• International Journal of Naval Architecture and Ocean Engineering
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• v.12 no.1
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• pp.48-59
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• 2020

A traditional propeller can easily become entangled with floating objects while operating. In this paper, we present a newly developed Electromagnetic-valve-control-based Water-jet Propulsion System (ECWPS) for an unmanned surface cleaning vessel that can be flexibly controlled via a Micro Control Unit (MCU). The double-structure was adapted to the unmanned surface cleaning vessel for floating-collection missions. Computational Fluid Dynamics (CFD) software for operating effect simulation was also used to reveal the working principle of the ECWPS under different conditions. Neglecting the assembly technique, the design level, controlling strategy, and maneuvering performance of the ECWPS reached unprecedented levels. The ECWPS mainly consists of an Electromagnetic-valve Array (EA), pipeline network, control system, and water-jet source. Both CFD analyses and experimental results show that the hydraulic characteristic of the ECWPS was predicted reasonably, which has enormous practical value and development prospects.

• Advances in nano research
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• v.14 no.2
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• pp.141-154
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• 2023

Effects of viscoelastic foundation on vibration of curved-beam structure with clamped and simply-supported boundary conditions is investigated in this study. In doing so, a micro-scale laminate composite beam with two piezoelectric face layer with a carbon nanotube reinforces composite core is considered. The whole beam structure is laid on a viscoelastic substrate which normally occurred in actual conditions. Due to small scale of the structure non-classical elasticity theory provided more accurate results. Therefore, nonlocal strain gradient theory is employed here to capture both nano-scale effects on carbon nanotubes and microscale effects because of overall scale of the structure. Equivalent homogenous properties of the composite core is obtained using Halpin-Tsai equation. The equations of motion is derived considering energy terms of the beam and variational principle in minimizing total energy. The boundary condition is assumed to be clamped at one end and simply supported at the other end. Due to nonlinear terms in the equations of motion, semi-analytical method of general differential quadrature method is engaged to solve the equations. In addition, due to complexity in developing and solving equations of motion of arches, an artificial neural network is design and implemented to capture effects of different parameters on the inplane vibration of sandwich arches. At the end, effects of several parameters including nonlocal and gradient parameters, geometrical aspect ratios and substrate constants of the structure on the natural frequency and amplitude is derived. It is observed that increasing nonlocal and gradient parameters have contradictory effects of the amplitude and frequency of vibration of the laminate beam.

• Archives of design research
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• v.13 no.4
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• pp.125-135
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• 2000

As computers have became popular and multimedia and internet are frequently used, the volume and exchange of information have explosively increased. Therefore, more organized information system is needed for a more efficient use of information. For this reason, the importance of information design and interface design is highly recognized. This thesis is to present the user-oriented interface design prototype based on the environmental analysis of the user and information design. For this purpose, the theoretical study of information design and the principle and elements of GUI (Graphic User Interface) design is preceded. Information design is to subdivide and organize information according to its characteristic, and to systemize information structure considering the interrelationship of information. GUI design, that is interface design based on graphics, should be made in consideration of GUI elements and principle for the user's easy access of information. As it is said, much information needs to be structurized systematically and also visualized as the interface design esthetically as well as functionally. In conclusion, this study presents the effectual user-oriented interface design prototype by researching many theories of information design and GUI design and applying such theories to GUI design.

• Journal of Practical Engineering Education
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• v.14 no.2
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• pp.235-244
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• 2022

In this study, a class operation case of an engineering design project targeting a golf ball dispenser, a commercial product, was presented. The project was carried out according to the systematic engineering design approach suggested by Kim Jong-won and W. Beitz. This method broadly divides engineering design into four stages: 'product planning → conceptual design → basic design → detailed design'. In particular, the conceptual design stage is divided into 'functional structure diagram → detailed working principle exploration → various design alternatives creation → optimal design selection'. In the conceptual design, the input/output of the golf ball dispenser was defined and a functional structure diagram was prepared for it. Through this process, it was possible to subdivide the functions of the product and to easily explore the working principle for each. The searched working principles are devised as various design alternatives by various combinations, and for each proposal, the advantages and disadvantages were compared with each other to derive the optimal design alternative. In the basic design, the prototype layout was completed through failure mode analysis and the actual prototype was manufactured using it. Through the entire process, students participating in the class will be able to design commercial products in a systematic way and experience manufacturing prototypes within the department of mechanical engineering curriculum.

• Journal of Korea Trade
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• v.24 no.7
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• pp.73-92
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• 2020

Purpose - The letter of credit has been playing a major role to diminish overall risks which exist among concerned parties even though there are differences such as language, culture, law, and distance. This paper reviews essence of the letter of credit and its transaction principles, as well as overall practical questions based on the L/C transaction principle. It also investigates the risk of fraud occurrences in L/C transactions and the importance of fraud prevention and preventive measures in international L/C transactions, including the Fraud Rule, which is a major topic to consider in business transactions. Design/methodology - It is considered that an importing country's concerned parties and an exporting country's concerned parties face different situations. This study employs the existing framework to identify liability, responsibility, and obligation for all concerned parties across countries. Using a quite direct measurement of principles in the letter of credit, such as principle of independence, principle of abstraction, and principle of strictness and coincidence, we studied these differences. Findings - Our main findings can be summarized as follow. The paper enhances the efficiency of the L/C payment method to provide fraud generated from L/C transactions, presentation of a theoretical framework about fraud and fraud prevention, which international trading companies should acknowledge in a material way based on fraud risk resulting from taking advantage of L/C transaction principles. Originality/value - Existing studies focus on fraud accidents in L/C transactions by taking bad advantage of the characteristics of the letter of credit without suggesting risks of fraud. This paper attempts to evaluate and provide preventive measures as a solution for fraud and risky international business in a letter of credit transaction. This area of trade studies is underexplored, both empirically and theoretically, although the issue has long been important to Korean and world community foreign trade.

• International Journal of Internet, Broadcasting and Communication
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• v.15 no.2
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• pp.157-167
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• 2023

As a new trend in the development of urban public spaces, the use of right-angle LED screens perfectly combines building facades with naked-eye 3D visual effects, providing designers with a brand-new creative platform. How to create a realistic naked-eye 3D effect on a right-angle LED screen and bring an immersive visual experience to the audience has become a question worth exploring. So far, production companies have yet to announce the relevant design ideas and complete production methods. In order to explore the production principle and production process of the naked-eye 3D effect of the right-angle LED screen, we summarize the basic production principle of the naked-eye 3D impact of the right-angle LED screen through case analysis. Based on understanding the production principle, the actual case production test was carried out, and a complete production process of the naked eye 3D visual effect of the right-angle led screen was tried to be provided by off-line rendering. For the problem of how to deal with image deformation, we provide two production methods: post-production software correction and UV mapping. Among them, the UV mapping method is more efficient and convenient. Referring to this paper can help designers quickly understand the production principle of the naked eye 3D effect of right-angle LED screens. The production process proposed in this paper can provide a reference for production method for related project producers.

• Journal of the Korean housing association
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• v.15 no.4
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• pp.9-16
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• 2004

Architectural theories in western architecture have been considered as a basis for answering the fundamental questions of architectonics: proportion, symmetry, color, harmony and so on. Among those the architectural design theory is significant, since it affects the aesthetic evaluation of human perception. This paper gives an outline in applying the traditional design principles of architecture to contemporary architecture by 'unification through similarity' of architectural components such as form, scale, texture and color. As we see from this research, unification can be achieved in a design by the combination of the four components; that is, to balance between the four above-mentioned components in buildings, through the similarity of one or more of these components.

• Journal of Navigation and Port Research
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• v.27 no.6
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• pp.599-604
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• 2003

In this paper, the ergonomic principle and concept will be established and the conceptual bridge design based on the ergonomic studies pertaining to bridge design undertaken by IMO and ISO will be introduced. In particular, this study has looked into the applicability of ergonomic design concept on coastal ships and proposes new bridge design to make good contribution to the prevention of marine accidents in the coastal sea.

• Journal of the Korean Institute of Rural Architecture
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• v.9 no.1
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• pp.1-8
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• 2007

This study is on landscape design of existing rural village focused on for improvement of community. It's so one of serious problems in landscape in almost rural area of the nation. For the finding clue of landscape design of village view through this study, we surveyed 1 village located in Sangju city. By surveying landscape design factor of village, we can propose design method and a few results as follow; Firstly, the structure of village landscape has five principle factors. The five factors of landscape are history and culture, housing and building, nature, agriculture, and environment design. Secondly, color existing of housings is to contain a primary color on roof which is not in harmony. Nevertheless, we can also find the reform measure and the possibility because of the knowledge of village people.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.05a
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• pp.314-315
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• 2018

The long-life housing certification system must have been applied more than 1,000 households apartments since 2015. The basic design guideline for the popularization of long-life housing has been developed in 2017, which include the concept of long-life housing and basic principle of design long-life housing. The demonstration project of long-life housing is be currently under construction in Sejong-si. The aim of this study is to find items on design checklist considering construction stage. The main goal is the development of design manual of long-life housing.