• Ocean Systems Engineering
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• v.11 no.1
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• pp.83-97
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• 2021

The submerged U-shape breakwater interaction with the solitary wave is simulated by the Boussinesq equations using the finite-difference scheme. The wave reflection, transmission, and dissipation (RTD) coefficients are used to investigate the U-shape breakwater's performance for different crest width, Lc1, and indent breakwater height, du. The results show that the submerged breakwater performance for a set of U-shape breakwater with the same cross-section area is related to the length of submerged breakwater crest, Lc1, and the distance between the crests, Lc2 (or the height of du). The breakwater has the maximum performance when the crest length is larger, and at the same time, the distance between them increases. Changing the Lc1 and du of the U-shape breakwaters result in a significant change in the RTD coefficients. Comparison of the U-shape breakwater, having the best performance, with the averaged RTD values shows that the transmission coefficients, Kt, has a better performance of up to 4% in comparison to other breakwaters. Also, the reflection coefficients KR and the diffusion coefficients, Kd shows a better performance of about 30% and 55% on average, respectively. However, the model governing equations are non-dissipative. The non-energy conserving of the transmission and reflection coefficients due to wave and breakwater interaction results in dissipation type contribution. The U-shape breakwater with the best performance is compared with the rectangular breakwater with the same cross-section area to investigate the economic advantages of the U-shape breakwater. The transmission coefficients, Kt, of the U-shape breakwater shows a better performance of 5% higher than the rectangular one. The reflection coefficient, KR, is 60% lower for U-shape in comparison to rectangular one; however, the diffusion coefficients, Kd, of U-shape breakwater is 35% higher than the rectangular breakwater. Therefore, we could say that the U-shape breakwater has a better performance than the rectangular one.

• The Journal of the Korea Contents Association
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• v.10 no.6
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• pp.115-133
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• 2010

For assessment of U-Eco City technologies, more concrete definition of those technologies are required. However, almost researches defined technologies as conceptually and even cannot include all of them. In this sense, the purpose of this study is to deduct assessing items for specifying applying priority of U-Eco City technologies. We performed the research by 3 steps. Firstly, we deduct assessing items of the technologies by researching their advance process. After then, we compensate the defect of those items through documentary research and made a periodic table about core technologies that can be useful for deducting long-term items. The assessing items what are deducted as a result of this study can be applied to the selection of technology, and will be useful to construct more objective and systematized U-Eco City. Furthermore, if assessment frame about technologies and services is developed from this research, it gives to us probability that standardized process of U-Eco City construction can be established.

• Journal of Korean Society for Geospatial Information Science
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• v.22 no.3
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• pp.87-97
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• 2014

City is currently developing into intelligent city which adopts the ICT technology to resolve the problems and increase the competitiveness. This intelligent city is promoted under the name of U-City or Smart City, yet it is also criticized in the trend for what the differences between U-City and Smart City are. In this study, we draws the differences between U-City and Smart City from our distinctive research method, text mining which analyzes the trend of research papers, and contribute to direction of U-City study in the future. Through this analysis, the study results in that U-City focuses practical implementation in domestic cities while Smart City focuses technological development and provision of single service. However, this paper has a limitation as the subjective opinion was reflected to configure the sets of keywords, and only keywords and s were analyzed. Therefore, further studies are needed to confirm the differences between U-City and Smart City with related research papers and reports.

• Journal of the Korea Safety Management & Science
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• v.6 no.1
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• pp.173-185
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• 2004

The production using U-shaped line is studied. This research presents the relationship among machining time, cycle time and production rate in a U-shaped line. The U-shaped line produces shafts by automated machines. In this paper when any production rate is given the U-shaped line always satisfies the production rate. An algorithm is developed for the determination of cycle time, the number of machines and workers of the U-shaped line in order to minimize the total machine capacity and the number of workers for any given production rate. The U-shaped line was successfully designed by applying the proposed algorithm.

• Korea Journal of Hospital Management
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• v.15 no.4
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• pp.27-42
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• 2010

The purpose of this study is to investigate the intention to utilize u-healthcare services in Korea. Specifically, this study attempted to identify the relationships among the intention to use u-healthcare, consumer's demographic characteristics, and personal information technology level. We conducted telephone interview and collected data from 406 householders 20 years old or older. The results showed significant differences in use intention of u-healthcare service by innovation, gender, and their interaction term. Residence area and average time of internet use had significant effect on the use intention of u-healthcare service. Also, the interaction term between innovation and education level had a significant effect on use intention. Based on the results we concluded that the consumer's characteristics and information technology level had a significant effect on the use intention of u-healthcare service.

• Management & Information Systems Review
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• v.21
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• pp.155-168
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• 2007

In the ubiquitous which is rapidly developing with ultra speed thes days, constructing the u-Campus which is using the sensor-network as its base is keep developing. Also, any information related equipments like PC and mobile, computing is possible whenever and wherever you want and due to the development of the wireless network, the service environment is continually developing. In this article, I'd like to suggest the u-Campus which is very suitable to the user's environment which had used application of mobile. In u-Campus, various techniques are adopted and applied along with development of info-communication related technidques. Especially, the new type of campus which is constructed by adopting the ubiquitous computing net-work technique to the campus of university is the u-Campus. In this article, by suggesting u-Yuhan designing methods, more effective and advanced school activities of students to make possible.

• Proceedings of the Korea Society for Industrial Systems Conference
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• 2003.11a
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• pp.227-237
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• 2003

U-learning stresses the ubiquitous networking environment where different sizes of U-devices, let alone the dominant PCs, comprise a background infrastructure to enhance knowledge and performance. This paper suggests a U-learning system that will provide an alternative for the hectic private lessons, particularly English training among grade-school students. Several points are suggested of the U-system to be a cost-effective alternative. Besides the corresponding advancement of U-networking, the production of a profitable business model harnessing the emerging technology is most urgent. The Government authorities should recognize the potential U-social system solutions, and take an initiative to develop them. The latest technology seems to throw a light to the upcoming social systems applied in various fields of social needs.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.1377-1382
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• 2009

U-City related researches and development have been actively conducted in Korea since 2002. According to the Act on Ubiquitous City Construction, "U-City" is defined as "the city to provide ubiquitous service anytime anywhere through the existing ubiquitous backbone systems and ubiquitous technologies, ultimately for the purpose of improving urban competitiveness and quality of life. This research explains the plan to develop collective management technology for integrated operation of U-Space which makes up U-City. Specifically, this report is intended to suggest basic approach of identifying collective management elements of each U-Space type, developing integrated management system and creating interface module to link the system with urban integrated operation center.

• Bulletin of the Korean Mathematical Society
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• v.22 no.1
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• pp.17-22
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• 1985

B.M. Munshi and D.S. Bassan defined and developed the concept of super continuity in [5]. The concept has been investigated further by I. L. Reilly and M. K. Vamanamurthy in [6] where super continuity is characterized in terms of the semi-regularization topology. Super continuity is related to the concepts of .delta.-continuity and strong .theta.-continuity developed by T. Noiri in [7]. The purpose of this note is to derive relationships between super continuity and other strong continuity conditions and to develop additional properties of super continuous functions. Super continuity implies continuity, but the converse implication is false [5]. Super continuity is strictly between strong .theta.-continuity and .delta.-continuity and strictly between complete continuity and .delta.-continuity. The symbols X and Y will denote topological spaces with no separation axioms assumed unless explicity stated. The closure and interior of a subset U of a space X will be denoted by Cl(U) and Int(U) respectively and U is said to be regular open (resp. regular closed) if U=Int[Cl(U) (resp. U=Cl(Int(U)]. If necessary, a subscript will be added to denote the space in which the closure or interior is taken.

• The Journal of Fisheries Business Administration
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• v.17 no.1
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• pp.107-115
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• 1986

The United States is the world's leading importer of frozen processed groundfish products, with over two thirds of total world imports. Over 90% of the U.S. groundfish demand is met by inports, while about 2 million mt of groundfish are taken from U, S. waters by joint-venture and foreign fleets. The objective of this paper is to provide descriptive information concerning the U.S. groundfish market and the potential for groundfish resources off Alaska to become a major source of supply to this market. The size of the U.S. market, U.S. imports, trade policies, and catch from U.S, waters are discussed, and a comparison is made between the potential domestic catch of groundfish off Alaska and current U.S. groundfish consumption. The total optimum yield of 2.3 million mt for flounders, cod, and pollock is about four times the round weight equivalent of U.S. imports of these species in 1984.