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21.
Huddar Mahesh G. Sannakki Sanjeev S. Rajpurohit Vijay S. 《Multimedia Tools and Applications》2021,80(9):13059-13076
Multimedia Tools and Applications - Due to the availability of an enormous amount of multimodal content on the social web and its applications, automatic sentiment analysis, and emotion detection... 相似文献
22.
Many algorithms for cell formation have been developed for past three decades in cellular manufacturing. Some use binary data for cell formation and others use production data such as operation sequence, processing times, production volumes, etc. for cell formation. All these algorithms assume that the conversion of job shop to cellular manufacturing is performed comprehensively. (In other words, they assume that all the cells are formed at a time.) However, this is far from reality. In practice, cell formation is done incrementally, one after the other, rather than comprehensively. None of the algorithms developed so far addresses the issue of incremental cell formation. In this paper, the incremental cell formation problem is defined and various categories of problems are mentioned. One type of those categories is selected for solving. Two methods, namely the branch and bound technique and a heuristic based on a multistage programming approach, have been applied to solve the chosen problem. Data sets have been generated to compare these two methods in terms of quality of solution and demand on computational time. It has been found that the branch and bound technique gives a superior quality solution, but is computationally more demanding, where as heuristic based on a multistage programming approach is computationally far superior. 相似文献
23.
In this paper, a new approach for optimally sizing the storage system employing the battery banks for the suppression of the output power fluctuations generated in the hybrid photovoltaic/wind hybrid energy system. At first, a novel multiple averaging technique has been used to find the smoothing power that has to be supplied by the batteries for the different levels of smoothing of output power. Then the battery energy storage system is optimally sized using particle swarm optimization according to the level of smoothing power requirement, with the constraints of maintaining the battery state of charge and keeping the energy loss within the acceptable limits. Two different case studies have been presented for different locations and different sizes of the hybrid systems in this work. The results of the simulation studies and detailed discussions are presented at the end to portrait the effectiveness of the proposed method for sizing of the battery energy storage system. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
24.
N. G. Shiva Prasad G. V. Ashok H. M. Mahesh 《The International journal of environmental studies》2013,70(1):83-92
Potable waters from various locations of the Bangalore environment were investigated for their 222Rn concentrations by the emanometry method. About 94 groundwater (borewell) samples were analysed for 222Rn concentrations and found to vary in the range 5.3–283.4 Bq L?1 with a mean value of 87 Bq L?1. Frequency distribution showed the 222Rn concentration in a large number of samples in the range of 0–50 Bq L?1. From the measured concentrations, the effective doses (lung and stomach) for the population of the region were estimated. The effective dose was found to vary from 42.6 to 2280.2 µSv y?1 with a mean value 702.5 µSv y?1. The effect of boiling of water showed a drastic reduction in the 222Rn concentration. The results of the present investigation are systematically analysed, compared with the literature values and discussed. 相似文献
25.
A novel approach for extracting cellulose nanofibers from lignocellulosic biomass by ball milling combined with chemical treatment 下载免费PDF全文
Cellulose nanofibers (CNFs) were isolated from kenaf fibers and wheat straw by formic acid (FA)/acetic acid (AA), peroxyformic acid (PFA)/peroxyacetic acid (PAA), hydrogen peroxide (H2O2) treatment; and subsequently through ball milling treatment. Characterization of extracted cellulose and cellulose nanofibers was carried out through Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X‐ray diffraction (XRD), and thermogravimetric analysis (TGA). TEM images showed that extracted cellulose nanofibers had diameter in the range of 8–100 nm. FTIR and XRD results implied that hemicellulose and lignin were mostly removed from lignocellulosic biomass with an increase in crystallinity, and isolation of cellulose nanofibers was successful. The TGA results showed that decomposition temperature of cellulose nanofibers increased by about 27°C when compared with that of untreated lignocellulosic biomass. No significant change was observed in the decomposition temperature of bleached celluloses after ball milling. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 42990. 相似文献
26.
Soluble‐eggshell‐membrane‐protein‐modified porous silk fibroin scaffolds with enhanced cell adhesion and proliferation properties 下载免费PDF全文
In this study, a porous silk fibroin (SF) scaffold was modified with soluble eggshell membrane protein (SEP) with the aim of improving the cell affinity properties of the scaffold for tissue regeneration. The pore size and porosity of the prepared scaffold were in the ranges 200–300 μm and 85–90%, respectively. The existence of SEP on the scaffold surface and the structural and thermal stability were confirmed by energy‐dispersive X‐ray spectroscopy, X‐ray diffraction, Fourier transform infrared spectroscopy, differential scanning calorimetry, and thermogravimetric analysis. The cell culture study indicated a significant improvement in the cell adhesion and proliferation of mesenchymal stem cells (MSCs) on the SF scaffold modified with SEP. The cytocompatibility of the SEP‐conjugated SF scaffold was confirmed by a 3‐(4,5‐dimethyltriazol‐2‐y1)‐2,5‐diphenyl tetrazolium assay. Thus, this study demonstrated that the biomimic properties of the scaffold could be enhanced by surface modification with SEP. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40138. 相似文献
27.
Moisture diffusion through (hexadecyltrimethylammonium bromide ‐ Indian bentonite)/(vinylester) nanocomposites in artificial seawater and demineralized water 下载免费PDF全文
N. Raghavendra H. N. Narasimha Murthy Salim Firdosh R. Sridhar Gangadhar Angadi K. R. Vishnu Mahesh M Krishna 《乙烯基与添加剂工艺杂志》2016,22(4):441-451
This paper compares the moisture diffusion properties of organomodified (Indian Bentonite nanoclay)/vinylester containing different amounts of nanoclay on exposure to demineralized water and artificial seawater at room temperature. Moisture uptake behavior of (Indian Bentonite)/vinylester was investigated and compared with that of neat vinylester. Addition of 5 wt% nanoclay decreased the diffusivity and permeability of vinylester in artificial seawater medium, but these diffusion parameters increased in demineralized water medium. Degradation in glass transition temperature and microhardness of the nanocomposites were much greater in specimens aged in demineralized water than in those in artificial seawater medium. Moisture diffusion behavior of the specimens was analyzed by Fick's law and the Langmuir model. The aged specimens were chemically analyzed by using infrared spectroscopy after aging for 146 days. A significant amount of leached organic species was detected in the demineralized water–aged specimens but the same was absent in those aged in artificial seawater. J. VINYL ADDIT. TECHNOL., 22:441–451, 2016. © 2015 Society of Plastics Engineers 相似文献
28.
Previous studies on concrete have identified silica fume (SF) as the most effective supplementary material, whereas fly ash (FA) and slag have been identified as economical materials with long term strength potential. Development of blended cement mortar referred to as blended mortar (BM) requires similar assessment. The present study explores the application of Alccofine (AL) as supplementary material and compares its performance with conventional materials namely SF, FA and ground granulated blast furnace slag (GGBS). The mortar specimens with binder to fine-aggregates (b/f ) ratio of 1:2 are prepared at water to binder (w/b) ratios of 0.4 and 0.35. The strength values and stress-strain curve for control and BM specimens are obtained at 7, 28, 56, and 90 d curing periods. The assessment based on strength activity index, k-value method and strength estimation model confirms that AL, despite lower pozzolanic activity, contributes to strength gain, due to reduced dilution effect. Assessment of stress-strain curves suggests that the effect of w/b ratio is more dominant on the elastic modulus of BM specimens than on control specimens. The observations from the study identify enhanced strength gain, improved elastic modulus and higher energy absorption as key contributions of AL making it a potential supplementary material. 相似文献
29.
Paul V. Shanahan Lianbin Xu Chengdu Liang Mahesh Waje Sheng Dai Y.S. Yan 《Journal of power sources》2008
Highly stable graphitic mesoporous carbons (GMPCs) are synthesized by heat-treating polymer-templated mesoporous carbon (MPC) at 2600 °C. The electrochemical durability of GMPC as Pt catalyst support (Pt/GMPC) is compared with that of carbon black (Pt/XC-72). Comparisons are made using potentiostatic and cyclic voltammetric techniques on the respective specimens under conditions simulating the cathode environment of PEMFC (proton exchange membrane fuel cell). The results indicate that the Pt/GMPC is much more stable than Pt/XC-72, with 96% lower corrosion current. The Pt/GMPC also exhibits a greatly reduced loss of catalytic surface area: 14% for Pt/GMPC vs. 39% for Pt/XC-72. 相似文献
30.
Computational fluid dynamics (CFD) simulations have been carried out to simulate a turbulent, bubble plume in a liquid pool. A two-fluid enhanced k-? model has been used, with the extra source terms introduced to account for the interaction between the bubbles and the liquid and transient calculations have been performed to study the plume growth, the acceleration of the liquid due to viscous drag, and the approach to steady-state conditions. In order to obtain correct spreading of the plume observed experimentally, it was observed that interfacial forces like lift and turbulent dispersion plays important role. The sensitivity analysis for drag coefficient and two different turbulent dispersion forces is presented. The development of the flow variables has been compared with the experimental data. From the CFD predictions obtained in the present work, it can be concluded that a two-dimensional (2D) axisymmetric assumption in this case is justified, with 2D model predictions in good agreement with the experimental data and those of a three-dimensional (3D) model, except for the shear stresses and turbulent kinetic energy. In general, quantitative comparison with the experimental data has revealed that, by applying proper models of inter-phase momentum transfer, and performing simulations based on the two-fluid model, satisfactory predictions of mean flow quantities can be obtained for this application away from the injector. 相似文献