On neutron number dependence of B(E1;0+ --> 1-) reduced transition probability

A neutron number dependence of the E1 0+ --> 1- reduced transition probability in spherical even--even nuclei is analysed within the Q--phonon approach in the fermionic space to describe the structure of collective states. Microscopic calculations of the E1 0+ --> 1- transition matrix elements are carried out for the Xe isotopes based on the RPA for the ground state wave function. A satisfactory description of the experimental data is obtained.Comment: 8 pages, 4 figure

iObserve: Integrated Observation and Modeling Techniques to Support Adaptation and Evolution of Software Systems

The goal of iObserve is to develop methods and tools to support evolution and adaptation of long-lived software systems. Future long-living software systems will be engineered using third-party software services and infrastructures. Key challenges for such systems will be caused by dynamic changes of deployment options on cloud platforms. Third-party services and infrastructures are neither owned nor controlled by the users and developers of service-based systems. System users and developers are thus only able to observe third-party services and infrastructures via their interface, but are not able to look into the software and infrastructure that provides those services. In this technical report, we summarize our results of four activities to realize a complete tooling around Kieker, Palladio, and MAMBA, supporting performance and cost prediction, and the evaluation of data privacy in context of geo-locations. Furthermore, the report illustrates our efforts to extend Palladio

Run-time Architecture Models for Dynamic Adaptation and Evolution of Cloud Applications

Cloud applications are subject to continuous change due to modifications of the software application itself and, in particular, its environment. To manage changes, cloud-based systems provide diverse self-adaptation mechanisms based on run-time models. Observed run-time models are means for leveraging self- adaption, however, are hard to apply during software evolution as they are usually too detailed for comprehension by humans.In this paper, we propose iObserve, an approach to cloud-based system adaptation and evolution through run-time observation and continuous quality analysis. With iObserve, run-time adaptation and evolution are two mutual, interwoven activities that influence each other. Central to iObserve is (a) the specification of the correspondence between observation results and design models, and (b) their use in both adaptation and evolution. Run-time observation data is promoted to meaningful values mapped to design models, thereby continuously updating and calibrating those design models during run-time while keeping the models comprehendible by humans. This engineering approach allows for automated adaptation at run-time and simultaneously supports software evolution. Model-driven software engineering is employed for various purposes such as monitoring instrumentation and model transformation. We report on the experimental evaluation of this approach in lab experiments using the CoCoME benchmark deployed on an OpenStack cloud

Light emission intensities of luminescent Y2O3:Eu and Gd2O3:Eu particles of various sizes

There is great technological interest in elucidating the effect of particle size on the luminescence efficiency of doped rare earth oxides. This study demonstrates unambiguously that there is a size effect and that it is not dependent on the calcination temperature. The Y2O3:Eu and Gd2O3:Eu particles used in this study were synthesized using wet chemistry to produce particles ranging in size between 7 nm and 326 nm and a commercially available phosphor. These particles were characterized using three excitation methods: UV light at 250 nm wavelength, electron beam at 10 kV, and X-rays generated at 100 kV. Regardless of the excitation source, it was found that with increasing particle diameter there is an increase in emitted light. Furthermore, dense particles emit more light than porous particles. These results can be explained by considering the larger surface area to volume ratio of the smallest particles and increased internal surface area of the pores found in the large particles. For the small particles, the additional surface area hosts adsorbates that lead to non-radiative recombination, and in the porous particles, the pore walls can quench fluorescence. This trend is valid across calcination temperatures and is evident when comparing particles from the same calcination temperature

Validierungsverfahren von EMV-Messplätzen im Frequenzbereich von 18 – 40 GHz

In den vergangenen Jahren wurden Validierungsverfahren für EMV-Messplätze in den Frequenzbereichen 1 – 18 GHz und 9 kHz – 30 MHz entwickelt [1,2]. Das Validierungsverfahren unterhalb von 30 MHz befindet sich im Stadium des positiv abgestimmten CDV und der FDIS ist in Vorbereitung. Da Frequenzbereiche weit oberhalb 1 GHz bereits in Benutzung sind und sich 5G im Frequenzbereich 2 (FR2) oberhalb 24 GHz mindestens in der Erprobungsphase befindet, ist es dringend geboten, auch für den Bereich oberhalb 18 GHz Validierungsverfahren für EMV-Messplätze zu etablieren. Auf der letzten CISPR Präsenz Sitzung 2019 in Shanghai wurde dazu eine Arbeitsgruppe gebildet. Das Ziel ist es, ein Validierungsverfahren für EMV Messplätze im Frequenzbereich von 18 – 40 GHz auszuarbeiten. Dafür werden bekannte und eingeführte Verfahren wie das Site-VSWR, die NSA-Volumenmethode als auch Zeitbereichsmethoden untersucht, um das am besten geeignete Verfahren auszuwählen. Dieser Artikel beschäftigt sich mit einem Vergleich des TD SVSWR Verfahrens nach ANSI C63.25.1 [1] mit dem SVSWR Verfahren nach CISPR 16-1-4 [2]. Zunächst werden Messungen im Frequenzbereich von 1 – 18 GHz vorgestellt und verglichen. Danach werden Einflussfaktoren aufgezeigt, die bei dem Validierungsverfahren berücksichtigt werden müssen

Interrelation between the isoscalar octupole phonon and the proton-neutron mixed-symmetry quadrupole phonon in near spherical nuclei

The interrelation between the octupole phonon and the low-lying proton-neutron mixed-symmetry quadrupole phonon in near-spherical nuclei is investigated. The one-phonon states decay by collective E3 and E2 transitions to the ground state and by relatively strong E1 and M1 transitions to the isoscalar 2+ state. We apply the proton-neutron version of the Interacting Boson Model including quadrupole and octupole bosons (sdf-IBM-2). Two F-spin symmetric dynamical symmetry limits of the model, namely the vibrational and the \gamma-unstable ones, are considered. We derive analytical formulae for excitation energies as well as B(E1), B(M1), B(E2) and B(E3) values for a number of transitions between low-lying states.Comment: 25 pages, 3 figures, LaTeX, epsfig. Nucl. Phys. A (in press

Concentration of electric dipole strength below the neutron separation energy in N = 82 nuclei

The semi-magic nuclei Ba-138, Ce-140, and Sm-144 have been investigated in photon scattering experiments up to an excitation energy of about 10 MeV. The distribution of the electric dipole strength shows a resonance like structure at energies between 5.5 and 8 MeV exhausting up to 1% of the isovector E1 Energy Weighted Sum Rule.Comment: 10 pages, 3 figure

Search for the electric dipole excitations to the 3s1/2⊗[21+⊗31−]3s_{1/2} \otimes [2^{+}_{1} \otimes 3^{-}_{1}] multiplet in 117^{117}Sn

The odd-mass $^{117}$Sn nucleus was investigated in nuclear resonance fluorescence experiments up to an endpoint energy of the incident photon spectrum of 4.1 MeV at the bremsstrahlung facility of the Stuttgart University. More than 50 mainly hitherto unknown levels were found. From the measurement of the scattering cross sections model independent absolute electric dipole excitation strengths were extracted. The measured angular distributions suggested the spins of 11 excited levels. Quasi-particle phonon model calculations including a complete configuration space were performed for the first time for a heavy odd-mass spherical nucleus. These calculations give a clear insight in the fragmentation and distribution of the $E1$, $M1$, and $E2$ excitation strength in the low energy region. It is proven that the $1^{-}$ component of the two-phonon $[2^{+}_{1} \otimes 3^{-}_{1}]$ quintuplet built on top of the $1/2^{+}$ ground state is strongly fragmented. The theoretical calculations are consistent with the experimental data.Comment: 10 pages, 5 figure

Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe