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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.
11

A Machine Learning-Based Statistical Analysis of Predictors for Spinal Cord Stimulation Success

Jacobson, Trolle, Segerberg, Gustav January 2019 (has links)
Spinal Cord Stimulation (SCS) is a treatment for lumbar back pain and despitethe proven effcacy of the technology, there is a lack of knowledge in how the treatment outcome varies between different patients groups. Furthermore, since the method is costly, in the sense of material, surgery and follow-up time, a more accurate patient targeting would decrease healthcare costs. Within recent years, Real World Data (RWD) has become a vital source of information to describe the effects of medical treatments. The complexity, however, calls for new, innovative methods using a larger set of useful features to explain the outcome of SCS treatments. This study has employed machine learning algorithms, e.g., Random Forest Classier (RFC) boosting algorithms to finally compare the result with the baseline; Logistic regression (LR). The results retrieved was that RFC tend to classify successful and unsuccessful patients better while logistic regression was unstable regarding unbalanced data. In order to interpret the insights of the models, we also proposed a Soft Accuracy Measurement (SAM) method to explain how RFC and LR differ. Some factors have shown to impact the success of SCS. These factors were age, income, pain experience time and educational level. Many of these variables could also be supported by earlier studies on factors of success from lumbar spine surgery.
12

Logistics and supply chain cooperative and collaborative spirit indices in South Korea

Kim, Chang Soo January 2017 (has links)
This study proposes criteria to diagnose, to analyse and to evaluate the extent of cooperation and collaboration between supply chain members within extensive inter-firm relationships in supply chains. A case study context examines cooperative and collaborative relationships between shipping companies and shippers as suppliers, manufacturers, distributers, retailers, exporters and importers. The components of cooperation and collaboration are analysed through literature reviews, interviews with industrial experts, content analysis, two-rounds of Q-sorting, and pilot testing. Cooperation is a subset of collaboration comprised of transparency, fairness, and mutuality, and cooperation and “relational strength” such as trust and sustainability constitute collaboration. A questionnaire survey generated 167 responses from shipping companies in South Korea. Exploratory factor analysis underpinned cooperative and collaborative spirit indices (CCSIs) that varied within the shipping industry, types of shipping registered, and vessel types. Confirmatory factor analysis supported good model fit, convergent and discriminant validity, and unidimensionality. A “target coefficient” identified second order factors and path analysis showed that fairness, mutuality and cooperation can foster trust, and mutual trust can cultivate sustainability although transparency does not necessarily lead to trust. CCSIs indicated modest cooperation and collaboration in the shipping industry and MANOVA revealed differences according to vessel types and contract periods. This research clarifies theories of cooperation. Enhanced CCSIs between shippers and shipping companies imply that shippers should extend two-way communication, mutuality, distributive fairness and sustainability with shipping companies. Maintaining relationships brings long run benefits. Further, shipping companies should continuously strive to gain trust from shippers and government should organise consultative groups, develop and disseminate exemplary cases and foster institutions to promote collaboration. The constructs and items deployed herein are generic, implying that the research model and CCSIs methods will be widely applicable.
13

Estimativa da recarga subterrânea em bacia hidrográfica do semiárido pernambucano a partir de técnicas de sensoriamento remoto e sistemas de informações geográficas

COELHO, Victor Hugo Rabelo 03 February 2016 (has links)
Submitted by Isaac Francisco de Souza Dias (isaac.souzadias@ufpe.br) on 2016-07-07T18:03:04Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Tese_Victor_Versão_Final.pdf: 12070696 bytes, checksum: 5580364541fc1e8bdf9f1bc84dc852fa (MD5) / Made available in DSpace on 2016-07-07T18:03:04Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Tese_Victor_Versão_Final.pdf: 12070696 bytes, checksum: 5580364541fc1e8bdf9f1bc84dc852fa (MD5) Previous issue date: 2016-02-03 / FACEPE / As limitações de dados pontuais para a estimativa da recarga subterrânea em grandes áreas ainda é um grande desafio para uma boa gestão desse recurso hídrico, principalmente em regiões semiáridas. Por causa da escassez de dados observados, a abordagem desta pesquisa estabelece uma integração entre um conjunto de variáveis do balanço hídrico, obtidas a partir de imagens de satélites, para estimar a distribuição espacial da recarga das águas subterrâneas na bacia hidrográfica do rio Ipanema (BHRI), localizada no estado de Pernambuco, Nordeste do Brasil. Os dados de sensoriamento remoto empregados incluem mapas mensais (2011-2012) de precipitação, escoamento superficial e evapotranspiração, utilizados como entradas para a aplicação do método do balanço hídrico (pixel a pixel) em um Sistema de Informação Geográfica (SIG). A precipitação utilizada foi derivada do satélite TRMM (3B43.v7) e seguiu o mesmo padrão médio mensal observado em 15 estações pluviométricas distribuídas pela área de estudo (CC = 0,93 e REQM = 17,1 mm), com estimativas médias anuais de 894,3 (2011) e 300,7 mm (2012). O escoamento superficial, adquirido pelo método SCS-CN a partir de informações dos solos da região e imagem do sensor TM, foi equivalente a 29% da precipitação registrada pelo TRMM durante os dois anos do estudo. Já a evapotranspiração real, obtida pela aplicação do SEBAL em imagens do sensor MODIS, apresentou valores médios anuais de 1.190 (2011) e 1.072 mm (2012). Os resultados do balanço hídrico mostraram que a recarga subterrânea na BHRI apresentou uma grande diferença interanual, caracterizada pelos regimes pluviométricos distintos, com médias de 28,1 (2011) e 4,9 (2012) mm ano-1. Essas recargas foram concentradas principalmente entre os meses de janeiro a julho nas regiões compostas por sedimentos aluviais e outros solos de alta permeabilidade. As aproximações da recarga subterrânea por sensoriamento remoto foram comparadas ao método WTF (Water Table Fluctuation) em uma área específica de aluvião na BHRI. As estimativas realizadas pelas duas metodologias apresentaram boa concordância anual, com valores médios de 154,6 (WTF) e 120,9 (balanço hídrico) mm em 2011, que correspondem a 14,89 e 13,12% das precipitações registradas pelo pluviômetro e pelo TRMM, respectivamente. Para o ano de 2012, apenas a metodologia WTF registrou uma recarga muito baixa de 15,9 mm. Como os estudos referentes ao tema ainda são incipientes, os valores gerados nesta tese fornecem uma boa percepção do potencial do sensoriamento remoto para avaliar as taxas desse importante componente do balanço hídrico na BHRI. / The limitations of data points to estimate the groundwater recharge over large areas are still a challenge for a good management of water resource, especially in semi-arid regions. Due to the deficiency of observed data, the approach of this research establishes an integration of hydrological cycle variables obtained from satellite images to estimate the spatial distribution of groundwater recharge in the Ipanema basin river (BHRI), located in the Pernambuco state, northeastern of Brazil. The remote sensing data used, which include monthly maps (2011-2012) of rainfall, runoff and evapotranspiration were used as input to apply the water balance method (pixel by pixel) in a Geographic Information System (GIS). The rainfall used was derived from the TRMM satellite (3B43.v7) and has the same monthly average observed temporal distribution in 15 rain gauges distributed over the study area (CC = 0.93 and RMSE = 17.1 mm), with annual average estimates of 894.3 (2011) and 300.7 mm (2012). The runoff acquired by SCS-CN method from information soil of the region and TM sensor image was equivalent to 29% of the TRMM rainfall registered during the two years of the study. The actual evapotranspiration obtained by the SEBAL application in MODIS images presented annual average of 1,190 (2011) and 1,072 (2012) mm. The results of the water balance showed a large interannual difference in the BHRI groundwater recharge, characterized by different rainfall regimes with averages of 28.1 (2011) and 4.9 (2012) mm year-1. These recharges were mainly concentrated between January to July in the regions with alluvial sediments and others high permeability soils. The groundwater recharge approach by remote sensing was compared to the WTF method (Water Table Fluctuation) in a specific area of alluvium in the BHRI. The estimates performed by the two methods showed good annual agreement, with mean values of 154.6 (WTF) and 120.9 (water balance) mm in 2011, corresponding to 14.89 and 13.12% of rainfall recorded at the rain gauge and TRMM, respectively. For the second year, just WTF method recorded a very low recharge of 15.9 mm. Studies related to the groundwater recharge involving remote sensing are incipient and the values generated in this thesis provide a good perception of the methodology to evaluate the rates of this important component of the water balance in the BHRI.
14

Assessment and Improvement of TELEMAC-2D Routines for Urban Flood Simulation

Chen, Ruijie 04 April 2022 (has links)
Pluvial flood is a natural hazard that severely threatens people’s property and safety. With the development of algorithms and computer technologies, numerical modeling has emerged as an effective tool for predicting the impacts of floods. Despite being one of the most costly types of floods in West Africa, pluvial flooding has not been studied as extensively as riverine flooding, probably because modeling runoff across urban areas remains a challenge. Recently, a module based on the SCS Curve Number Method is incorporated in the open-source software TELEAMC-2D, which provides a possibility to model the infiltration process dynamically. TELEMAC-2D is one of the first hydraulic models to consider hydrologic parameters. Although the update is expected to increase the suitability of TELAMC-2D in pluvial flood modeling, the infiltration routine has not yet been tested in a real situation in a semi-arid area. This study aims to investigate the capability of TELEMAC-2D in simulating the rainfall-runoff process during a pluvial flood event in a semi-arid urban area, Niamey city in west Africa. Due to the lack of calibration data, a hydrological model SWAT is used to evaluate the performance of TELEMAC-2D. Through the comparison between the runoffs generated by the two models, it is found that TELEMAC-2D has a similar trend with SWAT in runoff simulation. However, TELEMAC-2D significantly overestimates the runoff magnitude despite having the same SCS values as SWAT. The reason for the overestimation is TELEMAC-2D that does not properly consider evaporation. Two suggestions are made to improve pluvial floods simulations using TELEMAC-2D in semi-arid areas: 1) couple TELEMAC-2D with a hydrologic model, and use net rainfall generated by the hydrologic model as precipitation input; 2) provide functions in infiltration subroutine that calculate rainfall abstractions by other hydrologic phenomena in addition to the infiltration process.
15

Estudo sobre a sensibilidade dos parâmetros do método SCS na determinação de hidrogramas de cheia em bacias urbanas / Study on the SCS method parameter sensitivity in determination of flood hydrographs in urban basin

Paulino, Paloma Fernandes 30 September 2014 (has links)
Para simular o comportamento da bacia hidrográfica diante de eventos chuvosos e, a partir da quantificação das vazões de cheias, encontrar soluções para os problemas causados pelas enchentes, é essencial a utilização de modelos de transformação chuva-vazão. Há diferentes métodos para o cálculo do deflúvio superficial ou precipitação excedente para uma dada bacia hidrográfica. Entre estes, um dos mais utilizados pela comunidade técnica é o método desenvolvido pelo Departamento de Conservação do Solo norte-americano: SCS (Soil Conservation Service, atual National Resources Conservation Service), aplicável principalmente quando não se dispõe de séries históricas de dados hidrológicos. A utilização deste método depende da seleção do parâmetro CN (Curve Number), que por sua vez requer o conhecimento das características da bacia hidrográfica em estudo, como: tipos de solo, cobertura vegetal, uso da terra, teor de umidade do solo anterior à chuva. A partir da precipitação excedente total do evento chuvoso, para se construir um hidrograma de cheia, é necessário distribuir a chuva ao longo do tempo, ou seja, construir o hietograma da precipitação excedente. O SCS também propõe um método baseado no hidrograma unitário triangular sintético para gerar o hidrograma de cheia a partir de um certo hietograma. O parâmetro básico para se obter esse hidrograma sintético é o tempo de concentração da bacia hidrográfica (tc). Para a determinação deste parâmetro existem diversas fórmulas empíricas baseadas nas características físicas da bacia hidrográfica, uma vez que a sua determinação numa bacia sem dados hidrométricos torna-se impossível. Deste modo, para uma estimativa coerente do tc, é necessário avaliar para cada caso a ser estudado a fórmula mais adequada e os dados disponíveis. Neste sentido, o presente estudo tem como objetivo analisar a sensibilidade do método SCS em relação à classificação do uso e ocupação do solo e ao tempo de concentração, a partir de aplicação deste para a bacia do córrego do Mineirinho situada em São Carlos, SP. A análise da sensibilidade em relação ao CN foi realizada através da comparação dos resultados produzidos utilizando-se mapas de classificação dos usos do solo, produzidos a partir de imagens de satélite de alta resolução, as quais não são disponibilizadas gratuitamente, e imagens gratuitas de baixa resolução. Em relação ao tempo de concentração, foram analisadas e comparadas as diversas fórmulas disponíveis para sua determinação para uma bacia urbana. Outro aspecto estudado foi a distribuição temporal da chuva crítica. Existem diversos métodos indicados na literatura, como o dos blocos alternados, Huff e Bureau of Reclamation. Analisou-se o efeito que cada método produz nos hidrogramas de cheia resultantes. O método SCS apresenta-se bastante sensível em relação aos três parâmetros analisados. As diferenças entre os valores de CN, obtidos a partir das imagens de alta e baixa resolução, foram as que resultaram em maiores diferenças nas vazões de pico. A imagem de baixa resolução tende a subestimar as vazões de pico. Os métodos de distribuição temporal da chuva como Blocos Alternados e Huff 2°. Quartil, apesar serem métodos diferentes, produziram resultados semelhantes. / To simulate the behavior of the basin before rain events and, from the quantification of flow of floods, find solutions to the problems caused by flooding, it is essential the use of models of processing rain-flow. There are different methods for calculating the surface runoff or excess rainfall for a given basin. Among these, one of the most used by technical community is the method developed by the Department of Soil Conservation American: SCS (Soil Conservation Service, current National Resources Conservation Service), mainly applicable when there is no historical series of data hydrological. The use of this method is dependent on the selection of the parameter CN (Curve Number), which in turn requires the knowledge of the characteristics of the basin under study, such as: soil types, vegetation cover, land use, soil moisture content prior to the rain. From the total surplus precipitation of rain event, in order to build a hydrograph, it is necessary to distribute the rain over time, i.e. build the hyetogram of excess rainfall. The SCS also proposes a method based on unit hydrograph triangular synthetic. The basic parameter to obtain this synthetic hydrograph is the time of concentration of the basin (tc). For the determination of this parameter there are several empirical formulas based on the physical characteristics of the basin, since its determination in a basin without hydrometrical data becomes impossible. Thus, for a consistent estimate of tc, it is necessary to evaluate the most suitable formula and the data available for each case to be considered. In this sense, the aim of the present study is to analyze the sensitivity of the SCS method in relation to the classification of the use and occupation of the soil and the time of concentration, from application of this model to the basin of the Mineirinho located in São Carlos, SP. The sensitivity analysis in relation to the CN was performed through the comparison of the results produced using maps of classification of soil uses, produced from high-resolution satellite images, which are not made available for free, and free images of low resolution. In relation to the time of concentration, the various formulas available were analyzed and compared for its determination to an urban basin. Another aspect studied, was the temporal distribution of critical rainfall. There are several methods given in the literature, such as the Alternating Block, Huff and Bureau of Reclamation. This study aimed to analyze the effect each method produces in the resulting flood hydrographs. The SCS method is quite sensitive in relation to the three parameters analyzed. The differences between the values of CN, obtained from the images of high and low resolution, were the ones that resulted in greater differences in flow of peak. The low resolution image tends to underestimate the flow of peak. The methods of temporal distribution of rainfall as Alternating Block and Huff 2°. Quartil, despite being different methods, produced similar results.
16

Estudo sobre a sensibilidade dos parâmetros do método SCS na determinação de hidrogramas de cheia em bacias urbanas / Study on the SCS method parameter sensitivity in determination of flood hydrographs in urban basin

Paloma Fernandes Paulino 30 September 2014 (has links)
Para simular o comportamento da bacia hidrográfica diante de eventos chuvosos e, a partir da quantificação das vazões de cheias, encontrar soluções para os problemas causados pelas enchentes, é essencial a utilização de modelos de transformação chuva-vazão. Há diferentes métodos para o cálculo do deflúvio superficial ou precipitação excedente para uma dada bacia hidrográfica. Entre estes, um dos mais utilizados pela comunidade técnica é o método desenvolvido pelo Departamento de Conservação do Solo norte-americano: SCS (Soil Conservation Service, atual National Resources Conservation Service), aplicável principalmente quando não se dispõe de séries históricas de dados hidrológicos. A utilização deste método depende da seleção do parâmetro CN (Curve Number), que por sua vez requer o conhecimento das características da bacia hidrográfica em estudo, como: tipos de solo, cobertura vegetal, uso da terra, teor de umidade do solo anterior à chuva. A partir da precipitação excedente total do evento chuvoso, para se construir um hidrograma de cheia, é necessário distribuir a chuva ao longo do tempo, ou seja, construir o hietograma da precipitação excedente. O SCS também propõe um método baseado no hidrograma unitário triangular sintético para gerar o hidrograma de cheia a partir de um certo hietograma. O parâmetro básico para se obter esse hidrograma sintético é o tempo de concentração da bacia hidrográfica (tc). Para a determinação deste parâmetro existem diversas fórmulas empíricas baseadas nas características físicas da bacia hidrográfica, uma vez que a sua determinação numa bacia sem dados hidrométricos torna-se impossível. Deste modo, para uma estimativa coerente do tc, é necessário avaliar para cada caso a ser estudado a fórmula mais adequada e os dados disponíveis. Neste sentido, o presente estudo tem como objetivo analisar a sensibilidade do método SCS em relação à classificação do uso e ocupação do solo e ao tempo de concentração, a partir de aplicação deste para a bacia do córrego do Mineirinho situada em São Carlos, SP. A análise da sensibilidade em relação ao CN foi realizada através da comparação dos resultados produzidos utilizando-se mapas de classificação dos usos do solo, produzidos a partir de imagens de satélite de alta resolução, as quais não são disponibilizadas gratuitamente, e imagens gratuitas de baixa resolução. Em relação ao tempo de concentração, foram analisadas e comparadas as diversas fórmulas disponíveis para sua determinação para uma bacia urbana. Outro aspecto estudado foi a distribuição temporal da chuva crítica. Existem diversos métodos indicados na literatura, como o dos blocos alternados, Huff e Bureau of Reclamation. Analisou-se o efeito que cada método produz nos hidrogramas de cheia resultantes. O método SCS apresenta-se bastante sensível em relação aos três parâmetros analisados. As diferenças entre os valores de CN, obtidos a partir das imagens de alta e baixa resolução, foram as que resultaram em maiores diferenças nas vazões de pico. A imagem de baixa resolução tende a subestimar as vazões de pico. Os métodos de distribuição temporal da chuva como Blocos Alternados e Huff 2°. Quartil, apesar serem métodos diferentes, produziram resultados semelhantes. / To simulate the behavior of the basin before rain events and, from the quantification of flow of floods, find solutions to the problems caused by flooding, it is essential the use of models of processing rain-flow. There are different methods for calculating the surface runoff or excess rainfall for a given basin. Among these, one of the most used by technical community is the method developed by the Department of Soil Conservation American: SCS (Soil Conservation Service, current National Resources Conservation Service), mainly applicable when there is no historical series of data hydrological. The use of this method is dependent on the selection of the parameter CN (Curve Number), which in turn requires the knowledge of the characteristics of the basin under study, such as: soil types, vegetation cover, land use, soil moisture content prior to the rain. From the total surplus precipitation of rain event, in order to build a hydrograph, it is necessary to distribute the rain over time, i.e. build the hyetogram of excess rainfall. The SCS also proposes a method based on unit hydrograph triangular synthetic. The basic parameter to obtain this synthetic hydrograph is the time of concentration of the basin (tc). For the determination of this parameter there are several empirical formulas based on the physical characteristics of the basin, since its determination in a basin without hydrometrical data becomes impossible. Thus, for a consistent estimate of tc, it is necessary to evaluate the most suitable formula and the data available for each case to be considered. In this sense, the aim of the present study is to analyze the sensitivity of the SCS method in relation to the classification of the use and occupation of the soil and the time of concentration, from application of this model to the basin of the Mineirinho located in São Carlos, SP. The sensitivity analysis in relation to the CN was performed through the comparison of the results produced using maps of classification of soil uses, produced from high-resolution satellite images, which are not made available for free, and free images of low resolution. In relation to the time of concentration, the various formulas available were analyzed and compared for its determination to an urban basin. Another aspect studied, was the temporal distribution of critical rainfall. There are several methods given in the literature, such as the Alternating Block, Huff and Bureau of Reclamation. This study aimed to analyze the effect each method produces in the resulting flood hydrographs. The SCS method is quite sensitive in relation to the three parameters analyzed. The differences between the values of CN, obtained from the images of high and low resolution, were the ones that resulted in greater differences in flow of peak. The low resolution image tends to underestimate the flow of peak. The methods of temporal distribution of rainfall as Alternating Block and Huff 2°. Quartil, despite being different methods, produced similar results.
17

In vitro diferenciace testikulárních somatických buněk Xenopus tropicalis a Mus musculus. / In vitro differentiation of Xenopus tropicalis and Mus musculus testicular somatic cells.

Hlaviznová, Michaela January 2021 (has links)
Sertoli cells (SCs) are somatic cells of testicular tissue that are involved in spermatogenesis and maturation of germ cells. They are currently being extensively studied for their immunomodulatory abilities, and recent studies have shown that they share some properties with mesenchymal stromal cells (MSCs). Detailed characterization of SCs and clarification of their role in testicular tissue is crucial for potential use of SCs as a therapeutic tool in regenerative medicine. Cell culture of Xenopus tropicalis immature Sertoli cells (XtiSCs) and Mus musculus (mSCs) Sertoli cells were established in the Laboratories of Developmental Biology and Immunoregulations, Faculty of Science, Charles University. Previous research has characterized XtiSCs and demonstrated their multipotent potential by in vitro differentiation into a mesodermal line. Following this research, one of the goals of the diploma project was the induction of in vitro differentiation of XtiSC into other cell types, which would verify the differentiation potential of XtiSCs. The mSC expression profile confirmed the somatic origin of this culture as well as the transcription of Sertoli cell gene markers. Differentiation of mSCs along the mesodermal line into osteoblasts, chondrocytes and adipocytes has been successfully induced in vitro....
18

A GIS-Based Method of Deriving Spatially Distributed Unit Hydrographs / En GIS-baserad metod för att beräkna  spatialt fördelade enhetshydrografer

Lenander, Ann-Sofi January 2021 (has links)
Prior to using hydraulic and spatially distributed modelling softwares, the theory of the unit hydrograph was a commonly used tool for modelling of surface and runoff water. While distributed models often provide detailed results from extensive calculation durations, the unit hydrograph have been questioned for simplifying the physical characteristics of the watershed modelled. Typically, the unit hydrograph theory does not explicitly take the flow paths of the watershed in consideration during calculation. With the rise of geographical information systems, methods of deriving spatially distributed unit hydrographs have been developed. The aim of these have commonly been to find a spatially varied form of hydrological modelling, while still keeping the computation times low. The method is commonly built by calculating the travel time to the watershed outlet along the flow path. In this study, spatially distributed unit hydrographs are derived separately for the watershed’s pervious and impervious surfaces in a Python script using map algebra and the Esri’s Python wrapper module Arcpy. The travel times are generated from a velocity field calculated using Maidment and Olivera’s velocity equation. The velocity equation contains three unknown parameters; one for an average velocity and two calibration parameters. The excess precipitation is calculated of a 100 year return period Chicago Design Storm hyetograph using the SCS-CN method. The direct runoff hydrographs are calculated over three semi-urban watersheds in Smedby in southern Sweden, and the results are compared to MIKE 21 hydrograph data of each corresponding watershed and rain input. The result obtained showed to replicate the hydrograph response quite well, but only if the unknown parameters in the velocity equation were calibrated to match the MIKE 21 data. The unknown parameters of the velocity equations produces uncertainties of using the method without calibration data, which implies that the script is not well adapted to use for modelling predictions. It may be of interest to calculate the travel times of the locations within the watershed using a different formula. The script tool could be tested using different design storms as input, and areas of different characteristics compared to Smedby could be tested. / Innan det blev vanligt att använda hydrauliska och rumsliga modellerings- mjukvaror användes ofta teorin bakom enhetshydrografen för modellering av avrinning. Medan de rumsliga mjukvarorna ofta erbjuder detaljerade resultat till priset av långa beräkningstider, har enhetshydrografen ifrågasatts för att förenkla den fysiska karaktären av avrinningsområdet. Typiskt sett tar inte enhetshydrografen avrinningsområdets flödesvägar direkt i hänseende vid beräkning. Utveckling och ökad tillgänglighet av geografiska informations- system förenklade möjligheterna att utveckla beräkning av enhetshydrografer som tar hänsyn till avrinningsområdets karaktär, typiskt sett genom att beräkna rinntiden från varje läge i avrinningsområdet, längs rinnvägarna och till utloppet. I den här studien beräknas spatiala enhetshydrografer separat för avrinningsområdets hårdgjorda och icke hårdgjorda ytor, genom att utveckla ett Python skript med hjälp av karalgebra och Esri’s wrapper modul ArcPy. Rinntiderna från olika lägen i avrinningsområdet beräknas med Maidments och Oliveras formel för hastighet, vilken innehåller okända parametrar för en uppskattad medelhastighet samt två kalibreringsparametrar. Effektivt regn från ett Chicago Design Storm regn med en återkomsttid på 100 år beräknas med hjälp av SCS-CN metoden. Hydrograferna för direkt avrinning faltas för tre semi-urbana avrinningsområden i Smedby i södra Sverige för att sedan jämföras mot MIKE 21 genererad hydrograf data för respektive motsvarade avrinningsområde. Hydrografdata producerat av MIKE 21 har tagits fram med lika CDS-regn data som input. Resultatet visar att hydrografer snarlika MIKE 21 hydrograferna kan tas fram med Maidments spatialt fördelade enhetshydrograf, om de okända parametrarna i Maidments formel kalibrerades mot MIKE 21 data. Utan kalibreringsdata för att bestämma de okända parametrarna kan resultatet anses vara mycket osäkert, vilket antyder att Python skriptet ej bör användas för använda metoden för att förutspå responser av regnevent. Andra beräkningar än Maidments ekvation kan vara av intresse att implementera. Olika typer av regninput samt spatial data över andra platser än Smedby kan vara av intresse att testa Python skriptet för.
19

Relationen mellan mindfulness, självmedkänsla och upplevd stress bland universitetsstudenter

Sandberg, Vilmer, Modig, Simon January 2016 (has links)
Stress är ett växande samhällsproblem och står för en tredjedel av alla sjukskrivningar i Sverige. Många företag uppger att de inte har metoder för att hantera stress. Därmed finns ett stort behov av effektiva metoder för detta. Mindfulness based stress reduction (MBSR) verkar vara en effektiv metod för att minska stress, men verkningsmekanismerna är ej helt fastställda. Både mindfulness och självmedkänsla förefaller kunna ha inverkan på stress. Syftet med denna studie är att undersöka vilken relation mindfulness och självmedkänsla har till upplevd stress bland universitetsstudenter samt om något av begreppen har en starkare relation till upplevd stress än det andra. Tre validerade självskattningsinstrument, Self-Compassion Scale (SCS), Five Facet Mindfulness Questionaire (FFMQ-S) och Perceived Stress Scale-14 (PSS-14), administrerades till 203 universitetsstudenter. I enlighet med förväntningarna fanns det ett statistiskt signifikant samband mellan FFMQ och SCS. Regressionsanalyser visade att både FFMQ och SCS predicerade poäng på PSS-14 och att SCS kunde predicera poäng på  PSS-14 i högre grad än FFMQ. Kön var också en signifikant prediktor av poäng på PSS-14, men dess prediktiva värde var ej signifikant när FFMQ och SCS inkluderades i regressionsmodellen. Fyndet tyder på att självmedkänsla är en viktig del i hanteringen av stress och bidrar med en ledtråd i verkningsmekanismerna i MBSR och andra copingstrategier. Mer forskning behövs för att vidare utreda kausalitet och hur de olika komponenterna i självmedkänsla verkar på upplevd stress. / Stress is a growing social problem which accounts for a third of all sick leave in Sweden. Many companies say they do not have methods to manage stress. Thus there is a great need for effective methods to manage stress with. Mindfulness Based Stress Reduction (MBSR) is an effective method to reduce stress, however the mechanisms are not completely understood. Research indicates that Self-compassion seems to have a significant role. Both mindfulness and self-compassion hence seems to be able to have an impact on stress. The purpose of this study is to examine what relationship mindfulness and self-compassion has with perceived stress, and if any of the concepts has a stronger relationship to perceived stress than the other. Three validated self-report instruments, Self-Compassion Scale (SCS), Five Facet Mindfulness Questionnaire (FFMQ) and Perceived Stress Scale-14 (PSS14), were administered to 203 university students. The collected data was analyzed with regression analysis. In line with expectations, mindfulness and self-compassion correlated. The results also indicated that both FFMQ and SCS can predict PSS-14 scores, and that scores on SCS could predict scores on PSS-14 to a greater extent than FFMQ could. Gender did also significantly predict scores on PSS-14, but it did not have any significant predictive value when SCS and FFMQ was included in the regression analysis. These findings suggests that self-compassion is an important part of managing stress and therefore might be a significant mechanism of action of MBSR and other coping strategies. More research is needed to further investigate causality, and the function of the various components of self-compassion on perceived stress.
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Hur perfekt får en vara? : Prediktorer för förändring vid internetbaserad kognitiv beteendeterapi för perfektionism / How perfect can you be? : Predictors of change in Internet-based cognitive behaviour therapy for perfectionism

Skoglund, Malin, Trosell, Linnéa January 2016 (has links)
Perfectionism has been seen to predict treatment outcome and symptom severity in clinically relevant diagnoses such as depression and anxiety disorders. It has also been suggested to be a transdiagnostic phenomenon. The aim of this study was to investigate, for the first time, predictors of change in Internet-based cognitive behaviour therapy for perfectionism. The chosen predictors were perfectionism severity, comorbid diagnosis and degree of self-compassion. The study was a part of the Devin-project; a randomized controlled trial with 150 participants that were allocated to active treatment (N=73) or a waitlist condition (N=77). Multiple linear regression analysis was used for the analyses. Variables chosen a priori did not significantly predict the treatment outcome (R2=.10, p = .099). A post hoc-analysis showed that perfectionism severity, as measured with CPQ, predicted symptom change after treatment (B = .783, β = .56 p < .001). The results indicate that perfectionism severity doesn’t impair the treatment effects and that the treatment is effective, independent of comorbid diagnoses. Self-compassion was investigated on an explorative basis but the results can indicate that the variable is not a risk factor nor a protective factor for perfectionism. As Devin is the largest randomized controlled study of internet-based cognitive behaviour therapy for perfectionism to date, this study generates important implications and suggestions for future research. / Devin

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