Alfonso Urquia

This manuscript presents a data descriptor for a comprehensive lithium-ion battery dataset designed to support the development of rapid diagnostic protocols for estimating cell capacity. The dataset includes controlled aging experiments and extensive multimodal characterization of Samsung INR21700-50E lithium-ion cells. A total of 160 brand-new cells were aged under designed charge and discharge strategies at room temperature to generate a representative distribution of capacity values. Throughout the aging process, time-resolved voltage and current measurements were recorded, along with derived quantities such as power, charge, and energy. Capacity measurements were performed both prior to and following aging. After aging, the cells underwent further characterization using various diagnostic techniques, including a galvanostatic low-rate (C/48) cycle, static and dynamic electrochemical impedance spectroscopy, electrochemical noise analysis, and short- and long-term current interruption tests.

The Argia optical simulator facilitates to describing nano-textured silicon surfaces with highly irregular reliefs intended for solar cell applications, and to analyze their reflectance and transmittance using the rigorous coupled wave analysis (RCWA) method. Argia was programmed using MATLAB’s object-oriented programming features. This makes the code easier to understand and provides an elegant syntax for defining nano-textured surfaces, materials, and illumination conditions. The discussion covers Argia’s object-oriented design, the implementation of the RCWA method, and Argia’s use. The latter is demonstrated through the modeling and simulation of one 0.5-square-micron silicon sample nano-textured with randomly distributed pyramids, and two 0.5-square-micron black silicon samples.

Black silicon is relevant for the photovoltaic industry when searching for low-reflectance, low-defect front surface, which is the goal of this work. We have fabricated samples using reactive ion etching (RIE) plus chemical etching for the smoothing, characterized them, and built modeling tools capable of reproducing the resulting geometric features, based on the process parameters. Reflectance is simulated using a proprietary rigorous coupled wave analysis (RCWA)-based tool, and compared with the experimental results. A good matching was achieved using a simple unit cell, and a better agreement when using a 0.5 square microns sample. Finally, an optimum trade-off between low reflectance and low thickness has been achieved.

A microsimulation model of traffic described using the Modelica language in combination with the Modelica libraries developed by the authors, ABMLib and CellularAutomataLib2, is presented. Modelica facilitates the description of equation-based models using the physical modeling paradigm, and its combination with the discrete-event and agent-based modeling functionality of the developed libraries constitutes a powerful and versatile tool. The functionality of ABMLib is extended to facilitate the description of individual agent behavior as a combination of equation-based and discrete-event models. In this way, vehicle dynamics and fuel consumption are modeled using equations, while driver behavior is described using an agent-based model. Vehicles move along the road, which is described as a combination of interconnected segments that constitute the environment for the agents. A cellular automaton is used to model the CO2 emissions of vehicles to the environment. A model that represents two consecutive road segments with a semaphore between them is used to illustrate the provided functionality.

Virtual labs are valuable educational resources in control education, and are widely used in the process industry as tools for operator training and decision aid. In these application domains, virtual labs typically rely on the interactive simulation of large-scale hybrid-DAE models with components of different engineering domains, whose description can be greatly simplified by the use of the Modelica language. Existing free and commercial Modelica libraries of different domains can be used to describe these models. The Interactive Modelica library facilitates developing virtual labs based on Modelica models, using only Modelica. A new major release of the Interactive Modelica library is presented in this paper, whose most relevant feature is to facilitate the implementation of collaborative virtual labs written using only the Modelica language. This library can be used with the environment OpenModelica, facilitating the implementation of cooperative virtual labs using only open software. This type of virtual lab, which allows several students to interact cooperatively with the same model simulation run, is an effective tool in the context of collaborative learning methods. The efficient communication among the graphical user interfaces and the simulation model is a key issue. We developed a new communication protocol, a synchronization algorithm, and redesigned the Modelica classes of the library to make the communication completely transparent to virtual lab developers. The implementation of a collaborative virtual lab for process control education, based on a simplified version of the Tennessee Eastman process, is discussed. The Interactive Modelica library is freely distributed under Modelica License 2 and can be downloaded from http://www.euclides.dia.uned.es/Interactive

With the continuous improvement in Computer Modelling and Simulation Environment (CMSE) applications being made, computer modelling and simulation (CMS) is proven a better alternative as opposed to conventional physical modelling. The advancement of computing hardware allows accurate results to be obtained faster, safer and at a fraction of its original cost. Despite the proven advantages, CMSE adoption among companies may be fairly new in Malaysia. This study is aimed at quantifying the demand of CMSE specialists in Malaysia as well as gaining insights in the companies’ requirements of specialists’ knowledge, competencies and skills. Thus, a survey, consisted of 3 main parts, was conducted among industries in Malaysia as a tool of measurement of the demand. The survey included questions related to the general information of the organization, specialists’ competencies relation to the job scope, and finally the professional and educational standards among specialists. In general, it was found that practically-competent specialists in CMSE are in high demand among engineering companies. Furthermore, professional courses through distance learning would be of high interest among companies to send their employees to gain practical competency in CMSE.

An important consideration in higher education is that graduates meet or exceed the program outcomes (POs). While there exists anecdotal evidence that the use of modern tools i.e. computer modelling and simulation, improve attainment of these outcomes, there is little empirical research available. Where empirical evidence is available, the variables considered would almost certainly have a bearing on the outcomes. In this work, the attainment of the POs by undergraduate engineering students in courses with and without the use of modern tools, based on quantitative data, were compared. It was hypothesized that courses using modern tools would lead to better overall attainment of POs, compared to courses not using these tools. As a case study, the PO attainment of students in the Mechanical Engineering undergraduate program at Universiti Teknologi PETRONAS (UTP) was considered. Quantitative data obtained through UTP's outcomebased education (OBE) software was used to assess the overall attainment of the POs for all courses for a cohort of 126 Mechanical Engineering undergraduate students class of 2017. It was found that, for the case study considered, the usage of modern tools has led to slightly better attainment of some POs, with slightly poorer attainment in other POs. Specifically, attainment in POs where the cognitive or the knowledge domain is more dominant improved, as the usage of modern tools helped students to understand theoretical concepts better. Attainment in POs were the affective domain is more dominant recorded a slight decrease, and the incorporation of modern tools did not aid in the attainment of these POs. The study is at a preliminary stage and a more detailed study, involving more cohorts, is planned to establish a correlation (if any) between the use of modern tools in higher education and attainment of POs.