• Education of Primary School Mathematics
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• v.25 no.2
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• pp.161-178
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• 2022

Korean uses a dual numeral system consisting of native and Chinese words. This dual numerical system is customarily selected in real life, mixed with two methods, or irregularly transformed. Therefore, the burden on both students and teachers is increased in the learning guidance process of numeral. This study recognized the need to improve the difficulty of learning guidance due to the dual numeral system. To this end, the context in which the numeral system method is selected, various modified cases, and related guidance contents of the current curriculum and textbooks were analyzed and organized. As a result of the analysis, there were characteristics of the selection and deformation of the numeral system method, which appears according to the actual situation using numerical. However, the criteria for characteristics were ambiguous and there were no specific guidance guidelines in the curriculum and textbooks. In this case, since the role of the teacher is more important, the teacher should be aware of the detailed characteristics of the actual situation related to the dual numeral system and let the student understand through experience and practice on various aspects of the use of the dual numeral system.

• Journal of Power Electronics
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• v.16 no.1
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• pp.111-120
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• 2016

Generally, a single phase H-bridge converter feeding a single primary track is employed in conventional inductive power transfer systems. However, these systems may not be suitable for some high power applications due to the constraints of the semiconductor switches and the cost. To resolve this problem, a novel dual coupled primary tracks IPT system consisting of two high frequency resonant inverters feeding the tracks is presented in this paper. The primary tracks are wound around an E-shape ferrite core in parallel which enhances the magnetic flux around the tracks. The mutual inductance of the coupled tracks is utilized to achieve adjustable power sharing between the inverters by configuring the additional resonant capacitors. The total transfer power can be continuously regulated by altering the pulse width of the inverters' output voltage with the phase shift control approach. In addition, the system's efficiency and the control strategy are provided to analyze the characteristic of the proposed IPT system. An experimental setup with total power of 1.4kW is employed to verify the proposed system under power ratios of 1:1 and 1:2 with a transfer efficiency up to 88.7%. The results verify the performance of the proposed system.

• Journal of the Korean Home Economics Association
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• v.36 no.4
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• pp.147-162
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• 1998

This study constructed a family life education program designed to help dual-earner couples reduce their role strain. This program is consisted of 6 sessions aiming for understanding the multidimensional affecting factors of role strain, strengthening family system, sharing the housework, managing time effectively reducing the additional role and adjusing standard, maintaining desirable attitude on work and family. We expect this program to be helpful in reducing dual-earner families' role strain and the active using of role strain coping strategies.

• The Pure and Applied Mathematics
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• v.20 no.2
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• pp.129-136
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• 2013

We research properties of ternary numbers with values in ${\Lambda}(2)$. Also, we represent dual ternary numbers in the sense of Clifford algebras of real six dimensional spaces. We give generation theorems in dual ternary number systems in view of Clifford analysis, and obtain Cauchy theorems with respect to dual ternary numbers.

• Journal of Institute of Control, Robotics and Systems
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• v.18 no.7
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• pp.650-657
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• 2012

An effective dual-mode camera system(a passive wide-angle camera and a pan-tilt-zoom camera) is proposed in order to improve the performance of visual surveillance. The fixed wide-angle camera is used to monitor large open areas, but the moving objects on the images are too small to view in detail. And, the PTZ camera is capable of increasing the monitoring area and enhancing the image quality by tracking and zooming in on a specific moving target. However, its FOV (Field of View) is limited when zooming in on a specific target. Therefore, the cooperation of wide-angle and PTZ cameras is complementary. In this paper, we propose an automatic initial set-up algorithm and coordinate transform method from the wide-angle camera coordinate to the PTZ one, which are necessary to achieve the cooperation. The automatic initial set-up algorithm is able to synchronize the views of two cameras. When a moving object appears on the image plane of a wide-angle camera after the initial set-up positioning, the obtained values of the wide-angle camera should be transformed to the PTZ values based on the coordinate transform method. We also develope the PTZ control method. Various in-door and out-door experiments show that the proposed dual-camera system is feasible for the effective visual surveillance.

• The Mathematical Education
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• v.19 no.2
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• pp.33-37
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• 1981

• Journal of Practical Engineering Education
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• v.11 no.2
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• pp.181-193
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• 2019

A workplace trainer is required to have profound theoretical and technological knowledge, sufficient experience and problem-solving ability in order to play the role of a competent trainer and assessor for the apprentices and experienced worker students who are participating in the Work-Learning Dual System of the company. This study has introduced a Degree-linked Highly Skilled professional Course in Korea and proposed an optimized standard education model for the training of high-quality workplace trainers. It is expected that this study will contribute greatly to the training of highly skilled professionals for efficient implementation of the Work-Learning Dual System and stable institutional settlement of the Highly Skilled professionals Course as the first empirical study on the training of highly skilled professionals.

• Journal of Physiology & Pathology in Korean Medicine
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• v.28 no.1
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• pp.9-15
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• 2014

Recently, interest in traditional medicine has increased steadily. Nations having traditional medicine system have been attempting to change it institutionally for the purpose of public application boost in use of traditional medicine. But there are not too many countries which have established the modern system of education and licensing system for traditional medicine with it maintained as a part of a national health care system. The best known examples of nations utilizing traditional medicine are the People's Republic of China, Republic of Korea, Japan, and Taiwan. These countries follow different patterns in the relationship with western medicine according to different social and historical backgrounds. Taiwan has dual medical system as Korean. In this study, we looked through history and the current state of affairs of national health care system in Taiwan, and also found out the licensing system, the educational system, and the curriculum in several universities. thoroughly. Furthermore, we looked into the direction of the policy of Taiwanese health care system which has been becoming an integrated medical system between traditional Chinese medicine and western medicine. With findings based on this study, we deduced implications of a future policy line about the integrated medical system in Korea to minimize conflicts between the concerned parties.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.41 no.3
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• pp.207-212
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• 2005

Dual frequency acoustic pinger(AP) was manufactured to reduce study effect by long-term use of developed single frequency AP to prevent cetacean bycatch. Directivity characteristic of transducer was the omnidirectional pattern which showed less than ${\pm}3dB$ the change range of sensitivity on the beam pattern of right and left. Source power level(SPL) was 1384311pa with epoxy window before casing however after casing 1170B11Pa at sea. Dual frequency Af was tested to identify the avoidance behavior of bottlenose dolphin by its working. However the efficiency of dual frequency AP about the study effect was verified experiment repeatedly using single and dual frequency AP.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.17 no.2
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• pp.30-41
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• 2021

This paper presents the heating performance analysis results of a heat pump system using a dual heat source. In this paper, a dual heat source refers to the ground-coupled heat exchanger using both a surface water heat exchanger (SWHE) and a vertical ground heat exchanger (VGHE). In order to evaluate the system performance, we installed a monitoring system to measure the temperature and power consumption of a heat pump and then collected operation data with 4 different load burdened ratios of the dual heat source heat exchanger. During the whole measurement period, the average heating capacity of a water-to-water heat pump unit was 37.3 kW. In addition, the compressor of the heat pump consumed 9.4 kW of power, while the circulating pump of the dual heat source heat exchanger used 6.7 kW of power. Therefore the average heating coefficient of performance (COP) for the heat pump unit was 4.0, while the entire system including the circulating pump was 2.7. Finally, the parallel use of SWHE and VGHE was beneficial to the system performance; however, further researches are needed to optimize the design data for various load ratios of the dual heat source heat exchanger.