• Journal of the Korean Data and Information Science Society
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• v.23 no.2
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• pp.385-392
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• 2012

Logistic regression is a well known binary classification method in the field of statistical learning. Mixed-effect regression models are widely used for the analysis of correlated data such as those found in longitudinal studies. We consider kernel extensions with semiparametric fixed effects and parametric random effects for the logistic regression. The estimation is performed through the penalized likelihood method based on kernel trick, and our focus is on the efficient computation and the effective hyperparameter selection. For the selection of optimal hyperparameters, cross-validation techniques are employed. Numerical results are then presented to indicate the performance of the proposed procedure.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.5
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• pp.1304-1312
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• 1993

The buoyancy effects on mixed convection heat transfer over a flat plate surface with unheated starting length is reported. The governing equations are solved by a finite difference method using Patankar scheme and the solution was numerically obtained for various mixed convection parametr $Gr_{x}/Re_{x}^3$, and Prandtl number of 0.7 Local heat flux was measured by using Schilieren Interferometer. The local heat transfer results show that the presence of the unheated starting length can significantly accentuate the effects of buoyancy. The degree of accentuation of the buoyancy effects is strongly influenced by the magnitude of $Gr_{x}/Re_{x}^3$. When the parameter is larger than the order of $10^{-3}$, the contribution of natural convection to the heat transfer coefficients increased significantly due to the unheated starting length. In contrast, when $Gr_{x}/Re_{x}^3$ is smaller then about $10^{-5}$ , the buoyancy contribution is essentially unaffected by the unheated starting length. The shape of the velocity profile is also found to be highly responsive to the interaction between the buoyancy and the starting length.

• Journal of Forest and Environmental Science
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• v.30 no.2
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• pp.179-188
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• 2014

This research reports the effects of shifting cultivation on soil environment collecting samples from 0-5 cm soil depth from five locations viz. at Burburichhara, Maichchari, Longadu, Sukurchhari and Muralipara in Rangamati district of Chittagong Hill Tracts (CHTs). Soil analyses showed that fungal and bacterial population, microbial respiration and active microbial biomass, maximum water holding capacity, conductivity and moisture contents were significantly (at least $p{\leq}0.05$) lower in shifting cultivated soil compared to adjacent mixed tree plantations at all the sites. On an average in soils of 5 different shifting cultivated lands fungal population was $1.33{\times}10^5$ CFU/g dry soil and bacterial population $1.80{\times}10^7$ CFU/g dry soil and in mixed plantations fungal population was $1.70{\times}10^5$ and bacterial population $2.51{\times}10^7$ CFU/g dry soil. Organic matter and exchangeable Ca and Mg contents were significantly (at least $p{\leq}0.05$) lower and bulk density significantly (at least $p{\leq}0.05$) higher in shifting cultivated land in most of the locations compared to adjacent mixed tree plantations. Ratios of microbial respiration and organic carbon as well as active microbial biomass and organic carbon were distinctly lower and pH higher at 3 locations in shifting cultivated soils compared to mixed plantations. Findings of various soil properties, therefore, suggest that shifting cultivation has deteriorating effects on soil environment.

• Korean Journal of Medicinal Crop Science
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• v.18 no.1
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• pp.15-21
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• 2010

This study was conducted to investigate the effects of Lycii fructus and Astragalus membranaceus mixed extracts on immunomodulators and prevention in a streptozotocin-induced diabetes rat model. A total of 28 male rats were divided into four dietary groups and fed a commercial diet (A), commercial diet plus induced diabetes by a streptozotocin (STZ) injection (B), induced diabetes by STZ plus medicinal crop extracts(I&$H^{(R)}$) diet (C), and medicinal crop extracts (I&$H^{(R)}$) diet (D). Immunoblotting analyses revealed cytokine expression, and ELISA analyses revealed immunoglobulin E and nitric oxide production. As a results, the tumor necrosis factor-$\alpha$ (TNF-$\alpha$) and inducible nitric oxide synthase (iNOS) as a inflammatory cytokine were decreased. Interleukin-6 (IL-6) and signal transducer and activation of transcription 3 (STAT3) cytokine related in diabetes expression through JAK/STAT3 pathway were also decreased. Furthermore, immunoglobulin E and nitric oxide production were decreased in the serum and lens, respectively. These results suggest that Lycii fructus and Astragalus membranaceus mixed extracts provide positive effects on immunomodulators and prevention in diabetes and eye disease complications.

• Restorative Dentistry and Endodontics
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• v.25 no.1
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• pp.63-70
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• 2000

The properties of ideal retrograde filling materials include the ability to seal the root canal system in three dimensions and well tolerated by periradicular tissues. Biocompatibility testing has been done mainly with cytotoxicity tests using cell culture. Little attention has been paid to the potential adverse influence on the inflammatory and immune reaction in the periapical tissue. The purpose of this study was to investigate the effects of retrograde filling materials on human mononuclear cells in vitro. Freshly mixed and set specimens from six materials (Z100, Tetric Ceram, Fuji II, Fuji II LC, F2000, Compoglass Flow, and ZOE) were eluated with cell culture medium for 24 hours. Cytotoxic effects of these extracts were evaluated by determining cell viability and enzyme activity using MTT and lactate dehydrogenase (LD). The production of inflammatoy bone resorptive cytokine, TNF-${\alpha}$ was measured from human peripheral blood mononuclear cells (PBMC) exposed to the extracts by means of Endogen Human TNF-${\alpha}$ ELISA kit (Wobrun, MA, U.S.A.). Eluates and diluted (1 : 10) eluates with cell culture medium from freshly mixed Fuji IT had cytotoxic effects on mononuclear cells using MTT and LD. However, eluates from set Fuji II were not cytotoxic. Eluates form set ZOE exhibited cytotoxicity with LD test. TNF-${\alpha}$ levels were high in eluates from freshly mixed Fuji II and Z100. Diluted eluates from freshly mixed Z100 and F2000 stimulated the production of TNF-${\alpha}$. However, there were no significant difference in TNF-${\alpha}$ levels compared to controls. These results indicate that some materials could possibly stimulate bone resorption in the periapical tissue by means of the production of bone resorptive cytokine.

• Journal of Environmental Science International
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• v.23 no.6
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• pp.1151-1156
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• 2014

The photocatalytic decomposition characteristics of single n-pentane, n-pentane mixed with methyl ethyl ketone (MEK), and n-pentane mixed with ethyl acetate (EA) by cylindrical UV reactor installed with $TiO_2$-coated perforated plane were studied. The effects of the residence time, the inlet gas concentration, and the oxygen concentration were investigated. The removal efficiency of n-pentane was increased with increasing the residence time and the oxygen concentration, but decreased with increasing the inlet concentration of n-pentane. The photocatalytic decomposition rates of single n-pentane, n-pentane mixed with MEK, and n-pentane mixed with EA fitted well on Langmuir-Hinshelwood kinetics equation. The maximum elimination capacities of single n-pentane, n-pentane mixed with MEK, and n-pentane mixed with EA were obtained to be $465g/m^3{\cdot}day$, $217g/m^3{\cdot}day$, and $320g/m^3{\cdot}day$, respectively. The presence of coexisting MEK and EA vapor had a negative effect on the photocatalytic decomposition of n-pentane and the negative effect of MEK was higher than that of EA.

• Journal of the Korean Society of Clothing and Textiles
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• v.25 no.5
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• pp.991-1001
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• 2001

This study has examined effects of protease on the removal of hemoglobin and triolein mixed soil with changes of soil content and soil composition from cotton and PET filament fabrics. The results obtained were as follows: The results obtained were as follows: 1) The detergency of PET fabrics was higher than that of cotton fabrics. The removal of hemoglobin was much higher than that of triolein from cotton fabrics, while the removal of hemoglobin was similar to that of triolein from PET fabrics. 2) The removal efficiency of hemoglobin and triolein was improved by protease from cotton and PET fabrics. Especially the removal efficiency of those was remarkably improved from cotton fabrics which the removal of soil was lower than PET fabrics. And the removal of hemoglobin and triolein by adding protease was increased with increase of hemoglobin content of mixed soil from cotton fabrics. 3) With the increase of hemoglobin content of mixed soil, the removal of hemoglobin was drastically increased but the removal of triolein was slightly decreased from cotton and PET fabrics. With the increase of triolein content of mixed soil, the removal of hemoglobin and triolein was decreased from cotton fabrics, but those were generally increased from PET fabrics.

• Journal of Animal Environmental Science
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• v.5 no.1
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• pp.63-72
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• 1999

This study was carried out to improve utilization of fly ash. Each animal waste was mixed with fly ash and composted This compost used at forage crops with corn, rye and alfalfa to examine to examine the fertilized efficiency and investigated productivity of forage crops, composition of this copmost and effect of fly ash on soil characteristics and composition. Content of organic matte, P2O5, K2O, CaO, MgO, Mn and B at the soil, which is given fly ash, increased. After the test crops were harvested, pH of the soil was maintained about 7 and contents of organic matter, phosphoric aicd, K, Mg, and B was increased at the soil of used fly ash. As fly ash was mixed, each DM yield of corn and rye was increased 10∼13% and 14∼21% especially alfalfa was increased 35% at the soil which is mixed fly ash with cage layer manure. As fly ash was mixed, each Crude protein (CP) of corn and rye was increased 6∼17% and about 29%, especially, as fly and cage layer manure was mixed CP of alfalfa was increased 33%. In conclusion, as fly ash is mixed with anlmal waste and use at forage crops, It makes the soil good and improve the productivity of forage crops.

• Bulletin of the Korean Chemical Society
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• v.10 no.5
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• pp.437-442
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• 1989

The cmc's of sodium dodecyl sulfate (SDS)/Triton X-100 surfactant mixtures were determined by surface tension measurement at various surfactant compositions. The cmc values were lower than those predicted from ideal mixture. The regular solution theory was applied to calculate the interaction parameter, micellar composition, and the activity coefficients of surfactants in the mixed micelle. The interaction parameter (${\beta}$) was - 2.1. The nonideality arised largely from decreased activity of SDS in the mixed micelle. The mean aggregation numbers (${\bar{n}}$) and micropolarity of hydrocarbon region of the mixed micelles were determined by luminescence probe techniques. The total aggregation number (${\bar{n}}_{SDS}+{\bar{n}}_{TX}$) in mixed micelles showed little dependency on the composition of the micelle. The apparent dielectric constant of the hydrocarbon region of the micelle vs micellar composition plot showed positive deviation from linearity. Emission and emission quenching of excited tris(2,2'-bipyridine)ruthenium(Ⅱ) cation, $(Ru(bpy)_3^{2+})$, by methylviologen ($MV^{2+}$) were also investigated in the mixed micellar solutions. The quenching rate was lowest when the mole fraction of SDS in the surfactant mixtures (${\alpha}_{SDS}$) is about 0.25 and highest at ${\alpha}_{SDS}$ = 0.85. This was explained in terms of combined effects of binding of the cations with the micelle and mobility of the bound cations on the surface of the micelles.

• Journal of Industrial and Engineering Chemistry
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• v.67
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• pp.156-163
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• 2018

High-performance mixed-matrix membranes that comprise both zeolitic imidazolate framework-8 (ZIF-8) and graphene oxide (GO) were synthesized with a solution casting technique to realize excellent $CO_2/CH_4$ separation. The incorporation of ZIF-8 nanocrystals alone in ODPA-TMPDA polyimide can be used to significantly enhance $CO_2$ permeability compared with that of pure ODPA-TMPDA. Meanwhile, the addition of a GO nanostack alone in ODPA-TMPDA contributes to improved $CO_2/CH_4$ selectivity. Hence, a composite membrane that contains both fillers displays significant enhancements in $CO_2$ permeability (up to 60%) and $CO_2/CH_4$ selectivity (up to 28%) compared with those of pure polymeric membrane. Furthermore, in contrast to the ZIF-8 mixed-matrix membrane, which showed decreased mechanical stability, it was found that the incorporation of GO could improve the mechanical strength of mixed-matrix membranes. Overall, the synergistic effects of the use of both fillers together are successfully demonstrated in this paper. Such significant improvements in the mixed-matrix membrane's $CO_2/CH_4$ separation performance and mechanical strength suggest a feasible and effective approach for potential biogas upgrading and natural gas purification.