863 resultados para set based design


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In the current Cambodian higher education sector, there is little regulation of standards in curriculum design of undergraduate degrees in English language teacher education. The researcher, in the course of his professional work in the Curriculum and Policy Office at the Department of Higher Education, has seen evidence that most universities tend to copy their curriculum from one source, the curriculum of the Institute of Foreign Languages, the Royal University of Phnom Penh. Their programs fail to impose any entry standards, accepting students who pass the high school exam without any entrance examination. It is possible for a student to enter university with satisfactory scores in all subjects but English. Therefore, not many graduates are able to fulfil the professional requirements of the roles they are supposed to take. Neau (2010) claims that many Cambodian EFL teachers do not reach a high performance standard due to their low English language proficiency and poor background in teacher education. The main purpose of this study is to establish key guidelines for developing curricula for English language teacher education for all the universities across the country. It examines the content of the Bachelor‘s degree of Education in Teaching English as a Foreign Language (B Ed in TEFL) and Bachelor‘s degree of Arts in Teaching English to Speakers of Other Languages (BA in TESOL) curricula adopted in Cambodian universities on the basis of criteria proposed in current curriculum research. It also investigates the perspectives of Cambodian EFL teachers on the areas of knowledge and skill they need in order to perform their English teaching duties in Cambodia today. The areas of knowledge and skill offered in the current curricula at Cambodian higher education institutions (HEIs), the framework of the knowledge base for EFL teacher education and general higher education, and the areas of knowledge and skill Cambodian EFL teachers perceive to be important, are compared so as to identify any gaps in the current English language teacher education curricula in the Cambodian HEIs. The existence of gaps show what domains of knowledge and skill need to be included in the English language teacher education curricula at Cambodian HEIs. These domains are those identified by previous curriculum researchers in both general and English language teacher education at tertiary level. Therefore, the present study provides useful insights into the importance of including appropriate content in English language teacher education curricula. Mixed methods are employed in this study. The course syllabi and the descriptions within the curricula in five Cambodian HEIs are analysed qualitatively based on the framework of knowledge and skills for EFL teachers, which is formed by looking at the knowledge base for second language teachers suggested by the methodologists and curriculum specialists whose work is elaborated on the review of literature. A quantitative method is applied to analyse the perspectives of 120 Cambodian EFL teachers on areas of knowledge and skills they should possess. The fieldwork was conducted between June and August, 2014. The analysis reveals that the following areas are included in the curricula at the five universities: communication skills, general knowledge, knowledge of teaching theories, teaching skills, pedagogical reasoning and decision making skills, subject matter knowledge, contextual knowledge, cognitive abilities, and knowledge of social issues. Additionally, research skills are included in three curricula while society and community involvement is in only one. Further, information and communication technology, which is outlined in the Education Strategies Plan (2006-2010), forms part of four curricula while leadership skills form part of two. This study demonstrates ultimately that most domains that are directly and indirectly related to language teaching competence are not sufficiently represented in the current curricula. On the basis of its findings, the study concludes with a set of guidelines that should inform the design and development of TESOL and TEFL curricula in Cambodia.

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O presente projeto de investigação, propõe compreender a cultura visual contemporânea do design do selo postal português, de 2001 a 2013, considerando os avanços e os novos meios tecnológicos digitais. Para isso, partiu-se da história do selo postal como objeto de testemunho histórico, cultural e visual repleto de valores duradouros e possuidores de uma linguagem gráfica distinta. A esse conjunto de caraterísticas que determinam o selo postal, as mesmas, representam um grau de importância associados à história e à cultura de um país, evidenciando uma linguagem característica da vida social e da época que se encontra, que ao longo dos anos possuem valores de importância e sentimento para a humanidade. Primeiramente, procedeu-se a uma pesquisa exaustiva sobre os principais designers e ateliers portugueses, quer realizada em livros de coleções dos CTT, quer na internet em motores de busca. Seguidamente, realizou-se uma análise geral sobre a sintaxe da linguagem visual, baseada no trabalho de Donis A. Dondis (2003), declinada sobre a comunicação visual no design, para este caso, nos selos postais. Partindo dessa análise, posteriormente, efetuou-se a criação de uma emissão de selos postais juntamente com a tecnologia da realidade aumentada, tendo como base a temática centrada na cidade do Porto e que pode ser repercutida em diferentes cidades do país “Uma visita portuguesa com certeza”. Com este projeto conseguiu-se demonstrar e implementar uma tecnologia digital a um artefacto de cariz físico, usualmente, apresentado em suporte papel. O estudo pretende assim, contribuir para a inovação ao nível do design filatélico e histórico do selo postal português, tendo como base o uso dessa tecnologia.

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This thesis presents approximation algorithms for some NP-Hard combinatorial optimization problems on graphs and networks; in particular, we study problems related to Network Design. Under the widely-believed complexity-theoretic assumption that P is not equal to NP, there are no efficient (i.e., polynomial-time) algorithms that solve these problems exactly. Hence, if one desires efficient algorithms for such problems, it is necessary to consider approximate solutions: An approximation algorithm for an NP-Hard problem is a polynomial time algorithm which, for any instance of the problem, finds a solution whose value is guaranteed to be within a multiplicative factor of the value of an optimal solution to that instance. We attempt to design algorithms for which this factor, referred to as the approximation ratio of the algorithm, is as small as possible. The field of Network Design comprises a large class of problems that deal with constructing networks of low cost and/or high capacity, routing data through existing networks, and many related issues. In this thesis, we focus chiefly on designing fault-tolerant networks. Two vertices u,v in a network are said to be k-edge-connected if deleting any set of k − 1 edges leaves u and v connected; similarly, they are k-vertex connected if deleting any set of k − 1 other vertices or edges leaves u and v connected. We focus on building networks that are highly connected, meaning that even if a small number of edges and nodes fail, the remaining nodes will still be able to communicate. A brief description of some of our results is given below. We study the problem of building 2-vertex-connected networks that are large and have low cost. Given an n-node graph with costs on its edges and any integer k, we give an O(log n log k) approximation for the problem of finding a minimum-cost 2-vertex-connected subgraph containing at least k nodes. We also give an algorithm of similar approximation ratio for maximizing the number of nodes in a 2-vertex-connected subgraph subject to a budget constraint on the total cost of its edges. Our algorithms are based on a pruning process that, given a 2-vertex-connected graph, finds a 2-vertex-connected subgraph of any desired size and of density comparable to the input graph, where the density of a graph is the ratio of its cost to the number of vertices it contains. This pruning algorithm is simple and efficient, and is likely to find additional applications. Recent breakthroughs on vertex-connectivity have made use of algorithms for element-connectivity problems. We develop an algorithm that, given a graph with some vertices marked as terminals, significantly simplifies the graph while preserving the pairwise element-connectivity of all terminals; in fact, the resulting graph is bipartite. We believe that our simplification/reduction algorithm will be a useful tool in many settings. We illustrate its applicability by giving algorithms to find many trees that each span a given terminal set, while being disjoint on edges and non-terminal vertices; such problems have applications in VLSI design and other areas. We also use this reduction algorithm to analyze simple algorithms for single-sink network design problems with high vertex-connectivity requirements; we give an O(k log n)-approximation for the problem of k-connecting a given set of terminals to a common sink. We study similar problems in which different types of links, of varying capacities and costs, can be used to connect nodes; assuming there are economies of scale, we give algorithms to construct low-cost networks with sufficient capacity or bandwidth to simultaneously support flow from each terminal to the common sink along many vertex-disjoint paths. We further investigate capacitated network design, where edges may have arbitrary costs and capacities. Given a connectivity requirement R_uv for each pair of vertices u,v, the goal is to find a low-cost network which, for each uv, can support a flow of R_uv units of traffic between u and v. We study several special cases of this problem, giving both algorithmic and hardness results. In addition to Network Design, we consider certain Traveling Salesperson-like problems, where the goal is to find short walks that visit many distinct vertices. We give a (2 + epsilon)-approximation for Orienteering in undirected graphs, achieving the best known approximation ratio, and the first approximation algorithm for Orienteering in directed graphs. We also give improved algorithms for Orienteering with time windows, in which vertices must be visited between specified release times and deadlines, and other related problems. These problems are motivated by applications in the fields of vehicle routing, delivery and transportation of goods, and robot path planning.

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Considerable interest in renewable energy has increased in recent years due to the concerns raised over the environmental impact of conventional energy sources and their price volatility. In particular, wind power has enjoyed a dramatic global growth in installed capacity over the past few decades. Nowadays, the advancement of wind turbine industry represents a challenge for several engineering areas, including materials science, computer science, aerodynamics, analytical design and analysis methods, testing and monitoring, and power electronics. In particular, the technological improvement of wind turbines is currently tied to the use of advanced design methodologies, allowing the designers to develop new and more efficient design concepts. Integrating mathematical optimization techniques into the multidisciplinary design of wind turbines constitutes a promising way to enhance the profitability of these devices. In the literature, wind turbine design optimization is typically performed deterministically. Deterministic optimizations do not consider any degree of randomness affecting the inputs of the system under consideration, and result, therefore, in an unique set of outputs. However, given the stochastic nature of the wind and the uncertainties associated, for instance, with wind turbine operating conditions or geometric tolerances, deterministically optimized designs may be inefficient. Therefore, one of the ways to further improve the design of modern wind turbines is to take into account the aforementioned sources of uncertainty in the optimization process, achieving robust configurations with minimal performance sensitivity to factors causing variability. The research work presented in this thesis deals with the development of a novel integrated multidisciplinary design framework for the robust aeroservoelastic design optimization of multi-megawatt horizontal axis wind turbine (HAWT) rotors, accounting for the stochastic variability related to the input variables. The design system is based on a multidisciplinary analysis module integrating several simulations tools needed to characterize the aeroservoelastic behavior of wind turbines, and determine their economical performance by means of the levelized cost of energy (LCOE). The reported design framework is portable and modular in that any of its analysis modules can be replaced with counterparts of user-selected fidelity. The presented technology is applied to the design of a 5-MW HAWT rotor to be used at sites of wind power density class from 3 to 7, where the mean wind speed at 50 m above the ground ranges from 6.4 to 11.9 m/s. Assuming the mean wind speed to vary stochastically in such range, the rotor design is optimized by minimizing the mean and standard deviation of the LCOE. Airfoil shapes, spanwise distributions of blade chord and twist, internal structural layup and rotor speed are optimized concurrently, subject to an extensive set of structural and aeroelastic constraints. The effectiveness of the multidisciplinary and robust design framework is demonstrated by showing that the probabilistically designed turbine achieves more favorable probabilistic performance than those of the initial baseline turbine and a turbine designed deterministically.

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Recent developments in automation, robotics and artificial intelligence have given a push to a wider usage of these technologies in recent years, and nowadays, driverless transport systems are already state-of-the-art on certain legs of transportation. This has given a push for the maritime industry to join the advancement. The case organisation, AAWA initiative, is a joint industry-academia research consortium with the objective of developing readiness for the first commercial autonomous solutions, exploiting state-of-the-art autonomous and remote technology. The initiative develops both autonomous and remote operation technology for navigation, machinery, and all on-board operating systems. The aim of this study is to develop a model with which to estimate and forecast the operational costs, and thus enable comparisons between manned and autonomous cargo vessels. The building process of the model is also described and discussed. Furthermore, the model’s aim is to track and identify the critical success factors of the chosen ship design, and to enable monitoring and tracking of the incurred operational costs as the life cycle of the vessel progresses. The study adopts the constructive research approach, as the aim is to develop a construct to meet the needs of a case organisation. Data has been collected through discussions and meeting with consortium members and researchers, as well as through written and internal communications material. The model itself is built using activity-based life cycle costing, which enables both realistic cost estimation and forecasting, as well as the identification of critical success factors due to the process-orientation adopted from activity-based costing and the statistical nature of Monte Carlo simulation techniques. As the model was able to meet the multiple aims set for it, and the case organisation was satisfied with it, it could be argued that activity-based life cycle costing is the method with which to conduct cost estimation and forecasting in the case of autonomous cargo vessels. The model was able to perform the cost analysis and forecasting, as well as to trace the critical success factors. Later on, it also enabled, albeit hypothetically, monitoring and tracking of the incurred costs. By collecting costs this way, it was argued that the activity-based LCC model is able facilitate learning from and continuous improvement of the autonomous vessel. As with the building process of the model, an individual approach was chosen, while still using the implementation and model building steps presented in existing literature. This was due to two factors: the nature of the model and – perhaps even more importantly – the nature of the case organisation. Furthermore, the loosely organised network structure means that knowing the case organisation and its aims is of great importance when conducting a constructive research.

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Aromatic thermosetting copolyester (ATSP) has promise in high-temperature applications. It can be employed as a bulk polymer, as a coating and as a matrix for carbon fiber composites (ATSP/C composites). This work focuses on the applications of high performance ATSP/C composites. The morphology of the ATSP matrix in the presence of carbon fiber was studied. The effect of liquid crystalline character of starting oligomers used to prepare ATSP on the final crystal structure of the ATSP/C composite was evaluated. Matrices obtained by crosslinking of both liquid crystalline oligomers (ATSP2) and non-liquid crystalline oligomers (ATSP1) tend to crystallize in presence of carbon fibers. The crystallite size of ATSP2 is 4 times that of ATSP1. Composites made from ATSP2 yield tougher matrices compared to those made from ATSP1. Thus toughened matrices could be achieved without incorporating any additives by just changing the morphology of the final polymer. The flammability characteristics of ATSP were also studied. The limiting oxygen index (LOI) of bulk ATSP was found to be 40% whereas that of ATSP/C composites is estimated to be 85%. Thus, ATSP shows potential to be used as a flame resistant material, and also as an aerospace reentry shield. Mechanical properties of the ATSP/C composite were characterized. ATSP was observed to bond strongly with reinforcing carbon fibers. The tensile strength, modulus and shear modulus were comparable to those of conventionally used high temperature epoxy resins. ATSP shows a unique capability for healing of interlaminar cracks on application of heat and pressure, via the Interchain Transesterification Reaction (ITR). ITR can also be used for reduction in void volume and healing of microcracks. Thus, ATSP resin systems provide a unique intrinsic repair mechanism compared to any other thermosetting systems in use today. Preliminary studies on measurement of residual stresses for ATSP/C composites indicate that the stresses induced are much lower than that in epoxy/C composites. Thermal fatigue testing suggests that ATSP shows better resistance to microcracking compared to epoxy resins.

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Requirements specification has long been recognized as critical activity in software development processes because of its impact on project risks when poorly performed. A large amount of studies addresses theoretical aspects, propositions of techniques, and recommended practices for Requirements Engineering (RE). To be successful, RE have to ensure that the specified requirements are complete and correct what means that all intents of the stakeholders in a given business context are covered by the requirements and that no unnecessary requirement was introduced. However, the accurate capture the business intents of the stakeholders remains a challenge and it is a major factor of software project failures. This master’s dissertation presents a novel method referred to as “Problem-Based SRS” aiming at improving the quality of the Software Requirements Specification (SRS) in the sense that the stated requirements provide suitable answers to real customer ́s businesses issues. In this approach, the knowledge about the software requirements is constructed from the knowledge about the customer ́s problems. Problem-Based SRS consists in an organization of activities and outcome objects through a process that contains five main steps. It aims at supporting the software requirements engineering team to systematically analyze the business context and specify the software requirements, taking also into account a first glance and vision of the software. The quality aspects of the specifications are evaluated using traceability techniques and axiomatic design principles. The cases studies conducted and presented in this document point out that the proposed method can contribute significantly to improve the software requirements specification.

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INTRODUCTION: In common with much of the developed world, Scotland has a severe and well established problem with overweight and obesity in childhood with recent figures demonstrating that 31% of Scottish children aged 2-15 years old were overweight including obese in 2014. This problem is more pronounced in socioeconomically disadvantaged groups and in older children across all economic groups (Scottish Health Survey, 2014). Children who are overweight or obese are at increased risk of a number of adverse health outcomes in the short term and throughout their life course (Lobstein and Jackson-Leach, 2006). The Scottish Government tasked all Scottish Health Boards with developing and delivering child healthy weight interventions to clinically overweight or obese children in an attempt to address this health problem. It is therefore imperative to deliver high quality, affordable, appropriately targeted interventions which can make a sustained impact on children’s lifestyles, setting them up for life as healthy weight adults. This research aimed to inform the design, readiness for application and Health Board suitability of an effective primary school-based curricular child healthy weight intervention. METHODS: the process involved in conceptualising a child healthy weight intervention, developing the intervention, planning for implementation and subsequent evaluation was guided by the PRECEDE-PROCEED Model (Green and Kreuter, 2005) and the Intervention Mapping protocol (Lloyd et al. 2011). RESULTS: The outputs from each stage of the development process were used to formulate a child healthy weight intervention conceptual model then develop plans for delivery and evaluation. DISCUSSION: The Fit for School conceptual model developed through this process has the potential to theoretically modify energy balance related behaviours associated with unhealthy weight gain in childhood. It also has the potential to be delivered at a Health Board scale within current organisational restrictions.

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Secure Multi-party Computation (MPC) enables a set of parties to collaboratively compute, using cryptographic protocols, a function over their private data in a way that the participants do not see each other's data, they only see the final output. Typical MPC examples include statistical computations over joint private data, private set intersection, and auctions. While these applications are examples of monolithic MPC, richer MPC applications move between "normal" (i.e., per-party local) and "secure" (i.e., joint, multi-party secure) modes repeatedly, resulting overall in mixed-mode computations. For example, we might use MPC to implement the role of the dealer in a game of mental poker -- the game will be divided into rounds of local decision-making (e.g. bidding) and joint interaction (e.g. dealing). Mixed-mode computations are also used to improve performance over monolithic secure computations. Starting with the Fairplay project, several MPC frameworks have been proposed in the last decade to help programmers write MPC applications in a high-level language, while the toolchain manages the low-level details. However, these frameworks are either not expressive enough to allow writing mixed-mode applications or lack formal specification, and reasoning capabilities, thereby diminishing the parties' trust in such tools, and the programs written using them. Furthermore, none of the frameworks provides a verified toolchain to run the MPC programs, leaving the potential of security holes that can compromise the privacy of parties' data. This dissertation presents language-based techniques to make MPC more practical and trustworthy. First, it presents the design and implementation of a new MPC Domain Specific Language, called Wysteria, for writing rich mixed-mode MPC applications. Wysteria provides several benefits over previous languages, including a conceptual single thread of control, generic support for more than two parties, high-level abstractions for secret shares, and a fully formalized type system and operational semantics. Using Wysteria, we have implemented several MPC applications, including, for the first time, a card dealing application. The dissertation next presents Wys*, an embedding of Wysteria in F*, a full-featured verification oriented programming language. Wys* improves on Wysteria along three lines: (a) It enables programmers to formally verify the correctness and security properties of their programs. As far as we know, Wys* is the first language to provide verification capabilities for MPC programs. (b) It provides a partially verified toolchain to run MPC programs, and finally (c) It enables the MPC programs to use, with no extra effort, standard language constructs from the host language F*, thereby making it more usable and scalable. Finally, the dissertation develops static analyses that help optimize monolithic MPC programs into mixed-mode MPC programs, while providing similar privacy guarantees as the monolithic versions.

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Green roofs are a maturing application of best management practices for controlling urban stormwater runoff. The majority of green roofs are planted with drought resistant, higher plant species, such as the genus Sedum. However, other plant varieties, such as mosses, may be equally applicable. Residential roofs and natural terrestrial communities were sampled in both Maryland and Tennessee to determine moss community structure and species water composition. This served as a natural analog for potential green roof moss communities. During sampling, 21 species of moss were identified throughout the 37 total sites. The average percent moss cover and water composition across all roof sites was 40.7% and 38.6%, respectively and across all natural sites, 76.7% and 47.7%, respectively. Additional maximum water holding capacity procedures were completed on sedum and 19 of the 21 sampled moss species to assess their individual potential for stormwater absorption. Sedum species on average held 166% of their biomass in water, while moss species held 732%. The results of this study are used as a basis to propose moss species that will improve green roof performance.

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Safe operation of unmanned aerial vehicles (UAVs) over populated areas requires reducing the risk posed by a UAV if it crashed during its operation. We considered several types of UAV risk-based path planning problems and developed techniques for estimating the risk to third parties on the ground. The path planning problem requires making trade-offs between risk and flight time. Four optimization approaches for solving the problem were tested; a network-based approach that used a greedy algorithm to improve the original solution generated the best solutions with the least computational effort. Additionally, an approach for solving a combined design and path planning problems was developed and tested. This approach was extended to solve robust risk-based path planning problem in which uncertainty about wind conditions would affect the risk posed by a UAV.

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The development of robots has shown itself as a very complex interdisciplinary research field. The predominant procedure for these developments in the last decades is based on the assumption that each robot is a fully personalized project, with the direct embedding of hardware and software technologies in robot parts with no level of abstraction. Although this methodology has brought countless benefits to the robotics research, on the other hand, it has imposed major drawbacks: (i) the difficulty to reuse hardware and software parts in new robots or new versions; (ii) the difficulty to compare performance of different robots parts; and (iii) the difficulty to adapt development needs-in hardware and software levels-to local groups expertise. Large advances might be reached, for example, if physical parts of a robot could be reused in a different robot constructed with other technologies by other researcher or group. This paper proposes a framework for robots, TORP (The Open Robot Project), that aims to put forward a standardization in all dimensions (electrical, mechanical and computational) of a robot shared development model. This architecture is based on the dissociation between the robot and its parts, and between the robot parts and their technologies. In this paper, the first specification for a TORP family and the first humanoid robot constructed following the TORP specification set are presented, as well as the advances proposed for their improvement.

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The aim of this paper is to present new results on H-infinity control synthesis for time-delay linear systems. We extend the use of a finite order LTI system, called comparison system to H-infinity analysis and design. Differently from what can be viewed as a common feature of other control design methods available in the literature to date, the one presented here treats time-delay systems control design with classical numeric routines based on Riccati equations arisen from H-infinity theory. The proposed algorithm is simple, efficient and easy to implement. Some examples illustrating state and output feedback design are solved and discussed in order to put in evidence the most relevant characteristic of the theoretical results. Moreover, a practical application involving a 3-DOF networked control system is presented.

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Part 20: Health and Care Networks