• The Journal of the Korean dental association
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• v.50 no.7
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• pp.368-376
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• 2012

The demand for tooth-colored restorations has grown considerably during the last decade. Posterior composite restorations have risen in popularity as a result of the development of improved resin composites, bonding systems and operating techniques. A major limitation of direct composite restoration is the difficulty of controlling the polymerization shrinkage. To overcome this limitation, the indirect fabrication of a composite restoration and cementation with resin cement has been advocated. Unfortunately, the current available resin cements with indirect restorations do not always bond to dentin as strongly as dentin adhesive systems bond with direct resin composite restorations. Several procedural strategies have been proposed for indirect composite restoration. In this regard, the rationale for the indication, characteristics and clinical application is described in this paper. As a result, we will try to suggest the evidence-based guidelines for indirect composite restorations by reviewing each available indirect composite products, technical procedure and pronosis.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.05a
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• pp.333-336
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• 2012

In modern Construction Industry, as accumulation of capital and improvement of technology skills, buildings are becoming higher and more enormous, also the portion of steel works has been increasing. In addition, it is necessary to predict the optimum level of construction cost in a reasonable way. The composition of construction is direct construction cost, indirect construction cost and so on. However, it is not enough to study about indirect construction cost rather than direct construction cost. In this study, the state of productivity and indirect construction cost are analyzed in the steel production. As a result, the productivity and ratio of indirect cost in steel plant by inserted per 1ton are suggested.

• Journal of the Korean Home Economics Association
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• v.41 no.1
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• pp.77-91
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• 2003

The purpose of this study was to explore the effects of children's perception of communications with mothers and self-control on game addiction. The subjects were 739 children of 4th, 5th and 6th grade. The subjects rated themselves on questionnaires regarding communications with mothers, self-control and game addiction scale. The major findings of this study were as follows: 1) 6th grade children addicted more than 4th and 5th grade children. And boys addicted more than girls. 2) Sex had a direct and indirect effect through children's perception of problematic communications with mothers and self-control on game addiction and was the first contribution factor Children's self-control had a first direct negative effect on game addiction. 3) Children's perception of problematic communications with mothers had a direct positive effect and an indirect positive effect through self-control on game addiction. Grade had a direct positive effect and an indirect positive effect through children's perception of open and problematic communications with mothers and self-control on game addiction. Children's perception of open communications with mothers had a direct positive effect and an indirect negative effect through self-control on game addiction.

• Journal of the Korean Home Economics Association
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• v.48 no.7
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• pp.33-48
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• 2010

The purpose of this study was to explore the effects of family structure(parentral marital status and socioeconomic status), parental communication, academic problems, and peer relationship on juvenile delinquency. The participants were 1009 middle school and high school students in Seoul city and Gyeonggi Province. The major results were as follows: 1) Parental marital status(divorced/seperated) had both direct and indirect positive effects and lower class in socioeconomic status had an indirect positive effect on academic problems and peer relationship on juvenile delinquency rates. 2) Open maternal communication had a direct negative effect on juvenile delinquency rates. However, open paternal communication had both direct and indirect negative effects. 3) Academic problems had both direct and indirect positive effects on juvenile delinquency rates. 4) Peer relationship had a direct positive effect on juvenile delinquency rates. 5) The level of effects that each variable had differed by delinquency types. Based on these results, implications for preventing juvenile delinquency were discussed.

• Journal of Integrative Natural Science
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• v.9 no.1
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• pp.67-71
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• 2016

The university president direct election system in Korea had begun in 1987 as a movement of college democratization in the 1980s after 6.29 Declaration. Since then, many national/private universities had adopted the election system. However, it has posed many problems and it caused a sharp division of opinions between those who approve and disapprove the direct election system. Since 2005, the government has made official of the reformation and/or abolition of the university president direct election system, and has kept pushing for universities to give up the direct election system. Now, only 3 or 4 universities hold on to the system, and many universities have changed into the indirect election system. In the indirect election, a key is the composition of president nomination committee, which confirms the university members's variety. Many universities adopting the indirect election system have used simple random sampling, like drawing lots, to compose the president nomination committee. However, drawing lots has a problem that it has large possibility of composing a biased committee. This research suggests systematic sampling as an alternative to drawing lots. A numerical analysis was conducted using a data of a university in which the indirect election was implemented recently. The drawing lots gave the biased nomination committee. On the other hand, the systematic sample improves the problem and confirms more the variety of all members.

• Archives of Plastic Surgery
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• v.35 no.1
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• pp.48-55
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• 2008

Purpose: We measured linear distances, angles and inclinations on the cast models of the noses, and compared these indirect measurements with the direct measurements obtained from the nose in order to validate the accuracy of the indirect anthropometry using the cast model. Methods: Subjects were 50 males and 50 females, medical students in twenties(mean 27.1 years). Cast models were made from the alginate impression material and the plaster. In direct anthropometry, 16 linear, 7 angular, and 2 inclination measurements between 11 landmarks on the nose were obtained using sliding caliper, spreading caliper, and fabric tape measure. At the same time, the same measurements were obtained from the cast models of the same people. Total 25 measurements were compared, and tested by the independent t-test of SPSS. Results: The standard values of Korean nose in twenties were obtained. 24 measurements except the columellar labial angle were not statistically different between the indirect anthropometry and the direct anthropometry. Conclusion: Indirect anthropometry on the cast model of the nose revealed no significant difference from the anthropometric measurement statistically, accounting for 24 in 25 measurements(96%). There are two possible reasons that caused the difference of columellar labial angle between direct and indirect anthropometry. First, the columellar labial angle could be decreased by protrusion of the lips which resulted from contracting mouth in which an drinking straw had been applied on the mouth corner for patients' respiration during making cast model. Second, it is generally known that the columellar labial angle could be measured larger when soft tissues were pressed by protractor in direct anthropometry. Using a drinking straw with greater diameter, and scheming respiration through the nostrils that patients don't feel discomfort, the more accurate data would be obtained from the indirect anthropometry using the cast models of the noses.

• Archives of Plastic Surgery
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• v.34 no.1
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• pp.18-23
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• 2007

Purpose: Anthropometry can be divided into two methods, direct anthropometry and indirect anthropometry. The most ideal and accurate method is a direct anthropometry. However, it is difficult to measure in the case of children because of poor cooperation, and it lacks re-productivity. Cast model has advantages of three dimensional featuring, inexpensive and easy fabrication. This study is conducted to find out an accuracy of indirect anthropometry on cast model by comparing it with direct anthropometry. Methods: Total 48 cleft lip nasal deformity patients (unilateral, 40; bilateral, 8) were included in this study. Cast models were made before surgery under general anesthesia with alginate impression material and model plaster. Eleven linear measurements among 7 landmarks were taken as direct anthropometry before surgery with Castroviejo spreading caliper. At the same time, indirect anthropometry on cast model was done at the same linear distances as well. Results: Of the total 11 linear measurements, both ala lengths, both columella lengths, nose width, projective distance between facial insertion points of the ala, projective distance between the alar base points, right nostril floor width, and columella width were statistically correlated between indirect anthropometry on cast model and direct anthropometry. However, the nasal tip protrusion and the left nostril floor width were not statistically correlated. Conclusion: Accuracy of indirect anthropometry on cast model can be influenced by cast model fabrication techniques and correct identification of landmarks. Nasal tip protrusion could be reduced by compression of the nasal tip in the process of cast model fabrication and nostril floor width can be varied by muscle relaxation of anesthetics and incorrect identification of subalare in cleft lip nasal deformity. If sufficient care is taken to make cast model and to define landmarks exactly, indirect anthropometry on cast model can be a reliable method as direct anthropometry.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2008.10a
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• pp.38-41
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• 2008

To investigate the evolution of microstructure and texture in AZ31 Mg alloy, direct/indirect extrusion process was carried out at $300^{\circ}C$ with various extrusion speeds. The distribution of grain size depends on extrusion method and extrusion speed. More homogeneous grain site can be obtained at higher extrusion speed of indirect extrusion process. Extrusion speed does not affect significantly texture evolution during extrusion process regardless of extrusion method. ODF section is more useful to understand texture evolution during extrusion process compared with pole figure.

• International Journal of Control, Automation, and Systems
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• v.4 no.2
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• pp.146-154
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• 2006

In this paper, we propose direct and indirect adaptive fuzzy sliding mode control approaches for a class of nonaffine nonlinear systems. In the direct case, we use the implicit function theory to prove the existence of an ideal implicit feedback linearization controller, and hence approximate it to attain the desired performances. In the indirect case, we exploit the linear structure of a Takagi-Sugeno fuzzy system with constant conclusion to establish an affine-in-control model, and therefore design an indirect adaptive fuzzy controller. In both cases, the adaptation laws of the adjustable parameters are deduced from the stability analysis, in the sense of Lyapunov, to get a more accurate approximation level. In addition to their robustness, the design of the proposed approaches does not require the upper bounds of both external disturbances and approximation errors. To show the efficiency of the proposed controllers, a simulation example is presented.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.216-216
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• 2011

There have been various direct or indirect methods to measure the characteristics of plasma. Comparing to direct method like Langmuir probe method, indirect measurements which give information as some external parameters like current, voltage, or phase are easier to obtain. In this research, an indirect method to measure averaged plasma density in a transformer coupled plasma(TCP) has been proposed and evaluated. With a simple analytic model connecting electrical characteristics to plasma impedance, direct measurement via double Langmuir probe has been performed. This result may play a meaningful role to diagnose TCP or similar plasma sources