• Korean Chemical Engineering Research
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• v.44 no.3
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• pp.277-283
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• 2006

Aqueous solution of sodium glycinate was checked as a suitable $CO_2$ absorbent from the flu gas in the thermal power plant. For this purpose, solubility, vapor pressure, latent heat of vaporization and thermal conductivity were determined for pure and aqueous solution of sodium glycinate. The solubility of sodium glycinate in the solvent, 25 g of $H_2O$, was increased with increasing the temperature and their relation was represented as a first order equation of y = 0.3471x + 20.993. The vapor pressure for 10 wt％ to 60 wt％ of aqueous sodium glycinate solution were determined and the latent heat of vaporization of each aqueous solution was calculated from measured vapor pressure using Clausius-Clapeyron equation. Besides, thermal conductivity of sodium glycinate powder was also determined and it was $1.0933kcal/m{\cdot}hr{\cdot}^{\circ}C$.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.5
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• pp.42-50
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• 2021

The purpose of this study was to identify and analyze the communication behavior styles of hemodialysis nurses based on the structured Q-methodology. The Q-population was formulated based on literature reviews and in-depth interviews with 10 hemodialysis nurses who were working in hospitals in Seoul and Anyang-si, Gyeonggi Province. A total of 50 Q-samples, which were believed to best represent the communication behavior styles of hemodialysis nurses, were selected from the Q-population by the author and a professor majoring in nursing. 30 P-samples were selected from hemodialysis nurses who were working in primary, secondary, and tertiary hospitals in Seoul. Q-sorting was performed by P-samples and data was analyzed through the pc-QUANL program. The results suggested that there are four types of communication behavior styles of hemodialysis nurses, namely: "type I: listening and speaking courteously with an active mind", "type II: listening and speaking courteously with a receptive mind", "type III: advising with an explanation" and "type IV: super-reasonable with a defensive mind". It is expected that the analytical results described here may provide basic information that can be used to develop educational material for hemodialysis nurses.

• Polymer(Korea)
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• v.28 no.5
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• pp.374-381
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• 2004

Gas permeability of low density polyethylene (LDPE) film containing zeolite powder for $CO_2,\;O_2$ and $N_2$ were investigated. Zeolite powders modified by cations or surfactant were compounded with LDPE to produce $20 wt\%$ masterbatch. After blending the masterbatch with LDPE, zeolite filled films were prepared by the blown film process. Finally, the composite films containing zeolite loadings of 0, 3,5, and $10 wt\%$ were produced. A gas permeability apparatus based on the variable volume principle was designed to analyze the characteristics of films. Experiments showed a general trend that gas permeabilities first decreased and then increased as the zeolite content was increased. Surfactant modified zeolite showed a better interfacial adhesion with the matrix, but the film did not show a discernible difference in gas permeability compared with the other modified films. The difference of temperature dependences in the gas permeabilities of composite films was slightly smaller than that of LDPE film.

• The Korean Journal of Food And Nutrition
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• v.27 no.4
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• pp.699-705
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• 2014

This study was conducted to select the coagulant for konjac processing and to identify the antibacterial activity on foodborn pathogens by concentration of $Ca(OH)_2$. In rheological properties such as hardness, gumminess and chewiness, konjac jelly were increased by progressing coagulation regardless of coagulant. In mineral contents, the Ca content of konjac jelly made with $Ca(OH)_2$ was significantly higher than that of NaOH. On the contrary, the Na content of konjac jelly made with NaOH coagulant was significantly higher than that of $Ca(OH)_2$. There were no significant differences in the Mg and P contents according to coagulant. In sensory evaluation, there were no significant differences in the color, flavor, taste, texture and overall quality according to coagulant. The antimicrobial activities of Staphylococcus aureus, E. coli, Salmonella typhimurium were inhibited in proportion to the concentration of $Ca(OH)_2$. According to the manufacturing process of konjac jelly, the change in microorganism was not found after molding.

• Journal of Korean Society of Steel Construction
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• v.25 no.1
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• pp.35-45
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• 2013

The concrete-filled tube column has the excellent structural performance. But it is difficult to connect with column and beam because of closed section. It suggests that pipe should be produced by welding two sides together where two shapes are joined after a channel is pre-welded onto the three sides in order to form an internal diaphragm. The upper diaphragm of the connection used the horizontal plate and the lower diaphragm used the Vertical plate. This research performed 6 monotonic tension experiments describing the connection upside and downside in order to evaluate the structural capability of the offered connection. And the cyclic loading experiment was performed about 2 T-Type column to beam connections. As to the experimental result edge cutting geometry, there was no big effect. An increase in the number of holes of the plate ultimate strength was increased by 5% and The thickness of the plate increases, the maximum strength was increased by 4%. T-Type connections until it reaches the plastic moment showed a stable behavior.

• Journal of the Korean Society for Nondestructive Testing
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• v.17 no.2
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• pp.89-99
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• 1997

Although discontinuously reinforced metal matrix composite(MMC) is one of the most promising materials for applications of aerospace, automotive industries, the thermal residual stresses developed in the MMC due to the mismatch in coefficients of thermal expansion between the matrix and the fiber under a temperature change has been pointed out as one of the serious problem in practical applications. There are very limited nondestructive techniques to measure the residual stress of composite materials. However, many difficulties have been reported in their applications. Therefore it is important to establish analytical model to evaluate the thermal residual stress of MMC for practical engineering application. In this study, an elastic model is developed to predict the average thermal residual stresses in the matrix and fiber of a misoriented short fiber composite. The thermal residual stresses are induced by the mismatch in the coefficient of the thermal expansion of the matrix and fiber when the composite is subjected to a uniform temperature change. The model considers two-dimensional in-plane fiber misorientation. The analytical formulation of the model is based on Eshelby's equivalent inclusion method and is unique in that it is able to account for interactions among fibers. This model is more general than past models to investigate the effect of parameters which might influence thermal residual stress in composites. The present model is to investigate the effects of fiber volume fraction, distribution type, distribution cut-off angle, and aspect ratio on thermal residual stress for in-plane fiber misorientation. Fiber volume fraction, aspect ratio, and distribution cut-off angle are shown to have more significant effects on the magnitude of the thermal residual stresses than fiber distribution type for in-plane misorientation.

• Journal of Korean Ophthalmic Optics Society
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• v.6 no.1
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• pp.133-137
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• 2001

The method to make glass is tried first thing in domestic study for glasses lens. Tg of glass KzFSl was measured by DSC experiment and press method of glass of meniscus shape was studied for minimize the cost. Tg was increased $483^{\circ}C$ to $501^{\circ}C$ with increasing heating rate $2^{\circ}C/min$ to $20^{\circ}C/min$. It shows Arrhenius temperature dependence and the activation energy of Tg is ${\Delta}E$=409 kJ/mole(4.25eV) by using Ozawa method and Tg is near $480^{\circ}C$. The melt of KzFSl powder was poured to concave cast stainless and pressed convex cast stainless. The quenched glass was slow cooled with cooling rate $0.25^{\circ}C/min$ in temperature range $520{\sim}430^{\circ}C$. The glass was made without strain. It has meniscus shape and same size to commercial glasses lens.

• Journal of Korean Society of Forest Science
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• v.101 no.1
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• pp.91-95
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• 2012

To examine the sex morph, heterodichogamy, fruiting characteristics and seed viabilities of Acer palmatum, sixty three planted trees were monitered in Wonju-si for two years in terms of their sex morph, flowering and fruiting habit. Most flowers of A. palmatum are pollinated by Apis mellifera, Helophilus virgatus, a few (3.57%) are pollinated by wind. Twenty four trees (42.9%) in 2010, and twenty trees (31.7%) in 2011 were proved protandrous (PA: pollen is shed before stigmas are receptive), thirty two (50.8%) in 2010, thirty trees (47.6%) in 2011 were proved protogynous (PG: stigmas are receptive before pollen is shed). This result means that Acer palmatum has heterodichogamous sexual system. Five trees (7.9%) have changed their sex morphs; 4 trees change the sex morp PA to PG, and one does the sex morph PG to PA. Rates of sound seeds and decayed seeds were significantly different between sex morphs. Rates of sound seeds were 51.6% (2010) and 64.0% (2011) in PA, but 30.4% (2010) and 40.4% (2011) in PG. and rates of decayed seeds did 40.0% (2010) and 31.2% (2011) in PA, but 65.6% (2010) and 56.8% (2011) in PG. The differences of decayed seeds' rates between sex morphs might be related with the timing of insect pests' outbreak.

• Journal of Chest Surgery
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• v.37 no.9
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• pp.755-761
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• 2004

We evaluated the efficacy of Dor procedure in patients with ischemic left ventricular dysfunction. Material and Method: Between April 1998 and December 2002, 45 patients underwent the Dor procedure con-comitant with coronary artery bypass grafting (CABG). Left ventricular ejection fraction (LVEF) and left ventricular end-diastolic/end-systolic volumes (LVEDV/LVESV) were measured by echocardiography, myocardial SPECT, and cardiac catheterization and angiography performed at the sequence of preoperative, early postoperative, and one year postoperative stage. Result: Cardiopulmonary bypass and aortic clamp times were mean 141$\pm$64, 69$\pm$24 minutes, respectively. Intraaortic balloon pump (IABP) therapy was required in 19 patients (42%; 7 preoperatively, 9 intraoperatively, 3 postoperatively). Operative mortality rate was 2.2% (1/45). Postoperative morbidities were low cardiac output syndrome (12), atrial fibrillation (5), acute renal failure (4), and postoperative bleeding (4). Functional class (NYHA) was improved from classes 2.8 to 1.1 (p < 0,01). When we compared between the preoperative and early postoperative values, LVEF was improved from 32$\pm$9% to 52$\pm$11% (p<0.01). The asynergy portion decreased from 57$\pm$12% to 22$\pm$9%, and LVEDV/LVESV indexes improved from 125$\pm$39 mL/$m^2$, 85$\pm$30 mL/$m^2$ to 66$\pm$23 mL/$m^2$, 32$\pm$16 mL/$m^2$ (p<0.01). Although these changes in volumes were relatively preserved at postoperative one year, the left ventricular volumes showed a tendency to increase. Conclusion: After the Dor procedure for ischemic left ventricular dysfunction, LVEF improvement and left ventricular volume reduction were maintained till postoperative one year. The tendency for left ventricular volume to increase at postoperative one year suggested the requirement of strict medical management.

• Journal of the Korean Chemical Society
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• v.20 no.4
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• pp.280-289
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• 1976

The silver selenide electrode has been prepared and its properties as an indicating electrode for silver ion have been investigated. Epoxy resin was used as a filler of silver selenide electrode. Silver metal plate was directly connected with the membrane of the electrode and the silver paste was used as its binder. The sintered electrode was more sensitive and stable than the pressed electrode, and the silver selenide electrode more sensitive than the silver sulfide electrode to silver ion. The linear relationship between the electrode potential and logarithmic concentration of silver ion has been observed down to 10-6 M for the electrode. Several heavy metal ions except mercuric ion did not interfere this linearity, but halide, cyanide, and thiocyanate ions did intensively interfere owing to the formation of silver compounds and complexes. This electrode has been applied to the potentiometric titration for determining halide ion. It is concluded that interferences from ,$CN^-, SCN^-, S^-, I^-, Br^-, Cl^- and Hg^{2+}$ ions are detrimental to the practical use of the electrodes for measuring pAg.