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A Biomimetic Stress Field Modulation Strategy Inspired by Scorpion Compound Slit Sensilla Enabled High-Accuracy and Low-Power Positioning Sensor for Identifying the Load Incident Angles
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作者 Junqiu Zhang Yu Chen +11 位作者 Haoran Li Jiqi Gao Xiangbo Gu Jiachao Wu Xiaojing Qin Kejun Wang Bin Zhu Daobing Chen Tao Sun Jianhua Fan Zhiwu Han Luquan Ren 《Journal of Bionic Engineering》 2025年第2期727-738,共12页
Numerous arthropods evolve and optimize sensory systems, enabling them to effectively adapt complex and competitive habitats. Typically, scorpions can precisely perceive the prey location with the lowest metabolic rat... Numerous arthropods evolve and optimize sensory systems, enabling them to effectively adapt complex and competitive habitats. Typically, scorpions can precisely perceive the prey location with the lowest metabolic rate among invertebrates. This biological phenomenon contrasts sharply with engineered systems, which generally associates high accuracy with substantial energy consumption. Inspired by the Scorpion Compound Slit Sensilla (SCSS) with a stress field modulation strategy, a bionic positioning sensor with superior precision and minimal power consumption is developed for the first time, which utilizes the particular Minimum Positioning Units (MPUs) to efficiently locate vibration signals. The single MPU of the SCSS can recognize the direction of collinear loads by regulating the stress field distribution and further, the coupling action of three MPUs can realize all-angle vibration monitoring in plane. Experiments demonstrate that the bionic positioning sensor achieves 1.43 degrees of angle-error-free accuracy without additional energy supply. As a proof of concept, two bionic positioning sensors and machine learning algorithm are integrated to provide centimeter (cm)-accuracy target localization, ideally suited for the man-machine interaction. The novel design offers a new mechanism for the design of traditional positioning devices, improving precision and efficiency in both the meta-universe and real-world Internet-connected systems. 展开更多
关键词 Scorpion Compound Slit Sensilla(SCSS) Vibration Source Stress Field modulation strategy High-accuracy and low-power Positioning Sensor Minimum Positioning Unit(MPU)
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Precise Modulation Strategies for Transcranial Magnetic Stimulation:Advances and Future Directions 被引量:10
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作者 Gangliang Zhong Zhengyi Yang Tianzi Jiang 《Neuroscience Bulletin》 SCIE CAS CSCD 2021年第12期1718-1734,共17页
Transcranial magnetic stimulation(TMS)is a popular modulatory technique for the noninvasive diagnosis and therapy of neurological and psychiatric diseases.Unfortunately,current modulation strategies are only modestly ... Transcranial magnetic stimulation(TMS)is a popular modulatory technique for the noninvasive diagnosis and therapy of neurological and psychiatric diseases.Unfortunately,current modulation strategies are only modestly effective.The literature provides strong evidence that the modulatory effects of TMS vary depending on device components and stimulation protocols.These differential effects are important when designing precise modulatory strategies for clinical or research applications.Developments in TMS have been accompanied by advances in combining TMS with neuroimaging techniques,including electroencephalography,functional nearinfrared spectroscopy,functional magnetic resonance imaging,and positron emission tomography.Such studies appear particularly promising as they may not only allow us to probe affected brain areas during TMS but also seem to predict underlying research directions that may enable us to precisely target and remodel impaired cortices or circuits.However,few precise modulation strategies are available,and the long-term safety and efficacy of these strategies need to be confirmed.Here,we review the literature on possible technologies for precise modulation to highlight progress along with limitations with the goal of suggesting future directions for this field. 展开更多
关键词 Transcranial magnetic stimulation modulation strategies Precise stimulation target Coil location Individual treatment paradigm
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Peptide aptamer-mediated modulation of prion protein α-cleavage as treatment strategy for prion and other neurodegenerative diseases 被引量:1
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作者 Antonia N.Klein Erica Corda Sabine Gilch 《Neural Regeneration Research》 SCIE CAS CSCD 2018年第12期2108-2110,共3页
Despite intensive research,most neurodegenerative diseases cannot be cured and for some of them no treatment is available to increase survival or quality of life.Among the latter are prion diseases,fatal and transmiss... Despite intensive research,most neurodegenerative diseases cannot be cured and for some of them no treatment is available to increase survival or quality of life.Among the latter are prion diseases,fatal and transmissible neurodegenerative diseases of humans and other animals. 展开更多
关键词 Peptide aptamer-mediated modulation of prion protein cleavage as treatment strategy for prion and other neurodegenerative diseases
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PI and RST Control Design and Comparison for Matrix Converters Using Venturini Modulation Strategy
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作者 Bekhada Hamane Mamadou Lamine Doumbia +3 位作者 Hicham Chaoui Mohamed Bouhamida Ahmed Chériti Mustapha Benghanem 《Journal of Power and Energy Engineering》 2015年第8期36-54,共19页
This paper presents a thorough design and comparative study of two popular control techniques, i.e., classical Proportional Integral (PI) and RST, for Matrix Converters (MCs) in terms of tracking the reference and rob... This paper presents a thorough design and comparative study of two popular control techniques, i.e., classical Proportional Integral (PI) and RST, for Matrix Converters (MCs) in terms of tracking the reference and robustness. The output signal of MCs is directly affected by unbalanced grid voltage. Some research works have attempted to overcome this problem with PI control. However, this technique is known to offer lower performance when it is used in complex and nonlinear systems. On the other hand, RST control offers better performance, even in case of highly nonlinear systems. Therefore, the RST can achieve better performance to overcome the limitation of PI control of nonlinear systems. In this paper, a RST control method is proposed as output current controller to improve the performance of the MC powered by unbalanced grid voltage. The overall operating principle, Venturini modulation strategy of MC, PI control and characteristics of RST are presented. 展开更多
关键词 Matrix CONVERTER Unbalanced GRID Venturini modulation strategy PI CONTROL RST CONTROL
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A Dual Arm Complementary Hybrid Modulation Strategy Combining NL-SPWM for MMC Applications
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作者 Mingwan Mei Ping Wang +3 位作者 Yanbo Che Zihan Lv Zmarrak Wali Khanand Chao Xing 《Energy Engineering》 EI 2022年第2期591-607,共17页
In the medium voltage direct current(MVDC)transmission system,a small number of MMC sub modules will reduce the power quality.In this paper,based on the research background of Photovoltaic Medium VoltageDirect Current... In the medium voltage direct current(MVDC)transmission system,a small number of MMC sub modules will reduce the power quality.In this paper,based on the research background of Photovoltaic Medium VoltageDirect Current(PV-MVDC)system,aHybrid Modulation Strategy based on theDecoupledDouble SynchronousReference Frame(DDSRF)control strategy is proposed.The dual armcomplementary hybrid modulation combining nearest-level-SPWM(NL-SPWM)can keep the number of SMs in the ON state constant.Then,the corresponding voltage sharing control algorithm of sub module(SM)is introduced.Through theoretical calculation,the modulation strategy can be found to stabilize the DC voltage and reduce the harmonic content.A32-level MMC systemhas been developed to verity that the proposed hybrid modulation strategy and its SM voltage sharing algorithm have the advantages of restraining circulating current and maintaining capacitor voltage balance. 展开更多
关键词 modular multilevel converter modulation strategy dual arm complementary nearest-level-modulation harmonics improvement
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Research on Phase-Shifted Full-Bridge Circuit Based on Frequency and Phase-Shift Synthesis Modulation Strategy
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作者 Mingda Jiang Yanbo Che +2 位作者 Hongfeng Li Muhammad Ishaq Chao Xing 《Energy Engineering》 EI 2022年第2期699-721,共23页
The full-bridge converters usually use transformer leakage inductance and parallel resonant capacitors to achieve smooth current commutation and soft switching functions,which can easily cause problems such as energy ... The full-bridge converters usually use transformer leakage inductance and parallel resonant capacitors to achieve smooth current commutation and soft switching functions,which can easily cause problems such as energy leakage and significant duty cycle loss.This paper designs a novel full-bridge zero-current(FB-ZCS)converter with series resonant capacitors and proposes a frequency and phase-shift synthesis modulation(FPSSM)control strategy based on this topology.Compared with the traditional parallel resonant capacitor circuit,the passive components used are significantly reduced,the structure is simple,and there is only a slight energy loss.By controlling the charging time of the capacitor,it can be achieved without additional switches or auxiliary circuits.The automatic control of capacitor energy based on input current addresses the low efficiency of the traditional control strategies.This paper introduces its principle in detail and verifies it through simulation.Finally,an experimental prototype was built further to demonstrate the feasibility of the theory through experiments.The module can be applied to a photovoltaic DC collection system using input parallel output series(IPOS)cascade to provide a new topology for large-scale,long-distance DC transmission. 展开更多
关键词 Full-bridge converter frequency and phase-shift synthesis modulation(FPSSM) photovoltaic DC collection system control strategy
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Research on Modulation Strategies Based on Multilevel Inverter Universal Hybrid Topology
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作者 ZhouJinghua SuYanmin ShenChuanwen ZhangLin 《Electricity》 2005年第2期53-59,共7页
Based on multi-module-cascaded inverter topology, this study presented a universal multilevel inverter hybrid topology and unified the researches on multilevel inverter topology. According to the freedom of this unive... Based on multi-module-cascaded inverter topology, this study presented a universal multilevel inverter hybrid topology and unified the researches on multilevel inverter topology. According to the freedom of this universal topology, several new hybrid topologies were constructed. Also, based on conventional modulation strategies- multi-carrier SPWM (Sinusoidal Pulse Width Modulation), hybrid modulation strategies were introduced corresponding to hybrid topologies, and a multilevel SVPWM (Space Vector Pulse Width Modulation) technique based on phase-shifted theory was naturally produced. Simulation and experiment results prove that hybrid topologies and corresponding modulation strategies are valid, which lay a foundation for practical application of hybrid multilevel inverter topologies. 展开更多
关键词 MULTILEVEL hybrid topologies MULTI-CARRIER modulation strategies
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A Two-Stage Wiener Degradation Model-Based Approach for Visual Maintenance of Photovoltaic Modules
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作者 Jie Lin Hongchi Shen +1 位作者 Tingting Pei Yan Wu 《Energy Engineering》 2025年第6期2449-2463,共15页
This study proposes a novel visual maintenance method for photovoltaic(PV)modules based on a two-stage Wiener degradation model,addressing the limitations of traditional PV maintenance strategies that often result in ... This study proposes a novel visual maintenance method for photovoltaic(PV)modules based on a two-stage Wiener degradation model,addressing the limitations of traditional PV maintenance strategies that often result in insufficient or excessive maintenance.The approach begins by constructing a two-stage Wiener process performance degradation model and a remaining life prediction model under perfect maintenance conditions using historical degradation data of PV modules.This enables accurate determination of the optimal timing for postfailure corrective maintenance.To optimize the maintenance strategy,the study establishes a comprehensive cost model aimed at minimizing the long-term average cost rate.The model considers multiple cost factors,including inspection costs,preventive maintenance costs,restorative maintenance costs,and penalty costs associated with delayed fault detection.Through this optimization framework,the method determines both the optimal maintenance threshold and the ideal timing for predictive maintenance actions.Comparative analysis demonstrates that the twostage Wiener model provides superior fitting performance compared to conventional linear and nonlinear degradation models.When evaluated against traditional maintenance approaches,including Wiener process-based corrective maintenance strategies and static periodic maintenance strategies,the proposed method demonstrates significant advantages in reducing overall operational costs while extending the effective service life of PV components.The method achieves these improvements through effective coordination between reliability optimization and economic benefit maximization,leading to enhanced power generation performance.These results indicate that the proposed approach offers a more balanced and efficient solution for PV system maintenance. 展开更多
关键词 Photovoltaic module remaining life maintenance strategy Wiener modeling
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Using Targeted Phonon Excitation to Modulate Thermal Conductivity of Boron Nitride
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作者 Dongkai Pan Tianhao Li +3 位作者 Xiao Wan Zhicheng Zong Yangjun Qin Nuo Yang 《Chinese Physics Letters》 2025年第7期449-453,共5页
Recent advancements in thermal conductivity modulating strategies have shown promising enhancements to the thermal management capabilities of two-dimensional materials.In this article,both the iterative Boltzmann tran... Recent advancements in thermal conductivity modulating strategies have shown promising enhancements to the thermal management capabilities of two-dimensional materials.In this article,both the iterative Boltzmann transport equation solution and the two-temperature model were employed to investigate the efficacy of targeted phonon excitation applied to hexagonal boron nitride(hBN).The results indicate significant modifications to hBN's thermal conductivity,achieving increases of up to 30.1%as well as decreases of up to 59.8%.These findings validate the reliability of the strategy,expand its scope of applicability,and establish it as a powerful tool for tailoring thermal properties across a wider range of fields. 展开更多
关键词 thermal conductivityachieving thermal management capabilities boron nitride targeted phonon excitation iterative boltzmann transport equation solution hexagonal boron nitride hbn thermal conductivity modulating strategies thermal conductivity
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Design and modulation principles of molybdenum carbide-based materials for green hydrogen evolution 被引量:2
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作者 Jing-Qi Chi Min Yang +3 位作者 Yong-Ming Chai Zhi Yang Lei Wang Bin Dong 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第9期398-423,I0012,共27页
The green production of hydrogen from electrocatalytic water splitting is an important base and promising direction for the future of the large-scale application of hydrogen energy.The key of green hydrogen evolution ... The green production of hydrogen from electrocatalytic water splitting is an important base and promising direction for the future of the large-scale application of hydrogen energy.The key of green hydrogen evolution depends on the development of low-cost and highly active electrocatalysts.Molybdenum carbides(MoxC),as a typical of earth-abundant transition-metal material,have accumulated great attention due to their low cost,earth abundance,electrical conductivity,similar d-band state to Pt,and regulated morphology/electronic structures.In this paper,recent researches focusing on MoxC for efficient HER in a wide pH range are summarized from respects of modulation of unique morphology,electronic structure,and electrode interface step by step.Briefly,modulation of morphology influence the apparent activity of catalyst,modulation of electronic structure of active sites by heteroatom doping and designing heterointerface boost intrinsic HER kinetics,and modulation of electrode interface via hybridization of MoxC structures with carbon materials can ensure the fast electron transfer and boost the activity.Besides the above methods discussed,perspective and challenges of designing MoxC as the substitute of Pt-based electrocatalyst for practical hydrogen generation in a wide pH range are pointed out. 展开更多
关键词 Molybdenum carbides CLASSIFICATION ELECTROCATALYST modulation strategy Hydrogen evolution
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A Novel Approach of Hybrid Genetic Optimization with Elite Ant Colony:Application in the Modulation Recognition
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作者 LIU Shu WANG Hongyuan LANG Liang 《Wuhan University Journal of Natural Sciences》 CAS 2011年第1期43-48,共6页
A novel approach (HGO-EAC) for hybrid genetic op-timization (GO) with elite ant colony (EAC) is proposed for the automatic modulation recognition of communication signals,through which we improve the basic ant c... A novel approach (HGO-EAC) for hybrid genetic op-timization (GO) with elite ant colony (EAC) is proposed for the automatic modulation recognition of communication signals,through which we improve the basic ant colony algorithms by referencing elite strategy and present a new fusion strategy for genetic optimization and elite ant colony. This approach is used to train the neural networks as the classifier for modulation. Simula-tion results indicate good performance on an additive white Gaus-sian noise (AWGN) channel,with recognition rate reaching to 70% especially for CW even at signal-to-noise ratios as low as 5 dB. This approach can achieve a high recognition rate for the typical modulations such as CW,4ASK,4FSK,BPSK,and QAM16. Test result shows that it has better performance than BP algorithm and basic ant colony algorithms by achieving faster training and stronger robustness. 展开更多
关键词 elite ant colony fusion strategy genetic optimization neural networks classification performance modulation recognition
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Research on marketing module and competitive strategy of E-Business Based on the VIP Website
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作者 Zuo Teng Tian Shuge Chang Yue 《International English Education Research》 2015年第5期101-103,共3页
E-Business now is developing fast in China and the development of E-Business strategy is crucial as the right strategy can make the E-Business select the correct direction and get a better development. In this paper, ... E-Business now is developing fast in China and the development of E-Business strategy is crucial as the right strategy can make the E-Business select the correct direction and get a better development. In this paper, combined with SWOT parameters module, we will make a thorough research on the strategies used by Vip.eom from different angles. After this research, we will have a good understanding of strategies used by VIP website and learn to make better decisions in the e-business world. 展开更多
关键词 VIP Website SWOT module Competitive strategy
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Harnessing immunity:Immunomodulatory therapies in COVID-19
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作者 Tsvetelina Velikova Hristo Valkov +3 位作者 Anita Aleksandrova Monika Peshevska-Sekulovska Metodija Sekulovski Russka Shumnalieva 《World Journal of Virology》 2024年第2期34-47,共14页
An overly exuberant immune response,characterized by a cytokine storm and uncontrolled inflammation,has been identified as a significant driver of severe coronavirus disease 2019(COVID-19)cases.Consequently,decipherin... An overly exuberant immune response,characterized by a cytokine storm and uncontrolled inflammation,has been identified as a significant driver of severe coronavirus disease 2019(COVID-19)cases.Consequently,deciphering the intricacies of immune dysregulation in COVID-19 is imperative to identify specific targets for intervention and modulation.With these delicate dynamics in mind,immunomodulatory therapies have emerged as a promising avenue for miti-gating the challenges posed by COVID-19.Precision in manipulating immune pathways presents an opportunity to alter the host response,optimizing antiviral defenses while curbing deleterious inflammation.This review article compre-hensively analyzes immunomodulatory interventions in managing COVID-19.We explore diverse approaches to mitigating the hyperactive immune response and its impact,from corticosteroids and non-steroidal drugs to targeted biologics,including anti-viral drugs,cytokine inhibitors,JAK inhibitors,convalescent plasma,monoclonal antibodies(mAbs)to severe acute respiratory syndrome coronavirus 2,cell-based therapies(i.e.,CAR T,etc.).By summarizing the current evidence,we aim to provide a clear roadmap for clinicians and researchers navigating the complex landscape of immunomodulation in COVID-19 treatment.CS Glucocorticoids are among the most widely prescribed drugs with their immune-suppressive and anti-inflammatory effect[84].The current guidelines for the treatment of COVID-19 recommend against the use of dexamethasone or other systemic CS in non-hospitalized patients in the absence of another indication[70].The RECOVERY trial demonstrates the reduced 28-d mortality among hospitalized patients with COVID-19 using dexamethasone compared to the usual standard of care,along with other investigators,such as Ahmed and Hassan[85].The benefit of dexamethasone was seen only among participants receiving either oxygen alone or invasive mechanical ventilation at randomization but not among those receiving no respiratory support at enrollment[85].In a systematic review and meta-analysis,Albuquerque et al[86]showed that in comparison to tocilizumab,baricitinib,and sarilumab are associated with high probabilities of similar mortality reductions among hospitalized COVID-19 concurrently treated with CS.As a result of the absence of SARS-CoV-2-specific antiviral medications,the effectiveness of COVID-19 treatments is reduced.Several COVID-19 therapies are now under investigation.However,the majority of them lack specificity,efficacy,and safety[87].Immunotherapy is a ground-breaking medical treatment that manipulates the immune system to fight diseases.Translational research is rapidly progressing,recognized as a significant breakthrough in 2013[88].Among the immunotherapeutic options for treating COVID-19 are Immunoglobulin,CP,antibodies,mAbs(mAbs),NK cells,T cells,TLR,cytokine therapies and immune modulators. 展开更多
关键词 IMMUNOmodulation COVID-19 SARS-CoV-2 IMMUNOTHERAPY Antiviral immune response Cytokine storm Adaptive immunity Therapeutic strategies Immune modulators Viral infection Host immune response
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光-储电站参与多应用场景的日前-日内协同滚动优化策略 被引量:2
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作者 刘自发 李昆阳 郑司琪 《电网技术》 北大核心 2025年第1期198-208,I0079,共12页
光伏电站和储能系统联合运行可以从电源侧减少电站出力不确定性,提高电网稳定性。当前光-储电站参与的应用场景较为单一,无法同时兼顾一次、二次调频以及联合售电。针对这个问题,基于“两个细则”的考核规定,提出一种考虑电能量市场和... 光伏电站和储能系统联合运行可以从电源侧减少电站出力不确定性,提高电网稳定性。当前光-储电站参与的应用场景较为单一,无法同时兼顾一次、二次调频以及联合售电。针对这个问题,基于“两个细则”的考核规定,提出一种考虑电能量市场和一、二次调频服务的具有多场景兼容性的日前-日内滚动优化运行策略。首先,分析了一、二次调频信号特性,提出了多应用场景调度分辨率下的光伏电站混合储能日前-日内协同优化策略框架。然后,以场站联合收益最大为目标,建立了计及储能二次调频能力的日前优化模型,并在日内阶段考虑实际各场景出力优先级,动态滚动优化求解得到储能系统运行计划。最后,利用黑龙江大庆地区某光伏电站实际数据进行了仿真验证,并对模型进行了灵敏度分析,算例表明所提出的优化策略能够发挥不同储能资源的调度潜力,可有效提升电站上报准确率以及调频能力。 展开更多
关键词 光-储电站 混合储能 一次调频 二次调频 协同运行策略
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考虑用户意愿下电动汽车动态参与调频服务的两阶段优化调度 被引量:1
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作者 刘可真 赵贞焰 +4 位作者 何界东 赵现平 陈艳霞 陈明 谭化平 《电网技术》 北大核心 2025年第5期1859-1868,I0030-I0035,共16页
为应对新型电力系统中现有调频资源调频能力不足、灵活性不够的问题,亟需挖掘灵活的调频资源。规模化的电动汽车同时具备调频资源所需的灵活性和快速性,但其出力具有强不确定性。针对上述问题,提出了考虑用户意愿下大规模电动汽车(elect... 为应对新型电力系统中现有调频资源调频能力不足、灵活性不够的问题,亟需挖掘灵活的调频资源。规模化的电动汽车同时具备调频资源所需的灵活性和快速性,但其出力具有强不确定性。针对上述问题,提出了考虑用户意愿下大规模电动汽车(electric vehicle,EV)集群动态参与调频服务的两阶段优化调度策略。首先,基于用户意愿数据和蛇优化下的支持向量机-随机森林算法构建用户意愿分类预测模型。进一步,综合用户意愿和调频能力,对电动汽车划分集群,并建立集群动态调频出力模型,对调频集群的调频潜力进行评估。然后,提出了以剩余调频功率需求波动性最小为目标的日前-日内两阶段优化调度模型,在日前阶段求解全局最优调度计划,而在日内阶段采用滚动优化方法对调度计划进行局部优化和修正。最后,在现有调频市场结算方式下提出停车费分摊策略,并对调频参与者进行收益评估。通过仿真算例验证所提调度策略能够提高电动汽车聚合商调度下的电动汽车集群参与调频服务的可控性,并提高了电动汽车聚合商和用户的经济性。 展开更多
关键词 电动汽车集群 用户意愿 动态调频出力 滚动优化 停车费分摊策略
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自然降雨驱动的光伏组件清洁周期动态更新策略研究
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作者 刘卫东 吴锦华 +1 位作者 胡珊 闻海浪 《太阳能学报》 北大核心 2025年第1期615-623,共9页
提出一种考虑自然降雨对灰尘沉积的清洁效果及其对发电量影响的光伏组件清洁周期的动态分析设计方法。该方法采用关联图法和相关性分析确定影响光伏组件清洁及发电量的主要因素,以此为基础建立降雨量和灰尘沉积的定量关系和考虑灰尘沉... 提出一种考虑自然降雨对灰尘沉积的清洁效果及其对发电量影响的光伏组件清洁周期的动态分析设计方法。该方法采用关联图法和相关性分析确定影响光伏组件清洁及发电量的主要因素,以此为基础建立降雨量和灰尘沉积的定量关系和考虑灰尘沉积影响的发电量预测模型,再将其应用于动态更新或调整清洁周期。所提出方法应用于浙江省杭州市某光伏电站清洁策略的制定,结果表明清洁周期动态更新策略下的清洁总成本相较于不清洁时降低20.04%,相较于固定清洁周期方法降低3.63%。 展开更多
关键词 光伏组件 灰尘 降雨 发电量预测 清洁策略
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级联H桥逆变器的新型功率均衡调制策略
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作者 顾军 张维国 +2 位作者 李平 张明 杜治斌 《电源学报》 北大核心 2025年第5期42-50,共9页
针对级联H桥逆变器在传统的同相层叠PD(phase disposition)调制策略下,各单元之间存在功率不均衡问题,深入分析自由度控制原理,提出1种新型功率均衡调制策略,在保证输出功率均衡和电压谐波特性的基础上,缩短功率均衡时间,降低数字控制... 针对级联H桥逆变器在传统的同相层叠PD(phase disposition)调制策略下,各单元之间存在功率不均衡问题,深入分析自由度控制原理,提出1种新型功率均衡调制策略,在保证输出功率均衡和电压谐波特性的基础上,缩短功率均衡时间,降低数字控制复杂度。该方法一方面在PD调制法的基础上对三角载波进行自由度重组,让其均匀分布于不同载波层间,充分利用各输出电平的开关冗余状态,使其在1个载波周期内实现功率均衡来缩短均衡所需时间;另一方面,对调制波垂直自由度进行重组,以降低数字控制的复杂度。最后通过仿真和实验对理论分析及可行性进行验证。 展开更多
关键词 级联H桥 调制策略 功率均衡 自由度 功率均衡时间
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模块化多电平换流器谐波特性分析与建模
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作者 田震 徐遐龄 +3 位作者 肖大军 刘思杰 李鑫 孙建军 《武汉大学学报(工学版)》 北大核心 2025年第8期1304-1314,共11页
充分考虑调制策略、死区时间和控制策略等影响因素,建立了模块化多电平换流器(modular multilevel converter,MMC)的完整谐波源模型。首先,根据经典的谐波建模方法,提出了包含谐波电压源和谐波阻抗的MMC等效谐波源电路模型;然后,分析调... 充分考虑调制策略、死区时间和控制策略等影响因素,建立了模块化多电平换流器(modular multilevel converter,MMC)的完整谐波源模型。首先,根据经典的谐波建模方法,提出了包含谐波电压源和谐波阻抗的MMC等效谐波源电路模型;然后,分析调制策略、死区时间对MMC输出谐波的影响机理,建立调制策略、死区时间影响下MMC的谐波电压模型;进一步,考虑锁相环、环流抑制、电流内环、功率外环等典型控制环节的影响,基于多谐波线性化方法建立MMC的宽频阻抗模型;最后,利用MATLAB/Simulink对所建MMC谐波源模型进行仿真验证。分析结果表明,功率因数、输出功率和死区时间对基于MMC的柔性直流输电系统的谐波电流有显著影响。 展开更多
关键词 模块化多电平换流器 谐波源模型 调制策略 死区时间 多谐波线性化 阻抗模型
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新型无输入电解电容的电源适配器拓扑与控制策略研究
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作者 陈庆彬 张翔锃 +2 位作者 陈耀东 汪金帅 陈为 《天津大学学报(自然科学与工程技术版)》 北大核心 2025年第8期874-884,共11页
随着科学技术的发展,功率密度已经成为带有功率传输(PD)协议的电源适配器中十分关键的技术指标之一.在传统PD电源适配器中输入电解电容的体积占比突出,为了进一步提高其功率密度,提出了一种无输入电解电容的PD电源适配器电路.该电路拓... 随着科学技术的发展,功率密度已经成为带有功率传输(PD)协议的电源适配器中十分关键的技术指标之一.在传统PD电源适配器中输入电解电容的体积占比突出,为了进一步提高其功率密度,提出了一种无输入电解电容的PD电源适配器电路.该电路拓扑在传统反激变换器的基础上,除去了体积占比较大的输入电解电容,并引入由储能电路与Buck电路所组成的能量补偿模块,平衡输入与输出之间的脉动功率,从而有效抑制输出电压纹波.本文详细分析了所提出的电路拓扑结构及工作原理,在此基础上采用了适合该拓扑结构的基于前馈形式的单周期控制,并提出辅以功率平衡控制以及输出恒压控制的综合控制策略,同时对电路的关键参数进行设计.最后搭建了一个40W的PD电源适配器实验平台验证该方案的正确性和可行性.实验结果表明,该电路方案将输出电压纹波降低到了2%以下,并消除了输入电解电容,从而有效提高了PD电源适配器的功率密度. 展开更多
关键词 PD电源适配器 无输入电解电容 能量补偿模块 综合控制策略 高功率密度
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基于深度学习网络的OFDM信号识别方法研究
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作者 熊刚 刘涛 耿亮 《舰船电子对抗》 2025年第3期93-97,共5页
由于当今通信网络技术的蓬勃发展,电磁空间环境也更加错综复杂。针对复杂电磁环境中的正交频分复用(OFDM)信号识别问题,提出了一种基于深度学习网络——卷积神经网络(CNN)的识别方法,通过对卷积网络结构以及分类模型参数设计的优化,使... 由于当今通信网络技术的蓬勃发展,电磁空间环境也更加错综复杂。针对复杂电磁环境中的正交频分复用(OFDM)信号识别问题,提出了一种基于深度学习网络——卷积神经网络(CNN)的识别方法,通过对卷积网络结构以及分类模型参数设计的优化,使得算法具有良好的抗噪性与识别准确率。仿真结果表明新方法的识别性能较佳,在低信噪比情况下比过去一些传统的算法具有更好的识别性能,为OFDM信号的识别提供了参考。 展开更多
关键词 正交频分复用信号 卷积神经网络 调制识别 Dropout策略
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