DC-Prophet: Predicting Catastrophic Machine Failures in DataCenters

When will a server fail catastrophically in an industrial datacenter? Is it possible to forecast these failures so preventive actions can be taken to increase the reliability of a datacenter? To answer these questions, we have studied what are probably the largest, publicly available datacenter traces, containing more than 104 million events from 12,500 machines. Among these samples, we observe and categorize three types of machine failures, all of which are catastrophic and may lead to information loss, or even worse, reliability degradation of a datacenter. We further propose a two-stage framework-DC-Prophet-based on One-Class Support Vector Machine and Random Forest. DC-Prophet extracts surprising patterns and accurately predicts the next failure of a machine. Experimental results show that DC-Prophet achieves an AUC of 0.93 in predicting the next machine failure, and a F3-score of 0.88 (out of 1). On average, DC-Prophet outperforms other classical machine learning methods by 39.45% in F3-score.Comment: 13 pages, 5 figures, accepted by 2017 ECML PKD

Inelaticity in hadron-nucleus collisions from emulsion chamber studies

The inelasticity of hadron-carbon nucleus collisions in the energy region exceeding 100 TeV is estimated from the carbon-emulsion chamber data at Pamirs to be $= 0.65\pm 0.08$. When combined with the recently presented data on hadron-lead nucleus collisions taken at the same energy range it results in the $K\sim A^{0.086}$ mass number dependence of inelasticity. The evaluated partial inelasticity for secondary ($\nu > 1$) interactions, $K_{\nu >1} \simeq 0.2$, suggests that the second and higher interactions of the excited hadron inside the nucleus proceed with only slight energy losses.Comment: LaTeX file and 5 LaTeX files with figures, 11 pages altogether. Thoroughly rewritten and modified, one figure addded one removed. To be published in Phys. Rev.

Efeitos dos antibióticos rifampicina e cefotaxima no desenvolvimento de calos de maracuja-amarelo (Passiflora edulis f. Flavicarpa).

Este trabalho teve como objetivo verificar o efeito de antibióticos adicionados ao meio decultura ou em banho de imersão dos explantes no controle da contaminação e no desenvolvimento dos calos de maracujá-amarelo

Shrinkage and mechanical performance of geopolymeric mortars based on calcined Tunisian clay

Infrastructure rehabilitation represents a multitrillion dollar opportunity for the construction industry. Since the majority of the existent infrastructures are Portland cement concrete based this means that concrete infrastructure rehabilitation is a hot issue to be dealt with. Geopolymers are novel inorganic binders with high potential to replace Portland cement based ones. Geopolymerization is a complex chemical process evolving various aluminosilicate oxides with silicates under highly alkaline conditions, yielding polymeric units, similar to those of an aluminosilicate glass. So far very few studies in the geopolymer field have addressed the rehabilitation of deteriorated concrete structures. This paper discloses some results of an investigation concerning the development geopolymeric repair mortars based on a calcined Tunisian clay. The results show that Tunisian calcined clay based mortars have hydration products with typical geopolymeric phases. Results also show that the geopolymeric mortar shows a high unrestrained shrinkage behavior and that its modulus of elasticity is below the threshold required for this repair mortars

Mechanical performance of geopolymeric mortars based on tunisian calcined clay, fly ash and metakaolin

Infrastructure rehabilitation represents a multitrillion dollar opportunity for the construction industry. Since the majority of the existent infrastructures are Portland cement concrete based this means that concrete infrastructure rehabilitation is a hot issue to be dealt with. Geopolymers are novel inorganic binders with high potential to replace Portland cement based ones. So far very few studies in the geopolymer field have addressed the rehabilitation of deteriorated concrete structures. This paper discloses results of an investigation concerning the development geopolymeric repair mortars. The mortars are based on Tunisian clay coming from Medenine region, plus calcium hydroxide, sodium silicate and sodium hydroxide. Results show that the geopolymeric mortar has a high compressive strength and a lower unrestrained shrinkage performance as long as partial replacement by metakaolin is carried out. The results also show that Tunisian calcined clay based mortars have hydration products with typical geopolymeric phases

Modelação de organismos com crescimento logarítmico: aplicação às amonites *

This work refers to the development of modelling tools to create Ammonite shells in order to produce animated models for scientific dissemination and didactic purposes. In the approach here proposed we assume that the growth of those shells from an initial stage – the protoconch – can be interpreted as a succession of revolutions in turn of a central axis; thus the conch’s section will increase as a non-linear progression. So, we emphasise that the shape of many type of shells, e.g. gastropods and bivalves, is based on the equation of the logarithmic spiral deduced by R. Descartes. Pixels 3d (Pixels Digital Inc., 2005) is a TCL – scriptable modelling and animation software that allows extendable interapplication communication. Hence a standalone prototype (Shellia) with shell assignable parameters was produced and some of their issues and results will be presented here

Formação de calos a partir de hipocótilos de mamoeiro submetidos a diferentes concentrações de 2, 4-D e sacarose.

Este trabalho buscou verificar o efeito de diferentes concentrações de sacarose e de 2,4 D na formação e desenvolvimento de calos de mamão da variedade ?Tainung 1?

The space density distribution of galaxies in the absolute magnitude - rotation velocity plane: a volume-complete Tully-Fisher relation from CALIFA stellar kinematics

The space density distribution of galaxies in the absolute magnitude - rotation velocity plane: a volume-complete Tully-Fisher relation from CALIFA stellar kinematicsComment: Accepted to A&

Survey and characterization of corbelled dome architecture in Northwestern Portugal

The act of overlaying stones to build masonry structures is one of mankind’s most intuitive and resourceful achievements. Masonry buildings can be found all over the world, built with a wide diversity of materials and serving for all kind of purposes. In rural northwestern Portugal, in a granitic highland landscape of scarce resources, for centuries, local farmers used masonry in order to make the territory suitable for farming. In their effort to increase production and, by doing so, to improve their living conditions, a specific mountain agro-pastoral system was developed. Supported by communitarian labour, this system was based on terrace farming and temporary mountain plateau settlements, called brandas, composed of granite corbelled dome buildings. In spite of its perfect adaptation to the harsh local conditions, this heritage’s morphological and typological diversity and constructive inventiveness is endangered due to decades of rural exodus and, thus requiring urgent study and protection. The research project aims to study this heritage from morphological, typological and constructive points of view, with the objective of proposing guidelines towards its preservation. To achieve the established goals, a four stage based methodology was established. Literature review and fieldwork surveys were performed in the first stage, in order to identify possible case studies. On the second stage, an exhaustive geometrical survey and a case study analysis were undertaken and complemented with the local granite’s physical and mechanical characterization. The third stage aims to do an overall structural safety evaluation of the corbelled domes, based on numerical analysis. In the final stage, consolidation and preservation guidelines to safeguard this architectural heritage will be proposed. This paper presents the results of the first stage, along with a glimpse of the second stage.The authors wish to express their gratitude to the Municipality of Arcos de Valdevez, for all the support given, and to the Equipa de Sapadores Florestais do Gabinete Técnico Florestal do Município e da Associação Floresta Atlântica. The first and fifth authorswishto express theirgratitude to the Portuguese Science and Technology Foundation for the scholarshipsgranted (SFRH/BD/ 86704/2012 and SFRH/BD/112646/2015).This work was supported by FCT, within ISISE, project UID/ECI/04029/2013