Documents published in Scipedia

• VHF Antenna Integrated into a Classical Fibre Metal Laminate Fuselage Panel

  J. Rotgerink, C. Heuts, J. Verpoorte, C. Hengel

  Collection of Métodos de Test (2021). 2

  
  

  Abstract

  Replacement of protruding antennas by integrated alternatives will reduce the energy consumption and NOx and CO2 emissions of an aircraft. This paper proposes and integrated VHF cavity backed slot antenna that is suitable to replace blade antennas. To reduce the size of the cavity a parallel plate resonator is used. The slot is integrated into a fibre metal laminate fuselage panel. A bookleafing principle is used to reinforce the panel at the position of the slot, making sure the material quality is not reduced. Measurement results of a demonstrator antenna show the feasibility of the proposed antenna. Moreover, the paper discusses several electromagnetic and structural design trade-offs for this integrated antenna.

  Abstract
  Replacement of protruding antennas by integrated alternatives will reduce the energy consumption and NOx and CO2 emissions of an aircraft. This paper proposes and integrated [...]

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• Dinámia Poblacional del SIDA en México de 1983 a 2012: un estudio retrospectivo y prospectivo

  M. Reyna, L. Hernández, J. Ortiz, K. Su, K. Imamoto, M. Kanematsu, K. Teranishi, C. Kiyohara

  Collection of Métodos de Test (2020). 7

  
  

  Abstract

  La epidemiología del SIDA es peculiar pues solo hay tres posibles estados: susceptible, infectado y muerto; a diferencia de otras infecciones donde se puede presentar también las fases de inmune, y hay una posible transición entre los estados infectado y susceptible. Ello junto con la esperanza de vida actual de una persona infectada en tratamiento, genera una dinámica acumulativa de casos. Esta peculiaridad sugiere ya un comportamiento sigmoidal no simétrico (Modelo de Gompertz). En este trabajo se establecen similitudes y diferencias significativas del comportamiento de la epidemia de SIDA en los últimos treinta años considerando diferentes escenarios: caso Nacional, Estatal (Zacatecas), diferenciado por sexo, por edad y por forma de contagio; haciendo comparativos de los para ́metros de los ajustes tipo Gompertz, en cada contexto.

  Abstract
  La epidemiología del SIDA es peculiar pues solo hay tres posibles estados: susceptible, infectado y muerto; a diferencia de otras infecciones donde se puede presentar [...]

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• The Application of Electric Drive Technologies in City Buses

  Z. Živanović, Z. Nikolić

  Collection of Métodos de Test (2020). 9

  
  

  Abstract

  The development of innovative technologies is increasingly oriented towards electrification of vehicle propulsion systems expected to lead to: a reduction of harmful emissions, an increased efficiency of vehicles, improved performances, a reduction of fuel consumption, a reduction of noise, and potentially lower maintenance costs. An electric drive technology implies a technol‐ ogy employing at least one drive device called electric motor. Three key electric drive technol‐ ogies are: hybrid electric, battery electric, and fuel cell electric technologies. Document type: Part of book or chapter of book

  Abstract
  The development of innovative technologies is increasingly oriented towards electrification of vehicle propulsion systems expected to lead to: a reduction of harmful emissions, [...]

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• Social aspects of place experience in mobile work/life practices

  L. Ciolfi, B. Gray, A. D’Andrea

  Collection of Métodos de Test (2021). 8

  
  

  Abstract

  eer-reviewed\nThis chapter examines the importance of “where” mobile work/life practices\noccur. By discussing excerpts of data collected through in-depth interviews\nwith mobile professionals, we focus on the importance of place for mobility, and\nhighlight the social character of place and the intrinsically social motivations of\nworkers when making decisions regarding where to move. In order to show how\nthe experience of mobility is grounded within place as a socially significant construct,\nwe concentrate on three analytical themes: place as an essential component\nof social/collaborative work, place as expressive of organizational needs and characteristics,\nand place as facilitating a blending of work/life strategies and relationships.\nACCEPTED\nPeer reviewed Document type: Part of book or chapter of book

  Abstract
  eer-reviewed\nThis chapter examines the importance of “where” mobile work/life practices\noccur. By discussing excerpts of data collected through in-depth interviews\nwith [...]

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• Traffic Measurements for Link Dimensioning

  M. Brunner, R. van de Meent, A. Pras, A. Keller, M. Mandjes, H. van den Berg, L. Nieuwenhuis, M. Brunner

  Collection of Métodos de Test (2020). 8

  
  

  Abstract

  Traditional traffic measurements meter throughput on time scales in the order of 5 minutes, e.g., using the Multi Router Traffic Grapher (MRTG) tool. The time scale on which users and machines perceive Quality of Service (QoS) is, obviously, orders of magnitudes smaller. One of many possible reasons for degradation of the perceived quality, is congestion on links along the path network packets traverse. In order to prevent quality degradation due to congestion, network links have to be dimensioned in such a way that they appropriately cater for traffic bursts on time scales similarly small to the time scale that determines perceived QoS. It is well-known that variability of link load on small time scales (e.g., 10 milliseconds) is larger than on large time scales (e.g., 5 minutes). Few quantitative figures are known, however, about the magnitude of the differences between fine and coarse-grained measurements. The novel aspect of this paper is that it quantifies the differences in measured link load on small and large time scales. The paper describes two case studies. One of the surprising results is that, even for a network with 2000 users, the difference between short-term and long-term average load can be more than 100%. This leads to the conclusion that, in order to prevent congestion, it may not be sufficient to use the 5 minute MRTG maximum and add a small safety margin. Document type: Part of book or chapter of book

  Abstract
  Traditional traffic measurements meter throughput on time scales in the order of 5 minutes, e.g., using the Multi Router Traffic Grapher (MRTG) tool. The time scale on which [...]

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• Global Inspection, Diagnosis and Repair System for Buildings: Homogenising the Classification of Repair Techniques

  C. Pereira, J. Brito, J. Silvestre

  Collection of Métodos de Test (2020). 6

  
  

  Abstract

  Building inspection systems are a useful tool for surveyors, standardising the collection of information. Thisresearch is framed within the development of a global inspection system based on twelve expert inspection systems for twelve types of building elements used in the envelope of current buildings. Homogenised classification lists replace the use of several records and unify designations used in fieldwork. A homogenised global classification list of repair techniques comprises, in a single component, all the techniques used to repair defects and eliminate their causes for different types of building elements. It includes curative and preventive repairs, as well as planned maintenance works. Well-defined criteria guided the harmonisation process of a large set of repair techniquesin a user-friendly list. For instance, the association of different operations in a single repair technique took into account: similarities between procedures, applicability to one type of building element, solving identical defects and the use of similar repair materials. Considering data from the validation samples of the expert inspection systems, it is observed that techniques "R-A1 Cleaning" in painted façades and "R-A12 Application of a new (adequate) cladding/finishing coat over the existent/replacement" in wall renders are the most commonly prescribed. The provision of a homogenised classification list of repair techniques is expected to improve the quality of information collected on-site and give a comprehensive view of the most relevant repair techniques used in the envelope of current buildings.

  Abstract
  Building inspection systems are a useful tool for surveyors, standardising the collection of information. Thisresearch is framed within the development of a global inspection [...]

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• Condition-Based Maintenance Models for Stone Claddings

  C. Ferreira, A. Silva, J. Brito, L. Neves

  Collection of Métodos de Test (2020). 5

  
  

  Abstract

  Most of the maintenance actions in the construction sector are still reactive and sporadic, based on subjective criteria. Usually, maintenance actions are performed when the building already presents unacceptable degradation levels, and the reactive maintenance actions carried out only correct the anomalies observed, not dealing with the causes, thus leading to additional costs and risks for owners. This study establishes a condition-based maintenance model applied to natural stone claddings. This model has a stochastic nature, in order to deal with the complexity of the degradation phenomena. For that purpose, Petri nets are used, providing an efficient tool to model the deterioration process and the maintenance decisions considered for stone claddings. The maintenance model is a full life-cycle model that encompasses: (i) the stochastic assessment of the degradation condition of the stone claddings, and their expected service life; (ii) and the inspections, maintenance and renewal processes. In this study, three maintenance strategies are considered: (i) major intervention only; (ii) combination of minor and major interventions; and (iii) combination of cleaning operations, minor and major interventions. The impact of the different maintenance strategies in the future performance and remaining service life of stone claddings is analysed, also evaluating the economic impact of each maintenance plan.

  Abstract
  Most of the maintenance actions in the construction sector are still reactive and sporadic, based on subjective criteria. Usually, maintenance actions are performed when the [...]

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• Els governs locals a Catalunya: competències i mida òptima

  C. García

  Collection of Métodos de Test (2020). 4

  
  

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• Condition-Based Maintenance Models for Stone Claddings

  C. Ferreira, A. Silva, J. Brito, L. Neves

  Example of a collection (2020). 12

  
  

  Abstract

  Most of the maintenance actions in the construction sector are still reactive and sporadic, based on subjective criteria. Usually, maintenance actions are performed when the building already presents unacceptable degradation levels, and the reactive maintenance actions carried out only correct the anomalies observed, not dealing with the causes, thus leading to additional costs and risks for owners. This study establishes a condition-based maintenance model applied to natural stone claddings. This model has a stochastic nature, in order to deal with the complexity of the degradation phenomena. For that purpose, Petri nets are used, providing an efficient tool to model the deterioration process and the maintenance decisions considered for stone claddings. The maintenance model is a full life-cycle model that encompasses: (i) the stochastic assessment of the degradation condition of the stone claddings, and their expected service life; (ii) and the inspections, maintenance and renewal processes. In this study, three maintenance strategies are considered: (i) major intervention only; (ii) combination of minor and major interventions; and (iii) combination of cleaning operations, minor and major interventions. The impact of the different maintenance strategies in the future performance and remaining service life of stone claddings is analysed, also evaluating the economic impact of each maintenance plan.

  Abstract
  Most of the maintenance actions in the construction sector are still reactive and sporadic, based on subjective criteria. Usually, maintenance actions are performed when the [...]

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• Condition-Based Maintenance Models for Stone Claddings

  C. Ferreira(1), A. Silva(1), J. Brito(1), L. Neves

  Example of a collection (2020). 10

  
  

  Abstract

  ''Most of the maintenance actions in the construction sector are still reactive and sporadic, based on subjective criteria. Usually, maintenance actions are performed when the building already presents unacceptable degradation levels, and the reactive maintenance actions carried out only correct the anomalies observed, not dealing with the causes, thus leading to additional costs and risks for owners. This study establishes a condition-based maintenance model applied to natural stone claddings. This model has a stochastic nature, in order to deal with the complexity of the degradation phenomena. For that purpose, Petri nets are used, providing an efficient tool to model the deterioration process and the maintenance decisions considered for stone claddings. The maintenance model is a full life-cycle model that encompasses: (i) the stochastic assessment of the degradation condition of the stone claddings, and their expected service life; (ii) and the inspections, maintenance and renewal processes. In this study, three maintenance strategies are considered: (i) major intervention only; (ii) combination of minor and major interventions; and (iii) combination of cleaning operations, minor and major interventions. The impact of the different maintenance strategies in the future performance and remaining service life of stone claddings is analysed, also evaluating the economic impact of each maintenance plan.''

  Abstract
  ''Most of the maintenance actions in the construction sector are still reactive and sporadic, based on subjective criteria. Usually, maintenance actions are performed when [...]

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