• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.1A
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• pp.51-58
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• 2008

A cable element happens to vibration easily rather than other elements because a cable element has few rotational stiffness. Dynamic motion of stay cable is distinguished from vibration by wind and/or rain and excitation by support movement. Mostly a stay cable is vibrated by wind and/or rain except that when natural periods coincide between stiffening girder and stay cable. It happens to deterioration of serviceability and durability by vortex shedding, rainy-wind induced vibration, and galloping. Additional damping generated by installation of cable damper is well known good scheme against above phenomena. Researchers have lack of effort to develop the recommendations even if cable stayed bridges are designed and constructed in Korea. Therefore, development of the domestic recommendations should be achieved as soon as possible. This study suggests the consistent and systematic recommendations on vibration controlling design of stay cable by installation of damper. It gives readers two important methodologies that one evaluates required damping ratio, the other determines installing point considering efficiency.

• Journal of the Korean Society for Library and Information Science
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• v.58 no.1
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• pp.123-149
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• 2024

The purpose of this study is to present a plan to simplify the issuance of public library loan membership cards for children under the age of 14, and to devise measures to promote the convenience of using public libraries and to promote their use. To this end, related laws and systems, related services, and systems were analyzed. The issuance cases for each type were derived and analyzed by thoroughly investigating the procedure for issuing loan membership cards for children under the age of 14 in 1,211 public libraries nationwide, and focus group interviews were conducted. Based on this, the "double diamond model" was employed among service design methodologies to propose step-by-step guidelines for simplifying the procedure for issuing public library loan membership cards for children under the age of 14, as well as improving the environment, such as the roles of stakeholders, laws, and systems.

• Korean Journal of Construction Engineering and Management
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• v.15 no.1
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• pp.122-133
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• 2014

Recent diversification of project delivery systems coupled with increasing mega-projects requires highly advanced construction management techniques. Among those techniques, procurement and design management are recognized as being the first priority for overseas construction projects. Nevertheless, previous research in design management has been limited to the quality management of the design documents at design stage. Therefore, it is necessary to explore the design management from a comprehensive perspective throughout the project life cycle. In this context, the purpose of this paper is to propose a conceptual framework for integrated design management (IDM). Several different concepts in relation to design management were investigated first in order to identify the major variables of the IDM framework. A comprehensive comparison of construction management methodologies was also analyzed in order to identify key factors of IDM. Finally, an IDM framework was proposed by combining those factors and relevant issues. Based on the proposed framework, a survey was conducted in order to validate the framework as well as to identity important areas for improving competitive capability of Korean construction companies.

• The Journal of the Korea Contents Association
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• v.19 no.11
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• pp.111-121
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• 2019

Recently, through the services that use drones at fire sites to deliver on-site and road conditions into the situation room and life-saving activities or the deliveries of first aid outfits at the accident scenes that are inaccessible to humans, there are more and more cases of dealing with emergency situations. Therefore, by studying the service design using drones in the initial stage of response to fires in dense residential areas, this study was intended to reify the service design area of the response stage, including the dispatch of fire sites and the fire suppression. To do this, through literature researches, research directions were explored by examining the concept and process review of service design, and by analyzing the application cases using service design. In order examine the validity of this study, a one-on-one interview was conducted to identify the use and problems of drones among incumbent firefighters, and identified the applicability of drones to fire sites by targeting drone experts. Field research was conducted to identify the location and distance of road conditions, site conditions, and 119 safety centers, by making Yongsan-gu, the most vulnerable area to fire in Seoul, as a research sample. And, among the methodologies of service design, Persona and Customer Journey Map were prepared and Insight was derived, by using virtual scenarios for the experience values and behavior analyses of the interested parties. Through these processes, this researcher intended to present the fire-response service design and help establish the direction of service design in the initial stages of fire in Korea.

• Journal of the Korean Society of Marine Environment & Safety
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• v.21 no.5
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• pp.558-570
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• 2015

A study on the green ship design for Ultra Large Container Ship (ULCS, 18,000 TEU Class Container Ship) was performed based on the four step procedures of the initial design and hull form optimization to maximize economic and propulsive performance. The first, the design procedure for ULCS was surveyed with economic evaluation considering environmental rules and regulations. The second, the characteristics of single and twin skeg container ships were investigated in view of initial design and performances. The third, the hull form optimization for single and twin skeg ships with the same dimensions was conducted to improve the resistance and propulsive performances at design draught and speed by several variations and the results of the optimization were verified by numerical calculations of CFD and model test. The last, for the estimated operating profile of draught and speed, the hull forms of single and twin sked ships were optimized by CFD. From this study, the methodologies to optimize the hull form of ULCS were proposed with considerations during the green ship design and the improvement of the energy efficiency for the optimized hull forms was confirmed by the proposed formula of the total energy considering design conditions, operating profile and fuel oil consumption.

• Applied Chemistry for Engineering
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• v.31 no.4
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• pp.377-382
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• 2020

A sequential design of experiments was employed to optimize MOF-235 synthesis for acetylene adsorption process. Two experimental designs were applied: a two-level factorial design for screening and a central composite design, one of response surface methodologies (RSM). In this study, 2³ factorial design of experiment was used to evaluate the effect of parameters of synthesis temperature and time, and also mixing speed on crystallinity of MOF-235. Experiments were conducted 16 times follwing MINITAB 19 design software for MOF-235 synthesis. Half-normal, pareto, residual, main and interaction effects were drawn based on the XRD results. The analysis of variance (ANOVA) of test results depicts that the synthesis temperature and time have significant effects on the crystallinity of MOF-235 (response variable). After screening, a central composite design was performed to optimize the acetylene adsorption capacity of MOF-235 based on synthesis conditions. From nine runs designed by MINITAB 19, the result was calculated using the second order model equation. It was estimated that the maximum adsorption capacity (18.7 mmol/g) was observed for MOF-235 synthesized at optimum conditions of 86.3 ℃ and 28.7 h.

• Archives of design research
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• v.12 no.2
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• pp.171-182
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• 1999

This study aims to clarify the nature and properties of multimedia interface design, and to identify direction of multimedia interface design research. It also focuses on forecasting boundaries and major trends in current researches on multimedia interface design. The two jargons, 'interface' and 'interaction', are distinguished clearly to show the definition and boundary of multimedia interface. The multidisciplinary nature of multimedia interface design is identified as a result of examination and analysis on major researches. Nine research cases have been selected and categorized into two directions as the theoretical approach and the technical approach. Major characteristics of each case are examined in terms of subjects and methodologies. Findings on current states of the multimedia interface design research are: $\circled1$increasing importance of contextuality; $\circled2$emerging tendency for perceiving the content as one of interacting subjects; $\circled3$providing idiomatic interface context; and $\circled4$paying much attention to the meaning of minor actions. Those findings can be possible as a result of expansion of boundary of multimedia content with rapid distribution of multimedia in recent years. The study concludes that further researches can be activated on the basis of the concept of content-based multimedia interface.

• The Journal of the Korea Contents Association
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• v.19 no.8
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• pp.205-213
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• 2019

A number of small and medium design companies in Korea are making efforts to develop distinguished products with an aim to survive and prosper. However, it is quite difficult to succeed due to insufficient experience in product planning and the challenges in applying known methodologies, which are based on a large amount of data presented as best practices in designing process, in the actual small and medium enterprise operations. To this end, this study suggested the usefulness of the user participation process as the methodology for small and medium design companies and chose the user FGD method implemented by Company P which is a small design company as an empirical case study. The following are the processes used in the case study; First, the problems of existing baby bath were derived through user FGD. Second, opinions were collected from various classes of users through in-depth interviews. Third, the ideas derived were analyzed with the KJ method and grouped based on similar elements, through which six design directions and detailed design concepts covering size, material, safety, purchase factors of existing product, direction of improvement, additional elements were derived. Through the case study, this study verified that the FGD method of Company P could improve the practical verification, integration and promptness of the product planning process in small and medium enterprises. This is valuable as a realistic process that small and medium enterprises with limited capital and manpower may adopt.

• Transactions on Control, Automation and Systems Engineering
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• v.4 no.1
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• pp.9-16
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• 2002

In this paper, we intend to demonstrate a new intuitive force-feedback device for advanced VR applications. Force feed-back for the device is tension based and is characterized by 7 degrees of freedom (DOF); 3 DOF for translation, 3 DOF for rotation, and 1 DOF for grasp). The SPIDAR-G (Space Interface Device for Artificial Reality with Grip) will allow users to interact with virtual objects naturally by manipulating two hemispherical grips located in the center of the device frame. We will show how to connect the strings between each vertex of grip and each extremity of the frame in order to achieve force feedback. In addition, methodologies will be discussed for calculating translation, orientation and grasp using the length of 8 strings connected to the motors and encoders on the frame. The SPIDAR-G exhibits smooth force feedback, minimized inertia, no backlash, scalability and safety. Such features are attributed to strategic string arrangement and control that results in stable haptic rendering. The design and control of the SPIDAR-G will be described in detail and the Space Graphic User Interface system based on the proposed SPIDAR-G system will be demonstrated. Experimental results validate the feasibility of the proposed device and reveal its application to virtual reality.

• Journal of the Korean Institute of Telematics and Electronics C
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• v.36C no.8
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• pp.22-34
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• 1999

In this paper, an efficient test algorithm for embedded dual-port memories is presented. The proposed test algorithm can be used to test embedded dual-port memories faster than the conventional multi-port test algorithms and can be used to completely detect stuck-at faults, transition faults and coupling faults which are major target faults in embedded memories. Also, in this work, BIST which performs the proposed memory testing algorithm is designed using Verilog-HDL, and simulation and synthesis for BIST are performed using Cadence Verilog-XL and Synopsys Design-Analyzer. It has been shown that the proposed test algorithm has high efficiency through experiments on various size of embedded memories.