Search

Copyright of Technical Diagnostics & Nondestructive Testing / Tekhnicheskaya Diagnostika I Nerazrushayushchiy Kontrol is the property of International Association Welding (Paton Publishing House) 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.)

Copyright of Radio Electronics, Computer Science, Control is the property of Zaporizhzhia National Technical University 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.)

Copyright of National Academy of Sciences of Armenia Reports / Doklady Nacionalnaâ Akademiâ Nauk Armenii is the property of National Academy of Sciences of the Republic of Armenia 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.)

Copyright of Proceedings of the National Academy of Sciences of Armenia. Mechanics is the property of National Academy of Sciences of the Republic of Armenia 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.)

Copyright of News of Kazakhstan Science / Novosti nauki Kazahstana is the property of NCSTE (JSC National Center for State Scientific and Technical Evaluations) 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.)

This paper presents the results of the development of automatic control systems for walking dragline excavator digging process. The process enables operational productivity to be enhanced through optimizing digging process. This also prevents extreme loads on machinery and hoist cable deflection. The paper also describes mathematical models of the electric drives of the main excavator machinery which form the bucket motion and the model of cable length change. Further the study will analyse the tructure of the control system and the automatic digging algorithm. Computer modeling findings are also described to confirm the operability of the automatic digging algorithm. Computer simulation of the processes in electric drives of main machinery of a walking dragline in digging operations was performed by means of SimInTech software. The automatic control system optimizes digging trajectory with very fast penetration with permissible overregulation following digging at a constant cut depth. The integrated system of dragline operation process control is practically independent due to the following factors: the automatic digging control system in combination with automatic systems for transporting the loaded bucket to dump and the empty bucket to the face; the automatic main machinery overload protection systems; and the system of control over safe bucket movement in the dragline working space.

In present paper the applied (one-dimensional) model of micropolar elastic thin beam with a circular axis is constructed including the variation principles, on the basis of the two-dimensional equations of micropolar theory of elasticity with constrained rotation written in the polar coordinate system and previously developed hypotheses for thin bodies. Within the framework of this mathematical model, boundary problems with applied values are formulated, which are solved in the final form. Further, the scheme of application of finite element method (FEM) is developed for the boundary problems of micropolar elastic beam with a circular axis with constrained rotation. The boundary problems stated above are solved by using the FEM and on the basis of an analysis obtained through the numerical results, the specific property of micropolarity of the material is established, that it raises the rigidity of the beam as compared with the classical theory. [ABSTRACT FROM AUTHOR]

Copyright of Radio Electronics, Computer Science, Control is the property of Zaporizhzhia National Technical University 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.)

Copyright of Radio Electronics, Computer Science, Control is the property of Zaporizhzhia National Technical University 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.)

Copyright of Automatic Welding / Avtomatitcheskaia Svarka is the property of International Association Welding (Paton Publishing House) 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.)

Paper is devoted to the development of the mathematical model and analysis of the problem of corium melt interaction with low-temperature melting blocks in the passive protection systems against severe accidents at the NPP, which is of high importance for substantiation of the nuclear power safety, for building and successful operating of passive protection systems. In the third-generation reactors passive protection systems against severe accidents at the NPP are mandatory, therefore this paper is of importance for the nuclear power safety. A few configurations for the cooling blocks' distribution have been considered and an analysis of the blocks' melting and corium's cooling in the pool under reactor vessel have been done, which can serve more effective for further improvement of the safety current systems and for the development of new ones. The ways for solution of the problems and the methods for their successful elaboration were discussed. The developed mathematical models and the analysis performed in the paper might be helpful for the design of passive protection systems of the corium melt retention inside the containment after corium melt eruption from the broken reactor vessel. [ABSTRACT FROM AUTHOR]

Th e cost optimal design of the majority of distribution and servicing systems consists of decisions on a number and on the locations of facilities from which customers' demands are satisfied however, there are severe difficulties in solving exact procedures because the underlying mathematical model is NP-hard. Th ese decisions should respect some additional conditions as a limited capacity of located facilities. Th e objective is to minimize the overall costs of the system and to satisfy all customers' demands. In this paper, we enrich the set of constraints by a new requirement called sub-pool compactness. Th is property of customer subset influences the quality of vehicle routes s ubsequently formed in a sub-set of customers served by the same facility. Th is paper formulates the problem of the enriched capacitated facility location considering compactness condition, formalizes and studies the property of compactness and suggests the compound method solving this problem. [ABSTRACT FROM AUTHOR]

Copyright of Proceedings of the National Academy of Sciences of Armenia. Mechanics is the property of National Academy of Sciences of the Republic of Armenia 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.)

The paper presents the mathematical model of the process contact membrane distillation. The proposed simplified mathematical model of KMD, which takes into account the change in the temperature of the solution and the distillate channel along the membrane and the membrane module height. As well as describing the change in temperature of steam flow in the pores of the membrane. An algorithm for calculating mathematical model of contact membrane distillation. [ABSTRACT FROM AUTHOR]

Purpose. Development of mathematical model of asynchronous traction machines in (d, q) frame of axis with taking into account the saturation of magnetic circuits. Methodology. In the paper, we used the method of dynamic inductances, which is connected with the use of a systematic study of properties of the traction motor. Findings. We have designed the analytical model of magnetic circuit asynchronous traction motor which takes into account action of the tangential and radial dynamic inductances. Based on this we have built tensor dynamic inductances rich machine, which was recorded in (d, q) frame of axis of equations of rotor and stator circles asynchronous traction motor taking into account the saturation. We suggest the method of dynamic inductances for construction of mathematical models of traction asynchronous engine. This allows to take into account the saturation of the main magnetic path for the modes with a wide range of changes in the flow of mutual induction between the stator and the rotor; saturation flow path scattering modes that are characterized by large current circuits of the machine; induction caused by processes of saturation between mutually perpendicular to the contours of the machine; as well as the joint saturation worker thread and threads scattering modes that are characterized by the significant size of the workflow and large values of currents contours of the machine. These modes are specific to asynchronous traction machines with consideration of the operation mode of traction electric rolling stock of Railways. Originality. We have considered variations in the magnetic state of traction induction motor, which is a topical issue in view of such a change in a wide range of operating modes of traction electric rolling stock of Railways. Practical value. The mathematical model allows taking into account the change of the magnetic state of asynchronous traction motor. It is required for creation of adequate drives control systems and systems for driving traction electric rolling stock of Railways. [ABSTRACT FROM AUTHOR]

Copyright of Radio Electronics, Computer Science, Control is the property of Zaporizhzhia National Technical University 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.)

This paper presents the results of analytical studies on determination of vibration characteristics of cylinder liners of diesel engines based on the development and application of mathematical models. Mathematical relationships for cyclic deformations in a longitudinal cylinder sleeve for circumferential and radial directions have been developed. Sufficient convergence of the model with the results of practical measurements given in the literature has been shown. [ABSTRACT FROM AUTHOR]

The paper is devoted to the development and study of the mathematical model for corium melt interaction with low-temperature melting blocks in the passive protection systems (PPS) against severe accidents at the NPP, and learning the peculiarities of construction and operation of the PPS. The configurations of cooling blocks' distributions considered and the results of their work in the corium cooling pool are compared to the data of other PPS's conceptions. The conclusion is made that the models developed and the results obtained may be useful for constructing the PPS against severe accidents. [ABSTRACT FROM AUTHOR]

Copyright of Military Technical Courier / Vojnotehnicki Glasnik is the property of Military Technical Courier / Vojnotehnicki Glasnik 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.)

Important nuclear power safety problem in touch with modeling of melted corium jet spreading inside the coolant pool is considered in the paper. It appears by development of the passive protection systems against severe accidents. The non-linear mathematical developed model is presented for the jet under reactor vessel pool for one of the perspective passive protection systems and the results of its analysis and studies are given. The performed analysis and the results of the numerical simulation done on the base of the model have allowed establishing the interesting behaviors of the system, which may be useful for the scientists, as well as the engineers-constructors of the passive protection systems against severe accidents. [ABSTRACT FROM AUTHOR]

Main goals of this paper are to define the concept of quality of sites for e-learning and importance of its evaluation, and to increase the ability of good, objective, and comprehensive evaluation through mathematical modeling of similarity measures. Similarity measure modeling is based on a new paradigm that stems from the theoretical concepts of Interpolative Boolean Algebra (IBA), which advances the concept of Case-Based Reasoning (CBR) and uses Interpolative Boolean Algebra (IBA) and Logical Aggregation (LA) as aggregation operators of similarity measures, in order to enable secondary (relative) quality evaluation of e-learning websites. Secondary evaluation is done on the basis of the degree of similarity with some of the "prototype" sites that are ranked (ordered) by experts in the primary (absolute) evaluation. The comparative analysis is shown for different types of realization of similarity measures modeling (Logical Aggregation, Euclidean norm, and Artificial Neural Networks). [ABSTRACT FROM AUTHOR]

The paper deals with a magnetic system on the basis of permanent magnets with a running circular channel. The permanent axially-symmetric transverse magnetic field operates on the aqueous medium. The physico-mathematical model is created for the motion of the charged particle under the action of the magnetic field of the system with allowance for the forces of interaction: magnetic field with a charged particle, charged particles between themselves and action of the stream on the particles. This paper determinates the criteria of parameters choice for the magnetic system. [ABSTRACT FROM AUTHOR]

Soil massif fracturing has a significant impact on change in engineering and geological conditions and, as a result, on stability of structures. Development of tectonic fracturing of local structures, taking into account the history of the process, its mechanism, resulting stresses in the massif and subsequent deformations of the rocks, led to a change in their structure, composition and strength characteristics, activation of hypergenesis and exogenous processes. The above circumstances require careful attention to identification of areas of increased fracturing, as the most dangerous in terms of risks during the construction of engineering structures. Field methods for assessing the fracturing of rock masses are laborious. It is not always possible to conduct instrumental surveys that allow solving the final problem – establishing patterns and sizes of damaged areas within local structures. The existing mathematical models for assessing fracturing, as a rule, are used to solve local problems: assessing the stability of developed pits, water content of rock masses, degree of fragmentation of individual blocks, etc. This information is not sufficient when assessing the areal distribution of weakened zones and clarifying their boundaries, since it does not take into account the history of the development of the structure, its parameters (dimensions, amplitude of the foundation block uplift, deformation properties of rocks). Aim. To develop a mathematical model of formation of the red-colored strata tectonic fracturing zones based on deformation criterion of destruction and mechanism of development of local structures. Results. The authors have developed a new mathematical model for predicting damage (fracturing) of terrigenous rocks of the red-colored strata that make up local structures, based on the mechanism of formation of local tectonic structures of the 3rd order and the deformation criterion of destruction. The paper introduces the mathematical dependencies that make it possible to predict the size (area) of taxa based on the data on the uplift amplitude of local structures. The results of the research can be used in assessing the fracturing of massifs composed of terrigenous rocks, and make it possible to judge the regularities in distribution of weakened zones within the entire massif being assessed.

The paper provides the research results representing the dynamics of species composition and production of wood stands in suramens of Mari El Republic Trans-Volga region as mathematical models. It was determined that there are 15 tree species growing on this territory, however the composition of a particular forest stand includes no more than seven tree species. Almost all suramen hydrotopes, with the exception of the swampy ones, are dominated by birch trees, the share of which is especially high in wet suramens, which proves the significant transformation of the forest structure. With the growth of tree stands the species composition inevitably changes towards original formations: in new and wet suramens the tree stand transforms into spruce forest mixed with linden and oak, while in wet suramens the forest stand transforms into spruce forest mixed with birch trees, and in swampy areas – into sticky alder forest. The greatest maximum plant biomass in new suramens is by pine trees, which are followed by spruce and oak trees. Aspen and birch trees are outsiders in this respect. In wet suramens the greatest plant biomass is produced by spruce trees while the least, by sticky alder trees. In terms of annual plant biomass increment the highest is by aspen trees in all types of suramens excluding the swampy ones. In complex plantations in terms of species composition with the growth of forest stand, there are distinct variations of the total tree bole biomass. This occurs due to gradual elimination of some species and their replacement with others. Forest stands in surames of Mari El Republic Trans-Volga region do not use their production capacity to the fullest. There are still reserves to be used. In new and wet suramens the birch and aspen may be replaced by conifers and in some cases even by oak. However, the final decision as on replacement should be taken based on economic calculations and ecological limitations. The paper also stresses that special attention of foresters should be paid on establishing the wood stands when the trees are still young.

Copyright of Proceedings of the National Academy of Sciences of Armenia. Mechanics is the property of National Academy of Sciences of the Republic of Armenia 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.)

This article is devoted to investigation of the environmental problems associated with the use of fuels for air-jet engines. The main components of the exhaust emissions of gases that result from the use of traditional and alternative aviation fuels are considered and analyzed. Particular attention is paid to assessment of the negative impact of the use of petroleum fuels for air-jet engines on the current state of the environment. The possibility of reducing emissions of certain exhaust gases from aircrafts using aviation biofuels is shown at the example of fuels obtained from vegetable oil-containing feedstock. The paper indicated the potential positive effect of the use of biofuels for aviation. [ABSTRACT FROM AUTHOR]

The main stages of information security incidents management are responding and investigation. These functions are assigned to specialized teams and centers (such as CERT -- Computer Emergency Response Team). The information security level of organization and whole state depends on CERT's performance. The analysis showed that CERT's performance assessment is not carried out properly. That's why in this paper basic performance parameters for cyberincidents response teams--it gives a possibility to assess CERT's performance during necessary period. The report on these parameters should be performed regularly such as once a week (month, year etc.) to obtain a complete picture of their changes and identify key trends. Using the obtained parameters will enable: to make quick management decisions, evaluate the level of CERT's specialists, to improve the CERT efficiency, to reduce losses associated with incidents, to improve user productivity, to use staff effectively and others. As well by influencing on the CERT's specialists actions and their correction can improve information security level of organization and whole state. Further on the basis of these parameters it is planned to develop mathematical models to ensure continuous improvement of the cyberincidents management. [ABSTRACT FROM AUTHOR]

The article presents several abstracts related to convergence topics which include convergence of solutions of integro-differential equations of heat and cold, use of computer algebra system in elementary number theory, and mathematical modelling of pollutants migration in soils.

The paper substantiates the conditions of seismic stability in the rock mass with cavities, on which protected objects are located, under constant seismic effects of mass explosions in quarries. Based on the ray-tracing method, a mathematical model of the interaction between longitudinal and transverse waves with a spherical cavity has been developed. An algorithm has been elaborated for determining the total static and dynamic loads along the spherical cavity perimeter from seismic explosion waves falling on the interface. The regularities of joint action of static loads have been determined, when located above the objects cavity, with allowance for the effect of the mass of cavity ceiling, the mass of the protected object above it and dynamic loads in the rock mass, and under the plane wave front fall on the cavity from different directions. The dependences of the change of total stresses referred to the incident wave stress at the interface of the rock mass and the cavity depending on the coordinate on its surface have been set. It has been established that the most dangerous points of cavity surface, in which destruction is likely to occur, are the cases when the seismic wave front falls on the cavity from the bottom directions typical for blasting operations in deep quarries. Under the arbitrary angles of the wave incidence on the cavity the stresses rearrange along the perimeter, which under different circumstances might lead to the mass breach and the fall of the protected objects, located above it, under the ground. [ABSTRACT FROM AUTHOR]

This paper focuses on development of mathematical model for shielded distributed lowpass filter based on eight-terminal circuit theory. The proposed model is assessed using different initial data. Recommendations for the simulation of filtration are given. [ABSTRACT FROM AUTHOR]

Relevance. To ensure the safety of hydraulic and hydropower facilities, to organize constant monitoring of their condition, including the installation of additional control and measuring equipment is required. It is also necessary to introduce modern information and diagnostic systems that allow in real time to assess the state of both individual elements of the structure, as well as mutually influencing structures and complexes of structures. At the same time, the results presented in the article are aimed for describing the fundamental structure a new generation of information and diagnostic system building, developed within the framework of a software and hardware complex. The aims of the work. The main purpose of the proposed system is to increase the level of monitoring to ensure the safety of hydraulic structures, which have a possible impact on each other during operation and construction. The tasks of creating a unified platform for assessing the safe state of hydraulic structures during the construction and operation of hydraulic structures (hydroelectric and pumped-storage power plants) are being solved, the foundations of a unified information-diagnostic system on a modular basis are laid, which allows comparing monitoring and measuring equipment readings, statistical samples and calculated values obtained within the mathematical modeling objects. Methods. The paper presents the structure of the interaction of individual blocks included in the information-diagnostic system, the interaction of the information-diagnostic system with the user for decision-making during the operation of the hydraulic structures. Results. A modular shell has been implemented, consisting of a combined information-diagnostic system, expert and calculation modules, which allows a comprehensive approach to the issue of safety of mutually affecting hydraulic structures. Software links have been developed to assess the change in parameters that can lead to deviations/irregularities in the operation of the hydraulic structures.

The article presents the list of singular indicators of technological support of technologies and the method of determining their actual values and their quality levels. According to the results of determining the quality level of technological processes, one of three management decisions can be made. The paper describes singular quality indicators that are directly related to the quality of technological processes in the machine-building industry, at the stage of design and preparation of technical documentation. And also presented are complex quality indicators, based on which determine the generalized indicator of quality of the evaluated technological process. As a result of the work the features of conformity assessment of technological processes and related mandatory requirements are formed. Also described is the process of obtaining a qualitative and quantitative assessment of the quality of the technological process with a detailed description of all necessary formulas.

Copyright of Res Humanitariae is the property of Res Humanitariae 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.)

In this paper, we investigate the nonideal dynamical system pendulum-electric motor. We construct and analyze the stability regions of equilibrium points. The study proposes a method of using such regions for searching the areas of deterministic chaos in the space of system parameters. Additionally, we demonstrate the falseness of applying the ideal mathematical models for studying the equilibrium points. Only the use of nonideal mathematical models, notably those models in which the oscillation source power is comparable to the power consumed by the oscillating system, allows us to make the right conclusion on the stability of equilibrium points. [ABSTRACT FROM AUTHOR]

In this paper, we obtain the nonviscous model of compact vortex close to the classical point vortex. The obtained vortex differs from the classical point vortex flow; its azimuthal velocity field is not potential. In addition to the classical flow solution, there is a term that makes the vortex compensated. The overall vorticity in it equals zero. Unlike the classical point vortex, the obtained one is compact and its velocity field meets the non-slip condition at the outer boundary like the (Taylor-Couette) flow between two coaxial cylinders. Furthermore, we introduce the nondimensional parameter, the function of radial coordinate indicating locally how the quasi-point vortex differs from the point vortex. The proposed model is an alternative to the point vortex one. The quasi-point vortex can be used in all relevant problems, where its counterpart (the point vortex) was used before. Crucially, its flow domain will always have finite scales just like it's in the nature. [ABSTRACT FROM AUTHOR]

In this paper, we consider the algorithm for calculating the object dynamic characteristics in the automatic control system. Specifically, the algorithm allows obtaining numerically pulse and transitive characteristics of the process relying on the reaction of a control system on the task change. The algorithm of this problem solving can be numerically applied by employing the Duhamel integral. Moreover, we consider the sample of this algorithm program implementation when modeling transients in the control system. [ABSTRACT FROM AUTHOR]

The paper develops the mathematical model of pervaporation of the organic component through a non-porous polymer membrane in the round crossing. We also present a system of equations describing the process of pervaporation separation of binary solutions. [ABSTRACT FROM AUTHOR]

The paper under scrutiny demonstrates numerical simulation results of thermal modes of the nanosatellite developed at the National Technical University of Ukraine "Kyiv Polytechnic Institute". It is designed to conduct scientific and applied research into the Earth remote sensing in the low Earth orbit with a solar pointing. In addition, we compare the obtained results with numerical simulation results of the "FalconSat-2" small satellite developed by the United States Air Force Academy. [ABSTRACT FROM AUTHOR]

The paper proposes the mathematical model for numerical solving of multi-parameter non-linear computational problem for analysis of the electrode melting process in the "electrode-arc" system. This model can be utilized under the conditions of pulsed metal arc welding by using argon or argon-based mixtures as a shielding gas. In addition, impulse parameters are calculated for the pulsed MIG welding. As a result, we obtain an area of impulse parameters which ensures the equality of electrode feed speed to its melting speed. [ABSTRACT FROM AUTHOR]

The paper considers an extruder as an object of mathematical modeling. We address the issue of mathematical modeling of the thermal mode control of extrusion process of polymeric materials. Crucially, we develop a mathematical model, which takes into account basic factors, influencing the increase of work efficiency of the extruder. [ABSTRACT FROM AUTHOR]

The present paper aims to construct the mathematical model of transportation and distribution of a certain item among consumers. This model takes into account stocking in tanks for temporary storage. To that end, we propose the algorithms based on the effective methods of nonlinear programming. Due to the general problem statement, these algorithms can be used for calculation of various types of distribution networks. [ABSTRACT FROM AUTHOR]

This paper deals with the system of automatic car control to ensure safety traffic. The cruise control system is designed utilizing the standard coefficients and incorporating the mathematical models of modal control. The automatic control system is simulated in SIMULINK. Moreover, we study the step response of this system taking into account white noise and inertia of the measuring instruments. [ABSTRACT FROM AUTHOR]

In this paper the research results of English CRN railway noise propagation prediction model applicability possibilities in the conditions of Latvian railway are described. Experimental measurements of railway noise levels from different types of trains were done in the area or railway station Dole and were compared with the CRN model numerical calculation results. Relatively small difference between the experimentally and numerically gotten results proves the reasonability of investigation of the currently developed mathematical CRN model for railway noise propagation applicability possibilities in the conditions of Latvian railway. [ABSTRACT FROM AUTHOR]

In this paper the English national mathematical model for railway rolling stock noise propagation prediction is described. CRN mathematical model distinguishes with the ease of numerical calculation implementation. The basis for numerical calculation is the information about noise level, which is being produced by one wagon. Knowledge of the noise level, which is being produced by one wagon, gives the possibility to calculate the noise level, which is being produced by a rolling stock, consisting of N identical wagons. Various important parameters are taken into account during calculation, such as: wagon type, number of wagons in the rolling stock and the rolling stock movement speed, as well many correction coefficients. The final calculation result is the A weighted equivalent noise level value for the certain track segment and for the day's or night's period of time. As the model's imperfection it is needed to note the following: noise frequency characteristics, variety of wagon types in the rolling stock and weather conditions are not taken into account. Applicability of the given model is limited to the conditions of normal movement of trains on a railroad tracks, i.e. presence of such phenomena as a roughness of a railroad track, squeal of wheel pairs, flanging can raise the SEL level for up to 20 dBA. [ABSTRACT FROM AUTHOR]

In this paper, we construct the universal correlations of mechanics of continuous environments on the base of moment chart of finite elements. They allow designing the thermostress state and the processes of processing and formation of such nonlinear working environments as polymers fusions, friable and plastic masses in the products, given that hardening and the influence of remaining tensions on the properties of the end products are considered. [ABSTRACT FROM AUTHOR]

In this paper, we define the arrangement of rectangles with fuzzy sizes in a breadth -- tangency, intersection, non-intersection. We also define the arrangement of rectangles with fuzzy sizes in the fuzzy size breadth -- tangency, intersection, non-intersection. Finally, we construct a new mathematical model of the one problem of the rectangle packing as a problem of the Euclidian combinatorial optimization on a set of fuzzy permutations. [ABSTRACT FROM AUTHOR]

The present paper develops a mathematical model of the continuous vibratory errors of the compensating accelerometer with a sensitive element resilient suspension. The described errors appear in most general conditions of a spatial oscillatory motion of the pendulous base. Furthermore, the analytic formulas for calculating these errors are obtained, and the calculations of these errors for the navigation accelerometer AK-6 are carried out. [ABSTRACT FROM AUTHOR]

This study describes a probabilistic approach to the mathematical formalization of ideas competition in the parliamentary process as an interaction between communication and regulation. The mathematical model presented in the paper elucidates the instability of "coalition-opposition" situation and demonstrates the necessity for the imperative mandate as a reaction to opposition "irreconcilability". [ABSTRACT FROM AUTHOR]

The technological development (knowledge plus skill) of contemporary society influences its thinking already not only by means of goods and services, but also directly by shaping the public opinion and immediately by formulation of the public structure and behavior. Scale spreading of technology or purpose-oriented use of existing certain tendencies and traditions of the behavior of people suggest the idea about a possibility of the formalizations (at least on qualitative level) of the public relations and relationships. Some aspects of the analysis of the limiting contact are considered in paper on the basis of the corresponding mathematical model. [ABSTRACT FROM AUTHOR]