Peter L. Bishay

Analysis of Elastic Media with Voids Using a Mixed-Collocation Finite-Element Method

AbstractIn this paper, a recently developed type of lower-order mixed finite elements is extended to model porous materials based on the microdilatation theory. These mixed finite elements are base...

FEApps: Boosting students' enthusiasm for coding and app designing, with a deeper learning experience in engineering fundamentals

In this article, a model for a multi‐goal course project is reported and discussed. Teams of students are asked to create attractive Matlab Apps for topics related to “Fundamentals of Engineering” (FE) exam (hence called “FEApps”). The main goals of this project, discussed in details in the article, are: (1) allowing students practice coding in a new innovative environment, (2) encouraging students to think as designers who create user‐friendly and robust products or services and their user manuals, (3) giving students the chance to work in teams with more useful interactions among teams, (4) showing students the benefit of writing multiple drafts for their projects and getting many feedback before the final presentations, and (5) refreshing students’ knowledge about topics related to FE exam. The article provides some examples of “FEApps” created by the participating students. This course project guarantees the highest student retention rates based on the well‐known “learning pyramid” and focuses on one of the relatively difficult mechanical engineering program outcomes, specified by the ABET, which is outcome i: “a recognition of the need for, and an ability to engage in life‐long learning.” The project assessment survey results proved that all project goals had been successfully met.

Introducing undergraduate research in Numerical Analysis of Engineering Systems course

Undergraduate research has a significant positive impact on the students’ educational experience but has many implementation challenges in curricular or co-curricular activities. This paper presents an approach for introducing undergraduate research to engineering students in a Numerical Analysis of Engineering Systems course, which is typically a junior-level undergraduate course in most engineering departments. A course project was designed to allow the participating students to work in teams, read an assigned research paper that presents an exact solution of a problem related to smart materials and structures, locate the main equations, and write a computer code that uses these equations to regenerate the published results. Each team of students gave a presentation on the assigned paper, the main equations, the code developed to regenerate the results and graphs, with interpretations and conclusions. The project is contributing to the course outcomes and learning objectives as well as multiple ABET student outcomes. Final survey showed the effectiveness of the proposed project in introducing students to undergraduate research, and giving them the chance to understand the technical and mathematical language used in research papers, and experience working on new challenging problems. The approach does not need involvement of multiple faculty members, or large funds and resources. The theme of the assigned research papers is dependent on the instructor’s field of research. The approach can be easily extended to other courses that teach computational methods and tools. The paper presents sample student projects and lessons learned in implementing the proposed approach.

Effect of Lattice Mismatch Strain Grading on the Electromechanical Behavior of Functionally Graded Quantum Dots

A fully coupled thermo-electro-mechanical models of cylindrical and truncated conical GaN/AlN Functionally Graded Quantum Dot (FGQD) systems with and without WL are analyzed in this study to determine the effect of lattice mismatch strain grading on the electromechanical behavior of the FGQD system. This has a technological and fundamental importance because the production methodology adopted for manufacturing QDs enables the composition of the QD material to be graded in the growth direction, so the material properties as well as the induced mismatch strain between the QD and the carrier matrix are accordingly graded. The power law is used to describe the grading function. Based on the obtained results, grading of material properties and lattice mismatch strain have significant effect on the distribution of the electromechanical quantities inside the QD and can be used as another tuning parameter in the design of QD systems.

Analysis and design of periodic beams for vibration attenuation

This paper presents a new finite-element-based design procedure for geometrically periodic beam structures to target a specific desired attenuation frequency band. Using the “forward approach,” the effects of the cell geometric parameters on the location of the stop bands are first studied. Then using the “reverse approach,” explicit expressions for the start and end frequencies of all stop bands are derived as functions of the cell geometric parameters using a symbolic solver. These expressions are used in the design procedure to determine the cell geometric parameters that will result in vibration attenuation in the desired attenuation band. The design procedure has been validated by comparison with the results of the forward approach in different problems targeting the first or second stop bands. It was found that, depending on the frequency range of the desired attenuation band, and the stop band selected to target the desired attenuation band in the design, one, two or no solution set for the cell geometric parameters can be obtained. For the case of two available solutions, the designer will have two design options that satisfy the design requirements to choose from.