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Seismic Response of Structures on Shallow Foundations over Soft Clay Reinforced by Soil-Cement GridsKhosravi, Mohammad 21 September 2016 (has links)
This study uses dynamic centrifuge tests and three-dimensional (3D), nonlinear finite-difference analyses to: (1) evaluate the effect of soil-cement grid reinforcement on the seismic response of a deep soft soil profile, and (2) to examine the dynamic response of structures supported by shallow foundations on soft clay reinforced by soil-cement grids. The soil profile consisted of a 23-m-thick layer of lightly over-consolidated clay, underlain and overlain by thin layers of dense sand. Centrifuge models had two separate zones for a total of four different configurations: a zone without reinforcement, a zone with a "embedded" soil-cement grid which penetrated the lower dense sand layer and had a unit cell area replacement ratio Ar = 24%, a zone with an embedded grid with Ar = 33%, and a zone with a "floating" grid in the upper half of the clay layer with Ar = 33%. Models were subjected to a series of shaking events with peak base accelerations ranging from 0.005 to 0.54g. The results of centrifuge tests indicated that the soil-cement grid significantly stiffened the site compared to the site with no reinforcement, resulting in stronger accelerations at the ground surface for the input motions used in this study. The response of soil-cement grid reinforced soft soil depends on the area replacement ratio, depth of improvement and ground motion characteristics. The recorded responses of the structures and reinforced soil profiles were used to define the dynamic moment-rotation-settlement responses of the shallow foundations across the range of imposed shaking intensities. The results from centrifuge tests indicated that the soil-cement grids were effective at controlling foundation settlements for most cases; onset of more significant foundation settlements did develop for the weakest soil-cement grid configuration under the stronger shaking intensities which produced a rocking response of the structure and caused extensive crushing of the soil-cement near the edges of the shallow foundations. Results from dynamic centrifuge tests and numerical simulations were used to develop alternative analysis methods for predicting the demands imposed on the soil-cement grids by the inertial loads from the overlying structures and the kinematic loading from the soil profile's dynamic response. / Ph. D.
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Rocking shear wall foundations in regions of moderate seismicityVan der Merwe, Johann Eduard 12 1900 (has links)
Thesis (MScEng (Civil Engineering))--University of Stellenbosch, 2009. / ENGLISH ABSTRACT: In regions of moderate seismicity it has been shown that a suitable structural system is
created when designing the shear wall with a plastic hinge zone at the lower part of the
wall, with the shear walls resisting lateral loads and all other structural elements
designed to resist gravity loads. A suitably stiff foundation is required for the
assumption of plastic hinge zones to hold true. This foundation should have limited
rotation and should remain elastic when lateral loads are applied to the structure.
Ensuring a foundation with a greater capacity than the shear wall results in excessively
large shear wall foundations being required in areas of moderate seismicity for
buildings with no basement level.
This study aims to investigate the feasibility of reducing the size of shear wall
foundations in areas of moderate seismicity for buildings with no basement level. The
investigation is aimed at allowing shear wall foundation rocking and taking into account
the contribution of structural frames to the lateral stiffness of the structure. An example
building was chosen to investigate this possibility.
Firstly, lateral force-displacement capacities were determined for a shear wall and an
internal reinforced concrete frame of this investigated building. Nonlinear momentrotation
behaviour was determined for the wall foundation size that would traditionally
be required as well as for six other smaller foundations.
The above capacity curves against lateral loads were then used to compile a simplified
model of the structural systems assumed to contribute to the lateral stiffness of the
building. This simplified model therefore combined the effect of the shear wall, internal
frame and wall foundation.
Nonlinear time-history analyses were performed on this simplified model to investigate
the dynamic response of the structure with different wall foundation sizes. By assessing
response results on a global and local scale, it was observed that significantly smaller
shear wall foundations are possible when allowing foundation rocking and taking into
account the contribution of other structural elements to the lateral stiffness of the
building. / AFRIKAANSE OPSOMMING: Daar is reeds getoon dat ʼn voldoende strukturele sisteem verkry word in gebiede van
gematigde seismiese risiko indien ʼn skuifmuur ontwerp word met ʼn plastiese skarnier
sone naby die ondersteuning van die muur. Skuifmure word dan ontwerp om weerstand
te bied teen laterale kragte met alle ander strukturele elemente ontwerp om gravitasie
kragte te weerstaan. Vir die aanname van plastiese skarnier sones om geldig te wees
word ʼn fondasie met voldoende styfheid benodig. Só ʼn fondasie moet beperkte rotasie
toelaat en moet elasties bly wanneer laterale kragte aan die struktuur aangewend word.
ʼn Fondasie met ʼn groter kapasiteit as dié van die skuifmuur lei daartoe dat uitermate
groot fondasies benodig word in gebiede van gematigde seismiese risiko vir geboue met
geen kelder vlak.
Hierdie studie is daarop gemik om die moontlikheid van kleiner skuifmuur fondasies te
ondersoek vir geboue met geen kelder vlak in gebiede van gematigde seismiese risiko.
Die ondersoek het ten doel om skuifmuur fondasie wieg aksie toe te laat en die bydrae
van strukturele rame tot die laterale styfheid van die struktuur in ag te neem.
Eerstens is die laterale krag-verplasing kapasiteit van ʼn skuifmuur en ʼn interne
gewapende beton raam van die gekose gebou bepaal. Nie-lineêre moment-rotasie
gedrag is bepaal vir die skuifmuur fondasie grootte wat tradisioneel benodig sou word
asook vir ses ander kleiner fondasie grotes.
Die bogenoemde kapasiteit kurwes is gebruik om ʼn vereenvoudigde model van die
strukturele sisteme wat aanvaar word om laterale styfheid tot die gebou te verleen, op te
stel. Hierdie vereenvoudigde model kombineer gevolglik die effek van die skuifmuur,
interne raam en skuifmuur fondasie.
Nie-lineêre tydgeskiedenis analises is uitgevoer op die vereenvoudigde model ten einde
die dinamiese reaksie van die struktuur te ondersoek vir verskillende fondasie grotes.
Resultate is beoordeel op ʼn globale en lokale vlak. Daar is waargeneem dat aansienlik
kleiner skuifmuur fondasies moontlik is deur wieg aksie van die fondasie toe te laat en
die bydrae van ander strukturele elemente tot die laterale styfheid van die gebou in ag te
neem.
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Consumo de água da cultura da estévia (Stevia rebaudiana (Bert.) Bertoni) estimado por microlisímetro automático. / Water consumption of estevia (stevia rebaudian a (Bert.) Bertoni) estimate by automatic microlysimeter.Fronza, Diniz 03 May 2002 (has links)
Este trabalho teve como objetivos estimar o consumo hídrico da cultura da estévia utilizando dois microlisímetros de lençol freático de nível constante, bem como determinar as funções de resposta de lâminas de irrigação no rendimento de folhas da cultura. A pesquisa foi realizada na área experimental do Departamento de Agronomia e Gestão do Agroecossistema da Universidade de Pisa, em San Piero a Grado Pisa/Itália. A evapotranspiração de referência foi determinada pelo método Penman-Monteith-FAO. Os dados de evapotranpiração foram coletados diariamente durante o período de junho a outubro de 2000. O lençol freático dos dois microlisímetros foi mantido a 35 cm da superfície do solo. As lâminas de irrigação aplicadas foram 64%, 80%, 100%, 117% da evapotranspiração medida pelos microlisímetros e um tratamento testemunha sem irrigação, sendo 4 repetições em cada tratamento. O potencial de água no solo nos tratamentos foi monitorado com tensiômetros istalados nas profundidades de 10 cm, 20 cm, 30 cm e 40 cm de profundidade. A evapotranspiração da cultura durante todo ciclo (80dias) foi de 464 mm. Os valores médios de evapotranspiração para a fase de maoir consumo, ou seja, fase final, foram de 5,44 mm.dia-1. Os valores de coeficientes de cultura foram de 1,45 para a fase inicial, 1,14 para a intermediária e 1,16 para a fase final do desenvolvimento da cultura. O uso das maiores lâminas de irrigação, 117% ETE (538 mm ) e 100% ETE (464 mm) promoveram o maior rendimento de folhas, com 5130 Kg.ha-1 e 4931 Kg.ha-1, respectivamente. Esses valores foram 113% e 105% superiores ao tratamento sem irrigação. O rendimento da cultura decresceu conforme aumentou a tensão de água no solo. O uso das diferentes lâminas de irrigação não afetou o teor de esteviosídeo nas folhas, com um valor mádio de 6,49%. O intervalo de irrigação de 3 dias não afetou o rendimento quando foi aplicado a maior lâmina de irrigação (117%). / The aim of this work was to estimate the water consumption of stevia using two constant watertable microlysimeters and determine the irrigation levels response in the yield. The research was conducted at the Department of Agronomy and Agroecosystem Gestion experimental area of the Pisa University, in San Piero a Grado-Pisa/Itália. The reference evapotranspiration e was determined by the Penman-Monteith-FAO method. The data was daily coleected from June to October 2000. The two microlysimeters watertable had been maintained at 35 cm depth. The irrigation levls were 15%, 64%, 80%, 100% and 117% of evapotranspiration (ETP), measured by capillary ascension microlisymeter. The experimental design was entirely randomize with 4 repetitions and 20 plots. The soil water potential was measured by tensiometers installed at 10 cm, 20 cm, 30 cm and 40 cm. The crop evapotranspiration in the total cicle (80 days) was 464 mm. For the most water consumption phase, the crop evapotranspiration average was 5,44 mm.day-1. The crop coefficient values were 1,14 for the next period (from 26 to 50 days), and 1,16 for the latest one (from 51 to 80 days). The greatest yield was obtained by 117% ETE (538 mm) and 100% ETE (464 mm) irrigation levels, with 5130 Kg.ha-1 and 4931 Kg.ha-1, respectively. These values were 113% and 105% higher than the treatment without irrigation. The yield decreased according to increased the soil water tension. The different irrigation levels did not affect the esteviodeo content, with an average of 6,49%. Until 3 days between irrigation under the 117% ETE, the crops yield was not affected significatevily.
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Efeito do manejo da palha da cana-de-açúcar nas propriedades físico-hídricas de um solo. / Effect of sugarcane trash management on physical and hydrological soil properties.Timm, Luís Carlos 19 April 2002 (has links)
Diferentes práticas de manejo da cultura de cana-de-açúcar foram estudadas por meio da avaliação de propriedades físico-hídricas do solo. Os principais aspectos avaliados foram as variações da umidade do solo, temperatura do solo, fluxo de água no solo, armazenamento da água no solo e escoamento de superficial durante um período de dois anos, um de cana-planta e um de soqueira. As diferentes práticas de manejo foram: i. entrelinha com solo nu; ii. presença de cobertura vegetal na superfície do solo (palhas + ponteiros) após a colheita; e iii. presença de resíduos na superfície do solo provenientes da queima da cana antes da colheita. Algumas variáveis foram amostradas ao longo de uma transeção de 84 pontos, com o objetivo de aplicar técnicas geoestatísticas e a abordagem de espaço de estados. O efeito da cobertura vegetal na superfície do solo, como uma conseqüência da adoção da nova prática de colheita sem queima prévia da cana, reduziu as temperaturas médias na camada superficial do solo na ordem de 7 o C, evitando picos de temperatura na superfície durante o período inicial de estabelecimento da cana soca. A cobertura vegetal, contudo, afetou negativamente o desenvolvimento da cultura reduzindo o número de colmos e seu peso úmido, no presente estudo em torno de 13 %. Por outro lado, a presença da cobertura vegetal não afetou nenhum dos seguintes componentes do balanço hídrico: escoamento superficial, fluxo de água no solo no limite inferior do volume de solo em estudo e o armazenamento de água no solo, sendo o estabelecimento do balanço hídrico da cultura de cana-de-açúcar, prevalecendo estas condições, problemático principalmente devido ao fato de que o escoamento superficial e os fluxos de água no limite inferior do volume de solo considerado foram fortemente afetados pela variabilidade espacial do solo. A análise de espaço de estados aplicada à dados de umidade e temperatura do solo coletados ao longo da transeção espacial de 84 pontos, sugeriu que, em muitas situações, devido ao fato de que os dados de temperatura do solo são mais fáceis e mais rápidos de serem obtidos no campo de que os de umidade, uma medida poderia substituir a outra. Quando esta análise foi aplicada à dados de umidade do solo, matéria orgânica do solo, conteúdo de argila e estabilidade de agregados coletados ao longo da mesma transeção, foi possível identificar como uma variável se relaciona ao comportamento local de outras variáveis e estocasticamente quantificar este relacionamento, levando em consideração os erros associados às observações e ao modelo. Devido a isto, a análise de espaço de estados é uma ferramenta analítica aplicável sob condições locais no campo, podendo, potencialmente, ajudar os agricultores no manejo adequado do solo e dos recursos naturais para o aumento da produção e, simultaneamente, a qualidade do meio ambiente. / Different practices of sugarcane trash management were studied by the evaluation of soil physical and hydrological properties. The main aspects evaluated were changes in soil water content, soil temperature, soil water fluxes, soil water storage and run-off during a period of two years, corresponding to the planted sugarcane crop and the first ratoon crop. The different management practices were: i. interrow with bare soil; ii. trash mulching, maintaining harvest residues (straw + tips) on soil surface; iii. soil with residues of trash burning prior harvest. Some variables were also collected along a 84 point transect aiming to apply geostatistical techniques and state-space approach. The effect of soil surface mulching in sugarcane ratoon crops, as a consequence of the adoption of new harvest practices with no straw burning, can reduce average soil surface layer temperatures by about 7 o C, avoiding peak surface temperatures during the initial period of the ratoon crop establishment. The mulch can, however, affect negatively the crop development reducing the number of stalks and their weight, in the present case by about 13%. On the other hand, mulching did not affect any of the following water balance components: run-off, soil water fluxes at the lower soil volume limit, and soil water storage. The establishment of the water balance of the sugarcane crop, under these prevailing conditions, was problematic mainly due to the run-off and soil water flux components which were strongly affected by soil spatial variability. The state-space approach applied to soil water content and soil temperature data along the 84 point transect suggested that, in many situations, since temperature measurements are easier and quicker to be measured than those of soil water content, one measurement could replace the other. On the other hand, when the state-space analysis was applied to soil water content, soil organic matter, clay content and aggregate stability data set along the same transect, it was possible to identify a variable that relates to the local behavior of several variables and stochastically quantify that relationship accounting for both, measurement and model errors. Due to the fact that the state-space approach is an analytical tool applicable to local field conditions, it potentially helps farmers to manage soil and soil resources adequately to maximize crop production and to simultaneously improve the quality of the local environment.
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Seismic response analysis of linear and nonlinear secondary structuresKasinos, Stavros January 2018 (has links)
Understanding the complex dynamics that underpin the response of structures in the occurrence of earthquakes is of paramount importance in ensuring community resilience. The operational continuity of structures is influenced by the performance of nonstructural components, also known as secondary structures. Inherent vulnerability characteristics, nonlinearities and uncertainties in their properties or in the excitation pose challenges that render their response determination as a non-straightforward task. This dissertation settles in the context of mathematical modelling and response quantification of seismically driven secondary systems. The case of bilinear hysteretic, rigid-plastic and free-standing rocking oscillators is first considered, as a representative class of secondary systems of distinct behaviour excited at a single point in the primary structure. The equations governing their full dynamic interaction with linear primary oscillators are derived with the purpose of assessing the appropriateness of simplified analysis methods where the secondary-primary feedback action is not accounted for. Analyses carried out in presence of pulse-type excitation have shown that the cascade approximation can be considered satisfactory for bilinear systems provided the secondary-primary mass ratio is adequately low and the system does not approach resonance. For the case of sliding and rocking systems, much lighter secondary systems need to be considered if the cascade analysis is to be adopted, with the validity of the approximation dictated by the selection of the input parameters. Based on the premise that decoupling is permitted, new analytical solutions are derived for the pulse driven nonlinear oscillators considered, conveniently expressing the seismic response as a function of the input parameters and the relative effects are quantified. An efficient numerical scheme for a general-type of excitation is also presented and is used in conjunction with an existing nonstationary stochastic far-field ground motion model to determine the seismic response spectra for the secondary oscillators at given site and earthquake characteristics. Prompted by the presence of uncertainty in the primary structure, and in line with the classical modal analysis, a novel approach for directly characterising uncertainty in the modal shapes, frequencies and damping ratios of the primary structure is proposed. A procedure is then presented for the identification of the model parameters and demonstrated with an application to linear steel frames with uncertain semi-rigid connections. It is shown that the proposed approach reduces the number of the uncertain input parameters and the size of the dynamic problem, and is thus particularly appealing for the stochastic assessment of existing structural systems, where partial modal information is available e.g. through operational modal analysis testing. Through a numerical example, the relative effect of stochasticity in a bi-directional seismic input is found to have a more prominent role on the nonlinear response of secondary oscillators when compared to the uncertainty in the primary structure. Further extending the analyses to the case of multi-attached linear secondary systems driven by deterministic seismic excitation, a convenient variant of the component-mode synthesis method is presented, whereby the primary-secondary dynamic interaction is accounted for through the modes of vibration of the two components. The problem of selecting the vibrational modes to be retained in analysis is then addressed for the case of secondary structures, which may possess numerous low frequency modes with negligible mass, and a modal correction method is adopted in view of the application for seismic analysis. The influence of various approaches to build the viscous damping matrix of the primary-secondary assembly is also investigated, and a novel technique based on modal damping superposition is proposed. Numerical applications are demonstrated through a piping secondary system multi-connected on a primary frame exhibiting various irregularities in plan and elevation, as well as a multi-connected flexible secondary system. Overall, this PhD thesis delivers new insights into the determination and understanding of the response of seismically driven secondary structures. The research is deemed to be of academic and professional engineering interest spanning several areas including seismic engineering, extreme events, structural health monitoring, risk mitigation and reliability analysis.
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Informovanost rodičů a dětských sester o kojeneckém spánku / Parents and Peadiatric Nurses Awareness of Infant SleepŠIPANOVÁ, Renáta January 2014 (has links)
One of the most common complaints of mothers at the paediatrician's is complaint about the night sleep disorder, especially in older infants and toddlers. Long-term insomnia of a child negatively affects well-being of parents and disrupts peaceful atmosphere of home. We often encounter sleep disorders in babies; mostly they are frequent nocturnal awakenings and difficulty falling asleep. Parents should be therefore informed about sleep issues already at neonatal units, as they are informed about breastfeeding. The target group of this research was mothers of infants and nurses working at neonatal units and in primary paediatric care. The aim of the study was to determine the level of awareness of paediatric nurses and parents about infant sleep and create educational material for nurses. The survey was carried out using a snow ball technique, in-depth interviews with mothers and a questionnaire with open questions for nurses. Collected data were then transcribed, coded, and processed using frame analysis by. Then, using the snow ball method, we gradually extended the sample to 7 mothers of unsleepy infants and 7 mothers of sleepy infants, i.e. to cases that were supposed to strongly manifest the problem. Also, paediatric nurses were selected intentionally according to their place of work at neonatal departments and in primary paediatric care. Parents receive information about infant sleep most often on the Internet, from specialized books and from their own mothers and friends; and they usually do not ask nurses for information on infant sleep. Parent only find out at home that there is a problem with their child's sleep. They tend to try various interventions to lull their baby to sleep. Research has shown that the most common source of knowledge for nurses is their personal experience with their own children. Nurses also use their rich experience gained during long years of practice. Furthermore, they educate themselves in this issue using specialized books, visiting seminars, and they also use the internet. Nurses' advice to mothers regarding infant insomnia is shown in two perspectives in our research. The first is the perspective of mothers and the second one is the perspective of nurses. Surprisingly, there are discrepancies, especially regarding the nurses in primary care. Interventions that were reported by nurses coincide with working techniques of lulling a baby to sleep. In contrast, some interventions which were described by mothers as advice from a nurse rather indicate ignorance or indifference of some nurses. The research showed that the quality of infant sleep may be to some extent influenced by the information given to parents already at neonatal unit by medical staff, because they are in the best position to provide such information. However, mothers often choose different sources. The research has shown that mothers usually instinctively select proper techniques to lull restless infants to sleep without consulting a paediatric nurse. These results have prompted the development of an educational leaflet for nurses which informs about proper practices and appropriate techniques to lull restless unsleepy infants to sleep.
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Efeito do manejo da palha da cana-de-açúcar nas propriedades físico-hídricas de um solo. / Effect of sugarcane trash management on physical and hydrological soil properties.Luís Carlos Timm 19 April 2002 (has links)
Diferentes práticas de manejo da cultura de cana-de-açúcar foram estudadas por meio da avaliação de propriedades físico-hídricas do solo. Os principais aspectos avaliados foram as variações da umidade do solo, temperatura do solo, fluxo de água no solo, armazenamento da água no solo e escoamento de superficial durante um período de dois anos, um de cana-planta e um de soqueira. As diferentes práticas de manejo foram: i. entrelinha com solo nu; ii. presença de cobertura vegetal na superfície do solo (palhas + ponteiros) após a colheita; e iii. presença de resíduos na superfície do solo provenientes da queima da cana antes da colheita. Algumas variáveis foram amostradas ao longo de uma transeção de 84 pontos, com o objetivo de aplicar técnicas geoestatísticas e a abordagem de espaço de estados. O efeito da cobertura vegetal na superfície do solo, como uma conseqüência da adoção da nova prática de colheita sem queima prévia da cana, reduziu as temperaturas médias na camada superficial do solo na ordem de 7 o C, evitando picos de temperatura na superfície durante o período inicial de estabelecimento da cana soca. A cobertura vegetal, contudo, afetou negativamente o desenvolvimento da cultura reduzindo o número de colmos e seu peso úmido, no presente estudo em torno de 13 %. Por outro lado, a presença da cobertura vegetal não afetou nenhum dos seguintes componentes do balanço hídrico: escoamento superficial, fluxo de água no solo no limite inferior do volume de solo em estudo e o armazenamento de água no solo, sendo o estabelecimento do balanço hídrico da cultura de cana-de-açúcar, prevalecendo estas condições, problemático principalmente devido ao fato de que o escoamento superficial e os fluxos de água no limite inferior do volume de solo considerado foram fortemente afetados pela variabilidade espacial do solo. A análise de espaço de estados aplicada à dados de umidade e temperatura do solo coletados ao longo da transeção espacial de 84 pontos, sugeriu que, em muitas situações, devido ao fato de que os dados de temperatura do solo são mais fáceis e mais rápidos de serem obtidos no campo de que os de umidade, uma medida poderia substituir a outra. Quando esta análise foi aplicada à dados de umidade do solo, matéria orgânica do solo, conteúdo de argila e estabilidade de agregados coletados ao longo da mesma transeção, foi possível identificar como uma variável se relaciona ao comportamento local de outras variáveis e estocasticamente quantificar este relacionamento, levando em consideração os erros associados às observações e ao modelo. Devido a isto, a análise de espaço de estados é uma ferramenta analítica aplicável sob condições locais no campo, podendo, potencialmente, ajudar os agricultores no manejo adequado do solo e dos recursos naturais para o aumento da produção e, simultaneamente, a qualidade do meio ambiente. / Different practices of sugarcane trash management were studied by the evaluation of soil physical and hydrological properties. The main aspects evaluated were changes in soil water content, soil temperature, soil water fluxes, soil water storage and run-off during a period of two years, corresponding to the planted sugarcane crop and the first ratoon crop. The different management practices were: i. interrow with bare soil; ii. trash mulching, maintaining harvest residues (straw + tips) on soil surface; iii. soil with residues of trash burning prior harvest. Some variables were also collected along a 84 point transect aiming to apply geostatistical techniques and state-space approach. The effect of soil surface mulching in sugarcane ratoon crops, as a consequence of the adoption of new harvest practices with no straw burning, can reduce average soil surface layer temperatures by about 7 o C, avoiding peak surface temperatures during the initial period of the ratoon crop establishment. The mulch can, however, affect negatively the crop development reducing the number of stalks and their weight, in the present case by about 13%. On the other hand, mulching did not affect any of the following water balance components: run-off, soil water fluxes at the lower soil volume limit, and soil water storage. The establishment of the water balance of the sugarcane crop, under these prevailing conditions, was problematic mainly due to the run-off and soil water flux components which were strongly affected by soil spatial variability. The state-space approach applied to soil water content and soil temperature data along the 84 point transect suggested that, in many situations, since temperature measurements are easier and quicker to be measured than those of soil water content, one measurement could replace the other. On the other hand, when the state-space analysis was applied to soil water content, soil organic matter, clay content and aggregate stability data set along the same transect, it was possible to identify a variable that relates to the local behavior of several variables and stochastically quantify that relationship accounting for both, measurement and model errors. Due to the fact that the state-space approach is an analytical tool applicable to local field conditions, it potentially helps farmers to manage soil and soil resources adequately to maximize crop production and to simultaneously improve the quality of the local environment.
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Consumo de água da cultura da estévia (Stevia rebaudiana (Bert.) Bertoni) estimado por microlisímetro automático. / Water consumption of estevia (stevia rebaudian a (Bert.) Bertoni) estimate by automatic microlysimeter.Diniz Fronza 03 May 2002 (has links)
Este trabalho teve como objetivos estimar o consumo hídrico da cultura da estévia utilizando dois microlisímetros de lençol freático de nível constante, bem como determinar as funções de resposta de lâminas de irrigação no rendimento de folhas da cultura. A pesquisa foi realizada na área experimental do Departamento de Agronomia e Gestão do Agroecossistema da Universidade de Pisa, em San Piero a Grado Pisa/Itália. A evapotranspiração de referência foi determinada pelo método Penman-Monteith-FAO. Os dados de evapotranpiração foram coletados diariamente durante o período de junho a outubro de 2000. O lençol freático dos dois microlisímetros foi mantido a 35 cm da superfície do solo. As lâminas de irrigação aplicadas foram 64%, 80%, 100%, 117% da evapotranspiração medida pelos microlisímetros e um tratamento testemunha sem irrigação, sendo 4 repetições em cada tratamento. O potencial de água no solo nos tratamentos foi monitorado com tensiômetros istalados nas profundidades de 10 cm, 20 cm, 30 cm e 40 cm de profundidade. A evapotranspiração da cultura durante todo ciclo (80dias) foi de 464 mm. Os valores médios de evapotranspiração para a fase de maoir consumo, ou seja, fase final, foram de 5,44 mm.dia-1. Os valores de coeficientes de cultura foram de 1,45 para a fase inicial, 1,14 para a intermediária e 1,16 para a fase final do desenvolvimento da cultura. O uso das maiores lâminas de irrigação, 117% ETE (538 mm ) e 100% ETE (464 mm) promoveram o maior rendimento de folhas, com 5130 Kg.ha-1 e 4931 Kg.ha-1, respectivamente. Esses valores foram 113% e 105% superiores ao tratamento sem irrigação. O rendimento da cultura decresceu conforme aumentou a tensão de água no solo. O uso das diferentes lâminas de irrigação não afetou o teor de esteviosídeo nas folhas, com um valor mádio de 6,49%. O intervalo de irrigação de 3 dias não afetou o rendimento quando foi aplicado a maior lâmina de irrigação (117%). / The aim of this work was to estimate the water consumption of stevia using two constant watertable microlysimeters and determine the irrigation levels response in the yield. The research was conducted at the Department of Agronomy and Agroecosystem Gestion experimental area of the Pisa University, in San Piero a Grado-Pisa/Itália. The reference evapotranspiration e was determined by the Penman-Monteith-FAO method. The data was daily coleected from June to October 2000. The two microlysimeters watertable had been maintained at 35 cm depth. The irrigation levls were 15%, 64%, 80%, 100% and 117% of evapotranspiration (ETP), measured by capillary ascension microlisymeter. The experimental design was entirely randomize with 4 repetitions and 20 plots. The soil water potential was measured by tensiometers installed at 10 cm, 20 cm, 30 cm and 40 cm. The crop evapotranspiration in the total cicle (80 days) was 464 mm. For the most water consumption phase, the crop evapotranspiration average was 5,44 mm.day-1. The crop coefficient values were 1,14 for the next period (from 26 to 50 days), and 1,16 for the latest one (from 51 to 80 days). The greatest yield was obtained by 117% ETE (538 mm) and 100% ETE (464 mm) irrigation levels, with 5130 Kg.ha-1 and 4931 Kg.ha-1, respectively. These values were 113% and 105% higher than the treatment without irrigation. The yield decreased according to increased the soil water tension. The different irrigation levels did not affect the esteviodeo content, with an average of 6,49%. Until 3 days between irrigation under the 117% ETE, the crops yield was not affected significatevily.
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Gungstolsterapi – en omvårdnadsåtgärd i psykiatrisk heldygnsvård : En stol som berör / Rocking chair therapy – a nursing intervention in mental health care : Moving emotionsPalm, Bonita January 2017 (has links)
Bakgrund: Gungstolsterapi som omvårdnadsåtgärd är outforskat inom den psykiatriska heldygnsvården. Vetenskapliga studier av den typ av gungstol som här studerats har inte gått att hitta. Syfte: Syftet med studien var att utvärdera gungstolsterapi som omvårdnadsåtgärd vid en psykiatrisk heldygnsvårdsavdelning. Metod: En naturalistisk studie med både kvantitativa och kvalitativa inslag genomfördes. Under studieperioden fick patienter som vårdades på en psykiatrisk heldygnsvårdsavdelning lämna självskattningar på en VAS-skala avseende sitt mående före och efter genomförd gungstolsterapi. Patienterna kunde också lämna en skriftlig kommentar om gungningen. Resultat: Resultatet visar att deltagarna skattat en genomsnittlig förbättring motsvarande 16%-enheter i sitt generella mående efter genomförd gungning. Genomsnittliga gungtid var 33 min/gungtillfälle. Majoriteten av patienterna som deltog i studien har bipolär sjukdom. Många deltagare föredrog att gunga en viss del av dygnet. Innehållsanalysen av kommentarerna ledde till att fem kategorier bildades som sammanfattades i temat "En stol som berör". Den genomförda studien visar att patienterna generellt sett upplevde ett ökat välbefinnande efter gungstolsterapin. Studien visar också att inga allvarliga händelser inträffat vid användningen av gungstolen. Resultatet i de båda delarna av studien harmonierar väl med varandra. Slutsats: Studien ger underlag att rekommendera patienter gungstolsterapi för att förbättra sitt mående eller i symtomlindrande syfte. Genomgången visar att många patienter har individuella preferenser för sitt gungande. Gungstolsterapi bör ses som en hälsofrämjande egenvårdsåtgärd som patienten kan utföra dygnet runt och som kan läggas in i patientens vårdplan. / Background: Rocking chair therapy has been poorly researched. There are no scientific research studies where the current rocking chair was evaluated. Aim: The aim of the study was to evaluate rocking chair therapy as a nursing intervention in an inpatient psychiatric setting. Method: A mixed method design, combining quantitative and qualitative approaches, was used. The participants were asked to rate their well-being in a form by using a Visual Analogue Scale (VAS) before and after rocking chair therapy. Participants also had the possibility to leave free text comments in the form. Results: The participants rated a 16% increase in their well-being after using the rocking chair. The average rocking time was 33 minutes. The majority of the participants are diagnosed with bipolar disorder. Many participants preferred to use the rocking chair during a specific time frame every day. The content analysis resulted in five categories and the underlying meaning could be expressed by the theme "Moving emotions". No adverse effects were recorded during the study. Both the quantitative and qualitative analysis show positive results and there are no contradictions in the results. Conclusion: This study support the mental health nurse to recommend psychiatric patients to try rocking chair therapy as a way to increase well-being or reduce distress, it is also a method well suited for self-management. Each patient has his/her own preferences for using rocking chair therapy. The use of rocking chair therapy can easily be included in the patient’s personal care plan.
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The Control of Microstructural and Crystallographic Orientation via Ceramic Forming Methods for Improved Sintered TransparencyWilliam J Costakis (8787950) 01 May 2020 (has links)
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<p>Transparent alumina is a candidate material for ballistic applications where visible or infrared
wavelength transmission is required. However, the transparency of polycrystalline alumina can be
limited due to the rhombohedral crystal structure being inherently birefringent. Birefringence
causes light scattering at grain boundaries and is detrimental to the transparency. It has been shown
experimentally that the application of a high magnetic field during processing can lead to
crystallographic alignment and the reduction of birefringent light scattering. This alignment
method is effective but is limited in terms of scalability. This research addresses these limitations
through the use of simple and cost-effective shear and elongational forming processes such as
uniaxial warm pressing and direct ink writing (DIW) for the improvement of final sintered
transparency. To further support the improvement of these processes as alternatives and to evaluate
the possibility of using powder ratios to improve the alignment, this research will also investigate
the sintering behavior during hot-pressing of equiaxed and platelet powders.
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<p>Platelet ceramic-filled thermoplastic blends were developed and formed into sheets through
uniaxial warm pressing. The solids loading (30 – 40 vol.%) and platelet diameter (1.2 and 11μm)
were varied to compare effects on viscosity, percent reduction, and final alignment. All ceramic-
filled thermoplastic polymer blends exhibited pseudoplastic behavior. Crystallographic alignment
of green body samples was quantified by the orientation parameter (r) and grain misalignment
angle (full width at half maximum, FWHM) obtained from rocking curve analysis. Blends with
11μm diameter platelets displayed a higher temperature sensitivity constant, better flow properties,
and higher alignment compared to blends with 1.2μm diameter platelets. Optimal samples
produced with blends containing 30 vol.% of 11μm diameter platelets demonstrated an alignment
of r = 0.251 +/- 0.017; FWHM = 11.16° +/- 1.16°. A sample with optimal alignment was hot-pressed
to transparency and obtained an in-line transmission of 70.0% at 645nm. The final alignment of
this pre-aligned hot-pressed sample (r = 0.254 +/- 0.008; FWHM = 11.38° +/- 0.54°) improved when
compared to a non-pre-aligned sample (r = 0.283 +/- 0.005; FWHM = 13.40° +/- 0.38°).</p><p>Additionally, the use of direct ink writing, an additive manufacturing technique, as a viable
alignment process for producing transparent alumina was investigated. Highly loaded (> 54 vol.%) equiaxed alumina suspensions were developed with platelet additions ranging from 0-20vol.% of
the total solids loading. An increase in the amount of platelet powders from 5-20vol.% increased
the dynamic yield stress from 104Pa to 169Pa and decreased in the equilibrium storage modulus
from 17,036Pa to 13,816Pa. It was found that the DIW process significantly increased the
alignment in one orientation when compared to samples cast from the same suspensions and this
behavior may be connected to the rheological properties. Lastly, an optical analysis showed that
sample developed with 5vol.% platelet suspensions had higher in-line transmission values across
the visible spectrum when compared to samples developed with 20vol.% suspensions. A sample
cast from a 5vol.% platelet suspensions had the lowest grain alignment but possessed an in-line
transmission of 42.8% at 645nm, which was the highest of the samples produced in this study. An
optical loss analysis showed, that this sample has the lowest backwards scattering losses due to
residual porosity and this result was supported by the density data. It is suggested that the
alignment of the DIW samples is more complex and a more advanced texture analysis will need
to be conducted to properly characterize the grain alignment.</p><p>Lastly, the densification behavior of equiaxed and platelet powder ratios with no intentional
pre-alignment was investigated. An initial sintering investigation identified the optimum
maximum pressure selected for the hot-pressing process as 20MPa. Under the selected hot-
pressing parameters, the effects of 0, 25, 50, 75, and 100wt.% equiaxed powder additions on the
sintering behavior, optical properties, and grain alignment was investigated. The data showed that
an increase in the amount of equiaxed powders decreased the initial powder compact
displacements rate. Additionally, an increase in the wt.% equiaxed powders from 0wt% to 75wt%
decreases the in-line transmission from 70.9% to 40.2%, respectively at 645nm. Lastly, an increase
in the wt.% equiaxed powders from 0wt% to 75wt decreased the alignment from (r = 0.321 +/- 0.005;
FWHM = 16.26° +/- 0.40°) to (r = 0.509 +/- 0.022; FWHM = 34.63° +/- 2.61°), respectively.</p></div></div></div>
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