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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.
101

Online diagnostika obráběcích strojů / Online diagnostics of machine tools

Zářecký, Tomáš January 2020 (has links)
This thesis deals with vibration diagnostics and on-line monitoring systems of several producers. Furthermore, this thesis contains a description and evaluation of measuring the vibrations of the machine tool spindle when machining test samples with different cutting conditions and evaluating the surface quality of test samples.
102

Implementace čárového kódu do výrobního procesu malé firmy / Bar Code Implemamtation to Production Process of Small Factory

Tihon, Karel January 2009 (has links)
Target of my diploma thesis is barcode study and implementation to SMT assembly processes. This thesis contains two main parts. The first one is devoted to basic types of barcodes, reading technologies and industrial process mapping in PCB assembly. The second part is devoted to theoretical proposal and physical realization of system for materials flow monitoring. Barcode is contained in this system. Practical part of this thesis is tested in a company realizing contract manufacturing in PCB assembly - SMT and THT.
103

Äldre personers upplevelser av välfärdsteknik i hemmet - En litteraturöversikt / Older people’s experiences of welfare technology at home - A literature review

Hodén, Ellinor, Holm, Pernilla January 2020 (has links)
Bakgrund: Medelåldern hos den äldre befolkningen har ökat och många äldre har som önskemål att få bo kvar i sina hem. Detta medför ett behov av fler anställda inom äldreomsorgen. Välfärdsteknik kan vara ett hjälpmedel vid äldrevård och betraktas som ett verktyg som kan bidra till att de äldre lättare kan bibehålla sin livskvalitet och självbestämmande.Syfte: Att beskriva de äldre personers upplevelser av välfärdsteknik i hemmet i form av robotar, digitala larm och övervakningssystem.Metod: En litteraturöversikt där resultatet är baserat på 15 vetenskapliga artiklar hämtade från databaserna CINAHL, PubMed och Scopus; nio kvalitativa, två kvantitativa och fyra mixade studier.Resultat: Resultatet delades in i tre huvudkategorier, äldres upplevelser av robotar, äldres upplevelser av digitala larm och äldres upplevelser av övervakningssystem. De äldres upplevelser identifierades vilket genererade i tre underkategorier för varje huvudkategori, acceptans och inställning, säkerhet och trygghet samt integritet och självständighet.Slutsats: Litteraturöversiktens resultat tyder på att välfärdsteknik generellt är accepterat hos den äldre generationen. Välfärdsteknik kan vara ett hjälpmedel som underlättar för de äldre att kunna bo kvar i sina hem. / Background: The average age of the elderly population has increased and many older people have a desire to stay in their homes. This leads to a need of more employees within the elderly care. Welfare technology can be helpful within the elderly care and is considered a tool that helps the elderly to maintain their quality of life and self-determination.Aim: The aim of this study is to describe older people’s experiences of welfare technology in the home with focus on robots, positioning alarm and monitoring system.Method: A literature review where the results are based on 15 scientific articles conducted from CINAHL, PubMed and Scopus database; nine qualitative, three quantitative and three mixed method study.Results: The results were chosen to be divided into three main categories, the elderly's experiences of robots, the elderly's experiences of digital alarms and the elderly's experiences of surveillance systems. The elderly's experiences were identified, which generated in three subcategories for each main categories, acceptance and attitude, safety and security, and integrity and independence.Conclusion: The study indicates that welfare technology is generally accepted by the older generation. Welfare technology can be an aid that makes it easier for the elderly to stay in their homes.
104

Simulative Evaluation of Security Monitoring Systems based on SDN

Stagkopoulou, Alexandra January 2016 (has links)
Software Defined Networks (SDN) constitute the new communication paradigm ofprogrammable computer networks. By decoupling the control and date plane the networkmanagement is easier and more flexible. However, the new architecture is vulnerable to anumber of security threats, which are able to harm the network. Network monitoringsystems are pivotal in order to protect the network. To this end, the evaluation of a networkmonitoring system is crucial before the deployment of it in the real environment. Networksimulators are the complementary part of the process as they are necessary during theevaluation of the new system’s performance at the design time. This work focuses on providing a complete simulation framework which is able to(i) support SDN architectures and the OpenFlow protocol, (ii) reproduce the impact ofcyber and physical attacks against the network and (iii) provide detection and mitigationtechniques to address Denial-of-Service (DoS) attacks. The performance of the designedmonitoring system will be evaluated in terms of accuracy, reactiveness and effectiveness.The work is an extension of INET framework of OMNeT++ network simulator. / Software Defined Networks (SDN) utgör den nya kommunikationsmodellen av programmerbara datornätverk. Genom separation av kontroll- och dataplanet blir administrativ hantering av datornätverk enklare och flexiblare. Arkitekturen öppnar emellertid upp nya säkerthets hot, övervakningssystem är därför väsentliga för att skydda datornätverk. Till följd av detta är utvärdering av övervakningssystem kritiskt innan driftsättning i produktionsmiljö. Nätverkssimulatorer är den kompletterande delen i processen då de är nödvändiga för utvärdering av systemets prestanda under design fasen. Detta arbete fokuserar på att tillföra ett komplettet simulations ramverk vilket är kapabelet till; (i) ge stöd för SDN arkitekturer och OpenFlow protokollet, (ii) reproducera skadegörelsen av cyber- och fysiska attacker mot datornäterk och (iii) förse sätt att upptäcka och mildra Denial-of-Service (DoS) attacker. Prestanda av det designade övervakningssystemet är utvärderat i form av exakthet, responstid och effektivitet. Arbetet är en utvidgning av INET ramverket, som är del av OMNeT++ network simulator.
105

Development of a Low-Cost and Easy-to-Use Wearable Knee Joint Monitoring System / A Wearable Knee Joint Monitoring System

Faisal, Abu Ilius January 2020 (has links)
The loss of mobility among the elderly has become a significant health and socio-economic concern worldwide. Poor mobility due to gradual deterioration of the musculoskeletal system causes older adults to be more vulnerable to serious health risks such as joint injuries, bone fractures and traumatic brain injury. The costs associated with the treatment and management of these injuries are a huge financial/social burden on the government, society and family. Knee is one of the key joints that bear most of the body weight, so its proper function is essential for good mobility. Further, Continuous monitoring of the knee joint can potentially provide important quantitative information related to knee health and mobility that can be utilized for health assessment and early diagnoses of mobility-related problems. In this research work, we developed an easy-to-use, low-cost, multi-sensor-based wearable device to monitor and assess the knee joint and proposed an analysis system to characterize and classify an individual’s knee joint features with respect to the baseline characteristics of his/her peer group. The system is composed of a set of different miniaturized sensors (inertial motion, temperature, pressure and galvanic skin response) to obtain linear acceleration, angular velocity, skin temperature, muscle pressure and sweat rate of a knee joint during different daily activities. A database is constructed from 70 healthy adults in the age range from 18 to 86 years using the combination of all signals from our knee joint monitoring system. In order to extract relevant features from the datasets, we employed computationally efficient methods such as complementary filter and wavelet packet decomposition. Minimum redundancy maximum relevance algorithm and principal component analysis were used to select key features and reduce the dimension of the feature vectors. The obtained features were classified using the support vector machine, forming two distinct clusters in the baseline knee joint characteristics corresponding to gender, age, body mass index and knee/leg health condition. Thus, this simple, easy‐to‐use, cost-effective, non-invasive and unobtrusive knee monitoring system can be used for real-time evaluation and early diagnoses of joint disorders, fall detection, mobility monitoring and rehabilitation. / Thesis / Master of Applied Science (MASc)
106

LONG TERM VEHICLE HEALTH MONITORING

Cridland, Doug, Dehmelt, Chris 10 1900 (has links)
ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / While any vehicle that is typically part of a flight test campaign is heavily instrumented to validate its performance, long term vehicle health monitoring is performed by a significantly reduced number of sensors due to a number of issues including cost, weight and maintainability. The development and deployment of smart sensor buses has reached a time in which they can be integrated into a larger data acquisition system environment. The benefits of these types of buses include a significant reduction in the amount of wiring and overall system complexity by placing the appropriate signal conditioners close to their respective sensors and providing data back over a common bus, that also provides a single power source. The use of a smart-sensor data collection bus, such as IntelliBus™1 or IEEE-1451, along with the continued miniaturization of signal conditioning devices, leads to the interesting possibility of permanently embedding data collection capabilities within a vehicle after the initial flight test effort has completed, providing long-term health-monitoring and diagnostic functionality that is not available today. This paper will discuss the system considerations and the benefits of a smart sensor based system and how pieces can be transitioned from flight qualification to long-term vehicle health monitoring in production vehicles.
107

Egenkontroll och tillsyn : – ur de granskades perspektiv

Erikson, Daniel January 2008 (has links)
<p>Den här rapporten vill vända på perspektiven. Den beskriver inte hur samhället anser att miljölagstiftningen och miljötillsynen ska fungera. Här beskrivs istället hur företagen upplever hur den lagstadgade egenkontrollen fungerar i deras egen verksamhet och hur de upplever hur kommunens miljötillsyn fungerar. Forsk­ningen om miljötillsyn är begränsad och har hittills inte haft företagens perspek­tiv. Det är viktigt att både samhällets och företagens perspektiv lyfts fram. Bägge parter behöver arbeta på en enad front för att gemensamt kunna uppnå målet om en hållbar utveckling. Denna fallstudie, med ett begränsat antal företag i två olika kommuner, lyfter fram och bekräftar företagens syn på tillsynsmyndighetens arbete. Detta är en viktig del i dessa miljökontors kvalitetsarbete men även för framtida utveckling och användning av tillsynsmetoder. Företagen ger överlag en positiv bild om hur miljötillsynen och egenkontrollen fungerar. Egenkontrollen är ett viktigt och fungerande verktyg för de verksamheter som bedriver ett aktivt och systematiskt miljöarbete. För en mindre verksamhet kan dock system som bygger på dokumenterade rutiner kännas tungarbetat. Tillsynen upplevs ske i en givande dialog mellan myndighet och företag. Rådgivningen uppskattas och är värdefull för företagens miljöarbete. Företagarna förväntar sig däremot en mer omfattande rådgivning än vad som är myndighetens uppgift enligt lagstiftaren.</p> / <p>This report does not describe the way in which society considers how environmental legislation and environmental monitoring should work. Instead it describes the experience of a number of companies of the self monitoring system and the municipality's environmental monitoring functions. The research about environmental monitoring is limited and has not focused on the perspective of companies. It is important to elucidate the perspectives of both society and companies. Both parties work is needed in order to achieve sustainable development. The results of this case study brings out and confirms the view of a limited number of companies on the monitoring authority’s work. This is an important part in the quality work of the studied authorities, but is also necessary for future development and use of monitoring methods. The companies in the study give a positive picture about how the environment monitoring and the self monitoring system work. The self monitoring system is an important tool for a company which has an ongoing and structured environmental management system. For a smaller company systems that build on documented procedures, may however, be perceived as a burden. Another result of the study is that the companies experience the authorities´ monitoring as a rewarding dialogue between them and the authority. The advice given by the authority is appreciated and valuable for the companies' environmental work. Nevertheless, the entrepreneurs expect more extensive support than the authority can provide due to the legislation.</p>
108

Salvia suspension cultures as production systems for oleanolic and ursolic acid

Haas, Christiane, Hengelhaupt, Karl-Christoph, Kümmritz, Sibylle, Bley, Thomas, Pavlov, Atanas, Steingroewer, Juliane 26 January 2017 (has links) (PDF)
Oleanolic and ursolic acid (OA and UA) are triterpenic acids with diverse biological activities that are of interest to the pharmaceutical industry. To investigate the scope for producing these compound using cell suspension cultures of Salvia species, calli from S. officinalis, S. virgata and S. fruticosa were induced using several plant growth regulator (PGR) combinations. Eleven lines were selected for suspension induction from a pool of calli. Six suspension cultures were established successfully and cultivated in the Respiration Activity MOnitoring System® (RAMOS®) to obtain online data on their growth kinetics and to establish appropriate sampling schedules for the determination of their OA and UA production. Based on their observed growth behaviour, OA and UA contents, and aggregation properties, one suspension culture from each studied Salvia species was selected for further optimisation. The μmax values for these suspension cultures ranged from 0.20 to 0.37°d-1, their OA and UA contents were greater than 1.3 and 1.2 mg g-1, respectively, and they afforded maximum volumetric yields of 21.0 mg l-1 for OA and 32.8 mg l-1 for UA. These results will be useful in the development of a refined Salvia suspension-based process for OA and UA production.
109

Apport de la Surveillance Microsismique en Champ Proche pour la détection de Mécanismes et Signes Précurseurs aux Instabilités Gravitaires : Surveillance expérimentale d'une Cavité Saline en exploitation : Cas du site de Cerville-Buissoncourt / Contribution of Near Field Microseismic Monitoring to detect the Mechanisms and Precursor Signs of gravitational instabilities : Experimental monitoring of a salt cavern in operation : the case of Cerville-Buissoncourt site

Cao, Ngoc-Tuyen 13 December 2011 (has links)
L'étude des signes précurseurs d'un effondrement brutal au-dessus de cavités souterraines, dont le recouvrement est caractérisé par la présence d'un banc massif et raide, est un problème majeur pour la sécurité publique. Aussi, pour progresser dans la compréhension et l'évolution des mécanismes mis en jeu, une cavité saline, située dans le NE de la France, a été suivie en temps réel, entre 2004 et 2009, jusqu'à son effondrement. Celle-ci a été exploitée par dissolution, jusqu'à atteindre une dimension critique (de l'ordre de 180 m) sous un recouvrement de 180 m, armé d'un banc raide de Dolomie situé à 120 m de profondeur.Un système de mesures multi-paramètres haute résolution visait à caractériser les signes précurseurs ainsi qu'à suivre l'effondrement lui-même. Il comprenait des dispositifs à la fois géotechniques et géophysiques, dont des mesures de nivellement de surface et un réseau permanent d'écoute microsismique. Ce dernier, dont les données font l'objet principal de cette thèse, était constitué de neuf sondes équipées de géophones 40 Hz (5 unidirectionnels et 4 tridirectionnels), réparties autour et à l'aplomb de la cavité, dont une dans le banc raide.L'évolution de la cavité a été marquée par deux épisodes majeurs d'activité microsismique :- au printemps 2008, la reprise de la dissolution dans la cavité a engendré l'apparition de crises répétées avec plusieurs milliers d'événements en quelques jours, traduisant un changement de régime microsismique, marqueur de l'instabilité de la cavité ;- en février 2009, suite à ces observations, l'exploitant a décidé de provoquer l'effondrement, par le rabattement intensif de saumure dans la cavité. Pendant les trois jours d'opération, plus de 30000 événements ont été enregistrés (sur 60000 depuis 2004).L'étude de la signature des événements apporte des renseignements essentiels pour la surveillance opérationnelle et la discrimination de ces deux périodes. En particulier, alors que les valeurs maximales atteintes en amplitude, énergie au capteur et fréquence fondamentale apparente, sont assez stables au cours des crises, les sauts marqués durant l'effondrement, permettent de présumer de son imminence. L'évolution de la distribution des microséismes en termes d'énergie libérée et d'occurrence, calculée de manière similaire à la loi de Gutenberg-Richter, bien que souvent difficile à interpréter, a pu être associée à des hausses du niveau piézométrique, ainsi qu'à de petites accélérations de l'affaissement mesuré en surface. Pendant la période d'effondrement, le nombre d'événements microsismiques augmente en suivant une loi en puissance.La localisation des microséismes a nécessité la mise en place d'une stratégie adaptée pour garantir la qualité et l'homogénéité des résultats (sélection des enregistrements, calibrage, étude paramétrique).Cependant, l'utilisation d'un modèle de vitesse constant sur toute la période s'est révélé impossible, compte tenu de l'évolution rapide et permanente du milieu. Il a donc été entrepris d'établir des modèles de vitesse différents en fonction des périodes d'évolution de la cavité.Les distributions spatio-temporelles des foyers ainsi localisés montrent l'existence de structures préférentielles de rupture et souligne le rôle majeur du banc raide.Croisées avec les autres mesures acquises sur le site, ces résultats ont permis d'établir un scénario probable d'évolution de la cavité et de proposer quelques recommandations pour la surveillance opérationnelle / The study of the precursory signs of a brutal collapse above underground caverns, with an overburden characterized by the presence of a massive and stiff bench, is a major problem for public safety. Thus, to progress in the comprehension and the evolution of the concerned mechanisms, a salt cavern, located in the NE France, was monitored in real-time, since 2004 to 2009, until its collapse. This cavern was mined by solution, until reaching its critical dimension (about 180 m) under a covering of 180 m thick, armed with a stiff Dolomite bench located at 120 m of depth.A multi-parameter high resolution monitoring system aimed at characterizing the precursory signs and following collapse itself. It included both geotechnical and geophysical devices as surface leveling measurements and a permanent microseismic network. This one, which data are the principal subject of this thesis, consisted in nine probes equipped with 40 Hz geophones (5 1D and 4 3D), distributed around and directly below the cavern, including one located in the stiff bench.The evolution of the cavern was marked by two major episodes of microseismic activity:- at the beginning of spring 2008, the dissolution restart in the cavern which caused repeated crisis with several thousand events in a few days, this represent a change in the microseismic regime and marked the cavern instability;- in February 2009, following these observations, the owner decided to trigger the collapse by intensive brine pumping in the cavern. During the three days of the operation, more than 30,000 events were recorded (against 60,000 since 2004).The study of the event signature provides essential information for operational monitoring and the discrimination of these two periods. Particularly, while maximal values reached in amplitude, energy and apparent fundamental frequency are quite stable during the 2008 episodes, the rises of this values are important during the collapse period (prior to the peak of activity), allowed us to suppose its imminence. The evolution of the microseism distribution in terms of energy released and occurrence, calculated similarly to the Gutenberg-Richter law, although often difficult to interpret, has been associated with piezometric level rises, and with small accelerations of surface subsidence. During the collapse, the microseismic activity acceleration follows a power law.Microseisms location required the establishment of an appropriate strategy to ensure the quality and the consistency of the results (record selection, calibration, parametric analysis). However, the use of a constant velocity model over all the period was impossible due to the fast and permanent evolution of the environment. Thus, several models were used, according to the a priori known cavern evolution.The event spatiotemporal distributions, thus located, revealed the existence of preferential failure structures and highlight the role of the stiff bench, located at 120 m depth
110

An FPGA Based MPPT and Monitoring System : suitable for a photovoltaic based microgrid

Zheng, Rongpeng January 2019 (has links)
Microgrids containing photovoltaic (PV) cells and wind power gain more and more interest. These microgrids may work in stand-alone mode ("islanding") or be conncted to the main grid. In both modes of operation, power quality must be monitored and controlled. This report focuses on microgrids and aims to implement a monitoring system based on FPGA. In the monitoring system, two applications can be achieved, firstly a PAS-MPPT algorithm in a DC-DC boost converter to improve the maximun power point tracking of a PV unit, and secondly a detection and switching system of the grid mode - stand-alone or connected to the main grid. Simulation results prove the Verilog programs in FPGA are suitable to be used in microgrids.

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