• Structural Engineering and Mechanics
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• v.49 no.1
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• pp.111-128
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• 2014

The stochastic response surface method (SRSM) and the response surface method (RSM) are often used for structural reliability analysis, especially for reliability problems with implicit performance functions. This paper aims to compare these two methods in terms of fitting the performance function, accuracy and efficiency in estimating probability of failure as well as statistical moments of system output response. The computational procedures of two response surface methods are briefly introduced first. Then their capabilities are demonstrated and compared in detail through two examples. The results indicate that the probability of failure mainly reflects the accuracy of the response surface function (RSF) fitting the performance function in the vicinity of the design point, while the statistical moments of system output response reflect the accuracy of the RSF fitting the performance function in the entire space. In addition, the performance function can be well fitted by the SRSM with an optimal order polynomial chaos expansion both in the entire physical and in the independent standard normal spaces. However, it can be only well fitted by the RSM in the vicinity of the design point. For reliability problems involving random variables with approximate normal distributions, such as normal, lognormal, and Gumbel Max distributions, both the probability of failure and statistical moments of system output response can be accurately estimated by the SRSM, whereas the RSM can only produce the probability of failure with a reasonable accuracy.

• Earthquakes and Structures
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• v.16 no.6
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• pp.641-654
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• 2019

This paper investigates the seismic response of a typical non-navigable continuous girder bridge isolated with friction sliding bearings of the Hong Kong-Zhuhai-Macao link projects in China. The effectiveness of the friction pendulum system (FPS) and accuracy of the numerical model were evaluated by a 1/20 scaled bridge model using shaking table tests. Based on the hysteretic properties of friction pendulum system (FPS), double concave friction pendulum (DCFP), and triple friction pendulum system (TFPS), seismic response analyses of isolated bridges with the three sliding-type bearings are systematically carried out considering soil-pile interaction under offshore soft clay conditions. The fast nonlinear analysis (FNA) method and response spectrum are employed to investigate the seismic response of isolated offshore bridge structures. The numerical results show that the implementation of the three sliding-type bearings effectively reduce the base shear and bending moment of the reinforced concrete pier, at the cost of increasing the absolute displacement of the bridge superstructure. Furthermore, the TFPS and DCFP bearings show better isolation effect than FPS bearing for the example continuous girder bridge.

• Animal cells and systems
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• v.8 no.4
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• pp.295-300
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• 2004

In the breeding colony of black-tailed gull, as nests of conspecific neighbors are very closely located, chicks are permanently exposed by sound and visual stimuli produced by adult conspecifics approaching their nests. The chicks, therefore, may need to learn ways to appropriately respond to their parents approach. In this study we experimentally manipulated sensory stimulation that is potentially provided by the parents to the offspring. Chicks incubated in the laboratory were exposed to a mew call of the conspecific adult. Then they were tested in three situations differing in sensory stimulation: 1) visual stimulation only, 2) auditory stimulation only, and 3) Simultaneous visual and auditory stimulations. We observed occurrence of different response of the chicks, which were categorized into three behaviors (begging call response, chirirah call and pecking behavior). We also investigated intensity of the chicks call in response to the different stimulations and the degree of response with age. The chicks exposed to only auditory stimulation made significantly more chirirah calls. The intensities (dB) of the mew call and chicks chirirah call were directly correlated. On the other hand, when chicks just saw the stuffed adult gull, they responded significantly more with a begging call and pecking behavior. In the situation of costimulation, the chicks responded with a begging call and pecking, but less frequently than visual stimulation only. The results suggest that young black-tailed gulls use call repertories to properly respond to parents behavior. Such results suggest an evolutionary process for uncreasing their survival rate in a group breeding site.

• Journal of Korean Elementary Science Education
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• v.34 no.1
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• pp.15-31
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• 2015

The purpose of this study was to investigate elementary student teachers' conceptions about the mechanism of the greenhouse effect, the greenhouse gases, the global warming, and their learning experiences of the greenhouse effect and the global warming. Participants were 82 student teachers in their second year of studies (science education: n=28, not science education: n=27) and in their fourth year of studies (science education: n=27). The open-ended questionnaire was used to examine the teachers' spontaneous ideas depicted by their drawings and/or writings. The results of this study are as follows: First, the student teachers' scientific response rate about key concepts related to the mechanism of the greenhouse effect was low (6.1%~28.0%); Second, although there are various greenhouse gases, it was only carbon dioxide that the student teacher's response rate was more than 80%; Third, only 17.1% of the student teachers clearly distinguished the greenhouse effect and the global warming; Fourth, there was a tendency that the student teacher group in the fourth year of studies and science education showed higher scientific response rate about the concepts than the other two groups.

• Structural Engineering and Mechanics
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• v.75 no.2
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• pp.145-155
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• 2020

This paper investigates the influence of spatial varations of accidental mass eccentricities on the torsional response of inelastic multistorey reinforced concrete buildings. It complements recent studies on the elastic response of structural buildings and extends the investigation into the inelastic range, with the aim of providing guidelines for minimising the torsional response of structural buildings. Four spatial mass eccentricity configurations of common nine story buildings, along with their reversed mass eccentricities subjected to the Erzincan-1992 and Kobe-1995 ground motions were investigated, and the results are discussed in the context of the structural response of the no eccentricity models. It is demonstrated that when the initial linear response is practically translational, it is maintained into the inelastic phase of deformation as long as the strength assignment of the lateral resisting bents is based on a planar static analysis where the applied lateral loads simulate the first mode of vibration of the uncoupled structure.

• Journal of Fisheries and Marine Sciences Education
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• v.22 no.1
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• pp.113-122
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• 2010

This research was to survey and analyze the recognition about combination indication subject of secondary school teacher's certificate in the vocation high school. The conclusion through this research results are as follows, First, The satisfaction of qualification training about combination indication subject was a general positive response(77.5%), but there was partly negative response(5.2%). Second, The efficiency of qualification training curriculum was positive response(62%), the high response(77.7%) was the fisheries affiliate. It was probably good because of simulation of ship sailing about practice curriculum. Third, The need of qualification training on combination indication subject for vocational high school teacher was positive response(81%), but negative response(3.4%)

• Geomechanics and Engineering
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• v.23 no.3
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• pp.275-287
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• 2020

Rectangular barrettes have been increasingly used as foundations for many infrastructure projects, but the vertical vibration of a barrette has been rarely addressed theoretically. This paper presents an analysis method of dynamic response for a rectangular barrette subjected to a time-harmonic vertical force with the aid of a modified Vlasov foundation model in multilayered viscoelastic soil. The barrette-soil system is modeled as a continuum, the vertical continuous displacement model for the barrette and soil is proposed. The governing equations of the barrette-soil system and the boundary conditions are obtained and the vertical shaft resistance of barrette is established by employing Hamilton's principle for the system and thin layer element, respectively. The physical meaning of the governing equations and shaft resistance is interpreted. The iterative solution algorithm flow is proposed to obtain the dynamic response of barrette. Good agreement of the analysis and comparison confirms the correctness of the present solution. A parametric study is further used to demonstrate the effects of cross section aspect ratio of barrettes, depth of soil column, and module ratio of substratum to the upper soil layers on the complex barrette-head stiffness and the resistance stiffness.

• Journal of Engineering Education Research
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• v.26 no.3
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• pp.35-41
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• 2023

The study was conducted to develop two parallel short forms for the Convergent thinking and Problem solving questionnaires which are part of H University's core competency diagnostic tools, based on Multi-Item Response Theory. Item responses of 2,580 students were analyzed using Graded Response Model(GRM) to determine item difficulty and discrimination of each item. The research results are as follows. Two parrallel short tests were developed for the Convergent thinking questionnaire consisting of 12 items which were originally 17 items. Likewise, the Problem solving questionnaire, which originally consisted of 15 questions, was divided into two parallel short forms, each consisting of 9 items. The reliability of the shortened parallel tests was confirmed through internal consistency analysis, and their similarity to the original tests was established through correlation analysis. This study contributed to quality management of competency-based education and programs at H University by developing shortened tests. Based on the results, implications were presented as well as limitations and discussions.

• Proceedings of KOSOMES biannual meeting
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• 2017.04a
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• pp.197-197
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• 2017

• Journal of the Korean Society of Food Culture
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• v.19 no.6
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• pp.630-639
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• 2004

Korean households' expenditures on foodservices are on the steady increase. This paper aims to examine the foodservice expenditures of salary and wage earners's households by income decile group. This is analysed through comparing foodservice expenditures with private education expenditures because households' expenditures are likely to be weighted in favor of eating-out rather than private education. We also model the consumption function in terms of income and price, examining the responsiveness of private education demand and eating-out demand to changes in income and price using econometric methods such as regression, rolling regression and impulse response. This paper show that foodservice demand increases more than the private education does in the long-run. The result indicates that households are likely to evaluate the desire for foodservice more important than private education contrary to our expectations in the long-run. The impulse response analysis, however, suggests that households tend to increase private education expenditures rather than eating-out expenditures in the short-run.