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Journal of Undergraduate Research
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MUSC Environmental Biosciences Progress Report
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Analysis of Photonic Networks for a Chip Multiprocessor Using Scientific Applications
As multiprocessors scale to unprecedented numbers of cores in order to sustain performance growth, it is vital that these gains are not nullified by high energy consumption from inter-core communication. With recent advances in 3D Integration CMOS technology, the possibility for realizing hybrid photonic-electronic networks-on-chip warrants investigating real application traces on functionally comparable photonic and electronic network designs. We present a comparative analysis using both synthetic benchmarks as well as real applications, run through detailed cycle accurate models implemented under the OMNeT++ discrete event simulation environment. Results show that when utilizing standard process-to-processor mapping methods, this hybrid network can achieve 75X improvement in energy efficiency for synthetic benchmarks and up to 37X improvement for real scientific applications, defined as network performance per energy spent, over an electronic mesh for large messages across a variety of communication patterns.
Date:
January 31, 2009
Creator:
Kamil, Shoaib A.; Hendry, Gilbert; Biberman, Aleksandr; Chan, Johnnie; Lee, Benjamin G.; Mohiyuddin, Marghoob et al.
Object Type:
Article
System:
The UNT Digital Library
Chemical, Biological, and Explosive Sensors for Field Measurements
Special Technologies Laboratory (STL) is developing handheld chemical, biological, and explosive (CBE) detection systems and sensor motes for wireless networked field operations. The CBE sensors are capable of detecting and identifying multiple targeted toxic industrial chemicals (TICs) and high-explosive vapor components. The CBE devices are based on differential mobility spectrometry (DMS) coupled with fast gas chromatography (GC) or mass spectrometry. The systems all include the concepts of: 1. Direct air/particulate “smart” sampling 2. Selective, continuous real-time (~1 sec) alert monitoring using DMS 3. Highly selective, rapid dual technology separation/verification analysis The biosensor technology is based on Raman aerosol particle flow cytometry for target detection and identification. Monitoring and identifying trace level chemical vapors directly from ambient air will allow First Responders to quickly adapt situational response strategies and personal protective equipment needs to the specific response scenario being encountered. First Responders require great confidence in the measurements and ability of a given system to detect CBE below threshold levels without interferences. The concept of determining the background matrix in near real-time to allow subsequent automated field-programmable method selection and cueing of high-value assets in a wide range of environs will be presented. This provides CBE information for decisions prior to …
Date:
January 31, 2009
Creator:
Kevin Kyle, Manuel Manard, Stephan Weeks
Object Type:
Article
System:
The UNT Digital Library
Conceptual Design Report: Nevada Test Site Mixed Waste Disposal Facility Project
Environmental cleanup of contaminated nuclear weapons manufacturing and test sites generates radioactive waste that must be disposed. Site cleanup activities throughout the U.S. Department of Energy (DOE) complex are projected to continue through 2050. Some of this waste is mixed waste (MW), containing both hazardous and radioactive components. In addition, there is a need for MW disposal from other mission activities. The Waste Management Programmatic Environmental Impact Statement Record of Decision designates the Nevada Test Site (NTS) as a regional MW disposal site. The NTS has a facility that is permitted to dispose of onsite- and offsite-generated MW until November 30, 2010. There is not a DOE waste management facility that is currently permitted to dispose of offsite-generated MW after 2010, jeopardizing the DOE environmental cleanup mission and other MW-generating mission-related activities. A mission needs document (CD-0) has been prepared for a newly permitted MW disposal facility at the NTS that would provide the needed capability to support DOE's environmental cleanup mission and other MW-generating mission-related activities. This report presents a conceptual engineering design for a MW facility that is fully compliant with Resource Conservation and Recovery Act (RCRA) and DOE O 435.1, 'Radioactive Waste Management'. The facility, which will …
Date:
January 31, 2009
Creator:
National Security Technologies, LLC
Object Type:
Report
System:
The UNT Digital Library
The Development of a Rebust Accelerometer-Based Start of Combustion Sensing System
The development of modern combustion systems increasingly relies on detailed knowledge of the combustion event. As the limits of combustion are approached, tight control of combustion leads to improved emissions and higher efficiencies, while retaining and even improving engine reliability and durability. While developing a novel HCCI (Homogeneous Charge Compression Ignition) technology for large natural gas engines, Westport found that there was no reliable cost-effective technology to monitor the combustion event. As a result, Westport began working on developing a solution based on commercially available knock sensors. While initially developed around HCCI, Westport has identified that numerous other forms of combustion (high EGR systems, Homogeneous Charge Direct Injection, etc) will require combustion sensors. This requirement is also reflected in the development of other technologies in this field. However, the potential low system cost and the lack of intrusion into the cylinder head area are significant benefits for the Westport approach. Previous work by Westport has proven the method on two different large compression ignition gas engines. The objective of the current work is to improve the robustness of this technology; particularly, to identify and reduce the sensor-to-sensor and engine-to-engine variations.
Date:
January 31, 2009
Creator:
Huang, Jim & Mumford, David
Object Type:
Report
System:
The UNT Digital Library
Distributed Wind Energy in Idaho
This project is a research and development program aimed at furthering distributed wind technology. In particular, this project addresses some of the barriers to distributed wind energy utilization in Idaho.
Date:
January 31, 2009
Creator:
Gardner, John; Johnson, Kathryn; Haynes, Todd & Seifert, Gary
Object Type:
Report
System:
The UNT Digital Library
A Hydrostratigraphic System for Modeling Groundwater Flow and Radionuclide Migration at the Corrective Action Unit Scale, Nevada Test Site and Surrounding Areas, Clark, Lincoln, and Nye Counties, Nevada
Underground Test Area (UGTA) corrective action unit (CAU) groundwater flow and contaminant transport models of the Nevada Test Site (NTS) and vicinity are built upon hydrostratigraphic framework models (HFMs) that utilize the hydrostratigraphic unit (HSU) as the fundamental modeling component. The delineation and three-dimensional (3-D) modeling of HSUs within the highly complex geologic terrain that is the NTS requires a hydrostratigraphic system that is internally consistent, yet flexible enough to account for overlapping model areas, varied geologic terrain, and the development of multiple alternative HFMs. The UGTA CAU-scale hydrostratigraphic system builds on more than 50 years of geologic and hydrologic work in the NTS region. It includes 76 HSUs developed from nearly 300 stratigraphic units that span more than 570 million years of geologic time, and includes rock units as diverse as marine carbonate and siliciclastic rocks, granitic intrusives, rhyolitic lavas and ash-flow tuffs, and alluvial valley-fill deposits. The UGTA CAU-scale hydrostratigraphic system uses a geology-based approach and two-level classification scheme. The first, or lowest, level of the hydrostratigraphic system is the hydrogeologic unit (HGU). Rocks in a model area are first classified as one of ten HGUs based on the rock’s ability to transmit groundwater (i.e., nature of their …
Date:
January 31, 2009
Creator:
Prothro, Lance; Drellack, Sigmund, Jr. & Mercadante, Jennifer
Object Type:
Report
System:
The UNT Digital Library
MICRO-CHP System for Residential Applications
This is the final report of progress under Phase I of a project to develop and commercialize a micro-CHP system for residential applications that provides electrical power, heating, and cooling for the home. This is the first phase of a three-phase effort in which the residential micro-CHP system will be designed (Phase I), developed and tested in the laboratory (Phase II); and further developed and field tested (Phase III). The project team consists of Advanced Mechanical Technology, Inc. (AMTI), responsible for system design and integration; Marathon Engine Systems, Inc. (MES), responsible for design of the engine-generator subsystem; AO Smith, responsible for design of the thermal storage and water heating subsystems; Trane, a business of American Standard Companies, responsible for design of the HVAC subsystem; and AirXchange, Inc., responsible for design of the mechanical ventilation and dehumidification subsystem.
Date:
January 31, 2009
Creator:
Gerstmann, Joseph
Object Type:
Report
System:
The UNT Digital Library
Nuclear Infrastructure Development: Strategies and Methods for Engaging Nuclear Energy Seeking States
This is the final report for the three infrastructure development workshops PNNL hosted or supported: the two infrastructure development seminars and the Como conference
Date:
January 31, 2009
Creator:
Frazar, Sarah L.; Kessler, Carol A.; Kreyling, Sean J.; Morris, Frederic A.; Mathews, Caroline E.; Bissani, Mo et al.
Object Type:
Report
System:
The UNT Digital Library
Power Systems Development Facility
In support of technology development to utilize coal for efficient, affordable, and environmentally clean power generation, the Power Systems Development Facility (PSDF), located in Wilsonville, Alabama, has routinely demonstrated gasification technologies using various types of coals. The PSDF is an engineering scale demonstration of key features of advanced coal-fired power systems, including a Transport Gasifier, a hot gas particulate control device, advanced syngas cleanup systems, and high-pressure solids handling systems. This final report summarizes the results of the technology development work conducted at the PSDF through January 31, 2009. Twenty-one major gasification test campaigns were completed, for a total of more than 11,000 hours of gasification operation. This operational experience has led to significant advancements in gasification technologies.
Date:
January 31, 2009
Creator:
Southern Company Services
Object Type:
Report
System:
The UNT Digital Library
Preferred orientation of ettringite in concrete fractures
Sulfate attack and the accompanying crystallization of fibrous ettringite [Ca{sub 6}Al{sub 2}(OH){sub 12}(SO{sub 4}){sub 3} {center_dot} 26H{sub 2}O] cause cracking and loss of strength in concrete structures. Hard synchrotron X-ray microdiffraction is used to quantify the orientation distribution of ettringite crystals. Diffraction images are analyzed using the Rietveld method to obtain information on textures. The analysis reveals that the c axes of the trigonal crystallites are preferentially oriented perpendicular to the fracture surfaces. By averaging single-crystal elastic properties over the orientation distribution, it is possible to estimate the elastic anisotropy of ettringite aggregates.
Date:
January 31, 2009
Creator:
Wenk, Hans-Rudolf; Monteiro, Paulo J.M.; Kunz, Martin; Chen, Kai; Tamura, Nobumichi; Lutterotti, Luca et al.
Object Type:
Article
System:
The UNT Digital Library
Production of Substitute Natural Gas from Coal
The goal of this research program was to develop and demonstrate a novel gasification technology to produce substitute natural gas (SNG) from coal. The technology relies on a continuous sequential processing method that differs substantially from the historic methanation or hydro-gasification processing technologies. The thermo-chemistry relies on all the same reactions, but the processing sequences are different. The proposed concept is appropriate for western sub-bituminous coals, which tend to be composed of about half fixed carbon and about half volatile matter (dry ash-free basis). In the most general terms the process requires four steps (1) separating the fixed carbon from the volatile matter (pyrolysis); (2) converting the volatile fraction into syngas (reforming); (3) reacting the syngas with heated carbon to make methane-rich fuel gas (methanation and hydro-gasification); and (4) generating process heat by combusting residual char (combustion). A key feature of this technology is that no oxygen plant is needed for char combustion.
Date:
January 31, 2009
Creator:
Lucero, Andrew
Object Type:
Report
System:
The UNT Digital Library
Reducing the Vulnerability of Electric Power Grids to Terrorist Attacks
This report describes the development of a cascading outage analyzer that, given an initial disturbance on an electric power system, checks for thermal overloads, under-frequency and over-frequency conditions, and under-voltage conditions that would result in removal of elements from the system. The analyzer simulates the successive tripping of elements due to protective actions until a post-event steady state or a system blackout is reached.
Date:
January 31, 2009
Creator:
Baldick, Ross; Boutsika, Thekla; Hur, Jin; Joung, Manho; Wu, Yin & Zhong, Minqi
Object Type:
Report
System:
The UNT Digital Library
Regional Effort to Deploy Clean Coal Technologies
The Southern States Energy Board's (SSEB) 'Regional Effort to Deploy Clean Coal Technologies' program began on June 1, 2003, and was completed on January 31, 2009. The project proved beneficial in providing state decision-makers with information that assisted them in removing barriers or implementing incentives to deploy clean coal technologies. This was accomplished through two specific tasks: (1) domestic energy security and diversity; and (2) the energy-water interface. Milestones accomplished during the project period are: (1) Presentations to Annual Meetings of SSEB Members, Associate Member Meetings, and the Gasification Technologies Council. (2) Energy: Water reports - (A) Regional Efforts to Deploy Clean Coal Technologies: Impacts and Implications for Water Supply and Quality. June 2004. (B) Energy-Water Interface Challenges: Coal Bed Methane and Mine Pool Water Characterization in the Southern States Region. 2004. (C) Freshwater Availability and Constraints on Thermoelectric Power Generation in the Southeast U.S. June 2008. (3) Blackwater Interactive Tabletop Exercise - Decatur, Georgia April 2007. (4) Blackwater Report: Blackwater: Energy and Water Interdependency Issues: Best Practices and Lessons Learned. August 2007. (5) Blackwater Report: BLACKWATER: Energy Water Interdependency Issues REPORT SUMMARY. April 2008.
Date:
January 31, 2009
Creator:
Hill, Gerald; Nemeth, Kenneth; Garrett, Gary & Sams, Kimberly
Object Type:
Report
System:
The UNT Digital Library
The Role of Natural Organic Matter and Mineral Colloids in the Transport of Contaminants through Heterogeneous Vadose-Zone Environments
Our research was guided by a key objective of the Environmental Management Science Program (EMSP), which is to improve conceptual and predictive models for contaminant movement in complex vadose zone environments. In this report, increases in the understanding of colloidcontaminant interactions, colloid mobilization, and colloid deposition within unsaturated soils are cited as requisite needs for predicting contaminant fate and distribution in the vadose zone. We addressed these needs by pursuing three key goals: 1. Identify the mechanisms that govern OM and mineral-colloid reaction and transport in heterogeneous, unsaturated porous media; 2. Quantify the role of OM and mineral colloids in scavenging and facilitating the transport of contaminants of concern to DOE; and 3. Develop and test a mathematical model suitable for simulating the movement of OM- and colloid-associated contaminants through heterogeneous, unsaturated porous media.
Date:
January 31, 2009
Creator:
Saiers, James & Ryan, Joseph
Object Type:
Report
System:
The UNT Digital Library
Thenature of marbled Terra Sigillata slips: a combined mu XRF and mu XRD investigation
In addition to the red terra sigillata production, the largest Gallic workshop (La Graufesenque) made a special type of terra sigillata, called 'marbled' by the archaeologists. Produced exclusively on this site, this pottery is characterized by a surface finish made of a mixture of yellow and red slips. Because the two slips are intimately mixed, it is difficult to obtain the precise composition of one of the two constituents without contamination by the other. In order to obtain very precise correlation at the appropriate scale between the color aspect and the element and mineralogical phase distributions in the slip, combined electron microprobe, x-ray micro spectroscopies and micro diffraction on cross sectional samples were performed. The aim is to discover how potters were able to produce this unique type of terra sigillata and especially this slip showing an intense yellow color. Results show that the yellow component of marbled sigillata was made from a titanium-rich clay preparation. The color is related to the formation of a pseudobrookite (TiFe2O5) phase in the yellow part of the slip, the main characteristics of that structure being considered nowadays as essential for the fabrication of stable yellow ceramic pigments. Its physical properties such as high …
Date:
January 31, 2009
Creator:
Leon, Yoanna; Sciau, Philippe; Goudeau, Philippe; Tamura, Nobumichi; Webb, Sam & Mehta, Apurva
Object Type:
Article
System:
The UNT Digital Library
Theoretical Studies of Nucleation Kinetics and Nanodroplet Microstructure
The goals of this project were to (1) explore ways of bridging the gap between fundamental molecular nucleation theories and phenomenological approaches based on thermodynamic reasoning, (2) test and improve binary nucleation theory, and (3) provide the theoretical underpinning for a powerful new experimental technique, small angle neutron scattering (SANS) from nanodroplet aerosols, that can probe the compositional structure of nanodroplets. This report summarizes the accomplishments of this project in realizing these goals. Publications supported by this project fall into three general categories: (1) theoretical work on nucleation theory (2) experiments and modeling of nucleation and condensation in supersonic nozzles, and (3) experimental and theoretical work on nanodroplet structure and neutron scattering. These publications are listed and briefly summarized in this report.
Date:
January 31, 2009
Creator:
Wilemski, Gerald
Object Type:
Report
System:
The UNT Digital Library
ALARA ASSESSMENT OF SETTLER SLUDGE SAMPLING METHODS
The purpose of this assessment is to compare underwater and above water settler sludge sampling methods to determine if the added cost for underwater sampling for the sole purpose of worker dose reductions is justified. Initial planning for sludge sampling included container, settler and knock-out-pot (KOP) sampling. Due to the significantly higher dose consequence of KOP sludge, a decision was made to sample KOP underwater to achieve worker dose reductions. Additionally, initial plans were to utilize the underwater sampling apparatus for settler sludge. Since there are no longer plans to sample KOP sludge, the decision for underwater sampling for settler sludge needs to be revisited. The present sampling plan calls for spending an estimated $2,500,000 to design and construct a new underwater sampling system (per A21 C-PL-001 RevOE). This evaluation will compare and contrast the present method of above water sampling to the underwater method that is planned by the Sludge Treatment Project (STP) and determine if settler samples can be taken using the existing sampling cart (with potentially minor modifications) while maintaining doses to workers As Low As Reasonably Achievable (ALARA) and eliminate the need for costly redesigns, testing and personnel retraining.
Date:
January 30, 2009
Creator:
LA, NELSEN
Object Type:
Report
System:
The UNT Digital Library
Assessment of the Environmental Impacts of Coalbed Methane Development in the Powder River Basin - Use of Coalbead Methane Produced Water for Cropland Irrigation
Water quality is a major concern with regard to development of coalbed methane (CBM) in the Powder River Basin, Wyoming. Large quantities of water are being produced and discharged as a by-product in the process of releasing natural gas from coal. Current practices of discharging large volumes of water into drainage channels or using it to irrigate cropland areas has the potential to elevate salinity and sodicity in soils. Elevated salinity affects the ability of plants to uptake water to facilitate biochemical processes such as photosynthesis and plant growth. Elevated sodicity in irrigation water adversely affects soil structure necessary for water infiltration, nutrient supply, and aeration. Salinity and sodicity concentrations are important in that a sodic soil can maintain its structure if the salinity level is maintained above the threshold electrolyte concentration. In this study, cropland soil and CBM water were treated with gypsum and sulfur. Changes in soil chemistry among different treatments were monitored using a split plot experiment. The CBM water used for irrigation had an EC of 1380 {micro}S cm{sup -1} and SAR of 24.3 mmol{sup 1/2} L{sup -1/2}. Baseline and post treatment soil samples were collected to a depth of 60 cm within each study plot, …
Date:
January 30, 2009
Creator:
Morris, Jeff
Object Type:
Report
System:
The UNT Digital Library
Consumptive water use in the production of ethanonl and petroleum gasoline.
The production of energy feedstocks and fuels requires substantial water input. Not only do biofuel feedstocks like corn, switchgrass, and agricultural residues need water for growth and conversion to ethanol, but petroleum feedstocks like crude oil and oil sands also require large volumes of water for drilling, extraction, and conversion into petroleum products. Moreover, in many cases, crude oil production is increasingly water dependent. Competing uses strain available water resources and raise the specter of resource depletion and environmental degradation. Water management has become a key feature of existing projects and a potential issue in new ones. This report examines the growing issue of water use in energy production by characterizing current consumptive water use in liquid fuel production. As used throughout this report, 'consumptive water use' is the sum total of water input less water output that is recycled and reused for the process. The estimate applies to surface and groundwater sources for irrigation but does not include precipitation. Water requirements are evaluated for five fuel pathways: bioethanol from corn, ethanol from cellulosic feedstocks, gasoline from Canadian oil sands, Saudi Arabian crude, and U.S. conventional crude from onshore wells. Regional variations and historic trends are noted, as are opportunities …
Date:
January 30, 2009
Creator:
Wu, M.; Mintz, M.; Wang, M.; Arora, S. & Systems, Energy
Object Type:
Report
System:
The UNT Digital Library
DNA Probe Pooling for Rapid Delineation of Chromosomal Breakpoints
Structural chromosome aberrations are hallmarks of many human genetic diseases. The precise mapping of translocation breakpoints in tumors is important for identification of genes with altered levels of expression, prediction of tumor progression, therapy response, or length of disease-free survival as well as the preparation of probes for detection of tumor cells in peripheral blood. Similarly, in vitro fertilization (IVF) and preimplantation genetic diagnosis (PGD) for carriers of balanced, reciprocal translocations benefit from accurate breakpoint maps in the preparation of patient-specific DNA probes followed by a selection of normal or balanced oocytes or embryos. We expedited the process of breakpoint mapping and preparation of case-specific probes by utilizing physically mapped bacterial artificial chromosome (BAC) clones. Historically, breakpoint mapping is based on the definition of the smallest interval between proximal and distal probes. Thus, many of the DNA probes prepared for multi-clone and multi-color mapping experiments do not generate additional information. Our pooling protocol described here with examples from thyroid cancer research and PGD accelerates the delineation of translocation breakpoints without sacrificing resolution. The turnaround time from clone selection to mapping results using tumor or IVF patient samples can be as short as three to four days.
Date:
January 30, 2009
Creator:
Lu, Chun-Mei; Kwan, Johnson; Baumgartner, Adolf; Weier, Jingly F.; Wang, Mei; Escudero, Tomas et al.
Object Type:
Report
System:
The UNT Digital Library
Eastern Band of Cherokee Strategic Energy Plan
The Eastern Band of Cherokee Indians was awarded a grant under the U.S. Department of Energy Tribal Energy Program (TEP) to develop a Tribal Strategic Energy Plan (SEP). The grant, awarded under the “First Steps” phase of the TEP, supported the development of a SEP that integrates with the Tribe’s plans for economic development, preservation of natural resources and the environment, and perpetuation of Tribal heritage and culture. The Tribe formed an Energy Committee consisting of members from various departments within the Tribal government. This committee, together with its consultant, the South Carolina Institute for Energy Studies, performed the following activities: • Develop the Tribe’s energy goals and objectives • Establish the Tribe’s current energy usage • Identify available renewable energy and energy efficiency options • Assess the available options versus the goals and objectives • Create an action plan for the selected options
Date:
January 30, 2009
Creator:
Leitner, Souther Carolina Institute of energy Studies-Robert
Object Type:
Report
System:
The UNT Digital Library
Electron exchange-correlation in quantum mechanics
It is shown that Fermi-Dirac statistics is guaranteed by the Dirac current, from which spin-dependent quantum velocity fields and spin-dependent quantum trajectories can be inferred. Pauli's exclusion principle is demonstrated using the spin-dependent quantum trajectories. The Dirac current, unlike the Schroedinger current, is nonzero for stationary bound states due to the permanent magnetic moment of the electron. It is of order c{sup 0} in agreement with observation that Fermi-Dirac statistics is independent of electronic velocity. In summary the physical basis for exchange-correlation is found in Dirac's equation, although Schroedinger's equation may be used to evaluate the Dirac current in the nonrelativistic regime of electronic velocity.
Date:
January 30, 2009
Creator:
Ritchie, Burke
Object Type:
Article
System:
The UNT Digital Library
Environmental Biosciences Program Quarterly Report
Current research projects have focused Environmental Biosciences Program (EBP) talent and resources on providing the scientific basis for risk-based standards, risk-based decision making and the accelerated clean-up of widespread environmental hazards. These hazards include trichloroethylene, low-dose ionizing radiation (gamma and neutron) and alpha radiation from plutonium. Trichloroethylene research has been conducted as a joint collaborative effort with the University of Georgia. Work on the trichloroethylene research projects has been slowed as a result of funding uncertainties. The impact of these funding uncertainties has been discussed with the United States Department of Energy (DOE). Laboratory work has been completed on several trichloroethylene risk assessment projects, and these projects have been brought to a close. Plans for restructuring the performance schedule of the remaining trichloroethylene projects have been submitted to the department. A comprehensive manuscript on the scientific basis of trichloroethylene risk assessment is in preparation. Work on the low-dose radiation risk assessment projects is also progressing at a slowed rate as a result of funding uncertainties. It has been necessary to restructure the proponency and performance schedule of these projects, with the project on Low-Dose Radiation: Epidemiology Risk Models transferred to DOE Office of Science proponency under a separate funding instrument. …
Date:
January 30, 2009
Creator:
Mohr, Lawrence C.
Object Type:
Report
System:
The UNT Digital Library
Evidence for residual elastic strain in deformed natural quartz
Residual elastic strain in naturally deformed, quartz-containing rocks can be measured quantitatively in a petrographic thin section with high spatial resolution using Laue microdiffraction with white synchrotron x-rays. The measurements with a resolution of one micrometer allow the quantitative determination of the deviatoric strain tensor as a function of position within the crystal investigated. The observed equivalent strain values of 800-1200 microstrains represent a lower bound of the actual preserved residual strain in the rock, since the stress component perpendicular to the cut sample surface plane is released. The measured equivalent strain translates into an equivalent stress in the order of {approx} 50 MPa.
Date:
January 30, 2009
Creator:
Kunz, Martin; Chen, Kai; Tamura,Nobumichi & Wenk, Hans-Rudolf
Object Type:
Article
System:
The UNT Digital Library