Preliminary Study of the Unsteady Response Spectrum Based on Time-Varying

2011 ◽  
Vol 346 ◽  
pp. 58-62
Author(s):  
Pei Qiang ◽  
Ping Guan ◽  
Jing Tian ◽  
Er Liang Chen
Keyword(s):  
Seismic Analysis ◽  
Response Spectrum ◽  
Strong Motion ◽  
Maximum Response ◽  
Time Varying ◽  
Structural Failure ◽  
Time Duration ◽  
Structure Response ◽  
Preliminary Study ◽  
The Relationship

Engineering characteristics of ground motion can be defined by three factors that are respectively amplitude, frequency and duration. Any one of them in isolation are not fully made known for the ground notions affecting on the structure. Response spectrum theory is one of the principal methods in seismic analysis. The maximum response of structure under earthquake input is only varying with period in traditional response spectrum during the whole time duration. The relationship between the maximum response and duration can not be shown in the response spectrum of earthquake. The concept of unsteady response spectrum is based on moveable spectrum in this paper. Based on the conventional response spectrum, the factor of time is taken into account in unsteady response spectrum research. Then the response spectrum can be studied according to time varying. As examples for strong motion records obtained from WenChuan earthquake, two methods are proposed to research the effect of duration on response spectrum. The result of unsteady response spectrum can play an important role in the further study of the structural failure mechanism and cumulative damage under earthquake loadings.

scholarly journals An analysis of strong-motion accelerometer data from the San Francisco earthquake of March 22, 1957

1958 ◽  
Vol 48 (3) ◽  
pp. 253-268
Author(s):  
D. E. Hudson ◽  
G. W. Housner
Keyword(s):  
San Francisco ◽  
Response Spectrum ◽  
Ground Motions ◽  
Strong Motion ◽  
Geodetic Survey ◽  
Accelerometer Data ◽  
Structural Dynamic ◽  
Local Geology ◽  
The Relationship ◽  
Area Response

Abstract The San Francisco earthquake of March 22, 1957, was recorded simultaneously by accelerometers at five United States Coast and Geodetic Survey stations in the San Francisco area. Response spectrum curves were computed from the acceleration-time records, and from these response spectrum curves the spectrum intensities have been determined. From these spectrum intensities certain conclusions are drawn as to: (1) the effects of local geology on the recorded ground motions; (2) the calculation of total energy released by the earthquake from strong-motion accelerometer records; (3) possible influence of structural dynamic behavior on the accelerations recorded in building basements, and the relationship between basement accelerations and ground accelerations; and (4) the applicability of a simplified type of strong-motion earthquake instrument for investigations of local distribution effects. A general comparison is made between the present earthquake and typical Pacific Coast earthquakes.

scholarly journals A Time-Based Objective Measure of Exposure to the Food Environment

2019 ◽  
Vol 16 (7) ◽  
pp. 1180 ◽  
Author(s):  
Jason Scully ◽  
Anne Moudon ◽  
Philip Hurvitz ◽  
Anju Aggarwal ◽  
Adam Drewnowski
Keyword(s):  
Food Environment ◽  
Fast Food ◽  
Objective Measure ◽  
Mobility Patterns ◽  
Time Duration ◽  
Positioning Systems ◽  
Global Positioning ◽  
Fast Food Restaurants ◽  
Logistic Regressions ◽  
The Relationship

Exposure to food environments has mainly been limited to counting food outlets near participants’ homes. This study considers food environment exposures in time and space using global positioning systems (GPS) records and fast food restaurants (FFRs) as the environment of interest. Data came from 412 participants (median participant age of 45) in the Seattle Obesity Study II who completed a survey, wore GPS receivers, and filled out travel logs for seven days. FFR locations were obtained from Public Health Seattle King County and geocoded. Exposure was conceptualized as contact between stressors (FFRs) and receptors (participants’ mobility records from GPS data) using four proximities: 21 m, 100 m, 500 m, and ½ mile. Measures included count of proximal FFRs, time duration in proximity to ≥1 FFR, and time duration in proximity to FFRs weighted by FFR counts. Self-reported exposures (FFR visits) were excluded from these measures. Logistic regressions tested associations between one or more reported FFR visits and the three exposure measures at the four proximities. Time spent in proximity to an FFR was associated with significantly higher odds of FFR visits at all proximities. Weighted duration also showed positive associations with FFR visits at 21-m and 100-m proximities. FFR counts were not associated with FFR visits. Duration of exposure helps measure the relationship between the food environment, mobility patterns, and health behaviors. The stronger associations between exposure and outcome found at closer proximities (<100 m) need further research.

scholarly journals Linearity extensions of the market model: a case of the top 10 cryptocurrency prices during the pre-COVID-19 and COVID-19 periods

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Serdar Neslihanoglu
Keyword(s):  
State Space Model ◽  
Additive Model ◽  
Market Model ◽  
Time Varying ◽  
Daily Data ◽  
Forecasting Performance ◽  
Modeling And Forecasting ◽  
Crypto Currency ◽  
Beta Risk ◽  
The Relationship

AbstractThis research investigates the appropriateness of the linear specification of the market model for modeling and forecasting the cryptocurrency prices during the pre-COVID-19 and COVID-19 periods. Two extensions are offered to compare the performance of the linear specification of the market model (LMM), which allows for the measurement of the cryptocurrency price beta risk. The first is the generalized additive model, which permits flexibility in the rigid shape of the linearity of the LMM. The second is the time-varying linearity specification of the LMM (Tv-LMM), which is based on the state space model form via the Kalman filter, allowing for the measurement of the time-varying beta risk of the cryptocurrency price. The analysis is performed using daily data from both time periods on the top 10 cryptocurrencies by adjusted market capitalization, using the Crypto Currency Index 30 (CCI30) as a market proxy and 1-day and 7-day forward predictions. Such a comparison of cryptocurrency prices has yet to be undertaken in the literature. The empirical findings favor the Tv-LMM, which outperforms the others in terms of modeling and forecasting performance. This result suggests that the relationship between each cryptocurrency price and the CCI30 index should be locally instead of globally linear, especially during the COVID-19 period.

scholarly journals The relationship between body image and emotional and cognitive impairment after brain damage: A preliminary study

2021 ◽  
Author(s):  
Francesco Corallo ◽  
Dominique Tarda ◽  
Valentina Coppola ◽  
Lilla Bonanno ◽  
Viviana Lo Buono ◽  
...  
Keyword(s):  
Body Image ◽  
Cognitive Impairment ◽  
Brain Damage ◽  
Preliminary Study ◽  
The Relationship

scholarly journals The Relation between Physiological Parameters and Colour Modifications in Text Background and Overlay during Reading in Children with and without Dyslexia

2021 ◽  
Vol 11 (5) ◽  
pp. 539
Author(s):  
Tamara Jakovljević ◽  
Milica M. Janković ◽  
Andrej M. Savić ◽  
Ivan Soldatović ◽  
Gordana Čolić ◽  
...  
Keyword(s):  
Fixation Duration ◽  
Physiological Parameters ◽  
School Age Children ◽  
Control Group ◽  
School Age ◽  
Time Duration ◽  
The Relationship ◽  
White Colour ◽  
Saccade Duration ◽  
40 Hz

Reading is one of the essential processes during the maturation of an individual. It is estimated that 5–10% of school-age children are affected by dyslexia, the reading disorder characterised by difficulties in the accuracy or fluency of word recognition. There are many studies which have reported that coloured overlays and background could improve the reading process, especially in children with reading disorders. As dyslexia has neurobiological origins, the aim of the present research was to understand the relationship between physiological parameters and colour modifications in the text and background during reading in children with and without dyslexia. We have measured differences in electroencephalography (EEG), heart rate variability (HRV), electrodermal activities (EDA) and eye movements of the 36 school-age (from 8 to 12 years old) children (18 with dyslexia and 18 of control group) during the reading task in 13 combinations of background and overlay colours. Our findings showed that the dyslexic children have longer reading duration, fixation count, fixation duration average, fixation duration total, and longer saccade count, saccade duration total, and saccade duration average while reading on white and coloured background/overlay. It was found that the turquoise background, turquoise overlay, and yellow background colours are beneficial for dyslexic readers, as they achieved the shortest time duration of the reading tasks when these colours were used. Additionally, dyslexic children have higher values of beta (15–40 Hz) and the broadband EEG (0.5–40 Hz) power while reading in one particular colour (purple), as well as increasing theta range power while reading with the purple overlay. We have observed no significant differences between HRV parameters on white colour, except for single colours (purple, turquoise overlay, and yellow overlay) where the control group showed higher values for mean HR, while dyslexic children scored higher with mean RR. Regarding EDA measure, we found systematically lower values in children with dyslexia in comparison to the control group. Based on the present results, we can conclude that both pastel and intense background/overlays are beneficial for reading of both groups and all sensor modalities could be used to better understand the neurophysiological origins in dyslexic children.

scholarly journals Caring for Things Helps Humans Grow: Effects of Courteous Interaction with Things on Pro-Environmental Behavior

2021 ◽  
Vol 13 (7) ◽  
pp. 3969
Author(s):  
Hiroko Kamide ◽  
Tatsuo Arai
Keyword(s):  
Environmental Behavior ◽  
Well Being ◽  
Environmentally Conscious ◽  
Everyday Objects ◽  
Preliminary Study ◽  
The Relationship ◽  
Active Care ◽  
Familiar Objects

The purpose of this study was to clarify the influence of courteous interaction with familiar objects on pro-environmental behavior and well-being. We explored the process of interaction with everyday objects, such as pens and glasses in a preliminary study (N = 64), and to reveal two aspects that define these interactions, namely active care for objects and awareness of learning from the interaction (N = 687; Study 1). The more people cared for and learned through their interactions with a particular object, the more they perceived a connectedness to it (N = 195; Study 2). Furthermore, caring for and learning with familiar objects promoted various environmentally conscious behaviors and contributed to individual well-being (Study 3; N = 600). In this way, we discussed the relationship between interaction with everyday objects, the aspects of these interactions, and the influence of these interactions on an individual’s perspective toward the wider environment.

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