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Modelos de programação matemática para problemas de carregamento de caixas dentro de contêineres
(Universidade Federal de São Carlos, 2009-02-26) Junqueira, Leonardo; Morabito Neto, Reinaldo; https://lattes.cnpq.br/2179657609596194
The object of this study is a particular case of the cutting and packing problems, known as container loading problems. These problems consist in arranging rectangular boxes orthogonally into containers (or into trucks, railcars and pallets), in order to optimize an objective function, for example, maximize the utilization of the available space, or minimize the number of the required containers to load all the available items. The objective of this study is to develop mathematical programming models to deal with situations commonly found in container loading practice. Multiple orientations of the boxes, weight limit of the container, cargo stability, load bearing strength of the boxes and multiple destinations of the cargo are considered. The author is not aware of mathematical formulations available in the cutting and packing literature that deal with such considerations, and this paper intends to contribute with possible formulations that describe these situations, although not very realistic for being used in practice. Computational experiments with the proposed models are performed with the software AMS/CPLEX and randomly generated instances extracted from the cutting and packing literature. The results show that the models are consistent and properly represent the practical situations treated, although this approach (in its current version) is limited to solve to optimality only medium-sized problems. However, we believe that the proposed models can be useful to motivate future research exploring decomposition methods, relaxations, heuristics, among others, to solve the present problems.
Economia solidária e aprendizagem dialógica : práticas de participação e autogestão e necessidade de uma outra EJA
(Universidade Federal de São Carlos, 2009-02-26) Pereira, Kelci Anne; Logarezzi, Amadeu José Montagnini; https://lattes.cnpq.br/6153358744019882; https://lattes.cnpq.br/2206007189343788
In this research we seek to investigate the development practice done by Unesp Development Center among settled people of Grupo Viverde de Agroecologia in order to form a community venture (EES). The development process has been done since January 2008, at Terra Nossa Settlement, located between the cities of Bauru and Pederneiras, state of Sao Paulo. It is connected to the Domestic Farming Federation (FAF) which was founded to promote a better life to its participants and to generate earnings through work done in the settled land. In the present time it involves twelve families from the settlement, those who produce food in agroecological transition in their lots. The families have weekly meetings to sell the products in baskets and to determine ways of development by acquiring different habilities and skills to set a community venture. In this context the research segmented two main concepts. The first concept is the mutual economy, for embracing the extended development as an educative and political process, for configuring itself as a wide range of work practices based on solidariety and on the self management; also by having the purpose of ensuring an amplified reproduction of life by overcoming the capitalist relations. The second concept is the dialogical learing, for allowing a deeper insight of the development process as it establishes itself in the center of the theories of Freire s dialogicity and Habermas communicative action, conceiving that everyone can dialog and communicate, educating themselves in the interactions in order to accept themselves as subjects and producing personal changes thus overcoming social differences. Hence, the dialogical learning gives evidences to cultural intelligence which is important to the fair dialog that connects to the instrumental dimension and then promoting solidariety, creating sense and the struggle for social equality regarding the social differences. Consistently with the theoretical focus, the chosen research methodology is the critical-communicative whose strictness is reached by the intersubjective dialog between researcher and subjects, among intertwined theoretical understandings with those risen from life. The required dialogic and shifting posture claims that the subjects take part from the point of defining the research queries to the data analysis. As a result, along with the four subjects from the Grupo Viverde who worked with us during the research (two women and two men), we determined to answer the question which factors are obstacles and which ones are shifting factors in order to start up an agro-ecological community venture from the development process focusing the self management and group participation? . The dialogically reached results gave evidence that there are many shifting factors in the developing process such as the overestimation of cultural intelligence, the gain of self esteem for settled people and the agro-ecology expansion in the settlement. As a contrast, there were obstacles since some subjects focused more on capitalizing and the lack of expertise by others derived from the biased schooling model promoted by EJA, which is incompatible to adults intelligence and educational and professional needs. To think about overcoming this obstacle, we aspire an EJA based on the dialogical learning. This way, we intend to contribute to the educational insight in this development process and others as well.
Fracionamento de zinco em amostras de leite
(Universidade Federal de São Carlos, 2009-02-26) Bossu, Carla Maíra; Nogueira, Ana Rita de Araújo; https://lattes.cnpq.br/7034773971317045; https://lattes.cnpq.br/2789193033004313
This work studies were aimed at samples preparation and chemical speciation levels zinc in samples of different kind of milk (milk cattle, sheep, goat, and soybean milk base). The proposal aimed to establish the differences in the zinc levels in protein samples, trying to observe the distribution and zinc bioavailability due to treatments such as pasteurization. The samples were digested in a cavity microwave oven and the total Zn, Ca and P levels in extracts were determined by inductively coupled plasma optical emission spectrometry (ICP OES). An additional study was conducted for protein samples separation in different kinds of milk using the urea polyacrylamide gel electrophoresis (UREA-PAGE) methodology and posterior determination of Zn bound to protein bands. Therefore the protein bands were digested in the cavity microwave oven and the Zn levels were determined by graphite furnace atomic absorption spectrometry (GFAAS). The results displayed that Zn is mainly bound to 32 kDa (β-casein) protein in UHT whole milk and to the 24 kDa (α-casein) protein in raw sheep milk. There were not major differences between the Zn-proteins binding at the pasteurization process. After optimization experimental conditions, in vitro simulated gastric digestion was applied to Zn, Ca and P bioaccessibility in the studied samples. The results confirmed the adopted methodology efficiency. Furthermore, the pasteurization process did not affect the total proteins concentration of bovine milk.
Pesquisa-ação sobre as formas de promover um aumento na participação dos funcionários no desenvolvimento e uso do sistema de medição de desempenho de uma empresa de bens de capital
(Universidade Federal de São Carlos, 2009-02-26) Leal, João Batista Sobreira; Martins, Roberto Antonio; https://lattes.cnpq.br/3518820028045730
The purpose of this essay is to investigate ways to promote an increase at the participation of employees in the development and use of the performance measurement system in an industrial goods manufacturer. Along with economical globalization, several performance measurement models begin to appear and companies in general are brought to invest in the search for the model that better fits each one s purpose. The effort is focused in the development, implementation and use of performance measurement systems. Among a number of proposed models, the one that gained more recognition worldwide was BSC. This fact itself does not guarantee the full use of the performance measurement system. Employee s participation and commitment has been an issue that deserves attention from researchers because it is an unquestionable fact that its involvement increases the performance of the individual and improves the motivation of the group. For this research it was chosen the action-research method, due to the fact of it to allow researchers to play an active role in the very reality of observed facts. The research had the support of large bibliographic studies to identify and evaluate influent factors to development and evolution of SMD. During action-research work, questionnaires were applied, interviews were conducted and thoughts were made about the adopted actions and results achieved. As a final result of field research, a better understanding of process change, skill development in the use of SMD, system management and involvement of stakeholders were achieved. Recommendations resultant of this research included managers, quality management staff and executives of the company, the development of employees, the improvement of SMD use, ownership and continuous improvement of the business.
Modelos de séries temporais com coeficientes variando no tempo
(Universidade Federal de São Carlos, 2009-02-26) Souza, Leandro Teixeira Lopes de; Moura, Maria Sílvia de Assis; https://lattes.cnpq.br/9410151859448447; https://lattes.cnpq.br/9758799382568880
In this work they are presented extensions of Auto Regressive and Auto Regressive Conditional Heteroscedasticity models with coefficients varying in time. These coefficients have been used as models for non stationary real time series, specially for financial series. The objective of this work is to present the models and the techniques involved in estimating time-varying coefficients, moreover, it is made an introduction to financial modeling and some suggestions in order to facilitate implementation and use of models with time-varying coefficients. The simulation studies and the application on real data showed that the models have great potential to be exploited in the analysis of non-stationary series. The suggestions in confidence band and forecasting for the Auto regressive models with time-varying coefficients enable the use of models in financial data and other series that show a non-stationary characteristic. The modified algorithm for estimation of ARCH models varying in time was to increase the rate of convergence. The creation of a method for forecasting for ARCH models require a deeper study, although the algorithm has shown promising results in simulation study, giving some evidences that it can be applied in real situation. Finally, the contributions in the creation of functions for a free software that facilitate the use and the analysis of the models studied and the use of the proposed methods.
A qualidade do relacionamento conjugal e o desempenho social de crianças pequenas
(Universidade Federal de São Carlos, 2009-02-26) Machado, Fabiana Rocha; Barham, Elizabeth Joan; https://lattes.cnpq.br/9868595523538592; https://lattes.cnpq.br/5238757469332055
The scientific literature indicates that certain family characteristics can act as risk factors for children s social development, such as low income and low educational attainment levels, adolescent pregnancy, social isolation, parents who are highly stressed, single-parent families, a parent with a psychiatric disorder (including depression), parents with a criminal history, a history of drug abuse, or a high-conflict spousal relationship. More detailed information about some of these factors is lacking, particularly with respect to the Brazilian context, as in the case of spousal conflicts. Such information is essential to permit the construction of preventive programs that could reduce risk factors for infant social development, in Brazil. Risk factors can contribute to the development of problem behaviors among children and, as a result, interfere in their social relationships, as well as contributing to other difficulties such as learning problems, depression, anxiety and other psychological conditions. For this reason, the identification and prevention of risk factors that can harm human development is one of the research areas of the Special Education Graduate Program at the Federal University of São Carlos (Brazil). Although the number of Special Education prevention programs has increased significantly, especially in the United States, there are few prevention programs in this area, in Brazil, resulting in a situation in which professionals face the difficult task of remediating long-term problems. Considering the paucity of Brazilian studies that aim to verify the impacts of conflicts in the spousal relationship on infant social development, particularly among very young infants, the objective of this study was to investigate the relationships between personal parent-characteristics, characteristics of the spousal relationship and the social performance of their child, between one and two years of age. Given the exploratory nature of this study, a non-experimental design was used. Participants included 27 couples and their target child, who was between 15 and 26 months of age and who attended a daycare center in the city of Araraquara, São Paulo, Brazil. The parents completed an instrument to evaluate their socioeconomic situation, a Marital Social Skills Inventory, a Description of Conflict Situations, and Lipp s Adult Stress Symptoms Inventory. The Operationalized Portage Inventory was used to evaluate the children s social performance. Although there was a certain amount of variability in the participants responses, the correlations between the parents personal characteristics and their child s social performance were non-significant. With respect to the parents marital social skills, in this sample, there was a significant negative correlation between the frequency with which the parents reported that they stomped out of the room, and the child s social performance (r = - 0.48, p < 0.05). Using the results from this study together with those from other studies about this topic, it should be possible to create programs that can help prevent problems in families with children in this age group, striving to provide them with the means to transform some of the characteristics of their spousal relationship so that they will be protective factors for their child s development.
Simulações por dinâmica molecular de compostos do tipo ABO3 (SrTiO3 e CaTiO3)
(Universidade Federal de São Carlos, 2009-02-26) Souza, James Alves de; Rino, José Pedro; https://lattes.cnpq.br/6801067322823031; https://lattes.cnpq.br/2212240621620011
Using the classical molecular dynamics simulations, Perovskites systems composed by oxides (ABO3), in particular SrTiO3 and CaTiO3, were performed. The titanates are easily prepared as polycrystalline ceramics; chemically and mechanically stable they can be characterized in various temperature and pressure conditions. These provide us reliable experimental results for construction and consolidation of theoretical models. Another important fact is that these materials have wide variety of technological applications and many important properties as well as the phase transitions arising from the effect of temperature and pressure. That can be explored to understand the interactions among its constituents. The effective interatomic potential used has the same functional form of the potential proposed by Vashishta and Rahman and it s composed by the sum of terms Coulomb interaction, van der Waals, esthereometric and dipole-induced. The system was treated in (N, V, E) and (N, P, H) ensembles to verify the influence of temperature and pressure application on structural and dynamics properties of perovskites. The method used allowed us to describe various properties such as thermal expansion coefficient, angles distribution, coordination number, elastic properties, pair distribution function, density of vibrational states, Debye-Waller factor and so on. The phase transitions of systems were explored showing fantastic results.
Análise dos direcionadores de competitividade para a cadeia produtiva de biodiesel: o caso da mamona
(Universidade Federal de São Carlos, 2009-02-26) César, Aldara da Silva; Batalha, Mario Otávio; https://lattes.cnpq.br/1015001063418091; https://lattes.cnpq.br/7269278746075136
Biodiesel has been receiving great attention in Brazil. A federal program called National Program for Production and Use of Biodiesel (PNPB) and its corresponding legislation have created a huge demand for biodiesel. Furthermore, the PNPB began to stimulate not only its production from various types of oil but also its social inclusion. For this reason, this federal program established a set of policies aiming to include family farmers in the biodiesel production process in a sustainable way. Despite the real and potential growth of the Brazilian biodiesel market, it is surrounded by many uncertainties, especially with regard to its sustainability and economic viability in long term. The PNPB is strongly based on social development through the inclusion of family farmers in projects integrated with biodiesel plants. Among the various oilseeds, castor bean was identified as the ideal one to promote social development in the northeast. However, although promising, the mechanisms of the federal program are still insufficient to promote effective participation of family farmers, which are in the margin of this segment. The castor oil is considered a noble product. It is more expensive than many types of oil in the international market, which makes its use as fuel impracticable. Moreover, it is difficult to make the castor biodiesel technology follow the standards required by the National Petrol Agency. Considering these aspects, there has been some tendency of biodiesel plants - which continue to foster productive systems with castor oil to act as an intermediary in the ricino oil productive chain. Many efforts have been directed to enhance the agreements between producers and biodiesel plants. However, research shows that companies are facing huge problems in implementing contracts with family farmers. This dissertation intends to advance in the identification and the discussion of these obstacles, in order to increase the competitiveness of the biodiesel agribusiness chain, based on castor oil projects in Brazil. This dissertation describes and analyzes the functioning dynamics of this agroproduction chain, identifying the stakeholders who participate directly and indirectly of this chain. A competitiveness analysis model is proposed for the biodiesel production chain, and it is used to assess the competitiveness of agribusiness chain, mainly considering the bonds between industrial and agricultural production.