• Convergence Security Journal
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• v.6 no.2
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• pp.31-42
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• 2006

In this paper, we proposed an integrated infrastructure for optimal information security to resolve these kinds of problems and to implement more powerful protection. The proposed infrastructure presents a security framework, provides a functional mechanism, and implements a scheme for information security based on the design concept of integrated structures. In order to ensure effective malicious traffic blocking, this paper emphasizes that a comprehensive approach through infrastructure improvement and combination of scanning tool is the only measure for preparing against today's environment of virus infiltration. The proposed model is a measure developed at a time when a permanent technological solution to virus is yet to be developed. A performance analysis model is developed and the performance is evaluated through the case studies for the proposed methodology. The effectiveness of the infrastructure for optimal information security needs the continuous diagnostic evaluation and tuning through the users or the organizations.

• The Korean Journal of Cytopathology
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• v.16 no.2
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• pp.110-114
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• 2005

Primary leptomeningeal glioblastomatosis is a rare and fatal tumor of the central nervous system, the condition is characterized by diffuse infiltration of the tumor in the meninges without evidence of primary tumor within the brain or spinal cord. We reported an unusual case of leptomengial glioblastomatosis, which was detected by the consecutive cerebrospinal fluid (CSF) cytology with application of immunohistochemistry, in addition to its cytologic findings. A healthy 21 year old man, who was enlisted in the army, presented with a stuporous mental state and diffuse enhancement of meninges without evidence of primary mass lesion in the brain and spinal cord on magnetic resonance imaging(MRI). CSF cytology showed small loose clusters of tumor cells with single cells and lymphocytes. The tumor showed variable pleomorphism with coarse chromatin, irregular nuclear membranes and multi lobated nuclei. On immunohistochemical staining, the tumor cells were founded to be positive for GFAP. In conjunction with radiologic findings, brain biopsy confirmed the diagnosis of leptomenigeal glioblastomatosis. The use of immunohistochemistry is helpful in confirming CSF cytologic diagnosis in patients with primary leptomeningeal glioblastomatosis.

• Journal of Soil and Groundwater Environment
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• v.19 no.4
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• pp.12-22
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• 2014

This study evaluated the pattern of groundwater fluctuation in cyrstalline rock using time series and factor analyses. From the results, groundwater level for the 18 wells was classified into 4 types reflecting the hydrogeological properties and rainfall event. Type 1 (DB1-5, DB1-6, DB2-2, KB-10, KB-13) was significantly influenced by groundwater flow through water-conducting features, whereas type 2 (DB1-3, DB1-7, KB-1~KB-3, KB-7, KB-11, KB-14, KB-15) was affected by minor fracture network as well as rainfall event. Type 3 (DB1-1, DB1-2) was mainly influenced by surface infiltration of rainfall event. Type 4 (DB1-8, KB-9) was reflected by the irregular variation of groundwater level caused by anisotropy and heterogeneity of crystalline rock.

• Journal of Veterinary Clinics
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• v.41 no.1
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• pp.54-59
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• 2024

A 12-year-old female small-clawed Asian otter (Anoyx cinereus) with a one-week history of anorexia, chills, and abdominal distension was found dead. Grossly, yellowish-brown turbid fluids accumulated in abdominal cavity of the otter, and yellowish thread-like fibrinous materials were found on the surface of abdominal organs. Several variable sized yellowish-white crystalloids were scattered on the medullary space of kidneys. Histologically, diffuse serositis (peritonitis) characterized by the fibrinous exudates, thickened serosal capsule and the swelling of mesothelial cells were observed in the serosa of liver, spleen, stomach, and intestine. Multifocal necrosis, hemorrhage, infiltration of macrophage, and brown pigments were presented in the liver. Isolated bacteria from ascites and fibrinous materials in abdominal visceral surface were white, smooth and convex with characteristic mousy odor on blood agar plate. These bacteria were confirmed as Pasteurella (P.) multocida type A by polymerase chain reaction analysis. Based on the gross examination, histopathologic findings and bacterial experiments, this otter was diagnosed as severe peritonitis associated with P. multocida and necrotic hepatitis.

• Korean Journal of Materials Research
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• v.9 no.3
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• pp.315-321
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• 1999

Metal matrix composites have been extensively studied because of their excellent characteristics for structural application. $Al_2O_3$ and SiC have been used as a common reinforcement owing to their good mechanical properties. However the manufacturing cost of these ceramic reinforcement is expensive, so the use of the composites has been restricted to special purposes. In this study, we tested the application possibility as a reinforcement of $Al_2O_3$-TiC powder synthesized by SHS(Self-propagating High-temperature Synthesis) process to Al alloy matrix composite. Also, $Al_2O_3$ short fibers were added with the synthesized powders in order to apply to the Al matrix hybrid composites. Squeeze infiltration casting process was used to make the composite with 25vol% of reinforcement. Microstructure and crystal structure were examined by SEM, OM and XRD, also the mechanical properties were studied by the compressive test and wear test.

• The Journal of Korean Academy of Prosthodontics
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• v.35 no.1
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• pp.221-243
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• 1997

The objective of this study was to characterize the mechanical properties of $Y_{2}O_{3}$-containing glass infiltrated ceramic core material, which was made by pressureless powder packing method. A pure alumina powder with a grain size of about $4{\mu}m$ was packed without pressure is silicon mold to form a bar shaped sample, and applied PVA solution as a binder. Samples were sinterd at $1350^{\circ}C$ for 1 hour. After cooling, $Y_{2}O_{3}$-containing glass($SiO_{2},\;Y_{2}O_{3},\;B_{2}O_{3},\;Al_{2}O_{3}$, ect) was infiltrated to the sinterd samples at $1300^{\circ}C$ for 2 hours and cooled. Six different proportions $Y_{2}O_{3}$ of were used to know the effect of the mismatch of the thermal expansion coefficient between alumina powder and glass. The samples were ground to $3{\times}3{\times}30$ mm size and polished with $1{\mu}m$ diamond paste. Flexural strength, fracture toughness, hardness and other physical properties were obtained, and the fractured surface was examined with SEM and EPMA. Ten samples of each group were tested and compared with In-Ceram(tm) core materials of same size made in dental laboratory. The results were as follows : 1. The flexural strengths of group 1 and 3 were significantly not different with that of In-Ceram, but other experimental groups were lower than In-Ceram. 2. The shrinkage rate of samples was 0.42% after first firing, and 0.45% after glass infiltration. Total shrinkage rate was 0.87%. 3. After first firing, porosity rate of experimental groups was 50%, compared with 22.25% of In-Ceram. After glass infiltration, porosity rate of experimental groups was 2%, and 1% in In-Ceram. 4. There was no statistical difference in hardness between two materials tested, but in fracture toughness, group 2 and 3 were higher than In-Ceram. 5. The thermal expansion coefficients of experimental groups were varied to $4.51-5.35{\times}10^{-6}/^{\circ}C$ according to glass composition, also the flexural strengths of samples were varied. 6. In a view of SEM, many microparticles about $0.5{\mu}m$ diameter and $4{\mu}m$ diameter were observed in In-Ceram. But in experimental group, the size of most particles was about $4{\mu}m$, and a little microparticles was observed. The results obtained in this study showed that the mismatch of the thermal expansion coefficients between alumina powder and infiltrated glass affect the flexural strength of alumin/glass composite. The $Y_{2}O_{3}$-containing glass infiltrated ceramic core made by powder packing method will takes less time and cost with sufficient flexural strength similar to all ceramic crown made with slip casting technique.

• Clinical and Experimental Pediatrics
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• v.51 no.7
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• pp.760-765
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• 2008

Paragonimiasis is a parasitic infection that occurs following the ingestion of infectious Paragonimus metacercariae from crabs or crayfish. Pulmonary paragonimiasis is the most common clinical manifestation of this infection, but several ectopic paragonimiasis cases have also been reported. Among them, cases of subcutaneous paragonimiasis are rare, especially in children. We report a case of subcutaneous paragonimiasis of the right abdominal wall with pleural effusion with hepatic involvement and without abnormal pulmonary infiltration in a boy aged 2 years and 5 months. He had eaten soybean sauce-soaked freshwater crabs (kejang) 6 months prior to complaining of right abdominal wall distension. On evaluation, right pleural effusion without abnormal pulmonary infiltration was detected, as well as blood eosinophilia, an elevated serum IgE level, pleural fluid eosinophilia and a positive enzyme-linked immunosorbent assay that detected P. westermani antibody in the serum. Thoracentesis, praziquantel administration, and excision of subcutaneous lesions were performed. After treatment, the eosinophil count and serum IgE level were decreased, and the subcutaneous lesions did not recur. The frequency of paragonimiasis has decreased recently, but it is still prevalent in Korea. Paragonimiasis should be suspected if pleural fluid eosinophilia is associated with blood hypereosinophilia and a high level of serum IgE; however clinicians should obtain a thorough history of travel and food habits.

• Journal of the Korean Ceramic Society
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• v.38 no.9
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• pp.799-805
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• 2001

Two commercial alumina powders having different particle size of $0.5{\mu}m$ and 3${\mu}$m were presintered at 1120$^{\circ}$C for 2h and then lanthanum aluminosilicate glass was infiltrated at 1100$^{\circ}$C for up to 4h to obtain the densified glass-alumina composites. The effect of alumina particle size on packing factor, microstructure, wetting, porosity and pore size, and mechanical properties of the composite was investigated. The optimum mechanical properties and compaction behavior were observed for the 3${\mu}$m alumina particle dispersed composite. The 3${\mu}$m alumina particle size and distribution for he preform were within 0.1 to 48${\mu}$m and bimodal and random orientation. The strength and the fracture toughness of the composite having 3${\mu}$m alumina particles were 519MPa and $4.5MPa{\cdot}m^{1/2}$, respectively.

• Journal of Periodontal and Implant Science
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• v.38 no.1
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• pp.51-58
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• 2008

Purpose: In dental clinical fields, various periodontal membranes are currently used for periodontal regeneration. The periodontal membranes are categorized into two basic types: resorbable and non-resorbable. According to the case, clinician select which membrane is used. Comparing different membranes that are generally used in clinic is meaningful. For this purpose, this study evaluates histological effects of various membranes in canine one wall intrabony defect models and it suggest a valuation basis about study model. Material and Method: The membranes were non-resorbable TefGen $Plus^{(R)}$, resorbable Gore Resolut $XT^{(R)}$ and resorbable $Osteoguide^{(R)}$. One wall intrabony defects were surgically created at the second and the mesial aspect of the fourth mandibular premolars in either right or left jaw quadrants in two dogs. The animals were euthanized 8 weeks post-surgery when block sections of the defect sites were collected and prepared for histological evaluation. Results: 1. While infiltration of inflammatory cells were observed in control, TefGen $Plus^{(R)}$ and Gore Resolut $XT^{(R)}$, it was not observed in $Osteoguide^{(R)}$. 2. TefGen $Plus^{(R)}$ had higher integrity than others and $Osteoguide^{(R)}$ was absorbed with folding shape. Gore Resolut $XT^{(R)}$ was divided everal parts during resorbtion and it was also absorbed from inside. 3. Quantity of new bone and new cementum was not abundant in all membranes. 4. For histologic evaluation of membranes we should consider infiltration of inflammatory, migration of junctional epithelium, integrity of membrane, quantity of new bone and new cementum, connective tissue formation and aspect of resorption. Conclusion: This histologic evaluation suggests that $Osteoguide^{(R)}$ provides periodontal regenerative environment with less inflammatory state. It is meangful that this study model suggests a valuation basis about other study model.

• Journal of Korea Foundry Society
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• v.14 no.3
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• pp.240-247
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• 1994

TiC particulate reinforced magnesium matrix composites were fabricated by melt stirring method. The effect of alloying elements on TiC particulate dispersion into molten magnesium and mechanical properties were investigated. The incorporation time is defined as the time required for dispersion of solid particles into molten metal. The incorporation time of TiC particles into molten pure magnesium was remarkably shorter and the particulated dispersion was more uniform than that of pure aluminum which was reported previously. The incorporation time was, prolonged by the addition of Al, Bi, Ca, Ce, Pb, Sn or Zn. The tensile strength increased and elongation decreased by the addition of Cu or Sn into the matrices and composites. Although, the tensile strength of the matrices and composites increased by alloying with Ca or Ce, the maximum elongation was observed at a content of about 1% for the matrices. By alloying with Zn, the tensile strength increased for the matrices and composites, but the elongation of the matrices increased. The pure magnesium and its alloy matrix composites reinforced with 20vol% TiC have the tensile strength of about 400MPa. This value is compared with the tensile strength of SiC whisker reinforced magnesium matrix composites fabricated by liquid infiltration method at the same volume fraction. There fore, the melt strirring method which has the advantages of simple process is considered to be efficient in fabricating magnesium matrix composites.