• Journal of the Korea Concrete Institute
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• v.23 no.1
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• pp.13-22
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• 2011

In this study, ultimate strengths of 51 continuous reinforced concrete deep beams were evaluated by the ACI 318M-08's strut-tie model approach implemented with the presented indeterminate strut-tie model and load distribution ratio of the companion paper. The ultimate strengths of the continuous deep beams were also estimated by the shear equations derived based on experimental results, conventional design codes based on experimental and theoretical shear strength models, and current strut-tie model design codes. The validity of the presented strut-tie model and load distribution ratio was examined through the comparison of the strength analysis results classified according to the primary design variables of shear span-to-effective depth ratio, flexural reinforcement ratio, and concrete compressive strength. The present study results of ultimate strengths obtained using the indeterminate strut-tie model and load distribution ratio of the continuous deep beams agree fairly well with those obtained using other approaches. In addition, the present approach reflected the effect of the primary design variables on the ultimate strengths of the continuous deep beams consistently and accurately. Therefore, the present study will help structural designers to conduct rational and practical strut-tie model designs of continuous deep beams.

• Journal of Environmental Policy
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• v.13 no.3
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• pp.109-133
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• 2014

With a growing concern about climate change and green house gases mitigation, carbon labeling policy has been launched in several countries as an environmental policy which connects low carbon production to low carbon consumption. This research aims to propose a model that explains consumers' attitude and brand loyalty toward carbon labeling products. This model specifies the consumer's psychological processes by which consumer values, such as autonomy and environmental values, affect carbon labeling product and corporate images and finally form brand loyalty toward carbon labeling products. Panel data were collected in two separate surveys and analyzed using a structural equation technique. Results are summarized as follows. First, consumers' autonomy value(AV) positively affects locus of control(LC) and corporate image(CI). Second, consumers' environmental value(EV) positively influences perceived consumer effectiveness(PCE), which in turn has a negative effect on perceived barriers(PB). Perceived barriers finally affect product image(PI) negatively. Third, both corporate image and product image have causal relationships with brand loyalty. Our results suggest that carbon labeling policy contributes not only to the reduction of greenhouse gases but also to the increase of consumers' attitude and brand loyalty toward carbon labeling products. This research also provides governments with directions for efficient environmental policy and firms with guidance on effective marketing strategies about carbon labeling.

• Journal of Periodontal and Implant Science
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• v.35 no.4
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• pp.921-937
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• 2005

Mechanical and chemical methods are the two ways to treat the implant surfaces. By using mechanical method, it is difficult to eliminate bacteria and by-products from the rough implant surface and it can also cause the structural change to the implant surface. Therefore, chemical method is widely used in order to preserve and detoxicate the implant surface more effectively. The purpose of this study is to evaluate the effect of tetracylcline- HCl on the change of implant surface microstructure according to application time. Implants with pure titanium machined surface, SLA surface and $TiO_2blasted$ surface were used in this study. Implant surface was rubbed with sponge soaked in 50mg/ml tetracycline - HCl solution for $\frac{1}{2}$ min., 1min., $1\frac{1}{2}$ min., 2 min., and $2\frac{1}{2}min.$ respectively in the test group and with no treatment in the control group. The sponge was soaked in every 30 seconds. Then, the specimens were processed for scanning electron microscopic observation. Based upon the analysis of photographs by three dentists who are not related with this study, the results were obtained as follows; 1. In the pure titanium machined surfaces, the control specimen showed a more or less rough machined surface composed of alternating positive and negative lines corresponding to grooves and ridges. After treatment, machining line was more pronounced for the control specimens. but in general, test specimens were similar to control. 2. In the SLA surfaces, the control specimen showed that the macro roughness was achieved by large-grit sandblasting. Subsequently, the acid-etching process created the micro roughness, which thus was superimposed on the macro roughness. Irrespective of the application time of 50mg/ml tetracycline - HCl solution, in general, test specimens were similar to control. 3. In the $TiO_2blasted$ surfaces, the control specimen showed the rough surface With small pits. The irregularity of the $TiO_2blasted$ surfaces with 50mg/ml tetracycline - HCl solution was lessened and the flattened areas got wider after 1 minute.

• Journal of Korean Society of Forest Science
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• v.108 no.4
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• pp.582-591
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• 2019

This study was conducted to develop low-cost, simplified slope stabilization methods for the continuous utilization of skid trails, and to analyze the effect of the developed methods. Slope stabilization methods were created on the fill slopes of skid trails in the Forest Technology and Management Research Center of the National Institute of Forest Science.We measured the settlement and bearing capacity of skid trail surfaces, and the displacement of slope stabilization methods with respect to the number of passes (maximum 100 passes) by a logging truck weighing 17 tons. The constancy of slope stabilization methods was determined by measuring displacement of the stabilization structure with respect to the number of logging truck passes. Results showed that the bearing capacity in most cases was insufficient, but that the settlement of skid trails was less than 150 mm, which was considered reasonable. In addition, the stability of root staking wallswas somewhat low, but the average displacements of all slope stabilization methods were generally around 20 mm or less, indicating no issues regarding structural stability. By applying the simplified stabilization methods to skid trail maintenance following timber harvesting, efficient timber harvesting can be achieved. Additionally, these methods can be utilized as permanent forest management infrastructures and complement insufficient forest road facilities.

• Culinary science and hospitality research
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• v.19 no.3
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• pp.57-72
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• 2013

This study carried out an empirical analysis on the long-term effects of a marketing communication strategy used as a means of promotion(advertisement, free gift) of Christmas cake despite its high costs. Such verification results were considered to provide as important core elements for successful management in the bakery industry. By utilizing SPSS and AMOS, exploratory factor analysis(EFA) and confirmatory factor analysis(CFA) were conducted for the validity of the measurement items, and Structural Equation Model(SEM) was performed to verify the hypothesis. The analysis result is as follows. First, advertisement attribute(${\beta}$=0.269, t=4.512, p,<0.001) and free gift attitude(${\beta}$=0.293, t=5.043, p<0.001) had a positive influence on trust. Second, trust had a positive influence on purchase intention(${\beta}$=0.513, t=8.677, p<0.001). Third, advertisement attribute(${\beta}$=0.104, t=1.966, p,<0.05) and free gift attitude(${\beta}$=0.204, t=3.817, p<0.001) had a positive influence on purchase intention. Lastly, advertisement attitude appeared different by advertisement types(actors and animation), and ads with an actor were evaluated high than animation ads. Also, gift attitude appeared different by gift types(speaker doll/character hat and turtleneck muffler), and a turtleneck muffler was evaluated high than a speaker doll or a character hat.

• Korean Journal of Social Welfare
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• v.56 no.4
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• pp.215-238
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• 2004

The purpose of this paper is to examine the impact of conflict and nurturing factors for the divorced parent on the behavioral adaptation of their children. The participants in this study include 216 children in divorced families nationwide. Structural Equation Modeling with LISREL8 was used for statistical method. In order to achieve the purpose, researchers firstly tried to test a construct validity of conceptual variables(parental conflict, negative attitude of parental nurturing, child's belief about parental divorce, child's aggression and child's delinquence) by employing exploratory factor analysis(EFA) and confirmatory factor analysis(CFA). Result showed that all the five conceptual variables were discriminated. It was identified as the fit index of path structure was good(CFI=.955, NNFI=.947, RMSEA=.046). The specific result were as follows: 1. the parental conflict(${\xi}1$) was directly related to the negative attitude of parental nurturing(${\eta}1$) and the child's belief about parental divorce(${\eta}2$). 2. the parental conflict(${\xi}1$) was indirectly related to child's belief about parental divorce(${\eta}2$), the child's aggression(${\eta}3$) and delinquence(${\eta}4$). 3. the negative attitude of parental nurturing(${\eta}1$) was directly related to the child's belief about parental divorce(${\eta}2$). 4. the negative attitude of parental nurturing(${\eta}1$) was indirectly related to the child's aggression(${\eta}3$) and delinquence(${\eta}4$). Lastly, and, the child's belief about parental divorce(${\eta}2$) was directly related to the child's aggression(${\eta}3$) and delinquence(${\eta}4$). Researchers also identified the mediating effect of the parental nurturing between parental conflict and child's belief about parental divorce. On the basis of these results, this article provided some suggestions for promoting of children welfare.

• Korean Journal of Social Welfare
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• v.56 no.4
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• pp.239-268
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• 2004

This study examined the role of self-construals in marital satisfaction among men and women, and explored how independent and interdependent self-construals contribute to or undermine marital satisfaction. Data were drawn from a self-administered questionnaire study in which 489 married people(aged 25-75) residing in Seoul participated. Path analyses were conducted using Structural Equation Modeling Program, and a goodness of fit of the proposed path model was evaluated. As expected, the positive impact of independent self-construal on marital satisfaction was mediated by self-esteem and clarity of communication, and that of interdependent self-construal on marital satisfaction was mediated by psychological stability and a sense of relational well-being. The direct effects of these two types of self-construal on marital satisfaction were opposite. As predicted, independent self-construal decreased marital satisfaction, whereas interdependent self-construal increased it. All of the direct and indirect effects of independent and interdependent self-construals on marital satisfaction were statistically significant, except the indirect effect of interdependent self-construal as mediated by psychological stability. The goodness of fit indexes of the path model indicated that the model was acceptable. However, the results of separate path analyses for men and women showed that some of the effects of self-construals on marital satisfaction differed by gender. Based on these results, implications for clinical social work practice were discussed.

• Journal of the Korean Geotechnical Society
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• v.34 no.1
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• pp.37-46
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• 2018

Hollow prestressed concrete filled steel tube (HCFT) piles, which compose hollow PHC piles inside thin wall steel tubes, are developed. In order to investigate the strength characteristics of HCFT piles, flexural and shear tests were conducted on HCFT piles as well as PHC and steel pipe piles with the same diameter. Results of the test program showed that the flexural strength of HCFT piles was 2.88 and 1.19 times those of ICP and steel pipe piles with thickness of 12 mm, respectively, and its shear strength was 2.40 times that of steel pipe piles. The shear key attached to the inside of thin wall steel tube did not affect the flexural behavior of HCFT piles. It was also observed that the flexural strengths of HCFT piles with diameters of 450 and 500 mm were 35 to 63% higher than the sum of the flexural strengths of its components, respectively, because the strength of concrete in compressive zone increased by confining effect of thin wall steel tube on concrete. HCFT piles used as upper piles in hybrid composite piles might decrease the lateral displacement and increase the structural safety of structures subjected to lateral loads.

• Journal of Korean Home Economics Education Association
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• v.31 no.3
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• pp.41-55
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• 2019

The present study examined the direct effects of parental support and monitoring on multicultural adolescents' school adjustment and the mediating role of ego-resilience in the relationships, under the condition of controlling foreign mothers' Korean language abilities. We used data from 1,325 1^st grade middle school students from multicultural families, who participated in the Multicultural Adolescent Panel Survey(MAPS) administered by the National Youth Policy Institute(NYPI). Structural equation modeling analysis revealed the following: parental support and monitoring directly and positively related with multicultural adolescents' school adjustment, and the direct effect of parental support on the school adjustment of multicultural adolescents was greater than that of parental monitoring. In addition, the adolescents' ego-resilience partially mediated the relationships between parental support and monitoring, and their school adjustment. Finally, we recommended the roles of parent education and home economics education in supporting school adjustment and elevating ego-resilience in multicultural adolescents.

• Journal of the Korea Institute of Building Construction
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• v.20 no.1
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• pp.43-51
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• 2020

The main purpose of protective facility for small military unit is to provide the protection of not all the weapons system but the near-miss bullet in Korean army. In particular about the small caliber bullets, especially KM80 in Korea, there were many studies that both of the experiential and structural design methods dose not reflect enough the military threat. For that reason, a new equation to calculate effective anti-piercing depths for RC slabs against small caliber bullets is proposed in earlier research with actual shooting test. But, the test only considers the strength of concrete without the thickness of concrete, types of aggregate, the angle of yaw of bullet, high-strength concrete, etc. Therefore, this study evaluated the ballistic resistance performance by thickness and proportion of magnetic aggregate of concrete. As a result, we identified two major statistical estimations that the error of piercing depth by the angle of yaw of bullet could be cancelled by barrage and the thickness and proportion of magnetic aggregate of concrete dose not effect on the protection ability of concrete structure.