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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.
81

Uticaj sindroma gornjeg otvora grudnog koša na spavanje / Impact of Thoracic Outlet Syndrome on Sleep

Milenović Nataša 09 September 2016 (has links)
<p>Uvod - Etiologija sindroma gornjeg otvora grudnog ko&scaron;a (thoracic outlet syndrome- TOS) je udruženost vi&scaron;e faktora koji su posledica naru&scaron;avanja anatomsko-topografskih odnosa u nivou gornjeg otvora grudnog ko&scaron;a: kostoklavikularnog prostora, prednjeg skalenskog otvora, kao i same mehanike rebarnih zglobova i hrskavica, koji dovode do suženja prostora kroz koje prolaze neurovaskularne strukture, njihove kompresije, a samim tim i iritacije neurovaskularnih struktura. Sindrom gornjeg otvora grudnog ko&scaron;a je kompleks simptoma uzrokovanih kompresijom brahijalnog spleta, vene subklavije, arterije subklavije i simpatičkih vlakana, koji karakteri&scaron;u bol, parestezije, mi&scaron;ićna slabost i osećaj nelagodnosti u ruci/rukama koji se pojačava podizanjem ruke/ruku ili prekomernim pokretima glave i vrata, te dovode do smanjenja funkcionalne sposobnosti ruke/ruku i pote&scaron;koća u obavljanju svakodnevnih aktivnosti. Pored toga imaju često izraženu tahikardiju, osećaj stezanja u grudima, glavobolju, vrtoglavicu, zujanje u u&scaron;ima. Navedene tegobe su izraženije ponekad noću i dovode do poremećaja spavanja (problemi usnivanja, hrkanje, ka&scaron;ljanje, osećaj toplo/hladno, apnea, poremećaj dnevno/noćnog ritma- hronotipizacija, itd). Kao posledica lo&scaron;eg spavanja moguća je pojava depresivnih simptoma. U raspoloživoj literaturi, spavanje i kvalitet spavanja se uglavnom posmatraju kroz prizmu drugih bolesti i stanja. Materijal i metode - Istraživanjem je obuhvaćeno ukupno 181 (sto osam deset jedna) osoba. Od tog broja 53 mu&scaron;karca i 128 žena. Test grupu sačinjavalo je 82 ispitanika sa dijagnostikovanim TOS, a 99 zdravih osoba/osoba oba pola koji nemaju simptomatologiju TOS, je predstavljalo kontrolnu grupu. Grupe su bile ujednačene po polu i starosti (od 18 do 65). Tokom studije ispitanici su podvrgnuti kliničkom pregledu &ndash; fizikalnom i neurolo&scaron;kom pregledu. Pregled je podrazumevao pregled posture obolelog (posmatranje mi&scaron;ića regije vrata, ramena i ruku- trofika, tonus, konzistencija, mobilnost i kontraktilnost), posmatranje promena na koži (sa posebnim osvrtom na promene boje kože, trofičkih promena kože i noktiju i temperature kože ruku - &scaron;aka), testiranje refleksa, ispitivanje senzibiliteta u regijama inervacije odgovarajućih spinalnih korenova brahijalnog spleta. Takođe vr&scaron;ena je analiza stanja uhranjenosti (telesna visina, telesna masa, indeks telesne mase) i izvođenje provokativnih testova (Adson manevar, Rus test, Halsted test, Elvi test i Kostoklavikularni test). Kao deo ispitivanja obavljeno je i radiolo&scaron;ko snimanje vratne kičme kao i pregled oscilografom. Ispitanici su imali za zadatak da ispune sledeće upitnike: Upitnik o nesposobnosti ruke, ramena i &scaron;ake (DASH), Pitsbur&scaron;ki indeks kvaliteta spavanja (PSQI), Upitnik o hronotipizaciji (MEQ), Bekov upitnik o depresiji (BDI II). Na kraju ispitanici su davali odgovore na pitanja iz vodiča za istraživača sastavljenog sa ciljem evaluacije različitih aspekata spavanja. Rezultati - Rezultati su pokazali da su upotrebljene skale dale zadovoljavajuću pouzdanost. Pokazalo se da osobe sa dijagnozom TOS pored bogate simptomatologije imaju jo&scaron; i probleme sa spavanjem. Analizom rezultata do&scaron;lo se do zaključka da osobe sa dijagnozom TOS su starije, imaju vi&scaron;e problema sa spavanjem i veću nesposobnost ruke, ramena i &scaron;ake. Nije se pokazala razlika u hronotipizaciji kod osoba sa TOS u odnosu na kontrolnu grupu. Takođe može se zaključiti da osobe koje imaju izraženu nesposobnost ruku, ramena i &scaron;ake imaju značajno veću &scaron;ansu da imaju sindrom gornjeg otvora grudnog ko&scaron;a. Ove osobe pri tom imaju i veću &scaron;ansu da razviju depresiju i poremećaj spavanja, te se zaključuje da ova dva parametra svoj uticaj na TOS ostvaruju preko problema sa funkcionisanjem ruke, ramena i &scaron;ake. Dobar prediktor za postavljanje dijagnoze TOS može biti testiranje osoba DASH skalom. Zaključak - Rezultati studije mogu biti putokaz daljim istraživanjima, koja bi otvorila vrata formiranju protokola i opservaciji kvaliteta života osoba sa sindroma gornjeg otvora grudnog ko&scaron;a, sa posebnim osvrtom na poremećaje spavanja.</p> / <p>Etiology of thoracic outlet syndrome (TOS) is an association of several factors which are the result of disruption in the anatomical-topographical relations, in the level of superior thoracic aperture: costoclavicular space, anterior scalene aperture, as well as the mechanics of rib joints and cartilage, causing narrowing of space through which the neurovascular structures pass, their compression, and thus the irritation of neurovascular structures. Thoracic outlet syndrome is a complex of symptoms caused by the compression of the brachial plexus, subclavian vein, subclavian artery and sympathetic fibres, which is characterized by pain, parasthesias, muscle weakness and a feeling of discomfort in the arm / arms, which increases with raising the arm/arms or by excessive head and neck movements leading to a reduction of functional capabilities of the hands / arms and difficulties in everyday activities. In addition, patients often have expressed tachycardia, feeling of tightness in the chest, headache, dizziness, tinnitus. These problems are more pronounced at night and sometimes lead to sleep disorders (difficulty in falling asleep, snoring, coughing, feeling hot/cold, apnea, day/night rhythm disorder - Morningness/Eveningness disorder, etc.). As a result of poor sleeping depressive symptoms may occur. In the available bibliography, sleep and quality of sleep are mainly viewed through other diseases and conditions. The study included a total number of 181 (one hundred eighty one) people. Out of that 53 men and 128 women. The test group consisted of 82 patients diagnosed with TOS, and 99 healthy persons of both genders who had no symptoms of TOS, and constitute the control group. Groups were equalled by gender and age (18 to 65). Throughout the study subjects underwent clinical examination - both physical and neurological. This included an assessment of posture of the patient (observation of muscles in region of the neck, shoulders and arms - trophic, muscle tone, consistency, mobility and contractility), observation of changes on the skin (with a special emphasis on skin colour changes, trophic changes of the skin, nails and skin temperature of arms - hands), reflex testing, sensitivity testing in regions of innervations which correspond to spinal roots of the brachial plexus. Moreover, an analysis was conducted on the body composition analysis (body height, body weight, body mass index) as well as provocative tests (Adson manoeuvre, the Roos test, Halstead test, Elvy test and Costoclavicular test). Radiology scan of the cervical spine as well as oscillograph testing was conducted as a part of the test. The subjects were asked to fulfil the following questionnaires: Questionnaire on Disabilities of the Arm, Shoulder and Hand (DASH), Pittsburgh Sleep Quality Index (PSQI), The Morningness / Eveningness Questionnaire (MEQ), Beck Questionnaire on Depression (BDI II). Finally the subjects answered questions that researcher had drawn up in order to evaluate different aspects of sleep. The results showed that the scales used were reliable. It proved that persons diagnosed with TOS in addition to numerous symptoms also had problems with sleep. By analyzing the results it was concluded that people diagnosed with TOS are older, have more problems with sleep and greater disability of arms, shoulders and hands. There was no difference in Morningness/Eveningness type in patients with TOS in comparison to the control group. It can also be concluded that people who have pronounced disability of arms, shoulders and hands have a significantly greater chance of having thoracic outlet syndrome. These persons are more likely to develop depression and sleep disorders therefore those two entities impact TOS through the problems with the functioning of the arms, shoulders and hands. A good predictor in diagnosis of TOS may be testing people with DASH scale. The study findings can serve as a guideline for further research, opening the door into forming protocols and observation of the quality of life of people with the thoracic outlet syndrome, with special emphasis on sleep disorders.</p>
82

[en] STARTUP FLOW OF GELLED CRUDES AFTER A SHUTDOWN: COMPARISON BETWEEN SIMULATIONS AND EXPERIMENTAL DATA / [pt] REINÍCIO DE ESCOAMENTO DE ÓLEOS GELIFICADOS APÓS PARADA DE PRODUÇÃO: COMPARAÇÃO ENTRE SIMULAÇÕES E DADOS EXPERIMENTAIS

DENISE DINIZ SOUTO LIMA 14 May 2019 (has links)
[pt] Uma preocupação constante referente às operações de reinício de escoamento em poços produtores de óleo é a previsibilidade da mínima pressão necessária para iniciar o fluxo após uma parada de produção. Tal pressão se refere àquela que promove tensões de cisalhamento junto à parede do duto que superam o valor da tensão limite de escoamento do referido fluido. A necessidade de desenvolvimento de diferentes tipos de campos de petróleo ao redor do mundo tem promovido discussões sobre importantes aspectos de garantia de escoamento dos fluidos, especialmente em cenários de produção em águas ultra-profundas. Nesses casos, quando o fluido apresenta valores elevados para a temperatura mínima de aparecimento de cristais (TIAC) ou ainda para a tensão limite de escoamento, o procedimento de repartida de poço após uma parada de produção pode representar um problema. Em geral, os modelos tixotrópicos utilizados na avaliação de reinício do escoamento são definidos por uma equação constitutiva baseada no modelo de Bingham, na qual a tensão de cisalhamento depende do grau de estruturação do fluido no interior do duto, representado por um parâmetro adimensional positivo (lambda). A evolução deste parâmetro no tempo é governada por uma equação constitutiva que considera um termo de construção e um termo de quebra do gel. Este trabalho tem como principal objetivo avaliar o comportamento do reinício da produção através da variação destes parâmetros/termos segundo modelos tixotrópicos específicos (Houska e SMT) e a representatividade dos resultados de simulação quando comparados aos dados experimentais. / [en] The main concern regarding to the restart operations for production wells in oil and gas systems is the forecast of minimum pressure needed to overcome the gel strength, i.e. the pressure which generates a wall stress higher than the yield stress of the gelled oil. The petroleum accumulations around the world have raised big issues regarding flow assurance aspects, especially in some ultra-deep water scenarios. In these cases, when the oil presents unusual high values for the Wax Appearance Temperature (WAT) and even for the yield stress, the flow restart procedure can be an issue, after shutdown times of the oil production. Usually, the thixotropic models applied for start-up flow are defined by a Bingham-like stress equation whose yield stress depends on a structure parameter (lambda), following Houska assumptions. This parameter is a non-negative scalar number that represents the structuring level of the material inside the pipeline. The structure parameter is governed by an evolution equation that considers a build-up term and a breakdown term. The main objective of this work is to evaluate the relationship between the parameters of the constitutive equations for Houska and SMT models (dimensionless coefficients of the evolution equations for the structure parameter) and the representativeness of the simulation results obtained by these models, regarding times for the production stabilization after a restart, delay times and yield stresses, when compared to experimental data.
83

Ring Oscillator Based Temperature Sensor

Walvekar, Trupti 07 1900 (has links) (PDF)
The temperature sensor design discussed in this thesis, is meant mainly to monitor temperature at power outlets. Current variations in power cords have a direct impact on the surrounding temperature. Sensing these variations ,enables us to take necessary measures to prevent any hazards due to temperature rise. Thus, for this application we require a sensor with a moderate temperature error (_10C) over a sensing range of -200C to 1500C. Low power consumption and simple digitizing scheme alleviate measurement errors due to self heating effects of the sensor. A current starved inverter based ring oscillator was chosen for the sensor design in 130nm technology. The inverter delay variation with temperature is used for sensing. Linearity and process invariancy of these characteristics are fundamental to the sensor design. We observed through simulations, and confirmed by mathematical analysis, that the sensing characteristics are governed by bias current dependence on temperature. Control voltage for the bias circuitry of the oscillator determines current through the inverter stages. Hence, for linear sensing characteristics, a control voltage(Vc) just above the maximum threshold voltage of bias transistor is used. This enables generation of PTAT saturation current for current starved inverters, due to dominance of threshold voltage decrease with temperature over mobility decrease. I.Another limitation, process dependency of the sensing characteristics, was overcome through the proposed calibration based compensation technique. A changing Vc proportional to threshold voltage variation with process, process independent bias current and current temperature characteristics were obtained. This compensated for the process variation effects on frequency. Thus, a variable Vc was generated using a reference with low temperature sensitivity of 17.6_V=0C, and resistive divider combinations for various processes. Incorporating this compensation technique we achieved good linearity in sensor characteristics and a maximum temperature error of± 1.60C over the sensing range. The sensor consumes a low power of 0.29mW and also occupies minimal area.
84

Parní turbína v paroplynovém cyklu / Steam Turbine in the Combi Cycle

Filoušová, Natálie January 2017 (has links)
Diploma thesis named Steam turbine in the combi cycle deals with design of low pressure part of three-body turbine and it’s lateral outlet throat to the air condenser. Before the design itself, the thermal schema of entire turbine is calculated. Than follows the detail draft, the strength calculations are included as well. Turbine has any technological consumption of steam or any regenerativ consumption. Turbine will be suplly to Panama. The thesis includes following drawings: cut of flowing part, design of outlet throat and fixing of inner body in outer body of low pressure part. The diploma thesis is created for Doosan Škoda Power company.
85

Připojování fotovoltaických zdrojů k distribuční síti / Connecting of the Photovoltaic Power Sources to the Distibution Network

Ondroušek, Luděk January 2009 (has links)
This work is focused on the current issues, which are associated with the connection of fotovoltaic sources to the distribution grids. An example of these problems can be the connection of the bigger fotovoltaic power plant to the part of the grid with small short-circuit power. In consequence of this, it can happen that the quality parameters (voltage) of this grid are undesiderably influenced. Integral part of the connection procedure of the new sources to the grid is also a design and method of the power output, which is also part of this work.
86

Program pro návrh společných TV kabelových rozvodů / Program for design of CATV

Sedláček, Jan January 2010 (has links)
The main task of this master’s thesis is to create an interactive computer programme for the design of small and medium television cable circuits. The first part of this document describes main conceptions of a modification and a distribution of television signals. There are also introduced basic topologies of small and medium sized distribution networks, some passive and active elements in the circuit including their usage. There is also described an algorithm for calculation of circuit’s values. The second part contains a detailed description of created programme with all of its functions. A part of this document is made by a sample calculation of the four variants of circuit and its comparison with computer calculation. In suplement are included selected parts of source code.
87

Vodohospodářské řešení ochranné vodní nádrže v povodí Kobylího potoka / Water Management Solution of Retention Function of the Kobylí potok reservoir

Šourek, Jan January 2013 (has links)
The subject of the thesis is to design proposal protective water management solution reservoirs in the basin Kobylí potok. This thesis consist of the text, hydraulic calculation and graphic.
88

Stanovení kapacity rozstřikovacího uzávěru v podmínkách omezeného výtoku / Hollow cone valve capacity in the restricted outflow conditions

Nehudek, Adam January 2015 (has links)
The thesis aims to determine the influence partial or complete submerge of hollow cone valve by outflow on its capacity without space restrictions, by outflow into discharge chamber and by outflow into water tunnel of circular cross section. The valve capacity is for mutual comparability purposes usually characterized by discharge coefficient. Research works have been performed on a spatial hydraulic model of the valve with inlet diameter D = 67 mm and an apex angle of a cone 90°. Values of the discharge coefficient obtained from measurements were statistically analyzed. The dependence of discharge coefficient, expressed by energy head, on submerged level was approximated by an exponential function. Exponent value of this function express the dependance rate of valve capacity on downstream water level. This procedure didn’t demonstrate signifiant dependance downstream water level on hollow cone valve capacity, only on tests at outflow to water tunel showed a low increase in the discharge coefficient partly due to the influence of kinetic energy of the stream flowing out of the tunnel on the energy head and also due to underpressure. Independence of discharge coefficient value on valve head has been prooved for head greather than 232 mm. Also was defined 3 stages of interaction outflow jet from valve and downstream water, some of them may cause on real waterworks structures unfavorable situations (may affect excessive load on valve by pressure pulsations). The presented results allow better evaluation of bottom outlets capacity at higher water levels, when the valves are flooded. Significant effect of sufficient aeration (especially in long water tunnels) on valve capacity was also confirmed. Taking into account on the specifics of hollow jet valves and cone valves, it is possible to generalize some of this resultos on them as well.
89

Návrh malé vodní nádrže v malém povodí / Design of the multipurpose small water reservoir

Rumanová, Jana January 2016 (has links)
Master's thesis aims to design a small water reservoir. It is the dry water reservoir which is situated above a built-up area. The main function of this reservoir is a flood protection. Digital terrain model is created in a program BENTLEY MicroStation V8i – Power Civil. Focusing points in a data file are used in a process of creating of the DTM. Adjustments are done in AutoCAD. Particular hydro-technical calculations are calculated in a program Microsoft Excel. A program HEC-HMS is used for an assessment of a flood wave transformation and a program HEC-RAS is used for a water runoff simulation via emergency spillway.
90

Effekttoppskapning med styrsystem från Enequi : En analys av effektavgiftbesparing och produktprestanda / Peak power shaving with control system from Enequi : An analysis of power fee savings and product performance

Oskarsson, Ebba, Lönnqvist, Tim January 2024 (has links)
I takt med ökad elektrifiering i samhället står elnätet inför en problematik med kapacitetsbrist. Med anledning av detta finns ett behov av att utveckla en mer flexibel och effektiv användning av elnätet. En del i detta är införandet av effekttariffer, vilket ska skapa incitament för elkunder att sprida ut sin elanvändning och på så sätt avlasta elnätet. Företaget Enequi tillhandahåller ett system med smart styrning och batterilagring vilket kan utföra effekttoppskapning i syfte att reducera effektavgiften. I denna studie granskas två bostäder, belägna i Partille och Sollentuna, vilka båda har ett styrsystem från Enequi installerat. Syftet är att undersöka hur styrningen bidrar till en förändring i effektavgiften hos de båda bostäderna, samt att bedöma systemets prestanda. Resultatet från Partille visar att ägaren under de åtta månaderna systemet varit i drift sparar 259 kronor på effektavgiften, medan ägaren i Sollentuna under tolv månader sparar 865 kronor. Analysen av systemets prestanda visar också att systemet presterar mest optimalt när egenproducerad el är tillgänglig. Systemet bidrar till nätnytta genom att flytta lasten i bostaden från högt belastade timmar till lågt belastade. Brister som har identifierats i prestandan inkluderar problematik med förhöjda effektavgifter under vissa månader. Slutsatsen är att systemet presterar funktionellt trots vissa brister och att det är möjligt att göra besparingar på effektavgiften över tid.

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