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My thesis aims at contributing to the development and improvement of the upper body of HYDROïD robot for bi-manual tasks, while basing on a bio-mechanical study of this part of the human being. To reach our major goal, this work adopts, at first, a novel hybrid structure of 4 degrees of freedom (DOF) for the trunk of the robot, distributed in three DOF at the lumbar level and one DOF at the thoracic level. This structure was identified after an analysis of the work-space of a multi-body model feigning the vertebral column of a human being, and an optimization study of that model allowing the synthesis of the envisaged structure. Secondly, an improvement of the kinematics of the robor arm was organized, by introducing the notion of the shoulder complex in the present structure. The choice of this new degree of freedom was the fruit of a systematic approach to increase the anthropomorphism geometry of the arm wished towards a humanitarian arm of the same size.The two proposed structures crossed afterward by the mechanical design phase while respecting all the geometrical constraints and by using the hydraulic energy as being the type of actuation of these systems. Finally, the Inverse Geometrical Model (IGM) for the generic solution of the trunk was established and its adaptation to our particular case was identified. An optimized solution for this mechanism based on 2 various criteria was then given., Ma thèse vise à contribuer au développement et l’amélioration de la cinématique de la partie supérieure du robot HYDROïD pour des tâches bi-manuelles, tout en basant sur une étude biomécanique de cette partie chez l’être humain.Pour atteindre notre objectif majeur, ce travail adopte dans un premier temps une nouvelle structure hybride de 4 degrés de liberté (ddl) pour le torse du robot, distribués en 3 ddl au niveau lombaire et un ddl au niveau thoracique. Cette structure était identifiée après une analyse de l’espace de travail d’un modèle multi-corps simulant la colonne vertébrale d’un être humain, et une étude d’optimisation de ce modèle permettant la synthèse de la structure envisagée.Dans un second temps, une amélioration de la cinématique du bras du robot a été mise en place, en introduisant la notion de l’épaule complexe au présente structure. Le choix de ce nouveau degré de liberté était le fruit d’une approche systématique pour augmenter l’anthropomorphisme géométrie du bras souhaité vers un bras humain de la même taille.Les 2 structures proposées ont passé par la suite par la phase de conception mécanique tout en respectant les contraintes géométriques et en se basant sur l’énergie hydraulique comme étant l’énergie d’ actionnement de ces systèmes. Enfin, le Modèle Géometrique Inverse (MGI) pour la solution générique du torse a été établi et son adaptation à notre cas particulier a été identifiée. Une solution optimisée pour ce mécanisme basée sur 2 différents critères a ensuite été donnée.

Imputation of missing data is a critical part of accurate data analysis and modeling. This paper presents 3D imputation as a new data-driven methodology to estimate missing values in time series data. The method is based on the assumption that all the observed data in a time series are related with each other and with data of the some other series. The available data is placed in a three-dimensional space so that the increasing or decreasing relationships between the observed data are appropriately represented. For the estimation of each missing value, the method searches and determines the best possible group of estimator data within the data space. Different data groups are found and used for the estimations of each individual group of missing data. The method is validated by removing and estimating all the observed monthly flow data of Saraykoy station on Buyuk Menderes River in Turkey. Data of the downstream Burhaniye station constituted the second data layer in the model. High correlation values were obtained for all years between observations and estimations and the missing data of Saraykoy station was also estimated by using the proposed method. (C) 2016 Sharif University of Technology. All rights reserved.

The heterogeneity of traffic and the lack of lane discipline on the roads in India and other developing countries add complexity to the analysis and modeling of traffic. It is generally believed that it is important to take heterogeneity into account in traffic modeling. The aim of the present study is to check the validity of this assumption by analyzing the effect of incorporating heterogeneity in a macroscopic level traffic flow analysis. The application considered is real-time congestion analysis on Indian roads. Traffic density is considered as the congestion indicator. The measurement of density is difficult since it is a spatial parameter. It is usually estimated from other traffic parameters that can be readily measured using available sensors. A model-based estimation scheme using Kalman filtering has been employed to estimate traffic density. A non-continuum macroscopic model was attempted based on the lumped parameter approach. All the traffic variables were quantified without considering traffic lanes in order to take into account the lack of lane discipline. The effect of heterogeneity has been studied by incorporating static values of Passenger Car Units (PCU), dynamic values of Two Wheeler Units (TWU) and considering different classes of vehicles explicitly in the modeling process. The proposed estimation schemes without and with heterogeneity have been compared. The results have been corroborated using data collected from a road stretch in Chennai, India. The study shows that the significance of incorporating heterogeneity into the modeling of mixed traffic at the macroscopic level was not very significant. � 2014 Vilnius Gediminas Technical University (VGTU) Press.

Seismic damage and vulnerability of five historical masonry structures surveyed after the 1999 Kocaeli and Duzce, Turkey earthquakes are discussed in this paper. The structures are located in two neighboring cities that have been struck by five very large (M-s >= 7.0) earthquakes during the 20th century alone. Older masonry mosques with arches and domes and their masonry minarets (slender towers) were among the most affected structures in this highly seismic region. While some of the religious and historical structures had virtually no damage, most structures suffered significant damage or collapsed. In the city of Bolu, for example, approximately 600-year-old Imaret, 500-year-old Kadi, 250-year-old Sarachane, and 100-year-old Yildirim Bayezid mosques suffered substantial structural damage after the 1999 earthquakes. Another historical mosque surveyed in Duzce partially collapsed. Most common factors contributing to deterioration of historical structures are also presented. Furthermore, a brief overview of issues associated with analysis and modeling of historical masonry structures is provided.

Heat waves can have devastating impacts on society, but a current weakness with the analysis and modeling of heat waves is the negligible use of the Statistical Theory of Extreme Values. This is a branch of statistics more appropriate for studying extreme events such as heat waves, floods, etc. For this study, EVT was used to develop methods for analyzing heat waves and their characteristics (frequency, intensity, duration, etc.). This analysis was performed using temperature data from Phoenix, AZ and Fort Collins, CO. This study signaled how Statistical Theory of Extreme Values can be applied to model certain features of heat waves. Results from the analysis showed an increase in the summer highest temperature and in the number of heat waves per year for both cities. This study also explored other characteristics of heat waves (heat wave duration and individual maximum temperatures within heat waves), indicating how the extreme value approach would need to be extended to fully model all features of heat waves. The results show there hasn’t been a significant change in the intensity or duration of heat waves for either city. The results as well descriptively imply a temperature dependence of daily temperatures within a heat wave for both cities. More reliable quantification of return levels for severe heat waves, including any trends in their characteristics, and other extreme events involving spells will be achieved with the continual development and future use of these methods.

Purpose: Simulation of hardness distribution in quenched steel specimen has been investigated using 3D numerical formulation. Structural mesh has been used in numerical simulation. Numerical calculations of hardness distribution in specimen made of high hardenability steel have been performed in order to define appropriate steel for manufacturing of machine part. Possibility of application of numerical model based on experimental results in steel quenching has been investigated. Methodology: Numerical simulation of the steel quenching is consisted of computation of cooling curve during the quenching and prediction of hardness at specimen points after the quenching. Hardness at specimen points is estimated by the conversion of cooling time results to hardness. Conversion is provided by the relation between cooling time and distance from the quenched end of Jominy-specimen. In this way the numerical simulation has been combined with experimental Jominy-test. Findings: Structure transformation and hardness distribution can be successfully estimated based on time, relevant to structure transformation. Relevant time for quenching results for most structural steels is cooling time from 800 to 500 °C (t8/5). Research limitations: Since high hardenability of investigated steel there are limits in application of original Jominy-specimen in simulation of quenching of steels. The modified Jominy-test enables cooling time, t8/5 higher than Jominy-test. Practical implications: The simulation of quenching based on modified Jominy-test can be applied for steels with higher hardenability. This method of simulation is especially suitable for tools and dies steels. 3D numerical simulation of quenching is more confident in practical implementation and provides more information than 2D formulation. Originality: Using the results of simple experimental test, i.e., modified Jominy-test in numerical modeling of steel quenching it is possible to achieve better results of hardness simulation.