• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.8
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• pp.1623-1631
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• 2016

There are many researches which analyze vulnerability for combat systems, have been progressing, and apply the analyzed result to reflect on design phase. Recently, there have been requirements for integrating the previous module based researches which conducted independently. In this paper, we propose an integrated vulnerability analysis method for the combat system considering characteristics of threats and protection performance of armors through an analysis of the advanced research. In addition, by applying the proposed method improves the existing hit probability analysis program and we are verified based on scenarios for improving survivability of PKM (Petrol Killer Medium) for vulnerability analysis confirmed the results. The proposed method improves reliability of vulnerability analysis by considering threats and defense ability. Also it able to satisfied with the integration requirements. Furthermore, we became buildup for the development of applied system and the method and integrated vulnerability analysis method for combat systems.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.41 no.10
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• pp.788-795
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• 2013

A magnesium bipolar plate whose surface was protected by thinly deposited silver layer was investigated as an alternative to existing graphite bipolar plate of PEM fuel cells. Thin silver layer of $3{\mu}m$ was deposited on a magnesium alloy substrate by physical vapor deposition (PVD) method in an environment of $180^{\circ}C$. A number of tests were conducted on the fabricated magnesium based bipolar plates to determine their suitability for use in PEM fuel cell stacks. The test on corrosion resistance in the same pH condition as in a PEM operation demonstrated the layer protected the magnesium alloy substrate, while unprotected substrate suffered from severe corrosion. The contact resistance of the fabricated bipolar plate was less than $20m{\Omega}-cm^2$ which was superior to the conventional bipolar plates. A single cell was constructed using the fabricated bipolar plates and power output was measured. Due to the enhanced conductivity caused by low contact resistance, slight increase was observed in current density and output voltage. With low density of the magnesium substrate and ease on machining, the weight reduction of the stack of 30~40 % is possible to produce the same power output.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.9
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• pp.49-56
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• 2020

High temperature heat generated during rifle firing not only degrades the performance of the weapon, but also limits the user's operation. In this study, temperature change of handguard according to firing was measured with reference to Human Engineering criteria and the operability according to material was examined. Accordingly, for the firing test, three types of Korean rifle and one overseas model were selected for each material of handguard, and firing test was conducted using a contact type temperature meter. The test result shows that using a plastic handguard with low thermal conductivity and aluminum handguard with high thermal conductivity enabled the rifles to be operated with bare hands even when firing at more than 100 rounds at low atmospheric temperature. However, when firing more than 60 rounds at over 20℃ atmospheric temperature, aluminum handguard use is limited. When firing quickly over 100 rounds, handguard use is restricted regardless of its fabrication material. To eliminate operational limitations by overheating, it is necessary to eliminate direct contact with skin using gloves, vertical grips, etc. This study examined the operability of rifles in terms of thermal risk, and the resulting study results are expected to be used as basic data for Human Engineering of other rifles and munitions.

• Korean Journal of Optics and Photonics
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• v.24 no.4
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• pp.176-183
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• 2013

In this paper, we report the design, fabrication and characterization of the 3-Dimensional optical receiver for a Laser Detection And Ranging (LADAR) system. The optical receiver is composed of three parts; $16{\pm}16$ Geiger Mode InGaAs Avalanche Photodiode (APD) array device operated at 1560 nm wavelength, Read Out Integrated Circuit (ROIC) measuring the Time-Of-Flight (TOF) of the return signal reflected from target objects, a package and cooler maintaining the proper operational condition of the detector and control electronics. We can confirm that the LADAR system can detect the signal from a target up to 1.2 km away, and it showed low Dark Count Rate (DCR) of less than 140 kHz, and higher than 28%-Photon Detection Efficiency (PDE). This is considered to be the best performance of the $16{\pm}16$ FPA APD optical receiver for a LADAR system.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.6
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• pp.74-79
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• 2019

The military vehicle produces electric power through an engine-integrated serial hybrid generator that is connected to the engine and does not have a separate generator installation space. However, depending on the mechanical characteristics of the connection between the generator and the engine, iron oxide for internal rusting and lubrication grew scattered. The iron oxide is adhered to the starter to deteriorate the starting performance, and there is a problem that the noise of the leg due to wear of the gear is increased. To solve this problem, the connection spline material and the surface treatment of the engine were improved and the shape was changed to a grease sealing type to prevent the generation of iron oxide inside. As the shape of the generator connector composing the shafting system was changed, the integrity of the structure was confirmed through the torsional endurance test. In addition, through the actual vehicle load test, it was verified that no corrosion occurred during the target life span without internal corrosion. It was confirmed that the anti-scattering structure of the grease effectively suppresses the generation of iron oxide, thereby reducing the noise generated from the generator. In this paper, we propose a fundamental solution to the degradation of the starter and the noise generation by preventing the back corrosion caused by the serial hybrid generator installed between the engine and the transmission.

• Journal of the Korea Society for Simulation
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• v.29 no.4
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• pp.33-46
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• 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 Broadcast Engineering
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• v.27 no.6
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• pp.936-939
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• 2022

As air combat system technologies developed in recent years, the development of air defense systems is required. In the operating concept of the anti-aircraft defense system, selecting an appropriate armament for the target is one of the system's capabilities in efficiently responding to threats using limited anti-aircraft power. Much of the flying threat identification relies on the operator's visual identification. However, there are many limitations in visually discriminating a flying object maneuvering high speed from a distance. In addition, as the demand for unmanned and intelligent weapon systems on the modern battlefield increases, it is essential to develop a technology that automatically identifies and classifies the aircraft instead of the operator's visual identification. Although some examples of weapon system identification with deep learning-based models by collecting video data for tanks and warships have been presented, aerial vehicle identification is still lacking. Therefore, in this paper, we present a model for classifying fighters, helicopters, and drones using a convolutional neural network model and analyze the performance of the presented model.

• Information Systems Review
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• v.19 no.3
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• pp.23-45
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• 2017

The ROK military is making a great effort and investment in establishing network-centric warfare, a future battlefield concept, as a major step in the establishment of a basic plan for military innovation. In the military organization level, an advanced process is introduced to shorten the command control time of the military and the business process is improved to shorten the decision time. In the information system dimension, an efficient resource management is achieved by establishing an automated command control system and a resource management information system by using the battle management information system. However, despite these efforts, we must evaluate the present level of informatization in an objective manner and assess the current progress toward the future goal of the military by using objective indicators. In promoting informatization, we must systematically identify the correct areas of improvement and identify policy directions to supplement in the future. Therefore, by analyzing preliminary research, workshops, and expert discussions on the major informatization level evaluation models at home and abroad, this study develops an evaluation model and several indicators that systematically reflect the characteristics of military organizations. The developed informatization level evaluation model is verified by conducting a feasibility test for the troops of the operation class or higher. We expect that this model will be able to objectively diagnose the level of informatization of the ROK military by putting budget and resources into the right place at the right time and to rapidly improve the vulnerability of the information sector.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.4
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• pp.99-107
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• 2021

To establish an effective performance appraisal system, ratee accountability is essential because it increases the likelihood of meaningful utilization of performance appraisal feedback. In the context of a multi-rater performance appraisal system, this study examines the effect of the ratee general accountability and accountability to the supervisor and peers on the ratee's intention to change behavior based on the performance appraisal feedback. This study further explored the moderating effect of perceived feedback specificity on the relationship between the ratee accountability and behavioral change intention. Hierarchical multiple regression analysis was conducted using the survey data from 153 employees in eight firms with multi-rater performance appraisal systems. The results showed that ratee general accountability was positively associated with the intention to change behavior. Furthermore, perceived feedback specificity attenuated the positive relationship between the ratee general accountability and behavioral change intention, which was the opposite of the hypothesized direction. The findings indicate the importance of managing and facilitating ratee accountability for implementing a multi-rater performance appraisal system. The result also emphasizes the critical role that performance appraisal feedback plays in motivating performance improvement by providing flexible, constructive advice and behavioral change strategies instead of inducing self-defense or justification.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.5
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• pp.343-354
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• 2017

This study was designed to identify the knowledge, perception, self-efficacy, and performance on radiation protection among perioperative workers in terms of radiation protection. The factors affecting the performance of radiation protection were identified, and provide basic data for the development of an effective radiation protection education program. The sample was comprised of 166 perioperative workers who agreed to participate in this descriptive study. Data analysis was performed using the t-test, analysis of variance, Pearson's correlation, and multiple regression analyses on the SPSS 23.0 Program. The average time of radiation exposure was 3-4hoursThe radiation protection education experience was 11.4%. The average score of radiation protection knowledge was $8.61{\pm}2.51$; the perception was $4.59{\pm}0.64$; and the performance was $2.99{\pm}0.90$ There was a significant difference in the degree of radiation defense knowledge and performance among the general characteristics (p <001). Knowledge of radiation protection was correlated with the perception. The performance of radiation protection was correlated with the knowledge. The knowledge and perception of radiation protection behaviors should be increased to improve radiation protection performance. Therefore, it is important to promote the performance of radiation protection behaviors by improving the perioperative workers' knowledge of radiation protection through reinforcing radiation-related education.