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This paper aims to investigate with strain-rate controlled uniaxial cyclic compression tests the softening behavior of concrete and its elastic stiffness degradation with increasing plastic straining.

Such tests at ambient temperature show that concrete exhibits the phenomenon of elastic stiffness degradation, which can be captured by damage-plasticity models.

The experimentally derived evolutions of the elastic stiffness with plastic strain confirm the suitability of the damage-plasticity modeling concept for concrete in compression at elevated temperatures and provide novel calibration data.

Temperature-dependent concrete models implementing this modeling concept are often used presently in structural fire engineering, despite the lack of experiment-based validation data.

The cross-sectional capacity of steel sections subjected to fire is strongly affected by the decreasing stiffness during heating and the nonlinear stress-strain relationship of steel at elevated temperatures. This paper analyses the cross-sectional capacity of common steel sections subjected to combined axial compression and biaxial bending moments at both ambient and elevated temperatures considering section yielding and local buckling effects. The results of a parametric study using the finite element approach are presented as temperature-dependent normalized N-M interaction curves and are compared to results using elastic and plastic interaction formulae. A comparative study shows that European fire design models may lead to conservative results for semi-compact and slender cross sections (class 3 and 4 sections) due to the partial plastic capacity of these sections. However, for steel members predominately subjected to axial compression the design models may lead to unconservative results due to local buckling deflections that occur even for plastic and compact sections (class 1 and 2).

In this study, engineering stress-strain relationships considering an effect of strain rate on steel materials at elevated temperatures were formulated and a simplified analytical model using a two-dimensional beam element to analytically examine the effect of strain rate on the load-bearing capacity and collapse temperature was proposed.

The stress-strain relationships taking into account temperature, strain, and strain rate were established based on the past coupon test results with strain rate as the test parameter. Furthermore, an elasto-plastic analysis using a two-dimensional beam element, which considered the effect on strain rate, was conducted for both transient- and steady-state conditions.

The analytical results agreed relatively well with the test results, which used small steel beam specimens with a rectangular cross-section under various heating rates (transient-state condition) and deformation rates (steady-state condition). It was found that the bending strength and collapse temperature obtained from the parametric analyses agreed relatively well with those evaluated using the effective strength obtained from the coupon tests with strain equal to 0.01 or 0.02 under the fast strain rates.

The effect of stress degradation, including the stress-strain relationships at elevated temperature, was mitigated by considering the effect of strain rate on the analytical model. This is an important point to consider when considering the effect of strain rate on steel structural analysis at elevated temperatures to maintain analytical stability unaccompanied by the stress degradation.

The purpose of the study is to propose a framework for understanding the dynamism of the human self-system from evolutionary and socio-psychological perspective. The study aims to help scholars interested to use an evolutionary lens for examining consumer behaviour.

Relying on the principle of self-cybernetics, the study proposed a general framework explaining the operating mechanism of human self-system. The proposed framework incorporates the socio-psychological and the evolutionary perspective of the human self-concept.

The framework may help consumer scholars to integrate socio-psychological and evolutionary theories to produce novel and testable hypotheses.

To the best of the authors’ knowledge, this is the first attempt to propose a framework based on the principle of cybernetics to facilitate the use of an evolutionary lens in consumer research.

The purpose of this paper is to elaborate on how people navigate the social media ecosystem and how they decide, which social network site (SNS) to use. To this end, the current study draws from uses and gratifications (U&G) theory to elicit and compare motives for the use of Facebook and Twitter and uses behavioral data to examine the findings in the context of technology non-use.

An online survey was administered to 232 Facebook users and the results were complemented with 12 usage variables collected via the Facebook application programing interface for the same users. Exploratory factor analysis identified and described the motives for using Facebook and Twitter and multiple regression models examined the relationships between the motives for using the two sites. A multivariate analysis of variance and a series of t-tests investigated the differences in actual behavior between Twitter users and non-users.

Results suggest that SNS users will use both sites to gratify their need for information, but will only do so for entertainment that has social characteristics. Furthermore, Facebook users that are more embedded in the site and use the site to support their offline life are more likely to also use Twitter.

The paper includes implications for SNS researchers, designers and managers by highlighting the motivational and behavioral differences between users of the two sites and the importance of technological affordances for understanding and explaining SNS selection.

This study extends previous cross-site U&G and non-use research by combining survey and behavioral data.

This study aims to explore whether gratification matters in influencing consumers' attitudes towards purchase in the context of livestream shopping and the antecedents that lead to consumers' gratification perceptions.

Four technology affordances (i.e. modality affordance, agency affordance, interactivity affordance and navigability affordance) and two gratifications (information gratification and entertainment gratification) are identified, and the relationships among the technology affordances, gratifications and purchase intention are examined. The model is tested using structural equation modeling.

The result shows that both information and entertainment gratification are positively associated with consumer purchase intention. No significant results have been uncovered with the relationship between interactivity affordance and entertainment gratification, while the rest relationships of gratification and its antecedents are positively associated.

The findings of this study uncover the antecedents and consequences of gratification in the context of livestreaming from technology affordance perspective. The uncovered relationships among technology affordance, gratification, purchase intention as well as the moderation roles aroused by price consciousness contribute to the extant literature.

The purpose of this paper is to understand consumers’ preferences for answers about sexually transmitted diseases on social question and answer (Q&A) sites by employing message features and information sources as conceptual frameworks.

The study compared best answers selected by questioners with their randomly drawn counterpart non-best answers on Yahoo! Answers as a paired sample (n=180).

The findings indicate that questioners on social Q&A sites were more likely to prefer answers including message features such as numeric information, social norms, optimistic information, and loss-framing, as well as information sources that featured expertise, references, and links to other websites. Pessimistic information was negatively associated with questioners’ preference for answers.

The study extended the discussion of consumers’ selection of best answers to message features and information sources as additional criteria.

The findings suggest that answerers on social Q&A sites communicate more effectively with their audiences by utilizing persuasive communication.

There is a quality issue on social Q&A sites. The findings will be helpful for health professionals to develop answers that are more likely to be selected as best answers, which will enhance overall quality of health information on social Q&A sites.

Consumers’ preference criteria for health information have been investigated using many different approaches. However, no study has used a persuasion framework to examine how consumers appraise answer quality. The present study confirmed consumers’ preference criteria as found in previous social Q&A studies and extended the discussion of consumers’ perceptions of answer quality by applying the frameworks of message features and information sources.