Interactive Computer Aided Design of Electrochemical Systems

The most popular and widely used rechargeable battery numerical model, the dualfoil, was developed in fortran by John Newman and coworkers1-3, and enables the user to describe the time-dependent electrochemical transport of lithium and charge, through the application of concentrated solution theory in porous media. Such a model has enabled the design of many advanced lithium-ion batteries for hybrid and plug-in electric vehicles that can operate under high current densities. Historically, however, the dualfoil and other subsequently derived models are cumbersome and unwieldy when used, and offer limited flexibility regarding parameter variability, integration into more sophisticated numerical descriptions, coupling to multiscale formulations, or the simple visualization of generated data. The nature of dualfoil makes it difficult to use, and it does not allow for systematic parametric analyses, or direct integration into high performing, multiscale numerical frameworks. This work introduces a proof of concept for a flexible application programming interface, dualfoil.py, that enables hierarchical control over the dualfoil legacy code and visualization modules, and provides the user with the ability to rapidly set up complex, multiscale simulations. Furthermore, the program features a GUI-mode for single-run simulations, and a powerful text-mode for setting up large simulation queues. By making use of the object oriented nature of Python, dualfoil.py allows the user to generate, organize, and visualize the electrochemical responses from the battery. Cell potential, anode and cathode active material utilization, and power/energy densities of multiple battery scenarios are modeled and presented, demonstrating the iterative capability of dualfoil.py. This versatile program allows for users of any skill level to achieve robust results in a control oriented and rapidly deployable manner

English as a Language for Teaching and Learning

Exam paper for exam paper second semester English as a Language for Teaching and Learnin

A Computational Comparison of Optimization Methods for the Golomb Ruler Problem

The Golomb ruler problem is defined as follows: Given a positive integer n, locate n marks on a ruler such that the distance between any two distinct pair of marks are different from each other and the total length of the ruler is minimized. The Golomb ruler problem has applications in information theory, astronomy and communications, and it can be seen as a challenge for combinatorial optimization algorithms. Although constructing high quality rulers is well-studied, proving optimality is a far more challenging task. In this paper, we provide a computational comparison of different optimization paradigms, each using a different model (linear integer, constraint programming and quadratic integer) to certify that a given Golomb ruler is optimal. We propose several enhancements to improve the computational performance of each method by exploring bound tightening, valid inequalities, cutting planes and branching strategies. We conclude that a certain quadratic integer programming model solved through a Benders decomposition and strengthened by two types of valid inequalities performs the best in terms of solution time for small-sized Golomb ruler problem instances. On the other hand, a constraint programming model improved by range reduction and a particular branching strategy could have more potential to solve larger size instances due to its promising parallelization features

Tracking neuronal motility in live murine retinal explants

The developing retina undergoes dynamic organizational changes involving significant intra-retinal motility of the encompassing cells. Here, we present a protocol for tracking retinal cell motility in live explanted mouse retinae. Although originally applied to rod and cone photoreceptors, this strategy is applicable to any fluorescently labeled cell in mouse retinae and other similar experimental retinal models. Careful tissue handling is critical for the successful acquisition of high-quality live imaging data. Further instructions for semi-automated in silico data handling are provided. For complete details on the use and execution of this protocol, please refer to Aghaizu et al. (2021)

Bonolo: A General Digital Library System for File-based Collections

There is an ever-increasing amount of digital content being generated that needs to be well-organised, preserved and made accessible. The majority of generic repository software tools that currently exist are, arguably, overly complex, thus making collections dicult to manage and maintain in resource constrained environments. A possible solution to this problem would, in part, require designing digital library tools and services that are simple and easy to manage. This paper describes a digital library system that is based on a set of design decisions aimed at simplifying repository software architectures. The proposed system makes use of a hierarchical file-store for storage of digital objects. Evaluation of the system by means of a user experience study was conducted to investigate the usefulness of the system, its relative ease of use and what effect, if any, the architecture would have on the user experience. Experimental results showed that users found the system useful, effective and easy to use and that the architecture did not appear to negatively in uence the user experience

Novel dynamic modelling of parallel HVAC/HVDC

Belgium Herbarium image of Meise Botanic Garden

Novel dynamic modelling of parallel HVAC/HVDC

A novel approach is presented for eficiently modeling a power system which incIudes parallel-connected HVAC, andHVDC transmission systems. The proposed model has been derived for a system in which an AC generator is connected toan infinite bus system through a parallel AC tie line and a HVDC link. In addition to state-space representation, a blockdiagram representation has been formed to analyze system stability. In this new block diagram representation, the dynamiccharacteristics of the system are expressed in terms of a newly developed H constant. The development of the blockdiagram and associated H constants are explained. The new model is evaluated using PSCADiRTDS real time digitalsimulation