• Nuclear Engineering and Technology
• /
• v.51 no.1
• /
• pp.31-44
• /
• 2019

This study simulated a control rod assembly (CRA), which is a part of reactor shutdown systems, in immersed and fluid flow conditions. The CRA was inserted into the reactor core within a predetermined time limit under normal and abnormal operating conditions, and the CRA (which consists of complex geometric shapes) drop behavior is numerically modeled for simulation. A full-scale prototype CRA drop test is established under room temperature and water-fluid conditions for verification and validation. This paper describes the details of the numerical modeling and analysis results of the several conditions. Results from the developed numerical simulation code are compared with the test results to verify the numerical model and developed computer code. The developed code is in very good agreement with the test results and this numerical analysis model and method may replace the experimental and CFD method to predict the drop behavior of CRA.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.17 no.4
• /
• pp.430-435
• /
• 2014

This paper presents the case study of the airworthiness certification for the flight control system of tactical UAV. Airworthiness regulations for flight characteristics and design and construction based on the STANAG 4671 are selected, and safety assessment is performed. Stall protection on wing level and turning flight criteria, and flap interconnection system failures were analyzed and applied to the flight control system design. The Hardware-in-the-loop simulation including math model, integrated system verification and validation test and failure mode and effects test were also performed and they are used to validate the means of compliance of the proposed airworthiness.

• Journal of Institute of Control, Robotics and Systems
• /
• v.16 no.9
• /
• pp.905-912
• /
• 2010

Modern version of advanced supersonic fighter have ATCS (Automatic Thrust Control System) to maximum flight safety, fuel efficiency and mission capability the integrated advanced autopilot system such as TFS (Terrain Following System), GCAS (Ground Collision Avoidance System) and AARS (Automatic Attitude Recovery System) and etc. This paper addresses the design and verification of ATCS based on advanced supersonic trainer in HILS (Hardware In the Loop Simulator) with minimum hardware modification to reduce of development cost and maintain of system reliability. The function of ATCS is consisted of target speed hold mode in UA (Up and Away) and angle of attack hold mode in PA (Power Approach). The real-time pilot evaluation reveals that pilot workload is minimized in cruise and approach flight stage by ATCS.

• Journal of Intelligence and Information Systems
• /
• v.9 no.2
• /
• pp.65-85
• /
• 2003

Any ERP system pushes a company toward full process integration and solves the fragmentation of information. However, the tight process integration can propagate and magnify mistakes made in one department into the other departments in real time. Thus, it can be posited that a central support system for the coordination can help ERP users and administrators dig out problems, take care of tedious validation and verification, and maintain process integration of ERP with great consistency. This paper proposes an agent-based ERP operations support system (EOSS) that aims at achieving and maintaining process integration of ERP at the highest level possible. With EOSS, the process integrity is monitored, with anomalies prevented as early as possible and repaired as precisely as possible.

• Journal of Ship and Ocean Technology
• /
• v.8 no.1
• /
• pp.10-30
• /
• 2004

High-fidelity RANS simulations are presented for a ducted marine propulsor, including verification ＆ validation (V＆V) using available experimental fluid dynamics (EFD) data. CFDSHIP-IOWA is used with $\textsc{k}-\omega$ turbulence model and extensions for relative rotating coordinate system and Chimera overset grids. The mesh interpolation code PEGASUS is used for the exchange of the flow information between the overset grids. Intervals V＆V for thrust, torque, and profile averaged radial velocity just downstream of rotor tip are reasonable in comparison with previous results. Flow pattern displays interaction and merging of tip-leakage and trailing edge vortices. In interaction region, multiple peaks and vorticity are smaller, whereas in merging region, better agreement with EFD. Tip-leakage vortex core position, size, circulation, and cavitation patterns for $\sigma=5$ also show a good agreement with EFD, although vortex core size is larger and circulation in interaction region is smaller.

• Journal of the Korean Society of Systems Engineering
• /
• v.16 no.2
• /
• pp.16-26
• /
• 2020

Improving operator performance in complex and time-critical situations is critical to maintain plant safety and operability. These situations require quick detection, diagnosis, and mitigation actions to recover from the root cause of failure. One of the key challenges for operators in nuclear power plants is information management and following the control procedures and instructions. Nowadays Digital Twin technology can be used for analyzing and fast detection of failures and transient situations with the recommender system to provide the operator or maintenance engineer with recommended action to be carried out. Systems engineering approach (SE) is used in developing a digital twin for the CEDM system to support operator actions when there is a misalignment in the control element assembly group. Systems engineering is introduced for identifying the requirements, operational concept, and associated verification and validation steps required in the development process. The system developed by using a machine learning algorithm with a text mining technique to extract the required actions from limiting conditions for operations (LCO) or procedures that represent certain tasks.

• International conference on construction engineering and project management
• /
• 2007.03a
• /
• pp.356-365
• /
• 2007

The development in the design process is usually based on the choice of a method for designing the system, in which this method is frequently faced with tightening environmental requirements, reducing development cycle times and growing complexity. To tackle such factors, the paper proposes a comprehensive approach focusing on applying systems engineering approach to the building design support. In particular, this paper addresses all capabilities of using some available systems engineering standards (like EIA-632) in the design process. Then, a methodological approach is proposed for the practice of requirements engineering by applying quality assessment and control to design in early phase. The paradigm used, here is to extend and particularly to adapt the work carried out in military and space systems to modern building services by taking into account the semantics of buildings in terms of different engineering fields and architecture issues.

• KIEAE Journal
• /
• v.14 no.1
• /
• pp.39-48
• /
• 2014

In the previous test, the verification of the standard floor impact source was carried out comparing the physical characteristics with living impact sources. The result was appeared the validation of the standard impact source was very low because of differences of physical characteristics. This study aims to evaluate annoyance and loudness of standard impact source which is used for the measurement of floor impact sound, and to compare the annoyance and loudness of living impact sources which are produced in real life. The impact sources considered are tapping machine, tire and impact ball as standard sources, and nine real sources which were chosen from the existing researches. The result showed differences of annoyance and loudness between standard impact sources and living impact sources, which means the standard impact sources may rate the performance of floor system inappropriately. In the future, the rating method should be examined how the standard impact sources are similar with real sources in the point of rating the performance of floor system.

• Journal of Industrial Technology
• /
• v.37 no.1
• /
• pp.5-11
• /
• 2017

The purpose of this research is to propose an efficient loop line operation plan for customer transportation in a new theme park. Based on the expected customer arrivals, customer loading/unloading methods, and scheduled/non-scheduled departure schemes, movement time between stations etc., we have performed indepth analyses and derived the best optimal policy. Our results show that, over all, the operation with separate loading/unloading doors and scheduled departure is preferred to the other options. We then derived the optimal number of trains and cars meeting minimal customer unsatisfaction with low cost for each season.

• Journal of computational fluids engineering
• /
• v.21 no.3
• /
• pp.89-97
• /
• 2016

In this study, direct code coupling, in which two codes share a single flow field, was conducted using 3-dimensional high resolution thermal hydraulics code, CUPID and 1-dimensional system analysis code, MARS. This approach provide the merit to use versatile capability of MARS for nuclear power plants and 3-dimensional T/H analysis capability of CUPID. Numerical Method to directly couple CUPID and MARS was described in this paper. The straight flow and manometer flow oscillation were calculated to verify conservation of coupled CUPID/MARS code in mass, momentum, and energy. This verification calculations indicates that the CUPID/MARS is coupled appropriately in numerical aspect and the coupled code can be applied to nuclear reactor thermal hydraulics after validation against integral transient experiments.