• Journal of Korean Institute of Industrial Engineers
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• v.22 no.3
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• pp.517-532
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• 1996

The area and time-dependent vehicle scheduling problem(ATVSP) is a generalization of the vehicle scheduling problem in which the travel speed between two locations depends on the passing areas and time of day. We propose a simple model for estimating area and time-dependent travel speeds in the ATVSP that relieves much burden for the data collection and storage problems. A mixed integer nonlinear programming formulation of the ATVSP is presented. We also propose three heuristics for the ATVSP, developed by extending and modifying existing heuristics for conventional vehicle scheduling problems. The results of computational experiments demonstrate that the proposed estimation model performs well and the saving method is the best among the three heuristics.

• Journal of Veterinary Clinics
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• v.21 no.2
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• pp.187-190
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• 2004

A mixed case of multiple sebaceous gland adenoma and perianal gland adenoma was found in a 11-year-old male Shih Tzu dog. Grossly, many masses less than 1 cm in diameter of back skin and single red-brown mass about 0.5 cm in diameter of inner ear were noted. In addition one of light-pink mass 5 cm in diameter was presented in the anus. All of the masses were well demarcated and dome-shaped or papillated nodules. Histologically, the mass from back and ear were composed with multiple irregular shaped or sized lobules of sebaceous glands. Masses were containing mostly mature sebaceous cells and multifocal cystic degeneration with acellular and bright eosinophilic materials. And the mass from peri-anal area was well-circumscribed and composed of broad, anastomosing trabeculae of well-differentiated hepatoid cells. There were very low mitotic figures in all masses. Based on these results, this case was diagnosed as the multiple sebaceous gland adenoma and perianal gland adenoma.

• Journal of Wetlands Research
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• v.15 no.3
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• pp.357-366
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• 2013

This study investigates to explain preference heterogeneity of respondents for economic valuation in washland of Upo wetland using Mixed Logit Model and Latent Class Model. Mixed Logit Model showed respondent heterogeneity in the attributes of wetland area and funds as well as some alternatives violated IIA assumption. 2-class Latent Class Model for respondents were used to explain the sources of the heterogeneity. Class 1 respondents who are located relatively close to Upo wetland had more experience and knowledge of Upo wetland and better understood the information suggested in the questionnaire than class 2 respondents in mostly metropolitan area of Seoul, Incheon.

• Atmosphere
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• v.27 no.3
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• pp.317-329
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• 2017

Ocean mixed layer (OML) depth affects diurnal cycle of sea surface temperature (SST) induced by change of solar radiation absorption and heat budget in ocean. The diurnal SST variation can lead to convection over the ocean, which can impact on localized precipitation both over coastal and inland. In this study, we investigate the OML characteristics affecting the diurnal cycle of SST for the Korean Peninsula and surrounding areas. To analyze OML characteristics, HYCOM oceanic mixed layer depth (MLD) and wind field at 10 m from ERA-interim during 2008~2016 are used. In the winter, MLD is deeply formed when the strong wind field is located on perpendicular to continental slope over deep seafloor areas. Besides, cooling SST-induced vertical mixing in OML is reinforced by dry cold air originated from Siberia. The OML in summer is shallowly distributed about 20 m. In order to estimate the impact of OML model in high resolution NWP model, four experimental simulations are performed. At this time, the prognostic scheme of skin SST is applied in NWP to simulate diurnal SST. The simulation results show that CNTL (off-OML) overestimates diurnal cycle of SST, while EXPs (on-OML) indicate similar results to observations. The prediction performance for precipitation of EXPs shows improvement compared with CNTL over coastal as well as inland. This results suggest that the application of the OML model in summer season can contribute to improving the prediction for performance of SST and precipitation over coastal area and inland.

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.329-329
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• 2022

Accurate characterization of terrestrial precipitation variation from high spatial resolution satellite sensors is beneficial for urban hydrology and microscale agriculture modeling, as well as natural disasters (e.g., urban flooding) early warning. However, the widely-used top-down approach for precipitation retrieval from microwave satellites is limited in several hydrological and agricultural applications due to their coarse spatial resolution. In this research, we aim to apply a novel bottom-up method, the parameterized SM2RAIN, where precipitation can be estimated from soil moisture signals based on an inversion of water balance model, to generate high spatial resolution terrestrial precipitation estimates at 0.01º grid (roughly 1-km) from the C-band SAR Sentinel-1. This product was then tested against a common reanalysis-based precipitation data and a domestic rain gauge network from the Korean Meteorological Administration (KMA) over central South Korea, since a clear difference between climatic types (coasts and mainlands) and land covers (croplands and mixed forests) was reported in this area. The results showed that seasonal precipitation variability strongly affected the SM2RAIN performances, and the product derived from separated parameters (rainy and non-rainy seasons) outperformed that estimated considering the entire year. In addition, the product retrieved over the mainland mixed forest region showed slightly superior performance compared to that over the coastal cropland region, suggesting that the 6-day time resolution of S1 data is suitable for capturing the stable precipitation pattern in mainland mixed forests rather than the highly variable precipitation pattern in coastal croplands. Future studies suggest comparing this product to the traditional top-down products, as well as evaluating their integration for enhancing high spatial resolution precipitation over entire South Korea.

• Journal of Korean Neurosurgical Society
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• v.30 no.6
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• pp.774-776
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• 2001

We report a 35-year old female patient with history of seizure and mass which was confirmed as a plasma cell granuloma, arising in the left parietal area. The mass appeared on magnetic resonance imaging as well circumscribed area of decreased signal that markedly enhanced with administration of the contrast. Pathologically, biopsy showed a mixed cellular population with considerable numbers of plasma cells along with eosinophils and lymphocytes and the tumors was characterized immunohistochemically by polyclonal population of lymphoid cells.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.2
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• pp.187-192
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• 2003

To evaluate the oceanographic conditions for the artificial upwelling we measured vertical stratification coefficients, current speed distribution and grain size distribution of bottom sediment in the vicinity of Gukdo and Somaemuldo near Geojedo. There were a strong stratification between surface and bottom layers in summer, the stratification was weak from autumn to winter, and the water was well mixed during winter. In summer nutrient concentration of the bottom layer was 4 times higher than that of the surface layer. Underwater currents were strong in the bottom layer. We conclude that the oceanographic conditions in the area will meet the basic requirement for the construction of artificial upwelling.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.521-524
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• 2004

The Purpose of this study is to develope the method for early recovery of the biodiversity in the oligotrophical costal area, it is important in the recovery of the biodiversity to make kelp forest grow in the concerned area. In order for it, sufficient nutrient is required as well as the proper seedbed, Hence in this study, granulated fertilizer, which contains nutrient, such as nitrogen, phosphorus and etc, is coated by cement paste, and then is mixed in to the porous concrete in order to provide seedbed and nutrient simultaneously. The physical and mechanical properties, such as water permeability, void ratio, compressive strength of porous concrete with granulated fertilizer are discussed.

• Ocean Science Journal
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• v.41 no.3
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• pp.181-189
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• 2006

Frontal areas between warm and saline waters of the Kuroshio currents and colder and diluted waters of the East China Sea (ECS) influenced by the Changjiang River were identified from the satellite thermal imagery and hydrological data obtained from the Coastal Ocean Process Experiment (COPEX) cruise during the period between March $1^{st}$ and $10^{th}$, 1997. High chlorophyll concentrations appeared in the fronts of the East China Seas with the highest chlorophyll-a concentration in the southwestern area of Jeju Island (${\sim}2.9\;mg/m^3$) and the eastern area of the Changjiang River Mouth (${\sim}2.8\;mg/m^3$). Vertical structures of temperature, salinity and density were similar, showing the fronts between ECS and Kuroshio waters. The water column was well mixed in the shelf waters and was stratified around the fronts. It is inferred that the optimal condition for light utilization and nutrients induced both from the coastal and deep waters enhances the high phytoplankton productivity in the fronts of the ECS. In addition, the high chlorophyll-a in the fronts seems to have been associated with the water column stability as well.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.28 no.1
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• pp.235-243
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• 1998

Cementifying fibroma is an odontogenic tumor of periodontal ligament origin, consisting of a proliferation of fibrous tissue that forms cementum. Cemento-ossifying fibroma, cementifying fibroma and ossifying fibroma are difficult to distinguish on clinical and radiographic exmination, and on histopathology. However, when the calcified product is represented by ovoid or curvilinear deposits, the lesion is often referred to as cementifying fibroma. Cementifying fibromas of the jaws are well-circumscribed, generally slow-growing lesions. Although most lesions appear to be limited to the tooth-bearing areas, a few have extended into the angle-ramus area or encroached on the maxillary sinus. Radiographically, the cementifying fibroma could present as a radiolucent, radiopaque or mixed density lesion, depending on the degree of maturity. We have observed two cases of cementifying fibroma occurred in the left maxillary premolar-molar area of 38-year-old woman and 35-year old man. We obtained that two cases were shown the followed results; 1. Clinically, main clinical symptom was facial swelling and pain at palpation 2. Radiographically, well-circumscribed radiolucent lesion and radiolucent lesion with radiopaqu e foci were seen on the left maxillary premolar-molar areas. Loss of lamina dura and root resorption or divergency were also seen. 3. Histopathologically, many cementum-like calcifications were observed in the hypercellular connective tissue.