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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.
1

Eficiência da manipueira como quelatizante de zinco e seu efeito na nutrição mineral do feijoeiro (Phaseolus vulgaris L.) / THE EFFICIENCY OF MANIPUEIRA AS A ZINC CHELATE, AND ITS EFFECT ON ROOT GROWTH AND MINERAL NUTRITION IN BEAN CULTIVATION.

Melo, Vítor e Silva 25 May 2010 (has links)
Cassava (Manihot esculenta, Crantz) is considered a vital agricultural crop due to its role as a staple food for low-income populations, primarily in the North and Northeast of Brazil, and is used as raw material for the manufacturing of a number of products such as flour and starch. During the manufacturing of these products, a potentially toxic liquid residue called manipueira is produced. Due to its high content of hydrogen cyanide (HCN), this residue (which originates during the initial processing stages of the cassava) has very limited use. After undergoing a process of HCN volatilization however, it may then be used for the fertilization, to create insecticides, nematicides and herbicides. Manipueira has contains glucose, cyanogenic glycosides, organic substances and mineral nutrients, in particular potassium (K), nitrogen (N), as well as micronutrients - all guaranteeing its potential as a fertilizer. The aim of this study was to evaluate the effect of cassava as an alternative to zinc chelates in bean cultivation. The study was carried out in a greenhouse at the Federal University of Sergipe. The experimental design involved random blocks in 5x4 factorial arrangement, with five repetitions and five treatment sources: The experimental design was randomized blocks in a factorial arrangement 5 x 4, the treatments were five sources (A-H2O; Manipueira1 B-2 ml dm-3, C-4 manipueira2 ml dm-3, D-manipueira3 8mL dm3, E-EDTA) with four levels of zinc (0,0; 1,3;2,6 and 5,2 mg Zn dm3), applied to the soil, whit four replication. The soil was collected from the rural campus at the Federal University of Sergipe and a sample was taken for chemical analysis. The soil was placed in 16 L-1 b plastic bags and dolomitic lime was used for liming of the soil. The fertilizations were performed with 100 mg of phosphorus (P) dm-3 and 100mg of potassium (K) dm-3, in the form of triple super phosphate and potassium chloride. The lime and fertilizers were combined with the soil contained in the plastic bags and were then transferred to 100 containers with a soil capacity of 13 dm-3. A quantity of 50 mg of N dm-3 in the form of urea was applied for sowing fertilization. Sowing was carried out using six Pearl bean cultivar seeds per container. Seven days after the emergence of shoots, thinning was carried out to remove plant surplus, leaving two plants per container, and the treatments were applied. Once most of the plants had reached the phenological stage of flowering (R6) harvesting was carried out. The parameters examined were physico-chemical analysis (in the manipueira) and growth and nutritional analyses in the bean plant tissue (leaf and root). The use of cassava as quelatizante of micronutrients on dry bean crop had a satisfactory result in treatments EDTA and Man ¹.If necessary more studies of manipueira as chelate micronutrients in other cultures. / A mandioca (Manihot esculenta Crantz) é uma cultura agrícola muito importante por constituir a base alimentar das populações de baixa renda principalmente na região Nordeste, sendo matéria prima na fabricação de diversos produtos como a farinha e fécula. No processo de fabricação destes produtos é gerado a manipueira um resíduo líquido potencialmente poluidor a manipueira. Este resíduo, originado nas etapas de processamento da mandioca tem aproveitamento muito restrito por apresentar alto teor de ácido cianídrico (HCN).No entanto, com a volatilização do HCN a manipueira pode ser usada como fertilizante, inseticida, nematicida e herbicida. A manipueira possui principalmente glicose, glicosídeos cianogênicos, substâncias orgânicas e elementos minerais, como K, N e micronutrientes que sustentam a potencialidade como adubo. A presente pesquisa teve como objetivo avaliar o efeito da manipueira como alternativa de quelatizante de zinco para o feijoeiro (Phaseolus vulgaris L.). O trabalho foi desenvolvido na Universidade Federal de Sergipe em condição de casa de vegetação. O delineamento experimental utilizado foi em blocos casualizados, disposto em arranjo fatorial 5 x 4, sendo que os tratamentos foram cinco fontes (A H2O; B- Manipueira1 (2 ml dm-3), C manipueira2 (4 ml dm-3); D manipueira3 (8 mL dm-3); E- EDTA) e quatro níveis de zinco (0,0; 1,3; 2,6 e 5,2 mg.dm-3 de Zn), aplicados no solo, com quatro repetições. O solo utilizado como substrato foi proveniente do campus Rural da Universidade Federal de Sergipe, foi retirada uma amostra para análise química.Após a coleta do solo, este foi colocado em sacos de plásticos de 16 L-1. Posteriormente, foi realizada a calagem, com calcário dolomítico, e em seguida foram realizadas as adubações com 100 mg.dm-3 de P, 100 mg.dm-3 de K. O calcário e os adubos foram misturados ao solo contido nos sacos plásticos e transferidos para os 100 vasos com capacidade de 13 dm3 de solo. Na adubação de semeadura foram aplicados 50 mg.dm-3 de N, na forma de uréia. A semeadura foi realizada utilizando seis sementes de feijão da Cv. Pérola por vaso. Após sete dias da emergência das plântulas foram realizados os desbastes, deixando duas plantas por vaso, e em seguida aplicados os tratamentos.Quando a maioria das plantas estavam no estádio fenológico de floração (R6) foi realizada a colheita dos tratamentos. Verificou-se que as aplicações de quelato biológico (manipueira) no solo resultaram em teores crescente de zinco na parte aérea do feijoeiro. Os ácidos orgânicos da manipueira apresentou-se eficiente na quelatização dos nutrientes estudados.
2

Posouzení úrovně výživy ve vztahu k produkci mléka u dojnic / Assessment of the Level of Nutrition and its Relationship to Milk Production in Milk Cows

HORKÝ, Jan January 2015 (has links)
In the ZD Kojčice cooperative farm, a stable in Krasíkovice was studied in 2013 and 2014. The farm's production technology and the quality of the ensiled feed, feeding techniques, composition of the feed portions and selected milk production indicators were examined. The economy of milk production was also assessed. The production of ensilage ensured quality feed that was the basis for the milk cows' feed portions. The results show that the feed portions were well balanced in comparison to the recommended nutritional values for milk cows. The average yield in 2014, unlike 2013, decreased by 146 l to 5 960 l per milk cow per year. The costs per feed day were established at 138,2 Kč. The average costs for one liter of milk were 8,75 Kč/l.
3

Eficiência econômica da produção de cana-de-açúcar de produtores independentes do Estado do Paraná

Melo, Cármem Ozana de [UNESP] 04 November 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:36Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-11-04Bitstream added on 2014-06-13T20:42:06Z : No. of bitstreams: 1 melo_co_dr_botfca.pdf: 2377972 bytes, checksum: 5bce18fd2c93afa81e3571005df49658 (MD5) / A disponibilidade e uso de energia é fator fundamental para o crescimento e desenvolvimento de qualquer país. Entretanto, é necessário que tal aspecto se processe de forma sustentável. Com isso, ganha importância a busca de fontes alternativas de energia, que atente para questões ambientais, sociais e econômicas. Neste contexto, a agroenergia tem papel de destaque, por ser uma fonte de energia renovável e limpa. No Brasil, realce se dá para a cana-de-açúcar, que desde os primórdios tem participação relevante e, a partir da década de 1970 passou a figurar como importante fonte de energia, substituindo em parte o uso do petróleo. A partir da década de 1980 e mais intensamente da década de 1990, com a aberturada economia brasileira, este setor vivenciou importantes transformações, passando a atuar em ambiente de livre mercado, o que exigiu dos agentes envolvidos maior competitividade e eficiência a fim de permanecer na atividade. As empresas participantes deste segmento adotaram estratégias que levaram à concentração da produção nas grandes usinas, fusões, verticalização da produção e exigências acerca do controle da quantidade e qualidade da matéria-prima a ser processada pela indústria. Participando desse cenário, existe a figura do produtor/fornecedor independente que também passa a ter que atuar de forma cada vez mais eficiente para atender à demanda da agroindústria e assim ter a sustentabilidade econômica. Neste sentido, este trabalho tem como objetivo estimar a eficiência econômica da produção de cana-de-açúcar dos produtores independentes do estado do Paraná, onde o setor é relevante para a economia local. Com a utilização do modelo DEA-BCC – Data Envelopment Analysis com retornos varáveis à escala orientado a inputs, foi estimada a eficiência econômica das unidades produtivas (designadas como DMUs - Decison Making Units)... / The availability and use of energy is essential to the growth and development of any country. However, it is necessary for this aspect to be carried out in a sustainable way. With this, the search for alternative energy sources, that watches out for environmental, social and economic issues is becoming more vital. In this context, agroenergy has an important role, as a source of renewable and clean energy. In Brazil, an emphasis is given to the sugar cane, which has a relevant participation from the beginning and, since the 1970s was renumbered as an important energy source, replacing in part the use of petroleum. From the 1980s and more intensively in the 1990s with the opening of the Brazilian economy, this sector has experienced major changes, starting to act on the free market, which required from those involved, greater competitiveness and efficiency in order to stay in activity. Companies participating in this segment have adopted strategies that led to concentration of production in large plants, mergers, vertical integration of production and requirements about the control of the quantity and quality of raw material to be processed by the industry. Participating in this scenario, there is the figure of the independent producer / vendor which has also to act more efficiently in order to meet the demand of the agricultural industry and thus have economic sustainability. So, this study aims to estimate the economic efficiency of production of sugar cane producers of the independent state of Parana, where the sector is relevant to the local economy. Using the DEA-BCC model - Data Envelopment Analysis with variable recurrences to scale oriented inputs, was estimated economic efficiency of production units (DMUs designated as - Decison Making Units). Results showed that most of the production units surveyed did not provide the maximum economic efficiency... (Complete abstract click electronic access below)
4

Eficiência econômica da produção de cana-de-açúcar de produtores independentes do Estado do Paraná /

Melo, Cármem Ozana de, 1965- January 2010 (has links)
Orientador: Maura Seiko Tsutsui Esperancini / Banca: Osmar de Carvalho Bueno / Banca: Izabel Cristina Takitane / Banca: RobertoArruda de Souza Lima / Banca: Maria AparecidaA. Tarsitano / Resumo: A disponibilidade e uso de energia é fator fundamental para o crescimento e desenvolvimento de qualquer país. Entretanto, é necessário que tal aspecto se processe de forma sustentável. Com isso, ganha importância a busca de fontes alternativas de energia, que atente para questões ambientais, sociais e econômicas. Neste contexto, a agroenergia tem papel de destaque, por ser uma fonte de energia renovável e limpa. No Brasil, realce se dá para a cana-de-açúcar, que desde os primórdios tem participação relevante e, a partir da década de 1970 passou a figurar como importante fonte de energia, substituindo em parte o uso do petróleo. A partir da década de 1980 e mais intensamente da década de 1990, com a aberturada economia brasileira, este setor vivenciou importantes transformações, passando a atuar em ambiente de livre mercado, o que exigiu dos agentes envolvidos maior competitividade e eficiência a fim de permanecer na atividade. As empresas participantes deste segmento adotaram estratégias que levaram à concentração da produção nas grandes usinas, fusões, verticalização da produção e exigências acerca do controle da quantidade e qualidade da matéria-prima a ser processada pela indústria. Participando desse cenário, existe a figura do produtor/fornecedor independente que também passa a ter que atuar de forma cada vez mais eficiente para atender à demanda da agroindústria e assim ter a sustentabilidade econômica. Neste sentido, este trabalho tem como objetivo estimar a eficiência econômica da produção de cana-de-açúcar dos produtores independentes do estado do Paraná, onde o setor é relevante para a economia local. Com a utilização do modelo DEA-BCC - Data Envelopment Analysis com retornos varáveis à escala orientado a inputs, foi estimada a eficiência econômica das unidades produtivas (designadas como DMUs - Decison Making Units)... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The availability and use of energy is essential to the growth and development of any country. However, it is necessary for this aspect to be carried out in a sustainable way. With this, the search for alternative energy sources, that watches out for environmental, social and economic issues is becoming more vital. In this context, agroenergy has an important role, as a source of renewable and clean energy. In Brazil, an emphasis is given to the sugar cane, which has a relevant participation from the beginning and, since the 1970s was renumbered as an important energy source, replacing in part the use of petroleum. From the 1980s and more intensively in the 1990s with the opening of the Brazilian economy, this sector has experienced major changes, starting to act on the free market, which required from those involved, greater competitiveness and efficiency in order to stay in activity. Companies participating in this segment have adopted strategies that led to concentration of production in large plants, mergers, vertical integration of production and requirements about the control of the quantity and quality of raw material to be processed by the industry. Participating in this scenario, there is the figure of the independent producer / vendor which has also to act more efficiently in order to meet the demand of the agricultural industry and thus have economic sustainability. So, this study aims to estimate the economic efficiency of production of sugar cane producers of the independent state of Parana, where the sector is relevant to the local economy. Using the DEA-BCC model - Data Envelopment Analysis with variable recurrences to scale oriented inputs, was estimated economic efficiency of production units (DMUs designated as - Decison Making Units). Results showed that most of the production units surveyed did not provide the maximum economic efficiency... (Complete abstract click electronic access below) / Doutor
5

Process efficiency in polymer extrusion: Correlation between the energy demand and melt thermal stability

Abeykoon, Chamil, Kelly, Adrian L., Vera-Sorroche, Javier, Brown, Elaine C., Coates, Philip D., Deng, J., Li, K., Harkin-Jones, E., Price, M. 25 September 2014 (has links)
Yes / Thermal stability is of major importance in polymer extrusion, where product quality is dependent upon the level of melt homogeneity achieved by the extruder screw. Extrusion is an energy intensive process and optimisation of process energy usage while maintaining melt stability is necessary in order to produce good quality product at low unit cost. Optimisation of process energy usage is timely as world energy prices have increased rapidly over the last few years. In the first part of this study, a general discussion was made on the efficiency of an extruder. Then, an attempt was made to explore correlations between melt thermal stability and energy demand in polymer extrusion under different process settings and screw geometries. A commodity grade of polystyrene was extruded using a highly instrumented single screw extruder, equipped with energy consumption and melt temperature field measurement. Moreover, the melt viscosity of the experimental material was observed by using an off-line rheometer. Results showed that specific energy demand of the extruder (i.e. energy for processing of unit mass of polymer) decreased with increasing throughput whilst fluctuation in energy demand also reduced. However, the relationship between melt temperature and extruder throughput was found to be complex, with temperature varying with radial position across the melt flow. Moreover, the melt thermal stability deteriorated as throughput was increased, meaning that a greater efficiency was achieved at the detriment of melt consistency. Extruder screw design also had a significant effect on the relationship between energy consumption and melt consistency. Overall, the relationship between the process energy demand and thermal stability seemed to be negatively correlated and also it was shown to be highly complex in nature. Moreover, the level of process understanding achieved here can help to inform selection of equipment and setting of operating conditions to optimise both energy and thermal efficiencies in parallel. / This work was funded through an inter-disciplinary research programme (Grant No. EP/G059330/1) by the EPSRC-UK. The technical assistance provided by Ken Howell, Roy Dixon and John Wyborn is greatly appreciated.
6

Energianalys av byggnad med installerat ångsystem för matlagningsprocesser : Kan ånga vara mer effektivt än el för matlagning?

Bodell, Erik, Åhlander, Simon January 2017 (has links)
Det finns ett stort behov av att minska energianvändningen i världen. Igenom att minska energibehovet så minskar den negativa miljöpåverkan. I en ständigt växande värld där det byggs i allt snabbare takt så ökar också energibehovet. Igenom att effektivisera befintliga byggnader kan energibehovet stagnera eller till och med minska trots utbyggnaden. Igenom att energieffektivisera så kan mer av den energi som används nyttjas istället för att den ska stå för onödiga förluster. Fortifikationsverket har en restaurangbyggnad de anser använder för mycket energi. Denna byggnad innehåller en restaurang som använder ett ångsystem för matproduktion, vilket gör byggnadens energisystem unikt. För att kunna minska byggnadens energianvändning kartläggs och analyseras den i denna rapport. Denna fallstudie genomförs med en litteraturstudie för att utveckla kunskaperna inom området. Sedan utförs mätningar i byggnaden som därefter analyseras och presenteras så att eventuella avvikelser och brister påpekas. Under arbetets gång upptäcktes att en säkring var felinstallerad för mätningen av elanvändningen till en av ångpannorna. Igenom att ha åtgärdat detta för att kunna fakturera rätt så spar Fortifikationsverket nästan 170 000 kr per år som den ångpannan går. Utöver detta så analyserades ångsystemet och uppskattningar gjordes för att kunna svara på om ånga är effektivare än el för matlagning. Det visar sig att ångsystemet kan vara effektivt om stor mängd mat tillagas. Med hänsyn till nätter, helger och de dagar då mindre mat tillagas så är el-utrustning effektivare eftersom att det helt stängs av när det inte används. Till skillnad från ångsystemet som måste täcka upp för förlusterna för att behålla temperatur och tryck, även när systemet inte används. Igenom att byta ut ångsystemet till motsvarande utrustning som drivs av el skulle det gå att spara 205 MWh/år, enligt uppskattningar. Ångsystemet står för 35% av byggnadens totala elanvändning och är den största posten för energianvändningen och är därför den del som fokuserats mest på. Utöver ångsystemet så analyserades övrig energianvändning för att kunna ge förslag på besparingar. Många av förslagen är grundade på vissa uppskattningar och antaganden vilket måste beaktas. Några konkreta exempel på besparingar som kan göras är att sänka inomhustemperaturen för att spara 50 MWh/år, installera tilläggsfönster för att spara upp till 140 MWh/år, installera effektivare kylaggregat – 200 MWh/år, installera bättre styrning till ventilationen – 110 MWh/år, installera bättre styrning till belysning – 40 MWh/år. / There is a great need to reduce energy use in the world. By reducing energy demand, this reduces the negative environmental impact. In a constantly growing world, where it is built at an ever faster pace, the energy demand also increases. By increasing energy efficiency inexisting buildings, energy requirements may stagnate or even decrease despite expansion. By increasing energy efficiency, more of the energy demand can be used instead of standing for energy losses. Fortifikationsverket has a building they believe use too much energy. This building contains a restaurant that uses a steam system to heat its food, which makes the building's energy system unique. In order to reduce the energy consumption of the building, an energy audit is completed and analyzed in this report. This case study is conducted with a literature study to develop the knowledge in the field. Then measurements in the building are performed which are subsequently analyzed and presented to indicate any deviations and deficiencies. During the work it was discovered that a fuse was incorrectly installed to measure the electricity consumption of one of the boilers. By correcting this in order to be able to bill correctly, Fortifikationsverket saves almost 170,000 SEK per year as the boiler goes. In addition to this, the steam system was analyzed and estimates were made to respond if steam is more effective than electricity for cooking. It turns out that the steam system can be effective if a large amount of food is cooked. Considering nights, weekends and days when less food is cooked, electrical equipment is more effective because it completely turns off when not in use. Unlike the steam system that has to cover the energy losses to keep temperature and pressure, even when the system is not in use. By replacing the steam system with equivalent electrical equipment, it couldsave 205 MWh/year, according to estimates.The steam system accounts for 35% of the building's total electricity demandand is the largest item for energy use and is therefore the most focused area. In addition to the steam system, other energy usage was analyzed to provide energy savings. Many of the proposals are based on certain estimates and assumptions which must be considered. Some examples of savings that can be made is lowering the indoor temperature to save 50 MWh/year, install additional windows to save up to 140 MWh/year, install more efficient cooling units -200 MWh/year, install better ventilation control systems-50 MWh/year, install better controls for indoor lighting -40 MWh/year.
7

Performance analysis of <em>m</em>MCSK-<em>m</em>MFSK modulation variants with comparative discussion

Pouttu, A. (Ari) 23 November 2012 (has links)
Abstract This thesis deals with the fascinating subject of the design of digital communication systems - or more precisely one topic therein, i.e., modulation. Modulation and its counterpart demodulation are the means of making the information ride the beast of a wireless radio channel. The introduction of mMFSK and amMFSK generated ideas of applying the approach to other modulation methods. The straightforward extension was to apply the method to CSK modulation to introduce mMCSK modulation. The analysis shows that due to the orthogonality of the signaling waveforms of mMCSK (with Walsh codes) and mMFSK, the same performance is achieved for modulation methods with the same modulation alphabet. But with CSK it is rather easy to construct non-orthogonal signaling waveforms. Hence, the thesis also gives analytical results for non-orthogonal mMCSK and especially considers (as an example) the use of Gold and Kasami codes. The results indicate that the best choice of codes for a non-coherent mMCSK system is the orthogonal code family, which is a rather intuitive result. However, for a coherent mMCSK system, better performance could be achieved with non-orthogonal codes. Given that we can construct a code set where the cross-correlation between the codes in the family is negative (&#961;i,j&#60;0), performance improvement compared to the orthogonal code family is achieved. The results show that, for instance, a 0.5 dB performance improvement in the AWGN channel can be achieved by using a specifically constructed set of Kasami codes as the basis functions in the modulation. The thesis also presents the performance analysis results of mMCSK in a flat Rayleigh fading channel. To further enlarge the modulation alphabet sizes (with the price of larger spectrum usage) it was realized that combining the mMFSK and mMCSK would be an interesting choice. The mMCSK-mMFSK modulation was hence introduced, which can be viewed as the main contribution of this thesis. A method to analyze this two-component modulation was developed and the performance analyses give results for mMCSK-mMFSK modulation in AWGN and flat Rayleigh fading channels for both coherent and non-coherent receivers. The performance was also assessed with orthogonal and non-orthogonal code constructs. Moreover, an antipodal extension of the mMCSK-mMFSK modulation was introduced with the analysis of the performance. A third contribution of the thesis was to introduce the mPPM modulation method following the mMFSK principles. The performance results obtained in the mMCSK can also be applied to these modulation formats in certain scenarios. PPM modulation has been widely suggested to be used in UWB systems. In UWB systems, the means to adapt the data rate is the use of pulse repetition. Hence, the performance analysis of the mPPM modulation methods with pulse repetition and a non-coherent receiver was computed. The performance of pulse repetition in impulsive interference was also computed. / Tiivistelmä Tässä väitöskirjatyössä tarkastellaan tietoliikennejärjestelmän suunnitteluun liittyvää osa-aluetta modulaatiomenetelmä. Modulaatio ja sen vastinpari demodulaatio ovat mekanismit, joiden avulla siirrettävä tieto saatetaan muotoon, jolla se voidaan siirtää radiokanavassa. mMFSK ja amMFSK modulaatiomenetelmien kehittäminen loi pohjan, jota lähdettiin soveltamaan myös muihin modulaatiotekniikoihin. Suoritetut matemaattiset analyysit osoittavat, että samalle modulaatioaakkoston koolle mMCSK (käyttäen Walsh-koodeja) ja mMFSK saavuttavat saman suorituskyvyn olettaen modulaatioiden olevan ortogonaalisia. CSK-tekniikalla on kuitenkin helppo rakentaa koodeja, jotka ovat epäortogonaalisia. Väitöskirjassa analysoidaan myös muutamia tapauksia epaortogonaaliselle mMCSK:lle, jossa esimerkinomaisesti tarkastellaan Gold- ja Kasami-koodien käyttöä. Tulokset osoittavat, että epäkoherentille mMCSK:lle paras valinta koodiperheeksi on ortogonaalinen koodiperhe, joka tuloksena on myös intuitiivinen. Koherentille mMCSK:lle voidaan kuitenkin rakentaa epäortogonaalisia koodikonstruktioita, joissa koodien välinen ristikorrelaatio on negatiivinen ja tällöin saavutetaan suorituskyvyn parantumista ortogonaaliseen koodiperheeseen verattuna. Tulokset Gold- ja Kasami-koodeille AWGN-kanavassa osoittavat, että n. 0.5 dB suorituskyvyn paraneminen on saavutettavissa. Työssä johdetaan myös analyyttiset tulokset vastaaville tapauksille Rayleigh-häipyvässä kanavassa. Tutkittaessa mMCSK- ja mMFSK-modulaatioita, huomattiin, että yhdistämällä nämä kaksi voidaan saavuttaa erittäin suuria modulaatioaakkostoja. Hintana on suurempi spektrin käyttö. mMCSK-mMFSK-modulaation kehittämistä voidaan pitää tämän työn päätuloksena. Työssä kehitetään likimääräinen menetelmä tämän kaksi-komponenttisen modulaation suorituskyvyn analysoimiseksi. Tuloksina esitetään modulaatiomenetelmän suorituskyky sekä AWGN- että Rayleigh-häipyvässä kanavassa. Suorituskykytuloksia esitetään myös epäortogonaalisille koodikonstruktioille. Lisäksi kehitettiin antipodaalinen laajennus mMCSK-mMFSK-modulaatiosta ja suoritettiin suorituskykyanalyysi AWGN-kanavassa. Työn kolmantena tuloksena esitetään mPPM-modulaatiomenetelmä hyödyntäen mMCSK-modulaation periaatteita. mMCSK-suorituskykyanalyysia voidaan tietyin ehdoin soveltaa myös näihin modulaatiomenetelmiin, joiden käyttöä esitetään usein ultralaajakaistajärjestelmissä (UWB). UWB-järjestelmissä datanopeutta säädetään usein pulssin toistoa käyttämällä. Työssä johdetaan suorityskykytulokset epäkoherentille mPPM-vastaanottimelle myös pulssintoiston yhteydessä. Lisäksi johdettiin suorituskykylausekkeet ko. modulaatioille impulsiivisen häiriön läsnäollessa.
8

Pathways to servers of the future

Lehner, Wolfgang, Nagel, Wolfgang, Fettweis, Gerhard 11 January 2023 (has links)
The Special Session on “Pathways to Servers of the Future” outlines a new research program set up at Technische Universität Dresden addressing the increasing energy demand of global internet usage and the resulting ecological impact of it. The program pursues a novel holistic approach that considers hardware as well as software adaptivity to significantly increase energy efficiency, while suitably addressing application demands. The session presents the research challenges and industry perspective.

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