• Communications for Statistical Applications and Methods
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• v.12 no.1
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• pp.191-197
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• 2005

Application of data mining techniques to the world wide web, referred to as web mining, has been the focus of several recent researches. With the explosive growth of information sources available on the world wide web, it has become increasingly necessary to track and analyze their usage patterns. In this study, we introduce a process of pre-processing and cluster analysis on web log data and suggest a distance measure considering the structural relationships between web contents. Also, we illustrate some real examples of cluster analysis for web log data and look into practical application of web usage mining for eCRM.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2003.04a
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• pp.427-439
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• 2003

A previous study evaluated the seismic response of typical multi-span simply supported (MSSS) and multi-span continuous (MSC) steel-girder bridges in the central and southeastern United States. The results showed that the bridges were vulnerable to damage resulting from impact between decks, and large ductility demands on nonductile columns. Furthermore, fixed and expansion bearings were likely to fail during strong ground motion. In this paper, several retrofit measures to improve the seismic performance of typical multi-span simply supported and multi-span continuous steel girder bridges are evaluated, including the use of elastomeric bearings, lead-rubber bearings, and restrainer cables. It is determined that lead-rubber bearings are the most effective retrofit measure for reducing the seismic vulnerability of typical bridges. While isolation provided by elastomeric bearings limits the forces into the columns, the added flexibility results in pounding between decks in the MSSS steel-girder bridge. Restrainer cables, which are becoming a common retrofit measure, are only moderately effective in reducing the seismic vulnerability of MSSS and MSC steel girder bridges.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2006.04a
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• pp.71-76
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• 2006

In this paper, a long gauge Fiber Bragg Grating (FBG) sensor system is described and long gauge FBGs are well, suited for measuring the upper parts of the bridge piers under the extremely severe movement conditions. In the experiments, we used more than 30m long FBG sensors to measure the movement of top part of the bridge piers which are separated from the main bridge by cutting the decks. With the actuator, the deck and girders were pushed and released. We checked the movement of the top of the pier while releasing the pressure of the actuator with the long gauge fiber sensor. In order to measure the movement of the upper part of the pier, the reference point must be outside of the pier. Using the optical fiber sensors, one end of the sensor is attached to the top of the pier and the other end is attached to the bottom of the next pier. The fiber sensors showed good response to the release loading and we could calculate the movement of the top part of the pear.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2006.04a
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• pp.82-88
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• 2006

In People usually think that smart materials and smart structures have not been developed until recent years. But those kinds of sensors have already been used for sensing damage in a variety of materials and structures. Two typical examples are piezoelectric materials (e.g., PZT) and electric strain gauges. Load cell is an example that utilizes the piezoelectric property to measure the change in physical quantities occurred by applied loads, while strain gauges are used to measure the deformation of compressive and tension members. The feasibility of using smart materials is realized for a monitoring technology when those sensors are used to monitor damages at inside or outsider of the structures. In this study, a fundamental study on the development of self diagnostic smart concrete using PZT, and unsaturated polyester electric resistance sensor.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1998.10a
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• pp.167-174
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• 1998

It is important to measure e dynamic behaviors of the structures and determine the safety and serviceability of those structures by analyzing the gathered data. It is very much easier and more economical to measure the accelerations than displacements in order to obtain the dynamic responses of a structure, but the physical meanings of the displacements are more clear and definite than those of accelerations. In this study, the algorithm which can evaluate the displacements from the measured acceleration data by integration are developed. The calculated displacements are compared with measured data through the laboratory test and the results represent good agreements. This algorithm is applied to the data of real structures.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.11b
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• pp.1073-1077
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• 2001

The objective of this paper is to apply an experimental method based on the principle of reciprocity to measuring the structural intensity. Since only one accelerometer is used in this method it has the advantages of shortening measurement time. reducing accelerometer phase error. overcoming the limitation that the situation should be stationary during the experiment. It has been used to measure the vibration intensity of an infinite beam (beam with damped ends) and a semi-infinite beam (beam with simply supported and damped ends). Results showed that the experiment method based on the principle of reciprocity can be effectively used to measure the structural intensity.

• Journal of the Korean Society of Food Culture
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• v.23 no.1
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• pp.48-54
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• 2008

The purpose of this study was to measure the factors influencing customers’ value perception of foodservice in tourist area’s restaurant. A total of 273 questionnaires were completed. Structural equation model was used to measure the causal effects. Results of the study demonstrated that the confirmatory factor analysis model also indicated excellent model fit. The proposed model yielded a significantly better fit to the data than the parsimonious model and extended model. In proposed model, the effects of perceived sacrifice, overall service quality and customer satisfaction on perceived value were statistically significant. The effects of perceived value on loyalty intention were statistically significant. As expected, the overall service quality had a significant effect on customer satisfaction. Moreover, the customer satisfaction played a mediating role in the relationship between overall service quality and loyalty intention.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2005.04a
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• pp.680-687
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• 2005

This study presents a schema matching technique which can be applied to XML semantic model of structural calculation reports of steel-box bridges. The semantic model of structural calculation documents was developed by extracting the optimized common elements from the analyses of various existing structural calculation documents, and the standardized semantic model was schematized by using XML Schema. In addition, the similarity measure technique and the relaxation labeling technique were employed to develop the schema matching algorithm. The former takes into account the element categories and their features, and the latter considers the structural constraints in the semantic model. The standardized XML semantic model of steel-box bridge's structural calculation documents called target schema was compared with existing nonstandardized structural calculation documents called primitive schema by the developed schema matching algorithm Some application examples show the importance of the development of standardized target schema for structural calculation documents and the effectiveness and efficiency of schema matching technique in the examination of the degree of document standardization in structural calculation reports.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.2
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• pp.172-180
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• 2008

The purpose of this study was to measure the causal relationships among food involvement, health, mood, convenience, sensory appeal, weight control, and fruit consumption. A total of 290 questionnaires were completed. A structural equation model was used to measure the causal effects of the constructs, and the structural analysis results for the data indicated an excellent model fit. The effects of food involvement on health, mood, convenience, sensory appeal, weight control, and fruit consumption were statistically significant. As expected, health, mood, and weight control had significant effects on fruit consumption. Moreover, food involvement had a significant indirect effect on fruit consumption through health, mood, convenience, sensory appeal and weight control. For the future development and testing of conceptual models that integrate the relationships among personality traits, food choice motives, and fruit consumption, this study may approach a deeper understanding of the complex relationships among fruit consumption behavior-related variables. Greater understanding of these complex relationships can improve the managerial diagnosis of the problem and opportunities for different marketing strategies, including fruit production and fruit product development and marketing communications.

• Smart Structures and Systems
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• v.3 no.3
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• pp.373-384
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• 2007

For structural health monitoring (SHM) of civil infrastructures, displacement is a good descriptor of the structural behavior under all the potential disturbances. However, it is not easy to measure displacement of civil infrastructures, since the conventional sensors need a reference point, and inaccessibility to the reference point is sometimes caused by the geographic conditions, such as a highway or river under a bridge, which makes installation of measuring devices time-consuming and costly, if not impossible. To resolve this issue, a visionbased real-time displacement measurement system using digital image processing techniques is developed. The effectiveness of the proposed system was verified by comparing the load carrying capacities of a steel-plate girder bridge obtained from the conventional sensor and the present system. Further, to simultaneously measure multiple points, a synchronized vision-based system is developed using master/slave system with wireless data communication. For the purpose of verification, the measured displacement by a synchronized vision-based system was compared with the data measured by conventional contact-type sensors, linear variable differential transformers (LVDT) from a laboratory test.