Effect of Utility Function Curvature of Young’s Bargaining Method on the Design of WDNs

The optimal design of a water distribution network is a simulation-optimization task that should consider conflicts between different groups of stakeholders directly or indirectly. Investors and consumers are two groups of stakeholders with conflicting goals. Young’s bargaining method is a decision tool based on game theory that can help decision-makers to select one of the design alternatives by considering utilities of stakeholders. In this paper, the optimal design of two benchmark network problems (Two-loop and Hanoi networks) is considered with minimization of design cost and maximization of system efficiency, with respect to increasing hydraulic pressure. In this regard, decision alternatives are first determined by using a multi-objective, fast, messy genetic algorithm (MOFMGA). Young’s bargaining method is then applied with different combinations of utility functions of stakeholders. Results show that the use of the same utility functions for both stakeholders improves 63.23% and 24.47% of investor goals and 79.08% and 45.69% of consumer goals compared to the worst possible alternatives in the Two-loop and Hanoi networks, respectively. Moreover, both investor and consumer goals improve 6.19% and 7.14% in the Two-loop and 22.73% and 6.07% in the Hanoi network using a more concave utility function whose emphasis is on stakeholder utility, respectively.     

New exponential bounds and approximations for the computation of error probability in fading channels

We present new exponential bounds for the Gaussian Q function (one- and two-dimensional) and its inverse, and for M-ary phase-shift-keying (MPSK), M-ary differential phase-shift-keying (MDPSK) error probabilities over additive white Gaussian noise channels. More precisely, the new bounds are in the form of the sum of exponential functions that, in the limit, approach the exact value. Then, a quite accurate and simple approximate expression given by the sum of two exponential functions is reported. The results are applied to the general problem of evaluating the average error probability in fading channels. Some examples of applications are also presented for the computation of the pairwise error probability of space-time codes and the average error probability of MPSK and MDPSK in fading channels.     

Bounds and approximations for optimum combining of signals in the presence of multiple cochannel interferers and thermal noise

We derive an upper bound and investigate some approximations on the symbol error probability (SEP) for coherent detection of M-ary phase-shift keying, using an array of antennas with optimum combining in wireless systems in the presence of multiple uncorrelated equal-power cochannel interferers and thermal noise in a Rayleigh fading environment. Our results are general and valid for an arbitrary number of antenna elements as well as an arbitrary number of interferers. In particular, the exact SEP is derived for an arbitrary number of antennas and interferers; the computational complexity of the exact solution depends on the minimum number of antennas and interferers. Moreover, closed-form approximations are provided for the cases of dual optimum combining with an arbitrary number of interferers, and of two interferers with an arbitrary number of antenna elements. We show that our bounds and approximations are close to Monte Carlo simulation results for all cases considered in this paper.     

Spatial and temporal equalization for broadband wireless indoornetworks at millimeter waves

The combined use of adaptive antennas and decision feedback equalization (DFE) is analyzed in a realistic propagation scenario at millimeter waves, taking the direction of arrivals (DOA's) of the received paths into account. The joint antennas and DFE scheme, with one forward filter for each antenna and a single feedback filter (FBF), can be viewed as a spatial and temporal DFE (ST-DFE). The performance of this solution is compared with the cascade of adaptive antenna used for beamforming and DFE. It is found that ST-DFE achieves better performance since it combines the beamforming capability of the antenna array with the equalization properties of the DFE, with great advantages especially when rays arrive from similar angles. The mean square error (MSE) is analytically derived for infinitely long filters in a quasi-static environment with multiple rays having different DOAs, and compared (for the two-path model) with simulation results assuming filters with a small number of taps. Finally, service availability through coverage evaluation is developed and compared with that of a coded-orthogonal frequency division multiplexing (C-OFDM) system     

Simple reconfigurable low-density parity-check codes

Low-density parity-check codes (LDPCC) have been recently investigated as a possible solution for high data rate applications, for both space and terrestrial wireless communications. A main issue is the research of low complexity encoding and decoding schemes. In this letter we present a class of reconfigurable LDPCC characterized by low encoding and decoding complexity: we call them generalized irregular repeat-accumulate (GeIRA) codes.     

Magnetic Nanoparticle-Supported Cu–NHC Complex as an Efficient and Recoverable Catalyst for Nitrile Hydration

Magnetic nanoparticles supported N-heterocyclic carbene–Cu complex was prepared and authenticated by FT-IR, SEM, EDX, VSM, powder-XRD. The catalytic activity of these magnetically retrievable NPs was investigated for hydration of nitriles as the simplest route for the synthesis of amides in an atom-economical manner. A wide range of nitriles containing various functional groups such as olefin, aldehyde, nitro, carboxylic acid was examined in this transformation to generate their corresponding amides in the aqueous medium. The immobilized catalyst was easily recovered using an external magnet and reused for six times without significant loss of its catalytic activity.

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Synthesis of cobalt-orthotitanate inverse spinel nano particles via a novel low temperature solvothermal method: structural,opto-electronical,morphological, surface characterization and photo-catalytical application in mineralization of Remazol Red RB 133

Synthesis of single phase cobalt-orthotitanate inverse spinel nano particles is reported for the first time via a novel solvothermal method at low calcination temperature at 400?°C. The pure phase cobalt-orthotitanate spinel nano particles were prepared using cobalt nitrate and titanium tetraisopropoxide (1:1 molar ratio) as cobalt and titanium sources. The synthesised Co₂TiO₄ nanoparticles were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), fourier transform infrared spectroscopy, energy dispersive X-ray spectroscopy, surface area analyses (Brauner–Emmett–Teller) (BET) and UV–Vis diffuse reflectance spectroscopy. The XRD results proved the formation of a single phase cobalt-orthotitanate (Co₂TiO₄) nanoparticles by calcination temperature of 400?°C. The FE-SEM results showed that nano particles possess a uniform spherical morphology with an average size of 51 nm. Porosity and specific surface area of cobalt-orthotitanate nano particles was measured by nitrogen adsorption using BET and the results showed surface area of 44.47 m²/g. DRS results showed an optical band gap value of 1.802 eV for cobalt-orthotitanate nano powder. An excellent performance as a nano photo-catalyst toward the degradation of Remazol Red RB 133 (RR133) as a single azo textile dye with excellent efficiency. Mineralization of RR133 by highly active cobalt-orthotitanate nano-catalyst coated on glass surface was applied and 97% TOC removal was observed. This is due to high electron–hole charge separation and high surface area of nano-catalyst.     

The study on structural properties and tensile strength of reared silkworm cocoon

Silkworm cocoon is a natural composite with laminated structure in which is made of silk fibers conglutinated by sericin. Recently, the identification of silkworm cocoon composite structure as a nonwoven complex structure and its properties are attracted by several researches. In this study, the structure and morphology of reared silkworm cocoon as well as its mechanical properties have been studied. Silkworm cocoon structural features, such as fiber diameter, porosity, fiber length, number of fiber intersection, the number of pores, and fiber orientation were evaluated for outermost and innermost layers in three sections using image processing method. Also the mechanical properties such as tensile strength, initial modulus, and toughness of silkworm cocoon in the three sections of cocoon head, middle, and tail were measured. The structural analysis of silkworm cocoon shows that the innermost layer has finer fibers with a lower density structure compared to the outermost layer. Fiber orientation in cocoon middle section is more than the head and tail sections. Also the results of mechanical properties of silkworm cocoon show that tensile strength, initial modulus, and toughness are significantly different in three sections of cocoon in which the cocoon middle section exhibits a higher tensile strength and initial modulus than the head and tail sections.     

Potential Release of Metals from Tailings and Soil at the Hamekasi Iron Mine,Hamadan, Iran

This study focused on acid neutralization reactions and the effects of water composition on the release and mobility of metals from mine tailings. The aims of this study were to: investigate leaching of metals from neutral mine tailings, determine the factors responsible for metal leaching, and investigate potential metal filtering by the soil. Tailings and soil samples were collected from an iron mine and analyzed. Equilibrium thermodynamic data and metal fractionation were then used to predict precipitation/dissolution of minerals and ion adsorption/desorption. Three column experiments were designed. The first column was filled with tailings, while the second column contained tailings above a layer of soil; both were leached with distilled water as rainfall. The third column was packed with soil and percolated with synthetic groundwater. The results indicated that iron (Fe) and zinc (Zn) mobility are mainly controlled by precipitation–dissolution mechanisms, while sorption onto oxides and carbonates limit the mobility of copper (Cu) and nickel (Ni). Cadmium (Cd) and manganese (Mn) mobility are affected by both mechanisms. Water discharging from column 3 (soil washed with groundwater) contained high concentrations of dissolved metals, indicating that water composition played an important role in metal mobility. Buffering minerals like carbonates and hornblende, chlorite, and albite decreased acid generation.