Showing papers in "Scopus in 2016"

Recursive ground truth estimator for social data streams

Abstract: The paper develops a recursive state estimator for social network data streams that allows exploitation of social networks, such as Twitter, as sensor networks to reliably observe physical events. Recent literature suggested using social networks as sensor networks leveraging the fact that much of the information upload on the former constitutes acts of sensing. A significant challenge identified in that context was that source reliability is often unknown, leading to uncertainty regarding the veracity of reported observations. Multiple truth finding systems were developed to solve this problem, generally geared towards batch analysis of offline datasets. This work complements the present batch approaches by developing an online recursive state estimator that recovers ground truth from streaming data. In this paper, we model physical world state by a set of binary signals (propositions, called assertions, about world state) and the social network as a noisy medium, where distortion, fabrication, omissions, and duplication are introduced. Our recursive state estimator is designed to recover the original binary signal (the true propositions) from the received noisy signal, essentially decoding the unreliable social network output to obtain the best estimate of ground truth in the physical world. Results show that the estimator is both effective and efficient at recovering the original signal with a high degree of accuracy. The estimator gives rise to a novel situation awareness tool that can be used for reliably following unfolding events in real time, using dynamically arriving social network data.

Mercury removal in wastewater by iron oxide nanoparticles

Abstract: Mercury is one of the persistent pollutants in wastewater; it is becoming a severe environmental and public health problem, this is why nowadays its removal is an obligation. Iron oxide nanoparticles are receiving much attention due to their properties, such as: great biocompatibility, ease of separation, high relation of surface-area to volume, surface modifiability, reusability, excellent magnetic properties and relative low cost. In this experiment, Fe3O4 and γ-Fe2O3 nanoparticles were synthesized using iron salts and NaOH as precipitation agents, and Aloe Vera as stabilizing agent; then these nanoparticles were characterized by three different measurements: first, using a Zetasizer Nano ZS for their size estimation, secondly UV-visible spectroscopy which showed the existence of resonance of plasmon at λmax~360 nm, and lastly by Scanning Electron Microscopy (SEM) to determine nanoparticles form. The results of this characterization showed that the obtained Iron oxides nanoparticles have a narrow size distribution (~100nm). Mercury removal of 70% approximately was confirmed by atomic absorption spectroscopy measurements.

Motivação, satisfação profissional e evasão no serviço público: o caso da carreira de especialistas em Políticas Públicas e Gestão Governamental

Abstract: Que fatores motivacionais afetam a retencao e a satisfacao de servidores publicos? A questao e relevante para a administracao publica brasileira, pois problemas de evasao e insatisfacao profissional tem sido observados em varias carreiras publicas no pais. Ao analisar a carreira dos especialistas em Politicas Publicas e Gestao Governamental (EPPGG), o artigo contribui a literatura sobre motivacao no servico publico, que enfatiza a importância dos fatores motivacionais intrinsecos. A analise mostra que: i) a evasao relaciona-se a fatores extrinsecos, ligados a remuneracao, enquanto ii) a satisfacao relaciona-se nao apenas a fatores extrinsecos, mas principalmente a fatores intrinsecos e simbolicos, ligados a natureza do trabalho. A contribuicao a agenda de pesquisas reforca a importância de se considerar logicas institucionais e aspectos culturais das carreiras publicas em estrategias para investigar as dinâmicas motivacionais que afetam as decisoes profissionais dos servidores.

Energy-efficient resource allocation with qos support in wireless body area networks

Abstract: Wireless Body Area Network (WBAN) has become a promising type of networks to provide applications such as real-time health monitoring and ubiquitous e-Health services. One challenge in the design of WBAN is that energy efficiency needs to be ensured to increase the network lifetime in such a resourceconstrained network. Another critical challenge for WBAN is that quality of service (QoS) requirements, including packet loss rate (PLR), throughput and delay, should be guaranteed even under the highly dynamic environment due to changing of body postures. In this paper, we design a unified framework of energy efficient resource allocation scheme for WBAN, in which both constraints of QoS metrics and the characteristics of dynamic links are considered. A transmission rate allocation policy (TRAP) is proposed to carefully adjust the transmission rate at each sensor such that more strict PLR requirement could be achieved even when the link quality is very poor. A QoS optimization problem is then formulated to optimize the transmission power and allocated time slots for each sensor, which minimizes energy consumption subject to the QoS constraints. Numerical results demonstrate the effectiveness of the proposed transmission rate allocation policy and the resource allocation scheme.

Robust, cost-effective and scalable localization in large indoor areas

Abstract: Indoor location information plays a fundamental role in supporting various interesting location- aware indoor applications. Widely deployed WiFi networks make it feasible to perform indoor localization by first establishing a received signal strength (RSS) map covering the whole area based on a signal propagation model, then determining a location from an online RSS measurement given the RSS map. However, challenges remain in practical deployments, due to inaccurately estimated RSS values in the RSS map and insufficient number of access points (APs) in large indoor areas. To address these challenges, we develop a robust, cost-effective and scalable localization system (REAL). Our approach takes the error from the indoor radio signal propagation model into consideration. It also exploits information of unobserved APs at a given location and an optimal clustering method in the location searching phase. Our real-world experimental results demonstrate that REAL achieves considerable localization accuracy at a very low training cost even for a large indoor area. In addition, the results show that our scheme can also be effectively applied to Bluetooth networks with sparse signal coverage.

Determination of the adaptability and stability of soybean cultivars in different locations and at different sowing times in Paraná state using the AMMI and Eberhart and Russel methods

Abstract: This study aimed to evaluate the adaptability and phenotypic stability of 10 soybean genotypes in 12 environments in Parana state by using the additive main effects and multiplicative interaction analysis (AMMI) and Eberhart and Russell models. The assays were conducted in a randomized complete block design with three replicates, in the 2010/2011 season in four locations in Parana state (Assai, Sao Pedro do Ivai, Cornelio Procopio, and Marilândia do Sul), and with three sowing dates (15/-20/10/10; 29/10-03/11/10; 15/-20/11/10). The cultivars tested with Roundup Ready® technology included SYN 1049, SYN 1152, SYN 1059, SYN 3358, SYN 1163, SYN 1157, V-MAX, FT Campo Mourao, BMX Potencia, and SYN 9070. The yield character was analyzed. Data were submitted to analysis of variance and the adaptability and stability were then analyzed. The results of the AMMI and Eberhart and Russell models were somewhat consistent for the stability parameter only. The AMMI analysis was able to capture 66% of the variance associated with residue no additives, of which 43.18% was retained in the first principal component of interaction and 23.58%, in the second component. This is sufficient to explain the genotype × environment interaction. The SYN 1059, SYN 1163, and VMAX genotypes are distinguished by their considerably higher yield and productive adaptation. In the AMMI analysis, the cultivar SYN 1163 showed commercial promise among the other cultivars for high grain yield performance, adaptation, and response predictability.

Mode selective coupler based in a dual-core photonic crystal fiber with non-identical cores for spatial mode conversion

Abstract: In this work, we present a mode selective converter based in a dual core photonic crystal fiber with non-identical cores. Mode conversion between the LP01 and LP11 modes is obtained and the operating wavelength can be continuously tuned by varying the refractive index of the liquid in the holes.

Characterization of photodectors using a monochromator and a broadband light source in the XYZ color space

Abstract: Photodetectors are sensors, which respond to the electromagnetic radiation of the spectrum. Their spectral response depends on many factors of the manufacturing process, e.g. the type of diode that is used or, in some cases, the optical elements that are added to limit the response band. In this paper, we propose an experimental methodology to obtain the spectral response of a photodetector by constructing the characteristic curve using the monochromatic response. For this purpose, we use a broadband source as input of the monochromator to vary the wavelength each five nm. The characteristic curves of one commercial color sensor were obtained (including the loss) using the output ratio of the monochromator. Via the numerical expression of the response curve, it is possible to model the actual response of the photodetectors to known or simulated spectra of electromagnetic radiation, and thus to generalize photometric measurements. Previously we have demonstrated the importance of obtaining such measurements to study light sources. Finally, this newly developed method helps studying the behavior of a photodetector in detail; hence, it enables the derivation of photometric measurements from known data or simulations.

Physicochemical and sensorial quality of banana genotypes

Abstract: Despite the diversity of banana varieties in Brazil, only a few cultivars have the proper agronomic traits and fruit quality for commercial exploitation. This study aimed at evaluating the physicochemical traits and sensorial acceptance of banana genotypes, in order to identify those with potential for commercial growing. Six improved banana genotypes were assessed (BRS Maravilha, PC 0101, FHIA 18, TM 2803, YB 4203 and BRS Caipira), as well as three commercial cultivars (Grand Naine, Pacovan and Prata Ana). Analyses of peel and pulp color, peel thickness, pulp yield, moisture, pH, soluble solids, titratable acidity, total carotenoids and sensorial acceptance were performed. The BRS Maravilha, FHIA 18, YB 4203 and BRS Caipira genotypes presented physicochemical traits similar to the Grand Naine, Pacovan and Prata Ana commercial cultivars. The BRS Maravilha and TM 2803 genotypes had sensorial acceptance similar to the Prata Ana and Grand Naine cultivars, and are therefore promising for commercial growing, with the advantage of being resistant to the black Sigatoka and Panama disease.

QoS-driven power control for inter-WBAN interference mitigation

Abstract: Wireless Body Area Networks (WBANs) are usually designed for pervasive healthcare applications. Since the primary traffic in WBAN is vital physiological signals, guaranteeing the Quality of Service (QoS) is crucial while designing WBAN. However, QoS of WBAN will be degraded in strong inter-WBAN interference environment such as hospitals and senior communities, where WBANs are densely deployed. In this paper, by focusing on a more practical WBAN model, we propose a non- cooperative power control game to mitigate inter- WBAN interference, in which the cost function is well designed by considering both QoS requirement and energy constraint. The existence of at least one Nash equilibrium (NE) point for the game is proved and a sufficient condition for the uniqueness of the NE is derived. To guarantee non-cooperative among WBANs, an interference segmentation estimate (ISE) algorithm is proposed to obtain an approximation of the NE point. Simulation results demonstrate the effectiveness of the proposed ISE algorithm.

Birds of Golden Pride Project area, Nzega District, central Tanzania: an evaluation of recolonization of rehabilitated areas

Abstract: In Tanzania, the success of habitat restoration in mining areas to create suitable environmental conditions for wildlife is poorly understood. Between March 2010 and December 2014 bird species were recorded at the Golden Pride Project area, a gold mine in Nzega District, central Tanzania. The aims of this study were to document bird communities in the mine area, and to assess the extent to which rehabilitated areas have been recolonised. Mist netting, point counts, timed species counts and opportunistic observations were used to document 181 species of birds at the mine area. These included two species endemic to Tanzania, the Tanzanian Red-billed Hornbill Tockus ruahae (treated here as a species separate from T. erythrorhynchus , see Kemp & Delport 2002, Sinclair & Ryan 2010) and Ashy Starling Cosmopsarus unicolor . Rehabilitated areas had about half the number of species found in the unmined areas. Bird use of areas under rehabilitation suggests that habitat restoration can be used to create corridors linking fragmented landscapes. Results suggest that as the vegetation of the rehabilitated areas becomes more structurally complex, the number of bird species found there will be similar to those in unmined areas. This study provides a baseline for future monitoring, leading to a better understanding of the process of avian colonisation of rehabilitated areas. Furthermore, results imply that in mining areas it is useful to have an unmined area where vegetation is naturally allowed to regenerate, free of human activity. These unmined areas can later act as source habitats from which birds can disperse into rehabilitation areas once the vegetation structure is sufficiently complex.

Heusler Alloy Ribbons: Structure, Martensitic Transformation, Magnetic Transitions, and Exchange Bias Effect

Abstract: We outline the microstructure, crystal structure, first-order martensitic transformation, and magnetic properties observed in selected Heusler Ni–Mn–Z (Z = In, Sn) alloys produced in ribbon shape by melt spinning. Along with a detailed description of Heusler alloy ribbon production and structural, calorimetric, and magnetic characterization, we highlight various characteristic features associated with the disorder influence on the magnetostructural martensitic transformation related to phase coexistence, metastability, supercooling, and superheating as a consequence of its first-order nature. Magnetic field and annealing effect on the martensitic phase transformation are also analyzed. The understanding of that transition process helps us to explain the exchange bias effect observed in the martensite phase of Ni–Mn–In and Ni–Mn–Sn systems.

Assessing some models for city e-government implementation: a case study

Abstract: The concept of the 'Smart City' calls for the use of information technology to improve administrative decision making, provide services to the citizenry and support other city government organisational changes necessary for better performance. Towards implementing the Smart City concept, the literature on city e-government proposes five models aiming to guide the implementation process. This paper describes a case study on e-government implementation and derived knowledge to assess the usefulness of the proposed implementation models. The results confirm the benefits and limitations of such models and propose a success factor approach representing a major paradigm shift to study and assist e-government implementation. This new approach is expected to produce results more helpful to city administrators attempting to use information technology to improve city government.

Does a Survey Based Capacity Utilization Measure Help Predicting Brazilian Output Gap in Real-Time?

Abstract: The aim of the paper is to assess the informational content of a survey-based measure of the Brazilian manufacturing capacity utilization rate produced by the Brazilian Institute of Economics from Getulio Vargas Foundation. From a theoretical point of view, the survey-based capacity measure should provide meaningful information with respect to the Brazilian business cycle. In this work, we choose to use the output gap as the most comprehensive and convincing proxy of the cyclical situation (Graff and Sturm in CESifo Econ Stud 58(1):220–251, 2012). More specifically, we will refer to a real-time version of the output gap, using an existing real-time GDP data set produced by the Central Bank of Brazil (Cusinato et al. in Empir Econ, 2012). The information efficiency of the real-time output gap estimates is tested checking whether survey data can help producing real-time estimates that are significantly closer to the latest releases. In this sense, the paper provides a significant contribution to the existing literature, extending analysis already available for OECD countries to the Brazilian economy. Our main result is that survey data can indeed help to produce more efficient estimates of the output gap in real time.

Collective Health In Brazil: Analyzing The Institutionalization Process

Abstract: This work first analyzes the construction of a typology of the studies on collective health and its institutionalization process in Brazil, in which three stages are proposed: the preventive project, social medicine and collective health. Secondly, the work examines the phases of institutionalization, disciplinarization and professionalization of collective health in Brazil. Within the institutionalization phase, the study analyzes connectivity and communication, regularization of discourses and practices, the construction of a separate identity and political actions, and the incorporation and legitimation of these elements. It is concluded that the trajectory of the construction of collective health is marked by three dimensions: the theoretical-critical, the political-sanitary and the pedagogical-professional.

Work And Risk Experience Among Northeastern Migrant Works In Sugarcane Plantations In The State Of São Paulo, Brazil

Abstract: Every year thousands of workers from the Brazilian Northeastern states move to the sugarcane plantations in the state of São Paulo to work in sugarcane mills. Most of them are young with little schooling and come from peasant families. Among other things, researchers call attention to the risks to which these workers are submitted, related to transportation conditions, housing and work environment. The organization of work is always focused on increasing the surplus value, which has resulted in the deterioration of the labor force, expressed by several diseases and countless deaths of migrant workers. In the scope of this article, it is our intention to define “risk” concept and relate it to the processes of subjectivities and to understand the meanings that migrant workers attribute to the risks to which they are exposed during the trip and also in workplaces (sugarcane plantations). Regarding methodology, we used a qualitative approach. Data were collected through semi-structured interviews conducted with a sample of 12 migrant workers from the city of Santa Cruz da Baixa Verde (Pernambuco), in the Pajeú microregion, and also of cities located in the microregion of Serra do Teixeira (Paraíba), especially the surrounding areas of Princesa Isabel (state of Paraíba). The data allow us to assert the existence of an intrinsic relationship between the risks they run and the affirmation of the gender identity of the subjects investigated.

Incidence And Mortality Of Children And Teenagers With Aids: Challenges In The Southern Region Of Brazil

Abstract: The objective of this study is to describe the time trend of coefficients of incidence and mortality associated with AIDS in children and adolescents. An ecological time trend study was conducted among individuals under 14 living in the regional context of high incidence of AIDS - Porto Alegre and the State of Rio Grande do Sul - from 1996 to 2012. For this purpose, a segmented regression model was adjusted for age categories and place of residence. AIDS morbidity and mortality indicators in Porto Alegre are still higher than those registered in the State, the southern region and other areas of the country. In Porto Alegre, 59.1% of cases (371/628) occurred in children under four years of age, the incidence showed peaks in the period and the mortality dropped from 9 to 2 per 100,000. A significant decreasing in annual percentage change in mortality was observed especially in children under 1 year of age in Porto Alegre. This drop may be related to prevention and treatment of pregnant women. The challenge is to identify possible fragilities of the STD/AIDS Program and its vulnerable points in order to make specific interventions and investments with a greater impact potential.

Implementation and evaluation of the Landsat Ecosystem Disturbance Adaptive Processing Systems (LEDAPS) model: a case study in the Colombian Andes

Abstract: En este trabajo se hace un analisis de la reflectividad obtenida con una serie de imagenes Landsat procesadas con el modelo LEDAPS en una region de los Andes Colombianos. Fueron calibradas 38 imagenes de los sensores TM y ETM con el modelo LEDAPS con el fin de evaluar las diferencias de reflectividad entre las bandas de un mismo sensor, las diferencias entre sensores, y los patrones temporales. Se utilizaron pruebas estadisticas no parametricas exactas que permitieron concluir: a) la reflectividad superficial entre bandas (1-5 y 7) es distinta y que esta diferencia se mantiene entre escenas de fechas distintas; b) al comparar las bandas de igual longitud de onda entre los sensores TM y ETM+ hay altas similitudes estadisticas entre las bandas; c) las variaciones temporales en reflectividad desde el ano 1986 a 2013 con los sensores estudiados no son significativas. Estos resultados estan sustentados con la implementacion de modelacion robusta con varios metodos resistentes a observaciones inusuales y otros problemas tipicos de la modelacion de minimos cuadrados clasicos.

Portable measurement system of vertical jump using an Inertial Measurement Unit and pressure sensors

Abstract: The physical challenges of human development reflected in the sport are increasingly technology-related. This relationship can be demonstrated in several lines; design on sports elements using high technology as well as sports analysis systems that trying to enhance technical indicators in every discipline. The analysis systems facilitate the feedback process to coaches and athletes, based on mathematical models using derived measures, avoiding precision errors of human observations. One meaningful measure for coaches, strength and conditioning professionals, and sport professionals in general is the vertical jump height. In this paper the initial development of a vertical jump height measurement system is presented, that allows to know the flight height of a person in the development of exercise, and his flight time. The system relies on information from an Inertial Measurement Unit (IMU) consisting of an triaxial accelerometer, a triaxial gyroscope and a triaxial magnetometer and two pressure sensors that fuse the jump measured data. The equipment is completely portable and wireless allowing measurements under standard conditions and these can be developed at the same time with the sporting activity. In average were obtained a flight time of 0.4720s and a maximum height of 0.3160m. The results evidence that these systems based on initiatives of low-cost national technology can be at the level of the products used commercially. Finally, it is important to note that the development of these devices can be complemented with specific applications that automatically process data to support the practice of sports.

Virtual network mapping for reliable multicast services with max-min fairness

Abstract: Network Function Virtualization (NFV) provides an effective way to reduce the network provider's cost by allowing multiple Virtual Networks (VNs) to share the underlying physical infrastructure. In the NFV environment, especially when supporting multicast service over the VNs, reliability is a critical requirement in the process of VN mapping since the failure of one virtual node can cause the malfunction of all the subsequent nodes that receive multicasting data from it. In this paper, for the first time, we study how to efficiently map VNs for reliable multicast services, while taking into consideration the max-min fairness of the reliability among distinct VNs. We propose a Mixed Integer Linear Programming (MILP) model to determine the upper bound on the max-min fairness reliability. In addition, an efficient heuristic, namely Uniform Reliability Mutation based Genetic (URMG) algorithm, is developed to address reliable multicast VN mapping with a low computational complexity. By encoding multicast tree construction and link mapping into path selection, taking into consideration the max-min reliability fairness goal, and the networking reliability factors during mutation, URMG can globally optimize the reliability and its fairness of all the multicast VN requests. Through extensive simulations, we demonstrate that URMG achieves close to the optimal reliability fairness with a much lower time complexity than the MILP and yields a significant performance improvement in terms of reliability fairness, bandwidth consumption and transmission delay comparing with other heuristic solutions.

Cattle Egret Bubulcus ibis interactions with large mammals in the Tarangire-Manyara Ecosystem, Northern Tanzania

Abstract: While Cattle Egrets Bubulcus ibis are globally widespread, their ecology is not fully understood. Surveys of the species were undertaken in November 2012, and April 2013, in Lake Manyara National Park, Manyara Ranch, and outside the two protected areas. We investigated the effects of host identity, habitat type and host animal behaviour on Cattle Egret numbers and distribution. Cattle Egrets associated more with grazers than with mixed-feeders or browsers, and chose large-bodied animals over small-bodied ones. They preferred wetland and grassland, over bushland. These findings underscore the importance of wetland management and the maintenance of healthy grasslands for the future of Cattle Egrets. Declines in large-bodied mammal species are likely to negatively affect them.

Brazil Is A Sexual Paradise - For Whom?

Abstract: Starting by confronting two contrasting images of Brazilianness associated with sexuality, I develop a discussion about the changing theoretical and political meanings that can take on reflections regarding the connections between pleasures and dangers, concerning both feminism and sexual and gender diversity issues. I try to explore the constant and productive tension between these contradictory ideals as narratives, which are effective in constructing social ways of understanding and experiencing gender and sexuality.