234 research outputs found
Analysis of infrared optical polishing effluents and reduction of COD and TSS levels by ultrafiltration and coagulation/flocculation
Samples of polishing effluent produced during infrared optics manufacture were analyzed. Their particle size, composition, Zeta potential, chemical oxygen demand (COD), total suspended solids (TSS), and settleable solids were determined. Feasibility of treatment methods such as ultrafiltration (UF) and coagulation/flocculation was investigated to reduce both COD and TSS. It was found that effluents consisted of a suspension of micro- and nanoparticles. Effluent particle size distribution reflected the removal rate of the originating polishing process. Their composition was primarily germanium and other polished substrates as well as polishing abrasives. The effluent Zeta potential was highly negative and prevented particle settling. COD of all specimens was very high, which prevented sewage discharge. Laboratory-scale trials using UF showed substantial COD abatement of up to 74.1%. TSS was reduced to zero after UF. Comparable coagulation/flocculation COD abatement was demonstrated for the highest COD sample
Data fusion strategy for precise vehicle location for intelligent self-aware maintenance systems
Abstract— Nowadays careful measurement applications are
handed over to Wired and Wireless Sensor Network. Taking
the scenario of train location as an example, this would lead to
an increase in uncertainty about position related to sensors
with long acquisition times like Balises, RFID and
Transponders along the track. We take into account the data
without any synchronization protocols, for increase the
accuracy and reduce the uncertainty after the data fusion
algorithms. The case studies, we have analysed, derived from
the needs of the project partners: train localization, head of an
auger in the drilling sector localization and the location of
containers of radioactive material waste in a reprocessing
nuclear plant. They have the necessity to plan the maintenance
operations of their infrastructure basing through architecture
that taking input from the sensors, which are localization and
diagnosis, maps and cost, to optimize the cost effectiveness and
reduce the time of operation
Integration of cost-risk assessment of denial of service within an intelligent maintenance system
As organisations become richer in data the function of asset management will have to increasingly use intelligent systems to control condition monitoring systems and organise maintenance. In the future the UK rail industry is anticipating having to optimize capacity by running trains closer to each other. In this situation maintenance becomes extremely problematic as within such a high-performance network a relatively minor fault will impact more trains and passengers; such denial of service causes reputational damage for the industry and causes fines to be levied against the infrastructure owner, Network Rail.
Intelligent systems used to control condition monitoring systems will need to optimize for several factors; optimization for minimizing denial of service will be one such factor. With schedules anticipated to be increasingly complicated detailed estimation methods will be extremely difficult to implement. Cost prediction of maintenance activities tend to be expert driven and require extensive details, making automation of such an activity difficult. Therefore a stochastic process will be needed to approach the problem of predicting the denial of service arising from any required maintenance. Good uncertainty modelling will help to increase the confidence of estimates.
This paper seeks to detail the challenges that the UK Railway industry face with regards to cost modelling of maintenance activities and outline an example of a suitable cost model for quantifying cost uncertainty. The proposed uncertainty quantification is based on historical cost data and interpretation of its statistical distributions. These estimates are then integrated in a cost model to obtain accurate uncertainty measurements of outputs through Monte-Carlo simulation methods. An additional criteria of the model was that it be suitable for integration into an existing prototype integrated intelligent maintenance system. It is anticipated that applying an integrated maintenance management system will apply significant downward pressure on maintenance budgets and reduce denial of service. Accurate cost estimation is therefore of great importance if anticipated cost efficiencies are to be achieved. While the rail industry has been the focus of this work, other industries have been considered and it is anticipated that the approach will be applicable to many other organisations across several asset management intensive industrie
Precise vehicle location as a fundamental parameter for intelligent selfaware rail-track maintenance systems
The rail industry in the UK is undergoing substantial changes in response to a modernisation vision for 2040. Development and implementation of these will lead to a highly automated and safe railway. Real-time regulation of traffic will optimise the performance of the network, with trains running in succession within an adjacent movable safety zone. Critically, maintenance will use intelligent trainborne and track-based systems. These will provide accurate and timely information for condition based intervention at precise track locations, reducing possession downtime and minimising the presence of workers in operating railways. Clearly, precise knowledge of trains’ real-time location is of paramount importance.
The positional accuracy demand of the future railway is less than 2m. A critical consideration of this requirement is the capability to resolve train occupancy in adjacent tracks, with the highest degree of confidence. A finer resolution is required for locating faults such as damage or missing parts, precisely.
Location of trains currently relies on track signalling technology. However, these systems mostly provide an indication of the presence of trains within discrete track sections. The standard Global Navigation Satellite Systems (GNSS), cannot precisely and reliably resolve location as required either.
Within the context of the needs of the future railway, state of the art location technologies and systems were reviewed and critiqued. It was found that no current technology is able to resolve location as required. Uncertainty is a significant factor. A new integrated approach employing complimentary technologies and more efficient data fusion process, can potentially offer a more accurate and robust solution. Data fusion architectures enabling intelligent self-aware rail-track maintenance systems are proposed
An intelligent framework and prototype for autonomous maintenance planning in the rail industry
This paper details the development of the AUTONOM project, a project that aims to provide an enterprise system tailored to the planning needs of the rail industry. AUTONOM extends research in novel sensing, scheduling, and decision-making strategies customised for the automated planning of maintenance activities within the rail industry. This paper sets out a framework and software prototype and details the current progress of the project. In the continuation of the AUTONOM project it is anticipated that the combination of techniques brought together in this work will be capable of addressing a wider range of problem types, offered by Network rail and organisations in different industries
The liquid city in the strategy of the snail. Dismantling the architectural and ideological spiral of the postmodern city
En este ensayo, el director Sergio Cabrera nos retrotrae a la génesis de su obra cinematográfica La estrategia del caracol. Nos muestra las dificultades de producción que una idea poética basada en un hecho real (unos malvivientes, que iban a ser desalojados, se largaron, con la propia casa, antes que llegara el juez) tuvo que afrontar con los recursos estéticos de principios de la década de los noventa; el origen mitológico y vital del proyecto (la estancia del propio director en China durante la Revolución Cultural); y, por último, la utopía revolucionaria que enarbola la cinta, recayente en los grupos subalternos que, con desparpajo y creatividad política, se confrontan a los grandes capitalistas. Del caracol, sólo que su carcasa, dispuesta a ser llenada de betón y vaciada con sueños.
In this essay, the director Sergio Cabrera takes us back to the genesis of his cinematographic work The Strategy of the Snail. It shows us the difficulties of production that a poetic idea based on a real event (some crooks, that were going to be evicted, they left, with the own house, before the judge arrived) had to face with the aesthetic resources of principles of the nineties decade; the mythological and vital origin of the project (the director's stay in China during the Cultural Revolution); and, finally, the revolutionary utopia that hoists the film, recalling the subaltern groups that, with self-confidence and political creativity, confront the great capitalists. Of the snail, only that its shell, ready to be filled with cement and emptied with dreams
Nivel de conocimiento de la antibioticoterapia y la actitud en la prescripción de antibióticos en alumnos de la clínica estomatológica de una universidad privada
Objetivo: Determinar el nivel de conocimiento sobre antibióticoterapia y la actitud en la prescripción de antibióticos en odontología en alumnos de la facultad de estomatología de una universidad privada en el año 2018.
Materiales y métodos: El estudio tuvo un diseño metodológico descriptivo, prospectivo, transversal y observacional, fue de enfoque cuantitativo.Objective: To determine the level of knowledge about antibiotic therapy and the attitude in the prescription of antibiotics in dentistry in students of the faculty of Stomatology of a private university in the year 2018.
Materials and methods: the study had a descriptive methodological design, prospective, transversal and observational, was of quantitative focu
Influencia de la calidad de servicios en la satisfacción de los pacientes del Hospital de Tingo María, Leoncio Prado 2022
El objetivo de esta investigación fue determinar la influencia de la calidad de
servicio en la satisfacción del Hospital de Tingo María, 2022. La metodología fue
de enfoque cuantitativo, tipo básica, diseño no experimental y nivel correlacional
causal. Asi mismo la población estuvo conformada por 38,864 pacientes por el
Seguro Integral Social (SIS) y la muestra fueron 87 sufridos. La técnica fue una
encuesta y el instrumento un cuestionario de escala Likert con 62 interrogantes.
Obteniendo como resultados que la mayoría de los encuestados (74.7%)
consideran que la calidad de servicio se encuentra en un nivel regular; mientras el
25.3% afirma que el nivel de bueno. Por otra parte, la mayoría de los encuestados
(57.5%) presenta un nivel de satisfacción buena; mientras que el 42.5% de ellos se
encuentran en un nivel regular. Concluyendo que, la calidad de servicio se asocia
en la satisfacción del paciente en el Hospital de Tingo María 2022; ya que tiene una
influencia de r = 0.680 y una significancia de 0.000
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