• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.408-410
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• 2003

In this paper, an improved gradient direction assisted linking algorithm is proposed. This algorithm begins with initial seeds satisfying some local criteria. Then it will search along the direction provided by the initial point. A window will be generated in the gradient direction of the current point. Instead of the conventional method which only considers the value of the local salient structure, an improved mathematical model is proposed to describe the desired linear features. This model not only considers the value of the salient structure but also the direction of it. Furthermore, the linking problem under this model can be efficiently solved by dynamic programming method. This algorithm is tested for linear features detection in IKONOS images. The result demonstrates this algorithm is quite promising.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.10
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• pp.4908-4922
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• 2019

The popularization of smartphones in recent years has created a rich ground for online-to-offline (O2O) services based on location information. In the process of finding user locations in O2O services, BLE (Bluetooth Low Energy) beacons are widely used because the beacons are economical in many ways. The current BLE method does not specify the direction of user movement, but adding that information could enrich the user experience for various O2O services. This paper proposes a method that identifies the user movement direction through data analysis on data sets generated by a pair of BLE beacons. Also we demonstrate its implementation with examples of services that need the direction information of users in order to show the feasibility of the method proposed.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.05a
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• pp.50-54
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• 2003

The output characteristics of thin film NiO/NiFe bilayered magnetoresistive device have been measured as a function of the direction of external magnetic field. Each layer was fabricated by rf magnetron sputtering method, and especially, the under layer, NiO, was fabricated under the in-situmagnetic field of about 1000Oe. The magnetoresistive devices were designed with the angle of 45degree between the direction of current of the device pattern and the induces magnetic field in the NiO film layer. The output of the devices had a good linearity when the devices were placed on the external magnetic field perpendicular to induced field direction and also 45 degree with the currenr path direction.

• IEMEK Journal of Embedded Systems and Applications
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• v.10 no.5
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• pp.317-324
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• 2015

In his paper, we propose the graphic-based direction tracking system that be able to detect the current location and direction of the flight object and virtually run the pointing to the flight direction when a small UAV is located in the occlusion area behind buildings or obstacles in the moving surveillance systems. Based on the experimental results about the simulation flight path extracted from the Mission Planner we found the proposed system operates the desired flight mission effectively in tracking.

• Journal of Korea Water Resources Association
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• v.46 no.2
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• pp.205-218
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• 2013

The likelihood of rip current at Haeundae beach according to wave parameters, such as wave height, period, direction, and tidal elevation, was estimated by using numerical simulations with a Boussinesq model, FUNWAVE. To examine the estimation, the rip current occurred on 12th June, 2011 at Haeundae beach was simulated based on observations. For the estimation, the following procedure was carried out. First, extensive numerical simulations of nearshore circulations are performed under various random sea conditions according to the wave parameters. Second, from the numerical results, cross shore components of two-wave-period averaged velocities over the nearshore area were computed, and their seawardly maximum was defined as rip current velocity of the area. Third, using time series of the rip current velocity, we computed the ratio of the simulation time and the time period in which the rip current velocity exceed a threshold velocity for rip-current accidents, and thus the ratio was quantified as the likelihood of rip current at Haeundae beach for the input wave parameters. From the resultant estimations, it was found that the rip current likelihood increases as wave height and period increase, and tidal elevation decreases.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.38 no.1
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• pp.69-78
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• 2002

In order to examine the directional suitability of the axis direction of the fishing gear against the current, the experiments were carried out at the bamboo weir in Samchunpo water area from January, 2000 to September, 2001 The results of the study are as follows: In the experimental fishing gear constructed in the "V" shape, the range between two reference piles located at the entrance was 2.5m. The direction of bamboo weir′s axis was 355.5$^{\circ}$ The length of the left wing and those from the reference pile to the starting point of a curve were 106.0m, 7.5m, respectively. The length of the right wing and those from the reference pile to the starting point of a curve were 79.0m, 10.0m, respectively. Depths around the left and right stone wall that drove the steel pile were 5.0~6.5m and 6.5~9.5m, respectively. Also, depths on the bamboo weir′s axis and around the sack were 7.0~8.0m and about 8.0m, respectively. The maximum height of stone walls at the point of the left wing, the right wing and around the sack on the bamboo weir\` axis were 3.0m, 4.7m and 4.0m, respectively, Widths of stone walls at the point of both of the wings and around the sack on the bamboo weir\`s axis were 10.0~l4.0m, 22.0~25.0m, respectively. The averaging current direction on ebb tide was measured two times and it was 169.2$^{\circ}$ but the direction had about a 6.3$^{\circ}$ difference from the bamboo weirs axis. The maximum current speed appeared two to three hours later from the time of high tide and the current speed over 80.0cm/s lasted during about two Hours on the ebb tide In the case of a straight type wing In the bamboo weir, the eddy out of the left wing was comparatively big and the current on the right side from the bamboo weir′s axis had a tendency in turning to the right wing side. But in the case of a curve type wing, the eddy and tendency reduced significantly. It was thought that the experimental fishing gear was set suitably from the result of this simulation.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.32 no.1
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• pp.39-47
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• 2020

In order to investigate current characteristics at the Gungpyung beach, which is a macrotidal flat, field measurements were carried out in the summer and winter at the intertidal and the subtidal zones. The distribution of residual current at intertidal flat was dominant in the northward direction in the summer and dominant in the northward and southwestern directions in the winter. The direction and speed of the residual current in the winter are highly correlated with the significant wave height, and the turbidity is also highly correlated with the significant wave height. Therefore, in the winter, high sediment rates are suspended by high waves, and sediments are transporting due to the residual current in the southwest direction. On the other hand, it is expected that the northward residual current is predominant due to the small wave in the summer, and sediment transport does not occur largely due to less suspended sediments. In addition, sediment transport in the southern direction is blocked by the dock, which is the artificial structure, and the erosion occurs in the south side of the dock. The erosion pattern in the macrotidal zone of Yellow sea is dominated by seasonal waves, and blocking of sediments by artificial structure is very important.

• Progress in Superconductivity and Cryogenics
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• v.16 no.2
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• pp.42-46
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• 2014

In this study we investigated ac transport current losses in the face to face stack for the anti-parallel current flow, and compared the electromagnetic properties with those of the single SC tape as well as those of the same stack for the parallel current path. The gap between the SC tapes in the stack varied in order to verify the electromagnetic influence of the neighbors when current flows in opposite direction, and the model was implemented in the finite element method program by the commercial software, COMSOL Multiphysics 4.2a. Conclusively speaking, the loss was remarkably decreased for the anti-parallel current case, which is attributed the magnetic flux compensation between the SC layers due to the opposite direction of the current flows. As the gap between SC tapes was increased, the loss mitigation became less effective. Besides, the current density distribution is very flat cross the sample width for the narrower gap case, which is believed to be benefit for the power electric system. These results are all in good agreement with those predicted theoretically for an infinite bifilar stack.

• 대한두경부종양학회:학술대회논문집
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• 2005.11a
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• pp.232-232
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• 2005

• Magazine of the Korea Concrete Institute
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• v.22 no.2
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• pp.26-28
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• 2010