21,014 research outputs found
Thermal fission cross section measurements of 243Cm and 245Cm
No full textA new measurement program was set up at SCK-CEN to determine the thermal neutroninduced fission cross section of a number of Cm isotopes. The experiments are performed at a thermal neutron beam from the graphite moderated reactor BR1 at SCK-CEN. This paper presents preliminary results of our ^243Cm(n,f) and ^245Cm(n,f) cross-section measurements
Shading and the landmarks of relief
No full textShading is a visual artist’s tool. It enables the indication of ‘landmarks’ inside the outline of shapes. Shading triggers behavioral responses in organisms throughout the animal kingdom and even affects the habitus of plants. Radiometry might be expected to account for the phenomenology. We derive the formal structures of shading that are expected to play a dominant role in perception. That they fail to do so suggests that shading is more of an interface template than a ‘cue’. This fits the artistic use as a ‘releaser’ very well. Pre-modern artists hardly acknowledge causal relations between various photometric variables. Their works show an effective use of various elements in their own right, without attempts at causal congruity. Modern art often defies physics on purpose. We identify manifest templates and relate these to conventional techniques in the visual arts.sponsorship: This work was supported by a visiting scientist grant from the University of Sassari and the Methusalem program by the Flemish Government (METH/14/02), awarded to Johan Wagemans. (University of Sassari, Flemish Government|METH/14/02)status: Publishe
Determining key clinical predictors for chronic ankle instability and return to sports with cost of illness analysis: protocol of a prospective cohort study
No full textIntroduction Ankle sprains are common in sports and the general population. Although considered innocuous, a large proportion has residual complaints such as recurrent ankle sprains and develop chronic ankle instability. Although some predicting factors are identified, there is no unequivocality regarding the development of chronic ankle instability, nor about the optimal rehabilitation for an acute ankle sprain. Alongside the biomechanical impairments, ankle sprains are a burden on society due to substantial economic costs. Therefore, we aim to identify key clinical predictors of chronic ankle instability or recovery after acute lateral ankle sprain. Additionally, we aim to determine cost-of-illness of patients who developed chronic ankle instability.Methods and analysis This prospective cohort study (Clinicaltrials.gov: NCT05637008 - pre-results) aims to recruit adult (18–55 years) patients with an acute lateral ankle sprain who are active in sports. Clinical assessments and patient-reported outcome measures will be used to collect data at 7–14 days, 6 weeks, 12 weeks and 12 months after enrolment in the study. The primary outcome will be chronic ankle instability at 12-month follow-up. Salient outcomes will be analysed by logistic regression to determine association with the development of chronic ankle instability. Participants will fill in a cost diary containing direct and indirect costs related to their injury.Ethics and disseminations The ethical committee of the Antwerp University Hospital (B3002022000138) has given approval of the protocol and consent forms on 10 October 2022. We perform this study according to the Helsinki Declaration. We will present results at conferences or webinars and publish in peer-reviewed articles.NCT05637008
245Cm fission cross section measurement in the thermal energy region
No full textA new cross section measurement for the ^245Cm(n,f) reaction in the thermal energy region has been performed at the GELINA neutron facility of the Institute for Reference Materials and Measurements (IRMM) in Geel, Belgium. The energy of the neutrons is determined applying the time of flight method using a flight path length of about 9 m. In the present work, the incident neutron energy covers 10 meV up to a few eV. A 98.48% enriched ^245Cm sample was mounted back-to-back with a ^10B sample in the centre of a vacuum chamber together with two surface barrier detectors positioned outside the neutron beam. One detector measured the ^10B(n,a)^7Li reaction products for the neutron flux determination, while the second one registered the ^245Cm(n,f) fragments. In this way, the neutron flux can be determined simultaneously with the fission fragments. A control measurement has been performed replacing the ^245Cm sample with a ^235U sample in order to check that the well-known ^235U(n,f) cross section can be reproduced. Our measurement yielded a ^245Cm(nth,f) cross section of 2131±43±173 b and a Westcott factor gf=0.939±0.019
The nature of the visual field, a phenomenological analysis
No full textThe visual field is the spatial form of visual awareness, that is,immediate visual experience ignoring qualities and meanings. Such an entity only exists in the discursive representation, for the awareness as such is quality and meaning throughout. Thus the discursive, formal treatment is necessarily limited. We identify a number of important distinctions of a geometrical nature. This description is confronted with experimental phenomenology, that is the psychology of the Gestalt Schools, and with well known
principles of artistic practice. We also trace the onnections with biology, especially ethology, aesthetics, and the field of cognitive science based upon Cassirer’s concept of symbolic forms.sponsorship: Jan Koenderink is supported by the Methusalem program by the Flemish Government (METH/08/02), awarded to Johan Wagemans. (Methusalem program by the Flemish Government|METH/08/02)status: Publishe
Jan Kapr's contribution to contemporary music : an essay about a composer and teacher
No full textThis creative project is a treatise on a leading personality of Czechoslovakian musical life, the composer, Jan Kapr. The author discusses the following:1. The complicated development of Kapr's career and work, 2. Kapr's method of organization of musical material in a composition, as described in his book Constants,3. His former and current style which is demonstrated in two of his compositions, Concert Variations, for flute and string orchestra and Testimonies for four solo instruments,4. Two of his recent works, Exercises for Gydli and the Symphony No. 7, Country of Childhood.Thesis (M.A.
Characteristics of light charged particle emission in the ternary fission of 250Cf and 252Cf at different excitation energies
No full textThe emission probabilities and the energy distributions of tritons, α and ^6He particles emitted in the spontaneous ternary fission (zero excitation energy) of ^250Cf and ^252Cf and in the cold neutron induced fission (excitation energy ≈ 6.5 MeV) of ^249Cf and 251Cf are determined. The particle identification was done with suited ΔE-E telescope detectors, at the IRMM (Geel, Belgium) for the spontaneous fission and at the ILL (Grenoble, France) for the neutron induced fission measurements. Hence particle emission characteristics of the fissioning systems ^250Cf and ^252Cf are obtained at zero and at about 6.5 MeV excitation energies. While the triton emission probability is hardly influenced by the excitation energy, the ^4He and ^6He emission probability in spontaneous fission is higher than for neutron induced fission. This can be explained by the strong influence of the cluster preformation probability on the ternary particle emission probability
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
ELEVEN FACES OF JAN GOGOL, JR.
No full textAuthor Jan Rendl in his thesis attempts to look at the world of ideas and educator Jan
Gogola ml. through the eleven chapters in which each chapter somehow characterizes itself by Jan Gogola ml. and each of them somehow determines its creative ideas of it through the metaphor of a football match when Jan Gogola, with its characters, movies himself a teammate, as well as defensively. It gives goals with their situations as well as occasionally digging his opponents ankles.
Jan Gogola ml. thus embodies one stage of the Department of Documentary Film at FAMU, which often stands at the intersection between teaching activities and Karel Vachek among students who applied by them during their seminars psychological methods that work must be peculiarly associated with the author of the film
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