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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.
21

Raw materials and evolution of lithic technology in Upper Pleistocene Korea /

Seong, Chuntaek, January 2001 (has links)
Thesis (Ph. D.)--University of Washington, 2001. / Vita. Includes bibliographical references (leaves 261-283).
22

Some sources of variation in projectile point form

Brown, Jeffrey Lawrence, 1941- January 1969 (has links)
No description available.
23

Development of a model to predict the tracking performance of cultivators and chisel ploughs /

Hobby, Brenton M. Unknown Date (has links)
Thesis (PhD)--Unversity of South Australia, 1997
24

Interactions of the cutting edge of tillage implements with soil /

Fielke, John Milton. January 1994 (has links) (PDF)
Thesis (Ph. D.)--University of Adelaide, 1994. / Includes bibliographical references (leaves 217-225).
25

Archaeological investigations of stone tool heat-treatment technology in southeastern Missouri : an experimental approach /

McCutcheon, Patrick T. January 1997 (has links)
Thesis (Ph. D.)--University of Washington, 1997. / Vita. Includes bibliographical references (leaves [429]-461).
26

Bone tools from the early hominid sites, Gauteng: an experimental approach

Van Ryneveld, Karen January 2003 (has links)
Thesis (M.Sc. (Palaeoarchaeology))--University of the Witwatersrand, Faculty of Science, 2003 / This project was inspired by the identification of 108 bone tools (dated roughly to between 2 and 1 Mya) from sites in the Cradle of Humankind World Heritage Site, Gauteng. An experimental study was lUldertaken in an attempt to answer the basic question of "what caused modification marks on early hominid bone tools?" Five experimental tools were used in each of seven different task oriented experiments. The purpose of this project was to broaden the existing database of experimentally employed bone tools and the associated process-pattern relationships. Analysis was based on an optical comparison of primarily microscopically, but also macroscopically visible usewear patterns observed on the experimental tools. The experimental data were then used to make inferences on a middle range theoretical level regarding the use of the fossil specimens and comment on the currently held opinions.
27

The development of prehistoric grinding technology in the Point of Pines area, east-central Arizona.

Adams, Jenny Lou. January 1994 (has links)
The development of grinding technology is a topic that has not received much attention from archaeologists in the American Southwest. Presented here is a technological approach to ground stone analysis capitalizing on the methods of ethnoarchaeology, experimentation, and use-wear analysis. These methods are applied to an existing collection of ground stone artifacts amassed by the University of Arizona field school's excavation of the Point of Pines sites in east-central Arizona. The heart of the technological approach is the recognition that technological behavior is social behavior and as such is culturally distinct. Both puebloan and nonpuebloan ethnographies provide models for understanding how ground stone tools were used by different cultural groups in daily activities and for making inferences about gender-specific behaviors. Culturally distinct behaviors are sustained through technological traditions, defined as the transmitted knowledge and behaviors with which people learn how to do things. A technological approach is applied to the ground stone assemblages from nine Point of Pines sites that date within eight phases, from A.D. 400 to A.D. 1425-1450. The assemblages are compared and assessed in terms of variation that might reflect developments in grinding technology. Developments may have derived from local innovations or from introduced technological traditions. Assemblage variation is evaluated in light of major events in Point of Pines prehistory, particularly the change from pit house villages to pueblo villages and the immigration of Tusayan Anasazi. Point of Pines grinding technology continued relatively unchanged until late in the occupation. Around the mid-1200s, an Anasazi group immigrated to the Point of Pines area and took up residence in the largest Point of Pines pueblo. Foreign technology was introduced but not immediately adopted by the resident Mogollon. Food grinding equipment of two different designs coexisted for about 100 years, until around A.D. 1400 when there is evidence of a change in the social organization of food grinding. It is this change that signals the blending of Mogollon and Anasazi into Western Pueblo.
28

A study of selected British and European flint assemblages of Late Devensian and Early Flandrian Age

Barton, R. N. E. January 1986 (has links)
This dissertation is concerned with the analysis of selected blade assemblages from Late Devensian and Early Flandrian contexts in Southern Britain (c. 12,500 - 9,000 BP). The British sites studied are divided into three main groupings: Upper Palaeolithic, Long Blade, and Mesolithic, each of which contains material of a typologically and technologically distinct nature. Despite previous important studies in the British Upper Palaeolithic and Mesolithic, no major work until now has been undertaken on the third technology, that of the Long Blade sites, which seems to occupy a chronological position intermediate between the other two. The dissertation incorporates the first comprehensive description of material from Long Blade sites and contrasts it with the sets of artefacts from the other two groups. Comparative data from the Upper Palaeolithic and Mesolithic derive mainly from primary information recovered in two excavations directed by myself at Hengistbury Head between 1980-4. The chapters consider the archaeological material in chronological order beginning in Chapter 1 with the Late Upper Palaeolithic assemblage from Hengistbury Head. Chapters 2 and 3 are devoted to the Long Blade assemblages from Britain and Northwestern Europe, whilst in the fourth chapter the Early Mesolithic material from Hengistbury and related sites in Southern Britain is considered. The fifth and last chapter is given over to discussion and final conclusions. Appended to the last chapter is a gazetteer of 159 specified Long Blade findspots in Southern Britain, the first time this material has ever been gathered together. Explanatory notes and a key are provided at the front of the Gazetteer. In studying the artefacts I have laid particular emphasis on technology as well as typology, and in studying technology I have been particularly influenced by my own work on the experimental manufacture and use of implements. Given that my two excavated sites were very little disturbed, I have also been able to make major use of conjoining artefacts, not only as an aid to understanding the differing techniques of artefact manufacture, but also in interpreting the archaeology of the sites. Some use was also made of experimental taphonomy. These aspects of my work are referred to in the text, notably in Chapters 1 and 4.
29

Development of the Kansas State University mulch tillage planter

Suderman, Donald A January 2011 (has links)
Typescript (photocopy). / Digitized by Kansas Correctional Industries
30

Transfer of tool affordances in computer vision for robotics

Abelha Ferreira, Paulo January 2018 (has links)
Robots working in constrained environments in the industry have achieved great success for a variety of tasks. Future service robots working in unconstrained domains (e.g. home or hospital) will have to cope with unforeseen circumstances, such as not having the usual tool to perform a known task. They will have to assess the affordances of candidate substitute tools and also how best to grasp and orient a tool (tool-pose) for a given task. Everyday tasks in the home often involve using a tool in non-canonical ways, e.g., the handle of a spoon oriented in the right way to retrieve something from a gap; or a bottle of wine used as a rolling pin to roll dough. It is possible to exploit these similarities between different tools and their tool-poses if the robot can learn by trying different tool-poses and also transfer what was learned to assess substitute candidate tools. Learning and dealing with substitute tools comes naturally to humans and is already present in toddlers and in some animals. Research in cognitive science provides insight into a possible mechanism playing an important role in human concept adaptability: projection. Here we provide an application of this cognitive science idea into the real-world domain of computer vision for service robotics. We show both that projection can be made to work in a real-world domain and that our approach can achieve better results than the closest one in the literature. The two main contributions of this dissertation are: 1. A first approach to bringing the idea of projection from cognitive science into a real-world 3D computer vision domain. Instead of a one-pass assessment from sensor data to abstraction and then to score, we have a bottom-up exploration from sensor data to representation and a top-down selection of best alternatives. 2. A semi-automatic framework for assessing tool affordances and tool-pose starting from unsegmented point clouds and including segmentation, simulation, learning and flexible assessment. These contributions enable us to achieve 69% overall accuracy on five different everyday tasks compared to our closest competitor in the literature achieves only 32% on the same four tasks. These results can be obtained when (a) it is possible to create a simulation for the task (b) it is possible to pre-train the system on 5000 different tools. This dissertation demonstrates that it is possible to bring the projection idea into a real-world domain and that combining top-down pressure with bottom-up search and a flexible representation improves accuracy when assessing tool affordances for service robotics.

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