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  1. The Electrical capacitance tomography (ECT) method has recently been adapted to obtain tomographic images of the cross section of a diesel particulate filter (DPF). However, a soot mass estimation algorithm is still needed to translate the ECT image pixel data to obtain soot load in the DPF. In this paper, we propose an estimation method to quantify the soot load in a DPF through an inverse algorithm that uses the ECT images commonly generated by a back-projection algorithm. The grayscale pixel data generated from ECT is used in a matrix equation to estimate the permittivity distribution of the cross section of the DPF. Since these permittivity data has direct correlation with the soot mass present inside the DPF, a permittivity to soot mass distribution relationship is established first. A numerical estimation algorithm is then developed to compute the soot mass accounting for the mass distribution across the cross-section of the DPF as well as the dimension of the DPF along the exhaust flow direction. Experimental data has been used to validate the proposed soot estimation algorithm which compared the estimated values with the actual measured soot mass. The estimated soot mass for various soot load amounts were found to correlate reasonably well with the measured soot masses in those cases. 
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  2. This work presents innovative origami optimization methods for the design of unit cells for complex origami tessellations that can be utilized for the design of deployable structures. The design method used to create origami tiles utilizes the principles of discrete topology optimization for ground structures applied to origami crease patterns. The initial design space shows all possible creases and is given the desired input and output forces. Taking into account foldability constraints derived from Maekawa's and Kawasaki's theorems, the algorithm designates creases as active or passive. Geometric constraints are defined from the target 3D object. The periodic reproduction of this unit cell allows us to create tessellations that are used in the creation of deployable shelters. Design requirements for structurally sound tessellations are discussed and used to evaluate the effectiveness of our results. Future work includes the applications of unit cells and tessellation design for origami inspired mechanisms. Special focus will be given to self-deployable structures, including shelters for natural disasters. 
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  3. Topology optimization is broadly recognized as a design approach to generate high-performance conceptual designs suitable for freeform fabrication, e.g., additive manufacturing. When other fabrication methods are considered, topology optimization must integrate manufacturing constraints. The integration of constraints for extrusion and casting has been addressed in the past by a few researcher groups. In this work, extrusion and casting constraints are revisited and extended to include plastic injection. The proposed method relies on the use of intersection planes and the definition of a parting line within the planes. The resulting topologies can be injected in a two-plate mold without the use of inserts. The implementation and results of the proposed approach are demonstrated in classic three-dimensional problems that include a cantilevered beam with different load conditions. 
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  4. Engineering educators have increasingly sought strategies for integrating the arts into their curricula. The primary objective of this integration varies, but one common objective is to improve students’ creative thinking skills. In this paper, we sought to quantify changes in student creativity that resulted from participation in a mechanical engineering course targeted at integrating engineering, technology, and the arts. The course was team taught by instructors from mechanical engineering and art. The art instructor introduced origami principles and techniques as a means for students to optimize engineering structures. Through a course project, engineering student teams interacted with art students to perform structural analysis on an origami-based art installation, which was the capstone project of the art instructor’s undergraduate origami course. Three engineering student teams extended this course project to collaborate with the art students in the final design and physical installation. 
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  5. The integration of STEM with the Arts, commonly referred to as STEAM, recognizes the need for human skill, creativity, and imagination in technological innovations and solutions of real-world technical problems. The STEAM paradigm changes the dominant “chalk and talk” lecture and “closed-ended” problem-solving orientation of traditional engineering pedagogy to a hands-on, studio-based, and open-ended creative learning approach, typical in art education. A growing body of literature has provided evidence of the favorable impact of situating STEAM in K-16 education. The long-term objective of this work is to promote creativity in engineering students by integrating learning methods and environments from the Arts into graduate STEM education. To this end, an integrating engineering, technology and art (ETA) educational model is developed and is currently being tested. This ETA educational model systematically merges technical instruction with studio-based pedagogy. The ETA model consists of three courses, which were piloted in the year 2017. In each course, engineering and art instructors and students collaborated for 15 weeks on design projects. These projects ranged from drones to architectural installations. 
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