Predicting expected TCP throughput using genetic algorithm

Predicting the expected throughput of TCP is important for several aspects such as e.g. determining handover criteria for future multihomed mobile nodes or determining the expected throughput of a given MPTCP subflow for load-balancing reasons. However, this is challenging due to time varying behavior of the underlying network characteristics. In this paper, we present a genetic-algorithm-based prediction model for estimating TCP throughput values. Our approach tries to find the best matching combination of mathematical functions that approximate a given time series that accounts for the TCP throughput samples using genetic algorithm. Based on collected historical datapoints about measured TCP throughput samples, our algorithm estimates expected throughput over time. We evaluate the quality of the prediction using different selection and diversity strategies for creating new chromosomes. Also, we explore the use of different fitness functions in order to evaluate the goodness of a chromosome. The goal is to show how different tuning on the genetic algorithm may have an impact on the prediction. Using extensive simulations over several TCP throughput traces, we find that the genetic algorithm successfully finds reasonable matching mathematical functions that allow to describe the TCP sampled throughput values with good fidelity. We also explore the effectiveness of predicting time series throughput samples for a given prediction horizon and estimate the prediction error and confidence.Peer ReviewedPostprint (author's final draft

Enhancing pronunciation through interactive subtitles in students of 10th and 11th grade of high school CDA

videos collected from studentsTo develop pronunciation skills is imperative to communicate with the others, nevertheless, regrettably it is one of the skills less work at class. Fraser (2000) affirmed that the pronunciation is one of the skills most difficult of managing in learning of a second language, but it is very important to speak fluently and with foreign accent. Based on this idea, this project aimed to provide a learning tool (ingles.in) to students of 10th and 11th grade of the CDA school, in order that students could improve their listening and pronunciation of the English language through the comprehensive language and under the Natural Method proposed by Krashen & Terrell in 1983, in which students are able to acquire a language through imitation and feedback on their learning process. The project was carried out through a mixed methods design between experimental research and descriptive research for quantitative data in which, through descriptive and inferential statistics, it is intended to address the research problem and the hypothesis to verify and conclude the effectiveness of the ingles.in tool in the students' learning process. The findings of this project contribute to verify if the ingles.in learning tool helped students to improve their pronunciation, additionally it will provide material, such as student-generated audios, that will help to support other projects in the field of pronunciation.Develop pronunciation skills is imperative to communicate with others, but unfortunately is one of the skills less work in class. However, pronunciation is one of the most difficult skills to achieve in the learning of a second language but is so important to speak with fluently and with foreign accent. Hence, this project aimed to analyze the improvement of pronunciation of the second language English through ICT in students of 10th and 11th grade of High school of Colegio Diocesano de la Asunción de Zipaquirá (CDA) school using the digital platform ingles.in, which allows students to improve listening and pronunciation through comprehensive language input as in the Natural Method and receive feedback about their learning process. The project bellow is conducted through a mix-method design between true experimental research and descriptive research for quantitative data in which through descriptive and inferential statistic it is pretended to address the research problem and the hypothesis to verify and conclude the effectiveness of ingles.in in the learning process. The findings of the present project contribute to verify if the learning tool ingles.in help students to improve their pronunciation and collect material, such audios, that support other projects in the pronunciation field

Assessing the Performance of Reconditioned Railroad Tapered-Roller Bearings Used in Freight Rail Service

The rail industry currently utilizes two wayside detection systems to monitor the health of freight railcar bearings in service: The Trackside Acoustic Detection System (TADS™) and the wayside Hot-Box Detector (HBD). Bearings that are removed from service are sent to specialized facilities where they undergo a reconditioning process before the bearings can be returned to rail service. The reconditioning process has been used for decades although there has been no previous study on the effectiveness of the reconditioning process on defective bearings that were removed from service. This persuaded the researchers from the University Transportation Center for Railway Safety (UTRCS) and the Transportation Technology Center Inc. (TTCI) to design an experimental study to assess the efficacy of the reconditioning process. The work in this thesis summarizes the results of the temperature and vibration signatures of twenty bearings. To assess the effectiveness of the reconditioning process, twelve of the twenty bearings were tested pre- and post-reconditioning process. The remaining eight bearings were tested post-reconditioning for a complete service life testing consisting of approximately 400,000 km (~250,000 mi) at the UTCRS testing facility

Factor climático y sector agropecuario en Argentina : un abordaje antropológico

El presente trabajo analiza la relación entre el factor climático, las prácticas productivas agrícolas y las estrategias de mitigación. A partir de dos estudios de caso, se analizan las vulnerabilidades de las distintas categorías de productores agropecuarios frente al factor climático en relación el capital social, cognitivo y político que los actores logran movilizar en sus proyectos productivos. Las necesidades de conocimiento experto sobre el clima están asociadas al perfil socioproductivo y al contexto local. Las formas en que dicho conocimiento es integrado por el productor también están mediadas por factores cognitivos, materiales y simbólicos. Se abordan las consecuencias respecto de la producción del conocimiento experto sobre clima y de las políticas públicas destinadas al sector agropecuario

Notes sur une rencontre

Une longue conversation Les années quatre‑vingt‑dix resteront dans l’histoire argentine comme la décade des mirages premièr‑mondistes. Le chef de tribu, Carlos Menem (président de 1989 à 1995 et réélu de 1995 à 2000), assisté par son shaman de la « génération Chicago boy », l’économiste Domingo Cavallo, a eu peu de mal à convaincre les Argentins qu’avec quelques efforts conjoncturels, ils gagneraient les rangs du monde industrialisé de manière pleine et définitive. En effet, en supportant les..

Chercheur-décideur

Dans cet article j’interroge les modes d’interaction entre les décideurs des politiques publiques dans le secteur de la santé et les chercheurs sollicités par les instances étatiques afin de réaliser des enquêtes destinées à fournir des informations pour les prises de décision. Je montre l’émergence d’un espace de communication entre ces acteurs, leurs horizons s’y articulent de manière à produire un bénéfice spécifique à chaque partenaire. L’intervention des chercheurs dans les champs sociaux produit une dyna­mique qui s’inscrit dans les pratiques sociales à travers lesquelles sont mises en place les politiques publiques.In this article I examine modes of interaction between public policy decision-makers in the field of health and researchers called upon by state bodies to carry out studies designed to provide information for decision-making. I show the emergence of a communication space between these actors, in which their perspectives articulate with each other in such a way as to produce a specific benefit to each partner. The intervention of researchers in different social spheres produces a dynamic which is part of the social practices through which public policies are implemented

Vers un modèle de développement et d'identités professionnelles agricoles globalisés: Dynamiques d’innovation autour du semis direct en Argentine et en France

Cet article éclaire par une analyse croisée des dynamiques de développement du semis direct (SD) en Argentine et en France, la globalisation des systèmes d’innovation et des identités professionnelles agricoles autour des productions de grandes cultures. Il montre les proximités entre les dispositifs liés au développement de cette technologie dans les deux pays, en soulignant l’engagement des multinationales agrochimiques et semencières auprès des agriculteurs et d’organisations de lobbying. Les identités professionnelles des agriculteurs concernés présentent également de profondes similitudes, témoignant d’un sentiment d’appartenance à une définition commune du métier d’agriculteur basée notamment sur la connaissance du fonctionnement des sols et l’objectif partagé de leur conservation .Fil: Hernandez, Valeria Alicia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Des chimères high-tech

Observer la biologie dans la société. Etudier les bouleversements symboliques consécutifs de l’affranchissement de la frontière « naturelle des choses » qui s’est opéré grâce à la technoscience de la fin du siècle dernier. Repenser des notions fondamentales de l’humanité élaborées par la modernité, comme la liberté ou la créativité, à partir de l’ultime révolution biologique : celle de la génétique moderne. Telles sont quelques‑unes des ques­tions que l’anthropologie peut développer avec inté..