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Calcium-sensitive protein MLC1 as a possible modulator of the astrocyte functional state
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作者 Elena Ambrosini Angela Lanciotti Maria Stefania Brignone 《Neural Regeneration Research》 SCIE CAS 2025年第7期2008-2010,共3页
Astrocytes,the main population of glial cells in the central nervous system(CNS),exert essential tasks for the control of brain tissue homeostasis,supporting neuron and other glial cell activity from the developmental... Astrocytes,the main population of glial cells in the central nervous system(CNS),exert essential tasks for the control of brain tissue homeostasis,supporting neuron and other glial cell activity from the developmental stage to adult life.To maintain the optimal functionality of the brain,astroglial cells are particularly committed to reacting to every change in tissue homeostatic conditions,from mild modifications of the physiological environment,a process called astrocyte activation,to the more severe alterations occurring in pathological situations causing astrocyte reactivity or reactive astrogliosis(Escartin et al.,2021).During these reactive states,astrocytes mount an active,progressive response encompassing morphological,molecular,and interactional remodeling,leading to the acquisition of new functions and the loss of others,whose intensity,duration,and reversibility are dependent on the nature of the stimulus and regulated in a context-specific manner. 展开更多
关键词 alterations modulator MAINTAIN
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Neuropeptide cholecystokinin:a key neuromodulator for hippocampal functions
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作者 Fengwen Huang Stephen Temitayo Bello 《Neural Regeneration Research》 SCIE CAS 2025年第7期1991-1992,共2页
Spatial memory is crucial for survival within external surroundings and wild environments.The hippocampus,a critical hub for spatial learning and memory formation,has received extensive investigations on how neuromodu... Spatial memory is crucial for survival within external surroundings and wild environments.The hippocampus,a critical hub for spatial learning and memory formation,has received extensive investigations on how neuromodulators shape its functions(Teixeira et al.,2018;Zhang et al.,2024).However,the landscape of neuromodulations in the hippocampal system remains poorly understood because most studies focus on classical monoamine neuromodulators,such as acetylcholine,serotonin,dopamine,and noradrenaline.The neuropeptides,comprising the most abundant neuromodulators in the central nervous system,play a pivotal role in neural information processing in the hippocampal system.Cholecystokinin(CCK),one of the most abundant neuropeptides,has been implicated in regulating various physiological and neurobiological statuses(Chen et al.,2019).CCK-A receptor(CCK-AR)and CCK-B receptors(CCK-BR)are two key receptors mediating the biological functions of CCK,both of which belong to class-A sevenfold transmembrane G protein-coupled receptors(Nishimura et al.,2015).CCK-AR preferentially reacts to sulfated CCK,whereas CCK-BR binds both CCK and gastrin with similar affinities(Ding et al.,2022).The expression patterns of CCK-AR and CCK-BR are distinct,implying that CCK has various functions in target regions.For instance,CCK-AR is widely expressed in the GI and brain subregions and is hence implicated in the control of digestive function and satiety regulation.Conversely,CCK-BR is abundantly and widely distributed in the central nervous system,which majorly regulates anxiety,learning,and memory(Ding et al.,2022).However,the roles of endogenous CCK and CCK receptors in regulating hippocampal function at electrophysiological and behavioral levels have received less attention. 展开更多
关键词 abundant FUNCTIONS modulator
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兼顾共模电压抑制与中性点电压平衡的T型三电平逆变器DPWM策略 被引量:1
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作者 叶少茜 张希 朱翀 《电源学报》 CSCD 北大核心 2024年第5期133-142,共10页
为提升T型三电平逆变器的可靠性与效率,提出1种可抑制共模电压的非连续脉宽调制RCVDPWM(reduced-common-mode-voltage pulse width modulation)策略,同时能够降低开关损耗。根据T型三电平拓扑开关序列对共模电压作用机理,总结出5种实现... 为提升T型三电平逆变器的可靠性与效率,提出1种可抑制共模电压的非连续脉宽调制RCVDPWM(reduced-common-mode-voltage pulse width modulation)策略,同时能够降低开关损耗。根据T型三电平拓扑开关序列对共模电压作用机理,总结出5种实现共模电压抑制的非连续脉宽调制DPWM(discontinuous pulse width modulation)钳位方式。分析表明,在任意调制度和相角下,至少存在1种实现共模电压抑制的钳位方式。对于部分相角区间存在的多种钳位方式,优先选取电流绝对值最大相的开关管进行钳位,以降低开关损耗。同时,所提RCVDPWM策略可保证中性点电压直流分量为0,具有中性点自平衡能力。实验结果验证了RCVDPWM策略的可行性与有效性。 展开更多
关键词 非连续脉宽调制 开关损耗 共模电压 中性点
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Influence of substrate effect on near-field radiative modulator based on biaxial hyperbolic materials
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作者 刘睿一 刘皓佗 +2 位作者 胡杨 崔峥 吴小虎 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期56-64,共9页
Relative rotation between the emitter and receiver could effectively modulate the near-field radiative heat transfer(NFRHT)in anisotropic media.Due to the strong in-plane anisotropy,natural hyperbolic materials can be... Relative rotation between the emitter and receiver could effectively modulate the near-field radiative heat transfer(NFRHT)in anisotropic media.Due to the strong in-plane anisotropy,natural hyperbolic materials can be used to construct near-field radiative modulators with excellent modulation effects.However,in practical applications,natural hyperbolic materials need to be deposited on the substrate,and the influence of substrate on modulation effect has not been studied yet.In this work,we investigate the influence of substrate effect on near-field radiative modulator based onα-MoO_(3).The results show that compared to the situation without a substrate,the presence of both lossless and lossy substrate will reduce the modulation contrast(MC)for different film thicknesses.When the real or imaginary component of the substrate permittivity increases,the mismatch of hyperbolic phonon polaritons(HPPs)weakens,resulting in a reduction in MC.By reducing the real and imaginary components of substrate permittivity,the MC can be significantly improved,reaching 4.64 forε_(s)=3 at t=10 nm.This work indicates that choosing a substrate with a smaller permittivity helps to achieve a better modulation effect,and provides guidance for the application of natural hyperbolic materials in the near-field radiative modulator. 展开更多
关键词 near-field radiative modulator substrate effect hyperbolic material modulation contrast
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Exploring the modulatory role of bovine lactoferrin on the microbiome and the immune response in healthy and Shiga toxin‑producing E.coli challenged weaned piglets
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作者 Matthias Dierick Ruben Ongena +2 位作者 Daisy Vanrompay Bert Devriendt Eric Cox 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第3期1278-1291,共14页
Background Post-weaned piglets suffer from F18+Escherichia coli(E.coli)infections resulting in post-weaning diar-rhoea or oedema disease.Frequently used management strategies,including colistin and zinc oxide,have con... Background Post-weaned piglets suffer from F18+Escherichia coli(E.coli)infections resulting in post-weaning diar-rhoea or oedema disease.Frequently used management strategies,including colistin and zinc oxide,have contrib-uted to the emergence and spread of antimicrobial resistance.Novel antimicrobials capable of directly interacting with pathogens and modulating the host immune responses are being investigated.Lactoferrin has shown promising results against porcine enterotoxigenic E.coli strains,both in vitro and in vivo.Results We investigated the influence of bovine lactoferrin(bLF)on the microbiome of healthy and infected weaned piglets.Additionally,we assessed whether bLF influenced the immune responses upon Shiga toxin-producing E.coli(STEC)infection.Therefore,2 in vivo trials were conducted:a microbiome trial and a challenge infection trial,using an F18+STEC strain.BLF did not affect theα-andβ-diversity.However,bLF groups showed a higher relative abundance(RA)for the Actinobacteria phylum and the Bifidobacterium genus in the ileal mucosa.When analysing the immune response upon infection,the STEC group exhibited a significant increase in F18-specific IgG serum levels,whereas this response was absent in the bLF group.Conclusion Taken together,the oral administration of bLF did not have a notable impact on theα-andβ-diversity of the gut microbiome in weaned piglets.Nevertheless,it did increase the RA of the Actinobacteria phylum and Bifi-dobacterium genus,which have previously been shown to play an important role in maintaining gut homeostasis.Furthermore,bLF administration during STEC infection resulted in the absence of F18-specific serum IgG responses. 展开更多
关键词 E.COLI Immune modulation LACTOFERRIN MICROBIOME
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Light-field modulation and optimization near metal nanostructures utilizing spatial light modulators
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作者 Zini Cao Hai Lin +3 位作者 Yuqing Cheng Yixuan Xu Qihuang Gong Guowei Lü 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第10期1-14,共14页
Plasmonic modes within metal nanostructures play a pivotal role in various nanophotonic applications.However,a significant challenge arises from the fixed shapes of nanostructures post-fabrication,resulting in limited... Plasmonic modes within metal nanostructures play a pivotal role in various nanophotonic applications.However,a significant challenge arises from the fixed shapes of nanostructures post-fabrication,resulting in limited modes under ordinary illumination.A promising solution lies in far-field control facilitated by spatial light modulators(SLMs),which enable on-site,real-time,and non-destructive manipulation of plasmon excitation.Through the robust modulation of the incident light using SLMs,this approach enables the generation,optimization,and dynamic control of surface plasmon polariton(SPP)and localized surface plasmon(LSP)modes.The versatility of this technique introduces a rich array of tunable degrees of freedom to plasmon-enhanced spectroscopy,offering novel approaches for signal optimization and functional expansion in this field.This paper provides a comprehensive review of the generation and modulation of SPP and LSP modes through far-field control with SLMs and highlights the diverse applications of this optical technology in plasmon-enhanced spectroscopy. 展开更多
关键词 surface plasmon spatial light modulator dynamic control plasmon-enhanced spectroscopy
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Identification of FDA-Approved Drugs as Modulators of Multidrug Resistance Protein 2 (MRP2/ABCC2) Expression Levels in MRP2-Overexpressing Cells: Preliminary Data
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作者 Vivian Osei Poku Surtaj Hussain Iram 《Journal of Biosciences and Medicines》 2024年第10期32-44,共13页
Multidrug Resistance Protein 2 (MRP2) is an ATP-dependent transmembrane protein that plays a pivotal role in the efflux of a wide variety of physiological substrates across the plasma membrane. Several studies have sh... Multidrug Resistance Protein 2 (MRP2) is an ATP-dependent transmembrane protein that plays a pivotal role in the efflux of a wide variety of physiological substrates across the plasma membrane. Several studies have shown that MRP2 can significantly affect the absorption, distribution, metabolism, excretion, and toxicity (ADMET) profiles of many therapeutic drugs and chemicals found in the environment and diet. This transporter can also efflux newly developed anticancer agents that target specific signaling pathways and are major clinical markers associated with multidrug resistance (MDR) of several types of cancers. MDR remains a major limitation to the advancement of the combinatorial chemotherapy regimen in cancer treatment. In addition to anticancer agents, MRP2 reduces the efficacy of various drug classes such as antivirals, antimalarials, and antibiotics. The unique role of MRP2 and its contribution to MDR makes it essential to profile drug-transporter interactions for all new and promising drugs. Thus, this current research seeks to identify modulators of MRP2 protein expression levels using cell-based assays. A unique recently approved FDA library (372 drugs) was screened using a high-throughput In-Cell ELISA assay to determine the effect of these therapeutic agents on protein expression levels of MRP2. A total of 49 FDA drugs altered MRP2 protein expression levels by more than 50% representing 13.17% of the compounds screened. Among the identified hits, thirty-nine (39) drugs increased protein expression levels whereas 10 drugs lowered protein expression levels of MRP2 after drug treatment. Our findings from this initial drug screening showed that modulators of MRP2 peregrinate multiple drug families and signify the importance of profiling drug interactions with this transporter. Data from this study provides essential information to improve combinatorial drug therapy and precision medicine as well as reduce the drug toxicity of various cancer chemotherapies. 展开更多
关键词 ABC Transporters Multidrug Resistance MRP2/ABCC2 MRP2 modulators ELISA
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A high-contrast imaging coronagraph for segmented-mirror large aperture telescopes using a spatial light modulator
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作者 Jiangpei Dou Huanyu Dong 《Astronomical Techniques and Instruments》 CSCD 2024年第3期166-170,共5页
The primary mirrors of current and future large telescopes always employ a segmented mirror configuration.The small but non-negligible gaps between neighboring segments cause additional diffraction,which restricts the... The primary mirrors of current and future large telescopes always employ a segmented mirror configuration.The small but non-negligible gaps between neighboring segments cause additional diffraction,which restricts the performance of high-contrast coronagraph.To solve this problem,we propose a coronagraph system based on a single liquid crystal spatial light modulator(SLM).This spatial light modulator is used for amplitude apodization,and its feasibility and potential performance are demonstrated using a laboratory setup using the stochastic parallel gradient descent(SPGD)algorithm to control the spatial light modulator,which is based on point spread function(PSF)sensing and evaluation and optimized for maximum contrast in the discovery working area as a merit function.The system delivers a contrast in the order of 10−6,and shows excellent potential to be used in current and future large aperture telescopes,both on the ground and in space. 展开更多
关键词 Liquid crystal spatial light modulator Amplitude apodized pupil Large aperture telescopes
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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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HD-YOLO:复杂场景下安全帽佩戴检测算法
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作者 邱云飞 腰瑞琳 +1 位作者 金海波 张嘉宁 《安全与环境学报》 北大核心 2025年第1期165-174,共10页
针对目标密集、有遮挡的复杂施工场景下安全帽佩戴检测存在漏检、误检的问题,提出了一种基于YOLOv8的HD-YOLO安全帽佩戴检测算法。首先,设计了GRC-C2f结构,使用多分支结构捕获多尺度特征,兼顾训练阶段的特征提取能力和推理阶段的计算效... 针对目标密集、有遮挡的复杂施工场景下安全帽佩戴检测存在漏检、误检的问题,提出了一种基于YOLOv8的HD-YOLO安全帽佩戴检测算法。首先,设计了GRC-C2f结构,使用多分支结构捕获多尺度特征,兼顾训练阶段的特征提取能力和推理阶段的计算效率。其次,设计了DSASF颈部结构,结合动态上采样和多尺度特征融合,精准识别和定位图像中的小目标,以提高检测性能。然后,引入Focal Modulation模块替换原有的快速空间金字塔池化(Spatial Pyramid Pooling-Fast,SPPF)结构模块,捕捉图像中的长距离依赖和上下文信息,聚焦于复杂背景中的目标。最后,采用空间增强注意力模块(Spatially Enhanced Attention Module,SEAM)解决小目标遮挡问题。试验结果表明,HD-YOLO算法在同一数据集上平均精度均值为81.8%,相比原始YOLOv8算法提高了5.0百分点。设计的HD-YOLO算法有效提高了复杂场景中佩戴安全帽的检测精度。 展开更多
关键词 安全社会工程 安全帽检测 YOLOv8算法 GRC-C2f模块 DSASF颈部结构 Focal Modulation模块 空间增强注意力模块
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机场智慧飞行区愿景与架构
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作者 刘诗福 赵鸿铎 +1 位作者 郝航程 凌建明 《同济大学学报(自然科学版)》 北大核心 2025年第1期75-82,共8页
针对目前机场飞行区运行现状及管理使用的需求,结合《智慧民航建设路线图》和未来科技发展趋势,明确了机场智慧飞行区运行愿景。在此基础上,进一步诠释与梳理智慧飞行区的架构。智慧飞行区以智能物理要素为基础,以功能系统为支撑,组织... 针对目前机场飞行区运行现状及管理使用的需求,结合《智慧民航建设路线图》和未来科技发展趋势,明确了机场智慧飞行区运行愿景。在此基础上,进一步诠释与梳理智慧飞行区的架构。智慧飞行区以智能物理要素为基础,以功能系统为支撑,组织相关业务模块,最终保障运行愿景的实现。最后,系统分析了智慧飞行区在场面运行、设施管养、地勤服务、应急救援、能源保障方面的发展方向,提出了有效支撑智慧飞行区安全、效率、效益、环保的业务组织模式,对未来智慧飞行区的规划与应用具有重要参考意义和价值。 展开更多
关键词 智慧飞行区 愿景 架构 功能系统 业务模块
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基于半桥三电平LLC谐振变换器的混合控制策略研究
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作者 王君瑞 赵东琦 +1 位作者 陈剑飞 秦豪 《现代电子技术》 北大核心 2025年第2期1-8,共8页
半桥三电平LLC谐振变换器具有体积小、开关器件少、开关器件耐压高等优势,已逐渐应用于直流充电模块后级为动力电池充电。针对传统变频调制(PFM)策略与移相调制(PSM)策略无法实现宽输出电压范围的问题进行分析,提出一种宽增益范围的移相... 半桥三电平LLC谐振变换器具有体积小、开关器件少、开关器件耐压高等优势,已逐渐应用于直流充电模块后级为动力电池充电。针对传统变频调制(PFM)策略与移相调制(PSM)策略无法实现宽输出电压范围的问题进行分析,提出一种宽增益范围的移相-变频(PSM-PFM)混合控制策略。通过搭建一台功率为600 W、输出电压为20~60 V的实验样机进行验证。实验结果表明,所提控制策略相比单一调制策略具有更宽的增益,进而可实现宽输出电压范围,能够为动力电池提供稳定、宽范围且可调的充电电压,并实现开关管零电压开通。 展开更多
关键词 LLC谐振变换器 变频调制 移相调制 混合控制 零电压开关 宽输出电压
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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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光-储电站参与多应用场景的日前-日内协同滚动优化策略
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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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无人机应用专业虚拟实训平台建设与应用研究
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作者 高琼 韩清清 +1 位作者 杜文志 贾洪涛 《黄河水利职业技术学院学报》 2025年第1期61-65,共5页
在数字教育视域下,无人机应用专业虚拟实训平台的建设与应用研究是当前教育领域的重要课题。结合教学实践,针对无人机应用专业在实训教学过程中的“三高三难”痛点、难点问题,利用计算机技术和强大的工业软件系统构建了虚拟实训平台,形... 在数字教育视域下,无人机应用专业虚拟实训平台的建设与应用研究是当前教育领域的重要课题。结合教学实践,针对无人机应用专业在实训教学过程中的“三高三难”痛点、难点问题,利用计算机技术和强大的工业软件系统构建了虚拟实训平台,形成了提升无人机应用专业教育质量和效果的创新教学模式。实践表明,这一创新教学模式能够有效提升学生的实践能力和创新意识,提升教学效果,可为数字教育背景下无人机应用专业教育的发展提供有益借鉴。 展开更多
关键词 数字教育 无人机应用专业 虚拟实训平台 无人机设备认知模块 无人机航线规划仿真模块 无人机高分辨率对地观测模块 无人机摄影测量仿真模块
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利用匹配滤波的调频连续波激光测距技术研究
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作者 张鹏 封治华 +5 位作者 张鹏飞 赵渊明 阮友田 韩文杰 张辉 康朝阳 《激光技术》 北大核心 2025年第1期53-61,共9页
基于差频解算的调频连续波激光测距技术存在测量距离短、易受噪声干扰、受非线性调频影响大的问题。为了在相同机制条件下解决此问题,提出了基于匹配滤波的调频连续波激光测距方法,改进相干探测光路,加入信号反转单元和信号共轭单元,将... 基于差频解算的调频连续波激光测距技术存在测量距离短、易受噪声干扰、受非线性调频影响大的问题。为了在相同机制条件下解决此问题,提出了基于匹配滤波的调频连续波激光测距方法,改进相干探测光路,加入信号反转单元和信号共轭单元,将混频器换成卷积器,同时满足系统响应与发射波形匹配,并进行了相关仿真实验。结果表明,相比差频解算方法,匹配滤波方法可实现两倍于差频解算方法的测距范围,信噪比提高了9.5 dB,在非线性调频误差为19.8 MHz、198 MHz和396 MHz条件下均能得到较高分辨率的距离谱,表现出较好的抵抗非线性调频的能力。此研究可为该领域的科研工作者提供技术指导和新的思路。 展开更多
关键词 激光技术 调频连续波 匹配滤波 激光测距 信噪比 非线性
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基于改进LSTM的数码雷管模组印刷质量预测
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作者 许可 高宏宇 +1 位作者 宫华 孙文娟 《沈阳理工大学学报》 CAS 2025年第1期9-18,24,共11页
由于数码雷管模组印刷过程中生产工艺复杂、强时序性等特点,其质量的精准预测已成为提高产品质量管理水平的关键。基于此提出一种改进长短期记忆(long short-term memory,LSTM)网络的数码雷管模组印刷质量预测模型。首先根据数码雷管模... 由于数码雷管模组印刷过程中生产工艺复杂、强时序性等特点,其质量的精准预测已成为提高产品质量管理水平的关键。基于此提出一种改进长短期记忆(long short-term memory,LSTM)网络的数码雷管模组印刷质量预测模型。首先根据数码雷管模组印刷过程提炼机器运行参数、环境参数与检测参数作为印刷产品质量的原始特征,并对关键检测参数进行时序特征重构以增强特征表达能力;其次基于改进的LSTM网络建立数码雷管模组印刷特征提取框架,采用卷积神经网络提取空间特征避免LSTM挖掘高维印刷特征时隐含关系的不足,通过全局注意力机制自适应学习不同时刻印刷特征对印刷产品质量的贡献度,为LSTM提取的深层时序特征分配不同权值;最后以深层特征作为输入,通过全连接网络实现数码雷管模组印刷产品的质量预测。实验结果表明,相较于BP神经网络、门控循环单元网络、LSTM等预测方法,改进的LSTM网络有效提高了数码雷管模组印刷产品质量的预测精度。 展开更多
关键词 模组印刷 质量预测 长短期记忆网络 特征重构
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自旋-轨道耦合作用下极化激元凝聚中的调制不稳定性
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作者 陈海军 《原子与分子物理学报》 CAS 北大核心 2025年第6期136-143,共8页
利用线性稳定性分析方法,对存在自旋-轨道耦合(SOS)作用的二维极化激元玻色-爱因斯坦凝聚(BEC)系统中的调制不稳定性(MI)进行了研究.分析了组分内部,组分之间以及SOC相互作用对系统调制不稳定性的影响.结果显示,当系统内部不存在SOC作用... 利用线性稳定性分析方法,对存在自旋-轨道耦合(SOS)作用的二维极化激元玻色-爱因斯坦凝聚(BEC)系统中的调制不稳定性(MI)进行了研究.分析了组分内部,组分之间以及SOC相互作用对系统调制不稳定性的影响.结果显示,当系统内部不存在SOC作用,组分之间的相互作用为0,组分内部存在排斥作用时,不会出现调制不稳定性,组分内部存在吸引作用时,会出现调制不稳定性,并且调制不稳定性区间长度随吸引作用的增强而增加;组分之间相互作用不为0时,组分之间的相互作用以平方形式出现,其正负不会对调制不稳定性产生实质性影响.存在SOC相互作用时,SOC相互作用会引起增益谱曲线的不规则振荡,破坏原来的调制不稳定性区间. 展开更多
关键词 极化激元凝聚 调制不稳定性 自旋-轨道耦合 双分量
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多叠加导频OTFS系统低峰均比信道估计
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作者 何继爱 刘涛 +1 位作者 王乐 王婵飞 《电讯技术》 北大核心 2025年第1期81-88,共8页
针对现有信道估计方案导致正交时频空间(Orthogonal Time Frequency Space,OTFS)调制系统峰均功率比(Peak-to-Average Power Ratio,PAPR)高或频谱效率(Spectral Efficiency,SE)低的问题,提出一种多叠加导频的低PAPR、高SE信道估计方法... 针对现有信道估计方案导致正交时频空间(Orthogonal Time Frequency Space,OTFS)调制系统峰均功率比(Peak-to-Average Power Ratio,PAPR)高或频谱效率(Spectral Efficiency,SE)低的问题,提出一种多叠加导频的低PAPR、高SE信道估计方法。发送端利用时域正交性和离散傅里叶域相位的随机性,在时延多普勒域中嵌入与数据相叠加的5导频符号的导频图案实现低PAPR,提高SE。接收端以数据符号与噪声之和的能量均值为基准,实现导频信号检测,同时根据每个导频的不同位置信息恢复出存在相位旋转的数据信号。基于能量准则,利用多个独立的接收信号进行联合信道估计,以降低数据符号的干扰,并采用消息传递算法进行数据恢复。仿真结果表明,该方法比单叠加导频信道估计的PAPR低,同时较嵌入式导频信道估计的SE提高约14.4%。 展开更多
关键词 正交时频空间(OTFS)调制 信道估计 时延多普勒域 多叠加导频
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面向复杂背景下烟雾火焰检测的改进YOLOv8s算法
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作者 马耀名 张鹏飞 谭福生 《计算机工程与应用》 北大核心 2025年第3期121-130,共10页
针对复杂背景下烟雾火焰目标与背景混淆,导致烟雾火焰检测精度低等问题,提出一种面向复杂背景下烟雾火焰检测的YOLOv8s改进模型。特征通道之间具有高度相似性,为了有效利用跨不同通道间的冗余,提高模型对烟雾火焰目标和背景的区分,设计... 针对复杂背景下烟雾火焰目标与背景混淆,导致烟雾火焰检测精度低等问题,提出一种面向复杂背景下烟雾火焰检测的YOLOv8s改进模型。特征通道之间具有高度相似性,为了有效利用跨不同通道间的冗余,提高模型对烟雾火焰目标和背景的区分,设计了C2fFR(C2f with partial rep conv)轻量级特征提取模块。设计了MCFM(multi-scale context fusion module)多尺度上下文融合模块,来捕捉并利用上下文信息,增强特征的表示。使用Inner-SIoU损失函数,解决边界框不匹配的问题,提高模型对高IoU样本的回归能力。实验结果表明,改进后的YOLOv8s烟雾火焰检测模型相比于基线模型YOLOv8s,mAP@50提升了4.6个百分点,mAP@50:95提升了2.3个百分点,模型参数量降低了18.9%,计算量降低了8.1%,FPS为93帧/s,与其他主流检测算法相比也具有较好的检测性能。 展开更多
关键词 YOLOv8s C2fFR 多尺度上下文融合 Inner-SIoU
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