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Abstract High torque density and high reliability motors have a wide application prospect in aerospace field, so a hybrid rotor and dual stator motor is studied in this paper. Firstly, to address the problem that the difference in power density between the inner and outer unit motor is so large that it is not suitable for electromagnetic design using the power splitting method, a main dimensioning calculation method based on the equal‐power volume transformation is proposed. The influence of thermal load on the output performance of the inner and outer unit motors is taken into account comprehensively. The main dimensioning expressions for such motors are derived. Secondly, the output performance consistency between the inner and outer unit motors is theoretically analysed, and the optimal angle between the d‐axis of the permanent magnet rotor and the d‐axis of the reluctance rotor is obtained when the motor is operated in the maximum torque per ampere control mode. Finally, a prototype with a rated power of 46.7 kW was developed and load experiments were conducted on it, and the experimental results verified the correctness and feasibility of the theoretical analysis method.

Coal mine conveyor belt and other low-speed large torque system, the torque density and torque stability of the motor requirements are higher, permanent magnet / magnet reluctance hybrid rotor double stator synchronous motor (PM/MRHRDSSM) is just adapted to this requirement, however, the traditional close winding single inverter vector control system control PM/MRHRDSSM provides large torque ripple, high speed fluctuation and large total harmonic distortion (THD) of the current, difficult to be used in actual production and life, this paper proposes a large torque open winding-permanent magnet / magnet reluctance hybrid rotor double stator synchronous motor(OW-PM/MRHRDSSM) based on SVPWM dual inverter control strategy, and analysis of open winding double inverter structure, and its voltage vector mathematical model, using the existing two-level inverter as a basis, the bilateral inverter separately discussed its role and control method, as well as the decomposition method of synthetic voltage vector and the inverter device in the small sector on-time, the end of this paper through simulation to compare the traditional close winding single inverter vector control system control PM/MRHRDSSM and the large torque OW-PM/MRHRDSSM based on SVPWM dual inverter control strategy to prove the effectiveness of the proposed method in reducing torque ripple, speed fluctuation and THD of current during motor operation.

Abstract This paper proposes a maximum torque per ampere (MTPA) control method for a permanent magnet reluctance hybrid rotor dual stator synchronous motor (PMRHRDSSM) based on a sliding mode speed controller, in response to the complex and special electromagnetic relationship of the motor. The paper focuses on the special electromagnetic relationship of PMRHRDSSM with stator winding series structure. Firstly, the trajectory equation of PMRHRDSSM MTPA stator current vector is derived, and based on the relationship between PMRHRDSSM torque and reluctance dq‐axis current, a PMRHRDSSM current controller that meets MTPA constraints is designed. Afterwards, a PMRHRDSSM sliding mode speed controller was designed with input speed error and output reference torque. Finally, an experimental platform for the proposed control method was established, and the control method was experimentally validated.

Abstract Compared with a traditional low‐speed high‐torque permanent magnet synchronous motor (PMSM), a permanent magnet (PM)/reluctance hybrid rotor dual‐stator synchronous motor (PM/RHRDSSM) has the advantages of high torque density and high space utilization. This type of motor is composed of a "back‐to‐back" PM + reluctance hybrid rotor and an inner and outer double stator. The number of poles of the inner and outer unit motors is the same, and the inner and outer stator windings are connected in series, driven by a single inverter. Due to the special mechanical structure and electromagnetic relationship of PM/RHRDSSM, traditional PMSM and synchronous reluctance motor maximum torque per ampere (MTPA) control strategies are no longer applicable. In response to this issue, the authors establishe a PM/RHRDSSM mathematical model of stator winding series structure and propose a MTPA control strategy suitable for this new type of motor. This strategy is aimed at the special mathematical model of PM/RHRDSSM and derives the analytical expression of MTPA trajectory, which minimises the required stator current amplitude of PM/RHRDSSM at various load torques, thereby minimising the motor copper loss. Finally, the effectiveness and practicality of the proposed control strategy were verified through simulation and experiments.

The objective of this study was to investigate the potential of Lacticaseibacillus rhamnosus L08 (L. rhamnosus L08) to enhance the functionality, improve the taste, and explore efficient storage methods of blue honeysuckle juice (BHJ). The fermentation process resulted in an increase in the levels of polyphenols, flavonoids, and anthocyanins in blue honeysuckle juice, which was attributed to the action of β-glucosidase on specific phenolic compounds, namely Cyanidin-3-Glucoside and Quinic acid. The increase in phenolic content resulted in an enhancement of the antioxidant capacity of BHJ. The fermentation processed, utilizing L. rhamnosus L08, not only enhanced the flavor and taste of BHJ, but also mitigated its bitter aftertaste while minimizing the loss of bioactive components during storage. In conclusion, this study demonstrated a potential avenue for enhancing the commercial value and dietary significance of this lesser-known superfruit, with fermented BHJ emerging as a promising innovation in the field of functional foods.

Abstract Worldwide, myocardial infarction (MI) is the leading cause of death and disability-adjusted life years lost. Recent researches explored new methods of detecting biomarkers that can predict the risk of developing myocardial infarction, which includes identifying genetic markers associated with increased risk. We induced myocardial infarction in mice by occluding the left anterior descending coronary artery and performed TTC staining to assess cell death. Next, we performed ChIP assays to measure the enrichment of histone modifications at the promoter regions of key genes involved in mitochondrial fission. We used qPCR and western blot to measure expression levels of relative apoptotic indicators. We report that miR-181a inhibits myocardial ischemia-induced apoptosis and preserves left ventricular function after MI. We show that programmed cell death protein 4 (PDCD4) is the target gene involved in miR-181a-mediated anti-ischemic injury, which enhanced BID recruitment to the mitochondria. In addition, we discovered that p53 inhibits the expression of miR-181a via transcriptional regulation. Here, we discovered for the first time a mitochondrial fission and apoptosis pathway which is controlled by miR-181a and involves PDCD4 and BID. This pathway may be controlled by p53 transcriptionally, and we presume that miR-181a may lead to the discovery of new therapeutic and preventive targets for ischemic heart diseases.

As information technology continues to evolve, cloud data centres have become increasingly prominent as the preferred infrastructure for data storage and processing. However, this shift has introduced a new array of security challenges, necessitating innovative approaches distinct from traditional network security architectures. In response, the Zero Trust Architecture (ZTA) has emerged as a promising solution, with micro-segmentation identified as a crucial component for enabling continuous auditing and stringent security controls. VxLAN technology is widely utilized in data centres for tenant isolation and virtual machine interconnection within tenant environments. Despite its prevalent use, limited research has focused on its application in micro-segmentation scenarios. To address this gap, we propose a method that leverages VLAN and VxLAN many-to-one mapping, requiring that all internal data centre traffic routes through the VxLAN gateway. This method can be implemented cost-effectively, without necessitating business modifications or causing service disruptions, thereby overcoming the challenges associated with micro-segmentation deployment. Importantly, this approach is based on standard public protocols, making it independent of specific product brands and enabling a network-centric framework that avoids software compatibility issues. To assess the effectiveness of our micro-segmentation approach, we provide a comprehensive evaluation that includes network aggregation and traffic visualization. Building on the implementation of micro-segmentation, we also introduce an enhanced asset behaviour algorithm. This algorithm constructs behavioural profiles based on the historical traffic of internal network assets, enabling the rapid identification of abnormal behaviours and facilitating timely defensive actions. Empirical results demonstrate that our algorithm is highly effective in detecting anomalous behaviour in intranet assets, making it a powerful tool for enhancing security in cloud data centres. In summary, the proposed approach offers a robust and efficient solution to the challenges of micro-segmentation in cloud data centres, contributing to the advancement of secure and reliable cloud infrastructure.

Aiming at the shortcomings of complex mechanical transmission structure and low efficiency of the existing belt conveyor driven by asynchronous motor, this paper focuses on the investigation of a new type of low-speed high-torque-density direct-drive permanent magnet synchronous motor (LHDPMSM) for driving the belt conveyor. The proposed LHDPMSM utilizes external rotor structure to achieve the goal of fully direct drive of the belt conveyor. First, the topology and advantages of the straight-shape external-rotor LHDPMSM is introduced. Then the selection rules of the pole-slot combination are studied. Furthermore, an improved subdomain model is established based on the idea of segmentation for fast calculation of the no-load magnetic field of the proposed straight-shape external-rotor LHDPMSM. Moreover, the operating performance of the proposed LHDPMSM with load fluctuations was verified by FEA. In addition, an efficient cooling system based on $Z$ -shape water channels and hollow shaft was designed, and a LPTN model was established for temperature fast calculation. Since the cooling system has a negative impact on the shaft mechanical strength, the mechanical strength of the shaft and other fragile components of the LHDPMSM was analyzed to ensure the safe operation of the motor. Finally, a prototype is manufactured and tested to validate the design concept introduced in this paper.

In actual production, errors in manufacturing and assembly may lead to misalignment of the stator and rotor and uneven air gap magnetic density, which affects the running performance of the motor. The influence of rotor dynamic eccentricity on air-gap flux density, cogging torque and loss is studied by combining analytical method and finite element analysis. The eccentric rotor model of low-speed high-torque permanent magnet synchronous motor (LHPMSM) is established on Maxwell 2D. The results show that with the increase of the rotor eccentricities, the back EMF and stator iron loss changeless, the cogging torque decreases slightly. The output torque increases slightly, but the harmonic distortion rate of air gap magnetic density and stator copper loss increase significantly.

Abstract Permanent magnet synchronous motor (PMSM) shows the great potential for use in direct drive system because of its excellent low‐speed direct‐drive capability. However, it suffers from the adverse effect of the cogging torque in comparison with the asynchronous motor. Therefore, reducing the cogging torque, especially the external‐rotor PMSM (ERPMSM) for belt conveyor application, is necessary for enhancing the stable operation and precise positioning performances of the belt conveyor.Herein, a novel tangential magnetization low‐speed high‐torque ERPMSM is proposed and analysed. Furthermore, the expression of the cogging torque of the proposed ERPMSM is derived by energy method. Based on the special structure of the ERPMSM, a new method for cogging torque reduction is introduced. The comparative FEA results for four ERPMSM models are presented to verify the accuracy and effectiveness of this method. The accuracy of the cogging torque FEA results is confirmed by a prototype. Finally, the influence of this method on ERPMSM performance is also analysed carefully in this paper.

Molecular assays on nasopharyngeal swabs act as a confirmatory test in coronavirus disease (COVID-19) diagnosis. However, the technical requirements of nasopharyngeal sampling and molecular assays limit the testing capabilities. Recent studies suggest the use of saliva for the COVID-19 diagnostic test. In this study, 44 patients diagnosed with COVID-19 in The Third People’s Hospital of Shenzhen were enrolled. Saliva and serum specimens were obtained at different time points and the immunoglobulins against SARS-CoV-2 were measured. The results showed that saliva IgA presented a higher COI value than IgG and IgM. In matched saliva and serum samples, all saliva samples presented lower IgG levels than serum samples, and only one saliva sample presented a higher IgM level. The conversion rates of saliva IgA and the detection of viral nucleic acids were analyzed in the first and second weeks after hospitalization. The positive rates increased when combining saliva IgA and viral nucleic acid detection. In conclusion, our results provide evidence that saliva IgA could serve as a useful index for the early diagnosis of COVID-19.

Abstract In order to meet the higher requirements (i.e. large scale, high reliability and direct drive) of generators used for offshore wind turbine, a novel direct drive module dual stator brushless doubly‐fed generator (DSBDFG) with cage‐barrier rotor having many outstanding merits is proposed in this paper. The fundamental structure, operation principle and power flow are presented. The electromagnetic design methods of the proposed generator including power distribution of inner and outer machines, the relationship of pole number, slot number and module number, and winding design are thoroughly investigated. In order to solve the problems in structure brought by module design and reduce the weight as much as possible, a mechanical construction applied for module DSBDFG is proposed. Finally, the correctness of the proposed electromagnetic design method and the stability of the proposed mechanical construction are verified based on finite element analysis respectively.

Building the security mechanism for Controller Area Network (CAN) to defend against attack has drawn substantial attention recently. Fingerprinting ECUs to provide the ability of authentication based on the physical characteristics can protect the CAN network effectively. The clock skew which is unique and stable can be exploited to pinpoint the attacker and detect intrusion. However, a common downside of existing clock-skew-based approaches is that the estimation process can be affected by the message scheduling or arbitration. In our work, a novel intrusion detection system (IDS) that exploits the inherent difference in the clock of devices for automotive CAN network is designed. The estimation process of clock skew in our approach relies only on the time measurement of a single CAN frame. Thus, the disturbance from the data-link layer can be avoided. Since the performance of our IDS depends heavily on the accuracy of estimated clock skew, our approach is evaluated on CAN networks with different settings to simulate cases in which the sampling rate is sufficient or not. The feasibility as well as the limitation of our approach are presented in our work. The evaluation shows that our IDS can identify the sender and detect attacks with an average identification rate of more than 99.7% when the sampling rate is sufficient. Besides, the performance degradation as low sampling accuracy is shown and feasible measures for improvement are also discussed.

In this manuscript, a method of generating an ultra-long optical needle (depth-to-width ratio 37.5:1) is proposed and demonstrated by focusing an azimuthally polarized beam. In theory, the action mechanism between the incident beam and the amplitude modulation element, the spiral phase modulation element, the focusing lens were studied based on the Richards and Wolf's theory. The relationship between the intensity distribution of the optical needle and the structure parameter of the element were obtained, thus leading to the complete design model and design standard. In experiment, the annular amplitude modulation element and spiral phase modulation element were fabricated by lithography. The optical needle was obtained based on a custom-designed optical setup in our laboratory. The optical system consists of an annular aperture (3.9-mm inner diameter, 80-μm annular width), a spiral phase plate (topological charge of 1), and an objective lens with numerical aperture of 0.95. Finally, an optical needle with a subwavelength size (0.416λ) and an ultra-long depth of focus (15.6λ) was obtained, showing an excellent agreement with our theoretical model.

The brushless doubly fed generator (BDFG) has been a research focus of wind power generation due to its inherent promising features. Although it is important to consider the effect of losses on the design and analysis of the BDFG, there are a few related comprehensive studies. Moreover, a hybrid rotor is studied to improve the performance of BDFG, which brings greater challenges to the loss calculation. The aim of this paper is to propose the accuracy calculation methods of core loss and copper loss for the studied BDFG with hybrid rotor. The core loss calculation model which taken the influence of harmonics, alternating magnetization, rotating magnetization and two-dimensional magnetic property of material into account is proposed based on the analysis of the magnetic field characteristics. In order to calculate the copper loss considering the skin effect, the inductive current of the assisted cage bars which is difficult to obtain directly is calculated. The accuracy and correctness of the proposed approaches and models are validated by experimental results from a 25kW prototype BDFG with hybrid rotor. In addition, the proposed loss calculation method, especially the core loss calculation model, is also applicable to BDFG with other rotor structure which is operated by the magnetic field modulation mechanism.

Abstract Background The increasing availability of high-throughput sequencing data provides researchers with unprecedented opportunities to investigate viral genetic elements in host genomes that contribute to virus-linked cancers. Almost all of the available computational tools for secondary analysis of sequencing data detect viral infection or genome integration events. However, viral oncogenes expression is likely of importance in carcinoma. We therefore developed a new software, DisV-HPV16, for the evaluation of HPV16 oncogenes expression. Results HPV16 virus and viral oncogenes expression was detected more rapidly using DisV-HPV16 compared to other software. DisV-HPV16 was proved highly convenient for detecting candidate virus after modification of the reference file. The accuracy of DisV-HPV16 was empirically confirmed in laboratory experiments. DisV-HPV16 exhibited greater reliability than other software. Conclusions DisV-HPV16 is a new, dependable software to detect virus and viral oncogenes expression through analysis of RNA sequencing data. Use of DisV-HPV16 can yield deeper, more comprehensive insights into virus infection status and viral and host cell gene expression.

Bacterial blight, which is one of the most common soybean diseases, is responsible for considerable yield losses. In this study, a novel Xanthomonas vasicola strain was isolated from the leaves of soybean plants infected with bacterial blight under field conditions. Sequencing the X. vasicola genome revealed type-III effector-coding genes. Moreover, the hrpG deletion mutant was constructed. To identify the soybean genes responsive to HrpG, two chromosome segment substitution lines (CSSLs) carrying the wild soybean genome, but with opposite phenotypes following Xanthomonas inoculations, were used to analyze gene expression networks based on RNA sequencing at three time points after inoculations with wild-type Xanthomonas or the hrpG deletion mutant. To further identify the hub genes underlying soybean responses to HrpG, the genes located on the substituted chromosome segments were examined. Finally, a combined analysis with the QTLs for resistance to Xanthomonas identified 35 hub genes in the substituted chromosomal segments that may help regulate soybean responses to Xanthomonas and HrpG. Furthermore, two candidate genes in the CSSLs might play pivotal roles in response to Xanthomonas.

In this paper, the design and analysis of a 30 kW, 30,000 r/min high-speed permanent magnet motor (HSPMM) for compressor application are provided. In order to provide a reasonable electromagnetic design scheme, the electromagnetic performances of the HSPMM under different structures are analyzed and compared by the finite element method (FEM). The thermal performances and cooling system of the HSPMM are, respectively, analyzed and designed by computational fluid dynamics (CFD). Finally, the HSPMM’s rotor strength is studied by both FEM and analytical methods, and the influencing factors of which are also researched in this paper.

As a kind of information-intensive 3D representation, point cloud rapidly develops in immersive applications, which has also sparked new attention in point cloud compression. The most popular dynamic methods ignore the characteristics of point clouds and use an exhaustive neighborhood search, which seriously impacts the encoder’s runtime. Therefore, we propose an improved compression means for dynamic point cloud based on curvature estimation and hierarchical strategy to meet the demands in real-world scenarios. This method includes initial segmentation derived from the similarity between normals, curvature-based hierarchical refining process for iterating, and image generation and video compression technology based on de-redundancy without performance loss. The curvature-based hierarchical refining module divides the voxel point cloud into high-curvature points and low-curvature points and optimizes the initial clusters hierarchically. The experimental results show that our method achieved improved compression performance and faster runtime than traditional video-based dynamic point cloud compression.

With the fast development of social networks, more and more data has been generated. Finding useful information among these data is important. Subgraph matching is the method that can be used in social networks for social search, recommender systems, and so on. In this paper, we choose five typical graph matching methods which are VF2, SPath, TurboISO, BoostIso, and RI to value their performance and scalability in social networks. These methods are verified by three social network data sets whose node’s number vary from thousands to millions. According to the experiments, we can find that VF2 and RI is applicable for rather small graphs while SPath performs better in large graph when average degree of graph is small. When graph with high average degree, TurboISO and BoostIso performs better. What is more, we also compare the efficiency of different matching order when searching. The order choosing strategy proposed by RI is better.

The movable super-diffraction optical needle (MSON) is a tightly focused beam like a “needle”, which can realize vector scanning on the focusing plane. Not only does it have a long focal depth, but its resolution also exceeds the diffraction limit. The modulation and control technology required for generating MSON by oblique incidence is explored in this manuscript for the purpose of processing high-aspect-ratio, sub-wavelength structures. As the optical needle generated by traditional methods is static and sensitive to variation of the angle information of the incident beam, here we introduce a confocal scanning system by using a two-dimensional galvanometer system, a scan lens, and a tube lens to control the oblique incidence angle. The effects of the oblique incidence angle on the resolution, depth of focus, uniformity, and side lobes of the MSON were analyzed. Further, the voltage-controlled liquid crystal located between the scan lens and the 2D galvanometer system can be used to compensate for the additional phase difference caused by oblique incidence. The aspect ratio is defined as the ratio of depth of focus to resolution. By modulating and controlling the light field, the MSON with high aspect ratio (7.36), sub-diffractive beam size (0.42λ), and long depth of focus (3.09λ) has been obtained with homogeneous intensity, and suppressed side lobes. High speed, high axial positioning tolerance, and high-resolution laser processing can also be achieved, which removes the restrictions presented by traditional laser processing technology, for which high resolution and long depth of focus cannot be achieved simultaneously.

Breastfeeding has a wide range of benefits for both infants and mothers. The identification of factors associated with exclusive breastfeeding (EBF) are important to increase the prevalence of EBF. The study aimed to determine the prevalence of EBF within the first six months and its associated factors in Kaiyuan, Yunnan Province, Southwest China. This cross-sectional study was conducted in Kaiyuan, a middle-sized city of Yunnan Province, Southwest China. Mothers of infants under twelve months were randomly selected for a face to face interview in four towns (two in urban areas and two in rural areas) in Kaiyuan. A structured questionnaire was applied for collection of sociodemographic information, mothers' and infants' health, and breastfeeding information. A 24-hour food recall survey was used to collect infant feeding information. A logistic regression analysis was performed to identify the factors independently associated with exclusive breastfeeding for infants up to six months of age. The number of 417 mothers with infants under six months was interviewed. The prevalence of EBF at six months was 27.34%. Logistic regression indicated that EBF within six months was more likely to be practiced by mothers who had higher average household income per year (OR = 2.09, 95% CI: 1.05-4.17 p = 0.037; OR = 1.85, 95% CI: 1.04-3.28 p = 0.037), and mothers who received breastfeeding information (OR = 2.46, (95%CI: 1.45-4.18, p = 0.0009). The prevalence of EBF in Kaiyuan, Southwest China is considerably lower than national and international recommendations. Yearly household income, and mothers who received breastfeeding information are associated with higher EBF prevalence. Breastfeeding information should be given to mothers in order to increase the prevalence of EBF.