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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
121

””Världens bästa planeringsprocess” - en analys av en informationsflödesprocess hos ett flygbolag på den skandinaviska marknaden / The Best Planning Process in the World” - an analysis of an information flow process within an airline operating in the Scandinavian market

Modin, Maria January 2014 (has links)
Detta projekt har utförts på ett charterflygbolag som verkar på den skandinaviska flygmarknaden, och är en första del i flygbolagets projekt (översatt till svenska) ”Världens bästa planeringsprocess”. ”Världens bästa planeringsprocess” skall kartlägga flygbolagets planeringsprocess sett till från det att en förfrågan kommer in till flygbolaget, till dess att ett svar kan lämnas till kunden. Detta projekt som behandlas i denna rapport studerar informationsflödesprocessen inom flygbolaget med fokus på den planering som sker efter att en kommande säsongs flygprogram är fastlagt. Det vill säga, detta projekt behandlar de förfrågningar som utgör förändringar och tillägg i flygprogrammet. Utifrån en kartläggning har informationsflödesprocessen analyserats utifrån Lean production-teori och tillämpbara åtgärder för att uppnå tidseffektivisering i flöden. Detta har sammanfattats i de följande möjliga åtgärderna för flygbolaget: - Omfördelning av flödet genom synkronisering, parallellisering och sekvensering - Omfördelning av arbetsuppgifter - Tillämpning av Alternate Chief Pilot Det rekommenderas att tillämpa samtliga åtgärdsförslag, vilket bedöms kunna ge en tidsbesparing på mellan 7 och 52 % i ledtid.
122

Second language learning in an online computer game insights from theories of social interaction, practice, and nonlinear dynamics /

Reese, Curtis Lee, January 1900 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2007. / Vita. Includes bibliographical references.
123

Μέθοδοι βελτίωσης της μεταβατικής ευστάθειας σύνθετων ηλεκτρικών συστημάτων εναλλασσόμενου - συνεχούς ρεύματος

Μάρης, Θεόδωρος 16 November 2009 (has links)
- / -
124

Behaviour of reinforced concrete frame structure against progressive collapse

Harry, Ofonime Akpan January 2018 (has links)
A structure subjected to extreme load due to explosion or human error may lead to progressive collapse. One of the direct methods specified by design guidelines for assessing progressive collapse is the Alternate Load Path method which involves removal of a structural member and analysing the structure to assess its potential of bridging over the removed member without collapse. The use of this method in assessing progressive collapse therefore requires that the vertical load resistance function of the bridging beam assembly, which for a typical laterally restrained reinforced concrete (RC) beams include flexural, compressive arching action and catenary action, be accurately predicted. In this thesis, a comprehensive study on a reliable prediction of the resistance function for the bridging RC beam assemblies is conducted, with a particular focus on a) the arching effect, and b) the catenary effect considering strength degradations. A critical analysis of the effect of axial restraint, flexural reinforcement ratio and span-depth ratio on compressive arching action are evaluated in quantitative terms. A more detailed theoretical model for the prediction of load-displacement behaviour of RC beam assemblies within the compressive arching response regime is presented. The proposed model takes into account the compounding effect of bending and arching from both the deformation and force points of view. Comparisons with experimental results show good agreement. Following the compressive arching action, catenary action can develop at a much larger displacement regime, and this action could help address collapse. A complete resistance function should adequately account for the catenary action as well as the arching effect. To this end, a generic catenary model which takes into consideration the strength degradation due to local failure events (e.g. rupture of bottom rebar or fracture of a steel weld) and the eventual failure limit is proposed. The application of the model in predicting the resistance function in beam assemblies with strength degradations is discussed. The validity of the proposed model is checked against predictions from finite element model and experimental tests. The result indicate that strength degradation can be accurately captured by the model. Finally, the above developed model framework is employed in investigative studies to demonstrate the application of the resistance functions in a dynamic analysis procedure, as well as the significance of the compressive arching effect and the catenary action in the progressive collapse resistance in different designs. The importance of an accurate prediction of the arching effect and the limiting displacement for the catenary action is highlighted.
125

Characterization of Two Novel Gene Regulatory Systems in the Zoonotic Bacterium <i>Bartonella henselae</i>

Tu, Nhan 19 November 2015 (has links)
The genus Bartonella contains Gram-negative arthropod-borne bacteria that are found in many small animal reservoirs and are capable of causing human disease. Bacteria utilize a general stress response system to combat stresses from their surrounding environments. In α-proteobacteria, the general stress response system uses an alternate σ factor as the main regulator and incorporates it with a two-component system into a unique system. Our study identifies the general stress response system in the α-proteobacterium, Bartonella henselae, where the gene synteny is conserved and both the PhyR and alternate σ factor have similar sequence and domain structures with other α-proteobacteria. Furthermore, we showed that the general stress response genes are up-regulated under conditions that mimic the cat flea vector. We also showed that both RpoE and PhyR positively regulate this system and that RpoE also affects transcription of genes encoding heme-binding proteins and the BadA adhesin. Finally, we also identified a histidine kinase, annotated as BH13820 that can potentially phosphorylate PhyR. In addition, analysis of the transcriptome from the Houston-1 strain of B. henselae by RNA-Seq reveals a family of small RNAs (termed Brt1-Brt9 for Bartonella Regulatory Transcripts 1-9) that may rapidly adapt gene expression patterns to the diverse hosts of this bacterium. This family of RNAs consists of nine novel, highly expressed intergenic transcripts, ranging from 193-205 nucleotides with a high degree of homology (70-100%) and stable predicted secondary structures that are unique to the genus Bartonella. Northern blot analysis indicates that transcription of these sRNAs was highest under conditions mimicking those of the cat flea vector (low temperature, high hemin). The predicted promoters for Brt1-Brt9 have been cloned upstream of a β-galactosidase reporter gene in pNS2 to identify conditions altering transcription. Immediately downstream of each of the nine putative sRNAs is a helix-turn-helix DNA binding protein (termed Trp1-9 for Transcriptional Regulatory Protein 1-9) that is poorly transcribed as determined by RNA-Seq. This gene organization is suggestive of a potential cis-acting RNA mechanism or riboswitch with the RNA secondary structure controlling transcription of the cognate downstream trp.
126

Improper Gaussian Signaling in Interference-Limited Systems

Gaafar, Mohamed 05 1900 (has links)
In the last decade, wireless applications have witnessed a tremendous growth. This can be envisioned in the surge of smart devices which became almost in everyone's possession, demand for high speed connection and the internet of things (IoT) along with its enabling technologies. Hence, the multiuser interference became the main limiting factor in wireless communications. Moreover, just like diamonds and emeralds, the electromagnetic spectrum is limited and precious. Therefore, the high data rate application may not be satisfied by our current technologies. In order to solve this spectrum scarcity problem, researchers have steered their focus to develop new techniques such as cognitive radio (CR) and in-band full-duplex (FD). However, these systems suffer from the interference problem that can dramatically impede their quality-of-service (QoS). Therefore, investigating communication techniques/systems that can relieve the interference adverse signature becomes imperative. Improper Gaussian signaling (IGS) has been recently shown to outperform the traditional proper Gaussian signaling (PGS) in several interference-limited systems. In this thesis, we use IGS in order to mitigate the interference issue in three different communication settings. IGS has the ability to control the interference signal dimension, and hence, it can be considered as one form of interference alignment. In the first part, we investigate an underlay CR system with in-band FD primary users (PUs) and one-way communication for the secondary user (SU). IGS is employed to alleviate the interference introduced by the SU on the PUs. First, we derive a closed form expression and an upper bound for the SU and PUs outage probabilities, respectively. Second, we optimize the SU signal parameters, represented in its power and the circularity coefficient, to achieve the design objectives of the SU while satisfying certain QoS constraints for the PU under instantaneous, average and partial channel state information (CSI). Finally, we provide some numerical results that demonstrate the advantages that can be reaped by using IGS to access the spectrum of the FD PUs. Specifically, with the existence of week PU direct channels and/or strong SU interference channels, PGS tends to use less transmit power while IGS uses more power along with increasing the signal impropriety. Part 2 studies the potential employment of IGS in FD cooperative settings with non-negligible residual self-interference (RSI). In this part, IGS is used in an attempt to alleviate the RSI adverse effect in full-duplex relaying (FDR). To this end, we derive a tight upper bound expression for the end-to-end outage probability in terms of the relay signal parameters. We further show that the derived upper bound is either monotonic or unimodal in the relay's circularity coefficient. This result allows for easily locating the global optimal point using known numerical methods. Based on the analysis, IGS allows FDR systems to operate even with high RSI. It is shown that, while the communication totally fails with PGS as the RSI increases, the IGS outage probability approaches a fixed value that depends on the channel statistics and target rate. The obtained results show that IGS can leverage higher relay power budgets than PGS to improve the performance, meanwhile it relieves its RSI impact via tuning the signal impropriety. In part 3, we investigate the potential benefits of adopting IGS in a two-hop alternate relaying (AR) system. Given the known benefits of using IGS in interference-limited networks, we propose to use IGS to relieve the inter-relay interference (IRI) impact on the AR system assuming no CSI is available at the source. In this regard, we assume that the two relays use IGS and the source uses PGS. Then, we optimize the degree of impropriety of the relays signal, measured by the circularity coefficient, to maximize the total achievable rate. Simulation results show that using IGS yields a significant performance improvement over PGS, especially when the first hop is a bottleneck due to weak source-relay channel gains and/or strong IRI.
127

Design automobilu na alternativní pohon / Design of alternate fuel vehicle

Chlíbek, Lukáš January 2008 (has links)
With this diploma project is my objective to evolve an idea of a skateboard platform includes all the components used for drive and design new system of changing several types of car bodies by using this platform and all with comprihension of social, economical and ecological requirements in the near future. By this concept am I trying to underline evolving potencional of skateboard platform system. Given target was to design a multipurpose family vehicle with alternate drive and sport characteristic, cute timeless design, maximal usage of inner space, using new technologies and materials and including of designing whole system of exchange car bodies depending on actual customer needs. Sense of designing is not to assume any of car brands, but design my own way of shaping. This diploma project is not proposed to current infrastructure because of an ecological drive and materials, but follows actual technical and design trends and shows presumed and requested evolution. Ephassis of this diploma project is forced mainly on functionality of all car body exchange system and for integration characteristic of MPV category in exterior and interior with sport timeless design at all.
128

Versioner av en berättelse : En narratologisk analys av Blade Runner / Versions of a story : A narrative analysis of Blade Runner

Skoting, Joel January 2020 (has links)
The purpose of this essay is to describe and examine the different versions of the 1982 movie Blade Runner. How these versions vary in question of narrative, theme, tone and message is a focal point of this essay. Of special interest is how these relate to our reality regarding political or philosphical views. The conclusion of this study is that the same core ideas and messages remain throughout the different versions of Blade Runner. However, the ways in which these ideas are presented vary, as does the tone of certain scenes. Through some censoring and editing, some themes are affected and are not as easily identified in all versions of the film. Some of these relate to symbolism through symbolic violence and how humans affect their environment. Other central themes relate to discrimination towards minorities and existential themes and questions. In conclusion: Blade Runner is a complex and topical movie which shifts in tone and theme depending on which version you view.
129

L’EMDR dans l’évolution de la prise en charge du TSPT : psychothérapie de la dissociation par les Stimulations Bilatérales Alternées Auditives / EMDR in the evolution of the treatment of PTSD : Psychotherapy of a dissociation by auditory alternated bilateral

Viard, Florent 08 December 2018 (has links)
Contexte scientifique : Les Stimulations Bilatérales Alternées (SBA) sont des techniques portant sur les modalités visuelles, tactiles ou auditives utilisées dans la psychothérapie EMDR « Eyes Movement Desensitization And Reprocessing ». Les recherches isolant les SBA portent souvent sur la modalité visuelle et relatent son effet sur la perturbation subjective à partir de la diminution de l'activité végétative observée. Or certains TSPT ne présentent pas d'activité végétative marquée, ceci corrélativement à la présence de dissociation (Choi et al., 2017; Sack, Cillien, & Hopper, 2012; Briere, Weathers, & Runtz, 2005) Aussi, peu d'études sont consacrées aux SBA auditives sauf pour signaler leur effet moindre comparativement aux autres modalités (Van Den Hout et al, 2012). Par ailleurs, le lien entre les SBA auditives et la dissociation n'a jamais fait l'objet de publication.Problématique : Quel est l'effet des SBA auditives sur l'intensité des signes de dissociation et de perturbation liées à un événement ?Méthode : Après avoir défini la dissociation comme un processus de perception du vécu subjectif qui échappe à la conscience, nous utilisons une méthode expérimentale incluant 40 participants volontaires pour offrir un argument en faveur de l’intérêt des SBA auditives dans le traitement de la dissociation. L'étude comprend 40 participants sains ayant une activité végétative stable pendant le rappel d'un souvenir inquiétant. Les sujets sont distribués au hasard pour la phase de traitement au cours de laquelle ils se rappellent l'événement simultanément à des SBA auditives (n = 20) ou sans SBA auditive (n = 20). L'intensité des signes de dissociation et de perturbation est mesurée en pré-traitement et post-traitement à partir des scores moyens dans le questionnaire RSDI «Response to script Driven imagerie» (Hopper et al, 2007). Résultats : Pour la dissociation, il y a une interaction significative entre les variables Groupe et Moment, F(1, 38) = 5.25, p= .03. Avec SBA auditives, on observe une différence des scores en pré et post traitement significative V = 134, n = 20, p = .03 ; dans le sens d'une diminution. Pour la perturbation subjective, il n'y a pas d'interaction significative entre les variables et la différence des scores n'est pas significative.Discussion : la technique SBA auditive diminue l'intensité des signes de dissociation. Cela ne génère pas forcément un vécu subjectif perturbant. Ces résultats préliminaires ouvrent un champ de recherche sur la psychopathologie dissociative et des SBA auditives. À partir des travaux de Stanislas Dehaene sur « l’espace de travail neuronal global » et la conscience, nous proposons un nouveau modèle théorique de l’action des SBA en intégrant ses effets sur la dissociation. À terme, des recommandations méthodologiques sont envisagées. / Scientific background: The alternate bilateral stimulations (ABS) are techniques relating to the visual, tactile or aural modalities used in the psychotherapy EMDR "Eyes Movement Desensitization And reprocessing". Insulating research the SBA often focus on visual modality and relate its effect on subjective disturbance from the decline in observed vegetative activity. However, some PTSD do not exhibit marked vegetative activity, this correlatively with the presence of dissociation (Choi et al., 2017; Sack, Cillien, & Hopper, 2012; Briere, Weathers, & Runtz, 2005) Also, few studies are devoted to auditory ABS except to indicate their lesser effect compared to other modalities (Van Den Hout et al, 2012). On the other hand, the link between the auditory ABS and the dissociation has never been the subject of publication.Problem: What is the effect of auditory ABS on the intensity of event-related dissociation and disturbance signs?Method : After defining dissociation as a process of perception of subjective experience that escapes consciousness, we use an experimental method including 40 voluntary participants to offer an argument in favor of the interest of the auditory ABS in the treatment of dissociation. The study includes 40 healthy participants with stable vegetative activity during the recall of a disturbing memory. The subjects are randomly distributed for the treatment phase during which they recall the event simultaneously to auditory SBA (n = 20) or without hearing SBA (n = 20). The intensity of the signs of dissociation and disturbance is measured in pre-treatment and post-treatment from the average scores in the questionnaire RSDI "Response to script Driven imaging" (Hopper and LA, 2007). Results : For dissociation, there is a significant interaction between the variables group and Moment, F (1, 38) = 5.25, p =. 03. With SBA auditory, there is a difference in pre-and post-treatment scores of significant V = 134, n = 20, p =. 03; In the sense of a decrease. For subjective disturbance, there is no significant interaction between the variables and the difference in scores is not significant.DISCUSSION : The auditory technique reduces the intensity of the dissociation signs. This does not necessarily generate a disturbing subjective experience. These preliminary results open a field of research on dissociative psychopathology and of auditory ABS. Based on the work of Stanislas Dehaene on the "Global Neural work space" and consciousness, we propose a new theoretical model of ABS action by integrating its effects on dissociation. Methodological recommendations are envisaged.
130

Diskret händelsestyrd simulering för att analysera en alternativ vårdväg på glesbygden / Using discrete-event simulation to analyze an alternate route of care in rural areas

Kareld, Oscar, Dannberg, Theresa January 2022 (has links)
Behovet av akut vård har ökat under de senaste åren och satt ökad press på ambulanssektorn i stort. Hur man kan förbättra och effektivisera olika delar av vårdkedjan är en fråga som beslutsfattare inom denna sektor ständigt behöver ha i åtanke för att kunna möta detta behov. Det finns visioner om en likvärdig vård för alla människor i vårt samhälle, som tyvärr kan vara svåra att nå i praktiken. Människor som bor i glesbefolkade områden behöver i regel vänta längre på en ambulans än personer som bor i urbana områden, och transporttiden för dessa ambulansutryckningar blir längre eftersom det ofta är långt till närmaste akutmottagning. För ambulanspersonalen kan det dessutom i vissa fall vara svårt att göra en korrekt bedömning om huruvida en mindre akut patient behöver transporteras till en akutmottagning eller inte. En tänkbar förändring i vårdkedjan kan vara att transportera mindre akuta patienter till en närliggande vårdcentral istället för en akutmottagning - en så kallad alternativ vårdväg. Detta hade både kunnat resultera i kortare transporttider på glesbyggden (vilket i sin tur kan ha en påverkan på ambulansens tillgänglighet) och ge ambulanspersonal möjlighet att välja ett mellansteg mellan att lämna kvar en patient i hemmet och att transportera den till en akutmottagning.  För att undersöka vilken påverkan en alternativ vårdväg kan ha på ambulanser sett till både tid och tillgänglighet, har en diskret händelsestyrd simuleringsmodell utvecklats. Denna modell har använts i en scenariostudie för att undersöka hur en alternativ vårdväg kan påverka ambulans och patienter på glesbygden. Data från SOS Alarm och Region Skåne har möjliggjort en generering av indata som bättre överensstämmer med verkligheten. Resultatet av scenariostudien tyder på att en alternativ vårdväg kan förbättra tillgängligheten för en ambulans på glesbygden genom att förkorta transporttiden till mottagande vårdinstans. / The need for emergency care has increased in recent years and has put increased pressure on the ambulance sector in general. How to improve and streamline different parts of the care chain is an issue that decision-makers in this sector constantly need to keep in mind in order to meet this need. There are visions of equal care for all people in our society, which unfortunately can be difficult to achieve in practice. People who live in sparsely populated areas usually experience longer waiting times to receive an ambulance than people in urban areas, and the transport time for these ambulance calls is longer because of the (usually) longer distance to the nearest emergency room. In addition, for ambulance personnel, it can in some cases be difficult to make a correct assessment of whether a less acute patient needs to be transported to an emergency department. A possible change in the care chain could be to transport less acute patients to a nearby health center instead of an emergency room - a so-called alternate route of care. This could result in both shorter transport times in sparsely populated areas (which in turn can have an impact on the availability of the ambulance) and give ambulance staff the opportunity to choose an intermediate step between leaving a patient at home and transporting it to an emergency department. To investigate the impact that an alternate route of care can have on the aspects of time and accessibility for ambulances, a discrete event-driven simulation model was developed. This model has been used in a scenario study to investigate how an alternate route of care can affect ambulances and patients in sparsely populated areas. Data from SOS Alarm and Region Skåne have made it possible to generate input data that better corresponds to reality. The results of the scenario study indicate that an alternate route of care can improve the accessibility of an ambulance in sparsely populated areas by shortening the transport times to the receiving care institution.

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