• Transactions of the Korean Society of Mechanical Engineers B
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• v.34 no.2
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• pp.129-136
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• 2010

Axial piston pumps have been widely used as power sources for hydraulic systems, but studies on the fluid flow within the pump have been usually performed using 1-D analysis because of the difficulties in considering the fluid compressibility, high-speed revolution, variation of the flow rate, and complicated geometry. The goal of this study was to understand the hydraulic fluid flow within axial piston pumps by using the 3-D numerical method and the process of generating discharge pressure ripples. To improve the convergence and robustness of the simulation model, a grid system was constructed with hexahedron-type grids around the valve plate. Furthermore, we employed an empirical formula to describe the relationship between the oil density and pressure. The CFD (computational fluid dynamics) results compared well with the experimental data.

• Journal of Haehwa Medicine
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• v.16 no.1
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• pp.81-91
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• 2007

Objective : We wished to examine closely effect that Kami-KangHwalSan medicines used to atopy dermatitis disease patient get in atopy eruption control experimentally. Materials and Methods : Atopic dermatitis (AD) usually develops in patients with an individual or family history of allergic diseases, and is characterized by chronic relapsing inflammation seen specially in childhood, association with IgE hyperproduction and precipitation by environmental factors. However, the exact etiology of AD has been unclear. To further explore the pathogenesis and treatment of AD, a suitable animal model is required. We found that skin lesions, which were chnically and histologically very simlar to human AD, mite antigen-induced dermatitis on the face, neck, ears and dorsal skin of inbred NC/Nga mice. Results and Conclusion : Kami-KangHwalSan medicines controlled CD3+/CD69+, CD4+/CD25+, B220+/IgE+, and B220+/CD23+ revelation that an experiment that motive allergy immune reponse because an in vitro experiment stimulates splenocytes of a NC/Nga mouse same t1me by PWM, and interleukin-4, eotaxin 2, CCR3, TARC mRNA outturn that bear in splenocytes decreased remarkably by Kami-KangHwalSan medicines. Th1 cell and Th2 cell observe to be shifted by secretion amount of IL-4 and IFN-$\gamma$ by Kami-KangHwalSan medicines could know that Kami-KangHwalSan medicines can use usefully in allergy autoimmnune diease.

• Journal of Haehwa Medicine
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• v.16 no.1
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• pp.93-105
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• 2007

Objective : We wished to examine closely effect that Kami-JeSeubUilYeongTang medicines used to atopy dermatitis disease patient get in atopy eruption control experimentally. Materials and Methods : Atopic dermatitis (AD) usually develops in patients with an individual or family history of allergic diseases, and is characterized by chronic relapsing inflammation seen specially in childhood, association with IgE hyperproduction and precipitation by environmental factors. However, the exact etiology of AD has been unclear. To further explore the pathogenesis and treatment of AD, a suitable animal model is required. We found that skin lesions, which were clinically and histologically very similar to human AD, mite antigen-induced dermatitis on the face, neck, ears and dorsal skin of inbred NC/Nga mice. Result and Conclusion : Kami-jeseupwiryeongtang(JWRTK) medicines controlled CD3+/CD69+, CD4+/CD25+, B220+/IgE+, and B220+/CD23+ revelation that an experiment that motive allergy immune reponse because an in vitro experiment stimulates splenocytes of a NC/Nga mouse same time by PWM, and interleukin-4, eotaxin 2, CCR3, TARC mRNA outturn that bear in splenocytes decreased remarkably by Jeseupwiryeongtang-Kamibang(JWRTK) medicines. Th1 cell and Th2 cell observe to be shifted by secretion amount of IL-4 and IFN-$\gamma$ by Jeseupwiryeongtang-Kamibang(JWRTK) medicines could know that Jeseupwiryeongtang-Kamibang(JWRTK) medicines can use usefully in allergy autoimmnune diease.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.5
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• pp.2513-2518
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• 2016

Background: In 2008, non-Hodgkin lymphoma ranked tenth among other malignancies worldwide with an incidence of around 5 cases per 100,000 in both genders. The latest available rates in Tunisia are from 2006. Materials and Methods: This study aimed to provide an update about NHL incidence for 2009 and its trend between 1998 and 2009 as well as a projection until 2024, using data from the Salah Azaiz Institute hospital registry and the Noth Tunisia cancer registry. Results: In 2009, the NHL incidence in the north of Tunisia was 4.03 cases per 100,000, 4.97 for men and 3.10 for women. Diffuse large B-cell lymphoma (DLBCL) accounted for 63.2% of all NHL subtypes. Between 1998 and 2009, the overall trend showed no significant change. When we compared the trend between two periods (1998-2005 and 2005-2009), joinpoint regression showed a significant decrease of NHL incidence in the first period with an annual percentage change (APC) of -6.7% (95% CI:[-11.2%;-2%]), then the incidence significantly increased from 2005 to 2009 with an APC of 30.5% (95% CI: [16.1%; 46.6%]. The analyses of the different subtype trends showed a significant decrease in DLBCL incidence between 1998 and 2000 (APC:-21.5; 95% CI: [-31.4%;-10.2%]) then the incidence significantly increased between 2004 and 2007 (APC: 18.5; 95% CI: [3,6%;35.5%]). Joint point analysis of the age-period-cohort model projection showed a significant increase between 2002 and 2024 with an APC of 4.5% (%95 CI: [1.5%; 7.5%]). The estimated ASR for 2024 was 4.55/100 000 (95% CI: [3.37; 6.15]). Conclusions: This study revealed an overall steady trend in the incidence of NHL in northern Tunisia between 1998 and 2009. Projection showed an increase in the incidence in NHL in both genders which draw the attention to the national and worldwide burden of this malignancy.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.40 no.11
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• pp.717-726
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• 2016

This study evaluated the effect of aspect ratio of an enclosure with a heated inner circular cylinder on three-dimensional natural convection. The immersed boundary method was used to model the inner circular cylinder based on the finite volume method. The Rayleigh number was varied between $10^5$ and $10^6$, and the Prandtl number was maintained at 0.7. The aspect ratio of the three-dimensional enclosure was changed in steps of 1 within a range of 1-4 by increasing the width of the enclosure. In this study, the flow and thermal fields in the enclosure reached the steady state, and showed a mirror-symmetric pattern with respect to the center plane (x=0). In addition, the surface-averaged Nusselt number of the inner circular cylinder increased, while the total surface-averaged Nusselt number of the enclosure walls decreased with increase in the aspect ratio of the enclosure.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.39 no.3
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• pp.207-214
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• 2015

The preliminary design of a radial inflow turbine using R134a as the working fluid at 5 kW of power for application to ocean thermal energy conversion (OTEC) is performed to obtain the trends for the efficiency and geometrical dimensions of the turbine. Using input conditions that included a turbine inlet temperature of $25^{\circ}C$, an outlet static pressure of 4.9 bar, and a mass flow rate of 1.16 kg/s, the results of a mean flow analysis show the major dimensions of the turbine, along with an angular velocity of 12,820 rpm. Based on these results, a three-dimensional turbine model is constructed for a computational fluid dynamics (CFD) analysis. The flow characteristics inside the turbine, including the volute and nozzle, are investigated using the CFD software ANSYS CFX. For a pertinent number of nozzle guide vanes, ranging from 10 to 15, the turbine efficiency was higher than 80%, with the highest efficiency shown by a nozzle with 15 guide vanes.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.36 no.3
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• pp.301-307
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• 2012

The characteristics of pressure loss in an asymmetric bifurcating tube were investigated numerically for steady inspiratory conditions. The loss coefficient K calculated for various asymmetry and flow-distribution ratios found in human lung airways showed a power-law dependence on the Reynolds number (Re) and length-to-diameter ratio (L/d), with different exponents for Re $\geq$ 100 and Re < 100. The fundamental characteristics of the asymmetric bifurcation are similar to the case of symmetric bifurcation. In addition, the effect of skewed inlet velocity profiles on the pressure loss was weak, and decreased with an increasing number of bifurcations.

• The Journal of Society for e-Business Studies
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• v.9 no.3
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• pp.259-276
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• 2004

ebXML and Web Services provide UDDI and ebXML registry for storing and managing the business and Service information of companies, respectively. Recently, W3C have released the OWL(Web Ontology Language) to Recommendation, and OWL-S proposed to describe the semantics of Web Services using the OWL ontologies. In this paper, we compared the OWL-S with the registry information model(RIM) of ebXML and the data structure of UDDI, and directly connect ones, which that of ebXML similar to that of UDDI; we extend the structure of the OWL to connect the rests. Consequently, our system enables to construct the ontologies of services and discover their semantics by using the information stored in the registries, and tintegrate UDDI, ebXML registry and OWL-S registry. By using the extending OWL-S documents in our system, agents can utilize for the semantic matchmaking.

• Wind and Structures
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• v.23 no.4
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• pp.275-300
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• 2016

Synchronous multi-pressure measurements were carried out with relatively long time duration for a double-layer reticulated shell roof model in the atmospheric boundary layer wind tunnel. Since the long roof is open at two ends for the storage of coal piles, three different testing cases were considered as the empty roof without coal piles (Case A), half coal piles inside (Case B) and full coal piles inside (Case C). Based on the wind tunnel test results, non-Gaussian time-dependent statistics of net wind pressure on the shell roof were quantified in terms of skewness and kurtosis. It was found that the direct statistical estimation of high-order moments and peak factors is quite sensitive to the duration of wind pressure time-history data. The maximum value of COVs (Coefficients of variations) of high-order moments is up to 1.05 for several measured pressure processes. The Mixture distribution models are proposed for better modeling the distribution of a parent pressure process. With the aid of mixture parent distribution models, the existing translated-peak-process (TPP) method has been revised and improved in the estimation of non-Gaussian peak factors. Finally, non-Gaussian peak factors of wind pressure, particularly for those observed hardening pressure process, were calculated by employing various state-of-the-art methods and compared to the direct statistical analysis of the measured long-duration wind pressure data. The estimated non-Gaussian peak factors for a hardening pressure process at the leading edge of the roof were varying from 3.6229, 3.3693 to 3.3416 corresponding to three different cases of A, B and C.

• Bulletin of the Korean Chemical Society
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• v.35 no.12
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• pp.3495-3501
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• 2014

A novel crystal, the mono-protonated metformin acetate (1), was obtained and characterized by elemental analysis, IR spectroscopy and X-ray crystallography. It was found that one of the imino group in the metformin cation was protonated along with the proton transfer from the secondary amino group to the other imino group. Its crystal structure was then compared with the previously reported diprotonated metformin oxalate (2). The difference between them is that the mono-protonated metformin cations can be linked by hydrogen bonding to form dimers while the diprotonated metformin cations cannot. Both of them are stabilized by intermolecular hydrogen bonds to assemble a 3-D supermolecular structure. The four potential tautomer of the mono-protonated metformin cation (tautomers 1a, 1b, 1c and 1d) were optimized and their single point energies were calculated by Density Functional Theory (DFT) B3LYP method based on the Polarized Continuum Model (PCM) in water, which shows that the most likely existed tautomer in human cells is the same in the crystal structure. Based on the optimized structure, their Wiberg bond orders, Natural Population Analysis (NPA) atomic charges, molecular electrostatic potential (MEP) maps were calculated to analyze their electronic structures, which were then compared with the corresponding values of the diprotonated metformin cation (cation 2) and the neutral metformin (compound 3). Finally, the possible tautomeric mechanism of the mono-protonated metformin cation was discussed based on the observed phenomena.