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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.
241

Manipulátor nástrojů pro svislý zásobník nástrojů / Manipulator of Tools used for vertical tool magazine

Fiebiger, Radek January 2010 (has links)
The aim of this thesis is to design different variants, choose an optimal one and the constructional solution of a tool manipulator for vertical lathe from SKG line by TOS HULÍN a.s. This thesis also includes technical and economical report. There is a solution of a basic conception, main dimensions, functional calculations and calculations of rigidity of chosen parts of this manipulator. All computations and methods are in accord with valid standards.
242

Návrh řetězového zásobníku nástrojů / Design of chain tool magazine

Mucha, Roman January 2011 (has links)
The aim of the Master´s thesis is to design a chain tool magazine for a heavy duty machining centre for the non-rotational parts production. The Master’s thesis is ordered by TOS KURIM - OS, a.s. Company. The first part contains the analysis of the solved problems with the overview on the automatic tool changers, and the next part of the thesis deals with the proposal of options. Design of the chosen solution of the chain tool magazine is made in the next step, including sizing of the main parts. The 3D model of the chain tool magazine and drawings are included.
243

A Unified 2D Solver for Modeling Carrier and Defect Dynamics in Electronic and Photovoltaic Devices

January 2019 (has links)
abstract: Semiconductor devices often face reliability issues due to their operational con- ditions causing performance degradation over time. One of the root causes of such degradation is due to point defect dynamics and time dependent changes in their chemical nature. Previously developed Unified Solver was successful in explaining the copper (Cu) metastability issues in cadmium telluride (CdTe) solar cells. The point defect formalism employed there could not be extended to chlorine or arsenic due to numerical instabilities with the dopant chemical reactions. To overcome these shortcomings, an advanced version of the Unified Solver called PVRD-FASP tool was developed. This dissertation presents details about PVRD-FASP tool, the theoretical framework for point defect chemical formalism, challenges faced with numerical al- gorithms, improvements for the user interface, application and/or validation of the tool with carefully chosen simulations, and open source availability of the tool for the scientific community. Treating point defects and charge carriers on an equal footing in the new formalism allows to incorporate chemical reaction rate term as generation-recombination(G-R) term in continuity equation. Due to the stiff differential equations involved, a reaction solver based on forward Euler method with Newton step is proposed in this work. The Jacobian required for Newton step is analytically calculated in an elegant way improving speed, stability and accuracy of the tool. A novel non-linear correction scheme is proposed and implemented to resolve charge conservation issue. The proposed formalism is validated in 0-D with time evolution of free carriers simulation and with doping limits of Cu in CdTe simulation. Excellent agreement of light JV curves calculated with PVRD-FASP and Silvaco Atlas tool for a 1-D CdTe solar cell validates reaction formalism and tool accuracy. A closer match with the Cu SIMS profiles of Cu activated CdTe samples at four different anneal recipes to the simulation results show practical applicability. A 1D simulation of full stack CdTe device with Cu activation at 350C 3min anneal recipe and light JV curve simulation demonstrates the tool capabilities in performing process and device simulations. CdTe device simulation for understanding differences between traps and recombination centers in grain boundaries demonstrate 2D capabilities. / Dissertation/Thesis / Doctoral Dissertation Electrical Engineering 2019
244

A qualitative feasability study to evaluate the use of a screening tool to detect neurocognitive deficits among perinatally HIV-infected children by primary health care workers

Moos, Anbrenthia January 2020 (has links)
Magister Public Health - MPH / Despite the effectiveness and scale-up of antiretroviral treatment (ART), HIV-Associated neurocognitive disorders (HAND) still persist. Currently no gold standard tool exists to detect all forms of HAND, including major and minor cognitive impairments. In light of this, a newly developed screening tool was conceptualised, namely the Quick Paediatric Neurocognitive Screening tool (QPNST). The QPNST has been developed to detect HAND in perinatally HIV-infected children aged 5-10 years.
245

Ein Praxisbericht zur Steigerung der Lehrqualität sowie der studentischen Kollaboration: Ist Webconferencing das richtige Tool?

Rakoczi, Gergely, Herbst, Ilona 26 October 2011 (has links)
Immer mehr E-Learning-Zentren oder Medienstellen von Universitäten bieten Webkonferenztools nicht nur für die universitäre Forschung, sondern auch explizit für die universitäre Lehre an (siehe Abbildung 1). Für den Einsatz dieses Werkzeugs wird mit verschiedenen didaktischen Nutzungsszenarien, räumlich getrennten Kollaborationsmöglichkeiten, intensivierter synchroner Wissensvermittlung sowie der vollständigen Abbildung der Präsenzeinheiten auf Virtual Class rooms argumentiert. Auf Seiten der Lehrenden bedeutet der Einsatz von Webkonferenztools einen erhöhten Zeitaufwand an Lehrvorbereitung, -Abwicklung sowie -Nachbereitung. Diesem Zeitaufwand muss ein deutlicher didaktischer Mehrwert gegenüber stehen, wenn Webconferencing keine „Eintagsfliege“ in der präsenzuniversitären Lehre sein soll. Der didaktische Mehrwert kann in der Steigerung der Lehrqualität sowie der studentischen Kollaboration gesehen werden. Dieses Paper stellt nun unsere Erfahrungen – die aus einem langjährigen Einsatz des Webconferencingtools exzerpiert werden konnten – dar, diskutiert Stolpersteine und zeigt lehrqualitätssteigernde Szenarien auf.
246

SWAT Online: Development of a Web-Based Decision Support System for the Soil and Water Assessment Tool

McDonald, Spencer Dean 01 December 2018 (has links)
As satellite and climate modelling technology continues to improve and as climatological disasters and issues continue to impact the global community, climate data will increase in size and relevance. With this new influx of information, it is becoming more and more important for scientists to simply and concisely communicate their findings to both decision makers in governments and disaster preparedness organizations and also to the general public. The Soil and Water Assessment Tool (SWAT) is a powerful modelling tool that allows scientists to simulate essentially all of the physical processes involved in the water cycle. The data that SWAT produces can be valuable information as people strive to better plan for and understand various hydrologic events. The work presented in this thesis represents an effort to overcome some of the limitations of the previously developed SWAT visualization software by creating a set of modular web applications that can be duplicated, customized, and run by any organization or individual interested in visualizing and sharing data from SWAT. By eliminating the technical knowledge barriers that are inherent in running and using SWAT models, this work has the potential to increase SWAT’s impact on non-technically trained stakeholders and decision makers in areas where water and climate management is important.
247

Visualiseringsverktyg för modulärproduktutveckling : En studie om designen och implentationen av ett verktyg som ska effektivisera ett modulärt arbetssätt

Holm, Mathias January 2014 (has links)
Due to a growing interest in communication in today’s society the demand for equipment that is used in communication networks increases while the competition between companies that produce this equipment grows. To meet the increasing demand and at the same time having a competitive product development many companies use some effective product design, such as the modular product design. When a modular product design is used it’s good to compare different module configurations for a certain product and to simplify these comparisons some tool can be used. This work examines the design and development of a tool that visualize information about different modular plans in a web interface. The focus of the work is on the storage and processing of data to be presented and also the software architecture, namely the back-end of the tool. The front-end consists of a web interface that is developed and described in another thesis. Different techniques to store data are examined and data models are developed. A multitier architecture, more precisely three tiers, is used in the tool where the three tiers are one tier for the data storage, one tier for the processing of data and one for the web interface. A relational database is used as data storage and to process data the programing language Java is used. To communicate between the web interface and the tier that process data a RESTful API is used.
248

Tool condition analysis and monitoring in cold rolling process

El Siblani, Ali January 2011 (has links)
This research is about a costly problem in the automotive industry due to tool fracture during the splines cold rolling of steel shafts. The objective is to study the cause of this failure and propose solutions that can be implemented in the workshop.The writing starts with a brief introduction of the companies involved in shafts production and problem solving. It introduces the cold rolling process and its advantages on splines manufacturing, and it goes through relevant material and process characteristics that help to determine the cause of tool fracture.In order to understand the process failure and production flow, it has been necessary to build up an Ishikawa diagram with possible tool fracture causes. After collecting and analysing the data about the machine tool, cold rolling process and work-piece and rolling tool materials, tests and experiments have been done.It has been considered that there is a rolling tool fatigue that causes tool fracture. Beside tool fracture, two more problems with production flow instability and the right side rolling tool have been detected. Testing the material hardness of the work-piece has shown continuous hardness fluctuations from the supplier. Rolling tool misalignment has been measured by using a vernier caliper measurement device. Rolling tools material hardness analysis shows that tool is very hard and it is possible to use a tougher material which responds better to cyclic loads.Leax has tried to solve the problem by testing another lubrication and tool coatings. A modal analysis test has been performed in order to find the natural frequency of the work-piece which possibly may lead to vibration and over loading one of the rolling tools.The conclusion that has been reached is that main cause of fracture is rolling tool fatigue due to cyclic loads and it is important to use other rolling tool material. The other two detected problems, production flow instability and rigth side rolling tool fracture, should be considered as a part of the problem in order to significantly increase tools life and stabilize production flow rate.
249

Evaluation of an Opioid Risk-Assessment Screening Tool

Guerra, Jacquelyne 01 January 2018 (has links)
According to the Centers for Disease Control and Prevention, prescribers should evaluate risk factors related to opioid use prior to initiation of opioid medication. The practice problem in this DNP project was that providers failed to consistently assess patients with complaints of pain for risk of opioid misuse and/or abuse prior to initiating opioid medication. An opioid risk-assessment screening tool (ORAST) has the potential to identify patients at high risk for opioid misuse and/or abuse. The purpose of this Doctor of Nursing Practice project was to identify and introduce an ORAST and then develop a policy to guide providers in its use in an ambulatory care clinic. Rosswurm and Larrabee's model for evidence-based practice served as the framework that helped guide project development. Evidence in the literature review supported The Opioid Risk Tool (ORT) as the most appropriate tool for the clinic. An 11-member project team voted unanimously for the ORT and to develop a policy to guide the use of the tool in the clinic. The ORT and its policy were evaluated by the team using the AGREE II Instrument. The team agreed that the ORT and its policy should be implemented into their practice setting (64% strongly agreed and 36% moderately agreed). A summative evaluation supported the Doctor of Nursing Practice student leadership of the project. Use of an ORAST has the potential to create positive social change by reducing the number of prescribed opioid by assisting providers in determining a patient's plan of care based on the patient's level of risk for prescription opioid misuse and/or abuse. Patient outcomes may be improved through reduction in opioid misuse and/or abuse.
250

Milling Tool Condition Monitoring Using Acoustic Signals and Machine Learning

Cooper, Clayton Alan January 2019 (has links)
No description available.

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