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The wheel set of a rail vehicle with a disc brake is the basic assembly of a rail vehicle exposed to abrasive wear. From the operational point of view, the wear process of the wheels and brake discs is uneven, which for the carrier involves switching off the vehicle, once when the maximum wear of the discs is reached and again when the wheels wear out. The process of both untying the wheel set from the bogie, dismantling the wheels and discs from the axle is a time-consuming and expensive process, which consequently affects the exclusion of the vehicle from planned traffic. In the article on the basis of brake disc wear results, 3 concepts of bogie management were proposed. The first concerns the bogie rotation, the second and third concepts concern the exchange of bogies with and without rotation. Using the MUZ multi-criteria programming method, the concepts were evaluated and the best one was selected taking into account the evaluation criteria. The aim of the article is to present concepts that reduce the wear of discs brake systems in a multi-unit traction unit using bogie migration under the vehicle. [ABSTRACT FROM AUTHOR]

The article presents the results of thermovision tests of the disc brake and the drive system components located in its vicinity on the 111Ed electric locomotive in field conditions. For this locomotive, tests were carried out on a test track to measure the temperature of the disc and the temperature of other devices that were installed close to the brake disc. These tests were performed pointwise, i.e. before and after the test, and continuously throughout the braking process. The article presents the methodology of thermal imaging research and the preparation of the camera for outdoor research with objects with different emissivity. Due to the rotating brake disc, it was decided to measure using an IR camera because measurements using thermocouples were very difficult and complex. In exceptional situations, temperature measurement using thermocouples is used, but it requires an extensive additional measurement system and signal recording, which is more expensive. Correct configuration of the IR camera to real conditions is extremely important because it directly translates into the increase in measurement error. [ABSTRACT FROM AUTHOR]

Due to their wide range of friction characteristics resulting from the application of different friction materials and good heat dissipation conditions, railway disc brakes have long replaced block brakes in many rail vehicles. A block brake still remains in use, however, in low speed cargo trains. The paper presents the assessment of the braking process through the analysis of vibrations generated by the components of the brake system during braking. It presents a possibility of a wider application of vibroacoustic diagnostics (VA), which aside from the assessment of technical conditions (wear of brake pads) also enables the determination of the changes of the average friction coefficient as a function of the braking onset speed. Vibration signals of XYZ were measured and analyzed. The analysis of the results has shown that there is a relation between the values of the point measures and the wear of the brake pads.

The article presents an overview of the construction of automatic couplers and their digital version of the DAC for freight wagons. In the article, particular attention was paid to the process related to the development and popularization of the design of automatic digital couplers in the European Union countries. Poland, the automatic coupler train was presented in July 2022 and tested under various conditions. This is related to the current trend of improving rail safety and accelerating the procedure of forming trains, and, consequently, sending a freight train on its way. Automatic digital couplers will allow, in addition to mechanical connection, also pneumatic and electrical connection without the participation of an employee for coupling and uncoupling carriages. [ABSTRACT FROM AUTHOR]

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The article presents a new method for the evaluation of the braking process through analysis of the braking vibration during braking to stop with a permanent the analysis of temporal signals of vibration acceleration in the frequency domain. The problem of research assembled in the article was determined by estimating the braking process one value of the diagnostic parameter of the vibration signal generated by the disc braking level set during braking. [ABSTRACT FROM AUTHOR]

Attempt to raise train speed involves application of greater braking power i.e. braking systems rapidly absorbing and dispersing stored heat energy. To maintain high efficiency of braking system in the whole operational process, it is necessary to control the friction set: brake and pad before reaching limit wear particularly of friction pads. Few disadvantages of disc brake include a lack of possibility of controlling the condition of the friction set: brake and pad in the whole operation time. It is particularly observable in rail cars, where disc brakes are mounted on the axle of the axle set between the wheels. To check the wear of friction pads and brake discs it is necessary to apply inspection channel to carry out inspections, and to carry out replacement of friction parts in case they reach their terminal wear. The purpose of this research is to apply frequency analysis to evaluatnion of the wear of friction pads on the base vibration signal generated by caliper with pads disc brake lever set. [ABSTRACT FROM AUTHOR]

The purpose of this article is to analyse results of research on behaviour of average temperature obtained from the measurement of railway brake disc using thermographic camera. The article presentes the distribution of average temperature on elements such as brake discs, braking pad and caliper railway disc brake. Observation of temperature on these elements, by the thermographic camera has allowed to determine the temperature distribution for braking stop with new pad and wear friction pad. Then on the basis of recorded images and thermography analysis developed model thermomechanic to determine the temperature of three elements of the railway disc brake, depending on the wear of friction pads. [ABSTRACT FROM AUTHOR]

The Hsp90 molecule, one of the most abundant heat shock proteins in mammalian cells, maintains homeostasis and prevents stress-induced cellular damage. Hsp90 is expressed under normal conditions at a level of about 1-2 Percent of total proteins, while its expression increases 2-10 fold in cancer cells. The two main constitutively expressed isoforms of Hsp90 are known as Hsp90-alpha and Hsp90-beta, and their upregulation is associated with tumor progression, invasion and formation of metastases, as well as development of drug resistance. The Hsp90 is a key target for many newly established, potent anticancer agents containing Hsp90 N-terminal ATP binding inhibitors, such as geldanamycin, and its analogues 17AAG and 17DMAG. The therapeutic usage of geldanamycin has been limited due to its poor water solubility and severe hepatotoxicity. Therefore, its analogues, including 17AAG, 17DMAG, Tanespimycin and Retaspimycin hydrochloride, with improved pharmacokinetic profiles, have been developed.