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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.
Risk assessment during operating self-propelled lifting jib cranes in conditions of insufficient information
Lagerev A.V., Konchits S.V., Bleyshmidt L.I.
Nauchno-tekhnicheskiy vestnik Bryanskogo gosudarstvennogo universiteta , 2017, DOI: 10.22281/2413-9920-2017-03-02-203-220
Abstract: Presents the results of statistical analyses identified by the expert diagnostics of defects of the self-propelled lifting jib cranes, spent a normative term of exploitation. The greatest number of defects associated with the destruction and deterioration of structural elements, the occurrence of fatigue cracks and a violation of the conditions of operation of the equipment. The greatest number of defects occurs in the hydraulic system of cranes, the rope-block system, and rarely in steel structures. To conduct risk analysis of self-propelled jib cranes in case of insufficient information, proposed the method of expert estimations. It allows to assess the impact of potential defects on self-propelled jib cranes on the value of the economic damage of the crane and moving cargo and the value of the traumatic exposure on men. The proposed list of possible defects self-propelled lifting jib cranes and a checklist of questions about the degree of influence of these defects. Proposed calculated dependences to the approximate calculation of the magnitude of technical risk in the operation of self-propelled jib cranes. The results of statistical analysis of expert estimations for each possible defect and performed their ranking in terms of impact on the magnitude of the economic damage of the crane and moving loads, the value of the traumatic exposure. Was calculated the value of technical risk for the surveyed taps.
Elucidation on Reactions Thermodynamics and Kinetics of OFC-A of Steels  [PDF]
A.V. Adedayo
Journal of Minerals and Materials Characterization and Engineering (JMMCE) , 2010, DOI: 10.4236/jmmce.2010.97043
Abstract: The basic principles of Oxyfuel cutting of metals lie in rapid high-temperature oxidation of the cut metal. Considerable proportion of the published work on the subject of oxygen cutting, the details of the oxidation reaction are overlooked or confused. Most often, physical characteristics of oxidized material is attributed to that of iron rather than iron oxide. The analysis of the oxidation reactions pertinent to Oxyfuel cutting of steels has also been majorly ignored. The oxidation process of iron and steel though similar in some respects, yet, in other aspects, show significant differences. This paper presents experimental and theoretical elucidation on reactions thermodynamics and kinetics of oxyfuel cutting processes of steel. Six 10mm metallurgy steel rods of different wt% C were flame cut using different acetylene and oxygen pressures. The composition of the steel rods used ranged from 0.16 wt% C to 0.33wt% C. Acetylene pressures used ranged from 3.45 x 10-2 N.m-2 to 5.52 x 10-2N.m-2, while oxygen pressure ranged from 2.76 x 10-1N.m-2 to 3.17 x 10-1 N.m-2. The result shows that the cutting rates decreased with carbon content of the steel as a result of reduction of iron oxide during decarburization reactions. Theoretical models of the thermodynamics and kinetics of cutting process pertinent to steels are also discussed.
Development Processes of Globular Microstructure  [PDF]
A.V. Adedayo
Journal of Minerals and Materials Characterization and Engineering (JMMCE) , 2011, DOI: 10.4236/jmmce.2011.107050
Abstract: Semi solid metallurgy offers distinct advantages over other near-net-shape manufacturing processes. By this process, components are produced from slurry kept at a temperature between the solidus and the liquidus isotherms, resulting in breakdown of the dendritic structure. A new structure in which the morphology of the crystals of the primary phase is globular evolves. In this present paper, the importance of globular structure is identified. The theories of evolution of globular crystals in thixo–processing are identified and discussed.
Influence of Mould Heat Storage Capacity on Properties of Grey Iron  [PDF]
A.V. Adedayo, B. Aremo
Journal of Minerals and Materials Characterization and Engineering (JMMCE) , 2011, DOI: 10.4236/jmmce.2011.104028
Abstract: Grey cast iron is characterized by presence of a large portion of its carbon in the form of graphite flakes which are observable in their microstructures. Their properties are significantly dependent on the micro-constituents of the, cast iron components. A way of controlling the microstructure of cast iron is through the controlled cooling rates during solidification. To control cooling rate, the heat storage capacity of the mould is important. This paper presents the characteristic effects of graphite flake sizes on some mechanical properties of grey cast iron. Six mould materials with heat storage capacities ranging from 1.52 kJ.m-2.K-1.s-1/2 to 2.16 kJ.m-2.K-1.s-1/2 were prepared and used to cast some grey cast iron samples whose microstructures were observed by optical microscopy. Mechanical properties of the grey iron were evaluated. The results show that the properties increased with the heat storage capacity of the mould. Also, the microstructures show a dependence on heat storage capacity of the mould.
Anthropological perspectives on injections: a review
Reeler,A.V;
Bulletin of the World Health Organization , 2000, DOI: 10.1590/S0042-96862000000100020
Abstract: qualitative studies from developing countries have pointed to the widespread popularity of injections. in addition to their use by formal and informal providers and traditional healers, there is now increasing evidence of the use of injections and injection equipment by lay people. epidemiological research links the large number of unsafe injections to serious bloodborne infections such as viral hepatitis b and c and acquired immunodeficiency syndrome (aids). the present article examines the reasons behind the demand for injections by consumers and the administration of unnecessary or unsafe injections by different types of provider. interventions aimed at reducing the risk of unsafe injections are discussed in relation to cultural and social factors as well as those factors associated with health systems. suggestions are made for approaches to the design of such interventions.
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