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The chromosome-level genome of double-petal phenotype jasmine provides insights into the biosynthesis of floral scent 被引量:1
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作者 Xiangyu Qi Huadi Wang +7 位作者 Shuyun Liu Shuangshuang Chen Jing Feng Huijie Chen Ziyi Qin Quanming Chen Ikram Blilou Yanming Deng 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第1期259-272,共14页
Jasmine(Jasminum sambac Aiton)is a well-known cultivated plant species for its fragrant flowers used in the perfume industry and cosmetics.However,the genetic basis of its floral scent is largely unknown.In this study... Jasmine(Jasminum sambac Aiton)is a well-known cultivated plant species for its fragrant flowers used in the perfume industry and cosmetics.However,the genetic basis of its floral scent is largely unknown.In this study,using PacBio,Illumina,10×Genomics and highthroughput chromosome conformation capture(Hi-C)sequencing technologies,a high-quality chromosome-level reference genome for J.sambac was obtained,exploiting a double-petal phenotype cultivar‘Shuangbanmoli’(JSSB).The results showed that the final assembled genome of JSSB is 580.33 Mb in size(contig N50=1.05 Mb;scaffold N50=45.07 Mb)with a total of 39618 predicted protein-coding genes.Our analyses revealed that the JSSB genome has undergone an ancient whole-genome duplication(WGD)event at 91.68 million years ago(Mya).It was estimated that J.sambac diverged from the lineage leading to Olea europaea and Osmanthus fragrans about 28.8 Mya.On the basis of a combination of genomic,transcriptomic and metabolomic analyses,a range of floral scent volatiles and genes were identified involved in the benzenoid/phenylpropanoid and terpenoid biosynthesis pathways.The results provide new insights into the molecular mechanism of its fragrance biosynthesis in jasmine. 展开更多
关键词 Jasminum sambac Aiton OLEACEAE Genome evolution floral scent Terpene synthase
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Intraspecific floral colour variation in three Pedicularis species
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作者 Qiu-Yu Zhang Zhe Chen +1 位作者 Hang Sun Yang Niu 《Plant Diversity》 SCIE CAS CSCD 2024年第2期274-279,共6页
Flower constancy describes the phenomenon that pollinators tend to successively visit flowers of a single species during foraging,reducing reproductive interference in natural communities.The extent of flower constanc... Flower constancy describes the phenomenon that pollinators tend to successively visit flowers of a single species during foraging,reducing reproductive interference in natural communities.The extent of flower constancy is largely determined by the floral traits of co-flowering species.Both higher inter-specific and lower intraspecific differences of floral traits should contribute to a higher level of flower constancy.However,previous studies mainly focused on interspecific difference,and the intraspecific variation(consistency)of floral traits received much less attention.We hypothesise that selection may favour lower intraspecific floral trait variation in communities composed of multiple co-flowering congeners.We investigated the floral colour variation of three focal Pedicularis species that share pollinators in 19communities composed of either single or multiple Pedicularis species.Colour was quantified using image-based colour analysis as perceived by pollinators.We found that most of the intrapopulation floral colour variation was below the colour discrimination threshold of bumblebees,implying strongly constrained by the visual selection by pollinators.Contrary to the hypothesis,there is no significant difference in intraspecific floral colour variation between different community contexts.It may be due to the relatively large interspecific floral colour differences of most co-flowering species.The influence of community context on intraspecific variation may be reflected in floral traits other than colours. 展开更多
关键词 Flower constancy floral colour variation Plantepollinator interactions Pollinator vision
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Analytical Model and Topology Optimization of Doubly-fed Induction Generator
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作者 Lu Sun Haoyu Kang +4 位作者 Jin Wang Zequan Li Jianjun Liu Yiming Ma Libing Zhou 《CES Transactions on Electrical Machines and Systems》 EI CSCD 2024年第2期162-169,共8页
As the core component of energy conversion for large wind turbines,the output performance of doubly-fed induction generators (DFIGs) plays a decisive role in the power quality of wind turbines.To realize the fast and ... As the core component of energy conversion for large wind turbines,the output performance of doubly-fed induction generators (DFIGs) plays a decisive role in the power quality of wind turbines.To realize the fast and accurate design optimization of DFIGs,this paper proposes a novel hybriddriven surrogate-assisted optimization method.It firstly establishes an accurate subdomain model of DFIGs to analytically predict performance indexes.Furthermore,taking the inexpensive analytical dataset produced by the subdomain model as the source domain and the expensive finite element analysis dataset as the target domain,a high-precision surrogate model is trained in a transfer learning way and used for the subsequent multi-objective optimization process.Based on this model,taking the total harmonic distortion of electromotive force,cogging torque,and iron loss as objectives,and the slot and inner/outer diameters as parameters for optimizing the topology,achieve a rapid and accurate electromagnetic design for DFIGs.Finally,experiments are carried out on a 3MW DFIG to validate the effectiveness of the proposed method. 展开更多
关键词 Doubly-fed induction generators Accurate subdomain model Surrogate-assisted Transfer learning
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A Loss-model-based Efficiency Optimization Control Method for Induction Traction System of High-speed Train under Emergency Self-propelled Mode
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作者 Yutong Zhu Yaohua Li 《CES Transactions on Electrical Machines and Systems》 EI CSCD 2024年第2期227-239,共13页
Increasing attention has been paid to the efficiency improvement of the induction traction system of high-speed trains due to the high demand for energy saving. In emergency self-propelled mode, however, the dc-link v... Increasing attention has been paid to the efficiency improvement of the induction traction system of high-speed trains due to the high demand for energy saving. In emergency self-propelled mode, however, the dc-link voltage and the traction power of the motor are significantly reduced, resulting in decreased traction efficiency due to the low load and low speed operations. Aiming to tackle this problem, a novel efficiency improved control method is introduced to the emergency mode of high-speed train traction system in this paper. In the proposed method, a total loss model of induction motor considering the behaviors of both iron and copper loss is established. An improved iterative algorithm with decreased computational burden is then introduced, resulting in a fast solving of the optimal flux reference for loss minimization at each control period. In addition, considering the parameter variation problem due to the low load and low speed operations, a parameter estimation method is integrated to improve the controller's robustness. The effectiveness of the proposed method on efficiency improvement at low voltage and low load conditions is demonstrated by simulated and experimental results. 展开更多
关键词 Efficiency optimization induction motor Loss model control Motor drives Traction system
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A Stable Fuzzy-Based Computational Model and Control for Inductions Motors
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作者 Yongqiu Liu Shaohui Zhong +3 位作者 Nasreen Kausar Chunwei Zhang Ardashir Mohammadzadeh Dragan Pamucar 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期793-812,共20页
In this paper,a stable and adaptive sliding mode control(SMC)method for induction motors is introduced.Determining the parameters of this system has been one of the existing challenges.To solve this challenge,a new se... In this paper,a stable and adaptive sliding mode control(SMC)method for induction motors is introduced.Determining the parameters of this system has been one of the existing challenges.To solve this challenge,a new self-tuning type-2 fuzzy neural network calculates and updates the control system parameters with a fast mechanism.According to the dynamic changes of the system,in addition to the parameters of the SMC,the parameters of the type-2 fuzzy neural network are also updated online.The conditions for guaranteeing the convergence and stability of the control system are provided.In the simulation part,in order to test the proposed method,several uncertain models and load torque have been applied.Also,the results have been compared to the SMC based on the type-1 fuzzy system,the traditional SMC,and the PI controller.The average RMSE in different scenarios,for type-2 fuzzy SMC,is 0.0311,for type-1 fuzzy SMC is 0.0497,for traditional SMC is 0.0778,and finally for PI controller is 0.0997. 展开更多
关键词 Sliding mode control self-tuning type-2 fuzzy systems inductions motor parameters uncertainty
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Coupled Numerical Simulation of Electromagnetic and Flow Fields in a Magnetohydrodynamic Induction Pump
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作者 He Wang Ying He 《Fluid Dynamics & Materials Processing》 EI 2024年第4期889-899,共11页
Magnetohydrodynamic(MHD)induction pumps are contactless pumps able to withstand harsh environments.The rate of fluid flow through the pump directly affects the efficiency and stability of the device.To explore the inf... Magnetohydrodynamic(MHD)induction pumps are contactless pumps able to withstand harsh environments.The rate of fluid flow through the pump directly affects the efficiency and stability of the device.To explore the influence of induction pump settings on the related delivery speed,in this study,a numerical model for coupled electromagnetic and flow field effects is introduced and used to simulate liquid metal lithium flow in the induction pump.The effects of current intensity,frequency,coil turns and coil winding size on the velocity of the working fluid are analyzed.It is shown that the first three parameters have a significant impact,while changes in the coil turns have a negligible influence.The maximum increase in working fluid velocity within the pump for the parameter combination investigated in this paper is approximately 618%.As the frequency is increased from 20 to 60 Hz,the maximum increase in the mean flow rate of the working fluid is approximately 241%.These research findings are intended to support the design and optimization of these devices. 展开更多
关键词 Magnetic fluid multi-physical field coupling induction pump numerical simulation liquid metal conveying
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Harmonics in the Squirrel Cage Induction Motor Analytic Calculation Part III: Influence on the Torque-speed Characteristic
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作者 G.Kovács 《CES Transactions on Electrical Machines and Systems》 EI CSCD 2024年第1期86-102,共17页
The harmonics that appear in the squirrel cage asynchronous machine have been discussed in great detail in the literature for a long time. However, the systematization of the phenomenon is still pending, so we made an... The harmonics that appear in the squirrel cage asynchronous machine have been discussed in great detail in the literature for a long time. However, the systematization of the phenomenon is still pending, so we made an attempt to fill this gap in the previous parts of our study by elaborating formulas for calculation of parasitic torques. It was a general demand among those who work in this field towards the author to verify his formulas with measurements. In the literature, it seems,only one detailed, purposeful series of measurements has been published so far, the purpose of which was to investigate the effect of the number of rotor slots on the torque-speed characteristic curve of the machine. The main goal of this study is to verify the correctness of the formulas by comparing them with the referred series of measurements. Relying on this, the expected synchronous parasitic torques were developed for the frequently used rotor slot numbers-as a design guide for the engineer.Thus, together with our complete table for radial magnetic pull published in our previous work, the designer has all the principles, data and formulas available for the right number of rotor slots for his given machine and for the drive system. This brings this series of papers to an end. 展开更多
关键词 Asynchronous parasitic torques induction motor Squirrel cage rotor Space harmonics Synchronous parasitic torques
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Is Induction of Labor with Early Rupture of Membranes Associated with an Increased Rate of Clinical Chorioamnionitis?
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作者 Laura Rankin Matthew Romagano +1 位作者 Shauna Williams Joseph Apuzzio 《Open Journal of Obstetrics and Gynecology》 2024年第2期240-249,共10页
Objective: The objective of this study was to determine if early rupture of membranes (ROM) in women undergoing induction of labor (IOL) at term is associated with an increased rate of clinical chorioamnionitis. Study... Objective: The objective of this study was to determine if early rupture of membranes (ROM) in women undergoing induction of labor (IOL) at term is associated with an increased rate of clinical chorioamnionitis. Study Design: A retrospective cohort study was performed on women undergoing IOL. Early ROM was defined as ROM at a modified Bishop score less than 5, cervical dilation less than 4 cm, or cervical effacement less than 80%. The rate of clinical chorioamnionitis was compared between women with early and late ROM. Results: The rate of clinical chorioamnionitis was 8.6% (24/279). ROM at an effacement of less than 80% was associated with a rate of clinical chorioamnionitis of 15.4% (12/78) compared to 6.0% (12/201) at an effacement of equal to or greater than 80%, p = 0.017. The rate of cesarean delivery was higher for patients with early ROM by any definition: 32% compared to 17.5% by modified Bishop score (p = 0.031), 32.4% versus 18.2% by cervical dilation (p = 0.049), and 33.3% versus 14.9% by cervical effacement (p = 0.001). Conclusions: In patients undergoing IOL, early ROM may be associated with an increased rate of clinical chorioamnionitis when performed at a cervical effacement of less than 80% and an increased rate of cesarean delivery. 展开更多
关键词 Amniotomy Cesarean Delivery CHORIOAMNIONITIS induction of Labor Intraamniotic Infection Perinatal Infection Rupture of Membranes Term Pregnancy
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Enhanced Fuzzy Logic Control Model and Sliding Mode Based on Field Oriented Control of Induction Motor
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作者 Alaa Tahhan Feyzullah Temurtaş 《World Journal of Engineering and Technology》 2024年第1期65-79,共15页
In the context of induction motor control, there are various control strategies used to separately control torque and flux. One common approach is known as Field-Oriented Control (FOC). This technique involves transfo... In the context of induction motor control, there are various control strategies used to separately control torque and flux. One common approach is known as Field-Oriented Control (FOC). This technique involves transforming the three-phase currents and voltages into a rotating reference frame, commonly referred to as the “dq” frame. In this frame, the torque/speed and flux components are decoupled, allowing for independent control, by doing so, the motor’s speed can be regulated accurately and maintain a constant flux which is crucial to ensure optimal motor performance and efficiency. The research focused on studying and simulating a field-oriented control system using fuzzy control techniques for an induction motor. The aim was to address the issue of parameter variations, particularly the change in rotor resistance during motor operation, which causes the control system to deviate from the desired direction. This deviation implies to an increase in the magnetic flux value, specifically the flux component on the q-axis. By employing fuzzy logic techniques to regulate flux vector’s components in the dq frame, this problem was successfully resolved, ensuring that the magnetic flux value remains within the nominal limits. To enhance the control system’s performance, response speed, and efficiency of the motor, sliding mode controllers were implemented to regulate the current in the inner loop. The simulation results demonstrated the proficiency of the proposed methodology. 展开更多
关键词 induction Motor Vector Control Fuzzy Logic Control Sliding Mode
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The Absence of “Perfect Induction”in the Science
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作者 Corrado Giannantoni 《Journal of Applied Mathematics and Physics》 2024年第5期1930-1947,共18页
The present paper is finalized to show that the Science, even if considered in its two different Phenomenological Approaches at present known, is unable to assert that: “Thinks are like that”. This is because both t... The present paper is finalized to show that the Science, even if considered in its two different Phenomenological Approaches at present known, is unable to assert that: “Thinks are like that”. This is because both the two Scientific Approaches previously mentioned have not the property of “the perfect induction”. Consequently, although they can even reach an experimental confirmation of the theoretical results, and thus a “valid description” of the various phenomena of the surrounding world, such a description has not an “absolute value”. In fact, it always and only has an “operative validity”, that is, it exclusively and solely refers to an “experimental point of view”. This means that such an “operative validity” cannot represent the basis for a logical process characterized by a “perfect induction”. In addition, the Traditional Scientific Approach is also characterized by “Insoluble” Problems, “Intractable Problems”, Problems with “drifts”, which could generally be termed as “side effects”. On the other hand, the same com-possible Scientific Approach based on the Emerging Quality of Self-Organizing Systems, also presents its “Emerging Exits”. Consequently, none of the two mentioned scientific Approaches has the “gift” of “the perfect induction”. However, there are significant differences between the two. Differences that may “suggest” the most appropriate choice among them for an “operative point of view”. This conclusion will be com-proved by considering, with particular reference, both the “side effects”, which are related to the Traditional Approach and, on the other hand, the “Emerging Exits”, which specifically pertain to the new Scientific Approach based on the Emerging Quality of Self-Organizing Systems. 展开更多
关键词 Perfect induction Maximum Ordinality Principle Incipient Differential Calculus
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Microstructure and properties of induction brazing nickel base/WC composite coating 被引量:2
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作者 秦建 杨骄 +4 位作者 刘攀 刘大双 卢洪波 廖清泉 常云峰 《China Welding》 CAS 2023年第1期27-34,共8页
BNi-2/WC composite wear-resisting coating was prepared on carbon steel by the method of induction brazing.The microstructure and phase composition of the composite coating were analyzed,and the bonding strength and we... BNi-2/WC composite wear-resisting coating was prepared on carbon steel by the method of induction brazing.The microstructure and phase composition of the composite coating were analyzed,and the bonding strength and wear-resisting performance of the coating were tested.During the process of induction brazing,the tungsten carbide partially dissolves and reacts with the filler metal alloy to form NiW compound phase,which realizes the metallurgical combination of tungsten carbide and filler metal alloy.The matrix of the filler metal alloy consists of Ni solid solution and Ni_(3)B/Ni_(3)Si eutectic phase,and the metallurgical diffusion reaction occurs between the filler metal alloy and the steel matrix.The mechanical analysis results show that the self-strength of the composite coating reaches 140 MPa and the bonding strength of the filler metal alloy to the steel matrix reaches 360 MPa.The dry sand rubber wheel wear testing machine showed that the coating weight loss was only 0.2824 g,which was only 1/5 of the weight loss of 65 Mn matrix under the same conditions. 展开更多
关键词 composite coating induction brazing tungsten carbide BNI-2 wear resistance
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A finite volume method for global electromagnetic induction forward modeling on collocated unstructured grids 被引量:1
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作者 Liang Yin ZhengYong Ren +1 位作者 HongBo Yao Cong Yang 《Earth and Planetary Physics》 EI CSCD 2023年第1期57-65,共9页
Global electromagnetic induction provides an efficient way to probe the electrical conductivity in the Earth’s deep interior.Owing to the increasing geomagnetic data especially from high-accuracy geomagnetic satellit... Global electromagnetic induction provides an efficient way to probe the electrical conductivity in the Earth’s deep interior.Owing to the increasing geomagnetic data especially from high-accuracy geomagnetic satellites,inverting the Earth’s three-dimensional conductivity distribution on a global scale becomes attainable.A key requirement in the global conductivity inversion is to have a forward solver with high-accuracy and efficiency.In this study,a finite volume method for global electromagnetic induction forward modeling is developed based on unstructured grids.Arbitrary polyhedral grids are supported in our algorithms to obtain high geometric adaptability.We employ a cell-centered collocated variable arrangement which allows convenient discretization for complex geometries and straightforward implementation of multigrid technique.To validate the method,we test our code with two synthetic models and compare our finite volume results with an analytical solution and a finite element numerical solution.Good agreements are observed between our solution and other results,indicating acceptable accuracy of the proposed method. 展开更多
关键词 global electromagnetic induction mantle electrical conductivity finite volume method unstructured grids
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Modeling and small-signal stability analysis of doubly-fed induction generator integrated system 被引量:1
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作者 Tianming Gu Puyu Wang +3 位作者 Dingyuan Liu Ao Sun Dejian Yang Gangui Yan 《Global Energy Interconnection》 EI CSCD 2023年第4期438-449,共12页
Owing to their stability,doubly-fed induction generator(DFIG)integrated systems have gained considerable interest and are the most widely implemented type of wind turbines and due to the increasing escalation of the w... Owing to their stability,doubly-fed induction generator(DFIG)integrated systems have gained considerable interest and are the most widely implemented type of wind turbines and due to the increasing escalation of the wind generation penetration rate in power systems.In this study,we investigate a DFIG integrated system comprising four modules:(1)a wind turbine that considers the maximum power point tracking and pitch-angle control,(2)induction generator,(3)rotor/grid-side converter with the corresponding control strategy,and(4)AC power grid.The detailed small-signal modeling of the entire system is performed by linearizing the dynamic characteristic equation at the steady-state value.Furthermore,a dichotomy method is proposed based on the maximum eigenvalue real part function to obtain the critical value of the parameters.Root-locus analysis is employed to analyze the impact of changes in the phase-locked loop,short-circuit ratio,and blade inertia on the system stability.Lastly,the accuracy of the small-signal model and the real and imaginary parts of the calculated dominant poles in the theoretical analysis are verified using PSCAD/EMTDC. 展开更多
关键词 Doubly-fed induction generator(DFIG) Maximum power point tracking DICHOTOMY Small-signal stability
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Depleted uranium oxide supported nickel catalyst for autothermal CO_(2)methanation in non-adiabatic reactor under induction heating 被引量:1
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作者 Lai Truong-Phuoc Jean-Mario Nhut +7 位作者 Loïc Vidal Cuong Duong-Viet Sécou Sall Corinne Petit Christophe Sutter Mehdi Arab Alex Jourdan Cuong Pham-Huu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第10期310-323,I0010,共15页
Undoped nickel-based catalysts supported on depleted uranium oxide allow one to carry out CO_(2)methanation process under extremely low reaction temperature under atmospheric pressure and powered by a contactless indu... Undoped nickel-based catalysts supported on depleted uranium oxide allow one to carry out CO_(2)methanation process under extremely low reaction temperature under atmospheric pressure and powered by a contactless induction heating.By adjusting the reaction conditions,the catalyst is able to perform CO_(2)methanation reaction under autothermal process operated inside a non-adiabatic reactor,without any external energy supply.Such autothermal process is possible thanks to the high apparent density of the UO_x which allows one to confine the reaction heat in a small catalyst volume in order to confine the exothermicity of the reaction inside the catalyst and to operate the reaction at equilibrium heat in-heat out.Such autothermal operation mode allows one to significantly reduce the complexity of the process compared to that operated using adiabatic reactor,where complete insulation is required to prevent heat disequilibrium,in order to reduce as much as possible,the heat exchange with the external medium.The catalyst displays an extremely high stability as a function of time on stream as no apparent deactivation.It is expected that such new catalyst with unprecedented catalytic performance could open new era in the field of heterogeneous catalysis where traditional supports show their limitations to operate catalytic processes under severe reaction conditions. 展开更多
关键词 CO_(2)methanation Auto-methanation induction heating Depleted uranium oxide Electrification process Operando DRIFTS
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Indirect Vector Control of Linear Induction Motors Using Space Vector Pulse Width Modulation 被引量:1
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作者 Arjmand Khaliq Syed Abdul Rahman Kashif +5 位作者 Fahad Ahmad Muhammad Anwar Qaisar Shaheen Rizwan Akhtar Muhammad Arif Shah Abdelzahir Abdelmaboud 《Computers, Materials & Continua》 SCIE EI 2023年第3期6263-6287,共25页
Vector control schemes have recently been used to drive linear induction motors(LIM)in high-performance applications.This trend promotes the development of precise and efficient control schemes for individual motors.T... Vector control schemes have recently been used to drive linear induction motors(LIM)in high-performance applications.This trend promotes the development of precise and efficient control schemes for individual motors.This research aims to present a novel framework for speed and thrust force control of LIM using space vector pulse width modulation(SVPWM)inverters.The framework under consideration is developed in four stages.To begin,MATLAB Simulink was used to develop a detailed mathematical and electromechanical dynamicmodel.The research presents a modified SVPWM inverter control scheme.By tuning the proportional-integral(PI)controller with a transfer function,optimized values for the PI controller are derived.All the subsystems mentioned above are integrated to create a robust simulation of the LIM’s precise speed and thrust force control scheme.The reference speed values were chosen to evaluate the performance of the respective system,and the developed system’s response was verified using various data sets.For the low-speed range,a reference value of 10m/s is used,while a reference value of 100 m/s is used for the high-speed range.The speed output response indicates that themotor reached reference speed in amatter of seconds,as the delay time is between 8 and 10 s.The maximum amplitude of thrust achieved is less than 400N,demonstrating the controller’s capability to control a high-speed LIM with minimal thrust ripple.Due to the controlled speed range,the developed system is highly recommended for low-speed and high-speed and heavy-duty traction applications. 展开更多
关键词 Space vector pulse width modulation linear induction motor proportional-integral controller indirect vector control electromechanical dynamic modeling
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Harmonics in the Squirrel Cage Induction Motor,Analytic Calculation Part Ⅱ:Synchronous Parasitic Torques,Radial Magnetic Forces 被引量:1
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作者 G.Kovács 《CES Transactions on Electrical Machines and Systems》 CSCD 2023年第4期404-421,共18页
The magnetic field generated in the air gap of the cage asynchronous machine and the harmonics of the magnetomotive forces creating that magnetic field,as well as the synchronous parasitic torques,radial magnetic forc... The magnetic field generated in the air gap of the cage asynchronous machine and the harmonics of the magnetomotive forces creating that magnetic field,as well as the synchronous parasitic torques,radial magnetic forces have been discussed in great detail in the literature,but always separately,for a long time.However,systematization of the phenomenon still awaits.Therefore,it is worth summarizing the completeness of the phenomena in a single study–with a new approach at the same time-in order to reveal the relationships between them.The role of rotor slot number is emphasized much more than before.New formulas derived for both synchronous torques and radial magnetic forces are used for further investigation.It will be shown that both phenomena in subject must be treated together.Formulas will be provided to take into account attenuation.Design guide will be provided to avoid dangerous rotor slot numbers.It will be shown that the generation of synchronous torques and radial magnetic forces do not depend–in this new approach-on the slot combination,but on the rotor slot number itself. 展开更多
关键词 Squirrel cage induction motor Synchronous parasitic torques Radial magnetic forces Winding harmonics
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Harmonics in the Squirrel Cage Induction Motor Analytic Calculation-Part Ⅰ: Differential Leakage, Attenuation, Asynchronous Parasitic Torques 被引量:1
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作者 G.Kovács 《CES Transactions on Electrical Machines and Systems》 CSCD 2023年第3期320-329,共10页
The magnetic field generated in the air gap of the cage asynchronous machine and the harmonics of the magnetomotive forces creating that magnetic field, as well as the related differential leakage, attenuation, asynch... The magnetic field generated in the air gap of the cage asynchronous machine and the harmonics of the magnetomotive forces creating that magnetic field, as well as the related differential leakage, attenuation, asynchronous parasitic torques have been discussed in great detail in the literature, but always separately, for a long time. However, systematization of the phenomenon still awaits. Therefore, it is worth summarizing the completeness of the phenomena in a single study – with a new approach at the same time-in order to reveal the relationships between them. The role of rotor slot number is emphasized much more than before. An existing, commonly used, but still impractical basic figure has been modified to more clearly demonstrate the response of the rotor for the harmonics of the stator. The need to treat differential leakage, asynchronous parasitic torques and attenuation together will be demonstrated: new formula for asynchronous parasitic torque is derived;the long-used characteristic curves for differential leakage and attenuation used separately so far was merged into one, correct curve in order to provide a correct design guide for the engineers. 展开更多
关键词 Asynchronous parasitic torque ATTENUATION Differential leakage Squirrel cage induction motor Winding harmonics
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A chromosome-level genome assembly provides insights into Cornus wilsoniana evolution, oil biosynthesis, and floral bud development
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作者 Zhenxiang He Haoyu Chao +12 位作者 Xinkai Zhou Qingyang Ni Yueming Hu Ranran Yu Minghuai Wang Changzhu Li Jingzhen Chen Yunzhu Chen Yong Chen Chunyi Cui Liangbo Zhang Ming Chen Dijun Chen 《Horticulture Research》 SCIE CSCD 2023年第11期27-44,共18页
Cornus wilsoniana W.is a woody oil plant with high oil content and strong hypolipidemic effects,making it a valuable species for medicinal,landscaping,and ecological purposes in China.To advance genetic research on th... Cornus wilsoniana W.is a woody oil plant with high oil content and strong hypolipidemic effects,making it a valuable species for medicinal,landscaping,and ecological purposes in China.To advance genetic research on this species,we employed PacBio together with Hi-C data to create a draft genome assembly for C.wilsoniana.Based on an 11-chromosome anchored chromosome-level assembly,the estimated genome size was determined to be 843.51 Mb.The N50 contig size and N50 scaffold size were calculated to be 4.49 and 78.00 Mb,respectively.Furthermore,30474 protein-coding genes were annotated.Comparative genomics analysis revealed that C.wilsoniana diverged from its closest species∼12.46 million years ago(Mya).Furthermore,the divergence between Cornaceae and Nyssaceae occurred>62.22 Mya.We also found evidence of whole-genome duplication events and whole-genome triplicationγ,occurring at∼44.90 and 115.86 Mya.We further inferred the origins of chromosomes,which sheds light on the complex evolutionary history of the karyotype of C.wilsoniana.Through transcriptional and metabolic analysis,we identified two FAD2 homologous genes that may play a crucial role in controlling the oleic to linoleic acid ratio.We further investigated the correlation between metabolites and genes and identified 33 MADS-TF homologous genes that may affect f lower morphology in C.wilsoniana.Overall,this study lays the groundwork for future research aimed at identifying the genetic basis of crucial traits in C.wilsoniana. 展开更多
关键词 assembly EVOLUTION floral
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Control of epileptic activities in a cortex network of multiple coupled neural populations under electromagnetic induction
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作者 Zhongkui SUN Yuanyuan LIU +1 位作者 Xiaoli YANG Wei XU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第3期499-514,共16页
Epilepsy is believed to be associated with the abnormal synchronous neuronal activity in the brain,which results from large groups or circuits of neurons.In this paper,we choose to focus on the temporal lobe epilepsy,... Epilepsy is believed to be associated with the abnormal synchronous neuronal activity in the brain,which results from large groups or circuits of neurons.In this paper,we choose to focus on the temporal lobe epilepsy,and establish a cortex network of multiple coupled neural populations to explore the epileptic activities under electromagnetic induction.We demonstrate that the epileptic activities can be controlled and modulated by electromagnetic induction and coupling among regions.In certain regions,these two types of control are observed to show exactly reverse effects.The results show that the strong electromagnetic induction is conducive to eliminating the epileptic seizures.The coupling among regions has a conduction effect that the previous normal background activity of the region gives way to the epileptic discharge,owing to coupling with spike wave discharge regions.Overall,these results highlight the role of electromagnetic induction and coupling among the regions in controlling and modulating epileptic activities,and might provide novel insights into the treatments of epilepsy. 展开更多
关键词 EPILEPSY electromagnetic induction multiple coupled neural population dynamical transition
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龙葵UNUSUAL FLORAL ORGANS类SnUFO2基因C端序列的保守性对花发育的影响
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作者 周佳圆 钟玉 +2 位作者 努尔阿斯娅·伊马木 崔敏龙 朴春兰 《浙江农林大学学报》 CAS CSCD 北大核心 2023年第1期38-44,共7页
【目的】UNUSUAL FLORAL ORGANS(UFO)基因属于F-box基因家族,是重要的花器官特征基因。UFO基因N端能与Skp1类基因结合形成Skp1-Cullin1-F-box(SCF)复合体,参与泛素化过程并降解C端结合的靶蛋白。为了探究C端序列对龙葵Solanum nigrum花... 【目的】UNUSUAL FLORAL ORGANS(UFO)基因属于F-box基因家族,是重要的花器官特征基因。UFO基因N端能与Skp1类基因结合形成Skp1-Cullin1-F-box(SCF)复合体,参与泛素化过程并降解C端结合的靶蛋白。为了探究C端序列对龙葵Solanum nigrum花发育的影响,本研究克隆了一个C末端缺失的SnUFO2*基因并构建其表达载体转入龙葵植株中,观察转基因龙葵植株花器官变化,从而深入探讨UFO基因完整的C末端序列在龙葵花发育中的重要作用。【方法】利用生物信息学分析软件对SnUFO2*和全长的SnUFO2比较分析,采用实时荧光定量PCR(RT-qPCR)对SnUFO2*基因在野生型龙葵植株根、茎、叶、花苞中进行表达分析;通过超表达载体的构建、转基因植株表型的观察及石蜡切片技术验证SnUFO2基因的功能。【结果】SnUFO2*基因ORF长度为1302 bp,编码433个氨基酸,与龙葵中完整的SnUFO2基因相比,其C末端缺失了23个氨基酸。RT-qPCR结果显示:SnUFO2*基因在野生型植株的花苞中特异性表达。对转基因植株的表型观察发现:35S::SnUFO2*转基因龙葵植株的花瓣向萼片转化。石蜡切片分析发现:转基因龙葵植株雄蕊缺失,雌蕊处有不确定的分生组织产生。【结论】35S::SnUFO2*转基因龙葵植株花瓣、雄蕊和心皮发育异常。C端结构缺失可能降低了SnUFO2蛋白特异性识别靶蛋白的能力,说明该基因完整的C末端对龙葵花器官发育至关重要。 展开更多
关键词 转基因龙葵 SnUFO2 花分生组织 花器官发育 花发育
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