• International conference on construction engineering and project management
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• 2005.10a
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• pp.881-885
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• 2005

Scheduling repetitive projects under limitations on the amounts of available resources (labor and equipment) has been an active subject because of its practical relevance. Traditionally, the limitation is specified as a deterministic (fixed) number, such as 1000 labor-hours. The limitation, however, is often exposed to uncertainty and variability, especially when the project is lengthy. This paper presents a stochastic optimization model to treat the situations where the limitations of resources are expressed as probability functions in lieu of deterministic numbers. The proposed model transfers each deterministic resource constraint into a corresponding stochastic one and then solves the problem by the use of a chance-constrained programming technique. The solution is validated by comparison with simulation results to show that it can satisfy the resource constraints with a probability beyond the desired confidence level.

• Journal of the Korean Society of Industry Convergence
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• v.25 no.6_2
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• pp.969-977
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• 2022

Currently, in Korea, aerial photogrammetry is being studied for cadastral boundaries and numerical maps. Since the announced value of cadastral survey is closely related to ownership, the accuracy and reliability of the published value should be emphasized above all else. However, although aerial photogrammetry has great advantages in economic feasibility and surveying efficiency, it has many limitations when extracting the boundary of cadastral survey based on the acquired image. In order to improve these limitations, in this study, an aerial target was applied to obtain reliability improvement. Therefore, in order to examine the usefulness of aerial photogrammetry for cadastral survey application, cadastral boundary extraction and accuracy comparison analysis were conducted.

• Proceedings of the KIPE Conference
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• 2005.07a
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• pp.690-692
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• 2005

Among many other alternative energy resources, small scale hydropower has been brought into attention as a reliable source of energy today, which had been relatively neglected since 1960s. Present low head of Francis turbines and small scale hydro turbines, however, have limitations in the minimum required head and flow rate for efficient operation. This study attempts to develope the Francis turbine which is expected to run efficiently even in very low head and small flow rate, so that the limitations on the conventional small scale hydropower could be alleviated and competition with other alternative energy sources in the changable design conditions could be attained. The Francis turbine of a new concept was designed based on changable design conditions, hydrodynamics and theory of power transmission.

• The Journal of Korea Robotics Society
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• v.7 no.2
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• pp.129-141
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• 2012

The purpose of this study was to analyze Early Childhood Teachers' awareness of R-Learning. The Subjects were 6 Early Childhood Teachers who experienced to use Robot in their teaching and learning. The data was analyzed through semi-structured in-depth interview and teachers' journals. The results showed possibilities and limitations of R-learning. As possibilities of R-learning, it was found that robot is am attractive teaching materials. In addition, it was found that robot might be an assistant teacher. Third, robot helps children improving their social development. Fourth, teachers might get confident while using robots in their teaching and learning. However, there were limitations of R-learning. First, teachers need to understand what R-learning means. Second, there are some functional problems of R-learning. Third, there are lack of qualitative contents of R-learning. Finally, robots need to be general to every children.

• Korean Management Science Review
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• v.28 no.1
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• pp.53-60
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• 2011

Time series analysis methods have been traditionally used in stock price prediction. However, most of the existing methods represent some methodological limitations in reflecting influence from external factors that affect the fluctuation of stock prices, such as oil prices, exchange rates, money interest rates, and the stock price indexes of other countries. To overcome the limitations, we propose a network based method incorporating the relations between the individual company stock prices and the external factors by using a graph-based semi-supervised learning algorithm. For verifying the significance of the proposed method, it was applied to the prediction problems of company stock prices listed in the KOSPI from January 2007 to August 2008.

• Journal of the Korean Operations Research and Management Science Society
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• v.1 no.1
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• pp.89-94
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• 1976

Many techniques have been applied to comprehensive regional planning through the processes of goal-building, research and analysis, plan-establishing, implementation-scheduling, and evaluation. Operations research(OR) is one of those techniques. OR has been developed in such fields of military operations, industrial engineering and business management during the last three decades in several developed western countries. It is a recent tendency for public administrators and researchers to be interested in OR for their scientific decision making. Therefore, we see that OR has not only a weak basis on, but a few practical applications to urban and regional planning. Such situation is worse in developing countries. This paper aims at investigating the possible basis and limitations or obstacles of OR application to public decision making, especially regional planning. A practical example of OR application to regional planning in Korea and its evaluation will be introduced.

• Journal of the Society of Naval Architects of Korea
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• v.56 no.5
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• pp.396-409
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• 2019

In this paper, a comparative study on the radiation techniques for the motion analysis of the three dimensional floating structure with the forward speed was carried out. The Sommerfeld radiation condition, the damping technique, and the point shift technique were used for the comparative study. Radiated wave patterns and hydrodynamic coefficients of the heave motion of floating structure with the forward speed were compared and analyzed. The characteristics and limitations of each radiation technique were analyzed through the calculation results. To overcome the limitations of conventional radiation techniques, the hybrid radiation technique combining the Sommerfeld radiation condition with the damping technique was proposed. It is confirmed that the proposed method, the Hybrid radiation technique, improves the limitation of the speed range and the dissipation of the wave of the conventional radiation technique. The motion analysis code of the three dimensional floating structure with the forward speed based on the Rankine source method with hybrid radiation technique was developed. In order to validate the developed code, hydrodynamic analyses were carried and compared with published experiments.

• International Journal of Computer Science & Network Security
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• v.22 no.9
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• pp.343-347
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• 2022

To date, the use of artificial intelligence has already brought certain results in such areas of art as poetry, painting, and music. The development of AI and its application in the creative process opens up new perspectives, expanding the capabilities of authors and attracting a new audience. The purpose of the article is to analyze the essential, artistic, and technological limitations of AI art. The article discusses the methods of attracting AI to artistic practices, carried out a comparative analysis of the methods of using AI in visual art and in the process of writing music, identified typical features in the creative interaction of the author of a work of art with AI. The basic principles of working with AI have been determined based on the analysis of ways of using AI in visual art and music. The importance of neurobiology mechanisms in the course of working with AI has been determined. The authors conclude that art remains an area in which AI still cannot replace humans, but AI contributes to the further formation of methods for modifying and rethinking the data obtained into innovative art projects.

• Korea Trade Review
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• v.44 no.5
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• pp.161-174
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• 2019

Recent studies on trade payment methods have suggested various alternatives to replace remittance payments. However, these studies theoretically provided the possibilities and limitations of each alternative. To check recent changes in trade practices, our research analyzed payment methods in international trade e-marketplace. Using company and product information obtained from Alibaba.com, we analyzed payment methods used in this e-marketplace and examined determination factors for new payment methods. According to the results of logistic regression analysis, we found a relationship between new payment method and factors such as market competition and the age of the company. Also, providing Paypal payments showed a correlation with market competition and price level of products as well as e-commerce infrastructure. Though these study results feature limitations in the generalization of results, it contributes to the research on payment method trends in international trade.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.26 no.6
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• pp.38-46
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• 2012

In this paper, the necessity for the identification of the absolute phase value is introduced and analyzed for a particular conductor line of a 3-phase type distribution network and the recent methods are also introduced. For the determination of the exact phase value for a specific point in the line, as compared with the phase reference point, the measured phase value must be within a range of ${\pm}60[^{\circ}]$. However, the phase of a particular point can fluctuate depending on the line constant, transformer wiring method, line length, line amperage, etc. A theoretical formulation such as Simulink modeling and analysis for a distribution network are conducted for the identification of phase at a specific point in the line. In particular, through evaluating the effects of unbalanced current loads at the time of determination of the phase value, the limitations of the present method for the determination of phases is described.