• Proceedings of the KSR Conference
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• 2003.05a
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• pp.519-524
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• 2003

Systems engineering test and evaluation technology development program for (Korea) Express Tilting Train(TTX) system in progress is a national large system development program that is not only a large-size and complex but also multi-disciplinary in nature. For the TTX test and evaluation technology development, verification requirements that could verify system function and performance, should be derived from system specification. Hereafter, this could be listed as items of test. System engineering process establish traceability between items of test and system requirements. These tasks could be accomplished by the schema. Using the Core, a system engineering tool, TTX program could be database and similar other system could be developed effectively and efficiency

• Journal of Korean Institute of Industrial Engineers
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• v.18 no.2
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• pp.99-107
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• 1992

Both simulation and expert systems are popular ways to solve complex and hard problems. However, the results of the simulation, which include a large amount of valuable information as a good knowledge source, are not used efficiently. Furthermore, the development of the expert systems can fail because there is no expert or an expert is not available. A new Simulation-Based Expert System(SIMBES) paradigm has been constructed to overcome these problems. It consists of simulator, feature extractor, machine learning system, performance evaluator and Knowledge-Based Expert System(KBES). A SIMBES was implemented for an existing schedule-based MRP system in Smalltalk/V to show how this paradigm works and experimented for a large number of jobs. The KBES and the existing system produced better schedules for 72 percent and 28 percent of the jobs, respectively.

• Advances in aircraft and spacecraft science
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• v.8 no.1
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• pp.69-85
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• 2021

A modified fuzzy mechanical control of large-scale multiple time delayed dynamic systems in states is considered in this paper. To do this, at the first level, a two-step strategy is proposed to divide a large system into several interconnected subsystems. As a modified fuzzy control command, the next was received as feedback theory based on the energetic function and the LMI optimal stability criteria which allow researchers to solve this problem and have the whole system in asymptotically stability. Modeling the Fisher equation and the temperature gauge for high-speed aircraft and spacecraft shows that the calculation method is efficient.

• Journal of the Korean Institute of Rural Architecture
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• v.23 no.3
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• pp.9-18
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• 2021

This paper conducted a survey of residents and public officials for the projects to make smart-city plans of Geumsan-gun. In introduction, several domestic and foreign cases related to smart-city projects were Investigated. To initiate the smart-city project of Geumsan-gun, the local status of Geumsan-gun was investigated regarding various aspects of natural, social, urban environment and smart-city facilities. The results of this survey are as follows: Overall, more than half of survey respondents said they had satisfaction of their housing quality. Several problems in their residence areas, such as insufficient welfare systems, shortage of parking spaces, industrial infrastructure, were reported. Meanwhile, the survey result indicated that tourism and leisure facilities, health care support systems, industries promote the economy and job market of the area. An interview with public official is also important to select the relevant meaningful projects and regional issues. Three models for each spatial unit were proposed in Geumsan-gun based on the natural, agricultural, and geographical environment. In result, the three smart-city models are categorized as urban type(large area), complex city type(medium area), and smart village type(small area)

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.18 no.12
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• pp.67-72
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• 2019

In manufacturing sites that process and produce parts in large quantities for the automotive and electronics industries, users require the reducing of costs and shortened delivery times. To meet these demands, an increase in the number of processes and an decrease in assembly times need to be addressed. Gantry loaders currently on the market in Korea are mostly used for processing lightweight and simple shapes and are not suitable for conveying and processing complex shapes such as automobile engines and aircraft parts. This makes it difficult to mount the material in place. This study aims to smoothen the transportation of complex shapes through the development of jigs and various approaches in the installation of the feed shaft by researching the gantry loader system for transporting multiple materials with complex shapes.

• Journal of the Korea Institute of Military Science and Technology
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• v.16 no.3
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• pp.260-267
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• 2013

A combat system for navy's battleship is a system of systems who supports naval indigenous operations by integrating and inter-operating many different kind of weapon and non-weapon systems, which has characteristics of large-scale complex computing system. This paper considers a characteristics of naval combat system which has been developed by domestic technology and suggests a way to improve future naval combat system in terms of computing architecture by applying commercial real-time operating system technologies. This paper also provides an evaluation criteria for combat system adaptability of real-time operating systems.

• Journal of the Korean Society of Systems Engineering
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• v.7 no.2
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• pp.39-43
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• 2011

Modern naval ships are large complex systems with the number of requirements ranges from thousands to tens of thousands. To build a quality ship, the satisfaction of the requirements should be traced. In most shipbuilding projects it is almost impossible to manage all the requirements without a proper CASE (computer aided systems engineering) tool. And for effective management of the shipbuilding project, the integrated database for technical data is very important. This paper describes how the requirements are managed, and the integrated database is built in the naval shipbuilding industry in Korea.

• Korean Journal of Agricultural and Forest Meteorology
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• v.16 no.3
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• pp.157-168
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• 2014

From a complex systems perspective, ecohydrological systems in forests may be characterized with (1) large networks of components which give rise to complex collective behaviors, (2) sophisticated information processing, and (3) adaptation through self-organization and learning processes. In order to demonstrate such characteristics, we applied the recently proposed 'process networks' approach to a temperate deciduous forest in Gwangneung National Arboretum in Korea. The process network analysis clearly delineated the forest ecohydrological systems as the hierarchical networks of information flows and feedback loops with various time scales among different variables. Several subsystems were identified such as synoptic subsystem (SS), atmospheric boundary layer subsystem (ABLS), biophysical subsystem (BPS), and biophysicochemical subsystem (BPCS). These subsystems were assembled/disassembled through the couplings/decouplings of feedback loops to form/deform newly aggregated subsystems (e.g., regional subsystem) - an evidence for self-organizing processes of a complex system. Our results imply that, despite natural and human disturbances, ecosystems grow and develop through self-organization while maintaining dynamic equilibrium, thereby continuously adapting to environmental changes. Ecosystem integrity is preserved when the system's self-organizing processes are preserved, something that happens naturally if we maintain the context for self-organization. From this perspective, the process networks approach makes sense.

• Journal of Mechanical Science and Technology
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• v.19 no.spc1
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• pp.388-394
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• 2005

Recently, the authors have developed a method for real-time dynamics of multibody systems, which combines a semi-recursive formulation to derive the equations of motion in dependent relative coordinates, along with an augmented Lagrangian technique to impose the loop closure conditions. The following numerical integration procedures, which can be grouped into the so-called structural integrators, were tested : trapezoidal rule, Newmark dissipative schemes, HHT rule, and the Generalized-${\alpha}$ family. It was shown that, for large multi body systems, Newmark dissipative was the best election since, provided that the adequate parameters were chosen, excellent behavior was achieved in terms of efficiency and robustness with acceptable levels of accuracy. In the present paper, the performance of the described method in combination with another group of integrators, the Implicit Runge-Kutta family (IRK), is analyzed. The purpose is to clarify which kind of IRK algorithms can be more suitable for real-time applications, and to see whether they can be competitive with the already tested structural family of integrators. The final objective of the work is to provide some practical criteria for those interested in achieving real-time performance for large and complex multibody systems.

• Proceedings of the KSR Conference
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• 2011.05a
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• pp.1604-1611
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• 2011

Light Rail Transit(LRT) is a large scale complex system which combines rolling stocks, power supply, signal communication, tracks & stations, and hundreds of billions of wons per project are spent for construction. Therefore efficient integration of sub-systems is very important. The systems engineering is a good method to reduce the cost and risk of LRT project. In this paper, we introduce a research plan on the application of systems engineering to LRT project. We, Korea Railroad Research Institute(KRRI), launched a research program with 4 companies, which is support by the governmen and project period is 4.5 years. Main research topic is to develop the technology for the application of systems engineering technical process to LRT project based on ISO/IEC 15288.