Optimal Crop Water Allocation in Case of Drought Occurrence,Imposing Deficit Irrigation with Proportional Cutback Constraint

Optimal crop water allocation has become more challenging in drier areas of the world (short of rainfall) due to increased water scarcity and more frequent droughts. alternative cropping patterns, reallocation of water resources and modification of irrigation are some of the strategies used to address droughts . A new optimization model is used in this study to find the optimal cropping patterns during droughts, while benefiting from deficit irrigation to decrease the total allocated water. Moreover, the proposed model is subjected to a proportional cutback constraint to meet optimized proportional water allocation under limited water condition. As a real case study, two related districts, namely Neku-abad and Abshar located in Zayandeh-rud River basin are considered. Zayandeh-rud river basin is located in the central part of Iran. For better illustration of model outputs, the proposed model was checked using various irrigation efficiency values (60–100 % in 10 % interval), water reduction ratios (0.0–0.4) and cutback parameters (λ _a ?=?0.3,?λ _n ?=?0.7, λ _a ?=?0.51,?λ _n ?=?0.49 and λ _a ?=?λ _n ?=?0.5). The results showed that the values of λ _a ?=?0.51,?λ _n ?=?0.49 presents the maximum proportionality in terms of water reduction among all the allocation units or users. Although different values of cutback parameters (e.g.: λ _a ?=?0.3,?λ _n ?=?0.7) maximize net benefits, they are not considered as proportionate decisions in the considered study area.     

Evaluation of the Topographical Surface Changes of Silicon Wafers after Annealing and Plasma Cleaning

Silicon - The morphological stability of silicon single crystal wafers was investigated, after performing cleaning surface treatments based on moderate temperature annealing and plasma sputtering....     

A symmetric quantum-dot cellular automata design for 5-input majority gate

By the inevitable scaling down of the feature size of the MOS transistors which are deeper in nanoranges, the CMOS technology has encountered many critical challenges and problems such as very high leakage currents, reduced gate control, high power density, increased circuit noise sensitivity and very high lithography costs. Quantum-dot cellular automata (QCA) owing to its high device density, extremely low power consumption and very high switching speed could be a feasible competitive alternative. In this paper, a novel 5-input majority gate, an important fundamental building block in QCA circuits, is designed in a symmetric form. In addition to the majority gate, a SR latch, a SR gate and an efficient one bit QCA full adder are implemented employing the new 5-input majority gate. In order to verify the functionality of the proposed designs, QCADesigner tool is used. The results demonstrate that the proposed SR latch and full adder perform equally well or in many cases better than previous circuits.     

Can combining economizers with improved filtration save energy and protect equipment in data centers?

Economizer use in data centers is an energy efficiency strategy that could significantly limit electricity demand in this rapidly growing economic sector. Widespread economizer implementation, however, has been hindered by potential reliability concerns associated with exposing information technology equipment to particulate matter of outdoor origin. This study explores the feasibility of using economizers in data centers to save energy while controlling particle concentrations with high-quality air filtration. Physical and chemical properties of indoor and outdoor particles were analyzed at an operating northern California data center equipped with an economizer under varying levels of air filtration efficiency. Results show that when improved filtration is used in combination with an economizer, the indoor/outdoor concentration ratios for most measured particle types were similar to levels when using conventional filtration without economizers. An energy analysis of the data center reveals that, even during the summer months, chiller savings from economizer use greatly outweigh any increase in fan power associated with improved filtration. These findings indicate that economizer use combined with improved filtration could reduce data center energy demand while providing a level of protection from particles of outdoor origin similar to that observed with conventional design.     

Crosslinked methyl methacrylate/ethylene glycol dimethacrylate polymer compounds with a macroazoinitiator

A silane‐containing diamine, bis(p‐aminophenoxy) diphenylsilane (BADPS), was prepared by the condensation of p‐aminophenol with dichlorodiphenyl silane in the presence of triethylamine. Then, BADPS was condensed with 4,4‐azobis(4‐cyanopentanoyl chloride) to prepare macroazoinitiators containing silane units (Si–MAIs). A series of poly(methyl methacrylate) gels containing silane were derived by the solution free‐radical crosslinking copolymerization of methyl methacrylate and ethylene glycol dimethacrylate monomers initiated by these macroazoinitiators at a total monomer concentration of 6 mol/L and 80°C. Si–MAIs were characterized with ¹H‐NMR and ¹³C‐NMR spectroscopy, and the structural characteristics of the gels were also examined. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Depletion of cross‐stream diffusion in the presence of viscoelasticity

An effort to analyze the viscoelasticity effects on transverse transport of neutral solutes between two miscible streams in an electrokinetic T‐sensor is presented. The analysis is based on an approximate analytical solution for the depthwise averaged concentration, assuming a channel of large width to depth ratio for which a one‐dimensional profile is sufficient for describing the velocity field. We show that the solution derived is surprisingly accurate even for very small channel aspect ratios and the maximum error reduces to only about 1% when the aspect ratio is 5. The developed model reveals that the mixing length for a viscoelastic fluid may be by far larger than that for a Newtonian fluid. Moreover, the Taylor dispersion coefficient for electroosmotic flow of viscoelastic fluids, which its determination is a main part of the analysis, is found to be an increasing function of both the elasticity level and the EDL thickness. © 2015 American Institute of Chemical Engineers AIChE J, 61: 4533–4541, 2015     

Organocatalytic Enantioselective Synthesis of Polysubstituted Spirooxindoles using a Tandem Michael–Michael Reaction

A highly efficient stereoselective method for the synthesis of functionalized spirooxindole derivatives with four contiguous stereogenic centers, including two adjacent quaternary stereogenic centers, was realized through an organocatalytic tandem Michael–Michael reaction. By employing a quinidine‐derived thiourea organocatalyst, the reaction between (E)‐2‐cyano‐2‐(2‐oxo‐1‐tritylindolin‐3‐ylidene)acetates and (E)‐1‐alkyl‐6‐nitro‐hex‐2‐en‐1‐ones yields the desired spirooxindole products in good yields (up to 90%) and with excellent stereoselectivities (up to 95:5 dr and 98% ee).

     

Toward a computational multiresolution analysis for radial point interpolation meshless method

In this work, the application of Daubechies' scaling functions (DSFs) in computational engineering, particulary radial point interpolation meshless method (RPIM) in electromagnetic engineering, is studied. This analysis indicates some shortcomings of DSFs in computational engineering. In fact, the DSFs take the role of shape functions in RPIM, but they do not hold some general properties of shape functions. Modifying these shortcomings according to engineering requirements as time consumption rate, new scaling (shape) functions are derived, and testing them into two important classes of electromagnetic problems, that is, incident wave on dielectrics and scatterers, gives good agreement with exact solutions. Copyright © 2014 John Wiley & Sons, Ltd.     

A Novel Solution for Stochastic Dynamic Game of Water Allocation from a Reservoir Using Collocation Method

In this study, a continuous model of stochastic dynamic game for water allocation from a reservoir system was developed. The continuous random variable of inflow in the state transition function was replaced with a discrete approximant rather than using the mean of the random variable as is done in a continuous model of deterministic dynamic game. As a result, a new solution method was used to solve the stochastic model of game based on collocation method. The collocation method was introduced as an alternative to linear-quadratic (LQ) approximation methods to resolve a dynamic model of game. The collocation method is not limited to the first and second degree approximations, compared to LQ approximation, i.e. Ricatti equations. Furthermore, in spite of LQ related problems, consideration of the stochastic nature of game on the action variables in the collocation method would be possible. The proposed solution method was applied to the real case of reservoir operation, which typically requires considering the effect of uncertainty on decision variables. The results of the solution of the stochastic model of game are compared with the results of a deterministic solution of game, a classical stochastic dynamic programming model (e.g. Bayesian Stochastic Dynamic Programming model, BSDP), and a discrete stochastic dynamic game model (PSDNG). By comparing the results of alternative methods, it is shown that the proposed solution method of stochastic dynamic game is quite capable of providing appropriate reservoir operating policies.