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Chinese Journal of Polymer Science 2020年第11期38卷 1239-1247,I0008页

作者： Lu Jin Yan Zheng Ze-Kun liu jia-shen li Yang-Pei-Qi Yi Yang-Yang Fan Lu-Lu Xu Yi li Department of Materials School of Natural SciencesThe University of ManchesterManchester Ml 39PLU.K. School of Fashion Zhongyuan University of TechnologyZhengzhou 450007China

Electrospun poly(vinylidene fluoride)(PVDF)nanofiber web has been widely utilized as a functional material in various flexible sensors and generators due to its high piezoelectricity,ease processability,and low *** all the crystalline phases of PVDF,β-phase is a key property for PVDF nano fiber web,because the con tent of β-phase is directly proporti onal to piezoelectric performa nee of PVDF nano fiber ***,the impact of graphe ne con tent(GC),tip-to-collector dista nee(TCD),and rotational speed of collector(RSC),as well as their interactions on theβ-phase formation of PVDF nano fiber web is systematically investigated via design of experime ntal *** fraction of each crystalline phase of PVDF nano fiber web is calculated by FTIR spectra,and the crystallinity is determined by XRD *** influences of GC,TCD,and RSC on both β-phase fraction and crystallinity of PVDF nanofiber are analyzed using Minitab *** results show that GC,TCD,and RSC all have significa nt effect on the β-phase content of PVDF nano fiber web,and GC is the most significant *** addition,an optimal electrospinning condition(GC=1 wt%,TCD=4 cm,and RSC=2000 r·min^-1)to fabricate high 0-phase crystallinity of PVDF nanofiber web is drawn,under which the crystallinity can reach 41.7%.The contributions in this study could provide guidanee for future research on fabricating high performance PVDF nanofiber web based sensors or generators.

关键词： Graphene Electrospinning Poly(vinylidene fluoride) Design of experiment βCrystal phase

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水或液氮中电弧放电制备炭纳米材料(英文)

新型炭材料 2007年第4期22卷 337-341页

作者：邢刚贾申利史宗谦电力设备电气绝缘国家重点实验室

利用特制的电弧放电装置,研究了水或液氮中碳电弧放电形成炭纳米材料的机理。借助高分辨率透射电子显微镜对电弧放电生成的产物进行了观察和分析。结果表明:在水或液氮中碳电弧放电可以生成多壁碳纳米管和碳纳米洋葱结构,液氮中碳电弧... 详细信息

利用特制的电弧放电装置,研究了水或液氮中碳电弧放电形成炭纳米材料的机理。借助高分辨率透射电子显微镜对电弧放电生成的产物进行了观察和分析。结果表明:在水或液氮中碳电弧放电可以生成多壁碳纳米管和碳纳米洋葱结构,液氮中碳电弧放电可以生成单壁碳纳米角,水中钴催化碳电弧放电可以生成碳包裹的纳米钴颗粒。横向低频交变磁场会影响碳纳米材料的形核过程,并且可以推测磁场交变的频率5Hz与纳米管、纳米洋葱等结构的生长周期存在某种拟合。根据实验现象,提出了一种解释液体中碳电弧放电过程纳米材料生成的理论模型。

关键词：电弧炭纳米材料制备

基于振动信号小波包提取和短时能量分析的高压断路器合闸同期性的研究

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中国电机工程学报 2005年第13期25卷 149-154页

作者：马强荣命哲贾申利西安交通大学电力设备电气绝缘国家重点实验室陕西省西安市710049

该文提出了一种分析高压断路器合闸同期性的新方法:将小波包提取算法和短时能量分析方法相结合,利用小波包分解与重构原理将断路器合闸振动信号分解到不同频段中,并对代表高频冲击信号的分解系数进行重构,然后运用短时能量分析方法对重... 详细信息

该文提出了一种分析高压断路器合闸同期性的新方法:将小波包提取算法和短时能量分析方法相结合,利用小波包分解与重构原理将断路器合闸振动信号分解到不同频段中,并对代表高频冲击信号的分解系数进行重构,然后运用短时能量分析方法对重构后的信号进行分析,辨识出合闸变位点。通过对三相合闸过程的分析,得出三相同期性。通过MATLAB仿真分析和实验结果验证了该方法的有效性。

关键词：高压断路器小波包短时能量合闸同期性振动信号

Merging bound states in the continuum in an open acoustic resonator

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 124-131页

作者： Lujun Huang Bin jia Artem S.Pilipchuk Sibo Huang Chen shen Almas F.Sadreev Yong li Andrey E.Miroshnichenko School of Physics and Electronic Sciences East China Normal University Institute of Acoustics Tongji University L.V.Kirensky Institute of Physics Department of Mechanical Engineering Rowan University School of Engineering and Technology University of New South Wales at Canberra

Bound states in the continuum （BICs） are perfectly localized resonances despite embedding in the continuum ***,an isolated BIC is very sensitive to the structure ***,we report merging acoustic BICs in a single open resonator,robust against the structure *** find that both symmetry-protected BIC and Friedrich-Wintgen BIC are sustained in a single coupled waveguide-resonator *** varying the height and length of the resonator,these two BICs move toward each other and merge into a single one at a critical *** to an individual BIC,the merged BIC is robust against fabrication error because its Q-factor is proportional to ΔL-4,whereΔL embodies the structure *** essence of this extraordinary phenomenon is perfectly explained by the two-and three-level approximations of the effective nonHermitian ***,we present direct experimental demonstrations of the moving and merging of BICs in a coupled 3D waveguide-resonator,which are evidenced by the vanishing of the linewidth of Fano resonance in the transmission *** results may find exciting applications in designing high-quality acoustic sources,sensors and filters.

关键词： acoustic resonances bound state in the continuum high-Q resonances

Design and application of biodegradable coronary stents： what will be brought by further innovations in materials science？

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中国组织工程研究 2014年第30期18卷 4878-4888页

作者： Chen jia-hui shen li Wang Qi-bing Ge Jun-bo Department of Cardiology Zhongshan Hospital Shanghai Institute of Cardiovascular Diseases Fudan University Shanghai 200032 China

BACKGROUND:With the social and economic development and aging, coronary heart disease has become the primary cause of death endangering human life and health, while cardiovascular intervention (especially stenting) in the treatment of cardiovascular disease is at a growing status. OBJECTIVE; To describe the development, research progress and latest clinical application of heart interventional materials as well as advantages and disadvantages of biodegradable stents, and meanwhile to prospect for its future development and improvement. METHODS:A computer-based online search was conducted in PubMed for English language publications from January 1999 to April 2014 using the key words of"stent, scaffold, bioabsorbable, bioresorbable, biodegradable, biocompatibility, material properties" in English. RESULTS AND CONCLUSION:The new fully biodegradable stents are considered as another major progress in the cardiac intervention, which brings a new gospel for patients with coronary heart disease, in the initial stage of implantation, biodegradable stents exhibit the same mechanical support as bare metal stents; after implantation, anti-proliferative drugs are released to prevent thrombosis and restenosis, and the stent is completely degraded within a specified period, which significantly reduces the late-stage and very late-stage thrombosis and the risk of in-stent restenosis. However, long-term safety and efficacy of biodegradable stents need further studies. Innovation of stent design and materials science is the key to overcome the current shortcomings of biodegradable stents.

关键词：冠心病治疗方法临床分析冠状动脉性心脏病

超声功率-凝固压力协同作用对真空差压铸造铝合金二次枝晶间距的影响

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中国有色金属学报 2017年第1期27卷 51-56页

作者：严青松芦刚李成沈加利南昌航空大学航空制造工程学院南昌330063

通过测试与分析不同超声功率与凝固压力下真空差压铸造ZL114A铝合金的二次枝晶间距,研究超声功率与凝固压力协同作用对真空差压铸造铝合金二次枝晶间距的影响,建立真空差压铸造ZL114A铝合金二次枝晶间距与超声功率及凝固压力的关系。结... 详细信息

通过测试与分析不同超声功率与凝固压力下真空差压铸造ZL114A铝合金的二次枝晶间距,研究超声功率与凝固压力协同作用对真空差压铸造铝合金二次枝晶间距的影响,建立真空差压铸造ZL114A铝合金二次枝晶间距与超声功率及凝固压力的关系。结果表明:在超声功率和凝固压力协同作用下,超声效应与凝固压力挤渗效应共同影响真空差压铸造铝合金二次枝晶间距;在超声功率600 W与凝固压力350 kPa协同作用下,真空差压铸造铝合金二次枝晶间距最小;当凝固压力小于300 kPa时,超声功率对铝合金二次枝晶间距影响较大;当凝固压力大于300 kPa时,凝固压力对真空差压铸造ZL114A铝合金二次枝晶间距影响较大。

关键词：铝合金二次枝晶间距超声功率凝固压力真空差压铸造

现场可编程门阵列在开关设备在线监测中的应用

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高压电器 2005年第2期41卷 107-109,112页

作者：马强荣命哲李琨贾申利西安交通大学电力设备电气绝缘国家重点实验室陕西西安710049

利用现场可编程门阵列可靠性高、通用性强、可重构等优点,设计出用于开关设备状态在线监测的专用芯片。该芯片集采集、计量、通讯、报警功能于一体,配以少量的外围器件,便可实时监测开关设备的温度、机械、绝缘等各项状态参数。该芯片... 详细信息

利用现场可编程门阵列可靠性高、通用性强、可重构等优点,设计出用于开关设备状态在线监测的专用芯片。该芯片集采集、计量、通讯、报警功能于一体,配以少量的外围器件,便可实时监测开关设备的温度、机械、绝缘等各项状态参数。该芯片具有通用的通讯接口,可以与上位机通讯。与以往使用单片机实现开关设备状态在线监测的设计方案相比,该设计具有可重构、速度快、灵活性高的特点。

关键词：开关设备在线监测现场可编程门阵列

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土壤中红外光谱库支持下的局部建模集优化

红外与毫米波学报 2023年第6期42卷 816-824页

作者：沈佳丽陈颂超洪永胜李硕华中师范大学地理过程分析与模拟湖北省重点实验室湖北武汉430079 浙江大学杭州国际科创中心浙江杭州311200 浙江大学农业遥感与信息技术应用研究所浙江杭州310058 农业农村部光谱检测重点实验室浙江杭州310058

土壤中红外(MIR)光谱能快速、无污染、低成本地估算土壤有机碳等理化属性。随着各种尺度土壤光谱库的建立,使用其进行快速土壤分析引起广泛关注,但光谱库的通用模型在局部尺度上的预测效果不理想。开发“局部化”光谱建模方法是提高土... 详细信息

土壤中红外(MIR)光谱能快速、无污染、低成本地估算土壤有机碳等理化属性。随着各种尺度土壤光谱库的建立,使用其进行快速土壤分析引起广泛关注,但光谱库的通用模型在局部尺度上的预测效果不理想。开发“局部化”光谱建模方法是提高土壤光谱库性能的有效途径。本文提出了一种新的方法,通过光谱相似度计算和建模子集构建,旨在从库中快速建立最优局部建模集以提高预测精度。比较了欧氏、马氏、余弦三种距离算法衡量待测样本与库样本之间的相似度并生成距离矩阵;使用连续统去除法从距离矩阵中提取库容曲线中的特征点。利用偏最小二乘回归建立土壤MIR光谱与有机碳含量间的定量关系。结果表明,三种距离算法结合连续统去除得到的第一特征点均可得到较佳的预测精度。马氏距离不仅模型精度最高(R^(2)=0.764,RMSE=1.021%)而且用到的库样本数最少(14%库容)。本方法可改善MIR光谱分析的成本效率并能提高局部尺度的预测能力。

关键词：土壤碳相似度距离矩阵连续统去除偏最小二乘回归

Optimizing Fine-Tuning in Quantized Language Models:An In-Depth Analysis of Key Variables

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Computers, Materials & Continua 2025年第1期82卷 307-325页

作者： Ao shen Zhiquan Lai Dongsheng li Xiaoyu Hu National Key Laboratory of Parallel and Distributed Computing National University of Defense TechnologyChangsha410073China Strategic Assessments and Consultation Institute Academy of Military ScienceBeijing100091China

Large-scale Language Models(LLMs)have achieved significant breakthroughs in Natural Language Processing(NLP),driven by the pre-training and fine-tuning *** this approach allows models to specialize in specific tasks with reduced training costs,the substantial memory requirements during fine-tuning present a barrier to broader ***-Efficient Fine-Tuning(PEFT)techniques,such as Low-Rank Adaptation(LoRA),and parameter quantization methods have emerged as solutions to address these challenges by optimizing memory usage and computational *** these,QLoRA,which combines PEFT and quantization,has demonstrated notable success in reducing memory footprints during fine-tuning,prompting the development of various QLoRA *** these advancements,the quantitative impact of key variables on the fine-tuning performance of quantized LLMs remains *** study presents a comprehensive analysis of these key variables,focusing on their influence across different layer types and depths within LLM *** investigation uncovers several critical findings:(1)Larger layers,such as MLP layers,can maintain performance despite reductions in adapter rank,while smaller layers,like self-attention layers,aremore sensitive to such changes;(2)The effectiveness of balancing factors depends more on specific values rather than layer type or depth;(3)In quantization-aware fine-tuning,larger layers can effectively utilize smaller adapters,whereas smaller layers struggle to do *** insights suggest that layer type is a more significant determinant of fine-tuning success than layer depth when optimizing quantized ***,for the same discount of trainable parameters,reducing the trainable parameters in a larger layer is more effective in preserving fine-tuning accuracy than in a smaller *** study provides valuable guidance for more efficient fine-tuning strategies and opens avenues for further research into optimizing LLM

关键词： Large-scale Language Model Parameter-Efficient Fine-Tuning parameter quantization key variable trainable parameters experimental analysis

A Rapid Adaptation Approach for Dynamic Air‑Writing Recognition Using Wearable Wristbands with Self‑Supervised Contrastive Learning

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Nano-Micro Letters 2025年第2期17卷 417-431页

作者： Yunjian Guo Kunpeng li Wei Yue Nam‑Young Kim Yang li Guozhen shen Jong‑Chul Lee Department of Electronic Convergence Engineering Kwangwoon UniversitySeoul 01897South Korea Radio Frequency Integrated Circuit(RFIC)Bio Centre Kwangwoon UniversitySeoul 01897South Korea Department of Electronic Engineering Kwangwoon UniversitySeoul 01897South Korea School of Microelectronics Shandong UniversityJinan 250101People’s Republic of China State Key Laboratory of Integrated Chips and Systems Fudan UniversityShanghai 200433People’s Republic of China School of Integrated Circuits and Electronics Beijing Institute of TechnologyBeijing 100081People’s Republic of China

Wearable wristband systems leverage deep learning to revolutionize hand gesture recognition in daily *** existing approaches that often focus on static gestures and require extensive labeled data,the proposed wearable wristband with selfsupervised contrastive learning excels at dynamic motion tracking and adapts rapidly across multiple *** features a four-channel sensing array composed of an ionic hydrogel with hierarchical microcone structures and ultrathin flexible electrodes,resulting in high-sensitivity capacitance *** wireless transmission from a Wi-Fi module,the proposed algorithm learns latent features from the unlabeled signals of random wrist ***,only few-shot labeled data are sufficient for fine-tuning the model,enabling rapid adaptation to various *** system achieves a high accuracy of 94.9%in different scenarios,including the prediction of eight-direction commands,and air-writing of all numbers and *** proposed method facilitates smooth transitions between multiple tasks without the need for modifying the structure or undergoing extensive task-specific *** utility has been further extended to enhance human–machine interaction over digital platforms,such as game controls,calculators,and three-language login systems,offering users a natural and intuitive way of communication.

关键词： Wearable wristband Self-supervised contrastive learning Dynamic gesture Air-writing Human-machine interaction