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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.
11

Energieffektivisering genom fastighetsautomation : Grundläggande teori, svensk marknadsöversikt och exempel på verklig installation

Johansson, Ola, Ulverås, Mikael January 2016 (has links)
För att uppnå Sveriges miljömål begränsad klimatpåverkan behöver åtgärder göras för att minska energianvändningen inom bostads- och servicesektorn, vilken stod för drygt en tredjedel av Sveriges totala energianvändning år 2014. Dålig styrning av värme-, ventilations- och kylsystem är ofta en bidragande orsak till onödigt hög energianvändning inom hushåll och lokalbyggnader. Med hjälp av fastighetsautomation samlas byggnadens tekniska system i ett styr- och övervakningssystem, vilket kan användas för att optimera styrningen. Dock är marknaden för fastighetsautomation dåligt kartlagd och information saknas angående styrsystemens funktioner och användningsområden. Rapporten inleds med grundläggande teori för att skapa ökad förståelse för senare delar. Därefter har en undersökning gjorts för ett antal företags styrsystem i syfte att klargöra dess funktioner, användningsområden samt vilken energibesparing styrsystemen ger upphov till. I rapporten beskrivs också tillvägagångssättet för en verklig installation i lokalbyggnaden Kv Slottet 4 och hur energianvändning samt inneklimat har påverkats efter att styrsystemet installerats. Resultatet för den svenska marknadsöversikten visar på att fastighetsautomation är etablerat inom byggnadstyperna flerbostadshus och lokalbyggnader medan småhus är en outforskad marknad. Vanliga funktioner som implementeras i styrsystem är drifttidsstyrning, prognosstyrning och effektbegränsning. Undersökningen har visat att fastighetsautomation ger upphov till energibesparingar på i snitt 10 – 40 %. Besparingen varierar dock och beror på flera faktorer som byggnadstyp, geografisk placering och tidigare styrning. Företagen använder också olika metoder för att beräkna energibesparingen varför det är problematiskt att rättvist jämföra besparingen för olika styrsystem. Energibesparingen för de olika byggnadstyperna och installationssystemen har i många fall varit svåra att få tillgång till. Generellt gäller att de företag som tillhandahåller obligatoriskt driftavtal har bättre koll på den besparing som styrsystemet ger upphov till. I examensarbetet har fyra företag kartlagts men för en mer djupgående analys över den svenska marknaden bör fler företag undersökas. Efter installationen av det automatiska styrsystemet Ecopilot® på Kv Slottet 4 erhölls en värmeenergibesparing för vald period på upp till 20,6 MWh, vilket motsvarar en procentuell besparing på 53 %. Energibesparingen varierar dock till viss del beroende på vilken beräkningsmetod som används. Byggnadens totala elbesparing uppgick till 6,5 MWh, vilket motsvarar 20 % minskning av elanvändningen för undersökt period. Den beräknade energibesparingen kan inte helt tillskrivas Ecopilot® eftersom ett annat driftfall rådde under jämförd period än det som var precis innan installationen. Via styrsystemets gränssnitt kunde emellertid en sänkt energianvändning härledas till Ecopilot®. Bland annat tack vare effektivare reglering, samkörning av installationssystem, effektivare värmeåtervinning, sänkta ventilationsflöden samt lägre inomhus- och flödestemperaturer. Intervjuer med verksamma personer i byggnaden påvisar att ingen skillnad har märkts på inomhusklimatet före och efter installationen av Ecopilot®, varken med avseende på det termiska klimatet eller på luftkvaliten. För större säkerhet gällande styrsystemets inverkan på inomhusklimatet och energianvändningen bör en längre tidsperiod utvärderas. / Sweden has a number of environmental objectives, of which one is reduced climate impact. To achieve this goal measures have to be taken in order to reduce building energy use in residential and services sectors, sectors that accounted for over one third of Sweden’s total energy use in 2014. Poor regulation of heating, ventilation, and air conditioning (HVAC) is a common reason for often unnecessary high energy use in residential buildings and non-residential premises. Building automation integrates the buildings technical systems, such as HVAC, into one centralized system for monitoring and controlling, which then can be used to optimize the regulation for these systems. The market is however poorly mapped and information is missing regarding functions and area of use for these control systems. This report begins with a description of basic theory that is relevant for understanding parts later on. An analysis has then been made for a number of different building automation systems to clarify their functions, area of use, and potentials in energy savings. The report also describes the procedure for a real installation on Kv Slottet 4 and how the energy use and indoor climate has been affected after the building automation system has been installed. Results regarding the Swedish market overview shows that building automation is established in apartment buildings and non-residential premises while building automation is still unused in smaller houses. Some of the most common functions that are implemented in control systems are time clock operation, forecast control and power limitation. The analysis has shown that building automation can lead to energy savings between 10 to 40 %. The size of the saved energy depends on a number of factors like type of building, geographical location and former regulation of HVAC. The building automation companies are using different methods to calculate the energy saving why it is a problem to fairly compare different control systems. The information on energy savings for different type of buildings and technical systems are in many cases hard to get hold of. Generally speaking, the companies that provide mandatory agreements for operating the control system have more detailed information regarding energy savings. Four different companies were covered in this report. More companies should be mapped in order to make a more profound analysis. After the installation of Ecopilot® on Kv Slottet 4, a heat reduction of up to 20.6 MWh for the chosen period of time was achieved. That corresponds to a relative energy saving of 53 %. The energy saving varies depending on what method is used for calculation. The buildings total energy savings for electricity was 6.5 MWh, which corresponds to a 20 % reduction. The calculated energy saving is not all due to the building automation system but there has been some reduction. Ecopilot® has lowered the energy use by more efficient regulation, co-operating heating and cooling, more efficient heat recovery, lowered ventilation flows, and lowered temperatures. No change in indoor climate has been noticed by the people that were interviewed. The control system should be evaluated for a longer period of time to ensure how much it affects the indoor climate and the energy use in the building.
12

Freeway Travel Time Prediction Using Data from Mobile Probes

Izadpanah, Pedram 08 November 2010 (has links)
It is widely agreed that estimates of freeway segment travel times are more highly valued by motorists than other forms of traveller information. The provision of real-time estimates of travel times is becoming relatively common in many of the large urban centres in the US and overseas. Presently, most traveler information systems are operating based on estimated travel time rather than predicted travel time. However, traveler information systems are most beneficial when they are built upon predicted traffic information (e.g. predicted travel time). A number of researchers have proposed different models to predict travel time. One of these techniques is based on traffic flow theory and the concept of shockwaves. Most of the past efforts at identifying shockwaves have been focused on performing shockwave analysis based on fixed sensors such as loop detectors which are commonly used in many jurisdictions. However, latest advances in wireless communications have provided an opportunity to obtain vehicle trajectory data that potentially could be used to derive traffic conditions over a wide spatial area. This research proposes a new methodology to detect and analyze shockwaves based on vehicle trajectory data and will use this information to predict travel time for freeway sections. The main idea behind this methodology is that average speed on a section of roadway is constant unless a shockwave is created due to change in flow rate or density of traffic. In the proposed methodology first the road section is discretized into a number of smaller road segments and the average speed of each segment is calculated based on the available information obtained from probe vehicles during the current time interval. If a new shockwave is detected, the average speed of the road segment is adjusted to account for the change in the traffic conditions. In order to detect shockwaves, first, a two phase piecewise linear regression is used to find the points at which a vehicle has changed its speed. Then, the points that correspond to the intersection of shockwaves and trajectories of probe vehicles are identified using a data filtering procedure and a linear clustering algorithm is employed to group different shockwaves. Finally, a linear regression model is applied to find propagation speed and spatial and temporal extent of each shockwave. The performance of this methodology was tested using one simulated signalized intersection, trajectories obtained from video processing of a section of freeway in California, and trajectories obtained from two freeway sections in Ontario. The results of this thesis show that the proposed methodology is able to detect shockwaves and predict travel time even with a small sample of vehicles. These results show that traffic data acquisition systems which are based on anonymously tracking of vehicles are a viable substitution to the tradition traffic data collection systems especially in relatively rural areas.
13

Freeway Travel Time Prediction Using Data from Mobile Probes

Izadpanah, Pedram 08 November 2010 (has links)
It is widely agreed that estimates of freeway segment travel times are more highly valued by motorists than other forms of traveller information. The provision of real-time estimates of travel times is becoming relatively common in many of the large urban centres in the US and overseas. Presently, most traveler information systems are operating based on estimated travel time rather than predicted travel time. However, traveler information systems are most beneficial when they are built upon predicted traffic information (e.g. predicted travel time). A number of researchers have proposed different models to predict travel time. One of these techniques is based on traffic flow theory and the concept of shockwaves. Most of the past efforts at identifying shockwaves have been focused on performing shockwave analysis based on fixed sensors such as loop detectors which are commonly used in many jurisdictions. However, latest advances in wireless communications have provided an opportunity to obtain vehicle trajectory data that potentially could be used to derive traffic conditions over a wide spatial area. This research proposes a new methodology to detect and analyze shockwaves based on vehicle trajectory data and will use this information to predict travel time for freeway sections. The main idea behind this methodology is that average speed on a section of roadway is constant unless a shockwave is created due to change in flow rate or density of traffic. In the proposed methodology first the road section is discretized into a number of smaller road segments and the average speed of each segment is calculated based on the available information obtained from probe vehicles during the current time interval. If a new shockwave is detected, the average speed of the road segment is adjusted to account for the change in the traffic conditions. In order to detect shockwaves, first, a two phase piecewise linear regression is used to find the points at which a vehicle has changed its speed. Then, the points that correspond to the intersection of shockwaves and trajectories of probe vehicles are identified using a data filtering procedure and a linear clustering algorithm is employed to group different shockwaves. Finally, a linear regression model is applied to find propagation speed and spatial and temporal extent of each shockwave. The performance of this methodology was tested using one simulated signalized intersection, trajectories obtained from video processing of a section of freeway in California, and trajectories obtained from two freeway sections in Ontario. The results of this thesis show that the proposed methodology is able to detect shockwaves and predict travel time even with a small sample of vehicles. These results show that traffic data acquisition systems which are based on anonymously tracking of vehicles are a viable substitution to the tradition traffic data collection systems especially in relatively rural areas.
14

Disentangling sociomateriality : an exploration of remote monitoring systems in interorganizational networks / Att dekonstruera sociomaterialitet : En undersökning av fjärrdiagnostiksystem i interorganisatoriska nätverk

Westergren, Ulrika H. January 2011 (has links)
Firmly placed in an industrial setting, this research explored the introduction of remote monitoring technology into three different organizational contexts. By following these organizations over time, starting with their intention to invest in remote monitoring systems (RMS), there was a unique opportunity to witness their processes and to gain an insight into the intricacies of information technology (IT) and organizational transformation. The main question that this research sought to answer was thus: How is IT implicated in the remote monitoring of industrial equipment? Previous information systems research has been accused of not paying enough attention to the material, that is, of not being specific about technology. This research adopted a sociomaterial perspective, thus recognizing the constitutive entanglement of the material and the social, and thereby acknowledging their mutual dependency. However, in order to provide specific insights about the material, an analytical disentanglement was performed, by extending the concept of agency from a focus on “the what” to include “the how”. Change was thus studied by not only asking what the nature of change is and who or what causes change to occur, but by also tracing how change is enacted, thus capturing both material and social agency as well as tracing their entanglement. This research employed a broad approach, designed to provide a profound and extensive account of the studied phenomenon. Consequently, the thesis explored value creation, sourcing routines, partnership formation and innovative practices all related to remote diagnostics design and use. In addition, the research was qualitative and used interpretive case studies as the main methodology. A composite finding of this research is that an RMS, with its ability to collect, transmit, store, and analyze specific contextual information across time and space, provides opportunities for boundary-spanning activities manifested as the formation of interorganizational networks. Furthermore, by tracing the information capabilities of the IT, and by being specific about the material, it has been possible to explore how RMSs have the potential to influence both organizational form and content. Through the examination of RMSs within interorganizational networks and as a part of value creation practices, this research has also shown how the organizational form and content have the potential to influence RMSs; their design, use, and material affordances. This research also placed focus on the importance of trust and has shown that trust in technology is established through trust in people.
15

Εντοπισμός θέσης κινούμενων ατόμων σε πλατφόρμα σταθμού μετρό

Παπαδάκης, Παναγιώτης 05 January 2011 (has links)
Τα τελευταία χρόνια υπάρχει μια αυξημένη χρήση των κλειστών συστημάτων παρακολούθησης, είτε αυτά αφορούν την επιτήρηση κλειστών χώρων για λόγους ασφάλειας, είτε για παρακολούθηση της κυκλοφορίας σε δρόμους αυξημένης κυκλοφορίας ή ακόμα και για στατιστικούς λόγους για τον υπολογισμό επισκεπτών σε εμπορικά κέντρα ή διερχόμενων οχημάτων ή επιβατών σε μέσα μαζικής μεταφοράς, περίπτωση την οποία εξετάζουμε στην παρούσα εργασία. Η μεθοδολογία που αναπτύχτηκε περιλαμβάνει τρία κυρίως στάδια, την αφαίρεση του στατικού φόντου, την ανίχνευση των κινούμενων ατόμων και τον εντοπισμό τους σε όλη διαδρομή τους. / In recent years there has been an increased use of monitoring systems, whether they concern the monitoring of closed areas for security reasons or to monitor traffic on roads with increased traffic or even for statistical purposes to calculate visitors to shopping centers or transit vehicles or passenger to public transportation, which we are examining in this thesis. The methodology was developed in three main stages, removing the static background, the detection of moving people and track them throughout their journey.
16

PSINCO-um programa para calculo da distribuicao de potencia e supervisao do nucleo de reatores nucleares, utilizando sinais de detetores tipo 'SPD'

HIROMOTO, MARIA Y.K. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:43:12Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:56:31Z (GMT). No. of bitstreams: 1 06442.pdf: 6689802 bytes, checksum: 46ba1e2b896e77a4288d24e80ac804ff (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
17

Utilizacao de redes neurais na monitoracao da potencia do reator IEA-R1

ROSSI, ROSA H.P.S. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:45:15Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:32Z (GMT). No. of bitstreams: 1 07285.pdf: 7589238 bytes, checksum: 2dd074efcd927657975875bc5a121997 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
18

Desenvolvimento de um amplificador isolador para analise de sinais dinamicos

DYRJAWOJ, NICOLAU 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:48:25Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:36Z (GMT). No. of bitstreams: 1 08984.pdf: 7815530 bytes, checksum: 2846bcddfb4f882d621deacbf8447f3e (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
19

Análise das variáveis de entrada de uma rede neural usando teste de correlação e análise de correlaçao canônica / Analysis of input variables of an artificial neural network using bivariate correlation and canonical correlation

COSTA, VALTER M. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:34:03Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:52Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
20

Metodologia para monitoracao e diagnostico de vibracao das bombas moto-operadas do circuito primario de refrigeracao do Reator IEA-R1

BENEVENUTI, ERION de L. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:48:58Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:08:23Z (GMT). No. of bitstreams: 1 09626.pdf: 11035558 bytes, checksum: 15aa6dd9cdacdf9c6ea1b493f68aba84 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

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