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An Energy-based Nonlinear Coupling Control for Offshore Ship-mounted Cranes

International Journal of Automation and computing 2018年第5期15卷 570-581页

作者： Yu-zhe Qian Yong-Chun fang Tong Yang Institute of Robotics and Automatic Information System Nankai University Tianjin Key Laboratory of Intelligent Robotics Nankai University

This paper proposes a novel nonlinear energy-based coupling control for an underactuated offshore ship-mounted crane,which guarantees both precise trolley positioning and payload swing suppressing performances under external sea wave disturbance. In addition to having such typical nonlinear underactuated property, as it is well known, an offshore ship-mounted crane also suffers from much unexpected persistent disturbances induced by sea waves or currents, which, essentially different from an overhead crane fixed on land, cause much difficulty in modeling and controller design. Inspired by the desire to achieve appropriate control performance against those challenging factors, in this paper, through carefully analyzing the inherent mechanism of the nonlinear dynamics, we first construct a new composite signal to enhance the coupling behavior of the trolley motion as well as the payload swing in the presence of ship′s roll motion disturbance. Based on which, an energy-based coupling control law is presented to achieve asymptotic stability of the crane control system′s equilibrium point. Without any linearization of the complex nonlinear dynamics, unlike traditional feedback controllers, the proposed control law takes a much simpler structure independent of the system parameters. To support the theoretical derivations and to further verify the actual control performance, Lyapunov-based mathematical analysis as well as numerical simulation/experimental results are carried out, which clarify the feasibility and superior performance of the proposed method over complicated disturbances.

关键词： Energy-based control offshore ship-mounted cranes Lyapunov methods underactuated nonlinear control systems.

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青藏高原南部湖泊记录的晚全新世植被演化过程

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第四纪研究 2024年第3期44卷 742-754页

作者：简安璟李昀卿刘斯瑶陈美娇曹维予孙喆侯居峙田芳首都师范大学资源环境与旅游学院北京100048 四川师范大学地理与资源科学学院四川成都610066 中国科学院青藏高原研究所古生态与人类适应团队北京100101 中国科学院青藏高原研究所青藏高原地球系统与资源环境全国重点实验室北京100101

青藏高原是我国重要的生态安全屏障,其生态系统安全是实现高原可持续发展的基础。植被覆盖度是评价植被状况的重要指标,研究其演变过程及机制具有重要意义。本研究选择青藏高原南部昂仁金错沉积岩芯(长120 cm)作为研究对象,基于可靠的AM... 详细信息

青藏高原是我国重要的生态安全屏障,其生态系统安全是实现高原可持续发展的基础。植被覆盖度是评价植被状况的重要指标,研究其演变过程及机制具有重要意义。本研究选择青藏高原南部昂仁金错沉积岩芯(长120 cm)作为研究对象,基于可靠的AMS ^(14)C年代序列和孢粉记录,研究距今3600年以来的植被变化过程;选用青藏高原南部614个现代孢粉和植被覆盖度数据并基于现代类比法(MAT)构建校准集,交叉检验表明模型可靠性较高(R^(2)=0.71,RMSE=8.51%),可用于定量重建植被覆盖度演化过程。研究结果表明,昂仁金错晚全新世沉积物孢粉组合以草本植物花粉为主,主要包括莎草科、蒿属、禾本科、毛茛科等花粉类型。3600~850 cal.a B.P.期间,莎草科花粉占优势,表明湖泊周围发育了植被覆盖度较高的高寒草甸,气候较为湿润;而850 cal.a B.P.以来,蒿属花粉含量不断增加,表明植被向高寒草原转变,覆盖度显著降低。经区域多记录对比发现,该时期植被类型的转变为区域性现象,应代表了印度夏季风减弱和气候变干的整体趋势。

关键词：昂仁金错孢粉植被覆盖度现代类比法

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发泡剂和增硬树脂对轻质天然橡胶材料性能的影响

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特种橡胶制品 2024年第1期45卷 1-5页

作者：方兆森翟俊学刘浩牛明哲陈峰青岛科技大学橡塑材料与工程教育部重点实验室青岛266042

采用均匀设计法,考察了发泡剂和增硬树脂对轻质天然橡胶材料性能的影响。结果表明,发泡剂N,N′-二亚硝基五亚甲基四胺(H)和增硬树脂(P1)用量变化对NR密度和拉伸强度等有显著影响。增大发泡剂H和增硬树脂P用量,发泡压力增大,硫化起步提前... 详细信息

采用均匀设计法,考察了发泡剂和增硬树脂对轻质天然橡胶材料性能的影响。结果表明,发泡剂N,N′-二亚硝基五亚甲基四胺(H)和增硬树脂(P1)用量变化对NR密度和拉伸强度等有显著影响。增大发泡剂H和增硬树脂P用量,发泡压力增大,硫化起步提前,最高硫化扭矩先增大后减小,拉伸强度和密度均呈线性变化。与单一发泡剂H胶料相比,发泡剂偶氮二甲酰胺(AC)/发泡剂H并用胶料硬度、密度、撕裂强度和定伸应力均较高,发泡材料孔径较小;发泡剂4,4′-氧代双苯磺酰肼(OBSH)/发泡剂H并用胶料密度最小,拉伸强度最大。

关键词：天然橡胶发泡增硬配方设计

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Three-dimensional fluorescence spectral characterization of soil dissolved organic matters in the fluctuating water-level zone of Kai County,Three Gorges Reservoir

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Frontiers of Environmental Science & Engineering 2011年第3期5卷 426-434页

作者： fang fang Yan YANG Jinsong GUO Hong ZHOU Chuan FU zhe LI Key Laboratory of Three Gorges Reservoir Region’s Eco-Environment of Ministry of Education Chongqing UniversityChongqing 400045China

Three-dimensional fluorescence spectroscopy was used to investigate the fluorescent properties of soil dissolved organic matter(DOM)in the water-levelfluctuation zone(WLFZ)of Kai County,Three Gorges Reservoir(TGR).Most of the soil DOM analyzed in this study was found to contain four fluorescence *** A and C represent humic-like fluorescence,whereas peaks B and D represent tryptophan-like *** E and F,which represent tyrosine-like fluorescence,only appeared in certain *** humus was the main source of DOM in soil,and higher concentration of soil DOM was found in the exposed soil than submerged *** to the peaks A and B,the fluorescence intensities of peaks C and D were strongly influenced by the fluctuating water *** of fluorescence intensities of different peaks in soil DOM showed that WLFZ soil was not contaminated *** DOM contained at least two types of humic-like fluorescence groups and two types of protein-like fluorescence *** proportion of the content of peak A in soil organic matter was quite *** soil DOM in exposed soil had relatively high humification and aromaticity,and periodic submerging and exposure of soil had an impact on the humification of soil DOM.

关键词： water-level-fluctuation zone(WLFZ) soil dissolved organic matter(DOM) three-dimensional fluorescence spectra

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Isolation and bioactivity screening of soy isoflavones from soybean glycolipids identifies daidzin as a promising anti-inflammatory agent

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Traditional Medicine Research 2024年第3期9卷 1-9页

作者： Xiao-Chuan fang Xue-Mei He Yuan-Ru zheng Wen Li Tang-Jia Yang Jing-Tao Yu Jun-Le Li Zi-zhe Cai Yong Wang Lin-Zhong Yu Jun-Shan Liu Third Level Research Laboratory of State Administration of Traditional Chinese Medicine Guangdong Provincial Key Laboratory of Chinese Medicine PharmaceuticsSchool of Traditional Chinese MedicineSouthern Medical UniversityGuangzhou 510515China Guangdong Saskatchewan Oilseed Joint Laboratory Department of Food Science and EngineeringJinan UniversityGuangzhou 510632China Institute of Biomedical Engineering College of Life Science and TechnologyJinan UniversityGuangzhou 510632China Department of Pharmacy Zhujiang HospitalSouthern Medical UniversityGuangzhou 510515China

Background:Soybean has long been utilized in the realm of traditional Chinese *** of its extracts,soybean glycolipids,serves as a vital by-product of soybean oil refining,but its chemical composition and pharmacological potential have yet to be fully ***:In this study,the chemical components were isolated,and the inhibitory effects of these isolates were explored in different zebrafish inflammatory models by survival rate,Histological examination assay and quantitative Real-time PCR *** cytotoxicity of daidzin in RAW264.7 cells was evaluated by cell viability assay,and the effect of daidzin on the release of inflammatory cytokines in RAW264.7 cells was detected by enzyme linked immunosorbent assay(ELISA).Western blotting,immunofluorescence assay and alpha7 nicotinic acetylcholine receptors siRNA transfection assay were used to further explore the anti-inflammatory mechanism of ***:Four compounds(verticilloside,soya-cerebroside I,soya-cerebroside II and daidzin)were firstly isolated from the soybean glycolipids,among which verticilloside and daidzin inhibited the lipopolysaccharide,CuSO4-and tail cut-stimulated zebrafish ***,daidzin exhibited anti-inflammatory activities by increasing the survival rate,alleviating the inflammatory cells infiltration,and down-regulating the expression of pro-inflammatory cytokines and nuclear factor kappa-B,NF-kappa-B inhibitor alpha,and signal transducer and activator of transcription3 in ***,daidzin decreased the secretion of IL-6 and TNF-α,inhibited the nuclear translocations of nuclear factor kappa-B p65 and p-signal transducer and activator of transcription3 as well as the NF-kappa-B inhibitor alpha phosphorylation at Ser32 in RAW 264.7 *** importantly,it elevated the expression level of alpha7 nicotinic acetylcholine receptors in both zebrafish and RAW 264.7 cells,and the inhibitory effect of daidzin was attenuated after the addition of alpha7 ni

关键词： soybean daidzin anti-inflammation zebrafish α7nAchR

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Seasonal variation of nitrogen and phosphorus in Xiaojiang River-A tributary of the Three Gorges Reservoir

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Frontiers of Environmental Science & Engineering 2009年第3期3卷 334-340页

作者： zhe LI Jinsong GUO Man LONG fang fang Jinping SHENG Hong ZHOU Faculty of Urban Construction&Environmental Engineering Chongqing UniversityChongqing 400045China

A yearlong monitoring program in the backwater area of Xiaojiang River(XBA)was launched in order to investigate the eutrophication of backwater areas in tributaries of the Yangtze River in the Three Gorges Reservoir(TGR)in China,starting after the impoundment water level of the TGR reached 156 *** March 2007 to March 2008,the average concentration of total nitrogen(TN)and total phosphorus(TP)were(1553484)μg·L^(–1)and(6231)μg·L^(–1),*** mean value of chlorophyll was(9.070.91)μg·L^(–1).The trophic level of XBA was meso-eutrophic,while the general nutrient limitation was *** results indicated that XBA has a strong ability to purify itself and has non-point source pollution from terrestrial *** variation of TN/TP ratio was caused by a variation in TN rather than in TP when TN/TPming the nitrogen deficit under a low TN/TP *** TN/TP≥22,the variation of TP affected the TN/TP ratio more significantly than *** increase of TP in XBA was caused mainly by particulate phosphorus,which could originate from a non-point source as adsorptive inorganic forms after heavy rainfall and surface *** increase in the river’s flow could also contribute to an unstable environment for the growth of phytoplankton.

关键词： Three Gorges Reservoir eutrophication nitrogen phosphorus seasonal variation chlorophyll

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依达拉奉与尼莫地平联合微创颅内血肿清除术治疗高血压脑出血的效果分析

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中国现代药物应用 2024年第19期18卷 79-82页

作者：方奕儒王煜喆黄焱漳州市医院 363000

目的探究高血压脑出血患者在微创颅内血肿清除术治疗期间联合依达拉奉、尼莫地平治疗的临床效果。方法100例高血压脑出血患者,按照随机的分组原则分为观察组和对照组,各50例。对照组实施微创颅内血肿清除术,观察组在对照组基础上联合依... 详细信息

目的探究高血压脑出血患者在微创颅内血肿清除术治疗期间联合依达拉奉、尼莫地平治疗的临床效果。方法100例高血压脑出血患者,按照随机的分组原则分为观察组和对照组,各50例。对照组实施微创颅内血肿清除术,观察组在对照组基础上联合依达拉奉注射液与尼莫地平注射液进行治疗。比较两组患者治疗前后的血清炎性因子、凝血功能指标、血肿体积以及预后情况。结果治疗后,两组患者超敏C反应蛋白(hs-CRP)、白细胞介素6(IL-6)、肿瘤坏死因子-α(TNF-α)水平均低于治疗前,且观察组患者hs-CRP(13.93±3.25)mg/L、IL-6(34.96±1.48)pg/ml、TNF-α(9.63±0.86)pg/ml均低于对照组的(19.78±4.17)mg/L、(47.64±1.59)pg/ml、(13.52±3.19)pg/ml,具有显著差异(P<0.05)。治疗后,两组患者D二聚体(D-D)均低于治疗前,凝血酶原时间(PT)、活化部分凝血活酶时间(APTT)均短于治疗前,且观察组的D-D(0.82±0.21)mg/L明显低于对照组的(1.39±0.39)mg/L,PT(12.93±0.98)s、APPT(29.63±6.16)s均短于对照组的(14.25±0.96)、(32.52±5.24)s,具有显著差异(P<0.05)。治疗后,观察组血肿体积(3.64±0.31)ml小于对照组的(3.86±0.20)ml,具有显著差异(P<0.05)。观察组预后优良率90.0%高于对照组的52.0%,具有显著差异(P<0.05)。结论高血压脑出血患者实施微创颅内血肿清除术治疗期间联合应用依达拉奉、尼莫地平,可改善患者病症,缩小血肿体积,值得临床借鉴。

关键词：依达拉奉尼莫地平微创颅内血肿清除术高血压脑出血

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高校辅导员对大学生进行学习指导和学习心理调节的策略分析

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当代教研论丛 2024年第7期10卷 70-74页

作者：王华芳姚晰哲山西工程技术学院山西阳泉045000

高校辅导员作为学生工作的主要实施者,肩负着对大学生进行学习指导和心理调节的重要职责。随着当前大学生学习压力和心理问题的日益凸显,探索有效的对策和方法,提高辅导员的工作效能,对于促进大学生全面发展具有重要意义。文章以山西工... 详细信息

高校辅导员作为学生工作的主要实施者,肩负着对大学生进行学习指导和心理调节的重要职责。随着当前大学生学习压力和心理问题的日益凸显,探索有效的对策和方法,提高辅导员的工作效能,对于促进大学生全面发展具有重要意义。文章以山西工程技术学院学生为研究对象,基于学生在学习的认知理解、情绪意志和行为实践方面的现状,从辅导员视角提出了应对策略,以期为提升辅导员工作效果提供参考与借鉴。

关键词：大学生学习心理认知调整情绪调节行为指导

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Design, Synthesis and in vitro Evaluation of Thiazole Derivatives of Ibuprofen as Cyclooxygenase-2 Inhibitors

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Chinese Chemical Letters 2006年第3期17卷 325-328页

作者： Chang Bin GUO zhe Feng CAI Zong Ru GUO Zhi Qiang FENG Feng ming CHU Gui-fang CHENG Feng ming CHU Gui Fang CHENG Institute of Materia Medica Chinese Academy of Medical Science and Peking Union Medical College Beijing 100050

A series of thiazole derivatives of ibuprofen, as cyclooxygenase-2 Inhibitors, were designed, synthesized and in vitro evaluated.

关键词： Cyclooxygenase-2 (COX-2) inhibitor ibuprofen thiazole derivative.

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低氧诱导间充质干细胞外泌体通过改变M1/M2巨噬细胞极化减少椎间盘细胞凋亡和衰老

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中华实验外科杂志 2024年第4期41卷 803-806页

作者：李放姜帆马新妞杜哲北京大学人民医院创伤救治中心北京100044

目的观察低氧预处理是否可以提高间充质干细胞外泌体治疗椎间盘退变的效果,探讨外泌体和巨噬细胞极化的机制。方法建立外泌体、巨噬细胞、髓核细胞的非接触共培养系统,分为对照组、常氧组及低氧组,对照组为巨噬细胞+脂多糖(LPS)或巨噬... 详细信息

目的观察低氧预处理是否可以提高间充质干细胞外泌体治疗椎间盘退变的效果,探讨外泌体和巨噬细胞极化的机制。方法建立外泌体、巨噬细胞、髓核细胞的非接触共培养系统,分为对照组、常氧组及低氧组,对照组为巨噬细胞+脂多糖(LPS)或巨噬细胞和髓核细胞共培养体系;常氧组为添加常氧外泌体的共培养体系;低氧组是添加低氧诱导外泌体的共培养体系。通过定量实时聚合酶链反应、流式细胞术、β-半乳糖苷酶染色、免疫荧光染色测定常氧外泌体/低氧诱导外泌体对巨噬细胞极化的影响,对髓核细胞凋亡及衰老的影响。组间计量数据比较采用t检验。结果低氧组CD86的表达水平显著低于常氧组(2.78±0.31比7.00±0.51,t=8.627,P<0.05),CD163表达水平显著高于常氧组(19.01±0.38比15.54±0.44,t=9.499,P<0.05)。流式细胞术显示,低氧组髓核细胞凋亡率显著低于常氧组(4.44±0.40比11.16±0.50,t=14.351,P<0.05)。β-半乳糖苷酶染色结果显示,低氧组髓核细胞衰老率显著低于常氧组(49.75±1.63比59.71±1.63,t=4.425,P<0.05)。免疫组织化学染色证实,低氧组可增加合成基因COL2(1.35±0.03比1.03±0.05,t=6.500,P<0.05)及蛋白聚糖(ACAN)的表达(1.66±0.05比1.03±0.05,t=13.141,P<0.05),降解基因基质金属蛋白酶(MMP)-13(0.80±0.04比1.00±0.05,t=5.496,P<0.05)及ADAMTS5的表达低于常氧组(0.84±0.02比1.00±0.05,t=6.723,P<0.05)。结论间充质干细胞外泌体在体外低氧条件下减少细胞凋亡和衰老,可能是通过M1/M2巨噬细胞的极化。

关键词：间充质干细胞外泌体巨噬细胞极化椎间盘退变

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