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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

Areal and Temporal Variations in Developmental Phases of Syringa vulgaris L. Throughout the Western United States

Caprio, Joseph Michael 01 May 1970 (has links)
This paper presents the results of the analysis of 10 years of information 1957-1966 on three phases-- begin, peak and end bloom-- of the purple common lilac (Syringa vulgaris L.) using data recorded at approximately 1,000 locations throughout the Western Region of the United States. The pattern of geographical advance of the various bloom phases is determined by both a manual mapping procedure developed by the author and by standard statistical methods. Manually drawn isophanes for the various elevations for begin bloom phase are based entirely upon the first 5 years of record, 1957-1961. A Zones of Adjustment map to convert the 5-year equal level maps to the 10-year 1957-1966 normal is also manually drawn. Statistical analyses to ascertain the geographical pattern of advance were made for begin bloom phase for the 5-year period and for all three bloom phases for the 10-year period. Both the manual and statistical analyses indicate a very definite pattern of geographical advance of begin bloom phase of the lilac which is characterized by the Early Ridge. Statistical analyses of all three phases indicate a parallel geographical advance of the three phases with average regional time displacement of about 10 days from begin to peak bloom and 10 days between peak and end bloom. Only the eastern third of the Western Region corresponds closely with Hopkins' Bioclimatic Law. A measure of temporal variation of dates of bloom for each of all three phases indicate a parallel geographical advance of the three phases with average regional time displacement of about 10 days from begin to peak bloom and 10 days between peak and end bloom. Only the eastern third of the Western Region corresponds closely with Hopkins' Bioclimatic Law. A measure of temporal variation of dates of bloom for each of the three phases was determined by computing standard deviations for every station having at least 5 years of record. A map was drawn showing the temporal variability of begin bloom phase throughout the Western Region. Medians of standard deviations for stat ions within each state were also determined. Large differences in standard deviation prevail throughout the region with a general tendency for variability to be highest in the southeastern part of the region and lowest in northeastern areas. A comparison is made between the normal dates of occurrence of bloom phases and temperature data throughout the Western Region. This is achieved by comparing isophanal and isothermal charts and by statistical analysis of data at 360 stations where both phenological and temperature records are available. Comparison of isophanal patterns of equal-level isophanal maps and isotherms at given elevations ( or pressure lvels) on given dates indicate very similar patterns; both are characterized by the Early Ridge. Statistical Analyses of mean begin bloom dates and monthly mean maximum and minimum temperatures indicate that about 90 percent of the variance of bloom dates can be accounted for by maximum and minimum temperature measurements.
22

Nutrients and runoff in a small catchment during spring 2010

Skoog, Peter, Bodin-Sköld, Henrik January 2010 (has links)
<p>Eutrophication is an increasing problem in the Baltic Sea and is caused by an excess of nutrients in the water which are primarily transported with the runoff from cultivated land. The peninsula Vikbolandet in Östergötland is dominated by arable land and has stream outflows to the bays of Bråviken and Slätbaken. In this study five streams of Vikbolandet have been sampled during the spring flood period with the aim of connecting concentrations of nutrients in the streams with turbidity and runoff in the catchment. This analysis has then been related to the land use in the small catchment of Vadsbäcken in order to investigate the impact of land uses with areal losses of phosphorus. The results indicate that there are increasing concentrations of phosphorus downstream in the sites of Vadsbäcken and that the transported amounts of phosphorus increases with the spring flood and at a rainstorm event. It is shown that the distribution of agricultural blocks in the catchment of Vadsbäcken has a major impact on the nutrient leakage. There is a co-variation between turbidity and runoff during a rainstorm event and between particulate-bound phosphorus and runoff over time. A further aim has been to investigate possibilities for use of an easily managed, cost-effective environmental monitoring method for nutrient measurements in watercourses. Within four out of five streams at Vikbolandet there is a significant co-variation between turbidity and total phosphorus. Using field measurements of turbidity for environmental monitoring could provide a viable alternative for environmental monitoring of watercourses but will need further investigations of co-variation before being brought into use. Further, this study shows that the transport of phosphorus is underestimated in environmental monitoring</p>
23

On the Modifiable Areal Unit Problem and kernel home range analyses: the case of woodland caribou (Rangifer tarandus caribou)

Kilistoff, Kristen 10 September 2014 (has links)
There are a myriad of studies of animal habitat use that employ the notion of “home range”. Aggregated information on animal locations provide insight into a geographically discrete units that represents the use of space by an animal. Among various methods to delineate home range is the commonly used Kernel Density Estimation (KDE). The KDE method delineates home ranges based on an animal’s Utilization Distribution (UD). Specifically, a UD estimates a three-dimensional surface representing the probability or intensity of habitat use by an animal based on known locations. The choice of bandwidth (i.e., kernel radius) in KDE determines the level of smoothing and thus, ultimately circumscribes the size and shape of an animal’s home range. The bounds of interest in a home range can then be delineated using different volume contours of the UD (e.g., 95% or 50%). Habitat variables can then be assessed within the chosen UD contour(s) to ascertain selection for certain habitat characteristics. Home range analyses that utilize the KDE method, and indeed all methods of home range delineation, are subject to the Modifiable Areal Unit Problem (MAUP) whereby the changes in the scale at which data (e.g., habitat variables) are analysed can alter the outcome of statistical analyses and resulting ecological inferences. There are two components to MAUP, the scale and zoning effects. The scale effect refers to changes to the data and, consequently the outcome of analyses as a result of aggregating data to coarser spatial units of analysis. The aggregation of data can result in a loss of fine-scale detail as well as change the observed spatial patterns. The zone effect refers to how, when holding scale constant, the delineation of areal units in space can alter data values and ultimately the results of analyses. For example, habitat features captured within 1km2 gridded sampling units may change if instead 1km2 hexagon units are used. This thesis holds there are three “modifiable” factors in home range analyses that render it subject to the MAUP. The first two relate specifically to the use of the KDE method namely, the choice of bandwidth and UD contour. The third is the grain (e.g., resolution) by which habitat variables are aggregated, which applies to KDE but also more broadly to other quantitative methods of home range delineation In the following chapters we examine the changes in values of elevation and slope that result from changes to KDE bandwidth (Chapter 2) UD contour (Chapter 3) and DEM resolution (Chapter 4). In each chapter we also examine how the observed effects of altering each individual parameter of scale (e.g., bandwidth) changes when different scales of the other two parameters are considered (e.g., contour and resolution). We expected that the scale of each parameter examined would change the observed effect of other parameters. For example, that the homogenization of data at coarser resolutions would reduce the degree of difference in variable values between UD contours of each home range. To explore the potential effects of MAUP on home range analyses we used as model population 13 northern woodland caribou (Rangifer tarandus). We created seasonal home ranges (winter, calving, summer, rut and fall) for each caribou using three different KDE bandwidths. Within each home range we delineated four contours based on differing levels of an animal’s UD. We then calculated values of elevation and slope (mean, standard deviation and coefficient of variation) using a Digital Elevation Model (DEM) aggregated to four different resolutions within the contours of each seasonal home range. We found that each parameter of scale significantly changed the values of elevation and slope within the home ranges of the model caribou population. The magnitude as well as direction of change in slope and elevation often varied depending the specific contour or season. There was a greater decrease in the variability of elevation within the fall and winter seasons at smaller KDE bandwidths. The topographic variables were significantly different between all contours of caribou home ranges and the difference between contours were in general, significantly higher in fall and winter (elevation) or calving and summer (slope). The mean and SD of slope decreased at coarser resolutions in all caribou home ranges, whereas there was no change in elevation. We also found interactive effects of all three parameters of scale, although these were not always as direct as initially anticipated. Each parameter examined (bandwidth, contour and resolution) may potentially alter the outcome of northern woodland caribou habitat analyses. We conclude that home range analyses that utilize the KDE method may be subject to MAUP by virtue the ability to modify the spatial dimensions of the units of analysis. As such, in habitat analyses using the KDE careful consideration should be given to the choice of bandwidth, UD contour and habitat variable resolution. / Graduate / 0366 / 0329 / spicym@uvic.ca
24

Kinship terminology in the greater Hindu Kush

Ogawa, Jane January 2018 (has links)
This is a study of the kinship terminology used for one’s parents and their siblings in the languages in the greater Hindu Kush area (GHK). GHK stretches over the mountainous borderlands of Afghanistan, Pakistan, Tajikistan, China and India and homes a range of various languages from six different genera, Indo-Aryan, Iranian, Nuristani, Turkic, Tibeto-Burman, and the language isolate Burushaski. The study is based on questionnaires from native speakers of 55 language varieties collected in 2015-2017. The main distinction is one between descriptive and merging systems. The descriptive system have separate terms for all six relations and are found in the outer areas of GHK. The merging systems have terms that refer to two or more relations, and these are found in the center of the area. Within this center-area the languages are then further divided into six different terminologies depending on which relations are merged with one term. Semantic clusters can be observed, based on systematic and lexico-semantic parallels, both within and across family lines. The distribution is discussed from a historical, geographical and social point of view. / Language contact and relatedness in the Hindukush region. Vetenskapsrådet (421-2014-631)
25

Nutrients and runoff in a small catchment during spring 2010

Skoog, Peter, Bodin-Sköld, Henrik January 2010 (has links)
Eutrophication is an increasing problem in the Baltic Sea and is caused by an excess of nutrients in the water which are primarily transported with the runoff from cultivated land. The peninsula Vikbolandet in Östergötland is dominated by arable land and has stream outflows to the bays of Bråviken and Slätbaken. In this study five streams of Vikbolandet have been sampled during the spring flood period with the aim of connecting concentrations of nutrients in the streams with turbidity and runoff in the catchment. This analysis has then been related to the land use in the small catchment of Vadsbäcken in order to investigate the impact of land uses with areal losses of phosphorus. The results indicate that there are increasing concentrations of phosphorus downstream in the sites of Vadsbäcken and that the transported amounts of phosphorus increases with the spring flood and at a rainstorm event. It is shown that the distribution of agricultural blocks in the catchment of Vadsbäcken has a major impact on the nutrient leakage. There is a co-variation between turbidity and runoff during a rainstorm event and between particulate-bound phosphorus and runoff over time. A further aim has been to investigate possibilities for use of an easily managed, cost-effective environmental monitoring method for nutrient measurements in watercourses. Within four out of five streams at Vikbolandet there is a significant co-variation between turbidity and total phosphorus. Using field measurements of turbidity for environmental monitoring could provide a viable alternative for environmental monitoring of watercourses but will need further investigations of co-variation before being brought into use. Further, this study shows that the transport of phosphorus is underestimated in environmental monitoring
26

Kalibrace koherenčního rastrovacího interferometru Talysurf CCI / Calibration of Talysurf CCI coherence scanning interferometer

Varava, Anastasia January 2017 (has links)
This master’s thesis deals with calibration of a coherence scanning interferometer Talysurf CCI Lite. Basic terms related to surface texture evaluation were described along with selected profile and areal surface texture parameters. The working principle and design of the calibrated instrument were explained. Manufacturer’s calibration procedure was analyzed in relation to the definition of calibration in the International vocabulary of metrology. Further calibration steps leading to calculation of measurement uncertainty were presented. Last but not least, measurement uncertainties of areal surface texture parameters Sq and Sz were evaluated. The procedures and results described in this thesis may contribute to wider use of non-contact surface texture measuring instruments.
27

Demografiska och geografiska effekter på boendesegregationsindex : En kvantitativ studie som avser undersöka mått av boendesegregation

Johansson, Markus January 2021 (has links)
I den här uppsatsen undersöks fem olika boendesegregationsindex som används för att beräkna och skildra graden av boendesegregation i samhället. Syftet är att studera hur index påverkas av slumpmässigt genererade befolkningssammansättningar av inrikes och utrikes födda, samt hur tre olika geografiska indelningar av ett område påverkar utfallet av utvalda index. Uppsatsen utförs med kvantitativ metod och deduktiv slutledning. Det data som samtliga index beräknas på är syntetiskt framtagen baserad på information om hur andelarna inrikes och utrikes födda ser ut i Sveriges tre största kommuner. Mätområdet utgörs av en hypotetisk stad som delas in på tre olika sätt varpå samtliga index testas. Beräkningar och analyser görs på stickprov för respektive index och geografisk indelning. Stickproven består alla av ett hundra element och är framtagna genom ett obundet slumpmässigt urval ur en teoretisk oändlig population simulerade befolkningssammansättningar. Den geografiska effekten undersöks genom MAUPs två delproblem, Scale Effect och Zoning Effect. Utifrån studiens resultat har följande slutsatser dragits. (1) Den slumpmässiga sammansättningen av befolkningen i den hypotetiska staden påverkade generellt index väldigt lite och låg spridning av resulterade indexvärden uppmättes för många av stickproven. De undantag som påvisades var för The Entropy Index och The Dissimilarity Index. (2) Scale Effect har stor påverkan på hur samtliga index uttrycker sig samtidigt som Zoning Effect uteblir för respektive index som testas. (3) Lägre grad av segregation uppvisas då upplösningen av den geografiska informationen är lägre.
28

Membránový lis / Diaphragm Press

Krčál, Zdeněk January 2010 (has links)
The aim of this thesis is constructional concept of diaphragm press for thermoplastic forming. The press consists of two chambers. First chamber is designed for forming of semi-finished product to forming temperature and second chamber is designed for heating the semi-finished product. Theoretical part of this thesis is focused on technologies in use and shaping of plastic description. Practical part of this thesis deals with detailed description of press concept including consistence calculations and drive units calculations. The whole concept, including its individual parts, is designed using the Autodesk Inventor software. At the end of this thesis, there is the economic and safety analysis.
29

Geology of North Craters of the Moon National Monument, Idaho

Sidle, William C. 01 January 1979 (has links)
The purpose of the investigation was to map the geology of the north end of Craters of the Moon National Monument and surrounding area. A stratigraphic sequence of Late Paleozoic sedimentary and Tertiary volcanic rocks was compiles and the structures of these rocks and contact relationships with intrusions were delineated. Grade and facies of contact metamorphism were defined. The Snake River Plain basalts were also mapped. The sources of these flows were determined where possible. Preexisting structures and relationships of vents to earlier faulting were explored in ascertaining extensions of the Great Rift Zone into the Pioneer Mountains. Petrographic descriptions of the rock units were completed. Study of the economic geology was not undertaken. The interested reader is referred to Nelson (1969) for descriptions of the mineral deposits in the Lava Creek Mining District.
30

Method for Low Areal Density Material Structure Characterization: Soft X-ray Formation and Compressibility Measurement

Wang, Guizhou 21 May 2015 (has links)
No description available.

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