• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11b
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• pp.178-187
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• 2000

The tillage operation by rotary implements is widely done in Korea. In the case of rotary implements, the tillage depth control system is one of important implement control systems. A contact type-sensor for measurement of the ground height was designed and fabricated to evaluate the possibility of application of the sensor on the tillage depth control system. Indoor experiments were conducted to obtain static and dynamic detection characteristics of the sensor under various conditions; 1) several moisture contents for four soil samples, 2) two soil surfaces with a designed configuration, 3) four heights of the sensor from the soil surface, 4) five traveling speeds of the carrier on which the sensor was attached, and so on. The experimental results showed the detection characteristics of the sensor sufficient as the ground height sensor of the tillage depth control system.

• Nuclear Engineering and Technology
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• v.46 no.4
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• pp.489-500
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• 2014

In this study, remote handling strategies for a large-scale argon cell facility were considered. The suggested strategies were evaluated by several types of field test. The teleoperation tasks were performed using a developed remote handling system, which enabled traveling over entire cell area using a bridge transport system. Each arm of the system had six DOFs (degrees of freedom), and the bridge transport system had four DOFs. However, despite the dexterous manipulators and redundant monitoring system, many operators, including professionals, experienced difficulties in operating the remote handling system. This was because of the lack of a strategy for handling the installed camera system, and the difficulty in recognizing the gripper pose, which might fall outside the FOV (field of vision) of the system during teleoperation. Hence, in this paper, several considerations for the remote handling tasks performed in the target facility were discussed, and the tasks were analyzed based on ergonomic factors such as the workload. Toward the development of a successful operation strategy, several ergonomic issues, such as active/passive view of the remote handling system, eye/hand alignment, and FOV were considered. Furthermore, using the method for classifying remote handling tasks, several unit tasks were defined and evaluated.

• Korean Journal of Agricultural Science
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• v.37 no.1
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• pp.123-130
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• 2010

A steering control system based on CAN(Controller Area Network) for autonomous tractor was developed to reduce duty of a central processing computer and to improve performance of steering control in terms of reduced control interval and error. The steering control system consisted of a SCU (Steering Control Unit), an EHPS system, and a potentiometer. The SCU consisted of an MCU (Micro Controller unit), an A/D converter, and a DC-DC converter, and a PID controller was used to control steering angle. The steering control system was communicated with the computer by CAN-bus. Each actuator and implement was connected to a multi-function board interfacing with the computer through a USB cable. Without CAN, control interval of the autonomous tractor was 1.5 seconds. When the CAN-based steering control system was combined with the autonomous tractor, however, control interval of the integrated system was reduced to those less than 0.05 seconds. When the autonomous tractor was operated with 1.5-s and 0.05-s control cycles at a 0.63-m/s travelling speed, the trajectories were close to straight lines for both of the control cycles. For a 1.34-m/s traveling speed, tractor trajectory was close to sine wave with a 1.5-s control cycle, but was straight line with a 0.05-s control cycle.

• Journal of Information Technology Services
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• v.20 no.5
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• pp.29-41
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• 2021

The spread of COVID-19 has been changed the tourism industry. Travelers changed their traveling style and started to consider congestion of the spot for their health and safety. In Jeju, a famous tourist destination in South Korea, managing the congestion of tourists has become an important issue. This example introduces the Jeju Tourism Organization's development of a system as a smart tourism information service that manages congestion in real-time big data. Combining with congestion theory and behavior immune system, we would like to assure the necessity of the system. Also, by analyzing the system, we understand how deducing congestion information from big data and the new paradigm of the tourism industry combined with congestion theory. Data was collected by Korea's telecommunication company SKT to develop the system. The paper explains the reason for choosing the company and the pros of data quality. We expect this system to be a solution for any other city in the world under a similar situation. Finally, several suggestions for the system are included to promote and better future usage.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.24 no.1
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• pp.79-85
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• 2011

Bridge Weigh-in-Motion(BWIM) system calculates a travelling vehicle's weight without interruption of traffic flow by analyzing the signals that are acquired from various sensors installed in the bridge. BWIM system or data accumulated from the BWIM system can be utilized to development of updated live load model for highway bridge design, fatigue load model for estimation of remaining life of bridges, etc. Field test with moving trucks including various load cases should be performed to guarantee successful development of precise BWIM system. In this paper, a numerical simulation technique is adopted as an alternative or supplement to the vehicle traveling test that is indispensible but expensive in time and budget. The constructed numerical model is validated by comparison experimentally measured signal with numerically generated signal. Also vehicles with various dynamic characteristics and travelling conditions are considered in numerical simulation to investigate the variation of bridge responses. Considered parameters in the numerical study are vehicle velocity, natural frequency of the vehicle, height of entry bump, and lateral position of the vehicle. By analyzing the results, it is revealed that the lateral position and natural frequency of the vehicle should be considered to increase precision of developing BWIM system. Since generation of vehicle travelling signal by the numerical simulation technique costs much less than field test, a large number of test parameters can effectively be considered to validate the developed BWIM algorithm. Also, when artificial neural network technique is applied, voluminous data set required for training and testing of the neural network can be prepared by numerical generation. Consequently, proposed numerical simulation technique may contribute to improve precision and performance of BWIM systems.

• Proceedings of the KSR Conference
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• 2011.05a
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• pp.1563-1571
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• 2011

In the commercial trains, there are monitors hung on the ceiling which simply display broadcasted contents so a passenger in a cabin has only one choice of passively watching them or not. To lead the application of IT in railway, keep a passenger from tedious journey, or help a passenger having a productive time, an MCS(Multimedia Contents System) was analyzed, designed, and implemented. A passenger can select and use a content from a smart terminal that is attached at the passenger's seat. A smart terminal is one that has its own memory and processor to handle informations and interact with a user. In this paper, the contents, such as train schedule, transfer information, traveling information, e-book, TV, music, and game, that the MCS can provide were introduced. To validate the applicability of the MCS on a next generation high-speed train, a testing environment will be set on a pre-production car and tested. The successful installation of the MCS will boost up the competitive power of the next generation train in the world market.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.2524-2528
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• 2003

High-precision position system is widely used in lots of fields such as semiconductor industry, biotechnology, display and other up-to-date industry field. One of the main issues is to have a long traveling range with precision. There are a few solutions. For instance, there are inchworm methods, lever principle. In this study, we use lever principle to amplify output displacement with a new mechanical amplification structure. We designed new type 3DOF stage with PZT actuator and capacitive sensor. Non-monolithic structure is suggested to obtain the convenience of assembly and modification. Driving parts are designed as modules that generate displacement amplification of each axis. Designed motion module consists of 3 flexure hinges and a PZT actuator with double L lever structure.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.3 no.1 s.4
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• pp.21-30
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• 2004

This paper describes the design of RF link between RSE and OBU of ETCS and the analysis of the antenna beam pattern to get a proper communication area in the cross direction and traveling direction of lanes. This stage should be performed prior to determination of system requirements of ITS service based on active DSRC. This study is important and fundamental technical analysis to design and implement base station of ETCS.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2003.09a
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• pp.346-349
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• 2003

For a traveling crane, various control methods such as neural network predictive control and TDOFPID(Two Degree of Freedom Proportional Integral Derivative) are studied. So in this paper, we proposed improved navigation method to reduce transfer time and sway with anti-collision path for avoiding collision in its movement to the finial coordinate. And we constructed the NNPPID(Neural Network Predictive PID) controller to control the precise move and speedy navigation. The proposed predictive control system is composed of the neural network predictor, TDOFPID controller, and neural network self-tuner. We analyzed ASC(Automated Stacking Crane) system and showed some computer simulations to prove excellence of the proposed controller than other conventional controllers.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2002.11a
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• pp.281-286
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• 2002

An existent hoist drive system is using each different drive equipment in control of Hoisting, traveling(T/L), traversing(T/S) driving, so there are much energy losses because of excessive weight. Also, power circuits are using relay contact, so working environment are frequent secession accident etc.. by shock on unfavorable condition, and there is danger of safety accident, maintenance has frequent problem and so on. To solve these problem, it is integrated each driving power supply in drive system for hoist control and drive, utility power supply etc.. by single device in this research. The power circuit is consisted of non-contact circuit applying to bidirectional voltage controller circuit using thyristor that is power semiconductor switching device