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Space-efficient data sketching algorithms for network applicationsHua, Nan 06 July 2012 (has links)
Sketching techniques are widely adopted in network applications. Sketching algorithms “encode” data into succinct data structures that can later be accessed and “decoded” for various purposes, such as network measurement, accounting, anomaly detection and etc. Bloom filters and counter braids are two well-known representatives in this category. Those sketching algorithms usually need to strike a tradeoff between performance (how much information can be revealed and how fast) and cost (storage, transmission and computation). This dissertation is dedicated to the
research and development of several sketching techniques including improved forms of stateful Bloom Filters, Statistical Counter Arrays and Error Estimating Codes. Bloom filter is a space-efficient randomized data structure for approximately representing a set in order to support membership queries. Bloom filter and its variants have found widespread use in many networking applications, where it is important to minimize the cost of storing and communicating network data. In this thesis, we propose a family of Bloom Filter variants augmented by rank-indexing method. We will show such augmentation can bring a significant reduction of space and also the number of memory accesses, especially when deletions of set elements from the Bloom Filter need to be supported. Exact active counter array is another important building block in many sketching algorithms, where storage cost of the array is of paramount concern. Previous approaches reduce the storage costs while either losing accuracy or supporting only passive measurements. In this thesis, we propose an exact statistics counter array architecture that can support active measurements (real-time read and write). It also leverages the aforementioned rank-indexing method and exploits statistical multiplexing to minimize the storage
costs of the counter array. Error estimating coding (EEC) has recently been established as an important tool to estimate bit error rates in the transmission of packets over wireless links. In essence, the EEC problem is also a sketching problem, since the EEC codes can be viewed as a sketch of the packet sent, which is decoded by the receiver to estimate bit error rate. In this thesis, we will first investigate the asymptotic bound of error estimating coding by viewing the problem from two-party computation perspective and then investigate its coding/decoding efficiency using Fisher information analysis. Further, we develop several sketching techniques including Enhanced tug-of-war(EToW) sketch and the generalized EEC (gEEC)sketch family which can achieve around 70% reduction of sketch size with similar estimation accuracies. For all solutions proposed above, we will use theoretical tools such as information theory and communication complexity to investigate how far our proposed solutions are away from the theoretical optimal. We will show that the proposed techniques are asymptotically or empirically very close to the theoretical bounds.
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Kinematic Templates: Guiding Cursor Movement in End-User Drawing ToolsFung, Richard Hai-Ping 08 1900 (has links)
This thesis presents kinematic templates, end-user drawing tools that influence the mouse cursor's movement within specific areas of a digital canvas. Two types of kinematic templates influence the cursor's movement: passive and active templates. Passive templates modify existing movement received from a pointing device to change the cursor's speed or direction of one's stroke. Active templates add movement to the cursor without movement from the pointing device. Since templates are provided as user-specified regions, these regions can be associated with areas of detail and they can be overlapped as a means of function composition. [¶]
A kinematic template can be configured to improve upon one's freehand output without producing perfect output. Since templates do not necessarily prescribe geometric output, they constitute a visual composition aid that lies between unaided freehand drawing and drawing aids such as snapping constraints and perfect geometric primitives. [¶]
Since kinematic templates can improve upon the consistency of one's strokes, it is beneficial for drawing visual styles such as hatching (an artistic effect that adds depth to a drawing with uniform strokes drawn in close proximity) and repetitive patterns. Since kinematic templates do not prescribe a type of output, one can "fight against" a template's preferred path of movement and discover unexpected, serendipitous outcomes.
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Design of an intelligent posture guidance system for workspace seating.Jalasutram, Srikanth 06 June 2011 (has links)
Seating is an integral part of work environment. When people are at work, they often sit in chairs for long periods of time without changing postures. This results in reduced blood circulation in the body, especially in the buttock-thigh area causing muscle fatigue, pain and discomfort. Ergonomically designed task chairs adopt a passive approach to guiding people into better postures by providing adjustability inside the chair. However most people do not adjust their chairs because they fail to sense the need for changing posture. They are left to sensing the need to change posture through guesswork or extreme discomfort. This thesis proposes a new system to address this problem by sensing static posture in a seated person with the use of electronic sensors embedded in the seat, and by providing interactive feedback to static posture via sound, light and tactile channels. The new technology is an sensing-feedback mechanism embedded in a chair, that allows people to receive postural information and make body adjustments periodically to avoid pain and discomfort caused by prolonged seating.The feedback mechanism was tested with four subjects to determine its efficacy in generating posture change through pressure relief and user feedback was gathered in order to design the final prototype.
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Die frühen Phasen des konstruktiven Entwerfens - Unterstützungspotential verschiedenartiger ArbeitsmittelSchütze, Martina 08 November 2003 (has links) (PDF)
Vor dem Hintergrund empirischer Befunde zur Nutzung von CAD-Systemen beim konstruktiven Entwerfen in der Ausbildung sowie der Berufspraxis wird in der vorliegenden Arbeit über eine Befragungsstudie sowie eine laborexperimentelle Studie zur Bewertung des Unterstützungspotentials verschiedenartiger Arbeitsmittel in den frühen Phasen des Entwerfens von technischen Gebilden berichtet. Zu den beim Entwerfen eingesetzten Arbeitsmitteln zählen neben einfachen, aufwandsarmen Werkzeugen wie Papier und Bleistift auch computerisierte Automaten wie z. B. CAD-Systeme. CAD-Systeme sind durch die bereitgestellten Funktionalitäten heutzutage ein wesentliches Arbeitsmittel für den Konstrukteur; die für die außerordentlich komplexen, kostenbestimmenden frühen Entwurfsphasen wichtigen Funktionen werden aber offenbar nur in unzureichendem Maße oder überhaupt nicht zur Verfügung gestellt. Dadurch notwendige Wechsel zwischen analogen und digitalen Arbeitsmitteln müssen bislang manuell durchgeführt werden und haben neben zeitlichen Einbußen in der Regel Fehler und Informationsverluste bei der Übertragung zur Folge. Mit dem LCD-Monitor mit integriertem Graphiktablett WACOM Cintiq 15X, dessen Bedienung sich an den Eigenschaften herkömmlicher Handskizzen orientiert, wird eine durchgängige Nutzung von CAD-Systemen angestrebt. Zunächst wurden diese drei Arbeitsmittel hinsichtlich Ihrer Anforderungen an den Nutzer bei einem Einsatz in den frühen Entwurfsphasen aus tätigkeitspsychologischer Sicht analysiert. In der experimentellen Hauptuntersuchung bearbeiteten drei Versuchsgruppen einer Stichprobe von 66 Studierenden einer ingenieurtechnischen Fakultät dasselbe wissensreiche, praxisnahe Entwurfsproblem unter den experimentellen Bedingungen der Entwurfsentwicklung durch Freihandskizzieren mit Papier und Bleistift, mit digitalem Graphiktablett oder mit Hilfe des Rechnerprogramms AutoCAD. Es erfolgte eine differenzierte Betrachtung des Einflusses dieser verschiedenartigen Arbeitsmittel auf unterschiedliche Variablen der Bereiche ?Ergebnisse?, ?Erleben? und ?Prozess?. Im Ergebnis der Analysen konnte weitestgehend hypothesenkonform gezeigt werden, dass Freihandskizzieren - unabhängig vom Arbeitsmittel - dem Entwerfen mittels CAD in allen betrachteten effektivitäts- und effizienzbestimmenden Kriterien überlegen war. Prozessorientierte Analysen des äußeren Handlungsablaufes sowie handlungsbegleitender mentaler Prozesse gaben erste Hinweise auf mögliche Ursachen dieser Befunde aus handlungspsychologischer Sicht. Dazu war eine Untersuchungsmethodik entwickelt worden, die es erlaubt, begründet auf den ?inneren Verlauf? des Entwerfens zu schließen. Die Ergebnisse konnten in einem weiteren Schritt an einer Problemstellung mit vergleichbarem Schwierigkeitsgrad weitgehend repliziert werden. Aus den Analysen und Resultaten wurden Schlussfolgerungen für die Konstruktionsausbildung und die Gestaltung digitaler Unterstützungssysteme abgeleitet. / Due to its economic importance, engineering design as a demanding and complex problem-solving activity has been the subject of interdisciplinary research of both psychologists and design scientists for several years. In particular, the early stages of problem clarification and conceptual design are of significant interest. The design process can be supported in several different ways, e. g. with simple low-expenditure sketches. Today, high-performance digital tools (e. g. CAD) have become indispensable in product development. But their characteristics hypothetically result in an additional workload of mental capacity and hinder the full and correct establishment of necessary mental problem representations. So design engineers often combine sketches and CAD. In order to avoid a loss of time and information when switching between the different media, the functions of sketches should be implemented into CAD. An approach to realise this is the interactive pen display WACOM Cintiq 15X, which claims to have the same characteristics as paper & pencil together with differing kinds of computer functionalities. Its effectiveness and efficiency has not yet been investigated. This study focuses on the comparison of the three media ?paper & pencil?, ?pen display? and ?AutoCAD? in the early stages of the design process. On the basis of the psychological demands on the user, support potential was analysed by recording variables concerning the results, the subjective experience and the process. The sample was composed of 66 students of the mechanical engineering graduate program at the Dresden University of Technology. Random sampling resulted in three subsamples of 22 subjects each. The research was carried out in a laboratory experimental study, where people work alone on a given design scenario. No significant differences could be found between the two groups designing by freehandsketching with paper & pencil and with pen display. This speaks well for comparable demands of these two media on the user. Subjects who designed with AutoCAD produced solutions with a significant lower quality and communication of the technical information content. They needed significantly more time to develop the solution. These results can be regarded as evidence of the hypothetically discussed demands on the user: current CAD-systems do not take cognitive abilities and limitations into consideration sufficiently as well as ways of intuitive and effort-saving externalisation. Results could be replicated extensively in a study with a design problem of equally difficult requirement structure. Finally, hints for education of engineering design students and essential requirements for digital support tools in the early stages of the design process were derived.
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Template-basierte Klassifikation planarer GestenSchmidt, Michael 09 July 2014 (has links) (PDF)
Pervasion of mobile devices led to a growing interest in touch-based interactions. However, multi-touch input is still restricted to direct manipulations. In current applications, gestural commands - if used at all - are only exploiting single-touch. The underlying motive for the work at hand is the conviction that a realization of advanced interaction techniques requires handy tools for supporting their interpretation. Barriers for own implementations of procedures are dismantled by providing proof of concept regarding manifold interactions, therefore, making benefits calculable to developers. Within this thesis, a recognition routine for planar, symbolic gestures is developed that can be trained by specifications of templates and does not imply restrictions to the versatility of input. To provide a flexible tool, the interpretation of a gesture is independent of its natural variances, i.e., translation, scale, rotation, and speed. Additionally, the essential number of specified templates per class is required to be small and classifications are subject to real-time criteria common in the context of typical user interactions. The gesture recognizer is based on the integration of a nearest neighbor approach into a Bayesian classification method.
Gestures are split into meaningful, elementary tokens to retrieve a set of local features that are merged by a sensor fusion process to form a global maximum-likelihood representation. Flexibility and high accuracy of the approach is empirically proven in thorough tests. Retaining all requirements, the method is extended to support the prediction of partially entered gestures. Besides more efficient input, the possible specification of direct manipulation interactions by templates is beneficial. Suitability for practical use of all provided concepts is demonstrated on the basis of two applications developed for this purpose and providing versatile options of multi-finger input. In addition to a trainable recognizer for domain-independent sketches, a multi-touch text input system is created and tested with users. It is established that multi-touch input is utilized in sketching if it is available as an alternative. Furthermore, a constructed multi-touch gesture alphabet allows for more efficient text input in comparison to its single-touch pendant. The concepts presented in this work can be of equal benefit to UI designers, usability experts, and developers of feedforward-mechanisms for dynamic training methods of gestural interactions. Likewise, a decomposition of input into tokens and its interpretation by a maximum-likelihood matching with templates is transferable to other application areas as the offline recognition of symbols. / Obwohl berührungsbasierte Interaktionen mit dem Aufkommen mobiler Geräte zunehmend Verbreitung fanden, beschränken sich Multi-Touch Eingaben größtenteils auf direkte Manipulationen. Im Bereich gestischer Kommandos finden, wenn überhaupt, nur Single-Touch Symbole Anwendung. Der vorliegenden Arbeit liegt der Gedanke zugrunde, dass die Umsetzung von Interaktionstechniken mit der Verfügbarkeit einfach zu handhabender Werkzeuge für deren Interpretation zusammenhängt. Auch kann die Hürde, eigene Techniken zu implementieren, verringert werden, wenn vielfältige Interaktionen erprobt sind und ihr Nutzen für Anwendungsentwickler abschätzbar wird. In der verfassten Dissertation wird ein Erkenner für planare, symbolische Gesten entwickelt, der über die Angabe von Templates trainiert werden kann und keine Beschränkung der Vielfalt von Eingaben auf berührungsempfindlichen Oberflächen voraussetzt. Um eine möglichst flexible Einsetzbarkeit zu gewährleisten, soll die Interpretation einer Geste unabhängig von natürlichen Varianzen - ihrer Translation, Skalierung, Rotation und Geschwindigkeit - und unter wenig spezifizierten Templates pro Klasse möglich sein. Weiterhin sind für Nutzerinteraktionen im Anwendungskontext übliche Echtzeit-Kriterien einzuhalten. Der vorgestellte Gestenerkenner basiert auf der Integration eines Nächste-Nachbar-Verfahrens in einen Ansatz der Bayes\'schen Klassifikation.
Gesten werden in elementare, bedeutungstragende Einheiten zerlegt, aus deren lokalen Merkmalen mittels eines Sensor-Fusion Prozesses eine Maximum-Likelihood-Repräsentation abgeleitet wird. Die Flexibilität und hohe Genauigkeit des statistischen Verfahrens wird in ausführlichen Tests nachgewiesen. Unter gleichbleibenden Anforderungen wird eine Erweiterung vorgestellt, die eine Prädiktion von Gesten bei partiellen Eingaben ermöglicht. Deren Nutzen liegt - neben effizienteren Eingaben - in der nachgewiesenen Möglichkeit, per Templates spezifizierte direkte Manipulationen zu interpretieren. Zur Demonstration der Praxistauglichkeit der präsentierten Konzepte werden exemplarisch zwei Anwendungen entwickelt und mit Nutzern getestet, die eine vielseitige Verwendung von Mehr-Finger-Eingaben vorsehen. Neben einem Erkenner trainierbarer, domänenunabhängiger Skizzen wird ein System für die Texteingabe mit den Fingern bereitgestellt. Anhand von Nutzerstudien wird gezeigt, dass Multi-Touch beim Skizzieren verwendet wird, wenn es als Alternative zur Verfügung steht und die Verwendung eines Multi-Touch Gestenalphabetes im Vergleich zur Texteingabe per Single-Touch effizienteres Schreiben zulässt. Von den vorgestellten Konzepten können UI-Designer, Usability-Experten und Entwickler von Feedforward-Mechanismen zum dynamischen Lehren gestischer Eingaben gleichermaßen profitieren. Die Zerlegung einer Eingabe in Token und ihre Interpretation anhand der Zuordnung zu spezifizierten Templates lässt sich weiterhin auf benachbarte Gebiete, etwa die Offline-Erkennung von Symbolen, übertragen.
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A multidimensional sketching interface for visual interaction with corpus-based concatenative sound synthesisTsiros, Augoustinos January 2016 (has links)
The present research sought to investigate the correspondence between auditory and visual feature dimensions and to utilise this knowledge in order to inform the design of audio-visual mappings for visual control of sound synthesis. The first stage of the research involved the design and implementation of Morpheme, a novel interface for interaction with corpus-based concatenative synthesis. Morpheme uses sketching as a model for interaction between the user and the computer. The purpose of the system is to facilitate the expression of sound design ideas by describing the qualities of the sound to be synthesised in visual terms, using a set of perceptually meaningful audio-visual feature associations. The second stage of the research involved the preparation of two multidimensional mappings for the association between auditory and visual dimensions. The third stage of this research involved the evaluation of the Audio-Visual (A/V) mappings and of Morpheme's user interface. The evaluation comprised two controlled experiments, an online study and a user study. Our findings suggest that the strength of the perceived correspondence between the A/V associations prevails over the timbre characteristics of the sounds used to render the complementary polar features. Hence, the empirical evidence gathered by previous research is generalizable/ applicable to different contexts and the overall dimensionality of the sound used to render should not have a very significant effect on the comprehensibility and usability of an A/V mapping. However, the findings of the present research also show that there is a non-linear interaction between the harmonicity of the corpus and the perceived correspondence of the audio-visual associations. For example, strongly correlated cross-modal cues such as size-loudness or vertical position-pitch are affected less by the harmonicity of the audio corpus in comparison to weaker correlated dimensions (e.g. texture granularity-sound dissonance). No significant differences were revealed as a result of musical/audio training. The third study consisted of an evaluation of Morpheme's user interface were participants were asked to use the system to design a sound for a given video footage. The usability of the system was found to be satisfactory. An interface for drawing visual queries was developed for high level control of the retrieval and signal processing algorithms of concatenative sound synthesis. This thesis elaborates on previous research findings and proposes two methods for empirically driven validation of audio-visual mappings for sound synthesis. These methods could be applied to a wide range of contexts in order to inform the design of cognitively useful multi-modal interfaces and representation and rendering of multimodal data. Moreover this research contributes to the broader understanding of multimodal perception by gathering empirical evidence about the correspondence between auditory and visual feature dimensions and by investigating which factors affect the perceived congruency between aural and visual structures.
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Desenho e fisioterapia: a contribui??o do exerc?cio do desenho para o aprendizado da cinesiologiaDias, Josemar Blures de Souza 27 August 2015 (has links)
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Previous issue date: 2015-08-27 / This research is the result of interdisciplinary analysis between the design and Physiotherapy Sciences, using as parameter the intercession of graphic production to the scope of content learning experiences of Kinesiology discipline applied to Physiotherapy course, considering four main themes (myology , osteology, joint structure and movement). The study methodology was based on Action Research Method, by scientifically substantiate the master's degree to work in the field phase directly assisting the participants in the design of production, but without interfering with the student's graphic development. To complement the data collected, we used a structured questionnaire in eight closed questions answered at two different times, considering: The first five questions answered before the design exercise. The last three questions answered only after the completion of design exercises. Data collection was conducted in the months of September and October - 2014 considering holding eight meetings for Design of production. The activity included the participation of twenty-eight students who were in the second half of the Physical Therapy course of the School San Antonio - FSA, institution located in the city of Alagoinhas, Bahia. The analysis of the collected Drawings revealed the facts communication with the scientific reality discussed in kinesiology the conceptual direction of Sketching mode for production of the Drawings. Drawing exercise was efficient on deepening the relationship of visual learning and development of motor learning for the exercise of design built in the classroom. The appreciation of the responses contained in the questionnaire applied in the field found that participants felt unanimously that exercise design allowed them to learning experiences when working the contents of Kinesiology discipline. / Esta pesquisa ? o resultado da an?lise transdisciplinar entre as Ci?ncias do Desenho e da Fisioterapia, utilizando como par?metro de intercess?o a produ??o gr?fica para o alcance de experi?ncias de aprendizagem de conte?dos da disciplina de Cinesiologia aplicada ao curso de Fisioterapia, considerando quatro temas centrais (miologia, osteologia, estrutura articular e movimento). A metodologia do estudo baseou-se no M?todo Pesquisa-A??o, por fundamentar cientificamente o mestrando para atuar na fase de campo auxiliando diretamente os participantes na produ??o de Desenho, por?m, sem interferir no desenvolvimento gr?fico do estudante. Para a complementa??o dos dados coletados, utilizou-se um question?rio estruturado em oito quest?es fechadas, respondidas em dois momentos distintos, considerando: As cinco primeiras quest?es respondidas antes do in?cio do exerc?cio de Desenho. As tr?s ?ltimas quest?es respondidas somente ap?s a finaliza??o dos exerc?cios de Desenho. A coleta de dados foi realizada nos meses de Setembro e Outubro ? 2014, considerando a realiza??o de oito encontros para produ??o de Desenho. A atividade contou com a participa??o de vinte e oito estudantes que cursavam o segundo semestre do curso de Fisioterapia da Faculdade Santo Ant?nio ? FSA, institui??o situada na cidade de Alagoinhas-BA. As an?lises dos Desenhos coletados revelaram a comunica??o de fatos da realidade cient?fica discutida na Cinesiologia com a orienta??o conceitual da modalidade de Debuxo para a produ??o dos Desenhos. O exerc?cio de Desenho se mostrou eficiente diante a rela??o de aprofundamento do aprendizado visual, e desenvolvimento do aprendizado motor para o exerc?cio do Desenho constru?do em sala de aula. A aprecia??o das respostas contidas no question?rio aplicado em campo constatou que os participantes consideraram de forma un?nime que o exerc?cio de Desenho lhes possibilitou experi?ncias de aprendizagem ao trabalhar os conte?dos da disciplina de Cinesiologia.
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INVESTIGATING CREATIVE AND DESIGN-ORIENTED PRACTICES IN K-12 ENRICHMENT COURSESMehdi Ghahremani (9109535) 27 July 2020 (has links)
<p>This
thesis is an article-based (3-paper format) dissertation. In the first
article, the research
team adapted an input-process-outcome (IPO) model of
group-level processes in the classroom, as a theoretical framework, to examine
students’ experiences regarding pre-college engineering curricula, classroom
environments, and their experiences with the creative process in the two
engineering courses offered in a university-based summer enrichment program.
Applying provisional and open coding to semi-structured interview data from 16 participants, an Input-Process-Outcome Model of Collaborative Creativity (IPOCC model)
was developed. In this
study, I grouped our findings under Inputs, Group Processes, Outcomes, and
Mediating Factors. The IPOCC model expands the 4P model
of creativity to incorporate more collaborative contexts. According to the 4P
model, creativity can be viewed from four different perspectives: Person,
Process, Product, and Press. The IPOCC model suggests that in K-12
collaborative practice, creativity involves group-level considerations in
addition to individual-level components. The IPOCC model offer insights for
educators in terms of input components, group processes, and mediating factors
that can facilitate learners’ engagement in creative teamwork. Findings of this study indicated
that a combination of challenging tasks, open-ended problems, and student
teamwork provides a rich environment for learners’ engagement to think
creatively.</p>
<p>The
purpose of the second study was to systematically investigate how novice/K-12
students’ visual representation of design ideas has been operationalized,
measured, or assessed in the research literature. In the different phases of screening in this systematic review,
inclusion, exclusion, and quality criteria were applied. From an initial sample
of 958 articles, 40 studies were included in the final step of the coding
process and qualitative synthesis. Applying provisional and open coding, three
broad themes, and 23 characteristics were identified that have been used by
researchers to conceptualize sketching of ideas, in novice/K-12 design activities:
Communicating Ideas, Visual-Spatial Characteristics, and Design Creativity. We
propose this Three-pronged Design Sketching (3-pDS) framework to examine K-12
design sketches. </p>
In K-12 settings, one major
challenge of conducting research on the influence of engineering education
programs and curricula involves assessment. There is a need for developing
alternative, effective, and reliable assessment measures to evaluate students’
design activities. The third study aimed to address this need by developing the
idea-Sketching Early Engineering Design (i-SEED) Scale to assess pre-college
learners’ freehand sketches in response to a design task. Applying the
Three-pronged Design Sketching (3-pDS) as a theoretical framework, the purpose
of this study was to examine evidence of content validity, construct validity,
and internal consistency of the i-SEED Scale data. The data collection took
place in a residential summer enrichment program for students with gifts and
talents at a Midwestern university. Following different stages of
scale-development design, a sample of 113 design sketches were scored in this
study, and the scores were used to provide evidence of the validity of the data
for the i-SEED Scale. The sketches were generated by 120 middle- and
high-school students in a collaborative design-oriented course. Exploratory
factor analysis results supported a three-factor model for the i-SEED Scale,
including Visual-Spatial Characteristics, Design Creativity, and Communicating
Ideas.
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Contributions to unsupervised learning from massive high-dimensional data streams : structuring, hashing and clustering / Contributions à l'apprentissage non supervisé à partir de flux de données massives en grande dimension : structuration, hashing et clusteringMorvan, Anne 12 November 2018 (has links)
Cette thèse étudie deux tâches fondamentales d'apprentissage non supervisé: la recherche des plus proches voisins et le clustering de données massives en grande dimension pour respecter d'importantes contraintes de temps et d'espace.Tout d'abord, un nouveau cadre théorique permet de réduire le coût spatial et d'augmenter le débit de traitement du Cross-polytope LSH pour la recherche du plus proche voisin presque sans aucune perte de précision.Ensuite, une méthode est conçue pour apprendre en une seule passe sur des données en grande dimension des codes compacts binaires. En plus de garanties théoriques, la qualité des sketches obtenus est mesurée dans le cadre de la recherche approximative des plus proches voisins. Puis, un algorithme de clustering sans paramètre et efficace en terme de coût de stockage est développé en s'appuyant sur l'extraction d'un arbre couvrant minimum approché du graphe de dissimilarité compressé auquel des coupes bien choisies sont effectuées. / This thesis focuses on how to perform efficiently unsupervised machine learning such as the fundamentally linked nearest neighbor search and clustering task, under time and space constraints for high-dimensional datasets. First, a new theoretical framework reduces the space cost and increases the rate of flow of data-independent Cross-polytope LSH for the approximative nearest neighbor search with almost no loss of accuracy.Second, a novel streaming data-dependent method is designed to learn compact binary codes from high-dimensional data points in only one pass. Besides some theoretical guarantees, the quality of the obtained embeddings are accessed on the approximate nearest neighbors search task.Finally, a space-efficient parameter-free clustering algorithm is conceived, based on the recovery of an approximate Minimum Spanning Tree of the sketched data dissimilarity graph on which suitable cuts are performed.
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Plaggskissen som ett kommunikationsverktyg för produktutvecklingsprocessen inom modeföretag / The garment sketch as a communication tool for the product development process in fashion companiesAlm Brillantes, Olivia, Svartz, Helena January 2019 (has links)
En designer menar att kommunicera sina idéer genom illustrerande plaggskisser till andra involverade i företaget. Idéerna är vaga, detaljrika, provisoriska eller abstrakta. Att tolka någonting som saknar precision är en osäkerhet, dessutom kan feltolkningar av skisser skapa stora kommunikationsproblem inom ett designteam. Genom att utföra semistrukturerade intervjuer och deltagande observationer hos modeföretag i Sverige har kvalitativt material jämförts med den litteratur och de studier som finns om ämnet idag. Från de studier och artiklar som refereras till i detta arbetet har olika riktningar uppenbarats, som kan vara goda att undersöka i ämnet. Däribland behovet av att skapa meta-notationer, nämligen ett skriftligt system som diskuterar kommunikationen i designprocessen. Ett antal flödeskartor har även ritats upp, utifrån observationer av gruppdynamik, företagsstruktur, beteendemönster, samt intervjufrågor med olika roller i designteamen. / A designer believes that communicating their ideas through illustrative garment sketches to others involved in the company. The ideas are vague, detailed, provisional or abstract. Interpreting something that lacks precision is an uncertainty; furthermore, misinterpretation of sketches can create great communication problems with design teams. By conducting semi-structured interviews and having participatory observations at fashion companies in Sweden, qualitative material has been compared to the literature and studies available on the subject today. From the studies and articles referred to in this work, different directions have been revealed, which may be good to investigate on the subject. This includes the need to create meta-notations, namely a written system that discusses the communication in the design process. A number of flow charts have thus been drawn up, based on observations on tone, gestures and mimics, as well as interview questions with different roles in the design teams.
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