• Imaging Science in Dentistry
• /
• v.50 no.1
• /
• pp.65-71
• /
• 2020

Ossifying fibroma is a slow-growing benign neoplasm that occurs most often in the jaws, especially the mandible. The tumor is composed of bone that develops within fibrous connective tissue. Some ossifying fibromas consist of cementum-like calcifications, while others contain only bony material; however, a mixture of these calcification types is commonly seen in a single lesion. Of the craniofacial bones, the mandible is the most commonly involved site, with the lesion typically inferior to the premolars and molars. Ossifying fibroma of the jaw shows a female predominance. Some reports of ossifying fibroma have been published in the literature; however, this report continues the research on this topic by detailing 3 types of ossifying fibroma findings on panoramic radiographs and cone-beam computed tomographic images of 4 patients. The radiographs of the presented cases could help clinicians understand the variations in the radiographic appearance of this lesion.

• Proceedings of the Korean Society For Composite Materials Conference
• /
• 2001.10a
• /
• pp.57-60
• /
• 2001

In order to extend the life time of building and civil infra-structure, nowadays, patch type fibrous composite materials are widely used. Retrofitted concrete columns and beams gain the stiffness and strength, but they lose toughness and show brittle failure. Usually, the cracks of concrete structures are visible with naked eyes and the status of the structure in the life cycle is estimated with visible inspection. After retrofitting of the structure, crack visibility is blocked by retrofitted composite materials. Therefore, structural monitoring after retrofitting is indispensible and self diagnosis method with optical fiber sensor is very useful. In this paper, We try to detect peel out effect and find the strain difference between main structure and retrofitting patch material when they separate each other.

• Korean Journal of Veterinary Research
• /
• v.42 no.3
• /
• pp.419-423
• /
• 2002

Postoperative suture granuloma have rarely been reported in animals. Eight biopsy masses from testes areas of neutralized dogs were diagnosed as suture granuloma. The suture granuloma occurred at any time from several weeks to a few years after surgery and appeared to be testicular tumors by macroscopic examination. The granulomas were classified into three types based on the histopathological findings. The first type of pyogranuloma was mainly composed of neutrophils, macrophages, and suture fragments. The second type was chronic necrotizing granuloma which was well demarcated by fibrous connective tissues and was composed of a few suture fragments, macrophages and central fibrinoid necrosis. The third type of granuloma had a poorly defined margin with scarcely observed suture fragments and central necrosis in the tissue. These histopathological findings suggested that various types of suture granuloma may be caused by suture material and could even appear long after surgery.

• Fibers and Polymers
• /
• v.2 no.2
• /
• pp.71-74
• /
• 2001

Surface characterization of materials has been considered critical in the development of biomaterials, as many unfavorable responses from the body occur at the interface between a material and the body component. The contact angle measurement is one means to characterize the surface properties and to correlate them to the biocompatibility of materials. In this paper, surface characteristics of silk fibroin/S-carboxymethyl kerateine, representative fibrous proteins, were investigated by contact angle measurements of ESCA. The biocompatibility of the blends was evaluated based on minimal interfacial free energy concept, and compared with other potential biomaterials. It was also hypothesized that the enhanced surface polarity of the blends was generated from the conformational transition of proteins. This approach to evaluate the biocompatibility of materials based on surface characteristics may find wide utility in many biomedical applications.

• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.21 no.8
• /
• pp.726-732
• /
• 2011

Straight absorptive silencers have been designed to reduce the noise level of a centrifugal blower. Three-dimensional boundary element method is used for the design of absorptive silencers which consist of a perforated main pipe and a outer chamber filled with fibrous material. The experimental results show that the absorptive silencer reduces up to 8 dB(A) in the overall sound pressure level of the blower and up to 15 dB at the blade passing frequency. It is also found that the gap between the silencer and the impeller may substantially alter the acoustic performance of the silencers. The transmission loss predicted by the boundary element method follows overall trends of the measured insertion loss. The experiments also show that the impact of the silencers on the aerodynamic performance of the blower is minimum.

• Journal of Korea Technical Association of The Pulp and Paper Industry
• /
• v.31 no.2
• /
• pp.70-76
• /
• 1999

This study was to measure the potential of nonwoody fibrous material, kenaf. Whole stalk of kenaf, Hibiscus cannabinus was separated by two parts of bast and core portion, and cooked separately by alkaline method. Morphological characteristic was evaluated using confocal laser scanning microscope (CLSM) and fiber quality analyzer(FQA). The strength properties of handsheets, made by different mixing ration between kenaf base and core fibers, were measured. Cross-sectional area of bast fibers was smaller than that of core fibers, but the bast fibers had a thick cell wall and narrow lumen area. Bast fibers were longer in length than core fibers. Core fibers had thin cell walls, broad lumen areas, and short lengths, and they had collapsed shape even in water. These characteristics of core fibers affected strength properties of handsheet positively. When the amount of core fibers increased, the strength properties of handsheet were increased. When the amount of bast fibers increased, the handsheet had rougher surface and higher air permeability.

• Journal of the Korean Society for Heat Treatment
• /
• v.14 no.5
• /
• pp.286-291
• /
• 2001

This study was carried out to investigate the influence of ${\sigma}$ phase on the microstructure and mechanical properties in super duplex stainless steel. The precipitation of ${\sigma}$ phase during isothermal heat treatment showed the type S curves with a certain incubation period. The precipitation of ${\sigma}$ phase was precipitated at ferrite phase and interface of ferrite and austenite. Under the state of isothermal transformation, the precipitation of ${\sigma}$ phase was stimulated by applied stress. With increasing of volume fraction of precipitated ${\sigma}$ phase, tensile strength was increased and elongation was decreased with linear relationship, while in case of precipitated ${\sigma}$ phase was 5% over, impact value was rapidly decreased.

• The Korean Journal of Cytopathology
• /
• v.5 no.1
• /
• pp.28-34
• /
• 1994

Aspiration biopsy cytology is a convenient, easy and non-invasive method for diagnosis of tumors. The results and cytologic features of carcinoma in various organs have been reported frequently, however, those of soft tissue sarcoma are relatively rare to find. Here we describe fine needle aspiration cytologic features of various soft tissue sarcomas and discuss cytologic differential points. The material is 6 cases of soft tissue sarcoma that were confirmed by histologic examination. They are composed of 2 cases of dermatofibrosarcoma protuberans and one case of malignant fibrous histiocytoma, synovial sarcoma, alveolar soft pan sarcoma, and malignant schwannoma respectively.

• Journal of Korea Foundry Society
• /
• v.23 no.1
• /
• pp.47-51
• /
• 2003

This experimental study was carried out to investigate the solidification characteristics of polystyrene added styronaphthalene pattern materials using various castability test methods. The styronaphthalene showed an excellent filling capacity and shaping behavior having about 0.2 mm meniscus radius. The shell thickness of styronaphthalene showing smooth wall at the solid/liquid interface increased with the increasing of polystyrene addition. The solidification microstructure of styronaphthalene showed a typical thin ribbon reinforced composite structure, which has fibrous amorphous skeleton of polystyrene and crystalline naphthalene. From the results of this study, it was found that the polystyrene added styronaphthalene showed a precision shaping behavior as disposable pattern material under the atmospheric condition.

• Journal of the Korean Ceramic Society
• /
• v.11 no.4
• /
• pp.25-30
• /
• 1974

The mixture of quartz powder and slaked lime with plenty water was oscillated in an autoclave and treated hydrothermally under the pressure of 10 kg/$\textrm{cm}^2$ for 8 hours. The main mineral synthesized was confirmed 11$\AA$ tobermorite by the method of X-ray diffraction and selected area electron diffraction. Tobermorite was heat-treated at 40$0^{\circ}C$, 80$0^{\circ}C$ and 100$0^{\circ}C$ for investigation of transformation of morphology and structure. Electron micrographs showed the thin platy structure of synthetic tobermorite with a little of crumpled foil or fibrous semi-crystalline calcium silicate hydrates. No difference in structure was appeared under the temperature of 80$0^{\circ}C$ but tobermorite converted gradually into wollastonite at 800$^{\circ}$~85$0^{\circ}C$. On heating, moulded material from tobermorite hardly shrinks under 80$0^{\circ}C$.