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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.
391

Literature Study and Assessment of Trajectory Data Mining Tools / Litteraturstudie och utvärdering av verktyg för datautvinning från rörelsebanedata

Kihlström, Petter January 2015 (has links)
With the development of technologies such as Global Navigation Satellite Systems (GNSS), mobile computing, and Information and Communication Technology (ICT) the procedure of sampling positional data has lately been significantly simplified.  This enables the aggregation of large amounts of moving objects data (i.e. trajectories) containing potential information about the moving objects. Within Knowledge Discovery in Databases (KDD), automated processes for realization of this information, called trajectory data mining, have been implemented.   The objectives of this study is to examine 1) how trajectory data mining tasks are defined at an abstract level, 2) what type of information it is possible to extract from trajectory data, 3) what solutions trajectory data mining tools implement for different tasks, 4) how tools uses visualization, and 5) what the limiting aspects of input data are how those limitations are treated. The topic, trajectory data mining, is examined in a literature review, in which a large number of academic papers found trough googling were screened to find relevant information given the above stated objectives.   The literature research found that there are several challenges along the process arriving at profitable knowledge about moving objects. For example, the discrete modelling of movements as polylines is associated with an inherent uncertainty since the location between two sampled positions is unknown.  To reduce this uncertainty and prepare raw data for mining, data often needs to be processed in some way. The nature of pre-processing depends on sampling rate and accuracy properties of raw in-data as well as the requirements formulated by the specific mining method. Also a major challenge is to define relevant knowledge and effective methods for extracting this from the data. Furthermore are conveying results from mining to users an important function. Presenting results in an informative way, both at the level of individual trajectories and sets of trajectories, is a vital but far from trivial task, for which visualization is an effective approach.   Abstractly defined instructions for data mining are formally denoted as tasks. There are four main categories of mining tasks: 1) managing uncertainty, 2) extrapolation, 3) anomaly detection, and 4) pattern detection. The recitation of tasks within this study provides a basis for an assessment of tools used for the execution of these tasks. To arrive at profitable results the dimensions of comparison are selected with the intention to cover the essential parts of the knowledge discovery process. The measures to appraise this are chosen to make results correctly reflect the 1) sophistication, 2) user friendliness, and 3) flexibility of tools. The focus within this thesis is freely available tools, for which the range is proven to be very small and fragmented. The selection of tools found and reported on are: MoveMine 2.0, MinUS, GeT_Move and M-Atlas.   The tools are reviewed entirely through utilizing documentation of the tools. The performance of tools is proved to vary along all dimensional measures except visualization and graphical user interface which all tools provide. Overall the systems preform well considering user-friendliness, somewhat good considering sophistication and poorly considering flexibility. However, since the range of tasks, which tools intend to solve, overall is varying it might not be appropriate to compare the tools in term of better or worse.   This thesis further provides some theoretical insights for users regarding requirements on their knowledge, both concerning the technical aspects of tools and about the nature of the moving objects. Furthermore is the future of trajectory data mining in form of constraints on information extraction as well as requirements for development of tools discussed, where a more robust open source solution is emphasised. Finally, this thesis can altogether be regarded to provide material for guidance in what trajectory mining tools to use depending on application. Work to complement this thesis through comparing the actual performance of tools, when using them, is desirable. / I och med utvecklingen av tekniker så som Global Navigation Satellite systems (GNSS), mobile computing och Information and Communication Technology (ICT) har tillvägagångsätt för insamling av positionsdata drastiskt förenklats. Denna utveckling har möjliggjort för insamlandet av stora mängder data från rörliga objekt (i.e. trajecotries)(sv: rörelsebanor), innehållande potentiell information om dessa rörliga objekt. Inom Knowledge Discovery in Databases (KDD)(sv: kunskapsanskaffning i databaser) tillämpas automatiserade processer för att realisera sådan information, som kallas trajectory data mining (sv: utvinning från rörelsebanedata).   Denna studie ämnar undersöka 1) hur trajectory data mining tasks (sv: utvinning från rörelsebanedata uppgifter) är definierade på en abstrakt nivå, 2) vilken typ av information som är möjlig att utvinna ur rörelsebanedata, 3) vilka lösningar trajectory data ming tools (sv: verktyg för datautvinning från rörelsebanedata) implementerar för olika uppgifter, 4) hur verktyg använder visualisering, och 5) vilka de begränsande aspekterna av input-data är och hur dessa begränsningar hanteras. Ämnet utvinning från rörelsebanedata undersöks genom en litteraturgranskning, i vilken ett stort antal och akademiska rapporter hittade genom googling granskas för att finna relevant information givet de ovan nämnda frågeställningarna.   Litteraturgranskningen visade att processen som leder upp till en användbar kunskap om rörliga objekt innehåller dock flera utmaningar. Till exempel är modelleringen av rörelser som polygontåg associerad med en inbyggd osäkerhet eftersom positionen för objekt mellan två inmätningar är okänd. För att reducera denna osäkerhet och förbereda rådata för extraktion måste ofta datan processeras på något sätt. Karaktären av förprocessering avgörs av insamlingsfrekvens och exakthetsegenskaper hos rå indata tillsammans med de krav som ställs av de specifika datautvinningsmetoderna. En betydande utmaning är också att definiera relevant kunskap och effektiva metoder för att utvinna denna från data. Vidare är förmedlandet av resultat från utvinnande till användare en viktig funktion. Att presentera resultat på ett informativt sätt, både på en nivå av enskilda rörelsebanor men och grupper av rörelsebanor är en vital men långt ifrån trivial uppgift, för vilken visualisering är ett effektivt tillvägagångsätt.   Abstrakt definierade instruktioner för dataextraktion är formellt betecknade som uppgifter. Det finns fyra huvudkategorier av uppgifter: 1) hantering av osäkerhet, 2) extrapolation, 3) anomalidetektion, and 4) mönsterdetektion. Sammanfattningen av uppgifter som ges i denna rapport utgör ett fundament för en utvärdering av verktyg, vilka används för utförandet av uppgifter. För att landa i ett givande resultat har jämförelsegrunderna för verktygen valts med intentionen att täcka de viktigaste delarna av processen för att förvärva kunskap. Måtten för att utvärdera detta valdes för att reflektera 1) sofistikering, 2) användarvänlighet, och 3) flexibiliteten hos verktygen. Fokuset inom denna studie har varit verktyg som är gratis tillgängliga, för vilka utbudet har visat sig vara litet och fragmenterat. Selektionen av verktyg som hittats och utvärderats var: MoveMine 2.0, MinUS, GeT_Move and M-Atlas.   Verktygen utvärderades helt och hållet baserat på tillgänglig dokumentation av verktygen.  Prestationen av verktygen visade sig variera längs alla jämförelsegrunder utom visualisering och grafiskt gränssnitt som alla verktyg tillhandahöll. Överlag presterade systemen väl gällande användarvänlighet, någorlunda bra gällande sofistikering och dåligt gällande flexibilitet. Hursomhelst, eftersom uppgifterna som verktygen avser att lösa varierar är det inte relevant att värdera dem mot varandra gällande denna aspekt.   Detta arbete tillhandahåller vidare några teoretiska insikter för användare gällande krav som ställs på deras kunskap, både gällande de tekniska aspekterna av verktygen och rörliga objekts beskaffenhet. Vidare diskuteras framtiden för utvinning från rörelsebanedata i form av begränsningar på informationsutvinning och krav för utvecklingen av verktyg, där en mer robust open source lösning betonas. Sammantaget kan detta arbete anses tillhandahålla material för vägledning i vad för verktyg för datautvinning från rörelsebanedata som kan användas beroende på användningsområde. Arbete för att komplettera denna rapport genom utvärdering av verktygens prestation utifrån användning av dem är önskvärt.
392

Manligt och kvinnligt i historieläroböcker : En studie av hur tre läroboksförfattare förhåller sig till framställningen av manliga respektive kvinnliga sysslor, platser och egenskaper / Male and female in history textbook : A study of how three history textbook authors approaches the historical representations of male and female tasks, places and traits

Johansson, Filip January 2022 (has links)
The purpose of this study has been to investigate which approach history textbooks authors have towards the historical representations of male respective female tasks, places and traits, aswell as how these representations relates to the gender perspective in Gy 11.In this study three history textbooks are analyzed with the help of a discourse analysis based on a sender-oriented interpretation strategy and Yvonne Hirdman’s gender system. The result shows that all history textbooks authors in general have a critical approach towards the historical aswell as the contemporary representation of male respective female tasks, places and traits and that this is in line with the gender perspective in Gy 11. In the concluding discussion it is established that the result of this study differ from previous studies regarding the presence of dominating male norms, the separation of male and female aswell as the lack of gender perspective.
393

Modelling tasks for learning, teaching, testing and researching

Greefrath, Gilbert 16 April 2012 (has links)
The article deals with a special kind of modelling tass. These problems are used for learning and researching as well. So the results of an empirical study on mathematical modelling of pupils in secondary schools are presented. Pupils of forms 8-10 were observed working on open, realistic problems. These observations were recorded and evaluated. The goal of the presented part of the study is a detailed look at the control processes of modelling problems. In this context changes between real life control and mathematical control during the control phases are studied and evaluated. We describe in detail the sub phases of controlling and explain their connection with modelling process. The problems used in this project can also be used in math lessons, so this kind of research can put teachers and researchers together. These tasks are suitable to support ongoing in-service development and teacher education.
394

Tasks in English workbooks : An analysis of task types in workbooks for the English subject in the ninth grade

Dandache, Rayan January 2021 (has links)
The study aimed to find out and compare what skills and task-types that could be found in two workbooks for the ninth grade in English as a second language in Sweden. The research was conducted using a quantitative content and text analysis in order to compare two workbooks and categorize their tasks into production and interaction skills and task-types. The workbooks were chosen as they were the latest editions at the time. The study showed that both workbooks prioritized production and interaction skills. Both had a low focus on speaking skills but Sparks 9 had more integrated skills in tasks. Wings 9 had a major focus on writing skills and grammar. Both workbooks focused on comparing, problem solving, listing and sorting and ordering task-types. Task-types such as creative tasks and sharing personal experience were low in both workbooks but Sparks 9 had a better overall spread of all task-types in general. The understanding that tasks incorporate much more than simply goals to achieve could potentially be used in a practical teaching environment by adapting tasks to fit students´ different needs.
395

Redovisningsekonomer och digitalisering : En kvalitativ studie om digitaliseringens inverkan på svenska redovisningsekonomers yrkesroll

Rande, Marika, Vejde, Caroline January 2021 (has links)
Den pågående digitaliseringen genomsyrar flera av samhällets olika yrkesområden och där dess inverkan inom redovisningsbranschen är påtaglig. Tidigare forskning menar att de större förändringarna har skett inom det senaste decenniet och efterfrågar därmed fler kvalitativa studier som berör området redovisningsekonomer och hur de uppfattar digitaliseringen i sin yrkesroll. Studien ämnar därmed att undersöka hur digitaliseringen påverkar svenska redovisningsekonomers arbetsmoment och vilken inverkan detta har på yrkesrollen. För att besvara syftet har en kvalitativ metod tillämpats i form av semistrukturerade intervjuer där urvalet bestod av sex redovisningsekonomer verksamma inom mindre redovisningsbyråer och företag. Det teoretiska ramverket som har använts grundar sig på Knudsens (2020) studie och hans fyra beståndsdelar som enligt honom utgör redovisning. Det teoretiska ramverket heter Modified framework for research on accounting. Studiens resultat påvisade att digitaliseringen har bidragit till att arbetsmoment kan utföras mer effektivt som därmed har lett till en förändrad yrkesroll. De traditionella arbetsmomenten går snabbare att utföra så att redovisningsekonomer numera kan ägna mer tid åt kvalificerade arbetsmoment som är mer värdeskapande. Andra faktorer som bidrar till en förändrad yrkesroll är att de upplever en högre efterfrågan av digitala kunskaper från både branschen och kunder. Dessa är bidragande faktorer till att de numera beskriver sin yrkesroll mer som rådgivare alternativt systemvetare. Effektiviseringsmöjligheter är inte ett unikt resultat för denna studie då effektivitet är i likhet med vad många andra forskare redan kommit fram till. Digitaliseringen är en pågående process som öppnar upp för just effektivisering, nya möjligheter och utmaningar samt mål, där redovisningsekonomer måste lära sig att navigera bland dessa. Vårt teoretiska bidrag blir således att det blir svårt att prata om redovisningsekonomen i singular med anledning av att redovisningsekonomer anammar digitaliseringen på olika sätt som därmed får en varierad inverkan på yrkesrollen. För en fortsatt konkurrenskraft i branschen kan redovisningsekonomer dock inte bortse från digitaliseringen. / The ongoing digitalization permeates several occupations within the society, where its impact within the accounting sector is palpable. Earlier research suggests that major changes have taken place in the last decade and are calling for more qualitative studies connected to the role of the accountant and how they perceive digitalization within their profession. The purpose of this study is therefore to investigate how the digitalization affects Swedish accountants’ work tasks and what the role this plays in their occupational role. To answer the purpose, a qualitative method has been applied in the form of semi-structured interviews, where the selection consisted of six accountants, operating in small-sized accounting firms and companies. The theoretical foundational framework is built on Knudsen’s (2020) study and the four keycomponents that, according to him, constitute accounting. The name of the theoretical framework is Modified framework for research on accounting. The result of the study showed that the digitalization has contributed to the fact that tasks can be executed with more efficiency, leading to the change of the role of the accountant. The traditional tasks are quicker to perform so that the accountant can devote more time to more skilled tasks, creating more value in their role. Other factors contributing to a change of the role are that the accountants are experiencing a higher demand for digital literacy, both from the sector and clients alike. These are contributing factors to the fact that they nowadays describe their professional role lean more of business consultants or systems engineers. However, efficiency is not an exceptional result for this study as it is similar to what many other researchers have already concluded. Digitalization is an ongoing process that opens up for efficiency, new opportunities and challenges, and goals, where accounting economists must learn to navigate among these. Our theoretical contribution is the difficulty in terms of talking about the accounting economist in a singular form since accounting economists adopt digitalization in different ways which have a varying impact on the professional role. For continued competitiveness in the industry, accounting economists can thus not ignore digitalization.
396

Suchbasierte Algorithmen für das Scheduling unabhängiger paralleler Tasks

Dietze, Robert 09 May 2022 (has links)
In parallelen Anwendungen, die auf Grundlage des Programmiermodells der gemischten Parallelität implementiert wurden, lassen sich meist unabhängige Programmteile (Tasks) identifizieren, die sowohl parallel zueinander als auch selbst parallel ausgeführt werden können. Zur Reduzierung der Ausführungszeit solcher Anwendungen auf einem parallelen System wird eine zeitliche und räumliche Zuordnung dieser parallelen Tasks zu den Prozessoren benötigt, welche mithilfe von Schedulingverfahren ermittelt werden kann. Jedoch ist bereits das Scheduling voneinander abhängiger Single-Prozessor-Tasks auf ein paralleles System mit zwei Prozessoren NP-schwer, weshalb zur Lösung von Schedulingproblemen häufig List-Scheduling-Heuristiken verwendet werden. Das Scheduling unabhängiger paralleler Tasks ist aufgrund der vielen zusätzlichen Zuordnungsmöglichkeiten deutlich komplexer und erfordert daher dedizierte Lösungsverfahren. Einen vielversprechenden Ansatz zur Lösung komplexer Schedulingprobleme bilden suchbasierte Verfahren, die lokale oder globale Suchstrategien zur Lösungsfindung nutzen. In der vorliegenden Arbeit wird untersucht, inwieweit sich derartige Verfahren für das Scheduling unabhängiger paralleler Tasks auf heterogene Systeme bestehend aus Multicore- Rechnern mit unterschiedlichen Eigenschaften eignen. Zu diesem Zweck werden vier suchbasierte Schedulingverfahren entwickelt und untersucht. Konkret werden zwei modifizierende und zwei inkrementelle Verfahren vorgestellt, die von Suchverfahren wie der A*-Suche und Metaheuristiken wie der Tabu-Suche und des Simulated Annealing inspiriert sind. Zusätzlich wird eine Kostenmodellierung in Form von parametrisierten Laufzeitformeln präsentiert, mit der die Ausführungszeiten der parallelen Tasks auf heterogenen Systemen modelliert werden können. Die Verfahren werden in Laufzeitmessungen auf heterogenen Rechnerplattformen untereinander und mit existierenden List-Scheduling-Heuristiken verglichen. Als Anwendungen für die Messungen werden sowohl Programme der SPLASH-3-Benchmark-Suite als auch eine praxisnahe Simulationsanwendung zur Bauteilbelastung untersucht. Die Ergebnisse zeigen, dass alle vier Verfahren im Vergleich zu existierenden List-Scheduling-Heuristiken eine signifikante Reduktion der Ausführungszeit erreichen können.
397

Språkutvecklande arbetssätt i matematik för flerspråkiga elever - enligt lärare

Klangegård, Sophia, Sjölin, Petra January 2020 (has links)
Today's society is multicultural which means that also our classrooms are multicultural. The teaching must then be designed so that all pupils can develop as far as possible, which is expressed in the curriculum. The purpose of this study is therefore to investigate how Swedish teachers work with language development in the mathematics subject, to support these multilingual students’ knowledge development to the maximum.This study has a qualitative approach as it is based on semi-structured interviews. A total of four teachers participated and were thus able to give their picture of how they work with language development in mathematics. The results of the study indicate a large divergence between the teachers' ways of working, relating to multilingual classrooms, and language development work. In addition, some aspects are more crucial to the development of languages and knowledge for multilingual students. This includes collaborative work where language has a central role in which students get to talk, reason, and communicate mathematics with others. Other key strategies that emerge are reality anchoring, customized tasks, and multilingualism as a resource. The work is analyzed in relation to theories of socio-cultural learning and pragmatism.
398

Exploring mathematical literacy : the relationship between teachers’ knowledge and beliefs and their instructional practices

Botha, Johanna Jacoba 15 February 2012 (has links)
South Africa is the first country in the world to offer Mathematical Literacy as a school subject. This subject was introduced in 2006 as an alternative to Mathematics in the Further Education and Training band. The purpose of this subject is to provide learners with an awareness and understanding of the role that mathematics plays in the modern world, but also with opportunities to engage in real-life problems in different contexts. A problem is the beliefs some people in and outside the classroom have regarding this subject such as teachers believing ML is the dumping ground for mathematics underperformers (Mbekwa, 2007). Another problem is the belief of some principals that any nonmathematics teacher can teach ML. In practice there is Mathematics teachers who teach ML in the same way that they teach Mathematics; non-Mathematics teachers who in many cases lack the necessary mathematical content knowledge and skills to teach ML competently; and Mathematics teachers who adapted their practices to teach ML using different approaches than those required for teaching Mathematics. Limited in-depth research has been done on the ML teachers, what they believe and what knowledge is required to teach this subject effectively and proficiently. The purpose of this study is to investigate the way in which ML is taught in a limited number of classrooms with the view to exploring the relationship between ML teachers’ knowledge and beliefs and their instructional practices. According to Artzt, Armour-Thomas and Curcio (2008) the instructional practice of the teacher plays out in the classroom where teachers’ goals, knowledge and beliefs serve as the driving force behind their instructional efforts to guide and mentor learners in their search for knowledge. To accomplish this aim, an in-depth case study was conducted to explore the nature of teachers’ knowledge and beliefs about ML as manifested in their instructional practices. A qualitative research approach was used in which observations and interviews served as data collection techniques enabling me to interpret the reality as I became part of the lives of the teachers. My study revealed that there is a dynamic but complex relationship between ML teachers’ knowledge and beliefs and their instructional practices. The teachers’ knowledge, but not their stated beliefs were reflected in their instructional practices. Conversely, in one case, the teacher’s instructional practice also had a positive influence on her knowledge and beliefs. It was further revealed that mathematics teacher training and teaching experience played a significant role in the productivity of the teachers’ practices. The findings suggest that although mathematical content knowledge is required to develop PCK, it is teaching experience that plays a crucial role in the development of teachers’ PCK. Although the study’s results cannot be generalised due to the small sample, I believe that the findings concerning the value of teachers’ knowledge and the contradictions between their stated beliefs and practices could possibly contribute to teacher training. Curriculum decision-makers should realise that the teaching of ML requires specially trained, competent, dedicated teachers who value the subject. This exploratory study concludes with recommendations for further research. / Thesis (PhD)--University of Pretoria, 2011. / Science, Mathematics and Technology Education / unrestricted
399

Placement de graphes de tâches de grande taille sur architectures massivement multicoeurs / Mapping of large task network on manycore architecture

Berger, Karl-Eduard 08 December 2015 (has links)
Ce travail de thèse de doctorat est dédié à l'étude d'un problème de placement de tâches dans le domaine de la compilation d'applications pour des architectures massivement parallèles. Ce problème vient en réponse à certains besoins industriels tels que l'économie d'énergie, la demande de performances pour les applications de type flots de données synchrones. Ce problème de placement doit être résolu dans le respect de trois critères: les algorithmes doivent être capable de traiter des applications de tailles variables, ils doivent répondre aux contraintes de capacités des processeurs et prendre en compte la topologie des architectures cibles. Dans cette thèse, les tâches sont organisées en réseaux de communication, modélisés sous forme de graphes. Pour évaluer la qualité des solutions produites par les algorithmes, les placements obtenus sont comparés avec un placement aléatoire. Cette comparaison sert de métrique d'évaluation des placements des différentes méthodes proposées. Afin de résoudre à ce problème, deux algorithmes de placement de réseaux de tâches de grande taille sur des architectures clusterisées de processeurs de type many-coeurs ont été développés. Ils s'appliquent dans des cas où les poids des tâches et des arêtes sont unitaires. Le premier algorithme, nommé Task-wise Placement, place les tâches une par une en se servant d'une notion d'affinité entre les tâches. Le second, intitulé Subgraph-wise Placement, rassemble les tâches en groupes puis place les groupes de tâches sur les processeurs en se servant d'une relation d'affinité entre les groupes et les tâches déjà affectées. Ces algorithmes ont été testés sur des graphes, représentants des applications, possédant des topologies de types grilles ou de réseaux de portes logiques. Les résultats des placements sont comparés avec un algorithme de placement, présent dans la littérature qui place des graphes de tailles modérée et ce à l'aide de la métrique définie précédemment. Les cas d'application des algorithmes de placement sont ensuite orientés vers des graphes dans lesquels les poids des tâches et des arêtes sont variables similairement aux valeurs qu'on peut retrouver dans des cas industriels. Une heuristique de construction progressive basée sur la théorie des jeux a été développée. Cet algorithme, nommé Regret Based Approach, place les tâches une par une. Le coût de placement de chaque tâche en fonction des autres tâches déjà placées est calculée. La phase de sélection de la tâche se base sur une notion de regret présente dans la théorie des jeux. La tâche qu'on regrettera le plus de ne pas avoir placée est déterminée et placée en priorité. Afin de vérifier la robustesse de l'algorithme, différents types de graphes de tâches (grilles, logic gate networks, series-parallèles, aléatoires, matrices creuses) de tailles variables ont été générés. Les poids des tâches et des arêtes ont été générés aléatoirement en utilisant une loi bimodale paramétrée de manière à obtenir des valeurs similaires à celles des applications industrielles. Les résultats de l'algorithme ont également été comparés avec l'algorithme Task-Wise Placement, qui a été spécialement adapté pour les valeurs non unitaires. Les résultats sont également évalués en utilisant la métrique de placement aléatoire. / This Ph.D thesis is devoted to the study of the mapping problem related to massively parallel embedded architectures. This problem arises from industrial needs like energy savings, performance demands for synchronous dataflow applications. This problem has to be solved considering three criteria: heuristics should be able to deal with applications with various sizes, they must meet the constraints of capacities of processors and they have to take into account the target architecture topologies. In this thesis, tasks are organized in communication networks, modeled as graphs. In order to determine a way of evaluating the efficiency of the developed heuristics, mappings, obtained by the heuristics, are compared to a random mapping. This comparison is used as an evaluation metric throughout this thesis. The existence of this metric is motivated by the fact that no comparative heuristics can be found in the literature at the time of writing of this thesis. In order to address this problem, two heuristics are proposed. They are able to solve a dataflow process network mapping problem, where a network of communicating tasks is placed into a set of processors with limited resource capacities, while minimizing the overall communication bandwidth between processors. They are applied on task graphs where weights of tasks and edges are unitary set. The first heuristic, denoted as Task-wise Placement, places tasks one after another using a notion of task affinities. The second algorithm, named Subgraph-wise Placement, gathers tasks in small groups then place the different groups on processors using a notion of affinities between groups and processors. These algorithms are tested on tasks graphs with grid or logic gates network topologies. Obtained results are then compared to an algorithm present in the literature. This algorithm maps task graphs with moderated size on massively parallel architectures. In addition, the random based mapping metric is used in order to evaluate results of both heuristics. Then, in a will to address problems that can be found in industrial cases, application cases are widen to tasks graphs with tasks and edges weights values similar to those that can be found in the industry. A progressive construction heuristic named Regret Based Approach, based on game theory, is proposed. This heuristic maps tasks one after another. The costs of mapping tasks according to already mapped tasks are computed. The process of task selection is based on a notion of regret, present in game theory. The task with the highest value of regret for not placing it, is pointed out and is placed in priority. In order to check the strength of the algorithm, many types of task graphs (grids, logic gates networks, series-parallel, random, sparse matrices) with various size are generated. Tasks and edges weights are randomly chosen using a bimodal law parameterized in order to have similar values than industrial applications. Obtained results are compared to the Task Wise placement, especially adapted for non-unitary values. Moreover, results are evaluated using the metric defined above.
400

Evaluating the Use of the L1 in a French Language Classroom

Guidi, Joyce Esther Hiaumiti 28 December 2021 (has links)
Researchers have explored how different balances of first language (L1) and target language (TL) use in a foreign language classroom impact students' fluency and proficiency in TL acquisition. Research has shown that the use of the L1 in a foreign language classroom is done in order to determine the most effective way to raise the proficiency of second language learners to the level that is expected within their classrooms (Lee & Muncie, 2006). The use of the L1 is not something that is uncommon, even in the highest levels of foreign language instruction, although some believe it could inhibit learner growth in target language (TL) acquisition (Tanveer, 2007). Some scholars contend that there is a place for the L1 to be used in a second language classroom, rather than relying on complete usage of the TL (Biggs, 1999). Results have been mixed when it comes to whether or not the L1 should be used as much as the TL, and studies have seldom investigated what students and teachers believe regarding that matter. To this end, the present study examines the impact of the use of the L1 vs the use of the TL on 50 students at different levels in the French language classroom. Subjects were all enrolled in French classes ranging from the 101-level to the 201-level, and the 8 student instructors teaching these levels also participated in this study. Both a student survey and a teacher survey were administered at the end of the semester in order to look at the use of the TL vs the use of the L1 among students and teachers in their classrooms. Results show that the utilization of the L1 in foreign language classrooms is preferred by the students but that it is not fully justified. Numerous proponents of L1 use (Atkinson, 1987; Cook 2001; Swain & Lapkin, 2000; Wells, 1999) have cautioned against excessive use, instead recommending that it be used judiciously, and according to learner need. Future researchers might consider surveying students who are learning in an environment where L1 use is similar to student demand on this survey (very high, especially for things like giving instructions), as well as surveying students who are exclusively using TL in their learning environment.

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