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The environmental problem generated by the poor used oil discard mechanisms at the present time in Colombia has enable the establishment of business focused on the proper collection and disposal of waste in some of Colombia's major cities; however, this mechanisms still do no guarantee that these companies provide full coverage. The city of Pereira has a high number of oil generating agents (such as Lubrication Centers, Service Centers, Repair shops, among others), which requires the creation of a proper oil waste recovery and disposal system in order to benefit the environment and the citizens. This paper presents the creation of a reverse logistics network associated with the proper used oil collection in the city of Pereira. To build the model it was necessary to identify the residue generators points, the distances between each of the nodes and the logistics variable costs evaluating two types of tanker trucks. The situation was modeled as a Capacited Vehicle Routing Problem (CVRP), which was solved by implementing the route-first cluster-second principle in vehicle routing, a two phase heuristic. The first phase is solved by using the Savings Algorithm, while the second phase is solved by using the Clustering Algorithm. Further on, both algorithms are programmed in MATLAB, where the solution determines the sub-routes integrating the reverse logistics network with the order in which each vehicle should visit the different used oil generating points. [ABSTRACT FROM AUTHOR]

This article presents the results of a research conducted in the field, where the conditions in the mobility of people with physical-motor disabilities in the metropolitan area of Bucaramanga, Colombia are analyzed. The methodology was based on the identification and classification of public transport systems (conventional bus, taxis and Metrolínea), the assessment of the appropriate infrastructure for the mobility of the population under study and the processing of data obtained through a stated preference survey applied to 100 people with physical limitations in the city. It is concluded that there is not any transportation system that unifies all the advantages when mobilising: comfort, coverage, economy and ease of access; situation that might allow some improvement in the quality of life of such a population. [ABSTRACT FROM AUTHOR]

In this paper different kinds of Solid Oxide Fuel Cells (SOFC) and their operating principles are presented. In terms of internal structure, SOFC can be classified into three categories: dual-chamber, single-chamber and no-chamber cells. Electrochemical performance is compared based on information available in the literature and advantages and disadvantages are established. Typical values of maximum power density (Pmax) and current density at Pmax are respectively: ∼ 1000 mW/cm²and ∼ 2000 mA/cm² for dual-chamber cells, ∼ 336 mW/cm² and ∼ 770 mA/cm² for singlechamber cells, and ∼ 210 mW/cm² and ∼ 440 mA/cm² for no-chamber cells. Although the electrochemical performance of the single- and no-chamber cells is lower than the dual-chamber cells, the operating advantages given are enough to consider them as viable alternative designs. Finally, are presented preliminary results of a new design of a no-chamber cell with a burner of porous media coupled with the fuel cell. [ABSTRACT FROM AUTHOR]

Global support radial base functions are effective in eliminating impulsive noise in non-linear processing. This paper introduces an interpolation technique which efficiently reduces image impulsive noise by means of an interpolant obtained through radial base functions. These functions have been used in a research project designed to develop a system for the recovery of images of Amazonian aquatic resources. This technique starts with the tagging by interpolation of noisy image pixels. Thus, a value of reconstruction for the noisy pixels is generated using neighboring pixels. The results obtained with this technique have proved comparable and often better than those obtained with previously known techniques. According to results analysis, this technique can be successfully applied on images with high noise levels. The results are low error in noisy pixel reconstruction and better visual quality. [ABSTRACT FROM AUTHOR]

In Information Retrieval Systems, Image Retrieval Systems are located; they allow generating searching and storing processes of resources through coincidences by key words or other real-time methods. This type of systems can use visual content of images (color, texture, and brightness) as indices. In addition, these systems combine different attributes to improve the processes of classification and relevance of the searching process results known as "Information Quality." This paper presents the modeling of a Image Retrieval System which combines attributes of the contentbased retrieval such as color, texture, and shape, with the Information Quality-based retrieval as updating portability and relevance frequency in the context of Digital Image Collection of Aquatic Amazon Ecosystems of Universidad del Amazonia CAPREA Research Group. [ABSTRACT FROM AUTHOR]

This article presents a compilation of the researches carried on the image recovery from web digital collections, based upon their contents and data quality management. Using this state-of-the-art study as a support, the article presents a methodological proposal to design and implement a system prototype in image recovery that uses these two search techniques; and finally the article presents the progress achieved in developing this proposal. [ABSTRACT FROM AUTHOR]

In this paper we present a method that permits the reduction of redundant information in range images using radial base functions and we indicate how these functions permit a continuous surface without holes or superposition when the images are integrated in a common system of coordinates. [ABSTRACT FROM AUTHOR]

Background and objective. Complications related to implant-based breast surgery are a potential safety issue due to its high incidence. Implant displacement is one of these complications that has been associated to frequent revision surgery. However, there is a lack of information about the characteristics and epidemiology of this condition. The aim of this study is to research in the scientific literature and propose a displacement classification. Methods. A literature review was done by using the keywords: Implant displacement, complications and breast implants, looking for publications about complications in breast surgery including implant displacement and the associated factors. Results. We found 186 publications of which 8 were included, with a total of 29.917 patients, age ranged from 14 to 77 and a follow up time from 0.1 to 34 years; 97.55% were silicone implants, 1% saline and 1% with no information. The smooth surface was used in 19.01% and textured in 79.63%. Subglandular approach was used from 5.7% to 73.3% of the cases, subpectoral from 5.4% to 80%, subfascial plane was used in 725 subjects in 1 study, and dual plane was used in 2 studies with 16.7% and 56.6%. Implant size was reported from 50 up to 800 cc. The reported displacement was between 0.3 up to 16.6% with a mean of 5.26% Conclusions. There is heterogeneity in the diagnosis and the reported outcomes, and a lack of a standard definition and diagnosis of the displacement. Implant displacement has been accused of being one of the first causes for revision in breast surgery, however, there is a lack of clinical studies that estimate the frequency of presentation and the related factors. A classification tool to assess the displacement is critical to standardize the outcomes and improve the quality of the studies. [ABSTRACT FROM AUTHOR]

Today, thanks to global positioning systems and mobile devices equipped with sensors, it is possible to capture information about the trajectory followed by moving objects such as persons, animals, and vehicles, among others. In this paper we analyze, in particular, the trajectories followed by moving objects on a predefined route, as in the case of a public transport system, in which vehicles should travel by a predetermined route. We present a case study where this type of trajectories are incorporated as a subject of analysis in a data warehouse. [ABSTRACT FROM AUTHOR]

Introduction. Waste Waters from the Dairy industries are highly loaded with organic matter (DQO- Chemical Oxygen Demand in Spanish- and fat). These pollutants have a considerable impact on the environment, especially on water. Electrocoagulation is a process that has being developed recently and is an alternative for treating waste waters from the dairy industries, offering advantages in comparison to the traditional technologies. Objective. To calculate the costs of implementing and operating electrocoagulation in a dairy industry, and comparing them with those from chemical coagulation. Materials and methods. The waste water from a dairy industry was treated by using electrocoagulation, using a bach process in order to find better conditions to remove its DQO and fat pollutants. Later, the waters were treated continuously, according to the response variables measured (percentages of removal of DQO, oils and fat), with these results. The process was escalated and the costs of implementation and operation were compared to those from chemical coagulation. Results. The operative costs of electrocoagulation are 80,75% of the operative costs of chemical electrocoagulation, and the implementation costs of electrocoagulation are half the costs of chemical electrocoagulation. Conclusion. Electrocoagulation shows itself as an efficient treatment both technical and economically, for removing pollutants from waste water in dairy industries. [ABSTRACT FROM AUTHOR]