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Shear pads are devices used to improve vehicle dynamics performance on heavy haul railways wagons. In this work, we present a method to determine the elastic properties of such components using experimental/numerical approach. The final goal is to provide adequate input to multi-body analysis software commonly applied to study and design railroad vehicles. We also considered the effect of side frame compliance to primary suspension performance, a influence that is often neglected on this type of study. Our results show that the application of shear pads can indeed promote a significant reduction of wheel and rail wear by decreasing the total frictional energy T γ. We also show that, under the simulated conditions, the most important stiffness coefficient to wear is the longitudinal one. [ABSTRACT FROM AUTHOR]

Turnouts are among the weakest links of railway lines, but the derailment risk of vehicles passing the through route of a turnout is seldom considered. The potential factors affecting derailment are screened according to field investigations of a train derailment case at the through route of a turnout. A detailed wagon-turnout interaction model considering the non-uniform cross-sections of turnout rails and the interaction between adjacent wagons is developed and validated. Through numerical simulation, the dynamic performance of an empty wagon passing the through route of turnout at a low speed is studied. When the wagon passes the turnout under the continuous lateral force condition, the wheels climb onto the rail head at the switch area in the facing direction, while the derailment occurs at the frog area in the trailing direction. Moreover, the possibility of derailment of the empty wagon increases with increasing coupler force and wheel-rail friction coefficient, and with decreasing speed. To improve the safety of empty wagons in the turnout area, rail lubrication should be implemented to reduce the wheel-rail friction coefficient, and large braking forces should be avoided. Furthermore, the wheel surface condition after re-profiling requires continuous attention. [ABSTRACT FROM AUTHOR]

The proper technical condition of a vehicle and rail track in operation is a key aspect in terms of safety and travel comfort. This issue is of particular importance for operators and managers of rolling stock and rail infrastructure. Currently, many diagnostic systems have been developed to monitor the technical condition of selected vehicle systems or rail track from the viewpoints of both the vehicle and track. This article proposes the use of vibration signals in selected quantitative and qualitative analyses as the main diagnostic parameter. For this purpose, over a dozen vibration measurements were carried out during the normal operation of a freight wagon as part of a so-called passive experiment. Measurement points were located on the axle boxes of the wheelsets. The proposed research methodology served as a basis for comparative analyses of the selected operational cases that were investigated. The most important conclusion from the study is that it is possible to monitor the technical condition of vehicles and tracks in real time on the basis of measurements of vibration accelerations at the vehicle level. This directly increases the service life of rolling stock and optimises operating costs by changing the maintenance strategy to one that takes into account the idea of modern on-board technical diagnostics. Another important aspect is the possibility of the varied use of the proposed measurement system, depending on the purpose of the research, which is also associated with the diagnostician's experience in processing vibroacoustic signals and the utilisation of simple or complex quantitative and qualitative analyses. [ABSTRACT FROM AUTHOR]

Studying the wagon accumulation process and the laws of accumulation cost is of great significance for determining the suitable conditions of wagon accumulation and shortening the accumulation time. Here, the process of relaxed fixed time accumulation is first taken as a stochastic service system, and derives the theoretical formula for the accumulation cost. Then based on actual data of wagon flows, a simulation model is built to analyse the influence of parameters in the theoretical formula such as the coordination of the traffic diagram and the accumulation process, the sizes and intervals of the arriving wagon groups and the minimum number of wagons. Finally, through comparing with the accumulation cost of fixed train length accumulation mode and considering the benefit of changing the minimum number of wagons in train sets, the optimal minimum number of wagons in the relaxed fixed time accumulation mode under different wagon flow intensities is determined. [ABSTRACT FROM AUTHOR]

This paper uses vehicle system dynamics simulations to investigate curving resistance generated from the wheel-rail interface. More than 600 simulations were conducted using a freight wagon model to investigate the implications of curve radii, vehicle speeds and track superelevation for curving resistance, as well as the changes of curving resistance with wheelset Angle of Attack (AoA) and track cant deficiency. The results show that with the same curve radius, vehicle speeds and track superelevation can change the simulated curving resistance by 13–26%. Comparatively, vehicle speeds have stronger influences; resistance variations due to speed changes were about 16% larger than those due to superelevation changes. When the speed of the specific wagon was lower than 60 km/h, curving resistance decreases with both the increase of speed and the decrease of track superelevation. However, these trends can change to their opposite directions when speed reaches 70 or 80 km/h. Curving resistance increases with the increase of AoA and with the decrease of curve radii. The analyses of cant deficiency show that overbalanced speed cases generally have lower curving resistance. The results of the specific wagon indicated that zero cant deficiency did not generate the minimum curving resistance. [ABSTRACT FROM AUTHOR]

Simulation computations represent a very effective tool for investigating operational characteristics and behaviours of vehicles without having a real product. The rail vehicles sector is typical, in that simulation computations including multibody modelling of individual vehicles (i.e., wagons) as well as entire trainsets are widely used. In the case of designing rail vehicles, running safety and ride comfort are two of the most important assessment areas. The presented work is focused on the research of the dynamical effects of a rail vehicle while running on a railway track created in a commercial multibody model. There is a lot of research focused on the investigation of dynamic performances while a rail vehicle is running on a flexible railway track. The real operation of a rail vehicle meets problems on track, where the stiffness-damping parameters of a railway track vary in transient sections (e.g., the exit of a tunnel). This work brings a contribution to research related to the assessment of the dynamic response of a rail vehicle on a chosen track section. A passenger railway vehicle is chosen as a reference multibody model. Simulation computations were performed for three different railway track models, i.e., for a rigid track model and for a flexible track model defined in two different manners. The stiffness-damping parameters of the rail vehicle are defined symmetrically in relation to the longitudinal axis of the vehicle, e.g., they are the same values for the left and right side. The centre of gravity is not located symmetrically, but it is partially shifted in the lateral direction. This can be observed in the results of wheel forces and their waveforms. There are evaluated values and waveforms of the vertical wheel forces, the lateral wheel forces and the derailment quotient. The obtained results have revealed the influence of the railway track formulation in the model on the output parameters. [ABSTRACT FROM AUTHOR]

There have been numerous attempts and investigations carried out with the objective to reduce the noise generated by railway freight wagons because noise is one of ever-present negative environmental pollution phenomena. This resulted in strong legislation requirements on noise reduction in railway transport, in the case of freight wagons, only exterior noise is a problem. However, the extremely hard metal structures of the wagons running on hard rails naturally generate high magnitudes of acoustic energy. One big initiative, especially in Germany, seeks a solution in replacement of the cast iron brake pads with the composite one which should result in so-called "silent trains". But braking is used only during a minor part of the train run, leaving most of the acoustic phenomena of the train run unaffected. In our research, we focused on freight bogies type Y25Ls(s)e-K that are used, including in Slovakia. We simulated the structural natural frequencies to predict vibrations and consequent sound generated by these vibrations. The idea was to localize the vibrations and propose possibilities of noise attenuation. The more realistic view about sound fields was obtained by practical measurements on a moving bogie. Measurements on the test track at a maintenance workshop were done by using a digital acoustic camera Soundcam. For attenuation of noise radiated by the bogie frame, acoustic silencers made from recycled porous fiber material have been applied to the bogie frame. To determine the acoustic difference, the material was applied only on half of the bogie, and then the measurements were carried out. The results showed a promising improvement in reduced noise radiation, which gives support for further research in this area with more precise simulations and more precise coating of the bogie frame as well as the proposal and measurement of noise-attenuating coatings of other structural parts of the freight wagons. [ABSTRACT FROM AUTHOR]

The problem of delivering and fetching wagons at a railway station with mixed-shaped goods operation sites is considered, with a view to minimizing the running time between goods operation sites and waiting time of the locomotive in the planning period as the optimization objective. A general mathematical model for delivering and fetching wagons at a railway station with mixed-shaped goods operation sites has been formulated. The methods of judging and processing reverse of delivering and fetching wagons, dividing batches, and judging number of wagons for batch operation are provided to determine the feasibility of the solution, and an improved simulated annealing algorithm is introduced as our algorithm to the model. Finally, an experimental station is taken as an example to verify the model and algorithm. The results show that simulated annealing algorithm is relatively superior in computational efficiency and result compared with genetic algorithm and tabu search algorithm, the computing time of the algorithm provided can meet the requirements of planning shunting operations in railway station, and the model proposed is universal for other layout forms of GOSs and different operation forms. [ABSTRACT FROM AUTHOR]

Hot forging forming of railway wagon bogie adapter is a new railway wagon bogie adapter processing technology. In this paper, a hot forging die for railway wagon bogie adapter was designed, and the forming quality were analyzed by using DEFORM-3D software. Then, the feasibility of the process was verified by experiments. It was found that using this mold can eliminate the defects such as loose as-cast in metal smelting process, optimize the microstructure, forging products with good density, product quality and other characteristics of stability. [ABSTRACT FROM AUTHOR]

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This article examines the concepts of colonial and migrational anxiety by discussing North American accounts of experiences on wagon trains in the mid-nineteenth century. The focus is on the personal accounts of emigrants across the plains contained in travel diaries and private correspondence. This study aims to identify markers of anxiety identified in a hitherto unexplored primary corpus by discussing these signifiers in terms of discourses which were constructed to mask the realities of the migrational process. The study will draw on the theoretical basis of colonial anxiety in South Asia, discussed by scholars such as Homi Bhabha, Edward Saïd and Ranajit Guha in order to draw parallels between the two contexts. Through the examination of North American wagon train experiences in this way, it will be argued that their role was both colonial and migrational, and should thus be seen as a point of intersection for colonial and migrational anxiety. [ABSTRACT FROM AUTHOR]

Purpose. To study the feasibility of using the fi llers for the gondola car bearing structure components. This makes it possible to reduce both damage to the gondola car bearing structure components during operating modes of loading and the cost of unscheduled repairs. In addition, it can improve the effi ciency of railway transport operation. Methodology. In order to substantiate the use of aluminium foam as a fi ller for the gondola car bearing structure components with a closed box-section, a computational modeling of loading under the most unfavorable operating mode, such as shunting collision, has been performed. Gondola car 12-757 model built at PJSC Kryukovsky Railway Car Building Works is chosen as a prototype. The calculation is performed using the fi nite element method implemented in the SolidWorks Simulation (CosmosWorks) software package. The fatigue strength and natural vibration frequencies of the gondola car bearing structure with a fi ller of its components have been calculated. The natural vibration frequencies of the bearing structure of the gondola car are calculated. The design service life of the gondola car bearing structure has been determined. The main indicators of the gondola car bearing structure dynamics have been studied. The calculation is made in a plane coordinate system. In this case, the mathematical model is solved by the Runge-Kutta method. Findings. The results of the conducted research have revealed that the use of aluminium foam as a fi ller for the gondola car bearing structure components contributes to reduction of their load-bearing capacity from 12 to 47 % compared to the prototype wagon. Originality. The expediency of using aluminium foam as a fi ller of the gondola car bearing structure components by modeling its load-bearing capacity under the most unfavorable operating conditions has been scientifi cally substantiated. Practical value. By reducing the loading on the gondola car bearing structure, using aluminium foam as fi ller for its components, it is possible to increase fatigue strength, reduce the amount of damages, and, consequently, the cost of unscheduled repairs of the wagon. The conducted research can contribute to the creation of recommendations for developing the innovative rolling stock designs with improved technical-and-economic, as well as operational performance. [ABSTRACT FROM AUTHOR]

• Blood-brain barrier is responsible for reduced therapeutic efficacy of drugs. • Literature reports demonstrate excellent ability of nanocarriers in brain delivery. • Nanoemulsion are therapeutically effective for drug delivery in Alzheimer's disease. • Use of effective drug targeting modalities to brain is the need of the hour. Alzheimer's disease (AD) is an irreversible dementia state with characteristic clinical manifestations, including declining cognitive skills and loss of memory, which particularly affects the older population. Despite significant efforts in the field of nano-based drug delivery, there have been few successes achieved in the design of a rational drug therapy. Nanoemulsions (NEs) have potential for the delivery of AD therapeutics owing to their capability for brain drug delivery. Still, there is a long way to go before such therapeutics become a reality in the clinic. In this review, we highlight the preclinical assessment of NEs for AD and discuss the regulatory constraints to their clinical acceptance. [ABSTRACT FROM AUTHOR]

• Survival analysis, is one of the most developed fields of statistics in the last decades of the last century. • Failure prevention methods are necessary and should be adopted for industrial equipment to function well in. • The 75% probability of survival of solid bulk cargo is equivalent to an operational availability time of 444 h. • There is a significant difference between the survival curves of the covariates of shift, types of minerals, number of wagons and tons moved. • The results indicate a significant reduction in the probability of survival of equipment during operation time. In complex industrial systems, the deterioration of equipment and production of defective products are important points that increase the costs inherent to the production function. In this context, the purpose of this article is to estimate the survival of a group of pieces of industrial port equipment known as solid bulk conveyors, thus contributing to decision-making in the maintenance process. To achieve this goal, the Kaplan-Meier method was used to estimate the probability of global survival, and the survival curves were compared using the Log-rank test. To this end, the effect of each covariate on the survival time of the conveyors was analyzed using the Cox regression model, for which an analysis of residuals and influential observations was conducted. The 75% probability of survival of solid bulk cargo is equivalent to an operational availability time of 444 h. It was found that, of the 95 conveyors that were evaluated, 38 (40%) failed and 57 (60%) were censored by the end of the study. The results indicate a significant reduction in the probability of survival of equipment during operation time, as well as a significant difference between the survival curves of the covariates of shift, types of minerals, the number of wagons and tons moved, indicating that these are important predictors in the Cox regression model. [ABSTRACT FROM AUTHOR]

The study presents a mathematical model for the development of an optimal wagon transport plan in conditions of relative uncertainty. It describes an algorithm that allows searching for an optimal railroad-blocking plan in an environment of approximate initial data. The algorithm is based on the branch-and-bound method and fuzzy intervals. An example is provided of how an optimal transport plan for wagon flows given in this way can be determined. [ABSTRACT FROM AUTHOR]

The recent publication of a wagon burial Yasenevyi II 3/10 in the Don River region allows us to compare it with another grave from the same region, Shakhaevskaya II 2/8. These two burials share such important features as the type of the grave, the place of the wagon within the grave, and also the relative positions of both the wagon and the buried people. The latter feature is especially interesting because it turned out to be typical for the Don River region, differing from other wagon burials in pits of the Middle Bronze Age known in other regions of the Northern Caucasus.