• International Journal of Aeronautical and Space Sciences
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• v.16 no.4
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• pp.624-635
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• 2015

Design space exploration has been much neglected in aircraft conceptual design phase, which often leads to a waste of time and cost in design, manufacture and operation process. It is necessary to explore design space based on operational system-of-systems (SoS) simulation during the early phase for a competitive design. This paper proposes a methodology to analyze aircraft performance parameters in four steps: combination of parameters, object analysis, operational simulation, and key-parameters analysis. Meanwhile, the design space of an unmanned aerial vehicle applied in earthquake search and rescue SoS is explored based on this methodology. The results show that applying SoS simulation into design phase has important reference value for designers on aircraft conceptual design.

• Journal of the Korean Operations Research and Management Science Society
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• v.21 no.3
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• pp.127-141
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• 1996

In this paper, we propose a 7-phase life cycle model which applies to Computer Integrated Manufacturing systems. The model emphasizes product design and manufacturing design activities of CIM to secure the critical success factors of CIM systems such as high quality, adaptability, productivity, and flexibility. It is argued that the product design aspect would be divided into three phases-conceptual design, embodiment design, and detialed design. The conceptual design phase is to build a conceptual model of the product based on requirements and specifications which reflect "the voice of the customer". THe embodiment design phase utilizes specific design tools such as DFM, CAE, and CAD, and results in a concrete model of the product and parts. The detailed design phase is to crete a working prototype of the product and design tools such as DFA. CAD and CAM are employed in this phase. The output of the product design activity is to be the input for the manufacturing design activity. Using the proposed model, one can effectively and efficiently manufacture a high-quality, low-cost product with short delivery time, and above all achieve customer'ssatisfaction.isfaction.

• Proceedings of the Korea Society of Design Studies Conference
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• 2001.10a
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• pp.57.2-57
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• 2001

• Journal of the Korea Institute of Military Science and Technology
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• v.9 no.3
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• pp.56-65
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• 2006

It is well known and widely accepted that the conceptual design is the most influential step in the design process of a product or a system and that about 75% of the life cycle cost is committed as the results of this stage. The purpose of this paper is to present and demonstrate the step of ICDM(Integrated, Customer Driven, Conceptual Design Method) for the development of a ground launcher system, TEL(Transporter, Erector and Launcher). The results of the study show the effectiveness of the method during the conceptual design phase of new complex systems or high-tech products.

• Nuclear Engineering and Technology
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• v.45 no.6
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• pp.721-730
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• 2013

Within the framework of the ASTRID project, core design studies are being conducted by the CEA with support from AREVA and EDF. The pre-conceptual design studies are being conducted in accordance with the GEN IV reactor objectives, particularly in terms of improving safety. This involves limiting the consequences of 1) a hypothetical control rod withdrawal accident (by minimizing the core reactivity loss during the irradiation cycle), and 2) an hypothetical loss-of-flow accident (by reducing the sodium void worth). Two types of cores are being studied for the ASTRID project. The first is based on a 'large pin/small spacing wire' concept derived from the SFR V2b, while the other is based on an innovative CFV design. A distinctive feature of the CFV core is its negative sodium void worth. In 2011, the evaluation of a preliminary version (v1) of this CFV core for ASTRID underlined its potential capacity to improve the prevention of severe accidents. An improved version of the ASTRID CFV core (v2) was proposed in 2012 to comply with all the control rod withdrawal criteria, while increasing safety margins for all unprotected-loss-of-flow (ULOF) transients and improving the general design. This paper describes the CFV v2 design options and reports on the progress of the studies at the end of pre-conceptual design phase 1 concerning: - Core performance, - Intrinsic behavior during unprotected transients, - Simulation of severe accident scenarios, - Qualification requirements. The paper also specifies the open options for the materials, sub-assemblies, absorbers, and core monitoring that will continue to be studied during the conceptual design phase.

• Journal of Korean Association for Spatial Structures
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• v.5 no.3 s.17
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• pp.75-82
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• 2005

The conceptual structural design consists of selecting structural material and form of the building, producing a preliminary dimensional layout. The information such as height of the building use, typical live load, wind velocity, design acceleration, maximum lateral deflection, span, story height is a important factor in conceptual design phase. In this case, the knowledge solutions for past similar problems cam be used in the process of defining and finding a solution to the design problems. In this paper, the conceptual structural design method using case-based reasoning which is intended to assist engineers in the conceptual phase of the structural design of tall buildings is introduced. Inductive retrieval method and nearest-neighbor retrieval method are used for selecting structural system and similar design case, respectively.

• Proceedings of the KIEE Conference
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• 1998.07a
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• pp.94-97
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• 1998

The conceptual design of integrated three phase superconducting fault current limiter (SFCL) is presented. And through simulation of power system where this SFCL is installed, the characteristics of this SFCL is analyzed. It is like three-phase transformer. So it has the same characteristics with inductive single phase SFCL. But it has more merits than single phase SFCL. Differently to single phase SFCL, integrated three phase SFCL induces impedance at all phase by any single phase fault to protect the power system more safely.

• Journal of the Korean Society of Safety
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• v.34 no.3
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• pp.102-110
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• 2019

This paper describes the work and results of the preliminary Probabilistic Safety Assessment (PSA) for a research reactor in the design phase. This preliminary PSA was undertaken to assess the level of safety for the design of a research reactor and to evaluate whether it is probabilistically safe to operate and reliable to use. The scope of the PSA described here is a Level 1 PSA which addresses the risks associated with core damage. After reviewing the documents and its conceptual design, eight typical initiating events are selected regarding internal events during the normal operation of the reactor. Simple fault tree models for the PSA are developed instead of the detailed model at this conceptual design stage. A total of 32 core damage accident sequences for an internal event analysis were identified and quantified using the AIMS-PSA. LOCA-I has a dominant contribution to the total CDF by a single initiating event. The CDF from the internal events of a research reactor is estimated to be 7.38E-07/year. The CDF for the representative initiating events is less than 1.0E-6/year even though conservative assumptions are used in reliability data. The conceptual design of the research reactor is designed to be sufficiently safe from the viewpoint of safety.

• Journal of the Korean Society of Systems Engineering
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• v.3 no.2
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• pp.39-48
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• 2007

In this study, an overall product design process will be presented by using the Analytic Hierarchy Process(AHP) and robust design. From the conceptual design stage, the logical methods are used to select the appropriate concepts satisfying the customer requirements and the other conditions. The next phase is the embodiment design phase in which the deterministic and robust design approach are used to obtain the improvement in product design. Typically, this approach is applied for developing the simple bookshelf design. The results show the efficient approach which can be supported to develop the new product.

• Ocean Systems Engineering
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• v.10 no.1
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• pp.111-129
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• 2020

A simplified algorithm is proposed for fast estimation of the material quantities required for the construction of rubble-mound breakwaters. The proposed algorithm is able to employ only the data available at feasibility study phase such as the maximum draught of the design ship selected to transport the cargos to the harbor despite, because at the feasibility phase, information for the planned harbor is likely to be very limited. A linear-constant waterdepth model together with a proposed section configuration for the breakwaters, which is customary for harbors, is considered to calculate the quantity of materials. The numerical simulation of the wave characteristics has been verified using the recorded wave data collected by a buoy installed near the Neka harbor in Caspian Sea waters. A case study has been also applied to four harbors to validate the proposed algorithm. The estimated weights using the proposed linear-constant and multi-linear waterdepth models were compared using the bathymetry maps and layouts of these harbors. A computer program, written in QBasic language, has been developed to simulate the wave characteristics and to estimate the material quantities needed to construct a rubble-mound breakwater. The obtained results show that taking into account the acceptable accuracies normally applied to the feasibility study and conceptual design phases, the proposed algorithm is sufficiently accurate and highly effective for the conceptual estimation of materials' quantities of breakwaters in the feasibility study phase of harbor projects.