• Solar Energy
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• v.8 no.1
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• pp.74-81
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• 1988

A preliminary study has been done to investigate the thermal performance of an indirect system. Direct systems are also analyzed and the results are compared with those of the indirect system where possible. Values from the numerical simulation show very good agreement with the measured data. Although the indirect system is generally expensive and not as efficient as direct systems, it is more reliable in frigid weather conditions like the winters in Korea.

• Proceedings of the Korea Database Society Conference
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• 2010.06a
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• pp.235-247
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• 2010

Introduction of ICE(Integrated Collaboration Environment) has a great effect on corporate performance. In particular, it is expected that information sharing and collaboration among transaction partners will be an important factor which mediates ICE and its performance. Under such a background, this research intends to identify the influence of ICE by manufacturing industry on corporate performance through role of the parameter of information sharing and collaboration. The result of this research may be summed up as follows: ICE promotes information sharing and collaboration among enterprises, it accelerates integration of supply chain network among enterprises and cooperation. In particular, ICE has a great effect on information sharing. And information sharing has a direct effect on collaboration and performance. However, when we classify corporate performance into the "performance due to introduction", which is direct performance, and the "overall performance", which is indirect performance, the result of this research is as follows: information sharing has a great effect on the performance due to introduction, but does not have a meaningful effect on indirect performance. On the other hand, collaboration does not have any effect on the performance due to introduction, but has a meaningful effect on the overall performance, which is indirect performance. It is necessary to study and analyze additional this result in future.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.11
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• pp.1555-1561
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• 2018

Tracking and detecting targets by the millimeter wave seeker is affected by movement of platform. Stabilization equipments use an inertial sensor to compensate for disturbance of stabilizing gimbal or platform. In the direct line of sight stabilization system, an inertial sensor is mounted on inner gimbal to compensate the disturbance directly, so the performance is excellent and the implementation method is simple. However gimbal design requires somewhat larger volume. Since an inertial sensor is mounted on gimbal base in the indirect line of sight stabilization system, additional space of gimbal is not required for the gimbal design. However, this method does not directly compensate for the disturbance of the line of sight stabilization axis, which can degrade performance. In order to perform the tracking performance, two methods are analyzed for line of sight stabilization performance based on direct and indirect of a 2-axis gimbaled servo system for millimeter wave seeker in this study. The simulation and experimental results validate the performance comparison of two methods.

• Journal of the Korea Safety Management & Science
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• v.12 no.2
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• pp.55-64
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• 2010

This study tried to focus on nontraditional job that has not been studied in terms of the subjects associated with MSDs(Musculoskeletal Disorders). Specifically, dental procedure was the job to be analyzed in this study. An alternative method as well as a traditional method for viewing teeth while performing simulated dental procedures. Four graduated students did both methods(direct view and indirect view) as the subjects in this study. The method based on indirect view used a video camera and monitor to view the teeth. The experiment was conducted five times for each subject. The major findings in this study were as follows; 1) Job speed was increased with the repetitions for both methods, 2) Difference of Neck flexion between direct and indirect methods was statistically siginificant(Neck flexion for indirect method was dramatically decreased), 3) Difference of job speed between direct and indirect methods was statistically significant(Job speed for direct method was faster than that of indirect method), 4) Difference of error rate between direct and indirect methods was statistically significant(error rate for direct method was lower than that of indirect method), 5) Even though indirect method did not provide better performance in terms of job speed and error rate yet, it seemed to need a trade-off between two methods in the future since indirect method provided better working postures than that of direct method.

• Journal of Families and Better Life
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• v.28 no.6
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• pp.95-111
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• 2010

The purposes of this study were to show general trends in the aspects of psychological family environment (parental communication), peer factor, academic performance factor, depression perceived by adolescents and to examine possible changes in such trends in accordance with demographic variables and the family structure environment (parental marital status, family economic status, and parents' education level), and then to determine the effect of these variables on adolescents' depression. The subjects were 1009 middle and high school students in Seoul and Gyeonggi province. The main results were as follows: 1) Paternal communication was significantly lower in technical high school students, divorced/ separated parents, and families of lower economic status. Maternal communication was significantly lower in male students, divorced/sepa-rated parents, and families of lower economic status. Academic performance problems was significantly higher in males, technical high school students, divorced/ separated parents, families of lower economic status, and a less educated father. Peer relations was significantly lower in students of divorced / separated parents, and of families of lower economic status. Depression was significantly higher in technical high school students, divorced / separated parents, and families of lower economic status. 2) In the case of male students, paternal communication had both a direct and an indirect negative effect through peer relations on depression, while academic performance problems had both a direct and an indirect positive effect through peer relations on depression. Both peer relations and maternal communication had a positive and a negative direct effect on depression. School grade had both a direct and an indirect negative effect through paternal communication on depression. Parental marital status(divorced or separated) had both a direct and an indirect positive effect through academic performance problems on depression. Family economic status had only an indirect effect on discussed.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.337-340
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• 1997

In this paper we propose direct and indirect adaptive controllers for a nonlinear multivariable steam generating unit(200MW). In the direct adaptive scheme the estimation of the controller parameter are achieved from tracking error, while in the indirect approach the unknown parameter of the boiler system is estimated by the Hopfield network-based identifier. The performance of two proposed adaptive controllers is shown through simulations.

• Proceedings of the KIEE Conference
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• 2001.07d
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• pp.2246-2248
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• 2001

This paper presents a new vector control scheme for induction motor. An exact knowledge of the rotor flux position is essential for a high-performance vector control. The position of the rotor flux is measured in the direct schemes and estimated in the indirect schemes. Since the estimation of the flux position requires a priori knowledge of the induction motor parameters, the indirect schemes are machine parameter dependent. The rotor and stator resistance among the parameters change with temperature. Variations in the parameters of induction machine cause deterioration of both the steady state and dynamic operation of the induction motor drive. Several methods have presented to minimize the consequences of parameter sensitivity in indirect scheme. In this paper, new estimation scheme of rotor flux position is presented to eliminate sensitivity due to variation in the resistance. The simulation is executed to verify the proposed vector control performance and to compare its performance with that of indirect and direct vector control.

• Journal of Korean Society on Water Environment
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• v.26 no.6
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• pp.963-968
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• 2010

This study has carried out to evaluate the performance of direct and indirect oxidation electrode for the purpose of decolorization of Rhodamine B (RhB) in water. Four kinds of electrodes were used for comparison: Pt and JP202 (indirect oxidation electrode), Pb and boron doping diamond (BDD, direct oxidation electrode). The effect of applied current (0.5 ~ 2.5 A), electrolyte type (NaCl, KCl, HCl, $Na_2SO_4$ and $H_2SO_4$) and electrolyte concentration (0.5 ~ 2.5 g/L), solution pH (3 ~ 11) and initial RhB concentration (25 ~ 125 mg/L) were evaluated. Experimental results showed that RhB removal efficiency were increased with increase of current, NaCl dosage and decrease of the pH. However, the effect of operating parameter on the RhB removal were different with the electrode type. JP202 electrode was the best electrode from the point of view of performance and energy consumption. The order of removed RhB concentration per energy lie in: JP202>Pt>Pb>BDD.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.11
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• pp.269-280
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• 2020

This research aims to determine the direct and indirect effects of digital literacy, economic literacy, and entrepreneurial skills on the performance of small- and medium-sized enterprises (SMEs) in garment clusters in the Bulak tourism industry Depok. Carrying out quantitative research with survey methods, data collection is using a questionnaire technique with 90 respondents, via saturation sampling. This research data analysis uses SPSS software version 25.0. Path analysis is used to determine the direct and indirect effects between variables. The results showed digital literacy, economic literacy, and entrepreneurial skills significantly and positively affect the performance of small- and medium-sized enterprises. The main finding in this study is that digital literacy has the greatest influence on the performance of SME entrepreneurs, both directly and indirectly. The results of the study provide input on performance development strategies for SME entrepreneurs through digital literacy, including digital business relationships, online facilities, and networks. The findings are also complementary to the factors shaping the performance of SME entrepreneurs in the digital age. The research results show that digital literacy has the greatest direct and indirect influence on the performance of SME entrepreneurs; this shows the essential contribution of digital literacy in developing business and marketing networks.

• Journal of the Korean Society of Costume
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• v.51 no.8
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• pp.77-91
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• 2001

The purpose of this study was to investigate the effects of the perceived facial attractiveness and appropriateness of clothing on the evaluation of task performance of target person mediated by subjects'likability toward and trait evaluation of the target person. The facial attractiveness of the female university students were used as index of physical attractiveness in this study. Three levels of facial attractiveness was manipulated based on the judgements by 30 female university students. Four types of clothes were selected perceived appropriate for two assumed situations by female university students. Three female faces having high. medium, and low attractiveness were simulated with the same body dressed four types of clothing respectively using CAD system, and a total of 12 stimulus persons were created. The design for the experiment was a $3\tiems4\times2$ randomaized factorial. with three levels of facial attractiveness(high, medium, low), and four types attire(formal-masculine, formal-feminine, casual-masculine, casual-feminine), two kinds of context (job interview, dating) in which perceptions were occurred. The subjects of this study was 524 male and female(262 of male, 262 of female) university students from 3 universities in Kwangju, Korea. The data were analysed using factor analysis. descriptive statistics, regression, path analysis. The results were as follows : 1. In bogus job interview. the direct effect of perceived facial attractiveness on task performance evaluation was .175 and the indirect effect mediated by likability and trait evaluation was .285 in path analysis model. The direct effect of perceived appropriateness of clothing on task performance evaluation was .111 and the indirect effect mediated by likability only was .0564 in pass analysis model. 2. In dating situation, the direct effect of perceived facial attractiveness on task performance evaluation was .355, the indirect effect mediated by likability and trait evaluation was .188 in path analysis model. The direct effect of perceived appropriateness of clothing on task performance evaluation was .108, the indirect effect mediated by likability and trait evaluation was .060 in Pass analysis.