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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
451

Kindertivity: Usability and Communicability Strategies for Interactive Surfaces and Pre-Kindergarten Children

Nácher Soler, Vicente Ernesto 18 January 2020 (has links)
Tesis por compendio / [ES] La tecnología multi-táctil se ha convertido en una de las más emergentes tras experimentar un enorme crecimiento desde sus pasos iniciales en los años ochenta hasta su amplia aceptación y uso en la actualidad. Por una parte, la tecnología multi-táctil se basa en el estilo de interacción de manipulación directa el cual proporciona a los usuarios la ventaja de ver los objetos y las acciones de interés, sustituir comandos escritos por acciones de señalado y, además, permite la realización de acciones rápidas, reversibles e incrementales evitando el uso de instrucciones complejas. Por otra parte, diversos trabajos han evaluado las virtudes derivadas de utilizar conjuntamente la manipulación directa con el toque directo mostrando que es posible evitar los problemas inherentes a otras técnicas de interacción como el ratón y el teclado. Por lo tanto, aprovechando la interacción natural e intuitiva proporcionada por la tecnología multi-táctil, ésta parece una forma ideal para dar soporte a la creación de escenarios educativos dirigidos a niños en edad preescolar. Sin embargo, a pesar de la existencia de diversos estudios que evalúan la idoneidad de utilizar el estilo de interacción de manipulación directa, existe una falta de trabajos abordando el uso dispositivos basados en superficies táctiles con niños de una temprana edad. Asimismo, en la actualidad existe una creciente tendencia a diseñar aplicaciones educativas y lúdicas dirigidas a niños en edad preescolar utilizando dispositivos multi-táctiles como los teléfonos inteligentes o las tabletas. Además, diversos informes señalan que los niños son usuarios frecuentes de este tipo de dispositivos y los utilizan incluso antes de ser capaces de hablar. Sin embargo, a pesar de este crecimiento en el uso de la tecnología multi-táctil y su aparente idoneidad para ser utilizado en el desarrollo de aplicaciones educativas para niños en edad preescolar, no existen unas interacciones universales y estandarizadas para preescolares a la hora de utilizar dispositivos táctiles ya que habitualmente sólo se utilizan dos gestos básicos (básicamente, el toque con un dedo para seleccionar y el arrastre con un dedo para el movimiento). Por lo tanto, existe una clara necesidad de llevar a cabo estudios empíricos para contribuir y avanzar en el diseño de aplicaciones que den un soporte adecuado y encaje con las habilidades de los niños en su temprano desarrollo. Por tanto, esta tesis propone, diseña y evalúa diversas estrategias de usabilidad y comunicabilidad adaptadas a los niños en edad preescolar para establecer la base para el diseño y desarrollo de futuras aplicaciones basadas en dispositivos táctiles dirigidas a preescolares. Estas estrategias llevarán a la adecuada definición de guías de diseño que permitirán a los niños aprovechar al máximo la tecnología multi-táctil, harán posible el desarrollo de nuevas y atractivas aplicaciones y, eventualmente, también podrán ayudar al desarrollo cognitivo y motor de los niños. / [CA] La tecnologia multi-tàctil s'ha convertit en una de les més emergents després d'experimentar un enorme creixement des dels seus passos inicials als anys vuitanta fins l'actualitat on es àmpliament acceptada i utilitzada. D'una banda, la tecnologia multi-tàctil es basa en l'estil d'interacció de manipulació directa, el qual proporciona als usuaris l'avantatge de veure els objectes i les accions d'interès, substituir comandos escrits per accions d'assenyalament i, a més, permet la realització d'accions, ràpides, reversibles i incrementals evitant l'ús d'instruccions complexes. D'altra banda, diversos treballs han avaluat les virtuts derivades d'utilitzar conjuntament la manipulació directa amb el toc directe mostrant que és possible evitar els problemes inherents a altres tècniques d'interacció com el ratolí i el teclat. Per tant, aprofitant la interacció natural i intuïtiva proporcionada per la tecnologia multi-tàctil, aquesta sembla una forma ideal per donar suport a la creació d'escenaris educatius per a xiquets en edat preescolar. No obstant això, malgrat l'existència de diversos estudis que avaluen la idoneïtat d'utilitzar l'estil d'interacció de manipulació directa, existeix una manca de treballs abordant l'ús de dispositius basats en superfícies tàctils amb xiquets d'edat primerenca. Així mateix, en l'actualitat existeix una creixent tendència a dissenyar aplicacions educatives i lúdiques dirigides a xiquets en edat preescolar utilitzant dispositius tàctils com els telèfons intel¿ligents o les tauletes. A més, diversos informes assenyalen que els xiquets són usuaris freqüents d'aquests tipus de dispositius i els utilitzen fins i tot abans de ser capaços de parlar. Malgrat aquest creixement en l'ús de la tecnologia multi-tàctil i la seua aparent idoneïtat per a ser utilitzada en el desenvolupament d'aplicacions educatives per a xiquets en edat preescolar, no existeixen unes interaccions universals i estandarditzades per a preescolars a l'hora d'utilitzar dispositius tàctils ja que habitualment només s'utilitzen dos gestos bàsics (bàsicament, el toc amb un dit per a seleccionar i l'arrossegament amb un dit per al moviment). Per tant, hi ha una clara necessitat de dur a terme estudis empírics per a contribuir i avançar en el disseny d'aplicacions que donen un suport adequat i s'ajusten amb les habilitats dels xiquets en el seu primerenc desenvolupament. Per tant, la tesi proposa, dissenya i avalua diverses estratègies de usabilitat i comunicabilitat adaptades als xiquets en edat preescolar per tal d'establir la base per al disseny i desenvolupament de futures aplicacions basades en dispositius tàctils dirigides a preescolars. Aquestes estratègies portaran a l'adequada definició de guies de disseny que permetran als xiquets aprofitar al màxim la tecnologia multi-tàctil, faran possible el desenvolupament de noves i atractives aplicacions i, eventualment, podran també ajudar al desenvolupament cognitiu i motor dels xiquets. / [EN] Multi-touch technology has become one of the most emergent technologies and has had an enormous growth since its initial steps in the eighties to be widespread accepted and used in the present. On the one hand, multi-touch technology relies on the direct manipulation interaction style which gives users the advantage to view the objects and actions of interest, replace typed commands by pointing actions and to perform rapid, reversible and incremental actions avoiding using complex instructions. On the other hand, several works have evaluated the virtues when joining direct manipulation with direct-touching showing that it solves the problems inherent in other interaction devices, such as those involving mouse or keyboard. Hence, taking advantage of the intuitive and natural interaction provided by multi-touch technology it seems an ideal way to support educational scenarios targeted to kindergarten children. Although several works have assessed the suitability of using the direct manipulation style with children, there is a lack of works addressing the use of touchscreen devices by this specific type of users. Moreover, there is a growing trend of designing educational and playful applications targeted to kindergarten children based on touchscreen devices such as smartphones and tablets. In addition, several reports point out that children use touchscreen devices even before they are able to speak and they are frequent users of devices such as smartphones and tablets. However, despite this growth in the use of multi-touch technology by children and its apparent suitability to be used to develop applications targeted to young children, there is a lack of standardized and universally accepted interactions for young children when using touchscreen devices since only two basic gestures are commonly used (basically, consisting of only one-finger touch for selection and one-finger drag for movement). Hence, there is a need of carrying out empirical studies to help and advance in the design of applications that adequately support and fit with children's development and skills. Therefore, this thesis proposes, designs and evaluates several usability and communicability strategies tailored to children in their early development stage to establish the design and development of future applications targeted to kindergarten children. These strategies will lead to define appropriate design strategies that enable infants to take full advantage of multi-touch technology, would make it possible to develop attractive new applications and, eventually, could also aid children's cognitive and motor development. / Nácher Soler, VE. (2019). Kindertivity: Usability and Communicability Strategies for Interactive Surfaces and Pre-Kindergarten Children [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/116833 / Compendio
452

Serial and Parallel Elastic Cable Driven Actuator (SPECA) to Achieve Efficient and Safe Human Robot Physical Interaction

Al-Ani, Al-Muthanna 01 January 2024 (has links) (PDF)
In this thesis, design, integration and validation of Serial and Parallel Elastic Cable Actuator (SPECA) is presented with an aim to enhance human-device interaction in cable-driven systems of wearable robots and to optimize actuator force and power delivery to the user. Adding springs in series and in parallel to the cables acted on the mechanical joint for motion or force control have been shown individually to reduce mechanical power consumption and therefore electrical power consumption. SPECA combines both serial elastic (SE) and parallel elastic (PE) components to explore the compounded effects on a dual cable driven system controlled by a single actuator. A bi-articulating winch attached to the actuator allows control of two cables to achieve a bidirectional control of a revolute joint. Expanding the control of the single actuator, the dual cables route to a mechanical clutch that can engage up to two external winches, or four cables, simultaneously. SPECA is built as an isolated system with only the two winches of the clutch leading to end effectors creating a design capable of being integrated into many cable driven systems. A Simulink model is developed of a simple two degree of freedom (DOF) system to confirm that SE and PE elements not only increase the effective range of a system but lower the mechanical power. SPECA undergoes static and dynamic experiments to explore SE and PE in an applied system confirming the conclusions of the model along with recommendations based on observed characteristics from the experiments. SPECA serves as an exploratory and modular proof of concept for the integration of SE and PE components into many cable driven systems.
453

En jämförelse mellan fjärranalystekniker och vågbojar för mätning av oceanografiska parametrar i svenska vatten

Bennich, David, Bredberg, William, Olsson, Jimmy, Rulewski Stenberg, Louis, Smith, Malin, Söderqvist, Johnny January 2017 (has links)
För övervakning av svenska vatten krävs noggranna mätningar av oceanografiska parametrar såsom våghöjd, vågriktning, ytvattentemperatur och ytströmmar. Mätdata för parametrarna samlas in av Sveriges Meteorologiska och Hydrologiska Institut (SMHI) och används till prognoser, sjöfart samt forskning. I denna studie undersöktes möjligheten att ersätta eller komplettera vågbojarna av modellen Directional Waverider MkIII som SMHI använder idag, med ny kommersiellt tillgänglig fjärranalysteknik. Projektet begränsades till att studera två högfrekvens-radartekniker och en X-bandradar. Studien är platsspecifik och utreder kvalitetsmässiga, ekonomiska och miljömässiga för- och nackdelar med de utvalda radarteknikerna i relation till vågbojarna. En litteraturstudie och modellering av data över parametrar som påverkar radarteknikernas räckvidd och datatillgänglighet genomfördes. Ur modelleringen drogs slutsatsen att det är möjligt att erhålla likvärdig datatillgänglighet med vågradar som med vågboj. Vidare modellering ledde till slutsatsen att radarteknikerna begränsas till ungefär hälften av sin optimala räckvidd i Östersjön på grund av den låga salthalten, och därför är Sveriges västkust bättre lämpad för placering av radarteknik. Undersökning av isbildning i havsvatten, som kan begränsa radarteknikernas räckvidd, ledde till slutsatsen att Sveriges västkust också är att föredra utifrån detta perspektiv. Med anledning av radarteknikers möjlighet att utföra mätningar över större områden, finner studien att det finns goda grunder för att motivera en ersättning eller komplettering av vågbojarna med modern radarteknik. Vidare talar radarteknikernas goda anpassningsförmåga, lägre inverkan på miljön och enklare underhållskrav jämfört med vågbojarna till dess fördel. Att övergå till radarteknik medför däremot högre installations- och driftkostnader i jämförelse med vågbojar.
454

Fourier and Variational Based Approaches for Fingerprint Segmentation

Hoang Thai, Duy 28 January 2015 (has links)
No description available.
455

基於方向性邊緣特徵之即時物件偵測與追蹤 / Real-Time Object Detection and Tracking using Directional Edge Maps

王財得, Wang, Tsai-Te Unknown Date (has links)
在電腦視覺的研究之中,有關物件的偵測與追蹤應用在速度及可靠性上的追求一直是相當具有挑戰性的問題,而現階段發展以視覺為基礎互動式的應用,所使用到技術諸如:類神經網路、SVM及貝氏網路等。 本論文中我們持續深入此領域,並提出及發展一個方向性邊緣特徵集(DEM)與修正後的AdaBoost訓練演算法相互結合,期能有效提高物件偵測與識別的速度及準確性,在實際驗證中,我們將之應用於多種角度之人臉偵測,以及臉部表情識別等兩個主要問題之上;在人臉偵測的應用中,我們使用CMU的臉部資料庫並與Viola & Jones方法進行分析比較,在準確率上,我們的方法擁有79% 的recall及90% 的precision,而Viola & ones的方法則分別為81%及77%;在運算速度上,同樣處理512x384的影像,相較於Viola & Jones需時132ms,我們提出的方法則有較佳的82ms。 此外,於表情識別的應用中,我們結合運用Component-based及Action-unit model 兩種方法。前者的優勢在於提供臉部細節特徵的定位及追蹤變化,後者主要功用則為進行情緒表情的分類。我們對於四種不同情緒表情的辨識準確度如下:高興(83.6%)、傷心(72.7%)、驚訝(80%) 、生氣(78.1%)。在實驗中,可以發現生氣及傷心兩種情緒較難區分,而高興與驚訝則較易識別。 / Rapid and robust detection and tracking of objects is a challenging problem in computer vision research. Techniques such as artificial neural networks, support vector machine and Bayesian networks have been developed to enable interactive vision-based applications. In this thesis, we tackle this issue by devising a novel feature descriptor named directional edge maps (DEM). When combined with a modified AdaBoost training algorithm, the proposed descriptor can produce effective results in many object detection and recognition tasks. We have applied the newly developed method to two important object recognition problems, namely, face detection and facial expression recognition. The DEM-based methodology conceived in this thesis is capable of detecting faces of multiple views. To test the efficacy of our face detection mechanism, we have performed a comparative analysis with the Viola and Jones algorithm using Carnegie Mellon University face database. The recall and precision using our approach is 79% and 90%, respectively, compared to 81% and 77% using Viola and Jones algorithm. Our algorithm is also more efficient, requiring only 82 ms (compared to 132 ms by Viola and Jones) for processing a 512x384 image. To achieve robust facial expression recognition, we have combined component-based methods and action-unit model-based approaches. The component-based method is mainly utilized to locate important facial features and track their deformations. Action-unit model-based approach is then employed to carry out expression recognition. The accuracy of classifying different emotion type is as follows: happiness 83.6%, sadness 72.7%, surprise 80%, and anger 78.1%. It turns out that anger and sadness are more difficult to distinguish, whereas happiness and surprise expression have higher recognition rates.
456

台灣銀行業效率與生產力分析─方向距離函數之應用 / Efficiency and productivity change of Taiwanese banking Industry- An application of directional distance function

范雅鈞, Fan, Ya Jyun Unknown Date (has links)
本文利用可以同時捕捉到銀行增加意欲產出、減少投入與減少非意欲產出的方向距離函數,評估台灣銀行業與個別銀行在民國93年至97年的無效率值與生產力變化。設定逾期放款為銀行生產放款時的非意欲產出,以考量銀行的放款品質,也考慮到銀行都會付出成本來提供服務給存戶,因此以交易性存款作為銀行提供服務的替代變數,使銀行的服務包含在效率評估內,並以固定的方向向量作為無效率值加總的基礎,來衡量台灣整體銀行業的無效率。實證結果是台灣銀行業的無效率值隨著雙卡風暴的遠去,有逐年遞減的趨勢,生產力的變化則是退步的情況較多。 / In this paper we estimate Taiwanese banks’ efficiency and productivity change during 2004-2008. The estimates are derived from the directional distance function. We treat non-performing loans as an undesirable output arising from the production of loans to measure the quality of loans. Considering every bank would make costs to serve customers, we choose transaction deposits as an alternative variable to capture the service provided by banks. The way we set the directional vector allows the aggregation of individual bank inefficiency and productivity change to the industry level. Our findings indicate that inefficiencies of Taiwanese banking industry were decreasing after the over of credit and cash card debts. And Taiwanese banking industry experienced productivity regress during this period.
457

運用隨機方向距離函數法探討非意欲產出對銀行經營效率之影響 / Do Undesirables Matter on the Examination of Banking Efficiency Using Stochastic Directional Distance Functions

鍾銘泰, Chung, Ming Tai Unknown Date (has links)
本文採取隨機方向距離函數方法,探討制度變革前、後(第一次金融改革)對台灣銀行業技術效率的影響。資料期間涵蓋1999年至2012年。相較傳統Shephard距離函數,隨機方向距離函數方法最大優點係可同時考量增加意欲產出、減少投入與非意欲產出。本文依循Koutsomanoli-Filippaki et al. (2009a) 模型,並納入考慮非意欲產出。本文採取隨機邊界法進行實證估計,以最大概似法估計方向距離函數,依據Battese and Coelli (1995)的模型將環境變數納入實證模型 (主要模型),並考量未包含環境變數之模型,與主要模型比較。此外,為凸顯非意欲產出之重要性,本文亦估計未考慮非意欲產出之模型以及傳統距離函數,以茲比較。 實證結果顯示,考慮非意欲產出與環境變數的主要模型,其估計結果相較其他模型之無效率明顯高估。2002年以前,技術無效率逐漸攀升。一次金改期間,技術無效率明顯下降,證明制度變革下,銀行效率獲得改善。惟2004年後反轉向上,尤其在雙卡風暴與次貸風暴期間,技術無效率明顯惡化。此外,本文將資料分群進行分析,發現公營銀行或是金控銀行較有效率。 / This paper aims to gain further insights into whether the policy of First Financial Restructuring (FFR) does improve the technical efficiency of banks in Taiwan during the period 1999-2012 by using the directional technology distance function (DDF). Compared to the conventional distance function, DDF simultaneously allows for the expansion of the desirables and the contraction of the undesirables. We follow Koutsomanoli-Filippaki et al. (2009a), and differing from them, we include undesirable outputs in DDF to depict a bank’s true production activities. We find on average that the banks have a lower technical inefficiency with the main model compared to the other models. However, prior to 2002, the technical inefficiency exhibits a gradual upward trend and then posts a downward trend during the FFR period. These results suggest that the improved efficiency in the FFR period is possibly due to enhanced banking and benefits obtained from compliance with FFR. After the FFR period, the inefficiency scores deteriorate sharply, especially during the “credit card and cash card crisis” in 2006 and “the subprime mortgage crisis” in 2008. Public banks are more efficient than private banks. Banks belonging to a financial holding company (FHC) may operate more efficiently than those belonging to a non-FHC.
458

Developing a theory of psychopathological perfectionism within a cognitive behavioural framework

Baker, David January 2012 (has links)
Background: Psychological perfectionism, from a clinical perspective, started to be a topic of interest for cognitive behavioural clinicians at the beginning of the 1950s. Whilst many studies have identified perfectionism as a pivotal motivator in different conditions of neurosis, the exact nature of its interactions remains unclear. In the research community there is still a debate as to whether there is such a thing as good perfectionism, and there remains no consensual theory of psychopathological perfectionism. Aims: The aim of the study was to investigate why the nature of the phenomena remains a contentious issue, and to develop a robust theory of psychopathological perfectionism, within a cognitive behavioural framework, which will find general acceptance. From the literature review this appears to be the first qualitative study to develop such a theory. Method: Substantive grounded theory was developed within a framework of methodical hermeneutics which, it is argued, is capable of generating formative theory. 20 volunteers who came forward in response to advertisements became participants in semi-structured interviews using a post classic qualitative methodology, from which emerging data became the basis of categories leading to the development of the theory, and functions of the phenomena. Results and Conclusions: The study sets out reasons why there remains an impasse amongst researchers and clinicians about the condition of psychopathological perfectionism. A parsimonious theory of pathological perfectionism has been developed, the constructs of which are just necessary and sufficient to describe the condition. The developed theory makes a contribution to theories proposed prior to 1990 and to contemporary research. However as with all theories it is necessarily provisional, so that its usefulness is in need of further research and development. Psychopathological perfectionism has only two constructs, namely a demand to achieve perfectionism in at least one idiosyncratic sphere, which is in response to a core schema of conditional worth. A number of symptoms or functions of psychopathological perfectionism have also been identified, and there are suggestions as to how the condition develops and is maintained to the detriment of the sufferer. The study synthesizes over fifty years of theory and research into the phenomena. The developed theory and its symptoms or functions have important implications for clinical interventions, training, and for further psychological and psychosocial research. These implications are discussed.
459

Essays on multivariate volatility and dependence models for financial time series

Noureldin, Diaa January 2011 (has links)
This thesis investigates the modelling and forecasting of multivariate volatility and dependence in financial time series. The first paper proposes a new model for forecasting changes in the term structure (TS) of interest rates. Using the level, slope and curvature factors of the dynamic Nelson-Siegel model, we build a time-varying copula model for the factor dynamics allowing for departure from the normality assumption typically adopted in TS models. To induce relative immunity to structural breaks, we model and forecast the factor changes and not the factor levels. Using US Treasury yields for the period 1986:3-2010:12, our in-sample analysis indicates model stability and we show statistically significant gains due to allowing for a time-varying dependence structure which permits joint extreme factor movements. Our out-of-sample analysis indicates the model's superior ability to forecast the conditional mean in terms of root mean square error reductions and directional forecast accuracy. The forecast gains are stronger during the recent financial crisis. We also conduct out-of-sample model evaluation based on conditional density forecasts. The second paper introduces a new class of multivariate volatility models that utilizes high-frequency data. We discuss the models' dynamics and highlight their differences from multivariate GARCH models. We also discuss their covariance targeting specification and provide closed-form formulas for multi-step forecasts. Estimation and inference strategies are outlined. Empirical results suggest that the HEAVY model outperforms the multivariate GARCH model out-of-sample, with the gains being particularly significant at short forecast horizons. Forecast gains are obtained for both forecast variances and correlations. The third paper introduces a new class of multivariate volatility models which is easy to estimate using covariance targeting. The key idea is to rotate the returns and then fit them using a BEKK model for the conditional covariance with the identity matrix as the covariance target. The extension to DCC type models is given, enriching this class. We focus primarily on diagonal BEKK and DCC models, and a related parameterisation which imposes common persistence on all elements of the conditional covariance matrix. Inference for these models is computationally attractive, and the asymptotics is standard. The techniques are illustrated using recent data on the S&P 500 ETF and some DJIA stocks, including comparisons to the related orthogonal GARCH models.
460

Violence conjugale et détresse psychologique chez les jeunes couples : analyse de l'effet modérateur du soutien social

Fortin, Isabel 08 1900 (has links)
Les jeunes adultes sont plus susceptibles de subir de la violence conjugale que les adultes plus âgés. Toutefois, l'effet de se confier à propos de la violence subie sur la santé mentale est peu connu. L'objectif de cette étude est d'explorer les liens entre la violence conjugale, le soutien social et la détresse psychologique selon le sexe dans un échantillon de 233 jeunes couples. Les résultats indiquent que, pour les femmes, la fréquence de la violence psychologique subie, mais pas celle de la violence physique, était positivement associée à la détresse psychologique. Pour ces femmes, recourir à un plus grand nombre de confidents diminue la force de la relation entre la violence et de leur niveau de détresse psychologique. Pour les hommes, les fréquences de la violence physique et psychologique subies étaient positivement liées à la détresse psychologique, mais contrairement aux femmes, plus ils se sont confiés à propos de la violence qu'ils ont subi, plus leur niveau de détresse est élevé. / Young adults are more likely to experience intimate partner violence (IPV) than older adults but little is known about the effect of confiding to others about the sustained violence on their mental health. The objective of this study was to explore the links between IPV, help-seeking and psychological distress by gender in a sample of 233 young couples. Our findings indicate that for women, the frequency of sustained psychological violence, but not of physical violence, was positively associated to psychological distress and that for these women, seeking help from a greater number of confidents decreased the strength of the association between violence and their level of psychological distress. Secondly, for men, the frequency of physical and psychological violence were both positively linked to psychological distress but unlike women, the more people they talked to about the violence they have sustained, the greater their level of distress was.

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