Le corps humain a toujours été une source d’inspiration pour les ingénieurs et les scientifiques de tous les domaines dans le monde entier. L’un des sujets les plus intéressants de la dernière décennie a été les robots humanoïdes. Les robots humanoïdes représentent les systèmes robotiques les plus complexes. Ils offrent une plus grande mobilité dans les terrains accidentés et non structurés que les véhicules à roues normaux. À l’avenir, les robots humanoïdes devraient être employés pour une variété de tâches dangereuses dans des domaines tels que les opérations de sauvetage, l’assistance aux personnes âgées, l’éducation et le déminage humanitaire. Le travail réalisé dans cette thèse est réalisé sur le robot hydraulique humanoïde HYDROïD, un humanoïde à commande hydraulique avec 52 degrés de liberté actifs, conçu pour exécuter des tâches très dynamiques comme la marche, la course et le saut. robot puisque les actionneurs hydrauliques ont un excellent rapport poids/puissance et absorbent naturellement les pics de force d’impact lors des différentes activités. L'objectif de cette thèse est de contribuer au développement des mécanismes robotiques de la cheville et du genou avec une dynamique élevée. Un nouveau mécanisme de cheville est développé afin de pallier les inconvénients des performances réalisées avec l’ancien mécanisme de cheville d'origine. Des taux de fuite et de frottement plus faibles sont obtenus en plus d’une optimisation de pression pour les articulations de la cheville. De plus, une nouvelle solution pour optimiser le poids des actionneurs hydrauliques est appliquée sur le mécanisme du genou du robot.Une telle solution comprend l’utilisation de la technologie des matériaux composites légers pour atteindre un poids et une performance optimisés pour le joint. Afin d’appliquer des méthodologies de contrôle sur les mécanismes de la cheville et du genou, un modèle géométrique inverse pour les deux mécanismes est présenté. Le contrôle de position est utilisé pour contrôler les angles des articulations de la cheville et les mécanismes du genou. Enfin, les conclusions et les perspectives d’avenir sont présentées dans le dernier chapitre. / Human body has always been an inspiration for engineers and scientists from all fields all over the world. One of the most interesting topics in the last decade was humanoid robots. Humanoid robots represent the most complex robotic systems. They provide greater mobility in rough and unstructured terrain than the normal wheeled vehicles. In the future, humanoid robots are expected to be employed for a variety of dangerous tasks in fields like rescue operations, assisting elderly people, education and humanitarian demining. The work achieved in this dissertation is performed on the humanoid hydraulic robot HYDROïD. It is hydraulically actuated humanoid featuring 52 active degrees of freedom and is designed to perform highly dynamic tasks like walking, running and jumping. Hydraulic power was chosen for this robot since hydraulic actuators have an excellent power to weight ratio and naturally absorb impact force peaks during different activities. The objective of this dissertation is to contribute toward the development of ahighly dynamic robotic ankle and knee mechanisms. A new ankle mechanism islooked for in order to tackle the drawbacks raised by the performances achievedwith the original old ankle mechanism. Lower leakage and friction rates areachieved in addition to a pressure optimization for the ankle joints. Moreover, anew solution for optimizing the weight of hydraulic actuators is applied on theknee mechanism of the robot. Such solution includes the usage of light compositematerial technology to achieve optimized weight and performance for the joint.In order to apply control methodologies on the ankle and knee mechanisms,inverse geometrical model for the both mechanism are presented. Position controlis used to control the joints angles of the ankle and the knee mechanisms. Finally,the conclusions and the future perspectives are presented in the last chapter.

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<p dir="ltr">This thesis presents a comprehensive dynamic modeling and model calibration framework and experimental validations for air-source heat pumps under cycling of frosting and reverse-cycle defrosting operations. </p>

<p>The objectives of this investigation were to experimentally and numerically assess the performance of a ball bearing supported turbocharger (TC). Turbochargers are mechanical devices used to improve the efficiency of modern engines. Using ball bearings improves the TC efficiency, and represents one of many evolving high-speed applications for ball bearings.</p> <p>The experimental objectives of this investigation were to design and develop a turbocharger test rig (TTR) to measure the shaft whirl of the rotating assembly and the axial and frictional loads experienced by the bearing cartridge. The TTR contains a ball bearing TC which was instrumented and operated under a variety of test conditions including rotational speeds up to 55,000 rpm. In order to measure the axial loads on the compressor and turbine sides, customized sensors were designed, fabricated and integrated into the TC housing. The anti-rotation (AR) pin, which normally prevents the bearing cartridge from rotating, was replaced with a custom-made sensor to measure frictional losses in the bearing cartridge.  These sensors were designed to minimally affect the operation of the TC. Proximity probes were initially installed on the compressor side and later on the turbine side to monitor shaft whirl using targets attached to the ends of the impellers. An assembly to record axial shaft motion with a proximity probe was also developed. Axial load and motion results indicated that the compressor side bears most of the axial load. As the backpressure or the speed of the TC increased the axial load also increased. Frictional measurements from the AR pin sensor demonstrated low power losses in the ball bearing cartridge. For certain shaft speed ranges, the data from the sensors illustrated periodic trends in response to subsynchronous whirl of the shaft.</p> <p>The numerical modeling objectives of this investigation were to characterize the dynamics of the ball bearing supported TC. In this TC, the compressor, turbine and shaft are supported by a bearing cartridge composed of back-to-back angular contact ball bearings. The cartridge is supported by squeeze film dampers (SFDs) and is prevented from rotation by the AR pin. To achieve the objectives, first an equivalent bearing model was developed to investigate the bearing dynamics and whirl of the TC rotating assembly. The TC bearing cartridge was modeled with a single deep groove ball bearing (DGBB) using the discrete element method. The SFD which supports the bearing was modeled with a bilinear spring and damper. A DGBB was used because it can support axial load in both directions. This model was then extended to include a flexible shaft represented by tetrahedral finite elements and supported by an ACBB cartridge. After this model was used to reproduce the whirl from the test rig, the bearing internal geometry and SFD properties were adjusted to determine their effect on shaft whirl. Wear and damage criteria were also developed to evaluate the simulation results. The best simulation result was obtained with a small clearance in the bearing and with a stiffer SFD. The clearance was necessary as the shaft and bearing deform at high speeds, preloading the bearing.</p> <p>The best simulation result was found to have reduced sliding and limited variation in contact force, which should lead to reduced friction and improved overall life. This study demonstrates the importance of taking the bearing system into account while designing a TC or other high speed mechanical system, as the bearing and SFD properties can have a significant impact on the system performance.</p>

В рамках данной работы изучены особенности использования систем поддержки взаимодействия с клиентами в работе колл-центра. Рассмотрены возможности архитектурного подхода в разработке модели информационно-сервисной поддержки. Осуществлен анализ тенденций использования CRM-систем в колл-центрах. Осуществлена оценка результативности использования информационно-сервисной поддержки работы колл-центра. Построена полная модель архитектуры ООО «Нейтив Фарм». На основе процессного подхода детально рассмотрены все фазы проекта по информатизации колл-центра. Разработана и реализована имитационная модель управления проектом разработки и внедрения проекта информационно-сервисной поддержки работы колл-центра на основе различных сценарием. Осуществлена оценка эффективности внедрения новой CRM-системы в деятельность колл-центра. / Within the framework of this work, the features of using customer interaction support systems in the work of a call center were studied. The possibilities of the architectural approach in the development of the model of information and service support are considered. An analysis of trends in the use of CRM-systems in call centers was carried out. An assessment of the effectiveness of the use of information and service support for the work of the call center was carried out. A complete model of the architecture of Native Pharm LLC was built. Based on the process approach, all phases of the call center informatization project are considered in detail. A simulation model for project management for the development and implementation of a call center information and service support project based on various scenarios has been developed and implemented. An assessment was made of the effectiveness of introducing a new CRM system into the activities of the call center.

В диссертации были изучены особенности применения цифровых сервисов по управлению научной деятельностью образовательной организации. Рассмотрены возможности архитектурного подхода в разработке сервиса по управлению научной деятельностью. Осуществлен анализ текущего состояния научной деятельности ГОУ ВПО «Донецкого национального университета». Построена полная модель архитектуры ГОУ ВПО «Донецкий национальный университет». Разработан цифровой сервис «Scientific and information portal» с использованием веб-ориентированной среды Oracle APEX. Разработана и реализована имитационная модель управления затратами при внедрении цифрового сервиса в управление научной деятельностью образовательной организации. / In the dissertation, the features of the use of digital services for the management of scientific activities of an educational organization were studied. The possibilities of an architectural approach in the development of a service for the management of scientific activities are considered. The analysis of the current state of scientific activity of the Donetsk National University is carried out. A complete model of the architecture of the State Educational Institution of Higher Education "Donetsk National University" has been built. The digital service "Scientific and information portal" has been developed using the Oracle APEX web-oriented environment. A simulation model of cost management has been developed and implemented when implementing a digital service in the management of scientific activities of an educational organization.

Была рассмотрена инновационная деятельность технологических процессов на угледобывающих предприятиях, построена полная модель архитектуры деятельности угледобывающего предприятия ГП «Шахта Комсомолец Донбасса», отражающая полный анализ деятельности предприятия с теоретической и практической точки зрения данных. Разработана система мониторинга, с помощью использования данной системы диспетчер сможет контролировать отслеживания всех процессов, связанные с образованием метана, которые будут происходить в шахте для своевременного обнаружения большого количества газа на участках и его устранения. Разработана имитационная модель управления угледобывающего предприятия ГП «Шахта Комсомолец Донбасса», позволяющая проводить анализ эффективности предприятия, предопределять результаты других показателей деятельности компании, отражать конечные результаты, а также осуществлять прогноз и планирование на основе различных сценариев. / The innovative activity of technological processes at coal-mining enterprises was considered, a complete model of the architecture of the activity of the coal-mining enterprise SE Komsomolets Donbassa Mine was built, reflecting a complete analysis of the enterprise's activities from a theoretical and practical data point of view. A monitoring system has been developed, using this system, the dispatcher will be able to monitor the tracking of all processes associated with the formation of methane that will occur in the mine for the timely detection of large amounts of gas in the areas and its elimination. A simulation model for the management of a coal mining enterprise SE "Komsomolets Donbassa Mine" has been developed, which makes it possible to analyze the effectiveness of the enterprise, predetermine the results of other indicators of the company's performance, reflect the final results, and also carry out forecasting and planning based on various scenarios.

<p dir="ltr">The U.S. food supply chain, particularly the beef industry, faces growing demands for transparency and traceability due to increased consumer awareness of environmental and social impacts. A lack of transparency and access to information, along with misinformation, pose challenges to brand trust and supply chain efficiency. Emerging information technologies like RFID and blockchain are being explored to enhance traceability and information transparency, forming the topic of this dissertation.</p><p dir="ltr">This study aims to understand how the growing demand for transparency in the U.S. beef industry could reshape its supply chain structure and dynamics. It comprehensively examines the potential of information technologies like blockchain to enhance traceability, reduce transaction costs and information asymmetry and shift the supply chain structure to vertical coordination.</p><p dir="ltr">To achieve these objectives, we employed System Dynamics (SD) to model the U.S beef supply chain from 2013 to 2022, leveraging on existing literature and statistical data. This methodology was selected because of its unique ability to capture dynamic complexities and feedback among variables, allowing us to assess market dynamics and evaluate potential changes in the beef supply chain under different information technology scenarios. The model was evaluated through a series of tests and demonstrated its efficacy in simulating and analyzing the dynamics of the beef supply chain.</p><p dir="ltr">We simulated a wide range of key policy initiatives on both supply and demand sides of the beef supply chain. Our findings reveal that blockchain adoption is influenced by various factors such as market dynamics, consumer preferences, and existing power imbalances within the supply chain. Scenario analyses suggest that larger firms may be less incentivized to adopt blockchain if the market isn't ready for transparency, due to high implementation costs. Conversely, smaller firms could benefit from reduced transaction costs. Also, our results show an increased willingness to pay for transparent beef boosts the market for smaller firms and raises beef prices. Regulatory intervention may be necessary to balance the power dynamic within the supply chain, especially considering the market power held by packers.</p><p dir="ltr">This study fills existing knowledge gaps and provides valuable insights for beef supply chain stakeholders. It organizes complex data into clear, communicable causal loop diagrams and then introduces a comprehensive U.S. beef supply stock-and-flow diagram, grounded in literature, data, and trends. Finally, by synthesizing complex data and providing practical tools for decision-making, this research offers a foundation for future studies and policy recommendations in the field of supply chain transparency.</p>

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