• Journal of the Korean Mathematical Society
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• v.56 no.4
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• pp.1083-1112
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• 2019

In this paper, we present and analyze a cell-centered collocated finite volume scheme for incompressible flows to compute solutions simultaneous to Stokes and Darcy equations by applying a pressure jump stabilization term to avoid locking. We prove that the new stabilized FV formulation satisfies a discrete inf-sup condition and error estimates for both problems. Finally, we present some numerical examples confirming this analysis.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.29 no.9 s.240
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• pp.1049-1056
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• 2005

A conservative pressure-based finite-volume numerical method has been developed for computing flow and heat transfer by using an unstructured grid system. The method admits arbitrary convex polyhedra. Care is taken in the discretization and solution procedures to avoid formulations that are cell-shape-specific. A collocated variable arrangement formulation is developed, i.e. all dependent variables such as pressure and velocity are stored at cell centers. Gradients required for the evaluation of diffusion fluxes and for second-order-accurate convective operators are found by a novel second-order accurate spatial discretization. Momentum interpolation is used to prevent pressure checkerboarding and the SIMPLE algorithm is used for pressure-velocity coupling. The resulting set of coupled nonlinear algebraic equations is solved by employing a segregated approach, leading to a decoupled set of linear algebraic equations fer each dependent variable, with a sparse diagonally dominant coefficient matrix. These equations are solved by an iterative preconditioned conjugate gradient solver which retains the sparsity of the coefficient matrix, thus achieving a very efficient use of computer resources.

• Carbon letters
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• v.1 no.3_4
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• pp.170-177
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• 2001

Lithium intercalated carbon (LIC) are basically employed as an anode for currently commercialized lithium secondary batteries. However, there are still strong interests in modifying carbon surface of active materials of the anode because the amount of irreversible capacity, charge-discharge capacity and high rate capability are largely determined by the surface conditions of the carbon. In this study, the carbonaceous materials were coated with tin oxide and copper by fluidized-bed chemical vapor deposition (CVD) method and their coating effects on electrochemical characteristics were investigated. The electrode which coated with tin oxides gave the higher capacity than that of raw material. Their capacity decreased with the progress of cycling possibly due to severe volume changes. However, the cyclability was improved by coating with copper on the surface of the tin oxides coated carbonaceous materials, which plays an important role as an inactive matrix buffering volume changes. An impedance on passivation film was decreased as tin oxides contents and it resulted in the higher capacity.

• Advances in Traditional Medicine
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• v.7 no.4
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• pp.426-435
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• 2007

The present study was designed to determine the antitumor and antioxidant properties of methanol extract from the root of Galega purpurea (Papilionaceae) (MEGP) against Ehrlich Ascites Carcinoma (EAC) bearing Swiss albino mice. Acute and short-term toxicity studies were performed initially in order to ascertain the safety of MEGP. The effect of MEGP on the growth of transplantable murine tumor, life span of EAC bearing hosts and simultaneous alterations in the hematological profile and liver biochemical parameters (lipid peroxidation, antioxidant enzymes) were estimated. The MEGP showed decrease in tumor volume, packed cell volume and viable cell count and increases the nonviable cell count and mean survival time thereby increasing life span of EAC tumor bearing mice. Hematological profile reverted to more or less normal levels in extract treated mice. Treatment with MEGP decreased the levels of lipid peroxidation and increased the levels of glutathione, superoxide dismutase and catalase. The results suggested that the methanol extract of Galega purpurea root exhibited antitumor effect by modulating lipid peroxidation and augmenting antioxidant defense system in EAC bearing mice.

• Atmosphere
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• v.21 no.3
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• pp.243-256
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• 2011

This paper presents the development of new algorithm for identifying and tracking the convective cells in three dimensional reflectivity fields in Cartesian coordinates. First, the radar volume data in spherical coordinate system has been converted into Cartesian coordinate system by the bilinear interpolation. The three-dimensional convective cell has then been identified as a group of spatially consecutive grid points using reflectivity and volume thresholds. The tracking algorithm utilizes a fuzzy logic with four membership functions and their weights. The four fuzzy parameters of speed, area change ratio, reflectivity change ratio, and axis transformation ratio have been newly defined. In order to make their membership functions, the normalized frequency distributions are calculated using the pairs of manually matched cells in the consecutive radar reflectivity fields. The algorithms have been verified for two convective events in summer season. Results show that the algorithms have properly identified storm cells and tracked the same cells successively. The developed algorithms may provide useful short-term forecasting or nowcasting capability of convective storm cells and provide the statistical characteristics of severe weather.

• Journal of Hydrogen and New Energy
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• v.22 no.5
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• pp.585-591
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• 2011

This study has focused on the development of high performance membrane-electrode assemblies (MEAs) fabricated by decal method for proton exchange membrane fuel cell (PEMFC). To study the effect of ionomer contents on performance, we fabricated MEAs with several electrodes which were prepared by varying the quantity of ionomer from 20 wt.% to 45 wt.% in catalyst layer. The MEA performance was obtained through single cell test. The MEA prepared from electrode with 25wt.% of ionomer showed the best performance. We evaluated the surface area and pore volume of electrode with BET. We found that the surface area and pore volume in electrode decreased rapidly at the electrode with 40wt.% of ionomer in catalyst layer. MEA was fabricated by roll laminator machine and the roll laminating conditions for the preparation of MEA, such as laminating press, temperature and speed, were optimized. The MEA performance is not affected by laminating temperature and speed, but roll laminating press have a great effect on MEA performance.

• Journal of Veterinary Clinics
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• v.19 no.1
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• pp.55-60
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• 2002

The Allium tuberosum is a perennial herb. From the ancient times, it has been used for food or medical purpose. Allium tuberosum is widely distributed in Korea, China, Japan and other countries. As herbal medicine, the Allium tuberosum has medical effects on lumbago, sthenia, diuresis, nocturia, hematemesis, anemia, haemorrhoid, hiccups, diarrhea, eczema, sunstroke, pollution and so on. Recently, the Allium tuberosum has been studied on its components, anti-microorganism action, anti-fungal action, anti-arteriosclerosis action, anti-cancer action. However, there has not been any study on hematological effect of allium tuberosum extract on the blood in large dogs whereas the effects of excess garlic and onion on the blood of cattle, horses, dogs, cats and sheep has been reported by many researchers. Thus, this study was performed to observe the hematological effect of excessive Allium tuberosum extract administrated in large dogs. 1. The Red Blood Cell(R3C) count was significantly decreased(p<0.05), Packed Cell Volume (PCV) count were significantly decreased(P<0.05), and Reticulocyte count was significantly increased(p<0.05) 2. The White Blood Cell(WBC) count was significantly increased(p<0.05).3. The Hemoglobin concentration was significantly decreased(p<0.05) and Mean Corpuscular Hemoglobin Concentration (MCHC) was increased. and Mean Corpuscular Volume(MCV) was significantly increased.(p<0.05). 4. The Reduced glutathione(GSH) and Met-Hemoglobin were significantly increased (p<0.05).

• Imaging Science in Dentistry
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• v.52 no.2
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• pp.123-131
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• 2022

Purpose: The aim of this study was to characterize the cone-beam computed tomographic (CBCT) imaging features of central giant cell granuloma (CGCG) of the jawbone. Materials and Methods: This study retrospectively reviewed 26 CBCT studies of histologically proven cases of CGCG during a period of 20 years, from 1999 to 2019. Patients' demographic data were recorded, and radiographic features were assessed (location, border, cortication, appearance of the internal structure, locularity, septation, expansion, cortical perforation, effects on surrounding tissue, whether the lesion crossed the midline, and lesion volume). Results: In this study, CGCGs were seen almost twice as often in the mandible than in the maxilla, and 64.7% of mandibular lesions involved the anterior region. Only 26.9% of lesions crossed the midline, a feature that was considered characteristic of CGCG. Furthermore, 65.4% of lesions were unilocular and 34.6% were multilocular. The correlation between a lesion's size and its locularity was statistically significant, and larger lesions showed a multilocular appearance. The mean volume of multilocular lesions was greater than that of unilocular lesions. Conclusion: CGCGs showed variable radiographic features on CBCT, and this imaging modality is highly effective at demonstrating the radiographic spectrum and lesional extent of CGCGs in the jawbone.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.11
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• pp.1524-1528
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• 2006

A total of 437 animals, comprising lambs aged between 3 and 12 months and adults of either sex of Muzaffarnagari sheep maintained at the Central Institute for Research on Goats, Makhdoom, Farah, Mathura, India were screened to assess the prevalence of Haemonchus contortus infection following natural infection and to identify the various factors affecting faecal egg count (FEC) and packed cell volume (PCV) of ewes and their genetic control. The relationships between FEC, PCV and body weight were also estimated. The prevalence rate for H. contortus infection in the flock under study was 15.7% indicating much lower occurrence of worm infection in lambs up to one year of age. On the other hand, a large proportion i.e., 67.7% of sheep was refractive to natural H. contortus infection. The random effect of sire significantly contributed (p<0.01) variation in log-transformed FEC (LFEC) of ewes. The season of birth had a significant (p<0.01) effect on LFEC of ewes. The lactating ewes had significantly (p<0.01) higher faecal egg counts compared to dry and pregnant ewes. The linear regression effects of the age of ewes on LFEC of animals were significant (p<0.01) in the present study. The heritabilities of LFEC, PCV and body weights of ewes during the course of infection were moderate to high in magnitude and ranged from 0.24 to 0.47. The LFEC of ewes was significantly (p<0.05) and negatively correlated with PCV at both genetic and phenotypic level. The genetic and phenotypic relationships between LFEC and body weights of ewes were -0.26 and -0.06 for this breed. The genetic correlation of PCV and body weight of ewes was positive and high (0.58) and statistically significant (p<0.05) but it was negatively correlated (-0.01) with body weight at the phenotypic level.

• Radiation Oncology Journal
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• v.33 no.2
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• pp.117-125
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• 2015

Purpose: To investigate the relationship between early treatment response to definitive chemoradiotherapy (CRT) and survival outcome in patients with limited stage small cell lung cancer (LS-SCLC). Materials and Methods: We retrospectively reviewed 47 patients with LS-SCLC who received definitive CRT between January 2009 and December 2012. Patients were treated with systemic chemotherapy regimen of etoposide/carboplatin (n = 15) or etoposide/cisplatin (n = 32) and concurrent thoracic radiotherapy at a median dose of 54 Gy (range, 46 to 64 Gy). Early treatment volume reduction rate (ETVRR) was defined as the percentage change in gross tumor volume between diagnostic computed tomography (CT) and simulation CT for adaptive RT planning and was used as a parameter for early treatment response. The median dose at adaptive RT planning was 36 Gy (range, 30 to 43 Gy), and adaptive CT was performed in 30 patients (63.8%). Results: With a median follow-up of 27.7 months (range, 5.9 to 75.8 months), the 2-year locoregional progression-free survival (LRPFS) and overall survival (OS) rates were 74.2% and 56.5%, respectively. The mean diagnostic and adaptive gross tumor volumes were 117.9 mL (range, 5.9 to 447 mL) and 36.8 mL (range, 0.3 to 230.6 mL), respectively. The median ETVRR was 71.4% (range, 30 to 97.6%) and the ETVRR >45% group showed significantly better OS (p < 0.0001) and LRPFS (p = 0.009) than the other group. Conclusion: ETVRR as a parameter for early treatment response may be a useful prognostic factor to predict treatment outcome in LS-SCLC patients treated with CRT.