Development of road infrastructure and the legitimacy of changing the method of assembly of road construction elements with the use of vibration isolation

PURPOSE: Due to the constantly progressing development of road infrastructure, which is very important in Poland, it is necessary to look at the possibilities of improving the quality of assembly of individual elements of the road structure. The main problem that negatively affects individual structures is the problem of vibrations transmitted from means of transport to the road. By performing specialized tests before assembly, we are able to assess the amount of vibrations in a specific area of the road. The paper presents the methods that were used in this type of research and the possibilities of using the above-mentioned methods. onroad assembly tests.DESIGN/METHODOLOGY/APPROACH: The authors conducted a series of tests using modern sensors allowing for precise indications of vibrations in the studied area. Then, taking into account the tests of vibro-isolating materials, they had the opportunity to properly select them for individual road construction elements.FINDINGS: As a result of the research, it is possible to minimize damage from means of transport to individual road construction elements and the roads themselves.PRACTICAL IMPLICATIONS: The proposed solutions are different from those available on the market, and make it possible to control damage to roads, and even prevent them to a fairly large extent, which has an impact on extending the quality of repairs. According to the authors, performing tests in individual areas is necessary before installing road structural elements, as it extends their service life.ORIGINALITY/VALUE: The use of original solutions not available on the market. They allow you to fully assess the correctness of the work performed and prevent future damage caused by vibrations.peer-reviewe

Asymmetric threats in terms of safety of railway systems

This article deals with the problem of new threats that appear in areas that have not been affected by them so far. The considerations concern asymmetric threats and the railway system. The analysis of this issue was carried out on the basis of general information on the problem of asymmetric threats and the knowledge of the railway system, its operation and identified threats that can be attributed to the characteristics of asymmetric threats. The aim of the article is to draw attention to new phenomena that are beginning to affect transport on a global basis, including rail transport

Electric Drive Solution for Low-Floor City Transport Trams

The urban transport system based on trams as the basic means of transport is one of the oldest systems of human transport in urban agglomerations. A tram is a more efficient, cheaper-to-operate, and greener means of transport compared to a bus. Striving to enable the use of this means of transport by elderly and disabled people, constructors and manufacturers of tram vehicles began to consider the requirements of the ordering parties—organizers of municipal public transport—in their solutions. The basic condition for disabled and elderly people to use tram transport is the possibility of safe and efficient entry and exit from the vehicle at tram stops. The fulfillment of this condition is possible only in the case of tram vehicles with a low 100% floor, and this, in turn, requires the replacement of trolleys with traditional wheelsets, that is, trolleys with independently rotating wheels, in the construction of the running gear. A wheelset with independently rotating wheels (IRW) does not have self-centering properties, and, thus, problems may arise with excessive wear of wheel and rail profiles and with continuous contact of the wheel flange with the rail, which may, consequently, lead to derailment. Driving a vehicle on the track in this case is governed by different laws. To prevent such phenomena, it is required to use the wheel drive control system, which allows for the stabilization of the vehicle movement on the track. Both the introduction of independently rotating wheels in the construction of the bogie and the drive connected to the wheel control system requires research and analysis to confirm the correctness of the assumptions made. The innovative solution of the control system in the case of a tram vehicle was patented and then the patent was implemented to produce a low-floor tram with 100% low floor by a Polish tram manufacturer. This article presents the results of the work carried out on the adoption of the concept of a running gear and drive solution for a low-floor tram vehicle with independently rotating wheels and the results of simulation analysis of the drive control of such a system, using mathematical models of the mechanical system (running gear) and the electrical system (motor drive control system)

Petrography of glacial tills in the szczerców out crop, central poland – problems of stratigraphic interpretation

The pa per pres ents re sults of petrographic anal y ses of gla cial tills in the west ern part of the Kleszczów Graben and the at tempt of their strati graphic in ter pre ta tion. Petrographic co ef fi cients have al lowed the iden ti fi ca tion of five till lithotypes: T1, T2A, T2 and T2B – as signed to the South Pol ish Com plex (Elsterian) and T4 cor re lated with the Mid dle Pol ish Com plex (Saalian). The well-ex pressed tills that rep re sent the South Pol ish Com plex, oc cur at the bot tom of the sec tion. A new till lithotype, T2B, has been dis tin guished, cor re spond ing to the Kuców For ma tion. It sup ple ments the Pleis to cene lithostratigraphic sec tion of cen tral Po land and cor re sponds to the Sanian 2 Gla ci ation. Among the younger tills, the T4 one (Odranian Gla ci ation) is well de vel oped. The up per most tills of the Wartanian cold stage have been re duced by glaciofluvial and flu vial ero sion. It is, to some ex tent a con se quence of the ex is tence of a de pres sion in this area, called the Szczerców Ba sin. The pa per high lights the in ter pre ta tional dif fi cul ties con cern ing the rank and the num ber of ice sheet ad vances dur ing the Pol ish and Mid dle Pol ish Com plexes in cen tral Poland

Gene expression profiling of blood in ruptured intracranial aneurysms : in search of biomarkers

The molecular mechanisms underlying the systemic response to subarachnoid hemorrhage (SAH) from ruptured intracranial aneurysms (RAs) are not fully understood. We investigated whether the analysis of gene expression in peripheral blood could provide clinically relevant information regarding the biologic consequences of SAH. Transcriptomics were performed using Illumina HumanHT-12v4 microarrays for 43 RA patients and 18 controls (C). Differentially expressed transcripts were analyzed for overrepresented functional groups and blood cell type-specific gene expression. The set of differentially expressed transcripts was validated using quantitative polymerase chain reaction in an independent group of subjects (15 RA patients and 14 C). There were 135 differentially expressed genes (false discovery rate ⩽1%, absolute fold change ⩾1.7): the abundant levels of 78 mRNAs increased and 57 mRNAs decreased. Among RA patients, transcripts specific to T lymphocyte subpopulations were downregulated, whereas those related to monocytes and neutrophils were upregulated. Expression profiles of a set of 16 genes and lymphocyte-to-monocyte-and-neutrophil gene expression ratios distinguished RA patients from C. These results indicate that SAH from RAs strongly influences the transcription profiles of blood cells. A specific pattern of these changes suggests suppression in lymphocyte response and enhancements in monocyte and neutrophil activities. This is probably related to the immunodepression observed in SAH