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Design and Development of a Half-Bridge LLC Resonant Converter Laboratory Module
No full textResonant DC-DC converters have become a well-known solution in power supplies due to their ability to improve efficiency by utilizing soft-switching techniques. This further has caused a growing interest in industry to use these converters for high-switching-frequency, high-efficiency, and high-power applications such as EV charging stations, photovoltaic systems, battery chargers, etc. One particular resonant topology that has gained popularity in recent years is the LLC resonant converter. Due to the prevalent use of the LLC resonant converter, it is therefore crucial for students preparing for a career path in power electronics to become well-versed in the concept and implementation of the converter. This thesis presents the design and development of a half-bridge LLC resonant converter laboratory module that allows students to gain a thorough understanding of the converter through a hands-on laboratory experiment. With the constructed 5 V output lab module, students can change the converter’s switching frequency by adjusting the input voltage (70 V, 80 V, 100 V) and conduct performance tests on the three different operating modes: Below (83kHz), At (97kHz), and Above (116kHz) Resonant frequencies. Safety measures are also incorporated in the lab module, which include a fuse, reverse polarity protection, and a plexiglass housing. Computer simulation using SIMPLIS verifies the functionality of the half-bridge resonant circuit. Hardware tests performed on the constructed lab module demonstrate that the lab module serves as a safe learning tool for students to gain understanding of the concepts, operation, and performance of the half-bridge LLC resonant converter
Banach Algebras and the Gelfand Theory of Group Algebras on Locally Compact Abelian Groups
No full textA Banach algebra is a complex algebra that is simultaneously a Banach space in which the norm is submultiplicative. Notably, with the convolutional product is an Abelian, non-unital Banach algebra that admits an approximate identity. We rectify lacking a unit via the unitization with identity . Unitization opens the discussion to the spectrum of a Banach algebra element, in which the spectrum is a nonempty, compact subset of the complex plane. The spectrum of an Abelian Banach algebra is fully characterized with multiplicative linear functionals, and we prove that the Fourier transform is the unique multiplicative linear functional on . From this, the spectrum of an element is precisely the closure of the range of the Fourier transform of . We then generalize to the study of for a locally compact Abelian group and establish the bijection between the dual group and the Gelfand space . When considering , the Fourier transform is precisely the Gelfand transform. Lastly, we introduce Pontryagin duality and a structure theorem for the Gelfand representation of for , where
Dr. Eve Hinman, A Pioneer in the Protective Design Industry
No full textThis senior project carries on prior work to develop an educational material on the notable female protective design engineer Dr. Eve Hinman, initiated by Cal Poly Architectural Engineering students Michelle Dennin and Paulina Robles in collaboration with faculty member Dr. Anahid Behrouzi. To gain a deeper understanding of Dr. Eve Hinman’s impact on the industry, the project team conducted extensive research into her career including interviews with former employees of the firm that she founded and led, Hinman Consulting Engineers (HCE), and an analysis of the recently acquired collection of library material gifted by HCE to Cal Poly. After completing research, the project team produced three deliverables: A Timeline of Dr. Eve Hinman Alongside Influential Blasts, A Protective Design Family Tree, and a Structural Engineers Association of Northern California (SEAONC) Hensolt Legacy Project entry. The first is a timeline that illustrates the parallel between major blast events and her work throughout her career, highlighting her contributions to the evolution of protective design. The second is a family tree that visually represents her widespread influence across the industry, showing how many current protective design engineers can trace their professional roots back to Hinman Consulting Engineers that she founded and led. The final product is the Hensolt Legacy Project paper, which formally recognizes Dr. Eve Hinman as a notable Northern California engineer and celebrates her enduring impact on the structural engineering community. Together, these deliverables aim to shine a light on the career of a significantly influential structural engineer who carved out a niche in a highly specialized and challenging field. By sharing her story, the project team hopes to inspire the next generation of engineers to pursue their passions and make meaningful contributions to the profession
The Suture Guide
Get PDFIn the surgical field and specifically wound closure, there is a growing demand for techniques that allow surgeons to quickly, accurately, and ergonomically close surgical wounds while still optimizing patient recovery and not compromising the cosmetic appearance in wound closure. Currently more advanced and developed products exist for laparoscopic suturing, but not for superficial suturing. This project aims to find a way to close the most superficial layer of the skin in surgical incisions that is faster and more comfortable than current suturing techniques. The design process began with stakeholder interviews and market research, identifying key shortcomings of current manual suturing devices. These insights were used to guide ideations, which were 3D-printed for rapid iteration, leading the team to develop a final prototype allowing for extensive testing and refinement. The testing and analysis of the Suture Guide Device provided key insights into its mechanical performance, usability, and overall functionality, highlighting both areas of success and aspects requiring improvement
