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Target Controllability of Multi-Layer Networks With High-Dimensional Nodes
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作者 Lifu Wang Zhaofei Li +1 位作者 Ge Guo Zhi Kong 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第9期1999-2010,共12页
This paper studies the target controllability of multilayer complex networked systems,in which the nodes are highdimensional linear time invariant(LTI)dynamical systems,and the network topology is directed and weighte... This paper studies the target controllability of multilayer complex networked systems,in which the nodes are highdimensional linear time invariant(LTI)dynamical systems,and the network topology is directed and weighted.The influence of inter-layer couplings on the target controllability of multi-layer networks is discussed.It is found that even if there exists a layer which is not target controllable,the entire multi-layer network can still be target controllable due to the inter-layer couplings.For the multi-layer networks with general structure,a necessary and sufficient condition for target controllability is given by establishing the relationship between uncontrollable subspace and output matrix.By the derived condition,it can be found that the system may be target controllable even if it is not state controllable.On this basis,two corollaries are derived,which clarify the relationship between target controllability,state controllability and output controllability.For the multi-layer networks where the inter-layer couplings are directed chains and directed stars,sufficient conditions for target controllability of networked systems are given,respectively.These conditions are easier to verify than the classic criterion. 展开更多
关键词 High-dimensional nodes inter-layer couplings multi-layer networks target controllability
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Propofol sedation in routine endoscopy:A case series comparing target controlled infusion vs manually controlled bolus concept
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作者 Riad Sarraj Lorenz Theiler +2 位作者 Nima Vakilzadeh Niklas Krupka Reiner Wiest 《World Journal of Gastrointestinal Endoscopy》 2024年第1期11-17,共7页
BACKGROUND Many studies have addressed safety and effectiveness of non-anaesthesiologist propofol sedation(NAPS)for gastrointestinal(GI)endoscopy Target controlled infusion(TCI)is claimed to provide an optimal sedatio... BACKGROUND Many studies have addressed safety and effectiveness of non-anaesthesiologist propofol sedation(NAPS)for gastrointestinal(GI)endoscopy Target controlled infusion(TCI)is claimed to provide an optimal sedation regimen by avoiding under-or oversedation.AIM To assess safety and performance of propofol TCI sedation in comparison with nurse-administered bolus-sedation.METHODS Fouty-five patients undergoing endoscopy under TCI propofol sedation were prospectively included from November 2016 to May 2017 and compared to 87 patients retrospectively included that underwent endoscopy with NAPS.Patients were matched for age and endoscopic procedure.We recorded time of sedation and endoscopy,dosage of medication and adverse events.RESULTS There was a significant reduction in dose per time of propofol administered in the TCI group,compared to the NAPS group(8.2±2.7 mg/min vs 9.3±3.4 mg/min;P=0.046).The time needed to provide adequate sedation levels was slightly but significantly lower in the control group(5.3±2.7 min vs 7.7±3.3 min;P<0.001),nonetheless the total endoscopy time was similar in both groups.No differences between TCI and bolus-sedation was observed for mean total-dosage of propofol rate as well as adverse events.CONCLUSION This study indicates that sedation using TCI for GI endoscopy reduces the dose of propofol necessary per minute of endoscopy.This may translate into less adverse events.However,further and randomized trials need to confirm this trend. 展开更多
关键词 SEDATION ENDOSCOPY PROPOFOL target controlled infusion Non-anaesthesiologist propofol sedation Adverse event
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Nonlocal multi-target controlled controlled gate using Greenberger–Horne–Zeilinger channel and qutrit catalysis 被引量:1
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作者 陈立冰 路洪 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第7期110-113,共4页
We present a scheme for implementing locally a nonlocal N-target controlled–controlled gate with unit probability of success by harnessing two(N+1)-qubit Greenberger–Horne–Zeilinger(GHZ) states as quantum chan... We present a scheme for implementing locally a nonlocal N-target controlled–controlled gate with unit probability of success by harnessing two(N+1)-qubit Greenberger–Horne–Zeilinger(GHZ) states as quantum channel and N qutrits as catalyser. The quantum network that implements this nonlocal(N+2)-body gate is built entirely of local single-body and two-body gates, and has only(3N+2) two-body gates. This result suggests that both the computational depth of quantum network and the quantum resources required to perform this nonlocal gate might be significantly reduced. This scheme can be generalized straightforwardly to implement a nonlocal N-target and M-control qubits gate. 展开更多
关键词 nonlocal N-target controlled–controlled gate GHZ state qutrit catalysis
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Application of Fuzzy Automata Decision-Making System in Target Control
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作者 Qinggang Wu Zhenyu Han Qing E. Wu 《Journal of Computer and Communications》 2017年第10期16-25,共10页
In order to perform better in target control, this paper proposed a decision-making system method based on fuzzy automata. The decision-making system first preprocessed the signal and then performed a two-level decisi... In order to perform better in target control, this paper proposed a decision-making system method based on fuzzy automata. The decision-making system first preprocessed the signal and then performed a two-level decision on the target to achieve optimal control. The system consisted of four parts: signal preprocessing, contrast decision-making, comprehensive judgment of decision-making and decision-making result. These decision algorithms in target control were given. A concrete application of this decision-making system in target control was described. Being compared with other existing methods, this paper used both global features and local features of target, and used the decision-making system of fuzzy automata for the target control. Simulation results showed that the control effect based on the decision-making system was better than that of the other existing methods. Not only it was faster, but also its correct control rate was higher to be 95.18% for the target control. This research on the control system not only developed the FA theory, but also strengthened its application scope in the field of control engineering. 展开更多
关键词 DECISION-MAKING System COMPREHENSIVE JUDGMENT Fuzzy AUTOMATA target control
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Integrated Guidance and Control of Homing Missiles Against Ground Fixed Targets 被引量:23
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作者 侯明哲 段广仁 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2008年第2期162-168,共7页
This paper presents a scheme of integrated guidance and autopilot design for homing missiles against ground fixed targets. An integrated guidance and control model in the pitch plane is formulated and further changed ... This paper presents a scheme of integrated guidance and autopilot design for homing missiles against ground fixed targets. An integrated guidance and control model in the pitch plane is formulated and further changed into a normal form by nonlinear coordinate transformation. By adopting the sliding mode control approach, an adaptive nonlinear control law of the system is designed so that the missile can hit the target accurately with a desired impact attitude angle. The stability analysis of the closed-loop system is also conducted. The numerical simulation has confirmed the usefulness of the proposed design scheme. 展开更多
关键词 integrated guidance and control pitch plane ground fixed target nonlinear adaptive
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Clinical evaluation of target controlled infusion system for sufentanil administration 被引量:26
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作者 ZHAO Yan ZHANG Li-ping +9 位作者 WU Xin-min JIANG Jian-yu DUAN Jing-li HU Yong-fang LI Min LIU Wei SHENG Xiao-yan NI Cheng XU Mao GUO Xiang-yang 《Chinese Medical Journal》 SCIE CAS CSCD 2009年第20期2503-2508,共6页
Background Sufentanil target controlled infusion (TCI) provides stable analgesia, better hemodynamic control than a bolus injection of intravenous anesthetics, anticipated recovery and improved quality of anesthesia... Background Sufentanil target controlled infusion (TCI) provides stable analgesia, better hemodynamic control than a bolus injection of intravenous anesthetics, anticipated recovery and improved quality of anesthesia during perioperative period. This study evaluated the accuracy and feasibility of TCI system for sufentanil at high concentrations in Chinese surgical patients. Methods Twelve low risk adult patients undergoing elective surgery under general anesthesia were included in this study. Sufentanil was administered with a specific TCI system incorporating the population pharmacokinetic data of sufentanil previously reported, using a target effect-site concentration of sufentanil 4 or 6 ng/ml. Sufentanil TCI duration was 30 minutes. Frequent arterial blood samples were taken during and up to 24 hours after sufentanil TCI for determination of plasma sufentanil concentrations by liquid chromatography-mass spectrometry/mass spectrometry. The changes of circulatory system function during the procedure, recovery profile and adverse effects were recorded. Measured plasma sufentanil concentrations were compared with the values predicted by the TCI system. The bias (median performance error, MDPE), precision (median absolute performance error, MDAPE) and wobble (variability of performance error) of the sufentanil TCI system were determined. Results All patients had stable cardiovascular variables during induction and maintenance of anesthesia. Time to eye opening and extubation were (5.6±1.7) minutes when TCI set to 4 ng/ml and (7.2±2.3) minutes when set to 6 ng/ml. There was no episode of agitation, muscle rigidity or intraoperative awareness. The bias (MDPE), precision (MDAPE) and wobble of the sufentanil TCI system were -3.7%, 18.9% and 19.6% respectively during TCI, and the MDPE, MDAPE and wobble were -29.1%, 31.7% and 15.0% respectively after TCI (up to 8 hours). Conclusions The TCI system programmed for sufentanil at 4 or 6 ng/ml was considered acceptable for clinical use in low risk Chinese surgical patients. But the relatively larger MDPE and MDAPE after TCI suggest improvements of the Dharmacokinetic model are needed. 展开更多
关键词 ANESTHESIA ANALGESIC SUFENTANIL target-controlled infusion tandem mass spectrometry
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Propofol Target-Controlled Infusion Modeling in Rabbits:Pharmacokinetic and Pharmacodynamic Analysis 被引量:2
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作者 陈建颜 易明 +1 位作者 姚尚龙 张雪萍 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2016年第3期428-433,共6页
This study aimed to establish a new propofol target-controlled infusion(TCI) model in animals so as to study the general anesthetic mechanism at multi-levels in vivo. Twenty Japanese white rabbits were enrolled and ... This study aimed to establish a new propofol target-controlled infusion(TCI) model in animals so as to study the general anesthetic mechanism at multi-levels in vivo. Twenty Japanese white rabbits were enrolled and propofol(10 mg/kg) was administrated intravenously. Artery blood samples were collected at various time points after injection, and plasma concentrations of propofol were measured. Pharmacokinetic modeling was performed using Win Nonlin software. Propofol TCI within the acquired parameters integrated was conducted to achieve different anesthetic depths in rabbits, monitored by narcotrend. The pharmacodynamics was analyzed using a sigmoidal inhibitory maximal effect model for narcotrend index(NI) versus effect-site concentration. The results showed the pharmacokinetics of propofol in Japanese white rabbits was best described by a two-compartment model. The target plasma concentrations of propofol required at light anesthetic depth was 9.77±0.23 μg/m L, while 12.52±0.69 μg/m L at deep anesthetic depth. NI was 76.17±4.25 at light anesthetic depth, while 27.41±5.77 at deep anesthetic depth. The effect-site elimination rate constant(ke0) was 0.263/min, and the propofol dose required to achieve a 50% decrease in the NI value from baseline was 11.19 μg/m L(95% CI, 10.25–13.67). Our results established a new propofol TCI animal model and proved the model controlled the anesthetic depth accurately and stably in rabbits. The study provides a powerful method for exploring general anesthetic mechanisms at different anesthetic depths in vivo. 展开更多
关键词 propofol target-controlled infusion modeling rabbit pharmacokinetics pharmacodynamics anesthetic depth
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Multi-rate tracking controller analysis and design for target tracking systems
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作者 洪华杰 黎志强 +2 位作者 范世珣 周擎坤 范大鹏 《Journal of Central South University》 SCIE EI CAS 2013年第11期3049-3056,共8页
As the sampling rates of the inner loop and the outer loop of the target tracking control system are different,a typical digital multi-rate control system was formed.If the traditional single-rate design method was ap... As the sampling rates of the inner loop and the outer loop of the target tracking control system are different,a typical digital multi-rate control system was formed.If the traditional single-rate design method was applied,the low sampling rate loop will seriously impact the dynamical characteristic of the system.After analyzing and calculating the impact law of the low sampling rate loop to the bandwidth and the stability of the tracking system,a kind of multi-rate control system design method was introduced.Corresponding to the different sampling rates of the inner loop and the outer loop,the multi-rate control strategy was constituted by a high sampling rate sub-controller and a low sampling rate sub-controller.The two sub-controllers were designed separately and connected by means of the sampling rate converter.The low sampling rate controller determined the response rapidity of the system,while the high sampling rate controller applied additionally effective control outputs to the system during a sampling interval of the low sampling rate controller.With the introduced high and low sampling rates sub-controllers,the tracking control system can achieve the same performance as a single-rate controller with high sampling rate,yet it works under a much lower sampling rate.The simulation and experimental results show the effectiveness of the introduced multi-rate control design method.It reduces the settling time by 5 times and the over shoot by 4 times compared with the PID control. 展开更多
关键词 multi-rate control system delay target tracking control
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Study of targeted and controlled release of 5-fluorouracil-loaded PLA nanoparticles and microspheres on treatment of gastric tumor
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作者 MAChun-bao LIUXiao-yan +2 位作者 CHANGJin WANGTao ZHANGQing-yu 《中国医学工程》 2005年第2期121-127,共7页
The aim of this paper was to evaluate controlled release behavior and the therapeutic efficacy of 5-FU-loaded Poly(lactic acid) (PLA)microspheres to human gastric cancer xenograft, and the targeting effect of VEGF/5-F... The aim of this paper was to evaluate controlled release behavior and the therapeutic efficacy of 5-FU-loaded Poly(lactic acid) (PLA)microspheres to human gastric cancer xenograft, and the targeting effect of VEGF/5-FU loaded PLA nanoparticles. 5-FU-loaded PLA microspheres were prepared by an emulsion evaporation method, and were characterized by scanning electron microscopy (SEM). 5-FU loaded PLA nanoparticles were characterized by (TEM), and particle size analyzer determined the distribution of nanoparticles size. The release performances of 5-FU microspheres in vitro were studied in PH 7.4 phosphate buffered saline. The therapeutic efficacy of 5-FU-loaded PLA microspheres in vivo were studied using MGC-803 (human stomach cancer) xenograft. 32 nude mice were divided into four groups (n =8), 5-FU loaded PLA microspheres were injected at tumor site. VEGF121 monoclonal antibody was connected with 5-FU loaded PLA nanoparticles through carbodimide. The targeted effect of VEGF 5-FU loaded nanoparticles in vivo were observed by single photon emission computed tomography (SPECT) after tail vein injection at 1 h and 2 h. SEM observation showed that microspheres were spherical, and the diameters of two kinds of microspheres were 1 μm and 5 μm respectively. The mean diameter of nanoparticles was 191.0 nm, and the index of polydispersity was 0.202. The drug was released following biphasic kinetics, initial burst and the following steady phase. 1 μm and 5 μm 5-FU-loaded microspheres both resulted in increased life span (1 μm microspheres median survival time=40.63 days, 5 μm microspheres median survival time=62.25 days), against 5-FU pure drug (median survival time=14.5 days). These results strongly suggest that 5-FU-loaded PLA microspheres increase life span of nude mice bearing MGC-803 tumors. After injection for 2 h, almost all the VEGF/5-FU loaded PLA nanoparticles could centralize at the human gastric cancer xenograft sites. That demonstrated VEGF monoclonal antibody remain its bioactivity after connection with nanoparticles, VEGF/5-FU loaded PLA nanoparticles had very exact targeting function for gastric tumor xenograft. 展开更多
关键词 胃肿瘤 5-氟尿嘧啶 聚乳酸纳米颗粒 微囊体 靶向性 控释性 抗肿瘤药
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Grey Prediction Fuzzy Control of the Target Tracking System in a Robot Weapon 被引量:1
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作者 王建中 姬江涛 王红茹 《Journal of Beijing Institute of Technology》 EI CAS 2007年第4期424-429,共6页
Grey modeling can be used to predict the behavioral development of a system and find out the lead control values of the system. By using fuzzy inference, PID parameters can be adjusted on line by the fuzzy controller ... Grey modeling can be used to predict the behavioral development of a system and find out the lead control values of the system. By using fuzzy inference, PID parameters can be adjusted on line by the fuzzy controller with PID parameters self-tuning. According to the characteristics of target tracking system in a robot weapon, grey prediction theory and fuzzy PID control ideas are combined. A grey prediction mathematical model is constructed and a fuzzy PID controller with grey prediction was developed. Simulation result shows fuzzy PID control algorithm with grey prediction is an efficient method that can improve the control equality and robustness of traditional PID control and fuzzy PID control, and has much better performance for target tracking. 展开更多
关键词 target tracking grey prediction modeling fuzzy PID control
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煤矸石自燃的关键影响因素及治理方法研究现状 被引量:2
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作者 王启宝 敖立新 +3 位作者 张凯 杨康 唐玉伟 谭栩荧 《洁净煤技术》 CAS CSCD 北大核心 2024年第1期228-238,共11页
煤矸石作为煤炭的伴生产物,长期堆存过程中自燃现象频发,直接或间接产生生态污染、水体污染、地质灾害等诸多问题,造成巨大经济损失和人员伤亡。煤矸石从堆积初期到燃烧状态受诸多因素影响,包括自身性质、自燃条件和外部环境等,是一个... 煤矸石作为煤炭的伴生产物,长期堆存过程中自燃现象频发,直接或间接产生生态污染、水体污染、地质灾害等诸多问题,造成巨大经济损失和人员伤亡。煤矸石从堆积初期到燃烧状态受诸多因素影响,包括自身性质、自燃条件和外部环境等,是一个复杂的物理化学反应过程。为提高煤矿矿区矸石自燃的防治能力,分析了煤矸石自燃理论的研究现状,系统总结了现阶段国内外学者对煤矸石自燃机理和治理方法的研究进展。围绕可燃物、氧气、温度3个影响煤矸石自燃的必要因素,提出了引发自燃的主要关键影响因素和作用过程机理。较全面介绍已有煤矸石山自燃防治的主要方法,对比分析了各种常规煤矸石自燃灭火手段以及治理技术的优缺点,指出了常规简单技术治理效果的局限性。针对煤矸石作为砂、石等替代材料,回填露天矿坑、采煤塌陷区等区域进行土地整治和生态修复,提出在防治过程中要明确自燃治理的控制对象,提升防灭火材料的特定性能,通过智能化设备提高辨识准确性进行精细化监控,并运用多种监测预警技术协同自燃防治材料多手段多方法运用综合治理,并提出了煤矸石自燃防治技术的未来发展和矿用防灭火材料的研究方向,为后续开展煤矸石自燃机理研究及自燃防治工程应用提供参考和理论支持。 展开更多
关键词 煤矸石 自燃过程 控制对象 治理方法
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Target-controlled Infusion of Propofol and Remifentanil for a patient with Ablation of Atrial Fibrillation
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作者 Su-min Gao Zheng-chao Yang Ting-ting Wang Shang-long Yao 《麻醉与监护论坛》 2014年第1期69-72,共4页
关键词 芬太尼 异丙酚 患者 颤动 心房 麻醉技术 评估标准 安全性
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老年髋关节置换术中实施丙泊酚闭环靶控输注麻醉的效果及对患者术后谵妄风险的影响 被引量:1
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作者 王亚群 邱新建 +3 位作者 彭杰成 王辉 汪东学 王玲 《临床和实验医学杂志》 2024年第10期1118-1120,F0003,共4页
目的研究老年髋关节置换术中实施丙泊酚闭环靶控输注麻醉的效果及对术后谵妄风险的影响。方法回顾性选取2020年1月至2023年1月入安庆市第一人民医院接受治疗的90例髋关节骨折老年患者,择期行髋关节置换术。参考麻醉方式不同分为A组、B组... 目的研究老年髋关节置换术中实施丙泊酚闭环靶控输注麻醉的效果及对术后谵妄风险的影响。方法回顾性选取2020年1月至2023年1月入安庆市第一人民医院接受治疗的90例髋关节骨折老年患者,择期行髋关节置换术。参考麻醉方式不同分为A组、B组和C组,每组各30例。A组给予丙泊酚闭环靶控持续输注麻醉,B组给予丙泊酚开环靶控持续输注麻醉,C组给予丙泊酚人工持续输注麻醉。比较3组患者的术中相关指标(麻醉时间、手术时间以及拔管时间)、麻醉相关指标(术中丙泊酚总计用量、术中维持泵调节次数)、血流动力学变化[麻醉诱导开始(T_(0))、插管(T_(1))、手术开始(T_(2))、手术结束(T_(3))、拔管(T_(4))的平均动脉压、心率以及脑电双频指数(BIS)值]情况、术后恢复情况及术后谵妄发生情况。结果(1)术中指标:3组患者麻醉时间、手术时间以及拔管时间比较,差异均无统计学意义(P>0.05)。(2)麻醉相关指标:A组患者术中丙泊酚总计用量、术中维持泵调节次数均明显低于B、C组,差异均有统计学意义(P<0.05);B组患者单位麻醉时间内丙泊酚用量、单位手术时间内丙泊酚用量均明显高于A、C组,差异均有统计学意义(P<0.05)。(3)血流动力学:A组T_(2)、T_(3)时平均动脉压均高于B组、C组,A组T_(4)时的平均动脉压更加接近于T_(0);3组患者不同时刻心率差异无统计学意义(P>0.05);A组T_(2)、T_(3)时BIS值均低于B组、C组,差异均有统计学意义(P<0.05)。(4)术后恢复情况:A组患者PACU停滞时间、自主呼吸恢复时间、指令反应恢复时间均明显低于B、C组,差异均有统计学意义(P<0.05)。(5)术后谵妄:A组患者术后谵妄发生率为16.67%,显著低于B、C组(40.00%、46.67%),差异均有统计学意义(P<0.05)。结论老年髋关节置换术中采用丙泊酚靶控输注麻醉可减少丙泊酚用量,术中生命体征更加平稳,可降低人工操作次数,术后麻醉苏醒更快,且术后谵妄发生率也更低,是老年患者首选的麻醉方案。 展开更多
关键词 髋关节置换术 老年人 闭环靶控输注 丙泊酚 谵妄
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The law of anti-VCAM-1 targeted microbubbles adhesion to activated endothelial cells under controlled shear flow
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作者 Lie Zhang,Hong Yang,Yiyao Liu(Department of Biophysics,School of Life Science and Technology,University of Electronic Science and Technology of China,Chengdu 610054,Sichuan,China) 《医用生物力学》 EI CAS CSCD 2009年第S1期11-11,共1页
Microbubbles can enhance the detection in noninvasive ultrasound imaging.Recently,targeted microbubbles have been developed to selectively adhere to specific and overexpressed p molecules in endothelial cells in some ... Microbubbles can enhance the detection in noninvasive ultrasound imaging.Recently,targeted microbubbles have been developed to selectively adhere to specific and overexpressed p molecules in endothelial cells in some pathologic conditions.However,the law of 展开更多
关键词 HUVECs The law of anti-VCAM-1 targeted microbubbles adhesion to activated endothelial cells under controlled shear flow
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Robust attitude control for rapid multi-target tracking in spacecraft formation flying
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作者 袁长清 李俊峰 +1 位作者 王天舒 宝音贺西 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第2期185-198,共14页
A robust attitude tracking control scheme for spacecraft formation flying is presented. The leader spacecraft with a rapid mobile antenna and a camera is modeled. While the camera is tracking the ground target, the an... A robust attitude tracking control scheme for spacecraft formation flying is presented. The leader spacecraft with a rapid mobile antenna and a camera is modeled. While the camera is tracking the ground target, the antenna is tracking the follower spacecraft. By an angular velocity constraint and an angular constraint, two methods are proposed to compute the reference attitude profiles of the camera and antenna, respectively. To simplify the control design problem, this paper first derives the desired inverse system (DIS), which can convert the attitude tracking problem of 3D space into the regulator problem. Based on DIS and sliding mode control (SMC), a robust attitude tracking controller is developed in the presence of mass parameter uncertainties and external disturbance. By Lyapunov stability theory, the closed loop system stability can be achieved. The numerical simulations show that the proposed robust control scheme exhibits significant advantages for the multi-target attitude tracking of a two-spacecraft formation. 展开更多
关键词 attitude control formation flying multi-body spacecraft robust control multi-target tracking
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基于嵌入式技术的运动目标控制与自动追踪系统设计 被引量:1
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作者 梁瑞 《集成电路与嵌入式系统》 2024年第1期89-93,共5页
针对目前移动机器人运动目标定位不准确和追踪过程中容易丢失的问题,设计了一种基于嵌入式技术的运动目标控制与自动追踪系统。本系统以光斑模拟运动目标,通过算法编程不但可以实现目标的运动轨迹控制,还可对其运动轨迹进行自动追踪。... 针对目前移动机器人运动目标定位不准确和追踪过程中容易丢失的问题,设计了一种基于嵌入式技术的运动目标控制与自动追踪系统。本系统以光斑模拟运动目标,通过算法编程不但可以实现目标的运动轨迹控制,还可对其运动轨迹进行自动追踪。本设计以嵌入式芯片STM32F103为核心,通过OpenMV进行图像数据处理,并由PID精确算法调节舵机,从而控制光斑在屏幕上按照设定程序进行移动和追踪。经测试,该系统能够准确地完成运动目标的控制和自动追踪任务,反应灵敏,性价比高,可广泛应用于运动目标追踪等智能控制设备中。 展开更多
关键词 嵌入式技术 运动目标控制 STM32F103 PID OpenMV
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Unified Modeling Approach of Kinematics, Dynamics and Control of a Free-Flying Space Robot Interacting with a Target Satellite 被引量:3
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作者 Murad Shibli 《Intelligent Control and Automation》 2011年第1期8-23,共16页
In this paper a unified control-oriented modeling approach is proposed to deal with the kinematics, linear and angular momentum, contact constraints and dynamics of a free-flying space robot interacting with a target ... In this paper a unified control-oriented modeling approach is proposed to deal with the kinematics, linear and angular momentum, contact constraints and dynamics of a free-flying space robot interacting with a target satellite. This developed approach combines the dynamics of both systems in one structure along with holonomic and nonholonomic constraints in a single framework. Furthermore, this modeling allows consid-ering the generalized contact forces between the space robot end-effecter and the target satellite as internal forces rather than external forces. As a result of this approach, linear and angular momentum will form holonomic and nonholonomic constraints, respectively. Meanwhile, restricting the motion of the space robot end-effector on the surface of the target satellite will impose geometric constraints. The proposed momentum of the combined system under consideration is a generalization of the momentum model of a free-flying space robot. Based on this unified model, three reduced models are developed. The first reduced dynamics can be considered as a generalization of a free-flying robot without contact with a target satellite. In this re-duced model it is found that the Jacobian and inertia matrices can be considered as an extension of those of a free-flying space robot. Since control of the base attitude rather than its translation is preferred in certain cases, a second reduced model is obtained by eliminating the base linear motion dynamics. For the purpose of the controller development, a third reduced-order dynamical model is then obtained by finding a common solution of all constraints using the concept of orthogonal projection matrices. The objective of this approach is to design a controller to track motion trajectory while regulating the force interaction between the space robot and the target satellite. Many space missions can benefit from such a modeling system, for example, autonomous docking of satellites, rescuing satellites, and satellite servicing, where it is vital to limit the con-tact force during the robotic operation. Moreover, Inverse dynamics and adaptive inverse dynamics control-lers are designed to achieve the control objectives. Both controllers are found to be effective to meet the specifications and to overcome the un-actuation of the target satellite. Finally, simulation is demonstrated by to verify the analytical results. 展开更多
关键词 Free-Flying Space ROBOT target Satellite SERVICING FLYING ROBOT Adaptive control Inverse Dynamic control HUBBLE Telescope
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一种靶弹多功能控制器设计与实现 被引量:1
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作者 杜江 王鑫 +1 位作者 王刚 付京来 《计算机测量与控制》 2024年第3期176-180,203,共6页
靶弹是模拟敌方来袭导弹技战术特性的实体空中靶标;针对退役导弹改装靶弹中面临的改装线路复杂、对动目标供靶精度不足等实际问题,对靶弹飞行控制规律和改装设计方法进行了研究探索,创新了靶弹制导控制方法,综合采用靶弹飞行控制回路状... 靶弹是模拟敌方来袭导弹技战术特性的实体空中靶标;针对退役导弹改装靶弹中面临的改装线路复杂、对动目标供靶精度不足等实际问题,对靶弹飞行控制规律和改装设计方法进行了研究探索,创新了靶弹制导控制方法,综合采用靶弹飞行控制回路状态转换、动目标供靶航路精确控制、靶弹功能扩展等关键技术,设计研制了集电气改装、接口转换、目标导引、安全控制等功能于一体的靶弹多功能控制器,实现了退役飞航导弹到多用途靶弹的通用化、标准化改装,探索了一种经济而有效的靶弹开发方法;试验结果表明,该多功能控制器具备简便可靠、工作量小、通用性好、弹道控制灵活等突出特点,较好地解决了靶弹改装难题,满足了防空武器系统试验训练的需要。 展开更多
关键词 靶弹 改装 动目标供靶 多功能控制器
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体外冲击波响应型唑来膦酸钙纳米颗粒靶向控释对骨质疏松骨代谢及骨量的影响
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作者 李浩 肖健 +3 位作者 胡帆 王策 陈奎 邢更彦 《中国医学前沿杂志(电子版)》 CSCD 北大核心 2024年第7期47-54,I0002,共9页
目的研究体外冲击波(extracorporeal shock wave,ESW)响应型唑来膦酸(zoledronic acid,ZOL)钙纳米颗粒(ZOL-Ca nanoparticals,ZCNP)的制备及其靶向控释对骨质疏松骨代谢及骨量的影响。方法通过模板法以ZOL为磷源,CaCl2为钙源制备ZCNP。... 目的研究体外冲击波(extracorporeal shock wave,ESW)响应型唑来膦酸(zoledronic acid,ZOL)钙纳米颗粒(ZOL-Ca nanoparticals,ZCNP)的制备及其靶向控释对骨质疏松骨代谢及骨量的影响。方法通过模板法以ZOL为磷源,CaCl2为钙源制备ZCNP。利用扫描电子显微镜、动态光散射对ZCNP进行表征。通过紫外可见吸收光谱及电感耦合等离子体光发射光谱法评估ZOL的负载以及载药率。利用CCK-8法检测ZCNP对鼠源骨髓单核细胞(bone marrow mononu-clear cells,BMMs)活力的影响;采用溶血实验检测ZCNP的生物相容性。通过荧光标记ZCNP对其骨靶向性进行验证。采用药物释放实验验证了ZCNP的ESW响应性。在体外,利用TRAP染色检验ZCNP的破骨抑制情况;ARS染色检验ZCNP对成骨活性的影响。在体内,利用卵巢摘除骨质疏松模型验证ZCNP对骨量的影响。结果ZCNP呈类球形结构,约60 nm。ZCNP的ZOL负载率为(59.68±1.48)%。ZCNP在0、0.01、0.1、1、10μmol/L浓度下对小鼠BMMs的细胞活性影响无明显差异(P>0.05)。ZCNP在ESW作用下可快速释放ZOL。ESW+ZCNP可抑制破骨细胞活性,促进成骨细胞增殖。ESW+ZCNP可明显提高卵巢摘除骨质疏松模型局部骨量。结论ESW响应型ZCNP可通过有效精准靶向控释,抑制破骨,促进成骨提升卵巢摘除模型局部骨量,预防骨质疏松性骨折。 展开更多
关键词 体外冲击波 唑来膦酸 靶向控释 骨质疏松性骨折
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基于改进反步滑模控制算法的拖轮自主靠泊控制 被引量:1
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作者 刘佳仑 董智霖 +2 位作者 李诗杰 游旭 胡英俊 《中国舰船研究》 CSCD 北大核心 2024年第1期119-127,共9页
[目的]针对拖轮的自主靠泊控制问题,研究基于虚拟船领导的目标跟踪控制策略在拖轮自主靠泊中的应用。[方法]首先,将拖轮的自主靠泊过程转变为虚拟拖轮和实际拖轮的目标跟踪控制过程;然后,设计靠泊系统的运动学模型,考虑靠泊场景中的特... [目的]针对拖轮的自主靠泊控制问题,研究基于虚拟船领导的目标跟踪控制策略在拖轮自主靠泊中的应用。[方法]首先,将拖轮的自主靠泊过程转变为虚拟拖轮和实际拖轮的目标跟踪控制过程;然后,设计靠泊系统的运动学模型,考虑靠泊场景中的特殊环境干扰,使用反步法和滑模控制法(SMC)设计全回转尾推进拖轮的自主靠泊控制器,提供了3种不同的滑模面设计并使用李雅普诺夫函数进行稳定性验证;最后,采用仿真实验的方式,通过靠泊轨迹、速度误差和距离误差来对控制的效果进行验证。[结果]仿真实验结果表明,设计的拖轮自主靠泊控制策略以及控制器在拖轮自主靠泊场景中具有较好的效果,面对系统的不确定干扰有较好的表现。[结论]该控制策略以及靠泊控制器的适用性以及鲁棒性较好,以全新的角度实现了拖轮自主靠泊控制,为后续拖轮的靠泊控制研究提供了新的方向。 展开更多
关键词 欠驱动拖轮 自主靠泊 目标跟踪控制 反步法 滑模控制
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