• Journal of the Korea Institute of Military Science and Technology
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• v.17 no.3
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• pp.296-303
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• 2014

This paper describes the simplified simulation method of the wire-guided underwater test body with natural supercavitation. In this paper, the simulation based model of the wire-guided underwater body with natural supercavitation is proposed by using preceding research and commercial flow-analysis software. By using the model, the 1-dimensional wire-guided body motion in natural supercavitation can be solved very fast with reliability. The suggested model is validated by the comparison of simulation results with experimental data.

• Journal of the Korea Institute of Military Science and Technology
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• v.17 no.6
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• pp.844-852
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• 2014

PBX simulant is known to exhibit highly nonlinear behaviors of deformation such as the stress softening, hysteresis under cyclic loading, residual strain after unloading, and aging. This paper proposes a new pseudo-elastic model for PBX simulant considering stress softening and residual strain. Uniaxial loading and unloading tests at quasi-static states were carried out in order to obtain the mechanical properties of the PBX simulants. And then the Dorfmann-Ogden model is modified to make it consistent with the test result of PBX simulants. Prediction with the new model shows a good correspondence to the experimental data demonstrating that the model properly describes stress softening and residual strain of PBX simulants.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.9 no.6
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• pp.566-572
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• 2016

Software Reliability implemented in software development is one of the most important issues. In finite failure NHPP software reliability models for software failure analysis, the hazard function that means a failure rate may have constant independently for failure time, non-increasing or non-decreasing pattern. In this study, software development cost analysis considering the variable shape parameter of Erlang distribution as the failure life distribution in the software product testing process was studied. The software failure model was applied finite failure Non-Homogeneous Poisson Procedure and the parameters approximation using maximum likelihood estimation was accompanied. Thus, this paper was presented comparative analysis by applying a software failure time data to the software, considering the shape parameter of Erlang distribution for development cost model analysis. When compared to the cost curve in accordance with the shape parameter, the model of smaller shape can be seen that the optimal software release time delay and more cost. Through this study, it is thought that it can serve as a preliminary information which can basically help the software developers to search for development cost according to software shape parameters.

• Journal of Environmental Impact Assessment
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• v.15 no.6
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• pp.385-394
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• 2006

Land resources should be managed not only for human utilizations but also for environmental preservation. Based on that, environmental capacity should be estimated in both environmental and developmental ways. This study was performed for developing an estimation model for relative environmental capacity, considering both Development Tolerance Index(DTI), which shows environmental and ecological conservation value and is based on national environmental assessment indicators of the Korea Ministry of Environment, and Development Attractiveness Index(DAI), which shows topographical characteristics and geographical accessibility. The relative environmental capacity in this study can be helpful to coping with the conflict in planning and managing the use of land resources. The relative environmental capacity in this study, however, did not include either environmental or ecological sensitivity of land resources. This limitation should be solved through further research.

• The Journal of the Korea Contents Association
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• v.9 no.2
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• pp.326-338
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• 2009

In this paper, we argue that characteristics of ubiquitous business are different from those of e-business or m-business. We have developed a u-business model development framework incorporating the concept of value co-creation experiences, which is a core of the ubiquitous business paradigm. The framework of u-business model development presented in this paper consists of eight steps such as defining of domain, discovery of opportunity nucleus, defining of potential co-creation experience environment, deriving candidates of u-business services, selecting u-business killer services, defining value propositions of u-business killer services, defining u-business killer service offerings, and drawing a resource map of u-business killer services. The proposed u-business model development framework offers useful guidelines for practitioners to develop successful u-business models under a ubiquitous business paradigm.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.21 no.6
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• pp.527-533
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• 2008

This paper proposes a product data model and associated process for CAE activities in context of integrated product development. The data model and process enable Product Lifecycle Management(PLM) systems to integrate currently separated CAE activities into the main product development process. The product view concept in the proposed product data model supports independent CAE activities including analysis of various alternatives based on shared product structures with design departments and seamless translation of the CAE result to design product views. The proposed model is validated through an implementation of a prototype PLM system that can integrate and synchronize CAE process with the company-wide product development process.

• Journal of the Korea Society of Computer and Information
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• v.27 no.5
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• pp.109-116
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• 2022

Recently, a model-based development method centered on highly readable and standardized UML (Unified Modeling Language) models has been applied to solve unclear communications in large-scale software development. However, it is difficult to apply consistent UML models depending on software developers' proficiency, understanding of models and modeling tools. In this paper, we propose a method for developing a Model Verification System to apply an consistent UML model to software development. Then, the developed Model Verification System is partially applied to the Naval Combat System Software development to prove its function. The Model Verification System provides automatic verification of models created by developers according to domain characteristics. If the Model Verification System proposed in this paper is used, It has the advantage of being able to apply the consistent UML model more easily to Naval Combat System Software Development.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.12 no.3
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• pp.59-71
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• 2009

The goals of this study were to development Natural Ecosystem Value Assessment Model, to suggest the practical applicability of the Natural Ecosystem value assessment for development areas, and to assess natural ecosystem quantitatively using GIS. The Model can evaluate Natural Ecosystem Value between before and after land developments. To select indicators for the model, we conducted the literature reviews. and six indicators and the standard of evaluation had been developed through the expert interviews and literature reviews. the relative importance of the evaluation index throught two times expert questionnaires was found out. the Natural Ecosystem Value Assessment Model has been established, The results demonstrate that although the suggested six indicators are arranged by priority, to maintain quantitative and qualitative the natural ecosystem value, all indicators are desirable to be maintained complementarily. The findings of this study suggest that the natural ecosystem value assessment model appears to be effective an assessment for damaged natural environment value and possible to assign a score value. Also, this model can be applied to research areas and has implications to help maintain the natural ecosystem in land development districts.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.12
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• pp.182-191
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• 2004

This study is focused on the development of a child human model, which is composed of skin, skeleton, joints and muscle, etc. The dimension of child outer skin is referred to anthropometric data from KRISS (Korea Research Institute of Standards and Science). The positions of joint and mass properties of body segments are calculated from ATB(Articulated Total Body) program, GEBOD. The properties of bones and muscles are obtained by the way of scaling from adult human model. To verify the developed human model, ROM simulation and sled test is conducted. Developed human model can be effectively applied to the evaluation of human injury in crash situation and development of child restraint system. The explicit finite element program $PAM-CRASH^TM$ was used to simulate six-year old child human model.

• Journal of the Korea Institute of Military Science and Technology
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• v.17 no.6
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• pp.861-867
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• 2014

In the present study, the flow around a circular cylinder at $Re=3.6{\time}10^6$ is numerically simulated using URANS approach. The objective of this study is to evaluate the turbulence models(Realizable k-${\varepsilon}$, RNG k-${\varepsilon}$) through the prediction of the unsteady flow characteristics around the cylinder. The time-averaged drag coefficients and vortex shedding phenomenon in the wake region are compared to available experimental data and other numerical results. The simulation with Realizable k-${\varepsilon}$ model is found to be more dissipative due to large eddy viscosity predicted in the wake region while the simulation with RNG k-${\varepsilon}$ model predicts a complex vortex shedding phenomenon with more coherent structures realistically.