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Analytical computation of magnetic field in coil-dominated superconducting quadrupole magnets based on racetrack coils
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作者 Chuang Shen Ying-Shun Zhu Fu-San Chen 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第4期119-135,共17页
Currently,three types of superconducting quadrupole magnets are used in particle accelerators:cos 2θ,CCT,and serpentine.However,all three coil configurations have complex spatial geometries,which make magnet manufact... Currently,three types of superconducting quadrupole magnets are used in particle accelerators:cos 2θ,CCT,and serpentine.However,all three coil configurations have complex spatial geometries,which make magnet manufacturing and strain-sensitive superconductor applications difficult.Compared with the three existing quadrupole coils,the racetrack quadrupole coil has a simple shape and manufacturing process,but there have been few theoretical studies.In this paper,the two-dimensional and three-dimensional analytical expressions for the magnetic field in coil-dominated racetrack superconducting quadrupole magnets are presented.The analytical expressions of the field harmonics and gradient are fully resolved and depend only on the geometric parameters of the coil and current density.Then,a genetic algorithm is applied to obtain a solution for the coil geometry parameters with field harmonics on the order of 10^(-4).Finally,considering the practical engineering needs of the accelerator interaction region,electromagnetic design examples of racetrack quadrupole magnets with high gradients,large apertures,and small apertures are described,and the application prospects of racetrack quadrupole coils are analyzed. 展开更多
关键词 Superconducting quadrupole magnet Racetrack coil Multipole field Genetic algorithm Magnetic design
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Gradient coil design with enhanced shielding constraint for a cryogen-free superconducting MRI system
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作者 Yaohui Wang Weimin Wang +3 位作者 Hui Liu Shunzhong Chen Feng Liu Qiuliang Wang 《Magnetic Resonance Letters》 2024年第1期1-9,共9页
The relatively fragile low-temperature stability of cryogen-free superconducting magnetic resonance imaging(MRI)magnets requires the careful management of exogenous heat sources.A strongly shielded gradient magnetic f... The relatively fragile low-temperature stability of cryogen-free superconducting magnetic resonance imaging(MRI)magnets requires the careful management of exogenous heat sources.A strongly shielded gradient magnetic field is important for the optimal operation of cryogen-free MRI systems.In this study,we present an enhanced shielding method incorporating a regionalized stray field constraining strategy.By optimizing the constraint parameters,we could develop engineering-feasible gradient coil schemes without increasing system complexity but with the stray field intensity reduced by half.In real measurement in an integrated MRI system,the developed gradient assembly demonstrated good performance and supported to output images of excellent quality.Our findings suggested that the proposed method could potentially form a useful design paradigm for cryogen-free MRI magnets. 展开更多
关键词 MRI Gradient coil Superconducting magnet Cryogen-free Magnetic shielding
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Effect of coil and chamber structure on plasma radial uniformity in radio frequency inductively coupled plasma
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作者 赵洋 周晓华 +2 位作者 高升荣 宋莎莎 赵玉真 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第7期58-66,共9页
Enhancing plasma uniformity can be achieved by modifying coil and chamber structures in radio frequency inductively coupled plasma(ICP)to meet the demand for large-area and uniformly distributed plasma in industrial m... Enhancing plasma uniformity can be achieved by modifying coil and chamber structures in radio frequency inductively coupled plasma(ICP)to meet the demand for large-area and uniformly distributed plasma in industrial manufacturing.This study utilized a two-dimensional self-consistent fluid model to investigate how different coil configurations and chamber aspect ratios affect the radial uniformity of plasma in radio frequency ICP.The findings indicate that optimizing the radial spacing of the coil enhances plasma uniformity but with a reduction in electron density.Furthermore,optimizing the coil within the ICP reactor,using the interior point method in the Interior Point Optimizer significantly enhances plasma uniformity,elevating it from 56%to 96%within the range of the model sizes.Additionally,when the chamber aspect ratio k changes from 2.8 to 4.7,the plasma distribution changes from a center-high to a saddleshaped distribution.Moreover,the plasma uniformity becomes worse.Finally,adjusting process parameters,such as increasing source power and gas pressure,can enhance plasma uniformity.These findings contribute to optimizing the etching process by improving plasma radial uniformity. 展开更多
关键词 inductively coupled plasma fluid simulation optimized coil chamber aspect ratio plasma uniformity
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Fuzzy Proportional Integral Derivative control of a voice coil actuator system for adaptive deformable mirrors
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作者 Ziqiang Cui Heng Zuo +4 位作者 Weikang Qiao Hao Li Fujia Du Yifan Wang Jinrui Guo 《Astronomical Techniques and Instruments》 CSCD 2024年第3期179-186,共8页
Research on adaptive deformable mirror technology for voice coil actuators(VCAs)is an important trend in the development of large ground-based telescopes.A voice coil adaptive deformable mirror contains a large number... Research on adaptive deformable mirror technology for voice coil actuators(VCAs)is an important trend in the development of large ground-based telescopes.A voice coil adaptive deformable mirror contains a large number of actuators,and there are problems with structural coupling and large temperature increases in their internal coils.Additionally,parameters of the traditional proportional integral derivative(PID)control cannot be adjusted in real-time to adapt to system changes.These problems can be addressed by introducing fuzzy control methods.A table lookup method is adopted to replace real-time calculations of the regular fuzzy controller during the control process,and a prototype platform has been established to verify the effectiveness and robustness of this process.Experimental tests compare the control performance of traditional and fuzzy proportional integral derivative(Fuzzy-PID)controllers,showing that,in system step response tests,the fuzzy control system reduces rise time by 20.25%,decreases overshoot by 78.24%,and shortens settling time by 67.59%.In disturbance rejection experiments,fuzzy control achieves a 46.09%reduction in the maximum deviation,indicating stronger robustness.The Fuzzy-PID controller,based on table lookup,outperforms the standard controller significantly,showing excellent potential for enhancing the dynamic performance and disturbance rejection capability of the voice coil motor actuator system. 展开更多
关键词 Adaptive optics Deformable mirror Voice coil actuator Fuzzy control
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Mathematical Modelling and Design of Helical Coil Heat Exchanger for Production of Hot Air for Fluidized Bed Dryer
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作者 Iniubong James Uwa Uwem Ekwere Inyang Innocent Oseribho Oboh 《Advances in Chemical Engineering and Science》 CAS 2024年第3期125-136,共12页
In global industrialization, efforts have been made to increase the rate of heat transfer in heat exchanger, minimizing the size of heat exchanger to reduce cost as well as increasing the effectiveness. Helical coil h... In global industrialization, efforts have been made to increase the rate of heat transfer in heat exchanger, minimizing the size of heat exchanger to reduce cost as well as increasing the effectiveness. Helical coil heat exchanger (HCHE) has been proven to be effective in improving heat transfer due to its large surface area. In this study, HCHE was designed to provide hot air needed for fluidized bed drying processes. The HCHE design model was fabricated and evaluated to study the efficiency of the hot air output for a laboratory fluidized bed dryer. The mathematical model for estimation of the final (output) temperature of air, Taf, passing through the HCHE was developed and validated experimentally. The drying of bitter kola particulates was carried out with a drying temperature of 50C 3C and a bed height-to-bed diameter ratio (H/D) of 1.5. The time taken to dry bitter kola particulates to 0.4% moisture content was 1 hour 45 minutes. Hence, HCHE is recommended for use in the production of hot for laboratory-scale fluidized bed dryers. 展开更多
关键词 Helical coil Heat Exchanger Fluidized Bed Dryer Heat Transfer Output Air Temperature
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Transient multi-physics behavior of an insert high temperature superconducting no-insulation coil in hybrid superconducting magnets with inductive coupling 被引量:1
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作者 Xiang KANG Yujin TONG +1 位作者 Wei WU Xingzhe WANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第2期255-272,共18页
A transient multi-physics model incorporated with an electromagneto-thermomechanical coupling is developed to capture the multi-field behavior of a single-pancake(SP)insert no-insulation(NI)coil in a hybrid magnet dur... A transient multi-physics model incorporated with an electromagneto-thermomechanical coupling is developed to capture the multi-field behavior of a single-pancake(SP)insert no-insulation(NI)coil in a hybrid magnet during the charging and discharging processes.The coupled problem is resolved by means of the finite element method(FEM)for the magneto-thermo-elastic behaviors and the Runge-Kutta method for the transient responses of the electrical circuits of the hybrid superconducting magnet system.The results reveal that the transient multi-physics responses of the insert NI coil primarily depend on the charging/discharging procedure of the hybrid magnet.Moreover,a reverse azimuthal current and a compressive hoop stress are induced in the insert NI coil during the charging process,while a forward azimuthal current and a tensile hoop stress are observed during the discharging process.The induced voltages in the insert NI coil can drive the currents flowing across the radial turns where the contact resistance exists.Therefore,it brings forth significant Joule heat,causing a temperature rise and a uniform distribution of this heat in the coil turns.Accordingly,a thermally/mechanically unstable or quenching event may be encountered when a high operating current is flowing in the insert NI coil.It is numerically predicted that a quick charging will induce a compressive hoop stress which may bring a risk of buckling instability in the coil,while a discharging will not.The simulations provide an insight of hybrid superconducting magnets under transient start-up or shutdown phases which are inevitably encountered in practical applications. 展开更多
关键词 hybrid superconducting magnet high temperature superconducting(HTS)no-insulation(NI)coil inductive coupling multi-physics field thermal stability
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Degree of style coiling is associated with corolla-tube length in the nectarless flowers of Roscoea schneideriana
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作者 Bo Wang Ze-Yu Tong +3 位作者 Ying-Ze Xiong Xiao-Fan Wang W.Scott Armbruster Shuang-Quan Huang 《Plant Diversity》 SCIE CAS CSCD 2023年第6期748-751,共4页
The plant-pollinator‘arms race’model posits that a major driver of the evolution of elongated corollas in flowers is reciprocal selection for‘morphological fit’between pollinator-tongue length and access distance ... The plant-pollinator‘arms race’model posits that a major driver of the evolution of elongated corollas in flowers is reciprocal selection for‘morphological fit’between pollinator-tongue length and access distance to nectar(usually corolla-tube length).Evidence for the pollinator-mediated selection on tube length and evolution of multiple,correlated floral traits remains inconclusive.To gain possible insights into the strength of stabilizing selection by assessing standing phenotypic variation,we measured a series of functionally important floral traits,including corolla tube length and‘effective’tube depth and degree of style coiling.We then calculated coefficients of variation(CV)for these traits in three field populations of R.schneideriana.Unlike in most long-tubed flowers,the bottom part of the corolla tube is completely occupied by the style,with no room for nectar.The length of this portion of the corolla tube was more variable(higher CV)than the upper part of the corolla tube,suggesting that functional tube depth was under stronger stabilizing selection.The degree of style coiling was negatively related to the corolla-tube length in all three populations of R.schneideriana,suggesting that there may be conflicting selection acting on style length and corolla-tube length,which are otherwise usually tightly correlated.Given the lack of nectar in the flowers of this species,the long corolla tubes and long styles may represent morphological holdovers from ancestors that were pollinated by long-tongued pollinators,as is still seen in related species in the western Himalayas. 展开更多
关键词 Coefficient of variation coiled style Corolla-tube length Nectar depth Pollinator shift Trait covariation
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Mechanical compression management of the right middle cerebral artery inferior trunk using a stent during coil embolization of middle cerebral artery aneurysms:A case report and literature review
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作者 Zhengyu Wang Zhiqing Peng +2 位作者 Liang Chen Wanbin Li Yongli Wang 《Journal of Interventional Medicine》 2023年第3期126-129,共4页
Endovascular coil embolization is a minimally invasive,rapid,and effective method for the treatment of intracranial aneurysms.However,complications associated with coil embolization,such as intraoperative aneurysm rup... Endovascular coil embolization is a minimally invasive,rapid,and effective method for the treatment of intracranial aneurysms.However,complications associated with coil embolization,such as intraoperative aneurysm rupture or arterial occlusion,should be promptly managed during the procedure to avoid catastrophic consequences.This study presents a case of mechanical compression management of the right middle cerebral artery(MCA)inferior trunk during coil embolization for bilateral MCA aneurysms.The inferior trunk of the right MCA was abruptly occluded due to mechanical compression during coil embolization of the right MCA bifurcation aneurysm.A Solitaire AB stent(4×20 mm,Covidien/Medtronic,Dublin,Ireland)was implanted in the inferior trunk of the right MCA after tirofiban was injected via a microcatheter,and the right inferior trunk was recanalized.The patient also underwent coil embolization of the left MCA bifurcation aneurysm,without any complications.It is crucial to recognize compressive occlusion of adjacent aneurysm branches to avoid severe complications during intracranial aneurysm embolization.Stent placement is a rescue treatment option for recanalization of an occluded artery. 展开更多
关键词 Endovascular coil embolization Intracranial aneurysm Mechanical compression STENT
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Fatigue Life Analysis of Coiled Tubing in Deep Well Jet Plugging Removal
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作者 Ju Liu Qiao Wang +3 位作者 Wei Zhang Zhihong Zhou Wenzhong Hu Yan Wang 《World Journal of Engineering and Technology》 2023年第1期48-54,共7页
The coiled tubing plugging has become the main means of plugging in gas Wells in Xinjiang. These Wells are deep and have high pressure, which can easily affect the fatigue life of the operating coiled tubing. In order... The coiled tubing plugging has become the main means of plugging in gas Wells in Xinjiang. These Wells are deep and have high pressure, which can easily affect the fatigue life of the operating coiled tubing. In order to improve the life of coiled tubing in high-pressure gas Wells, this paper studies the plugging conditions of coiled tubing in high-pressure ultra-deep Wells. Firstly, the cross section deformation of coiled tubing under high internal pressure is analyzed. Secondly, the factors influencing the fatigue life of coiled tubing and the influence of surface damage on the fatigue life of coiled tubing were studied. Finally, the mechanism of furrow damage caused by coiled tubing and the main measures to reduce furrow damage are analyzed. The following suggestions are made to improve the life of coiled tubing: select the right material and the right size coiled tubing;Use appropriate measures to prevent premature coiled tubing failure and reduce operating costs. 展开更多
关键词 coiled Tubing Plug Removal by Jetting Fatigue Life Plough Surface Damage RESONANCE
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Stent-assisted coiling of intracranial carotid ophthalmic segment aneurysm segment aneurysms:Long-term follow-up from a single center
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作者 Wenquan Gu Geng Zhou +10 位作者 Aizada Aldiyarova Tengyue Liu Yi Zhang Weidong Liu Lingping Meng Binxian Gu MingHua Li Ming Su Chen Su Aihua Liu Wu Wang 《Journal of Interventional Medicine》 2023年第3期116-120,共5页
Background:To evaluate the efficacy of stent-assisted coiling(SAC)for the treatment of carotid ophthalmic segment aneurysm segment aneurysms(OSAs)of the internal carotid artery(ICA)through detailed long-term follow-up... Background:To evaluate the efficacy of stent-assisted coiling(SAC)for the treatment of carotid ophthalmic segment aneurysm segment aneurysms(OSAs)of the internal carotid artery(ICA)through detailed long-term follow-up of a large patient cohort.Methods:We retrospectively analyzed 88 consecutive patients with OSAs between January 2009 and January 2020 at our center.Angiographic results were evaluated using the modified Raymond grading system and clinical outcomes were evaluated using the mRS scale.The primary endpoints were major aneurysm recurrence and poor clinical outcomes for at least 18 months of follow-up.The patients were asked to attend clinical follow-up assessments and possibly undergo DSA or MR via telephone.Results:We enrolled 88 patients with 99 OSAs treated with coiling,of whom 76 were treated with SAC.The coiling procedures were successful in all 88 patients.Overall,complications occurred in 8 patients(9.1%).No procedure-related mortality was observed.67(76.1%)experienced immediate aneurysm occlusion at the end of the procedure.Long-term angiographic follow-up(18 months)was available in 45/88 aneurysms(51%)(average 18.7±5.2 months).Four patients continued their follow-up for 5 years after initial aneurysm treatment.After a clinical follow-up time of 28.7 months(range,12-51 months),85 patients(95.5%)achieved favorable clinical outcomes(mRS scores of 0-2).Conclusions:This study indicates that SAC treatment is a safe and effective therapeutic alternative for ruptured and unruptured OSAs.The procedural risks are low with relatively long-term effectiveness. 展开更多
关键词 Endovascular treatment Stent-assisted coiling C6 segment aneurysm Occlusion rate Long-term follow-up
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Accurate surface normal representation to facilitate gradient coil optimization on curved surface
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作者 Hao Ren Hui Pan +2 位作者 Feng Jia Jan G.Korvink Zhenyu Liu 《Magnetic Resonance Letters》 2023年第1期67-84,I0004,共19页
The design methods for gradient coils are mostly based on discrete extrinsic methods(e.g.,the BioteSavart integration calculation),for which the surface normal vector strongly influences any numerical calculation of t... The design methods for gradient coils are mostly based on discrete extrinsic methods(e.g.,the BioteSavart integration calculation),for which the surface normal vector strongly influences any numerical calculation of the discretized surface.Previous studies are mostly based on regular or analytical surfaces,which allow normal vectors to be expressed analytically.For certain applications,design methods for extending currentcarrying surfaces from developable or analytic geometries to arbitrary surfaces generated from a scanned point cloud are required.The key task is to correctly express the discretized normal vectors to ensure geometrical accuracy of the designed coils.Mathematically,it has been proven that applying a Delaunay triangulation to approximate a smooth surface can result in the discrete elemental normal vectors converging to those of the original surface.Accordingly,this article uses Delaunay triangulation to expand upon previous design methods so that they encompass arbitrary piecewise continuous surfaces.Two design methods,the stream function and the so-called solid isotropic material with penalization(SIMP)method,are used to design circumvolute and noncircumvolute gradient coils on general surfaces. 展开更多
关键词 Gradient coils Delaunay triangulation Stream function SIMP method
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Design of Online Vision Detection System for Stator Winding Coil
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作者 李艳 李芮 徐洋 《Journal of Donghua University(English Edition)》 CAS 2023年第6期639-648,共10页
The quality of the stator winding coil directly affects the performance of the motor.A dual-camera online machine vision detection method to detect whether the coil leads and winding regions were qualified was designe... The quality of the stator winding coil directly affects the performance of the motor.A dual-camera online machine vision detection method to detect whether the coil leads and winding regions were qualified was designed.A vision detection platform was designed to capture individual winding images,and an image processing algorithm was used for image pre-processing,template matching and positioning of the coil lead area to set up a coordinate system.After eliminating image noise by Blob analysis,the improved Canny algorithm was used to detect the location of the coil lead paint stripped region,and the time was reduced by about half compared to the Canny algorithm.The coil winding region was trained with the ShuffleNet V2-YOLOv5s model for the dataset,and the detect file was converted to the Open Neural Network Exchange(ONNX)model for the detection of winding cross features with an average accuracy of 99.0%.The software interface of the detection system was designed to perform qualified discrimination tests on the workpieces,and the detection data were recorded and statistically analyzed.The results showed that the stator winding coil qualified discrimination accuracy reached 96.2%,and the average detection time of a single workpiece was about 300 ms,while YOLOv5s took less than 30 ms. 展开更多
关键词 machine vision online detection V2-YOLOv5s model Canny algorithm stator winding coil
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Design of new resonant magnetic perturbation coils on the J-TEXT tokamak
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作者 黄卓 周松 +11 位作者 樊金荣 李达 饶波 王能超 丁永华 毛飞越 黄名响 田微 陈忠勇 陈志鹏 梁云峰 the J-TEXT Team 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第11期142-149,共8页
The resonant magnetic perturbation(RMP)system is a powerful auxiliary system on tokamaks.On the J-TEXT tokamak,a set of new in-vessel coils is designed to enhance the amplitude of the RMP.The new coils are designed to... The resonant magnetic perturbation(RMP)system is a powerful auxiliary system on tokamaks.On the J-TEXT tokamak,a set of new in-vessel coils is designed to enhance the amplitude of the RMP.The new coils are designed to be two-turn saddle coils.These two-turn saddle coils have been optimized in terms of their structure,support,and protection components to overcome the limitations of the narrow in-vessel space,resulting in a compact coil module that can be accommodated in the vessel.To verify the feasibility of this design,an electromagnetic simulation is performed to investigate the electrical parameters and the generated field of the coils.A multi-field coupled simulation is performed to investigate the capacity of heat dissipation.As a result of these efforts,the new RMP coils have been successfully installed on the J-TEXT tokamak.It has significantly enhanced the RMP amplitude and been widely applied in experiments. 展开更多
关键词 fusion engineering TOKAMAK resonant magnetic perturbation coil multi-field coupled simulation(Some fioures may appeari in colour only in the online iournal)
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基于凸型线圈双向电磁力加载的管件电磁翻边成形 被引量:1
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作者 邱立 罗宝妮 +2 位作者 何琴 刘洪池 李智 《热加工工艺》 北大核心 2024年第9期152-158,共7页
传统线圈电磁力单一导致管件翻边角度不佳。本文提出采用凸型线圈管件翻边的方法,通过设计新型线圈,同时为管件翻边提供双向电磁力。建立了两组模型,分别采用传统线圈和凸型线圈驱动管件发生电磁翻边成形,探讨分析了两组管件模型翻边成... 传统线圈电磁力单一导致管件翻边角度不佳。本文提出采用凸型线圈管件翻边的方法,通过设计新型线圈,同时为管件翻边提供双向电磁力。建立了两组模型,分别采用传统线圈和凸型线圈驱动管件发生电磁翻边成形,探讨分析了两组管件模型翻边成形过程中的电磁力矢量以及变形速率的变化。结果表明,凸型线圈加载管件翻边时提供的双向电磁力极大地提高了管件变形的流动性,从而提高了翻边角度。此外,相同放电参数下基于凸型线圈的管件翻边角度较传统线圈提高了1.25倍。显然,新型线圈能够在一定程度上改善管件电磁翻边的质量问题,为电磁翻边成形的工业化应用提供更多可能。 展开更多
关键词 管件 电磁翻边 凸型线圈 双向电磁力 翻边角度
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磁聚焦式扭矩传感器激励线圈控制策略研究
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作者 王宪彬 孙士铭 +2 位作者 李志鹏 董晟 乔明泽 《仪表技术与传感器》 CSCD 北大核心 2024年第5期19-25,共7页
为测量旋转轴不同工况下的扭矩,提出了一种基于磁聚焦式扭矩传感器的激励线圈控制策略。该控制策略以控制传感器稳定输出幅值为2 mV电信号为目标,将感应电压数学模型和正交试验法相结合,对各个工况下的激励线圈控制策略进行设计,并利用M... 为测量旋转轴不同工况下的扭矩,提出了一种基于磁聚焦式扭矩传感器的激励线圈控制策略。该控制策略以控制传感器稳定输出幅值为2 mV电信号为目标,将感应电压数学模型和正交试验法相结合,对各个工况下的激励线圈控制策略进行设计,并利用MATLAB和COMSOL软件对各控制策略进行理论计算和有限元仿真验证。为模拟传感器在台架实验中得到的带噪声信号,对仿真得到的输出电信号添加高斯白噪声,利用MATLAB仿真软件对带噪声信号进行滤波优化。仿真结果表明:该控制策略能够使传感器在旋转轴的不同工况下,稳定输出幅值为2 mV的类正弦电压信号,验证了其可行性。 展开更多
关键词 磁聚焦 扭矩传感器 激励线圈控制策略 圆环线圈 滤波优化
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超早期介入栓塞破裂颅内动脉瘤治疗体会
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作者 徐亮 王根 +2 位作者 汤德刚 王维东 马骏 《临床神经外科杂志》 2024年第1期82-85,共4页
目的 研究在破裂出血急性期的颅内动脉瘤患者中,超早期(24 h内)采取介入栓塞治疗的临床疗效。方法 回顾性分析安徽医科大学附属滁州医院(滁州市第一人民医院)神经外科2020年4月—2022年7月收治的51例急诊破裂颅内动脉瘤患者,所有患者均... 目的 研究在破裂出血急性期的颅内动脉瘤患者中,超早期(24 h内)采取介入栓塞治疗的临床疗效。方法 回顾性分析安徽医科大学附属滁州医院(滁州市第一人民医院)神经外科2020年4月—2022年7月收治的51例急诊破裂颅内动脉瘤患者,所有患者均在24 h内采取介入栓塞治疗,对患者临床资料、治疗效果、术后并发症等情况进行总结。结合Raymond分级标准,对术中及术后栓塞情况进行分析,以格拉斯哥预后评分(GOS)为基础,对患者预后情况进行评估。结果 所有患者介入栓塞手术均成功完成,其中RaymondⅠ级栓塞35例,Ⅱ级及Ⅲ级栓塞分别有10例、6例,其中动脉瘤术中破裂3例,予以快速填塞弹簧圈等急救措施后完全栓塞;4例患者发生血栓事件,给予替罗非班溶栓等措施后血流恢复。患者预后情况用GOS评分进行评估,其中良好、轻度残疾、重度残疾、死亡患者数量分别为36例、8例、4例、3例,死亡率为5.88%,总体预后良好。结论 急诊超早期对破裂的颅内动脉瘤患者采取栓塞方法治疗,可以减少动脉瘤二次破裂出血的机会,提高患者生存率及生存质量。 展开更多
关键词 颅内动脉瘤 弹簧圈栓塞 手术时机 并发症
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NBCA医用胶联合弹簧圈三明治法栓塞脾动脉瘤17例疗效分析
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作者 焦周阳 马志岭 +6 位作者 连冲 张林枫 孙全敬 曹辉 徐鹏 化召辉 李震 《郑州大学学报(医学版)》 CAS 北大核心 2024年第5期693-697,共5页
目的:探讨氰基丙烯酸异丁酯(NBCA)医用胶联合弹簧圈三明治法栓塞脾动脉瘤的疗效及安全性。方法:选择2018年3月至2023年7月采用经导管注入NBCA医用胶和弹簧圈三明治法栓塞脾动脉瘤的患者17例,回顾性分析临床资料和影像资料,评价栓塞成功... 目的:探讨氰基丙烯酸异丁酯(NBCA)医用胶联合弹簧圈三明治法栓塞脾动脉瘤的疗效及安全性。方法:选择2018年3月至2023年7月采用经导管注入NBCA医用胶和弹簧圈三明治法栓塞脾动脉瘤的患者17例,回顾性分析临床资料和影像资料,评价栓塞成功率、临床疗效及手术相关并发症。结果:17例患者中男9例,女8例,年龄33~77岁;真性动脉瘤20例,假性动脉瘤2例;多发3例,单发14例;瘤体位于脾动脉近段3例,中段10例,远段9例。所有患者均成功栓塞,未发生严重手术并发症;术后随访3~36个月,腹部增强CT示脾动脉瘤铸型良好,未见复发、增大或破裂出血。结论:经导管NBCA医用胶联合弹簧圈三明治法栓塞脾动脉瘤成功率高,安全有效。 展开更多
关键词 脾动脉瘤 栓塞 弹簧圈 NBCA医用胶 三明治法
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连续管磨损对防喷盒胶筒密封性能的影响
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作者 陈婷 胡子龙 +2 位作者 马卫国 邓琳 李晨 《润滑与密封》 CAS CSCD 北大核心 2024年第7期115-122,共8页
为研究连续管磨损对防喷盒胶筒密封性能的影响,归纳连续管常见磨损形式并构建其磨损几何模型,以通径为38.1 mm防喷盒胶筒为例,通过实验得到其材料本构模型参数,建立防喷盒胶筒密封连续管的有限元模型;以有效接触应力和最大Mises应力为指... 为研究连续管磨损对防喷盒胶筒密封性能的影响,归纳连续管常见磨损形式并构建其磨损几何模型,以通径为38.1 mm防喷盒胶筒为例,通过实验得到其材料本构模型参数,建立防喷盒胶筒密封连续管的有限元模型;以有效接触应力和最大Mises应力为指标,分析连续管的磨损形式、磨损深度、磨损长度以及偏磨角度对胶筒密封性能的影响。结果表明:连续管偏磨形式对胶筒密封性能影响较大,连续管偏磨段长度大于胶筒高度且偏磨深度大于1 mm时,胶筒密封能力会出现不能满足井口密封要求的情况;偏磨角度会影响胶筒的应力分布,从而影响密封性能。 展开更多
关键词 连续管 磨损 防喷盒 胶筒 密封性能
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双耦合SP-S补偿紧凑型抗偏移WPT系统
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作者 谢文燕 陈为 +1 位作者 陈庆彬 江彦伟 《中国电机工程学报》 EI CSCD 北大核心 2024年第2期714-724,I0024,共12页
在无线电能传输(wireless power transfer,WPT)系统中,偏移是不可避免的,偏移会引起系统参数的变化从而影响系统的传输性能。基于S-S和P-S补偿拓扑,提出一种具有抗偏移特性的双耦合SP-S补偿的紧凑型WPT系统。该系统采用两个同轴布置、... 在无线电能传输(wireless power transfer,WPT)系统中,偏移是不可避免的,偏移会引起系统参数的变化从而影响系统的传输性能。基于S-S和P-S补偿拓扑,提出一种具有抗偏移特性的双耦合SP-S补偿的紧凑型WPT系统。该系统采用两个同轴布置、相互解耦的圆角方形线圈作为能量的发射线圈,其与单一方形接收线圈均有耦合,提升了X方向和Y方向的抗偏移容忍度。通过谐振参数配置使接收线圈在偏移的过程中,一个线圈回路的输出增加,另一个线圈回路输出减少,从而使系统输出随接收线圈位置偏移波动平缓。提出方形解耦线圈结构参数的设计方法,并分析发射端并联补偿电容对输出抗偏移性能的影响。最后,搭建实验平台验证该方法的有效性与系统的抗偏移能力。 展开更多
关键词 抗偏移 无线电能传输 解耦线圈 双耦合
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大推力音圈电机结构优化与实验验证
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作者 王金林 丁磊 +2 位作者 闵为 庄广荧 莫善楠 《液压与气动》 北大核心 2024年第8期37-45,共9页
针对高性能电液比例阀所需的大推力驱动器,提出了5种结构形式音圈电机,利用电磁仿真工具ANSYS Maxwell,对不同结构的音圈电机的推力和磁场分布特征进行了计算,分析铁芯半径和线圈位移对不同结构的音圈电机推力和磁场分布的影响。结果表... 针对高性能电液比例阀所需的大推力驱动器,提出了5种结构形式音圈电机,利用电磁仿真工具ANSYS Maxwell,对不同结构的音圈电机的推力和磁场分布特征进行了计算,分析铁芯半径和线圈位移对不同结构的音圈电机推力和磁场分布的影响。结果表明,5种结构中内磁式无铁芯、线圈紧贴外壳、永磁体分段设计的结构有最大推力,可达75.29 N,并通过实验得到了验证;在永磁体两侧添加导磁环以及适当分段永磁体,均能有效提升音圈电机的推力。 展开更多
关键词 音圈电机 推力 结构优化 电磁场仿真
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