• Structural Engineering and Mechanics
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• v.48 no.6
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• pp.849-878
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• 2013

This paper consists of two parts, which broadly examines solution techniques abilities for the structures with geometrical nonlinear behavior. In part I of the article, formulations of several well-known approaches will be presented. These solution strategies include different groups, such as: residual load minimization, normal plane, updated normal plane, cylindrical arc length, work control, residual displacement minimization, generalized displacement control, modified normal flow, and three-parameter ellipsoidal, hyperbolic, and polynomial schemes. For better understanding and easier application of the solution techniques, a consistent mathematical notation is employed in all formulations for correction and predictor steps. Moreover, other features of these approaches and their algorithms will be investigated. Common methods of determining the amount and sign of load factor increment in the predictor step and choosing the correct root in predictor and corrector step will be reviewed. The way that these features are determined is very important for tracing of the structural equilibrium path. In the second part of article, robustness and efficiency of the solution schemes will be comprehensively evaluated by performing numerical analyses.

• Journal of Korean Society for Atmospheric Environment
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• v.8 no.1
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• pp.58-67
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• 1992

For removing $NO_x$ and $SO_x$ from the flue gases emitted from stationary sources, $V_2O_5-MoO_3/TiO_2$ catalysts were prepared by the conventional impregnation method (aqueous solution) and a sort of surface fixation method(nonaqueous solution) as reported excellent reproducibility catalysts. And these catalysts observed their catalytic activities as well as their surface properties. V-Mo-O oxide, prepared from nonaqueous solution of $VOCl_3$ and $Mo(CO)_6$ and aqeous solution method, was supported as amorphous state by XRD and SEM measurements. The infrared spectra of fresh and used catalysts showed that in used catalysts, V=O bands decreased and new bands of vanadium oxysulfate bands were very sensitive. So the catalysts prepared from nonaqueous solution may bring about the high activity. Results from catalytic activity measurements at 350$^\circ$C, in the presence of $SO_2, NO$ conversion was more increased than in absence of $SO_2$. As the $MoO_3$ was added to $V_2O_5/TiO_2 system, SO_2$ conversion increased. It found that from the results, $V_2O-5-MoO_3/TiO_2$ catalysts prepared from an nonaqueous solution may bring about the high activity for both the reaction of NO and $SO_2$ removal.

• Journal of Bio-Environment Control
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• v.1 no.1
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• pp.52-60
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• 1992

The optimum management of nutrient solution needs the effective combination of fertilizers as well as the accurate control of nutrient solution. This study was attempt to make a supporting system for effective fertilizer combination by using computer and also to develop a EC predicting equation for keeping the EC of solution within the allowable range after application of combined fertilizers. The supporting system consists of three parts : (1) data bases, (2) rules for deciding the kinds and amounts of fertilizers and (3) main control. With input data, the main control automatically constructs the network connecting the related data bases and subsequently executes the operation of searching proper fertilizers through it. For more effective searching, fertilizers are classified into two levels(level 1 and level 2) in consideration of solubility, price, and frequency in use, and searched in that order. The EC prediction equation, a extended form of the Robinson and Stroke's theoretical equation only available for a binary electrolyte, is suggested for predicting the EC of the nutrient solution containing many kinds of inorganic compounds. The comparison of predicted and measured ECs showed good agreements with the high correlation between the predicted EC decrement by ion interaction and the actual one(limiting EC minus measured EC).

• Journal of Embryo Transfer
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• v.14 no.3
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• pp.145-153
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• 1999

This study was conducted to investigate the effects of vitrification solution and developmental stage on the survival rate of vitrified-thawed human blastocyst embryos. Human blastocyst embryos were cryopreserved by vitrification using EFS and GE solution, and their survival rates were examined after thawing and further culture. EFS solution was consisted of 40% ethylene glycol, 18% Ficoll 70 and 0.3M sucrose. GE solution was consisted of 25% glycerol and 25% ethylene glycol. Embryos were exposed to EFS and GE solution by 2 steps and 3 steps, respectively, and plunged into liquid nitrogen after loading into 0.25ml plastic straws. Blastocysts were classified into 4 groups in accordance with their developmental stage: into 1) EEB, 2) MEB and 3) EdB, of blastocysts developed on day 5, and 4) 6d-Bla(the blastocysts which formed on day 6). The blastocysts at each stage were vitrified by GE solution and cryopreserved in LN2. After thawing them, we examined their survival rates, respectively. The resulted of this study were as follows: 1. The survival rate of blastocysts vitrified by GE solution was 64.4%, significantly higher than that (5.7%) vitrified by EFS solution (P<0.001). 2. When the blastocysts were vitrified by GE solution according to each developmental stage, the survival rates of EEB, MEB, EdB and 6d-Bla were 65.9%, 65.9%, 73.2% and 58.1%, respectively. In conclusion, the cryopreservation of human blastocysts by vitrification is likely to have a marked advantage in terms of cost, work and time as compared to the conventional slow freezing in IVF-ET programs.

• Journal of the Korean Ceramic Society
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• v.22 no.3
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• pp.72-76
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• 1985

Single crystals of the compound MeI $(LiMoO_4)$ and $Me^I(LiWO_4)$ ($Me^I=K$, Rb, Cs) were synthesized by slow evaporation from aqueous solution and bycooling from melt. The compounds of potassium or rubidium are hygroscopic and they form easily hydrated crystals $Me^I LiMoO_4$.$H_2O$ or $Me^ILiMoO_4$.$H_2O$ or $Me^ILiWO_4$.$H_2O$ from aqueous solution. The structures of these hydrated crystals are each other isotypic and they are built up of distorted layers of $(LiMoO_5)$ or $(LiWO_5)$. There exist two types of tetrahedral framework structures in this group of anhydrous molybdates and tung-states ; tridymite-type and cristobalite-type. $KLiMoO_4$ and $KLiWO_4$ have two types of polymorphic structures where as only the cristobalite-type is found in the Rb-and Cs-compounds. The system $KLiSO_4-KLiMoO_4$ was studied. Two components are almost immiscible but there eixst a narrow area of solid solution on the side of sulfate in the system.

• Korean Journal of Acupuncture
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• v.21 no.2
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• pp.139-145
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• 2004

Objectives : Inhibition of phase I enzymes such as cytochrome P450 (CYP) 1A1 or 1A2 is considered a major mechanism of protection against initiation of carcinogenesis. The inhibition of toxic enzymes and CYP were studied with so many oriental herbral medicine. Recently, numerous polysaccharides and polysaccharide-protein complexes have been isolated from mushrooms and used as a source of therapeutic agents. The most promising biopharmacological activities of these polymers are their immunomodulation and anti cancer. But, in this study the inhibitory effect was on the aqua-acupuncture of Lentinus edodes. Materials : Lentinus edodes aqua-acupuncture solution (LEAS) was prepared and tested for the inhibition of cytochrome P450 (CYP) 1A1 and 1A2 activities. LEAS type I from fruit body of these mushrooms. Type II was extracted from cultured broth of Lentinus edodes mycelum. Results : LEAS type I and type II were significantly inhibited CYP 1A1 and 1A2 enzymes at concentration of 5.0 and 10.0 mg/ml. Conclusion : These results suggested that LEAS may act as block agent against carcinogenesis by inhibition of phase I enzymes.

• Nuclear Engineering and Technology
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• v.4 no.3
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• pp.186-193
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• 1972

For efficient micro scale syntheses of Rose $Bengal-^{131}I$, $Hippuran-^{131}I$, and $H.S.A.-^{131}I$, the dependence of labelling yields on pH, on salt contents, and on the volume of buffer solution in the reaction mixtures as well as the reaction apparatus were studied. pH of 5.6 was optimum for preparation of both Rose $Bengal-_{131}I$ and Hippuran $-^{13}I$ but pH of 8.5 was optimum for preparation of $H.S.A.-^{131}I$. Salt in the reaction mixtures hindered drastically the formation of $Hippuran-^{131}I$ but it slightly increased the labelling yield of H.S.A.. The compactly closed reaction vessels were effective for preparations of both Rose $Bengal-^{131}I$and $Hippuran-^{131}I$ in small volume. Thereupon, the labelling procedures were modified to bring about higher labelling yields and better reproducibilities. By these newly established procedures, the labelling yields of Rose $Bengal-^{131}I$ and $Hippuran-^{131}I$ could be increased even with the home-produced sodium $iodide-^{131}I$ solution containing reducing agent.

• Korean Journal of Mathematics
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• v.22 no.1
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• pp.123-131
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• 2014

The purpose of this paper is to study the perturbation analysis of the matrix equation $X=I-A^*X^{-1}A+B^*X^{-1}B$. Based on the matrix differentiation, we give a precise perturbation bound for the positive definite solution. A numerical example is presented to illustrate the shrpness of the perturbation bound.

• Proceedings of the IEEK Conference
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• 2001.06b
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• pp.33-36
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• 2001

In this paper, we have studied the characteristics of wet etching using citric acid based wet etchant. We have used the citric acid / hydrogen peroxide solution, citric acid / hydrogen peroxide / D.I. water solution. From our experimental result, a volumetric 1：3 ratio of citric acid and hydrogen peroxide and 1 ： 3 ： 1 ratio of citric acid, hydrogen peroxide, and D.I. water is shown to be a better wet etchant of PHEMT's system.

• Textile Coloration and Finishing
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• v.3 no.4
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• pp.17-21
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• 1991

A rigid polymer, cellulose triacetate (CTA) dissolved in a combination of trifluoroacetic acid (TFA) and methylene chloride (MC) solution are liguid crystalline above a certain concentration. A flexible polymer, polyethylene terephthalate (PET) also dissolves in TFA/MC, but does not form liguid crystal phase. Ternary solutions, CTA/PET/TFA-MC which CTA and PET were mixed in a same solvent TFA/MC (6/4 : v/v) showed phase separation and mesophase formation.