Hopf cyclic cohomology in braided monoidal categories

We extend the formalism of Hopf cyclic cohomology to the context of braided categories. For a Hopf algebra in a braided monoidal abelian category we introduce the notion of stable anti-Yetter-Drinfeld module. We associate a para-cocyclic and a cocyclic object to a braided Hopf algebra endowed with a braided modular pair in involution in the sense of Connes and Moscovici. When the braiding is symmetric the full formalism of Hopf cyclic cohomology with coefficients can be extended to our categorical setting.Comment: 50 pages. One reference added. Proofs are visualized through braiding diagrams. Final version to appear in `Homology, Homotopy and Applications

Employing Antenna Selection to Improve Energy-Efficiency in Massive MIMO Systems

Massive MIMO systems promise high data rates by employing large number of antennas, which also increases the power usage of the system as a consequence. This creates an optimization problem which specifies how many antennas the system should employ in order to operate with maximal energy efficiency. Our main goal is to consider a base station with a fixed number of antennas, such that the system can operate with a smaller subset of antennas according to the number of active user terminals, which may vary over time. Thus, in this paper we propose an antenna selection algorithm which selects the best antennas according to the better channel conditions with respect to the users, aiming at improving the overall energy efficiency. Then, due to the complexity of the mathematical formulation, a tight approximation for the consumed power is presented, using the Wishart theorem, and it is used to find a deterministic formulation for the energy efficiency. Simulation results show that the approximation is quite tight and that there is significant improvement in terms of energy efficiency when antenna selection is employed.Comment: To appear in Transactions on Emerging Telecommunications Technologies, 12 pages, 8 figures, 2 table

Automated segmentation and morphological characterization of placental histology images based on a single labeled image

In this study, a novel method of data augmentation has been presented for the segmentation of placental histological images when the labeled data are scarce. This method generates new realizations of the placenta intervillous morphology while maintaining the general textures and orientations. As a result, a diversified artificial dataset of images is generated that can be used for training deep learning segmentation models. We have observed that on average the presented method of data augmentation led to a 42% decrease in the binary cross-entropy loss of the validation dataset compared to the common approach in the literature. Additionally, the morphology of the intervillous space is studied under the effect of the proposed image reconstruction technique, and the diversity of the artificially generated population is quantified. Due to the high resemblance of the generated images to the real ones, the applications of the proposed method may not be limited to placental histological images, and it is recommended that other types of tissues be investigated in future studies

The Effect of Long Service Life on the Accuracy of Dentaport ZX Electronic Apex Locator

Introduction: Electronic apex locators are among the most acceptable instruments for determining root canal length. The present study aimed to evaluate the effect of long service life on the accuracy of the Dentaport Root ZX (DP ZX) electronic apex locator (EAL). Materials and Methods: In this study, fifty single-rooted freshly extracted human teeth were used. After determining the root canal length with a K-file and a dental operative microscope, the canals were measured with four separate DP ZX apex locators (two with more than 6 years of life service while two others had less than 6 years of life service). Data were analyzed by repeated ANOVA measurement. Results: No significant difference was found between the EALs with different years of life services (P=0.62). All EALs could determine root canal length with high accuracy of more than 94%. Conclusion: Based on the results of this in vitro study, the long service life had no significant impact on the accuracy of DP ZX EALs in terms of root canal length determination

Modelling crack propagation in RC beam-column joints

Accurate modelling is required to estimate crack propagation in a beam–column joint. In this study, a numerical method is developed to model crack propagation and failure loading in a beam–column joint under static load. To realize this objective, a four-node, thin-layer interface element is produced to model the fracture process zone and crack propagation. Moreover, the fracture criterion for determining the growth of a crack based on the release rate of strain energy is established. To validate the present model, ABAQUS software is used to simulate crack propagation by conventional cohesive elements. The numerical results obtained are extremely close to the experimental results within an accuracy level ranging from 4.3% to 6.7%. Meanwhile, the ABAQUS software data and the experimental data are predicted at a margin of error ranging from 12.4% to 16%