• Transactions of the Korean Society of Mechanical Engineers B
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• v.40 no.8
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• pp.543-556
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• 2016

In this work, an insulated coupling test machine for a 5-MW-class wind turbine was designed and developed, along with the public performance testing of a 3-MW-class wind turbine. The results of the device design, development requirements, functional considerations, structural vibration analysis, and the evaluation of the insulated coupling test machine are presented in this study. For the coupling models, thick fiberglass composite pipe insulation, fabricated by filament winding, was considered. Results of three-dimensional finite element analysis conducted using both solid element and shell element modeling were analyzed and compared, considering the effect of thickness. In addition, results from the nonlinear finite element analysis of multiple leaf springs of the laminated disk pack structure were verified and compared with experimental data.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.2
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• pp.644-652
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• 2018

This paper describes the conceptual design of a customized gripper for the assembly process of IT products, which has a relatively short and regular product replacement cycle. The grippers that are used in the manufacturing field are mostly composed of one to two degrees of freedom and they can only handle one object, not multiple ones. Cost is also an important factor. If it were possible to develop a gripper suitable for the assembly process quickly and easily, some of the difficulties involved in its automation caused by the frequent changes of product and process could be solved. The assembly process utilized for this research is defined and described as the procedure and method of the process analysis due to the confidentiality of the manufacturer. We used an axiomatic design to derive the functional requirements and design parameters of the gripper used for the tablet PC assembly process. We proposed a design method for the conceptual design of the gripper by determining these parameters. For the feasibility study, a specific process was selected and the progress of the gripper design was described as an example. Although there have been studies on the design guidelines for grippers, their considerations are too general and their degree of freedom is too high. This paper defines the function of the gripper based on the assembly process of the IT products, which allows their production to be streamlined and automated. In this research, we attempted to produce a design that reflects the assembly process, not just one that enables objects to be held.

• Journal of the Korean Society for information Management
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• v.25 no.2
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• pp.183-198
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• 2008

With the purpose of enriching existing catalogues with FRBR, which is the Functional Requirements for Bibliographic Records, in mind, this paper aims to evaluate the impact of bibliographic ontology on the overall system's performance in the field of literature. In doing this, OCLC's FictionFinder(http://fictionfinder.oclc.org) was selected and qualitatively evaluated. In this study 40 university seniors evaluated the following three aspects using the 'transferring thoughts onto paper method': 1) In which ways is this FRBR-aware bibliographical ontology helpful? 2) Are the things which are initially attempted to be helped being helped? 3) Would users seeking one work in particular also see all other related works? In conclusion, this study revealed that, as Cutter claimed in his $2^{nd}$ rule of the library, collocations give added-value to the users and overall ontology provides better interface and usefulness. It also revealed that a system's evaluation with qualitative methodology helped to build full pictures of the system and to grip the information needs of the users when the system is developed. Qualitative evaluations, therefore, could be used as indicators for the evaluation of any information retrieval systems.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.1
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• pp.1-11
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• 2014

This study was carried out to investigate nutritional and physiologically active characterizations of sikhae and the seasoned products from the sea squirt Halocynthia roretzi. The total taste values of sikhae fermented for 4 and 5 days were 10.9 and 15.4, respectively, which was lower than for commercially seasoned sea squirts. The sikhaes contained mostly glutamic and aspartic acids. The total amino acid contents of sikhaes fermented for 4 and 5 days were 5.5 and 6.0 g/100 g, respectively, which were lower than those of commercial seasoned-sea squirts or similar. An amount of 100 g of sikhae and its seasoned products contained P, K, Mg and Fe, and these minerals, which are deemed good for our health, were at 10% above the recommended daily requirements. The functional properties of sikhae fermented for 4 and 5 days were as follows: for ACE inhibiting activity, 69 and 69.5%, respectively; for antioxidative activity, 28.9 and 29.3%, respectively; for xanthine oxidase inhibitory activity, 52.8 and 53.1%, respectively; and for ${\alpha}$-glucosidase inhibitory activity, 2.4 and 1.4%, respectively. Antimicrobial activity of the 5 day fermented sikhae against Vibrio parahaemolyticus and Staphyloccus aureus was detected in 8 mm and in 7 mm against Escherichia coli.

• Journal of Satellite, Information and Communications
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• v.2 no.2
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• pp.22-28
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• 2007

Spectrum spreading, in its general form, can be conceived as an artificial expansion of the signal bandwidth with respect to the minimum Nyquist band required to transmit the desired information. Spreading can be functional to several objectives, including resilience to interference and jammers and reduction of power spectral density levels. In the paper, signal spreading is manly used for increasing the received energy, thus satisfying link budget constraints, for terminals with low aperture antennas, without increasing the transmitted EIRP. As a matter of fact, in many mobile scenarios, even when MODCOD configurations with very low spectral efficiency (i.e. QPSK-1/4) in DVB-S2 standard, are used, the link budget cannot be closed. Spectrum spreading has been recently proposed as a technique to improve system performance without introducing additional MODCOD configurations under the constraint of fixed power spectrum density level at the transmitter side. To this aim, the design of spectrum spreading techniques shall keep into consideration requirements such as spectrum mask, physical layer performance, link budget, hardware reuse, robustness, complexity, and backward compliance with existing commercial equipments. The proposed implementation allows to fully reuse the standard DVB-S2 circuitry and is inserted as an 'inner layer' in the standard DVB-S2 chain.

• Journal of Astronomy and Space Sciences
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• v.20 no.4
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• pp.339-350
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• 2003

Engineering qualification model payload for a communications and broadcasting satellite(CBS) was developed by ETRI from May, 2000 to April, 2003. For. the purpose of functional test and verification of the payload, a real-time hardware-in-the-loop(HITL) CBS simulator(CBSSIM) was also developed. We assumed that the spacecraft platform for the CBSSIM is a geostationary communication satellite using momentum bias three-axis stabilization control technique based on Koreasat. The payload hardware is combined with CBSSIM via Power, Command and Telemetry System(PCTS) of Electrical Ground Support Equipment(EGSE). CBSSIM is connected with PCTS by TCP/IP and the payload is combined with PCTS by MIL-STD-1553B protocol and DC harness. This simulator runs under the PC-based simulation environment with Windows 2000 operating system. The satellite commands from the operators are transferred to the payload or bus subsystem models through the real-time process block in the simulator. Design requirements of the CBSSIM are to operate in real-time and generate telemetry. CBSSIM provides various graphic monitoring interfaces and control functions and supports both pre-launch and after-launch of a communication satellite system. In this paper, the HITL simulator system including CBSSIM, communications payload and PCTS as the medium of interface between CBSSIM and communications payload will be described in aspects of the system architecture, spacecraft models, and simulator operation environment.

• Food Science and Preservation
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• v.23 no.2
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• pp.180-187
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• 2016

The objective of this study was to investigate the quality characteristics and antioxidant activities of aronia jam prepared with different content of mashed apple. To analyze the quality characteristics pH, texture, color, antioxidant activity, total polyphenol content, and sensory property were investigated. As aronia amounts decreased, the pH of aronia jam level increased from 3.97 to 4.40, while its total acidity decreased from 0.39 to 0.27. In color, the L-, a-, and b- values increased with decreases in aronia contents when compared with 100% aroma jam. Texture evaluation revealed that the hardness, springiness, gumminess, and chewiness of 100% aronia jam were markedly higher than those of the control and other samples (p<0.05). As the aronia content decreased, both the antioxidant activity and total polyphenol content significantly decreased (p<0.05) and the total anthocyanin content gradually decreased. In the sensory evaluation, the jams containing 50% and 70% aronia showed higher values than those of other samples in overall acceptability. Taken together, aronia jam with 30% apple could be the best in order to meet the taste and functional requirements for consumers.

• The Journal of the Korea Contents Association
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• v.15 no.10
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• pp.626-635
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• 2015

Along with the social interests and needs for health, the U-Healthcare Service as a new model to control individual dietary life and to prevent chronic diseases is now drawing the public attention. In this study, the characteristics of the requirement of U-Healthcare Service were investigated from subjects aged over 50 years old. As parts of the expectation to the U-Healthcare service, the customized clinical care & control (37.7%) and the systematic understanding of individual health state (21.4%) appeared significantly. And for the application of the U-Healthcare Service to the field of healthcare, the control of dietotherapy (43.9%) appeared higher than anything else and thus the customized service for individual dietotherapy seemed to be needed. Regarding the field of searching for health information, the disease control (35.6%), food materials (28.6%), and recipe for health foods (22.7%) appeared in sequence and revealed that the majority over 50% of subjects were interested in foods. The requirements for the information of dietary formula were also investigated through 5 points scaled questionnaires on respective topics of nutritive components, menus customized for corresponding health states (diseases), and the results obtained from surveys on respective topics all showed the needs for all information by representing each point value exceeded 3.9. Through the results obtained from this study, the provision of customized information enabling the nutritional control in accordance with individual states of health or disease was estimated to be needed for the popularization of U-Healthcare Service providing contents for dietary life of clients especially those of aged over 50 years.

• Journal of Navigation and Port Research
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• v.35 no.10
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• pp.823-827
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• 2011

The present Common Structural Rules for double hull oil tanker is not included the residual strength, which is one of the functional requirements in design part of Goal-based new ship construction standards (GBS). The GBS will be enforced after July 1, 2016. The requirement related residual strength has the goal to build safe ship even if she has the specified damages due to marine accidents including collision and grounding. In order to assess the residual strength based on risk for structural damages according to GBS, tons of nonlinear FE analysis work taking into account various types of damage will be needed. The Smith's method, a kind of simplified method for the strength analysis is very useful for this purpose. In this paper, the residual strength assessments based on ultimate strength using Smith's method were carried out. The objected ship is VLCC with stranding damage in bottom structures. Also, the results were compared with that of nonlinear FE analysis using three cargo hold model.

• Spatial Information Research
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• v.23 no.4
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• pp.57-66
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• 2015

At these day, owing to functional limitations and cost issues, used image map in web service have a problem which can not make exactly meet the user needs. This study aims to create an individual map for user suitable purposes using HTML5 technology that implement the vector map creation and its functions with services. The results of this study, the invisible problems of the tilting and rotation functions in image-based map utilizing the existing web environment were solved in HTML5 vector map. And to access the map information, by implementing the function of expressing the background and name data to selectively derive, various results were expressed in the map. Also, as a result of a comparison of performance the time required was measured at 0.88sec which comes in the range of the first loading time between 0.78sec and 7.56sec in a commercial map service, which showed the possibility of its commercialization. compared to 180GB of image maps for the production of a national map index system, the volume to produce a vector map was 2.5GB, a decrease by over 90%, which solved the issue of costs for a storage space. As a result, this study of HTML5 vector map design and implementation presented a plan for providing information suitable for the requirements of the users who use spatial information through utilizing a variety of information and expanding functions.