684 research outputs found

    The pion form factor from first principles

    Full text link
    We calculate the electromagnetic form factor of the pion in quenched lattice QCD. The non-perturbatively improved Sheikoleslami-Wohlert lattice action is used together with the O(a){\mathcal O}(a) improved current. We calculate form factor for pion masses down to mπ=360MeVm_\pi = 360 MeV. We compare the mean square radius for the pion extracted from our form factors to the value obtained from the 'Bethe Salpeter amplitude'. Using (quenched) chiral perturbation theory, we extrapolate our results towards the physical pion mass.Comment: 5 pages, 2 figures; proceedings of Hadron03, Aschaffenburg, German

    Seaweed as feed supplement (OK-Net EcoFeed Practice Abstract)

    Get PDF
    • Effectivity might differ depending on the seaweed type, harvest season and processing method. Brown and red seaweed species may be better than green. • Several commercial seaweed products can be used, and it is important to ask for documentation of effect before relying on e.g. effect on diarrhoea. • High levels of macro and micro minerals have to be taken into account when composing diets with seaweed. • Many seaweed extracts are available, which may not be suitable for organic production

    Starfish as feedstuff (OK-Net Ecofeed Practice Abstract)

    Get PDF
    • Starfish should be harvested, at the earliest, three months before spawning to have highest protein and lowest ash content. • High calcium levels limit the inclusion level of starfish meal in piglets’ diets to around 5%. • Starfish meal is not organically certified but can still be used because it is not of agricultural origin. • Starfish meal is already commercially available in Denmark. • Diets can be optimized regarding amino acids and with lower crude protein

    Marketing orientation and strategies in the Netherlands

    Get PDF
    This paper introduces a general, formal treatment of dynamic constraints, i.e., constraints on the state changes that are allowed in a given state space. Such dynamic constraints can be seen as representations of "real world" constraints in a managerial context. The notions of transition, reversible and irreversible transition, and transition relation will be introduced. The link with Kripke models (for modal logics) is also made explicit. Several (subtle) examples of dynamic constraints will be given. Some important classes of dynamic constraints in a database context will be identified, e.g. various forms of cumulativity, non-decreasing values, constraints on initial and final values, life cycles, changing life cycles, and transition and constant dependencies. Several properties of these dependencies will be treated. For instance, it turns out that functional dependencies can be considered as "degenerated" transition dependencies. Also, the distinction between primary keys and alternate keys is reexamined, from a dynamic point of view.

    Evaluation of Cognitive Architectures for Cyber-Physical Production Systems

    Full text link
    Cyber-physical production systems (CPPS) integrate physical and computational resources due to increasingly available sensors and processing power. This enables the usage of data, to create additional benefit, such as condition monitoring or optimization. These capabilities can lead to cognition, such that the system is able to adapt independently to changing circumstances by learning from additional sensors information. Developing a reference architecture for the design of CPPS and standardization of machines and software interfaces is crucial to enable compatibility of data usage between different machine models and vendors. This paper analysis existing reference architecture regarding their cognitive abilities, based on requirements that are derived from three different use cases. The results from the evaluation of the reference architectures, which include two instances that stem from the field of cognitive science, reveal a gap in the applicability of the architectures regarding the generalizability and the level of abstraction. While reference architectures from the field of automation are suitable to address use case specific requirements, and do not address the general requirements, especially w.r.t. adaptability, the examples from the field of cognitive science are well usable to reach a high level of adaption and cognition. It is desirable to merge advantages of both classes of architectures to address challenges in the field of CPPS in Industrie 4.0

    Mobilizing the Temporary Organization: The Governance Roles of Selection and Pricing

    Get PDF
    Many marketing transactions between buyers and suppliers involve short-term collaborations or so-called temporary organizations. Such organizations have considerable value-creation potential but also face challenges, as evidenced by their mixed performance records. One particular challenge involves relationship governance, and in this respect, temporary organizations represent a conundrum: On the one hand, they pose significant governance problems due to the need to manage numerous independent specialists under time constraints. On the other hand, temporary organizations lack the inherent governance properties of other organizational forms such as permanent organizations. The authors conduct an empirical study of 429 business-to-business construction projects designed to answer two specific questions: First, how are particular selection and pricing strategies deployed in response to monitoring and coordination problems? Second, does the joint alignment between the two mechanisms and their respective attributes help mitigate cost overruns? The authors follow a formal hypothesis test with a series of in-depth interviews to explore and to gain insight into the validity of the key constructs, explanatory mechanisms, and outcomes. Managerially, the authors answer the long-standing question of how to mobilize a temporary organization. Theoretically, they develop an augmented “discriminating alignment” heuristic for relationship management involving multiple governance mechanisms and attributes.acceptedVersio
    • …
    corecore