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Articles 17461 - 17490 of 196033

Full-Text Articles in Engineering

Comparative Analysis Of Motors With Inner And Outer Reluctance Rotors And Pm Stators, Oluwaseun A. Badewa, Dan M. Ionel Jun 2024

Comparative Analysis Of Motors With Inner And Outer Reluctance Rotors And Pm Stators, Oluwaseun A. Badewa, Dan M. Ionel

Electrical and Computer Engineering Graduate Research

This paper presents a comparison of special outer and inner reluctance rotor motor topologies with permanent magnet (PM) stators having toroidal AC windings. A systematic approach is taken to study and discuss the design geometries, the respective impact on performance, and adoption of technological advancements such as stator-only cooling and hair-pin winding for high slot fill factor. Parametric FEA models are developed for both topologies, and design of experiments (DoE)-based sensitivity analysis is used to study the effect of independent variables on specific performance metrics such as torque, motor loss, torque ripple, and power factor. Inner and outer rotor topologies …

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Sensorless Control Of Low Inductance Coreless Afpm Machines For Fault-Tolerant Operation Of Propulsion Systems, Yaser Chulaee, Ali Mohammadi, Aaron M. Cramer, Dan M. Ionel Jun 2024

Sensorless Control Of Low Inductance Coreless Afpm Machines For Fault-Tolerant Operation Of Propulsion Systems, Yaser Chulaee, Ali Mohammadi, Aaron M. Cramer, Dan M. Ionel

Electrical and Computer Engineering Graduate Research

In motor-drive systems utilized in safety-critical applications and demanding conditions like electric aircraft propulsion systems, the reliability of the system is greatly affected by position sensors, given their susceptibility within the motor drive system. Consequently, there is a need to eliminate sensors in vector-controlled motor drives to decrease overall hardware complexity and expenses, bolster the mechanical durability and dependability of the drive system. In this paper, a fault-tolerant sensorless control system for low inductance coreless axial flux PM (AFPM) machines, integrated into electric aircraft propulsion systems, is introduced. The proposed control system spans a wide operating range, from zero to …

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Fault-Tolerant Axial Flux Coreless Pm Machines With Independent Phase Modules, Yaser Chulaee, Ali Mohammadi, Dan M. Ionel, Matin Vatani Jun 2024

Fault-Tolerant Axial Flux Coreless Pm Machines With Independent Phase Modules, Yaser Chulaee, Ali Mohammadi, Dan M. Ionel, Matin Vatani

Electrical and Computer Engineering Graduate Research

In this paper, a fault-tolerant two-phase high power coreless axial flux PM (AFPM) machine with a modular structure is introduced. The performance of this machine, in terms of torque, power density, and efficiency, is compared with its three-phase counterpart configuration based on finite element analysis (FEA) and experimental results. The fault tolerance of these two configurations, considering the control systems, is also compared. A detailed power loss breakdown for the prototype two-phase and three-phase printed circuit board (PCB) stator coreless AFPM machines derived from experiments is presented, showcasing that the introduced fault-tolerant two-phase machine has comparable performance and efficiency, while …

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High-Power Polyphase Pcb-Type Inductive Coupler For Wireless Electric Vehicle Charging, Donovin D. Lewis, Omer Onar, Lucas Gastineau, John F. Eastham, Dan M. Ionel Jun 2024

High-Power Polyphase Pcb-Type Inductive Coupler For Wireless Electric Vehicle Charging, Donovin D. Lewis, Omer Onar, Lucas Gastineau, John F. Eastham, Dan M. Ionel

Electrical and Computer Engineering Graduate Research

The cost and manufacturing difficulty of traditionally wound coils for wireless charging of electric vehicles has led to the exploration of alternative manufacturing for scalable deployment at a range of rated powers. A rotating-field polyphase wireless coupler is developed with balanced fully pitched coils which are not possible with conventional Litz wire. The usage of printed circuit board (PCB) technology is proposed for the innovative construction at large dimensions due to reduced cost, increased ease of manufacturability, and potential geometric customization compared to would coils. Design considerations specific to PCBs are detailed for wireless power transfer coils including advantages such …

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Comparative Analysis Of Vernier Machines With Spoke, Surface Mounted, And Halbach Pm Rotors For In-Wheel Traction, Ali Mohammadi, Aaron M. Cramer, Dan M. Ionel Jun 2024

Comparative Analysis Of Vernier Machines With Spoke, Surface Mounted, And Halbach Pm Rotors For In-Wheel Traction, Ali Mohammadi, Aaron M. Cramer, Dan M. Ionel

Electrical and Computer Engineering Graduate Research

Axial-flux Permanent Magnet (AFPM) machines are well-suited for in-wheel traction in electric vehicles due to their compact structure and higher torque density. This paper presents a large-scale design optimization of an axial-flux permanent magnet vernier machine (PMVM) of the MAGNUS type with a double stator configuration. The active stator features double layer wound coils, while the passive stator is unwound but has a similar profile. The reference design employs a rotor with permanent magnets (PMs) arranged in a spoke-type field intensifying pattern, providing high flux concentration. Design optimization was performed using 3-D electromagnetic Finite Element Analysis (FEA) and the Differential …

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On The Optimal Design Of Coreless Afpm Machines With Halbach Array Rotors For Electric Aircraft Propulsion, Matin Vatani, Yaser Chulaee, Ali Mohammadi, David R. Stewart, John F. Eastham, Dan M. Ionel Jun 2024

On The Optimal Design Of Coreless Afpm Machines With Halbach Array Rotors For Electric Aircraft Propulsion, Matin Vatani, Yaser Chulaee, Ali Mohammadi, David R. Stewart, John F. Eastham, Dan M. Ionel

Electrical and Computer Engineering Graduate Research

This paper presents and evaluates the optimal design of a coreless axial flux permanent magnet (AFPM) motor for electric aircraft propulsion. Ferromagnetic cores are entirely removed from the machine’s structure to improve the specific power density and efficiency. An approach for envelope design optimization of the proposed motor is introduced, considering the polarity as an independent variable and employing an evolutionary algorithm and 3D Finite Element Analysis (FEA). In addition to the proposed electric motor’s electromagnetic performance, fault-tolerant capability and thermal management are considered in the optimization procedure. The optimization results and similar studies from power electronic and thermal management …

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A New Design Strategy For Sizes Of Polymer Gel Treatments Derived From A Comprehensive Assessment Of Their Case Histories, Munqith Aldhaheri, Abdullah Almansour, Na Zhang, Mingzhen Wei, Baojun Bai Jun 2024

A New Design Strategy For Sizes Of Polymer Gel Treatments Derived From A Comprehensive Assessment Of Their Case Histories, Munqith Aldhaheri, Abdullah Almansour, Na Zhang, Mingzhen Wei, Baojun Bai

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The incentive to revive brownfield oil production extends the interest to apply polymer gel treatments in injection wells. Virtually, volumes of previous remediations implemented in similar reservoir types are used to size new jobs. Such an analogy-based design procedure imposes a need to evaluate the most frequent designs for each reservoir type based on a comprehensive field survey. This survey provides a new treatment sizing strategy for polyacrylamide-polymer bulk gels by reviewing their field applications in 653 injection wells. The new strategy proposes using the average and most frequent gel volumes per reservoir type as an initial estimate of the …

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Lithospheric Evolution Of The South-Central United States Constrained By Joint Inversion Of Receiver Functions And Surface Wave Dispersion, Tuo Wang, Stephen S. Gao, Kelly H. Liu, Kevin L. Mickus, Ling Chen Jun 2024

Lithospheric Evolution Of The South-Central United States Constrained By Joint Inversion Of Receiver Functions And Surface Wave Dispersion, Tuo Wang, Stephen S. Gao, Kelly H. Liu, Kevin L. Mickus, Ling Chen

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

In the present study, we use broadband seismic data recorded by 190 stations of the EarthScope program's Transportable Array to construct a 3-D shear wave velocity model for the upper 180 km using a non-linear Bayesian Monte-Carlo joint inversion of receiver functions (RFs) and Rayleigh wave dispersion curves. Ambient noise and teleseismic data are used for obtaining Rayleigh wave phase velocity dispersion curves. A resonance removal filtering technique is applied to the RFs contaminated by reverberations from the thick sedimentary layers that cover most of the region. Our observations of the higher crustal shear velocities (∼3.40 km/s) beneath the Sabine …

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Ace Mentor Program - Central Coast Chapter, Brayden Samuel Groshart Jun 2024

Ace Mentor Program - Central Coast Chapter, Brayden Samuel Groshart

Construction Management

For my senior project, I established a chapter of the ACE (Architecture, Construction, and Engineering) Mentor Program in San Luis Obispo, California. This program provides high school students with hands-on experience and exposure to careers in the architecture, construction, and engineering industries. The program spanned eight weeks, balancing theoretical knowledge and practical application. The curriculum began with sessions on the fundamentals of architecture, engineering, and construction. In order to expose the students to real world practices, we organized tours of an architecture firm, an engineering firm, and an active construction site. These visits allowed students to engage with professionals, observe …

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Slo Water Treatment Facility Grill Retrofit, Liam Dolan Jun 2024

Slo Water Treatment Facility Grill Retrofit, Liam Dolan

Construction Management

The San Luis Obispo Water Treatment Facility is a vital facility that provides water to all of San Luis Obispo. The facility runs twenty-four hours a day and constantly has long shifts for those who work there. The water treatment facility has a small, rusted Santa Maria grill that is rarely used because of its condition, and they were in need of a new grill that employees could use to make lunches. The water treatment facility has plans to build an outdoor dining space for employees, and my goal for this retrofitted grill project is to help enhance that space …

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Construction Of Concrete Shear Wall & Modular Foundations - Procurement And Quality Control, Justin J. Coffin Jun 2024

Construction Of Concrete Shear Wall & Modular Foundations - Procurement And Quality Control, Justin J. Coffin

Construction Management

This project details the planning, construction, quality control, and logistics processes throughout the construction of a concrete shear wall and modular footings. The project focused on constructing the wall and footings as they were designed to ensure they meet strength parameters to be used in the High Bay Lab at California Polytechnic State University in San Luis Obispo for seismic testing. The complex designs, encompassing dense rebar gages and post tensioned bars, required extensive hours of labor and quality control. This paper will cover the main phases of the construction process and how they were acquired. Furthermore, the considerations taken …

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Construction Of Lightly Reinforced Concrete Shear Wall And Footings, Luke Jackson Method Jun 2024

Construction Of Lightly Reinforced Concrete Shear Wall And Footings, Luke Jackson Method

Construction Management

This paper details the construction of two cast in place foundations as well as a lightly reinforced cast in place wall. The project, located inside the high bay, provides the Architectural Engineering (ARCE) department with an opportunity to test Fiber Reinforced Polymer wrap as a retrofitting option for walls dating back to pre-1980s. Due to site conditions, and project design, this project required extensive planning and communication within our team, faculty advisors, and shop technicians. This paper will discuss the phasing of construction and procurement of material that was required for the completion of this project. It also aims to …

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Resources To Support Adu Construction, Eleanor Rheingans Jun 2024

Resources To Support Adu Construction, Eleanor Rheingans

Construction Management

This survey examines whether cities with a higher number of online resources will result in a higher proportion of ADU permits and a lower wait time for approval. Some cities have offered online resources directly related to the ADU permitting and construction process. The seven online resources were selected based on interviews with developers. Data used is from 2018 to 2023. Other factors seem to affect the number of permits issued more than resources the cities post for public access. While developers do want the resources cities are currently offering, there are some gaps, particularly records of past permit costs …

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Designing, Estimating, And Building A Deck And Overhang For The Paso Robles Police Department Shooting Range, Nicklaus Amil Zenner, Benjamin Henry Gallagher Jun 2024

Designing, Estimating, And Building A Deck And Overhang For The Paso Robles Police Department Shooting Range, Nicklaus Amil Zenner, Benjamin Henry Gallagher

Construction Management

This paper covers the design, estimating, and construction process by a team of students from Cal Poly to provide a deck and overhang for the Paso Robles Police Department Shooting Range. The project, initiated in the winter of 2024, aimed to provide a durable, functional, and aesthetically pleasing deck and overhang suitable for a barbecue and lounge area. The paper focuses on the design and estimation phases, as well as material procurement and construction. Through meetings with the client, the team developed a design that met the police department's criteria for functionality, durability, and cost. The design process involved collaboration …

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Skip The Grid: Navajo Nation Solar Power Project, Nathan Kealy Haub Jun 2024

Skip The Grid: Navajo Nation Solar Power Project, Nathan Kealy Haub

Construction Management

Skip the Grid, an initiative aimed at empowering communities in need was brought to life through the collaborative efforts of California Polytechnic State University San Luis Obispo (Cal Poly) students, industry partners like SOLV Energy, and the educational non-profit organization Heart of America (HOA). This project was a true testament to the power of teamwork and innovation. Our mission was to assist families of school-aged children in the Navajo Nation by providing them with solar energy systems, including batteries and lighting. We aimed to create a lasting impact by equipping these families with essential resources. In addition, we integrated educational …

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San Luis Obispo High School Ffa Barn Demolition: Disposal Of Material, Jake B. Schulman Jun 2024

San Luis Obispo High School Ffa Barn Demolition: Disposal Of Material, Jake B. Schulman

Construction Management

San Luis Obispo High School’s FFA program needed to upgrade its deteriorating pig barn, involving three key scopes of work: demolition of the existing structure, proper disposal of materials, and reconfiguration of pig pens and water lines. This project required skills in demolition, framing, and plumbing, all of which our team learned during construction management courses at Cal Poly. The demolition entailed the complete removal of a barn with metal roof panels, wood trusses, joists, studs, and plywood sheathing. Proper disposal of these materials was crucial and will be detailed in this paper, with a brief discussion on demolition and …

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Recycled And Waste Glass As A Sustainable Substitute For Aggregates And Cement In Concrete, Griffin Powers Finnane Jun 2024

Recycled And Waste Glass As A Sustainable Substitute For Aggregates And Cement In Concrete, Griffin Powers Finnane

Construction Management

Besides water, concrete is the most widely used material in the world. The production of Portland cement, the most crucial ingredient in a concrete mix, significantly contributes to global carbon dioxide emissions, accounting for 7-8% of the total. The majority of these emissions result from the cement production process, which involves kilns powered by greenhouse gas-producing sources. Additional emissions come from the heavy diesel equipment used to load and haul aggregates to batch plants. Although the construction industry is adopting more sustainable building techniques and materials, the basic concrete mix remains largely unchanged, continuing to contribute heavily to carbon emissions. …

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Iron Filings Impact On The Compressive Strength Of Concrete, Dominic Daniel Aceves Jun 2024

Iron Filings Impact On The Compressive Strength Of Concrete, Dominic Daniel Aceves

Construction Management

In this study, compression tests were performed on three different mix designs of concrete to evaluate the effects of iron filings as an admixture to concrete. The first mix design served as the control mix, being the variable that the other two mixes will be based off. The second mix design was the same as the first mix design, but with an added 12 ounces of iron filings. The third mix design was, again, the same as the first mix design, but with an added 24 ounces of iron filings doubling that of the second mix design. The objective of …

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Exploring The Role Of Construction Technology Copilots, James S. Thielmann Jr. Jun 2024

Exploring The Role Of Construction Technology Copilots, James S. Thielmann Jr.

Construction Management

In the rapidly evolving construction industry, the adoption of software solutions is essential for enhancing efficiency, reducing costs, and ensuring timely project delivery. This paper assesses the effectiveness and usefulness of existing construction software solutions, focusing on their functionalities, strengths, and limitations. Among the prominent solutions gaining traction are Trunk.Tools, Constructable.ai, and ProjectEngineer.ai. The construction industry, although historically slower to adopt new technologies, stands to gain a great deal from these tools in terms of project management and performance. This research includes a thorough examination of ProjectEngineer.ai's reach in the market, feature development, and growing uptake among experts in the …

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Moringa Connect: Design And Fabrication Of The Drum For A Moringa Leaf Dryer Prototype, Braden Deck Jun 2024

Moringa Connect: Design And Fabrication Of The Drum For A Moringa Leaf Dryer Prototype, Braden Deck

Construction Management

Moringa Connect, founded in 2013 by MIT alumnus Kwami Williams, supports over 5,000 African farmers, primarily in Ghana, by providing a direct sales, manufacturing, and shipping platform for nutrient-dense moringa leaves. Despite significant social and economic benefits for the local farmers, the current drying process in Accra, Ghana, is inefficient, requiring extensive human handling. To address this, a team of five Cal Poly students partnered with Moringa Connect to design a prototype rotating hopper to streamline the drying process and reduce production costs. The project faced numerous challenges, including material sourcing constraints in Ghana and the need for extensive fabrication …

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Skip The Grid: Delivering Power To The Navajo Nation, William Jacob Bellios Jun 2024

Skip The Grid: Delivering Power To The Navajo Nation, William Jacob Bellios

Construction Management

Skip the Grid is a groundbreaking initiative designed to bring sustainable, off-grid power solutions to isolated communities facing significant challenges, such as the Navajo Nation. This collaborative effort involved an interdisciplinary team of California Polytechnic State University, San Luis Obispo (Cal Poly) SOLV Energy, and Heart of America (HOA). Due to the vast and dispersed nature of the reservation, a historical lack of government investment, and the severe impact of COVID-19 on the community, many homes are without electricity. This project aimed to address these issues by installing Goal Zero solar panels, battery systems, and lighting in 24 homes of …

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Gateway Decathlon: Carbon Calculations Of An Offsite Residential Construction, Isaac Robert Rubio Jun 2024

Gateway Decathlon: Carbon Calculations Of An Offsite Residential Construction, Isaac Robert Rubio

Construction Management

This senior project delves into a comprehensive calculation of carbon emissions for both efficiency and sustainability within the realm of modular construction. A material takeoff of the building was performed, allowing for an accurate measurement of materials and their respective EPD (Environmental Product Declaration) values. After material selection, a final carbon calculation of the building was calculated. Carbon emission calculations were performed on the current Revit Model allowing for a full-scale analysis, from Cradle to Gate, of the offsite residential unit. The results show that the total initial embodied carbon emissions of the unit is 9241 (kg-CO2e), representing the total …

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Consumption And Waste For Hydrating Workers With Single Use Plastic Bottles, James Colnett Jun 2024

Consumption And Waste For Hydrating Workers With Single Use Plastic Bottles, James Colnett

Construction Management

The construction industry significantly contributes to environmental waste, notably through the extensive use of plastic water bottles for hydrating field personnel. This case study investigates the hydration practices of a midsize construction company in the Bay Area, focusing on the volume of plastic waste generated and potential sustainable alternatives. Data were collected via surveys sent to 15 employees, revealing that approximately 130,416 plastic bottles are used annually across 11 project sites. Despite the convenience and compliance with OSHA regulations, the reliance on single-use plastic bottles presents severe environmental and health concerns, such as resource depletion and microplastic pollution. Survey results …

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San Luis Obispo High School Ffa Swine Barn Demolition And Enclosure Reconfiguration, John F. Spurlock Jun 2024

San Luis Obispo High School Ffa Swine Barn Demolition And Enclosure Reconfiguration, John F. Spurlock

Construction Management

The San Luis Obispo High School (SLOHS) FFA program required an upgrade to its deteriorating swine barn. This project came in three unique scopes of work: demolition of the existing barn, proper disposal of materials, and reconfiguration of the enclosure and water lines. This paper will cover specifically the reconfiguration of the enclosures and the redesign of the watering system. This phase of the project required skills in framing and plumbing, which our team had absorbed during specific construction management courses at Cal Poly. The reconfiguration included framing and securing a long span of fencing along the northern side of …

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Exploring Mass Timber And Mitek Posi-Strut System In Modern Construction, Matthew N. Maloney Jun 2024

Exploring Mass Timber And Mitek Posi-Strut System In Modern Construction, Matthew N. Maloney

Construction Management

This study evaluates the performance, cost-effectiveness, and constructability of two different truss systems by constructing identically sized mockup models. The comparison focuses on the top chord POSI-Strut Metal Web System and the bottom chord truss system, both utilizing Boise Cascade LVL engineered lumber. Our findings reveal that the top chord POSI structure truss system is more cost-effective and time-efficient compared to the bottom chord truss system. The top chord system's design reduces material costs and speeds up construction time, making it an attractive option for projects with tight budgets and schedules. However, the top chord POSI-Strut Metal Web System has …

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The Future Of Fiberglass Rebar In Concrete Structures, Dillon Michael Elliott Jun 2024

The Future Of Fiberglass Rebar In Concrete Structures, Dillon Michael Elliott

Construction Management

In the working elements of the construction industry, the strive for materials that aim for strength, durability, and sustainability are never-ending. For traditional steel reinforcement this material faces inevitable challenges over time such as corrosion, weight of material, and environmental concerns. However with the emergence of fiberglass rebar, the negative impacts we see from traditional steel rebar may be resolved within the industry of construction. This paper aims to explore and propose a different alternative to reinforcement in concrete structures with the use and integration of fiberglass. The effectiveness which fiberglass as a reinforcement material offers will be investigated throughout …

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Skip The Grid: Solar Panel And Battery Installations In Navajo Nation, Samir S. Ramanathan Jun 2024

Skip The Grid: Solar Panel And Battery Installations In Navajo Nation, Samir S. Ramanathan

Construction Management

Skip the Grid is a collaborative effort to bring off-grid power to communities that are isolated and experience inequalities, such as the Navajo Nation, in order to enhance their quality of life. This effort involved an interdisciplinary team of California Polytechnic State University, San Luis Obispo (Cal Poly) students, SOLV Energy, and Heart of America (HOA). Due to the vast nature of the reservation, lack of government focus in the region, and Covid’s severe damage to the community, a large number of homes of school age children do not have power. This project installed solar panels, battery systems, and lights …

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Skip The Grid: Bringing Power To Navajo Nation Students, Colette Burd Jun 2024

Skip The Grid: Bringing Power To Navajo Nation Students, Colette Burd

Construction Management

Skip the Grid is an annual joint initiative facilitated by the non-profit Heart of America involving California Polytechnic State University, San Luis Obispo (Cal Poly) students and faculty, and SOLV Energy. The Skip the Grid project brings power and lighting to Navajo Nation families with school-age children by installing a self-contained solar battery system. Completed from March 24th through March 28th of 2024, this year the Skip the Grid project brought photovoltaic energy systems with solar panels, a battery, lights, and outlets to 24 homes, benefiting over 100 students in the Consolidated School District within the Navajo Nation. For the …

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Optimizing 3d Printed Concrete Effificeny: A Case Study Of Emergent 3d'S Iterative Process Improvement, Michael Stearns Jun 2024

Optimizing 3d Printed Concrete Effificeny: A Case Study Of Emergent 3d'S Iterative Process Improvement, Michael Stearns

Construction Management

This case study looks into the advancement of 3D printed concrete (3DPC) technology and its application by Emergent 3D, a company dedicated to addressing California's housing crisis through low-cost, sustainable construction. Emergent 3D, which was formed in response to the 2018 Carr Fire, uses 3DPC to quickly and economically design energy-efficient homes. Unlike traditional construction processes, 3DPC constructs buildings or walls layer by layer using computer-generated designs, reducing material and labor expenses. This case study focuses on Emergent 3D's first project, Enterprise Park, which gave them significant insights on improving the 3DPC process. This case study identifies crucial improvements in …

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Son Care Foundation – Lean To Shade Structure Design And Construction, Ryan Joseph Mccann Jun 2024

Son Care Foundation – Lean To Shade Structure Design And Construction, Ryan Joseph Mccann

Construction Management

This paper discusses the design and construction of a lean-to-shade structure built for the Son Care Foundation in San Luis Obispo. The Son Care Foundation is a nonprofit organization that raises guide dogs for veterans and first responders with PTSD. This shade structure is 16 feet long and 6 feet wide, its height slopes from 9 feet in the front down to 8 feet in the back creating a roof pitch of 2:12. The sheet metal roof also has an overhang of approximately 1 foot. As requested by the client, the shade structure was designed to fit the aesthetic of …

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