We illustrate the importance of geometrically accurate volume quadrature for obtaining optimal accuracy with non-boundary-fitted finite element discretizations, when the problem domain is defined by sharp boundaries. We consider the tetrahedral finite cell method (TetFCM) and replace its recursive subdivision based integration approach with geometrically accurate quadrature rules that emanate from higher-order geometric parametrizations of cut tetrahedral elements. The elementwise parametrization procedure relies on the identification of the intersection topology and a series of higher-order mappings based on Lagrange polynomials. We demonstrate with several 3D examples that geometrically faithful local parametrization ensures optimal accuracy, while significantly reducing the number of quadrature points with respect to recursive subdivision. On the other hand, we highlight the strength of subdivision quadrature in the context of a patient-specific workflow for the simulation-based performance analysis of coupled bone/implant configurations. In particular, we show that accuracy, flexibility and computational efficiency of the TetFCM critically depends on flexibly applying the two different quadrature variants for fuzzy imaging data and sharp boundary representations, respectively.

Bed and Breakfast innkeeping as a form of self-employment is often perceived by aspiring innkeepers as a lifestyle choice that seemingly integrates work and lifeand enhances personal well-being. On the other hand, innkeeping as a business is known for long work hours and limited escape from work due to the blurred physical and temporal boundaries between work and life. Given the paradox, this exploratory study examined the respite experience (an interval of rest and relief from work) of innkeepers and its effect on subjective well-being. The findings from an online survey among 327 innkeepers in the United States reveal that innkeepers lack short-term respites at regular intervals. Engagement in active and high-effort social or hobby-based respite activities is found to be a primary pathway to an effective respite experience in the absence of psychological detachment from work. The results show that respite experience has a significant effect on an innkeeper's subjective well-being after controlling for job demands, entrepreneurial motivation, and financial performance of the inn. This research has also identified three clusters of innkeepers (lifestyle innkeepers, seasonal innkeepers, and career innkeepers) based on their respite characteristics and other related operational and individual variables.

The prime objective of spectrum sensing in Cognitive Radio (CR) networks is to increase the efficiency of spectrum utilization and improve the network performance. Both of false probability and misdetection probability can reduce the network performance. We use the mean error detection probabilities to denote the network performance. As the value of the mean detection probabilities decreases, the network performance will be improved. In order to achieve this aim, we use the Markov model of the channel occupancy to estimate the prior probabilities for the hypothesis test in dynamic traffic environment. Because of the uncertainty under local detection, the spectrum detection scheme is extended to cooperative sensing among multiple second users. Moreover, we also propose a dynamic decision threshold to optimize the cooperative spectrum detection. The numerical results show that our proposed scheme can further reduce the mean error detection probabilities.

No abstract