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A review of superplastic magnesium alloys:Focusing on alloying strategy,grain structure control and deformation mechanisms 被引量:2
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作者 Siqing Wang Min Zha +5 位作者 Hailong Jia Yajie Yang Dawei Wang Cheng Wang Yipeng Gao Hui-Yuan Wang 《Journal of Materials Science & Technology》 2025年第8期303-319,共17页
In response to the urgent demand for lightweight,magnesium(Mg)alloys have garnered considerable attention owing to their low density.Nonetheless,the intrinsic poor room-temperature formability of Mg alloys remains a m... In response to the urgent demand for lightweight,magnesium(Mg)alloys have garnered considerable attention owing to their low density.Nonetheless,the intrinsic poor room-temperature formability of Mg alloys remains a major obstacle in shaping precise complex components,necessitating the development of superplastic Mg alloys.Excellent superplasticity is usually acquired in high-alloyed Mg alloys with enhanced microstructural thermal stability facilitated by abundant optimized second-phase particles.While for cost-effective low-alloyed Mg alloys lacking particles,regulating solute segregation has emerged as a promising approach to achieve superplasticity recently.Moreover,the potential of bimodal-grained Mg alloys for superplastic deformation has been revealed,expanding the options for designing superplastic materials beyond the conventional approach of fine-grained microstructures.This study reviews significant developments in superplastic Mg alloys from the view of alloying strategies,grain structure control and deformation mechanisms,with potential implications for future research and industrial applications of superplastic Mg alloys. 展开更多
关键词 Mg alloys SUPERPLASTICITY Second-phase particles Solute segregation Microstructure control
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Natural products for the treatment of age-related macular degeneration:New insights focusing on mitochondrial quality control and cGAS/STING pathway
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作者 Xuelu Xie Shan Lian +6 位作者 Wenyong Yang Sheng He Jingqiu He Yuke Wang Yan Zeng Fang Lu Jingwen Jiang 《Journal of Pharmaceutical Analysis》 2025年第5期956-973,共18页
Age-related macular degeneration(AMD)is a disease that affects the vision of elderly individuals worldwide.Although current therapeutics have shown effectiveness against AMD,some patients may remain unresponsive and c... Age-related macular degeneration(AMD)is a disease that affects the vision of elderly individuals worldwide.Although current therapeutics have shown effectiveness against AMD,some patients may remain unresponsive and continue to experience disease progression.Therefore,in-depth knowledge of the mechanism underlying AMD pathogenesis is urgently required to identify potential drug targets for AMD treatment.Recently,studies have suggested that dysfunction of mitochondria can lead to the aggregation of reactive oxygen species(ROS)and activation of the cyclic GMP-AMP synthase(cGAS)/stimulator of interferon genes(STING)innate immunity pathways,ultimately resulting in sterile inflammation and cell death in various cells,such as cardiomyocytes and macrophages.Therefore,combining strategies targeting mitochondrial dysfunction and inflammatory mediators may hold great potential in facilitating AMD management.Notably,emerging evidence indicates that natural products targeting mitochondrial quality control(MQC)and the cGAS/STING innate immunity pathways exhibit promise in treating AMD.Here,we summarize phytochemicals that could directly or indirectly influence the MQC and the cGAS/STING innate immunity pathways,as well as their interconnected mediators,which have the potential to mitigate oxidative stress and suppress excessive inflammatory responses,thereby hoping to offer new insights into therapeutic interventions for AMD treatment. 展开更多
关键词 Age-related macular degeneration PHYTOCHEMICALS Mitochondrial quality control MITOPHAGY Mitochondrial biogenesis cGAS/STING
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Monolithically 3D-nanoprinted millimeter-scale lens actuator for dynamic focus control in optical systems
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作者 Florian Lux Aybuke Calikoglu Çağlar Ataman 《Advanced Photonics Nexus》 2025年第4期140-153,共14页
Three-dimensional(3D)nanoprinting via two-photon polymerization offers unparalleled design flexibility and precision,thereby enabling rapid prototyping of advanced micro-optical elements and systems that have found im... Three-dimensional(3D)nanoprinting via two-photon polymerization offers unparalleled design flexibility and precision,thereby enabling rapid prototyping of advanced micro-optical elements and systems that have found important applications in endomicroscopy and biomedical imaging.The potential of this versatile tool for monolithic manufacturing of dynamic micro-opto-electro-mechanical systems(MOEMSs),however,has not yet been sufficiently explored.This work introduces a 3D-nanoprinted lens actuator with a large optical aperture,optimized for remote focusing in miniaturized imaging systems.The device integrates orthoplanar linear motion springs,a self-aligned sintered micro-magnet,and a monolithic lens,actuated by dual microcoils for uniaxial motion.The use of 3D nanoprinting allows complete design freedom for the integrated optical lens,whereas the monolithic fabrication ensures inherent alignment of the lens with the mechanical elements.With a lens diameter of 1.4 mm and a compact footprint of 5.74 mm,it achieves high mechanical robustness at resonant frequencies exceeding 300 Hz while still providing a large displacement range of 200μm(±100μm).A comprehensive analysis of optical and mechanical performance,including the effects of coil temperature and polymer viscoelasticity,demonstrates its advantages over conventional micro-electro-mechanical system actuators,showcasing its potential for next-generation imaging applications. 展开更多
关键词 micro-electro-mechanical system scanner two-photon polymerization 3D nanoprinting dynamic focus control electromagnetic actuation
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A New Inversion-free Iterative Method for Solving the Nonlinear Matrix Equation and Its Application in Optimal Control
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作者 GAO Xiangyu XIE Weiwei ZHANG Lina 《应用数学》 北大核心 2026年第1期143-150,共8页
In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to ... In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to obtain the maximal positive definite solution of nonlinear matrix equation X+A^(*)X|^(-α)A=Q with the case 0<α≤1.Based on this method,a new iterative algorithm is developed,and its convergence proof is given.Finally,two numerical examples are provided to show the effectiveness of the proposed method. 展开更多
关键词 Nonlinear matrix equation Maximal positive definite solution Inversion-free iterative method Optimal control
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Strategic and Regional Investigation of the Exact Controllability of the Vibrating Plate Equation on a Regular Domain
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作者 Mouhamadou NGOM Cheikh SECK 《Journal of Mathematical Research with Applications》 2026年第1期134-142,共9页
In this paper,we define for the trace operator,the solution of certain models of vibrating plates standards with initial data in a strategic region spaces of weak regularities.Indeed,we know that the notion of regiona... In this paper,we define for the trace operator,the solution of certain models of vibrating plates standards with initial data in a strategic region spaces of weak regularities.Indeed,we know that the notion of regional controllability is more adapted to systems described by dynamic systems.Regional controllability results in a strategic area were established for vibrating plates by the Hilbertian Uniqueness Method. 展开更多
关键词 exact controllability vibrating plates strategic regional control Hilbert uniqueness method
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Optimizing risk management for post-amputation wound complications in diabetic patients: Focus on glycemic and immunosuppressive control
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作者 Zhi-Peng Li Jin-Ke Sun +1 位作者 Wei-Ping Fu Chang-Jiang Zhang 《World Journal of Diabetes》 2025年第3期277-283,共7页
This study highlights the importance of identifying and addressing risk factors associated with wound complications following transtibial amputation in diabetic patients.These amputations,often necessitated by severe ... This study highlights the importance of identifying and addressing risk factors associated with wound complications following transtibial amputation in diabetic patients.These amputations,often necessitated by severe diabetic foot ulcers,carry significant risks of postoperative complications such as infection and delayed wound healing.Elevated hemoglobin A1c levels,indicative of poor glycemic control,and a history of kidney transplantation,due to required immunosuppressive therapy,are key factors influencing these outcomes.This paper emphasizes the need for enhanced glycemic management and personalized postoperative care,particularly for immunocompromised individuals,to minimize complications and improve patient prognosis.Future research should focus on prospective studies to validate targeted interventions and optimize care strategies,ultimately aiming to reduce the healthcare burden associated with diabetic foot complications. 展开更多
关键词 Transtibial amputation Diabetic foot Wound complications Risk factors Glycemic control Hemoglobin A1c Immunosuppressive therapy Kidney transplantation Personalized care Postoperative outcomes
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基于FOC矢量控制的AGV小车无刷电机控制器设计
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作者 杨立宏 袁夫全 代允 《现代信息科技》 2025年第20期12-16,共5页
自动引导运输车(AGV)在智能化工厂仓储运输中发挥着至关重要的作用,可大幅降低人力成本、提高运输效率。无刷电机具有高效节能、可靠稳定等特点,已逐渐应用于AGV小车的驱动系统。文章设计了一种基于矢量控制(FOC)与PID控制算法的无刷电... 自动引导运输车(AGV)在智能化工厂仓储运输中发挥着至关重要的作用,可大幅降低人力成本、提高运输效率。无刷电机具有高效节能、可靠稳定等特点,已逐渐应用于AGV小车的驱动系统。文章设计了一种基于矢量控制(FOC)与PID控制算法的无刷电机控制器,通过霍尔传感器获取无刷电机转子位置信息,基于矢量控制(FOC)算法使电机在高效率下运行,并借助PID调节实现电机速度与电流的双闭环控制。经编程实际测试,验证了该控制方案的可行性,可有效提升AGV小车的运输效率与运行稳定性。 展开更多
关键词 无刷电机 矢量控制foc PID控制算法 双闭环
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A method of laser focusing control in microlaser-induced breakdown spectroscopy 被引量:6
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作者 Wei WANG Lanxiang SUN +3 位作者 Peng ZHANG Liming ZHENG Lifeng QI Wei DONG 《Plasma Science and Technology》 SCIE EI CAS CSCD 2019年第3期31-39,共9页
This paper presents a method for the automatic adjustment of the laser defocusing amount in micro-laser-induced breakdown spectroscopy. A microscopic optical imaging system consisting of a CCD camera and a 20× ob... This paper presents a method for the automatic adjustment of the laser defocusing amount in micro-laser-induced breakdown spectroscopy. A microscopic optical imaging system consisting of a CCD camera and a 20× objective lens was adopted to realize the method. The real-time auto-focusing of the system was achieved by detecting the effective pixels of the light spot generated by the laser pointer. The focusing accuracy of the method could achieve 3 μm. The element concentrations of Mn and Ni in low-alloy steels were analyzed at a crater diameter of about 35 μm using the presented method. After using the presented method, the determination coefficients of Mn and Ni both exceeded 0.997, with the root-mean-square errors being 0.0133 and 0.0395, respectively. Scanning analysis was performed on the inclined plane and the curved surface by means of focusing control and non-focusing control. Ten characteristic spectral lines of Fe were selected as the analysis lines. With the focusing control, the average relative standard deviations obtained on the inclined plane and curved surface were both less than 5%, and much less than the values without focusing control, 14.6% and 40.39%. 展开更多
关键词 LIBS MICROANALYSIS ablation CRATER focUSING control
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An overview of various control benchmarks with a focus on automotive control 被引量:2
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作者 Lars ERIKSSON 《Control Theory and Technology》 EI CSCD 2019年第2期121-130,共10页
There exists a gap between control theory and control practice,i.e.,all control methods suggested by researchers are not implemented in real systems and,on the other hand,many important in dustrial problems are not st... There exists a gap between control theory and control practice,i.e.,all control methods suggested by researchers are not implemented in real systems and,on the other hand,many important in dustrial problems are not studied in the academic research.Benchmark problems can help close this gap and provide many opportunities for members in both the controls theory and application communities.The goal is to survey and give pointers to different general controls and modeling related benchmark problems that can serve as inspiration for future benchmarks and then specifically focus the benchmark coverage on automotive control engineering application.In the paper reflections are given on how different categories of benchmark designers,benchmark solvers and third part users can benefit from providing,solving,and studying benchmark problems.The paper also collects information about several benchmark problems and gives pointers to papers than give more detailed information about different problems that have been presented. 展开更多
关键词 BENCHMARK AUTOMOTIVE control robust control ROBOTICS engine control POWERTRAIN control system identification
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Effectiveness of peripheral defocus spectacle lenses in myopia control: a Meta-analysis and systematic review 被引量:3
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作者 Ji-Xian Ma Si-Wen Tian Qiu-Ping Liu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2022年第10期1699-1706,共8页
AIM: To evaluate the effectiveness of peripheral defocus spectacle lenses(PDLs) in myopia control. METHODS: Literature retrieval on Pub Med, Cochrane Library, Embase, and Web of Science databases, and the search time ... AIM: To evaluate the effectiveness of peripheral defocus spectacle lenses(PDLs) in myopia control. METHODS: Literature retrieval on Pub Med, Cochrane Library, Embase, and Web of Science databases, and the search time limit was from the establishment of each database to December 29, 2021 were conducted. Change of spherical equivalent refraction(SER) and axial change(AL) were extracted from the literatures that met the inclusion criteria, and Rev Man5.3 software was used for Meta-analysis. RESULTS: A total of 4 randomized controlled trials(RCTs) were included in this Meta-analysis, involving 770 myopic children. The results showed that PDLs could delay the progression of myopia in children with myopia compared with single vision spectacle lenses(SVLs;WMD=0.21 D, 95%CI: 0.01, 0.41, P=0.04). However, there was no significant difference in controlling the growth of axial length(AL) in myopic children(WMD=-0.10 mm, 95%CI:-0.21, 0.01, P=0.07). The results of the effectiveness of myopia control between the two spectacle lenses showed that PDLs were more effective in controlling the progression of myopia(OR=5.73, 95%CI: 2.58, 12.70, P<0.001) and delaying the growth of AL(OR=44.25, 95%CI: 8.84, 221.58, P<0.001) than SVLs, and the differences were statistically significant. CONCLUSION: PDLs can control the progression of myopia compared with SVLs, but cannot delay the growth of AL, and the effectiveness of PDLs in myopia control better than SVLs. 展开更多
关键词 META-ANALYSIS peripheral defocus spectacle lenses hyperopia defocus myopia defocus myopia control
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Foc TR4侵染对不同抗性香蕉种质淀粉含量的影响 被引量:1
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作者 丁月 尹可锁 +6 位作者 朱酉正捷 郑泗军 徐胜涛 张文龙 冯臣成 尹顺利 刘立娜 《山西农业科学》 2025年第4期140-148,共9页
枯萎病作为一种对香蕉产业具有毁灭性影响的病害,一直是香蕉病害防控关注的焦点。为探究根组织中淀粉含量在寄主香蕉响应枯萎病菌侵染过程中的作用,将6个不同抗病、感病香蕉种质人工接种枯萎病菌4号生理小种热带型(Foc TR4),测定接种后... 枯萎病作为一种对香蕉产业具有毁灭性影响的病害,一直是香蕉病害防控关注的焦点。为探究根组织中淀粉含量在寄主香蕉响应枯萎病菌侵染过程中的作用,将6个不同抗病、感病香蕉种质人工接种枯萎病菌4号生理小种热带型(Foc TR4),测定接种后不同时间点根组织中的淀粉含量,并分析其动态变化规律。结果表明,不同香蕉种质在接种Foc TR4后,根组织中的淀粉含量均呈上升趋势;相比感病种质,抗病种质淀粉含量对Foc TR4侵染的响应变化更明显,在测定时间范围内,达到峰值的时间比感病种质提前了7 d。抗病种质Pahang、Mbwazirume、GCTCV-119的淀粉含量在7、14、21、28 d的平均变化率分别为81.0%、97.0%、127.6%、94.8%,高于感病种质Gros Michel、Ibwi、Baxi Jiao的平均变化率42.5%、32.1%、46.1%、72.9%,表明在病原菌侵染过程中,香蕉根组织淀粉含量变化率与枯萎病抗性显著正相关。综上,根组织淀粉在香蕉响应枯萎病菌侵染的机制中具有重要功能,不同香蕉种质根组织淀粉含量的变化率决定了其对Foc TR4的抗性。 展开更多
关键词 枯萎病 香蕉 淀粉含量 抗病 感病 focTR4 根组织
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Bloodletting puncture in the treatment of acute ischemic stroke:protocol for a mixed-method study of a multi-center randomized controlled trial and focus group 被引量:1
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作者 DAI Zeqi LIAO Xing +3 位作者 GUAN Yueyue ZENG Zixiu TANG Jun HU Jing 《Journal of Traditional Chinese Medicine》 SCIE CSCD 2023年第6期1259-1267,共9页
This study is to investigate the effectiveness and safety of bloodletting puncture(BP)for acute ischemic stroke(AIS)when used in combination with standard treatment,as well as the patients'feelings and attitudes t... This study is to investigate the effectiveness and safety of bloodletting puncture(BP)for acute ischemic stroke(AIS)when used in combination with standard treatment,as well as the patients'feelings and attitudes toward the treatment.This is a mixed method research which includes a multi-center,superiority,randomized controlled clinical trial,and focus group interview.A total of 360 AIS participants will be enrolled.They will be randomized into one of the following two groups for 7 d:(a)BP with standard treatment group(n=180);(b)standard treatment group(n=180).The primary outcome will be National Institute of Health stroke scale(NIHSS)score at day 7 after treatment.Secondary outcomes will be changes of Glasgow Coma Scale score,NIHSS score,mRS and Traditional Chinese Medicine syndrome score from baseline to 7,14,and 30 d after treatment,recurrence rate and all-cause mortality rate within 30 d,and the safety assessments.The focus group will be conducted with a purposive sample of 1-2 acupuncturists and 1-2 patients respectively at each center at 7 and 30 d after treatment.We designed a mixed method study to evaluate the effect of BP,an acupuncture therapy for patients with AIS.If the findings of this study confirm the effectiveness of BP to reduce the NIHSS score and other related outcomes and patients are willing to accept the therapy,we believe this study will help the implementation of this therapy in clinical practice,and provide new evidence for the treatment of AIS. 展开更多
关键词 BLOODLETTING PUNCTURES ischemic stroke equivalence trial randomized controlled trial focus groups clinical protocols
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基于扩展卡尔曼滤波FOC矢量舵机三环控制算法研究
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作者 姚向国 陈继文 +2 位作者 吴国安 李大勇 王会彬 《机电产品开发与创新》 2025年第4期95-99,共5页
针对舵机控制过程中实现最优运行的问题,提出基于扩展卡尔曼滤波FOC矢量舵机三环控制算法研究。建立相应的数学模型,设计三环控制结构,包括外环位置控制、中环速度控制和内环电流控制,以保证系统的稳定性与快速响应。在此基础上,经扩展... 针对舵机控制过程中实现最优运行的问题,提出基于扩展卡尔曼滤波FOC矢量舵机三环控制算法研究。建立相应的数学模型,设计三环控制结构,包括外环位置控制、中环速度控制和内环电流控制,以保证系统的稳定性与快速响应。在此基础上,经扩展卡尔曼滤波处理,对系统状态进行实时估计,有效消除传感器噪声对控制精度的影响,采用仿真方法验证该控制策略的有效性。通过仿真实验结果表明,基于EKF的FOC矢量舵机三环控制算法在定位精度、响应速度和抗干扰能力方面均优于传统控制方法。 展开更多
关键词 扩展卡尔曼滤波 三环控制 foc 舵机
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Focusing Properties of Partially Coherent Controllable Dark-Hollow Beams through a Thin Lens 被引量:1
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作者 曾祥梅 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第7期71-75,共5页
Analytical propagation formulas are derived for partially coherent controllable dark-hollow beams (CDHBs) through a thin lens based on the generalized Huygens-Fresnel integral. The expressions of the position for ma... Analytical propagation formulas are derived for partially coherent controllable dark-hollow beams (CDHBs) through a thin lens based on the generalized Huygens-Fresnel integral. The expressions of the position for maximum irradiance on-axis and the relative focal shift are evaluated by the analytical propagation formulas. Our numerical results show that both the relative focal shift and the effective beam width of focused partially coherent CDHBs are mainly determined by the initial transverse coherence width 6g and the Fresnel number Nw, which are also affected by the changes of both the dark-size adjusting parameter p and the order N of CDHBs. 展开更多
关键词 exp focusing Properties of Partially Coherent controllable Dark-Hollow Beams through a Thin Lens
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Coordinated Control Strategy of New Energy Power Generation System with Hybrid Energy Storage Unit 被引量:1
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作者 Yun Zhang Zifen Han +2 位作者 Biao Tian Ning Chen Yi Fan 《Energy Engineering》 EI 2025年第1期167-184,共18页
The new energy power generation is becoming increasingly important in the power system.Such as photovoltaic power generation has become a research hotspot,however,due to the characteristics of light radiation changes,... The new energy power generation is becoming increasingly important in the power system.Such as photovoltaic power generation has become a research hotspot,however,due to the characteristics of light radiation changes,photovoltaic power generation is unstable and random,resulting in a low utilization rate and directly affecting the stability of the power grid.To solve this problem,this paper proposes a coordinated control strategy for a newenergy power generation system with a hybrid energy storage unit based on the lithium iron phosphate-supercapacitor hybrid energy storage unit.Firstly,the variational mode decomposition algorithm is used to separate the high and low frequencies of the power signal,which is conducive to the rapid and accurate suppression of the power fluctuation of the energy storage system.Secondly,the fuzzy control algorithm is introduced to balance the power between energy storage.In this paper,the actual data is used for simulation,and the simulation results show that the strategy realizes the effective suppression of the bus voltage fluctuation and the accurate control of the internal state of the energy storage unit,effectively avoiding problems such as overshoot and over-discharge,and can significantly improve the stability of the photovoltaic power generation systemand the stability of the Direct Current bus.It is of great significance to promote the development of collaborative control technology for photovoltaic hybrid energy storage units. 展开更多
关键词 Photovoltaic power suppression hybrid energy storage unit variationalmodal decomposition fuzzy control power distribution control
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Corneal Wavefront Aberrations in Patients Wearing Multifocal Soft Contact Lenses for Myopia Control
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作者 Frank Spors Donald J. Egan +3 位作者 Jie Shen Lance E. McNaughton Stuart Mann Neil M. Patel 《Open Journal of Ophthalmology》 2012年第3期45-53,共9页
Purpose: The purpose of this study was to evaluate the change in corneal wavefront aberrations in young adults who have been fit with multifocal soft contact lenses for myopia progression control. Findings have been a... Purpose: The purpose of this study was to evaluate the change in corneal wavefront aberrations in young adults who have been fit with multifocal soft contact lenses for myopia progression control. Findings have been analyzed for statistical significance and clinical relevance and compared to reportedly successful Orthokeratology outcomes. Methods: The dominant eye of 40 participants (27 women, 13 men;mean age 27.3 ± 3.2 years;range 23 to 39 years) was fit with Proclear Multifocal center distance lenses (Coopervision, Pleasanton, USA) having a variety of distance powers and reading additions. Refractive errors were limited to a range of –6.00 D up to +1.00 D of sphere, and no greater than –1.00 D of cylinder. Corneal wavefront measurements were performed over 6 mm diameters with a Zeiss Atlas 9000 corneal topographer (Zeiss Meditec, Dublin, USA) prior to, and following lens fitting. Data were converted into rectangular Fourier optics terms M, J0, J45 and RMS values for each reading addition were statistically analyzed. Following evaluation of statistical significance and clinical relevance, results were compared to published data from successful Orthokeratology treatments. Results: Statistically significant changes in higher order aberrations were detected for lenses of all reading additions. Lens groups with higher Add-powers demonstrated stronger changes with increased significance. Final RMS values relating to 2nd, 3rd and 4th Zernike Orders reached clinical significance with a wavefront error of 0.10 μm, the equivalent of 0.25D. Moreover, as Add-powers increased, 3rd and 4th order aberrations likewise showed an increase. Pre-fitting astigmatism values accounted for the highest recorded aberrations and remained predominantly unchanged. Conclusion: Proclear Multifocal center-distance contact lenses were found to increase higher order wavefront aberrations in a manner dependent on their Add-power. In comparison to successful Orthokeratology outcomes, the amounts of resulting aberrations are notably different. 展开更多
关键词 MULTIfocAL Soft Contact Lenses Wavefront Aberrations MYOPIA MYOPIA Progression control ORTHOKERATOLOGY ZERNIKE Polynomials
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Medical aspects of terrorist bombings: A focus on damage control surgery and damage control resuscitation
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作者 Ventsislav M Mutafchiyski Georgi I Popivanov Kirien C Kjossev 《Journal of Medical Colleges of PLA(China)》 CAS 2014年第2期103-108,共6页
Although terrorist bombings have tormented the world for a long time, currently they have reached unprecedented levels and become a continuous threat without borders, race or age. Almost all of them are caused by impr... Although terrorist bombings have tormented the world for a long time, currently they have reached unprecedented levels and become a continuous threat without borders, race or age. Almost all of them are caused by improvised explosive devices. The unpredictability of the terrorist bombings, leading to simultaneous generation of a large number of casualties and severe "multidimensional" blast trauma require a constant vigilance and preparedness of every hospital worldwide. Approximately 1.0%-2.6% of all trauma patients and 7% of the combat casualties require a massive blood transfusion. Coagulopathy is presented in 65% of them with mortality exceeding 50%. Damage control resuscitation is a novel approach, developed in the military practice for treatment of this subgroup of trauma patients. The comparison with the conventional approach revealed mortality reduction with 40%-74%, lower frequency of abdominal compartment syndrome(8% vs 16%), sepsis(9% vs 20%), multiorgan failure(16% vs 37%) and a significant reduction of resuscitation volumes, both crystalloids and blood products. Damage control surgery(DCS) and damage control resuscitation(DCR) are promising new approaches, contributing for the mortality reduction among the most severely wounded patients. Despite the lack of consensus about the optimal ratio of the blood products and the possible influence of the survival bias, we think that DCR carries survival benefit and recommend it in trauma patients with exsanguinating bleeding. 展开更多
关键词 terrorist bombings traumatic coagulopathy damage control resuscitation
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An asymmetrically variable wingtip anhedral angles morphing aircraft based on incremental sliding mode control:Improving lateral maneuver capability 被引量:2
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作者 Xiaodong LIU Yong XU Jianqiao LUO 《Chinese Journal of Aeronautics》 2025年第1期455-470,共16页
This paper presents the design of an asymmetrically variable wingtip anhedral angles morphing aircraft,inspired by biomimetic mechanisms,to enhance lateral maneuver capability.Firstly,we establish a lateral dynamic mo... This paper presents the design of an asymmetrically variable wingtip anhedral angles morphing aircraft,inspired by biomimetic mechanisms,to enhance lateral maneuver capability.Firstly,we establish a lateral dynamic model considering additional forces and moments resulting during the morphing process,and convert it into a Multiple Input Multiple Output(MIMO)virtual control system by importing virtual inputs.Secondly,a classical dynamics inversion controller is designed for the outer-loop system.A new Global Fast Terminal Incremental Sliding Mode Controller(NDO-GFTISMC)is proposed for the inner-loop system,in which an adaptive law is implemented to weaken control surface chattering,and a Nonlinear Disturbance Observer(NDO)is integrated to compensate for unknown disturbances.The whole control system is proven semiglobally uniformly ultimately bounded based on the multi-Lyapunov function method.Furthermore,we consider tracking errors and self-characteristics of actuators,a quadratic programmingbased dynamic control allocation law is designed,which allocates virtual control inputs to the asymmetrically deformed wingtip and rudder.Actuator dynamic models are incorporated to ensure physical realizability of designed allocation law.Finally,comparative experimental results validate the effectiveness of the designed control system and control allocation law.The NDO-GFTISMC features faster convergence,stronger robustness,and 81.25%and 75.0%reduction in maximum state tracking error under uncertainty compared to the Incremental Nonlinear Dynamic Inversion Controller based on NDO(NDO-INDI)and Incremental Sliding Mode Controller based on NDO(NDO-ISMC),respectively.The design of the morphing aircraft significantly enhances lateral maneuver capability,maintaining a substantial control margin during lateral maneuvering,reducing the burden of the rudder surface,and effectively solving the actuator saturation problem of traditional aircraft during lateral maneuvering. 展开更多
关键词 Morphing aircraft Lateral maneuver capability Incremental sliding mode control Multi-Lyapunov function method control theory control allocation law
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Integrated Equipment with Functions of Current Flow Control and Fault Isolation for Multiterminal DC Grids 被引量:1
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作者 Shuo Zhang Guibin Zou 《Energy Engineering》 EI 2025年第1期85-99,共15页
The multi-terminal direct current(DC)grid has extinctive superiorities over the traditional alternating current system in integrating large-scale renewable energy.Both the DC circuit breaker(DCCB)and the current flow ... The multi-terminal direct current(DC)grid has extinctive superiorities over the traditional alternating current system in integrating large-scale renewable energy.Both the DC circuit breaker(DCCB)and the current flow controller(CFC)are demanded to ensure the multiterminal DC grid to operates reliably and flexibly.However,since the CFC and the DCCB are all based on fully controlled semiconductor switches(e.g.,insulated gate bipolar transistor,integrated gate commutated thyristor,etc.),their separation configuration in the multiterminal DC grid will lead to unaffordable implementation costs and conduction power losses.To solve these problems,integrated equipment with both current flow control and fault isolation abilities is proposed,which shares the expensive and duplicated components of CFCs and DCCBs among adjacent lines.In addition,the complicated coordination control of CFCs and DCCBs can be avoided by adopting the integrated equipment in themultiterminal DC grid.In order to examine the current flow control and fault isolation abilities of the integrated equipment,the simulation model of a specific meshed four-terminal DC grid is constructed in the PSCAD/EMTDC software.Finally,the comparison between the integrated equipment and the separate solution is presented a specific result or conclusion needs to be added to the abstract. 展开更多
关键词 Integrated equipment multiterminal direct current grid current flow control fault isolation
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Fault-observer-based iterative learning model predictive controller for trajectory tracking of hypersonic vehicles 被引量:2
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作者 CUI Peng GAO Changsheng AN Ruoming 《Journal of Systems Engineering and Electronics》 2025年第3期803-813,共11页
This work proposes the application of an iterative learning model predictive control(ILMPC)approach based on an adaptive fault observer(FOBILMPC)for fault-tolerant control and trajectory tracking in air-breathing hype... This work proposes the application of an iterative learning model predictive control(ILMPC)approach based on an adaptive fault observer(FOBILMPC)for fault-tolerant control and trajectory tracking in air-breathing hypersonic vehicles.In order to increase the control amount,this online control legislation makes use of model predictive control(MPC)that is based on the concept of iterative learning control(ILC).By using offline data to decrease the linearized model’s faults,the strategy may effectively increase the robustness of the control system and guarantee that disturbances can be suppressed.An adaptive fault observer is created based on the suggested ILMPC approach in order to enhance overall fault tolerance by estimating and compensating for actuator disturbance and fault degree.During the derivation process,a linearized model of longitudinal dynamics is established.The suggested ILMPC approach is likely to be used in the design of hypersonic vehicle control systems since numerical simulations have demonstrated that it can decrease tracking error and speed up convergence when compared to the offline controller. 展开更多
关键词 hypersonic vehicle actuator fault tracking control iterative learning control(ILC) model predictive control(MPC) fault observer
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