Behavior of oil-based modeling clay at medium strain rates

The modeling clay is an oil-based soft, flowable, and pliable material made from waxes and oils. Besides its primary use for making sculptures, the modeling clay is commonly used to evaluate bulletproof vests and simulate metal manufacturing processes by conformation. In ballistic tests, the clay is used to retain the deformation of the rear face of body armors; and in the study of metal forming processes, it is used as a physical model to provide information on the plastic flow. However, its mechanical dynamic behavior is not entirely understood. In this study, Plastilina Roma No. 1 modeling clay was mechanically characterized using the power-law constitutive model at medium strain rates [Formula: see text]. The material parameters were determined using a penetration model based on the Cavity Expansion Theory and an inverse technique involving the comparison of the model with experimentation. The optimum set of constitutive parameters was found by reducing the difference of the calculated penetration profile and the measurements from a drop test. This optimization process was programmed on the MATLAB–Simulink environment. The determined material parameters were validated by comparing the results from a computational model with three test set-ups. Finite element model results show good concordance with experimental measurements.

The Pedagogy of Vulnerability and Marketing Education: Cultivating Self-expansion in a Time of Separation

Applying the pedagogy of vulnerability and self-expansion theory, the exercise known as the Know Me Activity (KMA) enhances self-expansion by encouraging connections between students and the instructor. The pedagogy of vulnerability is premised on risking self-disclosure as an act of courage. Self-expansion theory is grounded in personal relationships whereby individuals are motivated for personal growth and identify with others to gain access to their resources. In the context of marketing education, self-expansion stems from enhancing student self-awareness for personal growth as well as perceived vulnerability and relatedness of the instructor to encourage access to expertise. The KMA was conducted at three universities and assessed to determine its usefulness as a self-expansion exercise. Survey results indicate that students found the activity contained self-expansion characteristics, and they recommend it for future use. The results of the pretest and posttest analyses also demonstrated an increase in student self-awareness, perceived instructor vulnerability, and perceived instructor relatedness. Self-expansion activities enhance relationships by design and participating in them can lead to increased student effort and persistence. Marketing educators can, therefore, have confidence in utilizing the KMA as a means for mitigating social isolation and encouraging perseverance.

Digital Marketing Effects of Clubhouse on Crowdfunding in the Context of COVID-19

In the marketing mix, promotion is mentioned as using the communication channels available to present and market the product or service at hand. In recent years, social media has risen as an influential marketing communication channel in digital space. Apart from end-to-end direct messengers and video communication in times of the COVID-19 pandemic, the social media channel Clubhouse offers an audio-only experience. The current research lacks analysis of the potential influence of the hyped social network. Due to the novelty of the channel and the absence of text messages as well as visual stimuli, questions regarding the impact that usage of this social media channel might have on crowdfunding, a means of rising popularity in alternative financing, have arisen. The study builds upon the media richness theory of Daft and Lengel as well as the channel expansion theory of Carlson and Zmud. Besides literature research, explorative expert interview analyses were applied to answer the research question at hand. The main findings include different approaches to foster the opportunities of Clubhouse for marketing crowdfunding campaigns in line with insights about the user group of Clubhouse as well as development options for the platform.

Chaotic Dynamics of Partial Difference Equations with Polynomial Maps

In this paper, chaotic dynamics of a class of partial difference equations are investigated. With the help of the coupled-expansion theory of general discrete dynamical systems, two chaotification schemes for partial difference equations with polynomial maps are established. These controlled equations are proved to be chaotic either in the sense of Li–Yorke or in the sense of both Li–Yorke and Devaney. One example is provided to illustrate the theoretical results with computer simulations for demonstration.