• Journal of the Korea Concrete Institute
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• v.24 no.3
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• pp.293-303
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• 2012

Recently, as construction technology improved, concrete structures not only became larger, taller and longer but were able to perform various functions. However, if extreme loads such as impact, blast, and fire are applied to those structures, it would cause severe property damages and human casualties. Especially, the structural responses from extreme loading are totally different than that from quasi-static loading, because large pressure is applied to structures from mass acceleration effect of impact and blast loads. Therefore, the strain rate effect and damage levels should be considered when concrete structure is designed. In this study, the low velocity impact loading test of steel fiber reinforced concrete (SFRC) slabs including 0%~1.5% (by volume) of steel fibers, and strengthened with two types of FRP sheets was performed to develop an impact resistant structural member. From the test results, the maximum impact load, dissipated energy and the number of drop to failure increased, whereas the maximum displacement and support rotation were reduced by strengthening SFRC slab with FRP sheets in tensile zone. The test results showed that the impact resistance of concrete slab can be substantially improved by externally strengthening using FRP sheets. This result can be used in designing of primary facilities exposed to such extreme loads. The dynamic responses of SFRC slab strengthened with FRP sheets under low velocity impact load were also analyzed using LS-DYNA, a finite element analysis program with an explicit time integration scheme. The comparison of test and analytical results showed that they were within 5% of error with respect to maximum displacements.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.12
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• pp.1929-1936
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• 2014

This study investigated purchasing behaviors of processed foods in high school students (male 94 and female 85) in the Yongin region. Frequency of eating processed foods was generally once (36.9%) or twice (32.4%) a day. Frequency according to processed food items was in the following order: confectionary (31.3%)> beverages (17.3%)> breads (12.3%)> instant noodles (11.7%) and milk or dairy products (11.7%)> frozen desserts (10.6%). The places for purchasing were a big mart (30.7%), convenience store (28.5%), and school cafeteria (26.8%). The reasons for purchasing were 'tasty' at 43.6% and 'hungry' at 35.2%. Main factors affecting purchasing were 'taste' at 70.9%, followed by price (16.2%)> quantity (5.6%)> nutrition (4.5%). The most important parts of food and nutrition labels were 'shelf-life' (67.0%) and 'calories' (57.5%). Degrees of confirmation of food and nutrition labeling were 'always' (12.3%), 'rarely' (28.5%), and 'sometimes' (59.2%). The reasons for not reading labels were 'unconcerned' (27.9%), 'too tiny lettering' (28.5%), 'hard to understand' (16.2%), and 'habitually' (15.1%). These results reflect low attention of high school students towards healthy food choices using food and nutrition labeling during purchasing. In conclusion, a specific education program for providing accurate product information as well as leading healthy purchasing behaviors should be required.

• Journal of the Korean Home Economics Association
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• v.41 no.12
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• pp.53-68
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• 2003

The purpose of this study was to develop lesson plans and teaching materials applying practical reasoning instruction for the 7th home economics curriculum content, and to test the effect of practical reasoning instruction on morality of middle school students. This study is a quasi-experimental research with a pretest-posttest design. Practical reasoning instruction for experimental group and traditionally lecture oriented instruction for comparison group were input, and tested the statistical differences between two groups before and after the treatment. The subjects for this study were 8th grade students of a middle school located in Kwangju city. Two classes of 76 students homogeneous in characteristics and academic record for each experimental and comparison group were assigned. Instrument used for this study was a revised moral indicator, that was developed by KEDI(2001). Spss/win for 10.0 statistics program was used for analysis of data. ANCOVA was done for testing statistical difference between pretest and posttest of experiment group and comparison group. Result of study which showed statistically significant difference between groups were：1. Virtue of "responsibility for words and deeds"(from 3.22 to 3.61 for experimental group and from 3.27 to 3.26 for comparison group) in domain of responsibility and cooperation, and virtue of "punctuality"(from 3.59 to 3.76 for experimental group and from 3.41 to 3.28 for comparison group) in domain of trustworthiness, 2. Virtue of "conversation etiquette"(from 3.47 to 3.67 for experimental group and from 3.28 to 3.31 for comparison group) in domain of caring for others, 3. Virtue of "forgiveness other′s mistakes"(from 3.32 to 3.65 for experimental group and from 3.33 to 3.25 for comparison group) in domain of kindness, concession, forgiveness, and virtue of "volunteering activity"(from 2.89 to 3.71 for experimental group and from 3.36 to 3.45 for comparison group) in domain of compassion and service, 4. Virtue of "equip the convenient facility for handicapped"(from 4.19 to 4.29 for experimental group and from 4.17 to 3.91 for comparison group) in domain of equality and human rights, virtue of "recovering selfness for own community"(from 2.34 to 2.79 for experimental group and from 2.14 to 2.29 for comparison group), virtue of "opposing way of accomplishing purpose by an means"(from 3.27 to 3.31 for experimental group and from 3.47 to 3.05 for comparison group), virtue of "opposing election of considering acquaintance"(from 3.35 to 3.56 for experimental group and from 3.12 to 3.14 for comparison group) in domain of fairness, and virtue of "eradication of military force or violence among countries"(from 3.49 to 3.57 for experimental group and from 3.38 to 3.05 for comparison group) in domain of love for humanity. The morality of experimental group was improved more than that of comparison group in all of above items. From the results of this study, following conclusion was drawn. Practical reasoning instruction in home economics is effective in raising students′ virtue and value of responsibility in words and deeds, trustworthiness in punctuality, courtesy of not interrupting conversation, forgiveness of other′s mistakes, volunteering activity, equity for handicapped, fairness opposing selfness for own community, fairness opposing way of accomplishing purpose by all means, fairness opposing election of considering acquaintance, and love for humanity opposing war.

• Journal of Gastric Cancer
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• v.7 no.1
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• pp.1-8
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• 2007

Purpose: There has been increased the number of early gastric cancer and laparoscopy-assisted gastrectomy (LAG), due to early detection through mass screening program. We started the LAG in April 2004 and performed 119 cases of gastric cancer in 2005, so we report a surgical outcome compared with that of open gastrectomy (OG). Materials and Methods: 119 patients underwent LAG in 2005, and for open group, 126 patiens of early gastric cancer were selected sequentially from January 2005 to March 2005. We compared clinicopathologic characteristics, postoperative courses and complications between two groups. Results: There was no significant difference between age, a length of hospital stay, distal resection margin and a number of retrived lymph nodes. The operation time was longer in LAG group (239.2 vs 123.3 mins, P<0.001) and a diet progression was faster in LAG group (first flatus: 3.05 vs 3.70 days, SOW: 2.86 vs 3.22 days, liquid diet: 3.87 vs 4.19 days, soft diet: 4.84 vs 5.26 days, P<0.001). But there was no difference statistically in postoperative discharge date (7.73 vs 8.25 days, P=0.229). The additional requirement of analgesic injection was less frequent in LAG group (2.97 vs 4.92 times, P<0.001). The harvested lymph nodes were similar in both groups (23.9 vs 23.1, P=0.563). A complication rate was lower in LAG group (4.9% vs 9.5%), but there was no statistical significance (P=0.179). There was no mortality in both groups and no conversion to open gastrectomy in the LAG group. Conclusion: LAG can be performed safely and accepted in view of curative procedure in treatment of early gastric cancer. But we need the follow up of long-term period to evaluate the survival rate and recurrence, and a prospective randomized controlled study should be done to establish that LAG will be a standard operation for early gastric cancer.

• Sleep Medicine and Psychophysiology
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• v.6 no.1
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• pp.68-75
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• 1999

Objectives: We intended to observe changes in sleep patterns and mood states of night-shift workers following light exposure. We also estimated the degree of tolerance of light exposure. By studying these, we investigated the possibility of applying light therapy to night-shift workers for improving their adaptation. Methods: Twelve night-shift nurses working at Yong-In Mental Hospital volunteered to participate in this study. The study consisted of 3 parts: 1) night-shift control study; 2) light exposure study; 3) day-shift control study. All the nurses accomplished 3 parts of the study, each of which continued for 3 days, except one nurse who did not participate in day-shift control study. During light exposure study, nurses were exposed to bright light for 4 hours from 1AM to 5AM. Sleep patterns were evaluated with wrist actigraphy and automatic sleep analysis program. Mood states and side effects of light exposure were assessed with self-report scales. Results: Sleep period time, total sleep time, and sleep efficiency were increased following light exposure compared with night-shift control study. Light exposure study showed no difference from day-shift control study in above-mentioned sleep parameters. Daily fluctuation of sleep efficiency was less prominent during light exposure study than during night-shift control study. During light exposure study, the subjects felt more elated and energetic in the evening after daytime sleep than during night-shift control study. None of the subjects complained of severe side effects related to light exposure on the third day of light exposure. Tolerance of side effects was noted to develop with the repetition of light exposure. Conclusion: Light exposure improved the daytime sleep of night-shift workers to the level of normal nighttime sleep, making the subjects more elated and energetic. Side effects of light exposure were found to be tolerable. Light exposure seems to be safely applicable to night-shift workers for their adaptation.

• Geotechnical Engineering
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• v.2 no.1
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• pp.27-44
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• 1986

The measured soil data are analyzed to the descriptive statistics and classified into the four models of uncorrelated-normal (UNNO), uncorrelated-nonnormal (VNNN), correlatedonnormal(CONN), and correlated-nonnormal(CONN) . This paper presents the comparisons of reliability index and check points using the advanced first-order second-moment method with respect to the four models as well as BASIC Program. A sin91e-mode Performance function is consisted of the basic design variables of bearing capacity and settlements on shallow foundations and input the above analyzed soil informations. The main conclusions obtained in this study are summarized as follows: 1. In the bearing capacity mode, cohesion and bearing-capacity factors by C-U test are accepted for normal and lognormal distribution, respectively, and negatively low correlated to each other. Since the reliability index of the CONN model is the lowest one of the four model, which could be recommended a reliability.based design, whereas the other model might overestimate the geotechnical conditions. 2. In the case of settlements mode, the virgin compression ratio and preccnsolidation pressure are fitted for normal and lognormal distribution, respectively. Constraining settlements to the lower ones computed by deterministic method, The CONN model is the lowest reliability of the four models.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.3
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• pp.317-324
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• 2008

This study was performed in order to investigate perceptions on environment and environment-friendly agricultural products, knowledge level and opinion about these products. The subjects were 387 college students in Seoul and Incheon area. This survey was conducted by self-administered questionnaire. The statistical analysis was conducted using the SPSS 12.0 program. Male subjects were 53.2% and female subjects were 46.8%. 52.9% of the subjects have knowledge about environment-friendly agricultural products. Also 50.9% of the subjects knew certification label of environment-friendly agricultural products whereas 13.4% knew certification authority of environment-friendly agricultural products. The average scores of 'image of environment-friendly agricultural products', 'attitude towards environment', 'attitude towards agrichemical' were $3.84{\pm}0.68,\;3.51{\pm}0.73\;and\;3.58{\pm}0.87$, respectively. In regard to 'image of environment- friendly agricultural products', the scores were significantly affected by gender (p<0.05), self-recognition of health status (p<0.05) and self-knowledge about environment-friendly agricultural products (p<0.001). In regard to 'attitude towards environment', the scores were significantly affected by self-recognition of health status (p<0.05), self-knowledge about environment-friendly agricultural products (p<0.001), and information about environment friendly agricultural products certificate authority (p<0.01). In regard to 'attitude towards agrichemical', the scores were significantly affected by gender (p<0.001), self-recognition of health status (p<0.05), supplements for health (p<0.05) and self-knowledge about environment-friendly agricultural products (p<0.001). Therefore, various education programs on environment-friendly agricultural products are necessary for college students to make right food choices.

• Journal of dental hygiene science
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• v.11 no.6
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• pp.543-551
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• 2011

Critical thinking is recognized as core competency for dental hygiene practice. The purpose of this study was to investigate relationship between critical thinking disposition and grade, types of educational programs and satisfaction with interpersonal relationship, major, clinical practice. Total 909 students in associate and baccalaureate dental hygiene educational program completed self-reported questionnaire on critical thinking disposition inventory developed by Yoon(2004). The mean score for critical thinking disposition was 3.38~3.39 on a 5 point scale. There was no difference in critical thinking disposition scores between students of associate and baccalaureate programs. There was no difference in critical thinking disposition scores between grade of students. The results showed a statistically significant relationship between critical thinking disposition and satisfaction with interpersonal relationship and major. Multivariate analysis of variance(MANOVA) revealed that all subscales for three groups according to satisfaction with interpersonal relationship were significantly different(Pillai's trace=0.075, F(14,1782)=4.979, p<0.001) and all subscales for three groups according to satisfaction with major were significantly different(Pillai's trace=0.035, F(14,1728)=2.257, p=0.005).

• Journal of dental hygiene science
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• v.10 no.6
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• pp.439-443
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• 2010

The purpose of this study was to prevent excessive use of fluorine toothpaste. To comparatively evaluate the amount used of the fluorine toothpaste in children from 3 to 6 years old, the toothpaste amount was compared according to toothbrush size and toothpaste squeezing method targeting 84 children in 5 child care centers where were located in Hongseong-gun, Chungnam. The toothpaste amount was compared with a method of squeezing to pea-size and a method of smear on toothbrush, targeting 141 students for the Dept. of Dental Hygiene, who are actually carrying out oral health education to targeting children. The statistical analysis was used SPSS 14.0 K for Windows program(Copyright(c) SPSS Inc.). The following results were obtained. 1. The amount of fluorine toothpaste squeezed on toothbrush for children was 0.29 g. The amount of fluorine toothpaste squeezed on toothbrush for adults was 0.34 g. It was surveyed to use the less amount of toothpaste when squeezing to smaller toothbrush (p<0.05). 2. The amount that children aged 3-6 squeezed as the method of squeezing commonly at ordinary times was 0.31g. The amount that was squeezing to pea-size was 0.21 g. The amount that was squeezed by using smear method was measured to be 0.26g. Less amount of fluorine toothpaste was used with the method of squeezing to pea-size and smear method rather than a method of squeezing commonly at ordinary times(p<0.05). 3. As a result of surveying the students of the department of dental hygiene, the amount of having squeezed to pea- size was 0.23 g. It was surveyed to be 0.15 g when having used the smear method. Thus, it was surveyed to use the less amount of toothpaste when using the smear method(p<0.05). 4. Using smaller toothbrush, the amount used of fluorine toothpaste can be reduced. Both smear method and the method of squeezing to pea-size are available for minimizing careless fluorine intake by less used amount of fluorine toothpaste.

• Journal of dental hygiene science
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• v.10 no.6
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• pp.431-438
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• 2010

This study was designed to identify the relationship between emotional labor and reaction factor(job satisfaction, fatigue), buffer factor(social support) among dental hygienist. The number of respondents was 50 who work in dental clinic and period of investigation was march 2010 through April 2010. A structured questionnaire was employed to evaluate the level of participants' sociodemographics, job-related factors, health-related behaviors, emotional labor and self-perceived fatigue, job satisfaction, social support. While the mean values of emotional labor were higher than thosewho work in hospital and lower than those who work in service employees. These results suggest that emotional labor was related to an increase in fatigue and strong correlation between involuntary emotional expression, self-perceived fatigue, job satisfaction, social support in dental hygienist. Multiple regression analysis has found that social support and no. of personnel were main factors that influence to the level of emotional labor in dental hygienist. The results of this study suggest that emotional labor was a determinant predictor of self perceived fatigue. Thus, a management program for emotional labor is strongly recommended for promotion of quality of life in dental hygienist and to improve dental service and competitiveness.