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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.
531

Stormwater Infiltration and Groundwater Integrity: An Analysis of BMP Siting Tools and Groundwater Vulnerability

Gallagher, Kristopher Craig 22 March 2017 (has links)
Nonpoint source pollution captured by urban stormwater runoff is the greatest challenge for surface water quality improvements. Computer-based design tools have been developed to help mediate this issue by guiding end users through the implementation of decentralized stormwater management. The majority of these tools focus on treatment via biofiltration, yet concern regarding this treatment regime is rising. Case studies from research past clearly indicate the susceptibility of groundwater to contamination from extensive anthropogenic activity at the surface. Contaminants, such as nitrates and pathogens, are not completely removed before runoff enters the underground watercourse. Additionally, national and state legislation, which explicitly lists where neglect for groundwater quality is permissible—exacerbate concerns. This research analyzes the efficiency the BMP Siting Tool developed by the US Environmental Protection Agency and the Grey-to-Green Decision Support Tool developed by the University of South Florida. The tools were used to obtain cartographic data illustrating suitable sites for bioswales and infiltration basins throughout northern portion of Hillsborough County, Florida. This data was then integrated with the Karst Aquifer Vulnerability Index (KAVI) groundwater vulnerability model. The area of bioswales and infiltration basins that intersected areas of the KAVI model listed as ‘highly vulnerable’ or ‘moderate-to-highly vulnerable’ was calculated. This permitted an assessment of which BMP facility had the greatest sitings atop vulnerable areas, respective of the tool. The BMP Siting Tool sited 2.80% of all bioswales and 27.89% of all infiltration basins above vulnerable areas. Likewise, the Grey-to-Green Decision Support Tool sited 21.66% of all bioswales and 9.62% of all infiltration basins above vulnerable areas. These results prompted the development of a supplemental groundwater vulnerability framework to be incorporated into both tools’ analytical process.
532

Överflyttning mellan intensivvårdsavdelningar på grund av resursbrist 2009 och 2010 : En jämförande pilotstudie av eventuella skador / Transfers between intensive care units due to lack of resources 2009 and 2010 : A comparative pilot study of possible adverse events

Berggren, Karin, Schmidt-Gustafsson, Rebecka January 2012 (has links)
Bakgrund: Svenska intensivvårdsregistret (SIR) sammanställer varje år fastställda kvalitetsmått där en av dem är ”Överflyttning till annan intensivvårdsavdelning på grund av egen resursbrist.” Flera studier har visat att de patienter som flyttas mellan intensivvårdsavdelningar har en högre mortalitet och längre vårdtid än de som inte flyttas. Enligt patientsäkerhetslagen ska vårdgivaren förebygga och utreda vårdskador. Ett sätt att mäta vårdrelaterade skador är Global Trigger Tool (GTT). Syfte: Att undersöka frekvensen av skador hos de patienter som överflyttats till annan intensivvårdsavdelning på grund av resursbrist jämfört med en matchad kontrollgrupp. Metod: En retrospektiv, deskriptiv och jämförande pilotstudie. Journaler från patienter som flyttats till annan intensivvårdsavdelning på grund av resursbristscannades efter skador med hjälp av GTT och jämfördes sedan med en kontrollgrupp som inte flyttats mellan intensivvårdsavdelningar. Resultat: I undersökningsgruppen (n=20) återfanns 67 skador med ett genomsnitt på 3,4 skador per patient. I kontrollgruppen (n=40) hittades 80 skador med ett genomsnitt på 2,0 skador per patient. Det fanns en stark tendens (p=0,05) till att undersökningsgruppen hade fler antal skador jämfört med kontrollgruppen. Av de patienter som hade sammanlagt sju skador återfanns 15 % i undersökningsgruppen jämfört med 2,5 % i kontrollgruppen. Slutsats: Tendenser ses till att patienter som flyttas på grund av resursbrist har en högre frekvens av skador jämfört med de som inte flyttas. Klinisk betydelse: Om inte överflyttningar på grund av resursbrist kan undvikas, bör i alla fall fler hänsyn tas när beslut om överflyttning sker, såsom exempelvis mått på sjuklighetoch etiska överväganden. / Background: The Swedish Intensive Care Register (SIR) on a yearly basis puts together appointed quality measurements; one of them is entitled ”Transfer to Another Intensive Care Unit Due to Own Lack of Resources.” Several studies have shown that patients that are being transferred between intensive care units have higher mortality rates and longer stay at hospital, compared to those who do not transfer. According to the Swedish Law for Patient Safety the provider of care shall prevent and investigate adverse events. One way of measuring healthcare related adverse events is the Global Trigger Tool method (GTT). Objectives: To investigate the frequency of adverse events in patients who transfer to another intensive care unit due to lack of resources compared to a matched control group. Methods: A retrospective, descriptive and comparative pilot study was conducted. Medical records from patients who were moved to another intensive care unit due to lack of recourses were scanned for adverse events with GTT and then compared with a control group who had not been transferred between intensive care units. Results: In the experimental group (n=20), 67 adverse events were detected with an average of 3, 4 adverse events per patient. In the control group (n=40), 80 adverse events were detected with an average of 2, 0 adverse events per patient. There was a strong possibility (p=0, 05) that the experi-mental group had a higher incidence of adverse events compared to the control group. As much as 15 percent of the patients in the experimental group had been subjected to, in all, seven adverse events, compared to 2, 5 percent in the control group Conclusion: There is a possibility that patients who transfer due to lack of resources have a higher frequency of adverse events than those who do not transfer. Clinical relevance: If transfers due to lack of resources cannot be eliminated when decision about transfers are being made, more consideration should be given to such things as morbidity and ethics.
533

Vícevřetenový vřeteník a zásobník nástrojů pro obráběcí centrum / Multi-spindle headstock and tool magazine for machining center

Jež, Jan January 2021 (has links)
The master‘s thesis deals with the design of the spindle and tool magazine for multispindle machining centre.
534

Metoda pro simulaci energetické náročnosti výrobních strojů v etapě vývoje / Method for Energy Efficience Simulation of Machine Tools in Design Stage

Tůma, Jiří January 2017 (has links)
Ph.D. thesis is focused on the design of the method for simulation of energy demands of machine tool in operation at the stage of its development. Proposed method is developer on the basis of literature search in science and in industry. The method itself is composed of five related steps, that must be realised in the proper order in order to create a relevant energy profile of a machine tool. The output from the method are simulated data providing a course of comsumed energy and required power which are time dependent. Output data are obtained on the basis of the drive system simulation of machine tool through G-code, that is interpreted for simulation by the compiler into the matrix. It contains data necessary for controlling of machine tool, such as the required end points of the tool and required feed rates, to which is assigned a time value. G-code is partially time parametrized. It is then followed by full time parametrization through a of mathematical model of drive mechanisms and due the synergy of software for drive mechanisms control (Matlab Simulink) and software for physical simulation (MSC Adams) is processed into output data. As an input parameter figures also coefficient used as multiplier of the normal force of driving mechanisms, which is a function of feed rate. This loss function is obtained experimantally. In the context of Ph.D. thesis were conducted two experiments, used to verify the developed method. For each experiment is proceeded according to estabilished method and it is included a comparsion of simulation and measured data for various operating modes. The proposed method, described in the Ph.D. thesis, allows designers to summarize the energy demand of the proposed machine before its production. When correctly interpreted, the results of the method can serve as a basis for improving the energy profile and thereby increasing the energy efficiency of the machine tool.
535

Návrh postupu analýzy rizik v projektech technologické přípravy slévárenské výroby / Proposal of a Risk Analysis Procedure in Technological Preparation for Foundry

Krčálová, Žaneta January 2018 (has links)
The author of this diploma thesis deals with the Proposal of a Risk Analysis Procedure in Technological Preparation for Foundry. Risk management is not currently applied in much detail at this present time. Analysis of the present risk management process in serial and prototype model tools will lead to the identification of risks within this discussion. It is then proposed for corrective actions for improvement of managing the current status to be presented and discussed. Target of this thesis is therefore the proposal of an updated risk analysis procedure in technological preparation for foundry.
536

Studie ekonomiky technologie obrábění / The Study of Economics of Tooling Technology

Ondrášek, Dušan January 2008 (has links)
The aim of this diploma thesis addresses issues related to obtaining methodology for the production manager´s decision-making process in the field of technology selection, suitable tooling and cutting tools selection for a specific order or particular production plan. Evaluation of the manufacturing process while taking into consideration complexion of process controlling and contexture to the economy of this process. Analysis and evaluation of technological and economical aspects of a manufacturing process of the CNC chip machining in a real environment is targeted on the field of tooling, its selection, purchase, economy and consumption. The process controlling of technology is based on this analysis as well as the formulation of measuring by economic indicators such as economy, productivity, profitability etc. The analysis of important factors and parameters of this process demonstrated an influence on economy of the company. Several model cases have been created from the company records and from the provided research, the output of which became a basic methodology. The output of the analysis indicates possible directions of a management decision making. Thanks to a complex technical-economic view this thesis can serve as a methodological instrument for decision makers in the field of technology and cutting tool selections as well as an economy of production process improvement.
537

Integrace měření do CNC obrábění / Integration of measurement in CNC machining

Vlček, Michal January 2010 (has links)
This master thesis deals with integration of measuring into process of machining. The object of this work is making summary of using measuring probes, description of the probes working principles and their division by construction and usage. The practical part of this work deals with creation of measuring cycles in softwaru Productivity+ and their implementation to machining cycles in MCV 1210. In the last part, two testing workpieces were created and the economic evaluation of introduction of the probes into machining process was performed.
538

Návrh progresivní technologie výroby tělesa šoupátka / Advanced technology project of valve body

Štábl, Martin January 2011 (has links)
This diploma work is dealing with the progressive production technology proposal of the valve body type S43 components. This is the high-pressure valve for the classical power supply. Here in the work is described the structural design of the valves, the material of the valve body and its machinability. Following an analysis of the existing production technology is the new production technology proposal for this part. All is designed with regards to the business possibilities of the Armaturka Vranová Lhota company. In conclusion of the work is presented the technical economic evaluation of both the existing and the proposed manufacturing technology.
539

Moderní řezné nástroje pro zapichování a upichování / Modern cutting tools for grooving and cutting-off

Matoušek, Jan January 2015 (has links)
The thesis in question deals with the influence of geometry of the cutting tool with a non-null angle r and of the cutting conditions on change of cutting tool’s overall deformation during the process of cutting-off and grooving. When conducting the experiments the loading of cutting tool was measured, there was created a simple 3D model of the cutting tool based on measured data, the deformation analysis of the cutting tool by the simulation programme ANSYS was performed and on the grounds of established facts there was made a conclusion on attributes of the cutting tool during the process of cutting-off and grooving.
540

Zavedení systému kontroly opotřebení při vrtání a řezání závitů do strojních dílů / Establishment of a wear control system for drilling and tapping when machining parts

Fortunet, Charles January 2014 (has links)
The topic of this thesis is divided in two main parts. The first is about the “tool/workpiece pair” method and the second is related to wear monitoring. The entire project will be about drilling and tapping operations done in SNECMA Vernon. In fact, the part is very expensive so they have to be closely controlled to avoid a maximum scrap pieces. Two software will be used to control it. Firstly, the “tool/workpiece pair” will be done through AMC3 (software developed at the ENSAM). And secondly the wear monitoring will be ensured by the software CTM Visu (developed by ARTIS). My task will be to learn how to use those software and then to implement them in the company.

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