• The Journal of Natural Sciences
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• v.8 no.1
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• pp.47-51
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• 1995

Several intermediate glasses are investigated to bond the alumina and the hydroxyapatite (HAp). The chemical compositions of the intermediate glasses are chosen as $CaO-Al_2O_3$. The mole ratio of CaO/$Al_2O_3$ is changed from 0.5 to 3.0. The lowest melting is observed at $1355^{\circ}C$ in the specimen of CaO/$Al_2O_3$ at the mole ratio of 2. With increasing contents of $Al_2O_3$, the melting temperatures gradually increase and a number of pores are observed. The sectional microstructure shows that the good wetability is observed in higher contents of CaO specimens. This implies that the good wetability is obtained in the mole ratio range of CaO/$Al_2O_3geq2$. The phase transformations are observed after treatment but the major peaks of HAp still exist.

• Information Systems Review
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• v.13 no.2
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• pp.17-41
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• 2011

A review of the related literature indicates that consumers' risk perceptions are largely affected by product involvement. This study investigates the impact of product involvement on required trust level and the online merchant choice. We developed a conceptual model that depicts the nomological relationships among product involvement, required trust level, and the online merchant choice, and formulated three hypotheses based on the conceptual model. An empirical study designed to accomplish the research objectives has been conducted using a questionnaire survey with 230 students in a university in Korea. The findings indicated that high-involvement products have higher trust level as required by consumers than low-involvement products, that consumers buying high-involvement products prefer digital storefronts, and that consumers buying low-involvement products prefer B2C e-marketplaces. The paper offers implications for academics as well as practitioners, based on the research results.

• Journal of the Korea Safety Management & Science
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• v.8 no.5
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• pp.193-209
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• 2006

Multiple regression is used to examine the relationship between a set of two or more independent variables and one dependent variable. It provides the information necessary to make predictions of the dependent variables based on several independent variables. To do so, the multiple regression equation is extended to: y=$a+{\beta}_1x_1+{\beta}_2x_2+{\ldots}+{\beta}_kx_k$ y=attractiveness a=the value of the intercept ${\beta}_1$=the slope(weighting) of the first variable ${\beta}_1$= the slope(weighting) of the second variable ${\beta}_k$=the slope of the $\kappa$th variable The resulting regression equation of this research is y=$a+{\beta}_1site's\;system+{\beta}_2customer\;satisfaction+{\beta}_3products+{\beta}_4delivery$ y=3.233+0.374(site's system)+0.268(customer satisfaction)+0.17(products)+0.077(delivery)

• Korean Chemical Engineering Research
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• v.53 no.3
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• pp.269-275
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• 2015

The adsorption characteristics of ions were evaluated for the nitrate-selective carbon electrode (NSCE) in accordance with power supply methods. The NSCE was fabricated by coating the surface of a carbon electrode with anion-exchange resin powders with high selectivity for the nitrate ion. Capacitive deionization (CDI) experiments were performed on a mixed solution of nitrate and chloride ion in constant voltage (CV) and constant current (CC) modes. The number of total adsorbed ions in CV mode was 15% greater than that in CC mode. The mole fraction of adsorbed nitrate ion showed the maximum 58%, though the mole fraction was 26% in the mixed solution. This indicates that the fabricated NSCE is highly effective for the selective adsorption of nitrate ions. The mole fraction of adsorbed nitrate was nearly constant value of 55-58% during the adsorption period in CC mode. In the case of CV mode, however, the values increased from the initial 30% to 58% at the end of adsorption. We confirmed that the current supplied to cell is important factor to determine the selective removal of nitrate.

• 한국벤처창업학회:학술대회논문집
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• 2019.11a
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• pp.113-122
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• 2019

본 연구에서는 사람중심 조직문화 특성이 중소기업의 비지니스 생태계와 회사탁월성에 어떠한 영향을 미치는지, 비지니스 생태계와 회사탁월성은 기업성과에 어떤 영향을 주는지를 연구하는데 목적이 있다. 따라서 본 연구는 기업의 사람중심 조직문화 특성을 공감, 역량개발, 권한위임, 업무몰입도로 구분하고 각각의 독립변수들이 매개 변수인 비즈니스 생태계와 화사탁월성에 미치는 영향과 비니니스 생태계와 회사탁월성이 경영성과에 미치는 영향을 살펴보는 인과관계 분석이 주된 연구대상이다. 연구의 결과를 자세히 제시하면 다음과 같다. 사람중심 조직문화 특성과 비즈니스 생태계 간의 인과관계에 대한 실증 연구결과를 요약하면 공감, 역량개발, 권한위임, 업무몰입도는 비즈니스 생태계에 유의한 영향을 미치는 것으로 나타났다. 사람중심 조직문화 특성과 회사탁월성 간의 인과관계에 대한 실증 연구결과를 요약하면 업무몰입도는 회사탁월성에 유의한 영향을 미치는 것으로 나타났으며, 공감, 역량개발, 권한위임은 통계적으로 회사탁월성에 유의한 영향을 미치지 않는 것으로 나타났다. 기업역량인 비즈니스 생태계와 회사탁월성과 경영성과 간의 인과관계에 대한 실증 연구결과를 요약하면, 비즈니스 생태계는 경영성과에 통계적으로 유의한 영향을 미치지 않는 것으로 나타났으며, 회사탁월성는 경영성과에 유의한 영향을 미치는 것으로 나타났다. 이상의 연구결과와 함께 본 연구를 통해 다음과 같은 두 가지 시사점을 제시할 수 있다. 첫째, 기존연구와 사람중심 조직문화 특성을 활용하여 중소기업을 대상으로 실증연구 했다는 점에서 본 연구의 학문적 기여점을 찾을 수 있다. 중소기업은 대기업이나 공공기관에 비해 사람중심 경영에 대한 인식이 낮을 것으로 추측되었으나 분석결과 사람중심 조직문화 특성이 기업역량과 기업성과에 중요한 영향을 미치고 있음을 확인하였다는데 큰 의미가 있다고 하겠다. 둘째, 기업은 기존의 사업중심의 전통적 기업가정신과 사람중심경영이 잘 융합되어 중소기업 핵심역량에 영향을 주고 이는 다시 기업성과로 이어지는 결과를 낳는 선순환 모형이 된다는 점에서 의미가 있다.

• Journal of Energy Engineering
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• v.19 no.2
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• pp.121-127
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• 2010

In present work, sulfonated poly(arylene biphenyklsulfone ether) copolymers containing hydroquinone moiety were successfully synthesized using 4,4'-bis[(4-chlorophenyl)sulfonyl]-1,1'-biphenyl(BCPSBP), hydroquinone sulfonic acid potassium salt(sHQ), 4,4'-sulfonyldiphenol and evaluated their characteristics. Three kinds of polymer electrolyte membranes, PBPSEH-HQ00, PBPSEH-HQ10 and PBPSEH-HQ30 were prepared by using mole fraction of sulfonated hydroquinone(sHQ). The structure of the fabricated polymers was analyzed using NMR, IR and GPC. The Mw(weight-average molecular weights) of the polymers were in the range of 62,000-213,000 g $mol^{-1}$, and the molecular weight distribution (Mw/Mn) varied from 1.66-4.04. The thermal analysis of the copolymers was carried out by TGA and DSC. The temperature of Td5% and Td10% was decreased with the mole fraction of sHQ but Tg was increased with the mole fraction. The water uptake, IEC and ion conductivity were increased with increasing the ionic cluster of the polymers. The proton conductivity equal to 9.4 mS $cm^{-1}$ was measured for the PBPSEH-HQ30 membrane at $90^{\circ}C$ and 100% relative humidity. From the observed results it is clear that the prepared hydrocarbon membrane can be considered as suitable polymer electrolyte membrane for the application of PEMFC.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.7 no.4
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• pp.77-86
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• 2012

The purpose of this paper is to review the relationship between organizational commitment, and voluntary turnover(intention to leave), and the moderating effects of personal factors(gender and occupation) on the relationship between organizational commitment and intention to leave. In order to verify and achieve the purposes mentioned above, questionnaire data are gathered and analysed from 458 employees in Daedeok Innopolis Venture Enterprises, Dae-jeon Metropolis, South Korea. Multiple regression and multiple hierarchical regression analysis are applied to test the proposed hypotheses: 1) the relationship between organizational commitment(affective commitment, continuance commitment and normative commitment) and intention to leave, 2) the moderating effects of personal factors(gender and occupation) on the relationship between organizational commitment and intention to leave. Empirical survey's findings are as follows; First, affective commitment(AC) and continuance commitment(CC) are related negatively with intention to leave(IL), but normative commitment(NC) is not related significantly with IL. Second, gender positively moderates the relationship between affective commitment and intention to leave, and occupation negatively moderates the relationship between continuance commitment and intention to leave.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.9 no.2
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• pp.81-86
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• 2011

Polymer-modified cement is the composite material made by partially replacing and strengthening the cement hydrate binders of conventional mortar with polymeric modifiers such as polymer latexes and redispersible polymeric modifiers. It is known that the addition of polymer to cement mortar leads to improved quality, which would be expected to have a high chemical resistance. Therefore, the purpose of this study is to identify the improved chemical resistance, such as low permeability and low ion diffusivity, of the polymer-modified cement as a solidification agent for the radwaste. First, polymer-modified cement specimens by latex modification were prepared according to the polymer content from 0% to 30% to select the optimized polymer content. At those specimens, the water-to-cement (W/C) ratio was maintained to 33% and 50% respectively. After the much curing time, the structural integrity of specimens was evaluated through the compressive strength test and the porosity evaluation by the water immersion method. From the results, 10% of the polymer content at 33% of the W/C ratio was shown to have the most improved quality. Finally, the leaching test referredfrom ANS 16.1 for the specimens having the most improved quality was conducted. Dedicated specimens for the leaching test were then mixed with radioisotopes of $^{60}Co$ and $^{137}Cs$ at the specimen preparation.

• Journal of the Korean Vacuum Society
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• v.22 no.4
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• pp.181-187
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• 2013

$Dy^{3+}$-doped $BaMoO_4$ phosphor powders were synthesized by using the solid-state reaction method and their crystalline structure, morphology and size of particles, excitation and emission properties were investigated. The structure of all the phosphor powders, irrespective of the mol ratio of $Dy^{3+}$ ions, was found to be the tetragonal system with the main diffraction peak at (112) plane. The grain particles agglomerate together to form larger clusters with increasing the mol ratio of $Dy^{3+}$ ions. The excitation spectra were composed of a broad band centered at 293 nm and weak multiline peaked in the range of 230~320 nm, which were due to the transitions of $Dy^{3+}$ ions. The emission of the phosphors peaking at 666 and 754 nm, originating from the transitions of $^4F_{9/2}{\rightarrow}^6H_{11/2}$ and $^4F_{9/2}{\rightarrow}^6H_{9/2}$ of $Dy^{3+}$ ions, was rather weak, while the intensity of blue and yellow emission peaking at 486 nm and 577 nm due to the transitions of $^4F_{9/2}{\rightarrow}^6H_{15/2}$ and $^4F_{9/2}{\rightarrow}^6H_{13/2}$ of $Dy^{3+}$ ions was significantly stronger. The experimental results suggest that the white-light emission can be realized by controlling the yellow-to-blue intensity ratio of $Dy^{3+}$ emission.

• Journal of the Mineralogical Society of Korea
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• v.21 no.3
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• pp.247-259
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• 2008

$TiO_2$ coatings on kaolinite powders by sol-gel method were carried out using mixture of titanium isopropoxide, ethanol as solvent, HCl as a catalyst and $H_{2}O$ for hydrolysis. The mole ratio of reaction mixture, stirring time. aging time, crystallization time and crystallization temperature influenced to the crystallization of $TiO_2$ coated on kaolinite and metakaolinite Powders. Optimum condition for $TiO_2$ coatings on kaolinite was as follows; TIP 0.1 mol, $H_{2}O$ 0.15 mol, HCl 0.005 mol, ethanol 100 ml, raw kaolinite 50 g, stirring time 4 hrs, aging time 24 hrs, crystallization time 2 hrs and crystallization temperature $1050^{\circ}C$. The crystallinity of the anatase under optimum condition was about 17.61%. The anatase crystallinity of the $TiO_2$ coated on raw kaolinitc powders (17.61% at $1050^{\circ}C$) was higher at the lower calcination temperature compared with metakaolinite (17.39% at $1200^{\circ}C$).