This work presents a methodological proposal to obtain a hybrid model in order to measure the qua... more This work presents a methodological proposal to obtain a hybrid model in order to measure the quality of experience within the residential IPTV service. The paper includes a description of background information about objective and hybrid methods, the problem that needs to be resolved and the methodology to be used during the project. Our contribution towards solving the problem is to propose a hybrid model that uses quality of service parameters and a NR (No Reference) algorithm to evaluate the quality of video. This approach is not based on the results of subjective tests executed by users previously.
El artículo presenta un análisis documentado de trabajos propuestos por diferentes autores sobre ... more El artículo presenta un análisis documentado de trabajos propuestos por diferentes autores sobre como medir calidad de la experiencia para el servicio de televisión sobre protocolo IP (IPTV). Se analizan principalmente los métodos indirectos, identificando las ventajas y desventajas de cada propuesta. Se presenta un cuadro comparativo entre los diferentes métodos indirectos analizados, permitiendo dar claridad del proceso que se siguió para obtener cada modelo. Algunos modelos indirectos resultan más precisos que otros debido a la cantidad de parámetros de calidad de servicio que utilizan para su generación o porque se basan en pruebas subjetivas obtenidas con anterioridad.
This article presents advances in research to obtain a hybrid model which allows the quality of e... more This article presents advances in research to obtain a hybrid model which allows the quality of experience within the residential IPTV service to be measured. The contents include a description of background information about objective and hybrid methods, the problem that needs to be resolved and the methodology to be used during the project. Our hybrid model will use quality of service parameters and a NR (No Reference) algorithm to evaluate the quality of video. This approach is not based on the results of subjective tests put forward to users previously. I. INTRODUCTION The current growth in IPTV service leads us to forecast that by 2016 this service will represent 88% of all global Internet traffic [1]. As a result, at some point in the future, this situation could lead to congested networks, degradation in the level of service provided, and therefore, end user dissatisfaction. Based on the situation above, it is very important for service providers to be able to know the qualit...
EDUCATIONAL SELF-CORRECTING APPLICATION TOWARDS CONTINUOUS ASSESSMENT FOR E- LEARNING OF ANALYSIS OF BUILDING STRUCTURES
Revista de Educacion
The adaptation to the European Higher Educational area is an opportunity to incorporate on-line m... more The adaptation to the European Higher Educational area is an opportunity to incorporate on-line methods of education assessment in the field of the "Structural Analysis". This paper promotes the intensive use of MOODLE platform of the Technical University of Madrid, to implement the Information and Communication Technology program in this area. This article summarizes the educational experience achieved during the last courses though the use of a new software tool for continuous self-testing by the students. Individualized test are achieved by randomized variable data for each student. Several benefits for the educational purposes have arisen. Firstly, a considerable speeding of the evaluation process, and more than this, a massive input by the students. Certainly, the use of this tool can be very useful for the learning process and therefore for the improvement of the student's skills and abilities.
Learning analytics for intensive use of moodle: a case study of b-learning
The present case study focuses on how to fulfil the objectivity and reliability goals, as well as... more The present case study focuses on how to fulfil the objectivity and reliability goals, as well as the efficiency of the e-learning evaluation tools, and their integration in blended evaluation system. In order to contribute to these goals, a new branch of statistics has been chosen. The proposed techniques in this article can be easily implemented with little knowledge about arithmetic and with the help of a standard spreadsheet. These techniques allow to get the whole picture of the evaluation procedure output, in order to systematically sort the main categories of the different students, and to easily identify the outliers for further assessment. Thus, although the human factor is always necessary to ensure the trustworthiness of the evaluation procedure, it can be reasonably minimized. The statistical results obtained in this work are able to validate or invalidate the suitability of blended evaluation procedures that combine continuous on-line assessment and one or several exami...
Criteria for steel structures reinforcement: Restoration of the “Círculo de Bellas Artes” building and the Cultural Center “Casa Encendida”
Informes de la Construcción
This paper introduces the fundamental criteria for the diagnosis and restoration of steel structu... more This paper introduces the fundamental criteria for the diagnosis and restoration of steel structures. The adaptation of buildings for new uses not considered in their origins and the increasing interest in the correct conservation of the Architectural Heritage, have promoted the update of the traditional techniques typically applied in restoration of historical constructions. Among a large number of possibilities, the present work is focused on the advantages of restoration by means of turning steel structures into concrete-steel composite structures. This technique provides a large array of advantages: mechanical behavior of concrete-steel composite beams, low cost of repair and improvement of several factors, such as soundproofing and thermal insulation. Furthermore, this paper includes the repair procedure for two emblematic buildings of the Architectural Heritage in Madrid: the “Circulo de Bellas Artes” and “La Casa Encendida”.
A NEW AUTOMATIC ON-LINE EVALUATION FOR GRAPHICS APPLIED TO BUILDING STRUCTURES
ABSTRACT This article presents a new automatic evaluation for on-line graphics, its application a... more ABSTRACT This article presents a new automatic evaluation for on-line graphics, its application and the numerous advantages achieved applying this developed correcting method. The software application developed by the Innovation in Education Group “E4”, from the Technical University of Madrid, is oriented for the online self-correction of the graphic drawings that students carry out as continuous training. The adaptation to the European Higher Educational Area is an important opportunity to research about the possibilities of on-line education assessment. In this way, a new software tool has been developed for continuous self-testing by undergraduates. Using this software it is possible to evaluate the graphical answer of the students. Thus, the drawings made on-line by students are automatically corrected according to the geometry (straight lines, sloping lines or second order curves) and by sizes (depending on the specific values which define the graphics).
Non-destructive assessment of welded headed studs by acoustic test
Informes De La Construccion, 2012
ABSTRACT Headed studs are nowadays the standard steel-concrete connectors because of their compet... more ABSTRACT Headed studs are nowadays the standard steel-concrete connectors because of their competitive advantages. Firstly, they provide a high degree of safety thanks to semiautomatic electric arc welding. These welds are not suitable for typical non-destructive tests. The analytical study comprises several models. The first vibration modes have been obtained. The experimental research has developed first the measurement of the natural frequencies of 28 headed-studs in the sonic range. Then they have been tested by non-destructive and destructive tests. Finally theirs tests have been compared with their respective frequency measurements. A clear relationship between the measured frequencies and the lack of penetration of the welds has been established, that confirms the analytical prediction of this effect of the internal weld imperfections. Therefore, the feasibility of simple and absolutely non-destructive tests of welded studs by in site measurement of natural frequencies in the sonic range has been clearly established in this work.
Revista Internacional De Metodos Numericos Para Calculo Y Diseno En Ingenieria, 2013
ABSTRACT The verification of the slender compressed members of a structure is a well formulated a... more ABSTRACT The verification of the slender compressed members of a structure is a well formulated and codified problem. However, the non-linearity of the design process, combined with the no linearity of the physical problem requires an iterative process to define the piece that solves a given problem. This paper demonstrates an identity relationship between seemingly different problems, based on which we develop a theoretical approach and a simple procedure to determine, without iteration and with little margin for error, the piece needed for a given problem. The paper provides a statistical model to check that the provided procedure is safe and effective in the 98% of the problems in buildings —columns and bars from trusses—. The presented approach therefore greatly facilitates decisions in this area.
El artículo presenta un análisis documentado de trabajos propuestos por diferentes autores sobre ... more El artículo presenta un análisis documentado de trabajos propuestos por diferentes autores sobre como medir calidad de la experiencia para el servicio de televisión sobre protocolo IP (IPTV). Se analizan principalmente los métodos indirectos, identificando las ventajas y desventajas de cada propuesta. Se presenta un cuadro comparativo entre los diferentes métodos indirectos analizados, permitiendo dar claridad del proceso que se siguió para obtener cada modelo. Algunos modelos indirectos resultan más precisos que otros debido a la cantidad de parámetros de calidad de servicio que utilizan para su generación o porque se basan en pruebas subjetivas obtenidas con anterioridad.
Conexión de forjados de hormigón a soportes metálicos
... 1. Introducción ... Para aprovechar toda la potencia de las estructuras mixtas es imprescindi... more ... 1. Introducción ... Para aprovechar toda la potencia de las estructuras mixtas es imprescindible entender los principios fundamentales del funcionamiento de los dos materiales para entender el comportamiento global de la estructura y combinarlo con el conocimento del ...
This paper proposes a handover scheme supporting Multi-Protocol Label Switching (MPLS) in a Proxy... more This paper proposes a handover scheme supporting Multi-Protocol Label Switching (MPLS) in a Proxy Mobile IPv6 (PMIPv6) domain that improves the mobility and gives Quality of Service (QoS) and Traffic Engineering (TE) capabilities in wireless access networks. The proposed scheme takes advantages of both PMIPv6 and MPLS. PMIPv6 was designed to provide NETwork-based Localized Mobility Management (NETLMM) support to a Mobile Node (MN); therefore, the MN does not perform any mobility related signaling, while MPLS is used as an alternative tunneling technology between the Mobile Access Gateway (MAG) and the Local Mobility Anchor (LMA) replacing the IP-in-IP tunnels with Label Switched Path (LSP) tunnels. It can also be integrated with other QoS architectures such as Differentiated Services (DiffServ) and/or Integrated Services (IntServ). In this study, we used MATLAB to perform an analysis to evaluate the impact of introducing MPLS technology in PMIPv6 domain based on handover latency, operational overhead and packet loss during the handover. This was compared with PMIPv6, and a PMIPv6/MPLS integration. We proved that the proposed scheme can give better performance than other schemes.
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Papers by Jesus Ortiz