Decision diagrams in machine learning: an empirical study on real-life credit-risk data.

Decision trees are a widely used knowledge representation in machine learning. However, one of their main drawbacks is the inherent replication of isomorphic subtrees, as a result of which the produced classifiers might become too large to be comprehensible by the human experts that have to validate them. Alternatively, decision diagrams, a generalization of decision trees taking on the form of a rooted, acyclic digraph instead of a tree, have occasionally been suggested as a potentially more compact representation. Their application in machine learning has nonetheless been criticized, because the theoretical size advantages of subgraph sharing did not always directly materialize in the relatively scarce reported experiments on real-world data. Therefore, in this paper, starting from a series of rule sets extracted from three real-life credit-scoring data sets, we will empirically assess to what extent decision diagrams are able to provide a compact visual description. Furthermore, we will investigate the practical impact of finding a good attribute ordering on the achieved size savings.Advantages; Classifiers; Credit scoring; Data; Decision; Decision diagrams; Decision trees; Empirical study; Knowledge; Learning; Real life; Representation; Size; Studies;

Elastomer Filled With Single-Wall Carbon Nanotubes

Experiments have shown that composites of a silicone elastomer with single-wall carbon nanotubes (SWNTs) are significantly stronger and stiffer than is the unfilled elastomer. The large strengthening and stiffening effect observed in these experiments stands in contrast to the much smaller strengthening effect observed in related prior efforts to reinforce epoxies with SWNTs and to reinforce a variety of polymers with multiple-wall carbon nanotubes (MWNTs). The relative largeness of the effect in the case of the silicone-elastomer/SWNT composites appears to be attributable to (1) a better match between the ductility of the fibers and the elasticity of the matrix and (2) the greater tensile strengths of SWNTs, relative to MWNTs. For the experiments, several composites were formulated by mixing various proportions of SWNTs and other filling materials into uncured RTV-560, which is a silicone adhesive commonly used in aerospace applications. Specimens of a standard "dog-bone" size and shape for tensile testing were made by casting the uncured elastomer/filler mixtures into molds, curing the elastomer, then pressing the specimens from a "cookie-cutter" die. The results of tensile tests of the specimens showed that small percentages of SWNT filler led to large increases in stiffness and tensile strength, and that these increases were greater than those afforded by other fillers. For example, the incorporation of SWNTs in a proportion of 1 percent increased the tensile strength by 44 percent and the modulus of elasticity (see figure) by 75 percent. However, the relative magnitudes of the increases decreased with increasing nanotube percentages because more nanotubes made the elastomer/nanotube composites more brittle. At an SWNT content of 10 percent, the tensile strength and modulus of elasticity were 125 percent and 562 percent, respectively, greater than the corresponding values for the unfilled elastomer

DNA Barcoding of the First Recorded American Burying Beetle, Nicrophorus americanus, in Clark County, Arkansas

The American Burying Beetle (ABB), Nicrophorus americanus, is a red-listed endangered species under the Endangered Species Act (16 U.S.C. 1531 et seq.). We serendipitously recorded 3 individuals of this species during a forensic study in the summer of 2013. These specimens represent the first known records for Clark County, AR and the southeastern-most record in the State since the extirpation of the species from the region in the late 1800’s. Two males and one female were collected, photographed, sexed and measured. One male specimen was deceased upon discovery. The remaining two individuals were released. The U.S. Fish and Wildlife Service (USFWS) was notified of the accidental catch and death of an endangered species as required and the specimen was awarded to Ouachita Baptist University for further study. The deceased specimen was used for DNA barcode sequence analysis. A 400bp section of the cytochrome c oxidase I (COI) gene was amplified using gene specific primers and then sequenced using Sanger sequencing methods. Sequence analysis revealed the collected beetle to be 98.5% identical to the ABB voucher sequence and was 86% similar to other Nicrophorus species. Taken together the DNA sequence analysis results and taxonomic identification both support the identification of our specimen

The tax-expenditure linkage in Korea

노트 : - IPD Tax Task Force- 30 March 2005 Task Policy Meetin

Avaliação do potencial produtivo da videira Niágara Rosada na Região de Pelotas.

O Objetivo do trabalho é avaliar a produção de videira ?Niágara Rosada? na região de Pelotas, com e sem a utilização da cobertura da parreiral com plástico transparente

Percutaneous Embolization of Congenital Portosystemic Venous Fistula in an Infant with Down Syndrome

Congenital intrahepatic portosystemic venous shunts are rare vascular malformations often associated with severe complications. We describe a term male infant with Down syndrome with high output heart failure secondary to a congenital arterial to portal venous fistula that was diagnosed by Doppler ultrasound. Percutaneous embolizations of the left hepatic vein, portal vein, and communicating fistulas were performed without complications, resulting in clinical improvement. A subsequent hepatic ultrasound demonstrated resolution of the pathologic fistulous communication and shunting effects

Purification of Carbon Nanotubes: Alternative Methods

Traditional carbon nanotube purification process involves nitric acid refluxing and cross flow filtration using surfactant TritonX. This is believed to result in damage to nanotubes and surfactant residue on nanotube surface. Alternative purification procedures involving solvent extraction, thermal zone refining and nitric acid refiuxing are used in the current study. The effect of duration and type of solvent to dissolve impurities including fullerenes and P ACs (polyaromatic compounds) are monitored by nuclear magnetic reasonance, high performance liquid chromatography, and thermogravimetric analysis. Thermal zone refining yielded sample areas rich in nanotubes as seen by scanning electric microscopy. Refluxing in boiling nitric acid seem to improve the nanotube content. Different procedural steps are needed to purify samples produced by laser process compared to arc process. These alternative methods of nanotube purification will be presented along with results from supporting analytical techniques