BazTech - Yadda

1

Influence of road longitudinal terrain profile on vehicle kinetic energy recovery and mitigation of selected transport negative aspects

Pečman Jan, Stopka Ondrej, Rybicka Iwona, Stopková Mária

Transport Problems

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2023

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T. 18, z. 4

125--133

EN

In recent years, environmental aspects of transport have been at the center of attention for research concerning sustainable development. The most discussed topics comprise vehicle emission production and fuel consumption. These are influenced by many variables and factors. In addition to individual vehicle characteristics and attributes, engine performances, exhaust systems, and their overall construction designs, the terrain and road profile itself have a non-negligible effect on emission production. Road profile parameters can increase or decrease the total vehicle consumption if its potential is utilized correctly. This manuscript discusses the options to reduce road vehicle consumption while accelerating where its velocity is decreased and yet again increased when using the longitudinal terrain profile principle. The physical relations for this subject are presented in the manuscript as well. Based on the data and knowledge achieved, the manuscript then addresses several scenarios in which the fuel consumption of the examined vehicle and an occurrence of certain emission types are examined. Lastly, multiple development trends that can positively affect the specified road vehicle’s negative effects on the environment are described. The novel approach of the conducted research consists primarily of the interdisciplinary connection between road transport planning and vehicle traffic study (i.e., negative environmental aspects resulting from road transport can be mitigated not only by assistant devices installed in vehicles, such as catalytic converters, solid particle filters but also by constructing judiciously designed roads).

2

Changes in the perception of telematics technology by road transport companies: an empirical analysis in 2020-21

Zalewski Wojciech, Osińska Magdalena, Żurek Mirosława

Transport Problems

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2023

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T. 18, z. 1

5--17

EN

We present a novel study concerning the attitudes of road transport enterprises towards a broad application of telematics in operational management in road transportation. The study aims to assess telematics application in road transport and its changes over time while showing the factors most likely to determine the systems’ use. Unobserved categories defined in the technology acceptance model (TAM) are adjusted to measure perceived usefulness, perceived ease of use, and attitudes toward using telematics systems by road transport managers. The study is based on 323 transport enterprises analyzed in two waves in 2020 and 2021. The use of two different time points is motivated by an observed increase in the digitalization of transport documents caused by the COVID-19 pandemic. The empirical findings support the TAM’s usefulness in evaluating IT in transport business management. The findings also reveal that the significantly increased telematics use in 2020 was observed while it was endured. The results are checked for robustness and used for simulations. The study compares managers’ behaviors over time and simulates the effect of individual (observed) variables on unobserved TAM categories.

3

The programmable steering machine for the electric lightweight vehicle

Jemioł Leszek, Wołczyński Zbigniew, Rimkus Alfredas, Smigins Ruslans, Górska Milena, Purtak Mateusz

Journal of civil engineering and transport

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2023

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Vol. 5, No. 1

25--36

EN

In this paper a programmable steering machine (PSM) and the lightweight electric powered vehicle, designed and made at the Kazimierz Pulaski University of Technology and Humanities in Radom (UTH Radom) have been presented. Both these technical objects are the result of the project carried out by the Student Research Group “Turbodoładowani”. The steering machine has been developed with the programmable algorithms allowing to execute a controllable movement of the vehicle steering wheel. After execution, the system does not need an interaction with the driver. For this reason, a higher repetition of the vehicle traction measurements can be achieved. Such confirmation obtained in tests within which the time waveforms of rotation angle of the steering wheel by a set value of 45, 90, 180 and 360 degrees was recorded. In particular, the accuracy index for mentioned test conditions was calculated. Obtained results, expressed by the average value of the sensitivity index were lower than 2% within the tests carried out for ±45 degree maneuvers. In case of other tests i.e., for ±90, ±180 and ±360 degree maneuvers the accuracy index value was lower than 0.3%. In this way, it was confirmed that the tested PSM reached the appropriate operating parameters necessary for vehicle traction tests.

PL

W artykule przedstawiono programowalną maszynę sterującą (PMS) oraz lekki pojazd o napędzie elektrycznym, zaprojektowane i wykonane na Uniwersytecie Technologiczno-Humanistycznym w Radomiu (UTH Radom). Oba te obiekty techniczne są efektem projektu realizowanego przez Studenckie Koło Naukowe „Turbodoładowani”. Maszynę sterującą opracowano z programowalnymi algorytmami pozwalającymi na wykonanie sterowanego ruchu kierownicą pojazdu. Po wykonaniu system nie wymaga interakcji z kierowcą. Z tego powodu można uzyskać większą powtarzalność pomiarów trakcji pojazdu. Potwierdzenie takie uzyskano w badaniach, w których rejestrowano przebiegi czasowe kąta obrotu kierownicy o zadaną wartość 45,90, 180 i 360 stopni. W szczególności obliczono wskaźnik dokładności dla wspomnianych warunków testowych. Uzyskane wyniki wyrażone średnią wartością wskaźnika czułości były niższe niż 2% w badaniach przeprowadzonych dla manewrów ±45 stopni. W przypadku pozostałych badań tj. dla manewrów ±90, ±180 i±360 stopni wartość wskaźnika celności była mniejsza niż 0,3%. Potwierdzono w ten sposób, że badany PSM osiągnął odpowiednie parametry eksploatacyjne niezbędne do badań trakcji pojazdu.

4

Evaluation of the efficiency and corporate social responsibility of the transport industry using the Data Envelopment Analysis method

Horeva Anastasiia, Kapelko Magdalena

Gospodarka Materiałowa i Logistyka

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2023

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nr 3

12--24

EN

Involvement in corporate social responsibility (CSR) is of increasing importance across different economic sectors, including transport industry. This study examines the relationship between CSR and efficiency of companies in the transport industry. It belongs to the type of quantitative research and extends the scope of research related to the subject of CSR and efficiency of companies in the transport industry. Whereas previous literature lacks empirical research analyzing the relation between CSR and efficiency in the transport industry, the present study aims to fill in this research gap. The study focuses on data for 2013–2015 period and on major transport companies in the USA, in particular those representing the air and road transport sectors. The paper is based on Data Envelopment Analysis method which is used to measure efficiency, while the Pearson correlation coefficient is used to detect the relationship between CSR and efficiency. The results confirm positive relationship between CSR and efficiency of transport companies. The paper contains further evidence on the relationship between individual CSR areas (social, environmental and governance CSR) and efficiency. This study can contribute not only as a recommendation for transport companies, but also as an introduction to further and more detailed research of the relation between CSR and efficiency.

PL

Zaangażowanie w społeczną odpowiedzialność biznesu (CSR) nabiera coraz większego znaczenia w różnych sektorach gospodarki, w tym w branży transportowej. W niniejszym artykule zbadano związek pomiędzy CSR a efektywnością przedsiębiorstw branży transportowej. Opracowanie należy do typu badań ilościowych i poszerza zakres badań związanych z tematyką CSR i efektywnością przedsiębiorstw branży transportowej. W dotychczasowej literaturze brakowało badań empirycznych analizujących związek między CSR i efektywnością branży transportowej i właśnie niniejszy artykuł ma na celu wypełnienie tej luki badawczej. Badanie opiera się na danych z lat 2013–2015 i dotyczy czołowych firm transportowych w Stanach Zjednoczonych, reprezentujących sektor transportu lotniczego i drogowego. W artykule wykorzystano metodę Data Envelopment Analysis, która służy do pomiaru efektywności, natomiast współczynnik korelacji Pearsona został wykorzystany do analizy związku pomiędzy CSR a efektywnością. Wyniki badań potwierdzają pozytywny związek pomiędzy CSR a efektywnością firm transportowych. Artykuł zawiera również analizy dotyczące związku pomiędzy poszczególnymi obszarami CSR (społecznym, środowiskowym i ładem korporacyjnym) i efektywnością. Niniejsze opracowanie może stanowić nie tylko rekomendację dla firm transportowych, ale także wstęp do dalszych i bardziej szczegółowych badań nad związkiem między CSR i efektywnością.

5

Modeling the dynamics of changes in CO2 emissions from Polish road transport in the context of COVID-19 and decarbonization requirements

Borucka Anna, Kozłowski Edward

Combustion Engines

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2023

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R. 62, nr 4

63--70

EN

Emissions from transport account for 20-25% of anthropogenic global carbon dioxide emissions [17, 37], with more than 70% coming from road transport, making it an extremely important topic in the context of decarbonization. The aim of the article is to analyze the trend of CO2 generated from road transport, taking into account various sources, and also to examine how reduced mobility during the pandemic affected the emissions at the time. For this purpose, a time series containing observations up to the pandemic outbreak and a time series containing additional observations from the pandemic period were analyzed. For each time series, a trend was determined and described by a polynomial and then verified to see if the pandemic phenomenon significantly affects a parameter of the proposed model, using appropriate statistical tests.

6

Identification of factors increasing the risk of pedestrian death in road accidents involving a pedestrian with a motor vehicle

Macioszek Elżbieta, Granà Anna, Krawiec Stanisław

Archives of Transport

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2023

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Vol. 65, iss. 1

7--25

EN

Walking is a basic form of activity for every human being and has many advantages, including health, economic and environmental benefits. Every journey made using various means of transport begins and ends on foot. As is well known, the group of road users particularly exposed to the risk of serious injury in road accidents, apart from cyclists, also includes pedestrians. These are the so-called vulnerable road users. Pedestrians are a group of road users that is often deprecated by many drivers of motor vehicles, but very important in road traffic. Pedestrian injuries and pedestrian fatalities have enormous social and economic consequences. The problem of high pedestrian risk on Polish roads is well known and has been widely described in the scientific literature last few years. However, the reasons for this state of affairs have not been fully explained, as evidenced by the statistics of road traffic incidents. Despite many studies in this area, the causes indicated in the research often differ depending on the area of analysis, the environment in which the incident took place, location, participants of the incident, environmental conditions, behaviorism and many other features. Therefore, the main goal of the article was to determine the factors influencing the formation of fatalities in road traffic accidents among pedestrians in accidents involving pedestrians and motor vehicles in the Silesian Voivodeship (Poland) in 2016-2021. The logit model presented in the article allowed for the conclusion that the main attributes influencing the increasing the risk of pedestrian death in road accidents involving a pedestrian with a motor vehicle include such features as driving under the influence of alcohol by the driver, exceeding the speed limit by the vehicle driver, when the road incident involves a heavy vehicle (truck, bus), a pedestrian is a male, pedestrian is over 60 years old, is under the influence of alcohol, the incident took place outside built-up area, at night, i.e. from 10:00 p.m. up to 6:00 a.m, in other than good weather conditions. The obtained results can be used in various activities, campaigns aimed at improving the safety of pedestrian traffic in the area of the analysis.

7

Branża TSL w obliczu pandemii Covid-19

Jureczka Kinga

Zeszyty Naukowe Wyższej Szkoły Zarządzania Ochroną Pracy w Katowicach

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2022

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Nr 1(18)

7--13

PL

Od 2020 roku sytuacja społeczno-gospodarcza na świecie była kształtowana przez wydarzenia związane z rozprzestrzenianiem się wirusa COVID-19. Jedną z wielu branż, która została zaskoczona przez COVID-19 jest branża TSL. By lepiej zrozumieć oma wiany temat, na wstępie zwrócono uwagę na różnice definicyjne: transpor– spedycja – lo gistyka. W artykule przedstawiono wybrane problemy, z którymi zetknęła się branża TSL w początkowej fazie pandemii oraz omówiono wybrane rozwiązania cyfrowe, do upowszechnienia których przyczyniła się pandemia.

EN

Since 2020, the socio-economic situation in the world has been shaped by events related to the spread of the COVID-19 virus. One of the many industries that has been taken by surprise by COVID-19 is the TSL industry. To better understand the discussed topic, at first, attention was paid to the differences in definitions: transport – shipping – logistics. The article presents selected problems faced by the TFL industry in the initial phase of pandemic and discusses selected digital solutions, the dissemina tion of which contributed to the pandemic.

8

Bicycle traffic in the cities

Macioszek Elżbieta, Jurdana Irena

Zeszyty Naukowe. Transport / Politechnika Śląska

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2022

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z. 117

115--127

EN

For many years in many Western Europe countries, cycling has been associated with not only recreation and tourism but has equally gained an important function as a means of transport used in everyday commuting to work, study and entertainment. The bicycle appears to be a very good alternative to motor vehicles that produce exhaust fumes and create congestion on road transport networks. Not only is the bicycle environmentally friendly and takes up little space in road transport networks, but also, the time of bicycle travel is often competitive in relation to travel made by private car or public transport. This article presents the characteristics of the bicycle infrastructure and services offered in selected cities in the world and Poland, as well as the issues of bicycle counters as sources of data on bicycle traffic volume, along with an exemplary analysis of this type of data.

9

Initial assessment of the quality of road surfaces

Szczucka-Lasota Bożena, Waligóra Kamil, Węgrzyn Tomasz, Wszołek Łukasz

Zeszyty Naukowe. Organizacja i Zarządzanie / Politechnika Śląska

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2022

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z. 157

571--578

EN

Purpose: The aim of the article is to check the quality of the road and classify the selected road on a four-level scale. Design/methodology/approach: The paper outlines the impact of comprehensive road surface quality management on the safety of vehicles and road users. The basic types of road damage were presented, as well as preliminary diagnostics of a randomly selected national road was carried out. Visual tests were carried out to determine: the type and geometry of the pavement damage, the number of damage, the area covered by the damage. In the article the damage indicators were calculated. The results allowed for the assessment of the quality of the tested pavement and its classification on a four-point scale. Findings: The quality of the road surface was assessed and classified as level C. Research limitations/implications: In the future, it can be suggested to change the methodology of investigate the road. It is proposal to using drone with the application. Practical implications: The research indicates the need to plan the renovation of the road surface and suggests changing the surface material from construction asphalt to the new modified asphalt. Originality/value: The article indicates the need to amend the documents and the current methodology of the procedure.

10

Do telematics technologies help to manage road transport enterprises? Evidence from SME in Poland

Zalewski Wojciech, Osińska Magdalena, Żurek Mirosława

Zeszyty Naukowe. Organizacja i Zarządzanie / Politechnika Śląska

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2022

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z. 157

723--740

EN

Purpose: This study evaluates the acceptance of GPS/GPRS-based telematics technology in freight road transport companies registered in Poland. Design/methodology/approach: The evaluation is based on a survey of 500 representative road transport companies carried out in 2020. The Technology Acceptance Model was estimated, and its results were checked for robustness. The scope of the information collected in telematics systems is defined in terms of its perceived utility and perceived ease of use at the operational management level. The latent factors affecting technology use are defined and implemented. Findings: Most respondents (80%) claimed that telematics systems had a considerable influence on the effectiveness and efficiency of the whole company's operation. It contributed to a higher number of orders executed per time unit, more effective use of the driver's working time, and increased the entrepreneurs' trust in the company. The companies employing more workers recognize the higher usefulness of telematics systems and are motivated to use the technology more widely than smaller enterprises. TAMs estimated separately for small and medium-sized enterprises did not significantly differ among the parameter estimates. Research limitations/implications: The Technology Acceptance Model is a useful analytical tool for evaluating telematics technology acceptance by the road transport sector. The study is based on a random sample of enterprises observed once in 2020. It is recommended to monitor them in two or three waves to compare the dynamics of the telematics usage process. It is planned to continue the study in that direction. Practical implications: The outcomes are valuable in practice twofold. Firstly, the extension of telematics systems use is interesting for final users, i.e., road transport companies that will find scope for their application. Secondly, the results are helpful for system providers who get knowledge on telematics perception from enterprise management. Originality/value: Although widely applied to other IT systems, the TAM model has not been used to evaluate the use of telematics in road transport companies. The paper justifies TAM's categories at the operational management level in road transport enterprises, contributing to understanding managers' behavioral aspects of decision-making.

11

The impact of roadside technical inspections on transport and logistics systems in the Slovak Republic

Hudec Juraj, Šarkan Branislav, Cződörová Renáta, Caban Jacek, Droździel Paweł

Transport Problems

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2022

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T. 17, z. 3

61--73

EN

Road transport safety, apart from environmental protection, is one of the most important tasks for the contemporary world. Annually, about 50 million people are injured in road accidents around the world, of which nearly 1.5 million die as a result. Transport safety consists of many activities and includes various initiatives, including legal changes, training, preventive actions, building safe road infrastructure, and the production of safe vehicles and control systems. This article deals with the issue of performing roadside technical inspections in the Slovak Republic. Specifically, it analyses the results of these oadside technical inspections in individual counties of the Slovak Republic and examines their possible impact on transport and logistics systems in these counties. The correlation analysis showed that the number of checks under the technical roadside inspections is weakly related to the number of logistics centres, but the number of such inspections is moderate in relation to the number of failed vehicles (correlation coefficient = 0.44079). In addition, due to the age of the vehicles, the number of serious and dangerous faults found on them during maintenance inspection increases.

12

Transport drogowy najlepszy do transportu leków

Majowicz Anna

Logistyka

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2022

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nr 3

28--30

PL

Transport medyczny i farmaceutyczny to przemysł lukratywny, ale obciążony dużym ryzykiem i odpowiedzialnością, dlatego jest jednym z najbardziej regulowanych i wymagających rynków transportowych na świecie.

13

Sztuczna inteligencja zamiast spedycji

Mirowski Adrian

Logistyka

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2022

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nr 6

64--67

PL

W dobie zawirowań na rynku energetycznym spowodowanych wojną w Ukrainie, branża transportu drogowego przeżywa trudne chwile, które jednakże motywują firmy do zmian. Koncepcja platformy Snarto zakłada skrócenie łańcucha dostaw poprzez eliminację spedycji oraz zastąpienie jej sztuczną inteligencją.

14

Digitalizacja listów przewozowych w transporcie drogowym to konieczność

Matuszewska Marta

Logistyka

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2022

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nr 4

50--53

PL

Kluczowe znaczenie w przewozie towarów ma list przewozowy, który zawiera wszelkie istotne szczegóły związane z przewozem.

15

Structural design and selected aspects of numerical simulations of a prototype container-platform for intermodal transport

Krasoń Wiesław, Dobrowolski Daniel

Journal of civil engineering and transport

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2022

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Vol. 4, No. 3

57--66

EN

The object of the research is a cheap, easy to build basic module with dimensions corresponding to typical railway containers. Such structures can be used to support the intermodal rail-road transport of wooden and metal logs. The basic structure and one assembled from two or more platforms with various longitudinal dimensions ensures high mobility resulting from the modular structure and the possibility of selecting transport configurations as well as the use of various forms of loading - unloading, including: typical crane operations, the use of forklifts or hook winches. The use of a platform-container will eliminate the need to repeat the operation of individual loading or unloading of each unit of the transported load e.g. a single block of wood, a bundle of bars, as a metal log, a single pipe, during each reloading operation - from the place of logging, production, storage, etc. The paper presents selected problems of the preliminary design and numerical strength tests of a single base module of the platform in a prototype version with dimensional equivalent of a 10'-foot railway container.

PL

W pracy przedstawiono wybrane problemy wstępnego projektowania pojedynczego modułu bazowego platformy, odpowiednika wymiarowego 10’ stopowego kontenera kolejowego w wersji prototypowej. Badania wytrzymałościowe innowacyjnej konstrukcji wspomagane są metodami numerycznymi. Omówiono metodykę takich badań z wykorzystaniem MES i metod multibody MBS, zastosowane modele numeryczne oraz wybrane wyniki symulacji komputerowych odpowiadających krytycznym, najbardziej wytężonym wariantom eksploatacyjnym zastosowań platformy np. do załadunków hakowych.

16

Zróżnicowanie efektywności sektora towarowego transportu drogowego w Unii Europejskiej

Domagała Joanna, Borkowski Maciej

Gospodarka Materiałowa i Logistyka

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2022

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nr 7

24--31

PL

Celem artykułu jest określenie i porównanie efektywności sektorów towarowego transportu drogowego w krajach UE przy wykorzystaniu metody Data Envelopment Analysis (DEA). DEA jest wielowymiarową metodą badania efektywności, umożliwiającą porównanie wielu efektów z wieloma nakładami. W ramach badań obliczono model DEA ukierunkowany na maksymalizację efektów. Jako efekty uwzględniono: przychody sektora transportu drogowego (mln euro) oraz pracę przewozową (tkm), zaś jako nakłady uwzględniono: zatrudnienie (tys. os.); długość sieci drogowej (km); zużycie energii (Mtoe); zarejestrowane pojazdy ciężarowe (szt.). Wyniki badań wskazują, że 10 z 28 badanych sektorów transportu w UE było w pełni efektywnych. Dla sektorów nieefektywnych, bazując na koncepcji benchmarkingu, zaproponowano zmiany w poziomie efektów.

EN

The aim of the article is to use the Data Envelopment Analysis method to determine the efficiency of the road freight transport sectors in EU countries. The DEA method is a multidimensional efficiency tool that allows researchers to compare multiple effects with multiple inputs. As part of the research, the DEA model aimed at maximizing the effects was calculated. The outputs included: turnover of the road transport sector and payload-distance (tonne-kilometers), while the inputs included: employment; length of road network; energy consumption; registered trucks. Research results show that 10 out of 28 analyzed transport sectors in the EU were efficient. For ineffective sectors, based on the concept of benchmarking, changes in the level of effects have been proposed.

17

The process of organisation of abnormal road transport on the example of Poland

Lesiak Gabriel, Szymon Mitkow

Biuletyn Wojskowej Akademii Technicznej

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2022

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Vol. 71, nr 4

15--30

EN

The purpose of the article is to characterise the road transport of abnormal loads and the process of obtaining an abnormal transportation clearance as well as to present a method of supporting transport organisation. The authors undertook to characterise road transport of abnormal loads in light of Polish conditions. The current legal environment in Poland, foreign and domestic literature were used in the research for analysis. The planning process for transport of abnormal load with the analysis of requirements specified was performed in a practical manner. in addition, the successive steps of this process were included on a structured algorithm, showing the steps taken in the research methodology. a detailed analysis showed the complexity of abnormal road transport and the challenges it faces. The experience conducted shows that the process of obtaining an abnormal transportation clearance is time-consuming and involves many institutions working together. an analysis of the requirements for abnormal transport shows the process areas that are bottlenecks. Focusing efforts on their proper organisation can ensure safe preparation of transport and effective management of the entire transportation process. The experience conducted to obtain an abnormal transportation clearance allows us to learn and understand this process, which can be a kind of signpost for those organising such transport without the necessary knowledge. The authors conducted an experiment, applying for a hypothetical abnormal transportation clearance to the General Directorate of national roads and motorways.

PL

Celem artykułu jest scharakteryzowanie drogowego transportu ładunków nienormatywnych w świetle polskich warunków, a także procesu uzyskiwania zezwolenia na przejazd pojazdu nienormatywnego oraz przedstawienie metody wspomagającej organizację przewozu. W badaniach do analizy wykorzystano aktualny stan prawny w Polsce, literaturę zagraniczną oraz krajową. W sposób praktyczny zrealizowano proces planowania przemieszczenia ładunku nienormatywnego z dokonaniem analizy stawianych przed nim wymagań. Kolejne kroki tego procesu zawarto na uporządkowanym algorytmie przedstawiającym działania podjęte w ramach metodyki badań. Szczegółowa analiza pokazała złożoność drogowego transportu nienormatywnego oraz wyzwań, które przed nim stoją. Z przeprowadzonego doświadczenia wynika, że proces uzyskiwania zezwolenia na przejazd pojazdu nienormatywnego jest czasochłonny i angażuje wiele współpracujących ze sobą instytucji. analiza wymagań stawianych transportowi nienormatywnemu pokazuje obszary tego procesu, które są wąskimi gardłami. Skupienie wysiłku na ich właściwej organizacji może zapewnić bezpieczne przygotowanie przewozu i efektywne zarządzanie całym procesem transportowym. autorzy przeprowadzili doświadczenie, występując z wnioskiem o wydanie zezwolenia na hipotetyczny przejazd drogowy pojazdu nienormatywnego do Generalnej Dyrekcji Dróg Krajowych i autostrad. Przedstawiono metodę doboru środka transportowego i zweryfikowano jej działanie na rozpatrywanym przykładzie. Przeprowadzone w praktyce doświadczenie uzyskania zezwolenia na przejazd pojazdu nienormatywnego pozwala poznać i zrozumieć ten proces, co może być drogowskazem dla organizujących przewozy tego rodzaju bez niezbędnej wiedzy.

18

Analysis of the influence of expressway emergencies on transmission speeds and travel delays

Shi Xianfu, Liu Xingliang, Li Menghui, Liu Tangzhi

Archives of Transport

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2022

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Vol. 63, iss. 3

7--21

EN

Expressway emergencies tend to cause traffic congestion, and understanding the travel time delays of on-road vehicles under different combinations of event scenarios and road traffic conditions is valuable for guiding the accurate emergency dispatch services. Most existing studies used methods that combine the Lighthill-Whitham-Richards (LWR) theory and basic traffic diagrams to solve this problem, but the discrete traffic flow characteristics caused by the presence of heavy vehicles have not been considered, thus affecting the applicability of those results to road traffic characteristics in China. Moreover, there is a lack of systematic research on multiple combinations of unexpected event scenarios and traffic conditions, and the guidance value of the previously obtained results is limited. In order to improve the applicability of the prediction model and accurately predict the severity of emergencies, based on a logistic model that is applicable to emergencies, a velocity–density model is constructed to describe discrete traffic flow characteristics. Based on LWR theory, the internal driving force of expressway traffic state evolution under emergency conditions is explored. Combined with real-time traffic flow data, the parameters of the logistic model are calibrated, and a logistic velocity-density model is constructed using a goodness-of-fit test and a marching method, including the free-flow velocity, turning density and heavy vehicle mixing ratio. Thus, the problem that existing models lack applicability to road traffic characteristics in China is solved. Travel time delay is associated with the impact range of an emergency, and it is an effective index for evaluating the severity of emergency incidents. Thus, the travel time delays under different scenarios, different numbers of blocked lanes and different orthogonal combinations of approximate saturation conditions are explored, and the impacts of lane blockage on emergency incidents and travel time delays are obtained. The conclusions show that the presented logistic velocity-density model constructed based on discrete traffic flow characteristics can properly quantify the impact of the presence of heavy vehicles. Additionally, the results can provide theoretical support for handling emergencies and emergency rescues.

19

Comparing the risk management standpoint between the project participants for the urban road transport projects in Hanoi

Toan Nguyen Quoc, Thuy Nguyen Thi, Hai Dinh Tuan, Anh Pham Xuan

Archives of Civil Engineering

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2022

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Vol. 68, nr 2

275--295

EN

The transport system is considered the “backbone” of the urban development. Along with the rapid economic development, the urban road transport system is being paid attention and invested by Hanoi city. By the year 2050, The Hanoi municipal government is expected to complete and hand over for use about 317 urban road transport projects. Due to the high demands of social and economic efficiency, the urban road transport projects in Hanoi face many risks. In which, there are 13 high dangerous risks for the urban road transport project in Hanoi. These risks have the high probability and severity impacted on the outcome of the projects. The project participant’s risk management standpoint will determine the solutions to respond the respective risks, thereby affecting the results of the project. In this paper, the authors compare the risk management standpoint of three main project participants, including owner/project management board, consultant and main contractor/subcontractor. The difference of the risk management standpoint is shown clearly by the project participants’ assessments of 13 high dangerous risks.

20

Towards a sustainable transport in Algeria: the requisite of energy transition in the road transport sector

Chetta Saif Eddine, Nait Amar Nadra

Zeszyty Naukowe. Transport / Politechnika Śląska

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2021

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z. 112

33--49

EN

Less than ten years ago, Algeria embarked on an energy transition with the objectives of sustainable development. Although it concerns all economic sectors, efforts made in the field of road transport, as the main polluter and energy consumer at the national level, are far from being sufficient despite its inclusion in policy statements. This sector is operational exclusively on fossil and exhaustible energies whereas its atmospheric pollutants and gaseous emissions are highly harmful to the environment, public health and the economy. Thus, this paper points out the emergency of an energy transition in the road transport sector to clean and renewable energy as a necessity rather than a choice. It highlights, first, the characteristics of the Algerian automobile fleet and its various impacts and damages on the environment, public health and the economy. Furthermore, it evaluates the various policy initiatives towards sustainable transport and their deficiencies. Hence, the right attitudes and regulatory instruments towards sustainable transport in Algeria are recommended.