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open access

Accelerated Corrosion Test with Operation Simulation of All-Aluminum Microchannel Heat Exchangers

Description: The HVAC&R industry is looking to transition from copper-aluminum heat exchangers to all-aluminum microchannel technology. The want for the transition stemmed from seeing the performance improvement of all-aluminum microchannel radiators in the automotive industry. Applications differ between the two industries; therefore, applying this technology for HVAC&R use must be validated. Research towards operating modes of an all-aluminum heat exchanger in a defined corrosive environment will provide … more
Date: May 2016
Creator: Vaughan, Haydn
Item Type: Refine your search to only Thesis or Dissertation
open access

Analytical Model of Cold-formed Steel Framed Shear Wall with Steel Sheet and Wood-based Sheathing

Description: The cold-formed steel framed shear walls with steel sheets and wood-based sheathing are both code approved lateral force resisting system in light-framed construction. In the United States, the current design approach for cold-formed steel shear walls is capacity-based and developed from full-scale tests. The available design provisions provide nominal shear strength for only limited wall configurations. This research focused on the development of analytical models of cold-formed steel framed s… more
Date: May 2013
Creator: Yanagi, Noritsugu
Item Type: Refine your search to only Thesis or Dissertation
open access

Bearing Strength of Cold Formed Steel Bolted Connections in Trusses

Description: The existing design provision in North American Specification for Cold- Formed Steel Structural Member (AISI S100) for the bearing strength of bolted connections were developed from tests on bolted connected sheets which were restrained by bolt nut and head with or without washers. However, in the cold-formed assemblies, particularly in trusses, the single bolt goes through both sides of the connected sections, making the connected sheets on each side unrestrained. the warping of the unrestrain… more
Date: May 2012
Creator: Panyanouvong, Mark
Item Type: Refine your search to only Thesis or Dissertation
open access

Cold-formed Steel Framed Shear Wall Sheathed with Corrugated Sheet Steel

Description: Incombustibility is one important advantage of the sheet steel sheathed shear wall over wood panel sheathed shear wall. Compared to shear wall sheathed with plywood and OSB panel, shear wall sheathed with flat sheet steel behaved lower shear strength. Although shear wall sheathed with corrugated sheet steel exhibited high nominal strength and high stiffness, the shear wall usually behaved lower ductility resulting from brittle failure at the connection between the sheathing to frames. This rese… more
Date: May 2013
Creator: Yu, Guowang
Item Type: Refine your search to only Thesis or Dissertation

Cold-Formed Steel Member Connections Using BAC Screw Fasteners

Description: In this project, the main research objective is intend to seek criteria for evaluating the capacity of BAC screw fasteners with mixed configuration of waterproof seal washer, sealer tape and different pre-drill holes to determine shear and tension strength values for the screws used in cold-formed steel connections. The thesis presents the design methods and test program conducted to investigate the behavior and strength of the screw connections in shear and tension test. Test results were comp… more
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Date: May 2019
Creator: Li, Xun
Item Type: Refine your search to only Thesis or Dissertation
open access

Corrosion Protection of Low Carbon Steel By Cation Substituted Magnetite

Description: Surfaces of low carbon steel sheet were modified by exposure to highly caustic aqueous solutions containing either chromium or aluminum cations. Corrosion resistances of such surfaces were compared with that of steel surfaces exposed to plain caustic aqueous solution. In all cases a highly uniform, black coating having a spinel structure similar to magnetite (Fe3O4) was obtained. The coated steel surfaces were characterized using X-ray photoelectron spectroscopy (XPS), scanning electron micros… more
Date: May 2013
Creator: Phadnis, Ameya
Item Type: Refine your search to only Thesis or Dissertation
open access

The Design and Development of Lightweight Composite Wall, Roof, and Floor Panels for Rigid Wall Shelter

Description: This thesis presents a research effort aimed at developing a stronger, lighter, and more economic shelter using rigid wall panels. Reported herein is insulation research, wall and roof panel design and testing, floor section modeling and strength calculations, and cost and weight calculations. Beginning stages focus on developing solid wall and roof panels using cold-formed steel corrugated sheathing and members, as well as polyurethane spray foam for insulation. This research includes calculat… more
Date: May 2018
Creator: Artman, Jeremy J
Item Type: Refine your search to only Thesis or Dissertation
open access

Design, Modeling, and Experiment of a Piezoelectric Pressure Sensor based on a Thickness-Shear Mode Crystal Resonator

Description: This thesis presents the design, modeling, and experiment of a novel pressure sensor using a dual-mode AT-cut quartz crystal resonator with beat frequency analysis based temperature compensation technique. The proposed sensor can measure pressure and temperature simultaneously by a single AT-cut quartz resonator. Apart from AT-cut quartz crystal, a newly developed Langasite (LGS) crystal resonator is also considered in the proposed pressure sensor design, since LGS can operate in a higher tempe… more
Date: May 2017
Creator: Pham, Thanh Tuong
Item Type: Refine your search to only Thesis or Dissertation
open access

Direct Strength Method for Web Crippling of Cold-formed Steel C-sections

Description: Web crippling is a form of localized buckling that occurs at points of transverse concentrated loading or supports of thin-walled structural members. The theoretical computation of web crippling strength is quite complex as it involves a large number of factors such as initial imperfections, local yielding at load application and instability of web. The existing design provision in North American specification for cold-formed steel C-sections (AISI S100, 2007) to calculate the web-crippling str… more
Date: May 2013
Creator: Seelam, Praveen Kumar Reddy
Item Type: Refine your search to only Thesis or Dissertation
open access

Effects of Processing Techniques on Mechanical Properties of Selected Polymers

Description: The mechanical properties of a polymer represent the critical characteristics to be considered when determining the applications for it. The same polymer processed with different methods can exhibit different mechanical properties. The purpose of this study is to investigate the difference in mechanical properties of the selected polymers caused by different processing techniques and conditions. Three polymers were studied, including low density polyethylene (LDPE), polypropylene (PP), and NEXP… more
Date: May 2013
Creator: Dong, Yao
Item Type: Refine your search to only Thesis or Dissertation
open access

Effects of Rebar Temperature and Water to Cement Ratio on Rebar-Concrete Bond Strength of Concrete Containing Fly Ash

Description: This research presents the results on an experimental investigation to identify the effects of rebar temperature, fly ash and water to cement ratio on concrete porosity in continuously reinforced concrete pavements (CRCP). Samples were cast and analyzed using pullout tests. Water to cement ratio (w/c) and rebar temperature had a significant influence on the rebar-concrete bond strength. The 28-day shear strength measurements showed an increase in rebar-concrete bond strength as the water to cem… more
Date: May 2010
Creator: Pati, Ardeep Ranjan
Item Type: Refine your search to only Thesis or Dissertation
open access

Innovative Cold-Formed Steel Shear Walls with Corrugated Steel Sheathing

Description: This thesis presents two major sections with the objective of introducing a new cold-formed steel (CFS) shear wall system with corrugated steel sheathings. The work shown herein includes the development of an optimal shear wall system as well as an optimal slit configuration for the CFS corrugated sheathings which result in a CFS shear wall with high ductility, high strength, high stiffness and overall high performance. The conclusion is based on the results of 36 full-scale shear wall tests pe… more
Date: May 2016
Creator: Mahdavian, Mahsa
Item Type: Refine your search to only Thesis or Dissertation
open access

Investigation of Spray Cooling Schemes for Dynamic Thermal Management

Description: This study aims to investigate variable flow and intermittent flow spray cooling characteristics for efficiency improvement in active two-phase thermal management systems. Variable flow spray cooling scheme requires control of pump input voltage (or speed), while intermittent flow spray cooling scheme requires control of solenoid valve duty cycle and frequency. Several testing scenarios representing dynamic heat load conditions are implemented to characterize the overall performance of variable… more
Date: May 2017
Creator: Yata, Vishnu Vardhan Reddy
Item Type: Refine your search to only Thesis or Dissertation
open access

Mechanical Characterization of A2 and D2 Tool Steels By Nanoindentation

Description: Nanoindentation technique was used to investigate the surface properties of A2 and D2 tool steel subjected to different heat treatments. the mechanical characteristics of these two easily available tool steels were studied based on microstructural images obtained from SEM, the grain growth after heat treatment using X-ray diffraction method and nanoindentation technique. the investigation showed that a single nanoindentation result can explain how heat treatment influences reliability and failu… more
Date: May 2012
Creator: Okafor, Uzochukwu Chimezie
Item Type: Refine your search to only Thesis or Dissertation
open access

Nominal Shear Strength of Cold-formed Steel Shear Walls Using Osb Sheathing

Description: In the cold-formed steel construction, the oriented strand board is a common material for shear wall sheathing. an OSB is made by using wood chips as raw materials that undergo high temperature pressing to create a multi-larger structure material. Due to the OSB having a high strength in shear, it is an important material used in the construction field. the thesis is trying to verify published nominal shear strength in AISI-213-07 in the first part. This objective has two parts: the first part … more
Date: May 2012
Creator: Li, Chao
Item Type: Refine your search to only Thesis or Dissertation
open access

Ota-quadrotor: An Object-tracking Autonomous Quadrotor for Real-time Detection and Recognition

Description: The field of robotics and mechatronics is advancing at an ever-increasing rate and we are starting to see robots making the transition from the factories to the workplace and homes as cost is reduced and they become more useful. In recent years quadrotors have become a popular unmanned air vehicle (UAV) platform. These UAVs or micro air vehicles (MAV) are being used for many new and exciting applications such as aerial monitoring of wildlife, disaster sites, riots and protests. They are also be… more
Date: May 2012
Creator: Coelho, Gavin
Item Type: Refine your search to only Thesis or Dissertation
open access

Recommended Modified zone Method Correction Factor for Determining R-values of Cold-Formed Steel Wall Assemblies

Description: Currently, ASHRAE has determined the zone method and modified zone method are appropriate calculation methods for materials with a high difference in conductivity, such as cold-formed steel (CFS) walls. Because there is currently no standard U-Factor calculation method for CFS walls, designers and code officials alike tend to resort to the zone method. However, the zone method is restricted to larger span assemblies because the zone factor coefficient is 2.0. This tends to overestimate the amou… more
Date: May 2011
Creator: Black, John
Item Type: Refine your search to only Thesis or Dissertation
open access

A Study on the System Reliability of Cold-Formed Steel Roof Trusses

Description: This thesis presents a research project aimed at advancing the treatment of cold-formed steel (CFS) structural reliability in roof trusses. Structural design today relies almost exclusively on component-level design, so structural safety is assured by limiting the probability of failure of individual components. Reliability of the entire system is typically not assessed, so in a worst-case scenario the system reliability may be less than the component reliability, or in a best-case scenario the… more
Date: May 2017
Creator: Johnson, Adam M.
Item Type: Refine your search to only Thesis or Dissertation
open access

Topology and Lattice-Based Structural Design Optimization for Additively Manufactured Medical Implants

Description: Topology-based optimization techniques and lattice structures are powerful ways to accomplish lightweight components with enhanced mechanical performance. Recent developments in additive manufacturing (AM) have led the way to extraordinary opportunities in realizing complex designs that are derived from topology and lattice-based structural optimization. The main aim of this work is to give a contribution, in the integration between structural optimization techniques and AM, by proposing a setu… more
Date: May 2019
Creator: Peto, Marinela
Item Type: Refine your search to only Thesis or Dissertation
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