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The reliability and safety of locomotives is crucial for efficient train operation. Repeated turbocharger failures in Israel Railways locomotive fleet have raised serious safety concerns. An investigation into the failures revealed that the uncontrolled acceleration and overspeed transients of the turbocharger shaft occurred before the failure. Early detection of potential turbocharger failures by predicting overspeed conditions is critical to the safety and reliability of locomotives. In this study, an enhanced novel algorithm for estimating the Instantaneous Angular Speed (IAS) of the turbocharger and diesel engines is presented to overcome the challenges of transient operating conditions of diesel engines. Using adaptive dephasing, the algorithm effectively isolates critical asynchronous vibration components that are crucial for the early detection of turbocharger failures. This algorithm is suitable for non-stationary speeds and is applicable to any range of rotational speed and rate of change. The algorithm requires the input of the basic parameters of the system, while all other parameters that control the process are determined automatically. The algorithm was developed specifically for the special operating conditions of diesel engines and improves predictive maintenance and operational reliability. The method is robust as it correlates between several characteristic frequencies of the rotating parts of the system. The algorithm was verified and validated with simulated and experimental data. [ABSTRACT FROM AUTHOR]

Because of the higher efficiencies achieved by polygeneration systems compared with conventional generation systems, they have been increasingly adopted to reduce the consumption of resources and consequent environmental damage. Heat dissipated by equipment can be harnessed and reused in a cascade manner. This study applies the Theory of Exergetic Cost (TEC), a thermoeconomic approach, to a high-performance polygeneration system. The system includes a biogas-fueled internal combustion engine, a water–ammonia absorption refrigeration system driven by the engine's exhaust gases, and a set of photovoltaic panels with a cooling system coupled to solar panels and a hot water storage tank. The pieces of equipment are dimensioned and selected according to the energy demands of a hotel. Then, the temperature, pressure, and energy flows are established for each point of the system. Mass, energy, and exergy balances are developed to determine exergy flows and efficiencies. The main component in terms of exergy and operation costs is the engine, which consumes 0.0613 kg/s of biogas, produces 376.80 kW of electricity, and provides thermal energy for the refrigeration system (101.57 kW) and the hot water tank (232.55 kW), considering the average operating regime throughout the day. The levelized costs are 2.69 USD/h for electricity, 1.70 USD/h for hot water (thermal energy tank), and 1.73 USD/h for chilled water (absorption chiller). The thermoeconomic diagnosis indicated that the hot water tank and the engine are the most sensitive to changes in the maintenance factor. Reducing operating expenses by 20% for the tank and engine lowers energy costs by 10.75% for the tank and 9.81% for the engine. [ABSTRACT FROM AUTHOR]

With the advent of several tools and web engines trained for finding journal articles out of billions of research papers on millions of topics in different databases with a high degree of generalizability, it often leads to a loss of specificity. Scientific pursuits need a tool to extract data from selected resources for performing domain-specific tasks. Current algorithms and generalized tools lack specificity and are challenged by errors in analysing data from a bundle of specific documents selected eclectically. Current work addresses the need for such a tool, which focuses on specificity based on users' input keywords and phrases to find relevant information from bundles of articles from the web. Reseractor is based on a customized algorithm, Whitespace, in synergy with output from open-access tools for document image analysis and focused domain data extraction using NLP. The current tool is designed for the material science domain with the features of adopting various generalized and scientific corpora as layers. It is tested on two sets of different bundles of papers and gives an accuracy of 81.12% along with a recall of 78.38% and a precision of 84.06%. Owing to the simple and direct applicability of algorithms, users from other domains can directly use their corpora in algorithms and remodel the tool for their purpose. Current work fulfills the need for domain-specific experimental data extraction stored in organized and structured databases for upcoming computational researchers. [ABSTRACT FROM AUTHOR]

The stick–slip phenomenon, the initial stage when the traction wheel starts sliding on the rail, is a critical operation that needs to be detected quickly to control the traction drive. In this study, we have developed an experimental model that uses acceleration sensors mounted on the wheel to evaluate the amplitude of the stick–slip phenomena. These sensors can alert the driver or assist the traction control unit when a stick–slip occurs. We propose a method to reduce the amplitude of the stick–slip phenomenon using special hydraulic dampers and viscous dampers mounted on the tractive axles of the locomotive to prevent slipping during acceleration. This practical solution, validated through numerical simulation, can be readily implemented in railway systems. The paper's findings can be used to select the necessary sensors and corresponding vibration dampers. By implementing these sliding reducers, a locomotive can significantly improve traction, apply more torque to the wheel, and increase the load of a carrier train, instilling confidence in the efficiency of the proposed solution. [ABSTRACT FROM AUTHOR]

Background: In aged society, health policies aimed at extending healthy life expectancy are critical. Maintaining physical activity is essential to prevent the deterioration of body functions. Therefore, it is important to understand the physical activity levels of the target age group and to know the content and intensity of the required physical activity quantitatively. Especially we focused the role of non-exercise activity thermogenesis and sedentary time, which are emphasized more than the introduction of exercise in cases of obesity or diabetes. Methods: A total of 193 patients from 25 institutions were included. Participants underwent a locomotive syndrome risk test (stand-up test, 2-step test, and Geriatric Locomotive Function Scale-25 questionnaire) and were classified into three stages. Physical activity was quantitatively monitored for one week with 3-axial accelerometer. Physical activity was classified into three categories; (1) Sedentary behavior (0 ∼ ≤ 1.5 metabolic equivalents (METs)), (2) Light physical activity (LPA:1.6 ∼ 2.9 METs), and (3) Moderate to vigorous physical activity (MVPA: ≥3 METs). We investigated the relationship between physical activity, including the number of steps, and the stages after gender- and age- adjustment. We also investigated the relationship between social isolation using Lubben's Social Network Scale (LSNS), as social isolation would lead to fewer opportunities to go out and less outdoor walking. Results: Comparison among the three stages showed significant difference for age (p = 0.007) and Body Mass Index (p < 0.001). After gender-and age-adjustment, there was a significant relation with a decrease in the number of steps (p = 0.002) and with MVPA. However, no relation was observed in sedentary time and LPA. LSNS did not show any statistically significant difference. Moderate to high-intensity physical activity and the number of steps is required for musculoskeletal disorders. The walking, not sedentary time, was associated to the locomotive stages, and this finding indicated the importance of lower extremity exercise. Conclusions: Adjusting for age and gender, the number of steps and moderate to vigorous activity levels were necessary to prevent worsening, and there was no effect of sedentary behavior. Merely reducing sedentary time may be inadequate for locomotive disorders. It is necessary to engage in work or exercise that moves lower extremities more actively. [ABSTRACT FROM AUTHOR]

This paper presents a multibody model of the post-derailment dynamics of a railway vehicle and its impact with a derailment containment wall (DCW) built aside the line and demonstrates the use of the model in the context of the structural sizing of devices intended to mitigate derailment effects. With respect to existing multibody models of railway vehicle dynamics, the innovative features of this model are a new contact model capable to provide a plausible prediction of the derailment process despite a simple and computationally efficient formulation, and the model of the interaction between the derailed vehicle and the impacted derailment containment structure, the latter being described by a Finite Element Model. Results from the model are compared to an established multibody software for a non-derailment case, and then a comparison is performed with a measurement from a derailment experiment published in the scientific literature, finding in both cases satisfactory agreement. The model is then applied to analyse a derailment scenario caused by the sudden failure of an axle for a locomotive vehicle travelling at 300 km/h in a HS curve, deriving the peak values of the impact force and bending moment at the base of the derailment containment wall. [ABSTRACT FROM AUTHOR]

We should drop the marketplace of ideas as our go-to metaphor in free speech discourse and take up a new metaphor of the connected city. Cities are more liveable when they have an integrated mix of transport options providing their occupants with a variety of locomotive affordances. Similarly, societies are more liveable when they have a mix of communication platforms that provide a variety of communicative affordances. Whereas the marketplace metaphor invites us to worry primarily about authoritarian control over the content that circulates through our communication networks, the connected-city metaphor invites us to worry, more so, about the homogenization of the tools and formats through which we communicate. I argue that the latter worry demands greater attention under emerging technological conditions. [ABSTRACT FROM AUTHOR]

This article examines international transactions related to steam locomotives at the beginning of the twentieth century while focusing on Japanese trading companies. In particular, it considers in detail how Japanese trading companies acquired the knowledge and know-how of locomotive trading to carry out their business transactions through a case study of Okura & Co.'s New York branch office. The analysis highlights the following three factors that supported Okura's locomotive trade in New York: first, the company took advantage of business opportunities by collecting information through networks of Japanese contacts in New York and local experts; second, it utilised social and technological infrastructure, including international communication lines, transportation, and financial systems, as key fundamentals of its overseas activities; third, a former oyatoi (hired foreigner) played a critical role as its consulting engineer. In particular, the overseas activities of Japanese trading companies drew heavily on formerly hired foreign engineers, whose technological knowledge and networks became an essential route of knowledge transfer in cross-regional commercial management. These will contribute to the evolution of history related to the starting points of global activities of Japanese trading companies. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Electric Power Science & Technology is the property of Changsha University of Science & Technology 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.)

The article presents the contents of a recently discovered list detailing steam and diesel locomotives used in Poland from 1956 to 1970 on narrow-gauge railways of the State Forests. The document includes information such as the markings of individual locomotives, their manufacturers, production years, technical specifi cations, and operational history on specifi c forest railways. This information is presented in tabular format and supplemented with commentary on locomotive marking practices specifi c to forest railways, as well as a comprehensive literature review. [ABSTRACT FROM AUTHOR]

A certain locomotive coil spring was found to fracture prematurely after only 300,000 km of operation. This work employed a combination of experimental and finite element methods to analyze the failure reasons in detail. Firstly, fatigue crack originated from the first working coil adjacent to the support ring, and the fracture exhibited characteristics of low-cycle high-stress fatigue. Secondly, the chemical composition, microstructure, and microscopic morphology of the failed sample was characterized using inductively coupled plasma emission spectrometry, metallographic microscopy, and scanning electron microscopy, respectively. Mechanical properties of the spring were tested using a Rockwell hardness tester and a single-column pendulum-type impact testing machine. Chemical composition analysis of the failed spring indicated conformity to standards. Microscopic fracture analysis revealed quasi-cleavage fracture features, with noticeable fatigue striations and a small amount of ductile dimples were also found. In the absence of corrosion, the microstructure of the spring showed small secondary cracks and deformation marks near the crack source. Microstructures after corrosion revealed predominantly tempered troostite, and the spring's surface underwent an unexpected decarburization process, resulting in a fully decarburized layer with a depth of approximately 64 μm and a total decarburized layer depth of about 160 μm. The overall hardness of the failed spring was below the relevant technical specifications. Furthermore, based on the results of fracture analysis and finite element analysis, it was determined that the spring encountered abnormal conditions during its service period. Therefore, the premature failure of the spring occurred due to the combined effects of unexpected defects resulting from improper heat treatment and adverse service conditions. Finally, some suggestions and preventive measures are proposed for the spring. [ABSTRACT FROM AUTHOR]

This work is devoted to the study of gas-dynamic processes in the operation of climate control systems in the cabins of vehicles (HVAC), focusing on pressure values. This research examines the issue of assessing the required values of air overpressure inside the locomotive cabin, which is necessary to prevent gas exchange between the interior of the cabin and the outside air through leaks in the cabin, including protection against the penetration of harmful substances. The pressure boost in the cabin depends, among other things, on the external air pressure on the locomotive body, the power of the climate system fan, and the ratio of the input and output deflectors. To determine the external air pressure, the problem of train movement in a wind tunnel is considered, the internal and external fluids domain is considered, and the air pressure on the cabin skin is determined using numerical methods CFD based on the Navier–Stokes equations, depending on the speed of movement. The finite-volume modeling package Ansys CFD (Fluent) was used as an implementation. The values of excess internal pressure, which ensures the operation of the climate system under different operating modes, were studied numerically and on the basis of an approximate applied formula. In particular, studies were carried out depending on the speed and movement of transport, on the airflow of the climate system, and on the ratio of the areas of input and output parameters. During a numerical experiment, it was found that for a train speed of 100 km/h, the required excess pressure is 560 kPa, and the most energy-efficient way to increase pressure is to regulate the area of the outlet valves. [ABSTRACT FROM AUTHOR]

Introduction. Railway transport has ultrasonic control as one of the main methods of detection of defects of the type of continuity violation (cracks, pores and others) both in the base metal and in weld seams of various items. Ultrasonic control tools primarily include a flaw detector with piezoelectric transducers. Piezoelectric transducers are usually supplied with the flaw detector depending on the general or specialized configuration. Flaw detector manufacturers often offer the customer their own piezoelectric transducer kits for certain device configurations with installed software referring to incompatibility of other manufacturers piezoelectric transducers with the electronic unit. The article is intended to carry out a comparative analysis of ultrasonic control sensitivity using straight and angle transducers of different manufacturers, and to compare the results with the control sensitivity using piezoelectric transducers traditionally used on the railways.Materials and methods. The paper gives the results of testing the sample using Flaw Detector UD2-102 Peleng produced by Altek LLC. Industrial oil I-20 was used as a contact fluid. The authors compared the following piezoelectric transducers: straight (made by Altek LLC and NPO INAKON (Russia)) and angle (Altek LLC (Russia), Iskatel-2 LLC (Russia) and SIUI (China)).Results. The paper reports the results of an experiment detecting artificial reflectors in the form of through cylindrical side holes in a sample of 20GL steel by straight and angle piezoelectric transducers of different manufacturers using Flaw Detector UD2-102 Peleng.Discussion and conclusion. Connection of other manufacturers transducers to Flaw Detector UD2-102 Peleng of Altek LLC confirmed that they are compatible with the electronic unit. Thus, given the choice of a wide selection of piezoelectric converters from various manufacturers, the requirement of coordination with the electronic unit of Flaw Detector UD2-102 may be neglected. At the same time, it is important that the manufacturer stipulates the joint use of its product with other types of flaw detectors.

Introduction. Interference in the continuous automatic cab signalling channel distorts transmitted signals and causes signalling malfunctions. Reduction of interference in the channel involved a previously proposed receiver with quadrature channels and its implementations with non-linear signal transformation in one or two sections of the receiver. The research is intended to find the best implementations of the quadrature receiver.Materials and methods. The research uses a computer simulation of the operation of the studied receivers under the influence of harmonic interference from a power line. For this purpose, the authors used Simulink visual programming environment and developed receiver simulations, applied the harmonic interference simulation model and conducted experiments to assess noise immunity expressed as a time interval showing receiver malfunction.Results. The researchers determined the effect of non-linear signal transformation on the harmonic noise immunity of the receivers.Discussion and conclusion. The research shows that the receiver with a deadband is the most preferable of all considered variants of quadrature receivers in terms of maximum harmonic noise immunity. The receiver with combined interference suppressor and deadband is slightly inferior.

DC railway electrification was deployed at the beginning of the 20th century in several countries in Europe. Today, this power system is no longer adapted to the demands of increased rail traffic. Due to the relatively low voltage level, the current consumed by the trains reaches several kAs. So, in the worst case, the locomotives cannot operate at their rated power due to the voltage drop along the contact line. Conventional solutions to reduce the voltage drop consist of increasing the cross-section of overhead lines or reducing the length of sectors by installing additional substations. Nevertheless, these solutions are expensive and not always feasible. The implementation of a Modular Battery Energy Storage System (MBESS) can be an alternative solution to reinforce the railway power supply. This paper first presents an MBESS based on elementary blocks associating Full-SiC Isolated DC-DC converter and battery racks. The electrical models of a railway sector and an elementary block are described, and simulations are performed considering real railroad traffic on two sectors of the French National Rail Network, electrified at 1.5 kV. The results show that the installation of an MBESS in the railway sector boosts the locomotive's voltage while also increasing overall system efficiency. [ABSTRACT FROM AUTHOR]

Trains are a very important mode of transportation for freight and passengers in Indonesia. This encourages PT KAI, which is a train operator in Indonesia, to improve its performance. Currently PT KAI uses several types of locomotives. CC201 locomotives made in 1977-1978 and CC203 made in 1995 are locomotives that are still widely operated. Fuel consumption is one of the components of train operating costs, the percentage of which reaches more than 30%. Railroad fuel consumption is strongly influenced by various factors, one of which is the aerodynamic performance of the locomotive. This study presents an evaluation of the aerodynamic performance of CC201 and CC203 locomotives. The research stages include direct measurement of locomotive geometry and dimensions, CAD drawing creation using SoildWorks and aerodynamic evaluation using ANSYS software. The simulation results show that the flat front design of the CC201 locomotive has greater aerodynamic resistance. This can be seen from the pressure contours and turbulence around the locomotive body. This causes the drag force of the CC201 locomotive to be 44% greater than that of the CC203 locomotive. [ABSTRACT FROM AUTHOR]

To study the problems related to two-stage degradation characteristics of locomotive wheels, a two-stage Wiener process-based method for predicting the remaining service life was proposed. The wheel rim degradation model was established by using a two-stage Wiener process model, and the individual differences in the wheel degradation process were characterized by the random drift coefficient. The expectation maximum (EM) algorithm and Bayesian theory were used to achieve offline parameter estimation and online updating of the degradation model parameters. The change point in the wheel degradation process was determined and found via the Schwarz information criterion (SIC). Finally, an example of wheel rim degradation data from a certain locomotive was used for validation. The results show that, compared with the single-stage degradation model, the two-stage degradation model considering the change point is more in line with the field reality, and the prediction accuracy at 80% of the life quantile of the wheel is improved by 9.42%. The prediction of the remaining service life can provide a certain theoretical basis for the optimization of the wheel turning cycle. [ABSTRACT FROM AUTHOR]

The autonomous control of landing procedures can provide the efficiency and precision that are vital for the successful, safe completion of space operations missions. Controlling a lander with this precision is challenging because the propellants, which will be expended during the operations, represent a significant fraction of the lander's mass. The mass variation of each tank profoundly influences the inertia and mass characteristics as thrust is generated and complicates the precise control of the lander state. This factor is a crucial consideration in our research and methodology. The dynamics model for our lander was developed where the mass, inertia, and center of mass (COM) vary with time. A feed-forward neural network (NN) is incorporated into the dynamics to capture the time-varying inertia tensor and COM. Moreover, the propellant takes time to travel through the feed lines from the storage tanks to the engine; also, the solenoid valves require time to open and close. Therefore, there are time delays between the actuator and the engine response. To take into account these sources of variations, a combined time delay is also included in the control loop to evaluate the effect of delays by fluid and mechanisms on the performance of the controller. The time delay is estimated numerically by a Computational Fluid Dynamics (CFD) model. As part of the lander's control mechanism, a thrust vector control (TVC) with two rotational gimbals and a reaction control system (RCS) are incorporated into the dynamics. Simple proportional, integral, and derivative (PID) controllers are designed to control the thrust, the gimbal angles of the TVC, and the torque required by the RCS to manipulate the lander's rotation and altitude. A complex mission with several numerical examples is presented to verify the hover and rotational motion control. [ABSTRACT FROM AUTHOR]

Robotic lower-limb prostheses, with their actively powered joints, may significantly improve amputee users' mobility and enable them to obtain healthy-like gait in various modes of locomotion in daily life. However, timely recognition of the amputee users' locomotive mode and mode transition still remains a major challenge in robotic lower-limb prosthesis control. In the paper, the authors present a new multi-dimensional dynamic time warping (mDTW)- based intent recognizer to provide high-accuracy recognition of the locomotion mode/mode transition sufficiently early in the swing phase, such that the prosthesis'joint-level motion controller can operate in the correct locomotive mode and assist the user to complete the desired (and often power-demanding) motion in the stance phase. To support the intent recognizer development, the authors conducted a multi-modal gait data collection study to obtain the related sensor signal data in various modes of locomotion. The collected data were then segmented into individual cycles, generating the templates used in the mDTW classifier. Considering the large number of sensor signals available, we conducted feature selection to identify the most useful sensor signals as the input to the mDTW classifier. We also augmented the standard mDTW algorithm with a voting mechanism to make full use of the data generated from the multiple subjects. To validate the proposed intent recognizer, we characterized its performance using the data cumulated at different percentages of progression into the gait cycle (starting from the beginning of the swing phase). It was shown that the mDTW classifier was able to recognize three locomotive mode/mode transitions (walking, walking to stair climbing, and walking to stair descending) with 99.08% accuracy at 30% progression into the gait cycle, well before the stance phase starts. With its high performance, low computational load, and easy personalization (through individual template generation), the proposed mDTW intent recognizer may become a highly useful building block of a prosthesis control system to facilitate the robotic prostheses' real-world use among lower-limb amputees. [ABSTRACT FROM AUTHOR]

Anomaly detection in the industrial context, identifying defective products and their categorization, is a prevalent task. It is aimed to acknowledge if training and testing multilabel classification models on textures to deploy on an MCU is possible. The focus is deploying lightweight models on MCUs, performing a multilabel classification on textures for industrial usage. For this purpose, a Systematic Literature Review was conducted, which allows knowing the commonly used machine learning models in industrial products anomaly detection and what methods are used to defect detection on textures. Through the Systematic Literature Review, was possible to understand the range of different and combined methods, the methods used in multilabel classification, the most common hyper-parametrizations and popular inferences engines to train machine-learning models to deploy on MCUs, and some techniques applied to overcome the restricted resources of memory and inference time associated with MCUs. [ABSTRACT FROM AUTHOR]

This research investigates the imperative issue of fuel consumption and emissions in diesel locomotives during idle states, with a particular focus on the deployment of Auxiliary Power Units (APUs) in the neutral position (R-H). Diesel locomotives often exhibit a substantial fuel consumption rate, ranging from 23 to 25 litres per hour, during idling. This paper aims to elucidate the intricacies of optimising fuel consumption while concurrently addressing emission concerns without disrupting essential locomotive functions. In the quest for improved fuel efficiency and reduced emissions in locomotive operations, the utilisation of APUs in the neutral position (R-H) emerges as a pivotal point of investigation. APUs, which are auxiliary engines connected to the primary locomotive engine, play a significant role in achieving these objectives. The study delves into the health status and functionality of APUs during the locomotive's neutral state, examining their impact on fuel consumption and emissions. A comprehensive understanding of this aspect is crucial for developing effective strategies to enhance locomotive performance while curbing environmental impact. It is crucial to recognise that locomotives serve essential functions even when idling, such as supplying compressed air to maintain brake pipe integrity, powering the locomotive control system, and ensuring the charging of batteries. Consequently, locomotive operators often refrain from shutting down the primary diesel engine to conserve fuel. This research, through a meticulous analysis of APUs in the neutral position, endeavours to strike a balance between fuel conservation and the preservation of critical locomotive functions. By exploring the intricacies of APU utilisation, this study contributes to the ongoing efforts aimed at achieving sustainability and improved fuel economy within the railway industry. [ABSTRACT FROM AUTHOR]