期刊文献+
共找到86,369篇文章
< 1 2 250 >
每页显示 20 50 100
A Comprehensive Review of Torque and Speed Control Strategies for Switched Reluctance Motor Drives 被引量:1
1
作者 Sreeram K Preetha P K +1 位作者 Javier Rodríguez-García Carlosálvarez-Bel 《CES Transactions on Electrical Machines and Systems》 2025年第1期46-75,共30页
Switched Reluctance Motors(SRMs),outfitted with rugged construction,good speed range,high torque density,and rare earth-free nature that outweigh induction motors(IM)and permanent magnet synchronous motor(PMSM),afford... Switched Reluctance Motors(SRMs),outfitted with rugged construction,good speed range,high torque density,and rare earth-free nature that outweigh induction motors(IM)and permanent magnet synchronous motor(PMSM),afford a broad range of applications in the domain of electric vehicles(EVs).Standard copper magnetic wire and low-carbon steel laminations are used to construct SRMs,which give them high efficiency in the range of 85-95%.Despite SRM's desirable features over traditional motor-speed drives,high torque ripples and radial distortions constrain their deployment in EVs.Precise rotor position is imperative for effective management of the speed and torque of SRMs.This paper provides an illustrative compendium on review of the torque-speed control and ripple mitigation techniques using design enhancements and control methods for SRM drives for EV applications.The various schemes were evaluated on their performance metricsoperational speed range,control complexity,practical realization,need for pre-stored parameters(look-up tables of current,inductance and torque profiles)and motor controller memory requirements.The findings provide valuable insights into balancing the gains and trade-offs associated with EV applications.Furthermore,they pinpoint opportunities for enhancement by analyzing the cost and technical aspects of different SRM controllers. 展开更多
关键词 Electric vehicles Switched reluctance motor Speed control torque control Traction motor torque ripple
在线阅读 下载PDF
功能矫治器对替牙期骨性AngleⅡ1错颌畸形患儿矫治效果的研究
2
作者 肖亦芳 杨珍 +1 位作者 廖健强 邓妹 《黑龙江医学》 2025年第15期1798-1801,共4页
目的:观察功能矫治器对骨性AngleⅡ1错颌畸形患儿的矫治效果。方法:选取2022年5—12月广西科技大学第一附属医院口腔门诊收治的18例骨性AngleⅡ1错颌畸形患儿作为研究对象,通过自身对照,使用功能矫治器矫治12个月,对比矫治前后拍摄的头... 目的:观察功能矫治器对骨性AngleⅡ1错颌畸形患儿的矫治效果。方法:选取2022年5—12月广西科技大学第一附属医院口腔门诊收治的18例骨性AngleⅡ1错颌畸形患儿作为研究对象,通过自身对照,使用功能矫治器矫治12个月,对比矫治前后拍摄的头影测量定位侧位片变化,并通过问卷调查分析满意度和患儿口腔“知信行”的变化情况。结果:治疗12个月后,患儿凸面型变为基本直面型,尖、磨牙基本中性关系,测量值SNB、ANB,Wits值、U1-SN、U1-NA、U1-NA距、OJ值减小,U1-L1、Z角、TLL-E距、SPP-SPPW、U-MPW和TB-TPPW增大,差异均有统计学意义(P<0.05),SNA、FH-MP、SN-MP增大、TUL-E线距减小、L1-MP角、L1-NB角、L1-NB距变化,差异均无统计学意义(P>0.05)。矫治满意度100%,可视菌斑检出率明显下降。结论:对骨性AngleⅡ1错颌畸形患儿使用功能矫治器矫治后,面型改善明显,口颌系统整体功能得到改善,青少年患儿及家长满意度高,在矫治过程中养成了较好的口腔卫生习惯。 展开更多
关键词 骨性angleⅡ1 功能矫治器 替牙期
暂未订购
Topographic factors associated with anterior chamber angle narrowing in patients with keratoconus 被引量:1
3
作者 Hamed Soltan-Dehghan Abdollah Farzaneh +2 位作者 Hassan Hashemi Payam Nabovati Mehdi Khabazkhoob 《International Journal of Ophthalmology(English edition)》 2025年第1期67-73,共7页
AIM:To identify topographic determinants of the anterior chamber angle(ACA)in patients with keratoconus(KCN).METHODS:Four hundred and ten eyes of 294 patients with KCN were recruited for this study.First,complete ocul... AIM:To identify topographic determinants of the anterior chamber angle(ACA)in patients with keratoconus(KCN).METHODS:Four hundred and ten eyes of 294 patients with KCN were recruited for this study.First,complete ocular examinations were performed for all patients,including visual acuity measurement,refraction,and slit-lamp biomicroscopy.Then,all participants underwent corneal imaging by the Oculus Pentacam HR.RESULTS:The mean age of the participants was 32.40±8.52y(15-60y)and 69.5%of them were male.The mean ACA was 38.47°±5.75°(range:14.40°to 56.50°)in the whole sample,38.24°±6.00°in males,and 38.98°±5.11°in females(P=0.447).The mean ACA was significantly different among different groups of cone morphology,as patients with nipple cones showed the lowest mean ACA.Moreover,there were statistically significant differences in the mean ACA among different groups of cone locations,with patients having central cones exhibiting the lowest mean ACA(P<0.001).Anterior and posterior Q values were significantly,directly correlated with ACA(anterior Q:r=0.122,P=0.014,posterior Q:r=0.192,P<0.001).CONCLUSION:This study provides critical insights into the risk factors for ACA narrowing in KCN patients,which is essential for planning intraocular surgeries.Patients with nipple and central cones exhibited the most significant ACA narrowing.Additionally,more negative Q-values are associated with increased ACA narrowing,highlighting the need for targeted diagnostic and therapeutic strategies. 展开更多
关键词 KERATOCONUS anterior chamber angle cone morphology cone location
原文传递
Determination of angle of attack and dynamic stall loop in the complex vortical flow of a vertical axis wind turbine 被引量:1
4
作者 Wenzhong Shen Tao Xie +2 位作者 Lingpeng Ge Jiamin Yin Zhenye Sun 《Theoretical & Applied Mechanics Letters》 2025年第1期9-16,共8页
To improve the vertical axis wind turbine(VAWT)design,the angle of attack(AOA)and airfoil data must be treated correctly.The present paper develops a method for determining AOA on a VAWT based on computational fluid d... To improve the vertical axis wind turbine(VAWT)design,the angle of attack(AOA)and airfoil data must be treated correctly.The present paper develops a method for determining AOA on a VAWT based on computational fluid dynamics(CFD)analysis.First,a CFD analysis of a two-bladed VAWT equipped with a NACA 0012 airfoil is conducted.The thrust and power coefficients are validated through experiments.Second,the blade force and velocity data at monitoring points are collected.The AOA at different azimuth angles is determined by removing the blade self-induction at the monitoring point.Then,the lift and drag coefficients as a function of AOA are extracted.Results show that this method is independent of the monitoring points selection located at certain distance to the blades and the extracted dynamic stall hysteresis is more precise than the one with the“usual”method without considering the self-induction from bound vortices. 展开更多
关键词 Vertical axis wind turbine Computational fluid dynamics angle of attack Dynamic stall
在线阅读 下载PDF
Unsteady aerodynamic modeling and analysis of aircraft model in multi-DOF coupling maneuvers at high angles of attack with attention mechanism 被引量:1
5
作者 Wenzhao DONG Xiaoguang WANG +1 位作者 Dongbo HAN Qi LIN 《Chinese Journal of Aeronautics》 2025年第6期349-361,共13页
Unsteady aerodynamic characteristics at high angles of attack are of great importance to the design and development of advanced fighter aircraft, which are characterized by post-stall maneuverability with multiple Deg... Unsteady aerodynamic characteristics at high angles of attack are of great importance to the design and development of advanced fighter aircraft, which are characterized by post-stall maneuverability with multiple Degrees-of-Freedom(multi-DOF) and complex flow field structure.In this paper, a special kind of cable-driven parallel mechanism is firstly utilized as a new suspension method to conduct unsteady dynamic wind tunnel tests at high angles of attack, thereby providing experimental aerodynamic data. These tests include a wide range of multi-DOF coupled oscillatory motions with various amplitudes and frequencies. Then, for aerodynamic modeling and analysis, a novel data-driven Feature-Level Attention Recurrent neural network(FLAR) is proposed. This model incorporates a specially designed feature-level attention module that focuses on the state variables affecting the aerodynamic coefficients, thereby enhancing the physical interpretability of the aerodynamic model. Subsequently, spin maneuver simulations, using a mathematical model as the baseline, are conducted to validate the effectiveness of the FLAR. Finally, the results on wind tunnel data reveal that the FLAR accurately predicts aerodynamic coefficients, and observations through the visualization of attention scores identify the key state variables that affect the aerodynamic coefficients. It is concluded that the proposed FLAR enhances the interpretability of the aerodynamic model while achieving good prediction accuracy and generalization capability for multi-DOF coupling motion at high angles of attack. 展开更多
关键词 Unsteady aerodynamics Aerodynamic modeling High angle of attack Wind tunnel test Attention mechanism
原文传递
Effects of bedding angles on rockburst proneness of layered anisotropic phyllites 被引量:1
6
作者 Lei Xu Fengqiang Gong +1 位作者 Jinhao Dai Zhichao He 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第7期4288-4313,共26页
To examine the effect of bedding angle upon burst proneness in terms of energy,phyllites with seven various bedding angles are selected for conventional uniaxial compression and single-cyclic loading eunloading uniaxi... To examine the effect of bedding angle upon burst proneness in terms of energy,phyllites with seven various bedding angles are selected for conventional uniaxial compression and single-cyclic loading eunloading uniaxial compression tests.The ejection and failure during compression process of phyllites are monitored in real-time by high-speed camera system.The results demonstrate that the phyllites with different bedding angles all consistently follow the linear energy storage and dissipation(LESD)law during compression.The ultimate energy storage of phyllites with varying bedding angles can be calculated precisely via using the LESD law.Based on this,four kinds of energy-based rockburst indices are applied to quantitatively assess the burst proneness for phyllites.Combined with the recorded images of high-speed camera system,ejection distance,and mass of rock fragments and powder,the burst proneness for phyllites with various bedding angles is qualitatively evaluated adopting the far-field ejection mass ratio.Next,burst proneness of anisotropic phyllites is assessed quantitatively and qualitatively.It is found that phyllites with bedding angles of 0°,15°,and 90°have a high burst proneness,and that with bedding angle of 30°has a medium burst proneness,whereas the ones with bedding angles of 45°,60°,and 75°have a low burst proneness.Finally,the published experimental data of shale and sandstone specimens with different bedding angles are extracted,and it is preliminarily verified that the bedding angle does not change the LESD law of rocks. 展开更多
关键词 Rock mechanics Bedding angle Rockburst proneness Linear energy storage and dissipation law Residual elastic energy
在线阅读 下载PDF
Physical Origin of Current-Induced Switching Angle Shift in Magnetic Heterostructures
7
作者 Xiaomiao Yin Guanglei Han +3 位作者 Guowen Gong Jun Kang Changmin Xiong Lijun Zhu 《Chinese Physics Letters》 2025年第11期238-243,共6页
Accurate quantification of the spin–orbit torques(SOTs) is critical for the identification and applications of new spin-orbitronic effects. One of the most popular techniques to quantify the SOTs is the “switching a... Accurate quantification of the spin–orbit torques(SOTs) is critical for the identification and applications of new spin-orbitronic effects. One of the most popular techniques to quantify the SOTs is the “switching angle shift”, where the applied direct current is assumed to shift, via domain wall depinning during anti-domain expansion, the switching angle of a perpendicular magnetization in a linear proportional manner under a large rotating magnetic field. Here, we report that, for the most commonly employed perpendicular magnetization heterostructures in spintronics(e.g., those based on FeCoB, Co, and Co/Ni multilayers), the switching angle shift considerably misestimates the SOT within the domain wall depinning analysis of the slope of linear-in-current scaling and may also have a non-zero residual value at zero direct current. Our experiments and simulations unveil that the switching angle shift is most likely dominated by chiral asymmetric nucleation rather than expansion of anti-domains. The in-plane field from external magnets and current-induced SOTs lowers the perpendicular nucleation field and thus reduces the required switching angle, ultimately leading to an underestimation of SOTs by domain wall depinning analysis. These results have advanced our understanding of magnetization switching in spintronic devices. 展开更多
关键词 switching angle shift spin orbit torques sots domain wall depinning large rotating magnetic field applied direct current magnetic heterostructures spin orbit torques perpendicular magnetization
原文传递
Study and application of the influence of inclination angle on the cross-fusion mechanism of high gas thick coal seam 被引量:1
8
作者 Pengxiang Zhao Zechen Chang +4 位作者 Shugang Li Risheng Zhuo Yongyong Jia Qiudong Shao Wen Lei 《International Journal of Mining Science and Technology》 2025年第1期69-85,共17页
In this study,to better decide the effect of coal seam dip angle upon the dynamic change of the crossfusion in gas transport and storage areas during the progress of working face in the high gas thick coal seam,a two-... In this study,to better decide the effect of coal seam dip angle upon the dynamic change of the crossfusion in gas transport and storage areas during the progress of working face in the high gas thick coal seam,a two-dimensional physical simulation experiment regarded as the theoretical research was conducted to properly explore the variation law of overburden fracture.The results demonstrated that the boundary of the gas transport zone was located in the region of fracture separation.The boundary of the gas storage area was located in the abrupt penetration zone.Also,according to the information theory,the state of the gas transport and storage areas was determined by the changing trend of the fracture rate and fracture entropy.The mathematical representation model of the dip effect in gas transport and storage areas was established.The criteria upon which the regional location of the gas transport area and gas storage area can be based were put forward.The cross-fusion evolution process of the dip effect in gas transport and storage areas was revealed as well.The research results could provide guidance for realising directional and accurate gas extraction. 展开更多
关键词 Coal seam dip angle Cross fusion High gas thick coal seam Overburden fracture Gas transport and storage areas
在线阅读 下载PDF
South American Breakup and Andean Torque Deformation
9
作者 Adolfo Antonio Gutiérrez 《Open Journal of Geology》 2025年第2期69-86,共18页
Geological deformations are generally attributed to compressional, extensional and strike-slip processes. Since the breakup of Gondwana, torque deformation has been responsible for the current configuration of the wes... Geological deformations are generally attributed to compressional, extensional and strike-slip processes. Since the breakup of Gondwana, torque deformation has been responsible for the current configuration of the western coasts of Africa and the eastern shore of South America and the morphotectonic geometry of the rift basins of South America, conditioning the morphostructure of the Andean chain and the current geoforms of the foreland. 展开更多
关键词 TECTONIC torque Deformation Continental Drift Rift Valley South America
在线阅读 下载PDF
Recent progress on electron-and magnon-mediated torques
10
作者 Jia-Min Lai Bingyue Bian +9 位作者 Zhonghai Yu Kaiwei Guo Yajing Zhang Pengnan Zhao Xiaoqian Zhang Chunyang Tang Jiasen Cao Zhiyong Quan Fei Wang Xiaohong Xu 《Chinese Physics B》 2025年第10期18-37,共20页
The growing demand for artificial intelligence and complex computing has underscored the urgent need for advanced data storage technologies.Spin-orbit torque(SOT)has emerged as a leading candidate for high-speed,high-... The growing demand for artificial intelligence and complex computing has underscored the urgent need for advanced data storage technologies.Spin-orbit torque(SOT)has emerged as a leading candidate for high-speed,high-density magnetic random-access memory due to its ultrafast switching speed and low power consumption.This review systematically explores the generation and switching mechanisms of electron-mediated torques(including both conventional SOTs and orbital torques)and magnon-mediated torques.We discuss key materials that enable these effects:heavy metals,topological insulators,low-crystal-symmetry materials,non-collinear antiferromagnets,and altermagnets for conventional SOTs;3d,4d,and 5d transition metals for orbital torques;and antiferromagnetic insulator Ni O-and multiferroic Bi Fe O_(3)-based sandwich structures for magnon torques.We emphasize that although key components of SOT devices have been demonstrated,numerous promising materials and critical questions regarding their underlying mechanisms remain to be explored.Therefore,this field represents a dynamic and rapidly evolving frontier in spintronics,offering significant potential for advancing next-generation information storage and computational technologies. 展开更多
关键词 spin-orbit torque orbital torque magnon torque altermagnet
原文传递
Enhanced Spin-Orbit Torque Induced by Interfacial Scattering in Ir/Pt Superlattice
11
作者 Jiahui Li Jing Dong +19 位作者 Yuqiang Wang Mingtong Zhu Yang Yao Ying Meng Jiyang Ou Guibin Lan Xuming Luo Jihao Xia Hongjun Xu Yizhan Wang Jiafeng Feng Hongxiang Wei Congli He Richeng Yu Junwei Zhang Yong Peng Nianpeng Lu Caihua Wan Xiufeng Han Guoqiang Yu 《Chinese Physics Letters》 2025年第5期140-150,共11页
The mechanisms of enhancing spin-orbit torque(SOT) have attracted significant attention, particularly regarding the influence of extrinsic scattering mechanisms on SOT efficiency, as they complement intrinsic contribu... The mechanisms of enhancing spin-orbit torque(SOT) have attracted significant attention, particularly regarding the influence of extrinsic scattering mechanisms on SOT efficiency, as they complement intrinsic contributions. In multilayer systems, extrinsic interfacial scattering, along with scattering from defects or impurities inside the materials, plays a crucial role in affecting the SOT efficiency. In this study, we successfully fabricated high-quality epitaxially grown [Ir/Pt]N superlattices with an increasing number of interfaces using a magnetron sputtering system to investigate the contribution of extrinsic interfacial scattering to SOT efficiency. We measured SOT efficiency through spin-torque ferromagnetic resonance methods and determined the spin Hall angle using the spin pumping technique. Additionally, we calculated spin transparency based on the SOT efficiency and spin Hall angle. Our findings indicate that the values of SOT efficiency, spin Hall angle, and spin transparency are enhanced in the superlattice structure compared to Pt, which we attribute to the increase in interfacial scattering.This research offers an effective strategy for designing and fabricating advanced spintronic devices. 展开更多
关键词 interfacial scattering spin transparency spin Hall angle extrinsic scattering mechanisms extrinsic interfacial scattering spin tronic devices ir pt superlattice spin orbit torque
原文传递
Analytical Method of Permanent Magnet Torque Machine with High Torque for Considering the Influence of Armature Magnetic Field
12
作者 Jiawei Chai Xianguo Gui +1 位作者 Qiang Gao Dianguo Xu 《CES Transactions on Electrical Machines and Systems》 2025年第3期289-299,共11页
Compared to the conventional permanent magnet synchronous machine(PMSM),the main characteristic of permanent magnet torque machine(PMTM)with high torque is that armature current is high,which has a great influence on ... Compared to the conventional permanent magnet synchronous machine(PMSM),the main characteristic of permanent magnet torque machine(PMTM)with high torque is that armature current is high,which has a great influence on magnetic circuit saturation,so this paper proposes a novel analytical method(AM)considering this problem.The key of this new AM is to consider armature reaction flux and armature leakage flux,which are closely related to output torque.Firstly,the expressions,including magnetomotive force(MMF)generated by permanent magnets(PMs)and armature windings are derived,and meanwhile slotting effect is considered by planning flux path.In addition,the expression of leakage flux density generated by armature windings are calculated,and flux density equivalence coefficient of tooth is calculated to be 2/3,which is used to solve the problem of uneven saturation of each tooth.Then,based on main flux factor and leakage flux factor proposed,an improved iteration process is proposed,and by this new process,the flux density of each yoke and tooth can be obtained,which is beneficial to obtain more accurate air-gap flux density and flux linkage.Finally,a prototype of 60-pole 54-slot is fabricated,and the performances of the electric machine,such as back electromotive force(EMF)and output torque,are calculated by this new AM and finite element method(FEM).The results of FEM and experimental test show that this new AM is good enough to calculate the performance of PMTM. 展开更多
关键词 Analytical method(AM) Permanent magnet torque machine(PMTM) High torque Leakage flux Equivalence coefficient
在线阅读 下载PDF
Relationship between angle kappa,angle alpha and objective visual quality in patients with multifocal intraocular lens
13
作者 Zhu Chaojie Long Tan +2 位作者 Ma Ting Yan Jie Wang Rui 《国际眼科杂志》 2025年第9期1399-1405,共7页
AIM:To investigate how angles kappa and alpha affect postoperative visual quality in patients with multifocal intraocular lens(mIOLs)implantation.METHODS:Retrospective cases series.A total of 46 patients(46 eyes)who u... AIM:To investigate how angles kappa and alpha affect postoperative visual quality in patients with multifocal intraocular lens(mIOLs)implantation.METHODS:Retrospective cases series.A total of 46 patients(46 eyes)who underwent phacoemulsification were subsumed.The correlation between Preoperative angles kappa and alpha,wave-front aberrations and objective visual quality of cornea,internal,and total eye after surgery were analyzed using iTrace.RESULTS:The magnitude of angle kappa was negatively correlated with internal and total modulation transfer function(MTF)at 3 mm;the magnitude of angle kappa was positively correlated with astigmatism,trefoil,higher-order aberrations(HOAs)of both internal and total eye at 3 mm.The magnitude of angle alpha was negatively correlated with total MTF and total Strehl ratio at 3 mm.The magnitude of angle alpha was positively correlated with corneal coma at 5 mm,internal astigmatism at both 3 mm and 5 mm,and total spherical aberration(SA)at 3 mm.Multivariate linear regression analysis showed that,among candidate independent variables(kappa,alpha,astigmatism,SA,coma,trefoil,and HOAs),astigmatism is the only independent factor for altering corneal MTF at 3 mm and 5 mm;astigmatism and HOAs emerged as independent factors for altering internal MTF at 3 mm and 5 mm,and total MTF at 3 mm;astigmatism,SA and HOAs emerged as independent factors for altering total MTF at 5 mm.CONCLUSION:With greater preoperative angle kappa or angle alpha,patients who accept mIOL implantation tend to have larger internal astigmatism and HOAs,which resulting in poor visual quality,especially those with small pupil size. 展开更多
关键词 angle kappa angle alpha modulation transfer function CATARACT Strehl ratio
暂未订购
Alpha and Kappa angle on postoperative visual quality in cataract surgery
14
作者 Xiao-Na Chen Ying-Yue Xiong +2 位作者 Jia Wei Bin Luo Ya-Li Gao 《International Journal of Ophthalmology(English edition)》 2025年第6期1023-1031,共9页
AIM:To explore the effect of Alpha angle and Kappa angle before multifocal intraocular lenses(MIOLs)implantation on postoperative visual quality of patients.METHODS:Before and 3mo after cataract surgery,Alpha angle an... AIM:To explore the effect of Alpha angle and Kappa angle before multifocal intraocular lenses(MIOLs)implantation on postoperative visual quality of patients.METHODS:Before and 3mo after cataract surgery,Alpha angle and Kappa angle were collected using IOL Master 700,iTrace,and Pentacam for clinical observation.Postoperative visual quality indicators,including high-order aberrations(HOA),modulation transfer function(MTF)and point spread function(PSF),were collected using iTrace.multiple linear regression analysis was used to analyze the correlation of the Kappa angle and the Alpha angle with age,axial length(AL),anterior chamber depth(ACD),keratometry(K),lens thickness(LT)and corneal white to white distance(WTW).Pearson correlation coefficient was used to analyze the correlation between Alpha angle and Kappa angle;Bland Altman analysis was used to evaluate the consistency of pairwise detection results of three instruments.RESULTS:The Alpha angle was modeled as Alpha=2.230+0.003×age-0.036×AL-0.025×K-0.058×WTW and the Kappa angle was modeled as Kappa=0.685+0.003×age-0.013×K-0.061×WTW.The correlation between the total Alpha angle and Kappa angle of the three instruments was weakly positive(r=0.291,P=0.000).Comparing the measurement of Alpha angle and Kappa angle using three instruments,only IOL Master 700 and iTrace showed good consistency in measuring Kappa angle(P=0.4254).After 3mo of surgery,the Alpha angle and Kappa angle significantly decreased(P=0.011,0.018;P=0.008,0.036).△Kappa=1.136-0.021×AL-0.013×K.Kappa angle could positively predict HOA(β=0.18,P=0.000),MTF(β=0.171,P=0.000),PSF(β=0.088,P=0.000),Alpha angle cannot(P>0.05).CONCLUSION:The patients with older age,flatter K and shorter WTW should be alert to the possibility of larger Alpha angle and Kappa angle.Alpha angle should also consider the factor of AL.When selecting patients with MIOLs implantation,there is no need to consider the Alpha angle.Careful consideration should be given to the Kappa angle,and the preoperative standard of<0.5 mm can refer to△Kappa=1.136-0.021×AL-0.013×K and be appropriately relaxed. 展开更多
关键词 kappa angle alpha angle postoperative visual quality cataract surgery ocular biometric instruments
原文传递
Angle closure glaucoma in a patient with X-linked retinoschisis:a case report
15
作者 Lu Yao Ye Lu +4 位作者 Kang-Yi Yang Kun Lyu Zong-Yi Wang Lyu-Zhen Huang Hui-Juan Wu 《International Journal of Ophthalmology(English edition)》 2025年第3期557-561,共5页
Dear Editor,X-linked retinoschisis(XLRS)is a rare X-linked recessive disorder predominantly afflicting young males.The schisis of the retinal layers is a result of deleterious mutations in the RS1 gene.Insufficient ep... Dear Editor,X-linked retinoschisis(XLRS)is a rare X-linked recessive disorder predominantly afflicting young males.The schisis of the retinal layers is a result of deleterious mutations in the RS1 gene.Insufficient epidemiological data has caused significant variation in reported global prevalence,with estimates fluctuating between 1 in 5000 and 1 in 30000 individuals[1].A large follow-up multicenter study recently published has yielded noteworthy findings concerning the phenotypic spectrum,long-term natural history,and genotype of XLRS.The investigation revealed a significant variability in visual function and disease progression,with particular variants of the RS1 gene displaying diverse phenotypic expressions,suggesting the intricate genetic basis underlying this disorder[2].The range of visual impairments associated with XLRS is extensive,varying from minor to severe.This condition is also characterized by specific retinal abnormalities,including radial streaks emanating from a divided central fovea,schisis affecting the inner layers of the retina in peripheral areas,and a diminished amplitude ratio of b-to a-wave,or even an electronegative electroretinography(ERG)[3].At their initial consultation,the majority of individuals with XLRS exhibit visual acuity(VA)levels between 20/60 and 20/120.However,there is a significant diversity in the condition’s presentation and progression,even among relatives,with VA levels spanning from near-normal to complete loss of sight[4-5].While vision tends to be reasonably consistent over several years for those with XLRS,there is documentation of a more rapid decline in later adulthood,specifically during the fourth and fifth decades,due to central retinal degeneration[5-7].Moreover,those with XLRS face an elevated risk for serious visual issues,such as retinal detachment,vitreous hemorrhages,and neovascular glaucoma[4].Female carriers could be found with slightly abnormal retinal changes without clinical symptoms[5].Even within the same family,the manifestation and progression of the condition can vary greatly,with individuals experiencing anything from nearly normal vision to complete loss of sight[8-9].Earlier investigations have revealed that retinoschisisrelated cystoid degeneration can impact multiple layers of the retina,beginning at the retinal nerve fiber zone and continuing to the nuclear stratum,with considerable fluctuation in the severity of the schisis[10-13]. 展开更多
关键词 DELETE CLOSURE angle
原文传递
Improvement of Torque and Loss Characteristics for an In-wheel Permanent Magnet Motor based on Dominant Airgap Harmonic
16
作者 Jiawei Ren Xiaoyong Zhu +1 位作者 Li Quan Zixuan Xiang 《CES Transactions on Electrical Machines and Systems》 2025年第3期313-319,共7页
In this paper,a 12/14-pole permanent magnet in-wheel motor is studied for potential in-wheel application,and the torque and loss are improved simultaneously based on designing and optimizing the corresponding dominant... In this paper,a 12/14-pole permanent magnet in-wheel motor is studied for potential in-wheel application,and the torque and loss are improved simultaneously based on designing and optimizing the corresponding dominant harmonics.The key of this study is to evaluate the contributions of harmonics on torque and loss,and further determines the harmonics related to them.Based on this,the torque enhancement factor and loss suppression factor are defined based on the selected dominant harmonics.And,the two factors are set as the optimization objectives,aiming at improving the characteristics of torque and loss.At the same time,to achieve an efficient optimization,a layered optimization method is presented,which includes magnet source layer and permeance layer.Based on the optimization,the motor torque is improved effectively,while the rotor iron loss is also reduced significantly.Then,a prototype motor is manufactured for experimental test.Finally,the simulation analysis and test results verify the validation of the studied motor and the proposed optimization method based on dominant harmonics. 展开更多
关键词 In-wheel motor Flux modulation Harmonic analysis torque Rotor loss
在线阅读 下载PDF
Real-time drilling torque prediction ahead of the bit with just-in-time learning
17
作者 Kan-Kan Bai Mao Sheng +2 位作者 Hong-Bao Zhang Hong-Hai Fan Shao-Wei Pan 《Petroleum Science》 2025年第1期430-441,共12页
The digital twin,as the decision center of the automated drilling system,incorporates physical or data-driven models to predict the system response(rate of penetration,down-hole circulating pressure,drilling torques,e... The digital twin,as the decision center of the automated drilling system,incorporates physical or data-driven models to predict the system response(rate of penetration,down-hole circulating pressure,drilling torques,etc.).Real-time drilling torque prediction aids in drilling parameter optimization,drill string stabilization,and comparing the discrepancy between observed signal and theoretical trend to detect down-hole anomalies.Due to their inability to handle huge amounts of time series data,current machine learning techniques are unsuitable for the online prediction of drilling torque.Therefore,a new way,the just-in-time learning(JITL)framework and local machine learning model,are proposed to solve the problem.The steps in this method are:(1)a specific metric is designed to measure the similarity between time series drilling data and scenarios to be predicted ahead of bit;(2)parts of drilling data are selected to train a local model for a specific prediction scenario separately;(3)the local machine learning model is used to predict drilling torque ahead of bit.Both the model data test results and the field data application results certify the advantages of the method over the traditional sliding window methods.Moreover,the proposed method has been proven to be effective in drilling parameter optimization and pipe sticking trend detection.Finally,we offer suggestions for the selection of local machine learning algorithms and real-time prediction with this approach based on the test results. 展开更多
关键词 Drilling torque prediction Just-in-time learning Digital twin Machine learning
原文传递
Interlayer exchange coupling effects on the spin-orbit torque in synthetic magnets
18
作者 Haodong Fan Zhongshu Feng +11 位作者 Tingwei Chen Xiaofeng Han Xinyu Shu Mingzhang Wei Shiqi Liu Mengxi Wang Shengru Chen Xuejian Tang Menghao Jin Yungui Ma Bo Liu Tiejun Zhou 《Chinese Physics B》 2025年第9期654-661,共8页
Interlayer exchange coupling(IEC)plays a critical role in spin-orbit torque(SOT)switching in synthetic magnets.This work establishes a fundamental correlation between IEC and SOT dynamics within Co/Pt-based synthetic ... Interlayer exchange coupling(IEC)plays a critical role in spin-orbit torque(SOT)switching in synthetic magnets.This work establishes a fundamental correlation between IEC and SOT dynamics within Co/Pt-based synthetic antiferromagnets and synthetic ferromagnets.The antiferromagnetic and ferromagnetic coupling states are precisely engineered through Ruderman-Kittel-Kasuya-Yosida(RKKY)interactions by modulating the Ir spacer thickness.Experimental results reveal that the critical switching current density exhibits a strong positive correlation with the IEC strength,regardless of the coupling type.A comprehensive theoretical framework based on the Landau-Lifshitz-Gilbert equation elucidates how IEC contributes to the effective energy barrier that must be overcome during SOT-induced magnetization switching.Significantly,the antiferromagnetically coupled samples demonstrate enhanced SOT efficiency,with the spin Hall angle being directly proportional to the antiferromagnetic exchange coupling field.These insights establish a coherent physical paradigm for understanding IEC-dependent SOT dynamics and provide strategic design principles for the development of energy-efficient next-generation spintronic devices. 展开更多
关键词 interlayer exchange coupling spin-orbit torque synthetic antiferromagnet
原文传递
Toroidal torques due to n=1 magnetic perturbations in ITER baseline scenario
19
作者 Jingwei LI Li LI +5 位作者 Yueqiang LIU Yunfeng LIANG Yanfei WANG Lu TIAN Zhongqing LIU Fangchuan ZHONG 《Plasma Science and Technology》 2025年第1期39-51,共13页
Toroidal torques,generated by the resonant magnetic perturbation(RMP)and acting on the plasma column,are numerically systematically investigated for an ITER baseline scenario.The neoclassical toroidal viscosity(NTV),i... Toroidal torques,generated by the resonant magnetic perturbation(RMP)and acting on the plasma column,are numerically systematically investigated for an ITER baseline scenario.The neoclassical toroidal viscosity(NTV),in particular the resonant portion,is found to provide the dominant contribution to the total toroidal torque under the slow plasma flow regime in ITER.While the electromagnetic torque always opposes the plasma flow,the toroidal torque associated with the Reynolds stress enhances the plasma flow independent of the flow direction.A peculiar double-peak structure for the net NTV torque is robustly computed for ITER,as the toroidal rotation frequency is scanned near the zero value.This structure is found to be ultimately due to a non-monotonic behavior of the wave-particle resonance integral(over the particle pitch angle)in the superbanana plateau NTV regime in ITER.These findings are qualitatively insensitive to variations of a range of factors including the wall resistivity,the plasma pedestal flow and the assumed frequency of the rotating RMP field. 展开更多
关键词 toroidal torques resonant magnetic perturbation fieds plasma flow ITER baseline scenario
在线阅读 下载PDF
Initialization-Free Programmable Spin-Logic Gate in a Single Spin-Orbit Torque Device
20
作者 Jie Lin Shuai Zhang +13 位作者 Shihao Li Yan Xu Xin Li Wei Duan Jincheng Hou Chenxi Zhou Wei Zhan Zhe Guo Min Song Xiaofei Yang Yufeng Tian Xuecheng Zou Dan Feng Long You 《Engineering》 2025年第8期215-220,共6页
In-memory computing(IMC)based on spin-logic devices is regarded as an advantageous way to optimize the Von Neumann bottleneck.However,performing complete Boolean logic with spintronic devices typi-cally requires an in... In-memory computing(IMC)based on spin-logic devices is regarded as an advantageous way to optimize the Von Neumann bottleneck.However,performing complete Boolean logic with spintronic devices typi-cally requires an initialization operation,which can reduce processing speed.In this work,we conceptu-alize and experimentally demonstrate a programmable and initialization-free spin-logic gate,leveraging spin-orbit torque(SOT)to effectuate magnetization switching,assisted by in-plane Oersted field gener-ated by an integrated bias-field Au line.This spin-logic gate,fabricated as a Hall bar,allows complete Boolean logic operations without initialization.A current flowing through the bias-field line,which is electrically isolated from the device by a dielectric,generates an in-plane magnetic field that can invert the SOT-induced switching chirality,enabling on-the-fly complete Boolean logic operations.Additionally,the device demonstrated good reliability,repeatability,and reproducibility during logic operations.Our work demonstrates programmable and scalable spin-logic functions in a single device,offering a new approach for spin-logic operations in an IMC architecture. 展开更多
关键词 Spin logic Complete Boolean logic Spin-orbit torque Fully electrical operations Initialization-free
在线阅读 下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部