• The Journal of the Korean dental association
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• v.47 no.7
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• pp.435-443
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• 2009

The purpose of this study was to compare the centering ratio and reduction of canal curvature according to the preparation sizes of #30, #40 and #50 using three rotary NiTi instruments which have different shaft tapers. Seventy-two simulated root canals in clear resin blocks (Endo Training Bloc; Dentsply Maillefer, Ballaigues, Switzerland) were divided as following 3 groups according to the file system; the 24 canal blocks prepared with each of ProTaper Universal system (Group P), LightSpeed eXtra system (Group L), and K3 (Group K). The pre- and post-instrumented root canals were scanned and superimposed to evaluate and calculate the centering ratio and reduction of canal curvature. Mean scores of each group were statistically analyzed using one-way ANOV A and Duncan's multiple range test for post-hoc comparison. The results were as followings: 1. Group L showed better centering ratio, followed by K and P. And all experimental groups generally showed increasing tendency of centering ratio as the apical size was increasing from #30 to #50, except at 1 mm level of group P where showed reducing tendency of centering ratio. The smaller the ratio, the better the instrument remained centered in the canal. 2. Group P showed more decrease of canal curvature at all apical shaping size (p < 0.05). Under the conditions of this study, the shaft design could affect the quality of canal shaping and the smooth taperless flexible (LightSpeed) shaft design was capable of preparing canals with good morphological characteristics in curved canals.

• Restorative Dentistry and Endodontics
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• v.32 no.4
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• pp.385-396
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• 2007

The aims of this study were to compare the shaping effect and safety between single length technique recommended by manufacturer and crown-down technique using Mtwo rotary file and to present a modified method in use of Mtwo file. Sixty simulated root canal resin blocks were used. The canals were divided into three groups according to instrument and the manner of using methods. Each group had 20 specimens. Group MT was instrumented with single length technique of Mtwo, group MC was instrumented with crown-down technique of Mtwo and group PT was instrumented with crown-down technique of ProTaper. All of the rotary files used in this study were operated by an electric motor. The scanned canal images of before and after preparation were superimposed. These superimposed images were evaluated at apical 1 to 8 mm levels Angle changes were calculated. The preparation time, weight loss, instrument failure and binding, canal aberrations, and centering ratio were measured. Statistical analysis of the three experimental groups was performed with ANOVA and Duncan's multiple range tests for post-hoc comparison and Fisher's exact test was done for the frequency comparison. In total preparation time, group MT and group MC were less than group PT. In the aberrations, group MT had more elbows than those of group MC and group PT. The binding of group MC was least and group MT was less than group PT (P < 0.05). Under the condition of this study, crown-down technique using Mtwo rotary file is better and safer method than single length technique recommended by the manufacturer.

• Fashion & Textile Research Journal
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• v.12 no.6
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• pp.745-754
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• 2010

This study is to find return factors when modern consumers purchase goods from an internet shopping mall and then to analyze the characteristics of complaints act and information search behavior. Subjects of research are 245 men and women, who have experience with more than one return in internet fashion shopping mall, in their twenties. The data were analyzed by using Factor analysis, Cronbach's analysis, one-way ANOVA, Duncan test as a post identification, Pearson's correlation analysis and multiple regression analysis. The results of this study are that male and female consumers in their 20s are mainly aware of the return factors: impulse buying, product status, deliver service, service after purchase, hype and comfortableness. And complains behavior often conduct public action, private action, nonaction. Information search behaviors for risk reduction when they purchase are product comparison, oral information search, neutral marketing information search, and service information search. The return factor from the internet fashion shopping had the greatest impact on public action and deliver services factor was a big complaint. In addition, impulse buying & Hype affect private action and non-action is influenced by impulse purchase. The consumer types by the return factors in internet fashion shopping mall are classified into the return group by deliver service, the return group by complex factors, and the return group by product status. Furthermore, there are significant differences in complaining behavior among these groups. In the information search behavior for reduction of risk factors, the return group by complex factors did more active information search behavior than the other groups. The return group by deliver service searched oral information and the return group by product status explored the neutral marketing information.

• Restorative Dentistry and Endodontics
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• v.35 no.2
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• pp.69-79
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• 2010

The purpose of this study was to evaluate the effect of film thickness of various resin cements on bonding efficiency in indirect composite restoration by measurement of microtensile bond strength, polymerization shrinkage, flexural strength and modulus, fractographic FE-SEM analysis. Experimental groups were divided according to film thickness (< $50\;{\mu}m$-control, $50\;{\mu}m$-T50, $100\;{\mu}m$-T100, $150\;{\mu}m$-T150) using composite- based resin cements (Variolink II, Duo-Link) and adhesive-based resin cements (Panavia F, Rely X Unicem). The data was analyzed using ANOVA and Duncan's multiple comparison test (p < 0.05). The results were as follows ; 1. Variolink II showed higher microtensile bond strength than that of adhesive-based resin cements in all film thickness (p < 0.05) but Duo-Link did not show significant difference except control group (p > 0.05). 2. Microtensile bond strength of composite-based resin cements were decreased significantly according to increasing film thickness (p < 0.05) but adhesive-based resin cements did not show significant difference among film thickness (p > 0.05). 3. Panavia F showed significantly lower polymerization shrinkage than other resin cements (p < 0.05). 4. Composite-based resin cements showed significantly higher flexural strength and modulus than adhesive-based resin cements (p < 0.05). 5. FE-SEM examination showed uniform adhesive layer and well developed resin tags in composite-based resin cements but unclear adhesive layer and poorly developed resin tags in adhesive-based resin cements. In debonded surface examination, composite-based resin cements showed mixed failures but adhesive-based resin cements showed adhesive failures.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.4
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• pp.382-390
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• 1999

In order to identify the responses of Korean soybean cultivars to sudden death syndrome (SDS), forty-two Korean cultivars and three check cultivars (Hartwig and PI 520733 are resistant; Hartz 6686 is susceptible) were tested with sorghum seed inoculum infested with Fusarium solani f. sp. glycines isolate 171 in the greenhouse. This isolate has blue pigment cultural shape on potato dextrose agar (PDA) medium. All Korean cultivars inoculated with F. solani isolate 171 showed the typical SDS symptoms and disease severity on soybean leaves in each cultivar varied at 4 weeks after inoculation. Nine cultivars were included in the most SDS susceptible group and six cultivars were included in the most susceptible group based on Duncan＇s multiple range tests (P$\leq$0.05). In results of the LSD analysis for SDS the resistant group, a total of twenty-five Korean cultivars were included in the same SDS resistant group as PI 520733 or Hartwig and fourteen Korean cultivars were included in the same SDS susceptible group as Hartz 6686. In the second experiment, ten Korean cultivars, ten U.S. cultivars, and one introduced line were compared in the same way as the first experiment Disease severity ranking of check cultivars, Hartwig, PI 520733, and Hartz 6686, were the same as in the first experiment. Within Korean cultivars, seven cultivars showed the consistent severity proportions of leaf symptoms. Disease rankings of these cultivars in this experiment were the same as those in the first experiment. Three US cultivars: Hartwig, Hartz 5454, and Forrest, three Korean cultivars： Keunolkong, Myeongjunamulkong, and Jinpumkong 2, and one introduced line, PI 520733, were included in the highest SDS resistant group. Shinphaldalkong 2, Milyang 87, and Samnamkong consistently showed the highest SDS susceptibility in both experiments. Average disease severity in the first and the second experiment were 49.56% and 45.39%, respectively.

• Journal of Korean Society of Forest Science
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• v.102 no.4
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• pp.515-521
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• 2013

The objective of this study was to estimate the changes of stand structure before and after applying the three different silvicultural treatments such as selection cutting system, two-storied system, and shelterwood system. This study has been conducted in the natural deciduous forests in Pyeongchang of Gangwon Province, Korea. Nine permanent sampling plots of 0.09 ha were established in the forests and each of the three silvicultural treatments was applied to three sampling points. Some tree variables were measured in each stand before and after the silvicultural treatments were applied. With these data, stand attributes were estimated in each stand before and after applying the silvicultural treatments. In this study, a competition index was used to analyze the differences among structures of stands managed by three different silvicultural treatments. Hegyi's distance-dependent competition index was estimated and compared to analyze the differences of stand structures among the stands before and after silvicultural treatments. A method using a height angle $50^{\circ}$ from the base of the subject tree was adopted as the selection method of competitor trees. Duncan's multiple range test and t-test were then employed to statistically analyze the difference of stand structure among the stands. The results revealed that competition status among trees in the stand seems to be improved after applying the silvicultural treatments. There are significant differences in the competition index between before and after silvicultural treatments for each stand. According to the evaluation of competition index, it was confirmed that spatial structure of the stands was improved by applying the silvicultural treatments.

• Korean Journal of Health Education and Promotion
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• v.23 no.2
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• pp.77-89
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• 2006

Objectives: Recent studies have shown that tailoring to women's individual beliefs and stage of cancer screening adoption increase the probability that cancer screening will ensue. To identify variables associated with cancer screening behavior, many studies for cancer screening have used the Transtheoretical Model(TTM). This study was carried out to identity the cognitive and behavioral factors associated with breast cancer screening by stages of change among women, forties aged. Methods: Building on the TTM constructs, we collected the data to test the association with cognitive and behavioral factors for breast cancer screening by stage of change among women, forties aged (N=232), using the self-reported questionnaire. The stages of change were grouped according to screening participation and intention for breast cancer as precontemplation, contemplation, preparation, action, and maintenance. We found out the association between breast cancer screening and cognitive and behavioral factors, and testified the difference between stages of change by chi-square test, one-way ANOVA, and multiple comparison analysis(Duncan test). Results: Analyses of 232 women showed that participation on mammography was 68.1% within lifetime and 46.1% within last 2 years, and we found out the association with breast cancer screening participation, intention and cognitive-behavioral factors. The stages of change based on participation and intention were different from the decisional balance, the screening attitude, and the self-efficacy(p<0.01). The decisional balance was differ from stages of change because the difference on opinions about pros(positives) and cons(negative) were likely to significant by stages of change(p<0.05, p<0.01). Conclusion: To increase the screening rate for breast cancer, it should be developed the tailored message and recommend guideline. And the tailored message should be designed to increase the pros of breast cancer screening(mammography) and to decrease the cons, and considered the woman's stage of adoption.

• Journal of the Korean Home Economics Association
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• v.30 no.2
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• pp.73-80
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• 1992

This study was attempted to investigate the prevalence of anemia and to obtain nutritional education data for high school girls by analyzing the factors influencing on anemia. Total fo 113 subjects(21 female high school students in Seoul and 92 female students in Inchon) were participated in this study from July 1 to July 15, 1990. Hb and Hct values were measured to evaluate the iron status. Duncan's multiple range test were performed for the comparison between the mean values of the various group. Correlations among various factors were analyzed by Pearson's correlation coefficient. The results of this study are summarized as follows. 1. The maen Hb and Hct values were 13.2g/dl and 41.3%. The rate of anemia of the subjects was 5.3% by the criteria of Hb concentration and 2.7% by the Hct value according to World Health Organization. 2. Subjects who had an early menarche had significantly higher weight and triceps than the ones ofr the girls with a late menarche. 3. There were positive relationships among Hb and Hct values, ages of memarche and cycle of menstruation. Hb, Hct values were significantly higher in the subjects who had frequent bed time snack, high intakes of meats and fishes group and vitamin A, and low calcium intake. In conculsion, the prevalence of anemia of the subjects was much lower than the previous years. There were positive relationships among Hb and Hct values, age of menarche, night snack, and intakes of meats and fishes and fruits. Therefore, it could be concluded that nutrition education should be emphasized for the high school girls to improve the quality of diet and prevent anemia.

• The Korean Journal of Rehabilitation Nursing
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• v.3 no.2
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• pp.127-140
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• 2000

The purpose of this study is to identify the effect of sexual rehabilitation education on the knowledge and adjustment of sexual of spinal cord injury clients by the method of nonequivalant control group pretest-posttest group. The data were collected from Jan. 19 though Feb. 16, 2000. The experimental group was 26 spinal cord injury client from one rehabilitation center, and the control group was 26 spinal cord injury client from two rehabilitation center. Sexual rehabilitation education was done with manuals, videotapes and chart. Education time was 120 minutes a week for 2 weeks. The study tool was about Sexual Knowledge, designed Song, Chung Sook(1990) and SIAC(Sexual, Interest, Activity, & Satisfaction) designed Kruter, Sullivan, Siosteen(1994) translated by Kang, Hyun Sook, Koh, Jung Eun, Suh, Yeon Ok, Yee, Oon Hee(1999). The collected data were analyzed SPSS program. The Data were analyzed descriptive statistics and $X^2$ test, Pearson's Correlation Coefficient, t-test, F-test (ANOVA), Duncan's multiple comparison test. The result were as follows. 1. The first hypothesis was accepted : The group educated about sexual rehabilitation has more sexual knowledge than those of the uneducated group(t = 7.412, p = .001). 2. The second hypothesis was accepted : The group educated about the sexual rehabilitation has more adjustment of sexual than those of the uneducated group(t = 5.524, p= .001). 3. The third hypothesis was accepted: The higher sexual knowledge state, the higher sexual adjustment(r= .449, p= .003). According to results, sexual rehabilitation education helps Spinal cord Injury Clients to gain knowledge and adjustment of sexual.

• Korean Journal of Occupational Health Nursing
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• v.14 no.1
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• pp.24-33
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• 2005

Purpose: This cross-sectional study was to find out smoking condition, smoking related knowledge and attitudes of white color workers to provide baseline data which were to develope smoking cessation programs. Methods: The subjects were 303 workers in G-city. Data were collected from July 1st to Aug. 31st 2003 by self-reported questionnaire. Data were analyzed by descriptive statistics, t-test, ANOVA, and Duncan's multiple comparison test, using SAS-pc 8.0 version. Results: Average age of the laborers was 32.3 years, and 50.7% of male were smoking currently, and 2.4% of female were so. Starting age of smokers was average 20.1 and smoking period was average 12.4 years. Majority of smokers smoked more than one pack of cigarettes in a day. Average points of nicotine dependency was 3.9 out of 10 and 12.5% were more than 7. Those who wanted to 'quit smoking very soon' and 'decided to quit smoking right now' were 29.1%. But those who got any helps and advices from professional experts in smoking cessation were 6.4%. 83.5% of the smokers had tried to quit smoking but failed due to their stress(44.6%), lack of will(36.6%) etc. Laborers knowledge related smoking score were average 11points out of 15, and attitudes were average 75.7points out of 125. Smokers showed significantly low knowledge(p=.012), and more allowing attitudes(p=.001). Conclusions: The smoking cessation programs for the workers should consist of stress management skills, and strengthened willingness. And should be run the program for those who want to 'quit smoking very soon' and 'decided to quit smoking right now' first of all.