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De, Marco Luisa <1984>. "Optical Design for Automatic Identification and Portable Systems." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amsdottorato.unibo.it/4600/1/DeMarco_Luisa_Tesi.pdf.
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This thesis proposes design methods and test tools, for optical systems, which may be used in an industrial environment, where not only precision and reliability but also ease of use is important. The approach to the problem has been conceived to be as general as possible, although in the present work, the design of a portable device for automatic identification applications has been studied, because this doctorate has been funded by Datalogic Scanning Group s.r.l., a world-class producer of barcode readers.
The main functional components of the complete device are: electro-optical imaging, illumination and pattern generator systems.
For what concerns the electro-optical imaging system, a characterization tool and an analysis one has been developed to check if the desired performance of the system has been achieved. Moreover, two design tools for optimizing the imaging system have been implemented. The first optimizes just the core of the system, the optical part, improving its performance ignoring all other contributions and generating a good starting point for the optimization of the whole complex system. The second tool optimizes the system taking into account its behavior with a model as near as possible to reality including optics, electronics and detection.
For what concerns the illumination and the pattern generator systems, two tools have been implemented. The first allows the design of free-form lenses described by an arbitrary analytical function exited by an incoherent source and is able to provide custom illumination conditions for all kind of applications. The second tool consists of a new method to design Diffractive Optical Elements excited by a coherent source for large pattern angles using the Iterative Fourier Transform Algorithm.
Validation of the design tools has been obtained, whenever possible, comparing the performance of the designed systems with those of fabricated prototypes. In other cases simulations have been used.
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De, Marco Luisa <1984>. "Optical Design for Automatic Identification and Portable Systems." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amsdottorato.unibo.it/4600/.
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This thesis proposes design methods and test tools, for optical systems, which may be used in an industrial environment, where not only precision and reliability but also ease of use is important. The approach to the problem has been conceived to be as general as possible, although in the present work, the design of a portable device for automatic identification applications has been studied, because this doctorate has been funded by Datalogic Scanning Group s.r.l., a world-class producer of barcode readers.
The main functional components of the complete device are: electro-optical imaging, illumination and pattern generator systems.
For what concerns the electro-optical imaging system, a characterization tool and an analysis one has been developed to check if the desired performance of the system has been achieved. Moreover, two design tools for optimizing the imaging system have been implemented. The first optimizes just the core of the system, the optical part, improving its performance ignoring all other contributions and generating a good starting point for the optimization of the whole complex system. The second tool optimizes the system taking into account its behavior with a model as near as possible to reality including optics, electronics and detection.
For what concerns the illumination and the pattern generator systems, two tools have been implemented. The first allows the design of free-form lenses described by an arbitrary analytical function exited by an incoherent source and is able to provide custom illumination conditions for all kind of applications. The second tool consists of a new method to design Diffractive Optical Elements excited by a coherent source for large pattern angles using the Iterative Fourier Transform Algorithm.
Validation of the design tools has been obtained, whenever possible, comparing the performance of the designed systems with those of fabricated prototypes. In other cases simulations have been used.
3
Kim, Jijoong. "Automatic aircraft recognition and identification." Access electronically, 2005. http://www.library.uow.edu.au/adt-NWU/public/adt-NWU20060808.161115/index.html.
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Cabell, Randolph H. "The automatic identification of aerospace acoustic sources." Thesis, Virginia Tech, 1989. http://hdl.handle.net/10919/45932.
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<p>This work describes the design of an intelligent recognition system used to distinguish noise
signatures of five different acoustic sources. The system uses pattern recognition techniques to
identify the information obtained from a single microphone. A training phase is used in which the
system learns to distinguish the sources and automatically selects features for optimal performance.
Results were obtained by training the system to distinguish jet planes, propeller planes, a helicopter,
train, and wind turbine from one another, then presenting similar sources to the system and
recording the number of errors. These results indicate the system can successfully identify the
trained sources based on acoustic information. Classification errors highlight the impact of the
training sources on the system's ability to recognize different sources.
</p><br>Master of Science
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Hidayat, Egi. "On Identification of Biological Systems." Doctoral thesis, Uppsala universitet, Avdelningen för systemteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-215699.
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System identification finds nowadays application in various areas of biological research as a tool of empiric mathematical modeling and model individualization. A fundamental challenge of system identification in biology awaits in the form of response variability. Furthermore, biological systems tend to exhibit high degree of nonlinearity as well as significant time delays. This thesis covers system identification approaches developed for the applications within two particular biomedical fields: neuroscience and endocrinology. The first topic of the thesis is parameter estimation of the classical Elementary Motion Detector (EMD) model in insect vision. There are two important aspects to be taken care of in the identification approach, namely the nonlinear dynamics of the individual EMD and the spatially distributed structure of multiple detectors producing a measurable neural response. Hence, the suggested identification method is comprised of two consecutive stages addressing each of the above aspects. Furthermore, visual stimulus design for high spatial excitation order has been investigated. The second topic is parameter estimation of mathematical model for testosterone regulation in the human male. The main challenges of this application are in the unavailability of input signal measurements and the presence of an unknown pulsatile feedback in the system resulting in a highly nonlinear closed-loop dynamics. Semi-blind identification method has been developed based on a recently proposed pulse-modulated model of pulsatile endocrine regulation. The two system identification problems treated in the thesis bear some resemblance in the sense that both involve measured signals that can be seen as square-integrable functions of time. This property is handled by transforming the signals into the Laguerre domain, i.e. by equivalently representing the functions with their infinite Laguerre series.
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Qin, Tiantian. "Identification of Reliable Cues for an Automatic Deception Detection System." Diss., The University of Arizona, 2007. http://hdl.handle.net/10150/194385.
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An automatic deception detection system (ADDS) is to detect deceptive human behavior with machine extractable evidences (i.e., cues). One of the most prominent challenges for building a ADDS is the availability of reliable cues. This study represents one of the first attempts to address the system's reliability by identifying the set of reliable cues in order to improve the system performance (detection accuracy).This study addresses two critical challenges of existing machine cues, irreproducibility and inconsistency. First, in order to mitigate the irreproducibility, the study introduces a set of machine measurable cues to estimate the commonality of related machine cues. These more reproducible cues are referred to as the macro cues which can be applied for automatic pattern recognition. Second, in order to address the consistency, the study separates cues based on the controllability, and defines the strategic cues as those can easily be manipulated by deceivers during interaction. The strategic cues fluctuate during deception and thus are less consistently reliable as predictors for the ADDS. On the contrary, the nonstrategic cues are more consistent. This study also considers other moderator effects that influencing the ADDS performance: time and the condition of interviewer's immediacy (ERIMD).The macro cues are automatically estimated from the micro cues based on the predefined relational models. The empirical data support the relationship models between macro and micro cues. Results show that macro cues mitigate the irreproducibility problem by reducing the variability in the single cues. However, the results also show that using macro cues as predictors in the discriminant analysis does not perform better than micro cues, and thus imply the needs to adjust weights of important components when constructing the macro cues. In terms of the consistent cues, results show that the nonstrategic cues are relatively more consistent than strategic ones in ADDS performance. Furthermore, the study suggests that particular detection methods must be tailored according to the feature of strategic and nonstrategic cues. The findings have many potential implications. One is to use the macro cues to recognize the dynamic patterns in deceptive behaviors. Specifically, truthtellers increase the certainty, immediacy, and tend to decrease the cognitive load; but deceivers behave the opposite. The other is to rely on the characteristics of strategic cues to manipulate the communication environment to improve the ADDS performance. This concept is also referred to as the Proactive Deception Detection (PDD). In the current study, the interviewer's immediacy is a controllable environment factor for PDD. The high ERIMD increase the system performance because it has higher overhead added to the deceptive behavior to trigger more abnormal cues. In sum, methods and results of this study have multiple impacts in information assurance and human-computer interaction.
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Combrinck, Hendrik Petrus. "A cost, complexity and performance comparison of two automatic language identification architectures." Pretoria : [s.n.], 2006. http://upetd.up.ac.za/thesis/available/etd-12212006-141335/.
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Kuriakose, Rengith Baby. "Automatic student attendance registration using radio frequency identification (RFID)." Thesis, [Bloemfontein?] : Central University of Technology, Free State, 2010. http://hdl.handle.net/11462/27.
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Thesis (M. Tech.) - Central University of Technology, Free State, 2010<br>The main aim of this research was to automate student attendance registration, thereby reducing human involvement in the whole process. This was made possible using Radio Frequency Identification (RFID) technology.
The Central University of Technology uses student cards that are compatible for use with RFID technology. As a result, no initial investment (except for the existing personal computer’s and the constructed RFID reader) in infrastructure was required for this project.
The basic working of the project was as follows. The students belonging to a specific class had their vital educational data (Student number, Name) entered into a database table at the time of registration. A student card containing a serial number, with reference to the data contained in the database table, was given to the students after registration.
The students walk into their respective classes and scan their student cards with the RFID reader. The serial number stored in the student card is transferred to the reader and from there wirelessly to the main server using ZigBee technology. In the main server, using Java programming language, the card serial number is sent to the Integrated Development Environment (IDE). In this project the Netbeans IDE (Java platform) was used.
The Netbeans IDE is connected to the Apache Derby database using Java Database Connector (JDBC), so the serial number (which is referenced to the educational data of the students) from the student card is automatically compared with the original database created at the time of registration. Once a match is confirmed between the two entries, the data is entered into a separate database table which serves as the basic attendance sheet for a specific day.
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Byrne, Carlton B. "Assembly task identification and strategy development using expert systems and neural networks." Thesis, Cardiff University, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266650.
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Bhattacharjee, Partha Sarathi S. M. Massachusetts Institute of Technology. "VacSeen : semantically enriched automatic identification and data capture for improved vaccine logistics." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/107582.
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Thesis: S.M. in Technology and Policy, Massachusetts Institute of Technology, School of Engineering, Institute for Data, Systems, and Society, Technology and Policy Program, 2016.<br>Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, School of Engineering, Institute for Data, Systems, and Society, System Design and Management Program, 2016.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references (pages 79-82).<br>Vaccines are globally recognized as a critical public health intervention. Routine immunization coverage in large parts of the developing world is around 80%. Technology and policy initiatives are presently underway to improve vaccine access in such countries. Efforts to deploy AIDC technologies, such as barcodes, on vaccine packaging in developing countries are currently ongoing under the aegis of the 'Decade of Vaccines' initiative by key stakeholders. Such a scenario presents an opportunity to evaluate novel approaches for enhancing vaccine access. In this thesis I report the development of VacSeen, a Semantic Web technology-enabled platform for improving vaccine access in developing countries. Furthermore, I report results of evaluation of a suite of constituent software and hardware tools pertaining to facilitating equitable vaccine access in resource-constrained settings through data linkage and temperature sensing. I subsequently discuss the value of such linkage and approaches to implementation using concepts from technology, policy, and systems analysis.<br>by Partha Sarathi Bhattacharjee.<br>S.M. in Technology and Policy<br>S.M. in Engineering and Management
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Chandu, Kartheek. "Automatic image registration and defect identification of a class of structural artifacts in printed documents /." Online version of thesis, 2008. http://hdl.handle.net/1850/7761.
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Gillberg, Jonas. "Frequency Domain Identification of Continuous-Time Systems : Reconstruction and Robustness." Doctoral thesis, Linköping : Department of Electrical Engineering, Linköpings universitet, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-7483.
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Reynolds, Douglas A. "A Gaussian mixture modeling approach to text-independent speaker identification." Diss., Georgia Institute of Technology, 1992. http://hdl.handle.net/1853/16903.
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Lee, Jong Yeol. "Integrating spatial and spectral information for automatic feature identification in high resolution remotely sensed images." Morgantown, W. Va. : [West Virginia University Libraries], 2000. http://etd.wvu.edu/templates/showETD.cfm?recnum=1600.
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Thesis (Ph. D.)--West Virginia University, 2000.<br>Title from document title page. Document formatted into pages; contains x, 132 p. : ill. (some col.), maps (some col.). Includes abstract. Includes bibliographical references (p. 124-132).
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Gerdin, Markus. "Identification and Estimation for Models Described by Differential-Algebraic Equations." Doctoral thesis, Linköping : Department of Electrical Engineering, Linköpings universitet, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-7600.
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Soderstrom, Tyler Andrew. "Integration of on-line data reconciliation and bias identification techniques /." Full text (PDF) from UMI/Dissertation Abstracts International, 2001. http://wwwlib.umi.com/cr/utexas/fullcit?p3008445.
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Kaminskyj, Ian. "Automatic recognition of musical instruments using isolated monophonic sounds." Monash University, Dept. of Electrical and Computer Systems Engineering, 2004. http://arrow.monash.edu.au/hdl/1959.1/5212.
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Dufourd, Claire Chantal. "Spatio-temporal mathematical models of insect trapping : analysis, parameter estimation and applications to control." Thesis, University of Pretoria, 2016. http://hdl.handle.net/2263/58471.
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This thesis provides a mathematical framework for the development of efficient control strategies that satisfy the charters of Integrated Pest Management (IPM) which aims to maintain pest population at a low impact level. This mathematical framework is based on a dynamical system approach and comprises the construction of mathematical models, their theoretical study, the development of adequate schemes for numerical solutions and reliable procedures for parameter identification. The first output of this thesis is the construction of trap-insect spatio-temporal models formulated via advection-diffusion-reaction processes. These models were used to simulate numerically trapping to compare with field data. As a result, practical protocols were identified to estimate pest-population size and distribution as well as its dispersal capacity and parameter values related to the attractiveness of the traps. The second major output of this thesis is the prediction of the impact of a specific control method: mating disruption using a female pheromone and trapping. A compartmental model, formulated via a system of ordinary differential equations, was built based on biological and mating behaviour knowledge of the pest. The theoretical analysis of the model yields threshold values for the dosage of the pheromone above which extinction of the population is ensured. The practical relevance of the results obtained in this thesis shows that mathematical modelling is an essential supplement to experiments in optimizing control strategies.<br>Thesis (PhD)--University of Pretoria, 2016.<br>Mathematics and Applied Mathematics<br>PhD<br>Unrestricted
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Maree, Johannes Philippus. "Fault detection for the Benfield process using a closed-loop subspace re-identification approach." Pretoria : [s.n.], 2009. http://upetd.up.ac.za/thesis/available/etd-11262009-224053/.
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Thesis (M.Eng.(Faculty of Engineering, The Built Environment and Information Technology))--University of Pretoria, 2009.<br>Abstracts in English and Afrikaans. Includes bibliographical references (leaves 180-187).
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Tootell, Holly. "The social impact of using automatic identification technologies and location-based services in national security." Access electronically, 2007. http://www.library.uow.edu.au/adt-NWU/public/adt-NWU20080519.145309/index.html.
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Sanderson, Conrad, and conradsand@ieee org. "Automatic Person Verification Using Speech and Face Information." Griffith University. School of Microelectronic Engineering, 2003. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20030422.105519.
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Identity verification systems are an important part of our every day life. A typical example is the Automatic Teller Machine (ATM) which employs a simple identity verification scheme: the user is asked to enter their secret password after inserting their ATM card; if the password matches the one prescribed to the card, the user is allowed access to their bank account. This scheme suffers from a major drawback: only the validity of the combination of a certain possession (the ATM card) and certain knowledge (the password) is verified. The ATM card can be lost or stolen, and the password can be compromised. Thus new verification methods have emerged, where the password has either been replaced by, or used in addition to, biometrics such as the persons speech, face image or fingerprints. Apart from the ATM example described above, biometrics can be applied to other areas, such as telephone & internet based banking, airline reservations & check-in, as well as forensic work and law enforcement applications. Biometric systems based on face images and/or speech signals have been shown to be quite effective. However, their performance easily degrades in the presence of a mismatch between training and testing conditions. For speech based systems this is usually in the form of channel distortion and/or ambient noise; for face based systems it can be in the form of a change in the illumination direction. A system which uses more than one biometric at the same time is known as a multi-modal verification system; it is often comprised of several modality experts and a decision stage. Since a multi-modal system uses complimentary discriminative information, lower error rates can be achieved; moreover, such a system can also be more robust, since the contribution of the modality affected by environmental conditions can be decreased. This thesis makes several contributions aimed at increasing the robustness of single- and multi-modal verification systems. Some of the major contributions are listed below. The robustness of a speech based system to ambient noise is increased by using Maximum Auto-Correlation Value (MACV) features, which utilize information from the source part of the speech signal. A new facial feature extraction technique is proposed (termed DCT-mod2), which utilizes polynomial coefficients derived from 2D Discrete Cosine Transform (DCT) coefficients of spatially neighbouring blocks. The DCT-mod2 features are shown to be robust to an illumination direction change as well as being over 80 times quicker to compute than 2D Gabor wavelet derived features. The fragility of Principal Component Analysis (PCA) derived features to an illumination direction change is solved by introducing a pre-processing step utilizing the DCT-mod2 feature extraction. We show that the enhanced PCA technique retains all the positive aspects of traditional PCA (that is, robustness to compression artefacts and white Gaussian noise) while also being robust to the illumination direction change. Several new methods, for use in fusion of speech and face information under noisy conditions, are proposed; these include a weight adjustment procedure, which explicitly measures the quality of the speech signal, and a decision stage comprised of a structurally noise resistant piece-wise linear classifier, which attempts to minimize the effects of noisy conditions via structural constraints on the decision boundary.
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Lareau, Jonathan. "Application of shifted delta cepstral features for GMM language identification /." Electronic version of thesis, 2006. https://ritdml.rit.edu/dspace/handle/1850/2686.
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Chan, Siu Man. "Improved speaker verification with discrimination power weighting /." View abstract or full-text, 2004. http://library.ust.hk/cgi/db/thesis.pl?ELEC%202004%20CHANS.
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Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2004.<br>Includes bibliographical references (leaves 86-93). Also available in electronic version. Access restricted to campus users.
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Kilic, Ergin. "Structured Neural Networks For Modeling And Identification Of Nonlinear Mechanical Systems." Phd thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614735/index.pdf.
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Most engineering systems are highly nonlinear in nature and thus one could not
develop efficient mathematical models for these systems. Artificial neural
networks, which are used in estimation, filtering, identification and control in
technical literature, are considered as universal modeling and functional
approximation tools. Unfortunately, developing a well trained monolithic type
neural network (with many free parameters/weights) is known to be a daunting
task since the process of loading a specific pattern (functional relationship) onto a
generic neural network is proven to be a NP-complete problem. It implies that if
training is conducted on a deterministic computer, the time required for training
process grows exponentially with increasing size of the free parameter space (and
the training data in correlation). As an alternative modeling technique for
nonlinear dynamic systems<br>this thesis proposed a general methodology for
structured neural network topologies and their corresponding applications are
realized. The main idea behind this (rather classic) divide-and-conquer approach is to employ a priori information on the process to divide the problem into its
fundamental components. Hence, a number of smaller neural networks could be
designed to tackle with these elementary mapping problems. Then, all these
networks are combined to yield a tailored structured neural network for the
purpose of modeling the dynamic system under study accurately. Finally,
implementations of the devised networks are taken into consideration and the
efficiency of the proposed methodology is tested on four different types of
mechanical systems.
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Wark, Timothy J. "Multi-modal speech processing for automatic speaker recognition." Thesis, Queensland University of Technology, 2001.
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Enqvist, Martin. "Linear Models of Nonlinear Systems." Doctoral thesis, Linköping : Linköpings universitet, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-5330.
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Kavirayani, Srikanth. "Classical and neural net control and identification of non-linear systems with application to the two-joint inverted pendulum control problem." Diss., Columbia, Mo. : University of Missouri-Columbia, 2005. http://hdl.handle.net/10355/5835.
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Thesis (M.S.)--University of Missouri-Columbia, 2005.<br>The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (January 23, 2007) Includes bibliographical references.
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Petersson, Martin. "Impact evaluation of an automatic identificationtechnology on inventory management : A simulation approach with the focus on RFID." Thesis, Mittuniversitetet, Institutionen för informationssystem och –teknologi, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-41387.
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Automatic identification system is a prominent technology used in warehouses to give managers real time information of their products and assistance to warehouse employees in keeping an accurate inventory record. This kind of assistance is needed as an inaccurate inventory leads to profit loss due to misplacement or other mistakes. This project cooperated with an organization called Stora Enso specifically one of their forest nursery to find a solution to improve their inventory management system. Their current inventory system is a manual process which leads to mistakes occurring that affects the inventory accuracy. This thesis project evaluates automatic identification systems to observe if the technology is a possible solution and aims to answer the research question ”What are the significant impacts an automatic identification system has on an inventory management system?”. From the automatic identification evaluation one system is picked for further evaluation and due to its advantages radio frequency identification (RFID) is picked. To evaluate RFID in a warehouse setting a discrete-event simulation was created that simulates the forest nursery’s warehouse. The simulation is then used to evaluate the impact of different RFID implementations and their respective cost. The simulation results show that just a simple RFID implementation can improve inventory accuracy and remove some of the mistakes a manual system has with a relatively low direct cost. It also shows that a full RFID implementation that gives full visibility of a warehouse can almost remove inventory mistakes however the cost analysis shows that it requires a large investment.
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Souza, Vinicius Mourão Alves de. "Classificação de fluxo de dados não estacionários com aplicação em sensores identificadores de insetos." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/55/55134/tde-13122016-113648/.
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Diversas aplicações são responsáveis por gerar dados ao longo do tempo de maneira contínua, ordenada e ininterrupta em um ambiente dinâmico, denominados fluxo de dados. Entre possíveis tarefas que podem ser realizadas com estes dados, classificação é uma das mais proeminentes. Devido à natureza não estacionária do ambiente responsável por gerar os dados, as características que descrevem os conceitos das classes do problema de classificação podem se alterar ao longo do tempo. Por isso, classificadores de fluxo de dados requerem constantes atualizações em seus modelos para que a taxa de acerto se mantenha estável ao longo do tempo. Na etapa de atualização a maior parte das abordagens considera que, após a predição de cada exemplo, o seu rótulo correto é imediatamente disponibilizado sem qualquer atraso de tempo (latência nula). Devido aos altos custos do processo de rotulação, os rótulos corretos nem sempre podem ser obtidos para a maior parte dos dados ou são obtidos após um considerável atraso de tempo. No caso mais desafiador, encontram-se as aplicações em que após a etapa de classificação dos exemplos, os seus respectivos rótulos corretos nunca sã disponibilizados para o algoritmo, caso chamado de latência extrema. Neste cenário, não é possível o uso de abordagens tradicionais, sendo necessário o desenvolvimento de novos métodos que sejam capazes de manter um modelo de classificação atualizado mesmo na ausência de dados rotulados. Nesta tese, além de discutir o problema de latência na tarefa de classificação de fluxo de dados não estacionários, negligenciado por boa parte da literatura, também sã propostos dois algoritmos denominados SCARGC e MClassification para o cenário de latência extrema. Ambas as propostas se baseiam no uso de técnicas de agrupamento para a adaptação à mudanças de maneira não supervisionada. Os algoritmos propostos são intuitivos, simples e apresentam resultados superiores ou equivalentes a outros algoritmos da literatura em avaliações com dados sintéticos e reais, tanto em termos de acurácia de classificação como em tempo computacional. Aléem de buscar o avanço no estado-da-arte na área de aprendizado em fluxo de dados, este trabalho também apresenta contribuições para uma importante aplicação tecnológica com impacto social e na saúde pública. Especificamente, explorou-se um sensor óptico para a identificação automática de espécies de insetos a partir da análise de informações provenientes do batimento de asas dos insetos. Para a descrição dos dados, foi verificado que os coeficientes Mel-cepstrais apresentaram os melhores resultados entre as diferentes técnicas de processamento digital de sinais avaliadas. Este sensor é um exemplo concreto de aplicação responsável por gerar um fluxo de dados em que é necessário realizar classificações em tempo real. Durante a etapa de classificação, este sensor exige a adaptação a possíveis variações em condições ambientais, responsáveis por alterar o comportamento dos insetos ao longo do tempo. Para lidar com este problema, é proposto um Sistema com Múltiplos Classificadores que realiza a seleção dinâmica do classificador mais adequado de acordo com características de cada exemplo de teste. Em avaliações com mudanças pouco significativas nas condições ambientais, foi possível obter uma acurácia de classificação próxima de 90%, no cenário com múltiplas classes e, cerca de 95% para a identificação da espécie Aedes aegypti, considerando o treinamento com uma única classe. No cenário com mudanças significativas nos dados, foi possível obter 91% de acurácia em um problema com 5 classes e 96% para a classificação de insetos vetores de importantes doenças como dengue e zika vírus.<br>Many applications are able to generate data continuously over t ime in an ordered and uninterrupted way in a dynamic environment , called data streams. Among possible tasks that can be performed with these data, classification is one of the most prominent . Due to non-stationarity of the environment that generates the data, the features that describe the concepts of the classes can change over time. Thus, the classifiers that deal with data streams require constants updates in their classification models to maintain a stable accuracy over time. In the update phase, most of the approaches assume that after the classification of each example from the stream, their actual class label is available without any t ime delay (zero latency). Given the high label costs, it is more reasonable to consider that this delay could vary for the most portion of the data. In the more challenging case, there are applications with extreme latency, where in after the classification of the examples, heir actual class labels are never available to the algorithm. In this scenario, it is not possible to use traditional approaches. Thus, there is the need of new methods that are able to maintain a classification model updated in the absence of labeled data. In this thesis, besides to discuss the problem of latency to obtain actual labels in data stream classification problems, neglected by most of the works, we also propose two new algorithms to deal with extreme latency, called SCARGC and MClassification. Both algorithms are based on the use of clustering approaches to adapt to changes in an unsupervised way. The proposed algorithms are intuitive, simpleand showed superior or equivalent results in terms of accuracy and computation time compared to other approaches from literature in an evaluation on synthetic and real data. In addition to the advance in the state-of-the-art in the stream learning area, this thesis also presents contributions to an important technological application with social and public health impacts. Specifically, it was studied an optical sensor to automatically identify insect species by the means of the analysis of information coming from wing beat of insects. To describe the data, we conclude that the Mel-cepst ral coefficients guide to the best results among different evaluated digital signal processing techniques. This sensor is a concrete example of an applicat ion that generates a data st ream for which it is necessary to perform real-time classification. During the classification phase, this sensor must adapt their classification model to possible variat ions in environmental conditions, responsible for changing the behavior of insects. To address this problem, we propose a System with Multiple Classifiers that dynamically selects the most adequate classifier according to characteristics of each test example. In evaluations with minor changes in the environmental conditions, we achieved a classification accuracy close to 90% in a scenario with multiple classes and 95% when identifying Aedes aegypti species considering the training phase with only the positive class. In the scenario with considerable changes in the environmental conditions, we achieved 91% of accuracy considering 5 species and 96% to classify vector mosquitoes of important diseases as dengue and zika virus.
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Lind, Ingela. "Regressor and Structure Selection : Uses of ANOVA in System Identification." Doctoral thesis, Linköping : Linköpings universitet, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-7000.
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Nkadimeng, Calvin. "Language identification using Gaussian mixture models." Thesis, Stellenbosch : University of Stellenbosch, 2010. http://hdl.handle.net/10019.1/4170.
Full textAbstract:
Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2010.<br>ENGLISH ABSTRACT: The importance of Language Identification for African languages is seeing a
dramatic increase due to the development of telecommunication infrastructure
and, as a result, an increase in volumes of data and speech traffic in public
networks. By automatically processing the raw speech data the vital assistance
given to people in distress can be speeded up, by referring their calls to a person
knowledgeable in that language.
To this effect a speech corpus was developed and various algorithms were implemented
and tested on raw telephone speech data. These algorithms entailed
data preparation, signal processing, and statistical analysis aimed at discriminating
between languages. The statistical model of Gaussian Mixture Models
(GMMs) were chosen for this research due to their ability to represent an entire
language with a single stochastic model that does not require phonetic transcription.
Language Identification for African languages using GMMs is feasible, although
there are some few challenges like proper classification and accurate
study into the relationship of langauges that need to be overcome. Other methods
that make use of phonetically transcribed data need to be explored and
tested with the new corpus for the research to be more rigorous.<br>AFRIKAANSE OPSOMMING: Die belang van die Taal identifiseer vir Afrika-tale is sien ’n dramatiese toename
te danke aan die ontwikkeling van telekommunikasie-infrastruktuur en as gevolg
’n toename in volumes van data en spraak verkeer in die openbaar netwerke.Deur
outomaties verwerking van die ruwe toespraak gegee die noodsaaklike hulp verleen
aan mense in nood kan word vinniger-up ”, deur te verwys hul oproepe na
’n persoon ingelichte in daardie taal.
Tot hierdie effek van ’n toespraak corpus het ontwikkel en die verskillende algoritmes
is gemplementeer en getoets op die ruwe telefoon toespraak gegee.Hierdie
algoritmes behels die data voorbereiding, seinverwerking, en statistiese analise
wat gerig is op onderskei tussen tale.Die statistiese model van Gauss Mengsel
Modelle (GGM) was gekies is vir hierdie navorsing as gevolg van hul vermo
te verteenwoordig ’n hele taal met’ n enkele stogastiese model wat nodig nie
fonetiese tanscription nie.
Taal identifiseer vir die Afrikatale gebruik GGM haalbaar is, alhoewel daar
enkele paar uitdagings soos behoorlike klassifikasie en akkurate ondersoek na die
verhouding van TALE wat moet oorkom moet word.Ander metodes wat gebruik
maak van foneties getranskribeerde data nodig om ondersoek te word en getoets
word met die nuwe corpus vir die ondersoek te word strenger.
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Rensfelt, Agnes. "Viscoelastic Materials : Identification and Experiment Design." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-111283.
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Wernholt, Erik. "Multivariable Frequency-Domain Identification of Industrial Robots." Doctoral thesis, Linköping : Department of Electrical Engineering, Linköping University, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-10149.
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Sanderson, Conrad. "Automatic Person Verification Using Speech and Face Information." Thesis, Griffith University, 2003. http://hdl.handle.net/10072/367191.
Full textAbstract:
Identity verification systems are an important part of our every day life. A typical example is the Automatic Teller Machine (ATM) which employs a simple identity verification scheme: the user is asked to enter their secret password after inserting their ATM card; if the password matches the one prescribed to the card, the user is allowed access to their bank account. This scheme suffers from a major drawback: only the validity of the combination of a certain possession (the ATM card) and certain knowledge (the password) is verified. The ATM card can be lost or stolen, and the password can be compromised. Thus new verification methods have emerged, where the password has either been replaced by, or used in addition to, biometrics such as the person’s speech, face image or fingerprints. Apart from the ATM example described above, biometrics can be applied to other areas, such as telephone & internet based banking, airline reservations & check-in, as well as forensic work and law enforcement applications. Biometric systems based on face images and/or speech signals have been shown to be quite effective. However, their performance easily degrades in the presence of a mismatch between training and testing conditions. For speech based systems this is usually in the form of channel distortion and/or ambient noise; for face based systems it can be in the form of a change in the illumination direction. A system which uses more than one biometric at the same time is known as a multi-modal verification system; it is often comprised of several modality experts and a decision stage. Since a multi-modal system uses complimentary discriminative information, lower error rates can be achieved; moreover, such a system can also be more robust, since the contribution of the modality affected by environmental conditions can be decreased. This thesis makes several contributions aimed at increasing the robustness of single- and multi-modal verification systems. Some of the major contributions are listed below. The robustness of a speech based system to ambient noise is increased by using Maximum Auto-Correlation Value (MACV) features, which utilize information from the source part of the speech signal. A new facial feature extraction technique is proposed (termed DCT-mod2), which utilizes polynomial coefficients derived from 2D Discrete Cosine Transform (DCT) coefficients of spatially neighbouring blocks. The DCT-mod2 features are shown to be robust to an illumination direction change as well as being over 80 times quicker to compute than 2D Gabor wavelet derived features. The fragility of Principal Component Analysis (PCA) derived features to an illumination direction change is solved by introducing a pre-processing step utilizing the DCT-mod2 feature extraction. We show that the enhanced PCA technique retains all the positive aspects of traditional PCA (that is, robustness to compression artefacts and white Gaussian noise) while also being robust to the illumination direction change. Several new methods, for use in fusion of speech and face information under noisy conditions, are proposed; these include a weight adjustment procedure, which explicitly measures the quality of the speech signal, and a decision stage comprised of a structurally noise resistant piece-wise linear classifier, which attempts to minimize the effects of noisy conditions via structural constraints on the decision boundary.<br>Thesis (PhD Doctorate)<br>Doctor of Philosophy (PhD)<br>School of Microelectronic Engineering<br>Full Text
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Brus, Linda. "Nonlinear Identification and Control with Solar Energy Applications." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-8594.
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Schön, Thomas B. "Estimation of Nonlinear Dynamic Systems : Theory and Applications." Doctoral thesis, Linköpings universitet, Reglerteknik, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-7124.
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This thesis deals with estimation of states and parameters in nonlinear and non-Gaussian dynamic systems. Sequential Monte Carlo methods are mainly used to this end. These methods rely on models of the underlying system, motivating some developments of the model concept. One of the main reasons for the interest in nonlinear estimation is that problems of this kind arise naturally in many important applications. Several applications of nonlinear estimation are studied. The models most commonly used for estimation are based on stochastic difference equations, referred to as state-space models. This thesis is mainly concerned with models of this kind. However, there will be a brief digression from this, in the treatment of the mathematically more intricate differential-algebraic equations. Here, the purpose is to write these equations in a form suitable for statistical signal processing. The nonlinear state estimation problem is addressed using sequential Monte Carlo methods, commonly referred to as particle methods. When there is a linear sub-structure inherent in the underlying model, this can be exploited by the powerful combination of the particle filter and the Kalman filter, presented by the marginalized particle filter. This algorithm is also known as the Rao-Blackwellized particle filter and it is thoroughly derived and explained in conjunction with a rather general class of mixed linear/nonlinear state-space models. Models of this type are often used in studying positioning and target tracking applications. This is illustrated using several examples from the automotive and the aircraft industry. Furthermore, the computational complexity of the marginalized particle filter is analyzed. The parameter estimation problem is addressed for a relatively general class of mixed linear/nonlinear state-space models. The expectation maximization algorithm is used to calculate parameter estimates from batch data. In devising this algorithm, the need to solve a nonlinear smoothing problem arises, which is handled using a particle smoother. The use of the marginalized particle filter for recursive parameterestimation is also investigated. The applications considered are the camera positioning problem arising from augmented reality and sensor fusion problems originating from automotive active safety systems. The use of vision measurements in the estimation problem is central to both applications. In augmented reality, the estimates of the camera’s position and orientation are imperative in the process of overlaying computer generated objects onto the live video stream. The objective in the sensor fusion problems arising in automotive safety systems is to provide information about the host vehicle and its surroundings, such as the position of other vehicles and the road geometry. Information of this kind is crucial for many systems, such as adaptive cruise control, collision avoidance and lane guidance.
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Arikan, Kutluk Bilge. "Identification Of Handling Models For Road Vehicles." Phd thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/12609440/index.pdf.
Full textAbstract:
This thesis reports the identification of linear and nonlinear handling models for road vehicles starting from structural identifiability analysis, continuing with the experiments to acquire data on a vehicle equipped with a sensor set and data acquisition system and ending with the estimation of parameters using the collected data. The 2 degrees of
freedom (dof) linear model structure originates from the well known linear bicycle model that is frequently used in handling analysis of road vehicles. Physical parameters of the bicycle model structure are selected as the unknown parameter set that is to be identified. Global identifiability of the model structure is analysed, in detail, and concluded according to various available sensor sets. Physical parameters of the bicycle model structure are estimated using prediction error estimation method. Genetic algorithms are used in the optimization phase of the identification algorithm to overcome the difficulty in the selection of initial values for parameter estimates. Validation analysis of the identified model is also presented. Identified model is shown to track the system response successfully. Following the linear model identification, identification of 3 dof nonlinear models are studied. Local identifiability analysis is done and optimal input is designed using the same procedure for linear model structure identification. Practical identifiability analysis is performed using Fisher Information Matrix. Physical parameters are estimated using the data from simulated experiments. High accuracy estimates are obtained. Methodology for nonlinear handling model identification is presented.
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Slomka, Stefan. "Multiple classifier structures for automatic speaker recognition under adverse conditions." Thesis, Queensland University of Technology, 1999.
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Riley, Gareth. "The development of a generic model for choosing a suitable traceability system for use in a manufacturing environment." Thesis, Stellenbosch : University of Stellenbosch, 2009. http://hdl.handle.net/10019.1/2813.
Full textAbstract:
Thesis (MScEng (Industrial Engineering))--University of Stellenbosch, 2009.<br>Traceability systems are capable of both tracking and tracing parts. They offer many
benefits to an organisation from assisting with recall applications to monitoring the
everyday workings of a production line or supply chain. There are numerous methods
able to act as traceability systems but only a few can be regarded as automatic and
unique identifiers.
Automatic traceability of individual entities is the future. It is already widely used by a
number of leading companies throughout different business sectors and wide mass
adoption is imminent. At present, they are slightly more expensive than the simpler
technologies but once mass produced, the cost will come down.
To completely understand how traceability systems are implemented, practical
experience is required. When starting a traceability project, there are a lot of different
options. The different systems offer their own set of advantages and some don’t work in
certain environments. It was for this reason that The Decision Making Model was
developed to assist users through the difficult initial stages of traceability implementation
(i.e. choosing the system most suitable to a particular environment).
This model was programmed in Excel and supplies the user with a number of questions
regarding the environment the system would work in as well as the user’s requirements.
The answers to these questions help the user work through the different types of
traceability options to eliminate unsuitable choices. The result is an easy to use program
designed with the ability to be upgraded as the technologies evolve.
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Phythian, Mark. "Speaker identification for forensic applications." Thesis, Queensland University of Technology, 1998. https://eprints.qut.edu.au/36079/3/__qut.edu.au_Documents_StaffHome_StaffGroupR%24_rogersjm_Desktop_36079_Digitised%20Thesis.pdf.
Full textAbstract:
A major application of Speaker Identification (SI) is suspect identification by voice. This thesis investigates techniques that can be used to improve SI technology as applied to suspect identification. Speech Coding techniques have become integrated into many of our modern
voice communications systems. This prompts the question - how are automatic speaker identification systems and modern forensic identification techniques affected by the introduction of digitally coded speech channels? Presented in this thesis are three separate studies investigating the effects of speech coding and compression on current speaker recognition techniques. A relatively new Spectral Analysis technique - Higher Order Spectral Analysis
(HOSA) - has been identified as a potential candidate for improving some aspects of forensic speaker identification tasks. Presented in this thesis is a study investigating the application of HOSA to improve the robustness of
current ASR techniques in the presence of additive Gaussian noise. Results from our investigations reveal that incremental improvements in each of these aspects related to automatic and forensic identification are achievable.
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Cagatay, Kartal. "Modeling, Identification And Real Time Position Control Of A Two-axis Gimballed Mirror System." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/2/12611668/index.pdf.
Full textAbstract:
This work focuses on modeling, parameter estimation, and real-time position control of a two axis Gimbaled Mirror System (GMS) which is designed and manufactured to move an IR spot generated by an Infra Red Scene Generator System (IRSGS) in two orthogonal axes (elevation and azimuth) within the IR scene which is also generated by the IRSGS.
Mathematical models of the GMS, the control system, and the disturbance torque originated from the movements of Flight Motion Simulator (FMS), on which the IRSGS will be mounted, are constructed using MATLAB®<br>/Simulink®<br>and MATLAB/Simulink/SimMechanics®<br>. Parameter estimations of the GMS and control system elements are achieved using MATLAB/Simulink Parameter Estimation Tool®<br>.
The controller tuning is performed using the developed mathematical models in MATLAB/Simulink environment. Optimized digital PID controllers are implemented in the real-time control system. Performances of the controllers for both GMS axes are evaluated by both real system tests and simulation runs<br>and the results of these runs are compared. Controller performances under the effect of disturbances are analyzed by using the mathematical models developed in the MATLAB/ Simulink environment.
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Le, Van Luong. "Identification de systèmes dynamiques hybrides : géométrie, parcimonie et non-linéarités." Phd thesis, Université de Lorraine, 2013. http://tel.archives-ouvertes.fr/tel-00874283.
Full textAbstract:
En automatique, l'obtention d'un modèle du système est la pierre angulaire des procédures comme la synthèse d'une commande, la détection des défaillances, la prédiction... Cette thèse traite de l'identification d'une classe de systèmes complexes, les systèmes dynamiques hybrides. Ces systèmes impliquent l'interaction de comportements continus et discrets. Le but est de construire un modèle à partir de mesures expérimentales d'entrée et de sortie. Une nouvelle approche pour l'identification de systèmes hybrides linéaires basée sur les propriétés géométriques des systèmes hybrides dans l'espace des paramètres est proposée. Un nouvel algorithme est ensuite proposé pour le calcul de la solution la plus parcimonieuse (ou creuse) de systèmes d'équations linéaires sous-déterminés. Celui-ci permet d'améliorer une approche d'identification basée sur l'optimisation de la parcimonie du vecteur d'erreur. De plus, de nouvelles approches, basées sur des modèles à noyaux, sont proposées pour l'identification de systèmes hybrides non linéaires et de systèmes lisses par morceaux.
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Le, Van Luong. "Identification de systèmes dynamiques hybrides : géométrie, parcimonie et non-linéarités." Electronic Thesis or Diss., Université de Lorraine, 2013. http://www.theses.fr/2013LORR0102.
Full textAbstract:
En automatique, l'obtention d'un modèle du système est la pierre angulaire des procédures comme la synthèse d'une commande, la détection des défaillances, la prédiction... Cette thèse traite de l'identification d'une classe de systèmes complexes, les systèmes dynamiques hybrides. Ces systèmes impliquent l'interaction de comportements continus et discrets. Le but est de construire un modèle à partir de mesures expérimentales d'entrée et de sortie. Une nouvelle approche pour l'identification de systèmes hybrides linéaires basée sur les propriétés géométriques des systèmes hybrides dans l'espace des paramètres est proposée. Un nouvel algorithme est ensuite proposé pour le calcul de la solution la plus parcimonieuse (ou creuse) de systèmes d'équations linéaires sous-déterminés. Celui-ci permet d'améliorer une approche d'identification basée sur l'optimisation de la parcimonie du vecteur d'erreur. De plus, de nouvelles approches, basées sur des modèles à noyaux, sont proposées pour l'identification de systèmes hybrides non linéaires et de systèmes lisses par morceaux<br>In automatic control, obtaining a model is always the cornerstone of the synthesis procedures such as controller design, fault detection or prediction... This thesis deals with the identification of a class of complex systems, hybrid dynamical systems. These systems involve the interaction of continuous and discrete behaviors. The goal is to build a model from experimental measurements of the system inputs and outputs. A new approach for the identification of linear hybrid systems based on the geometric properties of hybrid systems in the parameter space is proposed. A new algorithm is then proposed to recover the sparsest solutions of underdetermined systems of linear equations. This allows us to improve an identification approach based on the error sparsification. In addition, new approaches based on kernel models are proposed for the identification of nonlinear hybrid systems and piecewise smooth systems
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Stevanatto, Filho Luiz Carlos. "Identificação parcial da resposta em freqüência de sistemas multivariáveis e sintonia de controladores descentralizados." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2008. http://hdl.handle.net/10183/15739.
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Utilização de experimentos com relés para identificação de pontos da resposta em freqüência de sistemas multivariáveis quadrados e sintonia de controladores PID descentralizados.<br>It use relay experiments for square multivariable system frequency response and decentralized PID controller tunning.
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Andrade, Leonardo Henrique Sales de. "Contributo para a digitalização da indústria do mármore com identificação automática por sistemas RFID." Master's thesis, Universidade de Évora, 2021. http://hdl.handle.net/10174/30321.
Full textAbstract:
Este trabalho visa contribuir com estratégias inovadoras a aplicar á cadeia produtiva da
indústria do mármore, propondo novas abordagens tecnológicas, com a utilização de sistemas
de Identificação por Radiofrequência - RFID. As capacidades dinâmicas das etiquetas RFID
(read-write) permitem o acesso, através do UUI, ao armazenamento da caracterização física
dos blocos de pedra, de acordo com os respectivos testes elétricos, ultrassónicos e visão de
imagens tridimensionais. Estes parâmetros de caracterização dos blocos de pedra originais
que resultam de ensaios não destrutivos, analisando a estrutura interna das rochas, podem ser
armazenados em bases de dados, através da codificação permitida pelas etiquetas RFID, a fim
de otimizar os subsequentes processos de corte e processamento. A tecnologia de identificação
RFID, quando integrada numa rede de comunicação Ethernet, permite a comunicação automática
com equipamentos de corte e processamento, constituindo uma plataforma industrial inteligente,
integrando PCs (Computadores Pessoais) e PLCs (Controladores Lógicos Programáveis) no
contexto da indústria 4.0. Além disso, outra grande vantagem da tecnologia RFID ´e que ela
permite a rastreabilidade total do produto, permitindo que os consumidores finais invertam o
processo produtivo; CONTRIBUTION TO THE DIGITIZATION OF THE MARBLE INDUSTRY
WITH RFID IDENTIFICATION SYSTEMS
ABSTRACT:
This work aims to improve the marble industry production chain by proposing new technological
approaches using the Radio Frequency Identification - RFID - systems. The dynamic
capabilities of the RFID (read-write) tags allow the storage of the physical characterization of
stone blocks, through the UUI, according to the electrical, ultrasound and the three-dimensional
image tests. These characterization parameters of the stone blocks, resulting from non-destructive
tests, allow the knowledge of the internal structure of the rocks, which can be stored in databases,
coded by RFID-tags in order to optimize their subsequent cutting and transformation
processes. RFID identification technology when integrated into an ethernet communication
network enables automatic communication with cutting and processing equipment, building an
intelligent industrial platform, integrating PCs (Personal Computers) and PLCs (Programmable
Logic Controllers) within Industry 4.0 environment. Additionally, another huge advantage of
RFID technology is that it allows full product traceability, enabling end consumers to reverse
the production path.
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Mathapo, Kgabo Frans. "A software-defined radio implementation of maritime AIS." Thesis, Link to the online version, 2007. http://hdl.handle.net/10019/678.
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Moberg, Stig. "On Modeling and Control of Flexible Manipulators." Licentiate thesis, Linköping University, Linköping University, Automatic Control, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-10463.
Full textAbstract:
<p>Industrial robot manipulators are general-purpose machines used for industrial automation in order to increase productivity, flexibility, and quality. Other reasons for using industrial robots are cost saving, and elimination of heavy and health-hazardous work. Robot motion control is a key competence for robot manufacturers, and the current development is focused on increasing the robot performance, reducing the robot cost, improving safety, and introducing new functionalities. Therefore, there is a need to continuously improve the models and control methods in order to fulfil all conflicting requirements, such as increased performance for a robot with lower weight, and thus lower mechanical stiffness and more complicated vibration modes. One reason for this development of the robot mechanical structure is of course cost-reduction, but other benefits are lower power consumption, improved dexterity, safety issues, and low environmental impact.</p><p>This thesis deals with three different aspects of modeling and control of flexible, i.e., elastic, manipulators. For an accurate description of a modern industrial manipulator, the traditional flexible joint model, described in literature, is not sufficient. An improved model where the elasticity is described by a number of localized multidimensional spring-damper pairs is therefore proposed. This model is called the extended flexible joint model. This work describes identification, feedforward control, and feedback control, using this model.</p><p>The proposed identification method is a frequency-domain non-linear gray-box method, which is evaluated by the identification of a modern six-axes robot manipulator. The identified model gives a good description of the global behavior of this robot.</p><p>The inverse dynamics control problem is discussed, and a solution methodology is proposed. This methodology is based on a differential algebraic equation (DAE) formulation of the problem. Feedforward control of a two-axes manipulator is then studied using this DAE approach.</p><p>Finally, a benchmark problem for robust feedback control of a single-axis extended flexible joint model is presented and some proposed solutions are analyzed.</p>
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Olcer, Tuncay Ugurlu. "H2/h." Master's thesis, METU, 2013. http://etd.lib.metu.edu.tr/upload/12615636/index.pdf.
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In fin actuation systems, the performance of classical linear control systems is not satisfactory due to uncertainty of the system parameters and disturbances of the working medium. For this reason, sliding mode, H2 or H&infin<br>robust controllers are widely used in literature for such systems. However, use of such controllers results in very conservative system responses. Based on this fact, in this thesis, development of a more effective robust controller is aimed via integration of the optimum properties of the existent pure H2 and H&infin<br>type robust controllers. To achieve this, during the controller synthesizing procedure, some of the optimization parameters are weighted according to H2 norm minimization, and parameter uncertainties and other variables are weighted according to H&infin<br>theorem. First, the system set up to be controlled is physically constructed and performed system identification processes. Then, two different types of robust controllers H2 and H&infin<br>controllers are designed and tested over both the real system and simulation. Finally an H2/H&infin<br>mixed type controller synthesized and the results are compared with the outputs of the robust controllers of the previous step.
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Peters, Mathias. "Scheduling workflows to optimize for execution time." Thesis, Uppsala universitet, Institutionen för informatik och media, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-354464.
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Many functions in today’s society are immensely dependent on data. Data drives everything from business decisions to self-driving cars to intelligent home assistants like Amazon Echo and Google Home. To make good decisions based on data, of which exabytes are generated every day, somehow that data has to be processed. Data processing can be complex and time-consuming. One way of reducing the complexity is to create workflows that consist of several steps that together produce the right result. Klarna is an example of a company that relies on workflows for transforming and analyzing data. As a company whose core business involves analyzing customer data, being able to do those analyses faster will lead to direct business value in the form of more well-informed decisions. The workflows Klarna use are currently all written in a sequential form. However, workflows, where independent tasks are executed in parallel, are more performant than workflows where only one task is executed at any point in time. Due to limitations in human attention span, parallelized workflows are harder for humans to write, compared to sequential workflows. In this work, a computer application was created that automates the parallelization of a workflow to let humans write sequential workflows while still getting the performance of parallelized workflows. The application does this by taking a simple sequential workflow, identifies dependencies in the workflow and then schedules it in a way that is as parallel as possible given the identified dependencies. Such a solution has not been created before. However, experimental evaluation shows that parallelization of a sequential workflow used in daily production at Klarna can reduce execution time by up to 80%, showing that the application can bring value to Klarna and other organizations that use workflows to analyze big data.
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CARBONI, ANGELA. "Technical, economic and energetic competitiveness of rail-road combined transport: evaluation of the effects of possible ITS applications on intermodal terminal." Doctoral thesis, Politecnico di Torino, 2019. http://hdl.handle.net/11583/2732968.
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