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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.