Analysis of different configurations of flat plate water collectors connected in series

This paper presents the analytical study of flat plate collector based on the computer‐based thermal models considering two different cases, case A (fully covered by glass) and case B (fully covered by photovoltaic (PV) module). These models are developed based on energy balance equations. An analytical expression for characteristic equation for photovoltaic–thermal flat plate collector has been derived as a function of design and climatic parameters. This paper shows the detailed analysis of energy, exergy and electrical energy by varying the number of collectors by considering four weather conditions (A, B, C and D type) for five different cities (New Delhi, Bangalore, Mumbai, Srinagar and Jodhpur) of India. It is observed that the collectors fully covered by PV module combine the production of hot water in addition to electricity generation and it is beneficial in terms of exergy, thermal energy and electrical energy gain. Copyright © 2008 John Wiley & Sons, Ltd.     

Crosstalk reduction in mixed-signal 3-D integrated circuits with interdevice layer ground planes

We show nearly 8 dB of crosstalk reduction using ground planes between active device layers in three-dimensional (3-D) integrated circuits. Our experimental work utilizes two planes of MOS transistors with tungsten or polysilicon ground planes designed to attenuate crosstalk. Theoretical simulations, using an electromagnetic solver, and the experimental results are consistent with analytical results. The key result verified is that a ground plane, whose footprint shadows the device area, is sufficiently large for effective attenuation. The interdevice layer ground plane provides an effective means to achieve crosstalk reduction in 3-D mixed-signal/RF integration because of simple fabrication and high coupling isolation.     

Simplified loss analysis and comparison of full-bridge,full-range-ZVS DC-DC converters

The loss of zero-voltage-switching (ZVS) of active switches has been a serious limitation of full-bridge (FBZVS) converters. Many techniques have been proposed in the past to extend the range of ZVS operation over the wider and also the full range of operation. However, in these techniques ZVS is achieved at the expense of additional conduction loss in active switches and losses in the auxiliary components. In this paper, the analysis for the additional losses in various full-range FBZVS DC-DC converters and their comparative evaluation is reported. Closed form expressions are derived for average value of device currents and losses. The loss curves for various topologies are plotted and compared. The analytical results are found to be consistent with the experimental efficiency tests performed on 500 W, 100 kHz prototype. It is concluded that a recently proposed new topology has the least penalty of additional losses.     

Electron microscopic observations of Bi and Tl bearing cuprate high temperature superconductors

The second generation of high temperature superconductors typified by Bi₂Sr₂Ca _n−1Cu _n O_2n+4 and Tl₂Ba₂Ca _n−1Cu _n O_2n+4 exhibits curious structural properties which have direct relevance to the superconducting behaviour particularly transition temperature (T _c ). The present paper reports on investigations of structural properties at microlevel in Bi-bearing HTCS. We have found curious structural characteristics which manifests itself in the form of transformation froma _p ×a _p ×c to (2)^1/2 a _p ×(2)^1/2 a _p ×c through the loss of calcium atoms and the formation of five-fold modulated phase alongb through the loss of Ca and Sr atoms. We have also found the evidence of high periodicities (n=4) Bi₂Sr₂Ca₃Cu₄O₁₂. The microstructural characteristics of HTCS showing the higherT _c (R=0) ∼ 120 K exhibits unusual characteristics.     

Solar radiation models—A review

Solar radiation models for predicting the average daily and hourly global radiation, beam radiation and diffuse radiation on horizontal surface are reviewed in this article. Estimations of monthly average hourly global radiation from daily summations are discussed. It was observed that Collares‐Pereira and Rabl model as modified by Gueymard (CPRG) yielded the best performance for estimating mean hourly global radiation incident on a horizontal surface for Indian regions. Estimations of monthly average hourly beam and diffuse radiation are discussed. It was observed that Singh‐Tiwari and Jamil‐Tiwari both models generally give better results for climatic conditions of Indian regions. Therefore, their use is recommended for composite climate of Indian regions. Empirical correlations developed to establish a relationship between the hourly diffuse fraction and the hourly clearness index using hourly global and diffuse irradiation measurements on a horizontal surface are discussed. Fifty models using the Angstrom–Prescott equation to predict the average daily global radiation with hours of sunshine are considered. It was reported that Ertekin and Yaldiz model showed the best performance against measured data of Konya, Turkey. Copyright © 2010 John Wiley & Sons, Ltd.     

A survey on review summarization and sentiment classification

Knowledge and Information Systems - With increasingly more people using online services, purchasing products, and reviewing them, it becomes crucial to have a system that can provide a crisp...     

Identifying crop water stress using deep learning models

Neural Computing and Applications - The identification of water stress is a major challenge for timely and effective irrigation to ensure global food security and sustainable agriculture. Several...     

Energy-optimized cluster head selection based on enhanced remora optimization algorithm in underwater wireless sensor network

With the technological advancements, wireless sensor network (WSN) has played an impeccable role in monitoring the underwater applications. Underwater WSN (UWSN) is supported by WSN but subjected to data dissemination in an acoustic medium. Due to challenging conditions in underwater scenario, the limited battery resources of these sensor nodes stem to a crucial research problem that needs to address the energy-efficient routing in UWSN. In this research work, we intend to propose an energy-optimized cluster head (CH) selection based on enhanced remora optimization algorithm (ECERO) in UWSN. Since CH devours the maximum energy among the nodes, we perform selection of CH based on EROA while considering energy, Euclidean distance from sink, node density, network's average energy, acoustic path loss model and lastly, the adaptive quantity of CHs in the network. Further, to reduce the load on CH node, we introduce the concept of sleep scheduling among the closely located cluster nodes. The proposed work improves the performance of recently proposed EOCSR algorithm by great magnitude which claims to mitigate hot-spot problem, but EOCSR still suffers from the same due to relaying a large magnitude of data.     

Prediction of Alzheimer’s Using Random Forest with Radiomic Features

Alzheimer’s disease is a non-reversible, non-curable, and progressive neurological disorder that induces the shrinkage and death of a specific neuronal population associated with memory formation and retention. It is a frequently occurring mental illness that occurs in about 60%–80% of cases of dementia. It is usually observed between people in the age group of 60 years and above. Depending upon the severity of symptoms the patients can be categorized in Cognitive Normal (CN), Mild Cognitive Impairment (MCI) and Alzheimer’s Disease (AD). Alzheimer’s disease is the last phase of the disease where the brain is severely damaged, and the patients are not able to live on their own. Radiomics is an approach to extracting a huge number of features from medical images with the help of data characterization algorithms. Here, 105 number of radiomic features are extracted and used to predict the alzhimer’s. This paper uses Support Vector Machine, K-Nearest Neighbour, Gaussian Naïve Bayes, eXtreme Gradient Boosting (XGBoost) and Random Forest to predict Alzheimer’s disease. The proposed random forest-based approach with the Radiomic features achieved an accuracy of 85%. This proposed approach also achieved 88% accuracy, 88% recall, 88% precision and 87% F1-score for AD vs. CN, it achieved 72% accuracy, 73% recall, 72% precisionand 71% F1-score for AD vs. MCI and it achieved 69% accuracy, 69% recall, 68% precision and 69% F1-score for MCI vs. CN. The comparative analysis shows that the proposed approach performs better than others approaches.     

Enlarged Photonic Band Gap in Heterostructure of Metallic Photonic and Superconducting Photonic Crystals

We show theoretically that the frequency range of photonic band gap of a hetero-structure which is made of a metallic photonic and superconducting photonic crystal can be enlarged due to the combination of the reflection band properties of the superconductor–dielectric (PC1) and metallic–dielectric (PC2) periodic structures. The transmittance and band structure of the considered structures are calculated using simple transfer matrix method and the Bloch theorem. Beside this, we have also calculated the transmittance of the superconducting photonic structure (PC1), metallic photonic structure (PC2) and heterostructure of metallic photonic and superconductor photonic crystals (PC1/PC2) for TE and TM-mode at the different angles of incidence.