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Quantitative Analysis in Kinesiology

Description: This poster discusses the experiential learning activities developed for the UNT Quantitative Analysis in Kinesiology course, including technology components, video segments created, fully functional learning modules, flash learning activities, and integrated clicker technology.
Date: March 28, 2012
Creator: Budnar, Ronald & Morrow, James R.
Partner: UNT College of Education

Enhancing student-centered learning in Biomechanics (KINE3050) using new and emerging technological educational tools

Description: Poster presented as part of the 2012 University Forum on Teaching & Learning at UNT. This poster describes a a project for a course using new and emerging technological educational tools. This project redesigned KINE-3050 (Biomechanics) as a blended course with the aim to enhance student-centered learning.
Date: March 28, 2012
Creator: Vingren, Jakob L.
Partner: UNT College of Education

Results of IEC 62804 Draft Round Robin Testing (Presentation)

Description: Three crystalline silicon module designs were distributed in five replicas each to five laboratories for testing according to the IEC 62804 (Committee Draft) system voltage durability qualification test for crystalline silicon photovoltaic (PV) modules. The stress tests were performed in environmental chambers at 60 degrees C, 85% relative humidity, 96 h, and with module nameplate system voltage applied.
Date: September 1, 2013
Creator: Hacke, P.; Terwilliger, K.; Koch, S.; Weber, T.; Berghold, J.; Hoffmann, S. et al.
Partner: UNT Libraries Government Documents Department

Almost Holomorphic Poincaré Series Corresponding to Products of Harmonic Siegel–Maass Forms

Description: This article investigates Poincaré series, particularly the study of Siegel–Poincaré series of degree 2 attached to products of terms of Fourier series of harmonic Siegel–Maass forms and holomorphic Siegel modular forms
Date: April 15, 2016
Creator: Bringmann, Kathrin; Richter, Olav K. & Westerholt-Raum, Martin
Partner: UNT College of Arts and Sciences

Equivalence Classes of Subquotients of Pseudodifferential Operator Modules on the Line

Description: Certain subquotients of Vec(R)-modules of pseudodifferential operators from one tensor density module to another are categorized, giving necessary and sufficient conditions under which two such subquotients are equivalent as Vec(R)-representations. These subquotients split under the projective subalgebra, a copy of ????2, when the members of their composition series have distinct Casimir eigenvalues. Results were obtained using the explicit description of the action of Vec(R) with respect to this splitting. In the length five case, the equivalence classes of the subquotients are determined by two invariants. In an appropriate coordinate system, the level curves of one of these invariants are a pencil of conics, and those of the other are a pencil of cubics.
Date: August 2012
Creator: Larsen, Jeannette M.
Partner: UNT Libraries

Properties of R-Modules

Description: This thesis investigates some of the properties of R-modules. The material is presented in three chapters. Definitions and theorems which are assumed are stated in Chapter I. Proofs of these theorems may be found in Zariski and Samuel, Commutative Algebra, Vol. I, 1958. It is assumed that the reader is familiar with the basic properties of commutative rings and ideals in rings. Properties of R-modules are developed in Chapter II. The most important results presented in this chapter include existence theorems for R-modules and properties of submodules in R-modules. The third and final chapter presents an example which illustrates how a ring R, may be regarded as an R-module and speaks of the direct sum of ideals of a ring as a direct sum of submodules.
Date: August 1989
Creator: Granger, Ginger Thibodeaux
Partner: UNT Libraries

Framework for a Comparative Accelerated Testing Standard for PV Modules: Preprint

Description: As the photovoltaic industry has grown, the interest in comparative accelerated testing has also grown. Private test labs offer testing services that apply greater stress than the standard qualification tests as tools for differentiating products and for gaining increased confidence in long-term PV investments. While the value of a single international standard for comparative accelerated testing is widely acknowledged, the development of a consensus is difficult. This paper strives to identify a technical basis for a comparative standard.
Date: August 1, 2013
Creator: Kurtz, S.; Wohlgemuth, J.; Yamamichi, M.; Sample, T.; Miller, D.; Meakin, D. et al.
Partner: UNT Libraries Government Documents Department

Challenge to Move from 'One Size Fits All' to PV Modules the Customer Needs: Preprint

Description: Historically, PV companies requested a single qualification test for a single product. As the market has grown, there have been increasing opportunities for companies to differentiate their products while still maintaining high manufacturing volumes of each product. At the same time, as PV is deployed in an increasingly broad range of conditions, modules need to be able to withstand a wide range of stresses. In some cases, targeting a specific deployment condition may allow reduction of product cost. Realizing this opportunity will require the ability to confidently predict long-term performance based on accelerated tests and known weather conditions. By working together, the community can most quickly develop tests that identify which products perform well under which conditions. This paper discusses some of the challenges of predicting long-term PV performance, including the wide range of stresses that may be encountered, the variability of the stresses from moment to moment, the complexity of some degradation mechanisms, and the dependence of accelerated testing on module geometry. The paper also describes two international projects that deal with location-specific durability evaluation and long-term module performance.
Date: September 1, 2011
Creator: Kurtz, S.; Wohlgemuth, J.; Hacke, P.; Bosco, N.; Kempe, M.; Smith, R. et al.
Partner: UNT Libraries Government Documents Department

Photovoltaic Degradation Rates -- An Analytical Review

Description: As photovoltaic penetration of the power grid increases, accurate predictions of return on investment require accurate prediction of decreased power output over time. Degradation rates must be known in order to predict power delivery. This article reviews degradation rates of flat-plate terrestrial modules and systems reported in published literature from field testing throughout the last 40 years. Nearly 2000 degradation rates, measured on individual modules or entire systems, have been assembled from the literature, showing a median value of 0.5%/year. The review consists of three parts: a brief historical outline, an analytical summary of degradation rates, and a detailed bibliography partitioned by technology.
Date: June 1, 2012
Creator: Jordan, D. C. & Kurtz, S. R.
Partner: UNT Libraries Government Documents Department

Conservation of Modules but not Phenotype in Bacterial Response to Environmental Stress

Description: Microbes live in changing environments and change their phenotype via gene regulation in response. Although this transcriptional response is important for fitness, very little is known about how it evolves in microbes. We started by asking a number of high-level questions about the evolution of transcriptional phenotype: (1) To what extent is transcriptional response conserved, i.e. do conserved genes respond similarly to the same condition; (2) To what extent are transcriptional modules conserved; and (3) Does there exist a general stress response to a variety of stressors? To illuminate these questions, we analyzed more than 500 microarray experiments across the bacterial domain. We looked for conservation of transcriptional regulation both in close sister species and vastly divergent clades. In addition, we produced and analyzed an extensive in-house compendium of environmental stress data in three metal-reducing bacteria.
Date: May 17, 2010
Creator: Timberlake, Sonia; Joachimiak, Marcin; Joyner, Dominique; Chakraborty, Romy; Baumohl, Jason; Dehal, Paramvir et al.
Partner: UNT Libraries Government Documents Department

Timer modules for radiation detection systems

Description: In developing radiation detection instrumentation at Rocky Flats, a system concept using plug-in modules was planned. Losses of operational time due to maintenance are drastically reduced as a malfunctioning module can be replaced within minutes. Versatility is another advantage of the modular concept and a particular module can be used in many different system designs. A significant cost savings in system development can also be realized. Two of the timers described are housed in two-wide Nuclear Instrumentation Bin (NIM-BIN) modules and a third model in a one-wide NIM-BIN module. The design uses the latest COS/ MOS (complimentary symmetry metal-oxide semiconductor) integrated circuitry, featuring low power, low cost, and high reliability. These modules were developed specifically for radiation detection systems. Model 24370-21 is used in gross alpha detection systems. Model 27213-21 appears in a medical wound- counter system and the third, Model 27213-23, operates in a gamma spectrometer system. These modules can have application in other related systems as well. Operational procedures and servicing are included. (auth)
Date: March 29, 1974
Creator: Martin, B. E.
Partner: UNT Libraries Government Documents Department

The Carboxysome and Other Bacterial Microcompartments

Description: - Carboxysomes are part of the carbon concentrating mechanism in cyanobacteria and chemoautotrophs. - Carboxysomes are a subclass of bacterial microcompartments (BMCs); BMCs can encapsulate a range of metabolic processes. - Like some viral particles, the carboxysome can be modeled as an icosahedron-in its case, having 4,000-5,000 hexameric shell subunits and 12 surface pentamers to generate curvature. - The threefold axis of symmetry of the CsoS1D protein in carboxysomes forms a pore that can open and close, allowing for selective diffusion. - Genetic modules encoding BMC shell proteins and the enzymes that they encapsulate are horizontally transferable, suggesting they enable bacteria to adapt to diverse environments.
Date: June 23, 2010
Creator: Kerfeld, Cheryl A.; Greenleaf, William B. & Kinney, James N.
Partner: UNT Libraries Government Documents Department

Outdoor performance stability and controlled light-soak testing of amorphous silicon multijunction modules at NREL

Description: The National Renewable Energy Laboratory (NREL) has been testing amorphous silicon (a-Si) Photovoltaic (PV) modules for more than a decade. NREL has been conducting controlled light-soak testing of multifunction a-Si modules to characterize their performance for stability evaluation as well as to benchmark the technology status. Some of the test modules, after controlled light-soak testing, have been installed outdoors. The authors have observed that under outdoor exposure, the modules further degrade in performance, possibly due to lower outdoor temperatures and varying spectra. The paper presents data on the light-induced degradation for the third controlled light-soak test on multijunction a-Si modules as well as outdoor performance data on single and multijunction modules under prevailing conditions.
Date: October 1, 1995
Creator: Mrig, L.; Burdick, J.; Luft, W. & Kroposki, B.
Partner: UNT Libraries Government Documents Department

Photovoltaic module energy rating methodology development

Description: A consensus-based methodology to calculate the energy output of a PV module will be described in this paper. The methodology develops a simple measure of PV module performance that provides for a realistic estimate of how a module will perform in specific applications. The approach makes use of the weather data profiles that describe conditions throughout the US and emphasizes performance differences between various module types. An industry-representative Technical Review Committee has been assembled to provide feedback and guidance on the strawman and final approach used in developing the methodology.
Date: May 1996
Creator: Kroposki, B.; Myers, D.; Emery, K.; Mrig, L.; Whitaker, C. & Newmiller, J.
Partner: UNT Libraries Government Documents Department

Development of a Visual Inspection Checklist for Evaluation of Fielded PV Module Condition (Presentation)

Description: A visual inspection checklist for the evaluation of fielded photovoltaic (PV) modules has been developed to facilitate collection of data describing the field performance of PV modules. The proposed inspection checklist consists of 14 sections, each documenting the appearance or properties of a part of the module. This tool has been evaluated through the inspection of over 60 PV modules produced by more than 20 manufacturers and fielded at two different sites for varying periods of time. Aggregated data from a single data collection tool such as this checklist has the potential to enable longitudinal studies of module condition over time, technology evolution, and field location for the enhancement of module reliability models.
Date: March 1, 2012
Creator: Packard, C. E; Wohlgemuth, J. H. & Kurtz, S. R.
Partner: UNT Libraries Government Documents Department

Group 3: Humidity, Temperature and Voltage (Presentation)

Description: This is a summary of the work of Group 3 of the International PV QA Task Force. Group 3 is chartered to develop accelerated stress tests that can be used as comparative predictors of module lifetime versus stresses associated with humidity, temperature and voltage.
Date: September 1, 2013
Creator: Wohlgemuth, J.
Partner: UNT Libraries Government Documents Department

Module Technology: Current Practice and Issues (Presentation)

Description: PV modules must provide mechanical support for the cells, protect the world from the voltages inside, protect the cells, diodes and interconnects from the weather outside, couple as much light as possible into the PV cells and minimize the temperature increase of the cells. The package must continue to serve these functions for at least 25 years as that is the typical module warranty period today. Furthermore the package must do all this for as low a cost as possible since the key to large scale PV growth is a reduction in cost while retaining excellent module reliability and durability. This paper will review current module construction practices for both crystalline silicon and thin film PV with emphasis on explaining why the present designs and materials have been selected. Possible long term issues with today's designs and materials will be discussed. Several proposed solutions to these issues will be presented, highlighting the research efforts that will be necessary in order to verify that they can cost effectively solve the identified issues.
Date: October 5, 2010
Creator: Wohlgemuth, J.
Partner: UNT Libraries Government Documents Department

Advanced Fuel Cycle Cost Basis

Description: This report, commissioned by the U.S. Department of Energy (DOE), provides a comprehensive set of cost data supporting a cost analysis for the relative economic comparison of options for use in the Advanced Fuel Cycle Initiative (AFCI) Program. The report describes the AFCI cost basis development process, reference information on AFCI cost modules, a procedure for estimating fuel cycle costs, economic evaluation guidelines, and a discussion on the integration of cost data into economic computer models. This report contains reference cost data for 25 cost modules—23 fuel cycle cost modules and 2 reactor modules. The cost modules were developed in the areas of natural uranium mining and milling, conversion, enrichment, depleted uranium disposition, fuel fabrication, interim spent fuel storage, reprocessing, waste conditioning, spent nuclear fuel (SNF) packaging, long-term monitored retrievable storage, near surface disposal of low-level waste (LLW), geologic repository and other disposal concepts, and transportation processes for nuclear fuel, LLW, SNF, transuranic, and high-level waste.
Date: March 1, 2008
Creator: Shropshire, D. E.; Williams, K. A.; Boore, W. B.; Smith, J. D.; Dixon, B. W.; Dunzik-Gougar, M. et al.
Partner: UNT Libraries Government Documents Department