The effect of the availability of student credit on tuition: testing the Bennett hypothesis using evidence from a large-scale student loan program in Brazil

Exploring the expansion of FIES—a large student lending program in Brazil— we test whether eligibility for subsidized student lending causes tuition to rise, in accordance with the Bennett hypothesis. FIES rules created arguably exogenous variation in eligibility across different majors and higher education institutions, which we exploit in a difference-indifferences framework. Using unique information on tuition, we document that FIES eligibility caused tuition to rise. We then estimate a structural demand model to explore whether a reduction in the sensitivity of demand to price increases is one of the possible mechanisms behind this credit-driven tuition rise. Our results show that FIES expansion is associated with a reduction in the tuition elasticity of demand

Automated information systems generation for process-oriented organizations

Currently, the development of organizational information systems remains a complex task. Final software product quality often does not match expectations. The existence of organizational models is the first step to reduce complexity in the development of information systems. Within the life cycle of an information system, activities are still very dependent in quality, time, and costs on the human resource skills that staff them. The existence of automated mechanisms to transform client requirements into characteristics of running systems would bring added value to the resulting software product, either in product quality and time perspectives. In this proposal, the manipulation of requirements must be done using an understandable model for both software engineers and business process experts. This model should be used to automatically reshape the running organizational information system and be the basis for an automated information system generation. The usage of such mechanism can be done during a development project, but also after its implementation where standalone process experts could change the organization model, knowing that the changes, in an automated mode, would be transferred into the running system

Business modeling in process-oriented organizations for RUP-based software development

Several organizations are nowadays not particularly comfortable with their internal structuring based on a hierarchical arrangement (sub-divided in departments), where collaborators with a limited view of the overall organization perform their activities. Those organizations recognize the need to move to a model where multi-skilled teams run horizontal business processes that cross the organization, and impact suppliers and clients. To develop software systems for any organization, the development process must always be appropriate and controlled. Additionally for organizations who want to migrate to a horizontal business processes view, it is required to model the organizational platform where the organizational processes will run. This necessity is also true when the organization under consideration is a software house. In this chapter, a proposal of a generic framework for process-oriented software houses is presented. The way of managing the process model and the instantiation of their processes with the Rational Unified Process (RUP) disciplines, whenever they are available, or with other kind of processes is recommended as a way to control and define the software development process. To illustrate the usefulness of the proposal, it is presented how the generic reference framework was executed in a real project called “Premium Wage” and shown, in some detail, the created artifacts (which include several UML models) during the development phases following the RUP disciplines, especially the artifacts produced for business modeling.(undefined

Comprehensive analysis and comparison of digital current control techniques for active rectifiers

This paper presents a comprehensive analysis and comparison of digital current control techniques for active rectifiers. These rectifiers are connect-ed to the power grid and are controlled aiming to obtain sinusoidal grid currents and unitary power factor. In this context this paper presents the principle of operation of a full-bridge full-controlled active rectifier, which is controlled by different digital current control techniques, namely, proportional-integral (PI) in stationary frame, PI in synchronous frame, PI sinewave (PIS), feedforward, sliding mode, and predictive. These digital current control techniques are explained in detail and is established a comparison in terms of their current errors in steady-state, as well as in terms of their digital implementation using the digital signal processor (DSP) TMS320F28335 from Texas Instruments.FCTCOMPETE: POCI-01-0145-FEDER-00704

Assessment and comparison of the Marennes-Oléron Bay (France) and Carlingford Lough (Ireland) carrying capacity with ecosystem models

Based on the individual growth, food limitation, population renewal through seeding, and individual marketable size, a theoretical model of the cultured species population dynamics was used to assess the carrying capacity of an ecosystem. It gave a domeshape curve relating the annual production and the standing stock under the assumption of individual growth limited by the available food in an ecosystem. It also showed the influence of mortality rate and marketable size on this curve and was introduced as a means to explore the global properties resulting from the interactions between the ecophysiology of the reared species and the environment at the ecosystem level. In a second step, an ecosystem model was built to assess the carrying capacity of MarennesOl ´eron bay, the most important shellfish culture site in France, with a standing stock of Crassostrea gigas around 100 000 tonnes fresh weight (FW) and an annual production of 30 000 tonnes FW. The ecosystem model focused on the oyster growth rate and considered the interaction between food availability, residence time of the water, oyster ecophysiology and number of individuals. It included a spatial discretization of the bay (box design) based on a hydrodynamicmodel, and the nitrogen or carbon cycling between phytoplankton, cultured oysters, and detritus. From simulations of the oyster growth with different seeding values, a curve relating the total annual production and the standing stock was obtained. This curve exhibited a dome shape with a maximum production corresponding to an optimum standing stock. The model predicted amaximum annual production of 45 000 tonnes FWfor a standing stock around 115 000 tonnes FW. The prediction confirmed some results obtained empirically in the case of MarennesOl ´eron bay and the results of the theoretical model. Results were compared with those obtained in Carlingford Lough (Ireland) using a similar ecosystem model. Carlingford Lough is a small intertidal bay where the same species is cultured at a reduced scale, with current biomass less than 500 tonnes FW. The model showed that the standing stock can be increased from 200 tonnes FW to approximately 1500 tonnes FW before any decrease of the production

Analysis of the deep chlorophyll maximum across the Azores Front

Physical, chemical and biological observations made in late July and August 1997 across the Azores Front (37ºN, 32ºW to 32ºN, 29ºW) are presented. The objectives of the study were: (1) to analyse horizontal and vertical profiles of temperature, salinity, density, nutrients and chlorophyll-a (Chl a) of the top 350 m; (2) to identify the main differences in the deep Chl a Maximum (DCM) and hydrographic structure between the water masses that pass north and south of the Azores Front; and (3) to estimate phytoplankton primary production in these water masses. Horizontal and vertical profiles of salinity, temperature, density, nutrients and phytoplankton pigments in the top 350 m were analysed. The Front separates two distinct water types: the 18 ºC ModeWater (18MW) of subtropical origin, and the 15 ºC ModeWater (15MW) of sub-polar origin. Differences in the DCM and hydrographic structure between 18 MW and 15 MW were observed in the contour plots of each section. The average Chl a concentration between 5 and 200 m depth decreased significantly from 15 MW to 18 MW. The same pattern was observed for the Chl a concentration at the DCM depth. A vertical one-dimensional model was used to estimate the phytoplankton primary production in the 15 MW and 18 MW and led to an estimated water column average gross primary productivity (GPP) between 1.08 and 2.71 mg C

Breve caracterização da flora da Ilha Graciosa

XI Expedição Científica do Departamento de Biologia - Graciosa 2004.Uma breve caracterização da flora vascular espontânea da ilha Graciosa é feita a partir da análise do seu catálogo de plantas vasculares (Pereira et al. 2004). A flora vascular Graciosense compreende no momento 437 espécies, 283 géneros e 98 famílias. O número de espécies introduzidas representa 67,3% do total de espécies presentes, enquanto a percentagem de espécies nativas se cifra apenas pelos 22,2%. A distribuição das espécies nos grandes grupos taxonómicos (Pteridophyta, Gymnospermae, Dicotyledoneae e Monocotyledoneae) difere com significado estatístico entre as espécies nativas e introduzidas. A contribuição das espécies introduzidas é maior a nível das dicotiledóneas e menor a nível dos pteridófitos quando comparada com a distribuição das espécies nativas.ABSTRACT: A short characterization of the spontaneous vascular flora of Graciosa Island is made from the analysis of it’s checklist of vascular plants (Pereira et al. 2004). At the moment 437 species, 283 genus and 98 families are recorded. The number of introduced species represents 67.3% of the total species while the native species correspond only to 22,2 % of the vascular flora. The species distribution on the main taxonomic groups (Pteridophyta, Gymnospermae, Dicotyledoneae e Monocotyledoneae) is significantly different between native and introduced species. The contribution of introduced species is superior in the Dicotyledoneae and inferior in the Pteridophyta when compared with the native species

Aluminum containing dendrimeric silica nanoparticles as promising metallocene catalyst supports for ethylene polymerization

Several aluminum containing dendrimeric silica nanospheres, DSAl materials, were prepared using different synthesis and post-synthetic procedures. These materials were used for the immobilization of Cp2ZrCl2 via direct impregnation. The support materials were rigorously characterized by TEM, N2 adsorption, FTIR (using pyridine as probe molecule) and SS-NMR to assess their morphological, textural and surface acidic properties. Supported catalysts were tested in ethylene homopolymerization using methylaluminoxane (MAO) as co-catalyst and scavenger. The relationships between the types and strength of acid sites, as well as the textural and morphological parameters of DSAl materials with the behavior of catalytic systems are explored in this work. The results analyzed in this paper confirm the importance that support surface acidity plays in the formation of the active species for ethylene polymerization and in its activity without neglecting the contribution of support textural properties as well.info:eu-repo/semantics/publishedVersio