30 resultados para Control systems

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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Processing networks are a variant of the standard linear programming network model which are especially useful for optimizing industrial energy/environment systems. Modelling advantages include an intuitive diagrammatic representation and the ability to incorporate all forms of energy and pollutants in a single integrated linear network model. Added advantages include increased speed of solution and algorithms supporting formulation. The paper explores their use in modelling the energy and pollution control systems in large industrial plants. The pollution control options in an ethylene production plant are analyzed as an example. PROFLOW, a computer tool for the formulation, analysis, and solution of processing network models, is introduced.

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The properties of positively invariant sets are involved in many different problems in control theory, such as constrained control, robustness analysis, synthesis and optimization. In this paper we provide an overview of the literature concerning positively invariant sets and their application to the analysis and synthesis of control systems.

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This paper considers the chaos synchronization of the modified Chua's circuit with x vertical bar x vertical bar function. We firstly show that a couple of the modified Chua systems with different parameters and initial conditions can be synchronized using active control when the values of parameters both in drive system and response system are known aforehand. Furthermore, based on Lyapunov stability theory we propose an adaptive active control approach to make the states of two identical Chua systems with unknown constant parameters asymptotically synchronized. Moreover the designed controller is independent of those unknown parameters. Numerical simulations are given to validate the proposed synchronization approach.

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为解决网络延时对网络化控制系统性能的影响,从控制的角度提出基于系统模型的补偿器设计方案以解决网络延时问题.通过对广义预测控制算法GPC状态空间形式的推导,设计具有多步预测功能的网络控制器,实现前向通道的延时补偿;构造具有延时补偿功能的状态观测器以补偿反馈通道延时.分析了使用上述延时补偿策略所构成的闭环网络控制系统的稳定性.通过对不同网络延时补偿的仿真实验,证实了该补偿算法能有效改善控制系统性能并保持系统的稳定.

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The wind error of the double-edge technique Doppler lidar due to the instability of injection-seeding solid laser and the drift of interferometer s spectrum was analyzed. Corresponding numerical simulation indicated that if the wind error of 1 m/s was achieved, the unsuccessful injection-seeding pulses should be less than 0.06% in integration time of 5 min. (30000 pulses). In the respect of spectrum drift of the interferometer, double temperature control systems were used and the accuracy of minus or plus 0.002°C was obtained, corresponding to the wind error of minus or plus 0.226 m/s. Monitoring of buildup time of the injection-seeding laser and temperature of the interferometer was significantly to improve the invertion accuracy of wind error by rejecting the data with frequency jumping and drifting. Researches of injection-seeding and spectrum stability of the interferometer were practical for the development of double-edge wind lidar.}

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We investigate theoretically the interplay between Zeeman splitting, Rashba spin-orbit interaction (RSOI), and Dresselhaus spin-orbit interaction (DSOI) and its influence on the magnetotransport property of two-dimensional electron gas (2DEG) at low temperature. Our theoretical results show that the nodes of the beating patterns of the magnetoresistivity rho(xx) for 2DEG with RSOI or DSOI alone depend sensitively on the total spin splitting induced by these three spin splitting mechanisms. It is interesting to find that the eigenstates in the presence of RSOI alone are connected with those in the presence of DSOI alone but with opposite Zeeman splitting by a time-reversal transformation. Consequently, the magnetoresistivities exhibit exactly the same oscillation patterns for these two cases. For strong RSOI or DSOI alone, the magneto-oscillation of rho(xx) shows two distinct periods. For 2DEG with both RSOI and DSOI, the beating patterns vanish for equal RSOI and DSOI strengths and vanishing Zeeman splitting. They will appear again, however, when Zeeman splitting or the difference between RSOI and DSOI strengths increases.

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在工控领域中,企业实时数据的管理和共享是企业在提高自动化程度过程中面临的重要课题。该文在着重分析了工控领域中实时数据库的应用需求之后,详细介绍了实时数据库系统Agilor开放式的系统结构及其数据处理中所采用的关键技术。

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A single longitudinal mode and narrow line width external cavity semiconductor laser is proposed. It is constructed with a semiconductor laser, collimator, a flame grating, and current and temperature control systems. The one facet of semiconductor laser is covered by high transmission film, and another is covered by high reflection film. The flame grating is used as light feedback element to select the mode of the semiconductor laser. The temperature of the constructed external cavity semiconductor laser is stabilized in order of 10(-3)degreesC by temperature control system. The experiments have been carried out and the results obtained-the spectral fine width of this laser is compressed to be less than 1.4MHz from its original line-width of more than 1200GHz and the output stability (including power and mode) is remarkably enhanced.

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何首乌为常用中药,由何首乌及含何首乌的中成药制剂所引起的不良反应也时见报道,科学阐明不良反应的物质基础并提出解决方案对何首乌的使用十分重要。本论文研究了何首乌炮制前后KM小鼠肝脏毒性基因表达谱、生物活性及化学成分的变化。所获结果支持何首乌炮制的目的是减毒、改性(改变药效),何首乌生、熟异治的观点。制首乌对抑郁症的效果显著优于生首乌,这与本草所记载的何首乌炮制后补肝肾、益精血,归肝、肾经一致。 主要结果如下: 1、 生、制首乌的毒理基因芯片研究结果 何首乌的不良反应主要表现在肝损害方面。本研究建立了生何首乌和制何首乌不同剂量的肝毒性作用模型,体重指标统计发现生何首乌各剂量组平均体重显著下降,中剂量组(10 g/kg.d)体重下降20 %,高剂量组(20 g/kg.d)体重下降42%,50%动物死亡,提示动物机体能量代谢障碍;基因芯片研究结果表明何首乌是CYP450的抑制剂,生何首乌相对于制何首乌CYP3A4、CYP4A5显著下调,导致毒性成分在体内的吸收增加,服用大剂量的生何首乌后产生明显的肝毒性;主要对以下六条Pathway产生影响:①PPAR signaling pathway,主要毒性靶基因有RXRB CYP7a1、Acadl、Apoa2、Cyp4a、 FABP2 、MAPKKK5等基因。②Calcium signaling pathway,主要毒性靶基因有CAMK2B、CACNA1F、S100A1、 F2R、Ryr1、Slc8a2、Camk4 ③Neuroactive ligand-receptor interaction,主要毒性靶基因有Chrm4、 Ntsr2 、 GABRR1、 GRIK3、F2R等基因。④Wnt signaling pathway,主要毒性靶基因有Daam2、Rac1 等基因。⑤Complement and coagulation cascades,主要毒性靶基因有F2R、Serpina1b、Cfi 、FGA等基因。⑥Oxidative hosphorylation,主要毒性靶基因有Atp5e、NDUFA1等基因。生何首乌毒性明显强于制首乌,且生何首乌水煎液的毒性大于生何乌首丙酮提取物的毒性,这一结果表明,何首乌主要的毒性成分很可能并不仅仅是传统所认为的以大黄素为代表的蒽醌类化合物,而是何首乌中大量存在的有效组分二苯乙烯苷与大黄素相互作用的结果,这一研究结果与前述的何首乌对肝药酶的影响是一致的。后续生、制首乌的化学成分差异研究表明,炮制后二苯乙烯苷含量明显降低:生首乌为5.512 %、清蒸制首乌为3.811 %、豆制首乌为3.538 %,大黄素的含量炮制后显著升高,生首乌为0.094 %、清蒸制首乌为0.119 %、豆制首乌为0.126 %。 2 生、制首乌药效差异研究结果 本文采用慢性中等强度不可预知应激刺激模型(chronic unpredictable mild stress, CUMS)和动物行为绝望实验法,研究生、制首乌抗抑郁活性的差异,制首乌(5 g/kg.d)与模型组相比有显著差异(P< 0.01),生首乌制首乌(5g/kg.d)与模型组相比无显著差异,这一结果表明制首乌抗抑郁活性显著优于生首乌。 本文比较了生、制首乌对四氧嘧啶糖尿病模型小鼠血糖的影响的差异,生首乌(5 g/kg.d)与模型组相比有显著差异(P< 0.01),制首乌(5 g/kg.d)与模型组相比无显著差异,这一结果表明生首乌降糖活性优于制首乌。这一结果与历代中医古书中生首乌治疗消渴症(糖尿病)的记载一致。 3生、制首乌化学成分差异的研究结果 本文选用HPLC-DAD指纹图谱技术结合药效成分含量测定来研究生、制首乌化学成分的差异。炮制后,何首乌中的主要化学成分并未消失,只是其含量发生了改变。炮制后二苯乙烯苷含量明显降低:生首乌为5.512 %、清蒸制首乌为3.811 %、豆制首乌为3.538 %,大黄素的含量炮制后显著升高,生首乌为0.094 %、清蒸制首乌为0.119 %、豆制首乌为0.126 %。 综上所述,炮制前后何首乌中二苯乙烯苷和大黄素含量比的变化可能是何首乌炮制减毒、改性的物质基础。 根据上述结果我们建立了生、制首乌的质量控制新模式。 In recent years, some adverse drug reactions (ADR) about some traditional Chinese medicine were reported at times. As a Chinese medicine most in use, the ADRs of Radix Polygoni multiflori (RPM) and the medicines containing the RPM were also mentioned. The resolution of the problems caused by the ADRs is very important for the use of the RPM as a medicine. The process (or preparation) is a significant feature for the clinical use of the Chinese medicine and an important technology for the safe use and good effect of the Chinese medicine. By processing, the toxicity of the Chinese medicine can be reduced, its properties can be changed and curative effect can be enhanced at the same time. The changes of the gene expression profiles for KM mice hepatotoxic effects, and the change of the biological activity and the chemical composition after being processed of the RPm were studied in the present dissertation. The RPm heatotoxicity mechanism and the toxicity target genes were explained on the gene level for the first time. With the antidepressant activity, and the hypoglycemic effect as the target, the differences on the pharmacodynamics between the processed RPm and unprocessed RPm, for the first time, were investigated. The results obtained show that the antidepressant activity of the processed RPM is far higher than the ones of unprocessed RPm. As we know, the results were reported for the first time. The quality control systems (QCS) for the processed and the unprocessed RPm were founded. The HPLC-DAD was used in the systems founded on the basis of the toxicology and the pharmacodynamics experiments. As we know, the OCSs were reported for the first time. The above-mentioned experimental results confirm that the unique process theory of the traditional Chinese medicine (TCM) used for the process of the Radix Polygoni multiflori (RPm) is correct, i.e after being processed the toxicity of the RPm decreases and its Pharmacodynamic effects change. It is known to author that there have been no similar reports in the literatures up to now. The main experimental results are summarized as follows: 1 The results on the mice toxicology gene chip for the unprocessed and processed RPm The KM mice hepatotoxic model caused by the RPm at the different dosages was established in the present study. The results obtained show that the mouse average body weight obviously decreased in the groups at the different dosages of the unprocessed RPm: the 10 g/kg.d .group decreased 20%; 20 g/kg.d. group decreased 42%, and 50% mice died at 20 g/kg.d. group. The main experimental results on the mice toxicology gene chip The RPm is the CYP450 inhibitor. As compared with the processd RPm, the CYP3A4, CYP4A5 of the unprocessed RPm demonstrate the marked downregulation, which leads to the increase of the poison absorbtion into the body with the result that the unprocessed RPm yields the marked hepatotoxication. The hepatotoxication was produced because the following 6 pathways were affected: ①PPAR signaling pathway, the chief toxicity target genes are RXRB, CYP7a1, Acadl, Apoa2, Cyp4a, FABP2 and MAPKKK5 etc. ②Calcium signaling pathway, the chief toxicity target genes are CAMK2B, CACNA1F, S100A1, F2R, Ryr1,Slc8a2 and Camk4 etc. ③Neuroactive ligand-receptor interaction, the chief toxicity target genes are Chrm4, Ntsr2, GABRR1, GRIK3 and F2R etc. ④Wnt signaling pathway, the chief toxicity target genes are Daam2, Rac1 etc. ⑤Complement and coagulation cascades, the chief toxicity target genes are F2R, Serpina1b, Cfi and FGA etc. ⑥Oxidative phosphorylation, the chief toxicity target genes are Atp5e, NDUFA1 etc. The above experimental results, for the first time , demonstrate on the gene level that the unprocessed Rpm toxicity is far stronger than the processed RPm one, and the toxicity of the water decoction of the unprocessed RPm is greater than the one of its acetone extracts, which shows that the chief toxicity components of the RPm are probably not only the anthraquinones, for example, the emodin, but the complex compounds produced by the interaction between the emondin and the stilbene glucoside which is the largest component of the unprocessed RPm. The result is accordance with the above effect of the RPm on the hepatic drugenzyme. Aftter being processed, in fact, the content of the stibene glucoside in the RPm markedly decreases. 2. The results on the pharmacodynamic differences between the unprocessed and processed RPm The results obtained show that the effects of processing on RPm pharmacodynamic behaviour received in the Chinese Material Medica are correct. It is known to author that this is the first experimental result in the research materials now available. The chief results are as follows: For the treatment of the antidepressant, the curative effect of the processed RPm is far better than the one of the unprocessed RPm. By contrast with the above results, the hypoblycemic effect of the unprocessed RPm is better than the one of the processed RPm. 3. The results on the Chemical Composition The results obtained by using HPLC-DAD fingerprint and by the determination of effective component content show that the main chemical components in the RPm after being processed do not disappear, but their contents change. The contents of the stilbene glucoside (SG) and emodin in the different samples were determined as follows: SG contents 5.512 % for the unprocessed RPm 3.811 % for the processed RPm (Steamed) 3.588 % for the processed RPm (black soybean) Emodin contents 0.094 % for the unprocessed RPm 0.119 % for the processed RPm (Steamed) 0.126 % for the processed RPm (black soybean) The combination of above experimental results on the toxicity, the pharmacodynamics and the chemical composition indicates that the changes of the content ratio of SG/emodin may be the substance base of the toxicity decrease and pharmacodynamic changes of the RPM by the processing.

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FPGA and dedicated micro-controller chips are widely used in HIRFL-CSR monitor and control systems.This paper discusses the characteristics of HIRFL-CSR s dedicated micro-controllers and it s requirement for micro-controllers. Using programmable technology and Nios-Ⅱ processor,we have designed and implemented a reconfigurable embedded micro(controller in altera cycloneⅡ2c35f484 FPGA. The micro-controller which has low hardware cost and 185 MHz maximum operating frequency can replace the dedicated micro-cont...中文文摘:讨论并参考了冷却储存环目前使用的专用微控制器的特点和其对微控制器的需求,采用可编程技术和Nios-Ⅱ处理器,在altera-cycloneII2c35f484芯片内实现可重构微控制器。该微控制器硬件资源消耗少,最大工作频率可达185MHz,可代替目前在监控系统中大量使用的专用微控制器芯片,减小硬件设计复杂度、节约成本。

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提出一个在线双向适应的笔手势界面框架,该框架针对传统笔手势界面中静态手势识别器不能支持用户的个性化输入以及用户在笔手势界面中面临的手势记忆问题,提出了在线双向适应的策略:一方面系统能够适应用户(系统可以在线支持用户的个性化输入);另一方面用户可以学习系统(用户可以学习系统提供的某些笔手势).该框架包括5个部分:(1)双向适应笔手势输入解释模型;(2)双向适应笔手势输入解释流程;(3)上下文优先级定义;(4)纠错和模糊消解界面;(5)在线笔手势查询帮助系统.在该框架的指导下作者开发了一个原型系统并进行了对比实验评估.结果表明该框架在可用性上具有较大的优势.

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视觉伺服可以应用于机器人初始定位自动导引、自动避障、轨线跟踪和运动目标跟踪等控制系统中。传统的视觉伺服系统在运行时包括工作空间定位和动力学逆运算两个过程,需要实时计算视觉雅可比矩阵和机器人逆雅可比矩阵,计算量大,系统结构复杂。本文分析了基于图像的机器人视觉伺服的基本原理,使用BP神经网络来确定达到指定位姿所需要的关节角度,将视觉信息直接融入伺服过程,在保证伺服精度的情况下大大简化了控制算法。文中针对Puma560工业机器人的模型进行了仿真实验,结果验证了该方法的有效性。

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提出了一种动态规则设定和检验的实现方法。该方法可在不改变智能测控系统主体程序的情况下,灵活地改变其工作方式;不仅占用系统资源极少,而且提高了系统的运行效率;有效地解决了测控系统中难以实现动态规则的设定和检验问题。给出了其具体实现,该方法有广泛的适用性。