235 research outputs found
Effect of Instantaneous Load Eccentricities on the Inelastic Torsional Responses Under Bi-Directional Seismic Excitations
This study evaluated the inelastic torsional response due to instantaneous load eccentricities. The load eccentricities, which caused by the motion of the center of mass are time-dependent, even exist for two-way symmetric structures under seismic excitations. The eccentricities and bi-directional horizontal excitations can lead to the torsional motion. The study of the impacts of such a second-order effect (called A-Delta effect) on structural systems and, this effect in combination with the P-Delta effect on structural systems has not been reported in the literature.
This study is focused on the investigation of the structural responses under the A-Delta and/or P-Delta effects. For the assessment of inelastic seismic displacement demand and inelastic torsional response of buildings, the structure is represented using idealized one-story model and each lateral load resisting element is modeled using the Bouc-Wen hysteretic model. The governing equations of motion were developed by considering these effects and the structures that are subjected to biaxial excitations. The numerical analyses were carried out by implementing the governing equations in MATLAB. Since the ground motion is uncertain and varies from record-to-record, 123 ground motion records from 11 California seismic events were considered to take into account this record-to-record variability.
The results indicate that a slight underestimation of seismic displacement demand is observed, if the instantaneous load eccentricities are ignored, especially for two-way symmetrical systems. On the other hand, when considering both the instantaneous load eccentricities and P-Delta effect, the instantaneous load eccentricities can introduce significant changes on both lateral and torsional displacements, if the stability factor is large
Interleukin-17A promotes functional activation of systemic sclerosis patient-derived dermal vascular smooth muscle cells by extracellular-regulated protein kinases signalling pathway
How Social Support Motivates Trust and Purchase Intentions in Mobile Social Commerce
Purpose ā This study refers to the social support and trust theories to explore what kind of factors affect the usersā intention to adopt MSC.
Design/methodology/approach ā A total of 207 subjects who had previously experienced or known about MSC were identified and partial least squares were performed to analyse the measurement and structural models.
Findings ā The results indicated that MSC purchase intentions are affected significantly by four other factors (social support, perceived usefulness, subjective norm, and trust) and trust, in turn, is affected
by three factors (social support, perceived usefulness, and subjective norms).
Originality/value ā First, this study examines the mechanism of trust formation and actions in the MSC context. Second, this study contributes by confirming the important role of social factors in the MSC context. Third, the study expands the social support theory.
Finally, our research provides empirical evidence for enterprises that have adopted MSC to support their marketing strategy and programmes
Direct Signal Detection Without DataāAided: A MIMO Functional Network Approach
Functional network (FN) has been successfully applied in many fields, but so far no methods of direct signal detection (DSD) using FN have been published. In this chapter, a novel DSD approach using FN, which can be applied to cases with a plural source signal sequence, with short sequence, and even with the absence of a training sequence, is presented. Firstly, a multipleāinput multipleāoutput FN (MIMOFN), in which the initial input vector is devised via QR decomposition of the receiving signal matrix, is constructed to solve the special issues of DSD. In the meantime, the design method for the neural function of this special MIMOFN is proposed. Then the learning rule for the parameters of neural functions is trained and updated by backāpropagation (BP) algorithm. The correctness and effectiveness of the new approach are verified by simulation results, together with some special simulation phenomena of the algorithm. The proposed method can detect the source sequence directly from the observed output data by utilizing MIMOFN without a training sequence and estimating the channel impulse response
Association Between Different Indicators of Obesity and Depression in Adults in Qingdao, China: A Cross-Sectional Study
Background: This study was designed to investigate the perceived relationship between body weight and depression risk in a Chinese population in Qingdao, China.Methods: A population-based cross-sectional survey was performed with 4,573 participants (between 35 and 74 years) from the year 2009 to 2012 in Qingdao, China. We applied the Zung self-rating depression scale to ascertain the level of depression in participants. The associations between different indicators of obesity [body mass index (BMI), waist circumference (WC), and waist-to-hip ratio (WHR)] and depression were assessed by logistic regression based on the Chinese criteria of obesity. Sensitivity analysis was done based on the Asian and WHO criteria of obesity.Results: The Zung scores for the 243 participants (5.2%) were over 45 and they were entitled as depression. Furthermore, multivariable logistic analyses revealed that being overweight [odds ratios (OR): 1.48, 95% confidence intervals [95% CI]: 1.08ā2.03] and having abdominal obesity (WC category in Chinese criteria) (OR: 1.47, 95% CI: 1.08-2.00) were often associated with a higher risk for depression compared to normal weight subjects. Sensitivity analysis revealed that abdominal obesity (Asian criterion) (OR: 1.41, 95% CI: 1.03-1.91) was a significant risk factor for depression. Similarly, being overweight (WHO criterion) (OR: 1.39, 95% CI: 1.03-1.87) was an obvious risk factor for depression.Conclusion: Being overweight and having abdominal obesity (WC category) were found to be linked with a higher risk of depression. However, abdominal obesity (WHR category) was not associated with depression
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