• Steel and Composite Structures
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• v.46 no.3
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• pp.435-449
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• 2023

Time domain method and frequency domain method are commonly used in the current fatigue life calculation theory. The time domain method has complicated procedures and needs a large amount of calculation, while the frequency domain method has poor applicability to different materials and different spectrum, and improper selection of spectrum model will lead to large errors. Considering that artificial neural network has strong ability of nonlinear mapping and generalization, this paper applied this technique to random fatigue life prediction, and the effect of average stress was taken into account, thereby achieving more accurate prediction result of random fatigue life.

• Proceedings of the Korean Society for Bioinformatics Conference
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• 2005.09a
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• pp.339-343
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• 2005

Boolean networks(BN) construction is one of the commonly used methods for building gene networks from time series microarray data. However, BN has two major drawbacks. First, it requires heavy computing times. Second, the binary transformation of the microarray data may cause a loss of information. This paper propose two methods using liner regression to construct gene regulatory networks. The first proposed method uses regression based BN variable selection method, which reduces the computing time significantly in the BN construction. The second method is the regression based network method that can flexibly incorporate the interaction of the genes using continuous gene expression data. We construct the network structure from the simulated data to compare the computing times between Boolean networks and the proposed method. The regression based network method is evaluated using a microarray data of cell cycle in Caulobacter crescentus.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.4
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• pp.1911-1930
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• 2017

Overlay routing has emerged as a promising approach to improve reliability and efficiency of the Internet. The key to overlay routing is the placement and maintenance of the overlay infrastructure, especially, the selection and placement of key relay nodes. Spurred by the observation that a few relay nodes with high betweenness centrality can provide more optimal routes for a large number of node pairs, we propose a resilient routing overlay network construction method by introducing Super-Relay nodes. In detail, we present the K-Minimum Spanning Tree with Super-Relay nodes algorithm (SR-KMST), in which we focus on the selection and connection of Super-Relay nodes to optimize the routing quality in a resilient and scalable manner. For the simultaneous path failures between the default physical path and the overlay backup path, we also address the selection of recovery path. The objective is to select a proper one-hop recovery path with minimum cost in path probing and measurement. Simulations based on a real ISP network and a synthetic Internet topology show that our approach can provide high-quality overlay routing service, while achieving good robustness.

• International conference on construction engineering and project management
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• 2017.10a
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• pp.235-241
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• 2017

SWOT-AHP method was utilized in the research for the Korean construction companies to advance into the US PPP market. The research was that the SO Strategy ": Advancing through strategic selection of both construction sector type and region", ST Strategy "Advancing based on the acquired competitive business sector", WO Strategy "Developing collaboration model between public financial organization and construction company", and WT Strategy "Establihing a partnership or M&A with local companies".

• Journal of the Korean association of regional geographers
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• v.14 no.6
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• pp.752-766
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• 2008

For all the region is the basic unit of geographical learning and the grounds of human activities, regional learning can't possible be carried out at the class. Because there are very few regional learning materials that are applicable to class and can be expanded to geographical basic concept. This paper aims to regulate the construction principles of regional learning and select the contents of regional learning. Firstly, the six basic concepts of geographical education be made a selection of the construction principles of regional learning: human-environment, location, region, interaction, change, scale. And then, I suggest the upper five subject that be based on the results of systematical geography. Those are the necessity and method of regional apprehension, the physical environment and the regional human-life, the resource and industrial activities. the regional life-space's formation and change, and the changing world and region. And I propose the subdivided the mid and the lower subject that be reflected the learner's need and the social demand, and could be experienced the results of geography and the everyday life. For the best regional learning, these subjects can be combined one or more in various scale.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.1324-1327
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• 2009

Social infrastructure is the basis of public welfare and should be recognized and managed as important assets. Bridge is one of the most important infrastructures to be managed systematically because the impact of the failure is critical. It is essential to monitor the performance of bridges in order to manage them as an asset. But current analytical methods such as predictive modeling and structural analysis are very complicated and difficult to use in practice. To apply these methods, structural and material condition data collection should be performed in each element of bridge. But it is difficult to collect these detailed data in large numbers and various kinds of bridges. Therefore, it is necessary to collect data of major measurement items and predict the life of bridges roughly with advanced information technologies. When certain measurement items reach predefined limits in the monitoring bridges, precise performance measurement will be done by detailed site measurement. This paper describes the selection of major measurement items that can represent the tendency of bridge life and introduces automated bridge data collection test-bed using wireless sensor network technology. The following will be major parts of this paper: 1) Examining the features of conventional bridge management system and data collection method 2) Mileage concept as a bridge life indicator and measuring method of the indicator 3) Test-bed of automated and real-time based bridge life indicator monitoring system using wireless sensor network

• Journal of the Korea institute for structural maintenance and inspection
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• v.17 no.4
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• pp.101-111
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• 2013

In this study, DEA (Data Envelopment Analysis) was carried out on the four bridges, which have the same extension (L=1,615m), in order to select the most superior, economical method of construction using the LCC concept of each bridge structure in the case of the Ulsan-Pohang double track railway which is scheduled to be constructed. DEA models were analyzed with the CCR model, which was designed for the evaluation of relative efficiency of each model. The initial construction costs, maintenance costs, indirect costs (user costs + indirect loss of social costs), and life cycle costs were used as input variables, and average duration was applied as the output variable. LCC was applied to calculate the input variables, and to get the costs of LCC, 100 years of period and 4.83% of real discount rate were applied, and the costs are classified into initial construction, maintenance, user, and indirect loss of social cost. The analysis results showed that the Method 2 and 3 were evaluated as the most efficient, and the other alternatives were evaluated as the following order; Method 1, the default, and Method 4.

• Journal of Industrial Technology
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• v.18
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• pp.27-34
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• 1998

According to growing interest in environmental quality with improvements of a standard of living site selection problems such as waste landfill sites, caused regional conflicts. This study investigates a waste landfill estimation method that was used to for storage, management, analysis and display of environmental information provided by geo-spatial information system(GIS) and analytic hierarchy process(AHP) as a decision-making method. If GIS is integrated with AHP, site selection problems of environmental hatred facilities shall be able to be very useful, because of AHP with flexibility which appropriately reflects opinions of the related group.

• Proceedings of the KWS Conference
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• 2006.05a
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• pp.304-306
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• 2006

Positioning the workpiece accurately and preventing the weld distortion, tack welding is often performed before main welding in the construction of welded structures. The weld bead size of the tack weld is determined according to the workpiece thickness, weld length, weld joint type etc. However, this tack weld deteriorates the final weld bead profile, so that the grinding process is usually adopted for the uniform weld bead profile. In this study, an experimental method for the selection of optimal welding condition was proposed in the fillet weld which was done over the tack weld. This method uses the response surface analysis in which the leg length and the reinforcement height of weld bead were chosen as the quality variables of weld bead profile. The overall desirability function, which was combined desirability function for the two quality variables, was used as the objective function for getting the optimal welding condition. From the result, it was revealed that a uniform weld bead can be obtained by adopting the optimal welding condition which was determined according to the method proposed.

• Journal of Korean Society for Geospatial Information Science
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• v.5 no.1 s.9
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• pp.27-40
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• 1997

Recently, with the demand for airservice increasing and localization accelerating, airport construction is booming. However, in the case of an unsuitable airport site selection, it might cause a reduction in airport service and a decrease in airport demand. Thus, it is necessary to construct a representative airport and choose a suitable site selection method for economical and efficient airports in order to make the utmost use of airport functions. In this study, GSIS was used to select the airport site and applied to case study areas. GSIS could present a new method for efficient and scientific analysis in airport site selection including various factors over an extensive area. The use of both, the paired comparison method and the delphi method, could improve the objectivity of analysis results in the process considering the relative weight grade of data and priority order of analysis factors, used in airport site selection.