• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2005년도 학술발표회 논문집
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• pp.1403-1407
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• 2005

In order to analyze the water storage of the Daecheong dam after constructing the Yongdam dam situated in upstream, a daily cascaded simulation model for analyzing water storages in the Yongdam-Daecheong dams was developed. Operation scenarios of the Yongdam dam were selected to 8 cases with the combinations of downstream outflows and water supplies to the Jeonju region. Daily water storages in the Daecheong dam was analyzed daily by simulating from 1983 to 2004. The results are summarized as follows. Firstly, water supplies from the Daecheong dam were analyzed to amount $1,964.2Mm^3$ on a yearly average in case without the Yongdam dam. In case with the Yongdam dam, water supplies from the Daecheong dam were analyzed to amount $1,858.7\~1,927.3Mm^3$ in case with downstream outflow of $5\;m^3$ is, and were analyzed to amount $1,994.9\~2,017.8Mm^3$ in case with downstream outflow of $10\;m^3/s $. These values are compared to $1,649Mm^3$ applied in design. Secondly, reservoir use rate which was defined rate of water supply to effective water storage reached $241.3\% in case without the Yongdam dam. In case with the Yongdam dam, reservoir use rate reached $228.3\~236.8\% In case with downstream outflow of $5\;m^3/s$, and reached $245.1\~247.9\% in case with downstream outflow of $10\;m^3/s$. Thirdly, runoff rate which is defined rate of dam inflow to areal rainfall reached $57.3\% in case without the Yongdam dam. In case with the Yongdam dam, reservoir use rate reached $62.0\~68.4\% in case with downstream outflow of $5\;m^3/s$, and reached $64.1\~68.5\% in case with downstream outflow of $10\;m^3/s$. Fourth, in case with downstream outflow of $10\;m^3/s$ is from the Yongdam dam, appropriate water supply amounts to the Jeonju region were analyzed to only $0.50Mm^3/day$ from the daily simulation of water storages in the Yongdam dam. Comprehensively, water supply capacity of the Daecheong dam was analyzed to affect in small amounts in spite of the construction of the Yonsdam dam. It is effected to achieve the effective water management of the Yongdam dam and the Daecheong dam by using the developed cascaded model.

• Wind and Structures
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• 제12권4호
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• pp.313-332
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• 2009

This paper numerically and experimentally investigates the control performance of the active mass damper (AMD) systems in a 26-story high-rise building in use. This is the first full-scale application of the AMD system for suppressing the wind-induced vibration of a building structure in Korea. In addition, the AMD system was installed on top of the building already in use, which may be the world's first implementation case. In order to simultaneously mitigate the transverse-torsional coupled vibration of the building, two AMD systems were applied. Moreover, the H-infinity control algorithm has been developed to utilize the maximum capacity of the AMD system. From the results of numerical simulation using the wind load obtained from the wind tunnel tests, it was found that the maximum acceleration responses of the building were reduced significantly. Moreover, the control performance of the installed AMD system was examined by carrying out the free and forced vibration tests. The acceleration responses on top of the building in the controlled case measured under strong wind loads were compared with those in the uncontrolled case numerically simulated by using the wind load deduced from the measured data and a structural model of the building. It is demonstrated that the AMD system shows good control performance in reducing the building accelerations.

• 국제학술발표논문집
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• The 3th International Conference on Construction Engineering and Project Management
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• pp.203-211
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• 2009

Korean public owners who order public multi-family housing construction projects have yet to gain access to a model for predicting construction cost. For this reason, their construction cost prediction is mainly dependent upon historic data and experience. In this paper, a cost-prediction model based on Case-Based Reasoning (CBR) in the design phase of public multi-family housing construction projects was developed. The developed model can determine the total construction cost by estimating the different Building, Civil, Mechanical, Electronic and Telecommunication, and Landscaping work costs. Model validation showed an accuracy of 97.56%, confirming the model's excellent viability. The developed model can thus be used to predict the construction cost to be shouldered by public owners before the design is completed. Moreover, any change orders during the design phase can be immediately applied to the model, and various construction costs by design alternative can be verified using this model. Therefore, it is expected that public owners can exercise effective design management by using the developed cost prediction model. The use of such an effective cost prediction model can enable the owners to accurately determine in advance the construction cost and prevent increase or decrease in cost arising from the design changes in the design phase, such as change order. The model can also prevent the untoward increase in the duration of the design phase as it can effectively control unnecessary change orders.

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 2002년도 춘계학술대회 및 임시총회
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• pp.81-86
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• 2002

In current CBR(Case-Based Reasoning) systems, the case adaptation is usually performed by rule-based method that use rules hand-coded by the system developer. So, CBR system designer faces knowledge acquisition bottleneck similar to those found in traditional expert system design. In this thesis, 1 present a model for learning method of case adaptation knowledge using case base. The feature difference of each pair of cases are noted and become the antecedent part of an adaptation rule, the differences between the solutions in the compared cases become the consequent part of the rule. However, the number of rules that can possibly be discovered using a learning algorithm is enormous. The first method for finding cases to compare uses a syntactic measure of the distance between cases. The threshold fur identification of candidates for comparison is fixed th the maximum number of differences between the target and retrived case from all retrievals. The second method is to use similarity metric since the threshold method may not be an accurate measure. I suggest the elimination method of duplicate rules. In the elimination process, a confidence value is assigned to each rule based on its frequency. The learned adaptation rules is applied in riven target Problem. The basic. process involves search for all rules that handle at least one difference followed by a combination process in which complete solutions are built.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2007년 가을학술발표회
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• pp.514-527
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• 2007

Earth reinforcement techniques are used worldwide and offer proven solutions to a wide range of geotechnical engineering problems. Here in this paper, recent developments of three major reinforced soil retaining wall methods in Japan were introduced in order to show how the current situation of this technique in Japan is. And the statistical data for the volume of the use was also shown, such as the total volume of the use, the scales of the structures, layout of the earth reinforcement, fill materials, and foundation conditions. Some of the case histories were also introduced with photographs and figures. And then, as one of recent research activity by the author, the study on the application of X-ray CT for the problem of earth reinforcement method combined with other method such as piling and soil improvement was introduced. In this study, a series of model test for several reinforced ground with geogrids was conducted using a newly developed test apparatus. Then, the behavior in the soil box was scanned after settlement using X-ray CT scanner. Based on these test results, the reinforcing effect by the geogrids and the soil arching effect over the pile heads was discussed precisely and those are done in 3-D with nondestructive condition. Finally, the effectiveness of the use of X-ray CT scanner in geotechnical engineering was promised.

• The Journal of Asian Finance, Economics and Business
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• 제7권2호
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• pp.205-212
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• 2020

The article aims to identify the main factors affecting customers' decision to use mobile banking service in Vietnam, a case study in Thanh Hoa province. Based on theoretical frameworks of the Technology Acceptance Model (TAM) and the Unified Theory of Acceptance and Use of Technology (UTAUT), the study has been conducted with 370 questionnaires to consumers who have not yet used and are currently using mobile banking in Thanh Hoa province. The research results indicates that several factors have been evaluated to be more important than others, of which, the social influence is the strongest, the second is the compatibility and some others factors such as perceived ease of use, perceived trust, etc., all affecting the intention to use mobile banking in Thanh Hoa. Based on these important results, the article propose a number of recommendations: (i) Exploiting the advantages of social influence on the increase of intention to use; (ii) Increasing compatibility and minimizing costs for customers when they use Mobile Banking; (iii) Developing a strategy to increase the users' perceived ease of using banking services; (iv) Issuing a policy on increasing the security of Mobile Banking system to meet customers' needs; and (v) Developing an individual customer management system to improve service quality.

• 한국전자거래학회지
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• 제6권3호
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• pp.63-80
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• 2001

The construction of the students knowledge in e-Learning systems, namely the student modeling, is a core component used to develop e-Learning systems. However, existing e-Learning systems have many problems to share the knowledge in a heterogeneous student model and a distributed knowledge base. Because the methods of the knowledge representation are different in each e-Learning systems, the accumulated knowledge cannot be used or shared without a great deal of difficulty. In order to share this knowledge, existing systems must reconstruct the knowledge bases. Consequently, we propose a new a Case Markup Language based on XML in order to overcome these problems. A distributed e-Learning systems fan have the advantage of easily sharing and managing the heterogeneous knowledge base proposed by CaseML. Moreover students can generate and share a case knowledge to use the communication protocol of agents. In this paper, we have designed and developed a CaseML by using a knowledge markup language. Furthermore, in order to construct an intelligent e-Learning systems, we have done our research based on the design and development of the intelligent agent system by using CaseML.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2001년도 추계학술발표논문집 (상)
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• pp.363-366
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• 2001

It is very difficult to maintain the performance of estimation models for the new breed of projects since the computing environment changes so rapidly in terms of programming languages, development tools, and methodologies. So, we propose to use the relevant cases for a neural network model, whose cost is the decreased number of cases. To balance the relevance and data availability, the qualitative input factors are used as criteria of data classification. With the data sets that have the same value for certain qualitative input factors, we can eliminate the factors from the model making reduced neural network models. So we need to seek the optimally reduced neural network model among them. To find the optimally case-selective neural network, we propose the search techniques and sensitivity analysis between data points and search space.

• 산업경영시스템학회지
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• 제14권23호
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• pp.47-55
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• 1991

In automated assembly line, an automatic guided vehicle system(AGVS) represents a mire versatile means of moving materials automatically. In this paper, the vehicles not only provide the transportation medium between workstations but also as mobile workstations. The objective for the developed model is the determination of the appropriate time to control AGV based assembly line in order to minimize production makespan while maximizing the efficient use of vehicles. In this paper, we consider the finished goods of two types which are produced in assembly line. The assembly line is considered with and without queue. Because no buffer are present in case 1. this model seeks to determine the point in time at which vehicles should be launched in the assembly line without experiencing a delay. The case 2 model also seek to determine the vehicle launch times while minimizing production makespan. The assumption in this model is that the maximum queue size cannot exceed 1 at any time.

• 대기
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• 제26권1호
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• pp.141-158
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• 2016

The objective of this study is to examine the impact of urban canopy and the horizontal resolution on simulated meteorological variables such as 10-m wind speed, 2-m temperature and precipitation using WRF model for a local, convective rainfall case. We performed four sensitivity tests by varying the use of urban canopy model (UCM) and the horizontal resolution, then compared the model results with observations of AWS network. The focus of our study is over the Seoul metropolitan area for a convective rainfall that occurred on 16 August 16 2015. The analysis shows that mean diurnal variation of temperature is better simulated by the model runs with UCM before the convective rainfall. However, after rainfall, model shows significant difference in air temperature among sensitivity tests depending on the simulated rainfall amount. The rainfall amount is significantly underestimated in 0.5 km resolution model run compared to 1.5 km resolution, particularly over the urban areas. This is due to earlier occurrence of light rainfall in 0.5 km resolution model. Earlier light rainfall in the afternoon eliminates convective instability significantly, which prevents occurrence of rainfall later in the evening. The use of UCM results in a higher maximum rainfall in the domain, which is due to higher temperature in model runs with urban canopy. Earlier occurrence of rainfall in 0.5 km resolution model is related to rapid growth of PBL. Enhanced mixing and higher temperature result in rapid growth of PBL, which provides more favorable conditions for convection in the 0.5 km resolution run with urban canopy. All sensitivity tests show dry bias, which also contributes to the occurrence of light precipitation throughout the simulation period.