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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.
351

The Economics of Anaerobic Digester Technology for Ontario Farmers

Anderson, Robert 14 May 2012 (has links)
Anaerobic digester (AD) technology is a form of renewable energy that’s economic feasibility assessment is required site by site. This thesis presents a freely available workbook to determine the financial feasibility of a farm-based AD and to demonstrate its use for the Ontario livestock sector. To assess the profitability of ADs for farmers in Ontario with uncertainty included the theory of real options is used. Investment in an AD is financially feasible only for the largest dairy farms in Ontario under current electricity prices, which are approximately six times greater than the wholesale price. Shifting to a duel fuel continuous system would improve returns, as would the availability of additional substrate material in the form of solid grease waste. The real options approach shows that even higher net returns are necessary, than indicated by more traditional approaches, in order for AD investments to be feasible for Ontario livestock farmers.
352

Mokymosi priemonė braižybos pagrindams įsisavinti / Learning tool to master the fundamentals of drawing

Gedaminskytė, Edita 02 August 2011 (has links)
Inžinerija – plačiausia sritis, kurioje naudojamos braižybos dalyko žinios. Todėl didžiausia dalis užduočių, plakatų ir vadovėlių yra pritaikyta inžinerinę grafiką studijuojantiems studentams. Kuriant naujas specialybes, ugdant kvalifikuotus specialistus atsiranda poreikis suteikti braižybos dalyko žinių nesigilinant į konkrečią sritį. Tam reikia tinkamų grafinių užduočių, susijusių su pasirinktomis studijomis ir specializacija. Ypač reikia TDV specialybės studentams, besirenkantiems skirtingas specializacijas (oda, floristika, aprangos dizainas). Apklausos rezultatai leidžia daryti išvadą, TDV specialybės studentams braižybos pagrindams įsisavinti reikalinga mokymosi priemonė, kurioje būtų pateikiama esminė informacija ir praktinės užduotys žinioms įsisavinti ir braižymo įgūdžiams ugdyti. Mokymosi priemonę sudaro 16 temų, kurios yra svarbios braižybos pagrindams įsisavinti. Šios temos yra integruojamos į kitus mokomuosius dalykus susijusius su grafiniu vaizdavimu. / Engineering – widest field of use of the knowledge of the subject drawing. Thus, much of the task, posters and books are adapted for students studying engineering graphics. The development of new specialties, education of specialists there is a need for drawing the subject of knowledge without going into a specific area. This requires a proper graphic tasks associated with the selected studies and specialization. This is particularly necessary for the students of TDV, choosing different specializations (leather, flowers, clothing design). The survey results suggest that some of the fundamentals of drawing for students to absorb the necessary learning tool, which will provide essential information and practical sessions to absorb knowledge and drawing skills. Learning tool consists of 16 topics which are important to absorb the fundamentals of drawing. These topics are integrated into other subjects that are related with the graphical representation.
353

Žingsninio kosminio strateginio žaidimo kūrimas. Dinaminės grafinės vartotojo sąsajos (GUI) kūrimo problemos ir sprendimai / Development of Turn-Based Space Strategy Game: Development of Dynamic Graphic User Interface (GUI) Problems and Solutions

Levaginas, Saulius 04 August 2011 (has links)
Šis darbas skirtas suprojektuoti ir realizuoti „No Limits“ bibliotekos (biblioteka) klases, atsakančias už sąveiką su „No Limits“ duomenų bazę, ir dinaminės grafinės vartotojo sąsajos generavimo klases, realizuotas bibliotekos galimybėmis. Remiantis projektu, buvo realizuotos klasės sąveikaujančios su duomenų bazę. / The prupose of this work is to create classes of „No Limits“ library, that organizes the way to „No Limits“ database, and create classes that dynamicaly generates graphic user interface from model described in database. Classes for database were created.
354

Design, Analysis, and Prototyping of A 3×PPRS Parallel Kinematic Mechanism for meso-Milling

Zhao, Guan Lei 11 December 2013 (has links)
Parallel Kinematic Mechanisms (PKMs) are well suited for high-accuracy applications such as meso-milling. However, drawbacks such as limited platform tilting angle and high configuration dependency of stiffness often limit their usage. In this Thesis, a new six degree-of-freedom (dof) PKM architecture based on a 3×PPRS topology is proposed, in order to address these problems. The new PKM is presented, and its inverse kinematics and Jocobian matrix are derived. The kinematic relations are incorporated into MATLAB to calculate the workspace of the PKM. The stiffness of the new PKM is obtained using Finite Element Analysis (FEA), and configuration dependency of stiffness is investigated. The proposed new mechanism is compared with three similar existing 6-dof PKMs, and it is shown that the new PKM exhibits higher stiffness. Lastly, three meso-Milling Machine Tool prototypes were designed and built. In particular, Prototype III is based on the new mechanism.
355

A Study of the Performance of Tool-Mounted Displays for Surgical Guidance

Kassil, Kevin D. 25 September 2007 (has links)
In computer-assisted surgery, a computer display provides 3D guidance of tools during surgery. However, current guidance displays have a number of drawbacks. This thesis considers the advantages of a prototype guidance system for drilling tasks. We attached a small LCD screen and video camera to a surgical drill. The screen's point of view was controlled by moving the drill. A user study showed that the tool-mounted LCD screen can provide significantly better positional and angular accuracy than the conventional display. The study also showed that a video camera might not be useful for guidance. / Thesis (Master, Computing) -- Queen's University, 2007-09-18 00:31:10.965
356

An ergonomic evaluation of Speed Fastening work rates

Gooyers, CHAD 02 September 2009 (has links)
Present day manufacturing assembly relies extensively on a variety of fasteners for the assembly of sub-systems, components and trim. Speed Fastening (SF) is one commonly used non-structural assembly fastening method. The primary limitation of SF is the lack of continuously fed rivets. One path to productivity improvement for SF is the development of a continuously feed tool that would eliminate the non-value added time currently scheduled for reloading in the work cycle. In preparation for the design of a new tool, a proactive ergonomic investigation was carried out to examine differences in muscular effort, upper-body posture, as well as subjective ratings of perceived exertion and discomfort across three different work rates for a simulated SF task conducted in a laboratory setting. The purpose of this investigation was to characterize the ergonomic consequences that an increase in work rate would have on SF operators. Twelve healthy female subjects participated in simulated SF work over four test-sessions. The first test session familiarized subjects with the SF tasks as well as the data collection protocol. Subsequent test days, which were scheduled 24 hours apart, were block randomized to one of three work rates (7, 14 and 21 fasteners/min.) with subjects required to complete 120 minutes of a simulated SF task at both waist and shoulder height using a 50% work to rest duty cycle. The results of this study show significant increases in the amount of muscular activity required to complete the simulated SF, particularly for the 21 fasteners per minute work rate, with increases in peak sEMG amplitudes ranging from 3-12% MVIC. Specifically these increases were most marked in the forearm extensor muscles. In addition, significantly deviated postures were found in upper-limb joint ROM data, particularly when SF work was completed at shoulder height. Overall, based on the increased exposure to risk factors known to be precursors for workplace injury (i.e. repetition and awkward posture), it is inferred that an increase in work rate will put SF operators at an elevated risk of musculoskeletal injury. It is expected that this risk would be even more pronounced for work completed at shoulder height. / Thesis (Master, Kinesiology & Health Studies) -- Queen's University, 2009-09-02 00:01:36.701
357

A VISUALIZATION TOOL FOR THE ANALYSIS OF THE EFFECTS OF CHANGING ENERGY POLICIES ON ENERGY SECURITY IN AN ENERGY SYSTEM

Chatharaju, Vinay Kumar 31 October 2013 (has links)
All jurisdictions have an energy system consisting of processes responsible for the conversion and transportation of supplies of energy from various sources to meet the end-use energy demands. Energy systems are dynamic as they respond to uncertainties such as higher energy costs, new energy technologies, public concern over the environmental impacts of energy production, evolving consumption patterns, and the aging of existing infrastructure; these changes can affect the energy suppliers, the end users, and those responsible for operating the energy system. To reduce possible adverse effects and improve the energy security of the system, energy policies are often designed by those responsible for the processes. However, changes to the energy policies can also impact the system’s energy security. Therefore, it is critical to study the possible effects of changing energy policies before they are deployed. To address this problem, a visualization tool has been developed to represent a jurisdiction’s energy system. The tool allows the effects of changing energy policies on energy security to be analysed. A case study using real-time wind data from the City of Summerside has been implemented to demonstrate the capabilities of the tool. This presentation will elaborate on the methods and implementation of the visualization tool and explain the results obtained from the analysis of the Summerside project.
358

Design, Analysis, and Prototyping of A 3×PPRS Parallel Kinematic Mechanism for meso-Milling

Zhao, Guan Lei 11 December 2013 (has links)
Parallel Kinematic Mechanisms (PKMs) are well suited for high-accuracy applications such as meso-milling. However, drawbacks such as limited platform tilting angle and high configuration dependency of stiffness often limit their usage. In this Thesis, a new six degree-of-freedom (dof) PKM architecture based on a 3×PPRS topology is proposed, in order to address these problems. The new PKM is presented, and its inverse kinematics and Jocobian matrix are derived. The kinematic relations are incorporated into MATLAB to calculate the workspace of the PKM. The stiffness of the new PKM is obtained using Finite Element Analysis (FEA), and configuration dependency of stiffness is investigated. The proposed new mechanism is compared with three similar existing 6-dof PKMs, and it is shown that the new PKM exhibits higher stiffness. Lastly, three meso-Milling Machine Tool prototypes were designed and built. In particular, Prototype III is based on the new mechanism.
359

The Making of a Conceptual Design for a Balancing Tool

Eriksson, Jonas January 2014 (has links)
Balancing is usually done in the later phases of creating a game to make sure everything comes together to an enjoyable experience. Most of the time balancing is done with a series of playthroughs by the designers or by outsourced play testers and the imbalances found are corrected followed by more playthroughs. This method occupies a lot of time and might therefore not find everything. In this study I use information gathered from interviews with experienced designers and designer texts along with features from methods frequently used for aiding the designers to make a conceptual design of a tool that is aimed towards simplifying the process of balancing and reducing the amount of work hours having to be spent on this phase.
360

Development and evaluation of a New Zealand Digit Triplet Test for auditory screening.

King, Sharon Mary January 2011 (has links)
The aim of this study was to develop a Digit Triplet Test (DTT) using NZ English. The DTT is a hearing screening tool that uses spoken numbers presented in background noise to estimate speech recognition thresholds (SRTn). The NZ DTT will be made available via telephone or the internet, and will provide each person who completes the screening test with information about whether they should seek a professional hearing assessment. Normal-hearing participants (22 listeners) with hearing thresholds ≤20 dB HL were tested to establish the intelligibility of the individual digits at various signal-to-noise ratios (-20; -17.5; -15.0; -12.5; -10.0; -7.5; and -5.0 dB). The mid-points of the resulting psychometric functions were then used to adjust the level of each digit to achieve the same intelligibility. A SRT of -10.40 ± 1.75 dB SNR for the broadband presentation was established for the separate ear triplet test with the average slope of 17.3%/dB ± 3.9 %/dB for the ten test lists generated. The binaural ear DTT results were compared to best ear threshold PTA and found to have a highly significant correlation (r = 0.816, p<0.001) and a significant correlation to the QuickSIN sentence-in-noise test (r = 0.668, p<0.001). The binaural triplet test was found to have a sensitivity of 100% and specificity of 85%. The separate ear DTT results were compared to the best ear threshold pure tone audiometry and found to have a highly significant correlation (r = 0.809, p<0.001). The separate ear triplet test was found to have a sensitivity of 88% and specificity of 81% (1 – specificity = 0.187). The internet version of the DTT hearing screening test will provide New Zealanders with an easily accessible and objective test that will raise awareness about hearing and hopefully reduce the length of time people take before seeking advice about their hearing.

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