Transport System Research Articles

Ultra-stable transportable ultraviolet clock laser using cancellation between photo-thermal and photo-birefringence noise

Optical clocks require an ultra-stable laser to probe and precisely measure the frequency of the narrow-linewidth clock transition. We introduce a portable ultraviolet (UV) laser system for use in an aluminum quantum logic clock, demonstrating a fractional frequency instability of approximately mod σy = 2 × 10−16. The system is based on an ultra-stable cavity with crystalline AlGaAs/GaAs mirror coatings, with a frequency quadrupling system employing two single-pass second-harmonic generation (SHG) stages. Its acceleration sensitivity, measured in all three axes, does not exceed 4(2) × 10−12/(ms−2) and is among the lowest recorded for transportable systems to date. Additionally, partial cancellation between photo-thermal noise and photo-birefringence noise is used to effectively mitigate noise induced by intra-cavity optical power fluctuation at lower Fourier frequencies.

Adapting the ITF's Transport Policy with a Focus on the EU's Strategy of Sustainable Mobility

Urban regions worldwide face increasing challenges in mobility planning due to transformative developments such as climate change, energy crises, migration, digitalisation, and the rise of artificial intelligence. In Europe, frameworks like the European Union's Sustainable and Smart Mobility Strategy and the International Transport Forum's (ITF) policy measures aim to create sustainable, multimodal, and efficient urban transport systems. This paper explores how these frameworks can be integrated to enhance urban mobility governance, focusing on the Brussels-Capital Region’s Good Move plan. The plan emphasises shared mobility, digitalised multimodal systems like mobility as a Service (MaaS), and a regulatory framework that balances innovation with public oversight. Through a "learning by doing" approach, this study highlights the interplay between public and private actors, effective data governance, and market regulation to establish a viable MaaS ecosystem. Key findings underline the potential of MaaS to reduce urban emissions, improve accessibility, and promote sustainable travel while addressing regulatory challenges such as data-sharing, competition safeguards, and equitable mobility subsidies. The paper concludes with actionable recommendations to optimise MaaS integration and support urban regions in achieving resilient, livable cities through sustainable mobility solutions.

Intermodal practices between land transport and the hub of Lomé airport in Togo

All air travellers in Togo pass through Gnassingbé Eyadéma International Airport (AIGE: Aéroport International Gnassingbé Eyadema) of Lomé. To get in or out of the airport, they must use other means of land transport as part of an intermodal approach. The urban transport system in Lomé is disjointed, with no interconnection between the land transport hubs and the airport hub, making it extremely difficult for users to get to and from AIGE. It is true that there is a public transport service called SOTRAL, but it does not serve the airport, while the use of artisanal transports to access the airport is prohibited or very restricted. The aim of this study is to analyse intermodal practices between land and air transport in Great Lomé District. The methodological approach used is based on surveys of passengers at bus stations and AIGE, interviews with transport stakeholders, counts of feeder and distribution modes, and observation of practices in the field. The study shows that in the absence of a specific transport service to serve the main multimodal hubs such as the airport, travelers are bound to use their own means of transport or hire very expensive artisanal transports or private vehicles to get to the airport. To leave the airport, travelers make more use of the airport’s VIP private taxis (32%), which are very expensive on arrival. Those who do not want to hire the airport’s expensive private taxis are forced to walk 300 m with their parcels to pick up a city taxi at the side of the road.

Intelligent Traffic Light Control System and Application

In recent years, with the surge in the number of vehicles, traffic congestion has become an increasingly severe global issue. So Intelligent Traffic Signal Control Systems have emerged as a critical component of transport systems to address this challenge by optimizing traffic flow, reducing delays, and enhancing road safety. The intelligent system depends on several advanced technologies, such as IoT devices, big data analytics, and artificial intelligence algorithms. Also, the system can dynamically adjust traffic signals based on real-time road conditions via technologies such as Vehicle-to-Infrastructure (V2I), Vehicle-to-Vehicle (V2V), and Vehicle-to-Everything (V2X) communication, which successfully improves traffic flow during peak hours, and minimizes congestion. The review will also mention successful case studies in cities such as Beijing, where smart systems have significantly improved traffic efficiency. The last part of review will focus on future developments about scalability, cost-effectiveness, and data security to ensure the continued success of these systems in modern urban environments.

Agricultural Optimization through Radioactive Tracer Technology: Applications, Challenges, and Future Directions

Radioactive tracer technology has emerged as a groundbreaking tool for advancing agricultural optimization, particularly in the study of physiological and biochemical processes in fruit crops. By utilizing isotopic tracers, researchers can achieve unparalleled precision in tracing nutrient pathways, imaging biological processes, and diagnosing molecular interactions. This review explores the diverse applications of this technology, including the optimization of nutrient uptake, the analysis of water transport systems, the enhancement of photosynthetic efficiency, and the management of pest-related challenges. Additionally, the study addresses the logistical, safety, and economic considerations surrounding the use of radioactive tracers in agricultural research. The integration of machine learning and advanced imaging techniques is highlighted as a pivotal development, amplifying the scope and effectiveness of radioactive tracer applications. Together, these innovations promise to revolutionize the understanding and management of crop systems, paving the way for sustainable and efficient agricultural practices.

An investigation into the impact of diapir structures on formation pressure systems: a case study of the Yinggehai Basin, China

Under the influence of diapir structure, the formation pressure system is complicated. The characteristics of high temperature and high pressure are obvious, the prediction is difficult, and complex accidents such as well kick and leakage are frequent, which seriously restrict the efficient development of oil and gas resources. Therefore, taking Yinggehai Basin in China as an example, combined with the evolution characteristics of diapir structure, the influence of diapir structure on abnormal high-pressure, wellhole collapse and fracture is analyzed. Three pressure calculation methods are selected, and the distribution rules of pressures and safety density window are analyzed, too. The results show that the diapir structure and its associated fault not only constitute the fluid transport system, but also make the deep overpressure transfer upward and accumulate into high pressure in the shallow formation, and the development of the associated fault destroy the integrity of the formation rock and reduce the strength of the rock. The upwelling of hot fluid changes the local geothermal conditions, reduces the hydrocarbon generation threshold of shallow source rocks, promotes the evolution of clay minerals, causes hydrothermal expansion, and enhances the shallow high pressure. In high-temperature environment, the cooling effect of drilling fluid will produce heating stress, change the stress distribution around the wellhole, and increase the risk of wellbore instability. Additionally, under the influence of diapir structures, the pore pressure in deep formations increases, while the fracture pressure decreases, resulting in a significantly narrowed safe density window. The safety density window width generally presents a half-spindle shape, and with the increase of depth, the window width increases first and then decreases.

The dual impact of tire wear microplastics on the growth and ecological interactions of duckweed Lemna minor.

Tire wear microplastics (TWMs) are continuously generated during driving and are subsequently released into the environment, where they pose potential risks to aquatic organisms. In this study, the effects of untreated, hydrated, and environmentally aged TWMs on the growth, root development, photosynthesis, electron transport system (ETS) activity, and energy-rich molecules of duckweed Lemna minor were investigated. The results indicated that untreated and aged TWMs have the most pronounced negative effects on Lemna minor, as evidenced by reduced growth and impaired root development. In contrast, the effects of hydrated TWMs were less. The negative effects associated with untreated and hydrated TWMs are primarily attributed to the abrasive nature of these particles, which physically damage the plant tissue. On the other hand, environmentally aged TWMs showed a different mode of action as they serve as transport vectors for algae. Once introduced into a new environment via aged TWMs, these algae competed with Lemna minor for available nutrients and space, further impairing the growth, root length, photosynthetic efficiency, and carbohydrate content of Lemna minor. This study revealed the dual threat posed by TWMs: direct physical damage from newly released particles and indirect ecological disruption from aged particles that facilitate the spread of algae.

Genetic Underpinnings of Oligoasthenoteratozoospermia.

Oligoasthenoteratozoospermia (OAT) is a frequent but severe type of male infertility. As one of the most multifaceted male infertility resulting from sperm problems, its genetic etiology remains unknown in most cases. In this review, we systematically sort out the latest literature on clinical reports and animal models leading to OAT, summarise the expression profiles of causative genes for OAT, and highlight the important role of the protein transport system during spermiogenesis, spermatid cell-specific genes, Golgi and acrosome-related genes, manchette-related genes, HTCA-related genes, and axoneme-related genes in OAT development. These causative genes would be instrumental in genetic etiological screening, genetic counseling, and pre-implantation genetic testing of patients with clinical OAT.

The Mediating Effect of Service Quality on the Relationship between Ride-Hailing Driver Characteristics and Customer Satisfaction

Purpose: This study explored the relationship between the ride-hailing transport system, service quality, customer satisfaction, and driver characteristics among university and college students in major cities in Ghana. Design/Methodology/Approach: Using a quantitative approach, data were collected from a sample of 436 ride-hailing users through the simple random sampling technique. A cross-sectional research design was employed for data gathering, and Partial Least Square Structural Equation Modeling (SEM) version 4.0 was utilised for data analysis. Findings: The findings indicated that the ride-hailing transport system significantly influenced service quality and overall customer satisfaction. Additionally, driver characteristics such as skills, punctuality, and age impacted customer satisfaction. The study also established a positive relationship between service quality and customer satisfaction. Research Limitation: Research within specific geographical areas or demographics restricts the findings' applicability to other cultural or economic contexts. Practical Implications: The results highlight the necessity for transportation network companies (TNCs) to improve driver training and service quality to boost customer satisfaction, foster loyalty, and enhance business performance. Social Implications: The study's insights on the mediating effect of service quality will guide policymakers in identifying key factors influencing consumer satisfaction in the ride-hailing industry. By understanding these dynamics, policymakers can develop regulations that enhance service standards, benefiting drivers and passengers through improved operational frameworks. Originality/ Value: This research contributes to the existing literature on ride-hailing transport systems by emphasising the critical roles of service quality and driver characteristics in enhancing customer satisfaction.

УЛУЧШЕНИЕ УПРАВЛЕНИЯ ИНФРАСТРУКТУРОЙ ВОЗДУШНОГО ТРАНСПОРТА

The organizers of the ground infrastructure of civil aviation and its current state are comprehensively analyzed and assessed, unresolved problems are identified. The purpose of the article is to develop the transport system as a whole and air transport, which is an important area, which is a prerequisite for the implementation of the innovative model of economic growth in Azerbaijan, as well as an important factor in improving the well-being of the population and the economy as a whole. The object of the research is the service infrastructure that uses the existing advantages of increasing the competitiveness of the national economy (fast delivery of passengers and cargo, no road construction, the ability to get to any point, etc.). The research method is modern methods and technologies of scientific knowledge, methods and techniques for conducting scientific research, tools for system, complex, economic analysis, principles of transport system management, which allow revising existing approaches in modern economic conditions. The hypothesis of the research was the assumption of the possibility of determining the logic of cognition of the process of managing transport potential in modern conditions. The statement of basic materials. It is proven that air transport is used in the study purposefully. It is confirmed that the importance of air transport infrastructure in the implementation of the innovative model of economic growth of Azerbaijan is very important given the preservation of the integrity and security of the country's territory in order to improve the quality of life of the population. In conclusion, proposals were made in the direction of improving the management of air transport infrastructure. The originality and practical significance of the study is confirmed by the stated priority of air transport development. Conclusions and prospects for further research consist in the implementation of a radical increase in competitiveness compared to other modes of transport, and for this reason, improving the management of air transport infrastructure has now become very relevant. Therefore, the formation of an effective development of special programs for the management of air transport infrastructure is a priority of the national economy. Further research will be aimed at developing special programs for the management of air transport infrastructure, based on the scope of their regional location

Assessment of the Impact of the Transport and Logistics System on Resource Efficiency, Key Regional Economic Indicators and Economic Sustainability

The objective of the study is to determine the degree of dependence between the regional transport and logistics system and the main regional economic indicators and their impact on resource-saving and the level of economic sustainability.The research methods are based on the use of a comparative analysis of approaches used to determine the characteristics of transport and logistics systems, retrospective, correlation and regression, morphological, abstract logical, theoretical and empirical, and structural analysis.The study has resulted in the analysis of approaches to defining and assessing transport and logistics system from the position of the spatial location of transport and logistics infrastructure facilities in the context of their impact on spatial organisation of productive forces; a retrospective, comparative and correlation and regression analysis of indicators characterising the regional transport and logistics system, economic indicators of GRP and retail turnover; evaluation of the analytical dependence of the region’s economic indicators on the state of the regional transport and logistics system; rationale of the dependence of the level of economic sustainability and resource-saving on the development of the transport and logistics infrastructure.The results of the study may be used to determine the level of influence of the transport and logistics system on regional economic indicators of various industries, which are indicators of their economic sustainability within the framework of the adopted regional strategy for planning the spatial distribution of transport and logistics infrastructure facilities.

Cefiderocol Resistance Conferred by Plasmid-Located Ferric Citrate Transport System in KPC-Producing Klebsiella pneumoniae.

Cefiderocol (FDC), a siderophore-cephalosporin conjugate, is the newest option for treating infection with carbapenem-resistant gram-negative bacteria. We identified a novel mechanism contributing to decreased FDC susceptibility in Klebsiella pneumoniae clinical isolates. The mechanism involves 2 coresident plasmids: pKpQIL, carrying variants of blaKPC carbapenemase gene, and pKPN, carrying the ferric citrate transport (FEC) system. We observed increasing FDC MICs in an Escherichia coli model system carrying different natural pKpQIL plasmids, encoding different K. pneumoniae carbapenemase (KPC) variants, in combination with a conjugative low copy number vector carrying the fec gene cluster from pKPN. We observed transcriptional repression of fiu, cirA, fepA, and fhuA siderophore receptor genes in blaKPC-fec-E. coli cells treated with ferric citrate. Screening of 27,793 K. pneumoniae whole-genome sequences revealed that the fec cluster occurs frequently in some globally distributed different KPC-producing K. pneumoniae clones (sequence types 258, 14, 45, and 512), contributing to reduced FDC susceptibility.

Decarbonizing the Transport of Microalgae-based Products —The Role of E-mobility

Background: The decarbonization of road transport is a precondition for achieving carbon neutrality. Battery-electric vehicle technology, driven by several patents, can make this a reality. In this bias, the objective of the article is to shed light on the ongoing debate about the potentially important role of the adoption of electric vehicles in the transport of microalgae-based products to help them advance to a cleaner life cycle. Methods: Five routes, including unimodal and multimodal conditions, were defined to assess the carbon emissions of the transport system and, more specifically, of road transport. The headquarters of market-leading microalgae manufacturers were selected as the origin of the routes and, as the destination, regions that sustain them. Results: The results reveal the supremacy of road transport of microalgae-based products using electric vehicles powered by nuclear, hydroelectric, and wind, followed by biomass and photovoltaic energy. They also show that the positive impact of wind, water, and photovoltaic energy on the climate, added to the lower battery charging costs and the greater opportunity to generate revenue from the sale of carbon credits, make their trade-offs. Conclusion: The exquisite results of this study convey key messages to decision-makers and stakeholders about the role of electromobility in building a zero-carbon delivery route.

Inclusion persons with disabilities to a public transport system: An integrative decision-aiding approach

Inclusion persons with disabilities to a public transport system: An integrative decision-aiding approach

Policy options for low-carbon sustainable transport systems in Kathmandu Valley, Nepal: A survey-based study

Policy options for low-carbon sustainable transport systems in Kathmandu Valley, Nepal: A survey-based study

Universal Accessibility Index: A Pedestrian Centered Accessibility to Inclusive Transport System

Universal Accessibility Index: A Pedestrian Centered Accessibility to Inclusive Transport System

Ionic liquid-containing polymer including membrane for the removal of cobalt: Synthesis, adsorption, transport, and modeling studies

This work describes synthesis of polymer inclusion membranes (PIMs), which is prepared by using varying ratios of polyvinylidene fluoride co-hexafluorophosphate (PVDF-HFP) as the base polymer and trioctyldodecylphosphonium bis(2,4,4-trimethylpentyl)phosphinate) (P88812BTMPP) as extractant carrier, and its utilization for the Co(II) sorption and transport. PIM with 40 wt% ionic liquid content showed a high sorption efficiency (>95 %) for 100 mg/L Co(II) feed with 0 and 5 mol/L HCl. Likewise, the transport experiment was achieved with Co(II) in 5 mol/L HCl as feed solution and 2 mol/L H2SO4, which exhibited excellent performance with a recovery factor of more than 85 %. The effect of various parameters on the efficiency of Co(II) sorption and transport was examined systematically. The kinetic and thermodynamic studies revealed that Co(II) sorption onto PIM was chemisorption in nature. Interestingly, the adsorption mechanism of Co(II) was found to be dependent upon the HCl concentration, resulting in two different mode of sorption mechanisms. Moreover, Co(II) desorption (>95 %) was achieved effectively, using 2 mol/L H2SO4. The recycling experiments suggested that PIM could be reused effectively without significant performance loss after six consecutive sorption-stripping cycles. Therefore, the reported PIM holds a good potential as a sorbent of critical metals, such as cobalt, due to its cost-effectiveness, excellent performance in batch-sorption and continuous transport processes, as well as good regeneration properties. To the best of our knowledge, this is the first report on Co(II) transport, employing a membrane transport system with a novel phosphonium-based ionic liquid.

Iron-carbon micro-electrolysis coupled to heterotrophic nitrification aerobic denitrification treating low carbon/nitrogen mariculture wastewater.

Considering the unsatisfied nitrogen (N) and phosphorus (P) treatment performance of mariculture wastewater caused by low carbon/nitrogen (C/N), a novel iron-carbon (Fe-C) micro-electrolysis coupled to heterotrophic nitrification aerobic denitrification (HNAD) process was proposed to enhance the N and P elimination. Results revealed that total nitrogen (TN) removal and total phosphorus (TP) removal efficiencies in Fe-C filter with HNAD (R-Fe) increased by 76.1% and 113.3% compared to filter packed with ceramsite (R-C). Fe-C micro-electrolysis reaction led to the decrease of microbial diversity and richness, the enrichment of heterotrophic nitrification aerobic denitrification bacteria (HNADB) and HNAD genes (napA and napB) by 7.3 times and 56.3%. Besides, a synergistic effect existed that Fe-C substances not only further accumulated main functional genes associated with the transformation of N, carbon (C) and iron (Fe), but also indirectly enhanced electron transport system activity and ATP generation, thus resulting in elevating TN removal.

Need for an Improved Criteria to Evaluate Accessibility to Public Bus Transport Systems from a Sustainable Perspective

Need for an Improved Criteria to Evaluate Accessibility to Public Bus Transport Systems from a Sustainable Perspective

Suspended sediment (SPS) triggers nitrogen retention by altering microbial network stability and electron transport behavior during the aerobic-anoxic transition.

NO3--N transformation, the vital biological process, determines nitrogen removal and retention in aquatic environment. Suspended sediment (SPS) ubiquitous in freshwater ecosystems can accelerate the transitions from aerobic to anoxic states, inevitably impacting NO3--N transformation. To elaborate on the microbial mechanism by which SPS content affected NO3--N transformation, we explored nitrogen removal and retention, microbial communities, co-occurrence networks, and electron transfer behavior under different SPS content during the aerobic-anoxic transition. We found that higher SPS concentration obviously increased NO3--N transformation rates but slightly affected TN removal, as the optimal SPS concentration boosting dissimilatory nitrate reduction to ammonium (DNRA) helped retain nitrogen during the transition. Microbial analysis suggested that the up-regulated SPS content slightly affected dominant bacteria abundance while progressively enhancing the essentiality of deterministic selection in microbial assembly and making microbial network more stable. Further investigations indicated that SPS content indirectly affected nitrogen retention via altering microbial network stability and electron transport system activity (ETSA) rather than bacterial abundance. Notably, elevating ETSA caused by SPS content directly promoted the potential for NO3--N being transformed through DNRA, enhancing nitrogen accumulation during the aerobic-anoxic transition. These results would provide supporting theories for the ecological restoration of micro-polluted water with higher SPS content.