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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.
21

Makespan Minimization in Re-entrant Permutation Flow Shops

Hinze, Richard 29 August 2017 (has links)
Re-entrant permutation flow shop problems occur in practical applications such as wafer manufacturing, paint shops, mold and die processes and textile industry. A re-entrant material flow means that the production jobs need to visit at least one working station multiple times. A comprehensive review gives an overview of the literature on re-entrant scheduling. The influence of missing operations received just little attention so far and splitting the jobs into sublots was not examined in re-entrant permutation flow shops before. The computational complexity of makespan minimization in re-entrant permutation flow shop problems requires heuristic solution approaches for large problem sizes. The problem provides promising structural properties for the application of a variable neighborhood search because of the repeated processing of jobs on several machines. Furthermore the different characteristics of lot streaming and their impact on the makespan of a schedule are examined in this thesis and the heuristic solution methods are adjusted to manage the problem’s extension.
22

Assembly and test operations with multipass requirement in semiconductor manufacturing

Gao, Zhufeng 30 June 2014 (has links)
In semiconductor manufacturing, wafers are grouped into lots and sent to a separate facility for assembly and test (AT) before being shipped to the customer. Up to a dozen operations are required during AT. The facility in which these operations are performed is a reentrant flow shop consisting of several dozen to several hundred machines and up to a thousand specialized tools. Each lot follows a specific route through the facility, perhaps returning to the same machine multiple times. Each step in the route is referred to as a "pass." Lots in work in process (WIP) that have more than a single step remaining in their route are referred to as multi-pass lots. The multi-pass scheduling problem is to determine machine setups, lot assignments and lot sequences to achieve optimal output, as measured by four objectives related to key device shortages, throughput, machine utilization, and makespan, prioritized in this order. The two primary goals of this research are to develop a new formulation for the multipass problem and to design a variety of solution algorithms that can be used for both planning and real-time control. To begin, the basic AT model considering only single-pass scheduling and the previously developed greedy randomized adaptive search procedure (GRASP) along with its extensions are introduced. Then two alternative schemes are proposed to solve the multipass scheduling problem. In the final phase of this research, an efficient procedure is presented for prioritizing machine changeovers in an AT facility on a periodic basis that provides real-time support. In daily planning, target machine-tooling combinations are derived based on work in process, due dates, and backlogs. As machines finish their current lots, they need to be reconfigured to match their targets. The proposed algorithm is designed to run in real time. / text
23

Oven Usage Optimization : A study on scheduling at the wear edge production at Olofsfors AB / Optimering av ugnsanvändning : En studie av slitstålproduktionen hos Olofsfors AB

Karlsson, Anna January 2023 (has links)
Olofsfors is a steel product manufacturer in Nordmaling, Sweden, producing steel edges for snowplows, tracks for forest machines, and wear edges for buckets on heavy equipment. Most of their products are heated to 900◦ C and then cooled down in water, so-called quenching, during the hardening process. A group of ovens and quench machines together form an oven system and this is used for the hardening. Since it takes a long time for the ovens to reach operating temperature, they are always kept on, which is why it is important to utilize them as effectively as possible. This project investigates the potential utilization increase of one of the three oven systems in the wear edge production unit. This oven system is part of a production line that consists of a saw and a mill, and can process products up to two meters in length, and is hereon called the two-meter line. The two-meter line has a natural inflow through the saw, but raw material produced in other parts of the factory can also be fetched from another inlet. The use of the other inlet is limited by the operator of the two-meter line who has to fetch the material with a forklift. This could be automated so that the operator would not have to handle this inlet. The purpose is to investigate the potential increases in utilization of the oven system for different degrees of automation in order to make the most of the machines and the operator at the two-meter line. In the end, a recommendation is given with a set of ideal properties of the investment that could improve productivity the most. The main method applied in order to explore the potential use of the oven system is a re-entrant flow shop scheduling model. As preceding steps, the production line is first mapped in order to find potential routes for different product families, then the order quantities in the production data are translated into jobs to be scheduled with the help of packing problems and batching rules. The scheduling model of the production line is then solved heuristically with a genetic algorithm based on the sequence of jobs entering the production line followed by a method for creating a deterministic schedule based on this initial sequence of jobs. Lastly, a sensitivity analysis is applied to the processing time for the steps performed by the operator to evaluate the results' robustness. The conclusion is that there is a substantial potential to increase the utilization of the oven system of the two-meter line. The largest potential is when the operator is not actively working at the production line; a maximum of 15.6 h on average. There does also exist a potential to increase utilization while the operator is working at the production line; a maximum of 3.9 h on average. The automation degree needed is high in both cases but due to different reasons. When the operator is not working, the automatic solution needs to work without supervision for longer periods of time, while, in the other case, it needs to be smart enough to adjust to not disturb the operator’s work. For the future, the recommendation is to focus the next step on finding investment options that could exploit the time when the operator is not working. By further specifying the potential investment alternatives, the cost factor can be added to the analysis as well. / Olofsfors AB är en stålproduktstillverkare i Nordmaling, Sverige, som producerar vägstål till bland annat snöplogar, band till skogsmaskiner och slitstål till entreprenadmaskiner. De flesta av deras produkter hettas upp till 900 C och släcks sedan i vatten under härdningsprocessen. En grupp av ugnar och härdmaskiner kallas tillsammans för ett ungsystem och det används till härdningen. Eftersom det tar lång tid att värma upp ugnarna står de alltid på-slagna och det är därför viktigt att använda dem så effektivt som möjligt.  I detta projekt har potentialen att öka användandet av ett av tre ugnsystem i slitstålsproduktionen undersökts.  Ugnsystemet i fråga är en del av en produktionslinje som också består av en såg och en fräs och kan härda artiklar med längder upp till två meter och kallas därför här tvåmeterslinjen. Den naturliga ingången för råmaterial i produktionslinjen är genom sågen, men det finns även en alternativ ingång för råmaterial som förbehandlats i tidigare produktionssteg i fabriken. Användandet av den andra ingången till produktionlinjen begränsas av att operatören i produktionslinjen måste hämta materialet med truck. Detta in-flöde skulle gå att automatisera så att operatören inte skulle behöva hämta dessa artiklar.  Syftet är att undersöka det potentiella ökade nyttjandet av ugnsystemet för olika grader av automation för att bäst använda maskiner och operatör i tvåmeterslinjen. I slutet ges en rekommendation gällande vilka egenskaper investeringen bör ha för att öka produktiviteten mest.  Huvudmetoden för att undersöka möjligt ökat nyttjande av ugnarna är en schemaläggningsmodel. Som underliggande steg kartläggs först produktionslinjen och de olika rutter som olika produktfamiljer tar genom produktionslinjen. Produktkvantiteterna för varje order i produktionsdatan omvandlas sedan till jobb som kan schemaläggas genom packningsproblem och regler för laststorlekar i de olika maskinerna. Schemaläggningsmodellen löses sedan heuristiskt med hjälp av en genetisk algoritm som bestämmer den initiala sekvensen av jobben i första steget, tillsammans med en deterministisk metod för att skapa ett helt schema baserat på den initiala sekvensen av jobben. Slutligen genomförs en känslighetsanalys på processtiderna för steg som motsvarar operatören för att undersöka hur robust resultatet är.    Slutsatsen är att det finns en stor potential att öka nyttjandet av ugnsystemet i tvåmeterslinjen. Den största potentialen är när operatören inte arbetar aktivt vid produktionslinjen, med ett maximum på ca 15,6 h per dag. Det finns också en möjlighet att utöka nyttjandet av ugnarna under tiden som operatören arbetar aktivt med ordrar och outnyttjad tid då är 3,9 h i genomsnitt. Graden av automation är hög oberoende av vilken tid som ska utnyttjas men på grund av olika anledning. Om tiden då operatören inte aktivt jobbar utnyttjas, måste den automatiserade lösningen fungera autonomt under längre tid. Om den istället förväntas fungera parallellt med operatören måste den anpassas smart så att den inte stör operatörens arbete och flöde. Rekommendationen är att fokusera på att hitta konkreta investeringsalternativ som utnyttjar tiden då operatören inte aktivt arbetar för att få bättre kostnadsunderlag att ha med i den vidare analysen.
24

L’incidence d’un dispositif de soutien en gestion de classe sur les pratiques disciplinaires et le sentiment d’efficacité d’enseignants débutants

Dufour, France 10 1900 (has links)
Résumé Cette étude quasi expérimentale consistait à élaborer et à mettre à l’essai une mesure de soutien à l’intention d’enseignants débutants ainsi qu’à évaluer l’efficacité de celle-ci. L’une des particularités de cette mesure, appelée Dispositif de soutien en gestion de classe, était qu’elle était centrée essentiellement sur le développement de la compétence à gérer la classe. L’application du dispositif, échelonnée sur une année scolaire, portait sur une trentaine d’enseignants débutants œuvrant au primaire, en milieu défavorisé, à Montréal. Basé sur les trois phases du modèle théorique d’Archambault et Chouinard (2003), le dispositif se déclinait selon trois cycles de formation : l’établissement du fonctionnement de la classe, le maintien de celui-ci et le soutien à la motivation scolaire, ainsi que l’intervention pour résoudre des problèmes de comportement. Chaque cycle commençait par une journée de formation et d’appropriation (JFA) durant laquelle il y avait présentation d’un contenu théorique puis des ateliers d’appropriation. Par la suite, les enseignants effectuaient des mises en pratique dans leur classe. Pour terminer le cycle, un autre type de rencontre, la rencontre de suivi (RS), servait entre autres à objectiver la pratique. L’aspect original de cette mesure de soutien était que la première rencontre de formation était offerte une semaine avant la rentrée scolaire. Sur le thème « Commencer l’année du bon pied en gestion de classe », cette journée avait pour objectif de soutenir les enseignants débutants dans l’installation du fonctionnement de leur classe. L’efficacité du dispositif a été évaluée sur la base de trois dimensions : l’établissement et le maintien de l’ordre et de la discipline, le sentiment d’efficacité personnelle ainsi que la motivation professionnelle. Les perceptions du groupe d’enseignants débutants ayant pris part aux activités du dispositif (n = 27) ont été comparées à celles d’un groupe témoin (n = 44). Les participants avaient, en moyenne, 2,9 années d’expérience et leur âge variait de 23 à 56 ans. Les données ont été recueillies à l’aide d’un questionnaire auto rapporté rempli en deux temps, soit au deuxième et au huitième mois de l’année scolaire. Les scores des enseignants débutants du dispositif ont augmenté dans le temps pour l’ensemble des variables à l’étude. De plus, les analyses de variance à mesures répétées ont révélé que le dispositif a eu une triple incidence positive, attestée par des effets d’interaction. Les enseignants débutants engagés dans la démarche ont connu une augmentation de leur capacité à implanter les règles de classe, de leur sentiment d’efficacité personnelle à gérer les situations d’apprentissage et de leur motivation professionnelle. En effet, alors que, au début de l’étude, ils rapportaient des scores significativement inférieurs à ceux du groupe témoin, à la fin, les scores étaient équivalents. Les résultats ont aussi montré que les participants du groupe expérimental se distinguaient en affichant un meilleur sentiment d’efficacité à faire apprendre leurs élèves. L’étude nous apprend également que le sentiment d’efficacité personnelle à faire face aux problèmes de comportement et la capacité à gérer les comportements se sont renforcés de façon significative dans le temps chez l’ensemble des enseignants débutants. Finalement, aucun changement significatif n’a été détecté pour deux des huit variables à l’étude : le sentiment d’efficacité personnelle à avoir un effet sur le comportement des élèves et l’application des règles de classe. En définitive, ces résultats sont encourageants. Ils montrent l’enrichissement professionnel que les enseignants débutants peuvent retirer lorsqu’ils sont soutenus adéquatement. Nous croyons que la journée de formation portant sur l’installation du fonctionnement de la classe, avant la rentrée scolaire, a joué un rôle central dans les succès vécus par les enseignants débutants participants. C’est pourquoi nous recommandons ce type de formation assorti d’un suivi à long terme, où d’autres composantes entrent en jeu, afin de nourrir le sentiment d’efficacité personnelle et la motivation professionnelle des nouveaux enseignants. / Abstract The purpose of this quasi experimental study was to develop, test and assess the effectiveness of a support measure for new entrant teachers. One of the characteristics of this measure called “Support tool for classroom management” was to focus on the development of classroom management skills. The study extended over one school year and involved about thirty new primary school teachers in a disadvantaged neighborhood in Montreal. Based on Archambault and Chouinard’s three-phase theoretical model (2003), the tool consisted of three training cycles: develop classroom dynamics, maintain and support academic focus, and act to solve behavior problems. Each cycle began with a training session during which theoretical content was presented, and then followed by hands-on sessions. Afterwards, teachers practiced implementation in their classroom. To complete the cycle, another type of meeting called the “follow-up” meeting was scheduled to, among other things, objectify the practice. The original aspect of this support measure was to provide the first training session one week before the start of the school year. The objective of this first session, themed “Getting off to a good start in classroom management”, was to support new entrant teachers in establishing classroom dynamics. To determine the tool’s effectiveness, we based our assessment on the following three dimensions: development and maintenance of order and discipline, self-efficacy and career motivation. The perceptions of a group of new entrant teachers who participated in tool-related activities (n = 27) were compared with the ones of teachers in a control group (n = 44). Globally, participants had on average 2.9 years of experience and were between 23 and 56 years of age. The data were collected using a self-reported questionnaire that was administered in two stages, in the second and eighth months of the school year. New entrant teachers reported improvements on all study variables. In addition, repeated measures analyses of variance revealed that the tool had had a triple positive impact, as was demonstrated by interaction effects. New entrant teachers who used the tool increased their ability to enforce classroom rules, their self-efficacy at managing learning situations, and their motivation on the job. While they reported significantly lower results at the beginning of the study, the results of the treatment and control groups had become equivalent at the end. The results also indicated that treatment group participants had gained confidence in their teaching skills. The study also revealed that the sense of personal effectiveness at managing behavior problems and the capacity to manage behaviors were significantly reinforced over time amongst all new entrant teachers. Finally, two out the eight study variables did not have a significant effect: sense of personal effectiveness at making an impact on student behavior, and classroom rules enforcement. Ultimately, these results are encouraging. They demonstrate that new entrant teachers can benefit from professional enrichment when they are adequately supported. We believe that the training session on classroom dynamics that took place a week before the start of the school year played a central role in the success of the new entrant teachers who participated in the study. Therefore, we recommend this type of training, along with long-term monitoring, to increase the self-efficacy of new entrant teachers, and, ultimately, to enhance their career motivation.
25

Critical Behavior On Approaching A Double Critical Point In A Complex Mixture

Pradeep, U K 12 1900 (has links)
This thesis reports the results of light-scattering measurements and visual investigations of critical phenomena in the complex mixture 1-propanol (1P) + water (W) + potassium chloride (KCl) which has a special critical point (or a special thermodynamic state) known as the double critical point (DCP). The main theme of the thesis is the critical behavior on approaching a special critical point (i.e., the DCP) in a complex or associating mixture in contrast with that in simple, nonassociating mixtures. The asymptotic critical behavior in complex or associating fluids, such as polymer solutions and blends, ionic and nonionic micellar solutions, microemulsions, aqueous and nonaqueous electrolyte solutions, protein solutions, etc., is now commonly accepted to belong to the 3D-Ising universality class. However, the temperature range of the asymptotic regime in these fluids, with universal behavior, has a nonuniversal width and is, in general, smaller than that in simple or nonassociating fluids. In complex mixtures, which are made up of relatively large molecules or particle clusters of mesoscopic range, the coupling between the conventional correlation length of the critical fluctuations ( ξ) and an additional length scale associated with the mesoscale structures (ξD) is known to modify the approach towards the universal nonclassical critical behavior near their critical points. Nevertheless, the generality of this approach needs to be confirmed. There are also instances of a pure classical or close to classical behavior being observed in the critical domain of complex mixtures, although recent experimental results contradict the earlier observations. Therefore, further experimental evidences than that presently available are necessary before one can say how far the analogy between simple and complex fluids can be pushed. Variations in the effective dielectric constant of a mixture have been known to affect the critical behavior. Furthermore, we anticipate the presence of special critical points in complex mixtures to cause nontrivial modifications in the approach towards the universal asymptotic critical behavior. Special thermodynamic states are characterized by critical fluctuations with exceptionally large correlation length, and are displayed by multicomponent liquid mixtures, in which there are a multitude of thermodynamic paths by which a critical point can be approached, and offers rich information about the critical phenomena. These issues are being addressed in this research work. This thesis is organized into 7 Chapters. Chapter 1 begins with an account of the historical development of the field of critical point phenomena with a brief introduction to critical phenomena in simple fluids. Critical phenomena observed in various complex systems such as aqueous and nonaqueous ionic fluids, polymer solutions and blends, micellar and microemulsion systems, etc., are discussed, with particular attention to investigations into crossover from Ising to mean-field critical behavior observed in these systems, which are relevant to the present work. Theoretical attempts at modeling ionic criticality are cited and summarized. This is followed by a discussion of re-entrant phase transitions in multicomponent liquid systems. An account of the various types of special critical points, such as double critical point, critical double point, critical inflection point, quadruple critical point, etc., highlighting the critical behavior on approaching these special critical points, and some of the models of reentrant miscibility are briefly given. The Chapter ends with a statement on the goals of the present research work. Chapter 2 describes the instrumentation developed and the data acquisition procedures adopted for the study. Details of the thermostats and precision temperature controllers used for visual and light-scattering measurements are provided. The important design considerations relating to the achievement of a high degree of temperature stability (~ ±1 mK in the range 293-383 K) are elucidated clearly. The temperature sensors used in the present experiments and their calibration procedures are discussed. The light-scattering instrumentation is discussed in depth. The problems associated with the light-scattering techniques when it is used to study critical point phenomena, and the strategies adopted to overcome them are discussed. The sample cells used for visual investigations and light- scattering experiments, along with the procedure adopted for cleaning and filling of sample cells are also described. Chapter 3 essentially deals with the characterization of the system 1P + W + KCl. It begins with a brief introduction to the critical behavior in complex mixtures, and the motivation behind choosing the present system. The phase behavior in the present mixture, the generation of the coexistence curves and the line of critical points in the mixture, and the method used for preparation of the samples are described. The criticality of the samples is judged by the equal volume phase separation criterion through visual investigations. Addition of a small amount of salt (i.e., KCl) to the 1P + W solution induces phase separation in the mixture as a result of a salting-out process. Decreasing the salt concentration has the same effect as that of increasing pressure on the liquid-liquid demixing of this mixture. Therefore, KCl may be considered as an appropriate field variable analogous to pressure in this mixture. The mixture 1P + W + KCl exhibits reentrant phase transitions and has an array of lower (TL) and upper (TU) critical solution temperatures. It is found that the line of TL’s and TU’s, known as the line of critical points, merge (TU - TL = ΔT → 0) to form a special thermodynamic state known as the DCP. The DCP is approached as close as 509 mK (i.e., ΔT ~ 509 mK) in this work. An analysis of the critical line shows that it is roughly parabolic in shape, which is in consonance with the predictions of the lattice models and the Landau-Ginzburg theory of phase transition. In addition to the presence of a special critical point, various structure probing techniques like small angle X-ray scattering (SAXS), small angle neutron scattering (SANS), etc., indicate the presence of large-scale density inhomogeneities or clusters in 1P + W solution and its augmentation on adding small amount of KCl. Therefore, the present mixture provides a unique possibility to investigate the combined effects of molecular structuring as well as a special critical point on the critical behavior. Only a section of the coexistence surface of the mixture could be generated, owing to various experimental limitations and other problems inherent to the system. This limited further studies on the coexistence curves in the mixture. Chapter 4 reports the critical behavior of osmotic susceptibility in the present mixture. The behavior of the susceptibility exponent is deduced from static light-scattering measurements, on approaching the lower critical solution temperatures (TL’s) along different experimental paths by varying t [ =| (T - T TL)/ TL|] from the lower one-phase region. The light-scattering data analysis emphasizes the need for correction-to-scaling terms for a proper description of the data over the investigated t range. Renormalization of the critical exponents is observed as the critical line is approached along certain special paths. Experimental evidence for the doubling of the extended scaling exponent Δ1 near the DCP is shown. There is no signature of Fisher renormalization in the values of the critical exponents. The data analysis yields very large magnitudes for the correction amplitudes A1 and A2, with the first-correction amplitude A1 being negative, signifying a nonmonotonic crossover behavior of the susceptibility exponent in the mixture. The magnitudes of the correction amplitudes are observed to increase gradually as TL approaches the DCP. The increasing need for extended scaling in the neighborhood of special critical points has been noted earlier in several aqueous electrolyte solutions, in polymer-solvent systems, etc. However, the magnitudes of the correction amplitudes were not as large as that in the present case. Analysis of the effective susceptibility exponent γeff in terms of t indicate that, for the TL far away from the DCP, γeff displays a nonmonotonic crossover from its single limit 3D Ising value (~ 1.24) towards its mean-field value with increase in t. While for that closest to the DCP, γeff displays a sharp, nonmonotonic crossover from its nearly doubled 3D-Ising value (~ 2.39) towards its nearly doubled mean-field value (~ 1.84) with increase in t. For the in-between TL’s, the limiting value of γeff in the asymptotic as well as nonasymptotic regimes gradually increases towards the DCP. The renormalized Ising regime extends over a relatively larger t range for the TL closest to the DCP, and a trend towards shrinkage in the renormalized Ising regime is observed as TL shifts away from the DCP. Nevertheless, the crossover behavior to the mean-field limit extends well beyond t > 10¯2 for the TL’s studied. The crossover behavior is discussed in terms of the emergence of a new lengthscale ξD associated with the enhanced ion-induced clustering seen in the mixture, as revealed by various structure probing techniques, while the observed unique trend in the crossover is discussed in terms of the varying influence of the DCP on the critical behavior along the TL line. The discussion is extended to explain the observed critical behavior in various re-entrant systems having other special critical points. The extended renormalized Ising regime towards the DCP is also reflected in a decrease in the correlation length amplitude (ξ0) as TL approaches the DCP. It is observed that the first-correction amplitude A1 corresponding to fit using two correction terms becomes more negative as TL approaches the DCP, implying an increase in the value of the parameter ū of the crossover model [by Anisimov et al., Phys. Rev. Lett. 75, 3146 (1995)] as the DCP is approached. This increase in reflected in a trend towards a relatively sharp crossover behavior of γeff as TL shifts towards the DCP, i.e., towards the high temperature critical points. The significance of the field variable tUL in understanding different aspects of reentrant phase transitions is manifested in the present system as well. Analysis of the data in terms of tUL led to the retrieval of universal values of the exponents for all TL’s. The effective susceptibility exponent as a function of tUL displays a nonmonotonic crossover from its asymptotic 3D-Ising value towards a value slightly lower than its nonasymptotic mean-field value of 1. The limited (TL _ T) range restricted such a behavior of the effective exponent (in terms of t as well as tUL) for the lowest TL. This feature of the effective susceptibility exponent is interpreted in terms of the possibility of a nonmonotonic crossover to the mean-field value from lower values in the nonasymptotic, high tUL region, as foreseen earlier in micellar systems. The effective susceptibility exponent in terms of tUL also indicates an increase in the sharpness of crossover towards the high temperature TL’s. An increase in the sharpness of crossover with polymer chain length has been observed in polymer solutions. Therefore, our results suggest the need for further composition and temperature-dependent study of molecular structuring in the present mixture. There is also a large decrease in the dielectric constant of the mixture towards the high temperature TL’s. In Chapter 5 the light-scattering measurements are performed on approaching the DCP along the line of the upper critical solution temperatures (i.e., TU’s), by varying t [ = (T - TU )/ TU ] from the high temperature one-phase region in the mixture. A trend towards shrinkage in the simple scaling region is observed as TU shifts away from the DCP. Such a trend was not visible in the data analysis of the TL’s using the correction terms, due to the varying (TL - T) ranges. The light-scattering data analysis substantiates the existence of a nonmonotonic crossover behavior of the susceptibility exponent in the mixture. As with the TL’s, for the TU closest to the DCP, γeff displays a nonmonotonic crossover from its 3D-Ising value towards its nearly doubled mean-field value with increase in t. While for that far away from the DCP, γeff displays a nonmonotonic crossover from its single limit Ising value towards a value slightly lower than its mean-field value of 1 with increase in t. The limited (TL – T) range restricted such a behavior of γeff for the TL far away from the DCP, This feature of γeff in the nonasymptotic, high t region is yet again interpreted in terms of the possibility of a nonmonotonic crossover to the mean-field value from below. Unlike TL’s, the crossover behavior in the present case is pronounced and more sharp for all TU’s. However, the variation in the width of the renormalized Ising regime on approaching the DCP along the TU line is quite similar to that observed along the TL line. The crossover behavior is attributed to the strong ion-induced structuring seen in the mixture, while the observed trend in the crossover as TU shifts towards/away from the DCP is attributed to the varying influence of the DCP. The influence of the DCP on the critical behavior along the TU (or TL) line decreases as TU (or TL) shifts away from the DCP. Our observations indicate an increase in the sharpness of crossover as the critical temperature shifts from TL towards TU, or in other words, as the critical point shifts towards higher temperatures. SANS measurements on the present mixture indicate no difference in the growth of mesoscale clusters in the lower and upper one-phase regions in the mixture. Hence, the observed increase in the sharpness of crossover towards the TU’s is very puzzling. The dielectric constant of the major constituent (i.e., water, ~ 62 %) of the present mixture decreases from around 80 to 63 as the critical temperature shifts from TL towards TU. Therefore, our results suggest the need to look at the crossover phenomena probably from two perspectives, namely, the solvent or dielectric effect and the clustering effect. The increase in the sharpness of the crossover behavior on approaching the high temperature critical points is probably related to the macroscopic property of the mixture, i.e., to the decrease in the dielectric constant of the mixture, while the actual nonmonotonic character of the crossover behavior is related to the microscopic property of the mixture, i.e., to the clustering effects, the extent of which determines the width of the asymptotic critical domain. However, this conclusion is somewhat subtle and calls for rigorous theoretical and experimental efforts to unravel the exact dependence of the crossover behavior on the dielectric constant. Analysis using the field variable tUL in lieu of the conventional variable t led to the retrieval of unique, universal exponents for all TU’s irrespective of the ΔT value. For all TU’s, the effective susceptibility exponent in terms of tUL displays a nonmonotonic crossover from its asymptotic 3D-Ising value towards a value slightly lower than its nonasymptotic mean-field value of 1, as that observed in the t analysis of the effective exponent for the TU far away from the DCP. Like with the TL’s, the crossover behavior extends over nearly the same tUL range for the TU’s studied. However, the crossover is again sharper when compared to the TL’s. Chapter 6 reports light-scattering measurements (by heating as well as cooling) on a non phase-separating 1P + W + KCl mixture in the vicinity of the DCP. The results indicate that despite the lack of phase-separation or critical points, critical-phenomena-like fluctuations can still occur in homogeneous mixtures if they reside in some other direction than temperature or composition (like, pressure or salt concentration) of the phase diagram. Unlike earlier studies on non phase-separating mixtures, our results indicate a crossover behavior of the effective susceptibility exponent, in addition to the power-law behavior. Chapter 7 sums up the major findings of the work reported in this thesis. It also presents a range of open problems that need to be explored further in order to fully understand the results that are reported in this thesis, especially, regarding the exact dependence of dielectric constant of the mixture on the character of the crossover behavior.
26

L’incidence d’un dispositif de soutien en gestion de classe sur les pratiques disciplinaires et le sentiment d’efficacité d’enseignants débutants

Dufour, France 10 1900 (has links)
Résumé Cette étude quasi expérimentale consistait à élaborer et à mettre à l’essai une mesure de soutien à l’intention d’enseignants débutants ainsi qu’à évaluer l’efficacité de celle-ci. L’une des particularités de cette mesure, appelée Dispositif de soutien en gestion de classe, était qu’elle était centrée essentiellement sur le développement de la compétence à gérer la classe. L’application du dispositif, échelonnée sur une année scolaire, portait sur une trentaine d’enseignants débutants œuvrant au primaire, en milieu défavorisé, à Montréal. Basé sur les trois phases du modèle théorique d’Archambault et Chouinard (2003), le dispositif se déclinait selon trois cycles de formation : l’établissement du fonctionnement de la classe, le maintien de celui-ci et le soutien à la motivation scolaire, ainsi que l’intervention pour résoudre des problèmes de comportement. Chaque cycle commençait par une journée de formation et d’appropriation (JFA) durant laquelle il y avait présentation d’un contenu théorique puis des ateliers d’appropriation. Par la suite, les enseignants effectuaient des mises en pratique dans leur classe. Pour terminer le cycle, un autre type de rencontre, la rencontre de suivi (RS), servait entre autres à objectiver la pratique. L’aspect original de cette mesure de soutien était que la première rencontre de formation était offerte une semaine avant la rentrée scolaire. Sur le thème « Commencer l’année du bon pied en gestion de classe », cette journée avait pour objectif de soutenir les enseignants débutants dans l’installation du fonctionnement de leur classe. L’efficacité du dispositif a été évaluée sur la base de trois dimensions : l’établissement et le maintien de l’ordre et de la discipline, le sentiment d’efficacité personnelle ainsi que la motivation professionnelle. Les perceptions du groupe d’enseignants débutants ayant pris part aux activités du dispositif (n = 27) ont été comparées à celles d’un groupe témoin (n = 44). Les participants avaient, en moyenne, 2,9 années d’expérience et leur âge variait de 23 à 56 ans. Les données ont été recueillies à l’aide d’un questionnaire auto rapporté rempli en deux temps, soit au deuxième et au huitième mois de l’année scolaire. Les scores des enseignants débutants du dispositif ont augmenté dans le temps pour l’ensemble des variables à l’étude. De plus, les analyses de variance à mesures répétées ont révélé que le dispositif a eu une triple incidence positive, attestée par des effets d’interaction. Les enseignants débutants engagés dans la démarche ont connu une augmentation de leur capacité à implanter les règles de classe, de leur sentiment d’efficacité personnelle à gérer les situations d’apprentissage et de leur motivation professionnelle. En effet, alors que, au début de l’étude, ils rapportaient des scores significativement inférieurs à ceux du groupe témoin, à la fin, les scores étaient équivalents. Les résultats ont aussi montré que les participants du groupe expérimental se distinguaient en affichant un meilleur sentiment d’efficacité à faire apprendre leurs élèves. L’étude nous apprend également que le sentiment d’efficacité personnelle à faire face aux problèmes de comportement et la capacité à gérer les comportements se sont renforcés de façon significative dans le temps chez l’ensemble des enseignants débutants. Finalement, aucun changement significatif n’a été détecté pour deux des huit variables à l’étude : le sentiment d’efficacité personnelle à avoir un effet sur le comportement des élèves et l’application des règles de classe. En définitive, ces résultats sont encourageants. Ils montrent l’enrichissement professionnel que les enseignants débutants peuvent retirer lorsqu’ils sont soutenus adéquatement. Nous croyons que la journée de formation portant sur l’installation du fonctionnement de la classe, avant la rentrée scolaire, a joué un rôle central dans les succès vécus par les enseignants débutants participants. C’est pourquoi nous recommandons ce type de formation assorti d’un suivi à long terme, où d’autres composantes entrent en jeu, afin de nourrir le sentiment d’efficacité personnelle et la motivation professionnelle des nouveaux enseignants. / Abstract The purpose of this quasi experimental study was to develop, test and assess the effectiveness of a support measure for new entrant teachers. One of the characteristics of this measure called “Support tool for classroom management” was to focus on the development of classroom management skills. The study extended over one school year and involved about thirty new primary school teachers in a disadvantaged neighborhood in Montreal. Based on Archambault and Chouinard’s three-phase theoretical model (2003), the tool consisted of three training cycles: develop classroom dynamics, maintain and support academic focus, and act to solve behavior problems. Each cycle began with a training session during which theoretical content was presented, and then followed by hands-on sessions. Afterwards, teachers practiced implementation in their classroom. To complete the cycle, another type of meeting called the “follow-up” meeting was scheduled to, among other things, objectify the practice. The original aspect of this support measure was to provide the first training session one week before the start of the school year. The objective of this first session, themed “Getting off to a good start in classroom management”, was to support new entrant teachers in establishing classroom dynamics. To determine the tool’s effectiveness, we based our assessment on the following three dimensions: development and maintenance of order and discipline, self-efficacy and career motivation. The perceptions of a group of new entrant teachers who participated in tool-related activities (n = 27) were compared with the ones of teachers in a control group (n = 44). Globally, participants had on average 2.9 years of experience and were between 23 and 56 years of age. The data were collected using a self-reported questionnaire that was administered in two stages, in the second and eighth months of the school year. New entrant teachers reported improvements on all study variables. In addition, repeated measures analyses of variance revealed that the tool had had a triple positive impact, as was demonstrated by interaction effects. New entrant teachers who used the tool increased their ability to enforce classroom rules, their self-efficacy at managing learning situations, and their motivation on the job. While they reported significantly lower results at the beginning of the study, the results of the treatment and control groups had become equivalent at the end. The results also indicated that treatment group participants had gained confidence in their teaching skills. The study also revealed that the sense of personal effectiveness at managing behavior problems and the capacity to manage behaviors were significantly reinforced over time amongst all new entrant teachers. Finally, two out the eight study variables did not have a significant effect: sense of personal effectiveness at making an impact on student behavior, and classroom rules enforcement. Ultimately, these results are encouraging. They demonstrate that new entrant teachers can benefit from professional enrichment when they are adequately supported. We believe that the training session on classroom dynamics that took place a week before the start of the school year played a central role in the success of the new entrant teachers who participated in the study. Therefore, we recommend this type of training, along with long-term monitoring, to increase the self-efficacy of new entrant teachers, and, ultimately, to enhance their career motivation.
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Повышение качества профессиональной подготовки кадров для предприятий машиностроительной отрасли : магистерская диссертация / Improving the quality of professional training for the engineering industry

Шадрина, А. А., Shadrina, A. A. January 2017 (has links)
Актуальность работы. Работа направлена на решение актуальной проблемы – качественного дефицита квалифицированных кадров машиностроительной отрасли, являющийся одной из причин трудностей, которые в настоящее время испытывает машиностроительное производство в Российской Федерации. Целью исследования является разработка рекомендаций по повышению качества подготовки выпускников технического вуза. Для достижения цели были поставлены следующие задачи: 1. Исследовать уровень базовых знаний студентов, получаемых в школе и проанализировать их взаимосвязь с успеваемостью в вузе; 2. Исследовать психологический портрет студента и проанализировать связь полученных результатов с результатами учебы; 3. Разработать пути воздействия на студента, позволяющие повысить качество его профессиональной подготовки. Объектом исследования являются студенты института новых материалов и технологий и их оценки за сессии. Предмет исследования – успеваемость студентов. Методы исследования: систематизация, психологическое тестирование, обобщение, статистические методы. Публикации. По материалам работы опубликовано 3 статьи (в соавторстве): 1. Современный студент технического вуза: элементы психологического портрета // Педагогическое образование в России. 2016. №4 С.87-92. 2. К вопросу о связи результатов учебы студентов технического вуза с их ответственностью и мотивированностью // Педагогическое образование в России. 2016. №7 С.218-223. 3. О связи обучения физике и математике в общеобразовательной школе с результатами обучения этих дисциплин студентами технического вуза // Педагогическое образование в России. 2016. №10 С.68-71. Работа также представлялась на международный конкурс «Discovery Science: University-2016», где заняла третье место в направлении «Психологические науки». Объем и структура работы. Работа состоит из пояснительной записки объемом 82 страницы и включает в себя введение, три главы, заключение, список использованных источников, состоящий из 47 наименований и 4 приложения. Во введении обоснована актуальность темы, определены цели работы и сформулированы ее задачи. В первой главе анализируется состояние машиностроительного производства в России в настоящее время и описываются факторы, влияющие на его развитие. Во второй главе исследуются причины низкой подготовки кадров для машиностроения. В третьей главе разработана система влияния на студентов с целью повышения качества их обучения. В заключении подведены итоги. Основные выводы 1. В России существует дефицит квалифицированных кадров для машиностроения; 2. Успеваемость студентов оставляет желать лучшего, несмотря на то, что их личностные качества достаточно высоки и не отличаются от качество нашего общества в целом; 3. Предложены методы «нелинейного» воздействия на студентов, основанные на использовании проблемного подхода в обучении, оптимизации речи преподавателя, грамотном оформлении иллюстративного материала, а также рационализации поведения преподавателя в аудитории. / Actuality of work. The work is aimed at solving the actual problem - the shortage of qualified personnel in the machine-building industry. This problem is one of the reasons for the difficulties that machine building in the Russian Federation is currently experiencing. The purpose of the study is to develop recommendations for improving the quality of graduates of a technical university. To achieve the goal, the following tasks were set: 1. To study the level of basic knowledge of students obtained at school and analyze their relationship with academic achievement in the university; 2. To explore the psychological portrait of the student and analyze the relationship between the results obtained and the results of studies; 3. To develop ways of influencing the student, allowing to improve the quality of his professional training. The object of the research is the students of the Institute of New Materials and Technologies and their evaluation for the session. The subject of the study is student performance. Methods of research: systematization, psychological testing, generalization, statistical methods. Publications. Based on the work materials, 3 articles were published (in co-authorship): 1. Modern student of a technical college: elements of a psychological portrait // Pedagogical education in Russia. 2016. №4 С.87-92. 2. On the issue of the relationship of the results of studies of students of a technical college with their responsibility and motivation // Pedagogical Education in Russia. 2016. №7 С.218-223. 3. On the relationship of academic achievement in physics and mathematics in the general education school with the results of teaching these disciplines by students of a technical college // Pedagogical Education in Russia. 2016. №10 С.68-71. The work was also presented at the international competition "Discovery Science: University-2016", where she took the third place in the direction of "Psychological Sciences". Scope and structure of work. The work consists of an explanatory note in the volume of 82 pages and includes an introduction, three chapters, conclusion, a list of sources used, consisting of 47 titles and 4 annexes. In the introduction, the relevance of the topic is substantiated, the goals of the work are defined and its tasks are formulated. In the first chapter, the state of machine-building production in Russia is analyzed at the present time and the factors affecting its development are described. The second chapter explores the reasons for the low training of personnel for machine building. The third chapter developed a system of influence on students in order to improve the quality of their education. In the conclusion the results are summed up. Main conclusions 1. In Russia, there is a shortage of qualified personnel for machine building; 2. The progress of students is poor, despite the fact that their personal qualities are high enough and do not differ from the quality of our society as a whole; 3. Methods of "indirect" impact on students based on the use of a problem approach in teaching, optimizing the speech of the teacher, the competent design of illustrative material, as well as the rationalization of the teacher's behavior in the classroom are suggested.
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Bydrae van 'n program in denkvaardighede tot die wording van beroepstoetreders

Kasselman, Johanna Jacoba 06 1900 (has links)
Text in Afrikaans / It has been said that pupils are not adequately trained to think independently in the current educational system of South Africa. Therefore this research has been undertaken from a psycho-educational perspective to assess the contribution which a programme in cognitive empowerment can make towards the cognitive development and especially the general psychological development of teaching students in their final study year as potential career entrants. From this viewpoint recommendations can be made re the use of this programme in the broader educational context. In this study research has been done from a psycho-educational perspective concerning the cognitive, affective, normative and conative development of the late adolescent and the early career entrant and his/her personality in terms of this career. A group of final year teaching students, who were potential career entrants completed the Programme in Cognitive Empowerment. Before and after the presentation of this programme different media of evaluation were put into use. Based on this research, deductions have been made concerning the contribution which training in the programme has made to the development of the novice teachers. Finally, recommendations have been made concerning the implementing of such a programme. / Daar word beweer dat die onderwysstelsel in Suid-Afrika leerlinge nie toereikend tot selfstandige denke begelei nie. Gevolglik is in hierdie navorsing vanuit sielkundig-opvoedkundige perspektief ondersoek ingestel na die bydrae wat 'n program in kognitiewe versterking maak tot die kognitiewe, en veral die algemene psigiese wording van die finalejaar onderwysstudente - wat potensiele beroepstoetreders is. Hieruit kan dan aanbevelings gemaak word betreffende die gebruik van die program binne bree onderwysverband. In hierdie navorsing is vanuit sielkundig-opvoedkundige perspektief ondersoek ingestel na die kognitiewe, affektiewe, normatiewe en konatiewe wording van die laatadolessente en vroegvolwasse beroepstoetreders en hul persoonlikheid in terme van die beroepswereld. 'n Groep finalejaarstudente, wat potensiele onderwysberoepstoetreders was, het die Program vir Kognitiewe Versterking deurloop. Voor en na die aanbieding van hierdie program is verskillende evalueringsmedia ingeskakel. Uit hierdie ondersoek is gevolgtrekkings gemaak betreffende die bydrae van die program tot die wording van die onderwysberoepstoetreders. Enkele aanbevelings rakende die implementering van so 'n program is ten slotte gemaak. / Psychology of Education / D. Ed. (Sielkundige Opvoedkunde)
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Essays on the drivers of China's international trade / Essais sur les moteurs du commerce international chinois

Fall, Elhadji Moussa Kebe 21 October 2015 (has links)
Dans le premier chapitre, nous avons travaillé sur l’impact d’une réévaluation réelle de la monnaie chinoise sur ses excédents commerciaux. Nous avons suggéré une nouvelle approche pour mesurer cet impact, en utilisant des données de panel relatives aux exportations et aux importations des entreprises à capitaux étrangers et domestiques implantées dans vingt-et-huit provinces chinoises. Nous avons constaté que l’effet d’une réévaluation du Yuan sur les exportations et les importations était plus accentué après l’accession de la Chine à l’OMC. Enfin, d’autres facteurs comme le taux de change nominal et les prix relatifs entrent en jeu dans l’explication de la dynamique des exportations et des importations de la Chine.Dans le deuxième chapitre, nous avons étudié les effets spatiaux sur les exportations et les importations provinciales des entreprises multinationales et domestiques. Nous avons utilisé trois différentes matrices de poids spatiales et maintenu la même division de période qu’au premier chapitre. La méthodologie d’estimation spatiale utilisée a révélé des effets spatiaux importants sur les exportations et les importations des deux types d’entreprises, mais a aussi permis de faire un état des lieux sur l’intégration du marché domestique de la Chine. Dans le troisième chapitre, nous avons étudié les flux de capitaux vers la Chine déguisés en valeur d’échanges commerciaux. Nous avons proposé une nouvelle approche en utilisant les prix des produits échangés les plus susceptibles à la manipulation et étudié leur sensibilité à l’anticipation d’une réévaluation future de la monnaie chinoise. Nous avons trouvé que la balance commerciale de la Chine était surestimée. / In the first chapter, we investigate the impact of a revaluation of the China’s Yuan on its trade balance. We use panel data on export and import of multinational and domestic firms, disaggregated at a regional level in the period 1996-2012.We find significant impact of a revaluation of the Yuan on export and import, the impact differs regionally, time period, and by firms. We also find that other factors like nominal exchange rate and relative prices play significant role in explaining China’s trade balance.In the second chapter, we investigate the spatial effects on China’s trade performance. In fact, we use the same data as in the first essay.We use three different weight matrices to take into account the dynamism in the China’s decentralization policies.We find significant spatial effects on export and import, varying between firms, regions and time period. This essay also reveals important facts on the China’s domestic market integration. In the last chapter, we put forth a new approach to measure capital inflows into China hidden in the regular trade flows. This phenomenon known as trade misinvoicing is suspected to actually overstate China’s trade surpluses.We measure the sensitivity of the prices for some commodities which are the most susceptible to trade misinvoicing to the non-deliverable forward exchange rate for the Yuan in Hong-Kong. We find that, in fact China’s trade balance is relatively overestimated.
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Modelling Submarine Landscape Evolution in Response to Subduction Processes, Northern Hikurangi Margin, New Zealand

Pedley, Katherine Louise January 2010 (has links)
The steep forearc slope along the northern sector of the obliquely convergent Hikurangi subduction zone is characteristic of non-accretionary and tectonically eroding continental margins, with reduced sediment supply in the trench relative to further south, and the presence of seamount relief on the Hikurangi Plateau. These seamounts influence the subduction process and the structurally-driven geomorphic development of the over-riding margin of the Australian Plate frontal wedge. The Poverty Indentation represents an unusual, especially challenging and therefore exciting location to investigate the tectonic and eustatic effects on this sedimentary system because of: (i) the geometry and obliquity of the subducting seamounts; (ii) the influence of multiple repeated seamount impacts; (iii) the effects of structurally-driven over-steeping and associated widespread occurrence of gravitational collapse and mass movements; and (iv) the development of a large canyon system down the axis of the indentation. High quality bathymetric and backscatter images of the Poverty Indentation submarine re-entrant across the northern part of the Hikurangi margin were obtained by scientists from the National Institute of Water and Atmospheric Research (NIWA) (Lewis, 2001) using a SIMRAD EM300 multibeam swath-mapping system, hull-mounted on NIWA’s research vessel Tangaroa. The entire accretionary slope of the re-entrant was mapped, at depths ranging from 100 to 3500 metres. The level of seafloor morphologic resolution is comparable with some of the most detailed Digital Elevation Maps (DEM) onshore. The detailed digital swath images are complemented by the availability of excellent high-quality processed multi-channel seismic reflection data, single channel high-resolution 3.5 kHz seismic reflection data, as well as core samples. Combined, these data support this study of the complex interactions of tectonic deformation with slope sedimentary processes and slope submarine geomorphic evolution at a convergent margin. The origin of the Poverty Indentation, on the inboard trench-slope at the transition from the northern to central sectors of the Hikurangi margin, is attributed to multiple seamount impacts over the last c. 2 Myr period. This has been accompanied by canyon incision, thrust fault propagation into the trench fill, and numerous large-scale gravitational collapse structures with multiple debris flow and avalanche deposits ranging in down-slope length from a few hundred metres to more than 40 km. The indentation is directly offshore of the Waipaoa River which is currently estimated to have a high sediment yield into the marine system. The indentation is recognised as the “Sink” for sediments derived from the Waipaoa River catchment, one of two target river systems chosen for the US National Science Foundation (NSF)-funded MARGINS “Source-to-Sink” initiative. The Poverty Canyon stretches 70 km from the continental shelf edge directly offshore from the Waipaoa to the trench floor, incising into the axis of the indentation. The sediment delivered to the margin from the Waipaoa catchment and elsewhere during sea-level high-stands, including the Holocene, has remained largely trapped in a large depocentre on the Poverty shelf, while during low-stand cycles, sediment bypassed the shelf to develop a prograding clinoform sequence out onto the upper slope. The formation of the indentation and the development of the upper branches of the Poverty Canyon system have led to the progressive removal of a substantial part of this prograding wedge by mass movements and gully incision. Sediment has also accumulated in the head of the Poverty Canyon and episodic mass flows contribute significantly to continued modification of the indentation by driving canyon incision and triggering instability in the adjacent slopes. Prograding clinoforms lying seaward of active faults beneath the shelf, and overlying a buried inactive thrust system beneath the upper slope, reveal a history of deformation accompanied by the creation of accommodation space. There is some more recent activity on shelf faults (i.e. Lachlan Fault) and at the transition into the lower margin, but reduced (~2 %) or no evidence of recent deformation for the majority of the upper to mid-slope. This is in contrast to current activity (approximately 24 to 47% shortening) across the lower slope and frontal wedge regions of the indentation. The middle to lower Poverty Canyon represents a structural transition zone within the indentation coincident with the indentation axis. The lower to mid-slope south of the canyon conforms more closely to a classic accretionary slope deformation style with a series of east-facing thrust-propagated asymmetric anticlines separated by early-stage slope basins. North of the canyon system, sediment starvation and seamount impact has resulted in frontal tectonic erosion associated with the development of an over-steepened lower to mid-slope margin, fault reactivation and structural inversion and over-printing. Evidence points to at least three main seamount subduction events within the Poverty Indentation, each with different margin responses: i) older substantial seamount impact that drove the first-order perturbation in the margin, since approximately ~1-2 Ma ii) subducted seamount(s) now beneath Pantin and Paritu Ridge complexes, initially impacting on the margin approximately ~0.5 Ma, and iii) incipient seamount subduction of the Puke Seamount at the current deformation front. The overall geometry and geomorphology of the wider indentation appears to conform to the geometry accompanying the structure observed in sandbox models after the seamount has passed completely through the deformation front. The main morphological features correlating with sandbox models include: i) the axial re-entrant down which the Poverty Canyon now incises; ii) the re-establishment of an accretionary wedge to the south of the indentation axis, accompanied by out-stepping, deformation front propagation into the trench fill sequence, particularly towards the mouth of the canyon; iii) the linear north margin of the indentation with respect to the more arcuate shape of the southern accretionary wedge; and, iv) the set of faults cutting obliquely across the deformation front near the mouth of the canyon. Many of the observed structural and geomorphic features of the Poverty Indentation also correlate well both with other sediment-rich convergent margins where seamount subduction is prevalent particularly the Nankai and Sumatra margins, and the sediment-starved Costa Rican margin. While submarine canyon systems are certainly present on other convergent margins undergoing seamount subduction there appears to be no other documented shelf to trench extending canyon system developing in the axis of such a re-entrant, as is dominating the Poverty Indentation. Ongoing modification of the Indentation appears to be driven by: i) continued smaller seamount impacts at the deformation front, and currently subducting beneath the mid-lower slope, ii) low and high sea-level stands accompanied by variations on sediment flux from the continental shelf, iii) over-steepening of the deformation front and mass movement, particularly from the shelf edge and upper slope.

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