IMAGE SEGMENTATION USING A MODIFIED SPLIT AND MERGE TECHNIQUE

In this paper, a reformulation of the processes that composed the split and merge technique is proposed. A recursive split process is done first; then, after the merge process, a segmentation of the image is obtained. This is possible because the merging is implemented like a growth process, so the grouping has been eliminated. The use of a complete quadtree helps to achieve the reformulation. The determination of the region uniformity in each process is carried out with a different predicate, because of the different nature of the two processes. Experiments on a blocks world image and an industrial parts image are included to show the result of applying the algorithm.     

Viability of microencapsulated Bifidobacterium animalis ssp. lactis BB12 in kefir during refrigerated storage

The viability of free and immobilized cells of Bifidobacterium animalis ssp. lactis BB12 incorporated into kefir was studied for 28 days during refrigerated storage. The immobilized bifidobacteria were added directly to previously prepared kefir. Titratable acidity, pH, ethanol, fat, protein and lactose were evaluated in the kefir with bifidobacteria after the storage. The survival of the free and microencapsulated bifidobacteria was evaluated during the storage period and in simulated gastric juice. The pH of kefirs ranged from 4.3 to 4.6. Encapsulation improved significantly the survival of bifidobacteria during exposure to nisin, during the storage period and in simulated gastric juice.     

EVALUATION OF TOMATO QUALITY DURING STORAGE BY ACOUSTIC IMPULSE RESPONSE

The aim of this research was to evaluate the ability of acoustic impulse response to monitor "Heatwave" tomato quality during storage. The tomato was excited and the response signal is captured using the film sensors. The results showed that acoustic impulse response parameters (dominant frequency, firmness index and elasticity coefficient) of "Heatwave" tomato decreased with storage time. The dominant frequency, firmness index and elasticity coefficient had no correlation with soluble solids contents or pH, but had a good correlation with compression force and puncture force. There was a better correlation between elasticity coefficient and compression force (or puncture force); hence, elasticity coefficient could be a better index of "Heatwave" tomato firmness. The acoustic impulse response is a potential factor in order to determine the firmness of "Heatwave" tomato.

PRACTICAL APPLICATIONS

Tomato firmness is an important characteristic because firmness of tomato flesh influences the mouth sensory feel. This results showed that acoustic impulse response parameters (dominant frequency, firmness index and elasticity coefficient) of "Heatwave" tomato decreased with storage time. The dominant frequency, firmness index and elasticity coefficient had not correlation with soluble solids contents or pH, but had a good correlation with compression force and puncture force. There were better correlation between elasticity coefficient and compression force (or puncture force), and hence elasticity coefficient could be a better index of "Heatwave" tomato firmness. The acoustic impulse response is potential to determine the firmness of "Heatwave" tomato.     

SCHEDULING OF CONTINUOUS PARALLEL LINES IN THE EVAPORATION SECTION OF SUGAR PLANTS

Cost reduction in sugar industries can be achieved just by adjusting and optimizing structures and/or key process variables to assure maximum use of the sugar formed in the field. The evaporation section is the critical stage for efficient management of water and energy resources. Thus, the selected case study addresses the optimization of the operation of continuous evaporation units working in parallel and presenting a decrease of in efficiency with time. The problem was solved through mathematical programming that obtained optimum values for the operating variables. Therefore, it was necessary to mathematically formulate the optimization problem and to model the operations under study. A mixed integer nonlinear programming model (MINLP) was used in order to meet the targets. Also, a technical objective function with economical background was developed. The industrial implementation required as well the conception and development of a user-friendly decision-making tool to facilitate the routine work and to allow plant managers to check, accept, and put into practice the solution proposed. The application of the presented strategies to an industrial case study demonstrates the efficiency and potential of the approach adopted.     

Anticorrosives, encapsulates, catalytic supports and other novel nanostructured materials

A phenolic-formaldehydic resin (PFR) of the Novolac-type and modified through the attachment of carboxylic end groups (MPR), is used to tailor the morphological and optical properties of sol–gel synthesized silica materials. Silica microparticles are produced from alkoxide precursors in the presence of PFR or MPR resins, leading to a final material consisting of SiO₂ globules entangled inside a polymerized resin matrix. Under appropriate experimental conditions, chemical bonds can be established between the SiO₂ silanol surface groups and the MPR carboxylic chains, to render SiO₂/MPR core-shell-type compounds. The presence of PFR or MPR resins during the sol–gel production of silica microspheres allows to control: (i) the sizes of final SiO₂ particles and (ii) the transparency or opacity properties of the final hybrid products. In this way, either opaque or transparent solid substrates can be obtained, depending on the amounts of reactants used to prepare the hybrid specimens. Solid MPR and SiO₂/MPR samples were characterized by infrared spectroscopy, thermogravimetric analysis and scanning electron microscopy to determine chemical and textural properties of the hybrid substrates. Under appropriate experimental conditions, chemical bonds could be established between the SiO₂ silanol surface groups and the MPR carboxylic chains, to render SiO₂/MPR core-shell-type compounds.     

<i>Agrobacterium rhizogenes</i> vs auxinic induction for <i>in vitro</i> rhizogenesis of <i>Prosopis chilensis</i> and <i>Nothofagus alpina</i>

The induction and improvement of in vitro rhizogenesis of microshoots of Prosopis chilensis (Mol.) Stuntz and Nothofagus alpina (Poep. et Endl. Oerst.) were compared using Agrobacterium rhizogenes (Ar) versus indole-3-butyric acid (IBA) in the culture media. Microshoots of P. chilensis (1-2 cm length), coming from in vitro grown seedlings, were cultivated in a modified Broadleaved Tree Medium (BTMm) containing half salt concentration of macronutrients and 0.05 mg.L^-1 benzilaminopurine (BAP). After 30 days, microshoots with 2-4 leaves were selected and cultured in BTMm-agar in presence or abscense of Ar and in combination with IBA. For N. alpina, the apical shoots with the first 2 true leaves, from 5 weeks old seedlings, were cultured in the abovementioned medium, but with 0.15 mg.L^-1 of BAP. After 2 months, microshoots with 2-3 leaves were selected and cultured in BTMm-agar, supplemented with 5 mg.L^-1 IBA or in liquid BTMm on perlite and, in the presence or absence of A. rhizogenes (Ar) and in combination with 3 mg.L^-1 IBA. Rooting in P. chilensis reached 100.0% when Ar infection was produced in the presence of IBA, increasing both, the number and dry weight of roots. In N. alpina, 90.0% of rooting efficiency was obtained when Ar infection was produced in liquid culture and in the absence of auxin.     

MULTI-AGENT SYSTEMS FOR DECISION SUPPORT: A CASE STUDY IN THE TRANSPORTATION MANAGEMENT DOMAIN

This article describes how agent and knowledge technology can be used to build advanced software systems that support operational decision making in complex domains. In particular, we present an abstract architecture and design guidelines for agent-based decision support systems. We illustrate our approach with a case study in the transportation management domain.     

Phytoplankton pigment patterns in the Canary Islands area as determined using Coastal Zone Colour Scanner data

Abstract

Data from the Nimbus-7 Coastal Zone Colour Scanner (CZCS) were analyzed to determine the phytoplankton pigment patterns in the ocean surrounding the Canary Islands. Two different pattterns were observed in this region. One pattern was associated with the influence of the northwest African coastal upwelling system on the ocean surrounding the Canary Islands and the other was associated with individual islands, probably due to the disruptive effect of the Canary Islands on the flow of the Canary Current