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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.
131

Superposition in the leading edge region of a film cooled gas turbine vane

Anderson, Joshua Brian 04 April 2014 (has links)
The leading edge of a turbine vane is subject to some of the highest temperature loading within an engine, and an accurate understanding of leading edge film coolant behavior is essential to efficient engine design. Although there have been many investigations of the adiabatic effectiveness for showerhead film cooling within the leading edge region, there have been no previous studies in which individual rows of the showerhead were tested with the explicit intent of validating superposition models. For the current investigation, a series of adiabatic effectiveness experiments were performed with a five-row showerhead, wherein each row of holes was operated in isolation. This allowed evaluation of superposition on both the suction side of the vane, which was moderately convex, and the pressure side of the vane, which was mildly concave. Superposition was found to accurately predict performance on the suction side of the vane at lower momentum flux ratios, but not for higher momentum flux ratios. On the pressure side of the vane, the superposition predictions were consistently lower than measured values, with significant under-prediction of adiabatic effectiveness occurring at the higher mass flow rates. Possible reasons for the under-prediction of effectiveness by the superposition model are presented. / text
132

Energikartläggning av Kv. Freden, Gävle : Simulering av åtgärder och dess energibesparingspotential med modellerings- och simuleringsprogram IDA ICE

Englund, Marcus, Sahlström Moen, Simon January 2015 (has links)
Koldioxidnivåerna ökar i takt med en allt högre världslig energianvändning. Detta har lett till reglering och bestämmelser av utsläppsrätter samt energianvändning. För att stoppa den globala uppvärmningen och minska energianvändningen har EU enats om fyra gemensamma mål att uppnå till år 2020, även benämnda 20-20-20 målen. Lika så har Sverige satt upp egna miljömål att sträva efter till år 2020. De omfattar en ökning av andel förnyelsebar energi med minst 50 procent, effektivisera energianvändningen med minst 20 procent samt öka andelen förnyelsebar energi i transportsektorn med minst 10 procent.  Tack vare lagar gällande krav på skärpt energianvändning och utsläpp strävar företag mot användandet av energieffektivare teknik och ett mer energimedvetet beteende. Energikartläggning är ett viktigt samt effektivt verktyg vid kartläggning och illustrering av ett företags energianvändning för underlättande och tydliggörande av framtida åtgärd samt förbättring.  Examensarbetet syftar till att åskådliggöra Kv. Fredens energianvändning samt ta fram ekonomiskt genomförbara energibesparande åtgärder för att sänka energianvändningen både för denna och liknande byggnader. Till hjälp för utförande har sex frågeställningar använts vilka berör och syftar till att ta reda på energifördelningen i byggnaden, brister i drift och uppehållande av inomhusklimat samt ta fram kostnadseffektiva lösningar för val av åtgärd.För tillvägagång av arbetet har fem metoder valts för besvarande av frågeställningar. En litteraturstudie utfördes med hjälp av nyckelord som ”Energy saving”, ”Energy audit” samt ”Behaviour” i online-databaser för vetenskapliga artiklar. Därefter utfördes en empirisk analys av tillhandahållen data för byggnaden, vilket möjliggjorde modellering och simulering av byggnaden i programmet IDA ICE 4.6.1. För styrkande av antaganden samt undersökning av energimedvetet beteende utfördes termografering och en kvalitativ enkätundersökning.  Efter utförande av arbetet med hjälp av nämnda metoder, konstateras bristfällig ventilation. Vid simulerad installation av FTX i byggnaden uppnås en maximal energibesparing på dryga 17 procent, vilket motsvarar en slutlig energianvändning på 97 kWh/m2. Simulerade åtgärder, exklusive FTX, vilka visar sig vara mest lönsamma för byggnaden är tätning av dörrar och fönster för minskad infiltration. Dessa två simulerade åtgärder är de mest kostnadseffektiva simulerade lösningarna för Kv. Freden samt liknande byggnader.   Den simulerade energianvändningen för byggnaden representeras av 29 procent elanvändning samt 71 procent fjärrvärmeanvändning, vilka förhåller sig till en tillförlitlighet motsvarande 97,5 procent respektive 96 procent jämfört med energidata tillhandahållen av Gävle Energi. Simuleringsprogrammet IDA ICE visade sig vara ett effektivt hjälpmedel vid simulering av en byggnads energianvändning samt applicering av möjliga åtgärder. / Carbon dioxide levels are increasing as a consequence of larger energy use worldwide. This has led to regulations and rules of emission and energy consumption. In order to stop global warming and reduce energy consumption, EU has agreed on four common goals to achieve by the year 2020, also known as the 20-20-20 goals. Sweden has also come up with its own environmental goals to achieve by the year 2020. They include increasing the share of renewable energy by at least 50 percent, improve the use of energy by at least 20 percent and increase the share of renewable energy in the transportation sector by at least 10 percent.   Due to the laws and requirements related to stricter energy consumption and carbon emissions companies strive to use more energy efficient technology and more energyconscious behavior. Energy audit is an effective and an important tool in identifying and illustrating a company's energy usage for the clarification of future measures and improvement.  The thesis aims to illustrate Kv. Freden's use of energy and come up with both economically and energy saving measures to reduce its and other similar building's energy consumption. Six questions have been used to determine the energy distribution in the building and find defects in the management and maintenance of the indoor climate and develop cost-effective solutions for the choice of measures.   Five methods were chosen for approaching and answering the questions. A literature review was performed using keywords such as "Energy Saving", "Energy Audit" and "Behaviour" in online databases containing scientific articles. Thereafter an empirical analysis of the data supplied for the building was performed, which enabled modeling and simulation of the building in the program IDA ICE 4.6.1. A thermography and a qualitative survey regarding energy conscious behavior were performed as proof of assumptions.  The ventilation in this thesis is found inadequate after applied methods.  With simulated FTX-systems installed in the building, a maximum energy saving potential about 17 percent is achieved, which corresponds to a energy use of 97 kWh/m2. Excluding FTX, the simulated measures which prove to be the most profitable for the building is the sealing of doors and windows in order to reduce infiltration. These two measures are the most cost effective energy saving solutions regarding Kv. Freden and similar buildings.  The building's simulated energy use is represented by 29 percent electricity and 71 percent of district heating usage, which compared with the energy data provided by Gävle Energi relates to a reliability equivalent to 97.5 percent and 96 percent. The simulation program IDA ICE proved to be an efficient tool for the simulation of a building's energy use and application of possible measures.
133

Σύστημα ανάλυσης θερμικών δεδομένων που βασίζονται στη θερμοκρασία της επιφάνειας του μαστού για τον εντοπισμό παθολογικών καταστάσεων

Κεφάλα, Όλγα 24 November 2014 (has links)
Ο καρκίνος του μαστού αποτελεί μία από τις συχνότερα εμφανιζόμενες μορφές καρκίνου παγκοσμίως και είναι η πρώτη σε αριθμό κρουσμάτων στο γυναικείο πληθυσμό. Υπολογίζεται ότι στην Ελλάδα κάθε χρόνο προσβάλλονται από καρκίνο του μαστού 4500 γυναίκες και χάνουν τη ζωή τους 1500, ενώ υπολογίζεται ότι 1 στις 8 γυναίκες παγκοσμίως θα παρουσιάσει καρκίνο μαστού σε κάποια φάση της ζωής της. Είναι ενδιαφέρον ότι, στην Ευρώπη, το 60% των κρουσμάτων καρκίνου του μαστού διαγιγνώσκεται σε πρώιμο στάδιο – ποσοστό που στην Ελλάδα μόλις και μετά βίας εγγίζει το 5%. Τα στοιχεία αυτά καταδεικνύουν πόσο ελλιπής είναι η σχετική ενημέρωση μεταξύ των Ελληνίδων, γεγονός εξαιρετικά λυπηρό, αν λάβουμε υπόψη τις δυνατότητες πλήρους ίασης που παρέχει μία έγκαιρη διάγνωση. Τα ποσοστά θανάτου από καρκίνο του μαστού χαρακτηρίζονται από πτωτική τάση από τις αρχές του 1990, με τις μεγαλύτερες μειώσεις να εντοπίζονται στις γυναίκες κάτω των 50. Οι ερευνητές αποδίδουν την πτώση αυτή στην έγκαιρη διάγνωση μέσω μαστογραφιών καθώς και στις βελτιώσεις που έχουν επέλθει στις σχετικές θεραπευτικές αγωγές. Ο αριθμός των ατόμων που έχουν αντιμετωπίσει με επιτυχία τον καρκίνο του μαστού αυξάνεται συνεχώς - από τον Ιανουάριο του 2006, υπήρξαν περίπου 2,5 εκατομμύρια γυναίκες στις ΗΠΑ που, βάσει της έκθεσης, έχουν ξεπεράσει με επιτυχία την περιπέτεια του καρκίνου του μαστού. Το κλειδί για την επιτυχή καταπολέμηση του καρκίνου του μαστού είναι η πρώιμη ανίχνευση. Ο έγκαιρος εντοπισμός επιτυγχάνεται με διάφορες διαγνωστικές τεχνικές όπως η μαστογραφία, το σπινθηρογράφημα, το υπερηχογράφημα κ.α. Στη διπλωματική αυτή εργασία γίνεται προσπάθεια περιγραφής μια πειραματικής τεχνικής που βασίζεται στη θερμοκρασία της επιφάνειας του μαστού και που έχει ως σκοπό να λειτουργήσει συμπληρωματικά στις υπόλοιπες διαγνωστικές μεθόδους. / The breast cancer is one of the most common kinds of cancer worldwide and the first in incidence counts among women. It is estimated that 4500 women in Greece are diagnosed with breast cancer every year and 1500 die from breast cancer, while about 1 in 8 women worldwide will develop invasive breast cancer over the course of her lifetime. It is interesting that in Europe the 60% of the breast cancer incidence counts is diagnosed in an early stage, while in Greece this percentage barely reaches the 5%. These data reveal how deficient the decreased awareness among Greek women, which is really sad considering the chances for a full recovery in case of early detection. Breast cancer death rates began decreasing since 1990, with larger decreases in women under 50. These decreases are thought to be the result of treatment advances, earlier detection through screening, and increased awareness. The amount of people that have survived breast cancer is constantly increasing. Since January of 2006, more than 2,5 million women in the United States have been treated for breast cancer. The key for the successful prevention and treatment of breast cancer is the early detection. The early detection is achieved with various diagnostic screening techniques such as mammography, scintigraph, ultrasound etc. In this diploma thesis an experimental method which is based on breast surface temperature is being described and its purpose is to work supplementary with the rest of methods.
134

Using the Dual Control Model to investigate the relationship between mood, physiological and self-reported sexual arousal in men and women

Hodgson, Blair 02 August 2013 (has links)
Recent findings suggest that there is considerable inter-individual variability in how mood affects sexual arousal. The current research proposes that the Dual Control Model may be important to explaining this variation. Thirty-three participants (18 male and 15 female) aged 18 to 45, attended three laboratory sessions where they completed questionnaires assessing pre-existing mood and propensity for sexual excitation and inhibition, then watched a series of neutral and erotic films. Participants continuously indicated their subjective sexual arousal during each film, while genital temperature was measured using thermographic imaging. The results indicated that mood interacted with the elements of the Dual Control Model to significantly predict both genital and subjective sexual arousal. The interactions between mood and sexual excitation and inhibition tended to better predict genital arousal for female participants and subjective sexual arousal for male participants. The results suggest that Dual Control Model is an important factor in understanding how mood affects sexual arousal. / Canadian Institutes of Health Research, Canadian Male Sexual Health Council, Fonds Recherche Santé du Québec, Pfizer and the Ontario Ministry of Training, Colleges and Universities.
135

Thin film coatings for new generation infrared thermal picture synthesising devices

Rodriguez, Jose Virgilio Anguita January 2001 (has links)
No description available.
136

Termografijos taikymo veterinarijoje analizė / Analysis of thermography application in veterinary medicine

Genys, Alfonsas 05 March 2014 (has links)
Pastaruoju metu Europos Sąjungoje ir kitose pasaulio valstybėse daug dėmesio skiriama gyvūnų sveikatos užtikrinimui ir naujų technologijų diegimui, susijusių su ligų prevencija. Siekiama tobulinti ir vykdyti ligų prevencijos ir kontrolės programas, ieškanti naujų modernių tyrimų metodų gyvūnų sveikatos būklei tirti.Daugelis patologinių pakitimų atsiranda dėl temperatūros pokyčių. Infraraudonųjų spindulių termografija (IRT) yra neinvazinis metodas matuojantis spinduliuojamos šilumos skleidimą iš odos, atspindintis medžiagų apykaitą (Jones, Plassmann, 2002). Šio metodo pagalba galima aptikti organizmo funkcinius sutrikimus, lūžių, sąnarių ir raiščių traumas, patempimus, uždegimo procesus, karščiavimą.Šiandien termografiniai tyrimai veterinarijos kryptyje Lietuvoje nevykdomi, jie vis plačiau naudojam medicinojoe įvairiose srityse ir net onkologijoje. Darbo tikslas- išanalizuoti, susisteminti ir ištirti infraraudonosios spinduliuotės (IFR) taikymo galimybes veterinarijoje bei atlikti karvių galūnių termografinius tyrimus. Darbo uždaviniai: 1. Išanalizuoti ir susisteminti termografijos taikymo galimybes veterinarijoje. 2. Nustatyti FLIR sistemos. THERMA CAM P640 taikymą karvių bandoje kojų būklei vertinti kartu naudojant ir šlubavimo taškų vertinimo sistemą. 3. Atlikti karvių galūnių ortopedinį tyrimą. Darbo metodika: darbas atliktas 2012 kovo– birželio mėnesiais tirta Lietuvos juodmargių populiacijos aukšto pieningumo karvių banda (n=97).Karvių priekinių ir užpakalinių kojų... [toliau žr. visą tekstą] / Recently, the European Union and other countries of the world has paid much attention to animal health security and the introduction of new technologies related to the prevention of disease. The aim is to improve and promote programs of the prevention and control of disease by searching for new modern research methods to examine the animal health condition. Many pathological changes are caused by temperature changes. Infrared thermography (IRT) is a non-invasive method of measuring the intensity of heat dissemination from the skin, reflecting metabolism (Jones, Plassmann, 2002). This method helps to detect functional disorders of the body, fractures, joint and ligament injuries, sprains, inflammation processes, and fever. Currently, thermographic research is not carried out in the field of veterinary in Lithuania, although they are widely applied in various fields of medicine and even cancer treatment. The aim of the research- to analyse, systematize and investigate the possibility to apply infrared rays (IR) in the field of veterinary medicine as well as to perform the thermal analysis of cows limbs. The tasks of the research: 1. To analyse and systematize the possibility to apply thermography in the field of veterinary medicine. 2. To determine the possibility to apply FLIR system THERMA CAM P640 in the assessment of the cow leg condition in a herd also using the assessment system of limping points. 3. To perform the orthopedic examination of the cow limbs. The research was... [to full text]
137

Automatic Features Identification with Infrared Thermography in Fever Screening

Surabhi, Vijaykumar 12 January 2012 (has links)
The goal of this thesis is to develop an algorithm to process infrared images and achieve automatic identification of moving subjects with fever. The identification is based on two main features: the distinction between the geometry of a human face and other objects in the field of view of the camera, and the temperature of the radiating object. Infrared thermography is a remote sensing technique used to measure temperatures based on emitted infrared radiation. Applications include fever screening in major public places such as airports and hospitals. Current accepted practice of screening requires people to stay in a line and temperature measurements are carried out for one person at a time. However in the case of mass screening of moving people the accuracy of the measurements is still under investigation. An algorithm constituting of image processing to threshold objects based on the temperature, template matching and hypothesis testing is proposed to achieve automatic identification of fever subjects. The algorithm was first tested on training data to obtain a threshold value (used to discriminate between face and non face shapes) corresponding to a false detection rate of 5%, which in turn corresponds to 85% probability of detection using Neyman-Pearson criterion. By testing the algorithm on several simulated and experimental images (which reflect relevant scenarios characterizing crowded places) it is observed that it can be beneficially implemented to introduce automation in the process of detecting moving subjects with fever.
138

Real Time Image Processing For Medical Infrared Imaging

Kiziloz, Cemil 01 December 2005 (has links) (PDF)
This thesis focuses on Medical Infrared Imaging. It deals with the implementation of an infrared imaging system that can be used as a thermograph. A user interface program is also signed in order to control the imaging system. The system is implemented using Very High Speed Integrated Circuit Description Language (VHDL). Digitizing the data is implemented by Field Programmable Gate Array. Non-uniformities at the detector data are corrected by the two-point correction algorithm. To obtain absolute temperature readings, another system calibration process is also performed. Real-time histogram equalization algorithm and a realtime convolution operation are implemented using the VHDL. Tests of these implementations are performed by comparing the results with the numerical values. A user interface program is developed to allow the operator select any filter type and measure the temperature of any point in the object. Previous studies showed that an infrared system should detect a temperature difference of 500&deg / mK if it is to be used for biomedical applications. Using a black body system with a precise temperature control, it is shown that this specification is satisfied. Clinical evaluations for a few patients reveal that the implemented medical infrared system can be used for biomedical applications.
139

Aspekte zur klinischen Anwendung der Infrarot-Thermographie in der Zoo- und Wildtiermedizin

Hilsberg, Sabine 28 November 2004 (has links) (PDF)
Aspekte zur klinischen Anwendung der Infrarot-Thermographie in der Zoo- und Wildtiermedizin. Die Infrarot-Thermographie ist eine nichtinvasive Methode. Mit einer Infrarot-Kamera wird eine Messung der Körperoberflächen-Temperatur aus der Distanz durchgeführt und das Thermoprofil des Tieres als Thermogramm dargestellt. Es bedarf keines direkten Tierkontaktes und keiner Immobilisation. Viele Fallbeispiele belegen, dass die Infrarot-Thermographie eine erfolgversprechende neue Methode in der Zoo- und Wildtiermedizin ist. Schwerpunkte der Arbeit waren: - Erforschung artspezifischer Thermoregulation, besonders im Hinblick auf Tierhaltung und krankheitsauslösende Faktprem bei Zoo- und Wildtieren, - Reproduktionsforschung mittels Infrarot-Thermographie und - Entzündungsdiagnostik mittels Infrarot-Thermographie. Die meisten hier vorgestellten Ergebnisse sind Erstuntersuchungen weltweit. / Aspects of the clinical application of Infrared-Thermography in Zoo- and Wildlife Medicine Infrared-thermography is a non-invasive method. With an infrared-camera, the body surface temperature of an animal is measured from a distance and the thermoprofile of this animal is then displayed as a therogram. No direct animal contact or immobilization is necessary. Many case reports show that infrared-thermography is a promising new method in zoo and wildlife medicine. In this thesis threee topics are emphasized: - research in species-specific thermoregulation with regard to animal keeping and disease predisposing factors, - research in reproduction using infrared-thermography, and - inflammation diagnosis using infrared-thermography. Most of the presented results are from primary investigations worldwide.
140

Quantitative Line-Scan Thermographic Evaluation of Composite Structures

Kaltmann, Deena, s8907403@student.rmit.edu.au January 2009 (has links)
This MEng (Master of Engineering) research thesis evaluates the capabilities and limitations of line-scan thermography for the non-destructive evaluation of composite structures containing hidden defects. In simple terms, line-scan thermography is a state-of-the-art technique in which a focused line of thermal energy is transmitted into a material. Line-scan thermography has great potential for the rapid and low cost non-destructive inspection of composite structures for aircraft, automobiles and ships. In this project, theoretical research exploring the heat transfer physics was undertaken in conjunction with experimental studies to develop an optimum inspection regime for line-scan thermography. The capability of line-scan thermography to detect impact damage in carbon/epoxy laminates was experimentally investigated in Chapter 3. From the impact side, in all materials, line-scan thermography overestimated the size of the impact damage whereas flash thermography underestimated the size. There was a close relationship between the ultrasonic profile and the line-scan thermographic thermal response curve. New experimental data has been produced and analysed for the ability of line-scan thermography to determine the defect as well as the defect size. It was found that line-scan thermography was able to distinguish back drilled holes, but it was not possible to determine accurate defect sizing due to the depth of the holes from the inspected surface and the limitations associated with the line-scan thermographic apparatus itself. There was excellent correlation between the C-scan ultrasonics intensity curves and the line-scan thermographs as well as excellent correlation with the theoretical results. The relationship between line-scan thermography and foreign body objects were experimentally investigated for carbon/epoxy composites. A major limitation found with line-scan thermography is its limited depth penetration, which is highlighted in the foreign object study using 6 mm and 13 mm diameter Teflon® discs and 13 mm Teflon® strips embedded in carbon/epoxy laminates. Depth penetration allowed only 2 mm resolution for the 13 mm diameter discs and 1.5 mm resolution for the 6 mm discs in a composite panel. The results of the investigation of stainless steel shim objects in carbon/epoxy laminates reveal that line-scan thermography is capable of determining their presence and size close to the surface. There was also excellent correlation between the ultrasonic response curve and the line-scan thermographic intensity curve. The results of the investigation of thermoplastic film foreign body objects in carbon/epoxy laminates show that at present line-scan thermography does not have the capability to determin e such defects. Experimental results show that line-scan thermography is capable of detecting large voids, back drilled holes, some foreign body objects, and impact damage. However, the ability of line-scan thermography to measure the defect dimensions is dependent on the size and type of damage, the distance from the line source, the depth of the defect, and the type of composite material.

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