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5594. CONTROL 2018 a trendy vývoje metrologie

Creator:
Kůr, Jan
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
CONTROL, metrology, trends, automatic machines, laboratory gauges, metrologie, trendy, automaty, and laboratorní měřidla
Language:
Czech
Description:
The world's largest trade fair CONTROL 2018 for measurement and control technology was traditionally held on 22 - 27 April 2018 in Stuttgart, a city closely linked to the German automotive industry. The fair of steady rising extent and quality level was attended by more than 900 exhibitors from 32 countries. and Největší světový veletrh měřicí techniky a řízení jakosti CONTROL se koná tradičně ve Stuttgartu - městě úzce spjatém s německým automobilovým průmyslem. Letos se uskutečnil ve dnech 23.-27. 4. 2018 jeho 32. ročník. Zúčastnilo se ho přes 900 vystavovatelů z 32 zemí. Rozsah i úroveň veletrhu mají trvale vzestupnou tendenci.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

5595. Control a state dependent dynamic graph to a pre-specified structure

Creator:
Chen, Fei, Chen, Zengqiang, Liu, Zhongxin, and Yuan, Zhuzhi
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
state-dependent graph, Lasalles´s invariant principle, and dynamic system
Language:
English
Description:
Recent years have witnessed an increasing interest in coordinated control of distributed dynamic systems. In order to steer a distributed dynamic system to a desired state, it often becomes necessary to have a prior control over the graph which represents the coupling among interacting agents. In this paper, a simple but compelling model of distributed dynamical systems operating over a dynamic graph is considered. The structure of the graph is assumed to be relied on the underling system's states. Then by following a proper protocol, the state-dependent dynamic graph is driven to a pre-specified structure. The main results are derived via Lasalle's Invariant Principle and numerical examples that find very good agreements with the analytical results are also included.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

5596. Control mechanisms of photosynthetic capacity under elevated CO2 concentration: evidence from three experiments with Norway spruce trees

Creator:
Urban, O., Pokorný, R., Kalina, J., and Marek, M. V.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
down-regulation, nitrogen, Picea abies, sing strength, and sun and shade needles
Language:
Multiple languages
Description:
Twelve-year-old Norway spruce (Picea abies [L.] Karst.) were exposed to ambient (AC) or elevated (EC) [ambient + 350 μmol(CO2) mol-1] CO2 concentration [CO2] using the facilities of open-top-chambers (OTCs) and glass domes (GDs). A combination of gas exchange measurements and application of a biochemical model of photosynthesis were used for the evaluation of CO2 assimilation characteristics. Morphological change was assessed on the base of specific leaf area (SLA). Nitrogen (N) content in the assimilation apparatus was considered a main factor influencing the biochemical capacity. Three experiments confirm the hypothesis that an adjustment of photosynthetic capacity under EC is controlled by the combination of biochemical, morphological, and physiological feedback mechanisms. We observed periodicity of down-regulation of photosynthetic capacity (Experiment No. 1) during the vegetation seasons. In the spring months (May-June), i.e. during the occurrence of active carbon sink associated with the formation of new foliage, up-regulation (10-35 %) of photosynthetic capacity (PNsat) was observed. On the contrary, in the autumn months (September-October) down-regulation (25-35 %) of PNsat was recorded that was mainly associated with reduced carbon sink strength and biochemical change, i.e. decrease of N status (up to 32 %) and accumulation of saccharides (up to 72 %) in leaves. Different adjustments of photosynthetic activities were observed in current (C) and one-year-old (C-1) needles exposed to EC (Experiment No. 2). Strong down-regulation of PNsat and the diminution of the initial stimulation of photosynthetic rate (PNmax) was associated with decreases of both ribulose-1,5-bisphosphate carboxylase/oxygenase carboxylation activity (by 32 %) and RuBP regeneration (by 40 %). This performance was tightly correlated with the absence of active carbon sinks, decrease of N content, and starch accumulation in C-1 needles. Finally, different responses of sun- and shade-adapted needles to EC (Experiment No. 3) were associated with the balance between morphological and biochemical changes. Observed PNsat down-regulation (by 22 %) of exposed needles in EC was predominantly caused by effects of both higher assimilate accumulation and stronger N dilution, resulting from higher absolute photosynthetic rates and incident irradiances in the upper canopy. and O. Urban ... t al.].
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

5597. Control of a class of chaotic systems by a stochastic delay method

Creator:
Zhang, Lan, Zhang, Chengjian, and Zhao, Dongming
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
random dynamical system, unified chaotic system, stochastic delay differential equations, multiplicative noise, and maximal Lyapunov exponent
Language:
English
Description:
A delay stochastic method is introduced to control a certain class of chaotic systems. With the Lyapunov method, a suitable kind of controllers with multiplicative noise is designed to stabilize the chaotic state to the equilibrium point. The method is simple and can be put into practice. Numerical simulations are provided to illustrate the effectiveness of the proposed controllable conditions.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

5598. Control of breathing and brain activation in human subjects seen by functional magnetic resonance imaging

Creator:
Václav Šmejkal, Rastislav Druga, and Jaroslav Tintěra
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Fyziologie člověka a srovnávací fyziologie, magnetická rezonance, magnetic resonance (physics), respiratory control, brain activation, 14, and 612
Language:
English
Description:
Functional magnetic resonance imaging (fMRI) was used to demonstrate the brain activation during transition from unconscious to conscious breathing in seven healthy human subjects. In right-handed volunteers, the activated areas were found in both hemispheres. The medial part of the precentral gyrus (area 4) was constantly activated in the left hemisphere. Additional activated areas were demonstrated in the premotor cortex and in the posterior parietal cortex. The activated cortical sites exhibited analogous distribution in the right hemisphere. In two out of the seven subjects, activated sites were also observed in the cerebellar hemispheres, and in the lentiform and caudate nuclei., V. Šmejkal, R. Druga, J. Tintěra., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

5599. Control of the maximal chlorophyll fluorescence yield by the QB binding site

Creator:
Prášil, Ondřej, Kolber, Z. S., and Falkowski, Paul G.
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
fotosyntéza, photosynthesis, conformational change, electron transport, photosystem II, thylakoid membrane, 2, and 581
Language:
Multiple languages
Description:
Differences in maximal yields of chlorophyll variable fluorescence (Fm) induced by single turnover (ST) and multiple turnover (MT) excitation are as great as 40%. Using mutants of Chlamydomonas reinhardtii we investigated potential mechanisms controlling Fm above and beyond the QA redox level. Fm was low when the QB binding site was occupied by PQ and high when the QB binding site was empty or occupied by a PSII herbicide. Furthermore, in mutants with impaired rates of plastoquinol reoxidation, Fm was reached rapidly during MT excitation. In PSII particles with no mobile PQ pool, Fm was virtually identical to that obtained in the presence of PSII herbicides. We have developed a model to account for the variations in maximal fluorescence yields based on the occupancy of the QB binding site. The model predicts that the variations in maximal fluorescence yields are caused by the capacity of secondary electron acceptors to reoxidize QA-., O. Prášil, Z. S. Kolber, P. G. Falkowski., and Obsahuje bibliografické odkazy
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

5600. Control of the underactuated mechanical systems using natural motion

Creator:
Neusser, Zdeněk and Valášek, Michael
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
underactuated system, nonlinear control, and mechanical systems
Language:
English
Description:
The paper deals with the control of underactuated mechanical systems between equilibrium positions across the singular positions. The considered mechanical systems are in the gravity field. The goal is to find feasible trajectory connecting the equilibrium positions that can be the basis of the system control. Such trajectory can be stabilized around both equilibrium positions and due to the gravity forces the mechanical system overcomes the singular positions. This altogether constitutes the control between the equilibrium positions. The procedure is demonstrated on the different inverse pendulum mechanisms.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

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