• The Journal of Korean Academy of Prosthodontics
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• v.54 no.3
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• pp.193-202
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• 2016

Purpose: This study was performed in order to assess the effect of the surface treatment methods and the use of bonding agent on the shear bond strength (SBS) between the aged CAD-CAM (computer aided design-computer aided manufacturing) hybrid materials and added composite resin. Materials and methods: LAVA Ultimate (LU) and VITA ENAMIC (VE) specimens were age treated by submerging in a $37^{\circ}C$ water bath filled with artificial saliva (Xerova solution) for 30 days. The surface was ground with #220 SiC paper then the specimens were divided into 9 groups according to the combination of the surface treatment (no treatment, grinding, air abrasion with aluminum oxide, HF acid) and bonding agents (no bonding, Adper Single Bond 2, Single Bond Universal). Each group had 10 specimens. Specimens were repaired (added) using composite resin (Filtek Z250), then all the specimens were stored for 7 days in room temperature distilled water. SBS was measured and the fractured surfaces were observed with a scanning electron microscope (SEM). One-way ANOVA and Scheffe test were used for statistical analysis (${\alpha}=.05$). Results: Mostly groups with bonding agent treatment showed higher SBS than groups without bonding agent. Among the groups without bonding agent the groups with aluminum oxide treatment showed higher SBS. However there was no significant difference between groups except two subgroups within LU group, which revealed a significant increase of SBS when Single Bond Universal was used on the ground LU specimen. Conclusion: The use of bonding agent when repairing an aged LAVA Ultimate restoration is recommended.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.05a
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• pp.107-109
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• 2012

It is a very important to manage inventory quickly and accurately in Refrigerated commercial warehouses in which a lot of logistics are often shipping and receiving. Because most of systems for managing refrigerated warehouses consist of COBOL, it will be raised maintenance costs. There is no service for consignees who are consumer of refrigerated warehouses and they use only a fax or a phone for orders. In this paper, we design a mobile framework based on smart phones and supporting a variety of value-added services which are fit consignees, solving problem of outdated legacy systems and no services for consignees. We also implement the mobile framework which is consists of the JSP server and the android clients.

• KIPS Transactions on Computer and Communication Systems
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• v.9 no.2
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• pp.31-36
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• 2020

The creation of the Defense Integrated Data Center(DIDC) has resulted in a reduction in manpower, operating costs, efficient and effective management of resources. However, it is difficult to effectively collect and manage the data of a large number of battlefields coming from equipments such as drones, robots, and IoT added to the fourth industrial revolution and the future battlefield. Therefore, we will propose the design of DIDC network system using NFV and SDN, which are emerging as the core technologies of 5G, a mobile communication technology. After analyzing the data sheet of each equipment, it is considered that by integrating the redundant functions, energy efficiency, resource utilization and effective network management will be possible.

• Journal of The Korean Association of Information Education
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• v.21 no.3
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• pp.335-342
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• 2017

The artificial intelligence, robot technology, Internet of things, and life sciences that create added value while dramatically transforming human life have been highlighted in the fourth industrial revolution, the next industrial revolution. In order to adapt to the 4th industry, it is necessary to educate students to develop fusion thinking and computing thinking ability. Therefore, in this study, we developed a digital Yut Playing system based on physical computing, reflecting STEAM and decomposition, pattern recognition, abstraction, and algorithm design, which are components of computing thinking. By experiencing the developed system and applying it to education, it raised interest and interest in programming education and improved programming lesson for fusion thinking and computing thinking ability.

• Transactions of the Korean Society of Mechanical Engineers
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• v.13 no.3
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• pp.490-499
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• 1989

These days the closed cycle gas turbine attracts considerable attention due to : (1) The possibility of directly coupling the closed cycle gas turbine with a high temperature gas cooled reactor ; (2) the economical use of dry coolers to reduce the thermal charge of the environment ; and (3) the reduction of pollution and energy consumption, by replacing the domestic hearth by a central heating and power station. In this paper, we selected the optimal cycle from the characteristic of thermodynamic cycle for the optimal design of closed CO$_{2}$ gas turbine cycle usuable in nuclear energy power plant. Also the effects of between the parameters and thermal efficiency were investigated by computer simulation. These results and design data will be added to basics in optimal designing closed CO$_{2}$ cycle gas turbine plant.

• International Journal of Precision Engineering and Manufacturing
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• v.7 no.2
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• pp.8-11
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• 2006

Gas-assisted injection molding (GAIM) process reduces the required injection pressure during mold filling stage as well as the shrinkage and warpage of the part and cycle time. Despite of these advantages, this process needs new parameters and makes the application more difficult because gas and melt interact during the injection molding process. Important GAIM factors involved in this process are gas penetration design, locations of gas injection points, shot size, delay time to inject gas as well as common injection molding parameters. In this study, the experiments are conducted to investigate effects of GAIM process variables on the gas penetration for PP (Polypropylene) and ABS (Acrylonitrile Butadiene Styrene) moldings by changing the gas injection point. Taguchi method is used for the design of the experiments. When the gas is injected at a cavity's center, the most effective factor is the shot size. When the gas is injected at a cavity's end, the most effective factor is the melt temperature. The injection speed is also an effective factor in GAIM process.

• Fashion & Textile Research Journal
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• v.24 no.1
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• pp.15-28
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• 2022

In the Fourth Industrial Revolution era, with its accelerating radical changes and innovation, fashion is rapidly advancing to sustain social changes introduced by technological convergence. In light of this, the study investigates the social and cultural characteristics of technologizing fashion products: creative modifications emerge from technological convergence with fashion products and result in a realm separate from technology. By focusing on the nature of fashion, this study analyzes the technologization of fashion products for added value creation in the fashion system. Based on the findings, it interprets different attitudes toward technologizing that changes fashion products. Accordingly, this study reviews previous literature and qualitatively examines empirical cases based on inductive reasoning. In particular, it analyzes commercialized cases of fashion-technology convergence in fashion products found on online fashion media outlets between January 2007 and May 2021, a central period in intellectual and technological innovation. The characteristics of technologized fashion products are identified as follows: expansion of physical functions and categories, interaction with emotional sensibilities, artistry through combination with technologies, and computer-generated imagery(CGI) fashion as digital goods. Therefore, this study analyzes the characteristics of technologization, focusing on the social and cultural properties of fashion products. The findings provide opportunities to understand the paradigm shift of these products that was catalyzed by technologizing.

• Bulletin of the Society of Naval Architects of Korea
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• v.17 no.1
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• pp.25-29
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• 1980

For the preliminary estimation of the vertical hull natural frequency, the Schlick's or Schlick-type formulae have been traditional ones and are still in common use today. Some investigators have made their efforts, based on statistical data of ships' system parameters, to extend the applicability of Schlick-type formulae to higher modes, or to utilize the Rayleigh method. For instance, the work done by Dinsenbacher et al.[5] belongs to the former and that of Nagamoto et al.[6] to the latter. In a part of his previous paper[7], the author, investigating the case of a cargo ship of medium size, suggested that provided statistically simplified curves such as trapezoid of system parameter distributions are available in hands, direct utlization of an ordinary computer program can be also an another convenient method by which we can obtain both natural frequencies and normal mode shapes. In this paper, to confirm the feasibility of the above suggestion, four high speed boats are investigated. The system parameters of them are originally given in [5]. The computer program used here is one confiled based on a calculation method derived from Myklestal-Prohl modeling of hull, transfer matrix formulation and an extended Gumbel's initial value method for solving frequency equation. The results of the investigation show that the direct calculation based on statistically oriented and reasonably assumed trapezoidal mean curves of system parameter distributions can give us natural frequencies within about 5% deviation up to several-noded modes and normal mode shapes serviceable at least up to 4- or 5-noded modes in comparision with those based on actual distributions of system parameters. For this simplified method the actual data required for input are only of ship length, displacement, total added mass, bending and shear rigidity at amidship. They are available at the early stage of design. By this method we can also easily trace variations of vibration characteristics in the course of ship design cycles.

• Journal of the Korea Society of Computer and Information
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• v.13 no.2
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• pp.211-220
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• 2008

The home network technology which used USN is developing quickly. Use yet line to a lot of part as home network technology. Recently be leap into prominence to technology core of home network as wireless technology a ZigBee. ZigBee Perceive with cognition from tag and sensor as use USN, and processing, save, integration, and provide information. Implement the access control system which used technology BigBee with design at these papers. The wireless-based construction that used ZigBee. The influence that can let you implement early a Ubiquitous society is technology there being. Also, show by a large spinoff in an allied industry field, and improve the quality of life, and invention calls value added of leading edge IT service and product. The implementation of mobile base on access control system using zigbee method is expected to be helpful for the convenience in home network use.

• Journal of Korea Society of Digital Industry and Information Management
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• v.6 no.3
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• pp.159-168
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• 2010

Developments and changes in digital environment based on computer technologies and internet networks enabled us interactive communication for planning and execution through the freedom of 'connection', 'sharing', and 'conversion'. The subject of this study, interactive commercial, might be the core of success based on creation which stems from communication design, revolution in design and technology, and conversion. Communication in modern economy is not optional, but essential. Furthermore, like evolution process up to Augmented Reality from developments of mobile communication technology, or concept in paradigm change, digital interactive commercial means the core of success, not a part of it. Therefore, in order to achieve success in the global competition structure, mobile communication design, revolution, and creation which produce added value shall be working as a base. In order to reach effective communication process performance of interactive commercial media, this study would like to propose building a media commercial system which is realized by human senses. Using this, standardized methods for interactive commercial which can be used together with augmented reality based on digital technology, and for using digital robot contents are available, along with methodology system of their use. In addition, the ultimate goal of this study aims to discover new factors through reorganization of precedent analysis and adaptation based on academic achievement and practical application. And thus, it wants to contribute to practical use of interactive commercial out of augmented reality-based communication in which technology, marketing, and design are integrated to be used in real sense.