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792. A Lyapunov-based design tool of impedance controllers for robot manipulators
- Creator:
- Mendoza, Marco, Bonilla, Isela, Reyes, Fernando, and González-Galván, Emilio
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- impedance control, Lyapunov stability, and robot manipulator
- Language:
- English
- Description:
- This paper presents a design tool of impedance controllers for robot manipulators, based on the formulation of Lyapunov functions. The proposed control approach addresses two cha\-llen\-ges: the regulation of the interaction forces, ensured by the impedance error converging to zero, while preserving a suitable path tracking despite constraints imposed by the environment. The asymptotic stability of an equilibrium point of the system, composed by full non\-li\-near robot dynamics and the impedance control, is demonstrated according to Lyapunov's direct method. The system's performance was tested through the real-time experimental implementation of an interaction task involving a two degree-of-freedom, direct-drive robot.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
793. A Maschke type theorem for relative Hom-Hopf modules
- Creator:
- Guo, Shuangjian and Chen, Xiu-Li
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- monoidal Hom-Hopf algebra, separable functors, Maschke type theorem, total integral, and relative Hom-Hopf module
- Language:
- English
- Description:
- Let $(H,\alpha )$ be a monoidal Hom-Hopf algebra and $(A,\beta )$ a right $(H,\alpha )$-Hom-comodule algebra. We first introduce the notion of a relative Hom-Hopf module and prove that the functor $F $ from the category of relative Hom-Hopf modules to the category of right $(A, \beta )$-Hom-modules has a right adjoint. Furthermore, we prove a Maschke type theorem for the category of relative Hom-Hopf modules. In fact, we give necessary and sufficient conditions for the functor that forgets the $(H, \alpha )$-coaction to be separable. This leads to a generalized notion of integrals.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
794. A mathematical model for the recovery of human and economic activities in disaster regions
- Creator:
- Kadoya, Atsushi and Kenmochi, Nobuyuki
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- economic growth, human activity, economic activity, and system of ordinary differential equations
- Language:
- English
- Description:
- In this paper a model for the recovery of human and economic activities in a region, which underwent a serious disaster, is proposed. The model treats the case that the disaster region has an industrial collaboration with a non-disaster region in the production system and, especially, depends upon each other in technological development. The economic growth model is based on the classical theory of R. M. Solow (1956), and the full model is described as a nonlinear system of ordinary differential equations.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
795. A mathematical model of rat ventricular cardiomyocyte with a novel description of intracellular and t-tubular Ca2+ dynamics
- Creator:
- Pásek, Michal and Šimurda, Jiří
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- cardiac cell, intracellular Ca2+ dynamics, t-tubule, and quantitative modelling
- Language:
- English
- Description:
- In this paper, we present a novel quantitative description of intracellular and t-tubular Ca2+ dynamics in a model of rat cardiac ventricular myocyte. In order to simulate recently published data, the model incorporates t-tubular and peripheral dyads and intracellular subspaces, segmentation of the t-tubular luminal volume, reformulation of the inactivation properties of t-tubular land peripheral L-type calcium current (ICa) and a description of exogenous Ca2q+ buffer function in the intracellular space. The model is used to explore activity-induced changes of ion concentration in the intracellular and t-tubular spaces and their role in excitation - contraction coupling in ventricular myocytes. and Obsahuje Appendix se seznamy literatury, užitých zkratek a symbolů
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
796. A measure-theoretic characterization of the Henstock-Kurzweil integral revisited
- Creator:
- Lee, Tuo-Yeong
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Henstock variational measure and Henstock-Kurzweil integral
- Language:
- English
- Description:
- In this paper we show that the measure generated by the indefinite Henstock-Kurzweil integral is $F_{\sigma \delta }$ regular. As a result, we give a shorter proof of the measure-theoretic characterization of the Henstock-Kurzweil integral.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
797. A Mediterranean population of Pyrrhocoris apterus (Heteroptera: Pyrrhocoridae) exhibits wing morph-related differences in adipokinetic response
- Creator:
- Kodrík, Dalibor and Socha, Radomír
- Format:
- print, text, and regular print
- Type:
- article, bibliography, model:article, and TEXT
- Subject:
- zoologie, entomologie, hmyz, ploštice, Pyrrhocoridae, Pyrrhocoris apterus, křídla, dimorfismus křídel, neurohormony, adipokinetické hormony, funkce, 595.2/.7, and 591.1
- Language:
- English
- Description:
- Short-winged (brachypterous) and long-winged (macropterous) adult females of Pyrrhocoris apterus (L.) originating from a Mediterranean population (Israel) were analyzed for their adipokinetic responses. The adipokinetic response, expressed as an increase of haemolymph lipids after injection of adipokinetic hormone from Locusta migratoria (Lom-AKH-I), was assessed in relation to age and dose of the hormone. We demonstrate in this study that the adipokinetic responses induced by bug's corpora cardiaca extract and Lom-AKH-I were dose-dependent for both brachypterous and macropterous females. Significant differences between the morphs were recorded for doses >= 0.25 corpora cardiaca equivalent (P < 0.01) and doses >= 0.25 pmol Lom-AKH-I (P < 0.05). The haemolymph lipid elevations induced in both morphs by 2 pmols Lom-AKH-I are comparable with that induced by crude extract of one pair of the bug's own corpora cardiaca. The age-dependent test showed much higher adipokinetic responses (P < 0.01) in macropterous females (>= 5 days old) than in the brachypterous females of the same age, when treated with 2 pmols Lom-AKH-I. Starting from day 7, the concentration of haemolymph lipids was also considerably higher (2.5-5 times) in macropterous females than in the brachypterous ones. The obtained data indicate that difference in mobilization of lipids between brachypterous and macropterous females is a geographically independent feature and represents a true wing morph characteristic of P. apterus., Dalibor Kodrík, Radomír Socha, and Lit
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
798. A mesomechanical analysis of creep under different time-independent loadings
- Creator:
- Kafka, Vratislav
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- creep, mesomechanics, and tensorial internal variables
- Language:
- English
- Description:
- The general author‘s mesomechanical model with tensorial internal variables is applied to creep of steel 0,5Cr0,5Mo0,3V under different loading levels. It is shown that the creep process can be described by the mesomechanical model in its whole course up to rupture. However, the model parameters can be influenced at the very beginning by the application of the applied load if it is high enough to cause changes in the internal structure. This problem is specific for creep at high temperatures and significant differences in the loading levels (contrary to the small-strain plasticity studied usually at low temperatures, where the model parameters can be considered the same for different loadings). and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
799. A method for determination of one hundred endogenous steroids in human serum by gas chromatography-tandem mass spectrometry
- Creator:
- Hill, M. , Hána, V. , Velíková, M., Pařízek, A., Kolátorová, L. , Vítků, J., Škodová, T., Šimková, M. , Šimják, P. , Kancheva, R., Koucký, M. , Kokrdová, Z., Adamcová, K. , Černý, A. , Hájek, Z., Dušková, M., Bulant, J., and Stárka, L.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Steroid metabolome, Human blood, Gas chromatographytandem mass spectrometry, Backdoor pathway, Pregnancy, and Mixed umbilical cord blood
- Language:
- English
- Description:
- Steroid profiling helps various pathologies to be rapidly diagnosed. Results from analyses investigating steroidogenic pathways may be used as a tool for uncovering pathology causations and proposals of new therapeutic approaches. The purpose of this study was to address still underutilized application of the advanced GC-MS/MS platform for the multicomponent quantification of endogenous steroids. We developed and validated a GC-MS/MS method for the quantification of 58 unconjugated steroids and 42 polar conjugates of steroids (after hydrolysis) in human blood. The present method was validated not only for blood of men and non-pregnant women but also for blood of pregnant women and for mixed umbilical cord blood. The spectrum of analytes includes common hormones operating via nuclear receptors as well as other bioactive substances like immunomodulatory and neuroactive steroids. Our present results are comparable with those from our previously published GC-MS method as well as the results of others. The present method was extended for corticoids and 17α-hydroxylated 5α/β-reduced pregnanes, which are useful for the investigation of alternative “backdoor” pathway. When comparing the analytical characteristics of the present and previous method, the first exhibit by far higher selectivity, and generally higher sensitivity and better precision particularly for 17α-hydroxysteroids.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
800. A method for measuring coalbed methane content in coal strata without the loss of the gas
- Creator:
- Nazimko , Victor
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- coal strata, coalbed methane, exploration, gas content, measurement, lost gas, and coal mine safety
- Language:
- English
- Description:
- This paper describes an invented method for direct measurement of coalbed methane content in situ. In contrast to known procedures, this method does not need to place a rock or drilling cuts into an airtight canister, and does not involve sealing of the hole. Moreover, the new method is monitoring methane content in situ continuously and synchronously during drilling the hole not losing any portion of the gas. These positive features are a sequel of new approach based on injection of known portion of neutral gas into the hole. Methane content was determined from concentration of the mixture ‘methane-neutral gas´ at the hole´s mouth. New method is applicable for commercial recovery application of coalbed methane and forecast of dangerous gas and coal bursts. FLAC3D computer simulation helped to investigate dynamics of methane outflow from the hole to account for the effect of drilling speed on the rate of gas emanation.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public