7,963 research outputs found
q-Differential equations for q-classical polynomials and q-Jacobi-Stirling numbers
Get PDFWe introduce, characterise and provide a combinatorial interpretation for the so-called q-Jacobi–Stirling numbers.
This study is motivated by their key role in the (reciprocal) expansion of any power of a second order
q-differential operator having the q-classical polynomials as eigenfunctions in terms of other even order operators,
which we explicitly construct in this work. The results here obtained can be viewed as the q-version of
those given by Everitt et al. and by the first author, whilst the combinatorics of this new set of numbers is a
q-version of the Jacobi–Stirling numbers given by Gelineau and the second author
Postać n-tej iteracji operatora q = f d/dx
No full textArtykuł nie zawiera streszczeniaMotivated by applications in linear dynamical systems, the author studies q^n(f), where q is the operator f●(d/dx) and qn is its n-th iteration. q^n(f) is a polynomial F(f(0),f(1),...,f(n)) in the derivatives f(0)=f,...,f(n) of f with integer coefficients. Special attention is paid to determining the coefficients of F. The author presents algorithms for computing the coefficients and also shows that the sum of all coefficients of F equals n!. The paper ends with some remarks on the number of coefficients of F, which is related to the number-theoretic unrestricted partition function
Exploring a Mixed Method Approach: Simulation Games and Q Methodology
No full textIn this paper we explore the possibilities to combine two research methods we regard as being very useful when interacting with stakeholders in complex systems. We discuss a mixed research methods approach, based on the Q methodology and a simulation game. In a game design process, translating the real or reference system into the game design is an intricate process and rather challenging due to the complexity of today’s societal systems. As shown by various studies, different data techniques are proposed in order to translate reality aspects. One of the proposed data gathering techniques in combination with simulation games is Q methodology. Q methodology is a suitable method to retrieve social perspectives of stakeholders on a particular topic. Yet it is still elusive how the results of a Q methodology can be used in a game design process. In this paper, we explore the possibilities how to combine the two methods and how to translate the results of the Q analysis into a game design concept. In the context of a case within the domain of transport and logistics, we discuss how such mixed research methods approach could look like. We conclude with a future outlook on our research.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Policy Analysi
Non local resonances in weak turbulence of gravity-capillary waves
No full textWe report a laboratory investigation of weak turbulence of water surface waves in the gravity-capillary crossover. By using time-space resolved profilometry and a bicoherence analysis, we study the 3-wave resonant interactions that are responsible for energy transfer among waves. We show that the energy transfer occurs through non local coupling between capillary and gravity waves
Event-Based Communication in Distributed Q-Learning
No full textWe present an approach to reduce the communication of information needed on a Distributed Q-Learning system inspired by Event Triggered Control (ETC) techniques. We consider a baseline scenario of a Distributed Q-Learning problem on a Markov Decision Process (MDP). Following an event-based approach, N agents sharing a value function explore the MDP and compute a trajectory-dependent triggering signal which they use distributedly to decide when to communicate information to a central learner in charge of computing updates on the action-value function. These decision functions form an Event Based distributed Q learning system (EBd-Q), and we derive convergence guarantees resulting from the reduction of communication. We then apply the proposed algorithm to a cooperative path planning problem, and show how the agents are able to learn optimal trajectories communicating a fraction of the information. Additionally, we discuss what effects (desired and undesired) these event-based approaches have on the learning processes studied, and how they can be applied to more complex multi-agent systems.Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Team Manuel Mazo J
Modification of Loop 1 Affects the Nucleotide Binding Properties of Myo1c, the Adaptation Motor in the Inner Ear
Get PDFMyo1c is one of eight members of the mammalian myosin I family of actin-associated molecular motors. In stereocilia of the hair cells in the inner ear, Myo1c presumably serves as the adaptation motor, which regulates the opening and closing of transduction channels. Although there is conservation of sequence and structure among all myosins in the N-terminal motor domain, which contains the nucleotide- and actin-binding sites, some differences include the length and composition of surface loops, including loop 1, which lies near the nucleotide-binding domain. To investigate the role of loop 1, we expressed in insect cells mutants of a truncated form of Myo1c, Myo1c1IQ, as well as chimeras of Myo1c1IQ with the analogous loop from other myosins. We found that replacement of the charged residues in loop 1 with alanines or the whole loop with a series of alanines did not alter the ATPase activity, transient kinetics properties, or Ca2+ sensitivity of Myo1c1IQ. Substitution of loop 1 with that of the corresponding region from tonic smooth muscle myosin II (Myo1c1IQ-tonic) or replacement with a single glycine (Myo1c1IQ-G) accelerated the release of ADP from A.M 2?3-fold in Ca2+, whereas substitution with loop 1 from phasic muscle myosin II (Myo1c1IQ-phasic) accelerated the release of ADP 35-fold. Motility assays with chimeras containing a single ?-helix, or SAH, domain showed that Myo1cSAH-tonic translocated actin in vitro twice as fast as Myo1cSAH-WT and 3-fold faster than Myo1cSAH-G. The studies show that changes induced in Myo1c via modification of loop 1 showed no resemblance to the behavior of the loop donor myosins or to the changes previously observed with similar Myo1b chimeras
Metabolic profiling and population screening of analgesic usage in nuclear magnetic resonance spectroscopy-based large-scale epidemiologic studies
Get PDFThe application of a 1H nuclear magnetic resonance (NMR) spectroscopy-based screening method for determining the use of two widely available analgesics (acetaminophen and ibuprofen) in epidemiologic studies has been investigated. We used samples and data from the cross-sectional INTERMAP Study involving participants from Japan (n = 1145), China (n = 839), U.K. (n = 501), and the U.S. (n = 2195). An orthogonal projection to latent structures discriminant analysis (OPLS-DA) algorithm with an incorporated Monte Carlo resampling function was applied to the NMR data set to determine which spectra contained analgesic metabolites. OPLS-DA preprocessing parameters (normalization, bin width, scaling, and input parameters) were assessed systematically to identify an optimal acetaminophen prediction model. Subsets of INTERMAP spectra were examined to verify and validate the presence/absence of acetaminophen/ibuprofen based on known chemical shift and coupling patterns. The optimized and validated acetaminophen model correctly predicted 98.2%, and the ibuprofen model correctly predicted 99.0% of the urine specimens containing these drug metabolites. The acetaminophen and ibuprofen models were subsequently used to predict the presence/absence of these drug metabolites for the remaining INTERMAP specimens. The acetaminophen model identified 415 out of 8436 spectra as containing acetaminophen metabolite signals while the ibuprofen model identified 245 out of 8604 spectra as containing ibuprofen metabolite signals from the global data set after excluding samples used to construct the prediction models. The NMR-based metabolic screening strategy provides a new objective approach for evaluation of self-reported medication data and is extendable to other aspects of population xenometabolome profiling
Optimising floor systems for Q-houses
No full textThe current way of building in The Netherlands has several consequences that have an impact on nature and determine the indoor climate of a house. To improve the way of building and the indoor climate, a cooperative association ‘Q’ was set up to realise this goal. The association ‘Q’ has invented a unique, innovative, and intelligent building system. In these so called Q-houses at least 90% of the materials used are renewable. These materials, such as timber and sheep’s wool, provide a healthy indoor climate. The building system of a Q-house is a core building. This core provides stability. The walls outside the core are only supporting elements, they don’t provide stability. Due to this building system, flexibility is created for the building of different styles of houses. At the moment, 18 Q-houses have been built in The Netherlands. However, the evaluation of the construction has not taken place yet. Evaluating an entire Q-house would take more time than the time set for one graduation period. Because the floor is made of innovative elements that have not been used in earlier projects, this part of a Q-house will be evaluated. The objective of this graduation project is the evaluation and reconsideration of the choices that were made in the design process of the floor, to be able to optimise the floor. The floor is made of pre-stressed laminated elements. The elements span in the longitudinal direction of the house and are pre-stressed in the direction, perpendicular to the grain. The main reason for prestressing is that all elements work together as one piece. Evaluation clearly showed the strengths and weaknesses of the floor. The most important strength is the avoiding of gaps between the elements due to the pre-stressing. The most important weakness is that, due to the pre-stressing method, operations have to be done by hand. This increases the cost price.Design and ConstructionCivil Engineering and Geoscience
Finite dimensional semisimple Q-algebras
Get PDFA Q-algebra can be represented as an operator algebra on an infinite dimensional Hilbert space. However we don’t know whether a finite n-dimensional Q-algebra can be represented on a Hilbert space of dimension n except n = 1, 2. It is known that a two dimensional Q-algebra is just a two dimensional commutative operator algebra on a two dimensional Hilbert space. In this paper we study a finite n-dimensional semisimple Q-algebra on a finite n-dimensional Hilbert space. In particular we describe a three dimensional Q-algebra of the disc algebra on a three dimensional Hilbert space. Our studies are related to the Pick interpolation problem for a uniform algebra
(2,3)-Generation Of SL(n,q). - I. Cases n = 5,6,7.
No full text. In this paper we prove that the groups SL(n; q), q = p m , are factors of the modular group PSL(2; Z) when n = 5; 6; 7 and p 6= 2, q 6= 9. Introduction There is growing evidence that most finite simple groups (and closely related groups) appear as factor-groups of the classical modular group PSL(2; Z). It is well known that PSL(2; Z) is isomorphic to the free product of the groups of orders 2 and 3 and thus a group appears as a factor-group of PSL(2; Z) if and only if it is generated by an involution and an element of order 3. Such groups are often called (2,3)-generated. * The first-named author was supported by the Ministero dell'Universit`a e della Ricerca Scientifica e Tecnologica (M.U.R.S.T.) ** The second-named author gratefully acknowledges the financial support of the Consiglio Nazionale delle Ricerche (C.N.R.) and the hospitality of the Universit`a degli Studi di Milano during the preparation of this work. AMS 1991 Subject Classification: 20G40, 20F05 Keywords: special l..
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