Hasil untuk "Transportation and communication"

Dimitrios Pliatsios, Panos Sarigiannidis, Thomas D. Lagkas et al.

Supervisory Control and Data Acquisition (SCADA) systems are the underlying monitoring and control components of critical infrastructures, such as power, telecommunication, transportation, pipelines, chemicals and manufacturing plants. Legacy SCADA systems operated on isolated networks, that made them less exposed to Internet threats. However, the increasing connection of SCADA systems to the Internet, as well as corporate networks, introduces severe security issues. Security considerations for SCADA systems are gaining higher attention, as the number of security incidents against these critical infrastructures is increasing. In this survey, we provide an overview of the general SCADA architecture, along with a detailed description of the SCADA communication protocols. Additionally, we discuss certain high-impact security incidents, objectives, and threats. Furthermore, we carry out an extensive review of the security proposals and tactics that aim to secure SCADA systems. We also discuss the state of SCADA system security. Finally, we present the current research trends and future advancements of SCADA security.

Yunpu Zhang, Changsheng You, Ruichen Zhang et al.

Prior studies on mixed near-field and far-field communications have focused exclusively on single-cell scenarios, where both near-field and far-field users are served by the same base station (BS), leading to intra-cell mixed-field interference. In this paper, we consider a more general and practical multi-cell mixed-field scenario consisting of multiple cells, each serving multiple users, thus resulting in more complex inter-cell mixed-field interference. To address this new challenge, we propose leveraging rotatable antenna (RA) technology to enhance multi-cell mixed-field communication performance by exploiting the additional spatial degree-of-freedom introduced by RA rotation to mitigate interference in an efficient way. Specifically, we study an RA-enabled multi-cell mixed-field communication system in which each BS is equipped with an RA array to serve its associated users. We formulate a network-wide sum-rate maximization problem that jointly optimizes the transmit beamforming and the rotation angles of the RA arrays, subject to per-BS power constraints and admissible array rotation limits. To gain useful insights into the role of RAs in multi-cell mixed-field communications, we first analyze a special case with a single user per cell. For this case, we obtain a closed-form expression for the rotation-aware inter-cell mixed-field interference using the Fresnel integrals and analytically show that RA rotation can effectively mitigate such interference, thereby substantially improving system performance. For the general case with multiple users per cell, we develop an efficient double-layer algorithm: the inner layer optimizes the transmit beamforming at each BS via semidefinite relaxation and successive convex approximation; while the outer layer determines the rotation angles of the RA arrays using particle swarm optimization.

M. Boban, A. Kousaridas, K. Manolakis et al.

The ultimate goal of next-generation vehicle-toeverything (V2X) communication systems is enabling accident-free, cooperative automated driving that uses the available roadway efficiently. To achieve this goal, the communication system will need to enable a diverse set of use cases, each with a specific set of requirements. We discuss the main usecase categories, analyze their requirements, and compare them against the capabilities of currently available communication technologies. Based on the analysis, we identify a gap and indicate possible system designs for the fifth-generation (5G) V2X that could close the gap. Furthermore, we discuss an architecture of the 5G V2X radio access network (RAN) that incorporates diverse communication technologies, including current and cellular systems in centimeter wave (cm-wave) and millimeter wave (mm-wave), IEEE Standard 802.11p [1], and vehicular visible light communications (VVLC). Finally, we discuss the role of future 5G V2X systems in enabling more efficient vehicular transportation: from improved traffic flow and reduced intervehicle spacing on highways to coordinated intersections in cities (the cheapest way to increasing the road capacity) to automated smart parking (no more visits to the parking garage!), all of which will ultimately enable seamless end-to-end personal mobility.

Zhenning Li, Hao Yu, Guohui Zhang et al.

Inefficient traffic control may cause numerous problems such as traffic congestion and energy waste. This paper proposes a novel multi-agent reinforcement learning method, named KS-DDPG (Knowledge Sharing Deep Deterministic Policy Gradient) to achieve optimal control by enhancing the cooperation between traffic signals. By introducing the knowledge-sharing enabled communication protocol, each agent can access to the collective representation of the traffic environment collected by all agents. The proposed method is evaluated through two experiments respectively using synthetic and real-world datasets. The comparison with state-of-the-art reinforcement learning-based and conventional transportation methods demonstrate the proposed KS-DDPG has significant efficiency in controlling large-scale transportation networks and coping with fluctuations in traffic flow. In addition, the introduced communication mechanism has also been proven to speed up the convergence of the model without significantly increasing the computational burden.

Max T. M. Ng, Roman Engelhardt, Florian Dandl et al.

This paper develops a semi-on-demand transit feeder service using shared autonomous vehicles (SAVs) and zonal dispatching control based on reinforcement learning (RL). This service combines the cost-effectiveness of fixed-route transit with the adaptability of demand-responsive transport to improve accessibility in lower-density areas. Departing from the terminus, SAVs first make scheduled fixed stops, then offer on-demand pick-ups and drop-offs in a pre-determined flexible-route area. Our deep RL model dynamically assigns vehicles to subdivided flexible-route zones in response to real-time demand fluctuations and operations, using a policy gradient algorithm - Proximal Policy Optimization. The methodology is demonstrated through agent-based simulations on a real-world bus route in Munich, Germany. Results show that after efficient training of the RL model, the semi-on-demand service with dynamic zonal control serves 16% more passengers at 13% higher generalized costs on average compared to traditional fixed-route service. The efficiency gain brought by RL control brings 2.4% more passengers at 1.4% higher costs. This study not only showcases the potential of integrating SAV feeders and machine learning techniques into public transit, but also sets the groundwork for further innovations in addressing first-mile-last-mile problems in multimodal transit systems.

Raghavan Srinivasan, Joseph Szmerekovsky

<i>Background:</i> Over the past decade, the growth of ecommerce and omnichannel order fulfillment has led to a spike in last-mile delivery services. Last-mile delivery being the most expensive portion of the supply chain has resulted in process improvement initiatives by industry and academia targeting lower operational costs. <i>Methods:</i> In this study, we use simulation to account for the daily randomness regarding order quantities with missed deliveries being rolled over to the next period and attrition of the capacities used to meet the demand for each period. Further, to alleviate the impact on operations due to attrition, we consider the use of automation as a replacement for permanent capacity. <i>Results:</i> From the simulation results, we observe that the negative operational impact of employee turnover can be overcome with a combination of delivery robots and crowdsourcing with a payback period as short as 1.55 years. <i>Conclusions:</i> Optimal resource allocation is further refined by the use of simulation. The use of advanced automation such as robots seems to be a viable option for businesses to lower operational costs for some scenarios.

Grakovski Alexander, Ostrovenec Nikita, Gercev Ivan et al.

This paper presents a distortion compensation algorithm for multi-camera systems that does not require specialized calibration targets. A review of classical distortion models as well as modern calibration approaches (such as OpenCV) is provided. A modification of the distortion compensation algorithm is proposed, and an experimental comparison with the classical Brown–Conrady model is conducted using data from cameras equipped with the Sony IMX462 sensor. The results show that the proposed algorithm achieves projection rectification comparable to target-based calibration while preserving a wide field of view. This opens up opportunities for applying the method in wearable monitoring systems, panoramic image creation, and pipeline inspection, where the use of calibration targets is challenging.

G. Shobana, A. Thillai Nathan, Dhev Sabharish Sivakumar et al.

Abstract Vehicular ad hoc networks (VANET) are revolutionizing transportation by enabling real-time communication between vehicles and roadside infrastructure, enhancing safety and efficiency through the exchange of traffic updates, road conditions, and critical data. However, VANET faces significant security threats, including Sybil, black hole, and wormhole attacks, where malicious nodes manipulate network communication, leading to misinformation and disruptions. This research proposes a novel hybrid model, GBiL, integrating gated recurrent unit (GRU) and bidirectional long short-term memory (BiLSTM) to detect and mitigate such attacks. At the core of this architecture, an intrusion detection system (IDS) is combined with a trust detection module to assess the trustworthiness of network nodes using real-time data. The IDS employs a hybrid approach for efficient intrusion detection, leveraging particle swarm optimization (PSO) after feature selection. To ensure a balanced dataset, data augmentation is applied using SMOTETomek, a combination of Synthetic Minority Over-sampling Technique (SMOTE) and Tomek Links. Real-time simulations using NS-3 and SUMO with real-world mapping from OpenStreetMap validate the system’s effectiveness in a realistic urban network environment by generating a dataset called VANET Attacks (VA) dataset. This comprehensive approach strengthens VANET security against multiple attack vectors. The proposed GBiL model achieves high performance, with an accuracy of 96.01% and a false alarm rate of just 0.04%. This research significantly enhances VANET security by integrating sophisticated detection techniques, data augmentation, and real-time trust evaluations, establishing a robust foundation for more secure and reliable autonomous transportation through improved vehicular communication networks.

Li Mi, Xi Jianchao, Ye Sui et al.

Tourism corridors are a new type of activity carrier with the advent of self-driving tours and transportation integration in tourism. Tourism corridors can help to reconstruct spatial tourism patterns and optimize regional tourism industry structures. Performing tourism corridor maturity assessments can be used to guide corridor construction. However, few studies have included both linear corridor maturity assessments and obstacle factors. Using the entropy weight method and obstacle degree model, we constructed an evaluation index system for the Sichuan-Tibet tourism corridor maturity based on four aspects: resource endowment, reception level, infrastructure, and security guarantee. The obstacle factors of the corridor were combined with the results obtained from the evaluation system and discussed. The Sichuan-Tibet tourism corridor is currently at a relatively low maturity level and sections with low maturity levels and below account for 89.04% of the total mileage. Owing to the fact that the economic development level of Tibet lags behind that of Sichuan, as well as the geographical complexity, the low maturity sections were mostly concentrated in Tibet. The maturity of the tourism corridor exhibited a "high-low-high" spatial distribution, in which the high-maturity regions were located in Chengdu and Lhasa at both ends of the corridor. In contrast, the low-maturity regions were mainly concentrated in the Bomi-Mangkang and Litang-Yajiang sections in the central part of the corridor. The main obstacles to the maturity of the Sichuan-Tibet tourism corridor had effects that decreased in the order of reception level > infrastructure > security guarantee > resource endowment. Based on the specified indicators, service facilities, tourist catering, medical level, entertainment facilities, and communication conditions were the main obstacles. The main obstacle factors in each section of the tourism corridor differed and were divided into resource obstacle, reception facility obstacle, and security obstacle sections. Among these, security obstacle factors were present in most sections. Sections with differing obstacles should therefore take measures according to local conditions to reduce the impacts of their obstacles. This study addressed the spatial evaluation of linear corridor development and construction, which can be used to evaluate the maturities of other tourism corridors and provide support for the development and construction of the Sichuan-Tibet tourism corridor.

Zachary A. K. Frosch, Clark Meshack, Caitlin Meeker et al.

ABSTRACT Background Autologous stem cell transplantation (ASCT) and chimeric antigen receptor T‐cell therapy (CAR‐T) can provide significant clinical benefit, but are not equally available to all patients. Oncologist continuity and trust are important to patients, and may act as barriers to receipt of therapy. However, detailed data are lacking on the mechanism by which these might affect receipt of therapy, or how this barrier may be overcome. Methods We conducted a qualitative interview study with patients with non‐Hodgkin lymphoma (NHL), classic Hodgkin lymphoma (cHL) or multiple myeloma (MM) eligible for or treated with ASCT/CAR‐T. Participants were recruited from a multi‐site academic health system that includes a safety net hospital considered to be one of the most racially inclusive in the country. Interviews were independently coded by two trained coders. Results Forty patients participated. Half were female, 65% had multiple myeloma, 45% identified as Black or African American, 22.5% had an income less than $30,000 and 33% were insured with Medicaid. In addition to treatment‐specific factors and logistical factors such as housing and transportation, patients identified the need to establish care and trust with a new provider as potential barriers to receipt of therapy. This process could be facilitated by the perception of strong communication and existing relationships between patients' established and new providers. Conclusions In addition to logistical and clinical factors, several factors centering around existing and newly required patient‐provider relationships may influence patients' acceptance of ASCT/CAR‐T. Acceptance may be enhanced by addressing relationship‐based barriers in a manner that emphasizes continuity and helps build trust with a new provider, such as by explicitly demonstrating seamless communication among care teams.

Sri Subanti, Arif Rahman Hakim, Mas Rahmah et al.

IntroductionMaintaining the quality of life for the aging urban population is becoming more and more crucial since this is becoming a global phenomenon. Cities need to be comfortable and accommodate facilities according to the needs of older adults to support the aging of the urban older adults while improving their quality of life. This paper aims to determine the value of a city’s quality of life in relation to its urban facilities and services, as well as to examine the relationship between quality of life and the aging population in Indonesian cities.MethodsThis study measures the quality of life using a hedonic model approach, which determines the price of each component of city comfort, both as facilities and services. We also employed an empirical model to investigate the relationship between quality of life and the aging population in Indonesian cities.ResultsOur research shows that the majority of Javan cities have high quality of life values because older residents have lived there for a long time, they can access facilities and services that meet their needs as they age.DiscussionThe quality of life plays an important role in the number of urban older adults, with health facilities, older adults-friendly transportation, security guarantees, and communication accessibility having a significant effect on the increase in urban older adults in Indonesia. The city governments should provide urban facilities that understand the characteristics and adjust to the needs of older adults.

Dejan Papič, Damjan Maletič, Robert Klinc

Infrastructure asset management faces major challenges in maintaining ageing assets while adapting to technological changes and budget constraints. This paper addresses the lack of a clear definition for “operations and maintenance (O&M) capability” in the context of infrastructure asset management. The authors conducted a systematic literature review extracting 13 capability definitions across multiple domains, followed by semi-structured interviews with 11 senior industry experts from diverse infrastructure sectors, analysing data through List–Group–Label methodology. The research resulted in a comprehensive yet practical definition of O&M capability and identified its key components through an expert-refined framework that balances comprehensiveness and simplicity. This definition provides practitioners and researchers with a common understanding that enables better adaptation of infrastructure to rapid technological change, better utilisation of data and a stronger focus on citizen needs. The framework enables cities and infrastructure operators to systematically assess, develop, and communicate their O&M capabilities, supporting standardised approaches to capability planning and performance measurement across smart city infrastructure projects. The framework creates a foundation for future research and practical applications in O&M and stimulates further development of approaches to build capabilities for smart city infrastructure.

John E. Tyworth

<i>Background</i>: Foundational research on the gamma distribution and inventory control highlighted its flexibility and practicality for managing fast-moving finished goods. Nonetheless, concerns remain about conventional statistical approximations of lead-time demand (LTD) distributions. Real-world lead times often result in nonstandard LTD forms, and traditional methods may introduce parameter mismatches under nonclassical conditions. Despite these challenges, this research demonstrates that a gamma LTD approximation is an effective method for managing these goods. <i>Methods</i>: This study employs numerical experiments to assess accuracy at high service levels, focusing on errors in system cost and product availability. Three propositions are validated: (1) a standard distribution generally characterizes the demands of fast-moving items; (2) demand variability systematically modifies the form of nonstandard LTD distributions, enhancing accuracy; (3) nonclassical conditions generally improve the accuracy of properly parameterized gamma approximations. A purposive sample of disruptive lead-time distributions found in global maritime supply chains drives numerical experiments. <i>Results</i>: Externally validated evidence provides the following findings within our study context: (1) a nonstandard lead-time distribution does not necessarily result in a similar LTD distribution, as it also depends on demand variability; (2) demand variability positively affects the form of a nonstandard LTD distribution under conventional conditions, with nonclassical conditions enhancing this effect; (3) the shape transformations almost always improve the accuracy of a gamma approximation. <i>Conclusions</i>: A gamma LTD approximation can manage inventory for fast-moving finished goods effectively, even with disruptive lead times under both conventional and nonclassical conditions.

Aygun Baltaci, E. Dinc, Mustafa Ozger et al.

Electrification turned over a new leaf in aviation by introducing new types of aerial vehicles along with new means of transportation. Addressing a plethora of use cases, drones are gaining attention in the industry and increasingly appear in the sky. Emerging concepts of flying taxi enable passengers to be transported over several tens of kilometers. Therefore, unmanned traffic management systems are under development to cope with the complexity of future airspace, thereby resulting in unprecedented communication needs. Moreover, the long-term increase in the number of commercial airplanes pushes the limits of voice-oriented communications, and future options such as single-pilot operations demand robust connectivity. In this survey, we provide a comprehensive review and vision for enabling the connectivity applications of aerial vehicles utilizing current and future communication technologies. We begin by categorizing the connectivity use cases per aerial vehicle and analyzing their connectivity requirements. By reviewing more than 500 related studies, we aim for a comprehensive approach to cover wireless communication technologies, and provide an overview of recent findings from the literature toward the possibilities and challenges of employing the wireless communication standards. After analyzing the proposed network architectures, we list the open-source testbed platforms to facilitate future investigations by researchers. This study helped us observe that while numerous works focused on cellular technologies to enable connectivity for aerial platforms, a single wireless technology is not sufficient to meet the stringent connectivity demands of the aerial use cases, especially for the piloting operations. We identified the need of further investigations on multi-technology heterogeneous network architectures to enable robust and real-time connectivity in the sky. Future works should consider suitable technology combinations to develop unified aerial networks that can meet the diverse quality of service demands of the aerial use cases.

Qian Mei, H. Xiong, Jinhao Chen et al.

As an extension of traditional vehicular ad hoc networks, the Internet of Vehicles (IoV) enables information collection and dissemination, which brings a lot of convenience and benefits to the intelligent transportation systems. However, the booming IoV confronts a few challenges in the aspects of vehicle location privacy preservation and the authenticity of the transmitted information. In order to meet these challenges, we propose an efficient certificateless aggregate signature scheme with conditional privacy preservation in this article. Our scheme utilizes the technique of full aggregation to reduce the bandwidth resources and computing overhead. Besides, the conditional privacy preservation in IoV system is realized by using pseudonym mechanism. We demonstrate that the proposed scheme is secure against the Type-I and Type-II adversaries in the random oracle under the computational Diffie–Hellman assumption. In addition, the proposed scheme is compared with related works from aspects of computation cost, communication efficiency, and security requirements. The comparison results show that the proposed scheme is efficient, and it is suitable for resource-constrained environments.

Judy E. Scott, C. Scott

Just as the mobile phone allowed developing countries to leapfrog technology in personal communication, the delivery drone has the potential to have the same effect on traditional transportation infrastructure. Inaccessible roads no longer will prevent delivery of blood, medications or other healthcare items. This paper reviews the current status of innovative drone delivery with a particular emphasis on healthcare. The leading companies in this field and their different strategies are studied. Further we review the latest decision models that facilitate management decision making for operating a drone fleet. Our contribution in this paper of two new models associated with the design of a drone healthcare delivery network will facilitate more timely, efficient and economical drone healthcare delivery to potentially save lives.

Xuting Duan, Huiwen Yan, Daxin Tian et al.

The development and applications of mobile communication technologies in intelligent autonomous transportation systems have led to an extraordinary rise in the mount of connected and autonomous vehicles (CAVs). Ensuring the security of in-vehicle communication data is the basis for the safety of cooperative transportation systems. An in-vehicle controller area network (CAN) bus is an important issue in in-vehicle security, and some hackers have mastered remote vehicle control methods through the CAN bus network. This paper proposes an improved isolation forest method with data mass (MS-iForest) for data tampering attack detection, in which we use data mass instead of the number of divisions and give an anomaly score ranking to quantify the degree of anomalies. This method is promising to be used as part of the intrusion detection system, like a security component in the onboard gateway, which can effectively avoid the data tampering attacks. We compare the proposed method with other anomaly detection schemes based on the data collected from an in-vehicle simulated dataset and two standard datasets. The experiment results show that the proposed method performs better than the other anomaly detection schemes in terms of the area under the receiver operating curve (AUC).

Bing Yan, Peng Shi, C. Lim

In this article, a distributed adaptive event-triggered formation control strategy is proposed for unified nonlinear heterogeneous multiagent systems under uncertainties and disturbances to achieve time-varying formations. To reduce the frequency of data transmission, a distributed dual adaptive observer with an event-triggered strategy is developed to estimate the states of a reference exosystem. Without incurring prior global information about a communication graph, a novel robust formation controller, with dynamic distributed compensators for uncertainties and disturbances, is designed based on an observer result and a nonlinear internal control principle. Finally, both simulation and experiment are conducted for tracking and patrolling formation to verify the effectiveness of the proposed formation control strategy and its robustness. Note to Practitioners—This article addresses the collaborative formation problem of multiagent systems that has potential applications in transportation and disaster relief. The design of robust and energy-saving coordination strategies is challenging in heterogeneous multivehicle systems. The proposed distributed method is suitable for large-scale uncertain heterogeneous systems, and the use of the dual adaptive event-triggered strategy reduces the data transmission rate.

Hai-xia Peng, Le Liang, X. Shen et al.

Vehicular communications, referring to information exchange among vehicles, infrastructures, etc., have attracted a lot of attention recently due to great potential to support intelligent transportation, various safety applications, and on-road infotainment. In this paper, we provide a comprehensive overview of a recent research on enabling efficient and reliable vehicular communications from the network layer perspective. First, we introduce general applications and unique characteristics of vehicular communication networks and the corresponding classifications. Based on different driving patterns, we categorize vehicular networks into manual driving vehicular networks and automated driving vehicular networks, and then discuss the available communication techniques, network structures, routing protocols, and handoff strategies applied in these vehicular networks. Finally, we identify the challenges confronted by the current vehicular networks and present the corresponding research opportunities.

Hong Zhong, Shunshun Han, Jie Cui et al.

Abstract Vehicular Ad-hoc Network (VANET) is the fundamental of intelligent transportation systems. Security and privacy are the important issues needed to be addressed. Existing schemes for privacy-preserving vehicular communications face many challenges, such as strong assumption on ideal tamper-proof device (TPD) and reducing the cost of computation and communication. In order to overcome the challenge, we propose a privacy-preserving authentication scheme with full aggregation in VANET, using certificateless aggregate signature to achieve secure vehicle-to-infrastructure (V2I) communications. The technique of aggregate signature can achieve message authentication and greatly save the bandwidth and computation resources. In addition, we use pseudonym to realize conditional privacy preserving and a trace authority (TRA) is responsible for generating pseudonym and tracking the real identity during the communication if it is necessary. When a vehicle enters an area under a new road side unit (RSU)’s coverage, we pre-calculate some data for once, thus the computation cost in sign phase can be reduced. The length of aggregated signature is constant which reduces the communication and storage overhead.