Integration of Colombian refugees in Costa Rica : an ethnographic approach to the refugees' legal, economic, and social experiences

This qualitative study, based on interviews to 17 refugee families, attempts to identify the reasons behind the lack of integration of Colombian refugees in Costa Rica. The model of Immigrant Modes of Incorporation and the studies of Alejandro Portes and Julia Sensenbrenner about the sources of social capital on migrant communities provided the theoretical framework used to identify the roots of the integration challenges. The findings suggest that Costa Rican policies towards the reception and integration of Colombian refugees are exclusionary. The host labor market is marked by sentiments of xenophobia towards the sample population while reported cases of persecution in the country also inhibit this population's economic integration. The lack of social capital sources contributes to inhibit this community's development, despite their participation in informal networks. There were signs of collective action. Yet, the refugee community fails to come together, while it also seems alienated from the community of Colombian entrepreneurs in Costa Rica.

An Institutional, Socio-economic, and Legal Analysis of Fisheries Co-management and Regulation in the Gulf of Nicoya, Costa Rica

Marine Areas for Responsible Artisanal Fishing (AMPR) have emerged as a new model for co-managing small-scale fisheries in Costa Rica, one that involves collaboration between fishers, government agencies and NGOs. This thesis aims to examine the context for collective action and co-management by small-scale fishers; evaluate the design, implementation, and enforcement of AMPRs; and conduct a linguistic analysis of fisheries legislation. The present work relies on the analysis of several types of qualitative data, including interviews with 23 key informants, rapid rural assessments, and legal documents. Findings demonstrate the strong influence of economic factors for sustaining collective action, as well as the importance of certain types of external organizations for community development and co-management. Additionally, significant enforcement gaps and institutional deficiencies were identified in the work of regulating agencies. Legal analysis suggests that mechanisms for government accountability are unavailable and that legal discourse reflects some of the most salient problems in management.

A Model for Continuous Measurement of Drilled Shaft Diameter During Construction

Non-Destructive Testing (NDT) of deep foundations has become an integral part of the industry’s standard manufacturing processes. It is not unusual for the evaluation of the integrity of the concrete to include the measurement of ultrasonic wave speeds. Numerous methods have been proposed that use the propagation speed of ultrasonic waves to check the integrity of concrete for drilled shaft foundations. All such methods evaluate the integrity of the concrete inside the cage and between the access tubes. The integrity of the concrete outside the cage remains to be considered to determine the location of the border between the concrete and the soil in order to obtain the diameter of the drilled shaft. It is also economic to devise a methodology to obtain the diameter of the drilled shaft using the Cross-Hole Sonic Logging system (CSL). Performing such a methodology using the CSL and following the CSL tests is performed and used to check the integrity of the inside concrete, thus allowing the determination of the drilled shaft diameter without having to set up another NDT device. This proposed new method is based on the installation of galvanized tubes outside the shaft across from each inside tube, and performing the CSL test between the inside and outside tubes. From the performed experimental work a model is developed to evaluate the relationship between the thickness of concrete and the ultrasonic wave properties using signal processing. The experimental results show that there is a direct correlation between concrete thicknesses outside the cage and maximum amplitude of the received signal obtained from frequency domain data. This study demonstrates how this new method to measuring the diameter of drilled shafts during construction using a NDT method overcomes the limitations of currently-used methods. In the other part of study, a new method is proposed to visualize and quantify the extent and location of the defects. It is based on a color change in the frequency amplitude of the signal recorded by the receiver probe in the location of defects and it is called Frequency Tomography Analysis (FTA). Time-domain data is transferred to frequency-domain data of the signals propagated between tubes using Fast Fourier Transform (FFT). Then, distribution of the FTA will be evaluated. This method is employed after CSL has determined the high probability of an anomaly in a given area and is applied to improve location accuracy and to further characterize the feature. The technique has a very good resolution and clarifies the exact depth location of any void or defect through the length of the drilled shaft for the voids inside the cage. The last part of study also evaluates the effect of voids inside and outside the reinforcement cage and corrosion in the longitudinal bars on the strength and axial load capacity of drilled shafts. The objective is to quantify the extent of loss in axial strength and stiffness of drilled shafts due to presence of different types of symmetric voids and corrosion throughout their lengths.