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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.
121

A study of Location-Based Services including design and implementation of an enhanced Friend Finder Client with mapping capabilities

Östman, Lennart January 2001 (has links)
Detta arbete behandlar mobilpositionering och relaterade tjänster, så kallade location-based services. Syftet med arbetet är att undersöka hur mobilpositionering kommer att utvecklas i takt med att nya mobilsystem tillåter mer avancerade mobila tjänster. En applikation, Finder Client har utvecklats för att kunna visa vänners positioner på en handdators karta. Kartorna som används finns i färdiga ruttplaneringsprodukter som installeras på handdatorn. Positioneringen sker via en GSM-telefon och SMS. Syftet är även att visa att man kan spara data på handdatorn för att göra intelligentare applikationer. Utvecklingen har gjorts i OPL för en Psion 5mx handdator. OPL är inbyggt i Psion och liknar språk som Pascal och Basic. Slutsatsen är att det går bra att utveckla en Finder klient för handdatorer men det vore mer användarvänligt att utveckla den för en kombinerad handator och mobiltelefon, en så kallad Smart Phone. Man kan också tänka sig att GSM-positionering blir en del av ett ruttplaneringsprogram precis som GPS-positionering är idag. En marknadsundersökning har utförts i examensarbetet. Det kan konstateras att en kombination av GSM- och GPS-positionering kommer troligen att vara lyckosammast i framtiden. De drivande krafterna inom mobilpositionering är den amerikanska statens påbud att alla mobiltelefoner ska kunna positioneras vid alarmsamtal (E911) samt att mobiltelefonoperatörerna ser tjänsterna som en ny potentiell inkomstkälla. Det är mycket svårt att säga vilka tjänster som kommer att bli populära i framtiden. Lösningar som riktar sig till ungdomar, underhållningsbranchen och mot att navigera/spåra fordon ser dock mycket intressanta ut. Det är troligt att positionering kommer att utgöra en liten del i många framtida mobila tjänster. ABSTRACT This work deals with the aspects of location-based services. The aim is to investigate how mobile positioning is going to develop in relation to the fact that new mobile system allows more advanced mobile services. An application, an enhanced Finder Client is developed. It uses maps to display friends’ positions on a handheld computer (PDA). The maps are off-the-shelf route planning products that are installed on the PDA. The positioning is made using a GSM mobile phone and SMS as a means for communication. The aim is also to show that it is possible to store large amounts of data on the PDA to make more intelligent applications. The development is performed in OPL on a Psion 5mx handheld computer. OPL is Psion’s built-in programming language, quite similar to languages like Pascal and Basic. The conclusion is that it is possible to develop a Finder Client for handheld computers but it would be more user-friendly to develop the client on a combined mobile phone and a PDA: a Smart Phone. It can also be possible to incorporate GSM positioning into the map software just as GPS positioning is a part of them today. A market overview has also been performed. The conclusion is that a combination of GSM and GPS positioning is probably the most successful solution for the future. The driving force is the Federal Communications Commissions, FCCs E911 decree, which regulates that all emergency calls from a mobile phone must be able to be positioned. Another aspect is that the mobile operators consider location-based services to be a new source for income. It is difficult to estimate which solutions that are going to be popular in the future. Services focusing on the youth, entertainment and vehicle navigation/tracking seems however to be the most interesting. It is likely to believe that mobile positioning is going to be a small part in many mobile services in the future. / Validerat; 20101217 (root)
122

Application of mobile IT in construction

Bowden, Sarah L. January 2005 (has links)
In recent years, the construction industry has been compelled to explore all possible options for improving the delivery of their products and services. Clients are now expecting a better service and projects that meet their requirements more closely. This has challenged the industry to become more efficient, integrated and more attractive, with benefits for its potential workforce and for society as a whole. Information and communication technologies (ICT) are an enabler to facilitate the improvements required for modernisation. However, due to the geographically dispersed and nomadic nature of the construction industry's workforce, many people are prevented from efficiently and effectively using the ICT tools adopted to date. Mobile technologies providing the 'last mile' connection to the point-of activity could be the missing link to help address the ongoing drive for process improvement. Although this has been a well-researched area, several barriers to mainstream adoption still exist: including a perceived lack of suitable devices; a perceived lack of computer literacy; and the perceived high cost. Through extensive industry involvement, this research has taken the theoretical idea that mobile IT use in the construction industry would be beneficial, a step further; demonstrating by means of a state of the art assessment, usability trials, case studies and demonstration projects that the barriers to mainstream adoption can be overcome. The findings of this work have been presented in four peer-reviewed papers. An ongoing dissemination programme is expected to encourage further adoption.
123

Mobiltelefonen som hjälpmedel för vuxna med ADHD / The Mobile Phone as Assistive Technology for Adults with ADHD

Hallberg, Pernilla January 2009 (has links)
<p>Syftet med uppsatsen är att bidra till att öka kunskapen om hur tekniska hjälpmedel kan användas för att underlätta vardagen för vuxna människor med ADHD.  För att åstadkomma detta görs en genomgång av vilka problem som kan föreligga vid ADHD och vilka strukturer och aktörer som finns i samhället för att erbjuda hjälp och stöd som vuxna med ADHD kan ha behov av. Därefter betraktas vilka strategier och metoder som kan vara användbara för att kompensera för de problem ADHD kan innebära och hur teknik, såväl specialtillverkade hjälpmedel som vanliga produkter, kan användas för att kompensera. En översikt görs av hur teknik kan utformas för att bli användbar, såväl generellt som mer specifikt rörande utformning av hjälpmedel. Detta åskådliggörs genom exempel från några svenska hjälpmedelsprojekt följt av en probleminventering där ett antal studiebesök och intervjuer har tjänat som en bakgrund för förståelse av den stora mängd strukturer, aktörer och hjälpmedel som är möjliga men emellanåt svårtillgängliga vägar till hjälp för vuxna med ADHD.</p><p> </p><p>De som i slutänden kan avgöra vilken nytta ett hjälpmedel innebär är brukarna själva. Deras upplevelser och erfarenheter är en ovärderlig källa till kunskap. Under arbetets gång har frågeställningen preciserats till att lyda: <em>"Hur kan vanliga mobiltelefoner användas som hjälpmedel för att underlätta vardagen för vuxna med ADHD?"</em>.<em> </em>För att besvara denna fråga har semistrukturerade riktade intervjuer genomförts med fyra kvinnor med ADHD som använder mobiltelefonen som hjälpmedel i sin vardag. Intervjuerna har transkriberats och kategoriserats för att identifiera hur mobiltelefoner används, vad som fungerar bra och mindre bra och vad kan göra att mobiltelefonen upplevs som ett fungerande hjälpmedel.</p><p> </p><p>Resultaten från bearbetning och analys av intervjuerna sammanställs i kapitlet sammanfattande analys i avsnitt med användbara funktioner, användbara egenskaper och perspektiv på stödbehov och hjälparroll. I diskussionskapitlet föreslås sedan vidare användning av resultaten i avsnitten teoretiska implikationer och praktiska implikationer. Min förhoppning är att dessa avsnitt tillsammans med de listor och tumregler som presenterats i den teoretiska referensramen skall kunna vara användbara för att identifiera behov och möjliga lösningar som kan vara värdefulla att pröva i det enskilda fallet.</p><p> </p><p>En person kan behöva stöd för att ta till vara de möjligheter mobiltelefonen erbjuder som hjälpmedel. Hjälpen kan behövas i något eller alla steg från problemidentifiering och införskaffande till införande, fortlöpande uppföljning och utvärdering av hjälpmedelsanvändningen. Stödet kan behöva vara av så väl strukturell och habiliterande art som av teknisk natur för att hjälpmedelsanvändningen skall bli så framgångsrik som är möjligt. Siktet bör vara mot vad som kan innebära kvalitet, mervärde och avlastning för individen i dennes liv, inte vad som är ADHD-symptom och hur dessa skall kompenseras.</p><p> </p><p>Vuxna med ADHD är en mycket heterogen grupp och de resultat som presenteras i uppsatsen är att betrakta som en utgångspunkt för vidare funderingar och prövning snarare än som färdiga lösningar som passar alla med ADHD.</p><p> </p>
124

Fundamental Studies on Direct Injection Nebulisers for Sample Introduction in ICP Spectrometry : Aerosol Properties, ICP Characteristics and Analytical Performance

Goitom Asfaha, Daniel January 2006 (has links)
<p>The performance of different types of nebulisers: Vulkan direct injection nebuliser (Vulkan DIN), direct injection high efficiency nebuliser (DIHEN), microconcentric nebuliser coupled to cyclonic or double pass spray chamber (MCN-C or MCN-DP, respectively) was investigated and compared when used for sample introduction to ICP-MS or ICP-OES. With ICP-OES, in axial viewing mode, intensity distributions across the radius of the plasma (radial intensity profiles) were determined for different spectral lines with Esum 1.85-15.41 eV to determine fundamental plasma properties for various matrices using Vulkan DIN and MCN-C. The results showed that with the MCN-C the ionisation temperature (Tion) was about the same across the measured region of the plasma (±3.0 mm) whereas with the Vulkan DIN the Tion was significantly lower in the centre of the plasma. A large deviation from local thermodynamic equilibrium, as well as deteriorated stability, was observed for the plasma when using the Vulkan DIN.</p><p>With ICP-MS noise power spectra (NPS) were generated to identify sources of noise. NPS showed that the magnitude of white noise for the tested sample introduction systems decreased in the following order: Vulkan DIN > DIHEN > MCN-C > MCN-DP. This order follows the decrease of mean droplet size and span of the size distribution, indicating that the white noise is caused by spatial and temporal non-uniform desolvation and ionisation. Another source of noise arose from the peristaltic pump and the magnitude of pump interference noise decreased in the following order: DIHEN > MCN-C/DP > Vulkan DIN. Mains power interference noise and 1/f noise were lower for the direct injection nebulisers compared to the spray chamber systems. The contribution or effects of these noise components on relative standard deviations of steady-state ion-count rate and isotope ratio measurements is discussed in this thesis.</p><p>Aerosols generated by the Vulkan DIN and the DIHEN were also directly characterised using Particle Dynamic Analysis. The Vulkan DIN produced particles with a mean diameter of ~30 µm and a size distribution between 2-80 µm. With the DIHEN the corresponding values were ~11 µm and 1-40 µm, respectively, with a few particles at 55-78 µm. The mean velocity of particles from the Vulkan DIN was ~10 m s-1 and from the DIHEN ~18 m s-1. The lower velocity allows longer residence time counteracting the effects of the larger droplet size.</p>
125

Fundamental Studies on Direct Injection Nebulisers for Sample Introduction in ICP Spectrometry : Aerosol Properties, ICP Characteristics and Analytical Performance

Goitom Asfaha, Daniel January 2006 (has links)
The performance of different types of nebulisers: Vulkan direct injection nebuliser (Vulkan DIN), direct injection high efficiency nebuliser (DIHEN), microconcentric nebuliser coupled to cyclonic or double pass spray chamber (MCN-C or MCN-DP, respectively) was investigated and compared when used for sample introduction to ICP-MS or ICP-OES. With ICP-OES, in axial viewing mode, intensity distributions across the radius of the plasma (radial intensity profiles) were determined for different spectral lines with Esum 1.85-15.41 eV to determine fundamental plasma properties for various matrices using Vulkan DIN and MCN-C. The results showed that with the MCN-C the ionisation temperature (Tion) was about the same across the measured region of the plasma (±3.0 mm) whereas with the Vulkan DIN the Tion was significantly lower in the centre of the plasma. A large deviation from local thermodynamic equilibrium, as well as deteriorated stability, was observed for the plasma when using the Vulkan DIN. With ICP-MS noise power spectra (NPS) were generated to identify sources of noise. NPS showed that the magnitude of white noise for the tested sample introduction systems decreased in the following order: Vulkan DIN &gt; DIHEN &gt; MCN-C &gt; MCN-DP. This order follows the decrease of mean droplet size and span of the size distribution, indicating that the white noise is caused by spatial and temporal non-uniform desolvation and ionisation. Another source of noise arose from the peristaltic pump and the magnitude of pump interference noise decreased in the following order: DIHEN &gt; MCN-C/DP &gt; Vulkan DIN. Mains power interference noise and 1/f noise were lower for the direct injection nebulisers compared to the spray chamber systems. The contribution or effects of these noise components on relative standard deviations of steady-state ion-count rate and isotope ratio measurements is discussed in this thesis. Aerosols generated by the Vulkan DIN and the DIHEN were also directly characterised using Particle Dynamic Analysis. The Vulkan DIN produced particles with a mean diameter of ~30 µm and a size distribution between 2-80 µm. With the DIHEN the corresponding values were ~11 µm and 1-40 µm, respectively, with a few particles at 55-78 µm. The mean velocity of particles from the Vulkan DIN was ~10 m s-1 and from the DIHEN ~18 m s-1. The lower velocity allows longer residence time counteracting the effects of the larger droplet size.
126

MIMO ANTENNA DESIGNS FOR WLAN APPLICATIONS

Chou, Jui-hung 22 May 2006 (has links)
In this thesis, the studies mainly focus on recent trends in novel MIMO antennas for indoor wireless communication system. Firstly, we propose a novel MIMO antenna for access-point application. This proposed antenna can reduce the lateral length of the conventional access-point antenna for MIMO application. Then, we present MIMO antenna designs for mobile devices such as PDA phones and laptop computers. Although these two devices are of different configurations, the PIFAs are applicable in these two devices, and their design rules are basically the same. Thus, for this study, the design consideration of the MIMO antenna will focus on S-parameter analysis. Detailed antenna designs and experimental results are presented and discussed in this thesis.
127

The Key Success Factors of Using Digital Devices to Promote Mobile Learning¡ÐThe Case of PDA Guidence in Taiwan¡¦s National Museums

Mah, Jui-hsuan 30 August 2006 (has links)
This study explores the application of wireless local area network (WLAN) in mobile learning. Although still in its infancy, Taiwan¡¦s government has devoted much resource on mobile learning as the extention of e-Taiwan project. National museums are among the key projects where the effectiveness of mobile learning can be soundly demonstrated. Taking national museums as observing objects, this study examines whether museum visitors appreciate WLAN environment within which personal digital assistants (PDA) operate as mobile educational tools. It further explores the key success factors that leads to successful deployment of mobile learning system. The researcher conducted a two-wave survey, firstly on museum visiters then on museum and e-learning experts for data gathering. Using analytical hierarchy process (AHP) as the research method, this study filters out the priority setting of those six categories as follows according to their significance: learning content, network connection, interface design, mareking and promotion, and business model. It also shows that the priority setting might change as a matter of time. As far as implication for education is concerned, the study suggests that, in the learning space of museum, PDA equipped with WLAN proves to be an appropriate mobile learning tool, notably useful in conducting blending learning and self-directed learning. Such finding should contribute to the understanding and further deployment of mobile learning activities in the context of museums. Keywords: wireless local area network (WLAN), mobile learning, blending learning, self-directed learning, personal digital assistant (PDA), fuzzy analytical hierarchy process (FAHP), key success factors, museum
128

Epitaxy of crystalline oxides for functional materials integration on silicon

Niu, Gang 20 October 2010 (has links) (PDF)
Oxides form a class of material which covers almost all the spectra of functionalities : dielectricity, semiconductivity, metallicity superconductivity, non-linear optics, acoustics, piezoelectricity, ferroelectricity, ferromagnetism...In this thesis, crystalline oxides have beenintegrated on the workhorse of the semiconductor industry, the silicon, by Molecular Beam Epitaxy (MBE).The first great interest of the epitaxial growth of crystalline oxides on silicon consists in the application of "high-k" dielectric for future sub-22nm CMOS technology. Gadoliniumoxide was explored in detail as a promising candidate of the alternative of SiO2. The pseudomorphic epitaxial growth of Gd2O3 on Si (111) was realized by identifying the optimal growth conditions. The Gd2O3 films show good dielectric properties and particularly an EOTof 0.73nm with a leakage current consistent with the requirements of ITRS for the sub-22nmnodes. In addition, the dielectric behavior of Gd2O3 thin films was further improved by performing PDA treatments. The second research interest on crystalline oxide/Si platform results from its potential application for the "More than Moore" and "Heterogeneous integration" technologies. TheSrTiO3/Si (001) was intensively studied as a paradigm of the integration of oxides on semiconductors. The crystallinity, interface and surface qualities and relaxation process of the STO films on silicon grown at the optimal conditions were investigated and analyzed. Several optimized growth processes were carried out and compared. Finally a "substrate-like" STO thin film was obtained on the silicon substrate with good crystallinity and atomic flat surface. Based on the Gd2O3/Si and SrTiO3/Si templates, diverse functionalities were integrated on the silicon substrate, such as ferro-(piezo-)electricity (BaTiO3, PZT and PMN-PT),ferromagnetism (LSMO) and optoelectronics (Ge). These functional materials epitaxially grown on Si can be widely used for storage memories, lasers and solar cells, etc.
129

Solides et interfaces : des outils de modélisation et d'analyse de la complexité en matière condensée

Filhol, Jean-Sébastien 14 October 2010 (has links) (PDF)
Ce manuscrit présente différentes approches permettant la modélisation et la compréhension de la complexité structurelle, électronique, dynamique de systèmes condensés. En particulier, le premier chapitre traite le l'organisation et de la réactivité des surfaces et interfaces métalliques de grande taille, le second de la prise en compte des effets électrochimiques à la fois pour les systèmes condensés, et pour les interfaces par modification du potentiel électrochimique. Le troisième est consacré aux effets du polymorphisme de grands polymères organiques sur leurs propriétés macroscopiques. Le chapitre final s'intéresse au pendant enseignement de cette recherche, utilisant de nouvelles approches pédagogiques qui permettent la synthétise par les étudiants, dès la première année universitaire, de matériaux de haute technologie.
130

Conception des circuits de polarisation des détecteurs et de maintien de la tension de base du LabPET II

Panier, Sylvain January 2014 (has links)
Par le passé, la collaboration entre le Centre d'Imagerie Médicale de Sherbrooke (CIMS) et le Groupe de Recherche en Appareillage Médicale de Sherbrooke (GRAMS) a permis de développer le scanner LabPET. Celui-ci fut le premier scanner de Tomographie d'Émission par Positrons (TEP) commercial utilisant des photodiodes à effet avalanche (PDA) comme détecteur. Depuis, cette collaboration a permis de faire évoluer le scanner afin d'améliorer cette modalité d'imagerie et d'y ajouter la tomodensitométrie (TDM). Les attentes pour la prochaine génération du scanner sont donc grandes. Cette nouvelle génération du scanner, le LabPET II, verra les deux modalités nativement intégrées et elles utiliseront la même chaine de détection. Ce scanner se verra doté de nouveaux détecteurs organisés en matrices de 64 cristaux de 1,1 par 1,1 mm². Cette nouvelle matrice, associée à ses deux matrices de 32 PDA, a prouvé sa capacité à fournir une résolution spatiale inférieure au millimètre. L'utilisation de ce nouveau module de détection pourra donc permettre au LabPET II d'être le premier scanner bimodal (TEP/TDM) commercial atteignant une résolution submillimétrique. Ce scanner permettra de s'approcher un peu plus de la résolution spatiale ultime en TEP tout en permettant une bonne localisation anatomique grâce à l'ajout d'une imagerie TDM rudimentaire. Pour atteindre ces objectifs, une intégration complète de l'électronique frontale a été nécessaire. Dans les versions précédentes, seuls les préamplificateurs de charge et les filtres de mise en forme étaient intégrés; dans cette nouvelle version, toute l'électronique analogique ainsi que la numérisation et les liens de communications devront être intégrés. Pour ce faire, la technique de temps de survol au-dessus d'un seuil (ou ToT pour «Time-over-Threshold») a été préférée à la solution utilisée par le LabPET I qui nécessitait un convertisseur analogique-numérique par canal. La contrepartie de cette solution est l'obligation de maintenir la tension de base à une valeur fixe et commune à tous les canaux. Le circuit de polarisation des PDA a aussi dû être intégré dans l'ASIC, car il occupait énormément de place sur la carte d'électronique frontale du LabPET 1. Dans ce mémoire seront décrits la conception, l'intégration et les tests de ces deux circuits du système. Ils ont démontré leur efficacité tout en n'occupant que très peu de place dans le circuit intégré spécialisé (ASIC) du «module de détection». Au vu des sources bibliographiques recensées, le module de détection du LabPET II devrait être l'un de ceux ayant la plus forte densité de canaux (environ 45 par centimètre carré) et le seul combinant électronique analogique faible bruit, numérique et haute tension (~450 V). La réalisation de cette nouvelle génération devrait permettre au partenariat CIMS/GRAMS de réaffirmer leur position de leader dans le domaine en améliorant les outils d'imagerie à la disposition des chercheurs en médecine préclinique.

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