A garantia de qualidade de serviço (QoS) tem-se demonstrado muito importante em aplicações em tempo real. Este trabalho apresenta um estudo sobre Mecanismos de Policiamento na tecnologia A TM, mais especificamente, sobre o funcionamento do Mecanismo Dual Leaky Bucket, utilizado pela classe de serviço VBR em rede ATM. Para este estudo foi implementado um simulador por software do mecanismo Dual Leaky Bucket. Foram analisados dois tipos de tráfegos de vídeo com compressão MPEG-2, com pouca e muita movimentação. A partir da simulação pôde-se analisar como o erro na definição de parâmetros do contrato de QoS definidos pelo usuário no estabelecimento da conexão pode levar ao aumento na taxa de perda de informações e, conseqüentemente, a degradação da qualidade necessária pela aplicação / The guarantee of quality of service (QoS) has been demonstrating very important in real time applications. This work presents a study on Policing Mechanisms in the ATM technology, more specifically, on the operation of the Dual Leaky Bucket Mechanism, used by the class of service VBR in ATM networks. For this study a Dual Leaky Bucket mechanism simulator by software was implemented. Two kinds of MPEG-2 video traffics were analyzed with a little and a lot of movement. The simulation shows how a mistake in the definition of parameters in the QoS contract, defined by user, during of the connection establishment can leads to increase of information loss rate and, consequently, the degradation of the necessary quality for the application

Em aproveitamentos hídricos, onde podem estar envolvidas elevadas alturas de água armazenada, o vertedouro é a estrutura hidráulica responsável por conduzir com segurança o escoamento que excede a capacidade de armazenamento do reservatório. Neste aspecto, é necessário considerar o processo de dissipação de energia a fim de proteger o pé da barragem e a própria estrutura do vertedouro contra a ação erosiva da água. Este fluxo que é descarregado é usualmente amortecido por um colchão d’água, o qual é delimitado em uma bacia de dissipação projetada com intuito de resistir aos esforços impostos pelo escoamento. Em grandes barramentos, a utilização de um vertedouro tipo salto esqui, que é caracterizado por um defletor de fluxo no final de sua calha, possibilita que não haja necessidade de revestir o leito próximo do pé da barragem, pois a incidência do jato lançado ocorre distante deste local. Desta maneira, a dissipação da energia é efetuada sobre o próprio leito do rio, sendo formada uma fossa de erosão, contudo, dependendo da resistência do leito e de suas características anisotrópicas, os padrões de recirculação do fluxo podem fazer a fossa evoluir para uma situação nociva. Por isso, desde a fase de projeto desse tipo de vertedouro, monitoramento e previsões da progressão da fossa são essenciais. Então, conforme proposta deste trabalho, abordou-se cada fenômeno que influencia no potencial erosivo do jato, como a turbulência em sua emissão e o grau de difusão do mesmo no colchão d’água. Assim, com ensaios sobre modelo físico, foi possível desenvolver duas metodologias, aplicáveis tanto para a verificação da erosão de material granular na superfície de leitos, quanto para o interior de leitos rochosos fissurados, cujas forças atuantes em um bloco de rocha isolado, podem vencer seu peso submerso e o destacar da matriz. / In hydroelectric plants, which may be involved elevated heights of stored water, the dam spillway is responsible for safely flow the water that exceeds the storage capacity of the reservoir. In this respect, it is necessary to consider the process of energy dissipation in order to protect the base of the dam and the spillway structure itself against the erosive action of the water. This stream discharged is usually cushioned by a waterbed, which is bounded into a stilling basin designed with the purpose of resist the efforts imposed by the flow. In large dams, the use of a ski jump spillway type, which is characterized by a flow deflector at the end of its chute, allows no need lining the bed near the foot of the dam, since the impact of the jet is launched away this location. Thus, the energy dissipation is performed on the riverbed itself, generating a scour hole, however, depending on the resistance of the bed and its anisotropic features, patterns of flow recirculation can evolve the pit into a harmful state. For this reason, since the design phase of this type of spillway, monitoring and predicting the progression of the pit are essential. Then, according to the proposal of this work, it was dealt with each phenomenon that influences the erosive potential of the jet, as the turbulence at its issue on the air, and the level of its diffusion of on waterbed. Based on physical model tests, it was possible to develop two methodologies, applicable both for verifying erosion of granular material from the surface of the bottom, as for analyze the interior of a fissured bedrock, which the forces acting on an isolated block of rock can overcome its submerged weight and uplift it off the matrix.

[pt] A programação de máquinas é um processo de tomada de decisão que desempenha um importante papel na maioria das indústrias de manufatura e serviços. Esta dissertação aborda o problema de programação de máquinas paralelas idênticas sem preempção, considerando características da programação de data de liberação e data limite para execução do início das tarefas, restrição de precedência entre pares de tarefas, elegibilidade e disponibilidade de máquinas. Para resolver este problema, uma formulação de programação linear inteira mista é proposta. O novo modelo, chamado de bucket-indexed (BI), particiona o horizonte de planejamento em períodos de tempos de mesmo tamanho (buckets). O tamanho dos buckets é um par âmetro que varia de acordo com a instância e influencia o porte do modelo, podendo assumir valores entre 1 e o menor tempo de processamento das tarefas. Quanto maior o tamanho do bucket, menor é o número de buckets criados e, consequentemente, menor o porte do modelo. A formulação proposta é testada em instâncias reais referentes ao problema de programação de sondas para construção de poços de petróleo de uma indústria brasileira de óleo e gás. A fim de avaliar os resultados obtidos pela formulação BI, a formulação clássica time-indexed (TI) foi também implementada para comparação dos tempos computacionais e qualidade da solução. Os resultados da formulação proposta apontam um melhor desempenho nas instâncias testadas, reduzindo o tempo computacional em todos os casos e resolvendo instâncias de grande porte não resolvidas pela formulação TI. / [en] Machine scheduling is a decision-making process that plays an important role in most manufacturing and service industries. This dissertation tackles a nonpreemptive identical parallel machine scheduling problem, considering release dates, deadlines, precedences, eligibility, and machine availability constraints. To solve this problem, a mixed-integer linear programming formulation is proposed. The new model, called bucketindexed, partitions the planning horizon in periods of equal length (buckets). The bucket size is a parameter which varies according to instances and influences the model size, assuming values between 1 and the shortest processing time of jobs. The larger the bucket size, the smaller is the number of buckets created and, consequently, the smaller the model size. The proposed formulation is tested in real instances of the rig scheduling problem for a Brazilian oil and gas industry. To evaluate the results obtained by the BI formulation, the classical time-indexed (TI) formulation was also implemented for comparison of computational times and solution quality. The results of the proposed formulation highlight a better performance in all the tested instances, reducing computational time in all cases and solving large instances unsolvable by the TI formulation.

Amid the global efforts surrounding United Nations' Millennium Development Goal Target 7c to improve access to safe and sustainable drinking water among populations who lack this resource, it has become essential to monitor and evaluate progress. Development initiatives working to achieve improved drinking water access often introduce appropriate technologies designed to be sustainably owned and operated by populations in rural areas suffering from water related hardships. It is valuable to thoroughly examine the degree to which these technologies satisfy intended objectives and affect user experienced water access. The accurate reflection of impact and progress can be complex, as the evaluation of water supplies can be made based on a variety of indicators that range from "improved' or "unimproved" water source definitions to measurements of the capacity of a source to satisfy desirable conditions related to water quality, quantity, reliability, or user's preference. The goals of this research are to conduct a comprehensive analysis of the effects of two appropriate technologies on local water access using an assortment of methods including: water quality analysis, visual and manual inspection, user interviews, and an overall sustainability analysis. In Panama, the indigenous Ng[oumlaut]be people in the [Ntilde][oumlaut]Kribo coastal area are a group disproportionately affected by a lack of improved access to drinking water and challenges to the feasibility of piped gravity fed water systems that typically serve the rest of the country. An NGO aiming to ameliorate this situation introduced two improved groundwater supply technologies to the region: bailers and EMAS hand pumps. This study assesses the comparative performance of these systems and evaluates the respective performances of existing water sources, using the wide variety of quantitative and qualitative data obtained. The data collected in this investigation suggested that bailers and EMAS pumps yielded a mixed level of performance based on physical, chemical, and bacteriological water quality measurements in the shallow wells of the study environment. The technologies generally satisfied international guidelines and expected ranges based on chemical and physical parameters such as conductivity, TDS, and turbidity (with 57% of samples under 5 NTU). EMAS hand pumps demonstrated excellent bacteriological water quality with all samples indicating undetectable levels of E.coli, while bailers had a fair performance with 83% of samples falling into a range signifying intermediate to no associated health risk. When comparing the overall water quality performance between the two hand augered well systems and with existing sources, the results indicated that bailers and EMAS pumps performed similarly in all aspects except for bacteriological quality. Overall, analysis based on groupings of "improved" and "unimproved" sources yielded very little distinction between the two categories when considering chemical, physical, and bacteriological parameters. This highlights the added value of using alternative indicators such as WHO guidelines to assess water sources, despite the challenges associated with field water quality sampling. Interview data demonstrated that hand augered wells significantly improved household water access in the study area based on user considerations by providing a reliable water drinking water alternative with adequate quantities of water perceived to be clean. Accordingly, the improved water systems were integrated as a resilient water source into a socio-cultural context noting variable dependence on multiple water sources with categorized, appropriate related water uses set informally by Ng[oumlaut]be families. The overall sustainability analysis found EMAS hand pump and bailer technologies to be effective and appropriate; featuring low costs, few materials, and simple designs. Bailer systems were considered to be especially promising for applications in similar remote areas with high groundwater tables. However, the ultimate sustainability of both systems in the local context was found to be largely dependent on factors related to the development strategy adopted while implementing these systems in the [Ntilde][oumlaut]Kribo area.

Made available in DSpace on 2014-06-11T19:24:49Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-09-16Bitstream added on 2014-06-13T19:52:37Z : No. of bitstreams: 1 cunha_av_me_bauru.pdf: 643568 bytes, checksum: 725e346fe2da40a6ef73e27721425bc0 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / É corrente entre os pesquisadores a necessidade de inserção de História. Filosofia e Sociologia da Ciência no ensino de ciências, assim como esta inserção é recorrentemente apontada como uma solução para a suposta crise que invadiu o ensino nesta modalidade. Insatisfeitos com o rumo que estas pesquisas estão tomando, delineamos nosso problema de pesquisa. Explicitamos nossa concepção de educação embasada principalmente pela obra do educador Paulo Freire, ou seja, apresentamos nossa concepção de educação dialógica-problematizadora na vertente emancipadora. Fazemos uma aproximação entre a concepção freiriana de educação e o ensino de ciências, a fim de estabelecer uma concepção de ensino de ciências, bem como do ensino de física do qual compartilhamos. Nessa concepção de ensino de ciências apresentamos a finalidade pela qual pretendemos resgatar a História, Filosofia e Sociologia da Ciência, HFSC, argumentando em favor de sua inseparabilidade com a Ciência no ensino de ciências. Apresentamos a Experiência do Balde de Newton e a finalidade que a mesma teria nessa concepção. Concluímos que a construção de enunciados sobre a experiência dp Balde de Newton, através de seus consequentes pronunciamentos e sua volta problematizada ao sujeito, proporcionou aos alunos uma transformação da realidade / It is a common practi ce among researches the need of entering into History, Philosophy and Sociology of Science in science teaching, and this integration is repeatedly cited as a solution to the supposed crisis that broke into the school championship. Unhappy with the way these survey are taking, we delicated our research problem. We explicited our conception of education based mainly on the work of eductor Paulo Freire, that is, we present our vision of dialogic-problematizing education in the shed for liberation. We make a connection between the desing Freirien education and science education in order to establish a conception of science teaching and the teaching of physics which we share. In this conception of science education we present the purpose we intend redeem the History, Philosophy and Sociology of Science, HFSC, arguing for the inseparability of Science in science education. We present the experience of Newton's bucket and the the purpose that it would have this view. We conclude that the construction of statements about the experience of Newton's bucket through this consequent pronouncements and his return problematized to the subject gave the pupils a changing reality

This thesis deals with the adjustment of quit camping equipment for application on screener crusher bucket Allu SC 3-20 in order to streamline both digging into the bucket, and the actual screening. Using simulation methods in the Adams programme, forces are detected for the digging with the original suspension. Imperfections are revealed for the current full suspension and suggestions made for the new proposedsuspension. The new shape quick release mechanism is designed in CATIA modeler and the I-Deas programme provides final strength control of parts for the proposed mechanism. Finally, both variants are coMPared in terms of digging, sifting the material complexity of the design and the necessary restrictive criteria.

CFD is today a big part of the design process in hydraulic engineering and is more economical and time efficient than traditional scale models. But, there are still issues concerning the agreement with scale models in large and complex geometries. In this degree project a high head, five channeled, slotted flip bucket spillway system is analyzed with the CFD software FLUENT and compared with existing scale model results. The sought hydraulic parameters in each channel were the discharge capacity, the pressure distribution and the throw distance from the flip buckets. The discharge capacity and pressure distribution was practically equal for all five channels and only the throw distance from Channel 1 deviated from the others. The agreement with data from the scale model is quite low. The biggest error sources behind the bad agreement may depend on the lack of computational power which led to bad choice of cell size, model delimitations and simplifications. CFD models can easily be built up by people without experience in hydraulics which can lead to fatal errors when building up the model and interpreting results. Hence, long experience in CFD or verification of the numerical results with several different hydraulic parameters is the only way to guarantee qualitative results from CFD modeling.

As an important sector of the global economy, underground mining serves as the foundation for the economies of many nations. It involves the extraction of precious minerals, ores, and other geological elements. Mining requires the use of specialised machinery and equipment, such as the Load-Haul-Dump (LHD) machines, which carries out the loading, hauling and dumping of the fragmented ores. Despite the widespread use of LHDs, there still exists a knowledge gap regarding research that considers the effects of several operational, technical, and environmental factors of the LHD general performance. This master thesis focuses on analysing the Load-Haul-Dump (LHD) machine operations and it aims to provide a comprehensive understanding of the different components of an ideal LHD operation: machine performance, machine and bucket design, bucket filling and loading operation, condition of the material to be loaded, machine care, and other mining related issues, and their connections via a throughout literature review. A traditional literature review served as the foundation for the development of this thesis. This kind of review is based on recent and current investigations accesible. In order to describe the main factors affecting an LHD operation, the literature research approach included reading, assessing, and categorising the literature regarding each individual factor. The findings of this research were compiled in the form of key findings presented on a bullet point list format. The findings serve as recommendations on how the different factors analysed help with either the improvement of the LHD operation or may negatively affect the performance of said LHDs.

Background: As cloud computing has risen over the last decades, there are several cloud services accessible on the market, users may prefer to select those that are more flexible and efficient. Based on the preceding, we chose to research to evaluate cloud services in terms of which would be better for the user in terms ofgetting the needed data from the chosen website and utilizing JMeter for performance testing. If we continue our thesis study by assessing the performance of different sample users using JMeter as the testing tool, it is appropriate for our thesis research subject. In this case, the user interfaces of GCP and AWS are compared while doing several compute engine-related operations. Objectives: This thesis aims to test the website performance after deploying in two distinct cloud platforms.After the creation of instances in AWS, a domain in GCP and also the bucket, the website files are uploaded into the bucket. The GCP and AWS instances are connected to the lifestyle store website. The performance testing on the selected website is done on both services, and then comparison ofthe outcomes of our thesis research using the testing tool Jmeter is done. Methods: In these, we choose experimentation as our research methodology,and in this, the task is done in two cloud platforms in which the website will be deployed separately. The testing tool with performance testing is employed. JMeter is used to test a website’s performance in both possible services and then to gather our research results, and the visualization of the results are done in an aggregate graph, graphs and summary reports. The metrics are Throughput, average response time, median, percentiles and standard deviation. Results: The results are based on JMeter performance testing of a selected web-site between two cloud platforms. The results of AWS and GCP can be shown in the aggregate graph. The graph results are based on the testing tool to determine which service is best for users to obtain a response from the website for requested data in the shortest amount of time. We have considered 500 and 1000 users, and based on the results, we have compared the metrics throughput, average response time, standard deviation and percentiles. The 1000 user results are compared to know which cloud platform performs better. Conclusions: According to the results from the 1000 users, it can be concluded that AWS has a higher throughput than GCP and a less average response time.Thus, it can be said that AWS outperforms GCP in terms of performance.

The thesis is devoted to determining the parameters of the bucket to increase productivity of dredgers while mining deep-water organic-mineral sediments. It was achieved by increasing the fill factor through determining the rational geometrical parameters of the bucket. Analytical dependencies of the rational height and length of the bucket on the cutting parameters and physical-and-mechanical properties of the excavated sediments were determined. Expressions for defining forces while digging plasticity water-saturated soils were developed. Experimental investigations of the process of digging deep-water organic-mineral sediments in laboratory conditions and in the real conditions of operating single-bucket dredger in the Black Sea at the depth of 1885 m were carried out. The technique for calculation of the bucket\'s parameters was developed.