• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1995.11a
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• pp.171-174
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• 1995

Space charge formation in epoxy loaded with silica and calcium carbonate has been studied. The epoxy itself showed almost no charge at up to 40 kV/mm. The addition of fillers such as SiO$_2$and CaCO$_3$resulted in homocharge formation, which was attributed to the interfacial trapping of injected charge at epoxy/filler interfaces. The amount of charge showed a maximum at 20-40 parts per hundred resin above which the charge decreased gradually. This was tentatively attributed to the enhanced interconection of charge transport path by an increased filler content

• Maxillofacial Plastic and Reconstructive Surgery
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• v.33 no.5
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• pp.425-429
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• 2011

Bone grafts are becoming increasingly common in oral and maxillofacial surgery to improve bone healing procedures. Bovine bone as a xenograft is a representative osteoconductor and space filler; however, sometimes complications, such as infection and wound dehiscence are encountered with its use. We report the result of an eight-year follow-up of a xenograft case and processing methods of inorganic bovine bone along with a review of the literature. Xenograft ($LUBBOC^{(R)}$) was used in a cyst enucleation site of the maxilla, as a bone substitute and space filler. Inflammation and infection were defined several times as lack of osseous contact between the graft and host bone, caused by remodeling failure over an eight-year period. Pathologic findings of the xenograft revealed dead bony trabeculae with inflamed fibrous tissue and actinomycosis.

• Journal of Chest Surgery
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• v.46 no.1
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• pp.1-13
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• 2013

Background: Glutaraldehyde (GA) is a widely used cross-linking agent for improving mechanical properties and resistance to enzymatic degradation of collagenous tissue, but it has several drawbacks such as calcification and cytotoxicity. The aim of this study was to find the alternative effective cross-linking methods to GA. Materials and Methods: Bovine pericardium was processed with GA with ethanol+octanol and glycine detoxification, and polyethylene glycol (PG) space filler, dimethyl 3,3'-dithiobispropionimidate (DTBP), 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) treatment, and the physical fixation of ultraviolet irradiation were done. The biologic material properties of variously treated pericardial tissues were assessed by biochemical, mechanical and histological tests. Treated pericardial tissues were also implanted subcutaneously or intramuscularly into the rabbit for 10 weeks to assess the xenoreactive antibody response of immunoglobulin G and M, their anti-calcification effect. Results: The biochemical and mechanical properties of EDC fixed pericardial tissues were comparable to the GA fixed tissue. The cytotoxicity was lowest in space filler treated GA fixed group. In rabbit subcutaneous or intramuscular implantation models, decellularization, space filler, EDC treatment group showed significantly lower calcium content than GA only and DTBP treatment group (p<0.05, analysis of variance). The titer of anti $Gal{\alpha}1-3Gal{\beta}1$-4GlcNAc-R antibodies did not change in the postimplantation serial enzyme-linked immunosorbent assay. Hematoxylin and eosin and von Kossa staining showed that decellularization, space filler, EDC, and ultraviolet treatment had less inflammatory cell infiltration and calcium deposits. Conclusion: The decellularization process, PG filler, and EDC treatments are good alternative cross-linking methods compared to GA only fixation and primary amine of DTBP treatment for cardiovascular xenograft preservation in terms of the collagen cross-linking stability and in vivo anti-calcification effects.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.7
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• pp.112-117
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• 2003

The brazing of copper alloys and duplex stainless steels is an indispensable manufacturing technology for thrust chambers with regenerative cooling. For setting up the optimized brazing conditions, C18200 copper alloy plate with machined cooling channels and S31803 stainless steel plate are brazed with AMS4764 filler metals of which thickness is 50${\mu}m$ and 80${\mu}m$ They are tested by X-ray radiography, strength/leakage and fracture tests, and fracture surface inspection. The results obtained by the suggested conditions are that the specimen brazed with filler metal thickness of 50${\mu}m$ has good strength properties and brazed zone. However, the specimen with filler metal thickness of 80${\mu}m$ has the brazed zone with cooling channel obstruction and enlargement.

• Journal of the Korea Institute of Building Construction
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• v.22 no.3
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• pp.239-249
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• 2022

Fire resistance performance and performance design of fire doors are becoming more important to prevent the spread of fire and support the rapid evacuation of apartment buildings. In this study, a database using 182 evacuation spaces and 308 common areas that passed the fire performance test was established, and fire door performance influencing factors were derived through an analysis of the structure(12 elements) of the fire door. As a result, the effects of fire-resisting filler density, adhesive, and foam gasket were confirmed for evacuation space, and the effects of fire-resisting filler, adhesive, and fire fins were confirmed for common areas. In the fire door fire resistance test, flames and cracks were analyzed as the most frequent failure factors.

• Proceedings of the KIEE Conference
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• 1986.07a
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• pp.140-144
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• 1986

In this paper an FIR(finite impulse response) filter and smoother are introduced for discrete time-invariant state-space models with driving noises. The FIR structure not only quarantees the BIBO stability and the robustness to parameter changes but also improves the filter divergence problem. It is shown that the impulse responses of the FIR filter and the smoother are obtained by Riccati-type difference equations and that they are to be time-invariant and reduced to very simple forms. For implementational purpose, recursive forms of the FIR filler and smoother are derived with each other used as the adjoint variable.

• Journal of the Microelectronics and Packaging Society
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• v.24 no.4
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• pp.1-7
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• 2017

Aluminum alloys have been widely used in many fields such as electronic, structure, aero-space and vehicle industries due to their outstanding thermal and electrical conductivity as well as low cost. However, they have some difficulties for using in brazing process because of the strong oxide layer of $Al_2O_3$ on the surface of Al alloy. In addition, their melting point is similar to that of brazing filler metal resulting in thermal damage of Al alloys. Therefore, it is very important to understand the brazing principles, filler metal and its properties such as wetting, capillary flow and dissolution of base metal in the Al brazing process. This paper reviews the brazing principles, aluminum alloys, and brazing fillers. In the case of brazing principle, some formula was used for calculation of capillary force and the dissolution to obtain the best condition of Al brazing. In addition, the advanced research trends in Al brazing were introduced including thermal treatment, additive for improving property and decreasing melting point in Al brazing process.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.43 no.5
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• pp.43-48
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• 2011

Filler loading at thick stock was carried out in order to verify if the dual addition of filler can be used as a means to reduce the detrimental effects of filler on the strength properties of paper. PCC was added to 3.5% pulp slurry blended with HwBKP, BCTMP and SwBKP. Cationic starch was used as a fixing agent. The mixture of PCC and pulp was stirred for 5, 10 and 20min. at 1,000 rpm. The remaining PCC was washed out before handsheet making. PCC particles were flocculated and fixed on the pulp fiber and/or space between fibers. It is expected that the flocculation and inclusion of PCC can be helpful to improve the strength properties of paper due to the reduction of detrimental effect in fiber bonding. The distinct tendency in PCC flocculation and fixing on pulp fiber was not observed by the change of cationic starch dosage and treatment time.

• Proceedings of the IEEK Conference
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• 2000.06d
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• pp.218-221
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• 2000

In this paper, we propose a new algorithm to detect human faces for controling a camera used in video conference. We model the distribution of skin color and set up the standard skin color in YIQ color space. An input video frame image is segmented into skin and non-skin segments by comparing the standard skin color and each pixels in the input video frame. Then, shape filler is applied to select face segments from skin segments. Our algorithm detects human faces in real time to control a camera to capture a human face with a proper size and position.

• Journal of the Korea Institute of Building Construction
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• v.4 no.3
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• pp.93-100
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• 2004

In recent years, it has widely been studied on the light-weight composites for the purpose of the large space and thermal insulation of building structures. The purpose of this study is to evaluate the properties of light-weight composites made by binders as cement, resin and polymer cement slurry. The concrete composites are prepared with various conditions such as polymer-cement ratio, void-filling ratio, type of resin, filler content and light-weight aggregate content, tested for thermal conductivity. From the test results, the thermal conductivity of concrete composites with the binder of cement tends to decrease with increasing polymer-cement ratio, and to increase with increasing void-filling ratio. The thermal conductivity of concrete composites with the binder of resin are markedly affected by the light-weight aggregate content, type of resin and filler content. The composites made by polymer-modified concrete and polymer cement slurry have a good thermal insulation property. From the this study, we can recommend the proper mix proportions for thermal insulation Panel or concrete. Expecially. the thermal conductivity of concrete composites made by polyurethane resin is almost the same as that of the conventional expanded polystyrene resin.