• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2018.06a
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• pp.129-129
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• 2018

Hard coating application is effective way of cutting tool for hard-to-machine materials such as Inconel, Ti and composite materials focused on high-tech industries which are widely employed in aerospace, automobile and the medical device industry also Information Technology. In cutting tool for hard-to-machine materials, high hardness is one of necessary condition along with high temperature stability and wear resistance. In recent years, high-entropy alloys (HEAs) which consist of five or more principal elements having an equi-atomic percentage were reported by Yeh. The main features of novel HEAs reveal thermodynamically stable, high strength, corrosion resistance and wear resistance by four characteristic features called high entropy, sluggish diffusion, several-lattice distortion and cocktail effect. It can be possible to significantly extend the field of application such as cutting tool for difficult-to-machine materials in extreme conditions. Base on this understanding, surface coatings using HEAs more recently have been developed with considerable interest due to their useful properties such as high hardness and phase transformation stability of high temperature. In present study, the nanocomposite coating layers with high hardness on WC substrate are investigated using high entropy alloy target made a powder metallurgy. Among the many surface coating methods, reactive magnetron sputtering is considered to be a proper process because of homogeneity of microstructure, improvement of productivity and simplicity of independent control for several critical deposition parameters. The N2 is applied to reactive gas to make nitride system with transition metals which is much harder than only alloy systems. The acceleration voltage from 100W to 300W is controlled by direct current power with various deposition times. The coating layers are systemically investigated by structural identification (XRD), evaluation of microstructure (FE-SEM, TEM) and mechanical properties (Nano-indenter).

• The Journal of Dong Guk Oriental Medicine
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• v.4
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• pp.189-209
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• 1995

The purpose of this study is to understand a term of 'Jangbu theory 臟腑論' in 'Dong-Eui-Su-Se-Bo-Won 東醫壽世保元'. The conclusion would be summerized as follows. 1. 'Jangbu theory 臟腑論' of 'Sa-Sang medicine 四象醫學' is based on 'Sa-Sang structure 四象構造'. 2. 'Mind 心' of 'Sa-Sang medicine 四象醫學' is recognised as the Lord of body. 3. 'four-Jang 四臟' and 'four-Bu 四腑' constitute 'Sa-Sang structure 四象構造' which is based on the deviation of 'vital energy 氣', and 'four-Jang 四臟' plays a loading role. 4. 'Sacho 四焦' explains the whole function of human body including one's heart's desire, physical constitution and the visceral physiology. 5. 'ear-eye-nose-mouth 耳目口鼻' is connected with 'the profound secrets of nature 天機' and also has a close relation with creation of 'spirit-vital energy-blood-essence 神氣血精' and spiritual fuction. 6. 'SaHae theory 四海論' of 'Dong Mu 東武' is philosophical concept set on the basis of 'nature 天性' and 'life 人命'. 7. 'spirit-vital energy-blood-essence 神機血精' doesn't have the relation of mutual transformation. It's creation and consumption lies on 'the power of ear-eye-nose-mouth 耳目口鼻之力'. 8. 'Sa-Sang medicine 四象醫學' expands its theory centering on the deviation of 'vital energy 氣' and the transversal circulation of 'SaHae 四海' According to the above result, 'Jangbu theory 臟腑論' in 'Dong-Eui-Su-Se-Bo-Won 東醫壽世保元' should be understood on the basis of 'Sacho 四焦' and 'SaHae 四海' according to 'Sa-Sang structure 四象構造', accompanying philosophical thinking focused on human and society, the centural concept of 'Jangbu theory 臟腑論' could be said as 'Mind 心' to be the Lord of body.

• Hwankyungkyoyuk
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• v.22 no.3
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• pp.15-30
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• 2009

This study focuses on the comparison of PBL and GBS. PBL is a famous model that emphasizes diversity of students and self directed learning within the theory of constructivism. GBS has not been studied that extensively. GBS is most similar to PBL but this model has not been actively applied to school education. This study focuses on how to enhance students' interest in an educational environment that is encompassing a new and changing teach-learn paradigm and the development of new technology. Furthermore, PBL and GBS methods were compare actively applied to "Environmental Education" to make the students learn self-directed education through the transformation of one's environmental awareness. Specifically, the models were applied to the "Ecology and Environment" subject taught in general high schools and the degree of 'environmental literacy' were measured, From March to May of 2007, the PBL and GBS models were applied to 3rd grade students at D high school and the subject was 'Ecology and Environment'. The students were divided according to age into groups of $5{\sim}7$. The PBL group attempted to solve the given problems and the GBS group carried out their missions. In conclusion, after analyzing the 'environmental literacy' survey results by SPSS 12.0, just 'Knowledge of Ecology (KEOC)' and 'Locus of Control (LOC)' were slightly significant in PBL. This shows that PBL enhances the students' problem solving ability and thinking power. This is a result of the enhancement of students' problem-solving and thinking abilities through PBL. Students can learn many things because they completed their projects based on their experience and knowledge, both individually and interpersonally. We have to study how to apply PBL and GBS to the education field in spite of the many limited conditions. Therefore, this study looks at the application of PBL and GBS in environmental education and suggests specific strategies for educators who want to apply GBS and PBL and adapt them into their education curricula.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.46 no.10
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• pp.1-7
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• 2009

Nowadays there are many studies and there's huge development about RFID and WSN which have great developmental potential to many kinds of applications. In particular, the healthcare field is expected to could be securing international competitive power in u-Healthcare and combined medical treatment industry and service. More and more real time application apply RFID and WSN technology to identify, data collect and locate objects. Wide deployment of RFID and WSN will generate an unprecedented volume of primitive data in a short time. Duplication and redundancy of primitive data will affect real time performance of application. Thus, emerging applications must filter primitive data and correlate them for complex pattern detection and transform them to events that provide meaningful, actionable information to end application. In this paper, we design a complex event processing system. This system will process RFID and WSN primitive data and event and perform data transformation. Integrate RFID and WSN system had applied each now in medical treatment through this study and efficient data transmission and management forecast that is possible.

• The Journal of the Korea institute of electronic communication sciences
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• v.12 no.6
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• pp.1027-1034
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• 2017

In this paper, we propose a new function embedding method that can measure mathematical projections of probability amplitude, probability, average expectation and matrix elements of stationary-state unit matrix at all control operation points of quantum gates. The function embedding method in this paper is to embed orthogonal normalization condition of probability amplitude for each control operating point into a binary scalar operator by using Dirac symbol and Kronecker delta symbol. Such a function embedding method is a very effective means of controlling the arithmetic power function of a unitary gate in a unitary transformation which expresses a quantum gate function as a tensor product of a single quantum. We present the results of evolutionary operation and projective measurement when we apply the proposed function embedding method to the ternary 2-qutrit cNOT gate and compare it with the existing methods.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2002.05a
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• pp.598-601
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• 2002

In this research, robustness of image watermarking mixed Key and Logo scheme was evaluated. A personal ID of a copyrighter was key and watermark was logo image. The standard images of Baboon, Cameraman and Lena were used for experimental images, binary image‘Park’of 32$\times$32 and 64$\times$64 size were used for the watermark image, respectively. for robustness evaluation of the watermark, reconstructive rates of the watermark were obtained from images inserted watermark with image transformation or JPEG lossy compression. The experimental results show that the reconstructive rates of the case of 32$\times$32 watermark was better than the case of the 64$\times$64 watermark; average 5.9%, 13.9%, 6.5%, and 4.2% in the case of scale-down rates, rotational rates, impulse noise power density, and JPEG lossy compression rates, respectively.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.21-22
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• 2008

In the paper, we report several experimental data capable of evaluating the phase transformation characteristics of $Ag_x(Ge_2Sb_2Te_5)_{1-x}$ (x =0, 0.05, 0.1) thin films. The $Ag_x(Ge_2Sb_2Te_5)_{1-x}$ phase change thin films have been prepared by thermal evaporation. The crystallization characteristics of amorphous$Ag_x(Ge_2Sb_2Te_5)_{1-x}$ thin films were investigated by using nano-pulse scanner with 658 nm laser diode (power; 1~17 mW, pulse duration; 10~460 ns) and XRD measurement. It was found that the more Ag is doped, the more crystallization speed was 50 improved. In comparision with $Ge_2Sb_2Te_5$ thin film, the sheet resistance$(R_{amor})$ of the amorphous $Ag_x(Ge_2Sb_2Te_5)_{1-x}$ thin films were found to be lager than that of $Ge_2Sb_2Te_5$ film($R_{amor}$ $\sim10^7\Omega/\square$ and $R_{cryst}$ 10 $\Omega/\square$). That is, the ratio of $R_{amor}/R_{cryst}$ was evaluates to be $\sim10^6$ This is very helpful to writing current reduction of phase-change random acess memory.

• Smart Structures and Systems
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• v.25 no.1
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• pp.65-80
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• 2020

In order to protect a structure over its full life cycle, a novel tuned mass damper (TMD), the so-called semi-active eddy current pendulum tuned mass damper (SAEC-PTMD), which can retune its frequency and damping ratio in real-time, is proposed in this study. The structural instantaneous frequency is identified through a Hilbert-Huang transformation (HHT), and the SAEC-PTMD pendulum is adjusted through an HHT-based control algorithm. The eddy current damping parameters are discussed, and the relationship between effective damping coefficients and air gaps is fitted through a polynomial function. The semi-active eddy current damping can be adjusted in real-time by adjusting the air gap based on the linear-quadratic-Gaussian (LQG)-based control algorithm. To verify the vibration control effect of the SAEC-PTMD, an idealized linear primary structure equipped with an SAEC-PTMD excited by harmonic excitations and near-fault pulse-like earthquake excitations is proposed as one of the two case studies. Under strong earthquakes, structures may go into the nonlinear state, while the Bouc-Wen model has a wild application in simulating the hysteretic characteristic. Therefore, in the other case study, a nonlinear primary structure based on the Bouc-Wen model is proposed. An optimal passive TMD is used for comparison and the detuning effect, which results from the cumulative damage to primary structures, is considered. The maximum and root-mean-square (RMS) values of structural acceleration and displacement time history response, structural acceleration, and displacement response spectra are used as evaluation indices. Power analyses for one earthquake excitation are presented as an example to further study the energy dissipation effect of an SAECPTMD. The results indicate that an SAEC-PTMD performs better than an optimized passive TMD, both before and after damage occurs to the primary structure.

• Journal of the Ergonomics Society of Korea
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• v.27 no.3
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• pp.71-79
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• 2008

Walking shoes for walking and jogging have been used to enjoy lots of leisure time. Functional shoes such as walking shoes have special functions to improve body motility by changing of shoe shapes. The walking shoes could improve the motility by structural transformation of outsole as increase degrees of heel and toe. The study on insoles has not been conducted enough on the contrary of the study of outsole. The purpose of this study is to perform ergonomics analysis whether the Arch Supported insoles have an improving effect of muscle activities or not. Experiments were performed with 6 subjects who are health and haven't experienced any diseases past. EMG(Electromyography) and Foot Pressures were measured repeatedly for 5 seconds at 0 hour, after 1 hour and after 2 hours of walking. Insoles used for experiment are normal insole, insole inserted Arch Support and pad. The electrodes for EMG measurement were set on waist (erector spinae), and thigh (vastus lateralis), calf (gastrocnemius). Evaluations of EMG were analyzed by shift of MF (Median Frequency) and MPF (Mean Power Frequency). Foot Pressure was analyzed by mean pressure of feet and change of walking time. As results, Arch Support insole had larger frequency shift value than that of normal insole. Frequency shift between Arch Support insoles and normal insole showed significant difference on 95% confidence interval. And insole 1 has the highest value of frequency shift. For results of foot pressure, Arch Support insoles show continuous decreasing tendency when comparing with normal insoles by changing of times. Also, insole 1 has the highest decreasing value of foot pressure. Therefore, this study presented that the Arch Support insole can promote muscle activities and improves comfort for a prolonged walking.

• Journal of The Korean Association of Information Education
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• v.8 no.3
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• pp.365-372
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• 2004

The purpose of this study is to develop FVU, which enables teachers effectively to construct self-page on the screen, to reduce the size of file for teaching, and to correct many different kinds of event which was already made in the previous. The instrument used in the development of this Editor is UML(Unified Modeling Language), which is object-oriented methodology. The Authoring tool developed in this study is named FVU. The first page which is needed in class can be constructed by using VUEditor in FVU. Using VUEditor can get Instructional Syllabus exported into VUAuthor through Vector-transformation. Through this procedure, the size of image file comes to be reduced into forming low band width, which results in solving the problem of network traffic. Also, Instructor can create image, shape and text, and delete and correct errors or mistakes which make in the course of constructing materials for teaching. In conclusion, this VUEditor enables program designer to construct the first page, even without using such applied program as Image Tool and Power Point. This VUEditor makes instructor to make some contents for teaching easily.