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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

Tusen röda plastbåtar : En studie av framgångsrik gerillamarknadsföring

Grahn, Magdalena, Jörgensen, Sanna, Olsson, Jeanette January 2010 (has links)
Background: Swedish consumers are daily bombarded with 1500 advertising messages. 22 percent of the Swedish people are avoiding all advertising in traditional media according to SIFO's research. To master this problem innovative methods are a necessity to reach consumers. Guerrilla marketing is such a method. Purpose: The purpose of this dissertation is to describe the components and the activities that asuccessful guerrilla campaign consists of. He purpose is also to examine the motives behind theseactivities, why they were chosen and what objectives they were supposed to accomplish. Theambition is to find success factors for guerrilla marketing that result in publicity and increasedrecognition. Limitations: The Swedish market where a collaboration between two companies, Miami GuerrillaMarketing (Miami) and Stena Line, has been examined in a case study. The case study focuses on two successful guerrilla campaigns, 2008 and 2009, which resulted in publicity and increasedrecognition. Method: Case study Conclusion: A number of factors that lead to successful guerilla marketing, which gains publicityand increased recognition, have been identified in this dissertation. These are to: chose a new marketing communications strategy, chock and surprise the customers, use the novelty effect,generate strong emotions, match the media selection with the target audience and use uncon-­ventional media. Suggestion for further research: Experiment of guerrilla marketing in combination with traditionalmarketing and also studies of the effectiveness of the method.
32

Aircraft Trajectory Optimization with Tactical Constraints

Norsell, Martin January 2004 (has links)
<p>Aircrafttrajectory optimization is traditionally used forminimizing fuel consumption or time when going from one flightstate to another. This thesis presents a possible approach toincorporate tactical constraints in aircraft trajectoryoptimization.</p><p>The stealth technology of today focuses on making thetactics already in use more effective. Since tactics andstealth are closely interrelated, new and better results may beobtained if both aspects are considered simultaneously. Simplyreducing the radar cross section area in some directionswithout considering tactical aspects may result in little, ifany, improvement.</p><p>Flight tests have been performed in cooperation withEricsson Microwave Systems and the Swedish Air Force FlightAcademy. The aircraft used was the subsonic jet trainer Saab105, designated SK60 by the Swedish Air Force. The results showa decrease of 40% in the time interval between the instant theaircraft was first detected until it could pass above the radarstation. This corresponds to a reduced radar cross section(RCS) in the direction from the aircraft to the radar of almost90%, if classical RCS reduction techniques would have beenapplied.</p><p>If a modern aircraft with stealth properties would be used,the proposed methodology is believed to increase the possibleimprovements further. This is because the variation of themagnitude of RCS in different directions is greater for a shapeoptimized aircraft, which is the property exploited by thedeveloped method.</p><p>The methods presented are indeed an approach utilizing theideas of the network centric warfare (NCW) concept. Themethodology presented depends on accurate information about theadversary, while also providing up-to-date information to theother users in the information network.</p><p>The thesis focuses on aircraft but the methods are generaland may be adapted for missiles, shipsor land vehicles. Theproposed methods are also economically viable since they areuseful for existing platforms without costly modifications. Themethods presented are not limited to radar threats only. Thereasons for using radar in this thesis are the availablenon-classified data and that radar is known to pose a majorthreat against aircraft.</p>
33

Lipossomas contendo ácido caurenoico ou extrato de Copaifera langsdorffii: desenvolvimento, caracterização e atividades antitumoral e tripanocida / Loaded liposomes with kaurenoic acid or Copaifera langsdorffii extract: development, characterization, antitumor and tripanocide activities

Ana Rita de Mello Costa 18 April 2016 (has links)
A Copaifera langsdorffii é uma das plantas de incentivo governamental para pesquisas científicas e possui diversas atividades biológicas. Em especial, as atividades antitumoral e tripanocida foram abordadas neste estudo tendo o ácido caurenoico (AC) como marcador. Devido à escassa literatura sobre a extração do AC e à sua baixa solubilidade, sua extração foi estudada com solvente orgânico e por fluido supercrítico. A extração por fluido supercrítico é vantajosa já que não fornece extratos com resíduos de solventes orgânicos e é ecologicamente correta. Visto as atividades antitumoral e tripanocida do AC e estas atividades serem objeto de estudo nacional e mundial, o AC foi inserido em lipossomas convencionais e furtivos com a finalidade de torná-lo mais biodisponível, permitir seu alcance ao sítio-alvo e diminuir seus efeitos adversos. Assim, os objetivos deste trabalho foram segmentados em três vertentes: a) realizar o estudo e otimização da extração do ácido caurenoico a partir das folhas de C. langsdorffii, b) obter lipossomas convencionais, secá-los pelos métodos de secagem liofilização (FD), spray drying (SD) e spray freeze drying (SFD), comparar suas características físico-químicas e avaliar suas atividade antitumoral e tripanocida, c) obter lipossomas furtivos e avaliar sua seletividade tumoral. De maneira geral, os resultados das extrações sólido-líquido e por fluido supercrítico apresentaram boa seletividade e eficiência visto que foram capazes de fornecer extratos com aproximadamente 20% de AC. A extração por fluido supercrítico foi mais eficaz extraindo 26,2% de AC. Já os lipossomas convencionais secos por SD e SFD apresentaram-se mais semelhantes entre si quanto à propriedade de fluxo e morfologia, à interação do AC com os componentes da bicamada lipídica e à dissolução/ liberação que quando secos por FD. Os três métodos de secagem foram capazes de prolongar em seis meses a estabilidade do AC nos lipossomas quando comparado com a dispersão aquosa. Os lipossomas convencionais secos apresentaram citotoxicidade maior frente a células tumorais e menor frente a células normais quando carregados com o AC e comparados com os lipossomas convencionais vazios (sem AC). Foi possível sintetizar com sucesso o lipídeo ligado ao polietilenoglicol e ao ácido fólico com o intuito de preparar os lipossomas furtivos. Entretanto, estes lipossomas não apresentaram ação antitumoral seletiva quando comparados às células normais. / Copaifera langsdorffii is one of the Brazilian plants which receives governmental support for scientific researches and also presents several biological activities. The kaurenoic acid (KA) is a diterpenic acid constituent of this specie that presents, in special, antitumoral and tripanocide activities which were taken into account in this study. Due to the lack of KA extraction from C. langsdorffii leaves in the literature and to KA low solubility, its extraction was studied using solid-liquid and supercritical fluid extraction methods. The supercritical fluid extraction is advantageous since provides solvent-free extracts and is an environment friendly method. Since KA is antitumoral and tripanocide and both activities are subject of national and internacional studies, in this study, KA was added in conventional and stealth liposomes in order to increase its biodiponibility, to allow it reaching the target tissue and decrease its adverse effects. So, this work was divided in three segments: a) study and optimize the KA extraction from C. langsdorffii leaves by solid-liquid (SLE) and supercritical fluid (SFE) extraction methods, b) obtain conventional liposomes, dry them by freeze drying (FD), spray drying (SD) and spray freeze drying (SFD), compare their physico-chemical features and evaluate their antitumor and tripanocide activities, c) obtain stealth liposomes and evaluate their selective tumor activity. In a general way, the extraction methods result in high KA selective extraction by both SLE and SFE since they were able to extract nearly 20% of KA. The SFE was a bit more efficacious than SLE providing 26,2% of KA. Conventional liposomes dried by SD and SFD were more similar in fluidity and morphology, KA and liposome lipid compounds interaction and dissolution/ release than liposomes dried by FD. The three drying methods provided more stable liposomes than the aqueous solution liposomes. Dried conventional liposomes presented higher cytotoxicity to tumor cells and lower one to normal cells when loaded with KA than unloaded conventional liposomes. The lipid linked to poliethyleneglycol and to folic acid to prepare stealth liposomes were successfully synthesized. However, the stealth liposomes did not presented selective antitumor action in relation to normal cells.
34

Étude des interactions élasto-acoustiques dans des métamatériaux formés d'inclusions résonnantes réparties aléatoirement / Study of the acoustical-elastic interactions in metamaterials containing randomly distributed resonant inclusions

Lepert, Guillaume 11 December 2013 (has links)
La discrétion acoustique est un enjeu majeur dans le domaine de la défense navale. Dans ce contexte, DCNS Research souhaite évaluer la capacité des métamatériaux acoustiques aléatoires localement résonnants à constituer une rupture technologique, comparativement aux matériaux anéchoïques actuels. Nous nous proposons de dimensionner, suite à une étude paramétrique conséquente, des structures contenant une répartition aléatoire d’inclusions sphériques. Des échantillons de matériaux localement résonnants ont été fabriqués. Leur réponse acoustique a été mesurée et confrontée aux prédictions issues de modèle. L’impact des résonances des inclusions et de l’angle d’incidence a été mis en évidence. Enfin, une méthode d’identification de leurs propriétés effectives a été développée à partir de mesures en réflexion et en transmission. Elle repose sur une configuration expérimentale originale. Des difficultés liées à l’extraction de la masse volumique dynamique sont mises en exergue. / Stealth is a major issue in naval defence. In this context, DCNS Research wants to know if locally-resonant acoustic metamaterials represent a technological breakthrough in comparison to current anechoic materials. We propose here a design of structures with randomly distributed spheres, based on a consequent parametric study. Samples of locally resonant materials were manufactured. Then, their acoustic response has been measured and compared to predictions based on multiple scattering theories. The presence of resonances and the impact of a non-null incidence angle have been highlighted. Finally, we developed a characterization method of the effective properties, from measurements of coefficients of reflection and transmission. Its design is based on an originally experimental setup. Difficulties coming from the retrieval of the dynamic mass density have been showed.
35

Metasurface-Based Techniques for Broadband Radar Cross-Section Reduction of Complex Structures

January 2020 (has links)
abstract: Within the past two decades, metasurfaces, with their unique ability to tailor the wavefront, have attracted scientific attention. Along with many other research areas, RADAR cross-section (RCS)-reduction techniques have also benefited from metasurface technology. In this dissertation, a novel technique to synthesize the RCS-reduction metasurfaces is presented. This technique unifies the two most widely studied and two well-established modern RCS-reduction methods: checkerboard RCS-reduction andgradient-index RCS-reduction. It also overcomes the limitations associated with these RCS-reduction methods. It synthesizes the RCS-reduction metasurfaces, which can be juxtaposed with almost any existing metasurface, to reduce its RCS. The proposed technique is fundamentally based on scattering cancellation. Finally, an example of the RCS-reduction metasurface has been synthesized and introduced to reduce the RCS of an existing high-gain metasurface ground plane. After that, various ways of obtaining ultrabroadband RCS-reduction using the same technique are proposed, which overcome the fundamental limitation of the conventional checkerboard metasurfaces, where the reflection phase difference of (180+-37) degrees is required to achieve 10-dB RCS reduction. First, the guideline on how to select Artificial Magnetic Conductors (AMCs) is explained with an example of a blended checkerboard architecture where a 10-dB RCS reduction is observed over 83% of the bandwidth. Further, by modifying the architecture of the blended checkerboard metasurface, the 10-dB RCS reduction bandwidth increased to 91% fractional bandwidth. All the proposed architectures are validated using measured data for fabricated prototypes. Critical steps for designing the ultrabroadband RCS reduction checkerboard surface are summarized. Finally, a broadband technique to reduce the RCS of complex targets is presented. By using the proposed technique, the problem of reducing the RCS contribution from such multiple-bounces simplifies to identifying and implementing a set of orthogonal functions. Robust guidelines for avoiding grating lobes are provided using array theory. The 90 degree dihedral corner is used to verify the proposed technique. Measurements are reported for a fabricated prototype, where a 70% RCS-reduction bandwidth is observed. To generalize the method, a 45 degree dihedral corner, with a quadruple-bounce mechanism, is considered. Generalized guidelines are summarized and applied to reduce the RCS of complex targets using the proposed method. / Dissertation/Thesis / Doctoral Dissertation Electrical Engineering 2020
36

Security Evaluation of Intel's Active Management Technology

Ververis, Vassilios January 2010 (has links)
Intel’s Active Management Technology (AMT) is, a hardware-based platform for remotely managing and securing personal computers out of band. AMT is available in most desktop and notebooks PCs equipped with an Intel Core 2, Centrino, or Centrino 2 processors with support for vPro technology. AMT operates independently of the platform processor and operating system. Remote platform management applications can access AMT securely, even when the platform is turned off, as long as the platform is connected to power supply and to a network. Developers can build applications that utilize AMT using the application programming interface (API) provided by Intel. While this might seem to enable creation of a powerful management tool, a secure infrastructure that is secure against insider and outsider attacks on an enterprise network is difficult. Unfortunately this technology can also potentially be used to create a powerful backdoor that is easily deployed and offers numerous features due to its almost unlimited permissions since the platform can be managed even though it is powered off. / Intel Active Management Technology (AMT) är en hårdvarubaserad plattform för avlägset att hantera och säkra datorer utanför bandet. AMT är tillgänglig de flesta stationära och bärbara dator utrustad med en Intel Core 2, Centrino, eller Centrino 2 processorer med stöd för vPro-teknik. AMT driver oberoende av plattform processor och operativsystem. Remote optimera hanteringen ansökningar kan komma åt AMT säkert, även om Plattformen är avstängd, så länge som plattform är ansluten till linjen makt och till ett nätverk. Utvecklare kan bygga applikationer som utnyttjar AMT använder Application Programming Interface från Intel. Även detta kan verkar för att möjliggöra skapandet av ett kraftfullt verktyg i förvaltningen, faktiskt skapar en säker infrastruktur som är säkert mot insider och outsider angrepp på företagets nätverk är svårt. Tyvärr har denna teknik kan komma i används för att skapa en kraftfull rootkit som är lätt att iordningställas och erbjuder flera egenskaper på grund av dess nästan obegränsade tillstånd eftersom plattformen kan lyckades även om den är avstängd.
37

Examination of first person stealth games through content analysis andcomparison : Thief Gold compared to subsequent gamesfeaturing a similar design

Pålsson Abrahamsson, Anton January 2023 (has links)
There are multiple games which can be classified as “first-person stealth” and an early game in this genre called Thief Gold has been directly influential in it. Defining the genre through certain qualifiers and using games which have directly been stated tohave been influenced by Thief Gold, Thief Gold has here beencompared to six subsequent games in the genre. What has been discovered is that while core similarities always exist, the same problems have different solutions depending on the overall designfor individual games.
38

Social Movements and Health: The Benefits of Being Involved

Emley, Elizabeth A. 19 April 2017 (has links)
No description available.
39

Thwarting Network Stealth Worms in Computer Networks through Biological Epidemiology

Hall, Kristopher Joseph 12 June 2006 (has links)
This research developed a system, Rx, to provide early identification and effective control of network stealth worms in digital networks through techniques based on biological epidemiology. Network stealth worms comprise a class of surreptitious, self-propagating code that spread over network connections by exploiting security vulnerabilities in hosts. Past outbreaks due to traditional worms subverted hundreds of thousands of machines. Network stealth worms exacerbate that threat by using clandestine methods to maintain a persistent presence in the network. Biological epidemiology was shown to support the real-time detection, characterization, forecasting, and containment of network stealth worms. Epidemiology describes a scientific methodology in biology that seeks to understand, explain, and control disease. Bio-mathematical modeling led to the development of a mechanism for digital networks to identify worm infection behavior buried in anomaly data, to characterize a worm, and to forecast the temporal spread of a worm. Demographic analysis of the infected hosts revealed the subset of vulnerable machines within the population. The automated response of advanced quarantine used this information to control the spread of an identified worm by isolating both infected and vulnerable machines. The novel contributions of this research included the identification of a network stealth worm at the network-level based on end-host reports while simultaneously characterizing and forecasting the spread of the worm. Additionally, this task offered the technique of advanced quarantine through demographic analysis of the population. This work resulted in a scalable, fault-tolerant strategy that dramatically enhanced the survival rate of network hosts under attack by a stealth worm. Moreover, this approach did not require new hardware, changes to existing protocols, or participation outside the implementing organization. This research showed application to a wider range of challenges. The bio-mathematical models are extensible, allowing Rx to respond to variations on the self-propagating code presented here. The approach is applicable to other forms of malware beyond self-propagating code by interchanging the epidemic model with one more appropriate. Lastly, the strategy allowed anomaly detectors to be sensitive to lower reporting thresholds and a variety of often benign yet potentially useful events. / Ph. D.
40

Studium membránových vlastností liposomálních systémů pomocí fluorescenční spektroskopie / Study of membrane properties of liposomal systems using fluorescence spectroscopy

Zbořilová, Hana January 2021 (has links)
The presented diploma thesis is focused on the preparation, characterization and study of membrane properties of liposomal systems which were composed of the neutral phosphatidylcholine (DPPC), cholesterol, negatively charged phosphatidylglycerol (DPPG), polyethylenglycol bounded to phosphatidylethanolamine (PEG5000–PE) and polycation N,N,N-trimethylchitosan (TMC). The influence of individual components and their concentrations on the average particle size, zeta potential and changes in the outer and inner part of the bilayer was investigated. In this matter, methods of dynamic and electrophoretic light scattering and fluorescence spectroscopy with the application of laurdan and DPH probes were used. Based on the above-mentioned parameters, concentrations of components that most suitably influence properties of liposomes in terms of the intended application were selected for the definite complex. It was managed to prepare a liposomal complex stealth liposome–N,N,N-trimethylchitosan, which, due to the optimized composition, could have suitable attributes as a drug delivery system for inhalation administration of biologically active substances.

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