• Title/Summary/Keyword: alternative position

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A Study on the Development Direction for the Education for Sustainable Development of the Ecologically-oriented Alternative Elementary School (생태지향형 초등대안학교의 지속가능발전교육을 위한 발전방안 연구)

  • Shin, Ji-Yeon;Choi, Don-Hyung
    • Hwankyungkyoyuk
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    • v.25 no.2
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    • pp.272-289
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    • 2012
  • The purpose of this study is to compare and analyze the educational philosophy, goal, method, content, and environment of ecologically-oriented alternative elementary schools and suggest several practical methods for alternative education. Both ecologism and alternative education pursue sustainable values. The educational content of ecologically-oriented alternative elementary schools, analyzed from the view of sustainable development, focuses most on the natural resources, biodiversity, and sustainable food production, and also include human rights, peace and security, unification, cultural diversity, and health food in terms of the social sustainability and sustainable production and consumption concerning economic sustainability. This study should help environmental education become establish its possibility and position as alternative education and be recognized of its educational value. Furthermore, based on the cases of ecologically-oriented alternative elementary schools that are becoming 'garden of environmental education' as sustainable development education, it should lead to 'education communicating with environmental education at schools'.

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Automatic Automobile Control System with Multi-Sensor (다중센서를 이용한 무인자동차 제어시스템)

  • Han, Chang-Woo;Choi, Won-Sik
    • Journal of the Korean Society of Industry Convergence
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    • v.4 no.3
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    • pp.339-347
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    • 2001
  • Automatic automobile has been studied as the alternative energy system and the production flow automation device recently. But this is dependent on the import production, and its position cannot be controlled free from the fixed path. It is difficult to control the automobile position because of the eccentricity of inertia monent, slip and roughness between wheel and road surface. This problems is solved for the controller to be feedbacked the data of the multi-sensor system consisting of the rotary encoder and electronic compass. The proportional Integrated controller in the modified Ziegler-Nichols method is made up with Hitachi 7034 microprocessor. To the real time control the mechanical, electrical and electronic hardware and software device is produced by myself. The RF data of automobile speed and position is supplied to the remote PC to be displayed the automobile condition. By the experinent of the forward, spin, point path planning, it is known for autombile.

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Regional Alternative Navigation Using HALE UAV, Pseudolite & Transceiver (고고도 장기체공 무인기와 의사위성/트랜시버를 활용한 국지적 대체항법에 관한 연구)

  • Choi, Min-woo;Yu, Sun-Kyoung;Kim, O-Jong;Kee, Chang-Don;Park, Byung-Woon;Seo, Seung-Woo;Park, Jun-Pyo
    • Journal of Advanced Navigation Technology
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    • v.19 no.6
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    • pp.499-506
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    • 2015
  • Global navigation satellite systems (GNSS) is operating widely in civil and military area. GNSS signals, however, can be easily interfered because its signal is vulnerable to jamming. Thus, a sort of backup or alternative system is needed in order that the navigation performance is assured to a certain degree in case of GNSS jamming. In order to suggest a series of backup or alternative system of regional navigation, in this paper, we introduced a high altitude long endurance unmanned aerial vehicle (HALE UAV) with pseudolites using inverted GPS and transceiver system. We simulated the positioning error of the regional navigation system using HALE UAV with inverted GPS or transceivers concepts. We estimated the position error of HALE UAV calculate user position errors based on the position error of HALE UAV and general pseudorange error.

Improving the Performance of AODV(-PGB) based on Position-based Routing Repair Algorithm in VANET

  • Jung, Sung-Dae;Lee, Sang-Sun;Oh, Hyun-Seo
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.4 no.6
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    • pp.1063-1079
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    • 2010
  • Vehicle ad hoc networks (VANET) are one of the most important technologies to provide various ITS services. While VANET requires rapid and reliable transmission, packet transmission in VANET is unstable because of high mobility. Many routing protocols have been proposed and assessed to improve the efficiency of VANET. However, topology-based routing protocols generate heavy overhead and long delay, and position-based routing protocols have frequent packet loss due to inaccurate node position. In this paper, we propose a position-based routing repair algorithm to improve the efficiency of VANET. This algorithm is proposed based on the premise that AODV (-PGB) can be used effectively in VANET, if the discovery, maintenance and repair mechanism of AODV is optimized for the features of VANET. The main focus of this algorithm is that the relay node can determine whether its alternative node exits and judge whether the routing path is disconnected. If the relay node is about to swerve from the routing path in a multi-hop network, the node recognizes the possibility of path loss based on a defined critical domain. The node then transmits a handover packet to the next hop node, alternative nodes and previous node. The next node repairs the alternative path before path loss occurs to maintain connectivity and provide seamless service. We simulated protocols using both the ideal traffic model and the realistic traffic model to assess the proposed algorithm. The result shows that the protocols that include the proposed algorithm have fewer path losses, lower overhead, shorter delay and higher data throughput compared with other protocols in VANET.

TV용 패널 검사대 최적조명설계에 관한 연구

  • 조항준;김성환;정의승
    • Proceedings of the ESK Conference
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    • 1995.04a
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    • pp.3-14
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    • 1995
  • To investigate the effect of illumination conditions on visual inspection performance for TV panel glasses, three dependent variables, inspection time, error, and preference , were measured and analyzed through two consecutive experiments. The first experiment for reflection inspection was conducted using two independent variables, position and brightness. The second experiment for transparent inspection was made using two independent variables, height and brightness. The summary of the results of the experiment for reflection inspection are as follows ; The inspection performance of the position right above the subject (Position 1) was the best among the conditions in terms of errors, while the performance of the position slightly in front of and above the subject(Position 2) was the best in terms of inspection times. Inspection time was statistically different according to the brightness conditions specifically at the position in front of the subject(Position 3). The results of the second experimen for transparent inspection are that the inspection performance at medium height (Height 2) was the best among the three conditions in terms of errors while the performance at lower height(Height 3) was the best in subject preference. Based upon both results with respect to actual field conditions, two alternative inspection station designs were proposed for each lighting conditon.

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Alternative Scheme of INS-Dependent Positioning for Relative Navigation without GRUs (GRU 부재 상대항법에서의 INS 의존 측위 대체 방안)

  • Kim, Ki-hyoung;Lee, Kyu-man;Lim, Jae-sung
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.40 no.12
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    • pp.2520-2527
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    • 2015
  • Position information is important to carry out military operations. In general, GPS is used to estimate position. However, GPS is vulnerable to jamming due to the low received signal strength, therefore GPS can be easily jammed. The relative navigation is an auxiliary navigation system defined in JTIDS. When GPS is jammed, the relative navigation requires ground reference units on the ground to operate accurately. If the ground reference unit does not exist, nodes operated by the relative navigation depend on the inertial navigation system to identify their position. However, this positioning scheme based on only INS causes accumulative position error, therefore the nodes cannot identify their position accurately for a long time. In this paper, we propose an alternative to reduce position error generated by depending inertial navigation system. In order to verify that the performance of proposed scheme is better than that of the existing scheme, various simulations are conducted.

A Study on Implementable Sun Tracking Algorithm for Mobile Systems (이동형 시스템에 구현이 가능한 태양 추적 시스템에 관한 연구)

  • Choi, Ju-Yeop;Choy, Ick;Song, Seung-Ho;An, Jin-Ung;Lee, Dong-Ha
    • Journal of Institute of Control, Robotics and Systems
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    • v.15 no.12
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    • pp.1169-1174
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    • 2009
  • In this paper, a prototype of implementable Sun tracking algorithm for mobile systems powered by alternative energy is proposed. The proposed system uses 2-axis tilt sensor and 3-axis magnetic sensor to measure orientation and posture of the system according to the horizon coordinates system, which are used to compensate tilt effects. Then through astronomical calculation using the present time and position informations obtained from GPS sensors, the calculated azimuth and altitude of the Sun in that location. The position of the Sun is converted to that of the mobile Sun tracking system coordinates and used to control A-axis and C-axis of the system.

An alternative portable dynamic positioning system on a barge in short-crested waves using the fuzzy control

  • Fang, Ming-Chung;Lee, Zi-Yi
    • Ocean Systems Engineering
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    • v.5 no.3
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    • pp.199-220
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    • 2015
  • The paper described the nonlinear dynamic motion behavior of a barge equipped with the portable outboard Dynamic Positioning(DP) control system in short-crested waves. The DP system based on the fuzzy theory is applied to control the thrusters to optimally adjust the ship position and heading in waves. In addition to the short-crested waves, the current, wind and nonlinear drifting force are also included in the calculations. The time domain simulations for the six degrees of freedom motions of the barge with the DP system are solved by the $4^{th}$ order Runge-Kutta method. The results show that the position and heading deviations are limited within acceptable ranges based on the present control method. When the dynamic positioning missions are needed, the technique of the alternative portable DP system developed here can serve as a practical tool to assist those ships without equipping with the DP facility.

Occipital Alopecia Following Open Heart Surgery -One case report- (개심술후 후두부에 발생한 국소탈모증 -1례 보고-)

  • 김찬용
    • Journal of Chest Surgery
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    • v.12 no.3
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    • pp.259-262
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    • 1979
  • Alopecia is a minor complication following open heart surgery, but it is a cosmetic and psychotic problem to the patient. Especially the extensive long period of operation, prolonged mechanical ventilation and no change of patient head position during operative and recovery period may serve the localized scalp pressure effect, which causes postoperative alopecia. So, for prevention of the postoperative alopecia, adequate blood flow and pressure must be maintained with alternative change of head position during operative and recovery period. The author experienced one case of occipital alopecia following open heart surgery and reports with literature.

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Magnetic Substance Search Using Finite Element Method and Neural Network (유한요소법과 인공지능을 이용할 자성체 탐사)

  • Lee, Kang-Woo;Park, Il-Han
    • Proceedings of the KIEE Conference
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    • 1997.07a
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    • pp.198-200
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    • 1997
  • This paper consider a simple Nondestructive Testing(NDT) having eddy currnt effect. We analyzed the two dimension modeling of alternative magnetic field. eddy current with voltage source. And, the current magnitude and phase data obtained from each different frequency five object position is used for learning the neural network. Therefore, we can recognize an object position pattern from new input current magnitude, phase data.

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