Esta pesquisa visa avaliar os processos de catalogação das obras que compõem um museu de arte, tendo o MAC USP como estudo de caso e, como referências, as ferramentas de catálogos on-line, como a do MoMA, e as ferramentas utilizadas pelo Museu Nacional de Belas Artes do Rio de Janeiro (MNBA), pela Pinacoteca do Estado de São Paulo e pelo MASP, que fazem uso do sistema de gerenciamento Donato. Busca-se refletir sobre a gestão de coleções e os procedimentos de documentação das obras, incluindo o uso de fichas catalográficas. / This research aims to evaluate the cataloging processes of the works that comprise an art museum, focusing on MAC USP (Contemporary Art Museum of University of São Paulo) as a case study. Online catalog tools, such as of the MoMA (The Museum of Modern Art, New York), as well as the Donato collection management system, used by the National Fine Arts Museum of Rio de Janeiro (MNBA), the Pinacoteca of State of São Paulo and the MASP (Art Museum of São Paulo Assis Chateaubriand) were considered as reference. It is expected that this study will contribute to reflection upon the management of collections and the procedures for documentation of art works, including the use of catalog cards.

A aeração artificial em meio líquido visa suprir a baixa concentração de oxigênio dissolvido em ambientes deficientes deste, sendo um processo comumente aplicado na área de tratamento de efluentes por processos aeróbios. Uma forma de produzir aeração artificial é através de difusores submersos no fundo de um tanque com formação de bolhas, que ascendem e transferem seu oxigênio ao longo da coluna dágua. Para simular e melhor entender este processo e sua fluidodinâmica, um modelo inicial simplificado foi proposto, baseado em conceitos teóricos e equações que representem o fenômeno, como a de dispersão de bolhas, velocidades médias e concentração de oxigênio dissolvido. Foi considerado para realização dos cálculos um tanque retangular, com entrada de água a esquerda e saída de água a direita, com superfície sólida ao fundo e superfície livre acima, em contato com o ar. As equações de transporte de massa foram discretizadas no tempo, utilizando a técnica de Crank-Nicolson e no espaço segundo metodologia de diferenças centrais, solucionadas posteriormente por meio de técnicas iterativas do tipo Gauss-Seidel. As equações de transporte de quantidade de movimento foram resolvidas com o método MAC, explícito nas velocidades do fluido e implícito na pressão, para fornecer o campo de velocidade e pressão. A equação de que fornece o perfil de espalhamento das bolhas foi tomada como uma Equação Gaussiana de dispersão bidimensional. A implementação computacional necessária para aplicação das abordagens foi no ambiente de programação MATLAB. O método MAC e a técnica Crank-Nicolson apresentaram resultados satisfatórios para simulações rápidas e noção do comportamento do fluido e da concentração de oxigênio dissolvido. / The artificial aeration in aqueous mean aims to supply low concentration of dissolved oxygen in deficient atmospheres of it. This process is commonly applied in the field of wastewater treatment by aerobic processes. One way to produce artificial aeration is through diffusers submerged at the bottom of a tank with the formation of bubbles, which ascend and transfer its oxygen throughout the water column. To simulate and better understand this process and its fluid dynamics, a simplified initial model was proposed based on theoretical concepts and equations that represent the phenomenon, as the dispersion of bubbles, average speeds and dissolved oxygen concentration. It was considered for the calculations one rectangular tank with the water inlet and water outlet from left to right, with solid surface to the bottom and free surface at the top in contact with air. The mass transport equations were discretized in time, using the Crank-Nicolson technique and in space according to the methodology of central differences, subsequently resolved by Gauss-Seidel technique iterative. The transport equations of momentum were solved with the MAC method, explicit on the velocities of the fluid and implicit on pressure, to afford the velocity field and pressure. The equation which provides the spreading profiles of bubbles was taken as a two-dimensional Gaussian dispersion equation. The computational implementation necessary for application of the approaches was the programming environment MATLAB. The MAC method and Crank- Nicolson technique showed satisfactory results for quick simulations and notion of the behavior of the fluid and the concentration of dissolved oxygen.

Esta pesquisa visa avaliar os processos de catalogação das obras que compõem um museu de arte, tendo o MAC USP como estudo de caso e, como referências, as ferramentas de catálogos on-line, como a do MoMA, e as ferramentas utilizadas pelo Museu Nacional de Belas Artes do Rio de Janeiro (MNBA), pela Pinacoteca do Estado de São Paulo e pelo MASP, que fazem uso do sistema de gerenciamento Donato. Busca-se refletir sobre a gestão de coleções e os procedimentos de documentação das obras, incluindo o uso de fichas catalográficas. / This research aims to evaluate the cataloging processes of the works that comprise an art museum, focusing on MAC USP (Contemporary Art Museum of University of São Paulo) as a case study. Online catalog tools, such as of the MoMA (The Museum of Modern Art, New York), as well as the Donato collection management system, used by the National Fine Arts Museum of Rio de Janeiro (MNBA), the Pinacoteca of State of São Paulo and the MASP (Art Museum of São Paulo Assis Chateaubriand) were considered as reference. It is expected that this study will contribute to reflection upon the management of collections and the procedures for documentation of art works, including the use of catalog cards.

Energy consumption and network latency are important issues in wireless sensor networks. The mechanism duty cycling is generally used in wireless sensor networks for avoiding energy consumption due to idle listening. Duty cycling, however, also introduces additional latency in communication among sensors. Some protocols have been proposed to work in wireless sensor networks with duty cycling, such as S-MAC and DW-MAC. Those protocols also tried to make efficient channel utilization and to mitigate the chance of packet collision and the network latency increase resulting from collision. DW-MAC was also designed to tolerate bursty and high traffic loads without increasing energy consumption, by spreading packet transmission and node wakeup times during a cycle. Some performance comparison between S-MAC and DW-MAC has been done in previous work; however, this comparison was performed in the ns-2 simulator only. In the real world, there are further issues not considered or discussed in the simulation, and some of those issues contribute significant influences to the MAC protocol performance. In this work, I implemented both S-MAC and DW-MAC physically on MICAz sensor motes and compared their performance through experiments. Through my implementation, experiments, and performance evaluation, hardware properties and issues that were not addressed in the previous work are presented, and their impacts on the performance are shown and discussed. I also simulated S-MAC and DW-MAC on ns-2 to give a mutual validation of the experimental results and my interpretation of the results. The experiences of physical implementations presented in this work can contribute new information and insights for helping in future MAC protocol design and implementation in wireless sensor networks.

International Telemetering Conference Proceedings / October 18-21, 2004 / Town & Country Resort, San Diego, California / Sensor network applications typically require continuous monitoring of physical phenomena for extended periods of time under severe energy resource constraints. Accordingly, design considerations for sensor Media Access Control (MAC) protocols depart significantly from those of traditional wireless MAC protocols that largely ignore the energy factor. In this paper, we reexamine the design space of wireless sensor MAC protocols and modify IEEE 802.11 Distributed Coordination Function (DCF) to incorporate energy-adaptive contention mechanisms for prolonging sensor lifetime. Performance of the proposed schemes is evaluated with DCF as a baseline and results indicate the benefits of energy-aware mechanisms for sensor MAC protocols.

The design, test and implementation of a custom Ethernet card for embedded microcontrollers is described. The development of this Ethernet card is an educational effort to understand the various intricacies involved in constructing an Ethernet solution for embedded microcontrollers. The secondary motivation is to research the areas of the design can be ruggedized for high temperature and pressure applications. This report covers in detail the overall effort to which Henry Chang contributed. / text

隨著IEEE 802.11無線傳輸頻率的快速發展，而傳輸距離卻隨著縮短，使得我們考慮多跳接的傳輸方式來擴展通訊的範圍。但是在IEEE 802.11 的多跳接無線網路中並沒有服務品質的保證，而且在傳輸上的效能不高，因此我們希望在IEEE 802.11 多跳接的無線網路中改善傳輸效能且提供服務品質保證。在這篇論文中，我們提出了一個安排MAC存取的方法，來達到服務品質保證。我們使用一個樹狀架構來建構這個無線網路並且運作訊標繞樹的動作來建立我們的分離集合，而分離集合提供我們安排無衝突傳輸。當訊務流在這個網路中產生，我們的方法能夠有效的安排MAC存取並且保證不同類型訊務之品質。我們同時也提供一種適應性安排機制，來有效利用整個網路的效能，並且避免重新安排整個網路的MAC存取規畫，來維持網路品質在適當的滿意度。實驗結果顯示我們在多跳接的無線網路中有效的達到服務品質保證。 / With fast development of radio frequency, the wireless communication in IEEE 802.11 is growing up to high transmission rate (802.11g). However the distance of transmission decreases when wave frequency increases. Thus there is growing need to extend communication distance through multihop transmissions. But there is no QoS in IEEE 802.11 Multihop Wireless Networks; it has poor performance on transmission. Thus we are motivated to provide QoS in IEEE 802.11 Multihop Wireless Networks. In This Thesis, we propose a MAC Access Scheduling Scheme to support guaranteed QoS in IEEE 802.11 Multihop Wireless Networks. We use a tree-based architecture to construct the network and form the operation of token traversal. Token traversal operation builds the Disjoint Set to support scheduling collision-free transmission. When traffic is generated to the network, our scheme provides efficient schedule of MAC access and guarantee the QoS of different types of traffic. We also provide a adaptive scheduling to utilize the network performance and avoid the overhead of re-schedule to maintain the network quality at a satisfied level. The simulation results show we achieve the network QoS efficiently and provide guaranteed QoS.

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The increased globalisation of information and communication technologies has transformed the world into the internet of things (IoT), which is accomplished within the resources of wireless sensor networks (WSNs). Therefore, the future IoT networks will consist of high density of connected nodes that suffer from resource limitation, especially the energy one, and distribute randomly in a harsh and large-scale areas. Accordingly, the contributions in this thesis are focused on the development of energy efficient design protocols based on optimisation algorithms, with consideration of the resource limitations, adaptability, scalability, node density and random distribution of node density in the geographical area. One MAC protocol and two routing protocols, with both a static and mobile sink, are proposed. The first proposed protocol is an energy efficient hybrid MAC protocol with dynamic sleep/wake-up extension to the IEEE 802.15.4 MAC, namely, HSW-802.15.4. The model automates the network by enabling it to work exibly in low and high-density networks with a lower number of collisions. A frame structure that offers an enhanced exploitation for the TDMA time slots (TDMAslots) is provided. To implement these enhanced slots exploitation, this hybrid protocol rst schedules the TDMAsslots, and then allocates each slot to a group of devices. A three-dimensional Markov chain is developed to display the proposed model in a theoretical manner. Simulation results show an enhancement in the energy conservation by 40% - 60% in comparison to the IEEE 802.15.4 MAC protocol. Secondly, an efficient centralised clustering-based whale optimisation algorithm (CC- WOA) is suggested, which employs the concept of software de ned network (SDN) in its mechanism. The cluster formulation process in this algorithm considers the random di- versi cation of node density in the geographical area and involves both sensor resource restrictions and the node density in the tness function. The results offer an efficient con- servation of energy in comparison to other protocols. Another clustering algorithm, called centralised load balancing clustering algorithm (C-LBCA), is also developed that uses par- ticle swarm optimisation (PSO) and presents robust load-balancing for data gathering in IoT. However, in large scale networks, the nodes, especially the cluster heads (CHs), suffer from a higher energy exhaustion. Hence, in this thesis, a centralised load balanced and scheduling protocol is proposed utilising optimisation algorithms for large scale IoT net- works, named, optimised mobile sink based load balancing (OMS-LB). This model connects the impact of the Optimal Path for the MS (MSOpath) determination and the adjustable set of data aggregation points (SDG) with the cluster formulation process to de ne an op- timised routing protocol suitable for large scale networks. Simulation results display an improvement in the network lifespan of up to 54% over the other approaches.

This paper describes an adaptive service differentiation scheme for QoS enhancement in IEEE 802.11 wireless ad-hoc networks. Our approach is called Dynamic Age-Dependent Backoff (DADB) which is derived from the ADB scheme and aims to improve the ADB scheme when the traffic load is high. Improvement of our scheme are provisioned by adjusting the size of the persistent factor of high traffic categories taking into account both age time of frame and network conditions. We evaluate the performance of DADB through simulations and compare it with the ADB scheme proposed in the 802.11e. Results show that our scheme DADB is similar to ADB scheme which can improve the delay and jitter in wireless network. Especially at high traffic load conditions, DADB outperforms the basic ADB: our scheme improve the throughput of high priority traffic category and decrease collision rate when traffic load is heavy.