• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.42 no.5
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• pp.437-443
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• 2014

Engine is one of the most important parts in a rocket for completing its mission successfully. In this paper, we provide a methodology for estimating reliability and development cost of a liquid rocket engine newly developed. To estimate reliability, a baseline engine is selected considering factors whose effects on reliability are unquantifiable. Then reliability of a baseline engine is adjusted to reflect the effect of factors that can be modeled quantitatively. Using the previous Transcost engine cost expressed in terms of mass and the number of hot firing tests, the engine development cost is reexpressed in reliability and thrust requirements. Finally, a numerical example is given to illustrate the application of the methodology to a turbopump rocket engine using staged combustion cycle with LOX/LH2 propellant.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.43 no.4
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• pp.334-340
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• 2015

Engine derating is often considered for reliability benefits because lower power operation reduces its failure probability. To be derated during operation, however, the engine must be initially overdesigned. The engine overdesign is cost effective only if reliability increased from derating is enough to offset the initial increase in the development cost caused from the overdesign. The purpose of this paper is to provide an analytical model to consider a trade-off between the engine overdesign and derating. We use a logistic regression model to explain reliability growth in the number of hot firing tests for a fixed power level. Using the Transcost model with the reliability growth model, we show that 10% overdesign of Titan rocket engine decreases its development cost by about 9% and 23% depending on the reliability requirement. We also point out that such a cost reduction depends on the fuel type a rocket uses.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2004.03a
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• pp.870-875
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• 2004

In Japan, a long-waited civil aero engine development project has been recently started by the New Energy and Industrial Technology Development Organization, NEDO. “High efficiency,” “environmentally friendliness” and “low-cost” are the key words of the target engine. The target engine is of l0000-lb thrust with project consists of three phases: Feasibility studies and market research in the first phase, FY 2003, engine component development in the second phase, FY 2004-2006, and core and full engine demonstrators in the third phase, FY 2007-2009. In league with this government/industry joint funded project, Institute of Space Technology and Aeronautics, JAXA, has initiated “Clean Engine Technology” project.

• International Journal of Advanced Culture Technology
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• v.9 no.4
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• pp.417-423
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• 2021

Recently, in the Game industries, they are increasing to use of game engines to reduce the development cost of 3D content and software. In particular, Unreal Engine provides a blueprint visual scripting function that enables software production without programming (coding). Although High-end video content can be produced, the problem is that content development is complicated and requires advanced manpower. To solve this problem, we propose an optimized VR game context process. This is because 1) a Blueprint visual script is used, 2) VR games with various interactions can be produced, 3) Non-majors in the software field (or groups) can develop advanced content. In various related industries such as defense, medical care, manufacturing, and construction, we may easily develop any game content without programming with our refined VR rhythm action game development process. We expect to reduce the development cost with the process advantages in the game industries.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.20 no.4
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• pp.348-354
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• 2010

In the beginning of vehicle development, it is difficult to define the concept of engine mounting system. With only the property of vehicle, we have to find the direction of engine mounting system. And it is important to find common mounts for several engine variation in order to reduce the cost and manage mounts efficiently. This paper introduces the software which has developed for engine mounting system analysis. And its function and usefulness are explained in paper. The examples have correlated between the analysis model and real model to raise the accuracy during development of engine mounting system are shown in paper.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.39 no.6
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• pp.576-584
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• 2011

In order to develop a launch vehicle successfully, it is important to estimate development costs accurately but it is also important to plan the annual budget. In this paper, the statistical method was utilized for cost spreading. For cost spread modeling, the suitability of the model by analyzing several statistical models was evaluated and consequently, the beta-distribution model has been selected. In this study, the validity of the annual estimation cost model was verified through the comparison of the actual development cost distribution and the estimating cost distribution of Space Shuttle Main Engine. In addition, this paper estimated the annual budget required for the development of the KSLV-II using currently allocated cost for successful development. It is anticipated that the present cost spread model can be applied to not only launch vehicle development but also other large complex system development.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.39 no.2
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• pp.203-209
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• 2015

Recently, the portion of electronic control in an engine system has been increasing with the aim of meeting the requirements of emissions and fuel efficiency of the engine system in the construction machinery industry. Correspondingly, the complexity of the engine management system (EMS) has increased. This study developed an engine HiLS system for reducing the cost and time required for function development for the EMS. The engine model for HiLS is composed of air, fuel, torque, and dynamometer models. Further, the mean value method is applied to the developed HiLS engine model. This model is validated by its application to a heavy-duty diesel engine equipped with an exhaust gas recirculation system and a turbocharger. Test results demonstrate that the model has accuracy greater than 90 and also verify the feasibility of the virtual calibration process.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.20 no.3
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• pp.235-241
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• 2010

Engine Mount plays an important role which supports engine, isolates vibration from engine and blocks the vibration from road. Development of engine mount for NVH costs great a deal. So, the cost of development being reduced, the way developed effectively engine mount using DFSS technique is proposed in this paper. CTQ(critical to quality) is vibration and parameter is dynamic stiffness of mounts. The core parameters are selected with TPA(transfer path analysis) technique. It uses design of experiments(DOE) or Taguchi Methods to optimize parameter values and reduce variation. And then, this paper shows the result of improvement for vibration in the developing vehicle.

• Transactions of the Korean Society of Automotive Engineers
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• v.22 no.5
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• pp.35-43
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• 2014

The automobile industry requires technological innovations to reduce fuel consumption with the public interest in environmental conservation in recent years. Thus, the hybrid system is applied not only to passenger cars but also commercial vehicles. The purpose of this paper is to develop engine ECU_ILS to develop commercial hybrid vehicles. In order to develop the engine and vehicle, the dynamometer and exhaust gas analyzer is needed. However, a lot of time and cost are required. In contrast, the model-based development environment that can be applied to a variety of test conditions can reduce development time. Therefore, a HILS system environment that can consider the behavior of actual vehicles for evaluation of the control logic, fuel consumption and exhaust gas is required. This engine ECU_ILS system was developed in this study, can analyze parameter such as the fuel injection rate, fuel injection time, fuel consumption and exhaust gas like the actual vehicle test using map data. Also, this system is expected to be able to analyze the characteristic of vehicle behavior and the development of peripheral device in relation to engine and vehicles. This HILS system can be used to develop control strategies of commercial hybrid vehicle systems in the future.

• Proceedings of the Korea Contents Association Conference
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• 2005.05a
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• pp.55-58
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• 2005

The existing game development way is adopting a direct engine design way. It was hard to learn game development, but it can learn the process that uses a script an abstraction. And it improves productivity and convenience anger because modeling does not do an engine directly and reduce a development cost and can solve a problem of a development human power security. The representative characteristic of this paper was able to change a development environment into an abstract script language with modeling having done an engine in the existing game development environment directly.