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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.
31

Energibesparande åtgärder i livsmedelsbutiker / Energy saving measures in grocery stores

Karlsson, Mattias, Malmström, Marcus January 2013 (has links)
Underlaget till rapporten är att KF fastigheter arbetar aktivt med att minska energiförbrukningen i sina livsmedelsbutiker. För att underlätta beslutstagande och utvärdera olika nyinvesteringar har vi utformat en lathund för energibesparande åtgärder. Lathunden levereras som Excelfiler med förprogrammerade formler. Rapporten inriktar sig på kyl- och frysdiskar samt belysning eftersom dessa står för merparten (76 %) av den totala elförbrukningen i en livsmedelsbutik. Nyckelord: Energibesparing, Livsmedelsbutik, belysning, ljuskällor, Kyldisk, frysdisk, kylsystem, köldmedier, LCC, pay off, KF-fastigheter, kylsystem, köldmedier, lathund, beräkningsmall.
32

Development and Evaluation of an Active Radio Frequency Seeker Model for a Missile with Data-Link Capability / Utveckling och utvärdering av en radarbaserad robotmålsökarmodell med datalänkfunktion

Hendeby, Gustaf January 2002 (has links)
<p>To develop and maintain a modern combat aircraft it is important to have simple, yet accurate, threat models to support early stages of functional development. Therefore this thesis develops and evaluates a model of an active radio frequency (RF) seeker for a missile with data-link capability. The highly parametrized MATLAB-model consists of a pulse level radar model, a tracker using either interacting multiple models (IMM) or particle filters, and a guidance law. </p><p>Monte Carlo simulations with the missile model indicate that, under the given conditions, the missile performs well (hit rate>99%) with both filter types, and the model is relatively insensitive to lost data-link transmissions. It is therefore under normal conditions not worthwhile to use the more computer intense particle filter today, however when the data-link degrades the particle filter performs considerably better than the IMM filter. Analysis also indicate that the measurements generated by the radar model are neither independent, white nor Gaussian. This contradicts the assumptions made in this, and many other radar applications. However, the performance of the model suggests that the assumptions are acceptable approximations of actual conditions, but further studies within this are recommended to verify this.</p>
33

Forum shopping and the private enforcement of EU competition law : is forum shopping a dead letter?

Telfer, Robert Thomas Currie January 2017 (has links)
This thesis examines the relationship between the private enforcement of EU competition law and forum shopping with a particular focus on cross-border collective end-consumer redress. There is no coherent framework across the EU for these types of cases. This lack of uniformity has the potential to create recourse to different national courts. Lawyers may engage in forum shopping when filing lawsuits on behalf of the victims of mass torts. Such practices can provide Member States with incentives to amend their laws to attract collective proceedings and create competition between national judicial systems. However, forum shopping is not the only concern. There appears to be a paucity of cross-border collective claims. This is coupled with an apparent lack of motivation for end-consumers to seek a remedy, particularly if the only choice is to litigate outside their own legal regime. Addressing this situation is vital given that end-consumers regularly suffer harm in the form of higher prices, lower output, reduced quality and limited innovation as a result of antitrust infringements but they are rarely compensated due to legal and practical obstacles. To each end-consumer the harm may indeed be de minimis. However, the aggregate harm can amount to a considerable sum. In the absence of effective redress procedures, infringing undertakings retain the spoils of their unlawful conduct. Against this background, this thesis examines the extent to which the conflicts-of-laws rules encourage forum shopping and considers the appropriate forum and the appropriate procedural measures that need to be adopted in order to facilitate effective and equal access to justice for end-consumer victims of EU competition law violations.
34

Metodutveckling för bestämning av vattenhalten i en frystorkad proteinprodukt / Method development for determination of the water contentin a freeze-dried protein product

Said, Rana January 2018 (has links)
Vattenhalten i ett frystorkat proteinläkemedel bestämdes med KF och LOD som är två primära och traditionella metoder som används för bestämning av vattenhalten i produkter inom flera industrier. Istället för KF och LOD, som är tidskrävande och destruktiva, kan den sekundära, snabba och icke-destruktiva metoden NIR användas. För att kunna implementera NIR måste en kalibrering gentemot en primär metod ske. Syftet med detta projekt var att med en kvantitativ analys finna ett samband mellan NIR och KF samt mellan NIR och LOD för den frystorkade produkten. Det initiala steget var att upprätta en kalibreringsuppsättning och samla in spektrum med NIR. Därefter gjordes försök att bestämma vattenhalten med KF och LOD för den frystorkade proteinprodukten med inledande tester som verifierades genom att spetsa prover med vatten. LOD utfördes i en exsickator och KF-analyserna utfördes kolometriskt på två olika sätt, med och utan extraktion av proverna med metanol. Det slutgiltiga steget var att korrelera insamlat spektrum från NIR med bestämda referensvärden genom att skapa en kalibreringsmodell. Data från insamlat spektrum förbehandlades med multiple scatter correction (MSC), andra derivatan och Savitzy Golay, innan en kalibreringsmodell skapades med partial least square (PLS). Resultatet från LOD-analyserna med exsickator tydde på att tillvägagångssättet som användes inte var lämpligt för produkten och en kalibreringsmodell upprättades inte. Vattenhalten bestämdes med KF med extraktion av åtta prover till 0,144 – 0,558 % [w/w], och med KF utan extraktion till 2,34– 2,972 % [w/w] för åtta prover. Det förväntade värdet var 0,62-1,61 % [w/w]. En kalibreringsmodell upprättades för KF med och utan extraktion samt för det förväntade referensintervallet. Detta resulterade i en korrelationsfaktor på 0,9496 för KF med extraktion, 0,97418 för KF utan extraktion och 0,9932 för de förväntade värdena. Metoderna KF med och utan extraktion var inte lämpliga för produkten i detta projekt, utan fler försök behöver utföras med större kalibreringsuppsättningar för att kunna dra en slutgiltig slutsats. / The water content of a lyophilized protein drug is determined using KF and LOD which are two primary and traditional methods used by several industries for determination of water content in products. Instead of KF and LOD, which are time consuming and destructive, the secondary, fast and non-destructive method near infrared spectroscopy (NIR), can be used. To implement NIR, a calibration towards a primary method must be performed. The purpose of this study was to find a relation between NIR and KF and between NIR and LOD for the lyophilized product with a quantitative analysis. The initial step was to establish a calibration set and collect a spectrum with NIR. Attempts to determine the water content of KF and LOD for the lyophilized protein product were made with initial tests which later were verified by spiking samples with water. LOD was performed in a desiccator and the KF analyses were performed calorimetrically in two different ways: with and without extraction of the samples with methanol. The last step was to correlate the collected spectrum from NIR with determined reference values by creating a calibration model with partial least square (PLS). Prior to model development, data from collected spectrum was pre-treated with multiple scatter correction (MSC), second derivative and Savitzy-Golay filter. The result of the LOD analyses with a desiccator indicated that the method used was not suitable for the product and a calibration model was not established. The water content was determined by KF with extraction of eight samples to 0.144 - 0.558 % [w/w], and with KF without extraction of eight samples to 2.34-2.972 [w/w]. The expected value was 0.62-1.61 % [w/w]. A calibration model was established for KF with extraction of the samples, KF without extraction of the samples and for the expected reference interval. The developed calibration models resulted in a correlation factor of 0.9496 for KF with extraction, 0.97418 for KF without extraction and 0.9932 for the expected values. KF with and without extraction of the samples was not suitable for the product in this project. More experiments are needed with bigger calibration sets to be able to make a conclusion.
35

Stabilization, Sensor Fusion and Path Following for Autonomous Reversing of a Full-Scale Truck and Trailer System

Nyberg, Patrik January 2016 (has links)
This thesis investigates and implements the sensor fusion necessary to autonomously reverse a full size truck and trailer system. This is done using a LiDAR mounted on the rear of the truck along with a RTK-GPS. It is shown that the relative angles between truck-dolly and dolly-trailer can be estimated, along with global position and global heading of the trailer. This is then implemented in one of Scania's test vehicles, giving it the ability to continuously estimate these states. A controller is then implemented, showing that the full scale system can be stabilised in reverse motion. The controller is tested both on a static reference path and a reference path received from a motion planner. In these tests, the controller is able to stabilise the system well, allowing the truck to do complex manoeuvres backwards. A small lateral tracking error is present, which needs to be further investigated.
36

Light Flicker Evaluation Of Electric Arc Furnaces Based On Novel Signal Processing Algorithms

Kose, Neslihan 01 September 2009 (has links) (PDF)
In this research work, two new flickermeters are proposed to estimate the light flicker caused by electric arc furnaces (EAFs) where the system frequency deviates significantly. In these methods, analytical expressions of the instantaneous light flicker sensation are obtained beginning from a voltage waveform and these expressions are used to obtain a flicker estimation method based on the IEC (International Electrotechnical Commission) flickermeter. First method is a spectral decomposition based approach using DFT to estimate the light flicker. The leakage effect of the DFT algorithm due to fundamental frequency variation is reduced by employing spectral amplitude correction procedure around the fundamental frequency. Second method is a Kalman filter based approach, in which the frequency domain components of the voltage waveform are obtained by Kalman filtering. Then these components are used to obtain the light flicker. Since the frequency decomposition is obtained by Kalman filtering, no leakage effect of the DFT is involved in case of frequency deviations which is an important advantage. Both methods are tested on both simulated data and field data obtained from three different EAF plants where the flicker level and frequency variation is considerably high. The comparison with the digital realization of the IEC flickermeter shows that the methods are successful in estimating light flicker with low computational complexity. The methods are especially useful for conditions such as disturbances and subsequent system transients where the system frequency deviates significantly, since the methods avoid the need for online sampling rate adjustment to prevent the DFT leakage effect.
37

Sensor fusion and fault diagnosticsin non-linear dynamical systems.

Nilsson, Albin January 2020 (has links)
Sensors are highly essential components in most modern control systems and are used in increasingly complex ways to improve system precision and reliability. Since they are generally susceptible to faults it is common to perform on-line fault diagnostics on sensor data to verify nominal behavior. This is especially important for safety critical systems where it can be imperative to identify, and react to, a fault before it increases in severity. An example of such a safety critical system is the propulsion control of a vehicle. In this thesis, three different model-based methods for Fault Detection and Isolation (FDI) are developed and tested with the aim of detecting and isolating sensor faults in the powertrain of an electric, center articulated, four-wheel-drive vehicle. First, kinematic models are derived that combine sensor data from all sensors related to propulsion. Second, the kinematic models are implemented in system observers to produce fault sensitive zero-mean residuals. Finally, fault isolation algorithms are derived, which detect and indicate different types of faults via evaluation of the observer residuals. The results show that all FDI methods can detect and isolate stochastic faults with high certainty, but that offset-type faults are hard to distinguish from modeling errors and are therefore easily attenuated by the system observers. Faults in accelerometer sensors need extra measures to be detectable, owing to the environment where the vehicle is typically operated. A nonlinear system model shows good conformity to the vehicle system, lending confidence to its further use as a driver for propulsion control.
38

Estimation optimisée de l'utilisation de l'énergie sur un véhicule électrique

Andriaminahy, Nofinidy Ho Fanilo January 2021 (has links) (PDF)
No description available.
39

Formation Control of UAVs for Positioning and Tracking of a Moving Target

Carsk, Robert, Jeremic, Alexander January 2023 (has links)
The potential of Unmanned Aerial Vehicles (UAVs) for surveillance and military applications is significant — with continued technical advances in the field. The number of incidents where UAVs have intruded into unauthorized areas has increased in recent years and armed drones are commonly used in modern warfare. It is therefore of great interest to investigate methods for UAVs to locate and track intruder drones to prevent and counter surveillance of unauthorized areas and attacks from intruder UAVs. This master’s thesis studied how two autonomous seeker UAVs can be used cooperatively to track and pursue a target UAV. To locate the target UAV, simulated measurements from received Radio Frequency (RF) signals were used by extracting bearing and Received Signal Strength (RSS) data. To track the target and predict its future position, the study employed an Extended Kalman Filter (EKF) on each seeker UAV, which acted together as a Mobile Wireless Sensor Network (MWSN). The thesis explored two formation control methods to keep the seeker UAVs in formation while pursuing the target drone. The formation methods used the predicted position of the target to produce reference positions and/or reference distances for a controller to follow. A Distributed Model Predictive Controller (DMPC) was implemented on the seeker UAVs to pursue the target while maintaining formation and avoiding collisions. The EKF, MPC, and formation methods were first evaluated individually in simulation to assess their performance and for parameter tuning. The respective modules were then combined into the complete system and tuned to achieve improved pursuit and formation in simulation. The results showed that, with the chosen parameters and with a high level of measurement noise, the seeker UAVs were able to pursue the target with a combined average distance error of less than 2 m when the target drone flew in a square pattern with a velocity of 2 m/s. The quality of the pursuit was highly affected by the increase in velocity of the target and the initial positions of the seekers, where a high velocity and a large initial deviation from the reference positions/distances resulted in poorer quality.
40

Wǝ́xa Sxwuqwálustn : pulling together identity, community, and cohesion in the Cowlitz Indian tribe

Wheeler, Leah January 2017 (has links)
In the last 30 years many changes have taken place within the Cowlitz Indian Tribe. These changes involve the tribe’s sovereignty and have greatly impacted the emic identity of the tribe. Previous identity research with the Cowlitz predates these changes and no longer accurately describe the Cowlitz. The question for this research was how have these changes affected the emic identity of the Cowlitz today as seen in their community and interactions? And how does their identity now compare with their identity in the times of pre-contact and initial contact with whites? This research uses Manuel DeLanda’s assemblage theory to assess and compare the emic identity of the contemporary and historical tribe in terms of sovereignty, identity, and cultural rejuvenation. When the structure, relationships, activities, and purposes of the tribe and groups within the contemporary tribe were analyzed, there was a striking resemblance to the community system described in early settler journals and histories of the Cowlitz. The research was cross-sectional, including ethnographic study, interviews of tribal members, document analysis, and historical analysis. In an attempt to allow the Cowlitz people to speak for themselves rather than project ideas onto the tribe, each section of the research first allows tribal members to voice their opinions and then relies on Cowlitz voices to confirm the analysis. The final dissertation was then submitted to the tribe for comment.

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