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基于PID参数整定的线性自抗扰控制参数整定

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控制与决策 2021年第7期36卷 1592-1600页

作者：韩文杰谭文华北电力大学控制与计算机工程学院北京102206

线性自抗扰控制(linear active disturbance rejection control,LADRC)是不依赖于被控对象的数学模型,在工业过程中具有极大的应用前景,LADRC参数整定是其在工业过程中能否应用的重要环节.鉴于实际工业控制中大都采用PID控制器,通过对二... 详细信息

线性自抗扰控制(linear active disturbance rejection control,LADRC)是不依赖于被控对象的数学模型,在工业过程中具有极大的应用前景,LADRC参数整定是其在工业过程中能否应用的重要环节.鉴于实际工业控制中大都采用PID控制器,通过对二阶LADRC结构与其状态观测器的传递函数进行分析,得到二阶LADRC与PID控制器具有较强的联系,且LADRC比PID有着更好的控制性能.提出一种通过现有PID参数直接得到LADRC参数初始值的方法,以达到更好的控制性能,并基于一阶惯性加时延模型,得到将现有PID整定方法转化为二阶线性自抗扰控制参数整定方法.最后通过基准系统仿真表明所提出方法的有效性.

关键词：线性自抗扰控制 PID控制参数整定抗干扰性能一阶惯性加时延模型基准系统

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隧道衬砌防脱空预警监控新技术研究与应用

现代隧道技术 2020年第3期57卷 199-203页

作者：谭文中铁十一局集团有限公司武汉430061

隧道衬砌空洞是常见的质量缺陷问题,对铁路运营安全危害极大。文章分析了造成隧道拱顶脱空的主要原因,着重研究了用于防治隧道衬砌脱空的智能监测技术、视频监控系统,并通过智能预警技术进一步优化带模注浆施工技术。在京沈高铁北京段... 详细信息

隧道衬砌空洞是常见的质量缺陷问题,对铁路运营安全危害极大。文章分析了造成隧道拱顶脱空的主要原因,着重研究了用于防治隧道衬砌脱空的智能监测技术、视频监控系统,并通过智能预警技术进一步优化带模注浆施工技术。在京沈高铁北京段梨花顶隧道的成功应用效果表明,新型防脱空预警技术是一种较好的监控措施和监督管理手段,能从根本上解决隧道拱顶衬砌空洞问题,同时又降低带模注浆量,节省成本,提升经济效益。

关键词：隧道衬砌空洞智能监测防治技术拱顶带模注浆

Young Zhou Enlai in Tianjin

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China News Release 2024年第1期 62-65页

作者： Xu Xing tan wen the Zhou Enlai Research Center of Nankai University Nankai University's Zhou Enlai School of Government

January 8,2024,marks the 48th anniversary of the passing of Premier Zhou Enlai(1898–1976).Zhou was a great Marxist,a prominent proletarian revolutionary,politician,military strategist and diplomat.“Every time we mention Zhou’s name,we feel warm and proud,”Chinese President Xi Jinping said,praising his great contribution and lofty spirit which has been enshrined in the hearts of the Chinese people and those around the world who pursue peace and justice.

关键词： peace anniversary passing

The embedded financial governance system based on COSO framework A new method of integration

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Journal of Modern Accounting and Auditing 2009年第11期5卷 28-37页

作者： tan wen-hao LIU Hong Department of Accounting College of Science and Technology Nanchang University Nanchang 330029 China School of Foreign Languages and Culture Nanjing Normal University Nanjing 210097 China

The global financial crisis is spreading at an alarming rate across the world. The speed of the spreading and its tremendous impacts to economic is unprecedented in half a century. Through researching its impacts to finance, the authors can clearly find that to a large extent most enterprises went bankrupt and closed down because of the weak financial governance system and lack of effective control to internal financial operation Based on this background, the authors analyzed the problems of the traditional financial governance, and tried to find solutions. Applying the concept of COSO （The Committee of Sponsoring Organizations of The National Commission of Fraudulent Financial Reporting） framework into the financial governance system, the authors can reconstruct the embedded financial governance system based on COSO framework, and better control the company＇s financial activities. In this way, the enterprise can effectively improve its management level and operational efficiency, and promote its sound and sustainable development.

关键词： COSO framework the embedded financial governance risk management

Effect of Cobalt-Doped Framework on Formation of Todorokite from Layered Manganese Oxides with Mg^(2+)/Co^(2+) Ions as Template

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Pedosphere 2011年第6期21卷 730-737页

作者： CUI Hao-Jie LIU Fan tan wen-Feng FENG Xiong-Han Institute of Urban Environment Chinese Academy of Sciences Xiamen 361021 （China） Key Laboratory of Subtropical Agricultural Resources and Environment Ministry of Agriculture Huazhong Agricultural University Wuhan 430070 （China）

Cobalt （Co） exists in significant quantities in naturally occurring manganese （Mn） oxides and alters the growth of Mn oxide crystals. Four-layered Mn oxides, Na-buserite （Na-bus） and three Co-doped Na-buserite samples prepared from oxidation of Mn（OH）2 with 5%, 10%, and 20% Co/（Mn ＋ Co） molar ratios （5Co-Na-bus, 10Co-Na-bus, and 20Co-Na-bus）, were used to prepare todorokite, a common Mn oxide on the Earth＇s surface, using Mg2＋/Co2＋ ions as a template. The results showed that todorokites could be obtained by reflux treatment of Mg2＋-exchanged non-doped Na-buserite and three Co-doped Na-buserites at atmospheric pressure. However, the formation of todorokites was prohibited by reflux treatment of Co2＋-exchanged Na-bus, 5Co-Na-bus, and 10Co-Na-bus samples. Instead, todorokite was obtained by the reflux treatment of Co2＋-exchanged 20Co-Na-bus samples under atmospheric pressure. X-ray photoelectron spectroscopy analysis showed that doped Co existed as Co3＋ in the MnOs layers of doped Na-buserites. The amount of substituted Co3＋ in the MnO6 layers may play a key role in the conversion of buserite to todorokite using Co2＋ ions as a template.

关键词： Mn oxide Na-buserite reflux treatment transformation tunnel structure

Development of composite PLGA microspheres containing exenatide-encapsulated lecithin nanoparticles for sustained drug release

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Asian Journal of Pharmaceutical Sciences 2020年第3期15卷 347-355页

作者： Ni Dong Chune Zhu Junhuang Jiang Di Huang Xing Li Guilan Quan Yang Liu wen tan Xin Pan Chuanbin Wu School of Pharmaceutical Sciences Sun Yat-sen UniversityGuangzhou 510006China Institute of Biomedical and Pharmaceutical Sciences Guangdong University of TechnologyGuangzhou 510006China Shenyang Pharmaceutical University Benxi 117004China College of Pharmacy Chongqing Medical and Pharmaceutical CollegeChongqing 401331China

This study aimed to prepare poly(D, L-lactic-co-glycolic acid) microspheres(PLGA-Ms)by a modified solid-in-oil-in-water(S/O/W) multi-emulsion technique in order to achieve sustained release with reduced initial burst and maintain efficient drug concentration for a prolonged period of time. Composite PLGA microspheres containing exenatideencapsulated lecithin nanoparticles(Ex-NPs-PLGA-Ms) were obtained by initial fabrication of exenatide-loaded lecithin nanoparticles(Ex-NPs) via the alcohol injection method,followed by encapsulation of Ex-NPs into PLGA microspheres. Compared to Ms prepared by the conventional water-in-oil-in-water(W/O/W) technique(Ex-PLGA-Ms), Ex-NPs-PLGAMs showed a more uniform particle size distribution, reduced initial burst release, and sustained release for over 60 d in vitro. Cytotoxicity studies showed that Ms prepared by both techniques had superior biocompatibility without causing any detectable *** pharmacokinetic studies, the effective drug concentration was maintained for over 30 d following a single subcutaneous injection of two types of Ms formulation in rats, potentially prolonging the therapeutic action of Ex. In addition, administration of Ex-NPs-PLGA-Ms resulted in a more smooth plasma concentration-time profile with a higher area under the curve(AUC) compared to that of Ex-PLGA-Ms. Overall, Ex-NPs-PLGA-Ms prepared by the novel S/O/W method could be a promising sustained drug release system with reduced initial burst release and prolonged therapeutic efficacy.

关键词： Microspheres PLGA Peptides Lipid nanoparticles Sustained drug release

Catalytic production of high-energy-density spiro polycyclic jet fuel with biomass derivatives

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Journal of Energy Chemistry 2025年第2期101卷 760-768页

作者： wen-Jing Zhang Yan-Cheng Hu Yan-Hong tan Jia Li Ning Li Jing-Pei Cao School of Chemical Engineering and Technology China University of Mining and Technology CAS Key Laboratory of Science and Technology on Applied Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences

High-energy-density（HED） fuel（*** used JP-10 and RJ-4）,featuring compact 3D polycyclic structure with high strain,is of critical importance for volume-limited military aircraft,since their high density and combustion heat can provide more propulsion *** reduce the reliance on petroleum source,it is highly desirable to develop renewable alternatives for the production of strained polycyclic HED fuel,but which remains a big challenge because of the inaccessibility caused by the high strain,We herein demonstrate a three-step catalytic route towards highly strained C17and C18spirofuel with biomass *** process includes catalytic aldol condensation of renewable cyclohexanone/cyclopentanone with benzaldehyde,catalytic spiro Diels-Alder（D-A） reaction of aldol adduct with isoprene,and catalytic *** key spiro D-A reaction is enabled by the catalysis of heterogeneous Lewis acidic ionic *** chloroaluminate IL,formed by benign urea and AICl3,exhibits good catalytic performance and reusability for this *** eventual hydrodeoxygenation（HDO）over Pd/C and H-Y produces strained tricyclic spirofuel with density>0.93 g/mL,combustion heat>41 MJ/L and freezing point <-40℃,which are better than the properties of tactical fuel ***,it is anticipated that the as-prepared renewable fuels have the potential to replace traditional petroleum-derived HED fuels.

关键词： Biomass derivatives Cycloaddition High-energy-density Lewis acidic ionic liquid Spiro polycyclic fuel

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水轮机负荷频率控制系统的线性自抗扰整定

电机与控制学报 2019年第1期23卷 117-124页

作者：张彬文谭文李健华北电力大学控制与计算机工程学院北京102206

目前LADRC参数整定常采用带宽法,对非最小相位系统控制有一定局限。针对这一问题,利用广义自抗扰控制(GADRC)来整定LADRC参数。该方法借鉴常规ADRC带宽整定法的思路,利用模型信息,适用于所有线性系统的ADRC参数整定。为了克服得到的LADR... 详细信息

目前LADRC参数整定常采用带宽法,对非最小相位系统控制有一定局限。针对这一问题,利用广义自抗扰控制(GADRC)来整定LADRC参数。该方法借鉴常规ADRC带宽整定法的思路,利用模型信息,适用于所有线性系统的ADRC参数整定。为了克服得到的LADRC控制器阶数较高的问题,采用频域下的控制器降阶,得到低阶LADRC。所提整定方法不受控制器和观测器带宽配置的限制,便于工程实现。将该方法应用于有自平衡能力和无自平衡能力的水轮机负荷频率控制系统的设计,仿真结果表明,由GADRC整定LADRC可以获得较好的控制性能且系统抗干扰能力好,鲁棒性强。

关键词：负荷频率控制水轮机线性自抗扰控制控制器频域降阶带宽法

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双质量弹簧基准问题自抗扰控制研究

控制理论与应用 2020年第4期37卷 933-940页

作者：李健张彬文谭文华北电力大学控制与计算机工程学院北京102206

本文研究了自抗扰控制(ADRC)方法在双质量弹簧基准问题的应用.传统的自抗扰控制方法倾向于使用高增益控制来抑制扰动和模型不确定性,但是对于双质量弹簧基准问题,高增益在评分中受到较大惩罚,而且对于模型参数变化没有足够的鲁棒性.为... 详细信息

本文研究了自抗扰控制(ADRC)方法在双质量弹簧基准问题的应用.传统的自抗扰控制方法倾向于使用高增益控制来抑制扰动和模型不确定性,但是对于双质量弹簧基准问题,高增益在评分中受到较大惩罚,而且对于模型参数变化没有足够的鲁棒性.为解决这一问题,本文对ADRC设计提出了两种改进方案.首先,为了减小控制信号的幅度,将扩张状态观测器(ESO)的一个极点配置在原点.其次,采用阻尼比来调整带宽.结果表明,所提出的ADRC设计可以很好地解决双质量弹簧基准系统的控制问题.

关键词：自抗扰控制双质量弹簧基准问题鲁棒控制带宽