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Fatigue strength analysis of a freight car bogie’s side frame
Lagerev I.A.
Nauchno-tekhnicheskiy vestnik Bryanskogo gosudarstvennogo universiteta , 2017, DOI: 10.22281/2413-9920-2017-03-04-374-380
Abstract: An approaches to the study of the fatigue strength of a freight car 18-100 bogie’s side frame are under consideration in this article. There is a decline of the quality of the manufacture side frames and increase of the number of defects, which leads to an increase the number of accidents. The relationship of the stress intensity factor and crack length for different types of fatigue cracks (surface crack and full perforation) was introduced. The algorithm of a bogie with a crack fatigue calculation was introduced. The inhibition of crack growth under overloading was taking into account during calculation. The additional numerical calculation of fatigue strength was performed by the specialized software package. Some defects of bogie larger than 1 mm is unacceptable as it dramatically reduces the fatigue strength.
Pre-design optimization of the manipulation system with hydraulic drive for mobile transport-technological machine
Lagerev I.A.
Nauchno-tekhnicheskiy vestnik Bryanskogo gosudarstvennogo universiteta , 2017, DOI: 10.22281/2413-9920-2017-03-01-26-45
Abstract: In the article has developed an optimization mathematical model and methodology of selection of optimal parameters of manipulation of systems of transport and technological machines, which allows to increase their service performance and competitiveness. Also developed the original structure of a comprehensive objective function taking into account the additive effect of any number of important indicators of quality in the formation of the optimal variant of the designed construction. Established the feasibility of using optimization approaches to definition of the basic dimensions of the kinematic scheme and parameters of the drive for the hydraulic manipulation system at the preliminary stage – the stage of development of the technical proposal for the design of the mobile machine. The approach enables the source to lay the subject to further design of the optimal values of the most important quantitative characteristics that determine the realization of the highest values of quality designed manipulation systems. For manipulation systems of hydraulic mobile machine appropriate to use such indicators of quality as its own weight and the capacity of the pumping installation. Pre-design optimization allows to comprehensively determine the optimum combination of a sufficiently large number of basic design parameters – the characteristic dimensions of metal constructions of manipulation systems (lengths, dimensions, cross sections, links, and mounting dimensions for hydraulic drives) and characteristics of the hydraulic equipment (working pressure and flow rate of the working fluid).
Optimal design of the cable metro with unified intermediate supports
Lagerev A.V., Lagerev I.A.
Nauchno-tekhnicheskiy vestnik Bryanskogo gosudarstvennogo universiteta , 2017, DOI: 10.22281/2413-9920-2017-03-04-400-414
Abstract: In article was formulated and solved the problem of conditional nonlinear technical and economic optimization of the distance between intermediate supports, uniform in height, during the design of the cable metro lines in highly urbanized city environment. The optimization problem involves a single-criterion objective function that expresses the cost of construction of the cable metro line (total cost of intermediate supports and their foundations, traction and carrying steel cables and technical equipment). The specified objective function subject to minimization by finding the optimal combination of the distance between intermediate supports and tension carrying ropes with accounting constructive, modal, structural and planning constraints in the form of nonlinear inequalities. Analysis was done of the influence of the step unification and minimum size of intermediate supports on their optimum step, the cost of intermediate supports, the cost of 1 km cable metro line for different values of the angle of the longitudinal slope of the surface relief along the cable metro line. With the increase of the step unify the discreteness increases: the width of the range of angles of the longitudinal slope of the surface relief within which the height of the supports remains constant, increases. The graph of step installation of unified supports along the cable metro line from the angle of the longitudinal slope of the surface relief also has discrete-step type. The transition to a larger height unified intermediate supports determines the need for installation of supports with a large pitch. Its value then begins to decrease monotonically with further increase of the angle of the longitudinal slope of the surface relief until it needs to transition to the new size of supports. Synchronous change in the optimal values of the height and step of the installation of intermediate supports, depending on the angle of the longitudinal slope of the surface relief leads to the fact that the optimal cost characteristics of the cable metro lines are smooth functions. It has an extreme character with a minimum at angles of inclination of the surface elevation ~5 degrees, which is associated with the form of sagging of the load-bearing ropes. Even for a sufficiently large step of the unification the largest difference in optimal value is almost insignificant: it lies in the range of 2...3%, increasing with increasing the angle of the longitudinal slope of the surface relief and unit cost of the intermediate support. Unification of intermediate supports according to the height and their step practically does not affect the optimal value for horizontal tension on the load-bearing ropes. It determined mainly by the angle of the longitudinal slope of the surface relief.
The effect of topography on the choice of optimal step intermediate supports along the line of the cable metro
Lagerev A.V., Lagerev I.A.
Nauchno-tekhnicheskiy vestnik Bryanskogo gosudarstvennogo universiteta , 2017, DOI: 10.22281/2413-9920-2017-03-03-253-272
Abstract: In article was formulated and solved the problem of conditional nonlinear optimization of the distance between intermediate supports during the design of the cable metro lines in highly urbanized environment, taking into account not the horizontal surface of the terrain. The optimization problem involves a single-criterion objective function that expresses the cost of construction of the cable metro line (total cost of intermediate supports and their foundations, traction and carrying steel cables and technical equipment). The specified objective function subject to minimization by finding the optimal combination of the distance between intermediate supports and tension carrying ropes with accounting constructive, modal, structural and planning constraints in the form of nonlinear inequalities. When constructing the objective function were considered three possible forms sagging of carrying ropes, which can be implemented for various values of the efforts of their tension. Analysis was done of the influence of the angle of the longitudinal slope of the surface relief along the line of the cable metro on the value of the optimal distance between intermediate supports depending on the design and cost of intermediate supports and at the cost of 1 km line of the cable metro. Quantitative calculations showed that with the increase of the longitudinal slope of the surface construction cost also increases with nonlinear increasing rate. The dependence of the cost of 1 km of line underground cable metro from the parameters of the relief is of extreme character with a pronounced minimum at small angles of inclination of the terrain surface about 3…60 degrees. The position of the minimum is quite stable and only slightly changes when enough significant change in the cost of intermediate supports and installed on them technological equipment. The most effective conditions for the construction of the cable metro is the terrain with considerable differences in altitude along the length of the route of transport: only if the surface inclination of more than 50…60 degrees cost of 1 km line starts to exceed the cost of 1 km line laid along a strictly horizontal surface.
Improving the safety of operation mobile transport and technological machines with manipulators when working with outriggers
Lagerev I.A., Lagerev A.V.
Nauchno-tekhnicheskiy vestnik Bryanskogo gosudarstvennogo universiteta , 2017, DOI: 10.22281/2413-9920-2017-03-03-296-302
Abstract: A new design of the outriggers for mobile transport and technological machines with manipulators was developed. A new type of a outrigger allow to increase the overall stability when manipulator is working. The main support complemented by an anchoring device for the counteracting for machine overturning and shear service loads. The working element of the anchor device is inserted into the base surface at an angle. This ensures the formation of stress fields between the main support and anchor device. The FEM-simulation confirm the effectiveness of new outrigger design. It is theoretically found that working on the anchor device trying to escape from the base surface. Its front surface is consistently crack the soil by the rotating displacement of its adjacent layers along lines that would lead to the formation of the characteristic buckling of originally flat surface. The main support is counteracting for this process. Thus a second shear direction (perpendicular to the first direction) is create and significant increase of additional holding moment for 10..40 % (depending on base chassis). If angle between anchor device and base surface is 30…45 degrees the maximum efficiency will be obtained.
Prospects of introduction of innovative technology overhead passenger traffic on the basis of the passenger ropeways for the modernization of the public transport system of the Bryansk city
Lagerev A.V., Lagerev I.A.
Nauchno-tekhnicheskiy vestnik Bryanskogo gosudarstvennogo universiteta , 2017, DOI: 10.22281/2413-9920-2017-03-02-163-177
Abstract: In relation to the current situation in the field of public transport in the Bryansk city was shown the main problems in the implementation of innovative technology for the aerial passenger transport on the basis of suspended passenger ropeways (Cable metro). Shows the advantages of the cable metro-based mechatronic technology transportation compared to the traditional suspended passenger ropeways. Was made the technical and economic feasibility analysis of the construction of the cable metro in conditions of a highly urbanized urban environment of large cities, metropolises and urban agglomerations. Presented the statistical data on the development of vehicles in the Bryansk city in the period 2004-2016 years and based on the analysis of these data shows the feasibility of the development of aerial passenger transport as the most high-speed and environmentally friendly mode of transport compared with automobile and electric transport. Considered the possible sources of financing of design and construction works and shows the commercial attractiveness of the project to potential investors in the framework of public-private partnerships. For existing urban development and major transport flows of the Bryansk city was formulated proposals for the location of future transport cable metro lines, order their gaskets, the formation routes of movement of the rolling stock. Made the estimation of labor and financial costs for the implementation of the project of modernization of the public transport system of the city of Bryansk on the basis of the suspended passenger ropeways.
Design and study of drive swivel joints for hydraulic manipulation systems of mobile transport-technological machines
Lagerev A.V., Lagerev I.A.
Nauchno-tekhnicheskiy vestnik Bryanskogo gosudarstvennogo universiteta , 2018, DOI: 10.22281/2413-9920-2018-04-01-14-30
Abstract: The paper presents the design and principle of operation of a new type of articulated connection of adjacent links of manipulation systems of mobile transport and technological machines – the drive swivel joints to provide a rotary relative movement of the links. Their design allows to combine the function of ensuring the continuity of the kinematic chain and the function of providing rotary movement adjacent units and without the use of additional external devices. The design of the device is protected by a patent of the Russian Federation. Drive swivel joints are an alternative to traditional designs of articulated joints with external power hydraulic drives. Developed a mathematical optimization model. The model is based on the minimization of the mass of the drive swivel joints when you complete the necessary design, installation, operating and strength constraints. Based on this mathematical model the proposed method of computer-aided design of the drive swivel joints, which is implemented in a computer program. A study was conducted of the influence of the main technical characteristics and magnitude of the operational load at the optimal weight and the optimal constructive dimensions of the drive swivel joints. It is shown that at equal freight-altitude characteristics of mobile crane-manipulator the drive swivel joint allows you to exclude a number of operational shortcomings of the traditional swivel: 1) development over time of the additional dynamic load of metal due to the increased clearances in connection; 2) lowering the volume of the working area of the crane due to the presence of external power of hydraulic drives; 3) the appearance of cracks due to fatigue failure of the elements of the attachment point of the hydraulic drives to the links of manipulation system. It is possible that the transfer of the hydraulic system for lower operating pressure, which increases the efficiency of the crane and the efficiency of the hydraulic drive as a whole, as well as reduction in operating maintenance costs.
The influence of anchoring of remote supports on the stability of mobile transport and technological machines equipped with boom lift manipulators
Lagerev A.V., Lagerev I.A.
Nauchno-tekhnicheskiy vestnik Bryanskogo gosudarstvennogo universiteta , 2018, DOI: 10.22281/2413-9920-2018-04-02-152-169
Abstract: The article presents a mathematical model for calculating the characteristics of stability against overturning for mobile transport and technological machines equipped with boom lift manipulators. This model allows us to perform a quantitative assessment of the degree of influence of anchoring of outriggers on the increase of cargo stability of mobile machines during loading and unloading operations. The mathematical model is universal: it allows to estimate efficiency of additional anchoring irrespective of a design of outriggers and placement of anchor devices. On the example of several types of mobile machines shows the effectiveness of outriggers with built-in anchor devices on the basis of piercing working elements. The quantitative analysis of the impact of anchoring on the increase in the weight of the transported cargo and the maximum departure of the handling system and the reducing the width of the support contour of the mobile machine was performed. The analysis of the influence of anchoring on the increase of the maximum allowed angle of inclination of the support surface on which the mobile machine can be operated under the condition of stability against overturning was performed. These positive effects of additional anchoring of outriggers are important in the operations of special mobile machines, in the operations of loading and unloading operations in extreme conditions or during rescue operations in the aftermath of natural and man-made accidents and catastrophes. The formulas for linear two-factor approximation of the main characteristics of cargo stability against overturning of mobile machines depending on the angle of inclination to the horizon of the support countour and the degree of anchoring of outriggers was proposed. The accuracy of the approximation is maximum within 10%. The proposed recommendations for the rational choice of approximation points can significantly improve its accuracy for specific operating conditions of mobile transport and technological machines.
Design of turning hydraulic engines for manipulators of mobile machines on the basis of multicriterial optimization
Lagerev I.A., Shatunova E.A.
Nauchno-tekhnicheskiy vestnik Bryanskogo gosudarstvennogo universiteta , 2016, DOI: 10.22281/2413-9920-2016-02-04-34-51
Abstract: In this paper the mathematical models of the main types of turning hydraulic engines, which at the present time widely used in the construction of handling systems of domestic and foreign mobile transport-technological machines wide functionality. They allow to take into consideration the most significant from the viewpoint of ensuring high technical-economic indicators of hydraulic efficiency criteria – minimum mass (weight), their volume and losses of power. On the basis of these mathematical models the problem of multicriterial constrained optimization of the constructive sizes of turning hydraulic engines are subject to complex constructive, strength and deformation limits. It allows you to develop the hydraulic engines in an optimized design which is required for the purpose of designing a comprehensive measure takes into account efficiency criteria. The multicriterial optimization problem is universal in nature, so when designing a turning hydraulic engines allows for one-, two — and three-criteria optimization without making any changes in the solution algorithm. This is a significant advantage for the development of universal software for the automation of design of mobile transport-technological machines.
Geochemical Exploration for Gold and the Association of As-Cu-Pb-Sn-Zn-Li in the Upper Proterozoic Granitoids of the Wadi Rumman Area, Southwest Jordan  [PDF]
I.A.A. Bany Yaseen
International Journal of Geosciences (IJG) , 2015, DOI: 10.4236/ijg.2015.610089
Abstract: The geochemical studies were conducted in an area covering about 15 km2of the south side of the Wadi Rumman area, SW Jordan. The study area included a part of a basement of complex exposed rocks in southwestern Jordan. The complexes comprised igneous and metamorphic suites, mostly from the late Proterozoic age. A systematic geochemical sampling was conducted using rock and heavy mineral-panned concentrate of geochemical samples. Fifty rock samples were collected from the granitic rocks, simple pegmatite dyke, quartz veins and alteration zone, which covered the area. Next, 45 heavy mineral-panned concentrate samples were collected from the alluvium in the stream sediment within the catchment area, and the dray was sieved to less than 1 mm grain size. The geochemical samples were analyzed for their trace elements and gold by using Ione Conductive Coupled Plasma Emission Spectroscopy (ICP-AES) and the Atomic Absorption Spectrometer (AAS) at Natural Resources Authority (NRA) Labs. The results of the geochemical analysis indicated the presence of gold and heavy minerals in the study area, a result considered abnormal in the rock samples. A strong positive correlation was recorded of Au with As, Cu and W (r =0.82, 0.7 and 1.0), as with Mo (r = 0.83), Cu with Pb (r = 0.83), Sn with Mo (r = 0.73), Mo with W (r = 0.97), Zn with W (r = 0.71), and Li with Bi (r = 0.7). These correlations revealed gold associated within the hydrothermal alteration, quartz veins and pegmatite dyke. Abnormal metals such as As and Bi were good path-finders to find Au. The HM samples showed low positive linear correlations among the concentrations of Au with As, Zn and Li, and negative linear correlations of Au with Pb, Sn, Bi and W. The combination of both rock and heavy mineral concentrate samples shows four geochemical anomalous areas of gold and heavy minerals. The geochemical signatures of Au and As in the Wadi Rumman appear to be in the hydrothermal alteration, quartz veins and pegmatite dyke, respectively. Heavy mineral concentration sampling delineated the Au geochemical anomaly in area 1 specificities with the rock geochemical anomaly of area 1.
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