902 resultados para Area Under Curve


Relevância:

80.00% 80.00%

Publicador:

Resumo:

The notions of resolution and discrimination of probability forecasts are revisited. It is argued that the common concept underlying both resolution and discrimination is the dependence (in the sense of probability theory) of forecasts and observations. More specifically, a forecast has no resolution if and only if it has no discrimination if and only if forecast and observation are stochastically independent. A statistical tests for independence is thus also a test for no resolution and, at the same time, for no discrimination. The resolution term in the decomposition of the logarithmic scoring rule, and the area under the Receiver Operating Characteristic will be investigated in this light.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

This paper analyses the impacts of the 2003 CAP reform on the production of Italian olive oil controlling for the regional differences in olive oil production as well as for the differences between years. Italian olive oil production time series data from the Farm Accountancy Data Network for the 2000-2010 period at regional level is used to examine the effect of the 2003 Fischler reform on the production of olive oil. Production costs and payments received by farmers to support their income are considered. The data were collected at micro level based on a sample of farms representative of the production systems in the country. In order to consider the differences in production among the regions, eight representative regions in terms of surveyed farms are considered: Liguria, Toscana, Umbria, Lazio, Campania, Calabria, Puglia and Sicilia. We found that the most important factors affecting the production of olive oil are the area under olive groves and labour productivity. Results also show no evidence that the level of payments have an impact to the level of production, however, the type of payments has. Future work should explore the impact of the 2003 reform into the technical and production efficiency of the Italian olive oil farmers. It would be interesting to link the measures introduced by the cross compliance and the management practices of the different farms to have a more complete picture of the various parameters influencing the production of olive oil.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

The stratigraphic subdivision and correlation of dune deposits is difficult, especially when age datings are not available. A better understanding of the controls on texture and composition of eolian sands is necessary to interpret ancient eolian sediments. The Imbituba-Jaguaruna coastal zone (Southern Brazil, 28 degrees-29 degrees S) stands out due to its four well-preserved Late Pleistocene (eolian generation 1) to Holocene eolian units (eolian generations 2, 3, and 4). In this study, we evaluate the grain-size and heavy-mineral characteristics of the Imbituba-Jaguartma eolian units through statistical analysis of hundreds of sediment samples. Grain-size parameters and heavy-mineral content allow us to distinguish the Pleistocene from the Holocene units. The grain size displays a pattern of fining and better sorting from generation 1 (older) to 4 (younger), whereas the content of mechanically stable (dense and hard) heavy minerals decreases from eolian generation 1 to 4. The variation in grain size and heavy-mineral content records shifts in the origin and balance (input versus output) of eolian sediment supply attributable mainly to relative sea-level changes. Dunefields submitted to relative sea-level lowstand conditions (eolian generation 1) are characterized by lower accumulation rates and intense post-depositional dissection by fluvial incision. Low accumulation rates favor deflation in the eolian system, which promotes concentration of denser and stable heavy minerals (increase of ZTR index) as well as coarsening of eolian sands. Dissection involves the selective removal of finer sediments and less dense heavy minerals to the coastal source area. Under a high rate of relative sea-level rise and transgression (eolian generation 2), coastal erosion prevents deflation through high input of sediments to the coastal eolian source. This condition favors dunefield growth. Coastal erosion feeds sand from local sources to the eolian system. including sands from previous dunefields (eolian generation 1) and from drowned incised valleys. Therefore, dunefields corresponding to transgressive phases inherit the grain-size and heavy-mineral characteristics of previous dunefields, leading to selective enrichment of finer sands and lighter minerals. Eolian generations 3 and 4 developed during a regressive-progradational phase (Holocene relative sea level highstand). The high rate of sediment supply during the highstand phase prevents deflation. The lack of coastal erosion favors sediment supply from distal sources (fluvial sediments rich in unstable heavy minerals). Thus, dunefields of transgressive and highstand systems tracts may be distinguished from dunefields of the lowstand systems tract through high rates of accumulation (low deflation) in the former. The sediment source of the transgressive dunefields (high input of previously deposited coastal sands) differs from that of the highstand dunefields (high input of fluvial distal sands). Based on this case study, we propose a general framework for the relation between relative sea level, sediment supply and the texture and mineralogy of eolian sediments deposited in siliciclastic wet coastal zones similar to the Imbituba-Jaguaruna coast (C) 2009 Elsevier B.V. All rights reserved.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Objective: To define and evaluate a Computer-Vision (CV) method for scoring Paced Finger-Tapping (PFT) in Parkinson's disease (PD) using quantitative motion analysis of index-fingers and to compare the obtained scores to the UPDRS (Unified Parkinson's Disease Rating Scale) finger-taps (FT). Background: The naked-eye evaluation of PFT in clinical practice results in coarse resolution to determine PD status. Besides, sensor mechanisms for PFT evaluation may cause patients discomfort. In order to avoid cost and effort of applying wearable sensors, a CV system for non-invasive PFT evaluation is introduced. Methods: A database of 221 PFT videos from 6 PD patients was processed. The subjects were instructed to position their hands above their shoulders besides the face and tap the index-finger against the thumb consistently with speed. They were facing towards a pivoted camera during recording. The videos were rated by two clinicians between symptom levels 0-to-3 using UPDRS-FT. The CV method incorporates a motion analyzer and a face detector. The method detects the face of testee in each video-frame. The frame is split into two images from face-rectangle center. Two regions of interest are located in each image to detect index-finger motion of left and right hands respectively. The tracking of opening and closing phases of dominant hand index-finger produces a tapping time-series. This time-series is normalized by the face height. The normalization calibrates the amplitude in tapping signal which is affected by the varying distance between camera and subject (farther the camera, lesser the amplitude). A total of 15 features were classified using K-nearest neighbor (KNN) classifier to characterize the symptoms levels in UPDRS-FT. The target ratings provided by the raters were averaged. Results: A 10-fold cross validation in KNN classified 221 videos between 3 symptom levels with 75% accuracy. An area under the receiver operating characteristic curves of 82.6% supports feasibility of the obtained features to replicate clinical assessments. Conclusions: The system is able to track index-finger motion to estimate tapping symptoms in PD. It has certain advantages compared to other technologies (e.g. magnetic sensors, accelerometers etc.) for PFT evaluation to improve and automate the ratings

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Although the development of geographic information system (GIS) technology and digital data manipulation techniques has enabled practitioners in the geographical and geophysical sciences to make more efficient use of resource information, many of the methods used in forming spatial prediction models are still inherently based on traditional techniques of map stacking in which layers of data are combined under the guidance of a theoretical domain model. This paper describes a data-driven approach by which Artificial Neural Networks (ANNs) can be trained to represent a function characterising the probability that an instance of a discrete event, such as the presence of a mineral deposit or the sighting of an endangered animal species, will occur over some grid element of the spatial area under consideration. A case study describes the application of the technique to the task of mineral prospectivity mapping in the Castlemaine region of Victoria using a range of geological, geophysical and geochemical input variables. Comparison of the maps produced using neural networks with maps produced using a density estimation-based technique demonstrates that the maps can reliably be interpreted as representing probabilities. However, while the neural network model and the density estimation-based model yield similar results under an appropriate choice of values for the respective parameters, the neural network approach has several advantages, especially in high dimensional input spaces.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Recently, a family was denied the right to subdivide their four-hectare property on the outskirts of Melbourne, Victoria into nine residential allotments ranging in size from 4000 m2 to 6600 m2. Unsuccessful applications and approaches in the past, prior to our commissioning in late 2003, had been rejected on the basis of assessments of poor land capability, onerous wet weather storage requirements and a curious 60 m buffer from a nearby intermittent watercourse. Restriction on the type of interim wastewater systems deemed suitable for five allotments was also a major issue. The site did not have mains power and had no sewer connections. The water authority and Victorian Civil and Administrative Tribunal (V CAT) order, prior to commissioning of the authors, asserted that "reticulated sewer is the preferred infrastructure for the area under investigation". However, the requirements imposed followed the letter of the guidelines rather than the principles. Various professional reports had already been produced on behalf of both the client and the regulator. A review of these indicated that the project had not been assessed in accordance with standard practices, had unusually restrictive assumptions, and did not accord with government policies on ecologically sustainable development.
The paper highlights the importance of sustaining professional and ethical practices to avoid costly litigation. Some professionals may have been in breach of the Institution of Engineers' Code of Ethics; others may have been in need of professional development. The question also arises whether the regulator had sought to use these adverse reports in order to satisfy unrelated planning issues.
While the writers managed to succeed in convincing the VCAT that these restrictions were unnecessary, the client ultimately had to comply with the regulator's wishes because of financial pressures. This unnecessary regimentation raises the issue of how best to safeguard lay people of moderate means against the practices of professional people who know or should know better.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

The high infant mortality in Zambia is largely attributable to malnutrition. It is exacerbated by the inability of mothers to recognise threats to nutritional status and take corrective action. Advice in ‘Health Centres’ is often inaccessible to mothers. The Traditional Birth Attendants (TBAs) work with pregnant women in local communities, and the purpose of this study was to develop and implement an educationprogram in growth monitoring and nutrition for the TBAs and then to evaluate its effects. Twenty five TBAs from two peri-urban areas of Kitwe were enrolled in this pilot study and eighteen completed the program. The researcher developed and taught a program to the TBAs over ten days. A pretest was given before the teaching program to enable the researcher to obtain information about the knowledge and skills of the TBAs. Following the teaching program the TBAs were re-tested, with the same questionnaire. Focus groups were conducted to enable the TBA to provide information on the teaching materials and the education program. The TBAs then returned to their communities and put into practice the skills and knowledge they had learned for six months. Their practice was monitored by a trained Public Health Nurse. The researcher also surveyed 38 pregnant women about their knowledge of growth monitoring and nutrition before the TBAs went into the field to work with their local communities. The same questionnaire used with the pregnant women was administered to 38 new mothers with children aged 0 to 6 months to gain information of their knowledge and skills following the work of the TBAs. The program was evaluated by assessing the extent to which TBAs knowledge and skills were increased, the knowledge and understanding of a selection of their clients and the rates of malnutrition of infants in the area under study. The results from the research clearly indicated that the teaching program on growth monitoring and nutrition given to the selected group of TBAs had a positive effect on their knowledge and skills. It was found that the teaching developed their knowledge, practical skills, evaluative skills. That they were able to give infants’ mothers sound advice regarding their children’s nutrition was revealed by the mother’s increased knowledge and the decrease in numbers of malnourished children in the study areas at the conclusion of the research. The major outcomes from the study are: that Zambian TBAs can be taught to carry out an expanded role; field experience is a key factor in the teaching program; making advice available in local communities is important; and preliminary data on the Zambian experience were generated. Recommendations are: The pilot program should be expanded with continuing support from the Health Department. Similar educational programs should be introduced into other areas of Zambia with support from the Ministry of Health. That in administering a teaching program: Sufficient time must be allocated to practical work to allow poorly educated women to attain the basic skills needed to master the complex skills required to competently reduce faltering in their communities. The teaching materials to illustrate nutritional principles for feeding programs must be developed to suite locally available foods and conditions. Methods of teaching should suit the local area, for example, using what facilities are locally available. The timing of the teaching program should be suitable for the TBAs to attend. This may vary from area to area, for example it may be necessary to avoid times traditionally given to fetching water or working in the fields. For similar reasons, the venue for the teaching program should be suitable to the TBAs. The teachers should go into the TBAs’ community rather than causing disruption of the TBAs’ day by expecting them to go to the teacher. Data should be collected from a larger group of TBAs and clients to enable sophisticated statistical analysis to complement data from this pilot program. The TBAs should be given recognition for their work and achievement. This is something which they asked for. They do not ask for payment, rather acknowledgment through regular follow up and approbation.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

OBJECTIVE--Observational studies show breaking up prolonged sitting has beneficial associations with cardiometabolic risk markers, but intervention studies are required to investigate causality. We examined the acute effects on postprandial glucose and insulin levels of uninterrupted sitting compared with sitting interrupted by brief bouts of light- or moderate-intensity walking.

RESEARCH DESIGN AND METHODS--
Overweight/obese adults (n = 19), aged 45-65 years, were recruited for a randomized three-period, three-treatment acute crossover trial: I) uninterrupted sitting; 2) seated with 2-min bouts of light-intensity walking every 20 rain; and 3) seated with 2-min bouts of moderate-intensity walking every 20 min. A standardized test drink was provided after an initial 2-h period of uninterrupted sitting. The positive incremental area under curves (iAUC) for glucose and insulin (mean [95% CI]) for the 5 h after the test drink (75 g glucose, 50 g fat) were calculated for the respective treatments.

RESULTS--The glucose iAUC (mmol/L) x h after both activity-break conditions was reduced (light: 5.2 [4.1-6.6]; moderate: 4.9 [3.8-6.1]; both P < 0.01) compared with uninterrupted sitting (6.9 [5.5-8.7]). Insulin iAUC (pmol/L) x h was also reduced with both activity-break conditions (light: 633.6 [552.4-727.1]; moderate: 637.6 [555.5-731.9], P < 0.0001) compared with uninterrupted sitting (828.6 [722.0-950.9]).

CONCLUSIONS--Interrupting sitting time with short bouts of light- or moderate-intensity walking lowers postprandial glucose and insulin levels in overweight/obese adults. This may improve glucose metabolism and potentially be an important public health and clinical intervention strategy for reducing cardiovascular risk.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Seafloors of unconsolidated sediment are highly dynamic features; eroding or accumulating under the action of tides, waves and currents. Assessing which areas of the seafloor experienced change and measuring the corresponding volumes involved provide insights into these important active sedimentation processes. Computing the difference between Digital Elevation Models (DEMs) obtained from repeat Multibeam Echosounders (MBES) surveys has become a common technique to identify these areas, but the uncertainty in these datasets considerably affects the estimation of the volumes displaced. The two main techniques used to take into account uncertainty in volume estimations are the limitation of calculations to areas experiencing a change in depth beyond a chosen threshold, and the computation of volumetric confidence intervals. However, these techniques are still in their infancy and, as a result, are often crude, seldom used or poorly understood. In this article, we explored a number of possible methodological advances to address this issue, including: (1) using the uncertainty information provided by the MBES data processing algorithm CUBE, (2) adapting fluvial geomorphology techniques for volume calculations using spatially variable thresholds and (3) volumetric histograms. The nearshore seabed off Warrnambool harbour - located in the highly energetic southwest Victorian coast, Australia - was used as a test site. Four consecutive MBES surveys were carried out over a four-months period. The difference between consecutive DEMs revealed an area near the beach experiencing large sediment transfers - mostly erosion - and an area of reef experiencing increasing deposition from the advance of a nearby sediment sheet. The volumes of sediment displaced in these two areas were calculated using the techniques described above, both traditionally and using the suggested improvements. We compared the results and discussed the applicability of the new methodological improvements. We found that the spatially variable uncertainty derived from the CUBE algorithm provided the best results (i.e. smaller confidence intervals), but that similar results can be obtained using as a fixed uncertainty value derived from a reference area under a number of operational conditions.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Este trabalho é fruto de uma investigação que buscou elucidar a relação estabelecida entre os serviços de saúde e os seus usuários. Com esse objetivo, utilizou-se uma abordagem antropológica que teve como referência a experiência empírica ligada à Unidade Conceição do Serviço de Saúde Comunitária do Grupo Hospitalar Conceição, em Porto Alegre, RS. Funcionando nas dependências do Hospital Nossa Senhora Conceição, a Unidade Conceição é um posto de saúde vinculado ao Sistema Único de Saúde (SUS) em que médicos gerais comunitários e outros profissionais vêm prestando atendimento de saúde, há cerca de 15 anos, aos moradores da sua vizinhança, calculados atualmente em mais de 20 mil pessoas. Tendo como pano de fundo as influências da cultura no comportamento humano e na prestação de atendimento de saúde, os desdobramentos principais da relação entre a Unidade e os seus usuários foram analisados sob diversos eixos: a história da Unidade, seus conflitos com a instituição e outras especialidades médicas; a relação da Unidade com a área geográfica sob sua responsabilidade; a questão da participação popular nos serviços de saúde, mais especificamente a experiência do seu Conselho Gestor Local; e, por fim, a avaliação dos serviços de saúde, principalmente no que concerne à perspectiva dos pacientes. Sempre que possível, a análise feita procurou fazer uma ligação com as mudanças ocorridas no sistema de saúde brasileiro nos últimos anos. Resgatar os aspectos culturais como elemento essencial para o estabelecimento de uma comunicação efetiva entre os indivíduos e os serviços formais de saúde mostrou-se fundamental para permitir o aprofundamento desse tipo de análise e para qualificar as ações desenvolvidas pelos serviços de saúde.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Este trabalho examina a lateralização cerebral de funções e sua implicação para a cognição humana ao nível da intersecção entre a neuropsicologia clinica e a psicologia cognitiva de base informacional. A primeira parte do trabalho e dedicada a descrição e análise critica da conformação contemporânea desta área de investigação neuropsicológica, com a ênfase posta na metateoria e teorias predominantes, a par do sistema conceitual utilizado nas atividades de pesquisa desenvolvidas na área. Inicialmente, a abordagem neuropsicológica do problema da lateralização cerebral examinada no que concerne às suas articulações com os métodos e técnicas que se mostraram mais importantes para a configuração atual desta área de investigação, sob um enfoque histórico. Em continuidade, a análise dirigida às questões mais fundamentais nas quais se tem desdobrado o problema da assimetria funcional inter-hemisférica, representadas pelas especializações funcionais dos hemisférios cerebrais, pela atividade conjunta dos hemisférios e pelas relações entre diferenças individuais na lateralização cerebral e desempenho cognitivo. Neste contexto são sublinhadas as dificuldades e inconsistências relacionadas à restritividade do enfoque prevalente, avaliado como expressão de uma concepção neuropsicológica excessivamente simplificadora do problema compreendido pelas relações entre o cérebro e a cognição humanos. O trabalho apresenta, em sua segunda parte, uma tentativa de desenvolvimento de um enfoque sistêmico, na direção da complexidade, para o problema da lateralização cerebral de funções. Trata-se de um desenvolvimento que parte de uma descentração da dimensão lateral do sistema nervoso e resulta em uma subsunção deste problema à uma perspectiva mais global concernente à organização cerebral de funções e aos fundamentos para a construção teórica na neuropsicologia. Segue-se um exame das implicações deste enfoque para a questão das relações entre variações inter-individuais na lateralização cerebral de funções e habilidades cognitivas que se direciona para uma minimização do significado que tem sido atribuído a lateralizarão para o funcionamento cerebral e a cognição humanos. O trabalho apresenta, finalmente, um estudo empírico referente às relações entre variações inter-individuais normais de lateralizarão cerebral ,preferência manipulatória e sua história familiar e desempenho cognitivo, onde são comparados os desempenhos de destros com história familiar de sinistralidade negativa e de canhotos com esta história positiva no Teste WAIS. Os resultados obtidos mostram uma inequívoca semelhança nos desempenhos dos dois grupos em todas as escalas do WAIS. Estes resultados são discutidos principalmente no que tange à existência ou não de correspondências diretas entre variações normais nas representações das funções ao longo da dimensão lateral do sistema nervoso, preferência manipulatória e habilidades cognitivas. A conclusão final conforma-se como um sumário integrativo dos principais aspectos das conclusões atingidas no curso do trabalho.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

This work analyses a study on natural ventilation and its relation to the urban legislation versus the building types in an urban fraction of coastal area of Praia do Meio in the city of Natal/RN, approaching the type or types of land use most appropriate to this limited urban fraction. The objective of this study is to analyse the effects of the present legislation as well as the types of buildings in this area on the natural ventilation. This urban fraction was selected because it is one of the sites from where the wind flows into the city of Natal. This research is based on the hypothesis stating that the reduction on the porosity of the urban soil (decrease in the set back/boundary clearance), and an increase in the form (height of the buildings) rise the level of the ventilation gradient, consequently causing a reduction on the wind speed at the lowest part of the buildings. Three-dimensional computational models were used to produce the modes of occupation allowed in the urban fraction within the area under study. A Computational Fluid Dynamics (CFD) software was also used to analyse the modes of land occupation. Following simulation, a statistical assessment was carried out for validation of the hypothesis. It was concluded that the reduction in the soil porosity as a consequence of the rates that defined the minimum boundary clearance between the building and the boundary of the plot (and consequently the set back), as well as the increase in the building form (height of the buildings) caused a reduction in the wind speed, thus creating heat islands

Relevância:

80.00% 80.00%

Publicador:

Resumo:

This study was intended to investigate how the urban form has been influencing the changes in the climate of the city and make a correlation between the climate and the thermal sensation of the users of open spaces. The research was developed in the district of Petrópolis in Natal/ RN whose occupation has been almost consolidated. Among other reasons, this district was selected because it was planned considering the environmental aspects of comfort. The methodologies used are based on KATZSCHNER (1997) and OLIVEIRA (1988) studies, which suggest the drawing and analysis of maps of the area under study, including topography, height of the buildings, land use, green areas, and types of soil pavement, as well as measurement of the environmental variables: air temperature, relative humidity, direction and wind speed for a comparative study. As part of this, study local users of the district were interviewed about their thermal sensations in open spaces. For the statistical analysis, data was collected at 10 distinct points characterized by BUSTOS ROMERO (2002), being 8 within the district and 2 at different places (outside the district), at climatologic stations, in 3 periods (August/2000, January/2002 and June/2002), for 4 consecutive days for each measurement (from Sunday to Wednesday) at the time of lower and higher temperatures in the city, 6:00 am and 1:00 pm, respectively. At the same time interviews were carried out with users of the open spaces in the area, totaling 171 valid formularies. The urban form showed a rather leveled topography, great diversity of land use and height of the buildings, with the existence of an area mostly occupied with high buildings, very little green area and soil practically impermeable. The statistical analysis showed high temperature and humidity levels. The wind direction is predominantly Southeast with extremely variable speeds. When the data from this district is compared with the data from other areas in the city and its outskirt, it was observed that this district is hotter and less ventilated than the others; besides, most users said that they felt uncomfortable in the local environmental conditions. The results of the analysis generated a zoning for the district with recommendations for soil occupation. The profile of the user was defined regarding the thermal comfort, as well as some discussion about the comfort parameters, including the proposal of limiting areas of temperature and humidity for the thermal comfort in the open spaces

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Relevância:

80.00% 80.00%

Publicador:

Resumo:

In this study a population survey of Carabidae and Staphylinidae (Coleoptera) adults was carried out with the aim to analyze their populations through faunistic indexes and to determine the influence of temperature, relative humidity and rainfall. The study was conducted in two areas cultivated with soybean/corn under no-tillage and conventional tillage systems and adjacent to a forest fragment and a Pinus stand, respectively. Beetles were sampled by pitfall traps distributed in two 100-m transects. The fauna was characterized by diversity (H), evenness (J), abundance, dominance, frequency and constancy indexes. The influence of air temperature, relative humidity and rainfall was verified using stepwise regression. The carabids Abaris basistriatus Chaudoir, Odontochila nodicornis (Dejean) and Scarites sp. were classified as predominant species in both areas, while Selenophorus alternans Dejean only classified as predominant in the area under conventional tillage system, likewise for Megacephala sp. and Selenophorus seriatoporus Putz. in the no-tillage area. The predominant species showed just one population peak each year, usually observed from December to January. The pluvial precipitation influenced the occurrence of the carabids positively and significantly, with O. nodicornis and Megacephala sp. being the most demanding species in relation to the effect of humidity on their dispersal.