• Journal of Families and Better Life
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• v.29 no.3
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• pp.99-118
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• 2011

The purpose of this study was to investigate the dual readership represented in the use of picture books. The study was conducted through in-depth interviews and observation of 9 families including 5-year-olds. The findings of this study were as follows. First, mothers exercised their exclusive right to choose books for their children. They usually used online bookstores, libraries, or book rental shops by consulting other mothers or merchandisers. On the other hand, fathers and children seldom involved themselves in the selection of picture books. Second, children preferred interesting books, while mothers favored complete series of books, which were usually for educational purposes. Third, dynamic interaction between mother and child was occurred during their daily routine of reading picture books together. Five-year-olds seemed to be transitioning into independent readers, and mothers showed that they were also readers of picture books when they appreciated and enjoyed them.

• Proceedings of the KIEE Conference
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• 1999.07g
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• pp.3230-3232
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• 1999

In this paper describes the design and improvement of a hybrid module for dual slope A/D converter. Since the input voltage to be converted is very sensitive and small. A/D converter must have the temperature stability. low-drift, and the high-resolution the conversion. A dual slop A/D converter circuit which is controlled by microprocessoer has been developed to reduce the offset voltage and the drift characteristics of operation amplifiers, and to improve the A/D conversion speed. Also hybrid module has been adapted to obtain the to obtain the stable and accurate A/D conversion for low cost use. The evaluation of the designed hybrid module has been shown as having a good performance, which will give usefull application to the industrial measurements use.

• Transactions of the Korean Society of Automotive Engineers
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• v.23 no.3
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• pp.247-253
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• 2015

Platform standardization is widely used in commercial auto industries and other industries to acquire cost reduction as well as high reliability. This paper reviews some application examples and estimates expected effect of Korean army's platform standardization for combat system and combat support system. Also, military platform standardization based on utilization of commercial vehicles has been studied with the standard vehicles used in Korean army. It is estimated that outstanding results may be achieved if a dual platform, the public and military platforms, is utilized. So, when the strategy of the military transportation system is decided, "dual use" concept is necessary and this could maximize the effect of the military strategy reinforcement.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.63.2-63.2
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• 2011

The objective of this study is to investigate the aerodynamic characteristics of a small vertical axis wind turbine with dual blade type. The Wind turbine with dual blade has various angle of attack. so this turbine improve starting characteristics. The various arrangement of the vertical axis wind turbine with dual blade is designed. Among them, it shows superior quality that is arranged in three rows. Among arrangement in three rows, we use general computational fluid dynamics program CFX to find out the optimal arrangement. By comparing the predicted results of the aerodynamic characteristics of the different arrangement of the blades, an appropriate arrangement of the blade is suggested to design the small wind turbine blade.

• Journal of applied mathematics & informatics
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• v.27 no.3_4
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• pp.567-579
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• 2009

Recently, Peng et al. proposed a primal-dual interior-point method with new search direction and self-regular proximity for LP. This new large-update method has the currently best theoretical performance with polynomial complexity of O($n^{\frac{q+1}{2q}}\;{\log}\;{\frac{n}{\varepsilon}}$). In this paper we use this search direction to propose a primal-dual interior-point method for convex quadratic programming (QP). We overcome the difficulty in analyzing the complexity of the primal-dual interior-point methods for convex quadratic programming, and obtain the same polynomial complexity of O($n^{\frac{q+1}{2q}}\;{\log}\;{\frac{n}{\varepsilon}}$) for convex quadratic programming.

• Transactions of the Korean Society of Automotive Engineers
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• v.9 no.6
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• pp.103-111
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• 2001

During cold-start period, the reduction of exhaust emissions is a challenging task. To decrease harmful gaseous substances such as HC, it is necessary to realize a fast catalyst warm-up. In this study, the performance of dual pipe exhaust system have been carried out through different test mode. From measurement of gas temperature and HC concentration, the following conclusions were derived ; 1) Compared with single pipe, dual pipe exhaust system remarkably increase temperature of exhaust gas going through M.C.C(Main Catalytic Converter). 2) W.C.C.(Warm-up Catalytic Converter) also decreases HC emission. To reduce HC emission, it is helpful to use W.C.C. as well as dual pipe exhaust system. 3) Using finite element method, it is shown that inner parts have much higher distribution of temperature than outer parts.

• The Transactions of the Korean Institute of Power Electronics
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• v.20 no.6
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• pp.573-579
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• 2015

A control algorithm of thyristor dual converter power system is proposed in this study for a railway power substation. The thyristor dual converter can use regenerative power without an additional system using control algorithm. An autonomous voltage and mode change method is also proposed to provide uninterrupted power to the railway. A 10 kW reduced model of the thyristor dual converter power system is built and tested to verify the validity of the proposed control algorithm.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.11a
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• pp.237-242
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• 2000

The areal recording density of HDD(Hard Disk Drive) has been increasing by about 60% a year. In order to achieve high areal density, less track pitch is expected and more servo bandwidth is required. Dual stage actuator and servo controller for HDD have been suggested for achieving high track density as a possible solution. Dual-loop servo system is generally classified into a two-input-two-output system, but if we use an estimator for a two-input-two-output system, it can be converted into two input one output system. Since we can't control the dual stage servo system by the classical method, it requires a special technique; for example, Parallel Loop System, Master-Slave Loop System, Decoupled Master-Slave Loop System, and Dual Feedback Loop System. In this paper, we performed experimental evaluations of several types of control algorithm. Further experiments will be made in the future.

• Journal of Information Processing Systems
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• v.13 no.6
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• pp.1516-1526
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• 2017

Many organizations today use patch management systems to uniformly manage software vulnerabilities. However, the patch management system does not guarantee the integrity of the patch in the process of providing the patch to the client. In this paper, we propose a method to guarantee patch integrity through dual electronic signatures. The dual electronic signatures are performed by the primary distribution server with the first digital signature and the secondary distribution server with the second digital signature. The dual electronic signature ensures ensure that there is no forgery or falsification in the patch transmission process, so that the client can verify that the patch provided is a normal patch. The dual electronic signatures can enhance the security of the patch management system, providing a secure environment for clients.

• Advances in Energy Research
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• v.8 no.4
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• pp.213-222
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• 2022

Our overdependence on the limited supply of fossil fuel with the burden of emission as a consequence of its utilization has been a major concern. Biodiesel is emerging as a potential diesel substitution for its similar performance, with the additional benefits of emitting lesser emissions. Due to the easy availability of feedstock for Biogas production, Biogas is studied for its use in CI engines. In this study, we considered Linseed Biodiesel and Biogas to run on dual fuel mode in a CI engine. An energy and exergy analysis was conducted to study the rate of fuel energy and exergy transformation to various other processes. Exergy relocation to exhaust gases was observed to be an average of 5% more for dual fuel mode than the diesel mode, whereas exergy relocation to the diesel mode was observed to be more than the dual fuel modes. Also, exergy loss to exhaust gas is observed to be more than the exergy transferred to cooling water or shaft. The exergy efficiency observed for biodiesel-biogas mode is only lesser by 3% compared to diesel-biogas mode, suggesting Biodiesel can be a substitute fuel for diesel.