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Hydrogenation of Petroleum and Lignite Tar Distillates

Description: Report issued by the U.S. Bureau of Mines regarding the operation of the Coal Hydrogenation Demonstration Plant in Missouri. This report summarizes the operating experience gained and the characteristics of the products created during operation of the plant. The report includes graphs, tables, and illustrations.
Date: April 1950
Creator: Clarke, E. A.; Chaffee, C. C. & Hirst, L. L.
Partner: UNT Libraries Government Documents Department

A fast contour descriptor algorithm for supernova imageclassification

Description: We describe a fast contour descriptor algorithm and its application to a distributed supernova detection system (the Nearby Supernova Factory) that processes 600,000 candidate objects in 80 GB of image data per night. Our shape-detection algorithm reduced the number of false positives generated by the supernova search pipeline by 41% while producing no measurable impact on running time. Fourier descriptors are an established method of numerically describing the shapes of object contours, but transform-based techniques are ordinarily avoided in this type of application due to their computational cost. We devised a fast contour descriptor implementation for supernova candidates that meets the tight processing budget of the application. Using the lowest-order descriptors (F{sub 1} and F{sub -1}) and the total variance in the contour, we obtain one feature representing the eccentricity of the object and another denoting its irregularity. Because the number of Fourier terms to be calculated is fixed and small, the algorithm runs in linear time, rather than the O(n log n) time of an FFT. Constraints on object size allow further optimizations so that the total cost of producing the required contour descriptors is about 4n addition/subtraction operations, where n is the length of the contour.
Date: July 16, 2006
Creator: Aragon, Cecilia R. & Aragon, David Bradburn
Partner: UNT Libraries Government Documents Department

An Inquiry into the Inevitability of Prediction Error in Investment Portfolio Models

Description: Many mathematical programming models of the selection of investment portfolios assume that the best portfolio at any given level of risk is the portfolio having the highest level of return. The expected level of return is defined as a linear combination of the expected returns of the individual investments contained within the portfolio,and risk is defined in terms of variance of return. This study uses Monte Carlo simulation to establish that if the estimates of the future returns on potential investments are unbiased, the steady-state return on the portfolio is overestimated by the procedure used in the standard models. Under reasonable assumptions concerning the parameters of the estimates of the various returns, this bias is quite sizeable, with the steady-state predicted return often overestimating the steady-state actual return by more than ten percentage points. In addition, it is shown that when the variances of the alternative potential investments are not all equal,a limitation on the variance of the portfolio will reduce the magnitude of the bias. In many reasonable cases, constraining the portfolio variance reduces the bias by a magnitude greater than the amount by which it reduces the predicted portfolio return, causing the steady-state actual return to rise. This implies that return cannot automatically be assumed to be a monotonic function of risk.
Date: December 1972
Creator: Valentine, Jerome Lynn
Partner: UNT Libraries

Scientific Workstation Evaluation Project: Multidisciplinary Experience with a Scientific Workstation

Description: This document is a formal report on the scientific workstation evaluation project. The objective of this project has been to evaluate a scientific workstation. When new computing systems appeared that exhibited the capabilities necessary to do scientific computing work at relatively low equipment cost, both the staff of the Argonne scientific divisions and we (the Computing Services staff) wished to know more about the equipment and the vendor claims.
Date: December 1984
Creator: Raffenetti, Richard C.; Carruthers, Clifford M.; Birgersson, Goran; Blomquist, R. N.; Kennedy, James M.; Koelling, Dale D. et al.
Partner: UNT Libraries Government Documents Department

A word processing curriculum model for post-secondary educational institutions

Description: The subject of this study is a curricular model in word processing for post-secondary programs of business education. The study had the following purposes: to survey the present emphasis upon word processing in programs of business education; to survey the current use of word processing in business; to identify the characteristic form of word processing systems; to survey the need for qualified personnel for employment in word processing; to evaluate current educational practices in educating individuals for positions in word processing; and to utilize findings from both business and education to construct a curricular model for post-secondary educational institutions.
Date: December 1978
Creator: Gillard, Sharlett Kay Wolfe
Partner: UNT Libraries

Breaking the Curse of Cardinality on Bitmap Indexes

Description: Bitmap indexes are known to be efficient for ad-hoc range queries that are common in data warehousing and scientific applications. However, they suffer from the curse of cardinality, that is, their efficiency deteriorates as attribute cardinalities increase. A number of strategies have been proposed, but none of them addresses the problem adequately. In this paper, we propose a novel binned bitmap index that greatly reduces the cost to answer queries, and therefore breaks the curse of cardinality. The key idea is to augment the binned index with an Order-preserving Bin-based Clustering (OrBiC) structure. This data structure significantly reduces the I/O operations needed to resolve records that cannot be resolved with the bitmaps. To further improve the proposed index structure, we also present a strategy to create single-valued bins for frequent values. This strategy reduces index sizes and improves query processing speed. Overall, the binned indexes with OrBiC great improves the query processing speed, and are 3 - 25 times faster than the best available indexes for high-cardinality data.
Date: April 4, 2008
Creator: Wu, Kesheng; Wu, Kesheng; Stockinger, Kurt & Shoshani, Arie
Partner: UNT Libraries Government Documents Department

Introduction to STARPAC: the Standards Time Series and Regression Package

Description: From preface: STARPAC documentation is being published as a series of Technical Notes. This Note is the first in the series. It gives an overview of the STARPAC library, defines conventions used in the documentation, provides an example using STARPAC subroutines, and presents general background material. This Note includes information which is essential for using the STARPAC library, and users should be familiar with its contents before attempting to use any STARPAC subroutine.
Date: October 1983
Creator: Donaldson, Janet R. & Tryon, Peter V.
Partner: UNT Libraries Government Documents Department

Research and Development in the Computer and Information Sciences: [Part] 2. Processing, Storage, and Output Requirements in Information Processing Systems: A Selective Literature Review

Description: From Introduction: "This is the second in a series of reports concerned with research and development requirements and areas of continuing concern in the computer and information sciences and technologies."
Date: May 1970
Creator: Stevens, Mary Elizabeth
Partner: UNT Libraries Government Documents Department

Networks and Natural Language Processing

Description: Article discussing networks and natural language processing. The authors present some of the most successful graph-based representations and algorithms used in language processing and try to explain how and why they work.
Date: September 2008
Creator: Radev, Dragomir R. & Mihalcea, Rada, 1974-
Partner: UNT College of Engineering

A Programming Language For Concurrent Processing

Description: This thesis is a proposed solution to the problem of including an effective interrupt mechanism in the set of concurrent- processing primitives of a block-structured programming language or system. The proposed solution is presented in the form of a programming language definition and model. The language is called TRIPLE.
Date: August 1972
Creator: Jackson, Portia M.
Partner: UNT Libraries

Processing Instruction and Teaching Proficiency Through Reading and Storytelling: A Study of Input in the Second Language Classroom

Description: This paper reports a study of VanPatten's processing instruction (PI) and Ray's TPRS. High school students in a beginning Spanish course were divided into three groups (PI, TPRS, and control) and instructed in forms using the Spanish verb gustar. Treatment included sentence-level and discourse-level input, and tests included interpretation and production measures in a pretest, an immediate posttest, and a delayed posttest given two and a half months following treatment. The PI group made the greatest gains in production measures and in a grammaticality judgment test, and the TPRS group made the greatest gains in written fluency. The PI group's statistical gains in production measures held through the delayed posttest.
Date: May 2011
Creator: Foster, Sarah Jenne
Partner: UNT Libraries

Topic Modeling on Historical Newspapers

Description: Paper for the 2011 ACL Workshop on Language Technology for Cultural Heritage, Social Sciences, and Humanities. This paper discusses topic modeling on historical newspaper.
Date: June 2011
Creator: Yang, Tze-I; Torget, Andrew J., 1978- & Mihalcea, Rada, 1974-
Partner: UNT College of Arts and Sciences

Performance evaluation of two emerging media processors: VIRAM and imagine

Description: This work presents two emerging media microprocessors, VIRAM and Imagine, and compares the implementation strategies and performance results of these unique architectures. VIRAM is a complete system on a chip which uses PIM technology to combine vector processing with embedded DRAM. Imagine is a programmable streaming architecture with a specialized memory hierarchy designed for computationally intensive data-parallel codes. First, we present a simple and effective approach for understanding and optimizing vector/stream applications. Performance results are then presented from a number of multimedia benchmarks and a computationally intensive scientific kernel. We explore the complex interact ions between programming paradigms, the architectural support at the ISA lever and the underlying microarchitecture of these two systems. Our long term goal is to evaluate leading media microprocessors as possible building blocks for future high performance systems.
Date: January 1, 2003
Creator: Oliker, Leonid; Duell, Jason; Narayanan, Manikandan & Chatterji, Sourav
Partner: UNT Libraries Government Documents Department

The Design of Microcomputer-Based Sound Synthesis Hardware

Description: Microcomputer-based music synthesis hardware is being developed at North Texas State University (NTSU). The work described in this paper continues this effort to develop hardware designs for inexpensive, but good quality, sound synthesizers. In order to pursue their activities, researchers in computer assisted instruction in music theory, psychoacoustics, and music composition need quality sound sources. The ultimate goal of my research is to develop good quality sound synthesis hardware which can fill these needs economically. This paper explores three topics: 1) how a computer makes music--a short nontechnical description; 2) what has been done previously--a review of the literature; and 3) what factors bear on the quality of microcomputer-based systems, including encoding of musical passages, software development, and hardware design. These topics lead to the discussion of a particular sound synthesizer which the author has designed.
Date: May 1980
Creator: Hamilton, Richard L.
Partner: UNT Libraries