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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Comparison of Abr Recordings from Tympanic-Membrane and Ear-Canal Electrode

Murnane, Owen D., Parent, T. 01 January 1995 (has links)
No description available.
32

Etude de l’encodage des sons de parole par le tronc cérébral dans le bruit / Study of brainstem speech in noise processing

Richard, Céline 17 December 2010 (has links)
Ce travail s’est intéressé au traitement sous cortical de la parole dégradée par le bruit, notamment par la caractérisation première de l’importance de certains traits acoustiques dans la perception de la parole normale. Pour cela, nous avons d’abord participé à la mise au point de la technique électrophysiologique de potentiels évoqués auditifs obtenus en réponse à des sons de parole, technique proche de celle des potentiels évoqués auditifs précoces, mais qui a des exigences propres en matière de traitement du signal et de techniques de recueil, qui nécessitent une adaptation importante de part la nature différente des stimuli français par rapport aux stimuli anglais utilisés par l’équipe de référence américaine. Les différents axes de notre recherche ont, par ailleurs, permis de mettre en évidence l’importance de l’encodage sous cortical de certaines caractéristiques acoustiques telles que l’enveloppe temporelle, le voisement, mettant par là même en évidence un possible effet corticofuge sur l’encodage de celui-ci. Ces différentes expériences nous ont amenés à nous poser la question des conditions idéales de recueil des PEASP, et notamment l’effet de l’intensité sur le recueil de ceux-ci, mettant en évidence une relation non-linéaire entre l’intensité de stimulation, et les caractéristiques des PEAPSP. Si une intensité de 20 dB SL semble nécessaire au recueil d’un PEAPSP, les réponses montrent une variabilité qui reste très grande à l’échelon individuel, ce qui rend l’utilisation de l’outil PEAPSP à visée diagnostique, que ce soit dans les troubles du langage chez l’enfant, ou dans les troubles de l’audition dans le bruit, difficile. / The major purpose of my thesis was the investigation of brainstem structures implications into speech in noise processing, particularly by identifying the impact of acoustic cues on normal speech perception. Firstly, we were involved in the engineering of the speech auditory brainstem responses (SABR) recording system. SABR are similar to brainstem auditory evoked responses to clicks, but require different acquisition and signal processing set-ups, due to the difference between the French and the American stimuli used by the American reference team. The different studies presented here, permitted to emphasize the role of brainstem structures into the subcortical processing of acoustical cues, such as the temporal enveloppe, or the voicing, with a possible evidence of a corticofugal effect on SABR. These experimentations lead us to a more fundamental question on the best conditions required for PEASP collection, in particular, the best stimulation intensity needed. The results of the experiment on intensity effect showed a non linear relation between the stimulation intensity and PEASP characteristics. Even if an intensity of only 20 dB SL seems enough for SABR recording, individual results are still highly variable so that diagnostic application of SABR on, for example, children with language learning problems or subject suffering from speech in noise perception impairment remains difficult.
33

Tratamento de efluente de laticínio em reator anaeróbio compartimentado / Anaerobic treatment of dairy wastewater in an anaerobic baffled reactor

Carla Cristina (Lucas Kyem) Araújo dos Santos 13 June 2016 (has links)
Os efluentes com elevadas concentrações de lipídios, apesar de demonstrarem elevado potencial para produção de metano podem causar inibição da atividade do consórcio anaeróbio, impossibilitando a produção de biogás. O presente trabalho teve como objetivo o estudo de um reator anaeróbio compartimentado (ABR) com cinco compartimentos tratando efluente simulado de laticínio. Para tanto, a biomassa, foi adaptada por 51 dias e em seguida submetida a tempos de detenção de hidráulica (TDH) de 72h, 24h e 12h, tendo o monitoramento se estendido por 340 dias. Enquanto operando com TDH de 24, o sistema foi submetido a choques hidráulicos e de carga orgânica através da diminuição do TDH para 12 h. O reator absorveu bem a carga, e em 36 horas recuperou os valores prévios de eficiência. Quando operou permanentemente com 12 horas, todavia, problemas de flotação de biomassa e obstruções foram constantes. As eficiências de remoção de matéria orgânica alcançadas para cada condição aplicada foram de 92 ± 3,0; 91 ± 1,8 e 90 ± 2,4% para os TDH de 72h, 24h e 12h, respectivamente. Esses valores foram estatisticamente semelhantes (Anova e L-Fisher). A percentagem de metano no biogás aumentou com a redução de TDH, tendo sido 41 ± 23, 53 ± 27 e 62 ± 12% quando os TDH foram 72, 24 e 12 horas, respectivamente. A produção média de alcalinidade foi de 320±25 mg.CaCO3.L-1, sendo esta observada desde o início da operação. A relação média entre alcalinidade intermediária e parcial foi de 0.1±0.06 em amostras coletadas na saída do sistema. Embora apresentando problemas de obstrução com o menor TDH, o ABR foi eficiente, robusto e confiável ao tratar efluente de laticínios, tendo produzido um efluente líquido de alta qualidade e biogás rico em metano. / Effluents with high concentrations of lipids, although demonstrating high potential for methane production represents potential inhibition of the anaerobic consortium activity, depleting the production of biogas. This project was carried out monitoring an anaerobic hybrid baffled reactor with five compartments (ABR) treating simulated dairy wastewater. The biomass, was adapted for 51 days and then subjected to hydraulic retention times (HDT) of 72h, 24h and 12h, resulting in a monitoring period of 340 days. While operating with 24h of HRT, the system was subjected to three organic and hydraulic shock loads, when its HDT was decreased to 12 h. The reactor absorbed the shock within 36 hours, achieving similar efficiencies to the previous condition. Nevertheless, although presenting high organic matter efficiencies, when permanently operating with HDT of 12 h, clogging problems due to biomass flotation were constant. The organic matter removal efficiencies for each operational condition were 92 ± 3%, 91 ± 1.8%, 90 ± 2,4%. Those values were statistically similar. The methane percentage in the biogas increased with the HDT reduction, being 41 ± 23, 53 ± 27, and 62 ± 12% when the HDT were 72, 24 and 12 hours. Alkalinity production was observed since the beginning of operation. The mean relation between intermediate and partial alkalinity was 0.1±0.006 in samples collected in the system output. Although presenting clogging problems with the smallest HDT, the ABR was efficient, robust and reliable when treating dairy effluents, producing a high quality liquid effluent and a methane rich biogas.
34

Avaliação do tratamento combinado de lixiviado de aterro sanitário e esgoto sanitário em sistema de lodos ativados / Evaluation of the combined treatment of landfill leachate and domestic sewage in activated sludge system

Edilincon Martins de Albuquerque 05 June 2012 (has links)
Um dos principais resíduos gerados nos aterros é o lixiviado, que possui elevada concentração de matéria orgânica biodegradável e refratária e de matéria inorgânica, como nitrogênio amoniacal e metais pesados. O tratamento combinado de lixiviado com esgoto sanitário tem sido utilizado em algumas estações de tratamento de esgoto (ETE) brasileiras. No entanto, o processo ainda sofre vários questionamentos e incertezas, especialmente sobre os efeitos da adição do lixiviado sobre o sistema de tratamento. Nesse contexto, o presente trabalho visou avaliar a eficiência do tratamento combinado de lixiviado/esgoto em sistema de lodos ativados, em diferentes condições. Na primeira etapa desta pesquisa, foram realizados experimentos de tratabilidade em escala de bancada (regime de batelada) utilizando as proporções volumétricas de 0% (controle), 0,2%, 2% e 5% de lixiviado em diferentes condições experimentais. Dentre eles, o Experimento 2 (lixiviado pré-tratado por alcalinização e air stripping) se mostrou mais viável tecnicamente, alcançando eficiências de remoção da DBO, da DQO e do COD acima de 97, 82, 60%, respectivamente, até a proporção de 2% de lixiviado pré-tratado. Na segunda etapa da pesquisa, foi avaliada a tratabilidade utilizando reatores em escala piloto (regime contínuo) tratando esgoto sanitário com 2% (P1) e 0% (P2-controle) de lixiviado pré-tratado, com relação microrganismo-alimento de 0,22 kgDBO/kgSSV.dia, tempo de detenção hidráulica de 24 horas e idade do lodo de 20 dias. Os resultados indicaram viabilidade do tratamento nas condições estudadas com 2% de lixiviado pré-tratado, cujas eficiências médias de remoção da DBO, da DQO, do COD foram de 93, 84 e 60%, respectivamente. Esta pesquisa foi desenvolvida com apoio financeiro (Processo N° 2010/51955-2) da Fundação de Amparo à Pesquisa de São Paulo (FAPESP). / The leachate is one of the main wastes generated in landfills, it has a high concentration of biodegradable and refractory organic matter and inorganic matter, such as ammonia and heavy metals. The combined treatment of leachate with sewage has been used in various sewage treatment plants in Brazil. However, there are still many questions and uncertainties about the process, especially the effects of adding leachate on the treatment system. In this context, this study aimed at evaluating the efficiency of combined treatment of leachate/sewage in activated sludge under different conditions. In the first stage of this research, treatability experiments were carried out in a bench scale (SBR) using the volumetric proportions of 0% (control), 0.2%, 2% and 5% leachate under different experimental conditions. The Experiment 2 (leachate pretreated by alkalinization and air stripping) was more technically feasible, achieving efficiencies of removal of BOD, COD and DOC above 97, 82, 60%, respectively, until the proportion of 2% pre-treated leachate. In the second stage of the research was evaluated the treatability using pilot-scale reactors (continuous flow) for sewage treatment with 2% (P1) and 0% (P2-control) leachate pretreated. The operational parameters adopted were food-microorganism rate of 0.22 kgDBO/ kgSSV.d, hydraulic retention time of 24 hours and the sludge retention time of 20 days. The results indicated the viability of the combined treatment with 2% leached pretreated, whose average efficiency of removing BOD, COD, DOC were 93, 84 and 60% respectively. This research was developed with financial support (case No. 2010/2-51955) of Fundação de Amparo à Pesquisa de São Paulo (FAPESP).
35

AN EVALUATION OF SDN AND NFV SUPPORT FOR PARALLEL, ALTERNATIVE PROTOCOL STACK OPERATIONS IN FUTURE INTERNETS

Suresh, Bhushan 09 July 2018 (has links)
Virtualization on top of high-performance servers has enabled the virtualization of network functions like caching, deep packet inspection, etc. Such Network Function Virtualization (NFV) is used to dynamically adapt to changes in network traffic and application popularity. We demonstrate how the combination of Software Defined Networking (SDN) and NFV can support the parallel operation of different Internet architectures on top of the same physical hardware. We introduce our architecture for this approach in an actual test setup, using CloudLab resources. We start of our evaluation in a small setup where we evaluate the feasibility of the SDN and NFV architecture and incrementally increase the complexity of the setup to run a live video streaming application. We use two vastly different protocol stacks, namely TCP/IP and NDN to demonstrate the capability of our approach. The evaluation of our approach shows that it introduces a new level of flexibility when it comes to operation of different Internet architectures on top of the same physical network and with this flexibility provides the ability to switch between the two protocol stacks depending on the application.
36

Journaling in Search of the Neurodivergent Self: An Arts-based Research Project Dialoguing with Kurt Cobains Journals

Attias, Michelle D. 28 September 2021 (has links)
No description available.
37

The effect of COVID-19 pandemic on the stock of three antibiotics in healthcare facilities in Uganda: a prospective cohort study

Ventura-Gabarró, Cèlia January 2022 (has links)
Background There has been an increase in antibiotic consumption in the last decades in lower income countries, still, it is insufficient to meet everyone’s needs. Ensuring access to them is essential to lower the burden of disease and mortality, as well as to accomplish the Sustainable Developmental Goals. However, this consumption needs to be responsible to avoid faster spreading of antibiotic resistances. The recent COVID-19 pandemic has threatened the healthcare systems everywhere, both directly and indirectly. Nevertheless, there is a lack of research on how it has impacted antibiotics’ stock.  Methods This study used secondary data of a cross-sectional cohort design to follow the impact of the pandemic on the stock of three commonly used antibiotics in healthcare facilities of Uganda. The data was compared between three time periods: before the pandemic started (January 2019-February 2020), during the first months of the pandemic and coinciding with the harshest restrictions (March 2020-May 2020), and the second period of the pandemic (June 2020-December 2020). Results An increase in stock of the antibiotics was observed as the restrictions hardened, followed by a decrease when they were lifted. Likewise, this rise happened both in the consumption and arrival of antibiotics. Stratified analysis was preformed grouping by healthcare level and by region, seeing that the strongest change happened in facilities at level II and III in the Eastern region of Uganda. Conclusions  This suggests that the pandemic influenced the antibiotics stocks and consumption. Further research needs to be done to better understand this effect.
38

Möglichkeiten zur Behandlung saisonal anfallender Abwässer in ländlich strukturierten Gebieten durch Anpassung der Bemessungsgrundlagen und temporäre Aktivierung interner Reserven

Schalk, Thomas 13 November 2017 (has links) (PDF)
Vor dem Hintergrund saisonaler Einflussfaktoren stellen ländlich strukturierte Gebiete besondere Anforderungen an Bemessung und Betrieb von Kläranlagen. Tourismus bildet neben landwirtschaftlich bedingten Ernte- und Verarbeitungskampagnen den bedeutendsten Faktor für saisonale Belastungsschwankungen. Da der größte Teil der Fremdenverkehrseinrichtungen über weniger als 100 Übernachtungsplätze verfügt, besteht bei fehlendem Kanalanschluss ein entsprechender Bedarf an Klein- und Kleinen Kläranlagen zur Behandlung der anfallenden Abwässer. Die Bemessung von Kläranlagen der Größenklasse 1 wird bei fehlenden Messwerten auf Grundlage der im ATV-DVWK-A 198 (2003) als 85-%-Perzentil angegebenen einwohnerspezifischen Frachten durchgeführt. Abwasser aus einfachen Fremdenverkehrseinrichtungen wie Campingplätzen und Hütten weist im Vergleich zur üblichen kommunalen Abwasserzusammensetzung bezogen auf CSB und BSB5 höhere Anteile an Stickstoff- und Phosphorverbindungen auf. Die spezifischen Stickstofffrachten liegen i. M. bei 10 – 11 g/P/d, die spezifischen CSB-Frachten bei i. M. 52 – 68 g/P/d. Die tatsächlichen Frachten werden von der Ausstattung (Restaurant, Wäscherei, etc.) der jeweiligen Unterkunft beeinflusst und sind in der Bemessung gesondert zu berücksichtigen. Für die Behandlung saisonal anfallender Abwässer eignen sich Verfahren mit großem vorgeschaltetem Puffervolumen oder Anlagen mit großem internem Puffer, wie z. B. Bodenfilteranlagen. Anaerobe Vorbehandlungsanlagen wie Anaerobic Baffled Reactors (ABR) können bei entsprechenden Temperaturen zur Frachtentlastung nachgeschalteter aerober Stufen beitragen. Unter gemäßigten Klimabedingungen werden inklusive Sedimentationsprozessen in Vorklärbecken i. M. 50 % des zugeführten CSB eliminiert. Aufgrund der starken Temperaturabhängigkeit des CSB-Abbaus, der Dauer des Einfahrbetriebs, der Empfindlichkeit gegenüber zu hohem Schlammabzug und des nicht berechenbaren Feststoffabtriebs ist unter gemäßigten Klimabedingungen und ohne technische Weiterentwicklung des Verfahrens keine über den Wirkungsgrad von Absetzanlagen hinausgehende Eliminationsleistung bei der Bemessung kalkulierbar. Für saisonal belastete Bodenfilter stellt die Abminderung des Flächenbedarfs bzw. die Steigerung der CSB-Flächenbelastung analog zum nicht belasteten Zeitraum eine betriebssichere und wirtschaftliche Lösung dar, bei der die Einhaltung der Mindestanforderungen gewährleistet ist. Bei geforderter Nitrifikation ist aufgrund des hohen TKN-Konzentrationsniveaus im Abwasser aus Fremdenverkehrseinrichtungen ein Wirkungsgrad von > 95 % für die TKN-Elimination erforderlich. Im Abwasser enthaltene Hemmstoffe, insbesondere in Vorkläranlagen gebildetes Sulfid, können die Nitrifikation beeinträchtigen. Dabei werden Ammoniumoxidation und Nitritoxidation gehemmt. Charakteristisch sind hohe NH4-N- und NO2-N-Konzentrationen im Ablauf (Extremwerte bis zu 55 mg NO2-N/l). Während sich Nitritoxidierer über mehrere Jahre an dauerhaft hohe Sulfidkonzentrationen adaptieren können, wird die Ammoniumoxidation direkt über die Sulfidkonzentration beeinflusst. / In rural communities seasonal factors complicate design and operation of wastewater treatment plants. Tourism as well as agricultural harvesting and processing campaigns are the major causes for seasonal load variations. Due to the fact that accommodation capacities in rural tourism industry rarely exceed 100 beds small sewage treatment plants are acquired if a connection to a sewer system is not feasible. Small wastewater treatment plants can be designed using the population equivalents (PE). According to the German Water Association spreadsheet ATV-DVWK-A 198, PEs are defined as the 85-%-percentile input load. Wastewater of basic accommodations like camping sites and lodges contains higher levels of nitrogen and phosphorous compounds than 'standard' domestic wastewater. The mean specific nitrogen loads reach 10 – 11 g/guest/d, the mean specific COD-load 52 – 68 g/guest/d. The special amenities of vacation homes (restaurant, laundry) affect the real loads and have to be considered in dimensioning. Regarding the treatment of seasonal wastewater, processes with large upstream buffer or large internal buffer, such as constructed wetlands, are suitable. Furthermore, at moderate temperatures anaerobic pretreatment devices, like anaerobic baffled reactors (ABR), can reduce the input load to aerobic post treatment stages. An approximate COD elimination of 50 % can be expected by anaerobic degradation and sedimentation in the ABR in combination with upstream primary clarifiers at around 20 °C. Due to the strong temperature dependence, the long start-up-period, the sensitivity towards fail-desludging, the generation of immediate oxygen demand at low temperatures as well as unpredictable sludge overflow events, it does not seem justified to calculate higher design elimination efficiencies for ABRs than for sedimentation tanks. The design of subsurface vertical flow constructed wetlands with seasonally induced high loading periods are approved for the elimination of organic substances. This accepted assumption was confirmed for the plant under investigation operated at a mean COD-load of 20 g/m²/d, not exceeding the effluent control values for COD in six years. In contrast, oxidation of ammonia and nitrite were inhibited by high sulfide levels (mean sulfide concentration: 48 ± 26 mg/L). Nitrite accumulation reached its peak value at 55 mg NO2-N/L and decreased within 4 years below 1 mg/L due to the adaption of nitrite-oxidizing microorganisms.
39

Möglichkeiten zur Behandlung saisonal anfallender Abwässer in ländlich strukturierten Gebieten durch Anpassung der Bemessungsgrundlagen und temporäre Aktivierung interner Reserven

Schalk, Thomas 05 July 2017 (has links)
Vor dem Hintergrund saisonaler Einflussfaktoren stellen ländlich strukturierte Gebiete besondere Anforderungen an Bemessung und Betrieb von Kläranlagen. Tourismus bildet neben landwirtschaftlich bedingten Ernte- und Verarbeitungskampagnen den bedeutendsten Faktor für saisonale Belastungsschwankungen. Da der größte Teil der Fremdenverkehrseinrichtungen über weniger als 100 Übernachtungsplätze verfügt, besteht bei fehlendem Kanalanschluss ein entsprechender Bedarf an Klein- und Kleinen Kläranlagen zur Behandlung der anfallenden Abwässer. Die Bemessung von Kläranlagen der Größenklasse 1 wird bei fehlenden Messwerten auf Grundlage der im ATV-DVWK-A 198 (2003) als 85-%-Perzentil angegebenen einwohnerspezifischen Frachten durchgeführt. Abwasser aus einfachen Fremdenverkehrseinrichtungen wie Campingplätzen und Hütten weist im Vergleich zur üblichen kommunalen Abwasserzusammensetzung bezogen auf CSB und BSB5 höhere Anteile an Stickstoff- und Phosphorverbindungen auf. Die spezifischen Stickstofffrachten liegen i. M. bei 10 – 11 g/P/d, die spezifischen CSB-Frachten bei i. M. 52 – 68 g/P/d. Die tatsächlichen Frachten werden von der Ausstattung (Restaurant, Wäscherei, etc.) der jeweiligen Unterkunft beeinflusst und sind in der Bemessung gesondert zu berücksichtigen. Für die Behandlung saisonal anfallender Abwässer eignen sich Verfahren mit großem vorgeschaltetem Puffervolumen oder Anlagen mit großem internem Puffer, wie z. B. Bodenfilteranlagen. Anaerobe Vorbehandlungsanlagen wie Anaerobic Baffled Reactors (ABR) können bei entsprechenden Temperaturen zur Frachtentlastung nachgeschalteter aerober Stufen beitragen. Unter gemäßigten Klimabedingungen werden inklusive Sedimentationsprozessen in Vorklärbecken i. M. 50 % des zugeführten CSB eliminiert. Aufgrund der starken Temperaturabhängigkeit des CSB-Abbaus, der Dauer des Einfahrbetriebs, der Empfindlichkeit gegenüber zu hohem Schlammabzug und des nicht berechenbaren Feststoffabtriebs ist unter gemäßigten Klimabedingungen und ohne technische Weiterentwicklung des Verfahrens keine über den Wirkungsgrad von Absetzanlagen hinausgehende Eliminationsleistung bei der Bemessung kalkulierbar. Für saisonal belastete Bodenfilter stellt die Abminderung des Flächenbedarfs bzw. die Steigerung der CSB-Flächenbelastung analog zum nicht belasteten Zeitraum eine betriebssichere und wirtschaftliche Lösung dar, bei der die Einhaltung der Mindestanforderungen gewährleistet ist. Bei geforderter Nitrifikation ist aufgrund des hohen TKN-Konzentrationsniveaus im Abwasser aus Fremdenverkehrseinrichtungen ein Wirkungsgrad von > 95 % für die TKN-Elimination erforderlich. Im Abwasser enthaltene Hemmstoffe, insbesondere in Vorkläranlagen gebildetes Sulfid, können die Nitrifikation beeinträchtigen. Dabei werden Ammoniumoxidation und Nitritoxidation gehemmt. Charakteristisch sind hohe NH4-N- und NO2-N-Konzentrationen im Ablauf (Extremwerte bis zu 55 mg NO2-N/l). Während sich Nitritoxidierer über mehrere Jahre an dauerhaft hohe Sulfidkonzentrationen adaptieren können, wird die Ammoniumoxidation direkt über die Sulfidkonzentration beeinflusst. / In rural communities seasonal factors complicate design and operation of wastewater treatment plants. Tourism as well as agricultural harvesting and processing campaigns are the major causes for seasonal load variations. Due to the fact that accommodation capacities in rural tourism industry rarely exceed 100 beds small sewage treatment plants are acquired if a connection to a sewer system is not feasible. Small wastewater treatment plants can be designed using the population equivalents (PE). According to the German Water Association spreadsheet ATV-DVWK-A 198, PEs are defined as the 85-%-percentile input load. Wastewater of basic accommodations like camping sites and lodges contains higher levels of nitrogen and phosphorous compounds than 'standard' domestic wastewater. The mean specific nitrogen loads reach 10 – 11 g/guest/d, the mean specific COD-load 52 – 68 g/guest/d. The special amenities of vacation homes (restaurant, laundry) affect the real loads and have to be considered in dimensioning. Regarding the treatment of seasonal wastewater, processes with large upstream buffer or large internal buffer, such as constructed wetlands, are suitable. Furthermore, at moderate temperatures anaerobic pretreatment devices, like anaerobic baffled reactors (ABR), can reduce the input load to aerobic post treatment stages. An approximate COD elimination of 50 % can be expected by anaerobic degradation and sedimentation in the ABR in combination with upstream primary clarifiers at around 20 °C. Due to the strong temperature dependence, the long start-up-period, the sensitivity towards fail-desludging, the generation of immediate oxygen demand at low temperatures as well as unpredictable sludge overflow events, it does not seem justified to calculate higher design elimination efficiencies for ABRs than for sedimentation tanks. The design of subsurface vertical flow constructed wetlands with seasonally induced high loading periods are approved for the elimination of organic substances. This accepted assumption was confirmed for the plant under investigation operated at a mean COD-load of 20 g/m²/d, not exceeding the effluent control values for COD in six years. In contrast, oxidation of ammonia and nitrite were inhibited by high sulfide levels (mean sulfide concentration: 48 ± 26 mg/L). Nitrite accumulation reached its peak value at 55 mg NO2-N/L and decreased within 4 years below 1 mg/L due to the adaption of nitrite-oxidizing microorganisms.
40

A Performance Analysis of TCP and STP Implementations and Proposals for New QoS Classes for TCP/IP

Holl, David J. 01 May 2003 (has links)
With a new United States Army initiative to exploit commercially developed information technology, there is a heightened interest in using Internet protocols over the military's geosynchronous satellite links. TCP is the dominant Internet protocol used for reliable data exchange, but its own design limits performance when used over long delay network links such as satellites. Initially this research set out to compare TCP with another proposed protocol, the Satellite Transport Protocol (STP). However through a series of tests, we found that STP does not fulfill its claims of increased throughput over TCP and uncovered a flaw in STP's founding research. In addition, this thesis proposes and demonstrates novel performance enhancing techniques that significantly improve transport protocol throughput.

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