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Three-phase wireless power transfer (WPT) systems have compact coil structures, canceled triplen harmonics, and less dc-link current ripple, which are suitable for wireless electric vehicle (EV) charging systems. Most three-phase WPT systems are based on two-level inverters. Alternately, three-level inverters have the potential to further promote the performance of EV chargers by reducing electromagnetic interference (EMI) and the voltage stress of power switches. However, the unbalance of the neutral point voltage is a problem for traditional three-level inverters. This paper proposes a three-level three-phase WPT system for EV wireless charging, which is based on a T-type neutral point clamp (TNPC) inverter. The modeling, coil structure, and switching pattern of the proposed system are analyzed in detail. Furthermore, a novel output regulation method based on vector control is proposed for the WPT system. Also, a neutral point voltage balance strategy is proposed to enhance the reliability of the three-level inverter. Both simulations and an experimental prototype based on SIC-MOSFET are given to verify the effectiveness of the proposed three-phase WPT system and control method.

This article presents a high-fidelity analytical solution and a fast integrated optimization method for vernier machines. First, a harmonic modeling method (HMM) is adopted to obtain the magnetic field distribution of vernier machines. Particularly, the stator teeth of vernier machines are divided into several blocks to take account of the local magnetic saturation of soft-magnetic material. Then, the electromagnetic parameters, such as the average torque, torque ripple, and efficiency, can be calculated via the analytical model. Next, the proposed harmonic model is combined with the nondominated sorting genetic algorithm II (NSGA-II) to determine a multiobjective optimal design for the studied vernier machine. This integrated optimization method can save computation time, because the data interaction process between the finite-element analysis (FEA) software and the optimization software is eliminated. Finally, the performances of the optimal case are verified by both FEA and experiments with the prototype.

We evaluated the safety and immunogenicity of four doses of 20 or 60 ��g, and the immunogenicity and compliance of the short-term vaccination regimen (0, 1, and 2 months) among patients receiving MMT. We conducted a randomized controlled trial among 303 patients receiving MMT who were randomized to receive 3 or 4 doses of 20 or 60 ��g of recombinant hepatitis B vaccine. At month 7, the seroconversion rates in both IM20 �� 4 and IM60 �� 4 groups were numerically higher than the IM20 �� 3 group (P > 0.05). The high-level responses and geometric mean concentration (GMC) of anti-HBs in both IM20 �� 4 and IM60 �� 4 groups were significantly higher than the IM20 �� 3 group (P 0.05). The completion rate of the short-term high-strength vaccination group was significantly higher than the standard vaccination group (P 0.05), with similar immunogenicity (P > 0.05). Both the high-strength and standard-strength four-dose hepatitis B vaccine regimens could improve the immune response for patients receiving MMT. The high-strength short-term vaccination regimen could improve compliance and attain comparable immunogenicity with the standard vaccination regimen. The high-strength short-term vaccination regimen is recommended and the fourth dose is encouraged for this population considering the compliance and immunogenicity. ClinicalTrials.gov (NCT03962816)

This article presents a new direct load voltage control method for electrolytic capacitorless wireless power transfer (WPT) system without dc/dc converter. In specific, the three-phase low-frequency ac to the high-frequency ac (HFac) converter is employed into the electrolytic capacitorless WPT system by using the bidirectional power switches. The HFac voltage is directly generated on the transmitting tank without using the electrolytic capacitor. Furthermore, in order to realize the discretionary and accurate load voltage control without dc/dc converter, the nine voltage vectors, including six effective voltage vectors and three zero voltage vectors, are selectively exported for the transmitting tank with different duty cycles. In addition, the unity power factor correction and direct load voltage control are both achieved only by transmitting side control. Meanwhile, theoretical analysis of double series-compensated transmitting network and duty cycles under resonant frequency calculation in microchip are demonstrated in detail. Finally, both simulation and experimental results are provided to verify the feasibility and correctness of the proposed system, which operates at 85 kHz with 90% efficiency and about 9% total harmonic distortion.

Transportation electrification has attracted much attention in modern society. Among all electrified transportation tools, electric vehicle (EV) is absolutely the one that has great potential to compete with and further take the place of traditional fossil fuel vehicles. This article is to outline and investigate advanced electric machines and their control strategies for EV applications. The key is not only to reveal new design ideas, topologies, structures, methodologies, control strategies, pros and cons, and foresight for advanced electric machines but also to fully integrate these ideas into practical EV applications. This critical review will clarify the development trends of electric machines and their controls.

The present study explored the effects of miR-152-mediated targeting of suppressor of cytokine signaling 3 (SOCS3) on hepatic insulin resistance (HIR) in mice with gestational diabetes mellitus (GDM). Healthy SPF C57BL/6J mice were selected to establish a GDM model.Mice were divided into seven groups as follows: Normal group, Model group, NC-mimic group, miR-152 mimic group, NC-pcDNA3.0 group, pcDNA3.0-SOCS group, and miR-152 mimic + pcDNA3.0-SOCS3 group. The relationship between miR-152 and SOCS3 expression was analyzed by a dual-luciferase reporter system. Islet cell morphology and expression of miR-152 and SOCS3 mRNA and protein in the islet tissue were detected by hematoxylin and eosin (HE) staining, reverse-transcription quantitative polymerase chain reaction (RT-qPCR), and western blot analysis. Fasting blood glucose (FBG) level was measured by a glucose meter while triglyceride (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and insulin levels were determined by an automatic biochemical analyzer. Insulin resistance index (HOMA-IR) was calculated by the formula FBG × FINS/22.5.The results showed that the levels of miR-152, SOCS3, FBG, fasting insulin (FINS), TG, and TC increased, and HDL-C content decreased in other groups as compared with those in the Normal group (all p0.05). Oral glucose tolerance test (OGTT), FBG, FINS, TG, TC, and HDL-C values showed an opposite trend in miR-152 mimic and pcDNA3.0-SOCS3 groups as compared with the Model group (all p0.05).miR-152 can inhibit HIR in GDM mice by downregulating the expression of SOCS3.

Monitoring power quality (PQ) in microgrids is gaining increasing attention in recent years due to the popularity of microgrids and PQ disturbances caused by renewable energies. Many techniques based on artificial neural networks (ANNs) are proposed for monitoring the PQ with no need to pre-set thresholds. However, the necessity of retraining the ANN is a big problem when the electrical parameters vary. This article proposes a new approach to detect and classify the PQ disturbances accurately in multimicrogrids based on electromagnetic sensing and portability-enhanced ANN. The proposed ANN-based approach avoids the retraining of weights, when the voltage, current, and frequency varies with microgrids. Two steps are critical for achieving the portability of the ANN in various microgrids, which are pre-normalization and using the same maximum and minimum feature vectors for feature matrix normalization. Meanwhile, the electromagnetic sensing facilitates non-intrusive monitoring and easy installation. The high accuracy of simulation and experimental results in various scenarios validate the effectiveness and efficiency of this portable and non-invasive approach for monitoring PQ in multimicrogrids without retraining ANN.

Objective The aim of this study was to assess the prevalence of thyroid autoimmunity in T2DM with NAFLD, furthermore explore the relationship between elevated TPOAb titer and the severity of NAFLD. Methods A total of 400 patients with T2DM were divided into two groups according to NAFLD. Thyroid function and other metabolic indicators were measured. Results There were more TPOAb-positive patients in both groups, and the prevalence of TPOAb positive was significantly different in two groups (17% vs 6.9%, p< 0.01). FT4 was significantly lower in patients with T2DM with NAFLD (median FT4 0.89 vs 1.08, p < 0.001), while TSH was increased (median TSH 2.85 vs 2.28, p < 0.05). In patients with T2DM with NAFLD, the proportion of women in the thyroid autoimmune-positive group was significantly higher than the negative (71.1% vs 46%, p < 0.01). Similarly, thyroid autoimmune-positive T2DM and NAFLD patients had lower FT4 levels (median FT4 0.59 vs 0.92, p < 0.001), higher TSH levels (median TSH 3.65 vs 2.67, p < 0.001), and much higher TPOAb/TGAb (median TPOAb/TGAb 6.8 vs 1.46, p < 0.001). The increase of TPOAb was significantly correlated with the severity of fatty liver. HbA1c, TC, TG, TSH, TPOAb/TGAb and severity of fatty liver were risk factors of thyroid autoimmunity. Conclusion Autoimmune thyroid disease is more common in patients with T2DM complicated with NAFLD. Elevated TPOAb titer is closely related to fatty liver, suggesting that elevated TPOAb titer is a predictor of autoimmune development in T2DM with NAFLD.

This article presents a wireless power transfer (WPT) system that can deliver power to multiple receivers concurrently with additional resonant frequencies and reduced power switches. It employs three-phase high-frequency inverter with delta-type transmitting tanks. In this way, this WPT system can transfer the power with different resonant frequencies to multiple receivers simultaneously. Compared with the typical multiple-frequency and multiple-receiver WPT system, the proposed WPT system can save considerable amount of power switches. In addition, three additional resonant frequencies can be obtained by setting up original equivalent resonant tank in transmitting side without any change. Three modes, namely the single frequency transmission, concurrent frequency transmission, and additional frequency transmission, are performed and analyzed in detail. Finally, a test rig is built up to verify the performances of six independent frequencies, six kinds of concurrent double frequencies, and one concurrent ternary frequency transmission, with one dealt type transmitting tank.

The increase of insulation thickness (IT) results in the decrease of the heat demand and heat medium temperature. A mathematical model on the optimum environmental insulation thickness (OEIT) for minimizing the annual total environmental impact was established based on the amount of energy and energy grade reduction. Besides, a case study was conducted based on a residential community with a combined heat and power (CHP)-based district heating system (DHS) in Tianjin, China. Moreover, the effect of IT on heat demand, heat medium temperature, exhaust heat, extracted heat, coal consumption, carbon dioxide (CO2) emissions and sulfur dioxide (SO2) emissions as well as the effect of three types of insulation materials (i.e., expanded polystyrene, rock wool and glass wool) on the OEIT and minimum annual total environmental impact were studied. The results reveal that the optimization model can be used to determine the OEIT. When the OEIT of expanded polystyrene, rock wool and glass wool is used, the annual total environmental impact can be reduced by 84.563%, 83.211%, and 86.104%, respectively. It can be found that glass wool is more beneficial to the environment compared with expanded polystyrene and rock wool.

This paper investigates two fundamental questions related to the social impact of high-speed rail (HSR): (1) does the development of HSR infrastructure lead to the exclusion of certain social groups? and (2) what factors exclude certain users from using HSR? Based on a comprehensive survey of 4,924 passengers who chose conventional rail services in China, both binary and multinomial logit analyses were conducted to examine to what extent the mode choice of passengers who departed from Chongqing was affected by various factors, including socioeconomic and train service conditions. The analyses reveal that factors such as fare, travel habits, trip distance, and onboard amenities play significant roles in whether passengers choose conventional rail over HSR. Conversely, the study shows that lower incomes and education levels are associated with higher odds of choosing conventional trains over HSR by 24.1% and 25.3%, respectively. Furthermore, the study shows that the preference of conventional rail to HSR varies among different regions in China. In particular, people were found to prefer less to choose conventional trains in the west and central regions than the east region when the HSR service becomes available. Such a pattern suggests that HSR as a new mode of intercity travel, has become a preferred mode for many people, even for those in the less developed regions in China. However, some passengers from less developed western provinces were also found to have a stronger sense of being excluded from using HSR, given the concerns of high fares and personal perception of cities that the system serves. Overall, this study provides important implications for planning and policy-making to achieve sustainable operations and the development of the passenger rail system.

Background Clinical research has demonstrated that brain reserve (BR) could exert positive effects on cognition for patients with Alzheimer's disease (AD) and mild cognitive impairment (MCI). However, the effects of BR on cognition in individuals with subjective cognitive decline (SCD) are not clear. Objective To examine cross-sectional effects of BR on cognition in SCD populations. Methods One hundred forty-nine subjects were studied from the Sino Longitudinal Study on Cognitive Decline (SILCODE) study. Head circumference was used as a proxy of BR. Cognition was assessed across four domains (memory, executive, language, and general cognitive functions). Multiple linear regression models were conducted to examine effects of BR on cognitive scores. Furthermore, we addressed the question that whether the degree of self-perception of cognitive decline modified the effect of BR on cognitive performance in SCD subjects. Results We found a positive effect of BR on language cognition in subjects with SCD. Furthermore, the positive effect of BR on language cognition survived in SCD participants with a low degree of self-perception of cognitive decline while disappeared in SCD participants with a high degree of self-perception of cognitive decline. Conclusion This study suggests that BR has the potential to delay or slow down cognitive decline in SCD individuals, especially for mild SCD.

This paper proposes an effective charging-torque elimination method for six-phase integrated on-board electric vehicle (EV) chargers. The integrated EV charger is derived from the power inverter, motor windings, sensors, and microchips, which can significantly reduce the system cost and volume. In fact, the charging electromagnetic torque is inevitable to produce, since the alternating currents flow through the motor windings. This is due to the motor windings serving as the filtering inductors of the rectifier for the on-board charger. In order to keep the vehicle standstill during the charging process, a universal expression of charging torque is derived and analyzed, which is according to magnetic co-energy approach. All possible charging torque elimination positions are presented with a numerical method. Moreover, the unity power factor and zero sequence current control are executed during the EV charging process. Finally, the proposed charging torque elimination method is verified by both simulation and experimentation. The results prove the validity of the proposed charging-torque elimination method for six-phase permanent magnet synchronous machine.

The permanent-magnet Vernier (PMV) machine has been welcomed for direct-drive applications recently. Also, the fault tolerance is critical for special machine design in hostile conditions. This article proposes an efficient PMV machine with the modular winding configuration, which takes the fault-tolerant capability into account, especially the open-circuit fault. With the modular winding design, the better isolation between phases and modules can be obtained instead of dividing the stator core into segments. Meanwhile, the high efficiency needs to be guaranteed under both normal and partial-module operations. Therefore, the machine design, basic characteristics, and the fault-tolerant operation are performed and verified. Finally, the efficiency performances under normal and modular operations are analyzed and compared, which demonstrates the validity of the proposed idea and relevant considerations.

Flux-modulated double-rotor (FMDR) machine topology has recently attracted much attention, particularly for the hybrid electric vehicle (HEV) propulsion. To maintain the driving stability and safety of the vehicle, the analysis of the magnetic force and the evaluation of the vibration performance for such kind of machine are indispensable. However, for the FMDR machine with the magnetic-gearing (MG) effect, there are at least two rotating magnetic fields with different speeds and frequencies. This leads to the complicated time harmonics of the radial force density. Actually, the publications on the FMDR machine hardly take into account the magnetic force or vibration characteristics. In this article, the sources, variations, and different kinds of magnetic forces are thoroughly investigated for a proposed FMDR machine. First, the machine topology and operation principle are introduced. Second, the theoretical analysis of the flux density and radial force density is implemented from the harmonic point of view, which is followed by the finite-element simulation, comparison, and validation. Also, an effective solution is proposed and discussed for the problem of different mixed electrical frequencies in the machine. Finally, the distributions of different kinds of magnetic forces appearing in the FMDR machine are concluded.

In this paper, a novel kind of wireless motors, namely, the LCC -compensated wireless switched reluctance motor, is proposed and implemented. The definite advantages are that there is no power converter at the motor side and particularly no switched-capacitor array at the transmitter side to realize the multiple-frequency operation. The key is to develop an LCC compensation involving an inductor and two capacitors (the so-called LCC ) for a multiple-frequency wireless power transfer system. As a result, only one transmitter is needed to targetedly feed three receivers, which directly energize the three phase windings of the motor. Particularly, there is no need to control switched capacitors to change the resonant frequency of the transmitter. Meanwhile, the burst firing control method is employed to realize the speed control. Both calculation and experimental results are presented to validate the feasibility of the proposed system. In the system prototype, the transmission distance can reach up to 150 mm and the transmission efficiency can be achieved up to 80%.

Smart living is a trending and connected lifestyle that envisions efficient and sustainable energy utilization, stable and reliable power supply, intelligent and coordinated transportation and mobility, and personalized and cost-effective healthcare. Its realization needs the Internet of Things (IoT). IoT is a compelling platform connecting trillions of sensors and collecting data for connectivity and analytics. It is more advanced than traditional monitoring systems where limited sensors and wired communication can merely collect fragmented data in the application domains. Spintronic sensors with the superb measuring ability and multiple unique advantages can be one of the critical sensing devices supporting the IoT and enabling smart living. In this paper, we review successful applications of individual spintronic sensors in electrical current sensing, transmission and distribution lines monitoring, vehicle detection, and biodetection that can help to fulfill the promises of smart living in energy management, power delivery, transport, and healthcare. The wireless spintronic sensor networks (WSSNs) working at the massive interconnected network level are proposed and illustrated to provide pervasive monitoring systems, which facilitate the intelligent surveillance and management over building, power grid, transport, and healthcare. The database of collected information will be of great use to policy making in public services and city planning. This paper provides insights for realizing smart living through the integration of IoT with spintronic sensor technology.

Stimulus-responsive hydrogels are significantly programmable materials that show potential applications in the field of biomedicine and the environment. Ultrasound as a stimulus can induce the formation of hydrogels, which exhibit the superior performance of different structures. In this study, we reported an ultrasound-induced supramolecular hydrogel based on aspartic acid derivative N,N′-diaspartate-3,4,9,10-perylene tetracarboxylic acid imide, showing superior performance in drug release. The results show that the driving force of this ultrasonic induced hydrogel could be attributed to hydrogen bonding and π-π interaction. The rheological and cytotoxicity test illustrate excellent mechanical properties and biocompatibility of the hydrogel. The anti-Schistosoma japonicum cercariae (CC) drug release results show large drug loadings (500 mg/ml) and long-term release (15 days) of this hydrogel. This study demonstrates that this hydrogel may serve as a slow-release platform for anti-CC.

Background Clinically, Yiqi Dingxuan Yin promotes nerve function recovery and improves nerve function defect symptoms; however, the underlying molecular pathways remain unknown. In this study, we established a rat model of cerebral ischaemia induced by middle cerebral artery occlusion (MCAO). The effects of Yiqi Dingxuan Yin on the neurological function and local neuron morphology were compared with those of butylphthalide, which is used to treat ischemic stroke, and the possible mechanisms of action were explored. Methods Of 97 healthy adult male Sprague‒Dawley rats, 20 were randomly assigned to the sham operation group. The remaining rats underwent MCAO. Model generation was successful in 60 rats, which were randomly divided into a model group, butylphthalide group, and Yiqi Dingxuan Yin group (n = 20/group) administered distilled water, butylphthalide capsule, and Yiqi Dingxuan Yin, respectively. Zea-Longa scores were used to assess the neurological function of the rats at 1, 3, 7, and 14 days. Haematoxylin and eosin staining of brain sections was used to observe morphological changes in the rat hippocampus. Apoptosis of nerve cells was detected using TUNEL staining. The expression levels of erythropoietin/erythropoietin receptor (EPO/EPOR), vascular endothelial growth factor (VEGF), and brain-derived neurotrophic factor/tyrosine receptor kinase B (BDNF/TrkB) protein in the ischaemic brain tissue were detected using immunohistochemistry. Results The apoptosis rate, and EPO/EPOR, VEGF, and BDNF/TrkB expression levels were higher in the model group than in the sham operation group (P P P

Purpose To systematically evaluate the effects of Electronic health (eHealth) interventions on fatigue, pain, and sleep disorders in cancer survivors. Design A systematic review and meta-analysis was conducted. Methods Relevant studies were searched from five databases (MEDLINE, Embase, the Cochrane Central Register of Controlled trials, CINAHL, and PsycINFO). The comprehensive literature search was done in December 2020. Only randomized controlled trials (RCTs) that examined the effects of eHealth interventions among cancer survivors were included. Findings Twenty-five RCTs were included. The meta-analysis showed that eHealth interventions had a positive impact on pain interference (SMD = -0.37, 95% CI: -0.54 to -0.20, p = 0.0001) and sleep disorders (SMD = -0.43, 95% CI: -0.77 to -0.08, p = 0.02) but not on pain severity or fatigue in cancer survivors. The sensitivity and subgroup analyses indicated that the pooled results were robust and reliable. Conclusion eHealth interventions are effective in improving pain interference and sleep disorders in cancer survivors. Additional high-quality RCTs are needed to test the effectiveness of eHealth interventions on fatigue, pain, and sleep disorders in cancer survivors. Clinical relevance This systematic review and meta-analysis provides evidence to offer effective and sustainable eHealth care for symptom management among cancer survivors.

BackgroundThere is a huge controversy about whether xenograft or allograft in the “immune-privileged” brain needs immunosuppression. In animal studies, the prevailing sophisticated use of immunosuppression or immunodeficient animal is detrimental for the recipients, which results in a short lifespan of animals, confounds functional behavioral readout of the graft benefits, and discourages long-term follow-up.MethodsNeuron-restricted neural progenitor cells (NPCs) were derived from human embryonic stem cells (ESCs, including H1, its gene-modified cell lines for better visualization, and HN4), propagated for different passages, and then transplanted into the brain of immunocompetent rats without immunosuppressants. The graft survivals, their cell fates, and HLA expression levels were examined over time (up to 4 months after transplantation). We compared the survival capability of NPCs from different passages and in different transplantation sites (intra-parenchyma vs. para- and intra-cerebroventricle). The host responses to the grafts were also investigated.ResultsOur results show that human ESC-derived neuron-restricted NPCs survive extendedly in adult rat brain parenchyma with no need of immunosuppression whereas a late-onset graft rejection seems inevitable. Both donor HLA antigens and host MHC-II expression level remain relatively low with little change over time and cannot predict the late-onset rejection. The intra-/para-cerebroventricular human grafts are more vulnerable to the immune attack than the intrastriatal counterparts. Prevention of graft hyperplasia by using hypoproliferative late passaged human NPCs further significantly extends the graft survival time. Our new data also shows that a subpopulation of host microglia upregulate MHC-II expression in response to the human graft, but fail to present the human antigen to the host immune system, suggestive of the immune-isolation role of the blood–brain barrier (BBB).ConclusionsThe present study confirms the “immune privilege” of the brain parenchyma and, more importantly, unveils that choosing hypoproliferative NPCs for transplantation can benefit graft outcome in terms of both lower tumor-genic risk and the prolonged survival time without immunosuppression.

This paper presents a safe charging operation for the integrated on-board electric vehicle (EV) charging system, where the power electronic components are reconfigured from the propulsive system. First, the rotational movement is detected and analyzed, when the motor windings are reutilized as the dc–dc inductors. Then the safe charging operation is investigated, which is based on the analysis of the charging torque and the ripple currents. Moreover, a new control strategy is presented with the purpose of the safe operation and smoothing reactor during the EV charging process. Finally, both simulation and experimentation are carried out to verify the safe charging operation. The results prove the feasibility and validity of the proposed safe charging operation for on-board charger with the three-phase interior permanent-magnet motor.

Fast online detection of inter-turn short-circuit faults for permanent magnet synchronous machines (PMSMs) is a challenging task. Previous attempts based on phase currents or back EMF monitoring lack the capability to accurately locate the inter-turn short-circuit faults in stator windings. This paper proposed a new approach to online inter-turn short-circuit fault detection for PMSMs by means of sensing the external stray magnetic field outside the motor stator yoke. The stray magnetic field provides the information about the phase currents as well as the status of stator windings and thus, the location of inter-turn short-circuit fault can be detected accordingly. In this paper, the inter-turn short-circuit model and the stray magnetic flux model for PMSMs were theoretically analyzed. Both FEM simulations and experiments have been presented to validate the effectiveness of the proposed approach. A sensor array composed of 24 sensitive tunneling magnetoresistive (TMR) sensor units was employed to measure the stray magnetic field distribution outside the PMSM stator yoke. The experimental results show that both the location and severity of the inter-turn short-circuit fault in PMSMs were effectively detected using the proposed approach.

Electric continuously variable transmission (e-CVT) device is a key component in hybrid electric vehicles (HEVs), which serves to perform the energy transmission among the initial combustion engine, battery, and output shaft. This paper presents a novel consequent-pole PM magnetic-geared double-rotor machine (CPDRM) that utilizes the magnetic gearing effect to transmit the power with a high efficiency. The artistry of CPDRM is to insert a dc winding within the center of the stator on the circumferential direction. Therefore, the machine can extend the constant-power region by changing the current direction and amplitude of dc windings. Meanwhile, the flux density within the air gap is changed accordingly. Then, the working principle of CPDRM and the flux change process are illustrated by employing the magnetic circuit method. Finally, a finite-element method model is constructed to verify the performances of the CPDRM under different operating modes. The result shows that the proposed machine has an excellent flux-weakening ability, and it can serve as a suitable candidate as an e-CVT component for HEVs.

Power allocation is important for dynamic dual-pickup wireless charging system of electric vehicles (EVs). The existing power allocation methods of wireless power transfer technology mainly focus on allocating the power to loads according to the needs with different resonant frequencies. However, the issues of inaccuracy and low power are still not well solved by the existing methods. In addition, the control strategies of existing methods are complex and difficult to implement in practical situations. In this paper, a new power allocation method is proposed, which can dynamically and precisely allocate power to loads. Moreover, the dynamic mutual inductance estimation and the power ratio change between loads are also investigated. In addition, this method has no need to use additional circuits for the receiving coil. Thus, it is convenient to implement in the dual-pickup wireless charging system of EVs. Experimental results have well verified the correctness of the proposed dynamic mutual inductance estimation and power allocation method.

The wirelessly transferred power as well as charging efficiency will significantly drop due to the large misalignment between the transmitting coil and receiving coil for roadway electric vehicles (EVs). A low-cost and reliable misalignment-tolerant wireless charging technique is indispensable for the rapid commercialization of wireless EV charging. This paper presents a technique to achieve the misalignment-tolerant wireless charging for the dynamic wireless charging (DWC) system by means of a tunneling magnetoresistive (TMR) sensor array as well as the easy-to-fabricate receiving coils. The TMR sensor array provides the coil-misalignment position by measuring the magnetic field component generated from the transmitting coil. The corresponding receiving coils are selected to be in resonance according to the measured coil-misalignment positions. In this paper, a sensor array composed of 29 uniaxial TMR sensors was utilized to measure the magnetic field component. This effectiveness of the proposed technique has been validated by both the finite-element method (FEM) simulations and laboratory experiments. The experimental results demonstrated that the proposed misalignment-tolerant wireless charging system can operate in a relatively wide misalignment range of ±120 mm with charging efficiency higher than 76.2%.

This paper presents a new effective sandwiched wireless power transfer (WPT) system, which is adopted to recharge the battery of a micro medical robotics for a cardiac pacemaker. The key of the design is to use the distinct sandwiched topology in both the transmitter and receiver coils, whose operating frequency of 160 kHz is significantly lower than the reported WPT system up to megahertz. Furthermore, the implantable receiver adopts the bilateral coil design, which can harness more power within a limited size. Meanwhile, with the sandwiched transmitting coils, the proposed design achieves the high feasibility and flexibility of the controllable distance for different kinds of micro medical robotics in patients. As a result, the proposed system can provide the power as high as 5 W and the transmission efficiency up to 88%. Finally, the corresponding theoretical analysis, simulation, and experimentation are carried out to prove the validity of the proposed sandwiched medical WPT system for the implantable device in the patient body.

In this paper, a wireless ballastless lighting system for fluorescent lamps is proposed and implement-ted. The key is to utilize magnetic resonant coupling to achieve wireless power transfer (WPT) while igniting the fluorescent lamp without using any magnetic or electronic ballast. Meanwhile, series-parallel compensation is identified to be more suitable for this WPT system. Also, burst firing control is utilized to achieve efficient light dimming. In order to achieve the fully wireless feature, remote lighting control via Bluetooth is realized by a smart phone. As an example, an experimental setup, which can light up an 8 W fluorescent lamp with illuminance of 2330 lx, has been designed and developed. In particular, it can achieve the transmission efficiency of 57% and the operating frequency of 51 kHz, with distance up to 56 cm. Both theoretical analyses and experimental results are given to validate the feasibility and flexibility of the proposed system.

A cost-effective technology to monitor the charging performance and detect the coil misalignment and foreign metal objects is indispensable to the commercialization of wireless power transfer on electric vehicle (EV) charging. This paper presents a multi-purpose tunneling magnetoresistive (TMR) sensor matrix, which can monitor the charging performance as well as detect both the coil misalignment and metal objects for wireless EV charging. The magnetic field distribution between coils is measured by the TMR sensor matrix to provide the critical information about charging performance, coil misalignment position, and the existence of metal objects. The mutual inductance and charging power are derived from the measured z-components of the magnetic flux densities. Lateral misalignment position is determined by the symmetry coefficients of the time-varying magnetic field distribution in the range of ±150 mm. Metal objects are detected by the measured magnetic field offsets. In this paper, both 3D finite-element-method modeling and experimental results were presented to demonstrate the effectiveness of the proposed approach. A $14 \times 14$ TMR sensor matrix with high sensitivity of 80 mV/V/mT was designed and implemented to measure the magnetic field distribution in order to demonstrate the technology.

The commercialization and wide application of electric vehicles (EVs) rely on the development of EV charging infrastructure and its coordinated operation in the electric power grid with renewable energy sources. As the EV aggregator is introduced as intermediate control entity to form a multi-layer control framework, the optimal configuration of EV aggregator and the charging power regulation are closely related to each other. This paper proposes an integrated optimization to solve the mixed configuration and operation problem of EV aggregator. A hybrid optimization algorithm based on partial swarm optimization (PSO) and sequential quadratic programming (SQP) is formulated to find the best solution for the location and size of EV aggregator in the distribution network and the charging scheduling of each individual EV. The master problem in the coupled optimization algorithm is to calculate the optimal configuration of the EV aggregator based on the estimation of the EV charging load, and based on the setting of EV aggregator the subproblem is to obtain the charging plan for individual EV under the day-ahead optimal dispatching of charging demand in the distribution grid. Finally, 123-bus distribution system is adopted to analyze the characteristics of the proposed model for concurrent optimization of EV aggregator and its operation in the test distribution network. The simulation results validate the hybrid optimization algorithm in integrated configuration and operation of EV charging infrastructure.

In this paper, a new class of wireless secondary converterless switched reluctance motor (WSC-SRM) drives is proposed and implemented. The key is to develop a unique wireless power transfer (WPT) system to directly drive the SRM without involving any power converter at the motor side. This is particularly essential to enable the WSC-SRM to work in an isolated environment without maintenance. Based on the selective WPT, the phase windings of the SRM can be properly energized by the same transmitter that adopts a newly developed compound structure. Meanwhile, signal duty ratio control of the transmitter is employed to achieve the speed control of the WSC-SRM. Both simulation and experimental results are given to validate the feasibility of the proposed system. For exemplification, a prototype is designed and constructed, which can provide WPT up to 150-mm transmission distance and achieve up to 72.8% transmission efficiency.

A facile and mild dip-coating method of fabricating superhydrophobic coating for cotton textiles was proposed. Cotton fabric was treated with TiO2 sol prepared under mild conditions and subsequentl...

With the increasing concerns on more electricity or full electricity for modern energy conversion systems, the key component of electric machine, has been paid more and more attention for the development of the new topologies and advanced drives. In the meantime, the emerging machines and drives show the increasing merits for the modern industrial needs. This paper investigates the latest developments and challenges of electric machines and drives. The key is to discuss and explore the machine topologies, structures, characteristics, operation principles, control strategies, and new applications. Thus, the developing trends and opportunities of the new electric machines and drives can be revealed for modern potential applications.

This paper presents an approach to detect the lateral coil misalignment for the dynamic wireless charging system using a tunneling magnetoresistive (TMR) sensor array. The component of the magnetic field generated from the transmitting coil can directly provide the information of the coil misalignment between transmitting and receiving coils. A sensor array composed of 15 uniaxial TMR sensors was implemented to measure the vector magnetic field for detecting the coil misalignment. Both 3-D finite-element method modeling and experimental results over a relatively large misalignment range were presented to substantiate the effectiveness and feasibility of the proposed approach.

Background There is an emerging literature on the mental health of both pre- and post-partum mothers during the coronavirus disease 2019 (COVID-19) pandemic. Methods As of April 1, 2020, 23 mothers confirmed with COVID-19, 15 mothers suspected with COVID-19 but with negative polymerase chain reaction tests, and 33 mothers without COVID-19 (Control Group) were recruited for a study from Hubei Province in China. The Maternal Postnatal Attachment Scale (MPAS), the Zung Self-rating Anxiety Scale, and the Zung Self-rating Depression Scale were applied to investigate the attachment of mothers to their neonates and the postpartum mental health of mothers within the first 3 months after delivery (between 20 to 89 days). Results The period of mother-child separation among the confirmed group (33.9±20.9 days) was significantly longer than that of suspected group (16.7±12.2 days) and control group (10.7±8.4 days). The total score of the MPAS in mothers confirmed with COVID-19 (45.5±4.2) was significantly lower (indicating less mother-child attachment) than that in the suspected (50.5±4.7) and control (48.8±4.6) groups. A negative correlation was noted between the mother-child separation time and the MPAS scores, including the subscale scores of attachment (MPAS acore: Spearman's ρ =-0.33, 95% CI: -0.095 to -0.538, P=0.005; Subscale score of attachment: Spearman's ρ =-0.40, 95% CI: -0.163 to -0.592, P=0.001). The incidence of postpartum anxiety in the confirmed, suspected and control groups was 4.3%, 6.7% and 12.1%, respectively; and the incidence of postpartum depression was 39.1%, 33.3% and 30.3%, respectively. No significant difference was found with regards to maternal postpartum anxiety and depression among the three groups. Conclusions Decreased mother-child attachment found among mothers confirmed with COVID-19, indicates that further intervention is needed to ensure mother-child interaction to appropriately develop attachment. Mother-child attachment experienced disruption due to prolonged mother-child separation necessitated by the COVID-19 management protocol, which needs to be revised to reduce prolonged mother-child separation. Additionally, mothers with and without COVID-19 suffered a high incidence of depression, which warrants further mental health investment for pregnant mothers during the COVID-19 pandemic.

The aim of this study was to determine a pattern associated with longitudinal changes of β-amyloid (Aβ) deposition during cognitively normal(CN) healthy aging. We used 18F-florbetapir (AV-45) PET images of the brains of 207 cognitively normal subjects (CN1), obtained through the Alzheimer's Disease Neuroimaging Initiative (ADNI), to identify the healthy aging pattern and 76 cognitively normal healthy subjects (CN2), obtained through the Xuanwu Hospital of Capital Medical University, Beijing, China, to verify it. A voxel-based correlation analysis of standardized uptake value ratio (SUVR) map image and age was conducted using the DPABI (Data Processing & Analysis of Brain Imaging) software to identify the pattern. The sum of squares due to errors (SSE), R-square (R2) and the root-mean-square error (RMSE) were calculated to assess the quality of curve fitting. Among them, R2 was proposed as the coherence coefficient, which was as an index to assess the correlation between SUVR value of the pattern and subjects' age. The pattern characterized by age-associated longitudinal changes of Aβ deposition was mainly distributed in the right middle and inferior temporal gyrus, the right temporal pole: middle temporal gyrus, the right inferior occipital gyrus, the right inferior frontal gyrus (triangular portion), and the right precentral gyrus. There were a significant positive correlation between the SUVR value of the pattern and age for each CN group (CN1: R2 = 0.120, p < 0.001 for quadratic model; CN2: R2 = 0.152, p = 0.002 for quadratic model). These findings suggest a pattern of changes in Aβ deposition that can be used to distinguish physiological changes from pathophysiological changes, constituting a new method for elucidating the neuropathological mechanism of Alzheimer's disease.

Taking a barber shop in Dezhou City of Shandong Province as an example, this paper calculates the required heat by using 300 liters of 40 °C hot water every day, introduces the working principle and system characteristics of electric water heater and solar water heater, selects the mainstream products in the market, and calculates the use cost. The comparison shows that the price of electric water heater is low, but the annual cost is high; the price of solar water heater is high, but the annual cost is low.

The multi-objective optimization of the hybrid biomass gasification-based combined cooling, heating and power (BGBCCHP) system with respects to economy, energy and environment were realized. A feasibility study on adding the electric chiller (EC) and heat storage tank (HST) to the system was performed. An improving following hybrid electric-thermal load (IFHL) strategy was proposed. The configuration of system operated under three operating strategies (following thermal load (FTL), following electric load (FEL) and IFHL) and four kinds of biomass raw materials (corn straw (CS), wood pellet (WP), wheat straw (WS) and rice straw (RS)) were used in the optimization. Results show that CS is more helpful to improve economic, environmental and comprehensive performance, while WP is more helpful to improve energetic performance. The capacity of the EC of the system optimized from energetic perspective is larger than that of the system optimized from other perspectives. HST is recommended to add to the system under FEL. IFHL and FEL yield the best and worst system performance, respectively. Sensitivity analysis indicates that gasification efficiency has the greatest impact on the system performance. As for the feed-in tariff policy, the equipment capacity and economic performance of the system are not affected by incentive coefficient.

Researchers have recently attached more attention on permanent magnet brushless AC motors for electrified propulsion. Considering the further improvement of torque density, this paper proposes a novel pulse width modulation (PWM) magnet array and quantitatively analyzes the magnetic field with different magnet configurations. It is a good potential for reducing the magnet volume. Based on a slotless motor design which eliminates the influence of additional harmonic sources except for that from magnets, investigations on motor performance with proposed magnet array are made. Also, the improvement of torque density is discussed and verified.

“Big data” has become a well-deserved focus in the industry in the past year. Especially with the development of new SNS network, the surge of video traffic and the emergence of photo sharing needs, big data grows more rapidly in the fertile soil. The era of big data has come, we can use big data for all aspects of analysis, so as to provide us with more abundant information resources. This paper takes Chinese drama as the research object and analyzes the characteristics of Chinese drama with big data analysis method, so as to summarize the characteristics of Chinese drama and contribute to the development of Chinese drama. The big data analysis method adopted in this paper is to use crawler software and SPSS Modeler to conduct data mining and modeling and obtain the corresponding feature word cloud. The research of this paper shows that the unique performance style and expression technique of Chinese drama make the characteristics of drama obvious and have the characteristics of generality, freehand brushwork and theatricality. According to these characteristics, relevant laws and regulations can be issued at the national or government level to promote the development of Chinese drama and enable the broad masses of people to have a deeper understanding of Chinese drama.

The effects of thyrotropin (TSH) suppressive therapy on autonomic regulation and ventricular repolarization in patients with differentiated thyroid cancer (DTC) have not been elucidated. The aim of present study was to evaluate variation in heart rate variability (HRV) and QT dispersion after TSH suppressive therapy in patients with DTC. Cases, defined as 271 patients with DTC within 1 year of exogenous levothyroxine, and all patients underwent a full history, physical examination, including standard 12 lead electrocardiogram (ECG), and 24 h ambulatory ECG monitoring (Holter) with normal free thyroxine (FT4) and free triiodothyronine (FT3) with levothyroxine. To evaluate effects of TSH suppressive therapy on HRV and QT dispersion, patients were divided into three groups according to different levels of TSH: TSH

Subjective cognitive decline (SCD) is the preclinical stage of Alzheimer's disease (AD). Abnormal brain glucose metabolism and Aβ depositions can be observed in SCD subjects. Nevertheless, there was not cognitive impaired performance in standardized neuropsychological in these subjects. Cognitive reserve (CR) could be the reason to explain this phenomenon. However, correspondence between CR and SCD was still uncleared. In this study, we attained 74 subjects underwent 18FFDG PET scans (SCD1 group) and 38 patients underwent 18FAV45 PET scans (SCD2 group) from Xuanwu Hospital, Beijing, China. First, SCD1 group was divided into SCD1H (high CR, n=33, educational years>12) and SCD1L (low CR, n=41, educational years 12) and SCD2L (low CR, n=21, educational years

Many studies have explored the association between neuropathy and osteoporosis in patients with diabetes mellitus. However, the results still remain inconsistent and controversial. We aimed to estimate the association between diabetic neuropathy and osteoporosis. Databases, including PubMed, Embase, Web of Science, the Cochrane library, Chinese Biomedical Literature Database (CBM), and Wanfang, were screened from inception to 30 March 2020. Studies were selected and data were extracted by two independent reviewers. Study characteristics and quality sections were reviewed independently. Pooled ORs and 95% CIs were calculated using random effects model when evidence of heterogeneity was present; otherwise, fixed effects model was used. Meta-regression and subgroup analyses were performed to explore the source of heterogeneity. Sensitivity analysis and publication bias were also tested. A total of 11 studies with 27,585 participants were included in this analysis which indicated that there was an increased odd between diabetic neuropathy and osteoporosis (overall OR 2.20, 95% CI 1.71–2.83). In the subgroup analyses and meta-regression, diabetic neuropathy has no significant difference in osteoporosis or fracture (p = 0.532). And osteoporosis also has no significant difference in type 1 or type 2 diabetic neuropathy (p = 0.668). This meta-analysis suggests that patients with diabetic neuropathy have a significantly increased chance of developing osteoporosis, even fragility fracture. The clinicians should pay more attention to the patients with diabetic neuropathy. Further studies were still needed to explore the confounding factors among studies and to elucidate the underlying biological mechanisms.

The aim of this study is to explore functional and structural properties of abnormal brain networks associated with Parkinson’s disease (PD). 18F-Fluorodeoxyglucose positron emission tomography (18F-FDG PET) and T1-weighted magnetic resonance imaging from 20 patients with moderate-stage PD and 20 age-matched healthy controls were acquired to identify disease-related patterns in functional and structural networks. Dual-modal images from another prospective subject of 15 PD patients were used as the validation group. Scaled Subprofile Modeling based on principal component analysis method was applied to determine disease-related patterns in both modalities, and brain connectome analysis based on graph theory was applied to verify these patterns. The results showed that the expressions of the metabolic and structural patterns in PD patients were significantly higher than healthy controls (PD1-HC, p = 0.0039, p = 0.0058; PD2-HC, p < 0.001, p = 0.044). The metabolic pattern was characterized by relative increased metabolic activity in pallidothalamic, pons, putamen, and cerebellum, associated with metabolic decreased in parietal–occipital areas. The structural pattern was characterized by relative decreased gray matter (GM) volume in pons, transverse temporal gyrus, left cuneus, right superior occipital gyrus, and right superior parietal lobule, associated with preservation in GM volume in pallidum and putamen. In addition, both patterns were verified in the connectome analysis. The findings suggest that significant overlaps between metabolic and structural patterns provide new evidence for elucidating the neuropathological mechanisms of PD.