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Dissertations / Theses on the topic 'Hidden objects'
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1
Reid, Sheri Lynn. "Search for hidden objects by pigeons: Place learning vs "object permanence"." Thesis, University of Ottawa (Canada), 1996. http://hdl.handle.net/10393/9707.
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Mental representation of hidden objects by pigeons was tested for. Experiment 1 used a series of Piagetian tests of "object permanence" to measure pigeons' capacity to find a stationary food target behind a screen. Performance on these tests did not differ significantly from chance in spite of manipulations designed to enhance the motivational value of the hidden object. Experiment 2 used operant contingencies to test whether pigeons could mentally represent a moving dot on a computer monitor that temporarily "disappeared" behind a screen. Two target durations were used (12 and 24 seconds) for the dot to move across a computer screen. Pigeons were reinforced if their first keypeck occurred when the dot was hidden but not if it occurred when the dot was visible. Phase 1 consisted of target-12 trials, phase 2 consisted of target-24 trials, and phase 3 consisted of alternating sessions of target-12 and target-24 trials. Results demonstrate that while pigeons were able to use timing strategies to respond correctly with an unconstrained choice method, evidence for the use of mental representations by pigeons was inconclusive. Both experiments are discussed in terms of the mechanisms used by pigeons to find hidden objects.
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Parkinson, Adam Douglas. "Encountering the hidden worlds of musical objects." Thesis, University of Newcastle upon Tyne, 2012. http://hdl.handle.net/10443/3407.
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This thesis articulates an approach to our musical interactions with sounds and technologies influenced by Object Oriented Philosophy and the thought of Gilles Deleuze. The research question is borne out of the practice itself and the questions it poses: how to make sense of my own relationship with sounds as a listener, improviser and composer, and how to understand my engagement with the technologies which mediate this relationship. The most prominent technology I encounter is the laptop, which throughout my practice is used as a musical instrument, and a large part of my research also involves the development of a sensor instrument which utilises the Apple iPhone. The research thus serves as an exploration of both the laptop-as-instrument and certain ‘post laptop’ possibilities, alongside the development of a framework within which to critically consider our relationships to these new instruments. Music involves multiple ‘objects’, a concept which includes (but is not limited to) sounds, songs, instruments, speakers, performers and listeners. Object Oriented Philosophy tells us that these objects are withdrawn: they possess ‘hidden worlds’ or reservoirs of potential that we do not exhaust through any one encounter. Sounds and instruments can be always be used in different ways and reveal different qualities through the networks they are placed in. Listening and playing are construed as being a challenge to find the hidden potentials and affordances in sounds, through changing the way we listen or recontextualising or reworking the sound itself: a range of different strategies for approaching sounds is discussed. I also bring this approach to new instruments - such as laptops, sensor instruments or electronics set-ups - asking what their unique affordances and ‘hidden worlds’ are, and how they might not be actualised should we approach them with fixed ideas about what instruments, performance and music are.
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Ma, Feng. "Discovery of hidden blazars inside quasars /." Digital version accessible at:, 2000. http://wwwlib.umi.com/cr/utexas/main.
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Gariepy, Genevieve. "Imaging light in motion and its application to tracking hidden objects." Thesis, Heriot-Watt University, 2016. http://hdl.handle.net/10399/3371.
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It is well known that light, the fastest entity in the universe, moves at a staggering speed of 300 million meters per second. The ability to stop its flight on a centimetre scale or lower requires a detector with temporal resolution of around a hundred picoseconds. Freezing light in motion at this scale is a feat worth achieving, as it leads to a variety of exciting applications, from observing dynamical light phenomena to measuring distances and depths with high precision, as in LIDAR technology. In the past decades, different technologies have been developed to image light in motion; in this thesis, we propose a new method that exploit a recently-developed single-photon detector technology to capture movies of light in motion at very low intensity levels. We use this method to develop novel imaging applications and detection techniques. In particular, this thesis reports on the observation and study of dynamical light phenomena such as laser propagation in air, laser-induced plasma, propagation in optical fibres and slow light. We also show how the ability to record light in motion can be used to capture light signals scattered from around an obstacle, leading to the ability to locate and track moving objects hidden from view.
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Barth, Jochen. "Search and exploration of hidden objects by great apes and young children." [Maastricht : Maastricht : Universiteit Maastricht] ; University Library, Maastricht University [Host], 2005. http://arno.unimaas.nl/show.cgi?fid=6376.
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Pandharkar, Rohit (Rohit Prakash). "Hidden object doppler : estimating motion, size and material properties of moving non-line-of-sight objects in cluttered environments." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/67783.
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Thesis (S.M.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2011.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 111-117).
The thesis presents a framework for Non-Line-of-Sight Computer Vision techniques using wave fronts. Using short-pulse illumination and a high speed time-of-flight camera, we propose algorithms that use multi path light transport analysis to explore the environments beyond line of sight. What is moving around the corner interests everyone including a driver taking a turn, a surgeon performing laparoscopy and a soldier entering enemy base. State of the art techniques that do range imaging are limited by (i) inability to handle multiple diffused bounces [LIDAR] (ii) Wavelength dependent resolution limits [RADAR] and (iii) inability to map real life objects [Diffused Optical Tomography]. This work presents a framework for (a) Imaging the changing Space-time-impulse-responses of moving objects to pulsed illumination (b) Tracking motion along with absolute positions of these hidden objects and (c) recognizing their default properties like material and size and reflectance. We capture gated space-time impulse responses of the scene and their time differentials allow us to gauge absolute positions of moving objects with knowledge of only relative times of arrival (as absolute times are hard to synchronize at femto second intervals). Since we record responses at very short time intervals we collect multiple readings from different points of illumination and thus capturing multi-perspective responses allowing us to estimate reflectance properties. Using this, we categorize and give parametric models of the materials around corner. We hope this work inspires further exploration of NLOS computer vision techniques.
by Rohit Pandharkar.
S.M.
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Maghrabi, Saud M. A. "Algorithms for the removal of hidden edges from computer representations of solid objects." Thesis, University of Hull, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.314689.
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Liau, Teh-Fu. "Digital signal processing for the detection of hidden objects using an FMCW radar." Thesis, Queen Mary, University of London, 1987. http://qmro.qmul.ac.uk/xmlui/handle/123456789/1591.
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This thesis deals with the detection of hidden objects using a short-range frequency-modulated continuous wave (FMCW) radar. The detection is carried out by examining the estimated Power Spectral Density (PSD) functions of sampled returns, the peaks of which theoretically correspond to the reflecting surfaces of hidden objects. Fourier and non-Fourier PSD estimation algorithms are applied to the radar returns to extract information on the hidden surfaces. The Fourier methods used are Direct, Blackman-Tukey, Bartlett, and Smoothed Periodograms. The different PSDs are compared, and the validity of each PSD is then discussed. The study is new for this type of radar and the results are used as references for other PSD estimations. Non-Fourier methods offer many advantages. Firstly the Autoregressive Process (AR) is used for this particular application. As well as PSDs the noise spectra are also produced to show the performance of the chosen models. An alternative approach to the conventional forward-backward residuals ( e. g. Burg's method) or autocorrelation and covariance methods ( as those used in speech analysis ) is introduced in this thesis. The stability and good resolution of the PSDs is obtained by a better estimation of the autocovariance coefficients (ACF) from the data available : averaging two p-shifted ACF calculated by covariance method. Once the covariance coefficients are found, the Levinson-Durbin recursive algorithm is used to get the model parameters and the PSDs. Two other non-conventional methods are also attempted to show the image of hidden objects. They are Pisarenko Harmonic Decomposition method and Prony energy spectrum density estimation. In addition to the one-dimensional processing stated above, this thesis extends it to two-dimensional cases, which give more information on the shape of hidden objects.
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Mareschal, Denis. "Visual tracking and the development of object permanence : a connectionist enquiry." Thesis, University of Oxford, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.389084.
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Smith, Simon Paul. "Towards a knowledge management methodology for articulating the role of hidden knowledges." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:32449230-a86a-453b-b9d4-dca2d0b7be3c.
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Knowledge Management Systems are deployed in organisations of all sizes to support the coordination and control of a range of intellectual assets, and the low cost infrastructures made available by the shift to ‘cloud computing’ looks to only increase the speed and pervasiveness of this move. However, their implementation has not been without its problems, and the development of novel interventions capable of supporting the mundane work of everyday organisational settings has ultimately been limited. A common source of trouble for those formulating such systems is said to be that some proportion of the knowledge held by a setting’s members is hidden from the undirected view of both The Organisation and its analysts - typically characterised as a tacit knowledge - and can therefore go unnoticed during the design and deployment of new technologies. Notwithstanding its utility, overuse of this characterisation has resulted in the inappropriate labelling of a disparate assortment of phenomena, some of which might be more appropriately re-specified as ‘hidden knowledges’: a standpoint which seeks to acknowledge their unspoken character without making any unwarranted claims regarding their cognitive status. Approaches which focus on the situated and contingent properties of the actual work carried out by a setting’s members - such as ethnomethodologically informed ethnography - have shown significant promise as a mechanism for transforming the role played by members’ practices into an explicit topic of study. Specifically they have proven particularly adept at noticing those aspects of members’ work that might ordinarily be hidden from an undirected view, such as the methodic procedures through which we can sometimes mean more than we can say in-just-so-many-words. Here - within the context of gathering the requirements for new Knowledge Management Systems to support the reuse of existing knowledge - the findings from the application of just such an approach are presented in the form of a Pattern Language for Knowledge Management Systems: a descriptive device that lends itself to articulating the role that such hidden knowledges are playing in everyday work settings. By combining these three facets, this work shows that it is possible to take a more meaningful approach towards noticing those knowledges which might ordinarily be hidden from view, and apply our new understanding of them to the design of Knowledge Management Systems that actively engage with the knowledgeable work of a setting’s members.
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Kecskemetry, Peter D. "Computationally intensive methods for hidden Markov models with applications to statistical genetics." Thesis, University of Oxford, 2014. https://ora.ox.ac.uk/objects/uuid:8dd5d68d-27e9-4412-868c-0477e438a2c5.
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In most fields of technology and science, the exponential increase of available data is an apparent trend. In genetics, the main contributor to this trend is the improving efficiency of sequencing technologies. While the Human Genome project focused on assembling a single reference sequence not long ago, now there are aims to sequence million genomes in upcoming projects. The consequent computational challenge is being able to utilise this wealth of data, which requires the development of sufficiently powerful methods for analysis. However, the speed of transistor-based computing processors has recently hit a power ceiling and developers can no longer rely on hardware improvements automatically providing performance improvements in software directly. The result is that analysis methods are failing to keep up with the speed of data generation, and at this age of exponential data explosion it is becoming critical to find any solution for improving the performance of statistical methods. One traditional approach is to apply approximations - often trading the quality of results for response time. Another approach is to achieve algorithmic optimisations for existing methods without sacrificing results. Unfortunately, the possibilities for purely algorithmic optimisations often tend to be limited. A third approach is to attempt to harness the computational power of the presently re-emerging field of parallel computing. While the theoretical performance of parallel platforms roughly follows Moore's law, exploiting the power of parallelisms requires significant effort during development and may not even be possible in certain applications. This work attempts to explore avenues for achieving high performance for Hidden Markov Models (HMMs) and HMM applications in population genetics. The second chapter of this thesis introduces a single-locus variant of the IMPUTE2 method for calling and phasing genotype variants based on genotype likelihood data. This method uses both approximations and algorithmic optimisations and achieves performance improvements without a considerable drop in accuracy. It is also aimed to be highly parallelisable. The third chapter presents GPGPU-focused parallelisation methods over the statespace for HMM algorithms specifically under the Li and Stephens model, which is a widely and successfully used approximation of the coalescent. Practical experiments show ×200-×6000 times acceleration with a CUDA implementation of the popular Chromopainter method, which is based on the Li and Stephens model. The last chapter explores the theoretical possibility of parallelising HMM algorithms across blocks of observations (inspired by but not limited to methods used in genetics). A novel view and derivation is presented for block parallelism, along with accompanying analyses of applicability and relevance. Performance analysis results indicate that the application of block-parallelism is expected to be highly relevant for most large-scale HMM applications on present-day computing platforms, while block-parallelism may become a necessity for utilising the improving power of parallel hardware in the close future.
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Menard, Karen. "Means-end Search for Hidden Objects by 6.5-month-old Infants: Examination of an Experiential Limitation Hypothesis." Thesis, University of Waterloo, 2005. http://hdl.handle.net/10012/749.
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Three experiments were conducted to investigate the hypothesis that young infants? failures to search for occluded objects arises, not from deficiencies in their object representations, but from limitations in experience with the physical world. Successful means-end search is typically found at 8 months of age and is traditionally taken as the hallmark of object permanence. However, recent evidence suggests that infants much younger than 8 months of age are able to represent and reason about objects that are no longer visible. In Experiment 1, successful means-end search was found for 8. 5-, but not 6. 5-month-old infants in a traditional task, but younger infants showed successful search ability when the task was made familiar to them in Experiment 2 (i. e. , when the toy and occluder are first presented as a single composite object), and when they were given the opportunity to watch a demonstration of the solution to the task in Experiment 3. These results are taken as evidence for the ?experiential limitation? hypothesis and suggest that young infants are more apt at solving manual search tasks than previously acknowledged.
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Isidoros, Konstantina. "Social transformation among Sahrāwī desert nomads : the hidden logic of Ḥassānīya socio-geographical networks." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:8ace3f92-82d0-4e0a-9dfe-ba96e3dcbc03.
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Scholarship on the Western Sahara conflict has long puzzled over an ‘extraordinary leap’ of Sahrāwī tribes to the status of refugees and citizens of an exiled nation-state. It has glossed over this process as a modernising and civilising act of detribalisation, applauded women’s recent political appearance within a sovereignty-solidarity discourse, yet simultaneously used an insecurity discourse to measure Sahrāwī ‘performance’ hypercritically from inside the nascent state’s corridors. This ethnographic study observes Sahrāwī political action differently, by looking out from inside the tent and through the eyes of women. The thesis re-examines Sahrāwī tribe to state transition using a new framework of women’s tents and circulating, veiled males. Drawing on two years of anthropological fieldwork, the significance of the tent emerges as the decision-making centre for both men and women whereby the domestic is the political. I argue that women must be analytically recognised as political architects, utilising and presiding over tents as a female political economy of affection that casts a centralised political constellation across the Sahara. Not only do these fresh insights of Sahrāwī strategic tribe-state symbiosis and tactical nomadic sedentarisation overturn received anthropological wisdom on the stele of ‘tribe’, but it is women and their tents that can offer explanations for the ‘leap’ from genealogical reckoning to nationalist consciousness. This study presents comparative ethnography to engage critically with anthropology’s ‘great debates’ and popularised tropes regarding veiling, patriarchy, gendered space and power, and ‘tribal’ society. A different analytical light is cast on the gendered use of the exoticised Middle Eastern ḥarīm and of new hybrid forms of human socio-political reorganisation that challenge Western default notions of nation and state to suggest the need to rethink ‘tribe’.
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Gamble, Christopher Thomas. "A Bayesian chromosome painting approach to detect signals of incomplete positive selection in sequence data : applications to 1000 genomes." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:e1f3b484-59b9-4703-ae09-67079408c424.
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Methods to detect patterns of variation associated with ongoing positive selection often focus on identifying regions of the genome with extended haplotype homozygosity - indicative of recently shared ancestry. Whilst these have been shown to be powerful they have two major challenges. First, these methods are constructed to detect variation associated with a classical selective sweep; a single haplotype background gets swept up to a higher than expected frequency given its age. Recently studies have shown that other forms of positive selection, e.g. selection on standing variation, may be more prevalent than previous thought. Under such evolution, a mutation that is already segregating in the population becomes beneficial, possibly as a result of an environmental change. The second challenge with these methods is that they base their inference on non-parametric tests of significance which can result in uncontrolled false positive rates. We tackle these problems using two approaches. First, by exploiting a widely used model in population genomics we construct a new approach to detect regions where a subset of the chromosomes are much more related than expected genome-wide. Using this metric we show that it is sensitive to both classical selective sweeps, and to soft selective sweeps, e.g. selection on standing variation. Second, building on existing methods, we construct a Bayesian test which bi-partitions chromosomes at every position based on their allelic type and tests for association between chromosomes carrying one allele and significantly reduced time to common ancestor. Using simulated data we show that this approach results in a powerful, fast, and robust approach to detect signals of positive selection in sequence data. Moreover by comparing our model to existing techniques we show that we have similar power to detect recent classical selective sweeps, and considerably greater power to detect soft selective sweeps. We apply our method, ABACUS, to three human populations using data from the 1000 Genome Project. Using existing and novel candidates of positive selection, we show that the results between ABACUS and existing methods are comparable in regions of classical selection, and are arguably superior in regions that show evidence for recent selection on standing variation.
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Cramer, Heather. "Teaching Children with Autism Three Different Questions." Thesis, University of North Texas, 2003. https://digital.library.unt.edu/ark:/67531/metadc4427/.
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Children with autism often exhibit deficits in question-asking. This study replicated and extended Williams, Donley, and Keller.s (2000) training package: a modeling and reinforcement procedure to teach the use of 3 different questions about hidden objects. Two boys, aged 13 and 12, with primary diagnoses of autism, participated. A multiple baseline design across questions was used. Both children learned to ask all three questions: .What.s that?. .Can I see (item name)?. and .Can I have (item name)?. Question-asking generalized to novel locations, people, and stimulus materials with minimal additional training. These results support the efficacy of this training package as an efficient way to teach children with autism to ask questions about objects in their environment.
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Khokar, Karan Hariharan. "Human Intention Recognition Based Assisted Telerobotic Grasping of Objects in an Unstructured Environment." Scholar Commons, 2013. http://scholarcommons.usf.edu/etd/4909.
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In this dissertation work, a methodology is proposed to enable a robot to identify an object to be grasped and its intended grasp configuration while a human is teleoperating a robot towards the desired object. Based on the detected object and grasp configuration, the human is assisted in the teleoperation task. The environment is unstructured and consists of a number of objects, each with various possible grasp configurations. The identification of the object and the grasp configuration is carried out in real time, by recognizing the intention of the human motion. Simultaneously, the human user is assisted to preshape over the desired grasp configuration. This is done by scaling the components of the remote arm end-effector motion that lead to the desired grasp configuration and simultaneously attenuating the components that are in perpendicular directions. The complete process occurs while manipulating the master device and without having to interact with another interface.
Intention recognition from motion is carried out by using Hidden Markov Model (HMM) theory. First, the objects are classified based on their shapes. Then, the grasp configurations are preselected for each object class. The selection of grasp configurations is based on the human knowledge of robust grasps for the various shapes. Next, an HMM for each object class is trained by having a skilled teleoperator perform repeated preshape trials over each grasp configuration of the object class in consideration. The grasp configurations are modeled as the states of each HMM whereas the projections of translation and orientation vectors, over each reference vector, are modeled as observations. The reference vectors are the ideal translation and rotation trajectories that lead the remote arm end-effector towards a grasp configuration. During an actual grasping task performed by a novice or a skilled user, the trained model is used to detect their intention. The output probability of the HMM associated with each object in the environment is computed as the user is teleoperating towards the desired object. The object that is associated with the HMM which has the highest output probability, is taken as the desired object. The most likely Viterbi state sequence of the selected HMM gives the desired grasp configuration. Since an HMM is associated with every object, objects can be shuffled around, added or removed from the environment without the need to retrain the models. In other words, the HMM for each object class needs to be trained only once by a skilled teleoperator.
The intention recognition algorithm was validated by having novice users, as well as the skilled teleoperator, grasp objects with different grasp configurations from a dishwasher rack. Each object had various possible grasp configurations. The proposed algorithm was able to successfully detect the operator's intention and identify the object and the grasp configuration of interest. This methodology of grasping was also compared with unassisted mode and maximum-projection mode. In the unassisted mode, the operator teleoperated the arm without any assistance or intention recognition. In the maximum-projection mode, the maximum projection of the motion vectors was used to determine the intended object and the grasp configuration of interest. Six healthy and one wheelchair-bound individuals, each executed twelve pick-and-place trials in intention-based assisted mode and unassisted mode. In these trials, they picked up utensils from the dishwasher and laid them on a table located next to it. The relative positions and orientations of the utensils were changed at the end of every third trial. It was observed that the subjects were able to pick-and-place the objects 51% faster and with less number of movements, using the proposed method compared to the unassisted method. They found it much easier to execute the task using the proposed method and experienced less mental and overall workloads. Two able-bodied subjects also executed three preshape trials over three objects in intention-based assisted and maximum projection mode. For one of the subjects, the objects were shuffled at the end of the six trials and she was asked to carry out three more preshape trials in the two modes. This time, however, the subject was made to change their intention when she was about to preshape to the grasp configurations. It was observed that intention recognition was consistently accurate through the trajectory in the intention-based assisted method except at a few points. However, in the maximum-projection method the intention recognition was consistently inaccurate and fluctuated. This often caused to subject to be assisted in the wring directions and led to extreme frustration. The intention-based assisted method was faster and had less hand movements. The accuracy of the intention based method did not change when the objects were shuffled. It was also shown that the model for intention recognition can be trained by a skilled teleoperator and be used by a novice user to efficiently execute a grasping task in teleoperation.
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Baker, Adam. "Temporal dynamics of resting state brain connectivity as revealed by magnetoencephalography." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:ad9a825f-7036-4597-89d3-a7dfc8bb0641.
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Explorations into the organisation of spontaneous activity within the brain have demonstrated the existence of networks of temporally correlated activity, consisting of brain areas that share similar cognitive or sensory functions. These so-called resting state networks (RSNs) emerge spontaneously during rest and disappear in response to overt stimuli or cognitive demands. In recent years, the study of RSNs has emerged as a valuable tool for probing brain function, both in the healthy brain and in disorders such as schizophrenia, Alzheimer’s disease and Parkinson’s disease. However, analyses of these networks have so far been limited, in part due to assumptions that the patterns of neuronal activity that underlie these networks remain constant over time. Moreover, the majority of RSN studies have used functional magnetic resonance imaging (fMRI), in which slow fluctuations in the level of oxygen in the blood are used as a proxy for the activity within a given brain region. In this thesis we develop the use of magnetoencephalography (MEG) to study resting state functional connectivity. Unlike fMRI, MEG provides a direct measure of neuronal activity and can provide novel insights into the temporal dynamics that underlie resting state activity. In particular, we focus on the application of non- stationary analysis methods, which are able to capture fast temporal changes in activity. We first develop a framework for preprocessing MEG data and measuring interactions within different RSNs (Chapter 3). We then extend this framework to assess temporal variability in resting state functional connectivity by applying time- varying measures of interactions and show that within-network functional connectivity is underpinned by non-stationary temporal dynamics (Chapter 4). Finally we develop a data driven approach based on a hidden Markov model for inferring short lived connectivity states from resting state and task data (Chapter 5). By applying this approach to data from multiple subjects we reveal transient states that capture short lived patterns of neuronal activity (Chapter 6).
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Attia, Emad N. "Hidden object reconstruction from acoustic slices." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq20815.pdf.
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Rosser, Gabriel A. "Mathematical modelling and analysis of aspects of bacterial motility." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:1af98367-aa2f-4af3-9344-8c361311b553.
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The motile behaviour of bacteria underlies many important aspects of their actions, including pathogenicity, foraging efficiency, and ability to form biofilms. In this thesis, we apply mathematical modelling and analysis to various aspects of the planktonic motility of flagellated bacteria, guided by experimental observations. We use data obtained by tracking free-swimming Rhodobacter sphaeroides under a microscope, taking advantage of the availability of a large dataset acquired using a recently developed, high-throughput protocol. A novel analysis method using a hidden Markov model for the identification of reorientation phases in the tracks is described. This is assessed and compared with an established method using a computational simulation study, which shows that the new method has a reduced error rate and less systematic bias. We proceed to apply the novel analysis method to experimental tracks, demonstrating that we are able to successfully identify reorientations and record the angle changes of each reorientation phase. The analysis pipeline developed here is an important proof of concept, demonstrating a rapid and cost-effective protocol for the investigation of myriad aspects of the motility of microorganisms. In addition, we use mathematical modelling and computational simulations to investigate the effect that the microscope sampling rate has on the observed tracking data. This is an important, but often overlooked aspect of experimental design, which affects the observed data in a complex manner. Finally, we examine the role of rotational diffusion in bacterial motility, testing various models against the analysed data. This provides strong evidence that R. sphaeroides undergoes some form of active reorientation, in contrast to the mainstream belief that the process is passive.
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Herman, Joseph L. "Multiple sequence analysis in the presence of alignment uncertainty." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:88a56d9f-a96e-48e3-b8dc-a73f3efc8472.
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Sequence alignment is one of the most intensely studied problems in bioinformatics, and is an important step in a wide range of analyses. An issue that has gained much attention in recent years is the fact that downstream analyses are often highly sensitive to the specific choice of alignment. One way to address this is to jointly sample alignments along with other parameters of interest. In order to extend the range of applicability of this approach, the first chapter of this thesis introduces a probabilistic evolutionary model for protein structures on a phylogenetic tree; since protein structures typically diverge much more slowly than sequences, this allows for more reliable detection of remote homologies, improving the accuracy of the resulting alignments and trees, and reducing sensitivity of the results to the choice of dataset. In order to carry out inference under such a model, a number of new Markov chain Monte Carlo approaches are developed, allowing for more efficient convergence and mixing on the high-dimensional parameter space. The second part of the thesis presents a directed acyclic graph (DAG)-based approach for representing a collection of sampled alignments. This DAG representation allows the initial collection of samples to be used to generate a larger set of alignments under the same approximate distribution, enabling posterior alignment probabilities to be estimated reliably from a reasonable number of samples. If desired, summary alignments can then be generated as maximum-weight paths through the DAG, under various types of loss or scoring functions. The acyclic nature of the graph also permits various other types of algorithms to be easily adapted to operate on the entire set of alignments in the DAG. In the final part of this work, methodology is introduced for alignment-DAG-based sequence annotation using hidden Markov models, and RNA secondary structure prediction using stochastic context-free grammars. Results on test datasets indicate that the additional information contained within the DAG allows for improved predictions, resulting in substantial gains over simply analysing a set of alignments one by one.
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Narter, Dana Beth 1967. "Infants' expectations about the spatial and physical properties of a hidden object." Diss., The University of Arizona, 1997. http://hdl.handle.net/10150/282389.
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The purpose of this project was to investigate which spatial and physical object properties 9-month-old infants would use to trace an object in time and space. The particular object characteristics of interest were size, location and features. A two-location task was used, with looking time as the dependent measure. Infants observed a small toy troll, which was subsequently occluded. When the two flaps were removed, the infants observed either a standard or a change event. During the standard event no change occurred (the small troll was revealed at the same location). During a change event, some sort of physical or spatial change took place; the object might have changed its size (the large troll was revealed at the same location), its location (the small troll was revealed at the other location), its features (the small bear was revealed at the same location), or some combination of these attributes. Infants only observed one type of change event, depending on which of the seven conditions they were assigned to. The findings from this study can be interpreted in terms of two default assumptions: the Same Location/Same Object Rule and the Different Location/Different Object Rule. Nine-month olds use size cues to inform them about object identity in both situations; additionally, they use featural cues to inform them in the second case.
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Reynaga, Barba Valeria. "Detecting Changes During the Manipulation of an Object Jointly Held by Humans and RobotsDetektera skillnader under manipulationen av ett objekt som gemensamt hålls av människor och robotar." Thesis, KTH, Skolan för datavetenskap och kommunikation (CSC), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-174027.
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In the last decades research and development in the field of robotics has grown rapidly. This growth has resulted in the emergence of service robots that need to be able to physically interact with humans for different applications. One of these applications involves robots and humans cooperating in handling an object together. In such cases, there is usually an initial arrangement of how the robot and the humans hold the object and the arrangement stays the same throughout the manipulation task. Real-world scenarios often require that the initial arrangement changes throughout the task, therefore, it is important that the robot is able to recognize these changes and act accordingly. We consider a setting where a robot holds a large flat object with one or two humans. The aim of this research project is to detect the change in the number of agents grasping the object using only force and torque information measured at the robot's wrist. The proposed solution involves defining a transition sequence of four steps that the humans should perform to go from the initial scenario to the final one. The force and torque information is used to estimate the grasping point of the agents with a Kalman filter. While the humans are going from one scenario to the other, the estimated point changes according to the step of the transition the humans are in. These changes are used to track the steps in the sequence using a hidden Markov model (HMM). Tracking the steps in the sequence means knowing how many agents are grasping the object. To evaluate the method, humans that were not involved in the training of the HMM were asked to perform two tasks: a) perform the previously defined sequence as is, and b) perform a deviation of the sequence. The results of the method show that it is possible to detect the change between one human and two humans holding the object using only force and torque information.
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Chidiac, Amy Maguire. "Hide & seek : objects of meaning /." Online version of thesis, 2009. http://hdl.handle.net/1850/11205.
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Orten, Burkay Birant. "Moving Object Identification And Event Recognition In Video Surveillamce Systems." Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12606294/index.pdf.
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This thesis is devoted to the problems of defining and developing the basic building blocks of an automated surveillance system. As its initial step, a background-modeling algorithm is described for segmenting moving objects from the background, which is capable of adapting to dynamic scene conditions, as well as determining shadows of the moving objects. After obtaining binary silhouettes for targets, object association between consecutive frames is achieved by a hypothesis-based tracking method. Both of these tasks provide basic information for higher-level processing, such as activity analysis and object identification. In order to recognize the nature of an event occurring in a scene, hidden Markov models (HMM) are utilized. For this aim, object trajectories, which are obtained through a successful track, are written as a sequence of flow vectors that capture the details of instantaneous velocity and location information. HMMs are trained with sequences obtained from usual motion patterns and abnormality is detected by measuring the distance to these models. Finally, MPEG-7 visual descriptors are utilized in a regional manner for object identification. Color structure and homogeneous texture parameters of the independently moving objects are extracted and classifiers, such as Support Vector Machine (SVM) and Bayesian plug-in (Mahalanobis distance), are utilized to test the performance of the proposed person identification mechanism. The simulation results with all the above building blocks give promising results, indicating the possibility of constructing a fully automated surveillance system for the future.
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Andrej, Patrik. "Zastřešení víceúčelového sportovního objektu." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2020. http://www.nusl.cz/ntk/nusl-409846.
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The subject of the master thesis is the design and assessment of the supporting roof steel structure on the building, which will be used for various sports events in Znojmo. The building has a rectangular floor plan with dimensions of 50 x 60 m. The height at the top is 15 m. The trusses are articulated on concrete columns. Structure stability ensures system of bracings. The work contains a static calculation of the main load-bearing elements, including the relevant joints. The roof and cladding consist of sandwich panels.
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Ejnestrand, Ida, and Linnéa Jakobsson. "Object Tracking based on Eye Tracking Data : A comparison with a state-of-the-art video tracker." Thesis, Linköpings universitet, Datorseende, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-166007.
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The process of locating moving objects through video sequences is a fundamental computer vision problem. This process is referred to as video tracking and has a broad range of applications. Even though video tracking is an open research topic that have received much attention during recent years, developing accurate and robust algorithms that can handle complicated tracking tasks and scenes is still challenging. One challenge in computer vision is to develop systems that like humans can understand, interpret and recognize visual information in different situations. In this master thesis work, a tracking algorithm based on eye tracking data is proposed. The aim was to compare the tracking performance of the proposed algorithm with a state-of-the-art video tracker. The algorithm was tested on gaze signals from five participants recorded with an eye tracker while the participants were exposed to dynamic stimuli. The stimuli were moving objects displayed on a stationary computer screen. The proposed algorithm is working offline meaning that all data is collected before analysis. The results show that the overall performance of the proposed eye tracking algorithm is comparable to the performance of a state-of-the-art video tracker. The main weaknesses are low accuracy for the proposed eye tracking algorithm and handling of occlusion for the video tracker. We also suggest a method for using eye tracking as a complement to object tracking methods. The results show that the eye tracker can be used in some situations to improve the tracking result of the video tracker. The proposed algorithm can be used to help the video tracker to redetect objects that have been occluded or for some other reason are not detected correctly. However, ATOM brings higher accuracy.
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Andersson, Maria, Fredrik Gustafsson, Louis St-Laurent, and Donald Prevost. "Recognition of Anomalous Motion Patterns in Urban Surveillance." Linköpings universitet, Reglerteknik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-93983.
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We investigate the unsupervised K-means clustering and the semi-supervised hidden Markov model (HMM) to automatically detect anomalous motion patterns in groups of people (crowds). Anomalous motion patterns are typically people merging into a dense group, followed by disturbances or threatening situations within the group. The application of K-means clustering and HMM are illustrated with datasets from four surveillance scenarios. The results indicate that by investigating the group of people in a systematic way with different K values, analyze cluster density, cluster quality and changes in cluster shape we can automatically detect anomalous motion patterns. The results correspond well with the events in the datasets. The results also indicate that very accurate detections of the people in the dense group would not be necessary. The clustering and HMM results will be very much the same also with some increased uncertainty in the detections.Funding Agencies|Vinnova (Swedish Governmental Agency for Innovation Systems) under the VINNMER program||
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Karaman, Svebor. "Indexation de la vidéo portée : application à l’étude épidémiologique des maladies liées à l’âge." Thesis, Bordeaux 1, 2011. http://www.theses.fr/2011BOR14402/document.
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Le travail de recherche de cette thèse de doctorat s'inscrit dans le cadre du suivi médical des patients atteints de démences liées à l'âge à l'aide des caméras videos portées par les patients. L'idée est de fournir aux médecins un nouvel outil pour le diagnostic précoce de démences liées à l'âge telles que la maladie d'Alzheimer. Plus précisément, les Activités Instrumentales du Quotidien (IADL: Instrumental Activities of Daily Living en anglais) doivent être indexées automatiquement dans les vidéos enregistrées par un dispositif d'enregistrement portable.Ces vidéos présentent des caractéristiques spécifiques comme de forts mouvements ou de forts changements de luminosité. De plus, la tâche de reconnaissance visée est d'un très haut niveau sémantique. Dans ce contexte difficile, la première étape d'analyse est la définition d'un équivalent à la notion de « plan » dans les contenus vidéos édités. Nous avons ainsi développé une méthode pour le partitionnement d'une vidéo tournée en continu en termes de « points de vue » à partir du mouvement apparent.Pour la reconnaissance des IADL, nous avons développé une solution selon le formalisme des Modèles de Markov Cachés (MMC). Un MMC hiérarchique à deux niveaux a été introduit, modélisant les activités sémantiques ou des états intermédiaires. Un ensemble complexe de descripteurs (dynamiques, statiques, de bas niveau et de niveau intermédiaire) a été exploité et les espaces de description joints optimaux ont été identifiés expérimentalement.Dans le cadre de descripteurs de niveau intermédiaire pour la reconnaissance d'activités nous nous sommes particulièrement intéressés aux objets sémantiques que la personne manipule dans le champ de la caméra. Nous avons proposé un nouveau concept pour la description d'objets ou d'images faisant usage des descripteurs locaux (SURF) et de la structure topologique sous-jacente de graphes locaux. Une approche imbriquée pour la construction des graphes où la même scène peut être décrite par plusieurs niveaux de graphes avec un nombre de nœuds croissant a été introduite. Nous construisons ces graphes par une triangulation de Delaunay sur des points SURF, préservant ainsi les bonnes propriétés des descripteurs locaux c'est-à-dire leur invariance vis-à-vis de transformations affines dans le plan image telles qu'une rotation, une translation ou un changement d'échelle.Nous utilisons ces graphes descripteurs dans le cadre de l'approche Sacs-de-Mots-Visuels. Le problème de définition d'une distance, ou dissimilarité, entre les graphes pour la classification non supervisée et la reconnaissance est nécessairement soulevé. Nous proposons une mesure de dissimilarité par le Noyau Dépendant du Contexte (Context-Dependent Kernel: CDK) proposé par H. Sahbi et montrons sa relation avec la norme classique L2 lors de la comparaison de graphes triviaux (les points SURF).Pour la reconnaissance d'activités par MMC, les expériences sont conduites sur le premier corpus au monde de vidéos avec caméra portée destiné à l'observation des d'IADL et sur des bases de données publiques comme SIVAL et Caltech-101 pour la reconnaissance d'objetsThe research of this PhD thesis is fulfilled in the context of wearable video monitoring of patients with aged dementia. The idea is to provide a new tool to medical practitioners for the early diagnosis of elderly dementia such as the Alzheimer disease. More precisely, Instrumental Activities of Daily Living (IADL) have to be indexed in videos recorded with a wearable recording device.Such videos present specific characteristics i.e. strong motion or strong lighting changes. Furthermore, the tackled recognition task is of a very strong semantics. In this difficult context, the first step of analysis is to define an equivalent to the notion of “shots” in edited videos. We therefore developed a method for partitioning continuous video streams into viewpoints according to the observed motion in the image plane.For the recognition of IADLs we developed a solution based on the formalism of Hidden Markov Models (HMM). A hierarchical HMM with two levels modeling semantic activities or intermediate states has been introduced. A complex set of features (dynamic, static, low-level, mid-level) was proposed and the most effective description spaces were identified experimentally.In the mid-level features for activities recognition we focused on the semantic objects the person manipulates in the camera view. We proposed a new concept for object/image description using local features (SURF) and the underlying semi-local connected graphs. We introduced a nested approach for graphs construction when the same scene can be described by levels of graphs with increasing number of nodes. We build these graphs with Delaunay triangulation on SURF points thus preserving good properties of local features i.e. the invariance with regard to affine transformation of image plane: rotation, translation and zoom.We use the graph features in the Bag-of-Visual-Words framework. The problem of distance or dissimilarity definition between graphs for clustering or recognition is obviously arisen. We propose a dissimilarity measure based on the Context Dependent Kernel of H. Sahbi and show its relation with the classical entry-wise norm when comparing trivial graphs (SURF points).The experiments are conducted on the first corpus in the world of wearable videos of IADL for HMM based activities recognition, and on publicly available academic datasets such as SIVAL and Caltech-101 for object recognition
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Hubený, Marek. "Koncepty strojového učení pro kategorizaci objektů v obrazu." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2017. http://www.nusl.cz/ntk/nusl-316388.
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This work is focused on objects and scenes recognition using machine learning and computer vision tools. Before the solution of this problem has been studied basic phases of the machine learning concept and statistical models with accent on their division into discriminative and generative method. Further, the Bag-of-words method and its modification have been investigated and described. In the practical part of this work, the implementation of the Bag-of-words method with the SVM classifier was created in the Matlab environment and the model was tested on various sets of publicly available images.
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Emmerich, Kamper Theresa. "Determining traditional skin processing technologies : the macroscopic and microscopic characteristics of experimental samples, prehistoric archaeological finds and ethnographic objects." Thesis, University of Exeter, 2015. http://hdl.handle.net/10871/22073.
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The importance of skin processing technologies, in the history and dispersal of humankind around the planet cannot be overstated. This area of material culture is often underrepresented as a research topic, and has been hampered, in part, by the lack of a systematic analysis methodology targeted at specifically this material type. This research aimed to develop a methodology for determining the tanning technologies in use during prehistory, from extant archaeologically recovered processed skin objects. The methodology is a product of macroscopic and microscopic observations of a large sample reference collection, used to produce a database of defining characteristics and tendencies for each of six tannage types. The sample collection is made up of twenty-two species identified as economically important from both Europe and North America. Six sample pieces of skin were taken from a single individual of each of the twenty-two species, and processed using six tanning technologies, the use of which covered a large geographic area and time frame. A second reference collection of clothing and utilitarian items, made from traditionally processed skins, was used to add a section of in-life use traces to the database of discriminating traits. The developed methodology was tested by examining archaeologically recovered and ethnographically collected skin objects, from museum collections across North America and Europe. Objects from many different preservation contexts, including wet, dry, and frozen sites were analysed to determine whether or not the discriminating traits survived interment. It was found that defining characteristics and tendencies do exist between the main tannage technologies, and can be recorded at multiple levels of observation. The analysis of skin objects in museum collections confirmed that at least some defining characteristics and tendencies survived in all preservation contexts. In addition, the preservation of in-life use traces proved to be diagnostic of not only tannage type, but small sections of chaîne opératoire and object biography as well. Overall, this research has demonstrated that archaeologically preserved objects made from processed skin can provide information about the tannage technologies in use prehistorically, as well as more detailed information such as manufacturing sequences and the conditions of use an object was subjected to. Thus, analysis of this nature can be used to access information on a more individual level than previously believed.
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Petetin, Yohan. "Algorithmes de restauration bayésienne mono- et multi-objets dans des modèles markoviens." Phd thesis, Institut National des Télécommunications, 2013. http://tel.archives-ouvertes.fr/tel-00939083.
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Cette thèse est consacrée au problème d'estimation bayésienne pour le filtrage statistique, dont l'objectif est d'estimer récursivement des états inconnus à partir d'un historique d'observations, dans un modèle stochastique donné. Les modèles stochastiques considérés incluent principalement deux grandes classes de modèles : les modèles de Markov cachés et les modèles de Markov à sauts conditionnellement markoviens. Ici, le problème est abordé sous sa forme générale dans la mesure où nous considérons le problème du filtrage mono- et multi objet(s), ce dernier étant abordé sous l'angle de la théorie des ensembles statistiques finis et du filtre " Probability Hypothesis Density ". Tout d'abord, nous nous intéressons à l'importante classe d'approximations que constituent les algorithmes de Monte Carlo séquentiel, qui incluent les algorithmes d'échantillonnage d'importance séquentiel et de filtrage particulaire auxiliaire. Les boucles de propagation mises en jeux dans ces algorithmes sont étudiées et des algorithmes alternatifs sont proposés. Les algorithmes de filtrage particulaire dits " localement optimaux ", c'est à dire les algorithmes d'échantillonnage d'importance avec densité d'importance conditionnelle optimale et de filtrage particulaire auxiliaire pleinement adapté sont comparés statistiquement, en fonction des paramètres du modèle donné. Ensuite, les méthodes de réduction de variance basées sur le théorème de Rao-Blackwell sont exploitées dans le contexte du filtrage mono- et multi-objet(s) Ces méthodes, utilisées principalement en filtrage mono-objet lorsque la dimension du vecteur d'état à estimer est grande, sont dans un premier temps étendues pour les approximations Monte Carlo du filtre Probability Hypothesis Density. D'autre part, des méthodes de réduction de variance alternatives sont proposées : bien que toujours basées sur le théorème de Rao-Blackwell, elles ne se focalisent plus sur le caractère spatial du problème mais plutôt sur son caractère temporel. Enfin, nous abordons l'extension des modèles probabilistes classiquement utilisés. Nous rappelons tout d'abord les modèles de Markov couple et triplet dont l'intérêt est illustré à travers plusieurs exemples pratiques. Ensuite, nous traitons le problème de filtrage multi-objets, dans le contexte des ensembles statistiques finis, pour ces modèles. De plus, les propriétés statistiques plus générales des modèles triplet sont exploitées afin d'obtenir de nouvelles approximations de l'estimateur bayésien optimal (au sens de l'erreur quadratique moyenne) dans les modèles à sauts classiquement utilisés; ces approximations peuvent produire des estimateurs de performances comparables à celles des approximations particulaires, mais ont l'avantage d'être moins coûteuses sur le plan calculatoire
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Fofack, Tsabou Rhoda Lucie. "La société des eaux cachées du Saïss : l’analyse d‘un basculement autour de l’extraction des eaux souterraines profondes au Maroc." Thesis, Paris 10, 2018. http://www.theses.fr/2018PA100017.
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L’usage des eaux souterraines est à l’origine de l’expansion de l’économie agricole du Saïss, une région située au Nord du Maroc. Bien que cachées dans les sous-sols, les eaux souterraines de l’aquifère du même nom sont mises en visibilité par les objets techniques, intermédiaires indispensables à leur exploitation. D’une grande diversité, ces objets incluent les ouvrages d’exhaure (puits, forages, puits-forés) et leurs équipements (moteurs et pompes). D’un objet technique à l’autre, les transitions techniques qui traversent la région marquent le basculement des usages sur la nappe, des eaux souterraines superficielles aux eaux profondes. Au-delà des conditions hydrologiques et des pratiques de pompage qui changent, ce basculement témoigne du passage entre deux mondes sociaux spécifiques : un « monde de la pénurie » qui repose sur l’usage des puits et des eaux de la nappe phréatique ; et un « monde de l’abondance » où les forages permettent d’atteindre les ressources en eau de la nappe profonde, plus facilement exploitables, avec des débits plus importants et plus constants. L’évolution entre les deux mondes n’est pas linéaire, apparentée à une forme d’hybridité plutôt qu’à une rupture car leurs frontières sont rendues à la fois mouvantes et poreuses par les agriculteurs et des artisans innovants. En se constituant en objets de réseaux qui mettent en contact et créent des interdépendances entre les acteurs, les objets techniques dessinent un tissu réticulaire dont la maille ne relève pas de façon immédiate d’un lien territorial. La thèse explore ce que construit socialement la dynamique d’exploitation des ressources en eau souterraine, en caractérisant le type d’assemblages du social qui est généré - tout en y contribuant- par l’usage d’une ressource individualisée. L’analyse des mécanismes de récupération et la transformation des moteurs d’extraction révèle une société en émergence dont les systèmes d’échanges et de communication sont basés sur l’institution sociale du « bazar ». Structure sociale et culturelle traditionnelle dans les sociétés marocaines et orientales en général, le « bazar » offre des propriétés qui sont réinvesties de nos jours pour façonner les interrelations autour d’objets techniques nouveaux. En périphérie de ces processus, les acteurs publics contribuent à la réification des mondes sociaux, en disqualifiant le monde des puits pour encourager le monde « plus rationnel et mieux maîtrisé » des forages. L’approche de cette société des eaux cachées par l’intermédiaire de la technique et du rapport à l’eau souterraine se révèle d’une grande richesse, et capable de rendre visibles et explicites des dynamiques sociopolitiques caractéristiques du Maghreb contemporain. On voit alors se dessiner dans la relation ressources naturelles-objets techniques-acteurs des lignes de fracture sociologique entre monde de la ruralité souvent perçu par les acteurs publics comme « en retard » sur le développement et monde de la modernité qui encourage la course aux nouvelles technologies et à la technicitéGroundwater-based irrigation enabled the development of a dynamic agricultural economy in the Saïss plain, located in the north of Morocco. Hidden in the aquifer system, the groundwater resources are made visible by technical objects used for their extraction. These techniques are multiple, including dug wells, tube-wells, and their equipment: motors and pumps. The shift from one technique to the other brought about major agrarian transitions in the region accompanied by a change of groundwater uses by switching from the shallow phreatic aquifer to the deep Liassic aquifer. Beyond changes over the hydrological context and practices of pumping, the change in the uses of the aquifer also shows the shift between two specific social worlds around groundwater exploitation. A “world of scarcity” based on the use of dug wells and the shallow aquifer; and a “world of abundance” where tube-wells can easily pump in the deep Liassic aquifer with its large and more regular flow rate. From one social world to another, the shift is neither a one-way process nor a rupture. On the contrary, their frontiers and limits remain flexible and porous due to the movements of farmers and artisans. By becoming objects within networks that create links and interdependences between actors, techniques are constitutive of a socio-technical network regardless of any direct territorial link with the aquifer. The thesis explores what is socially constructed through the dynamics of groundwater exploitation, by characterizing types of social assemblages generated by the uses of an individualized resource. The analysis of mechanisms around the recycling and transformation of extractive motors reveals an emerging society where relationships between actors of the market are based on a “bazaar economy”. Used to describe and analyse the social, economic and cultural structure in traditional Moroccan societies and oriental societies in general, the properties of the bazaar economy have been reorganised nowadays to organize interrelations between new technical objects. In this system, public actors contribute to the differentiation between the two social worlds around groundwater exploitation, trying to marginalize the social world of wells and supporting the “more rational and tamed” social world of tube wells. Understanding the society of hidden waters by the mediation of techniques and through the relationships of actors to groundwater makes visible the socio-political dynamics in contemporary North Africa. The relation between natural resources-techniques-actors also reveal sociological frontiers between the world of rurality considered by public actors as being “behind” in the economic development of the Nation; and the world of modernity or new technologies which is ahead in this development
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Rocher, Gérald. "Évaluation de l’effectivité des systèmes ambiants." Thesis, Université Côte d'Azur, 2020. http://www.theses.fr/2020COAZ4003.
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D’un environnement fermé, contrôlé et négligeant toutes perturbations extérieures, le traitement de l’information est aujourd’hui exposé à la complexité et aux aléas de l’environnement physique, ouvert et non contrôlé. En effet, concrétisée par les progrès réalisés autour des communications sans fil, du stockage de l’énergie et de la miniaturisation des composants informatiques, la fusion des mondes physiques et numériques est une réalité qui s’incarne dans les systèmes dits ambiants. Au coeur de ces systèmes, les objets physiques de la vie quotidienne sont transcendés par des moyens informatiques et électroniques de traitement de l’information (actionneurs, capteurs, processeurs, etc.) offrant toujours plus de perspectives d’interactions entre les mondes physiques et numériques. Cette évolution convoque cependant une rupture épistémologique. Devenus complexes par leur fusion avec l’environnement physique, il ne s’agit plus de prédire in silico le comportement de tels systèmes à partir de modèles établis sur la base d’une connaissance supposée complète et fiable. Au contraire, conscient de la complexité intrinsèque de ces systèmes et de l’incapacité d’en obtenir un modèle fiable, il convient de s’assurer in vivo de l’effectivité de la réalisation de leurs finalités. Car, sans modèle fiable sur lequel bâtir des lois de contrôle, le comportement des systèmes ambiants est susceptible de dériver jusqu’à ne plus produire les effets attendus.Les travaux de cette thèse se proposent d’apporter une solution à cette problématique sur la base d’une approche méthodologique qui trouve ses fondements dans la systémique. Résultat de cette approche, le modèle systémique d’un système ambiant traduit ses finalités. Il répond à la question « qu’est-ce que le système ambiant doit faire ? ». À partir de ce modèle et de l’observation des effets produits dans l’environnement, la notion d’effectivité des systèmes ambiants est alors formalisée dans le cadre de la théorie de la mesure. Un ensemble de mesures est appliqué à cette formalisation (probabilités, possibilités et fonctions de croyance dans le cadre du modèle des croyances transférables) et les résultats sont discutés. Ces résultats ouvrent de nombreuses perspectives. Dans le contexte des méthodes agiles de développement logiciel pour systèmes ambiants, l’évaluation de l’effectivité pourra s’inscrire dans une démarche de tests continus. Dans celui des systèmes auto-adaptatifs, elle pourra être utilisée comme indicateur de récompense, d’erreur, etc. Dans le cas où le modèle systémique représente le comportement préféré d’un système ambiant, l’évaluation de l’effectivité s’apparente à un indicateur de la qualité de l’expérience des utilisateurs en interaction avec le systèmeFrom a closed and controlled environment, neglecting all the external disturbances, information processing is now exposed to the complexity and the hazards of the physical environment, open and uncontrolled. Indeed, as a result of the progresses made on wireless communications, energy storage and the miniaturization of computer components, the fusion of the physical and digital worlds is a reality embodied in so-called ambient systems. At the heart of these systems, everyday objects are transcended by computer and electronic information processing means (actuators, sensors, processors, etc.) offering new perspectives of interactions between the physical and digital worlds.This evolution, however, calls for an epistemological break. Being complex by their fusion with the physical environment, it is no longer a matter of predicting in silico the behavior of such systems from models established on the basis of a knowledge supposed to be complete and reliable. On the contrary, aware of the intrinsic complexity of these systems and the inability to obtain a reliable model, it is necessary to ensure their effectiveness in vivo. Indeed, without a reliable model of these systems on which to build control laws, their behavior is likely to drift until it no longer produces the expected effects.This thesis proposes to provide a solution to this problem on the basis of a methodological approach based on the systemic principles. As a result of this approach, the systemic model of an ambient system answers the question “what does the ambient system have to do?”. From this model and the observation of the effects produced in the environment, the notion of effectiveness is then formalized within the framework of the measure theory. A set of measures is applied to this formalization (probabilities, possibilities and belief functions in the framework of the transferable belief model) and the results are discussed.The results of this work are opening up numerous perspectives. In the context of agile software development methods for ambient systems, the evaluation of effectiveness can be part of a continuous testing process. In the case of self-adaptive systems, it can be used as an indicator of reward, error, etc. In the case where the systemic model represents the preferred behavior of an ambient system, the evaluation of the effectiveness is like an indicator of the quality of the user experience interacting with the system
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Mccall, Daniel D. "Object representation and means/ends coordination in 8-month-old infants' search for hidden objects." 1996. https://scholarworks.umass.edu/theses/2298.
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Shinskey, Jeanne Louise. "Why do young infants fail to search for hidden objects?" 1999. https://scholarworks.umass.edu/dissertations/AAI9950211.
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Infants less than 8 months old appear to lack the concept of object permanence because they fail to search for hidden objects. However, when looking rather than reaching is assessed, infants appear to have object permanence long before 8 months. One explanation for the discrepancy is that young infants lack the means-end motor skill to retrieve objects hidden by covers. The present research tested the object permanence deficit hypothesis against the means-end deficit hypothesis. Direct-reach search tasks were used, which should result in increased search by young infants if the means-end deficit hypothesis is correct. In Experiment 1, 6- and 10-month-old infants were presented with an object visible in water, partly visible in milk hidden in milk, or hidden under a cloth. As predicted by the object permanence deficit hypothesis, 6-month-old infants were less likely to search when the object was hidden than when it was visible or partly visible, but there were no differences at 10 months. The means-end deficit hypothesis prediction that younger infants would be less likely to search when the object was hidden by a cloth than when it was hidden by milk was not confirmed. In Experiment 2, 6- and 10-month-old infants were presented with an object visible behind a transparent curtain, partly visible through a hole in an opaque curtain, partly visible (fit flashlight) under a cloth, and hidden behind a completely opaque curtain. As predicted by the object permanence deficit hypothesis, 6-month-old infants were less likely to search when the object was hidden than when it was visible or partly visible, but there were almost no differences at 10 months. Unexpectedly, measures of locomotor ability were not reliably related to infants' search at 6 months. In a comparison of the cloth event of Experiment 1 and the flashlight event of Experiment 2, half the results indicated that 6-month-old infants were more likely to search in the partly visible event. The results are more consistent with the object permanence deficit hypothesis than with the means-end deficit hypothesis.
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Chen, Wei-nan, and 陳威男. "Identifying Structured Resource Objects on the Web Using Hidden Markov Model." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/18131734731450988936.
Full textAbstract:
碩士國立成功大學
資訊工程學系碩博士班
97
There are a lot of usuful web resources for users on the Web. However, users can only use keywords to search in general search engines, and usually have to find the web resources they want by themselves. In fact, search engines can not response the user demand effectively. We observed that some textual web resources are structured. Those web resources are a set of instructions for making, preparing or doing something, and they are made by sequential sentences. We called this kind of web resources sequential structured resource objects. In order to identify sequential structured resource objects, we proposed a Sequential Structured Resource Objects Identification Model to learn the structure of sequential structured resource objects then identify them on the Web. In this paper, we collected three kinds of sequential structured resource objects to training the model . Our model can effectively identify sequential structured resource objects on the Web in all the three web resources.
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Tseng, Hsiao-Yu, and 曾筱喻. "The Effects of Hidden Objects Games on English Vocabulary Learning for 5th Grade Students in Elementary School." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/47919594703162378246.
Full textAbstract:
碩士國立臺灣師範大學
創造力發展碩士在職專班
104
The purpose of this study is to explore the effects of hidden objects games on English vocabulary learning for students in OO elementary school in New Taipei city. In this study, independent variables focus on students’ FIFD cognitive styles and English learning proficiency levels. The dependent variables are cognitive load, English learning trait anxiety, state anxiety and flow experience. The method of this study is experiment-correlated. It adopted “purposive sampling” to choose 181 fifth-grade students as the participants. They took part in “hidden objects games” learning courses during English flexible hours every week. This study lasted for ten weeks. The participants experienced the game at most five times. Before and after hidden objects games, students were required to do the pre-test and post-test to know their vocabulary learning performance and their progress each time. Besides, Group Embedded Figure Test (GEFT) was used to understand students’ FIFD cognitive styles, and Questionnaires of this study included “English learning trait anxiety scale”, “state anxiety scale”, “cognitive load scale” and “flow experience.” To ensure the validity and reliability, all the scales were examined by item analysis and item discrimination. This study aimed to investigate the difference in performance among different FIFD cognitive-style students and students’ English proficiency levels, and explore the correlation of all variables. Moreover, this study intended to find out which variables are predictable for students’ score of English vocabulary post-test. In order to understand the effects, the quantification research data were analyzed by SPSS 22.0, including independent samples t -test, correlated samples t –test, correlation analysis and stepwise regression analysis. The major findings are as follows: 1. Stduents have made significantly prograss before and after experiencing hidden object games learning. 2. FD cognitive style’s cognitive load is significantly higher, and their amount of progress is lower. 3. Lower proficiency level’s cognitive load and amount of progress are significantly higher. 4. FD cognitive style’s state anxiety is significantly higher. 5. Lower proficiency level’s English learning trait anxiety and state anxiety are significantly higher. 6. Higher proficiency level’s flow experience are significantly higher. 7. FIFD cognitive styles are negatively correlated with English learning trait anxiety, cognitive load and state anxiety. 8. FIFD cognitive styles are positively correlated with flow experience. 9. Students’ English proficiency levels are negatively correlated with English learning trait anxiety, cognitive load and state anxiety. 10. FIFD cognitive styles, state anxiety and English learning anxiety could significantly predict English vocabulary post-test scores. The results of this study provided some suggestions for English teaching and future study as a reference. To sum up, adopting hidden objects games is an effective way to motivate students’ English vocabulary learning by integrating ACT-R modules. Even lower achievers made progress before and after. Mostly it helps reduce student’ learning state anxiety. Therefore, it might be used on remedial teaching. Also, different FIFD cognitive styles and English proficiency levels students behaves differently on learning anxiety, cognitive load and flow experience. For future study, researcher can focus more on the issue of arousing students’ flow experience--how to balance their “skill” and “challenge,” control their learning anxiety by using qualitative research method.
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Robin, Daniel J. "Infant motor planning and prediction: Reaching for a hidden moving object." 1996. https://scholarworks.umass.edu/dissertations/AAI9709645.
Full textAbstract:
The importance of continuous sight of the target in 7.5 month old infants' reaching was explored in a task that addressed the issues of infants' ability to anticipate and to retain information about the properties of a hidden object. Barriers and darkness were used to investigate infants' ability to compensate for the physical and visual obstruction of a target object in a reaching task. Infants' ability to intercept a moving object with a partially obscured trajectory was tested. Thirty 7.5 month old infants were presented with a graspable object that moved in a straight-line path through their reaching space. In some conditions the object was obscured by a barrier or by darkness for one second just prior to moving within reach, and infants' frequency of reaching and success at contacting the object were used to evaluate their performance. Further analyses of the infants' looking behavior and of the path of their reaching hand helped to clarify the reasons underlying their successes and failures. Infants showed some ability to adapt to a loss of visual information about the moving target object's position by sometimes successfully contacting the object in the barrier conditions. However, infants reached less often and with less success when access to, or sight of, the target object was obstructed. The infants' visual tracking, obstacle-avoidance skills, and ability to retain information about a hidden object were examined in conjunction with kinematic data to explain infants' limitations in adapting to obstacles in reaching tasks. These limitations involved difficulty visually tracking the object past a barrier, particularly in the dark conditions, as well as difficulty successfully aiming a reach around a barrier. Infants appeared to ignore the path of their hand on its way toward the target object, resulting in the hand frequently contacting a barrier rather than the target. Infants' successful contacts in the barrier conditions suggest that they do not require constant visual information about target position in order to enact a proficient reach. Further, infants appear to predict the reappearance of the target object and remember the path and speed of the object during its occlusion.
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Chen, Chao-Yeh. "Clues from the beaten path : location estimation with bursty sequences of tourist photos." Thesis, 2010. http://hdl.handle.net/2152/ETD-UT-2010-12-2301.
Full textAbstract:
Existing methods for image-based location estimation generally attempt to recognize every photo independently, and their resulting reliance on strong visual feature matches makes them most suited for distinctive landmark scenes. We observe that when touring a city, people tend to follow common travel patterns---for example, a stroll down Wall Street might be followed by a ferry ride, then a visit to the Statue of Liberty or Ellis Island museum. We propose an approach that learns these trends directly from online image data, and then leverages them within a Hidden Markov Model to robustly estimate locations for novel sequences of tourist photos. We further devise a set-to-set matching-based likelihood that treats each ``burst" of photos from the same camera as a single observation, thereby better accommodating images that may not contain particularly distinctive scenes. Our experiments with two large datasets of major tourist cities clearly demonstrate the approach's advantages over traditional methods that recognize each photo individually, as well as a naive HMM baseline that lacks the proposed burst-based observation model.text
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Ellis, Donald William. "The hidden hand and the fluid object : craft in three sites of representation." 2004. http://arrow.unisa.edu.au:8081/1959.8/24957.
Full textAbstract:
Craft's role in its traditional sites is changing. Using Actor-network theory the thesis explores this contention in three sites of craft representation, a craft organisation, a university craft workshop and a craft exhibition. It was found that although craft remained in the operations and practices of these sites it was transformed contextually to perform roles beyond the skills of the hand and the material limits of the object. The research, summed up as The Hidden Hand and the Fluid Object, is significant for craft organisation, craft education and museum administration. The thesis also expands the applications of Actor-network theory as a research tool beyond its roots in science.thesis (PhDEducation)--University of South Australia, 2004.
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Huang, Ching-Kuo, and 黃清國. "Object-Oriented Design for a GUI System of Polyhedron Hidden-Line/Surface Removal and the Implementation in MFC." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/53513097113861982787.
Full textAbstract:
碩士國立雲林科技大學
機械工程系碩士班
89
Computer-Aided Design and Manufacturing has been extensively applied in almost every branch of modern industries. And solid modeling system has gradually become the mainstream in the area of Computer-Aided Design because of its ease use, conformance to the intuition of human nature, as well as complete data description. However, three-dimensional object displayed on the computer screen with hidden-lines visible, in most cases, produces ambiguous representations and complicates the visual comprehension. Therefore, the removal of hidden-line and hidden-surface is a prerequisite step in developing a solid modeling system. The purpose of this study is not only to employ the technique of object-oriented modeling in designing a GUI system and the algorithm for the removal of polyhedron hidden-line/surface but also to fulfill its implementation in the framework of MFC. This thesis can be divided into two major parts --- Design and Implementation. In the design aspect, referring to the existing theory of hidden-line/surface removal along with the theory of solid modeling, we develop a basic, general, reusable, and expandable class architecture based on the concepts of abstraction, encapsulation, inheritance, and polymorphism, etc. the essential elements of the object model. In the implementation aspect, we establish a simplified CAD software program system within the framework of MFC to demonstrate the capability of polyhedron hidden-line/surface removal. In addition, we also develop an interactive user interface that allows the user to view a 3D object in any orientation by simply moving the mouse and displays the appropriate hidden-line/surface removal picture in real-time. This real-time capability of hidden-line/surface removal also allows us to scrutinize the changing states of hidden-line/surface from orientation to orientation as well as to verify their correctness.