• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.5
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• pp.2579-2586
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• 2014

It is crucial to set up early the required performance of surface ship for preventing the risk factors such as an excess of performance, cost and period in development stage. In this study, MOP and MOE are proposed to establish the method for deriving alternatives, MOP represents the defensive effect for anti ship missiles and MOE is the ratio of cost and performance. The 16 engagement scenarios which selectively install RF decoy, RF jammer, CIWS and anti air missile are suggested. The simulation results by using NORAM tool operated by ROK Navy show that the ship survivability is 0.605~0.975 and MOP is 0.301~0.887. The analyzed results represent the operating scenario with RF decoy, RF jammer and short range anti air missile is the best cost and effectiveness measure.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.46 no.4
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• pp.218-228
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• 2023

Maintaining sea superiority through successful mission accomplishments of warships is being proved to be an important factor of winning a war, as in the Ukraine-Russia war. in order to ensure the ability of a warship to perform its duties, the survivability of the warship must be strengthened. In particular, among the survivability factors, vulnerability is closely related to a damage assessment, and these vulnerability data are used as basic data to measure the mission capability. The warship's mission capability is usually measured using a wargame model, but only the operational effects of a macroscopic view are measured with a theater level resolution. In order to analyze the effectiveness and efficiency of a weapon system in the context of advanced weapon systems and equipments, a warship's mission capability must be measured at the engagement level resolution. To this end, not the relationship between the displacement tonnage and the weight of warheads applied in the theater level model, but an engagement level resolution vulnerability assessment method that can specify physical and functional damage at the hit position should be applied. This study proposes a method of measuring a warship's mission capability by applying the warship vulnerability assessment method to the naval engagement level analysis model. The result can be used as basic data in developing engagement algorithms for effective and efficient operation tactics to be implemented from a single unit weapon system to multiple warships.

• Journal of the Society of Naval Architects of Korea
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• v.50 no.3
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• pp.182-189
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• 2013

In the development process of new naval ships, it is necessary to make the effort of the signature management and reduction of ship infrared(IR) signature to increase the ship survivability(susceptibility). So far the ship's contrast radiant intensity is used as a ship IR signature design criteria during the naval ship design stages. However, nowaday it is in a state of disorder at the basic design stage because of the lack of any related studies and methods. In this study, the IR signature management methods for improving the signature reduction and ship survivability are suggested by the comparison analysis of the advantages and disadvantages of signature management techniques. And also the criteria for the ship signature management are suggested when considering the infrared signature measuring assets and sea trial environments of the Korean peninsula.

• Journal of the Korea Institute of Military Science and Technology
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• v.21 no.3
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• pp.342-348
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• 2018

The important issue of equipment installed in maritime weapon system is shock survivability against underwater explosion(UNDEX). If the shock survivability of equipment should not be guaranteed, the successful mission also could not be achieved. For that reason, the shock-resistance of each equipment under UNDEX environment should be demonstrated before deployment at combat field. However, the actual UNDEX test on the ocean is too expensive to conduct. Also, it has diverse dangerous factors. The main characteristic of UNDEX is a dual-pulse shock. The vertical shock test machine able to simulate dual pulse shock signal on the ground will be introduced in this paper. The dual-pulse shock signal presented in certain shock standard was achieved with this shock-test machine on the ground. The analytical procedure to set a test condition was verified by comparing simulation result with experiment result.

• Journal of Communications and Networks
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• v.16 no.5
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• pp.534-547
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• 2014

Large-scale failures resulting from natural disasters or intentional attacks are now causing serious concerns for communication network infrastructure, as the impact of large-scale network connection disruptions may cause significant costs for service providers and subscribers. In this paper, we propose a new framework for the analysis and prevention of network service disruptions in large-scale failure scenarios. We build dynamic deterministic and probabilistic models to capture the impact of regional failures as they evolve with time. A probabilistic failure model is proposed based on wave energy behaviour. Then, we develop a novel approach for preventive protection of the network in such probabilistic large-scale failure scenarios. We show that our method significantly improves uninterrupted delivery of data in the network and reduces service disruption times in large-scale regional failure scenarios.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.20 no.4
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• pp.381-389
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• 2010

Modern military equipments are often required to be mounted on a truck for their survivability and operation performance. Special units installed on the truck at times experience serious shock vibration caused by obstacles of road and/or uncommon road shape. It is then essential to analyze the travel performance of truck-mounted special units for their survivability and performance. In this paper, shock responses of the equipments subjected to bump passing and wash board road are experimentally obtained and also analyzed via FEM. Modified bump configuration and road profile considering the interface with tire are suggested. Analytical results considering this modification show good agreement with test results.

• Journal of the Korean Society of Systems Engineering
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• v.20 no.1
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• pp.26-33
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• 2024

Since the positive viability field remains the way it was in the 2010s, the ship test evaluation in the viability field is being applied to withstand the attack on an extremely limited kind of weapon system even the latest ship. In response, this paper analyzed and considered maritime warfare during the Russia-Ukraine War, which is an example of the latest war paradigm shift, and diagnosed the status of test evaluation in the field of Naval ship survivability to derive realistic development measures such as reflecting threat development trends, strengthening attack and damage control evaluation, confirming ship viability limits, and realizing test evaluation plans.

• Journal of Advanced Research in Ocean Engineering
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• v.4 no.1
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• pp.7-15
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• 2018

The submarine is an underwater weapon system which covertly attacks the enemy. Pressure hull of a submarine is a main system which has to have a capacity which can improve the survivability (e.g., protection of crews) from the high pressure and air pollution by a leakage of water, a fire caused by outside shock, explosion, and/or operational errors. In addition, pressure hull should keep the functional performance under the harsh environment. In this study, optimal design of submarine pressure hull is dealt with 7 case studies done by analytic method and then each result's adequacy is verified by numerical method such as Finite Element Analysis (FEA). For the structural analysis by FEM, material non-linearity and geometric non-linearity are considered. After FEA, the results by analytic method and numerical method are compared. Weight optimized pressure hull initial scantling methods are suggested such as a ratio with shell thickness, flange width, web height and/or relations with radius, yield strength and design pressure (DP). The suggested initial scantling formulae can reduce the pressure hull weight from 6% and 19%.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.1
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• pp.255-261
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• 2013

In this paper, we developed and tested a program for prediction flash fire in a combat system. Purposes of the program are flash fire prediction of combat system for analysis vulnerability and survivability, and visualization for fire-related information. To do this, we defined critical components of the combat system which has probabilities of flash fire occurrence, and proposed Flash Fire Probability Tree which is based on Fault Tree Analysis(FTA). The program visualizes positions of critical components in combat system, positions of penetrated components, selected Flash Fire Probability Tree, temperature profile, and tables for properties of matters.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2003.10a
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• pp.122-122
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• 2003

This study examined the viability of canine oocytes following storage at 4 or $38{\circ}C$ for 5 hrs. The ovaries were collected from domestic dog following ovariohysterectomy at a local veterinary clinics and transported to laboratory In two different transport temperature at 4 or $38{\circ}C$ within 5 hrs. The cumulus oocyte complexes (COCs) were recovered after slicing with blade. In Exp. 1, the oocytes collected were matured in DMEM supplemented with l0% FBS, 0.6 mM/mlcysteine, 0.2 mM Pyruvic acid, 20 ng/ml $E_2$ and 1 $\mu g/ml$ rbST at humidified atmosphere containing 5% $CO_2 38{\circ}C$ for 24 or 48 hrs to analysis of survivability. In Exp 2, to assess nuclear development at 38{\circ}C$ group, the oocytes were matured in maturation medium for 24, 48 or 96 hrs. Survivability was judged by a morphological appearance and PI staining. Survivability rates were analyzed by General Linear Models procedure in SAS. The survival rates at 4{\circ}C$ ovary transport group showed significantly lower than at 38{\circ}C$ group (0 vs 72.9% in 48 hrs and 13.2 vs 77 8% in 24 hrs; P<0.05). The nuclear development of oocytes to MI to MII stages at 24, 48 and 96 hrs was 8.3% (6/72), 8.9% (9/101), and 9.5% (8/84). These results showed that the canine oocytes were remarkably sensitive to a low temperature and did not increase nuclear development rate depend on maturation time to 96 hrs.