The theory of organisation: a mathematical treatment of processing structures

2011 ◽  
pp. 97-112
Author(s):  
H. von Issendorff
Keyword(s):  
Mathematical Treatment

Sustainable Regional Economic Development: Analysis and Management Methods

2020 ◽  
Vol 26 (1) ◽  
pp. 23-34
Author(s):  
B. M. Grinchel’ ◽  
E. A. Nazarova
Keyword(s):  
Economic Development ◽  
Mathematical Treatment ◽  
Mathematical Tool ◽  
Russian Regions ◽  
Regional Economic ◽  
Management Scheme ◽  
Progressive Growth ◽  
Sustainable Regional Development ◽  
High Level ◽  
Development Analysis

The presented study examines methods for analyzing and managing sustainable economic development of Russian regions and possible criteria for assessing and improving sustainability.Aim. The study aims to provide a theoretical and empirical justification for the use of regional competitive attractiveness assessment to manage economic development and improve its sustainability.Tasks. Based on the measurement and analysis of economic competitive attractiveness indicators and their mathematical treatment, the authors assess the sustainability of development of Russian regions in 2013–2017 and the causes of deviations from progressive growth.Methods. This study proposes a mathematical tool for measuring the sustainability of Russian regions by assessing their competitive attractiveness and develops a typology of sustainability in the mathematical space of two variables.Results. Methods for analyzing and managing the sustainability of economic development of Russian regions under the influence of political and economic challenges and risks are proposed. The level and dynamics of regional competitive attractiveness are taken as a criterion of sustainability of economic development. The authors provide methods and indicators for assessing economic competitive attractiveness and criteria for measuring the sustainability of development, which allow them to draw conclusions about the reaction of different regions to the challenges and risks of development in 2013–2017. The study proposes a management scheme for sustainable regional development with a focus on the comprehensive improvement of regional economic competitive attractiveness and potential ways to improve it, including training of municipal and regional managers in crisis management associated with economic and political challenges and risks.Conclusions. Based on the proposed criterion of economic development sustainability and assessment of the competitive attractiveness of regions and their rankings, it is shown that in 2013–2017 45 out of 83 regions were developing sustainably; by 2017, 19 regions out of the 32 that suffered losses in the competitive attractiveness level and rankings in 2015–2016 have managed to restore the sustainability of economic development and their rankings. This study proves that regions with a high level of economic competitive attractiveness show increased sustainability of development.

scholarly journals Instrumental Odour Monitoring System Classification Performance Optimization by Analysis of Different Pattern-Recognition and Feature Extraction Techniques

Sensors ◽  
2020 ◽  
Vol 21 (1) ◽  
pp. 114
Author(s):  
Tiziano Zarra ◽  
Mark Gino K. Galang ◽  
Florencio C. Ballesteros ◽  
Vincenzo Belgiorno ◽  
Vincenzo Naddeo
Keyword(s):  
Pattern Recognition ◽  
Feature Extraction ◽  
Performance Optimization ◽  
Industrial Plant ◽  
Mathematical Treatment ◽  
Extraction Techniques ◽  
Peak Period ◽  
Linear Discriminant ◽  
Artificial Neural

Instrumental odour monitoring systems (IOMS) are intelligent electronic sensing tools for which the primary application is the generation of odour metrics that are indicators of odour as perceived by human observers. The quality of the odour sensor signal, the mathematical treatment of the acquired data, and the validation of the correlation of the odour metric are key topics to control in order to ensure a robust and reliable measurement. The research presents and discusses the use of different pattern recognition and feature extraction techniques in the elaboration and effectiveness of the odour classification monitoring model (OCMM). The effect of the rise, intermediate, and peak period from the original response curve, in collaboration with Linear Discriminant Analysis (LDA) and Artificial Neural Networks (ANN) as a pattern recognition algorithm, were investigated. Laboratory analyses were performed with real odour samples collected in a complex industrial plant, using an advanced smart IOMS. The results demonstrate the influence of the choice of method on the quality of the OCMM produced. The peak period in combination with the Artificial Neural Network (ANN) highlighted the best combination on the basis of high classification rates. The paper provides information to develop a solution to optimize the performance of IOMS.

Inverse Ostwald Ripening and Self-Organization of Nanoclusters due to Ion Irradiation

2000 ◽  
Vol 647 ◽  
Author(s):  
K.-H. Heinig ◽  
B. Schmidt ◽  
M. Strobel ◽  
H. Bernas
Keyword(s):  
Phase Separation ◽  
Ion Implantation ◽  
Ostwald Ripening ◽  
Ion Irradiation ◽  
Experimental Studies ◽  
Self Organization ◽  
Mathematical Treatment ◽  
Thermodynamical Equilibrium ◽  
Unusual Behavior ◽  
Thermally Activated

AbstractUnder ion irradiation collisional mixing competes with phase separation if the irradiated solid consists of immiscible components. If a component is a chemical compound, there is another competition between the collisional forced chemical dissociation of the compound and its thermally activated re-formation. Especially at interfaces between immiscible components, irradiation processes far from thermodynamical equilibrium may lead to new phenomena. If the formation of nanoclusters (NCs) occurs during ion implantation, the phase separation caused by ion implantation induced supersaturation can be superimposed by phenomena caused by collisional mixing. In this contribution it will be studied how collisional mixing during high-fluence ion implantation affects NC synthesis and how ion irradiation through a layer of NCs modifies their size and size distribution. Inverse Ostwald ripening of NCs will be predicted theoretically and by kinetic lattice Monte-Carlo simulations. The mathematical treatment of the competition between irradiation-induced detachment of atoms from clusters and their thermally activated diffusion leads to a Gibbs-Thomson relation with modified parameters. The predictions have been confirmed by experimental studies of the evolution of Au NCs in SiO2 irradiated by MeV ions. The unusual behavior results from an effective negative capillary length, which will be shown to be the reason for inverse Ostwald ripening. Another new phenomenon to be addressed is self-organization of NCs in a d-layer parallel to the Si/SiO2 interface. Such d-layers were found when the damage level at the interface was of the order of 1-3 dpa. It will be discussed that the origin of the d-layer of NCs can be assigned to two different mechanisms: (i) The negative interface energy due to collisional mixing gives rise to the formation of tiny clusters of substrate material in front of the interface, which promotes heteronucleation of the implanted impurities. (ii) Collisional mixing in the SiO2produces diffusing oxygen, which may be consumed by the Si/SiO2 interface. A thin layer parallel to the interface becomes denuded of diffusing oxygen, which results in a strong pile up of Si excess. This Si excess promotes heteronucleation too. Independent of the dominating mechanism of self-organization of a d-layer of NCs, its location in SiO2 close to the SiO2/Si interface makes it interesting for non-volatile memory application.

Rotational and Quasiviscous Cold Flow Models for Axisymmetric Hybrid Propellant Chambers

2010 ◽  
Vol 132 (10) ◽  
Author(s):  
Joseph Majdalani ◽  
Michel Akiki
Keyword(s):  
Rocket Engine ◽  
Navier Stokes ◽  
Mathematical Treatment ◽  
Hybrid Rocket ◽  
Mean Flow ◽  
Viscous Effects ◽  
Navier Stokes Equation ◽  
Flow Models ◽  
Hybrid Rocket Engine ◽  
Wall Injection

In this work, we present two simple mean flow solutions that mimic the bulk gas motion inside a full-length, cylindrical hybrid rocket engine. Two distinct methods are used. The first is based on steady, axisymmetric, rotational, and incompressible flow conditions. It leads to an Eulerian solution that observes the normal sidewall mass injection condition while assuming a sinusoidal injection profile at the head end wall. The second approach constitutes a slight improvement over the first in its inclusion of viscous effects. At the outset, a first order viscous approximation is constructed using regular perturbations in the reciprocal of the wall injection Reynolds number. The asymptotic approximation is derived from a general similarity reduced Navier–Stokes equation for a viscous tube with regressing porous walls. It is then compared and shown to agree remarkably well with two existing solutions. The resulting formulations enable us to model the streamtubes observed in conventional hybrid engines in which the parallel motion of gaseous oxidizer is coupled with the cross-streamwise (i.e., sidewall) addition of solid fuel. Furthermore, estimates for pressure, velocity, and vorticity distributions in the simulated engine are provided in closed form. Our idealized hybrid engine is modeled as a porous circular-port chamber with head end injection. The mathematical treatment is based on a standard similarity approach that is tailored to permit sinusoidal injection at the head end.

An appraisal of numerical integration methods as applied to strong-motion data

1943 ◽  
Vol 33 (1) ◽  
pp. 21-60
Author(s):  
Frank Neumann
Keyword(s):  
Numerical Integration ◽  
Fundamental Equation ◽  
Shaking Table ◽  
Mathematical Treatment ◽  
Torsion Pendulum ◽  
Massachusetts Institute Of Technology ◽  
Shaking Table Tests ◽  
Complex Type ◽  
Double Integration ◽  
Table Motion

Abstract Summary Accuracy of displacement curves computed from accelerograph records by numerical double integration.—The following results were obtained from Coast and Geodetic Survey accelerograph records in shaking-table tests made at the Massachusetts Institute of Technology: Accelerograph performance.—The preceding paragraphs show that the pivot type of accelerometer now in use is satisfactory from the engineering viewpoint and that wave forms in terms of displacement can be satisfactorily computed for all but the longer-period waves. In transferring from the quadrifilar type of pendulum suspension to the pivot type to obtain a sturdier and more readily adjustable instrument, some sacrifice was made in accuracy of performance, but it is not serious. Although the pivot suspensions embody the highest quality of workmanship, they nevertheless undergo (when recording an earthquake) a certain amount of minute shifting, and this is greatly amplified in the double-integration process. This necessitates a high standard of servicing, and some adjusting in the mathematical treatment. The present drum speed of 1 cm/sec. seems satisfactory enough for the present. Any expected increase in the accuracy of computed displacements through opening up the time scale would, at the present time, be nullified by errors resulting from pendulum instability. A more immediate advantage would be greater ease in disentangling overlapping curves and extrapolating those which go off the sheet entirely. Reduction of accelerometer sensitivity solves this problem, which in practice is serious. Errors due to imperfections in the uniformity of the paper speed are of secondary importance. A test with one accelerometer recording a 45° component of the true table motion indicated that accelerographs correctly record the components of an impressed motion according to theoretical expectations, but obviously within the limits of normal instrumental performance. Numerical integration.—The shaking-table tests prove the validity of the basis on which axis adjustments are made when one is double-integrating an accelerograph record to obtain displacement. All shaking-table motions were computed from the recorded acceleration (or seismograph) records without advance knowledge of the table motion, and no preliminary tests were made to investigate possible sources of error. They demonstrated that even permanent displacements can be detected under favorable conditions; but with most accelerograph records this is problematical. In the accelerometer tests a systematic error was found to be due to heat distortion of the accelerogram in the lantern enlargement process. After the tests, a specially designed mechanical enlarging apparatus eliminated this and incorporated many other practical advantages. With respect to the more complex type of shaking-table accelerograph record, it was found that a time increment five times larger than the 1/30 second actually used would have given practically the same result in computation of the shaking-table displacement. This means that the time employed on the summation processes could safely have been reduced to one-fifth that required for the smaller increment. Caution is necessary, however, if the velocity curve is to be used for period investigations or other special purposes, as the increment must be small enough to outline correctly all important waves. Time increments between 0.07 and 0.15 second would appear to serve satisfactorily for active types of accelerograms. The effect of omitting the first two terms of the fundamental equation of pendulum motion was determined for a complex type of shaking-table motion and was found to be rather insignificant. Current practice assumes that an accelerometer registers true acceleration for very rapid motions as well as for the slower ones, but there are limitations. The effect would be even less if the accelerometer pendulum period should be shortened, a step which would also effect a desirable decrease in sensitivity. The time required to process accelerograms is not prohibitive. The actual summation processes require less time than enlarging and scaling the acceleration curves and constructing the computed curves, but a considerable amount of additional work is usually involved because of adjustments and recomputations made necessary by accelerometer-pendulum zero shifts. Displacement with a torsion-pendulum analyzer.—An actual earthquake accelerograph record was used to test the practicability of determining displacement by making an experimental torsion pendulum simulate the response of a long-period seismograph pendulum. A comparison between the pendulum curve and the displacement computed by double-integrating the accelerograph record revealed a difference which was only half the smallest displacement error found in the M.I.T. shaking-table tests. Pendulum results, however, are subject to some uncertainty at the beginning of the motion, because acceleration records lose a certain amount of the initial ground motion in getting started. They “smooth out” rather than correct the effects of unstable accelerometer pendulums. The torsion pendulum, nevertheless, is well suited to play an important part in the practical solution of seismological as well as engineering problems.

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