Evaluation of the Degree of Rate Control via Automatic Differentiation

The degree of rate control quantitatively identifies the kinetically relevant (sometimes known as rate-limiting) steps of a complex reaction network. This concept relies on derivatives which are commonly implemented numerically, e.g. with finite differences. Numerical derivatives are tedious to implement, and can be problematic, and unstable or unreliable. In this work, we demonstrate the use of automatic differentiation in the evaluation of the degree of rate control. Automatic differentiation libraries are increasingly available through modern machine learning frameworks. Compared to the finite differences, automatic differentiation provides solutions with higher accuracy with lower computational cost. Furthermore, we illustrate a hybrid local-global sensitivity analysis method, the distributed evaluation of local sensitivity analysis (DELSA), to assess the importance of kinetic parameters over an uncertain space. This method also benefits from automatic differentiation to obtain high-quality results efficiently.

Exploring parent and student engagement in school self-evaluation in four European countries

The purpose of this paper, which is part of a three-year EU Erasmus+-funded study titled ‘Distributed Evaluation and Planning in Schools’ (DEAPS), is to provide an analysis of policies, structures, processes, supports and barriers that exist to enable or inhibit the involvement of students and parents in school evaluation in four European countries (Belgium, Ireland, Portugal and Turkey). Document analysis was used for this study and some 348 peer-reviewed articles, and 28 national and transnational policy documents were included in the analysis. Based on this review it would be reasonable to suggest that the student/parent voice agenda around evaluation in schools remains, by and large, aspirational. It is extolled in policy but in practice is mainly tokenistic with very little evidence of impact on the work of schools. In light of this, it is argued that government and school-level policies and strategies need to be reconsidered to enhance students’ and parents’ engagement in school evaluation. As a first step, significant further empirical research on the limitations on and conditions necessary for stakeholder voice in education is required.

Solving School’s Survey Request Overload

Limited information is available on strategies for managing the large number of survey requests that reach an individual nursing school. This article addresses problems identified in managing survey requests and describes the implementation and evaluation of a solution. Identified problems included the appearance of endorsing studies of varying quality and rigor, overlap and competition between external study requests and internal studies, respondent burden, and level of anonymity and confidentiality. The solution included a school-wide policy for tracking and vetting study requests before they were distributed. Evaluation data show the number of requests received (total, by month and source, by target population), their disposition (withdrawn, approved, not approved for distribution), and quality improvement data on meeting a 30-day target turnaround time. Additional considerations are also discussed.

Sensitivity and identifiability of rheological parameters in debris flow modeling

Over the past decades, several numerical models have been developed to understand, simulate and predict debris flow events. Typically, these models simplify the complex interactions between water and solids using a single-phase approach and different rheological models to represent flow resistance. In this study, we perform a sensitivity analysis on the parameters of a debris flow numerical model (FLO-2D) for a suite of relevant variables (i.e., maximum flood area, maximum flow velocity, maximum height and deposit volume). Our aims are to (i) examine the degree of model overparameterization and (ii) assess the effectiveness of observational constraints to improve parameter identifiability. We use the Distributed Evaluation of Local Sensitivity Analysis (DELSA) method, which is a hybrid local–global technique. Specifically, we analyze two creeks in northern Chile (∼29∘ S, 70∘ W) that were affected by debris flows on 25 March 2015. Our results show that SD (surface detention) and β1 (a parameter related to viscosity) provide the largest sensitivities. Further, our results demonstrate that equifinality is present in FLO-2D and that the final deposited volume and maximum flood area contain considerable information to identify model parameters.

Sensitivity and identifiability of rheological parameters in debris flow modeling

Over the past decades, several numerical models have been developed to understand, simulate and predict debris flow events. Typically, these models simplify the complex interactions between water and solids using a single-phase approach and different rheological models to represent flow resistance. In this study, we perform a sensitivity analysis on the parameters of a debris flow numerical model (FLO-2D) for a suite of relevant variables (i.e., maximum flood area, maximum flow velocity, maximum flow velocity, deposit volume). Our aims are to (i) examine the degree of model overparameterization, and (ii) assess the effectiveness of observational constraints to improve parameter identifiability. We use the Distributed Evaluation of Local Sensitivity Analysis (DELSA) method, which is a hybrid local-global technique. Specifically, we analyze two creeks in northern Chile that were affected by debris flows on March 25, 2015. Our results show that SD and β1 – a parameter related to viscosity – provide the largest sensitivities. Further, our results demonstrate that equifinality is present in FLO-2D, and that final deposited volume and maximum flood area contain considerable information to identify model parameters.