• Journal of the Computational Structural Engineering Institute of Korea
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• v.19 no.4 s.74
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• pp.429-440
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• 2006

This paper comprises two specific objectives. The first is to examine the applicability of ordinary kriging interpolation(OK) to the p-adaptivity of the finite element method that is based on variogram modeling. The second objective Is to present the adaptive procedure by the hierarchical p-refinement in conjunction with a posteriori error estimator using the modified S.P.R. (superconvergent patch recovery) method. The ordinary kriging method that is one of weighted interpolation techniques is applied to obtain the estimated exact solution from the stress data at the Gauss points. The weight factor is determined by experimental and theoretical variograms for interpolation of stress data apart from the conventional interpolation methods that use an equal weight factor. In the p-refinement, the analytical domain has to be refined automatically to obtain an acceptable level of accuracy by increasing the p-level non-uniformly or selectively. To verify the performance of the modified S.P.R. method, the new error estimator based on limit value has been proposed. The validity of the proposed approach has been tested with the help of some benchmark problems of linear elastic fracture mechanics such as a centrally cracked panel, a single edged crack, and a double edged crack.

• Korean Journal of Animal Reproduction
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• v.26 no.3
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• pp.275-289
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• 2002

The objective of this study was to develop an in vitro assessment of sperm fertilizing capacity of bulls and investigate the factors influencing sperm function and characteristics of frozen-thawed bovine spermatozoa. in vitro fertilization (IVF), the evaluation of motility and normal morphology, HOST (hypoosmotic swelling test), Ca-ionophore induced acrosome reaction, luminol and lucigenin-dependent chemiluminescence for the measurement of reactive oxygen species (ROS), the measurement of malondialdehyde formation for the analysis of lipid peroxidation (LPO), and the evaluation of DNA fragmentation using the method of 747-mediated nick end labelling (TUNEL) by flow cytometry were performed in frozen-thawed bovine spermatozoa. Correlations between the rates of fertilization, blastocyst formation after IVF and the values of respective assays were investigated. 1. IVF rate and blastocyst formation rate averaged 64.4% and 34.3% for spermatozoa from high -fertility bull group and averaged 18.5% and 6.2% for spermatozoa from low-fertility bull group, respectively. There were significantly different between two bull groups. Sperm motility and percentage acrosome reaction averaged 79.0% and 66.2% for spermatozoa from high-fertility bull group and averaged 40.7% and 22.9% for spermatozoa from low-fertility bull group, respectivitely. There were not different between two bull groups. 2. Luminol depenent chemiluminescence, LPO and DNA fragementation averaged 6.4, 2.0 nmol and 2.6% from spermatozoa from high-fertility bull group and averaged 6.5, 3.1 nmol and 7.4% for spermatozoa from low-fertility bull group, respectively. There were significantly different between two bull groups. There was no significant difference in lucigenin dependent chemiluminescence between two bull groups. 3. Fertilization rate was positively correlated with motility and the rate of Ca-ionophore induced acrosome reaction, but negatively correlated with the frequency of luminol-dependent chemiluminescence, the rate of LPO, and the percentage of sperm with DNA fragmentation. There was no correlation between fertilization rate and the percentage of swollen spermatozoa, normal morphology, and the frequency of lucigenin-dependent chemiluminescence. 4. Blastocyst formation rate was positively correlated with the rate of Ca-ionophore induced acrosome reaction, but negatively correlated with the frequency of luminol-dependent chemiluminescence, the rate of LPO, and the percentage of sperm with DNA fragmentation. There was no correlation between blastocyst formation rate and motility, the percentage of swollen spermatozoa, normal morphology, and the frequency of lucigenin-dependent chemiluminescence. In conclusion, these data suggest that ROS significantly impact semen quality. The assays of this study may provide a basis fur improving in vitro assessment of sperm fertilizing capacity.

• Journal of Embryo Transfer
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• v.21 no.3
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• pp.177-182
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• 2006

This study was conducted to investigate the effects of melengesterol acetate (MGA) and $PGF_{2{\alpha}}$ administrations on serum progesterone level, synchrony of estrus and conception rates in Han-woo. Firstly, ten heifers and one freematin were fed 0.5 mg MGA/day for 14 days in a grain carrier, and after 19 days of MGA feeding, a single injection of 25 mg $PGF_{2{\alpha}}$ were treated. Blood samples were collected to evaluate serum progesterone concentrations from the start of feeding of MGA until the end of feeding and subsequent estrous detection and artificial insemination (AI) at 3 days intervals, and on days of $PGF_{2{\alpha}}$ injection, estrous detection, AI, and 15th and 60th days after AI. The level of progesterone in the blood began to increase from 7 days after MGA feeding, and 9 days after feeding it became 5.4 ng/ml and maintained that level thereafter. On the 33th day when the $PGF_{2{\alpha}}$ was injected, it reached the peak level of 7.6 ng/ml. However, 2-3 days after $PGF_{2{\alpha}}$ injection, it dropped to 1.4 ng/ml drastically (p<0.05). Secondly, one hundred and ninety four Hanwoo heifers or cows were divided into two groups to compare estrous induction and conception rates: the one treated with MGA and $PGF_{2{\alpha}}$, (n=104) and the other with $PGF_{2{\alpha}}$ treatment (two injections at 11 days interval, n=90). The heifers or cows treated with MGA and $PGF_{2{\alpha}}$ were identical to those used as above. The percentages of heifers or cows showed estrus were higher in the $MGA+PGF_{2{\alpha}}$ treatment (91.3%) than in the $PGF_{2{\alpha}}$ treatment (72.2%, p<0.05). Conception rates were also higher in the $MGA+PGF_{2{\alpha}}$ treatment (94.2%) than in the $PGF_{2{\alpha}}$ treatment (88.9%, p<0.05). The results of this experiment indicate that estrus synchronization using $MGA+PGF_{2{\alpha}}$ is more effective than that using $PGF_{2{\alpha}}$ (two injections) in Hanwoo.

• The Journal of the Korea Contents Association
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• v.17 no.4
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• pp.468-477
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• 2017

The purpose of this study was to exam nursing students to verify the effects of self-directed learning readiness, teacher-student interaction, educational performance, stress and learner motivation on learner satisfaction. The study population consisted of second and third year nursing students at E university located in S city. Data were collected between June 15, 2016 to June 24, 2016, and questionnaire comprised items to measure general characteristics, learner motivation, teacher-student interaction, self-directed learning readiness, educational performance, and learner satisfaction. A total of 132 students were included for the final analysis. Learner satisfaction was positively correlated with self-directed learning readiness (r= .21, p= .018), teacher-student interaction (r= .39, p<.001), educational performance (r= .21, p= .014), and learner motivation (r= .75, p<.001). In addition, learner motivation was positively correlated with self-directed learning readiness (r= .24, p= .005), teacher-student interaction (r= .38, p <.001), and educational performance (r= .21, p= .018). Finally, learner motivation and teacher-student interaction were found to explain 59.7% of the variance of learner satisfaction. Our findings suggest strategies and interventions that boost learner motivation and teacher-student interaction which are required to improve learner satisfaction in nursing education.

• Korean Journal of Psychosomatic Medicine
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• v.11 no.1
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• pp.60-68
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• 2003

Objectives: The purpose of this study was to develop a Korean version of the Levels of Emotional Awareness Scale(LEAS-K) and to examine its validity and reliability. Methods: LEAS-K was developed from translating original LEAS into Korean. The subjects were 476 Korean medical students(322 males and 154 females). The internal consistency was evaluated with the Cronbach's alpha coefficients and 40 protocols were independently scored by two raters to confirm interrater reliability. Additionally, a Korean version of 20-item Toronto Alexithymia Scale(TAS-20K), Korean versions of the Openness to Experience Inventory(OE), the Marlowe-Crowne Scale (MCS), the Bendig short form of the Taylor Manifest Anxiety Scale(TMAS) and the Emotional Expressivity Scale(EES) were rated to evaluate concurrent validity. Results: The internal consistency measured by Cronbach's alpha was 0.81 and interrater reliability was high{r(40)=0.99}. Correlation coefficients for concurrent validity were nonsignificant with TMAS and EES. LEAS-K correlated significantly with TAS-20K{r(476)=-0.10, p<0.05}, OE {r(476)=0.10, p<0.05} and MCS {r(476)=0.10, p<0.05}. Conclusion: LEAS-K was demonstrated to have high reliability and validity.

• Nuclear Medicine and Molecular Imaging
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• v.42 no.4
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• pp.275-284
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• 2008

Purpose: We intended to evaluate myocardial oxygen consumption ($MVO_2)$ by applying recirculation correction and modified one-compartment model to have a reference range of $MVO_2$ in normal young population and to reveal the effect of recirculation on time-activity curve (TAC). Materials and Methods: In nine normal male volunteers with mean age of $26.3{\pm}4.0$, $MVO_2$ was estimated with 925 MBq (25mCi) of $^{11}C$-Acetate (Neuroscience Research Institute, Gachon University of Medicine and Science, Incheon, Korea) and PET/CT (Biograph 6, Siemens Medical Solution, Germany). Analysis software such as $MATLAB^{(R)}$ v7.1 (Mathworks, Inc., United States), $Excel^{(R)}$ 2007 (Microsoft, United States), and $SPSS^{(R)}$ v12.0 (Apache Software Foundation, United States) were used. Twenty three frames were of $12{\times}10$, $5{\times}60$, $3{\times}120$, $2{\times}300's$ duration, respectively. The modified one-compartmental model and the recirculation correction method were applied. Statistical analysis was performed by using Test of Normality, ANOVA and Post-Hoc (Scheffe's) analysis, and p-value less than 0.05 was considered as significant. Results: The normal reference ranges of $MVO_2$ were presented as $3.18-4.64\;{\times}\;10^{-4}\;ml/g/sec$, $1.91-3.94\;{\times}\;10^{-4}\;ml/g/sec$, $4.31-6.40\;{\times}\;10^{-4}\;ml/g/sec$, $2.84-4.53\;{\times}\;10^{-4}\;ml/g/sec$ and $3.42-5.00\;{\times}\;10^{-4}\;ml/g/sec$ in the septum, the inferior wall, the lateral wall, the anterior wall and the entire wall, respectively. In addition, it was noted that the dual exponentiality of the clearance curve is due to the recirculation effect and that the characteristic of the curve is essentially mono-exponential. Conclusion: $^{11}C$-Acetate is a radiotracer worthwhile to assess $MVO_2$. Re-circulated $^{11}C$ can influence TAC of $^{11}C$ in myocadia and so the recirculation correction must be considered when measuring $MVO_2$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.11
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• pp.1427-1434
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• 2008

This study was aimed to compare nutrition knowledge, dietary attitude and habit of elementary school children with and without education. Eighty-four subjects with unbalanced eating behavior were selected and assigned to either control or education group. The subjects in education group participated in a nutrition education program once a week for 8 weeks. The contents of nutrition education were on food tower, balanced nutrition, nutrient function, food group, importance of breakfast, and nutrition label, etc and the program was performed by a school dietitian. The effects of education was assessed by self-administered questionnaire prior to and after nutritional education. Nutrition knowledge except on snack, dietary self-efficacy except on low fat/ low calorie, attitude except on functional food and favorite, and general dietary habits of children in education group were significantly improved while those in control group showed no changes. Also, factors for unbalanced eating was improved by nutrition education indicating the need for correction on unbalanced eating was diminished. However, children's adherence to snack, instant and fast food remained to be corrected. The dietary habit of balanced eating was improved by education reducing the percentage of unbalanced eating on grain and meat.fish.milk groups. The nutrition education appears to be effective to provide nutrition knowledge thereby to improve dietary attitude, dietary self-efficacy, and partly to reduce children's unbalanced eating factor.

• The Korean Journal of Food And Nutrition
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• v.11 no.1
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• pp.87-98
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• 1998

This study was conducted to investigate Osteoporosis on the effect of dietary factors and past young age period's dairy products consumption on BMD in 170 postmenopausal Korean women without diagnosed disease. Bone mineral density(BMD) of lumbar spine was investigated by dual energy X-ray absorptiometry. Dietary assesment of the subjects were measured by Cognitive Food Frequency Recall method. The measurements of group average were 57.9kg of body weight, 36.73 of BMI(Body Mass Index), 2103.3㎉ of energy, 638.7mg of dietary calcium, 70.3g of protein, and 10.58mg of iron. Nutrient intake levels were similar to or more than the level of Korean Recommended Dietary Allowances. Bone Mineral Density(BMD) of Lumbar spine(L2-L4) of group average was 0.912g/$\textrm{cm}^2$, and under 50 yr's 1,02g/$\textrm{cm}^2$, 50~54 yr's 0.92g/$\textrm{cm}^2$, 55~59 yr's 0.85g/$\textrm{cm}^2$, over 60 yr's 0.85g/$\textrm{cm}^2$, had been getting low degree on aging. BMD of the Lumbar spine was positively correlated with calorie, body weight, dietary calcium, protein, phosphorus and serum albumin. Past dairy products consumption experiment was highly significant on BMD in teenage period(R square = 26, p-value 0.0031). Particularly in over 60 yr group, the correlations between BMD and past dairy products consumption in teenage period had shown highly significance(r=0.48, p<0.02). 55~59 yr age group had also positive correlation(R squae = 0.29, p<0.05). This results confirm that the most effective way of preventing osteoporosis and the fractures is to maximize peak bone mass in early life and to minimize bone loss through the balanced intake of Ca and other nutrients and regular physical activity.

• Korean Journal of Animal Reproduction
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• v.25 no.2
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• pp.163-169
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• 2001

OSBA(oocytes-sperm binding assay) is a tool developed for rapid test of optimal condition of IVF medium and protein source by binding ability of mouse sperm and egg. Mouse oocyte-cumulus complexes were prepared by removing of the cumulus cells with 0.1% hyaluronidase. 10$\pm$2 oocytes per 30 ${mu}ell$ medium drop were inseminated with 3 ${mu}ell$ sperm suspension and were cultured f3r 3 hours and 24 hours, respectively. And the oocytes were recovered gently and the No. of sperm bound on oocytes were counted. In the Exp. 1, the ratio of oocytes bound with one sperm at least were 60.2%(50/83), 2%(2/77) and 100%(79/79) in the medium with no protein, FBS(15%, v/v) and BSA(0.4%. w/v), respectively, Fetal bovine serum(FBS) seriously inhibited sperm binding on oocyte, although bovine serum albumin(BSA) promoted the binding ability. The inhibiting effect of FBS was dependent on the concentration of FBS. The sperm binding ability according to oocyte maturity was tested in the Exp. 2. There was no significant difference between Met. II (mature) and Met. I (intermediate mature) oocytes in the number of oocytes bound with sperm and the number of sperm bound on oocytes. Finally, in Exp. 3, two batches of Ham's F10 medium with good and poor quality by OSBA were tested (The ratios of embryos developed from PN 1-cell stage to hatched blastocyst; 25% vs. 70%). In the medium with good quality, sperm binding ability was significantly increased (P ＜ 0.05). The ratio of oocytes bound with one sperm at least was 66% and 90% in the medium with poor and good quality, respectively. Conclusively, It was possible to test IVF medium condition rapidly and easily by OSBA.

• Korean Journal of Poultry Science
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• v.40 no.3
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• pp.171-178
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• 2013

The purpose of this study was to evaluate the sperm viability, normal acrosome and mitochondrial activity in the frozen-thawed fowl semen by different cryoprotectants. The experiment was carried out on 10 sexually adult roosters of Ogye. The semen was collected twice a week and pooled semen was diluted 1:1 EK extender containing no cryoprotectant at $5^{\circ}C$. After equilibration for 30 minutes, diluted chicken semen was diluted 1:1 extender containing either 7% dimethylacetamide (DMA), 7% dimethylformamide (DMF) or 7.5% methylacetamide (MA) at final concentration and was put in 0.5 mL plastic straws and frozen for 30 minutes by exposure to liquid nitrogen vapor 4 cm above the surface of liquid nitrogen, followed by plunging into liquid nitrogen. Frozen semen was thawed in water bath at $5^{\circ}C$ for 2 minutes. For cytometric analysis, the frozen-thawed semen was diluted with EK extender to a final concentration of 90 million spermatozoa per mL. Sperm membrane integrity was evaluated as SYBR-14 and propidium iodide (PI). Acrosome integrity was assessed with fluorescein isothiocyanate-labeled PSA and PI. The percentage of mitochondrial function was estimated by using Rhodamine123 (R123) and PI. In conclusion, freezing rooster semen by using 7% DMF as cryoprotectant was significantly highest in rates of survival and mitochondrial function while its rate of damage of acrosome was significantly lowest. As a result, DMF is the cryoprotectant that has the lowest influences on sperm membranes and acrosome integrity. Therefore it could be used for freezing method of animal genetic conservation method for poultry diversity.