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This paper describes the diffraction of the lowest plane wave propagating out of the opening of a semi-infinite hard duct that is symmetrically placed inside an infinite soft duct. The whole system forms a pentafurcated waveguide whose solution is given by eigenfunction expansion. The same method has been used to validate the results of a trifurcated duct problem previously tackled by using the standard Wiener-Hopf technique. Some graphical results showing the influence of waveguide spacing on the reflection coefficient are presented. We compared our results with the related existing work. We observe that the accumulative value of reflection for current pentafurcated duct is 1375.1, which is the greatest among the related trifurcated and existing pentafurcated ducts. Hence the soft lining on outer plates gives better results to attenuate the unwanted noise. These problems have application in acoustics. Key words: exhaust system, eigenfunction expansion, diffraction, tri- and pentafurcated ducts, soft and rigid plates. Nous decrivons dans ce papier la diffraction de la plus basse onde plane sortant d'un conduit rigide semi-infini qui est symetriquement insere dans un conduit ductile infini. L'ensemble de ce systeme forme un guide d'onde penta-ramifie dont la solution est donnee par une methode d'expansion en fonctions propres. Cette methode est utilisee afin de valider les resultats pour un conduit tri-ramifie, precedemment etudie a l'aide de la technique standard de Wiener-Hopf. A l'aide d'une presentation graphique, nous montrons l'influence de l'espacement des conduits sur le coefficient de reflexion. Nous comparons nos resultats avec les resultats du meme type dans la litterature. Nous observons que la valeur cumulee du coefficient de reflexion pour notre conduit penta-ramifie courant est 1375.1, ce qui represente la plus grande valeur parmi les conduits tri-ramifies relies et penta-ramifies existants. Ainsi la garniture ductile sur les plaques exterieures permet les meilleurs resultats pour attenuer le bruit non desire. Ces problemes trouvent des applications interessantes en acoustique. [Traduit par la Redaction] Mots-cles: conduit de sortie, expansion en fonctions propres, diffraction, tri- et penta-ramifie, plaques souples et rigides., 1. Introduction Noise is a serious current issue and a hazard to environmental health [1]. Machines running with high sound intensity produce noise through air ducts, which act as waveguides [...]

A vehicular ad hoc network (VANET) is a technique that uses vehicles with the ability to sense data from the environment and use it for their safety measures. Flooding is a commonly used term used for sending network packets. VANET may cause redundancy, delay, collision, and the incorrect receipt of the messages to their destination. Weather information is one of the most important types of information used for network control and provides an enhanced version of the network simulation environments. The network traffic delay and packet losses are the main problems identified inside the network. In this research, we propose a routing protocol which can transmit the weather forecasting information on demand based on source vehicle to destination vehicles, with the minimum number of hop counts, and provide significant control over network performance parameters. We propose a BBSF-based routing approach. The proposed technique effectively enhances the routing information and provides the secure and reliable service delivery of the network performance. The results taken from the network are based on hop count, network latency, network overhead, and packet delivery ratio. The results effectively show that the proposed technique is reliable in reducing the network latency, and that the hop count is minimized when transferring the weather information. [ABSTRACT FROM AUTHOR]

With the rapid advancement in THz technology and continuously increasing number of electrical and electronic devices in this frequency band, highly efficient and functional THz shielding materials are required to ensure the intended working of these devices. Polymeric composites of hybrid nano-fillers including CNFs and magnetic nanoparticles possess distinctive capability of providing high shielding efficiency primarily absorptive in nature with field functional properties. In this article, lightweight polymeric nanocomposite coatings of continuous carbon nanofibers and magnetite (Fe3O4), as potential shielding material for the THz frequency band, have been prepared using a cost-effective conventional air-spray coating method. The obtained results are quite exclusive, as the sample with 40 wt % Fe3O4 outperforms at a very low thickness value of 540 μm, showing the highest SE value of ∼60 dB. These results are superior compared to the results obtained from most of the contemporary polymer composite materials, which usually provide good shielding at high thickness values in the mm range. Also, this study establishes that shielding performance of the polymeric hybrid nanocomposites (Fe3O4 + CNFs) is substantially better than a single nanocomposite CNF filler previously synthesized and characterized through the same approach. [ABSTRACT FROM AUTHOR]

Depression is a mental psychological disorder that may cause a physical disorder or lead to death. It is highly impactful on the socialeconomical life of a person; therefore, its effective and timely detection is needful. Despite speech and gait, facial expressions have valuable clues to depression. This study proposes a depression detection system based on facial expression analysis. Facial features have been used for depression detection using Support Vector Machine (SVM) and Convolutional Neural Network (CNN). We extracted micro-expressions using Facial Action Coding System (FACS) as Action Units (AUs) correlated with the sad, disgust, and contempt features for depression detection. A CNN-based model is also proposed in this study to auto classify depressed subjects from images or videos in real-time. Experiments have been performed on the dataset obtained from Bahawal Victoria Hospital, Bahawalpur, Pakistan, as per the patient health questionnaire depression scale (PHQ-8); for inferring the mental condition of a patient. The experiments revealed 99.9% validation accuracy on the proposed CNN model, while extracted features obtained 100% accuracy on SVM. Moreover, the results proved the superiority of the reported approach over state-of-the-art methods. [ABSTRACT FROM AUTHOR]