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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.
281

Managing upstream supply chain in order to decrease inventory level : A case study on the paper merchant Papyrus Sweden

Krieger, Sören, Bellina, Jérémy, Bodins, Olegs, Olivier, Mathilde January 2013 (has links)
Business Administration, Business Process and Supply Chain Management Degree Project (master), 15 higher education points, 4FE06E, Spring 2013 Authors: Jeremy Bellina, Olegs Bodins, Soeren Krieger and Mathilde Olivier Tutor: Roger Stokkedal Title: Managing Upstream Supply Chain in Order to Decrease Inventory Level: A Case Study on the Paper Merchant Papyrus Sweden. Background: The research is based on Papyrus Sweden, a paper merchant, which is facing a decrease in the demand of paper products. It was identified that inventory level reduction is now crucial for the company in order to stay in the market. Therefore, Papyrus Sweden is focused on inventory level and tied-up capital reduction in order to decrease costs and increase net profit. Purpose: This thesis aims to analyze the current situation in Papyrus Sweden in terms of inventory level and activities related to suppliers, and prepare recommendations which could help Papyrus Sweden to reduce its inventory level. Method: The data has been collected through interviews with managers from the supply chain department as well as through a data sample from Papyrus Sweden database given to the researchers. All data was analyzed and compared with the literature review. Data received from the database was processed and transformed in Microsoft Excel in order to make the analysis. Results: The analysis identifies issues in material planning methods, safety stock calculation, ABC-XYZ classification and forecast calculation, on which Papyrus Sweden could act in order to decrease its inventory level. Furthermore, the researchers identify two solutions Papyrus Sweden could implement with its suppliers in order to reduce inventory level which are a Service Level Agreement and a Vendor Managed Inventory system. Keywords: inventory level, material planning method, safety stock, ABC-XYZ classification, forecast calculation, replenishment lead time, supplier relationship, information sharing, Service Level Agreement (SLA), Vendor Managed Inventory (VMI) and Collaborative planning, forecast and replenishment system (CPFR).
282

Étude de la dynamique des interactions des constituants du complexe de biosynthèse et d’insertion de la sélénocystéine dans la traduction des sélénoprotéines in vivo

Pageau-Crevier, Etienne 07 1900 (has links)
Les sélénoprotéines sont des protéines auxquelles des sélénocystéines, soit le 21e acide aminé, sont incorporées durant leur traduction. Plus précisément, la sélénocystéine (Sec) est un dérivé métabolique de la sérine, mais structurellement équivalent à une cystéine dont on a remplacé l'atome de soufre par du sélénium. Elle se distingue des autres acides aminés puisqu’elle possède sa propre synthétase qui sert à convertir la sérine en Sec alors que le résidu est déjà fixé à l’ARNt. La position d’une Sec sur l’ARNm est indiquée par le codon UGA étant habituellement un signal STOP introduisant le concept de recoding. Grâce à une machinerie métabolique spécifique à l'ARNtSec et à la présence d’un SecIS (Selenocystein Insertion Sequence) sur l’ARNm, ce codon permet la présence d'une Sec dans la protéine. Il est connu que la synthèse débute avec l’acétylation de l’ARNt[Ser]Sec par la seryl-ARNt synthétase (SerRS) afin de donner la seryl-ARNt[Ser]Sec. Cette dernière est subséquemment phosphorylée par l’O-phosphoséryl-ARNt[Ser]Sec kinase (PSTK) qui donnera l’O-phosphoséryl-ARNt[Ser]Sec. Par la suite, un complexe de plusieurs protéines et cofacteurs, agissant comme machinerie pour l’incorporation des Sec durant la traduction, s’associe avec l’ARNt[Ser]Sec puis l’ARNm et, finalement, les composantes du ribosome. Parmi ces protéines, SepSecS catalyse l’étape finale de la synthèse des Sec en convertissant le O-phosphoseryl-ARNt[Ser]Sec en selenocysteinyl-ARNt[Ser]Sec utilisant le sélénophosphate comme source de sélénium. Des études récentes montrent que l’association avec SECp43 serait nécessaire pour que SepSecS joue son rôle et soit ségrégée au noyau pour s’associer à la machinerie de biosynthèse des sélénoprotéines, soit le complexe moléculaire qui reconnaît le codon UGA. Parmi les protéines de la machinerie de biosynthèse des sélénoprotéines que nous avons analysées, il y a eEFSec, RPL30, SPS2, SPS1, SBP2 et NSEP1. Nos résultats d’analyse de la dynamique de l’interaction entre les constituants de la machinerie de biosynthèse et d’incorporation des Sec, confirment plusieurs données de la littérature, mais remettent en question le modèle jusqu’à maintenant établi. Une meilleure compréhension de la dynamique des interactions entre ses constituants et la régulation de cette dynamique permet d’émettre des hypothèses quant au rôle de la machinerie de biosynthèse des sélénoprotéines et de l’importance de sa complexité. Nous avons analysé les interactions in vivo dans des cellules HEK293T au moyen de la technique de Protein-Fragment Complementation Assay (PCA) en couplant, par un clonage moléculaire, les gènes de chacune des protéines d’intérêt avec des fragments des gènes de la protéine luciférase (hRluc). Nous avons ainsi réalisé une fusion en N-terminal et en C-terminal des fragments de luciférase pour chacune des protéines d’intérêt. Puis, nous avons analysé la dynamique des interactions avec les composantes de la machinerie de biosynthèse des Sec. D’autres travaux seront essentiels afin de bâtir sur les résultats présentés dans cette recherche. / Selenoproteins are proteins that incorporate selenocysteines, which is called the 21st amino acid, during their translation. Specifically, selenocysteine (Sec) is a metabolic derivate of serine, which is structurally equivalent to Cys except for replacement of sulfur with an atom of selenium in the δ-position. It differs from other amino acids since a unique synthetase converts the serine into Sec while the residue is already attached to the tRNA. The codon for Sec on the mRNA is a UGA codon that is usually a STOP signal, introducing the concept of "recoding". Through a specific metabolic machinery for the tRNASec and the presence of a SecIS (Selenocysteine Insertion Sequence) on the mRNA, this codon allows the incorporation of the Sec into the protein. However, the mechanism of biosynthesis of this amino acid and its incorporation into proteins is not well understood. It is known that the synthesis starts with the acetylation of tRNA[Ser]Sec by seryl-tRNA synthetase (SerRS) to give the seryl-tRNA[Ser]Sec. The latter is subsequently phosphorylated by the O-phosphoseryl-tRNA[Ser]Sec kinase (PSTK) which will generate the O-phosphoseryl-tRNA[Ser]Sec. Subsequently, a large complex of several proteins and cofactors acting as machinery for incorporation of Sec during translation, associates with tRNA[Ser]Sec and the mRNA and finally, the components of the ribosome. Among these proteins, SepSecS catalyzes the final step in the biosynthesis of Sec converting O-phosphoseryl-tRNA[Ser]Sec into selenocysteinyl-tRNA[Ser]Sec using monoselenophosphate as a source of selenium. Recent studies showed that the association with SECp43 would be required for SepSecS to play its role to segregate into the nucleus to be associated with the machinery that recognizes the UGA codon. Among the proteins of the biosynthesis machinery of selenoproteins that we analyzed, there are eEFSec, RPL30, SPS2, SPS1, SBP2 and NSEP1. Results of analysis of the dynamics of the interaction between the components of the Sec biosynthetic machinery confirm some data from the literature, but conflict with the model so far established. A better understanding of the dynamics of interactions between its constituents and the reaction of this process would allow us to make assumptions about the role of the biosynthetic machinery of selenoproteins and the importance of its complexity. We analyzed the dynamics of interaction in vivo in HEK293T cells using a Protein-Fragment Complementation Assay (PCA) based on a humanized Renilla luciferase (hRLuc) by coupling, by molecular cloning, genes encoding each protein of interest with gene encoding fragments of the luciferase protein (hRluc). We have thus achieved an expression of fusion of N-terminal and C-terminal fragments for each luciferase protein of interest. Then, we analyzed the dynamics of the interaction with the components of the Sec biosynthetic machinery. Further work will be essential to build on the results presented in this research.
283

Développement de modèles C. elegans de Sclérose Latérale Amyotrophique

Vaccaro, Alexandra 12 1900 (has links)
Les gènes TDP-43 (TAR DNA Binding Protein 43) et FUS/TLS (Fused in Sarcoma/Translocated in Liposarcoma) sont actuellement à l’étude quant à leurs rôles biologiques dans le développement de diverses neuropathies telles que la Sclérose Latérale Amyotrophique (SLA). Étant donné que TDP-43 et FUS sont conservés au cours de l’évolution, nous avons utilisé l’organisme modèle C. elegans afin d’étudier leurs fonctions biologiques. Dans ce mémoire, nous démontrons que TDP-1 fonctionne dans la voie de signalisation Insuline/IGF pour réguler la longévité et la réponse au stress oxydatif. Nous avons développé des lignées C. elegans transgéniques mutantes TDP-43 et FUS qui présentent certains aspects de la SLA tels que la dégénérescence des motoneurones et la paralysie adulte. La protéotoxicité causée par ces mutations de TDP- 43 et FUS associées à la SLA, induit l’expression de TDP-1. À l’inverse, la délétion de tdp-1 endogène protège contre la protéotoxicité des mutants TDP-43 et FUS chez C. elegans. Ces résultats suggèrent qu’une induction chronique de TDP-1/TDP-43 sauvage propagerait la protéotoxicité liée à la protéine mutante. Nous avons aussi entrepris un criblage moléculaire pilote afin d’isoler des suppresseurs de toxicité neuronale des modèles transgéniques mutants TDP-43 et FUS. Nous avons ainsi identifié le bleu de méthylène et le salubrinal comme suppresseurs potentiels de toxicité liée à TDP-43 et FUS via réduction de la réponse au stress du réticulum endoplasmique (RE). Nos résultats indiquent que l’homéostasie de repliement des protéines dans le RE représente une cible pour le développement de thérapies pour les maladies neurodégénératives. / Two recently discovered causative genes for ALS, TDP-43 (TAR DNA Binding Protein 43) and FUS/TLS (Fused in Sarcoma/Translocated in Liposarcoma) are under further investigation regarding their biological roles in neuropathies such as Amyotrophic Lateral Sclerosis (ALS). Since TDP-43 and FUS are evolutionarily conserved we turned to the model organism C. elegans to learn more about their biological functions. Here we report that TDP-1 functions in the Insulin/IGF pathway to regulate longevity and the oxidative stress response. We have generated mutant TDP-43 and FUS transgenic lines in C. elegans that recapitulate certain aspects of ALS including motor neuron degeneration and adult-onset paralysis. Proteotoxicity caused by ALS- associated mutations in TDP-43 or FUS also induce TDP-1 expression and consistently, deletion of endogenous tdp-1 rescues mutant TDP-43 and FUS proteotoxicity in C. elegans. These results suggest that chronic induction of wild type TDP-1/TDP-43 by proteotoxicity may actively promote neurodegeneration. We also screened for small- molecule suppressors of mutant TDP-43 and FUS neuronal toxicity in transgenic C. elegans and identified methylene blue and salubrinal as potent suppressors of TDP-43 and FUS toxicity in our models through induction of the endoplasmic reticulum (ER) stress response. Our results indicate that protein folding homeostasis in the ER may be an important target for therapeutic development in neurodegenerative diseases.
284

Modélisation de maladies neurodégénératives à l'aide de cellules souches pluripotentes induites humaines

Lemonnier, Thomas 25 September 2012 (has links) (PDF)
La technologie de reprogrammation de cellules somatiques en cellules souches pluripotentes induites (iPS) offre aujourd'hui l'opportunité de modéliser des maladies neurodégénératives et d'étudier des neurones de patients. Nous avons utilisé cette technologie pour générer deux modèles de maladies neurodégénératives : la mucopolysaccharidose de type IIIB (MPSIIIB) et la forme ALS2 de la sclérose latérale amyotrophique (SLA). Dans le modèle MPSIIIB, nous avons montré que les iPS et les neurones de patients présentaient des défauts caractéristiques de la pathologie telle que l'accumulation de vésicules de surcharge. Des altérations de l'appareil de Golgi dans ces cellules ont également été mises en évidence. Une analyse du transcriptome de précurseurs neuraux MPSIIIB a montré des modifications transcriptionnelles touchant notamment des gènes impliqués dans les interactions de la cellule avec la matrice extracellulaire. Ainsi, dans une seconde étude, des altérations de la migration et de l'orientation de cellules de souris mutantes MPSIIIB ou de patients ont été démontrées. Ces altérations pourraient être responsables des perturbations de la neurogénèse et de la neuritogénèse chez les enfants malades. Dans le modèle SLA/ALS2, nous avons montré que les neurones de patients présentaient des défauts incluant une diminution de la surface des endosomes et des anomalies de la croissance neuritique. Alors qu'il n'existait jusqu'alors aucun modèle cellulaire pertinent reproduisant cette maladie, ce modèle permettra à présent d'étudier les processus physiopathologiques impliqués dans la maladie. En conclusion, la génération de cellules iPS permet de modéliser des maladies neurodégénératives et d'étudier les processus physiopathologiques qui sont associés sur des neurones humains en culture. Ces modèles cellulaires pourraient permettre dans un avenir proche de réaliser des criblages de molécules à visée thérapeutique
285

A Comparative Study on Syntactic Transfer in L2 and L3 school-aged English learners in Sweden : The acquisition of the English existential expletive subject

Fuster Sansalvador, Carles January 2014 (has links)
Various studies have indicated during the past decade that language transfer in L3 may not only stem from L1 but from L2 as well, and that it might sometimes even be stronger from L2, depending on certain factors that facilitate or inhibit transfer. This phenomenon of L2 as the main transfer source in L3 has often been referred to as the ”L2 status factor” (Hammarberg, 2001). The L2 status factor hypothesis expects that the priorly acquired language which scores the highest in several transfer factors will adopt the role of ”external supplier language” (Hammarberg, 2001), i.e. it will be the main source of transfer providing L3 with linguistic features. Namely, the factors that have hitherto been proposed to condition transfer are: typology, psychotypology, proficiency, and psychoaffective factors. The aim of this investigation is to compare the transfer that two groups might exhibit with regard to the English existential expletive pronoun (there), in order to account to whether transfer in L3 might be stronger from L2 than from L1 in this syntactic context. One group consists of subjects with different L1s, L2 Swedish and L3 English; the other is formed by L1 Swedish and L2 English speakers. The informants are aged 13-14, speak the L1s and Swedish (nearly) fluently and English at a basic/intermediate level. Basing the study on the L2 status factor hypothesis, and taking several transfer factors into consideration when analyzing the collected written data, the results are discussed both from a general perspective (from aggregate group scores) and from a micro-perspective (by tracing individual differences). The results obtained suggest that transfer in L3 appears to be stronger from L2 than from L1 when evaluating the aggregate group scores, but only in some cases (and not in most) when examining the individuals separately.
286

Perception of English stress by Mandarin Chinese learners of English: An acoustic study

Wang, Qian 09 December 2008 (has links)
Second language learners of English often experience difficulties in English lexical stress perception. This has traditionally been attributed to transfer of prosodic unit or settings from their first language (L1). Similarly, the problem of Chinese learners with English stress perception was assumed to arise from tonal transfer. However, little research has been devoted to the investigation of the phonetic details of second language (L2) stress perception. The present research focuses on the perception of English lexical stress by Chinese learners of English. The purpose of this study is to reveal the use of acoustic cues in stress perception by Chinese learners of English. In the experiment, F0, duration and intensity were manipulated, each with five steps, on three disyllabic nonsense words to result in a total of 375 nonsense tokens. A group of native speakers of English (NE) and a group of Chinese learners of English (CE) participated in the study and judged whether the stress was on the first or second syllable in the test stimuli. The responses of Chinese learners of English in stress judgment were compared against the baseline of native English speakers. The statistical tests of reliance measures and logistic regression models were used in data analysis. Results indicated that, similar to NE participants, performance by CE participants showed systematic variation as a result of the manipulation of the three acoustic cues. However, CEs were different from NEs in their reliance on the three cues. CE had significantly lower duration and intensity reliance scores but significantly higher F0 than NE. In logistic regression analysis, compared to the NE group, F0 contributed most to the CE models, while the contribution of duration and intensity was minimal. It is concluded from this study that while all three cues have significant effects on stress perception for native English speakers, only F0 has a decisive effect on stress judgments by Chinese learners of English. This study reveals that, rather than transfer of tone at the phonological level, there is transfer of reliance on F0 in the acquisition of L2 English stress. It is suggested that the investigation of phonetic details of learners’ problems with L2 stress acquisition is necessary for L2 speech learning theories and also for L2 stress teaching.
287

The relationship between culture, attitude, social networks and quality of life in midlife Australian and Taiwanese men and women

Fu, Shiu Yun January 2006 (has links)
Background of the Study The aims of this study was to specifically investigate the differences in culture, attitude towards life and social networks between Australian and Taiwanese men and women in addition to determining the factors that predict midlife men and women's quality of life in both countries. Because individualism and collectivism are the two most thoroughly researched constructs in inter-cultural and cross-cultural studies we should look at how these construct affects societies. The theme for individualist cultures (such as Western cultures) is autonomy, while the theme for collectivist cultures (such as Asian cultures) is connection. Most literature available on individualism and collectivism note all cultures have different values that influence their society and ultimately a person's individual health outcome. Very little work has been undertaken in this domain in Australia or Taiwan, particularly in the area of midlife transition and from a cultural perspective. Methodology Data was collected from a cross-sectional, supervised self-administered survey using census data and a probability proportional sampling (PPS) strategy on a general population of men and women aged 40-59 years old who live permanently in Brisbane, Australia and Taipei, Taiwan. The study population was divided into 163 Statistical Local Areas (SLAs) in Brisbane, and 449 Local Government Communities (LGCs) in Taipei. Sixty clusters were randomly selected using probability proportional sampling (PPS) to obtain 30 Australian clusters and 30 Taiwanese clusters. In this study, the 30 (areas) by 7(people) method was used with an additional strategy. The variables were measured including: culture (vertical and horizontal individualism and collectivism), attitude towards life (the total score of optimism), social networks (the total score of emotional, informational, affectionate, tangible, and positive social interaction) and quality of life (physical, psychological, social, and environmental health), social demographical factors and religion and spiritualty. The data analysis procedure included descriptive, bivarite and multivariate multiple regressions and classifications and regression trees (CART). A comparison of the linear regression and regression tree results were discussed. All data analysis was performed by SPSS and S-Plus softwares. Results The overall response rate for the study was 84.2% for midlife Australian men and women and 88.4% for midlife Taiwanese men and women this resulted in 278 Australians (45.3% men) and 398 Taiwanese (35.4% men) providing data to be analysed. Findings in this study indicated country of residence has an overwhelming impact on quality of life with significant differences seen between midlife Australian and Taiwanese men and women (F4, 666= 59.31, P< .001). Results suggest midlife Australian men and women have a better quality of life than midlife Taiwanese men and women. In addition, a comparison of the linear regression and regression tree results reveals that two models identified the same major affect variable for different countries of residence: which was attitude towards life in midlife Australians and social networks in midlife Taiwanese. However, regression trees were able to capture important nonlinear effects as well as interactions between cultural attribute variables. This study demonstrated culture significantly involves multiple functions and interacts with attitude towards life, social networks and individual factors to influence a person's quality of life. The interaction of cultural circumstances and the internal and external factors involved, show less comparative attributes and increased equality attributes, defining the need for people to have a good social networks and a healthy positive disposition. Conclusion Because of the ever increasing flexibility of world travel and a global population, people have much more opportunity to interact with many other cultures which would create improvement in learning opportunities and better health management effectiveness for people the world over. This study has addressed and contributed to the assessment of multi-cultural quality of life research and has important implications for all health professions in addition to government departments and organisational policy makers of both countries. And finally, this study has identified that there needs to be a concerted effort to implement major policy shifts in the near future because of the changing fabric of modern societies. At the same time technology and globalisation have advanced rapidly and point to new opportunities within and across countries for more diverse approaches in research and the implementation of policy initiatives to occur. This study has highlighted that opportunities exist to reflect on current policies for Australian and Taiwanese societies to provide enhanced opportunities to care for the growing midlife populations.
288

Σχεδιασμός και ανάπτυξη πλατφόρμας συστήματος για την υποστήριξη μιας σύγχρονης πολυχρηστικής εικονικής αίθουσας διάθεσης και αξιοποίησης υπηρεσιών δικτύου

Κουμούτσος, Γιάννης 16 April 2013 (has links)
Σε αυτή τη διατριβή προτείνεται ένα πρωτότυπο πλαίσιο το οποίο απελευθερώνει τους κινητούς χρήστες από προκαθορισμένα, μακράς διάρκειας συμβόλαια. Ο κύριος στόχος μας ήταν η δημιουργία ενός ενοποιημένου πλαισίου το οποίο θα μπορεί να ενταχθεί στα υπάρχοντα δίκτυα και τεχνολογίες παρέχοντας μια ολοκληρωμένη λύση για την αυτοματοποιημένη απόκτηση υπηρεσιών διαδικτύου. Η παρούσα διατριβή εστιάζει σε δύο σημαντικά θέματα διαδικτύωσης που είναι η αυτοματοποιημένη διαπραγμάτευση και η συνεργασία μεταξύ των παρόχων. Δίνοντας έμφαση στον αυτοματισμό έχει σχεδιαστεί και υλοποιηθεί ένα εξελιγμένο πλαίσιο για την απόκτηση υπηρεσίας που επιτρέπει στους τελικούς χρήστες, ακόμα και σε αυτούς που έχουν ελάχιστες γνώσεις για την λειτουργία του διαδικτύου, να αναζητήσουν προσβάσιμες υπηρεσίες, δίκτυα και παρόχους που βρίσκονται στην γεωγραφική τους θέση και να διεξάγουν αυτοματοποιημένες διαπραγματεύσεις με τους παρόχους. Η διαδικασία διαπραγμάτευσης μπορεί να διεξαχθεί είτε άμεσα με κάθε πάροχο που ανιχνεύεται στην γεωγραφική θέση του χρήστη είτε μέσω ενός μεσολαβητή υπηρεσιών. Ένα εξίσου σημαντικό ζήτημα σχετικά με την παροχή υπηρεσίας στους τελικούς χρήστες είναι η συνεργασία μεταξύ των παρόχων. Με τον όρο πάροχος αναφερόμαστε και στους παρόχους δικτυακής πρόσβασης (Internet Access Providers - IAPs) και στους παρόχους υπηρεσιών διαδικτύου (Internet Service Providers - ISPs). Το προτεινόμενο πλαίσιο διαπραγμάτευσης παρέχει την απαραίτητη υποδομή για την συνεργασία μεταξύ των IAPs και των ISPs ώστε να παρέχουν αυτήν την διαφάνεια στον τελικό χρήστη. Μια πρωτότυπη προσέγγιση για τον προσδιορισμό και την εκτέλεση του πρωτοκόλλου διαπραγμάτευσης σε συνδυασμό με την στρατηγική και τις προτιμήσεις του χρήστη παρουσιάζεται. Ο σχεδιασμός και η λειτουργία του συστήματος διαπραγμάτευσης βασίζεται στον συνδυασμό του πρόσθιου με τον οπίσθια κινούμενο συμπερασματικό λογισμό (forward and backward reasoning). Επιπλέον περιγράφεται μια πρότυπη υλοποίηση του πλαισίου δυναμικής απόκτησης υπηρεσίας πρόσβασης που χρησιμοποιήθηκε για την διενέργεια μετρήσεων, σε πραγματικές συνθήκες, σχετικά με τον χρόνο που απαιτείται για την ολοκλήρωση των διαπραγματεύσεων και την απόκτηση της υπηρεσίας πρόσβασης. Τα αποτελέσματα που παρουσιάζονται και αναλύονται αποδεικνύουν την δυνατότητα εφαρμογής του προτεινόμενου πλαισίου απόκτησης υπηρεσίας και τα πλεονεκτήματα του σε σχέση με υπάρχουσες λύσεις. / In this thesis, a novel framework, which liberates mobile users from predefined, long-term contracts, is presented. This framework enables mobile users to dynamically acquire any kind of Internet Service, irrespectively of their location and the mobile device used. Our main objective was to create a unified framework which will be easily adopted by existing networks and technologies, imposing little or no restrictions, and provide a complete solution, agnostic to networks, technologies or administrative domains. The thesis focuses on two key networking issues, namely the service negotiation and the inter-provider cooperation, towards a fully automated service acquisition process. Emphasizing on automation, we have designed and implemented a sophisticated service acquisition framework which enables mobile users to search for accessible services, networks, providers, etc. located at their current geographical position and conduct automated negotiations with the providers. The negotiation process can be conducted either directly with any provider scanned in the user’s geographical position, or indirectly with a Service Request Broker (SRB). Through this framework, providers are able to receive incoming requests from new clients, without having any predefined contract with them. Another equally important issue towards service delivery to end-users is the cooperation between providers. With the term provider we refer to both Internet Access Providers (IAPs) and Internet Services Providers (ISPs). The proposed Negotiation Framework provides the necessary infrastructure that enables the cooperation of IAPs and ISPs in order to provide this transparency to the end-user. A novel approach for the specification and execution of the negotiation protocol in combination with the negotiation Strategy and users preferences is presented, based on declarative programming and forward and backward reasoning techniques. The flexible communication and negotiation framework that was defined enables automated negotiations between all parties and can be used as basis towards automated service acquisition for mobile users in Future Internet. A prototype implementation of the service acquisition framework that is based on the e-negotiations framework is also presented. Using this prototype we run some evaluation tests measuring the time needed for different service acquisition scenarios. The results prove the applicability of the framework as compared with similar approaches.
289

Le kaléidoscope de la liaison en français : étude comparée de son appropriation par des apprenants adultes de FLE et des enfants natifs / The kaleidoscope of liaison in French : comparative study of its acquisition by FFL adult learners and by native children

Harnois-Delpiano, Mylene 07 April 2016 (has links)
La liaison en français consiste en l’apparition d’une consonne de liaison entre deux mots dans des contextes précis de la chaîne parlée qui sont divisés en trois catégories : les contextes où la liaison est catégorique (un /n/ enfant), ceux où elle est variable (un gros /z/ avion) et ceux où elle est erratique (une chanson // anglaise). L’objectif de cette recherche est double : dans la première partie, nous exposons une analyse de chaque dimension linguistique et sociolinguistique impliquée dans le phénomène de la liaison. Chacune d’entre elles permet d’éclairer les études qui ont été réalisées ces dernières années auprès d’apprenants de FLE de niveau intermédiaire à avancé, afin de découvrir dans quelle mesure ils parviennent à s’approprier la liaison, en perception comme en production. Dans la seconde partie, nous présentons une étude expérimentale de l’appropriation de la liaison en français suivie par 17 apprenants coréens de FLE de niveau A1-A2 du CECRL enregistrés trois fois sur une durée d’un an, ainsi que par 165 enfants francophones natifs de deux à six ans. Comme il est impossible de comparer les deux groupes de participants du fait de conditions environnementales et de compétences cognitives non alignables, nous avons élaboré une méthode innovante d’appariement sur la base de données factuelles. Nos résultats nous permettent non seulement d’étayer le modèle constructionniste de l’acquisition de la liaison L1 (Chevrot, Dugua, & Fayol, 2009; Chevrot, Dugua, Harnois-Delpiano, Siccardi, & Spinelli, 2013) mais aussi d’esquisser le processus d’appropriation de la liaison L2, très influencé par la graphie apprise dès les premiers cours de FLE. Nous concluons par une mise en perspective didactique prenant en compte l’ensemble des prismes de ce kaléidoscope linguistique de la liaison en français car sans une perception claire de chacun d’entre eux, les apprenants de FLE ne peuvent qu’avoir une vision floue du phénomène. / French liaison is the appearance of a liaison consonant between two words in specific contexts within the spoken word chain. These contexts are divided into three categories : those where the liaison is categorical (e.g. “a child” : un /n/ enfant ), those where it is variable (e.g. “a big plane” : un gros /z/ avion) and those where it is forbidden (e.g. “an english song” : une chanson // anglaise ).The aim of this research is twofold. In the first part, we present an analysis of each linguistic and sociolinguistic sub-field involved in the phenomenon of French liaison. Each of them will allow to shed light on studies of the acquisition of French liaison that have been conducted with learners of FFL (intermediate to advanced level) in recent years. In the second part, we present a comparative study of the acquisition of French liaison based on experimental tasks performed by 17 Korean learners of FFL (level A1-A2 of the CEFR) recorded three times over a one-year and by 165 native children aged two to six. As it is impossible to compare the two groups of participants due to environmental conditions and to different cognitive skills, we have developed an innovative matching method based on factual data. On the one hand, this supports the constructionist model of the acquisition of the liaison L1 (Chevrot, Dugua, & Fayol, 2009; Chevrot, Dugua, Harnois-Delpiano, Siccardi, & Spinelli, 2013). On the other hand, this enables us to sketch the acquisition process of the liaison L2, very influenced by the spelling which is learned from the first FFL course. We conclude with a didactic perspective layout taking into account all the prisms of this linguistic kaleidoscope of French liaison because without a clear perception of each one, FFL learners are bound to have a partial and unfocused interpretation of this phenomenon.
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Effects of positive evidence, indirect negative evidence and form-function transparency on second language acquisition : evidence from L2 Chinese and L2 Thai

Prawatmuang, Woramon January 2018 (has links)
This study investigates second language (L2) acquisition of word orders and markers of collectivity in Chinese and Thai. One of the differences between Chinese and Thai is that Chinese nominal phrases appear with a “numeral + classifier + noun” word order while Thai phrases appear as “noun + numeral + classifier”. Another difference is that men, the Chinese collective marker, cannot be used with nouns referring to animals or indefinite nouns, while phûak, the Thai collective marker, can do so. Based on the cross-linguistic differences, an empirical study was conducted to answer whether Thai learners of Chinese and Chinese learners of Thai would be able to acquire target language (TL) structures that are different from those in their native language (L1) and whether they could reject incorrect TL structures. One hundred and forty-four participants were recruited to complete an acceptability judgment task and a self-paced reading task. It is found that both Chinese and Thai learners could perform native-like in their acceptance of TL word orders since early stages of acquisition. However, it took them until an advanced level to be able to completely reject incorrect TL word orders that resembled structures in their L1. Thai learners also faced difficulty rejecting the use of men with animal and indefinite nouns in their L2 Chinese. In contrast, Chinese learners tended to be successful in their acquisition of phûak. The results are interpreted in terms of roles of positive evidence and form-function transparency. In general, L2 learners tend to acquire a TL structure earlier when they can receive positive evidence in TL input and when a form-function connection of the structure is transparent. Nonetheless, these factors do not have an absolute effect on acquisition outcome since some learners may be able to use a probabilistic learning strategy to successfully acquire L2 knowledge even when positive evidence is unavailable.

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