This report is a product of Bachelor Degree Project at Mechanical Engineering department inLinnaeus University, Växjö, Sweden. The project is about a design improvement of industrialcompact mixers.This project is accomplished with Xylem, one of the main suppliers of compact mixers in theindustry, located at Emmaboda, Sweden. The company has a problem with the existing designof the two part, oil housing and entrance cover, in 4610/20 compact mixers. The 4610/20compact mixers has suffered from quality problems which affect the production and the endcustomer because of the existing design of these part. The aim of this study is to improve thequality of the product by redesigning of oil housing and entrance cover. In addition to theredesigning of these parts, another important purpose of the project is to produce these partsfrom different material than existing one.The computer aided design programs are widely used, Solid Works, during the project. Forselection of a new material a wide literature research has been accomplished.

The role of remote sensing data for monitoring different parameters in the study of ecosystems has been increasing. Particularly the development of different indices has played a great role to study the properties of vegetation and vegetation dynamics in large countries. In addition to this, satellite rainfall estimate data has been used to study the pattern of precipitation in areas where station rain-gauge data is not available. The Normalized Difference Vegetation Index (NDVI) and rainfall estimates data from the National Oceanic and Atmospheric Administration (NOAA) satellites were used to investigate the spatio-tempotal pattern of precipitation and the response of vegetation to precipitation in Ethiopia from 1996 to 2008. The patterns were studied in different land cover classes using data from the Global Land Cover Network (GLCN). The spatial patternof NDVI and precipitation showed that vegetation responded directly to precipitation. The seasonal patterns showed that there was between 0 to 3 months lag between precipitationand vegetation. However it was not possible to draw conclusion regarding the annual trendsof precipitation and NDVI because of the nature of the NDVI data, which was produced using the 10 day maximum composite values.

The potential of atmospheric dust aerosols to modify the Earth's environment and climate has been recognized for some time. However, predicting the diverse impact of dust has several significant challenges. One is to quantify the complex spatial and temporal variability of dust burden in the atmosphere. Another is to quantify the fraction of dust originating from human-made sources. This thesis focuses on the spatiotemporal characterization of sources and dust outbreaks in Central and East Asia by integrating ground-based data, satellite multi-sensor observations, and modeling. A new regional dust modeling system capable of operating over a span of scales was developed. The modeling system consists of a dust module DuMo, which incorporates several dust emission schemes of different complexity, and the PSU/NCAR mesoscale model MM5, which offers a variety of physical parameterizations and flexible nesting capability. The modeling system was used to perform for the first time a comprehensive study of the timing, duration, and intensity of individual dust events in Central and East Asia. Determining the uncertainties caused by the choice of model physics, especially the boundary layer parameterization, and the dust production scheme was the focus of our study. Implications to assessments of the anthropogenic dust fraction in these regions were also addressed. Focusing on Spring 2001, an analysis of routine surface meteorological observations and satellite multi-sensor data was carried out in conjunction with modeling to determine the extent to which to this integrated data set can be used to characterize the spatiotemporal distribution of dust plumes at a range of temporal scales, addressing the active dust sources in China and Mongolia, mid-range transport and trans-Pacific, long-range transport of dust outbreaks on a case-by-case basis. This work demonstrates that adequate and consistent characterization of individual dust events is central to establishing a reliable climatology, ultimately leading to improved assessments of dust impacts on the environment and climate. This will also help to identify the appropriate temporal and spatial scales for adequate intercomparison between model results and observational data as well as for developing an integrated analysis methodology for dust studies.

Accurate areal measurements of snow-cover extent are important for hydrological and climate modeling. The traditional method of mapping snow cover is binary where a pixel is approximated to either snow-covered or snow-free. Fractional snow cover (FSC) mapping achieves a more precise estimate of areal snow-cover extent by determining the fraction of a pixel that is snow-covered. The two most common FSC methods using Moderate Resolution Imaging Spectroradiometer (MODIS) images are linear spectral unmixing and the empirical Normalized Difference Snow Index (NDSI) method. Machine learning is an alternative to these approaches for estimating FSC, as Artificial Neural Networks (ANNs) have been used for estimating the subpixel abundances of other surfaces. The advantages of ANNs over the other approaches are that they can easily incorporate auxiliary information such as land-cover type and are capable of learning nonlinear relationships between surface reflectance and snow fraction. ANNs are especially applicable to mapping snow-cover extent in forested areas where spatial mixing of surface components is nonlinear. This study developed an ANN approach to snow-fraction mapping. A feed-forward ANN was trained with backpropagation to estimate FSC from MODIS surface reflectance, NDSI, Normalized Difference Vegetation Index (NDVI) and land cover as inputs. The ANN was trained and validated with high spatial-resolution FSC derived from Landsat Enhanced Thematic Mapper Plus (ETM+) binary snow-cover maps. ANN achieved best result in terms of extent of snow-covered area over evergreen forests, where the extent of snow cover was slightly overestimated. Scatter plot graphs of the ANN and reference FSC showed that the neural network tended to underestimate snow fraction in high FSC and overestimate it in low FSC. The developed ANN compared favorably to the standard MODIS FSC product with the two methods estimating the same amount of total snow-covered area in the test scenes.

The Corredor Bioceanico is a major transportation project connecting the agricultural heartlands of South America to the Atlantic and Pacific coasts. The final link is in southeastern Bolivia - an underdeveloped area that is home to two indigenous groups and globally-significant woodlands and wetlands. Infrastructure developments - comprising a major highway upgrade, revitalized railway services and increased flows along gas pipelines to Brazil - pose major threats to livelihoods and the region's ecological integrity. There are two broad objectives: (i) to map and quantify the spatial patterns of land change using a time-series of coarse and medium resolution satellite imagery; and (ii) to understand the socio-economic and political drivers of change by linking household surveys and interviews with farmers; environmental, climatic, and political data; and classified satellite imagery. Overall, large-scale deforestation has occurred along the Corredor Bioceanico for mechanized commercial production of oil-seed crops such as soybeans and sunflower. The significance of these findings is that agriculture-driven deforestation is pushing into sensitive areas threatening world-renowned ecosystems such as the Chaco, Chiquitano and Pantanal as well as noteworthy national parks. Though quantity remains relatively small compared to other parts of South America, rates of forest loss match or exceed those of more publicized regions such as Rondonia or Mato Grosso, Brazil. Moreover, rates of forest loss are accelerating linearly with time due to policies implemented by incumbent president Evo Morales. Results also show that in the first years of cultivation, pasture is the dominant land-use, but it quickly gives way to intensively cropped farmland. The main findings in terms of percentage area cleared according to forest type is that farmers appear to be favoring transitional forest types on deep and poorly drained soils of alluvial plains. Semi-structured interviews with farmers and representatives of key institutions illustrate that price determined by the global market is not proportionally the most dominant motive driving LULCC in the lowlands of Santa Cruz, Bolivia - an area seen as a quintessential neoliberal frontier.

Changes with land cover and land use are closely integrated with water and other ecological processes at the land surface. Nowhere is that more apparent than in the Edwards Aquifer region of southcentral Texas. The Edwards Aquifer contributing and recharge zones cover approximately 18,000 square kilometers in parts of 15 counties in Texas and includes San Antonio and Austin, the nation's eighth and nineteenth largest cities, respectively. Population growth within the counties that intersect the Edwards Aquifer contributing and recharge zones has taken place over the last two decades, with the logical translation being an expanded infrastructure. This implies that a greater amount of impervious surface coverage and other land cover changes have occurred. This work quantified the changes in land cover within the Edwards Aquifer contributing and recharge zones between the years 1986 and 2000. Increasing trends in impervious surface area and woodland growth were identified. Additionally, a new ArcView software tool was developed to process SSURGO soil data for use within the ArcView SWAT model. Hydrologic modeling for the Upper Sabinal River watershed, located within the Edwards Aquifer region, revealed that the high resolution SSURGO data produces different results when used in place of the existing STATSGO soils data. Finally, an index of urbanization was developed and evaluated to assist investigators in identifying potential areas of urbanization.

Thesis (M.S.)--California Polytechnic State University, 2009. / Title from PDF title page; viewed on December 2, 2009. Major professor: Brent G. Hallock, Ph.D. "Presented to the faculty of California Polytechnic State University, San Luis Obispo." "In partial fulfillment of the requirements for the degree [of] Master of Science in Agriculture with specialization in Soil Science." "November 2009." Includes bibliographical references (p. 67-71). Also available on microfiche.

Dramatic land-cover changes have occurred in a broad range of spatial and temporal scales over the last decades. Satellite remote sensing, which can observe the earth's surface in a consistent manner, has been playing an important role in monitoring and evaluating land-cover changes. Meanwhile, optical remote sensing, a common approach to acquiring land-cover information, is limited by weather conditions and thus is greatly constrained in areas with frequent cloud cover and rainfall. Recent advances in polarimetric SAR (PolSAR) provide a promising means to extract timely information of land-cover changes regardless of weather conditions. SAR satellite can pass through an area from different orbits, namely ascending orbit and descending orbit. The PolSAR images from the same orbit will have similar backscattering even with different incident angles. But if images are acquired from different orbits, the backscattering will vary greatly, which causes many difficulties to land cover change detection. The proposed algorithms in this study can perform land cover change detection in three situations: 1) repeat-pass images (image from the same orbit and with same incident angle, 2) images from the same orbit but with different incident angle, and 3) images from different orbits. Using images from different orbits will largely reduce the monitoring interval which is important in the surveillance of natural disasters. The present study proposes 1) a sub-pixel automatic registration technique, 2) an automatic change detection technique and 3) an iterative framework to process a time series of PolSAR images that can be applied to the PolSAR images from different orbits. Firstly, automatic registration is crucial to the change detection task because a small positional error will largely degrade the accuracy of change detection. The automatic registration technique is based on the multi-scale Harris corner detector. To improve the efficiency and robustness, the orientation angle differencing method is proposed to reject outliers. This differencing method has been proved effective even in the experiment of using PolSAR images from different orbits when less than 5% of the feature point matches are correct. Secondly, the change detection technique can automatically detect land-cover conversions and classify the newly input image. Hierarchical segmentation has been applied in the change detection which generates objects within the constraint of the previous classification map. Multivariate kernel density estimation is applied to classify newly input PolSAR image. The experiments show that the proposed change detection technique can mitigate the effect of polarimetric orientation shift when the PolSAR images are from different orbits, and it can achieve high accuracy even when complex local deformation is appeared. Lastly, the iterative framework, which integrates the automatic registration and automatic change detection techniques, is proposed to process a time series of PolSAR images. In the iterative process, no obvious decrease of classification accuracy is observed. Therefore, the proposed framework provides a potential treatment to derive land-cover dynamics from a time series of PolSAR images from different orbits. / published_or_final_version / Urban Planning and Design / Doctoral / Doctor of Philosophy

Sliding failures of landfill cover systems are common, and the slip surface is often at the interface between a geosynthetic drainage layer and an underlying textured geomembrane. In an effort to understand the sliding failures, the objectives of this research project are to summarize current regulation and practice in landfill cover design, use experimental methods to characterize the behavior of geosynthetic landfill materials in cover systems approaching failure, and develop models to evaluate the hydraulic performance and stability of landfill cover systems. Inclined plane tests were conducted to explore the behavior of a geosynthetic drainage material/textured geomembrane interface. The interface had effective normal stress dependent strain softening behavior, with more strain softening measured at higher effective normal stresses. A numerical model for confined flow in a drainage layer with a constrained outlet was developed. The model was used to evaluate how water fills and empties from a geosynthetic drainage layer for a variety of inflow conditions and constraints to flow at the outlet. The model was used to demonstrate that a drainage layer that effectively conveys water out of a cover system with a free flowing drainage outlet quickly fills with water when the outlet has a modest constraint to flow. An iterative, numerical model was developed to calculate stability solutions for landfill cover slopes that satisfy force equilibrium and strain compatibility while accounting for effective normal stress dependent strain softening and various pore water pressure conditions. Stability solutions reveal that depending on the water pressure in the drainage layer, the geosynthetic drainage material may experience tension at many points along the slope. It is crucial for the stability of the landfill cover system to maintain free-flowing conditions at the drainage layer outlet. A modest constraint to flow at the outlet has a significant adverse effect on the ability of the landfill cover drainage layer to convey water out of the system, which can lead to instability. The drainage layer outlet should be designed to ensure free flow of water out of the drainage layer. / text

Mining operations lead to considerable land disturbance and accumulation of large amounts of waste rock that may contain elevated concentrations of hazardous substances. Without proper capping, they may have considerable negative environmental impact on different spheres of the Earth. Capping of waste rock with a soil cover re-creates the water and nutrient regimes required for the growth of native plants and returns biological productivity and biodiversity of the land to a condition similar to that existing before site disturbance. In many cases the area of disturbance is composed of coarse-textured materials with low water retention properties, which are not desirable in semi-arid zones. This study was conducted to determine (1) whether a considerable increase of water storage is possible after separation of coarse-textured soil into size fractions and layering them in such a way that the finer fraction overlies the coarser fraction; and (2) whether such soil covers are susceptible to preferential flow under various initial and boundary conditions and what influence this type of flow has on residence time. Four types of soil covers were constructed in chambers: homogeneous covers composed of natural sand, two-layered covers with abrupt and gradual interlayer transitions, and four layered soil covers with abrupt transitions. Soil water storage was measured at field capacity (FC). Soil covers were tested under two types of lower boundary conditions: gravel layer and -25-cm matric potential. Flow stability was assessed during intermittent and constant ponded infiltrations. Water storage capacities (WSCs) for soil covers with -25-cm matric potential at the bottom of a cover were additionally simulated in HYDRUS-1D. Water storage capacities increased with the number of layers under both lower boundary conditions. Two-layered covers with a transition layer had slightly lower water storage than the same cover without the transition, due to a decreased hydraulic contrast at the layer interface. Simulated WSCs under -25-cm matric potential at the bottom were in satisfactory agreement with measured WSCs. The wetting front was stable in the homogeneous cover under both initially dry and FC conditions and in the two-layered cover with a gradual transition under initially dry water content during intermittent ponded infiltration. Unstable flow was observed only in the two-layered soil cover under both initial water contents. Other covers were partially unstable under initially air-dry and FC conditions. Generally, the wetting front was more diffuse at FC. Flow in all covers was stable under constant ponded infiltration. The residence time of water increased with the increase in the number of layers under both types of infiltration. Results of the study show that WSC and residence time do increase with increasing number of layers in soil covers, where layers are composed of different fractions of coarse-textured soil. In addition, tested soil covers have shown limited susceptibility to preferential flow even when layered into finer-over-coarser soil systems.