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During the modernization era, the power generation has been shifted to decentralized manner with more renewable distributed generation (DG) units integration at the distribution level in disperse manner. These DG units have to be properly placed for performance enhancement of distribution system. In this paper, the performance of radial distribution system has been enhanced by optimally allocating biomass type DG in the network. Here, a combination of sensitivity index method and a recently developed nature inspired algorithm known as Artificial Gorilla Troops Optimizer (AGTO) algorithm has been used for optimal siting and sizing of DG units in the 33- and 69-bus radial distribution network by taking real and reactive power loss minimization, voltage profile improvement and voltage stability enhancement as the primary objectives along with the system operational constraints. The composite type of load model has been considered in this paper. Out of all the load buses, some severe buses are selected by index vector sensitivity method. AGTO has been applied on these selected buses for appropriate allocation of DG. The effectiveness of this algorithm has been compared with Grey Wolf Optimization (GWO) algorithm and other reported results. The concept of load growth has also been studied in this work. [ABSTRACT FROM AUTHOR]

The DC bus current ripple is a critical performance parameter affecting the operation of current source inverters (CSIs). In high-power applications, CSIs often operate at lower switching frequencies to minimize losses. However, maintaining low levels of DC bus current ripple necessitates the use of large inductors on the DC side, which increases the size, weight, and cost of the system. This paper first explores the inherent limitations of conventional CSI designs. Subsequently, it proposes a hierarchical coordinated switching modulation strategy based on the H7 current source inverter (H7-CSI) to address the issue of DC bus current ripple. By segmenting the zero-vector states, the proposed method fully utilizes the modulation freedom of the H7-CSI, achieving high-frequency chopping effects on the DC-side current. Experimental results show that the new modulation strategy reduces the amplitude of DC bus current ripple to 43% of that achieved by conventional CSIs under similar switching loss conditions. Furthermore, the dynamic performance of the proposed scheme remains consistent with conventional CSIs. Spectrally, this method exhibits improved performance in the low-frequency range and slightly degraded performance in the high-frequency range, although the latter remains within acceptable limits. [ABSTRACT FROM AUTHOR]

The independent DC bus structure multiport power electronic transformer (IDBS-MPET) is a novel power electronic transformer designed to integrate multiple DC sources and DC loads. Due to the configuration of DC ports, which are directly constructed by the parallel connection of dual active bridge (DAB) converters, the distribution of DC sources and DC loads among the three phases becomes unbalanced. In cases where the load power at certain ports is too high, this imbalance may lead to the over-modulation of the front-end H-bridge (HB). Since the output power at a certain port in the IDBS-MPET is constrained by the loads at other ports, this paper proposes a multiport steady-state power flow allocation method. This method establishes the load sensitivity correlation factor to enable all the ports to adjust power cooperatively based on it. By applying the proposed steady-state power flow allocation method, iterative calculations continuously update the priority of all the ports and their load sensitivity correlation factors. This process ensures that the power flow converges to a steady-state solution. Simulation results for two different IDBS-MPETs demonstrate that the power flow at all the ports effectively meets load requirements, while the front-end HB avoids over-modulation, ensuring the safe and stable operation of the IDBS-MPET. The results validate the effectiveness of the proposed steady-state power flow allocation method. [ABSTRACT FROM AUTHOR]

Phasor measurement units (PMUs) provide synchronized measurements to enhance power system monitoring, strategically placed to achieve full network observability with minimal cost. In this paper, the PMU placement problem for critical buses is addressed using integer linear programming, taking into account both PMU contingencies and the impact of zero-injection buses. The primary contribution is the development of a multi-stage approach to place PMUs on critical buses. Moreover, it is demonstrated that considering PMU contingencies inherently accounts for line contingencies. Furthermore, a new performance metric, the Bus Coverage Index (BCI), is proposed to evaluate the effectiveness of the placement strategy. This index overcomes the limitations of existing indices, such as the Sum of Redundancy Index (SORI) and Bus Observability Index (BOI). The results are tested on various IEEE benchmark systems under four different cases, showing significantly improved results in terms of network observability and minimized number of PMUs. In Case 1, SORI values improved significantly for the IEEE 7 and IEEE 118 bus systems, while in Case 2, enhancements were observed in the IEEE 30 and IEEE 118 systems. Case 3 demonstrated consistency in results across systems. Notably, in Case 4, the number of required PMUs was reduced in the IEEE 30, IEEE 57, IEEE 118, and New England 39 bus systems, with complete network observability. [ABSTRACT FROM AUTHOR]

Summary: As the traditional transformerless three‐phase (TTP) inverters have the shoot‐through and common mode leakage current (CMLC) problems, as well as not being able to realize the buck‐boost conversion, topology derivation and control method of high‐reliability buck‐boost double‐grounded TTP inverters are proposed. These topologies consist of two‐port or three‐port converters with boost capability and three dual‐buck inverters. The two‐port or three‐port converters with boost capability provide the positive and negative bus voltages for the three dual‐buck inverters, realizing the boost conversion. The dual‐buck inverters address the shoot‐through problem. The double‐grounded structure is used to solve the CMLC problem. Dead time between switches is not needed, which reduces the complexity of the control system. Detailed topology derivation of the dual‐buck double grounded TTP inverters with boost capability is given. The operating principle, parameters design of the filters, and stability analysis of this inverter are analyzed in detail. Loss analysis of the inverter is given. The simulation and experimental results of a 750‐W TTP inverter are used to verify the theoretical analysis. [ABSTRACT FROM AUTHOR]

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Robust charging schedules for a growing market of battery-electric bus (BEB) fleets are critical to successful adoption. In this paper, we present a BEB charging scheduling framework that considers spatiotemporal schedule constraints, route schedules, fast and slow charging options, and battery dynamics, modeled as a mixed-integer linear program (MILP). The MILP is based on the berth allocation problem (BAP), a method that optimally assigns vessels for service, and is adapted in a modified form known as the position allocation problem (PAP), which assigns electric vehicles (EVs) for charging. Linear battery dynamics are included to model the charging of buses while at the station. To account for the BEB discharges over their respective routes, we assume that each BEB experiences an average kWh charge loss while in transit. The optimization coordinates BEB charging to ensure that each vehicle maintains a state-of-charge (SOC) above a specified level. The model also minimizes the total number of chargers utilized and prioritizes slow charging for battery health. The validity of the model is demonstrated using a set of routes sampled from the Utah Transit Authority (UTA) for 35 buses and 338 visits to the charging station. The model is also compared to a heuristic algorithm based on charge thresholds, referred to as the Qin-modified method. The results show that the MILP framework encourages battery health by assigning slow chargers to BEBs more readily than the Qin-modified method. The MILP utilized one fast charger and six slow chargers, whereas the Qin-modified method utilized four fast chargers and six slow chargers. Moreover, the MILP maintained a specified minimum SOC of 25% throughout the day and achieved the required minimum SOC of 70% at the end of the working day, whereas the Qin-modified method failed to maintain the SOC above 0% without any constraints applied. Furthermore, it is shown that the spatiotemporal constraints are met while considering the battery dynamics and minimizing both the charger count and consumption cost. [ABSTRACT FROM AUTHOR]

Multimodal arterial signal coordination for buses and passenger vehicles can improve arterial travel smoothness and efficiency. However, uncertainty in bus operations requires signal priority at intersections, which impacts coordination and increases stop times for other traffic types. Therefore, this study proposes a stochastic priority-integrated signal coordination (SPIC) method. It includes an offline stochastic programme to determine the arterial signal coordination, i.e. cycle length and offsets, considering the stochastic signal priority, and an online mixed-integer nonlinear programme to determine the signal priority together with the bus arrival and departure times at and from stops and intersections in a connected vehicle environment. A scenario-based heuristic algorithm is proposed to solve the SPIC efficiently. Numerical studies have validated that SPIC can improve the efficiency of buses and passenger vehicles. Sensitivity analyses show that the SPIC effectively reduces delays with fluctuations in the bus travel time, dwell time, and passenger vehicle demands. [ABSTRACT FROM AUTHOR]

Direct current (DC) microgrid has recently gained potential interest since it supports easy integration of distributed generators (DGs) and energy storage devices (ESDs). However, most DGs and ESDs are integrated into the DC bus with the power electronic converter/inverter. Thus, controlling large-scale power electronic-based generators, loads, and ESDs becomes a challenging task. This paper introduces a new control strategy for the DC microgrid to regulate the bus voltage and power sharing among the DGs, ESDs, resistive loads, and constant power loads (CPLs). Each battery's state of charge (SoC) is utilized in the double control loop to determine the charging/discharging speed. Besides, an additional fractional-order proportional-integral voltage compensation loop is introduced to regulate the DC bus voltage. The SoC-based inner loops assist in the automatic balancing of battery charges, while the compensation loop minimizes the DC bus voltage deviation. A detailed small-signal model is derived to design the controller parameter. The optimization approach is applied to the developed model with the objective of reducing the integral square error of the step response. The DC microgrid system with the designed controller is tested with the simulation study. The results depict that the bus voltage deviation is reduced by 63.27% while the SoC balancing is faster for both charging and discharging modes. [ABSTRACT FROM AUTHOR]

Lowering system power losses along with improving voltage profile have been major concerns for researchers for the past few decades. The performance of an electrical distribution system (EDS) is dependent on these two factors. This work's main emphasis is on reconfiguring the radial distribution network (RDN) to diminish system power losses and strengthen the voltage profile. The process of network reconfiguration (NR) involves state transitions of sectionalizing and tie switches while still adhering to the limitations. In this work, the optimal reconfiguration network is determined using the artificial rabbits optimization (ARO) approach. The adopted method is tested using IEEE 119 bus RDN under low, normal, and heavy load conditions. When compared to the current approaches, the adopted methodology produced favorable results. [ABSTRACT FROM AUTHOR]

This paper presents a scheme for the feedforward–feedback longitudinal trajectory tracking control of buses. The scheme is specifically designed to address the periodic and repetitive nature of bus operations. First, the vehicle's longitudinal dynamics are linearized along the iterative axis via full-form dynamic linearization (FFDL), and parameters such as the pseudo-gradient are estimated with data and a projection algorithm to grasp the dynamic characteristics of the system. To better handle complex real-world traffic conditions, we then propose the forward and backward structure. At the same time, the iterative axis design performance index is verified, and the forward partial control law, namely, model-free adaptive iterative learning control (MFAILC), is derived. In order to further enhance the robustness to disturbance and other factors, the control law of the feedback part is designed with active disturbance rejection control (ADRC). A key advantage of this control approach is its sole reliance on the data generated during vehicle operation, without the need for specific information about the controlled vehicle. This feature enables the method to be adaptable to different vehicle types and resilient to various disturbances. Finally, MATLAB simulations are used to verify the practicality of the proposed method. [ABSTRACT FROM AUTHOR]

Modular Multilevel Converters (MMCs) play a crucial role in high-voltage DC (HVDC) systems due to their adaptable control and swift response capabilities. However, AC side faults could introduce asymmetric double-line frequency components into the MMC's circulating current, jeopardizing DC bus stability. Although strategies to mitigate DC side fluctuations are well-established, a detailed comparison of their operational impacts remains unexplored. The operational effects of MMCs under AC side faults are firstly examined in this study, including issues related to grid-connected current asymmetry and DC bus current fluctuations. Subsequently, two targeted control schemes are devised based on the goals of suppressing the double-line frequency components and only the zero-sequence components of circulating current. Through simulation, these approaches are contrasted, delineating their advantages and disadvantages in terms of circulating current suppression, submodules(SMs) capacitance voltage fluctuation, and other performance metrics, which could provide a foundational reference for designing and selecting MMC control strategies under AC side faults. [ABSTRACT FROM AUTHOR]

This study introduces a synthetic resilience indicator as a unified analytical tool to evaluate public transport resilience, assessing performance changes in bus networks against random disruptions. This methodology measures the cumulative impact of disruptions, considering the network's capacity for maintaining planned functionality (robustness and reliability) and recoverability (i.e., route diversity), factoring in network topology, passenger flow, and resource diversity. This paper analyzes the impact of disruptions at network and station levels by applying an index to six benchmark networks. Our findings reveal: (1) networks with high station connectivity maintain robustness and flow; (2) a clear link between flow reduction and alternate routes highlights route diversity's value; (3) interplay between topological and flow-related network attributes underlines the need for an aggregated analytical approach. The proposed index can be used as an optimization goal during route network design; informing operators regarding the impact of design choices on future network properties. [ABSTRACT FROM AUTHOR]

The growing interest in vehicle crashworthiness necessitates efficient methods to predict full-scale crash performance from component-level testing. This study introduces a framework for predicting vehicle crashworthiness using component-level tests. The framework employs a scaling procedure incorporating factors like total energy, deformation mode, and vehicle dimensions. The feasibility of this method was validated both experimentally and numerically in a study on the rollover performance of paratransit buses, utilizing two decades of data from full-scale and component testing of six buses. Wall-to-floor connections, prone to plastic deformation during rollovers, were tested for component bending. A rollover performance index was developed as a scaling procedure, establishing a clear correlation between full-scale and component tests. Additionally, extensive finite element simulations confirmed the framework applicability to numerical simulations, demonstrating its practical use in vehicle crashworthiness evaluations to foster resource-efficient design and reduce dependence on full-scale tests. [ABSTRACT FROM AUTHOR]

The dial‐a‐ride problem (DARP) involves designing vehicle routes to fulfill the door‐to‐door transportation requests of users where the goal is to minimize costs while satisfying transportation requests. In this paper, we introduce the rich heterogeneous DARP, which extends the generalized heterogeneous DARP to consider a fleet of buses and taxis, multiple depots, time windows at pickup and delivery locations, maximum ride and waiting times, and the possibility of an accompanying person. Our approach is based on a real service in Barcelona, and we also consider the variation in trip duration based on the time of day and day of the week. A predictive model is developed using machine learning techniques to estimate trip durations accurately. We apply our proposal to the daily door‐to‐door transportation of people with reduced mobility in Barcelona and demonstrate its superiority in terms of costs and quality of service by using the Gurobi optimizer. Additionally, we provide an analysis of the consequences of varying certain features on the costs and quality of service. [ABSTRACT FROM AUTHOR]

Advances in vehicle intelligence have ushered in the rapid development of intelligent connected vehicles and the emergence of the Internet of Vehicles (IoV), greatly improving the passenger travel experience. However, as a new mode of transport, flexible public transportation presents challenges for operators in terms of reducing costs and improving passenger experiences through complex route planning. The present study introduces B∗ as a heuristic multiobjective route planning algorithm that addresses these challenges. Using the trajectory extraction procedure (TEP) and route assignment procedure (RAP), B∗ filters out inaccessible routes and plans efficient routes on the fly to save money and enhance the passenger experience. Experimental results show that B∗ outperforms traditional methods in terms of shorter driving distances and reduced passenger waiting times, highlighting its potential to optimize bus utilization and improve travel experiences. [ABSTRACT FROM AUTHOR]

With the rapid development of DC power supply technology, the operation, maintenance, and fault detection of DC power supply equipment and devices on the user side have become important tasks in power load management. DC/DC converters, as core components of photovoltaic and energy storage DC systems, have issues with detecting ground faults on the positive and negative input/output buses, leading to difficulties in troubleshooting device malfunctions and potentially endangering user safety. To address these issues, a method for detecting ground faults on the positive and negative buses of a synchronous buck photovoltaic and energy storage DC/DC converter is proposed, which involves the comprehensive measurement of multi-point common-mode voltages. This method collects the input positive bus voltage, output positive bus voltage, switch voltage, and the common-mode voltage at the midpoint of the bridge arm, then sums these after removing the switching harmonics. By analyzing the characteristic differences of the summed voltage under the ground fault modes of the positive and negative input/output buses, characteristic parameters are extracted to establish a ground fault identification method, thereby achieving effective detection of ground faults in the photovoltaic and energy storage DC/DC converter. Finally, the effectiveness of the method proposed in this paper was validated through simulations and experiments. [ABSTRACT FROM AUTHOR]

Smart home power hardware makes it possible to collect a large number of measurements from the distribution grid with low latency. However, the measurements are imprecise, and not every node is instrumented. Therefore, the measured data must be corrected and augmented with pseudo-measurements to obtain an accurate and complete picture of the distribution grid. Hence, we present and evaluate a novel method for distribution grid monitoring. This method uses smart plugs as measuring devices and a feature propagation algorithm to generate pseudo-measurements for each grid node. The feature propagation algorithm exploits the homophily of buses in the distribution grid and diffuses known voltage values throughout the grid. This novel approach to deriving pseudo-measurement values is evaluated using a simulation of SimBench benchmark grids and the IEEE 37 bus system. In comparison to the established GINN algorithm, the presented approach generates more accurate voltage pseudo-measurements with less computational effort. This enables frequent updates of the distribution grid monitoring with low latency whenever a measurement occurs. [ABSTRACT FROM AUTHOR]

This paper describes the outcome of a study to investigate the regional public transport spend in each state of Australia. The objective is to derive a reliable figure for comparison and the core metric used is spend per capita. The study assessed publicly available data on public transport spend, followed by a series of consultations with key staff from state bus associations and governments. The analysis was conducted separately for metropolitan (metro) and regional areas and then the regional data were further examined. While the Northern Territory (NT), Tasmania (TAS) and regional South Australia (SA) completely rely on bus services, Victoria (VIC) stands out as the state with the highest public transport spend per head in regional areas with robust train and bus networks which deliver the highest patronage. Western Australia (WA) is the state with the highest bus transport spend per head ensuring relatively high patronage despite the low population density. The study identifies low public transport patronage in regional areas as being influenced by low spending per capita and poor connectivity. It recommends prioritizing improvements in connectivity, multi-modal networks, and opening school buses to the general public. Additionally, funding strategies should focus more on patronage trends linked to spend rather than overemphasizing population density. Further, the study reveals that publicly available data seldom clearly segregates public transport spending in terms of regional and metro expenditure, which would lead to inefficiencies when assessing spatial equity in public transport provision. [ABSTRACT FROM AUTHOR]

The reliability modeling and optimization of performance sharing systems (PSSs) are of vital importance due to their wide applications. Existing research mainly focuses on evaluating and maximizing the reliability of PSSs. However, in many practical systems, decision‐makers tend to prioritize the average cost of the system over its reliability. This paper studies the resource allocation optimization in common bus PSSs. In such systems, each unit has binary‐state random performance to satisfy the multi‐state random demand. The surplus performance can be shared via a common bus with transmission loss between the common bus and the unit. The performance allocation, performance transmission, and unsupplied demand incur costs. Resource allocation strategies are determined by optimization models considering different objective functions and constraints. Additionally, transmission loss between the common bus and the unit is considered. A genetic algorithm is employed to efficiently find the optimal allocation strategies. Numerical examples prove the effectiveness of the proposed models in improving system reliability and reducing system costs. [ABSTRACT FROM AUTHOR]

In order to reduce bus bunching in overlapping route segments and improve the efficiency of bus operation, a dynamic scheduling model is proposed to adjust bus operation states by adopting a cooperative strategy involving multi‐line bus timetable optimization, arterial signal control, and speed guidance. Based on mixed integer linear programming, an arterial signal coordination model with autonomous public transport vehicles (APTVs) dedicated lanes is developed, which enables APTVs to pass through intersections without stopping under conditions that almost have no effect on regular vehicles (RVs). Based on this, a speed guidance strategy of APTVs under connected environment is proposed. After guiding APTVs into the overlapping route segments at a reasonable interval, the optimization goal of maintaining the independent running headway of each bus line to the maximum extent is realized. The simulation verification based on three actual overlapping lines in Hangzhou shows that only the combination of signal coordination considering the characteristics of APTVs and speed guidance can realize the full benefits of bus operation based on dedicated APTVs lane. [ABSTRACT FROM AUTHOR]

Recent years have witnessed the rapid growth of IoT (Internet of Things). Bluetooth Low Energy (BLE) is one of the most popular wireless protocols to implement IoT applications because of its energy efficiency and low-cost properties. However, the development of BLE applications is time-consuming and exhausting. Users are required to write programs for both sides of a BLE connection using complicated low-level APIs. Moreover, it needs much expertise for developers to set appropriate parameters in accordance to different application requirements, especially when there exist multiple concurrent BLE connections. To address these problems, we propose BLEdge, an edge-centric programming approach for BLE applications with multi-connection optimization. First, we propose a wireless bus abstraction for BLE programming. With this, users can write BLE applications in an edge-centric way, as if the BLE-connected peripherals are physically attached to the edge node. Second, we advocate an optimization approach for BLE connection parameters. This optimization approach considers the time slot collision problem under a multi-connection scenario. We conduct extensive experiments with the nRF52840DK platform. Experiment results show that BLEdge can reduce 62.50% to 90.55% LOC (Lines of Code) when developing BLE applications. Furthermore, our parameter optimization approach can reduce up to 42.23% energy consumption. [ABSTRACT FROM AUTHOR]

We propose ZeroCost-LLC (ZCLLC), a novel shared inclusive last-level cache (LLC) design for timing predictable multi-core platforms that offers lower worst-case latency (WCL) when compared with a traditional shared inclusive LLC design. ZCLLC achieves low WCL by eliminating certain memory operations in the form of cache line invalidations across the cache hierarchy that are a consequence of a core's memory request that misses in the cache hierarchy and when there is no vacant entry in the LLC to accommodate the fetched data for this request. In addition to low WCL, ZCLLC offers performance benefits in the form of additional caching capacity and unlike state-of-the-art approaches, ZCLLC does not impose any constraints on its usage across multiple cores. In this work, we describe the impact of LLC cache line invalidations on the WCL and systematically build solutions to eliminate these invalidations resulting in ZCLLC. We also present ZCLLC-OPT, an optimized variant of ZCLLC that offers lower WCL and improved average-case performance over ZCLLC. We apply optimizations to the shared bus arbitration mechanism and extend the micro-architecture of ZCLLC to allow for overlapping memory requests to the main memory. Our analysis reveals that the analytical WCL of a memory request under ZCLLC-OPT is 87.0%, 93.8%, and 97.1% lower than that under state-of-the-art LLC partition sharing techniques for 2, 4, and 8 cores, respectively. ZCLLC-OPT shows average-case performance speedups of 1.89×, 3.36×, and 6.24× compared with the state-of-the-art LLC partition sharing techniques for 2, 4, and 8 cores, respectively. When compared with the original ZCLLC that does not have any optimizations, ZCLLC-OPT shows lower analytical WCLs that are 76.5%, 82.6%, and 86.2% lower compared with ZCLLC-NORMAL for 2, 4, and 8 cores, respectively. [ABSTRACT FROM AUTHOR]

Copyright of China Rubber Industry is the property of Editorial Office of China Rubber Industry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper proposes a combination approach termed combined approach for dynamic available transmission capacity (CDATC) for the quick and accurate computation of ATC. In this regard, the suggested model makes use of the static enlarged downhill and Newton–Raphson-Seidel algorithm. In this paper, the boundary surface of potential energy and the maximum point of potential energy are also estimated in a manner to ascertain transient stability. A CDATC calculation was developed by combining the static method, transient stability, and online state estimate. When compared to existing DATC approaches, the simulation results on a large-scale real-world system confirm the suitability of the suggested method with faster speed and tighter accuracy. Simulation results on the East Iran network, IEEE 118 bus, and Iowa State 145 bus, all of which have a high penetration of wind farms-showed that the developed CDATC is robust at all operating conditions and can be used online with fewer computational resources. The unique application of state estimation in DATC computation, which enabled the study to produce a more realistic answer even in the face of ambiguity, is an additional value. [ABSTRACT FROM AUTHOR]

The development of intrusion detection systems (IDS) for the in-vehicle Controller Area Network (CAN) bus is one of the main efforts being taken to secure the in-vehicle network against various cyberattacks, which have the potential to cause vehicles to malfunction and result in dangerous accidents. These CAN IDS are evaluated in disparate experimental conditions that vary in terms of the workload used, the features used, the metrics reported, etc., which makes direct comparison difficult. Therefore, there have been several benchmarking frameworks and comparative studies designed to evaluate CAN IDS in similar experimental conditions to understand their relative performance and facilitate the selection of the best CAN IDS for implementation in automotive networks. This work provides a comprehensive survey of CAN IDS benchmarking frameworks and comparative studies in the current literature. A CAN IDS evaluation design space is also proposed in this work, which draws from the wider CAN IDS literature. This is not only expected to serve as a guide for designing CAN IDS evaluation experiments but is also used for categorising current benchmarking efforts. The surveyed works have been discussed on the basis of the five aspects in the design space – namely, IDS type, attack model, evaluation type, workload generation, and evaluation metrics – and recommendations for future work have been identified. [ABSTRACT FROM AUTHOR]

This study thoroughly investigates the NoisyNet Deep Deterministic Policy Gradient (DDPG) for frequency regulation. Compared with the conventional DDPG method, the suggested method can provide several benefits. First, the parameter noise will explore different strategies more thoroughly and can potentially discover better policies that it might miss if only action noise were used, which helps the actor achieve an optimal control strategy, resulting in enhanced dynamic response. Second, by employing the delayed policy update policy work with the proposed framework, the training process exhibits faster convergence, enabling rapid adaptation to changing disturbances. To substantiate its efficacy, the scheme is subjected to simulation tests on both an IEEE three‐area power system, an IEEE 39 bus power system, and an IEEE 68 bus system. A comprehensive performance comparison was performed against other DDPG‐based methods to validate and evaluate the performance of the proposed LFC scheme. [ABSTRACT FROM AUTHOR]

Summary: The second harmonic current (SHC) caused by the instantaneous power of downstream inverter will seriously deteriorate the performance of two‐stage inverter and shorten the life of energy storage device, which narrows the application prospect of two‐stage inverter energy storage system (TSIESS). To reduce the SHC in TSIESS, this paper proposes a strategy of virtual LC series resonant circuit with notch filter (NF‐VLCSRC). This strategy utilizes the virtual impedance technology to achieve the function of a LC series resonant circuit (LCSRC) paralleled to the intermediate DC bus capacitor of the TSIESS, so the output impedance of the DAB converter can become larger than the impedance of the DC bus capacitor at twice fundamental frequency and thus the SHC in the front‐end DAB converter can be reduced effectively without power loss problem caused by the internal resistance of the actual LCSRC. Then, in order to facilitate the implementation and avoid interference of parameter mismatches on system performance, the NF is adopted to realize the VLCSRC strategy based on the frequency characteristics of the introduced virtual impedance. Theory analysis and experimental results are presented to illustrate the effectiveness of the proposed control techniques. [ABSTRACT FROM AUTHOR]

With the vast majority of photovoltaic (PV) power generation linked to the grid, the mainstream maximum power point tracking control cannot provide effective inertia support capability for the system. This paper examines the inertia source and action rules of three typical grid-tied photovoltaic systems under generalized sag control at the physical mechanism level, using the theory of the static synchronous generator model as a guide. It is found that the PV system under generalized sag is also capable of supporting the system through inertia. The boost converter, direct current bus capacitor, and inverter all contribute to the inertia capability of the PV system, but it is necessary to couple the control of the responding link with the grid frequency. The closer the action link is to the grid, the faster the speed of the corresponding grid frequency, but the weaker the inertia effect is provided to the system. The accuracy of the aforementioned analysis is confirmed by the simulation. [ABSTRACT FROM AUTHOR]

The utilization of SPI-Flash in embedded systems is widespread, primarily serving as program storage during the boot process. As a result, the boot process is influenced to some extent by the SPI-Flash controller. This paper presents a lightweight SPI-Flash controller that simplifies the boot process design by establishing a direct connection between the SPI-Flash and AHB-lite bus interface, enabling rapid program execution in RAM instead of directly from the SPI-Flash. Additionally, the controller can function as a bare-metal program downloader for testing the boot process functionality during FPGA-based SoC (system-on-chip) prototype verification. The system-level simulation and FPGA verification results demonstrate that the proposed SPI-Flash controller successfully achieves its intended functional impact in operations to target the Micron N25Q256A SPI-Flash chip, boot process design, and bare-metal program download. The synthesis results under the SMIC 180 nm 1P8M technology process indicate that this SPI-Flash controller exhibits remarkable performance, power consumption, and area utilization. The source code of the proposed lightweight SPI-Flash controller has been uploaded to GitHub as an open-source project. [ABSTRACT FROM AUTHOR]

Transit systems, similarly to cities, can be conceived as living and evolving 'organisms' with ever-changing characteristics. Moreover, transit systems are considered the backbone of today's urban mobility ecosystem and part of a sustainable mobility paradigm. However, in many cases, existing transit systems have not successfully adapted to the prevailing socio-demographic context nor incorporated available technological means. As so, redesigning an effective transit system is a tedious task, and although sustainability objectives have recently been considered in a wide scope, aiming to incorporate multiple concerns in urban transport planning (sometimes just declaratively), elements of transport fairness and equity are often overlooked in the process. This paper proposes a novel holistic framework for optimally planning a realistic transit system that ensures fairness and transport equity for users at the strategic level. The framework is comprised of three main parts: (i) assessing the current sustainability performance of the transit service and infrastructure by tessellating the urban continuum into the distinctive constituent districts, (ii) sustainability, fairness and equity indicators for each district are fitted into closed-form equations useful for formulating a realistic (though strategic) spatial budget allocation process, and (iii) solving a multi-objective optimization, revealing trade-offs among indicators of sustainability, fairness and equity in transit system development, addressed by a multi-objective particle swarm routine. The study is showcased for the case of Cyprus' capital, the city of Nicosia, whose bus public transport system is currently being reconsidered, providing solid evidence on the applicability of the proposed novel analytical framework on large-scale urban conglomerations. [ABSTRACT FROM AUTHOR]

To improve the expandability, seeding accuracy, and operating speed range of the electric drive system (EDS) of precision seeders, this study constructed an EDS based on a controller area network (CAN) bus and designed a motor controller based on a field-orientated control (FOC) algorithm. Full-factorial bench and field tests based on seed spacing (0.1, 0.2, and 0.3 m) and operating speed (3, 6, 9, 12, and 15 km/h) were carried out to evaluate the performance of the EDS. The results of bench tests showed that seeding quality varied inversely with operating speed and positively with seed spacing. The average quality of feed index (QFI) at 0.1, 0.2, and 0.3 m seed spacing in bench tests was 88.38%, 96.67%, and 97.36%, with the average coefficient of variation (CV) being 20.13%, 16.27%, and 13.20%. Analysis of variance confirmed that both operating speed and seed spacing had a significant effect on QFI and CV (p < 0.001). The analysis of motor rotational speed accuracy showed that the relative error of motor rotational speed above 410 rpm did not exceed 2.24%, and the relative error had less influence on the seeding quality. The average QFI was 85.93%, 95.91%, and 96.24%, with the average CV being 21.12%, 15.50%, and 16.49% at 0.1, 0.2, and 0.3 m seed spacing in field tests. The methods and results of this study can provide a reference for the design and optimization of the EDS in a maize precision seeder and provide an effective solution for the improvement of maize yields. [ABSTRACT FROM AUTHOR]

This study uses the approach of Ferson and Siegel, Rev Financ Stud 22:2735–2758 (2009), and Ferson, Siegel and Wang, J Financ Quant Anal, forthcoming, (2024) to examine the unconditional mean–variance efficiency, in the presence of conditioning information (UMV), of ten linear factor models in U.K. stock returns. The study finds that the UMV efficiency of all the multifactor models is strongly rejected in U.K. stock returns in two different sets of test assets. This rejection is mainly driven by allowing dynamic trading in the test assets and factors. The optimal use of conditioning information also has a significant impact in relative model comparison tests. In relative model comparison tests based on UMV efficiency, the best performing model is the eight-factor model of Chib and Zeng, J Bus Econ Stat 38:771–783 (2020) model. [ABSTRACT FROM AUTHOR]

One portion of the distribution system is the distribution feeder. Buses carrying more loads and having long‐distance route lines are significant problems due to the presence of power loss and the increase in the overall cost of the transportation process. Hence, the overall power loss minimization is taken as the major objective. The best sizing and allocation of capacitors in a bank in the distribution line are used to minimize the total loss. BWO technique is utilized in this optimization process. The backward‐forward sweep load flow is used for the computation of the power flow in MATLAB. The sensitive buses have been chosen according to the factor of loss sensitivity (LSF) and using BWO. The validity of the test has been made on the standard IEEE 34 and 85 bus radial distribution system. The simulation results in the 34‐bus radial system are much different from the results of PSO, GWO, WO, and IWO. In the 85‐bus radial system, the results are seen with the outcomes of PSO, WO, and BFOA. In both cases, the results of the proposed technique are found to be better than the existing methods. Therefore, the result shows that BWO can be effective for future selection to improve large distribution networks by sizing and locating the capacitors optimally. [ABSTRACT FROM AUTHOR]

An investigation is reported on bus bunching and its spatiotemporal patterns that considers six bus routes in Kolkata City, West Bengal, India. With historical GPS data as inputs, bunching occurrences are identified using the spatiotemporal–density-based spatial clustering of applications with noise (ST–DBSCAN) algorithm. To determine the impact of bunching on various bus stops, k-means++ clustering was used on top of ST–DBSCAN, and subsequently, spatiotemporal bunching patterns were investigated. Some bus stops are consecutively impacted by bunching; however, others are impacted in an isolated manner. To capture the spatiotemporal propagation of bunching, a new indicator termed the propagation ratio is proposed, which could classify the bunching as propagating or isolated. Bunching occurrences are propagating for some bus routes and isolated for others, which justifies the need to prioritize routes displaying propagating nature. Of interest, bunching is identified on high and low-frequency bus routes, which indicates the need to relook at the operational planning of all the bus routes regardless of their frequency. At times, excessive bunching is detected during lean periods of the day, which suggests the necessity of modifying the dispatching headways that are based on passenger demand during these lean periods. The outcomes from this work further indicate that all the bus stops along a bus route are not equally impacted by bunching. The spatiotemporal cluster plots could successfully capture the initial bunching occurrence points and their variation with time, which could provide an opportunity for the operators to apply time-varying remedial measures. The insights developed from this work could be used advantageously by operators and policymakers for mitigating bus bunching and improving the urban bus service. [ABSTRACT FROM AUTHOR]

Bus lanes are an important measure for improving the quality of bus service and the efficiency of transportation systems. A scientific and reasonable evaluation of the overall traffic operation efficiency of the bus priority road section is helpful to fully understand the improvement effect of the introduction of bus lanes on traffic operation. To comprehensively and objectively evaluate the traffic benefits of bus lanes, the Delphi and grey correlation methods were used to construct a comprehensive weight calculation model of the indicators. The weights of eight traffic benefit evaluation indicators at the two levels of buses and general traffic were calculated, and the weights were then optimized using the target optimization model. Combined with different weight indexes, the evaluation of the traffic benefit level of the bus lane was realized using the matter-element extension model based on the improvement in the sticking progress. The bus lanes of the Daping-Yangjiaping, Huanghuayuan interchange-Luneng turntable, and Dashiba-Hongqihegou routes in the main urban area of Chongqing were used for verification. The results show that the traffic benefits of the three case areas have been improved to a certain extent after the construction of bus lanes, but the benefit level has not changed. Through the analysis of various operating indicators, the weaknesses that affect the traffic efficiency can be obtained, and then the decision-making basis for the implementation and improvement of the bus lane optimization scheme can be provided. [ABSTRACT FROM AUTHOR]

To improve the traffic efficiency of bus at a group of intersections and reduce their delay, this paper develops a speed guidance strategy for buses under travel time control at intersection groups. The approach considers the influence of bus departure time, bus station arrival rate, and bus station dwell time. Simulation experiments are carried out on three consecutive intersections along Jinshan Avenue in Fuzhou, China. Results show that the average travel time of buses, the average delay of buses, and the average delay per capita in the priority direction are reduced by 5.5%, 9.9%, and 9.4%, respectively. The optimal rate of the average number of bus stops reached 15.2%. The indicators of the non-priority direction of social vehicles are not significantly affected. It shows that the efficiency of buses has improved after implementing the speed guidance strategy at the intersection groups without affecting the social vehicles as far as possible. [ABSTRACT FROM AUTHOR]

The sliding window method is commonly used for non-intrusive load disaggregation. However, it is difficult to choose the appropriate window size, and the disaggregation effect is poor in low-frequency industrial environments. To better handle low-frequency industrial load data, in this paper, we propose a vertical non-intrusive load disaggregation model that is different from the sliding window method. By training multiple electrical parameters at a single point on the bus end with the corresponding load data at the branch end, the proposed method, called multiple electrical parameters to point (Mep2point), takes the electrical parameter data sampled at a single point on the bus end as its input and outputs the load data of the target device sampled at the corresponding point. First, the electrical parameters of the bus end are processed, and each item is normalized to the range from 0–1. Then, the electrical parameters are vertically arranged by their time point, and a convolutional neural network (CNN) is used to train the model. The proposed method is analyzed on low-frequency industrial user data sampled at a frequency of 1/120 Hz in the real world. We compare our method with three advanced sliding window methods, achieving an average improvement ranging from 9.23% to 22.51% in evaluation metrics, while showing substantial superiority in the actual decomposed images. Compared with three classical machine learning algorithms, our model, using the same amount of data, significantly outperforms these methods. Finally, we also compared our method with the multi-channel low window sequence-to-point (MLSP) method, which also selects multiple electrical parameters. Our model's complexity is much less than that of the MLSP model, and its performance remains high. The superiority of our model, as presented in this paper, is fully verified by experimental analysis, which can produce better actual load decomposition results from each branch and contribute to the analysis and monitoring of loads in industrial environments. [ABSTRACT FROM AUTHOR]

Induction motors are the most common type of motor in power systems, constituting approximately 70–90% of the dynamic loads, making them significant contributors to system dynamics. In transient voltage stability analysis, dynamic equivalent models are commonly used to simplify the representation of a group of induction motors. This paper presents a method for the grouping and aggregation of induction motors at a common bus. Firstly, grouping rules are provided for clustering induction motors into several subgroups based on the mechanical principles of rotor force and motion, and aggregation rules are provided for aggregating a motor subgroup into a single-unit model based on the relationship between voltage drop and power transmission in distribution networks. Secondly, guided by the grouping rules, high-speed remaining electromagnetic torque and low-speed remaining electromagnetic torque are defined as new clustering indicators, and an adaptive K-means clustering method using silhouette coefficient verification is introduced to obtain the optimal motor subgroups. Thirdly, guided by the aggregation rules, a dynamic equivalent method is further introduced to obtain the equivalent single-unit model from a motor subgroup. Lastly, a transient voltage stability simulation in a typical distribution network is presented to illustrate that the proposed clustering and equivalent methods are more reasonable, accurate, and effective than traditional methods, as the obtained model has better dynamic characteristics and can more accurately reproduce the process of voltage collapse. [ABSTRACT FROM AUTHOR]

Modular vehicles are a novel concept that allows for the coupling and decoupling of different vehicle modules and enables in-motion passenger transfers; it can potentially increase the flexibility of the transportation system. Recent studies have numerically highlighted the potential of using modular vehicles as transit buses to mitigate the bus bunching phenomenon. Building upon this, our study offers a comprehensive and systematic analytical assessment of the bunching-proof capabilities associated with modular buses. Specifically, we examine two sets of cases: those with fixed boarding capacities, where each bus stop processes only one queue for a modular platoon, irrespective of the number of modular vehicles it consists of; and those with flexible boarding capacities, where multiple queues can be served at each stop, enabling all modular units within a platoon to cater to boarding passengers concurrently. For the cases with fixed boarding capacities, we quantify the necessary conditions for successful hysteresis restoration, whereas for the cases with flexible boarding capacities, we discover a notable "bounded bunching property," wherein the bus operation inherently restricts the ongoing deterioration of bunching. Leveraging this property, we propose an innovative proactive bunching mitigation method, called "adaptive pushing strategy," to mitigate bus bunching more proactively. A computer simulation platform is established to validate the theoretical findings and mitigation solutions presented in this study. Funding: Financial support from the National Natural Science Foundation of China [Grant 72061127003], the Shanghai Eastern Scholar Program [Grant QD2020057], the Shanghai Chenguang Program [Grant 21CGA72], and the NYU Shanghai Boost Fund is gratefully acknowledged. Supplemental Material: The online appendix is available at https://doi.org/10.1287/trsc.2023.0224. [ABSTRACT FROM AUTHOR]

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Emissions from transportation are one of the key factors preventing the achievement of carbon peaking and carbon neutrality by 2050, with particular attention to emissions from buses. Specifically, few research has been conducted on the exhaust emissions characteristics of liquified natural gas (LNG) buses under different driving scenarios. This study proposed a framework for predicting exhaust emissions of LNG buses based on the portable emission measurement system and GPS collaborative perception data. Firstly, the emission distribution characteristics of CO2, CO, HC, and NOx from LNG buses in real-world driving were analyzed by visualization methods. Then, the real-time exhaust emissions of LNG buses were predicted based on the temporal fusion transformers model for both urban and suburban sections of Zhenjiang City, and the model validity was verified. The current and past 10 s driving states were used for predicting the emission rate of LNG buses. The results showed that the proposed model outperforms other advanced algorithms in real-time exhaust emissions prediction of LNG buses, with an average R2 value higher than 0.94 and an average MAPE reduction of 14.19%. The error assessment revealed that the emission values and average emission rates are higher when driving in the urban section compared to the suburban section. Among the influencing factors, traffic conditions have the most significant impacts on the exhaust emissions of LNG buses, followed by road conditions and driving states, with relative feature importance of 48.9, 34.8, and 16.3%, respectively. Additionally, the current and past 10 s driving states also significantly influenced real-time predictions. This study provides an essential theoretical reference for reducing exhaust emissions for city buses. [ABSTRACT FROM AUTHOR]

Copyright of Automotive Digest is the property of Automotive Digest Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Multi-axle vehicles (MAVs) are used to transport heavy loads, navigate challenging terrain, and perform specific tasks. However, designing vehicle control systems for such vehicles is challenging. MAVs, such as trucks, buses, military vehicles, and multi-purpose vehicles, require sophisticated control techniques to increase the stability and ride comfort of such vehicles. This paper provides a comprehensive review of standalone control systems and integrated control systems (ICSs) for the steering, driving/braking, and suspension systems of MAVs, with a particular focus on the optimal tyre force distribution (TFD) in ICSs for MAVs. It also discusses various objective functions and optimisation methods used for the TFD. The findings indicate that optimising TFD significantly improves the stability of MAVs. As such, future studies may consider examining optimising three-axis TFD for MAVs to further improve vehicle stability. [ABSTRACT FROM AUTHOR]