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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.
251

Horizontal steering control in docking the ARIES AUV /

Tan, Wee Kiat. January 2003 (has links) (PDF)
Thesis (M.S. in Mechanical Engineering)--Naval Postgraduate School, December 2003. / Thesis advisor(s): Fotis Papoulias, Anthony J. Healey. Includes bibliographical references (p. 83). Also available online.
252

Factors Effecting Small and Medium Enterprises, Selection of Market Entry Mode / Factors Effecting Small and Medium Enterprises, Selection of Market Entry Mode

Malik, Naveed Hussain, chaudhary, Masood Hussain January 2010 (has links)
Development in infrastructure limits the communication gap, speedy travel and low cost tariff barriers as well other drivers of globalization have made overseas markets easier to get small firms and gave more opportunities to SME´s internationalize. The market entry mode choice or selections have strong effect the success or failure of the company. For instance an insufficient or wrong entry mode selection can decrease opportunities and limit important choice for the firm and could lead to high financial loss as well as lose control on overseas market. The purpose of research study is to provide a deep and better understanding of the factors those effecting SME´s selection of market entry mode. Research question how can the influence of internal and external factors on the selection of market entry mode. A frame of reference led to the building of summary which in turn became the basis for data collection. Two qualitative case studies for Pakistani SME´s namely socks knitter Pakistan and RK International were undertaken. The main findings shows the clear link between the theories claim to be internal and external factors influencing market entry mode choice between SME´s. / C/O Kamran Anjum Norrekaer 14. 7 Tv 2610 Rodovre Denmark
253

Recreational values of forests. : A case study.

Andersson, Kaj January 2015 (has links)
As swedes are keen on outdoor recreation and like to spend on travels and gear for forest recreation we want to show if there is a willingness to pay for forest recreation close to home. Starting in hedonic regression we create a model using publicly available data to show how consumer preferences effect house prices. Results show that distance to forest have a small but significant impact on house prices. To conclude we state that a logarithmic model using open source data can be useful in city planning and that there is a positive effect of nearby forests on house prices.
254

Av barn och dårar får man höra sanningen : konsumentengagemang på Facebook

Persson, Nina, Sörensson, Jenny January 2015 (has links)
Facebook, Interaktion, Kommunikation, Konsumentengagemang, Mode, Sociala nätverkSammanfattning på svenska: Medias utveckling har gått fort och det är inte bara konsumenter som använder sig av medier numera, även företag går att hitta i olika sociala medier. Facebook är ett utav världens snabbast växande sociala nätverk och finns tillgängligt över i stort sett hela världen, och en plats där konsument och företag kan mötas. Företag använder Facebook som en distributionskanal för marknadskommunikation och därmed behöver de förstå hur integrering av internet i traditionell marknadsföring kan göras. Samt hur de kan nyttja att direktkontakten med de konsumenter som besöker deras sida och få dem engagerade. Tidigare forskning pekar dock på att modebranschen finns andra utmaningar och möjligheter för att kommunicera med sina kunder. Uppsatsens syfte är därför att beskriva och skapa förståelse hur klädföretag i modebranschen kan använda sig av olika inlägg på Facebook för att skapa konsumentengagemang. Frågeställningen blir därmed: Hur påverkar olika typer av företagsinlägg på Facebook konsumenters engagemang? Uppsatsen har använt sig av kvantitativ innehållsanalys för att samla in data från Facebook och med hjälp av Honeycomb-modellen skapa relevanta resultat som kan svara på syftet. Uppsatsens resultat visar att modeföretag använder sig av Facebook som tidigare teorier föreslår. Men det finns skillnader i vilken typ av inlägg som skapar engagemang hos modebranschens konsumenter.
255

Υλοποίηση κρυπτο-επεξεργαστικής πλατφόρμας για κρυπτογράφηση μηνυμάτων στο πρότυπο Galois / Counter Mode (GCM)

Δακουρού, Στεφανία 19 October 2009 (has links)
Η παρούσα διπλωματική προτείνει μια hardware υλοποίηση για κρυπτογράφηση μηνυμάτων βασισμένη στο πρότυπο ασφαλείας Galois/Counter Mode (GCM). O αλγόριθμος κρυπτογράφησης Galois/Counter Mode (GCM) εκδόθηκε από τον οργανισμό National Institute of Standards and Technology (NIST) τον Νοέμβριο του 2007. Σε συνεργασία με τον μηχανισμό πιστοποίησης μηνυμάτων, υλοποιείται το συνολικό πρότυπο GCM για online λειτουργία. Στο Κεφάλαιο 1, αρχικά γίνεται μια σύντομη ιστορική αναδρομή στον τομέα της κρυπτογραφίας. Στην συνέχεια παρουσιάζονται οι λόγοι που οδήγησαν στην δημιουργία αυτού του προτύπου ασφαλείας. Ακολουθεί μια σύντομη εισαγωγή στον GCM και στους τρόπους με τους οποίος αυτός δουλεύει. Στο τέλος του κεφαλαίου αναφέρονται οι πρακτικές εφαρμογές που έχει η χρήση του G. Στο Κεφάλαιο 2, αρχικά αναφέρονται οι συμβολισμοί και οι βασικές έννοιες που χρησιμοποιούνται στην διπλωματική. Στην συνέχεια, δίνονται συνοπτικές πληροφορίες για το μαθηματικό υπόβαθρο που είναι απαραίτητο για την κατανόηση των εσωτερικών μηχανισμών του GCM. Ακολουθεί η ανάλυση των μαθηματικών συνιστωσών του GCM. Επίσης, παρουσιάζεται το υπόβαθρο των τρόπων λειτουργίας (mode of operation) που υιοθετούνται στον GCM. Τέλος, δίνονται συνοπτικά βασικές πληροφορίες της FPGA πλατφόρμας, Στο Κεφάλαιο 3, γίνεται μια ολοκληρωμένη ανάλυση και μελέτη του Advanced Encryption Standard (AES) και πιο συγκεκριμένα της forward cipher function με υποστηριζόμενο κλειδί 128 bit, καθώς αυτή η διεργασία αποτελεί τον βασικό συμμετρικού κλειδιού block cipher που χρησιμοποιείται στον GCM. Στο Κεφάλαιο 4, πραγματοποιείται η ανάλυση του προτύπου GCM βασισμένη στο τέταρτο recommendation του NIST. Παρουσιάζονται όλοι οι επιμέρους αλγόριθμοι που χρησιμοποιούνται καθώς και ο τρόπος με τον οποίον αυτοί αλληλεπιδρούν και συνεργάζονται για την δημιουργία του GCM αλγορίθμου. Στο τέλος του κεφαλαίου, αναφέρονται οι απαιτήσεις για key και IV που πρέπει να ικανοποιούνται για να θεωρείται ο αλγόριθμος κρυπτογραφικά ισχυρός. Στο Κεφάλαιο 5, αρχικά γίνεται μια top down ανάλυση του GCM. Την ανάλυση αυτή συμπληρώνει η δεύτερη ενότητα στην οποία παρουσιάζεται και αναλύεται η προτεινόμενη αρχιτεκτονική για την hardware υλοποίηση. Στην συνέχεια, δίνεται ο σχεδιασμός των βασικών δομικών στοιχείων του GCM. Στην τελευταία ενότητα παρουσιάζεται η συνολική αρχιτεκτονική του GCM με σκοπό την υλοποίηση για high speed απαιτήσεις. Στο Κεφάλαιο 6, δίνεται μια συνοπτική περιγραφή στα γενικότερα θέματα μια γλώσσας περιγραφής υλικού, και των εργαλείων εξομοίωσης και σύνθεσης. Στο Κεφάλαιο 7, δίνονται τα αποτέλεσμα που προέκυψαν από την εξομοίωση του VHDL κώδικα. Ακολουθούν τα αποτελέσματα της σύνθεσης από δύο διαφορετικές FPGA τεχνολογίες. Στη συνέχεια γίνεται εισαγωγή στον τρόπο με τον οποίο ο μηχανισμός πιστοποίησης και κρυπτογράφησης μηνυμάτων συνεργάζονται για την υλοποίηση του GCM και δίνεται ο τρόπος λειτουργίας του GCM μηχανισμού που υλοποιήθηκε. Ακολουθούν τα αποτελέσματα της εξομοίωσης και σύνθεσης σε δύο διαφορετικές τεχνολογίες καθώς και μια σύγκριση μεταξύ των δύο τεχνολογιών που χρησιμοποιήθηκαν για την σύνθεση. Στο Παράρτημα Α παρουσιάζεται ο τρόπος χρήσης του Xilinx ISE που χρησιμοποιήθηκε για την σύνθεση του VHDL κώδικα για την τεχνολογία Virtex-V. / This thesis proposes a hardware implementation in high speed data rates for encrypting messages based on security standard Galois / Counter Mode (GCM). The encryption algorithm Galois / Counter Mode (GCM) was adopted by the National Institute of Standards and Technology (NIST) in November 2007. In cooperation with the authentication message mechanism, the standard for online GCM mode is fully implemented. The Galois/Counter Mode of Operation (GCM) simultaneously authenticates and encrypts data at speeds that were not previously possible for both software and hardware implementations. In GCM, data integrity is achieved by chaining Galois field multiplication operations while a symmetric key block cipher such as the Advanced Encryption Standard (AES), is used to meet goals of confidentiality.
256

Examining mode of experience: implications for linear trail design and conflict management

Walker, Jamie Rae 30 September 2004 (has links)
Jacob and Schreyer (1980) define mode of experience (e.g. the degree to which participants experience an environment as focused or unfocused) as one of four major factors underlying outdoor recreation conflict. To discover the degree to which mountain bikers and hikers focus in the environment and to identify the key environmental elements and cognitive processes relevant to creating the mode of experience and underlying conflict, Visitor Employed Photography, VEP, and follow-up interviews were combined to explore mountain bikers' and hikers' perceptual experiences. Twelve mountain bikers (7 males, 5 females) rode about four and one half miles of the Lake Bryan East Loop Trail and 12 hikers (6 males, 6 females) hiked about 1.5 miles. Each participant was given a digital camera and tape recorder and was instructed to stop and take a picture of whatever they were looking at right when they heard music play. Findings indicate that mountain bikers tended to concentrate on Trail Corridor elements while forming or creating their Path/Line to travel while hikers tended to look around, scan, or take in full views of Wildlife, Vegetation, and Noises. Combined analyses suggested that mountain bikers photographed On-Trail Tread-Specific and Path/Line perceptions while hikers photographed Off/Off Distant-Views of Vegetation and Noises. Consensus existed among both for photographing On Distant at Trail Corridor elements down the Path/Line; On Distant at Trail Corridor elements Panoramic Forward; and at the Edge of Specific Vegetation elements. Interview findings indicated that participants rely on complex cognitive processes that involve focusing on many areas of the trail at one time. The participant's cue formation processes, foreground/background formation, goals, sequencing, and dynamic movement influenced their mode of experience. Using the findings, this paper presents a graphic representation of mode of experience accounting for the changes participants experience; discusses lingering appraisals' affects on participants' future perceptions during linear trail experiences; discusses conflict mitigation using trail design techniques; provides design suggestions for diminishing hiker and mountain biker conflicts; suggests an adapted ROS, Recreation Opportunity Spectrum, to manage trails for setting based outcomes from a mode of experience perspective; and discusses integrating user participation in management decisions.
257

QUANTITATIVE DIFFERENCES IN PARTICIPANTS EXPOSED TO PATTERNED, WEAK-INTENSITY ELECTROMAGNETIC FIELDS: INVESTIGATING THE SHIVA

Collins, Mark William Glister 19 March 2014 (has links)
Direct and indirect stimulation of the brain have produced a range of perceptual, motor, and cognitive experiences, including experiences historically ascribed to religious or spiritual domains. Weak intensity, extremely low frequency electromagnetic fields patterned after physiological processes have been the subject of much research and controversy. The current study examined the Shiva technology, a unique method of field production that utilizes the same fields used in previous research. Quantitative changes in brain activity were measured using quantitative electroencephalograph and subjective reports of experiences were examined. The investigation included two different configurations of the Shiva technology. Results indicated that individuals exposed to specific patterned fields exhibited different patterns of neural activity and greater reports of unusual experiences compared to a sham condition. The importance of particular enhancement of power in regions of the brain due to the sequence of different patterns of magnetic fields was a key discovery. Personality characteristics, particularly those involved with the Default Mode Network, and their relation to baseline electroencephalographic data were also examined.
258

MODAL ANALYSIS OF MEMS GYROSCOPIC SENSORS

Burnie, Marc 03 June 2010 (has links)
Microgyroscopes find popular applications in modern life, such as, vehicle navigation, inertial positioning, human body motion monitoring, etc. In this study, three unique MEMS gyroscopic sensors were investigated using experimental methods and finite element analysis (FEA) modelling, particularly their modal behaviour. The analytical, simulated and experimental results were compared and the discrepancy between resonant frequencies of the significant mode shapes was discussed. Three microfabricated gyroscopes were investigated: a thermally-actuated in-plane gyroscope, an electrostatically-actuated in-plane gyroscope and an electrostatically-actuated out-of-plane gyroscope. Numerical finite element modal analysis for these three gyroscopes was conducted using COMSOL Multiphysics. The experimental testing was conducted using a microsystem analyzer (MSA-400 PolyTec) with an integrated laser vibrometer. The simulation models predicted that the frequencies for driving and sensing modes were 4.948kHz and 5.459kHz for a thermally-actuated gyroscope, which agreed well with experimentally determined results of 5.98kHz and 6.0kHz respectively. The power requirements of a thermally-actuated gyroscope were 363.39mW to elicit a maximum peak-to-peak displacement of 4.2μm during dynamic operation. Similarly, the simulated frequencies for the driving and sensing modes were 1.170kHz and 1.644kHz for an electrostatically-actuated in-plane gyroscope, which corresponded to experimentally determined resonant frequencies 1.6kHz and 1.9kHz. Simulation for the electrostatically-actuated out-of-plane gyroscope was conducted and the frequencies for the driving and sensing modes were found to be 2.159kHz and 3.298kHz. Due to some fabrication defects, the experimental testing for this microgyroscope was not successful. Some recommendations to improve the design were provided for the future work. / Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2010-06-02 22:00:52.994
259

Biomechanically Constrained Groupwise Statistical Shape Model to Ultrasound Registration of the Lumbar Spine

Khallaghi, Siavash 28 September 2010 (has links)
Spinal needle injections for back pain management are frequently carried out in hospitals and radiological clinics. Currently, these procedures are performed under fluoroscopy or CT guidance in specialized interventional radiology facilities. As an alternative, the use of inexpensive ultrasound image guidance promises to improve the efficacy and safety of these procedures. We propose to eliminate or reduce the need for ionizing radiation, by creating and registering a statistical shape model of the lumbar vertebrae to 3D ultrasound volumes of patient, using a groupwise registration algorithm. From a total of 35 patient CT volumes, a statistical shape model of the L2, L3 and L4 vertebrae is built, including the mean shape, and principal modes of variation. The statistical shape model is registered to the 3D ultrasound by interchangeably optimizing the model parameters and their relative poses. We also use a biomechanical model to constrain the relative motion of the models throughout the registration process. Validation is performed on three tissue mimicking-phantoms designed to preserve realistic curvature of the spine. We compare pairwise and groupwise registration of the statistical shape model of the spine and demonstrate that clinically acceptable mean target error registration of 2.4 mm can be achieved with the proposed method. Registration results also show that the groupwise registration outperforms the pairwise in terms of success rate. / Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2010-09-27 20:08:01.828
260

SI - HCCI mode switching optimization using a physics based model

Schleppe, Michael N Unknown Date
No description available.

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