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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

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

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

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

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

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


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

Preventing industrial pollution at its source: the final report of the Michigan source reduction initiative

Description: This report describes a collaborative effort between NRDC, Dow Chemical, and Michigan Environmental Groups. The effort resulted in the identification and implementation of 17 pollution prevention projects that reduced substantial quantities of wastes and emissions and saved Dow considerable money.
Date: September 1, 1999
Partner: UNT Libraries Government Documents Department


Description: The NGDRS has attained 72% of its targeted goal for cores and cuttings transfers, with over 12M linear feet of cores and cuttings now available for public use. Additionally, large-scale transfers of seismic data have been evaluated, but based on the recommendation of the NGDRS steering committee, cores have been given priority because of the vast scale of the seismic data problem relative to the available funding. The rapidly changing industry conditions have required that the primary core and cuttings preservation strategy evolve as well. A Steering Committee meeting held on November 30, 2000 focused on current achievements, how the situation in the petroleum industry affects the NGDRS activities, and the nature of the study by the National Research Council on data preservation. AGI remained actively involved in assisting the National Research Council with background materials and presentations for their panel convened to study the data preservation issue. The GeoTrek metadata catalog system continues to expand and attract new users. Current GeoTrek revision efforts are being retargeted given the identification of new open source technologies with will provide for a flexible, user-friendly GeoTrek, Version 3.
Date: April 1, 2001
Creator: Milling, Marcus
Partner: UNT Libraries Government Documents Department

Impact of the implementation of MPI point-to-point communications on the performance of two general sparse solvers

Description: We examine the mechanics of the send and receive mechanism of MPI and in particular how we can implement message passing in a robust way so that our performance is not significantly affected by changes to the MPI system. This leads us to using the Isend/Irecv protocol which will entail sometimes significant algorithmic changes. We discuss this within the context of two different algorithms for sparse Gaussian elimination that we have parallelized. One is a multifrontal solver called MUMPS, the other is a supernodal solver called SuperLU. Both algorithms are difficult to parallelize on distributed memory machines. Our initial strategies were based on simple MPI point-to-point communication primitives. With such approaches, the parallel performance of both codes are very sensitive to the MPI implementation, the way MPI internal buffers are used in particular. We then modified our codes to use more sophisticated nonblocking versions of MPI communication. This significantly improved the performance robustness (independent of the MPI buffering mechanism) and scalability, but at the cost of increased code complexity.
Date: October 10, 2001
Creator: Amestoy, Patrick R.; Duff, Iain S.; L'Excellent, Jean-Yves & Li, Xiaoye S.
Partner: UNT Libraries Government Documents Department

Expanding the Search for Digital Preservation Solutions: Adopting PREMIS in Cultural Heritage Institutions

Description: Paper accompanying a poster presentation for the 2009 ACM/IEEE-CS Joint Conference on Digital Libraries. This paper provides some preliminary results on factors that affect the adoption of PREMIS (Preservation Metadata Implementation Strategies) in cultural heritage institutions.
Date: 2009
Creator: Alemneh, Daniel Gelaw
Partner: UNT Libraries

Implementation of modal combination rules for response spectrum analysis using GEMINI

Description: One of the widely used methodologies for describing the behavior of a structural system subjected to seismic excitation is response spectrum modal dynamic analysis. Several modal combination rules are proposed in the literature to combine the responses of individual modes in a response spectrum dynamic analysis. In particular, these modal combination rules are used to estimate the representative maximum value of a particular response of interest for design purposes. Furthermore, these combination rules also provide guidelines for combining the representative maximum values of the response obtained for each of the three orthogonal spatial components of an earthquake. This report mainly focuses on the implementation of different modal combination rules into GEMINI [I].
Date: June 1, 1999
Creator: Nukala, P K
Partner: UNT Libraries Government Documents Department

A Case for Including Transactions in OpenMP

Description: Transactional Memory (TM) has received significant attention recently as a mechanism to reduce the complexity of shared memory programming. We explore the potential of TM to improve OpenMP applications. We combine a software TM (STM) system to support transactions with an OpenMP implementation to start thread teams and provide task and loop-level parallelization. We apply this system to two application scenarios that reflect realistic TM use cases. Our results with this system demonstrate that even with the relatively high overheads of STM, transactions can outperform OpenMP critical sections by 10%. Overall, our study demonstrates that extending OpenMP to include transactions would ease programming effort while allowing improved performance.
Date: January 25, 2010
Creator: Wong, M; Bihari, B L; de Supinski, B R; Wu, P; Michael, M; Liu, Y et al.
Partner: UNT Libraries Government Documents Department

Multi Dimensional Phase Only Filter

Description: Today's sensor networks provide a wide variety of application domain for high-speed pattern classification systems. Such high-speed systems can be achieved by the use of optical implementation of specialized POF correlator. In this research we discuss the modeling and simulation of the phase only filter (POF) in the task of pattern classification of multi-dimensional data.
Date: July 13, 2004
Creator: Gudmundsson, K & Awwal, 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