• Journal of the Korea Institute of Military Science and Technology
• /
• v.13 no.5
• /
• pp.759-768
• /
• 2010

In next war, it will be expected that some requirement such as information acquisition, battlefield surveillance and control, increased power projection, precision attack by guided missile and electronic warfare may have special importance. The use of robot weapon system by Airforce will make up for some weak points of man based weapon system that Airforce currently has. And Airforce man/robot combined air vehicle weapon system can extend military operational theater and give its flexibility in next war where power, mobility and information should be all-in-one for military purpose.

• Journal of the Korean Society for Industrial and Applied Mathematics
• /
• v.19 no.3
• /
• pp.271-287
• /
• 2015

In this article, a more generalized form of the impact time and angle control guidance law is proposed based on the linear quadratic optimal control methodology. For the purpose on controlling an additional constraint such as the impact time, we introduce an additional state variable that is defined to be the jerk (acceleration rate). Additionally, in order to provide an additional degree of freedom in choosing the guidance gains, the performance index that minimizes the control energy weighted by an arbitrary order of time-to-go is considered in this work. First, the generalized form of the impact angle control guidance law with an additional term which is used for the impact time control is derived. And then, we also determine the additional term in order to achieve the desired impact time. Through numbers of numerical simulations, we investigate the superiority of the proposed guidance law compared to previous guidance laws. In addition, a salvo attack scenario with multiple missile systems is also demonstrated.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.18 no.3
• /
• pp.8-16
• /
• 2014

This paper analyzes the effects of sideslip angle(SA) on the buzz margin of supersonic intake. The buzz margin is assumed to be stabilized by a controller which generates command depending only on the longitudinal sensor measurements. The analysis is performed based on three dimensional CFD results with which the sensor measurements can be simulated. In such a control system based on the longitudinal measurements, unexpected lateral flow perturbation results in the increase in the total angle of attack(TAoA), that causes the degradation of the engine intake performance. As a consequence, it is shown that the control stability is reduced such that additional control margin needs to be secured.

• Journal of the Korea Society for Simulation
• /
• v.24 no.3
• /
• pp.89-96
• /
• 2015

In order to use missiles more effectively, assessing methodologies was advanced about weapon effects for various target types. We tried to find out the most effective analysis methodologies for missiles to attack 3 dimensional building target's and analyzed adaptedness as an assessing methodology. There are EFD (Expected Fractional Damage) and SSPD (Single Sortie Probability of Damage) methodologies to assess building target damage. In order to calculate effectiveness we used input parameter such as size of the target and CEP (Circular Error Probable), MAE_bldg (Mean Area of Effects for Building) of weapons and impact angle as encountering condition between the target and the missile. We compared EFD and SSPD, in order to analyze adaptedness as a effective methodology by CEP and MAE. The result was that EFD methodology was more adaptive to assess 3 dimensional building targets by missile systems than SSPD.

• Strategy21
• /
• s.41
• /
• pp.52-84
• /
• 2017

After finishing Cold War, the U.S. Navy's ability to Sea control has been gradually eroded last 15-20 years. The global security environment demands that the surface Navy rededicate itself to sea control, as a new group of potential adversaries is working to deny U.S. navy command of the sea. China has been increasing their sea denial capability, such as extended anti-surface cruise missile and anti-surface ballistic missile. To cope with this situation, the U.S. Naval Surface Forces Command has announced Surface Forces Strategy: Return to Sea Control. It is a new operating and organizing concept for the U.S. surface fleet called 'distributed lethality'. Under distributed lethality, offensive weapons such as new ASCMs are to be distributed more widely across all types of Navy surface ships, and new operational concept for Navy surface fleet's capability for attacking enemy ships and make it less possible for an enemy to cripple the U.S. fleet by concentrating its attack on a few very high-value Navy surface ships. By increasing the lethality of the surface ships and distributing them across wide areas, the Navy forces potential adversaries to not only consider the threat from our carrier-based aircraft and submarines, but they now consider the threat form all of those surface ships. This idea of using the distributed lethality template to generate surface action groups and adaptive force package and to start thinking about to increase the lethal efficacy of these ships. The U.S. Navy believes distributed lethality increases the Navy's sea control capability and expands U.S. conventional deterrence. Funding new weapons and renovated operating concept to field a more lethal and distributed force will enable us to establish sea control, even in contested area. The U.S. Navy's Surface Forces Strategy provides some useful implications for The ROK Navy. First the ROK Navy need to reconsider sea control mission. securing sea control and exploiting sea control are in a close connection. However, recently the ROK Navy only focuses on exploiting sea control, for instance land attack mission. the ROK Navy is required to reinvigorate sea control mission, such as anti-surface warfare and anti-air warfare. Second, the ROK Navy must seek the way to improve its warfighting capability. It can be achieved by developing high-edge weapons and designing renewed operating concept and embraced new weapon's extended capabilities.

• Journal of the Korea Society for Simulation
• /
• v.29 no.4
• /
• pp.33-46
• /
• 2020

The purpose of Electronic warfare is to disturbe, neutralize, attack, and destroy the opponent's electronic warfare weapon system or equipment. Suppression of Enemy Air Defense (SEAD) mission is aimed at incapacitating, destroying, or temporarily deteriorating air defense networks such as enemy surface-to-air missiles (SAMs), which is a representative mission supported by electronic warfare. This paper develops a simulator for analyzing the effectiveness of SEAD missions under electronic warfare support using C++ language based on the DEVS (Discrete Event Systems Specification) model, the usefulness of which has been proved through case analysis with examples. The SEAD mission of the friendly forces is carried out in parallel with SSJ (Self Screening Jamming) electronic warfare under the support of SOJ (Stand Off Jamming) electronic warfare. The mission is assumed to be done after penetrating into the enemy area and firing HARM (High Speed Anti Radiation Missile). SAM response is assumed to comply mission under the degraded performance due to the electronic interference of the friendly SSJ and SOJ. The developed simulator allows various combinations of electronic warfare equipment specifications (parameters) and operational tactics (parameters or algorithms) to be input for the purpose of analysis of the effect of these combinations on the mission effectiveness.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.49 no.2
• /
• pp.95-106
• /
• 2021

Side-jets enable the immediate maneuver of a missile compared to control surfaces; however, they may cause adverse effects on aerodynamic coefficients, for they interfere with freestream. To find out the impact of side-jets on aerodynamic coefficients, we simulate side-jets as air gas and utilize multi-fidelity models to evaluate differences between aerodynamic coefficients obtained with and without side-jets. We computed differences in aerodynamic coefficients to investigate side-jet effects for the changes of a Mach number, a bank angle, and an angle of attack. As a result, asymmetrically developed side-jets affect the longitudinal force and moment coefficients, and the lateral force and moment coefficients drastically change in-between -30 and 30 degrees of bank angles. In contrast, side-jets hardly influence the axial force coefficients. As for the axial moment coefficient, we could not determine the side-jet effect due to a lack of aerodynamic coefficient samples in the Mach number. All in all, we confirm that side-jets lead to the change of a missile attitude as they considerably vary the longitudinal and lateral aerodynamic coefficients.

• Journal of Satellite, Information and Communications
• /
• v.12 no.3
• /
• pp.54-62
• /
• 2017

China has invested for military satellite technology development to construct the space-based surveillance system from existing land-based and aerostat surveillance system since 1960s to react rapidly for deployment of marine force of United States and surrounding nations in west Pacific, south China sea and Indian ocean. China has also launched about 40 the Yaogan military intelligence satellites series for EO, SAR and ELINT fields since 2006 after the required technique with several technical experiment satellites launch and operational test. ELINT satellites transmit data from satellite to earth station in real time with construction space-based network around it. Those data are simultaneously delivered to Anti-Ship Ballistic Missile(ASBM) connected land-based C4ISR network for marine target attack. Therefore China has enhanced surveillance and attack capability to the surrounding marine nations with space-based network around it. In the future, It is considered that China will increase accurate location search, signal processing and analysis ability through a further study on its technology.

• Advances in aircraft and spacecraft science
• /
• v.4 no.1
• /
• pp.37-52
• /
• 2017

Gas turbines operating in dusty or sandy environment polluted with micron-sized solid particles are highly prone to blade surface erosion damage in compressor stages and molten sand attack in the hot-sections of turbine stages. Commercial/Military fixed-wing aircraft engines and helicopter engines often have to operate over sandy terrains in the middle eastern countries or in volcanic zones; on the other hand gas turbines in marine applications are subjected to salt spray, while the coal-burning industrial power generation turbines are subjected to fly-ash. The presence of solid particles in the working fluid medium has an adverse effect on the durability of these engines as well as performance. Typical turbine blade damages include blade coating wear, sand glazing, Calcia-Magnesia-Alumina-Silicate (CMAS) attack, oxidation, plugged cooling holes, all of which can cause rapid performance deterioration including loss of aircraft. The focus of this research work is to simulate particle-surface kinetic interaction on typical turbomachinery material targets using non-linear dynamic impact analysis. The objective of this research is to understand the interfacial kinetic behaviors that can provide insights into the physics of particle interactions and to enable leap ahead technologies in material choices and to develop sand-phobic thermal barrier coatings for turbine blades. This paper outlines the research efforts at the U.S Army Research Laboratory to come up with novel turbine blade multifunctional protective coatings that are sand-phobic, sand impact wear resistant, as well as have very low thermal conductivity for improved performance of future gas turbine engines. The research scope includes development of protective coatings for both nickel-based super alloys and ceramic matrix composites.

• Journal of the Korea Society for Simulation
• /
• v.29 no.4
• /
• pp.47-54
• /
• 2020

North Korea has recently developed and deployed missiles with various ranges as asymmetrical forces. Among them, short-range ballistic missiles with improved accuracy are expected to aim at achieving tactical goals by hitting important military facilities in Korea with a small number of missiles. Damage to the air force airfields, one of North Korea's main targets of missiles attack, could limit the operation of air force fighters essential to gaining air superiority. Based on the attack by the short range ballistic missiles, the damage probability of military airfields was simulated. And as the one of the concepts of passive defense, the way to reduce the loss of combat power was studied through the changes of the air force squadrons deployment. As a result, the effective deployment plan could be obtained to reduce the amount of power loss compared to the current deployment.