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For an electric locomotive traction motor, it is necessary to maintain relatively low vibration and noise due to the higher design standards. By using effective motor control strategies and implementing current harmonic suppression schemes, motor efficiency and vibration and noise suppression can be effectively improved. This study investigates the current harmonic suppression strategy for permanent magnet synchronous motors by (1) constructing a mathematical model of the permanent magnet motor to explore the sources of low-order harmonics currents such as fifth and seventh harmonics, as well as high-order harmonics at switch frequencies and their multiples, and analyzing the electromagnetic force characteristics generated by the current, and (2) establishing a vector control system for the permanent magnet motor. To suppress the fifth and seventh harmonic components in the current, a resonance controller is constructed, which utilizes the parallel connection of a resonator and PI controller to achieve low-order harmonic suppression. The factors affecting the effectiveness of the resonance controller's suppression are also analyzed. The experiments are conducted, and the current harmonic suppression scheme constructed in this study can effectively reduce the harmonics in the current, thereby reducing motor vibration and noise. [ABSTRACT FROM AUTHOR]

Motor faults not only damage the motor body but also affect the entire production system. When the motor runs in a steady state, the characteristic frequency of the fault current is close to the fundamental frequency, so it is difficult to effectively extract the fault current components, such as the broken rotor bar. In this paper, according to the characteristics of electromagnetic force and vibration, when the rotor eccentricity and the broken bar occur, the vibration signal is used to analyze and diagnose the fault. Firstly, the frequency, order, and amplitude characteristics of electromagnetic force under rotor eccentricity and broken bar fault are analyzed. Then, the fault vibration acceleration value collected by a one-dimensional dilated convolution pair is extracted, and the SeLU activation function and residual connection are introduced to solve the problem of gradient disappearance and network degradation, and the fault motor model is established by combining average ensemble learning and SoftMax multi-classifier. Finally, experiments of normal rotor eccentricity and broken bar faults are carried out on 4-pole asynchronous motors. The experimental results show that the accuracy of the proposed method for motor fault detection can reach 99%, which meets the requirements of fault motor detection and is helpful for further application. [ABSTRACT FROM AUTHOR]

The exploration of electromagnetic vibration sources is very important for the vibroacoustic reduction of a squirrel‐cage induction motor. However, the influence of high‐order electromagnetic force on the electromagnetic vibration of induction motor has not been studied before. The influence of high‐order electromagnetic force on motor vibration is investigated in detail. Firstly, the Maxwell stress tensor method is applied to calculate the electromagnetic force. Next, the force transfer function is introduced to describe the phenomenon that the high‐order electromagnetic force induces the low‐mode motor vibration. Then, the high‐order forces in the air gap of the induction motor are analysed in detail and their effects on motor vibration are simulated. Finally, an experiment is conducted to verify the correctness of the analytical scheme. [ABSTRACT FROM AUTHOR]

This article presents a type of power injection and free resonance decoupled wireless power transfer (WPT) system, the double-switch independent power injection and free resonance wireless power transfer (IPIFR-WPT) system working in CCM. Based on the stroboscopic mapping model, the theoretical results show that the operation point of the proposed WPT system is determined by itself instead of the switching control strategy. Specifically, once the voltage on the primary capacitance does not decrease to the input voltage in the free-resonance process, the diode in series would not turn on and the system would not switch to the power injection process. Therefore, there is a wide soft-switching margin to ensure the system operating in soft-switching states. Another characteristic of the proposed WPT system is the monotonicity between output power and operation cycle, which presents a simple power control method. And since the soft-switching margin may have intersection under dynamic coupling coefficient, the proposed system maintains soft-switching states with a fixed switching strategy and presents advantage to resist the dynamic change of coupling coefficient. All the characteristics of the proposed WPT system mentioned above have been verified in both theory and experiment. [ABSTRACT FROM AUTHOR]

Choristoneura metasequoiacola Liu, 1983 is an important caterpillar species that specifically infests the leaves and branches of Metasequoia glyptostroboides Hu & W. C. Cheng 1948 with short larval infestations, long-term dormancy, and has a limited distribution in Lichuan, Hubei, China. The complete mitochondria genome of C. metasequoiacola was determined by using Illumina NovaSeq, and analyzed based on previously annotated sibling species. In total, we obtained mitochondria genome with 15,128 bp in length, circular in shape with a double-stranded closed ring structure, including 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes, and an AT-rich region. Of which the nucleotide composition was highly A + T biased, accounting for 81.98% of the whole mitogenome. Thirteen protein-coding genes (PCGs) were 11,142 bp; Twenty-two tRNA genes and AT-rich region were 1,472 and 199 bp, respectively. Phylogenetically, the relationship between Choristoneura spp. (containing C. metasequoiacola) and Adoxophyes spp. was closer than any other two genera from Tortricidae, and the relationship between C. metasequoiacola and C.murinana was the closest among nine sibling species from that genus, which helps to explain species evolution within the family Tortricidae. [ABSTRACT FROM AUTHOR]

For the fully resonant wireless power transfer (WPT) system, the high coupling of the converter and the resonant network introduced many problems, such as frequency splitting, the power curve peak limit, and the strict switch strategy. To solve these problems, this paper proposed a new six-switch topology based on the full–-bridge converter. With the unique structures containing two capacitor-isolated switches and a source-isolated diode, the system decouples the converter and the resonant network, and its modes have been decoupled, called the independent power injection and free resonance WPT (IPIFR–WPT) system. The capacitor-isolated switches and the source-isolated diode make the converter operate only when the voltage on the primary capacitor is equal to the source voltage, and the source will be isolated by the diode when the capacitor voltage is great than the source, which provides a wide time margin for the switches of the converter to turn on in advance. In this margin, the operation point is self-determined the same whenever the switches turn on so that the system's performance is consistent. Based on this characteristic, the system can self-adapt a dynamic change in system parameters, with at least 15% tolerance for the coupling coefficient and 14% for the load resistance. [ABSTRACT FROM AUTHOR]

Purpose: The present study aimed to evaluate the clinical value of the combined detection of soluble T cell immunoglobulinand mucin domain molecule 3 (sTim-3) and pepsinogen (PG) in sera for gastric cancer (GC) diagnosis. Patients and Methods: The double antibody sandwich method was used to establish a highly sensitive time-resolved fluorescence immunoassay for the detection of sTim-3. Serum sTim-3, PGI, and PGII levels in 149 GC patients (123 first-diagnosis GC patients and 26 post-GC patients), 81 patients with benign gastric disease (BGD), and 73 healthy controls were quantitatively detected. The clinical diagnostic value of the combined detection of sTim-3 and PG in GC was analyzed. Results: Serum sTim-3 levels in GC (20.41 ± 9.55 ng/mL) and BGD (16.50 ± 9.76 ng/mL) patients were significantly higher (P < 0.001) than those in healthy controls (9.22 ± 3.40 ng/mL). Combined detection of sTim-3 and PGI/PGII (AUC: 0.9330, sensitivity: 86.44%, and specificity: 91.78%) showed a high diagnostic value for GC. When the level of PGI/PGII was less than 12.11 and that of sTim-3 was greater than 14.30 ng/mL, the positive rate of the control group was reduced to 0%, and the positive detection rate of GC was 54.47%. In addition, in post-operative patients, serum sTim-3 levels in the recurrence group (33.56 ± 4.91 ng/mL) were significantly higher than those in the no recurrence group (11.95 ± 5.16 ng/mL). Conclusion: sTim-3 levels in BGD and GC sera were significantly higher than those in the control group sera. Additionally, sTim-3 serum levels can predict recurrence in post-operative patients. Compared with PG alone, the combined detection of serum PG and sTim-3 can significantly improve the detection sensitivity and specificity of BGD and GC. [ABSTRACT FROM AUTHOR]

The common method to mitigate the slot-frequency vibration and noise of the permanent magnet (PM) motors is skewing the stator slot or skewing the PM. However, the limitation of this method in pole-frequency vibration reduction exists. In this article, one method by adopting the piecewise stagger PM pole with a continuous skew edge is proposed to reduce the pole-frequency and slot-frequency vibration for surface-mounted permanent magnet (SPM) synchronous machines. First, the analysis of the radial force acting on the stator teeth is conducted. Basing on this, the limitation of the skewing slot method in reducing the vibration is revealed. In order to solve this problem, a piecewise stagger PM pole with a continuous skew edge for pole-frequency and slot- frequency vibration reduction is proposed and its principle of vibration reduction is presented in detail. The finite element models of three 6-pole/36-slot SPM motors are built to simulate the radial force. Finally, two 6-pole/36-slot SPM motors are manufactured and the experimental results validate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

The analytical methods are widely used to predict the vibration and noise of the permanent magnet motors in industry applications. In the traditional analytical method, the influence of the teeth is ignored and a large error of vibration calculation will occur in the slotted motor. In this article, a high-precision analytical method is proposed for vibration calculation of motors based on tooth modeling. First, the electromagnetic forces on each tooth of stator of the motor under no load and load are calculated. Then, the transfer function from the force acting on the teeth to the vibration on the surface of the shell is derived and verified by finite-element method (FEM). Next, the superposition method is introduced and used to superimpose the vibration excited by the force of all teeth to calculate the total vibration acceleration of the motor surface. Finally, the FEM and experiments are conducted to verify the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

The coupling of converters with resonant networks poses significant challenges for frequency tracking and power control in inductive power transfer (IPT) systems. This paper presents an implementation method that addresses these issues by dividing the system's operation into two distinct states: self-oscillating and power-injecting. Based on these states, a phase-closed loop is constructed. Within this closed loop, the phase tracking unit detects and tracks frequency drift, while the power regulating unit incorporates an integrator and adopts a control variable to adjust the output power by modifying the duration of the power injecting state. Meanwhile, the oscillating unit operates in the self-oscillating state. Operating in this manner, the system achieves self-oscillation and demonstrates the capability to effectively track and compensate for system variations within a single cycle. A verification prototype has been constructed, and it demonstrates that the converter within it completely decoupled from the resonant network. Experimental results validate that altering the control variable solely affects the duration of the power-injecting state, allowing for independent control of the output power. When the control variable changes from 2.0 V to 3.5 V, the output power changes from 178 W to 519 W while the self-oscillating state remains unchanged. Furthermore, the system accurately tracks frequency changes, even under significant variations in the coupling coefficient or load, without compromising the power injection state. When the air gap changes from 3 cm to 12 cm, the duration of the self-oscillating state changes from 22.1 μs to 26.3 μs, while the power injecting state remains unchanged. This approach exhibits a robust performance, particularly suitable for dynamic IPT systems sensitive to parameter variations. [ABSTRACT FROM AUTHOR]

The magnetic field including tooth effect can be calculated by the tooth harmonic permeance. However, the mechanical pivot role of tooth is always neglected in vibration analysis and the slotted stator is considered as a simple cylinder. In this article, the mechanical pivot role that the tooth plays in vibration analysis is illustrated, where the transfer function of force is proposed to represent the process of force from the top of tooth to the yoke. First, the magnetic pivot role of tooth in magnetic field analysis is described by the tooth harmonic permeance. Then the force on the top of tooth is transferred to the yoke by the transfer function of force, after that the yoke can be considered as a cylinder. Based on the pivot role of tooth, the phenomenon that the high order force can cause the low mode vibration is explained and clarified straightforwardly. Not only the fractional slot permanent magnet synchronous motor (PMSM), but also the integer slot PMSM, are analyzed to demonstrate the universality of these methods. Finally, the finite element method simulation, and the experiments on one fractional slot PM motor and one integer slot PM motor, are applied to validate the theory. [ABSTRACT FROM AUTHOR]

Because the root of pole-frequency vibration is the fundamental component of magnetic field, which is the basis of electromechanical energy conversion, by now no effective reduction method of pole-frequency vibration has been proposed, even few literatures has touched on this. In this article, one method by adding some permanent magnet (PM) interpoles to fill the force valley and then reduce the pole-frequency vibration for surface-mounted PM synchronous machines, is proposed and verified by experiments on prototype motors. First, a general expression of radial force density, including the amplitude, frequency, and spatial order, of a PM motor is investigated in detail. Based on this, the deep reason of pole-frequency vibration is ascribed as the valley of force density and the zero-crossing area of magnetic flux density. To fill the force valley and reduce the vibration, some PM interpoles are arranged between original main PM poles and its principle of vibration reduction is presented. A three-dimensional weak-coupling electromagnetic- mechanical finite-element model is built to simulate the radial force and the vibration of the PM motors. Finally, to validate the proposed method and finite-element method results, two 6 poles/36 slots PM motors are manufactured and the experiments are conducted. [ABSTRACT FROM AUTHOR]

The electromagnetic vibration of permanent magnet brush dc (PMBDC) motors has its distinct feature, where only slot-frequency related components exist. Skew slot technique is naturally recalled to mitigate the slot-frequency vibration. Unfortunately, the straight skew slot normally used is not as effective as the mitigation of tooth harmonic electromotive force (EMF) or cogging torque. First, in this paper, the principle of vibration mitigation by straight skew is discussed and compared with mitigation of tooth harmonic EMF and cogging torque. The reason for poor effect of straight skew slot is illustrated by a specifically-designed experiment and finite-element method (FEM) simulation. In order to solve this problem, the zigzag skew PM pole technique is proposed for PMBDC motors for the first time, which overcomes the disadvantage of straight skew slot. The pulsating radial force and bending moment, two main causes of electromagnetic vibration, are derived and analyzed analytically and by the three-dimensional FEM for zigzag skew PM poles. At last, the experiments on two PMBDC motors, one with straight skew slots and the other with zigzag skew PM poles, are conducted to verify the effectiveness of the zigzag pole technique. [ABSTRACT FROM AUTHOR]

The experimental modal test of the structure of the driving motor has always provided a major contribution to understand and control the vibration phenomena encountered in practice. The hammer test is a common experimental method to obtain a mathematical model of the structure and to validate the theoretical model and finite element method model. However, the hammer or the real vibration exciter will increase the test cost. In this article, an electromagnetic vibration exciter is proposed to achieve the frequency response functions and then the modal parameters can be extracted. Its principle of modal parameters estimation is presented and described in detail. The finite-element analysis and experiments of a 6p/36s permanent magnet motor have been conducted to verify the proposed method. [ABSTRACT FROM AUTHOR]

For the integer slot permanent-magnet (PM) driving synchronous motor, the zeroth-mode slot frequency vibration and noise play a significant vibroacoustic role in the low-frequency domain. For conventional analysis in literature, it is usually assumed that the zeroth-mode vibration is caused by the zeroth-order radial force harmonic. But in this paper, the genuine reason for zeroth-mode vibration is proposed and discussed in detail, which is different from the conventional analysis. The teeth chopping effect is proposed and demonstrates that the slot number order radial force is the root of the zeroth-mode vibration of the motor. After the analysis of the zeroth-mode vibration in existing research work is presented, the teeth chopping effect is introduced and described. The amplitudes of the zeroth-order and slot number order forces are compared with an analytical method, while their amplitudes and caused deformations of these forces are calculated with the finite-element method (FEM). Finally, to validate the analytical and FEM results, a 6-pole 36-slot PM driving motor is manufactured and tested, and the results are in good agreement with those of the FEM results. [ABSTRACT FROM AUTHOR]

As for the sensorless control of interior permanent magnet synchronous motor (IPMSM), conventional high frequency (HF) pulsating signal injection method is widely used, which uses band-pass filter (BPF) and low-pass-filter (LPF) based phase-locked-loop (PLL), however it may face the problems of poor stability and long convergence time. Therefore, an improved signal demodulation algorithm based on moving-average-filter (MAF)-PLL is proposed. MAF, which makes full use of the HF signal periodicity and half-wave symmetry, has higher bandwidth and better harmonics suppression ability than BPF or LPF. Furthermore, a proportional-integral (PI) regulator is used to gain the rotor speed and an integrator is applied to estimate rotor position. Compared with the conventional method, the proposed method gets rid of BPF and LPF, contributing to improving the stability and dynamic performance. Besides, undetermined parameters are reduced to one, i.e., window length of MAF, avoiding complex parameters design and selection. The proposed HF pulsating injection method has simpler signal demodulation process and is easy to implement. Finally, the experimental results have verified the feasibility and effectiveness of proposed method. [ABSTRACT FROM AUTHOR]

This paper focuses on the electromagnetic vibration and its reduction in PM brush dc motors. First, the air gap flux density distribution and the radial force density distribution are derived in detail, and compared with the results of the finite element method. Next, two types of vibration sources, called pulsating force and bending moment, are analyzed. Then, two passive improvement methods, called varied PM pole width in axial direction and copper ring, are proposed to reduce the magnetic forces and their vibration, and their principles of the vibration reduction are described in detail. For further explanation, a rotor-skewed motor is used for comparison, and the radial force on the motor is discussed and the influence of four different thicknesses of copper ring on the motor vibration is analyzed. Finally, three 2p/24s sample motors are manufactured and the experimental vibration results confirm the analysis and the proposed improvement technique. [ABSTRACT FROM AUTHOR]

For the field-oriented control of interior permanent magnetic synchronous motor (IPMSM) drives, it is difficult to tune the gains of a proportional-integral (PI) controller without knowing the system parameters exactly. Besides, system parameters variations will deteriorate the performance, even lead to instability. Therefore, a multi-objective controller design method of IPMSM drives is proposed based on a D-partition method. Discrete time domain (DTD) D-partition method is adopted instead of a continuous time domain (CTD) D-partition method, because CTD analysis ignores the inherent discrete nature of control implementation. Besides, a stability region area is derived as the performance criteria; thus, the effects of system parameters variations on stability can be analyzed. Furthermore, by carefully dealing with the interaction between PI gains and time-domain specifications, frequency-domain specifications, as well as system parameters uncertainties, a desired region is obtained, from which the optimized PI gains can be selected. Comparing with conventional methods, it is more convenient and intuitive to achieve a multi-objective design by using the proposed method. Experimental results verify the effectiveness of the proposed design method. [ABSTRACT FROM AUTHOR]

This paper presents a PM pole with varied width in the axial direction for vibration mitigation in permanent magnet brush dc motors, which is proposed to decrease the deformation caused by radial pulsating force and bending moment together. First, the air gap flux density distribution and radial force density distribution are derived in detail. After two types of vibration modes and their reasons as pulsating force and bending moment are analyzed, the difficulty in vibration mitigation is pointed out. By investigating the change rule of the pulsating force and bending moment with PM pole width, a type of PM pole with varied width in the axial direction is proposed. Its principle of deformation reduction is presented, and the optimized pole shape is derived. A three-dimensional finite-element method is used to calculate the magnetic field, Maxwell force, modal analysis, and deformation of motors. In order to verify the effectiveness of the proposed method, the vibration of the proposed motor is compared with the other three types of traditional motors, including skewing slot or skewing pole. Finally, experimental results of two types of motors are compared to validate the proposed technique. [ABSTRACT FROM AUTHOR]

This paper presents the detail analysis of the radial force and bending moment responsible for vibration in the stator permanent magnet synchronous motors (PMSMs). The vibration characteristics, especially vibration mode, of stator PMSM are studied. First, the air-gap flux density distribution and radial force density distribution are derived in detail. Then, two types of vibration modes, called pulsating and bending modes, and their reasons as pulsating force and bending moment are analyzed and elaborated which are not analyzed and verified before. In addition, the relationships between these two vibration shapes and pole width, pole number, and slot number are analyzed. To confirm the analysis and theory, the multi-probe mode-included test method of vibration acceleration is used to obtain the vibration mode information of motors, and the experimental results on a 6-pole/36-slot stator PMSM match well with the simulation results. [ABSTRACT FROM AUTHOR]

This paper presents a new method by sticking a copper ring on the permanent magnet pole of the permanent magnet brush dc (PMBDC) motor to reduce the electromagnetic vibration. First, the air-gap flux density distribution and radial force density distribution are derived and the principle of the electromagnetic vibration reducing technique by the copper ring is analyzed in detail. Then, finite-element method is used to calculate the Maxwell force and the vibration spectrum of a 2-pole 24-slot PMBDC motor and a modified motor. Finally, experimental results are given to validate the proposed technique, by testing the vibration spectrum of the two prototype PMBDC motors. It is shown that the acceleration of the motor with copper ring can reduce the vibration effectively compared with the origin motor, and the reduced ratio can be up to 40%. [ABSTRACT FROM AUTHOR]

The vibration mode of electric machines is an important characteristic of vibration, which is useful for finding the vibration sources with different frequencies, but has always been neglected before. In this paper, the vibration characteristics, especially the vibration mode, of permanent magnet (PM) brush DC motors are studied. First, the air gap flux density distribution and radial force density distribution are derived in detail and compared with the results of the finite-element method. Then, two types of vibration modes, called pulsating and bending modes, and their reasons as pulsating force and bending moment are analyzed and elaborated, which have not been analyzed and verified sufficiently before. In addition, the relationships between these two vibrations and pole width, pole number, and slot number are analyzed. The main modal shapes and their frequencies are acquired from the modal test. To confirm the analysis and theory, the multiprobe mode-included test method of vibration acceleration is proposed and emphasized to obtain the vibration mode information of motors, and the experimental results on a PM brush DC motor match well with the simulation results. [ABSTRACT FROM AUTHOR]

According to coupling way between the magnetic field and the structural order, structure mode is discussed by engaging finite element (FE) method and both natural frequency and modal shape for a dry-type air-core reactor (DAR) are obtained in this paper. On the basis of harmonic response analysis, electromagnetic force under PWM (Pulse Width Modulation) voltage excitation is mapped with the structure mesh, the vibration spectrum is gained and the consequences represents that the whole structure vibration predominates in the radial direction, with less axial vibration. Referring to the test standard of reactor noise, the rules of emitted noise of the DAR are measured and analyzed at chosen switching frequency matches the sample resonant frequency and the methods of active vibration and noise reduction are put forward. Finally, the low acoustic noise emission of a prototype DAR is verified by measurement. [ABSTRACT FROM AUTHOR]

An automatic stage transition converter for an inductive power transfer system is presented in this paper. An effective control strategy with two working stages of independent energy injection stage and free resonance stage is employed in the proposed converter. With the automatic stage transition strategy, when the frequency of the resonance network changes, the ending time of the free resonance stage is automatically determined. At the same time, the phase angle of the free resonance stage is automatically set as half a resonant cycle. As the stage transition is not triggered by the switches, the switch motion can be executed in advance of the transition moments. Time margins are offered for every switch in the converter, which make the switching moments of the switches flexible and the control simple. Another feature of this converter is that during the energy injection stage, the energy is injected into the inductor independently. Therefore, the input power can be easily regulated by adjusting the energy injection time. A prototype for the converter and the inductive power transfer system was implemented experimentally. From the experimental results, the automatic stage transition and power regulation capability of the proposed converter are verified. The switches all operated at the soft switch condition. When the energy injection time was adjusted from 10 μs to 25 μs, the output power changed from 143 W to 740 W. [ABSTRACT FROM AUTHOR]

Strong coupling in an inductive power transfer (IPT) system will lead to difficulties in power control and loss of soft switching conditions. This paper presents an IPT system that can decouple the converter from the resonant network. In the proposed system, the energy transmission process is divided into energy injection stage and free resonance stage. In the energy injection stage, the inductor is separated from the resonance network, and the power source injects energy into the inductor independently. In the free resonance stage, the inductor is connected to the resonance network for resonating. As a benefit from the decoupling of the converter from the resonance network, the proposed IPT system is characterized by easy power control and soft switching operation. A prototype was built for experiments. The experimental results show that with a supply voltage of 300 V, coupling factor of 0.2, and load resistance of 10 Ω, the output power can be controlled nearly linearly by the time of the energy injection stage in a range of 40–60 μs, and the system works under soft switching conditions. [ABSTRACT FROM AUTHOR]

This paper presents a study of a piezoelectric energy harvesting circuit based on low-power-consumption synchronized switch technology. The proposed circuit includes a parallel synchronized switch harvesting on inductor interface circuit (P-SSHI) and a step-down DC-DC converter. The synchronized switch technology is applied to increase the conversion efficiency of the circuit. The DC-DC converter is used to accomplish the impedance matching for different loads. A low-power-consumption microcontroller and discrete components are used to build the P-SSHI interface circuit. The study starts with theoretical analysis and simulations of the P-SSHI interface circuit. Simulations and experiments were conducted to validate the theoretical analysis. The experimental results show that the maximum energy harvested by the system with a P-SSHI interface circuit is 231 μW, which is 2.89 times that of a system without the P-SSHI scheme. The power consumption of the P-SSHI interface circuit can be as low as 10.6 μW. [ABSTRACT FROM AUTHOR]

In order to compensate the large leakage inductance and improve the power transmission capacity, capacitors are widely used in inductive power transfer (IPT) systems, which results in high voltage or current stresses in the resonant tanks and limits higher volt-ampere (VA) rating of the transfer power, especially in medium and low frequency applications. This paper presents a symmetrical half-bridge resonant converter (SHRC) for series-series/series compensated IPT systems with detailed analysis and design. It operates at a relatively low frequency of 12.5 kHz, suitable for IGBT applications. The theoretical analysis shows that, compared with full-bridge resonant converter (FRC) for IPT, the symmetrical half-bridge resonant converter achieves a higher efficiency. Simulation and a prototype of 1500 W power output were built to verify the theoretical analysis. The experimental results show that the power loss of SHRC is 39.7 W while that of FRC is 79.4 W, which is consistent with the theoretical analysis. The global efficiency of the IPT based on the proposed converter is 91.6%. [ABSTRACT FROM AUTHOR]

In a traditional inductive coupling power transfer (ICPT) system, the converter and the resonant network are strongly coupled. Since the coupling coefficient and the parameters of the resonant network usually vary, the resonant network easily detunes, and the system efficiency, power source capacity, power control, and soft switching conditions of the ICPT system are considerably affected. This paper presents an ICPT system based on a power converter decoupled from the resonant network. In the proposed system, the primary inductor is disconnected from the resonant network during the energy injection stage. After storing a certain amount of energy, the primary inductor is reconnects with the resonant network. Through this method, the converter can be decoupled from the resonant network, and the resonant network can be tuned under various coupling coefficients. Theoretical analysis was explored first. Simulations and experimental work are carried out to verify the theoretical analysis. The results show that the proposed ICPT system has the virtues of low power source capacity, independent power control, and soft switching operation under different coupling coefficients. [ABSTRACT FROM AUTHOR]

To develop a highly sensitive time-resolved fluorescence immunoassay (TRFIA) for the detection of serum matrix metalloproteinase-3 (MMP-3) and to assess MMP-3's clinical value in patients with colorectal cancer (CRC).st. MMP-3 levels were established using the double antibody sandwich technique. The MMP-3 TRFIA technique was developed and optimized, and its linearity, sensitivity, accuracy, specificity, and recovery were assessed. Then, serum concentrations in healthy individuals and patients with CRC were determined by MMP-3 TRFIA. The linear range of MMP-3 TRFIA was 0.73 – 500 ng/mL. MMP-3 TRFIA had an intra-batch precision range of 2.16%–7.10% percent and an inter-batch precision range of 3.99%–11.21%. MMP-3, tumor-associated trypsinogen 2, and AFP had no cross reaction.The recovery is between 90% and 110%, and had no serum interference. Patients with CRC had serum MMP-3 levels (73.95 ± 78.43 ng/mL) that were considerably higher than those of healthy individuals (21.45 ± 11.12 ng/mL), and those with metastasis had serum MMP-3 levels (95.89 ± 76.21 ng/mL) that were considerably higher than those of patients without metastasis (52.74 ± 47.25 ng/mL). A highly sensitive MMP-3 TRFIA assay was successfully developed, and serum MMP-3 may be associated with CRC invasion and metastasis. Therefore, MMP-3 can be used in the auxiliary diagnosis of CRC. • A time-resolved fluorescence immunoassay method for the detection of serum MMP-3 concentration was successfully established. • We found the levels of serum MMP-3 were higher in patients with colorectal cancer than healthy subjects. • Detection of serum MMP-3 concentration can distinguish patients with and without metastatic colorectal cancer. • MMP-3 can be used as an auxiliary detection marker for colorectal cancer. [ABSTRACT FROM AUTHOR]

This study aimed to establish a highly sensitive time-resolved fluorescence immunoassay (TRFIA) for the detection of serum lipoprotein-associated phospholipase A2 (Lp-PLA2) and evaluate the clinical application value of Lp-PLA2 in patients with breast cancer. The level of Lp-PLA2 was detected using the double-antibody sandwich method. First, the Lp-PLA2-TRFIA method was established, and the method was evaluated on the basis of linearity, sensitivity, precision, specificity, and recovery rate. Then, the fluorescence counts in serum of healthy subjects and patients with breast cancer were detected by Lp-PLA2-TRFIA, and the levels of Lp-PLA2 were calculated using a standard curve. Lp-PLA2-TRFIA had a wide linear range (43.48–2000 ng/mL). The intra-assay precisions of Lp-PLA2-TRFIA ranged from 2.66% to 4.84% (<10%), and the inter-assay precisions were between 5.39% and 6.95% (<15%). No cross-reaction was observed among Lp-PLA2, Tumor-associated trypsinogen-2, and T-cell immunoglobulin mucin 3. In addition, the recovery rates were between 90% and 100%. The serum Lp-PLA2 levels of patients with breast cancer were significantly higher than those of healthy subjects. We successfully established a highly sensitive Lp-PLA2-TRFIA method, and found serum Lp-PLA2 may be associated with dyslipidemia in breast cancer and could be used for auxiliary diagnose. [Display omitted] • We established Lp-PLA2-TRFIA method to detect serum Lp-PLA2 in the human and evaluated this method. • We found the levels of serum Lp-PLA2 were higher in patients with breast cancer than healthy subjects. • We found that patients with advanced breast cancer had sightly higher Lp-PLA2 levels than those with early breast cancer. • We used ROC curves to distinguish between patients with breast cancer and healthy subjects and found the AUC value was 0.904. [ABSTRACT FROM AUTHOR]

To establish a highly sensitive time-resolved fluorescence immunoassay of heparin-binding protein (HBP-TRFIA) and evaluate its application value for bacterial or fungal infections in tumor patients. Two types of HBP monoclonal specific antibodies against different epitopes of the antigen molecule were used as coating antibodies and Eu3+-labeled antibodies, respectively. The double-antibody sandwich method was used in establishing HBP-TRFIA, and the methodology was evaluated. The established HBP-TRFIA was used in detecting HBP concentration in the plasma samples of healthy individuals, patients with bacterial or fungal infections, and infected or uninfected patients with various types of tumors. The linear range of HBP-TRFIA was (0.11–530 ng/mL). Plasma HBP concentrations detected through HBP-TRFIA were consistent with the results of fluorescence quantitative immunochromatography (ρ = 0.964). The plasma HBP concentrations of infected tumor patients were significantly higher than those of uninfected tumor patients (P < 0.01). This study successfully established a highly sensitive HBP-TRFIA, which was highly comparable to commercially available fluorescent quantitative immunochromatographic kits and was able to facilitate the timely diagnosis of bacterial or fungal infections in patients with tumor. [Display omitted] • A highly sensitive time-resolved fluorescence immunoassay of heparin-binding protein is established. • HBP-TRFIA can facilitate timely diagnosis of bacterial or fungal infections in patients with tumor. • HBP-TRFIA helps research on the clinical value of HBP. [ABSTRACT FROM AUTHOR]

Choristoneura metasequoiacola Liu, 1983 is an important caterpillar species that specifically infests the leaves and branches of Metasequoia glyptostroboides Hu & W. C. Cheng 1948 with short larval infestations, long-term dormancy, and has a limited distribution in Lichuan, Hubei, China. The complete mitochondria genome of C. metasequoiacola was determined by using Illumina NovaSeq, and analyzed based on previously annotated sibling species. In total, we obtained mitochondria genome with 15,128 bp in length, circular in shape with a double-stranded closed ring structure, including 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes, and an AT-rich region. Of which the nucleotide composition was highly A + T biased, accounting for 81.98% of the whole mitogenome. Thirteen protein-coding genes (PCGs) were 11,142 bp; Twenty-two tRNA genes and AT-rich region were 1,472 and 199 bp, respectively. Phylogenetically, the relationship between Choristoneura spp. (containing C. metasequoiacola ) and Adoxophyes spp. was closer than any other two genera from Tortricidae, and the relationship between C. metasequoiacola and C.murinana was the closest among nine sibling species from that genus, which helps to explain species evolution within the family Tortricidae., Competing Interests: No potential conflict of interest was reported by the author(s)., (© 2023 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.)