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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.
331

Evaluation et traitement des polluants émis par un moteur thermique fonctionnant avec des biocarburants / Evaluation and treatment of polluants emitted by an engine fed with biofuels

Cosseron, Anne-Flore 29 October 2012 (has links)
Les biocarburants présentent une alternative prometteuse à l’utilisation de carburants fossiles. Cependant, l’augmentation de la quantité de biocarburants introduite dans les carburants nécessite de connaître leur impact sur les émissions de polluants. Le travail réalisé lors de cette thèse peut être décrit en deux parties : La première traite de l’évaluation des émissions de polluants réglementés et non réglementés émis par la combustion de biocarburants dans un moteur diesel. Différents biocarburants ont été testés : des esters méthyliques d’huile de soja et de colza, des esters éthyliques d’huile usagée et un carburant de référence exempt de tout biocarburant. Les résultats montrent que la nature des biocarburants ainsi que leur teneur ont un impact sur les polluants émis. Par exemple, une diminution de la taille des particules émises a été observée avec l’utilisation des esters méthyliques d’huile de soja. Le deuxième objectif de cette thèse concerne le piégeage des polluants Diesel, notamment des composés organiques volatils par des zéolithes. Plusieurs zéolithes ont été synthétisées puis caractérisées. Des tests d’adsorption par thermogravimétrie ont ensuite été réalisés au laboratoire avec différentes molécules sondes représentatives des polluants émis par les moteurs Diesel (le n-hexane, le p-xylène et l’acétone). Certaines zéolithes comme les zéolithes faujasite présentent des capacités d’adsorption intéressantes. Toutefois, la plupart des résultats montrent une diminution de la capacité d’adsorption avec l’augmentation de la température. Ces zéolithes ont ensuite été placées en sortie d’échappement d’un moteur diesel afin d’étudier leur capacité d’adsorption. / Nowadays, biofuels are a promising alternative to the use of fossil fuels. However, increasing the amount of biofuels introduced in fuels requires to know their impact on emissions pollutants.The work done in this thesis can be described in two parts: The first one deals with the evaluation of emissions of regulated pollutants (NOx, CO, CO2, O2, THC) and unregulated pollutants (volatile organic compounds, carbonyl compounds and fine particles (between 30 nm and 10 microns)) emitted by the combustion of biofuels in a diesel engine. Different biofuels have been tested: methyl esters of soybean oil and rapeseed oil, ethyl esters of used oil and a reference fuel free of biofuel. The results show that the nature of biofuels and their content have an impact on the pollutants emitted. For example, a decrease in the size of the particles emitted was observed with the use of methyl esters of soybean oil. The second objective of this thesis was to trap pollutants, like volatile organic compounds (VOCs) with zeolites. Several hydrophilic and hydrophobic zeolites have been synthesized and characterized. Adsorption tests were then carried by thermogravimetry with different probe molecules representative of pollutants from diesel engines (n-hexane, p-xylene and acetone). Some zeolites such as faujasite zeolites have interesting adsorption capacities. However, most of the results show a decrease in the adsorption capacity with the increase of the temperature. Then, these zeolites have been placed in the exhaust outlet of a diesel engine in order to study their adsorption capacity.
332

The Effects of Professional Development and Formative Assessment Quality on Students' Self-Regulation in Primary School Mathematics

Adewoye, Oluwakemi 01 January 2018 (has links)
Student self-regulation is associated with mathematics achievement in Nigerian primary schools, and formative assessment holds promise for increasing self-regulation. However, to date no research has explored teacher professional development (PD) for formative assessment and its effects on students' self-regulation in Nigerian primary schools. This quasi-experimental nonequivalent control group design used Desimone's teacher professional development conceptual framework, Popham's model for practicing formative assessment, and Zimmerman's concept of self-regulated learning. Research questions concerned whether differences existed in teachers' practice and students' self-regulation between two groups of Nigerian primary school mathematics teachers who received variations of professional development. The sample was 13 volunteer mathematics teachers (7 in a workshop plus follow-up group and 6 in a workshop-only group) and 183 students from 7 primary schools. Teacher formative assessment quality (FAQ) data was collected from 3 classroom observations and student end-of-project self-regulation was measured via a questionnaire. Descriptive analysis at the teacher level showed that teachers in the workshop-plus group had a higher level of FAQ than workshop-only teachers. A t test showed students with workshop-plus teachers had significantly higher self-regulation scores on average than students with workshop-only teachers, although FAQ did not correlate with students' self-regulation scores, possibly due to a small sample size. This study contributes to social change by providing supporting evidence for school administrators to provide workshop plus follow-up coaching PD to teachers to increase the quality of formative assessment, which may have implications for improving mathematics achievement among primary students in Nigeria.
333

The interaction of achievement goal orientations, self-regulated learning and learning environment in high school science classrooms

Iverach, Michael Robert January 2007 (has links)
Despite the substantial amount of education research on “teaching for understanding” and “learning for understanding” processes that has occurred in the fields of achievement goals, constructivist-based pedagogy, motivational beliefs and self-regulated learning there is little research that considers in unison the pillar constructs of these fields. Three studies comprised the present research which was designed to address the proposal that important social- and personal-based constructs associated with achievement goals, constructivist-based pedagogy, motivational beliefs, and self-regulated learning act in an interdisciplinary fashion to influence learning in the high school science classroom. All the large-scale quantitative studies presented a single-level structural equation model that was applicable to the general high school science student, controlling for the variance associated with age, gender, and student type (regular or selective high school student). Results from the two large-scale trait-level correlational studies of Study 1 (n = 655) and Study 2 (n = 617) using the Achievement Goals Questionnaire (Elliot & Church, 1997), Constructivist Learning Environment Survey (Taylor, Fraser, & Fisher, 1997) and the Motivated Strategies for Learning Questionnaire (Pintrich, Smith, Garcia, & McKeachie, 1991) as the main quantitative instruments found support for the hypothesis that a perceived emphasis on the constructivist-based pedagogical dimensions of personal relevance and student negotiation in science classrooms promotes the adoption of mastery-approach and intrinsic value. These analyses also showed the importance of self-efficacy in promoting mastery-approach, performance-approach and the use of regulatory strategies, and that test anxiety had positive associations with mastery-avoidance and performance-avoidance goals. / Study 3 comprised of two mini-studies that investigated the associations of competence perceptions, achievement goals and self-regulated learning in two science classroom learning contexts: teacher-led discussion (n = 451) and group work (n = 476). Using specifically developed context-level questionnaires, the results of these studies affirmed current theories concerning the interactions of self-efficacy, achievement goals, self-regulated learning (regulatory strategy use) and maladaptive strategy use. Students interviewed in Study 3 mostly reported the adoption of their achievement goals depended upon personal reasons that were commensurate with current achievement goal theory (Elliot, 1999) rather than specific classroom practices. The present research was also significant in that it tested the empirical stature of two frameworks by which social/cognitive research affiliated with learning environments, achievement goals and self-regulated learning may be conducted. Firstly, the results of the construct validity measures generated across Studies 1, 2 and 3 found support for the existence of the hypothesised 2 X 2 achievement goals framework (Elliot, 1999; Elliot & McGregor, 2001; Pintrich, 2000a). Secondly, the research introduced the tenets of a “context” hypothesis and found support for this perspective throughout the context-level studies. Adjunct multilevel multiple regressions were used in all the quantitative studies to examine the impact of subpopulation variables (age, gender, regular or selective high school student) and multiple goal interactions upon response variables, and to assess the variance attributed to the response variables at the class-level. Implications for the research disciplines studied are presented in terms of teaching practice, theory, future research and research methods.
334

運用自律學習機制提升閱讀標註學習成效研究 / A study on applying self-regulated learning mechanism for promoting learning performance of reading annotation

陳炎漳 Unknown Date (has links)
有鑑於數位閱讀已逐漸成為閱讀發展的新趨勢,許多研究著手於發展相關的閱讀系統或設備來輔助學習者進行閱讀學習。此外,如何幫助學生在進行英文閱讀學習時,增加對於文章的理解,已經成為很重要的研究課題。而基於網路學習環境進行數位閱讀學習時,學習者常常需要進行自主學習,因此學習者個人的自律學習能力成為影響數位閱讀學習成效的關鍵因素。本研究旨在探討運用具自律學習機制的閱讀標註系統是否具有提升國中英語閱讀學習成效的效益,研究採用準實驗研究法,以桃園縣某國中七年級二班的學生,分成實驗組與控制組,實驗組與控制組分別以「具自律學習機制的閱讀標註系統學習」及「不具自律學習機制的閱讀標註系統學習」進行英語閱讀學習,經過實驗處理後,接受「閱讀測驗後測」,以比較兩組學生在閱讀學習成效上的差異性,輔之以問卷調查實驗組學生對課程活動的態度看法,並以訪談作質性資料分析。最後,根據研究結果提出具體建議,以提供未來研究與教師在運用具自律學習機制之數位閱讀標註系統融入閱讀教學時之參考。本研究得到的研究結論如下: 一、 實驗組學習者採用具自律學習機制之數位閱讀標註系統,其英語閱讀學習成效顯著優於採用不具自律學習機制之數位閱讀標註系統的控制組學習者。 二、 實驗組學習者採用具自律學習機制之數位閱讀標註系統,其閱讀標註能力顯著優於採用不具自律學習機制之數位閱讀標註系統的控制組學習者。 三、 實驗組學習者中不同自律能力學習者其閱讀學習成效具有顯著差異。 四、 實驗組學習者中不同自律能力學習者其閱讀標註能力具有顯著差異。 五、 實驗組學習者中閱讀學習成效與閱讀標註能力有顯著相關且自律能力與學習成效呈現正相關 關鍵字:自律學習、數位閱讀、閱讀標註、閱讀學習成效 / In the consideration of that digital reading has become a new trend of reading development; many studies were conducted to develop related reading systems or equipments to assist learners on learning of reading. Moreover, how to help students improve comprehension while reading English is an important topic for research. Based on the characteristics of digital reading in the e-learning environment, in which learners often need self-regulated learning, the ability of self-regulated learning has become a key factor that affects the learning effects of reading. The purpose of the present study was to investigate whether the application of reading annotation system with self-regulated learning could increase the learning effects of English reading for junior high school students. The present study adopted quasi-experimental design method and the subjects were two classes of seventh graders in a junior high school in Taoyuan County. There were divided into experimental group and control group to learn English through reading, and were instructed respectively with “reading annotation system learning with self-regulated learning” and “reading annotation system learning without self-regulated learning.” After the experiment, “reading post-test” was conducted to compare the learning effects of reading for these two groups of students. Students in the experimental group were also surveyed by questionnaires and interviewed for qualitative data analysis. Finally, the researcher made suggestions according to the research results as references for future studies and for teachers who want to apply reading annotation system with self-regulated learning to reading instruction. The results of the present study were as the following: 1. The learning effects of English reading for learners in the experimental group with self-regulated reading annotation system were significantly greater than those who were in the control group without self-regulated reading annotation system. 2. The ability of reading annotation of the learners in the experimental group with self-regulated reading annotation system were significantly greater than those who were in the control group without self-regulated reading annotation system. 3. There were significant differences among the learning effects of reading for learners in the experimental group with different ability of self-regulated learning. 4. There were significant differences among the ability of reading annotation for learners in the experimental group with different ability of self-regulated learning. 5. For the learners in the experimental group, the learning effects of reading were significantly related to the ability of reading annotation; the ability of self-regulated learning was positively correlated with learning effects. Keywords: self-regulated learning, digital reading, reading annotation, learning effects of reading
335

二專生自我調整學習之理論建構與實證研究 / Theoretical Construction and Empirical Study of Self-regulated Learning of Two-year Junior College Students

陳品華 Unknown Date (has links)
本研究的主要目的,在於了解二專學生的自我調整學習及自我調整學習教學之效果。研究中除探討二專生自我調整學習所涉及之重要歷程與因素、檢視自我調整學習與學業表現之間的關連外,並驗證融入式自我調整學習策略教學之效果。 本研究採文獻探討與實證研究二部分進行之。首先,就自我調整學習之概念、理論與相關研究進行文獻分析,據以形成二專生自我調整學習之研究架構,而後,進行實證研究考驗之。實證研究方面,分別進行問卷調查及教學實驗二項研究,問卷調查係針對目前二專各類科學生進行抽樣調查,有效樣本1717人,分析並比較其於國文科的自我調整學習情形及學業表現;教學實驗則採準實驗設計,以二專四個班級共222名學生為對象,將自我調整學習策略教學融入實驗組之心理學課程之中進行之,分析並比較實驗組(N=110)與控制組(N=112)之自我調整學習及學業表現。 本研究根據研究發現,獲致結論如下: 一、 二專生的自我調整學習,主要包括學習的動機信念與學習策略的使用二個重要歷程,且此二歷程密切關連。 二、 二專生的自我調整學習策略,主要包括認知策略與意志控制策略二類,且此二類策略密切關連。 三、 二專生的個人變項會影響其自我調整學習。 四、 二專生的自我調整學習會影響其學業表現。 五、 自我調整學習策略教學可融入二專學科課程之中。 六、學習回饋為融入式自我調整學習策略教學之重要關鍵,應同時兼顧學習結果及學習歷程之回饋。 七、融入式自我調整學習策略教學可增進二專生自我調整學習策略的使用,並提昇其學業表現。 最後,本研究依據研究結論,提出對二專教師、學校、教育主管機關及未來研究之建議,以作為二專教學、教育政策實施及相關研究之參考。 / The main purpose of this research was to investigate the self-regulated learning of two-year junior college students and the effects of self-regulated learning intervention. In this research, the important processes and factors involved in self-regulated learning of two-year junior college students as well as their relationships with academic performance were examined. Besides, it validated the effects of integrated self-regulated learning strategy instruction. Employing both literature and empirical researches. It analyzed the concepts, theories, and relevant studies of self-regulated learning on the literature to construct the study framework first, and conducted empirical studies to validate it afterwards. The empirical studies included a survey as well as a teaching experiment. The survey resulted a valid sample totaled 1717, out of a random sample of the current two-year junior college students. The self-regulated learning and academic performance on Chinese learning were analyzed and compared. The teaching experiment was a quasi-experiment. With four classes totaled 222 as subjects; the experiment embedded strategy instruction in the Psychology curriculum of experiment group. The self-regulated learning and academic performance of both experiment group (N=110) and control group (N=112) were analyzed and compared. According to the findings, the conclusions were rendered as follows: 1. The self-regulated learning of two-year junior college students mainly consisted of two important processes: the motivational belief and the use of learning strategy. The two processes were interrelated. 2. The self-regulated learning strategy of two-year junior college students mainly consisted of two kinds of strategies: the cognitive strategies and the volitional control strategies. The two kinds of strategies were interrelated. 3. The personal variables of two-year junior college students would affect their self-regulated learning. 4. The self-regulated learning of two-year junior college students would affect their academic performance. 5. The self-regulated learning strategy instruction could be integrated in the curriculum of two-year college. 6. Learning feedback was the key factor in the integrated self-regulated learning strategy instruction. It should include learning result feedback and learning process feedback. 7. The integrated self-regulated learning strategy instruction could improve the use of self-regulated learning strategy and academic performance of two-year junior college students. Finally, based on the conclusions, it provided concrete suggestions for two-year junior college instruction, relevant educational policies, and further studies.
336

Re-establishment of connectivity for fish populations in regulated rivers

Calles, Olle January 2005 (has links)
<p>The hydropower industry has altered connectivity in many rivers during the last century. Many fish species depend on both an intact longitudinal connectivity to be able to migrate between spawning, feeding and winter habitats, and vertical connectivity for development and survival of incubating embryos and larvae in the gravel. The objective of this thesis was to examine problems and remedial measures associated with disrupted longitudinal and vertical connectivity in regulated rivers. The issue of longitudinal connectivity was studied in the River Emån by evaluating the efficiency of two nature-like fishways for anadromous brown trout. Telemetry studies showed that the combined efficiency for the two fishways in 2001-2004 was 60.5%. The passage efficiencies of both fishways were high for trout (89-100%), but also for other species such as chub, perch, tench, burbot and roach (74%). The attraction efficiencies were largely dependent on power plant operation, and generally high for the fishway situated next to the tail-race and low for the fishway situated inside the former channel. More than half of the trout spawners were also observed using the fishways for downstream passage. The densities of brown trout yearlings upstream of the fishways were higher after the fishways were built than during pre-fishway years. Smolts produced upstream of the fishways were observed migrating downstream in 2003-2005. The percentage of smolts that passed both power plants in was 51%, with losses being attributed to predation (15%), turbine-induced mortality (16%) and other reasons (18%). Turbine-induced mortality was higher (40%) at the power plant with four small Francis runners, than at the power plant with one large Kaplan runner (12%). The issue of vertical connectivity was studied in three rivers in Värmland, one unregulated, and two regulated, one of which had no minimum flow requirements. In the unregulated river, temporal patterns in hyporheic water chemistry correlated to variation in surface water chemistry and discharge as expected. In the regulated rivers, the hyporheic water chemistry showed little correlation to discharge or surface water chemistry. The intra-gravel water chemistry conditions for brown trout eggs were more favourable in the unregulated river, characterised by high oxygen levels, than in the two regulated rivers. The regulated river with no minimum flow requirements had critically low oxygen levels at the end of the incubation period.</p>
337

Deductions from employees' remuneration :seeking clarity in the law

Cara Cato January 2009 (has links)
<p><font size="3" face="Arial"><font size="3" face="Arial"> <p align="left">In this study, I will look at the common law principle of offset to see whether it can be applied to employers making deductions against employees for loss or damage. Notice is a quantifiable amount and is a legal debt / therefore. it should be able to be applied as an offset. Two subsections deal with deductions / after looking carefully at the wording of theses subsections I will try to determine whether the one is alternate to the other, or whether the narrow interpretation that the Department of Labour gives to the statute is accurate. A narrow interpretation of the law states that the employee must sign an acknowledgement of debt. However, employees often refuse to sign an acknowledgement of debt, thereby frustrating the law. Could this possibly have been the intentions of the drafters? Surely not, yet the Department of Labour, by having a narrow interpretation of the law, see it as such and as a result the employer is left out of pocket. In this mini-thesis, I will look at the way the law should be interpreted and the way it should be applied in practice.</p> <p>&nbsp / </p> </font></font></p>
338

Re-establishment of connectivity for fish populations in regulated rivers

Calles, Olle January 2005 (has links)
The hydropower industry has altered connectivity in many rivers during the last century. Many fish species depend on both an intact longitudinal connectivity to be able to migrate between spawning, feeding and winter habitats, and vertical connectivity for development and survival of incubating embryos and larvae in the gravel. The objective of this thesis was to examine problems and remedial measures associated with disrupted longitudinal and vertical connectivity in regulated rivers. The issue of longitudinal connectivity was studied in the River Emån by evaluating the efficiency of two nature-like fishways for anadromous brown trout. Telemetry studies showed that the combined efficiency for the two fishways in 2001-2004 was 60.5%. The passage efficiencies of both fishways were high for trout (89-100%), but also for other species such as chub, perch, tench, burbot and roach (74%). The attraction efficiencies were largely dependent on power plant operation, and generally high for the fishway situated next to the tail-race and low for the fishway situated inside the former channel. More than half of the trout spawners were also observed using the fishways for downstream passage. The densities of brown trout yearlings upstream of the fishways were higher after the fishways were built than during pre-fishway years. Smolts produced upstream of the fishways were observed migrating downstream in 2003-2005. The percentage of smolts that passed both power plants in was 51%, with losses being attributed to predation (15%), turbine-induced mortality (16%) and other reasons (18%). Turbine-induced mortality was higher (40%) at the power plant with four small Francis runners, than at the power plant with one large Kaplan runner (12%). The issue of vertical connectivity was studied in three rivers in Värmland, one unregulated, and two regulated, one of which had no minimum flow requirements. In the unregulated river, temporal patterns in hyporheic water chemistry correlated to variation in surface water chemistry and discharge as expected. In the regulated rivers, the hyporheic water chemistry showed little correlation to discharge or surface water chemistry. The intra-gravel water chemistry conditions for brown trout eggs were more favourable in the unregulated river, characterised by high oxygen levels, than in the two regulated rivers. The regulated river with no minimum flow requirements had critically low oxygen levels at the end of the incubation period.
339

The Effects of Self-evaluation Training on Writing of Students in Grades 5 & 6

Zapitis, Marina 11 August 2011 (has links)
The purpose of this action research is to discover how self-evaluation training affects students’ knowledge and understanding about their writing and needs for improvement. In this study of 46 fifth and sixth graders, students underwent a four-stage self-evaluation training process. This involved students in defining criteria for their stories, teaching them how to apply the criteria using a variety of samples, giving students feedback about their self-evaluations, and developing action plans The study showed that after the self-evaluation process was set into place, students had an increased awareness of what made a good fictional writing piece. The self-evaluation process helped students become more aware of writing practices and of themselves as a writer. The study also found that the self-evaluation process set clear guidelines for students, focused student attention on important writing criteria, and opened up the conversation between students and teachers about evaluation, goal setting and the writing process.
340

The Effects of Self-evaluation Training on Writing of Students in Grades 5 & 6

Zapitis, Marina 11 August 2011 (has links)
The purpose of this action research is to discover how self-evaluation training affects students’ knowledge and understanding about their writing and needs for improvement. In this study of 46 fifth and sixth graders, students underwent a four-stage self-evaluation training process. This involved students in defining criteria for their stories, teaching them how to apply the criteria using a variety of samples, giving students feedback about their self-evaluations, and developing action plans The study showed that after the self-evaluation process was set into place, students had an increased awareness of what made a good fictional writing piece. The self-evaluation process helped students become more aware of writing practices and of themselves as a writer. The study also found that the self-evaluation process set clear guidelines for students, focused student attention on important writing criteria, and opened up the conversation between students and teachers about evaluation, goal setting and the writing process.

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