• Aerospace Engineering and Technology
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• v.10 no.2
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• pp.128-132
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• 2011

We can acquire the criteria of configuration tolerance on the Kick Motor system, KSLV-I upper stage propulsion system from the analysis results of the initial controllability on the KSLV-I upper stage. Also we can assign configuration tolerances on each subsystem from the configuration tolerance on the Kick Motor system. This article deals with the Kick Motor system configuration tolerance criteria and the results of configuration management on the both ground test models and flight test ones.

• Korean Journal of Computational Design and Engineering
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• v.21 no.1
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• pp.1-8
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• 2016

After 2017 years, BWMS units must be installed in the existing ship as well as the new ship by the ballast water management convention. Software tools that can help automatically searching for BWMS installation space to avoid pipes and equipment in the engine room of the existing ship will be very useful in the BWMS layout design. In this study, voxel representation of scanned data is generated first to search space efficiently. Simplified voxel models of each unit are prepared to be located in the engine room space as well. Distance between connected models is calculated through the arrangement direction and position of each model. Sums of distance between connected models are compared for the optimal configuration. It is assumed that the sum of distance between connected models depicts the pipe usage. The proposed method can save the time needed for BWMS installation design and allows optimal configuration of BWMS units.

• Journal of the Korean Mathematical Society
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• v.61 no.3
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• pp.565-602
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• 2024

We study the collective behaviors of two second-order nonlinear consensus models with a bonding force, namely the Kuramoto model and the Cucker-Smale model with inter-particle bonding force. The proposed models contain feedback control terms which induce collision avoidance and emergent consensus dynamics in a suitable framework. Through the cooperative interplays between feedback controls, initial state configuration tends to an ordered configuration asymptotically under suitable frameworks which are formulated in terms of system parameters and initial configurations. For a two-particle system on the real line, we show that the relative state tends to the preassigned value asymptotically, and we also provide several numerical examples to analyze the possible nonlinear dynamics of the proposed models, and compare them with analytical results.

• Nuclear Engineering and Technology
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• v.35 no.6
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• pp.547-555
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• 2003

Fire hazard and risk analysis at Nuclear Power Plants is implemented on the basis of the normal operational configuration. This steady configuration, however, can be changed due to the temporary displacement of equipment, electric cable and irregular movement of workers through the fire compartments when the on-line maintenance is processed during the power operation mode or the scheduled outage mode for the refueling. With the consequence of this configuration change, the fire analysis condition and the evaluation result will be different from those that were analyzed based on the steady configuration. In this context, at this paper, the general items for the reassessment are categorized when the configuration has changed. The contemporary zone models for the detail fire analysis are also illustrated for their application for each classified condition.

• Journal of the Korean Magnetic Resonance Society
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• v.2 no.1
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• pp.50-58
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• 1998

The systematic chirality investigations were made on the basic of the fact that zinc-binding tallysomycin (ZnTLMA) could have chiral centers (Zn, NC3, C6) at possible 4-, 5-, and 6-coordination models. Although our NMR data exhibit that the ligation sites are ${\beta}$-aminoalanine, ${\beta}$-hydroxyhistidine, and pyrimidine moiety, all possible coordination modes were tested out to see what kind of chiralities on NC3-C6 are favorable to each coordination mode. Tests were also made that take into account the specific configuration of functional groups, including ${\beta}$-aminoalanine, sugar ring, and ${\beta}$-hydroxyhistidine. Tests were finally extended to zinc-water binding and specific conformational studies by introducing various hydrogen bonding networks associated with the propionamide side chain and the carbamide group of mannose. Results of systematic chirality investigations exhibit that the S-S configuration of NC3-C6 is favorable to all of coordination models, but the R-S configuration, if exists at all, should have internal strain on C6 chiral center.

• Journal of Information Technology Applications and Management
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• v.14 no.2
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• pp.11-26
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• 2007

In this paper we suggest a context-driven configuration model of virtual businesses to form a business network model consisting of role-based, interaction-centered business partners. The model makes use of the subcontext concept which explicitly represents actors and interactions in virtual business (VB) context. We separate actors who have capacities on tasks in a specific kind of role and actor subcontext which models requirements in specific interaction subcontext. Three kinds of actors are defined in virtual service chains, service user, service provider, and external service supporter. Interaction subcontext models a service exchange process between two actor subcontexts with consideration of context dependencies like task and quality dependencies. Each subcontext may be modeled in the form of a situation network which consists of a finite set of situation nodes and transitions. A specific situation is given in a corresponding context network of actors and interactions. It is illustrated with a simple example.

• Journal of the military operations research society of Korea
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• v.25 no.1
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• pp.87-106
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• 1999

There are many technical datum in related with design, test & evaluation and logistic support which will be exchanged between geographically isolated units and heterogeneous hardwares & softwares in developing and operating the weapon systems. The paper proposes the conceptual database schema to establish configuration management information systems in which these datum can be automatically interchanged, tracked, audited and status-accounted without errors under the various environments. The paper investigates how to identify and classify the data in accordance with document identification, task analysis, system development, logistic support, system test & evaluation and data management. Furthermore, the investigation includes drawing the subject areas and modeling the conceptual database schema to explain the relationships between these datum. Thus, the paper results in the conceptual framework and data models of configuration management information systems, while additional customization efforts be required in applying the models to a specific weapon systems R&D.

• KIEE International Transactions on Electrophysics and Applications
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• v.4C no.5
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• pp.220-229
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• 2004

We have examined a technique of one-dimensional (1D) fluid modeling for radio-frequency Ar capacitively coupled plasmas (CCP) between unequal-sized powered and grounded electrodes. In order to simulate a practical CCP reactor configuration with a grounded side wall by the 1D model, it has been assumed that the discharge space has a conic frustum shape; the grounded electrode is larger than the powered one and the discharge space expands with the distance from the powered electrode. In this paper, we focus on how much a 1D model can approximate a 2D model and evaluate their comparisons. The plasma density calculated by the 1D model has been compared with that by a two-dimensional (2D) fluid model, and a qualitative agreement between them has been obtained. In addition, 1D and 2D calculation results for another reactor configuration with equal-sized electrodes have also been presented together for comparison. In the discussion, four CCP models, which are 1D and 2D models with symmetric and asymmetric geometries, are compared with each other and the DC self-bias voltage has been focused on as a characteristic property that reflects the unequal electrode surface areas. Reactor configuration and experimental parameters, which the self-bias depends on, have been investigated to develop the ID modeling for reactor geometry with unequal-sized electrodes.

• International Journal of Aeronautical and Space Sciences
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• v.16 no.1
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• pp.8-18
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• 2015

A numerical simulation for a nonslender BWB UCAV configuration with a rounded leading edge and span of 1.0 m was performed to analyze its aerodynamic characteristics. Numerical results were compared with experimental data obtained at a free stream velocity of 50 m/s and at angles of attack from -4 to $26^{\circ}$. The Reynolds number, based on the mean chord length, is $1.25{\times}106$. 3D multi-block hexahedral grids are used to guarantee good grid quality and to efficiently resolve the boundary layer. Menter's shear stress transport model and two transition models (${\gamma}-Re_{\theta}$ model and ${\gamma}$ model) were used to assess the effect of the laminar/turbulent transition on the flow characteristics. Aerodynamic coefficients, such as drag, lift, and the pitching moment, were compared with experimental data. Drag and lift coefficients of the UCAV were predicted well while the pitching moment coefficient was underpredicted at high angles of attack and influenced strongly by the selected turbulent models. After assessing the pressure distribution, skin friction lines and velocity field around UCAV configuration, it was found that the transition effect should be considered in the prediction of aerodynamic characteristics of vortical flow fields.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.16 no.6
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• pp.35-40
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• 2017

The aerodynamic performance of airplane is different according to the configuration of landing gear. As the drag becomes different according to this configuration, the flow stream of air must be smooth at taking off and landing. In this study, the configuration of landing gear was designed each in order to enhance the energy efficiency of airplane. Five models were compared in total at analysis. The magnitudes of drag and pressure became different and the air pressure of wake were changed due to the configuration. So, the air pressure due to the flow velocity and the air resistance happening at the rear can be estimated according to the configuration of landing gear. It is thought to improve the performance of airplane through the result of this study.