Query expansion using an immune-inspired biclustering algorithm

Query expansion is a technique utilized to improve the performance of information retrieval systems by automatically adding related terms to the initial query. These additional terms can be obtained from documents stored in a database. Usually, this task is performed by clustering the documents and then extracting representative terms from the clusters. Afterwards, a new search is performed in the whole database using the expanded set of terms. Recently, the authors have proposed an immune-inspired algorithm, namely BIC-aiNet, to perform biclustering of texts. Biclustering differs from standard clustering algorithms in the sense that the former can detect partial similarities in the attributes. The preliminary results indicated that our proposal is able to group similar texts effectively and the generated biclusters consistently presented relevant words to represent a category of texts. Motivated by this promising scenario, this paper better formalizes the proposal and investigates the usefulness of the whole methodology on larger datasets. The BIC-aiNet was applied to a set of documents aiming at identifying the set of relevant terms associated with each bicluster, giving rise to a query expansion tool. The obtained results were compared with those produced by two alternative proposals in the literature, and they indicate that these techniques tend to generate complementary results, as a consequence of the use of distinct similarity metrics.     

Fuzzy multivariate mean square error in equispaced pareto frontiers considering manufacturing process optimization problems

This paper proposes a combined approach using the normal boundary intersection (NBI) and multivariate mean square error (MMSE) that is an alternative approach to outperform the traditional NBI driving to an equispaced Pareto Frontier in a low-dimension space with a considerable reduction in the number of iterations. The method participating in the evolutionary stage of creating a uniformly spread Pareto Frontier for a nonlinear multi-objective problem is the NBI using normalized objective functions allied to MMSE. In sequence, the fuzzy MMSE approach is utilized to determine the optimal point of the multi-objective optimization. For sake of comparison, the performance of arc homotopy length, global criterion method, and weighted sums were explored. To illustrate this proposal, a multivariate case of AISI H13 hardened steel-turning process is used. Experimental results indicate that the solution found by NBI-MMSE approach is a more appropriate Pareto frontier that surpassed all the competitors and also provides the best-compromised solution to set the machine input parameters. Further, this algorithm was also tested in benchmark functions to confirm the NBI-MMSE efficiency.

     

Use of a fuzzy logic scheduler to improve quality of service on cellular networks

Telecommunication Systems - An efficient and fair packet scheduler is very important to guaranty the cellular network quality of service (QoS). In general, classic packet schedulers follow static...     

Phosphorus and potassium cycling in a long-term no-till integrated soybean-beef cattle production system under different grazing intensities insubtropics

Long-term integrated crop-livestock system enables constant and more efficient nutrient cycling because animal, pasture and crop residues release nutrients at different rates. Therefore, appropriate management of these systems is needed to maximize benefits from nutrient cycling. The objective of this study was to evaluate how grazing intensity affected the release rates of phosphorus (P) and potassium (K) in pasture, dung and soybean residues in a no-till long-term integrated crop-livestock system. The experiment was established in 2001 on a clayey Oxisol after soybean harvest. Treatments consisted of pasture with sward heights maintained at 1020, 30 and 40 cm by different cattle stocking rates and a non-grazed (NG) treatment. Decomposition and release rates of nutrients in the pasture and dung were determined using litter bags, which were installed at soybean seeding and pasture seeding during two pasture-crop cycles (2009–2011). Lighter grazing intensities resulted in greater P release rate from pasture and dung residues. Pasture and dung residues released K at a very high rate and were not influenced by grazing intensity. The P and K released from soybean residue were not affected by grazing intensity; however, decomposition of soybean leaves was greater than of stems. Greatest rates of total P and K released were from pasture and dung residues under lighter grazing intensities and in the NG areas. Large amounts of P (~25 kg ha^?1) and K (~130–180 kg ha^?1) were cycled in a complete soybean-beef cattle integrated system and must be considered in the fertilization management.     

A Microstructurally Based Model for Recrystallization in Dual-Phase Steels

Metallurgical and Materials Transactions A - Adjusting and predicting the ferrite recrystallization kinetics of cold-rolled Advanced High-Strength Steels during annealing is necessary to control...     

Comparison of ductile material erosion models combining cutting and deformation components of wear

ABSTRACT

Herein we compare seven models of erosion of ductile materials, considering various combinations including cutting and deformation components of wear. The models were fit to three independent sets of experimental results to verify the quality of fitting based upon the coefficient of determination. The results were discussed especially in terms of the friction component, the adjustment of which could lead to better fitting.     

Thermoresistive and thermoelectric properties of coplanar cellulose-MWCNTs buckypaper

Thermoresistive sensors are based on the change in electrical resistance with temperature variation, are easily read, and have a simple design but require external power for their operation. Thermoelectric devices (TDs) based on the Seebeck effect directly convert heat into electrical power without any moving parts, generating voltages from the temperature difference established between the ends of a solid-state material. In recent years, several thermoresistors and TDs have been manufactured with conductive films based on carbon nanotubes (CNTs), i.e., with buckypaper (BP), because they provide lightweight, flexible, and sensitive devices. Nevertheless, the electrical resistance and thermoelectric properties of CNTs are affected when they are randomly assembled to form a BP. Then, this study investigated the thermoresistive and thermoelectric properties of a coplanar BP with an active area of 1.0 cm². Morphological characterization was performed by scanning electron microscopy and showed bundles of multiwalled CNTs agglomerated on the surface but also impregnated into cellulose fibers. BP-based thermoresistive sensor had a maximum sensitivity of ??10.05% at 322 K. Moreover, the thermoelectric configuration presented a maximum thermovoltage and thermoelectric power of ??1.2 mV and ??0.09 mV/K, respectively. These results suggest that this coplanar BP can be easily applied in thermal sensors and thermoelectric device concepts.

     

Water Content in Self-Etching Primers Affects Their Aggressiveness and Strength of Bonding to Ground Enamel

In this study the influence of water concentration in self-etching (SE) primers on their aggressiveness and bond strength to ground enamel was investigated. Five experimental primers with 0, 5, 10, 20, or 40 wt% of water were formulated, using Clearfil SE Bond® (CSEB) as a commercial reference. Primers were applied to bovine incisors following application of bonding resin and composite restoration. Bond strength was evaluated through shear testing and data were statistically analyzed (5%). The etching aggressiveness was evaluated by SEM. Water concentration significantly affected bond strength and etching aggressiveness. The highest bond strength value (MPa) was found for the primer containing 20% of water (24.7), followed by CSEB (23.8). Groups containing 5% (20.5) and 10% (20.2) of water showed an intermediate performance, while the lowest values were observed for the 0% (17.3) and 40% (16.7) groups. SEM analysis showed increasing aggressiveness for increased water content.