Beam Dynamics in High Intensity Cyclotrons Including Neighboring Bunch Effects: Model, Implementation and Application

Space charge effects, being one of the most significant collective effects, play an important role in high intensity cyclotrons. However, for cyclotrons with small turn separation, other existing effects are of equal importance. Interactions of radially neighboring bunches are also present, but their combined effects has not yet been investigated in any great detail. In this paper, a new particle in cell based self-consistent numerical simulation model is presented for the first time. The model covers neighboring bunch effects and is implemented in the three-dimensional object-oriented parallel code OPAL-cycl, a flavor of the OPAL framework. We discuss this model together with its implementation and validation. Simulation results are presented from the PSI 590 MeV Ring Cyclotron in the context of the ongoing high intensity upgrade program, which aims to provide a beam power of 1.8 MW (CW) at the target destination

Event-based quickflow simulation with OpenLISEM in a burned Mediterranean forest catchment

Recently burnt areas typically reveal strong to extreme hydrological responses, as a consequence of loss of protective soil cover and heating-induced changes in topsoil properties. Soil water repellency (SWR) has frequently been referred to as one of the explanatory variables for fireenhanced surface runoff generation but this has been poorly demonstrated, especially at the catchment scale. This study employs a process-based modelling approach to better understand the relevance of SWR in the hydrological response of a small, entirely burnt catchment in central Portugal, in particular by comparing hydrological events under contrasting initial conditions of dry vs wet soils. The OpenLISEM model was applied to a selection of 16 major rainfall runoff events that occurred during the first 2 post-fire years. The automatic calibration procedure resulted in good model performance, but it worsened for validation events. Furthermore, uncertainty analysis revealed an elevated sensitivity of OpenLISEM to event-specific conditions, especially for predicting the events’ total and peak flows. Also, predicted spatial patterns in runoff poorly agreed with the runoff observed in microplots. Model performance improved when events were separated by dry and wet initial moisture conditions, particularly for wet conditions, suggesting the role of variables other than initial soil moisture.info:eu-repo/semantics/publishedVersio

Transparency or Stimulating Meaningfulness and Self-Regulation? A Case Study About a Programmatic Approach to Transparency of Assessment Criteria

This exploratory case study focused on fostering meaning making of assessment criteria and standards at the module level and the course/programme level (the entire study plan), and the role of self-regulation in this meaning making process. The research questions that guided this study are: (1) How can students' meaning making of assessment criteria at the module level be fostered, (2) How can students' meaning making of assessment criteria at the programme level be fostered, and (3) How can self-regulation contribute to students' meaning making process? We explored the design and implementation of a rather new Master's programme in The Netherlands: The Master's Expert Teacher of Vocational Education (METVE). Interviews with three developers, three teachers, and 10 students of the METVE were analyzed. For each research question, several themes were derived from the data. Results indicate that meaning making takes place at the module level by using holistic assessment criteria and evaluative experiences, which allow students to make choices within the boundaries set by the assessment criteria. Meaning making at the programme level is experienced as much more difficult by students as well as teachers. The design of the METVE programme fosters meaning making at the programme level, but METVE teachers also express difficulties supporting this. Finally, we found that students perceive self-regulation as something extra for which they don't have enough time. Self-regulation at the programme level was not explicitly addressed and supported in the METVE, which makes it more difficult for some students to steer their learning process toward the role they are aiming for in professional practice after completing the Master's programme

Епідигматичний модус англійських числівників

У статті розглядаються англійські числівники, денумеративи та їх епідигматичний модус. Семантична структура порівнюваних груп розглядаються на векторах їх походження та модифікації. Частиномовна представленість досліджується на просторах їх граматичного, семантичного і словотворчого буття. Визначаються перспективи подальшого дослідження. При цитуванні документа, використовуйте посилання http://essuir.sumdu.edu.ua/handle/123456789/30551В статье исследуются английские числительные, денумеративы, а также их эпидигматичекие аспекты. Семантическая структура сравниваемых единиц изучается на векторах семантики, грамматики и словотворчества. Намечаются перспективы дальнейшего исследования. При цитировании документа, используйте ссылку http://essuir.sumdu.edu.ua/handle/123456789/30551The article in question deals with the English numerals, denumerals and their epidigmatic tendencies. The semantic structures of both groups are being focused upon. The words under analysis are viewed in terms of their initial and secondary grounds. The item of part of speech charge is being considered in terms of grammatical, semantic and epidigmatic aspects. Thus, the modus of the paradigmatic groups have been considered wide perspectives for further investigation. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3055

Assessment and feedback in higher education reimagined: using programmatic assessment to transform higher education

We argue that assessment and feedback practices in higher education need to be transformed to better address three purposes: promoting learning, assuring assessment rigour, and communicating students’ employability. To address shortcomings in the current assessment and feedback culture, we propose programmatic assessment (PA), a new approach to assessment developed initially in medical education and now applied to a range of other professional fields. We outline eight recommendations that synthesise the key principles underpinning PA. Then, drawing on experience with PA in various professional fields in the Netherlands, we describe and illustrate four action steps for programme teams to take to implement programmatic assessment. We highlight implications of such a shift for leaders and professional services staff before concluding that PA can transform higher education by creating a more productive culture of assessment and feedback

Two decades of numerical modelling to understand long term fluvial archives: Advances and future perspectives

The development and application of numerical models to investigate fluvial sedimentary archives has increased during the last decades resulting in a sustained growth in the number of scientific publications with keywords, 'fluvial models', 'fluvial process models' and 'fluvial numerical models'. In this context we compile and review the current contributions of numerical modelling to the understanding of fluvial archives. In particular, recent advances, current limitations, previous unexpected results and future perspectives are all discussed. Numerical modelling efforts have demonstrated that fluvial systems can display non-linear behaviour with often unexpected dynamics causing significant delay, amplification, attenuation or blurring of externally controlled signals in their simulated record. Numerical simulations have also demonstrated that fluvial records can be generated by intrinsic dynamics without any change in external controls. Many other model applications demonstrate that fluvial archives, specifically of large fluvial systems, can be convincingly simulated as a function of the interplay of (palaeo) landscape properties and extrinsic climate, base level and crustal controls. All discussed models can, after some calibration, produce believable matches with real world systems suggesting that equifinality - where a given end state can be reached through many different pathways starting from different initial conditions and physical assumptions - plays an important role in fluvial records and their modelling. The overall future challenge lies in the development of new methodologies for a more independent validation of system dynamics and research strategies that allow the separation of intrinsic and extrinsic record signals using combined fieldwork and modelling

Two-neutron transfer reaction mechanisms in 12^{12}C(6^6He,4^{4}He)14^{14}C using a realistic three-body 6^{6}He model

The reaction mechanisms of the two-neutron transfer reaction $^{12}$C($^6$He,$^4$He) have been studied at 30 MeV at the TRIUMF ISAC-II facility using the SHARC charged-particle detector array. Optical potential parameters have been extracted from the analysis of the elastic scattering angular distribution. The new potential has been applied to the study of the transfer angular distribution to the 2$^+_2$ 8.32 MeV state in $^{14}$C, using a realistic 3-body $^6$He model and advanced shell model calculations for the carbon structure, allowing to calculate the relative contributions of the simultaneous and sequential two-neutron transfer. The reaction model provides a good description of the 30 MeV data set and shows that the simultaneous process is the dominant transfer mechanism. Sensitivity tests of optical potential parameters show that the final results can be considerably affected by the choice of optical potentials. A reanalysis of data measured previously at 18 MeV however, is not as well described by the same reaction model, suggesting that one needs to include higher order effects in the reaction mechanism.Comment: 9 pages, 9 figure

An improved method for calculating slope length (λ) and the LS parameters of the Revised Universal Soil Loss Equation for large watersheds

The Universal Soil Loss Equation (USLE) and its revised version (RUSLE) are often used to estimate soil erosion at regional landscape scales. USLE/RUSLE contain parameters for slope length factor (L) and slope steepness factor (S), usually combined as LS. However a major limitation is the difficulty in extracting the LS factor. Methods to estimate LS based on geographic information systems have been developed in the last two decades. L can be calculated for large watersheds using the unit contributing area (UCA) or the slope length (λ) as input parameters. Due to the absence of an estimation of slope length, the UCA method is insufficiently accurate. Improvement of the spatial accuracy of slope length and LS factor is still necessary for estimating soil erosion. The purpose of this study was to develop an improved method to estimate the slope length and LS factor. We combined the algorithm for multiple-flow direction (MFD) used in the UCA method with the LS-TOOL (LS-TOOLSFD) algorithms, taking into account the calculation errors and cutoff conditions for distance, to obtain slope length (λ) and the LS factor. The new method, LS-TOOLMFD, was applied and validated in a catchment with complexly variable slopes. The slope length and LS calculated by LS-TOOLMFD both agreed better with field data than with the calculations using the LS-TOOLSFD and UCA methods, respectively. We then integrated the LS-TOOLMFD algorithm into LS-TOOL developed in Microsoft's.NET environment using C# with a user-friendly interface. The method can automatically calculate slope length, slope steepness, L, S, and LS factor, providing the results as ASCII files that can be easily used in GIS software and erosion models. This study is an important step forward in conducting accurate large-scale erosion evaluation