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PL
W niniejszym artykule podjęto analizę wielkości popytu efektywnego na rynku przewozów pasażerskich w Unii Europejskiej ze szczególnym uwzględnieniem przewozów realizowanych kolejami dużych prędkości na podstawie rocznych statystyk opublikowanych przez Eurostat. W badanym okresie, tj. w latach 2000–2015, w Unii Europejskiej praca przewozowa pociągami dużych prędkości wzrosła ponad dwukrotnie. W 2015 r. praca ta wyniosła 113,67 mld paskm. Stanowiło to 25,72% pracy przewozowej realizowanej transportem kolejowym na obszarze UE-28. Prawidłowa ocena poziomu popytu na rynku transportu pasażerskiego w UE stanowi istotne zagadnienie z punktu widzenia dostarczania społeczeństwu usług transportowych, dostosowanych do potrzeb i preferencji podróżnych.
EN
This article analyzes the size of effective demand on the passenger transport market in the European Union, with particular emphasis on high-speed rail transport on the basis of annual statistics published by Eurostat. In the analyzed period, i.e. in the years 2000–2015 in the European Union, the work of high-speed trains more than doubled. In 2015, this work amounted to 113.67 billion passes. It constituted 25.72% of transport work carried out by rail transport in the EU-28 area. The correct assessment of the level of demand on the passenger transport market in the EU is a very important issue from the point of view of providing the public with certain communication services, enabling at the same time diversity in its selection.
EN
The paper contains the theoretical and experimental analysis of the impact of the drawing angle on the drawing process and the properties of low carbon steel wires. A multi-stage drawing wire rod with a diameter of 5.5 mm on a wire with a diameter of 1.0 mm has been carried out in two stages. The first one consisted of preliminary drawing wire rod for the wire with a diameter of 2.2 mm which was next subjected to the drawing process at a speed of 25 m/sec at the final wire with a diameter of 1.0 mm. The wires were drawn in conventional dies with drawing angle α = 3, 4, 5, 6, 7 degrees. For the wires drawn in respective variants, the investigation of the mechanical properties was performed and the amount of lubricant on the surface of steel wires was determined. Numerical analysis of the process of drawing in the Drawing 2D complemented the experimental studies. It has been shown that when drawing at high speeds, properly chosen the value of the angle of the working part of the die can improve the lubrication conditions and mechanical properties of steel wires.
EN
In the paper, a novel control method of a switched reluctance generator was discussed. The presented control method allows a rotor rotating at high speed to enter the continuous-conduction mode which causes an increase of generated output power. A control function of the presented method was given as well as simulation and laboratory tests.
4
Content available remote Problem dłuższego przejazdu szybkich pociągów przez stacje
PL
W pracy obliczono wartości niekorzystnego wydłużenia czasu przejazdu pociągów przez stacje na liniach kolejowych dużych prędkości, spowodowane zmianą toru wjazdowego.
EN
In this article the values of adverse extension of time for riding of trains through the stations on the railway lines with high speed, caused by changes of the entry track, are calculated.
Logistyka
|
2015
|
nr 3
3758--3766, CD 1
PL
W referacie przedstawiono modele współpracy rozjazdu kolejowego z napędem dla kolei dużych prędkości na przykładzie rozjazdu zwyczajnego eksploatowanego na stacji Strzałki. W pracy dokonano klasyfikacji przykładowych rozwiązań geometrycznych stosowanych rozjazdów kolejowych w Polsce oraz przyrządów pomiarowych sił przestawiania ruchomych elementów w rozjeździe dużych prędkości. Oceniono obecnie stosowane metody pomiarowe, podjęto badania wtórne nad koniecznością zmian i zastosowaniu nowatorskich rozwiązań technicznych dla skrócenia czasu i zwiększeniu dokładności pomiarów w liniach kolejowych PKP Polskie Linie Kolejowe S.A.
EN
The paper presents models of cooperation between railway turnout and point machine for high speed railways for example, turnout which is operated on Strzałki station. The paper presents the classification of the sample geometries used in railway turnouts in Poland and measuring devices adjustment forces moving parts in high speed turnouts. To judge from the facto of current measurement method, used secondary research on the need of change and the use of innovative technical solutions for time reduction and increase precision of measure in PKP Polish high speed railways.
EN
Variable gain amplifier (VGA) is the key element for amplifying process in analog to digital converter (ADC). In this paper, a low voltage and wide bandwidth class AB VGA is designed using CEDEC 0.18-μm CMOS process for high speed applications. The result show that, the designed VGA has a wide bandwidth of 100-MHz and consumes power less than 125uW at 1V supply voltage. From the results it is also evident that the circuit is capable of working with high linearity and wide bandwidth. The frequency response (Gain) and the wide bandwidth of this class AB VGA is better than previously reported class AB VGA. Smaller transistors are used to make the chip small and it occupies only 0.003 μm2. Such a VGA is suitable for high-performance RF devices.
PL
W artykule opisano niskonapięciowy, szerokopasmowy wzmacniacz klasy AB typu VGA (variable gain amplifier – wzmacniacz o zmiennym wzmocnieniu). Wzmacniacz zaprojektowano wykorzystując proces 0.18 um CMOS. Wykonano wzmacniacz o pasmie 100 mHz i poborze mocy mniejszym niż 125 uW przy napięciu zasilania 1 V.
EN
In order to identify high-speed navigation ability of trimaran planing hull, as well as investigate the characteristics of its resistance and hull form, ship model tests were conducted to measure resistance, trim and heaving under different displacements and gravity centre locations. The test results were then used to study the influence of spray strips on resistance and sea-keeping qualities. Moreover, different planning surfaces were compared in the model tests which helped to look into influence of steps on hull resistance and its moving position. Also, the resistance features of monohull and trimaran planing hulls, both with and without steps, were compared to each other. From the tests it can be concluded that: the two auxiliary side hulls increase aerodynamic lift at high-speed motion, which improves the hydrodynamic performance; the trimaran planing hull has also excellent longitudinal stability and low wave-making action; when Fr∇> 8, its motion is still stable and two distinct resistance peaks and two changes of sailing state (the second change is smaller) appear; spray strips are favourable for sea-keeping qualities at high speed. The change trends before the second resistance peak as to the resistance and sailing behaviour of trimaran planing hull without steps are the same as for monohull planing hull without steps. but when steps in both hulls exist the change trends are different; more specifically: trimaran planing hull with steps has only one resistance peak and its resistance increases along with its speed increasing, and the resistance is improved at the increasing speed as the number of steps increases.
8
Content available remote Podłoże toru na liniach kolei dużych prędkości
PL
W artykule charakteryzowano oddziaływania pojazdów i zjawiska z nimi związane, występujące w warunkach ruchu z dużymi prędkościami na liniach z nawierzchnią klasyczną i niekonwencjonalną, układanych na podtorzu gruntowym i konstrukcjach obiektów inżynieryjnych. Wskazuje na wady i zalety stosowanych rozwiązań.
EN
The paper deals with vehicle - railway track interaction and connected phenomena in the high speed traffic, regarding both classical and unconventional superstructure based on subgrade or engineering objects. Advantages and weaknesses of various solutions are discussed.
EN
In this paper a non-salient field winding for a brushless synchronous generator working with high speed in an autonomous energy generation system (e.g. airplane power grid) has been presented. A conception of a six-pole cylindrical-rotor with distributed field winding has been proposed. Comparison study of salient and prototype non-salient field winding has been carried out. Chosen simulation and measurement results of the generator stator voltage and current waves have been presented.
10
Content available remote Wstępny model strefy przejściowej
PL
W artykule przedstawiono propozycję modelu strefy przejściowej pomiędzy nawierzchnią bezpodsypkową a nawierzchnią podsypkową. Jest to model dynamiczny, w którym obciążenie stanowi skupiona siła pionowa poruszająca po torze. Ruch nawierzchni opisano przy pomocy liniowego równania różniczkowego cząstkowego o zmiennych współczynnikach. Równanie rozwiązano metodą różnic skończonych oraz przeprowadzono szereg obliczeń wpływu sztywności i tłumienia na wielość ugięcia szyny. Oszacowano także siły dynamiczne na styku koło-szyna. Rozważano dwa przypadki konstruowania strefy przejściowej: z dodatkowymi szynami wewnętrznymi oraz bez nich.
EN
In the paper, a preliminary model of the transition zone between ballasted and ballastless tracks has been presented. It is a dynamic model consisting of a concentrated moving load along the track and a linear beam resting on a linear foundation with damping. The motion of the beam has been described using a partial differential equation with variable coefficients. The equation has been solved using the finite difference method. Some preliminary calculations have been carried out. The influence of the stiffness and damping on the vertical rail deflection has been taken into account. Two cases of the transition zone have been calculated: with and without additional rails between the bearing rails.
11
Content available remote High Speed Steel Rolls
EN
The importance of quality of rolls for hot rolling is very high in this time. The main attributes of the rolls are wear resistance and hardness. In this case we consider and realize the development and production of HSS rolls, which have strongly better qualities than e.g. High Chromium (Hi-Cr) or Ni-grain rolls.
12
Content available remote Experimental investigation of a high speed centrifugal pump
EN
Usually, the normal rotational speed of pumps is defined by the electric drive system and the frequency of the power supply. It is the objective of this paper to investigate the correlation between pump efficiency and rotational speed. The design of the particular, single stage, centrifugal pump and the test facility for the investigation of pump hydrodynamics with increasing rotational speed are presented in this paper. The original impeller design duty speed is 2850 rpm. Pump characteristic measurements of this impeller were performed for a speed range up to 9.000 rpm and it turned out that the best static pump efficiency at 9000 rpm is 3.7 % higher than the efficiency at 2000 rpm.
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