A generic library of problem solving methods for scheduling applications

In this paper we propose a generic library of problem-solving methods for solving scheduling applications. Some attempts have been made in the past at developing a library of scheduling problem-solvers but in some cases these earlier proposals subscribe to a specific application domain of scheduling, which restricted their reusability, while in some other cases they subscribe to the specific problem-solving technique which may be applicable only to a subset of the space of scheduling problems. Finally all the existing scheduling libraries fail to provide an adequate degree of detail and precision. In our approach we subscribe to the Task-Method-Domain-Application knowledge modeling framework which provides a structured organization for the different components of the library. At the task level, we constructed a generic scheduling task ontology to formalize the space of scheduling problems. At the method level, we constructed a generic problem-solving model of scheduling that generalizes from the variety of approaches to scheduling problem-solving, which can be found in the literature. And, then seven knowledge-intensive methods are developed as a specialization of the generic problem-solving model of scheduling. Finally, we validated our library on a number of applications to demonstrate its generic nature and effective support for developing scheduling applications

Trilhas ecológicas: metodologias e ferramentas de comunicação para a educação ambiental.

bitstream/item/38830/1/FOL200936.pd

Maize (Zea mays L) cultivars nutrients concentration in leaves and stalks

There is pressure for crop residue removal for use as biofuel, animal feed, animal bedding and many other func¬tions which may increase nutrient export. However, there is little information about nutritional composition of maize stover considering the wide variability of cultivars used. The aim of this study was to evaluate the influence of maize cultivar on macronutrient (P, K, Ca, and Mg), micronutrient (Fe, Mn, Zn, and Cu) and Na concentration in leaves and stalks. We selected five pairs of cultivars, ranging from creole to high potential hybrid (creole, commer¬cial variety, single, double and triple cross hybrid). The cultivars were cropped under field conditions in high fertile Rhodic Ferralsol Eutric during two growing seasons. The first was characterized by severe drought (2005/2006) while the second with an abundant water supply (2006/2007). The leaf and stalk concentrations of P, K, Ca, Mg, Fe, Mn, Na, Zn, Cu, and C/P ratio were quantified at maturation stage. The results indicated that the P concen¬tration in leaves and stalks was inversely related to the technological level when simple hybrid was compared to creole cultivars. Similar behavior was observed for K in the leaf and stalk tissues. For Ca, Mg, Fe, Mn, Zn, Cu, and Na, it was not possible to establish the influence of maize selection. The C/P ratio of leaves and stalks underwent influence of the technological level with high values for simple hybrids. Maize selection seems to decrease P and K concentration for two major residue fractions, leaves and stalks

Evaluating the semantic web: a task-based approach

The increased availability of online knowledge has led to the design of several algorithms that solve a variety of tasks by harvesting the Semantic Web, i.e. by dynamically selecting and exploring a multitude of online ontologies. Our hypothesis is that the performance of such novel algorithms implicity provides an insight into the quality of the used ontologies and thus opens the way to a task-based evaluation of the Semantic Web. We have investigated this hypothesis by studying the lessons learnt about online ontologies when used to solve three tasks: ontology matching, folksonomy enrichment, and word sense disambiguation. Our analysis leads to a suit of conclusions about the status of the Semantic Web, which highlight a number of strengths and weaknesses of the semantic information available online and complement the findings of other analysis of the Semantic Web landscape

Análise florística e estrutural da vegetação arbórea em um sistema agroflorestal no Cerrado, em Dourados, MS

bitstream/item/66241/1/31279.pdfOrganizado por: Alberto Feiden, Milton Parron Padovan, Adalgiza Inês Campolim, Aurélio Vinícius Borsato, Ivo de Sá Motta, João Batista Catto, Tércio Jacques Fehlauer

Incidência de bicho-mineiro em diferentes cultivares de cafeeiro em sistema agroecológico.

bitstream/item/68482/1/061-Incidencia-de-bicho-mineiro-em-diferentes-cultivares-de-cafeeiro.pdfPublicado também no Cadernos de Agroecologia, v. 7, n. 2, 2012

Enhancement of Friction between Carbon Nanotubes: An Efficient Strategy to Strengthen Fibers

Interfacial friction plays a crucial role in the mechanical properties of carbon nanotube based fibers, composites, and devices. Here we use molecular dynamics simulation to investigate the pressure effect on the friction within carbon nanotube bundles. It reveals that the intertube frictional force can be increased by a factor of 1.5 ~ 4, depending on tube chirality and radius, when all tubes collapse above a critical pressure and when the bundle remains collapsed with unloading down to atmospheric pressure. Furthermore, the overall cross-sectional area also decreases significantly for the collapsed structure, making the bundle stronger. Our study suggests a new and efficient way to reinforce nanotube fibers, possibly stronger than carbon fibers, for usage at ambient conditions.Comment: revtex, 5 pages, accepted by ACS Nano 10 Dec 200

Chumbo e cádmio em frutos e folhas de erva-mate trazem riscos a saúde humana?

Resumo