• Structural Engineering and Mechanics
• /
• v.39 no.6
• /
• pp.795-812
• /
• 2011

Estimation of damage probability of buildings under a future earthquake is an essential issue to ensure the seismic reliability. Fragility curves are useful tools for showing the probability of structural damage due to earthquakes as a function of ground motion indices. The purpose of this study is to compare the damage probability of R/C buildings with low and high level of strength and ductility through fragility analysis. Two different types of sample buildings have been considered which represent the building types mentioned above. The first one was designed according to TEC-2007 and the latter was designed according to TEC-1975. The pushover curves of sample buildings were obtained via pushover analyses. Using 60 ground motion records, nonlinear time-history analyses of equivalent single degree of freedom systems were performed using bilinear hysteretic model and peak-oriented hysteretic model with stiffness - strength deterioration for each scaled elastic spectral displacement. The damage measure is maximum inter-story drift ratio and each performance level considered in this study has an assumed limit value of damage measure. Discrete damage probabilities were calculated using statistical methods for each considered performance level and elastic spectral displacement. Consequently, continuous fragility curves have been constructed based on the lognormal distribution assumption. Furthermore, the effect of hysteresis model parameters on the damage probability is investigated.

• Journal of Environmental Impact Assessment
• /
• v.21 no.3
• /
• pp.391-407
• /
• 2012

The loss of connectivity and fragmentation of forest landscapes are seriously hindering dispersal of many forest-dwelling species, which may be critical for their viability and conservation by decreasing habitat area and increasing distance among habitats. For understanding their environmental impacts, numerous spatial models exist to measure landscape connectivity. However, general relationships between functional connectivity and landscape structure are lacking, there is a need to develop landscape metrics that more accurately measure landscape connectivity in whole landscape and individual patches. We reviewed functional and structural definition of landscape connectivity, explained their mathematical connotations, and applied representative 13 indices in 3 districts of Seoul having fragmented forest patches with tits, the threshold distance was applied 500m by considering the dispersal of tits. Results of correlation and principal component analysis showed that connectivity indices could be divided by measurement methods whether they contain the area attribute with distance or not. Betweenness centrality(BC), a representative index measuring distance and distribution among patches, appreciated highly stepping stone forest patches, and difference of probability of connectivity(dPC), an index measuring including area information, estimated integrated connectivity of patches. Therefore, for evaluating landscape connectivity, it is need to consider not only general information of a region and species' characteristics but also various measuring methods of landscape connectivity.

• Proceedings of the Computational Structural Engineering Institute Conference
• /
• 2006.04a
• /
• pp.159-166
• /
• 2006

Although the strain distribution along the length of a beam in buildings or infrastructures is non-uniform, most fiber optic sensors are point sensors that can measure the strain only at a local point of a beam. Long gage fiber optic sensors that measure integrated strain over a relatively long length can consider strain variation. This type of sensor was found to be efficient and useful for monitoring large-scale structures. On the other hand, the maximum strain or stress in a beam can not be measured with long gage optic sensors. However, for the assessment of the safety of multi-span steel beams subjected to various vertical loads, the maximum strain or stress measured during monitoring is required for comparison with the allowable stress of the beam calculated by a design code. Therefore, in this paper, mathematical models are presented for determination of the maximum values of strains in more three-span steel beams based on the average strains measured by long gage optic sensors.

• Journal of the East Asian Society of Dietary Life
• /
• v.17 no.5
• /
• pp.653-660
• /
• 2007

The purpose of this study was to measure the causal relationships among such variables as moral concerns for animals, meat texture, meat color, satiety from meat, disgust with meat and pork consumption. A total of 250 questionnaires were completed. Structural equation models were used to measure the causal effects of the constructs. The study outcomes demonstrated that the structural analysis results of the data were an excellent model fit. The effects of moral concerns for animals, meat texture and satiety from meat on the disgust with meat were statistically significant. As expected, disgust with meat had a significant effect on pork consumption. Moreover, moral concerns for animals and satiety from meat had a significant indirect effect on pork consumption through disgust with meat. Also, satiety from meat alone had a significant indirect effect on pork consumption through disgust with meat. By developing and testing conceptual models that integrated the relationships among ideational variables, sensory affective variables, anticipated consequences variables, emotional variables, and behavioral variables, this study may approach a deeper understanding of the complex relationships among pork consumption-related variables. A greater understanding of these complex relationships can improve the managerial diagnosis of problems as well as opportunities for different marketing strategies, including pork production and pork product development, and marketing communications.

• Earthquakes and Structures
• /
• v.15 no.4
• /
• pp.443-452
• /
• 2018

In this paper the new intensity measures (IMs) for probabilistic seismic analysis of RC high-rise buildings with core wall structural system are proposed. The existing IMs are analysed and the new optimal ones are presented. The newly proposed IMs are based on the existing ones which: 1) comprise a wider range of frequency velocity spectrum content and 2) are defined as the integral along the velocity spectrum. In analysis characteristics of optimal IMs such as: efficiency, practicality, proficiency and sufficiency are considered. As prototype buildings, RC high-rise buildings with core wall structural system and with characteristic heights: 20-storey, 30-storey and 40-storey, are selected. The non-linear 3D models of the prototype buildings are constructed. 720 non-linear time-history analyses are conducted for 60 ground motion records with a wide range of magnitudes, distances to source and various soil types. Statistical processing of results and detailed regression analysis are performed and appropriate demand models which relate IMs to demand measures (DMs), are obtained. The conducted analysis has shown that the newly proposed IMs can efficiently predict the DMs with minimum dispersion and satisfactory practicality as compared to the other commonly used IMs (e.g., PGA and $S_a(T_1)$). The newly proposed IMs overcome difficulties in calculating of integral along the velocity spectrum and present adequate replacement for IMs which comprise a wider range of frequency velocity spectrum content.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.16 no.6
• /
• pp.34-44
• /
• 2012

Many kind of sensors in the dam produce a lot of data associated with the maintenance and safety of the dam. So it is important to measure the reliability of the sensor (or measured data). In this paper, the new method using modified coherence function is proposed to measure the reliability of the sensor remotely. To verify feasibility of proposed method in the field, proposed method was applied to data of piezometer and earth pressure cell. Through field applications, the potential of the proposed method was verified.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.11 no.6
• /
• pp.181-192
• /
• 2007

In domestic case, there are no results of corresponding researches for measuring external tendon force. The purpose of the present paper is therefore to measure external tendon force by using deriving ultrasonic method. For this purpose, we designed and manufactured wedges and test system, and measured ultrasonic pulse velocity and pulse amplitude. By using measured data, we tried to analyze the characteristics of tendon force, and to derive the relationship between tendon force and ultrasonic pulse velocity, finally to develop the technic of measuring system using ultrasonic pulse velocity. So tendon force-velocity relationship was proposed by equations, and those equations of which errors were 3.92~8.77% will be possible to adapt in-site.

• Culinary science and hospitality research
• /
• v.14 no.2
• /
• pp.170-180
• /
• 2008

The purpose of this study was to measure the causal relationships between past consumption, health belief, subjective, attitude, intention and purchase of organic foods. Total 326 copies of questionnaire were completed. The structural equation model was used to measure the causal effect among constructs. The results demonstrated that the confirmatory factor analysis model provided a good model fit. The proposed model yielded a significantly better fit to the data than the baseline model and the extended model. The effects of past consumption, health belief and subjective norm on attitude and intention were statistically significant. The effects of attitude on intention and behavior to purchase organic food were statistically significant. As expected, health belief and subjective had significant effects on behavior to purchase organic foods. Moreover, past consumption, health belief and subjective norm had indirect influences on intention through mediated variables. Based on the empirical results and findings, some suggestions are provided to the institutions concerned so as to facilitate this organic sector's on-going expansion in the food industry.

• The Journal of Asian Finance, Economics and Business
• /
• v.7 no.11
• /
• pp.987-998
• /
• 2020

This study aims to examine OL as a potential mediating variable in the relationship between IT and organizational performance. Organizational learning (OL) has been proposed as the mechanism to accomplish this task. Existing empirical research demonstrates that OL may indeed act as a mediator for the effect of IT on organizational outcomes. Also, existing literature discusses the use of technology in the organization, and the case for OL as the key knowledge process, and the intersection between technology and OL as a knowledge-based means for improving organizational performance. Many studies use a descriptive measure of OL despite the theory suggesting that a normative measure may be more appropriate. This study aims to address these concerns in a setting by using structural equation modelling (SEM) to compare the effectiveness of descriptive and normative measures of OL as mediating variables in knowledge-intensive organizations. Survey results support OL as a mediator between IT and organizational performance in addition to normative measures of OL outperforming descriptive measures. Implications for research and practice are discussed. To test the model, we will apply (SEM) structural equation modeling in the analysis of a moment structures (AMOS) on the empirical evidence collected from 218 Pakistani CEOs and top managers.

• Journal of the East Asian Society of Dietary Life
• /
• v.17 no.6
• /
• pp.935-942
• /
• 2007

The purpose of this study was to measure the causal relationships among attitude toward eating seafood, perceived behavioral control (PBC), health involvement, behavioral intention and consumption. A total of 235 questionnaires were completed. A structural equation model was used to measure the causal effects of the constructs. The results of the study demonstrated that the structural analysis results for the data also indicated an excellent model fit. Health involvement had considerable effects on attitude and intention, which were statistically significant. The effects of attitude and PBC on intention were also statistically significant. Futhermore, the effects of attitude, PBC, and intention on consumption were statistically significant. As expected, intention had a significant effect on consumption. Moreover, health involvement had significant indirect effects on intention through attitude and PBC. Attitude had a significant indirect effect on consumption through intention. PBC also had a significant indirect effect on consumption through intention. By developing and testing conceptual models that integrated the relationship among variables such as health involvement and attitude, along with seafood consumption behavior, this study approaches a deeper understanding of how perceptions, on the importance of a healthy diet and other factors, influence consumption behavior.