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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

Archaeological investigation and technological analysis of the Quartz Mountain Obsidian Quarry, central Oregon

Hatch, John B. 13 May 1998 (has links)
The Quartz Mountain Obsidian Quarry is located in the Southeast corner of the Bend Fort Rock Ranger District in central Oregon, approximately forty-five miles southeast of Bend, Oregon. The research of the Quartz Mountain Obsidian Quarry began with a literature search of other quarry sites in the area and the use of aerial photos to determine the survey area. After the survey area was established a ground survey was conducted. Following the survey several key areas were chosen for surface collections that could answer key questions: What types of core reductions were being used on Quartz Mountain?; and What types of materials were being utilized? (red/black obsidian found in rhyolite veins, red/black obsidian found in fist sized and larger nodule form, or large block black obsidian). In order to answer these questions three collection units were established. The lithic material from the units was collected and analyzed and the information placed into a database, which was then grouped for statistical analysis, and generated into charts and tables. The resulting data was then compared to the information found from an extensive literature search to see how the material that I collected compared to those found at other quarry sites. From this information I was able to determine that two different core reduction methods were being used on Quartz Mountain: blade core and bifacial core. Along with the different core reduction methods a mobility strategy also came into play. In this thesis I will use the data gathered to determine the different core reduction methods and the mobility strategies that are associated with them. / Graduation date: 1998
102

Testing the coastal decline model with flaked stone artifacts from the San Diego region of California

Iversen, David Richard. January 2007 (has links) (PDF)
Thesis (M.A. in anthropology)--Washington State University, May 2007. / Includes bibliographical references (p. 121-133).
103

Development of a bone artifact typology for the Oregon coast

Lindsay, Lee W. 31 May 1990 (has links)
This thesis was to develop a bone artifact typology for the Oregon coast. This typology was used to test the hypothesis that different geographical regions of the Oregon coast would have different artifact assemblages associated with them. These regions, identified by geologist from landform changes, have been defined as: region 1, from the Columbia River to Tillamook Head; region 2, from Tillamook Head to Heceta Head; region 3, from Heceta Head to Cape Arago; region 4, from Cape Arago to the California boarder. Three criteria were used to develop the bone artifact typology; (1) the artifact must be made from bone, antler, or tooth; (2) the use of the artifact as determined from previous experimental archaeology or ethnography; (3) where artifacts were used for a similar purpose, obvious differences in shape and/ or decoration were used. Fifteen sites on the Oregon coast, two to four sites from each region, were used to develop the typology and test the hypothesis. Some patterns were apparent in the distribution of the artifact assemblages from the Oregon coast sites and there appeared to be some tentative corralation with the geographic regions as stated above. Bilaterally barbed harpoons only appear in sites in region 1. Headscratchers only appear in sites in the southern half of the Oregon coast. Evidence suggested that the composite toggling harpoon was developed in the northern northwest coast and was introduced 3000 or more years ago in region 1, and spread slowly down the Oregon coast until it reached region 3 and 4 only 500 years ago. / Graduation date: 1991
104

Inferential Model Predictive Control Of Poly(ethylene Terephthalate) Degradation During Extrusion

Ozbek, Murat Olus 01 September 2003 (has links) (PDF)
Poly(ethylene terephthalate), PET, which is commonly used as a packaging material, is not degradable in nature. As an issue of sustainable development it must be recycled and converted into other products. During this process, extrusion is an important unit operation. In extrusion process, if the operating conditions are not controlled, PET can go under degradation, which results in the loss of some mechanical properties. In order to overcome the degradation of recycled PET (RPET), this study aims the control of the extrusion process. Dynamic models of the system for control purposes are obtained by experimental studies. In the experimental studies, screw speed, feed rate and barrel temperatures are taken as process variables in the ranges of 50 &ndash / 500 rpm, 3.85 &ndash / 8.16 g/min and 270 &ndash / 310 oC respectively. Singular value decomposition (SVD) technique is used for the best pairing between the manipulated &ndash / controlled variables, where screw speed is taken as the manipulated variable and molecular weight of the product is taken as the controlled variable. PID and model predictive controller (MPC) are designed utilizing the dynamic models in the feedback inferential control algorithm. In the simulation studies, the performance of the designed inferential control system, where molecular weight (Mv) of the product is estimated from the measured intrinsic viscosity ([&amp / #951 / ]) of the product, is investigated. The controller utilizing PID and MPC control algorithms are found to be robust and satisfactory in tracking the given set points and eliminating the effects of the disturbances.
105

Direct Georeferencing And Orthorectification Of Airborne Digital Images

Kiraci, Ali Coskun 01 September 2008 (has links) (PDF)
GPS/INS (Global Positioning System / Inertial Navigation System) brings possibility of relaxing the demand for aerial triangulation in stereo model construction and rectification. In this thesis a differential rectification algorithm is programmed with Matlab software for aerial frame camera images. This program is tested using exterior orientation parameters obtained by GPS/INS and images are ortho-rectified. Ground Control Points (GCP) are measured in the orthorectified images and compared with other rectification methods according to RMSE and mean error. Besides, direct georeferencing accuracy is investigated by using GPS/INS data. Therefore, stereo models and ortho-images are constructed by using exterior orientation parameters obtained with both aerial triangulation and GPS/INS integration. GCPs are measured in both stereo models and ortho-images, compared with respect to their RMSE and mean error. In order to determine Digital Elevation Model (DEM) effect in ortho-rectification, different DEM data are used and the results are compared.
106

A Framework For Ranking And Categorizing Medical Documents

Al Zamil, Mohammed Gh. I. 01 June 2010 (has links) (PDF)
In this dissertation, we present a framework to enhance the retrieval, ranking, and categorization of text documents in medical domain. The contributions of this study are the introduction of a similarity model to retrieve and rank medical textdocuments and the introduction of rule-based categorization method based on lexical syntactic patterns features. We formulate the similarity model by combining three features to model the relationship among document and construct a document network. We aim to rank retrieved documents according to their topics / making highly relevant document on the top of the hit-list. We have applied this model on OHSUMED collection (TREC-9) in order to demonstrate the performance effectiveness in terms of topical ranking, recall, and precision metrics. In addition, we introduce ROLEX-SP (Rules Of LEXical Syntactic Patterns) / a method for the automatic induction of rule-based text-classifiers relies on lexical syntactic patterns as a set of features to categorize text-documents. The proposed method is dedicated to solve the problem of multi-class classification and feature imbalance problems in domain specific text documents. Furthermore, our proposed method is able to categorize documents according to a predefined set of characteristics such as: user-specific, domain-specific, and query-based categorization which facilitates browsing documents in search-engines and increase users ability to choose among relevant documents. To demonstrate the applicability of ROLEX-SP, we have performed experiments on OHSUMED (categorization collection). The results indicate that ROLEX-SP outperforms state-of-the-art methods in categorizing short-text medical documents.
107

The lithic technology of a Late Woodland occupation on the Delaware Bay Kimble's Beach site, Cape May County, New Jersey /

Kotcho, James P. January 2009 (has links)
Thesis (M.A.)--Rutgers University, 2009. / "Graduate Program in Anthropology." Includes bibliographical references (p. 435-461).
108

Static types to dynamic variables : re-assessing the methods of prehistoric Huron chipped stone tool documentation and analysis in Ontario

Lerner, Harry, 1969- January 2000 (has links)
An assemblage of prehistoric Huron chipped stone tools has been analyzed in terms of its inherently dynamic properties. It is hypothesized that the series of measurements and ratios that has been developed is more efficient than existing systems for gauging the changing nature of these implements over time. The statistical evaluation of the data revealed strong linear relationships between various pairs of variables, such as projectile point length and tip angle and end scraper bit edge angles and bit height. It was found that comparing these data to other attributes of these tools, such as use-wear traces and reduction techniques, can be very informative about how each category of tools changed through manufacture, use, and maintenance. The results of this analysis were then compared to those of a more traditional study of a contemporaneous collection of Huron stone tools (Poulton, 1985), demonstrating the utility of the techniques developed.
109

The research and development of multi-purpose forms and vessels

Waddle, Robert L. January 2001 (has links)
This creative project consisted of the artist creating various box forms that were to house treasures that were considered special to the artist or the viewer. His childhood memories and his appreciation of streamline design heavily influenced him. Metal is one of the hardest materials to form and shape but the artist was able to create soft edges and curved forms by using his past experience with the material. He experimented with various surface techniques from patinas to sandblasting and polishing to create the appearance he desired in each piece. By combining wood and metal he created successful works that worked well together forming relationships between the two and were visually stimulating. He was able to create boxes within boxes with hidden compartments that could hide special treasures. This project proved to be a success for the artist, not only did he learn more about the building techniques and develop new surface treatments, but he designed and created the pieces he had envisioned at the beginning artistic career. / Department of Art
110

A study of the beamer : a prehistoric hide processing tool

McAlpine, Thomas H. January 2005 (has links)
In archaeology, most studies of artifacts focus on lithics and ceramics, while bone artifacts are often neglected in our intense study of the past. This thesis takes a step in the opposite direction by focusing on a bone tool known as the beamer. This thesis tests the hypothesis that the beamer, used for processing animal hides, is only used during the Late Woodland and Mississippian time periods. If the hypothesis is supported, the beamer would be unique among bone artifacts, acting as a chronological marker similar to projectile points. The thesis also studies how the hypothesized appearance of the beamer at the beginning of the Late Woodland affected the use of lithic scrapers, another tool used for hide processing. Information gathered for this thesis was used to create a large database of Midwestern prehistoric archaeological sites. While the original hypothesis did not hold up, a new hypothesis was created based on the data. / Department of Anthropology

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