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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.
151

A Geophysical Investigation of Hydraulic Pathways at the Panola Mountain Research Watershed

Hebert, Gabriel John 26 August 2005 (has links)
The Panola Mountain Research Watershed (PMRW) is a 41 ha forested watershed, located 25 km southeast of Atlanta, Georgia. Within that watershed is a 10 ha sub-catchment which contains the headwaters of the watersheds main stream, as well as two outcrops of Panola Granite (Burns et al. 2001). On the hill-slope below the northernmost outcrop, is a 20m long trench that has been excavated down to bedrock, a depth that ranges from 0.5-1.5m. In previous studies (Burns et al., 2001; Freer, et al., 2002), discharge through the overlying soils was measured along the trench in 2m sections across the full length of the trench. In those studies, it was assumed that the underlying bedrock was impermeable. However, Burns et al. (2003) showed that the riparian groundwater downslope from the trenched hillslope site was only 6 to 7 years old. The permeability of the Panola granite in question was proven by a recent Lithium- Bromide line tracer experiment -van Meerveld et al., in review. Due to the levels of bromide in the bedrock measured at the trench, it has become apparent that fluid is being lost to hidden hydraulic pathways, those probably being fractures. The objective of this thesis is to test the viability of using shallow seismic reflection to map out fracture zones at the trenched hillslope site, using GPR and shallow seismic refraction as supplemental techniques to verify the interpretation. Data from two seismic common shot point (CSP) surveys permitted an image of the soil/bedrock interface to be constructed, as well as enabling an acoustic velocity profile to be calculated for the area. This velocity profile is then used with data from five reflection surveys (one seismic and four radar) to create vertical profiles of the subsurface. Although the resulting SSR profile is less than optimum, higher amplitude arrivals related to structure were still able to be detected. From this profile, as well as those from the GPR survey, it can be concluded that the proposed hidden hydraulic pathways due indeed exist, and also that they can be accurately mapped out using the previously mentioned geophysical methods.
152

An observation on the leader¡¦s feeding back for learning and visiting.

Lin, Wen-jyh 22 July 2010 (has links)
It is direct response on a pure reaction that a leader took a learning and visiting. And it means that all of the spirit and style deep in his mine will explosion at any time and any where. Even though account a character later, will be described included a real; aconcept and the other spirit also be exploded and you will find some philosophy of management that you never found before if you carefully. The leader visited to the site of manufacturing that different from around the table in the office and will contact and feel all of the men; products; facilities; the environment and every thing around the site directly. The feeling is really, the reaction is true and the response normally representing the spirit of the leader. The spirit including something will feed back to the men, whom interact with the leader. You will found that a success leader all ways have some character form the feed backs. On the observation we have found some conclusions as follow: 1. A success leader has the modest and studious characters. 2. A success leader has the conscientious and never stop till find out the cause curiously characters. 3. A success leader will sight on the future and carry out the strategies for the futures. 4. A success leader will seek the truth from the facts and take streamlining. 5. A success leader will try to get all of the information and disseminate the useful news in time. 6. A success leader is a disseminator of experience and never limited in the organization or the countries.
153

Analysis of Hemispherical Microlens Anti-Reflection Coating Solar Cells

Yen, Cheng-Feng 26 July 2010 (has links)
For the shortage of energy and the environmental issues, the development of solar cells has become an important technology. However, solar cells have low efficiency of energy conversion due to their high surface reflection on a flat Si substrate which is 38 %. To decrease the surface reflectance of the silicon solar cells, anti-reflection coatings (ARCs) are proposed on the solar cells. We use Lighttools software to investigate several kinds of ARCs to decrease the surface reflectance. We first consider the reflectance of the single-layer ARC with quarter wavelength. It can effectively decrease about 30 % surface reflection as compared with a flat Si substrate. The half-cylinder texture and the wave texture are designed on a PMMA single-layer coating. It is found that the half-cylinder ARC and the wave ARC can usefully diminish the surface reflectance for perpendicular light. Low reflectance can be achieved in the hemispherical microlens ARCs over an extended spectral region for omnidirectional incident light. The impact of the microlens sizes, periods, and arrangements are investigated. The lowest normal reflectance of the closely-packed triangular-lattice hemispherical microlens ARC is 4.8%. By adding smaller hemispherical microlenses, the surface reflectance of the hemispherical microlens ARC can be as low as 1.86 %. To obtain the lowest average surface reflectance, both-sided patterned surface texture ARCs are designed. Their lowest average surface reflectance is 2.24%. Finally, we simulate the reflectance of the nanowire ARCs. The influence of the wire length and the angle of inclination are discussed for high-efficiency and low-cost solar cells.
154

Effect of Microblogging Prompts Strategy on Learner's Reflection Level

Huang, I-Fang 28 July 2010 (has links)
Reflection plays an important role in the learning process. A good learning strategy is supposed to improve a learner¡¦s reflection level.The Prompts is one of the learning strategies to promote a learner¡¦s reflection level. As a result, a well-formed prompt strategy fitting what a learner has or is situated in the right context will be the key factor contributing to promote a learner¡¦s reflection level. This study applied the prompts strategy in a Microblogging environment and named it as ¡§Microblogging Prompts Strategy¡¨. It¡¦s expected that designed microblogging prompts strategy would have positive effects on a learner¡¦s reflection level, metacognition and learning performance. The results show that microblogging prompts strategy has significantly positive effects on a learner¡¦s reflection level and metacognition but no positive effects on learner¡¦s learning performance. In addition to this, this study further investigates the learner¡¦s usage attitude and feedback toward the microblogging prompts steategy. Finally, the learners accessing microblogging prompts system by mobile devices were interviewed in order to investigate the potential issues and prombles of this strategy in the mobile learning environment.
155

Effect of Adaptive Reflection Prompt on Learner's Reflection Level in a u-Learning Environment

Jang, Yu-ruei 09 August 2010 (has links)
Many research have shown that reflection is one of the important factors in the learning process. It is then recommended that teacher should adopt various prompt techniques to promote learners¡¦ reflection ability in traditional classrooms. However, there are still very few studies on how to apply this kind of teaching strategy in outdoor learning environments. Therefore, this study designed an adaptive prompts strategy by matching prompt types with learning styles to improve learners¡¦ reflection levels in an outdoor u-learning environment. We conducted an experiment using the designed and developed learning system in a butterfly ecology garden. Two classes of thirty-nine 5th grade primary school students were involved in the experiment. The result shows that the reflection levels of the learners whose learning styles matched with the appropriate prompt types were higher than that the non-matched group of learners. Therefore, it is evidenced that the designed adaptive reflection prompt system is useful in an outdoor u-learning environment.
156

A Science Teacher¡¦s Reflection on Innovative Teaching Process

Wei, FanPai 01 September 2011 (has links)
By autobiography retrospection and self reflection, this research aims to describe what influence an individual and his learning process pose on a teacher¡¦s way of creative teaching. Personal creative teaching ideas and implementation patterns are presented through the case-sharing of creative teaching. I attempted to find out the teaching concept and the method of cultivating students¡¦ creativity, further to promote teaching efficiency, and to share with parents and education-related personnel with the results as the reference for future planning and executing creative teaching activities. Main findings in this research are: 1. Growing in a respectful, liberal, open family lays the solid foundation of future creative teaching. 2. During schooling and working, theories discussion and teaching experiences sharing with professors and colleagues benefit the practice of creative teaching. 3. That a school respects teachers¡¦ professional teaching provides the room of freedom of creative teaching, which benefits teachers conducting creative teaching activities. 4. Maintaining characteristics such as curiosity, independence, and innocence gives the researcher the impetus to urge creative teaching. 5.Creative teaching should be that on the basis of students learning demands and their living experiences, teachers carefully design the teaching content both informatively and entertainingly; in addition, provide students the effective learning pattern to absorb knowledge and skills by actual operation. In the end, according to the findings of this research, suggestions are made and shared with parents and teachers for future reference of planning and executing creative teaching activities.
157

Research on Regrowth by Molecular Beam Epitaxy and Silicon Oxide Coating

Lee, Po-Tsong 09 July 2004 (has links)
The thesis consists of two aspects: (1) Research on regrowth by molecular beam epitaxy, and (2) Silicon monoxide coating. In part one, we used (NH4)2Sx to passivate the InAlGaAs/InP surface. From the X-ray photoelectron spectroscopy (XPS), the passivated surface shows a dramatic reduce of oxidation. A preparation chamber for the regrowth has been setup to proceed the sulfur passivation method. We can obtain a clean surface for regrowth after heating and putting samples in the high vacuum chamber. In the design of regrowth layers, we have found the best waveguide structure by regrowth. When the ridge width is 2.5 mm with etching depth 1.4 mm, a circular mode profile can be obtained by Fimmwave simulation. In the integration between devices, we have designed the best waveguide structure after regrowth by BeamProp 3D. The best design will make the propagation loss smaller than 0.21%. The second part is anti-reflection (AR) coating by silicon monoxide (SiO) deposition. The SiO refractive index of 1.8837 was obtained by transmission, and ellipsometer measurements. The corresponding AR coating thickness for InP substrate is 2057 &#x00C5;. In order to make AR coating on lasers of different effective index, we design the double-layer coating. For Beam Expander Semiconductor Optical Amplifier (BESOA), SiO2 / SiO and Si3NX / SiO double-layer coatings were compared with SiO single layer. The reflectance (R) was reduced 16.86 % and 25.12 %, respectively, and the R < 1% bandwidth extends 200 &#x00C5;.
158

Effects of high level prompts and peer assessment on learner reflection in a web-based learning environment

Wu, Kung-Ting 23 July 2007 (has links)
In recent years, E-learning has become more and more popular, and reflection is one of the most important factors that affect learning. Therefore, the issue on how to motivate learners to reflect on web-based learning is worth discussing. Our study use high level prompts and peer assessment to investigate how these two factors influence learners¡¦ reflection level, reflection attitude, and reflection intention. 157 college students were asked to use the system designed in this research, and the experimental learning subject was biology. Fourteen learning situations are presented in this research according to the difference of high level prompts (giving/not giving prompts), peer assessment (no peer assessment, peer observation, and peer feedback), observation (high quality/low quality observation), feedback (positive/negative feedback). The learners were randomly assigned to one situation. The result showed that giving high level prompts and high quality observation can improve learners¡¦ reflection level. If a learner is only given high quality observation, though not given high level prompts, his reflection level is still equal to the one who is given high level prompts but not given high quality observation. The result also showed that if a learner receives positive feedback, his reflection attitude and reflection intention will be higher than the one who receives negative feedback.
159

反すうに関する心理学的研究の展望 : 反すうの軽減に関連する要因の検討

松本, 麻友子, MATSUMOTO, Mayuko 31 March 2009 (has links)
No description available.
160

The Study of Preservice Teachers Reflection:A Case Study of Classroom Management Course

Cheng, Wen-Chun 12 February 2003 (has links)
The purpose of this research will be (1) to explore the preservice teachers¡¦ understanding of issues in classroom management; (2) to investigate the impact of asynchronous online discussion on preservice teachers¡¦ learning about classroom management; (3) to investigate the relationship between preservice teachers¡¦ reflections, worksheet and asynchronous online discussions; (4) to analyze preservice teachers¡¦ opinions about incorporating asynchronous network system into their classroom and teaching. The participants of this study come from 56 preservice teachers taking Classroom Management Course in NSYSU Teacher Education Program. The Classroom Management Course requires teaching practicum as well as encourages preservice teachers to participate in SCTnet, which is an online professional community for teachers. They can interact, discuss and share experiences online. This 18-week course includes a series of activities such as seminar discussion, interviewing intern and expert teachers, assignment, small group activities in the classroom and asynchronous online discussion. The course aims to integrate theory and practice and to develop preservice teachers¡¦ professional competences in teaching and their classroom management skills. Qualitative research methods were implemented to conduct these studies. The data collection includes assignments, comments of asynchronous discussion board, interviews and questionnaires. Document analysis is used to explore preservice teachers¡¦ interpretation of classroom management knowledge and reflection. This study reaches the following five conclusions: 1. It is a progressive process that preservice teachers understand classroom management issues with the help of course instructor and assignments. 2.The course instructor initiated and leaded discussions in asynchronous discussion board. As time goes by, preservice teachers can actively propose issues for discussion and make statements. Through dialogues, preservice teachers better understand classroom management issues. 3. Due to the lack of practical experiences in teaching, there are over 50% of preservice teachers whose reflection of assignment stagnates no-reflection level. 4. Preservice teachers¡¦ reflection level is influenced by their involvement level in learning, information use behavior and the types of discussion topics in asynchronous discussion board. 5. Most preservice teachers feel satisfied with Classroom Management course and the instructor¡¦s teaching method. In addition, based on the above conclusions, the author proposes recommendations on teacher education curriculum, preservice teachers¡¦ reflection and issues for future research.

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