• Bulletin of the Korean Chemical Society
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• v.11 no.1
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• pp.15-19
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• 1990

The crystal structure of $(C_{12}H_{24}O_6{\cdot}K)_2K[Co(OH)_6Mo_6O_{18}]{\cdot}12H_2O$ has been determined by X-ray diffraction. Crystal data as follows ; monoclinic, space group $C_2/m,\;a\;=\;22.512(4)\;{\AA},\;b\;=\;18.304(4)\;{\AA},\;c\;=\;7.641(1)\;{\AA},\;{\beta}\;=\;90.52(2)\;{\AA}$, and Z = 2. A final conventional R value of 0.044 was obtained by least-squares refinement of 4173 independent observed $[{\mid}Fo{\mid}{\geq}3{\sigma}({\mid}Fo{\mid})]$ reflections. The $[Co(OH)_6Mo_6O_}{18}]^{-3}$ polyanion shows the well-known Anderson-structure and has approximate 3m symmetry. A $[Co(OH)_6Mo_6O_{18}]^{-3}$ polyanion is located between two crown ether complexed cations forming a sandwich structure. One potassium ion interacts with the crown ether via electrostatic interactions. The other potassium ion only interacts with the water molecules and terminal oxygen atoms of the polyanion.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.18 no.8
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• pp.1102-1107
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• 1993

Microwave dielectric properties of CaTiO3 and CaTiO3-TiO2 ceramics for the composition range between 40 and 50 mol% CaO in CaO-TiO2 binary system were investigated. CaTiO3 ceramics with50 mol% CaO showed the dielectric constant (e,) of 178, the temperature coefficient of resonant frequency(c,) of+1000 ppm/'c and the qualify factor Q of 2760 (f0=2.7 GHz ). Dielectric constant and temperature coefficient of resonant frequency of ceramics with dual phases of CaTiO3 and TiO2 decreased gradually from those of CaTiO3 as the CaO content decreased. Q value and density were found to have minimum at the composition of 47 mol% CaO. The degradation of Q value and density in dual phase ceramics seems to be caused by the large pores at grain boundaries and/or within grains remained after rapid growth of CaTiO3 grains as TiO2 Phase decreased.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.8
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• pp.540-546
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• 2013

The main purpose of the present study was to establish a quicker and cheaper model for predicting the LHV of MSW based on its wet physical composition being brought into C Incinerator. The one regression model was developed to correlate the energy content with variables from physical composition based on a wet matter. The performance of this model for MSW of the C Incinerator was superior to that of equations developed on a dry matter basis by other researchers for estimating energy content. The applicability of this model at the other 4 incinerators showed also an acceptable precision level.

• The Korean Journal of Ecology
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• v.26 no.5
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• pp.273-280
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• 2003

Saline conditions invoke oxidative stress attributed to the overproduction of reactive oxygen species (ROS). Changes in quantum efficiency and antioxidative enzyme activity upon salt treatment were examined in a salt-tolerant plant, Atriplex gmelini, to test the hypothesis that salt tolerance of A. gmelini is due to the increased activity of antioxidative enzymes. A. gmelini showed optimum growth at 100 mM NaCl producing 116% of the shoot dry weight over control plants in 0 mM NaCl treatment. Healthy growth persisted up to 300 mM NaCl treatment maintaining normal internal water content and dry weight. No photochemical stress or damages on antioxidative defense system was obvious in plants of 2 and 4 day salt treatment which was indicated by increased quantum efficiency (Fv/Fm value), decreased stress index (Fo/Fm value), and increased activity of antioxidative enzymes such as SOD, APX, GR. However, the plants treated with 400 mM NaCl showed decrease in growth and in antioxidative enzyme activity although the enzyme activity was still higher than that of the 0 mM NaCl treated plants (l31%, 114%, and 134% of the SOD, APX, and GR activity, respectively). Interestingly, another important antioridative enzyme that scavenges H₂O₂ in plant cells, CAT, showed rapid decrease in its activity as salt concentration increased; 38%, 22%, 15% of the 0 mM NaCl treated plants at 200, 300, 400 mM NaCl treatments, respectively. It appears that the enzymes in ascorbate-glutathione cycle such as APX and GR play the major roles in scavenging ROS produced by salt stress in A. gmelini. After 6 days of salt treatment, the damage in photochemical and antioxidative defense system was indicated by decreased Fv/Fm value and increased Fo/Fm value. A. gmelini appears to cope with short term salt treatment by enhanced activity of the antioxidative defense system, whereas long term stress invoke oxidative stress by increased ROS due to the damages in photochemical and antioxidative system.

• Journal of Bio-Environment Control
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• v.30 no.1
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• pp.46-55
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• 2021

This experiment was conducted to investigate the effect on chlorophyll fluorescence, stem sap flux relative rate (SFRR) and leaf temperature of cucumber when irrigation is controlled using a soil moisture tensiometer. Cucumber (Cucumis sativus L.) 'Chungchun' was irrigated of 10-10-20 kPa and 20-10-10 kPa by soil starting point of irrigation at each growth stage. At the 66 days after treatment (DAT) of 736 to 854 W·m-2 and above 32℃, chlorophyll fluorescence variables (Fo, Fm, Fv/Fm) values showed significantly different between treatments. The Fo and Fv/Fm value in the daytime (10:30 am to 6:00 pm) at 66 DAT was higher in 20-10-10 kPa treatment than in 10-10-20 kPa treatment. The Fv/Fm value decreased when the leaf temperature was increased. There was no difference in leaf growth (length, width and area) at 28 and 66 DAT, but the chlorophyll content (SPAD value) was significantly higher in 20-10-10kPa treatment. SFRR and leaf temperature increased with light intensity and temperature increased. In both treatments, the SFRR started to increase sharply between 8 am and 9 am when the solar radiation is 170 W·m-2 or higher. The soil temperature of the treatments decreased after irrigation, that showed 31.0℃ at 10-10-20kPa and 28.5℃ at 20-10-10kPa on July 5 (820W·m-2 at 1 pm). However, there was no difference in SFRR, leaf temperature, temperature difference (leaf temperature - air temperature) and VPD between treatments. SFRR was significantly positive correlate with the leaf temperature (p < 0.01, r = 0.770). The SFRR and leaf temperature showed positive significant correlation with solar radiation, temperature, soil temperature, soil moisture content and VPD. There was a negative significant correlation with relative humidity and temperature difference.

• Korean Chemical Engineering Research
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• v.54 no.4
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• pp.510-518
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• 2016

Ethyl cellulose-g-poly(ethylene glycol) (EP) was synthesized by esterification of carboxylic acid functionalized methoxy polyethylene glycol (MPEG-COOH) with ethyl cellulose (EC) in order to develop a hydrophilic substrate for thin-film composite (TFC) membrane in a forward osmosis (FO) system. A porous EP substrate, fabricated by a non-solvent induced phase separation method, was found to be more hydrophilic than the EC substrate due to the presence of polyethylene glycol (PEG) side chains in the EP. Since the EP substrate exhibits smaller water contact angles and higher porosity, the structural parameter (S) of TFC-EP is smaller than that of TFC-EC, indicating that internal concentration polarization (ICP) within porous substrates can occur less when TFC-EP is used as a membrane. For example, the water flux value of the TFC-EP is 15.7 LMH, whereas the water flux value of the TFC-EC is only 6.6 LMH. Therefore, we strongly believe that the TFC-EP could be a promising candidate with good FO performances.

• Korean Journal of Food Science and Technology
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• v.30 no.6
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• pp.1327-1332
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• 1998

The optimum thermal condition of retort Biji product was determined by heat penetration curve, aerobic bacteria count and sensory test. Retort Biji showed a simple logarithmic heating curve regardless of solid content. Heating time was a $26{\sim}27$ min until Fo value reached 9 min and the amount of microorganism in the Biji product sterilized for 26 min at $121^{\circ}C$ were decreased to $10^{-4}\;CFU/g$, indicating the safe range for retort product. The rate of heat penetration was reduced as solid content and size of product were increased, whereas sterilization temperature and initial temperature of product influenced the heat penetration curve. Sensory scare indicated that there was no significant difference in color, flavor, and appearance among different thermal processes. However, Biji product sterilized at $121^{\circ}C$ showed the highest score in overall preference value.

• Journal of the Korean Society of Food Science and Nutrition
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• v.11 no.4
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• pp.17-24
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• 1982

Optimum moisture content of about 60% of cooked rice was obtained by soaking the fully steamed rice with 35% moisture conture content in ambient water temperature$(24^{\circ}C)$ for one hour. Two different levels of package vacuum was used in packing this cooked rice in retort pouch, and the effect of the levels of package vacuum on the texture of the cooked rice in the pouch during thermal process was investigated: Higher sterilization value (Fo value) and steeper slope (fh value) on the heating curve of the thermal process was obtained with the higher package vacuum product. The j value of the heating curves of cooked rice packed in retort pouch was ranged between 0.80 and 1.18 without respect to the levels of the package vacuum and the process temperature. Although in respective of the ratio of the stickiness to the hardness (-H/H) the product with higher package vacuum showed better result, the shape of most of the rice grain in the vacuum vacuum pouch was deformed and Jumped mass of inferior quality than the one in the lower vacuum package.

• The Journal of Industrial Distribution & Business
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• v.13 no.4
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• pp.35-49
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• 2022

Purpose - According to the recently changing consumer smart environment and consumer decision-making process, this study investigates the structural relationship between electronic(online) WOM information characteristics and brand community experience value types on specific brand reliability and brand transformation. In particular, the characteristics of word of mouth information and the experience value of brand community users were divided into detailed fac tors and approached. Methodology - In order to proceed with this study, we review previous studies and setting hypotheses. The hypothesis was verified through a survey that was conducted for the consumers with online consumption activities in less than six months. With reference to previous studies, operational definition was made for the questionnaire design. In order to verify the hypothesis, 282 people were statistically analyzed through the survey This data were used for AMOS for confirm hypothesis established. Results - eWOM information characteristics were classified into usefulness, timeliness and un-bias, and online community experience values were classified into interaction, playfulness, and virtuality. In addition, it is to investigate the relationship between the brand reliability and user's experience value in brad community. The main results are as follows. The first result was that usefulness and un-bias, which are the eWOM information characteristics had a positive effect on forming brand reliability. However, the factor of timeliness did not affect brand reliability. Second, in terms of user experience value and brand reliability in the brand community. It was fo und that experience values such as interaction, playfulness, and vituality all had a positive influence on brand reliability. Third, it was found that brand reliability has a positive influence on the on-line conversion activity of users. Conclusions - Through this study, the field of online consumer behavior research is expanding, and this study suggested that careful management is necessary according to the type or characteristics of eWOM information. Additionally, it presents the importance of the user's empirical value in the brand community influencing brand attitude and reliability. In practice, the implementation of the marketing communication mix in digital marketing has recently been underway to enhance the conversion behavior of users. At this level, it also reveals the preceding factors that increase user conversion behavior.

• Korean Security Journal
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• no.1
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• pp.123-134
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• 1997

Our conuntry have come out to the phenomenon to the atrocity crimes, make into a intellecture crims and specialization with them due to various change to the expension of economy growth, drift of population to cities and sense of value is plunged in confution, Now that things have come to this day, since foundation of the security guard law it first begin, ten years, civilian securities guard law was include to the civil service securities law due to amendment fo the civility secuties law newly on Dec. 30, 1995. According to the amendment, the part of the public peace of peoples livelihood were slough of the visual angle in knowledge which function of the civilies security were only be in under the government dimension were put in order to be tointly according to the such state of affairs, should found the consider a counterplan fundamentally regarding to the what to doing efforts foster the civilities securitylaw and qualitalive elevation of presidential guards. To make a long story short by few words, the question resolves itself into the following five points. The first, peoples arrengements for the attitude fo public duty service with devotedly Sustaining publicity work activities for the thire divert of the understanding of civilian security guard. The secondly, Existing security traders and security association should to support to the civilian security works. The third, The government office concerned should strengthen the licensing system in order to improve the quality of existings in order to may establishment newly systems of license and technical institute of regarding to them. The fourth, Should be newly organixed the exclusive organization of personal protective works in the police buroau for the sustaining development of civirity guard works and soundness of the upbringing. The fifth, It is necessary to found the reserch institute for the study on oretical, scholarly, study for the technical reserch and enlargement of effeciveness And try to find a solution to the Universitys function and duty, activity plan, support plan to the Department of security specialist for the come forward in succession it under the national assistance. The finally, I am sure that the Korean security association could be transiormed into the organization which reliable and receive a love from the peoples when doing best utmost to do pursuit of the structure to be a securitys legalism, specialization and total security systems.