127 research outputs found

    Water induced sediment levitation enhances downslope transport on Mars

    Get PDF
    On Mars, locally warm surface temperatures (~293 K) occur, leading to the possibility of (transient) liquid water on the surface. However, water exposed to the martian atmosphere will boil, and the sediment transport capacity of such unstable water is not well understood. Here, we present laboratory studies of a newly recognized transport mechanism: “levitation” of saturated sediment bodies on a cushion of vapor released by boiling. Sediment transport where this mechanism is active is about nine times greater than without this effect, reducing the amount of water required to transport comparable sediment volumes by nearly an order of magnitude. Our calculations show that the effect of levitation could persist up to ~48 times longer under reduced martian gravity. Sediment levitation must therefore be considered when evaluating the formation of recent and present-day martian mass wasting features, as much less water may be required to form such features than previously thought

    What are the competences in information system required by managers? Curriculum development for management and public administration degrees

    Get PDF
    [EN] This paper analyzes the competences required by executives to manage information system, and consequently, the competences that must define the information system subjects in non-technical degrees, degrees, such as Public Administration or Business Management. This work reviews the literature about business managers competences on Information Technologies (IT) and compares the theory with the traditional body of knowledge about information systems taught at business schools. By analyzing the executives function, their role in the information system management, and, above, all the importance of their decisions in the effective integration of IT in business processes, this work proposes specific development in seven knowledge areas that facilitate the acquisition of these types of executive competencesDevece Carañana, CA.; Peris-Ortiz, M.; Rueda Armengot, C. (2016). What are the competences in information system required by managers? Curriculum development for management and public administration degrees. Technology, Innovation and Education. 2(10):1-9. doi:10.1186/s40660-016-0016-2S19210Bassellier G, Benbasat I (2004) Business competence of IT professionals: conceptual development and influence on IT-business partnerships. MIS Q 28(4):673–694Bassellier G, Reich BH, Benbasat I (2001) Information technology competence of business managers: a definition and research model. J Manag Inf Syst 17(4):159–182Bassellier G, Benbasat I, Reich BH (2003) The influence of business managers’ IT competence on championing IT. Inf Syst Res 14(4):317–336Bettiol M, Di Maria E, Finotto V (2012) Marketing in SMEs: the role of entrepreneurial sensemaking. Int Entrep Manag J 8(2):223–248Boyatzis RE (1982) The competent manager a model for effective performance. Wiley, New YorkBoynton AC, Zmud RW, Jacobs GC (1994) The influence of IT management practice on IT use in large organizations. MIS Q 18(3):299–318Broadbent M, Weill P (1993) Improving business and information strategy alignment: learning from the banking industry. IBM Syst J 32(1):162–179Brown CV, Magill SL (1994) Alignment of the IS functions with the enterprise: toward a model of antecedents. MIS Q 18(4):371–403Busch EA, Jarvenpaa SL, Tractinsky N, Glick WH (1991) External versus internal perspectives in determining a firm’s progressive use of information technology. Proceedings of the 12th International Conference on Information Systems, New York, 1991:239–250Camisón C (2002) On the relevance of industry, competitive scope, strategic group, size and distinctive competences construct on explaining of organizational performance. Universitat jaume I, Castellón (Working Paper 1–02,Research Group on Strategy, Knowledge Management and Organizational Learning)Castanias RP, Helfat CE (1991) Managerial resources and rents. J Manag 17:155–171Cegarra-Navarro JG, Sánchez-Vidal ME, Cegarra-Leiva D (2011) Balancing exploration and exploitation of knowledge through an unlearning context: an empirical investigation in SMEs. Manag Decis 49(7):1099–1119Chan YE, Reich BH (2007) IT alignment: what have we learned? J Inf Tech 22:297–315Chan YE, Sabherwal R, Thatcher JB (2006) Antecedents and outcomes of strategic IS alignment: an empirical investigation. IEEE Trans Eng Manag 51(3):27–47Croteau AM, Bergeron F (2001) An information technology trilogy: business strategy, technological deployment and organizational performance. J Strateg Inf Syst 10:77–99Crowston K, Myers MD (2004) Information technology and the transformation of industries: three research perspectives. J Strateg Inf Syst 13(1):5–28Dent-Micallef A, Powell T (1998) Technologies de l’information: nécessités stratégiques ou sources d’avantage concurrentiel? Une étude empirique dans le secteur de la distribution aux Etats-Unis. Rev Can Sci Adm 15(1):39–64Devece C (2013) The value of business managers’ ‘information technology’ competence. Serv Ind J 33(7/8):720–733Doll WJ, Torkzadeh G (1987) The relationship of MIS steering committee to size of firm and formalization of mis planning. Commun ACM 30(11):972–978Earl MJ (1996) The risks of outsourcing IT. Sloan Manag Rev 37(3):26–32European Commission (2015) ECTS Users’ Guide 2015. Publications Office of the European Union, Luxembourg. doi: 10.2766/87592Hambrick DC, Brandon G (1988) Executive values. In: Hambrick DC (ed) The executive effect: concepts and methods for studying top managers. JAI Press, GreenwichHambrick DC, Mason PA (1984) Upper echelons: the organization as a reflection of its top managers. Acad Manag Rev 9(2):193–206Hotho S, Champion K (2011) Small businesses in the new creative industries: innovation as a people management challenge. Manag Decis 49(1):29–54Jarvenpaa SL, Ives B (1991) Executive involment and participation in the management of IT. MIS Q 15(2):52–69Lado AA, Wilson MC (1994) Human resource systems and sustained competitive advantage: a competency-based perspective. Acad Manag Rev 19(4):699–727Lado AA, Boyd NG, Wright P (1992) A competency-based model of sustainable competitive advantage: toward a conceptual integration. J Manag 18(1):77–91Lederer AL, Mendelow AL (1988) Information systems planning: top management takes control. Bus Horiz 31(3):73–78Oh W, Pinsonneault A (2007) On the assessment of the strategic value of information technologies: conceptual and analytical approaches. MIS Q 31(2):239–265Osbaldeston M, Barham K (1992) Using management development for competitive advantage. Long Range Plan 25(6):18–24Penrose ET (1959) The theory of the growth of the firm. Basil Blackwell, OxfordReich BH, Benbasat I (1996) Measuring the linkage between business and information technology objectives. MIS Q 20(1):55–81Reich BH, Benbasat I (2000) Factors that influence the social dimension of alignment between business and information techonology objectives. MIS Q 24(1):81–113Riegner C (2007) Word of mouth on the web: the impact of web 2.0 on consumer purchase decisions. J Advert Res 47(4):436–447Rockart JF (1988) The lines takes the leadership. Sloan Manag Rev 29(4):57–64Sabherwal R, Chan YE (2001) Alignment between business and IS strategies: a study of prospectors, analyzers, and defenders. Inf Syst Res 12(1):11–33Sanchez R, Heene A, Thomas H (1996) Towards the theory and practice of competence-based competition. In: Sanchez R, Heene A, Thomas H (eds) Dynamics of competence-based competition: theory and practice in the new strategic management. Elsevier, London, pp 1–35Senge PM (1990) The fifth discipline: the age and practice of the learning organization. Century Business, LondonSiegel DS, Renko M (2012) The role of market and technological knowledge in recognizing entrepreneurial opportunities. Manag Decis 50(5):797–816Stare M, Jaklic A, Kotnik P (2006) Exploiting ICT potential in service firms in transition economies. Serv Ind J 26(3):287–302Swanson EB (1974) Management information systems: appreciation and involvement. Manag Sci 21(2):178–188Torkzadeh G, Xia W (1992) Managing telecommunications by steering committee. MIS Q 16(2):187–199Westley F, Mintzberg H (1989) Visionary leadership and strategic management. Strateg Manag J 10:17–32Yang TT, Li CR (2011) Competence exploration and exploitation in new product development: the moderating effects of environmental dynamism and competitiveness. Manag Decis 49(9):1444–147

    Search for Gravitational Wave Bursts from Six Magnetars

    Get PDF
    Soft gamma repeaters (SGRs) and anomalous X-ray pulsars (AXPs) are thought to be magnetars: neutron stars powered by extreme magnetic fields. These rare objects are characterized by repeated and sometimes spectacular gamma-ray bursts. The burst mechanism might involve crustal fractures and excitation of non-radial modes which would emit gravitational waves (GWs). We present the results of a search for GW bursts from six galactic magnetars that is sensitive to neutron star f-modes, thought to be the most efficient GW emitting oscillatory modes in compact stars. One of them, SGR 0501+4516, is likely similar to 1 kpc from Earth, an order of magnitude closer than magnetars targeted in previous GW searches. A second, AXP 1E 1547.0-5408, gave a burst with an estimated isotropic energy >10(44) erg which is comparable to the giant flares. We find no evidence of GWs associated with a sample of 1279 electromagnetic triggers from six magnetars occurring between 2006 November and 2009 June, in GW data from the LIGO, Virgo, and GEO600 detectors. Our lowest model-dependent GW emission energy upper limits for band-and time-limited white noise bursts in the detector sensitive band, and for f-mode ringdowns (at 1090 Hz), are 3.0 x 10(44)d(1)(2) erg and 1.4 x 10(47)d(1)(2) erg, respectively, where d(1) = d(0501)/1 kpc and d(0501) is the distance to SGR 0501+4516. These limits on GW emission from f-modes are an order of magnitude lower than any previous, and approach the range of electromagnetic energies seen in SGR giant flares for the first time.United States National Science FoundationScience and Technology Facilities Council of the United KingdomMax-Planck-SocietyState of Niedersachsen/GermanyItalian Istituto Nazionale di Fisica NucleareFrench Centre National de la Recherche ScientifiqueAustralian Research CouncilCouncil of Scientific and Industrial Research of IndiaIstituto Nazionale di Fisica Nucleare of ItalySpanish Ministerio de Educacion y CienciaConselleria d'Economia Hisenda i Innovacio of the Govern de les Illes BalearsFoundation for Fundamental Research on Matter supported by the Netherlands Organisation for Scientific ResearchPolish Ministry of Science and Higher EducationFoundation for Polish ScienceRoyal SocietyScottish Funding CouncilScottish Universities Physics AllianceNational Aeronautics and Space Administration NNH07ZDA001-GLASTCarnegie TrustLeverhulme TrustDavid and Lucile Packard FoundationResearch CorporationAlfred P. Sloan FoundationRussian Space AgencyRFBR 09-02-00166aIPN JPL Y503559 (Odyssey), NASA NNG06GH00G, NASA NNX07AM42G, NASA NNX08AC89G (INTEGRAL), NASA NNG06GI896, NASA NNX07AJ65G, NASA NNX08AN23G (Swift), NASA NNX07AR71G (MESSENGER), NASA NNX06AI36G, NASA NNX08AB84G, NASA NNX08AZ85G (Suzaku), NASA NNX09AU03G (Fermi)Astronom

    NICE : A Computational solution to close the gap from colour perception to colour categorization

    Get PDF
    The segmentation of visible electromagnetic radiation into chromatic categories by the human visual system has been extensively studied from a perceptual point of view, resulting in several colour appearance models. However, there is currently a void when it comes to relate these results to the physiological mechanisms that are known to shape the pre-cortical and cortical visual pathway. This work intends to begin to fill this void by proposing a new physiologically plausible model of colour categorization based on Neural Isoresponsive Colour Ellipsoids (NICE) in the cone-contrast space defined by the main directions of the visual signals entering the visual cortex. The model was adjusted to fit psychophysical measures that concentrate on the categorical boundaries and are consistent with the ellipsoidal isoresponse surfaces of visual cortical neurons. By revealing the shape of such categorical colour regions, our measures allow for a more precise and parsimonious description, connecting well-known early visual processing mechanisms to the less understood phenomenon of colour categorization. To test the feasibility of our method we applied it to exemplary images and a popular ground-truth chart obtaining labelling results that are better than those of current state-of-the-art algorithms

    Draft genome sequence and genetic transformation of the oleaginous alga Nannochloropis gaditana

    Get PDF
    The potential use of algae in biofuels applications is receiving significant attention. However, none of the current algal model species are competitive production strains. Here we present a draft genome sequence and a genetic transformation method for the marine microalga Nannochloropsis gaditana CCMP526. We show that N. gaditana has highly favourable lipid yields, and is a promising production organism. The genome assembly includes nuclear (~29 Mb) and organellar genomes, and contains 9,052 gene models. We define the genes required for glycerolipid biogenesis and detail the differential regulation of genes during nitrogen-limited lipid biosynthesis. Phylogenomic analysis identifies genetic attributes of this organism, including unique stramenopile photosynthesis genes and gene expansions that may explain the distinguishing photoautotrophic phenotypes observed. The availability of a genome sequence and transformation methods will facilitate investigations into N. gaditana lipid biosynthesis and permit genetic engineering strategies to further improve this naturally productive alga

    A Practitioner’s Guide to Performing a Holistic Evaluation of Technology-Enhanced Learning in Medical Education

    No full text
    Technology-enhanced learning (TEL) is now a common mode of educational delivery within medical education. Despite this upsurge, there remains a paucity in comprehensive evaluation of TEL efficacy. In order to make meaningful and evidence-informed decisions on ‘how’ and ‘when’ to utilise technology within a course, ‘useful knowledge’ is required to support faculty in these decision-making processes. In this monograph, a series of pragmatic and achievable approaches for conducting a holistic evaluation of a TEL resource intervention are detailed. These suggestions are based on an established TEL evaluation framework, as well as the author’s own experience and that of the broader literature. The approaches cover development of an appropriate research question that is based on the availability of existing TEL resources alongside the peer-reviewed literature; the development of an appropriate team as well as recommendations for navigating ethical approval; conducting small-scale quantitative and qualitative measure; and performing a large-scale mixed methods assessment to understand the holistic impact of the TEL resource
    corecore