• Korean Journal of Remote Sensing
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• v.15 no.4
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• pp.297-305
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• 1999

Ocean Scanning Multispectral Imager (OSMI) is a payload on the KOMPSAT satellite to perform global ocean color monitoring for the study of biological oceanography. The instrument images the ocean surface using a wisk-broom motion with a swath width of 800km and a ground sample distance (GSD) of < 1km over the entire field of view (FOV). The instrument is designed to have an on-orbit operation duty cycle of 20% over the mission lifetime of 3 years with the functions of programmable gain/offset and on-board image data compression/storage. The instrument also performs sun and dark calibration for on-board instrument calibration. The OSMI instrument is a multi-spectral imager covering the spectral range from 400nm to 900nm using CCD Focal Plane Array (FPA). The ocean colors are monitored using 6 spectral channels that can be selected via ground commands. KOMPSAT satellite with OSMI was integrated and the satellite level environment tests including instrument aliveness/functional test, such as launch environment, on-orbit environment (Thermal/Vacuum) and EMI/EMC test were performed at KARl. Test results met the requirements and the OSMI data were collected and analyzed during each test phase. The instrument is launched on the KOMPSAT satellite on December 21,1999 and is scheduled to start collecting ocean color data in the early 2000 upon completion of on-orbit instrument checkout.

• Proceedings of the KSRS Conference
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• 1999.11a
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• pp.375-380
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• 1999

Ocean Scanning Multispectral Imager (OSMI) is a payload on the KOMPSAT satellite to perform worldwide ocean color monitoring for the study of biological oceanography. The instrument images the ocean surface using a wisk-broom motion with a swath width of 800 km and a ground sample distance (GSD) of<1km over the entire field of view (FOV). The instrument is designed to have an on-orbit operation duty cycle of 20% over the mission lifetime of 3 years with the functions of programmable gain/offset and on-board image data compression/storage. The instrument also performs sun and dark calibration for on-board instrument calibration. The OSMI instrument is a multi-spectral imager covering the spectral range from 400nm to 900nm using CCD Focal Plane Array (FPA). The ocean colors are monitored using 6 spectral channels that can be selected via ground commands. KOMPSAT satellite with OSMI was integrated and the satellite level environment tests and instrument aliveness/functional test as well, such as launch environment, on-orbit environment (Thermal/vacuum) and EMl/EMC test were performed at KARI. Test results met the requirements and the OSMI data were collected and analyzed during each test phase. The instrument is launched on the KOMPSAT satellite in the late 1999 and the image is scheduled to start collecting ocean color data in the early 2000 upon completion of on-orbit instrument checkout.

• Journal of the Korean Geophysical Society
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• v.8 no.3
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• pp.109-113
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• 2005

The ground-motion (GM) attenuation relations available in Korea has required the validation process for large earthquakes since most of them were developed based on small earthquake database. The Fukuoka earthquake (M=7.0) that occurred near the Korean Peninsula provides invaluable data to indirectly evaluate the attenuation characteristics of the strong GM in Korea. The GM levels (PGA, SA) obtained from the KIK-net downhole stations near the epicenter (R<100km) are reasonably predicted by the GM attenuation relation developed by KEPRI in 2003 for the Kori NPP site, the result of which validates the use of KEPRI GM attenuation relation for predicting GM induced by future large earthquakes. Also, the comparison between the Osaki spectra and response spectra of KIK-net downhole data reveals that the amplitude levels of Osaki spectra are higher than the spectra from KIK-net stations which are believed to be installed at the seismic basement.

• Journal of Ocean Engineering and Technology
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• v.21 no.4
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• pp.55-60
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• 2007

In contrast to the method in Part I, which is considered to be the general approach, Part II pursues a closed-form solution. However, this closed-form solution is available only in the 2D situation under the assumption that the moving object is restricted to a 2D space, and also requires the use of only two laser-slit sensors. Since the motion of the container loaded on top of an AGV is restricted to a plane parallel to the ground, it can be considered a 2D motion. As a simple method, but with a high cost, the use of a laser scanner is also discussed. Since the approach in Part I already uses three laser-slit sensors, it is desirable to use the schemes presented in Part II for supplementary purposes.

• Journal of Environmental Science International
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• v.7 no.3
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• pp.349-360
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• 1998

Effects of uniform flow on a two-dimensional mesoscale horizontal convection were investigated by using the vorticity and thermodynamic equations. For thins purpose, We simulated properties of a thermal convection m a stably stratified Boussinesq flued caused by partial heating at the center of a lower boundary If we don't consider effects of the uniform flow, the convection takes the form of aidsymmetrlc with respect to the z-alds. But when uniform flow Is strong, velocity field and temperature field consist of a sin91e cell structure which spreads upstream side of the partial heating area. The flow pattern for strong uniform flows takes the form of positive temperatue near the ground and negative temperature perturbation soft over the partial heating area, and downward motion directly over the upwind portion of the partial heating area and upward motion on the downstream side. The downstream edge of the upstream cell Is shifted in the downstream direction with the Increase of uniform flow almost linearly.

• Journal of Mechanical Science and Technology
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• v.19 no.spc1
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• pp.305-311
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• 2005

This research presents a three-dimensional modeling technique for a flexible sheet. A relative coordinate formulation is used to represent the kinematics of the sheet. The three-dimensional flexible sheet is modeled by multi-rigid bodies interconnected by out-of-plane joints and plate force elements. A parent node is designated as a master body and is connected to the ground by a floating joint to cover the rigid motion of the flexible sheet in space. Since the in-plane deformation of a sheet such as a paper and a film is relatively small, compared to out-of-plane deformation, only the out-of-plane deformation is accounted for in this research. The recursive formulation has been adopted to solve the equations of motion efficiently. An example is presented to show the validity of the proposed method.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2010.10a
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• pp.397-400
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• 2010

The changing light condition of scene cause the luminance fluctuation of the captured image sequences. this artifact is called flicker, and would be easily recognized as visually unstable fluctuation. As the flicker degrades the performance of extracting useful information from image sequences, such as motion information or segmentation, it should be correction and linear flicker model. The algorithm model the flicker effects as a linear system with gain and offset parameter and estimates gain parameter with Gamma correction. The flicker reduction is performed by applying these parameters inversely th the ordinal sequences. To show the performance, we test out algorithm th the ground-truth sequences with the artificially added luminance fluctuation and real sequence with object motion.

• Journal of Ocean Engineering and Technology
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• v.17 no.2
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• pp.72-76
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• 2003

This paper presents the design concept and operation results of float-off for FSO (340,000 DWT Class, ELF AMENAM KPONO Project) built on the ground, without dry dock facilities. It was the first attempt to build FSO, completely, on the ground and launch it using DBU (Double Barge Unit, which was connected by rigid frame structure.) The major characteristics of FSO, which are similar to general VLCC type hull, including topside structure, weigh 51,000 metric ton. In order to have sufficient stability during the deck immersion of DBU, while passing through a minimum water plane area zone, proper trim control was completed with LMC (Load Master Computer). The major features of the monitoring system include calculation for transverse bending moment, shear force, local strength check of each connector, based on component stress, and deformation check during the load-out and float-off. Another major concern during the operation was to avoid damages at the bottom and sides of FSO, due to motion & movement after free-floating; therefore, adequate clearances between DBU and FSO were to be provided, and guide posts were installed to prevent side damage of the DBU casings. This paper also presents various measures that indecate the connector bending moment, damage stability analysis, and mooring of DBU during float off.

• Tunnel and Underground Space
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• v.6 no.2
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• pp.157-165
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• 1996

In order to analyze the effects of ground vibration caused by underground blasting having an effect on structure, the particle velocity and acceleration are calculated by using DYNPAK program. The DYNPAK program analyzes nonlinear transient dynamic problem and adopts the very popular and easily implemented, explicit, central difference scheme. In this program, the material behavior is assumed to be elasto-viscoplastic. Using the particle acceleration history, modal analysis method is applied to the forced vibration response of multiple-degree-of-freedom(MDOF) systems using unclupled equations of motion expressed in terms of the system's natural circular frequencies and modal damping factors. AS a means of evaluating the vibration behavior of building structure subjected to underground blasting, the time response of the displacements relative to the ground of five-story building is determined. It is concluded that the amount of explosives consumed per round, the location of structure, the properties of rock medium, the stiffness fo structure, etc. act on the important factors influencing on the safety of building and that the response of a structure subjected to a forced excitation can usually be obtained with reasonable accuracy by the modal analysis of only a few mode of the lower frequencies of the system.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.14 no.3
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• pp.453-462
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• 1994

Variation of seismic wave field in a multi-layered attenuating elastic half space is studied by the propagator matrix method and point source models of which fault-slip functions are defined as ramp functions. In this paper, the earth is modeled as being composed of horizontally stratified layers, with uniform material properties for each layer. The partial differential equations for the seismic motion in each layer are solved using a Fourier Hankel transform approach. Time histories and frequency contents of accelerations and displacements due to a vertical dip-slip and strike-slip point source located in the underlain half space are calculated at the layer interfaces using the developed programs and their characteristics are represented.