Wire Configuration Research Articles

Electric Field Intensity Assessment on Curved Wires for Domestic Installations

The increasing complexity of domestic electrical installations necessitates a thorough understanding of electric field intensity, particularly when dealing with curved wires. This paper presents the results on the assessment of the electric field intensity in curved wire configurations, which are commonly encountered in residential settings due to architectural constraints. This study employs both theoretical and simulation approaches with the help of the Finite Element Based Software (COMSOL Multiphysics). The theoretical and simulations were used for a case of straight wire to allow validation of the model through comparing simulation results with the theoretically computed electric field intensity using mathematical formula. Later on, the COMSOL Multiphysics were used to compute electric field intensity under various curvature radii. The results of maximum electric field intensity against curvature radii were then plotted as scatter in excel and then fitted by the equation from the trendline option. The results show that the curvature of wires significantly influences electric field distribution. The electric field intensity was observed to be much higher for a case of small curvature radius as compared to larger curvature radius. For example, for the type of the geometry presented in this paper to represent the PVC wire used in domestic buildings’ electrical installations, the maximum electric field intensity for curvature radius of 0.025 mm was observed to be about 7 times for a case when the curvature radius was 10 mm. In additional, the power equation was found to model well the relationship between the maximum electric field intensity and curvature radius of the geometry presented in this paper

Design method of transverse gradient coils based on nonuniform rational B-spline (NURBS) curves.

To propose a hybrid transverse gradient coil design method that leverages current density-based methods and nonuniform rational B-spline (NURBS) curves to optimize the performance and manufacturability of gradient coils. Our method begins by generating an initial wire configuration using a density-based method. Then, we fit NURBS curves to the configuration, and adjust the control parameters of these curves to meet performance requirements. To ensure adequate spacing and even distribution of wires, an objective function utilizing the sigmoid function to modulate the distances between adjacent wires is constructed. Critical factors including gradient efficacy, linearity, eddy current, and torque, are incorporated as constraints. The piecewise nature of the curves provides the flexibility to independently control specific segments without impacting others. We validated our method by designing three shielded transverse gradient coils: a whole-body coil, an ultra-short whole-body coil, and an ultra-short asymmetric head coil. The primary design objectives were to improve linearity and maintain gradient efficiency. All optimized coils demonstrated significant linearity across large diameters of spherical volumes (DSVs), while gradient efficiency, eddy currents, and torque were well-balanced. The objective function effectively managed the wire concentrations required for high linearity, ensuring even wire arrangement and adequate spacing. We leveraged the flexibility of the curves to individually tailor wire paths for specific objectives, such as preventing interference between coils and passive shimming and accommodating wire connections and cooling circuits. This method provides a versatile and effective approach for designing high-performance and manufacturable gradient coils.

Design and construction of the cylindrical drift chamber for the COMET Phase-I experiment

COMET is an experiment at J-PARC that searches for the charged lepton flavor violating process of neutrino-less muon-to-electron conversion (μ→e conversion) in a muonic atom. The COMET Phase-I experiment, which represents the first stage of its staged approach, utilizes the cylindrical drift chamber (CDC) as the main detector to measure the momentum of electrons emitted from μ→e conversion in a 1 T magnetic field. The CDC is designed for optimal performance to achieve the best momentum resolution and effectively separate the μ→e conversion electron signal from background signals. This design entails adapting He:i-C4H10 (90:10) as its chamber gas and employing an all-stereo wire configuration. This document provides a comprehensive overview of the CDC detector, encompassing design considerations, mechanical structure, construction methodologies, and results of performance evaluations conducted using cosmic-rays.

Inductive mode selective damping of structural vibrations

AbstractStructural vibrations pose significant challenges in various engineering applications and require effective damping strategies to improve the overall performance and longevity of systems. While some oscillations can significantly reduce the longevity of systems, others might contribute positively to the overall system performance. Thus, this contribution presents a novel method of an inductive damping concept, that targets only specific vibrational modes based on their mode shapes. By analyzing the used inductive damping element in the context of a single degree of freedom oscillator, it is shown, that it functions as an ideal viscous damper only if the dynamics of the electric part of the system are neglected. The concept of mode selective damping is presented, using two of these damping elements in an oscillator chain with three masses. By altering the wiring configurations connecting the two damping elements in the electrical domain, the damping behavior can be manipulated to selectively damp only specific modes according to their mode shapes.

Paradigm Shift in Sports Science: The IOT-Enhanced Agility-Pad for Athletic Performance Evaluation

This paper explores the development and implementation of an agility monitoring system, aiming to provide real-time assessment of an athlete's agility. The need for such technology to facilitate instant and remote agility assessment has become increasingly apparent in the field of sports science. Unfortunately, progress in this area has been relatively slow until the emergence of IoT (Internet of Things) technology, which presents a promising avenue for athlete agility monitoring through telemetering. The core of this innovative system consists of an agility pad and a real-time monitoring module, with communication facilitated by LabVIEW software. Our approach involves rigorous testing, including unit testing of the agility pad, which serves as an MQTT publisher, the server, which functions as an MQTT broker, and the monitoring module, acting as an MQTT subscriber. In addition to these technical aspects, this article showcases various outcomes of our research. These include the designs of two activity diagrams, a comprehensive conceptual framework for agility monitoring, the database structure, communication designs for the agility pad, a wiring schematic, a 3D model of the agility pad, and the corresponding wiring configuration. We have successfully constructed two sets of agility pads, each integrated with an MCU system (ESP8266) and a dedicated database architecture designed for agile monitoring. One significant achievement of our work is the identification of the optimal delay interval required on the agility pad to prevent data loss on the MQTT broker. Furthermore, we have effectively developed a mechanism for detecting and addressing abnormal data during each testing phase, which contributes to the robustness and reliability of the system. This paper not only highlights the innovative technology behind the IOT-Infused Agility-Pad but also underscores its potential to revolutionize the assessment of athletic performance, offering coaches and athletes real-time insights into agility progress.

Energy-efficient neural network using an anisotropy field gradient-based self-resetting neuron and meander synapse

Neuromorphic computing (NC) is considered a potential solution for energy-efficient artificial intelligence applications. The development of reliable neural network (NN) hardware with low energy and area footprints plays a crucial role in realizing NC. Even though neurons and synapses have already been investigated using a variety of spintronic devices, the research is still in the primitive stages. Particularly, there is not much experimental research on the self-reset (and leaky) aspect(s) of domain wall (DW) device-based neurons. Here, we have demonstrated an energy-efficient NN using a spintronic DW device-based neuron with self-reset (leaky) and integrate-and-fire functions. An “anisotropy field gradient” provides the self-resetting behavior of auto-leaky, integrate, and fire neurons. The leaky property of the neuron was experimentally demonstrated using a voltage-assisted modification of the anisotropy field. A synapse with a meander wire configuration was used to achieve multiple-resistance states corresponding to the DW position and controlled pinning of the DW. The NN showed an energy efficiency of 0.189 nJ/image/epoch while achieving an accuracy of 92.4%. This study provides a fresh path for developing more energy-efficient DW-based NN systems.

Machine Learning Inspired Nanowire Classification Method based on Nanowire Array Scanning Electron Microscope Images.

This article introduces an innovative classification methodology to identify nanowires within scanning electron microscope images. Our approach employs advanced image manipulation techniques in conjunction with machine learning-based recognition algorithms. The effectiveness of our proposed method is demonstrated through its application to the categorization of scanning electron microscopy images depicting nanowires arrays. The method's capability to isolate and distinguish individual nanowires within an array is the primary factor in the observed accuracy. The foundational data set for model training comprises scanning electron microscopy images featuring 240 III-V nanowire arrays grown with metal organic chemical vapor deposition on silicon substrates. Each of these arrays consists of 66 nanowires. The results underscore the model's proficiency in discerning distinct wire configurations and detecting parasitic crystals. Our approach yields an average F1 score of 0.91, indicating high precision and recall. Such a high level of performance and accuracy of ML methods demonstrate the viability of our technique not only for academic but also for practical commercial implementation and usage.

Equivalence of flexible stripline and coaxial cables for superconducting qubit control and readout pulses

We report a comparative study on microwave control lines for a transmon qubit using (i) flexible stripline transmission lines and (ii) semi-rigid coaxial cables. During each experiment, we performed repeated measurements of the energy relaxation and coherence times of a transmon qubit using one of the wiring configurations. Each measurement run spanned 70–250 h of the measurement time, and four separate cooldowns were performed so that each configuration could be tested twice. From these datasets, we observe that changing the microwave control lines from coaxial cables to flexible stripline transmission lines does not have a measurable effect on coherence compared to thermal cycling the system or random coherence fluctuations. Our results open up the possibility of large-scale integration of qubit control lines with integrated component with planar layouts on flexible substrate.

Comparison of Flow Reduction Efficacy of Nominal and Oversized Flow Diverters Using a Novel Measurement-assisted in Silico Method

PurposeThe high efficacy of flow diverters (FD) in the case of wide-neck aneurysms is well demonstrated, yet new challenges have arisen because of reported posttreatment failures and the growing number of new generation of devices. Our aim is to present a measurement-supported in silico workflow that automates the virtual deployment and subsequent hemodynamic analysis of FDs. In this work, the objective is to analyze the effects of FD deployment variability of two manufacturers on posttreatment flow reduction.MethodsThe virtual deployment procedure is based on detailed mechanical calibration of the flow diverters, while the flow representation is based on hydrodynamic resistance (HR) measurements. Computational fluid dynamic simulations resulted in 5 untreated and 80 virtually treated scenarios, including 2 FD designs in nominal and oversized deployment states. The simulated aneurysmal velocity reduction (AMVR) is correlated with the HR values and deployment scenarios.ResultsThe linear HR coefficient and AMVR revealed a power-law relationship considering all 80 deployments. In nominal deployment scenarios, a significantly larger average AMVR was obtained (60.3%) for the 64-wire FDs than for 48-wire FDs (51.9%). In oversized deployments, the average AMVR was almost the same for 64-wire and 48-wire device types, 27.5% and 25.7%, respectively.ConclusionThe applicability of our numerical workflow was demonstrated, also in large-scale hemodynamic investigations. The study revealed a robust power-law relationship between a HR coefficient and AMVR. Furthermore, the 64 wire configurations in nominal sizing produced a significantly higher posttreatment flow reduction, replicating the results of other in vitro studies.

The Effect of Twisted Wire Configuration on the Stability of External Fixator: A Biomechanical Study

The Ilizarov fixator is a type of external fixator that is used to treat patients who have suffered injuries from accidents, bone shortening, or nonunion of the bone. The principle behind the Ilizarov fixator is that thin wires (called Kirschner wires) are used to support the bones and connect them to framed rings. Before being fastened to the rings, the wires are tensioned and drilled through the bones. This study suggests using a new parallel wires configuration at the same level on the same ring and two revised versions, which are divergent and convergent models, and compare them with standard wires, 60 angle wires model. All models were designed using SolidWorks, a computer-aided design (CAD) software, and then analyzed in four conditions (axial compression, medial bending, posterior bending, and torsion) with Finite Element Analysis (FEA) using Ansys Workbench 2020 R2. Mechanical testing was conducted to validate the FEA results, A simple model consisting of a single ring, two K-wires, and polylactic acid (PLA) cylinders was utilized in a tensile test. It has been concluded from the results that the parallel model and its improvement have higher stiffness to axial compression, medial bending, and torsion, but a lower posterior bending stiffness, except the divergent model with 8-hole separation which has a relatively acceptable stiffness for posterior bending.

A high‐power electromagnetic source for disabling improvised explosive devices

AbstractUltra‐wideband (UWB) microwave sources driven by specialised pulsed power generators have experienced a considerable development in the last decade due to their wide domain of new applications such as defence or counter‐terrorism activity. The authors present the main findings of a research dedicated to the development of a pulsed power‐driven electromagnetic field source for disabling improvised explosive devices (IED). The pulsed power generator driving the source is a 13‐stage compact Marx producing voltage pulses reaching an amplitude of 0.5 MV, with a pulse repetition frequency (PRF) of up to 100 Hz. The generator is coupled to a bipolar pulse forming line, providing bipolar pulses with a dV/dt of around 1.6 MV/ns. This pulsed power system feeds an array composed of 16 Koshelev‐type UWB antennas through an impedance matching transformer. The resulting electromagnetic source is capable to produce pulsed electric fields (PEFs) having a figure‐of‐merit (FOM) of 1 MV. First, practical experiments were carried out to study the effects of the PEFs on targets. The targets used in the present study are M2B type flashbulbs, known to have the same susceptibility as the US army M6 detonator. Different configurations of wires (shielded, twisted, etc) with different lengths were used in connecting items inside these targets. The tests were performed by placing the flashbulbs at different distances to determine the essential parameters (i.e., amplitude, duration, and frequency range) of the PEFs required to trigger them. An overview of the experimental campaign and the main findings are also presented followed by conclusions.

Machine Learning Inspired Nanowire Classification Method based on Nanowire Array Scanning Electron Microscope Images

Background This article introduces an innovative classification methodology to identify nanowires within scanning electron microscope images. Methods Our approach employs advanced image manipulation techniques in conjunction with machine learning-based recognition algorithms. The effectiveness of our proposed method is demonstrated through its application to the categorization of scanning electron microscopy images depicting nanowires arrays. Results The method’s capability to isolate and distinguish individual nanowires within an array is the primary factor in the observed accuracy. The foundational data set for model training comprises scanning electron microscopy images featuring 240 III-V nanowire arrays grown with metal organic chemical vapor deposition on silicon substrates. Each of these arrays consists of 66 nanowires. The results underscore the model’s proficiency in discerning distinct wire configurations and detecting parasitic crystals. Our approach yields an average F1 score of 0.91, indicating high precision and recall. Conclusions Such a high level of performance and accuracy of ML methods demonstrate the viability of our technique not only for academic but also for practical commercial implementation and usage.

Disinfection of Bacteria in Aerosols by Applying High Voltage to Stranded Wire Electrodes.

The inactivation of airborne pathogenic microorganisms is crucial to attenuate the dissemination of infectious diseases induced by airborne pathogens. Conventional air disinfection methodologies, such as ultraviolet (UV) irradiation and ozone treatment, have demonstrated limited efficacy. Consequently, we investigated the potential of employing pulsed voltages to effectively eradicate bacteria within aerosols. Our inquiry revealed that the bacterial disinfection rate increased proportionally with elevated applied voltage and frequency. For instance, when a pulsed voltage of 20 kV and a frequency of 500 Hz were applied, a substantial disinfection rate exceeding 6.0 logarithmic units was attained. Furthermore, with the utilization of the stranded wire anodes, the disinfection intensity could be augmented by up to 2.0 logarithmic units compared with the solid wire configuration. Through the utilization of a stranded wire electrode model, we scrutinized the electric field encompassing the electrode, revealing a non-uniform electric field with the stranded wire electrode. This observation indicated an amplified bacterial disinfection effect, aligning with our experimental outcomes. These findings significantly enhance our comprehension of efficacious approaches to electrically disinfecting airborne bacteria.

Three-dimensional graphene on a nano-porous 4H-silicon carbide backbone: a novel material for food sensing applications.

Sensors that are sensitive to volatile organic compounds, and thus able to monitor the conservation state of food, are precious because they work non-destructively and allow avoiding direct contact with the food, ensuring hygienic conditions. In particular, the monitoring of rancidity would solve a widespread issue in food storage. The sensor discussed here is produced utilizing a novel three-dimensional arrangement of graphene, which is grown on a crystalline silicon carbide wafer previously porousified by chemical etching. This approach allows a very high surface-to-volume ratio. Furthermore, the structure of the sensor surface features a large number of edges, dangling bounds, and active sites, which make the sensor, on a chemically robust skeleton, chemically active, particularly to hydrogenated molecules. The interaction of the sensor with such compounds is read out by measuring the sensor resistance in a four-wire configuration. The sensor performance has been assessed on three hazelnut samples: sound, spoiled, and stink bug hazelnuts. A resistance variation of about ∆R = 0.13 ± 0.02 Ω between sound and damaged hazelnuts has been detected. Our measurements confirm the ability of the sensor to discriminate between sound and damaged hazelnuts. The sensor signal is stable for days, providing the possibility to use this sensor for the monitoring of the storage state of fats and foods in general. © 2023 Society of Chemical Industry.

Progress on the reduction of silver consumption in metallization of silicon heterojunction solar cells

In this work, we have demonstrated the possibility to reduce silver consumption for highly efficient SHJ cells by fine-line screen printing using low temperature paste with a variety of screens with different meshes and openings. The achieved grid fingers were characterized for the line resistance and the printed width. Extremely narrow grid fingers with 13 μm width were realized on the 520-mesh. Compared to a standard 380-mesh, finer 520-mesh produced fingers that are on average 4 μm narrower and 8% less resistive, leading to a 0.08%abs. higher efficiency whilst reducing the overall silver consumption by 15%. Complementary simulations have shown that module wire configuration is an important driver to reduce silver consumption. Integration of test samples in modules showed that 1.6 mg/W frontside paste laydown resulted in marginally lower performance than reference samples with laydown of 4–6 mg/W.

Thermal fluid dynamics of the effect of filler wire on deposition rate and bead formation intending plasma arc-based DED

The influence of filler wire configuration, such as size and geometry, on the deposition rate (DR) and bead formation, has been studied in wire arc-based directed energy deposition (WADED), but the fundamental physics underlying its effect on wire melting and melt pool dynamics remains unclear. In this paper, a series of plasma arc-based DED (plasma-DED) experiments were conducted to investigate the impact of five different filler wire configurations on DR and bead dimensions. The coupling behaviours of wire melting, metal transfer and melt pool dynamics under the five filler wire configurations were also simulated numerically using the authors' recently developed wire-feeding model. The calculated wire melting and bead cross-sections are consistent with the experimental images and measurements. The results demonstrate that the filler wire significantly affects the highest DR by altering wire melting and metal transfer behaviours through changes in arc energy absorption. The filler wire with a rhombus geometry which is closer to a Gaussian-like arc distribution than the flat wire was shown to get higher DR and more stable metal transfer. Furthermore, different filler wire configurations lead to distinct melt pool behaviours, including temperature distribution and flow velocity, due to various metal transfer behaviours and arc shading effects. This study sheds light on the fundamental physics underlying the impact of filler wire on wire melting and bead formation for the first time. The methods and findings can guide improving DR and controlling bead shape in the plasma-DED process.

Winding Loss Suppression in Inverter-Fed Traction Motors via Hybrid Coil Materials and Configurations

In a typical inverter-fed AC drive system, the stator windings carry a current with a large harmonics content, resulting in an increased AC loss. In this paper, the additional copper losses caused by non-sinusoidal currents are investigated for different magnet wire topologies, including the flat conductor, stranded, and litz wires. Also, a two-slot simplified model is introduced for accurate prediction of the AC losses at high frequency. It is found that one of the major issues of the conventional copper coil is that the losses are not uniformly distributed across the slot, and over 70% of the losses are concentrated near the slot opening. Moreover, using the transient finite element method, different winding topologies and arrangements are simulated at the stranded level to evaluate the losses and current density for each strand under highly distorted currents. Furthermore, different coil samples are prototyped for the same slot geometries to compare their performance under the same pulse-width modulation (PWM) waveforms for a wide range of frequencies. Finally, new hybrid coil topologies are proposed, which employ different magnet wires or materials within the same slot. The results demonstrate that utilizing a mixed wire configuration can effectively mitigate the adverse effects of eddy current losses. This approach can yield up to 16–41% lower losses while also achieving a weight savings of 36–70%.

FUNCTIONAL OUTCOME OF PERCUTANEOUS TRANSOLECRANON AND LATERAL KIRSCHNER WIRE FIXATION FOR DISPLACED SUPRACONDYLAR FRACTURE OF HUMERUS IN CHILDREN

Background: Supracondylar fracture of the humerus is one of the most common fracture occurring in children. When the patients present with swelling of the elbow, there is a dilemma whether to wait for the swelling to subside or to perform closed reduction and percutaneous pinning immediately. The objective of this study was to assess the functional outcome of percutaneous transolecranon and lateral K wire fixation and to observe the outcomes associated with this K wire configuration. Methods: This was a prospective observational study done between 2021 and 2022 at Chitwan Medical College, Nepal. The study included 40 children with closed Gartland type II and III supracondylar fracture of the humerus with no neurovascular injury. They were treated within 3 days with closed reduction and percutaneous pinning using the transolecranon and lateral K-wire fixation technique. The outcome was assessed using the Flynn’s elbow Grading criteria. Results: At 12 week follow up, 7 (17.5 %) patients had excellent result, 21 (52.5%) patients had good, 8 (20%) patients had fair and 4 (10%) patients had poor result. According to Flynn’s grading system 90 % had satisfactory result and 10 % had unsatisfactory result. Four patients had loss of reduction out of which 2 had poor result and 2 had fair result. None of the patients had post operative iatrogenic ulnar nerve injury. Conclusions: The percutaneous transolecranon and lateral K-wire fixation for displaced supracondylar fracture of the humerus in children is a good treatment option when the elbow is swollen and is reliable as it prevents iatrogenic ulnar nerve injury.

Effectiveness of laser welding in cerclage wiring fixation: a biomechanical study.

Cerclage wiring is a common orthopedic procedure for fracture fixation. However, previous studies reported wiring-related perioperative complications, such as wire loosening or breakage, with an incidence rate of up to 77%. Recently, the use of laser welding on medical implants was introduced to connect biomedical materials. This study used laser technology to weld between wires after conventional cerclage fixation. We hypothesized that the laser welding could significantly increase the biomechanical properties of cerclage wiring fixation. Twenty-five wiring models underwent biomechanical tests in five cerclage wiring configurations (five models per group), namely, (1) single loop, (2) single loop with laser welding, (3) double loop, (4) double loop with one-side laser welding, and (5) double loop with two-side laser welding. Characteristics such as load to failure, mode of failure, and wiring failure were compared between groups. The biocompatibility for a 316L stainless steel wire with laser welding was evaluated via an in vitro hemolysis test. Mean load to failure of the double loop with one-side and two-side laser welding groups were 3,596 ± 346 N and 3,667 ± 240 N, which were significantly higher than for the double-loop group (2,919 ± 717 N) (p = 0.012 and p = 0.044, respectively). Conversely, no significant difference was shown in the comparison of the mean load to failure between the single loop and the single loop with laser-welded cerclage wire (1,251 ± 72 N, 1,352 ± 122 N, and p = 0.12). Untwisted wire and wire breakage were the most common mode of failure. All welding specimens revealed non-hemolytic effects from in vitro hemolysis test. Laser welding on cerclage wiring significantly increases the biomechanical property of double cerclage wire fixation. However, further biocompatibility tests and clinical studies are still recommended.

Modelling stranded wires using homogenization and the Cauer ladder method

PurposeThe purpose of this paper is to introduce a new method to model a stranded wire efficiently in 3D finite element simulations.Design/methodology/approachIn this method, the stranded wires are numerically approximated with the Cauer ladder network (CLN) model order reduction method in 2D. This approximates the eddy current effect such as the skin and proximity effect for the whole wire. This is then projected to a mesh which does not include each strand. The 3D fields are efficiently calculated with the CLN method and are projected in the 3D geometry to be used in simulations of electrical components with a current vector potential and a homogenized conductivity at each time step.FindingsIn applications where the stranded wire geometry is known and does not change, this homogenization approach is an efficient and accurate method, which can be used with any stranded wire configuration, homogenized stranded wire mesh and any input signal dependent on time steps or frequencies.Originality/valueIn comparison to other methods, this method has no direct frequency dependency, which makes the method usable in the time domain for an arbitrary input signal. The CLN can also be used to interconnected stranded cables arbitrarily in electrical components.