Software & Systems

Articles of journal № 2 at 2014 year.

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31. Modeling dynamic problems of thin-walled framework [№2 за 2014 год]
Author: Chernov S.A.
Visitors: 9307
The article describes the flexural and torsional vibrations of an open profile thin -walled rod with one cross section symmetry axis. When solving the rod vibrations problem the static task is considered with the addition of inertia forces, i.e . using the principle of Dalembert. The weight and stiffness of the rod are accepted as constant. Based on energy relatios the mass matrices are obtained in the explicit form of thin-walled rod finite elements that are in bending and torsion, and also a spatial finite element. The article shows comparative calculations on free and forced vibrations of П-shaped frame that is formed of rolled channel and double tee. The frame model uses beam finite and thin -walled rod elements, i.e., the flexural form of vibrations without considering torsion-al inertia of the rods and the torsional vibrations form respectively. There are values of the lower frequencies and corresponding modes from frames plane in the beam-column joint with free vibrations, as well as the maximum normal stresses in the profilecross -sections. The method of modeling is implemented in applications computer programs.

32. Adjustment of the forging capd decision using the fuzzy set theory [№2 за 2014 год]
Authors: Kanyukov S.I., Konovalov A.V.
Visitors: 10410
The paper describes a new approach to creating the CAPD for press forging of shafts under uncertainty cond i-tions of the technological constraints boundaries imposed on the design parameters due to the i nsufficient formalization of the subject domain. As a result, the technological solutions related to the design process are various for different enterpri ses, and they are often ambiguous or even contradictory within one enterprise. The paper consideres two stages of the computer-aided design of the forging technology. At the first stage the design process is automated. All technological restrictions (in the base of the normative -reference information) are strictly impl e-mented. At the second stage the design is repeated. But this time the effects on the design parameter carried out by the user in active dialogue regime are taken into account. The paper pays special attention to the procedure of the design parameter co n-trol. The value of each parameter must belong to the specific technological interval with fuzzy boundaries. The novelty of the paper is the fact that the uncertainty of technological interval boundaries is formalized by the theory of fuzzy sets and fuzzy reasoning. The concept of membership function and quality criteria of designed process is input and filled with the physical meaning. Using the developed approach to creating forging CAPD allows increasing the work stability of the system in real pr o-duction conditions, giving a comparative evaluation of the quality of the received design decisions and facilitating signif i-cantly the implementation of the system in various enterprises.

33. Creating a multi-model system to make optimal management decisions in the company [№2 за 2014 год]
Authors: Belyaevа M.A., Burlyaeva O.K., Syrova I.V.
Visitors: 12274
The article shows results of the developed system of decision-making support in meat packing industry. The base is models that developed using imitating systems Anylogic, Simplex3, BPwin 7.1 and Aris 7 source environments; sys-tem of structural and parametrical modeling. The computer multimodel system solves the problems of of technical supply evaluation, economic status assessment of meat packing enterprises, revenue forecasting and planning, expenses and losses, calculation of the number of employees at and payroll, evaluation and the enterprise structure planning, identification of priority directions of development of meat packing industry, planning the funds for construction, repair and maintenance of i nfrastructure, allocation of the major risk factors and emergencies forecast, the calculation of the volume of sales for finished products. The system helps to specify a marketing situation, pricing policy and determine the trade off prices, suitable for producers and consumers, determine the demand for meat products according to its range. These problems can be solved using modern methodologies, software and systems, creating company models (both the static and dynamic), the data multivariate analysis, their "export" and "import" from one software product to another, integrating the repository and enterprise information system into one. Computer multimodel decision-making support system gives the possibility to improve the process of meat production and helps managers, entrepreneurs in the meat business.

34. EaaS model based approach to cloud services provision [№2 за 2014 год]
Authors: Zalozhnev A.Yu., Chistov D.V., Shuremov E.L.
Visitors: 8269
Prices and potential volumes optimization can be the basis for the cloud services provider’s marketing policy. This activity is aimed to developing and providing with a wide range of cloud services for clients. There are several cloud service models depending on the users’ needs. An EaaS model is considered as a service model. A public cloud is considered as a deployment model. This article discusses one of possible approaches to the provision of cloud computing services by services provider. The potential volume of provider's cloud service is not formally limited in each moment. Payments for cloud services are proportional to times of their use. Cloud services provider is considered as a single profit center. Under ex-penditure means variable expenses for cloud service each species creating and other operating expenses. The other operating expenses add if their allocation to per unit volume of cloud service each type is possible. The cloud computing services pr o-vision optimization problem is reduced to the problem of determining the profit maximizing prices and potential volumes of cloud services. These prices and potential volumes have to maximize the service provider’s operation profit. O ptimization criterion is a quadratic form. The appropriate conditions allow stating that the solution considered corresponds to the profit maximum. The results are valid if no limitations on providers’ cloud services potential volumes. If it is so, then the problem formulation is modified with these l imitations taking into account. This problem is a quadratic programming problem. The computer model based on spreadsheets was developed for calculations. Study results of the obtained model are discussed.

35. On some inverse spectral problems for an arbitrary perturbation of the bi-harmonic operator with singular coefficients [№2 за 2014 год]
Author: Serov V.S.
Visitors: 5644
The classical inverse boundary spectral problem for any perturbation of the bi -harmonic operator with singular coefficients from some Sobolev spaces is considered. The problem is formulated as follows: Do the Dirichlet eigenvalues and some derivatives of the corresponding normalized eigenfunctions at the boundary of smooth bounded domai n uniquely determine the coefficients of this operator? We proved the first step of this problem, i.e. we proved that the Dirichlet eigenvalues and the derivatives up to the second order of the normalized eigenfunctions at the boundary uniquely determine t he so-called Dirichlet-to-Neumann map that corresponds to the Friedrichs self-adjoint extension of any perturbation of the bi-harmonic operator with singular coefficients. The main role in this proof is played by the existence of the Green’s function and its estimates up to the boundary of the domain. These facts will allow us to prove the classical Borg-Levinson theorem for the operators of fourth order of such type.

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