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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.
151

Zpracování DPS silových a datových rozvodů pro historickou a památkově chráněnou budovu / Creation of Documentation for construction of power and data wiring for a historical and a listed building

Nestrojil, Martin January 2018 (has links)
This thesis is describing DPS power and data circuits installations for a historical listed building. Firstly, the theory describes requirements for architects and designs, the types of designs, the laws and directives. This part also contains instructions on how to lay the circuits, how to create environmental report and other topics closely related to design and architecture. Secondly, there is description of the design of the power and data installations for the building. The third practical section contains full project design documentation for power and data circuits for this building including technical drawing, environmental report, ground plans of the building, drawings of switchboards and block drawings. The outcome of this report is to present the theory and then create all relevant documentation for this historical building.
152

Technologie jednotné podpory multimediálních služeb v heterogenních sítích / Technology for comprehensive support of multimedia services in heterogeneous networks

Dosoudil, Petr January 2014 (has links)
The theses explains the Evolution Packet System (EPS) and subsystem IP Multimedia Subsystem (IMS). It also informs how these systems cooperate and through which interfaces the main data and signals between these two technologies are transfered. The thesis includes practical section, in which installation and configuration of sections of the IMS system including its "core", and application and medial server. For verification of the functionality of the system, two dissimilar clients are installed, and emulator WAN is applied for simulation of Internet. The product of the theses is the design of the laboratory exercise drafted in such a way that it can be solved by students less knowledgeable of the issues.
153

The impact of dividend policy on shareholders' wealth : evidence from the Vector Error Correction Model

Mvita, Mpinda Freddy 18 July 2013 (has links)
Dividend policy is widely researched in financial management, but determining whether it affects the market price per share is difficult. There has been much published on the subject, which presented theories such as the Modigliani, Miller, Gordon, Lintner, Walter and Richardson propositions and the relevance and irrelevance theories. However, little research has been done on the impact of dividend policy on shareholders’ wealth while considering the short- and long-run effects. The Vector Error Correction Model (VECM) was used to describe the short-run and long-run dynamics or the adjustment of the cointegrated variables towards their equilibrium values in South Africa. This study attempts to explain the effect of dividend policy on the market price per share. A sample of 46 companies listed on the Johannesburg Securities Exchange (JSE) was selected for the period 1995-2010. Three variables were used, namely the market price per share, the dividend per share and the earnings per share. The market price per share was used as a proxy in measuring shareholders’ wealth and the dividend per share was used as a proxy in measuring the dividend policy. Fixed and random effects models were applied to panel data to determine the relation between dividend policy and market price per share. The fixed effects method was used to control the stable characteristics of the companies over a fixed period. The random effects model was applied when the companies’ characteristics differed. Results for both models indicated that dividend yield is positively related to market price per share, while earnings per share do not have a significant impact on the market price per share. To test the strength of the long-run relationship, the VECM was applied. The coefficient for dividend per share in the co-integrating equation was positive, while the coefficient for earnings per share was negative. This confirms previous research findings. The results suggest that there is a long-run relationship between dividend per share and market price per share. The Granger causality test indicates there is bi-directional Granger causality between market price per share and dividend per share in South Africa. Therefore dividend policy does have a significant long-run impact on the share price and therefore provides a signal about the company’s financial success. / Dissertation (MCom)--University of Pretoria, 2012. / Financial Management / Unrestricted
154

Grundisolering för flerbostadshus : Jämförelse av cellglas och cellplast avseende energieffektivisering, ekonomiska aspekter och miljöpåverkan

Akhras, Samir, Arab, Mustafa, Yasin, Ahmed January 2023 (has links)
Purpose: This project compares two foundation insulation materials: cellular plastic and cellular glass. Currently, cellular plastic is the most used material for foundation insulation. While cellular glass is not widely utilized. Its disadvantage lies in its higher cost, which makes contractors prefer the cheaper alternative, cellular plastic. Cellular glass exhibits exceptional properties, including its notable attributes of high load-bearing capacity and superior moisture resistance. The aim of this study is to demonstrate how material savings can be achieved by using cellular glass instead of cellular plastic in the load-bearing parts of the foundation. In addition to cost savings, the study also includes the analysis of carbon dioxide emissions during the production of these materials and specific heat losses through the material. Method: To facilitate understanding of the study, two different buildings were visualized: a two-story building and a seven-story building. The choice of different building sizes aimed to investigate how different loads on foundation insulation affect insulation material costs, carbon dioxide emissions, and the heating requirements of the buildings. Revit and AutoCAD were used for modelling and visualization. Flixo and manual calculations were employed for energy calculations, while manual calculations were used for structural calculations. One Click LCA Software was used to determine the carbon dioxide emissions for the different foundation insulation scenarios. Results: The study suggests that for buildings with lighter loads, cellular plastic is a cost-effective choice, while a hybrid insulation approach combining cellular glass and cellular plastic is the best option considering environmental factors. However, for buildings with higher loads, cellular glass outperforms cellular plastic both in terms of economics and the environment. Nonetheless, a combination of cellular glass and cellular plastic remains the most favourable choice among the three scenarios, as energy losses are approximately the same due to the similar thermal conductivity values of these materials. Conclusion: Hybrid insulation proves to be the most advantageous option in terms of both the environment and economics for both types of buildings studied: the two-story residential building and the seven-story residential building. By using cellular glass F for the load-bearing structures and cellular plastic EPS S60 for the ground slab, effective insulation is achieved. The use of cellular glass F results in material savings, such as cellular plastic XPS 700, which has half the load-bearing capacity of cellular glass F. Additionally, reducing the use of extra concrete for load-bearing foundation constructions decreases the load on the foundation insulation material.
155

Dimensionering av platta på mark : En jämförelse mellan hand- och datorberäkningar

Dimashki, Alba January 2022 (has links)
The digital revolution has introduced several tools for structural engineers in the form of computer programs. These computer tools have partly transformed the role of structural engineers from their performing manual calculations to using different computer programs, evaluating the results, and checking codes.  Advanced computer-based calculation programs are often relied on when dimensioning structural parts. However, these are associated with certain consequences, especially when using black box software, which increases the need for an estimated model.  The purpose of this paper is to examine how the design of a concrete slab is estimated and how the results of such an estimate calculation relate to the results from computer calculations. The research method involves three main steps: gathering facts from references to learn how to design a concrete slab; developing a calculation model; and learning how to use PEPS, which is a type of black box software for performing calculations. In the analysis, PEPS is compared with manual calculations and the following conclusions are drawn based on the results: The estimate dimensioning of an edge-stiffened concrete slab can be simplified by using the equilibrium equation based on the edge beam. Results from this simplified method will differ from results produced by the computer program.  Simplified calculations are used to check the reasonableness of the PEPS results: Although PEPS indicates the cause of the bearing capacity of the concrete slab, the program fails to demonstrate how the results are calculated. / Den digitala revolutionen har fått till följd att det utvecklats en mängd olika datorverktyg som konstruktörer använder i konstruktionsarbetet. Dessa datorverktyg har förändrat konstruktörens roll från att använda handberäkningar till att använda olika dataprogram som hjälper till med utvärdering av resultat och kontroll av koder.  Vid dimensionering av bärverksdelar är det vanligt förekommande att i hög grad förlita sig på avancerade datorbaserade beräkningsprogram. Det finns dock konsekvenser med det, särskilt vid användning av blackbox-mjukvaror, vilket gör att behovet av överslagsberäkning ökar. För att undvika inkorrekt konstruktionsdesign behöver konstruktörer därmed ett sätt att kunna kontrollera rimligheten av de resultat som framkommer med hjälp av dataprogram. Syftet med detta arbete är att undersöka hur konstruktionen platta på mark kan överslagdimensioneras, samt undersöka hur resultaten av sådan överslagsdimensionering förhåller sig till resultat från datorberäkningar med etablerade mjukvaror. Metoden innehåller tre huvudmoment: 1) genomförandet av en litteraturstudie för att lära sig handberäkna grundplattor, 2) framtagningen av en beräkningsmodell för överslagsberäkning samt 3) lära sig använda PEPS som är ett beräkningsprogram som kan användas vid dimensionering av betongplatta. Programmet verkar vara en blackbox-mjukvara. I resultat- och analysdelen jämförs PEPS med handberäkningar och följande slutsatser dras utifrån resultaten: En överslagsdimensionering av kantförstyvad platta på mark kan utföras med hjälp av jämviktsekvation baserad på kantbalken. Resultaten från denna förenklade överlagsmetod skiljer sig från resultaten i själva PEPS programmet. Överslagsberäkningar bör användas för att kontrollera rimligheten för PEPS resultaten. PEPS visar orsaken till bärförmågan i grundplattor, däremot visar programmet inte hur resultaten räknas fram.  Ökningen av bärförmågan hos platta på mark kan ske på olika sätt beroende på lasttyp (linje- och punktlast) samt vilken placering denna last har. Genom att ha en bättre förståelse för konstruktionens verkningssätt är det möjligt att designa platta på mark på ett mer materialeffektivt sätt.
156

Road Feedback in a Steer-by-Wire System for a Passenger Car : enhancing the feeling of being connected

Finne, Alice, Ström, Louise January 2022 (has links)
Road feedback is an essential part of the driving experience, representing a connection betweenthe driver and the vehicle motion. Road feedback in a steer-by-wire system must berecreated and transferred to the driver through a feedback motor mounted on the steeringwheel. This project aimed to implement a function in the feedback motor control with thepurpose of giving the driver road feedback. The function should enhance the drivers trustand confidence in the steering system. Specifically, the function should provide the driverwith a feeling of being connected to the vehicle. A pre-study on the subject of steering feel was made as well as an interview study, whichresulted in a list of hypotheses. The hypotheses became a basis for generating conceptideas, together with measurement data of vehicle network signals for different drivingscenarios. Two different functions were then modelled and implemented in MathWorksSimulink. Function 1 models force components acting on the front road wheels in longitudinal,lateral and vertical direction. The forces result in a torque contribution fromeach dimension that acts around the steering axis and represents a reaction in the steeringsystem due to road disturbances. The torque is then translated to a steering wheel torque.Function 2 strives to capture road surface roughness through the high frequency informationin the steering rack motor torque. Three different road surfaces were studied; smoothasphalt, rough asphalt and gravel road. A test rig was used in order to verify the behaviour of the functions. The final step of theproject was to implement the functions in a test vehicle, where they could be further tunedand evaluated. The force component models of Function 1 captured different types of roadfeedback which were evaluated separately by timing, authenticity and desirability. Theresult of this evaluation was positive considering them separately. When the models werecombined it resulted in an unwanted behaviour. Function 2 gave torque feedback that feltauthentic and natural, especially for the gravel road case. However, it was more difficult todistinguish different asphalt types. The conclusion was that neither Function 1 nor 2 couldbe approved as finished functions, however both are considered as interesting concepts forfurther development. Fully steer-by-wire steering transmissions have now been approved for usage. This meansthat one of the remaining challenges for implementing steer-by-wire cars on today’s marketis the subjective views from the customers. Function 1 and 2 could be a way to providethe drivers with trust towards the steering, and at the same time, enhance the drivingexperience. / <p>The presentation was held at ACAS at Linköping University. The presentation included a summary and learnings from the project. A short demonstration was performed using a test-rig consisting of a steering wheel, a feedback motor and a control unit. </p>
157

Analysis of Biofilm Remediation Capacity for Octenyl Succinic Anhydride (OSA), a Bioactive Food Starch Modifier Compound

Borglin, Matthew R 01 June 2020 (has links) (PDF)
Matthew R. Borglin This thesis demonstrates efficacy of Octenyl Succinic Anhydride (OSA), as a biofilm sanitizer. Biofilms allow bacteria to adhere to solid surfaces with the use of excreted polymeric compounds. For example, surfaces found in food production or processing facilities such as the interior of a raw milk holding tank, are some of the most susceptible to biofilm contamination. When present, biofilms can cause a variety of negative effects, which include; reduction of product shelf life, corrosion, and outbreaks of foodborne illnesses. The close association of biofilms with the majority of foodborne illness cases led the US Environmental Protection Agency (EPA) to create a new category of sanitizer specifically designed for treatment of mature biofilms. The efficacy of sanitizers in this new regulatory category is determined by the EPA protocols MB-19 and MB-20. The EPA’s protocols outline methods for cultivating, treating, and measuring effects on Pseudomonas aeruginosa biofilms in a continuous flow stir bar bioreactor. Biofilm modification by OSA was verified by the presence of octenyl esters on OSA treated biofilms with single point Raman spectrophotometry. OSA modified biofilm’s antimicrobial properties were first investigated with crystal violet staining in 96-well microtiter plates with inconclusive results. However, effective antimicrobial properties where apparent when using the CDC Biofilm Reactor. OSA treatments consistently returned a 6-log CFU/coupon reduction in biomass compared to controls. Inhibition of planktonic and/or biofilm regrowth was demonstrated using the 96-well plate methodology. This thesis demonstrated the effectiveness of OSA chemical esterification reaction as a biofilm treatment. In doing so, this work suggests a new approach for biofilm remediation by chemically modifying the structural components of biofilm.
158

Etude comparative des matériaux de garnissage dans les réacteurs de filtration pour l’assainissement non collectif / Comparative study of packing materials of filtration reactors for on-site wastewater treatment

Wang, Chen 14 September 2015 (has links)
L'assainissement non collectif concerne 12 à 15 millions de personnes en France. La filière classique de ce mode d’assainissement se compose généralement d'un prétraitement anaérobie par une fosse septique recevant l’ensemble des eaux usées domestiques suivi d’un système d’infiltration dans le sol ou d’un filtre à sable. Le filtre à sable vertical drainé met à profit le pourvoir épuratoire qui est principalement lié à la présence d’une biomasse sous forme d’un biofilm. Cette dynamique de la croissance de la biomasse ou du biofilm est soumise à l’impact de la nature de matériaux filtrants. L’écoulement insaturé dans ces systèmes conditionne également cette croissance du biofilm. Dans ce contexte, l'objectif du travail de la thèse est d’appréhender les mécanismes mis en jeu et particulièrement l’impact des matériaux dans le fonctionnement des filtres en comparant notamment deux types de matériaux: les sables de rivière et les agrégats concassés. Pour cela, une étude expérimental sur une unité pilote composé des réacteurs de filtration du diamètre de 30cm et différents épaisseurs de garnissage (15, 30 et 70cm) a été construite. Les réacteurs garnis de deux sables roulés et deux agrégats concassés, sont alimentés en effluent septique avec une charge volumique 12cm/jour par 10 bâchés par jour. Suite des matériaux, une étude de la performance épuratoire avec le suivi des composants biochimiques de la biomasse totale et de la matrice extracellulaire du biofilm est réalisée en comparant notamment les deux types de matériaux filtrants. / The onsite wastewater treatment systems concern 12 to 15 million of people in France. The treatment plant is generally composed by a septic tank as pretreatment, followed by soil infiltration field or sand filtration bed. The vertical drained sand filter provides the purification capacity thanks to the presence of a biomass in form of the biofilm. The dynamic of the biomass growth or the biofilm development is under the impact of filter materials’ nature. In this context, the objective of this work is to understand the mechanisms involved and especially the impact of medium in the functioning of the filtration reactor by comparing two types of packing materials: river sands and crushed aggregates. For this purpose, an experimental study is conducted with pilot unity composed by filtration reactors of 30cm of diameter and different packing thicknesses (15, 30 and 70cm). The reactors packed with two river sands and two crushed aggregates are fed with septic effluent with a volumic hydraulic charge of 12cm/day by 10 batches per day. Based on a characterization of materials, a study of purification performance with biochemical components monitoring of the total biomass and the extracellular matrix of the biofilm is realized by comparing two types of filter materials. The purification performance has presented similar efficiencies of particulates and organic matters removals by fine river sand and fine crushed aggregate. The nitrogen pollutants removals are more effective in the fine river sand which presents the finest granulometry with an alternative of aerobic and anoxic phases along the reactor depth and with a biomass more abundant. The distribution and the quality of the total biomass and the extracellular matrix differentiate between the river sand and the crushed aggregates. As the reference material, the fine river sand presented an earlier stabilization of total biomass growth with a less important production of extracellular exudates compared to the crushed aggregates. The origin of impacts brought by the crushed aggregates might be due to the higher fine particles content which created microenvironments poor in substrates or in oxygen and also due to a more heterogeneous mineralogy. The extracellular components of highest percentage in the biofilm of crushed aggregate are polysaccharides type substances.
159

The Impact of Insulation Materials on a Climate Declaration : A Study of a Swedish Preschool

Hallkvist, Isabelle, Nilsson, Elin January 2021 (has links)
To reach the net-zero carbon goal by 2045, the Swedish government want to push the building and construction sector to lower their greenhouse gas emissions. This push is performed by implementing a law requiring building developers to perform a climate declaration over greenhouse gas emissions, to receive a building’s final clearance. The climate declaration is limited to only include emissions from material extraction until completed building. However, there is a varying knowledge level in the industry regarding how to perform a climate declaration as well as how different materials impact the result. Therefore, this study aims to bring clarity concerning the topic, by investigating where the major and minor climate impacts occur in a building process. Additionally, the impact of different insulations materials and how they influence the result of a climate declaration is studied. To answer the research questions, a climate declaration is performed on a Swedish preschool. The insulation material in the building is altered between glass wool, stone wool, cellulose fibre, foam glass, and polystyrene insulation in different scenarios to see how it impacts the result. The stone wool scenarios use both carbon neutral and non-carbon neutral insulation. Cellulose fibre uses both loose wool with data from an EPD and board insulation with data from Boverket’s climate database in the scenarios. The major climate impact derives from the product stage (A1–A3), meaning material selection have a significant impact on the climate declaration result. The building element with the highest climate impact is the inner walls followed by the foundation, while the floor construction, roof and outer walls have the lowest climate impact. On a material level, plaster board, building plywood and concrete have the highest climate impact in the reference building. The cedar panel have the lowest climate impact and is the only carbon negative material in the reference building. However, this is due to different assumptions made in the climate impact data concerning the binding of carbon in organic materials. The results showed that the insulation material with the highest climate impact is non-carbon neutral stone wool that is 16 % higher than the original construction with glass wool, while loose cellulose wool has the lowest climate impact. The climate impact from the scenario with non-carbon neutral stone wool in the wall and roof construction is 33 % higher compared to the corresponding loose cellulose wool scenario. The scenario with the lowest climate impact, with loose cellulose wool, is approximately 13 % lower than the corresponding glass wool scenario. The carbon neutral stone wool scenario has a similar result to glass wool. Foam glass has a 9.5 % higher climate impact compared to polystyrene insulation in the foundation. Regarding the selection of insulation material, it influences the climate declaration by changing the climate impact. The influence derives from a combination of climate impact per unit and material quantity used in the building. The material quantity is partly dependant on the thermal conductivity (λ-value) of the insulation material. The climate declaration shows a limited view of a building’s environmental impact for a limited part of its lifecycle. Therefore, we would recommend additional lifecycle stages and environmental impacts to be part of the climate declaration in the future, as a means to avoid suboptimization and unintentional problem shifting. / För att nå klimatneutralitetsmålet 2045 vill den svenska regeringen driva bygg- och fastighetssektorn till att sänka sina växthusgasutsläpp. Denna insats utförs genom att införa en lag som kräver att byggherrar utför en klimatdeklaration över växthusgasutsläpp för att få ett slutbesked för byggnaden. Klimatdeklarationen är begränsad till att endast omfatta utsläpp från materialutvinning fram till färdig byggnad. Det finns dock en varierande kunskapsnivå i branschen om hur en klimatdeklaration utförs samt hur olika material påverkar resultatet. Därför syftar denna studie till att ge klarhet angående ämnet genom att undersöka var de större och mindre inflytandena på klimatpåverkan förekommer i en byggprocess. Dessutom studeras effekterna av olika isoleringsmaterial och hur de påverkar resultatet av en klimatdeklaration. För att besvara frågeställningarna utförs en klimatdeklaration på en svensk förskola. Isoleringsmaterialet i byggnaden ändras mellan glasull, stenull, cellulosafiber, skumglas och cellplast i olika scenarier för att se hur det påverkar resultatet. I stenullscenarierna används både koldioxidneutral och icke-koldioxidneutral isolering. Cellulosafibrer använder både lösull med data från en EPD och skivisolering med data från Boverkets klimatdatabas i scenarierna. Den största klimatpåverkan kommer från produktstadiet (A1–A3), vilket innebär att materialvalet har en betydande inverkan på klimatdeklarationsresultatet. Byggnadselementet med störst klimatpåverkan är innerväggarna följt av grunden, medan bjälklaget, taket och ytterväggarna har lägst klimatpåverkan. På materialnivå har gipsskivor, plywood och betong den högsta klimatpåverkan i referensbyggnaden. Cederpanelen har lägst klimatpåverkan och är det enda koldioxidnegativa materialet i referensbyggnaden. Detta beror dock på olika antaganden i klimatpåverkan angående bindningen av kol i organiska material. Resultaten visade att isoleringsmaterialet med den högsta klimatpåverkan är icke-koldioxidneutral stenull, som är 16 % högre än originalkonstruktionen med glasull, medan lös cellulosaull har lägst klimatpåverkan. Klimatpåverkan från scenariot med icke koldioxidneutral stenull i vägg- och takkonstruktion är 33 % högre jämfört med motsvarande scenario med lös cellulosaull. Scenariot med lägst klimatpåverkan, med lös cellulosaull, är cirka 13 % lägre än motsvarande glasullscenario. Det koldioxidneutrala stenullscenariot har ett liknande resultat som glasull. Skumglas har 9,5 % högre klimatpåverkan jämfört med cellplasten i grunden. När det gäller valet av isoleringsmaterial påverkar det klimatdeklarationen genom att förändra klimatpåverkan. Påverkan härstammar från en kombination av klimatpåverkan per enhet och mängden material som används i byggnaden. Mängden material beror delvis på isoleringsmaterialets värmekonduktivitet (λ-värde). Klimatdeklarationen visar en begränsad bild av en byggnads miljöpåverkan under en begränsad del av dess livscykel. Därför rekommenderar vi att ytterligare livscykelstadier och miljöindikatorer ingår i klimatdeklarationen i framtiden, för att undvika suboptimeringar och oavsiktliga problembyten.
160

Podpora výuky systémů elektrické požární signalizace / Support for instruction in electric fire alarm systems

Macinka, Jiří January 2008 (has links)
The master’s thesis „Support for instruction in electric fire alarm system” describes principles and engineering solution of electric fire alarm system. It is background for activity task about EPS for students in VUT in Brno. It illustrates how to act on this task and configuration fire panel and components EPS with the support of software FSP 5000. The practice contains proposal EPS with support in fire system designer.

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