Metastasis of adrenocortical carcinoma to the heart

Not required for Clinical Vignette

25 kV AC railway line within 3 kV DC infrastructure in Poland – analysis of operating conditions

Electrified transport is strongly assorted, due to long term development and use of diversified solutions, particularly in the scope of electrical engineering considering the following aspects: nominal voltage of a power supply system, vehicles’ main circuits and electrical drives. The problem of compatible work of varied railway systems in mutual interaction regions, despite of various studies, still appears a significant issue. The main purpose of the paper is to present the negative impact of mutual interaction of AC DC railway regions on the electrified railway lines and power grid. A Matlab – Simulink model of the DC and AC traction systems has been developed. In the article, apart from the main problems which could appear in the AC-DC transition zones, the voltage unbalance analysis caused by the AC traction substation is covered and the influence of asymmetric input voltage of the rectifier traction substation on the DC voltage quality is analysed

The graphic method of sizing pipe reservoir for short, high-intensity rainfalls

Grafi czna metoda wymiarowania zbiornika rurowego dla krótkotrwałych, intensywnych opadów. Wymiarowanie zbiornika retencyjnego w celu zredukowania maksymalnych odpływów z kanalizacji deszczowej jest jednym z podstawowych zagadnień w inżynierii wodnej i lądowej. W artykule zaprezentowano metody wyznaczania optymalnej pojemności zbiornika rurowego. Zastosowanie uproszczonego modelu przepływu pozwoliło na powiązanie parametrów zbiornika rurowego (średnica komory akumulacyjnej, średnica otworu spustowego i współczynnik wydatku) i hydrogramu dopływu (czas przyboru, przepływ maksymalny podczas kulminacji, objętość fali, współczynnik asymetrii fali). Na podstawie uzyskanej zależności funkcyjnej sporządzono nomogramy pozwalające określić wymiary zbiornika i zapewnić redukcję przepływu maksymalnego na dopływie. Wykorzystanie zaproponowanej metodologii przedstawiono na prostym przykładzie obliczeniowym

Advances in Electric Traction System—Special Issue

Transportation does not produce goods by itself but is a service of moving people or goods that allows societies to thrive and develop [...

Power supply of trams in Poland – current state and perspectives of development

Sustainable development of agglomerations requires efficient and ecological transport systems, i.e. electrified transport. In order to achieve the required results of operation of electrified urban transport, especially energy efficiency, it is required to closely examine the existing power supply systems. The biggest share of urban traction systems in Poland belongs to tram systems (in 15 agglomerations and cities). Recent years have witnessed an increased interest in modernisation of the existing lines and construction of new ones. Enhancement of RAMS (Reliability, Availability, Maintainability, and Safety) and energy efficiency of supply systems is a necessary requirement, due to fact that new, modern tram rolling stock with higher power poses significant challenge for the existing, in many systems, old power supply infrastructure. Furthermore, due to low driving-range of autonomous vehicles equipped with batteries and a need of frequent charging of storage devices, catenary supplied urban transport will dominate in the areas of its use. In addition, it might be helpful in developing hybrid vehicles supplied both from a catenary and from energy storage devices (charged during run under catenary) on sections without catenary. The paper presents parameters characterizing tram power supply systems in Poland. The analyses carried out for many tram lines have shown that even at relatively low investments for modernisation of the tram power supply system, it is possible to obtain fast return (energy saving due to improvement of efficiency of recuperation and the resulting reduction of CO2 emission). Other advantages of modernisations include: enhancement of standards in supply of modern trams with higher power and improvement of reliability due to the reduced risk of disturbances and damages

Power supply of trams in Poland – current state and perspectives of development

Sustainable development of agglomerations requires efficient and ecological transport systems, i.e. electrified transport. In order to achieve the required results of operation of electrified urban transport, especially energy efficiency, it is required to closely examine the existing power supply systems. The biggest share of urban traction systems in Poland belongs to tram systems (in 15 agglomerations and cities). Recent years have witnessed an increased interest in modernisation of the existing lines and construction of new ones. Enhancement of RAMS (Reliability, Availability, Maintainability, and Safety) and energy efficiency of supply systems is a necessary requirement, due to fact that new, modern tram rolling stock with higher power poses significant challenge for the existing, in many systems, old power supply infrastructure. Furthermore, due to low driving-range of autonomous vehicles equipped with batteries and a need of frequent charging of storage devices, catenary supplied urban transport will dominate in the areas of its use. In addition, it might be helpful in developing hybrid vehicles supplied both from a catenary and from energy storage devices (charged during run under catenary) on sections without catenary. The paper presents parameters characterizing tram power supply systems in Poland. The analyses carried out for many tram lines have shown that even at relatively low investments for modernisation of the tram power supply system, it is possible to obtain fast return (energy saving due to improvement of efficiency of recuperation and the resulting reduction of CO2 emission). Other advantages of modernisations include: enhancement of standards in supply of modern trams with higher power and improvement of reliability due to the reduced risk of disturbances and damages

Analysis of Input Impedance of the Traction Vehicle with DC Chopper as a Function of Operation Mode

A problem of analysis of the input impedance of a converter traction vehicle is presented in the paper. The value of input impedance of a traction vehicle has significant influence of compatibility between track circuits and traction vehicles. The model of chopper controlled DC series motor vehicle was implemented as a simulation model including all significant parameters of the whole system: substation-catenary-input filter-chopper. Exemplary results of analysis of the specific locomotive EM10 are included. The results both of analytical and simulation approach for low frequency input impedance computations were compared

Modelling of operation of a stationary energy storage device in metro rail transport for selection of its parameters

The paper presents a Simulink model of a DC metro traction supply system with a stationary energy storage device (SESD). The simulation model consists of traction substations, a train model, and an energy storage device (ESD) with supercapacitors (SC). A new energy management strategy considering the line voltage and current, SC state of charge (SOC) and SC charging and discharging current is proposed. This method can improve the energy savings and manage the remaining energy. Simulation results provided in this paper justify the control method. The proposed model can be used with different ESD, such as batteries