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Otimização da configuração e operação de sistemas médicos emergenciais em rodovias utilizando o modelo hipercubo.
(Universidade Federal de São Carlos, 2005-03-11) Iannoni, Ana Paula; Morabito Neto, Reinaldo
The purpose of this study is to develop effective methods to analyze the configuration and operation of the emergency medical systems (EMS) on highways. Due to the stochastic nature of these systems, especially in the arrival and assistance processes of the emergency calls, we apply the Hypercube Queuing Model to evaluate the performance measures of the system. This is a well-known model in the location literature, which is based on spatially distributed queuing theory. The EMS on highways operate within a particular dispatching policy which considers that only some ambulances in the system can travel to certain regions (partial backup) and multiple dispatch of ambulances to respond to certain calls. In this study we extend the Hypercube model to deal with these situations. Since the Hypercube model is a descriptive model, we also develop a Hypercube embedded genetic algorithm to create a prescriptive approach to optimize the configuration and operation of EMS on highways. This approach can support decisions at the strategic level, for example, the location of ambulances along the highway and the primary response area to each ambulance, as well as, decisions on the operational level, for example, the optimal dispatch policy of ambulances to respond to the emergency calls and the coverage area to each ambulance (if the system configuration can be modified according to the operational conditions of the week or the day). In order to evaluate the performance of the proposed approach, we conducted experiments using the data of two realsystems: the EMS Anjos do Asfalto (Presidente Dutra highway) and EMS Centrovias (portions of the highways Washington Luis, Eng. Paulo Nilo Romano e Comandante João Ribeiro de Barros) in São Paulo State. The results show that the approach is effective to support planning and operation decisions in such systems.
Aspectos ecológicos e sociais da coleta informal de resíduos sólidos urbanos do município de São Carlos - SP
(Universidade Federal de São Carlos, 2005-03-11) Rancura, Sheila Aparecida de Oliveira; Nordi, Nivaldo; https://lattes.cnpq.br/8168865557947289
This work was developed along with informal waste collectors of recyclable solid waste in the urban area of the city of São Carlos SP. An effort has been performed with the aim of combining ecological studies with the garbage problematic and social exclusion the informal waste collection brings. The adequacy of concepts of the ecological theory (ecological niche, foraging models) to the case of the waste collectors studied allowed placing the role of individuals in the ecosystem and inferring on the resource utilization forms and their implications for the environment. The methodological procedures used combined direct observations and free interviews with structured questionnaires (socioeconomic and informal collection production data). Most informal waste collectors (80%) present generalist collection strategy, also presenting, however, high dependence degree on some types of waste such as aluminum, paper and ferrous materials. The behavior of the informal waste collectors is similar to behavior predicted for foragers by the optimal foraging theory. The contribution of the informal collection for recycling market is of order of 97.3 kg/day/collector, being hidden by its stealth situation and the gains they profit are found at minimum levels as possible in order to allow they subsistence. One of the effects of this activity on the environment is its performance as negative feedback on one component the garbage which causes environmental deterioration. One believes that the recognition of the collection social and environmental importance and its removal from informality are the first step to change the stealth situation that informal waste collectors are submitted to.
Uso do método do trabalho essencial de fratura (EWF) para avaliar a tenacidade de blendas poliméricas
(Universidade Federal de São Carlos, 2005-03-11) Yamakawa, Roberto Seiji; Hage Júnior, Elias; https://lattes.cnpq.br/1240692926327687
Initially it was made a well elaborated study on the essential work of fracture method (EWF) using the polyamide 6 (PA6) because this polymer shows high difficult to evaluate its toughness. The PA6 is a semi-crystalline polymer, so its mechanical properties are highly affects by the specimen processing conditions. This material is also highly susceptible to the notch, so it is necessary to study how the conditions to obtain the notch and pre-crack can affect the applicability of the EWF method. The best specimen dimension to work in plane stress condition was determined for the uniaxial tensile test. This first study allowed determining the best specimen condition to apply the EWF method. The EWF method was used to evaluate the toughness of polymeric blends. One of the blend was prepared with a semi-crystalline matrix (PA6/ABS) and other with amorphous matrix (PC/ABS). It was also studied the efficiency of the MMA-MA compatibilizer on the PA6/ABS blend toughness. The results allowed concluding that the EWF method was able to verify the improvement of toughness in the blends when compared with the pure polymers as well as the improvement of toughness when the compatibilizer is added to the blend. It was also studied the influence of specimen thickness, strain rate and injection molding conditions like injection speed and mold temperature on the parameters of EWF method. The results allowed concluding that all variables affected the specific essential work of fracture, we, while the specific nonessential work of fracture, βwp, was not affect by that variables, except in the highest test speed for PA6 and in the different thickness for the PA6 and PA6/ABS/MMA-MA blend.
Proposta metodológica para subsidiar a determinação do grau de impacto ambiental em empreendimentos minerários na região de Descalvado e Analândia
(Universidade Federal de São Carlos, 2005-03-11) Torresan, Fábio Enrique; Lorandi, Reinaldo; https://lattes.cnpq.br/7794241793056671
This paper has the main objective of proposing methodological procedures for the analysis of the environmental impact degree and respective compensation calculation, in accordance with the Article 36 of Law 9.985. The research was consolidated through a case study specifically applied for the analysis of mining enterprises, in the region of Descalvado an Analandia, Sao Paulo State, Brazil. Through the application of geoprocessing tools, environmental information were converted into environmental impact degree indicators, related mainlyto the intensification of erosive processes, biodiversity loss and impacts on the hydrological resources. The present methodological proposal represents an important instrument of environmental management for the assessment of conservation priorities and alternatives for location of enterprises. The results showed that the region of Descalvado and Analandia presents high environmental fragility, due to it's high potencial to cause erosion and also due to their fragments of natural vegetation. It was proposed the creation of an Protected Area.
Determinação da energia de fratura em materiais cerâmicos em altas temperaturas
(Universidade Federal de São Carlos, 2005-03-11) Santos, Sérgio Francisco dos; Rodrigues, José de Anchieta; https://lattes.cnpq.br/4000441989868775
In this work, the main objective was to determine the energy of fracture in ceramic materials, focused on refractories, at high temperatures and to inquire the interference of the creep on this measurement. Therefore, castable containing white fused and calcined aluminas, hydrated alumina as a binder, with and without, a glass of SiO2-CaO-Al2O3-B2O3-MgO was designed. This material can simulate the real situation of refractory castables that present possible glassy phase formation due to the presence of cement, silica fume and impurities of raw materials. In addition to this material two commercial refractories were also characterized. Physical characterizations, refractoriness under load, modulus of rupture, Young's modulus and coefficient of linear thermal expansion were evaluated. The energy of fracture was measured through stable crack propagation in three-point bending tests. The creep curves were obtained in three-point bending and compression tests. The concept of rate of energy of creep deformation was used to evaluate creep semiquantitatively as well as to consider a description for the energy of fracture at high temperatures. The results indicate that a maximum in the energy of fracture measured through stable crack propagation under three-point bending tests occurs as a function of temperature. For this case it will exist a range of temperature at which the material will suffer a transition from brittle to ductile behaviour due to the presence of glassy phase in the microstructure. In the transition, bridges of glassy phase contribute for the increase of the average energy for crack propagation. Consequently, these results have strong influence on the thermal shock damage resistance parameters.
Abordagem via integrais de trajetória do processo de troca e dissipação de energia num sistema composto por dois osciladores harmônicos dissipativos acoplados - o modelo duplicado de Caldeira & Leggett
(Universidade Federal de São Carlos, 2005-03-11) Cacheffo, Alexandre; Moussa, Miled Hassan Youssef; https://lattes.cnpq.br/7828776012924524; https://lattes.cnpq.br/1355079087830286
In this work, we analyse the dissipation and interchange of energy in a system composed by two harmonic oscillators, each one associated with a thermal reservoir. To this end, we employ the Caldeira & Leggett approach, based on path integral formulation, to obtain the time evolution of the reduced density operator of the system composed by both oscillators.
Análise das oportunidades de aprendizagem em aulas expositivo-participativas: estudo de caso de um professor de Biologia
(Universidade Federal de São Carlos, 2005-03-11) Camargo, Cristiane Cordeiro de; Mello, Maria Aparecida; https://lattes.cnpq.br/8338726751746542
This work is inserted in an investigative line, guided by a cognitive learning framework, seeking to understand how speech, in the teaching environment, has impact upon the learning process of students. Using as outline suggested questions from the teacher in participative lectures and the reactions to the students responses, this investigation aimed to answer two questions: a) How does the analysis of the interaction teacher-student in participative lectures enable the identification of possible learning opportunities? b) Which are the variables involved in the process that go from the intentions in teaching practice, to the opportunities of learning offered? To proceed in this analysis, we have sought reference in social-historical psychology authors regarding the caracterization of the thought process and the structure of scientific knowledge ( Petrovsky, 1980; Vygostky, 1993 ); authors who, using as a starting point social-historical psychology, have developed concepts and interpretations on the functions of speech in learning activities ( Scott, 1998; Mercer, 1996; Wegerif et al, 1999 ); authors who deal with forms of relationship in regard to knowledge, as they materialize in the teaching environment ( Edwards, 1997 ). This work is characterized as a descriptive-analytic study of a biology teacher; of qualitative nature, presented in case study format. The data was collected thru means of observation and registry of given lectures as well as an interview with the teacher. Results indicate that the identification of learning opportunities offered by the teacher, by means of interventions, can only be comprehended if articulated to the logics of context ( structure of scientific concepts ) and interaction ( structure of participation, that is, the implied rules that guide the students and teacher s participation in their speech during class). These opportunities sometimes don t correspond to the ones idealized /verbalized by the teacher, as they suffer influence of many variables in the process of materialization in class. Among these are the ones related to the basis of knowledge of the teacher in teaching skills, in terms of knowledge of a specific area as well as in the pedagogic area. A correct articulation between the two types of knowledge can enable a more adequate one between the teacher s interventions and the mental processes necessary to the elaboration of certain scientific knowledge by the students. Beyond that, results also show the utility of theoretical structures, deriving from concepts such as scafolding ( Bruner et al, 1976, apud Scott, 1998 ) for the analysis of concrete situations in teacher-student interaction during participative lectures.