A generalized empirical interpolation method : application of reduced basis techniques to data assimilation

In an effort to extend the classical lagrangian interpolation tools, new interpolating methods that use general interpolating functions are explored. The method analyzed in this paper, called Generalized Empirical Interpolation Method (GEIM), belongs to this class of new techniques. It generalizes the plain Empirical Interpolation Method by replacing the evaluation at interpolating points by application of a class of interpolating linear functions. The paper is divided into two parts: first, the most basic properties of GEIM (such as the well-posedness of the generalized interpolation problem that is derived) will be analyzed. On a second part, a numerical example will illustrate how GEIM, if considered from a reduced basis point of view, can be used for the real-time reconstruction of experiments by coupling data assimilation with numerical simulations in a domain decomposition framework

Overcoming the barriers to implementing urban road user charging schemes

Urban road user charging offers the potential to achieve significant improvements in urban transport, but is notoriously difficult to implement. Cities need guidance on the range of factors to be considered in planning and implementing such schemes. This paper summarises the results of a 3 year programme which has collated evidence on the issues of most concern to cities. A state of the art report has provided evidence on 14 themes, ranging from objectives and design to implementation and evaluation. A set of 16 case studies has reviewed experience in design and implementation across Europe. The paper summarises their findings, provides references to more detailed information, presents the resulting policy recommendations to European, national and local government, and outlines the areas in which further research is needed

Damping of liquid sloshing by foams

When a container is set in motion, the free surface of the liquid starts to oscillate or slosh. Such effects can be observed when a glass of water is handled carelessly and the fluid sloshes or even spills over the rims of the container. However, beer does not slosh as readily as water, which suggests that foam could be used to damp sloshing. In this work, we study experimentally the effect on sloshing of a liquid foam placed on top of a liquid bath. We generate a monodisperse two-dimensional liquid foam in a rectangular container and track the motion of the foam. The influence of the foam on the sloshing dynamics is experimentally characterized: only a few layers of bubbles are sufficient to significantly damp the oscillations. We rationalize our experimental findings with a model that describes the foam contribution to the damping coefficient through viscous dissipation on the walls of the container. Then we extend our study to confined three-dimensional liquid foam and observe that the behavior of 2D and confined 3D systems are very similar. Thus we conclude that only the bubbles close to the walls have a significant impact on the dissipation of energy. The possibility to damp liquid sloshing using foam is promising in numerous industrial applications such as the transport of liquefied gas in tankers or for propellants in rocket engines.Comment: 17 pages, accepted in Physics of Fluid

2022 Top Trends in Academic Libraries

This article summarizes trending topics in academic librarianship from the past two years–a time of tremendous upheaval and change, including a global pandemic, difficult reflections concerning racial justice, and war between nation states. Rapid changes and uncertainty from these events have created a significant amount of shifts to academic libraries, higher education, and society in general. Such shifts have yielded new perspectives and innovations in how librarians approach delivering services, supporting student success, managing staff and physical spaces, embracing new technology, and managing data. This report attempts to provide a snapshot of developments worth noting

Expression of Distal-less, dachshund, and optomotor blind in Neanthes arenaceodentata (Annelida, Nereididae) does not support homology of appendage-forming mechanisms across the Bilateria

The similarity in the genetic regulation of arthropod and vertebrate appendage formation has been interpreted as the product of a plesiomorphic gene network that was primitively involved in bilaterian appendage development and co-opted to build appendages (in modern phyla) that are not historically related as structures. Data from lophotrochozoans are needed to clarify the pervasiveness of plesiomorphic appendage forming mechanisms. We assayed the expression of three arthropod and vertebrate limb gene orthologs, Distal-less (Dll), dachshund (dac), and optomotor blind (omb), in direct-developing juveniles of the polychaete Neanthes arenaceodentata. Parapodial Dll expression marks premorphogenetic notopodia and neuropodia, becoming restricted to the bases of notopodial cirri and to ventral portions of neuropodia. In outgrowing cephalic appendages, Dll activity is primarily restricted to proximal domains. Dll expression is also prominent in the brain. dac expression occurs in the brain, nerve cord ganglia, a pair of pharyngeal ganglia, presumed interneurons linking a pair of segmental nerves, and in newly differentiating mesoderm. Domains of omb expression include the brain, nerve cord ganglia, one pair of anterior cirri, presumed precursors of dorsal musculature, and the same pharyngeal ganglia and presumed interneurons that express dac. Contrary to their roles in outgrowing arthropod and vertebrate appendages, Dll, dac, and omb lack comparable expression in Neanthes appendages, implying independent evolution of annelid appendage development. We infer that parapodia and arthropodia are not structurally or mechanistically homologous (but their primordia might be), that Dll’s ancestral bilaterian function was in sensory and central nervous system differentiation, and that locomotory appendages possibly evolved from sensory outgrowths

Why do we need a theory and metrics of technology upgrading?

This paper discusses why we need theory and metrics of technology upgrading. It critically reviews the existing approaches to technology upgrading and motivates build-up of theoretically relevant but empirically grounded middle level conceptual and statistical framework which could illuminate a type of challenges relevant for economies at different income levels. It conceptualizes technology upgrading as three dimensional processes composed of intensity and different types of technology upgrading through various types of innovation and technology activities; broadening of technology upgrading through different forms of technology and knowledge diversification, and interaction with global economy through knowledge import, adoption and exchange. We consider this to be necessary first step towards theory and metrics of technology upgrading and generation of more relevant composite indicator of technology upgrading

Amorphous formulations of indomethacin and griseofulvin prepared by electrospinning

Following an array of optimization experiments, two series of electrospun polyvinylpyrrolidone (PVP) fibers were prepared. One set of fibers contained various loadings of indomethacin, known to form stable glasses, and the other griseofulvin (a poor glass former). Drug loadings of up to 33% w/w were achieved. Electron microscopy data showed the fibers largely to comprise smooth and uniform cylinders, with evidence for solvent droplets in some samples. In all cases, the drug was found to exist in the amorphous physical state in the fibers on the basis of X-ray diffraction and differential scanning calorimetry (DSC) measurements. Modulated temperature DSC showed that the relationship between a formulation’s glass transition temperature (<i>T</i>_g) and the drug loading follows the Gordon–Taylor equation, but not the Fox equation. The results of Gordon–Taylor analysis indicated that the drug/polymer interactions were stronger with indomethacin. The interactions between drug and polymer were explored in more detail using molecular modeling simulations and again found to be stronger with indomethacin; the presence of significant intermolecular forces was further confirmed using IR spectroscopy. The amorphous form of both drugs was found to be stable after storage of the fibers for 8 months in a desiccator (relative humidity <25%). Finally, the functional performance of the fibers was studied; in all cases, the drug-loaded fibers released their drug cargo very rapidly, offering accelerated dissolution over the pure drug

Social welfare analysis of investment public-private partnership approaches for tansportation projects

This paper has two objectives: (1) to introduce a new approach to gaining widespread support for comprehensive road pricing; and (2) to develop a detailed social welfare analysis for road pricing schemes. We first describe a new approach to garnering support for system-wide road pricing, which we refer to as an investment public-private partnership, or IP3. This approach returns a significant portion of the economic value created by road pricing back to its citizen-owners. Next, we present a social welfare framework that estimates the benefits and costs of using the IP3 approach on an urban transportation network. Policy makers typically evaluate public-private partnership (P3) projects using Value for Money (VfM) analysis. However, a P3 project's impact on overall social welfare provides a more comprehensive evaluation criterion. Apart from several theoretical studies, a detailed social welfare analysis that includes all major P3 project stakeholders is lacking. Using Fresno City's transportation system as our case study, we show that system-optimal tolling scenarios favor average users, but that government¿and consequently taxpayers¿would pay for costly tolling systems. In contrast, unlimited profit-maximizing tolls raise substantial profits for government, for the infrastructure's citizen-owners, and for the private sector, but the average user is worse off. From a social welfare perspective, one should search for a Pareto-improvement under which all major stakeholders are better off. Our estimates indicate that a mixed private and public tolling scheme offers such an improvement. A mixed scheme results in the highest social welfare among all scenarios unless the weight placed on motorists' (i.e., transportation users') welfare is very low or the weight placed on residents' welfare is very high relative to the weight of other stakeholders

Perception of limb orientation in the vertical plane depends on center of mass rather than inertial eigenvectors

We performed two experiments to test the hypothesis that the perception of limb orientation depends on inertial eigenvectors (