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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.
141

Interfaces and control systems for intuitive crane control

Peng, Chen Chih 17 November 2009 (has links)
Cranes occupy a crucial role within the industry. They are used throughout the world in thousands of shipping yards, construction sites, and warehouses. However, payload oscillation inherent to all cranes makes it challenging for human operators to manipulate payloads quickly, accurately, and safely. Manipulation difficulty is also increased by non-intuitive crane control interfaces. Intuitiveness is characterized by ease of learning, simplicity, and predictability. This thesis addresses the issue of intuitive crane control in two parts: the design of the interface, and the design of the controller. Three novel types of crane control interface are presented. These interfaces allow an operator to drive a crane by moving his or her hand freely in space. These control interfaces are dependent on machine vision and radio-frequency-based technology. The design of the controller based on empirical means is also discussed. Various control architectures were explored. It was concluded that a controller with an input shaper within a Proportional Derivative feedback loop produced the desirable crane response. The design of this controller is complemented with a structured design methodology based on root locus analysis and computer numerical methods. The intuitive crane control systems were implemented on a 10-ton industrial bridge crane; simulation and experimental results are presented for validation purposes.
142

Tip-over stability analysis for mobile boom cranes with single- and double-pendulum payloads

Fujioka, Daichi 08 July 2010 (has links)
This thesis investigated a tip-over stability of mobile boom cranes with swinging payloads. Base and crane motion presents a tip-over problem. Attaching complex payloads further complicates the problem. They study began with a single-pendulum payload to analyze a tip-over stability characteristics under different conditions. A simple tip-over prediction model was developed with a goal of limiting a computational cost to a minimum. The stability was characterized by a tip-over stability margin method. The crane's tip-over stability was also represented by the maximum possible payload it can carry throughout the workspace. In a static stability analysis, mobile boom crane was assumed to be stationary, thus with no payload swing. The study provided basic understanding on the relationship between tip-over stability and boom configuration. In a pseudo-dynamic stability analysis, the method incorporated payload swing into the analysis by adding estimated maximum payload swing due to motions. To estimate the angles, differential equations of motions of payload swings were derived. The thesis extended the study to a double-pendulum payload. The maximum swing angles estimated in the single-pendulum case were directly applied to the double-pendulum case. To validate the analytical methods, a full dynamic multi-body simulation model of a mobile boom crane was developed. The predictions from the previous analysis were verified by the simulation results. The prediction model and the analytical methods in the thesis provide a significant tool for practical application of tip-over stability analysis on mobile boom cranes. The experimental results increase the confidence of the study's accuracy.
143

Management of captive whooping cranes (Grus americana) to improve breeding behaviour and success

White, Jennifer L. January 1900 (has links) (PDF)
Thesis (M.E. Des.)--University of Calgary, 2000. / Includes bibliographical references.
144

Developing a Generic Resource Allocation Framework for Construction Simulation

Taghaddos, Hosein Unknown Date
No description available.
145

A Great Debate in Poetic Theory: Brooks, Wheelwright, Crane & Olson

Carrell, Janice 01 May 1971 (has links)
Elder Olson has said that at the Biblical Tower of Babel the people did not begin to talk nonsense but only what seemed like nonsense. This paper concerns an intellectual tower where important debates are held, but unfortunately the language is not a universal one; therefor, because all too often terms have evolved without adequate definition, disagreement occurs where reconciliation appears impossible. The very title of this thesis could be misleading to the reader if he considers debate in its formal sense. What is here intended is the controversy in the efforts of respected scholars to understand and establish the nature of poetry, and for me it is also a personal debate as I follow their assumptions in order to make some judgments in the concluding chapter about their successes and limitations. The informality of the structure of the debate does not diminish the seriousness of its dialectic. To the contrary, the debate is very serious not only to those involved but to any person who concerns himself with the state of the literary arts in the modern world. The debate is among critics representing certain generally defined schools of criticism; however they are not primarily spokesman for a school: they are among the mainstays. Each represents high scholarship, and each is deserving of praise solely as an isolated critic – or a critic without a collective classification. At the same time they each acknowledge themselves to be members of their respective schools of criticism. The debate is not constructed on the basis of two teams, negative and affirmative, with two members for each side. Instead there will be three positions presented by four critics. The essence of the debate is their scholarly struggle to bring to the poetic arts the most responsible and valuable critical approach and their sincere disagreement among themselves as to what the nature of poetry is and how the critic should deal with its subject matter.
146

Assessment of Marine Conditions for Logistics, Operation Envelope and Weather Window for Offshore Projects

Rajesh, Edwin January 2011 (has links)
This thesis describes an assessment of offshore wind farms using a Matlab tool Marine System simulator. This tool helps to analyse the Vessel motion according to different wave heights. From this assessment one can know the correct weather window for offshore operation and other possible techniques to reduce the time delay in operation. This tool is used to simulate a supply vessel motion according to different wave heights. The chosen supply vessel is the default supply vessel in the simulator.
147

Product Development of Terminal Testing Box (TTB)

Visti, Erica January 2015 (has links)
Twenty weeks ago I got the honor to pursue a project for ABB Crane Systems. After success with an innovative direction on their Remote Control Station they wanted a continuation of industrial design in another new product development. The aim was to specify the customer needs and create a concept to a Terminal Test Box (TTB), with hopes to gain momentum and funds for continuation of the project.   The terminals earn their money based on productivity of the quay, meaning that the number of ship-to-shore lifts per minute becomes very important. Clients have requested a solution where they can simulate their cranes to ensure function. At the moment approximately five prototypes have been delivered, for example to Peel Ports in Liverpool and Lazaro Cardenas in Mexico. The current Test box lack a proper casing and user adapted features. Based on interviews with personnel at Crane Systems representing linked/adjacent work with TTB the customer needs was determined to: a solution adapted to commissioning phase,a process panel easy to reach, access to components without exposing them, oversight of components and ability to move TTB. The test box is used either standing on the floor or placed on a table. Placed on the floor the operator must twist and bend to access the box, leading to an unpleasant working posture. Set on the table the box is bulky.   The initial idea development resulted in three potential positions and seven initial concepts. Of these seven three ideas was conceptualized and graded in Pughs matrix. The concept Stand high offered a convenient and ergonomic solution independent of the available interior in commissioning phase. However Stand high had weaknesses where the other two concepts Cross and Transparent showed strengths and therefore the three concepts were combined into one. Knowledge about the included components such as an industrial computer and power supply and their requirements has driven the process.   TTB will be produced in approximately ten units per year. The slim edition made it alluring to look into state of the art manufacturing such as Additive Manufacturing compared to the more traditional use of shielded metal. Possibilities regarding the small series can be used by ABB for continuously trying the product towards the customer and offer a flexible product that can be individually adapted to some extent.   The final concept of TTB is improved compared to the Test box looking at horizontal and vertical spacing between the components, which also enables cable channels. The process panel included has an inclination of 15 degrees to avoid reflections as much as possible and to create an ergonomic working position. It has a see through front door giving access and viewing of the components. A combined CNC and 3D-printing prototype/product from the company HLH in aluminum and Plexiglas would cost approximately 24 750 SEK. Manufacturing in shaped sheet metal at Sweco (without a see through door) would cost approximately 10 000 SEK. This is creating an exciting situation, where the recommendation is to create a prototype to further evaluate the concept into completion.
148

Lateral Buckling Of Overhanging Beams

Ozdemir, Kerem Murat 01 August 2005 (has links) (PDF)
Lateral torsional buckling should be taken into account during the design of overhanging steel beams. One special type of overhanging beams is the crane trolley monorails. Lateral buckling of overhanging monorails under idealized loading and boundary conditions has been studied in the past using classical mathematical procedures. This thesis aims to present a detailed investigation of overhanging monorails using finite element analysis. Effects of different loading and boundary conditions were studied in detail. It was found out that the location of loading and supports on the cross section have significant effects on the buckling capacity. Beams having different warping and torsional properties were analyzed. The effects of cross section distortion on buckling capacity were investigated for beams with single and double overhangs. The reduction in capacity due to cross section distortion has been quantified. Based on the analysis results simple design recommendations were developed for lateral buckling of overhanging monorails and they are presented herein.
149

Of being numerous : representations of crowds and anonymity in late-nineteenth and early-twentieth century urban America /

Esteve, Mary Gabrielle. January 1995 (has links)
Thesis (Ph.D.)--University of Washington, 1995. / Vita. Includes bibliographical references (leaves [276]-292).
150

The Dantean image of Ezra Pound, T.S. Eliot and Hart Crane

Bullaro, John Joseph, January 1962 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1962. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 238-248).

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