• Proceedings of the KSRS Conference
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• 2007.10a
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• pp.489-492
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• 2007

At COMS SOC, 13m antenna system will serve to transmit command and receive telemetry in S-Band for COMS operation. In addition, Sensor Data and LRIT/HRIT in L-Band will be received and LRIT/HRIT in S-Band will be transmitted through this antenna system. In many cases, G/T is used as barometer to estimate the receiving capability of antenna system. To estimate G/T, this paper presents two approaches, one is analysis based on the specification of antenna and RF equipment while the other is measurement by using Sun. From the results, G/T was proven as more than 20dB/K and it means that the required G/T, 19dB/K is verified successfully.

• Proceedings of the KSRS Conference
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• 2007.10a
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• pp.482-485
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• 2007

The S-Band SSPA is front-end equipment to transmit both LRIT and HRIT to COMS. To provide the required EIRP, S-Band SSPA is designed to generate maximum 1kW power at its 1dB gain compression point (P1dB). Due to the operation for 24 hours per seven days, the verification on the performance of S-Band SSPA was performed thoroughly. This paper presents that major requirements such as maximum 1kW power, maximum -26dBc of IMD characteristic at 500W output and around -57dBc of coupling factor were verified through proposed test configuration.

• Journal of Advanced Navigation Technology
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• v.24 no.6
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• pp.471-478
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• 2020

In this paper, we develop the ground risk model of unmanned aerial vehicle (UAV) operation to quantify the ground risk when the UAV falls to the ground during the intended operation in case of UAV failure. The ground risk is computed by using the UAV failure probability, the probability of impact a person when UAV falls to the ground, the probability of fatality when UAV strikes the person. We mathematically derive each probability to evaluate the ground risk of UAV operation. Also, the population density map, building to land ratio map, car traffic database is used to estimate the number of people exposed to collision with UAV. Finally, we assumed the operations of a UAV with two paths in Daejeon city and evaluate the ground risk of each UAV operations.

• Land and Housing Review
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• v.9 no.4
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• pp.25-32
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• 2018

Application of geothermal energy in buildings has been gaining popularity as it provides the benefits of both heating and cooling a building. Among the various types of geothermal energy systems, ground-coupled heat pump system is the most commonly applied one in South Korea. A ground heat exchanger plays an important role as a heat source in winter and a heat sink in summer. For the stable operation of a ground-coupled heat pump system, a ground heat exchanger should be sized so that it provides sufficient heating and cooling energy. Heating and cooling energies generated in ground heat exchangers mainly depend on the temperature difference between the heating medium in ground heat exchangers and the surrounding ground. In addition, the performance of ground heat exchangers influences the change in ground temperature. Therefore, it is necessary to consider this interrelation between the change in the ground temperature and the performance of ground heat exchanger for an accurate estimation of its performance. However, previous thermal analysis models for ground heat exchangers are not competent enough to allow a complete understanding of this interrelation. Therefore, this study proposes a three-dimensional equivalent, transient ground heat exchanger analysis model. First, a previous thermal analysis model for ground heat exchangers, including an analytical model, a g-function, and a numerical model are analyzed. Next, to overcome the limitations of the previous models, a three-dimensional equivalent, transient ground heat exchanger model is proposed. Finally, this study validated the proposed model with the measurement data of the thermal response test, sandbox test, and TRNSYS DST model. All validation results showed a good agreement. These findings helped us to investigate the thermal performance of ground heat exchangers more accurately than the analytical models, and faster than the numerical models. Furthermore, the proposed model contributes to the design of ground heat exchangers by considering the different operation conditions of buildings.

• Journal of the Korea Institute of Military Science and Technology
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• v.26 no.5
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• pp.431-438
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• 2023

The information about battlefield environment changes and operational impacts on Korean Peninsula due to climate change is essential for national defense. In this study, the future impact of four ground operations was analyzed by using the national climate change standard scenario based on the IPCC 6^th report. As a result, it was analyzed that the number of operational-limited days for ambush and airlift operations would decrease, making the operational environment favorable. However, the operational environment unfavorable as the number of operational-limited days for crossing and reconnaissance operations increase, but the number is not large so much.

• Journal of Astronomy and Space Sciences
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• v.20 no.3
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• pp.227-238
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• 2003

Spacecraft mission planning functions including event prediction, mission scheduling, command planning, and ground track display have been developed for the KOMPSAT-2 mission operations. Integrated event prediction functions including satellite orbital events, user requested imaging events, and satellite operational events have been implemented. Mission scheduling functions have been realized to detect the mission conflicts considering the user specified constraints and resources, A conflict free mission scheduling result is mapped into the spacecraft command sequences in the command planning functions. The command sequences are directly linked to the spacecraft operations using eXtensible Markup Language(XML) for command transmission. Ground track display shows the satellite ground trace and mission activities on a digitized world map with zoom capability.

• Journal of the military operations research society of Korea
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• v.17 no.2
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• pp.31-43
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• 1991

The fire effectiveness and the operationability of the ground weapon system (such as tank, armored vehicle, howitzer, MLRS, ${\cdots}$), whose operations are usually happened on the ground, are dependent not only on their performances but also on the terrain environments. Especially, the artillery weapons systems' effectiveness is largely varied, because their maneuverability (such as translation, occupation of their sites) and the fire effectiveness are very dependent on the terrain. In this paper, presented are the methods how to analyze the terrain using the digital terrain data. And a software (which are implemented on the IBM PC compatible personal computer) is developed for the analysis of the terrain using the various method of computer Aided Geometric Design and Modeling. The S/W is expected to be very useful for the evaluation of the artillery weapon systems and for the commanders' decision making.

• Journal of Korean Institute of Industrial Engineers
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• v.42 no.6
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• pp.386-394
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• 2016

In this research, in order to optimize the multi-objective function effectively, we suggested the optimization model to maximize the total destruction of ground targets and minimize the total damage of aircrafts and cost of air munitions by using goal programming. To satisfy the various variables and constraints of this mathematical model, the concept of air strike package is applied. As a consequence, effective attack can be possible by identifying the prior ground targets more quickly. This study can contribute to maximize the ROK air force's combat power and preservation of high value air asset in the war.

• International Journal of Advanced Culture Technology
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• v.12 no.1
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• pp.16-19
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• 2024

One of the current focal points in the defense sector is how to strategically leverage the technologies of the Fourth Industrial Revolution in military operations. The Fourth Industrial Revolution denotes a transformational shift in the environment where automation and connectivity are maximized, primarily driven by advancements in machine learning and artificial intelligence. Coined by Klaus Schwab at the 2015 Davos Forum, this term signifies a profound change in human activities, akin to how a single machine replaced hundreds of laborers in the past. The military application of Fourth Industrial Revolution technologies is increasingly researched and anticipated to be actively implemented. Combat, as a subset of warfare, entails military actions between units conducting war. Typically performed by units to achieve one or more objectives, the concept of combat involves the fundamental ideas guiding the conduct of military operations against adversaries, both presently and in the future. Hence, it is imperative for our military to develop future combat concepts by harnessing the key technologies of the Fourth Industrial Revolution.

• Tunnel and Underground Space
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• v.7 no.4
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• pp.267-273
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• 1997

Rock fragmentation with plasma blasting technique has advantageous properties in contrast to the conventional blasting method in controlling of flying rocks and ground vibrations, when residents are complaining or surrounding structures stay in protection from blasting operations. The experiences show in urban construction works that the plasma blasting is the most possible method to prevent damages and minimize adverse environmnetal impacts. The fragmentation energy level is evaluated by numerical simulation using PFC-2D for various drill hole pattern and tested accordingly to get the feasibility. The energy output of plasma blasting system has been improved to a level of 1 MJ, which can break a 2~3 ㎥ granite boulder or 1.5 m height bench face. Measurements are carried out to get the ground vibration level and propagation equation, so that the control of the blasting operations can be performed more precisely and safely.