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基于DMD方法的结冰对翼型绕流流场低阶模态的影响研究
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作者 吴雪飞 刘勇 +1 位作者 邹宇 胡佳伟 《郑州航空工业管理学院学报》 2025年第1期26-33,共8页
基于大涡模拟(Large Eddy Simulation,LES)方法,对NACA0012翼型在结冰和未结冰两种工况下进行了数值模拟,同时基于动力学模态分解(Dynamic modal decomposition,DMD)方法分析了结冰对翼型非定常流动低阶模态的影响。结果表明,7.5°... 基于大涡模拟(Large Eddy Simulation,LES)方法,对NACA0012翼型在结冰和未结冰两种工况下进行了数值模拟,同时基于动力学模态分解(Dynamic modal decomposition,DMD)方法分析了结冰对翼型非定常流动低阶模态的影响。结果表明,7.5°迎角时,结冰对翼型升力系数幅值的影响较大,随着迎角的增大,结冰对升力系数幅值的影响开始减弱;尤其是在13.5°迎角时,结冰与迎角产生了耦合作用,加强了对升力系数幅值的影响。通过DMD分析发现,在低阶模态下,干净翼型大尺度流动结构在7.5°迎角下具有周期性演变的特性,结冰翼型的大尺度流动结构在13.5°迎角时出现了上述特征;此外还发现,随着迎角增加,干净翼型大尺度流动结构波长变长,而结冰翼型其波长变短,但两种翼型大尺度流动结构所对应的频率都明显降低。 展开更多
关键词 结冰 dmd 流动分离 模态分析
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基于DMD的阿达玛变换型近红外光谱仪快速处理系统设计与实现 被引量:1
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作者 王硕 谢振坤 魏志鹏 《光谱学与光谱分析》 SCIE EI CAS 北大核心 2025年第1期133-138,共6页
数字微镜器件(DMD)的近红外光谱仪,具有波长重复性好、分辨率高和抗振动性好等优点,广泛应用于食品安全和农业生产等领域的研究。随着DMD的微小型近红外光谱仪发展逐渐趋于成熟,仪器的成本和性能仍然是研发的关键。尽管大部分将重点放... 数字微镜器件(DMD)的近红外光谱仪,具有波长重复性好、分辨率高和抗振动性好等优点,广泛应用于食品安全和农业生产等领域的研究。随着DMD的微小型近红外光谱仪发展逐渐趋于成熟,仪器的成本和性能仍然是研发的关键。尽管大部分将重点放在了软件开发和检测方法的研究,而仪器硬件的处理速度至关重要。只有确保光谱仪能够快速准确的采集并传输数据,才能有效实现光谱分析。在多数研究中,阿达玛矩阵的生成和解码工作通常由上位机完成,并通过FLASH存储的方式导入模板。这种方式可能会限制采集一幅完整光谱数据的时间效率。为了提高光谱采集速度和信噪比,提出一种高速驱动DMD和快速数据采集的方法,并基于DMD微小型近红外光谱仪设计一套硬件电路系统。采用现场可编辑门阵列(FPGA)和ARM的架构,创新性地实现了奇偶阿达玛模板的生成与解码过程在嵌入式系统底层执行,加快了光谱分析的速度并提高信噪比。通过与市面上DMD型光谱仪对比,研究结果显示,所研发的光谱仪完成单次光谱的采集时间仅需214 ms,相比商用DMD型光谱仪,采集效率提升了4倍。在同等3 s的采集时间内,所研发光谱仪的信噪比为4600,相比商用DMD型光谱仪,信噪比提升了1.5倍。通过所研发的光谱仪对油菜籽样品进行光谱扫描,分析了油菜籽的脂肪、蛋白质和水分的含量,并采用偏最小二乘回归(PLSR)建立了相应的模型。油菜籽脂肪含量的校正相关系数为0.9865、预测相关系数为0.9672;蛋白质含量的校正相关系数为0.9854、预测相关系数系数为0.9636;水分含量的校正相关系数为0.9875、预测相关系数为0.9614。模型评估的结果表明,该光谱仪能够满足油菜籽成分检测的需求,验证该光谱仪在商业领域具有重要的应用价值。 展开更多
关键词 数字微镜器件 近红外光谱仪 阿达玛 信噪比 嵌入式 油菜籽
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Recent Advances in Artificial Sensory Neurons:Biological Fundamentals,Devices,Applications,and Challenges
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作者 Shuai Zhong Lirou Su +4 位作者 Mingkun Xu Desmond Loke Bin Yu Yishu Zhang Rong Zhao 《Nano-Micro Letters》 SCIE EI CAS 2025年第3期168-216,共49页
Spike-based neural networks,which use spikes or action potentialsto represent information,have gained a lot of attention because of their high energyefficiency and low power consumption.To fully leverage its advantage... Spike-based neural networks,which use spikes or action potentialsto represent information,have gained a lot of attention because of their high energyefficiency and low power consumption.To fully leverage its advantages,convertingthe external analog signals to spikes is an essential prerequisite.Conventionalapproaches including analog-to-digital converters or ring oscillators,and sensorssuffer from high power and area costs.Recent efforts are devoted to constructingartificial sensory neurons based on emerging devices inspired by the biologicalsensory system.They can simultaneously perform sensing and spike conversion,overcoming the deficiencies of traditional sensory systems.This review summarizesand benchmarks the recent progress of artificial sensory neurons.It starts with thepresentation of various mechanisms of biological signal transduction,followed bythe systematic introduction of the emerging devices employed for artificial sensoryneurons.Furthermore,the implementations with different perceptual capabilitiesare briefly outlined and the key metrics and potential applications are also provided.Finally,we highlight the challenges and perspectives for the future development of artificial sensory neurons. 展开更多
关键词 Artificial intelligence Emerging devices Artificial sensory neurons Spiking neural networks Neuromorphic sensing
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Kali Pi—A Miniature Ultra-Portable Penetration Testing Device
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作者 Ahmed Bin Ali 《Journal of Information Security》 2025年第1期101-113,共13页
Penetration testing plays a critical role in ensuring security in an increasingly interconnected world. Despite advancements in technology leading to smaller, more portable devices, penetration testing remains reliant... Penetration testing plays a critical role in ensuring security in an increasingly interconnected world. Despite advancements in technology leading to smaller, more portable devices, penetration testing remains reliant on traditional laptops and computers, which, while portable, lack true ultra-portability. This paper explores the potential impact of developing a dedicated, ultra-portable, low-cost device for on-the-go penetration testing. Such a device could replicate the core functionalities of advanced penetration testing tools, including those found in Kali Linux, within a compact form factor that fits easily into a pocket. By offering the convenience and portability akin to a smartphone, this innovative device could redefine the way penetration testers operate, enabling them to carry essential tools wherever they go and ensuring they are always prepared to conduct security assessments efficiently. This approach aims to revolutionize penetration testing by merging high functionality with unparalleled portability. 展开更多
关键词 Penetration Testing Portable device CYBERSECURITY Raspberry Pi
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Preliminary Study on Irradiation Device of Fission Molybdenum-Technetium Production Based on China Advanced Research Reactor
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作者 Shi Shi Zhou Yidong 《Journal of Electronic Research and Application》 2025年第1期141-146,共6页
As a multipurpose research reactor,fission molybdenum-technetium irradiation production is one of the wide applications of China Advanced Research Reactor CARR.The goal of this study is to achieve“online loading and ... As a multipurpose research reactor,fission molybdenum-technetium irradiation production is one of the wide applications of China Advanced Research Reactor CARR.The goal of this study is to achieve“online loading and unloading”of the target during fission molybdenum-99(99Mo)to technetium-99m(99mTc)irradiation production without affecting the normal reactor operation and other irradiation channels,which will make CARR more efficient in performing irradiation tasks.This paper introduces the design principles,requirements and concept structural design of the irradiation device of fission 99Mo-99mTc. 展开更多
关键词 CARR Molybdenum-technetium production Irradiation device
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Performance Control and Application of ZnO-Based P-N Junction Piezoelectric Devices
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作者 Xudong Shen Dongying Liu Li Zhao 《Journal of Electronic Research and Application》 2025年第1期81-87,共7页
Zinc oxide(ZnO),as a broadband gap semiconductor material,exhibits unique physical and chemical properties that make it highly suitable for optoelectronics,piezoelectric devices,and gas-sensitive sensors,showing signi... Zinc oxide(ZnO),as a broadband gap semiconductor material,exhibits unique physical and chemical properties that make it highly suitable for optoelectronics,piezoelectric devices,and gas-sensitive sensors,showing significant potential for various applications.This paper focuses on the regulation and application of ZnO-based p-n junctions and piezoelectric devices.It discusses in detail the preparation of ZnO materials,the construction of p-n junctions,the optimization of piezoelectric device performance,and its application in various fields.By employing different preparation methods and strategies,high-quality ZnO thin films can be grown,and effective control of p-type conductivity achieved.This study provides both a theoretical foundation and technical support for controlling the performance of ZnO-based piezoelectric devices,as well as paving new pathways for the broader application of ZnO materials. 展开更多
关键词 ZNO p-n junction Piezoelectric device Performance control APPLICATION
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An Efficient and Flexible Bifunctional Dual-Band Electrochromic Device Integrating with Energy Storage
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作者 Zekun Huang Yutao Peng +7 位作者 Jing Zhao Shengliang Zhang Penglu Qi Xianlin Qu Fuqiang Yan Bing Ding Yimin Xuan Xiaogang Zhang 《Nano-Micro Letters》 2025年第4期419-434,共16页
Dual-band electrochromic devices capable of the spectral-selective modulation of visible(VIS)light and near-infrared(NIR)can notably reduce the energy consumption of buildings and improve the occupants’visual and the... Dual-band electrochromic devices capable of the spectral-selective modulation of visible(VIS)light and near-infrared(NIR)can notably reduce the energy consumption of buildings and improve the occupants’visual and thermal comfort.However,the low optical modulation and poor durability of these devices severely limit its practical applications.Herein,we demonstrate an efficient and flexible bifunctional dual-band electrochromic device which not only shows excellent spectral-selective electrochromic performance with a high optical modulation and a long cycle life,but also displays a high capacitance and a high energy recycling efficiency of 51.4%,integrating energy-saving with energy-storage.The nanowires structure and abundant oxygen-vacancies of oxygen-deficient tungsten oxide nanowires endows it high flexibility and a high optical modulation of 73.1%and 85.3%at 633 and 1200 nm respectively.The prototype device assembled can modulate the VIS light and NIR independently and effectively through three distinct modes with a long cycle life(3.3%capacity loss after 10,000 cycles)and a high energy-saving performance(8.8℃lower than the common glass).Furthermore,simulations also demonstrate that our device outperforms the commercial low-emissivity glass in terms of energy-saving in most climatic zones around the world.Such windows represent an intriguing potential technology to improve the building energy efficiency. 展开更多
关键词 Electrochromic Dual-band electrochromic devices Spectral-selective modulation FLEXIBLE Energy storage
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基于双DMD的红外场景投影仪的结构设计及有限元分析
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作者 李俊娜 高教波 +5 位作者 杨东来 胡煜 吴江辉 郑雅卫 袁良 孟合民 《仪器与设备》 2024年第3期354-361,共8页
红外场景投影仪能够模拟多种类型的目标与背景,对光电探测系统进行动态测试评估。为提高中波红外场景投影仪帧频速度和灰度等级,提出了一种基于双DMD (数字微反射器件)的设计方案。根据光学系统的特点及中波红外投影仪使用环境,对总体... 红外场景投影仪能够模拟多种类型的目标与背景,对光电探测系统进行动态测试评估。为提高中波红外场景投影仪帧频速度和灰度等级,提出了一种基于双DMD (数字微反射器件)的设计方案。根据光学系统的特点及中波红外投影仪使用环境,对总体结构进行选型。根据投影仪的使用环境要求,对其进行有限元分析,结论表明力学性能满足指标要求。投影仪的测试结果表明此系统完全满足指标要求。Infrared scene projector can simulate multiple types of targets and backgrounds, which can evaluate dynamic test of photoelectric detection systems. In order to improve the frame rate and the grey level of the midwave (MWIR) scene projector, the design scheme based on dual-DMD (Digital micro-mirror device) is presented. The overall structure is selected according to the characteristic of optical system and operational environment of the midwave (MWIR) scene projector. The finite element analysis of the system is carried out according to operating environment requirements, which results show that the mechanical properties meet the specification. The results of the testing for the projector illustrate that the performances of the optical systems meet the specifications of the infrared scene projector. 展开更多
关键词 动态测试 dmd (数字微反射器件) 结构设计 有限元分析
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一例DMD基因Alu元件插入突变导致杜氏肌营养不良及其白发症状分析
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作者 李慧 张如意 +3 位作者 李长叶 张肖林 郑庆印 刘秀珍 《遗传》 CAS CSCD 北大核心 2024年第7期570-580,共11页
杜氏肌营养不良(Duchenne muscular dystrophy,DMD)是由DMD基因突变引起的抗肌萎缩蛋白缺乏的一种严重X连锁隐性遗传病,突变形式主要包括外显子缺失和重复、点突变、插入突变等,这些突变通过不同方式影响了抗肌萎缩蛋白的正常表达,最终... 杜氏肌营养不良(Duchenne muscular dystrophy,DMD)是由DMD基因突变引起的抗肌萎缩蛋白缺乏的一种严重X连锁隐性遗传病,突变形式主要包括外显子缺失和重复、点突变、插入突变等,这些突变通过不同方式影响了抗肌萎缩蛋白的正常表达,最终导致疾病的发生。本研究报告了1例DMD基因第59号外显子(exon 59,E59)插入突变引起的DMD,该患儿相关生化指标明显异常,表现较为明显的DMD早期症状,并出现了多处白发。其母亲和姐姐为携带者,生化指标轻微异常,母亲有轻微临床症状,姐姐无临床症状。其他成员基因和身体状况正常。经测序和序列比对发现,该插入片段为AluYa5亚家族的Alu元件,该片段插入可产生两个终止密码子,末端含一段多聚腺苷酸尾(polyA)。为了解该插入突变对于DMD基因的影响以及与临床症状的关联,通过外显子剪接增强子(exonic splicing enhancer,ESE)预测发现,该插入并不影响E59的剪接,由此推测该插入序列会最终出现在DMD基因的mRNA序列中,插入序列中的2个终止子和polyA很可能会在翻译过程中发挥终止作用,不能产生有功能的抗肌萎缩蛋白,这可能是导致DMD发生的机制。另外该患儿除了典型的DMD症状外,还出现了过早白发症状。本研究首次报道了1例DMD基因编码区插入Alu元件导致的DMD,为研究Alu序列逆转座引发基因突变提供线索,同时扩展了对DMD基因突变的认识。 展开更多
关键词 杜氏肌营养不良 dmd基因 Alu元件 插入突变 白发
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Miniature tunable Airy beam optical meta-device 被引量:5
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作者 Jing Cheng Zhang Mu Ku Chen +6 位作者 Yubin Fan Qinmiao Chen Shufan Chen Jin Yao Xiaoyuan Liu Shumin Xiao Din Ping Tsai 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第2期5-12,共8页
Tunable Airy beams with controllable propagation trajectories have sparked interest in various fields,such as optical manipulation and laser fabrication.Existing research approaches encounter challenges related to ins... Tunable Airy beams with controllable propagation trajectories have sparked interest in various fields,such as optical manipulation and laser fabrication.Existing research approaches encounter challenges related to insufficient compactness and integration feasibility,or they require enhanced tunability to enable real-time dynamic manipulation of the propagation trajectory.In this work,we present a novel method that utilizes a dual metasurface system to surpass these limitations,significantly enhancing the practical potential of the Airy beam.Our approach involves encoding a cubic phase profile and two off-axis Fresnel lens phase profiles across the two metasurfaces.The validity of the proposed strategy has been confirmed through simulation and experimental results.The proposed meta-device addresses the existing limitations and lays the foundation for broadening the applicability of Airy beams across diverse domains,encompassing light-sheet microscopy,laser fabrication,optical tweezers,etc. 展开更多
关键词 metasurface miniature device tunable Airy beam tunable meta-device
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An Environment‑Tolerant Ion‑Conducting Double‑Network Composite Hydrogel for High‑Performance Flexible Electronic Devices 被引量:4
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作者 Wenchao Zhao Haifeng Zhou +3 位作者 Wenkang Li Manlin Chen Min Zhou Long Zhao 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第5期352-369,共18页
High-performance ion-conducting hydrogels(ICHs)are vital for developing flexible electronic devices.However,the robustness and ion-conducting behavior of ICHs deteriorate at extreme tempera-tures,hampering their use i... High-performance ion-conducting hydrogels(ICHs)are vital for developing flexible electronic devices.However,the robustness and ion-conducting behavior of ICHs deteriorate at extreme tempera-tures,hampering their use in soft electronics.To resolve these issues,a method involving freeze–thawing and ionizing radiation technology is reported herein for synthesizing a novel double-network(DN)ICH based on a poly(ionic liquid)/MXene/poly(vinyl alcohol)(PMP DN ICH)system.The well-designed ICH exhibits outstanding ionic conductivity(63.89 mS cm^(-1) at 25℃),excellent temperature resistance(-60–80℃),prolonged stability(30 d at ambient temperature),high oxidation resist-ance,remarkable antibacterial activity,decent mechanical performance,and adhesion.Additionally,the ICH performs effectively in a flexible wireless strain sensor,thermal sensor,all-solid-state supercapacitor,and single-electrode triboelectric nanogenerator,thereby highlighting its viability in constructing soft electronic devices.The highly integrated gel structure endows these flexible electronic devices with stable,reliable signal output performance.In particular,the all-solid-state supercapacitor containing the PMP DN ICH electrolyte exhibits a high areal specific capacitance of 253.38 mF cm^(-2)(current density,1 mA cm^(-2))and excellent environmental adaptability.This study paves the way for the design and fabrication of high-performance mul-tifunctional/flexible ICHs for wearable sensing,energy-storage,and energy-harvesting applications. 展开更多
关键词 Ionic liquids Double-network hydrogels Temperature tolerance Multifunctionality Flexible electronic devices
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基于CYCBD和参数自适应DMD的滚动轴承微弱故障诊断
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作者 夏天赐 党章 +1 位作者 吕勇 余震 《武汉科技大学学报》 CAS 北大核心 2024年第3期200-211,共12页
在旋转机械故障诊断中,传感器采集到的滚动轴承振动信号容易受到多个激励源的耦合影响,特别是微弱故障特征往往淹没在背景噪声中,给故障诊断带来挑战。为了抑制无关激励源并增强故障特征,本文提出一种基于最大二阶循环平稳盲解卷积(CYC... 在旋转机械故障诊断中,传感器采集到的滚动轴承振动信号容易受到多个激励源的耦合影响,特别是微弱故障特征往往淹没在背景噪声中,给故障诊断带来挑战。为了抑制无关激励源并增强故障特征,本文提出一种基于最大二阶循环平稳盲解卷积(CYCBD)和参数自适应动态模式分解(DMD)的滚动轴承微弱故障诊断方法。首先根据包络谐波乘积谱(EHPS)估计CYCBD算法的关键参数循环频率α,将原始信号经CYCBD处理使故障特征得到增强;然后将CYCBD处理后的信号通过参数自适应DMD进一步消除残余噪声,其中DMD的最优截断秩参数r通过遗传算法自适应确定;最后通过包络谱分析来提取故障特征频率及倍频。仿真和试验结果证明了本方法的有效性。 展开更多
关键词 滚动轴承 故障诊断 最大二阶循环平稳盲解卷积 动态模式分解 遗传算法 参数自适应
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Recent developments in selective laser processes for wearable devices 被引量:2
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作者 Youngchan Kim Eunseung Hwang +3 位作者 Chang Kai Kaichen Xu Heng Pan Sukjoon Hong 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第4期517-547,共31页
Recently,the increasing interest in wearable technology for personal healthcare and smart virtual/augmented reality applications has led to the development of facile fabrication methods.Lasers have long been used to d... Recently,the increasing interest in wearable technology for personal healthcare and smart virtual/augmented reality applications has led to the development of facile fabrication methods.Lasers have long been used to develop original solutions to such challenging technological problems due to their remote,sterile,rapid,and site-selective processing of materials.In this review,recent developments in relevant laser processes are summarized under two separate categories.First,transformative approaches,such as for laser-induced graphene,are introduced.In addition to design optimization and the alteration of a native substrate,the latest advances under a transformative approach now enable more complex material compositions and multilayer device configurations through the simultaneous transformation of heterogeneous precursors,or the sequential addition of functional layers coupled with other electronic elements.In addition,the more conventional laser techniques,such as ablation,sintering,and synthesis,can still be used to enhance the functionality of an entire system through the expansion of applicable materials and the adoption of new mechanisms.Later,various wearable device components developed through the corresponding laser processes are discussed,with an emphasis on chemical/physical sensors and energy devices.In addition,special attention is given to applications that use multiple laser sources or processes,which lay the foundation for the all-laser fabrication of wearable devices. 展开更多
关键词 Selective laser process Wearable device Transformative approach Laser-induced graphene Ablation SINTERING Synthesis
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In Situ Atomic Reconstruction Engineering Modulating Graphene-Like MXene-Based Multifunctional Electromagnetic Devices Covering Multi-Spectrum 被引量:2
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作者 Ting‑Ting Liu Qi Zheng +4 位作者 Wen‑Qiang Cao Yu‑Ze Wang Min Zhang Quan‑Liang Zhao Mao‑Sheng Cao 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第9期247-261,共15页
With the diversified development of big data,detection and precision guidance technologies,electromagnetic(EM)functional materials and devices serving multiple spectrums have become a hot topic.Exploring the multispec... With the diversified development of big data,detection and precision guidance technologies,electromagnetic(EM)functional materials and devices serving multiple spectrums have become a hot topic.Exploring the multispectral response of materials is a challenging and meaningful scientific question.In this study,MXene/TiO_(2)hybrids with tunable conduction loss and polarization relaxation are fabricated by in situ atomic reconstruction engineering.More importantly,MXene/TiO_(2)hybrids exhibit adjustable spectral responses in the GHz,infrared and visible spectrums,and several EM devices are constructed based on this.An antenna array provides excellent EM energy harvesting in multiple microwave bands,with|S11|up to−63.2 dB,and can be tuned by the degree of bending.An ultra-wideband bandpass filter realizes a passband of about 5.4 GHz and effectively suppresses the transmission of EM signals in the stopband.An infrared stealth device has an emissivity of less than 0.2 in the infrared spectrum at wavelengths of 6-14μm.This work can provide new inspiration for the design and development of multifunctional,multi-spectrum EM devices. 展开更多
关键词 Graphene-like MXene hybrids Multi-spectral response Multi-function antenna Ultra-wideband bandpass filter Electromagnetic device
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Process,Material,and Regulatory Considerations for 3D Printed Medical Devices and Tissue Constructs 被引量:1
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作者 Wei Long Ng Jia An Chee Kai Chua 《Engineering》 SCIE EI CAS CSCD 2024年第5期146-166,共21页
Three-dimensional(3D)printing is a highly automated platform that facilitates material deposition in a layer-by-layer approach to fabricate pre-defined 3D complex structures on demand.It is a highly promising techniqu... Three-dimensional(3D)printing is a highly automated platform that facilitates material deposition in a layer-by-layer approach to fabricate pre-defined 3D complex structures on demand.It is a highly promising technique for the fabrication of personalized medical devices or even patient-specific tissue constructs.Each type of 3D printing technique has its unique advantages and limitations,and the selection of a suitable 3D printing technique is highly dependent on its intended application.In this review paper,we present and highlight some of the critical processes(printing parameters,build orientation,build location,and support structures),material(batch-to-batch consistency,recycling,protein adsorption,biocompatibility,and degradation properties),and regulatory considerations(sterility and mechanical properties)for 3D printing of personalized medical devices.The goal of this review paper is to provide the readers with a good understanding of the various key considerations(process,material,and regulatory)in 3D printing,which are critical for the fabrication of improved patient-specific 3D printed medical devices and tissue constructs. 展开更多
关键词 3D printing BIOPRINTING BIOFABRICATION Medical devices Tissue constructs
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A mixed-coordination electron trapping-enabled high-precision touch-sensitive screen for wearable devices 被引量:1
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作者 Xi Zhang Junchi Ma +5 位作者 Hualin Deng Jinming Zhong Kaichen Xu Qiang Wu Bo Wen Dongfeng Diao 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第4期413-427,共15页
Touch-sensitive screens are crucial components of wearable devices.Materials such as reduced graphene oxide(rGO),carbon nanotubes(CNTs),and graphene offer promising solutions for flexible touch-sensitive screens.Howev... Touch-sensitive screens are crucial components of wearable devices.Materials such as reduced graphene oxide(rGO),carbon nanotubes(CNTs),and graphene offer promising solutions for flexible touch-sensitive screens.However,when stacked with flexible substrates to form multilayered capacitive touching sensors,these materials often suffer from substrate delamination in response to deformation;this is due to the materials having different Young’s modulus values.Delamination results in failure to offer accurate touch screen recognition.In this work,we demonstrate an induced charge-based mutual capacitive touching sensor capable of high-precision touch sensing.This is enabled by electron trapping and polarization effects related to mixed-coordinated bonding between copper nanoparticles and vertically grown graphene nanosheets.Here,we used an electron cyclotron resonance system to directly fabricate graphene-metal nanofilms(GMNFs)using carbon and copper,which are firmly adhered to flexible substrates.After being subjected to 3000 bending actions,we observed almost no change in touch sensitivity.The screen interaction system,which has a signal-to-noise ratio of 41.16 dB and resolution of 650 dpi,was tested using a handwritten Chinese character recognition trial and achieved an accuracy of 94.82%.Taken together,these results show the promise of touch-sensitive screens that use directly fabricated GMNFs for wearable devices. 展开更多
关键词 Flexible touch-sensitive screen Graphene-metal nanofilms Mixed coordination Wearable device
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双吸泵作液力透平叶轮内非定常流动DMD分析
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作者 苗森春 刘乐琪 +2 位作者 王晓晖 杨军虎 吴江波 《农业机械学报》 EI CAS CSCD 北大核心 2024年第6期150-158,共9页
为了精确分析双吸泵作液力透平叶轮内的非定常流动特性,采用SST k-ω湍流模型在设计工况下进行数值模拟。对一个周期的非定常速度场进行动态模态分解(DMD),并结合Q准则,得到前4阶主要模态及其相应的时空信息。分析结果表明:DMD方法将叶... 为了精确分析双吸泵作液力透平叶轮内的非定常流动特性,采用SST k-ω湍流模型在设计工况下进行数值模拟。对一个周期的非定常速度场进行动态模态分解(DMD),并结合Q准则,得到前4阶主要模态及其相应的时空信息。分析结果表明:DMD方法将叶轮内复杂的流场特征分解为动静干扰模态、基本模态和耗散模态。其中动静干扰模态占主导地位,频率为叶轮旋转频率,反映出叶轮内流动受静止部件干扰的流动特征,涡结构主要为点状涡和不连续的管状涡;基本模态频率为0Hz,反映出叶片流道几何特征引起的稳态流场特征,涡结构主要为连续的管状涡;3阶及4阶模态为耗散模态,反映出叶轮内流动受静止部件干扰,在叶片上产生的流动分离及不稳定涡结构脱落的特征,以片状涡和不连续的管状涡为主。在特定频率下DMD方法可以对叶轮流场结构进行分解,能够清楚地分析双吸泵作液力透平叶轮内复杂流场的非定常特性。 展开更多
关键词 双吸泵作液力透平 非定常流动 动态模态分解 相干结构 Q准则
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Application value research of swallowing treatment device combined with swallowing rehabilitation training in the treatment of swallowing disorders after stroke 被引量:2
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作者 Huan Xu Mei Chen +4 位作者 Yu-Li Wu Ya-Fen Lu Xin Wang Wei Jiang Yuan-Ying Zhang 《World Journal of Clinical Cases》 SCIE 2024年第21期4618-4625,共8页
BACKGROUND Stroke is a common disabling disease,whether it is ischemic stroke or hemorrhagic stroke,both can result in neuronal damage,leading to various manifestations of neurological dysfunction.AIM To explore of th... BACKGROUND Stroke is a common disabling disease,whether it is ischemic stroke or hemorrhagic stroke,both can result in neuronal damage,leading to various manifestations of neurological dysfunction.AIM To explore of the application value of swallowing treatment device combined with swallowing rehabilitation training in the treatment of swallowing disorders after stroke.METHODS This study selected 86 patients with swallowing disorders after stroke admitted to our rehabilitation department from February 2022 to December 2023 as research subjects.They were divided into a control group(n=43)and an observation group(n=43)according to the treatment.The control group received swallowing rehabilitation training,while the observation group received swallowing treatment device in addition to the training.Both groups underwent continuous intervention for two courses of treatment.RESULTS The total effective rate in the observation group(93.02%)was higher than that in the control group(76.74%)(P=0.035).After intervention,the oral transit time,swallowing response time,pharyngeal transit time,and laryngeal closure time decreased in both groups compared to before intervention.In the observation group,the oral transit time,swallowing response time,and pharyngeal transit time were shorter than those in the control group after intervention.However,the laryngeal closure time after intervention in the observation group was compared with that in the control group(P=0.142).After intervention,average amplitude value and duration of the genioglossus muscle group during empty swallowing and swallowing 5 mL of water are reduced compared to before intervention in both groups.After intervention,the scores of the chin-tuck swallowing exercise and the Standardized Swallowing Assessment are both reduced compared to pre-intervention levels in both groups.However,the observation group scores lower than the control group after intervention.Additionally,the Functional Oral Intake Scale scores of both groups are increased after intervention compared to pre-intervention levels,with the observation group scoring higher than the control group after intervention(P<0.001).The cumulative incidence of complications in the observation group is 9.30%,which is lower than the 27.91%in the control group(P=0.027).CONCLUSION The combination of swallowing therapy equipment with swallowing rehabilitation training can improve the muscle movement level of the genioglossus muscle group,enhance swallowing function,and prevent the occurrence of swallowing-related complications after stroke. 展开更多
关键词 Swallowing therapy device Swallowing rehabilitation training STROKE Swallowing disorder Swallowing function
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基于FPGA与DMD的微型近红外光谱采集系统设计
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作者 谢振坤 王硕 魏志鹏 《仪表技术与传感器》 CSCD 北大核心 2024年第11期61-65,共5页
为解决DMD型近红外光谱仪采集时间长、光谱实时性较低的问题,提出采用现场可编程门阵列(FPGA)作为主控单元,以DMD为核心的近红外光谱采集系统设计。FPGA控制图案数据通过24 bit的并行接口实时传输,驱动DMD选通入射光,同时进行A/D转换,... 为解决DMD型近红外光谱仪采集时间长、光谱实时性较低的问题,提出采用现场可编程门阵列(FPGA)作为主控单元,以DMD为核心的近红外光谱采集系统设计。FPGA控制图案数据通过24 bit的并行接口实时传输,驱动DMD选通入射光,同时进行A/D转换,实现光谱数据快速采集。对于阿达玛矩阵适配数字微镜面的问题,FPGA图案显示设计中,将常规阿达玛编码模板拆分为适配DMD微镜面的编码图案。最后通过样品采集实验对系统的性能进行测试验证,结果表明在900~1 700 nm的工作波段内,214个样本点的平均信噪比达到4 600∶1;在连续采集模式下,系统单次采集耗时优于0.147 s,满足工作中光谱实时采集的应用需求。 展开更多
关键词 数字微镜振列 近红外光谱 数据采集 信号处理 现场可编程门阵列 信噪比
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POD和DMD方法对燃料棒流致振动特性的分析
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作者 闵光云 姜乃斌 《原子能科学技术》 EI CAS CSCD 北大核心 2024年第10期2162-2172,共11页
燃料棒的流致振动是造成燃料失效和反应堆停堆的重要因素之一,研究其流致振动机理非常必要。本文建立了燃料棒的高保真有限元模型,基于ANSYS Batch和随机振动理论批量计算了不同支撑刚度下燃料棒的流致振动响应,并搭建了1个流致振动响... 燃料棒的流致振动是造成燃料失效和反应堆停堆的重要因素之一,研究其流致振动机理非常必要。本文建立了燃料棒的高保真有限元模型,基于ANSYS Batch和随机振动理论批量计算了不同支撑刚度下燃料棒的流致振动响应,并搭建了1个流致振动响应数据库。该数据库采用不同支撑刚度值来模拟和检查燃料棒可能遇到的情况。基于数据库组装快照矩阵,采用两种数据驱动方法(POD方法和DMD方法)搭建了1个高保真降阶模型(ROM),该ROM能够实现流致振动响应的快速重构。对比了POD方法和DMD方法重构燃料棒流致振动响应的效果以及各自的优点和缺点。研究发现:使用相同数量的模态重构燃料棒的流致振动响应时,POD方法的重构效果优于DMD方法;基于相同数量的模态重构时,刚度为1 N/mm的重构效果最差,这主要是因为刚度越小,频率越小,系统的振幅越大,需要更多数量的模态才能捕捉大幅振动带来的影响;DMD方法不仅能够高效地重构燃料棒的振动响应,还能够判断每个DMD模态的稳定性。 展开更多
关键词 POD dmd 流致振动 模态 燃料棒
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