831 research outputs found
Monolithic flux transformer-coupled high-Tc dc SQUID magnetometers
YBa/sub 2/Cu/sub 3/O/sub 7-x/ based monolithic flux transformer-coupled high-T/sub c/ DC SQUID magnetometers operating up to 73 K have been realized. The devices are characterized by high values of the modulation voltage, up to 32 /spl mu/V at 40 K. A minimal white noise level of 0.10 pT//spl radic/Hz was obtained above 200 Hz, and 0.64 pT//spl radic/Hz at 1 Hz and 55 K. The temperature dependence of the modulation voltage, the effective sensing area and the field sensitivity are discussed. Model-calculations have been performed to investigate high frequency resonances in the washer-input coil structure. Methods for damping are considered
Linking Farm and Market Models to Analyse the Effects of the EU Nitrate Directive for the Dutch Agricultural Sector
This paper presents a modeling system that can be used to analyze the trade off between economy and environment. It takes into account manure policy, farm structure and manure surpluses at farm level as well as the economic effects of manure surpluses at market level. The modeling system consists of two models that are linked to each other by at the one-hand manure prices and distribution of manure over different destinations and at the other hand changes in agricultural and total manure production. One model is the so-called Manure and Ammonia Model (MAM). This model calculates manure surpluses and deficits at the farm level and distribution of manure to own farm, own region, other regions, export abroad and processing at the regional level. Moreover, MAM also calculates ammonia emissions coming from different sources. The second model is a market model that includes the most important agricultural markets. The models are calibrated for 2002. The modeling system is tested to analyze the effects of sharpened manure policies until 2006.farm models, market models, manure, economy, policy, Agricultural and Food Policy,
Instrumentarium monitoring mestmarkt en enkele analyses
Het nieuwe mestbeleid met daarin een stelsel van gebruiksnormen en de bijbehorende normen grijpen naar verwachting fors in op de mestmarkt. Dit rapport beschrijft onderdelen van het instrumentarium voor de monitoring van de mestmarkt. De onderdelen zijn analyses van derogatiebedrijven (1), van de acceptatie van dierlijke mest op kleiakkerbouwbedrijven (2) en van het gedrag van melkveehouders op het nieuwe mestbeleid (3). Daarnaast beschrijft het rapport de opzet voor een systeem voor monitoring van mestprijzen (4) en de opzet voor interviews met mestdistributeurs (5)
Scheduling with step-improving processing times
2005-2006 > Academic research: refereed > Publication in refereed journalAccepted ManuscriptPublishe
Scheduling Bidirectional Traffic on a Path
We study the fundamental problem of scheduling bidirectional traffic along a
path composed of multiple segments. The main feature of the problem is that
jobs traveling in the same direction can be scheduled in quick succession on a
segment, while jobs in opposing directions cannot cross a segment at the same
time. We show that this tradeoff makes the problem significantly harder than
the related flow shop problem, by proving that it is NP-hard even for identical
jobs. We complement this result with a PTAS for a single segment and
non-identical jobs. If we allow some pairs of jobs traveling in different
directions to cross a segment concurrently, the problem becomes APX-hard even
on a single segment and with identical jobs. We give polynomial algorithms for
the setting with restricted compatibilities between jobs on a single and any
constant number of segments, respectively
Embracing complexity in international forest governance: a way forward; Policy Brief
This Policy Brief summarizes the findings of a comprehensive assessment of scientific information about international forest governance carried out by an Expert Panel of over 30 of the world's leading scientists working in the areas of environmental governance and international forest law. It aims to provide policy and decision makers with essential knowledge and building blocks required for a more effective and inclusive governance of the world's forest
Controlled auction in het Nederlandse rechtsbestel: De verhouding tussen de contractsvrijheid en de precontractuele fase
Coherent privaatrech
A New Proposal for the Picture Changing Operators in the Minimal Pure Spinor Formalism
Using a new proposal for the "picture lowering" operators, we compute the
tree level scattering amplitude in the minimal pure spinor formalism by
performing the integration over the pure spinor space as a multidimensional
Cauchy-type integral. The amplitude will be written in terms of the projective
pure spinor variables, which turns out to be useful to relate rigorously the
minimal and non-minimal versions of the pure spinor formalism. The natural
language for relating these formalisms is the Cech-Dolbeault isomorphism.
Moreover, the Dolbeault cocycle corresponding to the tree-level scattering
amplitude must be evaluated in SO(10)/SU(5) instead of the whole pure spinor
space, which means that the origin is removed from this space. Also, the
Cech-Dolbeault language plays a key role for proving the invariance of the
scattering amplitude under BRST, Lorentz and supersymmetry transformations, as
well as the decoupling of unphysical states. We also relate the Green's
function for the massless scalar field in ten dimensions to the tree-level
scattering amplitude and comment about the scattering amplitude at higher
orders. In contrast with the traditional picture lowering operators, with our
new proposal the tree level scattering amplitude is independent of the constant
spinors introduced to define them and the BRST exact terms decouple without
integrating over these constant spinors.Comment: 56 pages, typos correcte
Topsector Agro&Food : 'Agro&Food: De Nederlandse groeidiamant'
Innovatiecontract van de Topsector Agri&Food. De Agro & Food sector is de motor van de Nederlandse economie en de nummer 1 in de wereld. In totaal genereert de sector €48 miljard aan toegevoegde waarde. Dat is goed voor bijna 10% van de Nederlandse economie en werkgelegenheid. Nederland heeft de meest succesvolle en innovatieve Agro & Food-bedrijven, beschikt over kennisinstellingen van wereldklasse en staat aan de Europese top van private investeringen
- …