• Bulletin of the Korean Chemical Society
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• v.35 no.5
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• pp.1299-1304
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• 2014

The electrochemical performance of Li-S cells was investigated in various ternary electrolyte solutions composed of 1,2-dimethoxyethane (DME), tetra(ethylene glycol) dimethyl ether (TGM), and 1,3-dioxolane (DOX). The discharge capacity values and cycle data obtained at each composition were statistically treated with the Minitab program to obtain mixture contour plots, from which the optimal composition of the ternary solvent systems was predicted. The discharge capacities and capacity retention were quite dependent on the electrolyte composition. It was estimated from the contour plots of the capacity at 1.0 C that the discharge capacity sharply increased with a decrease in the TGM content. High capacities greater than 900 mAh/g at 1.0 C were expected for the electrolyte composition with a volume ratio of DME/TGM/DOX = 1/0/1. In contrast, it was predicted from the mixture contour plot of the capacity retention that the cycle performance would significantly increase with an increase in the DME content.

• Journal of international Conference on Electrical Machines and Systems
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• v.1 no.4
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• pp.412-418
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• 2012

Eddy current brakes are electromechanical devices used as variable mechanical loads for testing electrical machines. Accurate modeling of eddy current loss is an important t factor for optimum design of eddy brake systems. In this second part, we propose novel formulations of eddy current loss in novel claw-pole eddy brake system. The proposed model for eddy current loss in novel claw-pole eddy brake system depends on the size of the claw poles. Also, in this paper, the flux density is measured by using the magnetic circuit of the novel claw pole. The model results are compared with experimental results and they are found to be in good agreement.

• Journal of information and communication convergence engineering
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• v.12 no.4
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• pp.263-270
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• 2014

Corner detection and feature extraction are essential aspects of computer vision problems such as object recognition and tracking. Feature detectors such as Scale Invariant Feature Transform (SIFT) yields high quality features but computationally intensive for use in real-time applications. The Features from Accelerated Segment Test (FAST) detector provides faster feature computation by extracting only corner information in recognising an object. In this paper we have analyzed the efficient object detection algorithms with respect to efficiency, quality and robustness by comparing characteristics of image detectors for corner detector and feature extractors. The simulated result shows that compared to conventional SIFT algorithm, the object recognition system based on the FAST corner detector yields increased speed and low performance degradation. The average time to find keypoints in SIFT method is about 0.116 seconds for extracting 2169 keypoints. Similarly the average time to find corner points was 0.651 seconds for detecting 1714 keypoints in FAST methods at threshold 30. Thus the FAST method detects corner points faster with better quality images for object recognition.

• Proceedings of the KAIS Fall Conference
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• 2011.12b
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• pp.394-397
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• 2011

The effects of heat input(1.4~3.2kJ/mm), shielding gas(Ar80%+$CO_2$20%) and postweld heat treatment(PWHT, $600^{\circ}C$, 40hr.) on the TMCP HSB600 steel weldments made by GMAW process were investigated. The tensile strength and CVN impact energy of as-welded specimens decreased with increasing heat input. The fine-grained acicular ferrite was mainly formed in the low heat input while polygonal and side plate ferrites were dominated in the high inputs. High performance steel for bridges requires higher performance in tensile and yield strength, toughness, weldability, etc. Thus, the purpose of the experiment is to study HSB 600 in GMAW.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.8
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• pp.3488-3500
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• 2020

At the present time, the economy continues to flourish, and private cars have become the means of choice for most people. Therefore, the license plate recognition technology has become an indispensable part of intelligent transportation, with research and application value. In recent years, the convolution neural network for image classification is an application of deep learning on image processing. This paper proposes a strategy to improve the YOLO model by studying the deep learning convolutional neural network (CNN) and related target detection methods, and combines the OpenCV and TensorFlow frameworks to achieve efficient recognition of license plate characters. The experimental results show that target detection method based on YOLO is beneficial to shorten the training process and achieve a good level of accuracy.

• Transactions of the Korean Society of Automotive Engineers
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• v.24 no.5
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• pp.575-580
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• 2016

This paper sought to find a way to improve the fuel consumption rate of a vehicle for the Shell Eco-marathon Asia 2014, with a special focus on the correlation between vehicle dynamics, aerodynamics and chassis weight reduction. In 'KUTY-Eco 1' designed for SEM Asia 2014, a chassis made with an aluminum alloy tube, semi-monocoque structure and a pivot steering system were adopted to reduce weight and to secure better performance. The goals were achieved using computer-aided engineering(CAE) and parameter study. Finally, 'KUTY-Eco 1' was created, the lightest car in the competition's prototype petrol(gasoline) type category. 'KUTY-Eco 1' secured the official record of 142.7 km/liter during the competition.

• Steel and Composite Structures
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• v.33 no.3
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• pp.333-346
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• 2019

Foam ceramic materials contribute to the explosion effect weakening on concrete structures, due to the corresponding excellent energy absorption ability. The blast resistance of concrete members could be improved through steel-foam ceramics as protective cladding layers. An approach for the modeling of dynamic response of steel-foam ceramic protected reinforced concrete (Steel-FC-RC) slabs under blast loading was presented with the LS-DYNA software. The orthogonal analysis (five factors with five levels) under three degrees of blast loads was conducted. The influence rankings and trend laws were further analyzed. The dynamic displacement of the slab bottom was significantly reduced by increasing the thickness of steel plate, foam ceramic and RC slab, while the displacement decreased slightly as the steel yield strength and the compressive strength of concrete increased. However, the optimized efficiency of blast resistance decreases with factors increase to higher level. Moreover, an efficient design method was reported based on the orthogonal analysis.

• Journal of The Korean Association of Information Education
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• v.15 no.1
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• pp.51-58
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• 2011

Recently, STEM education and improvement in creativity took a lot of attention in local and foreign educational programs, and the robot education is regarded as one of the answers which can achieve the objectives. The robot education is quite active locally in various ways including robot classes for after school program in elementary schools, a number of robot competitions, and education for the gifted. Under these circumstances, the qualification test for robot technology is developed to provide a standard for evaluating professional knowledge on robotics and is currently under consideration to be one of the government-approved qualification tests. However, compared to the robot classes for after school program, this test is not well recognized by most teachers in elementary and middle schools. This paper addresses and analyzes the current status of the test, in particular, backgrounds, qualification standards, organizing committee, intention of presenting questions, examples of problems used in the test, and demands raised by applicants, etc. Base on the analysis, some suggestions are made to establish a solid standard for evaluating robot technologies. It is suggested that the level of difficulty and contents covered should be properly adjusted considering the level of applicants. In addition, it is essential to provide well organized supplementary material for students and wide range of contents on robot technology. Finally, some efforts including cooperating with the robot classes for after school program should be made to invigorate the test.

• Journal of Korean Home Economics Education Association
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• v.22 no.2
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• pp.31-43
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• 2010

We investigated the extent of recognition and the rate of class practice on the contents relevant to the environmental education in the units of 'Clothing Life' of the 7th 'Technology-Home Economics' curriculum in Korean middle school teachers. Two hundred sixty teachers, who had taught the units of 'Clothing Life' and responded to the questionnaires by mail from December 2007 to January 2008, were enrolled and each item in the questionnaires was analyzed in this study. Most teachers recognized the serious environmental issues in their residential area resulting in a harmful influence on their lives. Also they exhibited increased practice will such as joining to the environmental organizations and showed high practice of the environmental preservation. They commented relatively high rate of class practice on the contents relevant to the environmental education and enhanced practice of the environmental preservation in all units of 'Clothing Life' of the 7th 'Technology-Home Economics' curriculum except the units of 'Clothing Skill and Dress Clothes' and 'Simple Clothes Making'. Moreover, teachers with higher age and longer teaching career had the higher level of recognition and the greater rate of class practice on the environmental education compared to those without. Teachers should try to raise the students' recognition and practice will on the environmental issues in the class of 'Clothing Life' of the 7th 'Technology-Home Economics' curriculum in Korean middle school.

• Proceedings of the KIEE Conference
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• 2002.07a
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• pp.548-550
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• 2002

In this paper the domestic and worldwide trends of substation automation are described in order to cope with the coming new environment in this part On the world market of substation control it will be change from analog technology to digital technology. And the technology of a system integration relevant to a substation automation become more important than that of individual power apparatus. Therefore development of substation automation technology is needed.