4,614 research outputs found

    Strategies for estimating the marine geoid from altimeter data

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    Altimeter data from a spacecraft borne altimeter was processed to estimate the fine structure of the marine geoid. Simulation studies show that, among several competing parameterizations, the mean free air gravity anomaly model exhibited promising geoid recovery characteristics. Using covariance analysis techniques, quantitative measures of the orthogonality properties are investigated

    Strategies for estimating the marine geoid from altimeter data

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    In processing altimeter data from a spacecraft borne altimeter to estimate the fine structure of the marine geoid, a problem is encountered. In order to describe the geoid fine structure, a large number of parameters must be employed and it is not possible to simultaneously estimate all of them. Unless the parameterization exhibits good orthogonality in the data, serious aliasing results. From simulation studies it has been found that amongst several competing parameterizations, the mean free air gravity anomaly model (i.e., Stokes' formula) exhibited promising geoid recovery characteristics. Using covariance analysis techniques, this report provides quantitative measures of the orthogonality properties associated with the above mentioned parameterization. It has been determined that a 5 deg x 5 deg area mean free air gravity anomaly can be estimated with an uncertainty of 1 mgal (40 cm undulation) provided that all free air gravity anomalies within a spherical radius of 10 arc degrees are simultaneously estimated

    Weak boson production measured in PbPb and pp collisions by CMS

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    The unprecedented center-of-mass energy available at the LHC offers unique opportunities for studying the properties of the strongly-interacting QCD matter created in PbPb collisions at extreme temperatures and very low parton momentum fractions. Electroweak boson production is an important benchmark process at hadron colliders. Precise measurements of Z production in heavy-ion collisions can help to constrain nuclear PDFs as well as serve as a standard candle of the initial state in PbPb collisions at the LHC energies. The inclusive and differential measurements of the Z boson yield in the muon decay channel will be presented, establishing that no modification is observed with respect to next-to-leading order pQCD calculations, scaled by the number of incoherent nucleon-nucleon collisions. The status of the Z measurement in the electron decay channel, as well as the first observation of W \rightarrow \mu {\nu} in heavy ion collisions will be given. The heavy-ion results will be presented in the context of those obtained in pp collisions with the CMS detector.Comment: Quark Matter 2011 conference proceeding

    Promote interculturalism, leadership communication, and professionalism in your students: Success with a corporate communication certificate

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    Business educators share a common interest in encouraging their students to improve intercultural, leadership communication, and professionalism skills to enable and promote increased fulfilment, character development, and advancement toward graduation, in addition to improving student employability after graduation. While career success depends on the standards and knowledge of character and behavioral traits, much more than on technical knowledge, these attributes define the qualities desired across various professions (Barnhart, 2013) in these three areas. For example, Holmes (2015) found that the values and communication rules of discourse systems may be different from that which is expected in the international workplace.A Certificate in Corporate Communication promotes the skillsets for interculturalism, leadership communication, and professionalism. With the positive feedback already received from several entities, including business executives; the student success of relevant development of skillsets for any business or non-business major; and the opportunity to showcase the communication courses to all students and programs at the University, the Certificate of Corporate Communication has already proven its success

    Quantum state of the multiverse

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    A third quantization formalism is applied to a simplified multiverse scenario. A well defined quantum state of the multiverse is obtained which agrees with standard boundary condition proposals. These states are found to be squeezed, and related to accelerating universes: they share similar properties to those obtained previously by Grishchuk and Siderov. We also comment on related works that have criticized the third quantization approach.Comment: 15 pages, 2 figure

    Separador de fragmentos (F.R.S.) como herramienta para el análisis de reacciones nucleares a FAIR (FAcility for Antiproton and Ion Research in Europe)

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    Cada día la ciencia ha tenido que recurrir a la construcción de grandes instalaciones e instrumentos para realizar experimentos que permitan obtener información para que posteriormente sea analizada. En la física nuclear la creación de nuevas instalaciones ha venido creciendo a enormes pasos ya que para estudiar esta área de la física ha sido necesario construir aceleradores, espectrómetros magnéticos y detectores con el objetivo de obtener información experimental de sucesos a escala microscópica. En el presente artículo se hace una revisión acerca del proceso del diseño y construcción del espectrómetro de alta resolución magnética SUPER-FRS (Super-Fragment Separator) es resultado de una gran colaboración llamada FAIR en (Darmstadt) Alemania en las instalaciones del GSI con el fin de conocer la motivación científica que llevó a construirlo, su diseño técnico y trabajos que se han de realizar en él.Everyday science has had to resort to the construction of large facilities and instruments to carry out experiments that allow obtaining information so that it can be analyzed later. In nuclear physics, the creation of new facilities has been growing enormously since to study this area of physics it has been necessary to build accelerators, magnetic spectrometers and detectors in order to obtain experimental information of events on a microscopic scale. This article reviews the design and construction process of the SUPER-FRS (Super-Fragment Separator) magnetic high resolution spectrometer resulting from a great collaboration called FAIR in (Darmstadt) Germany in the GSI facilities with the In order to know the scientific motivation that led to build it, its technical design and work that has been done on it

    NONLINEAR MODELS WITH REPEATED MEASURES FOR ANALYZING DISEASE PROGRESS IN PLANT EPIDEMIOLOGY

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    Nonlinear models are commonly used in plant disease epidemiology to model temporal changes in the proportion of diseased plants (disease index). Most of the times they are fit using linearizing transformations or nonlinear least squares. These approaches assume that the disease index has a normal distribution, that they are independent and that they have constant variance. None of these assumptions can be justified in disease indices. In this paper we apply different strategies to model the progress of papaya ring spot virus in papaya. Using the logistic model we compare different strategies using the SAS® System. Marginal (population average) and subjectspecific interpretations of the models are discussed

    Stability and magnetic properties of T2Sin (T=Cr,Mn,1≤n≤8) clusters

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    First-principles studies on the geometry, electronic structure, and magnetic properties of neutral and anionic Cr2Sin and Mn2Sin (1≤n≤8) have been carried out within a gradient corrected density-functional framework. We find that Cr2Sin clusters containing up to five Si atoms and Mn2Sin clusters containing up to eight Si atoms are all marked by finite local spin moments at the transition-metal site that order ferromagnetically or antiferromagnetically depending on the size and the charged state. Our studies of the variation in the binding energy upon addition of successive Si atoms and the gap between the highest occupied molecular orbital and the lowest unoccupied molecular orbital indicate Mn2Si4 to be a potential motif for generating magnetic cluster-assembled material. While the individual Mn2Si4 motif has a ground state with antiferromagnetically coupled local moments, the studies on the assembly of two basic motifs show that it favors a ferromagnetic state. It is hoped that the present work will motivate examination of such assemblies in the recently developed cluster beam deposition experiments
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