strength of up to 70% was increased.

• Restorative Dentistry and Endodontics
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• v.25 no.1
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• pp.116-122
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• 2000

On the instrumented root canal wall, amorphous, irregular smear layer can be observed with Scanning Electron Microscope(SEM). The purpose of this study was to evaluate the effect of the presence or absence of smear layer on the adhesion of Staphylococcus aureus to the dentin of the root canal. Human incisors, extracted within 7 days, with no caries, no fracture, no calcification of canal, were selected. After cutting crown portion at cemento-enamel junction, root canal preparation was done by modified crown-down technique using Profile and Gates - Glidden Drill. During canal preparation, 10ml physiologic saline solution(group1&3) or 10ml 3.5% NaOCl(group2&4) was used as irrigation solution. And 10ml physiologic saline solution(group1&3) or 10ml 0.5M EDTA(group2&4) was applicated for final flush. After vertical sectioning and ethylene oxide gas sterilization, samples(group1&2) were immersed into BHIYHM broth inoculated with Staphylococcus aureus (ATCC 31153) and incubated for 3hrs at $37^{\circ}C$. All samples were prepared for and observed with SEM(JEOL JSM840S). The data were analyzed by Mann-Whitney rank sum test. The conclusions are as follows ; 1. Smear layer covers entire root canal surface after root canal preparation. 2. Smear layer has been removed away and the entrances of dentinal tubules have opened widely, when applying 0.5M EDTA and 3.5% NaOCl. 3. A significantly higher number of bacteria were adhered to the root canal dentin without smear layer(p<0.0001). 4. Smear layer produced during root canal preparation impedes bacterial adhesion and colonization to dentin matrix, therefore inhibits canal reinfection.

• The Korean Journal of Mycology
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• v.35 no.1
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• pp.1-10
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• 2007

The cell wall is essential for the survival and osmotic integrity of fungal cells. It is the framework to which biologically active proteins such as cell adhesion molecules and hydrolytic enzymes are attached or within which they act. Recently it was shown that mutations in ${\alpha}-COP$, a subunit of COPI vesicle, is responsible for the thermo-sensitive osmo-fragile phenotype of fungi, such as Saccharomyces cerevisiae and Aspergillus nidulans, and suggested that ${\alpha}-COP$ may play a crucial role in translocation of protein(s) of the ${\beta}-1,3-gulcan$ synthase complex and cell wall proteins, thus may contribute to the maintenance of cell wall integrity. In this review, we summarized the relationship between the intra-cellular protein translocation machinery, especially the ${\alpha}-COP$ of COPI vesicle, and cell wall biogenesis in fungi. We also discussed potential use of secretory mutants in basic and applied research of the fungal cell walls.

• Journal of Trauma and Injury
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• v.25 no.2
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• pp.63-66
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• 2012

Resection of the bowel is necessary for the repair of a ventral hernia after recovery from trauma in some cases. In such instances, polyester or polypropylene meshcannot be used due to the possibility of infection; we had to use biological mesh instead. We report a case in which a traumatic hernia was repaired with Permacol (Covidien, Norwalk, CT, USA). A 42-year-old male patient had been injured by a factory machine seven months prior to admission. At that time, he had abdominal wall injury and small bowel perforation. His abdominal wall had been a defect after operation. A CT scan of the abdomen showed that the left abdominal wall, which is lateral to left rectus abdominis muscle had only one muscle layer, an external oblique muscle, and that a previous abdominal incision had a defect along the entire incision. During the exploration, 10 cm of small bowel was removed due to firm adhesion to the previous surgical scar. Permacol mesh was applied and fixed with transfascial fixations and tacks by using the intraperitoneal onlay mesh technique. There were no complications after the surgery and the patient was discharged without any problems.

• Archives of design research
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• v.19 no.2 s.64
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• pp.207-216
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• 2006

Even though the notion exists that wall paper has got a short durability for interior decoration in terms of paper's nature, it can be the most important element among the modern dosing wall papering because of the variation of the walls visual effect. Wall paper hasn't been preserved well according to the paper's character and official records haven't been done well. So, by studying a case in which a room is maintained well, seeing various commercial samples which were used for an advertisement and reading several booklets it is possible to study historical evidence. In regard to wall paper and Papering. data, the commercial historic nature of the traditional wall papering has been recognized again in order to study the root of the technical and commercial background. In theory, the historic background research of traditional wall paper in the past is said to have established its theoretical system and the development of modern wall papering in the middle of Britain in 18th century. Through the theoretical study of wall papering, the following things have been researched: handling don the method of the traditional wall papering and lining paper, stylization of pattern by using the method of continual linking, subdivision of commercial cost and specialization of wallpaper, handing down the past traditional adhesion method, the origin of string wallpaper, utility of traditional wallpaper and its various abilities, the change from the face to face linking to duplicated linking, the development of DIY products by women's wallpaper selections. Put against other materials, wallpaper remains the most popular and preferable product for managing a wall and provides a decorative, wall dosing technique. This study can estimate the source of wallpapering history in order to create a systemic approach towards the future's wallpaper industry. This is very important data in order to establish a theoretical system of traditional wallpapering according to its historical research about wallpapering skills and its commercial aspect.

• Journal of Adhesion and Interface
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• v.11 no.4
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• pp.174-180
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• 2010

The effect of carbon nanotube surface treatment on the interface and thermal conductivity of carbon nanotube-based poly(methylmethacrylate) (PMMA) composites was investigated. Coagulation and atomic-transfer radical polymerization (ATRP) was applied to modify the surface of multi-wall carbon nano-tube. The composite of ATRP method used carbon nanotube showed the higher transparency and thermal conductivities than that of the coagulation method used. In comparison to the thermal conductivity of pure PMMA, 0.21 W/mK, the ATRP carbon nanotube used PMMA/MWNT composite showed a thermal conductivity of 0.38 W/mK. The interface between carbon nanotube and PMMA was observed by scanning electron microscope and uniform dispersion of carbon nanotube was observed without any void in the PMMA matrix. It may be beneficial to transport the phonon without any scattering and it may result in a higher thermal conductivity.