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基于模糊熵的X射线图像局部对比度拉伸增强算法

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测试技术学报 2023年第1期37卷 29-36页

作者：郭牛桂志国刘祎康嘉琦中北大学省部共建动态测试技术国家重点实验室山西太原030051 中北大学信息与通信工程学院山西太原030051

在基于X射线的工件缺陷检测中,X射线图像往往存在亮度低、对比度低的问题。传统的局部对比度拉伸方法在增强图像的同时,容易引入噪音和光晕效应。针对此问题,提出了一种基于模糊熵的X射线图像局部对比度拉伸增强算法,该算法通过引入图... 详细信息

在基于X射线的工件缺陷检测中,X射线图像往往存在亮度低、对比度低的问题。传统的局部对比度拉伸方法在增强图像的同时,容易引入噪音和光晕效应。针对此问题,提出了一种基于模糊熵的X射线图像局部对比度拉伸增强算法,该算法通过引入图像模糊熵来控制局部区域的对比度拉伸,使图像均匀区域和边缘区域得到了不同程度的对比度拉伸。实验结果表明,该算法在增强图像细节的同时对噪声和边缘光晕现象进行了削弱,增强了图像的整体质量。

关键词： X射线图像模糊熵局部对比度拉伸图像细节

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城市植被遥感分类研究进展与展望

浙江大学学报（农业与生命科学版） 2024年第2期50卷 190-199页

作者：孟庆岩杜弘宇王莉萍张琳琳吴嘉豪康佳琦中国科学院空天信息创新研究院北京100094 杭州国际城市学研究中心浙江省城市治理研究中心浙江杭州310000 海南空天信息研究院海南省地球观测重点实验室海南三亚572029 中国科学院大学北京100049 澳门大学智慧城市物联网国家重点实验室中国澳门999078 桂林电子科技大学生命与环境科学学院广西桂林541004

城市植被是城市环境的重要组成部分,城市植被遥感分类是对城市绿度空间监测分析的重要方式。本文通过梳理国内外城市植被遥感分类研究进展,从遥感数据源和分类方法入手,分析该领域目前面临的问题及发展趋势,以期为城市绿度空间研究提供... 详细信息

城市植被是城市环境的重要组成部分,城市植被遥感分类是对城市绿度空间监测分析的重要方式。本文通过梳理国内外城市植被遥感分类研究进展,从遥感数据源和分类方法入手,分析该领域目前面临的问题及发展趋势,以期为城市绿度空间研究提供参考。首先,概述了光学数据、激光雷达数据及地面传感数据等数据源在城市植被遥感分类领域的应用,对不同数据源的优势与不足进行了深入分析;其次,基于阈值分割、机器学习和深度学习3种分类方法的研究,总结了应用于城市植被遥感分类领域各方法的特点;最后,提出了城市植被遥感分类研究中现存问题和未来发展方向。

关键词：城市植被城市遥感图像分类

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Investigating Müller glia reprogramming in mice: a retrospective of the last decade, and a look to the future

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Neural Regeneration Research 2025年第4期20卷 946-959页

作者： Zhiyuan Yin Jiahui kang Xuan Cheng Hui Gao Shujia Huo Haiwei Xu Key Lab of Visual Damage and Regeneration&Restoration of Chongqing Southwest Eye HospitalSouthwest HospitalThird Military Medical University(Army Medical University)ChongqingChina

Müller glia,as prominent glial cells within the retina,plays a significant role in maintaining retinal homeostasis in both healthy and diseased *** lower vertebrates like zebrafish,these cells assume responsibility for spontaneous retinal regeneration,wherein endogenous Müller glia undergo proliferation,transform into Müller glia-derived progenitor cells,and subsequently regenerate the entire retina with restored ***,Müller glia in the mouse and human retina exhibit limited neural reprogramming.Müller glia reprogramming is thus a promising strategy for treating neurodegenerative ocular disorders.Müller glia reprogramming in mice has been accomplished with remarkable success,through various *** in molecular,genetic,epigenetic,morphological,and physiological evaluations have made it easier to document and investigate the Müller glia programming process in ***,there remain issues that hinder improving reprogramming efficiency and ***,understanding the reprogramming mechanism is crucial toward exploring factors that will improve Müller glia reprogramming efficiency,and for developing novel Müller glia reprogramming *** review describes recent progress in relatively successful Müller glia reprogramming *** also provides a basis for developing new Müller glia reprogramming strategies in mice,including epigenetic remodeling,metabolic modulation,immune regulation,chemical small-molecules regulation,extracellular matrix remodeling,and cell-cell fusion,to achieve Müller glia reprogramming in mice.

关键词： cell fusion chemical small-molecules epigenetic extracellular matrix immune metabolic mice Müller glia neurodegenerative diseases reprogramming retina regeneration

The autophagy-lysosome pathway:a potential target in the chemical and gene therapeutic strategies for Parkinson’s disease

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Neural Regeneration Research 2025年第1期20卷 139-158页

作者： Fengjuan Jiao Lingyan Meng kang Du Xuezhi Li School of Mental Health Jining Medical UniversityJiningShandong ProvinceChina Shandong Collaborative Innovation Center for Diagnosis Treatment and Behavioral Interventions of Mental DisordersInstitute of Mental HealthJining Medical UniversityJiningShandong ProvinceChina

Parkinson’s disease is a common neurodegenerative disease with movement disorders associated with the intracytoplasmic deposition of aggregate proteins such asα-synuclein in *** one of the major intracellular degradation pathways,the autophagy-lysosome pathway plays an important role in eliminating these *** evidence has shown that upregulation of the autophagy-lysosome pathway may contribute to the clearance ofα-synuclein aggregates and protect against degeneration of dopaminergic neurons in Parkinson’s ***,multiple genes associated with the pathogenesis of Parkinson’s disease are intimately linked to alterations in the autophagy-lysosome ***,this pathway appears to be a promising therapeutic target for treatment of Parkinson’s *** this review,we briefly introduce the machinery of ***,we provide a description of the effects of Parkinson’s disease–related genes on the autophagy-lysosome ***,we highlight the potential chemical and genetic therapeutic strategies targeting the autophagy–lysosome pathway and their applications in Parkinson’s disease.

关键词： autophagy chemical therapy gene therapy Parkinson’s disease α-synuclein

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汾河柴庄段典型污染物衰减系数试验研究

水科学与工程技术 2022年第2期 6-9页

作者：赵艳锋武宏娟康佳琪山西省水文水资源勘测总站太原030001 临汾市水文水资源勘测站山西临汾041000

河流污染物衰减系数是建立水质模型、预测污染物浓度变化、制定污染物控制方案的关键参数。为合理确定汾河下游水体污染物综合衰减系数,研究典型污染物氨氮、总磷衰减变化情况,在汾河柴庄段进行了水团追踪现场试验。采用一维水质模型计... 详细信息

河流污染物衰减系数是建立水质模型、预测污染物浓度变化、制定污染物控制方案的关键参数。为合理确定汾河下游水体污染物综合衰减系数,研究典型污染物氨氮、总磷衰减变化情况,在汾河柴庄段进行了水团追踪现场试验。采用一维水质模型计算和四分位法统计分析,确定低温枯水期汾河下游柴庄段氨氮综合衰减系数范围0.606~1.089d^(-1),取值指导值0.847d^(-1);总磷综合衰减系数范围0.296~0.520d^(-1),取值指导值0.374d^(-1)。试验条件下,氨氮和总磷衰减效率较高,衰减过程主要依靠吸附、沉降等物理化学过程,衰减效率受初始浓度影响明显,初始浓度越高衰减系数越大。

关键词：衰减系数氨氮总磷汾河

WO_3/TiO_2复合薄膜的制备及其电致变色性能

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复合材料学报 2019年第4期36卷 914-920页

作者：成明杨继凯杨馥瑜亢嘉琪张宇飞陈张笑雄赵一铭王国政长春理工大学理学院长春130000

使用水热法在掺氟SnO_2涂覆的导电玻璃(FTO)基板上生长TiO_2纳米线,随后在TiO_2纳米线上采用水热法生长WO_3纳米线,制备出WO_3/TiO_2复合薄膜。通过循环伏安法(CV)、计时电流法(CA)、计时电量法(CC)等电化学测试技术研究了WO_3/TiO_2复... 详细信息

使用水热法在掺氟SnO_2涂覆的导电玻璃(FTO)基板上生长TiO_2纳米线,随后在TiO_2纳米线上采用水热法生长WO_3纳米线,制备出WO_3/TiO_2复合薄膜。通过循环伏安法(CV)、计时电流法(CA)、计时电量法(CC)等电化学测试技术研究了WO_3/TiO_2复合薄膜的电致变色性能;采用紫外分光光度计对薄膜的着色﹑漂白状态的响应时间进行测试。通过以上测试,计算得到了薄膜的循环稳定性﹑光调制﹑着色效率和切换时间(Y和X)等参数。结果显示WO_3/TiO_2复合薄膜的电致变色性明显提高,其中WO_3/TiO_2复合薄膜可逆性增加了6%,着色效率提高了40.96cm^2/C。

关键词： TiO2 WO3 复合薄膜水热法电致变色

KNOT PLACEMENT FOR B-SPLINE CURVE APPROXIMATION VIA l_(∞,1)-NORM AND DIFFERENTIAL EVOLUTION ALGORITHM

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Journal of Computational Mathematics 2022年第4期40卷 589-606页

作者： jiaqi Luo Hongmei kang Zhouwang Yang School of Mathematical Sciences Soochow UniversitySuzhou 215008China School of Mathematical Sciences University of Science and Technology of ChinaHefei 230026China

In this paper,we consider the knot placement problem in B-spline curve approximation.A novel two-stage framework is proposed for addressing this *** the first step,the l_(∞,1)-norm model is introduced for the sparse selection of candidate knots from an initial knot *** this step,the knot number is *** the second step,knot positions are formulated into a nonlinear optimization problem and optimized by a global optimization algorithm—the differential evolution algorithm(DE).The candidate knots selected in the first step are served for initial values of the DE *** the candidate knots provide a good guess of knot positions,the DE algorithm can quickly *** advantage of the proposed algorithm is that the knot number and knot positions are determined *** with the current existing algorithms,the proposed algorithm finds approximations with smaller fitting error when the knot number is fixed in ***,the proposed algorithm is robust to noisy data and can handle with few data *** illustrate with some examples and applications.

关键词： B-spline curve approximation Knot placement l_(∞,1)-norm Differential Evolution algorithm

Potential role of tanycyte-derived neurogenesis in Alzheimer's disease

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Neural Regeneration Research 2025年第6期20卷 1599-1612页

作者： Guibo Qi Han Tang Jianian Hu Siying kang Song Qin Department of Anatomy Histologyand EmbryologySchool of Basic Medical SciencesFudan UniversityShanghaiChina State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science Fudan UniversityShanghaiChina

Tanycytes, specialized ependymal cells located in the hypothalamus, play a crucial role in the generation of new neurons that contribute to the neural circuits responsible for regulating the systemic energy balance. The precise coordination of the gene networks controlling neurogenesis in naive and mature tanycytes is essential for maintaining homeostasis in adulthood. However, our understanding of the molecular mechanisms and signaling pathways that govern the proliferation and differentiation of tanycytes into neurons remains limited. This article aims to review the recent advancements in research into the mechanisms and functions of tanycyte-derived neurogenesis. Studies employing lineage-tracing techniques have revealed that the neurogenesis specifically originating from tanycytes in the hypothalamus has a compensatory role in neuronal loss and helps maintain energy homeostasis during metabolic diseases. Intriguingly,metabolic disorders are considered early biomarkers of Alzheimer's disease. Furthermore,the neurogenic potential of tanycytes and the state of newborn neurons derived from tanycytes heavily depend on the maintenance of mild microenvironments, which may be disrupted in Alzheimer's disease due to the impaired blood–brain barrier ***, the specific alterations and regulatory mechanisms governing tanycyte-derived neurogenesis in Alzheimer's disease remain unclear. Accumulating evidence suggests that tanycyte-derived neurogenesis might be impaired in Alzheimer's disease, exacerbating neurodegeneration. Confirming this hypothesis, however, poses a challenge because of the lack of long-term tracing and nucleus-specific analyses of newborn neurons in the hypothalamus of patients with Alzheimer's disease. Further research into the molecular mechanisms underlying tanycyte-derived neurogenesis holds promise for identifying small molecules capable of restoring tanycyte proliferation in neurodegenerative diseases. This line of investigation could pro

关键词： Alzheimer's disease blood–brain barrier ependymoglial cells hypothalamus metabolic diseases neural stem cells neurogenesis neuroinflammatory diseases neurons tanycyte

Adaptive controller design for satellite attached by non-cooperative object

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Chinese Journal of Aeronautics 2020年第3期33卷 1006-1015页

作者： Guohua kang jiaqi WU Chendi JIN Xuefen CHEN College of Astronautics Nanjing University of Aeronautics&AstronauticsNanjing 210016China Nanjing Changfeng Aerospace Electronic Technology Co.Ltd Nanjing 210013China

When non-cooperative body attachment occurs in space, the inertia of the new combination and the change of the system's momentum are *** uncertainty may lead to the instability of the spacecraft's attitude *** order to solve this problem, we propose an adaptive control scheme based on the inertia estimation of the new, combined system of non-cooperative body and *** method can allow the new combination of different situations to reach a stable state with a high level of precision and *** this paper, the stability of the adaptive control scheme is proven by constructing a Lyapunov function.A simulation environment in which a non-cooperative body attaches to a satellite attaches to is *** simulation shows that the attitude error converges to a small field when using the control scheme, regardless of unfavorable cases, including unknown inertia parameters, added *** addition, the simulation results show the strong robustness of the control scheme for the new combination.

关键词： Adaptive control scheme Inertia estimation New combination Non-cooperative body attachment Robustness