Neural Network Based Approach for Developing the Enterprise Strategy

Modern enterprises work in highly dynamic environment. Thus, the developing of company strategy is of crucial importance. It determines the surviving of the enterprise and its evolution. Adapting the desired management goal in accordance with the environment changes is a complex problem. In the present paper, an approach for solving this problem is suggested. It is based on predictive control philosophy. The enterprise is modelled as a cybernetic system and the future plant response is predicted by a neural network model. The predictions are passed to an optimization routine, which attempts to minimize the quadratic performance criterion

Neural Network Based Optimal Control with Constraints

In the present paper the problems of the optimal control of systems when constraints are imposed on the control is considered. The optimality conditions are given in the form of Pontryagin’s maximum principle. The obtained piecewise linear function is approximated by using feedforward neural network. A numerical example is given

Catalytic VOCs elimination over copper and cerium oxide modified mesoporous SBA-15 silica

[EN] Copper and cerium oxide bi-component materials with different Cu/Ce ratio were prepared using ordered SBA-15 silica as a support and compared with their bulk analogs. The samples were characterized by nitrogen physisorption, XRD, UV-Vis, FTIR, XPS, Raman spectroscopy and TPR with hydrogen. Cyclohexanol conversion was used as a catalytic test to obtain more information for the surface properties of the supported materials. The catalytic properties of the samples were studied in VOCs oxidation using toluene and ethyl acetate as probe molecules. A strong effect of mesoporous silica support and samples composition on the formation of catalytic sites was established. (C) 2012 Elsevier B.V. All rights reserved.Financial support of Bulgarian Academy of Science and National Scientific Fond of Ministry of Education Projects DTK 02/64 and ДНTC/Киtай 01/8, financial support from DGICYT in Spain (Project CTQ-2009-14495) and bilateral project Bulgarian-Spain Inter-academic Exchange Agreement (Project 2009BG0002) are acknowledged.Tsoncheva, T.; Issa, G.; Blasco Lanzuela, T.; Dimitrov, M.; Popova, M.; Hernández Morejudo, S.; Kovacheva, D.... (2013). Catalytic VOCs elimination over copper and cerium oxide modified mesoporous SBA-15 silica. Applied Catalysis A General. 453:1-12. https://doi.org/10.1016/j.apcata.2012.12.007S11245

A Novel Multi‐Functional Thiophene‐Based Organic Cation as Passivation, Crystalline Orientation, and Organic Spacer Agent for Low‐Dimensional 3D/1D Perovskite Solar Cells

Recently, the mixed-dimensional (3D/2D or 3D/1D) perovskite solar cells using small organic spacers have attracted interest due to their outstanding long-term stability. Here, a new type of thiophene-based organic cation 2-(thiophene-2yl-)pyridine-1-ium iodide (ThPyI), which is used to fabricate mixed-dimensional 3D/1D perovskite solar cells, is presented. The ThPyI-based 1D perovskitoid is applied as a passivator on top of a 3D methyl ammonium lead iodide (MAPI) to fabricate surface-passivated 3D/1D perovskite films or added alone into the 3D perovskite precursor to generate bulk-passivated 3D MAPI. The 1D perovskitoid acts as a passivating agent at the grain boundaries of surface-passivated 3D/1D, which improves the power conversion efficiency (PCE) of the solar cells. Grazing incidence wide-angle X-ray scattering (GIWAXS) studies confirm that ThPyI triggers the preferential orientation of the bulk MAPI slabs, which is essential to enhance charge transport. Champion bulk-passivated 3D and surface-passivated 3D/1D devices yield 14.10% and 19.60% PCE, respectively. The bulk-passivated 3D offers favorable stability, with 84% PCE retained after 2000 h without encapsulation. This study brings a new perspective to the design of organic spacers having a different binding motif and a passivation strategy to mitigate the impact of defects in hybrid 3D/1D perovskite solar cells

Non-linear problems of heat and mass transfer with variable coefficients of diffusion and heat conductivity

info:eu-repo/semantics/publishe

of the National Academy of Sciences. NEURAL NETWORK BASED OPTIMAL CONTROL WITH CONSTRAINTS

[Линник,1962] Ю.В.Линник Метод наименьших квадратов и основы математико-статистической теории обработк

Facile Synthesized Cu–RGO and Ag–RGO Nanocomposites with Potential Biomedical Applications

In the present study, we report on the facile prepared nanocomposites of reduced graphene oxide RGO with Cu and Ag. The synthesis was performed through an environmentally friendly and easy method by simultaneous reduction in solutions containing Cu2+ or Ag+ and graphene oxide (GO) using zinc powder as a reducing agent in aqueous acidic media. The composites are characterized by powder X-ray diffraction, low-temperature nitrogen adsorption, X-ray photoelectron and FTIR and Raman spectroscopies, as well as Scanning and Transmission electron microscopies. The antibacterial activity of the composites was tested for Staphylococcus aureus, Escherichia coli and antifungal activity for Candida albicans. The cytotoxicity of the materials was studied towards two types of eukaryotic cells—MDCK II and A549 cell lines. The composites obtained consist of homogeneously distributed Cu and Ag nanoparticles on the surface of graphene sheets and manifest good antimicrobial activity and high cytotoxicity. The results clearly show that both metal–RGO composites can be successfully used as antimicrobial and anticancer agents

CO₂ Hydrogenation to Renewable Methane on Ni/Ru Modified ZSM-5 Zeolites: The Role of the Preparation Procedure

Mono- and bimetallic Ni- and Ru-modified micro-mesoporous ZSM-5 catalysts were prepared by wet impregnation. The influence of the Ni content, the addition of Ru and the sequence of the modification by two metals on the physicochemical properties of the catalysts were studied. They were characterized by X-ray powder diffraction (XRD), N2 physisorption, temperature-programmed reduction (TPR-TGA), TEM and XPS spectroscopy. Formation of finely dispersed nickel and/or ruthenium oxide species was observed on the external surface and in the pores of zeolite support. It was found that the peculiarity of the used zeolite structure and the modification procedure determine the type of formed metal oxides, their dispersion and reducibility. XPS study revealed that the surface became rich in nickel and poorer in ruthenium for bimetallic catalysts. Ni had higher dispersion in the presence of ruthenium, and TPR investigations also confirmed its facilitated reducibility. The studied catalysts were tested in CO2 hydrogenation to methane. 10Ni5RuZSM-5 material showed the highest activity and high selectivity for methane formation, reaching the equilibrium conversion and 100% selectivity at 400 °C. Stability and reusability of the latter catalyst show that it is appropriate for practical application

A novel multi-functional thiophene-based organic cation as passivation, crystalline orientation, and organic spacer agent for low-dimensional 3D/1D perovskite solar cells

Recently, the mixed-dimensional (3D/2D or 3D/1D) perovskite solar cellsusing small organic spacers have attracted interest due to their outstandinglong-term stability. Here, a new type of thiophene-based organic cation2-(thiophene-2yl-)pyridine-1-ium iodide (ThPyI), which is used to fabricatemixed-dimensional 3D/1D perovskite solar cells, is presented. TheThPyI-based 1D perovskitoid is applied as a passivator on top of a 3D methylammonium lead iodide (MAPI) to fabricate surface-passivated 3D/1Dperovskite films or added alone into the 3D perovskite precursor to generatebulk-passivated 3D MAPI. The 1D perovskitoid acts as a passivating agent atthe grain boundaries of surface-passivated 3D/1D, which improves the powerconversion efficiency (PCE) of the solar cells. Grazing incidence wide-angleX-ray scattering (GIWAXS) studies confirm that ThPyI triggers the preferentialorientation of the bulk MAPI slabs, which is essential to enhance chargetransport. Champion bulk-passivated 3D and surface-passivated 3D/1Ddevices yield 14.10% and 19.60% PCE, respectively. The bulk-passivated 3Doffers favorable stability, with 84% PCE retained after 2000 h withoutencapsulation. This study brings a new perspective to the design of organicspacers having a different binding motif and a passivation strategy to mitigatethe impact of defects in hybrid 3D/1D perovskite solar cells.A. Semerci, A. Buyruk, R. Hooijer, P. Mayer, D. Blätte, M. Günther, T. Bein,T. AmeriDepartment of Chemistry and Center for NanoScience (CeNS)Ludwig-Maximilians-Universität MünchenButenandtstrasse 5–13 (E), 81377 Munich, GermanyE-mail:tayebeh.ameri@ed.ac.ukS.EminMaterialsResearchLaboratoryUniversityofNovaGoricaVipavska13c,Ajdovšˇcina5270,SloveniaThe ORCID identification number(s) for the author(s) of this articlecan be found under https://doi.org/10.1002/adom.202300267© 2023 The Authors. Advanced Optical Materials published byWiley-VCH GmbH. This is an open access article under the terms of theCreative Commons Attribution-NonCommercial License, which permitsuse, distribution and reproduction in any medium, provided the originalwork is properly cited and is not used for commercial purposes.DOI: 10.1002/adom.2023002671. IntroductionDuring the last decade, 3D organic–inorganic halide perovskites (OIHPs) haveemerged as promising absorber materialsfor photovoltaic applications due to theirsuperior properties such as high absorp-tion coefficient, long diffusion length ofthe charge carriers, fast charge transport,and tunable bandgap. The 3D OIHPs havedemonstrated rapid increase in powerconversion efficiency (PCE) from 3.8% to25.2%.[1–9]On the other hand, their mod-erate intrinsic stability against moistureand heat still has been a concern with aview on possible commercialization.[10–14]Instability of the 3D methyl ammoniumlead iodide (MAPI) perovskite is assumedto be due to its crystalline structure. Ionicmigration is now well recognized to affectthe photovoltaic properties of perovskitesolar cells. Especially, the ionic migrationcauses the generation and displacement ofvacancies in perovskite materials. OIHPsare mixed ionic–electronic conductors withiodide ions as the majority of ionic carriers.D. KovachevaInstitute of General and Inorganic ChemistryBulgarian Academy of SciencesSofia 1113, BulgariaM. A. Reus, P. Müller-BuschbaumTUM School of Natural SciencesDepartment of PhysicsChair for Functional MaterialsTechnical University of MunichJames-Franck-Str. 1, 85748 Garching, GermanyN. F. HartmannAttocube systems AGNanoscale AnalyticsneaspecEglfinger Weg 2, 85540 Haar, GermanyS. Lotfi, J. P. HofmannSurface Science LaboratoryDepartment of Materials and Earth SciencesTechnical University of DarmstadtOtto-Berndt-Str. 3, 64287 Darmstadt, GermanyAdv. Optical Mater.2023,11, 23002672300267 (1 of 13)© 2023 The Authors. Advanced Optical Materials published by Wiley-VCH Gmb