• Advances in aircraft and spacecraft science
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• 제10권4호
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• pp.317-334
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• 2023

This paper presents a basic methodology and a set of numerical tools for the preliminary design of solid-fueled ramjet missiles. An elementary code determines the baseline system configuration comprised of warhead, guidance-control, and propulsion masses and geometries from specific correlations found in the literature. Then, the system is refined with the help of external and internal ballistics codes. Equations of motion are solved for the flight's ascending, cruising, and descending stages and the internal ballistic set of equations designs the ramjet engine based on liquefying fuels. The combined tools sized the booster and the ramjet sustainer engines for a long-range missile, intended to transport 200 kg of payload for more than 300 km range flying near 14,000 m altitude at Mach 3.0. The refined system configuration had 600 mm in diameter and 8,500 mm in length with overall mass of 2,128 kg and 890 kg/m3 density. Ramjet engine propellant mass fraction was estimated as 74%. Increased missile range can be attained with paraffin-polyethylene blend burning at near constant regression rate through primary air mass flow rate control and lateral 2-D air intakes.

• 한국소음진동공학회논문집
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• 제18권4호
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• pp.458-464
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• 2008

The structural health monitoring has been gaining more importance in civil engineering areas such as earthquake and wind engineering. The use of health monitoring system can also provide tools for the validation of structural analytical model. However, only few structures such as historical buildings and some important long bridges have been instrumented with structural monitoring system due to high cost of installation, long and complicated installation of system wires. In this paper, the structural monitoring system based on cheap and wireless monitoring system is investigated. The use of advanced technology of micro-electro-mechanical system(MEMS) and wireless communication can reduce system cost and simplify the installation. Further the application of wireless MEMS system can provide enhanced system functionality and due to low noise densities. Identification results are compared to ones using data measured from traditional accelerometers and results indicate that the system identification using wireless MEMS system estimates system parameters accurately.

• 한국기계가공학회지
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• 제7권4호
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• pp.82-95
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• 2008

As society has changed to being more knowledge-based, it is necessary that change of paradigm is incorporated into engineering education and the education goals and the assessment method of educational outcomes is developed to promptly meet the needs of the times. A purpose of this study is to measure learning outcomes in coursework of engineering college every semester, which ultimately provides to validate program outcomes. We looked into teaching-learning style of course in the engineering college and analyzed its grade method and tool. By use of a survey, we derived a reasonable method to measure for the learning outcomes in course and presented tools for course-embedded assessment to measure that learning outcomes had been tied to their objectives. These tools are effective to determine that program outcomes and education goals have been achieved, ultimately. In addition, it will help that instruction builds a loop system for better.

• Journal of Computational Design and Engineering
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• 제1권1호
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• pp.67-77
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• 2014

Most engineering software tools use typical menu-based user interfaces, and they may not be suitable for learning tools because the solution processes are hidden and students can only see the results. An educational tool for simple beam analyses is developed using a pen-based user interface with a computer so students can write and sketch by hand. The geometry of beam sections is sketched, and a shape matching technique is used to recognize the sketch. Various beam loads are added by sketching gestures or writing singularity functions. Students sketch the distributions of the loadings by sketching the graphs, and they are automatically checked and the system provides aids in grading the graphs. Students receive interactive graphical feedback for better learning experiences while they are working on solving the problems.

• International Journal of Naval Architecture and Ocean Engineering
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• 제11권1호
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• pp.1-10
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• 2019

Nowadays, the study on Floating Offshore Wind Turbines (FOWTs) is being performed globally. Dozens of numerical simulation tools have been developed for designing FOWTs and simulating their performances in combined wave and wind environments. On the other hand, model tests are still required to verify the results obtained from numerical simulation tools. To predict seakeeping performance of the OC3-Hywind platform, a OC3 spar model moored by a 3-leg catenary spread mooring system with a delta connection was built with a 1/128 scale ratio. The model tests were carried out for various sea states, including rotating rotor effect with wind in the Ocean Engineering Wide Tank, University Of Ulsan (UOU). The model test results are compared with the numerical simulations by UOU in-house code and FAST.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 추계학술대회 논문집
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• pp.564-567
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• 2004

In the manufacture of integrated circuits, photolithography is the lowest yield step in present production lines. Electron beams form a powerful set of tools with which to attack this problem. Electron beams can be used to make patterns that are smaller than can a photolithography. We design a high voltage generator of electron beam manufacturing system. For this purpose, first, the configuration of electron beam manufacturing system was analyzed. Second, the basic configuration of a high voltage generator and test results were presented.

• 산업경영시스템학회지
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• 제23권59호
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• pp.85-95
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• 2000

Since the cost of a new product is determined mainly at the design stage, systematic tools to support the new product to be manufactured at the predetermined cost is very important for successful introduction of a new product. PDM is a tool to support engineers to integrate product data throughout the product development. In this paper, we introduce a prototype of PDM system which has a target costing function, where cost estimation is coupled with structured product data.

• KIEE International Transactions on Power Engineering
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• 제2A권4호
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• pp.145-152
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• 2002

This paper illustrates applications of the Component Object Model (COM) for power system software developments. As an integral part of Microsoft's component services, COM has gained increased popularity for developing enterprise applications. This paper illustrates the concepts of COM and the latest developments as well as the available tools for developing COM components. Possible COM applications for developing power system software, such as sparse matrix manipulation, fault location, genetic algorithm applications, and so on. are presented. Advantages and promises brought about by COM are manifested through these examples.

• 산업경영시스템학회지
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• 제18권36호
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• pp.315-322
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• 1995

Quality audit is one of tools to evaluate the effectiveness and compliance of quality system. Quality system will be improved through quality audit. This paper describes the considerations such as audit team, audit process, audit checklist and auditor's communication skills to perform effective quality audit. The result of quality audit depends on the auditees attitudes. Thus, the auditor's manner is very important to gain a good audit result.

• 한국CDE학회논문집
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• 제13권6호
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• pp.412-420
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• 2008

In order to design the large complex structures like VLFS (Very Large Floating Structures), it is essential the cooperation between the experts in various fields; structural engineering expert, fluid mechanics expert, mooring system engineer, and so on. This paper describes the development of an integrated system to support the cooperative design between various experts and project manager. This integrated system is designed to be operated in Web environment and it contains the support of design DB and 3D graphical tool, negotiation tool for task allocation, and various engineering supporting tools for each design step. The user group of this system can be classified as Project Manager, Engineering Expert, DB Builder, and System Administrator. All of the engineering data is saved after and during the process of the design projects and all participants can be connected by Internet without the limit of time or space constraints.