• Journal of the Korea Concrete Institute
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• v.22 no.4
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• pp.595-603
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• 2010

Monte-Carlo simulation technique is often used in order to predict service life of concrete structure subjected to chloride penetration in marine environment based on probability theory. Monte-Carlo simulation method, however, the method gives different results every time that the simulation is run. On the other hand, moment method, which is frequently used in reliability analysis, needs negligible computational cost compared with simulation technique and gives a constant result for the same problem. Thus, in this study, moment method was applied to the calculation of corrosion-initiation probability. For this purpose, computer programs to calculate failure probabilities are developed using first-order second moment (FOSM) and second-order second moment (SOSM) methods, respectively. From the analysis examples with the developed programs, SOSM was found to give a more accurate result than FOSM does. The sensitivity analysis has shown that the factor affecting the corrosion-initiation probability the most was the cover depth, and the corrosion-initiation probability was influenced more by its coefficient of variation than its mean value.

• Journal of the Korean Data and Information Science Society
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• v.28 no.5
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• pp.1001-1019
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• 2017

The signal processing is a field of the electrical engineering but it is very much related with the time series analysis. Thesedays the commercial softwares are widely used by the reseachers. We have attempted to make a guide for using the R-package in the digital signal processing. It would be good to read the materials in each section first and to follow the plots in the section 8 and to run the attached R-codes. The article consists of (1) Fourier transform and Fourier inverse transform, (2) spectral analysis (3) parametric and non-parametric estimation for the period (4) filter design. Simple theoretical explanations are provided and R implementations are added.

• Journal of Distribution Science
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• v.4 no.1
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• pp.161-173
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• 2006

The most important two decision-makings which a retail store owner face require which place of the store should geographically be established and which stock should be properly placed on the shelves. The problem of geographic positioning is the decision-making for the store's positioning and stock arrangement within the retail store is the decision-making for the placement store. In order to determine the positioning, the expected area should be analyzed so that the analysis of commercial area can usually be implemented in accordance with retail marketing strategy and therefore the sized of the potential market for example each distric's clientele, competition and, a municipal community's regulations, could be evaluated. But I contend that with only the size of potential market does not give an adequate answer to the problem of a store's positioning. Through the estimation of commercial are in combination with feng-shui, the theory of divination based on topography, the store's position could be selected, taking a positive energy, Gi. This thesis is the starting point of these trials. In the long run, the actual analysis of the study should be continued in a more scientific, systematic, statistical way.

• The Journal of Information Technology
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• v.5 no.3
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• pp.19-34
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• 2002

The aim of this paper was to study the theoretical background of the convention industry firstly, in which will serve to seek for more efficient plan of promotion. As a result of it, it is found that the convention industry has the characteristics similar to service industry rather than manufacturing, as well as complicated, interdependent ones which are closely related to every field of industries. This paper also considers the advertising, human marketing, and public relations as measures of promoting the convention industry in order to maximize its promotion activities with the characteristics of service industry and establish the plan of promoting the industry. For the effective adoption of these measures in the convention industry, the measures is analyzed by considering the properties and degrees of some convention centers respectively after the strength and weakness of each measure shall be compared. As these measures are mostly shore-run projects, there will be necessary to keep in close touch with other complementary measures in adoption of measures of promotion.

• Journal of The Korean Association of Information Education
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• v.7 no.3
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• pp.299-308
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• 2003

Programming education in the area of ICT instruction is usually considered as contributing to the improvement of one's analytical power, logic in thinking, and procedural problem-solving capabilities. However, it is hard to get access to adequate web coursewares in suit with their intellectual level of development of Korean elementary students. Most of the existing coursewares, if any, are dealing with high level and theory-oriented contents, and accordingly are quite difficult for the elementary students to understand them. In addition, it is very difficult to practice them on the Web. Drawing upon some ideas on the theories of Web-based design and learning, this study tries to develop and materialize a fresh learning courseware for Visual Basic. The Web courseware thus developed allows students to learn the basics of visual basic programming as well as the basic grammar. It also provides students with an environment that enables students to code and run programs on the Web.

• Journal of KIISE:Computing Practices and Letters
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• v.9 no.6
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• pp.674-682
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• 2003

Ship autonomous navigation is designated as what computerizes mental faculties possessed of navigation experts, which are building navigation plans, grasping the situation, forecasting the fluctuation, and coping with the situation. An autonomous navigation system, which consists of several subsystems such as navigation system, a collision avoidance system, several data fusion systems, and a motion control system, is based on an intelligent control architecture for the sake of integrating the systems. The motion control system, which is one of the most essential system in autonomous navigation system, controls its propulsion and steering gears to move the ship satisfying its hydrodynamic characteristics. This paper is the study on the ship movement control system and its implementation which are totally developed and run on virtual-world system. Receiving the high-level control values such as a waypoint presented from the collision avoidance system, the motion control system generates them to low-level control values for propulsion and steering devices. In the paper, we develop a ship motion controller using Oldenburger's theory based on mathematical fundamentals, and simulate it with various scenarios in order to verify its performance.

• Journal of Korean Society of Disaster and Security
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• v.7 no.1
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• pp.1-8
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• 2014

This research has been studied through the actual conditional investigation about street monitoring from January to December of 2013 in Seoul city primally. As the result of this research, it has been performed aleady the Seoul city's BIS (Balanced Index Score) goal of 2013. The 18,490 cases were reported through the street monitoring activities. Despite of increasing drastically for 1,151 cases's record of 2012, Street monitoring activity appeared wide variations in the region, ages, vocation and gender. Also it depended on 25 outstanding persons of merely 3.9%. They reported 13,880 cases that run to 75.1%. On the basis of Herbert W. Heinrich's Domino theory and law of 1:29:300, the dead of 54, seriously and the slightly injured of 1,573 and the latent injured of 16,275 were decreased by eliminating unsafe state. It respected and protected the 17,903 Seoul citizen's life. This study suggested a effective improvemental method of monitoring activity by dawing a problem through Seoul and Gangdong-gu street monitor comparative analysis.

• Journal of Korea Water Resources Association
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• v.46 no.8
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• pp.795-805
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• 2013

Drought is one of the severe natural disasters and it can profoundly affect our society and ecosystem. Also, it is a very important variable for water resources planning and management. Therefore, the drought is analyzed in this study to understand the drought distribution and trend. The Standard Precipitation Index (SPI) is estimated using precipitation data obtained from 55 rain gauge stations in South Korea and the SPI based drought variables such as drought duration and drought severity were defined. Drought occurrence and joint probabilistic analysis for SPI based drought variables were performed with run theory and copula functions. And then the return period and spatial distribution of droughts on the South Korea was estimated. As the results, we have shown that Gongju and Chungju in Chungcheong-do and Wonju, Inje, Jeongseon, Taebeak in Gangwon-do have vulnerability to droughts.

• Korean journal of communication and information
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• v.45
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• pp.7-48
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• 2009

The recent crises of Marxism do not mean Marx’s crisis. Marx said that he was not a Marxist. The purposes of this essay explore (1) the modern identity of the political economy; (2) the possibilities of mutual understanding between neoclassical economics and Marxist economics; (3) problems of the political economy in media and communication industry. I have begged for analytical Marxists, because of their good fruits. They accepted the methods of modern social science and they constituted a tremendous advance in the application of the scientific methods to the study of society. In insisting on micro-foundations(methodological individualism), analytical Marxism distinguished itself from structuralism and functionalism. I appreciate that analytical Marxism has reduced a theory to practice. But the works didn’t listen to everyone(from Marxists to un-Marxists), and explain everything. Making theory with production/consumption, macro/micro, and structure/behavior is a road to the political economy in the long run. It also applies to media and communication industry. The realm of media/communication is broad, which in philosophy, humanities, politics, economics, sociology, and engineering. And media policy is more complicated by politicians who look at the same situation from different angles. By the aid of interdisciplinary research, the political economy of media/communication shall explain at full length.

• Geotechnical Engineering
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• v.8 no.1
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• pp.19-28
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• 1992

Recently, testing equipment which can run resonant column test altogether with the torsional shear test at the very highly controlled condition was developed at the University of Texas at Austin(U.S.A). With this equipment, the effects of high amplitude pre-straining vibrations on the dynamic properties of clean sands were studied. Tests showed the following results. Low amplitude shear modulus was gradually increased with little void ratio change as the number of high amplitude vibration cycles increased. Variation of volumetric strain with confining pressure for the pre -strained specimen under vibration was smaller than that of fresh specimen. Also the slope of the diagram for shear modulus and confining pressure relationship of the prestrained specimen was smaller than that of fresh specimens. These results agreed well with the analytical results.