Design and Performance Analysis of Permanent Magnet Claw Pole Machine with Hybrid Cores

Permanent magnet claw pole machine(PMCPM) is a special kind of transverse flux permanent magnet machine. Compared with other electrical machines, it has the advantages of high torque density and high efficiency for high speed operation. However, because of its complex irregular structure, the manufacturing process using silicon sheets is complicated. Soft magnetic composite material(SMC) is manufactured by powder metallurgy technology, which can produce various shapes of stator core structures, so it is easier to produce various irregular shapes of the stator core. However, the raw SMC material is relatively expensive, and the mechanical strength of SMC is weak. In this paper, a PMCPM with hybrid cores is proposed. With the adoption of hybrid silicon sheet-SMC cores and amorphous alloy-SMC cores, the torque ability of PMCPM can be improved greatly and it can have higher efficiency for more wide operation frequency. Meanwhile, its mechanical strength has been improved and it can be designed for high torque direct drive applications as it is a modular machine. Furthermore, three methods are proposed to reduce the additional eddy current loss which resulted from the employment of hybrid cores in PMCPM.

Danggui Niantong decoction ameliorates joint inflammation and cardiopulmonary injury in TNF-Tg mice

Objective:Rheumatoid arthritis(RA)is a common autoimmune disease characterized by multiple joint lesions and systemic complications.Danggui Niantong decoction(DGNTT)has been clinically used for RA treatment;however,its beneficial effect on cardiopulmonary complications has not been reported.Methods:Female tumor necrosis factor-transgenic(TNF-Tg)mice were used to evaluate the therapeutic effects of DGNTT on arthritis and cardiopulmonary complications.Methotrexate(MTX)served as a positive control.Histopathological assessment of the joint sections was performed using hematoxylin and eosin(HE),Alcian Blue/Orange G,and tartrate-resistant acid phosphatase staining.Bone mass was assessed by micro-computed tomography,inflammatory infiltrates in the heart and lungs were evaluated by HE staining,cardiopulmonary fibrotic injury was identified by Masson’s trichrome staining,and hypertrophy of mouse cardiomyocytes was measured by wheat germ agglutinin(WGA)staining.Results:DGNTT mitigated the inflammation of the ankle joint synovium,decreased the number of osteoclasts,and increased the area of cartilage and bone mass in TNF-Tg mice.In addition,DGNTT decreased the infiltration of inflammatory cells into the lung and heart tissues,accompanied by a reduction in cardiopulmonary fibrosis and myocardial cell hypertrophy in TNF-Tg mice.As a positive control drug,MTX attenuated the pathological changes in joints,but had no beneficial effect on cardiopulmonary inflammation and fibrosis in TNF-Tg mice.Conclusions:DGNTT improved joint lesions and alleviated cardiopulmonary complications in TNF-Tg mice.

Design Optimization of a Novel Axial-radial Flux Permanent Magnet Claw Pole Machine with SMC Cores and Ferrite Magnets

Soft magnetic composite(SMC)material is an ideal soft magnetic material employed for developing 3D magnetic flux electromagnetic equipment,due to its advantages of 3D magnetic isotropy characteristic,low eddy current loss,and simple manufacturing process.The permanent magnet claw pole machine(PMCPM)with SMC cores is a good case that the SMC to be adopted for developing 3D flux electrical machines.In this paper,a novel axial-radial flux permanent magnet claw pole machine(ARPMCPM)with SMC cores and ferrite magnets is proposed.Compared with the traditional PMCPM,the proposed ARPMCPM is designed with only one spoke PM rotor and its whole structure is quite compact.For the performance prediction,the 3D finite element method(FEM)is used.Meanwhile,for the performance evaluation,a previously developed axial flux claw pole permanent magnet machine(AFCPM)is employed as the benchmark machine and all these machines are optimized by using the combined multilevel robust Taguchi method.It can be seen that the proposed ARPMCPM is with higher torque/weight density and operation efficiency.

Ameliorative effects of potassium on drought-induced decreases in fiber length of cotton(Gossypium hirsutum L.) are associated with osmolyte dynamics during fiber development

Fiber length of cotton(Gossypium hirsutum L.)decreases under drought stress,potassium(K)could diminish the decreased caused by drought,but the mechanism associated with this alleviation effect is not clear.We evaluated the effect of K on fiber elongation using two cotton cultivars,Simian 3 and Siza 3,grown in well-watered and drought-stressed conditions.Potassium fertilizer(K2O)was applied 0,150,or 300 kg ha?1 in each growing condition.Drought stress reduced the final fiber length due to a decline in the maximum rate of rapid elongation(Vmax,mmday?1).The application of K alleviated the droughtinduced fiber length reduction by increasing Vmax.At 10 and 15 days post-anthesis(DPA),drought significantly reduced osmotic potential(OP)and increased K+and malate contents at all K rates,relative to well-watered conditions,which was associated with increased activities of phosphoenolpyruvate carboxylase(PEPC),V-ATPase,PPase,and PM H+-ATPase in cotton fiber.However,the relative contribution of K+and malate to OP declined under drought in comparison with well-watered condition.Compared with control without K,K application decreased OP and increased the accumulation of osmolytes(K+,malate and soluble sugar)as well as the activities of related enzymes in fiber irrespective of water treatments.Moreover,K application increased osmotic adjustment during drought,and improved the contribution of K+and malate to OP,especially under drought stress.This study showed that drought decreased fiber length by reducing Vmax,and K application ameliorates the decline in fiber elongation due to drought by enhancing osmolytes accumulation and their contribution to OP in fiber cells.

Torque Ripple Reduction of Synchronous Reluctance Machine by Using Asymmetrical Barriers and Hybrid Magnetic Core

As there is no need of permanent magnet(PM)material and only silicon steel sheet required on the rotor,synchronous reluctance machine(SynRM)can be used for many applications and draws a great research interest.For the SynRM,the torque ripple is a big issue and a great of work could been done on reducing it.In this paper,asymmetrical magnetic flux barriers in the SynRM rotor were studied comprehensively,including angle and width of each layer and each side of the magnetic barrier.The SynRMb with asymmetrical and parallel magnetic flux barrier was found as the best way to design SynRM based on the multi-objective design optimization method.Moreover,each parameter was studied to show the design rule of the asymmetrical magnetic flux barrier.As the average torque will be reduced with the asymmetrical barrier is used,the grain-oriented silicon steel is used on stator teeth of the SynRMb(SynRMbG)was proposed and studied.The analysis results show that the proposed new method can make the SynRM have better performance.

Robust signal recovery algorithm for structured perturbation compressive sensing

It is understood that the sparse signal recovery with a standard compressive sensing（CS） strategy requires the measurement matrix known as a priori. The measurement matrix is, however, often perturbed in a practical application.In order to handle such a case, an optimization problem by exploiting the sparsity characteristics of both the perturbations and signals is formulated. An algorithm named as the sparse perturbation signal recovery algorithm（SPSRA） is then proposed to solve the formulated optimization problem. The analytical results show that our SPSRA can simultaneously recover the signal and perturbation vectors by an alternative iteration way, while the convergence of the SPSRA is also analytically given and guaranteed. Moreover, the support patterns of the sparse signal and structured perturbation shown are the same and can be exploited to improve the estimation accuracy and reduce the computation complexity of the algorithm. The numerical simulation results verify the effectiveness of analytical ones.

Electromagnetic Performance Analysis of Flux-Switching Permanent Magnet Tubular Machine with Hybrid Cores

The performance of traditional flux switching permanent magnet tubular machine(FSPMTM)are improved by using new material and structure in this paper.The existing silicon steel sheet making for all mover cores or part of stator cores are replaced by soft magnetic composite(SMC)cores,and the lamination direction of the silicon steel sheet in stator cores have be changed.The eddy current loss of the machine with hybrid cores will be reduced greatly as the magnetic flux will not pass through the silicon steel sheet vertically.In order to reduce the influence of end effect,the unequal stator width design method is proposed.With the new design,the symmetry of the permanent magnet flux linkage has been improved greatly and the cogging force caused by the end effect has been reduced.Both 2-D and 3-D finite element methods(FEM)are applied for the quantitative analysis.

Cause Analysis of Crack Formation in HRB400 Screw-Thread Steel

The analysis of the crack on the HRB400 screw-thread steel surface has been carried out by means of metallographic microscope, scanning electron microscope and EDAX. It is shown that the type of inclusions in the crack steel samples is mainly class B oxide, C silicate, and the inclusion size of the majority below 10 μm, and a small number of large inclusions are observed. The content of oxygen in the steel is high, and the carbon segregation is the main reason of the crack formation of HRB400 screw-thread steel. The measures to improve the crack formation of HRB400 screw-thread steel are put forward, which provides a powerful basis for the practical production.

Development of a New Flux Switching Transverse Flux Machine with the Ability of Linear Motion

This paper proposes a new rotary flux switching transverse flux machine with the ability of linear motion(FSTFMaLM),in which both the stator and the rotor cores are made by using soft magnetic composite(SMC)materials.With the special design pattern,for the rotary motion model,the proposed machine can combine both the advantages of the flux switching permanent magnet machine(FSPMM)and the transverse flux machine(TFM).It can output with relatively high torque density,and as there is no windings or the magnets on the rotor cores,the proposed machine can operate in the high speed region to improve the output power.With the adoption of the SMC materials,the manufacturing of this machine can be quite easy.By stacking the rotor core together and prolong it with the determined length in the axial direction,in addition with the special control algorithm,the proposed machine can have the ability of the linear motion.In this paper,the operation principle of this machine has been explained and the design methods are also presented.To seek the better performance,the main dimension of the machine is optimized,and for the performance evaluation,the finite element method(FEM)is adopted.The proposed machine can be used for the electric driving systems,robotic systems or other applications where the linear motion ability is required.

Commercial genetically modified corn and soybean are poised following pilot planting in China

"Who will feed China?"This was a question raised by Lester Brown,the director of the World Watch Institute in the United States,in 1994.He predicted that China's grain production would decrease from 340 million tons in 1990 to 272 million tons by 2030,a 20%decrease,while China's population would reach 1.6 billion(Brown,1995).If the dietary structure was not improved,China would need to import 200-369 million tons of grain,equivalent to the global grain trade at the time.He projected the high possibility of a food crisis in China,which might further trigger a global food crisis.However,with the joint efforts of national agricultural researchers,represented by Yuan Longping,and the Chinese government,China's grain production has achieved 18 consecutive increases from 2004 to 2021.In 2022,grain production in China reached 633 million tons(NBS and Statistics,2022),while the population remained stable at 1.4 billion.As a result,China has achieved complete self-sufficiency in its staple food supply and has demonstrated to the international community through practical actions that the Chinese people can feed themselves.

Red-emissive carbon quantum dots minimize phototoxicity for rapid and long-term lipid droplet monitoring

Long-term fluorescence monitoring of subcellular organelles is crucial for cellular physiology and pathology studies.Lipid droplets(LDs)are increasingly recognized for their involvement in various biological processes,to influence disease development through diverse behaviors However,existing LD probes face challenges in achieving high targeting and long-term monitoring due to poor photostability and long-term phototoxicity.Carbon quantum dots(CQDs)have gained prominence due to their exceptional fluorescence properties,but their prevalent blue excitation wavelength presents difficulties for long-term imaging.Herein,we synthesized red-emissive carbon quantum dot(R-CQDs)with superior photobleaching resistance and red-emission,thus enabling harmlessly fluorescence monitoring of cells longer than3 h.In addition,R-CQD exhibits suitable amphiphilicity and remarkable solvatochromic effect,allowing rapid targeting to LDs for immediate imaging without cumbersome washing steps.Hence,R-CQD shows high performance for extended observation of dynamic LD behavior in various biological processes,which is confirmed by documenting the course of LDs during starvation as well as lipotoxicity.Compared to commercial probes,R-CQD extends live cell imaging time by at least 9-fold,facilitating the study of LD behavioral characteristics under diverse physiological or pathological conditions.This work provides a reliable fluorescence tool for tracking intercellular microenvironment dynamically thus to understand the divers biological or disease mechanism.

电视短剧《逃出大英博物馆》的文化诉求探析

《逃出大英博物馆》电视短剧以创意叙事,深刻触及文化身份与文物归还的敏感议题。该剧虚构了一场文物“逃亡”,不仅是对历史伤痕的艺术再现,更是对文化归属权的深情呼唤。它不仅激发了公众对文化遗产保护的热情,也促进了全球范围内对文化尊重与交流的深刻反思。其文化诉求在于唤醒国人对传统文化的珍视与传承意识,同时促进国际间关于文物归属问题的理性对话,展现了文化自觉与民族自豪感的时代风貌。

Identification and validation of cardiac nonconserved human-specific enhancers

Congenital heart disease(CHD)is one of the most common causes of neonatal mortality.The worldwide morbidity of CHD is 9.410%o,while the proportion of CHD patients who are reported to carry mutations in coding regions is<50%.Enhancers play an important role in the spatio-temporal expression of target genes,and a lot of related variations are associated with CHD.There are conserved and nonconserved enhancers.

Trends in the global commercialization of genetically modified crops in 2023

The commercialization of genetically modified(GM)crops has increased food production,improved crop quality,reduced pesticide use,promoted changes in agricultural production methods,and become an important new production strategy for dealing with insect pests and weeds while reducing the cultivated land area.This article provides a comprehensive examination of the global distribution of GM crops in 2023.It discusses the internal factors that are driving their adoption,such as the increasing number of GM crops and the growing variety of commodities.This article also provides information support and application guidance for the new developments in global agricultural science and technology.

Low-cost,μm-thick,tape-free electronic tattoo sensors with minimized motion and sweat artifacts

Electronic tattoos(e-tattoos),also known as epidermal electronics,are ultra-thin and ultra-soft noninvasive but skin-conformable devices with capabilities including physiological sensing and transdermal stimulation and therapeutics.The fabrication of e-tattoos out of conventional inorganic electronic materials used to be tedious and expensive.Recently developed cut-and-paste method has significantly simplified the process and lowered the cost.However,existing cut-and-paste method entails a medical tape on which the electronic tattoo sensors should be pasted,which increases tattoo thickness and degrades its breathability.To address this problem,here we report a slightly modified cut-and-paste method to fabricate low-cost,open-mesh e-tattoos with a total thickness of just 1.5μm.E-tattoos of such thinness can be directly pasted on human skin and conforms to natural skin texture.We demonstrate that this ultra-thin,tape-free e-tattoo can confidently measure electrocardiogram(ECG),skin temperature,and skin hydration.Heart rate and even respiratory rate can be extracted from the ECG signals.A special advantage of such ultra-thin e-tattoo is that it is capable of high-fidelity sensing with minimized motion artifacts under various body movements.Effects of perspiration are found to be insignificant due to the breathability of such e-tattoos.

All-weather,natural silent speech recognition via machine-learning-assisted tattoo-like electronics

The internal availability of silent speech serves as a translator for people with aphasia and keeps human–machine/human interactions working under various disturbances.This paper develops a silent speech strategy to achieve all-weather,natural interactions.The strategy requires few usage specialized skills like sign language but accurately transfers high-capacity information in complicated and changeable daily environments.In the strategy,the tattoo-like electronics imperceptibly attached on facial skin record high-quality bio-data of various silent speech,and the machine-learning algorithm deployed on the cloud recognizes accurately the silent speech and reduces the weight of the wireless acquisition module.A series of experiments show that the silent speech recognition system(SSRS)can enduringly comply with large deformation(~45%)of faces by virtue of the electricitypreferred tattoo-like electrodes and recognize up to 110 words covering daily vocabularies with a high average accuracy of 92.64%simply by use of small-sample machine learning.We successfully apply the SSRS to 1-day routine life,including daily greeting,running,dining,manipulating industrial robots in deafening noise,and expressing in darkness,which shows great promotion in real-world applications.

Highly Robust and Wearable Facial Expression Recognition via Deep-Learning-Assisted,Soft Epidermal Electronics

The facial expressions are a mirror of the elusive emotion hidden in the mind,and thus,capturing expressions is a crucial way of merging the inward world and virtual world.However,typical facial expression recognition(FER)systems are restricted by environments where faces must be clearly seen for computer vision,or rigid devices that are not suitable for the time-dynamic,curvilinear faces.Here,we present a robust,highly wearable FER system that is based on deep-learning-assisted,soft epidermal electronics.The epidermal electronics that can fully conform on faces enable high-fidelity biosignal acquisition without hindering spontaneous facial expressions,releasing the constraint of movement,space,and light.The deep learning method can significantly enhance the recognition accuracy of facial expression types and intensities based on a small sample.The proposed wearable FER system is superior for wide applicability and high accuracy.The FER system is suitable for the individual and shows essential robustness to different light,occlusion,and various face poses.It is totally different from but complementary to the computer vision technology that is merely suitable for simultaneous FER of multiple individuals in a specific place.This wearable FER system is successfully applied to human-avatar emotion interaction and verbal communication disambiguation in a real-life environment,enabling promising human-computer interaction applications.

Chest-scale self-compensated epidermal electronics for standard 6-precordial-lead ECG

Six chest leads are the standardized clinical devices of diagnosing cardiac diseases.Emerging epidermal electronics technology shift the dangling wires and bulky devices to imperceptible wearing,achieving both comfortable experience and high-fidelity measuring.Extending small areas of current epidermal electronics to the chest scale requires eliminating interference from long epidermal interconnects and rendering the data acquisition(DAQ)portable.Herein,we developed a chest-scale epidermal electronic system(EES)for standard precordial-lead ECG and hydration monitoring,including the onlyμm-thick substrate-free epidermal sensing module and the soft wireless DAQ module.An electrical compensation strategy using double channels within the DAQ module and epidermal compensated branches(ECB)is proposed to eliminate unwanted signals from the long epidermal interconnects and to achieve the desired ECG.In this way,the EES works stably and precisely under different levels of exercise.Patients with sinus arrhythmias have been tested,demonstrating the prospect of EES in cardiac diseases.

Highly Robust and Wearable Facial Expression Recognition via Deep-Learning-Assisted, Soft Epidermal Electronics

The facial expressions are a mirror of the elusive emotion hidden in the mind,and thus,capturing expressions is a crucial way of merging the inward world and virtual world.However,typical facial expression recognition(FER)systems are restricted by environments where faces must be clearly seen for computer vision,or rigid devices that are not suitable for the time-dynamic,curvilinear faces.Here,we present a robust,highly wearable FER system that is based on deep-learning-assisted,soft epidermal electronics.The epidermal electronics that can fully conform on faces enable high-fidelity biosignal acquisition without hindering spontaneous facial expressions,releasing the constraint of movement,space,and light.The deep learning method can significantly enhance the recognition accuracy of facial expression types and intensities based on a small sample.The proposed wearable FER system is superior for wide applicability and high accuracy.The FER system is suitable for the individual and shows essential robustness to different light,occlusion,and various face poses.It is totally different from but complementary to the computer vision technology that is merely suitable for simultaneous FER of multiple individuals in a specific place.This wearable FER system is successfully applied to human-avatar emotion interaction and verbal communication disambiguation in a real-life environment,enabling promising human-computer interaction applications.

基于膜解剖的开放前入路腹膜前腹股沟疝修补术

目的通过对腹股沟区膜解剖的了解,辨认开放腹膜前入路手术的正确层面,减少术后复发率和并发症。方法对2006年1月至2018年3月东莞茶山医院450例原发性腹股沟疝患者进行术中观察、组织学分析和术后长期随访。结果腹股沟管有两个内环(中间环和内环)。进入Bogros间隙的"门户"是腹膜和腹膜前筋膜深层之间,而进入Retzius间隙的层面则是腹横筋膜和腹膜前筋膜浅层之间,这两个不连续的膜层面通过切开腹壁下血管处间隙韧带而贯通为一体的腹膜前间隙。术后随访平均53个月,慢性疼痛发生率和复发率均低于1%。结论熟悉腹股沟区膜结构的解剖有助于提高开放腹膜前疝修补术的安全性和可靠性,减少手术并发症和复发率。