347 research outputs found

    Evaporation Channel as a Tool to Study Fission Dynamics

    Full text link
    The dynamics of the fission process is expected to affect the evaporation residue cross section because of the fission hindrance due to the nuclear viscosity. Systems of intermediate fissility constitute a suitable environment for testing such hypothesis, since they are characterized by evaporation residue cross sections comparable or larger than the fission ones. Observables related to emitted charged particle, due to their relatively high emission probability, can be used to put stringent constraints on models describing the excited nucleus decay and to recognize the effects of fission dynamics. In this work model simulations are compared with the experimental data collected via the ^{32}S + ^{100}Mo reaction at E_{lab}= 200 MeV. By comparing an extended set of evaporation channel observables the limits of the statistical model and the large improvement coming by using a dynamical model are evidenced. The importance of using a large angular covering apparatus to extract the observable is stressed. The opportunity to measure more sensitive observables by a new detection device in operation at LNL are also discussed.Comment: v1: 7 pages, 6 figure

    Towards Quality-Aware Development of Big Data Applications with DICE

    No full text
    © Springer International Publishing Switzerland 2016.Model-driven engineering (MDE) has been extended in recent years to account for reliability and performance requirements since the early design stages of an application. While this quality-aware MDE exists for both enterprise and cloud applications, it does not exist yet for Big Data systems. DICE is a novel Horizon2020 project that aims at filling this gap by defining the first quality-driven MDE methodology for Big Data applications. Concrete outputs of the project will include a data-aware UML profile capable of describing Big Data technologies and architecture styles, data-aware quality prediction methods, and continuous delivery tools

    Guiding the Service Engineering Process: the Importance of Service Aspects

    Get PDF

    A UML Profile for the Design, Quality Assessment and Deployment of Data-intensive Applications

    Get PDF
    Big Data or Data-Intensive applications (DIAs) seek to mine, manipulate, extract or otherwise exploit the potential intelligence hidden behind Big Data. However, several practitioner surveys remark that DIAs potential is still untapped because of very difficult and costly design, quality assessment and continuous refinement. To address the above shortcoming, we propose the use of a UML domain-specific modeling language or profile specifically tailored to support the design, assessment and continuous deployment of DIAs. This article illustrates our DIA-specific profile and outlines its usage in the context of DIA performance engineering and deployment. For DIA performance engineering, we rely on the Apache Hadoop technology, while for DIA deployment, we leverage the TOSCA language. We conclude that the proposed profile offers a powerful language for data-intensive software and systems modeling, quality evaluation and automated deployment of DIAs on private or public clouds

    A constraint-based approach to quality assurance in service choreographies.

    Get PDF
    Knowledge about the quality characteristics (QoS) of service com- positions is crucial for determining their usability and economic value. Ser- vice quality is usually regulated using Service Level Agreements (SLA). While end-to-end SLAs are well suited for request-reply interactions, more complex, decentralized, multiparticipant compositions (service choreographies) typ- ically involve multiple message exchanges between stateful parties and the corresponding SLAs thus encompass several cooperating parties with interde- pendent QoS. The usual approaches to determining QoS ranges structurally (which are by construction easily composable) are not applicable in this sce- nario. Additionally, the intervening SLAs may depend on the exchanged data. We present an approach to data-aware QoS assurance in choreographies through the automatic derivation of composable QoS models from partici- pant descriptions. Such models are based on a message typing system with size constraints and are derived using abstract interpretation. The models ob- tained have multiple uses including run-time prediction, adaptive participant selection, or design-time compliance checking. We also present an experimen- tal evaluation and discuss the benefits of the proposed approach

    How to improve educational behaviors for caregivers and patients having Central Venous Access Device (CVAD). a scoping review

    Get PDF
    Objective: Central venous access devices (CVADs) are essential to the modern management of patients with hematological malignancies and solid tumors. Educational programs play a crucial role in promoting appropriate patient actions to support patient safety during hospitalization and homecare. This review aimed to identify literature concerning educational interventions to promote patients’ actions to overcome CVAD-related problems and improve self-monitoring and self-management. Materials and Methods: Documentary evaluation of international databases, such as PubMed, CINAHL, Scopus and Cochrane. Searching for data on population, context and concept regarding CVAD self-management. The extracted data was subject to thematic analysis. The following scoping reviews were developed using the five-stage framework outlined by Arksey and O’Malley, and advanced by Levac and colleagues. Results: Of the 2802 articles identified, 19 research articles were selected in this review. Educational programs have been shown to improve CVAD self management, to decrease stress and anxiety related to their use, and to reduce the onset of complications. In addition, nurses have proven to be the professional reference figure for educational interventions. Conclusions: The results of the study lead to the conclusion that programs aimed at improving selfcare and reducing the onset of complications in patients living with chronic and debilitating diseases should be made available to a larger portion of individuals. Both generic and specific programs are needed, in the different contexts of home and hospital, for the short and long term, in order to ameliorate participants’ abilities. The results of this study should, therefore, encourage health professionals to plan, carry out, and evaluate the establishment of educational programs with patient participation

    Fission Dynamics: The Quest of a Temperature Dependent Nuclear Viscosity

    Get PDF
    oai:ojs2.jnp.chitkara.edu.in:article/2This paper presents a journey within some open questions about the current use of a temperature dependent nuclear viscosity in models of nuclear fission and proposes an alternative experimental approach by using systems of intermediate fissility. This study is particularly relevant because: i) systems of intermediate fissility offer a suitable frame-work since the intervals between the compound nucleus and scission point temperatures with increasing excitation energy are much smaller than in the case of heavier systems, ii) the dependence of viscosity on the temperature may change with the fissility of the composite system; iii) the opportunity to measure also observables in the evaporation residues channel translates into a larger set of effective constraints for the models

    Clustering effects in 48Cr composite nuclei produced via 24Mg + 24Mg reaction

    Get PDF
    In the framework of studying clustering effects in N=Z light nuclei, an experiment was carried out to get information on the properties of the 48 Cr composite nuclei produced via the 24 Mg +24 Mg reaction. In particular, the study regards the 48 Cr at 60 MeV of excitation energy where a resonance with a narrow width (170 KeV) has been found by measuring the elastic and anelastic channels. To determine the deformation of this state, evaporative Light Charged Particles (LCP) are measured and compared to the Statistical Model (SM) predictions, which are very sensitive to nuclear deformation. The experiment was performed at LNL using the 8ĒLP apparatus to select LCPs and a Parallel Plate Avalanche Counter (PPAC) system to detect the Evaporation Residues (ER). Preliminary results on the measurements of ER – LCP and LCP – LCP angular correlations are presented which indicate the presence of a very large deformation.The analysis will proceed with the extraction of the LCP energy spectra and with the angular correlations for high multiplicity channels to determine the deformation
    • …
    corecore