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LONG-TERM EFFECTS OF SUBSURFACE DRAIN SPACING ON SOIL PHYSICAL AND CHEMICAL PROPERTIESKevin Samuel Mitchell (9173993) 27 July 2020 (has links)
<p><a>Subsurface tile drainage is a
commonly used practice to lower the water table in poorly drained soils, and is
often done to improve soil conditions for agricultural operations. Tile drainage
has been shown to increase cash crop yield, allow for more timely field
operations, and reduce erosion.</a> However, few studies have evaluated the potential long-term
changes in soil physical and chemical properties as a result of subsurface tile
drainage. This study was conducted on a naturally poorly drained Clermont silt
loam soil located at the Southeast Purdue Ag Center near Butlerville Indiana.
The intent of this study was to characterize possible evolution of soil
physical and chemical properties after 35 years of subsurface drainage. <a>The field site was established in the spring of 1983 with
tile drains installed in 2 blocks with tile spacings of 5, 10, 20, and 40m, with the 40-m spacing used
as the undrained control</a>. Soil samples were collected in May of 2018 to a
depth of 1 meter and were analyzed for carbon and nitrogen content, aggregate
stability, and fertility at depth increments of 0-5, 5-15, 15-30, 30-50, 50-75
and 75-100cm. In-field measurements were also taken in May of 2018 for vane
shear resistance and in May of 2019 for cone penetration resistance. Total
carbon content was found to be significantly higher in the 5-m tile spacing
than the 40-m tile spacing in the 0-5cm and 5-15cm depths, with the 10-m and
20-m tile spacings being intermediate. Conversely, in the 75-100cm depth the
inverse trend was observed, where the 40-m tile spacing was found to have
significantly greater carbon content than narrower tile spacings. Trends
observed with carbon stocks per depth increment closely followed trends
observed with carbon content at the same depth. However, no significant
differences were observed among treatments with the summation of carbon stocks
to the 1-m depth. Tile spacing did not have a significant effect on aggregate
stability at any depth. The soil fertility data showed some indication of the
potential translocation of soil calcium from the soil surface to lower depths
in the soil profile resulting in significantly higher soil pH in the 5-m tile
spacing than the 40-m tile spacing in all depths below 30cm. No consistent
differences related to treatment were found with the cone penetrometer or vane
shear penetrometer measurements. After 35 years of drainage history, tile drain
spacing did not have a significant effect on total carbon stocks to the 1-m
depth, but rather seems to have had a significant effect on the vertical
distribution of soil carbon content throughout the soil profile.</p>
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Investigation of materials based on pulverized fuel ash and sodium silicate solutionsSalem, Mahmoud January 1991 (has links)
No description available.
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A scientific investigation of the brick and tile industry of York in the mid-eighteenth centuryBetts, Ian M. January 1985 (has links)
Petrological and neutron activation analysis of bricks and tiles from York and neighbouring sites with discussion of the analytical and documentary evidence for their production in York up until AD 1750.
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A scientific investigation of the brick and tile industry of York in the mid-eighteenth centuryBetts, Ian Michael January 1985 (has links)
Petrological and neutron activation analysis of bricks and tiles from York and neighbouring sites with discussion of the analytical and documentary evidence for their production in York up until AD 1750.
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Evaluating the Performance of Denitrifying Bioreactors for Removal of Agricultural Nitrate from Tile-Drainage EffluentFlemming, Corey January 2016 (has links)
The application of nitrogen (N) fertilizers and manure to agricultural soil is essential for crop production, but has in turn introduced environmental impacts including: eutrophication, contamination of groundwater, freshwater acidification, and an increase in greenhouse gas emissions. The movement of nitrogen was observed following liquid swine manure applications at six fields in Winchester, ON employing controlled tile drainage and denitrifying bioreactors. The manure was mainly in the form of ammonium during application where it was transformed to other N species including nitrate and nitrous oxide (N2O) by microbial activity in soil. Large soil N2O fluxes occurred in fields throughout 2012 and 2013, and total N of soil in the fields was enriched in 15N, indicating denitrification. Soil nitrate was also leached and collected by drainage tiles, and a portion of the tile water was treated by denitrifying bioreactors. Previous studies have demonstrated that denitrification of nitrate in bioreactors elicits the production of N2O, which is emitted from the overlying soil surface and/or is released as dissolved N2O in tile effluent. In this study, it is found that a decrease in nitrate was associated with decreasing levels of nitrous oxide during a rain event, and no significant N2O flux was recorded above bioreactors throughout either year. The δ15N and δ18O signatures of nitrate did not change significantly following bioreactor treatment and did not exhibit the 15N and 18O enrichment that is characteristic of denitrification. The data demonstrates that the decrease in nitrate through the bioreactors was due to dilution, likely from the accumulation of rainfall in reactor beds employing controlled tile drainage. Further work is needed to examine the conditions under which dilution may occur in place of denitrification.
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An Automated Method of Identifying the Location of Agricultural Field Drainage Tiles in Northwest OhioReynolds, Elaine P. January 2014 (has links)
No description available.
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Les producteurs de matériaux de construction en terre cuite et d'amphores en Gaule Narbonnaise : l'apport des estampilles à la connaissance des structures socio-économiques d'une province romaine (fin Ier s. av. - fin IIIème s. ap.) / The producers of clay building materials and amphoras in Gallia Narbonensis : the contribution of the stamps to the knowledge of socio-economics structures of a Roman Province(end of 1st century BC - end of 3rd century AD)Corbeel, Séverine 06 December 2018 (has links)
La valeur et le caractère informatif des inscriptions présentes sur l’instrumentum domesticum ont véritablement été appréhendés pour la première fois à partir de la fin du XIXe siècle, notamment grâce aux travaux pionniers d’Heinrich Dressel sur briques, tuiles et amphores découvertes à Rome. Pour la province de Gaule Narbonnaise, il a fallu attendre près de cent ans, avec la publication de la thèse de Fanette Laubenheimer sur les amphores gauloises, ce qui a permis de répertorier des graffiti et des tituli picti, mais surtout de regrouper un corpus de 289 estampilles, soit 61 timbres distincts. Les premiers recueils de timbres sur matériaux de construction en terre cuite sont des travaux de collectes et d’inventaires réalisés à une échelle régionale ou micro-régionale, également dans les années 1980.Cette thèse s’inscrit dans la continuité de ces recherches. Elle présente deux catalogues. Le premier concerne les matériaux de construction en terre cuite avec 3183 timbres correspondant à 241 estampilles distinctes. Et le deuxième, les amphores gauloises et les couvercles de celles-ci, avec au total 941 timbres, soit 209 estampilles distinctes. Ce travail d’inventaire a été possible grâce au dépouillement de nombreuses revues, ouvrages et autres ressources bibliographiques. Les normes de cette documentation étant différentes, toutes les illustrations ont été homogénéisées afin d’être publiées à l’échelle 1/1, avec un même code couleur.La réalisation de tels corpus de timbres ouvre la porte à des études préliminaires qui apportent d’importants renseignements sur les différentes structures de productions mais aussi sur les producteurs. L’étude chronologique de la paléographie des estampilles permet d’aborder les habitudes de timbrage d’une province, à un moment donné et parfois en fonction de la zone de production. La réalisation de cartes de répartition permet d’étudier la diffusion des matériaux. Enfin, les études prosopographiques permettent d’en apprendre un peu plus sur l’identité des personnages qui apposaient leur nom sur les productions.Un des objectifs premiers de cette thèse est de fournir aux archéologues et aux historiens un outil de travail exploitable lors de la découverte de timbres sur tuiles, briques ou amphores gauloises. Nous avons également souhaité faire prendre conscience de l’intérêt de communiquer ces découvertes et de mentionner les contextes chrono-stratigraphiques, afin de pouvoir mener une réflexion socio-économique à l’échelle d’une province entière. / The value and the informative nature of the inscriptions on the instrumentum domesticum were actually understood for the first time after the end of the 19th century, thanks to the pioneering work of Heinrich Dressel on bricks, tiles and amphorae discovered in Rome. For the province of Gaule Narbonnaise, it was necessary to wait nearly one hundred years for the publication of Fanette Laubenheimer’s thesis on Gallic amphorae, which made it possible to list graffiti and tituli picti, but especially to gather a body of 289 stamps, of which 61 were distictively different. The earliest collections of stamps on terracotta building materials are collections and inventories carried out on a regional or micro-regional scale, also in the 1980s.This thesis is part of the continuity of this research. It presents two catalogs. The first concerns terracotta building materials with 3183 stamps corresponding to 241 different stamps. And the second, the Gallic amphorae and their corresponding lids, with a total of 941 stamps, of which 209 are separate stamps. This inventory work was made possible through the compilation of numerous journals, books and other bibliographic resources. The standards of this documentation being different, all the illustrations have been adapted to be published at the scale 1/1, with the same color code.The compilation of such a body of stamps opens the door to preliminary studies, thus providing important information not only on the different structures of productions, but also on the producers. The chronological study of the palaeography of the stamps makes it possible to examine the stamping habits of a province, at a given time and sometimes in relation to the production area. The creation of distribution maps makes it possible to study the diffusion of materials. Finally, prosopographic studies make it possible to learn a little more about the identity of the people who put their name on the productions.One of the primary objectives of this thesis is to provide archaeologists and historians with a workable tool that can be useful when discovering stamps on Gallic tiles, bricks or amphorae. We also wanted to raise awareness of the value of communicating these discoveries and to mention the chrono-stratigraphic contexts, in order to be able to carry out a socio-economic reflection on the scale of a whole province.
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The study of business strategies For ceramic tile industryLin, Ming-wen 24 August 2007 (has links)
Abstract
When Taiwanese ceramic tile industry invested in the Mainland China, they are facing the differences between cross-strait strategies. Shall the Taiwanese businessmen change their business management strategy? This is the subject of present study.
The objectives of present study include the following: (1) to find out the knowledge of Taiwanese ceramic tile industry regarding the cross-strait strategies and to see if there¡¦s any differences among them, (2) to find out the effects of differences in cross-strait management strategy, This study includes only Taiwanese ceramic tile industry of KwangTong and Shanghai Districts and this is the main source of our sampling and information gathering. The scope of present study is limited to the differences between cross-strait strategies, emphasizing on the social and political aspects. The principal manageable variables are:
1. differences in cross-strait strategies,
2. business strategies of Taiwanese companies,
3. management strategies.
Using the Taiwanese ceramic tile industry companies or factories who had investment in Mainland China, we study the effect of above independent variables and the interaction between them. methods used include: case study analysis, confidential analysis, main factor analysis.
1. There¡¦s significant effect for Taiwanese business on management strategies.
2. There¡¦s no significant effect for differences of cross-strait cultures on management strategies.
Also the present study had presented four new kinds of business strategies, namely:
1. Hierarchy strategies: based on the hierarchy and rules.
2. Control strategies: based oneself-discipline and managerial intervention.
3. Freedom strategies: there¡¦s free style for management.
The competitiveness is from productivity and innovation not low wages, or a valued currency.
Key words : Business strategies, Taiwan company,managment
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Design of 3D Graphic Tile-based Rendering Engine for Embedded SystemsTsai, Chung-hua 03 September 2007 (has links)
Due to the increasing demand of three-dimensional (3D) graphic applications in various consumer electronics, how to develop a low-cost 3D graphic hardware accelerator suitable for the embedded systems has become an important issue. A typical 3D graphic accelerator includes a geometry sub-system and a rendering sub-system. In this thesis a highly-efficient 3D graphic rendering intellectual property (IP) based on the tiled-based approach is proposed. An entire rendering IP consists of several modules. The main contributions of this thesis focus on the development of the setup-engine, rasterization module, and the integration of the whole modules for the rendering IP. In the design of setup engine, the thesis develops a folded arithmetic unit architecture mainly consisting of one iterative divider, three multipliers and several adders, which can finish the overall computation of the setup equations within less than 50 cycles. As for the rasterization module, this thesis develops several scan-conversion algorithms including hierarchical, fast skip, and boundary-edge test methods suitable for the tiled-based rendering process. The ordinary line drawing algorithm for the scan-line boundary search or the direct in-out test approach is not efficient for tile-based approach since the shape of triangle primitives may become irregular after tiling. Our experimental results show that the boundary-edge test can lead to the most compact design since it can transform the normal in-out test circuit for single pixel to detect two end-points of the scan-line simultaneously. In addition, the rasterization module can be divided into the scan-line and the fragment generation parts which can help the optimization and speedup of the individual part to achieve the desired overall fill-rate goal. Our simulation shows the fill-rate improvement based on this approach is around 60%. Finally, this thesis integrates all the sub-modules to the entire rendering IP core. This IP has been realized by 0.18 um technology. The total gate count is 504k. It can run up to 166 Mhz, and deliver the peak fill rate of 333M pixels/sec and 1.3G texels/sec. This IP has been highly verified, and achieves more than 95% code coverage. It has also been integrated with OPENGL ES software module, Linux operation system and geometry module, and successfully prototyped on the ARM versatile platform.
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Modelling Tile Drains Under Present and Future Climate ConditionsO'Neill, Patrick 10 December 2008 (has links)
Modelling the impact of climate change on the water from agricultural areas on a regional scale over a 40 year time period is the subject of this thesis. The Grand River watershed spans approximately 290 km with an area of approximately 6,800 km². Approximately 90% of the watershed is agricultural land some of which is tile drained. These tile drains, which cover approximately 15% of the total land of the watershed, are installed to augment field drainage. The tile drains usually outlet somewhere along the perimeter of a property; the discharge then typically moves along the surface until it discharges into a surface water body such as a river, pond, or lake.
Investigating the impact of climate change on agricultural tile drainage at a watershed scale can be achieved using modelling. The tile drains can affect both the water quality and the water quantity of a watershed. With the potential climatic changes, the storm intensity, and growing season also could change.
Spatial data for the Grand River watershed was gathered to allow for further simulation. The data for tile drained areas was added to land use/land class and soil data for the watershed to produce a map of tile drained agricultural areas.
Climate change scenarios were then simulated for each cell. Three climate change scenarios were investigated to determine the impact on tile drain discharge and the hydrological process for the watershed. The climate change
scenarios that were chosen were the A2, A1B, and the B1 scenario of the Intergovernmental Panel on Climate Change.
After the simulations were completed for the tiled areas and the results collected, the simulations showed the greatest impact of tile drain discharge in the spring season as well as the fall season.
For the tiled cells the annual average discharge was approximately 0.22 m3/ha for 1999. The average discharge was approximately 0.15 m3/ha for April of 1999. April accounted for approximately 65% of the annual tile drainage for 1999.
The climate change scenarios were simulated and the average annual discharge increased approximately 0.023 m3/ha and 0.021 m3/ha for the A2 and A1B scenarios respectively. The B1 scenario had an average annual decrease of approximately 0.022 m3/ha.
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