A Discussion of Thin Client Technology for Computer Labs

Computer literacy is not negotiable for any professional in an increasingly computerised environment. Educational institutions should be equipped to provide this new basic training for modern life. Accordingly, computer labs are an essential medium for education in almost any field. Computer labs are one of the most popular IT infrastructures for technical training in primary and secondary schools, universities and other educational institutions all over the world. Unfortunately, a computer lab is expensive, in terms of both initial purchase and annual maintenance costs, and especially when we want to run the latest software. Hence, research efforts addressing computer lab efficiency, performance or cost reduction would have a worldwide repercussion. In response to this concern, this paper presents a survey on thin client technology for computer labs in educational environments. Besides setting out the advantages and drawbacks of this technology, we aim to refute false prejudices against thin clients, identifying a set of educational scenarios where thin clients are a better choice and others requiring traditional solutions

First-principles study of lithium-doped carbon clathrates under pressure

We present a theoretical study on the behavior under pressure of the two hypothetical C$_{46}$ and Li$_8$C$_{46}$ type-I carbon clathrates in order to bring new informations concerning their synthesis. Using \textit{ab initio} calculations, we have explored the energetic and structural properties under pressure of these two carbon based cage-like materials. These low-density meta-stable phases show large negative pressure transitions compared to diamond which represent a serious obstacle for their synthesis. However, we evidence that a minimum energy barrier can be reached close to 40 GPa, suggesting that the synthesis of the Li-clathrate under extreme conditions of pressure and temperature may be possible. Electronic band structure with related density of states behavior under pressure as well as the dependence of the active Raman modes with pressure are also examined

Quark-Monopole Potentials from Supersymmetric SL(3,R) Deformed IIB Supergravity

We recompute the quark-monopole potential from supersymmetric SL(3,R) deformation of IIB supergravity background dual to deformed Coulomb branch flow of the N=4 super Yang-Mills theory. The marginal deformations strengthen the Coulombic attraction between quarks and monopoles.Comment: 12pp; the discussions on (2.8) correcte

E-Learning aplicado a la cooperacion como herramienta educativa en la motivacion de profesores y alumnos.

Las tecnologías en general, y en especial las centradas en la información y las comunicaciones (TIC), están rompiendo barreras en el escenario social actual. Su dominio se hace indispensable para cualquier profesional, y en la educación el alcance se está viendo ampliado debido a la existencia de una comunicación más allá del aula (e-learning). La Universidad, como fuente de innovación en el método educativo, está adaptando su modelo con propuestas como la aquí descrita. A través de la implicación del alumno en proyectos de e-learning con países en vías de desarrollo, se trata de mejorar la motivación del estudiante, el desarrollo de un conjunto de competencias transversales y la transferencia tecnológica en el ámbito de la cooperación para el desarrollo. En este artículo se presenta también la experiencia propia en un caso real, con la que los participantes han logrado cumplir este triple objetivo

Global air conditioning performance indicator (ACPI) for buildings, in tropical climate

The selection of the most suitable HVAC technology for buildings, is a complex challenge. Many factors such as, the features of the building, climatic conditions, energy consumption, Indoor Air Quality (IAQ), thermal comfort, regulations, aspects, economic and environmental aspects, all of which are shown on a local and national scope. There is no standard methodology that guarantees a single criterion for the selection of HVAC systems. Therefore, in its solution, as in almost all decision-making problems in the field of engineering, two different aspects are considered, theoretical and practical (Moreno, 2002) [1], thus forming a typical multi-criteria decision problem. This study proposes an integral performance indicator for the selection of air conditioning systems (ACPI), based on the multicriteria method of the Analytic Hierarchy Process (AHP), in order to choose the best HVAC system variant, based on its classification by integrating energy, environmental, and economic criteria. For the definition of the criteria, studies on HVAC system selection were reviewed and classified, applying multi-criteria on methods. The criteria were weighted based on surveys issued by a team made up of Professors/Researchers, architects, engineers, installers and managers linked to the HVAC sector. The ACPI model obtained, shows that the highest weighting corresponds to building energy consumption index 26.6%, IAQ 20.6%, thermal comfort 18.6%, CO2 emissions 12.1%, and finally, investment costs, operation and maintenance costs 11.6% and 10.3% respectively. The proposed ACPI, together with its analysis methodology, will allow researchers, architects, engineers, and government administration, to consider a wide range of alternative HVAC systems applied in buildings. With this, it will be possible to select them based on a decision-making model with a reliable source of information

Energy evaluation and energy savings analysis with the 2 selection of AC systems in an educational building

This paper presents an energy performance assessment on an educational building in Barranquilla, Colombia. The electricity consumption performance was assessed using the software DesignBuilder for two different Air Conditioning (AC) systems. The current electricity intensity is 215.3 kWh/m2 -year and centralized AC systems with individual fan coils and a water chiller share 66% of the total consumption and lighting at 16%. The simulation of the AC technology change to Variable Refrigerant Flow (VRF) resulted in an improvement of 38% in AC energy intensity with 88 kWh/m2 -year and significant savings in electricity consumption and life-cycle cost of AC systems in buildings.Este artículo presenta una evaluación del desempeño energético en un edificio educativo en Barranquilla, Colombia. El rendimiento del consumo de electricidad se evaluó mediante el software DesignBuilder para dos sistemas de aire acondicionado (AC) diferentes. La intensidad actual de la electricidad es 215,3 kWh / m2-año y sistemas de aire acondicionado centralizados con fan coils individuales y un enfriador de agua compartido 66% del consumo total e iluminación al 16%. La simulación de la tecnología AC cambia a El flujo de refrigerante variable (VRF) resultó en una mejora del 38% en la intensidad de energía de CA con 88 kWh / m2 al año y ahorros significativos en el consumo de electricidad y el costo del ciclo de vida de los sistemas de CA en edificios

c&d-learning implementation architecture: Adapting e-learning to developing countries

From the educational point of view, the most widespread method in developing countries is on-site education. Technical and economic resources cannot support conventional distance learning infrastructures and it is even worse for courses in universities. They usually suffer a lack of qualified faculty staff, especially in technical degrees. The literature suggest that e-learning is a suitable solution for this problem, but its methods are developed attending to educational necessities of the First World and cannot be applied directly to other contexts. The proposed methodology is a variant of traditional e-learning adapted to the needs of developing countries. E-learning for Cooperation and Development (c&d-learning) is oriented to be used for educational institutions without adequate technical or human resources. In this paper we describe the c&d-learning implementation architecture based on three main phases: hardware, communication and software; e.g. computer and technical equipping, internet accessing and e-learning platform adaptation. Proper adaptation of educational contents to c&d-learning is discussed and a real case of application in which the authors are involved is described: the Ngozi University at Burundi

University Networking in Developing Countries based on C4D-Learning

In recent years, the establishment of cooperation networks between universities is one of the most important trends in higher education all over the world. Well recognized local and international university networks have been implemented in most educational institutions. It is common to find associations of various prestigious universities collaborating in a high-­‐technology research project including a very specialized teaching as well. This is the most common cooperation networks among higher education institutions in developed countries. An increasingly common type of networking between developed and developing universities is related to cooperation for development. This is the case of many universities in Africa that are needed for external help in order to improve its capabilities. Numerous memorandums of understanding regarding first world institutions that collaborate with universities in developing countries describe contributions of eventual visiting professors, teaching material and courses. But probably there exist another type of more important, but less explored association, such as networking among developing universities. The new goal, in this case, is not only the excellence but also the mutual development

Pt-zeolites as active catalysts for the removal of chlorate in water by hydrogenation reactions

[EN] Catalytic hydrogenation is used to remove chlorate ions from water streams by using platinum catalysts supported on zeolites with different topologies (FAU, BEA, MWW, MFI and MOR), Si/Al ratio and compensating cation. It is observed that there is an important influence of the zeolite characteristics on the catalytic activity. The best results have been obtained with the catalyst supported on zeolites with a high number of acid centres, this is with a low Si/Al ratio and with protons, as counter-cation species compensating aluminium charge. The acid sites favour the interaction of the catalyst with the reactants and influence the neighbouring Pt species improving the redox properties of the catalyst. It is shown that with an adequate number of acid sites it is possible to decrease the metal content, keeping the same catalytic activity, by increasing the metal dispersion. The highest activity is obtained with an acidic FAU zeolite, with low Si/Al ratio and 1 wt% of Pt added by ion exchange. This catalyst is able to simultaneously reduce chlorate and chlorite ions and chlorate and bromate ions indicating that it is a multifunctional catalyst that can be utilized for removing different pollutants in water.The authors are grateful for the financial support by the Spanish Ministry of Science and Innovation (CEX2021-001230-S grant funded by MCIN/AEI/10.13039/501100011033, and TED2021-131715B-I00 grant funded by MCIN/AEI/10.13039/501100011033 and by "ERDF A way of making Europe " by the European Union NextGenerationEU/PRTR) . Financial support by the Generalitat Valenciana (Prometeo 2021/077) is also acknowledged. A. Pla-Hernandez thanks Spanish Ministry of Science and Innovation for the pre-doctoral grant PRE2019-088100, associated with the project RTI2018-101784-B-I00.Plá-Hernandez, A.; Rey Garcia, F.; Palomares Gimeno, AE. (2024). Pt-zeolites as active catalysts for the removal of chlorate in water by hydrogenation reactions. Catalysis Today. 429. https://doi.org/10.1016/j.cattod.2023.11446142