6,692 research outputs found
Single and Multi-Dimensional Optimal Auctions - A Network Approach
This paper highlights connections between the discrete and continuous approaches to optimal auction design with single and multi-dimensional types. We provide an interpretaion of an optimal auction design problem in terms of a linear program that is an instance of a parametric shortest path problem on a lattice. We also solve some cases explicitly in the discrete framework.Auctions, Networks, Linear Programming
Stoichiography: New Ways Determining Chemical Composition and Real Structure of Materials
The principles of stoichiography and novel reference-free methods of molecular and phase analysis for complex unknown mixtures are considered. The stoichiography can be inferred from stoichiometry of mass
transfer of unsteady homo- and heterophase processes and joins both operations: separation of mixture by
means of chromatography, electromigration, dissolution or others and determination of stoichiometry of a
substance flow with time. The stoichiography allows a chemical compound to be determined by its primary
property, namely, by stoichiometry of elemental composition. Stoichiograms provided a basis for such type
of information. They are time variances of molar ratio for mass transfer rates of chemical elements from
multielement substances. Invariancy to concentration and temperature of solvents, hydrodynamic regime is
a fundamental property of the stoichiograms in the case of individual compounds. Therefore the stoichiograms are kept constant and are equal to formula stoichiometric coefficients of the individual compound. Theory and methodology of new stoichographic methods, differential dissolution and ion-chromato-stoichiography are presented. New equipment, stoichiograph, and a new procedure of differential dissolution, stoichiographic titration, are discussed here in details. Applications of differential dissolution to analyze multielement and polyphase crystalline and amorphous samples are given.
***The author devotes this paper to memory of his teacher, Professor O. A. Songina, an outstanding scientist, who began to develop fundamental ideas concerning chemical and electrochemical methods of the phase analysis. The essence of this paper was reported on International Conference of Analytical Chemistry, which was organized on the occasion of the 100th Birthday of Professor O. A. Songina on May 22-25th, 2001, in Almaty, Kazakhstan
Variability of magnetic field spectra in the Earth's magnetotail
We investigate the variability of magnetic fluctuation spectra below 1 Hz in the Earth's plasma sheet using specially selected long observation intervals by Geotail spacecraft. The spectra can be generally described by a negative power law with two kinks. The range between kinks ~0.02–0.2 Hz has the most stable power law index ~2.4–2.6. Indices at the lower and the higher frequencies are more variable and generally increase with power of fluctuations. In the sub-second range fluctuations are strongly localized and indices are closer to 3. At the lower-frequency end indices are about 1.5. The lower kink is usually well defined on average spectra and its frequency tends to increase with activity. Combination of spectrum index α and fractal dimension δ is expected to follow the Berry relation α+2δ=5, but actually is ~5.5
Hybrid e-rehabilitation services: SMART-system for remote support of rehabilitation activities and services
One of the most effective solutions in medical rehabilitation assistance is remote patient / person-centered rehabilitation. Rehabilitation also needs effective methods for the “Physical therapist – Patient – Multidisciplinary team” system, including the statistical processing of large volumes of data. Therefore, along with the traditional means of rehabilitation, as part of the “Transdisciplinary intelligent information and analytical system for the rehabilitation processes support in a pandemic (TISP)” in this paper, we introduce and define: the basic concepts of the new hybrid e-rehabilitation notion and its fundamental foundations; the formalization concept of the new Smart-system for remote support of rehabilitation activities and services; and the methodological foundations for the use of services (UkrVectores and vHealth) of the remote Patient / Person-centered Smart-system. The software implementation of the services of the Smart-system has been developed
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