Transport Research Articles

Pengaruh Perceived Price Terhadap Willing To Buy Jasa Transportasi Indriver dengan Perceived Quality Sebagai Mediator

Transportation is a fundamental necessity for individuals across all social strata. An efficient transportation system ensures that people can easily traverse geographical distances, connect various communities, and facilitate interactions. The proliferation of online transportation companies has led to increased competition in the industry. As a result, these companies are increasingly focused on creating attractive promotions to influence users' decisions when choosing which application to use. To stand out in this crowded market, companies often introduce various promotions and discounts to attract potential customers. InDrive, a ride-hailing platform, distinguishes itself in the competitive market by offering unique and innovative features: price negotiation. The benefits of this feature include serving price-conscious consumers and offering flexibility to find a ride with a tariff that matches their budget. This innovative approach can generate cost savings for users while providing additional income opportunities for drivers. The research population consists of Telkom University students from the 2021-2023 cohorts, with 100 respondents selected through online questionnaires distributed via social media. The sampling method used was simple random sampling, and the data was analyzed using SPSS. The research findings indicate that the perception of price and the perception of quality on the InDrive application have a significant relationship, quality perception affects the willingness to buy InDrive transportation, price perception affects the willingness to buy InDrive transportation, and quality perception serves as a mediator between price perception and the willingness to buy..

Pengaruh Leverage dan Sales Growth Terhadap Financial Distress dengan Profitabilitas Sebagai Moderasi

The transportation sector in Indonesia is one of the important sectors supporting the national economy. This sector consists of a variety of companies and has great potential for development. This research is based on the problem of decreasing demand due to restrictions on mobility and economic activity due to the pandemic. Causing a decrease in revenue and profits for transportation companies which can increase the risk of financial distress. This research uses financial leverage ratio calculations with DER (Debt Equity Ratio) and Sales growth to determine the effect on financial distress calculated using ICR and the role of profitability with ROA (Return On Assets) as moderation. The method used in this research is descriptive methods with a quantitative approach. Research on the transportation sector listed on the BEI in 2022. The research population was 49 companies with a sample of 41 companies. The financial distress method used is to calculate the ICR ratio (Interest Coverage Ratio) which is symbolized by a dummy. Data analysis uses multiple linear analysis and Moderating Regression Analysis (MRA) with the SPSS 26 application. Based on the research and discussion that has been carried out, the research results can be concluded that leverage has an effect but is not significant on financial distress. Sales growth has an effect but is not significant on financial distress. Profitability is able to moderate the relationship between leverage and financial distress and sales growth with financial distress.

Generation of hydrogen fuel on board vehicles with internal combustion engines

This article discusses advances in the design of hydrogen fuel engines; the main characteristics of the hybrid engine are studied; prospects for further research are outlined; development and improvement of engine designs, research of processes in engines running on natural gas and hydrogen. Transport is one of the key elements of modern civilization. Its condition and development prospects largely depend on the ability to supply transport power plants with fuel. The depletion of liquid hydrocarbon fuel reserves and problems of environmental pollution may present humanity with a choice - either to reduce transport transportation or to find new ways to supply energy to transport. OBJECTIVE: To review the electrochemical technologies used for the production of hydrogen at gas stations and the operation of hybrid electric vehicle engines using fuel cell batteries. Conduct a comparative analysis of the production and use of energy by electrochemical and traditional methods in vehicles. METHODS are based on analysis of literature data and mathematical calculations. For a passenger electric vehicle, the amount of electricity that can be obtained in a fuel cell by processing 1 kg of hydrogen was calculated. It has been shown that the specific fuel consumption for a hydrogen electric vehicle averages 1 kg of hydrogen per 100 km. Hydrogen has the potential to be the sustainable fuel of the future, reducing global dependence on fossil fuel resources and reducing carbon emissions from the transportation industry.

Research on rigid-flexible coupling nonlinear dynamics of light commercial vehicle considering frame flexibility

Commercial vehicles play a vital role in the transportation industry. Generally, there will present a complex nonlinear dynamic behavior composed of periodic, quasi-periodic, and even chaotic vibration in vehicle vertical system under the continuous speed bump excitation. To explore the nonlinear dynamic behavior of vehicle system, a new rigid-flexible coupling nonlinear dynamic model for light commercial vehicle has been developed theoretically with considering the frame flexibility, suspension stiffness and damping nonlinearity, and rubber bushing nonlinearity. The dynamic model for frame and suspension have been developed with discrete element method and lumped mass method, respectively. Then, the flexible frame model has been verified through the mode shape and frequency calculated by finite element simulation. And the rigid-flexible coupling nonlinear dynamic model of a light commercial vehicle has been verified with Adams simulation and testing results. Furthermore, the influence of vehicle speed and the height of speed bump, suspension stiffness and damping, as well as cargo weight and distribution on vehicle system dynamics is analyzed with bifurcation diagram, time history, frequency, phase diagram and Poincare section. The results show the significant and complex effects on the nonlinear vibration of vehicle system, especially the nonlinear damping and the flexible frame.

Multi-objective model for electric vehicle charging station location selection problem for a sustainable transportation infrastructure

The transportation industry mostly depends on conventional vehicles, leading to significant adverse effects on the environment. The widespread usage of electric vehicles can be seen as a relief for this problem. However, the success of electric vehicles largely depends on the availability and proper deployment of charging station infrastructure. It is crucial for cities to strategically select suitable locations for charging stations with adequate capacity levels to promote sustainable and environmentally-friendly transportation options. Hence, in this study, a multi-objective model is proposed for the electric vehicle charging station location selection and capacity allocation problem. The model aims to maximize customer satisfaction, minimize total risk, and minimize costs as key objective functions. To manage the demand effectively, the region of interest is divided into grids. The proposed multi-objective model is applied to the European side of Istanbul and solved by using AUGMECON2 technique. Finally, computational analyses are presented based on scenarios including different demand values. These analyses provide valuable insights into the effectiveness of the proposed model and its implications for achieving sustainable transportation in Istanbul.

DECARBONIZING FREIGHT TRANSPORTATION IN BRAZIL: METHODOLOGIES, RESULTS AND PRACTICAL IMPLICATIONS

Objective: The objective of this technological article is to present a practical tool for calculating CO2 emissions based on fuel consumption applied in a small road freight transport company. Theoretical Framework: There are 4 methods available in the literature for calculating CO2 emissions produced during cargo transport, which stand out for their applicability: (1) GHG Procol; (2) MNT; (3) DEFRA; and (4) GLEC. The authors (Leonardi & Baumgartner, 2004; Lewis et al., 2016) have methodologies for calculating emissions from freight transport, which currently present significant variability in the approaches and databases recommended. The main methodologies in this area are based on two main foundations: (1) fuel-based methodologies; (2) activity-based methodologies. Method: The calculation methodology used is based on fuel consumption (bottom-up), which considered the characteristics of the target fleet, the number of vehicles and their technological phase, the actual intensity of fleet use in operation, and real fuel consumption. Results and Discussion: From this initial information, it was possible to obtain the volume of CO2 emissions specific to the fleet, considering vehicles using regular diesel and biodiesel (S10). The results indicated a fleet CO2 emission of 1,643 tons per year with the use of biodiesel (S10), representing a 10.5% reduction compared to the total CO2 emission from regular diesel. Research Implications: The practical and theoretical implications of this research are discussed, providing insights into how the results can be applied or influence practices in the field of [insert field of study]. These implications could encompass [list impacted areas or sectors]. Originality/Value: This technological article contributes to the presentation of a review of CO2 emission calculation models available in the literature and the selection of a methodology for easy application for small and medium-sized road freight transport companies.

Research on the Efficiency of Major Airports in China’s Six Major Airport Cluster: Based on Common Frontier Super-Efficiency DEA and Malmquist Method

Airport clusters are of great significance to the sustainable development of the civil aviation transportation industry. The study utilises common frontier and super-efficiency DEA methods to assess the efficiency of China’s six major airport groups. It then employs the Malmquist index method to analyse changes in airport productivity. The results highlight regional disparities in airport efficiency. The East China Airport Group and the Southwest Airport Group consistently demonstrate excellent efficiency values, while the North China Airport Group and the Northeast Airport Group have significant room for improvement. Most airports within the groups operate at low and ineffective levels, with efficiency initially increasing and then decreasing. Moreover, the technology gap ratio (TGR) for each airport group somewhat shows a downward trend. The Malmquist index indicates that the overall factor productivity of each airport has generally remained stable, with efficiency growth primarily dependent on scale efficiency. On average, technical efficiency has increased by 1.5%. However, in terms of technological changes, most airports have experienced technological regression, indicating insufficient focus on technological improvement. Therefore, it is crucial to prioritise technological innovation and enhance management efficiency to achieve efficiency improvements in airport clusters. It is necessary to formulate strategies accurately based on the specific conditions of different regions, promote coordinated development, foster regional exchanges and cooperation, address regional disparities, ensure sustainable development of China’s airport clusters, and establish a world-class airport cluster.

Breakup dynamics in a pressure-swirl injector for urea-water solution applications: A computational study

The co-optimization of in-cylinder combustion and after-treatment technology has become a major aspect in engine design and development, with the goal of meeting the increasingly restrictive emission regulations in the transportation industry. Selective Catalytic Reduction is a robust technology to control the emission of NOx, and the injection of urea in water solution is the exhaust tailpipe is a key aspect of its operation. The proposed work uses high-fidelity Computational Fluid Dynamics to characterize the atomization dynamics of the liquid jet in relevant cross-flow conditions. The study focuses on a commercial low-pressure (9 bar) pressure-swirl injector which is characterized in its internal geometry through high-resolution X-ray micro-computational tomography. The internal two-phase flow has been modeled according to the volume-of-fluid approach in a large eddy simulation framework and validated against near-nozzle X-ray radiography measurement. Moreover, characterizing the breakup dynamics for the swirling hollow cone formation, and assessing the influence of the cross-flow in the breakup dynamics was completed. The results have been reported proposing Re-Oh maps and probability density functions of the spray kinematics. Higher cross-flow momentum generates an increase in the jet intact length and a reduction of the liquid droplet diameters. The axial momentum of the jet is affected by the cross-flow already in the near-nozzle region, determining a relevant deviation of the spray velocities. This work aims to inform the initialization of Eulerian-Lagrangian spray models through the assignment of droplet kinematics and static one-way coupling between volume-of-fluid results and Lagrangian spray parcels, to be used for system-size domain simulations.

Identifying possible ways for adapting an open wagon for transporting containers

The object of this study is the processes of perception and redistribution of loads in the supporting structure of a open wagon loaded with containers, taking into account the new scheme of their fastening. For safe transportation of containers in an open wagon, it is suggested to use a removable module. This module works according to the principle of an intermediate adapter between the container and the open wagon body. Fastening of the module itself in the open wagon is carried out through the fitting stops, which are placed on the floor of the open wagon. Mathematical modeling was carried out to determine the longitudinal dynamic load acting on the container fixed according to the new scheme in the open wagon. To this end, a mathematical model was built that characterizes the longitudinal movements of the "open wagon - removable module - container" system. Determination of the accelerations that act on the supporting structure of the open wagon loaded with containers was also carried out by means of computer simulation. Verification of the formed model of the dynamic load of the open wagon was carried out according to the F-criterion. Also, as part of the study, a modal analysis of the load-bearing structure of a open wagon loaded with containers was carried out, which made it possible to assess its traffic safety. A feature of the results obtained as part of the research is that the proposed design of the removable module could be used not only for fastening containers but also for transportation of other types of cargo. The field of practical application of the results is railroad transport, including other transportation industries. The conditions for the practical use of the results are a symmetrical scheme of loading the body of a open wagon with containers. The results of this study will contribute to increasing the efficiency of container transportation and the profitability of railroad transport

Role of energy value chain in carbon neutrality: A review

Value chain analysis is an important tool for optimizing operations and decision-making in enterprises. As the concept of sustainable development gains recognition worldwide, research on value chains is increasingly focused on sustainability. Traditionally, energy management and value management have operated in parallel with limited intersections. However, after the 2015 Paris Agreement set the goal of achieving net-zero emissions, carbon management has become integral to national strategies, necessitating a re-evaluation of traditional value chains. In this paper, the “energy value chain” is introduced, a novel concept that integrates energy consumption with value creation and carbon emissions, emphasizing the coupling relationships among “energy flow”, “value flow”, and “carbon flow.” From a review of current value chains in the power, steel, petroleum, and transportation industries, the specific energy value chain for each industry is defined and its rationale and effectiveness are discussed. This integrated analytical method provides a strategic tool for industries or enterprises to optimize energy consumption, reduce carbon emissions, and enhance competitive advantage.

Potential for material valorization of composites (glass fiber in polyester resin) in concrete: performance evaluation on mortar

IntroductionGlass fibers with polyester resin structural composites are highly sought after in many sectors such as transportation industries, thanks to their low density and fairly good mechanical properties. However, their end-of-life management is not yet satisfactory. Composites mostly end in energy recovery in the best-case scenario or, worse, in landfills. Transformation into shreds and powders for reuse as a new source of raw material for the construction sector (concrete) is an economically and environmentally attractive recovery solution. The present study investigates the development of a concrete filled with glass/polyester composite shreds.MethodsTo this end, rheological (cone spread) and physico-mechanical (density and mechanical strength in flexion and compression) characterization tests were carried out. Several mix designs were tested in order to understand the impact of introducing composite shreds as a substitute for sand. Composite shreds were introduced in the following ratios by volume: 0, 1, 1.5, 2, 2.5, 3, and 7% with water and cement ratio equal to 0.5, 0.6, and 0.7.Results and discussionThe results obtained indicate that workability decreases with the substitution of sand by shreds. For a substitution of sand by shreds of 2%, it is relatively small, and the pouring of the mortar is still feasible. The decrease can be attributed to the water absorption of the composite shreds. Concerning mechanical results, for formulations with a substitution percentage of composite shreds lower than 3%, the mechanical strength (both compression test and flexure test) is slightly higher than that of the reference sample. The increase in compressive strength that can be observed is at its maximum, equal to 10%, compared to that of the reference sample. These results are in line with density results, which are also slightly higher than that of the reference sample. This effect can be attributed to water absorption of composite shreds and the filling effect of the powders. For a percentage of substitution equal to 7%, the mechanical strength is lower than that of the reference sample (30% decrease), with a compressive strength equal to 33 MPa (47 MPa for the reference sample). For this percentage of substitution equal to 7%, a decrease in density is also observed (6% decrease) and can be explained by the porosity created by the incorporation of the composite shreds into the mortar.

Environmental Education in the Business Context: Practices and Challenges in the Transportation Sector for the Formation of a Socio-Environmental Culture

Objective: The objective of this study is to investigate Environmental Education in the business context, with a focus on the transport sector, in order to reflect on the teaching practices that are developed in all areas, with the aim of presenting environmental practices that can promote the formation of an individual committed to the socio-environmental reality and to life. Theoretical Framework: Environmental Education can be characterized as an educational process based on social values, knowledge, skills, attitudes and competencies aimed at conservation and care for the environment. This definition highlights the need for its operationalization at all levels and sectors of society in a cultural transformation project, which intends the necessary contribution of Formal Education. Based on the proposal, the study supports the need for the rapid implementation of environmental education within urban transport companies, so that in the medium to long term it is possible to observe a strengthened sustainable dynamic in environmental education for this sector. Method: The methodology adopted for this research involves dividing the study into two parts, where the first was based on a systematic review of the scientific literature and the second part, due to the scarcity of significant data on the subject identified in the initial phase, was configured as a professional proposal for implementing environmental education within the urban public transport sector. Results and Discussion: The results obtained revealed important implications for the promotion of sustainability in the transportation sector through Environmental Education by proposing a practical approach that combines educational and operational strategies, highlighting the need for companies to integrate socio-environmental responsibility actions into their daily practices, increasing environmental awareness among employees, but also fostering cultural transformation in organizations, generating a broader impact. In addition, the research can serve as a model for other industrial sectors, offering a replicable framework for implementing sustainability programs in a systematic way and adapted to the needs of each organizational context. By combining a rigorous analysis of the scientific literature with the proposal of a practical product for the implementation of Environmental Education in transportation companies, focusing on the specific needs of the transportation sector, it is possible to bring solutions that are applicable and adaptable to the reality of organizations, which increases its relevance both in the academic field and in the market. The study not only fills gaps identified in the literature, but also contributes with an action model that can be directly implemented, bringing benefits to companies, employees and society in general. Research Implications: The practical and theoretical implications of this research are discussed, providing insights into how the results can be applied or influence practices in the urban transport field. These implications may include the promotion of sustainability in the transport sector through Environmental Education by proposing a practical approach that combines educational and operational strategies, highlighting the need for companies to integrate socio-environmental responsibility actions into their daily practices, increasing environmental awareness among employees, but also fostering cultural transformation in organizations, generating a broader impact. Originality/Value: This study contributes to the literature by also serving as a model for other industrial sectors, offering a replicable framework for implementing sustainability programs in a systematic manner and adapted to the needs of each organizational context. In this context, the work emphasizes the relevance of intersectoral partnerships, which can drive public policies and collaborative actions between the private and public sectors to promote a more sustainable transition.

Analysis of Optimal Water Levels in the Great Lakes Based on A Comprehensive Satisfaction Function

The purpose of this paper is to analyze the optimal water levels in the Great Lakes to meet the needs of multiple stakeholders and thus achieve sustainable development in the region. The Weight-Function-Synthesis-Optimization (WFSO) model was used in this study. By classifying the water level needs of different interest groups, their respective satisfaction functions are established, and the overall satisfaction function is formed by weighting. In addition, the quadratic polynomial function is used to fit the optimal monthly water level time series of Lake Ontario, and the fitting effect is good, fully reflecting the periodic and seasonal changes in the water level of Lake Ontario. By considering the priorities of various stakeholders, this paper defines an overall satisfaction metric, "allsa," and identifies a time series of monthly optimal water levels for Lake Ontario and beyond. The ideal water level was determined to be 74.9 meters. The study results suggest that maintaining this water level can maximize the satisfaction of ecosystems, transportation, real estate, terminals, and hydropower companies, and promote sustainable development of the region.

Islamic life and death in Australia, after 1890: The archaeology of cameleer burials

Among the best-preserved, prominent, and most diagnostic archaeological artefacts of the camel transport industry from the period after ∼1890 in Australia are the graves of Muslim cameleers that can be found across the continent, from a single grave at the most isolated site to cemeteries in capital cities. They tell a story—directly from the cameleers—that usually cannot be read from other evidence. These graves vary from the simplest tumuli in remote areas that conform with the strictest Islamic ideals to complex graves with a superstructure, headstone and a detailed epitaph. English may be used in epitaphs with or without Arabic or Dari, and less commonly we see Arabic or Dari with no English. This makes it clear that Muslim epitaphs were not solely addressing other Muslims. In many cases, the name, date and origin of the interred individual remains unknown, and this prevents more detailed interpretation. In other cases, graves with greater complexity may include passages from the Quran, and there are even some epitaphs that give great personal details of Muslim life in Australia. Such detail includes divisions between tribes and Islamic sects. Major deviations from correct Islamic grave orientation in two cemeteries cannot be convincingly explained, but these suggest another case of diversity in the tribal and sect affiliation of these individuals. Burials of these Muslims restored in the late twentieth century are no longer solely religious monuments but are also socially motivated in a more diverse and integrated Australia. There are several indicators by which the graves of Muslims can be identified, but they may also overlap with Christian graves in other elements of style. These indicators tie burial practices to Islam in Asia. Finally, orientation relative to the qiblah is not invariably diagnostic.

Development of a Comprehensive Safety Evaluation Mechanism for the Highway Bus Industry

A suitable mechanism for evaluating the safety of the highway bus industry is crucial for ensuring public transportation safety in a country. In this study, we have combined indices from the Compliance Safety Accountability (CSA) program of the Federal Motor Carrier Safety Administration (FMCSA) in the US, the safety evaluation of renting buses in Japan, and some existing safety evaluation methods in Taiwan to develop a new safety evaluation mechanism for the highway bus industry. This paper introduces a two-stage decision making approach that includes the use of fuzzy analytic hierarchy process (Fuzzy AHP) and machine learning techniques such as decision trees, support vector machines, and random forests to develop this mechanism. The data used in this research were collected from the internet and directly from highway bus transportation companies. We calculated the safety performance of each company and assigned them different safety ranks. Compared with the causes of accidents in Taiwan, the results of this study showed that work hours, driver fitness, and administrative penalties are the three most important sub-attributes that affect the safety rank of the company.

Factors Related to mHealth App Use Among Japanese Workers: Cross-Sectional Survey.

Health care providers can make health guidance more effective by using mobile health technologies such as health apps. Although health care providers need to know who uses health apps, existing studies have yielded inconsistent results. The aim of the study was (1) to clarify the prevalence and patterns of health app use to improve health behaviors for preventing lifestyle-related diseases among Japanese workers and (2) to identify the associations among demographic characteristics, health behavior, and internet use and health app use by gender. Data were collected from a cross-sectional internet survey in 2023. In total, 2200 participants were included, with an even distribution of men and women in each age group aged 20 to 60 years. The participants were workers with smartphones and reported their gender, age, residence area, marital status, education, employment status, occupation, work pattern, diseases under treatment, health checkups, health guidance, health behaviors, internet use duration, and number of devices used. We asked about current and previous health app use for 1 month. A multivariate logistic regression analysis was conducted by gender. Of the participants, 472 (21.5%) and 189 (8.6%) were current and previous health app users, respectively. Most current and previous health app users used features that record and track their physical activity and other health behaviors. Health app users-both men and women-were more likely to have health checkups (odds ratio [OR] 1.53, 95% CI 1.12-2.11 and OR 1.51, 95% CI 1.10-2.07, respectively), receive health guidance (OR 2.01, 95% CI 1.47-2.74 and OR 1.86, 95% CI 1.32-2.62, respectively), engage in regular physical activity (OR 2.57, 95% CI 1.91-3.47 and OR 1.94, 95% CI 1.41-2.67, respectively), use the internet for 120-179 minutes per day (OR 1.76, 95% CI 1.13-2.75 and OR 1.70, 95% CI 1.12-2.57, respectively), and were less likely to be older (50-59 years: OR 0.54, 95% CI 0.33-0.88 and OR 0.40, 95% CI 0.25-0.6, respectively, and 60-69 years: OR 0.37, 95% CI 0.22-0.62 and OR 0.47, 95% CI 0.28-0.77, respectively). According to gender, male health app users were more likely to be married (OR 1.69, 95% CI 1.23-2.33) and less likely to work in the security, agriculture, forestry, fishing, manufacturing, or transportation industries (OR 0.62, 95% CI 0.41-0.95). Female health app users were more likely to have a university education or higher (OR 1.55, 95% CI 1.061-2.26), maintain an appropriate body weight (OR 1.52, 95% CI 1.10-2.11), and use 3 or more devices (OR 2.13, 95% CI 1.41-3.23). Physical activity and health guidance are strong predictors of app use. Health care providers should assess the target populations' preferences for app use based on their characteristics, support their app use, and enhance the effectiveness of health guidance.

Experimental performance evaluation of direct cooling of hot stamping dies using fractal cooling channels

Hot stamping is a promising technology to reduce carbon dioxide emissions in the transportation industry by decreasing the weight of components with appropriate strength. However, the low cooling performance of conventional indirect cooling channels degrades the product quality and production rate during hot stamping. This study proposes a novel direct cooling system for hot stamping dies with fractal cooling channels (FCCs). Based on experiments, the cooling performance of the FCC was analyzed at various press holding times, mass flow rates, and cycle numbers. In the FCC, the average blank temperature at a water mass flow rate of 50 kg h−1 was 22 % lower than that at a zero-mass flow rate. At a mass flow rate of 50 kg h−1, the average blank temperature in the FCC increased with the cycle number and converged to 186 °C in the seventh cycle. Additionally, the standard deviation of the temperature distribution in the FCC was on average 39 % lower than that in the straight cooling channel (SCC). Finally, the daily production rate in the FCC was 34 % higher than that in the SCC.

Hardware-in-the-Loop Implementation of an Optimized Energy Management Strategy for Range-Extended Electric Trucks

The reliance of the commercial transportation industry on fossil fuels has long contributed to pollutant and greenhouse gas emissions. Since full electrification of medium- and heavy-duty vehicles faces limitations due to the large battery capacity required for extended driving ranges, this study explores a Range-Extended Electric Vehicle (REEV) for medium-duty Class 6 pick-up and delivery trucks. This hybrid architecture combines an electric powertrain with an internal combustion engine range-extender. Maximizing the efficiency of REEVs requires an Energy Management Strategy (EMS) to optimally split the power between the two power sources. In this work, a hierarchical EMS is developed through model-based design and validated via Hardware-In-The-Loop (HIL) simulations. The proposed EMS demonstrated a 7% reduction in fuel consumption compared to a baseline control strategy, while maintaining emissions and engine start frequency comparable to a benchmark globally optimal EMS obtained with dynamic programming. Furthermore, HIL results confirmed the strategy’s real-time implementation feasibility, highlighting the practical viability of the controller. This research underscores the potential of REEVs in significantly reducing emissions and fuel consumption, as well as providing a sustainable alternative for medium-duty truck applications.

Optimization of power performance and combustion stability of ultra-lean combustion in hydrogen fuel engines through combined turbulent jet ignition and variable valve timing

Although pure hydrogen engines can achieve zero carbon and extremely low NOx emissions under ultra-lean combustion conditions, there are limitations with combustion stability and power performance. This paper combines turbulent jet ignition (TJI) and variable valve timing (VVT) technology, which not only improves the power output of pure hydrogen engines under ultra-lean combustion conditions but also ensures the engine’s stable operation. Therefore, this research reveals the working characteristics of TJI engines under lean conditions through numerical methods and explores the optimization characteristics of VVT on engine power performance and stability through experiments. The results indicate that TJI utilizes strong turbulence and multiple-point ignition to improve the efficiency of the mixture and combustion speed, ensuring reliable ignition capability under ultra-lean operating and achieving a stable and effective combustion process. According to the experimental results, the combination of TJI with VVT technology can ensure engine cyclic-variability of less than 1.5 % and the maximum values of Brake mean effective pressure (BMEP) and Brake thermal efficiency (BTE) are 4.5 bar and 41.6 %, respectively. This innovative technology combination not only enables the efficient and eco-friendly development of the transportation industry but also holds significant importance for promoting carbon-free fuels and environmental protection in the future.

Gaidai multimodal risk evaluation methodology based on cargo vessel onboard measurements, given structural damage accumulation

Intercontinental transportation relies heavily on medium-to-large cargo vessels, constituting an essential component of the global trade. Thus, it is of paramount importance for trading companies, engineers, designers to advance innovative, economically viable logistical and structural schemes, that are safe and reliable. Full-scale onboard recorded data, when available, serves as valuable diagnostic tool that is hard to overestimate. An operating medium-size cargo ship TEU2800 had been selected for the current investigation. TEU2800 hull dynamics is by excessive deck panel strains, occurring during ship's intercontinental sailings through potentially adverse weather conditions. Inherent risks of damaging vessel hull and losing containers, caused by excessive motions/loads, being one of the primary concerns for the cargo transportation industry. Primary novelty of this investigation is twofold: for the first, a unique onboard measured representative dataset had been analyzed; for the second, novel multimodal reliability methodology had been employed to analyzed raw measured onboard data.Presented study advocates the state-of-the-art Gaidai multimodal spatiotemporal risks assessment methodology, enabling conservative structural hazard/damage/failure risk forecasting for nonstationary, nonlinear, multimodal cargo vessel hull dynamics, under accumulated fatigue damage. Note that the advocated novel multimodal risks evaluation methodology being of generic nature and may be straightforwardly applied to a wide range of contemporary complex naval, offshore, marine systems, hence not being limited to cargo vessels only.