Mujeres indígenas mostrando las mantas y pecheras tradicionales de la cultura Wayúu Guajira.

12 hojas : ilustraciones, fotografías a color.

Feasibility of combined wind-wave energy platforms

The European Union has set out an ambitious 20% target for renewable energy use by 2020. It is expected that this will be met mainly by wind energy. Looking towards 2050, reductions in greenhouse gas emissions of 80-95% are to be sought. Given the issues securing this target in the transport and agriculture sectors, it may only be possible to achieve this target if the power sector is carbon neutral well in advance of 2050. This has permitted the vast expansion of offshore renewables, wind, wave and tidal energy. Offshore wind has undergone rapid development in recent years however faces significant challenges up to 2020 to ensure commercial viability without the need for government subsidies. Wave energy is still in the very early stages of development so as yet there has been no commercial roll out. As both of these technologies are to face similar challenges in ensuring they are a viable alternative power generation method to fossil fuels, capitalising on the synergies is potentially a significant cost saving initiative. The advent of hybrid solutions in a variety of configurations is the subject of this thesis. A singular wind-wave energy platform embodies all the attributes of a hybrid system, including sharing space, transmission infrastructure, O&M activities and a platform/foundation. This configuration is the subject of this thesis, and it is found that an OWC Array platform with multi-MegaWatt wind turbines is a technically feasible, and potentially an economically feasible solution in the long term. Methods of design and analysis adopted in this thesis include numerical and physical modelling of power performance, structural analysis, fabrication cost modelling, simplified project economic modelling and time domain reliability modelling of a 210MW hybrid farm. The application of these design and analysis methods has resulted in a hybrid solution capable of producing energy at a cost between €0.22/kWh and €0.31/kWh depending on the source of funding for the project. Further optimisation through detailed design is expected to lower this further. This thesis develops new and existing methods of design and analysis of wind and wave energy devices. This streamlines the process of early stage development, while adhering to the widely adopted Concept Development Protocol, to develop a technically and economically feasible, combined wind-wave energy hybrid solution.

permGPU: Using graphics processing units in RNA microarray association studies.

BACKGROUND: Many analyses of microarray association studies involve permutation, bootstrap resampling and cross-validation, that are ideally formulated as embarrassingly parallel computing problems. Given that these analyses are computationally intensive, scalable approaches that can take advantage of multi-core processor systems need to be developed. RESULTS: We have developed a CUDA based implementation, permGPU, that employs graphics processing units in microarray association studies. We illustrate the performance and applicability of permGPU within the context of permutation resampling for a number of test statistics. An extensive simulation study demonstrates a dramatic increase in performance when using permGPU on an NVIDIA GTX 280 card compared to an optimized C/C++ solution running on a conventional Linux server. CONCLUSIONS: permGPU is available as an open-source stand-alone application and as an extension package for the R statistical environment. It provides a dramatic increase in performance for permutation resampling analysis in the context of microarray association studies. The current version offers six test statistics for carrying out permutation resampling analyses for binary, quantitative and censored time-to-event traits.

Autobiographical memories of anxiety-related experiences.

Ninety-nine undergraduate students retrieved three memories associated with each of the five emotional experiences: panic, trauma, worry, social anxiety, and feeling content. Subsequently, they answered 24 questions assessing properties of each memory, including the vividness and perceived accuracy of the memories and sensory, emotional, and anxiety-related experiences during retrieval. Memories were coded for affective tone and specificity. Results indicated that panic-related and trauma-related memories were rated similarly as content memories, but that they generally were associated with more imagery and emotional experiencing than worry-related or social anxiety-related memories. Participants experienced panic and worry symptoms to the greatest degree when they retrieved panic-related and trauma-related memories. All anxiety-related memories were characterized by more negative tone than content memories. Panic-related and trauma-related memories were more specific than worry-related, social anxiety-related, and content memories. These findings can explain partially why individuals with some, but not all, anxiety disorders experience enhanced memory for threatening material.

Building temporal constraints into knowledge bases for process control: an examination [Reply to author's reply]

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Lifetime assessment of electronic components for high reliability aerospace applications

This paper details a modelling approach for assessing the in-service (field) reliability and thermal fatigue life-time of electronic package interconnects for components used in the assembly of an aerospace system. The Finite Element slice model of a Plastic Ball Grid Array (PBGA) package and suitable energy based damage models for crack length predictions are used in this study. Thermal fatigue damage induced in tin-lead solder joints are investigated by simulating the crack growth process under a set of prescribed field temperature profiles that cover the period of operational life. The overall crack length in the solder joint for all different thermal profiles and number of cycles for each profile is predicted using a superposition technique. The effect of using an underfill is also presented. A procedure for verifying the field lifetime predictions for the electronic package by using reliability assessment under Accelerated Thermal Cycle (ATC) testing is also briefly outlined.

An ontological characterization of time-series and state-sequences for data mining

Time-series and sequences are important patterns in data mining. Based on an ontology of time-elements, this paper presents a formal characterization of time-series and state-sequences, where a state denotes a collection of data whose validation is dependent on time. While a time-series is formalized as a vector of time-elements temporally ordered one after another, a state-sequence is denoted as a list of states correspondingly ordered by a time-series. In general, a time-series and a state-sequence can be incomplete in various ways. This leads to the distinction between complete and incomplete time-series, and between complete and incomplete state-sequences, which allows the expression of both absolute and relative temporal knowledge in data mining.

Does culture affect a brand's personality?

Global branding brings with it exposure to an increasingly culturally-diverse audience. Examples of Islamic finance products being consumed by non-Muslims, and designer labels being adopted, by those outside of their intended target audience; seem to suggest that brands are being shaped more and more by consumers. Within current literature on branding, and cross-cultural consumer behaviour; there appears to have emerged a difference of opinion - as to whether a consumer’s culture has any bearing on their decision making; or subsequent influence brand personalities. The purpose of this paper is to present existing evidence; as a basis for undertaking future research.

Mobile authoring of open educational resources for authentic learning scenarios

The proliferation of smartphones in the last decade and the number of publications in the field of authoring systems for computer-assisted learning depict a scenario that needs to be explored in order to facilitate the scaffolding of learning activities across contexts. Learning resources are traditionally designed in desktop-based authoring systems where the context is mostly restricted to the learning objective, capturing relevant case characteristics, or virtual situation models. Mobile authoring tools enable learners and teachers to foster universal access to educational resources not only providing channels to share, remix or re-contextualize these, but also capturing the context in-situ and in-time. As a further matter, authoring educational resources in a mobile context is an authentic experience where authors can link learning with their own daily life activities and reflections. The contribution of this manuscript is fourfold: first, the main barriers for ubiquitous and mobile authoring of educational resources are identified; second, recent research on mobile authoring tools is reviewed, and 10 key shortcomings of current approaches are identified; third, the design of a mobile environment to author educational resources (MAT for ARLearn) is presented, and the results of an evaluation of usability and hedonic quality are presented; fourth, conclusions and a research agenda for mobile authoring are discussed.