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Thancanamootoo, Aganaden. "A study of unsteady annular downflow in building drainage vertical stacks." Thesis, Heriot-Watt University, 1989. http://hdl.handle.net/10399/1037.
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Ng, Ricky Ming Yin. "Vertically stacked silicon nanowire : fabrication and characterization /." View abstract or full-text, 2008. http://library.ust.hk/cgi/db/thesis.pl?ECED%202008%20NG.
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Neumann, Dorothea, and Mattias Asplund. "Utrymning uppåt : Påverkan av vinterkläder vid utrymning uppåt via trappor." Thesis, Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-33015.
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When cities grow larger the demand for more residential buildings and public transport increases. To be able to meet the demands and still make the city compact the interest for underground facilities grows. Underground facilities come with some drawbacks, one example is the evacuation where the people are expected to evacuate upwards. This master thesis is aiming to further develop the research done on the subject by examining the impact of winter clothing. Two tests were performed in Skrapan, which is 25 floors high. The participants went up for 22 of the floors and were recorded during the ascending. Some of the participants had a pulse watch and a breathing mask, which measured the oxygen consumption. The median for the walking speed varied between 0,81 m/s and 0,56 m/s with regular clothing and 0,78 m/s to 0,57 m/s with winter clothes. In the building codes it says that 0,6 m/s should be used when calculating evacuation times when ascending stairs. The heart rate did not change significantly between the two tests. However, the oxygen consumption was higher with the jacket on. The participants would not have been able to keep going for much longer than 5 minutes with their current pace. According to the results in this master thesis 0,6 m/s is too high because in the tests that were made the participants were physically active and still couldn’t keep that speed up for the whole test. Due to the test being two days in a row, almost all of the participants walked slower the second time. However, the ones that walked with winter clothes the second day walked more slowly than the ones with regular clothes compared to the first day. Therefore, it is safe to say that the clothes do affect the walking speed of evacuating people and that more clothes i.e. warm shoes or a hat will have an even greater impact.I takt med att städerna växer, både till yta och befolkningsmängd, ökar behovet av infrastruktur bland annat inom kollektivtrafiken och transportvägar. Genom att bygga dessa anläggningar under marken går det att exploatera marken ovan till andra ändamål. Med undermarksanläggningar kommer vissa svårigheter, så som begränsade utrymningsmöjligheter. Riktlinjerna för utrymning uppåt är inte till för längre trappor, och är därför inte representativt för de nya användningsområdena. Vikten av att dimensionera utrymningsmöjligheterna utifrån vad dagens befolkning kan prestera är relevant för att säkerställa en trygg utrymning i händelse av en olycka. Examensarbetet inriktar sig därför på att vidareutveckla tidigare forskning om utrymning uppåt genom att undersöka hur gånghastigheterna i trappor påverkas av vinterkläder. Försök genomfördes med 21 personer under två dagar i ett av Skrapans utrymningstrapphus, där varje försöksperson fick gå en gång per dag. Mätmetoderna som användes var bland annat; pulsklocka, tidtagning, videoobservationer och andningsmask som mäter syreupptagningsförmågan. Medianen för gånghastigheten beräknades på varje våningsplan där de högsta värdet med vanliga kläder blev 0,81 m/s, 3 meter upp i trappan och det lägsta 0,56 m/s, 57 meter upp i trappan. Med vinterkläder blev motsvarande värden 0,78 m/s, 5 meter upp i trappan och 0,57 m/s, 33 meter upp i trappan. Enligt Boverkets allmänna råd om analytisk dimensionering ska den dimensionerande gånghastigheten i trappor sättas till 0,6 m/s. Denna riktlinje är inte godtagbar eftersom försökets urvalsgrupp hade svårt att hålla den hastigheten trots att majoriteten av försökspersonerna i examensarbetet var unga och i god kondition. Gånghastigheterna påverkades även av att försökstillfällena genomfördes dagarna efter varandra vilket gjorde att försökspersonerna inte hade möjlighet att återhämta sig helt mellan försöken. Dock var tidsskillnaden från första dagen till den andra större för de som gick med vinterkläder andra dagen än för de som gick med vanliga kläder andra dagen. Vilket visar på att försökspersonerna blivit påverkade av vinterkläderna och därför gått långsammare. Mätningarna av syreupptagningsförmågan hos försökspersonerna gav varierande resultat, mycket beroende på kön och om de hade vinterkläder på sig eller inte. Kvinnornas utnyttjande grad ökade från 70-85 % till 73-90 % av sin maximala syreförbrukning när de var iklädda vinterkläder. Jämfört med männens utnyttjande grad som sjönk från 63-85 % till 61-77 % vid användandet av vinterkläder. Försökspersonerna var nära sin maximala syreförbrukning, VO2,max, vilket tyder på att de inte skulle klara av att hålla samma tempo i en längre trappa. Männen skulle kunna hålla samma tempo i cirka 15 minuter medan kvinnorna som ligger på 90 % av sin kapacitet enbart skulle kunna hålla samma hastighet i cirka 5 minuter. Vilket är ett ytterligare tecken på att hastigheten i BBRAD är för hög i långa trappor.
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Hon, Chi Kwong. "3D packaging of multi-stacked flip chips with plugged through silicon vias for vertical interconnection /." View abstract or full-text, 2006. http://library.ust.hk/cgi/db/thesis.pl?MECH%202006%20HON.
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Harrison, Andrew J. "The development and application of biomechanical analysis techniques for evaluation of developmental stages in vertical jump." Thesis, University of Salford, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.265526.
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Tavares, Marcelo Botini [UNESP]. "Utilização de colunas verticais de filtração em manta e areia como pré-tratamento de filtro lento." Universidade Estadual Paulista (UNESP), 2008. http://hdl.handle.net/11449/98081.
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A Filtração Lenta é um processo de tratamento de água que tem como principal característica a eficiente remoção de patógenos, algas e cianobactérias, as quais nos últimos anos têm-se desenvolvido muito nos reservatórios de abastecimento de água devido à eutrofização causada principalmente pelas atividades antrópicas. As cianobactérias produzem substâncias tóxicas conhecidas como cianotoxinas, que causam problemas gástricos, dermatológicos e toxicológicos nos humanos, além de problemas nas estações de tratamento de água. Apesar da eficiência da Filtração Lenta na remoção destes organismos, ela possui restrições quanto à área necessária aos filtros lentos, quanto ao processo de limpeza destes e dos pré-filtros de pedregulho quando utilizados no tratamento. Esta pesquisa teve então como objetivo desenvolver uma pré-filtração ao filtro lento, através das Colunas Verticais de Pré-Filtração, que fosse eficiente na remoção de parâmetros físico-químicos e bacteriológicos e também no procedimento de limpeza, tornando-o mais rápido e menos dispendioso. Este trabalho foi vinculado ao Programa de Pesquisa em Saneamento Básico (PROSAB) de número 5 do ano de 2007. Para tanto, foi utilizada uma instalação piloto de tratamento de água existente na cidade de Ilha Solteira/SP na qual o processo de tratamento foi o de Filtração em Múltiplas Etapas. Nela foram introduzidas quatro colunas verticais de pré-filtração com taxas diferentes entre si. Foram analisados parâmetros de qualidade de água, o período de desenvolvimento da camada biológica e o tempo de colmatação das unidades filtrantes. Como alguns resultados da pesquisa, foram notificados: a rapidez e facilidade no procedimento de limpeza das colunas, além de necessitarem de limpezas menos freqüentes que os pré-filtros de pedregulho; remoção de cerca de 95% de algas...
Slow filtration is a water treatment process that provides an efficient removal of pathogens, algae and cyanobacteria, which in recent years have been developed in a large amount in water reservoirs due to eutrophication, caused by human habits. The cyanobacteria produces toxic substances known as cyanotoxins, which cause gastric, skin and toxic disorders in humans, as well as problems in water treatment plants. Despite the efficiency of slow sand filtration in removing these bodies, it has restrictions on the required area for slow filters, on their cleaning process or rubble pre-filters cleaning when used in treatment. The objective of this research is developing a pre-filter to filter slowly through vertical columns pre-filtration, which would be efficient in the removal of physical, chemical and bacteriological bodies and also in cleaning process, making it faster and less expensive. This work was linked to the Programa de Pesquisa em Saneamento Básico (PROSAB) of 5th paragraph from the year of 2007. For this, we used an existing pilot plant for water treatment from of Ilha Solteira City - SP in which the process of treatment was Multiple Stages Filtration. Four pre-filtration vertical columns with different rates were introduced. We analyzed parameters of water quality, the period of organic layer development and the filter units clogging time. As some search results have been reported: the speed and ease of the columns cleaning procedure, less requiring of rubble pre-filters frequent cleaning; approximately 95% of algae and cyanobacteria removal by the columns; satisfactory turbidity removal, apparent color and true color, and smaller area required for its installation, because of their vertical shape.
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Bhatnagar, Sameer. "Fabrication of a vertically stacked grating coupler for optical waveguides in silicon-on-insulator." Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=116025.
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Couplers that can couple light vertically between stacked waveguides are finding importance in the push towards higher density and lower cost optoelectronics. A compact grating coupler (12.8mum) designed by a former student is implemented in this project. The device is patterned by reactive-ion-etch into silicon-on-insulator with a 250 nm thick device layer, ensuring single mode operation. Alignment marks are patterned into the backside so that aligned bonding can be carried out. A die bonding recipe is developed using an intermediate adhesive film of SU-8-2. A novel approach to creating optically smooth input facets is included in the final steps of the process. Optical testing remains to be done.
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Wisch, Lucas Nataniel. "FLUTUAÇÃO POPULACIONAL DOS PRINCIPAIS NOCTUÍDEOS E DISTRIBUIÇÃO VERTICAL DE OVOS E LARVAS NA CULTURA DA SOJA." UNIVERSIDADE ESTADUAL DE PONTA GROSSA, 2011. http://tede2.uepg.br/jspui/handle/prefix/2215.
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Previous issue date: 2011-10-31Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Soybean is one of the main oleaginous crop produced in Brazil. Studies on populational dynamic and immature stage vertical distribution in soybean canopy are very important to improve technology application and control timing. We studied population dynamics and vertical distribution of eggs and larvae of the velvetbean caterpillar, Anticarsia gemmatalis and two Plusiinae species, during the cycle of two soybean cultivars of different growth habits in three sowing dates. Experiments were conducted on Coodetec 206 and BMX Potência RR cultivars during the 2010/2011 growing season in Ponta Grossa, Paraná state. Samples were collected through the crop cycle. Eggs and caterpillars from each third of the plant (bottom, middle and upper) and on different plant structures (main stem, branches, pods and adaxial or abaxial surfaces of leaves) were quantified. Data were analyzed using descriptive statistics and nonparametric Kruskal-Wallis analysis. Plusiinae species occurred simultaneously with A. gemmatalis, which was the predominant species. Highest densities of eggs and larvae of A. gemmatalis were recorded during the second half of January and February. In February we observed the highest densities of Plusiinae. Through the late sowing season we recorded the highest densities of immature stages of Noctuidae. The highest eggs densities for A. gemmatalis and Plusiinae occurred in the middle third (44.03% and 45.99%, respectively) of the canopy followed by the lower (31.96% and 34.18%) and upper portion (24.01% e 19.83%). Small larvae of A. gemmatalis were found mainly in middle (44.08%) and lower third of the plant (36.97%), while medium larvae occurred in higher density in the middle (42.86%) and upper (41.90%) stratum. Meanwhile, most of the large larvae are found in the upper portion of the canopy (63.41%). Highest densities of small, medium and large Plusiinae larvae, we found in middle (43.37%, 44.63% e 44.83%, respectively) and lower (49.46%, 31.40% e 31.03%) third of the canopy. Eggs and caterpillars were found mainly on the abaxial surface of leaflets.
A soja é uma das principais oleaginosas cultivadas no Brasil. Os estudos sobre a ocorrência dos estádios imaturos de Noctuídeos e sua distribuição espacial no perfil da planta são de grande importância para definir o momento de controle e aprimorar a tecnologia de aplicação. O objetivo deste trabalho foi avaliar a flutuação populacional e a distribuição vertical de ovos e larvas dos principais Noctuídeos, Anticarsia gemmatalis e Plusiinae, durante o ciclo de duas cultivares de soja de diferentes hábitos de crescimento em três épocas de semeadura. Os experimentos foram conduzidos durante a safra 2010/2011 no município de Ponta Grossa – PR, em três épocas diferentes de semeadura das cultivares Coodetec 206 e BMX Potência RR. As amostragens foram realizadas durante todo o ciclo da cultura em diferentes alturas da planta (terço superior, médio e inferior) e em diferentes estruturas da planta (haste principal, ramos, vagens e face adaxial ou abaxial das folhas). Os dados foram analisados através da estatística descritiva e do teste não-paramétrico de Kruskal-Wallis. As espécies de Plusiinae ocorreram simultaneamente a A. gemmatalis, a qual foi a espécie predominante. As maiores densidades de ovos e lagartas de A. gemmatalis foram registradas na segunda quinzena de janeiro e durante o mês de fevereiro, mês em que se observou maior densidade de Plusiinae. As semeaduras mais tardias apresentaram as maiores densidades de estádios imaturos de Noctuídeos. A maior oviposição, tanto para A. gemmatalis quanto a Plusiinae ocorreu no terço médio (44,03% e 45,99%, respectivamente) seguido pelo inferior (31,96% e 34,18%) e superior (24,01% e 19,83%). As lagartas pequenas de A. gemmatalis foram encontradas principalmente nos terços médio (44,08%) e inferior (36,97%), enquanto as lagartas médias ocorreram em maior densidade nos estratos médio (42,86%) e superior (41,90%) e os indivíduos grandes, na região apical (63,41%) do dossel. A maior densidade de lagartas de Plusiinae pequenas, médias e grandes foi observada no terço médio (43,37%, 44,63% e 44,83%, respectivamente) e inferior (49,46%, 31,40% e 31,03%). Os ovos e as lagartas dos Noctuídeos foram encontrados, principalmente, na face abaxial dos folíolos.
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Steht, Markus von. "Imaging of vertical seismic profiling data using the common-reflection-surface stack Abbildungsverfahren für seismische Daten aus Bohrlochmessungen mit der Common-Reflection-Surface Stapelung /." [S.l. : s.n.], 2008. http://digbib.ubka.uni-karlsruhe.de/volltexte/1000007747.
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Tavares, Marcelo Botini. "Utilização de colunas verticais de filtração em manta e areia como pré-tratamento de filtro lento /." Ilha Solteira : [s.n.], 2008. http://hdl.handle.net/11449/98081.
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Orientador: Edson Pereira TangerinoBanca: Tsunao Matsumoto
Banca: Luiz Di Bernardo
Resumo: A Filtração Lenta é um processo de tratamento de água que tem como principal característica a eficiente remoção de patógenos, algas e cianobactérias, as quais nos últimos anos têm-se desenvolvido muito nos reservatórios de abastecimento de água devido à eutrofização causada principalmente pelas atividades antrópicas. As cianobactérias produzem substâncias tóxicas conhecidas como cianotoxinas, que causam problemas gástricos, dermatológicos e toxicológicos nos humanos, além de problemas nas estações de tratamento de água. Apesar da eficiência da Filtração Lenta na remoção destes organismos, ela possui restrições quanto à área necessária aos filtros lentos, quanto ao processo de limpeza destes e dos pré-filtros de pedregulho quando utilizados no tratamento. Esta pesquisa teve então como objetivo desenvolver uma pré-filtração ao filtro lento, através das Colunas Verticais de Pré-Filtração, que fosse eficiente na remoção de parâmetros físico-químicos e bacteriológicos e também no procedimento de limpeza, tornando-o mais rápido e menos dispendioso. Este trabalho foi vinculado ao Programa de Pesquisa em Saneamento Básico (PROSAB) de número 5 do ano de 2007. Para tanto, foi utilizada uma instalação piloto de tratamento de água existente na cidade de Ilha Solteira/SP na qual o processo de tratamento foi o de Filtração em Múltiplas Etapas. Nela foram introduzidas quatro colunas verticais de pré-filtração com taxas diferentes entre si. Foram analisados parâmetros de qualidade de água, o período de desenvolvimento da camada biológica e o tempo de colmatação das unidades filtrantes. Como alguns resultados da pesquisa, foram notificados: a rapidez e facilidade no procedimento de limpeza das colunas, além de necessitarem de limpezas menos freqüentes que os pré-filtros de pedregulho; remoção de cerca de 95% de algas... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Slow filtration is a water treatment process that provides an efficient removal of pathogens, algae and cyanobacteria, which in recent years have been developed in a large amount in water reservoirs due to eutrophication, caused by human habits. The cyanobacteria produces toxic substances known as cyanotoxins, which cause gastric, skin and toxic disorders in humans, as well as problems in water treatment plants. Despite the efficiency of slow sand filtration in removing these bodies, it has restrictions on the required area for slow filters, on their cleaning process or rubble pre-filters cleaning when used in treatment. The objective of this research is developing a pre-filter to filter slowly through vertical columns pre-filtration, which would be efficient in the removal of physical, chemical and bacteriological bodies and also in cleaning process, making it faster and less expensive. This work was linked to the Programa de Pesquisa em Saneamento Básico (PROSAB) of 5th paragraph from the year of 2007. For this, we used an existing pilot plant for water treatment from of Ilha Solteira City - SP in which the process of treatment was Multiple Stages Filtration. Four pre-filtration vertical columns with different rates were introduced. We analyzed parameters of water quality, the period of organic layer development and the filter units clogging time. As some search results have been reported: the speed and ease of the columns cleaning procedure, less requiring of rubble pre-filters frequent cleaning; approximately 95% of algae and cyanobacteria removal by the columns; satisfactory turbidity removal, apparent color and true color, and smaller area required for its installation, because of their vertical shape.
Mestre
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Kalusniak, Sascha. "Ultraviolet and visible semiconductor lasers based on ZnO heterostructures." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2014. http://dx.doi.org/10.18452/16898.
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Im Rahmen dieser Arbeit wurden die optischen Eigenschaften von auf ZnO-basierenden Heterostrukturen untersucht. Besonderes Augenmerk lag hierbei auf ihrer Eignung als aktives Material in Laserdioden für den ultravioletten und sichtbaren Spektralbereich. Es wurde gezeigt, dass ZnO und seine ternären Mischkristalle ZnCdO und ZnMgO erstaunlich vielfältige Anwendungen ermöglichen. Mit diesem Materialsystem lässt sich sowohl ein sehr großer Spektralbereich für Lasertätigkeit abdecken als auch eine Vielzahl von Laseranordnungen realisieren. Im Detail wurde demonstriert, dass sich die Lasertätigkeit von ZnCdO/ZnO Quantengraben-Strukturen vom violetten bis in den grünen Spektralbereich verschieben lässt. Obwohl diese Strukturen starke interne elektrische Felder aufweisen, konnte optisch gepumpte Lasertätigkeit bei Zimmertemperatur bis zu einer Wellenlänge von 510 nm gezeigt werden. Die für die Lasertätigkeit nötige optische Rückkopplung wird durch makroskopische Defekte der Probe verursacht und die Proben fungieren somit als Zufallslaser. Die Herstellung von Mikroresonatoren ermöglichte die Untersuchung des Zusammenspiels von Fabry-Perot- und Zufalls-Rückkopplung. Die experimentellen und theoretischen Ergebnisse zeigen, dass der Schwellengewinn eines Zufallslasers in der Regel größer ist als der des Fabry-Perot-Lasers. Des Weiteren wurde gezeigt, dass hoch reflektierende Braggreflektoren für den ultravioletten und blau/grünen Spektralbereich aus ZnO- und ZnMgO-Schichten hergestellt werden können. Ferner wurden die teils unbekannten Brechungsindexverläufe der verwendeten ternären Materialen erarbeitet und Mikrokavitäten mit ZnO/ZnMgO Quantengraben Strukturen als aktive Schichten realisiert. An diesen Kavitäten konnte bei Temperaturen bis zu 150 K starke Kopplung zwischen Exzitonen und Photonen nachgewiesen werden. Bei Zimmertemperatur konnte vertikal-emittierende Lasertätigkeit im nahen ultravioletten Spektralbereich demonstriert werden.In the framework of this thesis, the optical properties of ZnO-based heterostructures fabricated by molecular beam epitaxy have been investigated, particularly with regard to their suitability for semiconductor laser devices operating in the ultraviolet and visible spectral range. It turned out that ZnO and its ternary alloys ZnMgO and ZnCdO are extremely versatile. They allow to tune the laser emission in a wide spectral range as well as to realize various laser geometries. In detail, it was shown that the laser emission of ZnCdO/ZnO multiple quantum wells can cover a spectral range from violet to green wavelengths. Although these structures suffer from large built-in electric fields, room temperature laser action under optical pumping was demonstrated up to a wavelength of 510. The optical feedback for lasing is provided by growth imperfections on a macroscopic length scale turning these structures into random lasers. The fabrication of micro-resonators allowed to study the interplay between random and Fabry-Perot feedback. The experimental and theoretical analysis shows that random feedback generally requires a larger gain than under Fabry-Perot feedback. Further, this work demonstrates that ZnO- and ZnMgO-layers can be used to fabricate highly reflective distributed Bragg reflectors for applications in the ultraviolet and blue/green spectral range. The partly unknown dispersion curves of the index of refraction of the employed ternary alloys have been elaborated. This enabled the realization of all monolithic microcavities with ZnO/ZnMgO quantum wells as active zone. For temperatures below 150 K strong exciton-photon coupling is observed in such microcavities. At room temperature, vertical cavity surface emitting laser action in the near UV spectral range is demonstrated for appropriately designed microcavities.
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Roleda, Michael Y. "Effects of ultraviolet radiation on early life stages of cold temperate and Arctic macroalgae : implications for recruitment and vertical depth distribution = Effekte von UV-Strahlung auf frühe Lebensstadien kaltgemässiger und arktischer Makroalgen : Auswirkungen auf Rekrutierung und Vertikalverteilung /." Bremerhaven : Alfred-Wegener-Institut für Polar- und Meeresforschung, 2006. http://www.loc.gov/catdir/toc/fy0703/2006499119.html.
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Garduno, Nolasco Edson. "Nano-scale approaches for the development and optimization of state-of-the-art semiconductor photovoltaic devices." Thesis, University of Manchester, 2014. https://www.research.manchester.ac.uk/portal/en/theses/nanoscale-approaches-for-the-development-and-optimization-of-stateoftheart-semiconductor-photovoltaic-devices(927e70db-03ff-43e0-8b27-5472bc4a293f).html.
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This project is concerned with both the study of different Multiple Quantum Wells (MQWs) structures using the In0.53Ga0.47As/In0.52Al0.48As material system lattice matched to InP and a systematic investigation of the properties of InAs QD systems within GaAs with the aim of achieving enhancements of solar cell performance. The key challenge is the growth of QDs solar cell structures which exhibit sufficient absorption (enhanced infrared absorption) to increase short circuit current density (Jsc) but which can still maintains a high open circuit voltage (Voc). The research consists of epitaxial growth using state-of–the-art MBE, optical absorption, photoluminescence and high resolution x-ray diffraction measurements as well as device fabrication and characterization of novel solar cell structures. Optimization was performed on these novel cells to further improve their efficiency by inserting stacks of QD into different regions of the device. The effect of localized doping of such structures was used in an attempt to maintain and enhance the open-circuit voltage which in turn increases the device efficiency. The fabricated devices were characterized using measurements of the dark/light current-voltage (I-V) characteristics and spectral response (50-480 K). Solar cell external quantum efficiencies under standard air mass (AM) 1.5 spectrum were determined and the suitability of these new cells under solar concentration were assessed. Full physical simulations are performed using SILVACO semiconductors modelling software to generate models of multi-junction solar cells that were crucial in informing iterations to growth and fabrication and help to reconcile theory with experiment. One of the key findings, of this thesis, is the fact that Intermediate band photovoltaic devices using material based on InAs/GaAs vertically stacked quantum dot arrays, can be used in applications according to specific configuration criteria such as high temperature operation conditions. The intermediate band cell, including an inter-dot doped configuration, has been found to be a potential candidate as the inter dot doping profile reduces the efficiency degradation below the GaAs values including an enhancement in the open circuit voltage. It has been proved that these devices not only have a good performance at high temperatures but also by changing the vertical stacking QD layer periodicity can enhance the short circuit current density while keeping a large open circuit voltage. It was confirmed in practical device operation that thermal energy is required to enable the intermediate band in InAs/GaAs QD materials. The impact of this works can help in the future improvements of the intermediate band solar cells based on InAs on GaAs QD. The best overall efficiency of 11.6 % obtained in this work is an excellent value for so simple devices configuration. The Si3N4, tested for the first time on InAs/GaAs QD materials, reduces the reflectance on the device surface to a value of 2% and the operational wavelength can be tuned by controlling the layer thickness. A 100 nm Si3N4 antireflective coating proved to be an excellent coating from 700 to 1000 nm. In terms of short circuit current density a 37% enhancement was achieved.
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Bocková, Lenka. "Měření svislých posunů kostela v Zábrdovicích." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2014. http://www.nusl.cz/ntk/nusl-227126.
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The diploma thesis deals with measuring height new stage of the church network in Brno Zabrdovice. Measuring by using method of precise leveling be going on with previous stage began in 2002, in order to detect vertical displacement. Processing include calculation and adjust of the heights, compare with fundamental and previous stage, interpretation and graphical form of vertical displacement. The thesis includes measuring and processing angular deflection of church towers.
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Hawatmeh, Derar Fayez. "Three Dimensional Direct Print Additively Manufactured High-Q Microwave Filters and Embedded Antennas." Scholar Commons, 2018. http://scholarcommons.usf.edu/etd/7165.
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The need for miniaturized, and high performance microwave devices has focused significant attention onto new fabrication technologies that can simultaneously achieve high performance and low manufacturing complexity. Additive manufacturing (AM) has proven its capability in fabricating high performance, compact and light weight microwave circuits and antennas, as well as the ability to achieve designs that are complicated to fabricate using other manufacturing approaches. Direct print additive manufacturing (DPAM) is an emerging AM process that combines the fused deposition modeling (FDM) of thermoplastics with micro-dispensing of conductive and insulating pastes. DPAM has the potential to jointly combine high performance and low manufacturing complexity, along with the possibility of real-time tuning.
This dissertation aims to leverage the powerful capabilities of DPAM to come-up with new designs and solutions that meet the requirements of rapidly evolving wireless systems and applications. Furthermore, the work in this dissertation provides new techniques and approaches to alleviate the drawbacks and limitations of DPAM fabrication technology. Firstly, the development of 3D packaged antenna, and antenna array are presented along with an analysis of the inherent roughness of 3D printed structures to provide a deeper understanding of the antenna RF performance. The single element presents a new volumetric approach to realizing a 3D half-wave dipole in a packaged format, where it provides the ability to keep a signal distribution network in close proximity to the ground plane, facilitating the implementation of ground connections (e.g. for an active device), mitigating potential surface wave losses, as well as achieving a modest (10.6%) length reduction. In addition, a new approach of implementing conformal antennas using DPAM is presented by printing thin and flexible substrate that can be adhered to 3D structures to facilitate the fabrication and reduce the surface roughness. The array design leverages direct digital manufacturing (DDM) technology to realize a shaped substrate structure that is used to control the array beamwidth. The non-planar substrate allows the element spacing to be changed without affecting the length of the feed network or the distance to the underlying ground plane.
The second part describes the first high-Q capacitively-loaded cavity resonator and filter that is compatible with direct print additive manufacturing. The presented design is a compromise between quality factor, cost and manufacturing complexity and to the best of our knowledge is the highest Q-factor resonator demonstrated to date using DPAM compatible materials and processes. The final version of the single resonator achieves a measured unloaded quality factor of 200-325 over the frequency range from 2.0 to 6.5 GHz. The two pole filter is designed using a coupled-resonator approach to operate at 2.44 GHz with 1.9% fractional bandwidth. The presented design approach simplifies evanescent-mode filter fabrication, eliminating the need for micromachining and vias, and achieving a total weight of 1.97 g. The design is fabricated to provide a proof-of-principle for the high-Q resonator and filter that compromises between performance, cost, size, and complexity. A stacked version of the two-pole filter is presented to provide a novel design for multi-layer embedded applications.
The fabrication is performed using an nScrypt Tabletop 3Dn printer. Acrylonitrile Butadiene Styrene (ABS) (relative permittivity of 2.7 and loss tangent of 0.008) is deposited using fused deposition modeling to form the antenna, array, resonator, and filter structures, and Dupont CB028 silver paste is used to form the conductive traces conductive regions (the paste is dried at 90 °C for 60 minutes, achieving a bulk DC conductivity of 1.5×106 S/m.). A 1064 nm pulsed picosecond Nd:YAG laser is used to laser machine the resonator and filter input and output feedlines.
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Kozůbková, Lenka. "Bytový dům ve svahu, Uherský Brod." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2013. http://www.nusl.cz/ntk/nusl-226179.
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This is a complex of two apartment terraced buildings with the mirror disposition in Uherský Brod. Whole object is detached and it is set into the hillside. The object has three floors and one underground floor and it is covered with a shed roof. Two entrances lead into the each apartment building. The first entrance is in the second floor and the second entrance is in the third floor. The entry to the object is from the northeastern side, from the street named Babí louka. The object has a vertical brick construction system and it has concrete floors and interior stairs. The outer walls are insulated with a mineral insulation.
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Charvát, Lukáš. "Oceňování ocelových konstrukcí." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2013. http://www.nusl.cz/ntk/nusl-226121.
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This diploma thesis mainly deals with valuation of steel structures from the perspective of an investor. Today there are several types of steel constructions, which assemble is partly done in workshop, so called “bridge-workshop”, and the rest of the assembling is done directly at the building site. That is the main difference from the construction industry. This fact makes financial valuation of whole thesis very difficult, because construction companies often do not state detailed breakdown of their activities. The main goal of this thesis is to suggest procedure how to value steel constructions in a phase of documentation processing, workshop production, transportation and technological equipment construction at the site.
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Volf, Josef. "Sportcentrum Broumov." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2014. http://www.nusl.cz/ntk/nusl-226590.
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The topic of the masters thesis is newly built sports center in Broumov on the outskirts of the historic center. The proposal was placed high demands on appearance. There is a non-traditional stone facade with a combination of wood ventilated facades. The combination of wood and stone construction gives a historic feel and fit and existing buildings, which will carry the dominant built-up area. The new building is set into the sloping terrain with a flair for existing buildings. The building is part sunk into the ground to reduce the height to the surrounding area. The sports center is divided into three dilatations objects: Technical facilities, sports hall, bowling with squash and gym.
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Novotný, Zdeněk. "Centrální objekt nemocnice v Uherském Hradišti - stavebně technologická příprava stavby." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2015. http://www.nusl.cz/ntk/nusl-227165.
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This diploma thesis deals with construction and technological preparation of the construction of the central hospital building in the town Uherske Hradiste. The work is composed of selected parts of the building and technological project, which is annexed to the diploma thesis. On some selected parts of the building and technological project is also prepared relevant drawings. The aim of the thesis is to choose a suitable and effective implementation process object depending on the circumstances and determine the resources of time, funds, personnel and materials.
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Lacheta, Lukáš. "Pomocná brzda pro eskalátor." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2008. http://www.nusl.cz/ntk/nusl-227977.
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Purpose of engaged task is elaborate a functional mechanism to emergency brake for escalators company Otis. To this purpose is gradually reached up in several phases. In primary phase was taken view on similar products from competitive company and do not get in conflict with patent right, in second phase was needed delimitate working space for brake and exact specification of straining. In next steps the proposal and test phase is blending together. In this moment emergency brake has own shape and first tests are showing the functions, but as well necessity modification of same elements on brake and on escalator.
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Ming-de, SHEN, and 沈明德. "Prediction Method of Air Pressure on Building Vertical Drainage Stacks." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/67036715374031163985.
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碩士國立臺灣科技大學
建築系
92
The sewerage system of a building has a concern in the environmental public health and sanitation. Especially under the trend and development of towering buildings and high-density of population, inappropriate sewerage system can cause many problems, including sanitary facilities trap seal water drains,bad drainage and so on. Particularly the epidemic disease — SARS that evoked international panic in 2002, after some research and investigation, researchers confirmed that sewerage system of a building is one of the channels of infection. Therefore, to ensure a building has the most appropriate sewerage system and to prevent lethal and contagious virus from spreading are the most important functions that an appropriate sewerage system has to cover. This research continues domestic experiences on buildings’ sewerage system to keep making research project and plan on the aerating quality and function the ventilates performance of vertical drainpipe that affects the function of trap in sanitary facilities, and also to keep experimental analysis on air pressure variation inside the single drainpipe system in order to establish a thorough and complete predictable mode on them.In the meantime, based on the vertical dual drainpipe that is commonly and domestically used to build up an experimental system; with the reference from experimental parameter, we combine the predictive mode on single vertical drainpipe, and expand to estimate the air pressure variation maximum range on dual drainpipe as the further evaluation on the drainage system and as the theory foundation on piping design and arrangement. The research results found are as below: 1.To complete the proof and experiment of air pressure variation inside the vertical single drainpipe and to establish distribution predictive mode. 2.To establish the experimental equipment on duel vertical aerating drainpipe, and to confirm it qualifies with closeness that is required in this experimental system. 3.To finish analysis on air pressure variation experiments and function of dual pipes drainage system. 4.To set up the predictable mode of air pressure variation maximum range. 5.To complete the experimental proof and discussion on the air-pressure variation predictive mode between single vertical pipe and dual vertical pipes.
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Palacharla, Gopalkrishna. "Three dimensional localised slant stacks and their application to the analysis of synthetic reverse vertical seismic profiles." Thesis, 1992. http://hdl.handle.net/1911/13638.
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Three-dimensional slant stacks simulate the response of an elastic medium for both an incident (ray parameter q) and a scattered (ray parameter p) plane wave and are implemented by following a slant stack of common shot gathers by a second slant stack of common ray parameter gathers. Three-dimensional localised slant stacks are developed, and applied to analyse reverse vertical seismic profiles. The application of slant stacks to borehole data differs from the surface seismic case in that the velocities measured from plane wave decomposition are horizontal and vertical phase velocities. Velocity and dip estimates for a model with iso-velocity layers and plane interfaces with any dip are obtained using the slant stacks without explicitly utilizing traveltimes. The estimation scheme is based on a layer stripping approach. The direct arrivals are used to determine the velocity and the reflections are used to determine the dip of the reflector.
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Ramirez-Iraheta, Oscar A. "Passive and mixed-convective cooling of vertical stacks of heat-generating bodies in a square cavity with openings." 2004. http://hdl.handle.net/1993/15757.
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Lee, He-lin, and 李和臨. "A Nonvolatile Two-Bits SONOS Memory with Vertical Oxide-Nitride-Oxide Stack." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/upayuw.
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碩士國立中山大學
電機工程學系研究所
95
Flash memory is one sort of non-volatile memory, focus on the dates holding and capacity. Conventional non-volatile memory applies poly-crystalline for floating gate material, because the poly-crystalline (like poly-silicon) itself is the semiconductor material, will cause leakage problem, recently, Oxide-nitride-oxide multi-layer structure is under development for the place of conventional floating gate. Because it is the insulator material, can suppress leakage current, and it contains a deeper trapping energy level, and has a partial trapped carriers phenomenon to give a multi-bits memory solution. My effort is to propose a pair of ONO three layers stack, which is located close to the beneath of D/S region and a column like. Such structure can overcome miniaturization limitation of channel length, and a somewhat depth oxide can promise good isolation and separation between the trapping layer and other area, and a reliable distance of the two trapped unit can prevent interference issue. My proposal can suppose a higher devices density and a feasible and flexible solution to develop memory devices, a cost down to be more competitive, certainly bring much favor for the future improvement.
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Buckley, John G., Stephen F. Jones, and Louise Johnson. "Age-differences in the free vertical moment during step descent." 2009. http://hdl.handle.net/10454/15843.
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NoThis study utilises a rarely examined biomechanical parameter – the free vertical moment to determine age-related differences in rotational kinetics of the body about the vertical-axis when stepping down from a stationary position. Ten older and 10 young adults completed step-downs from three heights. Free vertical moment impulse and peak during step-initiation double-support and the subsequent step-execution phase, and vertical-axis pelvis angular displacement and velocity at instant of landing were compared. The free vertical moment during double-support was directed away from the intended leadlimb side, producing a change in vertical-axis rotational momentum that moved the lead-limb in a forwards- medial direction about the stationary support/trailing limb during the subsequent step-execution phase. The free vertical moment during step-execution was directed towards the lead-limb side and acted to slow/halt the body’s vertical-axis rotation away from lead-limb side. Free vertical moment impulse and peak during double-support were similar between groups (P > 0.05), but during step-execution were significantly reduced in older adults (P = 0.002). As a result older adults had greater verticalaxis pelvis angular displacement and velocity at instant of landing (directed away from lead-limb side), with significant (P < 0.001) group-by-step height interactions indicating that differences between groups became more pronounced with increasing step-height. These findings highlight that older adults were unable to exert the same vertical-axis control during single-support as young subjects did. Findings also highlight that the analysis of free vertical moment data can be a useful biomechanical tool to highlight age-related differences in how steps/stairs are negotiated.
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Tai, Chen-Fang, and 戴禎坊. "Vertical Stacked Yagi-Uda Antenna Embedded-in LTCC Substrate for 60GHz Application." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/08136811855346162131.
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碩士國立臺灣大學
電信工程學研究所
98
Yagi-Uda is one of the most popular antennas for all applications. It usually has three parts, including a radiator, several directors and several reflectors. Yagi-Uda antenna can be easily designed and achieve relatively high gain. For example, a properly designed three-element Yagi-Uda antenna can achieve gain of about 7~8dB. Therefore, Yagi-Uda is good for use in point-to-point wireless communication. In this thesis, we proposed a new structure that is a stacking Yagi-Uda antenna in LTCC substrate and operating in V-band. Five different types of Yagi-Uda antenna for different radiation directions are presented. Also transmitting and receiving modules integrated with embedded stacked Yagi-Uda antenna and flip-chip dies are also shown. Design procedures, simulation results and measurement results for all designs are given. The measured typical gain of antenna for vertical radiation is about 4~5dB.
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Hung, Yu-Wen, and 洪彧彣. "Investigation on Stress Instability of Junctionless FET with Vertical Stacked Multi-Channels." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/5sphvn.
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Cheng, Hui-Yu, and 鄭慧妤. "Symmetry of Vertically Stacked 2D Transition Metal Dichalcogenides." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/a55ca5.
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碩士國立交通大學
電子物理系所
107
Vertically stacked heterostructures made of atomically thin two-dimensional (2D) layered materials, such as graphene, boron nitride, and transition metal dichalcogenides (TMDs), have recently attracted much attention due to their versatility in creating functional artificial materials. Replacing the constituent materials and controlling the structure pave the way for future designing of heterostructure devices. 2D PdSe2 crystal is a member of 2D TMDs, featuring a unique puckered pentagonal structure with in-plane anisotropy, and is theoretically predicted to exhibit a widely tunable bandgap. In this thesis, we demonstrate that the layer number and crystal anisotropy of 2D PdSe2 can be identified by polarization-resolved Raman spectroscopy and second harmonic generation (SHG). The strong interlayer interaction in 2D PdSe2 is revealed by measuring the interlayer breathing mode in low-frequency Raman spectroscopy, which can be well predicted by the conventional linear chain model corrected by the minor interlayer restoring forces. The layer number is further confirmed by SHG, where a strong SHG signal can be observed in the even-layer PdSe2 non-centrosymmetric, and a nearly vanished SHG in odd-layer PdSe2. Polarization-resolved Raman and SHG measurements also reveal in-plane anisotropy, which is consistent with the crystallographic axes determined by transmission electron microscopy. On the other hand, we also demonstrate that the low-frequency Raman spectroscopy can be used to identify the stacking configuration of WS2/MoS2 heterobilayers. WS2/MoS2 heterobilayer formed by vertical CVD grown of WS2 on MoS2. Since its electronic and optical properties strongly depend on the stacking configuration due to the symmetry-dependent interlayer coupling, we found that the stacking configuration of TMD heterobilayers can be characterized by low-frequency (< 60 cm-1) shear and breathing Raman modes, corresponding to in-plane and out-of-plane layer vibrations, respectively.
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Chang, Yu Shuo, and 張佑碩. "Study of Vertically Stacked Poly-Si Nanosheet Field-Effect-Transistor." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/38303284729222024224.
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碩士國立清華大學
工程與系統科學系
104
The market demand for portable electrical equipments increase dramatically year by year., emphasizing on multifunctional, small size, light weight, etc. Under keen mutual competition environment of economic market and electronic industries, it has triggered electronic industries to improve their products to develop toward low cost, high density and scale down to react to the rapid demand in the market. Nevertheless, the expectation of scaling transistors suffered more and more difficult to design, whether the short channel effect in devices or the challenge of fabrication process are very vital research topics. In this thesis, we successfully demonstrate the stacked nanosheert(NS) vertically inversion-mode field-effect-transistors(VM-FET) in 3D stacked integrated circuit (IC) applications to increase transistor density for continuing Moore’s law. It may offer valuable information with regard to their practical industry and academic applications. This research which focus on is showing the following: (1) device process, (2).basic device characteristics analysis, (3) device simulation. In the fabrication process, we adopt the oxidation trimming method to form thin active layer and exhibit quasi-crystal channel due to the reduction of grain boundaries and defects. It is beneficial for excellent electrical performance. In the basic device characteristics analysis. First part will show the comparison of stacked NS VM-FET and conventional NS IM-FET. The stacked structure exhibits the better characteristics owing to due to the parallel resistance, resulting in smaller total resistance and improved around 4.36 times current drivability and higher ON/OFF current ratio up to 108. The 3D stacked layer can increase on-state current and maintain low leakage current. Second part will discuss about the change of width dimension for I-V characteristics with stacked structure. However, in the device simulation, we use Sentaurus TCAD to analyze and confirm the measured basic electrical characteristics As a result, we proposed the stacked NS VM-FET has better electrical characteristics. Additionally, it may offer a possible next-generation CMOS device solution and be applied in advanced system-on-chip and 3D stacked IC applications.
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Lai, Hsiang-Yueh, and 賴香月. "A Study on the Incorporation of A Novel Vertical Structure and A Stack Tunnel Dielectric for Flash Memory Devices." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/47644855058522747057.
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博士國立清華大學
工程與系統科學系
98
摘要 快閃記憶體已愈來愈重要並廣泛地應用於日常生活中。為改善快閃記憶體之操作特性，及解決元件微縮過程中所面臨之問題，本文提出利用堆疊結構穿隧介電層之快閃記憶體，並另設計新型垂直結構搭配矽化鍺材料之快閃記憶體。 本文設計兩類之快閃記憶體穿隧介電層: 第一類為利用單層Si3N4或不同組成比之Si3N4/ SiO2堆疊結構，再配合不同溫度之快速熱處理；第二類為利用單層HfOXNY或不同組成比之 HfOXNY/ SiO2堆疊結構，再配合不同溫度之快速熱處理。 由實驗知，堆疊結構較單層穿隧介電層之操作特性佳。於第一類元件：堆疊結構之穿隧介電層中，厚的Si3N4搭配薄的SiO2堆疊結構之穿隧介電層，擁有較佳之元件操作特性；不同溫度之快速熱處理中，800 oC快速熱處理之穿隧介電層，擁有較佳之元件操作特性。於第二類元件：堆疊結構之穿隧介電層中，厚的HfOXNY搭配薄的SiO2堆疊結構之穿隧介電層，擁有最佳之元件操作特性；不同溫度之快速熱處理中，850 oC快速熱處理之穿隧介電層，擁有最佳之元件操作特性。 避免元件微縮過程中所面臨之問題，本文應用元件模擬軟體MEDICI 設計不同垂直結構並配合不同操作條件之快閃記憶體。搭配矽/矽化鍺異質接於面垂直結構雙閘極快閃記憶體，擁有較佳之元件操作特性。隨著增加矽化鍺之鍺含量於搭配矽/矽化鍺異質接面之垂直結構雙閘極快閃記憶體，快閃記憶體之操作特性跟著改善。
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Yang, Yi-Yun, and 楊怡芸. "Study of Vertically Stacked Nanosheet With Multi- Gate Field-Effect-Transistors." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/jfhv3s.
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碩士國立清華大學
工程與系統科學系
105
In recreant years, the electronic products pursue not only the higher speed and better performance, but also less power consumption and lower cost. The Semiconductor ICs manufacturing companies still follow Moore's law to scaling. In addition to processing technology feasibility limits, it is important to develop a target that suffices high performance and scalability. Information processing technology is driving the semiconductor into a broadening spectrum of new applications according to 2015 ITRS 2.0 report. A significant part of the research to further improve device performance is presently concentrated on III-V materials and Ge. These materials promise higher mobility than Si devices. The combination of 3D device architecture and low power device will usher the Era of Scaling, identified in short as “3D Power Scaling”. In order to increase transistor density for continuing Moore’s law, we implement the stacked nanosheert (NS) vertically inversion-mode field-effect-transistors(VM-FET) in 3D stacked integrated circuit (IC) applications. This research which focus on is showing the following: (1) device process, (2).basic device characteristics analysis, (3) device simulation. There are three kinds device structure. The first one is stacked Fin-FET, The second is stacked Gate all around VM-FET, The third is p-Channel Silicon/Germanium Quantum Well Multi-Gate Field-Effect-Transistor, we adopt the oxidation trimming method to form thin active layer and exhibit quasi-crystal channel due to the reduction of grain boundaries and defects. It is beneficial for excellent electrical performance. In the basic device characteristics analysis. First part will show the comparison of stacked Fin-FET and conventional stacked planar Fin-FET. The stacked Fin-FET exhibits the better performance. After that comparison of stacked Fin-FET and stacked GAA-FET. The stacked GAA-FET achieves lowing subthreshold swing (S.S.) and Off current. Second part will discuss about the change of width dimension for I-V characteristics with stacked structure. However, in the device simulation, we use Sentaurus TCAD to analyze and confirm the measured basic electrical characteristics. In our proposed the stacked NS VM-FET has better electrical characteristics. Moreover, it may provide a probable next-generation CMOS device solution and be utilized in advanced 3D stacked IC applications.
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Hsu, Tzu-Jung, and 許祖榮. "Characteristics of Field-emitting Vacuum-Channel Device of Vertically Stacked Structure." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/7mx4jg.
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Peng, Kang-Hui, and 彭康烠. "Vertically Stacked Nanosheet Junctionless With Gate All Around Field-Effect-Transistors." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/mz2na2.
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陳柏皓. "Effect of Low-Temperature Formed Dielectrics and Vertical Gate 3D Stacked Junctionless Charge Trapping Flash Memory Devices." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/twfnrn.
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碩士國立清華大學
工程與系統科學系
103
The scale down of flash device is limited by its micro-miniature planar devices, which makes the process flow more complex. How to improve the electrical characteristics and increase the device density at the same time becomes two of the most important issues. Some approaches have been reported such as the BE-SONOS, nanowire channel structure, junctionless (JL) channel and 3D array flash memory devices. In this thesis, a 3D stacked structure is implemented in charge trapping (CT) flash memory devices with high-k stacks to increase device density. Besides, the performance can be improved by HfO2/Si3N4 stacked trapping layers. In the first study, a CT flash device with stackable vertical gate structure is demonstrated for 3D memory integration. It is found that the program/erase (P/E) speeds and reliability of top and bottom devices are similar. Small program disturb and large disturb-free window are achieved. However, a conventional SONOS dielectric layer is used on JL channel flash memory devices. The erasing speed is still an issue and it need to be improved. In the second study, the HfO2/Si3N4 stacked trapping layers are implemented on the same vertical gate structure as the first study. We want to know if the stacked trapping layers can improve the erasing performance on this device. The results show that the devices exhibit better programming speed and reliability. Besides, erasing speed becomes faster by using bandgap engineering trapping layers. In the last study, although HfO2/Si3N4 stacked trapping layer plays an important role on flash memory, its thermal cycle in fabrication process may induce the degradation of trapping layers in 3D structure devices. To reduce thermal cycle, a low-temperature formed Si3N4 is used to replace the conventional one. The low-temperature formed Si3N4 is deposited by inductively coupled plasma chemical vapor deposition (ICPCVD), and a high-temperature formed one is conventionally deposited by a low pressure chemical vapor deposition (LPCVD). From the energy-dispersive spectroscopy, the compositions of Si3N4 layers are different, result in that P/E speed of ICP sample is faster than that of LPCVD one. Besides, LPCVD sample has better retention than ICP one.
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Li, Dong Yan, and 李東諺. "Low-Temperature Formed Dielectrics and Stacked Vertical Gate on Characteristics of Junctionless Charge Trapping Flash Memory Devices." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/2dys74.
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碩士國立清華大學
工程與系統科學系
104
The scaling trend of flash device is limited by the dimension of planar device, which makes the process flow more complex. How to improve the operational characteristics and increase the device density at the same time become two of the most important issues. Some approaches have been reported such as high-k material, nanowire channel structure, junctionless (JL) channel and 3D array flash memory devices. In this thesis, a low temperature formed SiO2 is proposed as tunneling layer for nano-wire and stacked vertical gate structure charge trapping (CT) flash memory devices. The purposes are to reduce thermal budget and increase device density. In the first study, a low temperature formed SiO2 is proposed to replace conventional high temperature SiO2 as tunneling layer. HfO2/Si3N4 stacked trapping layers are implemented to improve the operational characteristics of nano-wire inversion mode flash device. It is found that operational characteristics such as program/erase (P/E) speed、retention and endurance characteristics of low temperature formed SiO2 are as good as those with high temperature formed SiO2. HfO2/Si3N4 stacked trapping layers device has better P/E speed and good reliability characteristics truely. In the second study, a low temperature formed SiO2 is used as tunneling layer and HfO2/Si3N4 stacked trapping layers to improve the operational characteristics of nano-wire junctionless device. It is found that HfO2/Si3N4 stacked trapping layers device has good P/E speed、memory window and reliability characteristics. Therefore, low temperature formed SiO2 is promising to be applied to 3-D stacked device. In the last study, low temperature formed SiO2 is applied to stacked vertical gate structure. Effect of HfO2/Si3N4 stacked trapping layers on operational characteristics of the stacked vertical gate device is also studied. It is found that HfO2/Si3N4 stacked trapping layers device improves its P/E speed、retention and endrance characteristics truly. However, the reliability characteristics of all devices are not good enough. Therefore, improvement of ICPCVD formed SiO2 is necessary on such a stacked vertical gate structure.
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Ling, Chia-yu, and 凌嘉佑. "Low-Temperature Formed Dielectrics and Tri-gate Structure on Stacked Vertical Gate Junctionless CT Flash Memory Devices." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/55077749317701204188.
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Chin, Chun-Chieh, and 秦俊傑. "Vertically Stacked n-Type Poly-Si Junctionless Nanowire Transistor and Its Series Resistance." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/42ebk6.
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碩士國立交通大學
電子物理系所
105
Vertically stacked nanowire transistors are considered as the most promising candidate to fulfill the concept of three dimensional integrated circuits. In this research, the vertically stacked nanowire transistor has been successfully fabricated. Moreover, the high-k metal gate was introduced owing to the merits of low thermal budgets. However, the disproportional phenomenon of drive current enhancement with increment of layers caused by the series resistance issue for vertically stacked structure has been experimentally addressed. First of all, the fully suspended nanowire transistor was successfully fabricated for demonstration purpose and the electrical transfer characteristics with four different thermal treatments were also discussed. For RTA_500℃_H2/N2_30s, the drive current (Ion) under the same over-drive of 2V improves from 0.81uA to 1.02uA. Furthermore, this condition also leaves the threshold voltage and Imin unchanged. On the other hand, the subthreshold characteristics of S.S. and DIBL also improves from 278mV/dec to 226mV/dec, respectively. Finally, the normalized series resistance for channel counts of 2, 10 and 20 is nearly the same and the value is around A, B and C respectively. Therefore, the drive current can be enhanced proportionally. Next, the vertically stacked nanowire transistor was fabricated with the introduction of high-k metal gate for low thermal budget purpose. The drive current per footprint can be effectively enhanced with the increment of layers from 1.24uA to 1.83uA. However, the subthreshold characteristics of S.S. and DIBL were slightly degraded with the increment of layers. Moreover, the comparison between PDA and PPO treatment were also conducted. The drive current (ID) of PDA of 1.22uA is higher than PPO of 1.02uA due to the interface quality and improved subthreshold swing under the same over drive of 2V. Moreover, the subthreshold characteristics of S.S. and DIBL also improves from 370mV/dec to 143mV/dec, respectively. Eventually, the series resistance issue was experimentally demonstrated by three different approaches. The analysis shows that the series resistance of bottom layer is definitely larger than upper layer which cause the disproportional phenomenon of drive current enhancement with the increment of layers.
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Chang, Chih-Yao, and 張智堯. "Investigation on Vertically Stacked Gate-All-Around Nanosheet Poly-Si Junctionless CMOS Transistors." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/459ufp.
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碩士國立交通大學
電子物理系所
107
The GAA Nanosheet Poly-Si JL FETs have been successfully fabricated by only two simple steps that the dry etching process follows by wet etching. The dimension of gate stack of WM = 40 nm with Hp,1 × Wp,1 of top layer poly-Si is 8 nm × 30 nm, and Weff is 76 nm. Then, we comprehensively discuss the electrical characteristic of the GAA Nanosheet Poly-Si JL FETs with two different type MOS transistors, gate length and channel width. Furthermore, vertically multiple channel architecture devices are also have been successfully fabricated by the same process and behave superior electrostatic control ability and subthreshold characteristics performance. The on-state-current in two different type have significantly boosted up, respectively. The floating-gate-induced gate control ability degradation resulting is observed from single channel devices. It is attributed to the difference of doping profile. Furthermore, we discover that through the adjustment of energy of ion implantation, the ION of 2 Layer Nanosheet n-type JL FETs has effectively boosted up close the level of 2 Layer Nanosheet p-type JL FETs. Finally, the VTC of CMOS inverter display a most perfect performance of the VTC of CMOS inverter.
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Chang, Cheng-Han, and 張正翰. "Optically and Electrically Readable Glucose Sensors Derived from Graphene Vertically Stacked Multiple Heterojunctions." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/v56t9v.
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碩士國立臺灣大學
物理學研究所
107
Optically and electrically readable glucose sensors based on high quality graphene vertically stacked heterojunctions with ultrahigh sensitivity has been designed, fabricated and demonstrated. Its sensing mechanism makes use of the large variation in the Fermi energy of graphene upon electrons doping from oxygen molecules generated by electrochemical process of glucose oxidase at the presence of glucose molecule. A semiconductor sieve layer with suitable band alignment to prevent charge transfer from graphene can greatly enhance the sensitivity. And an insulating layer to create electron-hole pairs accumulation near the interface is very useful for light emission. Combining all these unique features together, it results in superior detection both in optical and electric performance. Through measurements of current-voltage characteristics and electroluminescence spectra, this novel structure responds to glucose concentrations covering a wide range from as low as 1 nM to 100 mM. All these superior properties show a great potential for the development of portable, noninvasive, and parallel readable glucose sensors.
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Hsu, Fu-Chieh, and 許富傑. "Vertically Stacked High Order Stepped-Impedance Resonator (SIR) Bandpass Filters with a Dual-Passband Response." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/63251053568970620168.
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碩士國立交通大學
電信工程系所
94
A rigorous synthesis method is presented for higher order microstrip bandpass filters with a dual-passband response in vertical stack configuration. The building block of the circuit is stepped-impedance resonator (SIR) of which resonant frequencies can be tuned by simply adjusting its structure parameters. Fractional bandwidth design graphs are established for determining offset and space between adjacent resonators. The impedance and length ratios of the SIR should be properly chosen so that all couplings between any two adjacent resonators can fulfill the design figures given by the element values of the lowpass prototype. Second-, sixth- and eighth-order bandpass filters are designed and fabricated. Measured results of the three fabricated circuits show good agreement with the simulated responses.
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Steht, Markus von [Verfasser]. "Imaging of vertical seismic profiling data using the common-reflection-surface stack = Abbildungsverfahren für seismische Daten aus Bohrlochmessungen mit der Common-reflection-surface-Stapelung / von Markus von Steht." 2008. http://d-nb.info/988527480/34.
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Chen, Yu-san, and 陳友三. "The Application and Study of Transparent Electrode in Vertically Stacked Organic Light-Emitting Diodes with Function of Individually Controllable Electrodes." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/39105881490768024017.
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碩士國立臺灣科技大學
電子工程系
101
This thesis is for designing an organic light emitting diode which unit sub-pixel has the function of adjusting color and luminance. It can emit colorful lights or white light by combination. The thesis will reach the concept by making a vertical stacked organic light emitting diode that stacking several organic light emitting diodes and retaining the control function of each cell. In thesis, we used standard structure blue light diode stacking inverted structure green light diode and share the middle transparent cathode to reduce the diode complexity and the number of electrodes. The structure of stacked organic light emitting diode with individual controllable electrode layer had never been developed before this thesis in our laboratory, and therefore the thesis will focus on two focal points to study and investigate: the establishment of vertical stacked device platform and optimization of middle transparent cathode. The experiment used fluorescent material MADN as emitting layer of standard structure blue light cell; fluorescent material Alq3 as emitting layer of inverted structure green light cell, By optimized the n-type doping injection layer and inverted structure device , the resulting structures were blue light cell: ITO/NPB(50 nm)/MADN(55 nm)/Bphen:Cs2CO3 [10%](10 nm)/Ag(100 nm) and green light cell: ITO/ Bphen:Cs2CO3 [10%](10 nm)/Alq3(40 nm)/NPB(50 nm)/WO3 (20 nm)/ Al (120 nm). After establishing each device structure, we stacked them and applied WO3/Ag(14 nm)/WO3 for transparent cathode to replace the reflected cathode of original structure. According to optimized experiment result, the vertical stacked device structure is: ITO/NPB(50 nm)/MADN(55 nm)/Bphen:Cs2CO3 [10%](10 nm)/Ag(14 nm)/Bphen:Cs2CO3 [10%](10 nm)/Alq3(40 nm)/NPB(50 nm)/ WO3 (20 nm)/Al (120 nm), which each electrically and efficiency can reach the same compared to single devices. In the same experiment, we also discovered the microcavity effects result from middle transparent electrode. The microcavity effect has considerable effect on modulating emission spectrum. With a proper designed microcavity structure, we could narrow the light-emitting spectrum for display application and broaden the light-emitting spectrum for lighting application.
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Elliott, David B., Richard J. Foster, David J. Whitaker, Andy J. Scally, and John G. Buckley. "Analysis of lower limb movement to determine the effect of manipulating the appearance of stairs to improve safety: a linked series of laboratory-based, repeated measures studies." 2015. http://hdl.handle.net/10454/8225.
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yesBackground: Falls on stairs are a common and dangerous problem for older people. This series of studies evaluated whether or not selected changes to the appearance of stairs could make them safer for older people to negotiate. Objectives: To determine the effect of (1) a step edge highlighter and its position and (2) an optimised horizontal–vertical (H–V) visual illusion placed on a step riser on gait safety during stair descent and ascent. Design: A series of studies using a repeated measures, laboratory-based design, investigating gait control and safety in independently mobile older people. Setting: The University of Bradford Vision and Mobility Laboratory. Participants: Fit and healthy older people aged 60 years of age or more, independently mobile, reasonably active and with normal healthy eyes and corrected vision. Interventions: A step edge highlighter in a variety of offsets from the stair edge and an optimised H–V visual illusion placed on the stair riser. The H–V illusion was provided on a staircase by horizontal step edge highlighters on the tread edges and vertical stripes on the step risers. Main outcome measures: Gait parameters that are important for safe stepping in ascent and descent, particularly toe clearance during stair ascent and heel clearance during stair descent. Results: The step edge highlighter increased the precision of heel clearance during stepping and its positioning relative to the tread edge determined the extent of heel clearance over the tread edge. Positioning the highlighter away from the tread edge, as is not uncommonly provided by friction strips, decreased heel clearance significantly and led to greater heel scuffs. Although psychophysics experiments suggested that higher spatial frequencies of the H–V illusion might provide greater toe clearance on stair ascent, gait trials showed similar increased toe clearances for all spatial frequencies. When a 12 cycle per step spatial frequency H–V illusion was used, toe clearance increases of approximately 1 cm (17.5%) occurred without any accompanying changes in other important gait parameters or stability measures. Conclusions: High-contrast tread edge highlighters present on steps and stairs and positioned flush with the edge of the tread or as near to this as possible should improve stair descent safety in older people. A H–V illusion positioned on the riser of a raised surface/walkway (e.g. kerbs) and/or the top and/or bottom of a stairway is likely to increase foot clearance over the associated step/stair edge, and appears not to lead to any decrement in postural stability. Thus, their use is likely to reduce trip risk and hence improve stair ascent safety. The effect of the step and stair modifications should be assessed in older people with visual impairment. The only other remaining assessment that could be made would be to assess fall prevalence on steps and stairs, perhaps in public buildings, with and without these modifications.
National Institute for Health Research, Public Health Research programme. PHR programme as project number 10/3009/06
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Kaufmann, Stefan. "Vascular plant and cryptogam diversity in Fagus sylvatica primeval forests and comparison to production stands in the western Carpathian Mountains, Slovakia." Thesis, 2018. http://hdl.handle.net/21.11130/00-1735-0000-0003-C123-B.
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