958 resultados para coverage


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Climate-driven change represents the cumulative effect of global through local-scale conditions, and understanding their manifestation at local scales can empower local management. Change in the dominance of habitats is often the product of local nutrient pollution that occurs at relatively local scales (i.e. catchment scale), a critical scale of management at which global impacts will manifest. We tested whether forecasted global-scale change [elevated carbon dioxide (CO2) and subsequent ocean acidification] and local stressors (elevated nutrients) can combine to accelerate the expansion of filamentous turfs at the expense of calcifying algae (kelp understorey). Our results not only support this model of future change, but also highlight the synergistic effects of future CO2 and nutrient concentrations on the abundance of turfs. These results suggest that global and local stressors need to be assessed in meaningful combinations so that the anticipated effects of climate change do not create the false impression that, however complex, climate change will produce smaller effects than reality. These findings empower local managers because they show that policies of reducing local stressors (e.g. nutrient pollution) can reduce the effects of global stressors not under their governance (e.g. ocean acidification). The connection between research and government policy provides an example whereby knowledge (and decision making) across local through global scales provides solutions to some of the most vexing challenges for attaining social goals of sustainability, biological conservation and economic development.

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Les réseaux de capteurs sont formés d’un ensemble de dispositifs capables de prendre individuellement des mesures d’un environnement particulier et d’échanger de l’information afin d’obtenir une représentation de haut niveau sur les activités en cours dans la zone d’intérêt. Une telle détection distribuée, avec de nombreux appareils situés à proximité des phénomènes d’intérêt, est pertinente dans des domaines tels que la surveillance, l’agriculture, l’observation environnementale, la surveillance industrielle, etc. Nous proposons dans cette thèse plusieurs approches pour effectuer l’optimisation des opérations spatio-temporelles de ces dispositifs, en déterminant où les placer dans l’environnement et comment les contrôler au fil du temps afin de détecter les cibles mobiles d’intérêt. La première nouveauté consiste en un modèle de détection réaliste représentant la couverture d’un réseau de capteurs dans son environnement. Nous proposons pour cela un modèle 3D probabiliste de la capacité de détection d’un capteur sur ses abords. Ce modèle inègre également de l’information sur l’environnement grâce à l’évaluation de la visibilité selon le champ de vision. À partir de ce modèle de détection, l’optimisation spatiale est effectuée par la recherche du meilleur emplacement et l’orientation de chaque capteur du réseau. Pour ce faire, nous proposons un nouvel algorithme basé sur la descente du gradient qui a été favorablement comparée avec d’autres méthodes génériques d’optimisation «boites noires» sous l’aspect de la couverture du terrain, tout en étant plus efficace en terme de calculs. Une fois que les capteurs placés dans l’environnement, l’optimisation temporelle consiste à bien couvrir un groupe de cibles mobiles dans l’environnement. D’abord, on effectue la prédiction de la position future des cibles mobiles détectées par les capteurs. La prédiction se fait soit à l’aide de l’historique des autres cibles qui ont traversé le même environnement (prédiction à long terme), ou seulement en utilisant les déplacements précédents de la même cible (prédiction à court terme). Nous proposons de nouveaux algorithmes dans chaque catégorie qui performent mieux ou produits des résultats comparables par rapport aux méthodes existantes. Une fois que les futurs emplacements de cibles sont prédits, les paramètres des capteurs sont optimisés afin que les cibles soient correctement couvertes pendant un certain temps, selon les prédictions. À cet effet, nous proposons une méthode heuristique pour faire un contrôle de capteurs, qui se base sur les prévisions probabilistes de trajectoire des cibles et également sur la couverture probabiliste des capteurs des cibles. Et pour terminer, les méthodes d’optimisation spatiales et temporelles proposées ont été intégrées et appliquées avec succès, ce qui démontre une approche complète et efficace pour l’optimisation spatio-temporelle des réseaux de capteurs.

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This Master’s thesis examines the implementation of management system standard requirements as integrated in the organization. The aim is to determine how requirements from management system standards ISO 14001:2015 and ISO 9001:2015 can be integrated and implemented into the existing ISO 9001:2008 compliant management system. Research was executed as action research by utilizing an operating model about the integrated use of management system standards created by the International Organization for Standardization. Phases of the operating model were applied to the target organization. The similarity and integration potential of relevant standards were assessed by using comparative matrices. Allocation of the requirements and conformity assessment of the processes was executed by gap analysis. The main results indicate that the requirements of the relevant standards are principally equivalent or have the same kind of purpose. The results also show the most important processes of the target organization in terms of requirement compliance, as well as the requirements which affect the process the most. Prioritizing the compliance achievement of the most important processes and implementation of those requirements that have the most effect create an opportunity for organizations to implement the integrated requirements effectively.

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Immunization is the most cost-effective intervention for infectious diseases, which are the major cause of morbidity and mortality worldwide. Vaccines not only protect the individual who is vaccinated but also reduce the burden of infectious vaccine-preventable diseases for the entire community.1 Adult vaccination is very important given that >25% of mortality is due to infectious diseases.2 There is a scarcity of information on the vaccination status of young adults and the role of socioeconomic conditions in India.

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Atomic layer deposition (ALD) has been recognized as a promising method to deposit conformal and uniform thin film of copper for future electronic devices. However, many aspects of the reaction mechanism and the surface chemistry of copper ALD remain unclear. In this paper, we employ plane wave density functional theory (DFT) to study the transmetalation ALD reaction of copper dimethylamino-2-propoxide [Cu(dmap)2] and diethylzinc [Et2Zn] that was realized experimentally by Lee et al. [ Angew. Chem., Int. Ed. 2009, 48, 4536−4539]. We find that the Cu(dmap)2 molecule adsorbs and dissociates through the scission of one or two Cu–O bonds into surface-bound dmap and Cu(dmap) fragments during the copper pulse. As Et2Zn adsorbs on the surface covered with Cu(dmap) and dmap fragments, butane formation and desorption was found to be facilitated by the surrounding ligands, which leads to one reaction mechanism, while the migration of ethyl groups to the surface leads to another reaction mechanism. During both reaction mechanisms, ligand diffusion and reordering are generally endothermic processes, which may result in residual ligands blocking the surface sites at the end of the Et2Zn pulse, and in residual Zn being reduced and incorporated as an impurity. We also find that the nearby ligands play a cooperative role in lowering the activation energy for formation and desorption of byproducts, which explains the advantage of using organometallic precursors and reducing agents in Cu ALD. The ALD growth rate estimated for the mechanism is consistent with the experimental value of 0.2 Å/cycle. The proposed reaction mechanisms provide insight into ALD processes for copper and other transition metals.

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This index is designed to inform map users of the various series of maps produced and distributed by the U.S. Geological Survey, and to assist users in selecting and purchasing maps.

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Context. Recent observations of brown dwarf spectroscopic variability in the infrared infer the presence of patchy cloud cover. Aims. This paper proposes a mechanism for producing inhomogeneous cloud coverage due to the depletion of cloud particles through the Coulomb explosion of dust in atmospheric plasma regions. Charged dust grains Coulomb-explode when the electrostatic stress of the grain exceeds its mechanical tensile stress, which results in grains below a critical radius a < a Coul crit being broken up. Methods. This work outlines the criteria required for the Coulomb explosion of dust clouds in substellar atmospheres, the effect on the dust particle size distribution function, and the resulting radiative properties of the atmospheric regions. Results. Our results show that for an atmospheric plasma region with an electron temperature of Te = 10 eV (≈105 K), the critical grain radius varies from 10−7 to 10−4 cm, depending on the grains’ tensile strength. Higher critical radii up to 10−3 cm are attainable for higher electron temperatures. We find that the process produces a bimodal particle size distribution composed of stable nanoscale seed particles and dust particles with a ≥ a Coul crit , with the intervening particle sizes defining a region devoid of dust. As a result, the dust population is depleted, and the clouds become optically thin in the wavelength range 0.1–10 μm, with a characteristic peak that shifts to higher wavelengths as more sub-micrometer particles are destroyed. Conclusions. In an atmosphere populated with a distribution of plasma volumes, this will yield regions of contrasting radiative properties, thereby giving a source of inhomogeneous cloud coverage. The results presented here may also be relevant for dust in supernova remnants and protoplanetary disks.

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"Prepared by G. Joachim [i.e. Joachim G.] Elterich and Linda Graham"--Prelim. p.

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Background: Strategies to tackle maternal mortality in sub-Saharan Africa include expanding coverage of reproductive services.Even where high, more vulnerable women may not access services. No data is available on high coverage determinants. We investigated this in Tanzania in a predicted high utilization area. Methods: Data was collected through a household survey of 464 women with a recent delivery. Primary outcomes were facility delivery and ≥4 ANC visits. Determinants were analysed using multivariate regression. Results: Almost all women had attended ANC, though only 58.3% had ≥4 visits. ≥4 visits were more likely in the youngest age group (OR 2.7 95% CI 1.32–5.49, p=0.008), and in early ANC attenders (OR 3.2 95% CI 2.04–4.90, p<0.001). Facility delivery was greater than expected (87.7%), more likely in more educated women (OR 2.7 95% CI 1.50–4.75, p=0.002), in those within 5 kilometers of a facility (OR 3.2 95% CI 1.59–6.48, p=0.002), and for early ANC attenders (OR 2.4 95% CI 1.20–4.91, p=0.02). Conclusion: Rural contexts can achieve high facility delivery coverage. Based on our findings, strategies to reach women yet unserved should include promotion of early ANC start particularly for the less educated, and improvement of distant communities' access to facilities.

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A prepayment scheme for health through the National Health Insurance Scheme (NHIS) was commenced in Nigeria about ten years ago. Nigeria operates a federal system of government. Sub- national levels possess a high degree of autonomy in a number of sectors including health. It is important to assess the level of coverage of the scheme among the formal sector workers in Nigeria as a proxy to gauge the extent of coverage of the scheme and derive suitable lessons that could be used in its expansion. This is a cross-sectional, descriptive survey carried out among formal sector workers in Ilorin Kwara State, Nigeria. A stratified sampling technique was used to select study participants. A self-administered questionnaire was used to collect data from respondents. Data was analysed with the SPSS. Ethical approval to conduct the study was obtained from the Bowen University Teaching Hospital Research Ethics Committee. A total of 370 people participated in the study. Majority, (78.9%) of the respondents were aware of the NHIS, however only 13.5 % paid for health care services through the NHIS. Logistic regression analysis shows that respondents with post-secondary education (OR = 9.032, CI = 2.562 – 31.847, p = 0.001) and in federal civil service (OR = 2.679, CI = 1.036 – 6.929, p = 0.042) were over nine and three times more likely to be aware of the scheme than others. Coverage of the scheme among the respondents was unimpressive. A lot still need to be done to fast-track the expansion of the scheme among this sector of the population.

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Universal health coverage—defined as access to the full range of the most appropriate health care and technology for all people at the lowest possible price or with social health protection—was the goal of the 1978 Alma-Ata Conference on Primary Health Care in Kazakhstan. Many low-income (developing) countries are currently unable to reach this goal despite having articulated the same in their health-related documents. In this paper we argue that, over 30 years on, inadequate political and technical leadership has prevented the realization of universal health coverage in low-income countries.

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Universal health coverage—defined as access to the full range of the most appropriate health care and technology for all people at the lowest possible price or with social health protection—was the goal of the 1978 Alma-Ata Conference on Primary Health Care in Kazakhstan. Many low-income (developing) countries are currently unable to reach this goal despite having articulated the same in their health-related documents. In this paper we argue that, over 30 years on, inadequate political and technical leadership has prevented the realization of universal health coverage in low-income countries.