• Journal of The Korean Society of Agricultural Engineers
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• v.48 no.6
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• pp.45-56
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• 2006

The finite element method is a practical tool to compute the response of the irregularly layered soil deposit to the base-rock motions. The method is useful not only in estimating the interaction between the structure and the surrounding soil as a whole and the local behavior of the contacting area in detail, but also in predicting the resulting behavior of the superstructure affected by such soil-structure interactions. However, the computation of finite element analysis is marched in the time domain (TD), while the site response analysis has been carried out mostly in the frequency domain (FD) with equivalent linear analysis. This study is intended to compare the results of the TD and FD analysis with focus on the peak response accelerations and the predominant frequencies, and thus to evaluate the applicability and the validity of the finite element analysis in the site response analysis. The comparison shows that one can obtain the results very close to that of FD analysis, from the finite element analysis by including sufficiently large width of foundation in the model and further by applying partial mode superposition. The finite element analysis turned out to be well agreeing with FD analysis in their computed results of the peak acceleration and the acceleration response spectra, especially at the surface layer.

• Geomechanics and Engineering
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• v.3 no.3
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• pp.189-206
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• 2011

Amplification based on empirical relations is widely used for seismic microzonation of urban centers. Amplifications are used to represent the site effects of a particular soil column. Many empirical correlations are available to estimate the amplification of seismic waves. These correlations are based on the ratio of shear wave velocity of foundation/rock to soil velocity or 30 m equivalent shear wave velocity ($Vs^{30}$) and are developed considering deep soil data. The aim of this work is to examine the applicability of available amplification relations in the literature for shallow engineering bedrock sites by carrying out site response studies. Shear wave velocity of thirteen sites having shallow engineering bedrock have been selected for the study. In these locations, the depth of engineering bedrock (> 760 ${\pm}$ 60 m/s) is matched with the drilled bore hole. Shear wave velocity (SWV) has been measured using Multichannel Analysis of Surface Wave survey. These sites are classified according to the National Earthquake Hazards Reduction Program (NEHRP) classification system. Amplifications for an earthquake are arrived for these sites using empirical relations and measured SWV data. Site response analysis has been carried out in SHAKE using SWV and using synthetic and real earthquake data. Amplification from site response analysis and empirical relations are compared. Study shows that the amplification arrived using empirical relations does not match with the site response amplification. Site response amplification is much more than empirical values for same shear wave velocity.

• Earthquakes and Structures
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• v.15 no.2
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• pp.193-202
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• 2018

This paper studied the probability of pounding occurred between decks and abutments of a long span high-pier continuous rigid fame bridge subjected to ground motions with local soil effect. A pounding probability analysis methodology has been proposed using peak acceleration at bedrock as intensity measure (IM) for multi-support seismic analysis. The bridge nonlinear finite element (FE) models was built with four different separation distances. Effect of actual site condition and non-uniform spatial soil profiles on seismic wave propagating from bedrock to ground surface is modelled. Pounding probability of the high-pier bridge under multi-support seismic excitations (MSSE) is analyzed based on the nonlinear incremental dynamic analysis (n-IDA). Pounding probability results under uniform excitations (UE) without actual local site effect are compared with that under MSSE with site effect. The study indicates that the required design separation length between deck and abutment under uniform excitations is larger than that under MSSE as the peak acceleration at bedrock increases. As the increase of both separation distance between deck and abutment and the peak acceleration, the probability of pounding occurred at a single abutment or at two abutments simultaneously under MSSE is less than that under UE. It is of great significance considering actual local site effect for determining the separation distance between deck and abutment through the probability pounding analysis of the high-pier bridge under MSSE.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.26 no.7
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• pp.30-38
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• 2012

Recently, interests in renewable energy have gradually increased. Photovoltaic system of various renewable energy is the most interest in power sources. Nowadays, the market of photovoltaic system is expected to be expanded due to the introduction of RPS(Renewable Portfolio Standard). Floating photovoltaic system is a new power system using the water surface above the dam and reservoir water. Floating photovoltaic system is different from the traditional approach to the development of solar power system causing problems such as environmental degradation. This paper investigates the analysis methods of suitable site for the development of floating photovoltaic system. The A,B,C as the optimal candidates were selected in hap cheon dam. The C is the best suitable site in A,B,C considering the expected power generation. Applied methods have effectively done to develop floated photovoltaic system.

• Journal of Mechanical Science and Technology
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• v.18 no.12
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• pp.2250-2257
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• 2004

The accurate wind speed information at the hub height of a wind turbine is very essential to the exact estimation of the wind turbine power performance testing. Several methods on the site calibration, which is a technique to estimate the wind speed at the wind turbine's hub height based on the measured wind data using a reference meteorological mast, are introduced. A site calibration result and the wind resource assessment for the TaeKwanRyung test site are presented using three-month wind data from a reference meteorological mast and the other mast temporarily installed at the site of wind turbine. Besides, an analysis on the uncertainty allocation for the wind speed correction using site calibration is performed.

• Journal of the Earthquake Engineering Society of Korea
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• v.28 no.5
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• pp.249-255
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• 2024

Strong ground motions at specific sites can cause severe damage to structures. Understanding the influence of site characteristics on the dynamic response of structures is crucial for evaluating their seismic performance and mitigating the potential damage caused by site effects. This study investigates the impact of the average shear wave velocity, as a site characteristic, on the seismic response of low-to-medium-rise reinforced concrete buildings. To explore them, one-dimensional soil column models were generated using shear wave velocity profile from California, and nonlinear site response analyses were performed using bedrock motions. Nonlinear dynamic structural analyses were conducted for reinforced concrete moment-resisting frame models based on the regional information. The effect of shear wave velocity on the structural response and surface ground motions was examined. The results showed that strong ground motions tend to exhibit higher damping on softer soils, reducing their intensity, while on stiffer soils, the ground motion intensity tends to amplify. Consequently, the structural response tended to increase on stiffer soils compared to softer soils.

• Journal of Information Technology Applications and Management
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• v.12 no.2
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• pp.145-161
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• 2005

In this paper, we present an experiment conducted to examine how the web site's architecture, content quantity and the user task complexity affect its usability. The experiment was performed in two phases on college students to visit existing web sites which are readily accessible via the Internet. The results of experiment show that the web site's architecture significantly affects the efficiency and the effectiveness interactively with its content quantity and the user task's complexity. On the other hand, none of the above three factors show significant effects on the satisfaction and the learnability. In particular, the web site's content quantity does not have any statistically significant effects on the satisfaction and the learnability. It implies that the factors affecting the satisfaction and the learnability are different from those affecting the efficiency and the effectiveness. The analysis reassures that it is essential to consider the context of use in designing a web site.

• Journal of Engineering Education Research
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• v.23 no.2
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• pp.49-60
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• 2020

The purpose of this study is to empirically verify whether there are differences according to group characteristics in the effect of job characteristic requirements on practice performance in university long-term on-site training. Specifically, the relationship between job characteristics (job scope, job content, coaching, benefits), practical satisfaction, and occupational competencies was examined according to the group characteristics (gender types, major types, corporation types). For this purpose, the survey data were collected and analyzed for 752 students who participated in K university long-term on-site training. As a result of the analysis, first, it was found that the job characteristics (job scope job content, coaching, benefits) had structural relationship affecting occupational competence through mediation of practice satisfaction. Second, As for the differences according to the group characteristics, there were differences in the relations. Based on the result, theoretical and practical implications and follow-up studies were proposed.

• The Korean Journal of Food & Health Convergence
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• v.5 no.6
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• pp.11-16
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• 2019

The construction environment has been declared as a hazard prone area due to high number of accident and death. The study aims to identify influential factors that contribute to poor safety practices and its consequences on construction workers in Cape Coast Metropolis. Seventy respondents were taken as the sample size for the study. Descriptive analysis was used to analyze the data obtained from the field. Findings show that poor site management, working without safety gadgets, failure to use their Personal Protective Equipment (PPE) and negligence of workers were the main causes of accidents on sites. Poor site management had the highest ranking among the seven variables. Effects of poor safety practices on building construction site and delays in work execution were due to injury of workers, extra cost due to payment of compensation to injured victims, not motivated due to injury of worker and declined reputation of firm. Management team should motivate workers for safe work done, provide adequate PPE for their workers on site and have documented health and safety policy on site. Site authorities and management team should be on site regularly to ensure proper safety practices on construction site.

• Journal of the Korea Society of Computer and Information
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• v.28 no.12
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• pp.249-257
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• 2023

In this paper, we propose ways how portal site POI(Point-of-Interest) contents by analyzing the effect of portal site POI contents attributes on favorability, satisfaction, and visit intention, and to propose a strategic marketing plan using portal site POI contents in restaurants. In this study, a survey was conducted on 300 people who had experience using portal site POI contents. Through prior research, the portal site POI contents attributes were classified into accuracy, authority, aesthetics, and currency. To verify the research hypothesis, single regression analysis and multiple regression analysis were conducted to confirm the relationship between variables. To summarize the core research results, first, the portal site POI contents attribute showed a positive relationship with favorability. Second, it was found that the portal site POI contents attribute had a positive relationship with satisfaction. Third, it was found that favorability had an effect on satisfaction. Fourth, it was found that favorability had an effect on the visit intention. Fifth, satisfaction was found to have an effect on the visit intention. Based on the analysis results, in order to induce customer visits in restaurants, it is necessary to make good use of portal site POI contents to increase user favorability and to allow users to visit stores.