Journal of Sustainable Development of Transport and Logistics

An empirical study of air transport demand forecast in Nigeria

2023-03-15T12:14:31+02:00

The aim of the study is to estimate the air travel demand forecast of domestic passengers’ travels in Nigeria from 2002-2016. Data wesourced from Central Bank of Nigeria, National Bureau of Statistics, and Federal Airport Authority of Nigeria. The study utilized multiple regressions model using Stata-Graphic software solver to analyze the data. From the analysis, the result shows that there is significant relationship between the explanatory variable (passengers) and unexplanatory variables National Disposable Income, Population, Average Airfare, Gross Domestic Product, Exchange Rate, Total Expenditure, and Crude oil price, accounted for adjusted R of 93.624% relationship with demand for domestic air travel of passenger. The R-square statistic shows that the fitted model explains the variability in Number of passenger (NPAX) which is 96.8124%. The Hypothesis testing reveals that National Disposable Income and Air fare have strong statistically significant relationship with the demand for domestic air travel with P-value of 0.0013. Moreso, there is statistically significant relationship for National Disposable Income, Average Airfare, and Crude oil price with P-value of 0.0017 and 0.0445 respectively. Furthermore, forecast of the number of passengers and average airfare was carried out using ARIMA (1,0,0) model which made available the future predicted values for the number of passenger movement and average airfare for the next 10-12 years to come. Thus, the study recommends that stakeholders in the air transport sector should work towards improving the capacity and infrastructure to accommodate the growth of air travel demand for domestic air travel in Nigeria. Policy implications were made on how to regulate the sector by having a good pricing policy to control the air fare for the industry.

Performance and cost-effectiveness of air disc brakes and air drum brakes for truck semi-trailers in different road and speed conditions

2023-02-03T14:03:54+02:00

This study uses TruckSim^TM to model disc brakes and drum brakes on a fully loaded truck semi-trailer to study the performance of each brake type as downgrades and speeds vary. The brake performance is measured based on braking distance. A simplified economic comparison based on life cycle cost analysis to determine which road and vehicle conditions give rise to the cost-effectiveness of disc brakes is performed. The studies suggest that disc brakes shorten braking distances by 10-20%. They also suggest that the percentage reduction in braking distance as speed increases and downgrade gets steeper is approximately 12-19%. Evidence is provided that trucking companies operating their vehicles in steep terrain and at high speeds with disc brakes could benefit from 12-80% in long-term cost savings. Finally, at the societal level, by preventing crashes arising from rear-end collisions and runaway truck incidents, disc brakes save at least $649 million annually.

Friction heating and stress-strain state of ventilated disc brakes

2023-05-01T00:20:34+03:00

This paper describes the study of ventilated car disc brakes stress-strain conditions and friction under the pressure using the ANSYS environment. Such influencing factors are taken into account in the course of research as angular speed value, the pressure of the pads on the disk, the nature of the load application, convection, thermal expansion, etc. Computer modelling of the stress field and the transient thermal field in the area of contact between the pads and the disk is provided by the method of sequential thermostructural communication of the intermediate states of the brake model directly in the ANSYS Coupled Field Transient environment. Besides, the ANSYS calculations were also performed based on the primitive assembly model of two steel blocks (the discrepancy was less than 3%) to determine the identity of the theoretical knowledge about the heating of bodies as a result of the work to overcome frictional forces. Finally, a high level of calculation results convergence by analytical formulas and computer modelling was established. Since this approach justified itself, its principles were taken as a basis in the calculations of ventilated disc brakes of cars, which significantly facilitates their application, knowing the area of the active part of the disc (the rest of the boundary conditions are typical and correspond to the normal operating modes of the vehicle).

Factors of the capital structure of maritime sector companies for increasing business value - theoretical approach

2023-05-01T00:31:09+03:00

The global world and individual countries, which are influenced by the economic, financial crises, and pandemics that occur in one way or another, have a major impact on business and its performance. Declining consumption, disrupted settlements, limited or unavailable sources of finance, and other economic and financial reasons may cause business failures. Efficient and rational financial management is crucial for companies to survive and operate successfully under various conditions of the economic cycle, especially in times of crisis. It can be argued that, under modern conditions of market economy, making economically sound decisions about the structure of funding sources is one of the most important tasks for business companies, since the formation of a capital structure establishes the company's ability to maximise its return, manage risks effectively, and operate successfully in a competitive environment to meet the needs of a wide range of stakeholders. The maritime sector is strategically important and economically significant for any country. Companies in this sector make a significant socio-economic contribution across the entire state. When forming the capital structure in the maritime sector companies, certain exceptions are encountered since the operation of these companies requires a large amount of borrowed capital. Increasing the business value of maritime sector companies has a positive meaning nationally and internationally.

Attributes of modal choice in an industrial-based urban area: A case study on Savar Paurashava

2023-01-02T22:16:30+02:00

Road transportation does an excellent job of connecting Savar's inner and outer areas, but it might be difficult for commuters to decide which mode of transportation to employ because residents of Savar come from a wide range of socioeconomic backgrounds. It is necessary to do in-depth research on the characteristics of people in the study region who choose different modes of transportation to achieve the goal of selecting a certain mode for their travel. Where a person lives can have a significant impact on their typical patterns of travel behavior. People who live closer to the center of things have access to a wider variety of amenities than those who live further away, and as a consequence, their travel patterns are distinct from one another. The study's findings indicate that several factors, including income, age, gender, and vocational qualities and goals, influence a commuter's preferred method of transportation. When it comes to selecting a mode of transportation, the most predictable factors to take into account are trip time and cost. After conducting research, it was found that most excursions are made from this place to Motijheel, Tejgaon, and Savar Export Processing Zone for their services, businesses, and jobs, respectively.

Investigating snowplow-related injury severity along mountainous roadway in Wyoming

2023-04-08T12:26:07+03:00

Snow removal and deicing using snowplow trucks assist transportation agencies to enhance roadway safety and mobility. However, due to slower travel speeds during these operations, motorists often end up in crashes for poor visibility and disturbance of the snow. Despite the risk associated with snowplows, no previous study was found that exclusively investigate the factors associated with injury severity in snowplow-involved crashes. Therefore, this paper presents an extensive exploratory analysis and fills this knowledge gap by identifying the significant contributing factors affecting the occupant injury severity from the aspects of crashes with snowplow involvement. The study utilized eleven years (2010-2020) of historical snowplow-related crash data from Wyoming. Both the binary logit model and mixed binary logit model were developed to investigate the impacts of the various occupant, vehicle, crash, roadway, and environmental characteristics on the corresponding occupant injury severity. As one of the important findings from this research concludes that other vehicle drivers are more responsible than snowplow drivers contributing to more severe injuries in crashes involving snowplows. Recommendations suggested based on the modeling results are expected to help transportation agencies and policymakers take necessary actions in reducing snowplow-involved crashes by targeting appropriate strategies and proper resource allocation.