University of Atacama or UDA is a university in Chile. It is part of the Chilean Traditional Universities. The university is located in Copiapó, in the Third Region, Atacama.The University was created in 1981, as a fusion of the old Mines School of Copiapo, founded in 1857 and very prestigious in the minerals industries, this School was integrated in 1947 in early foundated Universidad Técnica del Estado, being the new U.T.E. until 1981 the most important Chilean university in applied science and the Normal School of Copiapó, founded in 1905. UDA has four Faculties: Humanities and Education, Law, Engineering, and Natural science, as well as five institutes: the Technological Institute, the Language Institute, the Center for Technical Education , the Institute for Scientific and Technological Research , and INSAMIN.The University of Atacama houses several historical monuments on campus, including the first steam engine to traverse Chile, between Copiapó and the port city of Caldera, in 1851. Wikipedia.
Guzman-Ramirez L.,European Southern Observatory |
Guzman-Ramirez L.,University of Manchester |
Lagadec E.,Cornell University |
Jones D.,European Southern Observatory |
And 3 more authors.
Monthly Notices of the Royal Astronomical Society | Year: 2014
Polycyclic aromatic hydrocarbons (PAHs) have been observed in O-rich planetary nebulae towards the Galactic bulge. This combination of oxygen-rich and carbon-rich material, known as dual-dust or mixed chemistry, is not expected to be seen around such objects. We recently proposed that PAHs could be formed from the photodissociation of CO in dense tori. In this work, using VISIR/VLT, we spatially resolved the emission of the PAH bands and ionized emission from the [S IV] line, confirming the presence of dense central tori in all the observed O-rich objects. Furthermore, we show that for most of the objects, PAHs are located at the outer edge of these dense/compact tori, while the ionized material is mostly present in the inner parts of these tori, consistent with our hypothesis for the formation of PAHs in these systems. The presence of a dense torus has been strongly associated with the action of a central binary star and, as such, the rich chemistry seen in these regions may also be related to the formation of exoplanets in post-common-envelope binary systems. © 2014 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society.
Mery D.,University of Chile |
Mondragon G.,University of Chile |
Riffo V.,University of Chile |
Zuccar I.,University of Atacama
Insight: Non-Destructive Testing and Condition Monitoring | Year: 2013
In order to reduce the security risk of a commercial aircraft, passengers are not allowed to take certain items in carry-on baggage. For this reason, human operators are trained to detect prohibited items using a manually controlled baggage screening process. In this paper, we propose the use of a method based on multiple X-ray views to detect some regular prohibited items with very defined shapes and sizes. The method consists of two steps: 'structure estimation', to obtain a geometric model of the multiple views from the object to be inspected (baggage); and 'parts detection', to detect the parts of interest (prohibited items). The geometric model is estimated using a structure from a motion algorithm. The detection of the parts of interest is performed by an ad-hoc segmentation algorithm (object dependent) followed by a general tracking algorithm based on geometric and appearance constraints. In order to illustrate the effectiveness of the proposed method, experimental results on detecting regular objects - razor blades and guns - are shown yielding promising results. © 2013 Publishing Technology.
News Article | November 3, 2015
Looking at pictures of Chile's Atacama Desert right now, you would never know it's one of the driest places on the planet. Normally the landscape is parched and arid. But this year it's covered in flowers—mauves, reds, yellows, whites—creating a stunning and unusual spectacle. Heavy rains prepared the ground back in March. The Atacama region saw almost an inch of rain in one day—the equivalent of 14 years of rain in 24 hours. "This year has been particularly special, because the amount of rainfall has made this perhaps the most spectacular of the past 40 or 50 years," Raul Cespedes, a desert scientist at the University of Atacama, told AFP. According to AFP, the flowers include violet-and-white Chilean bell flowers, countryside sighs (Nolana paradoxa), red lion claws (Bomarea ovallei), and yellow Rhodophiala rhodolirion. Because of the intensity of the storms, there were two flowerings: in the winter and now again in the Chilean spring. "Two flowerings a year is very unusual in the most arid desert in the world, and that's something we've been able to enjoy this spring, along with people from all over the world. There's a lot of interest in seeing it," Daniel Diaz, director of the National Tourism Service in Atacama, told AFP. Meteorologists blame El Niño for the extreme rainfall in Atacama and warn of worse to come as that weather pattern intensifies. But for now, the event is a boon for tourism and a something to marvel at: flowers where flowers don't normally grow.
Santander M.,Federal University of Rio Grande do Sul |
Santander M.,University of Atacama |
Rodrigues R.T.,Federal University of Rio Grande do Sul |
Rubio J.,Federal University of Rio Grande do Sul
Colloids and Surfaces A: Physicochemical and Engineering Aspects | Year: 2011
This work presents results of a rapid emulsified oil (petroleum) removal from water by flocculation followed by flotation in a modified jet (Jameson) cell (MJC). The modification is such that the downcomer was sealed at the bottom (by a concentric blind-end tube) to allow floated particles to enter immediately into the frothy phase after the capture of the oily flocs by the bubbles. Also, a packed bed (crowder) was placed at the upper part of the concentric tube to stabilize the froth and facilitate the rise of the oil floc/bubble aggregates. The work was divided into two parts: a detailed laboratory study (1.3m3/h) and a pilot plant trial in an offshore platform. Parameters studied were flocculation (type and concentration of polymer), oil concentration, oil droplets size distribution and flotation cell design. Results of laboratory studies showed mean separation efficiencies of the order of 80% when used as a conventional jet cell (CJC) with feed emulsions (droplets size of about 20μm) ranged between 100 and 400mg/L petroleum concentration. The oil removal increased up to 85% in the MJC. These studies allowed optimizing the design and process parameters: chemical, physico-chemical and operating. A MJC (5m3/h) was then projected, built and installed in an offshore platform, after the oil extraction-production point. At optimal conditions, in a single flotation stage, discharges varied between 20 and 30mg/L oil concentration or 81% removal at 24.7m3/hm2 loading capacity. Because this jet cell operates with a high air hold-up, it presented a very good efficiency (capture of oil droplets by bubbles) at low residence time (high-rate separation) and showed to be simple, compact and easy to operate. It is believed that the MJC has a great potential for treating polluted oily high flow wastewaters, at high separation rate. Results and mechanisms involved are discussed in terms of interfacial phenomena and design factors. © 2011 Elsevier B.V.
Palacios J.,University of Atacama |
Sanchez M.,University of Concepción
Transactions of the Institutions of Mining and Metallurgy, Section C: Mineral Processing and Extractive Metallurgy | Year: 2011
Copper production from sulphide minerals generates massive amounts of slag as final waste of the pyrometallurgical processes. Dumping the slag nearby the smelter plant has been the common practice and, currently it is produced in a proportion of 2.2 ton of slag per ton of blister copper and is granulated to facilitate the transportation and final disposal. Thus, it is relevant to improve sustainability by recycling this waste to minimise the environmental impact generated during pyrometallurgical treatment of copper sulphides concentrates. Laboratory tests were run in order to concentrate and separate metals and materials for obtaining results that could be scaled up to pilot and industrial level. The results of pyrometallurgical and hydrometallurgical experiments are presented in order to show the importance of the oxidation of the slag at high temperatures that could liberate those metals molecularly entrapped during processing sulphide concentrate in the smelter plant. Therefore, the present work shows experimental work done in Chile in order to add value to this waste by recovering contained metals and materials such as copper, molybdenum, and iron and silica, with iron and silica being more than half of the total content of the slag, which has an important effect on the volume of the stocked material. © 2011 Institute of Materials, Minerals and Mining and The AusIMM.
Rivera J.D.D.,University of Atacama
Atmospheric Research | Year: 2011
Fog water collectors (FWC) can provide water to arid zones with persistent advection and orographic fog. A key feature of any FWC is the mesh used to capture fog droplets. Two relevant mesh characteristics are its shade coefficient and the characteristics of the fibers used to weave or knit the mesh. This paper develops a simple superposition model to analyze the effect of these factors on the Aerodynamic Collection Efficiency (ACE) of FWCs. Due to the simplicity of the model it cannot be directly applied to actual FWC meshes, and serve only for guidance on the order of magnitude of the optimum shade coefficient and the corresponding ACE. The model shows that there is a maximum ACE of the order of 20-24.5% for shade coefficients between 0.5 and 0.6, for the particular mesh simulated. Aerodynamic collection efficiency can be increased by making the FWC concave and improving the aerodynamics of the mesh fibers. © 2011 Elsevier B.V.
Pirani S.,Lund University |
Turrini D.,National institute for astrophysics |
Turrini D.,University of Atacama
Icarus | Year: 2016
Asteroid 4 Vesta is the only currently identified asteroid for which we possess samples in the form of meteorites. These meteorites revealed us that Vesta is a differentiated body and that its differentiation produced a relatively thin basaltic crust that survived intact over its entire collisional history. The survival of the vestan basaltic crust has long been identified as a pivotal constraint in the study of the evolution of the asteroid belt and the Solar System but, while we possess a reasonably good picture of the effects of the last 4 Ga on such a crust, little is known about the effects of earlier events like the Late Heavy Bombardment. In this work we address this gap in our knowledge by simulating the Late Heavy Bombardment on Vesta in the different dynamical scenarios proposed for the migration of the giant planets in the broad framework of the Nice Model. The results of the simulations allowed us to assess the collisional history of the asteroid during the Late Heavy Bombardment in terms of produced crater population, surface saturation, mass loss and mass gain of Vesta and number of energetic or catastrophic impacts. Our results reveal that planet-planet scattering is a dynamically favorable migration mechanism for the survival of Vesta and its crust. The number of impacts of asteroids larger than about 1 km in diameter estimated as due to the LHB is 31 ± 5, i.e. about 5 times larger than the number of impacts that would have occurred in an unperturbed main belt in the same time interval. The contribution of a possible extended belt to the collisional evolution of Vesta during the LHB is quite limited and can be quantified in 2 ± 1 impacts of asteroids with diameter greater than or equal to 1 km. The chance of energetic and catastrophic impacts is less than 10% and is compatible with the absence of giant craters dated back to 4 Ga ago and with the survival of the asteroid during the Late Heavy Bombardment. The mass loss caused by the bombardment translates in the erosion of 3. -5 m of the crust, consistently with the global survival of the basaltic crust of Vesta confirmed by the Dawn mission. Our analysis revealed that the contribution of the LHB to the cratering of Vesta' surface is not significant and is actually erased by the crater population produced by the following 4 Ga of collisional evolution of the asteroid, in agreement with the data provided by the Dawn mission. © 2016 Elsevier Inc.
Carrizo D.,University of Atacama
Revista Facultad de Ingenieria | Year: 2013
The software requirements elicitation from stakeholders has been stated as a key activity influencing strongly on quality of specified requirements and, therefore, of the final development product. For this raison, is undoubtly the necessity to dispose clear guidelines to drive the interrelationship with the owners of the domain information and the needs that require solutions. This work focuses on the model of the elicitation considering the influence of the contextual agents of the process, such as: elicitor, who drive the activity; informant, who possess the relevant information; problem domain, characteristics of the problematic to tackle; and process, characteristics and restrictions of the activity itself. The article analyses the dynamic that relates these factors to select the technique to use in each elicitation session. Finally, the work contributes with a time model of the process and with the representation of the main casuistic of elicitation process.
Thomas J.C.R.,University of Atacama
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2011
This project shows the development of a new clustering algorithm, based on k-means, which faces its problems with clusters of differences variances. This new algorithm uses a line segment as prototype which captures the axis that presents the biggest variance of the cluster. The line segment adjusts iteratively its long and direction as the data are classified. To perform the classification, a border region that determines approximately the limit on the cluster is built based on geometric model, which depends on the central line segment. The data are classified later according to their proximity to the different border regions. The process is repeated until the parameters of the all border regions associated with each cluster remain constant. © 2011 Springer-Verlag.
Influential contextual attributes in the requirements elicitation process: A comprehensive literature review [Atributos contextuales influyentes en el proceso de educción de requisitos: Una exhaustiva revisión de literatura]
Moreno D.C.,University of Atacama
Ingeniare | Year: 2015
The requirements elicitation captures relevant information to the shaping of software requirements by using several techniques. However, the effectiveness of the process depends on the context in which it occurs. This article aims to reveal the attributes of the context influencing the elicitation process. For this purpose, a systematic and non-systematic review of the scientific literature was conducted in order to determine which are these attributes. The result of this review yielded 118 attributes that were grouped into 27 generic attributes corresponding to 5 factors: the eductor, the informant, the problem domain, the solution domain and the process itself. This study helps to guide future empirical researches on requirements elicitation pointing out possible experimental factors to consider. © 2015, Universidad de Tarapaca. All rights reserved.