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Abstract Observational data suggest a link between gut microbiota and immune-related vasculitis, but causality remains unclear. A bidirectional mendelian randomization study was conducted using public genome-wide data. The inverse-variance-weighted (IVW) method identified associations and addressed heterogeneity.Families Clostridiaceae 1 and Actinomycetaceae correlated positively with granulomatosis with polyangiitis risk, while classes Lentisphaeria and Melainabacteria, and families Lachnospiraceae and Streptococcaceae showed negative associations. Behçet's disease was positively associated with the risk of family Streptococcaceae abundance. And other several gut microbiota constituents were identified as potential risk factors for immune-related vasculitis. Furthermore, combining positive association results from the IVW analysis revealed numerous shared gut microbiota constituents associated with immune-related vasculitis. MR analysis demonstrated a causal association between the gut microbiota and immune-related vasculitis, offering valuable insights for subsequent mechanistic and clinical investigations into microbiota-mediated immune-related vasculitis.

Abstract Objective Recent studies have indicated a potential association between giant cell arteritis (GCA) and diabetes mellitus, encompassing both type 1 diabetes (T1D) and type 2 diabetes (T2D). However, the exact nature of this relationship requires further investigation to be fully elucidated. Methods Genetic links between T1D/T2D and GCA were explored using data from genome-wide association studies available to the public, focusing on populations of European ancestry. We applied a bidirectional mendelian randomization (MR) approach to assess the potential association between these diseases. Confirmatory analyses, including additional datasets and a comprehensive meta-analysis, were utilized. The inverse-variance-weighted (IVW) method was applied to pinpoint heterogeneity and pleiotropy, while subsequent sensitivity analyses aimed to trace the origins of any heterogeneity. Results Initial analysis demonstrated a correlation between T1D and an elevated likelihood of developing GCA (IVW odds ratio = 1.33, with a 95% confidence interval of 1.22–1.46, and a P-value of 9.42E−10). The causal association was verified through four validation datasets and meta-analysis (all P-value

Abstract Mesh reflector antennas are widely used in space tasks owing to their light weight, high surface accuracy, and large folding ratio. They are stowed during launch and then fully deployed in orbit to form a mesh reflector that transmits signals. Smooth deployment is essential for duty services; therefore, accurate and efficient dynamic modeling and analysis of the deployment process are essential. One major challenge is depicting time-varying resistance of the cable network and capturing the cable-truss coupling behavior during the deployment process. This paper proposes a general dynamic analysis methodology for cable-truss coupling. Considering the topological diversity and geometric nonlinearity, the cable network’s equilibrium equation is derived, and an explicit expression of the time-varying tension of the boundary cables, which provides the main resistance in truss deployment, is obtained. The deployment dynamic model is established, which considers the coupling effect between the soft cables and deployable truss. The effects of the antenna’s driving modes and parameters on the dynamic deployment performance were investigated. A scaled prototype was manufactured, and the deployment experiment was conducted to verify the accuracy of the proposed modeling method. The proposed methodology is suitable for general cable antennas with arbitrary topologies and parameters, providing theoretical guidance for the dynamic performance evaluation of antenna driving schemes.

A comprehensive and comparative study of the thermal-oxygen aging and tribological properties of antioxidant 6PPD synergized with carbon nanotubes (CNTs) and graphene (GE)-reinforced hydrogenated nitrile rubber (HNBR) composites was performed using molecular simulations and experiments. The results indicated that GE exhibits superior capabilities in inhibiting the volatilization and migration of the antioxidant 6PPD compared to CNTs and enhancing the thermal and oxygen aging resistance of HNBR. The surface morphology of the HNBR composites was characterized using scanning electron microscopy (SEM) and X-ray spectroscopy (XPS), which revealed the different enhancement mechanisms of CNTs and GE. The mechanical and tribological properties of the HNBR composites were experimentally investigated before and after the thermal-oxygen aging. The results revealed that the tensile and tear strengths of the 6PPD/HNBR composites with added GE increased by approximately 4% compared to those of the 6PPD/HNBR composites with added CNTs. The coefficient of friction decreased by approximately 7%. Finally, the wear surface morphologies of the HNBR composites were characterized using SEM and energy dispersive spectrometer (EDS). These results further indicate that the larger specific surface area of GE can be better combined with HNBR, improving its overall thermal-oxygen aging and tribological properties.

Abstract Background With the development of single-cell technology, many cell traits can be measured. Furthermore, the multi-omics profiling technology could jointly measure two or more traits in a single cell simultaneously. In order to process the various data accumulated rapidly, computational methods for multimodal data integration are needed. Results Here, we present inClust+, a deep generative framework for the multi-omics. It’s built on previous inClust that is specific for transcriptome data, and augmented with two mask modules designed for multimodal data processing: an input-mask module in front of the encoder and an output-mask module behind the decoder. InClust+ was first used to integrate scRNA-seq and MERFISH data from similar cell populations, and to impute MERFISH data based on scRNA-seq data. Then, inClust+ was shown to have the capability to integrate the multimodal data (e.g. tri-modal data with gene expression, chromatin accessibility and protein abundance) with batch effect. Finally, inClust+ was used to integrate an unlabeled monomodal scRNA-seq dataset and two labeled multimodal CITE-seq datasets, transfer labels from CITE-seq datasets to scRNA-seq dataset, and generate the missing modality of protein abundance in monomodal scRNA-seq data. In the above examples, the performance of inClust+ is better than or comparable to the most recent tools in the corresponding task. Conclusions The inClust+ is a suitable framework for handling multimodal data. Meanwhile, the successful implementation of mask in inClust+ means that it can be applied to other deep learning methods with similar encoder-decoder architecture to broaden the application scope of these models.

Laser powder bed fusion (L-PBF) technology offers significant advantages, such as lightweight and miniaturized product fabrication and short manufacturing cycles. Circular channels are widely utilized in hydraulic manifold blocks due to their favorable hydrodynamic properties. However, when manufactured using L-PBF, circular channels often exhibit shape deviations caused by residual stresses. In this study, Ti6Al4V (TC4) circular channels with various processing parameters were produced through L-PBF. The influence of scanning speed and laser power on the actual channel profile was investigated. A novel deformation prediction model for circular channels was established based on the Euler–Bernoulli theory. This model accurately predicts deformations resulting from residual stresses during horizontal manufacturing of circular channels using L-PBF, considering the interaction between forces and deformations across different manufactured layers. Furthermore, the model can be employed for channel shape compensation design. The results indicated excellent agreement between the proposed deformation prediction model and the profile of the experimentally manufactured samples. Using the channel shape compensation model for circular channels substantially can reduce the root mean square (RMS) deviation, thereby improving dimensional accuracy.

Contact with nature is believed to enhance mental health through the process of human psychological restoration. However, prolonged indoor living limits individuals’ exposure to nature, potentially hindering the timely alleviation of stress and fatigue induced by work. While biophilic design is recognized as a potential solution, its impact on the restoration process has not been extensively studied, particularly in relation to its various design patterns. Therefore, it is important to determine the restorative effects of different patterns of biophilic design and their combination in order to guide the practical application of biophilic design. In this study, the effects of two typical biophilic design patterns and their combination on attention restoration were measured using subjective scales, cognitive tasks, and functional near-infrared spectroscopy (fNIRS) in a simulated real workspace. The results suggest a significant enhancement in the restorative impact on cognitive performance and physiological benefits when combining two biophilic design patterns, while a single design pattern does not yield the same effect. These findings contribute to a better understanding and improvement of workspaces, enhancing users’ experience and well-being.

ObjectivesThis paper aims to study the free vibration characteristics of complicated shape plate coupled with fluid under elastic boundary conditions. MethodsTo this end, the rectangular domain enveloping the complicated shape plate domain is selected, and the plate displacement is expressed by the improved Fourier series in the rectangular domain. Combined with the Rayleigh integral, the relationship between the plate displacement and the surface sound pressure is established, and the integral formula is transformed into polar coordinates to avoid singularity. Aiming at the problem that it is difficult to obtain the explicit expression of the boundary curve in the variable limit integral in local polar coordinates, the structural boundary curves are treated by "replacing curve with straight" to simplify the Rayleigh integral. Based on the energy principle, a semi analytical method for analyzing the free vibration characteristics of complicated shape plate contacting with water on one side is established. ResultsThe numerical examples of rectangular plate, circular plate and some complicated shape plates are given. Compared with the finite element method and literature results, the convergence and accuracy of the method are verified, and the influence of elastic boundary conditions on the added virtual mass incremental (AVMI) factor of plate is discussed. The AVMI factor of each mode reaches the maximum near the dimensionless displacement spring stiffness of 103. At this time, the structure is relatively most affected by the fluid. ConclusionsThis method has strong adaptability and high calculation efficiency. It reveals the free vibration law of complicated shape plate coupled with fluid, and has certain engineering guiding significance.

Purpose: Given the COVID-19 pandemic, many Objective Structured Clinical Examinations (OSCEs) have been adapted to virtual formats without addressing whether physical examination maneuvers can or should be assessed virtually. In response, we developed a novel touchless physical examination station for a virtual OSCE and gathered validity evidence for its use. Methods: A touchless physical examination OSCE station was pilot-tested in a virtual OSCE in which Internal Medicine residents were asked to verbalize their approach to the physical examination, interpret images and videos of findings provided upon request, and make a diagnosis. Differences in performance by training year were explored using ANOVA. In addition, data were analyzed based on a modified approach of Bloom's taxonomy of learning: knowledge, understanding, and synthesis. Results: Sixty-seven residents (PGY1-3) participated in the OSCE. Scores on the pilot station were significantly different between training levels (F=3.936, p=0.024, ηp2=0.11). The pilot station-total correlation (STC) was 0.558, and the item-station correlations (ITC) ranged from 0.115 to 0.571, with the most discriminating items being those that assessed higher orders of learning (understanding and synthesis). Conclusion: This touchless physical examination station was feasible, had acceptable psychometric characteristics, and discriminated between residents at different levels of training.

To address the problem of tribological failure in an aircraft piston pump valve plate pair, the friction and wear properties of the valve plate pair materials (W9Mo3Cr4V-HAl61-4-3-1) of an axial piston pump at a certain speed and load were studied using a disc-ring tester under lubrication with No. 15 aviation hydraulic oil. The results show that the friction coefficient (COF) fluctuated in the range of 0.019~0.120 when the load (L) increased from 30 N to 120 N, and the speed increased from 100 r/min to 500 r/min. With the increase in the rotational speed, the COF of the valve plate pair decreased first and then increased. When the rotation speed (V) was 300 r/min, the relative COF was the smallest. Under L lower than 60 N, abrasive wear was the main wear mechanism. Under L higher than 90 N, the main wear mechanism was adhesive wear but mild oxidation wear also occurred. In addition, based on the V, L, radius (R), and test duration (T), which affected COF, the random forest regression (RFR) algorithm, the bagging regression (BR) algorithm, and the extra trees regression (ETR) algorithm were used as machine learning methods to predict the COF of the valve plate pair. Mean absolute error (MAE), root mean square error (RMSE), and coefficient of determination (R2) were used to evaluate its performance, with the results showing that the ETR prediction model was the best method for predicting COF. The results of the machine learning also showed that the contributions of V, L, R, and T were 43.56%, 36.76%, 13.13%, and 6.55%, respectively, indicating that V had the greatest influence on the COF of the W9Mo3Cr4V/HAl61-4-3-1 friction pair. This study is expected to provide support for the rapid development of new valve plate pair materials.

To reduce the influence of the permanent magnet (PM) installation error on the electromagnetic characteristics of the outer rotor permanent magnet synchronous motor (OPMSM), the rotor structure of the OPMSM is optimized in this paper. The optimization method of adding auxiliary teeth on the surface of the rotor core is studied, and the influence of different auxiliary teeth heights on the electromagnetic performance of OPMSM is analyzed. It is found that adding auxiliary teeth with suitable height can greatly reduce the installation error of the PM, increase the mechanical stability of the motor, and ensure that the electromagnetic characteristics of the motor remain at a good level. Firstly, the topology and parameters of the motor proposed in this paper are introduced and analyzed. Secondly, the influence of PM installation error on the electromagnetic performance of the motor is analyzed based on the finite element method (FEM), and the necessity of eliminating PM installation error is demonstrated. Then, the parametric scanning method is used to analyze the influence of auxiliary teeth height change on the electromagnetic performance of the motor, and the selection standard of the optimal auxiliary teeth height is determined. By comparing and analyzing OPMSM with different sizes and different pole–slot ratios, the universality of the conclusions is demonstrated.

For permanent magnet (PM) machines, analysis of armature magnetic field (AMF) plays an essential role in the qualitative analysis of machine operation principle, quantitative calculation of machine electromagnetic performance, further optimization or innovation of the machine, and so on. The winding configuration determines the primitive armature magnetomotive force (MMF), which greatly influences the AMF. In this paper, the AMF analytical model of slotless PM machines with arbitrary-phase equidirectional toroidal winding (EDTW) is derived, and the harmonic characteristics of the AMF are analyzed. Firstly, the expression of the arbitrary-phase EDTW primitive armature MMF is derived, and the band factor is introduced to represent the influence of coil bandwidth on the MMF. Secondly, the AMF analytical model is derived by introducing the concept of ideal air-gap permeability density, and the harmonic characteristics of the AMF are analyzed. Finally, taking 3, 4, 5, and 6-phase EDTW as examples, the relevant conclusions obtained by the analytical method (AM) are compared with those obtained by the finite element method (FEM). The comparison results show good consistency, confirming the accuracy and effectiveness of the AM. The relevant conclusions of this paper can provide a reference for the further research and application of the EDTW.

ObjectivesDue to the larger length-to-diameter ratio of the stern bearing, it is difficult to reflect its actual operating conditions when simplified to the traditional equivalent model of single-point support. Therefore, the influence of the equivalent form of the stern bearing on the transverse vibration characteristics of the shafting is investigated.MethodsThe improved Fourier series is introduced to describe the lateral vibration displacement of propulsion shafting. Then, the calculation model of lateral vibration performance of propulsion shafting under various equivalent forms, such as single-point support, multi-point support or continuous distributed support, are constructed based on the energy principle. Thereby, the influence of the change of support stiffness equivalent to the liquid film pressure on the lateral vibration of the shafting and the influence of the propeller excitation on the vibration response of the shafting are further analyzed. Finally, the results acquired by the proposed model is compared with the results of related references and finite element method (FEM) to verify the validity of the calculation model.ResultsThe multi-point support calculation results converge to the continuous distributed support calculation results. The three-point support equivalent form can be used to study the influence of liquid film pressure distribution on the lateral vibration characteristics of the propulsion shafting. The shafting response under propeller excitation is affected by the revolution speed.Conclusions The research indicates that three-point support equivalent form can be used to analyze the influence of liquid film pressure on the shafting lateral vibration performance. The proposed model in this paper has advantages of good convergence, high accuracy, and less cost-consuming.

Abstract Background With the rapid accumulation of scRNA-seq data, more and more automatic cell type identification methods have been developed, especially those based on deep learning. Although these methods have reached relatively high prediction accuracy, many issues still exist. One is the interpretability. The second is how to deal with the non-standard test samples that are not encountered in the training process. Results Here we introduce scCapsNet-mask, an updated version of scCapsNet. The scCapsNet-mask provides a reasonable solution to the issues of interpretability and non-standard test samples. Firstly, the scCapsNet-mask utilizes a mask to ease the task of model interpretation in the original scCapsNet. The results show that scCapsNet-mask could constrain the coupling coefficients, and make a one-to-one correspondence between the primary capsules and type capsules. Secondly, the scCapsNet-mask can process non-standard samples more reasonably. In one example, the scCapsNet-mask was trained on the committed cells, and then tested on less differentiated cells as the non-standard samples. It could not only estimate the lineage bias of less differentiated cells, but also distinguish the development stages more accurately than traditional machine learning models. Therefore, the pseudo-temporal order of cells for each lineage could be established. Following these pseudo-temporal order, lineage specific genes exhibit a gradual increase expression pattern and stem cell associated genes exhibit a gradual decrease expression pattern. In another example, the scCapsNet-mask was trained on scRNA-seq data, and then used to assign cell type in spatial transcriptomics that may contain non-standard sample of doublets. The results show that the scCapsNet-mask not only restored the spatial map but also identified several non-standard samples of doublet. Conclusions The scCapsNet-mask offers a suitable solution to the challenge of interpretability and non-standard test samples. By adding a mask, it has the advantages of automatic processing and easy interpretation compared with the original scCapsNet. In addition, the scCapsNet-mask could more accurately reflect the composition of non-standard test samples than traditional machine learning methods. Therefore, it can extend its applicability in functional analysis, such as fate bias prediction in less differentiated cells and cell type assignment in spatial transcriptomics.

Oil is an important strategic material and civil energy. Accurate prediction of oil consumption can provide basis for relevant departments to reasonably arrange crude oil production, oil import and export, and optimize the allocation of social resources. Therefore, a new grey model FENBGM(1,1) is proposed to predict oil consumption in China. Firstly, the grey effect of the traditional GM(1,1) model was transformed into a quadratic equation. Four different parameters were introduced to improve the accuracy of the model, and the new initial conditions were designed by optimizing the initial values by weighted buffer operator. Combined with the reprocessing of the original data, the scheme eliminates the random disturbance effect, improves the stability of the system sequence, and can effectively extract the potential pattern of future development. Secondly, the cumulative order of the new model was optimized by fractional cumulative generation operation. At the same time, the smoothness rate quasi-smoothness condition was introduced to verify the stability of the model, and the particle swarm optimization algorithm (PSO) was used to search the optimal parameters of the model to enhance the adaptability of the model. Based on the above improvements, the new combination prediction model overcomes the limitation of the traditional grey model and obtains more accurate and robust prediction results. Then, taking the petroleum consumption of China's manufacturing industry and transportation, storage and postal industry as an example, this paper verifies the validity of FENBGM(1,1) model, analyzes and forecasts China's crude oil consumption with several commonly used forecasting models, and uses FENBGM(1,1) model to forecast China's oil consumption in the next four years. The results show that FENBGM(1,1) model performs best in all cases. Finally, based on the prediction results of FENBGM(1,1) model, some reasonable suggestions are put forward for China's oil consumption planning.

Abstract In terms of the characteristics of multi‐objective and interactions among optimization objectives of the tubular permanent magnet linear generator with 120° phase belt toroidal winding (120°‐TPMLG), a multi‐objective optimization method is proposed to improve the generators performances, which is based on the combination of response surface method and the genetic algorithm. First, the sensitivity analysis of different structural parameters on the performances of the 120°‐TPMLG is conducted to pick out the sensitive structural parameters. Then develop those sensitive parameters as optimization variables to establish the response surface equation of the generator performances including output power (P), detent force (F), and the efficiency (η). Subsequently, based on the surface equation, the genetic algorithm (GA) fitness function is proposed to conducted the global optimization and the optimization results are finally obtained. To verify the effectiveness of the proposed optimization method, the performances of the optimal 120°‐TPMLG are analysed and compared with the initial one. The results show that the performances including the detent force and power density of the 120°‐TPMLG are greatly improved, which prove that the proposed multi‐objective optimization method is effective for the 120°‐TPMLG.

Abstract The three‐phase permanent magnet synchronous motor (three‐phase PMSM) has gained much popularity in many applications due to its various advantages. In addition, due to the good fault tolerance, simple inverter circuit structure and high torque density, the six‐phase PMSM has better prospects than three‐phase PMSM in biomedical devices, electric vehicles and other fields with high reliability requirements. In this study, a six‐phase axial‐flux PMSM inherently without cogging torque is proposed to improve torque density, which equips the 60° phase‐belt toroidal winding (60°TW) and slotless stator core. Based on the same effective volume, permanent magnet material, power grade and the other major motor parameters, two six‐phase PMSMs with 30° phase‐belt toroidal winding (30°TW) and 60°TW are designed, respectively. The armature reaction field, air gap magnetic density, back‐electromotive force, output torque, loss characteristic and torque‐speed characteristic are compared by using three‐dimensional (3D) finite‐element models in detail. Finally, the experimental test is carried out using the prototype of three‐phase PMSM with 120° phase‐belt toroidal winding. The experimental results indirectly verify the feasibility of 60° phase‐belt toroidal winding and correctness of 3D FEM. The 3D FEM analysis results are presented to show that torque density of the proposed six‐phase PMSM with 60°TW is improved in comparison to the six‐phase PMSM with 30°TW. Index Terms—60° phase‐belt toroidal winding, axial flux, six‐phase permanent magnet synchronous motor, torque density

The current shape memory alloys (SMA) constitutive models have the problems of complicated calculation, inaccurate results, measuring difficult parameters, and inconvenient application, which brings about challenges for designing, analyzing, and simulating SMA’s macroscopic behavior in engineering. This paper proposed practical SMA constitutive models for accurate engineering calculation, which apply to both the single loading-unloading process and the multiple loading-unloading cycles. The more accurate SMA theoretical tensile curve and temperature-stress phase transformation diagram is introduced to derive the constitutive model. The more accurate calculation method of elastic modulus, phase transformation modulus, and critical phase transformation stress is proposed in this paper. The proposed constitutive model considers the incomplete phase transformation phenomenon and the variation of critical phase transformation stress under multiple loading and unloading conditions. It can accurately evaluate the critical phase transformation stress and stress-strain relationships at various temperatures. Tensile tests under various working conditions were conducted. The results demonstrated that the proposed constitutive model could well simulate the SMA’s macroscopic mechanical behavior at various temperatures, loads, and multiple loading-unloading cycles with accuracy, practicality, and efficiency.

The latest progresses of experimental biology have generated a large number of data with different formats and lengths. Deep learning is an ideal tool to deal with complex datasets, but its inherent “black box” nature needs more interpretability. At the same time, traditional interpretable machine learning methods, such as linear regression or random forest, could only deal with numerical features instead of modular features often encountered in the biological field. Here, we present MultiCapsNet (https://github.com/wanglf19/MultiCapsNet), a new deep learning model built on CapsNet and scCapsNet, which possesses the merits such as easy data integration and high model interpretability. To demonstrate the ability of this model as an interpretable classifier to deal with modular inputs, we test MultiCapsNet on three datasets with different data type and application scenarios. Firstly, on the labeled variant call dataset, MultiCapsNet shows a similar classification performance with neural network model, and provides importance scores for data sources directly without an extra importance determination step required by the neural network model. The importance scores generated by these two models are highly correlated. Secondly, on single cell RNA sequence (scRNA-seq) dataset, MultiCapsNet integrates information about protein-protein interaction (PPI), and protein-DNA interaction (PDI). The classification accuracy of MultiCapsNet is comparable to the neural network and random forest model. Meanwhile, MultiCapsNet reveals how each transcription factor (TF) or PPI cluster node contributes to classification of cell type. Thirdly, we made a comparison between MultiCapsNet and SCENIC. The results show several cell type relevant TFs identified by both methods, further proving the validity and interpretability of the MultiCapsNet.

Nitrile-butadiene rubber (NBR) with different acrylonitrile contents were eroded by quartz slurry using a self-made erosion testing apparatus to study the erosion wear behavior. Quartz slurry with a concentration of 33 wt.% was used to impact the specimen surface at 45° sample angle. The experimental data, such as erosion rate, hardness and swelling increment were compared and analyzed. The morphologies of worn surfaces were characterized using the field emission scanning electron microscopy to reveal the wear mechanism. The results showed that the acrylonitrile content in the molecular chains had a significant effect on the erosion performance of NBR. Furthermore, a static swelling test was conducted as a contrast experiment to investigate the effect of erosion on the swelling behavior of rubber surface. By comparing the results it could be found that the dynamic swelling increment during the erosion test was almost four or five times larger than that of static swelling. Mechanism of the interaction between swelling and erosion was also discussed.

Based on the principle of energy variation, an improved Fourier series is introduced as an allowable displacement function. This paper constructs a calculation model that can study the in-plane and out-of-plane free and forced vibrations of curved beam structures under different boundary conditions. Firstly, based on the generalized shell theory, considering the shear and inertial effects of curved beam structures, as well as the coupling effects of displacement components, the kinetic energy and strain potential energy of the curved beam are obtained. Subsequently, an artificial spring system is introduced to satisfy the constraint condition of the displacement at the boundary of the curved beam, obtain its elastic potential energy, and add it to the system energy functional. Any concentrated mass point or concentrated external load can also be added to the energy function of the entire system with a corresponding energy term. In various situations including classical boundary conditions, the accuracy and efficiency of the method in this paper are proved by comparing with the calculation results of FEM. Besides, by accurately calculating the vibration characteristics of common engineering structures like slow curvature (whirl line), the wide application prospects of this method are shown.

Double-sided permanent magnet linear synchronous machine with 120° phase belt toroidal windings (120°-TWDSPMLSM) suffers from large detent force due to the end effect and slot effect. Many existing methods can reduce the detent force of the 120°-TWDSPMLSM effectively. But they also minimize the back electromotive force (back-EMF) and thrust simultaneously. To alleviate this problem, this paper adopts a method of combining slot-shift structure with rearranging the 120° phase belt toroidal windings (120°-TW) to suppress the detent force and improve the back-EMF and thrust of the 120°-TWDSPMLSM simultaneously. First, the slots on the two sides of the primary part are stagger by an optimal distance to reduce the detent force. The models of the detent force, including the end force and cogging force, is established theoretically, and then verified by finite-element analysis (FA). Then, the 120°-TW are rearranged to improve the back-EMF and average thrust. And the electromagnetic characteristics of the 120°-TWDSPMLSM under different shifted distances are analyzed and compared in detail. Finally, the result shows that the detent force of optimized machine is 70.19% lower than that of the original machine, and the thrust fluctuation reduces 19.21%. Besides, the back-EMF of optimized machine is 6.84% lower than that of the original machine, but 31.86 higher than the machine with shifting slots and without rearranging the 120°-TW. Therefore, the optimal method in this paper is available in the detent force reduction and thrust improvement of the 120°-DSPMLSM.

Telenomus remus (Nixon) is a dominant egg parasitoid of the destructive agricultural pest Spodoptera frugiperda (J. E. Smith), and so is used in augmentative biocontrol programs in several countries. An optimized mass-rearing system is essential to produce biological control products in a timely and cost-effective manner. In this study, the photoperiod, host egg:parasitoid ratio, and exposure time were evaluated to identify the optimal rearing conditions for T. remus on the alternative host Spodoptera litura (Fabricius) eggs. Results showed that increasing photoperiod above 12L:12D remarkably improved parasitoid progeny yield and life table parameters. Overlong photoperiods shortened female longevity, but within acceptable limits. There was a significant negative correlation between parasitism rate and host egg:parasitoid ratio under exposure times of 12 and 36 h, but not 24 h. Percentage of female progeny increased significantly along with increasing the host egg:parasitoid ratio. A significant negative relationship between the number of emerged adults per egg and the host egg:parasitoid ratio was observed at an exposure time of 36 h. It was concluded that T. remus may be mass-reared most efficiently on S. litura eggs using a photoperiod of more than 12L:12D, a 14–20:1 host egg:parasitoid ratio, and an exposure time of 24 h. These findings can be used to produce T. remus more efficiently and at lower costs.

Based on the principle of energy variation, a calculation model for the free vibration characteristics of a cylindrical shell with a finite submerged depth considering the influence of the free liquid surface is established in this paper. First, the Euler beam function is used instead of the shell axial displacement function to obtain the shell kinetic energy and potential energy. Then, by using the mirror image method, the analytical expression of the fluid velocity potential considering the free surface is obtained, and the flow field is added to the system energy functional in the form of fluid work. Then the energy functional is changed to obtain the shell–liquid coupled vibration equation. Solving the equation can obtain the natural frequencies and modes of the structure. The comparison with the finite element calculation results verifies the accuracy of the calculation model in this paper. The research on the influence of the free liquid surface shows that compared to the infinite domain, the free liquid surface destroys the symmetry of the entire system, resulting in a difference in the natural frequency of the positive and negative modes of the shell, and the circumferential mode shapes are no longer mutually uncoupled trigonometric functions. The existence of free liquid surface will also increase the natural frequency of the same order mode, and the closer to the free surface, the natural frequency is greater. As the immersion depth increases, the free vibration characteristics will quickly tend to the result of infinite domain. Additionally, when the immersion depth is equal to or greater than four times the radius of the shell structure, it can be considered that the free liquid surface has no effect. These law and phenomena have also been explained from the mechanism. The method in this paper provides a new analytical solution pattern for solving this type of problem.

The utilization of position sensor reduces the system reliability of switched reluctance motor (SRM), especially in harsh environments. It also increases the complexity of the system. Therefore, the research on sensorless control has become one of the hot spots in recent years. Comparing with the existing sensorless control technology, the new method exploring the sensorless control of double-sided linear switched reluctance motor (DLSRM) shows the following advantages:1)high accuracy , and 2) good practicability. Based on the new proposed method, the DLSRM speed controller is augmented with the peak current method and the voltage chopping closed-loop speed control. Moreover, the winding resistance in the equation is corrected according to the integral flux linkage when the phase current is zero. The accuracy and feasibility of the simplified flux linkage method in estimating the position of the DLSRM is verified.

Multimotors traction is a common driving mode for electric locomotives. The complexity and variability of the operating environment often cause difficulties for one or some traction motors to output the distributed traction torque, which requires the redistribution of the torque output of multimotors to maintain the total traction torque of all motors at a given constant. To this end, a multimotors coordination control method was proposed for consistent total traction torque of electric locomotives. Through this approach, a traction torque-coordinated control structure was constructed on the basis of energy minimisation with an optimal dynamic adjustment mode. The sliding mode tracking control was developed for each independent motor to improve its dynamic response performance. A simulation verification of motors fault types in two different cases was conducted. The results showed that the proposed method could track the total traction torque in a short time, and the system fluctuations in independent motor coordination process were very small.

Building integrated photovoltaic (BIPV) is one of the most efficient ways to utilize renewable energy in buildings. However, the stochastic characteristic of PV power generation and load challenges the optimal dispatch of the BIPV. This paper proposes an optimal scheduling strategy of BIPV microgrid considering virtual energy storage (VES), which intends to further improve the operating economy of a BIPV microgrid. Firstly, existing research findings and gaps in this research area were analyzed. Then, the mathematical model of each unit in the system was created, meanwhile, the air conditioner-based VES (ACVES) model and electric water heater-based VES (EWHVES) model are built by exploiting the heat/cold storage capability of building and the electric water heater, respectively. Next, the optimal scheduling model considering the VES is designed. Finally, the optimal scheduling model is solved by CPLEX to obtain the optimal scheduling strategy that reduces the operating cost of the system. Simulation results demonstrate that the proposed strategy can reduce the operating cost of the system. Furthermore, the VES shows the potential to replace the battery energy storage system.

When nitrile rubber contacting with water under the external force during the service life, swelling and sliding wear occur. Since nitrile has similar polarity to water, the interaction between water and nitrile rubber and its influence on mechanical and tribological behaviors of the nitrile rubber play an important role in rubber performance, which is extremely necessary to be studied systematically. In this study, immersion experiments were conducted on three nitrile rubber samples which contained different acrylonitrile weight percentages of 18%, 26% and 41% (i.e. N18, N26, and N41) respectively. The hardness, tensile, dry and wet unidirectional sliding wear tests were further conducted. To reveal the mechanisms, the nuclear magnetic resonance (NMR) analysis and scanning electron microscopy (SEM) analysis were performed and interpreted accordingly. The results showed that cross-linking break based structural damage, substance dissolution and surface layer defects occurred after swelling, resulting in decreases in hardness and tensile strength and increases in permanent deformation fracture rates of the nitrile rubbers. The friction coefficient value of the un-swollen NBRs was positively related to the wear loss and decreased with the increase of the acrylonitrile content. During the wear process under dry conditions, the un-swollen rubbers presented hardening in aging while the swollen samples softened along with the deterioration of adhesive wear with higher steady-state friction coefficient value and wear loss. Under wet friction conditions, the susceptible wear behavior of the swollen rubbers induced reductions in friction coefficient and increases in wear loss. The swelling degree and its effects on mechanical and tribological behavior decreased with the increase of the acrylonitrile content. The swelling influences on the tribological behavior of nitrile rubber affected and acted on the entire wear process.

The high-speed permanent magnet synchronous motor (HSPMSM) plays an important role in a wide range of engineering fields due to its high power density, high efficiency, and light weight. In this paper, a HSPMSM equipped with in-line slot conductors (I-LSC) is proposed and compared with one equipped with equidirectional toroidal winding (ETW). Firstly, the differences between them are revealed, including topology, back-electromotive force (EMF), slot fill factor, copper loss, and torque. Secondly, two-dimensional finite element method (2D-FEM) tools are used to obtain more precise performance such as air-gap field, back-EMF, torque characteristics, efficiency maps, and the unbalanced magnetic force (UMF). Considering the endwindings of copper loss of ETW and the end ring copper loss of I-LSC, the losses and efficiency of two motors are simulated by three-dimensional finite element method (3D-FEM). Finally, the simulation results validate the feasibility of the newly proposed winding and indicate that in-line slot conductors have superiority in power density due to the high slot fill factor. [ABSTRACT FROM AUTHOR]