Thèses : « Interets points »

1

Loiseau-Witon, Nicolas. « Détection et description de points clés par apprentissage ». Electronic Thesis or Diss., Lyon, INSA, 2023. http://www.theses.fr/2023ISAL0101.

Texte intégral

Résumé :

Les hôpitaux génèrent de plus en plus d’images médicales en 3D. Ces volumes nécessitent un recalage automatique, en vue d’être analysés de manière systématique et à grande échelle. Les points clés sont utilisés pour réduire la durée et la mémoire nécessaires à ce recalage et peuvent être détectés et décrits à l’aide de différentes méthodes classiques, mais également à l’aide de réseaux neuronaux, comme cela a été démontré de nombreuses fois en 2D. Cette thèse présente les résultats et les discussions sur les méthodes de détection et de description de points clés à l’aide de réseaux neuronaux 3D. Deux types de réseaux ont été étudiés pour détecter et/ou décrire des points caractéristiques dans des images médicales 3D. Les premiers réseaux étudiés permettent de décrire les zones entourant directement les points clés, tandis que les seconds effectuent les deux étapes de détection et de description des points clés en une seule fois
Hospitals are increasingly generating 3D medical images that require automatic registration for systematic and large-scale analysis. Key points are used to reduce the time and memory required for this registration, and can be detected and described using various classical methods, as well as neural networks, as demonstrated numerous times in 2D. This thesis presents results and discussions on methods for detecting and describing key points using 3D neural networks. Two types of networks were studied to detect and/or describe characteristic points in 3D medical images. The first networks studied describe the areas directly surrounding key points, while the second type performs both detection and description of key points in a single step

Styles APA, Harvard, Vancouver, ISO, etc.

2

Olofsson, Erik, et Simon Edström. « Points-Of-Interest CollectionGame ». Thesis, Umeå universitet, Institutionen för datavetenskap, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-38374.

Texte intégral

Résumé :

Location-based services often include showing Points-Of-Interest on a map and rely on the availability of geo-contextual data. In Pervasive Games, the players' context can be integrated with the game. Games of this character can be used in order to motivate users to collect Points-Of-Interest. This report describes the process of developing a concept and a working Android prototype where the users can have fun while creating Points-Of-Interest. A concept was developed by following the Design Process as well studying existing games and applications. The main goal of the project was to produce a prototype that is considered enjoyable by the users. The result is an Android prototype where the players can create, check-in, sabotage and upgrade Points-Of-Interest. In order to evaluate the game's perceived enjoyability, the Player Enjoyment Model for Pervasive Games was used. According to the validation of the prototype with the Player Enjoyment Model along with the conclusions from studies of similar applications, the authors believe the game has all the properties essential to an enjoyable game.

Styles APA, Harvard, Vancouver, ISO, etc.

3

Bayram, Ilker. « Interest Point Matching Across Arbitrary Views ». Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/12605114/index.pdf.

Texte intégral

Résumé :

Making a computer &lsquo
see&rsquo
is certainly one of the greatest challanges for today. Apart from possible applications, the solution may also shed light or at least give some idea on how, actually, the biological vision works. Many problems faced en route to successful algorithms require finding corresponding tokens in different views, which is termed the correspondence problem. For instance, given two images of the same scene from different views, if the camera positions and their internal parameters are known, it is possible to obtain the 3-Dimensional coordinates of a point in space, relative to the cameras, if the same point may be located in both images. Interestingly, the camera positions and internal parameters may be extracted solely from the images if a sufficient number of corresponding tokens can be found. In this sense, two subproblems, as the choice of the tokens and how to match these tokens, are examined. Due to the arbitrariness of the image pairs, invariant schemes for extracting and matching interest points, which were taken as the tokens to be matched, are utilised. In order to appreciate the ideas of the mentioned schemes, topics as scale-space, rotational and affine invariants are introduced. The geometry of the problem is briefly reviewed and the epipolar constraint is imposed using statistical outlier rejection methods. Despite the satisfactory matching performance of simple correlation-based matching schemes on small-baseline pairs, the simulation results show the improvements when the mentioned invariants are used on the cases for which they are strictly necessary.

Styles APA, Harvard, Vancouver, ISO, etc.

4

Chavez, Aaron J. « A fast interest point detection algorithm ». Thesis, Manhattan, Kan. : Kansas State University, 2008. http://hdl.handle.net/2097/538.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

5

Chucre, Mirla Rafaela Rafael Braga. « K-nearest neighbors queries in time-dependent road networks : analyzing scenarios where points of interest move to the query point ». reponame:Repositório Institucional da UFC, 2015. http://www.repositorio.ufc.br/handle/riufc/23696.

Texte intégral

Résumé :

CHUCRE, Mirla Rafaela Rafael Braga. K-nearest neighbors queries in time-dependent road networks: analyzing scenarios where points of interest move to the query point. 2015. 65 f. Dissertação (Mestrado em Ciência da Computação)-Universidade Federal do Ceará, Fortaleza, 2015.
Submitted by Jonatas Martins (jonatasmartins@lia.ufc.br) on 2017-06-29T12:26:58Z No. of bitstreams: 1 2015_dis_mrrbchucre.pdf: 15845328 bytes, checksum: a2e4d0a03ca943372c92852d4bcf7236 (MD5)
Approved for entry into archive by Rocilda Sales (rocilda@ufc.br) on 2017-06-29T13:54:36Z (GMT) No. of bitstreams: 1 2015_dis_mrrbchucre.pdf: 15845328 bytes, checksum: a2e4d0a03ca943372c92852d4bcf7236 (MD5)
Made available in DSpace on 2017-06-29T13:54:36Z (GMT). No. of bitstreams: 1 2015_dis_mrrbchucre.pdf: 15845328 bytes, checksum: a2e4d0a03ca943372c92852d4bcf7236 (MD5) Previous issue date: 2015
A kNN query retrieve the k points of interest that are closest to the query point, where proximity is computed from the query point to the points of interest. Time-dependent road networks are represented as weighted graphs, where the weight of an edge depends on the time one passes through that edge. This way, we can model periodic congestions during rush hour and similar effects. Travel time on road networks heavily depends on the traffic and, typically, the time a moving object takes to traverse a segment depends on departure time. In time-dependent networks, a kNN query, called TD-kNN, returns the k points of interest with minimum travel-time from the query point. As a more concrete example, consider the following scenario. Imagine a tourist in Paris who is interested to visit the touristic attraction closest from him/her. Let us consider two points of interest in the city, the Eiffel Tower and the Cathedral of Notre Dame. He/she asks a query asking for the touristic attraction whose the path leading up to it is the fastest at that time, the answer depends on the departure time. For example, at 10h it takes 10 minutes to go to the Cathedral. It is the nearest attraction. Although, if he/she asks the same query at 22h, in the same spatial point, the nearest attraction is the Eiffel Tower. In this work, we identify a variation of nearest neighbors queries in time-dependent road networks that has wide applications and requires novel algorithms for processing. Differently from TD-kNN queries, we aim at minimizing the travel time from points of interest to the query point. With this approach, a cab company can find the nearest taxi in time to a passenger requesting transportation. More specifically, we address the following query: find the k points of interest (e.g. taxi drivers) which can move to the query point (e.g. a taxi user) in the minimum amount of time. Previous works have proposed solutions to answer kNN queries considering the time dependency of the network but not computing the proximity from the points of interest to the query point. We propose and discuss a solution to this type of query which are based on the previously proposed incremental network expansion and use the A∗ search algorithm equipped with suitable heuristic functions. We also discuss the design and correctness of our algorithm and present experimental results that show the efficiency and effectiveness of our solution.
Uma consulta de vizinhos mais próximos (ou kNN, do inglês k nearest neighbours) recupera o conjunto de k pontos de interesse que são mais próximos a um ponto de consulta, onde a proximidade é computada do ponto de consulta para cada ponto de interesse. Nas redes de rodovias tradicionais (estáticas) o custo de deslocamento de um ponto a outro é dado pela distância física entre esses dois pontos. Por outro lado, nas redes dependentes do tempo o custo de deslocamento (ou seja, o tempo de viagem) entre dois pontos varia de acordo com o instante de partida. Nessas redes, as consultas kNN são denominadas TD-kNN (do inglês Time-Dependent kNN). As redes de rodovias dependentes do tempo representam de forma mais adequada algumas situações reais, como, por exemplo, o deslocamento em grandes centros urbanos, onde o tempo para se deslocar de um ponto a outro durante os horários de pico, quando o tráfego é intenso e as ruas estão congestionadas, é muito maior do que em horários normais. Neste contexto, uma consulta típica consiste em descobrir os k restaurantes (pontos de interesse) mais próximos de um determinado cliente (ponto de consulta) caso este inicie o seu deslocamento ao meio dia. Nesta dissertação nós estudamos o problema de processar uma variação de consulta de vizinhos mais próximos em redes viárias dependentes do tempo. Diferentemente das consultas TD-kNN, onde a proximidade é calculada do ponto de consulta para um determinado ponto de interesse, estamos interessados em situações onde a proximidade deve ser calculada de um ponto de interesse para o ponto de consulta. Neste caso, uma consulta típica consiste em descobrir os k taxistas (pontos de interesse) mais próximos (ou seja, com o menor tempo de viagem) de um determinado cliente (ponto de consulta) caso eles iniciem o seu deslocamento até o referido cliente ao meio dia. Desta forma, nos cenários investigados nesta dissertação, são os pontos de interesse que se deslocam até o ponto de consulta, e não o contrário. O método proposto para executar este tipo de consulta aplica uma busca A∗ à medida que vai, de maneira incremental, explorando a rede. O objetivo do método é reduzir o percentual da rede avaliado na busca. A construção e a corretude do método são discutidas e são apresentados resultados experimentais com dados reais e sintéticos que mostram a eficiência da solução proposta.

Styles APA, Harvard, Vancouver, ISO, etc.

6

Van, Niekerk A., et M. Conradie. « Literary genres as points of interest in print advertising ». Journal for New Generation Sciences, Vol 12, Issue 2 : Central University of Technology, Free State, Bloemfontein, 2014. http://hdl.handle.net/11462/665.

Texte intégral

Résumé :

Published Article
The article focuses on the interplay between print advertisements and literary genres such as poetry, drama, folklore, etc. This interplay may be used to develop an advertisement's point of interest to attract attention from a specific target audience. Based on previous research we hypothesise that literary genres are exploited as a means to engage audiences. The study aims to give a description of the typical genre characteristics of modern literary genres in SA print advertising. It also endeavours to do a pragmatic analysis of these advertisements against the background of the specific literary genre category and the genre qualities of advertisements to identify the implied marketing message.

Styles APA, Harvard, Vancouver, ISO, etc.

7

Bachert, Sara-Lois. « Points of Interest : Essays on People, Places and Perceptions ». TopSCHOLAR®, 1989. http://digitalcommons.wku.edu/theses/1873.

Texte intégral

Résumé :

I wrote my first story in third grade. “Francine and the Head-Chopper Man” borrowed its plot from “Beauty and the Beast,” but my teacher didn’t seem to mind. In fact, she arranged for me to read the story to the fifth-grade class down the hall. After that first public reading, I was hooked. I knew at age seven I was going to be a writer. When I discovered journalism in the ninth grade, I knew just what type of writing I was going to do. In junior high and high school, I was editor of the newspapers, and in college I worked on the newspaper and was editor of the yearbook. After graduation I was a reporter, copy editor and features editor at two daily newspapers in Kentucky. I began teaching journalism part-time at Western Kentucky University in 1983, and two years later, when I heard about the English department’s new writing concentration, I decided to study for my master’s. In Frank Steele’s Advanced Writing Workshop, I was confronted by a question I hadn’t asked in years: What did I want to write? Having written newspaper articles for years, I wanted to try something different – the essay, based on fact and usually written in the first person, although not necessarily. I believe this type of writing is valuable because it records and attempts to understand events, people and perceptions. As the number of essays grew, I began to realize a potential problem: If the subjects are dissimilar, any collection of essays runs the risk of seeming disorganized. If the subjects are similar, it runs the risk of sounding the same from essay to essay. I hope this collection of essays avoids both faults. The subjects are dissimilar – ranging from family to education – but revolve around the common themes of relationships and time. Each essay examines relationships between parents and children, sisters and brothers, friends, teachers and students, or others. In addition, they all deal with time, either chronicling the passage of time or preserving the moment. Most of the essays are written in the first person, and many deal with family issues. Those two details may sound as if the collection is germane to only one person, the writer. But it is not. Most readers will recognize themselves or people they know in the characters, and many will recall a way of life, an attitude, or a conversation they thought they had forgotten. Even those who don’t recognize or remember the characters may find the essays valuable if they learn a little about ordinary people and ordinary problems.

Styles APA, Harvard, Vancouver, ISO, etc.

8

Piekenbrock, Matthew J. « Discovering Intrinsic Points of Interest from Spatial Trajectory Data Sources ». Wright State University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=wright1527160689990512.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

9

Alghamdi, Hamzah. « E-Tourism : Context-Aware Points of Interest Finder and Trip Designer ». Thesis, Université d'Ottawa / University of Ottawa, 2017. http://hdl.handle.net/10393/35676.

Texte intégral

Résumé :

Many countries depend heavily on tourism for their economic growth. The invention of the web has opened new opportunities for tourists to discover new places and live new adventures. However, the number of possible destinations has become huge and even an entire lifespan would not be enough to visit all of these places. Even for one city, there are a significant number of possible places to visit. Nowadays, searching online to find an interesting place to visit is harder than ever, not because there is a lack of information but rather due to the vast amount of information that can be found. Trip planning is a tedious task, especially when the tourist does not want to pick a preplanned itinerary from a traveling agency. That being said, even these preplanned itineraries need a lot of time and effort to be customized. Moreover, the set of itineraries that a tourist can select from is usually limited. In addition, there may be many places that tourists would enjoy visiting but that are not included in the itineraries. Thus, static planners do not always choose the right place at the right time. This is why the planning process should take into consideration many factors in order to give the tourist the best possible suggestions. In this Thesis, we propose an algorithm called the Balanced Orienteering Problem to design trips for tourists. This algorithm, combined with a context-aware recommender system for tourism suggestions, create the infrastructure of the mobile application for the augmented reality tourism guide that we developed. We cover the background knowledge of tour planning problems and tourism recommender systems and describe the existing techniques. Furthermore, a comparison between the existing systems and our algorithm is completed to illustrate that our proposed algorithm yields better results. We also discuss the workflow of our system implementation and how our mobile application is designed. Lastly, we address suggestions for future works and end with a conclusion.

Styles APA, Harvard, Vancouver, ISO, etc.

10

Hodzic, Lana. « TRPINav : A System for Terrain, Route, Points of Interest, and Navigation ». DigitalCommons@CalPoly, 2016. https://digitalcommons.calpoly.edu/theses/1589.

Texte intégral

Résumé :

Maps are as fundamental to society as language and the written word. Maps are an abstraction of reality that help people to better understand the world around them. Route maps, specifically, depict a path from one place to another. Many route maps generated today contain excessive information making it difficult for people to process visually. Previous work has been done in generating routes, searching for nearby points of interest, and path generalization. This thesis proposes a system, TRPINav, that will integrate terrain data, route data, points of interest, and navigation in a cartographic visualization. This prototype navigation application includes a system designed to unify data from various sources, such as Yelp, Google Maps, and Digital Elevation Models (DEMs) into a single coordinate frame for useful navigation and reference. This system presents a model to handle data acquisition and unification of these data sources and render them in a simplified and pleasing representation to the user. The prototype includes simple rendering techniques and a user study to validate which features are appealing and useful to the user. Analysis shows that users are generally pleased with features of the system, and that the system can help answer some geographic questions. The results of this analysis are used to determine future iterations of the system.

Styles APA, Harvard, Vancouver, ISO, etc.

11

Bai, Xueyao. « Distributed Visual Processing Based On interest Point Clustering ». Thesis, KTH, Kommunikationsnät, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-168013.

Texte intégral

Résumé :

In this master thesis project, we study the problem in Visual Sensor Networks in which only limited bandwidth is provided. The task is to search for ways to decrease the transmitting data on the camera side, and distribute the data to dif- ferent nodes. To do so, we extract the interest points on the camera side by using BRISK in- terest point detector, and we distribute the detected interest points into di erent number of processing node by implementing proposed clustering methods, namely, Number Based Clustering, K-Means Clustering and DBSCAN Clustering. Our results show it is useful to extract interest points on the camera side, which can reduce almost three quarters of data in the network. A step further, by imple- menting the clustering algorithms, we obtained the gain in overhead ratio, interest point imbalance and pixel processing load imbalance, respectively. Specically, the results show that none of the proposed clustering methods is better than oth- ers. Number Based Clustering can balance the processing load between di erent processing nodes perfectly, but performs bad in saving the bandwidth resources. K-Means Clustering performs middle in the evaluation while DBSCAN is great in saving the bandwidth resources but leads to a bad processing balance performance among the processing nodes.

Styles APA, Harvard, Vancouver, ISO, etc.

12

Braga, Reinaldo. « LIDU : Location-based approach to IDentify similar interests between Users in social networks ». Thesis, Grenoble, 2012. http://www.theses.fr/2012GRENM055/document.

Texte intégral

Résumé :

Grâce aux technologies web et mobiles, le partage de données entre utilisateurs a considérablement augmenté au cours des dernières années. Par exemple, les utilisateurs peuvent facilement enregistrer leurs trajectoires durant leurs déplacements quotidiens avec l'utilisation de récepteurs GPS et les mettre en relation avec les trajectoires d'autres utilisateurs. L'analyse des trajectoires des utilisateurs au fil du temps peut révéler des habitudes et préférences. Cette information peut être utilisée pour recommander des contenus à des utilisateurs individuels ou à des groupes d'utilisateurs avec des trajectoires ou préférences similaires. En revanche, l'enregistrement de points GPS génère de grandes quantités de données. Par conséquent, les algorithmes de clustering sont nécessaires pour analyser efficacement ces données. Dans cette thèse, nous nous concentrons sur l'étude des différentes solutions pour analyser les trajectoires, extraire les préférences et identifier les intérêts similaires entre les utilisateurs. Nous proposons un algorithme de clustering de trajectoires GPS. En outre, nous proposons un algorithme de corrélation basée sur les trajectoires des points proches entre deux ou plusieurs utilisateurs. Les résultats finaux ouvrent des perspectives intéressantes pour explorer les applications des réseaux sociaux basés sur la localisation
Sharing of user data has substantially increased over the past few years facilitated by sophisticated Web and mobile applications, including social networks. For instance, users can easily register their trajectories over time based on their daily trips captured with GPS receivers as well as share and relate them with trajectories of other users. Analyzing user trajectories over time can reveal habits and preferences. This information can be used to recommend content to single users or to group users together based on similar trajectories and/or preferences. Recording GPS tracks generates very large amounts of data. Therefore clustering algorithms are required to efficiently analyze such data. In this thesis, we focus on investigating ways of efficiently analyzing user trajectories, extracting user preferences from them and identifying similar interests between users. We demonstrate an algorithm for clustering user GPS trajectories. In addition, we propose an algorithm to correlate trajectories based on near points between two or more users. The final results provided interesting avenues for exploring Location-based Social Network (LBSN) applications

Styles APA, Harvard, Vancouver, ISO, etc.

13

McKeehan, Zachary D. « Vision-based interest point extraction evaluation in multiple environments ». Thesis, Monterey, Calif. : Naval Postgraduate School, 2008. http://edocs.nps.edu/npspubs/scholarly/theses/2008/Sept/08Sep%5FMcKeehan.pdf.

Texte intégral

Résumé :

Thesis (M.S. in Computer Science)--Naval Postgraduate School, September 2008.
Thesis Advisor(s): Kolsch, Mathias ; Squire, Kevin. "September 2008." Description based on title screen as viewed on November 3, 2008. Includes bibliographical references (p. 175-181). Also available in print.

Styles APA, Harvard, Vancouver, ISO, etc.

14

Faille, Flore. « Illumination invariant interest point detection for vision based recognition tasks ». [S.l.] : [s.n.], 2007. http://mediatum2.ub.tum.de/doc/613251/document.pdf.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

15

Jakobsson, Viktor. « The Förstner Interest Point Operator Subwindow Localization on SIFT Keypoints ». Thesis, Umeå universitet, Institutionen för fysik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-105492.

Texte intégral

Résumé :

This thesis suggests a modiﬁcation to the popular Scale Invariant Feature Transform (SIFT) algorithm (Lowe, 2004) often used in photogrammetry and computer vision to ﬁnd features in images for measurement. The SIFT algorithm works by ﬁrst detecting points in images at diﬀerent scales and sizes. It then reﬁnes the position of the found points. The algorithm creates a descriptor of the point based on the region around the point. Finally the points can be matched against other points in diﬀerent images using the descriptor. The suggested modiﬁcation is built upon a paper by Förstner and Gülch (1987) where a method for performing a subwindow localization is presented. In this thesis the keypoints detected by the SIFT algorithm are modiﬁed on the subwindow level in order to improve the robustness with respect to the selected window position. Several diﬀerent methods of tweaking the suggested modiﬁcation and the SIFT algorithm were tested. The methods were evaluated on two diﬀerent test cases. The ﬁrst used a camera calibration software to compare accuracy of keypoints by looking at the residuals of the calibration. The other test involved creating a point cloud of images of a planar surface, evaluating the results by looking at the standard deviation in keypointoﬀset from the plane.The results show that neither test gave evidence that the proposed modiﬁcation was an improvement. It was found that the algorithm had problems with oblique projections of circles, i.e. ellipses. Therefore there is potentialto use homography in special cases to circumvent this problem and get better precision. Furthermore tests involving more lines and intersections in the test images should be performed before this suggested modiﬁcationcan be completely discarded.

Styles APA, Harvard, Vancouver, ISO, etc.

16

Lindeberg, Tony. « Scale Selection Properties of Generalized Scale-Space Interest Point Detectors ». KTH, Beräkningsbiologi, CB, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-101220.

Texte intégral

Résumé :

Scale-invariant interest points have found several highly successful applications in computer vision, in particular for image-based matching and recognition. This paper presents a theoretical analysis of the scale selection properties of a generalized framework for detecting interest points from scale-space features presented in Lindeberg (Int. J. Comput. Vis. 2010, under revision) and comprising: an enriched set of differential interest operators at a fixed scale including the Laplacian operator, the determinant of the Hessian, the new Hessian feature strength measures I and II and the rescaled level curve curvature operator, as well as an enriched set of scale selection mechanisms including scale selection based on local extrema over scale, complementary post-smoothing after the computation of non-linear differential invariants and scale selection based on weighted averaging of scale values along feature trajectories over scale. A theoretical analysis of the sensitivity to affine image deformations is presented, and it is shown that the scale estimates obtained from the determinant of the Hessian operator are affine covariant for an anisotropic Gaussian blob model. Among the other purely second-order operators, the Hessian feature strength measure I has the lowest sensitivity to non-uniform scaling transformations, followed by the Laplacian operator and the Hessian feature strength measure II. The predictions from this theoretical analysis agree with experimental results of the repeatability properties of the different interest point detectors under affine and perspective transformations of real image data. A number of less complete results are derived for the level curve curvature operator.

QC 20121003

Image descriptors and scale-space theory for spatial and spatio-temporal recognition

Styles APA, Harvard, Vancouver, ISO, etc.

17

Akbarzadeh, Kasra. « Navigational aid to points of interests outside the field of view in virtual environments ». Thesis, Luleå tekniska universitet, Institutionen för system- och rymdteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-73221.

Texte intégral

Résumé :

Advances in Virtual reality have brought opportunities for cinematic content to the users by allowing them to look around freely in any arbitrary direction and to interact as they please. This, however, imposes difficulties to the content creators as the freedom given to the audience results in less control over the user. The lack of control over what the audience is paying attention to could cause them to miss out on important points of interests and content creators can no longer rely on previous methods to draw and direct their attention. This study aims to find different means in how to direct and draw the attention of participants inside a 3-dimensional virtual environment without disrupting the virtual experience. This is achieved by comparing five different approaches in the virtual environment to navigate the participants. These approaches are Flicker, Dim, Auditory feedback, Haptic feedback and Tilt. A total of 15 participants participated in this study and were, post simulation, given a questionnaire to evaluate which approach was the least obvious, confusing and disturbing. One approach, flicker, had the best outcome in terms of guiding the participants in the virtual environment but was perceived to be the most disturbing one as well.

Styles APA, Harvard, Vancouver, ISO, etc.

18

Jaber, Maher, et Andrei Cojanu. « The 40 Seconds Rule and Points of Interest in The Witcher 3 : Wild Hunt ». Thesis, Uppsala universitet, Institutionen för speldesign, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-446386.

Texte intégral

Résumé :

The Witcher 3: Wild Hunt is one of the best selling open world video games in recent years. Thanks to the game’s popularity, other game designers might want to replicate its world design methods. In an interview from 2017, the game’s developers have explained that they have used a system called “the rule of 40 seconds” to ensure that the player stumbles upon something interesting every 40 seconds of exploration. In this research, the authors conducted a test to check how accurately the rule was implemented; they did this by analysing footage of gameplay from four different YouTube content creators, on two of the game’s maps. The research found that a Rule does exist, however, it is greatly influenced by playstyles and only accurate for certain players. It concludes that designers looking to implement the rule, can reliably do so, but they should take playing styles and player movement speed into consideration when testing their rule.
The Witcher 3: Wild Hunt är ett av de bäst säljande öppna världsspel de senaste åren. Tack vare spelets popularitet kanske andra speldesigners vill kopiera dess värld designmetoder. I en intervju från 2017 har spelets utvecklare förklarat att de har använt ett system som kallas ”regeln om 40 sekunder” för att säkerställa att spelaren snubblar på något intressant var fjärde sekund av utforskningen. I denna forskning genomförde författarna ett test för att kontrollera hur korrekt regeln implementerades; de gjorde det genom att analysera bilder från fyra olika innehållsskapare på YouTube på två av spelets kartor. Forskningen visade att det finns en regel, men den påverkas av spelstilar och är endast korrekt för vissa spelare. Det drar slutsatsen att designers som vill implementera regeln kan göra det på ett tillförlitligt sätt, men de bör ta hänsyn till spelstilar och spelarens rörelsehastighet när de testar deras regel.

Styles APA, Harvard, Vancouver, ISO, etc.

19

Madsen, Michael H. Mosher Anne E. « Mormon meccas : the spiritual transformation of Mormon historical sites from points of interest to sacred space ». Related Electronic Resource : Current Research at SU : database of SU dissertations, recent titles available full text, 2003. http://wwwlib.umi.com/cr/syr/main.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

20

Tran, Khoa Anh. « Automatic Identification of Points of Interest in Global Navigation Satellite System Data : A Spatial Temporal Approach ». Scholar Commons, 2013. http://scholarcommons.usf.edu/etd/4595.

Texte intégral

Résumé :

In addition to the emergence of smartphones and tablets in recent years, the rise of Global Navigation Satellite Systems (GNSS) has allowed mobile tracking applications to become popular and be put into many uses. Analyzing tracking records to identify points of interest (POIs) is useful for both prediction applications and research such as human behavior analysis, transportation planning, and especially travel surveys. Past research in travel surveys has shown that a GPS mobile phone-based survey is a useful tool for collecting information about individuals. Moreover, a passive travel survey collection is preferred to an active travel survey method by the respondents and the analysts because it is proven to be less error prone. However, passive collection remains a challenge due to a lack of high accuracy algorithms to automatically identify trip starts and trip ends. While travel surveys need a POI identification algorithm to carry out passive information collection, mobile tracking applications must be careful not to affect the user's battery life, which limits the number of GPS coordinates that can be recorded and therefore affects the accuracies of existing POI identification algorithms. This thesis presents Automatic Spatial Temporal Identification of Points of Interest (ASTIPI), an unsupervised spatial temporal algorithm to identify POIs. ASTIPI utilizes the temporal and spatial properties of the dataset to obtain a high accuracy of POI identification, even on a reduced GPS dataset that uses techniques to conserve battery life on mobile devices. While reducing outliers within POIs, ASTIPI also has a linear running time and maintains the temporal orders of the location data so that arrival and departure information can be easily extracted and thus, users' trips can be quickly identified. Using data from real mobile devices, evaluations of ASTIPI and other existing algorithms are performed, showing that ASTIPI obtains the highest accuracy of POI identification with an average accuracy of 88% when performing on full datasets generated using the GPS Auto-Sleep module and an average accuracy of 59% when performing on a reduced dataset generated using both the GPS Auto-Sleep module and the Critical Points algorithm.

Styles APA, Harvard, Vancouver, ISO, etc.

21

Palomares, Jean-Louis. « Une nouvelle méthode d’appariement de points d’intérêt pour la mise en correspondance d’images ». Thesis, Montpellier 2, 2012. http://www.theses.fr/2012MON20075/document.

Texte intégral

Résumé :

Ce mémoire de thèse traite de la mise en correspondance d'images pour des applications de vision stéréoscopique ou de stabilisation d'images de caméras vidéo. les méthodes de mise en correspondance reposent généralement sur l'utilisation de points d'intérêts dans les images, c'est-à-dire de points qui présentent de fortes discontinuités d'intensité lumineuse. Nous présentons tout d'abord un nouveau descripteur de points d'intérêt, obtenu au moyen d'un filtre anisotropique rotatif qui délivre en chaque point d'intérêt une signature mono-dimensionnelle basée sur un gradient d'intensité. Invariant à la rotationpar construction, ce descripteur possède de trés bonnes propriétés de robustesse et de discrimination. Nous proposons ensuite une nouvelle méthode d'appariement invariante aux transformations euclidiennes et affines. Cette méthode exploite la corrélation des signatures sous l'hypothèse de faibles déformations, et définit une mesure de distance nécessaire à l'appariement de points. Les résultats obtenus sur des images difficiles laissent envisager des prolongements prometteurs de cette méthode
This thesis adresses the issue of image matching for stereoscopic vison applications and image stabilization of video cameras. Methods of mapping are generally based on the use of interest points in the images, i.e. of points which have strong discontinuities in light intensity. We first present a new descriptor of points of interest, obtained by means of an anisotropic rotary filter which delivers at each point of interest a one-dimensional signature based on an intensity gradient. Invariant to rotation by construction, thisdescriptor has very good properties of robustness and discrimination. We then propose a new matching method invariant to Euclidean and affine transformations. This method exploits the correlation of the signatures subject to moderate warping, and defines a distance measure, necesssary for the matching of points. the results obtained on difficult images augur promising extentions to this method

Styles APA, Harvard, Vancouver, ISO, etc.

22

LOZET, POUYMAYOU CATHERINE. « Histiocytose a cellules de langerhans : mise au point et interet diagnostique de l'immunophenotypage ». Aix-Marseille 2, 1992. http://www.theses.fr/1992AIX20904.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

23

Hotze, Wolfgang. « Robotic First Aid : Using a mobile robot to localise and visualise points of interest for first aid ». Thesis, Högskolan i Halmstad, Akademin för informationsteknologi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-32324.

Texte intégral

Résumé :

Domestic robots developed to support human beings by performing daily tasks such as cleaning should also be able to help in emergencies by finding, analysing, and assisting persons in need of first aid. Here such a robot capable of performing some useful task related to first aid is referred to as a First Aid Mobile Robot (FAMR). One challenge which to the author's knowledge has not been solved is how such a FAMR can find a fallen person's pose within an environment, recognising locations of points of interest for first aid such as the mouth, nose, chin, chest and hands on a map. To overcome the challenge, a new approach is introduced based on leveraging a robot's capabilities (multiple sensors and mobility), called AHBL. AHBL comprises four steps: Anomaly detection, Human detection, Body part recognition, and Localisation on a map. It was broken down into four steps for modularity (e.g., a different way of detecting anomalies can be slipped in without changing the other modules) and because it was not clear which step is hardest to implement. As a result of evaluating AHBL, a FAMR developed for this work was able to find the pose of a fallen person (a mannequin) in a known environment with an average success rate of 83%, and an average localisation discrepancy of 1.47cm between estimated body part locations and ground truth. The presented approach can be adapted for use in other robots and contexts, and can act as a starting point toward designing systems for autonomous robotic first aid.

Styles APA, Harvard, Vancouver, ISO, etc.

24

Brilhante, Igo Ramalho. « Mobility Data under Analysis a Complex Network Perspective from Interactions Among Trajectories to Movements among Points Interest ». reponame:Repositório Institucional da UFC, 2012. http://www.repositorio.ufc.br/handle/riufc/18792.

Texte intégral

Résumé :

BRILHANTE, Igo Ramalho. Mobility Data under Analysis a Complex Network Perspective from Interactions Among Trajectories to Movements among Points Interest. 2012. 104 f. Dissertação (Mestrado em ciência da computação)- Universidade Federal do Ceará, Fortaleza-CE, 2012.
Submitted by Elineudson Ribeiro (elineudsonr@gmail.com) on 2016-07-28T19:53:04Z No. of bitstreams: 1 2012_dis_irbrilhante.pdf: 13581729 bytes, checksum: 9b1d7b6164309bf59f7d6ba1370cd90e (MD5)
Approved for entry into archive by José Jairo Viana de Sousa (jairo@ufc.br) on 2016-08-02T14:18:14Z (GMT) No. of bitstreams: 1 2012_dis_irbrilhante.pdf: 13581729 bytes, checksum: 9b1d7b6164309bf59f7d6ba1370cd90e (MD5)
Made available in DSpace on 2016-08-02T14:18:14Z (GMT). No. of bitstreams: 1 2012_dis_irbrilhante.pdf: 13581729 bytes, checksum: 9b1d7b6164309bf59f7d6ba1370cd90e (MD5) Previous issue date: 2012
The explosion of personal positioning devices like GPS-enabled smartphones has enabled the collection and storage of a huge amount of positioning data in the form of trajectories. Thereby, trajectory data have brought many research challenges in the process of recovery, storage and knowledge discovery in mobility as well as new applications to support our society in mobility terms. Other research area that has been receiving great attention nowadays is the area of complex network or science of networks. Complex network is the first approach to model complex system that are present in the real world, such as economic markets, the Internet, World Wide Web and disease spreading to name a few. It has been applied in different field, like Computer Science, Biology and Physics. Therefore, complex networks have demonstrated a great potential to investigate the behavior of complex systems through their entities and the relationships that exist among them. The present dissertation, therefore, aims at exploiting approaches to analyze mobility data using a perspective of complex networks. The first exploited approach stands for the trajectories as the main entities of the networks connecting each other through a similarity function. The second, in turn, focuses on points of interest that are visited by people, which perform some activities in these points. In addition, this dissertation also exploits the proposed methodologies in order to develop a software tool to support users in mobility analysis using complex network techniques.
The explosion of personal positioning devices like GPS-enabled smartphones has enabled the collection and storage of a huge amount of positioning data in the form of trajectories. Thereby, trajectory data have brought many research challenges in the process of recovery, storage and knowledge discovery in mobility as well as new applications to support our society in mobility terms. Other research area that has been receiving great attention nowadays is the area of complex network or science of networks. Complex network is the first approach to model complex system that are present in the real world, such as economic markets, the Internet, World Wide Web and disease spreading to name a few. It has been applied in different field, like Computer Science, Biology and Physics. Therefore, complex networks have demonstrated a great potential to investigate the behavior of complex systems through their entities and the relationships that exist among them. The present dissertation, therefore, aims at exploiting approaches to analyze mobility data using a perspective of complex networks. The first exploited approach stands for the trajectories as the main entities of the networks connecting each other through a similarity function. The second, in turn, focuses on points of interest that are visited by people, which perform some activities in these points. In addition, this dissertation also exploits the proposed methodologies in order to develop a software tool to support users in mobility analysis using complex network techniques.

Styles APA, Harvard, Vancouver, ISO, etc.

25

Berjawi, Bilal. « Integration of heterogeneous data from multiple location-based services providers : A use case on tourist points of interest ». Thesis, Lyon, 2017. http://www.theses.fr/2017LYSEI072/document.

Texte intégral

Résumé :

Les fournisseurs de services géo-localisés (LBS) offrent des données textuelles et spatiales complémentaires, parfois incohérentes et imprécises, représentant les différents points d’intérêt (POI) sur un territoire donné. Ainsi, une même requête lancée auprès de divers fournisseurs de services touristiques peut donner des résultats différents et parfois incohérents, pour les attributs terminologiques et/ou les attributs spatiaux. De plus, chaque fournisseur utilise sa propre convention graphique pour représenter les POIs. L’intégration de ces données spatiales hétérogènes dans un contexte dynamique, large échelle, utilisant des sources incomplètes et de qualités variables est actuellement un verrou technologique. Dans ce travail de thèse, nous cherchons une solution à cette intégration aussi bien au niveau des données que de leur représentation
Location Based Services (LBS) had been involved to deliver relevant geospatial information based on a geographic position or address. The amount of geospatial data is constantly increasing, making it a valuable source of information for enriching LBS applications. However, these geospatial data are highly inconsistent and contradictory from one source to another. We assume that integrating geospatial data from several sources may improve the quality of information offered to users. In this thesis, we specifically focus on data representing Points of Interest (POIs) that tourists can get through LBS. Retrieving, matching and merging such geospatial entities lead to several challenges. We mainly focus on three main challenges including (i) detecting and merging corresponding entities across multiple sources and (ii) considering the uncertainty of integrated entities and their representation in LBS applications

Styles APA, Harvard, Vancouver, ISO, etc.

26

Jansson, David, et Viktoria Sjöbohm. « En maskininlärningsanalys av ursprunget till bostadsområdens attraktionskraft : En kvantitativ studie kring Points of Interest inverkan på bostadsområdens attraktionskraft ». Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-281309.

Texte intégral

Résumé :

Efterfrågan på bostadsrätter i Stockholm har under de senaste åren varit hög och priserna svänger ständigt. Idag är många överens om att ‘läget’ är en av de viktigaste parametrarna i värderingen av en bostadsrätt men vad ‘läget’ egentligen innebär är inte lika självklart. Denna studie har syftet att undersöka potentiella samband mellan ett läges attraktivitet och antal Points of Interest i en bostadsrätts närområde. Studien avser att besvara vilka parametrar som har stärst inverkan på ett bostadsområdes attraktionskraft. Points of Interest utgörs av bland annat postnummer, antal restauranger och antal hotell inom en kilometers radie från respektive bostadsrätt. Studiens utförande baseras på antagandet att försäljningspriser kan representera betalningsviljan och därigenom attraktionskraften. Utförandet baseras på maskininlärning, där modellen Random Forest Regression implementeras för att utföra en kvantitativ dataanalys på sålda bostadsrätter i Stockholm. Modellen kan estimera försäljningspris med en noggrannhet på 85,1% och resultatet redovisar Points of Interest påverkan på det estimerade försäljningspris, i förhållande till varandra. Den parameter som har störst inverkan på försäljningspriset var postnumret. Postnumret följs av kommunikationer och uteliv. Detta utfall diskuteras bero på att postnumret indirekt representerar icke-kvantitativa parametrar som allmän uppfattning om området. Kommunikationer och uteliv skapar ett ’levande’ område. Utifrån studiens resultat drogs slutsatsen att den största påverkande faktorn för ett läges attraktionskraft är den allmänna uppfattningen om närområdet, snarare än tillgänglighet till Points of Interest.
The demand on co-operative apartments in Stockholm have during the latest years been high and the prices are continuously fluctuating. Today, many agree on that the ‘location’ is one of the most important aspects in valuation of co-operative apartments but what ‘location’ actually means is not as obvious. This thesis has the purpose of exploring potential connections between a location’s attractiveness and the amount of Points of Interest in a co-operative apartment’s close proximity. The study seeks to explain which features that affects a community’s attractiveness the most. Points of Interest includes, among others, postal code, number of restaurants and number of hotels within a radius of one kilometer from each individual cooperative apartment. The study’s performance is based on the presumption that sales prices can represent willingness to pay and thereby represent attractiveness. The performance is based on machine learning, where the model Random Forest Regression is implemented to perform a quantitative data analysis on sold co-operative apartments in Stockholm. The model can estimate sales prices with an accuracy of 85.1% and the result presents the Points of Interests’ effect on the estimated sales prices, in relation to each other. The feature which was shown to have the highest effect on the estimated sales price was the postal code. It is discussed that this outcome is due to the postal code indirectly represent non-quantitative features such as the general perception of the area. The second and third most important features is showed to be public transport and nightlife. From the study it was concluded that the most important feature for the attractiveness of a location is the general perception of that area rather than the accessibility to Points of Interest.

Styles APA, Harvard, Vancouver, ISO, etc.

27

Emir, Erdem. « A Comparative Performance Evaluation Of Scale Invariant Interest Point Detectors For Infrared And Visual Images ». Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/2/12610159/index.pdf.

Texte intégral

Résumé :

In this thesis, the performance of four state-of-the-art feature detectors along with SIFT and SURF descriptors in matching object features of mid-wave infrared, long-wave infrared and visual-band images is evaluated across viewpoints and changing distance conditions. The utilized feature detectors are Scale Invariant Feature Transform (SIFT), multiscale Harris-Laplace, multiscale Hessian-Laplace and Speeded Up Robust Features (SURF) detectors, all of which are invariant to image scale and rotation. Features on different blackbodies, human face and vehicle images are extracted and performance of reliable matching is explored between different views of these objects each in their own category. All of these feature detectors provide good matching performance results in infrared-band images compared with visual-band images. The comparison of matching performance for mid-wave and long-wave infrared images is also explored in this study and it is observed that long-wave infrared images provide good matching performance for objects at lower temperatures, whereas mid-wave infrared-band images provide good matching performance for objects at higher temperatures. The matching performance of SURF detector and descriptor for human face images in long-wave infrared-band is found to be outperforming than other detectors and descriptors.

Styles APA, Harvard, Vancouver, ISO, etc.

28

Bingham, Mark. « An interest point based illumination condition matching approach to photometric registration within augmented reality worlds ». Thesis, University of Huddersfield, 2011. http://eprints.hud.ac.uk/id/eprint/11048/.

Texte intégral

Résumé :

With recent and continued increases in computing power, and advances in the field of computer graphics, realistic augmented reality environments can now offer inexpensive and powerful solutions in a whole range of training, simulation and leisure applications. One key challenge to maintaining convincing augmentation, and therefore user immersion, is ensuring consistent illumination conditions between virtual and real environments, so that objects appear to be lit by the same light sources. This research demonstrates how real world lighting conditions can be determined from the two-dimensional view of the user. Virtual objects can then be illuminated and virtual shadows cast using these conditions. This new technique uses pairs of interest points from real objects and the shadows that they cast, viewed from a binocular perspective, to determine the position of the illuminant. This research has been initially focused on single point light sources in order to show the potential of the technique and has investigated the relationships between the many parameters of the vision system. Optimal conditions have been discovered by mapping the results of experimentally varying parameters such as FoV, camera angle and pose, image resolution, aspect ratio and illuminant distance. The technique is able to provide increased robustness where greater resolution imagery is used. Under optimal conditions it is possible to derive the position of a real world light source with low average error. An investigation of available literature has revealed that other techniques can be inflexible, slow, or disrupt scene realism. This technique is able to locate and track a moving illuminant within an unconstrained, dynamic world without the use of artificial calibration objects that would disrupt scene realism. The technique operates in real-time as the new algorithms are of low computational complexity. This allows high framerates to be maintained within augmented reality applications. Illuminant updates occur several times a second on an average to high end desktop computer. Future work will investigate the automatic identification and selection of pairs of interest points and the exploration of global illuminant conditions. The latter will include an analysis of more complex scenes and the consideration of multiple and varied light sources.

Styles APA, Harvard, Vancouver, ISO, etc.

29

Ahmad, Mohammad Zubair. « Measuring the evolving Internet ecosystem with exchange points ». Doctoral diss., University of Central Florida, 2013. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5753.

Texte intégral

Résumé :

The Internet ecosystem comprising of thousands of Autonomous Systems (ASes) now include Internet eXchange Points (IXPs) as another critical component in the infrastructure. Peering plays a significant part in driving the economic growth of ASes and is contributing to a variety of structural changes in the Internet. IXPs are a primary component of this peering ecosystem and are playing an increasing role not only in the topology evolution of the Internet but also inter-domain path routing. In this dissertation we study and analyze the overall affects of peering and IXP infrastructure on the Internet. We observe IXP peering is enabling a quicker flattening of the Internet topology and leading to over-utilization of popular inter-AS links. Indiscriminate peering at these locations is leading to higher end-to-end path latencies for ASes peering at an exchange point, an effect magnified at the most popular worldwide IXPs. We first study the effects of recently discovered IXP links on the inter-AS routes using graph based approaches and find that it points towards the changing and flattening landscape in the evolution of the Internet's topology. We then study more IXP effects by using measurements to investigate the networks benefits of peering. We propose and implement a measurement framework which identifies default paths through IXPs and compares them with alternate paths isolating the IXP hop. Our system is running and recording default and alternate path latencies and made publicly available. We model the probability of an alternate path performing better than a default path through an IXP by identifying the underlying factors influencing the end-to end path latency. Our first-of-its-kind modeling study, which uses a combination of statistical and machine learning approaches, shows that path latencies depend on the popularity of the particular IXP, the size of the provider ASes of the networks peering at common locations and the relative position of the IXP hop along the path. An in-depth comparison of end-to-end path latencies reveal a significant percentage of alternate paths outperforming the default route through an IXP. This characteristic of higher path latencies is magnified in the popular continental exchanges as measured by us in a case study looking at the largest regional IXPs. We continue by studying another effect of peering which has numerous applications in overlay routing, Triangle Inequality Violations (TIVs). These TIVs in the Internet delay space are created due to peering and we compare their essential characteristics with overlay paths such as detour routes. They are identified and analyzed from existing measurement datasets but on a scale not carried out earlier. This implementation exhibits the effectiveness of GPUs in analyzing big data sets while the TIVs studied show that the a set of common inter-AS links create these TIVs. This result provides a new insight about the development of TIVs by analyzing a very large data set using GPGPUs. Overall our work presents numerous insights into the inner workings of the Internet's peering ecosystem. Our measurements show the effects of exchange points on the evolving Internet and exhibits their importance to Internet routing.
Ph.D.
Doctorate
Electrical Engineering and Computing
Engineering and Computer Science
Computer Engineering

Styles APA, Harvard, Vancouver, ISO, etc.

30

Griesner, Jean-Benoit. « Systèmes de recommandation de POI à large échelle ». Electronic Thesis or Diss., Paris, ENST, 2018. http://www.theses.fr/2018ENST0037.

Texte intégral

Résumé :

La recommandation de points d’intérêts (POI) est une composante essentielle des réseaux sociaux géolocalisés. Cette tâche pose de nouveaux défis dûs aux contraintes spécifiques de ces réseaux. Cette thèse étudie de nouvelles solutions au problème de la recommandation personnalisée de POI. Trois contributions sont proposées dans ce travail. La première contribution est un nouveau modèle de factorisation de matrices qui intègre les influences géographique et temporelle. Ce modèle s’appuie sur un traitement spécifique des données. La deuxième contribution est une nouvelle solution au problème dit du feedback implicite. Ce problème correspond à la difficulté à distinguer parmi les POI non visités, les POI dont l’utilisateur ignore l’existence des POI qui ne l’intéressent pas. Enfin la troisième contribution de cette thèse est une méthode pour générer des recommandations à large échelle. Cette approche combine un algorithme de clustering géographique avec l’influence sociale des utilisateurs à différentes échelles de mobilité
The task of points-of-interest (POI) recommendations has become an essential feature in location-based social networks. However it remains a challenging problem because of specific constraints of these networks. In this thesis I investigate new approaches to solve the personalized POI recommendation problem. Three main contributions are proposed in this work. The first contribution is a new matrix factorization model that integrates geographical and temporal influences. This model is based on a specific processing of geographical data. The second contribution is an innovative solution against the implicit feedback problem. This problem corresponds to the difficulty to distinguish among unvisited POI the actual "unknown" from the "negative" ones. Finally the third contribution of this thesis is a new method to generate recommendations with large-scale datasets. In this approach I propose to combine a new geographical clustering algorithm with users’ implicit social influences in order to define local and global mobility scales

Styles APA, Harvard, Vancouver, ISO, etc.

31

LACERDA, Yuri Almeida. « Explorando a localização e orientação de fotograﬁas pessoais para descoberta de pontos de interesse baseada em agrupamento ». Universidade Federal de Campina Grande, 2017. http://dspace.sti.ufcg.edu.br:8080/jspui/handle/riufcg/703.

Texte intégral

Résumé :

Submitted by Kilvya Braga (kilvyabraga@hotmail.com) on 2018-05-16T14:43:46Z No. of bitstreams: 1 YURI ALMEIDA LACERDA - TESE (PPGCC) 2017.pdf: 28353805 bytes, checksum: 0d8453f39b64823b7308c81cc7731524 (MD5)
Made available in DSpace on 2018-05-16T14:43:46Z (GMT). No. of bitstreams: 1 YURI ALMEIDA LACERDA - TESE (PPGCC) 2017.pdf: 28353805 bytes, checksum: 0d8453f39b64823b7308c81cc7731524 (MD5) Previous issue date: 2017
Capes
A descoberta de conhecimento a partir de grandes repositórios online de fotograﬁas tem sido uma área de pesquisa bastante ativa nos últimos anos. Isso se deve principalmente a três fatores: incorporação de câmeras digitais e sensores de geolocalização aos dispositivos móveis; avanços na conectividade com a Internet; e evolução das redes sociais. As fotograﬁas armazenadas nesses repositórios possuem metadados contextuais que podem ser utilizados em aplicações de descoberta de conhecimento, tais como: detecção de pontos de interesse (POIs); geração de roteiros de viagens; e organização automática de fotograﬁas. A maioria das abordagens para detecção de POIs parte do princípio que as áreas geográﬁcas onde uma grande quantidade de pessoas capturou fotograﬁas indica a existência de um ponto de interesse. Porém, em muitos casos, os POIs estão localizados a uma certa distância desse local na orientação em que a câmera estava direcionada, e não no ponto exato da captura da fotograﬁa. A maioria das técnicas propostas na literatura não consideram o uso da orientação no processo de detecção de pontos de interesses. Dessa forma, este trabalho propõe novos algoritmos e técnicas para detecção de pontos de interesse em cidades turísticas a partir de coleções de fotograﬁas orientadas e georreferenciadas explorando de diversas formas a orientação geográﬁca. Esta pesquisa comprovou a importância do uso da orientação nos novos algoritmos voltados para detecção de pontos de interesses. Os experimentos, utilizando uma base de dados real de grandes cidades, demonstraram que os algoritmos considerando a orientação conseguem, em alguns cenários, superar os que não a consideram. Também foram propostas novas métricas de avaliação e uma ferramenta para auxiliar as atividades de descoberta de conhecimento baseada em grandes massas de fotograﬁas.
The knowledge discovery from huge photo repositories has been a very active area of research in the last years. This is due to three facts: the incorporation of digital cameras and geolocation sensors in mobile devices; the advances in Internet connectivity; and the evolution of social networks. The photos stored on those repositories have contextual metadata. Those metadata could be used for many applications of knowledge discovering, such as: Point of Interest (POI) detection; generating of tourist guides; and automatic photo organization. Most approaches for POI detection assume that geographic areas with high density of photos indicate the existence of a point of interest in that area. However, in many cases, the POIs are located in a certain distance of that position in direction where camera was aiming, and not in the exact point of photo shooting. Most of related work do not consider the use of orientation in the process of POI detection. In this way, we propose a set of algorithms and techniques for POI discovery in touristic cities using geotagged and oriented photos collection exploring the geographic orientation in different ways. This research has proven the importance of the usage of orientation in the new algorithms for POI detection. In the experiments with collections related to big cities, the algorithms considering orientation, in several scenarios, have beaten those that do not consider. Also, new metrics of evaluation have been proposed and a new framework to assist all the tasks for knowledge discovery based on huge photo collections.

Styles APA, Harvard, Vancouver, ISO, etc.

32

Murphy, Timothy Charles. « Examining the Effects of Key Point Detector and Descriptors on 3D Visual SLAM ». Ohio University Honors Tutorial College / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ouhonors1461320700.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

33

Johansson, Johan. « Interest Point Detectors and Descriptors for IR Images : An Evaluation of Common Detectors and Descriptors on IR images ». Thesis, KTH, Skolan för datavetenskap och kommunikation (CSC), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-175801.

Texte intégral

Résumé :

Interest point detectors and descriptors are the basis of many applications within computer vision. In the selection of which methods to use in an application, it is of great interest to know their performance against possible changes to the appearance of the content in an image. Many studies have been completed in the field on visual images while the performance on infrared images is not as charted. This degree project, conducted at FLIR Systems, provides a performance evaluation of detectors and descriptors on infrared images. Three evaluations steps are performed. The first evaluates the performance of detectors; the second descriptors; and the third combinations of detectors and descriptors. We find that best performance is obtained by Hessian-Affine with LIOP and the binary combination of ORB detector and BRISK descriptor to be a good alternative with comparable results but with increased computational efficiency by two orders of magnitude.
Detektorer och deskriptorer är grundpelare till många applikationer inom datorseende. Vid valet av metod till en specifik tillämpning är det av stort intresse att veta hur de presterar mot möjliga förändringar i hur innehållet i en bild framträder. Grundlig forskning är utförd på visuella bilder medan det fortfarande saknas en lika grundläggande kartläggning av deras prestation på infraröda bilder. Det här examensarbetet utvärderar, på uppdrag av FLIR Systems, hur detektorer och deskriptorer presterar i infraröda bilder. Arbetet är uppdelat i tre utvärderingar varav den första utvärderar detektorer, den andra deskriptorer och den tredje kombinationen av detektor och deskriptor. Vi finner att bäst resultat uppnås av Hessian-Affine tillsammans med LIOP men att den binära kombinationen av ORB detektor och BRISK deskriptor är ett bra alternativ som har jämförbart resultat men en ökad effektivitet av två storlekordningar.

Styles APA, Harvard, Vancouver, ISO, etc.

34

Rakotomalala, Harisoa Ny aina. « Appropriation de l'ordinateur et d'internet dans les points d'accès public : les cas comparés de Brest, de Saint-Denis de La Réunion et d'Antananarivo ». Thesis, La Réunion, 2012. http://www.theses.fr/2012LARE0015.

Texte intégral

Résumé :

Les points d'accès public à internet ou au multimédia sont des dispositifs permettant aux usagers qui les fréquentent d'utiliser les équipements numériques et d'avoir un accès à internet. Selon les structures qui en sont à l'origine et selon le public cible, plusieurs dénominations existent pour désigner ces lieux : les espaces publics numériques (EPN), les Netpublics, les cyberbases, les cybercases, les espaces culturels multimédias (ECM), les Points-cyb, les cybercommunes, les points d'accès public internet (PAPI) et les cybercafés. En France, les points d'accès public ont un double objectif : permettre à toute personne qui n'a pas les moyens de s'équiper et de se connecter à internet d'avoir accès aux outils numériques et accompagner le public à l'apprentissage et à l'utilisation des TICs. A Madagascar, les points d'accès public proposent un libre accès au public sauf que contrairement aux précédents, leur stratégie est basée sur une logique marchande. L'objectif de cette thèse est de s'interroger sur les rôles des points d'accès public auprès du public qui les fréquente dans l'appropriation de l'ordinateur et d'internet. Du point de vue théorique, la notion d'appropriation des TICs est d'abord questionnée en ayant recours à trois approches : celle de la diffusion, celle de la traduction et celle de l'appropriation. Dans un second temps, une analyse comparée des usages de l'ordinateur et d'internet dans les points d'accès public brestois, réunionnais et tananariviens permet de souligner le rôle important que jouent les facteurs sociétaux, économiques et géographiques sur les trajectoires d'appropriation des TICs. Au-delà de la définition des pratiques effectuées dans ces espaces, ce travail de recherche tente d'identifier les usagers et d'évoquer les raisons pour lesquelles ces espaces sont fréquentés. Il s'appuie sur des observations, des enquêtes par questionnaires dans 18 points d'accès public brestois, réunionnais et tananariviens complétées par des entretiens auprès des usagers sur leurs pratiques de l'ordinateur et d'internet, leur apprentissage, les raisons qui les poussent à fréquenter les points d'accès public, leur dépendance aux TICs et leurs opinions sur ces technologies
Internet access points are a place where users can access and use digital equipment and connect to internet. Various terms are used to indicate these places : « espaces publics numériques (EPN) », « Netpublics », «cyberbases », « cybercases », « espaces culturels multimédias (ECM) », « Points-cyb », « cybercommunes », « points d’accès public internet (PAPI) » and « cybercafés ». In France, internet access points help people without computer and internet access to use these technologies, to learn and to be assisted in their uses. In Madagascar, internet access points provide access to computer and internet networks but services are fee-based. The objective of this dissertation is to examine the roles of internet access points in ICTs appropriation process by public who visit these places. This research work analyses the theoretical concept of appropriation by using three approaches: the diffusion, the translation and the appropriation. This is followed by a comparative analysis of the uses of computer and internet in internet access points situated in Brest, Reunion Island and Antananarivo. The analysis shows the important role played by societal, economic and geographic contexts on ICTs appropriation. Beyond the uses of ICT in these places, this research attempts to identify users and discuss the reasons of their visits. The results are based on observations, questionnaire surveys and interviews with users in 18 internet access points in Brest, Reunion Island and Antananarivo

Styles APA, Harvard, Vancouver, ISO, etc.

35

TOCCO, MARCEL. « Interet de la comparaison evolutive du poids et du bilan entrees-sorties chez les patients hospitalises en reanimation ». Lyon 1, 1992. http://www.theses.fr/1992LYO1M351.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

36

Limpens, Freddy. « Multi-points of view semantic enrichment of folksonomies ». Phd thesis, Université de Nice Sophia-Antipolis, 2010. http://tel.archives-ouvertes.fr/tel-00530714.

Texte intégral

Résumé :

Cette thèse, au croisement du Web Social et du Web Sémantique, vise à rapprocher folksonomies et représentations structurées de connaissances telles que les thesauri ou les ontologies informatiques. Les folksonomies, résultant de l'usage de plateformes de social tagging, souffrent d'un manque de précision qui les rend difficile à exploiter pour la naviguation. Cette thèse présente notre approche multi-points de vue de l'enrichissement sémantique des folksonomies. L'amorçage est assuré par des traitements automatiques qui permettent d'extraire des relations sémantiques entre tags grâce à la combinaison d'une méthode que nous avons mise au point et analysant les labels de tags, et de méthodes que nous avons adaptées et analysant la structure de folksonomies. Les contributions des utilisateurs sont décrites par notre modèle SRTag supportant les points de vue divergents, et capturées par une interface intégrant à la navigation des fonctionnalités de micro-édition de folksonomie. Les conflits entre points de vue sont détectés et solutionnés par un agent automatique dont les résultats sont ensuite exploités pour aider un utilisateur référent à maintenir une structuration globale et cohérente de la folksonomie, servant en retour pour enrichir chaque point de vue individuel avec les autres contributions tout en garantissant une cohérence locale. Notre méthode permet d'améliorer la navigation dans les systèmes de connaissances à base de tags, mais fournit aussi une base à des thesauri nourris par un processus bottom-up d'acquisition de connaissances.

Styles APA, Harvard, Vancouver, ISO, etc.

37

Roos, Jan Corver S. M. Massachusetts Institute of Technology. « System development considerations and point of interest guidance of an unmanned aerial system for remote sensing in commercial application ». Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/106261.

Texte intégral

Résumé :

Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, School of Engineering, System Design and Management Program, Engineering and Management Program, 2016.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 78-79).
The objective of this thesis is to develop a contextual and system level understanding of an ISR (Intelligence, Surveillance and Reconnaissance) Unmanned Aerial System (UAS) for commercial application. The thesis is intended to support strategic decision making for creating and capturing value in the emerging Unmanned Aerial Vehicle (UAV) industry and to support system design decisions. As an example of a system design decision, a flight control capability to enable directing the flight of a UAV through the steering of the optical payload only is also proposed and developed. This flight control capability is intended to more closely align the operation of an ISR unmanned aerial system with the identified primary user need. Thus, the development presented here could be useful to the prospective entrepreneur or an established organization who would like to build a presence in the emerging commercial application of unmanned aircraft. Towards these objectives, four aspects are considered: 1. To develop an understanding of the current state of the emerging commercial unmanned aircraft industry. 2. Understanding the current and potential future regulatory requirements associated with the commercial operation of unmanned aircraft. 3. To develop a system design understanding of an ISR unmanned aerial system which includes identifying the primary need, developing a stakeholder value network, identifying the principle elements of form and understanding the principle internal functions. 4. Propose and develop a flight control capability which enables directing the flight of a UAV through the steering of the optical payload only. This flight control capability serves as a system design example to more closely align the operation of an ISR unmanned aerial system with the identified primary user need.
by Jan Corver Roos.
S.M. in Engineering and Management

Styles APA, Harvard, Vancouver, ISO, etc.

38

Parisot, Pascaline. « Suivi d’objets dans des séquences d’images de scènes déformables : de l’importance des points d’intérêt et du maillage 2D ». Thesis, Toulouse, INPT, 2009. http://www.theses.fr/2009INPT012H/document.

Texte intégral

Résumé :

Nous abordons le suivi d’objets dans des séquences d’images de scènes déformables selon deux axes de recherche. Il s’agit de déterminer les transformations d’un objet, d’une image à l’autre, lorsque celui-ci s’est éventuellement déformé ou déplacé et lorsque le point de vue de la caméra a éventuellement été modifié (déplacement, zoom...). Pour cela, nous nous sommes inspirés de l’algorithme de Jurie et Dhome qui permet de suivre un objet plan indéformable. D’une part, nous en améliorons les performances. D’autre part, nous le généralisons au cas d’objets déformables. Le premier axe de recherche consiste à améliorer les performances de l’algorithme de Jurie et Dhome en termes de précision et robustesse. Le suivi s’appuie sur un ensemble de points d’intérêt, dont dépendent fortement les performances. Ces points d’intérêt sont issus d’une sélection des points obtenus par des détecteurs reconnus, à savoir SIFT, KLT, SUSAN, HARRIS et MORAVEC. Nous avons étudié et mis en oeuvre, sur différentes classes d’images, des heuristiques de sélection fondées sur des approches statistique et algébrique. Nous montrons : – qu’il n’existe pas de détecteur universel, – que l’approche statistique est à privilégier dans tous les cas. Le second axe de recherche est une proposition d’un nouvel algorithme de suivi s’appuyant sur le maillage 2D des images de la séquence. Cet algorithme généralise celui de Jurie et Dhome aux scènes déformables. Il repose sur : – des transformations élémentaires (nodales) du maillage, directes et inverses, que nous avons caractérisées tant d’un point de vue géométrique qu’analytique, – l’utilisation des coordonnées barycentriques généralisées pour approcher la composition de deux transformations d’un maillage. Cet algorithme donne des résultats similaires à celui d’appariement hexagonal de Nakaya et Harashima tout en étant plus rapide
We deal with object tracking in videos of non-rigid scenes with two main purposes. We aim at determining the transformations of an object, from one frame to the next, when it may be distorted or moved and when the camera focus may change (movement, zoom...). To do this, we were inspired by the Jurie and Dhome algorithm, which enables the tracking of plane rigid objects. On the one hand, we improve its performance. On the other hand, we generalize it to non-rigid objects. The first goal consists in improving the performance of the Jurie and Dhome algorithm, in terms of accuracy and robustness. The tracking is based on a set of interest points, which has a great effect on the algorithm’s performance. These interest points come from a selection among the points extracted with some common detectors: SIFT, KLT, SUSAN, HARRIS, and MORAVEC.With various pictures classes, we have studied and implemented some selection heuristics based on statistical or algebraic approaches. We show that : • there is no universal detector, • the statistical approach is the best in all cases. The second goal is a proposal of a new tracking algorithm based on a 2D mesh of the video frames. This algorithm generalizes the Jurie and Dhome one for non-rigid scenes. It is based on : • elementary (nodal), direct or inverse, mesh transformations that we geometrically and analytically characterize, • generalized barycentric coordinates to approximate the composition of two mesh transformations. This algorithm gives similar results to the hexagonal matching algorithm of Nakaya and Harashima while being faster

Styles APA, Harvard, Vancouver, ISO, etc.

39

Dias, Alessandro da Silveira. « Aumentando a acurácia de predição de avaliação de sistemas de recomendação de vídeo com o uso de pontos de interesse ». reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2013. http://hdl.handle.net/10183/71271.

Texte intégral

Résumé :

A cada dia aumenta o número de vídeos disponíveis no mundo. Por exemplo, há uma vasta quantidade de sites de vídeos disponíveis na Web e serviços de Vídeo Sob Demanda além de dispositivos que fazem a gravação de vídeos automaticamente, conhecidos como Personal Video Recorders, 24 horas por dia. Isso pode ocasionar um problema ao usuário: a sobrecarga de conteúdo em formato de vídeo. Uma das maneiras de se tratar tal problema consiste no uso de sistemas de recomendação, os quais filtram o conteúdo com o objetivo de entregar o que for mais interessante ao usuário. A abordagem típica utilizada pelos sistemas atuais consiste em um sistema de recomendação híbrido, i.e., que utiliza tanto filtragem baseada em conteúdo quanto filtragem colaborativa, minimizando os problemas que tais abordagens possuem individualmente. Adicionalmente, com o objetivo de melhorar a recomendação ou de criar novas formas de recomendação, têm sido apresentadas novas abordagens, tais como sistemas de recomendação utilizando dados de redes sociais, computação afetiva, tags, entre outros. Este trabalho tem como objetivo apresentar uma abordagem inovadora, a qual utiliza pontos de interesse em vídeo de usuários (ou seja, os segmentos dos vídeos que eles mais gostam ou que mais se interessam) para melhorar a acurácia de predição de sistemas de recomendação de vídeo que utilizam filtragem colaborativa baseados na abordagem usuário-usuário. Na abordagem proposta, os usuários participam de forma mais ativa e mais interativa ao marcarem seus pontos de interesse. Para avaliação de tal abordagem proposta foi realizada uma avaliação experimental em termos de acurácia de predição de avaliação; pela qual constatou-se que houve melhora na predição de avaliação do sistema de recomendação. Tal melhora está diretamente relacionada com o nível de participação das pessoas na marcação de pontos de interesse.
Every day the number of videos available in the world increases. For example, there is a vast amount of video sites available on the Web, Video On Demand services, as well as devices that records videos automatically, known as Personal Video Recorders, 24 hours a day. It may create a problem for the user: the overload of content in video format. One of the ways to treat such problem is the use of recommender systems, which filter the content in order to deliver what is most interesting to the user. The typical approach is to present a hybrid recommender system, i.e., that uses both contentbased filtering and collaborative filtering, minimizing the problems that these approaches have individually. Additionally, in order to improve the recommendation or to create new approaches of recommendation, has been given new approaches such as systems using data from social networks, affective computing, tags, etc. This paper aims to present an innovative approach, which uses points of interest (POI) in video of users (i.e., video segments best liked or most interested by them) to augment the prediction accuracy of video recommender systems with collaborative filtering based in the useruser approach. In the proposed approach, users participate more actively and more interactively to mark their points of interest. To evaluate this proposed approach an experimental evaluation was performed in terms of accuracy of ratings predictions; in which it was verified that there was an improvement in ratings prediction accuracy of the recommendation system. This improvement is directly related to the level of participation of people in marking points of interest.

Styles APA, Harvard, Vancouver, ISO, etc.

40

COCHARD, PHILIPPE. « Deux incidences sous-acromiales en radiographie simple : mise au point et interet pour la chirurgie du syndrome du conflit ». Lyon 1, 1991. http://www.theses.fr/1991LYO1M296.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

41

Seltz, Francis. « Quelques reactions somato-psychiques a point de depart tactile : mise en evidence, tentative de modelisation, interet pour le medecin ». Université Louis Pasteur (Strasbourg) (1971-2008), 1990. http://www.theses.fr/1990STR1M134.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

42

JOUBAUD, PATRICK. « Interet et limite de l'immunoenzymologie dans le diagnostic des candidoses profondes : mise au point et evaluation sur 444 serums ». Strasbourg 1, 1991. http://www.theses.fr/1991STR15071.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

43

Youness, Chebli. « L'e-réputation du point de vue client : modèle intégrateur et échelle de mesure ». Thesis, Université Grenoble Alpes (ComUE), 2016. http://www.theses.fr/2016GREAG016.

Texte intégral

Résumé :

Bien que la réputation en ligne ait attiré une attention particulière parmi les praticiens en marketing, la recherche dans ce domaine est encore limitée. Dans ce travail doctoral, les auteurs examinent les antécédents et les conséquences de l’e-réputation du point de vue client. Une approche selon un modèle d’équations structurelles est utilisée pour tester le modèle basé sur les données d’une enquête auprès de 1097 acheteurs en ligne français. Les résultats montrent l’impact de la confiance, l’héritage et la qualité du site sur l’e-réputation, ainsi que la façon dont l’e-réputation affecte l’engagement du client, le bouche à oreille, le risque perçu et la valeur perçue. Plusieurs implications managériales et théoriques sont ensuite discutées
Although online reputation has attracted significant attention among marketing practitioners, research in this area is still limited. In this research dissertation, the authors examine the antecedents and consequences of online reputation from the customer’s perspective. A structural equation modeling approach is used to test the model based on data from a survey of 1097 French online buyers. The results show the impact of trust, heritage, and website quality on online reputation, as well as how online reputation affects customer commitment, word of mouth, perceived risk, and perceived value. Several implications either in terms of conceptual or managerial insights are then discussed

Styles APA, Harvard, Vancouver, ISO, etc.

44

Lu, Wanting. « Financial reforms, divided interests, and tipping point policy-making : renminbi internationalization as a new catalyst for structural reforms in China ». Thesis, University of British Columbia, 2016. http://hdl.handle.net/2429/57944.

Texte intégral

Résumé :

China’s RMB has been making quiet march onto the world stage, first into focus in the aftermath of the 2008 financial crisis, and notably gathering pace after 2012. By examining the seeming puzzle of why RMB internationalization, after a long albeit methodical trudge, accelerated after 2012, this paper seeks to offer a theory that could explain the motivations behind China’s pursuit of RMB internationalization. I argue that the existing approaches to this question, which primarily looks to the traditional economic factors such as relative national economic fundamentals, cost/benefit of currency internationalization, and impact of external shocks, fall short of explaining the timing, pace and trajectory of the RMB internationalization process. I maintain instead that the source of the dynamics driving RMB internationalization should be located in the structure of political decision making and political imperatives of the key players in the decision making process. This paper contends that RMB internationalization should above all be viewed in the broad context of China’s next round of reforms that centers on liberalizing the financial sector and developing the capital markets. Putting Chinese political decision making in the perspective of fragmented authoritarianism, this paper argues that with the balance of power of interest group coalitions favoring status quo or change in a deadlock, a lever is needed to break the stalemate and tip the balance toward reforms. Recognizing the need for financial reforms as China increasingly reaches the limit of its export-led growth model, political entrepreneurs at PBOC, under the personal leadership of Governor Zhou Xiaochuan and buttressed by the superior institutional resources and capacity, promoted RMB internationalization as the key lever to redistribute incentives and realign underlying coalitions. Capitalizing on favorable changes at the party’s top taking place post the power transition, which brought about a degree of centralization of the financial policy decision making that wasn’t available previously, Zhou Xiaochuan and his fellow political entrepreneurs were able to push forward RMB internationalization more effectively that both exposed the need for further financial sector reforms and generated broader support to tip the balance of power toward reforms.
Arts, Faculty of
Political Science, Department of
Graduate

Styles APA, Harvard, Vancouver, ISO, etc.

45

Livardjani, Fariborz. « Mise au point d'un appareil portable de dosage du mercure : interet, methodologies et applications en toxicologie animale, humaine et environnementale ». Strasbourg 1, 1996. http://www.theses.fr/1996STR15112.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

46

Grigaravičienė, Regina. « Elektroninės valdžios įtaka visuomenei ». Master's thesis, Lithuanian Academic Libraries Network (LABT), 2006. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2005~D_20060317_140521-34733.

Texte intégral

Résumé :

Theses deal with opportunities of e-government, possible changes in the society after implementation of e-government projects, provision of high level electronic public services (EPS) which are recommended by the EU program documents. They also analyse supply and demand of e-government services in the society, level of society satisfaction by e-government services, influence of e-government to the sphere of rapidly developing and improving technologies. Theses present and analyse samples of e-government services of foreign countries which enable to assess shortcomings of services, future perspectives of other countries. Theses analyse e-government situation in Lithuania.

Styles APA, Harvard, Vancouver, ISO, etc.

47

Walter, Nicolas. « Détection de primitives par une approche discrète et non linéaire : application à la détection et la caractérisation de points d'intérêt dans les maillages 3D ». Phd thesis, Université de Bourgogne, 2010. http://tel.archives-ouvertes.fr/tel-00808216.

Texte intégral

Résumé :

Ce manuscrit est dédié à la détection et la caractérisation de points d'intérêt dans les maillages. Nous montrons tout d'abord les limitations de la mesure de courbure sur des contours francs, mesure habituellement utilisée dans le domaine de l'analyse de maillages. Nous présentons ensuite une généralisation de l'opérateur SUSAN pour les maillages, nommé SUSAN-3D. La mesure de saillance proposée quantifie les variations locales de la surface et classe directement les points analysés en cinq catégories : saillant, crête, plat, vallée et creux. Les maillages considérés sont à variété uniforme avec ou sans bords et peuvent être réguliers ou irréguliers, denses ou non et bruités ou non. Nous étudions ensuite les performances de SUSAN-3D en les comparant à celles de deux opérateurs de courbure : l'opérateur de Meyer et l'opérateur de Stokely. Deux méthodes de comparaison des mesures de saillance et courbure sont proposées et utilisées sur deux types d'objets : des sphères et des cubes. Les sphères permettent l'étude de la précision sur des surfaces différentiables et les cubes sur deux types de contours non-différentiables : les arêtes et les coins. Nous montrons au travers de ces études les avantages de notre méthode qui sont une forte répétabilité de la mesure, une faible sensibilité au bruit et la capacité d'analyser les surfaces peu denses. Enfin, nous présentons une extension multi-échelle et une automatisation de la détermination des échelles d'analyse qui font de SUSAN-3D un opérateur générique et autonome d'analyse et de caractérisation pour les maillages

Styles APA, Harvard, Vancouver, ISO, etc.

48

Ledan, Antoine Le Néel Tanguy. « Celesio® et " OCP point " présentation, description et étude en 2005 / ». [S.l.] : [s.n.], 2005. http://theses.univ-nantes.fr/thesemed/PHledan.pdf.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

49

Agier, Rémi. « Recalage de groupes d’images médicales 3D par extraction de points d’intérêt ». Thesis, Lyon, 2017. http://www.theses.fr/2017LYSEI093/document.

Texte intégral

Résumé :

Les imageurs des hôpitaux produisent de plus en plus d'images 3D et il y a un nombre croissant d'études de cohortes. Afin d'ouvrir la voie à des méthodes utilisant de larges bases de données, il est nécessaire de développer des approches permettant de rendre ces bases cohérentes en recalant les images. Les principales méthodes actuelles de recalage de groupes utilisent des données denses (voxels) et sélectionnent une référence pour mettre en correspondance l'ensemble des images. Nous proposons une approche de recalage par groupes, sans image de référence, en utilisant seulement des points d'intérêt (Surf3D), applicable à des bases de plusieurs centaines d'images médicales. Nous formulons un problème global fondé sur l'appariement de points d'intérêt. La variabilité inter-individu étant grande, le taux de faux positifs (paires aberrantes) peut être très important (70\%). Une attention particulière est portée sur l'élimination des appariements erronés. Une première contribution effectue le recalage rigide de groupes d'images. Nous calculons les recalages de toutes les paires d'images. En s'appuyant sur le graphe complet de ces recalages, nous formulons le problème global en utilisant l'opérateur laplacien. Des expérimentations avec 400 images scanner CT 3D hétérogènes illustrent la robustesse de notre méthode et sa vitesse d'exécution. Une seconde contribution calcule le recalage déformable de groupes d'images. Nous utilisons des demi-transformations, paramétrées par des pyramides de B-splines, entre chaque image et un espace commun. Des comparaisons sur un jeu de données de référence montrent que notre approche est compétitive avec la littérature tout en étant beaucoup plus rapide. Ces résultats montrent le potentiel des approches basées sur des points d'intérêt pour la mise en correspondance de grandes bases d'images. Nous illustrons les perspectives de notre approche par deux applications : la segmentation multi-atlas et l'anthropologie
The ever-increasing amount of medical images stored in hospitals offers a great opportunity for big data analysis. In order to pave the way for huge image groups screening, we need to develop methods able to make images databases consistent by group registering those images. Currently, group registration methods generally use dense, voxel-based, representations for images and often pick a reference to register images. We propose a group registration framework, without reference image, by using only interest points (Surf3D), able to register hundreds of medical images. We formulate a global problem based on interest point matching. The inter-patient variability is high, and the outliers ratio can be large (70\%). We pay a particular attention on inhibiting outliers contribution. Our first contribution is a two-step rigid groupwise registration. In the first step, we compute the pairwise rigid registration of each image pair. In a second step, a complete graph of those registrations allows us to formulate a global problem using the laplacian operator. We show experimental results for groups of up to 400 CT-scanner 3D heterogeneous images highlighting the robustness and speed of our approach. In our second contribution, we compute a non-rigid groupwise registration. Our approach involves half-transforms, parametrized by a b-spline pyramid, between each image and a common space. A reference dataset shows that our algorithm provides competitive results while being much faster than previous methods. Those results show the potential of our interest point based registration method for huge datasets of 3D medical images. We also provide to promising perspectives: multi-atlas based segmentation and anthropology

Styles APA, Harvard, Vancouver, ISO, etc.

50

Bégin, Mathieu. « La cyberintimidation une étude exploratoire sur le point de vue des adolescents ». Mémoire, Université de Sherbrooke, 2011. http://hdl.handle.net/11143/5662.

Texte intégral

Résumé :

Depuis quelques années, on entend de plus en plus parler de la cyberintimidation, un phénomène associé à l'usage d'Internet et des technologies numériques par les jeunes. Selon plusieurs recherches, les jeunes victimes de cyberintimidation subiraient d'importants problèmes sur les plans psychosocial, affectif et scolaire. Le taux de victimisation rapporté par les enquêtes au sujet de ce phénomène est cependant très variable : il se situe généralement entre 20% et 40%, mais dépasse parfois les 70%. Cette disparité s'avère attribuable à une variation dans la conceptualisation du terme"cyberintimidation" au sein de la communauté de chercheurs qui s'intéressent à ce phénomène. C'est pourquoi il s'avérait pertinent d'étudier la manière dont les jeunes eux-mêmes se représentent et définissent la cyberintimidation. Cette étude exploratoire, qui s'inscrit dans la tradition des études de réception des médias, vise à étudier la cyberintimidation selon la perspective des jeunes, à travers l'ensemble de leurs usages d'Internet et de leurs interactions sociales. Pour ce faire, 20 entretiens individuels en profondeur ont été menés auprès de neuf filles et de onze garçons âgés entre 12 et 18 ans. Une approche inductive a été adoptée pour l'analyse des données issues de ces entretiens. Ce mémoire confronte les définitions du terme"cyberintimidation", proposées par différents chercheurs, avec le point de vue des jeunes interrogés au sujet de leur perception de ce phénomène. On y explique que la cyberintimidation ne se limite pas à un nouveau type d'intimidation ou à un risque associé à l'usage d'Internet et des technologies numériques par les jeunes, mais qu'elle doit plutôt être vue comme un phénomène social complexe. Selon les résultats présentés dans ce mémoire, la cyberintimidation est liée à certaines réalités vécues par les jeunes, comme la quête de la popularité, la pression des pairs, l'importance de l'apparence physique, etc. On souligne finalement l'importance de tenir compte de ces réalités dans le cadre de futures recherches sur la cyberintimidation, de même que dans l'élaboration des campagnes de sensibilisation dédiées aux jeunes. Une réflexion critique au sujet de la recherche et des démarches d'intervention portant sur la cyberintimidation est présentée en conclusion.

Styles APA, Harvard, Vancouver, ISO, etc.

Thèses sur le sujet « Interets points »

Créez une référence correcte selon les styles APA, MLA, Chicago, Harvard et plusieurs autres