• Journal of the Korean Society of Food Culture
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• v.13 no.2
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• pp.107-118
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• 1998

A nutrition education program for teachers and caregivers of the preschool children can be most effective when it is based on a comprehensive needs assessment dealing with sociodemographic factors, dietary habits, and nutrition. The purpose of the present study was to investigate current dietary habits and nutrition knowledge of the teachers and caregivers of the day-care centers. Two hundred forty two teachers and caregivers were administered a questionnaire which was designed to ascertain informations on sociodemographic data, dietary habits and nutrition knowledge. Dietary habits of the teachers were found to be significantly different by sociodemographic variables; breakfast skipping/meal irregularities (age, p=0.011); frequency of snacking (education level p=0.031); preference for salty taste(age, p = 0.000, marital status p=0.038); preference for sweet tarte (age p=0.009); preference for vegetables (income level p=0.050); frequency of eating out (age p=0.028, marital status p=0.001); frequency of coffee drinking (age p=0.019). Daycare center teachers' nutrition knowledge level was found to be less than adequate expecially on nutrients that are liable to be deficient in young growing children and their food sources. Proportions of the teachers who answered correctly to the questions on foods rich in vitamin A, iron content of milk, bioavailability of calcium in plant foods were as low as 20.2%-54.5%. The most frequently used sources of nutrition information were mass media such as TV, radio, newspaper and magazines. Only 2.9% of the subjects reported that they obtain nutrition information from health professionals such as nutritionists/dietitians, physicians, and nurses. These findings are applicable at the planning and implementation stages of various nutrition programs for the improvement of dietary habits and nutrition knowledge of the teachers and caregivers of the daycare centers. Further studies are needed to investigate the effects of teachers' dietary of habits and nutrition knowledge on food habits of young growing children.

• Journal of Community Nutrition
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• v.8 no.2
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• pp.102-106
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• 2006

The purposes of this study were to investigate the effects of the popularity of menu items in nutrient consumption of school-aged children participating in a School Breakfast Program. The weighed plate waste method was used to determine the nutrient intake of students. The nutrient intake was evaluated based on the popularity of the menu item, gender, and grades. The average intakes of all nutrients except energy, fiber, and sodium were well within the goals. Actual nutrient intake varied based upon the popularity of $entr{\acute{e}}es$ and the popularity of menu items was a main effect in nutrient content of meals. When the most popular $entr{\acute{e}}es$ were served, school-aged children's energy intake and School Breakfast Program participation rate increased. Saturated fat and sodium intakes also were higher than the goal when the most popular $entr{\acute{e}}es$ were served. The significant main effect was grades for total fat (p < 0.05) and calcium (p < 0.05), which was qualified by the two-way interaction between gender and grades for saturated fat (p < 0.05), protein (p<0.1), iron (p<0.01), vitamin C (p<0.01) and carbohydrates (p<0.001). Gender itself was not a significant main effect. Based on the findings, the suggestions for educating school-aged children on more healthful breakfast food choices and reformulating recipes for the popular $entr{\acute{e}}es$ are made. (J Community Nutrition 8(2): 102-106, 2006)

• Korean Journal of Food Science and Technology
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• v.21 no.6
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• pp.863-868
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• 1989

In comparison of contents of the components related to the quality of kiwifruit depended on the cultivars, the obtained results were as follows; Abbott showed the highest values in soluble solid, crude fat, firmness and specific gravity. Potassium, phosphorus, calcium and magnesium were estimated as the major minerals in kiwifruit and Bruno contained the highest amounts of potassium and magnesium. Bruno also had high concentrations of ascorbic, maleic, citric and fumaric acid when compared with the other cultivars. The changes in chemical components of kiwifruit (Hayward) by ripening stage were as follows; During ripening, the glucose and fructose contents were increased with decrease of sucrose content. Ascorbic, maleic, fumaric and succinic acid contents were considerably increased during ripening From the investigation of changes in protein pattern by electrophoresis! the new bands with about 17,000-23,50kd were shown during ripening.

• Journal of the Korea institute for structural maintenance and inspection
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• v.16 no.5
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• pp.59-67
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• 2012

During the manufacturing of Portland cement, CO2 gas is also necessarily produced through both decarbonation of calcium carbonate and kiln burning. By partially replacing the Portland cement with limestone powder, which is an inert filler in a concrete mixture, CO2 consumption can be reduced in a construction field. This study is to investigate the fundamental durability characteristics of limestone powder added concrete. Experimental variable was the replacement ratio of limestone powder from 0% to 25% with 5% increment. Durability characteristics were investigated by resistance to freeze-thaw, alkali-silica reaction and de-icing chemical in addition to the properties of fresh concrete. From test results, it was observed that the addition of limestone powder did not significantly affect the resistance to freeze-thaw reaction and de-icing chemical. The addition of limestone powder reduced the occurrence potential of alkali-silica reaction by reducing an alkali content in Portland cement.

• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.1
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• pp.75-83
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• 2014

In order to prevent brittle failure of concrete, steel fiber reinforcement is effective composite material. However ductility of steel fiber reinforced concrete may be limited due to shrinkage caused by large content of cement binder. Chemical prestressing for steel fiber reinforcement in cement matrix can be induced through expansive admixture and this can increase reinforcing effect of steel fiber. In this study, mechanical performances in concrete with CSA (Calcium sulfoaluminate) expansive admixture and steel fiber reinforcement are evaluated. For this work, steel fiber reinforcement of 1 and 2% of volume ratio and CSA expansive admixture of 10% weight ratio of cement are added in concrete. Mechanical and fracture properties are evaluated in concrete with steel fiber reinforcement and CSA expansive admixture. CSA concrete with steel fiber reinforcement shows increase in tensile strength, initial cracking load, and ductility performance like enlarged fracture energy after cracking. With appropriate using expansive admixture and optimum ratio of steel fiber reinforcement, their interactive action can effectively improve brittle behavior in concrete.

• Korean Journal of Food Science and Technology
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• v.40 no.1
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• pp.47-55
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• 2008

The objectives of this study were: 1) to develop the sensory lexicons of milk marketed in Korea, 2) to investigate the effects of pasteurization and milk composition on the sensory qualities of milk, and 3) to evaluate the correlation between descriptive analysis and the electronic nose method. Electronic nose and descriptive analyses were conducted to analyze the sensory characteristics of 14 milk samples. The 14 samples were provided from 4 manufacturers with different pasteurization methods, and varied in fat, calcium, and lactose content. Twenty-six sensory lexicons were developed to describe the sensory characteristics of the samples. The low temperature, long-time processed milk had a distinctive 'bi-rim' flavor regardless of the milk composition. The lactose-free milks were sweet, and the low-fat milks had relatively low intensities for most flavor attributes. The electronic nose method successfully grouped the milk samples primarily based on their composition, but grouped them weakly by pasteurization method.

• Horticultural Science & Technology
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• v.32 no.5
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• pp.614-622
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• 2014

Melons (Cucumis melo L.) are generally grafted onto Cucurbita rootstocks to manage soilborne pathogens such as Monosporascus root rot and v ine decline (MRR/VD) and Fusarium wilt. However, g rafting onto Cucurbita rootstocks reportedly results in the reduction of fruit quality. In this study, the resistance to MRR/VD, yield, and fruit quality of melons grafted onto melon rootstocks were evaluated under greenhouse conditions. Eight melon rootstocks (R1 to R8) were used and the inodorus melon 'Homerunstar' was used as scion. Melon rootstocks R1 to R6 were selected based on resistance to MRR/VD under greenhouse conditions. Non-grafted 'Homerunstar' and plants grafted onto squash interspecific hybrid 'Shintozwa' rootstock (Cucurbita maxima D. ${\times}$ C. moschata D.) served as controls. Grafted melons were cultivated in the greenhouse infested with Monosporascus cannonballus during two growing seasons (summer and autumn). The responses to MRR/VD, yield, and fruit quality differed depending on the rootstocks and growing season. The melons grafted onto 'Shintozwa' exhibited less severe disease symptoms and higher survival rates than non-grafted melons in both seasons. While the melon rootstocks in the summer cultivation did not increase the survival rate compared to non-grafted melons, the melon rootstocks R1 and R2 in the autumn cultivation led to higher survival rates. The melon rootstocks resistant to MRR/VD increased the percentage of marketable fruits and marketable yields. Grafting onto the melon rootstocks caused little or no reduction of fruit quality such as low calcium content, fruit softening, and vitrescence, especially in lower-temperature autumn season. Accordingly, these results suggest that grafting onto the melon rootstocks may increase the tolerance to MRR/VD and the marketable yield without a reduction of fruit quality.

• Microbiology and Biotechnology Letters
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• v.20 no.4
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• pp.437-444
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• 1992

An innovative process for high fructose corn syrup (HFCS) production coupled with direct saccharification of raw corn starch in the agitated bead enzyme reactor (bioattitor) was investigated. The required high concentration/purity of glucose solution suitable for isomerization was produced directly in a bioattritor. without condensation of hydrolyzate, 398 g glucose/$\ell$ and 98% glucose content from 400 g/$\ell$ (w/v) of raw corn starch after 24 hours. The unsaccharified residual starch could be separated easily upon centrifugation, and resaccharified. The obtained solution also possessed other desirable requirements as substrate for isomerization, such as. low concentrations of denatured protein and calcium ions, thereby, simplified the purification step. The obtained glucose solution was isomerized in an enzyme reactor paked with immobilized glucose isomerase to evaluate the suitability as a substrate. The proposed new HFCS process seems to have many advantages over the conventional process via liquefaction-saccharification steps. The follow-up investigations of the proposed process need to be conducted to evaluate the feasibility of industrial application.

• Transactions on Electrical and Electronic Materials
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• v.8 no.6
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• pp.241-245
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• 2007

[ $(Ba_{0.9-x}Sr_xCa_{0.10})TiO_3$ ] (x=0.33, 0.36) powders were prepared by sol-gel method. $(Ba,Sr,Ca)TiO_3$(BSCT) thick films, undoped and doped with $MnCO_3$ and $Yb_2O_3(0.1{\sim}0.7mol%)$, were fabricated by the screen printing method on the alumina substrate. The coating and drying procedure was repeated 6-times. The Pt bottom electrode was screen printing method on the alumina substrate. These BSCT thick films were annealed at $1420^{\circ}C$ for 2 hr in atmosphere. The upper electrodes were fabricated by screen printing the Ag paste and then firing at $590^{\circ}C$ for 10 min. And then the structured and dielectric properties as a function of the doping amount of $Yb_2O_3$ were studied. As a result of the TG-DTA, exothermic peak was observed at around $670^{\circ}C$ due to the formation of the polycrystalline perovskite phase. All BSCT thick films showed XRD patterns of typical cubic peroveskite structure. The average thickness of BSCT thick films was about $70^{\mu}m$. The curie temperature and the dielectric constant decreased with increasing $Yb_2O_3$ doped content and the relative dielectric constant of the specimen, doped with 0.5 mol% $Yb_2O_3$ at BSCT(54/36/10), showed a best value of 5018 at curie temperature.

• Korean Journal of Materials Research
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• v.28 no.5
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• pp.273-278
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• 2018

Lithium-ion batteries have been considered the most important devices to power mobile or small-sized devices due to their high energy density. $LixCoO_2$ has been studied as a cathode material for the Li-ion battery. However, the limitation of its capacity impedes the development of high capacity cathode materials with Ni, Mn, etc. in them. The substitution of Mn and Ni for Co leads to the formation of solid solution phase $LiNi_xMn_yCo_{1-x-y}O_2$ (NMC, both x and y < 1), which shows better battery performance than unsubstituted $LiCoO_2$. However, despite a high discharge capacity in the Ni-rich compound (Ni > 0.8 in the metal site), poor cycle retention capability still remains to be overcome. In this study, aiming to improve the stability of the physical and chemical bonding, we investigate the stabilization effect of Ca in the Ni-rich layered compound $Li(Ni_{0.83}Co_{0.12}Mn_{0.05})O_2$, and then Ca is added to the modified secondary particles to lower the degree of cationic mixing of the final particles. For the optimization of the final grains added with Ca, the Ca content (x = 0, 2.5, 5.0, 10.0 at.%) versus Li is analyzed.