• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 315
  • 52
  • 50
  • 30
  • 8
  • 6
  • 2
  • 1
  • 1
  • Tagged with
  • 466
  • 196
  • 98
  • 81
  • 55
  • 45
  • 45
  • 43
  • 39
  • 38
  • 37
  • 33
  • 31
  • 29
  • 29
  • 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.
311

Vytvoření předpokladů pro hodnocení vlastností vysokopevnostních betonů s využitím nedestruktivních metod zkoušení / Creating conditions for evaluation of high-strength concrete characteristics using non-destructive testing methods

Procházka, David Unknown Date (has links)
High-strength concrete (HSC) belongs in the recent years to frequently used types of concrete. It allows realization of static challenging structures and also shows due to its dense structure greater durability especially against aggressive media. Currently HSC construction realization abroad is not exceptional. It’s using in the Czech Republic is still limited. When realized, then in a small scale in civil engineering works. The realization of high-strength concrete structures is closely related with the concrete construction quality verification. Good efficiency of the quality control methods can provide non-destructive testing methods (NDT), especially when investigating strength of concrete built in structure. A lack on relevant data for non-destructive testing of HSC in technical and normative rules is to be considered as a significant deficiency. Evident for HSC generally is the lack in literature on deeper analysis of the factors affecting their non-destructive testing, as well a meaningful methodology or practically usable calibration relationships. HSC differs from ordinary concrete not only by used components, but also by more compact structure with different strength – elastic characteristics. Considering these differences, HSC strength prediction can not be performed by using calibration relationships developed for ordinary concrete. Moreover, the question is to what extent the current knowledge of the NDT results influencing factors can be considered as valid. The paper presents findings on the effects of the key factors affecting the measurement results of Schmidt hardness method and ultrasonic pulse method, including recommendations for the practical application of these methods. The problematic of static vs. dynamic modulus of elasticity was also solved. Calibration equations for predicting the compressive strength of HSC from the non-destructive testing parameter were elaborated, showing high cohesion among variables and practically usability.
312

Reologi på gelberedningar / Rheology on gel compositions

Eriksson, Anna, Andersson, Viktoria, Berezniak, Katrin, Hall, Markus, Håkanson, Victor, Biörs, Ida January 2016 (has links)
Konsistensen på en gel bestående av tvärbunden hyaluronsyra beror av tre faktorer: total koncentration hyaluronsyra, gelningsgrad och tvärbindningsdensitet. För att utföra detta projekt erhölls tre olika geler med olika tvärbindningsdensitet. Dessa geler späddes dels med lösning av fri, icke tvärbunden, HA från 100 % gelningsgrad till 90 % och 80 %. De olika gelningsgraderna späddes också med natriumkloridlösning från den totala koncentrationen HA, 35 mg HA/g gel, till 25 mg/g och 15 mg/g. Projekts huvudfråga är att kartlägga gelens reologiska egenkaper då både total koncentration HA och gelningsgrad varieras. För att kunna kartlägga detta har en reometer brukats där följande tre tester körts: tidssvep, frekvenssvep och amplitudsvep. Från erhållen data har sedan två parametrar som representerar gelkompositionernas viskösa egenskaper (G'') och elastiska egenskaper (G') observerats. Även mätning av extruderingskraft har genomförts för att dra vidare paralleller och slutsatser mellan extruderingskraften och de reoligiska egenskaperna. Ur resultaten ses att förlusttangenten tenderar att sjunka när gelningsgraden ökar, d.v.s. gelerna blir då mer viskösa och mindre elastiska. Förlusttangenten sjunker även vid ökande total koncentration HA vilket betyder att G’ ökar mer än G’’ i vardera punkt som gör att förlusttangenten minskar.Det gick även att avläsa att de viskösa egenskaperna i gelen ökar då total koncentration hyaluronsyra minskar samt att de viskösa egenskaperna i gelerna minskar vid en sjunkande gelningsgrad. Mellan gelningsgrad 90-100 % och total koncentration HA 25-35 mg HA/g har analyserna som gjorts i detta projekt gett följande slutsatser. Konsistensen på gel A och C är mer påverkade av gelningsgraden än total koncentration HA. För gel B kan ingen dominerande parameter utläsas. / The softness of a gel made of crosslinked HA (HA = hyaluronic acid) depends onthree factors. One is the amount of free hyaluronic acid in the gel. Another is thedensity of the crosslinked network, which is the molecular entanglements in the gel.The third is the total concentration of HA. In this project a rheometer is used to measure the rheological properties by runningthe following tests: time sweep, frequency sweep and amplitude sweep. From theobtained data, parameters related to viscous properties (G’’) and elastic properties(G’) of the gels were observed. 27 different compositions of gels with three differentconcentrations (35 mg HA/g, 25 mg HA/g, 15 mg HA/g), three different gel contents(100%, 90%, 80%) and three different densities of crosslinked network (A, B, C) wereanalyzed. To draw further conclusions an analysis of extrusion force was performedas well. The results from the frequency sweeps show that the loss tangent for a gel increasedas the total concentration of HA was reduced and that the loss tangent for a gelincreased as the gel content was decreased. This indicates that the gels become moreviscous when either the concentration of HA or the gel content was decreased. Anincrease in concentration of HA results in an increase of G' and an increase of gelcontent also results in an increase of G'. The results from the amplitude sweeps showthat xG' (xG' = storage modulus at the crossover point between G' and G'') increasesas either the concentration of HA or the gel content is increased. For xStrain (xStrain= deformation of the gel at the crossover point) and xStress (xStress = the stressapplied to the gel at the crossover point) no clear trend can be seen regarding the gelcontent. But an increase in concentration of HA results in an increase of both xStrainand xStress. The results from the analysis of extrusion force show that an increase intotal concentration HA increases the force.
313

Enclosing and Mounting an Electronic Component on Articulated Haulers : A proposition on how to protect, and where to place, an intelligent node on the environmentally harsh exterior of construction equipment with respect to multiple parameters

Sintorn, Johan January 2016 (has links)
As is the case with many other manufacturers of vehicles, Volvo Construction Equipment has a constantly increasing amount of electric and electronic equipment in their articulated haulers. These are of great use in modern machines, bringing functions, and safety that were not possible before, but they also bring more cables to handle. In the case of the articulated haulers a quite thick cable harness of about 15 meters in length reaches from the driver’s cabin in the front to the components in the far back end of the vehicle. This is not only a lot of long cables to handle both during assembly and service, but the nature of signals traveling in cables is that the voltage gets weaker with distance. This phenomenon has to be accounted for by measuring devices dependent on the voltage. It has been suggested that a device referred to as an intelligent node, or ICCS-module, which communicates digitally via CAN could be installed in the back of the articulated haulers. This module would be independent of the mentioned drop in voltage. The ICCS-module will be receiving a small bundle of cables being routed from the driver’s cabin. From it cables would go out to a majority of the components in its vicinity. The components connected to the node would not need to have any other cables. This thesis is focused on the mechanical aspects of installing this ICCS-module. Having electric and electronic equipment on construction vehicles is a challenge when it comes to protecting the device from the harsh environment that is the hauler’s exterior. It will have to withstand being immersed in water for long periods of time, greatly varying temperatures, vibrations and shocks as well as being hit by projectiles. The placement as well as the design of the enclosure should be chosen with respect to both the devices length of life and how well it fulfils its intended role and achieves the expected results. To produce an enclosure and find a placement aiming to satisfy these conditions, a traditional product development process were executed. The articulated haulers as well as relevant literature were researched. Concepts were generated and evaluated by both the author and by employees at Volvo Construction Equipment until a final concept for the enclosure and placement were found. The enclosure were then designed in detail specifying the material, manufacturing techniques, controlled for thermodynamic circumstances, modelled in Catia V5 and controlled for vibrations. It was concluded that the enclosure should be able protect the ICCS-module after some more development and that the placement and cable routing results in a much shorter total cable length.
314

Aufbau und Funktionsnachweis eines optischen Moduls mit optisch-analoger Pulsübertragung für den AMANDA-II- und ICECUBE-Detektor

Schmidt, Torsten 15 November 2002 (has links)
Für den AMANDA-Detektor wurde ein neuartiges Optisches Modul - das digitale Analoge Optische Modul (dAOM) - entwickelt. Es vereint sowohl lokale 'Intelligenz' zur Steuerung als auch aktive Elektronik zur optisch-analogen und elektrisch-analogen Pulsübertragung. Vorteile der optisch-analogen Übertragung sind die Immunität gegenüber einem Übersprechen zwischen den Signalkabeln, ein größerer linearer Signalbereich und eine gute Zeit- sowie Doppelpulsauflösung, wohingegen die elektrisch-analoge Übertragung das robuste elektrische Kabel als Verbindung mit der Datennahme nutzt. Deshalb dient sie als Ersatzübertragung, falls die optische Verbindung beschädigt wird. In der Saison 1999/2000 wurden 23 dAOMs im AMANDA-II-Detektor erfolgreich installiert. Das dAOM-Konzept wurde daraufhin weiterentwickelt. Der sogenannte dAOM++ war eine nahezu ideale Lösung für den zukünftigen ICECUBE-Detektor. / For the AMANDA detector a new type of Optical Module - the digital Analog Optical Module (dAOM) - has been developed. It incorporates some local 'intelligence' for slow control as well as active electronics for optical analog and electrical analog pulse transmission. Advantages of the optical analog transmission are the absence of crosstalk, a higher linear signal range and a good timing and double pulse resolution, whereas the electrical transmission uses the robust electrical cable as transmission line to the data aquisition. For that reason it is the fallback solution in case of a damaged optical transmission line. 23 dAOMs have been successfully installed in the AMANDA-II detector during the 1999/2000 season. After that the dAOM concept was further improved towards the dAOM++, which was a almost ideal solution for the ICECUBE detector.
315

Moduluppbyggnad av ramstyrda dumprar ur ett produktionsperspektiv – Volvo CE AB i Braås / Module construction of articulated haulers through a production perspective – Volvo CE AB in Braås

Skoog, Johanna, Nagy, Thomas January 2006 (has links)
Denna rapport i form av examensarbete för utbildningsprogrammet Managing Technology and Business Projects, är en del i Volvos framtida produktions-/ produktstrategier. Uppsatsens syfte är att ur ett produktionsperspektiv understödja Volvo Construction Equipment i Braås i strävan mot en ökad modulindelning av ramstyrda dumprar, som en del i utvecklingsarbetet för en effektivare produktion. Resultat har uppnåtts genom analys av intern och extern benchmarking jämfört med den teori som finns inom ämnesområdet modulindelning. Huvudresultatet visar att teorin och verkligheten skiljer sig genom att modulindelning ska anpassas individuellt utifrån varje företag och inte fungerar som en generellt applicerbar process. Slutsatsen visar att Volvo CE i Braås måste utveckla en egen handlingsplan och kravspecifikation utifrån egna definitioner som är skräddarsydda specifikt för företaget. I rapporten presenteras förslag till ovanstående handlingsplan för modulindelning på Volvo CE i Braås. / This diplomawork is the ending part of the education program Managing technology and Business Projects at Växjö University and was given as an assignment from Volvo Construction Equipment in Braås. The work is a part of Volvos future production- and product strategies and aims to support Volvo in their work towards a module classification of the articulated hauler line built in Braås. The result has been reached trough analysis of internal and external benchmarking compared to the theory regarding the subject. The main result shows that theory diverges from reality in the way that modularization must be adjusted individually for each company and that it doesn’t work as a general applicable process. The conclusion shows that Volvo CE in Braås must develop a unique plan of action from the in-house definitions that is tailored specifically for the company.
316

Moduluppbyggnad av ramstyrda dumprar ur ett produktionsperspektiv – Volvo CE AB i Braås / Module construction of articulated haulers through a production perspective – Volvo CE AB in Braås

Skoog, Johanna, Nagy, Thomas January 2006 (has links)
<p>Denna rapport i form av examensarbete för utbildningsprogrammet Managing Technology and Business Projects, är en del i Volvos framtida produktions-/ produktstrategier.</p><p>Uppsatsens syfte är att ur ett produktionsperspektiv understödja Volvo Construction Equipment i Braås i strävan mot en ökad modulindelning av ramstyrda dumprar, som en del i utvecklingsarbetet för en effektivare produktion. Resultat har uppnåtts genom analys av intern och extern benchmarking jämfört med den teori som finns inom ämnesområdet modulindelning. Huvudresultatet visar att teorin och verkligheten skiljer sig genom att modulindelning ska anpassas individuellt utifrån varje företag och inte fungerar som en generellt applicerbar process. Slutsatsen visar att Volvo CE i Braås måste utveckla en egen handlingsplan och kravspecifikation utifrån egna definitioner som är skräddarsydda specifikt för företaget.</p><p>I rapporten presenteras förslag till ovanstående handlingsplan för modulindelning på Volvo CE i Braås.</p> / <p>This diplomawork is the ending part of the education program Managing technology and Business Projects at Växjö University and was given as an assignment from Volvo Construction Equipment in Braås.</p><p>The work is a part of Volvos future production- and product strategies and aims to support Volvo in their work towards a module classification of the articulated hauler line built in Braås.</p><p>The result has been reached trough analysis of internal and external benchmarking compared to the theory regarding the subject. The main result shows that theory diverges from reality in the way that modularization must be adjusted individually for each company and that it doesn’t work as a general applicable process. The conclusion shows that Volvo CE in Braås must develop a unique plan of action from the in-house definitions that is tailored specifically for the company.</p>
317

On projective resolutions of simple modules over the Borel subalgebra S^+(n, r) of the Schur algebra S(n, r) for n ≤3 / Ueber projektive Aufloesungen von einfachen Modulen ueber die Borel Unteralgebra S^+(n,r) von der Schuralgebra S(n,r) fuer n ≤3

Yudin, Ivan 16 March 2007 (has links)
No description available.
318

Řízení jakosti u vybraných výrobků ve firmě Robert Bosch, spol. s .r.o. / The management of quality of selected products in company Robert Bosch, Ltd.

FENCL, Rostislav January 2010 (has links)
In summary of literature is definition of concept like quality, her history, and the management of quality and the cost of quality. The theses defines the concern of Bosch, production plant of Robert Bosch of České Budějovice, company history and secondly strategy and politics of quality system and the point and a results of quality system on assembly line DA {--} Daimler, on which are producing in-tank cars pumping devise. It is defined monitored product {--} the in-tank pumping device, the management of quality in the procedure of production and in all processes on workstations and than their specific quality control. Every single error in production process is analysed and results interpreted and a precaution is taken.
319

Modernisering av testutrustning / Modernization of Testing Equipment

Gustafsson, Thomas January 2012 (has links)
Rapporten beskriver arbetet med att modernisera en testutrustning för ett robotsystem. Den nya testutrustningen skulle moderniseras till att använda USB-gränssnitt istället för RS232-gränssnitt för kommunikation mellan dator och den övriga hårdvaran. Arbetet börjar med kravspecifikation och slutar med en fungerande produkt. I det innefattas en kortare förklaring av USB-gränssnittet och dess skillnader från RS232-gränssnittet, en utredning för att finna den bästa lösningen för att förverkliga USB-kommunikationen med utrustningen och konstruktion av elektronik för att styra signaler och spänningsmatningar till robotsystemet. / This report describes the work to modernize a test equipmentt for a missile system. The new test equipment would be upgraded to use a USB interfaces instead of RS232 interface for communication between the computer and the rest of the hardware. The work begins with the specification and ends with a working product. In that included a brief explanation of the USB interface and its differences from the RS232 interface, an investigation to find the best solution for implementing USB communication with the equipment and construction of electronics to control signals and power supplies to the missile system.
320

Modul evidence majetku provozovaný jako služba v ERP pro malé a střední firmy / The module of assets records operated as a service in ERP for small and medium enterprises.

Sýkora, Ondřej January 2011 (has links)
This diploma thesis deals with a comparison of available "as a service" solutions for enterprise asset records for small and medium businesses in the Czech market. The aim is to find solutions that would best suit the needs of companies to acquire a new system as a service module such as elimination of large initial investment into selected solution and extensive funding for its maintenance. The thesis introduces concepts such as ERP ASP, SaaS, Cloud computing, SLA and their characteristics in the theoretical part of the thesis, which is in the first two chapters. The practical part -- third and fourth chapter -- deals with the practical analysis of current business process property records, finding the gaps and the call for essential criteria for the selection of a new solution. It also search for available solutions in the Czech Republic and analyzes their characteristics at the base of pre-selected criteria and peer comparison. The fifth and last chapter deals with the calculation and evaluation of the suitability and subsequent recommendations for the selection of a particular solution. The thesis draws data from publicly available information provided by suppliers of "as a service" modules solutions for enterprise asset records management.

Page generated in 0.0564 seconds