• Journal of the Korean Society of Propulsion Engineers
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• v.26 no.4
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• pp.64-71
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• 2022

For the development of an improved upper-stage engine, research on a staged combustion cycle liquid rocket engine is in progress. A cold flow test, ignition test, and combustion test plans were established and performed to develop reignition combustion technology. In order to solve the problem of purge gas flowing into the fuel line, which may cause cavitation in the turbo pump during reignition, the test results of each stage were analyzed. Based on the analysis results, the purge gas inflow problem was solved by reducing the overlapping time between the operation of the bubble removal valve and the opening of the purge valve and the engine fuel valve. Based on this, the reignition combustion test was successfully performed.

• Journal of Aerospace System Engineering
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• v.10 no.4
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• pp.84-89
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• 2016

Electronic Warfare (EW) is the mission area responsible to establish and maintain a favorable position in the electromagnetic domain. Testing and Evaluation of EW devices on modern military aircraft to pursue this critical mission area require the use of a wide range of techniques and analytical methods to assure users of the readiness of EW system to meet the challenge of a combat environment. This paper is intended as an introductory text dedicated to EW systems (especially RWR, CMDS) test and evaluation techniques and will serve experienced engineers and program managers, as well as novice engineers, as a concise reference for EW systems' test and evaluation processes and testing resources.

• Journal of the Korea Institute of Military Science and Technology
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• v.27 no.3
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• pp.375-386
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• 2024

Autonomous weapon systems act according to artificial intelligence-based judgement based on recognition through various sensors. Test and evaluation for various scenarios is required depending on the characteristics that artificial intelligence-based judgement is made. As a part of this approach, this paper proposed a LiDAR point cloud augmentation method for mixed-reality based test and evaluation. The augmentation process is achieved by mixing real and virtual LiDAR signals based on the virtual LiDAR synchronized with the pose of the autonomous weapon system. For realistic augmentation of test and evaluation purposes, appropriate intensity values were inserted when generating a point cloud of a virtual object and its validity was verified. In addition, when mixing the generated point cloud of the virtual object with the real point cloud, the proposed method enhances realism by considering the occlusion phenomenon caused by the insertion of the virtual object.

• 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 the Korean Society of Propulsion Engineers
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• v.22 no.2
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• pp.125-130
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• 2018

The technology development of a high performance upper stage engine for a GEO(GEostationary Orbit) KSLV(Korea Space Launch Vehicle) is undergoing in Korea Aerospace Research Institute. KSLV is composed of an open cycle engine with gas generator, which is for a low orbit launch vehicle. However the future GEO launch vehicle requires a high performance upper stage engine with a high specific impulse. The staged combustion cycle engine is necessary for this mission. In this paper, current progress and future plan for staged combustion cycle engine development is described.

• Journal of the Korean Society of Propulsion Engineers
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• v.24 no.6
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• pp.120-125
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• 2020

75 tonf liquid rocket engine combustion test was performed at Naro space center Engine Combustion Test Facility for KSLV-II. A gradual pressure drop was observed during off-design combustion test turbopump inlet condition using cooled kerosene at 271 K. It was found that the water content inside kerosene could cause pressure drop at 40 ㎛ grade filter through the water contests analysis of kerosene, kerosene cooling test and dehydration of kerosene.

• Journal of Industrial Technology
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• v.27 no.B
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• pp.59-64
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• 2007

This study introduces an environmental noise evaluation procedure and results for a wind turbine (W/T) system. Test and evaluation are required by the international standard IEC 61400-11 in the aspect of environmental effect. Test and evaluation are performed on U-50 WT model which is first developed by the domestic W/T manufacturer. W/T test model is under operation in Daekwanryung wind test site. An integrated monitoring system in the test site is utilized for the evaluation. With the noise signal, meteorological data and W/T operational data are monitored in real time by the integrated monitoring system using LabVIEW. From the measured noise data, acoustic power level are estimated and compared with those of other similar size WT under the wind speeds required by international standard.

• Journal of the Korean Society of Systems Engineering
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• v.20 no.1
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• pp.16-25
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• 2024

By deriving the limitations of the test evaluation, it was intended to suggest a plan to improve the test evaluation system for the appropriateness of the number of ship crews according to the design and construction of troops-saving ships. Currently, the number of crew members by ship type is confirmed and specified in the ROC(Operation Requirement Performance) in the early stages of design, such as conceptual design, but there is a limit to testing and evaluating the appropriateness of ensuring reliability of combat performance.

• Journal of the Korean Society of Systems Engineering
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• v.7 no.2
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• pp.7-11
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• 2011

A high-speed railway system represents a typical example of large-scale multi-disciplinary system, consisting of subsystems such as rolling-stock, electrical hardware, electronics, control, information, communication, civil technology etc. The system design and acquisition data of the large-scale system must be the subject under strict configuration control and management. Systems engineering technology development project for Korea next generation High-speed Electric Multiple Unit (HEMU) system in progress is a national large system development project that is not only a large-size and complex but also multi-disciplinary in nature. Therefore, all stakeholders must understand and share the functional and performance requirements of HEMU throughout its life-cycle phases. Also in the test and evaluation phase, all systems requirements must be verified. In 2011, the prototype train manufacturing will be completed. It will do test run on the commercial line and all systems requirements are verified until 2012. For the system verification, the test and evaluation process have to be established before the test trial run. Using a systems engineering tool, the system design database(SDD) with requirements traceability and development process management in the course of the development have to be established. This paper represents the test and evaluation process development based on the SEMP(Systems Engineering Management Plan) developed in the design stage. The test and evaluation process is refined and updated in comparison to the design stage one. The test and evaluation process consists of procedure, test and evaluation method and schedule. So through this process, it is defined that each systems requirements is verified on which test and about what time.

• IE interfaces
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• v.23 no.1
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• pp.78-88
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• 2010

In this paper we develop a model for the performance evaluation of defense R&D test development projects based on analytic hierarchy process. First, evaluation indicators are collected through the related literature survey and a delphi inquiry method. Second, stepwise multiple linear regression is used for developing a hierarchical structure for analytic hierarchy process in the evaluation model, which can make the selected evaluation indicators of the hierarchical structure independent. Also we verify the effectiveness of proposed indicators of the performance evaluation by comparing with the existing evaluation indicators. The developed indicators for the performance evaluation is more reasonable and practical than the previous indicators on defense R&D test development projects.