2,372 research outputs found
Inspannings- en monitoringsadviezen voor snoekbaars, baars, blankvoorn en brasem in het IJsselmeer en Markermeer
Het ministerie van Economische Zaken wil voor de bestanden van snoekbaars, baars, blankvoorn en brasem in het IJsselmeer en Markermeer komen tot wetenschappelijk onderbouwd beheer. In een hieraan voorafgaand rapport (Tien en Miller 2013) zijn potentiële vangstadviezen gegeven voor de vier visbestanden. Op basis van deze informatie is het ministerie van Economische Zaken gekomen tot definitieve vangstadviezen. Met de doelstelling om binnen drie jaar verdere achteruitgang in de bestanden te voorkomen is het advies om drie jaar lang de vangsten terug te brengen naar maximaal 37% voor snoekbaars, 69% voor baars, 12% voor brasem en 53% voor blankvoorn van de vangsten van 2012
Exact Solutions for Matter-Enhanced Neutrino Oscillations
The analogy between supersymmetric quantum mechanics and matter-enhanced
neutrino oscillations is exploited to obtain exact solutions for a class of
electron density profiles. This integrability condition is analogous to the
shape-invariance in supersymmetric quantum mechanics. This method seems to be
the most direct way to obtain the exact survival probabilities for a number of
density profiles of interest, such as linear and exponential density profiles.
The resulting neutrino amplitudes can also be utilized as comparison amplitudes
for the uniform semiclassical treatment of neutrino propagation in arbitrary
electron density profiles.Comment: Submitted to Physical Review D. Latex file, 8 pages. This paper is
also available at http://nucth.physics.wisc.edu/preprints
A Study of a Wireless Smart Sensor Platform for Practical Training
[[abstract]]In order to overcome the obstacles in traditional experimenting and practical training courses, as well as in enhancing the functions of the present e-learning system, the study took sensor network technology as the foundation in developing a web services system. The system will be able to make presentations of the students ‘operations and results on an immediate basis, allowing the students to be guided adequately as they face problems during experiment and practical training.[[booktype]]紙
Multifragmentation of charge asymmetric nuclear systems
The multifragmentation of excited spherical nuclear sources with various N/Z
ratios and fixed mass number is studied within dynamical and statistical
models. The dynamical model treats the multifragmentation process as a final
stage of the growth of density fluctuations in unstable expanding nuclear
matter. The statistical model makes a choice of the final multifragment
configuration according to its statistical weight at a global thermal
equilibrium. Similarities and differences in the predictions of the two models
on the isotopic composition of the produced fragments are presented and the
most sensitive observable characteristics are discussed.Comment: 15 pages, 8 figure
Heisenberg exchange enhancement by orbital relaxation in cuprate compounds
We calculate the Heisenberg exchange J in the quasi-2D antiferromagnetic
cuprates La2CuO4, YBa2Cu3O6, Nd2CuO4 and Sr2CuO2Cl2. We apply all-electron
(MC)SCF and non-orthogonal CI calculations to [Cu2O11]18-, [Cu2O9]14-,
[Cu2O7]10- and [Cu2O7Cl4]14- clusters in a model charge embedding. The (MC)SCF
triplet and singlet ground states are well characterized by Cu2+ (dx2-y2) and
O2-. The antiferromagnetic exchange is strongly enhanced by admixing relaxed
(MC)SCF triplet and singlet excited states, in which a single electron is
transferred from the central O ion to Cu. We ascribe this effect to orbital
relaxation in the charge transfer component of the wave function. Close
agreement with experiment is obtained.Comment: publishe
Multiple (inverse) binomial sums of arbitrary weight and depth and the all-order epsilon-expansion of generalized hypergeometric functions with one half-integer value of parameter
We continue the study of the construction of analytical coefficients of the
epsilon-expansion of hypergeometric functions and their connection with Feynman
diagrams. In this paper, we show the following results:
Theorem A: The multiple (inverse) binomial sums of arbitrary weight and depth
(see Eq. (1.1)) are expressible in terms of Remiddi-Vermaseren functions.
Theorem B: The epsilon expansion of a hypergeometric function with one
half-integer value of parameter (see Eq. (1.2)) is expressible in terms of the
harmonic polylogarithms of Remiddi and Vermaseren with coefficients that are
ratios of polynomials. Some extra materials are available via the www at this
http://theor.jinr.ru/~kalmykov/hypergeom/hyper.htmlComment: 24 pages, latex with amsmath and JHEP3.cls; v2: some typos corrected
and a few references added; v3: few references added
H^+ -> W^+ l_i^- l_j^+$ decay in the two Higgs doublet model
We study the lepton flavor violating H^+ -> W^+ l_i^- l_j^+ and the lepton
flavor conserving $H^+ -> W^+ l_i^- l_i^+ (l_i=\tau, l_j=\mu) decays in the
general 2HDM, so called model III. We estimate the decay width \Gamma for LFV
(LFC) at the order of the magnitude of (10^{-11}-10^{-5}) GeV
((10^{-9}-10^{-4}) GeV), for 200 GeV\leq m_{H^\pm}\leq 400
GeV, and the intermediate values of the coupling
\bar{\xi}^{E}_{N,\tau \mu}\sim 5 GeV (\bar{\xi}^{E}_{N,\tau
\tau}\sim 30 GeV). We observe that the experimental result of the process
under consideration can give comprehensive information about the physics beyond
the standard model and the existing free parameters.Comment: 8 pages, 7 Figure
Coastal sedimentation across North America doubled in the 20th century despite river dams
The proliferation of dams since 1950 promoted sediment deposition in reservoirs, which is thought to be starving the coast of sediment and decreasing the resilience of communities to storms and sea-level rise. Diminished river loads measured upstream from the coast, however, should not be assumed to propagate seaward. Here, we show that century-long records of sediment mass accumulation rates (g cm−2 yr−1) and sediment accumulation rates (cm yr−1) more than doubled after 1950 in coastal depocenters around North America. Sediment sources downstream of dams compensate for the river-sediment lost to impoundments. Sediment is accumulating in coastal depocenters at a rate that matches or exceeds relative sea-level rise, apart from rapidly subsiding Texas and Louisiana where water depths are increasing and intertidal areas are disappearing. Assuming no feedbacks, accelerating global sea-level rise will eventually surpass current sediment accumulation rates, underscoring the need for including coastal-sediment management in habitat-restoration projects
Implementation of Quality Systems in Nuclear Medicine: Why It Matters. An Outcome Analysis (Quality Management Audits in Nuclear Medicine Part III).
The International Atomic Energy Agency (IAEA) developed a comprehensive program-Quality Management Audits in Nuclear Medicine (QUANUM). This program covers all aspects of nuclear medicine practices including, but not limited to, clinical practice, management, operations, and services. The QUANUM program, which includes quality standards detailed in relevant checklists, aims at introducing a culture of comprehensive quality audit processes that are patient oriented, systematic, and outcome based. This paper will focus on the impact of the implementation of QUANUM on daily routine practices in audited centers. Thirty-seven centers, which had been externally audited by experts under IAEA auspices at least 1 year earlier, were invited to run an internal audit using the QUANUM checklists. The external audits also served as training in quality management and the use of QUANUM for the local teams, which were responsible of conducting the internal audits. Twenty-five out of the 37 centers provided their internal audit report, which was compared with the previous external audit. The program requires that auditors score each requirement within the QUANUM checklists on a scale of 0-4, where 0-2 means nonconformance and 3-4 means conformance to international regulations and standards on which QUANUM is based. Our analysis covering both general and clinical areas assessed changes on the conformance status on a binary manner and the level of conformance scores. Statistical analysis was performed using nonparametric statistical tests. The evaluation of the general checklists showed a global improvement on both the status and the levels of conformances (P < 0.01). The evaluation of the requirements by checklist also showed a significant improvement in all, with the exception of Hormones and Tumor marker determinations, where changes were not significant. Of the 25 evaluated institutions, 88% (22 of 25) and 92% (23 of 25) improved their status and levels of conformance, respectively. Fifty-five requirements, on average, increased from nonconformance to conformance status. In 8 key areas, the number of improved requirements was well above the average: Administration & Management (checklist 2); Radiation Protection & Safety (checklist 4); General Quality Assurance system (checklist 6); Imaging Equipment Quality Assurance or Quality Control (checklist 7); General Diagnostic (checklist 9); General Therapeutic (checklist 12); Radiopharmacy Level 1 (checklist 14); and Radiopharmacy Level 2 (checklist 15). Analysis of results related to clinical activities showed an overall positive impact on both the status and the level of conformance to international standards. Similar results were obtained for the most frequently performed clinical imaging and therapeutic procedures. Our study shows that the implementation of a comprehensive quality management system through the IAEA QUANUM program has a positive impact on nuclear medicine practices
Evidence for Color Fluctuations in Hadrons from Coherent Nuclear Diffraction}
A QCD-based treatment of projectile size fluctuations is used to compute
inelastic diffractive cross sections for coherent
hadron-nuclear processes. We find that fluctuations near the average size give
the major contribution to the cross section with contribution
from small size configurations.
The computed values of are consistent with the limited
available data. The importance of coherent diffraction studies for a wide range
of projectiles for high energy Fermilab fixed target experiments is emphasized.
The implications of these significant color fluctuations for relativistic heavy
ion collisions are discussed.Comment: Report number DOE/ER 40427-13-N93 11 pages, 3 figures available from
author Mille
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