985 resultados para property structure relationship


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Pipelines extend thousands of kilometers across wide geographic areas as a network to provide essential services for modern life. It is inevitable that pipelines must pass through unfavorable ground conditions, which are susceptible to natural disasters. This thesis investigates the behaviour of buried pressure pipelines experiencing ground distortions induced by normal faulting. A recent large database of physical modelling observations on buried pipes of different stiffness relative to the surrounding soil subjected to normal faults provided a unique opportunity to calibrate numerical tools. Three-dimensional finite element models were developed to enable the complex soil-structure interaction phenomena to be further understood, especially on the subjects of gap formation beneath the pipe and the trench effect associated with the interaction between backfill and native soils. Benchmarked numerical tools were then used to perform parametric analysis regarding project geometry, backfill material, relative pipe-soil stiffness and pipe diameter. Seismic loading produces a soil displacement profile that can be expressed by isoil, the distance between the peak curvature and the point of contraflexure. A simplified design framework based on this length scale (i.e., the Kappa method) was developed, which features estimates of longitudinal bending moments of buried pipes using a characteristic length, ipipe, the distance from peak to zero curvature. Recent studies indicated that empirical soil springs that were calibrated against rigid pipes are not suitable for analyzing flexible pipes, since they lead to excessive conservatism (for design). A large-scale split-box normal fault simulator was therefore assembled to produce experimental data for flexible PVC pipe responses to a normal fault. Digital image correlation (DIC) was employed to analyze the soil displacement field, and both optical fibres and conventional strain gauges were used to measure pipe strains. A refinement to the Kappa method was introduced to enable the calculation of axial strains as a function of pipe elongation induced by flexure and an approximation of the longitudinal ground deformations. A closed-form Winkler solution of flexural response was also derived to account for the distributed normal fault pattern. Finally, these two analytical solutions were evaluated against the pipe responses observed in the large-scale laboratory tests.

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Thermal and fatigue cracking are the major pavement distresses that contribute to a drastic reduction of the pavement’s service life and performance in Ontario. Chemical oxidation and hardening of asphalt binders deteriorates its physical properties since physical properties of asphalts depend on its chemical composition. This thesis is aimed to establish a relationship between physical and chemical properties of asphalt binders. A secondary objective is to show the strong correlation between CTOD and temperature. All recovered and straight Ministry of Transportation of Ontario (MTO) samples were investigated using conventional Superpave® test method dynamic shear rheometer (DSR) as well as improved MTO test methods such as extended bending beam rheometer (eBBR) and double-edge-notched tension (DENT) test. DENT test was conducted for all Ontario contract samples at three different temperatures based on their performance grade after three hours of thermal conditioning and compared the results in terms of essential work of fracture, plastic work of fracture and CTOD at different temperatures. Good correlation exists between CTOD and temperature according to the DENT data. X-ray fluorescence (XRF) analysis was conducted to detect the presence of heavy metals such as zinc and molybdenum believed to have originated from waste engine oil. Fourier transform infra-red spectroscopy (FTIR) was performed to determine the abundance of functional groups such as carbonyl, sulfoxides, polyisobutylene, etc. XRF and FTIR analysis confirmed that most of the samples contain waste engine oil and/or oxidized residues, which is believed to be a root cause of premature pavement failures.

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Background: It is well known that sprint interval training (SIT), induces significant increases in peak oxygen uptake (VO2peak) at the group level. However, there have been only a few studies that have addressed the variability of VO2peak response following SIT, and precise mechanism(s) that may explain individual magnitude of response are unknown. Purpose: Therefore, the purpose of this thesis was to: 1) examine the inter-individual variability of the VO2peak response following SIT, 2) to inspect the relationship between changes in both central and peripheral measures and changes in VO2peak, and 3) to assess if peripheral or central adaptations play a role in whether an individual is a high or low responder with respect to VO2peak. Subjects: Twenty-two young, recreationally active males (age: 20.4 1.7 years; weight: 78.4 10.2 kg; VO2peak: 3.7 0.62 L/min) Methods: VO2peak (L/min), peak cardiac output (Qpeak [L/min]), and peak deoxygenated hemoglobin (HHbpeak [mM]) were measured before and after 16 sessions of SIT (Tabata Protocol) over four weeks. Peak a-vO2diff was calculated using a derivation of the Fick equation. Results: Due to a systematic error, HHbpeak could not be used to differentiate between individual responses. There was a large range of VO2peak response from pre to post testing (-4.75 to 32.18% change) and there was a significant difference between the Low Response Group (LRG) (n=8) and the High Response Group (HRG) (n=8) [f(1, 14)= 64.27, p<0.001]. Furthermore, there was no correlation between delta () VO2peak and Qpeak (r=-0.18, p=0.46) for all participants, nor was there an interaction effect between the Low and High Response Groups [f(1,11)=0.572, p=0.47]. Lastly, there was a significant correlation between VO2peak and peak a-vO2diff [r=0.692, p<0.001], and a significant interaction effect with peak a-vO2diff [f(1, 14)= 13.27, p<0.004] when comparing the HRG to the LRG. Conclusions: There was inter-individual variability of VO2peak response following 4 weeks of SIT, but central adaptations did not influence this variation. This suggests that peripheral adaptations may be responsible for VO2peak adaptation.

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Sexual scripts—the definitions and expectations that individuals hold for sexual interactions—are thought to play an important role in the maintenance of sexual well-being. Sexual scripts can be rigid or flexible, and they can be concordant or discordant between members of a couple. Sex therapists support sexual script flexibility for maintaining sexual and relationship satisfaction when couples are navigating sexual issues. However, empirical research examining the role of sexual script flexibility and the degree of script concordance/discordance in couples’ sexual well-being has been limited, due in part to the limited measures available. Furthermore, within the existing research, there has been an unfortunate tendency to exclude individuals in same-gender relationships – perpetuating the long-standing knowledge gap in the literature on positive sexuality in diverse relationships. To address these gaps in the literature, we conducted a series of online studies that recruited individuals in diverse relationships. A measure of individual sexual script flexibility in response to sexual issues was developed (Chapter 2); in addition, the structure of an existing measure assessing couple sexual scripts in response to a sexual issue was evaluated (Chapter 3). Chapter 4 examined how individuals in diverse relationships compared on measures of individual sexual script flexibility and on couple sexual scripts. Findings suggest that there are more similarities than differences across diverse couples. Chapter 5 explored how flexibility in an individual’s approach to sexual issues relates to sexual well-being, specifically by assessing sexual communication and partner responses as mediators. Results suggest that individual sexual script flexibility relates to sexual well-being through reciprocal partner processes. Collectively, this research program suggests that more similarities than differences exist between individuals in same- and mixed-gender relationships, and that partners are important to consider in the relationship between individual sexual script flexibility and sexual well-being. These findings have implications for sex and couple therapy; these results emphasize the importance of interventions that target both members of the couple, and further our understanding of sexuality in same- and mixed-gender relationships.

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Previous studies about the strength of the lithosphere in the Iberia centre fail to resolve the depth of earthquakes because of the rheological uncertainties. Therefore, new contributions are considered (the crustal structure from a density model) and several parameters (tectonic regime, mantle rheology, strain rate) are checked in this paper to properly examine the role of lithospheric strength in the intraplate seismicity and the Cenozoic evolution. The strength distribution with depth, the integrated strength, the effective elastic thickness and the seismogenic thickness have been calculated by a finite element modelling of the lithosphere across the Central System mountain range and the bordering Duero and Madrid sedimentary basins. Only a dry mantle under strike-slip/extension and a strain rate of 10-15 s-1, or under extension and 10-16 s-1, causes a strong lithosphere. The integrated strength and the elastic thickness are lower in the mountain chain than in the basins. These anisotropies have been maintained since the Cenozoic and determine the mountain uplift and the biharmonic folding of the Iberian lithosphere during the Alpine deformations. The seismogenic thickness bounds the seismic activity in the upper–middle crust, and the decreasing crustal strength from the Duero Basin towards the Madrid Basin is related to a parallel increase in Plio–Quaternary deformations and seismicity. However, elasto–plastic modelling shows that current African–Eurasian convergence is resolved elastically or ductilely, which accounts for the low seismicity recorded in this region.

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In this study, we investigated the relationship between vegetation and modern-pollen rain along the elevational gradient of Mount Paggeo. We apply multivariate data analysis to assess the relationship between vegetation and modern-pollen rain and quantify the representativeness of forest zones. This study represents the first statistical analysis of pollen-vegetation relationship along an elevational gradient in Greece. Hence, this paper improves confidence in interpretation of palynological records from north-eastern Greece and may refine past climate reconstructions for a more accurate comparison of data and modelling. Numerical classification and ordination were performed on pollen data to assess differences among plant communities that beech (Fagus sylvatica) dominates or co-dominates. The results show a strong relationship between altitude, arboreal cover, human impact and variations in pollen and nonpollen palynomorph taxa percentages.

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The recent crisis of the capitalistic economic system has altered the working conditions and occupations in the European Union. The recession situation has accelerated trends and has brought transformations that have been observed before. Changes have not looked the same way in all the countries of the Union. The social occupation norms, labour relations models and the type of global welfare provision can help underline some of these inequalities. Poor working conditions can expose workers to situations of great risk. This is one of the basic assumptions of the theoretical models and analytical studies of the approach to the psychosocial work environment. Changes in working conditions of the population seems to be important to explain in the worst health states. To observe these features in the current period of economic recession it has made a comparative study of trend through the possibilities of the European Working Conditions Survey in the 2005 and 2010 editions. It has also set different multivariate logistic regression models to explore potential partnerships with the worst conditions of employment and work. It seems that the economic crisis has intensified changes in working conditions and highlighted the effects of those conditions on the poor health of the working population. This conclusion can’t be extended for all EU countries; some differences were observed in terms of global welfare models.

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Innovation is a fundamental part of social work. In recent years there has been a shift in the innovation paradigm, making it easier to accept this relationship. National and supranational policies aimed at promoting innovation appear to be specifically guided by this idea. To be able to affirm this hypothesis, it is necessary to review the perception that social workers have of their duties. It is also useful to examine particular cases that show how such social innovation arises.

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El presente trabajo tiene como objetivo evaluar hasta qué punto las cadenas de televisión generalista en España adoptan estrategias de comunicación coherentes, sólidas y atractivas a la hora de construir una relación con los espectadores en su continuidad. Para ello, se aplica un análisis del discurso verbal a una muestra de piezas de continuidad televisiva de La1, Antena3, Telecinco y TV3. El análisis de las características enunciativas de las piezas muestra que, más allá de sus especificidades (en relación a la proximidad con los espectadores, su grado de directividad o su vinculación con ciertas identidades), los discursos de la continuidad de las cadenas requieren mayor coherencia y capacidad de diferenciación, más aún en un contexto de pérdida de prominencia social de la televisión generalista.

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Las relaciones entre los gabinetes de Comunicación de los clubes de fútbol y los periodistas deportivos se enmarcan en el modelo de Gieber y Johnson (1961) por el que el hecho de que ambos compartan objetivos comunes, donde los gabinetes de Comunicación necesitan que los medios publiquen determinadas informaciones y los periodistas precisan de noticias que publicar, provoca una pérdida de independencia por parte de los periodistas, ya que necesitan a esos departamentos como fuentes. En la actualidad, los departamentos de Comunicación de los clubes de fútbol, como el del FC Barcelona, se han constituido en gatekeepers. Esto ha acentuado las históricas diferencias que existen entre los periodistas y los profesionales de la comunicación corporativa, incrementado por el control informativo de estos departamentos lo que provoca constantes tensiones entre ambos.