Neural computing models for prediction of permeability coefficient of coarse-grained soils

Correlations are very significant from the earliest days; in some cases, it is essential as it is difficult to measure the amount directly, and in other cases it is desirable to ascertain the results with other tests through correlations. Soft computing techniques are now being used as alternate statistical tool, and new techniques such as artificial neural networks, fuzzy inference systems, genetic algorithms, and their hybrids were employed for developing the predictive models to estimate the needed parameters, in the recent years. Determination of permeability coefficient (k) of soils is very important for the definition of hydraulic conductivity and is difficult, expensive, time-consuming, and involves destructive tests. In this paper, use of some soft computing techniques such as ANNs (MLP, RBF, etc.) and ANFIS (adaptive neuro-fuzzy inference system) for prediction of permeability of coarse-grained soils was described and compared. As a result of this paper, it was obtained that the all constructed soft computing models exhibited high performance for predicting k. In order to predict the permeability coefficient, ANN models having three inputs, one output were applied successfully and exhibited reliable predictions. However, all four different algorithms of ANN have almost the same prediction capability, and accuracy of MLP was relatively higher than RBF models. The ANFIS model for prediction of permeability coefficient revealed the most reliable prediction when compared with the ANN models, and the use of soft computing techniques will provide new approaches and methodologies in prediction of some parameters in soil mechanics.     

Effect of microwave‐assisted extraction on the release of polyphenols from ginger (Zingiber officinale)

The significance of different variables viz. temperature, time and solvent at constant power in microwave‐assisted extraction (MAE) process of ginger was studied and compared with conventional method. Aqueous ethanol (50%) provided higher yields of extract as well as the highest release of total polyphenols (TPP) than alcoholic solvents. The reason could be the high dielectric constant of aqueous ethanol as compared to alcohols. Microwave heating being a volumetric process, an exposure time of 1 min was found to be sufficient. The better penetration of microwaves and greater solubility at higher temperature resulted in higher yield of TPP and [6]‐gingerol. The resultant extract showed higher radical scavenging activity (RSA) values. Thus, MAE allowed higher recoveries compared to conventional extraction process, with improvement in the quantity and quality of extract in very short period of time.     

Key distribution scheme for peer-to-peer communication in mobile underwater wireless sensor networks

Wireless Sensor Networks (WSN) consist of small battery-limited devices called sensor nodes. The communication between sensor nodes is a type of peer-to-peer communication, since each node has the same capability and role. One of the recent application areas of these nodes is underwater sensing. Communication in Underwater Wireless Sensor Networks (UWSN) is challenging since radio frequencies cannot be used. Instead acoustic waves, which cause extra challenges, are used in UWSN. Since UWSNs are deployed in hostile environment, nodes can be captured by an adversary. In order to secure UWSNs, key distribution problem must be addressed. Moreover, UWSNs are inherently mobile since the nodes may be drifted in the sea. In this paper, we propose a key distribution model which is applied for two group mobility models, namely nomadic mobility model and meandering mobility model. In both schemes hierarchical structure is used and communication is handled via well-known Blom’s key distribution scheme. Our simulation results show that mobility causes some temporary decreases in the connectivity, but our schemes help to heal the connectivity performance in time. Moreover, our schemes show good resiliency performance such that capture of some nodes by an adversary only causes very small amount of links between uncaptured nodes to be compromised.     

Emerging Trends in Microwave Processing of Spices and Herbs

Today, spices are integral part of our food as they provide sensory attributes such as aroma, color, flavour and taste to food. Further their antimicrobial, antioxidant, pharmaceutical and nutritional properties are also well known. Since spices are seasonal so their availability can be extended year round by adopting different preservation techniques. Drying and extraction are most important methods for preservation and value addition to spices. There are different techniques for drying of spices with their own advantages and limitations. A novel, non-conventional technique for drying of spices is use of microwave radiation. This technique proved to be very rapid, and also provide a good quality product. Similarly, there are a number of non-conventional extraction methods in use that are all, in principle, solid–liquid extractions but which introduce some form of additional energy to the process in order to facilitate the transfer of analytes from sample to solvent. This paper reviews latest advances in the use of microwave energy for drying of spices and herbs. Also, the review describes the potential application of microwave energy for extraction of essential oil/bioactive components from spices and herbs and the advantages of microwave-assisted process over the other extraction processes generally employed for extraction. It also showcases some recent research results on microwave drying/extraction from spices and herbs.     

Electrorheological properties and creep behavior of polyindole/poly(vinyl acetate) composite suspensions

In this study, electrorheological (ER) properties of polyindole (PIN) and polyindole/poly (vinyl acetate), (PIN/PVAc) conducting composites having different compositions were investigated. Conductivities and dielectric properties of these composites were determined. The particle sizes of the composites were determined by dynamic light scattering method. Suspensions of PIN and PIN/PVAc composites were prepared in silicone oil, at several concentrations (c = 5–25%, m/m) and their sedimentation stabilities were determined. Then the effects of dispersed particle concentration, shear rate, electric field strength, frequency, and temperature onto ER activities of suspensions were investigated. The flow times of these suspensions at various dc electric field strengths were measured. Further, creep tests were applied to the composite suspensions and a reversible viscoelastic deformation was observed.     

An impression on current developments in the technology, chemistry, and biological activities of ginger (Zingiber officinale Roscoe)

Ginger rhizome (Zingiber officinale Roscoe) is widely cultivated as a spice for its aromatic and pungent components. The essential oil and oleoresins from ginger are valuable products responsible for the characteristic flavor and pungency. Both are used in several food products such as soft beverages and also in many types of pharmaceutical formulations. More than 100 compounds have been reported from ginger, some of which are isolated and characterized, others are tentatively identified by GC-MS and / or LC-MS. [6]-Gingerol, the major gingerol in ginger rhizomes, has been found to possess many interesting pharmacological and physiological activities, such as anti-inflammatory, analgesic, and cardiotonic effects. Ginger is considered as "generally recognized as safe" (GRAS) by Food and Drug Administration (FDA), USA. Due to all these properties, ginger has gained considerable attention in developed countries in recent years, especially for its use in the treatment of inflammatory conditions. The present review is a persuasive presentation of the current information on processing, chemistry, biological activities, and medicinal uses of ginger. Further studies are required for the validation of the beneficial uses. Formulation for novel products and new usages may emerge in the years to come, based on the revealed results of various studies.