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Mobile British artisans played a key role in the global diffusion of industrialization, taking their skills to Continental Europe and the USA. While research in recent decades among those who might be classed as minor innovators or tweakers has increased our knowledge and understanding of their contribution to this process, less is known about those skilled tradespeople who might be classed as implementers, in other words, those who proved capable of constructing, installing and operating new industrial plant and machinery but are not noted for their innovations. This article is the study of the life and context of William Harman, a highly mobile individual involved in the construction of steamships and locomotives and whose career took him from his home near Hull to France and across the United States as the frontier moved westwards. [ABSTRACT FROM AUTHOR]

The bogie is a critical component of high-velocity trains. As train velocity rises, the operational quality is increasingly influenced by aerodynamic forces. The aerodynamic characteristics of bogies significantly impact the safety of train operations. This article examines a real high-velocity train model, constructing a 3-group train model, and developing a mathematical model of high-velocity train operation on open lines. Using three-dimensional steady-state Navier–Stokes equations, the flow field characteristics, pressure spread, aerodynamic forces, and torque characteristics on the bogie and body of high-velocity locomotives operating at velocities of 200 km/h, 250 km/h, 300 km/h, and 350 km/h are calculated, with measurement spots set to study the trend of pressure variation with train velocity. The research findings indicate that pressure at the same location on the body surface rises with vehicle velocity, with a quadratic link between the two. The uneven pressure spread between two bogies of the same vehicle and between two axles of the same bogie indicates that aerodynamic forces can cause axle load transfer in high-velocity trains. The highest values of aerodynamic resistance and lift happen at the front bogie, and the resistance and lift of both a single carriage and the entire vehicle increase with velocity, following a quadratic relationship. The highest nodding torque of the train body occurs on one vehicle, while the highest nodding torque of the bogie occurs on the 6th bogie, with both torques increasing with velocity, also in a quadratic relationship. [ABSTRACT FROM AUTHOR]

Background: Understanding the gait pattern of patients eligible for total hip arthroplasty (THA) due to hip osteoarthritis (OA) offers valuable information for improving locomotive syndrome (LS). This study aims to measure the gait patterns of THA-eligible patients using an optical motion capture system and to analyze these patterns using principal component analysis (PCA). Additionally, this study examines the relationship between THA-induced gait patterns and LS. Methods: This before-after study included 237 patients who underwent unilateral primary THA due to hip OA. The primary outcome measures were spatiotemporal gait parameters. Secondary outcome measures included three LS risk tests: a stand-up test, a two-step test, a 25-question Geriatric Locomotive Function Scale (GLFS-25), and total clinical decision limits stages. PCA was performed using 16 spatiotemporal gait parameters collected before and three months after THA. Principal components (PC) were selected to achieve a cumulative contribution rate of 90% (0.9) or higher. Each summarized PC was compared using a paired t-test before and three months after THA. Furthermore, multiple regression analysis was conducted to determine how changes in each PC between before and three months after THA related to changes in the four LS evaluation items. Results: PCA identified three principal components (PC1, PC2, PC3) that accounted for a cumulative contribution rate of 0.910 using 16 spatiotemporal gait parameters. When comparing before and three months after THA for all three PCs, significant differences were observed in each PC (p < 0.001), with overall walking ability and stance phase being higher three months after THA than before THA, while the asymmetry of support time was lower three months after THA. The results of multiple regression analysis revealed that PC1, PC2, and PC3 were the most influential factors in total clinical decision limits stage. For each LS risk test, the factors related to the stand-up test were identified as PC1, PC2, and PC3, while the factors related to the two-step test were identified as PC1 and PC2. The factors related to the GLFS-25 were also identified as PC1 and PC2. Conclusions: The most important findings of this study indicate that the three PCs represent over 90% of the 16 spatiotemporal gait parameters, which are associated with total clinical decision limits stage and LS risk tests. The present results suggest that PC1 represents overall walking ability, PC2 represents the stance phase, and PC3 represents asymmetry of support time. Gait pattern characteristics, such as overall walking ability, stance phase, and asymmetry of support time, were clearly defined by these PCs. Regarding the relationship between PC and LS, all three PCs are related to total clinical decision limits stage. In addition, PC1 and PC2 related to all three LS risk tests, and PC3 related only to the stand-up test. [ABSTRACT FROM AUTHOR]

In the context of locomotive traction systems, the power electronic traction transformer (PETT) represents a pivotal component, fulfilling essential functions pertaining to electrical isolation and power control. The majority of existing PETT prototypes employ a combination of a cascade structure and an ISOP structure. The aforementioned scheme effectively reduces the voltage withstand level of the power devices on the input side, yet it also necessitates the utilisation of a greater number of power devices and passive components within the PETT. In order to further reduce the number of power devices used, this paper proposes a new cascaded PETT design. The proposed PETT will adopt a scheme combining a cascade structure and a hardware circuit multiplexing. This paper first analyses the operation principle of the new circuit under non-single frequency PWM control. It then derives the design equations for some hardware parameters and control circuits. Finally, it verifies the effectiveness of the proposed PETT through simulation analysis. [ABSTRACT FROM AUTHOR]

Introduction. The paper considers equipping rolling stock with new lightweight wheel stops of increased reliability, as well as the use of the drag shoes on space intervals, including abnormal situations.Materials and methods. The authors performed field tests to compare the performance of lightweight wheel stops TM 37.10.2016 and hump drag shoes 8739.00. The paper determined the tractive force for moving a empty car train and loaded car train equipped with drag shoes.Results. The paper analyses the securing of railway rolling stock with wheel stops on space intervals with different gradients and different weights of trailing rolling stock. The paper describes the developed methodology of emergency withdrawal of a multiple unit rolling stock with a wedged wheel pair using wheel stops and determines the ultimate sliding distance of the wedged wheel pair compared to the hump drag shoes. The paper established that withdrawing the electric rolling stock from the space interval with the wedged wheel pair requires 4 times more wheel stops than the hump drag shoes.Discussion and conclusion. The authors shown that traction rolling stock permits the practical replacement of hump drag shoes 8739.00 currently in use with wheel stops TM 37.10.2016. The braking characteristics of wheel stops and hump drag shoes only differ during the short initial period of paint abrasion on the rubbing surface of the wheel stop skids. Since the drag shoes for rolling stock are intended for emergency, their rubbing surface must not be painted.

To measure the effectiveness of learning activities, intensive research works have focused on the process of competency building through the identification of learning stages as well as the setup of related key performance indictors to measure the attainment of specific learning objectives. To organize the learning activities as per the background and skills of each learner, individual learning styles have been identified and measured by several researchers. Despite their importance in personalizing the learning activities, these styles are difficult to implement for large groups of learners. They have also been rarely correlated with each specific learning stage. New approaches are, therefore, needed to intelligently coordinate all the learning activities while self-adapting to the ongoing progress of learning as well as to the specific requirements and backgrounds of learners. To address these issues, we propose in this paper a new framework for an intelligent management of the competency building process during learning. Our framework is based on a recursive spiral Assess-Predict-Oversee-Transit model that is orchestrated by a multi-agent system. This system is particularly responsible of enabling smart transitions between learning stages. It is also responsible of assessing and predicting the process of competency building of the learner and, then, making the right decisions about the learning progress, accordingly. Results of our solution were demonstrated via an Augmented Reality app that we created using the Unity3D engine to train learners on Air Conditioner maintenance. [ABSTRACT FROM AUTHOR]

This study addresses the issue of carbody hunting in an electric locomotive induced by low wheel-rail contact conicity. The main objective is to mitigate this unstable motion by optimising the location of yaw dampers while ensuring bogie stability under high conicity conditions. A field test was first conducted to observe the carbody hunting behaviour, and a detailed locomotive dynamics model was then developed and validated using experimental data. The impact of yaw damper locations on locomotive stability was investigated, taking into consideration different carbody modes. The findings reveal the mechanism behind the deterioration of carbody stability due to the yaw damper installation angle and two installation layouts were proposed to enhance the carbody stability. Comparisons were then made with traditional solutions using both linear and nonlinear analysis, and experimental validation confirmed the effectiveness of the optimised yaw damper locations in improving carbody stability. This research highlights the importance of optimising the yaw damper's location to suppress carbody hunting, providing valuable insights for railway engineers and offering a promising solution for enhancing stability in high-speed train. [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.)

The problem of modelling and simulating traditional crafting actions is addressed, motivated by the goals of craft understanding, documentation, and training. First, the physical entities involved in crafting actions are identified, physically, and semantically characterised, including causing entities, conditions, properties, and objects, as well as the space and time in which they occur. Actions are semantically classified into a taxonomy of four classes according to their goals, which are shown to exhibit similarities in their operation principles and utilised tools. This classification is employed to simplify the create archetypal simulators, based on the Finite Element Method, by developing archetypal simulators for each class and specialising them in craft-specific actions. The approach is validated by specialising the proposed archetypes into indicative craft actions and predicting their results in simulation. The simulated actions are rendered in 3D to create visual demonstrations and can be integrated into game engines for training applications. [ABSTRACT FROM AUTHOR]

Copyright of Railway Construction Technology is the property of Railway Construction Technology 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.)

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]

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 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]

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]

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]

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.

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]

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]

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]

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]

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]

To investigate the harmonic characteristics of electric locomotives connected to a photovoltaic (PV) power grid based on the actual parameters of a region in Tibet, this paper establishes a simulation model of an electric power grid, including PV and electric locomotive. First, theoretical analysis is conducted to study the harmonic characteristics of electric locomotives and PV power stations. On this basis, we built the MATLAB model to analyze the influence of dynamic working conditions on the locomotive and PV sides on the harmonic characteristics of the power grid. Through the first, second, and third working conditions, a simulation analysis is performed to examine the harmonic characteristics of an electric locomotive when connected to the grid, which includes a PV power source. The results show that the grid side current, including PV and electric locomotive, has a three-phase equilibrium phenomenon, and at the same time, the grid side current harmonic characteristics, including PV and electric locomotive, are mainly reflected in the 17, 19, 21, 23, and 25 frequency odd harmonics. [ABSTRACT FROM AUTHOR]

The proper representation of friction contact conditions between each wheel and the rail is necessary to accurately model the behaviour of a heavy haul locomotive since friction conditions at the wheel-rail interface affect the locomotive's dynamic performance under traction and braking conditions. In normal operations, a phenomenon commonly known as rail cleaning effect occurs. The rail cleaning effect causes increased friction coefficients between the following wheel treads and the rail head. The wheel-rail interaction causes the third body layer to be partly or wholly eliminated from the surfaces in contact and generates new layer. An experimental analysis of the changes in friction coefficients under simulated locomotive wheel-rail contact conditions, in terms of contact pressure and slip, is presented in this paper. For this study, data processing equations are presented to obtain the experimental traction coefficient and slip. Furthermore, the rail cleaning effect is examined under different slip conditions. The experiment shows the traction coefficient increases for a given number of cycles until reaching a steady value, demonstrating that the rail cleaning effect is measurable in various slip conditions on a twin disc machine. [ABSTRACT FROM AUTHOR]

The use of dual-drive rolling stock is a relatively new solution in the railway market. Vehicles with such type of powertrain are more versatile because it combines the advantages of using diesel vehicles and electric vehicles that consume energy from overhead electric traction. The concept of using such vehicles is highly innovative and has many advantages. However, the design and construction process is more complicated and requires more work than in the case of conventional systems. This article presents the methodology and process of selecting an engine-generator set for a dual-drive locomotive. Indicators and procedures crucial in the process of selecting a dual-drive system for a locomotive, were described and evaluated. All the above mentioned in the work were used during the real design process of a fully Polish locomotive with both diesel and electric drives. The locomotive in Diesel mode was to have an output power of circa 1560 kW for cargo transport. Calculations for the locomotive's power balance are included, showing power losses in the system and for locomotive's own needs. It has been shown that in cargo transport 77% of the maximum engine power is used as tractive power, and in passenger transport 58.6%. [ABSTRACT FROM AUTHOR]

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Understanding the unstable evolution of railway slopes is the premise for preventing slope failure and ensuring the safe operation of trains. However, as two major factors affecting the stability of railway slopes, few scholars have explored the unstable evolution of railway slopes under the joint action of rainfall-vibration. Based on the model test of sandy soil slope, the unstable evolution process of slope under locomotive vibration, rainfall, and rainfall-vibration joint action conditions was simulated in this paper. By comparing and analyzing the variation trends of soil pressure and water content of slope under these conditions, the change laws of pore pressure under the influence of vibration and rainfall were explored. The main control factors affecting the stability of slope structure under the joint action conditions were further defined. Combined with the slope failure phenomena under these three conditions, the causes of slope instability resulting from each leading factor were clarified. Finally, according to the above conclusions, the unstable evolution of the slope under the rainfall-vibration joint action was determined. The test results show that the unstable evolution process of sandy soil slope, under the rainfall-vibration joint action, can be divided into: rainfall erosion cracking, vibration promotion penetrating, and slope instability sliding three stages. In the process of slope unstable evolution, rainfall and vibration play the roles of inducing and promoting slide respectively. In addition, the deep cracks, which are the premise for the formation of the sliding surface, and the violent irregular fluctuation of soil pressure, which reflects the near penetration of the sliding surface, constitute the instability characteristics of the railway slope together. This paper reveals the unstable evolution of sandy soil slopes under the joint action of rainfall-vibration, hoping to provide the theoretical basis for the early warning and prevention technology of railway slopes. [ABSTRACT FROM AUTHOR]

During the COVID-19 pandemic, this study investigated the potential of exercise habits to improve quality of life (QOL) and prevent locomotive syndrome (LS) in residents of Yakumo-cho, Hokkaido, Japan. Participants from the 2018 health checkup were surveyed in February 2022, focusing on 200 respondents. These individuals were divided based on their 2018 exercise habits (at least 1 h per week): the exercise group (E group) and the non-exercise group (N group), further categorized in 2022 into the 2022E and 2022N groups. QOL was measured using the SF-36 (physical functioning, general health, physical role, physical pain, vitality, social functioning, emotional role, and mental health) and EuroQoL 5-dimension 5-level questionnaires (mobility, self-care, usual activities, pain/discomfort, and anxiety/depression), and LS was assessed with the 25-question geriatric locomotive function scale. These showed no significant change in exercise habits from 2018 to 2022. In the non-LS group, the 2022E group had higher vitality and emotional role functioning scores compared to the 2022N group. For those with LS, the 2022E group reported less physical pain. Notably, the LS incidence was significantly lower in the 2022E group. This study concludes that consistent exercise habits positively impact QOL and reduce the LS risk, underscoring the importance of regular physical activity, especially during challenging times like a pandemic. These findings highlight the broader benefits of maintaining exercise routines for public health, particularly in periods of global health crises. Based on our findings, we recommend that people continue to exercise at least one hour per week to prevent LS. [ABSTRACT FROM AUTHOR]

Multibody simulations are widely used for the dynamic analysis of railway vehicles, including the acceptance of vehicle running behaviour. Among these, the freight vehicles have, generally, friction damped suspensions for which numerical modelling is particularly challenging due to the contacting geometries, the intermittent contact, and the frequent stick-slip transitions. The impact of modelling decisions of friction-damped suspensions on the acceptance quantities for vehicle behaviour is the focus of this work. The selection of friction models and tuning of their parameters is challenging. In particular, the selection of friction coefficients is not straight forward, as friction conditions vary during operation and over time. This work aims to address both problems. A model of a friction-damped freight locomotive is used to simulate the dynamic response of the vehicle under realistic operation conditions and assess the impact of the friction modelling decisions. The results show that the use of different friction models provides similar results if the parameters are appropriately tuned. In contrast, the selection of friction coefficients significantly impacts the acceptance quantities, with emphasis on the wheel-rail forces at small radius curve transitions. The results recommend that the standard should include variations of the friction coefficients used for the friction-damped suspensions. [ABSTRACT FROM AUTHOR]

The risk factors for progression of severity of locomotive syndrome (LS) remain unclear. We conducted a longitudinal observational study of 1148 community-dwelling residents (median age, 68.0 years old; 548 males, 600 females) from 2016 to 2018. LS was assessed by the 25-question Geriatric Locomotive Function Scale (GLFS-25), and total scores of ≤6 points, 7–15 points, 16–23 points, and ≥24 points were diagnosed as non-LS, LS-1, LS-2, and LS-3, respectively. If the LS severity in 2018 was higher than in 2016, the case was defined as progression of LS severity; otherwise, it was defined as non-progressive LS. We compared the age, gender, body mass index, smoking status, alcohol consumption, living situation, car use, chronic musculoskeletal pain, comorbidities, metabolic syndrome, physical activity, and LS severity in 2016 between the progression and non-progression groups. Furthermore, a multivariate logistic regression analysis was performed to elucidate the risk factors for progression of LS severity. Participants in the progression group had a significantly older age, a lower rate of car use, a higher rate of low back pain, a higher rate of hip pain, a higher rate of knee pain, a higher GLFS-25 total score, and a higher rate of LS-2 than those in the non-progression group. The multivariate logistic regression analysis revealed that older age, female gender, higher body mass index (≥25.0 kg/m2), presence of low back pain, and presence of hip pain were risk factors for the progression of LS within two years. To prevent the progression of LS severity, related prophylaxis strategies should be implemented, especially for individuals with the above-mentioned characteristics. Further longitudinal studies with a longer observation period are necessary. [ABSTRACT FROM AUTHOR]

If there are trains with the same train number in the CTC system, the wireless route notice may be sent to a wrong train, which will cause confusion to the driver. To solve this problem, this paper proposes a solution to improve the wireless route notice transmission by the CTC system in GSM-R network covered sections. The proposed solution obtains the locomotive or EMU operation plan from the locomotive or EMU dispatching system through the CTC system. Then, it determines the leading locomotive's locomotive number or the EMU's train set number after matching with the actually received wireless train number information, to ensure that the CTC system sends the wireless route notice to the correct train. Thus, it can effectively prevent the incorrect transmission of wireless route notice by the CTC system without changing the wireless route notice transmission logic in the CTC system. [ABSTRACT FROM AUTHOR]

This article analyzes the relationship between Holocaust trauma and firsthand poetic testimonies through the lens of literary acoustics. Specifically, it explores the work of three Jewish poets, Stanisław Wygodzki, Ilona Karmel, and Stanisław Jerzy Lec, who wrote in Polish of their tragic experiences in the Nazi camps. The article compares these poetical works to involuntary flashbacks composed of haunting sounds that recall trauma and violence and applies the concept of thantosonics to these auditory memories. In particular, the author notes the importance of trains as not only an auditory motif, but also as the metrical underpinning of the verses, and as a point of juxtaposition against sounds of innocence in the Holocaust soundscape. Furthermore, the article also explores the imagery of folk dance as a kind of danse macabre , as well as instances of involuntary sonic identification with the perpetrators. [ABSTRACT FROM AUTHOR]

A clean solar hydrail, a locomotive operated by solar and hydrogen energy, has received significant attention as an alternative to a current fossil fuel-based locomotive. Nevertheless, the feasibility test of solar hydrail is still challenging since it has not yet been practically developed. Herein, we employed digital twin technology to design and operate solar hydrail and diesel locomotive. 30 years of operation simulation starting from 2021 was conducted based on the data of Gangwon-do, South Korea. It was confirmed that replacing the single diesel locomotive with solar hydrail can provide about 59 % lower net present cost and annual harmful emission reduction of approximately 300 tons. Sensitivity analyses were also conducted to mitigate future uncertainty, and the solar hydrail was a better option than the diesel locomotive in every scenario. This study demonstrates that solar hydrail is the successful substitute for the diesel locomotive currently operated in South Korea. • 30 years of operation was simulated for solar hydrail and diesel locomotive. • Solar hydrail can have $2,026,279 lower NPC than diesel locomotive. • Solar hydrail yearly saves about 300 tons of emissions compared to diesel locomotive. [ABSTRACT FROM AUTHOR]

This is a communication from a case study of twelve Brazilian freight transportation railroads showing the feasibility of hydrogen-powered locomotives over diesel-powered locomotives. Load increase models are made up to 2035 to project the performance of locomotives and their impacts on these railroads. Eight types of diesel locomotives were chosen for comparison. Interesting finding is that higher specific consumption has lower capacity to haul a heavier load per unit of locomotive power. Trend lines found indicate a reduction of 48% in energy demand if hydrogen is adopted. Results suggest environmental gains, with a reduction in total emissions of 132 kt CO 2 /year by 2035. A variable was created ("Hydrogen Specific Consumption 4k – HSC4k"), which shows the consumption of hydrogen as a function of the distance of the section traveled and the power of the locomotive employed. The methodology proposed is replicable to any rail environment if the indicated data is available. [Display omitted] • 12 stretches and eight types of diesel-powered locomotives served as base comparison. • Energy demand in railways can be reduced up to 48% in 2035 if hydrogen is employed. • Mitigation of 132 ktCO 2 /year is possible if locomotive diesel is switched by hydrogen. • A maximum of 62 tkm/MJ for energy efficiency in the rail freight can be observed. • Hydrogen Specific Consumption – 4k variable was discovered and successfully applied. [ABSTRACT FROM AUTHOR]

At present, the research on crashworthiness of locomotive mainly adopts the method of theoretical analysis, numerical simulation and component test, it is too expensive and less repeatable to carry out vehicle crash tests. Therefore, a method to construct the collision equivalent scaled model (SM) for locomotive based on multi-parameter nondimensional is presented in this paper. Firstly, an equivalent method of structural dynamic responses was proposed. The extraction process and analysis method of dynamic responses for thin plate structures widely existing in locomotives were studied. Then, according to the structural characteristics of the locomotive, the partition equivalent design was carried out, and a dimensionless analysis model of impact dynamic responses for SM was established. Finally, the SM crash test was carried out to verify the effectiveness of collision equivalent SM established, it was found that the SM has high reliability, it can achieve equivalence with the locomotive for energy absorption, average impact force, average acceleration of cab and center of gravity of vehicle body. Carrying out the SM crash test can study the reasonable configuration of energy absorption parameters for locomotives and obtain the impact dynamic responses of locomotives under different configurations of energy absorption parameters. [ABSTRACT FROM AUTHOR]

Precooling technology is a widely used method for increasing the flight speed of turbojet engines. To solve the problems of oversized fuel tank and engine performance degradation caused by the low density of hydrogen fuel, a new precooled engine cycle based on hydrogen production technology from ammonia cracking is proposed. To evaluate the engine performances, a thermodynamic model and a test platform are established. The study shows that the test heat sink of ammonia is 4.12 MJ at 620.5 °C, and the upper boundaries of heat sink and hydrogen production rate of ammonia are higher than other chemical fuels. Besides, the optimized fuel ratio is set to 2.0, and the best compressor pressure ratio could be obtained at the point with the highest engine performances Further, the maximum flight Mach number of precooled engine is Ma 4.69, and compared with GE90 and J-58 engines, the carbon emission of precooled engine could be reduced by 94.15% and 72.95% respectively. Moreover, by increasing the cold storage degree, the engine performance can be further improved especially at high pressure ratio. Overall, the research of this paper is hopeful to provide a new idea and necessary theoretical support for the development of high-performance supersonic aero-engine. • A new precooled engine cycle based on hydrogen production technology is proposed. • The test heat sink of ammonia reaches 4.12 MJ at 620.5 °C. • The maximum flight Mach number of precooled engine is Ma 4.69. • The carbon emission of precooled engine could be reduced by 94.15%. • The method to improve the engine performances through clod storage is also proposed. [ABSTRACT FROM AUTHOR]

Root gap of fillet welds can not be fully controlled in a real welding scenario, while engineers in the industry must provide reasonable maintenance solutions for gaps with different size. Following standard working loads of the International Union of Railways, influences of the dimensions of root gap on the maximum stress amplitude (AMAX) in fillet weld were analyzed. It is found that: 1) The position of the maximum AMAX value calculated based on the standard working conditions coincides with the position of actual fatigue crack; 2) Fillet welds with root gaps of typical size have more than double the AMAX values of fillet welds without root gaps; 3) By using Goodman fatigue limit diagram, the specific disposal scheme of root gap with varying dimensions was determined. These results have a general guiding significance for improving the fatigue properties of structures containing fillet welds. [ABSTRACT FROM AUTHOR]

Locomotive syndrome is closely related to the state of long-term care. This study aimed to longitudinally evaluate long-term care certification occurrence in locomotive syndrome using data from the Miyagawa study. The study included 470 individuals (168 males, 302 females; mean age, 70.7 years) with no long-term care certification at the time of participation in the study. Locomotive syndrome was classified into three stages (stages 1–3) according to the 25-question Geriatric Locomotive Function Scale. Analysis was performed with long-term care certification occurrence as the endpoint and locomotive syndrome stage as the explanatory variable. The median observation period was 6.3 years, and long-term care certification occurred in 69 (34.2%) and 30 (11.2%) of the participants in the locomotive syndrome and no-locomotive syndrome groups, respectively. Independent risk factors of long-term care certification occurrence were locomotive syndrome stage-3 (hazard ratio: 2.27) in the total number of studies, and locomotive syndrome stages 2 (hazard ratio: 2.49) and 3 (hazard ratio: 2.79) in females. Locomotive syndrome stage-3 was an independent risk factor in long-term care certification occurrence due to musculoskeletal disorders (hazard ratio: 3.89). The higher the locomotive syndrome stage, especially in females, the higher the risk of long-term care certification occurrence. [ABSTRACT FROM AUTHOR]