• Journal of the Korea Institute of Military Science and Technology
• /
• v.19 no.5
• /
• pp.662-668
• /
• 2016

Defense specification suitability review task means to examine whether to need enactment, amendment or abolition of defense specification, and realistic and efficient review environment are urgently needed by improving system. For the promotion of efficient tasks, the cycle of defense specification suitability review needs to be changed to 5 years for active specifications and 10 years for inactive specifications. To simplify the standards of defense specification suitability review, the distinction between prior management items and general management items should be abolished and the number of review items need to be reduced from ten to three. Also, in order to promote substantial defense specification suitability review, a system improvement is needed to utilize retired professionals from defense acquisition related agencies.

• Journal of Korean Society for Quality Management
• /
• v.49 no.3
• /
• pp.269-279
• /
• 2021

Purpose: The purpose of this study was to suggest weapon system specifications for requirements of Condition-Based Maintenance(CBM/CBM⁺). Methods: The military documents and case studies with regard to condition-based maintenance were reviewed. Representative Korea defense specifications of weapon system such as an aircraft, a C4ISR etc. were analyzed and investigated the level of requirement for maintainability was. Results: Condition-based maintenance was defined in both U.S. instruction and Korean directive. While deparment of defense(U.S.) provide a guidebook for CBM⁺, detailed instruction was not sufficient for Korean. Ministry of national defense(ROK) define the CBM⁺ by means of IPS element which should be developed along with the system development. The maintainability was barely included in Korean defense specifications, except for BIT(Built-in test) function. As a first step for defining the condition-based maintenance requirement in defense specification, this study suggests a standard form for data needed to acquire according to types of system, fault, failure, and so on. Conclusion: The empirical researches on CMB/CBM⁺ with domestic weapon systems are not enough, and a logic which leads the maintenance strategy to CMB/CBM⁺ is not solved. Through technical researches and institutional improvements including this study, we hope that condition-based maintenance would be fully established in the Korean defense field.

• Journal of the Korean Society of Systems Engineering
• /
• v.10 no.1
• /
• pp.81-86
• /
• 2014

Systems Engineering application focused on requirement definition and management for SURION System Development Project is described in this paper. To perform the development process effectively based on systems engineering processes; Requirements Definition, Design Review, Configuration Management, Quality Assurance, Data Management, are applied in this project. In this processes, the Stakeholder's Requirements are transferred to Specifications verified with design reviews, prototyping inspections, and integration tests. All engineering data, especially verification plan & results are recorded, and traced to each requirements of system specification in Surion database. Therefore, it could be assured that all requirements of specification are evaluated and verified successfully in Surion Project.

• Journal of the military operations research society of Korea
• /
• v.33 no.1
• /
• pp.135-155
• /
• 2007

A performance specification states requirements in terms of the required results, such as performance, environment and interchangeability, but without stating the methods for achieving the required results, such as material and process. therefore the performance specification is applied to attain economic efficiency and high reliability by using the advanced commercial Technology for the weapon systems and The development of performance specification and conversion into performance specification have been activated in the advanced nations. The Ministry of National Defence of Korea has regulated the specification to make performance type in developing specification and prepared performance specification guide. but the result of the development of and conversion into performance specification is very unsatisfactory, To efficiently develop and convert into performance specification, this study gives the way of market research, the creation of the performance specification from development of weapon system and part localization, the process and method for conversion of detail specification into performance specification, the use of hybrid type of performance and detail specification.

• Journal of Korean Society for Quality Management
• /
• v.41 no.3
• /
• pp.443-456
• /
• 2013

Purpose: Recently, many quality issues are aroused in military forces, such as failures in K-series weapons, combat boots defects and 40mm ammunition explosion accident. To address these problems, this paper suggests to use so called, Defense Quality Score, which is based on Taguchi loss function and developed in this research. Methods: Current defense specification states only the minimum requirement to produce the military supplies. Therefore, it is not easy to indue the continuous quality improvement of the supplies. This research suggests to use the defense quality score which measures the current status of defense supplies'quality characteristics. Results: We applied the defense quality score concept into the hot pepper sauce and long time stockpiled ammunition. We first categorize the quality characteristics into three categories, then assign the certain amount of score based on the importance of the characteristics. Lastly, we applied the modified Taguchi loss function to calculate the achieved score of the characteristics. The perfect score is 100 and the closer to the score, the better product it indicates. Conclusions: In this research, we developed the modified Taguchi loss function to apply into the korean defense supplies. The loss function is utilized to calculate the achieved level of satisfaction of the supplies based on the defense specifications. The application of defense quality score may help to stimulate the continuous quality improvement and encourage the good will quality competition among the military providers.

• Journal of Advanced Navigation Technology
• /
• v.22 no.5
• /
• pp.351-358
• /
• 2018

In this study, we propose a method of suppressing the leakage noise signal of motor assembly through the test. The motor assembly is mounted on outside of the aircraft to rotate an antenna and must satisfy RE102 requirement on MIL-STD-461F in terms of electromagnetic interference. It is confirmed by RE102 test result hat the leakage noise signal of the equipment occurs due to external influx through the power and control cable and rotation of the motor. And it is ascertained that the part where internal/external physical shielding is difficult to rotate is the leakage path. To reduce the leakage noise signal, the electrical ground reinforcement and the electric shielding structure considering the operation of the equipment is applied and it is verified that the requirement is satisfied. Finally, we verified that required specification are met by applying circular corrugated choke with interlocking shapes and conductive grease to the noise leakage path.

• Journal of the Korean Society for Heat Treatment
• /
• v.8 no.1
• /
• pp.53-64
• /
• 1995

A study was made to characterize the microstructures and mechanical properties of the base metal and the heat-affected zone(HAZ) in Cu-bearing HSLA-100 steel. The Gleeble thermal/mechanical simulator was used to simulated the weld HAZ. The relationship between microstructure and toughness of HAZ was studied by impact test, O. M, SEM, TEM, and DSC. The toughness requirement of military specification value was met in all test temperatures for the base metal. The decrease of HAZ toughness comparing to base plate is ascribed to the coarsed-grain and the formation of bainite. Obliquely sectioned Charpy specimens show that secondary crack propagate easily along bainite lath. Improved toughness(240J) at HAZ of $Tp_2=950^{\circ}C$ is due to the fine grain, and reasonable toughness(160~00J) in the intercritical reheated HZA is achieved by the addition of small amount of carbon which affects the formation of "M-A". Cu precipitated during ageing for increasing the strength of base metal is dissolved during single thermal cycle to $1,350^{\circ}C$ and is precipitated little on cooling and heating during subsequent weld thermal cycle. Thus, the decrease of toughness does not occur owing to the precipitation of Cu.

• Journal of the Korea Society for Simulation
• /
• v.19 no.4
• /
• pp.249-259
• /
• 2010

Synthetic environment data used in defense M&S fields, which came from various organization and source, are consumed and managed by their own native database system in distributed environment. But to manage these diverse data while interoperation in HLA/RTI environment, neutral synthetic environment data model is necessary to transmit the data between native database. By the support of DMSO, SEDRIS was developed to achieve this requirement and this specification guarantees loss-less data representation, interchange and interoperability. In this research, to use SEDRIS as a standard simulation database, base research, visualization for validation, data interchange experiment through test-bed was done. This paper shows each research case, result and future research direction, to propose standardized SEDRIS usage process.

• Composites Research
• /
• v.31 no.3
• /
• pp.104-110
• /
• 2018

This study is to propose the structural design and analysis procedure about composite blade and tower of vertical axis wind turbine technology. In this study, structural design of tower for vertical axis wind turbine was performed after vertical blade design and manufacturing. The structural design requirement and specification of blade and tower was investigated. After tower of structural design, the structural analysis of the tower was conducted by the finite element method. It was performed that the stress, deformation and natural frequency analysis at the applied loading. The design modification of tower configuration was proposed by structural analysis. It was confirmed that the final designed tower structure is safety through the structural analysis.

• Journal of Aerospace System Engineering
• /
• v.10 no.1
• /
• pp.51-58
• /
• 2016

In this paper, we present some results on No-failure accelerated life test of aerial vehicle for reliability demonstration. The design of general accelerated life test consists of the three phases: 1) Estimating normal life test time of a single product from Weibull distribution model; 2) Determining the acceleration factor (AF) by utilizing the relation between the life of mechanical components and the applied torque; 3) Calculating the accelerated life test time, which comes from dividing the estimated normal life test time into AF. Then, we applied the calculated life test time to the real reliability test of the flap actuating system, while considering the requirement specification for mechanical components and operating environment of the actuation system. Real experimental processes and results are presented to validate the theory.