77 resultados para Portos marítimos - São Luis (MA)
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Automated airborne collision-detection systems are a key enabling technology for facilitat- ing the integration of unmanned aerial vehicles (UAVs) into the national airspace. These safety-critical systems must be sensitive enough to provide timely warnings of genuine air- borne collision threats, but not so sensitive as to cause excessive false-alarms. Hence, an accurate characterisation of detection and false alarm sensitivity is essential for understand- ing performance trade-offs, and system designers can exploit this characterisation to help achieve a desired balance in system performance. In this paper we experimentally evaluate a sky-region, image based, aircraft collision detection system that is based on morphologi- cal and temporal processing techniques. (Note that the examined detection approaches are not suitable for the detection of potential collision threats against a ground clutter back- ground). A novel collection methodology for collecting realistic airborne collision-course target footage in both head-on and tail-chase engagement geometries is described. Under (hazy) blue sky conditions, our proposed system achieved detection ranges greater than 1540m in 3 flight test cases with no false alarm events in 14.14 hours of non-target data (under cloudy conditions, the system achieved detection ranges greater than 1170m in 4 flight test cases with no false alarm events in 6.63 hours of non-target data). Importantly, this paper is the first documented presentation of detection range versus false alarm curves generated from airborne target and non-target image data.
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Food has been a major agenda in political, socio-cultural, and environmental domains throughout history. The significance of food has been particularly highlighted in recent years with the growing public awareness of the unfolding impacts of climate change, challenging our understanding, practice, and expectations of our relationship with food. Parallel to this development has been the rise of web applications such as blogs, wikis, video and photo sharing sites, and social networking systems that are arguably more open, collaborative, and personalisable. These so-called Web 2.0 technologies have contributed to a more participatory Internet experience than what had previously been possible. An increasing number of these social applications are now available on mobile technologies where they take advantage of device-specific features such as sensors, location and context awareness, further expanding potential for the culture of participation and creativity. This international volume assembles a diverse collection of book chapters that contribute towards exploring and better understanding the opportunities and challenges provided by tools, interfaces, methods, and practices of social and mobile technology to enable engagement with people and creativity in the domain of food in contemporary society. It brings together an international group of academics and practitioners from a diverse range of disciplines such as computing and engineering, social sciences, digital media and human-computer interaction to critically examine a range of applications of social and mobile technology, such as social networking, mobile interaction, wikis, twitter, blogging, mapping, shared displays and urban screens, and their impact to foster a better understanding and practice of environmentally, socio-culturally, economically, and health-wise sustainable food culture.
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Preventive Maintenance (PM) is often applied to improve the reliability of production lines. A Split System Approach (SSA) based methodology is presented to assist in making optimal PM decisions for serial production lines. The methodology treats a production line as a complex series system with multiple (imperfect) PM actions over multiple intervals. The conditional and overall reliability of the entire production line over these multiple PM intervals are hierarchically calculated using SSA, and provide a foundation for cost analysis. Both risk-related cost and maintenance-related cost are factored into the methodology as either deterministic or random variables. This SSA based methodology enables Asset Management (AM) decisions to be optimised considering a variety of factors including failure probability, failure cost, maintenance cost, PM performance, and the type of PM strategy. The application of this new methodology and an evaluation of the effects of these factors on PM decisions are demonstrated using an example. The results of this work show that the performance of a PM strategy can be measured by its Total Expected Cost Index (TECI). The optimal PM interval is dependent on TECI, PM performance and types of PM strategies. These factors are interrelated. Generally, it was found that a trade-off between reliability and the number of PM actions needs to be made so that one can minimise Total Expected Cost (TEC) for asset maintenance.
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Background: Previous studies have found significant stressors experienced by nurses working in haemodialysis units yet renal nurses appear to report less burnout than other nurses. Objectives: This study aims to undertake an inductive process to better understand the stressors and the coping strategies used by renal nurses that may lead to resilience. Method: Sixteen haemodialysis nurses from a metropolitan Australian hospital and two satellite units participated in open-ended interviews. Data were analysed from a grounded theory methodology. Measures of burnout and resilience were also obtained. Results: Two major categories of stressors emerged. First, due to prolonged patient contact, family-like relationships developed that lead to the blurring of boundaries. Second, participants experienced discrimination from both patients and staff. Despite these stressors, the majority of participants reported low burnout and moderately high-to-high levels of resilience. The major coping strategy that appeared to promote resilience was emotional distancing, while emotional detachment appeared to promote burn-out. Conclusion: Assisting nurses to use emotional distancing, rather than emotional detachment strategies to engender a sense of personal achievement may promote resilience.
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900-word travel article about Iceland.
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This paper investigates learning environments from the view of the key users - students. Recent literature on designing Learning Landscapes indicates a near absence of the student voice, assuming that the majority of students are either uninterested or unable to express what they want or need, in a learning environment. The focus of this research is to reveal Architecture and Fashion Design students perceptions of their learning environments. Furthermore, this study questions the appropriateness of usual design of learning spaces for Design students, or if the environment needs to be specifically catered for the learning of different disciplines of Design, such as Architecture and Fashion Design. Senior Architecture and Fashion Design students were invited to participate in a qualitative mixed method study, including investigation into existing literature, questionnaires, focus groups and spontaneous participatory research. Through the analysis of data it was found that students perceptions validate discipline specific learning environments and contribute towards the development of a framework for the design of future Learning Landscapes, for Design education.
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A newly developed computational approach is proposed in the paper for the analysis of multiple crack problems based on the eigen crack opening displacement (COD) boundary integral equations. The eigen COD particularly refers to a crack in an infinite domain under fictitious traction acting on the crack surface. With the concept of eigen COD, the multiple cracks in great number can be solved by using the conventional displacement discontinuity boundary integral equations in an iterative fashion with a small size of system matrix to determine all the unknown CODs step by step. To deal with the interactions among cracks for multiple crack problems, all cracks in the problem are divided into two groups, namely the adjacent group and the far-field group, according to the distance to the current crack in consideration. The adjacent group contains cracks with relatively small distances but strong effects to the current crack, while the others, the cracks of far-field group are composed of those with relatively large distances. Correspondingly, the eigen COD of the current crack is computed in two parts. The first part is computed by using the fictitious tractions of adjacent cracks via the local Eshelby matrix derived from the traction boundary integral equations in discretized form, while the second part is computed by using those of far-field cracks so that the high computational efficiency can be achieved in the proposed approach. The numerical results of the proposed approach are compared not only with those using the dual boundary integral equations (D-BIE) and the BIE with numerical Green's functions (NGF) but also with those of the analytical solutions in literature. The effectiveness and the efficiency of the proposed approach is verified. Numerical examples are provided for the stress intensity factors of cracks, up to several thousands in number, in both the finite and infinite plates.
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Papagoite is a silicate mineral named after an American Indian tribe and was used as a healing mineral. Papagoite CaCuAlSi2O6(OH)3 is a hydroxy mixed anion compound with both silicate and hydroxyl anions in the formula. The structural characterization of the mineral papagoite remains incomplete. Papagoite is a four-membered ring silicate with Cu2+ in square planar coordination. The intense sharp Raman band at 1053 cm1 is assigned to the 1 (A 1g) symmetric stretching vibration of the SiO4 units. The splitting of the 3 vibrational mode offers support to the concept that the SiO4 tetrahedron in papagoite is strongly distorted. A very intense Raman band observed at 630 cm1 with a shoulder at 644 cm1 is assigned to the 4 vibrational modes. Intense Raman bands at 419 and 460 cm1 are attributed to the 2 bending modes. Intense Raman bands at 3545 and 3573 cm1 are assigned to the stretching vibrations of the OH units. Low-intensity Raman bands at 3368 and 3453 cm1 are assigned to water stretching modes. It is suggested that the formula of papagoite is more likely to be CaCuAlSi2O6(OH)3 xH2O. Hence, vibrational spectroscopy has been used to characterize the molecular structure of papagoite.
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Electronic word-of-mouth (eWOM) has gained significant attention from academics and practitioners since it has become an important source of consumers product information, which can influence consumer purchase intentions (Cheung & Lee, 2012). eWOM exchanges exist in two types of online communities: online communities of practice and online communities of interest. A few prior studies in online communities of interest have examined members motivations for product knowledge exchange (Hung & Li, 2007; Ma & Agarwal, 2007). However, there is a lack of understanding of member motivations for exchanging social bonds and enjoyment in addition to exchanging knowledge pertaining to products in the community. It is important to have an initial comprehension of motivation as an antecedent of these three eWOM exchanges so as to be able to determine the driving factors that lead members to generate eWOM communication. Thus, the research problem "What are the driving factors for members to exchange eWOM in an online community?" was justified for investigation. The purpose of this study was to examine different member motivations for exchanging three types of eWOM. Resource exchange theory and theory on consumer motivation and behavior were applied to develop a conceptual framework for this study. This study focused on an online beauty community since there is an increasing trend of consumers turning to online beauty resources so as to exchange useful beauty product information (SheSpot, 2011). As this study examined consumer motivation in an online beauty community, a web-based survey was the most effective and efficient way to gain responses from beauty community members and these members were appropriate samples from which to draw a conclusion about the whole population. Multiple regression analysis was used to test the relationships between member motivations and eWOM exchanges. It was found that members have different motivations for exchanging knowledge, social bonds, and enjoyment related to products: self-development, problem solving support, and relaxation, respectively. This study makes three theoretical contributions. First, this study identifies the influence of self-development motivation on knowledge exchange in an online community of interest, just as this motivation has previously been found in online communities of practice. This study highlights that members of the two different types of online communities share similar goals of knowledge exchange, despite the two communities evincing different attributes (e.g., member characteristics and tasks objectives). Further, this study will assist researchers to understand other motivations identified by prior research in online communities of practice since such motivations may be applicable to online communities of interest. Second, this study offers a new perspective on member motivation for social bonding. This study indicates that in addition to social support from friends and family, consumers are motivated to build social bonds with members in an online community of interest since they are an important source of problem solving support in regard to products. Finally, this study extends the body of knowledge pertaining to member motivation for enjoyment exchange. This study provides a basis for researchers to understand that members in an online community of interest value experiential aspects of enjoyable consumption activities, and thus based on group norms, members have a mutual desire for relaxation from enjoyment exchange. The major practical contribution is that this study provides an important guideline for marketing managers to develop different marketing strategies based on member motivations for exchanging three types of eWOM in an online community of interest, such as an online beauty community. This will potentially help marketing managers increase online traffic and revenue, and thus bring success to the community. Although, this study contributes to the literature by highlighting three distinctive member motivations for eWOM exchanges in an online community of interest, there are some possible research limitations. First, this study was conducted in an online beauty community in Australia. Hence, further research should replicate this study in other industries and nations so as to give the findings greater generalisability. Next, online beauty community members are female skewed. Thus, future research should examine whether similar patterns of motivations would emerge in other online communities that tend to be populated by males (e.g., communities focused on football). Further, a web-based survey has its limitations in terms of self-selection and self-reporting (Bhatnagar & Ghose, 2004). Therefore, further studies should test the framework by employing different research methods in order to overcome these weaknesses.
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A loss of function mutation in the TRESK K2P potassium channel (KCNK18), has recently been linked with typical familial migraine with aura. We now report the functional characterisation of additional TRESK channel missense variants identified in unrelated patients. Several variants either had no apparent functional effect, or they caused a reduction in channel activity. However, the C110R variant was found to cause a complete loss of TRESK function, yet is present in both sporadic migraine and control cohorts, and no variation in KCNK18 copy number was found. Thus despite the previously identified association between loss of TRESK channel activity and migraine in a large multigenerational pedigree, this finding indicates that a single non-functional TRESK variant is not alone sufficient to cause typical migraine and highlights the genetic complexity of this disorder. Migraine is a common, disabling neurological disorder with a genetic, environmental and in some cases hormonal component. It is characterized by attacks of severe, usually unilateral and throbbing headache, can be accompanied by nausea, vomiting and photophobia and is clinically divided into two main subtypes, migraine with aura (MA) when a migraine is accompanied by transient and reversible focal neurological symptoms and migraine without aura (MO)1. The multifactorial and clinical heterogeneity of the disorder have considerably hindered the identification of common migraine susceptibility genes and most of our current understanding comes from the studies of familial hemiplegic migraine (FHM), a rare monogenic autosomal dominant form of MA2. So far, the three susceptibility genes that have been convincingly identified in FHM families all encode ion channels or transporters: CACNA1A encoding the 1 subunit of the Cav2.1 calcium channel3, SCN1A encoding the Nav1.1 sodium channel4 and ATP1A2 encoding the 2 subunit of the Na+/K+ pump5. It is believed that mutations in these genes may lead to increased efflux of glutamate and potassium in the synapse and thereby cause migraine by rendering the brain more susceptible to cortical spreading depression (CSD)6 which is thought to play a role in initiating a migraine attack7,8. However, these genes have not to date been implicated in common forms of migraine9. Nevertheless, current opinion suggests that typical migraine, like FHM, is also disorder of neuronal excitability, ion homeostasis and neurotransmitter release10,11,12. Mutations in the SLC4A4 gene encoding the sodium-bicarbonate cotransporter NBCe1, have recently been implicated in several different forms of migraine13, and a variety of genes involved in glutamate homeostasis (PGCP, MTDH14 and LRP115) and a cation channel (TRPM8)15 have also recently been implicated in migraine via genome-wide association studies. Ion channels are therefore highly likely to play an important role in the pathogenesis of typical migraine. TRESK (KCNK18), is a member of the two-pore domain (K2P) family of potassium channels involved in the control of cellular electrical excitability16. Regulation of TRESK activity by the calcium-dependent phosphatase calcineurin17, as well as its expression in dorsal root ganglia (DRG)18 and trigeminal ganglia (TG)19,20 has led to a proposed role for this channel in a variety of pain pathways. In a recent study, a frameshift mutation (F139Wfsx24) in TRESK was identified in a large multigenerational pedigree where it co-segregated perfectly with typical MA and a significant genome-wide linkage LOD score of 3.0. Furthermore, functional analysis revealed that this mutation caused a complete loss of TRESK function and that the truncated subunit was also capable of down regulating wild-type channel function. This therefore highlighted KCNK18 as potentially important candidate gene and suggested that TRESK dysfunction might play a possible role in the pathogenesis of familial migraine with visual aura20. Additional screening for KCNK18 mutations in unrelated sporadic migraine and control cohorts also identified a number of other missense variants; R10G, A34V, C110R, S231P and A233V20. The A233V variant was found only in the control cohort, whilst A34V was identified in a single Australian migraine proband for which family samples were not available, but it was not detected in controls. By contrast, the R10G, C110R, and S231P variants were found in both migraineurs and controls in both cohorts. In this study, we have investigated the functional effect of these variants to further probe the potential association of TRESK dysfunction with typical migraine.
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Passenger flow studies in airport terminals have shown consistent statistical relationships between airport spatial layout and pedestrian movement, facilitating prediction of movement from terminal designs. However, these studies are done at an aggregate level and do not incorporate how individual passengers make decisions at a microscopic level. Therefore, they do not explain the formation of complex movement flows. In addition, existing models mostly focus on standard airport processing procedures such as immigration and security, but seldom consider discretionary activities of passengers, and thus are not able to truly describe the full range of passenger flows within airport terminals. As the route-choice decision-making of passengers involves many uncertain factors within the airport terminals, the mechanisms to fulfill the capacity of managing the route-choice have proven difficult to acquire and quantify. Could the study of cognitive factors of passengers (i.e. human mental preferences of deciding which on-airport facility to use) be useful to tackle these issues? Assuming the movement in virtual simulated environments can be analogous to movement in real environments, passenger behaviour dynamics can be similar to those generated in virtual experiments. Three levels of dynamics have been devised for motion control: the localised field, tactical level, and strategic level. A localised field refers to basic motion capabilities, such as walking speed, direction and avoidance of obstacles. The other two fields represent cognitive route-choice decision-making. This research views passenger flow problems via a "bottom-up approach", regarding individual passengers as independent intelligent agents who can behave autonomously and are able to interact with others and the ambient environment. In this regard, passenger flow formation becomes an emergent phenomenon of large numbers of passengers interacting with others. In the thesis, first, the passenger flow in airport terminals was investigated. Discretionary activities of passengers were integrated with standard processing procedures in the research. The localised field for passenger motion dynamics was constructed by a devised force-based model. Next, advanced traits of passengers (such as their desire to shop, their comfort with technology and their willingness to ask for assistance) were formulated to facilitate tactical route-choice decision-making. The traits consist of quantified measures of mental preferences of passengers when they travel through airport terminals. Each category of the traits indicates a decision which passengers may take. They were inferred through a Bayesian network model by analysing the probabilities based on currently available data. Route-choice decision-making was finalised by calculating corresponding utility results based on those probabilities observed. Three sorts of simulation outcomes were generated: namely, queuing length before checkpoints, average dwell time of passengers at service facilities, and instantaneous space utilisation. Queuing length reflects the number of passengers who are in a queue. Long queues no doubt cause significant delay in processing procedures. The dwell time of each passenger agent at the service facilities were recorded. The overall dwell time of passenger agents at typical facility areas were analysed so as to demonstrate portions of utilisation in the temporal aspect. For the spatial aspect, the number of passenger agents who were dwelling within specific terminal areas can be used to estimate service rates. All outcomes demonstrated specific results by typical simulated passenger flows. They directly reflect terminal capacity. The simulation results strongly suggest that integrating discretionary activities of passengers makes the passenger flows more intuitive, observing probabilities of mental preferences by inferring advanced traits make up an approach capable of carrying out tactical route-choice decision-making. On the whole, the research studied passenger flows in airport terminals by an agent-based model, which investigated individual characteristics of passengers and their impact on psychological route-choice decisions of passengers. Finally, intuitive passenger flows in airport terminals were able to be realised in simulation.
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Much is known about pedestrian behaviour and crash risk in developed countries. In contrast, the literature on pedestrian crash risk in developing countries reveals wide gaps in knowledge and understanding, and a comprehensive assessment is lacking. In particular, pedestrian behaviour in developing countries is fundamentally different in comparison to developed countries, and is influenced by a variety of less well understood contributing factors, leading to difficulty in modelling and predicting pedestrian crash risk and in turn identifying effective safety countermeasures. This paper provides a comprehensive synthesis of the factors known to influence pedestrian crash risk in developing countries, then focuses on Ethiopia as a specific example. The paper identifies where critical gaps in knowledge exist regarding pedestrian crash risk and associated behaviour in developing countries--a set of knowledge gaps which collectively are significant. The paper concludes by articulating a critical research path moving forward, with the aim to achieve an improved understanding of developing country pedestrian crash risk, and an ultimate goal of identifying effective pedestrian safety countermeasures suited to the unique challenges faced by transport system managers in developing countries.
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A key perspective on reputation is that of assessment. Much of the communication literature focuses on the influence organizations have on impression formation. This chapter however suggests that in order to understand reputation assessment, it is also important to understand the related concept of legitimacy. It addresses two approaches to understanding reputation namely accreditation and ranking. Accreditation alludes to concepts of legitimacy in which firms may acquire credibility by meeting formalized standards of certification. Ranking deals with categorizing and rating organizational reputations so that they may be assessed relative to one another. The chapter explores the various ways in which the mechanisms of accreditation and ranking operate and the role of social actors in developing and applying them. Ranking systems that provide the mechanism for comparing organizations and assessing their relative value are also explored.
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Objective To analyze the epidemiological trend of hepatitis B, liver cirrhosis and liver cancer during 1990 to 2007 in Shandong province, and to evaluate the effectiveness of hepatitis B prevention and control measures, so as to provide evidence for policy-making. Methods Based on the routine incidence data of hepatitis B, mortality data of hepatitis B, liver cirrhosis, liver cancer and demographic data, the incidence rate, mortality rate and age-specific mortality rate were calculated and analyzed with simple linear regression model. Results A total of 437094 cases of hepatitis B were reported during 1990 - 2007 with an average yearly morbidity of 27.32 per 100 000 persons and a decreased trend for the 0-9 years old children. At the same time, the adjusted mortality rate for hepatitis B and liver cirrhosis showed a decreased trend and the combined mortality rate decreased from 17.55 /100 000 in 1990 to 4.01 /100 000 in 2007. The mortality of liver cancer was stable during this time (P = 0. 9998). Conclusion Immunization of hepatitis B vaccine may have lowered the incidence of hepatitis B in the target population and the overall mortality rates of liver cirrhosis and liver cancer. Abstract in Chinese 19902007,,. ,3,. 19902007437 094,27.32/10,,09.,199017.55/1020074.01/10.(P=0.999 8). ,.
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Objectives In Aboriginal and Torres Strait Islander peoples in Queensland, to (a) determine the disease burden of common chronic lung diseases and (b) identify areas of need with respect to lung health services. Methods Literature reviews and analyses of hospitalisation and mortality data were used to describe disease epidemiology and available programs and services. Key stakeholder interviews and an online survey of health professionals were used to evaluate lung health services across the state and to identify services, needs and gaps. Results Morbidity and mortality from respiratory diseases in the Indigenous population is substantially higher than the non-Indigenous population across all age groups and regions. There are inadequate clinical services and resources to address disease prevention, detection, intervention and management in an evidence-based and culturally acceptable fashion. There is a lack of culturally appropriate educational resources and management programs, insufficient access to appropriately engaged Indigenous health professionals, a lack of multi-disciplinary specialist outreach teams, fragmented information systems and inadequate coordination of care. Conclusions Major initiatives are required at all levels of the healthcare system to adequately address service provision for Indigenous Queenslanders with lung diseases, including high quality research to investigate the causes for poor lung health, which are likely to be multifactorial.