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基于神经网络的人工肌非线性控制

上海交通大学学报 2001年第5期35卷 713-716页

作者：田社平林良明颜国正上海交通大学信息检测技术及仪器系上海200030

运用非线性控制的逆系统方法 ,提出了一种基于神经网络的人工肌非线性控制方案 .由原系统导出 n- m阶逆系统模型 ,并与原系统一起构成具有反馈结构的伪线性系统 ,从而可方便地运用线性控制理论完成对控制系统的设计 .用 BP神经网络逼近... 详细信息

运用非线性控制的逆系统方法 ,提出了一种基于神经网络的人工肌非线性控制方案 .由原系统导出 n- m阶逆系统模型 ,并与原系统一起构成具有反馈结构的伪线性系统 ,从而可方便地运用线性控制理论完成对控制系统的设计 .用 BP神经网络逼近逆系统模型 ,并借助于递推预报误差算法来训练神经网络 ,该算法与传统的 BP算法相比具有更好的收敛特性 .设计了一个具有单关节的人工肌试验系统 .给出了人工肌关节跟踪正弦波和矩形波参考信号的试验结果 .与传统的线性控制方案比较 ,基于神经网络的人工肌非线性控制方案能够得到更快的控制速度和更高的控制精度 .

关键词：人工肌神经网络逆系统方法非线性控制机器人

Unveiling an ancient whole-genome duplication event in Stentor,the model unicellular eukaryotes

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Science China Life Sciences 2025年

作者： Weibo zheng Chao Li Zhaorui Zhou Xiao Chen Michael Lynch Ying yan School of Life Sciences Ludong University Key Laboratory of Evolution & Marine Biodiversity (Ministry of Education) and Institute of Evolution & Marine Biodiversity Ocean University of China Biodesign Center for Mechanisms of Evolution Arizona State University Marine College Shandong University

Whole-genome duplication(WGD) events are widespread across eukaryotes and have played a significant role in moulding the genetic architectures of diverse organisms. In the present study, the newly sequenced genome of a giant ciliated protist, Stentor roeselii, provides an opportunity for the analysis of the collinearity and retention of reciprocal best-hit genes between two Stentor species. As a main result, we have unveiled a previously undetected ancient WGD event shaping the genome of its congener, Stentor coeruleus, a model protist used in cytological and evolutionary studies. Genomes of two congeners, S. coeruleus and S. roeselii, are compared and analyzed, revealing that:(i)the former exhibits a much higher retention rate of colinear-gene pairs(28%) than does S. roeselii, and in S. coeruleus, 75% of genes that have a RBH hit in S. roeselii, have paralogs with high amino-acid identity, consistent with a WGD event in the lineage leading to S. coeruleus;(ii) the S. roeselii genome possesses extremely short intergenic regions, implying that the lengths of intergenic regions are under strong selection;(iii) the unique characteristics of introns may have been shaped in the common ancestor of heterotrichs;(iv) gene families that play a role in activities of multiple protein kinases and voltage-gated ion channels expanded rapidly in the ancestor of both taxa, possibly relating to the remarkable regenerative ability in Stentor. This study offers new insights into the evolutionary dynamics of ciliate genomes,with implications for understanding of the processes underlying the evolution of genomic complexity.

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T cell interactions with microglia in immune-inflammatory processes of ischemic stroke

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Neural Regeneration Research 2025年第5期20卷 1277-1292页

作者： Yuxiao zheng Zilin Ren Ying Liu Juntang yan Congai Chen yanhui He Yuyu Shi Fafeng Cheng Qingguo Wang Changxiang Li Xueqian Wang School of Traditional Chinese Medicine Beijing University of Chinese MedicineBeijingChina Library Beijing University of Chinese MedicineBeijingChina Dongzhimen Hospital Beijing University of Chinese MedicineBeijingChina

The primary mechanism of secondary injury after cerebral ischemia may be the brain inflammation that emerges after an ischemic stroke,which promotes neuronal death and inhibits nerve tissue *** the first immune cells to be activated after an ischemic stroke,microglia play an important immunomodulatory role in the progression of the *** an ischemic stroke,peripheral blood immune cells(mainly T cells)are recruited to the central nervous system by chemokines secreted by immune cells in the brain,where they interact with central nervous system cells(mainly microglia)to trigger a secondary neuroimmune *** review summarizes the interactions between T cells and microglia in the immune-inflammatory processes of ischemic *** found that,during ischemic stroke,T cells and microglia demonstrate a more pronounced synergistic ***1,Th17,and M1 microglia can co-secrete proinflammatory factors,such as interferon-γ,tumor necrosis factor-α,and interleukin-1β,to promote neuroinflammation and exacerbate brain ***2,Treg,and M2 microglia jointly secrete anti-inflammatory factors,such as interleukin-4,interleukin-10,and transforming growth factor-β,to inhibit the progression of neuroinflammation,as well as growth factors such as brain-derived neurotrophic factor to promote nerve regeneration and repair brain *** interactions between microglia and T cells influence the direction of the subsequent neuroinflammation,which in turn determines the prognosis of ischemic stroke *** trials have been conducted on the ways to modulate the interactions between T cells and microglia toward anti-inflammatory communication using the immunosuppressant fingolimod or overdosing with Treg cells to promote neural tissue repair and reduce the damage caused by ischemic ***,such studies have been relatively infrequent,and clinical experience is still *** summary,in ischemic stroke,T cell subsets and activated micro

关键词： brain immune inflammation interaction ischemic stroke mechanism microglia neuron secondary injury T cells

Endoplasmic reticulum stress and autophagy in cerebral ischemia/reperfusion injury:PERK as a potential target for intervention

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Neural Regeneration Research 2025年第5期20卷 1455-1466页

作者： Ju zheng Yixin Li Ting Zhang yanlin Fu Peiyan Long Xiao Gao zhengwei Wang Zhizhong Guan Xiaolan Qi Wei Hong yan Xiao Key Laboratory of Endemic and Ethnic Diseases Ministry of Education&Key Laboratory of Medical Molecular Biology of Guizhou ProvinceGuizhou Medical UniversityGuiyangGuizhou ProvinceChina Guizhou Center for Disease Control and Prevention GuiyangGuizhou ProvinceChina Department of Histology and Embryology Guizhou Medical UniversityGuiyangGuizhou ProvinceChina Collaborative Innovation Center for Prevention and Control of Endemic and Ethnic Regional Diseases Co-constructed by the Province and Ministry GuiyangGuizhou ProvinceChina

Several studies have shown that activation of unfolded protein response and endoplasmic reticulum(ER)stress plays a crucial role in severe cerebral ischemia/reperfusion *** occurs within hours after cerebral ischemia,but the relationship between ER stress and autophagy remains *** this study,we established experimental models using oxygen-glucose deprivation/reoxygenation in PC12 cells and primary neurons to simulate cerebral ischemia/reperfusion *** found that prolongation of oxygen-glucose deprivation activated the ER stress pathway protein kinase-like endoplasmic reticulum kinase(PERK)/eukaryotic translation initiation factor 2 subunit alpha(e IF2α)-activating transcription factor 4(ATF4)-C/EBP homologous protein(CHOP),increased neuronal apoptosis,and induced ***,inhibition of ER stress using inhibitors or by si RNA knockdown of the PERK gene significantly attenuated excessive autophagy and neuronal apoptosis,indicating an interaction between autophagy and ER stress and suggesting PERK as an essential target for regulating *** autophagy with chloroquine exacerbated ER stress-induced apoptosis,indicating that normal levels of autophagy play a protective role in neuronal injury following cerebral ischemia/reperfusion *** from this study indicate that cerebral ischemia/reperfusion injury can trigger neuronal ER stress and promote autophagy,and suggest that PERK is a possible target for inhibiting excessive autophagy in cerebral ischemia/reperfusion injury.

关键词： apoptosis ATF4 autophagy C/EBP homologous protein cerebral ischemia/reperfusion injury eIF2α endoplasmic reticulum stress PERK

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中国各省耕地数量占补平衡趋势预测

资源科学 2007年第6期29卷 114-119页

作者：张琳张凤荣薛永森严良政中国农业大学资源与环境学院北京100094 国土资源部土地整理中心北京100035

1996年,出于保障国家粮食安全、控制耕地快速减少的考虑,我国实行了耕地总量动态平衡的土地管理政策。政策出台后,对建设占用耕地的势头起到了一定的遏制作用。但是,在未来一段时期内经济发展依然会继续占用耕地,而我国后备土地资源又... 详细信息

1996年,出于保障国家粮食安全、控制耕地快速减少的考虑,我国实行了耕地总量动态平衡的土地管理政策。政策出台后,对建设占用耕地的势头起到了一定的遏制作用。但是,在未来一段时期内经济发展依然会继续占用耕地,而我国后备土地资源又十分有限,那么未来耕地占补平衡的前景将会如何。基于此,本文分析了9年来各省(市、自治区)耕地被建设占用的情况及其同经济发展的关系,并结合耕地后备资源状况,预测了未来各地区耕地占补平衡的趋势。结果表明:①我国各地区建设占用耕地情况差异悬殊,并且同经济发展指标密切相关。年均占用数量最多的是山东省,最少的是西藏自治区,两者相差近百倍;②采用3种模型对各省建设占用耕地数量进行趋势外推得到:2010年,浙江省将无法实现耕地占补平衡;2015年,北京、上海、贵州和云南几省市也将无法现耕地占补平衡;③如果按照我国目前建设占用耕地的平均速度测算,即使不计成本与效益开发所有勉强可以耕种的土地,要维持占补平衡,可开发耕地资源潜力最多只能维持39年。而且将有一半的省市10年内就会将所有可开发为耕地的未利用地全部开发完毕。

关键词：耕地占补平衡各省预测

考虑碳排放的贵州省茶叶物流配送路径优化设计

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物流科技 2018年第10期41卷 9-12页

作者：薛亮郑琰余伟南京林业大学汽车与交通工程学院江苏南京210037

文章旨在对贵州省茶叶物流配送情况进行分析,针对贵州地区高原、山地为主的天然地理条件,从茶叶物流配送路径入手,结合当今主流低碳排放的要求,进行优化。降低碳排放,提高交通运输产业产值,减少交通运输带来的能源消耗和环境成本,对比... 详细信息

文章旨在对贵州省茶叶物流配送情况进行分析,针对贵州地区高原、山地为主的天然地理条件,从茶叶物流配送路径入手,结合当今主流低碳排放的要求,进行优化。降低碳排放,提高交通运输产业产值,减少交通运输带来的能源消耗和环境成本,对比贵州省黔中南区域到上海地区的不同路径,根据现有的物流配送体系进行计算,求出在碳排放约束条件下的最优路径,并对结果进行对比分析。

关键词：贵州省茶叶物流碳排放配送路径优化设计

Study of thermal decoherence of harmonic oscillators

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原子与分子物理学报 2025年第5期42卷 108-114页

作者： LI Jian ZHOU Gao-liang yan zheng-Xin LIU Wei WANG Zhao-Qi College of Science Xi’an University of Science and TechnologyXi’an 710054China

The thermal decoherence of harmonic oscillators is investigated *** quantum system presented here is a one-dimensional oscillator with angular frequency,which is surrounded by a thermal bath of environmental *** are various environmental oscillators with different angular frequency(below an ultraviolet cutoff).At the beginning,the quantum system is a pure state and the environmental oscillators are in thermodynamic equilibrium with *** a period,the system-environment interactions inspire significant decoherence of the quantum *** decoherence is displayed by explicit calculations of the purity and von Neumann entropy of the quantum *** is worth noting that the decoherence could be significant even in the weak coupling and low temperature case due to the large amount of environmental degrees of *** the decoherence process is inspired between the quantum system and an ordinary thermal environment here,the thermal decoherence result is quite general.

关键词： Quantum decoherence Grand canonical ensemble Oscillators

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我国环境保护规划的分析与展望

环境科学研究 2010年第6期23卷 782-788页

作者：董伟张勇张令阎振元张晓光何远光严良政大连市环境保护局辽宁大连116001 大连市环境科学设计研究院辽宁大连116023

回顾了我国环境保护规划的发展历程,剖析了当前我国环境保护规划存在的问题,认为现阶段我国环境保护规划存在缺乏法律效力、法律地位不足、规划编制不规范、设区的市缺少环境保护总体规划、规划衔接不够、实施监管机制不完善和公众参与... 详细信息

回顾了我国环境保护规划的发展历程,剖析了当前我国环境保护规划存在的问题,认为现阶段我国环境保护规划存在缺乏法律效力、法律地位不足、规划编制不规范、设区的市缺少环境保护总体规划、规划衔接不够、实施监管机制不完善和公众参与缺乏实质性等问题;对比分析了我国与美国和荷兰这2个发达国家的环境保护规划,总结了可以借鉴的国际经验;结合我国环境保护工作的形势和环境保护规划的发展,提出完善法律机制、设区的市编制环境保护总体规划、加强规划衔接、建立实施监管机制和加强公众参与等建议,确保其成为参与政府综合决策的有效手段,使其更加权威、规范和科学.

关键词：环境保护总体规划发展历程问题国际借鉴建议

创建环境保护总体规划在大连社会经济发展中的战略地位及实施思路

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环境科学研究 2010年第4期23卷 377-386页

作者：董伟张勇何远光阎振元张晓光张令严良政大连市环境保护局辽宁大连116001 大连市环境科学设计研究院辽宁大连116023

以建设资源节约型、环境友好型社会和生态宜居城市为总体目标,以全面贯彻落实科学发展观,促进经济增长方式转变和优化城市布局为主线,以建立良好的生态环境为核心,坚持环境保护与经济增长并重、与经济发展同步,全力推进生态文明建设,构... 详细信息

以建设资源节约型、环境友好型社会和生态宜居城市为总体目标,以全面贯彻落实科学发展观,促进经济增长方式转变和优化城市布局为主线,以建立良好的生态环境为核心,坚持环境保护与经济增长并重、与经济发展同步,全力推进生态文明建设,构建持续协调发展的生态经济体系、自然宜居的生态环境体系、责权明晰的生态环境执法和保障体系,建立了《大连市环境保护总体规划(2008—2020)》.该规划的指标体系是以《生态市建设指标》、《大连市城市总体规划》和《大连市生态环境保护"十一五"规划》中的相关指标为基础,通过污染物排放量预测、环境容量分析、资源承载力分析,比较分析了发达国家主要城市的环境质量目标,综合考虑了环境质量标准而设定.采用数值模拟,系统分析,动态分析,生态足迹,虚拟水计算,决策分析,SWOT分析和3S等技术方法,在大气与海域环境容量、生态功能分区、环境发展战略、生态承载力等方面大量理论研究的基础上,提出了包括大气环境规划、水环境规划、声环境规划、固体废物处置规划、核与辐射污染控制规划、工业布局与结构调整规划、自然生态系统规划、农村环境保护规划、环境风险防范以及环境管理能力建设规划等10个方面的规划.《规划》通过全域谋划、统筹规划,有步骤、分阶段地解决制约经济发展和群众关注的环境问题,有效协调生态保护区和经济开发区的关系,最终实现"社会-经济-资源-环境"的可持续发展.

关键词：环境总体规划内涵战略地位实施思路