3D face detection based on salient features extraction and skin colour detection using data mining

Face detection has an essential role in many applications. In this paper, we propose an efficient and robust method for face detection on a 3D point cloud represented by a weighted graph. This method classifies graph vertices as skin and non-skin regions based on a data mining predictive model. Then, the saliency degree of vertices is computed to identify the possible candidate face features. Finally, the matching between non-skin regions representing eyes, mouth and eyebrows and salient regions is done by detecting collisions between polytopes, representing these two regions. This method extracts faces from situations where pose variation and change of expressions can be found. The robustness is showed through different experimental results. Moreover, we study the stability of our method according to noise. Furthermore, we show that our method deals with 2D images.     

Benzimidazole and Benzoxazole Zinc Chelators as Inhibitors of Metallo-β-Lactamase NDM-1

Bacterial expression of β-lactamases, which hydrolyze β-lactam antibiotics, contributes to the growing threat of antibacterial drug resistance. Metallo-β-lactamases, such as NDM-1, use catalytic zinc ions in their active sites and hydrolyze nearly all clinically available β-lactam antibiotics. Inhibitors of metallo-β-lactamases are urgently needed to overcome this resistance mechanism. Zinc-binding compounds are promising leads for inhibitor development, as many NDM-1 inhibitors contain zinc-binding pharmacophores. Here, we evaluated 13 chelating agents containing benzimidazole and benzoxazole scaffolds as NDM-1 inhibitors. Six of the compounds showed potent inhibitory activity with IC₅₀ values as low as 0.38 μM, and several compounds restored the meropenem susceptibility of NDM-1-expressing E. coli. Spectroscopic and docking studies suggest ternary complex formation as the mechanism of inhibition, making these compounds promising for development as NDM-1 inhibitors.     

Energy harvesting: State-of-the-art

This paper presents a brief history of energy harvesting for low-power systems followed by a review of the state-of-the-art of energy harvesting techniques, power conversion, power management, and battery charging. The advances in energy harvesting from vibration, thermal, and RF sources are reviewed as well as power management techniques. Examples of discrete form implementation and integrated form implementation using microelectromechanical systems (MEMS) and CMOS microelectronic processes are also given. The comparison between the reviewed works concludes this paper.     

High-Rate Printing of Micro/Nanoscale Patterns Using Interfacial Convective Assembly

Printing of electronics has been receiving increasing attention from academia and industry over the recent years. However, commonly used printing techniques have limited resolution of micro- or sub-microscale. Here, a directed-assembly-based printing technique, interfacial convective assembly, is reported, which utilizes a substrate-heating-induced solutal Marangoni convective flow to drive particles toward patterned substrates and then uses van der Waals interactions as well as geometrical confinement to trap the particles in the pattern areas. The influence of various assembly parameters including type of mixing solvent, substrate temperature, particle concentration, and assembly time is investigated. The results show successful assembly of various nanoparticles in patterns of different shapes with a high resolution down to 25 nm. In addition, the assembly only takes a few minutes, which is two orders of magnitude faster than conventional convective assembly. Small-sized (diameter below 5 nm) nanoparticles tend to coalesce during the assembly process and form sintered structures. The fabricated silver nanorods show single-crystal structure with a low resistivity of 8.58 × 10⁻⁵ Ω cm. With high versatility, high resolution, and high throughput, the interfacial convective assembly opens remarkable opportunities for printing next generation nanoelectronics and sensors.     

Experimental Investigation of Heat Transfer Enhancement in a Two-Pass Square Duct by Permeable Ribs

This investigation presents the heat transfer enhancement results of flow past repeated permeable ribs mounted on the bottom surface of a two-pass square channel. Spatially periodic flow interruption generated by rib arrays mounted on the walls is extensively used for augmentation of heat transfer in turbine blade cooling passages. To remove the local heat transfer deterioration in the vicinity region of the solid ribs, permeable ribs have been proposed in the literature for single pass coolant passages. This study intends to investigate the performance of permeable ribs array placed on the lower wall of a two-pass channel compared to that of the solid rib array. The heat transfer and friction characteristics are investigated for smooth, solid-ribbed, slit-ribbed, and split-slit-ribbed square channels for the Reynolds numbers of 5,500, 12,800, and 16,400. An array of ribs (consisting of fifteen ribs) has been mounted over the total test section, with seven each in the first and second passes, and one in the bend. The performance analysis has been carried out using thermal performance on the basis of constant pumping power and entropy generation principle.     

Phosphonated graphene oxide with high electrocatalytic performance for vanadium redox flow battery

Development of more efficient electrodes is essential to improve the competitiveness of vanadium redox flow battery (VRFB) systems. Covalent functionalization of carbon structure in graphene oxide with phosphonic acid groups was carried out to enhance the electrode wettability. The phosphonated graphene oxide (P-GO) was characterized and found displaying an improved electrocatalytic performance towards electrooxidation/electroreduction of vanadium ion pairs. The defect in P-GO structure increased the negative charge density on the surface leading to higher vanadium ions tendency for electrooxidation/electroreduction reactions. The battery performance was evaluated using electrodes made of carbon felt hosted GO and P-GO in a single cell VRFB and 180 charge-discharge cycles were recorded. The VRFB with P-GO displayed an improved performance and stable coulombic, voltage and energy efficiency compared to VRFB with GO.