Miracle-dz/UniFAR-FTUs huggingface dataset:
Position, Force and Stiffness Control of a Stewart-Platform-Type Ankle-Foot Assist Device

In this research, we developed an ankle-foot assist device for foot rehabilitation and walking assistant purpose. In order to support all 6 DOFs human foot motion (the rotations of human foot and the displacement of rotation axes), a six air cylinders drive Stewart Platform Mechanism was used. In our previous work, we have proposed a measuring and calculating method to get the posture of human foot and estimate the instantaneous rotation axis of ankle joint [1]. In this paper, we further propose a new method to control the position, force and stiffness of this device. The position can be controlled even if the potentiometers do not measure the length of air cylinders directly. The force can be controlled by changing the air pressures in two chambers of each cylinder, without using any force sensors. The stiffness can also be controlled which is controlled by changing the stiffness of all cylinders, by changing the pressures in chambers. These control methods are tested in experiments for one cylinder and for developed assist device. The results show the accuracy and validity of the device and the method in the control of position, force and stiffness.Copyright © 2012 by ASME
Guidance for Implementing Video Consultations in Danish General Practice: Rapid Cycle Coproduction Study

Background The COVID-19 pandemic has changed various spheres of health care. General practitioners (GPs) have widely replaced face-to-face consultations with telephone or video consultations (VCs) to reduce the risk of COVID-19 transmission. Using VCs for health service delivery is an entirely new way of practicing for many GPs. However, this transition process has largely been conducted with no formal guidelines, which may have caused implementation barriers. This study presents a rapid cycle coproduction approach for developing a guide to assist VC implementation in general practice. Objective The aim of this paper is to describe the developmental phases of the VC guide to assist general practices in implementing VCs and summarize the evaluation made by general practice users. Methods The development of a guide for VC in general practice was structured as a stepped process based on the coproduction and prototyping processes. We used an iterative framework based on rapid qualitative analyses and interdisciplinary collaborations. Thus, the guide was developed in small, repeated cycles of development, implementation, evaluation, and adaptation, with a continuous exchange between research and practice. The data collection process was structured in 3 main phases. First, we conducted a literature review, recorded observations, and held informal and semistructured interviews. Second, we facilitated coproduction with stakeholders through 4 workshops with GPs, a group interview with patient representatives, and individual revisions by GPs. Third, nationwide testing was conducted in 5 general practice clinics and was followed by an evaluation of the guide through interviews with GPs. Results A rapid cycle coproduction approach was used to explore the needs of general practice in connection with the implementation of VC and to develop useful, relevant, and easily understandable guiding materials. Our findings suggest that a guide for VCs should include advice and recommendations regarding the organization of VCs, the technical setup, the appropriate target groups, patients’ use of VCs, the performance of VCs, and the arrangements for booking a VC. Conclusions The combination of coproduction, prototyping, small iterations, and rapid data analysis is a suitable approach when contextually rich, hands-on guide materials are urgently needed. Moreover, this method could provide an efficient way of developing relevant guide materials for general practice to aid the implementation of new technology beyond the pandemic period.
Substrate integrated waveguide filter with mixed coupled modified trisections

A novel multilayer substrate integrated waveguide (SIW) filter with an improved stopband using mixed coupled modified trisections (MCMTs) is presented. The proposed filter is composed of two cascade MCMTs embedded in LTCC substrate. Four transmission zeros (TZs) can be generated with only three resonators, where two TZs near the passband are utilised to achieve sharper skirt selectivity, and another two TZs for the upper wide stopand. A 10 GHz experimental filter has been designed, fabricated and measured to validate the proposed method.
Adaptive voltage droop scheme for voltage source converters in an islanded multibus microgrid

In this study, a novel voltage droop scheme for the parallel operation of voltage source converters (VSCs) in an islanded multibus microgrid is proposed. In this scheme, the voltage droop coefficient is defined as a function of respective VSC active and reactive power outputs. Thus, each VSCs voltage reference is adaptively drooped as a non-linear function of its active and reactive power outputs. This approach leads to reduction in the reactive power sharing dependence on real power control and system parameters such as mismatched connecting and line impedances. A multiobjective index is introduced for evaluating the scheme performance. The index is used as an objective function in an optimisation problem that is employed to obtain optimal parameters of the scheme. The detailed analysis shows that this scheme has a superior behaviour compared to the conventional voltage droop method, in view of the reactive power sharing and loads voltage control under all loading conditions. Simulation and experimental results show the good performance of the method for three paralleled VSCs in a multibus microgrid system.
Mitigation of harmonic disturbance at pumped storage power station with static frequency converter

This paper investigates the harmonic distortion problem and mitigation method at the Mingtan pumped storage power station in Taiwan, where six 300 MVA synchronous generator/motors are started by a static frequency converter (SFC) before the pumping stage. Since the SFC uses a 6-pulse rectifier technique, a large amount of harmonic currents are produced during the starting period. The harmonic distortion level at each bus of the power plant was very high. Especially, the total harmonic distortion (THD) of current at the lighting feeder reached up to 184%, so that power fuses were burned out. At first a 5 mH reactor was inserted in the SFC feeder and a 5th order and high pass filter was installed. However, the harmonic distortion levels were still too high, but there is no space for additional higher-order filters. Finally, the SFC is feeded with an individual transformer and the harmonic disturbance problem is avoided. This paper also gives computer simulations to investigate the harmonic distortion problems and verify the mitigation methods.
Development of a real-time monitoring system as a decision-support system for flood hazard mitigation

This study proposes a real-time monitoring system to integrate the supportive flood-related information for hazard mitigation purposes. Through integrating photography, communication, geometric information display and network technology, this system can provide the real-time monitoring images at the critical gauge stations, inundation-prone areas and important hydraulic facilities during floods. With the development of mobile monitoring modules, the maneuverability of users and facilities could be significantly improved. Users can easily employ mobile phones to receive or report real-time flood-related information at any place and time. Furthermore, the water-level image recognition method is developed and applied to the selected monitoring stations for acquiring early warning of flood events. In final, an application scenario is given to illustrate how this system can greatly improve the effectiveness and efficiency of emergency responses to flood hazard mitigation for the decision-makers.
Vehicle Handling Improvement by Active Steering

Summary This paper first analyses some stability aspects of vehicle lateral motion, then a coprime factors and linear fractional transformations (LFT) based feedforward and feedback H 8 control for vehicle handling improvement is presented. The control synthesis procedure uses a linear vehicle model which includes the yaw motion and disturbance input with speed and road adhesion variations. The synthesis procedure allows the separate processing of the driver reference signal and robust stabilization problem or disturbance rejection. The control action is applied as an additional steering angle, by combination of the driver input and feedback of the yaw rate. The synthesized controller is tested for different speeds and road conditions on a nonlinear model in both disturbance rejection and driver imposed yaw reference tracking maneuvers.
A Coupled, Field Hydrology – Open Channel Flow Model: Theory

A coupled, field hydrology and stream routing model is presented. It simulates field hydrology and routes field outflow through a canal network. Water levels in the canal can suppress field drainage. Backwater conditions and flooding in the stream are simulated. Sensitivity analysis for runoff events with one-half- to two-year return periods found watershed outflow to be sensitive to (in order of importance) time of concentration in the fields, bottom slope of the main channel, hydraulic conductivity of the soil, subsurface drain spacing in the field, and channel roughness. The simulated outflow was only moderately dependent on surface storage and was not dependent on channel depth and width, rooting depths or drainable porosity. The model can make multiple year simulations and can be used to analyze hydrologic effects of water management systems, changes in land use practices, tidal effects, and channel constrictions such as weirs or partial ditch blockage.
Condition monitoring and fault diagnosis in a domestic car engine using a neural network

The use of microelectronics in motor vehicle technology is well established, although a relatively recent innovation in comparison with the lengthy history of the motor car. In the automobile engine, the spark plug is in direct contact with the combustion processes and examination of the time varying voltage due to the spark ignition system at the spark plug provides a robust method of monitoring the engine. It has been shown that this waveform, subjected to neural network analysis, forms a mechanism which allows the monitoring of the engine for fault diagnosis or control. The technique potentially provides a convenient method of accurately sensing the /spl lambda/ of the engine. An investigation by the author and fellow researchers to demonstrate the feasibility of the technique has been described previously (R.J. Howlett et al., 1996); a summary of this work to date is presented.
Some second thoughts on electromechanical coupling

An electromechanical transducer can be regarded as an energy converter, and also as an impedance inverter. It could be significant for understanding the transduction process to introduce a new generalized concept, inversive impedance, which is defined as a ratio of the open‐circuited voltage caused by a motion at the mechanical end of a transducer to the exciting current required to produce the same motion, i.e., a ratio of the receiving (voltage) sensitivity of a transducer to its sending (current) sensitivity. Thus the electrical driving‐point impedance is composed of an impedance without coupling and a inversive impedance, which is induced by electromechanical coupling, and is constant at a given frequency for a particular transducer. The transduction process or the impedance inversion process can be described by only three independent parameters [L. ‐F. Ge, J. Acoust. Soc. Am. 91, 2326 (A) (1992)], and determined uniquely by a mapping between the electrical driving‐point impedance and its mechanical lo.
La técnica DInSAR: bases y aplicación a la medición de subsidencias del terreno en la construcción

Subsidences are defined as slow and gradual movements of the terrain or built surface. These may affect all types of terrains, and are caused by tension-induced changes for many reasons, such as lowering water tables (groundwater extraction), underground mining (minerals, coal, salt), excavation of tunnels, extraction of oil or gas, slow processes of dissolution and lixiviation of materials, consolidation of soft soils, organic soils,. The measurement and monitoring of land subsidences are the major components of infrastructures’ auscultation in the construction and monitoring phases. In many cases, subsidences occur gradually and may be recognized before they cause damage in the works. The most common procedure for subsidence’s control in engineering until now, is based on the use of instrumentation and methodologies for surveying such as precision levelling, inclinometers, photogrammetry, laser scanning and DGPS (Differential Global Positioning System). In the last decade a new technique is emerging, DInSAR (Differential Interferometry Synthetic Aperture Radar), which is based on the detection of small variations in altitude from the phase difference calculation between pairs of radar images (satellite’s data acquired from active sensors in the microwave region) covering the same area of study. This article presents the evolution of this technique for measuring surface land subsidence and its application to various fields with satisfactory precision results. It presents a review on the use of DInSAR for monitoring and measuring subsidence of land and earth structures in Construction and in the fields of Geotechnics, Hydrology and Volcanology.
Performance Analysis of Photonic Packet Switching Employing Multiple Groups of Partially Shared Buffering

An optical packet switching architecture employing multiple groups of partially shared buffering is proposed and its performance on packet contention resolution is analyzed. Simulation results are present and comparison of packet loss probability between single group of partially shared buffering and multiple groups of partially shared buffering of the same total size is carried out. Significant improvement on packet loss probability can be reached by grouping the partially shared buffer into multiple subsets, especially when the partially shared buffer is large.
A Case Study into the status of Requirements Management in the South African defence industry

In the systems engineering domain, there are several processes that are necessary for success, one of them is requirements engineering. This is a study of the requirements management process, traceability tools and workforce in the defence environment. A review of the literature suggested that good requirements management is important for success in projects; tools can be an enabler and the workforce can negatively or positively influence the requirements process. The author is an employee of Armscor and works on capital acquisition programmes in a project management capacity. Prior investigations within Armscor, the acquisition and procurement agency for the Department of Defence (DOD), revealed that problems exists in managing requirements internal and externally. The objective of this research was to determine the extent of these problems specifically focussed on the requirements process, the supporting tools and the workforce influences. The research followed a multiple case study strategy. It was a qualitative study with semi‐structured interviews conducted with respondents from four organisations i.e. DOD, Armscor and two Defence Industry Organisations namely DIO1 and DIO2. The results revealed that the requirements processes on the higher organisational levels required improvements and the problems discussed in the literature review were similar; tools played an important role in facilitating good requirements management and creating traceability. The workforce issues contributed largely to poor requirements management.
Harmonic estimation in a power system using adaptive perceptrons

The paper presents an adaptive neural network approach for the estimation of harmonic components of a power system. The neural estimator is based on the use of an adaptive perceptron comprising a linear adaptive neuron called Adaline. The learning parameters in the proposed algorithm are adjusted to force the error between the actual and desired outputs to satisfy a stable difference error equation. The estimator tracks the Fourier coefficients of the signal data corrupted with noise and decaying DC components very accurately. Adaptive tracking of harmonic components of a power system can easily be done using this algorithm. Several numerical tests have been conducted for the adaptive estimation of harmonic components of power system signals mixed with noise and decaying DC components. Data from a laboratory test is used to validate the performance of this new approach.
Design and demonstration of flapping wing device powered by LIPCA

In this paper, we present our recent progress in application of LIPCA (LIghtweight Piezo-Composite Actuator) to design and demonstration of a flapping wing device. The flapping device has flexible wings actuated by the LIPCA. The device is designed such that it can create twist motion during up- and down-stroke like bird or insect wings. The motion could be generated by using LIPCA actuator pivoted to the wing. The wing can bend and twist due to bending-twist coupling of the specially designed pivot system. Experimental results show that the properly designed flapping device powered by LIPCA can create anisotropic motion that is often required for producing effective thrust and lift forces in bird or insect flight.
UDWDM system with original tunable coherent receiver

In the paper we focus on problems of a coherent wavelength division multiplexing system with a gigahertz optical carrier frequency spacing generated by original optical comb source. We propose novel a receiver configuration of a coherent ultra dense WDM system (CoUDWDM) and compare features of a single photodiode and a balanced receiver design. The developed concept of a coherent receiver assumes selection of optical channels by the microwave section. We present simulation results of CoUDWDM system operation.
Selection of Cognitive Users in Cooperative Spectrum Sensing

Cooperative spectrum sensing under network overhead constraints is studied. To protect the primary user well, the detection probability must exceed the predefined threshold. Based on the protection of the primary user, the constraints on optimal number of cognitive users are defined by weighting the detection performance and the usage efficiency in a target function. The analysis of the target function is given under energy fusion strategy in the fusion center. The simulation results show the validity of the constraints.
Compositional Optimum Design of the Ceramic Composite with Immune Genetic Algorithm

In this paper, the immune genetic algorithm (IGA) is used to optimize the compositions of the Al2O3/SiC/Ti(C,N) ceramic composite material. Corresponding to the optimal mechanical properties such as fracture toughness, hardness and flexural strength, the optimum material compositions have been achieved. The convergent speed of IGA is faster than that of the single immune algorithm, and the number of iteration is also reduced obviously. As a result, the efficiency of optimization is increased.
Electrically Conductive, Optically Responsive, and Highly Orientated Ti3C2Tx MXene Aerogel Fibers

Aerogel fibers, which combine the lightweight and multimesoporous properties of aerogel with the flexible and slender characteristics of the fiber, have received growing attention in the fields of smart fabrics, flexible electronic devices, and transparency‐determined optics. Herein a pure Ti3C2Tx MXene aerogel fiber, showing an intriguing oriented mesoporous structure, ultrahigh electrical conductivity, and electrothermal/photothermal dual‐responsiveness, is fabricated via a simple dynamic sol–gel spinning and subsequent supercritical CO2 drying. MXene aerogel fibers exhibit tunable porosity (96.5–99.3%), high specific surface area (up to 142 m2 g−1), and low density (down to 0.035 g cm−3). Benefiting from the metal‐like conductive MXene nanosheets and their high orientation induced by dynamic sol–gel wet spinning, the resultant Ti3C2Tx MXene aerogel fibers display ultrahigh conductivity up to 104 S m−1, which far surpasses the known aerogel materials (including aerogel monoliths, aerogel fibers, and aerogel films) reported in the literature. In addition, MXene aerogel fibers also have excellent electrothermal/photothermal dual‐responsiveness due to high electrical conductivity and remarkable light absorption ability. The combination of these characteristics makes MXene aerogel fibers with encouraging potential in flexible wearable devices, smart fabrics, and portable equipment applications.
Vauxhall invests in robots at luton

418 robots have been installed at Vauxhall Motors’ plant in Luton as part of a £136 million refurbishment project to prepare the factory for the launch of the new Vectra. The bulk of the robots are employed in the body‐in‐white area, with 50 per cent performing handling operations and the rest for spot welding, stud welding and the application of adhesives. Describes some of the more innovative robotic tasks including the laser welding of the inner reinforcement panels to the bonnet [with 20 stitch welds performed in 30 second] and the fitting of windscreens and windows.
Análisis del color y el soleamiento en las Torres de Quart de Valencia (España)

In the Towers of Quart (s. XV) in the city of Valencia (Spain), an exhaustive chromatic measurement has been done of the remains of colour pigment found on the three distinct materials used in the external facade walls. The sun lighting exposure on the building surfaces has also been studied. The paper describes and justifies the process for making an accurate study of the state of the colour and its illumination by the sun, which enables guidelines to be established for renovation works on the monument.
Theoretical stress strain model for confined concrete

A stress‐strain model is developed for concrete subjected to uniaxial compressive loading and confined by transverse reinforcement. The concrete section may contain any general type of confining steel: either spiral or circular hoops; or rectangular hoops with or without supplementary cross ties. These cross ties can have either equal or unequal confining stresses along each of the transverse axes. A single equation is used for the stress‐strain equation. The model allows for cyclic loading and includes the effect of strain rate. The influence of various types of confinement is taken into account by defining an effective lateral confining stress, which is dependent on the configuration of the transverse and longitudinal reinforcement. An energy balance approach is used to predict the longitudinal compressive strain in the concrete corresponding to first fracture of the transverse reinforcement by equating the strain energy capacity of the transverse reinforcement to the strain energy stored in the concret.