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Methods for Analyzing Electric Load Shape and its Variability

Description: Current methods of summarizing and analyzing electric load shape are discussed briefly and compared. Simple rules of thumb for graphical display of load shapes are suggested. We propose a set of parameters that quantitatively describe the load shape in many buildings. Using the example of a linear regression model to predict load shape from time and temperature, we show how quantities such as the load?s sensitivity to outdoor temperature, and the effectiveness of demand response (DR), can be qu… more
Date: May 12, 2010
Creator: Price, Philip
Partner: UNT Libraries Government Documents Department
open access

Shape trends and triaxiality in neutron-rich odd-mass Y and Nbisotopes

Description: New level schemes of Y and Nb isotopes are proposed based on measurements of prompt gamma rays from 252Cf fission at Gammasphere. Shape trends regarding triaxiality and quadrupole deformations are studied.
Date: September 28, 2004
Creator: Luo, Y. X.; Rasmussen, J. O.; Gelberg, A.; Stefanescu, I.; Hamilton, J. H.; Ramayya, A. V. et al.
Partner: UNT Libraries Government Documents Department

Processing and Shape-Setting of Shape Memory Alloys for Small Satellite Antennas

Description: In this study, four different NiTi-based shape memory alloys (SMAs) compositions were processed, shape-set, and characterized to evaluate their effectiveness as SMA actuation component for satellite antennas. Three of the compositions were commercially available NiTi wires (90°C Flexinol® actuator NiTi wire and Confluent ADB SE508 NiTi wire), NiTi SM495 plates (ATI Specialty Alloys and Components) and the other composition was in house lab-produced NiTiCu plate. Different shape-setting techniqu… more
Date: December 2022
Creator: Al Jabri, Nehal Ahmed Mubarak
Partner: UNT Libraries
open access

A Bayesian Approach for Image Segmentation with Shape Priors

Description: Color and texture have been widely used in image segmentation; however, their performance is often hindered by scene ambiguities, overlapping objects, or missingparts. In this paper, we propose an interactive image segmentation approach with shape prior models within a Bayesian framework. Interactive features, through mouse strokes, reduce ambiguities, and the incorporation of shape priors enhances quality of the segmentation where color and/or texture are not solely adequate. The novelties of … more
Date: June 20, 2008
Creator: Chang, Hang; Yang, Qing & Parvin, Bahram
Partner: UNT Libraries Government Documents Department
open access

Characterization of shape memory alloys for safety mechanisms.

Description: Shape memory alloys (SMAs) are metals that exhibit large recoverable strains and exert large forces with tremendous energy densities. The behavior of SMAs is thermomechanically coupled. Their response to temperature is sensitive to their loading condition and their response to loading is sensitive to their thermal condition. This coupled behavior is not to be circumvented, but to be confronted and understood, since it is what manifests SMA's superior clamping performance. To reasonably characte… more
Date: March 1, 2008
Creator: McLaughlin, Jarred T.; Buchheit, Thomas Edward & Massad, Jordan Elias
Partner: UNT Libraries Government Documents Department
open access

Influence of High Strain Rate Compression on Microstructure and Phase Transformation of NiTi Shape Memory Alloys

Description: Since NiTi shape memory alloy (SMA) was discovered in the early 1960s, great progress has been made in understanding the properties and mechanisms of NiTi SMA and in developing associated products. For several decades, most of the scientific research and industrial interests on NiTi SMA has focused on its superelastic applications in the biomedical field and shape memory based “smart” devices, which involves the low strain rate (around 0.001 s^-1) response of NiTi SMA. Due to either stress-indu… more
Date: May 2016
Creator: Qiu, Ying
Partner: UNT Libraries
open access

Final Technical Report: Nanostructured Shape Memory Alloys

Description: With this grant we explored the properties that result from combining the effects of nanostructuring and shape memory using both experimental and theoretical approaches. We developed new methods to make nanostructured NiTi by melt-spinning and cold rolling fabrication strategies, which elicited significantly different behavior. A template synthesis method was also used to created nanoparticles. In order to characterize the particles we created, we developed a new magnetically-assisted particle … more
Date: July 28, 2005
Creator: Crone, Wendy; Drugan, Walter; Ellis, Arthur & Perepezko, John
Partner: UNT Libraries Government Documents Department
open access

Perceived Attractiveness and Personality Attributes: A Gender and Racial Analysis

Description: Subjects rated 12 female body shapes with respect to their physical attractiveness, and the extent to which they would be expected to possess various personality characteristics. The shapes were varied using 3 levels of overall weight and 4 levels of body shapeliness. The sample was modified to control for socioeconomic factors and results are based on 297 undergraduates from Caucasian, African American, and Hispanic racial backgrounds. Loglinear analyses revealed that men and women, regardles… more
Date: May 2000
Creator: Olby, Brian C.
Partner: UNT Libraries
open access

Final Report: FG02-01ER-45906 - A novel class of artificially modulated magnetic multilayers based on magnetic shape memory alloys

Description: The temperature dependent micromagnetic behavior, structural phase transitions, magnetic transition, and the dynamics of phase transitions have been investigated using magnetic shape memory alloys. Results provide a novel concept of ‘polymagnets’. In thin film form the number of martensite variants is greatly reduced. A new technique to study dynamics of magnetic phase transitions has been developed applicable to bulk, thin films or multilayers. Transition pathways in magnetic shape memory al… more
Date: June 20, 2005
Creator: Chopra, H. D.
Partner: UNT Libraries Government Documents Department
open access

Thermomechanical characterization of nickel-titanium-copper shape memory alloy films

Description: In an effort to develop a more extensive model for the thermomechanical behavior of shape memory alloy (SMA) films, a novel characterization method has been developed. This automated test has been tailored to characterize films for use in micro-electromechanical system (MEMS) actuators. The shape memory effect in NiTiCu is seen in the solid-state phase transformation from an easily deformable low-temperature state to a 'shape remembering' high-temperature state. The accurate determination of en… more
Date: October 31, 2000
Creator: Seward, K P; Ramsey, P B & Krulevitch, P
Partner: UNT Libraries Government Documents Department
open access

A new mechanical characterization method for thin film microactuators and its application to NiTiCi shape memory alloy

Description: In an effort to develop a more full characterization tool of shape memory alloys, a new technique is presented for the mechanical characterization of microactuators and applied to SMA thin films. A test instrument was designed to utilize a spring-loaded transducer in measuring displacements with resolution of 1.5 pm and forces with resolution of 0.2 mN. Employing an out-of-plane loading method for freestanding SMA thin films, strain resolution of 30{mu}{epsilon} and stress resolution of 2.5 MPa… more
Date: June 1, 1999
Creator: Seward, K P
Partner: UNT Libraries Government Documents Department
open access

Thermo-Mechanical Processing and Advanced Charecterization of NiTi and NiTiHf Shape Memory Alloys

Description: Shape memory alloys (SMAs) represent a revolutionary class of active materials that can spontaneously generate strain based on an environmental input, such as temperature or stress. SMAs can provide potential solutions to many of today's engineering problems due to their compact form, high energy densities, and multifunctional capabilities. While many applications in the biomedical, aerospace, automotive, and defense industries have already been investigated and realized for nickel-titanium (Ni… more
Date: May 2020
Creator: Ley, Nathan A
Partner: UNT Libraries
open access

Sub-10 nm Platinum Nanocrystals with Size and Shape Control: Catalytic Study for Ethylene and Pyrrole Hydrogenation

Description: Platinum nanocubes and nanopolyhedra with tunable size from 5 to 9 nm were synthesized by controlling the reducing rate of metal precursor ions in a one-pot polyol synthesis. A two-stage process is proposed for the simultaneous control of size and shape. In the first stage, the oxidation state of the metal ion precursors determined the nucleation rate and consequently the number of nuclei. The reaction temperature controlled the shape in the second stage by regulation of the growth kinetics. Th… more
Date: March 2, 2009
Creator: Tsung, Chia-Kuang; Kuhn, John N.; Huang, Wenyu; Aliaga, Cesar; Hung, Ling-I; Somorjai, Gabor A. et al.
Partner: UNT Libraries Government Documents Department
open access

Synchrotron Radiation X-Ray Diffraction of Nickel-Titanium Shape Memory Alloy Wires During Mechanical Deformation

Description: Shape memory alloys (SMAs) are a new generation material which exhibits unique nonlinear deformations due to a phase transformation which allows it to return to its original shape after removal of stress or a change in temperature. It shows a shape memory effect (martensitic condition) and pseudoelasticity (austenitic condition) properties depends on various heat treatment conditions. The reason for these properties depends on phase transformation through temperature changes or applied stress. … more
Date: December 2015
Creator: Zhang, Baozhuo
Partner: UNT Libraries
open access

The effect of temporal pulse shape on optical damage

Description: The conditions under which optical materials are susceptible to laser-induced damage is a topic which has been the subject of considerable study. Laser parameters such as wavelength and temporal pulse duration have been studied extensively. Until this work the effect of temporal pulse shape has not been considered. We present here data from a simple single-parameter model and a supporting experiment which predicts that a Flat-In-Time-pulse will produce damage at approximately 80% of the fluence… more
Date: August 15, 2006
Creator: Carr, C W; Trenholme, J B & Spaeth, M L
Partner: UNT Libraries Government Documents Department
open access

The Investigation of Illusionary Space on Dark Surfaces Using Elliptical and Spherical Shapes

Description: The problem was to investigate illusionary space as affected by dark surfaces using the elliptical and spherical shapes from previous work. I explored the potential of visual tension, movement, pattern, and various degrees of space on surfaces of opposite tonalities from those previously used. An investigation of space on dark surfaces was undertaken and ten works completed.
Date: May 1977
Creator: Moseley, George W.
Partner: UNT Libraries
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