8,012 research outputs found

    Open educational practices for curriculum enhancement

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    Open educational resources (OER) and open educational practices (OEP) are relatively new areas in educational research. How OER and OEP can help practitioners enhance curricula is one of a number of under-researched topics. This article aims to enable practitioners to identify and implement appropriate open practices to enhance higher education curricula. To that aim, we put forward a framework of four open educational practices based on patterns of OER reuse (‘as is’ or adapted), mapped against the processes of curriculum design and delivery. The framework was developed from the in-depth analysis of 20 cases of higher education practitioners, which revealed patterns of OER reuse across disciplines, institutions and needs. For each open practice we offer evidence, examples and ideas for application by practitioners. We also put forward recommendations for institutional policies on OER and OE

    Mobilizing Public Will For Social Change

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    Examines the theory and strategies of "public will" campaigns and offers tangible criteria for their evaluation. It provides a rich inventory of strategies for use in mobilizing the public will through an integration of models of agenda building, social problem construction, issues management, social movements, media advocacy, and social capital. In addition, the paper provides cases and examples of public will campaigns directed at various social problems, along with criteria for evaluating these campaigns at various stages of a social problem's life cycle

    The interpretation of spikes and trends in concentration of nitrate in polar ice cores, based on evidence from snow and atmospheric measurements

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    Nitrate is frequently measured in ice cores, but its interpretation remains immature. Using daily snow surface concentrations of nitrate at Halley (Antarctica) for 2004 - 2005, we show that sharp spikes (> factor 2) in nitrate concentration can occur from day to day. Some of these spikes will be preserved in ice cores. Many of them are associated with sharp increases in the concentration of sea salt in the snow. There is also a close association between the concentrations of aerosol nitrate and sea salt aerosol. This evidence is consistent with many of the spikes in deposited nitrate being due to the conversion or trapping of gas- phase nitrate, i. e. to enhanced deposition rather than enhanced atmospheric concentrations of NOy. Previously, sharp spikes in nitrate concentration (with concentration increases of up to a factor 4 seen in probably just one snowfall) have been assigned to sharp production events such as solar proton events (SPEs). We find that it is unlikely that SPEs can produce spikes of the kind seen. Taken together with our evidence that such spikes can be produced depositionally, we find that it is not possible to track past SPEs without carrying out a new multi- site and multi- analyte programme. Seasonal and interannual trends in nitrate concentration in cores from any single site cannot be interpreted in terms of production changes until the recycling of nitrate from central Antarctica to coastal Antarctica is better quantified. It might be possible to assess the interannual input of NOy to the Antarctic lower troposphere by using a network of cores to estimate variability in the total annual deposition across the continent (which we estimate to be 9 +/- 2 x 10(7) kg/a - as NO3-), but it will first have to be established that the outflow across the coast can be ignored

    Energetics, skeletal dynamics and long-term predictions in Kolmogorov-Lorenz systems

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    We study a particular return map for a class of low dimensional chaotic models called Kolmogorov Lorenz systems, which received an elegant general Hamiltonian description and includes also the famous Lorenz63 case, from the viewpoint of energy and Casimir balance. In particular it is considered in detail a subclass of these models, precisely those obtained from the Lorenz63 by a small perturbation on the standard parameters, which includes for example the forced Lorenz case in Ref.[6]. The paper is divided into two parts. In the first part the extremes of the mentioned state functions are considered, which define an invariant manifold, used to construct an appropriate Poincare surface for our return map. From the experimental observation of the simple orbital motion around the two unstable fixed points, together with the circumstance that these orbits are classified by their energy or Casimir maximum, we construct a conceptually simple skeletal dynamics valid within our sub class, reproducing quite well the Lorenz map for Casimir. This energetic approach sheds some light on the physical mechanism underlying regime transitions. The second part of the paper is devoted to the investigation of a new type of maximum energy based long term predictions, by which the knowledge of a particular maximum energy shell amounts to the knowledge of the future (qualitative) behaviour of the system. It is shown that, in this respect, a local analysis of predictability is not appropriate for a complete characterization of this behaviour. A perspective on the possible extensions of this type of predictability analysis to more realistic cases in (geo)fluid dynamics is discussed at the end of the paper.Comment: 21 pages, 14 figure

    Kedudukan dan Kewenangan Dewan Perwakilan Daerah dalam Sistem Ketatanegaraan Indonesia

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    Functioned as a regional representative council, DPD possessing a regional representative character principally has a broader representative character compared to DPR (Legislative Assembly). It is because its representative dimensions are based on all of the citizens living in the regions. The issues being studied include (1) Is the existence of DPD in line with the idea of its establishment based on the bicameral legislative system?, (2) Is the constitutional authority of DPD synchronic with its existence as a state institution? This is a normative research focused on primary and secondary materials of law including the regulation of law and the literatures relevant as the research object. In obtaining the primary and secondary materials, a library research was conducted by involving a descriptive-qualitativeanalysis. The research result then shows the existence of DPD in relationship with DPR and MPR as regulated in the Constitution of 1945 is not in line with the thought of its establishment. At this point, the reform on the structure of Indonesia Constitution toward a strong bicameralism is not materialized in the Constitution of 1945

    Vortex line representation for flows of ideal and viscous fluids

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    It is shown that the Euler hydrodynamics for vortical flows of an ideal fluid coincides with the equations of motion of a charged {\it compressible} fluid moving due to a self-consistent electromagnetic field. Transition to the Lagrangian description in a new hydrodynamics is equivalent for the original Euler equations to the mixed Lagrangian-Eulerian description - the vortex line representation (VLR). Due to compressibility of a "new" fluid the collapse of vortex lines can happen as the result of breaking (or overturning) of vortex lines. It is found that the Navier-Stokes equation in the vortex line representation can be reduced to the equation of the diffusive type for the Cauchy invariant with the diffusion tensor given by the metric of the VLR

    Slow flows of an relativistic perfect fluid in a static gravitational field

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    Relativistic hydrodynamics of an isentropic fluid in a gravitational field is considered as the particular example from the family of Lagrangian hydrodynamic-type systems which possess an infinite set of integrals of motion due to the symmetry of Lagrangian with respect to relabeling of fluid particle labels. Flows with fixed topology of the vorticity are investigated in quasi-static regime, when deviations of the space-time metric and the density of fluid from the corresponding equilibrium configuration are negligibly small. On the base of the variational principle for frozen-in vortex lines dynamics, the equation of motion for a thin relativistic vortex filament is derived in the local induction approximation.Comment: 4 pages, revtex, no figur

    Shear-banding in a lyotropic lamellar phase, Part 2: Temporal fluctuations

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    We analyze the temporal fluctuations of the flow field associated to a shear-induced transition in a lyotropic lamellar phase: the layering transition of the onion texture. In the first part of this work [Salmon et al., submitted to Phys. Rev. E], we have evidenced banded flows at the onset of this shear-induced transition which are well accounted for by the classical picture of shear-banding. In the present paper, we focus on the temporal fluctuations of the flow field recorded in the coexistence domain. These striking dynamics are very slow (100--1000s) and cannot be due to external mechanical noise. Using velocimetry coupled to structural measurements, we show that these fluctuations are due to a motion of the interface separating the two differently sheared bands. Such a motion seems to be governed by the fluctuations of σ⋆\sigma^\star, the local stress at the interface between the two bands. Our results thus provide more evidence for the relevance of the classical mechanical approach of shear-banding even if the mechanism leading to the fluctuations of σ⋆\sigma^\star remains unclear

    Surface compositional mapping by spectral ratioing of ERTS-1 MSS data in the Wind River Basin and Range, Wyoming

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    The author has identified the following significant results. ERTS data collected in August and October 1972 were processed on digital and special purpose analog recognition computers using ratio enhancement and pattern recognition. Ratios of band-averaged laboratory reflectances of some minerals and rock types known to be in the scene compared favorably with ratios derived from the data by ratio normalization procedures. A single ratio display and density slice of the visible channels of ERTS MSS data, Channel 5/Channel 4 (R5,4), separated the Triassic Chugwater formation (redbeds) from other formations present and may have enhanced iron oxide minerals present at the surface in abundance. Comparison of data sets collected over the same area at two different times of the year by digital processing indicated that spectral variation due to environmental factors was reduced by ratio processing
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