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This paper shows that a magnetic coating can reduce AC copper loss caused by the proximity effect based on a measured value. A solenoid coil is used for the measurement. This reduction was quantified by supplying external magnetic fields to conductors placed in a central region of the solenoid coil and measuring AC copper loss as changes in the coil's resistance. AC copper loss in aluminum flat wires was minimized by applying a magnetic coating to the wires. The experimental and FEM results confirmed the reduction. The AC copper loss was reduced by a maximum of 59% due to applying magnetic coating. © 2024 Institute of Electrical Engineers of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

Traditional wet plug charging for autonomous underwater vehicles (AUVs) limits its application. Inductive power transfer (IPT) is an effective solution to this problem. This paper proposes an arc‐shaped magnetic coupler incorporated with solenoid coils to achieve a stable and efficient output against rotational misalignment for charging AUV. The novel magnetic coupler consists of two solenoid coils and an arc‐shaped coil with a reverse winding, guaranteeing a relatively constant total mutual inductance and decoupling from each other. This magnetic coupler has the characteristics of a compact structure, an ultra‐wide coupling range, and a relatively stable equivalent mutual inductance. The experimental IPT prototype can deliver 1.29 kW with a dc–dc efficiency of 93% under the fully aligned case and 1.2 kW with a dc–dc efficiency of 91% under the misaligned case. [ABSTRACT FROM AUTHOR]

The practical implementation and parameterization of a model for estimating the magnetic force of valve solenoids involving a hysteresis model are evaluated. In a first step, popular approaches for modeling the force hysteresis of valve actuators are compared, followed by a description of the test bench used and the valve investigated. Next, the experimental procedure as well as the recorded data are described and discussed. Finally, a phenomenological modeling approach of force hysteresis is presented. The advantages and limitations are demonstrated and discussed using measured data. [ABSTRACT FROM AUTHOR]

In the field of eddy‐current testing (ECT), most studies on detection probes are primarily based on circular solenoid coils; related research on rectangular spiral coils is rare. In this study, an analytical model of the mutual inductance (MI) between two coplanar rectangular spiral coils was developed in which the two coplanar rectangular spiral coils were placed above a conductive plate. The MI calculation does not need to consider the thickness of the coils, which is consistent with the actual situation of the printed circuit boards (PCB)‐based spiral coils, and simplifies the multi‐turn rectangular spiral coil into a set of concentric single‐turn coils. Two experimental setups were constructed to verify the analytical model and they were used to detect defects in the aluminium plate. The experimental results indicate that the analytical model can be used to evaluate the performance of ECT probes using PCB‐based spiral coils, through the geometrical dimensions of the coils, centre distance and lift‐off, and so forth. Compared with traditional methods, this method can still obtain satisfactory calculation accuracy after ignoring thickness parameters. The analytical model is also an effective tool to aid in the design of detection probes and optimisation of related parameters. [ABSTRACT FROM AUTHOR]

Magnetic microrobots can be miniaturized to a nanometric scale owing to their wireless actuation, thereby rendering them ideal for numerous biomedical applications. As a result, nowadays, there exist several mechano‐electromagnetic systems for their actuation. However, magnetic actuation is not sufficient for implementation in biomedical applications, and further functionalities such as imaging and heating are required. This study proposes a multimodal electromagnetic system comprised of three pairs of Helmholtz coils, a pair of Maxwell coils, and a high‐frequency solenoid to realize multimodal locomotion and heating control of magnetic microrobots. The system produces different configurations of magnetic fields that can generate magnetic forces and torques for the multimodal locomotion of magnetic microrobots, as well as generate magnetic traps that can control the locomotion of magnetic swarms. Furthermore, these magnetic fields are employed to control the magnetization of magnetic nanoparticles, affecting their magnetic relaxation mechanisms and diminishing their thermal properties. Thus, the system enables the control of the temperature increase of soft‐magnetic materials and selective heating of magnetic microrobots at different positions, while suppressing the heating properties of magnetic nanoparticles located at undesired areas. [ABSTRACT FROM AUTHOR]

Safety instrumented systems (SIS), also known as emergency shutdowns, interlocks, and trips, are very common and critical safeguards protecting process plants. In order to maintain and test these systems, they are usually implemented with well‐engineered and controlled bypasses, typically including alarm logging, bypass authorization, and auditing. Even so, there are myriad ways to place an SIS component into bypass, sometimes without even realizing it. Many of these methods occur in the field, away from the watchful eye of the board operator. In many cases, the bypasses occur inadvertently during maintenance or operational activities and are left in place, unmanaged. Common culprits include solenoid valve latches, shutoff valve handwheels, and hand‐off‐auto switches on pump and compressors. This paper will explain how some equipment can be inadvertently put into bypass and methods for documenting and verifying that they are not in bypass using advanced mobile computing assisted car‐seal management. [ABSTRACT FROM AUTHOR]

Precise braking pressure control of a pneumatic electric braking system (PEBS) poses challenging non‐linear control problems, since it can operate in several distinct discrete processes (the pressure increasing, holding and decreasing) by switching the on‐off solenoid valves and the piston of relay valve moves irregularly. This article describes the development and experimental validation of a viable controller for an electronically controlled braking pressure based on the theory of model predictive control (MPC). The controller design consists of two parts. The non‐linear characteristic is first studied to ensure the pressure response of PEBS when the opening time is 4–10 ms in a fixed period, followed by calculation and prediction of the optimal on‐off time of inlet valve and release valve based on the current braking pressure to realize steady state. A logic rule is designed to ensure that the MPC controller and feedback control work coordinate to guarantee engineering reliability. A comprehensive system model is derived to help characterize system non‐linearities and design the MPC predictive model. Simulations and experimental results are presented finally to show how the MPC and feedback control strategy can be successfully applied to solve the braking pressure control of a PEBS in a systematic way. [ABSTRACT FROM AUTHOR]

A new semi‐analytical expression is presented based on two integrations for calculating the magnetic force of a solenoid inductor wound by rectangular cross‐section wire. The authors simplified the solenoid inductor coil to a collection of circular coils, and the current density of the coils in the radial direction which was inversely proportional to its radius is considered. The obtained expressions can be implemented by adaptive Gaussian quadrature integration with MATLAB programming. In addition, they used the filament method and the finite element method to calculate the magnetic force on the solenoid inductor coil. The correctness of the semi‐analytical expressions was verified by comparing the results of the semi‐analytical numerical method with those of the filament method and the finite element method, respectively. The derived semi‐analytical expressions of magnetic force allow a low computational time compared with the filament method and the finite element method to a specific accuracy. The calculation results show that: the solenoid inductor coil tends to compress in the axial direction, and the axial magnetic force on the outermost coils is the largest; the solenoid inductor coil tends to expand outward in the radial direction, and the radial magnetic force on the intermediate coil is the largest. [ABSTRACT FROM AUTHOR]

Summary: The vehicle height and body posture adjustment of electronically controlled air suspension (ECAS) poses great challenges to hybrid control, since it involves discrete events of solenoid valve (SV) switching and dynamic evolutions of continuous variables. This article investigates in the modeling and verification of the vehicle height and body posture adjustment control system. A nonlinear mechanism model of the ECAS which considers the pneumatic characteristics of the SV is established. On the basis of mixed logical dynamical (MLD) modeling approach, a hybrid automaton describing on–off statuses transition equations of charging SV, discharging SV and four air spring SVs is established and then is compiled into the standard MLD model by using hybrid system descriptions language, realizing the coordinated control between the vehicle height and body posture by directly adjusting the SV on–off statuses. Simulation tests and bench tests are conducted and the results are presented to show how the designed hybrid automaton can be successfully applied to solve the difficulties that exist in the ECAS. [ABSTRACT FROM AUTHOR]

Pneumatic brake systems are crucial for the operation of trains. However, due to switching characteristics of on/off solenoid valves, the precise pressure control and low switching activities of valves are difficult to guarantee simultaneously during braking. To address the issue, a hybrid model predictive control (MPC) method is proposed for implementing the multi‐objective optimisation in this paper, i.e. the precise pressure tracking and the valve switching reduction. In order to model the hybrid behaviour caused by continuous dynamics of the pressure and discrete features of solenoid valves, the mixed logic dynamical system theory is applied. Then, the braking control problem is recast as a hybrid MPC problem, which jointly optimises the pressure tracking precision and the valve switching. A mixed integer linear program is formulated to solve the MPC problem in an efficient way. Both simulation and experiment results show that the accurate pressure control and low switching activities of valves can be achieved by the proposed method when compared with existing methods. [ABSTRACT FROM AUTHOR]

This study proposes a crossed flat solenoid coupler (CFSC) for electric vehicle wireless charging. The impact of four size parameters of CFSCs on coupling coefficient and misalignment tolerance is studied using finite‐element analysis. The optimisation methodology of CFSCs considering size constraints is given. The CFSC is compared with the planar square coupler (PSC) and double D coupler (DDC) from three aspects: coupling coefficient, misalignment tolerance, and copper usage. The CFSC performs the best in the three aspects, and the DDC performs the worst. Two wireless power transfer prototypes, one employing CFSCs and the other utilising PSCs, were built to demonstrate the superiority of the proposed coupler. Primary inductor‐capacitor‐capacitor secondary series compensation topologies were employed in the two prototypes. Experiments agree well with theoretical analysis and simulations. The power transfer efficiency of the CFSC‐based prototype was 1.6% higher than the PSC‐based prototype when the Z‐axis displacement is 45 mm. [ABSTRACT FROM AUTHOR]

In this paper we address the possibility to perform imaging of two samples within the same acquisition time using coupled ceramic resonators and one transmit/receive channel. We theoretically and experimentally compare the operation of our ceramic dual‐resonator probe with a wire‐wound solenoid probe, which is the standard probe used in ultrahigh‐field magnetic resonance microscopy. We show that due to the low‐loss ceramics used to fabricate the resonators, and a favorable distribution of the electric field within the conducting sample, a dual probe, which contains two samples, achieves an SNR enhancement by a factor close to the square root of 2 compared with a solenoid optimized for one sample. [ABSTRACT FROM AUTHOR]

New solutions to a recently proposed benchmark TEAM problem for Pareto optimisation are presented. In the benchmark, an air‐cored solenoid of small size, which can be used, for example, for magnetic fluid hyperthermia, is considered. Two shape optimisations of the solenoid are proposed in the benchmark: synthesising a uniform magnetic field in a control region, considering also a sensitivity function (Problem 1) or synthesising a uniform magnetic field, simultaneously minimising the power losses (Problem 2). The benchmark is solved by means of three different nature‐inspired algorithms and a genetic one, namely micro biogeography‐inspired algorithm, wind‐driven optimisation, and the cuckoo search, taking the genetic algorithm NSGA‐II as a reference, because all these methods have proven to be effective in solving multi‐objective optimisation problems. [ABSTRACT FROM AUTHOR]

To improve the linearisation of the variable flow-regulate system under the open-loop control, a proportional solenoid valve with high-linearity performance was developed to meet that requirement of the high-precision and open-loop control. The design of the proportional solenoid valve evolves the optimisation of a magnetic circuit structure, the construction of a balanced pressure structure and the compensation of a feedforward control device. As for the solenoid, it is very challenging to meet the requirement of 95% linearity. A feedforward control device with the Bouc–Wen model and a quadratic inverse function model is a good solution to address the hysteresis problem and achieve better performance. The optimisation of a simple magnetic circuit with low sensitivity to the moving armature and a balance chamber for removing the pressure difference are both preconditions to make the compensation. The feedforward control device is the next step to eliminate the hysteresis problem and non-linear characteristics of the solenoid by solving model coefficients measured in the test. After the improvement in these aspects, the proportional solenoid valve can meet the demand of digital proportional flow control with >98% linearity and excellent repeatability, through the validation of both no-load and high-load performance tests. [ABSTRACT FROM AUTHOR]

Based on the analysis of the structure and operation mode of low-floor urban trams, the structure, principle, components and technical parameters of the anti-kink hydraulic system which specially set up were described, and the application characteristics of the hydraulic system technology were pointed out. [ABSTRACT FROM AUTHOR]

Transmembrane kinases (TMKs) are members of the plant receptor‐like kinase (RLK) family. TMKs are characterized by an extracellular leucine‐rich‐repeat (LRR) domain, a single transmembrane region and a cytoplasmic kinase domain. TMKs have been shown to act as critical modulators of cell expansion and cell proliferation. Here, the crystal structure of the extracellular domain of TMK3 (TMK3‐ECD) was determined to a resolution of 2.06 Å, with an Rwork of 17.69% and an Rfree of 20.58%. Similar to the extracellular domain of TMK1, the TMK3‐ECD structure contains two solenoids with 13 LRRs and a non‐LRR region (316–364) between the tenth and 11th LRRs. A comparison of TMK3‐ECD with other LRR‐RLKs that contain a non‐LRR region indicates that the non‐LRR region plays a critical role in structural integrity and may contribute to ligand interactions. The non‐LRR region of TMK3‐ECD is characterized by two disulfide bonds that may have critical biological implications. [ABSTRACT FROM AUTHOR]

Purpose: TRASE uses phase gradients in the RF transmit field to encode MRI data. A highly efficient twisted solenoid coil was proposed recently for TRASE imaging for transverse B0 geometries. This novel coil can be rotated to generate a phase gradient in any transverse direction, therefore, combining two such coils would double k‐space coverage for single‐axis encoding, resulting in higher spatial resolution. However, the strong inductive coupling between a pair of coaxial twisted solenoids must be overcome. Methods: Here, we demonstrate that two concentric twisted solenoids, designed using previously described Biot‐Savart calculations, can be geometrically decoupled by attaching to each a regular solenoid in series. The regular solenoid geometry resulting in minimization of mutual inductance was determined from simulations using the FastHenry2 tool. The effects on TRASE encoding performance due to the regular solenoids were assessed from simulations and experiments. Results: The maximum resulting B1 magnitude and phase distortions were 3.7% and 4.6∘, while a good isolation S12=-17.5 dB between the coil pair was obtained. TRASE experiments confirmed the double k‐space coverage, and achieved a rapid spin echo train with 128 k‐space points collected within 80 ms, allowing short T2 samples to be accurately imaged. Conclusions: This study demonstrates that a pair of twisted solenoid phase gradient RF coils can be geometrically decoupled. Advantages over active PIN diode decoupling include faster switching, lower hardware complexity, and scalability. [ABSTRACT FROM AUTHOR]

Rotational motion generates energy extractable by the energy harvester for powering electronic devices and is also useful for self‐powered sensing. An integrated triboelectric–electromagnetic–piezoelectric hybrid energy harvester induced by a multifunction magnet for rotational motion is designed and investigated herein. The hybrid energy harvester is installed on a rotating disc to create rotational motion. A cylindrical NdFeB permanent magnet (Magnet I) acts as a key movable component, reciprocating in an acrylic cylinder as the hybrid energy harvester rotates. Magnet I interacts with three different generators to achieve three power generation modes in a single motion cycle, thus improving energy harvesting efficiency. Charging 10 μF capacitors demonstrates the superior charging capability of the hybrid energy harvester compared with individual power generation components. Assisted by a rectifier circuit and capacitor, the hybrid energy harvester as a power source at 45 rpm can supply power for thermohygrometer and illuminate 111 blue LEDs. In addition, the hybrid energy harvester exhibits good stability and durability, continuously operating the triboelectric nanogenerator (TENG) unit of the hybrid energy harvester at 30 rpm for 9 h. In short, this work demonstrates a new kind of energy harvester that provides the possibility to efficiently harvest rotational mechanical energy. [ABSTRACT FROM AUTHOR]

This study first analyses the problems that the solenoid valve generates during operation. Then the electromagnetic valve was modelled and ANSYS finite element analysis simulation software was used to simulate the electromagnetic field and transient magnetic field of the solenoid valve. The magnetic induction intensity distribution diagram and magnetic field distribution diagram of the electromagnet were obtained. According to the simulation results of the solenoid valve, the magnetic flux leakage line is blocked after the magnetic isolation cover is added, the magnetic induction strength of the iron core and the valve head is increased, the leakage magnetic flux is reduced, and the structure is optimised. [ABSTRACT FROM AUTHOR]

Wear is one of the common faults in the mechanical transmission system. Detection of wear particles in lubricating oil can detect and evaluate the wear degree of mechanical equipment. The electromagnetic sensor for metal wear particle detection can be connected in series with the oil circuit, which has the advantages of full liquid flow, simple structure, distinguishing metal properties, and not being influenced by bubbles and vibration. In view of the shortcomings of the existing electromagnetic sensor for wear particle detection, the detection principle and the induction electromotive force model were studied, and the magnetic field change of the metal particles through three coil differential solenoids was analysed. The optimisation design method was proposed here, which was about the related parameters, such as the wire diameter, the coil turns, the coil widths and so on. The experimental analysis of the sensor was carried out based on detection hardware system that could provide the phase-locked amplification function. The 10-mm inner diameter sensor could detect the minimum 100-μm ferromagnetic metal abrasive particles after optimisation. The developed sensor could provide data information for the abrasive particle detection, fault diagnosis and early warning of wear degree of mechanical equipment. [ABSTRACT FROM AUTHOR]

Rectangular coils are widely used in inductive power transfer (IPT), and the self- and mutual inductances of them are key system parameters. However, the study of the rectangular coil is not enough. In this study, a series of unified analytical formulae for the self- and mutual inductance calculations of a variety of rectangular coils including filamentary coils, pancake coils and thin- or thick-walled solenoids are presented. Various positions of the rectangular coils above are discussed, and the mutual inductance formulae in the case of co-axis, co-plane, misalignment and even overlapping are given. Finally, the experimental measurements are carried out on various types of rectangular coils. The experimental results agree well with the calculated ones, which indicate the effectiveness of the proposed method. Therefore, this study provides an interesting tool for designing the transceiver of rectangular coils in IPT system. [ABSTRACT FROM AUTHOR]

Mini‐generators based on locomotion of small objects have aroused widespread attention because of their potential application in powering small‐scale electronic devices. Although improvements have been made in the development of mini‐generators, there are still some key challenges such as low power output and energy conversion efficiency, which limit the potential application of mini‐generators. Herein, through integrating a superhydrophobic surface, chemical reaction and solenoid coil/magnet into a system, an innovative mini‐generator is designed, which can convert chemical energy into electrical energy through mechanical form. As a result, the energy conversion efficiency and output power are both three hundred times higher than previously reported results and can be applied to power light‐emitting diodes without amplification. We believe that the proposed mini‐generator provides more chance for the application of self‐supplying power sources for electronic devices. [ABSTRACT FROM AUTHOR]

This study presents the design and experimental characterisation of single‐layer solenoid air‐core inductors. The analytical expressions for the winding inductance, self‐capacitance, and winding resistance are derived. The inductor properties are analysed up to the first self‐resonant frequency. The procedure to design air‐core inductors for high‐frequency (HF) applications is provided. Experimental validations of the analytical equations are given. A single‐layer air‐core 20μH inductor was designed, built, and measured. The bandwidth of the designed inductor obtained from theoretical predictions was about 100 MHz. The measured quality factor was 181 at 1 MHz. The results of this study are useful for engineers and designers in the areas of power supplies, datacentres, radio‐frequency power amplifiers, radio‐frequency transmitters, and HF filters. [ABSTRACT FROM AUTHOR]

The US Environmental Protection Agency's Office of Research and Development designed, fabricated, and installed four pipe rigs in Flint, Mich., to help the city optimize corrosion control. The lead service line (LSL) pipe loops were constructed of polyvinyl chloride pipe and fittings and welded steel channel frames. Each pipe rig consisted of four approximately 4 ft‐long sections of 0.75 in. inside diameter lead pipe that were excavated from homes fed by the Flint distribution system. The rigs were operated on a set daily on/off schedule such that a specified amount of water passed through each pipe using a solenoid valve‐operated timer system. Solenoid problems resulted in sporadic and enhanced daily flow volume (but no flow rate changes) that prevented restabilization of pipe scales. Lead levels were relatively sporadic and statistically different during this period. After the solenoids were replaced, the lead pipe rigs were successfully conditioned, and lead release with consistent influent water chemistry became relatively stable. Average lead levels across all 16 loops ranged between approximately 2 and 5 μg/L after the solenoid replacement. The lead results were consistent with levels measured from LSLs from homes in the city during sequential sampling efforts. [ABSTRACT FROM AUTHOR]

When double‐break vacuum circuit breakers (VCBs) interrupt the fault current, the series arc will generate their individual magnetic fields in different breaks. The magnetic field in one break will influence the arc in another break if the magnetic field is strong enough or the two breaks are very close. In this case, an interactive magnetic field effect happens. This field is also called the bias magnetic field (BMF). BMF can cause anode erosion and affect the performance at current zero. The distribution of BMF and the optimal configuration of the double‐break VCBs were obtained by the electromagnetic field simulation using the Ansoft Maxwell software. Based on the simulated magnetic field data, in the experiments, the interaction between the series vacuum arcs in double‐break VCBs was equivalent to the interaction between a single vacuum arc and the magnetic field generated by a Helmholtz coil. A high‐speed CMOS camera was used to record the trajectory of the vacuum arc plasma under different BMFs with different types of contacts. The results show the BMF can increase the arc voltage, and the arc becomes unstable. When the BMF becomes stronger, the arc voltage increases, and the arc becomes more unstable. In addition, for different types of contacts, the development process of the arc and the influence level are different under the same BMF. For a Wan‐type transverse magnetic field (TMF) contact or strong BMF, metal sputtering is evident and anode erosion becomes serious. For a cup‐type axial magnetic field (AMF) contact, the influence of BMF on the series arc plasma in double‐break VCBs is less than that of the Wan‐type TMF contact. The results of this work may be helpful for the design of compact double‐break VCBs. [ABSTRACT FROM AUTHOR]

SUMMARY We have designed and developed a tri-stable rotary solenoid actuator, which has a simple structure and simple operation. The plunger has two stabilities at the extreme positions along an angular stroke and the third stability at the center of it. The third has been successively achieved by using the electromagnetic restoring torque, which is designed to be larger than the inertia torque. The dynamic characteristics were determined by utilizing an optimal design program that is specially constructed based on the response surface method in order to design the coil winding and the power supply for the coil excitation. A prototype solenoid was constructed and used to verify the tri-stable motions and accuracy of the previously constructed design program. [ABSTRACT FROM AUTHOR]

Summary: We propose a model‐based method that allows to estimate the magnetic force accurately, hence the armature displacement of linear solenoids. The nonlinear electrodynamical model of solenoids is used. The unscented Kalman filter is applied to analyze the current transient response, and the dynamics of the solenoid is estimated at each time instant. Furthermore, a new approach to estimate the varying internal solenoid reluctance, from the nonlinear model of solenoids, is proposed. The estimation is performed for each value of the current and predicted while the armature is moving. This leads to an accurate computation of the electromotive magnetic force related to the velocity of the moving actuator's component, thus permitting to know the system dynamics accurately. [ABSTRACT FROM AUTHOR]

SUMMARY There are two types of the transformers in a contactless power transfer system: solenoid type (H-shaped) and circular type transformers. These two types of transformers are not compatible because their magnetic field structures are different. An Hc type transformer that is compatible with both transformer types has been proposed. The Hc type receiver adds a central magnetic pole by dividing the winding coil of the H-shaped receiver. The Hc type receiver can change the magnetic field structure by changing the connections of the divided windings and can receive power from both types of transmitters. In this study, we conducted a circuit analysis and evaluated the performance of the Hc type transformer. [ABSTRACT FROM AUTHOR]

SUMMARY The magnetic properties of Nd-Fe-B magnets with 0.5 mm and 1 mm cubes in size were measured with a vibrating sample magnetometer equipped with high-temperature superconducting magnet (VSM_HSC). With the VSM_HSC, high sweep speed and high accuracy in magnetization measurement were achieved. Furthermore, magnetic properties of Nd-Fe-B magnets were measured with the VSM_HSC, pulsed field magnetometer, and a permeameter. It was found that the squareness of demagnetization curves appeared depending on the measurement systems. [ABSTRACT FROM AUTHOR]

We establish an asymptotic profile that sharply describes the behavior as [ABSTRACT FROM AUTHOR]

SUMMARY Odor sensing system with high sensitivity and selectivity is expected to be realized by using biological mechanisms such as olfactory receptor. We have already developed a cell-based odor sensing system which acquires odorant concentration as a fluorescent intensity change. In the measurement, however, an artifact is likely to happen due to lack of stable and reproducible methods for delivering odorants to biological cells. Therefore, we developed and evaluated the automated flow measurement system which can simultaneously control pump, solenoid valve, and camera. Our system realized automation of solution supply and fluorescent measurement. As a result, our system could reduce artifacts and repeatedly performed measurements with the same sensor cells. [ABSTRACT FROM AUTHOR]

The purpose of this article is to propose algebraic techniques to solve symmetric complex-valued systems. In particular, we focus on the systems which arise from the modeling of electromagnetic fields in the frequency domain. These systems usually present a very ill-conditioned number, so specific preconditioning techniques are supposed to be used. Finally, both analytical and numerical reference tests are proposed on the simple case of the magnetic field produced by a solenoid containing conductive or non-conducting materials. [ABSTRACT FROM AUTHOR]

The beam condition monitoring leakage (BCML) system is a beam monitoring device in the compact muon solenoid (CMS) experiment at the large hadron collider (LHC). As detectors 32 poly-crystalline (pCVD) diamond sensors are positioned in rings around the beam pipe. Here, high particle rates occur from the colliding beams scattering particles outside the beam pipe. These particles cause defects, which act as traps for the ionization, thus reducing the charge collection efficiency (CCE). However, the loss in CCE was much more severe than expected from low rate laboratory measurements and simulations, especially in single-crystalline (sCVD) diamonds, which have a low initial concentration of defects. After an integrated luminosity of a few [ABSTRACT FROM AUTHOR]

This study presents a method using inverse hyperbolic functions to calculate the mutual and self‐inductance inductance of coaxial circular filamentary coils, thin‐wall solenoids, disk coils, and coils with rectangular cross‐section in air. A generalised expression is given for any combination of these coils, which only requires numerical integration with one variable. Singularities are fully analysed and methods to resolve the singularities are presented in this study. When calculating the self‐inductance of a disk coil or a thin‐wall solenoid, the proposed method involves an improper integral, and the accuracy of the proposed method is limited unless a quadrature rule applicable to improper integrals is applied. For other situations, results by the proposed method were compared with those in the literature, and they were in excellent agreement. [ABSTRACT FROM AUTHOR]

Rationale For the development of on-site mass spectrometry for security and safety, point-of-care analysis, etc., the gas volume introduced into the vacuum should be reduced to a minimum. To cope with this demand, a discontinuous atmospheric pressure interface using a solenoid pulse valve was developed. Methods The sample gas was introduced discontinuously into the ionization cell with a volume of 0.17 cm3. The sampled gas in the cell was ionized by an alternating current (ac) corona discharge. The generated ions were sampled through a 0.25 mm i.d. and 12 mm long nickel capillary into the vacuum of a time-of-flight mass spectrometer. Results A gas flow rate of ~25 mL/min was achieved with the 1 Hz pulse valve operation and 20 ms valve opening time. Sub-ng limits of detection for less volatile compounds such as explosives and drugs were obtained. Conclusions Due to its compact size and low gas load to the vacuum, this new interface may be useful for applications in miniaturized mass spectrometry. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Magnetic resonance imaging (MRI) is a robust tool to monitor oil displacement processes in porous media. Conventional MRI measurement times can be lengthy, which hinders monitoring time-dependent displacements. Knowledge of the oil and water microscopic distribution is important because their pore scale behavior reflects the oil trapping mechanisms. The oil and water pore scale distribution is reflected in the magnetic resonance T2 signal lifetime distribution. In this work, a pure phase-encoding MRI technique, spin echo SPI (SE-SPI), was employed to monitor oil displacement during water flooding and polymer flooding. A k-t acceleration method, with low-rank matrix completion, was employed to improve the temporal resolution of the SE-SPI MRI measurements. Comparison to conventional SE-SPI T2 mapping measurements revealed that the k-t accelerated measurement was more sensitive and provided higher-quality results. It was demonstrated that the k-t acceleration decreased the average measurement time from 66.7 to 20.3 min in this work. A perfluorinated oil, containing no 1H, and H2O brine were employed to distinguish oil and water phases in model flooding experiments. High-quality 1D water saturation profiles were acquired from the k-t accelerated SE-SPI measurements. Spatially and temporally resolved T2 distributions were extracted from the profile data. The shift in the 1H T2 distribution of water in the pore space to longer lifetimes during water flooding and polymer flooding is consistent with increased water content in the pore space. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Curli are functional bacterial amyloids produced by an intricate biogenesis machinery. Insights into their folding and regulation can advance our understanding of amyloidogenesis. However, gaining detailed structural information of amyloids, and their tendency for structural polymorphisms, remains challenging. Herein we compare high-quality solidstate NMR spectra from biofilm-derived and recombinantly produced curli and provide evidence that they adopt a similar, well-defined b-solenoid arrangement. Curli subunits consist of five sequence repeats, resulting in severe spectral overlap. Using segmental isotope labeling, we obtained the unambiguous sequence-specific resonance assignments and secondary structure of one repeat, and demonstrate that all repeats are most likely structurally equivalent. [ABSTRACT FROM AUTHOR]

Two identical unprinted dielectric slabs are placed above a dual-polarised (DP) stacked-patch feed antenna to transform its less-directive radiation into almost equal and high-gain DP beams in two frequency bands. The dual-band operation is achieved by engineering the reflection characteristics of a classical all-dielectric superstructure such that cavity resonance condition is satisfied in two frequency bands. A prototype of this dual-polarised electromagnetic band gap resonator antenna with a frequency ratio of 1.245 has been fabricated and measured peak gains of 17 and 16.6 dBi at 10.6 and 13.15 GHz, respectively, and cross-polarisation levels of less than -18 dB, have been achieved. The proposed antenna has a simple configuration and is easy to manufacture, making it a good candidate for DP point-topoint wireless links. [ABSTRACT FROM AUTHOR]

We have created an accelerated corrosion environment for sintered Nd-Fe-B magnets in e-motor applications. E-motor working conditions are complex, and standard magnet corrosion tests only cover a small subset of possible parameters (e.g., samples are usually tested in the demagnetized state). In this work magnetized and demagnetized sintered Nd-Fe-B magnets were placed in gearbox oil, and exposed to temperature cycles (θmax = 130 °C) using an autoclave. Beforehand the magnets were pre-immersed in saturated water-based salt solution to account for water and de-icing salt that might interfuse gearbox oil over time. The corrosive behavior was studied for two commercial magnet grades, 'high grade' (8.9 wt% dysprosium) and 'low grade' (3.1 wt% dysprosium); and monitored by weight loss, structural analysis (scanning electron microscopy and energy dispersive X-ray) as well as magnetic characterization. The magnetized samples corroded significantly faster than their demagnetized counterparts. Strong differences in the corrosion rates of the 'low grade' and 'high grade' material are discussed. We concluded that the magnetization state is one key parameter that needs to be considered in corrosion tests for e-motor applications. [ABSTRACT FROM AUTHOR]

Electrical resistivity and its thermal coefficient (TCR) of TiW alloy thin films which were prepared by using two different sputtering systems have been investigated. System A is a DC-magnetron sputtering system equipped with a single composite-target that allows the contents controllable by an external field of solenoid as reported in previous papers (Sakurai and Takeda, Abstract of E-MRS 2005 Fall Meeting [1] and Sakurai et al., Solid State Phenom. 154, 175 (2009) [2]). The system A prepared specimens with the range of 21.6 to 36.6 at% of W-contents. The TCR varies from minus to plus at 32 at% of W-content. On the other hand, System B is a RF-magnetron sputtering system equipped with multi-targets and multi-sputtering-sources. The system B covered the whole binary composition ranges by controlling power ratio for two independent sputtering sources. The resistivity characteristics show a parabolic curve with the maximum value on Ti-rich contents. The TCR decreases at the contents that shows the maximum resistivity, but the TCR is always plus and does not cross zero. Difference of the properties by using the two systems will be discussed. In the system A, the background is exhausted by an oil diffusion pump and the pressure is higher (lower vacuum degree) than the background in the system B with a turbo molecular pump. This suggests that zero TCR would be achieved by introducing the controlled impurities (O2 or N2) into the binary alloy films. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Transportin SR2 (TRN-SR2) is a β-type karyopherin responsible for the nuclear import of specific cargoes, including serine/arginine-rich splicing factors. The protein has been implicated in a variety of human diseases, including HIV infection, primary biliary cirrhosis and limb-girdle muscular dystrophy 1F. Towards understanding its molecular mechanism, a 2.9 Å resolution crystal structure of human TRN-SR2 complexed with the small GTPase Ran has been determined. TRN-SR2 is composed of 20 α-helical HEAT repeats forming a solenoid-like fold. The first nine repeats form a `cradle' for the binding of RanGTP, revealing similarities but also differences with respect to the related importin 13 complex. [ABSTRACT FROM AUTHOR]

Although nuclear magnetic resonance (NMR) is one of the most powerful analytical techniques, it has not been widely used as a non-destructive, non-contact inline industrial sensor. A short background of NMR spectroscopy fundamentals and instrumentation is presented along with its potential applications and limitations for real-time analysis in the manufacturing sector. NMR signals are generated in the presence of a magnetic field normally produced by expensive large and heavy magnets which have been the major limiting factor in the use of NMR analysis in factories. However, the last decade has brought substantial advances in the development of cheaper, smaller, and lighter permanent magnets based on rare earth materials that use Halbach and unilateral configurations. Small and light cryogenic-free superconducting magnets are now offered in the market and are opening a new era in manufacturing. It is expected that soon NMR spectroscopy will be applied to monitor the chemical and physical properties of complex feedstock mixtures and reactions in real time which is the ultimate goal of precise process control. [ABSTRACT FROM AUTHOR]

We consider the non-stationary three-dimensional viscous flow in a bounded domain, with the lateral surface containing microscopic surface irregularities. Under the assumption of a smooth flow in the domain without roughness, we prove that there is a smooth solution to a problem with the rough boundary. In the papers by Jäger and Mikelić, the friction law was obtained as a perturbation of the Poiseuille flows. Here, the situation is more complicated. Nevertheless, after studying the corresponding boundary layers and using the results on solenoidal vector fields in domains with rough boundaries, we obtain rigorously the Navier friction condition. It is valid when the size and amplitude of the imperfections tend to zero. Furthermore, the friction matrix in the law is determined through a family of auxiliary boundary-layer type problems. Effective equations approximate velocity at order O ( ε) in the H1-norm, uniformly in time, and O( ε3 ∕ 2) in the L2-norm, also uniformly in time. Approximation for the pressure is O( ε3 ∕ 2) in the [ABSTRACT FROM AUTHOR]

In this reported work, a femtosecond-laser-based microsolidifying method was employed to fabricate three-dimensional (3D) microsolenoids by injecting liquid metal into helicalmicrochannels in fused silica and solidifying the liquid metal, and a proposed finite element method-3Dvector simulation approach was used to analyse the structure influence. An improved femtosecond laser irradiation followed by chemical etching technology was used to fabricate the complex 3D microchannels, in which an optimal laser power compensation strategy of tuning laser power from 7 to 12 mW was involved. Asilanisation process was carried out before the injection process to facilitate the injection of gallium. 3D numerical simulations of the microsolenoids were carried out by an electromagnetic-coupled analysis method; and a simulation-based co-energy calculation method was used to evaluate the inductance of the 3D microsolenoids. 3D microsolenoids of optimised configurations were then achieved according to the analytical results. [ABSTRACT FROM AUTHOR]

It is one of our dreams to mechanically recover lost body capabilities for damaged humans. Realistic humanoid robots composed of such machines require muscle motion actuators controlled by all pulling actions. In particular, antagonistic pairs of bi-articular muscles are very important in animal motions. A system of actuators is proposed using the electromagnetic force of solenoids with a stroke length of over 10 cm and a strength of about 20 N, which are needed to move the real human arm. The devised actuators are based on the development of recent modern electromagnetic materials, where traditional materials cannot give such a possibility. Composite actuators are controlled by a high-capability computer and software to perform genuine motions. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 184(2): 10-19, 2013; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.22369 [ABSTRACT FROM AUTHOR]

This paper describes a method for determining the density of contact trace objects with magnetic levitation (MagLev). MagLev measurements accurately determine the density (±0.0002 g/cm3) of a diamagnetic object and are compatible with objects that are nonuniform in shape and size. The MagLev device (composed of two permanent magnets with like poles facing) and the method described provide a means of accurately determining the density of trace objects. This method is inexpensive, rapid, and verifiable and provides numerical values-independent of the specific apparatus or analyst-that correspond to the absolute density of the sample that may be entered into a searchable database. We discuss the feasibility of MagLev as a possible means of characterizing forensic-related evidence and demonstrate the ability of MagLev to (i) determine the density of samples of glitter and gunpowder, (ii) separate glitter particles of different densities, and (iii) determine the density of a glitter sample that was removed from a complex sample matrix. [ABSTRACT FROM AUTHOR]

This work presents a new design of disc infiltrometer, which, associated with a microflowmeter (MF) and a solenoid valve set, makes it possible to automate the infiltration rate ( Q) measurements at different soil pressure heads (ψ). The MF consists of a 13·8-cm long and 1·5 mm i.d. pipe, with a pressure transducer connecting the two ends of the MF, inserted in a water-flow pipe that connects the Mariotte tube and the water-supply reservoir of the disc infiltrometer. Water flow is calculated from the head losses in the MF. Changes in ψ in the bubble tower, automatically affected when the infiltration rate reaches steady state, are controlled by a datalogger connected to four solenoid valves. The new design was tested in laboratory and field conditions, and the results showed that the MF allows the soil water infiltration rates to be correctly estimated for different soil characteristics. The solenoid valve set plus datalogger system satisfactorily monitored the changes in ψ and allowed the measurement time to be optimized. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

We present a three-degree-of-freedom planar actuator that can position a mover over a wide range of locations in the yaw and translational directions. In conventional planar actuators, which have multiple pairs of permanent magnets and armature coils, the mover cannot be displaced by large amounts unless the planar actuator has numerous armature coils. Furthermore, the movable area of conventional planar actuators in the yaw direction is quite narrow because of the interference between the different pairs of permanent magnets and armature currents that occurs due to the yaw displacements. The proposed planar actuator has only six stationary armature conductors for two sets of three-phase currents. The mover constantly faces all the armature conductors, and hence, it can be subjected to driving forces for three-degree-of-freedom movement anywhere on a plane parallel to the stator surface. Therefore, the movable area of the actuator can be easily expanded by increasing the length of the armature conductors. However, the driving forces depend on the yaw angle, and large yaw displacements impede the generation of sufficiently strong driving forces. In this paper, we present the results of experiments conducted to determine the movable area of our proposed planar actuator in the yaw direction. The experimental results indicate that sufficient torques in the yaw direction can be generated when the yaw displacement is less than 26°. The driving force acting on the mover is a function of the yaw angle and is periodic with a 90° period due to the central symmetry of the actuator. The experimental results also indicate that the mover can travel over 90° displacements in the yaw direction. Thus, we successfully demonstrate the three-degree-of-freedom large movement of the planar actuator by controlling two sets of three-phase currents. © 2011 Wiley Periodicals, Inc. Electr Eng Jpn, 177(4): 51-61, 2011; Published online in Wiley Online Library (). DOI 10.1002/eej.21208 [ABSTRACT FROM AUTHOR]

Purpose: MR-visible markers have already been used for various purposes such as image registration, motion detection, and device tracking. Inductively coupled RF (ICRF) coils, in particular, provide a high contrast and do not require connecting wires to the scanner, which makes their application highly flexible and safe. This work aims to thoroughly characterize the MR signals of such ICRF markers under various conditions with a special emphasis on fully automatic detection. Methods: The small markers consisted of a solenoid coil that was wound around a glass tube containing the MR signal source and tuned to the resonance frequency of a 1.5 T MRI. Marker imaging was performed with a spoiled gradient echo sequence (FLASH) and a balanced steady-state free precession (SSFP) sequence (TrueFISP) in three standard projections. The signal intensities of the markers were recorded for both pulse sequences, three source materials (tap water, distilled water, and contrast agent solution), different flip angles and coil alignments with respect to the B0 direction as well as for different marker positions in the entire imaging volume (field of view, FOV). Heating of the ICRF coils was measured during 10-min RF expositions to three conventional pulse sequences. Clinical utility of the markers was assessed from their performance in computer-aided detection and in defining double oblique scan planes. Results: For almost the entire FOV (±215 mm) and an estimated 82% of all possible RF coil alignments with respect to B0, the ICRF markers generated clearly visible MR signals and could be reliably localized over a large range of flip angles, in particular with the TrueFISP sequence (0.3°-4.0°). Generally, TrueFISP provided a higher marker contrast than FLASH. RF exposition caused a moderate heating (≤5 °C) of the ICRF coils only. Conclusions: Small ICRF coils, imaged at low flip angles with a balanced SSFP sequence showed an excellent performance under a variety of experimental conditions and therefore make for a reliable, compact, flexible, and relatively safe marker for clinical use. [ABSTRACT FROM AUTHOR]