Environmental and power generation implications of efficient electrical appliances for India

We analyse the potentials of selected efficient appliances (EAs) for air pollutant mitigation and reducing the need for rapidly escalating power generation in India from the national, utility and user perspectives. The study shows that about 10.1% of total cumulative generation and about 7.4, 8.7 and 9.8% of total cumulative CO₂, SO₂ and NO_x emissions, respectively, could be avoided between 1997 and 2015 by using EAs. At currently prevailing electricity and appliance prices, cost-effective levels of avoided generation and air pollutant mitigation potentials are significantly lower from the users' viewpoint. The level of air pollutant mitigation would be significantly higher if an efficient electricity pricing policy were adopted and if relatively low interest loans were available for the purchase of EAs.     

Omega-6 and Omega-3 Fatty Acid-Derived Oxylipins from the Lipoxygenase Pathway in Maternal and Umbilical Cord Plasma at Delivery and Their Relationship with Infant Growth

Omega-3 and omega-6 fatty acids are important for neonatal development and health. One mechanism by which omega-3 and omega-6 fatty acids exert their effects is through their metabolism into oxylipins and specialized pro-resolving mediators. However, the influence of oxylipins on fetal growth is not well understood. Therefore, the objective of this study was to identify oxylipins present in maternal and umbilical cord plasma and investigate their relationship with infant growth. Liquid chromatography–tandem mass spectrometry was used to quantify oxylipin levels in plasma collected at the time of delivery. Spearman’s correlations highlighted significant correlations between metabolite levels and infant growth. They were then adjusted for maternal obesity (normal body mass index (BMI: ≤30 kg/m²) vs. obese BMI (>30 kg/m²) and smoking status (never vs. current/former smoker) using linear regression modeling. A p-value < 0.05 was considered statistically significant. Our study demonstrated a diverse panel of oxylipins from the lipoxygenase pathway present at the time of delivery. In addition, both omega-3 and omega-6 oxylipins demonstrated potential influences on the birth length and weight percentiles. The oxylipins present during pregnancy may influence fetal growth and development, suggesting potential metabolites to be used as biomarkers for infant outcomes.     

Low temperature MBE of GaAs: A theoretical investigation of RHEED Oscillations

Surface dynamics dominate the temporal variation of reflection high energy electron diffraction (RHEED) intensity in the low temperature molecular beam epitaxy (MBE) of (100) gallium arsenide (GaAs). A rate equation model is proposed which includes the presence and dynamics of a physisorbed arsenic (PA) layer riding the growth surface. Using the results of the temporal evolution of the surface, the RHEED intensity is computed based on kinematical theory of electron diffraction with an As-As interplanar distance of 2.48 Å for the physisorbed As layer and a (100) Ga-As crystalline interplanar distance of 1.41 Å. The model results show ROs at low and high temperatures but not in the intermediate range of 300–450°C which is in good agreement with experiments. At low temperatures, the surface is covered by the PA layer whose vertical distribution across the layers depends upon that of the underlying crystalline surface. Thus a temporal variation of the step density of the crystalline GaAs surface results in step density variation of the PA layer which, in turn, yields ROs. Since the height of the PA layer is uniformly 2.48Å in this case, the RHEED beam sees a step height equal to the GaAs interplanar distance of 1.41Å, and the specular intensity of the RHEED beam will respond to the temporal variations in the underlying GaAs surface, yielding ROs if the growth is layer-by-layer. At high temperatures the crystalline GaAs is exposed to the RHEED beam due to evaporation of PA layer and the ROs appear due to periodic step density oscillations with a step height of 1.41Å which is the Ga-As crystalline interplanar distance. At intermediate temperatures, the partial coverage of the surface by the PA layer and crystalline GaAs, coupled with very different interplanar distances in these layers, results in a complete destructive interference of the RHEED intensity. The RO dependence on the As BEP is also presented and discussed.     

Interpretable machine learning learns complex interactions of urban features to understand socio-economic inequality

Inequality in cities is a phenomenon arising from the complex interactions among urban systems and population activities. Conventional statistics and mathematical models like multiple regression models require assumptions of feature interactions with specified mathematical forms that may fail to fully capture complex interactions of heterogeneous urban components, creating challenges in systematically assessing socio-economic inequality in cities. To overcome the limitations of these conventional mathematical models, in this work, we propose an interpretable machine learning model to capture the complex interactions of urban variables and the main interaction effects on socio-economic statuses. We extract urban features from high-resolution anonymized mobile phone data with billions of activity records related to people and facilities in 47 US metropolitan areas and predict the attributes of urban areas from six income and race groups. We show that socio-economic inequality in cities can be effectively measured by the predictability of trained machine learning models in controlled experiments. We also examine the tradeoff between spatial resolution, sample size, and model accuracy; test the presence of influential features; and measure the transferability of the trained models to identify the optimal values for controlled factors. The results show that metropolitan areas share similar patterns of inequality, which could be moderated by improved polycentric facility distribution and road density. The generality of associated factors and transferability of machine learning models can help bridge data gaps between cities and inform about inequality alleviation strategies. Despite similarities, 50% to 90% of variations among cities are still present, which shows the need for localized policies for inequality alleviation and mitigation. Our study shows that machine learning models could be an effective approach to examine inequality, which opens avenues for more data-centric and complexity-informed planning, design, policymaking, and engineering toward equitable cities.     

Multi‐carrier platform for wireless communications. Part 1: High‐performance,high‐throughput TDMA and DS‐CDMA via multi‐carrier implementations

Multi‐carrier technologies in general, and OFDM and MC‐CDMA in particular, are quickly becoming an integral part of the wireless landscape. In this first of a two‐part survey, the authors present the innovative transmit/receive multi‐carrier implementation of TDMA and DS‐CDMA systems. Specifically, at the transmit side, the pulse shape (in TDMA) and the chip shape (in DS‐CDMA) corresponds to a linear combining of in‐phase harmonics (called a CI signal). At the receiver side, traditional time‐domain processing (equalization in TDMA and RAKE reception in DS‐CDMA) is replaced by innovative frequency based processing. Here, receivers decompose pulse (or chip) shapes into carrier subcomponents and recombine these in a manner achieving both high frequency diversity gain and low MAI. The resulting system outperforms traditional TDMA and DS‐CDMA systems by 10–14 dB at typical BERs, and, by application of pseudo‐orthogonal pulse shapes (chip shapes), is able to double system throughput while maintaining performance gains of up to 8 dB. Copyright © 2002 John Wiley & Sons, Ltd.     

Studies on fly ash/coir/sugarcane reinforced epoxy polymer matrix composite

In the past years studies were conducted on natural fibre reinforced polymer composites to observe their mechanical properties in order to decide their industrial applications. These composites have already been used in many applications from aerospace to sporting equipment. These green composites can be used as a replacement for synthetic composites. This is because the natural fibres are eco-friendly, biodegradable, renewable, etc. In this work, an attempt is made to reinforce fly ash, coir fibre and sugarcane fibre with epoxy polymer matrix. Central composite design under response surface methodology (RSM), one of the approaches of design of experiments (DOE) is used to determine optimum sample preparation conditions of fly ash, coir fibre and sugarcane fibre. Both tensile and flexural (three-point bending) tests are conducted on these fabricated composites to determine their materialistic characteristics. Analysis of variance (ANOVA) is carried out using Minitab software to find the influence of fly ash, coir fibre, sugarcane fibre on composites. Regression equations obtained from analysis of variance is used to calculate values. Experimental and calculated values are compared and their error % are calculated and tabulated. Response surface optimization study is carried to find the optimized parameters of composites. It is observed that, increase in wt.% of coir fibre and decrease in wt.% of fly ash and sugarcane fibre, increases yield stress and these parameters have mixed impact on ultimate tensile stress. The addition of fly ash, coir fibre and sugarcane fibre in low percentages increases Young's modulus. Increase in wt.% of fly ash and coir fibre and decrease in wt.% of sugarcane, increases flexural modulus and flexural stress.     

Biochar supported manganese based catalyst for low-temperature selective catalytic reduction of nitric oxide

Clean Technologies and Environmental Policy - This research work aims to study the performance of biochar-supported manganese-based catalysts for conversion of NOx in the selective catalytic...     

Experimental Investigations on the Mechanical Properties,Microstructure and Corrosion Effect of Cu-20Al-4Ni/SiC Composites Synthesized Using Powder metallurgy Route

Silicon - The present investigation pertains to synthesize aluminium bronze silicon carbide composite by powder metallurgy route. Three various weight percentages of silicon carbide (0, 2, 4...     

DisGeReExT: a knowledge discovery system for exploration of disease–gene associations through large-scale literature-wide analysis study

Knowledge and Information Systems - Objective Advanced experimental methods such as next-generation sequencing (NGS) produced a large number of potential indicative genetic biomarkers and gene...