• Journal of Astronomy and Space Sciences
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• v.36 no.2
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• pp.69-74
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• 2019

Spacecraft requires sufficient power in orbit to perform its mission. So as to comply with system requirements, the sufficient power should be made by a solar cell array by photovoltaic power conversion. A life time of space program depends on its mission considering parts reliability and parts grade. Based on the mission life time, power equipment might be designed to meet specifications. In outer space, solar cell array might generate the dc power by photovoltaic conversion effects and GaInP/GaAs/Ge solar cells are used in this study. Space programs that require more than five years should select parts for high reliability applications. Therefore, reliability analysis for high reliability applications should be performed to check its fulfilment of the requirements. This program should also require more five years for its mission and we performed its analysis using parts count method (PCM) for its reliability. Finally, we performed reliability analysis and obtained quantitative figures found out 99.9%. In this study, we presented the reliability analysis of the 300 W GaInP/GaAs/Ge solar cell array.

• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.2
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• pp.314-323
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• 2022

Vessel Traffic Services (VTS) operators perform traffic management tasks using VTS systems and sensor equipment designated as VTS facilities to promote the safety and efficiency of vessel traffic. The necessary VTS information for effective operations could be obtained through the additional access of various information channels other than the designated VTS facility. To unify these various information access windows, the development of the VTS cloud system is in progress. In this study, the operational information analysis for VTS was performed through VTS tasks-facility linkage analysis to identify the user required information according to the introduction of the VTS cloud system. The VTS task analysis was performed through research of the international and domestic literature, and expert interviews. The necessary information were identified and linked according to the VTS facilities. As a result of the analysis, 37 categories of necessary information were identified for internal and external information windows, and 8 information windows were selected other than the present VTS equipment. The identified user requirements would be applied to the structure design of the VTS cloud system. In the future, it is necessary to update user requirements through scenario-based user operation analysis and to conduct additional research on the system interface design.

• Journal of Cadastre & Land InformatiX
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• v.44 no.1
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• pp.195-212
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• 2014

This study was performed in order to contributing the influence factors in the real estate marketing strategy which largely affects the success of a real estate sale and development projects. Articles have to be concluded with the Influence factors of Satisfaction based on the type of Real Estate through PLS Regression Analysis. Building data was conducted by the target population specializing in the real estate sale and development business. Classification of real estate business classified by the way of the residential and non-residential parted. In the case of Housing type in the analysis result, the main factors were made by calculating the each factor such as brand trust, Strengthening the alliance and partnership, Traffic environment, Relaxing the requirements for a Real estate sales, Business presentation, Unsold benefits and Relaxing the requirements for payment. Otherwise, In the case of non-residential in the analysis result, the factors such as Relaxing the requirements for payment, Customer Orientation, living environment, Unsold benefits, Strengthening the alliance and partnership and communication terms made an influence to satisfaction.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.46 no.10
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• pp.845-855
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• 2018

Cross section design of a prop-blade is carried out for VTOL(Vertical Takeoff and Landing) Quad Tilt Prop-rotor UAV with a maximum takeoff weight of 55 kg and a maximum cruising speed of 180 km/h. Design procedure for cross section design is established and design requirements for prop-blade are identified. Through the procedure, cross section design is carried out to meet the identified requirements. Main design factors including stiffness, weight per unit length, and elastic axis are obtained by using a finite element section analysis program, and the design weight of the prop-blade is predicted. The obtained design factors are used along with the rotor system analysis program CAMRAD II to evaluate the dynamic stability of prop-blade in operating environment. In addition, the prop-blade load is obtained by CAMRAD II software, and it is used to verify the safety of the prop-blade structure. If the design results are not satisfactory, design changes are made in an iterative manner until the results satisfy the design requirements.

• Journal of Biomedical Engineering Research
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• v.44 no.1
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• pp.1-10
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• 2023

With the announcement of MEDICAL DEVICE REGULATION 2017/745 (MDR) on April 5 2017, medical device manufacturers shall apply ISO 14971:2019 (3^rd) revised in December 2019. However, there is not much related information and guidance available to medical device manufacturers, especially single use medical device. Risk management process basically follow 5 steps which are Risk Analysis, Risk Evaluation, Risk Control, Evaluation of overall residual risk and post-production activities. The purpose of this study is to provide a guidance of from risk analysis with Failure Mode and Effects Analysis (FMEA) table to overall residual risk evaluation for the single use medical device and to reflect it in a Periodic Safety Update Reports (PSUR) to satisfy with MDR requirements with single use medical device which are widely used and manufactured FDA class 2 or CE class IIb as examples. For this study, single use medical device manufacturer can adopt ISO 14971:2019 in accordance with MDR requirements and it can be extended to the PSUR. But there are still limitations to adopt to the all-single use medical device especially high class, private device and implantable device. So, Competent Authority (CA) shall publish more guidance for the single use medical device.

• Journal of Advanced Marine Engineering and Technology
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• v.40 no.9
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• pp.812-817
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• 2016

This paper dealt with electrical and optical requirements of naval vessel's LED luminaires. And the products have been tested to determine whether the products meet these requirements or not. This study analyzes the cost-effectiveness of the LED luminaires which have been implemented for the application to naval vessel since 2012. The LED requirements were proposed based on comparison among other standards/specifications such as Korean Industrial Standard(KS), Korean Defense Specification(KDS) and US Navy Military Specification(MIL). Application of the proposed requirements were then be verified by analyzing and testing the electrical and optical characteristics of both fluorescent Luminaires and LED luminaires, and the LED luminaires were installed to A1 naval vessels according to the proposed requirements. As results, approximately 40% of power consumption was saved by using LED luminaires compared to using fluorescent luminaires while luminous flux was increased by 10~15%. Moreover, using LED luminaires of the proposed requirements exhibited the effect of reducing approximately 4,900 fluorescent luminaires in 10 naval vessels in the time period between 2012 to 2015, which is equivalent to cost reduction of \0.56M approximately. Such cost reduction is further expected considering the LED luminaires will continue to be applied to naval vessels in the future.

• Structural Engineering and Mechanics
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• v.43 no.4
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• pp.545-560
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• 2012

Design codes provide the minimum requirements for the design of code-compliant structures to ensure the safety of the life and property. As for code-exceeding buildings, the requirements for design are not sufficient and the approval of such structures is vague. In mainland China in recent years, a large number of code-exceeding tall buildings, whether their heights exceed the limit for the respective structure type or the extent of irregularity is violated, have been constructed. Performance-based seismic design (PBSD) approach has been highly recommended and become necessary to demonstrate the performance of code-exceeding tall buildings at least equivalent to code intent of safety. This paper proposes the general methodologies of performance-based seismic analysis and design of code-exceeding tall buildings in Mainland China. The PBSD approach proposed here includes selection of performance objectives, determination of design philosophy, establishment of design criteria for structural components and systems consistent with the desirable and transparent performance objectives, and seismic performance analysis and evaluation through extensive numerical analysis or further experimental study if necessary. The seismic analysis and design of 101-story Shanghai World Financial Center Tower is introduced as a typical engineering example where the PBSD approach is followed. The example demonstrates that the PBSD approach is an appropriate way to control efficiently the seismic damage on the structure and ensure the predictable and safe performance.

• Journal of Korea Technology Innovation Society
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• v.20 no.1
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• pp.81-102
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• 2017

Financing, manpower support and tax are the most popular tools for policy for small and medium enterprises (SMEs). This paper, however, will introduce information analysis support for SMEs and will prove that can be a good tool. The information analysis support means the support of technology and market information for the technology development or commercialization of SMEs. Therefore, the support is a customized one. In the theory domain, we adopt and prove two theoretical grounds as an SMEs policy such as market and system failure. In the policy tool domain, we suggest four requirements to be an SMEs policy and prove the tool to satisfy these requirements. All the data and proofs are from a government research institute called K.

• The KIPS Transactions:PartD
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• v.16D no.6
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• pp.871-880
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• 2009

Along with the complexity and size growth of embedded software, it is critical to meet the nonfunctional requirements such as power consumption as well as functional requirements such as correctness. This paper, apart from the existing studies of source code-based power analysis, proposes an approach of model-based power analysis using UML 2.0. Specially, we focus on the development of energy library to analyze the power consumption of embedded software. Our energy library supports model-based power analysis, and also supports the easy adaption for the change of embedded application.

• Proceedings of the KSR Conference
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• 2003.05a
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• pp.694-699
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• 2003

Rotem Company has designed and manufactured a railway vehicle body according to the European standard EN 12663, which applies to all railway vehicles within the EU(European Union) and EFTA(European Free Trade Association) territories. EN 12663 specifies the loads vehicle bodies shall be capable of withstanding, identifies how material data shall be used and presents the principles to be used for design verification by analysis and test. The structural design of railway vehicle bodies depends on the loads they are subjected to and the characteristics of the materials they are manufactured from. However, the structural requirements of EN 12663 are very different from those of existing Korean and Japanese regulations and standards. Therefore, in order to fulfill the structural requirements, Rotem Company has carried out Finite Element Analysis (FEA) and has performed load tests on the vehicle body according to EN 12663. This research contains the results obtained by the analysis and the load tests. The analysis is carried out using I-DEAS Master Series 8 and specially designed test jigs and equipment are used for the load tests.