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The Effect on Images of an Engineering Program Participate toward 'Engineering' and 'Technology' through Semantic Differential Method (공학캠프를 통한 공학과 기술에 대한 이미지 변화 연구)

  • Lim, Nha Young;Lee, Chang Hoon
    • Journal of Engineering Education Research
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    • v.20 no.6
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    • pp.68-75
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    • 2017
  • This study has a purpose to analyse changes in perception and image about engineering and technology of students who participated in the engineering camp. To achieve this objective, the questions were as follows. 1) What about participants' image difference for engineering before and after participating the engineering camp 2) What about participants' image difference for technology before and after participating the engineering camp. For this study, the program was progressed from Aug in 2017 and the data was collected from 88 students, middle school seniors and high school freshmen. The results of this study were as follows: First, secondary students perceived 'valuable(6.74)', 'meaningful(6.73)', 'rich(6.40)', 'collaborative(6.42)', 'nice(6.22)' as high image rank of the positive response for engineering. On the other hand, 'complex(3.59)', 'labored(3.80)', 'hard(4.66)', 'dangerous(4.48)', 'cold(4.86)' were perceived as low image rank of the negative response for engineering. We can realize that they generally has the image that engineering is valuable, meaningful and nice but also labored, complex and hard. The students who participated in the engineering camp showed the greatest difference in 'complex - simple' and 'dangerous - safe' engineering categories before and after the camp, followed by 'cold - hot', 'labored - easy', and 'hard - soft', respectively. Second, secondary students perceived 'meaningful(6.58)', 'valuable(6.55)', 'wide(6.38)', 'nice(6.37)', 'strong(6.25)' as high image rank of the positive response for technology. On the other hand, 'complex(3.85)', 'labored(3.93)', 'hard(4.62)', 'dangerous(4.72)', 'cold(5.05)' were perceived as low image rank of the negative response for technology. The students who participated in the engineering camp had the big change in 'hard - soft' technology category before and after the camp, followed by 'complex - simple', 'labored - easy', 'theoretical - practical' and 'dangerous - safe', respectively. We can see that the negative images for technology which were complex, labored, dangerous, theoretical was improved with positive image such as simple, easy, safe and practical, after conducting the engineering camp. In conclusion, both image recognitions for engineering and technology have improved after the camp. It means that interesting and entertaining engineering-technology program can boost interests in engineering and technology which felt difficult, so that images about them can be turned out positive. Also, it is possible to reduce avoidance of natural science and engineering subjects, as part of the purpose of training creative talents in science and engineering, so it can be said that the engineering camp is highly meaningful because it can lead students into the field of science and engineering.

A Study on the Application of UNIDROIT Principles in International Commercial Transaction (국제상거래에서의 UNIDROIT원칙 적용에 관한 연구 - 국제물품매매계약에 관한 유엔협약(CISG)과의 비교를 중심으로 -)

  • Woo, Kwang-Myung
    • International Commerce and Information Review
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    • v.14 no.3
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    • pp.453-479
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    • 2012
  • The increase in international trade is clearly reflected by litigation and arbitration. Despite the importance of international commercial transaction, until very recently little was known about how the law interacts with actual practice. The CISG obviously plays an important role, but we are concerned with using choice of law to resolve issue that the CISG leaves unresolved. The case law UPICC is now accessible by means of UNILEX, the database on international case law that focus on CISG cases. The courts and arbitration tribunals throughout the world are developing a growing body of international case law on issues not resolved by the CISG, though arising from transactions to which the CISG applies. The application of the CISG is obligatory due to its nature as hard law an international convention. However, UPICC are only restatements and more flexibility, comprehensive instrument than CISG. This article offers to promote the UPICC application from their present status as a mere soft law instrument through analysing UNILEX cases.

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Application of Motor Drive System Using Resonant Voltage-Type Inverter (공진형 전압형 인버터의 전동기구동 시스템 응용)

  • Kim, Yong-Joo;Ma, Young-Ho;Kim, Han-Sung;Che, Geou-Ha;Kim, Byung-Joo
    • Proceedings of the KIEE Conference
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    • 1991.11a
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    • pp.164-166
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    • 1991
  • This paper achieved by Pulse-Withed Modulation of the inverter switchs. But Conventional PWM inverter is employed hard switching by means a switching device. Moreover, this paper presents resonant DC link Voltage type inverter thet it was not necessary snubber circuit and dead time and modeling of motor drive control system and simulating analysis are discussed.

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COMPUTER SIMULATION OF MAGNETIC PROPERRTIES OF SPRING MAGNETS

  • Kitajima, N.;Inoue, H.;Kanai, Y.;Fukunaga, H.
    • Journal of the Korean Magnetics Society
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    • v.5 no.5
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    • pp.404-407
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    • 1995
  • Magnetic properties of model exchange-spring magnets, which are composed of magnetically soft and hard grains, were calculated by means of computer simulation. The dependence of the magnetic properties on the strength of intergrain exchange interaction and the amount of soft grains was studied. The existence of soft grains enhanced the remanence remarkably, and the remanence over $0.8M_{s}$ was obtained in the model magnets containing 25% or more soft grains by volume. The calculated coercivity vs. the strength of the exchange interaction curves showed a peak at a critical strength of the exchange interaction, although the remanence increased monotonously with increase in the strength of the exchange interaction. Thus the maximum energy product also reached a peak around the same critical strength. The calculated maximum energy product exceeded $300kJ/m^{3}$ when the magnet is assumed to be composed of $Fe_{3}B$ and $Nd_{2}Fe_{14}B$.

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The Shot Change Detection Using a Hybrid Clustering (하이브리드 클러스터링을 이용한 샷 전환 검출)

  • Lee, Ji-Hyun;Kang, Oh-Hyung;Na, Do-Won;Lee, Yang-Won
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • v.9 no.2
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    • pp.635-638
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    • 2005
  • The purpose of video segmentation is to segment video sequence into shots where each shot represents a sequence of frames having the same contents, and then select key frames from each shot for indexing. There are two types of shot changes, abrupt and gradual. The major problem of shot change detection lies on the difficulty of specifying the correct threshold, which determines the performance of shot change detection. As to the clustering approach, the right number of clusters is hard to be found. Different clustering may lead to completely different results. In this thesis, we propose a video segmentation method using a color-X$^2$ intensity histogram-based fuzzy c-means clustering algorithm.

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A Genetic Approach for Joint Link Scheduling and Power Control in SIC-enable Wireless Networks

  • Wang, Xiaodong;Shen, Hu;Lv, Shaohe;Zhou, Xingming
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.4
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    • pp.1679-1691
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    • 2016
  • Successive interference cancellation (SIC) is an effective means of multi-packet reception to combat interference at the physical layer. We investigate the joint optimization issue of channel access and power control for capacity maximization in SIC-enabled wireless networks. We propose a new interference model to characterize the sequential detection nature of SIC. Afterward, we formulize the joint optimization problem, prove it to be a nondeterministic polynomial-time-hard problem, and propose a novel approximation approach based on the genetic algorithm (GA). Finally, we discuss the design and parameter setting of the GA approach and validate its performance through extensive simulations.

The Development of MILS Software based on RTX for Real-time Imitation of an Inertial Navigation System (관성항법장치의 실시간 모의를 위한 RTX기반의 MILS S/W 개발)

  • Kim, Ki-Pyo;Choi, Jin-Ho;Ahn, Kee-Hyun;Woo, Deog-Young
    • Journal of the Korea Institute of Military Science and Technology
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    • v.14 no.3
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    • pp.353-358
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    • 2011
  • In this paper, we have introduced a Missile In the Loop Simulation(MILS) Software developed for the missile ground test, which is based on a commercial hard real-time operating system(OS) on Windows platform called as Real-Time eXtension(RTX). MILS software makes it possible to test overall system functions of a integrated missile on the ground in the flight conditions by real-time imitating its inertial data. By means of MILS, we have performed missiles ground tests, which result in successful real flight tests.

The Control System Modeling and Experiment for the Tele-operated Unmanned Vehicle

  • Duk sun Yun;Lee, Woon-Sung;Kim, Jung-Ha
    • Journal of Mechanical Science and Technology
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    • v.16 no.10
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    • pp.1253-1263
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    • 2002
  • The control system design and modeling of an unmanned vehicle by means of a new concept for better performance through a tole-operation system is suggested by sensor fusion. But, the control of a real vehicle is very difficult, because the system identification of the vehicle is hard to find the unknown factors and the disturbances of the experimental environment. For the longitudinal and lateral controls, the traction system and steering system models are set up and a tuning method to find the gain of the controller by experiments is presented. In this research, mechanical and electronic parts are implemented to operate the unmanned vehicle and data reconstruction method of information about the environment data coming from several sensors is presented by data plot for the vehicle navigation. This paper focuses on the integration of tole-operated unmanned vehicle. This vehicle mainly controlled lateral and longitudinal directions with actuators for controlling vehicle movement and sensors for the closed-loop controlled system.

A Study on the Design of Multi-FNN Using HCM Method (HCM 방법을 이용한 다중 FNN 설계에 관한 연구)

  • Park, Ho-Sung;Yoon, Ki-Chan;Oh, Sung-Kwun
    • Proceedings of the KIEE Conference
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    • 1999.11c
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    • pp.797-799
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    • 1999
  • In this paper, we design the Multi-FNN(Fuzzy-Neural Networks) using HCM Method. The proposed Multi-FNN uses simplified inference as fuzzy inference method and Error Back Propagation Algorithm as learning rules. Also, We use HCM(Hard C-Means) method of clustering technique for improvement of output performance from pre-processing of input data. The parameters such as apexes of membership function, learning rates and momentum coefficients are adjusted using genetic algorithms. We use the training and testing data set to obtain a balance between the approximation and the generalization of our model. Several numerical examples are used to evaluate the performance of the our model. From the results, we can obtain higher accuracy and feasibility than any other works presented previously.

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BOTTOM IrMn-BASED SPIN VALVES BY USING OXYGEN SURFACTANT

  • J. Y. Hwang;Kim, M. Y.;K. I. Jun;J. R. Rhee;Lee, S. S.;D. G. Hwang;S. C. Yu;Lee, S. H.
    • Proceedings of the Korean Magnestics Society Conference
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    • 2002.12a
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    • pp.62-63
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    • 2002
  • To reach 100 Gbit/in$^2$ magnetic recording densities in hard disk drives specular enhancement of giant magnetoresistance (GMR) effect in spin valve (SV) films has become one of the indispensable means for application as read elements in recording heads [1]. More recently specular spin valve (SSV) structure containing nano-oxides layers (NOL) were reported [2], where MR enhancement is caused to extended mean free path of majority spin polarized electrons through specular reflection at metal/insulator interfaces [3] in the SV films. (omitted)

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