• Journal of Korean Home Economics Education Association
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• v.17 no.2
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• pp.79-93
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• 2005

The purpose of this was to present the efficient directions of nutrition education for elementary school children. We examined the problems of eating habits. nutrition knowledge, and perception and expectations on nutrition education of elementary school children in school. This study was carried out using a self-administered questionnaire and subjects were 562 elementary school children in Gyeonggi Province. All data in this research was analyzed through SAS program, and the frequency$(\%)$ and the $mean{\pm}S.D.$ on each question were calculated. Data for each group was analyzed according to sex and the difference among the groups were treated for significance by using chi-square test and Student t-test. About $87.6\%$ of the children have a meal over three times a day, and $76.7\%$ answered that they ate at a certain time regularly everyday. Only $69.6\%$ of subjects said that they ate breakfast everyday, showing very high levels of skipping breakfast. The most common frequency of eating snacks was 'once a day' in both sexes(male $52.2\%$, female $48.6\%$). In the perception on the eating habits, $69.3\%$ of children recognized problems on dieting habits, such as unbalanced diet. irregular eating time, and overeating. The perceived and correct knowledge of nutrition were $99.5\%$ and $86.9\%$, respectively. Most of the children$(99.1\%)$ acknowledged that nutrition education need to be carried out in school. And children want to deeply deal with 'cooking', 'growth and nutrition', 'good eating habits', 'nutrition and disease', These results indicated that elementary school children tended to have undesirable eating behaviors, but the rate of children who recognize the importance and the needs of nutrition education in school was high. Therefore, their parents and teachers need to perform continuous education through a curriculum and life instruction so that students have healthy habits by considering what the problems of nutrition habits are, as the elementary students considerably recognize problems of their own dietary habits and needs of nutrition education.

• Journal of Science and Technology Studies
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• v.5 no.1 s.9
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• pp.93-123
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• 2005

This work has following two research goals. First, IVF treatments that have been recently going on in Korea are reexamined from the perspective of women's reproductive rights. Second, the intimate connection between IVF and therapeutic cloning research, in that remnant embryos and eggs that have been secured through IVF treatments have served as a main source of supply for therapeutic cloning research, has been emphasized. The fact that the influencing power of tradition on Korean families and women and IVF techniques eventually joined their hands in support of therapeutic cloning research is noted. Analysis of experiences of infertility by women in the realms of family, medical care during IVF treatment, and therapeutic cloning research that requires continuous supply of eggs leads to following conclusions. First, in the realm of family, infertile women were not only relegated to the status of abnormality but pressured to question their own womanhood. Under this circumstance, IVF treatment helped to reinforce the traditional concept of biological motherhood, thus categorizing married women giving birth to babies and married women who can't or refuses to do so to 'normal ones' and 'abnormal ones' respectively. Second, in the realm of medical care an infertile woman could rediscover her own body during the process of IVF treatment. By going through the processes of hormone treatment, implantation, conception, miscarriage, and so on, she could realize that her own body is understood in diverse ways to her, her family, and the medical profession. Third, in the realm of the state, IVF treatment that was serving as the main supplier of research materials for therapeutic cloning research has been able to avoid controversy in public discourses since the latter has emerged as a signifier of new national economic workhorse for the 21st century. As therapeutic cloning research went into high gear, the status of women as egg providers began to assume a political dimension. Women as egg providers are called upon to take on a paradoxical role as patriotic contributors to national economy on the one hand and as guardians of sacred 'life' on the other hand. The direction and progress of the research will depend on the ways that women comply, compromise, and/or resist the contradiction brought about by being assigned to assume these two identities: the one as a member of the nation requested to serve as a part of national economic development project, even though considered ineligible for financial recompense, and the other one as a guardian of sacred 'life,' even though she have to serve the research that is allowed to create a 'life' to destroy a 'life.'

• Korean Chemical Engineering Research
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• v.50 no.6
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• pp.1068-1075
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• 2012

Poly(butylene terephthalate) (PBT)/Nylon6,12 core/shell micro fiber were prepared by extrusion molding. To investigate their optimum extrusion conditions, compatibility of PBT/Nylon6,12 blend micro fiber in conformity to their weight ratio and manufacture temperature was explored with SEM morphology and DSC. The alterations in their mechanical properties by extrusion speed were compared and analyzed through a UTM. In comparison with SEM figures, the domain sizes of Nylon6,12 were gradually declined by increasing the extrusion temperature of blends. Furthermore, according to these SEM images, the phase separation between Nylon6,12 domain and PBT matrix became indistinct with increasing of weight percentage of Nylon6,12. In case of DSC, the boundaries of two peaks were almost disappeared when increasing the extrusion temperature and also intervals of each two melting peaks became narrow as increasing the Nylon6,12 ratio. The mechanical properties including tensile strength, elongation, flexural strength and flexural modulus were increased as the increase in the extrusion temperature until $260^{\circ}C$. However, the mechanical properties were actually deteriorated over $260^{\circ}C$. The tensile strength, elongation, flexural strength and flexural modulus at $260^{\circ}C$ were 560 $kg_f/cm^2$, 220%, 807 $kg_f/cm^2$ and 22,146 $kg_f/cm^2$, respectively. These values are more than intermediate values of mechanical properties of PBT and Nylon6,12. These results mean that there is compatibility between PBT and Nylon6,12. Based on the extrusion conditions that produced optimum compatibility of blend, as a result, our group obtained micro fibers with the core/shell structure.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.9B
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• pp.610-618
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• 2005

As developed Internet and Computer Capability, Many Users take the many information through the network. So requirement of User that use to network was rapidly increased and become various. But it spend much time to accept user requirement on current network, so studied such as Active network for solved it. This Active node on Active network have the capability that stored and processed execution code aside from capability of forwarding packet on current network. So required execution code for executed packet arrived in active node, if execution code should not be in active node, have to take by request previous Action node and Code Server to it. But if this execution code take from previous active node and Code Server, bring to time delay by transport execution code and increased traffic of network and execution time. So, As used execution code stored in cache on active node, it need to increase execution time and decreased number of request. So, our paper suggest ANC caching technique that able to decrease number of execution code request and time of execution code by efficiently store execution code to active node. ANC caching technique may decrease the network traffic and execution time of code, to decrease request of execution code from previous active node.

• Journal of the korean academy of Pediatric Dentistry
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• v.33 no.4
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• pp.661-672
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• 2006

This study was performed to compare the shear bond strength of AQ Bond $Plus^{TM}$ with AQ $Bond^{TM}$ and Single $Bond^{TM}$. Also by observing the fractured interface under scanning electro-microscope, the fracture pattern and the quality of hybrid layer were analyzed. The possibility of clinical application of all-in-one system which has an advantage to reduce chair time for children with difficult behavior pattern was evaluated, The results obtained are as follows ; 1. There was no significant difference between AQ $Bond^{TM}$ and AQ Bond $Plus^{TM}$ in shear bond strength and Single Bond showed the highest bond strength with statistical significant difference (p<0.05). 2. Adhesive fracture pattern was mainly observed in both enamel/dentin in AQ $Bond^{TM}$ and AQ Bond $Plus^{TM}$ group while Single Bond group showed equal numbers for cohesive and adhesive pattern. 3. Under scanning electro-microscope, resin tags observed in AQ $Bond^{TM}$ and AQ Bond $Plus^{TM}$ were very weak and tangled while strong and thick tags were shown with many lateral branches in Single Bond. Careful case selection and accurate clinical application is recommended when using AQ $Bond^{TM}$ and AQ Bond $Plus^{TM}$considering the result showing its weaker strength than Single $Bond^{TM}$.

• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.3
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• pp.527-533
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• 2004

One clinical technique recommended for improving marginal integrity is "rebonding" or application of unfilled resins to the surface of composite restoration. But continuously the restorations are affected with occlusal load. There is room for doubt that the rebonding agent has the positive effect on microleakage in spite of the stress generated by the occlusal load. This study determined the effect of rebonding on microleakage of Class V resin composite restorations under load cycling. Class V cavities were prepared on the buccal surface of 40 sound extracted premolars and restored with a hybrid light-cured resin composite according to manufacturers' directions. They were randomly divided into two groups consisting of 20 samples: a control(group I), without surface sealing, and the other group(group II) in which margins were etched and rebonded. After thermocycling, each of groups was divided into subgroups(group A, B), and load cycling(total 100,000 cycles with 4-100N load at a rate of 1 Hz) were applied on the group B. Assessment of microleakage utilized methylene blue dye penetration. The following results were obtained: 1. In the occlusal region, no significant difference was noted in the scores regardless of whether or not the rebonding agent was used(group TA-IIA, IB-IIB)(p>0.05). 2. In the cervical region, the control group with rebonding(group IIA) showed the better result than the group without rebonding(group IA)(p<0.05). 3. In the cervical region, the rebonded group with load cycling(group IIB) showed similar results to the group without rebonding(group IB) and no significant difference was noted(p>0.05).

• Journal of the korean academy of Pediatric Dentistry
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• v.36 no.3
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• pp.440-447
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• 2009

This study was performed to compare the wear resistance of sealant and flowable resins for analyzing the effect of flowable resin as a sealant in preventive resin restorations. Specimens were made and Vicker's hardness number and surface roughness were measured. SEM observations of the polished and abraded surfaces were established. Kruskal-Wallis rank test and Mann-Whitney U test at the significant level of ${\alpha}$=0.05 were used. The following results were obtained: 1. The microhardness was decreased among groups in following order: Z350 (3M ESPE, U.S.A), Estelite (Tokuyama Dental, Japan) and Ultraseal (Ultradent, U.S.A). There were significant differences in all groups (p<0.0001). 2. The surface roughness was decreased among groups in following order: Ultraseal XT plus, Palfique Estelite LV and Filtek Z350 flowable. However, there is no statistically significant differences in roughness among Estellite, Z350 and Ultraseal at the significance level of ${\alpha}$=0.05, with p=0.116 3. SEM observation of the unworn and worn surfaces revealed the qualitative differences in the wear appearance among groups. The results in this study indicate that flowable resin is better than sealant in aspect of physical properties.

• Journal of the Korean Electrochemical Society
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• v.10 no.2
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• pp.132-140
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• 2007

The phase-shift method and correlation constants for studying a linear relationship between the behavior ($-{\varphi}\;vs.\;E$) of the phase shift ($0^{\circ}{\leq}-{\varphi}{\leq}90^{\circ}$) for the optimum intermediate frequency and that (${\theta}\;vs.\;E$) of the fractional surface coverage ($1{\geq}\theta{\geq}0$) have been proposed and verified to determine the Langmuir, Frumkin, and Temkin adsorption isotherms (${\theta}\;vs.\;E$) at noble metal/aqueous electrolyte interfaces. At an Ir/0.1 M KOH aqueous electrolyte interface, the Langmuir and Temkin adsorption isotherms (${\theta}\;vs.\;E$), equilibrium constants ($K=3.3{\times}10^{-4}\;mol^{-1}$ for the Langmuir and $K=3.3{\times}10^{-3}{\exp}(-4.6{\theta})\;mol^{-1}$ for the Temkin adsorption isotherm), interaction parameter (g = 4.6 for the Temkin adsorption isotherm), and standard free energies (${\Delta}G_{ads}^0=19.9kJ\;mol^{-1}\;for\;K=3.3{\times}10^{-4}\;mol^{-1}$ and $16.5<{\Delta}G_{\theta}^0<23.3\;kJ\;mol^{-1}\;for\;K=3.3{\times}10^{-3}{\exp}(-4.6{\theta})\;mol^{-1}\;and\;0.2<\theta<0.8$) of H for the cathodic $H_2$ evolution reaction are determined using the phase-shift method and correlation constants. The inhomogeneous and lateral interaction effects on the adsorption of H are negligible. At the intermediate values of ${\theta},\;i.e,\;0.2<{\theta}<0.8$, the Temkin adsorption isotherm (${\theta}\;vs.\;E$) correlating with the Langmuir or the Frumkin adsorption isotherm (${\theta}\;vs.\;E$), and vice versa, is readily determined using the correlation constants. The phase-shift method and correlation constants are accurate and reliable techniques to determine the adsorption isotherms (${\theta}\;vs.\;E$) and related electrode kinetic and thermodynamic parameters(K, g, ${\Delta}G_{ads}^0, {\Delta}G_{\theta}^0$).

• Journal of Bio-Environment Control
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• v.4 no.1
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• pp.50-58
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• 1995

These studies were carried out to develop a system for non -destructive and continuous measurement of fresh weight and to analyse the growth response of leaf lettuce under the different nutrient solution and light condition with this system. The developed measurement system was consisted of four load cells and a microcomputer. The output from the system was highly positive correlation with the plant fresh weight above the surface of the hydroponic solution. The top fresh weight of plant could be measured within the error $\pm$ 1.0g in the range of 0 - 2000g. The top fresh weight of leaf lettuce increased 44 times at 18th day after transferring to the nutrient solution, and the maximum growth rate was observed at 13th day after transferring. The growth rate was 10.7- 29.6% per day during 18 days. Optimum concentration of the nutrient solution for the growth of lettuce was 1.4 - 2.2 mS/cm of EC level. When the light condition was changed from dark to light, the fresh weight was temporarily decreased, but the fresh weight increased under the opposite condition. Top fresh weight of leaf lettuce in the darkness normally increased within 12 hours after darkness treatment, and then slowly increased until 78 hours under continuous dark condition. After that times, the fresh weight began to decrease.

• Journal of Mushroom
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• v.2 no.2
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• pp.88-96
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• 2004

This study was executed to decide the physiological characteristics of Ferule mushroom. Four strains of Ferule mushroom were tested to select a superior strain in its mycelial growth. The pertinent substrates, temperature and pH ranges for the growth of selected strain were determined. And then, the wood rotting ability and type of the Ferule mushroom were determined. The superior strain F-2 among four strains was selected, on the basis of its vegetative mycelial growth and density on agar media. Mycelial growth of F-2 was the best on MYPA among other tested synthetic or semi-synthetic media. The temperature range for pertinent mycelial growth was about $25{\sim}34^{\circ}C$ and best at $30^{\circ}C$. The optimum pH range on MYPA was 5.0~6.0. The mycelial growth was mostly stimulated by soluble starch at cont. 1% (w/w) and secondly, maltose among several carabon sources and by mixed solution of YE(0.25%) and ME(0.25%) but not by ME alone. Cell thining and erosion of Pinus rigida wood by the mycelia of Ferule mushroom were found only on a few cell but largely at wood block test, indicating that the softwood rotting ability of Ferule mushroom mycelia was not so good. The result of polarized light microscopy appeared that cellulose of some tracheides showing the S3 layer lost brifringence was degraded by Ferule mushroom. But only part of cellulose of P. rigida wood was degraded by Ferule mushroom, because most of wood cells continued to showing briefingence. A largely degraded ray parenchyma and longitudinal parenchyma cell and partly thinning and erosion of hardwood(Quercus serrata) cell was found and it indicates that the rotting ability of Ferule mushroom mycelia on hardwood was higher than on softwood. It could be concluded that the difference in the wood rot by Ferule mushroom between the hardwood and softwood was made by the difference of chemical constitutions between them, especially in the contents and the types of lignin. Ferule mushroom was considered as white rotter as a result of bavendam test, although more research should be required.