• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 104
  • 58
  • 30
  • 22
  • 12
  • 11
  • 9
  • 8
  • 6
  • 6
  • 5
  • 3
  • 2
  • 2
  • 2
  • Tagged with
  • 302
  • 302
  • 56
  • 47
  • 47
  • 45
  • 41
  • 36
  • 35
  • 34
  • 29
  • 28
  • 28
  • 28
  • 27
  • 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.
261

Sportovní a společenské centrum-rekonstrukce / Sports and social centre - reconstruction

Štěpančík, Ondřej January 2016 (has links)
This thesis solves reconstruction of the community center in the village Částkov where work was the subject of energy-efficient and adapt the layout of buildings a new purpose use. It is designed thermal insulation of the building envelope, exchanging heat source with respect to the use of renewable energy and static security buildings in the form of newly built ceiling construction of the supporting steel rolled profiles and reinforced concrete slabs. The building will serve the public amenities and is necessary to ensure barrier-free movement of people into the building and inside it. The second part is to solve the surrounding buildings. It is designed multifunctional sports and sports areas of social security. The basis for the development of the scientific literature, technical standards, regulations and current studies at the Faculty of Civil Engineering.
262

Vliv provedení zateplení objektu rodinného domu v obci Újezd u Rosic na výdaje spojené s provozem této nemovitosti / The impact of executing new thermal insulation on a single-family house village Újezd u Rosic on the expenses associated with the operation of this real estate

Stromecký, Jiří January 2016 (has links)
The influence of the thermal insulation of a family house in the village of Újezd u Rosic and the expenses related with the operation of this property. Brief characteristics of the task and its challenges: The task will be to work on a proposal to insulate the chosen property. Based on this proposal, then evaluate the difference in cost for the operation of the property before and after insulation. The work will also evaluate the economic return on the investments made.
263

Vliv provedení zateplení rodinného domu na výdaje spojené s jeho provozem / The impact of executing new thermal insulation on a single-family house on the expenses associated with its operation

Labounek, Martin January 2016 (has links)
This diploma thesis deals with insulation of the house and it's costs. First part relates to the developement of the construction, the current trends in the construction of houses, prices of energy and heating options. Next part relates with insulation system ETICS, the way of it's implementation and thermal assessment with basic names. Thermal insulation is designed in six variants. The work includes thermal assessment in original condition and the assessment of new condition modified by adding thermal insulation with it's economic return. In conclusion, the diploma thesis evaluates the payback period of insulation.
264

Genetický návrh klasifikátoru s využítím neuronových sítí / Neural Networks Classifier Design using Genetic Algorithm

Tomášek, Michal January 2016 (has links)
The aim of this work is the genetic design of neural networks, which are able to classify within various classification tasks. In order to create these neural networks, algorithm called NeuroEvolution of Augmenting Topologies (also known as NEAT) is used. Also the idea of preprocessing, which is included in implemented result, is proposed. The goal of preprocessing is to reduce the computational requirements for processing of benchmark datasets for classification accuracy. The result of this work is a set of experiments conducted over a data set for cancer cells detection and a database of handwritten digits MNIST. Classifiers generated for the cancer cells exhibits over 99 % accuracy and in experiment MNIST reduces computational requirements more than 10 % with bringing negligible error of size 0.17 %.
265

Automatické strojové metody získávání znalostí z multimediálních dat / Automatic Machine Learning Methods for Multimedia Data Analysis

Mašek, Jan January 2016 (has links)
The quality and efficient processing of increasing amount of multimedia data is nowadays becoming increasingly needed to obtain some knowledge of this data. The thesis deals with a research, implementation, optimization and the experimental verification of automatic machine learning methods for multimedia data analysis. Created approach achieves higher accuracy in comparison with common methods, when applied on selected examples. Selected results were published in journals with impact factor [1, 2]. For these reasons special parallel computing methods were created in this work. These methods use massively parallel hardware to save electric energy and computing time and for achieving better result while solving problems. Computations which usually take days can be computed in minutes using new optimized methods. The functionality of created methods was verified on selected problems: artery detection from ultrasound images with further classifying of artery disease, the buildings detection from aerial images for obtaining geographical coordinates, the detection of materials contained in meteorite from CT images, the processing of huge databases of structured data, the classification of metallurgical materials with using laser induced breakdown spectroscopy and the automatic classification of emotions from texts.
266

Research on efficient driving method of heavy hydraulic excavator boom

Xia, Lianpeng, Quan, Long, Ge, Lei, Hao, Yunxiao, Zhao, Bin, Li, Bin 25 June 2020 (has links)
There is a lot of gravitational potential energy waste when hydraulic excavators work, which seriously affects the efficiency of the whole machine and produces a large amount of emissions. In order to reduce the energy consumption and emissions of large hydraulic excavators which the boom is driven by two hydraulic cylinders, an integrated drive and potential energy recuperation principle is proposed. In the implementation, the original two-chamber hydraulic cylinders are replaced by three-chamber hydraulic cylinders with energy storage chambers, and the energy storage chambers are directly connected with the hydraulic accumulator. The dead weight of the working device is balanced by the initial hydraulic pressure of the hydraulic accumulator, and the gravitational potential energy is directly recuperated. A digital prototype is established for the simulation work to verify the energy-saving effect. Then a test prototype is constructed according to the simulation work. The standard 90° loading duty cycle tests show that compared with the standard hydraulic excavators of the same type, in the case of meeting the same digging force, the working efficiency of the excavator increases by 20.7% and the fuel consumption decreases by 17.1%. In terms of 8 hours of work per day, a single excavator can save fuel up to 47 L per day and reduce carbon dioxide emissions by 123.6 kg.
267

Combinations of energy saving measures in pneumatics

Boyko, Vladimir, Weber, Jürgen 26 June 2020 (has links)
Within a production machine, various electromechanical and pneumatic structures can be used for drive tasks. As these drive technologies can often replace each other, the energy efficiency, performance and TCO of pneumatic drives must be permanently enhanced to remain competitive. There is a large number of known measures for the reducing their energy consumption, e.g. minimizing of filling volumes, energy saving circuits etc. However, these measures are mainly considered separately and the possible overall energy saving effect resulting from their combination is rarely taken into account. The main goal of this paper is therefore to explore the possible combinations of pneumatic energy saving measures and their cumulative saving effect. Due to the fact that some measures are mutually exclusive (e.g. a general pressure reduction in properly sized drive), each combination should be considered separately. To evaluate their efficiency plausibly, a comprehensive assessment is required that contains both the total cost of ownership analysis (TCO) and a mechanical properties assessment. The presented comprehensive approach of the task analysis can serve as example of how an optimal drive configuration for the specific task can be found, thus creating a basis for solving constructive challenges in designing of pneumatic automation systems.
268

Ordonnancement et routage pour l'augmentation de la durée de vie dans les réseaux de capteurs sans fil / Scheduling and routing for increasing the network lifetime in wireless sensor networks

Lassouaoui, Lilia 06 July 2018 (has links)
Les réseaux de capteurs sans fil (RCSF) sont très largement utilisés dans divers domaines d'applications civiles et militaires, comme la surveillance de champs de bataille, la détection de phénomène environnementaux, ou encore les bâtiments intelligents. Cependant, les réseaux de capteurs sans fil sont caractérisés par de fortes limitations au niveau de l'énergie disponible et des communications radio. Les travaux réalisés dans cette thèse visent à proposer des solutions garantissant une certaine qualité de service dans le contexte des réseaux de capteurs sans fil. La première partie concerne la couche liaison de données avec l'objectif d'augmenter la durée de vie du réseau. L'accès au médium sans fil est analysé et modélisé sous la forme d'un problème d'ordonnancement des liens de communication, tenant compte des collisions. Nous étudions alors la complexité de ce problème. Une approche distribuée et tolérante aux défaillances avec garantie de performance est proposée (SS-DD2EC) pour résoudre ce problème. La seconde partie de la thèse concerne le routage des messages à l'aide du protocle IPv6 Routing Protocol for Low-Power and Lossy Network (RPL). Tout d'abord, un comparatif entre les différentes métriques de routage existantes pour l'optimisation de l'énergie consommée a été mené. En plus de la durée de vie, les critères de fiabilité et de latence de bout-en-bout sont considérés pour évaluer ces métriques. Enfin, deux nouvelles métriques (R_MinMax et R_Delai) ont été proposées pour RPL permettant d'atteindre des gains significatifs par rapport à l'état de l'art. La première ne tient compte que des critères de consommation d'énergie et de fiabilité, alors que la seconde intègre en plus la latence de bout-en-bout. / Wireless sensor networks (RCSF) is a technology that has a wide range of civil or military applications, including battlefield monitoring, environmental monitoring or smart city. However, WSN are characterized by high limitations in terms of energy (battery-operated nodes) and wireless links (low power and lossy links). The work done in this PhD thesis aims to provide solutions that guarantee a certain quality of service in the context of wireless sensor networks. The first part of this work concerns the medium access control layer with the aim of increasing the lifetime of the network. The access to the wireless medium is analyzed and modeled as a link scheduling problem, taking into account collisions. First, a study of the complexity of this problem is carried out, then a distributed and fault-tolerant approach with guaranteed performance is proposed (SS-DD2EC) to solve this problem. The second part is about message routing with the IPv6 Routing Protocol for Low Power and Lossy Network (RPL). First of all, a comparison between the various existing routing metrics for the optimization of the energy consumed has been carried out. In addition of lifetime, the reliability and end-to-end latency criteria are considered for evaluating these metrics. Then, two new RPL metrics (R_MinMax and R_Delai) were proposed, achieving significant gains over the state of the art. The first one only considers the energy consumption and reliability, while the second one takes also into account the end-to-end latency.
269

Fuktrelaterade risker vid lågenergikonstruktion i lättbetong : En studie av ett nyproducerat passivhus / Moisture related risks with aerated concrete in low energy constructions : A study of a newly produced passive house

Jansson, Sebastian, Niklasson, Erik January 2014 (has links)
Trenden i byggbranschen är att efterfrågan på täta, energisnåla byggnader ökar. Passivhus och andra lågenergikonstruktioner blir vanligare och vanligare. Riskerna med att bygga in organiskt material som trä i dessa konstruktioner har fått branschen att börja titta på alternativa material. Lättbetong är ett material som både har bärande och isolerande egenskaper. Dessutom är det inte organiskt vilket gör det okänsligt för mikrobiell påväxt. Det som är intressant med lättbetong, ur fuktsynpunkt, är att materialet levereras från tillverkare med en stor mängd byggfukt. Våren 2014 färdigställde Bollnäs Bostäder passivhus- projektet Sundsbro i Bollnäs, där lättbetong ingår i utfackningsväggarna. Sett inifrån består väggen av ett tunt lager kc-puts, lättbetong, cellplast, mineralull, kc-baserad grovputs och ytputs. I detta arbete användes projektet i Bollnäs som referensobjekt och en risk- och känslighetsanalys av väggkonstruktionen utfördes. Arbetet utreder risken för fuktrelaterade problem med väggen vid de extra uttorkningsinsatser som vidtogs i referensobjektet och vid normala uttorkningsbetingelser. Vidare utreds vilka parametrar som är viktiga för väggens fuktfunktion och vad man behöver tänka på när man projekterar och bygger i lättbetong. Arbetet har genomförts i samarbete med AK-Konsult Indoor Air AB och deras senior konsult Anders Kumlin. Fuktberäkningsprogrammet WUFI Pro 5.3 har använts för simuleringar. Beräkningarna gjordes endimensionellt på väggkonstruktionen. Resultaten med den ökade uttorkning som utfördes i referensobjektet visar inget högre fuktinnehåll längst ut i väggen på grund av byggfukt från lättbetongen som vandrar utåt. Farhågan var att så skulle kunna ske och att det skulle kunna leda till mögelproblem. Däremot visar resultaten att bygg-fukt från putsen kan fukta upp mineralullen. Det finns dock inga kända skadefall av detta slag och därför dras ändå slutsatsen att konstruktionen är riskfri. Tack vare en förutseende fukt-projektering och väl utförd uttorkning eliminerades risken för mögel. Hade inte dessa åtgärder vidtagits så visar resultaten att en liten mängd byggfukt hade kunnat vandra utåt och kondensera i mineralullen under första vintern. Då hade det funnits risk för mikrobiell påväxt. Detta visar att det är av största vikt att utföra en noggrann fuktprojektering vid byggnation av välisolerade hus i allmänhet och i synnerhet när lättbetong används. Lyckligtvis gjordes detta på ett bra sätt i referensprojektet. Känslighetsanalysen visar att isoleringens diffusionstäthet är avgörande för hur stor del av bygg-fukten som kan vandra utåt och därmed hur stor risken för problem blir. Lägre täthet ger större risk och högre täthet reducerar risken. Resultaten visar också att det är viktigt att inte montera täta skikt på insidan för tidigt. Den allmänna rekommendationen från leverantör är att lättbetongen skall torkas till 15 % fuktkvot på 50 millimeters djup innan målning och tapetsering på insida vägg får ske. Studien visar att detta är ett för högt fukttillstånd om det skikt som appliceras på insida vägg är tätt. Lättbetongen bör torkas till 5 % på 50 millimeters djup innan helt täta skikt kan monteras utan mögelrisk. / The trend in the construction industry is that the demand for tight, energy-saving buildings is rising. Passive houses and low energy constructions are becoming more and more common. The risk with using organic material in this type of constructions has made the industry look at alternative materials. Aerated concrete is a material that has both load-bearing and insulating properties. In addition to that it is not organic, which makes it insensitive to microbial growth. What is interesting with aerated concrete, from a moisture point of view, is that the material is delivered from the producer with a large amount of construction moisture. In the spring of 2014, the passive-house project Sundsbro in Bollnäs with aerated concrete in the wall construction, was finished by Bollnäs Bostäder. In this study the project in Bollnäs was used as reference object and a risk- and sensitivity analysis was made. The study examines the risk of moisture related problems with the wall construction during normal dehydration conditions and after the increased dehydration efforts that were taken in the reference project. The study also examines which parameters are important for the moisture function of the wall construction and what you need to think about when you project and build with aerated concrete. The job has been done in cooperation with AK-Konsult Indoor Air AB and their senior consultant Anders Kumlin. The moisture calculation program WUFI Pro 5.3 has been used for simulations. The results with the increased dehydration that was used in the reference project show no increased moisture content in the outer parts of the construction due to construction moisture from the concrete that wanders outwards. The concern was that so could happen and that it would lead to mould problems. However the results show that construction moisture from the exterior plaster can moisten the mineral wool. There are no known damage cases of this sort and therefore the conclusion is that the construction is free of risk. Thanks to a foreseeing moisture projection and a well performed dehydration the risk of mould was eliminated. If these measures would not have been taken, the results show that a small amount of construction moisture could have wandered outwards and condensed inside the mineral wool during the first winter. Then there would have been a risk of microbial growth. This shows that it is very important to carry out a detailed moisture projection when constructing well insulated houses in general and when using aerated concrete in particular. Fortunately this was properly done in the reference project. The sensitivity analysis shows that the diffusion resistance of the insulation decides how much of the construction moisture that can wander outwards and consequently the size of the problem risk. Results also show that it is crucial not to apply sealing layers on the inside of the wall too early. The general recommendation from the supplier is that the aerated concrete should be dried to 15 % moisture ratio on 50 millimeter depth before painting and paper hanging on the interior surface of the wall can be done. The study shows that the concrete still is too damp at that stage if the layer applied on the inside of the wall is impermeable. The concrete should be dried down to 5 % moisture ratio before sealing layers can be applied without mould risk.
270

Advanced intelligent lighting system for boosting personal comfort and energy saving of workspaces / ワークスペースの個別的快適性とエネルギー節約を増進する先端的知的照明システム / ワークスペース ノ コベツテキ カイテキセイ ト エネルギー セツヤク オ ゾウシン スル センタンテキ チテキ ショウメイ システム

Mohammed Awad Hajjaj 22 March 2021 (has links)
本論文は,知的照明システムの改良に関わるものであり,従来の課題であった色温度の実現精度の向上と高価な色温度センシング機材を無くす方法ならびにそれらの最適制御法,これまで不明であったシステムがもたらす省エネルギー性に関する詳細な解析方法を提案し,これらの提案手法の有効性を検証するため新たに改良した知的照明システムを用いて実験を行い,それらの手法の有効性を確認した. / An advanced intelligent lighting system has been proposed and introduced to provide a comfortable personal lighting environment for the workplace using the evaluation and biological information of workers. The research studies the appropriate perspectives of using the intelligent lighting system as a solution of the smart design in the office workspace. In the first part, the research paper has utilized the computerized system and the optimization method to generate the lighting automatically instead of using the sensing devices. The second part is related to energy consumption. The illuminance has been distributed based on the individual preference available of each user inside the office. / 博士(工学) / Doctor of Philosophy in Engineering / 同志社大学 / Doshisha University

Page generated in 0.0599 seconds