This paper is based on the interest of knowing more about cooperative learning and the possible impact it has on primary students' education. Using cooperative learning as a method in school is mostly to involve the students more in their learning process. Through discussions and other structures students have a chance to express themselves and every student can participate in the activity. Our purpose for doing this study is to bring forward the positive aspects of using cooperative learning but also the challenges. Our research questions are: 1. How is cooperative learning used? 2. How do teachers describe cooperative learning and the contribution to students´ language development? Our paper is based on the sociocultural theory which cooperative learning has evolved from. It is important for pupils to use talking skills in school. The methods we used to collect data was through interviews and observations. We interviewed six different active teachers and observed four of them. The material we used to record the interview was a dictaphone. One of us asked the questions and the other made notes by writing down some keywords in case there was something wrong with the recording. The results show us cooperative learning may make the classroom environment a bit noisy. However, this still works since the method has more benefits than challenges. In conclusion, the interviews and the observations reveal the result of how cooperative learning contributes to students' learning by benefiting the students.

The main goal of our thesis is to understand qualitative properties of solutions to the Cauchy problem for the semi-linear wave model with time-dependent speed and dissipation. We greatly benefited from very precise estimates for the corresponding linear problem in order to obtain the global existence (in time) of small data solutions. This reason motivated us to introduce very carefully a complete description for classification of our models: scattering, non-effective, effective, over-damping. We have considered those separately.

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La degradación del bosque tropical causada por la agricultura indigena tradicional y la explotación forestal comercial fue evaluada, en el sector central de la Reserva Forestal Imataca en la Guayana venezolana.El enfoque conceptual de paisajes permitió combinar dos niveles de análisis, local y paisajes, con el objeto de detectar las relaciones espaciales que forman patrones, gradientes y estructuras, útiles para el seguimiento y control de los usos del bosque tropical y su estado de conservación. La evaluación integró varios métodos orientados a describir y analizar la composición, estructura y distribución de las comunidades arbóreas, tomando en cuenta su condición: no perturbado o perturbado.Se levantó información social relativa a los usos de la tierra considerados, a través de visitas y mediciones en las áreas de producción de las comunidades Kariñas, al igual que en concesiones forestales tomadas como muestra. Un inventario forestal en parcelas muestra, permitió colectar datos sobre algunos parámetros estructurales del bosque, los cuales sirvieron de base para calcular índices tales como diversidad alfa y beta, complejidad estructural y otros. La detección y cartografía de los bosques no perturbados y perturbados segun el uso considerado, se hizo sobre imagenes de satélite Landsat, a las cuales se aplicó técnicas de percepción remota tales como analisis textural, indices de vegetación y cobertura fraccional.Se estimaron áreas de superposición entre territorios tradicionales Kariña y concesiones forestales comerciales, las cuales probablemente serán objeto de nuevos conflictos que pueden ser graves, considerando el proceso de demarcación de territorios indígenas tradicionales en curso, y la explotación minera próxima a comenzar.El interés de estudiar la compleja situación de la Reserva Forestal Imataca se debe a la necesidad de promover un modelo sustentable de manejo y conservación de bosques para la Guayana venezolana.

The main goal of our thesis is to understand qualitative properties of solutions to the Cauchy problem for the semi-linear wave model with time-dependent speed and dissipation. We greatly benefited from very precise estimates for the corresponding linear problem in order to obtain the global existence (in time) of small data solutions. This reason motivated us to introduce very carefully a complete description for classification of our models: scattering, non-effective, effective, over-damping. We have considered those separately.

No description available.