Investigation of Dissipation,Adsorption, Degradation,and Leaching of Triazophos Pesticide in Various Soils

This study concerns the investigation of dissipation, adsorption, and degradation of triazophos in different soils from Pakistan. These processes help in the disappearance of pesticide from the environment. Gas chromatography was used for dissipation and adsorption analysis while for degradation study mass spectrometer was used in addition of gas chromatography (GC-MS). The dissipation rate of triazophos in three different soils was 90% over 30 days with average half-life of 9.059 days. From dissipation study it was inferred that rate is variable in each soil due to climatic changes, soil nature and soil-pesticide interactions. Adsorption experiment has revealed that the adsorption of this pesticide to soil follows the pseudo first order kinetic model with rate constant value of 0.479/h and Freundlich isotherm with adsorption capacity of 1.832 mol/g. Degradation study has displayed two major metabolites, one is phosphorothioic acid, S-[2-[(1-cyano-1-methylethyl) amino]-2-oxoethyl] O,O-diethyl ester at retention time of 9.136 and the other is sulfotep at 14.304 min. The leaching potential of triazophos was also calculated from its half-life and organic carbon content present in soil which was 1.688 representing it as non leacher pesticide.     

Carbon nanotubes play an important role in the spatial arrangement of calcium deposits in hydrogels for bone regeneration

Age related bone diseases such as osteoporosis are considered among the main causes of reduced bone mechanical stability and bone fractures. In order to restore both biological and mechanical function of diseased/fractured bones, novel bioactive scaffolds that mimic the bone structure are constantly under development in tissue engineering applications. Among the possible candidates, chitosan-based thermosensitive hydrogel scaffolds represent ideal systems due to their biocompatibility, biodegradability, enhanced antibacterial properties, promotion of osteoblast formation and ease of injection, which makes them suitable for less invasive surgical procedures. As a main drawback, these chitosan systems present poor mechanical performance that could not support load-bearing applications. In order to produce more mechanically-competent biomaterials, the combined addition of hydroxyapatite and carbon nanotubes (CNTs) is proposed in this study. Specifically, the aim of this work is to develop thermosensitive chitosan hydrogels containing stabilised single-walled and multi-walled CNTs, where their effect on the mechanical/physiochemical properties, calcium deposition patterns and ability to provide a platform for the controlled release of protein drugs was investigated. It was found that the addition of CNTs had a significant effect on the sol–gel transition time and significantly increased the resistance to compression for the hydrogels. Moreover, in vitro calcification studies revealed that CNTs played a major role in the spatial arrangements of newly formed calcium deposits in the composite materials studied, suggesting that they may have a role in the way the repair of fragile and/or fractured bones occurs in vivo.     

A multi‐objective evolutionary optimization of fuzzy controller for energy conservation in air conditioning systems

This paper presents the use of evolutionary optimization approach to design and tune smart fuzzy controllers for heating, ventilation, and air conditioning systems or HVAC. The objective is to optimize energy consumption while accounting for user comfort requirements. The problem of energy conservation in air conditioning systems becomes a multi‐objective optimization constrained problem, which enlarges the solution search space. To solve this problem, a multi‐objective evolutionary optimization technique based on genetic algorithm (GA) is proposed. A physical experimental setup is constructed for data collection and formulation of mathematical model. A fuzzy controller is initially designed through expert knowledge, and GA is then used to tune the rules and membership functions of the fuzzy controller in order to optimize multiple objectives. Simulations and real experiments are compared to determine the effectiveness of the proposed strategy. As compared to the controller present in the real experimental air conditioner, approximately 15% energy is successfully saved with no increase in average individual dissatisfaction or discomfort index. Also, a decrease in peak individual dissatisfaction or discomfort index from 91% to 62% is observed. Copyright © 2013 John Wiley & Sons, Ltd.     

Analysis of optimized signal processing algorithms for smart antenna system

By the exponential increase in cellular communication area, the user demands and with their side problems also tend to increase. Several techniques such as cell splitting, frequency reuse, diversity and so on have already been applied to overcome these problems. In all these procedures, smart antenna is one of the best techniques used to boost capacities, enlarge bandwidth, raise the SIR ratios, minimize the effects of fading and improve MIMO communications. An ordinary antenna array which can turn up into a smart antenna array is due to the signal processing algorithms, which consists of angle of arrival (AOA) estimations and Beamforming. In this paper, I will discuss and analyse about the MUSIC algorithm for AOA estimation and least mean squares algorithm for Beamforming.     

A Novel Approach to Motion Control Design for Functionally Related Systems

When a complex task has to be performed by multiple systems, it imposes functional dependencies between the states and/or outputs of the systems. These functional dependencies create a system of’ virtually’ interconnected subsystems, even though they may be physically separated. The component subsystems within the overall system we call ‘functionally related systems’. This paper deals with motion control design for functionally related systems. The design is based on identifying functions. The control design is then performed by projecting the system dynamics into the function space. The main goal is to obtain unit control distribution matrix in the function space and enforce a desired dynamics for each of the identified functions.     

Temperature-Invariant Scaling for Compressible Turbulent Boundary Layers with Wall Heat Transfer

In a recent paper by Zhang et al. in 2012, a Mach number-invariant scaling was proposed to account for the effect of variation of free-stream Mach number in supersonic turbulent boundary layers. The present work focuses on the effect of variation of wall temperature with strong heating and cooling at the wall. Direct numerical simulation is used to study scaling and turbulence structure of a spatially evolving Mach 2 supersonic boundary layer at a friction Reynolds number of 500. A new scaling law is proposed to account for temperature-dependent fluid-property variations. This universal scaling appears superior to the existing models with the novelty that it applies not only for the mean-velocity profile but also extends to the turbulent transport, production, and dissipation terms in the budget of the turbulent kinetic energy.