On partial shadowing of complete pseudo-orbits

In recent years many new definitions of shadowing, using a notion of ergodic (or average) pseudo-orbit were introduced. While, under the assumption of chain mixing, average pseudo-orbit usually can be equivalently replaced by pseudo-orbit in these definitions of shadowing, it is not completely clear when these shadowing properties (i.e. approximation of a pseudo-orbit by a real orbit on a sufficiently large set of indices) can or cannot occur. In this paper we analyze necessary and sufficient conditions for shadowing over a set with positive density (or syndetic). While we do not provide full characterization, a few relations to standard notions from topological dynamics are obtained.     

On the Calculus of Limiting Subjets on Riemannian Manifolds

In this paper fuzzy calculus rules for subjets of order two on finite dimensional Riemannian manifolds are obtained. Then a second order singular subjet derived from a sequence of efficient subsets of symmetric matrices is introduced. Employing fuzzy calculus rules for subjets of order two and various qualification assumptions based on a second order singular subjet, calculus rules for limiting subjets on a finite dimensional Riemannian manifold are obtianed.     

Projection Method Approach for General Regularized Non-convex Variational Inequalities

In this paper, we investigate or analyze non-convex variational inequalities and general non-convex variational inequalities. Two new classes of non-convex variational inequalities, named regularized non-convex variational inequalities and general regularized non-convex variational inequalities, are introduced, and the equivalence between these two classes of non-convex variational inequalities and the fixed point problems are established. A projection iterative method to approximate the solutions of general regularized non-convex variational inequalities is suggested. Meanwhile, the existence and uniqueness of solution for general regularized non-convex variational inequalities is proved, and the convergence analysis of the proposed iterative algorithm under certain conditions is studied.     

A hybrid metaheuritic technique developed for hourly load forecasting

Electricity load forecasting has become one of the most functioning tools in energy efficiency and load management and utility companies which has been made very complex due to deregulation. Due to the importance of providing a secure and economic electricty for the consumers, having a reliable and robust enough forecast engine in short‐term load management is very needful. Fuzzy inference system is one of primal branches of Artificial Intelligence techniques which has been widely used for different applications of decision making in complex systems. This paper aims to develop a Fuzzy inference system as a main forecast engine for Short term Load Forecasting (STLF) of a city in Iran. However, the optimization of this platform for this special case remains a basic problem. Hence, to address this issue, the Radial Movement Optimization (RMO) technique is proposed to optimize the whole Fuzzy platform. To support this idea, the accuracy of the proposed model is analyzed using MAPE index and an average error of 1.38% is obtained for the forecast load demand which represents the reliability of the proposed method. Finally, results achieved by this method, demonstrate that an adaptive two‐stage hybrid system consisting of Fuzzy & RMO can be an accurate and robust enough choice for STLF problems. © 2016 Wiley Periodicals, Inc. Complexity 21: 521–532, 2016     

Day‐ahead price forecasting based on hybrid prediction model

Short‐Term Price Forecast is a key issue for operation of both regulated power systems and electricity markets. Energy price forecast is the key information for generating companies to prepare their bids in the electricity markets. However, this forecasting problem is complex due to nonlinear, nonstationary, and time variant behavior of electricity price time series. So, in this article, the forecast model includes wavelet transform, autoregressive integrated moving average, and radial basis function neural networks (RBFN) is presented. Also, an intelligent algorithm is applied to optimize the RBFN structure, which adapts it to the specified training set, reduce computational complexity and avoids over fitting. Effectiveness of the proposed method is applied for price forecasting of electricity market of mainland Spain and its results are compared with the results of several other price forecast methods. These comparisons confirm the validity of the developed approach. © 2016 Wiley Periodicals, Inc. Complexity 21: 156–164, 2016     

On the Recollements of Functor Categories

This paper is devoted to the study of recollements of functor categories in different levels. In the first part of the paper, we start with a small category \(\mathcal {S}\) and a maximal object s of \(\mathcal {S}\) and construct a recollement of \(\text {Mod-}\mathcal {S}\) in terms of \(\text {Mod-End}_{\mathcal {S}}(s)\) and \(\text {Mod-}(\mathcal {S}\setminus \{s\})\) in four different levels. In case \(\mathcal {S}\) is a finite directed category, by iterating this argument, we get chains of recollements having some interesting applications. In the second part, we start with a recollement of rings and construct a recollement of their path rings, with respect to a finite quiver. Third part of the paper presents some applications, including recollements of triangular matrix rings, an example of a recollement in Gorenstein derived level and recollements of derived categories of N-complexes.     

On the oriented chromatic number of graphs with given excess

The excess of a graph G is defined as the minimum number of edges that must be deleted from G in order to get a forest. We prove that every graph with excess at most k has chromatic number at most and that this bound is tight. Moreover, we prove that the oriented chromatic number of any graph with excess k is at most k+3, except for graphs having excess 1 and containing a directed cycle on 5 vertices which have oriented chromatic number 5. This bound is tight for k?4.     

On Zero Sets in the Dirichlet Space

We study the zero sets of functions in the Dirichlet space. Using Carleson??s formula for the Dirichlet integral, we obtain some new families of zero sets. We also show that any closed subset of $E \subset \mathbb {T}$ with logarithmic capacity zero is the set of accumulation points of the zeros of a function in the Dirichlet space. The zeros satisfy a growth restriction which depends on E.     

Fragmentation reaction of highly sterically hindered TsiSiPhCl2 with some alcoholic sodium alkoxides

TsiSiPhCl₂(1) was treated with boiling NaOEt/EtOH to give the fragmentation product of the type (Me₃Si)₂CHSiPh(OEt)₂. Treatment of 1 with various alkoxides NaOR/ROH (R = n-Pr, n-Bu, iso-Bu, 2-Bu, amyl, iso-amyl, 2-amyl, CH₂Ph) gave Me₃SiCH₂SiPh(OR)₂ rather than the expected (Me₃Si)₂CHSiPh(OR)₂. Study of the products showed that alkoxides as a nucleophile can not attack the silicon center bearing the (Me₃Si)₃C– group because of steric hindrance. It is suggested that the reaction proceeds through an elimination, analogous to E2 eliminations of alkyl halides, involving synchronous attack of RO⁻ at a Me₃Si group, liberation of X⁻, and formation of (Me₃Si)₂C=SiPhCl. The reaction of NaOEt/EtOH with dichloride 1 takes different route from other alkoxides.     

Preparation of Ni/poly(1,5-diaminonaphthalene)-modified carbon paste electrode; application in electrocatalytic oxidation of formaldehyde for fuel cells

This paper deals with electrochemical oxidation of formaldehyde in alkaline solution with a new electrocatalytic system composed of carbon paste electrode coated with poly(1,5-diaminonaphthalene) (P-1,5-DAN) film containing incorporated Ni(II)/Ni(III) redox ions. The modifier layer of (P-1,5-DAN-Ni)(OH)₂ at the electrode surface acts as a catalyst for the oxidation of formaldehyde in 0.1-M NaOH solution. Cyclic voltammetric and chronoamperometric experiments showed that the formaldehyde can be oxidized at the surface of Ni/P-1,5-DAN-modified carbon paste electrode. In cyclic voltammetry studies, the peak current of the oxidation of nickel hydroxide in the presence of formaldehyde increases and is followed by a decrease in the corresponding cathodic current. The rate constant (k) for the chemical reaction between the formaldehyde and nickel hydroxide has been evaluated by chronoamperometry method. This polymeric-modified electrode can oxidize the formaldehyde with high current density (over 7 mA cm⁻²). Thus, it can be a candidate as an anode for fuel cell applications.