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Sieger, Philipp. "The Financing of MBOs and MBIs in Family-owned SME a Roadmap for Potential Buyers /." St. Gallen, 2007. http://www.biblio.unisg.ch/org/biblio/edoc.nsf/wwwDisplayIdentifier/02606853002/$FILE/02606853002.pdf.
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Anderson, Christopher. "BANDWIDTH LIMITED 320 MBPS TRANSMITTER." International Foundation for Telemetering, 1996. http://hdl.handle.net/10150/607635.
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International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, CaliforniaWith every new spacecraft that is designed comes a greater density of information that will be stored once it is in operation. This, coupled with the desire to reduce the number of ground stations needed to download this information from the spacecraft, places new requirements on telemetry transmitters. These new transmitters must be capable of data rates of 320 Mbps and beyond. Although the necessary bandwidth is available for some non-bandwidth-limited transmissions in Ka-Band and above, many systems will continue to rely on more narrow allocations down to X-Band. These systems will require filtering of the modulation to meet spectral limits. The usual requirements of this filtering also include that it not introduce high levels of inter-symbol interference (ISI) to the transmission. These constraints have been addressed at CE by implementing a DSP technique that pre-filters a QPSK symbol set to achieve bandwidth-limited 320 Mbps operation. This implementation operates within the speed range of the radiation-hardened digital technologies that are currently available and consumes less power than the traditional high-speed FIR techniques.
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Bishop, Jim, and John Welch. "800 Mbps TELEMETRY PROCESSING SYSTEM." International Foundation for Telemetering, 2000. http://hdl.handle.net/10150/607707.
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International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, CaliforniaSatellites are becoming more capable and complex, as such their downlink requirements are increasing. In addition, future satellite systems will be operating at Ka-band that provides ample bandwidth to support the increase in downlink rates up to 800 Mbps. This paper describes a new generation commercial solution that can support 800 Mbps telemetry processing for data reception, frame synchronization, time tagging, Reed-Solomon forward error correction, data routing, data storage, data playback for testing, networking, and Bit Error Rate (BER) Testing.
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Genrich, Thad J. "300 MBPS CCSDS Processing Using FPGA's." International Foundation for Telemetering, 1996. http://hdl.handle.net/10150/611415.
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International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, CaliforniaThis paper describes a 300 Mega Bit Per Second (MBPS) Front End Processor (FEP) prototype completed in early 1993. The FEP implements a patent pending parallel frame synchronizer (frame sync) design in 12 Actel 1240 Field Programmable Gate Arrays (FPGA's). The FEP also provides (255,223) Reed-Solomon (RS) decoding and a High Performance Parallel Interface (HIPPI) output interface. The recent introduction of large RAM based FPGA's allows greater high speed data processing integration and flexibility to be achieved. A proposed FEP implementation based on Altera 10K50 FPGA's is described. This design can be implemented on a single slot 6U VME module, and includes a PCI Mezzanine Card (PMC) for a commercial Fibre Channel or Asynchronous Transfer Mode (ATM) output interface module. Concepts for implementation of (255,223) RS and Landsat 7 Bose-Chaudhuri-Hocquenghem (BCH) decoding in FPGA's are also presented. The paper concludes with a summary of the advantages of high speed data processing in FPGA's over Application Specific Integrated Circuit (ASIC) based approaches. Other potential data processing applications are also discussed.
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Castellano, Pedro. "¿Deberían aprender a investigar los MBAs?" Universidad Peruana de Ciencias Aplicadas (UPC), 2013. http://hdl.handle.net/10757/285445.
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Últimamente se ha reavivado el debate respecto a la conveniencia o inconveniencia de incluir en el programa MBA el tema de investigación y la exigencia de la presentación de una tesis para obtener el grado de maestría en administración.
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Sivawamy, Ravichandran, and Geethanjali Soundappan. "File-Based Delivery over LTE-Based MBMS." Thesis, Blekinge Tekniska Högskola, Sektionen för ingenjörsvetenskap, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-2914.
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One of the most important emerging aspects of Third Generation Partnership Project (3GPP) is the Multimedia Broadcast/Multicast Service (MBMS) aiming to deliver multimedia contents to mobile users more efficiently in point-to-multipoint way. 3GPP also recommends an Application Layer Forward Error Correction (AL-FEC) scheme, especially for MBMS, in order to provide reliable transmission over mobile networks. Due to many emerging FEC schemes, the existing 3GPP standardized systematic fountain Raptor code FEC scheme is considered to be outdated. One of the newly emerged codes, namely RaptorQ, has enhanced an AL-FEC scheme by providing higher protection against packet loss and superior flexibility to meet the growing demand in mobile multicast services. In this work, we provide an extensive device based performance evaluation of RaptorQ FEC codes, specified as RFC 6330 in Internet Engineering Task Force (IETF), and notice that the performance always outperforms that of the existing Raptor (RFC 5053) codes in terms of decoding speed, latency and memory. We also include the device based performance comparison of RaptorQ FEC codes in a comparison with other FEC schemes like Supercharged codes and Reed Solomon + Low Density Parity Check codes (RS+ LDPC). Finally, we conduct simulation carried out in the mobile devices for several network parameters like latency, decoding speed and memory in combination with FEC encoding and decoding parameters and investigate that RaptorQ is the best code that suits multicast services.+46723185198, +4917626686238,+4915166808450
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Wunderlich, Kristin, Jim Chesney, and Toby Bennett. "Frame Synchronization At 300 Mbps And Beyond." International Foundation for Telemetering, 1990. http://hdl.handle.net/10150/613474.
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International Telemetering Conference Proceedings / October 29-November 02, 1990 / Riviera Hotel and Convention Center, Las Vegas, NevadaWhile most current ground based space telemetry acquisition systems are designed for and support data rates up to a few megabits per second (Mbps), NASA’s Tracking and Data Relay Satellite System (TDRSS) can support downlink rates up to 300 Mbps. In addition, the Advanced TDRSS (ATDRSS) is expected to support rates up to 650 Mbps. These high data rates will be required to support NASA’s future large scale operational programs such as the Space Station Freedom and the Earth Observation System. At the Goddard Space Flight Center, a prototype Frame Synchronizer card is under development which will operate at a minimum of 300 Mbps while providing a full suite of programmable functions such as 32 bit correlation, search-check-lock strategy, bit slip tolerance, fly wheeling, etc. In addition, cumulative quality data generation, on-board self diagnostics, and status/control processing are all integrated in this single card design. This level of functionality and very high data rate is made possible by the design of NASA application specific Gallium Arsenide (GaAs) Very Large Scale Integrated (VLSI) circuits to support space telemetry data system standards specified by the Consultative Committee for Space Data Systems. This paper will describe functions performed by this card and its supporting VLSI components.
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Gomes, Fany Catherine Dias. "Retaining MBAs, from employees' point of view." Master's thesis, NSBE - UNL, 2009. http://hdl.handle.net/10362/9502.
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A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and EconomicsThe purpose of this study is to discuss retention strategies used by Human Resource Management to retain knowledge workers, particularly MBAs. This Work Project is a qualitative analysis taking into consideration MBAs point of view through semi-structured interviews. This document takes their opinions in order to discuss the possible gaps between the current HRM strategies used and the ones considered as effective by MBAs. The interviews were conducted with a sample of 24 participants all of them with a MBA Degree which gave to the analysis heterogeneity because of their different backgrounds. The interviews were recorded and then transcribed. A master table with the results was then elaborated. Concerning the findings, some of them confirmed the literature review. But new results arose from the interviews, which may be interesting for future research.
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Berry, N. D. "Process modelling of the MBBR AS hybrid process." Thesis, Cranfield University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.273470.
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Kibalo, Tom, and Ben Miles. "A 400 Mbps High Density Digital Recording System." International Foundation for Telemetering, 1995. http://hdl.handle.net/10150/608542.
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International Telemetering Conference Proceedings / October 30-November 02, 1995 / Riviera Hotel, Las Vegas, NevadaA highly versatile 400 Mbps High Density Digital Recording System for telemetry and GPS downlink acquisition at Vandenberg AFB, California is discussed. The system supports 24 channels of data acquisition, is realized using entirely COTS components, and achieves full IRIG compatibility without any compromise in the desired system performance and operation.
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Davis, Don, Toby Bennett, and Jonathan Harris. "A VERY LOW COST 150 MBPS DESKTOP CCSDS GATEWAY." International Foundation for Telemetering, 1995. http://hdl.handle.net/10150/608413.
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International Telemetering Conference Proceedings / October 30-November 02, 1995 / Riviera Hotel, Las Vegas, NevadaThe wide use of standard packet telemetry protocols based on the Consultative Committee for Space Data Systems (CCSDS) recommendations in future space science missions has created a large demand for low-cost ground CCSDS processing systems. Some of the National Aeronautics and Space Administration (NASA) missions using CCSDS telemetry include Small Explorer, Earth Observing System (EOS), Space Station, and Advanced Composite Explorer. For each mission, ground telemetry systems are typically used in a variety of applications including spacecraft development facilities, mission control centers, science data processing sites, tracking stations, launch support equipment, and compatibility test systems. The future deployment of EOS spacecraft allowing direct broadcast of data to science users will further increase demand for such systems. For the last ten years, the Data Systems Technology Division (DSTD) at NASA Goddard Space Flight Center (GSFC) has been applying state-of-the-art commercial Very Large Scale Integration (VLSI) Application Specific Integrated Circuit (ASIC) technology to further reduce the cost of ground telemetry data systems. As a continuation of this effort, a new desktop CCSDS processing system is being prototyped that offers up to 150 Mbps performance at a replication cost of less than $20K. This system acts as a gateway that captures and processes CCSDS telemetry streams and delivers them to users over standard commercial network interfaces. This paper describes the development of this prototype system based on the Peripheral Component Interconnect (PCI) bus and 0.6 micron complementary metal oxide semiconductor (CMOS) ASIC technology. The system performs frame synchronization, bit transition density decoding, cyclic redundancy code (CRC) error checking, Reed-Solomon decoding, virtual channel sorting/filtering, packet extraction, and quality annotation and accounting at data rates up to and beyond 150 Mbps.
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Enterkine, Robert. "A 4 Mbps Digitizer with 100 kHz Signal Bandwidth." International Foundation for Telemetering, 1987. http://hdl.handle.net/10150/615332.
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International Telemetering Conference Proceedings / October 26-29, 1987 / Town and Country Hotel, San Diego, CaliforniaThis paper presents a non-standard digitization scheme which samples the data asymmetrically in order to maximize data bandwidth. Two frame sychronization words are utilized in a separated manner to permit their replacement with the average value of adjacent data words during the decommutation process.
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Pinho, Margarida Louro da Fonseca. "Aplicabilidade do reactor MBBR no tratamento de efluentes vínicos." Master's thesis, Universidade de Aveiro, 2007. http://hdl.handle.net/10773/539.
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Mestrado em Gestão Ambiental, Materiais e Valorização de ResíduosO presente trabalho pretendeu analisar a aplicabilidade do reactor do tipo Moving Bed Biofilm Reactor (MBBR) no tratamento de efluentes vínicos. A natureza dos efluentes provenientes das adegas depende da região e do tipo de vinho processado e, para além disso, a sua quantidade e a qualidade variam significativamente ao longo do ano. Os principais objectivos deste trabalho foram analisar a aplicabilidade do reactor MBBR no tratamento de efluentes vínicos a operar com um tempo de retenção hidráulico de 24 horas, comparar o desempenho de reactores quando são utilizados meios de enchimento com características diferentes, comparar o desempenho de reactores com e sem recirculação de lamas e analisar o comportamento hidráulico deste tipo de reactores com e sem a presença de biomassa. Foram realizados ensaios em cinco reactores à escala laboratorial, em que quatro deles tinham enchimento, dos quais dois operaram com recirculação de lamas e os outros dois sem recirculação. O quinto reactor simulou um reactor de lamas activadas convencional com recirculação de lamas. Utilizaram-se dois tipos de enchimento, o Bioflow 9 e o Bioflow 40. Os modelos de escoamento hidráulico dos diferentes reactores foram determinados recorrendo a ensaios de tracer com e sem a presença de biomassa. Os ensaios efectuados demonstraram que os reactores que possuem enchimento têm comportamentos hidráulicos idênticos, sendo ambos caracterizados por modelos de mistura perfeita com zonas mortas e a percentagem de zonas mortas diminui nos ensaios realizados com biomassa (35-36% de zonas mortas para 10-12% de zonas mortas), concluindo-se que o grau de mistura melhora com a existência de biomassa. O reactor de lamas activadas foi caracterizado, em ambos os ensaios, pelo modelo de mistura perfeita com zonas mortas e curto-circuito, havendo uma ligeira alteração dos parâmetros quando o reactor opera com biomassa (28% de zonas mortas, 9% de curto-circuito para 26% de zonas mortas e 10% de curto-circuito). No presente estudo verificou-se que as condições limite de operação dos reactores foram alcançadas para um TRH de 24 h, 50% da altura do reactor com enchimento Bioflow 9 e o CQOalimentação = 8000 mg.L-1 (8,0. kgCQO.m-3.d- 1). Nestas condições o efluente tratado apresentou um CQOsolúvel = 1500 mg.L-1 correspondente a uma percentagem de remoção de CQO de 81%. Verificou-se também que para todos os reactores e em todas as condições operatórias testadas até à carga orgânica 6,5 kgCQO.m-3.d-1, a percentagem de remoção de CQO foi superior a 90%. Os resultados mais elevados registaram-se na carga 6,0 kgCQO.m-3.d-1, com valores próximos de 98%. Os valores de CQOsolúvel do efluente tratado nos diferentes reactores não ultrapassaram os 150 mg.L-1 até à carga 6,0 kgCQO.m-3.d-1, verificando-se um aumento significativo em cargas superiores. Concluiu-se que a recirculação de biomassa suspensa não exerce efeitos positivos na eficiência dos reactores, no entanto durante o período de arranque diminui significativamente o tempo de estabilização dos mesmos. ABSTRACT: The present study intended to evaluate the applicability of a MBBR reactor for the treatment of winery wastewaters. The wastewater originated in wine cellars strongly depends on the region and the type of wine processed and also its quantity and quality changes substantially during the year. The aims of this experimental study were to analyse the applicability of a MBBR reactor for the winery wastewater treatment operating with a hydraulic retention time of 24 hours, to compare the performance of reactors when different packing bed materials were used, to compare the performance of reactors with and without sludge recycling, and finally to examine the hydraulic behaviour of each reactor with and without biomass. Experiments were conducted with five lab-scale reactors where four had packing material, two operating with sludge recycling, two without it and a fifth reactor simulated a conventional activated sludge system. Two types of carrier elements were used, the Bioflow 9 and the Bioflow 40. The hydraulic flow models for the five reactors were determined recoursing to experimental studies with tracer elements in the presence and in the absence of biomass. Tracer studies demonstrated that the reactors filled with carrier elements had identical flow models and behaved as complete mixing reactors with dead spaces. The fraction of dead spaces decreases in experiments with biomass (35-36% of dead spaces to 10-12% of dead spaces), concluding that the degree of mixture improves in the presence of biomass. The activated sludge flow model was characterized, in both cases, as complete mixing reactor with dead spaces and short-circuiting with a slightly difference on the parameters in the presence of biomass (28% of dead spaces, 9% of short-circuiting to 26% of dead spaces and 10% of short-circuiting). In the present study it was verified that the limit operation conditions of the reactors were reached for a HRT of 24 h, 50% of the reactor volume packed with Bioflow 9 and a CODfeed= 8000 mg.L-1 (8,0 kgCOD.m-3.d-1). At this operational conditions the treated wastewater had a CODsoluble = 1500 mg.L-1 corresponding to a COD removal rate of 81%. It was also verified that for all the reactors and in all the operation conditions up to the organic load applied of 6,5 kgCOD.m-3.d-1, the COD removal rate was higher than 90%. The highest results were obtained at an organic load of 6,0 kgCOD.m-3.d-1 with values near 98%. The COD soluble values of the treated winery wastewater in the different reactors didn’t exceed 150 mg.L-1 up to an organic load of 6,0 kgCOD.m-3.d-1, and for higher loads a significant increase was verified. The sludge recycling doesn’t affect in a positive way the efficiency of the reactors, although during the start-up phase the reduction of the stabilization time was significant.
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Lanko, Iryna. "Anaerobic acidification of cheese-whey in the MBBR reactor." Master's thesis, Universidade de Aveiro, 2011. http://hdl.handle.net/10773/7456.
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Mestrado em Estudos AmbientaisIn this study cheese-whey conversion into VFAs as a source for biopolymers production was investigated. Cheese-whey was chosen due to its high organic content being a by-product from the cheese production factory, as a part of valorisation methodology for industrial waste streams. Cheese-whey acidification process was used as an alternative to the waste treatment technologies. To study the acidification of cheese-whey, a set of experiments was carried out to produce short-chain volatile fatty acids (VFAs), in order to find out its ratio to the total chemical oxygen demand (tCOD) of feed present in the reactor. The proportional amounts of Acetic, Propionic and i-Butyric acids towards the rest of the VFAs were also important in order to evaluate the MBBR efficiency for different operational parameters such as hydraulic retention time (HRT), alkalinity and organic load rate applied (OLR). To fulfil these goals the mass balances of the system were performed. The maximum production rates of Acetic, Propionic and i-Butyric acids associated with simultaneous changes in OLR and alkalinity at a constant HRT of 12 h, were investigated (70% and 65% of total VFAs produced – at Phases 0 and 4, respectively). The degree of acidification of cheese-whey to the short-chain VFAs was about 33% and 27% of the influent COD concentration, at Phases 0 and 4, respectively. The optimum operational conditions under study where the maximum production rates of Acetic, Propionic and i-Butyric acids occurred were at an alkalinity of 3.6 gCaCO3/L and an OLR = 35 gCOD/L*d (Phase 4). At this optimum conditions for acids production, the average rate of COD removal was equal to 20% and the rate of methane production was equal to zero.
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Reznák, Pavel. "Hypoteční zástavní listy (MBS) v USA." Master's thesis, Vysoká škola ekonomická v Praze, 2011. http://www.nusl.cz/ntk/nusl-81640.
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Má diplomová práce se zabývá Mortgage Backed Securities, což jsou cenné papíry kryté hypotékami. V první části práce jsou MBS zobrazeny jako část skupiny strukturovaných aktiv. Je zde provedeno jejich srovnání s ostatními sekuritizačními instrumenty z hlediska struktury a vlastností a také je znázorněno jaká část jim připadá na sekuritizačním trhu. V další části je věnován důraz na podkladová aktiva MBS, tedy hypotéky. Důkladně je rozebrán americký hypoteční trh, druhy a objem poskytnutých půjček a jejich specifika. Jsou popsány polovládní agentury specifické pro americký trh, které napomáhají rozvoji hypotečního trhu. Hlavní část práce je věnována popisu tvorby Mortgage Backed Security, značná část se zabývá jednotlivými druhy a charakteristikami MBS. Je zde popsáno, jaký druh je vhodný pro určité typy investorů. Důraz je kladen na riziko předčasného splacení, tedy riziko spojené pouze s hypotéčními produkty. Závěrečná kapitola se věnuje jednotlivým typům MBS ze statistického hlediska. Je znázorněn jejich celkový objem na dvou hlavních trzích, v USA a Evropě, dále jsou popsány počty emisí jednotlivých druhů a další zajímavé statistické údaje spojené s MBS trhy.
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Svensson, Niklas. "Fatigue Analysis with Loads from MBS." Thesis, KTH, Maskinkonstruktion (Inst.), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-168720.
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Detta examensarbete har utförts i samarbete med Scania CV AB, en lastbils- och busstillverkare. Scania tror att en stor del i att behålla en ledande position är att erbjuda sina kunder pålitlighet, bland annat i form av livslängd. På grund av detta så är utbyggnad av kompetens och kunskap kring utmattningsanalys alltid aktuellt. Simuleringsdriven produktutveckling har dessutom ökat intresset för simuleringar tidigare i produktutvecklingen. Detta skapar nya utmaningar då det kräver att utmattningsanalyser utförs innan en fysisk prototyp finns. Då laster krävs för utmattningsanalyser är en tänkbar lösning att skapa lastfall med multibody simulations (MBS) med virtuella prototypfordon körandes en virtuell provbana.Huvudsyftet med detta arbete är att undersöka potentialen för att utföra analyser med laster från MBS. Fyra olika analysmetoder, som används inom Scania, har utförts med laster från MBS istället för från provbana. En utvärdering av metodernas robusthet och deras resultat jämfört med resultat från testrigg var tänkt att ge en indikation för vilken virtuell metod som har störst potential. Ett rammonterat inverterfäste som gått sönder i testrigg analyserades under arbetet. En modell av komponenten genererades i Abaqus och importerades i Adams för MBS. Laster som uppmättes i Adams användes för att utföra de olika utmattningsanalyserna.Det visade sig att två metoder var mer lovande än övriga: Dynamisk simulering med PSD och Superposition av modala spänningar. Men, utmattningsuppskattningarna från de genererade lasterna överensstämde inte med utfallet från det fysiska testet. I testrigg gick komponenten sönder medan analyserna indikerade att den inte skulle komma nära utmattningsbrott. Genom att jämföra lastsignalerna från testrigg och MBS uppdagades det att signalerna avvek kraftigt från varandra. Analys med testriggsignal indikerade att komponenten skulle gå sönder, vilket den också gjorde. Användande av lastsignalen från provbanan ledde däremot till ungefär samma skada som analyserna med MBS gav.Dessa resultat indikerar att det finns potential för utmattningsanalyser med virtuellt anhållna laster. Vidare undersökningar med ytterligare komponenter behöver dock genomföras innan definitiva slutsatser kan dras. Att utröna anledningen till att provet i testrigg varit tuffare än verkligheten är också av intresse.Scania is a truck and bus developer. They believe that reliability, which is strongly associated with life length, has been critical in achieving a leading position and is key to retaining it. Therefore, there is a continuous drive to increase their capability to simulate life length, specifically fatigue. Additionally, the recent popularity of simulation driven product development has created an additional interest in performing simulations earlier in the product development process. This creates a challenge since it requires fatigue analyses to be performed before prototype vehicles are available. Since loads are required for fatigue analyses, one solution is to perform a multibody simulation (MBS) of a virtual prototype vehicle on a virtual test track and derive load cases.This thesis investigated the possibility of using loads derived from MBS simulations to perform fatigue analyses. Four different simulation methods which are currently used by Scania were evaluated with MBS loads instead of physically measured loads. By comparing the methods’ results to those of physical tests, the virtual methods with the greatest potential were identified. A chassis mounted inverter bracket was analyzed in this work. The component was modeled in Abaqus, a model which then was merged into a complete bus model in Adams. Next, this model was run as an MBS over the virtual test track and load data was extracted. The component was then analyzed with different fatigue analysis methods, with the data from the MBS used as input. The fatigue results were then compared with the results of a physical shake rig test of the same component.Two methods were found to be most promising: Dynamic simulation with PSD and Superposition of modal stresses. Interestingly, the fatigue estimation for these methods substantially differed from the outcome of the physical test. The component failed in the physical test but according to the simulation it should have survived. Upon further investigation, it was found that the component was subjected to higher loads in the shake rig than on the shake track. A fatigue simulation using the signal from the shake rig agreed with the outcome of the physical test, namely failure. Analysis using the figures from the test track gave values similar to the results for analyses with MBS loads.These results suggest that this type of virtual analysis has potential. But before more definite conclusions can be drawn further investigations with more than one component need to be performed. Another path of investigation is to look at why the shake rig test is more severe than the virtual shake track.
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Pangallo, Kristin C. "Halogenated 1'-methyl-1,2'-bipyrroles (MBPs) in the Norwestern Atlantic." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/55159.
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Thesis (Ph. D.)--Joint Program in Oceanography/Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences; and the Woods Hole Oceanographic Institution), 2009.Cataloged from PDF version of thesis.
Includes bibliographical references.
Halogenated 1'-methyl-1,2'-bipyrroles (MBPs) are a distinctive class of marine organic compounds. They are naturally produced, they have a unique carbon structure, they are highly halogenated, and they bioaccumulate in upper trophic levels. MBPs share many characteristics with persistent organic pollutants (POPs), and may prove to be useful natural analogues for these anthropogenic compounds. Further, their unique structure suggests that their biosynthetic organism(s) may have new genes to add to current knowledge of biosynthetic chemistry. The objectives of this dissertation were to further clarify the environmental distribution of MBPs, to examine whether MBPs biomagnify, and to investigate possible origins of these compounds through their stable nitrogen isotopic signatures. Results from these investigations have shown that over 40 highly brominated MBP congeners are present in marine mammals, fish, and squid from the Northwestern Atlantic Ocean. The most abundant MBPs do appear to biomagnify through the food web to reach the concentrations observed in marine mammals. This additional evidence affords greater confidence in the use of MBPs as natural analogues for POPs. However, differences in the environmental chemistry of MBPs and anthropogenic compounds are also evident, and may be due to these compounds' different origins, or to the capacity of degradative enzymes to act upon them.
(cont.) Finally, compound-specific nitrogen isotope analyses on MBPs isolated from dolphin blubber show that these compounds are dramatically enriched in 15N relative to other biosynthetic organic compounds. This enrichment is likely a signal imparted during biosynthesis, and may assist in elucidating the organism(s) and mechanism(s) responsible for the biosynthesis of MBPs.
by Kristin C. Pangallo.
Ph.D.
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Easter, Anna. "Preliminary testing of the modes of being present scale (MBPS) /." free to MU campus, to others for purchase, 1999. http://wwwlib.umi.com/cr/mo/fullcit?p9946253.
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Easter, Anna L. "Preliminary testing of the modes of being present scale (MBPS)." free to MU campus, to others for purchase, 1999. http://wwwlib.umi.com/cr/mo/fullcit?p9946253.
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Hosseini, Hooshyar Sima. "Feasibiity analysis of MBMS deployment with the introduction of LTE." Thesis, KTH, Kommunikationsnät, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-134712.
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Multimedia Broadcast Multicast service (MBMS) proposed by 3GPP for efficient use of network resources in broadcast and multicast services, provides the operator a delivery mechanism to simultaneously send to multiple recipients at high speed. Although MBMS was introduced in 3GPP Release 6 at the time of 3G networks, the MBMS feature did not find much attention from the 3G network operators. This thesis studies the technical and market feasibility for a successful MBMS deployment today at the time of commercial LTE deployment. UE and RAN advancements that make MBMS technologically feasible are studied together with the market feasibility factors such as user demand on media streaming and the impending data explosion. The thesis concludes that today at the time of LTE, it is more feasible from both technology and market perspectives to deploy MBMS in comparison to the time of 3G. As a future work, the thesis provides some suggestions that the operators should take care of before deploying MBMS.
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Yang, Liunan. "Heterogeneous MBS forwarder modeling and co-simulation." Thesis, KTH, Maskinkonstruktion (Inst.), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-176264.
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The forwarder acts as an important role in mechanized Cut-to-Length timber harvesting system. But the majority of forwarder products on the market are not suspended or simply suspended by bogies which limit the riding quality of forwarder and result in soil damage due to large tireground interaction force. The Forestry Research Institute of Sweden is developing an active controlled pendulum arm suspension system actuated by hydraulic cylinders on the forwarder prototype named XT28. The aim of this active suspension system is to compensate the inherent shortcomings of the current suspension solutions. The thesis project focuses on implementing a heterogeneous simulation methodology which integrates the Multi-Body System model of XT28 built in MSC ADAMS/View with active suspension control model developed in MATLAB/Simulink. Thus, the co-simulation process is visualized in ADAMS/View. The results show that the active controlled pendulum arm suspension could improve the riding quality in a large extend and reduce the force between tire and ground at the same time. The cosimulation between ADAMS and Simulink is proved as a feasible and efficient approach to study the active control system for pendulum arm suspension on XT28 forwarder.Skotaren har tillsammans med skördaren en central roll i den fullt mekaniserade kortvirkesmetoden för skogsavverkning. Majoriteten av dagens skotare på marknaden har sex eller åtta hjul, som är monterade parvis på boggilådor. Det innebär att de saknar chassidämpning, vilket begränsar operatörens komfort och orsakar även stora markskador på mjuk mark. Skogforsk koordinerar realiseringen av en fullskaleprototyp, som går under arbetsnamnet XT28, med sex hjul monterade på varsin pendelarm. Pendelarmarna har varsin hydraulcylinder som möjliggör aktiv helmaskinsdämpning. Detta examensarbete är inriktat på att skapa, demonstrera och verifiera en heterogen simuleringsmetodik, som integrerar och möjliggör samsimulering av en dynamisk mekanikmodell utvecklad i MSC Adams/View med en reglermodell för aktiv styrning av pendelarmarna. Reglermodellen har utvecklats i MATLAB / Simulink. Simuleringsresultaten, som visualiseras i Adams-miljön, visar att den aktiva pendelarmregleringen skulle kunna förbättra åkkomforten signifikant, och också kraftigt markkontaktkrafterna. Det visas att samsimulering mellan ADAMS och Simulink är en effektiv metod för att verifiera prestandan hos aktiva reglersystem för pendelarmsfjädring på prototypskotaren XT28.
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Jonfelt, Clara. "An evaluation of an MBBR anammox model - sensitivity analysis and calibration." Thesis, Uppsala universitet, Avdelningen för beräkningsvetenskap, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-312511.
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This master thesis is about mathematical modelling of the anammox process with a moving bed biofilm reactor (MBBR) for a reject water application. Specifically, the aim of my research was to find out whether the model proposed by Erik Lindblom in (Lindblom et al. 2016) is a good model for this purpose and worth continuous research and optimization. The code for the model, implemented in Matlab/Simulink, was given; although not initially functioning in the given condition. Some modifications needed to be done to make it function properly. In order to confirm that the code was working and used in a correct way some results in (Lindblom et al. 2016) were reproduced. Before starting the evaluation of the model, some much-needed optimizations of the code were done, substantially reducing the run time. A sensitivity analysis was done, and the five most sensitive parameters were picked out to be used in the calibration. The calibration improved the total fit of the model to the available measurements, although one of the model outputs could not be calibrated satisfactorily. In short, I found that although there are still problems left to solve before the model can be stated to accurately model the anammox process with MBBR, it appears promising. Most importantly, more measurement data are needed in order to make a proper validation and to do a better calibration.CONAN
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Davies, Emma [Verfasser]. "Charakterisierung der Teilchenausbreitung in einem Molekularstrahl eines MBMS-Systems / Emma Davies." Bielefeld : Universitätsbibliothek Bielefeld, 2019. http://d-nb.info/1197798080/34.
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O’Connell, Richard. "200 MBPS TO 1 GBPS DATA ACQUISITION & CAPTURE USING RACEWAY." International Foundation for Telemetering, 1997. http://hdl.handle.net/10150/607569.
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International Telemetering Conference Proceedings / October 27-30, 1997 / Riviera Hotel and Convention Center, Las Vegas, NevadaFor many years VME has been the platform of choice for high-performance, real-time data acquisition systems. VME’s longevity has been made possible in part by timely enhancements which have expanded system bandwidth and allowed systems to support ever increasing throughput. One of the most recent ANSI-standard extensions of the VME specification defines RACEway, a system of dynamically switched, 160 Mbyte/second board-to-board interconnects. In typical systems RACEway increases the internal bandwidth of a VME system by an order of magnitude. Since this bandwidth is both scaleable and deterministic, it is particularly well suited to high-performance, real-time systems. The potential of RACEway for very high-performance (200 Mbps to 1 Gbps) real-time systems has been recognized by both the VME industry and a growing number of system integrators. This recognition has yielded many new RACEway-ready VME products from more than a dozen vendors. In fact many significant real-time data acquisition systems that consist entirely of commercial-off-the-shelf (COTS) RACEway products are being developed and fielded today. This paper provides an overview of RACEway technology, identifies the types of RACEway equipment currently available, discusses how RACEway can be applied in high-performance data acquisition systems, and briefly describes two systems that acquiring and capturing real-time data streams at rates from 200 Mbps to 1 Gbps using RACEway.
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Líčeník, Adam. "Výpočtové modelování dynamiky převodových ústrojí v prostředí MBS." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2021. http://www.nusl.cz/ntk/nusl-449784.
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This diploma thesis is focused on compiling a computational model of the transmission of a Zetor Forterra HSX tractor in the Multibody software MSC ADAMS environment. It analyses the issue of creating gears in terms of vibration and noise. The thesis describes the creation of computational model which is used for simulation of the load conditions during tractor operation. The methodology is applied to a single-stage gearbox in which is verified. Then it is used on a model of a real tractor gearbox. The response of the input load conditions is projected during the forces in the engagement of the gears which are transmitted to the bearings.
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Gabarrón, Fernández Sara. "Diagnosis, assessment and optimisation of the design and operation of municipal MBRs." Doctoral thesis, Universitat de Girona, 2014. http://hdl.handle.net/10803/145434.
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This thesis is based on diagnosing, assessing and optimising the design and operation of membrane bioreactors (MBR) used for treating municipal wastewater. Specifically, this thesis has been carried out within the framework of seven municipal MBR wastewater treatment plants (WWTP) located in Catalonia with the collaboration of the Catalan Water Agency. Firstly, the design and operational issues of MBRs have been diagnosed, together with determining the main operational problems related to this technology. Secondly, the optimisation strategies applied in each full-scale MBR and the resulting costs were assessed. Finally, two of the operational problems identified were exhaustively evaluated: The ragging phenomenon and the biological nitrogen removal and operational costs optimisations. The research carried out in this thesis has enabled the design and operation of the municipal MBRs to be assessed while, at the same time, presenting several optimisation strategies which will improve the operation and costs of this technologyAquesta tesi es centra en la diagnosi, avaluació i optimització del disseny i l’operació dels bioreactors de membranes (BRM) pel tractament d’aigües residuals. Concretament, l’estudi s’ha realitzat dins del marc de treball de set estacions depuradores d’aigües residuals (EDARs) municipals amb tecnologia BRM presents a Catalunya en col·laboració amb l’Agència Catalana de l’Aigua. Primerament s’ha dut a terme la diagnosi de l’estat del disseny i operació dels BRMs i s’han determinat les problemàtiques associades a aquesta tecnologia. Així mateix, s’han avaluat les estratègies d’optimització realitzades i els corresponents costos d’operació. A partir de la diagnosis realitzada, dos dels principals problemes operacionals observats s’han caracteritzat i optimitzat: El ragging i l’optimització de l’eliminació biològica de nitrogen i dels costos d’operació. La recerca presentada en aquesta tesi ha permès diagnosticar l’estat dels BRMs, alhora que ha mostrat possibles vies d’optimització que permetran millorar l’operació i els costos associats a aquesta tecnologia
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Soleimani, Karizmeh Mohsen. "Investigation of Biologically-produced Solids in Moving Bed Bioreactor (MBBR) Treatment Systems." Thèse, Université d'Ottawa / University of Ottawa, 2012. http://hdl.handle.net/10393/23494.
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Lower production rate of solids in attached growth moving bed bioreactor (MBBR) systems as compared to conventional activated sludge (AS) systems makes them an attractive choice for municipal wastewater treatment (Ødergaard et al. 1994). However, the production of biologically-produced solids in MBBR systems is currently not well defined and requires additional investigation.
Three identical MBBR reactors were operated under the same dissolved oxygen (DO) concentration, influent pH and volume of Anoxkalnes media in two different experimental phases. In the first phase, the hydraulic retention time (HRT) kept constant in three reactors and SALR increased and in the second phase, the SALR was the constant parameter while HRT increased. These two phases were implemented to investigate the effect of variations in HRT and SALR on biologically-produced solids in MBBR reactors. This study demonstrated that HRT and SALR play an important role in settling characteristics of the biologically-produced solids in MBBR systems.
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Boyle, Kellie. "Optimization of Moving Bed Biofilm Reactor (MBBR) Operation for Brewery Wastewater Treatment." Thesis, Université d'Ottawa / University of Ottawa, 2019. http://hdl.handle.net/10393/39147.
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The significant rise in the number of micro-breweries in North America has increased the need for efficient on-site industrial wastewater facilities. Brewery wastewater is considered to be a high strength food industry wastewater with high variability in terms of both organic and hydraulic loading. Small breweries require cost-effective, reliable, and simple to operate treatment technologies to properly manage their brewery wastewaters. Moving bed biofilm reactor (MBBR) technology has shown promise at the lab-scale and full-scale with respect to brewery effluent treatment. MBBR systems have the capability for short hydraulic retention times (HRT), high organic loading rates, as well as increased treatment capacity and stability due to biofilm retention, all within a compact reactor size when compared to other aerobic and attached growth treatment options.
Two MBBR systems utilizing two different carrier types (Kaldnes K5 and Kontakt), and a suspended growth (SG) control reactor, were used in this study to investigate the impacts of surface area loading rate (SALR) and HRT on attached growth (AG) and SG kinetics and carrier type for brewery wastewater at 2000 mg-sCOD/L. An increase in SALR from 10-55 g-sCOD/m2/d while at an HRT of 12 hr resulted in no significant impact in total volumetric removal rates between the MBBR systems and the SG control reactor; however, MLSS concentrations were lower for the MBBR systems at SALRs below 55 g-sCOD/m2/d, which indicated AG contribution. Over 92% soluble chemical oxygen demand (sCOD) removal was achieved at each SALR in each of the three reactors. These results indicated that the reactors were substrate limited and SG controlled. Due to the SG dependency, the difference between the two types of carriers was indeterminate. A decrease in HRT from 12-3 hr while maintaining an SALR of 40 g-sCOD/m2/d resulted in a shift from SG to AG dependency in the MBBR systems. The total volumetric removal rates for the MBBR systems were significantly higher at HRTs of 3 and 4 hr as compared to the SG control reactor. The AG volumetric removal rates from both MBBR systems were highest at an HRT of 3 and 4 hr. At an HRT of 12 hr all three reactors maintained over 92% sCOD removal; however, at an HRT of 4 hr the SG control reactor dropped to 88% and at 3 hr to 61%, whereas the MBBR systems maintained 95% removal at an HRT of 4 hr and only decreased to 73% at 3 hr. These results indicated that the MBBR systems were more effective at lower HRT than the SG control reactor, with no significant difference observed between the two carrier types tested.
Biofilm morphology and viability from each of the two carriers utilized in the study of moving bed biofilm reactor (MBBR) treatment of brewery wastewater were investigated using stereoscopy and confocal laser scanning microscopy (CLSM) in combination with live/dead cell staining. Both carriers demonstrated thicker and more viable biofilms at high SALR and denser and less viable biofilms at low SALR. At lower HRT, the carriers reacted differently resulting in thicker, but less dense biofilms on the Kontakt carriers and thinner, but more dense biofilms on the K5 carriers. However, no trend in cell viability was observed with change in HRT. Although the systems were suspended growth (SG) dominated, based on the MBBR kinetics and carrier biofilm morphology and cell viability, either carrier would be a viable choice for an MBBR treating brewery wastewater at HRTs between 4 to 12 hr and SALRs between 10-55 g-sCOD/m2/d.
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Arabgol, Raheleh. "MBBR Produced Solids: Particle Characteristics, Settling Behaviour and Investigation of Influencing Factors." Thesis, Université d'Ottawa / University of Ottawa, 2021. http://hdl.handle.net/10393/41919.
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The separation of solids from biological wastewater treatment is an important step in the treatment process, as it has a significant impact on effluent water quality. The moving bed biofilm reactor (MBBR) technology is a proven upgrade or replacement wastewater treatment system for carbon and nitrogen removal. However, a challenge of this technology is the characteristics of the effluent solids that results in their poor settlement; with settling being the common method of solids removal. The main objective of this research is to understand and expand the current knowledge on the settling characteristics of MBBR produced solids and the parameters that influence them. In particular, in this dissertation, the impacts are studied of carrier types, biofilm thickness restraint design of carriers, and varying carbonaceous loading rates on MBBR performance, biofilm morphology, biofilm thickness, biofilm mass, biofilm density, biofilm detachment rate, solids production, particle size distribution (PSD) and particle settling velocity distribution (PSVD).
With this aim, three MBBR reactors housing three different carrier types were operated with varying loading rates. In order to investigate the effect of carrier geometrical properties on the MBBR system, the conventional, cylindrically-shaped, flat AnoxK™ K5 carrier with protected voids was compared to two newly-designed, saddle-shaped Z-carriers with the fully exposed surface area. Moreover, the AnoxK™ Z-200 carrier was compared to the AnoxK™ Z-400 carrier to evaluate the biofilm thickness restraint design of these carriers, where the Z-200 carrier is designed for greater biofilm thickness-restraint. The Z-200 carrier is designed to limit the biofilm thickness to the level of 200 µm as opposed to 400 µm for the Z-400 carrier. Finally, to investigate the effects of varying carbonaceous loading rates on system removal performance, biofilm characteristics and solids characteristics, further analyses were performed at three different loading rates of 1.5 to 2.5 and 6.0 g-sBOD/m2·d in steady-state conditions. The PSD and the PSVD analyses were combined to relate these two properties. A settling velocity distribution analytical method, the ViCAs, was applied in combination with microscopy imaging and micro-flow imaging to investigate the relation of PSD and settling behaviour of MBBR produced particles.
The obtained results have indicated that the carrier type significantly impacted the MBBR performance, biofilm, and particle characteristics. As such, the K5 carrier MBBR system demonstrated a statistically significantly higher carbonaceous removal rate and efficiency (3.8 ± 0.3 g-sBOD/m2·d and 59.9 ± 3.0% sBOD removal), higher biofilm thickness (281.1 ± 8.7 μm), higher biofilm mass per carrier (43.9 ± 1.0 mg), lower biofilm density (65.0 ± 1.5 kg/m3), lower biofilm detachment rate (1.7 ± 0.7 g-TSS/ m2·d) and hence lower solids production (0.7 ± 0.3 g-TSS/d) compared to the two Z-carriers. The Z-carriers' different shape exposes the biofilm to additional shear stress, which could explain why the Z-carriers have thinner and denser biofilm, resulting in higher solids production and lower system performance in comparison with K5. Moreover, the carrier type was also observed to impact the particle characteristics significantly. PSD analysis demonstrated a higher percentage of small particles in the Z-carrier system effluent and hence a significantly lower solids settling efficiency. Therefore, the solids produced in the K5 reactor have shown enhanced settling behaviour, consisting of larger particles with faster settling velocities compared to Z-carriers.
This dissertation also investigated the effects of restraint biofilm thickness on MBBR performance by comparing the Z-200 biofilm thickness-restraint carrier to the Z-400 carrier. No significant difference was observed in removal efficiency, biofilm morphology, biofilm density, biofilm detachment rate, and solids production between the Z-200 to the Z-400 carriers. The PSD and the PSVD analyses did not illustrate any significant difference in the particles’ settling behaviour for these two biofilm thickness restraint carriers, indicating that the biofilm thickness-restraint carrier design was not a controlling factor in the settling potential of MBBR produced solids.
Finally, this research studied the effect of varying loading rates and demonstrated a positive, strong linear correlation between the measured sBOD loading rate and the removal rate, indicating first-order BOD removal kinetics. The biofilm thickness, biofilm density and biofilm mass decreased when the surface area loading rate (SALR) was increased from 2.5 to 6.0 g-sBOD/m2·d. The solids retention time (SRT) was also shown to decrease by increasing the SALR, where the lowest SRT (1.7 ± 0.1 days) was observed at the highest SALR, with the highest cell viability (81.8 ± 1.7%). Significantly higher biofilm detachment rate and yield were observed at SALR 2.5, with the thickest biofilm and a higher percentage of dead cells. Consequently, a higher fraction of larger and rapidly settling particles was observed at SALR of 2.5 g-sBOD/m2·d, which leads to a significantly better settling behaviour of the MBBR effluent solids.
This study expands the current knowledge of MBBR-produced particle characteristics and settling behaviour. A comprehensive understanding of the MBBR system performance and the potential influencing factors on the MBBR produced solids, particle characteristics, and their settleability will lead to optimized MBBR design for future pilot- and full-scale applications of the MBBR.
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Bill, Karen Alexandra. "Evaluation of Alternative Electron Donors for Denitifying Moving Bed Biofilm Reactors (MBBRs)." Thesis, Virginia Tech, 2009. http://hdl.handle.net/10919/32597.
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Moving bed biofilm reactors (MBBRs) have been used effectively to reach low nutrient levels in northern Europe for nearly 20 years at cold temperatures. A relatively new technology to the US, the MBBR has most typically been used in a post-denitrification configuration with methanol for additional nitrate removal. Methanol has clearly been the most commonly used external carbon source for post-denitrification processes due to low cost and effectiveness. However, with the requirement for more US wastewater treatment plants to reach effluent total nitrogen levels approaching 3 mg/L, alternative electron donors could promote more rapid MBBR startup/acclimation times and increased cold weather denitrification rates.
Bench-scale MBBRs evaluating four different electron donor sources, specifically methanol, ethanol, glycerol, and sulfide (added as Na2S), were operated continuously at 12 °C, and performance was monitored by weekly sampling and insitu batch substrate limiting profile testing. Ethanol and glycerol, though visually exhibited much higher biofilm carrier biomass content, performed better than methanol in terms of removal rate (0.9 and 1.0 versus 0.6 g N/m²/day.) Maximum denitrification rate measurements from profile testing suggested that ethanol and glycerol (2.2 and 1.9 g N/m²/day, respectively) exhibited rates that were four times that of methanol (0.49 g N/m²/day.) Sulfide also performed much better than any of the other three electron donors with maximum rates at 3.6 g N/m²/day and with yield (COD/NO₃-N) that was similar to or slightly less than that of methanol. Overall, the yield and carbon utilization rates were much lower than expected for all four electron donors and much lower than previously reported; indicating that there could be advantages for attached growth versus suspended growth processes in terms of carbon utilization rates. The batch limiting NO₃-N and COD profiles were also used to find effective Ks values. These kinetic parameters describe NO₃-N and COD limitations into the biofilm, which affect the overall denitrification rates. Compared to the other electron donors, the maximum rate for methanol was quite low, but the estimated Ks value was also low (0.4 mg/L N). This suggests high NO₃-N affinity and low mass transfer resistance. The other three electron donors estimated higher Ks values, indicating that these biofilms have high diffusion resistance.
Biofilm process modeling is more complex than for mechanistic suspended growth, since mass transfer affects substrate to and into the biofilm. Simulating the bench-scale MBBR performance using BioWin 3.0, verified that μmax and boundary layer thickness play key roles in determining rates of substrate utilization. Adjustments in these parameters made it possible to mimic the MBBRs, but it is difficult to determine whether the differences are due to the MBBR process or the model.Master of Science
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Bayley, Gwain. "PC-based bit error rate analyser for a 2 Mbps data link." Thesis, University of Cape Town, 1988. http://hdl.handle.net/11427/23153.
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Bergqvist, Liv. "Förbehandling av skogsindustriellt avloppsvatten i pilotskala : Fluidiserad biofilmsprocess, robust försteg till luftad damm." Thesis, Karlstads universitet, Institutionen för ingenjörs- och kemivetenskaper, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-43563.
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Skogsindustriellt avloppsvatten behöver genomgå flertalet reningsprocesser innan det kan återföras till recipient. Vid Stora Ensos bruk i Skoghall används en luftad damm med slamåterföring som biologisk rening. Extraktivämnen i avloppsvatten försvårar luftning i dammen och problem med reningen kan uppstå då kommande skärpta utsläppskrav ska efterföljas från och med 2018. För att möjliggöra en kommande produktionsökning samtidigt som skärpta utsläppskrav följs driver nu Stora Enso ett investeringsprojekt för att effektivisera avloppsvattenreningen. En utredning ska genomföras med syfte att redovisa om ett försteg till den luftade dammen i form av en MBBR (Moving Bed Biofilm Reactor) skulle kunna underlätta rening i den luftade dammen. Om så är fallet kan en ökad produktion vara möjlig utan att ändra på dagens luftade damm samtidigt som utsläppsvillkor uppfylls. Detta är en fortsatt utredning av Karin Arvsells arbete som undersökte MBBR och luftad damm i labbskala. Stora skillnader mellan dessa arbeten är att vatten direkt från produktionen kontinuerligt går till försteget och att temperaturen i reaktorn inte regleras utan beror av vilka vattenflöden som skickas till luftad damm. En pilotanläggning byggdes upp på Stora Enso Skoghalls bruk där en Cipax-tank användes som reaktor och en bottenluftare byggdes på plats av en membranslang från luftad damm. Ett delflöde av det totala avloppsflödet till luftad damm leddes till reaktorn. Slang för inflöde gick in i botten av tanken för att bidra till omblandningen, resterande omblandning stod luftarsystemet för. Tanken var fylld med 800 liter vatten som reagerade med mikroorganismer växande som en biofilm på bärare. Uppehållstiden varierades med hjälp av en manuell ventil. För att utreda hur robust försteget är i förhållande till produktionsvariationer har TOC- och kloratreduktion analyserats samtidigt som tester har genomförts på ytaktiva ämnen, närsalter, SÄ, temperatur, VFA, SVI, EDTA, HRT och syrehalt. Luftningsförsök för att utreda hur effektiviteten på syresättningen påverkas av ett försteg samt kartläggning av mikroorganismer genomfördes. Pilotförsöken delades upp i tre olika försöksperioder. Under de 19 första dagarna genomfördes testperiod 1 där vattnet luftades i reaktorn utan bärare. Försöksperiod 2 var 45 dagar lång där avloppsvattnet reagerade med mikroorganismer växande som en biofilm på bärare. Försöksperiod 3 som var 16 dagar lång inleddes med att reaktorn isolerades. Utformningen av försöksperiod 3 är ett resultat av provsvar från försöksperiod 2 där det framkom att temperaturen sjönk nämnvärt under de timmar vattnet befann sig i reaktorn. Testperiod 2 visade reduktion av samtliga parametrar med en medelreduktion av TOC på 40 % och 86 % reduktion av klorat. Vid ytspänningsanalys visades en högre ytspänning på utgående vatten vilket tyder på att ytaktiva ämnen brutits ner. Detta underlättar luftningen vilket sågs tydligare efter luftningsförsök på ingående och utgående vatten där hastigheten för syretransporten dubblerades. Både frisimmande organismer och protozoer i form av klockdjur och toffeldjur hittades i vattnet. I samband med uppstart av testperiod 3 var CTMP-produktion och blekeri stoppat vilket ledde till att kvarvarande avloppsflöde hade en ingående temperatur på 51°C. Den höga temperaturen och det förändrade innehållet i avloppet samtidigt som reaktorn isolerades bidrog till att mikroorganismerna slogs ut. Klorat reducerades med 93 % och TOC reducerades med 19 %. Reduktionsgrader av övriga parametrar var lägre än tidigare och vid luftningsförsök visades ingen förbättring av syretransporten. Reduktionsgrader har varierat från dag till dag men då rimliga orsaker är kända kan resultaten anses trovärdiga, vilket innebär att ett biologiskt försteg i form av en MBBR som hanterar inkommande avloppsvatten med dess varierande temperatur kan underlätta rening för luftad damm. Ytaktiva ämnen bryts ner under den korta reaktionstiden i försteget och syretransporten dubbleras. Vid produktionsstörningar kan termofila förhållanden råda istället för mesofila som är fallet vid normalproduktion. Detta kan slå ut mikroorganismerna vilket påverkar avloppsvattenreningen negativt. För att lösa problemet kan eventuellt varma flöden ledas direkt till luftad damm eller att genom kylning hålla ingående temperatur under 45°C.Paper mill wastewater passes through several different purification steps before being reintroduced to the recipient. Stora Enso paper mill in Skoghall uses an aerated lagoon with sludge recirculation as biological treatment. Extractives in wastewater aggravates the aeration in the pond and problems with the purification can occur when stricter emission requirements needs to be followed from 2018. Stora Enso is now running an investment project to improve the efficiency of the wastewater treatment to enable future production growth while stricter emission standards are followed. A pre-treatment step before the aerated lagoon designed as a MBBR (Moving Bed Biofilm Reactor) will be analyzed to present whether it can ease the wastewater treatment in the aerated lagoon or not. If so, production growth could be possible without change the present aerated lagoon while emissions conditions are met. This is a further investigation from Karin Arvsells work that studied a MBBR and aerated lagoon in lab scale. Large differences between these studies are that the wastewater goes to the pre-treatment continuously and the temperature is not regulated. A pilot plant was built at Stora Enso Skoghall mill where a Cipax-tank was used as a reactor and an aerator was built with membrane from the aerated lagoon. A partial flow of the total wastewater flow to the aerated lagoon was passed to the reactor at the bottom of the tank. The incoming wastewater and the aerator mixed 800 liters of water with the microorganisms growing as a biofilm on the carriers. The hydraulic retention time was controlled with a manual valve. TOC- and chlorate reduction, extractives, nitrogen, phosphorus, suspended solids, temperature, VFA, SVI, EDTA, HRT and oxygen content are analyzed to find out how robust the pre-treatment is. Tests were made to analyze how effective the oxygen dissolves after a pre-treatment and to identify the microorganisms in the wastewater. The experiments were divided into three different periods. Under the first 19 days was trial 1 performed where the water reacted in the MBBR without carriers. Trial 2 was 45 days long and the wastewater was pre-treated with microorganisms growing on carriers. Trial 3 lasted for 16 days and then the wastewater was treated in an isolated tank with carriers. The design of trial 3 was a result of the test results from trial 2 where the temperature dropped significantly during the hours the wastewater was treated in the reactor. Trial 2 showed reduction of all parameters with an average reduction of 40 % of TOC and 86 % reduction of chlorate. Surface tension analysis demonstrated a higher surface tension after the pre-treatment step which indicates that extractives were decomposed. The higher surface tension will ease the aeration in the aerated lagoon which was shown in the aeration tests were the rate of oxygen transport was doubled. Both free-swimming organisms and protozoa were found in the water. At the start of trial 3 the production of CTMP and the bleaching process were stopped. As a result, the remaining wastewater had a temperature of 51°C. The high temperature and the changed content of the wastewater at the same time as the reactor was isolated resulted in an elimination of the microorganisms. Chlorate was reduced by 93 % and TOC by 19 %. The reductions of the other parameters were lower than before and the aeration trials showed no improvement in oxygen transport. The reduction varied from day to day but since reasonable causes are known, the results are considered reliable. This means that a biological pre-treatment step in form of a MBBR can ease the purification in the aerated lagoon. Extractives are decomposed during the short reaction time and the oxygen transport is duplicated. If the production is disrupted, thermophilic conditions may occur instead of mesophilic conditions which are the normal setting. This may eliminate the microorganisms which affect the wastewater treatment negatively. To solve the problem, the hot water could be led directly to the aerated lagoon or by cooling the water keep the incoming temperature under 45°C.
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Baus, Matthias. "Technologische Konzepte zur Herstellung von monolithischen bidirektionalen Schaltern (MBS) /." Aachen : Shaker, 2007. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=016472804&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.
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Hromádka, Adam. "Dynamika rotoru turbodmychadla s kluznými ložisky na bázi MBS." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2015. http://www.nusl.cz/ntk/nusl-231714.
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The first part of the thesis describes construction of turbochargers. The next chapter summarizes currently used methods to solve dynamics of vehicle turbocharger´s rotor. Build-up of the model of a rotor and substitution of a joint with a bearing is appended with advantages and disadvantages. Practical part of the thesis focusses at analyse of a specific rotor of turbocharger with use of MBS. Output of the analyse are rotor´s vibrations. Last chapter complains methods to improve the model.
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Fujii, Fábio Yugo. "Análise comparativa entre o processo de lodo ativado e o reator de biofilme de leite móvel na remoção de nitrogênio de esgoto sanitário." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/3/3147/tde-12122011-134438/.
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O processo de tratamento de esgoto por lodo ativado pode ser adaptado para o recebimento de maior carga orgânica ou para a remoção de nitrogênio por meio da introdução de suportes plásticos móveis, em um processo conhecido por IFAS Integrated Fixed-Film Activated Sludge. O objetivo do projeto é avaliar comparativamente os desempenhos dos sistemas de lodo ativado e IFAS na remoção de matéria orgânica e nitrogênio de esgoto doméstico, associados à variação da idade do lodo com referência na biomassa suspensa. O efeito da adição de suportes plásticos móveis em sistemas existentes de lodo ativado é avaliado como forma de subsidiar análises de viabilidade de emprego dessa solução para a ampliação e adaptação de estações de tratamento de esgotos domésticos. A pesquisa foi desenvolvida em escala piloto, mantendo dois sistemas em funcionamento em paralelo, um representando um sistema de lodo ativado com remoção de nitrogênio e outro idêntico, exceto para a introdução dos suportes plásticos móveis. Desta forma, foi possível atribuir a diferença nos resultados à presença de biomassa aderida. Foram utilizados elementos suporte com área superficial específica de 300 m²/m³ e fração de enchimento de 50%. Ambos os sistemas foram mantidos em operação estável e eficiente, considerando a remoção de matéria orgânica. No entanto, o sistema IFAS teve melhor desempenho na remoção de nitrogênio em todas as fases experimentais, confirmando as vantagens antecipadas. Os resultados foram verificados em termos de taxas de aplicação previstas para cada porção de biomassa, de acordo com as idades do lodo estudadas.The activated sludge wastewater treatment process can be retrofitted to either receive larger organic loads or for nitrogen removal by introducing plastic media carriers, in a process known as IFAS Integrated Fixed-Film Activated Sludge. The project aims to comparatively assess the performances of activated sludge and IFAS systems in removing organic matter and nitrogen from domestic sewage, associated to the variation of the sludge age with reference to the suspended biomass. The effect of adding plastic media carriers on existing activated sludge systems is evaluated as a subsidy for prefeasibility analysis of using this solution for the upgrading and retrofitting of municipal wastewater treatment plants. The study was developed on a pilot scale, operating two systems in parallel, representing an activated sludge system with nitrogen removal and another identical system except for the introduction of plastic media carriers. Thus, it was possible to assign the difference in results to the presence of attached biomass. Carriers were used with 300 m²/m³ specific surface area and 50% filling fraction. Both systems were kept under stable and efficient operation considering the removal of organic matter. However, the IFAS system had better performance at removing nitrogen in all experimental phases, confirming the anticipated advantages. The results were verified in terms of application rates expected for each portion of biomass in accordance with the sludge ages studied.
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Young, Bradley. "Nitrifying MBBR Performance Optimization in Temperate Climates Through Understanding Biofilm Morphology and Microbiome." Thesis, Université d'Ottawa / University of Ottawa, 2017. http://hdl.handle.net/10393/36001.
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Nitrification is currently the most common means of ammonia removal from wastewaters in temperate climates. In conventional suspended growth systems operating in northern climate regions, nitrification completely ceases at temperatures below 8°C. This is a considerable concern in passive treatment systems where wastewater temperatures can reach as low as 1°C for extended periods in the winter months. There is evidence biofilm technologies have the ability to nitrify at low temperatures, however, the literature is missing an understanding of low temperature nitrification and the subsequent impacts during seasonal changes. Additionally, there is an urgent need to gain a fundamental knowledge of the interplay between nitrifying performance optimization, biofilm morphology and the microbiome. This research aims to fill these needs using nitrifying moving bed biofilm reactors (MBBRs) at the lab and pilot scale.
This research concluded the most important factor determining MBBR carrier selection is a combination of surface area and pore space size. Although high surface area to volume carriers are attractive, the propensity to clog at high loading rates significantly decreases the removal rates. The viability of the biomass and ammonia oxidizing bacterial communities were not significantly changed, indicating the ammonia removal rates were reduced due to loss of surface area in the clogged carriers.
Operation at 1°C demonstrated significant rates of nitrification can be attained and stable for extended periods of operation. This study developed the first kinetic curve at 1°C with a maximum removal rate of 0.35 gN/m2·d. The performance of the post carbon removal nitrifying MBBR systems were shown to be enhanced at 1°C by an increase in the viable embedded biomass as well as thicker biofilm. This effectively increased the number of viable cells present during low temperature operation, which partially compensated for the significant decrease in rate of ammonia removal per nitrifying cell. At all studied loading rates at 1°C, the ammonia oxidizing bacteria were primarily in the family Nitrosomonadaceae (greater than 95 percent abundance of AOB population) and the nitrite oxidizing bacteria were primarily the genus Nitrospira (greater than 99 percent abundance of NOB population).
Operation at 20°C demonstrated high rates of removal in high loaded condition and robustness in extreme low loaded conditions. In both high loaded and extreme low loaded conditions the viability of the nitrifying biomass was sustained, with the family Nitrosomonadaceae as the primary ammonia oxidizing bacteria and the genus Nitrospira as the primary nitrite oxidizing bacteria. In extreme low loaded conditions and as well during start-up phases there are high prevalence of bacteria not directly related to the nitrification process. Their presence however indicates a dynamic process with changes in microbial composition within the biofilm matrix in response to varying conditions. Change in microbial composition likely helps stabilize and maintain the biofilm matrix enhancing process robustness in the temperate climates.
The new knowledge gained in this research optimizes the operation of nitrifying MBBR systems and elucidates the impacts of operational conditions on the biofilm and microbial community of nitrifying MBBR systems to further our understanding of nitrifying attached growth treatment technologies. The results of this study are anticipated to be used to design the first MBBR treatment system for year round ammonia removal in passive treatment systems located in northern climate regions.
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Forrest, Daina. "Tertiary Nitrifying Moving Bed-Biofilm Reactor: A Study of Carrier and Loading Effects on Nitrifying Kinetics, Biologically Produced Solids and Microbial Community." Thesis, Université d'Ottawa / University of Ottawa, 2014. http://hdl.handle.net/10393/31425.
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There is an increasing need for tertiary level wastewater treatment in Canada, driven in some cases by both provincial and federal regulation (Canada Gazette, 2012). Tertiary nitrification is the biologically mediated oxidation of nitrogen in the form of ammonia to nitrate following secondary treatment of carbonaceous material (Barnes & Bliss, 1983). The application of tertiary nitrification can prove challenging in the Canadian climate because of the temperature sensitive nature of nitrifiers (Hwang & Oleszkiewicz, 2007). Hence the greater than 1000 lagoon treatment plants currently in operation throughout country are susceptible to the full onslaught of weather effects and as such their nitrification processes become non-existent during the winter months (Delatolla et al., 2011,Hoang et al., 2014).
The moving bed biofilm reactor (MBBR) system has been studied and shows promise for continuous nitrification with prolonged exposure to cold temperatures (Hoang et al., 2014). They are marketed as cost effective and low operation intensive upgrade options for existing treatment plants as well as effective stand-alone systems and are currently in operation in many countries worldwide (WEF, 2011).
Despite the MBBRs initial development as a nitrification technology, recent research has been focused on COD removal systems. Studies showing that MBBR performance is directly related to surface area loading rates (SALRs) and not carrier type or shape have been performed exclusively on COD removal systems. The influence of MBBR carrier type on system solids production has also been solely studied for COD removal and the principles learnt have been transferred to tertiary nitrification systems without confirmation that they hold true. There is an absence of research on tertiary nitrifying kinetics; the effect of loading and carrier type, the nature of the solids produced and the carrier biofilm characteristics.
This study investigated three MBBR carrier types, the K3, M and P Anoxkaldnes carriers in an effort to quantify the effects of carrier type on nitrifying kinetics, biologically – produced solids and the bacterial community at normal and high loading conditions. Four tertiary nitrifying laboratory scale MBBRs were fed with synthetic wastewater and operated at a high loading condition (HLC) with a SALR of 1.89 ± 0.10 g-N/m2•d and a normal loading condition (NLC) with SALR of 0.91 ± 0.1 g-N/m2•d. At both HLC and NLC, results show no difference in the ammonia removal rates obtained by the different carrier types. It was however noticed that stressed operational conditions developed for the P and M carrier at the HLC due to the clogging of carrier pore spaces with biofilm and subsequent reductions in removal efficiency were observed. Despite the fact that larger surface area to volume carriers (such as the M and P) may lead to MBBR designs with smaller footprints and lower operational cost, the study revealed their greater propensity to become clogged under high loading conditions than the smaller surface area carriers (such as the K3 ). In addition the larger surface area carriers demonstrated longer transitional periods from high loading conditions to lower loading conditions.
A reduction in effluent total suspended solids (TSS) concentrations and improved solids settleability was observed with the shift from HLC to NLC. These results suggest the avoidance of high loading conditions in tertiary nitrifying MBBR operation. If low loading rates are not achievable then system design may have to consider the incorporation of coagulant use or an advanced solids separation technique to meet effluent solids regulation.
Variable pressure scanning electron microscope (VPSEM) images at HLC showed the presence of water mites on the K3 carrier and nematodes and ciliates on the M and P carriers. While NLC images do not show these organisms. VPSEM also measured thicker biofilms during the HLC than the NLC for all carriers. The results demonstrate a difference in the meso-environments and suggest a difference in the micro-environments of the biofilm attached to each carrier.
Microbial analysis showed no shifts in the dominant nitrifying species between the loading conditions, as well as no differences in the percent live /dead cell coverage. Nitrosomonas and Nitrospira were identified as the dominant AOB and NOB genera respectively at both the HLC and the NLC. Clear shifts in the microbial populations were observed for specific bacteria; with filamentous bacteria being observed at greater relative abundance at HLC than HLC. The increased relative abundance of filamentous organisms are also associated with the significantly poorer effluent settling characteristics observed at HLC.
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Kjellsdotter, Frida. "MBS-modelling of a heavy truck : Modelling and model validation." Thesis, KTH, Fordonsdynamik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-32076.
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As a result of the accelerating demands for faster development within the heavy vehicle industry, computer aided simulations have become a more important tool in the development process. Simulations can offer faster evaluation of loads acting on the vehicle and more cost effective fatigue life predictions than physical testing, since physical prototypes are not needed for load measurements or fatigue tests. However, accurate fatigue life predictions without physical verification are today a difficult task with many uncertainties, yet simulations are still an important part of modern product development.The objective of this work is to investigate the accuracy of a virtual model of a physical truck. The thesis focuses only on load simulation accuracy, leaving the material uncertainties aside. The vehicle model is built using Adams/Car with two different complexities of the frame model. A part of the work is to investigate how the frame model complexity affects the accuracy of the results.The virtual truck is simulated in a virtual test rig that excites the model with displacement on the wheel hubs to represent the forces induced when the truck is driven on the test track. The process to make a drive signal to the test rig is iterative. Simulations are also performed with the virtual model equipped with tires and driven on a virtual 3D road.Model performance is evaluated using TDDI (Time Domain Discrepancy Index) and pseudo-damage. TDDI evaluates the results in the time domain and the pseudo-damage considers the potential fatigue damage in the time series. A value of the TDDI below 0.3 and between 0.5 and 2 for the pseudo-damage is found good. The accuracy is approximately the same as can be repeated by different test engineers driving the same test schedule with the same vehicle.When iterating using the cab and the front and rear end of the frame as response feedback, the results for the model with the simple frame model show good values of TDDI and pseudo damage for the front end of the frame and the cab. Though the axles and the mid of the frame show poor results. The rear end of the frame does not reach the model performance targets, getting a too low value of the pseudo-damage while the TDDI value is good. The vehicle model with the complex frame shows similar results, when using the same response feedback, although the frame model is not optimized.The full vehicle model driving on 3d-road does not, at present, deliver accurate results. However, the relative damping for the beams, representing the leaf springs, has turned out to highly affect the results. The leaf spring model thus need to be optimized. The complex frame model is not showing results good enough to justify the extra modelling time. The accuracy of the full-vehicle model can be considerably improved by optimizing the model/-s of the wheel suspension and the complex frame model.
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Pykal, Vojtěch. "Výpočtové modelování dynamiky záběru čelního ozubeného soukolí v prostředí MBS." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2021. http://www.nusl.cz/ntk/nusl-445163.
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This master’s thesis is focused on the compilation of a computational modelling of gear mesh engagement dynamics of a spur gear by MBS approach. The user input is the specific geometry of gears, the operating speed, and the load torque. The output are the forces in the gear engagement and the reaction of the forces in the wheel bearings depending on the change in the stiffness of the gear due to the changing number of teeth in the engagement and the change in the axial distance. This model is characterized by a fast and relatively accurate calculation in the time domain. This means that it can react to changes in parameters during simulation such as axial distance, speed, and torque.
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Abtahi, Foroushani Seyed Mehran. "Towards tertiary micropollutants removal by bioaugmented moving bed biofilm reactors (MBBRs) and nanofiltration (NF)." Thesis, Toulouse 3, 2018. http://www.theses.fr/2018TOU30065.
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L'objectif de cette thèse est d'évaluer le concept d'un dispositif intégré comprenant un bioréacteur à biofilm fluidisé bio-augmenté, couplé à une membrane de nanofiltration de type polyelectrolyte multicouche, destiné à éliminer les micropolluants en traitement tertiaire des eaux usées domestiques, traitées conventionnellement. Les résultats montrent que, pour des micropolluants ciblés, chacun des procédés est efficace comme traitement tertiaire. Les mécanismes biologiques et de rétention membranaires sont explicités. Cependant des challenges restent à relever en particulier pour l'étape de bio augmentation (survie et implantation de la souche apportée) pour une exploitation de cette étape. D'autre part, des investigations plus poussées sont nécessaires à l'élaboration d'une membrane fiable et robuste. Un tel procédé couplé MBBR-NF pourra alors être entièrement justifié dans le contexte d'une élimination performante de micropolluants ciblés. Il aura toute sa place dans le panel des technologies vertes pour la préservation de l'environnementThis thesis aims at answering whether the concept of an integrated layout comprised of a coupled "bioaugmented moving bed biofilm reactors (bMBBRs) - polyelectrolyte multilayer (PEM)-based nanofiltration (NF) membrane" can be considered as a promising technology to eliminate target MPs from conventionally-treated municipal wastewater. Results presented herein indicate that each given component of the layout is efficient in the tertiary removal of MPs. Still, several challenges ahead of the process bioaugmentation (such as the survival and maintenance of inoculated strains) must be in-depth studied to find convenient operating solutions. On the other hand, further investigations are definitely needed to achieve a robust PEM-based membrane as a long-lasting technology. Even though a coupled bMBBR-NF system for enhanced MPs removal can be experimentally justified is, however, practically questionable. "The tale of bMBBR-NF" deserves much more scientific endeavors as plenty of environmental considerations are placed in, whereby achieving a future Green technology will not be far from our expectation
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Sevaille, Laurent. "Inhibition de métallo-B-lactamases (MBLs) pour lutter contre la résistance bactérienne aux antibiotiques." Thesis, Montpellier, 2018. http://www.theses.fr/2018MONTS136.
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La propagation de bactéries à Gram négatif multirésistantes aux antibiotiques représente un problème de santé publique majeur urgent à résoudre car le risque d’un retour à l’ère pré-antibiotique est réel. Parmi les modes de résistance existant, la production de métallo-B-lactamases (MBLs) responsables de l’inactivation des B-lactamines, la famille d’antibiotiques la plus utilisée, représente un challenge thérapeutique.Les travaux décrits dans ce manuscrit concernent la synthèse, la caractérisation et l’évaluation biologique de composés construits autour d’un cœur 2,4-dihydro-3H-1,2,4-triazole-3-thione substitués en deux positions. En se basant sur des études de criblage in silico et des études cristallographiques ayant permis d’identifier ce noyau comme un bon candidat dans le développement d’inhibiteurs de MBLs, la synthèse de différentes séries d’analogues a été entreprise afin d’identifier de nouveaux inhibiteurs pouvant potentiellement atteindre les tests cliniques.Dans un premier temps, une série de composés 4-amino-1,2,4-triazole-3-thione substitués en position 5 a été préparée en suivant des voies de synthèse classiques. Différentes séries ont ensuite été développées en introduisant une diversité structurale et fonctionnelle en position 4. Ces composés ont ensuite été testés sur des enzymes représentatives des 3 sous-classes de MBLs et les plus intéressants ont été évalués sur bactéries résistantes recombinantes.Afin de réaliser une évaluation rapide des produits synthétisés au sein du laboratoire, une méthode de criblage à moyen débit en plaque 96 puits sur cinq MBLs représentatives a été mise au point et validée grâce à l’appui de nos collaborateurs spécialistes des MBLsThe spread of multiresistant Gram negative bacteria is a growing threat to public health and the risk of return to the pre-antibiotic era is real. Among existing resistance modes, the production of metallo-B-lactamases (MBLs) responsible of the inactivation of B-lactams, the most used family of antibiotics, represents a therapeutical challenge.This manuscript describes the synthesis, characterization and biological evaluation of compounds built on a 2,4-dihydro-3H-1,2,4-triazole-3-thione scaffold substituted on two positions. Based on previous in silico screening and crystallographic studies, which identified this structure as a good candidate for MBLs inhibition, several series have been developed to found new inhibitors that could potentially be amenable to clinical development.First, 1,2,4-triazole-3-thione compounds substituted at position 5 have been prepared following classical pathways. Then, several series have been developed where the structural and functional diversity was introduced at position 4. Compounds have been tested on representative MBLs of the three sub-classes and the most interesting ones on recombinant resistant bacteria.To perform a rapid screening of compounds in the laboratory, a method of medium throughput screening inhibition tests on five MBLs performed in 96-wells plate has also been developed and validated during this study with the help of our collaborators specialists of MBLs
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Baus, Matthias [Verfasser]. "Technologische Konzepte zur Herstellung von Monolithischen Bidirektionalen Schaltern (MBS) / Matthias Baus." Aachen : Shaker, 2007. http://d-nb.info/1166512142/34.
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Sturrock, A. "The assessment of proton MBS as a biomarker for Huntington disease." Thesis, University College London (University of London), 2015. http://discovery.ucl.ac.uk/1460415/.
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The development of effective therapies for Huntington disease will require the identification of reproducible and objective markers of disease progression and abrogation. Magnetic Resonance Spectroscopy (MRS), a method of measuring brain metabolism within a specified region of interest, has shown potential as one such biomarker modality. Presented is work that demonstrates that putaminal MRS is an important biomarker modality, specifically in the context of clinical trials. At all time-points N-acetyl aspartate (NAA) and total NAA (tNAA), neuronal integrity markers, were lower in early manifest HD than control subjects. tNAA was consistently lower in pre-manifest HD than Controls. The gliosis marker, myo-inositol (mI), was robustly elevated in Early HD. Metabolites showed no longitudinal change for any group over 24 months. While motor assessments were better longitudinal measures of disease progresson, the robustness of tNAA permitted development of a model in which this metabolite is an outcome measure for future clinical trials. Thus, if one were to test a therapeutic with efficacy to partially normalise tNAA based on the difference between Control vs. Early HD, around 350 or 52 subjects (split between two treatment arms) would be required depending on whether 20% or 50% normalization of tNAA levels are expected. Brain metabolites most consistently correlated with disease burden but less so with motor phenotype. Direct and indirect evaluations of gliosis markers in biosamples were performed based on spectroscopic findings, and these suggested significant biomarker potential for the oxidation product lipid peroxidase (LPO). MRS demonstrates robust and consistent group metabolite differences in HD- affected individuals that correlate with disease burden. This modality has potential utility as an outcome measure for future therapeutic trials in HD, and furthermore may be useful in identifying novel biosample markers of disease.
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Baek, Jee hee. "Real estate securitization in Korea : application of PF ABS and MBS." Thesis, Massachusetts Institute of Technology, 2020. https://hdl.handle.net/1721.1/129106.
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Thesis: S.M. in Real Estate Development, Massachusetts Institute of Technology, Program in Real Estate Development in conjunction with the Center for Real Estate, September, 2020Cataloged from student-submitted PDF of thesis.
Includes bibliographical references (pages 54-55).
This thesis studies the application of securitization such as Project Finance Asset-Backed Securities (PF ABS) and Mortgage Backed Securities (MBS) as a method of real estate finance in Korea. Real estate in Korea has developed substantially with a remarkable economic growth in last 20 years. As real estate became one of the most popular investment methods, real estate finance also developed into a more diversified and complex structure. Real estate securitization provides an alternative to the traditional way of financing by liquidating the real estate related assets and makes access easier for all participants in the process. In Korea, real estate securitization was first adopted in 1999, with the initiation of the Asset Securitization Act. Though the concept of Asset-Backed Securities (ABS) started late compared to the global securitization industry, the Korean ABS market has grown so substantially that the total issuance amount reached $43 billion in 2019, having expanded by almost eight-fold from the beginning of the market in 1999. With a considerable progress in the market, some of securitization products have developed with distinctive features. Of many products, this thesis mainly studies two types of real estate securitization products, Project Finance Asset-backed Securities (PF ABS) and Mortgage-backed Securities (MBS). By going through the market trends and social context of both products, it will cover what can be suggested for further improvement of the real estate finance market in Korea
by Jee hee Baek.
S.M. in Real Estate Development
S.M.inRealEstateDevelopment Massachusetts Institute of Technology, Program in Real Estate Development in conjunction with the Center for Real Estate
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Frehse, Nico [Verfasser]. "Innen- und Außenhaftung der PartG mbB und ihrer Partner. / Nico Frehse." Berlin : Duncker & Humblot, 2018. http://d-nb.info/1238485391/34.
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Sultana, Razia. "Partial Nitration/anammox process in the moving bed biofilm reactor operated at low temperatures." Licentiate thesis, KTH, Mark- och vattenteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-145324.
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Mazurek, Agnieszka. "Nitrous oxide emissions from deammonification process under different operation conditions." Thesis, KTH, Mark- och vattenteknik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-180283.
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Wastewater treatment plays significant role in the environmental protection. The process has direct impact on quality of air and water. All treated sewage reaches fresh water reservoirs as well as gasses escaping from the process are emitted to the atmosphere. Main aim of the thesis is to determine N2O emissions from partial nitritation/Anammox (deammonification process) in one-stage system applied in MBBR technology. Whole project was operated successfully on two pilot-scale reactors parallel, fed by the same reject water. Both reactors were filled to capacity of 200 L each, where 40% of the working volume was fulfilled by Kaldnes carriers suspended in liquid by mechanical stirrer. First reactor (R1) presented strategy of intermittent aeration with ratio (R=1/3) and stable DO concentration at amount of 1.5 mg O2/L, whereas second one (R2) operated in constant aeration with variable values of dissolved oxygen which differ in range of 1.0-2.5 mg O2/L. Every week analyses of ammonium and nitrogen forms were carried out in influent and effluent by Hach-Lange cuvettes. Results of measurements showed high NH4+-N removal efficiency of approximately 95% for R1 reactor and 86% for R2. During the process, the continuous measurement of nitrous oxide in gaseous and liquid phase was performed by Teledyne data logger and Unisense microsensor. Measurements during 4 months resulted in assessment of nitrous oxide emission tendency dependent on aeration system. The result from reactor R1 showed that 1.0-2.4% of N-load was emitted as N2O to the atmosphere, and 0.05-0.28% was released as dissolved N2O in outgoing water. Regarding reactor R2 tendency of nitrous oxide production is similar. Estimated emission of N2O in gaseous phase in reactor R2 is 1.4-2.0% of nitrogen load and 0.02-0.39% in liquid phase. All gathered results are shown in the appendix of the paper.
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Abuzaid, Abdulmonem Ali. "Susceptibility and bactericidal activity of five biocides on Klebsiella pneumoniae and its association with efflux pump genes and antibiotic resistance." Thesis, University of Edinburgh, 2013. http://hdl.handle.net/1842/8822.
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Klebsiella pneumoniae is one of the top eight pathogens in hospitals, causing around 10% of hospital-acquired infections (nosocomial infections). It often produces extended-spectrum β-lactamase enzymes (ESBLs). This has led to numerous outbreaks, especially in intensive care, neonatal and surgical wards, associated with increases in morbidity and mortality. In order to reduce the number of infections caused by multi-resistant K. pneumoniae and improve standards of infection control within hospitals, there is extensive use of biocides as disinfectants and antiseptics. However this raises concerns that intensive exposure of hospital pathogens to biocides may result in the emergence of resistance not just to themselves but also to antibiotics. The reduced susceptibility to biocides and their relationship with resistance to antibiotics was assessed in this thesis. The susceptibility of 64 isolates of K. pneumoniae to five biocides preparations, Chlorhexidine (CHX), Benzalkonium chloride (BZK), Trigene, MediHex-4 (MH-4), Mediscrub (MS) and 17 antibiotics, were tested. The isolates of K. pneumoniae were collected from Royal Infirmary Hospital in Edinburgh (RIE) between 2006 and 2008 from different sites of infection. Antimicrobial susceptibility was tested by the agar double dilution method (DDM) and disc diffusion methods following the British Society for Antimicrobial Chemotherapy (BSAC) guidelines. A few isolates of K. pneumoniae showed insusceptibility to cephalosporins, colistin, rifampicin, trimethoprim and penicillin but not to carbapenems. Biocide susceptibility testing showed that 57, 55 and 61 strains had reduced susceptibility to Chlorhexidine, Trigene and Benzalkonium chloride, respectively, but not to MediHex-4 and Mediscrub. The effect of efflux pumps were determined by carbonyl cyanide m-chlorophenylhydrazone (CCCP) (10mg/L), which decreased the MICs of Chlorhexidine and Medihex-4 by 2 – 128 fold but had no impact on the MICs of Benzalkonium chloride, Trigene and Mediscrub. Six isolates of K. pneumoniae were chosen for their varying sensitivity to Chlorhexidine (CHX), and were tested for their minimum bactericidal concentration (MBC) to biocides. The high MBCs of Mediscrub and Trigene, over 500-fold greater than the minimum inhibitory concentration (MICs), indicates that these compounds are mainly bacteriostatic. Conversely, the MBCs of Chlorhexidine and MediHex-4, which contains chlorhexidine, were less than 10-times the MIC value indicating they are effective in killing the organism. However, this thesis showed how the killing capability of Chlorhexidine was hindered by the presence of organic matter, which compromised its effect. The relationship between reduced susceptibility to biocides and the carriage of antiseptic resistance genes, cepA, qacΔE1 and qacE was determined by polymerase chain reaction. The antiseptic resistance genes cepA, qacΔE1 and qacE were found in 56, 34 and 1 isolates respectively, and the levels of gene expression were detected by the reverse transcription polymerase chain reaction (RT-PCR). These results have shown that there was a close link between carriage of efflux pump genes, cepA, qacΔE1 and qacE genes and reduced susceptibility to biocides. Most strains showed decreased susceptibility to Chlorhexidine, Trigene and Benzalkonium chloride and this correlated with the carriage of the cepA, qacΔE1 and qacE genes encoding efflux. There was no correlation between the reduced susceptibility to biocides and antibiotic resistance in clinical isolates of K. pneumoniae.
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Undin, Klara. "Vattenrening i textilåtervinningsindustri : Reducering av nonylfenol, bromerade flamskyddsmedel och sulfat i re:newcells processvatten." Thesis, Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-78765.
Full textAbstract:
Kläder och textilier produceras och konsumeras i allt högre grad med stor påverkan på miljö, klimat och jordens resurser som följd. En attraktiv lösning på det är återvinning av kläder, vilket företaget re:newcell gör. Detta är en förstudie med syfte att undersöka vilka reningsmetoder re:newcell skulle kunna implementera för att förbättra sin vattenreningsprocess i framtiden. Tre ämnen vars halter i nuläget inte reduceras i reningen valdes ut till studien: nonylfenol, bromerade flamskyddsmedel och sulfat. En litteraturstudie kring dessa ämnen och möjliga reningsmetoder resulterade i att tre lämpliga reningsmetoder valdes ut till studien: ozonering, biologisk rening och jonbyte. En försöksplan utformades med målen att ta reda på (1) hur tidigare rapporterade ozondoser påverkade nonylfenolhalten i re:newcells vatten, (2) hur stor andel TOC (Total Organic Carbon) en MBBR (moving body bioreactor) kunde reducera och (3) ifall PBDE (bromerade flamskyddsmedel) och sulfat var möjliga att bryta ner med i en MBBR, (4) hur stort jonbytarfilter som skulle krävas i re:newcells process för att reducera sulfathalten samt (5) i vilken ordning reningsstegen bör implementeras i framtida reningsprocesser. Ozoneringsförsök utfördes på re:newcells laboratorium i Kristinehamn med totalt fem olika ozondoser. En biologisk MBBR utformades i laboratorium på Karlstad Universitet, där två olika uppehållstider testades för reducering av flamskyddsmedel, sulfat och TOC. Beräkningar på jonbytarfilter utfördes teoretiskt. En ozondos på 0,45 mgO3/mgCOD gav en reducering på ca 31 % och 0,75 mgO3/mgCOD gav 78 % reducering vid en nonylfenolhalt på 1100 mg/L. Resultaten från MBBR visar att bakterier trivs i re:newcells vatten och att de kunde reducera TOC med ca 50 %. Däremot kunde ingen reducering av sulfat uppmätas, vilket tyder på att ingen anaerob zon har uppstått. Halten av PBDE reducerades med ca 90 % med en uppehållstid på 45 h i MBBR, men om det beror på nedbrytning eller adsorption till slammet är inte fastställt. Resultaten från beräkningen på jonbytarfiltret visade att filtret behöver vara 5,7-15 m3 vid regenerering en gång per dygn i re:newcells nuvarande pilotskaliga process. Denna metod anses därmed inte vara en lämplig för sulfatreducering. Den framtida reningsprocessen föreslås starta med MBBR och efterföljande sedimentering, följt av kemfällning, sedimentering/flotation, sandfilter, ozonering och sist aktivkolfilter, men vidare studier rekommenderas rörande vilken ordning reningsstegen bör implementeras för optimal effekt. Vidare studier kring vilken ozondos som krävs och vilken uppehållstid som är optimal i MBBR föreslås också.Clothes and textiles are increasingly produced and consumed causing a major impact on the environment, the climate and the earth's resources. One solution to the problem is to recycle clothes that are no longer used, which is what the company re:newcell does. This is a feasibility study aimed at investigating what purification methods re:newcell could implement to improve their water purification process in the future. Three substances not currently purified sufficiently were selected for the study: nonylphenol, brominated flame retardants and sulfate. A literature review on these substances and possible purification methods for them resulted in that the following methods were selected for the study: ozonation, biological purification and ion exchange. An experimental plan was developed with the aim of finding out (1) how previously reported ozone doses affected the nonylphenol content in re:newcell's water, (2) how much TOC an MBBR (moving body bioreactor) could reduce, (3) and whether the levels of brominated flame retardants and sulphate were possible to reduce in it, (4) the required size of the ion exchange filter in re:newcells process to reduce sulfateand (5) the order in which the purification steps should be implemented in future purification processes. Ozonation experiments were carried out at re:newcell's laboratory in Kristinehamn with a total of five different ozone doses tested. A biological MBBR was designed in a laboratory at Karlstad University, where two different hydraulic retention times were tested for reducing flame retardants, sulfate and TOC. Calculations on ion exchange filters were performed theoretically. An ozone dose of 0.45 mgO3/mgCOD produced a reduction of about 31% and 0.75 mgO3/mgCOD produced a 78% reduction at a nonylphenol content of 1100 µg / L The results from MBBR showed that bacteria thrived in re:newcell´s water and that they can reduce TOC by about 50 %. However, reduction of sulfate could be measured, suggesting that no anaerobic zone has occured. The content of PBDE was reduced by about 90% with a hydraulic retention time of 45 hours in MBBR, but whether it is due to degradation or adsorbation to the sludge is not determined. The calculation regarding the ion exchange filter show that the filter needs to be 5,7-15 m3 when regenerated once a day in re:newcell's current pilot scale process this method is therefore not considered appropriate for sulfate reduction for re:newcell. The future purification process is proposed to start with MBBR and subsequent sedimentation, followed by chemical precipitation, sedimentation / flotation, sand filter, ozonation and last activated carbon filter, but further studies are recommended regarding which order the purification steps should be implemented for optimal effect. Further studies on which ozone dose is required and which residence time is optimal in MBBR are also suggested.
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Kokeš, Roman. "Multicastové směrování v UMTS sítích." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2008. http://www.nusl.cz/ntk/nusl-217544.
Full textAbstract:
This Master thesis is about multicast in mobile network 3rd generation UMTS(Universal Mobile Telecommunacitions System). UMTS network primary designs for data transfers and supports new services as real-time transfers of multimedia streams. This is reason why mobile network was equiped also with multicast service. When a lot of users want to receive same data (e.g. tv program) the network excessives load of transmission same data and the server have to keep connection to each user. Group 3GGP developed multicast service for UMTS, which name is MBMS (Multimedia Broadcast and Multicast Service). Thesis analyses function of this service in mobile network. First part describes basic principles of UMTS network and its structure. Next part focuses on change of main node (SGSN and GGSN) and of new node BM-SC(Broadcast-Multicast Service Center). This new node is main node for control of multicast transmission. BM-SC connects to server which provides multicast data for users and provisions individual phase of MBMS session. It was created new procedure which supports multicast session (e.g. Activate MBMS service). Next part focuses on GPRS Tunneling Protocol (GTP). This protocol is used for transfers control and user’s data in tunnels inside core network. This part describes structure of data and control messages. Last part analyzes multimedia transfers in UMTS with program Opnet Modeller.