81,871 research outputs found

    A review of daylighting design and implementation in buildings

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    The ATLAS SCT grounding and shielding concept and implementation

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    This paper presents a complete description of Virgo, the French-Italian gravitational wave detector. The detector, built at Cascina, near Pisa (Italy), is a very large Michelson interferometer, with 3 km-long arms. In this paper, following a presentation of the physics requirements, leading to the specifications for the construction of the detector, a detailed description of all its different elements is given. These include civil engineering infrastructures, a huge ultra-high vacuum (UHV) chamber (about 6000 cubic metres), all of the optical components, including high quality mirrors and their seismic isolating suspensions, all of the electronics required to control the interferometer and for signal detection. The expected performances of these different elements are given, leading to an overall sensitivity curve as a function of the incoming gravitational wave frequency. This description represents the detector as built and used in the first data-taking runs. Improvements in different parts have been and continue to be performed, leading to better sensitivities. These will be detailed in a forthcoming paper

    High performance computing of explicit schemes for electrofusion jointing process based on message-passing paradigm

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    The research focused on heterogeneous cluster workstations comprising of a number of CPUs in single and shared architecture platform. The problem statements under consideration involved one dimensional parabolic equations. The thermal process of electrofusion jointing was also discussed. Numerical schemes of explicit type such as AGE, Brian, and Charlies Methods were employed. The parallelization of these methods were based on the domain decomposition technique. Some parallel performance measurement for these methods were also addressed. Temperature profile of the one dimensional radial model of the electrofusion process were also given

    A differential game approach to urban drainage systems control

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    © 20xx IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.Urban drainage systems (UDSs) are complex large-scale systems that carry stormwater and wastewater throughout urban areas. During heavy rain scenarios, UDSs are not able to handle the amount of extra water that enters the network and flooding occurs. Usually, this might happen because the network is not being used efficiently, i.e., some structures remain underused while many others are overused. This paper proposes a control methology based on differential game theory that aims to efficiently use the existing network elements in order to minimize overflows and properly manage the water resource. The proposed controller is tested on a typical UDS and is compared with a centralized MPC achieving similar results in terms of flooding minimization and network usage, but only using local information on distributed controllers.Peer ReviewedPostprint (author's final draft

    Quantitative analysis of numerical estimates for the permeability of porous media from lattice-Boltzmann simulations

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    During the last decade, lattice-Boltzmann (LB) simulations have been improved to become an efficient tool for determining the permeability of porous media samples. However, well known improvements of the original algorithm are often not implemented. These include for example multirelaxation time schemes or improved boundary conditions, as well as different possibilities to impose a pressure gradient. This paper shows that a significant difference of the calculated permeabilities can be found unless one uses a carefully selected setup. We present a detailed discussion of possible simulation setups and quantitative studies of the influence of simulation parameters. We illustrate our results by applying the algorithm to a Fontainebleau sandstone and by comparing our benchmark studies to other numerical permeability measurements in the literature.Comment: 14 pages, 11 figure

    Sustainability and Replicability of Multiple-Use Water Systems (MUS)

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    The concept of multiple-use water services and systems (MUS) has received increasingattention in international water and development fora and has emerged as a promising wayto enhance the social and gender equity and productivity of water systems designed forsingle use, e.g. for irrigation or water supply. In Nepal, several MUS models have beenpiloted and implemented for more than a decade by the International DevelopmentEnterprises (iDE) and a few other development organizations. Whereas the short-termbenefits of these systems on gender relationships, women's empowerment, nutrition andhealth have been documented, the sustainability and resilience of these systems has not yetbeen analyzed. The latter is the focus of the research study presented in this report, whichwas conducted by the International Water Management Institute (IWMI) in Western Nepalas part of the USAID-funded Market Access and Water Technology for Women (MAWTW)project

    Dynamic simulation model of trans-critical carbon dioxide heat pump application for boosting low temperature distribution networks in dwellings

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    This research investigates the role of new hybrid energy system applications for developing a new plant refurbishment strategy to deploy small scale smart energy systems. This work deals with a dynamic simulation of trans-critical carbon dioxide heat pump application for boosting low temperature distribution networks to share heat for dwellings. Heat pumps provide high temperature heat to use the traditional emission systems. The new plant layout consists of an air source heat pump, four trans-critical carbon dioxide heat pumps (CO2-HPs), photovoltaic arrays, and a combined heat and power (CHP) for both domestic hot water production and electricity to partially drive the heat pumps. Furthermore, electric storage devices adoption has been evaluated. That layout has been compared to the traditional one based on separated generation systems using several energy performance indicators. Additionally, a sensitivity analysis on the primary energy saving, primary fossil energy consumptions, renewable energy fraction and renewable heat, with changes in building power to heat ratios, has been carried out. Obtained results highlighted that using the hybrid system with storage device it is possible to get a saving of 50% approximately. Consequently, CO2-HPs and hybrid systems adoption could be a viable option to achieve Near Zero Energy Building (NZEB) qualification

    Security analysis of JXME-Proxyless version

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    JXME es la especificación de JXTA para dispositivos móviles con J2ME. Hay dos versiones diferentes de la aplicación JXME disponibles, cada una específica para un determinado conjunto de dispositivos, de acuerdo con sus capacidades. El principal valor de JXME es su simplicidad para crear peer-to-peer (P2P) en dispositivos limitados. Además de evaluar las funciones JXME, también es importante tener en cuenta el nivel de seguridad por defecto que se proporciona. Este artículo presenta un breve análisis de la situación actual de la seguridad en JXME, centrándose en la versión JXME-Proxyless, identifica las vulnerabilidades existentes y propone mejoras en este campo.JXME és l'especificació de JXTA per a dispositius mòbils amb J2ME. Hi ha dues versions diferents de l'aplicació JXME disponibles, cada una d'específica per a un determinat conjunt de dispositius, d'acord amb les seves capacitats. El principal valor de JXME és la seva simplicitat per crear peer-to-peer (P2P) en dispositius limitats. A més d'avaluar les funcions JXME, també és important tenir en compte el nivell de seguretat per defecte que es proporciona. Aquest article presenta un breu anàlisis de la situació actual de la seguretat en JXME, centrant-se en la versió JXME-Proxyless, identifica les vulnerabilitats existents i proposa millores en aquest camp.JXME is the JXTA specification for mobile devices using J2ME. Two different flavors of JXME implementation are available, each one specific for a particular set of devices, according to their capabilities. The main value of JXME is its simplicity to create peer-to-peer (P2P) applications in limited devices. In addition to assessing JXME functionalities, it is also important to realize the default security level provided. This paper presents a brief analysis of the current state of security in JXME, focusing on the JXME-Proxyless version, identifies existing vulnerabilities and proposes further improvements in this field
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