• Journal of Internet Computing and Services
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• v.3 no.1
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• pp.81-90
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• 2002

Large-scale distributed applications based on Internet and client/server applications have to deal with series of problems. Load balancing, unpredictable communication delays, and networking failures can be the example of the series of problems. Therefore. sophisticated applications such as teleconferencing, video-on-demand, and concurrent software engineering require an abstracted group communication, CORBA does not address these paradigms adequately. It mainly deals with point-to-point communication and does not support the development of reliable applications that include predictable behavior in distributed systems. In this paper, we present our design, implementation and performance analysis of the group communication using the CORBA-ORB. JAVA-RML and Socket based on distributed computing Performance analysis will be estimated latency-lime according to object increment, in case of group communication using ORB of CORBA the average is 14.5172msec, in case of group communication using RMI of Java the average is 21.4085msec, in case of group communication using socket the average is becoming 18.0714msec. Each group communication using multicast and UDP can be estimated 0.2735msec and 0.2157msec. The performance of the CORBA-ORB group communication is increased because of the increased object by the result of this research. This study can be applied to the fault-tolerant client/server system, group-ware. text retrieval system, and financial information systems.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.5
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• pp.1838-1844
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• 2010

In distance education, contents are to convey what to learn to learners, and the efficient quality assurance of contents is the very first step to the enhancement of distance education. Most studies of the quality assurance of contents have mostly centered around the development of evaluation tools, and few studies have ever focused on analysis of the quality of contents itself, since it's not easy to do that due to difficulties in the selection of evaluatees or of contents to be analyzed. The purpose of this study was to analyze the quality of 58 distance education contents of on-the-job training and another training for the acquisition of qualifications. As a result, the contents of the learning contents segment ranked first. Among the components of each segment, there was room for improvement in the level of learning and learning elements in the learning contents segment. In terms of instructional design, the quality of interaction components should be taken to another level to boost the quality of contents in this segment. The findings of the study are expected to give some suggestions about which parts of contents should be improved in quality from a perspective of contents developers or suppliers to enhance the overall quality of contents.

• Journal of Broadcast Engineering
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• v.12 no.3
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• pp.230-241
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• 2007

This paper presents the requirements analysis for the Terrestrial DMB Automatic Emergency Alert Service (AEAS) Standard. First, the basic concepts in disaster management and the AEAS system structure are presented as a background. Next, other emergency alert systems and the related standards are analyzed. We propose taxonomy to categorize the emergency alert systems and analyze the characteristics of each system. Next, we analyze advantages of T-DMB for the delivery medium of emergency alert message and problems to resolve for the enhanced performance. Finally, we propose service requirements which will achieve general/special-purpose, non-interrupting, location-adaptive, automatic, message delivery service. The paper will contribute as a guideline to the development for emergency alert service standards for other broadcasting media.

• Journal of Internet Computing and Services
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• v.20 no.6
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• pp.85-93
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• 2019

Computational Science and Engineering is a convergence study that understands and solves complex problems such as science, engineering, and social phenomena through modeling using computing resources. Computational science and engineering combines algorithms, computational and informatics, and infrastructure. The importance of computational science is increasing with the improvement of computer performance and the development of large data processing technology. In Korea, Korea Institute of Science and Technology Information (KISTI) has been developing national computational science engineering software and utilization technology by combining basic science and computing technology through EDISON project. The EDISON project builds an open EDISON platform and integrates and services information systems in seven areas of computational science and engineering (computational thermal fluids, nanophysics, computational chemistry, structural dynamics, computational design, and computational medicine). Using this, we have established a web-based curriculum to lay the groundwork for fostering scientific talent and commercializing computational science and engineering software. The purpose of this study is to derive the quality characteristic factors of computational science platform and to empirically examine the effect on user satisfaction. This paper examines how the quality characteristics of information systems, the computational science engineering platform, affect the user satisfaction by modifying the research questions according to the propensity of the computational science platform by referring to the success factors of DeLone and McLean's information system. Based on the results of this study, we will suggest strategic implications for platform improvement by searching the priority of quality characteristics of computational science platform.

• Journal of the Korea institute for structural maintenance and inspection
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• v.14 no.6
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• pp.153-161
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• 2010

Numerous past studies have shown that safety and serviceability of many concrete infrastructures and buildings built in 1970's have far less strength capacities than their original intended design capacities, thereby requiring repair and strengthening. Currently, aged concrete structures are being repaired using various methods developed in the past. Unfortunately, these methods do not consider the specific conditions that these members are under, but they merely attach repairing materials on the external surface for random strength improvements. Therefore, in order to improve repair and strengthening methods by considering composite behavior between repairing material and structural member, enhanced construction methodologies are needed. Also, the enhanced repairing and strengthening methods must be able to be implemented on structural members constructed using high performance concrete to meet the present construction demand of building mammoth structures. Therefore, in this study, a repairing and strengthening method for retrofitting high strength concrete (HSC) columns that can effectively improve column performance is developed. A square HSC column's cross-sectional shape is converted to an octagonal shape by attaching precast members on the surface of the column. Then, the octagonal column surface is surface wrapped using Carbon Fiber Sheets (CFS). The method allows maximum usage of confinement effect from externally jacketing CFS to improve strength and ductility of repaired HSC columns. The research results are discussed in detail.

• Journal of Radiation Protection and Research
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• v.38 no.1
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• pp.22-28
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• 2013

The skyshine effect is an essential and important phenomenon in the shielding design of the high energy accelerator. In this study, a new estimation method of neutron skyshine was proposed and was verified by comparison with existing methods. The effective dose of secondary neutrons and photons at the locations that was far away from high-energy electron accelerator was calculated using FLUKA and PHITS Monte Carlo code. The transport paths of secondary radiations to reach a long distance were classified as skyshine, direct, groundshine and multiple-shine. The contribution of each classified component to the total effective dose was evaluated. The neutrons produced from the thick copper target irradiated by 10 GeV electron beam was applied as a source term of this transport. In order to evaluate a groundshine effect, the composition of soil on the PAL-XFEL site was considered. At a relatively short distance less than 50 m from the accelerator tunnel, the direct and groundshine components mostly contributed to the total effective dose. The skyshine component was important at a long distance. The evaluated dose of neutron skyshine agreed better with the results using Rindi's formula, which was based on the experimental results at high energy electron accelerator. That also agreed with the estimated dose using the simple evaluation code, SHINE3, within about 20%. The total effective dose, including all components, was 10 times larger than the estimated doses using other methods for this comparison. The influence of multiple-shine path in this evaluation of the estimation method was investigated to be bigger than one of pure skyshine path.

• Culinary science and hospitality research
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• v.22 no.5
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• pp.64-81
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• 2016

The study, based on existing studies, explored influencing relationship, suggesting app service quality and user reviews as previous elements to affect use satisfaction about users' comments based on big data and reuse intention. The study includes a comparative analysis of existing studies. Based on such analysis results, the authors looked into app service quality elements perceived by gourmet restaurant app users and the role of user reviews, and suggested practical implications that can help the development and operation of gourmet restaurant app contents. The study subjects were male and female consumers who over 20 years old throughout Korea who had not a searched smartphone gourmet restaurant app in the three months preceding the survey. The subjects were selected from consumers who search the restaurantsby using restaurant apps like Mango plate, Dining code, Hot place, and selecting restaurants. Among them, consumers with experience using restaurants were finally selected for the survey. According to the results, reliability, informativity, and system capability, among service quality, had positive influences on app use satisfaction, while design and mobility had no effect. App use satisfaction had positive influences on app reuse intention. User comment informativity played a controlling role. The study explored the importance of app service quality and user review informativity as elements that affect continued use of gourmet restaurant apps by dining-out consumers.

• The Journal of Natural Sciences
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• v.8 no.2
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• pp.289-321
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• 1996

After the two big wars (Imjin Woeran and Byungia Horan), the Lee Dynasty confronted rapid transitional periods in almost all aspects of the society. Corruption of the governmental system by the wars and disordered social structures also caused confusion in the social position system. In addition, development of the commercial economic system and monetary economy brought up a new rich middle-class, "Joong in Gyegeup". In ideological aspects, Confucianism indulged in and stick to isms and ics, and the Confucian morality slackened, thus a more pragmatic ideology, "Silhak Sasang", developed. And the emergence of the modern literature and art of the 'common people' was followed by the appearance of the common-people class including those having the common-people concept among the noble-class "Yangban Gyegeup". This evoked a new common costume culture and the fashion appeared. The public could no longer find the power and appeal from the preexisting ruling classes due to the changed role and sense of value. Thus, they sought a new symbolic leader group that would to be the new standard of the newly changed society. That was a group of people called as "Kisaeng" liberal and independent. They were performing social activities, enjoying poetry, music and dancing, and classy dressers, having physically attractive bodies. The erotic as well as luxurious mode proposed by them reflected the trend of that time. It concurred well with the concept and taste of the public, so it was accepted with a good response. That is, by following these leaders, the public achieved their identification and tried to share the prestige of the leaders. For this reason, the Kisaeng group attracted the public attention and led the taste of the public, thereby becoming the influential fashion leaders of that age.

• Korean Journal of Optics and Photonics
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• v.22 no.1
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• pp.46-52
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• 2011

A confocal microscope was developed utilizing a scanning sample stage based on a home-built double-compound flexure guide. A scanning sample stage with nano-scale resolution consisted of a double leaf spring based flexure, a displacement amplifying lever, a Piezo-electric Transducer(PZT) actuator and capacitance sensors. The performance of the two-axis stage was analyzed using a commercial finite element method program prior to the implementation. A single line laser was employed as the light source along with the Photo Multiplier Tube(PMT) that served as the detector. The performance of the developed confocal microscope was evaluated with a mouse ear skin imaging test. The designed scanning stage enabled us to build the confocal microscope without the two optical scanning mirror modules that are essential in the conventional laser scanning confocal microscope. The elimination of the scanning mirror modules makes the optical design of the confocal microscope simpler and more compact than the conventional system.

• Food Science and Preservation
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• v.21 no.5
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• pp.661-667
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• 2014

The quality characteristics of cookies with 0%, 2%, 4%, 6%, and 8% acaiberry (Euterpe oleracea Mart.) powder added were analyzed through chemical and sensory evaluations. The moisture contents of the cookies were insignificant (p<0.05) as the acaiberry powder levels (0%, 2%, 4%, 6%, and 8%) increased. The pH values of the cookies were significantly reduced in all the acaiberry powder groups compared to the controls. According to the Hunter color of the cookies, tbe L-value (lightness) and the b-value (yellowness) significantly decreased (p<0.05), whereas the a-value (redness) increased when the acaiberry powder was added at different levels (0%, 2%, 4%, 6%, and 8%). The spread factor decreased significantly (p<0.05) with the acaiberry powder addition levels (0%, 2%, 4%, 6%, and 8%). The hardness of the cookies significantly decreased (p<0.05) according to the increase in the acaiberry powder level (0%, 2%, 4%, 6%, and 8%). The sensory evaluation of the cookies showed that those with 6% acaiberry powder added had the greatest of the color, taste, flavor, texture, and overall acceptability. These results showed that up to 6% acaiberry powder can be added to cookies.