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1
Benito, Miguel. "Better consistency of the UDC system moving Medicine from section 61 to section 4." UDC Consortium, 2007. http://hdl.handle.net/10150/105244.
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Over 45 years ago it was decided to move the class 4 for Language to the section 8 together with Literature. Since then class 4 has not been used. A recent master thesis at the school of librarianship in Boras , â UDC, A Proposal to Basic Class 4â by Fredrik Hultqvist, (Magisteruppsats; 2006:39) proved the possibility of moving Medicine from the
section 61 to the empty class 4. This is not a new idea, but has never been implemented. Reasons are given to support this proposal, based on the need to find a better collocation of the subject while at the same time providing a solution for shorter notations.
2
Marais, Elizabeth Maria 1945. "Taxonomic studies in Pelargonium, section Hoarea (Geraniaceae)." Thesis, Stellenbosch : Stellenbosch University, 1994. http://hdl.handle.net/10019.1/58560.
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Thesis (PhD)--Stellenbosch University, 1994.ENGLISH ABSTRACT: Fifty nine species were studied in this taxonomic treatment of section Hoarea (Sweet) DC. of the genus Pelargonium L'Herit., which was last revised by Knuth in 1912. The majority of species occur in the winter rainfall area of the south-western Cape, but some species occur in the eastern Cape, a region of winter and summer rainfall. A few species also occur in the summer rainfall area in the central Karoo. Morphological, leaf anatomical, palynological and geographical data were studied in order to delimit the taxa and to determine their relationships. Eight new species were described and several name changes were made. Diagnostic features of the section are the regularly or turnip-shaped tubers with numerous dark brown peeling tunics or periderms and apically a short flattened stem from which the leaves and scape emerge. The zygomorphic flowers are almost sessile, because the pedicels are very short (0,5--1 mm) and the hypanthia long (6--100 mm). A large variation occurs in leaf form and floral structure, and the section is divided in 14 different floral groups, mainly based on the structure of the androecium and the tectum of the pollen grains, although petal form and size are also considered in clustering the species. Section Hoarea with its deciduous geophytes and sometimes extremely zygomorphic flowers, exhibits advanced morphological characters. Because of the large variation in the structure of the androecium, pollination biology was probably one of the major driving forces in the evolution of the section, and the annual rainfall plays an important role in the distribution patterns of the different species.
AFRIKAANSE OPSOMMING: Neen en vyftig spesies is bestudeer in hierdie taksonomiese ondersoek van seksie Hoarea (Sweet) DC. van die genus Pelargonium L'Herit., wat laas deur Knuth (1912) hersien is. Die meerderheid van die spesies kom in die winterreenstreek van die suidwes Kaap voor, maar sommige spesies word ook in die Oos-Kaap, wat 'n winter- en somerreenstreek is, aangetref. Enkele spesies kom in die somerreenstreek van die sentrale Karoo voor. Morfologiese, blaaranatomiese, palinologiese en geografiese data is bestudeer om die verskillende taksons af te baken, en terselfdertyd verwantskappe tussen die onderskeie spesies te bepaal. Agt nuwe spesies is beskryf en verskeie naamsveranderinge is gemaak. Diagnostiese kenmerke van die seksie is die reelmatiggevormde of raapvormige wortelknol met verskeie afskilferende donkerbruin periderms en apikaal 'n verkorte stingel waaruit blare en 'n bloeispil groei. Die sigomorfe blomme is byna sittend, aangesien die blomstele uiters kort is (0,5--1 mm) en die hipantiums relatief lank (6-- 100 mm). 'n Groot variasie in blaarvorm en blomstruktuur kom voor, en die seksie word in 14 verskillende blomvorms verdeel. Hierdie blomvorms is hoofsaaklik gebaseer op die struktuur van die andresium en tektum van die stuifmeelkorrels, alhoewel kroonblaarvorm en -grootte ook 'n rol gespeel het in die onderverdeling van die seksie. Seksie Hoarea met sy bladwisselende geofiete en soms uiters sigomorfe blomme, vertoon gevorderde morfologiese kenmerke. Die groot variasie in die struktuur van die andresium dui op 'n moontlike prominente rol wat die bestuiwingsbiologie gespeel het in die evolusie van die seksie, en die jaarlikse reenval speel 'n belangrike rol in die verspreidingspatrone van die verskillende spesies.
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Colais, Paola <1975>. "Validity of Robson Ten Group Classification System for comparative evaluation of caesarean section." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/1688/.
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Venter, Eben Kruger. "The Caesarean Section rate at Mowbray Maternity Hospital: Applying Robson's Ten group classification system." Master's thesis, University of Cape Town, 2018. http://hdl.handle.net/11427/29234.
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Background
The United Nations (UN) aims to reduce the maternal mortality ratio (MMR) and improve access to reproductive health services. Caesarean sections (CS) are known to be associated with a raised mortality rate by a factor of 2.8 in addition to the raised morbidity rate (OR 3.1; 95% CI 3.0-3.3) compared to vaginal deliveries (VD). Globally, there has been a concerning trend in the caesarean section rate (CSR), rapidly increasing since the 1970’s, with some countries reporting CS rates as high as 40.5%. South Africa has a CSR of 25.7%, which is higher than the suggested rate by the World Health Organization (WHO) of 15%; a rate above which the WHO suggests no maternal and fetal benefit exists. Robson introduced a universal classification system for caesarean sections with 10 totally inclusive and mutually exclusive groups. Horak made use of the ten group classification system (TGCS) to calculate the CSR at Mowbray Maternity Hospital (MMH) and its referring midwife obstetric units (MOU) for 2009, and reported it as 20.7%. Since the completion of her study, the referral routes to MMH have changed and the management of HIV-associated illnesses has markedly improved. A period of 7 years has elapsed and it was thought to be an optimal time to repeat a review of the CSR and compare it with the rates from 2009. Objectives The study aims to calculate the CSR for MMH from January 2016 to June 2016. Analyses of the CSR within each Robson group will be done and compared to the rates from 2009. This will allow us to make recommendations, if appropriate, aimed at reducing the CSR.
Methods
A retrospective, observational study was performed at MMH in Cape Town. Data was collected from birth registers for January 2016 – June 2016. All women who delivered, including all caesarean sections and vaginal births, were entered into the study, provided the newborn was viable with a birth weight >500g. Parameters were recorded onto an electronic and password-protected Microsoft Excel® spreadsheet and were used to classify deliveries according to the Robson Classification system. To allow for comparison with Horak’s study, deliveries at MMH for January 2009 – June 2009 were selected and analyzed. All the data was analyzed with STATA software and presented in various graphical formats. Ethics approval was obtained from University of Cape Town’s Human Research Ethics Committee (HREC Ref: 539/2016).
Results
There were 4727 deliveries from January to June 2016, of which 2472 were vaginal births and 2255 were caesarean sections, giving rise to a CSR of 47.70% (95% CI 46.28- 49.13). Of all the caesarean sections performed, 62.7% were primary caesarean sections and 37.3% were repeat caesarean sections. Nulliparous women, compared to multiparous women without a history of a prior CS, were at higher risk for a CS if in spontaneous labour (OR 2.02; 95% CI 1.71-2.38) and if induced (OR 2.75; 95% CI 2.13- 3.53). Group 5 (women with a previous CS), with a CSR of 85.34% (95% CI 82.82-87.61) made the greatest contribution to the overall CSR. The overall CSR from January to June 2009 was 44.10% (95% CI 42.63-45.57), calculated from 4379 deliveries. There was a statistically significant increase in the CSR of 3.60% from 2009 to 2016. A similar significant increase was observed in the respective CS rates of Group 1 (5.59%), Group 2 (11.63%) and Group 10 (8.73%). Group 4 was the only group with a statistically significant decrease of 4.48% in its CSR. An additional 308 labour inductions were performed in 2016, however, women in 2016 were statistically significantly less likely to be successful in a vaginal delivery (OR 0.67; 95% CI 0.55-0.81 p<0.001) compared to women in 2009.
Conclusion
A CSR of 47.70% is acceptable for a secondary level hospital such as MMH. This figure is elevated, but appropriate, as the referral units that perform only low risk vaginal deliveries are excluded. A surge in the number of repeat caesarean sections performed and lower success rates for labour inductions were mostly responsible for the rise. Primary caesarean sections performed on patients directly result in a higher risk patient profile in the future, coupled with more repeat caesarean sections in subsequent pregnancies. This is supported by a 17.5% prevalence of previous CS in women in 2009 as opposed to the 20.79% of women with a prior CS in 2016. This study shows that a CS in the index pregnancy has sizeable effects on the care of a woman in subsequent pregnancies. This places more strain on the health system and ultimately affects service delivery to all patients. Theoretically it is possible to explore changes in management to curb the ever-increasing CSR, but one has to consider if such changes is acceptable and appropriate to the setting of MMH and the population it serves.
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Clark, Shawn Meredith. "A revision of the section Scelidites in the Western Hemisphere (Coleoptera: Chrysomelidae) /." The Ohio State University, 1987. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487584612163441.
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Bayle, Lionel. "Classification des varietes projectives de dimension trois dont une section hyperplane est une surface d'enriques." Paris 11, 1992. http://www.theses.fr/1992PA112012.
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Une variete de fano plonge au moyen de son systeme anticanonique est une variete projective dont les sections hyperplanes sont des surfaces k3. Il est donc naturel de vouloir classifier les varietes algebriques projectives de dimension trois dont une section hyperplane generale est une surface d'enriques. C'est le sujet de cette these. Il s'agit d'un probleme ancien, ayant fait l'objet de travaux depuis les annees trente. Au debut de cette these nous demontrons que toute variete solution, w, est le quotient d'une variete de fano x par une involution ayant un nombre fini de points fixes. Ceci simplifie considerablement le probleme, car les varietes de fano sont en nombre fini. Ensuite nous prouvons par des arguments generaux, que la plupart des varietes de fano ne peuvent pas etre munies d'une involution ayant un nombre fini de points fixes. Puis nous etudions les involutions sur les vingt-neuf varietes restantes. Enfin, nous determinons parmi les paires formees d'une variete de fano et d'une involution celles qui donnent une solution. Nous obtenons ainsi une classification complete des varietes presque lisses dont un diviseur ample est une surface d'enriques et parmi ces varietes, nous donnons la liste de celles qui sont solutions du probleme pose
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Deveaux, Virginie. "Etude de la diversité génétique et inférence de liens phylogénétiques au sein de la section Mentha (Lamiaceae)." Saint-Etienne, 2002. http://www.theses.fr/2002STET4011.
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La taxonomie des menthes est très complexe du fait de leur polymorphisme morphologique, de leur capacité à s'hybrider et de leur domestication. La diversité génétique et les liens phylogénétiques ont été établis à l'intérieur de la section Mentha sur une collection de 62 accessions d'origines géographiques diverses, représentant les 4 espèces légitimes (M. Suaveolens L. , M. Longifolia (L. ) Huds. , M. Aquatica L. , M. Arvensis L. ) et les 3 hybrides les plus cultivés (M. Spicata L. , M. X piperita L. , M. X gracilis L. ). Les méthodes d'empreintes génétiques AFLP (Amplified Fragment Length Polymorphism) et ISSR (Inter Simple Sequence Repeat) ont permis un typage par espèce en accord avec la classification actuelle et mettent en évidence le potentiel génétique de chaque espèce ainsi que les liens de parentés entre hybrides et espèces légitimes. Le séquençage d'ADN chloroplastique (intron trnL, espaceurs intergéniques trnL-trnF, psbA-trnH) révèle plusieurs haplotypes chez certaines espèces. Les séquences ITS (Internal Transcribed Spacers 1 et 2) montrent un polymorphisme intra et interspécifique et révèlent divers modes d'évolution des génomes polyploi͏̈des et hybridesThe taxonomy of mints is complex because of their high morphological polymorphism, their ability to hybridize and their domestication. Genetic diversity and phylogenetic relationships of the section Mentha were established within a collection of 62 accessions of different geographical origins, representing the 4 legitimate species (M. Suaveolens L. , M. Longifolia (L. ) Huds. , M. Aquatica L. , M. Arvensis L. ) and the 3 most cultivated hybrids (M. Spicata L. , M. X piperita L. , M. X gracilis L. ). The AFLP (Amplified Fragment Length Polymorphism) and ISSR (Inter Simple Sequence Repeat) DNA fingerprinting methods were performed. The results allow us to identify each species and are in accordance with the present classification. On the other hand, they assess the genetic potential of each species and the relationships between hybrids and legitimate species. The non-coding chloroplastic DNA (trnL intron, intergenic spacers trnL-trnF, psbA-trnH) shows several haplotypes within some species. The ITS (Internal Transcribed Spacers 1 and 2) sequences display intra and interspecific polymorphism and give information about evolution of polyploids and hybrids
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Oberlander, Kenneth. "A molecular phylogenetic assessment of Oxalis L. section Angustatae subsection Lineares using trnL-trnF sequence data." Thesis, Stellenbosch : Stellenbosch University, 2003. http://hdl.handle.net/10019.1/53251.
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Thesis (MSc)--Stellenbosch University, 2003.ENGLISH ABSTRACT: The phylogenetic relationships and taxonomic status of South African Oxalis L. species are highly unresolved, both regionally and with regard to precise placement within the genus as a whole. Studies based exclusively on morphological and palynological characteristics have hitherto proved only partially successful in resolving natural groupings among the indigenous taxa of the region. Recent studies involving a few native taxa have indicated the plastid trnL-trnF non-coding DNA region as useful for the purposes of reconstructing phylogenetic relationships within the genus. The present study addressed the taxonomic monophyly and relationships of the highly unresolved section Angustatae subsection Lineares, using DNA sequence data. The phylogenetic reconstruction of southern African Oxalis species renders five of the subsections of section Angustatae sensu Salter (1944) polyphyletic, three of them conclusively so. The members of subsection Lineares are split between three clades, two of them with strong bootstrap support. None of these three clades consists exclusively of species of subsection Lineares. Likewise four of the seven assemblages of related taxa within subsection Lineares sensu Salter (1944) are not retrieved as monophyletic. Pollen data sensu Dreyer (1996) supports the clades retrieved in this study, whereas very few morphological characters could be plotted as potential synapomorphies for these clades. The resultant phylogenetic reconstruction thus supports palynological data of this subsection, and indicates the urgent need for a revision of the current morphological classification of Salter (1944).
AFRIKAANSE OPSOMMING: Die filogenetiese verwantskappe en taksonomiese klassifikasie van Suid Afrikaanse Oxalis L. spesies is nog baie onduidelik, beide binne die gebied en ten opsigte van die presiese plasing binne die genus as 'n geheel. Vorige werk, uitsluitlik gebaseer op morfologiese en palinologiese kenmerke, was tot dusver nog net gedeeltelik suksesvol in die identifikasie van natuurlike groepe binne die inheemse taksa van die gebied. Onlangse studies op 'n paar inheemse spesies het die nut van die plastied trnL-trnF nie-koderende DNA area bevestig vir die rekonstruksie van filogenetiese verwantskappe in die genus. Hierdie studie is gerig op die taksonomiese monofilie en verwantskappe van die onnatuurlike seksie Angustatae subseksie Lineares, deur gebruik te maak van DNA basis-volgorde data. Die filogenetiese rekonstruksie van Suid Afrikaanse Oxalis spesies dui aan dat vyf van die subseksies van seksie Angustatae sensu Salter (1944) polifileties is, met sterk steun daarvoor dat drie van hulle onnatuurlik is. Die lede van subseksie Lineares is tussen drie verskillende groepe versprei; twee van dié groepe het sterk ondersteuning. Nie een van die drie groepe bestaan uitsluitlik uit spesies van subseksie Lineares nie. So ook is vier van die sewe groepe van verwante spesies binne subseksie Lineares sensu Salter (1944) polifileties. Stuifmeel data volgens Dreyer (1996) ondersteun die groepe wat deur die DNA volgordes uitgewys is, terwyl baie min morfologiese kenmerke gebruik kan word as potensiële sinapomorfe/kenmerke. Die filogenetiese rekonstruksie ondersteun dus die palinologiese data van die subseksie, en dui op die dringende behoefte aan 'n hersiening van die huidige morfologiese klassifikasie van Salter (1944).
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Svoboda, Harlan T. "A Systematic Revision of Passiflora Section Dysosmia (Passifloraceae)." Ohio University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1532018615453033.
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Hartenstein, Volker, Albert Cardona, Stephan Saalfeld, Stephan Preibisch, Benjamin Schmid, Anchi Cheng, Jim Pulokas, and Pavel Tomancak. "An Integrated Micro- and Macroarchitectural Analysis of the Drosophila Brain by Computer-Assisted Serial Section Electron Microscopy." Public Library of Science, 2010. https://tud.qucosa.de/id/qucosa%3A27886.
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The analysis of microcircuitry (the connectivity at the level of individual neuronal processes and synapses), which is indispensable for our understanding of brain function, is based on serial transmission electron microscopy (TEM) or one of its modern variants. Due to technical limitations, most previous studies that used serial TEM recorded relatively small stacks of individual neurons. As a result, our knowledge of microcircuitry in any nervous system is very limited. We applied the software package TrakEM2 to reconstruct neuronal microcircuitry from TEM sections of a small brain, the early larval brain of Drosophila melanogaster. TrakEM2 enables us to embed the analysis of the TEM image volumes at the microcircuit level into a light microscopically derived neuro-anatomical framework, by registering confocal stacks containing sparsely labeled neural structures with the TEM image volume. We imaged two sets of serial TEM sections of the Drosophila first instar larval brain neuropile and one ventral nerve cord segment, and here report our first results pertaining to Drosophila brain microcircuitry. Terminal neurites fall into a small number of generic classes termed globular, varicose, axiform, and dendritiform. Globular and varicose neurites have large diameter segments that carry almost exclusively presynaptic sites. Dendritiform neurites are thin, highly branched processes that are almost exclusively postsynaptic. Due to the high branching density of dendritiform fibers and the fact that synapses are polyadic, neurites are highly interconnected even within small neuropile volumes. We describe the network motifs most frequently encountered in the Drosophila neuropile. Our study introduces an approach towards a comprehensive anatomical reconstruction of neuronal microcircuitry and delivers microcircuitry comparisons between vertebrate and insect neuropile.
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Horak, Tracey Anne. "An analysis of the caesarean section rate at Mowbray Maternity Hospital using Robson's Ten group Classification System by Tracey Anne Horak." Master's thesis, University of Cape Town, 2012. http://hdl.handle.net/11427/3046.
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Konstantelos, Dimitrios, Sascha Ifflaender, Jürgen Dinger, Wolfram Burkhardt, and Mario Rüdiger. "Analyzing support of postnatal transition in term infants after c-section." BioMed Central, 2014. https://tud.qucosa.de/id/qucosa%3A28700.
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Background: Whereas good data are available on the resuscitation of infants, little is known regarding support of
postnatal transition in low-risk term infants after c-section. The present study was performed to describe current
delivery room (DR) management of term infants born by c-section in our institution by analyzing videos that were
recorded within a quality assurance program.
Methods: DR- management is routinely recorded within a quality assurance program. Cross-sectional study of
videos of term infants born by c-section. Videos were analyzed with respect to time point, duration and number of
all medical interventions. Study period was between January and December 2012.
Results: 186 videos were analyzed. The majority of infants (73%) were without support of postnatal transition. In
infants with support of transition, majority of infants received respiratory support, starting in median after
3.4 minutes (range 0.4-14.2) and lasting for 8.8 (1.5-28.5) minutes. Only 33% of infants with support had to be
admitted to the NICU, the remaining infants were returned to the mother after a median of 13.5 (8-42) minutes. A
great inter- and intra-individual variation with respect to the sequence of interventions was found.
Conclusions: The study provides data for an internal quality improvement program and supports the benefit of
using routine video recording of DR-management. Furthermore, data can be used for benchmarking with current
practice in other centers.
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Milton, Joseph J. "Phylogenetic analyses and taxonomic studies of Senecioninae : southern African Senecio section Senecio." Thesis, St Andrews, 2009. http://hdl.handle.net/10023/701.
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Roonprasang, Kiattisak. "Thermal Analysis of Multi-Cylinder Drying Section with variant Geometry." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2008. http://nbn-resolving.de/urn:nbn:de:bsz:14-ds-1228929176333-20817.
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This specific-purpose mathematical model was developed for the drying process in a multi-cylinder drying section. The unsteady state of one-dimensional heat conduction equation has been applied to mathematical model of both, cylinder shell and paper web. The internal mass transfer of the paper web has not been included in this work. The calculations of the simulation program use an implicit numerical method. The drying path length along the machine direction has been divided into 4 drying phases for each drying cylinder. Each drying phase has been divided in small sub-elements. In each sub-element, the heat and mass transfer across boundary conditions have been solved simultaneously in the simulation program, which runs with MatLAB®.
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Kuhn, S., M. Buchholz, T. Wels, K. Breunig, B. Scholten, I. Spahn, and H. H. Coenen. "Cross section measurements on 61Cu for proton beam monitoring above 20 MeV." Helmholtz-Zentrum Dresden - Rossendorf, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:d120-qucosa-166097.
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Introduction
All experimental studies involving charged particle induced nuclear reactions require a precise knowledge of monitor reactions. A number of well described proton induced monitor reactions exist in the lower energy range [1], which is covered by most medical cyclotrons. Concerning proton energies above 20 MeV, however, the accuracy of the monitor reactions declines as cross section data becomes scarcer. Furthermore, the growing interest in precise determination of projectile energies by comparing of ratios of monitor reaction cross sections demands new measurements and evaluations of known data for high threshold monitor radionuclides.
In this work cross section measurements on the formation of 61Cu were done and energy de-pendent radionuclide ratios were calculated.
Material and Methods
For investigation of the natCu(p,x)61Cu reaction copper foils of natural isotopic composition (Goodfellow Ltd.) were irradiated. The targets were of 10 and 20 μm thickness, having a diameter of 15 mm.
Proton bombardments up to 45 MeV incident energy were done in the stacked-foil arrangement at the accelerator JULIC of the Nuclear Physics Institute (IKP) of the Forschungszentrum Jülich. In addition to an internal irradiation possibility the cyclotron is equipped with an external target station which was used for most experiments. It can adapt standard and slanting solid target holders and is equipped with a water cooled four sector collimator and additional helium cooling of the entry foil.
Several irradiations were executed. In each stack, besides copper samples, aluminium absorbers and additional nickel monitor foils were also placed, the latter for the determination of the respective beam current.
The produced radioactivity of 61Cu was analysed non-destructively using HPGe γ-ray detectors (EG&G Ortec).
Results and Conclusion
Reaction cross sections of the natCu(p,x)61Cu process up to 45 MeV were measured and com-pared with existing data from the literature (FIG. 2). Except for the data of Williams et al. our results are in good agreement, showing a maxi-mum of about 165 mbarn at 37.5 MeV proton energy. The overall uncertainty of the new cross section data is between 8 and 10 %.
In FIG. 3, the excitation functions of the relevant monitor reactions on Cu are shown.
In combination with the excitation function of the natCu(p,xn)62Zn reaction, isotope ratios were calculated which can be used for determination of the proton energy within a target stack in the energy range of 22–40 MeV as described by Piel et al. [3]. FIGURE 4 shows the cross section ratio in dependence of the proton energy.
Above this energy, 65Zn could be used to generate isotope ratios for energy determination, although the long half-life (T½ = 244.3 d) of that radionuclide may be a problem.
Additional cross section measurements are planned in order to further strengthen the data base of this potential monitor reaction. The results of this work shall be evaluated in the framework of an ongoing Coordinated Research Project of the IAEA.
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Seidlitz, Holger, Lars Ulke-Winter, Colin Gerstenberger, and Lothar Kroll. "Dimensioning of Punctiform Metal-Composite Joints: A Section-Force Related Failure Criterion." Universitätsbibliothek Chemnitz, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-152889.
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Reliable line production processes and simulation tools play a central role for the structural integration of thermoplastic composites in advanced lightweight constructions. Provided that material- adapted joining technologies are available, they can be applied in heavy-duty multi-material designs (MMD). A load-adapted approach was implemented into the new fully automatic and faulttolerant thermo mechanical flow drill joining (FDJ) concept. With this method it is possible to manufacture reproducible high strength FRP/metal-joints within short cycle times and without use of extra joining elements for the first time. The analysis of FDJ joints requires a simplified model of the joint to enable efficient numerical simulations. The present work introduces a strategy in modeling a finite-element based analogous-approach for FDJ-joints with glass fiber reinforced polypropylene and high-strength steel. Combined with a newly developed section-force related failure criterion, it is possible to predict the fundamental failure behavior in multi-axial stress states. The functionality of the holistic approach is illustrated by a demonstrator that represents a part of a car body-in-white structure. The comparison of simulated and experimentally determined failure loads proves the applicability for several combined load cases.
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Oualidi, Jalal El. "Biosystématique et taxinomie des "Teucrium" de la section "Polium (Lamiaceae)" dans le bassin méditerranéen occidental : différents aspects de la variation au Maroc, en France et en Espagne." Montpellier 2, 1991. http://www.theses.fr/1991MON20190.
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Dans le bassin mediterraneen occidental, les teucrium sect. Polium constituent un groupe d'especes tres peu differenciees dont beaucoup de taxons, notamment de la sous-sect. Polium, sont encore en cours de speciation. Les especes offrent, de ce fait, tres peu de caracteres diagnostiques fixes. Dans ce travail, nous avons etudie la variation morphologique, chimique, cytologique et biographique au sein de certains groupes d'especes tres affines. 1) la forme du calice, marqueur morphologique commun a certains de la sous-sect. Polium, a ete testee a l'echelle de la population, de l'espece et d'un groupe d'especes du bassin mediterraneen occidental. 2) le complexe t. Puechiae greut. Et bur. -t. Mairei sen. -t. Polium l. A ete etudie, a la fois a l'echelle intrapopulationnelle, interpopulationnelle et interspecifique. Certains taxons nord-africains et francais se detachent du groupe iberique par des parametres de croissance et certains marqueurs chimiques et morphologiques. 3) teucrium mideltense (batt. ) maire, espece endemique du haut atlas marocain, montre un paradose taxinomique: il se range dans la sous sect. Polium par son appareil reproducteur et s'en ecarte par son appareil vegetatif. Sa position taxonomique au sein de la section et le choix des caracteres d'une clef de la section sont discutes. 4) un exemple de variation geographique et de speciation recente, selon le concept allopatrique, est analyse et discute dans le complexe t. Huotii emb. Et maire, endemique du massif rifain (maroc)
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Jenkins, Matthew Lee. "Wetland Delineation and Section 404/401 Permitting: An Internship with Carolina Wetland Services." Oxford, Ohio : Miami University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=miami1150754893.
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Kormoll, Kathrin. "Mass reconstruction techniques and cross section measurement for Z→ττ→eμ+4υ with the ATLAS experiment." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2013. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-110173.
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Die Suche nach dem Higgs Boson ist ein zentraler Forschungsschwerpunkt der modernen Teilchenphysik. Zum einen ist das Higgs Boson das einzige bislang unentdeckte Teilchen des Standard Modells. Zum anderen gibt seine mögliche Entdeckung eine bessere Einsicht in die Natur neuer Physik. Mit der Inbetriebnahme des Large Hadron Colliders, LHC, am europäischen Kernforschungszentrum CERN bei Genf konnten Proton-Proton Kollisionen mit bislang unerreichten Schwerpunktsenergien von √s = 7 TeV beziehungsweise √s = 8 TeV erzielt werden.
In der vorliegenden Arbeit wird die Messung des Wechselwirkungsquerschnitts pp→Z/γ→τ⁺τ⁻ im gemischten leptonischen Endzustand mit Daten des ATLAS Detektors durchgeführt. Der Zerfall der kohärenten Summe aus Photon, γ, und Z Boson in zwei τ -Leptonen ist ein irreduzibler Untergrund von Higgs Boson Zerfällen in zwei τ -Leptonen. Eine genaue Kenntniss des Massenspektrums sowie dessen Normierung ist deswegen für die Higgs Boson Suche essentiell. Die verwendeten Daten entsprechen einer integrierten Luminosität von L = 35,51 pb⁻¹ bei einer Schwerpunktsenergie von √s = 7 TeV. Die Messung erzielt einen Wechselwirkungsquerschnitt von σ×BR(Z→ττ ) = (1041 ± 143 ± 74 ± 35) pb. Die angegebenen Unsicherheiten entsprechen den statistischen, den systematischen und den Unsicherheiten aus Luminositätsmessungen. Das Ergebnis stimmt mit dem theoretisch bestimmten Wert sowie dem Ergebnis anderer Experimente innerhalb seiner Unsicherheiten überein.
Im zweiten Teil der Arbeit werden verschiedene Massenrekonstruktionsmethoden von Zerfällen in zwei τ-Leptonen untersucht. Die Analyse konzentriert sich dabei auf Higgs Bosonen, der minimalen supersymmetrischen Erweiterung des Standard Modells; insbesondere auf deren Zerfall in zwei τ-Leptonen und weiter in den gemischten leptonischen Endzustand, Φ→τ⁺τ⁻→eμ+4υ. Die untersuchten Massenrekonstruktionsmethoden sind die sichtbare Masse, die effektive Masse, sowie die früh- und spät-projizierte transversale Masse. Weiterhin werden Abhängigkeiten der Massenverteilungen vom transversalen Impuls der Leptonen des Endzustandes, sowie der fehlenden transversalen Energie festgestellt. Eine Abhängigkeit vom transversalen Impuls des energiereichsten Jets hingegen konnte nicht nachgewiesen werden. Eine mögliche Eliminierung der Variablenabhängigkeiten wird untersucht, zeigt jedoch dass sie zu einer schlechteren Trennung zwischen Signal und Untergrundprozessen sowie einer schlechteren Auflösung unterschiedlicher Higgs Boson Massen führt. Mit der Kalibrierung der berechneten Massen der verschiedenen Rekonstruktionstechniken wird die Arbeit abgeschlossen.
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Al-Dafafea, Taher. "Analyses expérimentale et numérique du comportement de poutres à ouvertures d'âmes raidies." Thesis, Université Clermont Auvergne (2017-2020), 2018. http://www.theses.fr/2018CLFAC024/document.
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La présente thèse vise à caractériser le comportement mécanique à la ruine de poutres métalliques avec ouvertures, de formes et de tailles variables, renforcées ou non par raidisseurs. L’étude s’intéresse à des poutres de dimensions réalistes et s’appuie sur une combinaison de différentes approches : essais, modèles éléments finis et modèles analytiques. Les raidisseurs sont généralement utilisés pour corriger certaines faiblesses au niveau du comportement mécanique autour des ouvertures. Autour des ouvertures rectangulaires, ces raidisseurs, disposés verticalement ou horizontalement, ont fait l’objet de peu d’études scientifiques publiées. Généralement, le comportement des poutres à ouvertures d’âmes est considéré comme étant similaire à celui d’une poutre échelle (ou poutre Vierendeel) chargée aux noeuds. Cette hypothèse permet de considérer que les membrures de l’ouverture sont soumises à un moment fléchissant local bi-triangulaire sur la longueur de l’ouverture. Cependant, la distribution du moment fléchissant, et de ses contraintes axiales, le long d’une membrure peut s’avérer être plus complexe et dépend de la forme de l’ouverture (rectangulaire, hexagonale, circulaire, sinusoïdale ou quelconque), de la position de l’ouverture le long de la poutre et enfin, du type de chargement (concentré ou uniformément réparti). Plusieurs études numériques et expérimentales ont déjà été menées sur les poutres à ouvertures d’âmes et ont permis de développer différentes approches analytiques en vue de décrire leurs comportements. Cependant, ces modèles montrent certaines imprécisions ou insuffisances pour différents types et dimensions d’ouvertures notamment les ouvertures rectangulaires. Les travaux présentés dans cette thèse font le point sur les principaux modèles existants de calcul de résistance des poutres avec ouvertures d’âmes. Ils présentent notamment leurs avantages et limites. Pour conforter les descriptions basées sur les analyses bibliographiques, une campagne expérimentale est réalisée pour valider un modèle éléments finis développé dans le cadre de l’étude. Les essais s’appuient sur des tronçons de poutres de dimensions réalistes avec différentes configurations d’ouvertures isolées renforcées ou non par des raidisseurs. Les mesures autour de l’ouverture utilisent des jauges de déformation pour analyser le profil des contraintes et son évolution, au cours du chargement, dans différentes sections critiques. Les essais sont menés jusqu’à la ruine qui s’est développée généralement par une combinaison de comportement élasto-plastique et d’instabilité locale autour des ouvertures. Certaines ruines se sont produites par rupture en traction-cisaillement de l’acier dans des zones critiques. Les analyses numériques et expérimentales ont permis d’étudier l’influence de différentes conditions sur la distribution des contraintes, notamment axiales, au sein d’une membrure d’ouverture, en vue d’évaluer son potentiel de voilement local qui reste un phénomène complexe à appréhender. Elles ont permis aussi de comprendre le fonctionnement mécanique des ouvertures renforcées par des raidisseurs de différentes dimensions et positions. L’étude paramétrique menée, en utilisant le modèle éléments finis validé par essai, a permis d’évaluer la pertinence des hypothèses retenues dans les approches analytiques existantes. Ces analyses ont permis aussi de proposer un modèle analytique tenant compte du comportement d’ouvertures isolées avec ou sans raidisseursThe present thesis aims to characterize the mechanical behavior to failure of steel beams with openings, with variable shapes and sizes, reinforced or not by stiffeners. The study considers beams of realistic dimensions and combines different approaches: tests, finite element models and analytical models. The stiffeners are generally used to improve some weaknesses in the mechanical behavior around the openings. Around rectangular openings, these stiffeners, in vertical or horizontal arrangements, have been the subject of limited number of scientific publications. In general, the behavior of beams with web openings is considered similar to that of Vierendeel beams with loads applied at the nodes. This hypothesis allows to consider that each frame around the opening is characterized by a bi-triangular local bending moment along the frame elements. In fact, the bending moment distribution, and their resultant axial stresses, along a frame can be more complex and depends on the shape of the opening (rectangular, hexagonal, circular, sinusoidal or any), the position of the opening along the beam and finally, the type of loading (concentrated or uniformly distributed). Several numerical and experimental studies have been conducted on the beams with web openings and different analytical approaches have been developed to describe and predict the behavior of these beams. However, these models show some inaccuracies or inadequacies depending on the types and dimensions of openings including rectangular openings. The work presented in this thesis examines the main existing models predicting the resistance for beams with web openings. It shows their advantages and limits based on the existing but limited results. To obtain additional and specific results to be used in the comparisons and to validate a finite element model developed within the framework of the study, an experimental campaign is carried out. The tests are focused on beams of real dimensions with different configurations of isolated openings reinforced or not by stiffeners. The measurements around the opening use strain gauges to analyze the stress profile and its evolution, during loading, in different critical sections. The tests are carried out until failure generally characterized by a combination of elastic-plastic behavior and local instability around openings. Some final failures occurred by tensile-shear fracture of steel in some critical zones. Numerical and experimental analyzes are performed to study the influence of various conditions on the stresses distributions, in particular axial stresses, within the frames around the openings. The stress distribution is mainly observed to evaluate the local buckling potential that remains a complex phenomenon difficult to predict. The results are also analyzed to understand the mechanical behavior of the openings reinforced by stiffeners of different dimensions and positions. The parametric study conducted using the validated finite element model allows evaluating the relevance of the assumptions considered in the existing analytical approaches. These analyzes made it possible to propose an analytical model taking into-account the behavior of isolated openings with or without stiffeners
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Ferreira, Elton Carlos 1982. "Utilização do Sistema de Classificação de Dez Grupos de Robson para partos na investigação da morbidade materna grave = Applying the Robson Ten Group Classification System for deliveries to the investigation of severe maternal morbidity." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/312757.
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Orientadores: Jose Guilherme Cecatti, Maria Laura Costa do NascimentoDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas
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Resumo: Objetivo: avaliar a distribuição dos partos segundo o Sistema de Classificação em Dez Grupos de Robson (RTGCS) explorando os dados da Rede Brasileira de Vigilância da Morbidade Materna Grave (RBVMMG) e do Hospital da Mulher (CAISM) da Universidade Estadual de Campinas (UNICAMP), Brasil; e comparação de ambos com os dados do estudo Global Survey da Organização Mundial de Saúde (WHO). Método: Foram realizadas duas abordagens. A primeira foi uma análise secundária de um estudo de corte transversal multicêntrico que ocorreu em 27 maternidades brasileiras de referência, localizadas nas cinco regiões do país e participantes da RBVMMG. Foi realizada a codificação dos dados para alocação de todas as mulheres segundo o RTGCS e as mulheres foram classificadas de acordo com o espectro clínico de gravidade e a condição subjacente de morbidade materna grave. Para a segunda abordagem, foi realizado um estudo de corte transversal, com avaliação das mulheres admitidas para parto no CAISM no período de janeiro 2009 a julho de 2013. As mulheres foram agrupadas segundo a RTGCS e, adicionalmente, a distribuição das mulheres entre os diferentes grupos foi comparada entre os casos que tiveram morbidade materna grave, operacionalmente definida pela necessidade de internação em unidade de terapia intensiva (UTI), com os demais casos sem complicações graves. Para as duas abordagens (RBVMMG e CAISM), realizou-se também uma comparação com resultados publicados de outro grande estudo, realizado em diferentes contextos e países, fundamentalmente com os dados para o Brasil, disponíveis no estudo Global Survey da WHO. Resultados: Para a RBVMMG, das 7247 mulheres que compuseram o estudo, 73.2% foram submetidas à cesariana (CS). O grupo 10, grupo com provável indicação de cesárea por complicação materna e/ou fetal, foi o mais prevalente com 33.9% e também aquele com maior contribuição para a taxa geral de cesárea, 28%. Os grupos que tiveram maior gravidade (¨near miss¨ e óbito materno) foram, em ordem decrescente, os grupos 7 e 9, o grupo 8 e o grupo 10. O grupo 3 teve um caso de resultado materno grave (¨near miss¨ + óbito materno) para cada 29 casos de condição potencialmente ameaçadora da vida. Nas mulheres desse grupo submetidas a CS, essa relação atingiu valores de 1:10. Em todos os grupos avaliados, a hipertensão foi o fator de gravidade mais frequente. Na segunda abordagem, foram admitidas 12.771 parturientes durante o período do estudo. A taxa de cesariana encontrada foi de 46.6%. O grupo 1 foi o mais prevalente com 28.1%, sendo o grupo 5 aquele que mais contribui para a taxa geral de cesárea (12.7%). Apresentaram, proporcionalmente, mais internação em UTI os grupos 10 (46.8%), 5 (13.3%) e 2 com 9.8%. Conclusões: O estudo evidenciou uma alta taxa de cesárea nas duas populações avaliadas e o uso do RTGCS mostrou-se útil, evidenciando grupos clinicamente relevantes com alta taxa de parto por cesárea. Estudos futuros serão necessários para melhor avaliar a associação entre cesárea e morbidade materna grave, assim como definir possíveis intervenções e a taxa de cesárea esperada para esse grupo específico de mulheres
Abstract: Objective: To evaluate the distribution of delivering women according to the Robson¿s Ten Group Classification System (RTGCS) exploring the data from the Brazilian Network for the Surveillance of Severe Maternal Morbidity (RBVMMG) and from a tertiary hospital (CAISM), University of Campinas, Brazil; comparing both data with that from the WHO Global survey. Method: Two approaches were proposed. The first, a secondary analysis of a database obtained from a multicenter cross-sectional study taking place in 27 referral obstetric units located in the five geographical regions of Brazil, members of the Brazilian Network for the Surveillance of Severe Maternal Morbidity (RBVMMG), was carried out. For this analysis, data was organized following information necessary to classify all women into one of the RTGCS and cases from each of the 10 groups were classified according to case severity and underlying cause of severe morbidity. Subsequently, certain Robson groups were subdivided for further analysis. For the second approach, a cross-sectional study of data from women delivering at CAISM from January 2009 to July 2013 was carried out. Women were grouped according to RTGCS and, additionally, the distribution of women among the different groups was compared between cases who had severe maternal morbidity (SMM), operationally defined by intensive care unit (ICU) admission, with the other cases without severe complications. For both approaches (RBVMMG and CAISM), patients distributed among groups were compared to another Brazilian study population, available on the WHO Global Survey study. Results: For RBVMMG, among the 7247 women considered, 73.2% underwent cesarean section (CS). Group 10 had the highest prevalence rate (33.9%), also contributing most significantly (28%) to the overall CS rate. Groups associated with a severe maternal outcome (maternal ¨near miss¨ or maternal death), in decreasing order were: groups 7 and 9, 8 and 10. Group 3 had one case of severe maternal outcome (maternal ¨near miss¨ + maternal death) for every 29 cases of potentially life-threatening conditions. When evaluating only women undergoing CS in this group, ratios of 1:10 were achieved, indicating a worse outcome. Among all groups evaluated, hypertension was the most common condition of severity. For CAISM, of the 12771 women, 46.6% underwent CS. Group 1 had the highest prevalence rate (28%) and Group 5 contributed most significantly to overall CS rates. ICU admission was proportionally higher in groups 10 (46.8%), 5 (13.3%) and 2 with 9.8%.Conclusions: The study demonstrated a high cesarean section rate in the two populations studied and the use of RTGCS proved to be extremely useful, showing clinically relevant groups with high rates of cesarean section. Future studies are needed to better evaluate the association between cesarean section and severe maternal morbidity, as well as to define possible interventions and the expected cesarean section rate for this particular group of women
Mestrado
Saúde Materna e Perinatal
Mestre em Ciências da Saúde
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Mgaya, Andrew Hans. "Improving the quality of caesarean section in a low-resource setting : An intervention by criteria-based audit at a tertiary hospital, Dar es Salaam, Tanzania." Doctoral thesis, Uppsala universitet, Internationell mödra- och barnhälsovård (IMCH), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-319192.
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A sharp increase in caesarean section (CS) rates at the Muhimbili National Referral Hospital (MNH) – a tertiary referral hospital in Tanzania – by 50% in 2000–2011, was associated with concomitant increase in maternal complications and deaths and inconsistent improvement in newborn outcomes. The aims of this thesis were to explore care providers’ in-depth perspective of the reasons for these high rates of CS, and to evaluate and improve standards of care for the most common indica-tions of CS, obstructed labour and fetal distress, which are also major causes of adverse maternal and neonatal outcomes. This thesis reports an investigation performed at MNH, Tanzania. For Paper I, qualitative methods were employed and demonstrated how care providers dismissed their responsibility for the rising CS rate; and, instead, projected the causes onto factors beyond their control. Additionally, dysfunctinal teamwork, transparency, and previous poorly conducted clinical audits led to fear of blame among care providers in cases of poor outcome that subsequently encougared defensive practise by assigning unnecessary CS. Papers II and III evaluated stand-ards of care using a criteria-based audit (CBA) of obstructed labour and fetal dis-tress. After implementing audit-feedback recommendations, the standards of diag-nosis of fetal distress improved by 16% and obstructed labour by 7%. Similarly, the standards of management preceding CS improved tenfold for fetal distress and doubled for obstructed labour. The impact of the CBA process was evaluated by comparing the maternal and perinatal outcomes categorized into Robson groups (Paper IV) of all deliveries occurring before and after the audit process (n=27,960). After the CBA process, there was a 50% risk reduction of severe perinatal morbidi-ty/mortality for patients with obstructed labour. The overall CS rates increased by 10%, and this was attributed to an increase in the CS rate among breech, term preg-nancies (Robson group 6), and preterm pregnancies (Robson group 10) that specifi-cally had reduced risk of poor perinatal outcome. The overall neonatal distress rates were also reduced by 20%, and this was attributed to a decrease in the neonatal distress rate among low-risk, term pregnancies (Robson group 3). Importantly, the increased rates of poor perinatal outcomes were associated with referred patients that had higher risk of neonatal distress and PMR than non–referred patients, after CBA process. In conclusion, the studies managed to educate the care providers to take on their roles as decision-makers and medical experts to minimize unnecessary CS, using the available resources. Care providers’ commitment to achieve the best practice should be sustained and effort for stepwise upgrading quality of obstetric care should be supported by the hospital management from the primary to tertiary referral level.
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Böhmer, Heiner. "Barbara Wehr / Frédéric Nicolosi (edd.), Pragmatique historique et syntaxe. Actes de la section du même nom du XXXIe Romanistentag allemand (Bonn, 27. 9. – 1. 10. 2009)." De Gruyter, 2013. https://tud.qucosa.de/id/qucosa%3A71158.
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In dem seit Herbst 2012 vorliegenden Band, der von der Mainzer Italianistin und Franko-Romanistin Barbara Wehr und einem Mitarbeiter (Frédéric Nicolosi) herausgegeben wurde, sind 14 Beiträge versammelt, die zwei hauptsächliche Forschungsinteressen bedienen: Einerseits wird in allen Aufsätzen ganz allgemein erprobt, wie sich die pragmatisch orientierte und die strukturell bestimmte historische Syntaxanalyse gegenseitig befruchten können, um genaue Beschreibungen formaler Eigenschaften mit differenzierten funktionalen Erörterungen zu verbinden; andererseits liegt das Gros der Artikel des Bandes in der Linie der Erforschung eines ganz bestimmten Teilthemas, nämlich von Strukturen, die in den älteren Sprachstufen des Romanischen Topic und Fokus markierten, vor allem Spaltsätze und Verlagerungen von Wortgruppen mit oder ohne pronominale Spur.
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Tillich, Daniel. "Generalized Modeling and Estimation of Rating Classes and Default Probabilities Considering Dependencies in Cross and Longitudinal Section." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-222601.
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Our sample (Xit; Yit) consists of pairs of variables. The real variable Xit measures the creditworthiness of individual i in period t. The Bernoulli variable Yit is the default indicator of individual i in period t. The objective is to estimate a credit rating system, i.e. to particularly divide the range of the creditworthiness into several rating classes, each with a homogeneous default risk. The field of change point analysis provides a way to estimate the breakpoints between the rating classes. As yet, the literature only considers models without dependencies or with dependence only in cross section. This contribution proposes multi-period models including dependencies in cross section as well as in longitudinal section. Furthermore, estimators for the model parameters are suggested. The estimators are applied to a data set of a German credit bureau.
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Pönitz, Erik. "Messung von Wirkungsquerschnitten für die Streuung von Neutronen im Energiebereich von 2 MeV bis 4 MeV mit der 15N(p,n)-Reaktion als Neutronenquelle." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-39906.
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In zukünftigen kerntechnischen Anlagen können die Materialien Blei und Bismut eine größere Rolle spielen als heute. Für die Planung dieser Anlagen werden verlässliche Wirkungsquerschnittsdaten benötigt. Insbesondere der Neutronentransport in einem Blei-Spallationstarget eines beschleunigergetriebenen unterkritischen Reaktors hängt stark von den inelastischen Streuquerschnitten im Energiebereich von 0,5 MeV bis 6 MeV ab. In den vergangenen 20 Jahren wurden elastische und inelastische Neutronenstreuquerschnitte mit hoher Präzision für eine Vielzahl von Elementen am PTB-Flugzeitspektrometer gemessen. Zur Erzeugung der Neutronen wurde hauptsächlich die D(d,n)-Reaktion genutzt. Aufgrund des Q-Wertes der Reaktion und der verfügbaren Deuteronenenergien können Neutronen im Energiebereich von 6 MeV bis 16 MeV erzeugt werden. Die Messung von Wirkungsquerschnitten bei niedrigeren Energien erfordert somit die Verwendung einer anderen neutronenerzeugenden Reaktion. Hierfür wurde die 15N(p,n)15O-Reaktion ausgewählt, da sie die Erzeugung monoenergetischer Neutronen bis zu einer Energie von 5,7 MeV erlaubt. In dieser Arbeit wird die 15N(p,n)-Reaktion auf ihre Eignung als Quelle monoenergetischer Neutronen in Streuexperimenten untersucht. Die Untersuchung der Reaktion beinhaltet die Messung von differentiellen Wirkungsquerschnitten für ausgewählte Energien und die Auswahl von optimalen Targetbedingungen. Differentielle elastische und inelastische Neutronenstreuquerschnitte wurden unter Anwendung der Flugzeitmethode für Blei bei vier Energien zwischen 2 MeV und 4 MeV gemessen. Eine Bleiprobe mit natürlicher Isotopenzusammensetzung wurde verwendet. Für den Nachweis der gestreuten Neutronen wurden NE213 Flüssigszintillatoren verwendet, deren Nachweiswahrscheinlichkeit gut bekannt ist. Winkelintegrierte Wirkungsquerschnitte wurden mit einem Legendre-Polynomfit unter Verwendung der Methode der kleinsten Quadrate bestimmt. Zusätzlich erfolgten Messungen für die isotopenreinen Streuproben 209Bi und 181Ta bei 4 MeV Neutronenenergie. Die Ergebnisse werden mit denen früherer Experimente und aktuellen Evaluationen verglichenIn future nuclear facilities, the materials lead and bismuth can play a more important role than in today’s nuclear reactors. Reliable cross section data are required for the design of those facilities. In particular the neutron transport in the lead spallation target of an Accelerator-Driven Subcritical Reactor strongly depends on the inelastic neutron scattering cross sections in the energy region from 0.5MeV to 6 MeV. In the recent 20 years, elastic and inelastic neutron scattering cross sections were measured with high precision for a variety of elements at the PTB time-of-flight spectrometer. The D(d,n) reaction was primarily used for the production of neutrons. Because of the Q value of the reaction and the available deuteron energies, neutrons in the energy range from 6MeV to 16MeV can be produced. For the cross section measurement at lower energies, however, another neutron producing reaction is required. The 15N(p,n)15O reaction was chosen, as it allows the production of monoenergetic neutrons with up to 5.7MeV energy. In this work, the 15N(p,n) reaction was studied with focus on the suitability as a source for monoenergetic neutrons in scattering experiments. This includes the measurement of differential cross sections for the neutron producing reaction and the choice of optimum target conditions. Differential elastic and inelastic neutron scattering cross sections were measured for lead at four energies in the region from 2MeV to 4MeV incident neutron energy using the time-offlight technique. A lead sample with natural isotopic composition was used. NE213 liquid scintillation detectors with well-known detection efficiencies were used for the detection of the scattered neutrons. Angle-integrated cross sections were determined by a Legendre polynomial expansion using least-squares methods. Additionally, measurements were carried out for isotopically pure 209Bi and 181Ta samples at 4MeV incident neutron energy. Results are compared with other measurements and recent evaluations
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Pässler, Roland. "Alternative Way for Detecting Franck-Condon Shifts from Thermally Broadened Photoneutralization Cross-Section Bands of Deep Traps in Semiconductors." Universitätsbibliothek Chemnitz, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-201000270.
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Gude, Maik, Florian Lenz, Andreas Gruhl, Bernhard Witschel, Andreas Ulbricht, and Werner Hufenbach. "Design and automated manufacturing of profiled composite driveshafts." De Gruyter, 2015. https://tud.qucosa.de/id/qucosa%3A38566.
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The high specific strength and stiffness characteristics of composite materials such as carbon fiber-reinforced plastic (CFRP) allow a significant weight reduction of the structural machine components such as automobile driveshafts. But high material cost and rather low productivity of the established manufacturing processes (e.g., filament winding) often inhibit the use of CFRP components in a high-volume car series. In this paper, a novel composite driveshaft system based on a profiled CFRP tube is presented. This system is designed to be produced by a continuous pultrusion process to achieve a significant reduction of the manufacturing costs. A cost assessment study was conducted to quantify the benefit of the developed continuous manufacturing process. In comparison with the state-of-the-art filament winding process, a cost reduction of 36% for the composite shaft body can be obtained. Moreover, the proposed fiber layup processes – braiding and continuous winding – offer the potential to manipulate the reinforcement architecture to maximize material utilization without reducing the manufacturing efficiency. This potential is investigated and validated by experimental tests. A difference in the load bearing capacity of more than 100% between different reinforcing architectures is shown.
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Mouroutis, Theodoros. "Segmentation and classification of cell nuclei in tissue sections." Thesis, Imperial College London, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.343898.
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Zyweck, Anthony. "Preprocessing issues in high resolution radar target classification." Title page, contents and abstract only, 1995. http://web4.library.adelaide.edu.au/theses/09PH/09phz995.pdf.
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Bibliography: leaves 287-294. This thesis addresses preprocessing issues for radar target classification from high resolution radar imagery. High resolution radar imagery of real aircraft in flight and of a MIRAGE aircraft on a turntable is examined. An algorithm to coherently average high resolution range profile is proposed.
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Zocher, Maria Teresa, Jos J. Rozema, Nicole Oertel, Jens Dawczynski, Peter Wiedemann, and Franziska G. Rauscher. "Biometry and visual function of a healthy cohort in Leipzig, Germany." Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-205179.
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Background: Cross-sectional survey of ocular biometry and visual function in healthy eyes across the life span of a German population aged 20 to 69 years (n = 218). Subject number in percent per age category reflected the percentage within the respective age band of the population of Leipzig, Germany. Methods: Measurements obtained: subjective and objective refraction, best-corrected visual acuity, accommodation, contrast sensitivity, topography and pachymetry with Scheimpflug camera, axial length with non-contact partial coherence interferometry, and spectral-domain optical coherence tomography of the retina. Pearson correlation coefficients with corresponding p-values were given to present interrelationships between stature, biometric and
refractive parameters or their associations with age. Two-sample T-tests were used to calculate gender differences. The area under the logarithmic contrast sensitivity function (AULCSF) was calculated for the analysis of contrast sensitivity as a single figure across a range of spatial frequencies. Results: The results of axial length (AL), anterior chamber depth (ACD) and anterior chamber volume (ACV) differed as a function of the age of the participants (rho (p value): AL −0.19 (0.006), ACD −0.56 (< 0.001), ACV-0.52 (< 0.001)). Longer eyes had deeper ACD (AL:ACD 0.62 (< 0.001), greater ACV (AL:ACV 0.65 (< 0.001) and steeper corneal radii (AL:R1ant; R2ant; R1post; R2post 0.40; 0.35; 0.36; 0.36 (all with (< 0.001)). Spherical equivalent was associated with age (towards hyperopia: 0.34 (< 0.001)), AL (−0.66 (< 0.001)), ACD (−0.52 (< 0.001)) and ACV (−0.46 (< 0.001)). Accommodation was found lower for older subjects (negative association with age, r = −0.82 (< 0.001)) and contrast sensitivity presented with smaller values for older ages (AULCSF −0.38, (< 0.001)), no change of retinal thickness with age. 58 % of the study cohort presented with a change of refractive correction above ±0.50 D in one or both eyes (64 % of these were habitual spectacle wearers), need for improvement was present in the young age-group and for older subjects with increasing age. Conclusion: Biometrical data of healthy German eyes, stratified by age, gender and refractive status, enabled cross-comparison of all parameters, providing an important reference database for future patient-based research and specific in-depth investigations of biometric data in epidemiological research. Trial registration: ClinicalTrials.gov # NCT01173614 July 28, 2010
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Sahin, Serkan. "A Comparative Study Of Aisc-360 And Eurocode 3 Strength Limit States." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/12610894/index.pdf.
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Nowadaysdesign, fabrication and erection of steel structures can be taken place at different locations as a result of rapid globalization
owners may require the use of widely accepted steel design codes. Therefore, engineers are faced with the challenge of being competent with several design specifications for a particular material type. AISC-360 and EC3 are widely accepted steel structure design specifications that utilize limit state principles with some similarities and differences in application. Hereby a study has been undertaken to put together the nominal strength expressions presented in both AISC-360 and EC3 codes in a single document, to identify the similarities and the differences in calculated strengths and to facilitate rapid learning of either of the specifications with prior knowledge of the other. Because of the wide scope of specifications, only fundamental failure modes are considered in this thesis. Resistance equations are directly compared with each other wherever possible. For cases where the treatment of specifications is entirely different, representative members were considered for comparison purposes.
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Lasch, Alexander. "Nicoline Hortzitz, Die Sprache der Judenfeindschaft in der frühen Neuzeit (1450–1700): Untersuchungen zu Wortschatz, Text und Argumentation." De Gruyter, 2006. https://tud.qucosa.de/id/qucosa%3A74905.
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Die Sprache der Judenfeindschaft in der frühen Neuzeit (1450–1700) steht im „Grenzbereich zwischen sprach- und kulturwissenschaftlicher Antisemitismusforschung“, die die „zeittypischen Argumentationsstrategien, Begründungsmuster und sprachlichen Darstellungsmittel in antijüdischen Schriften“ der Frühen Neuzeit in den Blick nimmt, um die „Zusammenhänge von vormodernem (religiösem) ,Antijudaismus‘ und modernem (rassistisch-säkularem) ,Antisemitismus‘“ zu erhellen (Klappentext). Methodisch ruht die Studie auf einer Verschränkung zwischen struktureller Semantik und einer die Argumentationsstrukturen hervorhebenden Textlinguistik auf. Sie knüpft damit unmittelbar an die Vorarbeiten von Nicoline Hortzitz an, die in der Sprache der Judenfeindschaft die Ergebnisse ihrer Dissertation zum Früh-Antisemitismus (1988), der Monographie Judenarzt (1994) und diverser Aufsätze in einer „Gesamtbewertung der Befunde“ (S. V) vorlegt. In seiner Besprechung der Dissertation zum Früh-Antisemitismus merkte Matthias Richter kritisch an, daß „infolge des strukturalistischen Ansatzes die individuellen Differenzen zwischen den untersuchten Autoren zu sehr vernachlässigt werden.“¹ Die „minuziöse[] und aufwendige[] Systematisierung des sprachlichen Instrumentariums der Früh-Antisemiten“² setzt die vorliegende Monographie in der Ausweitung des Untersuchungszeitraums fort, ohne dabei jedoch eine „strukturelle Untersuchung“ liefern zu wollen, wie die Akzentverschiebung im Titel nahe zu legen scheint.
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Steinbach, Peter. "A Cross Section Measurement Of Events With Two Muons At The $Z^{0}$ Resonance And At Least One Heavy Flavour Jet At The ATLAS Experiment Of The Large Hadron Collider." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-95532.
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In 2010, the Large Hadron Collider (\\lhc{}) at the European Organisation for Nuclear Research (CERN) near Geneva (Switzerland) came into full operation providing proton-proton collisions at a centre-of-mass energy of $\\sqrt{s} = \\unit[7]{TeV}$. \\lhc{} data may allow the observation of the Higgs boson, the last unknown building block of the standard model of particle physics (SM). Di-muon final states containing heavy flavour jets pose an irreducible background for searches of the Higgs boson as predicted the SM or theories beyond. They also provide a unique testbed for tests of perturbative Quantum Chromo-Dynamics (pQCD). This thesis provides a measurement of the cross section of events with one di-muon pair with an invariant mass in the \\Z{} mass region and at least one heavy flavour jet. Studies on acceptance and systematic effects of the experimental setup are presented as well as a comparison to theoretical predictions. The total inclusive cross section of \\zbFS{} events was observed as $\\sigma(\\mu^{+}\\mu^{-}+b+X) = \\unit[(4.15 ^{+0.97}_{-0.89} (stat.) ^{+0.45}_{-0.53} (syst.))]{pb} $ from the equivalent of $\\unit[36]{pb^{-1}}$ of data. Agreement with pQCD predictions at next-to leading order (NLO) is found while tensions with leading order (LO) predictions are observed. Further, the cross-section ratio \\RwZ{} with events containing two muons and at least one jet of any origin was measured to $\\mathcal{R} = \\unit[4.6 ^{+1.4}_{-1.2} (stat.) \\pm 0.5 (syst.)]{\\%}$. This is found to agree with NLO and LO calculations within known uncertainties.
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Tackett, Bailey Price. "Psychosocial Predictors of Eating Disorder Classification: Longitudinal and Cross-Sectional Analyses." Thesis, University of North Texas, 2018. https://digital.library.unt.edu/ark:/67531/metadc1248447/.
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There is growing concern for eating pathology and body dissatisfaction in sports; particularly, in sports that emphasize a lean body type. In 325 female collegiate swimmers/divers and gymnasts, we examined psychosocial well-being (i.e., perception of weight pressures, levels of internalization, body satisfaction, dietary intent, negative affect) at the beginning and end of an athletic season and predict their eating disorder classification at the end of their athletic season. Logistic regressions revealed that a model containing all 14 predictors at the beginning and end of an athletic season significantly predicted eating disorder classification at the end of an athletic season. Specifically, in the longitudinal logistic regression, with every one unit of increase on a measure of the pressure felt within the sport environment regarding their weight and every unit increase on a measure of their intentions to diet, respectively, the female athletes were 49% and 89% more likely to be classified in the subclinical/clinical group at the end of their sport season. Surprisingly, with every one unit of increase on a measure of sociocultural pressure to exercise, female athletes were 43% less likely to be classified in the subclinical/clinical group six months later. The cross-sectional logistic regression found that only dietary restraint was significant. Specifically, with every one unit of increase on a measure of their intentions to diet the female athletes were 3.6 times more likely to be classified in the subclinical/clinical group at the end of their sport season. The implications of this study may emphasize the importance of body healthy sport systems to reduce sport specific pressures and dieting among female collegiate athletes. Limitations of this study include self-report measures and longitudinal timeframe was only across one athletic season.
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Geser, Felix. "Die Frage nach dem niedergelassenen Vertragsarzt als Beauftragter der Krankenkassen im Sinne des § 299 Strafgesetzbuch (Bestechlichkeit und Bestechung im geschäftlichen Verkehr)." Thesis, Dresden International University, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-224798.
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Gegen niedergelassene Kassenärzte wurden Ermittlungsverfahren wegen Bestechlichkeit im geschäftlichen Verkehr seit dem obiter dictum des Oberlandesgerichts Braunschweig im Jahr 2010 eingeleitet. In dieser Arbeit wird die Frage der Anwendbarkeit des § 299 Strafgesetzbuch auf den Vertragsarzt diskutiert. Zudem werden entsprechende Lösungsansätze nach geltendem bzw. zu schaffendem Recht dargestellt. Im Ergebnis gelten die Vertragsärzte nicht als geschäftlich Beauftrage der Krankenkassen bzw. Amtsträger. Es sollte jedoch auf das besondere „Vertragsverhältnis“ zwischen Arzt und Patient, das letztlich auf Vertrauen gründet, Rekurs genommen werden. Wenn gegenseitiges Vertrauen besteht, wird sich der Arzt in seinen diagnostischen und therapeutischen Entscheidungen nicht an seinen eigenen wirtschaftlichen Interessen bzw. Vorteilen orientieren, sondern sich zum Wohle des Patienten vom Facharztstandard unter Berücksichtigung des Wirtschaftlichkeitsgebots leiten lassen.
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NOVAES, ANDRE LUIZ FARIAS. "ECONOMETRIC GENETIC PROGRAMMING: A NEW APPROACH FOR REGRESSION AND CLASSIFICATION PROBLEMS IN CROSS-SECTIONAL DATASETS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2015. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=25338@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIROCONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO
Esta dissertação propõe modelos parcimoniosos para tarefas de regressão e classificação em conjuntos de dados exclusivamente seccionais, mantendo-se a hipótese de amostragem aleatória. Os modelos de regressão são lineares, estimados por Mínimos Quadrados Ordinários resolvidos pela Decomposição QR, apresentando solução única sob posto cheio ou não da matriz de regressores. Os modelos de classificação são não lineares, estimados por Máxima Verossimilhança utilizando uma variante do Método de Newton, nem sempre apresentando solução única. A parcimônia dos modelos de regressão é fundamentada na prova matemática de que somente agregará acurácia ao modelo o regressor que apresentar módulo da estatística de teste, em um teste de hipótese bicaudal, superior à unidade. A parcimônia dos modelos de classificação é fundamentada em significância estatística e embasada intuitivamente no resultado teórico da existência de classificadores perfeitos. A Programação Genética (PG) realiza o processo de evolução de modelos, explorando o espaço de busca de possíveis modelos, constituídos de distintos regressores. Os resultados obtidos via Programação Genética Econométrica (PGE) – nome dado ao algoritmo gerador de modelos – foram comparados aos proporcionados por benchmarks em oito distintos conjuntos de dados, mostrando-se competitivos em termos de acurácia na maior parte dos casos. Tanto sob o domínio da PG quanto sob o domínio da econometria, a PGE mostrou benefícios, como o auxílio na identificação de introns, o combate ao bloat por significância estatística e a geração de modelos econométricos de elevada acurácia, entre outros.
This dissertation proposes parsimonious models for regression and classification tasks in cross-sectional datasets under random sample hypothesis. Regression models are linear in parameters, estimated by Ordinary Least Squares solved by QR Decomposition, presenting a unique solution under full rank of the regressor matrix or not. Classification models are nonlinear in parameters, estimated by Maximum Likelihood, not always presenting a unique solution. Parsimony in regression models is based on the mathematical proof that accuracy will be added to models only by the regressor that presents a test statistic module higher than a predefined value in a two-sided hypothesis test. Parsimony in classification models is based on statistical significance and, intuitively, on the theoretical result about the existence of perfect classifiers. Genetic Programming performs the evolution process of models, being responsible for exploring the search space of possible regressors and models. The results obtained with Econometric Genetic Programming – name of the algorithm in this dissertation – was compared with those from benchmarks in eight distinct cross-sectional datasets, showing competitive results in terms of accuracy in most cases. Both in the field of Genetic Programming and in that of econometrics, Econometric Genetic Programming has shown benefits such as help on introns identification, combat to bloat by statistical significance and generation of high level accuracy models, among others.
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Pisane, Jonathan. "Automatic target recognition using passive bistatic radar signals." Phd thesis, Supélec, 2013. http://tel.archives-ouvertes.fr/tel-00963601.
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We present the design, development, and test of three novel, distinct automatic target recognition (ATR) systems for the recognition of airplanes and, more specifically, non-cooperative airplanes, i.e. airplanes that do not provide information when interrogated, in the framework of passive bistatic radar systems. Passive bistatic radar systems use one or more illuminators of opportunity (already present in the field), with frequencies up to 1 GHz for the transmitter part of the systems considered here, and one or more receivers, deployed by the persons managing the system, and not co-located with the transmitters. The sole source of information are the signal scattered on the airplane and the direct-path signal that are collected by the receiver, some basic knowledge about the transmitter, and the geometrical bistatic radar configuration. The three distinct ATR systems that we built respectively use the radar images, the bistatic complex radar cross-section (BS-RCS), and the bistatic radar cross-section (BS-RCS) of the targets. We use data acquired either on scale models of airplanes placed in an anechoic, electromagnetic chamber or on real-size airplanes using a bistatic testbed consisting of a VOR transmitter and a software-defined radio (SDR) receiver, located near Orly airport, France. We describe the radar phenomenology pertinent for the problem at hand, as well as the mathematical underpinnings of the derivation of the bistatic RCS values and of the construction of the radar images.For the classification of the observed targets into pre-defined classes, we use either extremely randomized trees or subspace methods. A key feature of our approach is that we break the recognition problem into a set of sub-problems by decomposing the parameter space, which consists of the frequency, the polarization, the aspect angle, and the bistatic angle, into regions. We build one recognizer for each region. We first validate the extra-trees method on the radar images of the MSTAR dataset, featuring ground vehicles. We then test the method on the images of the airplanes constructed from data acquired in the anechoic chamber, achieving a probability of correct recognition up to 0.99.We test the subspace methods on the BS-CRCS and on the BS-RCS of the airplanes extracted from the data acquired in the anechoic chamber, achieving a probability of correct recognition up to 0.98, with variations according to the frequency band, the polarization, the sector of aspect angle, the sector of bistatic angle, and the number of (Tx,Rx) pairs used. The ATR system deployed in the field gives a probability of correct recognition of $0.82$, with variations according to the sector of aspect angle and the sector of bistatic angle.
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Makki, Sara. "An Efficient Classification Model for Analyzing Skewed Data to Detect Frauds in the Financial Sector." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSE1339/document.
Full textAbstract:
Différents types de risques existent dans le domaine financier, tels que le financement du terrorisme, le blanchiment d’argent, la fraude de cartes de crédit, la fraude d’assurance, les risques de crédit, etc. Tout type de fraude peut entraîner des conséquences catastrophiques pour des entités telles que les banques ou les compagnies d’assurances. Ces risques financiers sont généralement détectés à l'aide des algorithmes de classification. Dans les problèmes de classification, la distribution asymétrique des classes, également connue sous le nom de déséquilibre de classe (class imbalance), est un défi très commun pour la détection des fraudes. Des approches spéciales d'exploration de données sont utilisées avec les algorithmes de classification traditionnels pour résoudre ce problème. Le problème de classes déséquilibrées se produit lorsque l'une des classes dans les données a beaucoup plus d'observations que l’autre classe. Ce problème est plus vulnérable lorsque l'on considère dans le contexte des données massives (Big Data). Les données qui sont utilisées pour construire les modèles contiennent une très petite partie de groupe minoritaire qu’on considère positifs par rapport à la classe majoritaire connue sous le nom de négatifs. Dans la plupart des cas, il est plus délicat et crucial de classer correctement le groupe minoritaire plutôt que l'autre groupe, comme la détection de la fraude, le diagnostic d’une maladie, etc. Dans ces exemples, la fraude et la maladie sont les groupes minoritaires et il est plus délicat de détecter un cas de fraude en raison de ses conséquences dangereuses qu'une situation normale. Ces proportions de classes dans les données rendent très difficile à l'algorithme d'apprentissage automatique d'apprendre les caractéristiques et les modèles du groupe minoritaire. Ces algorithmes seront biaisés vers le groupe majoritaire en raison de leurs nombreux exemples dans l'ensemble de données et apprendront à les classer beaucoup plus rapidement que l'autre groupe. Dans ce travail, nous avons développé deux approches : Une première approche ou classifieur unique basée sur les k plus proches voisins et utilise le cosinus comme mesure de similarité (Cost Sensitive Cosine Similarity K-Nearest Neighbors : CoSKNN) et une deuxième approche ou approche hybride qui combine plusieurs classifieurs uniques et fondu sur l'algorithme k-modes (K-modes Imbalanced Classification Hybrid Approach : K-MICHA). Dans l'algorithme CoSKNN, notre objectif était de résoudre le problème du déséquilibre en utilisant la mesure de cosinus et en introduisant un score sensible au coût pour la classification basée sur l'algorithme de KNN. Nous avons mené une expérience de validation comparative au cours de laquelle nous avons prouvé l'efficacité de CoSKNN en termes de taux de classification correcte et de détection des fraudes. D’autre part, K-MICHA a pour objectif de regrouper des points de données similaires en termes des résultats de classifieurs. Ensuite, calculez les probabilités de fraude dans les groupes obtenus afin de les utiliser pour détecter les fraudes de nouvelles observations. Cette approche peut être utilisée pour détecter tout type de fraude financière, lorsque des données étiquetées sont disponibles. La méthode K-MICHA est appliquée dans 3 cas : données concernant la fraude par carte de crédit, paiement mobile et assurance automobile. Dans les trois études de cas, nous comparons K-MICHA au stacking en utilisant le vote, le vote pondéré, la régression logistique et l’algorithme CART. Nous avons également comparé avec Adaboost et la forêt aléatoire. Nous prouvons l'efficacité de K-MICHA sur la base de ces expériences. Nous avons également appliqué K-MICHA dans un cadre Big Data en utilisant H2O et R. Nous avons pu traiter et analyser des ensembles de données plus volumineux en très peu de tempsThere are different types of risks in financial domain such as, terrorist financing, money laundering, credit card fraudulence and insurance fraudulence that may result in catastrophic consequences for entities such as banks or insurance companies. These financial risks are usually detected using classification algorithms. In classification problems, the skewed distribution of classes also known as class imbalance, is a very common challenge in financial fraud detection, where special data mining approaches are used along with the traditional classification algorithms to tackle this issue. Imbalance class problem occurs when one of the classes have more instances than another class. This problem is more vulnerable when we consider big data context. The datasets that are used to build and train the models contain an extremely small portion of minority group also known as positives in comparison to the majority class known as negatives. In most of the cases, it’s more delicate and crucial to correctly classify the minority group rather than the other group, like fraud detection, disease diagnosis, etc. In these examples, the fraud and the disease are the minority groups and it’s more delicate to detect a fraud record because of its dangerous consequences, than a normal one. These class data proportions make it very difficult to the machine learning classifier to learn the characteristics and patterns of the minority group. These classifiers will be biased towards the majority group because of their many examples in the dataset and will learn to classify them much faster than the other group. After conducting a thorough study to investigate the challenges faced in the class imbalance cases, we found that we still can’t reach an acceptable sensitivity (i.e. good classification of minority group) without a significant decrease of accuracy. This leads to another challenge which is the choice of performance measures used to evaluate models. In these cases, this choice is not straightforward, the accuracy or sensitivity alone are misleading. We use other measures like precision-recall curve or F1 - score to evaluate this trade-off between accuracy and sensitivity. Our objective is to build an imbalanced classification model that considers the extreme class imbalance and the false alarms, in a big data framework. We developed two approaches: A Cost-Sensitive Cosine Similarity K-Nearest Neighbor (CoSKNN) as a single classifier, and a K-modes Imbalance Classification Hybrid Approach (K-MICHA) as an ensemble learning methodology. In CoSKNN, our aim was to tackle the imbalance problem by using cosine similarity as a distance metric and by introducing a cost sensitive score for the classification using the KNN algorithm. We conducted a comparative validation experiment where we prove the effectiveness of CoSKNN in terms of accuracy and fraud detection. On the other hand, the aim of K-MICHA is to cluster similar data points in terms of the classifiers outputs. Then, calculating the fraud probabilities in the obtained clusters in order to use them for detecting frauds of new transactions. This approach can be used to the detection of any type of financial fraud, where labelled data are available. At the end, we applied K-MICHA to a credit card, mobile payment and auto insurance fraud data sets. In all three case studies, we compare K-MICHA with stacking using voting, weighted voting, logistic regression and CART. We also compared with Adaboost and random forest. We prove the efficiency of K-MICHA based on these experiments
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Chen, Hui. "Identification and classification of shareable tacit knowledge associated with experience in the Chinese software industry sector." Thesis, Loughborough University, 2015. https://dspace.lboro.ac.uk/2134/19659.
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The study reported in this thesis aimed to provide an ontology of professional activities in the software industry that require and enable the acquisition of experience and that, in turn, is the basis for tacit knowledge creation. The rationale behind the creation of such an ontology was based on the need to externalise this tacit knowledge and then record such externalisations so that these can be shared and disseminated across organisations through electronic records management. The research problem here is to conciliate highly theoretical principles associated with tacit knowledge and the ill-defined and quasi-colloquial concept of experience into a tool that can be used by more technical and explicit knowledge minded practitioners of electronic records management. The ontology produced and proposed here provides exactly such a bridge, by identifying what aspects of professional and personal experience should be captured and organising these aspects into an explicit classification that can be used to capture the tacit knowledge and codify it into explicit knowledge. Since such ontologies are always closely related to actual contexts of practice, the researcher decided to choose her own national context of China, where she had worked before and had good guarantees of industrial access. This study used a multiple case-study Straussian Grounded Theory inductive approach. Data collection was conducted through semi-structured interviews in order to get direct interaction with practitioners in the field and capture individuals opinions and perceptions, as well as interpret individuals understandings associated with these processes. The interviews were conducted in three different and representative types of company (SMEs, State Owned and Large Private) in an attempt to capture a rich variety of possible contexts in the SW sector in a Chinese context. Data analysis was conducted according to coding the procedures advocated by Grounded Theory, namely: open, axial and selective coding. Data collection and analysis was conducted until the emergent theory reached theoretical saturation. The theory generated identified 218 different codes out of 797 representative quotations. These codes were grouped and organised into a category hierarchy that includes 6 main categories and 31 sub-categories, which are, in turn, represented in the ontology proposed. This emergent theory indicates in a very concise manner that experienced SW development practitioners in China should be able to understand the nature and value of experience in the SW industry, effectively communicate with other stake holders in the SW development process, be able and motivated to actively engage with continuous professional development, be able to share knowledge with peers and the profession at large, effectively work on projects and exhibit a sound professional attitude both internally to their own company and externally to customers, partners and even competitors. This basic theory was then further analysed by applying selective coding. This resulted in a main theory centred on Working in Projects, which was clearly identified as the core activity in the SW Industry reflecting its design and development nature. Directly related with the core category, three other significant categories were identified as enablers: Communication, Knowledge Sharing and Individual Development. Additionally, Understanding the Nature of Experience in the SW Industry and Professional Attitude were identified as drivers for the entire process of reflection, experience acquisition and tacit knowledge construction by the individual practitioners. Finally, as an integral part of any inductive process of research, the final stage in this study was to position the emerged theory in the body of knowledge. This resulted in the understanding that the theory presented in this study bridges two extremely large bodies of literature: employability skills and competencies. Both of these bodies of literature put their emphasis in explicit knowledge concerning skills and competencies that are defined so that they can be measured and assessed. The focus of the theory proposed in this thesis on experience and resulting acquisition of tacit knowledge allows a natural link between the employability skills and competencies in the SW industry that was hitherto lacking in the body of knowledge. The ontology proposed is of interest to academics in the areas of knowledge management, electronic records management and information systems. The same ontology may be of interest to human resources practitioners to select and develop experienced personnel as well as knowledge and information professionals in organisations.
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Luther, Stephan. "Sind wir fit für das 21. Jahrhundert? : Die aus den neuen Technologien erwachsenden Anforderungen an die Archive." Universitätsverlag der Technischen Universität Chemnitz, 2011. https://monarch.qucosa.de/id/qucosa%3A19404.
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Der Tagungsband beschäftigt sich mit den aus den neuen Technologien erwachsenden Anforderungen an die Archive. Er fasst mehrere Aufsätze zusammen, die sich aus unterschiedlichen Perspektiven mit diesen Herausforderungen beschäftigen. Das Eingangsreferat von Norbert Becker wertet eine Umfrage zu Erwartungen der Benutzer im Hinblick auf die modernen Medien und Informationstechnologien aus. Kerstin Arnold stellt das Projekt zur Schaffung eines Archivportals für die Bundesrepublik Deutschland vor. In zwei weiteren Beiträgen werden konkrete Digitalisierungsprojekte bzw. –strategien vorgestellt. Susanne Knoblich, Berlin, stellt einen Werkstattbericht zur Übernahme von elektronischen Unterlagen in das Landesarchiv Berlin vor. Abgerundet wird der Band durch einen Beitrag von Kerstin Orantek zu den Problemen des Datenschutzes in einer digitalisierten Welt.:Stephan Luther: Einleitung 7
Norbert Becker: Perspektiven, Benutzererwartungen und neue Aufgaben
der Archive zu Beginn des 21. Jahrhunderts. Ergebnisse einer Benutzerumfrage 11
Kerstin Arnold: Auf dem Weg zum Archivportal Deutschland. Die Referenzanwendung aus dem DFG-Projekt zum „Ausbau des Netzwerks
SED-/FDGB-Archivgut“ 37
Marek Ďurčanský: Die tschechischen Spezialarchive und die Digitalisierung 53
Matthias Röschner: Auf dem Weg ins Internet – Digitalisierungsprojekte im Archiv 65
Susanne Knoblich: Übernahme und Archivierung elektronischer Unterlagen
durch das Landesarchiv Berlin – Ein Werkstattbericht 83
Kerstin Orantek: Probleme des Datenschutzes in einer digitalisierten
Welt – Neue Anforderungen für Archive? 91The proceedings of the conference are concerned with the requirements for archives arising due to new technologies. It comprises several papers addressing these challenges from different perspectives. The opening address by Norbert Becker evaluates a survey on user expectations concerning modern media and information technologies. Kerstin Arnold describes a project to create the archive portal of the Federal Republic of Germany. In two other contributions, specific digitisation projects or strategies are discussed. Susanne Knoblich from Berlin presents a working report on the transfer of electronic documents for the National Archives of Berlin. Kerstin Orantek completes the volume with a contribution on the problem of data protection in a digital world.:Stephan Luther: Einleitung 7 Norbert Becker: Perspektiven, Benutzererwartungen und neue Aufgaben der Archive zu Beginn des 21. Jahrhunderts. Ergebnisse einer Benutzerumfrage 11 Kerstin Arnold: Auf dem Weg zum Archivportal Deutschland. Die Referenzanwendung aus dem DFG-Projekt zum „Ausbau des Netzwerks SED-/FDGB-Archivgut“ 37 Marek Ďurčanský: Die tschechischen Spezialarchive und die Digitalisierung 53 Matthias Röschner: Auf dem Weg ins Internet – Digitalisierungsprojekte im Archiv 65 Susanne Knoblich: Übernahme und Archivierung elektronischer Unterlagen durch das Landesarchiv Berlin – Ein Werkstattbericht 83 Kerstin Orantek: Probleme des Datenschutzes in einer digitalisierten Welt – Neue Anforderungen für Archive? 91
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Grabow, Gerd. "Zum 175. Geburtstag Alfred Wilhelm Stelzners, eines verdienstvollen Wissenschaftlers auf dem Gebiet der Geologie und der Lagerstättenlehre." ACAMONTA 22(2015), 2015. https://tubaf.qucosa.de/id/qucosa%3A23082.
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GLANS, GUSTAV, and JESPER ROSENBERG. "Improving Measurement of SectorConcentration Risk in Credit Portfolios : Evaluation of sector classification and approaches to concentration measure characteristics." Thesis, KTH, Entreprenörskap och Innovation, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-189498.
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På en teknisk nivå utgör beräkningen av sektorkoncentrationsrisk ett särskilt utmanande problem. I befintlig teori är riktlinjer till såväl hur industrisektorer ska indelas som risknivån beräknas begränsade. Syftet med studien är att utvärdera och analysera olika tillvägagångssätt till sektorkoncentrationsrisk i kreditportföljer. Detta har utförts i två separata delar där både indelningen i sektorer och riskberäkningen behandlats. Sektorindelningen har utvärderats genom att jämföra korrelationsstrukturen mellan två speciellt intressanta indelningsmetodiker; enligt Morgan Stanely Capital Investment (MSCI) och den av Finansinspektionen föreslagna sektorindelningen (SFSA). Riskberäkningen har utvärderats genom att applicera en rad olika koncentrationsmått på portföljer av varierande koncentrationsgrad. Resultaten visar att en minimering av inter-sektoriella korrelationer samt en maximering av intra-sektoriella korrelation är av stor vikt då sektorer indelas. Med andra ord, för att koncentrationen ska generera en faktisk risk krävs det att sektorerna är tydligt särskilda samt internt homogena. Utöver detta ska individuella exponeringar tydligt kunna placeras inom en sektor och de behandlade sektorerna ska inte vara av diversifierad natur. Resultaten tyder vidare på att MSCI presterar bättre för att hantera sektorkoncentrationsrisk på alla dessa punkter. När det kommer till riskberäkningen, visar resultaten att förutom ördelningen av exponeringar är även sektorspecifika kreditkvaliteter samt korrelationsstrukturer av vikt för att bestämma risknivån. Risken från koncentration är större om risknivån är hög eller om exponeringen är mot korrelerade sektorer. Men framförallt tyder resultaten på att en uniformt fördelat portfölj inte är att se som okoncentrerad. För att ta hänsyn till naturliga koncentrationer är det därför av yttersta vikt att koncentration istället ses i förhållande till den aggregerade kreditmarknaden.On a technical level, the measurement of sector concentration risk poses a particularlychallenging problem. Existing literature lacks direct suggestions both regarding how sectors are to be divided and the risk-level measured. The purpose of the study is to evaluate and analyse different measures of - and approaches to sector concentration risk in credit portfolios. This has been addressed both by analysing sectorial division and which aspects that are of interest for determining the concentration imposed risk- level. The sectorial division has been addressed by comparing the correlation structures of two especially interesting sector classification methods; the standardised Morgan Stanley Capital Investment industry classification (MSCI) and the proposed sector classification of the Swedish Financial Supervisory Authority (SFSA). The sector concentration risk measurement has been analysed through employing different risk-measures on portfolios with varying concentration levels. The results show that in order to capture the risk-level from concentration, the main approach for sectorial division should seek to minimise inter-sector correlations and maximise intra-sector correlations. I.e. sectors should be distinct from each other and internally homogeneous. Moreover, an unambiguous sorting of individual exposures towards one sector should be possible and the considered sectors should not be of a diversified nature. It is also found that MSCI outperforms SFSA for assessing sector concentration risk on all fronts. When it comes to the risk measure, it is found that apart from exposure distribution; credit qualities and correlation structures are of great interest. The risk induced from a concentrated exposure is greater if credit qualities are low or if the exposure is high towards highly correlated sectors. But above all, the results imply that a uniform distribution is not to be seen as unconcentrated. In order for concentration measurement to incorporate natural concentrations it is thereby greatly important that concentration instead is considered as relative towards the aggregate credit market.
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Jonsson, Sebastian. "Manufacturing and Service sector R&D : Significantly different." Thesis, KTH, Entreprenörskap och Innovation, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-169921.
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The purpose of this thesis is to investigate differences in the R&D motivations for manufacturing and service firms. The thesis contributes to existing R&D literature as it proposes a novel approach for the categorization of manufacturing and service firms. Using data from the Statistics Sweden R&D survey, the paper classifies firms according to their income structure, which allows the study to base industry classifications to what best aligns with firms’ actual activities. The methodology consists of Welch’s two- sample t-test in combination with OLS regressions to examine differences in the motivations for manufacturing and service firms. The results suggest that there is a statistically significant difference in the motivations. Manufacturing firms are found to devote a higher proportion of their total R&D investments towards the improvement of existing products. Services were found to devote a greater share of their R&D investments to the development of new processes and to increases in general knowledge-building. Moreover, the study finds a substantial disparity in how firms are classified according to industry classification codes and how they actually earn their revenues and therefore questions the accuracy of conventional industry classification methods.
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Breitwieser, Matthias, Friedemann D. Heinz, Andreas Büchler, Martin Kasemann, Jonas Schön, Wilhelm Warta, and Martin C. Schubert. "Analysis of solar cell cross sections with micro-light beam induced current (µLBIC)." Elsevier, 2014. https://publish.fid-move.qucosa.de/id/qucosa%3A72456.
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A highly resolving micro-light beam-induced current (µLBIC)-system is presented in this work. Based on the laser excitation via an optical microscope, current values can be measured with sub-micron precision. We show, that this non-destructive, light-based approach delivers superior results to a reference electron microscope based electron beam induced current method concerning contrast and robustness towards reflection differences, whereas no vacuum is needed, no charging effects can occur and equal resolution is achieved. µLBIC allows therefore mapping of pn-junctions at silicon solar cell cross sections. By combination of µLBIC with other measurement methods in the same setup, such as micro-Raman spectroscopy, complementary microscopic information about material stress or crystallinity and electronic properties at the same region of interest on the sample is revealed. By applying µLBIC for analyzing silicon solar cross sections, two characterization examples of current technological relevance are presented: enhanced dopant diffusion along grain boundaries between grains with different orientations is quantified and the impact of a nickel silicide spike on local charge collection quality is studied.
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Wittgren, Bengt. "Katalogen – nyckeln till museernas kunskap? : Om dokumentation och kunskapskultur i museer." Doctoral thesis, Umeå universitet, Institutionen för kultur- och medievetenskaper, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-80093.
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In the 1990s, the MLA sector – archives, libraries, museums – was defined as a comprehensive sector. One of the reasons for this was the belief that the digitizing of institutional collections and catalogues would provide a seamless access to the cultural heritage for the general public. No one would any longer need to know in which institution a certain object was kept; everything would be available on the Internet. The questions in this dissertation depart from the expectations in the late 1900s aimed at the available systems in the MLA sector for the management and storage of information and at knowledge maintained in such systems. My point of departure is the idea that access to collections in the MLA sector – real or digital – is made possible through the catalogues. It is in the catalogues that the sector orders data and preserves knowledge collected about the objects. My most important conclusions deal with the management and production of knowledge in the sector. The data systems generally used in the MLA sector lack the indulgence needed to accommodate inherent variability of information. Systems must be based on exact sorting, uniform terminology and classification without deviations in spelling or interpretation. Furthermore, international projects and systems presuppose distinct translations between national terminologies and international classification systems to work for information retrievals. This is not the case with the museum systems here investigated, in opposition to, primarily, the libraries. The museum systems are characterised as distinctive instead of following uniformity principles and national or international taxonomies. An important conclusion about knowledge processing and knowledge production in the MLA sector is that the value of compiling digitalised data from many museums is limited. It is not possible to realize the political goal other than at a superficial level. The conclusions in a comparison between the three professional groups are that in the beginning of the 21th century an extensive part of the antiquarians confirm a thought style, according to Ludwik Fleck, which has another direction than that of archivists and librarians. Throughout the 20th century or in the last decades of the 20th century the two latter groups professionalised their roles both through changes in education and through new professional requirements which led to positions and attitudes in their work other than what happened in the museum sector. Museums are mainly research institutions with members of staff who in many respects lack a focus on increased accessibility of collections. Challenges formulated for museums of cultural history by the cultural politics of the 1970s have not been answered with great flexibility. The investigation in this dissertation demonstrates that archives, libraries and museums in many respects continue to pursue activities according to a thought style which was formed during the first half of the 20th century. Their positions in society, their administrational practice and expectations from the general public constitute stabilising and preserving factors. The MLA sector is not as comprehensive as the policy makers want to believe.
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Denk, Martin, Klemens Rother, and Kristin Paetzold. "Beam-colored Sketch and Image-based 3D Continuous Wireframe Reconstruction with different Materials and Cross-Sections." Thelem Universitätsverlag & Buchhandlung GmbH & Co. KG, 2021. https://tud.qucosa.de/id/qucosa%3A75878.
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The automated reverse engineering of wireframes is a common task in topology optimization, fast concept design, bionic and point cloud reconstruction. This article deals with the usage of skeleton-based reconstruction of sketches in 2D images. The result leads to a flexible at least C₁ continuous shape description.
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Lachner, Gabriele, Hans-Ulrich Wittchen, Axel Perkonigg, Alexandra Holly, Peter Schuster, Ursula Wunderlich, Dilek Türk, Ela Garczynski, and Hildegard Pfister. "Structure, Content and Reliability of the Munich-Composite International Diagnostic Interview (M-CIDI) Substance Use Sections." Karger, 1998. https://tud.qucosa.de/id/qucosa%3A26272.
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After reviewing currently available diagnostic assessment instruments for substance use disorders this paper describes the format and structure of the Munich-Composite International Diagnostic Interview (M-CIDI) substance disorder section. In addition, the test-retest reliability of diagnoses and criteria for nicotine, alcohol, illegal and prescription drugs, is reported. Findings obtained in community sample of adolescents and young adults indicate that the substance section is acceptable for almost all types of respondents, efficient in terms of time and ease of administration as well as reliable in terms of consistency of findings over time. The test-retest reliability over a period of an average of 1 month, as examined by two independent interviewers indicates good-to-excellent kappa values for all substance disorders assessed, with significant kappa values ranging between 0.55 for drug abuse and 0.83 for alcohol abuse. There was also fairly consistently high agreement for the assessment of single DSM-IV diagnostic criteria for abuse and dependence as well as the M-CIDI quantity-frequency and time-related questions. To conclude, although – unlike previous studies – this study was conducted in a community sample and not in patients and used considerably longer time intervals of more than a month between investigations, our M-CIDI reliability findings are at least as high as those from previous studies.
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Rekathati, Faton. "Curating news sections in a historical Swedish news corpus." Thesis, Linköpings universitet, Statistik och maskininlärning, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-166313.
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The National Library of Sweden uses optical character recognition software to digitize their collections of historical newspapers. The purpose of such software is first to automatically segment text and images from scanned newspaper pages, and second to read the contents of the identified text regions. While the raw text is often digitized successfully, important contextual information regarding whether the text constitutes for example a header, a section title or the body text of an article is not captured. These characteristics are easy for a human to distinguish, yet they remain difficult for a machine to recognize. The main purpose of this thesis is to investigate how well section titles in the newspaper Svenska Dagbladet can be classified by using so called image embeddings as features. A secondary aim is to examine whether section titles become harder to classify in older newspaper data. Lastly, we explore if manual annotation work can be reduced using the predictions of a semi-supervised classifier to help in the labeling process. Results indicate the use of image embeddings help quite substantially in classifying section titles. Datasets from three different time periods: 1990-1997, 2004-2013, and 2017 and onwards were sampled and annotated. The best performing model (Xgboost) achieved macro F1 scores of 0.886, 0.936 and 0.980 for the respective time periods. The results also showed classification became more difficult on older newspapers. Furthermore, a semi-supervised classifier managed an average precision of 83% with only single section title examples, showing promise as way to speed up manual annotation of data.
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Bramlage, Peter, David Pittrow, Hendrik Lehnert, Michael Höfler, Wilhelm Kirch, Eberhard Ritz, and Hans-Ulrich Wittchen. "Frequency of albuminuria in primary care: a cross-sectional study." Technische Universität Dresden, 2007. https://tud.qucosa.de/id/qucosa%3A26698.
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Background: We aimed to assess the point prevalence of microalbuminuria (MAU) in a sample of unselected consecutive primary-care attendees, with particular focus on patients with diabetes mellitus (with and without additional concomitant diseases) and those with hypertension.
Design: Cross-sectional observational study in a nationwide representative sample of 1912 primary-care practices and a patient population consisting of 39 125 primary-care attendees. Diagnoses for diabetes, hypertension and co-morbidities were provided by the treating physician and complemented by blood pressure (BP) measurements and selected lab tests. Screening for microalbuminuria (>20 and <200 μg/ml) was done with a spot urine dipstick test.
Results: The clinical diagnosis of nephropathy was assigned to 7.6% of patients. The point prevalence of MAU was 19.0% in the total sample; the proportion was 33.6% in diabetics whereas the diagnosis was assigned to only 7.1% in the total sample. Amongst diabetic patients with MAU, 92.6% had BP above the target value of < 130/80 mmHg. Frequency rates rose with increasing BP (e.g. 20.6% in diabetic patients with BP< 120/70 mmHg, and 36.3% in diabetic patients with BP > 140/90 mmHg). Of note, patients with MAU had a higher burden of co-morbidity compared to those without MAU.
Conclusions: We found a high prevalence of MAU in primary care, particularly in diabetic patients. The frequency of MAU was closely related to the BP level and the degree of co-morbidity. The present study underlines the magnitude of the problem of MAU in primary care, and should serve as a starting point to initiate measures to address this important public health issue.
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Zobelli, Alberto. "Electron beam generation and structure of defects in carbon and boron nitride nanotubes." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2007. http://nbn-resolving.de/urn:nbn:de:swb:14-1197988167199-13274.
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The nature and role of defects is of primary importance to understand the physical properties of C and BN single walled nanotubes. Transmission electron microscopy (TEM) is a well known powerful tool to study the structure of defects in materials. However, in the case of SWNTs, the electron irradiation of the TEM may knock out atoms. This effect may alter the native structure of the tube, and has also been proposed as a potential tool for nanoengineering of nanotubular structures. Here we develop a theoretical description of the irradiation mechanism. First, the anisotropy of the emission energy threshold is obtained via density functional based calculations. Then, we numerically derive the total Mott cross section for different emission sites of carbon and boron nitride nanotubes with different chiralities. Using a dedicated STEM microscope with experimental conditions optimised on the basis of derived cross-sections, we are able to control the generation of defects in nanotubular systems. Either point or line defects can be obtained with a spatial resolution of a few nanometers. The structure, energetics and electronics of point and line defects in BN systems have been investigated. Stability of mono- and di- vacancy defects in hexagonal boron nitride layers is investigated, and their activation energies and reaction paths for diffusion have been derived using the nudged elastic band method (NEB) combined with density functional based techniques. We demonstrate that the appearance of extended linear defects under electron irradiation is more favorable than a random distribution of point defects and this is due to the existence of preferential sites for atom emission in the presence of pre-existing defects, rather than thermal vacancy nucleation and migration.