Improvement of Synchronous Machine Dynamic Characteristics via Neural Network Based Controllers

This paper presents Simulation and experimental study aimed at investigating the effectiveness of an adaptive artificial neural network stabilizer on enhancing the damping torque of a synchronous generator. For this purpose, a power system comprising a synchronous generator feeding a large power system through a short tie line is considered. The proposed adaptive neuro-control system consists of two multi-layered feed forward neural networks, which work as a plant model identifier and a controller. It generates supplementary control signals to be utilized by conventional controllers. The details of the interfacing circuits, sensors and transducers, which have been designed and built for use in tests, are presented. The synchronous generator is tested to investigate the effect of tuning a Power System Stabilizer (PSS) on its dynamic stability. The obtained simulation and experimental results verify the basic theoretical concepts

The Motion of a Point Vortex in Multiply Connected Polygonal Domains

We study the motion of a single point vortex in simply and multiply connected polygonal domains. In case of multiply connected domains, the polygonal obstacles can be viewed as the cross-sections of 3D polygonal cylinders. First, we utilize conformal mappings to transfer the polygonal domains onto circular domains. Then, we employ the Schottky-Klein prime function to compute the Hamiltonian governing the point vortex motion in circular domains. We compare between the topological structures of the contour lines of the Hamiltonian in symmetric and asymmetric domains. Special attention is paid to the interaction of point vortex trajectories with the polygonal obstacles. In this context, we discuss the effect of symmetry breaking, and obstacle location and shape on the behavior of vortex motion

Wireless technology: current status and future directions

Wireless Technology is expected to be the dominant mode of access technology in the future. Besides voice, a new data range of services such as multimedia and high speed data are being offered for delivery over wireless network. Mobility will be seamless, realizing the concept of persons' being in contact anywhere, at any time. Throughout this paper, we review the long, interesting development of wireless communication in the past, examine the current progress in standards and technologies, and finally discuss possible trends for wireless communication solutions

Mesoscopic open-eye core–shell spheroid carved anode/cathode electrodes for fully reversible and dynamic lithium-ion battery models

We report on the key influence of mesoscopic super-open-eye core–shell spheroids of TiO2- and LiFePO4-wrapped nanocarbon carved anode/cathode electrodes with uniform interior accommodation/storage pockets for the creation of fully reversible and dynamic Li-ion power battery (LIB) models. The mesoscopic core–shell anode/cathode electrodes provide potential half- and full-cell LIB-CR2032 configuration designs, and large-scale pouch models. In these variable mesoscopic LIB models, the broad-free-access and large-open-eye like gate-in-transport surfaces featured electrodes are key factors of built-in LIBs with excellent charge/discharge capacity, energy density performances, and outstanding cycling stability. Mesoscopic open-eye spheroid full-LIB-CR2032 configuration models retain 77.8% of the 1st cycle discharge specific capacity of 168.68 mA h g−1 after multiple cycling (i.e., 1st to 2000th cycles), efficient coulombic performance of approximately 99.6% at 0.1C, and high specific energy density battery of approximately 165.66 W h kg−1 at 0.1C. Furthermore, we have built a dynamic, super-open-mesoeye pouch LIB model using dense packing sets that are technically significant to meet the tradeoff requirements and long-term driving range of electric vehicles (EVs). The full-pouch package LIB models retain a powerful gate-in-transport system for heavy loaded electron/Li+ ion storage, diffusion, and truck movement through open-ended out/in and then up/downward eye circular/curvy folds, thereby leading to substantial durability, and remarkable electrochemical performances even after long-life charge/discharge cycling

Kinetics of Intrahepatic Hepatitis C Virus (HCV)-Specific CD4+ T Cell Responses in HCV and Schistosoma mansoni Coinfection: Relation to Progression of Liver Fibrosis

The kinetics of intrahepatic hepatitis C virus (HCV)-specific CD4+ T cell responses and their role in progression of fibrosis have not previously been characterized. Subjects with HCV/Schistosoma mansoni coinfection have a more rapid progression of HCV liver fibrosis than do those with HCV infection alone. The present prospective longitudinal study compared the liver histology, HCV-specific intrahepatic and peripheral CD4+ T cell proliferative responses, and cytokines (enzyme-linked immunospot) in 48 subjects with unresolved acute HCV infection with or without S. mansoni coinfection, at 6-10 months after acute infection and at the end of follow-up ( months), and the findings were correlated 96±8.7 to the rate of progression of fibrosis per year. Coinfected subjects had significant worsening of fibrosis, compared with subjects with HCV infection alone. At baseline, subjects with HCV infection alone had stronger multispecific intrahepatic HCV-specific CD4+ T helper 1 responses than did coinfected subjects, who had either no responses or weak, narrowly focused responses, and, over time, these T cell responses were maintained only in the liver. The rate of progression of fibrosis and virus load inversely correlated with intrahepatic HCV-specific CD4+ T cell response. The present prospective analysis indicates that enhancement of progression of liver fibrosis is associated with failure to develop early, multispecific, HCV-specific CD4+ Th1 responses, suggesting that novel therapeutic approaches inducing strong cellular immune responses might limit subsequent liver damage in individuals with chronic hepatitis

FABRICATION OF BIOADHESIVE OCUSERT WITH DIFFERENT POLYMERS: ONCE A DAY DOSE

Objective: The objective of this current study is to fabricate ocuserts to control the drug release from chosen bioadhesive polymeric matrixes to enhance patient compliance. Ciprofloxacin HCl (CFX HCl) was selected as a model drug.Methods: Different bioadhesive polymers with different film forming capabilities namely Hydroxy Propyl Methyl Cellulose (HPMC K4M), Poly Vinyl Alcohol (PVA), Sodium Carboxy Methyl Cellulose (Na CMC), Hydroxy Propyl Cellulose (HPC), Sodium Alginate (Na Alg.), pullulan and Xanthan Gum (XG) in different ratios were used in fabricating ocuserts using solvent-casting technique. Propylene Glycol (PG) was used as a plasticizer to facilitate the fabrication process. Characterization tests of the developed ocuserts were performed as well as bioadhesive tests and in vitro release studies of the incorporated drug. The obtained results were analysed using different release kinetic models. Stability of the selected ocuserts was investigated at 40±0.5 °C and 75±5% Relative Humidity (RH) for three months' storage period. In vivo ocular irritation test was performed to investigate the safety of the formula in rabbits' eyes as well as to test the release profile and thus to estimate In vitro In vivo correlation.Results: All the prepared ocuserts showed the uniformity of film characterization and bioadhesion strength ranged from 240±66 and 158±52dyne/cm2. Selected formula from the in vitro release study tested for in vivo study showed the slow release of ciprofloxacin drug up to 24 h with no signs of eye irritancy. Results for In vitro In vivo correlation showed an excellent correlation with R2 value of 0.9982.Conclusion: PVA based ocuserts proven to be a promising once-daily, effective and safe ocular delivery system of the drug

Bootstrapping Conditional GANs for Video Game Level Generation

Generative Adversarial Networks (GANs) have shown im-pressive results for image generation. However, GANs facechallenges in generating contents with certain types of con-straints, such as game levels. Specifically, it is difficult togenerate levels that have aesthetic appeal and are playable atthe same time. Additionally, because training data usually islimited, it is challenging to generate unique levels with cur-rent GANs. In this paper, we propose a new GAN architec-ture namedConditional Embedding Self-Attention Genera-tive Adversarial Network(CESAGAN) and a new bootstrap-ping training procedure. The CESAGAN is a modification ofthe self-attention GAN that incorporates an embedding fea-ture vector input to condition the training of the discriminatorand generator. This allows the network to model non-localdependency between game objects, and to count objects. Ad-ditionally, to reduce the number of levels necessary to trainthe GAN, we propose a bootstrapping mechanism in whichplayable generated levels are added to the training set. Theresults demonstrate that the new approach does not only gen-erate a larger number of levels that are playable but also gen-erates fewer duplicate levels compared to a standard GAN