• Transactions of the Korean Society of Automotive Engineers
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• v.15 no.3
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• pp.166-173
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• 2007

A numerical study was conducted to have the effect of $CO_2$ addition to fuel on the chemical reaction mechanism with the change of the initial concentration of $CO_2$ and the axial velocity gradient. From this study, it was found that there were two serious effects of $CO_2$ addition on a non-premixed flame ; a diluent effect by the reactive species reduction and chemical effect of the breakdown of $CO_2$ by the third-body collision and thermal dissociation. Especially, the chemical effect was serious at the lower velocity gradient of the axial flow. It was certain that the mole fraction profile of $CO_2$ was deflected and CO was increased with the initial concentration of $CO_2$. It was also ascertained that the breakdown of $CO_2$ would cause the increasing of CO mole fraction at the reaction region. It was also found that the addition of $CO_2$ did not alter the basic skeleton of $H_2-O_2$ reaction mechanism, but contributed to the formation and destruction of hydrocarbon products such as HCO. The conversion of CO was also suppressed and $CO_2$ played a role of a dilution in the reaction zone at the higher axial velocity gradient.

• Korean Journal of Veterinary Research
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• v.57 no.1
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• pp.59-61
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• 2017

A 15-year-old castrated mixed breed dog presented due to a 5-month history of cough and difficulty in ambulation. Necropsy showed multiple periosteal and intramedullary infiltrative masses in the appendicular skeleton. In addition, single and multiple neoplastic nodules were observed in several organs, including the lungs, liver, kidney, and heart. Microscopically, several skeletal neoplastic masses and nodules in the parenchymal organs revealed similar changes. The neoplastic cells were spindle- to polygonal-shaped with prominent osteoid production and occasional cartilaginous and bone formation. Based on the gross findings and histopathology results, the case was diagnosed as multicentric osteosarcoma with systemic metastases.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.465-465
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• 2008

Conjugated polymers have attracted much scientific and technological research interest during the past few decades because of their potential use such as polymer light-emitting diodes (PLEDs).1,2 Particularly, lots of phenylene-based polymers such as polyfluorene and its derivatives have been synthesized because of their high photoluminescence quantum efficiencies and thermal stabilities. However, troublesome long wavelength emission in polymer film of polyfluorenes on heating during device formation or operation has been the crucial problem for practical applications. The source of the long wavelength emission was initially believed to be solely due to excimer emission as a result of polymer aggregation. It has also recently been correlated with emissions from ketonic defects in the fluorene units. Many efforts have been made to reduce the tendency to red-shifted emission. Here, we report for the first time the design and synthesis of novel 9,9-spiro bifluornene-based polymers containing heteroatoms such as N, S in its molecular skeleton. Especially, the 9,9-spiro bifluornene-based polymers containing N atom showed stable blue electroluminescence, which did not show spectral change upon thermal annealing.

• Archives of Craniofacial Surgery
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• v.20 no.2
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• pp.130-133
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• 2019

Ehlers-Danlos syndrome (EDS) is an inherited disorder of collagen biosynthesis and structure, characterized by skin hyperextensibility, joint hypermobility, aberrant scars, and tissue friability. Besides the skin, skeleton (joint) and vessels, other organs such as the eyes and the intestine can be affected in this syndrome. Accordingly, interdisciplinary cooperation is necessary for a successful treatment. Three basic surgical problems are arising due to an EDS: decreased the strength of the tissue causes making the wound dehiscence, increased bleeding tendency due to the blood vessel fragility, and delayed wound healing period. Surgery patients with an EDS require an experienced surgeon in treating EDS patients; the treatment process requires careful tissue handling and a long postoperative care. A surgeon should also recognize whether the patient shows a resistance to local anesthetics and a high risk of hematoma formation. This report describes a patient with a wide open wound on the foot dorsum and delayed wound healing after the primary approximation of the wound margins.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.50 no.2
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• pp.111-118
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• 2024

A key component of wound healing is epithelialization, which involves the proliferation and migration of epidermal keratinocytes surrounding the wound. Increasing cortisol, a stress hormone, is known to slow the healing process by inhibiting cell proliferation and migration. This study aims to develop an ingredient that can promote delayed wound healing by cortisol through a combination of Centella asiatica (C. asiatica), known for its excellent wound healing effect, and Rosamarinus officinalis (R. officinalis) leaf known for their antipsychotic effect. R. officinalis leaf extract was found to inhibit the activity of 11β-HSD1, an enzyme involved in the production of cortisol. A combination of C. asiatica and R. officinalis leaf extracts (AlfaCalm) was found to enhance cortisol induced delayed keratinocyte migration to a greater extent than C. asiatica extract. AlfaCalm enhanced the expression of CDC42 and the formation of filopodia, which are crucial for the relaxation of the actin skeleton. These results suggest that AlfaCalm can be used as an effective wound healing material in stress condition.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.2C
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• pp.109-117
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• 2010

Gas hydrate dissociation can generate large amounts of gas and water in gas hydrate bearing sediments, which may eventually escape from a soil skeleton and form voids within the sediments. The loss of fine particles between coarse particles or collapse of cementation due to water flow during heavy or continuous rainfall may form large voids within soil structure. In this study, the effect of void formation resulting from gas hydrate dissociation or loss of some particles within soil structure on the strength of soil is examined. Glass beads with uniform gradation were used to simulate a gas hydrate bearing or washable soil structure. Glass beads were mixed with 2% cement ratio and 7% water content and then compacted into a cylindrical sample with five equal layers. Empty capsules for medicine are used to mimic large voids, which are bigger than soil particle, and embedded into the middle of five equal layers. The number, direction, and length of capsules embedded into each layer vary. After two days curing, a series of unconfined compression tests is performed on the capsule-embedded cemented glass beads. Unconfined compressive strength of cemented glass beads with capsules depends on the volume, direction and length of capsules. The volume and cross section formed by voids are most important factors in strength. An unconfined compressive strength of a specimen with large voids decreases up to 35% of a specimen without void. The results of this study can be used to predict the strength degradation of gas hydrate bearing sediments in the long term after dissociation and loss of fine particles within soil structure.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.20 no.2
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• pp.91-96
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• 1998

Surgical resection of tumors in the maxillofacial region sometimes results in extended defects of soft and hard tissue that frequently causes aesthetic, functional and especially mental damages. It is essential for patients with such facial defects to reduce the scar and maxillofacial asymmetry. To attain esthetic facial appearance after hemimaxillectomy, we devise a new design, so called 'IOIO Incision' (InfraOrbital-IntraOral incision). The new approach is established on infraorbital region to expose maxillofacial skeleton in aspect of face. And the other incision is designed on intraoral region. The IOIO incision provide excellent aesthetic result after hemimaxillectomy, because of reduced minimal facial scar contraction. Maxillofacial surgeons are used to designing Weber-Fergusson incision in resection of maxillofacial tumors, but disadvantages of the incision were large scar and asymmetry of face. To improve theses problem, we attempted IOIO Incision.. For correct osteotomy of posterolateral wall of maxillary sinus, 1. Fenestra formation on zygomatic body for easily access of reciprocating saw to posterolateral wall of maxillary sinus. 2. To achieve better visual field in posterolateral aspect of maxilla, fat tissue is removed from infratemporal fossa. This new, versatile procedure can be used for benign and malignant lesions of the maxillary area. We introduce cases with review of literatures.

• Convergence Security Journal
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• v.11 no.4
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• pp.3-9
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• 2011

On health information network architecture, traffic along the path of traffic and security, blocking malicious code penetration is performed. The medical information system network security infrastructure study, which was whether to be designed based on the structure and methodology is designed to develop the security features. Health informati on system's functionality and capabilities framework for infrastructure is the backbone and structure. The design fea tures a framework for the overall network structure formation of the skeleton and forms the basic structure of the security methodology. Infrastructure capabilities to build the framework and the application functionality is being implemented. Differentiated in accordance with security zones to perform security functions and security mechanisms that operate through this study is to present. u-Healthcare future advent of cloud computing and a new health information environment, the medical information on the preparation of this study is expected to be utilized for security.

• Economic and Environmental Geology
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• v.32 no.3
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• pp.217-225
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• 1999

Nine cauldrons have been recognized in the PVD (Pusan- Taegu Volcano-tectonic Depression) zone covering an area of nearly 7,000 $km^{2}$. They form characteristic landscape features with various mountains in the southeastern Kyongsang basin. Economically important ore deposits are also developed either in the ring fracture zone or the central pluton within the resurgent cauldrons or in the marginal area of the PVD, suggesting that these cauldrons played a major role in the distribution of ore deposits in the southeastern Kyongsang basin. Furthermore, the cauldron subsidences were more frequent with the more felsic volcano-plutonic complex, possibly indicating that the amounts of water and volatile components also acted as a controlling factor to cause the caldera subsidence and to concentrate the ore-forming elements in economic concentrations. The review of the relationship and variations of ore mineralization and cauldron subsidence is rather sketchy, but it provides a skeleton to carry out more detailed and quantitative studies related to temporal and spatial relationships between each cauldron subsidence accompanying its own ore mineralization. In the southeastern Kyongsang basin, additional calderas and associated ore deposits undoubtedly can be discovered through future detailed studies. The concept that cauldron subsidence are an important control for the formation of ore deposits will appear to be vindicated.

• Korean Journal of Veterinary Research
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• v.50 no.2
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• pp.85-91
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• 2010

The large amount of tissue culture medium (TCM), which contains some of the active secretory components of Korean wild ginseng (KWG; Panax ginseng) such as saponins, is usually discarded after harvest of KWG. The present study was aimed to investigate the efficacy of oral administration of the TCM-KWG on growth performance and diseases resistance in broiler chickens. A day old broiler chickens randomized in 6 groups (n = 60/groups) were administered orally with 0, 2, 4, 8, 16 and 32 mL/L TCMKWG through drinking water for 5 weeks and examined the change of weight gain, feed intake and blood components. Also, five weeks old broiler chickens (n = 15/groups) were challenged orally with Salmonella (S.) gallinarum and investigated the mortality in broiler chickens. An average weight gain and feed intake significantly didn't change in TCM-KWG administration groups as compared to control group. The concentration of calcium (Ca), phosphate (Pi) and potassium (K) in serum were increase by TCM-KWG administration in broiler chickens. We also found that oral administration of TCM-KWG through drinking water significantly reduced the mortality in broiler chickens experimentally infected with virulent S. gallinarum. The results of this study indicated that TCM-KWG administration may elevate the resistance on disease and improved the skeleton formation and body homeostasis of chickens, and TCM-KWG can be used as a cost-effective and environmentally alternative additives to control of the disease and growth.