Arrangement Of Tracks Research Articles

INFLUENCE OF TRACK GEOMETRY CONDITION MONITORING ON RAILWAY INFRASTRUCTURE MAINTENANCE PROCESSING

This study analyzed the usage of data of track geometry measurement for railway infrastructure maintenance processing support and estimated its influence on railway infrastructure maintenance decision-making. Especially, the approach assessment of the influence of track geometry monitoring on railway infrastructure processing. The well-timed maintenance of the arrangement of railway tracks in allowable conditions is sufficient for the smooth and steady running of rail vehicles. The mechanism of track gauge widening during exploitation is usually gradual and relatively long-lasting. When are not detected in a timely manner, the final track failures often arise under the effect of additional factors, such as surpassed train speed limit, poorly maintained and functioning running gear of a rail vehicle, misalignment of rails, and extreme dynamical effects. A questionnaire considering the influence of the application of track geometry monitoring was formulated. An expert review was completed in order to perform a comparative analysis of the features of track geometry monitoring with the greatest influence on railway infrastructure maintenance processing. The data collected from respondents were processed using a multi-criterion estimation method, especially an interactive fuzzy linear assignment method. Finally, basic conclusions and considerations are given.

An integrated mesh with an anisotropic surface for unidirectional liquid manipulation.

Here, we adopted a simple method to prepare an integrated mesh with an anisotropic surface (IMAS). The motion mode of the droplet can be switched by changing the tilt angle of the IMAS. This low-cost and convenient operation method has great application potential in biomimetic functional surface preparation, microfluidics, etc.

Creating of luminescent defects in crystalline media by a scanning laser beam

Line-by-line two-dimensional step small-scale scanning irradiation of a transparent cubic LiF crystal was carried out by intense linearly polarized femtosecond laser radiation in the multiple filamentation mode. As a result, isolated longitudinal extended tracks consisting of induced color centers were formed in the medium. It was found that no transverse periodicity associated with the scanning step is observed in the arrangement of tracks formed by laser filaments. This is because inhomogeneities that stimulate filamentation are not contained in the laser beam itself but are formed randomly when the medium interacts with the first laser pulses and are supported and amplified by subsequent pulses. The efficiency of color center formation in crystals at normal laser beam incidence on the cube face depends periodically on the azimuth angle θ between the electric vector and the cube edge on the face, with the period of π/2. It was found that azimuthal dependences for defect formation (maximum at θ = π/4) and for carrier photogeneration (maximum at θ = 0) are in the antiphase. Calculations showed that the processes of self-focusing and filamentation controlled by the components of the third-order nonlinear susceptibility tensor are most effective at the orientation where θ = π/4. The experiment showed that at such an orientation, the critical power and the length of self-focusing decrease, and therefore, the density of the number of filaments in the beam section increases and, as a result, the average concentration of the color centers created by laser filaments increases.

Анализ структуры поездопотоков и вагонопотоков, поступающих в адрес российских портов финского залива

Objective: To study the traffic flows arriving at and departing from the main port stations which service the ports of the Gulf of Finland, including: Luzhskaya, Avtovo and Noviy Port in the period of maximum operation – January and February of 2015 and 2016. To analyze the influence of the daily volume of train traffic and the routing level on the required arrangement of tracks and lay-out of port stations (PS). Me- thods: Statistical data analysis was applied. Results: The hypothesis for applicability of γ-distribution for arrival frequency modeling of train arrival at PS was checked. The applicability of γ-distribution for arrival frequency modeling of train departure from PS was proved. Practical importance: Applicability and ro- bustness of generalized γ-distribution frequency function in theoretical calculations and in the construction of PS simulation model was justified, making it possible to adequately determine its required arrangement of tracks.

Optimization of forest sampling strategies for woody plant species distribution modelling at the landscape scale

Abstract Forest management increasingly needs the support of species distribution models (SDMs). However, different challenges remain to be addressed before the practical use and generalization of these models in the design of management measures in forest ecosystems. Due to the limited resources that are typically available for forest management, including the forest inventory phase, it is necessary to optimize the sampling approaches. Opportunistic sampling may be one strategy to reduce sampling costs, but the accuracy and suitability of the assessments derived from this sampling remain yet poorly addressed, particularly in forest landscapes. On the other hand, different forestry applications require landscape-wide estimates but still with fine resolution (ideally meters) as to guide management interventions. We, here, assess in detail the performance of the classical regular (systematic) sampling strategy and three different opportunistic samplings approaches along roads and tracks in a forest-dominated Biosphere Reserve (≈15,000 ha) in central Spain. We use specifically gathered field data in different inventories with sampling intensities of about 1–2 plots/km2. We compare, for each sampling strategy, the resultant consensus species distribution models for 28 woody plant species (trees and shrubs) developed at a spatial resolution of 25 m. We found that SDMs were reliable (AUC > 0.75) for 20 species out of 28 using either an opportunistic or/and systematic sampling. In general, opportunistic sampling was more efficient than systematic sampling, resulting in SDMs with a comparable accuracy for a lower inventory cost or in more accurate SDMs for the same sampling effort. This was mainly because the four sampling strategies adequately captured the environmental variability of the study area, and because plots in the opportunistic sampling were located at a sufficient distance from tracks to avoid potential edge effects. The minimum sample size and the species ecology should, however, be evaluated with caution in each case. We conclude that opportunistic sampling along tracks may be a practical and cost-effective option for SDMs in forest landscapes, as long as the density and spatial arrangement of tracks are sufficient to cover the full range of environmental conditions. This prerequisite could be evaluated, before the inventory phase, using available statistical approaches and spatial layers, potentially allowing for a remarkable saving of sampling resources in forest management planning. Species distribution models calibrated at the landscape extent with fine resolution could hence become ever more powerful and cost-effective tools for forest management and planning in both planted and natural forests.

An approach from answer set programming to decision making in a railway interlocking system

Railway interlocking systems are apparatuses that prevent conflicting movements of trains through an arrangement of tracks. A railway interlocking system takes into consideration the position of the switches (of the turnouts) and only allows trains to be given clear signals if the routes to be used by the trains are disjoint. There are many different approaches to automate decision making in railway interlocking systems (i.e., to automate supervising that the proposed situation is safe). Meanwhile the classic approaches are offline: only certain routes are allowed and their compatibility is decided in advance, our approaches take the decision on real time, so performance is key. We had previously developed Maple implementations of models based on matrix, algebraic (Grobner bases), logic and logic–algebraic approaches. They are independent from the topology of the layout and can be applied to small or medium size layouts. In this paper another completely new model (also independent from the topology of the layout), that directly translates the decision problem into logic programming, is presented. This new approach directly translates the problem in answer set programming (ASP) style, by defining relations and derived relations, from which the problem is solved using logic techniques inherent to ASP. The main procedure analyses the safety of a proposed situation and an auxiliary procedure returns, if they exist, the sections where a collision could take place. This declarative approach turns out to be much faster and efficient than the previous ones by these authors, and therefore can be applied to much bigger layouts.

An Auditory Display in Playlist Generation

A current area of research within music information retrieval is the automatic formation of music playlists: automatically creating a meaningful arrangement of music tracks. It is an application area particularly suited for accessing music on mobile devices as music collections are becoming too large to manually navigate. The growth of music streaming services means that even more vast collections of music are accessible from a mobile device. Much energy has been spent constructing the best algorithms to create a playlist, but less has been spent on how that algorithm is presented and accessed, particularly on a mobile device.

Numerical Solution of the Boltzmann Based Lubrication Equation for the Air-Bearing Interface Between a Skewed Slider and a Disk With Discrete Data Tracks

Discrete track recording (DTR) is a method for increasing the recording density of a data storage disk by use of a pattern arrangement of discrete tracks. The DTR track structure consists of a pattern of very narrow concentric raised areas and recessed areas underneath a magnetic recording layer. In order to design the air-bearing slider platform that houses the magnetic transducer for DTR application at very low fly heights, the influence of the disk surface topography as a surface roughness effect must be taken into account. This paper is focused on the numerical solution of the roughness averaged lubrication equation reported recently in the work of White (2010, “A Gas Lubrication Equation for High Knudsen Number Flows and Striated Rough Surfaces,” ASME J. Tribol., 132, p. 021701) and is specialized for the influence of discrete disk data tracks on the recording head slider-disk air-bearing interface subject to a nonzero skew angle formed between the slider longitudinal axis and the direction of disk motion. The generalized lubrication equation for a smooth surface bearing and appropriate for high Knudsen number analysis is quite nonlinear. And including the averaging process required for treatment of a nonsmooth disk surface, as well as the rotational transformation required to allow for a nonzero skew angle, increases further the nonlinearity and general complexity of the lubrication equation. Emphasis is placed on development of a numerical algorithm that is fast, accurate, and robust for air-bearing analysis of complex slider surfaces. The numerical solution procedure developed utilizes a time integration of the lubrication equation for both steady-state and dynamic analyses. The factored-implicit scheme, a form of the more general alternating-direction-implicit numerical approach, was chosen to deal with the two-dimensional and highly nonlinear aspects of the problem. Factoring produces tightly banded coefficient matrices and results in an algorithm that is second-order accurate in time while requiring only the solution of tridiagonal systems of linear equations in advancing the computation from one time level to the next. Numerical solutions are presented that demonstrate the performance of the computational scheme and illustrate the influence of some discrete track parameters on skewed air-bearing performance as compared with a flat surface data storage disk.

A logic approach to decision taking in a railway interlocking system using Maple

Railway interlocking systems are apparatuses that prevent conflicting movements of trains through an arrangement of tracks. A railway interlocking system takes into consideration the position of the switches (of the turnouts) and does not allow trains to be given clear signals unless the routes to be used by the trains do not intersect. A new model, based on Boolean Logic, and independent from the topology of the station is presented in this paper. According to this new model, any given proposed situation is safe if and only if a certain set of formulae (translating the position of trains and the movements allowed – the latter depend on the position of the switches and the colour of the semaphores) is consistent. The main procedure analyses the safety of a proposed situation and returns, if they exist, the sections where a collision could take place. The fact that trains could occupy more than one section is considered. The code of the corresponding Maple implementation is surprisingly brief.

Actuation mechanism of plasticized PVC by electric field

The deformation of plasticized poly(vinyl chloride) (PVC) gels in an electric field was considered to result from the electric charging and the interaction between the electrodes. Basic experiments were carried out to investigate the deformation response of PVC gels. PVC and the plasticizer dibutyl adipate (DBA) showed strong polarization phenomena in an external electric field. This was confirmed by a constituent electric response test, in which PVC particles flocked together at the anode and adopted an arrangement of line-like tracks in the electric field due to the contribution of DBA as a solvent, while DBA moved from cathode to anode very quickly. The space charge distribution of PVC gel was clearly different from that of poly(methyl methacrylate) (PMMA) film and silicone film. The intrinsic polarization charges of PVC gel accumulated on the gel surface near the anode, and their intensity was much stronger than for PMMA and silicone. With this comparison the polarization of PVC gel was further confirmed. Furthermore, by using a force measurement method, the Maxwell force and the variation of interfacial adhesive force were evaluated. The force generated in the PVC gels was expected as the result of polarization response of charges, and it mainly took place between the gel and the anode due to the accumulated negative charges on the surface of the PVC gel near the anode. With this force, the PVC gel was deformed asymmetrically, resulting in creeping motion along the anode. Thus the deformation of PVC gels depended on the attractive force between the two electrodes due to the polarization of accumulated charge density in the electric field.

The Water Degradation Yield and Spatial Distribution of Primary Radicals in the Near-Discharge Volume of an Electrolytic Cathode

The features of combination and scavenging reactions of OH radicals were experimentally investigated in comparison with the decomposition of water by the action of anodic microdischarges on an electrolytic cathode. The assumption was proved that the formation of primary water degradation products occurs mainly in the liquid phase in tracks of fast particles entering the solution from the discharge plasma. The local concentration of OH radicals in tracks was estimated at the level of 10–2 mol/l; although the peripheral regions of tracks can overlap because of the close arrangement of tracks in the near-discharge layer of the solution, the central regions of increased OH concentration may be considered as isolated.