Dissertations / Theses: 'SmpB'

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Holden, James Anthony, and jamesholden@netspace net au. "Vaccination Strategies for the Prevention of Swine Dysentery." RMIT University. Applied Sciences, 2006. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20070112.122102.

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The SmpA outer membrane lipoprotein of B. hyodysenteriae has several characteristics that indicate the potential to protect against swine dysentery (SD). It localises to the outer membrane and antibodies directed against SmpA can prevent the growth of B. hyodysenteriae in vitro. There is some variation observed in the distribution and expression of the SmpA lipoprotein, suggesting that vaccination with SmpA may not provide protection against challenge with a heterologous B. hyodysenteriae strain. This study has characterised the variation at the smpA locus, and in the process has identified a novel gene, smpB. There is very low similarity between smpB and smpA, with the exception of an identical lipoprotein signal sequence. This suggests that SmpB may be translocated to the outer membrane of B. hyodysenteriae in a similar fashion to SmpA. The results described in this thesis indicate that strains of B. hyodysenteriae harbour either smpA or smpB, but not both, explaining the earlier results of Turner et al. (1991). The presumed outer membrane location of SmpB lead to further investigations into its potential to protect mice from infection with B. hyodysenteriae. Swine Dysentery is a inflammatory disease of the swine colon. Therefore it is believed that a mucosal immune response may provide increased protection against challenge. In this study, vaccination of mice with recombinant SmpB elicited high levels of serum antibodies, induced the production of Interleukin-4 producing T lymphocytes and decreased the observed histological effects after challenge with virulent B. hyodysenteriae. In efforts to increase the protected conferred by vaccination with SmpB, recombinant Salmonella typhimurium STM-1 vaccines were created to express SmpB or deliver DNA vaccines encoding SmpB. Vaccination with these recombinant Salmonella vectors did not induce a measurable SmpB specific immune response. Macrophage survival and plasmid stability studies indicated that this was due to instability of the expression plasmids in STM-1. Although SmpB will only ever protect against strains of B. hyodysenteriae harbouring smpB, these results indicate that with further research, SmpB (and SmpA) may contribute to protection from SD. Toxin production is an important aspect of the pathogenesis of many pathogenic bacteria. Vaccination with attenuated toxins is commonly used to prevent disease. In this study, the B. hyodysenteriae â-haemolysin HlyA was used to vaccinate mice to determine the protection induced after challenge. Vaccination of mice with recombinant HlyA induced significant levels of serum antibodies and lowered the observed pathological effects after challenge of vaccinated mice with virulent B. hyodysenteriae. In an attempt to increase the mucosal immune response and therefore the protection afforded after vaccination with HlyA, recombinant S. typhimurium STM-1 strains were created to express HlyA or deliver DNA vaccines encoding HlyA. Similar to the recombinant STM-1 vaccines expressing SmpB, a HlyA specific immune response was not observed by ELISA or ELISPOT analysis. Plasmid stability trials revealed that the inability to induce a detectable HlyA specific immune response by recombinant STM-1 vaccination may be due to ins tability of the plasmids. Outer membrane proteins are often important components of vaccines against bacterial and viral pathogens. Considering the variation observed in the smpA locus in this study resulting in the identification of smpB, further investigation into the distribution and conservation of outer membrane encoding genes in B. hyodysenteriae strains was undertaken. In particular, the blpAEFG, vspABCD and vspEFGH clusters were analysed for their distribution. It was demonstrated that genes that are B. hyodysenteriae specific (vspABCD and vspEFGH) displayed higher levels of polymorphism than those that are distributed amongst non-pathogenic species, such as B. innocens (which contains blpAEFG). This suggests that the variation in the vspABCD and vspEFGH clusters amongst B. hyodysenteriae strains may be a result of the exposure to the host immune system. Further investigation was undertaken by PFGE analysis and 2D-gel electrophoresis, to analyse genomic and proteomic variation at a global level. Although strains of B. hyodyse nteriae produced several different electrophoretic types (ET) upon PFGE analysis, only limited correlation between the PFGE ET, the polymorphisms in vspABCD and vspEFGH and the presence of smpA/smpB were observed. 2D-gel electrophoresis analysis of outer membrane preparations of two B. hyodysenteriae strain revealed several distinct differences in the outer membrane between B. hyodysenteriae strains. The observed differences in the proteins contained in the outer membrane of B. hyodysenteriae is important for vaccine design, as the induction of cross protection between strains of B. hyodysenteriae is essential for a effective vaccine.

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Miller, Mickey R. "The Role of SmpB in Licensing tmRNA Entry into Stalled Ribosomes." BYU ScholarsArchive, 2013. https://scholarsarchive.byu.edu/etd/4162.

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Ribosomes translate the genetic information contained in mRNAs into protein by linking together amino acids with the help of aminoacyl-tRNAs. In bacteria, protein synthesis stalls when the ribosome reaches the 3'-end of truncated mRNA transcripts lacking a stop codon. Trans-translation is a conserved bacterial quality control process that rescues stalled ribosomes. Transfer-messenger RNA (tmRNA) and its protein partner SmpB mimic a tRNA by entering the A site of the ribosome and accepting the growing peptide chain. The ribosome releases the truncated mRNA and resumes translation on the tmRNA template. The open reading frame found on tmRNA encodes a peptide tag that marks the defective nascent peptide for proteolysis. A stop codon at the end of the open reading frame allows the ribosome to be recycled and engage in future rounds of translation.The entry of tmRNA into stalled ribosomes presents a challenge to our understanding of ribosome function because during the canonical decoding process, the ribosome specifically recognizes the codon-anticodon duplex formed between tRNA and mRNA in the A site. Recognition of proper base-pairing leads to conformational changes that accelerate GTP hydrolysis by EF-Tu and rapid accommodation of the tRNA into the ribosome for peptidyl transfer. The puzzle is that tmRNA enters stalled ribosomes and reacts with the nascent peptide in the absence of a codon-anticodon interaction. Instead, SmpB binding in the decoding center begins the rescue process, but it has been unclear how SmpB licenses tmRNA entry into stalled ribosomes. We analyzed a series of SmpB and ribosomal RNA mutants using pre-steady-state kinetic assays for EF-Tu activation and peptidyl transfer. Although the conserved 16S nucleotides A1492 and A1493 play an essential role in canonical decoding, they play little or no role in EF-Tu activation or peptidyl transfer to tmRNA. In contrast, a third nucleotide, G530, stacks with the side chain of SmpB residue His136, inducing conformational changes that lead to GTP hydrolysis by EF-Tu. A portion of the C-terminal tail forms a helix within the mRNA channel, monitoring the length of mRNA bound in the ribosome to avoid aborting productive protein synthesis. Helix formation in the mRNA channel is essential for accommodation and peptidyl transfer, but not for GTP hydrolysis. We show that conserved residues in the tail are essential for EF-Tu activation, accommodation, or translocation to the P site. Our findings lead to a clearer model of how the tmRNA-SmpB complex enters stalled ribosomes.

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Cazier, DeAnna June. "The Role of SmpB in the Early Stages of Trans-Translation." BYU ScholarsArchive, 2009. https://scholarsarchive.byu.edu/etd/2126.

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Ribosomes stall on defective messenger RNA transcripts in eubacteria. Without a mechanism to release stalled ribosomes, these cells would die. Transfer-messenger RNA (tmRNA) and small protein B (SmpB) reactivate stalled ribosomes in a process known as trans-translation. Together, tmRNA and SmpB mimic alanyl-tRNA, entering the A site of stalled ribosomes and accepting transfer of the stalled polypeptide. A portion of tmRNA is then positioned as a template for the ribosome to resume translating. The tmRNA open reading frame encodes a proteolysis tag to mark the aberrant polypeptide for degradation and a stop codon to release the ribosome. How are tmRNA and SmpB allowed into stalled ribosomes? In normal translation, decoding mechanisms carefully monitor the anticodon of tRNAs entering the A site and select only those that are complementary to the mRNA codon. How do tmRNA and SmpB get around the decoding machinery? It appears that interactions between the SmpB C-terminal tail and the decoding center are responsible. Using an in vivo tagging assay and an in vitro peptidyl-transfer assay, we monitored the effect of mutations in the SmpB tail on trans-translation. We found that mutations in SmpB that prevent helix formation are unable to support peptidyl transfer. We also found that while mutation of key nucleotides in the ribosomal decoding center severely inhibit peptidyl transfer to normal tRNAs, these mutations do not inhibit peptidyl transfer to tmRNA. We conclude that the SmpB tail stimulates peptidyl transfer by forming a helix that interacts with the ribosome to signal decoding in a novel manner. How is the tmRNA open reading frame positioned for the ribosome to resume translating? Mutation of the tmRNA nucleotide A86 alters reading frame selection. Using a genetic selection, we identified SmpB mutants that restore normal frame selection to A86C tmRNA without altering frame selection on wild-type tmRNA. Through rational mutation of the SmpB tail we identified an SmpB mutant that supports peptidyl transfer but prevents translation of the tmRNA open reading frame. We conclude that SmpB plays a functional role in selecting the tmRNA open reading frame.

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Watts, Talina Christensen. "Genetic analysis of the role of SmpB in determining frame on tmRNA /." Diss., CLICK HERE for online access, 2008. http://contentdm.lib.byu.edu/ETD/image/etd2501.pdf.

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Watts, Talina Christensen. "Genetic Analysis of the Role of SmpB in Establishing the Reading Frame on tmRNA." BYU ScholarsArchive, 2008. https://scholarsarchive.byu.edu/etd/1728.

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Ribosomes translate the genetic information encoded by mRNA into proteins. Defective mRNAs can cause stalling of translating ribosomes. The molecule tmRNA (transfer-messenger RNA) rescues stalled ribosomes in eubacteria. Together with its protein partner SmpB, tmRNA mimics a tRNA by entering the ribosomal A site and linking an alanine residue to the growing polypeptide chain. The ribosome then abandons the defective mRNA template and resumes translation on tmRNA, adding ten more amino acids to the nascent polypeptide. As a result of tmRNA action, stalled ribosomes are released and recycled, the defective mRNA is destroyed, and the aborted protein product is tagged for destruction by proteases. It is unknown how the ribosome correctly chooses the position on tmRNA to resume translation. Previous studies implicate the sequence UAGUC found immediately upstream of the first codon in the tmRNA open reading frame. These nucleotides are highly conserved in natural tmRNA sequences. Mutations in this area cause loss of tmRNA function and improper frame choice. Using a genetic selection that ties the life of E. coli cells to the function of tmRNA, we have identified several SmpB mutants that rescue an inactive tmRNA in which this upstream sequence was altered. This links SmpB to the function of these key tmRNA nucleotides. We show that our SmpB mutants affect frame choice using an in vivo assay for tagging in the various frames. We conclude that SmpB plays a role in setting the reading frame on tmRNA.

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Guyomar, Charlotte. "Études structurales de la trans-traduction, cible privilégiée pour le développement de nouveaux antibiotiques." Thesis, Rennes 1, 2018. http://www.theses.fr/2018REN1B039.

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Le travail retranscrit dans cette thèse porte sur un processus biologique impliqué dans le contrôle qualité de la synthèse protéique bactérienne : la trans-traduction. Ce processus permet de libérer les ribosomes bloqués sur des ARNm défectueux tout en détruisant les peptides et ARNm problématiques impliqués dans le blocage. Il nécessite deux acteurs principaux qui interagissent avec le ribosome: l’ARN transfert-messager (ARNtm) et la protéine SmpB. Dans un premier chapitre, une étude en cryo-microscopie électronique à transmission (cryo-MET) a permis d’obtenir deux structures à l’échelle atomique impliquant le ribosome et différents acteurs de la trans-traduction. La première structure met en évidence l’interaction entre la RNase R, enzyme responsable de la destruction des ARNm défectueux, et le ribosome bactérien. La deuxième structure a mené à la caractérisation des deux premiers états de la trans-traduction à une résolution quasi-atomique. De nouvelles interactions sont notamment observées entre la protéine SmpB et l’hélice H5 de l’ARNtm. Dans un second chapitre, la trans-traduction est exploitée comme cible pour le développement de nouveaux antibiotiques. En effet, cette voie de sauvetage est souvent vitale ou alors indispensable à la virulence bactérienne. Dans l’objectif de découvrir de nouvelles molécules antibiotiques inhibant la trans-traduction, nous avons mis au point un système de détection de la trans-traduction in vitro. Ce système est simple et rapide, basé sur la mesure de la fluorescence d’une GFP tronquée, réassemblée par un ARNtm muté. La validation du système a conduit à la détection de nouveaux composés anti-trans-traduction
This work is focused on a biological process which controls bacterial protein synthesis, trans-translation. This all-in-one process allows the rescuing of ribosomes stalled on defective mRNA, the degradation of the problematic peptides and mRNA. It is driven by two principal actors that interact with the ribosome: transfer-messenger RNA (tmRNA) and Small protein B (SmpB). In a first chapter, by a cryo-electron microscopic (cryo-EM) study, two near-atomic resolution structures, involving the ribosome and various trans-translation actors, were obtained. The first one highlights the interactions between RNase R, an enzyme responsible for mRNA degradation during trans-translation, and the bacterial ribosome. The second one corresponds to the characterization of two early trans-translation states at a near-atomic resolution. New interactions have been observed between SmpB and tmRNA H5 helix. In a second chapter, trans-translation is used as a target for the development of new antibiotic molecules. Indeed, this pathway is often necessary for bacterial survival and pathogenicity. Towards this aim, we designed and set up a new in vitro assay for high-throughput screening assays. This efficient system is based on fluorescence measurements of a GFP reassembled through trans-translation by a mutated tmRNA. This system has been validated and will be used for the discovery of new anti-trans-translation compounds

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Ivanova, Natalia. "Finding the unknowns in trans-translation." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ-bib. [distributör], 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-5756.

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Ranaei-Siadat, Seyed-Ehsan. "Structure, stabilité et interactions de l’ARNtm avant liaison au ribosome." Thesis, Paris 5, 2013. http://www.theses.fr/2013PA05P605.

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Crandall, Jacob N. "Ribosomal RNA Mutations that Inhibit the Activity of Transfer-Messenger RNA of Stalled Ribosomes." Diss., CLICK HERE for online access, 2010. http://contentdm.lib.byu.edu/ETD/image/etd3535.pdf.

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Macé, Kévin. "Le contrôle qualité de la synthèse protéique comme cible pour le développement de nouveaux antibiotiques." Thesis, Rennes 1, 2016. http://www.theses.fr/2016REN1B034/document.

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Le travail retranscrit dans cette thèse regroupe l'étude de différents processus biologiques impliqués dans la synthèse protéique bactérienne. Dans un premier chapitre, les origines de la synthèse protéique au temps du monde ARN sont traitées en guise d'introduction. Ce travail théorique se poursuit par la présentation d'une structure à haute résolution du facteur d'élongation G (EF-G) en complexe avec le ribosome par cryo-microscopie électronique à transmission (cryo-MET). Grâce aux avancées techniques de la cryo-MET, nous avons observé pour la première fois EF-G lié au ribosome en l'absence de tout inhibiteur. Cet état particulièr d'EF-G permet de visualiser une flexibilité de son doamine III. Cette étude permet aussi de rationaliser le fonctionnement de l'antibiotique acide fusidique. Nous nous sommes ensuite intéressés aux voies de sauvetage de la synthèse protéique et plus particulièrement de la trans-traduction. Ce mécanisme fascinant permet le recyclage des ribosomes bloqués sur un ARN messager défectueux. Cette voie de sauvetage est généralement vitale ou alors indispensable pour la virulence bactérienne. Nous avons réalisé une étude structurale préliminaire de la dégradation de l'ARNm défectueux durant ce processus. Après une revue traitant du sujet, nous présentons une étude de la trans-traduction comme cible pour le développement de nouveaux antibiotiques. Pour cela, nous avons mis au point un système rapporteur avec contrôle interne de l'activité trans-traductionnelle bactérienne. Après avoir mis au point ce système et validé son utilisation, nous l'avons exploité en testant des molécules ciblant la trans-traduction
The current PhD work brings together various studies linked to bacterial protein synthesis. The first chapter is about the origins of protein synthesis at the time of the RNA world. This theoretical work continues with the presentation of a high-resolution structure of the elongation factor G (EF-G) in complex with the ribosome by cryo-electron transmission microscopy (cryo-TEM). We describe for the first time EF-G bound to the ribosome in the absence of any inhibitor. This particular structure of EF-G displays a yet unseen positioning of its third domain, which becomes very flexible. This study helps to understand the way the antibiotic fusidic acid blocks translation. The work then switches to a study of trans-translation, the main rescuing system of stalled ribosomes in bacteria. Trans-translation is generally vital or at least necessary for bacterial virulence. We conducted a preliminary structural study on the way faulty mRNAs are degraded during this process. This is why we present a study of trans-translation as a target for the development of new antibiotics. For this we developed and validated a reporter system for trans-translation, which is used to screen molecules targeting trans-translation

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Ohlenroth, Matthias, and Thomas Radke. "Linux SMP." Universitätsbibliothek Chemnitz, 1998. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-199800243.

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Laaksonen, Mikael. "A reliable SMPP implementation in Erlang." Thesis, Uppsala universitet, Institutionen för informationsteknologi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-204894.

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Software failure is one of the main problems in computer systems. Especially in systems with demand for high availability, such as telecom systems. SMPP is a protocol for sending short messages between entities in the telecom network. This thesis describes the design and implementation of a highly fault tolerant and reliable SMPP server and client. The implementation is done in Erlang, a language that was designed for fault tolerance. After testing the fault tolerance, the developed software has been integrated into telecommunication systems in commercial use at Mobile Arts.

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Benjaminsen, Helle. "Business Intelligence for SMB." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for datateknikk og informasjonsvitenskap, 2011. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-14366.

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Denne oppgaven tar for seg småa- og mellomstore bedrifters (SMB) behov forBusiness Intelligence (BI), og utfordringer for slike bedrifter. Det diskutereshvordan disse bedriftene burde gåa fram, for å lykkes med BI. Det gjøresogsåa en vurdering på hvilke bedrifter som er egnet for å benytte seg avOpen Source BI-programvare.

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Glands, Paul David. "Zinc sensing by the cyanobacterial SmtB protein." Thesis, University of Newcastle Upon Tyne, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.388662.

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Chapman, Kaye E. "SmtB/ArsR proteins with unknown sensory motifs." Thesis, University of Newcastle Upon Tyne, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.442316.

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Austin, Ty (Roydrick Tyrone). "Makivism design : Social Media Participatory Design (SMPD)." Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/118500.

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Thesis: S.M. in Architecture Studies, Massachusetts Institute of Technology, Department of Architecture, 2018.
Cataloged from PDF version of thesis. "June 2018."
Includes bibliographical references (page 60).
We live in a world today where instantaneous transparency is the rule of thumb. Social media platforms such as Facebook or Linkedin have become the primary modes of communication and connectivity amongst professional and personal circles. Building Information Modeling, or BIM, is a 3D parametric modeling software. BIM visually assists architecture and engineering design teams remotely collaborate, innovate, and connect instantaneously with colleagues clients in more productive ways to create efficient construction projects. However, BIM's strengths in efficient transparency are often not extended to the principal stakeholders of any project: the community. This thesis will examine an intersectional interest known as Social Media Participatory Design (SMPD) or Makivism Design. SMPD is the integration of both 3D parametric modeling with social media. Network platforms, such as Facebook or Linkedin, are the primary modes of communication and connectivity amongst design professionals and community leaders today. By implementing SMPD into the built environment sector, community stakeholders can attain instantaneous access into the design process of a project through their favorite social media app. The primary research objective of this thesis is examine whether SMPD provides the designer, or user, the knowledge and communication they need to make the informed, transparent and inclusive design making decisions needed to collaborate on community-based projects. We will determine whether SMPD has the potential to empower those who feel marginalized and demand designers and clients alike to be more inclusive.
by Ty Austin.
S.M. in Architecture Studies

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Rocha, Carols A. (Carlos Andres Rocha Penagos). "SMPL : a network architecture for collaborative distributed services." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/33889.

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Thesis (S.M.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2005.
Includes bibliographical references (p. 85-89).
This thesis proposes a network architecture, called SMPL, for the design and development of collaboration-oriented, distributed applications over the Internet. The goal of SMPL is to enable the development of applications that easily integrate the capabilities of different types of computing resources, software platforms, and data repositories across the Internet transcending the level of a single device. SMPL proposes a new abstraction of the Internet as a network composed of services, resources, and capabilities instead of just machines. The SMPL architecture distributes resources through a peer-to-peer network of service providers. The design of SMPL encourages developers to add value to the system by facilitating the creation of new functionalities based upon compositions of the existing ones.
Carlos A. Rocha.
S.M.

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Graham, Alison Isobel. "Action and metal-specificity of SmtB/ArsR transcriptional regulators." Thesis, University of Newcastle Upon Tyne, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.427312.

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Chew, W. M. "Optimum electromagnetic design for wound components in SMPS applications." Thesis, University of Bath, 1989. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328339.

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Schmollinger, Martin. "Designing parallel algorithms for SMP clusters." [S.l. : s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=969343841.

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Puttmann, John Paul. "Spatially Targeted Activation of a SMP." University of Dayton / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1525166147319011.

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Kolář, Jan. "Motivace pracovníků ve firmě SMP CZ." Master's thesis, Vysoká škola ekonomická v Praze, 2011. http://www.nusl.cz/ntk/nusl-81623.

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The aim of this master thesis is an analysis of a motivation system in SMP CZ. The first part defines the way of a research and describes used methods. The second part focuses on theoretical knowledge, which is crucial for understanding of motivation. The biggest part is devoted to actual research of a job satisfaction of employees. In this context, possible solutions and perspectives for future development are suggested.

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Rodrigues, Rui Cláudio dos Reis. "Compact SMB chromatography for binary separation." Doctoral thesis, FCT - UNL, 2009. http://hdl.handle.net/10362/1938.

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A thesis submitted for the degree of Doctor of Philosophy
This thesis consists essentially of theoretical and experimental developments in the field of continuous chromatography using small-scale units. Continuous chromatographic separation processes based on the Simulated Moving Bed (SMB) technology were first patented and applied in 1961 for a large number of separations in the petrochemical industry and later for sugar separation. However, in the last two decades,due to the patent expiration, the process has been gaining great interest in the separation/purification of products in fine chemical and pharmaceutical industries. The conventional SMB comprises several identical columns which are serially connected in either a closed- or open-loop configuration. In order to simulate the movement of a solid bed in opposite direction to the fluid, the positions of the input and output streams are shifted downstream by one column, at fixed intervals, in the direction of fluid flow. With the development of new and efficient equipment and stationary phases, several new schemes of operating that differ from the conventional one have emerged. These include new concepts such as Varicol, ModiCon and PowerFeed processes, which rely on the periodic modulation of certain process parameters during the switching interval to enhance the efficiency of the separation. These advances are pushing the trend for units with a small number of columns, since the overall setup is more economical. However, when these newly schemes are applied in practice the process becomes more complex, because of the increased degrees of freedom that must be optimized. It is also less robust and more difficult to operate because it is more demanding on hardware. This additional complexity requires highly versatile SMB equipment, advanced optimization tools and robust control procedures. Experimental tools to experimentally reproduce the periodic state of multicolumn countercurrent chromatography with just one column are developed; they are economic and fast methods of experimentally exploring different column configurations and cyclic operation policies,ideally suited for applied research studies but may also be useful in the early stages of development, optimization, and validation of a new chromatographic separation. The feasibility of the proposed single-column system is experimentally demonstrated for several different column configurations, which include both synchronous and asynchronous port switchings and flow modulated schemes. Following the potentialities of these new operating schemes, a novel SMB system for binary separation that employs only two-columns is developed. The designed two-column process uses both the port switching and the flow rates modulation procedure. The process is very versatile since the cycle itself is optimized and adapted to the difficulty of the separation and process specifications. Furthermore, a simplified extension of the two-column setup which relies on a minimum pump number configuration and on a uniform flowrate scheme is built-up; additionally a further development on these simplified setup is applied which effectively enhances the process with only the cost of a small increase on the setup equipment. Potentialities of this new unit are illustrated comparing it to setups using the same amount of stationary phase.
Fundação para a Ciência e Tecnologia (FCT/MCTES)

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Luu, Magnus, and Johan Karlsson. "Server Message Block : En undersökning av potentiella prestandavinster mellan SMB 2.1 och SMB 3.0 i ett befintligt nätverk." Thesis, Linnéuniversitetet, Institutionen för datavetenskap (DV), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-34008.

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Examensarbetet behandlar en jämförelse av Server Message Block 3.0 och föregångaren 2.1 i ett befintligt nätverk. Jämförelsen utfördes i fyra laborationsmiljöer bestående av fyra operativsystem: Windows Server 2008 R2, Windows Server 2012, Windows 7 ochWindows 8. Sammanlagt har fyra tester utförts: Förstudie, Test 1, Test 2 och Test 3. Förstudien utfördes för att testa nätverksprestanda mellan två datorer. De andra testerna satte SMB 2.1 och SMB 3.0 på prov. I Test 1 ansågs SMB 3.0 prestera sämre än SMB 2.1, för att bekräfta resultaten kontaktades Jose Barreto på Microsoft. Barreto påstod att programvarorna Windows Defender och Windows Firewall kunde ge upphov till störningar och prestandaminskningar. Test 2 och Test 3 utfördes därför med tidigare nämnda programvaror avaktiverade. Resultaten var som tidigare varierande men kan mycket väl bero på andra faktorer som exempelvis dåligt uppdaterade nätverkskortsdrivrutiner.
The dissertation addresses the comparison of Server Message Block 3.0 and its predecessor SMB 2.1 on an existing network. The comparison was performed in four laboratory environments consisting of four operating systems: Windows Server 2008R2, Windows Server 2012, Windows 7 and Windows 8. A total of four tests were performed: Feasibility Study, Test 1, Test 2 and Test 3. The feasibility study was conducted to test the network performance between two computers while the other tests put SMB 2.1 and 3.0 to the test. In Test 1 SMB 3.0 was considered to underperform in difference to SMB 2.1, to confirm the results Jose Barreto at Microsoft were contacted. Barreto stated that the two software applications Windows Defender and Windows Firewall could cause interference and performance reductions. Test 2 and Test 3 was therefore performed with the previously mentioned software disabled. The results were as previously varied but may well be due to other factors such as poorly updated network card drivers.

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Martin, Michael Paul. "Performance measurement in the RAMP SMP facility." Thesis, Monterey, California. Naval Postgraduate School, 1989. http://hdl.handle.net/10945/26157.

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Henriksson, Joakim. "SMB : En prestandajämförelse mellan SMB1 och SMB2." Thesis, Högskolan i Skövde, Institutionen för kommunikation och information, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-5935.

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Centraliserad lagring av data är idag vanligt på företag och andra organisationer. För att användarna ska få åtkomst till informationen används kommunikationsprotokoll såsom Server Message Block (SMB). I detta arbete utvärderas de två versionerna av protokollet SMB1 och SMB2 i praktiska experiment. SMB1 har problem med nätverksfördröjning som resulterar i dålig prestanda, SMB2 utvecklades med detta i åtanke och ska därmed hantera nätverksfördröjning bättre. Utvärdering av protokollen sker praktiskt i ett antal olika experiment med olika intervall av nätverksfördröjning och därefter en analys. Resultaten visar att SMB2 effektivt åtgärdat problemen SMB1 har med nätverksfördröjning och därmed presterar betydligt bättre än föregångaren vid filöverföring.

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Chen, Yen-Ming. "RC Snubber Design using Root-Loci Approach for Synchronous Buck SMPS." Thesis, University of Waterloo, 2005. http://hdl.handle.net/10012/963.

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This thesis presents an analytical approach using Root-Loci method for designing optimum passive series RC snubbers for continuous-current synchronous buck switch mode power supply (SMPS). Synchronous buck SMPS is the most popular power converter topology found in modern consumer electronics. It offers relatively good efficiency to target the high-current and low-voltage requirements while it is also relatively inexpensive to implement. Passive series RC snubbers are simple, efficient and cost-effective open-loop equalizer circuit for synchronous buck SMPS. Its purpose is to control and to balance between the rate of rise and the overshoots of transient switching waveform in order to optimize efficiency and reliability Existing methods of RC snubber design are solely based on second-order approximation. It is investigated in this research that this approximation is highly inaccurate in SMPS applications because higher order equivalent models are required for the load path of the SMPS. The results using the RC snubbers obtained from existing method are shown to be unsatisfactory without correlation to the calculations and simulations based on second-order approximation. Optimum RC values obtained using Root-Loci approach presented in this thesis are shown to correlate to both Spice simulation and lab measurements.

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Hippold, Judith, and Gudula Rünger. "Task Pool Teams for Implementing Irregular Algorithms on Clusters of SMPs." Universitätsbibliothek Chemnitz, 2006. http://nbn-resolving.de/urn:nbn:de:swb:ch1-200600537.

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The characteristics of irregular algorithms make a parallel implementation difficult, especially for PC clusters or clusters of SMPs. These characteristics may include an unpredictable access behavior to dynamically changing data structures or strong irregular coupling of computations. Problems are an unknown load distribution and expensive irregular communication patterns for data accesses and redistributions. Thus the parallel implementation of irregular algorithms on distributed memory machines and clusters requires a special organizational mechanism for a dynamic load balance while keeping the communication and administration overhead low. We propose task pool teams for implementing irregular algorithms on clusters of PCs or SMPs. A task pool team combines multithreaded programming using task pools on single nodes with explicit message passing between different nodes. The dynamic load balance mechanism of task pools is generalized to a dynamic load balance scheme for all distributed nodes. We have implemented and compared several versions for task pool teams. As application example, we use the hierarchical radiosity algorithm, which is based on dynamically growing quadtree data structures annotated by varying interaction lists expressing the irregular coupling between the quadtrees. Experiments are performed on a PC cluster and a cluster of SMPs.

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29

Ebersson, Joel. "Design och konstruktion av laborationsutrustning till en kraftelektronikkurs." Thesis, Uppsala University, Electricity, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-131542.

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The purpose of this degree project was to build laboratory equipment for a new course in power electronics that starts this autumn 2010 at Uppsala University. The equipment is intended for student labs and it covers the most important areas of the course including rectifying, buck-/boost-converters and PWM-modulation. It is built as one sealed unit where all the electronics are built-in but visible and it has a connection board where students safely can connect the different circuits. The project has advanced from theoretical studies of circuit design, choosing of components and simulations to drawing the printed circuit board (PCB), soldering, case building, final testing and troubleshooting - basically most steps from an early idea to a final product. Measurements on the final product gave about the same results as the earlier simulations of the circuits and the result is overall satisfying.

Syftet med det här examensarbetet var att bygga laborationsutrustning till en ny kurs i kraftelektronik som börjar hösten 2010 på Uppsala Universitet. Utrustningen är avsedd för studentlaborationer och den täcker de viktigaste delarna av kursen inklusive likriktning, buck-/boost-omvandlare och pulsbreddsmodulering (PWM). Laborationsutrustningen är byggd som en sluten enhet där all elektronik är inbyggd men synlig och den har en kopplingsplatta där studenterna säkert kan koppla ihop olika kretsar. Projektet har sträckt sig från teoretiska studier inklusive kretsdesign, komponentval och simuleringar till ritande av kretskortet (PCB-kortet), lödning, byggande av höljet, sluttestning och felsökning - i huvudsak de flesta stegen från en tidig idé till en färdig produkt. Mätningar på den färdiga produkten är ganska lika de tidigare simuleringarna av kretsarna och resultatet är totalt sett tillfredställande.

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30

Wang, Yun. "Characterization of Mycobacterium tuberculosis CmtR_Mtb, a Pb(ii)/Cd(ii)-sensing SmtB/ArsR metalloregulatory repressor, and a homolog from S. coelicolor A3(2)." Texas A&M University, 2005. http://hdl.handle.net/1969.1/4406.

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The SmtB/ArsR family of prokaryotic metalloregulators are winged-helix transcriptional repressors that collectively provide resistance to a wide range of both biologically required and toxic heavy metal ions. CmtRMtb is a recently described CdII/PbII regulator expressed in M. tuberculosis that is structurally distinct from the wellcharacterized SmtB/ArsR CdII/PbII sensor, S. aureus plasmid pI258-encoded CadC. From functional analyses and a multiple sequence alignment of CmtR homologs, CmtRMtb is proposed to bind PbII and CdII via coordination by Cys57, Cys61 and Cys102 [Cavet et al. (2003) J. Biol. Chem. 278, 44560-44566]. To better understand the mechanism how CmtRMtb utilizes specific metal ions to perform transcriptional repressor function, both CmtRMtb and its homolog in S. coelicolor A3(2) (CmtRSc) were studied. We establish here that both wild-type and C102S CmtRMtb are homodimers and bind CdII and PbII via formation of cysteine thiolate-rich coordination bonds. UV-Vis optical spectroscopy and 113Cd NMR spectroscopy (ÃÂ´=480 ppm) suggest two or three thiolate donors, while 111mCd perturbed angular correlation (PAC) spectroscopy establish an unusual trigonal pyramidal coordination eometry. C102S CmtRMtb binds CdII and ZnII with only Ã¢ÂÂ 10-20 fold lower affinity relative to wild-type CmtRMtb, but Ã¢ÂÂ 100-1000-fold lower for PbII. Quantitative investigation of CmtR-cmt O/P binding equilibria using fluorescence anisotropy reveals that Cys57 and Cys61 anchor the coordination complex with Cys102 functioning as a key allosteric ligand, while playing only an accessory role in stabilizing the metal complex in the free protein. Similar metal titration experiments were carried out with a putative CmtR homolog from S. coelicolor A3(2) (CmtRSc) and a double cysteine substitution mutant C110G/C111S CmtRSc. The implications of these findings on the evolution of distinct metal sensing sites in a family of homologous proteins are discussed.

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31

黃君保 and Kwan-po Wong. "High-speed network interface for commodity SMP clusters." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B31225330.

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Wong, Kwan-po. "High-speed network interface for commodity SMP clusters." Hong Kong : University of Hong Kong, 2000. http://sunzi.lib.hku.hk/hkuto/record.jsp?B22505520.

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33

Carretero, Miguel Adrian. "Aplicação dos conceitos do SMP2 para comunicação entre sistemas legados de simulação." Instituto Nacional de Pesquisas Espaciais, 2012. http://urlib.net/sid.inpe.br/mtc-m19/2011/12.05.20.15.

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Um Simulador de Satélites é composto por modelos que representam o comportamento dos vários subsistemas de um satélite podendo ainda, incluir modelo do ambiente espacial e de estações terrenas de recepção de dados. Muitos destes modelos, em especial os do ambiente espacial, geralmente, não sofrem alterações de um simulador para outro, podendo ser reutilizados ao longo de anos, em diferentes simuladores. Entretanto, esta prática de reutilização não tem sido rotineiramente aplicada. Visando melhorar a interoperabilidade e aumentar o reúso neste tipo de aplicação, a Agência Espacial Européia (ESA) definiu o padrão Simulation Model Portability (SMP), Portabilidade de Modelos de Simulação, que orienta a estruturação de Simuladores de Satélite. O objetivo dessa dissertação é explorar a aplicabilidade dos conceitos do SMP para viabilizar a comunicação entre modelos legados de simulação. Identificados os limites na arquitetura atual do SMP foi proposta uma extensão aos mecanismos de comunicação desta arquitetura de modo a permitir a inclusão dos modelos legados a um simulador que seja conforme o SMP. Uma demonstração da solução dada ao mecanismo de comunicação proposto é feita através de um estudo de caso. Essa dissertação mostra uma solução para aplicação dos mecanismos para interoperabilidade entre modelos legados de simulação se beneficiando da padronização para reforçar o reúso de modelos e de mecanismos que dão suporte a um simulador. Entretanto, a solução ainda mantém a dependência da plataforma computacional e de uma linguagem orientada a objetos.
A Satellite Simulator is composed of a set of models that represents the behavior of the various satellite subsystems. It may also include a model of the space environment and of the ground stations. Many of these models, especially the space environment model do not change from one simulator to another and can be reused over the years. However, this is not a common practice. In order to improve interoperability and increase re-use of the models, the European Space Agency (ESA) created a standard named Simulation Model Portability (SMP) that guides the development of Satellite Simulators. The objective of this work is to explore the applicability of the concepts of SMP to enable communication between legacy simulation models. After identifying limitations in the current SMP architecture it was proposed an extension of the SMP communication mechanisms to allow the addition of legacy models to a SMP simulator. A case study was used to demonstrate the results of the proposed communication mechanism. This work also presents a computational implementation of the interoperability mechanisms between the legacy simulation models (which takes advantage from standardization) to enhance the reuse of models and mechanisms that support a simulator system. However, this solution still preserves its dependence on the computing platform and an on an object-oriented language.

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Akram, Farhan. "Gate driver solutions for high power density SMPS using Silicon Carbide MOSFETs." Thesis, Mittuniversitetet, Institutionen för elektronikkonstruktion, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-41188.

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Discrete silicon carbide (SiC) power devices have unique characteristics that outpace those of silicon (Si) counterparts. The improved physical features have provided better faster switching, greater current densities, lower on-resistance, and temperature performances. However, there is lack of suitable commercial gate drivers that are compatible for high-voltage, and high-speed devices. There has been a great research effort required for the advancement of gate drivers for high voltage SiC transistors. A drive circuit for a SiC MOSFET needs to be optimized in normal operation to give best efficiency and same drive circuit should secure the MOSFET under unsuitable conditions. To ensure the rapid switching of these advanced SiC MOSFETs, a gate driver capable of providing the high current capability is required. In this work, three different high-power-density, high-speed, and high-noise-immunity gate driver modules for 10 kV SiC MOSFET were built and optimized. Double-pulse test was developed for the dynamic characterization of SiC MOSFETs and gate drivers. This setup provided clean measurements of DUT voltage and current under well-defined conditions and correlated to simulation results. Designed gate drivers have thoroughly investigated to test and compare it with our future design. The influential parameters such as dV/dt, dI/dt, and gate driving capability of gate driver were adjusted according to the requirements. The short circuit protection test was performed to check the reliability of driver modules in worst conditions. Furthermore, a DC-DC converter was designed and tested with the advanced gate drivers. The driver modules were tested in designed converter under different load conditions and influential parameters were successfully demonstrated. The driver modules effectively helped in reducing the EMI and switching losses. These designed gate drivers and prototype converter provide all the attractive features and can be widely implemented in industrial applications for energy efficient systems.

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35

Makart, Stefan Klaus. "Enzymatic carbon-carbon bond formation integrated with SMB separation /." Zürich : ETH, 2007. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=17115.

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Wekenborg, Klaus. "Kontinuierliche Trennung von Proteinen durch nicht-isokratische SMB-Chromatographieprozesse." Aachen Shaker, 2008. http://d-nb.info/995083282/04.

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37

Guo, Shuibao. "High performance digital controller for high-frequency low-power integrated DC/DC SMPS." Lyon, INSA, 2009. http://theses.insa-lyon.fr/publication/2009ISAL0033/these.pdf.

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Bien qu'un sujet de recherché important, le contrôle numérique n'a pas encore été appliqué en pratique aux convertisseurs de tension à découpage basse-puissance. Les appareils portables sont encore conçus avec des convertisseurs de tension à boucle de contrôle analogique. Ceci est dû à la complexité de l'implémentation d'un contrôleur numérique, aux contraintes de coût et l'absente d'architecture de contrôleur ayant prouvé leur efficacité pour de hautes fréquences de découpage. Les compromis entre performances, consommation, coût silicium limitent encore le développement des contrôleurs numériques. Les outils de développement efficaces existent pour concevoir des structures de contrôle numérique dans le contexte de la haute intégration (VLSI), dont des ASICs et des FPGAs. Il est plus commode d'aborder la conception de boucles de contrôles numériques dans l'environnement des régulateurs de tension à découpage pour les circuits intégrés sur batterie. Les travaux dans ce contexte sont généralisables à celui des FPGAs et à plus large échelle à des dispositifs de conversion d'énergie continue de plus forte puissance. L'objet des travaux de thèse concerne l'exploitation de diverses architectures des blocs constituants un contrôleur numérique : les lois de commande et la traduction en largeur d'impulsion des décisions en temps-réel du contrôleur (Digital pulse-width modulation). Par ailleurs, faute d'un accès matériel suffisant à une vérification expérimentale sous la forme d'ASICs, les résultats concernent en premier lieu la méthodologie de développement et la vérification couvre un grand nombre de besoins industriels et prépare la perspective de travaux dans un contexte d'intégration ultime basse puissance
Despite being a popular research topic, digital control is still seldom applied in practical low-power high-frequency integrated SMPS converters. Phones, PDAs and music/video players are still mainly designed with analog PWM control inside the voltage regulator blocks. This is mainly due to the apparent complexity of implementation, cost constraint and absence of digital controller architectures that can support operation at switching frequencies significantly higher than 1MHz with low-power consumption features. Broader acceptance of digital techniques in low-power high-frequency SMPS is still hampered by practical problems of the combination of cost issues, trade-off performances and power consumption. However, with the rapid development of Very Large-Scale Integration (VLSI) technologies and CMOS manufacturing technique, and associated with their design tools in the last decade, it is now very possible to realize the high performance digital control in power electronics system by high-speed low-power digital devices (FPGA, ASIC, etc). With these advantages, the implementation of digital controller has become more feasible for low-power high-frequency SMPS design in portable electronics applications. The research interest of the thesis is to explore practical ways of incorporating advantages of digital control in practical implementation, investigates issues of digital controller implementation at lower power levels, gives detailed guidelines for digital controller design and hardware selection, and proposes new hardware solutions for the main functional digital controller blocks. Two main objectives of this work focus the implementation of high-resolution high-frequency digital PWM (DPWM) and high-performance digital control algorithms for SMPS in FPGA-based realization

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38

Kotte, Hari Babu. "High Speed (MHz) Switch Mode Power Supplies (SMPS) using Coreless PCB Transformer Technology." Licentiate thesis, Mittuniversitetet, Institutionen för informationsteknologi och medier, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-13964.

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The most essential unit required for all the electronic devices is the Power Supply Unit (PSU). The main objective of power supply designers is to reduce the size, cost and weight, and to increase the power density of the converter. There is also a requirement to have a lower loss in the circuit and hence in the improvement of energy efficiency of the converter circuit. Operating the converter circuits at higher switching frequencies reduces the size of the passive components such as transformers, inductors, and capacitors, which results in a compact size, weight, and increased power density of the converter. At present the switching frequency of the converter circuit is limited due to the increased switching losses in the existing semiconductor devices and in the magnetic area, because of increased hysteresis and eddy current loss in the core based transformer. Based on continuous efforts to improve the new semi conductor materials such as GaN/SiC and with recently developed high frequency multi-layered coreless PCB step down power transformers, it is now feasible to design ultra-low profile, high power density isolated DC/DC and AC/DC power converters. This thesis is focussed on the design, analysis and evaluation of the converters operating in the MHz frequency region with the latest semi conductor devices and multi-layered coreless PCB step-down power and signal transformers. An isolated flyback DC-DC converter operated in the MHz frequency with multi-layered coreless PCB step down 2:1 power transformer has been designed and evaluated. Soft switching techniques have been incorporated in order to reduce the switching loss of the circuit. The flyback converter has been successfully tested up to a power level of 10W, in the switching frequency range of 2.7-4 MHz. The energy efficiency of the quasi resonant flyback converter was found to be in the range of 72-84% under zero voltage switching conditions (ZVS). The output voltage of the converter was regulated by implementing the constant off-time frequency modulation technique. Because of the theoretical limitations of the Si material MOSFETs, new materials such as GaN and SiC are being introduced into the market and these are showing promising results in the converter circuits as described in this thesis. Comparative parameters of the semi conductor materials such as the vi energy band gap, field strengths and figure of merit have been discussed. In this case, the comparison of an existing Si MOSFET with that of a GaN MOSFET has been evaluated using a multi-layered coreless PCB step-down power transformer for the given input/output specifications of the flyback converter circuit. It has been determined that the energy efficiency of the 45 to 15V regulated converter using GaN was improved by 8-10% compared to the converter using the Si MOSFET due to the gate drive power consumption, lower conduction losses and improved rise/fall times of the switch. For some of the AC/DC and DC/DC applications such as laptop adapters, set-top-box, and telecom applications, high voltage power MOSFETs used in converter circuits possess higher gate charges as compared to that of the low voltage rating MOSFETs. In addition, by operating them at higher switching frequencies, the gate drive power consumption, which is a function of frequency, increases. The switching speeds are also reduced due to the increased capacitance. In order to minimize this gate drive power consumption and to increase the frequency of the converter, a cascode flyback converter was built up using a multi-layered coreless PCB transformer and this was then evaluated. Both simulation and experimental results have shown that with the assistance of the cascode flyback converter the switching speeds of the converter were increased including the significant improvement in the energy efficiency compared to that of the single switch flyback converter. In order to further maximize the utilization of the transformer, to reduce the voltage stress on MOSFETs and to obtain the maximum power density from the power converter, double ended topologies were chosen. For this purpose, a gate drive circuitry utilising the multi-layered coreless PCB gate drive transformer was designed and evaluated in both a Half-bridge and a Series resonant converter. It was found that the gate drive power consumption using this transformer was less than 0.8W for the frequency range of 1.5-3.5MHz. In addition, by using this gate drive circuitry, the maximum energy efficiency of the series resonant converter was found to be 86.5% with an output power of 36.5W.

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39

Köster, Jeanette. "SMB i kommunal detaljplanering : Checklistor som inledande metodik för miljöbedömning." Thesis, Karlstad University, Division for Environmental Sciences, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-72.

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För att uppnå en god bebyggd miljö, är det viktigt att integrera miljöhänsyn tidigt i planeringsprocesser. Insikten om detta ledde till ett nytt EG-direktiv, det s k SMB-direktivet om miljöbedömningar av planer och program som syftar till att främja en hållbar utveckling. Direktivet har implementerats i den svenska lagstiftningen och innebär, för den kommunala detaljplaneringen, framförallt att en inledande påverkansbedömning måste genomföras för att avgöra ifall planförslaget kan antas ha en betydande miljöpåverkan och därmed behöver genomgå en hel miljöbedömning. Nya tillvägagångssätt behövs för många kommuner i och med lagändringarna som innebär att förslagen måste bedömas utifrån fastställda miljökriterier.

Den här studien undersöker vilken typ av miljökrav och bedömningskriterier bör ingå i en metodik för att avgöra behovet av miljöbedömning tidigt i en planprocess och huruvida användandet av checklistor är lämpligt. Studien tyder på att checklistor fungerar bra som metodik i sammanhanget. Fördelarna tycks klart överväga nackdelarna. Dessutom analyseras vad en påverkansbedömning bör innehålla och ett förslag på en checklista presenteras. Det framkom bl a att även andra aspekter än de i MKB-förordningen framhållna bedömningskriterierna bör ingå samt att andra hållbarhetsprinciper än ekologiska och fysiska

t ex folkhälsa och samhällsekonomi är viktiga. För att utforma ett förslag på en checklista användes även goda exempel från befintliga checklistor från kommunerna Gävle och Norrköping.

To reach a good built environment, it is important to integrate environmental concerns early in the societal planning processes. The insight of this led to a new EC-directive, a k a the SEA- directive, on the assessment of the effects of certain plans and programmes on the environment, which aims to promote a sustainable development. The directive has been implemented into the Swedish legislation and involves, for municipal detail planning, in particularly that an introductory impact assessment has to be made in order to determine whether a plan can be assumed to cause a significant environmental impact. In that case an entire environmental assessment has to be done. New procedures for municipals have to be developed due to the changes in legislation, which for example implies that the projects must be assessed from established environmental criteria.

This present study investigates which type of environmental restrictions and criteria that is required from a methodology used to decide whether an early impact assessment is needed. The potential use of checklists is especially analysed. The study suggests that checklists are suitable in this context. The advantages clearly seem to overweigh the disadvantages.

Furthermore an analysis of what impact assessment should include is made and a proposal of a checklist is presented. It was obvious that aspects other than those in the Swedish EIA-regulation should be included and also that other than ecological and physical principles of sustainability are important, for example economy and public health. To create a new proposal for a checklist, good examples were also used from already existing checklists. Those were from the municipals of Gävle and Norrköping.

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40

Morken, Anders, and Per Ottar Ribe Pahr. "Apache Derby SMP scalability : Investigating limitations and opportunities for improvement." Thesis, Norwegian University of Science and Technology, Department of Computer and Information Science, 2007. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-8734.

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This report investigates the B-Tree access method of Apache Derby. Apache Derby is an open source Java database system. The detailed focus of the report is on performance aspects of the Derby page latch implementation. Our focal point is the interaction between the B-Tree access method and page latching, and the impact of these components on the ability of Derby to scale on multiprocessor systems. Derby uses simple and in the single-threaded case inexpensive exclusive-only page latches. We investigate the impact on scalability of this design, and contrast it with a version of Derby modified to support both shared read-only and exclusive page access for lookups in index structures. This evaluation is made for single-threaded as well as multi-threaded scenarios on multiprocessing systems. Based on analyses of benchmark results and profiler traces, we then suggest how Derby may be able to utilize modern Java locking primitives to improve multiprocessor scalability.

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McQuay, Stephen Mardson. "SMB-Interp: an N-Th Order Accurate, Distributed Interpolation Library." BYU ScholarsArchive, 2011. https://scholarsarchive.byu.edu/etd/2837.

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The research contained herein yielded an open source interpolation library implemented in and designed for use with the Python programming language. This library, named smbinterp, provides an interpolation to an arbitrary degree of accuracy. The library is parametric in that is can take input from the user to adjust the underlying interpolation mechanism. The characteristics and behavior of the library according to the adjustment of these parameters is presented herein, as well as the results of a mesh resolution study depicting the accuracy obtained by the library. The smbinterp library was designed with parallel computing environments in mind. The library includes modules that allow for its use in high-performance computing environments. These modules were implemented using built-in Python modules to simplify deployment. This implementation was found to scale linearly approximately 180 participating compute processes. The smbinterp library was designed to be mesh agnostic. A plugin system was implemented that allows end users to conveniently and consistently present their numerical results to the library for rapid prototyping and integration. Two plugins are provided as examples and for documentation of the plugin mechanism.

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42

Liu, Boya. "Comparison of Foaming Properties between Chelated Reconstituted SMP and Caseinates." DigitalCommons@CalPoly, 2016. https://digitalcommons.calpoly.edu/theses/1648.

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Caseinate powders have been well accepted because of their foaming properties. In this study, 10% solution of reconstituted skim milk powder (SMP) chelated with sodium hexametaphosphate (SHMP) and trisodium citrate (TSC) at 1 mEq, 50 mEq, and 100 mEq were prepared to conduct a comparison with sodium caseinate, potassium caseinate, and calcium caseinate solutions. Foamability, foam stability as well as the preferential locations of αs-casein, β-casein and !-casein in their foams were analyzed. It was hypothesized that the foamability, foam stability and the preferential locations of these three caseins in the milk foams are different from treatment to treatment. Milk foam was generated with an air- injection method at a flow rate of 0.30 L/M for 18 seconds. Foam stability was measured through half-life method. The foam composition was quantified with sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) method. Analysis of Variance (ANOVA) test results concluded that there were no significant differences detected in foamability (p>0.05). On the other hand, foam stability differed significantly among the treatments. Foams of reconstituted SMP-treated with 1 mEq SHMP and TSC were significantly more stable compared to other treatments (p < 0.05), β-casein (p>0.05) and !-casein (p>0.05). In conclusion, the addition of calcium chelating salts might increase the foamability to the same level as caseinate solutions. Furthermore, the study proved that the combination of calcium chelating salts and chelator levels is able to alter the foam stability.

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Kubáčová, Jana. "Souhrnné modely hodnocení a jejich aplikace v SMP, a. s." Master's thesis, Vysoká škola ekonomická v Praze, 2007. http://www.nusl.cz/ntk/nusl-1449.

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Práce se zaměřuje na souhrnné modely hodnocení, které umožňují z globálního hlediska posoudit finanční situaci podniku.Jádro tvoří bonitní a bankrotní modely jako Altmanův model, indexy IN, Tafflerův model, Kralickův Quicktest, Tamariho model, Index bonity, Grünwaldův index bonity, Bilanční analýza podle R. Douchy a Beermanova diskriminační funkce, práce dále obsahuje i Pollakovu metodu hodnocení vitality podniku. Smyslem bylo zhodnotit vývoj finančního zdraví podniku Severomoravská plynárenská, a. s. a provést komparaci výsledků aplikovaných modelů.

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44

Hoagland, Richard W. "Switchmode Power Supply Miniaturization with Emphasis on Integrated Passive Components on Prefired High Performance Ceramic Substrates." Diss., Virginia Tech, 1999. http://hdl.handle.net/10919/28732.

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This Dissertation is a study of Switched Mode Power Supply (SMPS) miniaturization and how to effectively use the available technologies to achieve the ultimate goal of a reduced size without loss of functionality while maintaining a cost effective design. This research investigates several methods used to obtain low loss, highly compact power supplies. Within these constraints, the Dissertation investigates the issues of design, materials, and cost in order to design and achieve these miniaturized power supplies. This research addresses high performance ceramic, passive component integration. Three key issues; electrical characterization, thermal analysis and simulation, and material characterization, are examined in this work. Thick film passive components (capacitors and resistors) on AlN have been developed. Also, guidelines for the design implementation and steps necessary to integrate these passive components on prefired alumina (Al2O3) and aluminum nitride (AlN) ceramic surfaces, for power electronic applications, have been generated. The use of aluminum nitride, as a high performance ceramic substrate and the resulting issues concerning compatible inks, have been investigated. Since a sizable amount of heat is generated by power electronic circuits, the integrated components are analyzed with respect to tolerance and degeneration over a range of temperatures and frequencies. Thick film capacitors on the order of 120pF/mm2 with breakdown voltage ratings of 250V have been developed on prefired AlN. Resistors were developed with impedances ranging from 10W to 10MegW. Thermal measurements, of these resistors, show that the thermal conductivity of the aluminum nitride with passivation layer is two to three times that of alumina. Several versions of a typical SMPS boost circuit have been generated using Direct Bond Copper (DBC) on ceramic, Insulated Metal Substrate (IMS), Printed Circuit Boards (PCB), and prefired ceramic thick film technology. The integrated passive components developed are applied on prefired ceramic versions and compared to the DBC, IMS and PCB versions. A small daughter board consisting of the boost circuit control is introduced to further supplement miniaturization and reduce cost. The daughter board uses thick film technology with integrated thick film resistors. The design of the mother board, which houses the power boost section,can be designedand implemented on virtually any type of substrate (PCB, DBC, IMS, or conventional thick film). The fabrication and testing of each version is reported in this work.
Ph. D.

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Atluru, Sri Harshavardhan. "Prototype Smart Machine Supervisory System." University of Cincinnati / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1243367813.

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Kelm, Jonathon. "Modeling and Control Strategies for Multiprocess Arc Welding Power Sources." Case Western Reserve University School of Graduate Studies / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=case1574659504446931.

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Gibson, Courtney R. "Impact of communication layer performance on shared virtual memory protocols for clusters of SMPs." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0020/MQ53432.pdf.

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Chauveau, Cyril. "Non-isocyanate polyurethanes, polyamides and silyl modified polymers synthesized by olefin metathesis : alternative solutions to polyurethane adhesives." Thesis, Rennes 1, 2018. http://www.theses.fr/2018REN1S127.

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Les polyuréthanes (PUs) sont utilisés comme adhésifs depuis des décennies, mais l’utilisation d’isocyanates durant leur synthèse les place aujourd’hui dans la visée de nouvelles réglementations. Dans ces travaux, nous décrivons trois technologies alternatives potentielles aux Pus, basés sur la métathèse d’oléfines. La première technologie repose sur la synthèse de polyuréthanes sans isocyanates (NIPUs) à partir de motifs carbonate de vinylène (VC). Des polyoléfines VC2-téléchéliques ont été synthétisées par polymérisation par ouverture de cycle par métathèse / métathèse croisée (ROMP/CM) de cyclooléfines en présence d’un agent de transfert (CTA) de type VC. Cependant, la polyaddition avec une diamine a mis en évidence des reactions secondaires empêchant d’obtenir le matériaux désiré. La seconde technologie considérée est la synthèse de polyamides (PA). Des polyoléfines diazlactone (AZL)2-téléchéliques ont été synthétisées par ROMP/CM en presence d’un CTA de type AZL, puis ouvertes par une diamine. Des PAs ont ainsi été obtenus avec succès, mais en faibles quantités, ne permettant pas d’étudier leurs propriétés mécaniques ou adhésives. La dernière approche utilise les polymères silylés (SMPs). Trois types de SMPs ont été synthétisés par diverses stratégies de métathèse : des polypropylèneglycols (PPGs), des copolymères polycyclooctène (PCOE)/PPG et des copolymères polybutadiène (PBD)/PPG. La polycondensation de ces SMPs par différents systèmes catalytiques a été étudiée, ainsi que les propriétés mécaniques et adhésives des matériaux résultants. Parmi ceux-ci, les copolymères PCOE/PPG SMPs ont démontré de remarquables propriétés mécaniques et adhésives, meilleures que la plupart des SMPs commerciaux d’aujourd’hui
Polyurethanes (PUs) have been used as adhesives for decades, but the toxic isocyanates needed for their synthesis is now on the scope of regulations. In this work, we describe three potential alternative technologies to classic PUs, based on a powerful polymerization tool: olefin metathesis. The first technology relies on the synthesis of nonisocyanate polyurethanes from vinylene carbonate (VC) functionalities. Telechelic VC polyolefins were synthesized by ring-opening metathesis polymerization/cross-metathesis (ROMP/CM) of cycloolefins with a VC chain-transfer agent (CTA). However, polyaddition attempts with a diamine evidenced side-reactions, preventing the isolation of the expected material The second technology considered is the synthesis of polyamide (PA). Following a similar strategy, telechelic azlactone (AZL) polyolefins were synthesized by ROMP/CM of cycloolefins with an AZL CTA, then, were subsequently opened by a diamine. PA were successfully obtained through this strategy, however in small quantities, thus, no mechanical nor adhesive tests were carried out. The last technology uses silyl modified polymers (SMPs). Three type of SMPs were synthesized, using diverse olefin metathesis strategies : polypropylene (PPG), polycylooctene (PCOE)/PPG copolymers and polybutadiene (PBD)/PPG copolymers. Curing of the trimethoxysilyl or triethoxysilyl groups inside these SMPs was studied using different catalytic systems, as well as the mechanical and adhesive properties of the materials obtained. Among them, PCOE/PPG copolymers displayed remarkable good mechanical and adhesive properties, better than the majority of commercial SMPs available today

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Karlsson, Fredrik, and Johan Frid. "Monitorering av Bulk-SMS." Thesis, University of Kalmar, School of Communication and Design, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:hik:diva-1970.

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SMS-trafiken världen över ökar hela tiden och användningsområdena blir fler. Flera företag har börjat använda SMS som ett medium att kontakta sina kunder, de allra vanligaste brancherna som utnyttjar detta är banker, logistikföretag och läkarmottagningar. När ett företag vill SMSa ut till sina kunder så går SMSet via en aggregatör som har kontakter med flera operatörer. En aggregatörs framgång är beroende av att så många SMS som möjligt kommer fram, för det är på det de tjänar pengar. Denna rapport utreder därför på vilket sätt man kan mäta kvalité på SMS-utskick hos en aggregatör och med kvalité avses leveranssäkerhet, leveranstid och genomströmningshastighet. Arbetets första delar handlar om vad en aggregatör gör och vad kvalité är för en aggregatör, samt de tekniska bitarna som finns kring SMS såsom GSM och SMPP. Den data som har analyserats kommer ifrån en databas hos en aggregatör och tillsammans med vetskapen ifrån bakgrundsarbetet så har resultatet blivit åtta stycken olika mätningar som tillsammans mäter de kvalitéaspekter en aggregatör har. Med de mätmetoder som presenteras i detta arbete är det fullt möjligt att med ett monitoreringsverktyg få överblick av SMS-trafiken hos en aggregatör.

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Dervishi, Erisa. "Evaluate the benefits of SMP support for IO-intensive Erlang applications." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-101459.

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In the recent years, parallel hardware has become the mainstream standard worldwide. We are living in the era of multi-core processors which have improved dramatically the computer’s processing power.The biggest problem is that the speed of software evolution went much slower, resulting in microprocessors with features that software developers could not exploit. However, languages that support concurrent programming seem to be the solution for developing effective software on such systems. Erlang is a very successful language of this category, and its SMP (Symmetric Multi Processing) feature for multi-core support increases software performance in a multi-core environment. The aim of this thesis is to evaluate the benefits of the SMP support in such an environment for different versions of the Erlang runtime system, and for a very specific target of Erlang applications, the Input/Output-intensive ones. The applications chosen for this evaluation (Mnesia,and Erlang MySql Driver), though being all IO bound, differ from the way they handle the read/write operations from/to the disk. To achieve the aforementioned goal, Tsung, an Erlang-written tool for stressing databases and web servers, is adapted for generating the required load for the tests. A valuable contribution of this thesis is expanding Tsung’s functionalities with a new plugin for testing remote Erlang nodes and sharing it with the users’ community. Results show that SMP helps in handling more load. However, SMP’s benefits are closely related to the application’s behavior and SMP has to be tuned according to the specific needs.

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Dissertations / Theses on the topic 'SmpB'

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