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1

Study of the possibility of using transmission in the lte system on a selected railway line for the purpose of running railway traffic

Chrzan Marcin

Archives of Transport

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2021

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Vol. 57, iss. 1

91--101

EN

The railway and the Rail Traffic Control Systems installed on it in Poland have recently experienced rapid technological development. This is undoubtedly due to the funds that Poland receives from the European Union for the modernization of railway infrastructure. The development of modern railway infrastructure means not only stations, modern rolling stock, but also safe and reliable train control systems based on the latest telecommunications and information technologies. For a longer time, radio communication based on the GSM-R (GSM for Railways) standard is being introduced on PKP. For this purpose, dedicated infrastructure is being built in order to use this technology for railway traffic. This is associated with huge investment costs. Since the beginning of its existence, research has been conducted worldwide on the use of LTE (Long Term Evolution) technology for conducting railway traffic. For economic and technological reasons, it is necessary to study other possibilities of using modern telecommunications infrastructure not yet dedicated to railway tasks in these open networks. The article will present research on the use of open radio communication network based on LTE standard for rail traffic and passenger comfort. It will discuss the research method and selected results of measurements made on railway line no. 4. The choice of this railway line was dictated by two factors. The first one resulted from the maximum train speed, the second one is the variety of rolling stock used on this line (compartmental and non-compartmental wagons). The part of research concerning collection of measurement material was performed within the framework of completed research work PBS3/A6/29/2015. As a result of conducted in-depth literature analysis as well as performed measurements and calculations, it allowed to develop a model and software for simulating system operation in real conditions. This system allows to send railway telegrams on appropriate safety level defined in standardization documents. The research proved the possibility of using an open system in the LTE standard for the transmission of signals for railway traffic control and passengers while maintaining an appropriate level of safety. The only limitations which were indicated by the tests are improper radio interface coverage of railway lines. Appropriate planning of radio coverage of railway areas by radio communication operators (so far ignored) with proper cooperation of infrastructure manager can lead to launching efficient communication system without necessity to build specialized infrastructure for railway.

2

The principle of minimum entropy production for diffusion and heat transfer in open systems

Bujakiewicz-Korońska R., Koroński J.

Czasopismo Techniczne. Nauki Podstawowe

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2011

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R. 108, z. 1-NP

23-35

EN

Equilibrium thermodynamics describes a closed system that tends towards an equilibrium characterized by minimum energy and maximum entropy. Non-equilibrium thermodynamics describes an open systems that tends towards a steady state characterized by minimum production of entropy. The open systems are systems which are not isolated systems, i. e. systems which exchange as well as the mass (molecules) and any other form of energy with surroundings. The energy delivered to the system from its surroundings is dissipated into new structures. These structures are called dissipative structures or shortly: patterns. In particularly soil-plant systems exchange both energy and matter with their surroundings and are consequently examples of open biological systems. They should therefore tend towards a steady state described by non-equilibrium thermodynamics and characterized by minimum production entropy. In this paper we study the principle of minimum entropy production for diffusion and heat transfer in open systems. The general formulae and exemplary values of entropy production for diffusion and heat transfer for any substances involving particular boundary conditions are obtained.

PL

Równowaga termodynamiczna cechuje układy zamknięte (izolowane) w takim sensie, że tendencja do równowagi charakteryzuje się stanem minimum energii i maksimum entropii w układzie. Nierównowaga termodynamiczna cechuje układy otwarte dążące do stanu minimum produkcji entropii. Poprzez układy otwarte rozumiemy układy, które nie są układami izolowanymi, tzn. układy, które wymieniają z otoczeniem masę (cząstki) i inne formy energii. Energia wymieniana z otoczeniem jest dyssypowana na nową strukturę. Takie struktury powstałe w układach otwartych nazywa się strukturami dyssypatywnymi lub krótko patterns. W szczególności rośliny wymieniają z otoczeniem energię i masę i są w konsekwencji przykładami otwartych układów biologicznych. Zatem wykazują tendencję do nierównowagi termodynamicznej i dążą do stanu minimum produkcji entropii. W niniejszym artykule badamy zasadę minimum produkcji entropii dla procesu dyfuzji i przewodnictwa cieplnego w układach otwartych. Uzyskujemy ogólne formuły i przykładowe wartości produkcji entropii w układach otwartych dla procesu dyfuzji i przewodnictwa cieplnego dla dowolnych substancji przy spełnieniu pewnych szczególnych warunków brzegowych.

3

The summary increment of an entropy in open systems in which proceed opposite processes

Pelińska-Olko E.

Systems : journal of transdisciplinary systems science

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2008

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Vol. 13, spec. iss. 1/2

59--65

EN

The entropy is the important thermodynamic function in help which we can obtain "goodness" of the both right-way and left-way cycles. The concept of the efficiency of the ideal cycles mentioned above is often used in technique. This paper is connected with the summary increment of the entropy obtained for the mutually opposite processes, for example in open systems solid body -its gaseous neighbourhood. The mutually opposite processes are defined as the processes proceeding in the some temperature ranges but in the opposite directions fig.2. It is proved that the summary increments of an entropy are for a cooling higher than in case of a heating, additionally their difference growth with the growth of a temperature range. It is introduced the concept of the relative increment of en entropy for the mutually opposite processes, which could have the significance for a industry.

4

Ripples in a Pond: An Open System Model of the Evolution of Safety Culture

Morley F. J. J., Harris D.

International Journal of Occupational Safety and Ergonomics

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2006

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Vol. 12, No. 1

3--15

EN

The development of an effective safety culture is essential to promote safe operations. Previous studies have either identified the characteristics of effective safety culture analytically, inferring them from signs and symbols derived from working practices, or have restricted the study of the development of safety culture to workers within an organisation. This paper describes a large-scale survey-based study in which the factors influencing the evolution of safety culture are identified empirically and, drawing upon open systems theory, are also extended beyond the bounds of the organisation. Three major determinants of safety culture are identified: safety concerns, influences and actions. Sub-components within each of these categories are also identified and the relationship between them is hypothesised.

5

An assessment of a possibility of application of modern adjustment methods in underwater navigation

Felski A., Wiśniewski Z.

Reports on Geodesy

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2004

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nr 2/69

359--368

EN

In the recent years it has been observed the constant rise of usage of underwater submerged vehicles (UV) for non-military purposes. The authors present general concepts of estimation of underwater vehicle position which may be applied in the investigated problems. The basic scope of their application and possible development directions will be also indicated.

6

Obserwacje nadliczbowe w ilorazowym systemie nawigacyjnym jako czynnik zwiększający dokładność systemu w układzie otwartym

Czaplewski K., Wiśniewski Z.

Zeszyty Naukowe Akademii Marynarki Wojennej

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1999

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R. 40 nr 3 (140)

19-28

PL

W pracy przedstawiono zastosowanie obserwacji nadliczbowych do zwiększenia dokładności pozycji obserwowanej jednostki na morzu. Przedstawione badania przeprowadzono wykorzystując hipotetyczny system nawigacyjny, którego parametrem nawigacyjnym jest iloraz odległości. Badania mają charakter rozpoznawczy i są ograniczone do elementarnego przykładu.

EN

The paper presents employment of supernumerary observations to increase position accuracy of an object at sea obtained by observation. The investigations presented were carried out with a hypothetical navigational system whose navigational parameter is constituted by a distance quotient. The investigations are of reconnaissance character and are limited to an elementary example

7

System łączności z integracją usług dla potrzeb dowodzenia i kierowania

Różański G., Radzikowski W., Łysek K.

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

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1998

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nr 11

770-773

PL

Opisano wybrane problemy projektowania systemów z integracją usług przeznaczonych do celów wojskowych. Przedstawiono przykładową koncepcję systemu łączności z integracją usług dla potrzeb dowodzenia i kierowania.

EN

The article describes selected problems of designing integrated systems for military purposes. Integrated Services Communication System for command and control purposes was described.

8

Inteligencja w sieci

Gys L., Zuidweg H.

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

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1998

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nr 7

479-485

PL

Omówiono rolę sieci inteligentnych (IN) jako środka umożliwiającego realizację usług sieciowych. Przypomniano w nim architekturę leżącą u podstaw tej koncepcji oraz wybrane usługi, oferowane obecnie przez działające systemy. Omówiono także zagadnienia przekształcania platformy IN w system otwarty, niezależny od infrastruktury sprzętowej.

EN

The paper presents the inteligent network (IN) as an easy and powerful solution supporting the need for new value-added services. The architecture of IN is briefly reminded and some of the services offered in today's IN systems are described. The paper also discusses the future of IN platform, tuning into the open solution by using new information technology achievements.