A Model of Optimal Network Structure for Decentralized Nearest Neighbor Search

One of the approaches for the nearest neighbor search problem is to build a network which nodes correspond to the given set of indexed objects. In this case the search of the closest object can be thought as a search of a node in a network. A procedure in a network is called decentralized if it uses only local information about visited nodes and its neighbors. Networks, which structure allows efficient performing the nearest neighbour search by a decentralised search procedure started from any node, are of particular interest especially for pure distributed systems. Several algorithms that construct such networks have been proposed in literature. However, the following questions arise: "Are there network models in which decentralised search can be performed faster?"; "What are the optimal networks for the decentralised search?"; "What are their properties?". In this paper we partially give answers to these questions. We propose a mathematical programming model for the problem of determining an optimal network structure for decentralized nearest neighbor search. We have found an exact solution for a regular lattice of size 4x4 and heuristic solutions for sizes from 5x5 to 7x7. As a distance function we use L1 , L2 and L_inf metrics. We hope that our results and the proposed model will initiate study of optimal network structures for decentralised nearest neighbour search

Obtaining of Granulated Gypsum Anhydrite on the Basis of Technogenic Wastes of Chemical and Metallurgical Complex for Use in Portland Cement Production

The composition and properties of fluorine–anhydrite and steel–refining slag which are wastes of production of hydrogen fluoride and steel were determined. It is established that fluorine–anhydrite of the current output does not meet the requirements to materials for the production of Portland cement. Therefore to improve the technical and consumer properties of fluorine-anhydrite (for increasing the amount of CaSO4 ⋅2H2O and neutralization of H2SO4) the studies of its’ conditioning processes with steel– refining slag were carried out. It was found that the mass transfer coefficient of sulfuric acid through the capillary and the degree of its neutralization by slag depend on the dispersion of fluorine–anhydrite, its porosity and initial acidity. The most effective binding of sulfuric acid occurs with the introduction of slag in stoichiometric amounts, the size of fluorine–anhydrite granules up to 20 mm and a processing time of 60 minutes. After storage in air-humid conditions for 12 hours of fluorine–anhydrite treated with slag the strength of its granules, the amount of dihydrate gypsum and toxicological properties meet the requirements. Keywords: techno–gypsum, refining slag, neutralization, conditioning, gypsum stone, Portland cemen

The Composition and Properties of the Tailings of Quartzite Enrichment of “Gora Karaul’naya” Deposit

The JSC “DINUR” use enriched quartzite from the “Gora Karaul’naya” deposit in the production of dinas refractories. The tailings of quartzite enrichment are stored in the dump, not used, and thereby pollute the environment. Chemical, mineral and grain composition, physical, mechanical and technological properties of samples of quartzite tailings of the current output and selected from the dump are determined in this study. The tailings of current output contain less oxides of aluminum, iron and calcium and alkalis compared to the dump tailings. Their mineral composition is mainly represented by quartz as well as impurities of muscovite, hematite, magnetite, chlorite, shungite, zircon, rutile, pyrite with a total content of up to 3 %. The dump quartzite tailings contain particles less than 5 mm in size with a predominance of dust–like fractions (less than 0.16 mm). As to the grain composition, content of dust and clay particles, clay lumps and impurities tailings of the current output meets the requirements of Russian Standard no. 31424 (for the sand from sifting of crushing solid stone), belong to the class II, group of large sands; dump tailings belong to class I and the group of medium sands. Up to 30 % of the particles are plate– and needle–shaped. The features of changes in chemical composition, bulk density, content of dust–like, clay and organic impurities depending on the size of tailings fractions are considered. The possibility of using of tailings of quartzite enrichment as sand for construction works and fine fractions of tailings as molding material in foundry and granular loading in pressure and non−pressure filters for water purification is shown. Keywords: quartz, tailings, composition, properties, us

Technogenic Mineral Raw Materials for the Production of Refractories and Ceramics

Chemical–mineral and material–genetic classifications of technogenic mineral raw materials including up to 36 polyphase groups of materials that form the basis of secondary resources suitable for the production of refractories and ceramics after additional processing are proposed. It is shown that technogenic materials of the Urals are cheap multifunctional raw materials and can be used in the production of magnesia-silicate ceramics, carbon– and zirconium–containing high-alumina refractories and cements. Keywords: classification, secondary mineral resources, composition, recycling, refractories, ceramic

Harmonization of Income Data in EU-SILC: Update of GESIS Paper 2015/18

This report is intended to provide an overview of income measures employed in the EU-SILC and to inform on procedures which can be employed to harmonize these data both for comparisons over time and between countries. Each subsection provides a short overview over a topic or meth-od and contains example code for Stata and SPSS which can be used to implement the described procedures. Alongside this report syntax files as well as a data files for both SPSS and Stata are delivered which include the code provided here as well auxiliary country level data drawn from the Eurostat database1. In this updated version, an extended appendix is included that explains how to generate and replicate these files in more detail

Detecting synchronization of self-sustained oscillators by external driving with varying frequency

We propose a method for detecting the presence of synchronization of self-sustained oscillator by external driving with linearly varying frequency. The method is based on a continuous wavelet transform of the signals of self-sustained oscillator and external force and allows one to distinguish the case of true synchronization from the case of spurious synchronization caused by linear mixing of the signals. We apply the method to driven van der Pol oscillator and to experimental data of human heart rate variability and respiration.Comment: 9 pages, 7 figure

Confinement-controlled Water Engenders High Energy Density Electrochemical-double-layer Capacitance

The renewable energy sector critically needs low-cost and environmentally neutral energy storage solutions throughout the entire device life cycle. However, the limited performance of standard water-based electrochemical systems prevents their use in certain applications. Meanwhile, recent fundamental studies revealed dielectric anomalies of water near solid-liquid interfaces of carbon-based nanomaterials. In contrast to the bulk water properties, these anomalies of water under nano-confinement and in the presence of electric fields have not yet been understood and used. Here, we experimentally study the ability of the interfacial water layer to engender and store charge in electrochemical double-layer capacitance. We demonstrate the first prototype of a water-only membrane-electrode assembly. The prototype exhibits characteristics comparable to existing batteries and supercapacitors without using electrolytes as ionic carriers. The results provide the impetus for the development of high-energy-density electrochemical double-layer capacitors and open up other avenues for ecologically-neutral batteries, fuel cells, and nanofluidic devices