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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Realtidssammanställning av stora mängder data från tidsseriedatabaser / Realtime compilation of large datasets from time series databases

Rådeström, Johan, Skoog, Gustav January 2017 (has links)
Stora mängder tidsseriedata genereras och hanteras i tekniska försörjningssystem och processindustrier i syfte att möjliggöra övervakning av systemen. När tidserierna ska hämtas och sammanställas för dataanalys utgör tidsåtgången ett problem. Examensarbetet hade som syfte att ta reda på hur utvinning av tidsseriedata borde utföras för att ge bästa möjliga svarstid för systemen. För att göra hämtningen och sammanställningen så effektiv som möjligt testades och utvärderades olika tekniker och metoder. De områden som tekniker och metoder jämfördes inom var sammanställning av data inom och utanför databasen, cachning, användandet av minnesdatabaser jämfört med andra databaser, dataformat, dataöverföring, och förberäkning av data. Resultatet var att den bästa lösningen bestod av att sammanställa data parallellt utanför databasen, att använda en egen inbyggd minnesdatabas, att använda Google Protobuf som dataformat, samt att förberäkna data. / Large amounts of time series data are generated and managed within management systems and industries with the purpose to enable monitoring of the systems. When the time series is to be acquired and compiled for data analysis, the expenditure of time is a problem. This thesis was purposed to determine how the extraction of time series data should be performed to give the systems the best response time possible. To make the extraction and compilation as effective as possible, different techniques and methods were tested and evaluated. The areas that techniques and methods were compared for were compilation of data inside and outside the database, caching, usage of in-memory databases compared to other databases, dataformats, data transfer, and precalculation of data. The results showed that the best solution was to compile data in parallel outside the database, to use a custom built-in in-memory database, to use Google Protobuf as data format, and finally to use precalculated data.
42

Fast mapping of finite element field variables between meshes with different densities and element types

Scrimieri, Daniele, Afazov, S.M., Becker, A.A., Ratchev, S.M. 04 March 2020 (has links)
yes / In the simulation of a chain of manufacturing processes, several finite element packages can be employed and for each process or package a different mesh density or element type may be the most suitable. Therefore, there is a need for transferring finite element analysis (FEA) data among packages and mapping it between meshes. This paper presents efficient algorithms for mapping FEA data between meshes with different densities and element types. An in-core spatial index is created on the mesh from which FEA data is transferred. The index is represented by a dynamic grid partitioning the underlying space from which nodes and elements are drawn into equal-sized cells. Buckets containing references to the nodes indexed are associated with the cells in a many-to-one correspondence. Such an index makes nearest neighbour searches of nodes and elements much faster than sequential scans. An experimental evaluation of the mapping techniques using the index is conducted. The algorithms have been implemented in the open source finite element data exchange system FEDES.
43

Разработка методов интеграции ArchiCAD – ЛИРА-САПР (на примере промышленного здания из сборного железобетона, разрабатываемого Научно-проектной компанией «АСПект») : магистерская диссертация / Development of ArchiCAD - LIRA-CAD integration methods (by the case of a prefabricated reinforced concrete industrial building developed by ASPekt Scientific and Design Company)

Максимова, А. А., Maksimova, A. A. January 2022 (has links)
При выборе программного обеспечения, применяемого в технологиях информационного моделирования в области строительства, следует учитывать немало факторов: как возможности программного комплекса в среде разработки, так и способность выполнять специализированные расчеты и анализ по данным проекта. В диссертации рассмотрены нюансы построения корректной архитектурной модели в ArchiCAD, исследованы методы ее экспорта в ЛИРА-САПР для расчета несущих конструкций из сборного железобетона, разработаны методические рекомендации по созданию архитектурной модели, которые позволяют избежать ошибок и трудностей при передачи на расчет, а также помогают оптимизировать работу Научно-проектной компании «АСПект». / At the stage of selecting information modeling software in the field of construction, many factors should be taken into account such as the capabilities of the software complex in the development environment, and the ability to perform specialized calculations and analysis according to project data. The dissertation considers the nuances of correct architectural model building in ArchiCAD, researches the methods of its export to LIRA-CAD for calculating load-bearing structures from precast reinforced concrete, developed methodological recommendations for creating an architectural model that avoid errors and difficulties in transferring to calculation, and also help optimize the work of the Scientific and Design Company "ASPekt."
44

Разработка прототипа системы прогнозирования потребления электроэнергии промышленным предприятием по производству меди : магистерская диссертация / Development of a prototype system for forecasting electricity consumption by an industrial copper production enterprise

Лысакова, Т. Е., Lysakova, T. E. January 2023 (has links)
В работе поднимается проблема прогнозирования энергопотребления крупного промышленного предприятия. В условиях продолжающегося роста глобального энергопотребления важность экономии ресурсов стала как никогда актуальной. В работе описана модель информационной системы, которая включает: получение данных с SQL-сервера в автоматизированном режиме, передачу данных в пакет MATLAB и алгоритмическую часть для расчета анализа прогноза электропотребления. Для анализа данных используется нейронная сеть и программа, которая разработана на языке C#, способна извлекать данные с SQL-сервера предприятия из определенных таблиц и столбцов. Результат работы нейронной сети был сравнен с реальными данными по потреблению электроэнергии. Данные прогноза удовлетворяют поставленным требованиям к погрешности. / The paper raises the problem of forecasting the energy consumption of a large industrial enterprise. With the continued growth of global energy consumption, high resource savings has become more relevant than ever. The paper describes a model of the detection system, which includes: receiving data from the SQL server in automatic mode, transferring data to the MATLAB package and the algorithmic part for calculating the analysis of the power consumption forecast. For data analysis, a neural network and a program developed in C # are used, which allows you to use data from the enterprise SQL server from exceptions and columns. The result of the neural network was compared with real data on electricity consumption. The data is predicted by the installed equipment to the margin of error.
45

Big Data Management Framework based on Virtualization and Bitmap Data Summarization

Su, Yu 18 May 2015 (has links)
No description available.
46

Modélisation multi-physique en génie électrique. Application au couplage magnéto-thermo-mécanique / Multiphysics modeling in electrical engineering. Application to a magneto-thermo-mechanical model

Journeaux, Antoine 18 November 2013 (has links)
Cette thèse aborde la problématique de la modélisation multiphysique en génie électrique, avec une application à l’étude des vibrations d’origine électromagnétique des cages de développantes. Cette étude comporte quatre parties : la construction de la densité de courant, le calcul des forces locales, le transfert de solutions entre maillages et la résolution des problèmes couplés. Un premier enjeu est de correctement représenter les courants, cette opération est effectuée en deux étapes : la construction de la densité de courant et l’annulation de la divergence. Si des structures complexes sont utilisées, l’imposition du courant ne peut pas toujours être réalisée à l’aide de méthodes analytiques. Une méthode basée sur une résolution électrocinétique ainsi qu’une méthode purement géométrique sont testées. Cette dernière donne des résultats plus proches de la densité de courant réelle. Parmi les nombreuses méthodes de calcul de forces, les méthodes des travaux virtuels et des forces de Laplace, considérées par la littérature comme les plus adaptées au calcul des forces locales, ont été étudiées. Nos travaux ont montré que bien que les forces de Laplace sont particulièrement précises, elles ne sont pas valables si la perméabilité n’est plus homogène. Ainsi, la méthode des travaux virtuels, applicable de manière universelle, est préférée. Afin de modéliser des problèmes multi-physiques complexes à l’aide de plusieurs codes de calculs dédiés, des méthodes de transferts entre maillages non conformes ont été développées. Les procédures d’interpolations, les méthodes localement conservatives et les projections orthogonales sont comparées. Les méthodes d’interpolations sont réputées rapides mais très diffusives tandis que les méthodes de projections sont considérées comme les plus précises. La méthode localement conservative peut être vue comme produisant des résultats comparables aux méthodes de projections, mais évite l’assemblage et la résolution de systèmes linéaires. La modélisation des problèmes multi-physiques est abordée à l’aide des méthodes de transferts de solutions. Pour une classe de problème donnée, l’assemblage d’un schéma de couplage n’est pas unique. Des tests sur des cas analytiques sont réalisés afin de déterminer, pour plusieurs types de couplages, les stratégies les plus appropriées.Ces travaux ont permis une application à la modélisation magnéto-mécanique des cages de développantes est présentée. / The modeling of multi-phycics problems in electrical engineering is presented, with an application to the numerical computation of vibrations within the end windings of large turbo-generators. This study is divided into four parts: the impositions of current density, the computation of local forces, the transfer of data between disconnected meshes, and the computation of multi-physics problems using weak coupling, Firstly, the representation of current density within numerical models is presented. The process is decomposed into two stages: the construction of the initial current density, and the determination of a divergence-free field. The representation of complex geometries makes the use of analytical methods impossible. A method based on an electrokinetical problem is used and a fully geometrical method are tested. The geometrical method produces results closer to the real current density than the electrokinetical problem. Methods to compute forces are numerous, and this study focuses on the virtual work principle and the Laplace force considering the recommendations of the literature. Laplace force is highly accurate but is applicable only if the permeability is uniform. The virtual work principle is finally preferred as it appears as the most general way to compute local forces. Mesh-to-mesh data transfer methods are developed to compute multi-physics models using multiples meshes adapted to the subproblems and multiple computational software. The interpolation method, a locally conservative projection, and an orthogonal projection are compared. Interpolation method is said to be fast but highly diffusive, and the orthogonal projections are highly accurate. The locally conservative method produces results similar to the orthogonal projection but avoid the assembly of linear systems. The numerical computation of multi-physical problems using multiple meshes and projections is then presented. However for a given class of problems, there is not an unique coupling scheme possible. Analytical tests are used to determine, for different class of problems, the most accurate scheme. Finally, numerical computations applied to the structure of end-windings is presented.
47

Metoda za povezivanje mernog sistema i računarapomoću konverzije podataka iz I2S u TCP/IP protokol / Method for Connecting Measuring System With Computer by Converting Data From I2S to TCP/IP Protocol

Sakal Tibor 01 June 2017 (has links)
<p>Ova doktorska disertacija predstavlja istraživački rad sproveden sa ciljem da re&scaron;i problem koji se odnosi na realizaciju povezivanja laboratorijskog, medicinskog mernog uređaja sa personalnim računarom. Rezultat istraživačkog rada je op&scaron;ta metoda koja obezbeđuje efikasnu konverziju podataka I2S protokola u TCP/IP protokol.</p> / <p>This doctoral thesis presents the research work carried out in order to solve a practical problem, the realization of a connection between a medical measuring device and a personal computer. The result of the research is a general method that provides efficient data conversion from the I2S protocol to the TCP/IP protocol.</p>
48

Overset adaptive strategies for complex rotating systems

Shenoy, Rajiv 22 May 2014 (has links)
The resolution of the complex physics of rotating configurations is critical for any engineering analysis that requires multiple frames of reference. Two well-known applications are in the rotorcraft and wind energy industries. Rotor wake impingement from rotor-fuselage and wind turbine-tower interactions impact structural and acoustic characteristics. Additionally, parasite drag resulting from rotorcraft hubs may result in severe limitations on forward flight vehicle performance. Complex turbulent wakes from rotors and hubs impinging on downstream empennage can create adverse aeroelastic behavior and can affect handling qualities. Numerical simulations of these flows require state-of-the-art Navier Stokes methods using dynamic overset grids. However, many current methods typically used in industry result in wakes that dissipate essential features. In order to address these concerns, two advancements are introduced in this thesis. Feature-based grid adaptation on dynamic overset grids has been developed and demonstrated with an unstructured Navier Stokes solver. The unique feature of the adaptation technique is that it is applied globally on the overset grid system except within the boundary layer. In concert with grid adaptation, an efficient parallelized search algorithm for solution interpolation over massively distributed systems has been created. This results in cost-effective interpolation that retains the numerical order of accuracy and has been verified in both space and time. The improvements have been demonstrated for rotor-fuselage interaction and a generic rotating hub. Detailed analysis of convergence of the methodology and sensitivity of the results to relevant parameters have also been included.
49

Optimization of Remote ServiceSolution for large installations : Wireless LAN and WAN for ABB Robotics

Stenbom, Håkan January 2011 (has links)
This report describes a thesis work carried out at ABB Robotics in Västerås. The objective of this thesis is to find technologies  and equipments  for wireless data transfer  suitable for the present and future needs of ABB Robotics Remote Service for large installations in industrial environments. ABB Robotics has a Remote Service solution to securely gather information from robots, manage alarms and potentially execute remote commands by ABB Robotics. This solution consists of an intelligent Service  Box plugged to the robot. This  Service Box is also connected through GPRS or directly through Internet to create a secure VPN connection to a central Remote Service  server. The Remote Service Box is well  suited  for small customers with  1-10 robots with plug  and play installation, but show limitations at a larger scale of deployment  due to equipment costs,  network and installation complexity. A new Service Box is planned that will accommodate future added functionality to Remote Service. This Service Box will require new network solutions as the added functionality  is depending on a higher bandwidth than the GPRS networks can deliver. I have surveyed most existing  wireless  networking technologies  and  analyzed  them  withrespect  to function, cost and availability which provide a knowledge base that makes it possible to find  suitable  solutions. When the most suitable technologies are identified a survey was performed to find equipments that meet the requirements at the lowest cost. A new hierarchical network topology is proposed  that will lead to cost savings by replacing multiple WAN connections in the present solution with  a network switch and  single WAN connection to Internet. As manufacturers of network equipments for industrial environments are relatively few, alternative solutions were also investigated in order to find the most cost effective solutions. The  proposed  network topology together with the data from the surveys lead to recommendations on using Wi-Fi  in the wireless LAN and  a  3G mobile  network for the WAN connection to Internet, as well as recommendations on alternative network equipments that  potentially  can  lead to substantial savings when the new network solutions are implemented.
50

Conceptual Design of a South Pole Carrier Pigeon UAV

Dlima, Kendrick M 01 June 2020 (has links)
Currently, the South Pole has a large data problem. It is estimated that 1.2 TB of data is being produced every day, but less than 500 GB of that data is being uploaded via aging satellites to researchers in other parts of the world. This requires those at the South Pole to analyze the data and carefully select the parts to send, possibly missing out on vital scientific information. The South Pole Carrier Pigeon will look to bridge this data gap. The Carrier Pigeon will be a small unmanned aerial vehicle that will carry a 30 TB solid-state hard drive from the South Pole to various destinations in the Southern Hemisphere, but it has been designed to y to Christchurch, New Zealand. This 87 lb. UAV will be able to y 3,650 nmi. up to 25,000 ft., using a 5.7 hp. engine. It will feature an de-icing system on the leading edge of its 8 ft. span wing to allow it to y through cold, moist climates. It will have a 39 in. long fuselage with a tail boom of 33 in. The aircraft has been designed to be made out of composites, thus reducing both the weight of the aircraft as well as its drag. It has been designed to come apart in order to be shipped successfully to the South Pole. There, it will be assembled and launched via a custom pneumatic launcher. It will y autonomously to 15,000 ft. and cruise climb throughout the flight to 25,000 ft., before descending to its destination. There, it will be caught by a net restraint system, where the hard drive will be extracted. The Carrier Pigeon is truly a unique vehicle for its size, range, and robustness.

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