Thermosolutal convection in a fluid‐porous composite medium

In the present study analysis has been performed for thermosolutal convection in a fluid‐porous composite medium, consisting of a fluid‐saturated porous medium followed by an overlaying clean medium. The fluid‐porous composite medium is subjected to both a horizontal solutal and a thermal gradient. Top and bottom walls of the fluid‐porous composite medium are assumed to be impermeable and adiabatic. The Darcy‐Brinkman‐Forchheimer model is used to study the flow through the fluid‐porous composite medium. A single domain approach is taken into consideration for numerical simulation. The solution is done by control volume integration. A comprehensive analysis has been performed for various pertinent parameters to delineate their behavior. Results of the transport phenomenon have been provided in graphical and tabular form, for the complete understanding of the complex phenomenon. © 2013 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library (wileyonlinelibrary.com/journal/htj). DOI 10.1002/htj.21048     

Flame stability studies in a hydrogen-air premixed flame annular microcombustor

Flame stability in an annular heat recirculating microcombustor burning stoichiometric hydrogen-air mixture was explored by means of a rigorous thermal analysis. The analysis is based on computational fluid dynamics model of reacting fluid flow accounting for interactions in flow, species, and conjugate thermal field in fluid and solid. Consideration of thermal diffusion effects in the model was necessary for realistic predictions in all the cases. Flame stability under different inlet velocity and wall thermal conductivities was studied. Results showed that a stable flame could stabilize in this combustor in the velocity range of 3-35 m/s. However, the upper stability limit widened for lower wall thermal conductivity. Low velocity flashback and high velocity blowout bounded the stability region with respect to inlet velocity for lower thermal conductivity wall material. Lower flame stability limit was influenced by thermal design of the microcombustor that prevented flame extinction and ability of flame to stabilize at the heated wall even at higher inlet velocity controlled the upper flame stability limit. Flame established well within the combustor for the lowest wall thermal conductivity without blowout and approached flashback for the highest conductivity when wall thermal conductivity was varied at constant inlet velocity. Relative importance of axial and radial wall heat conduction in flame stabilization was explored at the extremes of operating conditions. Both the components played equally important roles in flame stabilization by influencing heat recirculation and losses within the microcombustor. A suitable combination of structural materials could provide a stable flame with high surface temperatures in a lightweight system.     

Systematic analysis of deficits in visual attention.

A variety of impairments in visual attention can follow damage to the brain. The authors develop systematic methods for analyzing such impairments in terms of C. Bundesen's (see record 1991-03287-001) Theory of Visual Attention and apply these in a group of 9 patients with parietal lobe lesions and variable spatial neglect. In whole report, patients report letters from brief, vertical arrays in left or right visual field. The results show substantial, largely bilateral impairments in processing capacity, implying a major nonlateralized aspect to neglect. In partial report, arrays contain 1 or 2 letters in red and/or green. The task is to report only those letters in a specified target color. In addition to the expected bias against left-sided letters, patients show striking, bilateral preservation of top-down control, or attentional priority for targets. The results show how differentiation of attentional impairments can be informed by a theory of normal function. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Delineation and mapping of coal mine fire using remote sensing data – a review

Various countries around the globe face numerous hazards due to the burning of coal on the surface as well as below ground. Countries like China, India, United States of America (USA), Australia, Indonesia, and many other countries have reported the burning of coal fires, and thus it is the urgent need to control the coal fire propagation to prevent the loss of energy resources. Coal is a fossil fuel that has a tendency to catch fire for many reasons; spontaneous combustion being the most frequent reasons for its burning. Other factors leading to coal fire include forest fires close to coal seams, natural hazards, old mining techniques, and external heat sources. The review work demonstrates the application of various satellite data in fire detection and mapping. The literature reveals that remote sensing plays an important role in facilitating quick and complete delineation of coal mine fires. Many algorithms have been developed around the world for fire detection from different satellite data. A comprehensive demonstration of different algorithms along with their merits and demerits are outlined. Comparative performances of the different algorithms with their case studies are also explained. It can be inferred from the various literature that it is very difficult to select a particular sensor algorithm for generating global fire products. Suggestions are given to further explore the possibility of improvement of fire detection algorithms.     

Prediction of Cardiovascular Disease Using Machine Learning Technique—A Modern Approach

Cardio Vascular disease (CVD), involving the heart and blood vessels is one of the most leading causes of death throughout the world. There are several risk factors for causing heart diseases like sedentary lifestyle, unhealthy diet, obesity, diabetes, hypertension, smoking and consumption of alcohol, stress, hereditary factory etc. Predicting cardiovascular disease and improving and treating the risk factors at an early stage are of paramount importance to save the precious life of a human being. At present, the highly stressful life with bad lifestyle activities causes heart disease at a very young age. The main aim of this research is to predict the premature heart disease based on machine learning algorithms. This paper deals with a novel approach using the machine learning algorithm for predicting the cardiovascular disease at the premature stage itself. Support Vector Machine (SVM) is used for segregating the CVD patients based on their symptoms and medical observation. The experimentation results by using the proposed method will facilitate the medical practitioners to provide suitable treatment for the patients on time. A sophisticated model has been developed with the current approach to examine the various stages of CVD and the performance metrics used have given effective and fruitful results as compared to other machine learning techniques.     

Indian Science Reports: a web-based scientometric portal for mapping Indian research competencies at overall and institutional levels

Scientometrics - The article presents an introduction to a newly created scientometric portal called Indian Science Reports, available at www.indianscience.net . The portal is designed to fulfil...     

Finding patterns in the degree distribution of real-world complex networks: going beyond power law

Pattern Analysis and Applications - The most important structural characteristics in the study of large-scale real-world complex networks in pattern analysis are degree distribution. Empirical...     

Monitoring the changes in soil potassium by extraction procedures and electroultrafiltration (EUF) in a Tropaquept under twenty years of rice-rice cropping

Chemical extraction procedures and electroultrafiltration (EUF) fractions were evaluated for measuring the changes in soil K in a Tropaquept as a consequence of continuous fertilizer use and rice-rice cropping for 20 years in a long-term fertilizer experiment. During the course of 20 years the gap in total K uptake by crops in treatments receiving K and those without an external K supply widened, indicating a stress on soil K reserves in the latter treatments. Readily available forms, i.e. water-soluble, 0.01 MCaCl₂, citric acid and ammonium acetate extractable K did not undergo much change. On the contrary, there was a conspicuous decrease in strongly held 3 M H₂SO₄ and 1 M boiling HNO₃ K (nonexchangeable K), as these forms replenished the soil solution K removed by the crop plants. Similarly, considerable decrease was noticed in EUF 30–35 K obtained at higher temperature and voltage, as it also represents nonexchangeable K in soils. NPK and NPK plus FYM arrested, to a greater extent, the depletion in soil K. Huge K removals, from 1000 to 3550 kg K ha^-1, by the rice crop in 20 years were not reflected in NH₄OAc K which is commonly used as a criterion for fertilizer K recommendations by the soil testing laboratories in India. The total K uptake by the rice crop during 20 years corresponded closely to the changes in nonexchangeable K as measured by 3 M H₂SO₄ and 1 M HNO₃. This suggests the need for including nonexchangeable K in soil test calibration for better K fertilizer recommendations in long-term operations.     

Enhanced hydroformylation by carbon dioxide‐expanded media with soluble Rh complexes in nanofiltration membrane reactors

A novel process for continuous hydroformylation in CO₂‐expanded liquids (CXLs) is demonstrated using bulky phosphite ligands that are effectively retained in the stirred reactor by a nanofiltration membrane. The reactor is operated at 50°C with a syngas pressure of 0.6 MPa to avoid CO inhibition of reaction rate and selectivity. The nanofiltration pressure is provided by ～3.2 MPa CO₂ that expands the hydroformylation mixture and increases the H₂/CO ratio in the CXL phase resulting in enhanced turnover frequency (～340 h^?1), aldehydes selectivity (>90%) and high regioselectivity (n/i ～8) at nearly steady operation. The use of pressurized CO₂ also reduces the viscosity in the CXL phase, thereby improving the mass‐transfer properties. Constant permeate flux is maintained during the 50 h run with Rh leakage being less than 0.5 ppm. This technology concept has potential applications in homogeneous catalytic processes to improve resource utilization and catalyst containment for practical viability. © 2013 American Institute of Chemical Engineers AIChE J, 59: 4287–4296, 2013