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An Empirical Investigation of Critical Factors that Influence Data Warehouse Implementation Success in Higher Educational Institutions

Description: Data warehousing (DW) in the last decade has become the technology of choice for building data management infrastructures to provide organizations the decision-making capabilities needed to effectively carry out its activities. Despite its phenomenal growth and importance to organizations the rate of DW implementation success has been less than stellar. Many DW implementation projects fail due to technical or organizational reasons. There has been limited research on organizational factors and their role in DW implementations. It is important to understand the role and impact of both technical but organizational factors in DW implementations and their relative importance to implementation performance. A research model was developed to test the significance of technical and organizational factors in the three phases of implementation with DW implementation performance. The independent variables were technical (data, technology, and expertise) and organizational (management, goals, users, organization). The dependent variable was performance (content, accuracy, format, ease of use, and timeliness). The data collection method was a Web based survey of DW implementers and DW users sampled (26) from a population of 108 identified DW implementations. Regression was used as the multivariate statistical technique to analyze the data. The results show that organization factors are significantly related to performance. Also, that some variables in the post-implementation phase have a significant relationship with performance. Based on the results of the tests the model was revised to reflect the relative impact of technical and organizational factors on DW performance. Results suggest that in some cases organizational factors have a significant relationship with DW implementation performance. The implications and interpretation of these results provide researchers and practitioners' insights and a new perspective in the area of DW implementations.
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Date: May 2003
Creator: Mukherjee, Debasish
Partner: UNT Libraries

Designing PV Incentive Programs to Promote Performance: A Reviewof Current Practice in the U.S.

Description: In the U.S., the increasing financial support for customer-sited photovoltaic (PV) systems provided through publicly-funded incentive programs has heightened concerns about the long-term performance of these systems. Given the barriers that customers face to ensuring that their PV systems perform well, and the responsibility that PV incentive programs bear to ensure that public funds are prudently spent, these programs should, and often do, play a critical role in addressing PV system performance. To provide a point of reference for assessing the current state of the art, and to inform program design efforts going forward, we examine the approaches to encouraging PV system performance used by 32 prominent PV incentive programs in the U.S. We identify eight general strategies or groups of related strategies that these programs have used to address factors that affect performance, and describe key implementation details. Based on this review, we then offer recommendations for how PV incentive programs can be effectively designed to mitigate potential performance issues.
Date: October 6, 2006
Creator: Barbose, Galen; Wiser, Ryan & Bolinger, Mark
Partner: UNT Libraries Government Documents Department


Description: We display the full anomaly structure of supergravity, including new D-term contributions to the conformal anomaly. This expression has the super-Weyl and chiral U(1){sub K} transformation properties that are required for implementation of the Green-Schwarz mechanism for anomaly cancellation. We outline the procedure for full anomaly cancellation. Our results have implications for effective supergravity theories from the weakly coupled heterotic string theory.
Date: June 10, 2009
Creator: Butter, Daniel & Gaillard, Mary K.
Partner: UNT Libraries Government Documents Department

Unsymmetric ordering using a constrained Markowitz scheme

Description: We present a family of ordering algorithms that can be used as a preprocessing step prior to performing sparse LU factorization. The ordering algorithms simultaneously achieve the objectives of selecting numerically good pivots and preserving the sparsity. We describe the algorithmic properties and challenges in their implementation. By mixing the two objectives we show that we can reduce the amount of fill-in in the factors and reduce the number of numerical problems during factorization. On a set of large unsymmetric real problems, we obtained the median reductions of 12% in the factorization time, of 13% in the size of the LU factors, of 20% in the number of operations performed during the factorization phase, and of 11% in the memory needed by the multifrontal solver MA41-UNS. A byproduct of this ordering strategy is an incomplete LU-factored matrix that can be used as a preconditioner in an iterative solver.
Date: January 18, 2005
Creator: Amestoy, Patrick R.; S., Xiaoye & Pralet, Stephane
Partner: UNT Libraries Government Documents Department

The effects of structured approaches to computer implementation in small businesses: a study of the relationships between level of systematic approach and implementation time, implementation cost, user satisfaction and level of integration

Description: The purpose of this research is to determine the effects of systematic approach to computer integration on implementation cost, implementation time, user satisfaction, and level of integration in small business environments. It is believed that decreased costs and implementation time result from the use of systematic approaches to computer integration. Systematic approaches may also result in higher user satisfaction and a higher level of system integration.
Date: May 1991
Creator: Savoie, Michael J.
Partner: UNT Libraries

Numerical Predictions for the Demo Enclosure and Comparison to Experiment

Description: The ''demo enclosure'' is a small box meant to simulate the basic characteristics of an equipment enclosure, but without the complexity of an actual enclosure. Extensive experimental measurements have been made on the enclosure and are summarized in a companion report entitled ''Experimental Measurements of the Demo Enclosure''. In this report, we will summarize the associated numerical modeling of the enclosure's structural vibration and radiated sound field using finite and boundary element techniques. One of the main goals of the report is to establish useful modeling guidelines for finite and boundary element analyses of enclosures. Producing accurate predictions is of primary importance, but ease of implementation is also important. We will try to demonstrate that it is not always beneficial to try to duplicate all the enclosure's structural complexity in the finite and boundary element models because errors inevitably occur and it is frequently difficult to adjust the models without considerable effort. For example, it is relatively simple to produce accurate models for shelves and enclosures separately, but their interconnections are much more difficult to represent. When the models are combined into much larger finite element models, it becomes difficult and time consuming to optimize the modeling of the interconnections. Our research was thus directed towards developing simple methods for adjusting the individual models and combining them together after an initial unite element analysis.
Date: February 5, 2004
Creator: Fahnline, JB; Campbell, RL & Hambric, SA
Partner: UNT Libraries Government Documents Department

Implementation of MPICH on Top of MP{_}Lite

Description: The goal of this thesis is to develop a new Channel Interface device for the MPICH Implementation of the MPI (Message Passing Interface) standard using MP{_}Lite. MP{_}Lite is a lightweight message-passing library that is not a full MPI implementation, but offers high performance MPICH (Message Passing Interface CHameleon) is a full implementation of the MPI standard that has the p4 library as the underlying communication device for TCP/IP networks. By integrating MP{_}Lite as a Channel Interface device in MPICH, a parallel programmer can utilize the full MPI implementation of MPICH as well as the high bandwidth offered by MP{_}Lite. There are several layers in the MPICH library where one can tie a new device. The Channel Interface is the lowest layer that requires very few functions to add a new device. By attaching MP{_}Lite to MPICH at the lowest level, the Channel Interface, almost all of the performance of the MP{_}Lite library can be delivered to the applications using MPICH. MP{_}Lite can be implemented either as a blocking or a non-blocking Channel Interface device. The performance was measured on two separate test clusters, the PC and the Alpha miniclusters, having Gigabit Ethernet connections. The PC cluster has two 1.8 GHz Pentium 4 PCs and the Alpha cluster has two 500 MHz Compaq DS20 workstations. Different network interface cards like Netgear, TrendNet and SysKonnect Gigabit Ethernet cards were used for the measurements. Both the blocking and non-blocking MPICH-MP{_}Lite Channel Interface devices perform close to raw TCP, whereas a performance loss of 25-30% is seen in the MPICH-p4 Channel Interface device for larger messages. The superior performance offered by the MPICH-MP{_}Lite device compared to the MPICH-p4 device can be easily seen on the SysKonnect cards using jumbo frames. The throughput curve also improves considerably by increasing the Eager/Rendezvous threshold.
Date: June 27, 2002
Creator: Selvarajan, Shoba
Partner: UNT Libraries Government Documents Department

A 3D Contact Smoothing Method

Description: Smoothing of contact surfaces can be used to eliminate the chatter typically seen with node on facet contact and give a better representation of the actual contact surface. The latter affect is well demonstrated for problems with interference fits. In this work we present two methods for the smoothing of contact surfaces for 3D finite element contact. In the first method, we employ Gregory patches to smooth the faceted surface in a node on facet implementation. In the second method, we employ a Bezier interpolation of the faceted surface in a mortar method implementation of contact. As is well known, node on facet approaches can exhibit locking due to the failure of the Babuska-Brezzi condition and in some instances fail the patch test. The mortar method implementation is stable and provides optimal convergence in the energy of error. In the this work we demonstrate the superiority of the smoothed versus the non-smoothed node on facet implementations. We also show where the node on facet method fails and some results from the smoothed mortar method implementation.
Date: May 2, 2002
Creator: Puso, M A & Laursen, T A
Partner: UNT Libraries Government Documents Department

The Role of Demand Response in Default Service Pricing

Description: Dynamic retail pricing, especially real-time pricing (RTP), has been widely heralded as a panacea for providing much-needed demand response in electricity markets. However, in designing default service for competitive retail markets, demand response has been an afterthought, and in some cases not given any weight at all. But that may be changing, as states that initiated customer choice in the past 5-7 years reach an important juncture in retail market design. Most states with retail choice established an initial transitional period during which utilities were required to offer a default or standard offer generation service, often at a capped or otherwise administratively-determined rate. Many retail choice states have reached the end of their transitional period, and several have adopted or are actively considering an RTP-type default service for large commercial and industrial (C&I) customers. In most cases, the primary reason for adopting RTP as the default service has been to advance policy objectives related to the development of competitive retail markets. However, if attention is paid in its design and implementation, default RTP service can also provide a solid foundation for developing price responsive demand, creating an important link between wholesale and retail market transactions. This article, which draws from a lengthier report, describes experience to date with RTP as a default service, focusing on its role as an instrument for cultivating price responsive demand.1 As of summer 2005, default service RTP was in place or approved for future implementation in five U.S. states: New Jersey, Maryland, Pennsylvania, New York, and Illinois. For each of these states, we conducted a detailed review of the regulatory proceedings leading to adoption of default RTP and interviewed regulatory staff and utilities in these states, as well as eight competitive retail suppliers active in these markets.
Date: November 9, 2005
Creator: Barbose, Galen; Goldman, Charles & Neenan, Bernie
Partner: UNT Libraries Government Documents Department

Design and Implementation of an Open, Interoperable AutomatedDemand Response Infrastructure

Description: This paper describes the concept for and lessons from the development and field-testing of an open, interoperable communications infrastructure to support automating demand response (DR). Automating DR allows greater levels of participation and improved reliability and repeatability of the demand response and customer facilities. Automated DR systems have been deployed for critical peak pricing and demand bidding and are being designed for real time pricing. The system is designed to generate, manage, and track DR signals between utilities and Independent System Operators (ISOs) to aggregators and end-use customers and their control systems.
Date: October 1, 2007
Creator: Piette, Mary Ann; Kiliccote, Sila & Ghatikar, Girish
Partner: UNT Libraries Government Documents Department

Efficient computation of matched solutions of the KV envelopeequation for periodic focusing lattices

Description: A new iterative method is developed to numerically calculate the periodic, matched beam envelope solution of the coupled Kapchinskij-Vladimirskij (KV) equations describing the transverse evolution of a beam in a periodic, linear focusing lattice of arbitrary complexity. Implementation of the method is straightforward. It is highly convergent and can be applied to all usual parameterizations of the matched envelope solutions. The method is applicable to all classes of linear focusing lattices without skew couplings, and also applies to parameters where the matched beam envelope is strongly unstable. Example applications are presented for periodic solenoidal and quadrupole focusing lattices. Convergence properties are summarized over a wide range of system parameters.
Date: January 3, 2006
Creator: Lund, Steven M.; Chilton, Sven H. & Lee, Edward P.
Partner: UNT Libraries Government Documents Department


Description: The steady increase in the power and complexity of modern computer systems has encouraged the implementation of automatic file migration systems which move files dynamically between mass storage devices and disk in response to user reference patterns. Using information describing thirteen months of text editor data set file references, (analyzed in detail in the first part of this paper), they develop and evaluation algorithms for the selection of files to be moved from disk to mass storage. They find that algorithms based on both the file size and the time since the file was last used work well. The best realizable algorithms tested condition on the empirical distribution of the times between file references. Acceptable results are also obtained by selecting for replacement that file whose size times time to last reference is maximal. Comparisons are made with a number of standard algorithms developed for paging, such as Working Set. Sufficient information (parameter values, fitted equations) is provided that our algorithms may be easily implemented on other systems.
Date: October 1, 1978
Creator: Jay Smith, Alan
Partner: UNT Libraries Government Documents Department

LR: Compact connectivity representation for triangle meshes

Description: We propose LR (Laced Ring) - a simple data structure for representing the connectivity of manifold triangle meshes. LR provides the option to store on average either 1.08 references per triangle or 26.2 bits per triangle. Its construction, from an input mesh that supports constant-time adjacency queries, has linear space and time complexity, and involves ordering most vertices along a nearly-Hamiltonian cycle. LR is best suited for applications that process meshes with fixed connectivity, as any changes to the connectivity require the data structure to be rebuilt. We provide an implementation of the set of standard random-access, constant-time operators for traversing a mesh, and show that LR often saves both space and traversal time over competing representations.
Date: January 28, 2011
Creator: Gurung, T; Luffel, M; Lindstrom, P & Rossignac, J
Partner: UNT Libraries Government Documents Department

Development of diagnostics for high-energy petawatt pulses

Description: Applications accessed by high energy petawatt (HEPW) lasers require complete, single-shot characterization of pulse spatial, temporal, and energy characteristics. We describe techniques that enable single-shot characterization of the temporal shape and pulse contrast of HEPW pulses with >10{sup 8} dynamic range over a ns-temporal window. Approaches to measure pulse durations that span two orders of magnitude will be discussed. Finally, we describe a novel implementation of spectrally dispersed two-beam interferometry for measurement of the phase difference between two HEPW pulses. This technique can be applied to dispersion and B-integral measurements in a HEPW system, as well as to achieve precise timing of nanosecond pulses. Lastly, spectrally dispersed interferometry represents an ideal technique to enable coherent addition of HEPW pulses for production of ultrahigh intensities.
Date: June 15, 2006
Creator: Jovanovic, I; Hernandez, J; Appel, G; Barker, D; Betts, S; Brewer, W et al.
Partner: UNT Libraries Government Documents Department

Southern idaho Wildlife Mitigation Implementation 1999 Annual Report.

Description: This report is for the Southern Idaho Wildlife Mitigation Implementation project. This project, implemented by IDFG and SBT wildlife mitigation staff, is designed to protect, enhance and maintain wildlife habitats to mitigate construction losses for Palisades, Anderson Ranch, Black Canyon and Minidoka hydroelectric projects. Additional project information is available in the quarterly reports.
Date: April 1, 2000
Creator: Bottum, Edward & Mikkelsen, Anders
Partner: UNT Libraries Government Documents Department

Southern Idaho Wildlife Mitigation Implementation 2000 Annual Report.

Description: This report covers calendar year 2001 activities for the Southern Idaho Wildlife Mitigation Implementation project. This project, implemented by Idaho Department of Fish and Game and Shoshone Bannock Tribes, is designed to protect, enhance and maintain wildlife habitats to mitigate for construction losses associated with Anderson Ranch, Black Canyon, Deadwood, Minidoka and Palisades hydroelectric projects. Additional project information is available in the quarterly reports.
Date: January 1, 2002
Creator: Bottum, Edward & Mikkelsen, Anders
Partner: UNT Libraries Government Documents Department

Southern Idaho Wildlife Mitigation Implementation 2000 Annual Report.

Description: This report covers calendar year 2000 activities for the Southern Idaho Wildlife Mitigation Implementation project. This project, implemented by Idaho Department of Fish and Game and Shoshone Bannock Tribes wildlife mitigation staff, is designed to protect, enhance and maintain wildlife habitats to mitigate construction losses for Palisades, Anderson Ranch, Black Canyon and Minidoka hydroelectric projects. Additional project information is available in the quarterly reports.
Date: March 1, 2001
Creator: Bottum, Edward & Mikkelsen, Anders
Partner: UNT Libraries Government Documents Department

Reconciling data using Markov Chain Monte Carlo: An application to the Yellow Sea - Korean Peninsula region

Description: In an effort to build seismic models that are most consistent with multiple data sets, we have applied a new probabilistic inverse technique. This method uses a Markov Chain Monte Carlo (MCMC) algorithm to sample models from a prior distribution and test them against multiple data types to generate a posterior distribution. While computationally expensive, this approach has several advantages over a single deterministic model, notably the reconciliation of different data types that constrain the model, the proper handling of uncertainties, and the ability to include prior information. We also benefit from the advantage of forward modeling rather than inverting the data. Here, we use this method to determine the crust and upper mantle structure of the Yellow Sea and Korean Peninsula (YSKP) region. We discuss the data sets, parameterization and starting model, outline the technique and its implementation, observe the behavior of the inversion, and demonstrate some of the advantages of this approach.
Date: August 30, 2004
Creator: Pasyanos, M E; Franz, G A & Ramirez, A L
Partner: UNT Libraries Government Documents Department

Sensitivity study of reliable, high-throughput resolution metricsfor photoresists

Description: The resolution of chemically amplified resists is becoming an increasing concern, especially for lithography in the extreme ultraviolet (EUV) regime. Large-scale screening and performance-based down-selection is currently underway to identify resist platforms that can support shrinking feature sizes. Resist screening efforts, however, are hampered by the absence of reliable resolution metrics that can objectively quantify resist resolution in a high-throughput fashion. Here we examine two high-throughput metrics for resist resolution determination. After summarizing their details and justifying their utility, we characterize the sensitivity of both metrics to two of the main experimental uncertainties associated with lithographic exposure tools, namely: limited focus control and limited knowledge of optical aberrations. For an implementation at EUV wavelengths, we report aberration and focus limited error bars in extracted resolution of {approx} 1.25 nm RMS for both metrics making them attractive candidates for future screening and down-selection efforts.
Date: July 30, 2007
Creator: Anderson, Christopher N. & Naulleau, Patrick P.
Partner: UNT Libraries Government Documents Department

In-situ FPGA debug driven by on-board microcontroller

Description: Often we are faced with the situation that the behavior of a circuit changes in an unpredictable way when chassis cover is attached or the system is not easily accessible. For instance, in a deployed environment, such as space, hardware can malfunction in unpredictable ways. What can a designer do to ascertain the cause of the problem? Register interrogations only go so far, and sometimes the problem being debugged is register transactions themselves, or the problem lies in FPGA programming. This work provides a solution to this; namely, the ability to drive a JTAG chain via an on-board microcontroller and use a simple clone of the Xilinx Chipscope core without a Xilinx JTAG cable or any external interfaces required. We have demonstrated the functionality of the prototype system using a Xilinx Spartan 3E FPGA and a Microchip PIC18j2550 microcontroller. This paper will discuss the implementation details as well as present case studies describing how the tools have aided satellite hardware development.
Date: January 1, 2009
Creator: Baker, Zachary Kent
Partner: UNT Libraries Government Documents Department

Update on Electron-Cloud Simulations Using the Package WARP-POSINST

Description: At PAC05[1] and PAC07[2], we presented the package WARP-POSINST for the modeling of the effect of electron clouds on high-energy beams. We present here the latest developments in the package. Three new modes of operations were implemented: (1) a build-up mode where, similarly to POSINST (LBNL) or ECLOUD (CERN), the build-up of electron clouds driven by a legislated bunch train is modeled in one region of an accelerator; (2) a quasistatic mode where, similarly to HEADTAIL (CERN) or QuickPIC (USC/UCLA), the frozen beam approximation is used to split the modeling of the beam and the electrons into two components evolving on their respective time scales; and (3) a Lorentz boosted mode where the simulation is performed in a moving frame where the space and time scales related to the beam and electron dynamics fall in the same range. The implementation of modes (1) and (2) was primary motivated by the need for benchmarking with other codes, while the implementation of mode (3) fulfills the drive toward fully self-consistent simulations of e-cloud effects on the beam including the build-up phase.
Date: April 1, 2009
Creator: Vay, J.-L.; Celata, Christine M.; Furman, Miguel; Venturini, Marco; Sonnad, Kiran G.; Penn, G. et al.
Partner: UNT Libraries Government Documents Department

Using SPARK as a Solver for Modelica

Description: Modelica is an object-oriented acausal modeling language that is well positioned to become a de-facto standard for expressing models of complex physical systems. To simulate a model expressed in Modelica, it needs to be translated into executable code. For generating run-time efficient code, such a translation needs to employ algebraic formula manipulations. As the SPARK solver has been shown to be competitive for generating such code but currently cannot be used with the Modelica language, we report in this paper how SPARK's symbolic and numerical algorithms can be implemented in OpenModelica, an open-source implementation of a Modelica modeling and simulation environment. We also report benchmark results that show that for our air flow network simulation benchmark, the SPARK solver is competitive with Dymola, which is believed to provide the best solver for Modelica.
Date: June 30, 2008
Creator: Wetter, Michael; Wetter, Michael; Haves, Philip; Moshier, Michael A. & Sowell, Edward F.
Partner: UNT Libraries Government Documents Department

Summary of Workshop: Barriers to Energy Efficient Residential Ventilation

Description: The objectives for this workshop were to bring together those with different viewpoints on the implementation of energy efficient ventilation in homes to share their perspectives. The primary benefit of the workshop is to allow the participants to get a broader understanding of the issues involved and thereby make themselves more able to achieve their own goals in this area. In order to achieve this objective each participant was asked to address four objectives from their point of view: (1) Drivers for energy efficient residential ventilation: Why is this an important issue? Who cares about it? Where is the demand: occupants, utilities, regulation, programs, etc? What does sustainability mean in this context? (2) Markets & Technologies: What products, services and systems are out there? What kinds of things are in the pipeline? What is being installed now? Are there regional or other trends? What are the technology interactions with other equipment and the envelope? (3) Barriers to Implementation: What is stopping decision makers from implementing energy-efficient residential ventilation systems? What kind of barriers are there: technological, cost, informational, structural, etc. What is the critical path? (4) Solutions: What can be done to overcome the barriers and how can/should we do it? What is the role of public vs. private institutions? Where can investments be made to save energy while improving the indoor environment? Ten participants prepared presentations for the workshop. Those presentations are included in sections at the end of this workshop report. These presentations provided the principal context for the discussions that happened during the workshop. Critical path issues were raised and potential solutions discussed during the workshop. As a secondary objective they have listed key issues and some potential consensus items which resulted from the discussions.
Date: January 10, 2008
Creator: Sherman, Max & Sherman, Max
Partner: UNT Libraries Government Documents Department