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期刊论文 132

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关键词

植物生长调节剂 4

三十烷醇 3

单边直线感应电机 2

线性规划 2

2R-1C模型;嵌入式系统;参数估计;非迭代方法;二次型 1

CPLEX 1

FLTD型脉冲加速器 1

H∞控制;零和动态博弈;强化学习;自适应动态规划;极小极大Q-学习;策略迭代 1

Lagrange方程 1

MIMO雷达;波形设计;谱分解;分式二次约束二次规划 1

PCI总线 1

TA乳粉 1

Weibull分布杂波 1

ZMNL 1

中断模型;k-可靠性;对偶;线性规划松弛;互补松弛型 1

二维线性鉴别分析 1

人脸建模 1

人脸识别 1

仿真 1

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A linear quadratic regulator control of a stand-alone PEM fuel cell power plant

Amar BENAISSA, Boualaga RABHI, Ammar MOUSSI, Dahmani AISSA

《能源前沿(英文)》 2014年 第8卷 第1期   页码 62-72 doi: 10.1007/s11708-013-0291-5

摘要: This paper introduces a technique based on linear quadratic regulator (LQR) to control the output voltage at the load point versus load variation from a stand-alone proton exchange membrane (PEM) fuel cell power plant (FCPP) for a group housing use. The controller modifies the optimal gains by minimizing a cost function, and the phase angle of the AC output voltage to control the active and reactive power output from an FCPP to match the terminal load. The control actions are based on feedback signals from the terminal load, output voltage and fuel cell feedback current. The topology chosen for the simulation consists of a 45 kW proton exchange membrane fuel cell (PEMFC), boost type DC/DC converter, a three-phase DC/AC inverter followed by an LC filter. Simulation results show that the proposed control strategy operated at low commutation frequency (2 kHz) offers good performances versus load variations with low total harmonic distortions (THD) , which is very useful for high power applications.

关键词: modeling of proton exchange membrane fuel cell (PEMFC)     controlling of PEMFC     linear quadratic regulator (LQR)     DC/DC converter     DC/AC inverter    

Load shedding scheme for the two-area system with linear quadratic regulator

D. TYAGI, Ashwani KUMAR, Saurabh CHANANA

《能源前沿(英文)》 2013年 第7卷 第1期   页码 90-102 doi: 10.1007/s11708-012-0224-8

摘要: The power system is prone to many emergency conditions which may lead to emergency state of operation with decay in the system frequency. The dramatic change in the frequency can result in cascaded failure of the system. In order to avoid power system collapse, load shedding (LS) schemes are adopted with the optimal amount of load shed. This paper proposed a methodology in a two-area thermal-thermal system for finding the required amount of load to be shed for setting the frequency of the system within minimum allowable limits. The LS steps have been obtained based on the rate of change of frequency with the increase in load in steps. A systematic study has been conducted for three scenarios: the scheme with a conventional integral controller; the scheme with a linear quadratic regulator (LQR); and the scheme with an LQR and superconducting magnetic energy storage devices (SMES). A comparison of the results has been presented on the two-area system.

关键词: critical load     frequency response     load shedding (LS)     multi-area system     rate of change of frequency     linear quadratic regulator (LQR)     superconducting magnetic energy storage devices (SMES)    

基于随机鲁棒性分析的吸气式高超声速飞行器线性二次调节器设计 Article

Lin CAO, Shuo TANG, Dong ZHANG

《信息与电子工程前沿(英文)》 2017年 第18卷 第7期   页码 882-897 doi: 10.1631/FITEE.1601363

摘要: 本文介绍了一种改进的基于随机鲁棒性分析的线性二次调节器(linear-quadratic regulator, LQR)设计方法,用于AHV的纵向飞行控制器设计。首先,应用输入输出反馈线性化技术设计LQR控制器。其次,基于系统参数的不确定性,将系统鲁棒性表征为满足稳定性与设计指标要求的概率,并构建系统鲁棒性与LQR参数之间的映射关系。为了实现系统鲁棒性最大化的目标,提出一种全新的混合粒子群优化算法对LQR的控制参数进行寻优计算。在优化迭代的过程中,使用切诺夫边界理论确定蒙特卡洛估计的随机样本量。最后,仿真结果表明该优化算法可以高效地获取满足设计要求的LQR控制参数最优解。

关键词: 吸气式高超声速飞行器;随机鲁棒性分析;二次线性调节器;粒子群优化;改进混合粒子群算法    

铰接车辆的主动转向控制策略研究 Article

Kyong-il KIM,Hsin GUAN,Bo WANG,Rui GUO,Fan LIANG

《信息与电子工程前沿(英文)》 2016年 第17卷 第6期   页码 576-586 doi: 10.1631/FITEE.1500211

摘要: 为了提高铰接车辆的机动性及高速稳定性,基于线性二次型最优控制理论提出了一种用于拖车和挂车的主动转向控制策略。首先建立了3自由度的带挂车主动转向的拖挂车简化模型。运用基于模拟退火的粒子群优化算法对简化模型在特定速度和方向盘角度下的车辆关键参数进行辨识,简化模型的参数可通过当前车辆工况查表和插值获得。仿真结果表明简化模型的输出结果与TruckSim一致性较好,这样简化模型可准确为控制器提供理想的横摆角速度。设计了基于线性二次型最优控制的主动转向控制器。控制器时刻跟踪理想的横摆角速度并同时尽量降低拖车和挂车的质心侧偏角。最后,基于TruckSim-Simulink联合仿真分别进行了低速和高速试验。仿真试验结果表明主动转向控制策略能显著改善拖挂车低速的机动性和高速稳定性。控制策略不仅适用于弯度不大的转弯路况,还适用于急转弯路况。

关键词: 铰接车辆;急转弯;侧向稳定性;线性二次型控制    

Linear quadratic optimal controller for cable-driven parallel robots

Saeed ABDOLSHAH,Erfan SHOJAEI BARJUEI

《机械工程前沿(英文)》 2015年 第10卷 第4期   页码 344-351 doi: 10.1007/s11465-015-0364-8

摘要:

In recent years, various cable-driven parallel robots have been investigated for their advantages, such as low structural weight, high acceleration, and large workspace, over serial and conventional parallel systems. However, the use of cables lowers the stiffness of these robots, which in turn may decrease motion accuracy. A linear quadratic (LQ) optimal controller can provide all the states of a system for the feedback, such as position and velocity. Thus, the application of such an optimal controller in cable-driven parallel robots can result in more efficient and accurate motion compared to the performance of classical controllers such as the proportional-integral-derivative controller. This paper presents an approach to apply the LQ optimal controller on cable-driven parallel robots. To employ the optimal control theory, the static and dynamic modeling of a 3-DOF planar cable-driven parallel robot (Feriba-3) is developed. The synthesis of the LQ optimal control is described, and the significant experimental results are presented and discussed.

关键词: accuracy     cable-driven parallel robot     linear quadratic optimal control    

基于线性二次最优化的多智能体编队控制

Chang-bin Yu, Yin-qiu Wang, Jin-liang Shao,brad.yu@anu.edu.au,wh6508@gmail.com,jinliangshao@126.com

《信息与电子工程前沿(英文)》 2016年 第17卷 第2期   页码 96-109 doi: 10.1631/FITEE.1500490

摘要: 方法:应用代数图论以及矩阵理论的相关知识,针对无物理耦合的多智能体系统,通过求解代数里卡蒂方程,设计智能体之间的网络连接拓扑以及局部反馈矩阵,保证多智能体系统在完成编队的同时相应的LQR指标最优。针对有物理耦合的多智能体系统,同样通过求解代数里卡蒂方程,得到相应的网络连接拓扑以及局部反馈矩阵,保证多智能体系统在完成编队的基础上使相应的LQR指标最优;针对有物理耦合但无法设计网络拓扑的多智能体系统

关键词: 线性二次最优;编队控制;代数里卡蒂方程;最优控制;多智能体系统    

New decentralized control technique based on substructure and LQG approaches

Ying LEI, Ying LIN,

《机械工程前沿(英文)》 2009年 第4卷 第4期   页码 386-392 doi: 10.1007/s11465-009-0041-x

摘要: Decentralized control is more suitable for structural control of large-scale structures. In this paper, a new decentralized control technique is proposed based on the linear quadratic Gaussian (LQG) and substructure approaches. A large-scale structure is divided into a set of smaller substructures. Each substructure is controlled by its own local controller with interaction forces at substructural interfaces, which are considered as “unknown external inputs” to the substructure concerned. An algorithm of recursive least squares estimation for the unknown excitation is proposed. A numerical example of the decentralized control of a tall building is studied to illustrate the new proposed algorithm. Simulation results show that the proposed decentralized control provides satisfactory control performance when comparing with the conventional centralized LQG control algorithm and is viable for the future structural control of large-scale structures.

关键词: substructures     decentralized control     linear quadratic Gaussian (LQG)     Kalman filter     unknown input     least-squares estimation    

Neural network control for earthquake structural vibration reduction using MRD

Khaled ZIZOUNI, Leyla FALI, Younes SADEK, Ismail Khalil BOUSSERHANE

《结构与土木工程前沿(英文)》 2019年 第13卷 第5期   页码 1171-1182 doi: 10.1007/s11709-019-0544-4

摘要: Structural safety of building particularly that are intended for exposure to strong earthquake loads are designed and equipped with high technologies of control to ensure as possible as its protection against this brutal load. One of these technologies used in the protection of structures is the semi-active control using a Magneto Rheological Damper device. But this device need an adequate controller with a robust algorithm of current or tension adjustment to operate which is further discussed in the following of this paper. In this study, a neural network controller is proposed to control the MR damper to eliminate vibrations of 3-story scaled structure exposed to Tōhoku 2011 and Boumerdès 2003 earthquakes. The proposed controller is derived from a linear quadratic controller designed to control an MR damper installed in the first floor of the structure. Equipped with a feedback law the proposed control is coupled to a clipped optimal algorithm to adapt the current tension required to the MR damper adjustment. To evaluate the performance control of the proposed design controller, two numerical simulations of the controlled structure and uncontrolled structure are illustrated and compared.

关键词: MR damper     semi-active control     earthquake vibration     neural network     linear quadratic control    

A hybrid LQR-PID control design for seismic control of buildings equipped with ATMD

Amir Hossein HEIDARI, Sadegh ETEDALI, Mohamad Reza JAVAHERI-TAFTI

《结构与土木工程前沿(英文)》 2018年 第12卷 第1期   页码 44-57 doi: 10.1007/s11709-016-0382-6

摘要: This paper presents an efficient hybrid control approach through combining the idea of proportional-integral-derivative (PID) controller and linear quadratic regulator (LQR) control algorithm. The proposed LQR-PID controller, while having the advantage of the classical PID controller, is easy to implement in seismic-excited structures. Using an optimization procedure based on a cuckoo search (CS) algorithm, the LQR-PID controller is designed for a seismic- excited structure equipped with an active tuned mass damper (ATMD). Considering four earthquakes, the performance of the proposed LQR-PID controller is evaluated. Then, the results are compared with those given by a LQR controller. The simulation results indicate that the LQR-PID performs better than the LQR controller in reduction of seismic responses of the structure in the terms of displacement and acceleration of stories of the structure.

关键词: seismic control     tuned mass dampers     cuckoo search     PID controller     LQR controller    

A new type of quadratic acceleration method

Changqing LI, Menglin LOU,

《结构与土木工程前沿(英文)》 2010年 第4卷 第3期   页码 302-310 doi: 10.1007/s11709-010-0026-1

摘要: The polynomial acceleration method for time history analysis is presented, in which accelerations between several equal neighboring time steps were assumed to be a polynomial function of time interval. With a higher order polynomial used, a higher accuracy can be obtained, but the stability field of the method becomes narrower. When stability field and computational accuracy are taken into account at the same time, the quadratic acceleration method is superior to linear and cubic acceleration methods in choosing the maximum acceptable time step size. It is also shown that the quadratic acceleration method has desirable arithmetic damp, amplitude decay rate and period elongation rate, though its conditional stability restricts its application in stiff structures.

关键词: polynomial acceleration method     convergence     stability     square acceleration method    

植物生长调节剂TA乳粉对海带产量和品质的影响

刘德盛,张群

《中国工程科学》 2000年 第2卷 第2期   页码 68-73

摘要:

目前我国海带养殖面积约1.5万hm2,年产干品27t,占世界海藻总产量的50%。三十烷醇(TA)乳粉可显著提高海带的产量和品质,海带苗经2mg/L TA浸泡2h后放养,能促进假根生长,提高保苗率,增加叶绿素、岩藻黄素含量,促进碳、氮代谢,增加干物质积累。处理比对照平均增收干品6.57t/hm2,增产率为35%。同时,海带可比对照增收碘24.24kg/hm2、褐藻胶1.665t/hm2、甘露醇1.278t/hm2。TA乳粉属国内外首创,具有无毒、高效、成本低、不变质及贮运方便等优点,已在全国海带上推广1.6万hm2,创经济效益3亿多元。

关键词: 三十烷醇     海带     植物生长调节剂    

Fibroblast growth factor 21: a novel metabolic regulator from pharmacology to physiology

null

《医学前沿(英文)》 2013年 第7卷 第1期   页码 25-30 doi: 10.1007/s11684-013-0244-8

摘要:

Fibroblast growth factor 21 (FGF21) is a member of the fibroblast growth factor family. It actually functions as endocrine hormones but does not regulate cell growth and differentiation. It is demonstrated that FGF21 acts on multiple tissue to coordinate carbohydrate and lipid metabolism, including enhancing insulin sensitivity, decreasing triglyceride concentrations, causing weight loss, ameliorating obesity-associated hyperglycemia and hyperlipidemia. Moreover, FGF21 also plays important roles in some physiological processes, such as fasting and feeding, growth hormone axis and thermogenic function of brown adipose tissue. Clinical relevance of FGF21 in humans is still unclear, and the basis and consequences of increased FGF21 in metabolic disease remain to be determined. Both the pharmacological actions and physiological roles make FGF21 attractive drug candidates for treating metabolic disease, but some questions remain to be answered. This article concentrates on recent advances in our understanding of FGF21.

关键词: FGF21     metabolism     pharmacology     physiology     clinical relevance    

Autoimmune regulator regulates autophagy in THP-1 human monocytes

Liang SHI, Li-Hua HU, Yi-Rong LI

《医学前沿(英文)》 2010年 第4卷 第3期   页码 336-341 doi: 10.1007/s11684-010-0096-4

摘要: The autoimmune regulator (AIRE) is a crucial factor for the induction of central tolerance, and mutations in this gene lead to abnormal immune responses. However, the role of AIRE in autophagy in immune cells, especially in monocytes, is obscure. In the present study, we found that overexpression of AIRE in THP-1 human monocytes resulted in increased endogenous light chain 3 (LC3)-II level and elevated LC3 positive vesicles. Moreover, an autophagy inhibitor or knockdown of AIRE by small interference RNA attenuated these effects. In contrast, the expression of p62/SQSTM1 remained unchanged in THP-1 cells after the corresponding treatment. Our findings indicate that AIRE plays a role in the regulation of autophagy in THP-1 human monocytes.

关键词: autoimmune regulator     autophagy     monocytes     light chain 3 (LC3)    

THE ANTHOCYANIN BIOSYNTHETIC REGULATOR MDMYB1 POSITIVELY REGULATES ASCORBIC ACID BIOSYNTHESIS IN APPLE

《农业科学与工程前沿(英文)》 2021年 第8卷 第2期

摘要:

Ascorbic acid (AsA, vitamin C) is involved in the regulation of many aspects of plant growth and development. It is an essential micronutrient for humans and can prevent scurvy, maintain the health of gums and blood vessels, reduce the level of plasma cholesterol and enhance the immune systen. Apple cultivars Orin and Guanghui were crossed to obtain a group of hybrid offspring with and without red flesh in the course of assessing apple germplasm resources. Unexpectedly, the red-flesh apples had higher AsA contents than other apples. Further studies showed that the anthocyanin biosynthetic regulator MdMYB1 directly activates the expression of dehydroascorbate reductase gene MdDHAR, thus promoting the activity of the DHAR enzyme and the accumulation of AsA. This finding reveals the mechanism leading to high AsA levels in red-flesh apples and suggests a new idea to cultivate red-flesh apples with high AsA contents and produce AsA efficiently and without pollution.

 

THE ANTHOCYANIN BIOSYNTHETIC REGULATOR MDMYB1 POSITIVELY REGULATES ASCORBIC ACID BIOSYNTHESIS IN APPLE

Jianping AN, Xiaofei WANG, Chunxiang YOU, Yujin HAO

《农业科学与工程前沿(英文)》   页码 231-235 doi: 10.15302/J-FASE-2020367

摘要: Ascorbic acid (AsA, vitamin C) is involved in the regulation of many aspects of plant growth and development. It is an essential micronutrient for humans and can prevent scurvy, maintain the health of gums and blood vessels, reduce the level of plasma cholesterol and enhance the immune systen. Apple cultivars Orin and Guanghui were crossed to obtain a group of hybrid offspring with and without red flesh in the course of assessing apple germplasm resources. Unexpectedly, the red-flesh apples had higher AsA contents than other apples. Further studies showed that the anthocyanin biosynthetic regulator MdMYB1 directly activates the expression of dehydroascorbate reductase gene , thus promoting the activity of the DHAR enzyme and the accumulation of AsA. This finding reveals the mechanism leading to high AsA levels in red-flesh apples and suggests a new idea to cultivate red-flesh apples with high AsA contents and produce AsA efficiently and without pollution.

关键词: anthocyanin     apples     ascorbic acid     MdMYB1     vitamin C    

标题 作者 时间 类型 操作

A linear quadratic regulator control of a stand-alone PEM fuel cell power plant

Amar BENAISSA, Boualaga RABHI, Ammar MOUSSI, Dahmani AISSA

期刊论文

Load shedding scheme for the two-area system with linear quadratic regulator

D. TYAGI, Ashwani KUMAR, Saurabh CHANANA

期刊论文

基于随机鲁棒性分析的吸气式高超声速飞行器线性二次调节器设计

Lin CAO, Shuo TANG, Dong ZHANG

期刊论文

铰接车辆的主动转向控制策略研究

Kyong-il KIM,Hsin GUAN,Bo WANG,Rui GUO,Fan LIANG

期刊论文

Linear quadratic optimal controller for cable-driven parallel robots

Saeed ABDOLSHAH,Erfan SHOJAEI BARJUEI

期刊论文

基于线性二次最优化的多智能体编队控制

Chang-bin Yu, Yin-qiu Wang, Jin-liang Shao,brad.yu@anu.edu.au,wh6508@gmail.com,jinliangshao@126.com

期刊论文

New decentralized control technique based on substructure and LQG approaches

Ying LEI, Ying LIN,

期刊论文

Neural network control for earthquake structural vibration reduction using MRD

Khaled ZIZOUNI, Leyla FALI, Younes SADEK, Ismail Khalil BOUSSERHANE

期刊论文

A hybrid LQR-PID control design for seismic control of buildings equipped with ATMD

Amir Hossein HEIDARI, Sadegh ETEDALI, Mohamad Reza JAVAHERI-TAFTI

期刊论文

A new type of quadratic acceleration method

Changqing LI, Menglin LOU,

期刊论文

植物生长调节剂TA乳粉对海带产量和品质的影响

刘德盛,张群

期刊论文

Fibroblast growth factor 21: a novel metabolic regulator from pharmacology to physiology

null

期刊论文

Autoimmune regulator regulates autophagy in THP-1 human monocytes

Liang SHI, Li-Hua HU, Yi-Rong LI

期刊论文

THE ANTHOCYANIN BIOSYNTHETIC REGULATOR MDMYB1 POSITIVELY REGULATES ASCORBIC ACID BIOSYNTHESIS IN APPLE

期刊论文

THE ANTHOCYANIN BIOSYNTHETIC REGULATOR MDMYB1 POSITIVELY REGULATES ASCORBIC ACID BIOSYNTHESIS IN APPLE

Jianping AN, Xiaofei WANG, Chunxiang YOU, Yujin HAO

期刊论文