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stability case study of the ACROBOTER underactuated service robot

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Theoretical & Applied Mechanics Letters 2012年第4期2卷 27-33页

作者： László L.kovács László Bencsik HAs-BME Research Group on Dynamics of Machines and Vehicles Budapest H-1521Hungary Department of Applied Mechanics Budapest University of Technology and EconomicsBudapest H-1521Hungary

The dynamics of classical robotic systems are usually described by ordinary differential equations via selecting a minimum set of independent generalized coordinates. However, different parameterizations and the use of a nonminimum set of （dependent） generalized coordinates can be advantageous in such cases when the modeled device contains closed kinematic loops and/or it has a complex structure. On one hand, the use of dependent coordinates, like natural coordinates, leads to a different mathematical representation where the equations of motion are given in the form of differential algebraic equations. On the other hand, the control design of underactuated robots usually relies on partial feedback linearization based techniques which are exclusively developed for systems modeled by independent coordinates. In this paper we propose a different control algorithm formulated by using dependent coordinates. The applied computed torque controller is realized via introducing actuator constraints that complement the kinematic constraints which are used to describe the dynamics of the investigated service robotic system in relatively simple and compact form. The proposed controller is applied to the computed torque control of the planar model of the ACROBOTER service robot. The stability analysis of the digitally controlled underactuated service robot is provided as a real parameter case study for selecting the optimal control gains.

关键词： stability underactuation natural coordinates control constraints

Antioxidant efficiency of lycopene on oxidative stress-induced damage in bovine spermatozoa

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Journal of Animal science and Biotechnology 2017年第1期8卷 67-79页

作者： Eva Tvrdá Anton kovácik Eva Tusimová Dusan Paál Alica Mackovich Jakhongir Alimov norbert Lukác Department of Animal Physiology Faculty of Biotechnology and Food Sciences Slovak University of Agriculture in Nitra Tr. A. Hlinku 2 Nitra 94976 Slovakia AgroBioTech Research Centre Slovak University of Agriculture in Nitra Tr. A. Hlinku 2 Nitra 94976 Slovakia Department of Botany and Genetics Faculty of Natural Sciences Constantine the Philosopher University in Nitra Nabbrezie mladeze 91 Nitra 94974 Slovakia Department of General Biology Faculty of Natural Sciences Gulistan State University 4th Microrayon Guliston 120100 Syrdarya Uzbekistan.

Background： Lycopene（LYC） is a natural carotenoid with powerful reactive oxygen species（ROs） scavenging activities. The aim of this study was to investigate if lycopene has the ability to reverse ROs-mediated alterations to the motility, viability and intracellular antioxidant profile of bovine spermatozoa subjected to ferrous ascorbate（Fe AA）. spermatozoa were washed out of fresh bovine semen, suspended in 2.9 % sodium citrate and subjected to LYC treatment（0.25, 0.5, 1 or 2 mmol/L） in the presence or absence of Fe AA（150 μmol/L Fe sO4 and 750 μmol/L ascorbic acid） during a 6 h in vitro culture. spermatozoa motion characteristics were assessed using the sperm Vision？computer-aided sperm analysis（CAsA） system. Cell viability was examined with the metabolic activity（MTT） assay,ROs generation was quantified via luminometry and the nitroblue-tetrazolium（nBT） test was applied to quantify the intracellular superoxide formation. Cell lysates were prepared at the end of the in vitro culture to investigate the intracellular activity of superoxide dismutase（sOD）, catalase（CAT）, glutathione peroxidase（GPx） as well as the concentrations of glutathione（GsH） and malondialdehyde（MDA）.Results： FeA A treatment led to a reduced spermatozoa motility（P 〈 0.001）, viability（P 〈 0.001） and a decline of the antioxidant capacity of spermatozoa（P 〈 0.001） but increased the ROs generation（P 〈 0.001）, superoxide production（P 〈 0.001） and lipid peroxidation（P 〈 0.001）. LYC administration resulted in a preservation of the spermatozoa motion parameters（P 〈 0.001）, mitochondrial activity（P 〈 0.001） and antioxidant characteristics（P 〈 0.001 with respect to sOD;P 〈 0.01 in relation to CAT; P 〈 0.05 as for GPx and GsH） with a concentration range of 1 and 2 mmol/L LYC revealed to be the most ***： Our results suggest that LYC exhibits significant ROs-scavenging and antioxidant properties which may prevent spermatozoa alterations caused by oxidative stress, and preserve the functional

关键词： Antioxidants Bulls Ferrous ascorbate Lycopene Oxidative stress spermatozoa

Comparison with Molecular surface Electrostatic Potential and Thermal Reactivity of nitramines

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含能材料 2015年第12期23卷 1155-1161页

作者： svatopluk Zeman Zdenek Friedl Monika Bartoskova Qi-Long YAn Institute of Energetic Materials Faculty of Chemical TechnologyUniversityo f PardubiceCZ-53210PardubicetheCzechRepublic Facultyof Chemistry Brno Universityof TechnologyCZ.-61200Brnothe Czech Republic

Molecular surface electrostatic potentials V_s(r) ( EsP) of seventeen nitramines have been calculated. As a criterion of the imbalance between the maximum positive,V_(s,max) and minimum negative,V_(s,min),values of molecular surface electrostatic potentials their sum was derived and used as a new simple characteristic for EsPs-V_(s,Σ). These V_(s,Σ) values have close relationships with the Arrhenius parameters,activation energy E_a and preexponent log A,of thermal decomposition of the nitramines studied. The correlation between the V_(s,Σ) values and heats of fusion of the nitramines studied is described. These findings suggested analyzing the physico-chemical behavior of the nitramine crystals during this decomposition; in this connection an investigation was carried out using isothermal thermogravimetry and scanning electron microscopy of thermally exposed crystals of cis-1,3,4,6-tetranitrooctahydroimidazo-[4,5-d]imidazole( sintering of its crystal surfaces),of β-1,3,5,7-tetranitro-1,3,5,7-tetrazocane( cracking of its crystals during β !δ transition) and of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane. The results suggest a need to study the pre-decomposition states on thermal decomposition of the nitramines' molecule's crystals.

关键词：爆破器料含能材料材料烟火材料

Analysis of shower particle pseudorapidity spectra in interactions of relativistic Au and Pb ions with emulsion nuclei

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Chinese Physics C 2011年第12期35卷 1095-1099页

作者： B.Z.Belashev M.K.suleymanov s.Vokál J.Vrláková M.Ajaz Ali Zaman K.H.Khan Z.Wazir Institute of Geology Karelian Research Center Russian Academy of Sciences St. Petrozavodsk Russia COMsATs Institute of Information Technology Department of Physics Islamabad 44000 Pakistan Veksler and Baldin Laboratory of High Energy Physics JINR Dubna 141980 Russia P. J. afárik University Koice Slovakia

The pseudorapidity spectra of fast particles （with β 〉 0.7） produced in Au （at 11.6 A GeV） and Pb （at 158 A GeV） induced collisions with emulsion （Em） nuclei contain some visual plateaus and shoulders. The plateau is wider for Pb＋Em reactions compared with the Au＋Em ones. The existence of a plateau is expected for parton models. The Fourier transformation and maximum entropy methods were used to get additional information about the plateaus. The dependence of the plateaus on the centrality of the collisions was also studied using the number of g-particles to fix centrality. It shows that the maximum entropy method could confirm the existence of the plateau and the shoulder on distributions.

关键词： pseudorapidity spectra s-particles g-particles centrality Fourier transformation maximum entropy

Cavitation and grain boundary sliding during creep of Mg-Y-nd-Zn-Mn alloy

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中国有色金属学会会刊：英文版 2008年第A1期18卷 64-68页

作者： V.JAníK F.HnILICA P.ZUnA V.OEnEK I.sTULíkov Department of Materials Engineering Faculty of Mechanical EngineeringCzech Technical University in PraguePragueCzech Republic Research Institute for Metals Panenské BrezanyCzech Republic Faculty of Mathematics and Physics Charles UniversityPragueCzech Republic

Creep of squeeze-cast Mg-3Y-2nd-1Zn-1Mn alloy was investigated at the constant load in the stress range of 30-80 MPa. Tensile creep tests were performed at 300℃up to the final *** tests at 50 MPa were interrupted after reaching the steady state creep;and another set of creep tests was interrupted after the onset of ternary *** of cavitated dendritic boundaries was evaluated using optical *** of grain boundary sliding by observation of the offset of marker lines was carried out on the surface of the crept specimens after the test interruption by scanning electron microscopy and by confocal laser scanning *** results show that the dominant creep mechanism in this alloy is dislocation creep with minor contribution of the grain boundary *** failure took place by the nucleation,growth and coalescence of creep cavities on the boundaries predominantly oriented perpendicular to the applied *** amount of cavitated boundaries with time of creep exposure supports the mechanism of continuous cavity nucleation and growth.

关键词：镁合金锌合金锰合金高温测试

Morphological characteristics of blood cells in monitor lizards:is erythrocyte size linked to actual body size?

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Integrative Zoology 2013年第1期8卷 39-45页

作者： Petra FRÝDLOVÁ Jan HnÍZDO Lenka CHYLÍkovÁ OlgaŠIMkovÁ Veronika CIKÁnOVÁ Petr VELEnsKÝ Daniel FRYnTA Department of Zoology Charles University in PraguePragueCzech Republic Animal Clinic PragueCzech Republic Prague Zoo PragueCzech Republic

Blood cell morphology and count are not uniform across ***,between-species comparisons revealed that the size of red blood cells is associated with body size in some lizard taxa,and this finding was interpreted in the context of the metabolic *** the present study,we examined the numbers and the size of blood cells in 2 species of monitor lizards,the mangrove-dwelling monitor(Varanus indicus)and the savannah monitor(***),and we compared these traits in individuals of different body *** results revealed that during the course of ontogeny,the size of red blood cells increases with body *** the mass-specific metabolic rate decreases with body size and the cell volume-to-surface ratio decreases with the cell size,changes in the erythrocyte size might be the result of oxygen transport adjustment.

关键词： blood parameters body size erythrocyte size metabolic theory Varanidae

Words apart:standardizing forestry terms and definitions across European biodiversity studies

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森林生态系统:英文版 2023年第4期10卷 459-471页

作者： Giovanni Trentanovi Thomas Campagnaro Tommaso sitzia Francesco Chianucci Giorgio Vacchiano Christian Ammer MichałCiach Thomas Anagel Miren del Río Yoan Paillet silvana Munzi Kris Vandekerkhove Andrés Bravo-Oviedo Andrea Cutini Ettore D'Andrea Pallieter De smedt Inken Doerfler Dimitris Fotakis Jacob Heilmann-Clausen Jeňýk Hofmeister Jan Hošek Philippe Janssen sebastian Kepfer-Rojas nathalie Korboulewsky Bence kovács Daniel Kozák Thibault Lachat Anders Mårell Radim Matula Martin Mikoláš Björn nordén PéterÓdor x Marko Perović Elisabeth Pötzelsberger Peter schall Miroslav svoboda Flóra Tinya Mariana Ujházyová sabina Burrascano Research Institute on Terrestrial Ecosystems-national Research Council(IRET-CnR) Via Madonna Del Piano 1950019Sesto FiorentinoFIItaly Department of Land EnvironmentAgriculture and ForestryUniversitàdegli Studi di PadovaViale Dell’Università1635020LegnaroPDItaly national Biodiversity Future Center Piazza Marina 6190133PalermoItaly CREA Research Centre for Forestry and Wood Viale S.Margherita 8052100ArezzoItaly Department of Agricultural and Environmental sciences(DIsAA) University of MilanVia Celoria 220133MilanItaly silviculture and Forest Ecology of the Temperate Zones University of GöttingenGermany Department of Forest Biodiversity Faculty of ForestryUniversity of Agricultureal.29 Listopada 4631-425KrakówPoland Department of Forestry and Renewable Forest Resources Biotechnical FacultyUniversity of LjubljanaVecna pot 831000LjubljanaSlovenia Instituto de Ciencias Forestales(ICIFOR-InIA) CSICCtra.de la Coruña Km 7.528040MadridSpain University Grenoble Alpes LessemINRAE2 Rue de la Papeterie38402 Saint-Martin-d'HèresFrance Centro Interuniversitário de História Das Ciências e da Tecnologia Faculdade de CiênciasUniversidade de LisboaPortugal Centre for Ecology Evolution and Environmental ChangesFaculdade de Ciências&CHANGE-Global Change and Sustainability InstituteUniversidade de LisboaPortugal Research Institute for nature and Forest(InBO) Havenlaan 88 Bus 731000BrusselBelgium Department of Biogeography and Global Change National Museum of Natural Sciences-CSICC/Serrano 115bis28006MadridSpain Research Institute on Terrestrial Ecosystems-national Research Council(IRET-CnR) Via G.Marconi N.205010PoranoTRItaly Forest&nature Lab Department of EnvironmentGhent UniversityGeraardsbergsesteenweg 2679090GontrodeBelgium Institute of Biology and Environmental science Vegetation Science&Nature ConservationUniversity of OldenburgAmmerländer Heerstraße 114-11826129OldenburgGermany Forest Research Institute Hellenic Agricultural Organization DimitraVassilikaThessal

Forest biodiversity studies conducted across Europe use a multitude of forestry terms,often *** hinders the comparability across studies and makes the assessment of the impacts of forest management on biodiversity highly *** attempts to standardize forestry and stand description terminology mostly used a top-down approach that did not account for the perspectives and approaches of forest biodiversity *** work aims to establish common standards for silvicultural and vegetation definitions,creating a shared conceptual framework for a consistent study on the effects of forest management on *** have identified both strengths and weaknesses of the silvicultural and vegetation information provided in forest biodiversity *** quantitative data on forest biomass and dominant tree species are frequently included,information on silvicultural activities and vegetation composition is often lacking,shallow,or based on broad and heterogeneous *** discuss the existing classifications and their use in European forest biodiversity studies through a novel bottom-up and top-driven review process,and ultimately propose a common *** will enhance the comparability of forest biodiversity studies in Europe,and puts the basis for effective implementation and monitoring of sustainable forest management *** standards here proposed are potentially adaptable and applicable to other geographical areas and could be extended to other forest interventions.

关键词： Forest management Multi-taxon Terminology silviculture Data harmonization

Association between autoimmune pancreatitis and systemic autoimmune diseases

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World Journal of Gastroenterology 2012年第21期18卷 2649-2653页

作者： Viktória Terzin Imre Fldesi László kovács Gyula Pokorny Tibor Wittmann László Czakó First Department of Medicine University of SzegedH-6701 Szeged Hungary Department of Rheumatology University of SzegedH-6701 Szeged Hungary

AIM: To investigate the association between autoimmune pancreatitis (AIP) and systemic autoimmune diseases (sAIDs) by measurement of serum immunoglobulin G4 (IgG4). METHODs: The serum level of IgG4 was measured in 61 patients with sAIDs of different types who had not yet participated in glucocorticosteroid treatment. Patients with an elevated IgG4 level were examined by abdominal ultrasonography (Us) and, in some cases, by computer tomography (CT). REsULTs: Elevated serum IgG4 levels (919 ± 996 mg/L) were detected in 17 (28%) of the 61 sAID patients. 10 patients had sj gren's syndrome (ss) (IgG4: 590 ± 232 mg/L), 2 of them in association with Hashimoto's thyroiditis, and 7 patients (IgG4: 1388 ± 985.5 mg/L) had systemic lupus erythematosus (sLE). The IgG4 level in the sLE patients and that in patients with ss were not significantly different from that in AIP patients (783 ± 522 mg/L). Abdominal Us and CT did not reveal any characteristic features of AIP among the sAID patients with an elevated IgG4 level. COnCLUsIOn: The serum IgG4 level may be elevated in sAIDs without the presence of AIP. The determination of serum IgG4 does not seem to be suitable for the differentiation between IgG4-related diseases and sAIDs.

关键词：自身免疫性疾病系统性红斑狼疮胰腺炎血清免疫球蛋白关联计算机断层扫描 AIP 激素治疗

Contribution of Good Agricultural Practices to soil Biodiversity

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Open Journal of Ecology 2021年第1期11卷 75-85页

作者： Beata Houšková Rastislav Bušo Jarmila Makovníková national Agricultural and Food Centre/soil science and Conservation Research Institute Bratislava Slovakia national Agricultural and Food Centre/VÚ RV Pie&#353 ť any Slovakia national Agricultural and Food Centre/soil science and Conservation Research Institute Banská Bystrica Slovakia

At present time when climate change has negative effect on soil moisture and can decrease significantly the productivity, good agricultural practises have a high importance via their direct influence on soil properties, regimes and biodiversity. Objectives of this study have been focused on the assessment of good agricultural practises in different soil cultivation types: conventional, minimum till, mulch, no-till and organic farming. Method used was based on two case study areas where organic and/or minimal farming systems have been applied. As a control, we chose soil with traditional cultivation. In organic farm, we evaluated earthworms;their amount and status and in farm with different types of cultivation we evaluated the microbial activity to assess the biodiversity conditions. Basic soil properties and soil structure have been set to be able to assess the influence of good agricultural practises on soil environment. Our study shows positive effect of these practises on soil moisture content, biodiversity and soil structure stability. These findings can be used for further studies determining the ways of soil cultivation in harmony with nature—in sustainable way.

关键词： Good Agricultural Practices soil Biodiversity Earthworms Microorganisms soil Enzymes Organic Farm soil Moisture