• Transactions of the Korean Society of Mechanical Engineers B
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• v.41 no.11
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• pp.719-726
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• 2017

An experimental study was performed to investigate the combined effects of the pitch and heat flux of nearby tubes on boiling in a pool as well as the heat transfer from a horizontally-installed tube bundle. For this test, two smooth stainless steel tubes (19 mm outside diameter) were used, and the water was at atmospheric pressure. The pitch of these tubes was varied between 28.5 mm and 95 mm, and the heat flux of the nearby tube altered between 0 and $90kW/m^2$. Enhancements in heat transfer were clearly observed when the heat flux of the nearby tube increased while the heat flux of the test section remained below $40kW/m^2$. The tube pitch was found to have a negligible effect on heat transfer when the pitch was greater than four times larger than the tube diameter. The circulating flow, convective flow, and liquid agitation were all seen to enhance heat transfer; however, the interaction between the flow and coalescence of bubbles was detrimental to heat transfer.

• Korean journal of food and cookery science
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• v.16 no.2
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• pp.151-159
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• 2000

The effects of bromelain and $\alpha$-chymotrypsin treatments on the functional properties(foaming capacity, foaming stability, emulsifying capacity, and emulsifying stability) of soy protein isolate(SPI) and the addition of various sweeteners(sucrose, sorbitol, xylitol) on the quality attributes(viscosity, overrun ratio, melt-down property, and sensory characteristic) of soy ice cream were studied. SPI was more effectively hydrolyzed with $\alpha$-chymotrypsin than bromelain, resulting in a better foaming and emulsifying capacity. Adding xylitol could significantly improve the viscosity, overrun and melt-down property of soy ice creams while the effect was the lowest in the sucrose addition. Bromelain treatment caused a lower apparent viscosity of SPI suspension compared with $\alpha$-chymotrypsin treatment and untreated. The overrun ratios of the soy ice cream prepared with bromelain and $\alpha$-chymotrypsin treated SPI were 18.9∼25.9% and 24.9∼40.3%, respectively as a result of freezing with agitation for 20 min in an ice cream maker. Comparatively, untreated SPI could bring only 15.8∼21.4% overrun ratios after operating for 15 min. The bromelain treatment caused high melt-down tendency of the product while soy ice cream with untreated SPI showed an opposite trend. In sensory characteristics, no significant differences in the strength of beany flavor were noted among the samples. Sweetness, bitter taste, icy feel, and mouthfeel of the product were greatly affected by the enzyme-treatment of SPI. Soy ice cream added with xylitol after $\alpha$-chymotrypsin treatment was the most acceptable among all samples.

• Journal of Korean Society for Quality Management
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• v.39 no.3
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• pp.400-411
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• 2011

Process variables are factors in an experiment that are not mixture components but could affect the blending properties of the mixture ingredients. For example, the effectiveness of an etching solution which is measured as an etch rate is not only a function of the proportions of the three acids that are combined to form the mixture, but also depends on the temperature of the solution and the agitation rate. Efficient designs for the mixture components-process variables experiments depend on the mixture components-process variables model which is called a combined model. We often use the product model between the canonical polynomial model for the mixture and process variables model as a combined model. In this paper we propose three starting models for the mixture components-process variables experiments. One of the starting model we are considering is the model which includes product terms up to cubic order interactions between mixture effects and the linear & pure quadratic effect of the process variables from the product model. In this paper, we propose a method for finding robust designs and practical designs with respect to D-, G-, and I-optimality for the various starting combined models and then, we find practically efficient and robust designs for estimating the regression coefficients for those models. We find the prediction capability of those recommended designs in the case of three components and three process variables to be good by checking FDS(Fraction of Design Space) plots.

• The Korean Journal of Pain
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• v.10 no.1
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• pp.48-53
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• 1997

Background : Epidural morphine provides excellent postoperative analgesia but is often associated with side effects such as nausea, vomiting and pruritus. It has been reported that mixed agonist-antagonist, nalbuphine can reverse side effects of epidural morphine without compromising analgesia. This study was designed to compare the efficacy of each intravenous dose of nalbuphine for treatment of side effects following epidural morphine. Methods : All patients received continuous infusion(2 ml/hr) of epidural morphine-local anesthetics mixture(morphine 4 mg, 1% mepivacaine 50 ml and 0.25% bupivacaine 50 ml) following a loading dose (morphine 2 mg with 1% mepivacaine 7 ml). Patients requesting treatment for nausea, vomiting and pruritus randomly received intravenous nalbuphine 0.05 mg/kg(Group 1; n=20), 0.1 mg/kg(Group 2; n=20) or 0.15 mg/kg(Group 3; n=20). The severity of nausea, vomiting, pruritus, degree of pain, sedation and vital sign were assessed prior to and 30 min after each dose. Results : The severity of nausea, vomiting and pruritus decreased significantly in all groups(p<0.01). Pain and sedation scores were unchanged in all groups. One patient received nalbuphine 0.15 mg/kg, complained of dizziness, agitation and palpitation. His blood pressure who had increased to 170/100 after first dose. Conclusions : This study suggests that intravenous nalbuphine is good for treatment of side effects following epidural morphine, and the dose of Group 1, 0.05 mg/kg, may be recommended as an optimal dose.

• Journal of the Korean Chemical Society
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• v.54 no.3
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• pp.300-309
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• 2010

The ability of sodium-exchanged clay particles as an adsorbent for the removal of commercial dyes, Methylene blue (MB) and Malachite green oxalate (MG) from aqueous solutions has been investigated under various experimental conditions. The effect of the experimental parameters, such as pH solution, agitation time, adsorbate concentration and adsorbent dose were examined. Maximum adsorption of dyes, i.e. >90% has been achieved in aqueous solutions using 0.03 g of clay at a pH of 7 and 298 K for both dyes. The adsorption process was a fast and the equilibrium was obtained within the first 5 min. For the adsorption of both MB and MG dyes, the pseudo-second-order reaction kinetics provides the best correlation of the experimental data. The adsorption equilibrium results follow Langmuir and Dubini-Radushkevich (D-R) isotherms with high regression coefficients $R^2$ > 0.98. The mean free energies $E_a$ of adsorption from D-R model were 3.779 and 2.564 kj/mol for MB and MG respectively, which corresponds to a physisorption process.

• Korean Journal of Clinical Pharmacy
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• v.25 no.1
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• pp.56-58
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• 2015

Summary: We report the first hepatic adverse effect of tosufloxacin tosylate in a muscle invasive bladder cancer patient with normal liver functions and with scheduling to undergo a surgical operation for a neobladder. Tosufloxacin tosylate 150 mg was administered to a 57-year-old man who maintained transurethral resection of bladder tumor (TUR-BT) postoperative multiple medications. His labs presented significant increases in alanine amino transferase (ALT) and aspartate amino transferase (AST) levels with 2-week compliance of 150 mg tablet three times a day. After discontinuing tosufloxacin tosylate, the levels slowly decreased and completely returned to normal ranges without any intervention in a few weeks. The Naranjo Causality Algorithm indicates a probable relationship between increased ALT and tosufloxacin. The patient was to have the second surgical operation as scheduled after getting normal range of ATL level. Therefore, tosufloxacin should be avoided in patients at risk for having liver dysfunctions or diseases if the patients have a schedule for any operation. Background: Tosufloxacin tosylate has been shown to have favorable benefits as an antibiotic. Tosufloxacin tosylate may be considered to have the adverse effects such as nauseas, vomiting, diarrhea, abdominal pain, stomatitis, tendonitis, tendon rupture, headache, dizziness, drowsiness, insomnia, weakness, agitation including hemolysis in the event of glucose-6-phosphate dehydrogenase deficiency as other fluoroquinolones. More severe adverse reactions of tosufloxacin tosylate over the above common adverse effects of fluoroquinolones were thrombocytopenia and nephritis. It also is not well known that tosufloxacin can cause hepatic problem. Here the study reports the first hepatic reaction from tosufloxacin and might arouse heath care providers' attention to appropriate drug choice for patients.

• The KSFM Journal of Fluid Machinery
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• v.17 no.6
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• pp.29-37
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• 2014

Non-Newtonian fluid mechanics takes charge of an important role in the oil industries. Especially in the oil well drilling process, the drilling fluid such as mud keeps the drill bit cool and clean during drilling, with suspending drill cuttings and lubricating a drill bit. The purpose of this study is to examine the effect of fluid mud rheological properties to predict different characteristics of non-Newtonian fluid in the mud mixing tank on offshore drilling platforms. In this paper, ANSYS fluent package was used for the simulation to solve the hydrodynamic force and to evaluate mud mixing time. Prediction of the power consumption and the pumping effectiveness has been presented with different operating fluid models as Newtonian and non-Newtonian fluid. The comparison between Newtonain mud model and non-Newtonian mud model is confirmed by the CFD simulation method of drilling mud mixing tank. The results present useful information for the design of the drilling mud mixing tanks and provide some guidance on the use of CFD tool for such non-Newtonian fluid flow.

• Journal of Environmental Health Sciences
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• v.29 no.3
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• pp.72-78
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• 2003

In the process of producing chitosan from crustacean shell, the use of excessive acid and alkli is causing the problems of environmental pollution and of production cost. In this study, one way to solve these problems is to cultivate fungi, then, to extract chitosan from the cell wall. By means of flask incubation and batch cultivation, the optimum cultivation conditions for mass production of continuous cultivation was found. Four strains used for the production of fungal chitosan were Gongronella butleri IF08080, Absidia coerulea IF05301, Rhizopus delemar IF04775, Mucor tuberculisporus IF09256. In flask incubation to select strain of producing much chitosan by means of experiment of the effect of initial pH, Absidia coerulea IFO 5301 had highest yield in FCs, 258.1 $\pm$ 47.3 mg/200 $m\ell$l at pH 6.5. In flask incubation under the optimum cultivation condition, temperature 27$^{\circ}C$, culture time 6days, glucose 2%, peptone 1%, (NH$_4$)$_2$ SO$_4$ 0.5%, $K_2$HPO$_4$ 0.1 %, Nacl 0.1 %, MgSO$_4$ㆍ7$H_2O$ 0.05%, CaCl$_2$ㆍ2$H_2O$ 0.01 %, the yield of DCW brought the highest yields. In batch bioreactor, the optimum cultivation condition was that cell suspended solution was 70 $m\ell$, aeration rate 0.5 l/min, agitation rate 800 rpm, culture time 36 hr. In continuous bioreactor, the optimum substrate flow rate was 4 ι/day.

• Journal of the Korean Chemical Society
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• v.16 no.5
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• pp.304-313
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• 1972

This paper reports the improvements of the dialysis apparatus and operations since there are some problems to be improved in the dialysis method which is applied to determine the ionic and molecular weight of dissolved particles. The hook gauge was utilized in order to control the surface level of the dialysing solution and the solvent to be equal with the precision of 0.02 mm to minimize the osmotic and filtration effects. An accurate agitation velocity for both solutions was maintained and so was the same temperature for both solutions with ${\pm}0.01^{\circ}C$ precision. The dialysis membrane was fixed uniformly and flatly on one end of the dialysis cylinder by using a newly developed ring. The volume change of the dialysing solution during the dialysis was reduced to the range of -1.62 ~ +0.92%. Optimum duration of dialysis was searched from the relation between the osmotic and filtration effect and the pore size of the membrane.

• Mycobiology
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• v.47 no.4
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• pp.512-520
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• 2019

Statistical experimental methods were used to optimize the medium for mass production of a novel laccase3 (Lac3) by recombinant Saccharomyces cerevisiae TYEGLAC3-1. The basic medium was composed of glucose, casamino acids, yeast nitrogen base without amino acids (YNB w/o AA), tryptophan, and adenine. A one-factor-at-a-time approach followed by the fractional factorial design identified galactose, glutamic acid, and ammonium sulfate, as significant carbon, nitrogen, and mineral sources, respectively. The steepest ascent method and response surface methodology (RSM) determined that the optimal medium was (g/L): galactose, 19.16; glutamic acid, 5.0; and YNB w/o AA, 10.46. In this medium, the Lac3 activity (277.04 mU/mL) was 13.5 times higher than that of the basic medium (20.50 mU/mL). The effect of temperature, pH, agitation (rpm), and aeration (vvm) was further examined in a batch fermenter. The best Lac3 activity was 1176.04 mU/mL at 25 ℃, pH 3.5, 100 rpm, and 1 vvm in batch culture.