• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2000.10a
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• pp.278-287
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• 2000

In Korea, countermeasures against earthquake disasters such as the seismic performance evaluation and/or retrofit scheme of buildings have not been fully performed since Korea had not been experienced many destructive earthquakes in the past. However, due to more than four hundred earthquakes with slight/medium intensity occurred in the off-coastal and inland of Korea during the past 20 years, and due to the great earthquakes occurred recently in neighboring countries, such as the 1995 Hyogoken-Nambu Earthquake with more than 6,500 fatalities in Japan and the 1999 Ji-Ji Earthquake with more than 2,500 fatalities in Taiwan, the importance of the future earthquake preparedness measures in Korea is highly recognized. The main objective of this paper is to provide the basic data for development of a methodology for the future earthquake preparedness in Korea by investigating the concept and applicabilities of the Japanese Standard for Evaluation of Seismic Performance of Existing RC Buildings developed in Japan among the methodologies of all over the world. In this paper, a seismic performance evaluation method of the existing reinforced concrete buildings is proposed based on experimental data of columns and walls carried out in Korea by referring the Japanese Standard, especially focusing on the Strength Index(C) among the indices in the seismic capacity index(IS) equations. Also, the seismic capacities of two existing reinforced concrete buildings in Korea are evaluated based on the proposed methodology and the Japanese Standard, and the correlations between the seismic capacities by the proposed methodology and the Japanese Standard are discussed.

• Journal of Advanced Marine Engineering and Technology
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• v.35 no.8
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• pp.1035-1040
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• 2011

In this study, many researches have been carried out against Energy Efficiency Operational Indicator(EEOI) of existing ships under discussion by IMO. This research is examined the method for the polices about IMO's greenhouse gas reducing emissions among them, we were analyzed the EEOI for existing ships. we have analyzed the result about applying EEOI using the calculation method of the rate of fuel consumption for cargo quantities to the actual existing ships and raised the problem. Based on this research, we were presented the improved EEOI about the engine load using fuel consumption and applied the existing ships. As a result, we concluded that the improved EEOI can define a resonable rate of $CO_2$ emissions.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.30 no.6_2
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• pp.623-629
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• 2012

During the construction of crossing engineering one of the important measures to ensure the safety of subway operation is the implementation of deformation surveying to the existing subway tunnel. Guangzhou new subway line 2 engineering which crosses the existing tunnel is taken as the background. How to achieve intelligent and automatic deformation surveying forecast during the subway tunnel construction process is studied. Because large amount of surveying data exists in the subway construction, deformation analysis is difficult and prediction has low accuracy, a subway intelligent deformation prediction model based on the PBIL and support vector machine is proposed. The PBIL algorithm is used to optimize the exact key parameters combination of support vector machine though probability analysis and thereby the predictive ability of the model deformation is greatly improved. Through applications on the Guangzhou subway across deformation surveying deformation engineering the prediction method's predictive ability has high accuracy and the method has high practicality. It can support effective solution to the implementation of the comprehensive and accurate surveying and early warning under subway operation conditions with the environmental interference and complex deformation.

• Earthquakes and Structures
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• v.9 no.6
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• pp.1337-1353
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• 2015

Seismic upgrading of existing structures is a technical and social issue aimed at risk reduction. Sustainable design is one of the most important challenges in any structural project. Nowadays, many retrofit strategies are feasible and several traditional and innovative options are available to engineers. Basically, the design strategy can lead to increase structural ductility, strength, or both of them, but also stiffness regulation and supplemental damping are possible strategies to reduce seismic vulnerability. Each design solution has different technical and economical performances. In this paper, four different design solutions are presented for the retrofit of an existing RC frame with poor concrete quality and inadequate reinforcement detailing. The considered solutions are based on FRP wrapping of the existing structural elements or alternatively on new RC shear walls introduction. This paper shows the comparison among the considered design strategies in order to select the suitable solution, which reaches the compromise between the obtained safety level and costs during the life-cycle of the building. Each solution is worked out by considering three different levels of seismic demand. The structural capacity of the considered retrofit solutions is assessed with nonlinear static analysis and the seismic performance is evaluated with the capacity spectrum method.

• Korean Management Science Review
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• v.21 no.2
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• pp.61-77
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• 2004

As various methodologies for business process analysis and design have been conducted in many organizations by their own ways, those methodologies are not compatible each other. In order to reduce the cost of analysis for organizations. some mapping methods between different methodologies need to be developed. UMM(UN/CEFACT Modeling Methodology) that has an object-oriented point of view. can overcome the limits of existing bottom-up approaches and make it reasonable. It also simplifies the business and administrative procedures. IDEF( Integrated Definition Language) with a structural point of view that has been widely used as a system analysis and design method, needs to be mapped to UMM in order to reuse the existing IDEF models. In this study, we propose a guideline that deals with procedures of utilizing IDEF models from which we want to derive the UMM models for developing an electronic commerce system including electronic documents exchange. By comparing IDEF and UMM, we analyze the differences between those two methodologies. Based on these differences. we suggest the basic strategies for mapping method from IDEF to UMM. We also propose a mapping guideline that can make UMM results from the modeling results of IDEF. We can take an advantage of the existing IDEF analysis design results when we adopt UMM methodology for electronic business system. Many analysts who are familiar with the IDEF methodology can develop UMM work-flow by utilizing their existing results and skills.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.5
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• pp.1025-1030
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• 2011

To improve the performance of mobile communication systems, beamforming technology is being considered. However, the number of antenna should be more than four to implement beamforming technology. Therefore, the existing 2-Tx RU (radio unit) for $2{\times}2$ MIMO (multiple input multiple output) should be replaced by 4-Tx RU for beamforming function. In this paper, we propose a new method to implement 4-Tx beamforming RU reusing the existing 2-Tx RU. We think that our method is very useful from the viewpoint of cost and environment because the existing 2-Tx RUs can be reused.

• Journal of Korean Society of Transportation
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• v.21 no.2
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• pp.119-130
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• 2003

SP data have been widely used in assessing new transport policies and transport related plans. However, one of criticisms of using SP is that respondents may show different reaction between hypothetical experiments and real life. In order to overcome the problem, combination of SP and RP data has been suggested and the combined methods have been being developed. The purpose of this paper is to suggest a new SP and RP combined method using error component method and to verify the method. The error component method decomposes IID extreme value error into non-IID error component(s) and an IID error component. The method estimates both of component parameters and utility parameters in order to obtain relative variance of SP data and RP data. The artificial SP and RP data was created by using simulation and used for the analysis, and the estimation results of the error component method were compared with those of existing SP and RP combined methods. The results show that regardless of data size, the parameters of the error component method models are similar to those assumed parameters much more than those of the existing SP and RP combined models, indicating usefulness of the error component method. Also the values of time for error component method are more similar to those assumed values than those of the existing combined models. Therefore, we can conclude that the error component method is useful in combining SP and RP data and more efficient than the existing methods.

• Proceedings of the KIEE Conference
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• 2003.11a
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• pp.488-490
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• 2003

This paprer presents the evlauation method for transmission marginal loss factors(MLFs) considering the electrical distance. Generally, MLFs are represented as the sensitivity of transmission losses, which is computed from the change of generation by the change of the load. MLFs are classified as load-focused MLFs and generator-focused MLFs. The existing evaluation method for generator focused MLFs has the limit not reflecting the characteristic of power systems since the method has been introduced the assumption which the output of a generator is supplied to all of the load buses on the power system. Therefore, to overcome the limit of evaluation method for generator-focused MLFs, we have applied the process, which it approximately can find the load buses that supplied a generator to the method. We have applied the proposed method to the simple 5-bus system because the proposed method is not analytic but the hybrid method incorporated the Kirschen and Bialek's algorithm to the existing analytic method to find the load buses supplied by a generator.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2000.04a
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• pp.267-274
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• 2000

Current seismic design codes for building structures are based on the method which can provide enough capacity to satisfy objected performance level and exactly evaluate the seismic performance of buildings. The capacity spectrum method using the nonlinear static(pushover) analysis is becoming a popular tool for evaluating the seismic performance of existing and new building structures. By means of a graphical procedure capacity spectrum method esimates the performance level of structure by comparing the capacity of structure with the demand of earthquake ground motion on the structure. In the method the relation between base shear estimated by a nonlinear static analysis and horizontal displacement is used. Capacity spectrum is usually expressed as what represent the responses of the equivalent single degree of freedom (ESDOF) system for the building structures. However there are some problems in converting procedures into ESDOF system which include not considering the effect of higher modes of structures. The objective of this paper is to compare and verify existing methods and suggest the modified capacity spectrum for seismic performance evaluation of building structures.

• Journal of Information Science Theory and Practice
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• v.5 no.3
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• pp.31-47
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• 2017

The narrow-down approach, separately composed of search and classification stages, is an effective way of dealing with large-scale hierarchical text classification. Recent approaches introduce methods of incorporating global, local, and path information extracted from web taxonomies in the classification stage. Meanwhile, in the case of utilizing path information, there have been few efforts to address existing limitations and develop more sophisticated methods. In this paper, we propose an expansion method to effectively exploit category path information based on the observation that the existing method is exposed to a term mismatch problem and low discrimination power due to insufficient path information. The key idea of our method is to utilize relevant information not presented on category paths by adding more useful words. We evaluate the effectiveness of our method on state-of-the art narrow-down methods and report the results with in-depth analysis.