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A maioria dos silos existentes no mundo não apresenta condições ideais de operação devido ao insuficiente conhecimento das pressões, do fluxo e do grande número de variáveis que afetam o comportamento dos produtos armazenados. Isso explica também, a grande quantidade de acidentes e colapsos em silos. Uma análise dos principais códigos normativos indica a existência de divergências entre eles, principalmente quando se referem à determinação das pressões exercidas pelo produto armazenado sobre a estrutura, o mesmo ocorrendo entre as teorias propostas por pesquisadores. Este trabalho tem por finalidade apresentar um estudo teórico das pressões e fluxo em silos verticais esbeltos (h/d≥1,5) exercidas pelo produto armazenado. Para isso, um estado da arte das teorias de pressões e fluxo propostas pelos mais importantes pesquisadores e normas internacionais sobre o assunto foi desenvolvida. Como exemplo de aplicação, foram analisadas as pressões em um silo vertical esbelto com fundo cônico, para as situações de fluxo de massa e fluxo de funil, para dois produtos granulares. Com base nos resultados obtidos, foi elaborada uma proposta de norma brasileira para a determinação das pressões exercidas pelo produto armazenado para essas unidades, tendo em vista que o Brasil ainda não possui uma norma específica para o projeto e construção de silos. Além disso, foi desenvolvido um programa computacional de cálculo das pressões. / Silos are structures that usually present process and failures problems due to insufficient knowledge of bulk solids pressures and flow. An analysis of the principal international theories and standards shows divergences, mainly in the pressures determination due to the storage of bulk solids. This work presents a theoretical study of the pressures and flow in slender vertical silos (h/d≥1,5) due the storage of the bulk solids. An state of the art of the theories of pressures and flow proposed by the most important researchers and international standards on the subject is presented. As a practical example, the pressures were determined in a slender vertical silo with conical bottom, for mass and funnel flow patterns and for two granular materials. Based on the study, a proposal of Brazilian standard was elaborated for the determination of the pressures due the bulk solids for slender silos, considering that Brazil doesn't still have a specific standard for the design and construction of silos. A software for pressures determination was also developed.

O projeto seguro e econômico das estruturas de armazenamento é função das máximas ações impostas e da resistência destas estruturas de suportar tais ações, observadas as combinações mais desfavoráveis. Entre as ações consideradas nos cálculos dos silos horizontais (peso próprio, peso de equipamentos, vento, recalques diferenciais de apoios, impacto de veículos, explosões, etc), a de maior importância é a causada pelo empuxo dos produtos armazenados e que foi objeto de estudo nesta pesquisa. Este trabalho foi realizado em duas etapas, teórica e experimental, procurando avaliar estas ações com base em teorias e métodos de cálculo de diversos autores. Na tremonha do silo, as pressões foram avaliadas através do método de cálculo proposto por Safarian & Harris, da teoria de Walker e da Norma Australiana AS 3774. Nas paredes, foram avaliadas as pressões de acordo com as teorias de Airy, Reimbert & Reimbert, Coulomb e Rankine e da norma americana ANSI/96. Os modelos teóricos foram estudados e comparados com os resultados obtidos através de medições diretas das pressões em modelo piloto e silo horizontal em escala real com a determinação da relação entre as pressões verticais e horizontais (K). Dos resultados obtidos propõe-se um novo método de cálculo com base em um modelo empírico para a determinação das pressões horizontais nestas unidades. / The safe and economic design of storage structures is a function of the loads and of the strenght of these structures, considering unfavorable loads combinations. Among the loads considered in the calculations of the horizontal silos, the most important load is due stored products. Silos are usually designed on the basis of simple theory which is used to predict horizontal pressures on the walls and hoppers. The pressures generally depend on many factors including the physical properties of the stored materials, the flow pattern and also the method of operating the silo. This work is divided in two parts in order to evaluate these loads based in theories and international codes.The silo hopper was evaluate by Walker\'s theory and by AS 3774-1996 code. The silo walls was evaluete by theories of Airy, Rankine, Reimbert & Reimbert, Coulomb, Safarian & Harris and ANSI (1996) code. The theoretical models were studied and compared with the results obtained through pressure measurements in a real and a pilot silos. From the results we proposed a new empiric design method to evaluate the horizontal pressures in the silos wall.

There is a good deal of uncertainty and sensitivity in the results for wave impact. In a practical situation, many parameters such as the wave climate will not be known with any accuracy especially the frequency and severity of wave breaking. Even if the wave spectrum is known, this is usually recorded offshore, requiring same sort of (linear) transfer function to estimate the wave climate at the seawall. What is more, the higher spectral moments will generally be unknown. Wave breaking, according to linear wave theory, is known to depend on the wave spectrum, see Srokosz (1986) and Greenhow (1989). Not only is the wave climate unknown, but the aeration of the water will also be subject to uncertainty. This affects rather dramatically the speed of sound in the water/bubble mixture and hence the value of the acoustic pressure that acts as a maximum cutoff for pressure calculated by any incompressible model. The results are also highly sensitive to the angle of alignment of the wave front and seawall. Here we consider the worst case scenario of perfect alignment. Given the above, it seems sensible to exploit the simple pressure impulse model used in this thesis. Thus Cooker (1990) proposed using the pressure impulse P(x, y) that is the time integral of the pressure over the duration of the impact. This results in a simplified, but much more stable, model of wave impact on the coastal structures, and forms the basis of this thesis, as follows: Chapter 1 is an overview about this topic, a brief summary of the work which will follow and a summary of the contribution of this thesis. Chapter 2 gives a literature review of wave impact, theoretically and experimentally. The topics covered include total impulse, moment impulse and overtopping. A summary of the present state of the theory and Cooker’s model is also presented in Chapter 2. In Chapter 3 and Chapter 4, we extend the work of Greenhow (2006). He studied the berm and ditch problems, see Chapter 3, and the missing block problem in Chapter 4, and solved the problems by using a basis function method. I solve these problems in nondimensionlised variables by using a hybrid collocation method in Chapter 3 and by using the same method as Greenhow (2006) in Chapter 4. The works are extended by calculating the total impulse and moment impulse, and the maximum pressure arising from the wave impact for each problem. These quantities will be very helpful from a practical point of view for engineers and designers of seawalls. The mathematical equations governing the fluid motion and its boundary conditions are presented. The deck problem together with the mathematical formulation and boundary conditions for the problem is presented in Chapters 5 and 6 by using a hybrid collocation method. For this case, the basis function method fails due to hyperbolic terms in these formulations growing exponentially. The formulations also include a secular term, not present in Cooker’s formulation. For Chapter 5, the wave hits the wall in a horizontal direction and for Chapter 6, the wave hits beneath the deck in a vertical direction. These problems are important for offshore structures where providing adequate freeboard for decks contributes very significantly to the cost of the structure. Chapter 7 looks at what happens when we have a vertical baffle. The mathematical formulation and the boundary conditions for four cases of baffles which have different positions are presented in this chapter. We use a basis function method to solve the mathematical formulation, and total impulse and moment impulse are investigated for each problem. These problems are not, perhaps, very relevant to coastal structures. However, they are pertinent to wave impacts in sloshing tanks where baffles are used to detune the natural tank frequencies away from environmental driving frequencies (e.g ship roll due to wave action) and to damp the oscillations by shedding vortices. They also provide useful information for the design of oscillating water column wave energy devices. Finally, conclusions from the research and recommendations for future work are presented in Chapter 8.

Dans quelle mesure l'expression de nos opinions et nos comportements peuvent être affectés par le caractère public de la situation dans laquelle nous sommes ? Voilà la question qui a guidé ce travail de thèse. Nous plaçant dans la théorie des représentations sociales (RS, Moscovici, 1961) et plus particulièrement dans le cadre des effets de masquage dans l'expression de ces représentations (Guimelli, 1998), nous montrons, par la manipulation du contexte de réponse (public vs. privé), que les pressions normatives qui pèsent sur l'individu peuvent affecter non seulement son expression à propos d'un objet social mais également ses comportements liés à l'objet. De fait, ce travail s'organise autour de deux axes de recherches. Le premier axe, se centrant sur l'expression des RS, souligne, au travers de quatre recherches (n = 952), l'impact du contexte de réponse sur l'expression des individus. On constate que la publicité des réponses, augmentant le niveau de pressions normatives, amène les sujets à mettre en place des stratégies de masquage et d'affichage liées à la désirabilité sociale. Le second axe, s'intéressant à l'impact du contexte public sur les comportements des individus, regroupe deux recherches (n = 371) dans lesquelles on propose aux participants de réaliser la tâche du dilemme itératif du prisonnier. Ces deux recherches mettent en évidence d'une part que les éléments masqués des représentations ont un impact sur les comportements des individus et d'autre part que ces mêmes comportements sont eux aussi dépendants du contexte et plus précisément des enjeux normatifs qui le caractérisent. / To what extent the public aspect of a given situation can influence the expression of our opinions and behaviors is the very question which has been leading this work of thesis. Referring to the theory of social representations (SR, Moscovici, 1961) and more precisely to the concept of masking effects described in the expression of these representations (Guimelli, 1998), we will show that because of the manipulation of the answering context (public vs. private) the normative pressures weighing on an individual can influence, not only his/her expression linked to a social object, but also his/her behaviors connected to this object. Actually this work gets organized around two main lines of research: The first part focuses on the expression of social representations and highlights the impact of the answering context on the expressions used by a group of individuals (study led through four researches n=952). It will be noticed that the public aspect of answers increases the level of normative pressures and therefore brings the subjects to set up masking and displaying strategies which directly results from a social desirability. The second part deals with the impact of the public context on the behavior of individuals (study led through two researches n=371). In this main line, the participants are invited to achieve a task called “the iterative dilemma of the prisoner”. Those two examples will bring to light, one the hand, that masked elements of representations have an impact on the individual behaviors, and on the other hand, that the very same behavior is also dependent of the context and more precisely of the normative characteristics which are at stake.

“Real time grouting control method” är ett koncept för att övervaka och bedöma spridningen av injekteringsbruk under injektering. Målet är att kunna använda penetrationsavstånd som stopkriterium och att kunna övervaka hur injekteringsarbetet fortskrider i realtid, vilket skulle göra injekteringsarbetet mer tids- och kostnadseffektivt. Teorin har prövats med data från ett tunnelprojekt i Sverige med kristallint berg från prekambrium-eran, och med data från dammprojekt i Iran och Laos med sedimentärt berg, samtliga med lovande resultat. RTGC-teorin har nyligen vidareutvecklats, där bedömningar och begränsningar angående jacking föreslås, utifrån en kombination av injekteringstryck och spridning av injekteringsbruk. Teorin har  tvecklats både för elastisk jacking, där deformationer kan kompenseras för, och för plastisk jacking, där deformationerna är permanenta. Effekterna av höga tryck och jacking kan uppskattas och de eventuella negativa konsekvenserna kvantifieras. Mer specifikt ligger fokus på vilken påverkan sprickdeformationer kan ha på penetrationsavståndet och på transmissiviteten i en spricka. Syftet med detta examensarbete har varit att undersöka vilka effekter höga injekteringstryck har på injekteringsprocessen av en tunnel med avseende på jacking. I examensarbetet har teorin för RTGC använts för att analysera data från ett järnvägstunnelsprojekt i Norge, där betydligt högre injekteringstryck än i Sverige generellt sett används. Teorin har kunnat appliceras på data framgångsrikt, även om mindre anpassningar varit nödvändiga. Orsaken till anpassningarna är att teorin främst är utvecklad för ett mer eller mindre konstant injekteringstryck, samtidigt som ett varierande injekteringstryck i viss utsträckning använts i det norska projektet. Resultaten tyder på att det skulle vara möjligt att spara både tid och pengar med hjälp av RTGC, genom att minska åtgången av både tid och injekteringsbruk. Resultaten antyder även att höga injekteringstryck kan orsaka betydande jacking om geologin och sprickornas orientering och längd är ogynnsamma. Om och i vilken utsträckning jackingen påverkar den slutliga tätningen av bergmassan har emellertid inte kunnat studeras i detta projekt, då data kring inläckage ej varit tillgänglig vid genomförandet av analysen. Vidare visas, trots vissa antaganden och förenklingar i den geologiska modellen, att denna teoretiska modell möjliggör en bedömning av effekterna som injekteringstrycket har på det slutliga resultatet. Detta bör kunna användas för att välja ett optimalt injekteringstryck. / The “Real Time Grouting Control Method” is a concept for governing the grout spread during a grouting operation. The goal is to be able to use the penetration length as stop criterion and to be able to monitor the progress of the grouting operation in real-time, which would make grouting operations more efficient in terms of time and cost. The theory has been tested with data from tunnelling projects in Sweden with pre-cambium rock, and with data from dam projects in Iran and in Laos with sedimentary rock, all with promising results. Recently there have been developments in the RTGC-theory that propose jacking limits based on a combination of grout pressure and spread of grout, both for elastic jacking, where deformations can be compensated for, and ultimate jacking, where deformations are permanent. With the theory, the effects of high pressures and elastic jacking can be assessed, and the negative consequences of elastic jacking can be quantified. Specifically, the  focus is on the effect that fracture deformation may have on the distance that the grout penetratesinto a fracture, and on the transmissivity of a fracture. The aim of this thesis is to evaluate what effects high grouting pressures may have on the grouting process with respect to jacking. To obtain this, the theory is used to analyse data from a railway tunnel project in Norway, where considerably higher grouting pressures than in Sweden are used. The application of the theory has been successful, even though some minor adaptions have been necessary. The reason for the adaptions is that the RTGC-theory is developed for a more or less constant grouting pressure, while a varying pressure to some extent has been applied in the Norwegian project. The results suggest that using RTGC could save time and money by reducing grouting time and grout volume. The results also suggest that the high grouting pressures may cause considerable jacking if the geology and fracture situation is unfavourable. If and to what extent the jacking affects the final tightness of the rock mass has however not been possible to determine, given that data regarding measured leakage has not been available at the time for this analysis. It is shown that despite assumptions and simplifications in the geological model, using this theoretical approach enables the estimation of the effect that the grouting pressure has on the outcome of the performed grouting, arguably allowing for the optimum grouting pressure to be selected.

Increasing diastolic dysfunction (DD) grade is associated with increased heart failure (HF). Patients with preserved ejection fractions and grade 1 DD may have left atrial dilatation, e′ < 8 cm/sec, increased left ventricular (LV) mass, or variable E/e′ ratios. The aim of this study was to test the hypothesis that LV hypertrophy or E/e′ ratio > 8 may be associated with a greater incidence of HF. Methods Two hundred twelve patients with grade 1 DD and ejection fractions > 50% were retrospectively studied. Group 1 comprised 108 patients with E/A ratios < 0.8, without LV hypertrophy, e′ < 8 cm/sec, and E/e′ ratios < 8. Group 2 comprised 104 patients with LV hypertrophy or E/e′ ratios > 8. Patients with incident HF and valvular or coronary disease were excluded. Using two-dimensional Doppler echocardiography, LV and left atrial volumes and transmitral spectral and tissue Doppler were analyzed. Medical records were examined for laboratory data, HF admissions, and all-cause mortality from 2004 to 2012. Results Despite similar ejection fractions, patients in group 2 had greater LV and left atrial volumes, LV mass index values, and E/e′ ratios (P < .01 for all). HF incidence was greater in group 2 (30 vs 4, P < .001). Combined HF or all-cause mortality was greater in group 2 (46 vs 14, P < .001). Multivariate analysis revealed that HF was associated with E/e′ ratio (P < .0001), systolic blood pressure (P = .0123), and LV mass index (P = .042). Combined HF or all-cause mortality was associated with E/e′ ratio (P < .0001), LV mass index (P = .009), and lower calcium channel blocker use (P = .0011). Conclusions HF alone or HF and all-cause mortality were increased in patients with grade 1 DD in the presence of LV hypertrophy or elevated LV filling pressures.

Thesis (M.A. (Clinical Psychology)) --University of Limpopo,2019 / Sociocultural pressures, including the thin-ideal internalization, and other aspects of self-objectification, are associated with body dissatisfaction. However, there is limited research regarding the association between self-objectification and engagement in health related behaviours among African females. A quantitative study was conducted with a sample of 411 female African university students from the University of Limpopo, South Africa to investigate the relationship between internalisation of sociocultural beauty standards and body dissatisfaction and engagement in health related behaviours. The study further explored whether cultural identity would moderate the relationship between internalisation of socio-cultural beauty standards and both body dissatisfaction and engagement in health related behaviours. Structural equation modelling (SEM) suggested that internalization of socio-cultural beauty standards significantly predicted students’ body satisfaction. No statistically significant relationship was found between internalization of socio-cultural beauty standards and engagement in health related behaviours. Also, cultural identity did not moderate the relationship between self-objectification and both body dissatisfaction and engagement in health related behaviours. This being a single study, further research is required to determine the relationship between the variables.

While many large firms have implemented Big Data Analytics (BDA), it is unclear whether Small and Medium-sized Enterprises (SMEs) are ready to adopt and use this technology. This study investigates BDA implementation from the perspective of both managers and data analysts. Managers are mostly influenced by factors from the external environment, while data analysts are mostly influenced by technological factors. Hence, in this study, it is contended that managers imitate the behavior of external institutions, while data analysts mostly evaluate technology characteristics in the process of BDA implementation. The present study draws on institutional, organizational change, and diffusion of innovation theories through the lens of an imitation-evaluation perspective to investigate readiness and adoption behaviours. Accordingly, a theoretical research model was developed to explore the salient variables that impact organizational and data analysts’ readiness for implementing BDA in SMEs. To test these assertions, two surveys were conducted with 340 responses including 170 managers and 170 data analysts in SMEs in North America. The findings demonstrate that: (1) an imitation perspective plays a significant role in organizational readiness to adopt BDA; (2) uncertainty in big data technologies can intensify the effect of normative pressures on organizational readiness; (3) big data complexity, trialability, and relative advantage impact data analysts’ readiness to use big data analytics; and (4) the influence of relative advantage is attenuated by the high level of data analytics skills. These findings provide valuable contributions to the theory and practice of BDA implementation in SMEs in the BDA adoption and use literature. / Dissertation / Doctor of Business Administration (DBA)

Background: Marketing communication is the process of communicating with the customer, this is all communicative materials that are produced by the firm in order to influence the consumer. Regulations are all the rules, instructions, memos issued by a market authority that dictate the ways a firm may present their brand. Important to gain the firm's understanding of regulations and the ways to work within them. Purpose: The purpose of this paper is to explore how external regulations impact marketing communications from the firm's perspective. Research Question: How do companies understand the impact of regulations on marketing communications and work within them? Theoretical framework: The theoretical framework was established using the marketing communications mix in combination with institutional theory, investigating the research question through the lens of institutional pressures. Methodology: This study used a qualitative and inductive approach, using a case study on the Canadian cannabis industry. Using purposive sampling and semi-structured interviews with three respondents to collect data. Analysing the collected data with a systematic coding process to objectively interpret meaning from the respondents perspectives. Conclusion: The conclusions of this paper were threefold. First, coercive pressure is the most observed form of isomorphic pressure as there has not been enough industry maturity to establish normative pressures which leads to a hesitancy of mimetic behaviour. Secondly, there are multiple layers of institutional pressures from various dominant actors within the shared organisational environment, which leaves firms feeling incapable of marketing. Lastly, personal selling is the most effective tool from the marketing communication mix due to the impacts of the regulations and the infancy of the market.  Contribution: Study confirms the findings of Asquith’s (2021) research. Multiple layers of institutional pressure in the industry. Infant markets are more susceptible to coercive pressure.