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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Physical and Geochemical Characterization of Two Wetlands in the Experimental Lakes Area, North-western Ontario, Canada

Anderson, Miles 24 September 2012 (has links)
Anthropogenic disruptions in the form of hydrological alterations, such as dam construction and the associated water diversions are a cause of much upheaval to local and regional ecosystems. Lake 626 within the Experimental Lakes Area of north-west Ontario, along with its downstream wetlands, 626A and 626B are one such system. Construction of a dam at the L626 inflow has completely restricted water flow, reducing and reshaping the watershed, increasing water retention time, and decreasing outflow into the wetlands. This study investigates the state of each wetland through physical and geochemical characterization during the first year following the diversion. Previous studies have found that hydrological diversions in wetlands can lower water table levels, altering soil chemistry and producing a shift in floral and faunal communities. Ultimate consequences involve significant loss of wetland area through conversion to upland habitat. This provides a model for climatic warming scenarios, wherein sustained drought conditions can produce the same result. Boreal wetlands are surprising fragile ecosystems that store massive quantities of carbon and are at risk of releasing it in such situations. One study showed that an extended summer drought in an otherwise average year with above average precipitation produced losses of 90 g C/m2 over the course of the year. Maintenance of reduced-flow in wetlands 626A and 626B is expected to convert the system into a carbon source and reduce overall wetland area. Radiocarbon dating has revealed that following deglaciation, both 626A and 626B basins were open water wetlands, depositing limnic peat for about 3200 and 1300 years respectively. Each site then transitioned into open sedge dominated fen – 626B to the present and 626A until about 2.5 ka BP when Sphagnum began to develop. Wetland 626B is decidedly an open shrub/sedge fen, supporting Myrica gale, Chamaedaphne calyculata and Carex rostrata / lasiocarpa communities. Wetland 626A is a bog/fen complex, sharing similar communities in the fen areas, but housing a large, centrally located bog of shrub species overlying Sphagnum hummocks. Tritium values in 626A were similar to cosmic background levels, indicating that recharge of basal pore water has not occurred in at least 60 years. Tritium in 626B was much higher, suggesting a substantial difference in hydrology or peat hydraulic conductivity between the basins. Measurement of DOC profiles showed high concentrations in near-surface water, reaching over 80 mg/L, and dropping to about 20 mg/L at maximum depths. An opposite trend was seen for DIC and CH4 profiles which increased concentration with depth (25 – 70 mg/L DIC; 75 – 700 μmol/L CH4). Isotopically however, 13C signatures from basal DIC were more positive while signatures from CH4 were typically more negative (-6 ‰ to +4 ‰ DIC; -57 ‰ to -73 ‰ CH4). Breakdown of DOC by LC-OCD showed high concentrations of humic substances and low molecular weight neutrals. The origin of humic substances in surface water became more pedogenic with increasing distance from the L626 outflow, indicating the influence of decaying wetland vegetation on the DOC of adjacent water. A comparison between contemporary and future characterization of boreal peatlands under drought-like conditions will provide a better understanding of the impacts suffered by wetlands during hydrological alterations. The high sensitivity of wetlands to changing hydrology should also provide a measure for gauging the effects of long term climate warming. This will assist in the development of environmental policies to better govern both the establishment of water diversions and the multitude of other practices leading to climate change.
22

Investigation on Electrical Analysis and Physics Mechanism of Low Temperature Polycrystalline-silicon Thin Film Transistor

Huang, Sung-yu 20 July 2006 (has links)
There were three poly-Si TFT made by ELA, SLS, and HREC. The HREC TFT had better reliability than ELA TFT and SLS TFT under AC and hot carrier stress. And the effect of bending in SLS TFT was more obvious then ELA TFT, it provide us a better choose to develop a flexible TFT LCD. In poly-Si TFT, the photon current would decrease if there was a grain boundary in the channel. In all parameters include both manufacture and measurement the HREC TFT had better behaviors than ELA TFT and SLS TFT. But there also some shortcomings we must overcome include we muse growth a heat-retaining layer extra and must etch it and the poly-Si/heat-retaining etch rate and so on.
23

Physical and Geochemical Characterization of Two Wetlands in the Experimental Lakes Area, North-western Ontario, Canada

Anderson, Miles 24 September 2012 (has links)
Anthropogenic disruptions in the form of hydrological alterations, such as dam construction and the associated water diversions are a cause of much upheaval to local and regional ecosystems. Lake 626 within the Experimental Lakes Area of north-west Ontario, along with its downstream wetlands, 626A and 626B are one such system. Construction of a dam at the L626 inflow has completely restricted water flow, reducing and reshaping the watershed, increasing water retention time, and decreasing outflow into the wetlands. This study investigates the state of each wetland through physical and geochemical characterization during the first year following the diversion. Previous studies have found that hydrological diversions in wetlands can lower water table levels, altering soil chemistry and producing a shift in floral and faunal communities. Ultimate consequences involve significant loss of wetland area through conversion to upland habitat. This provides a model for climatic warming scenarios, wherein sustained drought conditions can produce the same result. Boreal wetlands are surprising fragile ecosystems that store massive quantities of carbon and are at risk of releasing it in such situations. One study showed that an extended summer drought in an otherwise average year with above average precipitation produced losses of 90 g C/m2 over the course of the year. Maintenance of reduced-flow in wetlands 626A and 626B is expected to convert the system into a carbon source and reduce overall wetland area. Radiocarbon dating has revealed that following deglaciation, both 626A and 626B basins were open water wetlands, depositing limnic peat for about 3200 and 1300 years respectively. Each site then transitioned into open sedge dominated fen – 626B to the present and 626A until about 2.5 ka BP when Sphagnum began to develop. Wetland 626B is decidedly an open shrub/sedge fen, supporting Myrica gale, Chamaedaphne calyculata and Carex rostrata / lasiocarpa communities. Wetland 626A is a bog/fen complex, sharing similar communities in the fen areas, but housing a large, centrally located bog of shrub species overlying Sphagnum hummocks. Tritium values in 626A were similar to cosmic background levels, indicating that recharge of basal pore water has not occurred in at least 60 years. Tritium in 626B was much higher, suggesting a substantial difference in hydrology or peat hydraulic conductivity between the basins. Measurement of DOC profiles showed high concentrations in near-surface water, reaching over 80 mg/L, and dropping to about 20 mg/L at maximum depths. An opposite trend was seen for DIC and CH4 profiles which increased concentration with depth (25 – 70 mg/L DIC; 75 – 700 μmol/L CH4). Isotopically however, 13C signatures from basal DIC were more positive while signatures from CH4 were typically more negative (-6 ‰ to +4 ‰ DIC; -57 ‰ to -73 ‰ CH4). Breakdown of DOC by LC-OCD showed high concentrations of humic substances and low molecular weight neutrals. The origin of humic substances in surface water became more pedogenic with increasing distance from the L626 outflow, indicating the influence of decaying wetland vegetation on the DOC of adjacent water. A comparison between contemporary and future characterization of boreal peatlands under drought-like conditions will provide a better understanding of the impacts suffered by wetlands during hydrological alterations. The high sensitivity of wetlands to changing hydrology should also provide a measure for gauging the effects of long term climate warming. This will assist in the development of environmental policies to better govern both the establishment of water diversions and the multitude of other practices leading to climate change.
24

Accumulation Area Ratio and Equilibrium Line Altitude on the Southern Patagonia Icefield, 2000 - 2010, retrieved using MODIS satellite images

Peterson, Gustaf January 2010 (has links)
Estimations of accumulation area ratio (AAR) and equilibrium line altitude (ELA) were carried out on the Southern Patagonia Icefield. The icefield lies on the border between Chile and Argentina on the southern tip of South America. It is the largest mid-latitude ice mass in the world but despite this fact little research has been conducted in the area. The main reasons for this are most likely the harsh weather conditions and remoteness of the area. However, since icefield’s act as a source for fresh water and as an indicator of climate change more research is crucial. This study focuses on three objectives: to map the snow cover, to estimate AAR and ELA and to discuss their variations during the period 2000 to 2010. The Moderate Resolution Imaging Spectroradiometer (MODIS) is particularly useful for studying cloudy areas because it’s high temporal resolution increase the chances of acquiring cloud- free images. Satellite images were processed, classified and analyzed. The classification results yielded large interannual variations but also congruity. The pattern of the snow cover suggest substantial wind control on snow accumulation, particularly snow deposition on eastern slopes. No statistically significant trends of AAR and ELA could be detected, although, a vague decrease in AAR and increase in ELA is recognized. Average values of AAR and ELA estimated over the period yields lower AARs and higher ELAs than previously suggested. The average AAR is calculated to be 0.66. Average ELA is estimated to be 970 m.a.s.l. and 1270 m.a.s.l. for the western and eastern sides, respectively.
25

Providing Meaningful Grade Aligned ELA to All

Mims, Pamela J. 21 April 2018 (has links)
Students with intellectual disabilities and autism have been underexposed to grade aligned English/Language Arts (ELA) content, including literacy. This session highlights research to guide participants’ practice in implementing meaningful grade aligned ELA content such as vocabulary, opinion writing, comprehension of fiction and nonfiction text, and student led research for students with low incidence disabilities. A presentation of evidence-based practices such as the use of technology, grade aligned adapted fiction and nonfiction text, and systematic instruction will be featured, as well as ways to promote personalized learning in the classroom.
26

Sound and Waves: An Integrated K–8 Hands‐On Approach Supporting the NGSS and CCSS ELA

Tai, Chih-Che, Keith, Karin, Robertson, Laura, Moran, Renee Rice 01 April 2017 (has links)
Receive practical ideas to build understanding about how to combine reading and hands-on activities as tools to understand the nature of wave movement.
27

Third grade students' home computer access and their proficiency on standardized English Language Arts assessment

Schaeffer, Mary Kristine 02 November 2021 (has links)
No description available.
28

Zjišťování změn polohy ELA ledovců v pohoří Cordillera Blanca, Peru, z dat DPZ / Detection of Equilibrium Line Altitude (ELA) Changes from Remote Sensing Data; Case Study from the Cordillera Blanca, Peru

Paraj, Zsolt January 2015 (has links)
The aim of this diploma thesis is to monitor glacier change in the Cordillera Blanca in the period from 1987 to 2014. This diploma thesis focuses on three mountains and eleven glaciers in the northern part of the Cordillera Blanca. The input data consist of 29 Landsat scenes (Landsat 4,5,7 and 8) and the ASTER global digital elevation model version 2. Semi-automatic classification algorithm is created based on threshold values detected by spectral analyses of selected land cover types in the Cordillera Blanca. Additionally, the mean snowline (equilibrium line) altitude change is computed for all of the three mountains and eleven glaciers. Besides, glacier change depending on slope and aspect is evaluated. The results of this diploma thesis are presented in maps, tables and charts. The results of the classification are compared with the GLIMS Glacier Database and the field measurements provided by Adam Emmer, MSc. Finally, the advantages and disadvantages of the new Landsat 8 satellite sensor are discussed. Key words: Remote sensing, Landsat, classification, ice and snow detection, ELA, Cordillera Blanca
29

アニール技術を用いた高性能シリコン薄膜トランジスタに関する研究 / アニール ギジュツ オ モチイタ コウセイノウ シリコン ハクマク トランジスタ 二カンスル ケンキュウ

野口 隆, Takashi Noguchi 28 February 1992 (has links)
ポリSi薄膜トランジスタ(TFT)の高性能化について、理論的、技術的な観点から種々の問題点を導き、特にトラップ密度や粒径の大小がTFTの電気的特性に与える影響を詳細に解析し、イオン注入やその後のアニール技術などによって充分に実証を行ったものである。特にエキシマレーザアニール(ELA)を用いた、全工程が下地に影響を与えない低温プロセスは、LSIの微細化とガラス上素子特性の向上に資するものとして有益な知見と考えられる。 / 博士(工学) / Doctor of Philosophy in Engineering / 同志社大学 / Doshisha University
30

Creating a Sentence Frame Toolkit Based on Third Grade Writing Standards to Support the Writing Instruction of Spanish-Speaking English Learners

Rosa Le Bron, Tanisha J 01 January 2020 (has links)
Third grade general education teachers, particularly in Florida, will teach English learners (ELs) in their classroom who must participate in their English Language Arts writing classes at roughly the same pace as native English speakers in order to perform grade-level, standards-based writing tasks. For this reason, general education teachers must be equipped with helpful, research-based resources to support the ELs to become equally successful in writing instruction as their native-speaking peers. This thesis explored the use of sentence frames for improving the English skills of ELs as they start to understand and use the syntax of Standard English. As a result, this thesis created a teacher-friendly resource, the Sentence Frame Toolkit for Third Grade, containing sentence frame templates and sample student work for third grade teachers to use as a resource when teaching expository writing in English Language Arts to Spanish-speaking ELs. The sentence frames in the toolkit are aligned to Florida’s third grade expository writing standards from Cluster I. By using the sentence frames in the toolkit as support, ELs will be able to turn thoughts into words, produce the second language at their pace, and continue to improve as skilled writers.

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