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The possibility of using of para-aramid fibrids and pulp as a binder of para-aramid fibers during production of electrical insulation heatresistant paper have been studied. It has confirmed by microscopy the presence branched structures in para-aramid pulp and fibrids, as well as presence of the film structure in fibrids. The Influence of consumption of fibrids and pulp on general indicators such as density, tensile strength, elongation, tear resistance, electric strength, capillary rise, air permeability of non calendered and calendered heat resistant insulating paper have been obtained. It have been determined that after calendering the density of para-aramid paper increases about by three times. Based on the obtained results the optimal consumption of a binder has been found. It has been showed that using para-aramid fibrids or pulp as a binder is possible during production of para-aramid electrical insulation paper. The using of fibrids (at the same consumption) more increases the main indicators of quality of para-aramid paper than pulp. [ABSTRACT FROM AUTHOR]

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In this paper, a study of non-homogeneous time series, as a special case of a class of non-stationary time series, which are not given to stationary by integrating the 1st and 2nd order was carried out. Because of the presence of non-homogeneous components, time series is characterized by a non-linear trend, periodic components with variable amplitude, as well as a non-permanent structure. A method for identifying the series of this class based on statistical characteristics, using statistical tests and criteria was proposed. This method allows reasonable approach to selecting a method for forecasting a number of changes with respect to all the hidden features of the original data, as well as the reasons and assumptions of various forecasting methods. For example, in the construction of forecasting models of the non-homogeneous time series using statistical forecasting methods, such as AR (p), MA (q), ARMA (p, q), AR (p) + linear trend, ARCH (p), GARCH (p, q), SV (p), is inadequate in view of violating the requirements for applying these methods, in particular time invariance. An adaptive approach for forecasting non-homogeneous time series based on the method of singular spectrum analysis and presentation of time series in several phase spaces is proposed in the paper Another problem in forecasting the time series is a risk assessment in decision-making based on the forecasting model. A method for estimating the maximum level of losses in forecasting non-homogeneous time series with a given probability was developed in the paper. A confidence interval of forecasting non-homogeneous time series of exchange rates, which allows estimating the adoption of one or other solutions depending on the amount of the transaction was built. The results obtained in this paper can be used for a sound approach to the selection of a forecasting method in automated systems, as well as in the evaluation of making management decisions. [ABSTRACT FROM AUTHOR]

Improving the efficiency of the strategic development plans of the construction industry is possible by studying and elaborating the clustering algorithm of Ukrainian regions in the construction sphere. The aggregation algorithm of the feature space of the building complex of the territory was considered in the paper. The building complex of each area is described by a set of characteristics that can be called features. Herewith, the system of considered estimated figures cannot be fully used for the regional differentiation within the Ukraine since a number of indicators that form the system conditions are of national nature and do not contain a specific set of numerical and categorical data. Achieving the goal of improving the efficiency of the strategic development of the construction industry is possible provided solving the following problem: to construct an aggregation algorithm of features, allowing to determine the essential factors of influence and reduce the space dimension in clustering objects. The algorithm, considered in the paper is based on using two criteria: the correlation coefficient and the consistency criterion. This allows to reduce the dimension of the feature space of the building complex of the territory. As a result of the study, aggregates of indicators, in which the consistency criterion is equal to zero, were obtained. A study of the proposed algorithm allows to conclude on the presence of consistent relationships between the indicators, forming the functioning of the building complex of the region. It is an intermediate step in constructing the conceptual grouping schema of areas, as well as allows to construct a more accurate clustering of areas for management decision-making in the construction sector. [ABSTRACT FROM AUTHOR]

The problems of restoring the domestic compressor, Poltava, which is used in Ukrainian trolleybuses YuMZ (Southern Machine-Building Plant, Dnepropetrovsk) are considered in the paper. New technical documentation of the process of restoring the basic compressor assemblies, which affect the reliability and quality of the unit are developed. These studies are currently required as more and more rolling stock, operated at Ukrainian enterprises, is purchased at domestic enterprises. The trolleybus model YuMZ T-1, T-2 is also equipped with the domestic compressor. Since the compressor is a modern Ukrainian development, there is a need in the accompanying technical documentation for maintenance and repair. New technical documentation for the new domestic compressor are created and analyzed in the paper, which allows to improve the repair quality, operational reliability and safety of the trolleybus. The studies and the results are first obtained and important for both the enterprises, servicing this machinery, and the administrative board of the depot, which prioritize service quality improvement when using resource-saving technologies. [ABSTRACT FROM AUTHOR]

The approaches to developing the feasibility study of projects in the field of energy and energy saving are presented in the paper. This is important because, until recently, the post-Soviet countries continue to use the «reduced costs» for the study of the prospects of investment projects. However, it is not always feasible to use the products of leading companies-manufacturers of energyefficient equipment and technologies. The paper shows that developing the feasibility study of investment projects should be carried out in two stages: stage 1 -- preliminary (technical) study and stage 2 -- detailed (full) study. With specific examples, it is demonstrated that the prospects of using various types of lighting devices should be assessed with an allowance for possible risks, and also taking into account the market value of lamps and their disposal costs, considering the life of lamps, electricity tariffs and operation time during the day. Similar approaches to determining the prospects of using wind turbines have shown that it is necessary to take into account all significant factors, including political risks, and make decision based on the NPV and IRR values. Preliminary (technical) study of the projects often helps to avoid labor costs for developing the detailed feasibility study. This approach allows to be critical of «energy saving myths» (assertion of unconditional feasibility of using energy-efficient equipment, which allegedly must replace traditional equipment). In any case, it is the economic characteristics, such as NPV, Payback Period and IRR that should determine the feasibility of energy saving projects. [ABSTRACT FROM AUTHOR]

Cluster analysis is relevant and widely used in information systems, medicine, psychology, chemistry, biology, public administration, philology, marketing, sociology and other disciplines. However, the wide use causes coherence and unambiguity problems of the mathematical apparatus for cluster analysis. In particular, taking into account that clustering data can have different physical meaning and that the objects similarity criteria are not universal and can be defined for different applied problems in different ways, building alternative (to the already known) similarity coefficients, which meet the emerging needs for grouping objects of new applied problems is relevant. Therefore, the purpose of the paper is to improve the efficiency of solving the cluster analysis problems by developing general methods and algorithms for clustering objects based on the "angular" and ''length" metrics and binary relations. General method for clustering objects based on fuzzy binary relations is developed in the paper. Semimetrics, characterizing the proximity degree of vectors of object features by the "angular" and "length" similarity are determined. Clustering algorithms, based on grouping objects by the introduced angular and length semimetrics are built. Software implementation of this method has shown its effectiveness in solving various applied problems and ease of use. [ABSTRACT FROM AUTHOR]

Studying the free surface behavior in various flight conditions of spacecraft (SC) is one of the most important tasks of innertank hydrodynamics and the dynamics of this surface allows determining the nature of fuel reorientation. Fluid motion in rectangular-shaped SC tank under constant horizontal disturbing force is considered in the paper. In case of translational acceleration of tank there are no studies on the motion nature of free surface of fluid. In the paper such tasks are proposed to solve by dividing the potential of fluid speed by the relative component of speed potential relative to tank and its walls. This provision is the basis for analytical researches. The paper also gives the adaption of the proposed model to existing conditions and results of numerical calculations. This paper gives an algorithm for calculating the profile of free surface of liquid for flat tanks depending on the values of relative loading under a uniformly accelerated motion of tank with acceleration at various points of time. It was found that for approximate estimation, the value of tank bottom baring can be determined by constructing the points of intersection of free surface profile with a profile of the tank bottom. [ABSTRACT FROM AUTHOR]

The paper deals with the problem of developing e-books - the basic elements of electronic educational resources. One of the main issues of creating such web-books is highlighted, namely, algorithmization of creating training exercise on the example of solving a system of linear algebraic equations using Cramer's rule in the Adobe Captivate environment. The main features of training exercise is automatic help for students, as well as ability (even with wrong answers) to complete it with the corresponding theoretical explanation. The main features of the Adobe Captivate environment - a powerful software program for creating electronic books, are described in the paper. Namely, one can record a sequence of actions on the screen, but it will not be a typical video track, but a set of interactive slides, in which users can repeat actions on the screen, choose something etc. Therefore, development of training exercise for solving the SLAE (system of linear algebraic equations) using Cramer's rule in the Adobe Captivate environment was a solvable algorithmized problem. [ABSTRACT FROM AUTHOR]

Copyright of Technology Audit & Production Reserves is the property of PC TECHNOLOGY CENTER and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)