840 resultados para WIDE-RANGE CURRENT MEASUREMENT


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A wide range of goals and objectives have to be taken into account in natural resources management. Defining these objectives in operational terms, including dimensions such as sustainability, productivity, and equity, is by no means easy, especially if they must capture the diversity of community and stakeholder values. This is especially true in the coastal zone where land activities affect regional marine ecosystems. In this study, the aim was firstly to identify and hierarchically organise the goals and objectives for coastal systems, as defined by local stakeholders. Two case study areas are used within the Great Barrier Reef region being Mackay and Bowen–Burdekin. Secondly, the aim was to identify similarities between the case study results and thus develop a generic set of goals to be used as a starting point in other coastal communities. Results show that overarching high-level goals have nested sub-goals that contain a set of more detailed regional objectives. The similarities in high-level environmental, governance, and socio-economic goals suggest that regionally specific objectives can be developed based on a generic set of goals. The prominence of governance objectives reflects local stakeholder perceptions that current coastal zone management is not achieving the outcomes they feel important and that there is a need for increased community engagement and co-management. More importantly, it raises the question of how to make issues relevant for the local community and entice participation in the local management of public resources to achieve sustainable environmental, social, and economic management outcomes. © 2015 Springer-Verlag Berlin Heidelberg

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When components of a propulsion system are exposed to elevated flow temperatures there is a risk for catastrophic failure if the components are not properly protected from the thermal loads. Among several strategies, slot film cooling is one of the most commonly used, yet poorly understood active cooling techniques. Tangential injection of a relatively cool fluid layer protects the surface(s) in question, but the turbulent mixing between the hot mainstream and cooler film along with the presence of the wall presents an inherently complex problem where kinematics, thermal transport and multimodal heat transfer are coupled. Furthermore, new propulsion designs rely heavily on CFD analysis to verify their viability. These CFD models require validation of their results, and the current literature does not provide a comprehensive data set for film cooling that meets all the demands for proper validation, namely a comprehensive (kinematic, thermal and boundary condition data) data set obtained over a wide range of conditions. This body of work aims at solving the fundamental issue of validation by providing high quality comprehensive film cooling data (kinematics, thermal mixing, heat transfer). 3 distinct velocity ratios (VR=uc/u∞) are examined corresponding to wall-wake (VR~0.5), min-shear (VR ~ 1.0), and wall-jet (VR~2.0) type flows at injection, while the temperature ratio TR= T∞/Tc is approximately 1.5 for all cases. Turbulence intensities at injection are 2-4% for the mainstream (urms/u∞, vrms/u∞,), and on the order of 8-10% for the coolant (urms/uc, vrms/uc,). A special emphasis is placed on inlet characterization, since inlet data in the literature is often incomplete or is of relatively low quality for CFD development. The data reveals that min-shear injection provides the best performance, followed by the wall-jet. The wall-wake case is comparably poor in performance. The comprehensive data suggests that this relative performance is due to the mixing strength of each case, as well as the location of regions of strong mixing with respect to the wall. Kinematic and thermal data show that strong mixing occurs in the wall-jet away from the wall (y/s>1), while strong mixing in the wall-wake occurs much closer to the wall (y/s<1). Min-shear cases exhibit noticeably weaker mixing confined to about y/s=1. Additionally to these general observations, the experimental data obtained in this work is analyzed to reveal scaling laws for the inlets, near-wall scaling, detecting and characterizing coherent structures in the flow as well as to provide data reduction strategies for comparison to CFD models (RANS and LES).

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With the growing interest in the issue of reducing powerconsumption in electricity applications, energy-saving devises and the problem of their operation gains more attention. The increase in the utilization of energy-saving lamps, especially LED lamps, leads to the wide interest in their influence on the power system. The impact of discussed devices on the voltage and current in the grid must be thoroughly studied before launching devices into the market. The studies undertaken on the LED lamps present in a wide range the issue of harmonic emission from lamps and their influence on power quality. Due to many anufacturing technologies, different LED devices can have various effects on the utility. It is significant to carry out researches concerning the adverse effects of energy-saving lamps in order to utilize devices that meet certain requirements which are set by the international commissions.

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Aim: To investigate how diversity within the African migrant population in Scotland affects their understandings of HIV and uptake of HIV testing and treatment, in order to improve HIV-related outcomes. Background: In the UK, Africans have the worst outcomes for HIV infection, primarily due to late diagnosis. Improvement requires better understanding of the barriers to healthcare engagement. This PhD study investigates how diversity among first generation African migrants in Scotland could affect engagement with general healthcare and HIV related interventions and services. Methods: I conducted qualitative research, involving participant observation at two sites (an African religious group and an asylum seeker/refugee drop-in centre) and interviews with African migrants attending these and three additional sites (two advocacy charities and a student association). Data were collected in two cities (Glasgow and Edinburgh) and two smaller towns (Paisley and Kirkcaldy). I interviewed 27 Africans, including economic migrants (n=8), students (n=9) and asylum seeker/refugees (n=10) and 14 representatives from organisations with high levels of African attendees (e.g., country associations, community organisations, advocacy groups, commercial establishments and religious based organisations). Thematic data analysis was carried out. Results: Diversity of the population and related issues of identity: Participants were highly diverse and reported considerable heterogeneity in the African diaspora in Scotland. The identity of “African” was bound with various negative stereotypes and appeals to this identity did not necessarily have relevance for participants. Nature of African affiliated organisations in Scotland: There were a wide range of organisations that advertised their remit as catering for the African diaspora. They varied in consistency and sustainability and contributed towards healthcare engagement to different degrees. Engagement with healthcare: There were multiple experiences and understandings of the healthcare system within the sample as a whole, and to an extent by migrant type. Whilst the majority reported successful and satisfactory service use, distinct barriers emerged. These included: understandings of rights and access to care based on African models of healthcare; the interplay of religious based understandings with ideas about access to healthcare; and assumptions and anxiety about the connections between visa status and health status. Knowledge of HIV and engagement with HIV related services: Participants had good knowledge about HIV, with some notable exceptions, but there was no patterning by migrant type. They had diverse views about risk of HIV infection, most of which did not align with the HIV epidemiology that identifies African migrants as an at risk group. Most of the sample did not think targeting African migrants for HIV interventions would be successful and were hostile to the proposal for various reasons, especially because they believed it would perpetuate stigma and prejudice towards the African diaspora. There were mixed experiences of HIV related services, and prompts to test for HIV had elicited a range of reactions, the majority negative. Conclusion: Diversity within the African diaspora in Scotland should be taken into account to improve the salience and relevance of future HIV interventions. Attitudes towards current HIV testing promotion suggest that a more cooperative approach could be taken with African communities to build on existing relationships of trust and understandings of HIV.

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In the context of this work we evaluated a multisensory, noninvasive prototype platform for shake flask cultivations by monitoring three basic parameters (pH, pO2 and biomass). The focus lies on the evaluation of the biomass sensor based on backward light scattering. The application spectrum was expanded to four new organisms in addition to E. coli K12 and S. cerevisiae [1]. It could be shown that the sensor is appropriate for a wide range of standard microorganisms, e.g., L. zeae, K. pastoris, A. niger and CHO-K1. The biomass sensor signal could successfully be correlated and calibrated with well-known measurement methods like OD600, cell dry weight (CDW) and cell concentration. Logarithmic and Bleasdale-Nelder derived functions were adequate for data fitting. Measurements at low cell concentrations proved to be critical in terms of a high signal to noise ratio, but the integration of a custom made light shade in the shake flask improved these measurements significantly. This sensor based measurement method has a high potential to initiate a new generation of online bioprocess monitoring. Metabolic studies will particularly benefit from the multisensory data acquisition. The sensor is already used in labscale experiments for shake flask cultivations.

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Os conceitos de qualidade e capital humano são amplamente conhecidos e a sua importância aceite por todos. A aplicação destes pressupostos à realidade do trabalho temporário, tomou-se um imperativo face ao contexto económico actual, repleto de rápidas mudanças organizacionais, caracterizado por colaboradores detentores de um novo leque de competências e flexibilidade profissional. Ao longo deste trabalho. procurou-se analisar a possível integração do trabalho temporário num novo modelo de relações laborais, na tentativa de distanciamento da corrente associação do trabalho temporário a uma "forma atípica de trabalho'', estabelecendo ainda uma breve evolução do trabalho temporário na Península de Setúbal. baseada na apreciação de trabalhos análogos. Em resultado da aplicação de questionário. definiu-se uma hierarquia de características individuais e organizacionais, como critério válido para um futuro processo de recrutamento e selecção, permitindo averiguar, ao nível do individuo, um aumento de competências profissionais e técnicas, acompanhado pelo incremento de formação e experiência profissional. Concluindo ao nível organizacional que qualidades como flexibilidade e dinamismo, aliado à experiência profissional, são factores críticos no processo de recrutamento e selecção, sendo imprescindíveis na procura contínua da qualidade, facilitando o alcance da excelência individual e organizacional. ABSTRACT: Quality and Human Capital are widely know concepts and their importance is accepted by all. Therefore, it has become imperative to make use of them in the contex t of temporary work given the current economic situation for they are present wherever organizational change happens rapidly and stakeholders possess a wide range of professional competencies and flexibility. The aim of this work is to study the possible integration of temporary work into a new model for labour relations, in an effort to distance temporay work from the notion of "atypical form of work" with which it is presently associated. Moreover, it presents a brief evolution of temporary work in the Peninsula of Setúbal, based on the analiysis of similar works. The findings obtained from our surveys ena bled us to define a hierarchy of individual and organizational characteristics which can serve as valid criteria in future recruitment and selection processes. With these processes it is al so possible to assess any increase of professional and technical competencies regarding the individual as well improvement as regards training and professional experience. At the organizational level, qualities such as nexibility and dynamism, together with professional experience, turned out to be critical factors in the recruitment and selection process. Not only are they indispensable in the constant pursuit of quality, but they also make it easy to achieve individual and organizational excellence.

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Natural language processing has achieved great success in a wide range of ap- plications, producing both commercial language services and open-source language tools. However, most methods take a static or batch approach, assuming that the model has all information it needs and makes a one-time prediction. In this disser- tation, we study dynamic problems where the input comes in a sequence instead of all at once, and the output must be produced while the input is arriving. In these problems, predictions are often made based only on partial information. We see this dynamic setting in many real-time, interactive applications. These problems usually involve a trade-off between the amount of input received (cost) and the quality of the output prediction (accuracy). Therefore, the evaluation considers both objectives (e.g., plotting a Pareto curve). Our goal is to develop a formal understanding of sequential prediction and decision-making problems in natural language processing and to propose efficient solutions. Toward this end, we present meta-algorithms that take an existent batch model and produce a dynamic model to handle sequential inputs and outputs. Webuild our framework upon theories of Markov Decision Process (MDP), which allows learning to trade off competing objectives in a principled way. The main machine learning techniques we use are from imitation learning and reinforcement learning, and we advance current techniques to tackle problems arising in our settings. We evaluate our algorithm on a variety of applications, including dependency parsing, machine translation, and question answering. We show that our approach achieves a better cost-accuracy trade-off than the batch approach and heuristic-based decision- making approaches. We first propose a general framework for cost-sensitive prediction, where dif- ferent parts of the input come at different costs. We formulate a decision-making process that selects pieces of the input sequentially, and the selection is adaptive to each instance. Our approach is evaluated on both standard classification tasks and a structured prediction task (dependency parsing). We show that it achieves similar prediction quality to methods that use all input, while inducing a much smaller cost. Next, we extend the framework to problems where the input is revealed incremen- tally in a fixed order. We study two applications: simultaneous machine translation and quiz bowl (incremental text classification). We discuss challenges in this set- ting and show that adding domain knowledge eases the decision-making problem. A central theme throughout the chapters is an MDP formulation of a challenging problem with sequential input/output and trade-off decisions, accompanied by a learning algorithm that solves the MDP.

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Nanopore-based sequencer will open the path to the fourth-generation DNA sequencing technology. The main differences between this technique and the previous ones are: DNA molecule that will be sequenced does not need a previous amplification step, is not necessary any type of specific label both molecular adaptors, and it has been abolished enzymatic process in the nucleotide sequence identification event. These differences have as result a more economic method since don’t spend the necessary reagents for the previous techniques, furthermore it lets to sequence samples with a low DNA concentration. This technique is based in the use of a membrane with a biologic nanopore inserted in it whereby the molecule to analyze (analyte) it made to pass, this membrane is placed between two reservoirs containing ions, when an external volatage is applied in both sides this lead to an ion current through the nanopore. When an analyte cross the nanopore the ion current is modified, that modification in the amplitude and duration of ion current determine the physical and chemical properties of that analyte. By means of subsequent statistical analyzes it can be determined to what sequence own this ion current blockade patterns. More used nanopores are the biologic ones, although they are working to develop synthetic nanopores. The main biologic nanopores are: α-Hemolysin from Staphylococcus aureus (α-HL), Mycobacterium smegmatis porin A (MspA) and bacteriophage phi29 pore (phi29). Α-HL and MspA have in their narrowest point a diameter similar to nucleotide size, they are functional at high temperature both wide range of pH (2-12) but MspA is able to read four nucleotide at the same time while α- HL just can read one by one. Finally, phi29 present a bigger diameter what let to get information about DNA spatial conformation and their interaction with proteins (Feng et al., 2015). Nowaday Oxford Nanopore Technologies (ONT) is the only company which has developed Nanopore technology; they have two devices available to sequencing (PromethION and MinION). The MinION is a single-use DNA sequencing device with the size of a USB memory with a total of 3000 nanopores that can sequence until 200kb. The PrometheION is big size sequencer that own 48 different cells, what let to sequence different samples at the same time, with a total of 144.000 nanopores and reading of several megabases (https://www.nanoporetech.com/). The high processivity and low cost become this technique in a great option to massive- sequencing.

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Many different photovoltaic technologies are being developed for large-scale solar energy conversion such as crystalline silicon solar cells, thin film solar cells based on a-Si:H, CIGS and CdTe. As the demand for photovoltaics rapidly increases, there is a pressing need for the identification of new visible light absorbing materials for thin-film solar cells. Nowadays there are a wide range of earth-abundant absorber materials that have been studied around the world by different research groups. The current thin film photovoltaic market is dominated by technologies based on the use of CdTe and CIGS, these solar cells have been made with laboratory efficiencies up to 19.6% and 20.8% respectively. However, the scarcity and high cost of In, Ga and Te can limit in the long-term the production in large scale of photovoltaic devices. On the other hand, quaternary CZTSSe which contain abundant and inexpensive elements like Cu, Zn, Sn, S and Se has been a potential candidate for PV technology having solar cell efficiency up to 12.6%, however, there are still some challenges that must be accomplished for this material. Therefore, it is evident the need to find the alternative inexpensive and earth abundant materials for thin film solar cells. One of these alternatives is copper antimony sulfide(CuSbS2) which contains abundant and non-toxic elements which has a direct optical band gap of 1.5 eV, the optimum value for an absorber material in solar cells, suggesting this material as one among the new photovoltaic materials. This thesis work focuses on the preparation and characterization of In6Se7, CuSbS2 and CuSb(S1-xSex)2 thin films for their application as absorber material in photovoltaic structures using two stage process by the combination of chemical bath deposition and thermal evaporation.

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Ionic liquids (ILs) have attracted great attention, from both industry and academia, as alternative fluids for very different types of applications. The large number of cations and anions allow a wide range of physical and chemical characteristics to be designed. However, the exhaustive measurement of all these systems is impractical, thus requiring the use of a predictive model for their study. In this work, the predictive capability of the conductor-like screening model for real solvents (COSMO-RS), a model based on unimolecular quantum chemistry calculations, was evaluated for the prediction water activity coefficient at infinite dilution, gamma(infinity)(w), in several classes of ILs. A critical evaluation of the experimental and predicted data using COSMO-RS was carried out. The global average relative deviation was found to be 27.2%, indicating that the model presents a satisfactory prediction ability to estimate gamma(infinity)(w) in a broad range of ILs. The results also showed that the basicity of the ILs anions plays an important role in their interaction with water, and it considerably determines the enthalpic behavior of the binary mixtures composed by Its and water. Concerning the cation effect, it is possible to state that generally gamma(infinity)(w) increases with the cation size, but it is shown that the cation-anion interaction strength is also important and is strongly correlated to the anion ability to interact with water. The results here reported are relevant in the understanding of ILs-water interactions and the impact of the various structural features of its on the gamma(infinity)(w) as these allow the development of guidelines for the choice of the most suitable lLs with enhanced interaction with water.

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Program comprehension requires developers to reason about many kinds of highly interconnected software entities. Dealing with this reality prompts developers to continuously intertwine searching and navigation. Nevertheless, most integrated development environments (IDEs) address searching by means of many disconnected search tools, making it difficult for developers to reuse search results produced by one search tool as input for another search tool. This forces developers to spend considerable time manually linking disconnected search results. To address this issue we propose Spotter, a model for expressing and combining search tools in a unified way. The current implementation shows that Spotter can unify a wide range of search tools. More information about Spotter can be found at scg.unibe.ch/research/moldablespotter

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We show that a wide-angle converging wave may be transformed into a shape-preserving accelerating beam having a beam-width near the diffraction limit. For that purpose, we followed a strategy that is particularly conceived for the acceleration of nonparaxial laser beams, in contrast to the well-known method by Siviloglou et al (2007 Phys. Rev. Lett. 99 213901). The concept of optical near-field shaping is applied to the design of non-flat ultra-narrow diffractive optical elements. The engineered curvilinear caustic can be set up by the beam emerging from a dynamic assembly of elementary gratings, the latter enabling to modify the effective refractive index of the metamaterial as it is arranged in controlled orientations. This light shaping process, besides being of theoretical interest, is expected to open up a wide range of broadband application possibilities.

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Time-REsolved Laser Induced Breakdown Spectroscopy (TRELIBS) was used to determine the elemental concentration of barium in Texas Dome rock salt. TRELIBS allows for an efficient and in situ concentration analysis technique that detects a wide range of elements with no sample preparation. TRELIBS measurements were made in the 545nm to 594nm wavelength range. The proximity of a strong barium emission line (553.5481 nm) to the sodium doublet (588.9950 nm and 589.5924 nm) allowed for measurement within a single frame of the spectrograph. This barium emission line was compared to the sodium doublet for relative intensity. A homemade calibration sample containing known amounts of barium and sodium was used to determine the relative concentrations. By approximating the sodium content in the rock salt as 50%, we determined the absolute concentration of barium in the salt to be (0.13±0.03)%.

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As users continually request additional functionality, software systems will continue to grow in their complexity, as well as in their susceptibility to failures. Particularly for sensitive systems requiring higher levels of reliability, faulty system modules may increase development and maintenance cost. Hence, identifying them early would support the development of reliable systems through improved scheduling and quality control. Research effort to predict software modules likely to contain faults, as a consequence, has been substantial. Although a wide range of fault prediction models have been proposed, we remain far from having reliable tools that can be widely applied to real industrial systems. For projects with known fault histories, numerous research studies show that statistical models can provide reasonable estimates at predicting faulty modules using software metrics. However, as context-specific metrics differ from project to project, the task of predicting across projects is difficult to achieve. Prediction models obtained from one project experience are ineffective in their ability to predict fault-prone modules when applied to other projects. Hence, taking full benefit of the existing work in software development community has been substantially limited. As a step towards solving this problem, in this dissertation we propose a fault prediction approach that exploits existing prediction models, adapting them to improve their ability to predict faulty system modules across different software projects.

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There is a growing societal need to address the increasing prevalence of behavioral health issues, such as obesity, alcohol or drug use, and general lack of treatment adherence for a variety of health problems. The statistics, worldwide and in the USA, are daunting. Excessive alcohol use is the third leading preventable cause of death in the United States (with 79,000 deaths annually), and is responsible for a wide range of health and social problems. On the positive side though, these behavioral health issues (and associated possible diseases) can often be prevented with relatively simple lifestyle changes, such as losing weight with a diet and/or physical exercise, or learning how to reduce alcohol consumption. Medicine has therefore started to move toward finding ways of preventively promoting wellness, rather than solely treating already established illness.^ Evidence-based patient-centered Brief Motivational Interviewing (BMI) interventions have been found particularly effective in helping people find intrinsic motivation to change problem behaviors after short counseling sessions, and to maintain healthy lifestyles over the long-term. Lack of locally available personnel well-trained in BMI, however, often limits access to successful interventions for people in need. To fill this accessibility gap, Computer-Based Interventions (CBIs) have started to emerge. Success of the CBIs, however, critically relies on insuring engagement and retention of CBI users so that they remain motivated to use these systems and come back to use them over the long term as necessary.^ Because of their text-only interfaces, current CBIs can therefore only express limited empathy and rapport, which are the most important factors of health interventions. Fortunately, in the last decade, computer science research has progressed in the design of simulated human characters with anthropomorphic communicative abilities. Virtual characters interact using humans’ innate communication modalities, such as facial expressions, body language, speech, and natural language understanding. By advancing research in Artificial Intelligence (AI), we can improve the ability of artificial agents to help us solve CBI problems.^ To facilitate successful communication and social interaction between artificial agents and human partners, it is essential that aspects of human social behavior, especially empathy and rapport, be considered when designing human-computer interfaces. Hence, the goal of the present dissertation is to provide a computational model of rapport to enhance an artificial agent’s social behavior, and to provide an experimental tool for the psychological theories shaping the model. Parts of this thesis were already published in [LYL+12, AYL12, AL13, ALYR13, LAYR13, YALR13, ALY14].^