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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
open access

Analytical Model for Lateral Deflection in Cold-formed Steel Framed Shear Walls with Steel Sheathing

Description: An analytical model for lateral deflection in cold-formed steel shear walls sheathed with steel is developed in this research. The model is based on the four factors: fastener displacement, steel sheet deformation, and hold-down deformation, which are from the effective strip concept and a complexity factor, which accounts for the additional influential factors not considered in the previous three terms. The model uses design equations based on the actual material and mechanical properties of t… more
Date: December 2014
Creator: Yousof, Mohamad
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
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
open access

Characterization of Boron Nitride Thin Films on Silicon (100) Wafer.

Description: Cubic boron nitride (cBN) thin films offer attractive mechanical and electrical properties. The synthesis of cBN films have been deposited using both physical and chemical vapor deposition methods, which generate internal residual, stresses that result in delamination of the film from substrates. Boron nitride films were deposited using electron beam evaporation without bias voltage and nitrogen bombardment (to reduce stresses) were characterize using FTIR, XRD, SEM, EDS, TEM, and AFM technique… more
Date: August 2007
Creator: Maranon, Walter

Characterization of Iron Oxide Deposits Formed at Comanche Peak Steam Electric Station

Description: The presence of deposits leading to corrosion of the steam generator (SG) systems is a major contributor to operation and maintenance cost of pressurized water reactor (PWR) plants. Formation and transport of corrosion products formed due to the presence of impurities, metallic oxides and cations in the secondary side of the SG units result in formation of deposits. This research deals with the characterization of deposit samples collected from the two SG units (unit 1 and unit 2) at Comanche P… more
Access: Restricted to the UNT Community Members at a UNT Libraries Location.
Date: May 2003
Creator: Namduri, Haritha
open access

Cold-Formed Steel Bolted Connections Using Oversized and Slotted Holes without Washers

Description: In cold-formed steel (CFS) construction, bolted connections without washers for either oversized or slotted holes may significantly expedite the installation process and lower the cost. However, the North American Specification (AISI S100, 2007) for the Design of Cold-Formed Steel Structural Members requires washers to be installed in bolted connections with oversized or slotted holes. A research project (Phase 1) sponsored by American Iron and Steel Institute (AISI) was recently completed at t… more
Date: August 2010
Creator: Xu, Ke
open access

Cold-Formed Steel Bolted Connections without Washers on Oversized and Slotted Holes

Description: The use of the cold-formed steel sheet bolted connections without washers is so significant; however, the North American Specifications for the Design of Cold Formed Steel Structural Members, NASPEC, doesn't provide provisions for such connections. The bearing failure of sheet and the shear failure of sheet were considered in this study. For the sheet shear strength, it was found that the NASPEC (2007) design provisions can be used for oversized holes in both single and double shear configurati… more
Date: May 2009
Creator: Sheerah, Ibraheem
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

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
Access: Restricted to UNT Community Members. Login required if off-campus.
Date: May 2019
Creator: Li, Xun
open access

Comparative Analysis and Implementation of High Data Rate Wireless Sensor Network Simulation Frameworks

Description: This thesis focuses on developing a high data rate wireless sensor network framework that could be integrated with hardware prototypes to monitor structural health of buildings. In order to better understand the wireless sensor network architecture and its consideration in structural health monitoring, a detailed literature review on wireless sensor networks has been carried out. Through research, it was found that there are numerous simulation software packages available for wireless sensor ne… more
Date: December 2015
Creator: Laguduva Rajaram, Madhupreetha
open access

A Computer-Based Process Control System for a Target Station in a LINAC Facility

Description: An event-driven, sequential, process control system was designed for International Isotopes, Inc., to automate and remotely control a target station at the company's linear accelerator facility. The designed system consisted of two major sections: a software program (virtual instrument), which was developed by LabVIEW, and a hardware interface (FieldPoint Modular Distributed I/O System by National Instrument), which had to be a pre-developed system that did not require customization. The design… more
Date: May 1999
Creator: Al-Shantaf, Abdulraouf O.
open access

Computer Virus Spread Containment Using Feedback Control.

Description: In this research, a security architecture based on the feedback control theory has been proposed. The first loop has been designed, developed and tested. The architecture proposes a feedback model with many controllers located at different stages of network. The controller at each stage gives feedback to the one at higher level and a decision about network security is taken. The first loop implemented in this thesis detects one important anomaly of virus attack, rate of outgoing connection. Tho… more
Date: December 2004
Creator: Yelimeli Guruprasad, Arun

Construction Management Methods and Techniques in Army Tactical Shelter

Description: This thesis presents a research effort aimed at developing using construction methods and techniques in army tactical shelter. The beginning step focuses on developing and identifying different activities and work breakdown structure applicable in shelter prototype. The next step focuses on identifying resource allocation. This include allocate resources based on the delivered project as per alternative one and for the second alternative as optimization, resource allocation modified and tried t… more
Access: Restricted to UNT Community Members. Login required if off-campus.
Date: December 2019
Creator: Yeganehtalab, Babak
open access

Control and Automation of a Heat Shrink Tubing Process

Description: Heat shrink tubing is used to insulate wire conductors, protect wires, and to create cable entry seals in wire harnessing industries. Performing this sensitive process manually is time consuming, the results are strongly dependent on the operator’s expertise, and the process presents safety concerns. Alternatively, automating the process minimizes the operators’ direct interaction, decreases the production cost over the long term, and improves quantitative and qualitative production indicators … more
Date: August 2014
Creator: Yousefi Darani, Shahrokh
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
open access

Cost Savings Realized Through Proper Sizing of an Excessive Instrument Air System.

Description: The purpose of this research was to determine if installing a smaller air compressor could reduce the electrical usage of a large semiconductor manufacturing plant. A 200 horsepower Atlas Copco compressor was installed with the existing 500 horsepower Ingersoll-Rand compressors. Testing was conducted during the regular manufacturing process at MEMC Southwest in Sherman, Texas. Analysis of the data found that installing the new compressor could reduce electrical consumption. The study also found… more
Date: December 2003
Creator: Condron, Ewell D.
open access

A Data Acquisition System Experiment for Gas Temperature and Pressure Measurements on a Liquid-Nitrogen-Powered Vehicle

Description: A data acquisition system was set up to measure gas temperatures and pressures at various points on a liquid-nitrogen-powered vehicle. The experiment was attempted to develop a data acquisition method for applications on engines that use liquid air as the fuel. Two thermocouples and a pressure transducer were connected using data acquisition instruments interfaced to a laptop computer to acquire data.
Date: May 1998
Creator: Lui, Samson Sze-Sang
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
open access

Design and Validation of an Automated Multiunit Composting System.

Description: This thesis covers the design of an automated multiunit composting system (AMUCS) that was constructed to meet the experimental apparatus requirements of the ASTM D5338 standard. The design of the AMUCS is discussed in full detail and validated with two experiments. The first experiment was used to validate the operation of the AMUCS with a 15 day experiment. During this experiment visual observations were made to visually observe degradation. Thermal properties and stability tests were perform… more
Date: December 2009
Creator: Pickens, Mark Everett

Design Method for Cold-Formed Steel Shear Wall Sheathed with Polymer Composite Panel

Description: In order to predict the strength of shear wall with cold-formed steel framing members, analytical models were reviewed. Multiple analytical models were studied, as well as twenty-one connection tests were performed. The connection tests consist of 50-ksi cold-formed steel framing track, different fastening configurations, and different sheathing thicknesses (1/8" and 1/2"). No.12 screw resulted in the highest peak load of all fastening configurations, while the rivet connection had the lowest p… more
Date: August 2020
Creator: Dewaidi, Mohaned Ali

Design Method of Cold-Formed Steel Framed Shear Wall Sheathed by Structural Concrete Panel

Description: The objective of this research is developing a new method of design for cold-formed steel framed shear wall sheathed by ¾" thick USG structural panel concrete subfloor using a predictive analytical model and comparing the results obtained from the model with those achieved from real testing to verify the analytical model and predicted lateral load-carrying capacity resulted from that. Moreover, investigating the impact of various screw spacings on shear wall design parameter such as ultimate st… more
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Date: December 2019
Creator: Ashkanalam, Aida
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
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