• Proceedings of the Korean Information Science Society Conference
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• 2006.10c
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• pp.83-87
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• 2006

Similarity search in moving object trajectories is an active area of research. In this paper, we introduce a new concept of measure that computes spatial distance (similarity) between two trajectories of moving objects on road networks. In addition, we propose an algorithm that generates a sequence of matching edge pairs for two trajectories that ate to be compared and computes spatial distance between them which is non Euclidian in nature. With an example, we explain how our algorithm works to show spatial similarity between trajectories of moving objects in spatial network.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.591_592
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• 2009

For a similar price signal to local consumer, a regional clustering is important that can transfer a equal sign to the bus which has each different price on the basis of bus. If you take LMP and local information this method into consideration at the same time, and you give weight on neither one side, buses on a borderline can move on arbitrary. For solving this problem, in this paper will propose a clustering method to have applied new concept called 'electric distance'.

• Journal of Ocean Engineering and Technology
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• v.24 no.1
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• pp.133-139
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• 2010

From the ancient times, there are waves in the ocean. And all the moving body have energy. We have a kind of hope to convert the wave energy into electric one. Finally we can find out a power generator mechanism that mainly use the principle of pulleys. We have made drawings for this and completed the wave energy converter. This wave energy converter consists of several pulleys, rope, generator, buoys and anchors. The distance between an anchor and buoy is changed according to the hight of waves. Several sets of anchors, pulleys and buoys can make the movement of rope, and the ropes wind up a converter axis. In case of 1 meter movement of the buoy, the winding distance will be amplified 2 or 3 times if we use several moving and fixed pulleys. Based on this concept, we developed 2 kind of prototypes. One is for the test in the laboratory and the other is for the field test. Through the two test, we could confirm the usability of this mechanism.

• Proceedings of the KIEE Conference
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• 2000.11a
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• pp.174-176
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• 2000

In this paper, a high speed distance relay, using a digital signal processor(DSP) is presented. The idea of the protective algorithm is based on the least square method using minimum data window to minimize the relay operating time. A new disign concept for a low-pass filter is proposed. This analog low pass filter has minimum transient response time. The main processor of the relay is TMS320C31. According to a series of real time tests, the proposed protective relay shows reliable and fast operating characteristics.

• Journal of Biosystems Engineering
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• v.25 no.2
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• pp.141-150
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• 2000

This study was carried out to de develop a control strategy of a fruit harvesting redundant robot. The method of generating a safe trajectory, which avoids collisions with obstracles such as branches or immature fruits, in the 3D(3-dimension) space using artificial potential field technique and virtual plane concept was proposed. Also, the method of setting reference velocity vectors to follow the trajectory and to avoid obstacles in the 3D space was proposed. Developed methods were verified with computer simulations and with actual robot tests. Fro the actual robot tests, a machine vision system was used for detecting fruits and obstacles, Results showed that developed control method could reduce the occurrences of the robot manipulator located in the possible collision distance. with 10 virtual obstacles generated randomly in the 3 D space, maximum rates of the occurrences of the robot manipulator located in the possible collision distance, 0.03 m, from the obstacles were 8 % with 5 degree of freedom (DOF), 8 % with 6-DOF, and 4% with 7-DOF, respectively.

• The Journal of Korea Robotics Society
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• v.4 no.3
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• pp.218-224
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• 2009

We propose a formation-keeping and changing methods for outdoor multiple mobile robots in chained form. Our proposed method is designed to maintain the follower to its desired distance and orientation with respect to the pole using the concept of virtual force such as potential field. The client robots use a behavior-based control to perform kinematic control to keep formation under the centralized system in our software framework. The relationship of each poles that is expressed by set of distance and angle is the description of the formation type and the type converting is performed using this set. In addition, we also examine the stability and capability in the simulation and experiments with real robots.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.18 no.4
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• pp.417-422
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• 2009

The injection mold cooling circuit optimization was studied with a response surface method in the previous research. It took so much time to find an optimum solution for a large product due to an extensive amount of calculation time for the CAE analysis. In order to use the optimization technique in the actual design process, the calculation time should be much reduced. In this study, we tried to reduce the number of design variables with the concept of the close relationship between the depth and the distance of cooling channel. The optimum ratio of the distance to the depth of cooling channels for a 2-dimensional problem was 2.0 so that the optimum ratio was again sought out for 4 large automotive parts. Therefore, the number of design variables for the cooling circuit optimization can be reduced in half, resulting in much faster running time for the optimization as a design tool.

• English Language & Literature Teaching
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• v.13 no.2
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• pp.155-176
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• 2007

An attempt to investigate the effect of gender differences on Korean students' EFL learning orientation was made. To explain a Korean EFL learning context, three criteria (cultural distance between the target country and the host country, communicative needs of the TL, the status of the TL in the host country) are adopted. Moreover, as a contrastive FL learning context from the Imposed FL learning context, a FL learning context where there is a substantial cultural distance from the TL community, communication needs of the TL do not exist, and the TL enjoys a special educational and socioeconomic status in the host country, a concept of an Integrative FL learning context is newly brought up in this paper. As the result of a questionnaire conducted in four different high schools, female learners can be claimed to be more internalized about academic and socioeconomic benefits the TL entails for their social advancement and overcoming inequality between men and women in society, albeit insignificant numerical data.

• Journal of the Korea Society of Computer and Information
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• v.20 no.11
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• pp.63-68
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• 2015

In this paper, we propose a new energy efficient scheme which can prolong the life of sensor networks, it should be able to reduce the number of sensing. We use the concept of safe zone for manage the appropriate range of properties. We measure the distance between the sensed temperature value and the center of the zone, and calculate the next sensing interval based on this distance. We name our proposed scheme "VIS". To assess the performance of the proposed scheme the actual temperature data was collected using the sensor node. The algorithm was implemented through the programming and was evaluated in a variety of settings. Experimental results show that the proposed algorithm is to significantly reduce the number of sensing in terms of energy efficiency while having the ability to know the state of the sensor nodes periodically. Our VIS algorithm can be useful in applications which will require the ability of control to the temperature within a proper range.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.4
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• pp.795-802
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• 2007

In the future combat fields, US department of defense (DoD) pursuits the enhancement of the synergy effects of the force through the networking. In specially, the US army force has been emphasized the information superiority for the knowledge superiority and decision superiority of the collaboration force in the Joint Vision 2020, when the operations is performed in the battle fields. In this case study, we are reviewed about the concept of network centric operation and operation case in the centering around the US and analyzed the quantitative distance and effect, performance of communication relay about the distance of mission operation.