1,362 research outputs found

    Point sets that minimize (k)(\le k)-edges, 3-decomposable drawings, and the rectilinear crossing number of K30K_{30}

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    There are two properties shared by all known crossing-minimizing geometric drawings of KnK_n, for nn a multiple of 3. First, the underlying nn-point set of these drawings has exactly 3(k+22)3\binom{k+2}{2} (k)(\le k)-edges, for all 0k<n/30\le k < n/3. Second, all such drawings have the nn points divided into three groups of equal size; this last property is captured under the concept of 3-decomposability. In this paper we show that these properties are tightly related: every nn-point set with exactly 3(k+22)3\binom{k+2}{2} (k)(\le k)-edges for all 0k<n/30\le k < n/3, is 3-decomposable. As an application, we prove that the rectilinear crossing number of K30K_{30} is 9726.Comment: 14 page

    Enabling SmartWorkflows over heterogeneous ID-sensing technologies

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    Sensing technologies in mobile devices play a key role in reducing the gapbetween the physical and the digital world. The use of automatic identification capabilitiescan improve user participation in business processes where physical elements are involved(Smart Workflows). However, identifying all objects in the user surroundings does notautomatically translate into meaningful services to the user. This work introduces Parkour,an architecture that allows the development of services that match the goals of each ofthe participants in a smart workflow. Parkour is based on a pluggable architecture thatcan be extended to provide support for new tasks and technologies. In order to facilitatethe development of these plug-ins, tools that automate the development process are alsoprovided. Several Parkour-based systems have been developed in order to validate theapplicability of the proposal

    Sympathetic and swap cooling of trapped ions by cold atoms in a MOT

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    A mixed system of cooled and trapped, ions and atoms, paves the way for ion assisted cold chemistry and novel many body studies. Due to the different individual trapping mechanisms, trapped atoms are significantly colder than trapped ions, therefore in the combined system, the strong binary ion-atom interaction results in heat flow from ions to atoms. Conversely, trapped ions can also get collisionally heated by the cold atoms, making the resulting equilibrium between ions and atoms intriguing. Here we experimentally demonstrate, Rubidium ions (Rb+^+) cool in contact with magneto-optically trapped (MOT) Rb atoms, contrary to the general expectation of ion heating for equal ion and atom masses. The cooling mechanism is explained theoretically and substantiated with numerical simulations. The importance of resonant charge exchange (RCx) collisions, which allows swap cooling of ions with atoms, wherein a single glancing collision event brings a fast ion to rest, is discussed.Comment: 10 pages, 3 figure

    Evaluation of the total photoabsorption cross sections for actinides from photofission data and model calculations

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    We have calculated the fission probabilities for 237-Np, 233,235,238-U, 232-Th, and nat-Pb following the absorption of photons with energies from 68 MeV to 3.77 GeV using the RELDIS Monte-Carlo code. This code implements the cascade-evaporation-fission model of intermediate-energy photonuclear reactions. It includes multiparticle production in photoreactions on intranuclear nucleons, pre-equilibrium emission, and the statistical decay of excited residual nuclei via competition of evaporation, fission, and multifragmentation processes. The calculations show that in the GeV energy region the fission process is not solely responsible for the entire total photoabsorption cross section, even for the actinides: ~55-70% for 232-Th, \~70-80% for 238-U, and ~80-95% for 233-U, 235-U, and 237-Np. This is because certain residual nuclei that are created by deep photospallation at GeV photon energies have relatively low fission probabilities. Using the recent experimental data on photofission cross sections for 237-Np and 233,235,238-U from the Saskatchewan and Jefferson Laboratories and our calculated fission probabilities, we infer the total photoabsorption cross sections for these four nuclei. The resulting cross sections per nucleon agree in shape and in magnitude with each other. However, disagreement in magnitude with total-photoabsorption cross-section data from previous measurements for nuclei from C to Pb calls into question the concept of a ``Universal Curve'' for the photoabsorption cross section per nucleon for all nuclei.Comment: 39 pages including 11 figure

    Combined ion and atom trap for low temperature ion-atom physics

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    We report an experimental apparatus and technique which simultaneously traps ions and cold atoms with spatial overlap. Such an apparatus is motivated by the study of ion-atom processes at temperatures ranging from hot to ultra-cold. This area is a largely unexplored domain of physics with cold trapped atoms. In this article we discuss the general design considerations for combining these two traps and present our experimental setup. The ion trap and atom traps are characterized independently of each other. The simultaneous operation of both is then described and experimental signatures of the effect of the ions and cold-atoms on each other are presented. In conclusion the use of such an instrument for several problems in physics and chemistry is briefly discussed.Comment: 24 pages, 13 figures. Figures Fixe

    Using Magentix2 in Smart-Home Environments

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    [EN] In this paper, we present the application of a multi-agent platform Magentix2 for the development of MAS in smart-homes. Specificallly, the use of Magentix2 (http://gti-ia.upv.es/sma/tools/magentix2/index.php) platform facilitates the management of the multiple occupancy in smart living spaces. Virtual organizations provide the possibility of defining a set of norms and roles that facilitate the regulation and control of the actions that can be carried out by the internal and external agents depending on their profile. We illustrate the applicability of our proposal with a set of scenarios. © Springer International Publishing Switzerland 2015.This work is supported by the Spanish government grants CONSOLIDER INGENIO 2010 CSD2007-00022, MINECO/FEDER TIN2012-36586-C03-01, TIN2011-27652-C03-01, and SP2014800.Valero Cubas, S.; Del Val Noguera, E.; Alemany Bordera, J.; Botti, V. (2015). Using Magentix2 in Smart-Home Environments. En 10th International Conference on Soft Computing Models in Industrial and Environmental Applications. Springer Verlag. 27-37. https://doi.org/10.1007/978-3-319-19719-7_3S2737Bajo J, Fraile JA, Pérez-Lancho B, Corchado JM (2010) The thomas architecture in home care scenarios: a case study. Expert Syst Appl 37(5):3986–3999Cetina C, Giner P, Fons J, Pelechano V (2009) Autonomic computing through reuse of variability models at runtime: The case of smart homes. Computer 42(10):37–43Cook DJ (2009) Multi-agent smart environments. J Ambient Intell Smart Environ 1(1):51–55Crandall AS, Cook DJ (2010) Using a hidden markov model for resident identification. In: 6th international conference on intelligent environments, pp 74–79. IEEECriado N, Argente E, Botti V (2013) THOMAS: an agent platform for supporting normative multi-agent systems. J Logic Comput 23(2):309–333Davidoff S, Lee MK, Zimmerman J, Dey A (2006) Socially-aware requirements for a smart home. In: Proceedings of the international symposium on intelligent, environments, pp 41–44Grupo de Tecnología Informática e Inteligencia Artificial (GTI-IA) (2015). http://www.gti-ia.upv.es/sma/tools/magentix2/archivos/Magentix2UserManualv2.1.0.pdf . Magentix2 User’s Manual v2.0Loseto G, Scioscia F, Ruta M, di Sciascio E (2012) Semantic-based smart homes: a multi-agent approach. In: 13th Workshop on objects and agents (WOA 2012), vol 892, pp 49–55Rodriguez S, Julián V, Bajo J, Carrascosa C, Botti V, Corchado JM (2011) Agent-based virtual organization architecture. Eng Appl Artif Intell 24(5):895–910Rodríguez S, Paz JFD, Villarrubia G, Zato C, Bajo J, Corchado JM (2015) Multi-agent information fusion system to manage data from a WSN in a residential home. Inf Fusion 23:43–57Such JM, Garca-Fornes A, Espinosa A, Bellver J (2012) Magentix2: a Privacy-enhancing Agent Platform. Eng Appl Artif IntellSun Q, Yu W, Kochurov N, Hao Q, Hu F (2013) A multi-agent-based intelligent sensor and actuator network design for smart house and home automation. J Sens Actuator Netw 2(3):557–588Val E, Criado N, Rebollo M, Argente E, Julian V (2009) Service-oriented framework for virtual organizations. 1:108–114Wu C-L, Liao C-F, Fu L-C (2007) Service-oriented smart-home architecture based on osgi and mobile-agent technology. IEEE Trans Syst Man Cybern Part C Appl Rev 37(2):193–205Yin J, Yang Q, Shen D, Li Z-N (2008) Activity recognition via user-trace segmentation. ACM Trans Sens Netw (TOSN) 4(4):1

    Corporal diagnostic work and diagnostic spaces: Clinicians' use of space and bodies during diagnosis

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    © 2015 The Authors. Sociology of Health & Illness © 2015 Foundation for the Sociology of Health & Illness/John Wiley & Sons Ltd. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.An emerging body of literature in sociology has demonstrated that diagnosis is a useful focal point for understanding the social dimensions of health and illness. This article contributes to this work by drawing attention to the relationship between diagnostic spaces and the way in which clinicians use their own bodies during the diagnostic process. As a case study, we draw upon fieldwork conducted with a multidisciplinary clinical team providing deep brain stimulation (DBS) to treat children with a movement disorder called dystonia. Interviews were conducted with team members and diagnostic examinations were observed. We illustrate that clinicians use communicative body work and verbal communication to transform a material terrain into diagnostic space, and we illustrate how this diagnostic space configures forms of embodied 'sensing-and-acting' within. We argue that a 'diagnosis' can be conceptualised as emerging from an interaction in which space, the clinician-body, and the patient-body (or body-part) mutually configure one another. By conceptualising diagnosis in this way, this article draws attention to the corporal bases of diagnostic power and counters Cartesian-like accounts of clinical work in which the patient-body is objectified by a disembodied medical discourse.The Wellcome Trust (Wellcome Trust Biomedical Strategic Award 086034

    Decay of spin coherences in one-dimensional spin systems

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    Strategies to protect multi-qubit states against decoherence are difficult to formulate because of their complex many-body dynamics. A better knowledge of the decay dynamics would help in the construction of dynamical decoupling control schemes. Here we use solid-state nuclear magnetic resonance techniques to experimentally investigate decay of coherent multi-spin states in linear spin chains. Leveraging on the quasi-one-dimension geometry of fluorapatite crystal spin systems, we can gain a deeper insight on the multi-spin states created by the coherent evolution, and their subsequent decay, than it is possible in three-dimensional (3D) systems. We are then able to formulate an analytical model that captures the key features of the decay. We can thus compare the decoherence behavior for different initial states of the spin chain and link their decay rate to the state characteristics, in particular their coherence and long-range correlation among spins. Our experimental and theoretical study shows that the spin chains undergo a rich dynamics, with a slower decay rate than for the 3D case, and thus might be more amenable to decoupling techniques.National Science Foundation (U.S.) (Grant DMG-1005926)United States. Air Force Office of Scientific Research. Young Investigator Progra

    Scraping the Social? Issues in live social research

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    What makes scraping methodologically interesting for social and cultural research? This paper seeks to contribute to debates about digital social research by exploring how a ‘medium-specific’ technique for online data capture may be rendered analytically productive for social research. As a device that is currently being imported into social research, scraping has the capacity to re-structure social research, and this in at least two ways. Firstly, as a technique that is not native to social research, scraping risks to introduce ‘alien’ methodological assumptions into social research (such as an pre-occupation with freshness). Secondly, to scrape is to risk importing into our inquiry categories that are prevalent in the social practices enabled by the media: scraping makes available already formatted data for social research. Scraped data, and online social data more generally, tend to come with ‘external’ analytics already built-in. This circumstance is often approached as a ‘problem’ with online data capture, but we propose it may be turned into virtue, insofar as data formats that have currency in the areas under scrutiny may serve as a source of social data themselves. Scraping, we propose, makes it possible to render traffic between the object and process of social research analytically productive. It enables a form of ‘real-time’ social research, in which the formats and life cycles of online data may lend structure to the analytic objects and findings of social research. By way of a conclusion, we demonstrate this point in an exercise of online issue profiling, and more particularly, by relying on Twitter to profile the issue of ‘austerity’. Here we distinguish between two forms of real-time research, those dedicated to monitoring live content (which terms are current?) and those concerned with analysing the liveliness of issues (which topics are happening?)
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