3,851 research outputs found
A Collaborative Workflow for Digitization of Unique Materials
This paper examines the experience of one institution, the University of Maryland Libraries, as it made organizational efforts to harness existing workflows and to capture digitization done in the course of responding to patron requests. By examining the way this organization adjusted its existing workflows to put in place more systematic methods for digital capture of unique collections, the authors hope to provide insight into the benefits and pitfalls of one model for scaling up digitization
A Collaborative Workflow for Digitization of Unique Materials
This paper examines the experience of one institution, the University of Maryland Libraries, as it made organizational efforts to harness existing workflows and to capture digitization done in the course of responding to patron requests. By examining the way this organization adjusted its existing workflows to put in place more systematic methods for digital capture of unique collections, the authors hope to provide insight into the benefits and pitfalls of one model for scaling up digitization
Mixed lipid bilayers with locally varying spontaneous curvature and bending
A model of lipid bilayers made of a mixture of two lipids with different
average compositions on both leaflets, is developed. A Landau hamiltonian
describing the lipid-lipid interactions on each leaflet, with two lipidic
fields and , is coupled to a Helfrich one, accounting for the
membrane elasticity, via both a local spontaneous curvature, which varies as
, and a bending modulus equal to
. This model allows us to define curved
patches as membrane domains where the asymmetry in composition,
, is large, and thick and stiff patches where is
large. These thick patches are good candidates for being lipidic rafts, as
observed in cell membranes, which are composed primarily of saturated lipids
forming a liquid-ordered domain and are known to be thick and flat
nano-domains. The lipid-lipid structure factors and correlation functions are
computed for globally spherical membranes and planar ones. Phase diagrams are
established, within a Gaussian approximation, showing the occurrence of two
types of Structure Disordered phases, with correlations between either curved
or thick patches, and an Ordered phase, corresponding to the divergence of the
structure factor at a finite wave vector. The varying bending modulus plays a
central role for curved membranes, where the driving force is
balanced by the line tension, to form raft domains of size ranging from 10 to
100~nm. For planar membranes, raft domains emerge via the cross-correlation
with curved domains. A global picture emerges from curvature-induced
mechanisms, described in the literature for planar membranes, to coupled
curvature- and bending-induced mechanisms in curved membranes forming a closed
vesicle
WORLD CEREALS MARKETS UNDER ALTERNATIVE COMMON AGRICULTURAL POLICY REFORMS
Previous quantitative assessments of likely impacts of recent reforms of the Common Agricultural Policy (in particular the Agenda 2000) differ across empirical studies. Differences are mainly due to the ways the policy instruments are taken into account (explicit modeling or implicit modeling i.e. using ad-valorem equivalents). The aim of this paper is to assess empirically the impacts of recent reforms of the Common Agricultural Policy and the consequences of the Mid-Term proposals on world cereals markets. We develop an econometric, dynamic, multi-product, partial equilibrium commodity model that focuses on arable crops. Major exporters and major importers are modeled separately, other countries being included in a "rest of the world" category. For the countries or regions explicitly integrated the model estimates supply, demand and trade. The model we develop has two important features: i) the parameters estimated in the behavioral equations (supply and demand) satisfy regularity conditions and ii) the agricultural policy instruments (in particular CAP instruments) are modeled in an explicit way. In the empirical section, attention focuses on the world cereals market. We provide a market outlook through the year 2009 for three different scenarios: baseline projections and two scenarios based on different assumptions regarding the evolution of the Common Agricultural Policy (the Mid-Term Review scenario and the decoupling scenario). Estimated effects of the mid-term scenario on EU crop prices depend on the relationship between EU and world market prices.Agricultural and Food Policy,
Start-ups in entrepreneurial ecosystems: the role of relational capacity
Purpose: Entrepreneurial ecosystems provide the context for start-ups to access resources. The authors investigate the reliance of start-ups on their entrepreneurial ecosystem and the driving factors behind the proportion of local actors (belonging to their entrepreneurial ecosystem) within their overall set of relationships (their business ecosystem). Recognizing the limited relational capacity of firms, the authors focus on three differentiating firm characteristics: size, age and innovation of firms. Design/methodology/approach: The authors developed a sample of 163 start-ups located in the entrepreneurial ecosystem of Toulouse, France. The authors investigated the characteristics of their relationship sets using regression analysis. Findings: The results confirm that age is inversely related to the proportion of a start-up's relationships located in its entrepreneurial ecosystem. More surprisingly, for older start-ups, the authors also highlight the presence of a moderating effect of the start-up's size on the relationship between its degree of innovation and the proportion of its relationships in its entrepreneurial ecosystem: Larger and more innovative start-ups appear to rely more on their local entrepreneurial ecosystem. Originality/value: This research increases the understanding of the characteristics driving the interactions of start-ups with their entrepreneurial ecosystems by adopting a relational capacity approach. The authors introduce digital methods as an innovative approach for uncovering firms' ecosystems. Finally, from a practical point of view, the research should provide public authorities seeking to promote the link between local resources and the development of innovative start-ups in their regions with interesting insights
Digitized Special Collections and Multiple User Groups
Many organizations have evolved since their early attempts to mount digital exhibits on the Web and are experimenting with ways to increase the scale of their digitized collections by utilizing archival finding aid description rather than resource-intensive collections and exhibits. This article examines usability research to predict how such systems might effectively be used and highlights a digital library and finding aid system that utilizes a single repository of digitized objects to fuel two types of user-discovery systems: a typical digital collections interface with item-level access and a finding aid that incorporates digitized items at the aggregate level
Wandering of the modal parameters in existing building: application to structural health monitoring
International audienceAmbient vibrations in building is of increasing interest for applications in mechanical engineering, civil engineering and earthquake engineering. With advances in data acquisition systems (number of measurement points, continuous recording, low-noise instrument) and advances in signal processing algorithms, further and better studies can be conducted on civil engineering structures for evaluating their modal parameters and their physical properties. This study is focused on long- and short-term variations of frequency and damping in buildings. After a brief overview of the physical meanings and the practical interest for earthquake engineering, some examples are shown. They concerns the transient variations of modal parameters related with non-linear behaviour of the system, the permanent decrease of frequency and damping after extrem event and the natural wandering of modal parameters, often related to atmospheric conditions. These changes, however, confirms the great stability and confidence measurements in buildings using modal analysis. This information helps to consider the relevancy of analysis of existing monitoring (damage, ageing, and so on) and can better calibrate the mechanical models used for the analysis of seismic vulnerability of existing structures, and thereby help reduce variability of their estimates
On Robustness in Cosmological Simulations
The Cold Dark Matter model faces many controversies at small scales, as simulations fail to reproduce the observed properties of dark matter (DM) haloes. Since rival DM models differ on their predictions about the structure of DM haloes, understanding their mass distribution is crucial for determining the nature of dark matter. However, only numerical approaches to determining what a hypothesis implies for the mass distribution are possible. Hence, simulations are a crucial part of evaluating DM rival models, as is assessing their reliability. I argue that robustness analysis is not a sufficient criterion for the trustworthiness of cosmological simulations
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