• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.35 no.9
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• pp.826-835
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• 2007

Solar heat flux data is needed for thermal load prediction of launch vehicle. In order to predict the solar flux, several solar flux models have been compared and a new model is developed. Most of the models can predict well the direct solar flux, but show some errors in the scattered solar flux. The newly developed model considered isotropic and anisotropic scattered solar fluxes, and the predicted solar flux agreed well with the measured. Because the present model can be used at any longitude, latitude, day and altitude, the model would be an useful tool to predict the thermal load of the launch vehicle and the vehicles which have to consider the solar heat.

• Journal of Institute of Control, Robotics and Systems
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• v.21 no.3
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• pp.217-223
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• 2015

Autonomous driving is no longer atechnology of the future since the development of autonomous vehicles has now been realized, and many technologies have already been developed for the convenience of drivers. For example, autonomous vehicles are one of the most important drive assistant systems. Among these many drive assistant systems, Cruise Control Systems are now a typical technology. This system constantly maintains a vehicle's speed and distance from a vehicle in front by using Radar or LiDAR sensors in real time. Cruise Control Systems do not only serve their original role, but also fulfill another role as a 'Driving Safety' measure as they can detect a situation that a driver did not predict and can intervene by assuming a vehicle's longitude control. However, these systems have the limitation of only focusing on driver safety. Therefore, in this paper, an Intelligent Cruise Control System that utilizes the path planning method and GIS is proposed to overcome some existing limitations.

• Journal of Environmental Science International
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• v.12 no.2
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• pp.163-170
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• 2003

Seosan A, B area is located on 36°42' of north parallel and 126°27' of east longitude. It consisted of broad artificial lakes and reclaimed agricultural lands; there is Ganwalho lake in A area and Bunamho lake in B area. Total birds surveyed four times in 2001 at the A area are 105,580 of 11 orders, 28 families, 89 species. Among them, resident species were 21 species including Pica pica. Twenty species including Cuculus canorus were summer migrants, and 30 species including Platalea leucorodia were winter migrants. Seventeen species including Limosa limosa were occasionally species. And Rostratula benghalensis was an unconfirmed species. Species diversity index (H') was 0.72; species equally common index (e/sup H'/) was 2.06. In January, maximum observed 102,121 individuals. However in July 52 species were observed most variously. There were total 81,152 birds observed with 11 orders, 22 families, and 71 species at the B area. Fifteen species including Falco tinnumculus were resident species. Summer migrants were 18 species including Ixobychus sinensis. Winter migrants were 25 species including Ciconia boyciana. Thirteen species including Tringa glareola were occasionally species. Species diversity index (H') was 0.281; species equally common index (e/sup H'/) was 1.325. In January, maximum observed 78,433 individuals. However in Silly 42 species were observed most variously.

• Aerospace Engineering and Technology
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• v.12 no.2
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• pp.163-172
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• 2013

Communication Ocean Meteorological Satellite (COMS) has the hybrid mission of meteorological observation, ocean monitoring, and telecommunication service. The COMS is located at $128.2^{\circ}$ East longitude on the geostationary orbit and currently under normal operation service since April 2011. For the sake of the executions of the meteorological and the ocean mission as well as the satellite control and management, the satellite mission planning is daily performed. The satellite mission plans are sent to the satellite by the real-time operation and the satellite executes the missions as per the mission plans. In this paper the mission planning for COMS normal operation is discussed in terms of the ground station configuration and the characteristics of daily, weekly, monthly, and seasonal mission planning activities. The successful mission planning is also confirmed with the first one-year normal operation results.

• Journal of computational fluids engineering
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• v.10 no.2
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• pp.7-14
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• 2005

In this study, the shallow water equations on the sphere is simulated by the proposed method which has high spatial resolution and is based on the CIP(Cubic Interpolated Pseudoparticle) method. The governing equations are approximated on the longitude-latitudinal coordinate system. To avoid the problems resulting from the convergence of the meridians toward high-latitude and singularities on the poles, the semi-Lagrangian and finite volume method are employed. in addition, the CIP method is employed to solve the advection equations and is extended to apply on the equations in the polar coordinate system. The mathematical formulation and numerical results are also described. To verify of the efficiency, accuracy and capability of proposed algorithm, the standard test cases proposed bv Williamson et. al are simulated and the results are compared with other results. As a result, it is found that the present scheme gives a good properties in preserving shapes of solution and settles the pole problems in solving the shallow water equations on the sphere.

• KIPS Transactions on Computer and Communication Systems
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• v.4 no.4
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• pp.125-134
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• 2015

In this paper, we present an algorithm based on particle filter to determine the state of human movement. We calculate speed from consecutive positioning data with time, latitude and longitude. The speed values are averaged with previous speed values and thus act as basis for particle filter. We use the fact that human speed distribution follows exponential distribution approximately. An algorithm based on particle filter has been developed and utilized. Human movement state are probabilistically described in this research, and the probability is to determine whether a person is in moving state or in stable state. The experimental results are provided in various ways.

• Atmosphere
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• v.16 no.3
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• pp.225-234
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• 2006

Convective systems propagate eastward with a persistent pattern in the longitude-time space. The characteristic structure and fluctuation of convective system is helpful in determining its predictability. In this study, convective index (CI) was defined as a difference between GOES-9 window and water vapor channel brightness temperatures following Mosher (2001). Then the temporal-spatial scales and variational characteristics of the summer convective systems in the East Asia were analyzed. It is found that the average moving speed of the convective system is about 14 m/s which is much faster than the low pressure system in the summer. Their average duration is about 12 hours and the average length of the cloud streak is about 750km. These characteristics are consistent with results from other studies. Although the convective systems are forced by the synoptic system and are mostly developed in the eastern edge of the Tibetan Plateau, they have a persistent pattern, i.e., appearance of the maximum intensity of convective systems, as they approach the Korean Peninsula. The consistency of the convective systems, i.e., the eastward propagation, suggests that there exists an intrinsic predictability.

• Journal of Satellite, Information and Communications
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• v.3 no.2
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• pp.43-47
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• 2008

COMS is the one of Korean hybrid geostationary satellite and is scheduled to be launched in 2009 by Arian V into $128^{\circ}$ E longitude. COMS is designed and manufactured for three main objectives which are Communications, Oceanographic, and Meteorological missions. It provides the weather monitoring, ocean monitoring, and Ka band satellite communication services by means of three different payloads. The Ka band communications payload was developed by Electronics and Telecommunications Research Institute (ETRI), and provides not only the digital transmission for the communication services against natural disaster but also digital transmission for the high speed multimedia services. This paper describes the overview of the electrical and mechanical design and measured performances of the Ka band communications transponder flight model (FM) for COMS.

• Journal of Astronomy and Space Sciences
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• v.14 no.2
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• pp.381-385
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• 1997

A long-term prediction algorithm of geostationary orbit was developed using the analytical method. The perturbation force models include geopotential upto fifth order and degree and luni-solar gravitation, and solar radiation pressure. All of the perturbation effects were analyzed by secular variations, short-period variations, and long-period variations for equinoctial elements such as the semi-major axis, eccentricity vector, inclination vector, and mean longitude of the satellite. Result of the analytical orbit propagator was compared with that of the cowell orbit propagator for the KOREASAT. The comparison indicated that the analytical solution could predict the semi-major axis with an accuracy of better than $pm35$ meters over a period of 3 month.

• Journal of Astronomy and Space Sciences
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• v.35 no.3
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• pp.175-183
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• 2018

Many recent satellites have mission periods longer than 10 years; thus, satellite-based local space weather monitoring is becoming more important than ever. This article describes the instruments and data applications of the Korea Space wEather Monitor (KSEM), which is a space weather payload of the GeoKompsat-2A (GK-2A) geostationary satellite. The KSEM payload consists of energetic particle detectors, magnetometers, and a satellite charging monitor. KSEM will provide accurate measurements of the energetic particle flux and three-axis magnetic field, which are the most essential elements of space weather events, and use sensors and external data such as GOES and DSCOVR to provide five essential space weather products. The longitude of GK-2A is $128.2^{\circ}E$, while those of the GOES satellite series are $75^{\circ}W$ and $135^{\circ}W$. Multi-satellite measurements of a wide distribution of geostationary equatorial orbits by KSEM/GK-2A and other satellites will enable the development, improvement, and verification of new space weather forecasting models. KSEM employs a service-oriented magnetometer designed by ESA to reduce magnetic noise from the satellite in real time with a very short boom (1 m), which demonstrates that a satellite-based magnetometer can be made simpler and more convenient without losing any performance.