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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.
21

Untersuchung von Entwicklungs- und Transferprozessen beim flüssigtonerbasierten ferroelektrischen Druckverfahren

Reuter, Susann 24 April 2009 (has links)
Auch im Zeitalter globaler Verfügbarkeit von Informationen in digitaler Form wird weiterhin gedruckt, denn zahlreiche Druckprodukte sind im Alltag bewährt und nur schwer zu ersetzen. Doch die Anforderungen an die Druckindustrie haben sich in den letzten Jahren deutlich gewandelt: Der Trend geht zu kleineren, differenzierten Auflagen bis hin zum personalisierten Drucken. Daraus erwächst die Forderung nach Technologien, die einen schnellen Wechsel zwischen den einzelnen Aufträgen ermöglichen. In dieser Arbeit wird ein Druckverfahren beschrieben, in dem als Bildträger ferroelektrische Keramikschichten eingesetzt werden. Diese Schichten lassen sich lokal umpolarisieren und ermöglichen so die Realisierung einer informationsgesteuerten Modifikation des elektrischen Oberflächenpotenzials. Die einzelnen Prozessschritte des Verfahrens werden kurz diskutiert und insbesondere die Teilprozesse der Entwicklung und des Transfers näher untersucht. Zur Beschreibung von elektrisch determinierten Transportvorgängen in elektrostatischen Druckverfahren wird ein einfaches Potenzialstufenmodell vorgeschlagen, das die gezielte Auslegung und Optimierung von einzelnen Systemkomponenten ermöglicht. Der Entwicklungsvorgang an ferroelektrischen Keramikschichten unterliegt dabei grundsätzlich den gleichen physikalischen Zusammenhängen wie die Entwicklung in anderen elektrografischen und elektrofotografischen Verfahren. Als Druckstoff wurden Flüssigtoner eingesetzt, die wegen ihrer kleinen Partikelgröße eine sehr gute Bildqualität erwarten lassen. Es werden grundsätzliche Modelle zur Ladungsentstehung an Tonerteilchen in nichtwässrigen Dispersionen zusammenfassend vorgestellt und eigene Untersuchungen zur Charakterisierung der elektrophoretischen Beweglichkeit und der Ladung pro Masse diskutiert. Für die Beschreibung der Transferprozesse zur Übertragung des Tonerbildes auf den Bedruckstoff werden Darstellungen aus der konventionellen Drucktechnik mit den für Trockentoner entwickelten Vorstellungen bezüglich der elektrostatischen Verhältnisse verknüpft. Der Einfluss der elektrischen Papiereigenschaften auf die erreichbare optische Dichte wird in eigenen Untersuchungen exemplarisch gezeigt. Unter Berücksichtigung der Forderung nach konstanten Bedingungen für die Entwicklung des Tonerbildes werden Optimierungskriterien für die Auslegung des Transferzylinders abgeleitet, und ein verbesserter Transferzylinder konnte erfolgreich getestet werden.
22

Oberflächenspezifische Adsorption von Peptiden zur Funktionalisierung gedruckter Muster

Große, Steffi 08 February 2017 (has links)
Im Rahmen der vorliegenden Arbeit wird eine neue, kostengünstige und effiziente Strategie zur selektiven Beschichtung gedruckter Muster auf Papier entwickelt. Mittels Phagen-Display werden Peptide identifiziert, die materialspezifische Adsorption zeigen und effektiv zwischen Cellulose als Hauptbestandteil von Papier und dem Toner eines mit einem handelsüblichen Laserdrucker gedruckten Musters unterscheiden können. Diese genetisch selektierten 12mer Peptide können selektiv entweder nicht bedruckte Cellulose oder gedruckte Tonerstrukturen beschichten. Es werden vielfältige Adsorptionsuntersuchungen einzelner Peptide an den jeweiligen separaten Oberflächen und an gedruckten Mustern durchgeführt und diskutiert. Des Weiteren wird eine Ligationschemie mit Triazolindion genutzt, um z. Bsp. Farbstoffe oder funktionale Peptide selektiv auf einer Oberflächenbeschichtung zu lokalisieren. Diese Methodik bietet einen einfachen Zugang zur Funktionalisierung von Mustern auf papierbasierten Materialien, wodurch neue Wege zur Realisierung kostengünstiger diagnostischer oder biomedizinischer Geräte aufgezeigt werden können. / Within the scope of this thesis, a new, cost-effective and efficient strategy for the selective coating of printed patterns on paper is developed. Phage display biopanning identifies peptides that show material selective adsorption, effectively distinguishing between cellulose of paper and printed toner of standard office laser printers. These genetically selected 12mer peptides can selectively coat either non-printed cellulose or printed toner patterns. Numerous adsorption studies of individual peptides on the respective separated surfaces and on printed patterns are carried out and discussed. Furthermore, triazolindione ligation chemistry is exploited to introduce e.g. dyes or functional peptides selectively to the coatings. The strategy offers an easy access toward patterned functionalization of paper based materials, which potentially is of relevance for low cost diagnostics or biomedical devices.
23

Creating temperature stimulated paper muscles by printing and lamination

Holmberg, Veronica January 2008 (has links)
<p>A paper that shows motion when being exposed to heat has in this study been called a paper muscle. A paper muscle can be used for many different applications, e.g. smart advertisement or indicators in printed paper products. The muscles created in the present work were prepared by gluing or printing a polymer layer onto paper. The polymer layers consisted of MELINEX, MYLAR or toner, which are known to expand when exposed to heat. Furthermore, all three material systems showed bending when exposed to heat.</p><p>A mechanical bilayer model was implemented and used to quantitatively study the parameters that influence the bending of the muscles. The model indicated that the dimensional changes of the polymer layers relative to that of the copy paper was found to be approximately 0,1-0,5 % within the temperature range 23-60 °C. The experiments showed that the combined dimensional changes within the polymer and paper layers were not linear with respect to temperature, and that there was a significant difference in bending for muscles cut in the MD and in the CD. Also, when assuming that the polymer is the active component, the observed coefficient of thermal expansion was a factor ~10 greater compared to published literature data. These findings led to the conclusion that it was indeed the dimensional changes within the paper that were the dominant cause of the bending. This was confirmed by a muscle, comprising a bilayer of paper cut in the MD and the CD, which bended when exposed to heat. The results also indicate that a large part of the bending could be attributed to the hygrocontraction of paper.</p>
24

Creating temperature stimulated paper muscles by printing and lamination

Holmberg, Veronica January 2008 (has links)
A paper that shows motion when being exposed to heat has in this study been called a paper muscle. A paper muscle can be used for many different applications, e.g. smart advertisement or indicators in printed paper products. The muscles created in the present work were prepared by gluing or printing a polymer layer onto paper. The polymer layers consisted of MELINEX, MYLAR or toner, which are known to expand when exposed to heat. Furthermore, all three material systems showed bending when exposed to heat. A mechanical bilayer model was implemented and used to quantitatively study the parameters that influence the bending of the muscles. The model indicated that the dimensional changes of the polymer layers relative to that of the copy paper was found to be approximately 0,1-0,5 % within the temperature range 23-60 °C. The experiments showed that the combined dimensional changes within the polymer and paper layers were not linear with respect to temperature, and that there was a significant difference in bending for muscles cut in the MD and in the CD. Also, when assuming that the polymer is the active component, the observed coefficient of thermal expansion was a factor ~10 greater compared to published literature data. These findings led to the conclusion that it was indeed the dimensional changes within the paper that were the dominant cause of the bending. This was confirmed by a muscle, comprising a bilayer of paper cut in the MD and the CD, which bended when exposed to heat. The results also indicate that a large part of the bending could be attributed to the hygrocontraction of paper.
25

Análises genéticas em sistemas microfabricados / Genetic analysis in microfabricated systems

Duarte, Gabriela Rodrigues Mendes 30 July 2010 (has links)
A produção de microssistemas de análises totais (&micro;TAS) tem sido objeto de esforços intensos pela comunidade científica. A necessidade de produção de uma plataforma que realize extração, amplificação e separação de DNA--um verdadeiro \"lab on a chip\"--é impulsionada pelas vantagens associadas com as análises em plataformas miniaturizadas. Esta Tese foca no desenvolvimento de métodos para análises de DNA em dispositivos microfluídicos que podem ser associados em &micro;TAS. Inicialmente, foi feito o desenvolvimento de um novo método de extração em fase sólida em que a eficiência de extração depende da manipulação magnética das partículas e não do fluxo da solução através da fase sólida. A utilidade desta técnica em isolar DNA puro de alta qualidade (amplificável) a partir de uma amostra biológica complexa foi demonstrada através da purificação de DNA a partir de sangue total e a subsequente amplificação do fragmento do gene &beta;-globina. A técnica descrita é rápida, simples e eficiente, permitindo uma recuperação de mais de 60% de DNA a partir de 600 nL de sangue em concentração suficiente para amplificação via reação em cadeia da polimerase (PCR). Após o desenvolvimento da extração dinâmica de DNA em fase sólida (dSPE) em microchip de vidro, o método foi adaptado para o uso em microchips de poliéster-toner (PT). Além da extração, a amplificação e separação de DNA também foram realizadas em microchips de PT. O processo convencional de fabricação dos dispositivos de PT produz canais com 12 &micro;m de profundidade. Este trabalho descreve um novo processo de fabricação dos microchips de PT com canais mais profundos. Uma cortadora a laser de CO2 é usada para definir a estrutura desejada no filme de poliéster recoberto com toner. Estes filmes de poliéster recobertos com toner e os canais recortados são utilizados com partes intermediárias no microchip. A tampa e a base (filmes de poliéster) são laminadas juntamente com as partes intermediárias. Desta forma microchips com canais mais profundos podem ser criados. Microchips com 4 filmes de poliéster (base, tampa, e dois filmes centrais) foram utilizados para realizar dSPE. Estes microchips possuem canais com ~270 &micro;m de profundidade. A dSPE adaptada para os microchips de PT demonstrou ser capaz de extrair eficientemente DNA (~65%), e o DNA purificado apresentou qualidade suficiente para PCR. A PCR realizada em microchips de PT demonstrou que os dispositivos de PT são compatíveis com os reagentes da PCR e o sucesso da reação de PCR foi demonstrado através da amplificação do fragmento de 520 pares de bases do &lambda;-DNA. A possibilidade de manipular diferentes soluções que são necessárias para realizar a extração e a PCR demonstra o grande potencial desta plataforma para realizar análises genéticas. Além da extração e amplificação, a separação também foi demonstrada nos dispositivos de PT. Duas integrações foram feitas nos microchips de PT, dSPE-PCR e PCR-separação. Na primeira integração a dSPE e PCR foram realizadas em uma única câmara, e a amplificação do fragmento de 520 pb do &lambda;-DNA foi demonstrada. Na segunda integração, o dispositivo foi fabricado com espessuras diferentes para os diferentes domínios. No domínio da PCR as câmaras possuem profundidade de ~270 &micro;m de profundidade, e para o domínio da eletroforese os canais apresentam 12 &micro;m de profundidade. A integração realizada sem válvulas foi demonstrada através da amplificação e detecção do fragmento de 520 pb do &lambda;-DNA em um mesmo microchip. Este trabalho demonstra o grande potencial dos microchips de PT para produzir dispositivos descartáveis totalmente integrados para análise genética. / Efforts to develop a microfluidic-based total analysis system (&micro;TAS) have been intense in the scientific community. The goal of achieving a device comprising DNA extraction, amplification, and detection in a single device, a true \"lab on a chip,\" is driven by the substantial advantages associated with such a device. This Thesis focus on development of methods for DNA analysis on microdevices, that can be associated with &micro;TAS. Sequentially, the first step was the development of a novel solid-phase extraction technique in which DNA is bound and eluted from magnetic silica beads in a manner that efficiency is dependent on the magnetic manipulation of the beads and not on the flow of solution through a packed bed. The utility of this technique in the isolation of reasonably pure, PCR-amplifiable DNA from complex samples is shown by isolating DNA from whole human blood, and subsequently amplifying a fragment of the &beta;-globin gene. The technique described here is rapid, simple, and efficient, allowing for recovery of more than 60% of DNA from 600 nL of blood at a concentration which is suitable for PCR amplification. The second step was the use of polyester-toner (PT) microchips for DNA analysis (extraction, PCR and separation). The laser-printing of toner onto polyester films has been shown to be effective for generating PT microfluidic devices with channel depths on the order of 12 &micro;m. We describe a novel and innovative process that allows for the production of multilayer PT microdevices with substantially larger channel depths. Utilizing a CO2 laser to create the microchannel in polyester sheets containing a uniform layer of printed toner, multilayer devices can easily be constructed by sandwiching the channel layer between uncoated cover sheets of polyester containing precut access holes. The process allows for the fabrication of channels several hundred microns in depth, with ~270 &micro;m deep microchannels utilized here to demonstrate the effectiveness of multilayer PT microchips for dynamic solid phase extraction (dSPE) and PCR amplification. Dynamic SPE adapted for PT microchip was able to recover more than 65% of DNA from 600 nL of blood and the DNA was compatible with downstream microchip-based PCR amplification. The compatibility of PT microchips was demonstrated by successful amplification of a 520 bp fragment of &lambda;-phage DNA. The ability to handle the diverse chemistries associated with DNA purtification and extraction is a testimony to potential utility of PT microchips beyond separations, and presents a promising new platform for genetic analysis that is low cost and easy to fabricate. Two integrations were carrying out on PT microchip, dSPE - PCR and PCR-ME. The first integration was made in a single chamber and the amplification of 520 bp fragment of &lambda;-phage was demonstrated. The second integration describes a process that allows the production of a multidomain microchip with different channel depths for the different domains for genetic analysis. The final device was made by the conventional sandwiching of the four polyester films of the PCR domain with the two polyester films for the electrophoresis domain. The successful valveless integration of PCR and separation was demonstrated by amplification and detection of a 520 bp fragment of &lambda;-phage DNA. This work shows the enormous potential of PT microchips to be used for total genetic analysis.
26

Análises genéticas em sistemas microfabricados / Genetic analysis in microfabricated systems

Gabriela Rodrigues Mendes Duarte 30 July 2010 (has links)
A produção de microssistemas de análises totais (&micro;TAS) tem sido objeto de esforços intensos pela comunidade científica. A necessidade de produção de uma plataforma que realize extração, amplificação e separação de DNA--um verdadeiro \"lab on a chip\"--é impulsionada pelas vantagens associadas com as análises em plataformas miniaturizadas. Esta Tese foca no desenvolvimento de métodos para análises de DNA em dispositivos microfluídicos que podem ser associados em &micro;TAS. Inicialmente, foi feito o desenvolvimento de um novo método de extração em fase sólida em que a eficiência de extração depende da manipulação magnética das partículas e não do fluxo da solução através da fase sólida. A utilidade desta técnica em isolar DNA puro de alta qualidade (amplificável) a partir de uma amostra biológica complexa foi demonstrada através da purificação de DNA a partir de sangue total e a subsequente amplificação do fragmento do gene &beta;-globina. A técnica descrita é rápida, simples e eficiente, permitindo uma recuperação de mais de 60% de DNA a partir de 600 nL de sangue em concentração suficiente para amplificação via reação em cadeia da polimerase (PCR). Após o desenvolvimento da extração dinâmica de DNA em fase sólida (dSPE) em microchip de vidro, o método foi adaptado para o uso em microchips de poliéster-toner (PT). Além da extração, a amplificação e separação de DNA também foram realizadas em microchips de PT. O processo convencional de fabricação dos dispositivos de PT produz canais com 12 &micro;m de profundidade. Este trabalho descreve um novo processo de fabricação dos microchips de PT com canais mais profundos. Uma cortadora a laser de CO2 é usada para definir a estrutura desejada no filme de poliéster recoberto com toner. Estes filmes de poliéster recobertos com toner e os canais recortados são utilizados com partes intermediárias no microchip. A tampa e a base (filmes de poliéster) são laminadas juntamente com as partes intermediárias. Desta forma microchips com canais mais profundos podem ser criados. Microchips com 4 filmes de poliéster (base, tampa, e dois filmes centrais) foram utilizados para realizar dSPE. Estes microchips possuem canais com ~270 &micro;m de profundidade. A dSPE adaptada para os microchips de PT demonstrou ser capaz de extrair eficientemente DNA (~65%), e o DNA purificado apresentou qualidade suficiente para PCR. A PCR realizada em microchips de PT demonstrou que os dispositivos de PT são compatíveis com os reagentes da PCR e o sucesso da reação de PCR foi demonstrado através da amplificação do fragmento de 520 pares de bases do &lambda;-DNA. A possibilidade de manipular diferentes soluções que são necessárias para realizar a extração e a PCR demonstra o grande potencial desta plataforma para realizar análises genéticas. Além da extração e amplificação, a separação também foi demonstrada nos dispositivos de PT. Duas integrações foram feitas nos microchips de PT, dSPE-PCR e PCR-separação. Na primeira integração a dSPE e PCR foram realizadas em uma única câmara, e a amplificação do fragmento de 520 pb do &lambda;-DNA foi demonstrada. Na segunda integração, o dispositivo foi fabricado com espessuras diferentes para os diferentes domínios. No domínio da PCR as câmaras possuem profundidade de ~270 &micro;m de profundidade, e para o domínio da eletroforese os canais apresentam 12 &micro;m de profundidade. A integração realizada sem válvulas foi demonstrada através da amplificação e detecção do fragmento de 520 pb do &lambda;-DNA em um mesmo microchip. Este trabalho demonstra o grande potencial dos microchips de PT para produzir dispositivos descartáveis totalmente integrados para análise genética. / Efforts to develop a microfluidic-based total analysis system (&micro;TAS) have been intense in the scientific community. The goal of achieving a device comprising DNA extraction, amplification, and detection in a single device, a true \"lab on a chip,\" is driven by the substantial advantages associated with such a device. This Thesis focus on development of methods for DNA analysis on microdevices, that can be associated with &micro;TAS. Sequentially, the first step was the development of a novel solid-phase extraction technique in which DNA is bound and eluted from magnetic silica beads in a manner that efficiency is dependent on the magnetic manipulation of the beads and not on the flow of solution through a packed bed. The utility of this technique in the isolation of reasonably pure, PCR-amplifiable DNA from complex samples is shown by isolating DNA from whole human blood, and subsequently amplifying a fragment of the &beta;-globin gene. The technique described here is rapid, simple, and efficient, allowing for recovery of more than 60% of DNA from 600 nL of blood at a concentration which is suitable for PCR amplification. The second step was the use of polyester-toner (PT) microchips for DNA analysis (extraction, PCR and separation). The laser-printing of toner onto polyester films has been shown to be effective for generating PT microfluidic devices with channel depths on the order of 12 &micro;m. We describe a novel and innovative process that allows for the production of multilayer PT microdevices with substantially larger channel depths. Utilizing a CO2 laser to create the microchannel in polyester sheets containing a uniform layer of printed toner, multilayer devices can easily be constructed by sandwiching the channel layer between uncoated cover sheets of polyester containing precut access holes. The process allows for the fabrication of channels several hundred microns in depth, with ~270 &micro;m deep microchannels utilized here to demonstrate the effectiveness of multilayer PT microchips for dynamic solid phase extraction (dSPE) and PCR amplification. Dynamic SPE adapted for PT microchip was able to recover more than 65% of DNA from 600 nL of blood and the DNA was compatible with downstream microchip-based PCR amplification. The compatibility of PT microchips was demonstrated by successful amplification of a 520 bp fragment of &lambda;-phage DNA. The ability to handle the diverse chemistries associated with DNA purtification and extraction is a testimony to potential utility of PT microchips beyond separations, and presents a promising new platform for genetic analysis that is low cost and easy to fabricate. Two integrations were carrying out on PT microchip, dSPE - PCR and PCR-ME. The first integration was made in a single chamber and the amplification of 520 bp fragment of &lambda;-phage was demonstrated. The second integration describes a process that allows the production of a multidomain microchip with different channel depths for the different domains for genetic analysis. The final device was made by the conventional sandwiching of the four polyester films of the PCR domain with the two polyester films for the electrophoresis domain. The successful valveless integration of PCR and separation was demonstrated by amplification and detection of a 520 bp fragment of &lambda;-phage DNA. This work shows the enormous potential of PT microchips to be used for total genetic analysis.
27

Value Added Services in India

Anandpadmanabhan, Narayanan January 2011 (has links)
Value Added Services (VASs) have become one of the major revenue generators in the telecom industry. Most of the telecom subscribers have started using VAS and it has become an important service for the customers. The objective of the project is to evaluate and analyse the need for value added services in India. The report begins with a discussion of existing VAS provided by 2G wide area cellular technologies and how these will change with the introduction of 3G technology. Following this the value chain of VAS is discussed. Next new trends, drivers, and challenges of the VAS are discussed in detail. The impact of content developers and software development on VAS are discussed. Then a method to analyse VAS is discussed, followed by method of analysing the ringback tones with respect to a company is provided followed by the method to analyse the importance of the content providers in the value chain. Then the Mobile commerce VAS is analysed in detail and ringback tone service provided by OnMobile Company is analysed in detail, followed by an analysis of the role of content providers in value chain. A survey on different services provided through VAS is taken among few of the VASs users in India and the results are included with graphs in the report. The thesis analysis results are very important in the modern telecommunication industry as VAS plays a major role in generating huge revenue and currently many industries are focusing on to provide mobile commerce services to its customers. The thesis answers various questions like, what are the different M-commerce services that are provided to the customers in the telecom industry. Why OnMobile Company provides different varieties of ringback tones to the user? Why the role of content providers is very important in the Value chain? The report concludes with conclusions explaining the different insights that are gained from the analysis of the VAS (M-Commerce), Ringback tones provided by OnMobile, role of content providers in the Value chain and the survey results. It is followed by the some suggestions and possible future work concerning Value Added Services in India. / Value Added Services (VASs) har blivit en av de största inkomst generatorerna i telekombranschen. De flesta av Telecom abonnenter har börjat använda VAS och det har blivit en viktigare service för kunderna. Målet med projektet är att utvärdera och analysera behovet av mervärdestjänster VAS i Indien. Rapporten inleds med en diskussion av befintliga VAS från 2G stort mobil teknik område och hur dessa kommer att förändras med införandet av 3G-tekniken. Efter detta kommer värdekedjan för VAS att diskuteras. De nästkommande nya trenderna, drivrutiner och utmaningar inom VAS diskuteras mer i detalj. Effekterna från innehållsutvecklare och mjukvaruutvecklingen inom VAS diskuteras också. Sedan kommer metoden för att analysera VAS att diskuteras, följt av en analys av ringsignaltjänsten med avseende på företag och en metod för att analysera betydelsen av innehållsutvecklare inom värdekedjan. Då mobil handel VAS analyseras i detalj och tillbaka ringningston tillhandahålls av OnMobile företag analyseras i detalj, följt av en analys av den roll som leverantörsrollen av innehåll i värdekedjan. En undersökning om olika tjänster som tillhandahålls via VAS tas bland några av de VASS användare i Indien och resultaten visas i grafer i rapporten. Avhandlingen analysresultaten är mycket viktiga i den moderna telekomindustrin som VAS spelar en viktig roll i att genererar stora inkomster och för närvarande många branscher fokuserar på att tillhandahålla mobil handel tjänster till sina kunder. Avhandlingen besvarar frågor som: Vilka är de olika mobila-handelstjänster som tillhandahålls inom telekomindustrin, varför OnMobile tillhandahåller olika typer av ringsignaltjänster till användaren? och Varför innehållsutvecklare är viktiga inom värdekedjan? Rapporten avslutas med slutsatser som förklarar de olika insikter som erhålls från analysen av VAS (M-Commerce), tillbaka ringningstoner från OnMobile, den roll som leverantörer av innehåll i värdekedjan och enkätresultat. Det följs av några förslag och möjliga framtida arbete om Value Added Services i Indien.
28

Svenska studenters uppfattningar av tonerna i kinesiska tvåstaviga ord

Hu, Guohua January 2015 (has links)
Studenter med ett icke-tonspråk som modersmål brukar ha svårigheter att lära sig de kinesiskatonerna när de börjar sina studier. Å ena sidan brukar kursböckerna på denna nivån användabara enstaviga ord och det har ansetts vara god pedagogik att läraren visar tonkonturerna medsina händer. Å andra sidan har forskningen om kinesiska länge varit koncentrerad på vilkavärden som grundtonen (F0) uppvisar i enstaviga ord. Det är många faktorer som tvärspråksforskningeninte har uppmärksammat, bl.a. det inflytande som konsonanterna har på F0 (vilketinfödda talare inte alltid är medvetna om).Det finns ingen samsyn när det gäller att förklara tonförväxlingsmönstren. Tidigare teorierinom ämnet andraspråksinlärning (Second Language Acquisition, SLA), som Perception AssimilationModel (PAM) och Speech Learning Model (SLM) har visat sig otillräckliga förstudiet av tonperception. På senare tid har PAM-Suprasegment försökt förklara hur den lärandesmodersmål antas närma sig kinesiskans tonsystem men modellen tar inte upp ordprosodin.Eftersom den moderna kinesiskans ordförråd till majoriteten består av tvåstaviga ord börforskningen lämna gamla spår för att finna andra kriterier – som duration och betoning – föratt förklara hur man lär sig höra kinesiskans toner, t.ex. vad som händer när två toner återfinnsi ett ord.Denna studie har som mål att ta reda på hur svenskar som studerar kinesiska som andraspråk/främmande språk uppfattar tonerna i kinesiska tvåstaviga ord. Experimentet bygger intepå tillrättalagda testord. Resultaten visar att tonerna först och främst påverkas av den initialakonsonanten och sedan av de omgivande tonerna. Vidare visas att det svenska systemet medaccent I och II i sin tur kan åstadkomma tonförväxlingar eftersom kinesiska tvåstaviga orddelvis uppvisar samma mönster.Resultaten illustrerar att tonidentifiering är en dynamisk och komplex process. Det krävsfortsatt forskning om tonerna för att få grepp om dem men det kan inte stanna där: interaktionenmellan ljud och ordprosodi behöver belysas bättre för att uppnå god behärskning avprosodin i språkundervisningen. / Foreign adult students with atonal language usually have, in the beginning of their Chinesestudy, difficulties to identify the Chinese tones. On one side, only monosyllabic tones arementioned in course books during this earlier stage and to illustrate the tone contours withhands has been treated as an effective pedagogy. On the other side, research on Chinese hasfor long been solely concentrated upon the values of the fundamental frequency (F0) of thevowels in monosyllabic words. In cross-linguistic studies many factors, among others the effectsof consonants on F0 that native speakers are not aware of, have still not been paidspecial attention to.There is no consensus regarding the explanation to tone confusion patterns. Earlier theoriesof Second Language Acquisition (SLA) like Perception Assimilation Model (PAM) andSpeech Learning Model (SLM) are no longer suited for tone perception. Recently, PAMSuprasegmenthas tried to approach that the intonation of the learners’ native language is assumedto be assimilated to the Chinese tone system. However, this model ignores the wordprosody. Nowadays, when the modern Chinese vocabulary consists of a majority of disyllabicwords, research has to be re-directed to find other criteria e.g. temporal and stress for explainingthe complexity of Chinese tone perception, i.e. how two tones behave when they arecombined in one word.The purpose of this essay is to explore how native Swedish speakers learning Chinese assecond/foreign language perceive the Chinese tones of disyllabic words. The experiment isnot based on elaborated test words. The results show that tones are first of all affected by theinitial consonants and sequentially influenced by the surrounding tones with accordance toChinese. It further reveals that Swedish accent I/II patterns might be a reasonable explanationfor the Chinese tone confusion patterns since partially acoustic properties of Chinese disyllabicwords overlap the Swedish accents.These results mean that tone perception is a dynamic and complex process. Further researchon tone perception should explore profoundly and widen interaction between sounds andword prosody, which paves the way for more effective prosodic practice in language education.
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Att lyssna till meningen i mellanrummet : En läsning av Jean-Luc Nancys Listening ur Jacques Derridas différance i klangen av musikens blå toner / Listening to the meaning in the space between : A reading of Jean-Luc Nancy’s Listening through Jacques Derridas différance in the sonority of the blue notes

Ulriksson, Tanja January 2020 (has links)
This essay attempts to listen to meaning in the borderland, and asks in between which faculties and senses, through which we see and/or listen to the world, do we seek sense? My writing is located on this border, or more precisely on the erased border that I call an interspace or an interval, the place where we look for sense in the relation between language, philosophy, politics, and music. I have done this through the reading of three contemporary philosophers: Jacques Derrida, Jean-Luc Nancy, and Angela Davis. Derrida and Nancy have provided me with a theoretical and philosophical background for my approach to Davis’s philosophic and political claims. My analysis sets out from Derrida’s différance and what it reveals in the sign system of language. This is continued through a discussion of Nancy’s question: Is philosophy capable of listening, in all senses of the word? Is the philosopher not someone who always hears? In my reading, this connection is established through the blue notes. Davis, finally, provides me with a support for my claim that we, in the political significance of blues, in the traces of meaning that it contains, might be able to listen to Derrida’s différance. Keywords: Listening, meaning, différance, blues, sonority, blue notes, in between, border, subject, Jacques Derrida, Angela Y Davis, Jean-Luc Nancy. / Denna uppsats syftar till att försöka lyssna till meningen i gränslandet – mellan vilka relationer i våra förmågor och sinnen, av att se och/eller lyssna till världen, söker vi mening? Jag vill skriva om den gränsen, eller mer kanske den utsuddade gränsen i platsen jag kallar mellansfär och mellanrum, som den plats där vi söker mening i relationen mellan språk, filosofi, politik och musik. När vi idag söker mening och talar om varat, om individen och subjektivitet, kan det vara så att vi inte längre kan göra det genom fasta tecken, system och former? Istället för att stanna kvar i ett tillstånd av upprepande och separerande som landar i uteslutande och förtryck, i värdeskalor och normer, istället för att endast höra klassiska notsystem, eller förstå språkliga regler hos fasta teckensystem; kan det vara så att vi idag får vända oss till lyssnandet och mellansfären i de blå tonernas différance för att förstå olika individer och subjektivitet i relation till världen? Genom att göra en analys av Derridas term différance i hans text med samma namn: ”Différance” ur boken Margins of philosophy, ska jag försöka närma mig Nancys bok Listening samt läsa hans text genom tanken på différance i Nancys teori och förståelse om lyssnandet.  För att undersöka hur lyssnande och musik kan få ett praktiskt uttryck, av de teoretiska meningarna vi söker i différance, vill jag använda musikgenrerna blues och jazz och de blå toner som bluesen förhåller sig i och mellan. Min teori är att bluesen kan ge en plats (av flera) för var skillnader möts mellan text, värld och musik; platsen där différance kan lyssnas till, synliggöras och hörs. I den teorin vänder jag mig till Angela Davis bok Blues Legacies and Black Feminism som stöd för bluesens utveckling. Det jag ämnar närma mig hos Davis är just bluesens meningssökande och plats i samhället
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Development of a Cost-Effective, Reliable and Versatile Monitoring System for Solar Power Installations in Developing Countries : A Minor Field Study as a Master Thesis of the Master Programme in Engineering Physics, Electrical Engineering

Trella, Fredrik, Paakkonen, Nils January 2016 (has links)
This report is the result of a conducted Minor Field Study (MFS), to the greatestextent funded by the Swedish International Development Cooperation Agency(SIDA), in an attempt to design a system for evaluating smaller solar power systems indeveloping countries. The study was to the greater part conducted in Nairobi, Kenyain close collaboration with the University of Nairobi. The aim was to develop asystem that would use easily available components and keep the costs to a minimum,yet deliver adequate performance. The system would measure certain parameters of asolar power system and also relevant environmental data in order to evaluate theperformance of the system. Due to the specific competence of the collaboratinggroup at the University of Nairobi, a Kinetis Freescale K64-microcontroller with anARM-Cortex processor was selected as the core of the design. Components wereselected, schematics were drawn, a circuit board was designed and manufactured andsoftware was written. After 12 weeks a somewhat satisfying proof-of-concept wasreached at the end of the field study in Kenya. The project however proved howdifficult it is to go from first idea to a functional proof-of-concept during a limitedtimeframe, and also in an East-African country. The final proof-of-concept was testedat Mpala Research Centre in Kenya and despite containing some flaws proved that itwould indeed be possible to design a working system on the principles discussed inthis report. The system is open-source, so anyone may use and modify it.

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