Natural tropical deciduous forest (TDF) is considered with a medium to small height (< 15 m). Particularly, in Mexico TDF shows a remnant of 36.2% of primary forest driving changes in the structure and species composition. This vegetation in Mexico is mainly transformed into grassland for cattle raising, and agriculture, primarily for self-consumption. More information about the ecology and the social pressures on this vegetation can be seen in Chapter I. The general methods, including sampling allocation and collection, characteristics of the study site, as well the procedure of the research proposal is presented in Chapter II. The main aim of this thesis is to improve the accuracy of predictions of net carbon emissions and the spatial distribution of AGB in the Tropical Deciduous Forest of Mexico. To address this aim, it is important to take into consideration the forest structure, spatial patterns and processes in a natural forest in a multi-scale analysis; also, it is necessary to characterize the spatial socio-economic drivers that influence current AGB losses. With the understanding of such elements, it is possible to reconstruct the potential carbon stocks and estimate the allocation of net carbon emissions due to deforestation and forest degradation. This study shows that it is possible to count net carbon emissions caused by deforestation and forest degradation at a landscape scale. To come to such estimates, it was necessary to reduce the different sources of uncertainty. Chapter III explores different elements that drive the AGB allocation in a mature forest. The AGB in the mature forest was considered as the potential AGB that the forest could get assuming that it has reached its steady state. Different field sampling strategies and allometric equations were evaluated to account for uncertainty in the AGB estimations. The results showed that small sampling design (300-400 m2) and large-sized plots (4 ha) produce the same tree distribution for trees: ≥30 cm in DBH as well as in AGB. These results contradict what has been reported for others (Chave et al., 2004 and 2005) when they refer to the general definition of tropical forest. However, those other studies referred to forests with a much higher precipitation and which can be classified as tropical rain (perennial) forest (Chave et al., 2004). In the tropical deciduous forest, the kind considered in this study, AGB tends to be allocated in small-sized trees. Diverse biophysical characteristics that may drive AGB allocation were considered over different spatial scales. Water stress was the main driver for AGB density at different spatial scales. Nutrients showed little significance to explain AGB as other studies have suggested in secondary forests and/or chronosequences. With this understanding, Chapter IV shows the use of different multi-variable models. Parsimonious models were the result of the variables selection and sensitivity test. Most of the methodologies showed a better performance to explain AGB allocation than a null-model. However, when they were contrasted with independent observations over different spatial resolutions, it was possible to conclude that only GLM was capable of reproducing the spatial patterns, and its estimations were close to observations. Nevertheless, some observations with very large AGB densities were underestimated by the model. This underestimation was related to the presence of few very large-sized trees. These two chapters depict the possibility of accounting for the potential AGB, and the uncertainty, namely whether the landscape could reach it with the absence of human disturbance. Once the potential AGB map was built and validated, it was transformed to carbon stock, using a local carbon concentration estimate. This potential carbon stock map was contrasted to the different available maps of current carbon stocks. Consequently, it was possible to estimate net carbon emissions due to deforestation and forest degradation (Chapter V), suggesting that the general models tend to agree in the total carbon loss. However, there are some spatial discrepancies in the magnitudes of change. Main differences between maps can be reduced by diverse socio-ecological constraints that dominate the landscape. This is important because it may be possible to make future adjustments that would reduce variability, enabling more accurate AGB estimations. However, to individually account for deforestation and forest degradation, more detailed sources of local information are necessary, such as socio-economic variables. Therefore models with a bottom-up perspective would lead to a better understanding and representation of the landscape. Finally, the growing rural population will have larger demands for wood and food, so while remote or protected areas may have the potential for storing high AGB, forest close to settlements and access routes are likely to continue being disturbed, unless affordable alternatives are available for the sustainable use of the forest. In conclusion, the estimation of spatial heterogeneity of AGB in the landscape is of great importance when measuring carbon stocks and ecological dynamics. Various elements influence the AGB allocation in the mature forest. Among all of them, water availability played the most decisive part of various spatial scales. My models support the hypothesis that water availability plays the major role in explaining AGB in Mexico on a local, sub-regional and landscape scale. Model selection produced contrasting AGB estimates and patterns. Moreover, the results of this study tell us that there is not a clear consensus among various current AGB maps. However, they also show that with a multi-model comparison it is possible to identify carbon emissions drivers and calculate total carbon emissions due to forest disturbances. Socio-economic variables played the major role in explaining AGB losses. Therefore, future studies should look into a bottom-up approach for a better understanding and representation of current AGB.

This study provides two empirical studies in market-based accounting research. One study focuses on using out-of-sample valuation errors to evaluate various estimation approaches for firm-valuation models. The second empirical study uses portfolio analysis to evaluate an empirical accounting-based firm valuation model developed in the UK context.The first study uses out-of-sample valuation errors as an alternative metric capturing the effectiveness of various estimation approaches in generating reliable estimates of coefficients in accounting-based valuation models and, accordingly, less valuation bias and higher valuation accuracy. Valuation bias is expressed as the mean proportional valuation error, where estimated market value less the actually observed market value divided by the actual market value is the proportional valuation error, and valuation accuracy is measured by both the mean absolute and the mean squared proportional valuation error. We find that deflating the full equation including the constant term of the undeflated model and, hence, estimating without a constant term in the deflated model provides less bias and more accurate value estimates relative to including a constant term in the regression equation. Also estimating the valuation model on high- and low-intangible asset firms separately, instead of pooling the full sample for estimation, provides better performance in all cases. As expected, the results suggest that an extended model including the main accounting variables found to be associated with market value in the UK is better specified than a benchmark model, widely adopted in prior research, where market value is regressed on book value and earnings alone. Inclusion of 'other information' also seems to improve the performance of the models. However, there is no clear evidence that one particular deflator out of the five we investigate outperforms the others, although book value and opening and closing market value appear to generally perform better than sales and number of shares.The second empirical study tests for the existence of a 'mispricing' effect associated with accounting-based valuation models in the UK. It investigates a specific firm valuation model where market value is expressed as a linear combination of book value, earnings, research and development expenditures, dividends, capital contributions, capital expenditures and other information. All these accounting variables have been found value-relevant in prior studies in the UK. Firms are ranked by in-sample proportional valuation errors. Results show that although firms in the higher rank deciles tend to have higher abnormal returns than firms in the lower rank deciles, the difference between the two extreme portfolios (or the hedge returns) is statistically insignificant. As a consequence, accounting-based valuation models do not seem to provide superior estimates of intrinsic value to market values. We can conclude that the UK stock market is semi-strong form efficient, in the sense that it does not appear to be possible to generate positive abnormal returns based upon publicly available accounting information embedded in the valuation models studied.

To build multi story buildings out of timber is of a common interest in the building sector. Timber as a building material has many profits, such as the low cost, the availability and the ability to recycle it, the low carbon footprint and the workability. Although, when it comes to fire protection of buildings with a timber based structure there are challenges regarding prevention of the spread of fire while timber surface is exposed to fire. There have been cases in which timber buildings have caught fire leading to severe fire spread and ruined buildings. One example concerns a student modulus accommodation in Luleå that caught fire in august 2013. The fire started on the fourth floor after which a vertical fire spread occurred in concealed spaces between the volume modules. According to the fire investigation lack of knowledge regarding performance of detailed building solutions has led to the poor fire performance of the building. This master thesis mainly consists of a model scale tests that is prepared and performed according to the standard EN 1363-1. The purpose of the test is to investigate the performance of various cavity barriers exposed to fire. The main objective is to examine which temperatures that can be expected at different positions at various cavity barriers when using model scale test as a test method. There are two main kinds of cavity barriers: barriers that are airtight and closed inside the voids of the construction; and ventilated barriers. The most common cavity barriers are the ones that are airtight and closed. The material can be solid wood, gypsum board or mineral wool. The installation areas for these cavity barriers are anywhere, besides where the concealed spaces shall be ventilated and in every joint that shall be sealed using sealant. The ventilated cavity barriers are mounted in concealed spaces where the ventilating function is provided. These concealed spaces are often situated in, for example, ventilated attics, facades and roofs. The purpose of the ventilated barriers is to maintain the air flow in the cavity during regular conditions but also to form a protecting barrier between fire compartments when exposed to fire. The model scale test includes test apparatuses such as thermocouples and a fire resistance furnace with plate thermometers and burners. In addition, a test rig consisting of test specimens and the products to be tested are essential.  In this report, two model scale tests have been performed and prepared according to EN 1363‑1. The test period endured for four hours and the thermocouples measured the temperatures during the whole time. During the first hour the test specimens were exposed to the standard ISO 834 fire curve by controlling the burners in the furnace. After one hour the burners were turned off and the specimens were no longer exposed to fire. The measurements of the temperatures continued during three more hours. After the first two of these three hours the furnace was opened to confer more oxygen in the purpose to record any changes in the temperatures. Results of the performed experiments have indicated parameters that affect the performance of the cavity barriers. The cavity surface itself has an influence to the fire spread. The number of barriers in the cavity and the material properties of the material that is used as the cavity barrier lead to the different protection by those cavity barriers. Some of the tested barriers were plastic covered, which had effect on the performance of the cavity barriers. The dimensions of the barriers, moreover the width and the thickness, are important parameters for the proper function of the barrier. The test results indicate that glowing combustion occurs in the cavity between various cavity barriers.  It can be seen that the temperature rises when the furnace is opened. This indicates the appearance of smouldering since the combustion increases when the amount of oxygen increases, which leads to a temperature rise. Furthermore, the appearance of smouldering (glowing combustion) can be indicated by the observation of the damages of the specimens after the test. The temperatures that may be expected at the unexposed side of the cavity barrier depend on the surface material of the cavity, dimensions, and the material of the cavity barriers. Smouldering is a consequence of the temperature rise in closed cavities between cavity barriers. The performed test endured for approximately four hours and this indicates that fires in cavities can stay for a long time. To ensure the performance of various cavity barriers and verification by a model scale test it is important to perform further experiment and analyses to investigate the effects of the various parameters. To ensure the effectiveness of the performance of the cavity barriers they should be tested in cavities with various widths and various heights. Further investigation of the risk for smouldering is needed with measuring the amount of oxygen and the pressure.

Previous research indicates that there are a number of factors that contribute to one’s propensity to engage in cheating. The purpose of the current study was to explore trends in relationships, cheating, and attraction, and to determine the extent to which electronic media influences these. In a self-report survey of 265 participants (217 females; M age 20.9; SD 1.5), it was found that sociosexual orientation and impulsivity were related to past and current cheating, and increased quality of alternatives, diminished commitment and dissatisfaction were associated with current cheating. Impulsivity, quality of alternatives and diminished commitment were also found to be associated with electronic extradyadic intimacy. Finally, diminished commitment and increased perceived quality of alternatives were found to be associated with attraction to close cross-sex friends. Implications for research and clinical practice are discussed.

This thesis is an architectural study surveying on miniature parks and miniature models exhibited in them and particularly focuses on Miniaturk - the first miniature park of Turkey- located in Istanbul. It is established as an environment containing a group of miniature models of buildings and landscapes, which display the variety, and richness of the cultural tradition of the previous and contemporary Anatolian civilizations, and especially Ottoman grandeur. In this study, it is argued that Miniaturk stands as a hybrid category between a museum, a public park and entertainment centre. Miniaturk is also conceived as an architectural environment providing a possible ground to discuss the conceptions, misconceptions and presuppositions about architecture in the popular realm and in the professional and disciplinary framework. Thereby, Miniaturk is investigated through the processes of its production including the initial design idea and all the stages of its construction. This study also tries to discuss the miniature models from different points of view. Whether they are considered as tools of architectural representation or not by the professionals, the popularity and the communicative advantage of these models can be used to arouse interest in the cultural and historical heritage as well as the contemporary architecture. The daily life of man on the street is strictly connected with architecture / therefore Miniaturk requires recognition as an environment for realization of these connections and relations.

In the present study, possible scale effects on the formation of air-entraining vortices at horizontal intakes are studied experimentally. Basic dimensionless parameters that govern the onset of vortices at a horizontal intake in a model and a prototype are stated by dimensional analysis. Series of experiments are conducted on four intake pipes of different diameters located in a large reservoir. The relationship of critical submergence ratio with other dimensionless parameters is considered for a given Froude number and it is found out that the critical submergence ratio is affected by model length scale ratio and its natural result of side-wall clearance ratio and Reynolds number differences between model and prototypes. It is observed that, side-wall clearance ratio is not effective on the critical submergence ratio after it exceeds about 6. In addition to this, Reynolds number limit, beyond which viscous forces do not affect the vortex flow, is found out to be increasing with the increase in Froude number. An empirical relationship, which gives the critical submergence ratio as a function of Froude number, side-wall clearance ratio and Reynolds number is obtained by using data collected in the experiments.

This research consists of two main parts: development of a rock expert system (RES) as an easy-to-use and effective tool for evaluating rock properties, and modification and utilization of the three-dimensional Particle Flow Code (PFC3D) to analyze rock behavior. Because of different reasons, it is often difficult to obtain the rock property values directly. As an alternative, typical values and empirical correlations are often used to evaluate the rock property values. However, the typical values and empirical correlations come in various forms and are scattered in different sources. It is often difficult, time-consuming or even impossible for an engineer to find appropriate information to estimate the required rock properties. So in the first part of the research, the RES was developed as an easy-to-use and effective tool for evaluating rock properties by conducting detailed review and evaluation of well determined values and empirical correlations of rock properties in the published literature, and developing a central database and data application tools. The study of RES demonstrates the storage of rock property values and correlations is strongly applicable and the web based data application tool is effective to use and easy expandable. Considering its granular nature, the discrete element method (DEM) has been widely adopted to analyze the mechanical behavior of rock. The Particle Flow Code (PFC) is one of the most popular DEM softwares. The basic idea of PFC is to treat rock as an assembly of bonded particles that follow the law of motion and consider the model behavior dominated by the formation and interaction of micro cracks developed within the particle-particle cement (bond). Unlike the continuum methods, PFC can deal with the natural process from micro cracking to macro failure, without predefining a failure criterion for the rock. However, there are still issues related to the application of PFC to analyze different rock problems. For example, so far, most of the studies use PFC2D although many of the problems are three dimensional and should be better simulated with PFC3D. It is also found that the simulations using the default PFC parallel bond model extremely underestimate the ratio of unconfined compressive strength to tensile strength (UCS/T). So in the second part of the research, the important aspects related to the application of PFC3D, including model scale, particle size distribution and contact model, were studied, a new contact model was developed for addressing the limitation of the default PFC3D on obtaining unrealistically low UCS/T ratios, and finally the new contact model was used to investigate rock fracture initiation and propagation.

Anaerobic digestion, which is the process by which bacteria breakdown organic matter to produce biogas (renewable energy source) and digestate (biofertiliser) in the absence of oxygen, proves to be the ideal concept not only for sustainable energy provision but also for effective organic waste management. However, the production amount of biogas to keep up with the global demand is limited by the underperformance in the system implementing the AD process. This underperformance is due to the difficulty in obtaining and maintaining the optimal operating parameters/states for anaerobic bacteria to thrive with regards to attaining a specific critical population number, which results in maximising the biogas production. This problem continues to exist as a result of insufficient knowledge of the interactions between the operating parameters and bacterial community. In addition, the lack of sufficient knowledge of the composition of bacterial groups that varies with changes in the operating parameters such as temperature, substrate and retention time. Without sufficient knowledge of the overall impact of the physico-environmental operating parameters on anaerobic bacterial growth and composition, significant improvement of biogas production may be difficult to attain. In order to mitigate this problem, this study has presented a nonlinear multi-parameter system modelling of mesophilic AD. It utilised raw data sets generated from laboratory experimentation of the influence of four operating parameters, temperature, pH, mixing speed and pressure on biogas and methane production, signifying that this is a multiple input single output (MISO) system. Due to the nonlinear characteristics of the data, the nonlinear black-box modelling technique is applied. The modelling is performed in MATLAB through System Identification approach. Two nonlinear model structures, autoregressive with exogenous input (NARX) and Hammerstein-Wiener (NLHW) with different nonlinearity estimators and model orders are chosen by trial and error and utilised to estimate the models. The performance of the models is determined by comparing the simulated outputs of the estimated models and the output in the validation data. The approach is used to validate the estimated models by checking how well the simulated output of the models fits the measured output. The best models for biogas and methane production are chosen by comparing the outputs of the best NARX and NLHW models (each for biogas and methane production), and the validation data, as well as utilising the Akaike information criterion to measure the quality of each model relative to each of the other models. The NLHW models mhw2 and mhws2 are chosen for biogas and methane production, respectively. The identified NLHW models mhw2 and mhws2 represent the behaviour of the production of biogas and methane, respectively, from mesophilic AD. Among all the candidate models studied, the nonlinear models provide a superior reproduction of the experimental data over the whole analysed period. Furthermore, the models constructed in this study cannot be used for scale-up purpose because they are not able to satisfy the rules and criteria for applying dimensional analysis to scale-up.

13 | P a g e SUMMARY In South Africa’s rapidly changing social and cultural context, where family dynamics and relationships are changing just as quickly, it is essential to discover which factors contribute to successful relationships that persist over time. Previous research has utilised the Investment Model Scale (Rusbult, 1980) in order to understand commitment processes and the constructs satisfaction, quality of alternatives and investment have been identified as key determinants of commitment in romantic contexts. In the present study however I investigated the primary research question, “How can commitment be measured in the context of family relationships?” Data collection took place through the Family Commitment Scale (which was adapted from the Investment Model Scale) and a new meaningfulness scale was added in an attempt to explore whether meaningfulness would be a better predictor of family commitment than satisfaction, quality of alternatives and investment. The statistical analyses were conducted with the purpose of examining the research question and hypotheses. The findings of the present study contribute to commitment literature by underlining the utility of the Invest Model Scale in nonromantic contexts and providing an instrument which can reliably measure family commitment. Meaningfulness is also highlighted as a motivational feature behind family commitment processes. / Dissertation (MEd)--University of Pretoria, 2013. / gm2014 / Educational Psychology / unrestricted

<p>Workplace bullying is a major global issue which has received a lot of recognition because of its negative effects on victims’ health and work productivity. There have been many attempts to mitigate the effects of workplace bullying, leading researchers to extensively study the phenomenon in various contexts and relationships. Information on workplace bullying in the academic context, precisely relationships between academic advisors and graduate student advisees, is however, lacking. This study aimed at filling in the gap by seeking information about communicative behaviors from advisors that graduate advisees characterized as bullying, and common responses graduate advisees resorted to in the face of adversity. We also sought to understand why advisees may have responded to maltreatment in specific ways. We, therefore, proposed a working model which hypothesized a relationship between advisor negative acts, commitment levels of advisees, and advisee responses. Using Amazon’s Mechanical (MTurk) to recruit our sample, participants filled out a survey which included a few demographic questions, the revised version of the Negative Acts Questionnaire (NAQ-R) to measure advisor negative acts, the Exit-Voice-Loyalty-Neglect (EVLN) typology to measure advisee responses, and the Investment Model Scale (IMS) to measure advisee commitment levels to the work relationship with advisors. We verified the reliability and validity of the scales adopted for this study and ran some correlation and mediation analyses to answer our research questions and test our hypotheses. From our findings, we learned that most advisees reported personal insults occurring more frequently in their work relationships with advisors. Advisees also reported a high commitment to the work relationships with their advisors, despite maltreatment, and often responded by adopting the voice or neglect strategy. Findings from this exploratory study imply there is more information to be sought on workplace bullying between advisees and advisors in academic contexts.</p> <br> <p> </p>