Inácio Maria Dal Fabbro

Laser speckle techniques in quality evaluation of orange fruits

This work presents a study of a new technology applied in quality tests of oranges. Evaluations were performed using a nondestructive and noninvasive method based on the interpretation of an optical phenomenon that occurs when the fruit is illuminated with coherent light, referred as biospeckle. The speckle patterns of laser light scattered in orange fruits have been measured through their quantification. For the quantification of the variation by biospeckle, the autocorrelation function and the modified occurrence matrix were used. From these functions, two parameters were obtained: the statistical cummulant and the moment of inertia, calculated from the modified occurrence matrix. These values were used as quality and senescence indicators for the specimens and were compared with other parameters, as total soluble solids, total acidity, the penetration force and the storage period. It was observed that the moment of inertia and statistical cummulant decrease during the storage period. Since senescence is dependent on the storage period, it was possible to observe that the measure of the dynamic speckle varies for fruits as their quality decrease, and also the values change with the position where the images are taken.

Image processing techniques for lemons and tomatoes classification

Vegetable quality is frequently referred to size, shape, mass, firmness, color and bruises from which fruits can be classified and sorted. However, technological by small and middle producers implementation to assess this quality is unfeasible, due to high costs of software, equipment as well as operational costs. Based on these considerations, the proposal of this research is to evaluate a new open software that enables the classification system by recognizing fruit shape, volume, color and possibly bruises at a unique glance. The software named ImageJ, compatible with Windows, Linux and MAC/OS, is quite popular in medical research and practices, and offers algorithms to obtain the above mentioned parameters. The software allows calculation of volume, area, averages, border detection, image improvement and morphological operations in a variety of image archive formats as well as extensions by means of “plugins” written in Java.

Rheological characterization of chicory root (Cichorium intybus L.) inulin solution

Inulin is a polysaccharide frequently used as a sugar or fat replacer in the food industry, which offers the advantage of a functional effect similar to those of dietary fibers. By cooling or freezing an inulin concentrated solution, a more concentrated solution precipitates as a paste-like substance, while the liquid phase forms a diluted solution. In this work, the effect of storage temperature of inulin concentrated solution as well as temperature on the rheological behavior of liquid and precipitated phases obtained from a process of phase separation were evaluated. The precipitated phase of inulin was evaluated under two conditions: pure and formulated with encapsulating agents. It was observed that a reduction in storage temperature resulted in a higher inulin precipitation, which produced higher apparent viscosity values for the precipitated phase. All the samples analyzed had a shear-thinning rheological behavior.

Determinação da topografia de uma fruta pela técnica de moiré de sombra com multiplicação de franjas

As tecnicas de moire (TM) sao um conjunto de tecnicas, baseadas no fenomeno de moire, mais comumente utilizadas em perfilometria, devido a sua simplicidade e rapidez de medicao. O fenomeno de moire consiste na interferencia causada pela sobreposicao de duas estruturas periodicas (reticulos), sendo a TM de sombra com multiplicacao de franjas mais sensivel que os metodos tradicionais, alem de diminuir os efeitos da diferenca de iluminacao na superficie do objeto em estudo. Objetivou-se com este trabalho gerar um Modelo Digital de Elevacao (MDE) de uma pera pela TM de sombra com multiplicacao de franjas e compara-lo a um outro modelo gerado a partir de um scanner 3D. Para este trabalho, foram utilizados um modelo de uma pera, em escala 1:1, confeccionado em parafina e um esquema experimental constituido de um reticulo de moire, iluminador e câmera fotografica digital. Pelos resultados, verifica-se uma alta correlacao entre os MDE obtidos pelos dois metodos. A TM de sombra com multiplicacao de franjas gerou um MDE que reproduz satisfatoriamente a topografia da pera.

Fruit Surface Topographic Survey Supported By a Phase Shifting Projection Moiré Technique

The pertinent literature discloses relevant research work on plant organs shape survey, considered important to all sort of crop mechanical handling, aiming mechanical bruising minimization and losses as consequences. A sequence of research work was proposed by Lino et ali, 2002 [3] starting with a topographic survey of a virtual surface (1), followed by a survey of solid symmetric figures surfaces (2), a fruit surface survey (3) and finally, the generation of a 3D digital model (4). In testing virtual surfaces, a Ronchi grid named G1 was generated in a PC, from which other grids referred as G2, G3, and G4 were set out of phase by 1/4, 1/2 and 3/4 of period from G1. However, in the present case, i.e. the step (3), grid G1 was projected onto a fruit surface instead of being virtually distorted. Projected grid was named Gd. The difference between Gd and G1 followed by filtration, generated de moire fringes M1. The same procedure generated the fringes M2, M3 and M4 from Gd. Fringes are out of phase one from ...

TÉCNICA DE MOIRÉ APLICADA AL ANÁLISIS DE ESFUERZOS DE COMPRESIÓN EN EL BAMBÚ GUADUA

Bamboo is considered an important raw material in developing countries because its physical characteristics associate lightness with high mechanical resistance. However its behavior obtained from mechanical tests is not yet well defined. This research work had the objective of evaluating bamboo (Guadua angustifolia) testing specimens under simple uniaxial compression loading. Shadow moire optical methods had been employed to generate deformation mapping as function of knots (0, 1 or 2). Obtained results indicate that the technique is well adequate in generating iso-deformation contour lines in bamboo specimens.

Nitrogen availability, leaf life span and nitrogen conservation mechanisms in leaves of tropical trees

Evergreen species of temperate regions are dominant in low-nutrient soils. This feature is attributed to more efficient mechanisms of nutrient economy. Nevertheless, the cashew (Anacardium occidentale- Anacardiaceae), a deciduous species, is native to regions in Brazil with sandy soil, whilst the annatto (Bixa orellana- Bixaceae), classified as an evergreen species native to tropical America, grows spontaneously in regions with more humid soils. Evergreens contain robust leaves that can resist adverse conditions for longer. The physical aspects of the leaves and mechanisms of nutrient economy between the two species were compared, in order to verify whether the deciduous species had more efficient mechanisms that might explain its occurrence in regions of low soil fertility. The mechanisms of nitrogen economy were also compared for the two species at available concentrations of this nutrient. The following were analysed: (i) leaf life span, (ii) physical leaf characteristics (leaf mass per area, and rupture strain), (iii) nitrogenous compounds (nitrogen, chlorophyll, and protein), (iv) nitrogen conservation mechanisms (nitrogen resorption efficiency, resorption proficiency, and use efficiency), and (v) nitrogen conservation mechanisms under different availability of this mineral. The higher values of leaf mass per area and leaf rupture strain found in A. occidentale were related to its longer leaf life span. A. occidentale showed lower concentrations of nitrogen and protein in the leaves than B. orellana. Under lower nitrogen availability, A. occidentale had higher nitrogen resorption proficiency, nitrogen use efficiency and leaf life span than B. orellana. These characteristics may contribute to the adaptation of this species to sandy soils with low nitrogen content.

Three-Dimensional Reconstruction of Live Fish through the Moiré Technique

Currently, in fish farms, the controls of the physical characteristics of the fishes, for example, size and mass are made by means of the operation of fish removal, in which the tanks are emptied to capture the animals and perform the biometry. This operation demands large volumes of water and generates effluent containing high concentrations of organic matter and nutrients that can contribute to the deterioration of water quality in the recipient bodies. Therefore, the development of technologies that use digital image processing, such as the moiré technique and image analysis, can be important allies for the preservation of environmental quality by avoiding the fish removal and the discharge of effluents, increasing productivity due to optimization of the time and still the saving of water. To obtain the images a 9-liter glass aquarium, a support for notebook and light projector, a digital camera brand Samsung Galaxy Camera 2 were used. The objective of this work was to obtain the three-dimensional reconstruction of live fish in aquariums. In the future, the technique can be developed to obtain the mass and the volume of the fish in fish tanks, replacing the fish removal, allowing the preservation of water resources.

Static tensioning promotes hamstring tendons force relaxation more reliably than cycling tensioning

BACKGROUND Graft elongation might be a major reason for increased anterior laxity after anterior cruciate ligament (ACL) reconstruction. This study analyzed the force relaxation values and their stabilization when single strands of the gracilis and semitendinosus tendons underwent cyclic and static tensioning at 2.5% strain level, and compared the efficiency of static and cyclic tensioning in promoting force relaxation. METHODS Eighteen gracilis tendons and 18 semitendinosus tendons from nine male cadavers (mean age: 22.44years) were subjected to 10 in vitro cyclic loads at 2.5% strain level, or to a static load at 2.5% strain level. RESULTS During cyclic loading, the reduction in force values tended to stabilize after the sixth cyclic load, while, in the case of static loading, this stabilization occurred by the second minute. Comparing static and cyclic loading, the gracilis tendon had similar mechanical responses in both conditions, while the semitendinosus tendon showed greater force relaxation in static compared with cyclic loading. CONCLUSIONS Considering that the semitendinosus tendon is the main component of the hamstring graft, its biomechanical response to loading should guide the tensioning protocol. Therefore, static tensioning seems more effective for promoting force relaxation of the semitendinosus tendon than cyclic tensioning. The gracilis tendon showed a similar mechanical response to either tensioning protocols.

Papaya (Carica papaya) Classification by Software

In this paper, it suggested the selection of papayas by image processing employing low-cost equipment for data acquisition. This may allow the process automation selection and classification of agricultural products for small farmers or small traders. The objective of this work was to evaluate two papaya varieties (“Solo” and “Formosa”) using image programs for selection of miscellaneous format detection and fruit mapping coloration. The experiment occurred at an optic laboratory and it used a diffused light, camera, computer and papaya fruits, and for image processing, the ImageJ software, in addition to computer programs that have been developed for image processing. The detection of varied sizes and the fruit classification by mapping color were conducted using the software. The program for evaluating the two varieties format worked with 100% of the fruits and the one for mapping coloration with 80% correct results. These results showed that the program had low error and could be used for fruit selection.