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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

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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： Autoimmune pancreatitis Serum immunoglobulin G4 level Systemic lupus erythematosus Sj gren’s syndrome Mikulicz’s disease

Harmonics in the Squirrel Cage Induction Motor Analytic Calculation Part III: Influence on the Torque-speed Characteristic

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CES Transactions on Electrical Machines and Systems 2024年第1期8卷 86-102页

作者： G.kovács the Ganz Electric Works BudapestHungary

The harmonics that appear in the squirrel cage asynchronous machine have been discussed in great detail in the literature for a long time. However, the systematization of the phenomenon is still pending, so we made an attempt to fill this gap in the previous parts of our study by elaborating formulas for calculation of parasitic torques. It was a general demand among those who work in this field towards the author to verify his formulas with measurements. In the literature, it seems,only one detailed, purposeful series of measurements has been published so far, the purpose of which was to investigate the effect of the number of rotor slots on the torque-speed characteristic curve of the machine. The main goal of this study is to verify the correctness of the formulas by comparing them with the referred series of measurements. Relying on this, the expected synchronous parasitic torques were developed for the frequently used rotor slot numbers-as a design guide for the ***, together with our complete table for radial magnetic pull published in our previous work, the designer has all the principles, data and formulas available for the right number of rotor slots for his given machine and for the drive system. This brings this series of papers to an end.

关键词： Asynchronous parasitic torques Induction motor Squirrel cage rotor Space harmonics Synchronous parasitic torques

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Genetic defects in ciliary genes in autosomal dominant polycystic kidney disease

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World Journal of Nephrology 2018年第2期7卷 65-70页

作者： Katarína Skalická Gabriela Hrcková Anita Vaská Agnes Baranyaiová lászlókovács laboratory of Clinical and Molecular Genetics Department of PaediatricsFaculty of MedicineComenius University and University Children’s HospitalBratislava 83340Slovakia

AIM To evaluate the genetic defects of ciliary genes causing the loss of primary cilium in autosomal dominant polycystic kidney disease(ADPKD). METHODS We analyzed 191 structural and functional genes of the primary cilium using next-generation sequencing analysis. We analyzed the kidney samples, which were obtained from 7 patients with ADPKD who underwent nephrectomy. Each sample contained polycystic kidney tissue and matched normal kidney tissue. RESUlTS In our study, we identified genetic defects in the 5 to 15 genes in each ADPKD sample. The most frequently identified defects were found in genes encoding centrosomal proteins (PCM1, ODF2, HTT and CEP89) and kinesin family member 19 (KIF19), which are important for ciliogenesis. In addition, pathogenic mutations in the PCM1 and KIF19 genes were foundin all ADPKD samples. Interestingly, mutations in the genes encoding the intraflagellar transport proteins, which are the basis of animal models of ADPKD, were only rarely detected. CONClUSION The results of our study revealed the actual state of structural ciliary genes in human ADPKD tissues and provided valuable indications for further research.

关键词： Polycystic kidney disease Primary cilium Ciliary genes Next-generation sequencing Genetic variants

Recent Advances in Catalytic Carbonylation Reactions in Alternative Reaction Media

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Chinese Journal of Chemistry 2024年第4期42卷 406-429页

作者： csaba Árvai lászló T.Mika Department of Chemical and Environmental Process Engineering Faculty of Chemical Technology and BiotechnologyBudapest University of Technology and EconomicsMűegyetem rkp.3H-1111 BudapestHungary

Since the discovery of the hydroformylation(oxo-synthesis or Roelen reaction)and the Reppe-reaction,the transition metal-catalyzed carbonylation reactions,providing versatile,facile,and even atom-economic methods for the selective incorporation of C=O functionality to various skeletons,have gained tremendous importance in synthetic organic chemistry from laboratories to industrial *** carbonylation of carbon-carbon multiple bonds,aromatic halides,triflates,etc.,in the presence of various nucleophiles has led the way to produce aldehydes,carboxylic acids,esters,amides,etc.,in the fine chemical ***,these protocols usually proceed in conventional,fossil-based,and usually toxic reaction ***,several attempts have been directed to developing efficient carbonylation methods in alternative,less harmful,non-fossil-based and even in renewable reaction *** this review,we overview the recent applications of alternative solvents such as water,biomass-based alcohols,γ-valerolactone(GVl),2-methyltetrahydrofuran(2-MeTHF),ionic liquids(Ils),deep eutectic solvents(DES),alkyl levulinates,limonene,α-pinene,and dimethyl carbonate as well as fluorous media to improve efficiency,safety and environmentally benign nature of carbonylation protocols.

关键词： Carbonylation Catalysis Solvents Green chemistry Carbon monoxide Transition metals Homogeneous catalysis Palladium

Enabling Technologies for Autonomous Robotic Systems in Manufacturing

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Transactions of Nanjing University of Aeronautics and Astronautics 2024年第4期41卷 403-431页

作者： ERDŐS Gábor ABAI Kristóf BEREGI Richárd csEMPESZ János csERTEG Tamás GODÓGábor HAJÓS Mátyás HÁY Borbála HORVÁTH Dániel HORVÁTH Gergely JUNIKIÁdám KEMÉNY Zsolt kovÁcs András NAcsA János PANITI Imre PEDONE Gianfranco TAKÁcs Emma TIPARY Bence ZAHORÁN lászló VÁNCZA József Institute for Computer Science and Control Hungarian Research Network(HUN-REN SZTAKI)BudapestHungary Department of Manufacturing Science and Technology Budapest University of Technology and Economics(BME)BudapestHungary EPIC Innolabs Nonprofit ltd. BudapestHungary Eötvös loránd University(ElTE) BudapestHungary

Research of autonomous manufacturing systems is motivated both by the new technical possibilities of cyber-physical systems and by the practical needs of the *** operation in semi-structured industrial environments can now be supported by advanced sensor technologies,digital twins,artificial intelligence and novel communication *** enable real-time monitoring of production processes,situation recognition and prediction,automated and adaptive(re)planning,teamwork and performance improvement by *** paper summarizes the main requirements towards autonomous industrial robotics and suggests a generic workflow for realizing such *** case studies will be presented from recent practice at HUN-REN SZTAKI in a broad range of domains such as assembly,welding,grinding,picking and placing,and *** various solutions have in common that they use a generic digital twin concept as their *** making general recommendations for realizing autonomous robotic solutions in the industry,open issues for future research will be discussed.

关键词： industrial robotics autonomy digital twin enabling technology

Nonstationary laser-supported ionization wave in layer of porous substance with subcritical density

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Matter and Radiation at Extremes 2024年第1期9卷 58-70页

作者： S.Yu Gus’kov R.A.Yakhin P.N.lebedev Physical Institute of Russian Academy of Sciences Leninskii Prospect 53Moscow 119991Russia

A time-dependent analytical solution is found for the velocity of a plane ionization wave generated under nanosecond laser pulse action on the surface of a flat layer of low-Z porous substance with density less than the critical density of the produced *** corrections for the two-dimensional nature of the problem when a laser beam of finite radius interacts with a flat target,this solution is in quantitative agreement with measurements of ionization wave velocity in various *** solution compared with experimental data covering wide ranges of performance conditions,namely,(3-8)×10^(14)W cm^(−2)for laser pulse intensity,0.3-3 ns for pulse duration,0.35-0.53μm for laser wavelength,100-1000μm for laser beam radius,380-950μm for layer thickness,4.5-12 mg cm^(−3)for average density of porous substance,and 1-25μm for average pore *** parameters of the laser beam that ensure the generation of a plane ionization wave in a layer of subcritical porous matter are determined for the problem statements and are found to meet the requirements of practical applications.

关键词： laser pulse porous

Development of an ultrathin liquid sheet target for laser ion acceleration at high repetition rates in the kilohertz range

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High Power laser Science and Engineering 2024年第3期 139-150页

作者： M.Füle A.P.kovács T.Gilinger M.Karnok P.Gaál S.Figul G.Marowsky K.Osvay National laser-Initiated Transmutation laboratory University of Szeged Department of Experimental Physics University of Szeged ElI AlPS ELI-HU Non-Profit Ltd. Department of Optics and Quantum Electronics University of Szeged Advanced Microfluidic Systems GmbH

A colliding microjet liquid sheet target system was developed and tested for pairs of round nozzles of 10, 11 and 18 μm in diameter. The sheet's position stability was found to be better than a few micrometers. Upon interaction with 50 mJ laser pulses, the 18 μm jet has a resonance amplitude of 16 μm at a repetition rate of 33 Hz, while towards 100 Hz it converges to 10 μm for all nozzles. A white-light interferometric system was developed to measure the liquid sheet thickness in the target chamber both in air and in vacuum, with a measurement range of 182 nm±1 μm and an accuracy of±3%. The overall shape and 3D shape of the sheet follow the Hasson±Peck model in air. In vacuum versus air, the sheet gradually loses 10% of its thickness, so the thinnest sheet achieved was below 200 nm at a vacuum level of 10±4mbar,and remained stable for several hours of operation.

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How to explore a new environment:exploratory tactics of the black rat(Rattus rattus)

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Current Zoology 2024年第3期70卷 371-382页

作者： Iveta Štolhoferová Veronika Rudolfová Hana Skalíková Barbora Vobrubová Daniel Frynta Department of Zoology Faculty of ScienceCharles UniversityViničná712843 Prague 2Czechia

The black rat(Rattus rattus)is a unique model for studying exploratory tactics due to its enormous colonizing *** behavioral variability and consistent interindividual differences might help populations inhabit new environments and persist there even under intense ***,the affnity of the black rat for climbing might be another advantage,widening their potential *** this study,we describe the exploratory tactics of the black rats when introduced to a novel *** the frst experiment,we tested 12 rats and calculated repeatability of their behaviors across 12 sessions of an enriched open-feld *** concluded that climbing is a highly repeatable behavior that serves as an important source of interindividual *** the second experiment,we tested 24 black rats in a unique l-shaped *** rat was tested *** found that the majority of rats distributed their activity evenly,exploring each part of the apparatus for a similar amount of time,thus maximizing their chances of fnding ***,these“even”explorers still greatly differed in their level of activity,orderliness and affnity for climbing,generating large *** contrast,the minority of rats concentrated their activity only on a section of the new environment and were therefore characterized as selective ***,we concluded that a combination of such exploratory tactics as well as a bias for even explorers enables black rats to quickly colonize new environments and persist there even under unfavorable conditions.

关键词： 3D behavior climbing repeatability strategy.