• Transactions of the Korean Society of Mechanical Engineers B
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• v.23 no.8
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• pp.1040-1047
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• 1999

The characteristics of flame propagation in inert particle-laden $H_2$/Air premixed gas are numerically investigated on this study. The 2nd order TVD scheme is applied to numerical analysis of governing equations and multi-step chemical reaction model and detailed transport properties are sued to solve chemical reaction terms. Radiation heat transfer is computed by applying the finite volume method to a radiative transfer equation. The burning velocities against the mole fractions of hydrogen agree well with results performed by different workers. The inert particles play significant roles in the flame propagation on account of momentum and heat transfer between gas and particles. Gas temperature, pressure and flame propagation speed are decreased as the loading ratio of particle is increased. Also the products behind flame zone contain lots of water vapor whose absorption coefficient is much larger than that of unburned gas. Thus, the radiation effect of gas and particles must be considered simultaneously for the flame propagation in a mixture of $H_2$/Air and inert particles. As a result, it is founded that because the water vapor emits much radiation and this emitted radiation is released at boundaries as radiant heat loss as well as reabsorbed by gas and particles, flame propagation speed and flame structure are altered with radiation effect.

• Applied Chemistry for Engineering
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• v.26 no.1
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• pp.40-46
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• 2015

Microcapsules containing the suspension of conducting materials such as carbon nanotube (CNT) or polyaniline (PANI) were prepared by in-situ polymerization of melamine and formaldehyde. Stable microcapsules were prepared and the mean diameter of the observed microcapsules was in the range of $10-20{\mu}m$. The surface morphology and chemical structure of microcapsules were investigated using optical microscope (OM), scanning electron microscope (SEM), and Fourier transform infrared spectroscopy (FT-IR). The thermal properties of samples were investigated by thermogravimetric analysis (TGA). The conductivity of ruptured microcapsule containing the suspension of CNTs or PANIs in tetrachloroethylene and Isopar-G was measured. As the amount of CNTs and PANIs in the core of microcapsules increased, the measured current increased. Conductivity measurement results suggest that poly (melamine-formaldehyde) based core-shell microcapsules could be applied to self-healing electronic materials systems, where CNTs or PANIs bridge a broken circuit upon release.

• Fire Science and Engineering
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• v.27 no.6
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• pp.38-43
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• 2013

As a preliminary study to evaluate the reliability of the calculation method of fire load for residential furniture combustibles, the present study estimates the fire load considering the volume data obtained by the 3D geometrical information of combustibles and material properties based on the literature survey and sample burning test. A kitchen sink cabinet, couch and workstation were investigated for estimating its fire load and real fire test have been performed to measure total energy released from the combustibles. Based on total energy measured from real fire test, the relative error of the estimated fire load due to literature survey and measured material properties showed 6~120% and less than 20%, respectively. It shows that the estimation error of fire load are greatly affected by its material properties as well as geometrical information of combustibles and the present study will be able to contribute to accurate estimation of fire load.

• Journal of Veterinary Clinics
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• v.8 no.2
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• pp.147-152
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• 1991

Trichophyton mentagrophytes was described as a primary cause of mycotic dermatitis in two young goats housed together in a humid, ill-ventilated and unhygienic byre. The diagnosis in both the cases was established on the detection of fungal element in the skin scrapings by potassium hydroxide technique and isolation of the pathogen in pure growth on mycological medium at 30$^{\circ}C$. The lesions were found on the face of one kid and on the neck and ear of another one. Two adult goats housed in the same enclosure were found to be free from this disease. Further, there was no evidence of ringworm in the goat owner and his family members. Genetic crossing of both the isolates on modified sunflower seed medium indicated that they belonged to (―) mating type. Hair performation test revealed the keratolytic activity of both the strains of T. mentagrophytes. The public health significance and chemotherapy are also discussed. The question of source of infection could not be emphatically established.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.23 no.1
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• pp.1-10
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• 2011

Recently harbor remodeling projects are seriously considered to enhance the loading and unloading capability of old container terminals and to make decrepit ports as eco-friendly harbor and waterfront spaces in many countries. In such a case, quantitative and qualitative evaluations on concrete harbor facilities are mandatory to determine the current structural integrity condition of aged materials. Once the remodeling project is determined to be carried out, the reusability of individual structural members and facilities including caissons, cell-blocks, and tetra-pods need to be decided based on the simple and economic visual inspection and/or nondestructive testing. In this study, the systematic quantitative evaluation procedure for determining the structural integrity condition and the reusability is studied based the nondestructive testing and evaluation methods. Conventional methods including Schmidt hammer test and ultrasonicpulse velocity methods and elastic wave based methods including impact echo test and surface wave test are applied to the old harbor facilities in five different sites. The compressive tests are also carried out to determine the elastic modulus and compressive strength of concrete materials.

• The Journal of the Korean bone and joint tumor society
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• v.12 no.1
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• pp.15-22
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• 2006

Purpose: This study was designed to investigate the clinical and oncological results of giant cell tumor, treated with electrocautery as an adjuvant. Materials and Methods: We evaluated 47 giant cell tumors treated in both institution from 1989 to 2004, retrospectively. We treated all 47 cases with intralesional curettage and speed burring and followed electrocautery as an local adjuvant. Results: The mean follow up periods was 44 months and ranged from 12 to 180 months. The local recurrence occurred in 8 patients (17%) and one case lung metastasis was found. There was one case complication (septic knee) associated with electrocautery as an adjuvant. Conclusions: We thought electrocautery was feasible adjuvant treatment method of giant cell tumor, because it is very convenient technique, and the local recurrence rate was similar to any other methods.

• The Journal of the Korean bone and joint tumor society
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• v.12 no.1
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• pp.71-77
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• 2006

Chondrosarcoma is one of the most common types of primary bone sarcoma. With the exception of the mesenchymal subtype, chondrosarcomas are usually low-grade lesions and rarely show multicentricity or distant metastasis. Only rare cases of multicentric chondrosarcomas have been reported in association with Ollier's disease and Maffucci's syndrome. To our knowledge, no report has been issued of a synchronous multicentric chondrosarcoma occurrence across a joint. We experienced a 30-year-old man with a synchronous monomelic juxta-articular multicentric chondrosarcoma across a shoulder joint in the absence of pulmonary and visceral metastases. He was treated by curettage and cement filling with allograft in the acromion and wedge resection with cement filling in the proximal humerus. At the 18-month follow-up, there was no evidence of recurrence, and the patient had full range of motion without pain.

• The Journal of the Korean bone and joint tumor society
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• v.15 no.2
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• pp.151-154
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• 2009

Bronchogenic cyst is rare lesion that arises from maldevelopment of the primitive foregut, and is usually found in the lung and mediastinum. Cutaneous or subcutaneous bronchogenic cyst is rare and occur unusually in the shoulder region. We report here a case of 20-month-old boy with a bronchogenic cyst on his left shoulder region. He underwent incisional biopsy and curettage for a tender cystic mass at a department of dermatology, diagnosed as a epidermal inculsion cyst. But, additional cystic mass was palpated during wound care. MRI showed a well-defined subcutaneous cystic mass. The excised cyst was lined with pseudostratified ciliated columnar epithelium with occasional goblet cells and diagnosed as a bronchogenic cyst.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.15 no.2
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• pp.111-116
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• 1982

For the effective utilization of the fish resources in coastal regions, investigations on processing conditions of frozen-dried product, quality stability of the Product during storage, and utilization as a food material were carried out with the filefish, Navoden modestus. The processing condition was determined with the moisture content and texture of the product. The duality of the product was evaluated on chemical composition, rehydration capacity, TBA value, browning, omission test and sensory score. The conditions for the processing of frozen-dried filefish under the conditions of freezing temperature at $-10^{\circ}C$ and forced air thawing at $56{\pm}2^{\circ}C$ with a velocity of 1 m/sec were as follows : freezing temperature, $-10^{\circ}C$ : freezing time, 10 hours; thawing time, 2 hours ; and repeated number of freezing and thawing, 5 times. The yield, the condition of moisture and protein were $10.2\%,\;23.6\%\;and\;70.6\%$, respectively. The frozen-dried product packed with air and stored at room temperature showed no remarkable changes in TBA value, rehydration capacity, browning during the storage period of 90days. The frozen-dried filefish showed no remarkable differences in the taste, odor and texture, comparing with frozen-dried Alaska pollack on the market.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.29 no.2
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• pp.187-191
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• 2007

An ameloblastoma is one of the most common odontogenic tumors. Ameloblastoma is cytologically a benign tumor, but is clinically characterized by infiltrative growth and high recurrency. The treatment of ameloblastoma has been controversial. The aim of this paper is to consider effectiveness of curettage and enucleation after SSRO in the small-sized multilocular intraosseous ameloblastomas that have been treated more frequently by radical treatment. They were radiographically characterized by the cortical bone that was expanded or eroded locally and histopathologically by solid multilocular ameloblastomas. It is considered that curettage and enucleation after SSRO and long-term follow-up enable the small-sized multilocular intraosseous ameloblastomas that were characterized by almost destroyed cancellous bone and expanded cortical bone to treat minimizing facial disfigurement and masticatory dysfunction and sociopsychological impact produced by radical treatment. We recommend that the small-sized multilocular intraosseous ameloblastomas without involvement to the surrounding soft tissues be first treated by curettage and enucleation after SSRO.