Search results for "75"

showing 10 items of 1365 documents

Optimal passive-damping design using a decentralized velocity-feedback H-infinity approach

2012

In this work, a new strategy to design passive energy dissipation systems for vibration control of large structures is presented. The method is based on the equivalence between passive damping systems and fully decentralized static velocity-feedback controllers. This equivalence allows to take advantage of recent developments in static output-feedback control design to formulate the passive-damping design as a single optimization problem with Linear Matrix Inequality constraints. To illustrate the application of the proposed methodology, a passive damping system is designed for the seismic protection of a five-story building with excellent results. Peer Reviewed

Work (thermodynamics)EngineeringOptimization problemDecentralized controlStructural Vibration Control:Informàtica::Automàtica i control [Àrees temàtiques de la UPC]Static output-feedbackVibration control:Enginyeria civil::Materials i estructures [Àrees temàtiques de la UPC]Feedback control systemsMatrius (Matemàtica)lcsh:QA75.5-76.95Structural vibration controlControl d'estructures (Enginyeria):93 Systems Theory; Control [Classificació AMS]Control theoryControlMatrix inequalitiesEquivalence (measure theory):93 Systems Theory [Classificació AMS]business.industryOptimal passive dampingLinear matrix inequalityControl engineeringDissipationDecentralised systemComputer Science ApplicationsH-infinity methods in control theoryControl and Systems EngineeringModeling and SimulationSistemes de control per retroacciólcsh:Electronic computers. Computer scienceStructural control (Engineering)businessSoftware
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First observations of the X-ray transient EXO 2030+375 with IBIS/ISGRI

2003

We present a first INTEGRAL observation of the 42s transient X-ray pulsar EXO 2030+375 with IBIS/ISGRI. The source was detected during Cyg X-1 observations in December 2002. We analyzed observations during the outburst period from 9 to 21 December 2002 with a total exposure time of ~770 kiloseconds. EXO 2030+375 was almost always detected during single ~30 minute exposures in the 18-45 energy bands. The source light curve shows the characteristic outburst shape observed in this source.

X-ray transientFOS: Physical sciencesIndividualAstrophysicsUNESCO::ASTRONOMÍA Y ASTROFÍSICAAstrophysicsGamma rays ; Observations ; X-rays ; Individual ; EXO 2030+375 ; Telescopes ; INTEGRAL ; IBISPulsarX-raysObservations:ASTRONOMÍA Y ASTROFÍSICA::Astronomía óptica [UNESCO]PhysicsIbisEXO 2030+375biologyINTEGRALUNESCO::ASTRONOMÍA Y ASTROFÍSICA::Astronomía ópticaGamma raysAstrophysics (astro-ph)Astronomy and Astrophysicsbiology.organism_classificationLight curveSpace and Planetary ScienceIBIS:ASTRONOMÍA Y ASTROFÍSICA [UNESCO]Telescopes
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Zvaigžņotā Debess: 2009, Vasara (204)

2009

Contents: E.Conners. The Trojan Asteroids ; V.Šmēlings. Men on the Moon! ; E.Bervalds. Astronomical Domes and “Sauna” ; Z.Alksne, A.Alksnis. Sakurai’s Object Fails to Escape Own Dust ; Z.Alksne, A.Alksnis. R CrB Stars Surrounded by Dust Clouds ; M.Gills. April Started with Astronomy ; A.Alksnis. First Stamps Dedicated to Astronomy by Latvia’s Post-Office ; I.Pundure. Arturs Balklavs and Astronomy of Latvia (till 1969) ; M.Sudārs. Satellite Collisions – What Threat Do They Pose? ; I.Vilks. Dwarf Planets Names in Latvian ; Announcement on the 2nd International Symposium on Dark-sky Parks: 14-19 September 2009, Slovenia ; A.Andžāns. The Best Way to Fight Darkness Is to Switch on Light (Intervi…

Zemes mākslīgo pavadoņu sadursmesPundurplanētu latviskie nosaukumiAstronomija - jaunākās publikācijasSakuraja zvaigzneKrustvārdu mīkla„Zvaigžņotās Debess” 50 gadiČ.B.Stīvensons (Charles Bruce Stephenson 9.02.1929.-3.12.2001.)Rīgas Politehnikuma ēka - vēstureDr.habil.math. Andris BuiķisVistālākais Visuma objekts GRB 090423R CrB zvaigznesAstronomija filatēlijāLinārs Laucenieks – 75Marsa atmosfēra – metānsGamma staru zvaigzne SGR J1550-5418Dainis Draviņš – 60Starptautiskais Astronomijas gads 2009Jānis Bikše – 70Antonijs Salītis – 60Latvijas matemātikas olimpiādeJānis Klētnieks – 80Leonids Roze (20.05.1925.-1.06.2009.)Cilvēki uz MēnessLatvija astronomija - vēstureAstronomiskās parādības - 2009Visuma tēma filatēlijā – bezpilota kosmiskie lidojumiKosmiskā difūzā plazma – spektroskopijaStarptautiskais simpozijs par Tumšās debess parkiem (Dark-sky Parks)Stiklaplasta kupoliArturs Balklavs-Grīnhofs
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Zvaigžņotā Debess: 2012/13, Ziema (218)

2012

Saturs: Dienas kārtībā – «melnie caurumi» ; «Pioneer-10» dodas uz Jupiteru ; A.Alksnis. Dīvains miglājs, kam daudz nosaukumu ; M.Ņečajeva, I.Šmelds. Jonosfēras pētījumi Ventspils Starptautiskajā radioastronomijas centrā ; L.Gulbe. Satelīts ne tikai televīzijai, bet arī mežu uzraudzībai ; I.Ķešāns. Nīls Ārmstrongs ; Pirmo reizi “ZvD”: Ints Ķešāns ; E.Bervalds. Par Jāņa Ikaunieka iecerēm un VSRC (nobeigums) ; J.Dambītis, A.Cibulis. Ievērojamais Latvijas matemātiķis Arvīds Lūsis (1900–1969) ; A.Alksnis. LVU astronomijas specialitātes studenti – 1952. gada diplomandi (3.turpin.) ; I.D., I.P. Šoziem atceramies: Arturs Balklavs-Grīnhofs (2.I 1933.) – 80, Ernests Grasbergs (8.III 1938.) – 75 ; K.Š…

Zīmuļa miglājs NGC 2736 – Raganas slotaLatvijas 37.atklātā fizikas olimpiāde – uzdevumi un atrisinājumiNīls Ārmstrongs (1930-2012)Matemātiķis Arvīds Lūsis (1900-1969)Zvaigžņu tēma mākslā – dzeja un zīmējumiJānis IkaunieksTehniskās jaunrades nams “Annas 2” – astronomija:NATURAL SCIENCES::Physics::Astronomy and astrophysics [Research Subject Categories]māksla-skaitļi-astronomija [Homo sapiens]Saules halo (Zilais kalns)Edmunds Tukišs (1943-2012)Jonosfēras pētījumi - Ventspils Starptautiskajā radioastronomijas centrsLU Astronomijas institūts – bibliotēkaErnestam Grasbergam – 75Satelīts mežu uzraudzībaiLatvijas 40.atklātā skolēnu astronomijas olimpiāde – uzdevumi un atrisinājumiArturam Balklavam-Grīnhofam – 80Marss – Geila krāteris„ZvD” LU e-resursu repozitārijāLVU astronomijas studenti – 1952.gada diplomandiAstronomiskās parādības – 2012/13.gada ziemā
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A Mobile Computing Framework for Pervasive Adaptive Platforms

2012

International audience; Ubiquitous computing is now the new computing trend, such systems that interact with their environment require self-adaptability. Bioinspiration is a natural candidate to provide the capability to handle complex and changing scenarios. This paper presents a programming framework dedicated to pervasive platforms programming. This bioinspired and agentoriented framework has been developed within the frame of the PERPLEXUS European project that is intended to provide support for bioinspiration-driven system adaptability. This framework enables the platform to adapt itself to application requirements at high-level while using hardware acceleration at node level. The resu…

[INFO.INFO-AR]Computer Science [cs]/Hardware Architecture [cs.AR]Context-aware pervasive systemsUbiquitous computingArticle SubjectComputer Networks and CommunicationsComputer scienceDistributed computingmedia_common.quotation_subjectMobile computing02 engineering and technologycomputer.software_genreAdaptabilitylcsh:QA75.5-76.950202 electrical engineering electronic engineering information engineeringAdaptation (computer science)media_commonbusiness.industryFrame (networking)General Engineering020206 networking & telecommunicationsSoftware frameworkEmbedded systemHardware accelerationRobot020201 artificial intelligence & image processinglcsh:Electronic computers. Computer sciencebusinesscomputer
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Topological properties of cellular automata on trees

2012

We prove that there do not exist positively expansive cellular automata defined on the full k-ary tree shift (for k>=2). Moreover, we investigate some topological properties of these automata and their relationships, namely permutivity, surjectivity, preinjectivity, right-closingness and openness.

[INFO.INFO-CC]Computer Science [cs]/Computational Complexity [cs.CC]FOS: Computer and information sciencesDiscrete Mathematics (cs.DM)Formal Languages and Automata Theory (cs.FL)FOS: Physical sciencesComputer Science - Formal Languages and Automata Theory0102 computer and information sciences[INFO.INFO-DM]Computer Science [cs]/Discrete Mathematics [cs.DM]Computational Complexity (cs.CC)Topology01 natural scienceslcsh:QA75.5-76.95[INFO.INFO-FL]Computer Science [cs]/Formal Languages and Automata Theory [cs.FL]0101 mathematicsF.1.1;F.1.2;F.1.3MathematicsCellular Automata and Lattice Gases (nlin.CG)lcsh:Mathematics010102 general mathematicsCellular automaton tree shift expansivity permutivity right-closingness opennesslcsh:QA1-939Nonlinear Sciences::Cellular Automata and Lattice GasesCellular automatonAutomatonComputer Science - Computational Complexity010201 computation theory & mathematicsTree (set theory)lcsh:Electronic computers. Computer scienceF.1.2F.1.3ExpansiveNonlinear Sciences - Cellular Automata and Lattice GasesF.1.1Computer Science::Formal Languages and Automata TheoryComputer Science - Discrete Mathematics
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Gray code for Cayley permutations

2003

A length-n Cayley permutation p of a total ordered set S is a length-n sequence of elements from S, subject to the condition that if an element x appears in p then all elements y < x also appear in p . In this paper, we give a Gray code list for the set of length-n Cayley permutations. Two successive permutations in this list differ at most in two positions.

[MATH.MATH-CO] Mathematics [math]/Combinatorics [math.CO][MATH.MATH-CO]Mathematics [math]/Combinatorics [math.CO]PermutationsCombinationslcsh:Electronic computers. Computer scienceWeak-orderlcsh:QA75.5-76.95ComputingMilieux_MISCELLANEOUSGray Code
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ECO-generation for some restricted classes of compositions

2013

International audience; We study several restricted classes of compositions by giving one-to-one maps between them and different classes of restricted binary strings or pattern avoiding permutations. Inspired by the ECO method, new succession rules for these classes are presented. Finally, we obtain generating algorithms in Constant Amortized Time (CAT) for theses classes.

[MATH.MATH-CO] Mathematics [math]/Combinatorics [math.CO]succession ruleComposition of an integerECO method[MATH.MATH-CO]Mathematics [math]/Combinatorics [math.CO]lcsh:Electronic computers. Computer science[ MATH.MATH-CO ] Mathematics [math]/Combinatorics [math.CO]generating treepattern avoiding permutationlcsh:QA75.5-76.95
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An attempt to classification of the quasi rational solutions to the NLS equation

2015

Based on a representation in terms of determinants of order 2N , an attempt to classification of quasi rational solutions to the one dimensional focusing nonlinear Schrödinger equation (NLS) is given and several conjectures about the structure of the solutions are also formulated. These solutions can be written as a product of an exponential depending on t by a quotient of two polynomials of degree N (N + 1) in x and t depending on 2N −2 parameters. It is remarkable to mention that in this representation, when all parameters are equal to 0, we recover the PN breathers.

[MATH.MATH-MP]Mathematics [math]/Mathematical Physics [math-ph][ MATH.MATH-MP ] Mathematics [math]/Mathematical Physics [math-ph][MATH.MATH-MP] Mathematics [math]/Mathematical Physics [math-ph]37K10 33Q55 4710A- 4735Fg 4754Bd
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Prospects for advanced electron cyclotron resonance and electron beam ion source charge breeding methods for EURISOL

2011

International audience; As the most ambitious concept of isotope separation on line (ISOL) facility, EURISOL aims at producing unprecedented intensities of post-accelerated radioactive isotopes. Charge breeding, which transforms the charge state of radioactive beams from 1+ to an n+ charge state prior to postacceleration, is a key technology which has to overcome the following challenges: high charge states for high energies, efficiency, rapidity and purity. On the roadmap to EURISOL, a dedicated R&D is being undertaken to push forward the frontiers of the present state-of-the-art techniques which use either electron cyclotron resonance or electron beam ion sources. We describe here the gui…

[PHYS.PHYS.PHYS-ACC-PH]Physics [physics]/Physics [physics]/Accelerator Physics [physics.acc-ph]Cyclotron resonanceplasmafysiikka01 natural sciences7. Clean energyElectron cyclotron resonanceIonlaw.inventionIsotope separationelectron beamsNuclear physicsEURISOLion sourceslaw0103 physical sciencescyclotron resonance010306 general physicsradioactive ion beamsradioactive beamInstrumentation010302 applied physicsPhysicsta11429.25.Ni 41.75.Fr 07.77.KaionilähteetParticle acceleratorradioaktiiviset suihkutIon sourceCathode rayAtomic physicsydinfysiikkaIon cyclotron resonance
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