Tratamento de imagens landsat para identificação de açaizal em floresta de várzea.

O estuário amazônico é formado por um emaranhado de ilhas, onde existem as florestas de várzeas, áreas de especial importância devido aos elevados valores de produtividade e fertilidade dos solos. Entre os produtos não madeireiros mais importantes dessas áreas destaca-se o açaizeiro (Euterpe oleracea). Nos últimos anos verifica-se uma grande expansão dos açaizais como resultado do crescimento do mercado do açaí no estado do Amapá. Tal expansão pode ser explicada tanto pelo plantio de novas áreas como pelo manejo de açaizais nativos, resultando no aumento da densidade de indivíduos de açaí e redução dos indivíduos das espécies florestais. O mapeamento realizado por meio de imagens de sensoriamento remoto, ainda que com limitações, pode facilitar a avaliação mais aprofundada das áreas de várzeas, tendo em conta o potencial produtivo da mesma. O presente estudo tem como foco os açaizais, nativos e manejados, concentrados na foz do rio Mazagão Velho, uma área de várzea localizada no sudeste do município de Mazagão, estado do Amapá, no estuário do rio Amazonas, onde estão estabelecidos transectos para estudo de manejo florestal e ecologia em áreas de várzea por meio do projeto Florestam executado pela EMBRAPA-Amapá. Para o estudo utilizou-se imagens Landsat 5/TM, do ano 2004 e 2008, selecionadas considerando a menor cobertura de nuvens possível, e imagem Landsat 8/OLI para o ano 2013. O processamento digital das imagens incluiu correção geométrica, fusão entre imagens de 30 e 15m, transformação para imagens-fração de vegetação, solo e agua pura, seguido da aplicação de técnicas de segmentação e classificação por região, com a utilização dos softwares SPRING e ENVI. O mapa resultante da classificação foi organizado em classes de cobertura de solo: floresta de várzea, açaizal em várzea, solo exposto e água. A validação do mapa foi estimada a partir de informações coletadas em campo: pontos de descrição da classe de cobertura de açaizal em várzea. Esses pontos permitiram a geração da matriz de confusão para avaliar a qualidade da classificação. O trabalho apresenta o mapa resultante do processamento das imagens e os resultados mostram que a cobertura de açaizal em várzea sofreu aumento significativo nos últimos anos.GC102

Assessing 3D tunnel position in ACL reconstruction using a novel single image 3D-2D registration

Poster Session: 2D/3D and FluoroscopyConference Theme: Image-Guided Procedures, Robotic Interventions, and ModelingThe routinely used procedure for evaluating tunnel positions following anterior cruciate ligament (ACL) reconstructions based on standard X-ray images is known to pose difficulties in terms of obtaining accurate measures, especially in providing three-dimensional tunnel positions. This is largely due to the variability in individual knee joint pose relative to X-ray plates. Accurate results were reported using postoperative CT. However, its extensive usage in clinical routine is hampered by its major requirement of having CT scans of individual patients, which is not available for most ACL reconstructions. These difficulties are addressed through the proposed method, which aligns a knee model to X-ray images using our novel single-image 3D-2D registration method and then estimates the 3D tunnel position. In the proposed method, the alignment is achieved by using a novel contour-based 3D-2D registration method wherein image contours are treated as a set of oriented points. However, instead of using some form of orientation weighting function and multiplying it with a distance function, we formulate the 3D-2D registration as a probability density estimation using a mixture of von Mises-Fisher- Gaussian (vMFG) distributions and solve it through an expectation maximization (EM) algorithm. Compared with the ground-truth established from postoperative CT, our registration method in an experiment using a plastic phantom showed accurate results with errors of (-0.43°±1.19°, 0.45°±2.17°, 0.23°±1.05°) and (0.03±0.55, -0.03±0.54, -2.73±1.64) mm. As for the entry point of the ACL tunnel, one of the key measurements, it was obtained with high accuracy of 0.53±0.30 mm distance errors. © 2012 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).published_or_final_versionSPIE Medical Imaging 2012, San Diego, CA., 4-9 February 2012. In Progress in Biomedical Optics and Imaging, 2012, v. 8316, art. no. 83162

Life Goes On: Psychosocial Suffering from war and healing pathways in northern Rwanda.

This thesis explores the ways in which local communities in Musanze, northern Rwanda, heal psychosocial suffering from the war period between 1990 and 2000 in the context of limited humanitarian aid. Employing a narrative approach, it unpacks experience of psychosocial suffering, elaborates the ways in which communities heal themselves, and describes the meaning of ‘healing’ in the light of local views of morality, life and death. Qualitative analysis drew on participant observation, in-depth interviews, and focus-group discussions based on ten months of ethnographic fieldwork, which built on prior life and work experience in the field over two years. Findings first describe local conceptualizations of psychosocial sufferings. These fell on a spectrum constructed by the degree of social disconnection reported by participants and how far their thoughts and memories were oriented towards a wounded past. A key element of suffering was the literal ‘unspeakability’ of many wounds due to politically-sensitive circumstances. This related to difficulties in making sense of what they have experienced. Narratives of healing pathways described a common theme of leaving the past behind and going forward to the future through participation in different communities, including church-based groups, traditional mutual-saving groups, and neighbourhood relationships. In the context of the unspeakability of many wounds, communities provided alternative ways of healing from ‘speaking’ of wounds directly. These include: allowing members to make sense of their sufferings through religious and traditional activities, everyday-life practices, and life-event ceremonies. The thesis highlights that, in this setting, healing is not conceptualized as ‘recovery’ as assumed by Western theories, but rather, as a trajectory of ‘life goes on’: that is, that time continues into the future. In this emic experience of healing, the focus is not on traumatic time but on time ‘being lived’ as part of life, and a series of lives handed over from generation to generation, through sharing everyday life and significant life events. In other words, healing can take place through social connection in a wider time-scale than trauma

Dehydrogenation Catalyst for Organic Hydride on the Basis of Superheated Liquid-Film Concept

Reversible reaction couples of hydrogenation and dehydrogenation of organic compounds e.g. methylcyclohexane and toluene, or 2-propanol and acetone, are described in terms of hydrogen supplier to fuel cells, which will satisfy our demands of combined heat and power at various compact sizes. Carbon supported nano-sized metal particles, wetted with the liquid substrate in a reactor, was used for conversion of organic hydrides into hydrogen and organic compounds, being separable by distillation. Vigorous nucleate boiling is important for heat transfer as well as for irreversible bubble evolution, leading hydrogen to the vapor phase. Once the bubble is broken at the interface, catalytic hydrogenation will be prohibited, because gaseous hydrogen is unable to dissolve into the boiling liquid. Catalytic dehydrogenation under superheated liquid-film conditions can thus convert low-quality heats into hydrogen energy

Correspondenceless 3D-2D registration based on expectation conditional maximization

Cum Laude Poster AwardConference Theme: Visualization, Image-Guided Procedures, and Modeling3D-2D registration is a fundamental task in image guided interventions. Due to the physics of the X-ray imaging, however, traditional point based methods meet new challenges, where the local point features are indistinguishable, creating difficulties in establishing correspondence between 2D image feature points and 3D model points. In this paper, we propose a novel method to accomplish 3D-2D registration without known correspondences. Given a set of 3D and 2D unmatched points, this is achieved by introducing correspondence probabilities that we model as a mixture model. By casting it into the expectation conditional maximization framework, without establishing one-to-one point correspondences, we can iteratively refine the registration parameters. The method has been tested on 100 real X-ray images. The experiments showed that the proposed method accurately estimated the rotations (< 1°) and in-plane (X-Y plane) translations (< 1 mm). © 2011 SPIE.published_or_final_versionThe SPIE Medical Imaging 2011, Lake Buena Vista, FL., 12-17 February 2011. In Progress in Biomedical Optics and Imaging, 2011, v. 7964, art. no. 79642

Simulation and Design of a Simple and Easy-to-use Small-scale Neutron Source at Kyoto University

AbstractA simple and easy-to-use compact neutron source based on a low power level proton accelerator (proton energy 3.5 MeV and 0.35kW beam power) at Kyoto University was designed with the conception of low cost, compact size, high safety and intensive thermal neutron flux via Monte Carlo method with PHITS code. By utilizing (p, n) reactions in a beryllium target coupled to a polyethylene moderator and graphite reflector with a wing configuration, this facility is expected to produce time-averaged thermal neutron fluxes suitable for neutron scattering and development of instrumentation, and play a role in educating students in neutron science and performing research with neutrons. Borated polyethylene (BPE) and ordinary concrete were combined to shield the neutron and photon. By using niobium as target backing and water as cooler, it is promising to cope with the problem of thermal damage and hydrogen embrittlement damage. The sizes of moderator and reflector are optimized to have thermal neutron flux as high as possible, while keeping the low ratio of fast neutron flux to thermal neutron flux. The neutron and gamma dose equivalent rates were evaluated and the current shielding configuration is acceptable

Measurement of neutron diffraction with compact neutron source RANS

Diffraction is used as a measurement technique for crystal structure. X-rays or electron beam with wavelength that is close to the lattice constant of the crystal is often used for the measurement. They have sensitivity in surface (0.01mm) of heavy metals due to the mean free path for heavy ions. Neutron diffraction has the probe of the internal structure of the heavy metals because it has a longer mean free path than that of the X-rays or the electrons. However, the neutron diffraction measurement is not widely used because large facilities are required in the many neutron sources. RANS (Riken Accelerator-driven Compact Neutron Source) is developed as a neutron source which is usable easily in laboratories and factories. In RANS, fast neutrons are generated by 7MeV protons colliding on a Be target. Some fast neutrons are moderated with polyethylene to thermal neutrons. The thermal neutrons of 10meV which have wavelength of 10nm can be used for the diffraction measurement. In this study, the texture evolution in steels was measured with RANS and the validity of the compact neutron source was proved. The texture of IF steel sheets with the thickness of 1.0mm was measured with 10minutes run. The resolution is 2% and is enough to analyze a evolution in texture due to compression/tensile deformation or a volume fraction of two phases in the steel sample. These results have proven the possibility to use compact neutron source for the analysis of mesoscopic structure of metallic materials

Apoptosis and p53 status predict the efficacy of postoperative administration of UFT in non-small cell lung cancer

To examine whether efficacy of postoperative oral administration of UFT, a 5-fluorouracil derivative chemotherapeutic agent, may be influenced by incidence of apoptosis (apoptosis index) or apoptosis-related gene status (p53 and bcl-2) of the tumour, a total of 162 patients with pathologic stage I non-small cell lung cancer were retrospectively reviewed. UFT was administrated postoperatively to 44 patients (UFT group), and not to the other 118 patients (Control group). For all patients, 5-year survival rate of the UFT group (79.9%) seemed higher than that of the Control group (69.8%), although without significant difference (P = 0.054). For patients with higher apoptotic index, 5-year survival rate of the UFT group (83.3%) was significantly higher than that of the Control group (67.6%, P = 0.039); for patients with lower apoptotic index, however, there was no difference in the prognosis between these two groups. Similarly, UFT was effective for patients without p53 aberrant expression (5-year survival rates: 95.2% for the UFT group and 74.3% for the Control group, P = 0.022), whereas not effective for patients with p53 aberrant expression. Bcl-2 status did not influence the efficacy of UFT. In conclusion, apoptotic index and p53 status are useful factors to predict the efficacy of postoperative adjuvant therapy using UFT. © 2001 Cancer Research Campaign http://www.bjcancer.co

Multilayer gas cells for sub-Doppler spectroscopy

We have carried out theoretical research on ultra-high resolution spectroscopy of atoms (or molecules) in the suggested cell with a series of plane-parallel thin gas layers between spatially separated gas regions of this cell for optical pumping and probing. It is shown the effective velocity selection of optically pumped atoms because of their specific transit time and collisional relaxation in such a cell, which lead to narrow sub-Doppler resonances in absorption of the probe monochromatic light beam. Resolution of this spectroscopic method is analyzed in cases of stationary and definite nonstationary optical pumping of atoms by the broadband radiation versus geometrical parameters of given cells and pumping intensity. The suggested multilayer gas cell is the compact analog of many parallel atomic (molecular) beams and may be used also as the basis of new compact optical frequency standards of high accuracy.Comment: 12 pages, 4 figure

CANGAROO-III Observation of TeV Gamma Rays from the vicinity of PSR B1 706-44

Observation by the CANGAROO-III stereoscopic system of the Imaging Cherenkov Telescope has detected extended emission of TeV gamma rays in the vicinity of the pulsar PSR B1706$-$44. The strength of the signal observed as gamma-ray-like events varies when we apply different ways of emulating background events. The reason for such uncertainties is argued in relevance to gamma-rays embedded in the "off-source data", that is, unknown sources and diffuse emission in the Galactic plane, namely, the existence of a complex structure of TeV gamma-ray emission around PSR B1706$-$44.Comment: 10 pages, 13 figures, to be published in Ap