• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 1999년도 추계학술발표대회 논문집
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• pp.49-52
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• 1999

Substituting composite structures for conventional metallic structures has many advantages because of higher specific stiffness and specific strength of composite materials. In this work, one-piece propeller shafts composed of carbon/epoxy composite and glass/epoxy one were designed and manufactured for a rear wheel drive automobile, which uses generally a steel two-piece propeller shaft. From the tests of the composite propeller shafts, it was found that the propeller shafts satisfied requirements of static torque transmission capability, torsional buckling capability and the first natural bending frequency and had 40% weight saving effect compared with steel propeller shaft.

• 한국전기전자재료학회논문지
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• 제18권1호
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• pp.68-74
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• 2005

In this work, polymerization conditions of the gel polymer electrolyte (GPE) were studied to obtain better electrochemical performances in a lithium-ion polymer battery. When the polymerization temperature and time of the GPE were 70$^{\circ}C$ and 70 min, respectively, the lithium polymer battery showed excellent a rate capability and cycleability. The TMPETA (trimethylolpropane ethoxylate triacrylate)/TEGDMA (triethylene glycol dimethacrylate)-based cells prepared under optimized polymerization conditions showed excellent rate capability and low-temperature performances: The discharge capacity of cells at 2 Crate showed 92.1 % against 0.2C rate. The cell at -20 $^{\circ}C$ also delivered 82.4 % of the discharge capacity at room temperature.

• Wind and Structures
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• 제9권5호
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• pp.369-386
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• 2006

A combination Aerodynamic/Atmospheric Boundary Layer (AABL) Wind and Gust Tunnel with a unique active gust generation capability has been developed for wind engineering and industrial aerodynamics applications. This facility is a cornerstone component of the Wind Simulation and Testing (WiST) Laboratory of the Department of Aerospace Engineering at Iowa State University (ISU). The AABL Wind and Gust tunnel is primarily a closed-circuit tunnel that can be also operated in open-return mode. It is designed to accommodate two test sections ($2.44m{\times}1.83m$ and $2.44m{\times}2.21m$) with a maximum wind speed capability of 53 m/s. The gust generator is capable of producing non-stationary gust magnitudes around 27% of the mean flow speed. This paper describes the motivation for developing this gust generator and the work related to its design and testing.

• 한국군사과학기술학회지
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• 제6권3호
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• pp.22-35
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• 2003

This paper describes system technical requirement development process from operational concept using computer-aided Systems Engineering tool(CASysE Tool-CORE). The army tactical missile system-ATACMS's technical requirements are developed by the process as a case-study The scope of the work is context analysis and requirement definition process. The proposed process is as follows. At first, an integrated architecture could be developed from the operational concept. From the integrated architecture a capability needs, which includes KPPs, are generated. And the capability needs expanded according to the Mil-Std-961D format. Lastly, a system technical requirement could be generated automatically from the CASysE Tool-CORE.

• International Journal of Safety
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• 제6권1호
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• pp.11-15
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• 2007

In many cases, rescue robots work under harsh conditions such as the presence of various obstacles, high temperature, and limited visibility, etc. These robots are required to have tough mechanical structure, good sensing and control capability, and reliable communication capability for receiving operator's command and sending information on the state of the robot and environment. In this study, a rescue robot that can investigate hazardous or disastrous sites with these capabilities is designed and implemented. The performance of the proposed rescue robot is tested under simulated disastrous environment.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.30.5-30
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• 2001

This paper describes a new design of blimp having wheeled vehicle part. This system can work both on the ground using wheeled vehicle and in the air using the floating capability of the blimp part. The passive wheeled mechanism in the vehicle part enables the stable taking off, landing on as well as it is greatly helpful to keep a stationary position on the floor. On the other hand, the floating capability enables the wheeled blimp to fly freely regardless of the ground condition or obstacles. The wheeled blimp can be used as an agent robot for the tole-presence application. Using multimedia devices such as camera, speaker, LCD and microphone mounted on the blimp surface, this system can get necessary information at the local site and communicate with person from a distance. As a typical tele-presence application, the wheeled blimp is currently being developed to a tole-guidance robot working in public indoor areas such 35 exhibition halls, departments, hospitals, etc ...

• Nuclear Engineering and Technology
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• 제50권8호
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• pp.1277-1288
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• 2018

In this work, the reactor kinetics capability is used to compute the design safety parameters in a PWR due to complete loss of coolant flow during protected and unprotected accidents. A thermal-hydraulic code coupled with a point reactor kinetic model are used for these calculations; where kinetics parameters have been developed from the neutronic SRAC code to provide inputs to RELAP5-3D code to calculate parameters related to safety and guarantee that they meet the regulatory requirements. In RELAP5-3D the reactivity feedback is computed by both separable and tabular models. The results show the importance of the reactivity feedback on calculating the power which is the key parameter that controls the clad and fuel temperatures to maintain them below their melting point and therefore prevent core melt. In addition, extending modeling capability from separable to tabular model has nonremarkable influence on calculated safety parameters.

• Structural Engineering and Mechanics
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• 제81권5호
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• pp.647-664
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• 2022

The powerful data mapping capability of computational deep learning methods has been recently explored in academic works to develop strategies for structural health monitoring through appropriate characterization of dynamic responses. In many cases, these studies concern laboratory prototypes and finite element models to validate the proposed methodologies. Therefore, the present work aims to investigate the capability of a deep learning algorithm called Sparse Autoencoder (SAE) specifically focused on detecting structural alterations in real-case studies. The idea is to characterize the dynamic responses via SAE models and, subsequently, to detect the onset of abnormal behavior through the Shewhart T control chart, calculated with SAE extracted features. The anomaly detection approach is exemplified using data from the Z24 bridge, a classical benchmark, and data from the continuous monitoring of the San Vittore bell-tower, Italy. In both cases, the influence of temperature is also evaluated. The proposed approach achieved good performance, detecting structural changes even under temperature variations.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2021년도 가을 학술논문 발표대회
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• pp.240-241
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• 2021

For the sustainable development of the domestic construction project management field, each CM company should try to diversify in terms of service contract types and scope of work while having internationally competitive technical and service capabilities as follows. First, from the initiation of the service to the completion, the CMr should be able to establish and execute a plan to create specific outcomes. Second, CMr must have the capability to produce weekly or monthly cost, schedule, risk, and scope management reports. In addition, it should be possible to apply the cost plus sliding fee method or to systematically and continuously accumulate and process data generated during the construction process.

• 문화경제연구
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• 제20권2호
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• pp.3-18
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• 2017

본 연구에서는 콘텐츠산업 인력의 업무 자율성 변화를 분석했다. 한국근로환경조사(2011, 2014) 자료에서 콘텐츠산업 인력과 업무 자율성 변수를 추출하고 이중차감추정법을 활용하여 분석한 결과 전체 표본에서는 콘텐츠산업 인력의 업무 자율성(업무 순서, 업무 방법, 업무속도)에 유의미한 변화가 나타나지 않았다. 반면 최근 콘텐츠업계의 자율성 감소는 논의는 대규모 인력과 자본이 투입되는 경우라는 것을 고려하여 30인 이상 사업체 표본을 대상으로 분석하면 콘텐츠산업 인력의 자율성이 유의미하게 감소한 것으로 나타난다. 업무의 자율성은 직위와 역량과는 정(+)의 관계가, 사업체 규모와는 부(-)의 관계가 나타난다. 본 연구는 그동안 사례 중심으로 논의되어 왔던 콘텐츠산업 인력의 업무 자율성 변화를 실증분석했다는 의의를 가진다. 또한, 인력들의 부여되는 자율성이 콘텐츠 제작 유통 과정에서 긍정적인 효과를 창출하기 위해서는 인력에 대한 보상 및 관리 체계 개선이 수반되어야 함을 제시하였다.