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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.
1

Visualization and Quantification of Karst and Fractures in Cretaceous Carbonates, Cassis, France

Pomar, Kenri 01 January 2010 (has links)
Fractures in carbonate strata are often associated with dissolution features such as karst cavities along the fracture plane. Integration of full resolution 3D GPR data and outcrop observation allows the visualization and quantification of fractures and karst cavites in three dimensions. Three 3D GPR cubes were acquired in the Solvay quarry, Provence region, SE France. The quarry exposes an intensly fractured and karstified shallow-water Barremian carbonates with matrix porosity less than 1.8%. The quarry walls provide the 2D information of the fractures (location, type, orientation, dip, length, aperture, spacing and stratigraphic position) and the karst (location, size, shape, stratigraphic position and relationship with fractures), that were documented using 1D scan line measurement. Several deformation features are observed in the quarry, dominated by meter-scale joints and tension gashes, and also minor faults, burial and tectonic-related stylolites. Three major fracture orientations (E-W, NW-SE and N-S) were found in the quarry with a non-uniform distribution influenced by structural position relative to major structural features (eg: large fractures (>10m) and faults). Interpretation of 3D GPR data reveals one major fracture orientation (NE-SW) that was not observed in the outcrop because it is oriented parallel with the quarry wall. Besides fractures, karst were also documented in outcrop as well as in 3D GPR data. Combination between 3D GPR and outcrop observation show that in the Solvay quarry karst occur along fracture plane and preferentially at fracture intersections. The karst are decimeter to meter-size karst which are below the resolution of 3D seismic reflection. Quantification of karst in the quarry show that karst size-frequency distribution follows power-law distribution, where small karst is more common and large karst is less common. The volume of karst in the quarry is up to 3.8% of the total rock volume. The power-law scaling relationship and the quantification of the sub-seismic karst volume will help predicting karst arrays in wide range of sizes in subsurface reservoirs, where visualization of karst is restricted to the resolution of 3D seismic data.
2

Development of multidimensional spectral data processing procedures for analysis of composition and mixing state of aerosol particles by Raman and FTIR spectroscopy / Élaboration de procédures de traitement des données spectrales multidimensionnelles pour l’analyse de la composition et de l'état de mélange d'aérosols atmosphériques par spectroscopie Raman et IRTF

Siepka, Damian 20 December 2017 (has links)
Les méthodologies de traitement de données multidimensionnelles peuvent considérablement améliorer la connaissance des échantillons. Les techniques spectroscopiques permettent l’analyse moléculaire avancée d’échantillons variés et complexes. La combinaison des techniques spectroscopiques aux méthodes de chimiométrie trouve des applications dans de nombreux domaines. Les particules atmosphériques affectent la qualité de l’air, la santé humaine, les écosystèmes et jouent un rôle important dans le processus de changement climatique. L’objectif de cette thèse a été de développer des outils de chimiométrie, simples d’utilisation, permettant de traiter un grand nombre de données spectrales provenant de l’analyse d’échantillons complexes par microspectrométrie Raman (RMS) et spectroscopie d’absorption IRTF. Dans un premier temps, nous avons développé une méthodologie combinant les méthodes de résolution de courbes et d’analyse multivariée afin de déterminer la composition chimique d’échantillons de particules analysées par RMS. Cette méthode appliquée à l’analyse de particules collectées dans les mines en Bolivie, a ouvert une nouvelle voie de description des échantillons. Dans un second temps, nous avons conçu un logiciel facilement accessible pour le traitement des données IRTF et Raman. Ce logiciel inclue plusieurs algorithmes de prétraitement ainsi que les méthodes d’analyse multivariées adaptées à la spectroscopie vibrationnelle. Il a été appliqué avec succès pour le traitement de données spectrales enregistrées pour divers échantillons (particules de mines de charbon, particules biogéniques, pigments organiques). / Sufficiently adjusted, multivariate data processing methods and procedures can significantly improve the process for obtaining knowledge of a sample composition. Spectroscopic techniques have capabilities for fast analysis of various samples and were developed for research and industrial purposes. It creates a great possibility for advanced molecular analysis of complex samples, such as atmospheric aerosols. Airborne particles affect air quality, human health, ecosystem condition and play an important role in the Earth’s climate system. The purpose of this thesis is twofold. On an analytical level, the functional algorithm for evaluation of quantitative composition of atmospheric particles from measurements of individual particles by Raman microspectrocopy (RMS) was established. On a constructive level, the readily accessible analytical system for Raman and FTIR data processing was developed. A potential of a single particle analysis by RMS has been exploited by an application of the designed analytical algorithm based on a combination between a multicurve resolution and a multivariate data treatment for an efficient description of chemical mixing of aerosol particles. The algorithm was applied to the particles collected in a copper mine in Bolivia and provides a new way of a sample description. The new user-friendly software, which includes pre-treatment algorithms and several easy-to access, common multivariate data treatments, is equipped with a graphical interface. The created software was applied to some challenging aspects of a pattern recognition in the scope of Raman and FTIR spectroscopy for coal mine particles, biogenic particles and organic pigments.
3

Analysis of Knee Joint Vibration Signal Acquired from In-line Skating Hockey Players

Shyu, Wei-horng 23 August 2006 (has links)
The knee joint is the most commonly injured joint in the body. Clinical methods used at present for the diagnosis of cartilage pathology in the knee are invasive in nature. Analysis of vibration signals emitted by the knee joint has the potential for the development of a non-invasive procedure for the diagnosis of knee pathology. By Short Time Fourier Transform (STFT) and calculating root mean square (RMS) value, via One Way ANOVA at last, to demonstrate whether the two analysis methods are valid in this work. The method was tested on 14 male volunteers from NSYSU (7 players of in-line skating and 7 normal schoolmates). By analyzing the signals extracted from the players, finding difference of them, and distinguishing whether they are healthy. In conclusion, if the knee joint ligament is unusual, the frequency of signal is higher than 50 Hz; if not, the frequency is lower than 10 Hz. On the other hand, the RMS value of signal has no distinct region among the testers, so could not be used to analyze the signals. The results should be able to take as the reference for the diagnosis of knee joint non-invasively in clinical medicine.
4

Univerzální mobilní komunikační platforma pracující s technologií bluetooth / Universal mobile communication platform using the bluetooth technology

Sopko, Richard January 2009 (has links)
This master’s thesis is focused on field of communication technologies in mobile devices in personal WPAN type wireless networks. Work consists of three basic parts. First part provides overview of personal WPAN wireless networks and is specialized on Bluetooth technologies and its opportunities of communication between mobile devices. Second part deals with an opportunity of using programming language Java 2 Micro Edition in work with Bluetooth technology. Key point of this work is third part which includes scheme of conception of a communication platform and creating of application designed for mobile phones. Created application enables communication by means of changing files and written conversation of two or more people in real time by Bluetooth connection.
5

Grouping and selecting products: the design key of reconfigurable manufacturing systems (RMSs)

Abdi, M. Reza, Labib, A.W. 31 July 2009 (has links)
No / A Reconfigurable Manufacturing System (RMS) is a new paradigm that focuses on manufacturing a high variety of products at the same system. Having specified a design strategy for an RMS as the first design step at the tactical level, products must be grouped to identify and allocate corresponding manufacturing facilities. An interface between market and manufacturing called reconfiguration link is presented to specify and arrange products for manufacturing. The reconfiguration link incorporates the tasks of determining the products in the production range, grouping them into families and selecting the appropriate family at each configuration stage. The proposed approach of (re)configuring products before manufacturing facilitates assigning product families to the required manufacturing facilities in terms of (re)configuring manufacturing systems. This paper contributes an overall approach of grouping products into families based on operational similarities, when machines are still not identified. Since the problem of product family selection consists of quantitative and qualitative objectives, the Analytical Hierarchical Process (AHP) is then used while considering both market and manufacturing requirements. The AHP model is verified in an industrial case study through using Expert Choice software. The solutions take advantage of monitoring sensitivity analysis while changing the priorities of manufacturing and/or market criteria. The concept of the proposed model is generic in structure and applicable to many firms. However, the model must be adapted according to the specific nature of the company under study. For instance, product family choices may differ from one company to another because of the available technology and the volume and type of existing products in the production range.
6

Prozessmodellierung von Reaktiv-Multischicht-Systemen (RMS)

Rühl, Maximilian 23 May 2016 (has links) (PDF)
The focus of this work is the theoretical and experimentell descreption of so-called Reactive Multilayer Systems (RMS). The RMS consist of at least two mostly metallic materials, which can exothermic response with each other. Using magnetron sputter deposition (MSD) several hundred to thousands alternating layers are produced. The periodic thickness varies between 10-150 nm and the total thickness between 10-100 µ m . The exotermic reaction is effected by an activation energy, e.g. with an electric spark. In this case a phase transition of the RMS materials, which are in a metastable equilibrium, will take place. This released energy in the shape of heat, which actvates the reaction in the neighboring areas. It forms a self-sustaining thermal wave through the RMS foil. In this case the amount of energy is present, that a solder on the RMS or the joining samples or even the material itself can be melted. Therefore the RMS can be used as a heat source for joining two components. The major advantage of this technology is the very low heat input in the bonding components, due to the milliseconds of the reaction. Thus the components are heated only superfical and there is no structural damage. Thus a very low-stress joining is possible. Furthermore is guaranteed, because of the metallic materials, a very high electrical and thermal conductivity. For the theoretical characterization of the physical and chemical processes within the RMS FEM-Simulations of the absolut temperature and the propagation velocity are preformed. In order to calculate the tmeperature ditribution in the components a new method will presented. It is thus possible to calculate the temperature penetration of the components to determine potential thermal barrier layer-thickness and the meltig time. Thus parameters for the specific joint problem such as period thickness, etc. of the RMS are derived. Modelling the heat transport after joining with RMS it is possible to derive a corralation between the thermal conductivity and shear strength. To quantify the theoretical results and to require certain parameters for the calculations experiments were preformed. The RMS will be investigated experimentally in terms of their enthalpy H , propagation velocity v , nascent temperature, melting time t schmelz , interdiffusion zone w , phase transition and its use as inovative heat source for joining components. The experimental results are compared with the theortical and complet this work.
7

Evaluation of performance of a smartphone application for measuring bike paths’ condition

Erlandsson, Jonas January 2013 (has links)
There are several methods to measure surface evenness for car roads, but almost none for bike paths. Accordingly, VTI (the Swedish National Road and Transport Research Institute) have created a smartphone application which uses the accelerometers in the phone to measure the vibration from the road. This report’s aim is to analyze the data collected using this application, investigate if the data is repeatable, to find factors that are important for evenness and perform classification of bike paths as even or wiggly. Two main methods were used, Gaussian process and wavelets. Gaussian process was used to classify bike paths and wavelets to investigate the repeatability and see how many trips are needed to get a consistent result. The results show that the two different smartphones gave quite different results; one smartphone indicated almost twice as high RMS values (measure of vibration) than the other. The GPS positions of smartphones were quite good, except under a tunnel and close to high buildings. Some short section of the road gave very high or very low RMS values, but the general standard of all investigated bike paths were too even to detect any significant differences between the paths. The results show that there’s some unexplained variance in the turns, but the effect of the turns hasn’t been tested. The wavelets analysis show that around 15 trips were needed to get a consistent result. The report contains a description of a designed experiment that will continue this project. This new data will be collected in a more carefully to make a better separation between good and bad cycle routes by the RMS value. / <p>Uppdragsgivare: VTI (Anna Niska och Leif Sjögren)</p>
8

Improved Heuristics for Partitioned Multiprocessor Scheduling Based on Rate-Monotonic Small-Tasks

Müller, Dirk, Werner, Matthias 01 November 2012 (has links) (PDF)
Partitioned preemptive EDF scheduling is very similar to bin packing, but there is a subtle difference. Estimating the probability of schedulability under a given total utilization has been studied empirically before. Here, we show an approach for closed-form formulae for the problem, starting with n = 3 tasks on m = 2 processors.
9

Kvalitativ jämförelse mellan UAS och GNSS för inmätning till baskarta / Qualitative comparison between UAS and GNSS regarding detail surveying for base maps

Forsberg, Axel, Werner Koning, Sebastian January 2022 (has links)
This study aims to compare advantages and disadvantages between detail surveying done with a drone (UAS) and GNSS equipment. Thus, in order to examine if detail surveying with UAS can be applicable for creating base maps in a more time efficient way. Aspects such as accuracy, environment, surroundings and ethics are shown consideration for. This was carried out by comparing data sampled from UAS flying and detailed surveying with GNSS. The flight altitude was 65 meters and the aerial photos were processed in Agisoft Metashape and ArcMap. GNSS was used to measure objects with high frequency, roughly 16 points per second and was later processed in GEO and ArcMap. Additional surveying was done with a total station in areas where the accuracy didn’t meet the requirements set by HMK. Establishment of free station was used when measuring with total station and the objects were then surveyed with a prism and direct measuring. Results that are relevant to this study are mainly RMS (Root Mean Square) and standard uncertainty. The results show that the time required for detailed surveying with UAS is 6 hours and 45 minutes, whilst for GNSS the time required is 8 hours and 30 minutes. Considering the RMS value and the standard uncertainty, the differences are marginally different. RMS value for UAS is 0.088 meters and standard uncertainty is 0.062 meters whilst for GNSS the RMS value is 0.084 meters and standard uncertainty is 0.058 meters. All measurements and results are within the 2nd standard level which are the requirements for a base map within an urban area. The results can be seen as reliable as the requirements set by HMK when practicing detailed surveying with UAS, GNSS and total station was followed. The time efficiency achieved when doing detailed surveying with UAS can make up for the increase in standard uncertainty as long as the results are within the recommendations set by HMK. Further studies could be applied to see how similar surveying results could look in areas with different environments and different sizes.
10

Development of a MR Hydraulic Bushing for Automotive Applications

Schubert, Brad January 2005 (has links)
The purpose of this work is to design a semi-active magnetorheological (MR) hydraulic bushing. The semi-active bushing is intended to be used to isolate a cylinder deactivating engine. Cylinder deactivation causes high transient torsional loading in addition to changing the magnitude and mode of engine vibrations requiring an adaptive or controllable isolator. <br /><br /> Practical and simple semi-active control strategies are inspired by investigating the optimization of linear and slightly cubic nonlinear single degree of freedom isolators. Experimental verification of the optimization technique, which minimizes the root mean square (RMS) of engine acceleration frequency response and RMS of the force transmitted frequency response, shows that this method can be implemented on real linear systems to isolate the engine from harmonic inputs. This optimization technique is also applied to tune selected model parameters of existing two degree of freedom hydraulic bushings. <br /><br /> This thesis also details the development of a MR hydraulic bushing. The MR bushing design retrofits an existing bushing with a pressure driven flow mode valve on the inertia track. A new efficient valve design is selected and developed for the application. The MR hydraulic bushing is designed, mathematically modeled, and numerically simulated. The simulation results show that the MR bushing tends to increase the low frequency dynamic stiffness magnitude while simultaneously decreasing the phase. The next stage of the project is fabrication and testing of the semi-active bushing. The performance of the manufactured MR bushing is tested on a base excitation apparatus. Varying the current input to the MR valve was found to have a small effect on the response of the suspended mass. The results are in agreement with the effects demonstrated by the dynamic stiffness numerical simulation.

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