• The Journal of Engineering Geology
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• v.17 no.4
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• pp.615-621
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• 2007

Seismic refraction survey which is assumed to be effective for investigating of the amount of bed sediment was applied to two sites having different soil types. The ten lines of seismic surveys were carried out in the areas of the levee near the Wolchon Bridge, Yongin and the Damam levee, Yecheon. At the same time, two borehole data were obtained to be used in classifying geological formations on the inverted seismic sections. As the results of interpolating the depths of geological formations and the surface elevation values, it is possible to estimate the volume of the bed sediments at $24,000m^3\;and\;56,000m^3$ in Yongin and Yecheon, respectively.

• Korean Journal of Computational Design and Engineering
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• v.13 no.2
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• pp.77-88
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• 2008

Nowadays personal users create a variety of multi-media contents and share them with others through various devices over the Internet since the concept of user created content (UCC) has been widely accepted as a new paradigm in today's multi-media market, which has broken the boundary of contents providers and consumers. This paradigm shift has also introduced a new business model that makes it possible for them to create their own multi-media contents for commercial purpose. This paper proposes a tangible virtual studio using augmented reality to author multi-media contents easily and intuitively for personal broadcasting and personal content generation. It provides a set of tangible interfaces and devices such as visual markers, cameras, movable and rotatable arms carrying cameras, and miniaturized set. They can offer an easy-to-use interface in an immersive environment and an easy switching mechanism between tangible environment and virtual environment. This paper also discusses how to remove inconsistency between real objects and virtual objects during the AR-enabled visualization with a context-adaptable tracking method. The context-adaptable tracking method not only adjusts the locations of invisible markers by interpolating the locations of existing reference markers, but also removes a jumping effect of movable virtual objects when their references are changed from one marker to another.

• Korean Journal of Agricultural and Forest Meteorology
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• v.6 no.3
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• pp.164-169
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• 2004

A spatial interpolation scheme incorporating local geographic potential for cold air accumulation (TOPSIM) was used to test the feasibility of operational frost warning in Chatancheon basin in Yeoncheon County, where the introduction of new crops including temperate zone fruits is planned. Air temperature from April to June 2003 was measured at one-minute intervals at four locations within the basin. Cold-air accumulation potentials (CAP) at 4 sites were calculated for 3 different catchment scales: a rectangular area of 65 x 55 km which covers the whole county, the KOWACO (Korea Water Corporation) hydrologic unit which includes all 4 sites, and the sub-basins delineated by a stream network analysis of the digital elevation model. Daily minimum temperatures at 4 sites were calculated by interpolating the perfect prognosis (i.e., synoptic observations at KMA Dongducheon station) based on TOPSIM with 3 different CAPs. Mean error, mean absolute error, and root mean square error were calculated for 45 days with no precipitation to test the model performance. For the 3 flat locations, little difference was detected in model performance among 3 catchment areas, but the best performance was found with the CAPs calculated for sub-basins at one site (Oksan) on complex terrain. When TOPSIM loaded with sub-basin CAPs was applied to Oksan to predict frost events during the fruit flowering period in 2004, the goodness of fit was sufficient for making an operational frost warning system for mountainous areas.

• Journal of Institute of Control, Robotics and Systems
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• v.17 no.4
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• pp.321-327
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• 2011

This paper proposes an equipment and an algorithm for modeling the magnetic force of electromagnets in magnetic levitation systems. We assume that the magnetic force model is represented in terms of a 2D lookup table. The 2D lookup table is constructed by applying noncausal filtering and interpolation to data measured by the proposed modeling equipment. The proposed modeling equipment is designed such that it can measure the magnetic force exerted on the levitation object while it changes the voltage applied to the electromagnet and position of the levitation object. The algorithm of making a 2D lookup table has two stages. The data measured by the proposed modeling equipment is smoothed by a noncausal filter and then the 2D lookup table is obtained by interpolating filtered data. The proposed modeling method has advantages of time-saving, model consistency, and chance of automation for mass production. We show the validity of proposed method through control experiments.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2014.10a
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• pp.114-116
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• 2014

The interpolation of the missing AIS dynamic data can be used for predicting the lost data of the ship's state which is able to product the valuable information for analyzing and investigating the maritime accidents. The previous research proposed some interpolating methods however there exists some problem, firstly, the interpolated parameters such as COG, SOG, HDG weren't described sufficiently and accurately as in AIS message, secondly, each method is only suitable to some kinds of given AIS data, finally at heavy wind and current area, the parameters of AIS dynamic change quickly in short time, therefore, the modelling of the variation of ship's dynamic based on the physical characteristic is very difficult, in these cases the time-series and numerical method are usually better. This research proposes the other method through numerical analysis which can be suitable for many different kinds of the lost data, parameters are interpolated sufficiently, beside that this model is appropriate to all variation in short time interval. All the given AIS dynamic are regarded as the functions to time, then curves are established for fitting all data. Experiments are carried out to evaluate the performance of this approach, the interpolation results show this approach can be applied well in practice.

• Geomechanics and Engineering
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• v.9 no.3
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• pp.275-286
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• 2015

A new method is presented to recover missing deformation data of lateral walls of foundation pit when the monitoring is interrupted; the method is called Dynamic Mathematical Model - Parameter Interpolation. The deformation of lateral walls of foundation pit is mainly affected by the type of supporting structure and the situation of constraints, therefore, this paper mainly studies the two different kinds of variation law of deep horizontal displacement when the lateral walls are constrained or not, proposes two dynamic curve models of normal distribution type and logarithmic type, deals with model parameters by interpolating and obtains the parameters of missing data, then missing monitoring data could be Figured out by these parameters. Compared with the result from the common average method which is used to recover missing data, in the upper 2/3 of the inclinometer tube, the result by using this method is closer to the actual monitoring data, in the lower 1/3 part of the inclinometer tube, the result from the common average method is closer to the actual monitoring data.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.3B
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• pp.541-548
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• 2000

In the MPEG-4 standardization phase, many methods for coding the irregular shaped VOP (video object Plane) have been researched. Texture coding is one of interesting research items in the MPEG-4. There are the Low pass extrapolation (LPE) padding, the shape adaptive DCT (SA-DCT), and the Extension-Interpolation (EI)/2D-DCT proposed in [1] as texture coding methods. the EI/2D-DCT is the method extending and interpolating luminance values from and Arbitrarily Shaped (AS) image segment into an 8 x 8 block and transforming the extended and interpolated luminance values by the 8x8 DCT. although the EI/2D-DCT and the SA-DCT work well in coding the As image segments. they are degraded since they use one-dimensional (1-D) methods such as the 1D-EI and the 1D-DCT in the two-dimensional (2-D) space. in this paper, we analyze the performance of the EI/2D-DCTand propose a new non-symmetric sig-sag scanning method, which non-symmetrically scans the quantized coefficients in the DCT domain to improve the EI/2D-DCT.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.48 no.8
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• pp.951-957
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• 1999

The saddle node bifurcation (SNB) and the distance voltage instability are valuable information in power system planning and operation. This paper presents a new efficient, robust and unified strategy to compute the SNB by the combined use of the continuation power flow (CPF), Point of Collapse (PoC) method, and the method of a pair of multiple load flow solutions (PMLFS) with Lagrange interpolation utilizing only their advantages: the approximate nose curves and critical loading are determined fast by Lagrange-interpolating two stable and two unstable solutions obtained by using the robust CPF and PMLFS; the exact SNB is computed by the quadratically converging PoC method. The proposed method has been tested on Klos-Kerner 11-bus, New England 30-bus, IEEE 118-bus and KEPCO 791-bus systems. The method is found to be so efficient that computation time for determining the SNB of the KEPCO 791-bus system is 17.82 sec by a notebook PC with 300 MHz Pentium processor.

• Journal of Sensor Science and Technology
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• v.10 no.1
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• pp.24-32
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• 2001

High temperature platinum resistance thermometers(HTPRTs) were designed and fabricated using a synthetic sapphire single crystal as sensor former, insulation and protection tube, and its characteristics was investigated. Several fixed points measurement showed that the sapphire HTPRTs were satisfied with the ITS-90 criteria as the interpolating thermometer. The temperature-resistance characteristics of HTPRT was fitted to the quadratic relationship in the temperature range from $500^{\circ}C$ to $1500^{\circ}C$. The reproducibility of Cu freezing point realized using the sapphire HTPRT was ${\pm}19.2\;mK$. The insulation resistance of the HTPRT exponentially decreased as temperature increased, and showed to $63\;k{\Omega}({\sim}31.5\;mK)$ at $1500^{\circ}C$.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.10 no.1
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• pp.37-44
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• 1998

In this study a new hybrid method is developed for solving flow-dominated transport problems accurately and effectively. The method takes the forward-tracking particle method for advection. However, differently from the random-walk Lagrangian approach it solves the diffusion process on the fixed Eulerian grids. Therefore, neither any interpolating algorithm nor a large enough number of particles is required. The method was successfully examined for both cases of instantaneous and continuous sources released at a point. Comparison with a surrounding 5-point Hermite polynomial method (Eulerian-Lagrangian method) and the random-walk pure Lagrangian method shows that the present method is superior in result accuracy and time-saving ability.