Block freeze-concentration of coffee extract: Effect of freezing and thawing stages on solute recovery and bioactive compounds

Coffee extract was freeze-concentrated using the total block technique. The effects of four parameters were evaluated: the initial coffee mass fraction (5 and 15% w/w), the cooling temperature ( 10 and 20 C), the heating temperature (20 and 40 C) and the freezing direction (parallel and counter-flow to the thawing direction). The solid concentration was measured during the thawing stage to quantify the solute recovery and the concentration index for one stage of freeze concentration. The coffee mass fraction, the freezing direction and the cooling temperature significantly influenced the solute recovery. A concentration index between 1 and 2.3 was obtained in one cycle. The effect of block freeze concentration on the bioactive compound concentration and the antioxidant activity was measured. The coffee bioactive compounds were distributed in proportion to the total solid content in the ice and liquid. Therefore, block freeze concentration is an effective technique to preserve functional properties of coffee extracts.Postprint (published version

Plataforma logística regional de distribución de contenedores para la eficiencia de los buques que pasan por el Puerto Corozal

Visita Técnica InternacionalEste proyecto se orientó a la aplicación de un algoritmo genético, lo cual apoya la plataforma logística regional de distribución de contenedores para la eficiencia de los buques que pasan por el puerto de Corozal en Panamá, estableciendo un análisis de diversos algoritmos e identificando el algoritmo genético como el más eficiente para la operación y optimización de los procesosINTRODUCCIÓN 1. GENERALIDADES 2. MODELOS ALGORITMICOS 3. ANALISIS DE LA INFORMACIÓN 4. RESULTADOS Y ESTRUCTURA DE LA ESTRATEGIA 5. CONCLUSIONES 6. RECOMENDACIONES 7. TRABAJOS FUTUROS BIBLIOGRAFÍA ANEXOSPregradoIngeniero de Sistema

Fluid Communities: A Competitive, Scalable and Diverse Community Detection Algorithm

We introduce a community detection algorithm (Fluid Communities) based on the idea of fluids interacting in an environment, expanding and contracting as a result of that interaction. Fluid Communities is based on the propagation methodology, which represents the state-of-the-art in terms of computational cost and scalability. While being highly efficient, Fluid Communities is able to find communities in synthetic graphs with an accuracy close to the current best alternatives. Additionally, Fluid Communities is the first propagation-based algorithm capable of identifying a variable number of communities in network. To illustrate the relevance of the algorithm, we evaluate the diversity of the communities found by Fluid Communities, and find them to be significantly different from the ones found by alternative methods.Comment: Accepted at the 6th International Conference on Complex Networks and Their Application

Ice morphology modification and solute recovery improvement by heating and annealing during block freeze-concentration of coffee extracts

Several treatments on ice blocks can be applied during block freeze-concentration to increase the solute recovery from the ice. In the present study, the changes in the ice block’s temperature and the application of annealing during the block freeze-concentration of aqueous coffee extracts were studied. The ice block was subjected to heating and annealing prior to the thawing stage. The effect of coolant temperature during ice block heating (T = -10 and -5 °C) and the application of annealing (+, -) on solute recovery and ice structure morphology was evaluated. The use of annealing during block freeze-concentration modified the ice crystal morphology and increased the solute recovery only when it is applied at the highest temperature. In general, the annealing process increased the size and circularity of the ice crystals, consequently improving the solute recovery. Thus, annealing can be used to increase the solute recovery during block freeze-concentration.Postprint (published version

Estudi comparatiu de les diferents solucions energètiques per a la propulsió de vehicles automòbils

En el projecte redactat a continuació es realitzarà un estudi comparatiu sobre les diferents energies de propulsió per a vehicles automòbils. Primer de tot es durà a terme un estudi previ per conèixer més a fons les característiques de cada una d’aquestes energies i diferents aspectes com a quina matèria primera estan associades, com s’apliquen en el vehicle i el seu funcionament. Posteriorment s’iniciarà l’estudi comparatiu de les diferents energies, començant per diferents característiques tècniques i finalitzant amb l’estudi econòmic dels costos des del punt de vista de tres aspectes essencials: el cost de l’energia, el cost de manteniment i els costos pel medi ambient. Finalment s’analitzaran els resultats dels costos obtinguts en l’estudi comparatiu per extreure la conclusió de quina d’elles té uns costos més elevats i quina és la més econòmica. I indicar els principals avantatges i inconvenients de cada una de les energies