有鑒於英文寫作能力日趨重要，英文寫作的教學也愈來愈受到重視。然而在高職英文寫作教學方面來看，其成效卻往往不彰。基於這個原因，研究者運用透過電子郵件之「過程寫作」教學法，期能對高職學生在英文寫作能力的提升上有所裨益。 本研究以北縣某高職綜高學術學程部五十八位二年級學生為研究對象，研究者教導實驗組學生運用「過程寫作」的策略，配合在電子郵件的環境下加強英文寫作的能力；控制組學生則僅接受「過程寫作」策略之教學。實驗前，對實驗組及控制組學生施予前測來檢視學生英文寫作能力之起點行為；實驗後，對實驗組及控制組學生施予後測來檢視學生英文寫作能力之進步情形。實驗終了，再以一問卷來探討實驗組學生對實驗之態度及其自評成效。 研究結果如下： 一、 透過電子郵件之「過程寫作」教學法對學生英文寫作能力確有助 益。實驗組後測成績高於控制組；再者，實驗組在其前後測比較 下，整體寫作能力有顯著之進步。 二、 在電子郵件的環境下運用「過程寫作」的策略幫助學生在作文中之 內容、組織、文法、用字體例方面有所助益。實驗組與控制組之進 步情形雖無顯著差異，實驗組進步情形仍大於控制組。 三、 實驗組學生對透過電子郵件之「過程寫作」教學法，持正面的態 度。 四、 實驗組學生認為在接受透過電子郵件之「過程寫作」教學法之後， 自己的英文寫作能力進步了。 最後，研究者根據上述研究結果，對高職英文作文教學提出建言，作為未來從事英文寫作教學之教師及研究人員參考。 / Owing to the importance of English writing ability on various purposes, teaching writing has received more and more attention nowadays. However, the traditional teaching and then learning process does not work on vocational high school students. This failure inspires the researcher to resort to alternative methods to upgrade his students' English writing ability. The present study was intended to prove that the instruction of process writing via E-mail is effective in enhancing students' English writing ability. Fifty-eight second-year students from two intact classes of Academic Oriented Course in a comprehensive high school in Taipei County participated in this study. The experimental group was taught to apply the strategies of process approach in an E-mail environment at every stage during the experiment while the control group was instructed in process writing strategies solely. Before the experiment, the pretest was used to indicate the starting points of students' writing proficiency. After the experiment, the posttest was administered to examine the effectiveness of process writing via E-mail. In addition, a response questionnaire was given to the experimental group to probe students' attitudes and their self-evaluation of the experiment. The results were as follows. First, the instruction of process writing via E-mail enhanced students' overall English writing ability. The experimental group outperformed the control group in total scores of the posttest. In addition, concerning the total scores between pretest and posttest, the experimental group made a significant progress. Second, the experimental group outperformed the control group in content, organization, grammar, diction, and mechanics after the experiment although the results showed no significant difference. Still, the experimental group made more progress in all five subskills than the control group did. Third, the majority of students in the experimental group responded positively to the instruction of process writing via E-mail. Last, most students in the experimental group considered they made a progress in their English writing ability after the experiment of process writing via E-mail. The present study concluded the effects of process writing via E-mail. Based on the results, the researcher provided writing teachers and educators with constructive suggestions for conducting a writing class or further studies.

The main goal of this thesis is to find and describe the evidence of bilingual communication of English language among Czech users of the social network Facebook. A qualitative method of both text document and semi-structured interviews with six active users was used to describe the type of bilingualism which occurs in the social media environment, in what situations and what is the user's motivation behind it. Therefore the main theoretical approaches I focus on are bilingualism and its place in the Czech Republic and the role of the English language in this socio-culture context. Furthermore I study the communication in an online environment: what are the specifications and what role does the CMC (computer-mediated-communication) play in relationship of the language and the user. Finally, I search for previous studies in the field of online bilingualism, social media preferably. The results show not only the Czech users are well situated within the discourse of English as (online) lingua franca, moreover they seem to be very active in self-imposed code-switching into the English language. The data acquired through the interviews helped to identify bilingualism occurs on both levels of code-switching and code-mixing. Additionally, Anglicism's in the Czech language were reported widely.

<p>This thesis describes the implementation of a real-time, full search, 16x16 bidirectional motion estimation at 24 frames per second with the record performance of 155 Gop/s (1538 ops/pixel) at a high clock rate of 125 MHz. The core of bidirectional motion estimation uses close to 100% FPGA resources with 7 Gbit/s bandwidth to external memory. The architecture allows extremely controlled, macro level floor-planning with parameterized block size, image size, placement coordinates and data words length. The FPGA chip is part of the board that was developed at the Institute of Computer & Communication Networking Engineering, Technical University Braunschweig Germany, in collaboration with Grass Valley Germany in the FlexFilm research project. The goal of the project was to develop hardware and programming methodologies for real-time digital film image processing. Motion estimation core uses FlexWAFE reconfigurable architecture where FPGAs are configured using macro components that consist of weakly programmable address generation units and data stream processing units. Bidirectional motion estimation uses two cores of motion estimation engine (MeEngine) forming main data processing unit for backward and forward motion vectors. The building block of the core of motion estimation is an RPM-macro which represents one processing element and performs 10-bit difference, a comparison, and 19-bit accumulation on the input pixel streams. In order to maximize the throughput between elements, the processing element is replicated and precisely placed side-by-side by using four hierarchal levels, where each level is a very compact entity with its own local control and placement methodology. The achieved speed was further improved by regularly inserting pipeline stages in the processing chain.</p>

社交網站Facebook鼓勵使用者將真實世界中的人際關係串連至線上空間，與各種親疏遠近的朋友進行互動與維持情感交流。隨著社交規模與範圍的擴大，Facebook使用者需要透過規格化或公式化的互動，確保人際網絡的穩定交流。這些行為經過反覆實踐，發展為社交互動儀式。然而，互動行為本身卻與社交初衷逐漸背離。因此，本研究關注的正是Facebook上的互動儀式鏈如何呈現，以及使用者社交行為與意義之間產生落差，導致「行禮如儀」的原因。 本研究以社會學者Goffman（1955）互動儀式與Collins（2004）互動儀式鏈的理論為基礎，探討Facebook的網路中介儀式形成的契機與淪於形式的可能。研究方法方面，本研究選出四則關鍵個案，先以內容分析檢視互動儀式鏈中各項元素的組成；再從個案中選取具代表性的當事人與參與者進行深度訪談，進一步探究實踐互動儀式的原因、時機與對象等細節，並檢視互動儀式過程與結果。 研究結果顯示，雖然社交訊息事件都有機會發展為完整的互動儀式鏈，不過訊息事件的類型差異會影響互動儀式鏈的參與形式。此外，研究發現乍看毫無意義的網路互動行為（尤指按讚）並非如過往研究提到的扁平單一，甚至略帶貶意。這些互動其實乘載多重含意，例如：避免表錯情的慰問、掩飾內心掙扎的祝福、欲辯忘言的關注、對多義訊息的部分贊同等。每當使用者內心與行動不一致或脫鉤時，這些行為便成為每一次的緩衝，調解了「口不對心」的矛盾。 上述貌似「行禮如儀」的社交互動行為隨著訊息事件的種類而變化，行動意涵亦不停流動、轉變，逐漸成為眾人心照不宣的隱藏邏輯，內化成為使用者的行動策略。成為具有「僵固的儀式形式，多元流動的儀式意義」的互動行為，亦可作為網路世代專屬的行動符號。 / Social network sites, such as Facebook, enable users to interact with friends and maintain their relationship. The growing scope and scale of social network require users to cope with huge numbers of friends in formulated and standardized ways. These formulated actions practiced repeatedly on Facebook have become ritualized and thus shape the particular cultural landscape. However, these interaction actions gradually become alienated from original social intents. Facebook users tend to push “Like” bottom whenever they read friends’ news updates, but they just go through the motion without any meaning. This particular research applies sociologist Goffman’s interaction ritual theory and Collin’s interaction ritual chain theory to the context of Facebook behavior. The researcher attempts to answer 2 questions: 1. What a complete social interaction ritual chain would be like on Facebook? And what are its ritual ingredients and outcomes? 2. Does social interaction behavior mismatch its social intent? If the gap exists, why does it happen? This research collects data from researcher’s 750 friends’ information in time frame from March 2013 to April 2013. Four Facebook events are chosen as critical cases. Content analysis and deep interview are employed to discover the ingredients, process and outcomes of interaction ritual chains and every detail on Facebook. The result indicates it’s highly possible that every social information event would develop a complete interaction ritual chain. But the difference of event characters may have impacts on people’s forms of participation. Secondly, Facebook users often depreciate the meaning of “Like”, however “Like” turns out to show multiple meanings. Whenever Facebook users’ physical action couldn’t match attempts, “Like” would serve as the buffer solving the inconsistency. Finally, pushing “Like” bottom becomes “formulated but with multiple meanings”, and it also becomes exclusive action symbol of Facebook generation.

This thesis describes the implementation of a real-time, full search, 16x16 bidirectional motion estimation at 24 frames per second with the record performance of 155 Gop/s (1538 ops/pixel) at a high clock rate of 125 MHz. The core of bidirectional motion estimation uses close to 100% FPGA resources with 7 Gbit/s bandwidth to external memory. The architecture allows extremely controlled, macro level floor-planning with parameterized block size, image size, placement coordinates and data words length. The FPGA chip is part of the board that was developed at the Institute of Computer &amp; Communication Networking Engineering, Technical University Braunschweig Germany, in collaboration with Grass Valley Germany in the FlexFilm research project. The goal of the project was to develop hardware and programming methodologies for real-time digital film image processing. Motion estimation core uses FlexWAFE reconfigurable architecture where FPGAs are configured using macro components that consist of weakly programmable address generation units and data stream processing units. Bidirectional motion estimation uses two cores of motion estimation engine (MeEngine) forming main data processing unit for backward and forward motion vectors. The building block of the core of motion estimation is an RPM-macro which represents one processing element and performs 10-bit difference, a comparison, and 19-bit accumulation on the input pixel streams. In order to maximize the throughput between elements, the processing element is replicated and precisely placed side-by-side by using four hierarchal levels, where each level is a very compact entity with its own local control and placement methodology. The achieved speed was further improved by regularly inserting pipeline stages in the processing chain.

This thesis is concerned with investigations on two related issues of turbulent jet diffusion flame, namely (a) stabilization at liftoff and (b) autoignition in a turbulent jet diffusion flame. The approach of Conditional Moment Closure (CMC) has been taken. Fully elliptic first order CMC equations are solved with detailed chemistry to simulate lifted H2/N2 flame in vitiated coflow. The same approach is further used to simulate transient autoignition process in inhomogeneous mixing layers. In Chapter 1, difficulties involved in numerical simulation of turbulent combustion problems are explained. Different numerical tools used to simulate turbulent combustion are briefly discussed. Previous experimental, theoretical and numerical studies of lifted jet diffusion flames and autoignition are reviewed. Various research issues related to objectives of the thesis are discussed. In Chapter 2, the first order CMC transport equations for the reacting flows are presented. Various closure models that are required for solving the governing equations are given. Calculation of mean reaction rate term for detailed chemistry is given with special focus on the reaction rates for pressure dependent reactions. In Chapter 3, starting with the laminar flow code, further extension is carried to include kε turbulence model and PDF model. The code is validated at each stage of inclusion of different model. In this chapter, the code is first validated for the test problem of constant density, 2D, axisymmetric turbulent jet. Further, validation of PDF model is carried out by simulating the problem of nonreacting jet of cold air issuing into a vitiated coflow. The results are compared with the published data from experiments as well as numerical simulations. It is shown that the results compare well with the data. In Chapter 4, numerical results of lifted jet diffusion flame are presented. Detailed chemistry is modelled using Mueller mechanism for H2/O2 system with 9 species and 21 reversible reactions. Simulations are carried out for different jet velocities and coflow stream temperatures. The predicted liftoff generally agrees with experimental data, as well as joint PDF results. Profiles of mean scalar fluxes in the mixture fraction space, for different coflow temperatures reveal that (1) Inside the flamezone, the chemical term balances the molecular diffusion term, and hence the structure is of a diffusion flamelet for both cases. (2) In the preflame zone, the structure depends on the coflow temperature: for low coflow temperatures, the chemical term being small, the advective term balances the axial diffusion term. However, for the high coflow temperature case, the chemical term is large and balances the advective term, the axial diffusion term being small. It is concluded that, liftoff is controlled (a) by turbulent premixed flame propagation for low cofflow temperature while (b) by autoignition for high coflow temperature. In Chapter 5, the numerical results of autoignition in inhomogeneous mixing layer are presented. The configuration consists of a fuel jet issued into hot air for which transient simulations are performed. It is found that the constants assumed in various modelling terms can severely influence the results, particularly the flame temperature. Hence, modifications to these constants are suggested to obtain improved predictions. Preliminary work is carried out to predict autoignition lengths (which may be defined by Tign × Ujet incase of jet- and coflowvelocities being equal) by varying the coflow temperature. The autoignition lengths show a reasonable agreement with the experimental data and LES results. In Chapter 6, main conclusions of this thesis are summarized. Possible future studies on this problem are suggested.

This work describes three alternative processes for producing microfibrillated cellulose (MFC; also referred to as cellulose nanofibrils, CNF) in which bleached pulp fibres are first pretreated and then homogenized using a high-pressure homogenizer. In one process, fibre cell wall delamination was facilitated by a combined enzymatic and mechanical pretreatment. In the two other processes, cell wall delamination was facilitated by pretreatments that introduced anionically charged groups into the fibre wall, by means of either a carboxymethylation reaction or irreversibly attaching carboxymethylcellulose (CMC) to the fibres. All three processes are industrially feasible and enable energy-efficient production of MFC. Using these processes, MFC can be produced with an energy consumption of 500–2300 kWh/tonne. These materials have been characterized in various ways and it has been demonstrated that the produced MFCs are approximately 5–30 nm wide and up to several microns long. The MFCs were also evaluated in a number of applications in paper. The carboxymethylated MFC was used to prepare strong free-standing barrier films and to coat wood-containing papers to improve the surface strength and reduce the linting propensity of the papers. MFC, produced with an enzymatic pretreatment, was also produced at pilot scale and was studied in a pilot-scale paper making trial as a strength agent added at the wet-end for highly filled papers. / <p>QC 20150126</p>

文本的意義不僅是在觀看時協商，同時在對話中決定。本文目的在於了解電視劇迷在網路社群中談論電視劇的互動型態，以及如何實踐身為劇迷的身份。這個電視劇迷集結的網路空間，同時是虛擬社群、觀眾社群、也是迷的實踐社群的集合體。 研究過程以中情局BBS站中三個電視劇討論區以及奇摩家族中二個電視劇討論區為觀察主體，對討論區的文章作歸納分析、訪問討論區管理者以及進行迷們的電子問卷調查。研究發現，電視劇討論區受訪者認可其社群的存在，並感受尊敬、友善、溫馨、互助氣氛，但電視劇的播出壽命會主導著電視劇迷社群的興盛。這並非指該社群會消失，而是這群迷會轉往其它地方繼續存在。電視劇迷看電視劇原因以「喜愛該劇演員」為主，而電視劇討論區聚集了不同演員的支持者，因此電視劇討論區的凝聚力比起劇中演員的專門討論區來得小。 對電視劇迷群而言，電視劇觀看過程延攬至和朋友、同學、父母每日的對話，並融入網路這新興的口語書寫文化中。他╱她們從消化電視劇所提供的素材再生產出網路討論的文本，藉由對文本的共同詮釋來獲得歸屬感和友誼。 電視劇迷是具生產性的一群，不僅由書寫談論賦與媒體文本意義、創作同題材的網路小說，更聚集迷群力量，抗議製作體系拖戲及希望修改故事線。在討論區互動中，迷們接合現實空間和網際空間的分界，實踐、交換迷身份展現的論述。

Made available in DSpace on 2014-12-17T14:06:44Z (GMT). No. of bitstreams: 1 TulioWBJ.pdf: 572575 bytes, checksum: 5effde52c942d11015aa333c7bd07b5f (MD5) Previous issue date: 2008-02-29 / Oil well cementing materials consist of slurries of Special class Portland cement dispersed in water. Admixtures can be used to provide the necessary fluidity, so the material can be efficiently pumped down as well as penetrate porous rocks with controlled filter loss. Construction admixtures can be used to modify the properties of oil well cements provided they can withstand and hold their properties at the higher than ambient temperatures usually encountered in oil fields. In civil construction, superplasticizer play the role of dispersants that reduce the facto r of water cement improve mechanical properties and fluidity of the cement, whereas anti-segregation agents improve the workability of the slurry. In the present study, oil well cement slurries were produced adding both a dispersant and an anti-segregation agent conventionally used in Portland CPII-Z-32 RS cement aiming at materials for primary cementing and squeeze operations. Three basic aspects were evaluated: fluidity, filter loss and the synergetic effect of the admixtures at two temperatures, i.e., 27?C and 56?C, following API RP 10B practical recommendations. The slurries were prepared using admixture concentrations varying from 2.60 Kgf/m3 (0.02 gallft3) to 5.82 Kgf/m3 (0.045 galJft3) BWOC. The density of the slurries was set to 1.89 g/cm3 (15.8 Ib/gal). 0.30 to 0.60% BWOC of a CMC-based anti-segregation agent was added to the cement to control the filter loss. The results showed that the addition of anti-segregation at concentrations above 0.55% by weight of cement resulted in the increased viscosity of the folders in temperatures evaluated. The increasing the temperature of the tests led to a reduction in the performance of anti-segregation. At concentrations of 5.20 kgf/m3 (0,040 gallft3) and 5.82 Kgf/m3 (0,045 gal/ft 3) observed a better performance of the properties evaluated in the proposed system. At low temperature was observed instability in the readings of rheology for all concentrations of anti-segregation. Contents that increasing the concentration of anti?-segregation is limited concentrations greater than 0.55 % BWOC of the CMC in temperature analyzed. The use of the system with CMC promoted a good performance against the properties evaluated. The principal function of anti?-segregation was optimized with increasing concentration of superplasticizer, at temperatures above the 2rC. The study of the behaviour of systemic additives, resulting in slurries of cement, which can be optimized face studies of other intrinsic properties in oil fields / A pasta de cimento Portland ? uma mistura de part?culas s?lidas de cimento dispersas em ?gua. Tal sistema deve possuir fluidez suficiente para penetrar de forma eficiente em meio poroso, al?m de proporcionar controle na ?gua perdida por filtrado na forma??o, garantindo o sucesso da opera??o de bombeio. Em determinados campos as condi??es geol?gicas das forma??es, bem como a profundidade das faces explorat?rias do po?o podem favorecer ao acr?scimo de temperatura. Na constru??o civil os superplastificantes reduzem o fator ?gua cimento das argamassas proporcionando aumento de propriedades como resist?ncia mec?nica e fluidez, j? o anti-segregante proporciona uma melhor trabalhabilidade das argamassas. Sistemas com a adi??o de dispersantes e anti?segregante utilizados convencionalmente em cimento Portland CPII-Z-32 RS foram analisados em pastas de cimento Portland Especial, utilizadas para opera??es de squeeze e cimenta??o em po?os petrol?feros, com ?nfase em tr?s aspectos: fluidez, perda do volume de filtrado e efeito sinerg?tico. Os par?metros analisados foram estudados por meio de ensaios de desempenho nas temperaturas de 2rC e 56?C, seguindo as recomenda??es pr?ticas da norma API RP 108. Para o estudo foram selecionados materiais com car?ter dispersante como superplastificantes. e preparadas pastas com concentra??es variando de 2,60 Kgf/m3 (0,02 gal/p?3) a 5,82 Kgf/m3 (0,045 gal/p?3) em peso de cimento, com densidade constante de 1,89 g/cm3 (15,8 Ib/gal). Para o controle da ?gua perdida por filtra??o foi utilizado um agente anti-segregante a base de CMC com concentra??es variando de 0,30 % a 0,60 % em peso de cimento. Os resultados mostraram que a adi??o do anti-segregante em concentra??es acima de 0,55 % em peso de cimento resultou no aumento da viscosidade das pastas nas temperaturas avaliadas. Foi verificado que o aumento da temperatura dos testes provocou uma redu??o no desempenho do anti-segregante. Nas concentra??es de 5,20 kgf/m3 (0,040 gal/p?3) e 5,82 Kgf/m3 (0,045 gal/p?3) observou-se um melhor desempenho das propriedades avaliadas no sistema proposto. Na temperatura ambiente foi verificado instabilidade nas leituras de reologia para todas as concentra??es do anti-segregante. Foi verificado que o aumento da concentra??o de anti-segregante ? limitada as concentra??es superior a 0,55 % em peso de cimento nas temperaturas analisadas. O uso do sistema contendo superplastificante, aliado ao anti-segregante promoveu um bom desempenho face ?s propriedades reol?gicas e de controle de filtrado das pastas. A fun??o principal do anti-segregante foi otimizada com o aumento da concentra??o do superplastificante, a temperaturas acima da ambiente. Por?m o aumento da concentra??o do agente dispersante nas pastas de cimento pode provocar o retardamento das pastas em temperaturas pr?ximas da ambiente. O estudo do comportamento sist?mico dos aditivos resultou na obten??o de pastas de cimento, que podem ser otimizadas face estudos de outras propriedades intr?nsecas a sua utiliza??o nas opera??es em campos petrol?feros

Cette recherche a pour objet un dispositif de télécollaboration asymétrique qui met en relation des apprentis tuteurs de FLE avec des apprenants distants. Notre objectif est d’examiner le parcours de l’apprenant à travers ses activités et ses échanges avec les tuteurs. La communication entre les deux groupes est exclusivement médiatisée par ordinateur à travers une plateforme d’apprentissage en mode asynchrone (forums) et quasi-synchrone (clavardage). La recherche est focalisée sur les apprenants et elle cherche à voir si leurs échanges en ligne avec les tuteurs se révèlent potentiellement acquisitionnels au plan de l’interaction verbale et de la réflexion sur la langue.La recherche s’inscrit dans le domaine des sciences du langage et plus particulièrement de la didactique des langues, dans la lignée des recherches en apprentissage des langues assisté par ordinateur (ALAO, CALL en anglais). Ayant comme objectif de mieux comprendre le vécu et l’activité des apprenants, de manière holistique, nous faisons appel à d’autres champs d’études, à savoir les sciences de l’éducation, les sciences de l’information et de la communication, les technologies éducatives et la psychologie des apprentissages. Ainsi, notre cadre conceptuel est transdisciplinaire.Nos analyses reposent sur deux axes. Le premier a pour but d’examiner la dimension communicationnelle des échanges en ligne à travers les tâches proposées aux apprenants par les tuteurs. Le second vise à étudier les pratiques « méta » des apprenants, issues du feedback correctif que les tuteurs donnent aux apprenants dans le cadre de leurs tâches. Nous avons recueilli plusieurs types de données et pour répondre à nos questions de recherche, nous recourons à leur triangulation. Nous avons adopté une démarche descriptive et notre analyse est qualitative et empirico-inductive. Nous avons aussi fait appel à l’approche systémique qui nous permet d’étudier l’ensemble des éléments de notre système, interreliés de telle manière que tout changement d’un paramètre a un effet sur les autres.Cette étude a deux visées : herméneutique et praxéologique. D’une part, nous cherchons à étudier et à comprendre l’activité d’apprentissage à travers les technologies tout en prenant en compte les relations qui existent entre le contexte et le sens que l’apprenant accorde à l’apprentissage dans ce même contexte. D’autre part, la recherche propose quelques pistes pédagogiques, interactionnelles et ingénieriques fondées sur les échanges observés ; l’objectif est d’améliorer les pratiques d’apprentissage à partir de la télécollaboration asymétrique étudiée grâce à la modélisation de certains paramètres. / This research looks into an asymmetric telecollaborative exchange, where tutor trainees of French as a foreign language communicate with distance learners. Our work examines students’ paths through their learning activities and exchanges with the tutors. Communication between the two groups is exclusively mediated by computer, via a learning platform in asynchronous and quasi-synchronous mode (forums and chats respectively). The research focuses on learners and aims at studying whether online exchanges with tutors prove to be potentially acquisitional in terms of verbal interaction and reflection on language.The research focuses on language sciences and in particular on applied linguistics in line with research on computer assisted language learning (CALL). With a view to better understanding learners’ experience and activity, in a holistic approach, we also refer to other fields of study, such as educational sciences, information and communication sciences, educational technologies and psychology of learning. Thus, our conceptual framework is transdisciplinary.Our analysis consists of two phases. Firstly, we examine the communicative dimension of online exchanges through tasks designed for the learners by the tutors. Secondly, we study learners’ “meta” practices, coming from the tutors’ corrective feedback on their tasks. We collected several types of data and, in order to answer to our research questions, we used data triangulation. We used a descriptive approach and our analysis is qualitative and empirico-inductive. We also used a systemic approach, which allows us to examine all of the elements of our system. These elements are interrelated in such a way that any change of one parameter has an effect on the others.This study has two goals: hermeneutics and praxeological. On the one hand, we intend to study and understand learning activity through technology, while taking into account the relationship between the context and the meaning that the learner gives to learning within this context. On the other hand, our research suggests some pedagogical leads based on the exchanges we studied; our aim is to improve learning practices from asymmetric telecollaboration observed by modelling certain parameters.