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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.
51

Matching Methods for Information Sharingwith Supply Chain Context / En matchning av metoder för informationsdelning med distributionskedjors kontext

HÅKANSSON, MICHAEL January 2016 (has links)
The productivity and competitiveness of companies fundamentally depend on their ability to handle information. With the available technology, the opportunities to collect and utilise information are better than ever. One of the industries that has proven to benefit significantly from analysing large quantities of information is the retail industry. However, before information can be analysed it has to be obtained. This often means that information has to flow between members in a supply chain. The purpose of this study was to investigate which methods that are suitable for sharing information in different contexts between suppliers and retailers. The research was conducted as a case study within the Swedish sporting goods industry, where the information sharing relationship between one supplier and seven of its customers was investigated. The studied methods for information sharing were manual document handling, web portals and through a third-party EDI service provider. The third-party EDI solution benefits both parties. However, this method is not always applicable. If resources are scarce for both communicating parties and no technological solution for information sharing is in place, the manual document handling method is a suitable short-term solution. If one party with lots of resources frequently share information with parties that cannot afford to invest in technological information sharing solutions, a portal can be a suitable compromise to let the company that invests in the portal gain efficiency benefits while the other parties continue to manually provide information. / Ett företags produktivitet och konkurrenskraft beror på dess förmåga att hantera information. Med den teknik som finns tillgänglig är möjligheterna att samla in och behandla information bättre än någonsin. En av de branscher som har visat sig ha stor nytta av att analysera stora mängder av information är detaljhandeln. Hur som helst måste informationen tas emot innan den kan analyseras. Detta innebär ofta att informationen måste flöda mellan medlemmar i en distributionskedja. Syftet med denna studie var att undersöka vilka metoder som är lämpliga för att dela information mellan leverantörer och återförsäljare. Undersökningen genomfördes som en fallstudie inom den svenska sportvaruindustrin, där informationsdelningsförhållandet mellan en leverantör och sju av dess kunder undersöktes. De studerade metoderna för informationsdelning var manuell dokumenthantering, webbportaler och genom en tredjeparts EDI-tjänst. EDI-lösningen gynnar båda parter, men är inte alltid tillämplig. Om resurserna är knappa för båda kommunicerande parter och ingen teknisk lösning för att dela information finns på plats är den manuella metoden en lämplig lösning på kort sikt. Om en part med stora resurser ofta delar information med parter som inte har möjlighet att investera i informationsdelningslösningar kan en portal vara en lämplig kompromiss. Den lösningen ger ffektivitetsvinster till företaget som investerar i portalen medan de andra parterna kan fortsätta att manuellt tillhandahålla information.
52

Extraction and integration of Web query interfaces

Kabisch, Thomas 20 October 2011 (has links)
Diese Arbeit fokussiert auf die Integration von Web Anfrageschnittstellen (Web Formularen). Wir identifizieren mehrere Schritte für den Integrationsprozess: Im ersten Schritt werden unbekannte Anfrageschnittstellen auf ihre Anwendungsdomäne hin analysiert. Im zweiten Schritt werden die Anfrageschnittstellen in ein maschinenlesbares Format transformiert (Extraktion). Im dritten Schritt werden Paare semantisch gleicher Elemente zwischen den verschiedenen zu integrierenden Anfragesschnittstellen identifiziert (Matching). Diese Schritte bilden die Grundlage, um Systeme, die eine integrierte Sicht auf die verschiedenen Datenquellen bieten, aufsetzen zu können. Diese Arbeit beschreibt neuartige Lösungen für alle drei der genannten Schritte. Der erste zentrale Beitrag ist ein Exktraktionsalgorithmus, der eine kleine Zahl von Designregeln dazu benutzt, um Schemabäume abzuleiten. Gegenüber früheren Lösungen, welche in der Regel lediglich eine flache Schemarepräsentation anbieten, ist der Schemabaum semantisch reichhaltiger, da er zusätzlich zu den Elementen auch Strukturinformationen abbildet. Der Extraktionsalgorithmus erreicht eine verbesserte Qualität der Element-Extraktion verglichen mit Vergängermethoden. Der zweite Beitrag der Arbeit ist die Entwicklung einer neuen Matching-Methode. Hierbei ermöglicht die Repräsentation der Schnittstellen als Schemabäume eine Verbesserung vorheriger Methoden, indem auch strukturelle Aspekte in den Matching-Algorithmus einfließen. Zusätzlich wird eine globale Optimierung durchgeführt, welche auf der Theorie der bipartiten Graphen aufbaut. Als dritten Beitrag entwickelt die Arbeit einen Algorithms für eine Klassifikation von Schnittstellen nach Anwendungsdomänen auf Basis der Schemabäume und den abgeleiteten Matches. Zusätzlich wird das System VisQI vorgestellt, welches die entwickelten Algorithmen implementiert und eine komfortable graphische Oberfläche für die Unterstützung des Integrationsprozesses bietet. / This thesis focuses on the integration of Web query interfaces. We model the integration process in several steps: First, unknown interfaces have to be classified with respect to their application domain (classification); only then a domain-wise treatment is possible. Second, interfaces must be transformed into a machine readable format (extraction) to allow their automated analysis. Third, as a pre-requisite to integration across databases, pairs of semantically similar elements among multiple interfaces need to be identified (matching). Only if all these tasks have been solved, systems that provide an integrated view to several data sources can be set up. This thesis presents new algorithms for each of these steps. We developed a novel extraction algorithm that exploits a small set of commonsense design rules to derive a hierarchical schema for query interfaces. In contrast to prior solutions that use mainly flat schema representations, the hierarchical schema better represents the structure of the interfaces, leading to better accuracy of the integration step. Next, we describe a multi-step matching method for query interfaces which builds on the hierarchical schema representation. It uses methods from the theory of bipartite graphs to globally optimize the matching result. As a third contribution, we present a new method for the domain classification problem of unknown interfaces that, for the first time, combines lexical and structural properties of schemas. All our new methods have been evaluated on real-life datasets and perform superior to previous works in their respective fields. Additionally, we present the system VisQI that implements all introduced algorithmic steps and provides a comfortable graphical user interface to support the integration process.
53

A Study on Social Influence Network in Consensus Group Judgment: Application of Information Integration Theory

Chen, Bi-Chen 24 July 2006 (has links)
¡§Individual¡¨is the basic analytic unit in a pluralistic society. Especially, phenomenon of public affairs is essence of the problem and is based on individual cognition, hidden in group behavior. The individual cognition forms group judgment and interpersonal influence in the group. This interpersonal influence process may simplify as the power relations between group members, the communication network and the interaction form in the group, and the opinion relations within the group (French, 1956). The conflict is the essential situation of interpersonal influence and also is one kind of relational form and phenomenon for group judgment. Therefore, it is necessary to understand the interpersonal influence and conduct interpersonal mutual cooperation in the public affairs area. The group decision-making (or judgment) can be explored based on observable individual preference and group decision-making. That can infer unobservable interpersonal influence. This interpersonal influence process transforms the individual judgment into the group decision-making. There are two stages in interpersonal influence process, including opinion formation for individual members, and compromise among group members. Namely, the individual might revise his or her preference voluntarily. The group integrates the revised members¡¦ judgments into group decision-making. That is, the group process resembles the process which individual integrates multi-cues like information integration theory (IIT) (Friedkin, 2005; Sniezek et al., 1989). The average cognitive algebra pattern in IIT may measure the interpersonal influence effectively. The theories of group decision-making are still insufficient. For example, social power theory and social comparison theory explain the concept of choice shift, but not positivism. Social decision scheme (SDS) employs decision scheme to predict the group decision-making, but it is insufficient for explaining the group decision-making process. Although social dilemma explores both individual level and group level, it cannot provide the weighting method. Cognitive conflict paradigm (CCP) discusses judgment policy shift, but preference shift is still not mentioned. Although CCP focuses on interpersonal learning, it does not propose how to weight interpersonal influence. The functional measurement theory in IIT may supplement insufficiencies in these theories.. The research utilizes the concept and the method of IIT, which prodivides experimental validity for explaining the complex interpersonal influence process by using social weight. This research uses budget allocation as discussion cases. Interpersonal conflicts are divided by the cognitive conflict and the interest conflict. By using social judgment theory (SJT), this research can analyze cognitive difference in the case of cognitive conflict. Besides, using quasi-experimental procedure in IIT, the findings of this research include: 1. In the group process, group members¡¦ judgments are integrated to group decision-making based on unequal-weight rule mostly. Members¡¦ social weights are different and depend on the level of members¡¦ preferences. 2. The members in different groups have the same preferences initially. Although social weights of these members are not significant difference in statistic, these members still appear the differences between individuals. 3. In cognitive conflict case, the group consensus is not consistently accompanied by cognitive consensus. 4. The group influence results from normative social influence, rather than from informational social influence. 5. It shows that there is negative correlation between social weight and normative effect. Besides, social weight and comprise degree also show negative.correlation 6. The cognitive feedback and the outcome feedback don¡¦t affect decision-making result. 7. The relationship between social weight and the degree of satisfaction is not supported. The social weight and the fairness of decision-making process show significant correlation 8. The subjects¡¦ decision-making performances in the study don¡¦t show significant difference
54

The judgment study for attributes and problems of place marketing of Kaohsiung in pluralistic societies¡ÐThe applications and comparisons of multiple-attribute weight measurement methods.

Dai, Ya-ming 06 July 2007 (has links)
In the current pluralistic societies, public policy-makings had to take into account various stakeholders as well as the social values. The research, based on the integrated public affairs management¡]PAM¡^ framework (Wang et al., 2004a) and place marketing strategy (Kotler, 1999), defined the applicable operational variables which includes three major factors of economical, social and political, and government, and nine derivative attributes, two situations of direct three-links between Taiwan and Mainland China, and status quo are used as the scenario. Altogether they will influence the stakeholders as decision-makers while deciding if they should invest, live, or work in Kaohsiung. For research design, we employed three major multiple-attribute theories or methods for individual stakeholders¡¦information processing and integration, Information Integration Theory¡]IIT¡^, Analytical Hierarchy Process¡]AHP¡^, Simple Multi-Attribute Rating Technique¡]SMART¡^, and Rating. In particular, the way the information is integrated cognitively is empirically examined instead of assumed with the averaging model of the IIT (Anderson, 1991a), and the scale values (equivalent to the utility component in MAUT or AHP) and the weights are concurrently separated and measured as results of the examination. Such separation rendered measurement of the psychological weights with theoretical validity possible, and could be used as the standard so that weights measured with the other three methods are evaluated and compared. Findings of the research are as follow, in the aspect of multiple-attribute weight measurement methods applied in the place marketing of Kaohsiung¡G 1. Among the three major factors, the most important is ¡§economic development¡¨, the second is ¡§government function¡¨, and then the third is ¡§social and political development¡¨. 2. For economic development, under the situation of maintain status quo, the most crucial derivative attribute is¡§ the level of economic globalization of Kaohsiung¡¨. The second one is ¡§the industrial structure of Kaohsiung city¡¨. The last one is ¡§the competitiveness of Kaohsiung Port and Airport project¡¨¡FUnder the situation of opening for three direct-links, the most crucial derivative attribute is still ¡§the level of economic globalization of Kaohsiung¡¨. The second one is ¡§the competitiveness of Kaohsiung Port and Airport project¡¨. The last one is ¡§the industrial structure of Kaohsiung city¡¨. 3. For the factor of social and political development, the most important attribute is ¡§the level of citizen participation in public affairs and the extent they influence public policies¡¨, the second is ¡§the public values and culture¡¨, the last is ¡§the operational mechanism of politics and election¡¨. 4. As for government function, the most essential attribute is ¡§the provision of public infrastructures¡¨. The second is ¡§the elected officials¡¦ perception of place marketing and capabilities of policy planning¡¨. The third is¡§the career officials¡¦ identifications for the elected officials¡¦ ambitions and abilities to carry out the place marketing policies¡¨. 5. The second group examinees think that direct-links has positive effects on the developments of Kaohsiung and most of them approve of the policy of three direct-links¡Fthe first group examinees have diverse opinions on it. 6. Based on PAM framework, we will sum up the problems of place marketing of Kaohsiung and brings out policy suggestions for Kaohsiung city. In the aspect of Multiple-attribute weight measurement methods theory¡G 1. Take the weight parameters derived from IIT¡¦s averaging model as the standard, weights from rating¡BAHP and SMART are all theoretically valid. The theoretical validity of rating outperforms that of AHP, AHP outperforms that of SMART. Among the convergence validity or consistence of four methods, between rating and AHP with IIT¡¦s averaging model fit better in convergence validity, between SMART and IIT¡¦s averaging model don¡¦t. 2. All three models had fairly high predictability and notable for subjects¡¦ holistic judgments. The predictability of IIT is the a little bit higher than SMART, the third one is AHP, and the last one is rating. 3. For convergence, measured with accumulative weights derived from subjects selected 15-20 examinees randomly, IIT was better than SMART, and SMART was better than AHP. 4. In terms of perceived performance, degree of operational easiness and fondness, the three models are not significantly different. As for the degree of confidence, IIT outperformed AHP, and AHP outperformed SMART.
55

Ein Integrations- und Darstellungsmodell für verteilte und heterogene kontextbezogene Informationen / An Integration and Representation Model for Distributed and Heterogeneous Contextual Information

Goslar, Kevin 07 February 2007 (has links) (PDF)
Die "Kontextsensitivität" genannte systematische Berücksichtigung von Umweltinformationen durch Anwendungssysteme kann als Querschnittsfunktion im betrieblichen Umfeld in vielen Bereichen einen Nutzen stiften. Wirklich praxistaugliche kontextsensitive Anwendungssysteme, die sich analog zu einem mitdenkenden menschlichen Assistenten harmonisch in die ablaufenden Vorgänge in der Realwelt einbringen, haben einen enormen Bedarf nach umfassenden, d.h. diverse Aspekte der Realwelt beschreibenden Kontextinformationen, die jedoch prinzipbedingt verteilt in verschiedenen Datenquellen, etwa Kontexterfassungssystemen, Endgeräten sowie prinzipiell auch in beliebigen anderen, z.T. bereits existierenden Anwendungen entstehen. Ziel dieser Arbeit ist die Verringerung der Komplexität des Beschaffungsvorganges von verteilten und heterogenen Kontextinformationen durch Bereitstellung einer einfach verwendbaren Methode zur Darstellung eines umfassenden, aus verteilten und heterogenen Datenquellen zusammengetragenen Kontextmodells. Im Besonderen werden durch diese Arbeit zwei Probleme addressiert, zum einen daß ein Konsument von umfassenden Kontextinformationen mehrere Datenquellen sowohl kennen und zugreifen können und zum anderen über die zwischen den einzelnen Kontextinformationen in verschiedenen Datenquellen existierenden, zunächst nicht modellierten semantischen Verbindungen Bescheid wissen muß. Das dazu entwickelte Kontextinformationsintegrations- und -darstellungsverfahren kombiniert daher ein die Beschaffung und Integration von Kontextinformationen aus diversen Datenquellen modellierendes Informationsintegrationsmodell mit einem Kontextdarstellungsmodell, welches die abzubildende Realweltdomäne basierend auf ontologischen Informationen durch in problemspezifischer Weise erweiterte Verfahren des Semantic Web in einer möglichst intuitiven, wiederverwendbaren und modularen Weise modelliert. Nach einer fundierten Anforderungsanalyse des entwickelten Prinzips wird dessen Verwendung und Nutzen basierend auf der Skizzierung der wichtigsten allgemeinen Verwendungsmöglichkeiten von Kontextinformationen im betrieblichen Umfeld anhand eines komplexen betrieblichen Anwendungsszenarios demonstriert. Dieses beinhaltet ein Nutzerprofil, das von diversen Anwendungen, u.a. einem kontextsensitiven KFZ-Navigationssystem, einer Restaurantsuchanwendung sowie einem Touristenführer verwendet wird. Probleme hinsichtlich des Datenschutzes, der Integration in existierende Umgebungen und Abläufe sowie der Skalierbarkeit und Leistungsfähigkeit des Verfahrens werden ebenfalls diskutiert. / Context-awareness, which is the systematic consideration of information from the environment of applications, can provide significant benefits in the area of business and technology. To be really useful, i.e. harmonically support real-world processes as human assistants do it, practical applications need a comprehensive and detailed contextual information base that describes all relevant aspects of the real world. As a matter of principle, comprehensive contextual information arises in many places and data sources, e.g. in context-aware infrastructures as well as in "normal" applications, which may have knowledge about the context based on their functionality to support a certain process in the real world. This thesis facilitates the use of contextual information by reducing the complexity of the procurement process of distributed and heterogenous contextual information. Particularly, it addresses the two problems that a consumer of comprehensive contextual information needs to be aware of and able to access several different data sources and must know how to combine the contextual information taken from different and isolated data sources into a meaningful representation of the context. Especially the latter information cannot be modelled using the current state of the art. These problems are addressed by the development of an integration and representation model for contextual information that allows to compose comprehensive context models using information inside distributed and heterogeneous data sources. This model combines an information integration model for distributed and heterogenous information (which consists of an access model for heterogeneous data sources, an integration model and an information relation model) with a representation model for context that formalizes the representation of the respective real world domain, i.e. of the real world objects and their semantic relations in an intuitive, reusable and modular way based on ontologies. The resulting model consists of five layers that represent different aspects of the information integration solution. The achievement of the objectives is rated based on a requirement analysis of the problem domain. The technical feasibility and usefulness of the model is demonstrated by the implementation of an engine to support the approach as well as a complex application scenario consisting of a user profile that integrates information from several data sources and a couple of context-aware applications, e.g. a context-aware navigation system, a restaurant finder application as well as an enhanced tourist guide that use the user profile. Problems regarding security and social effects, the integration of this solution into existing environments and infrastructures as well as technical issues like the scalability and performance of this model are discussed too.
56

網路教學資源應用於國中教師教學歷程之研究—以新竹地區為例 / Investigation of Junior High School Teacher’s Teaching Process Apply Instructional Resource on Internet:Take the Junior High School Teachers in Hsinchu for Example

陳儒瑩, Chen, Ru Ying Unknown Date (has links)
中小學教育改革,走向領域主題的統整,創新教學與評量模式,並注重學習者需求,因此國中教師的教材教法,勢必有所改變,為了提升廣度與深度,教師多尋求網路資源來增加自己教學的多樣化。所以擔任知識傳遞者與課程設計者的國中教師,對於網路資源的選擇與應用,將影響學習成效甚鉅。是故,國中教師的搜尋、選擇、轉化、應用、評估等教學設計歷程,即為本研究探討的主要部分。 本研究透過半結構式深度訪談法,訪談新竹縣市內曾參與資訊教學相關比賽並獲獎的國中教師、或實際應用網路資源於教學中的國中教師、與擔任資訊組長之國中教師,共15位。以瞭解國中教師對於網路教學資源的需求動機、尋求行為與應用經驗。 研究發現:教師認為網路教學資源的特性有助於建構教師之課程認知,營造教學情境,與提升學生思維能力,故樂意將其應用到教學歷程中。依教學任務、任教科目與職責業務之不同而有不同的用途,最常使用的類型依序為:影片、學習單、圖片、測驗題、音訊檔和教案。教師多利用搜尋引擎、影音平台、教育資源網站和資料庫進行查詢。而上級交派、參與研習、自由軟體、同儕分享為教師取得網路教學資源的方式。教師多選用具教育性、完善性、啟發性的資源,偏好以學生需求為主,亦需考量教學目標與個人風格。 網路教學資源需經教師轉換語言、調整難易度、凸顯教育意義、再製外在形式,與創新加值後才可應用,教師多搭配行動學習、專題學習、情境學習、合作學習與互動學習等策略模式,多應用於準備活動與綜合活動之中,且使用時間不會超過整節課的三分之一。教師遭遇問題主要來自授課時間有限,其餘困難皆可透過教學設計予以調整。 最後建議:(一)教育主管機關應鼓勵教師參與資訊與教學設計之研習,多透過線上平台推廣數位教材,宣導各校利用彈性時間開發資訊使用課程。(二)網路資源設計者應設計符應國中學生之生活情境與身心發展狀況,並以學科架構為主,以供教師彈性應用。(三)國中教師應加強資訊知能與課程知識整合之教學設計能力,並參與專業社群,與同儕共同開發適用之教材教法。 關鍵字:網路教學資源;教學設計;資訊整合;教學情境
57

[en] SEMANTIC INTEGRATION OF INFORMATION SYSTEMS / [pt] INTEGRAÇÃO SEMÂNTICA DE SISTEMAS DE INFORMAÇÃO

MARCOS MAGALHAES MOREIRA 21 January 2004 (has links)
[pt] Propõe-se neste trabalho uma abordagem para a integração semântica de informações baseada na linguagem de ontologia OWL, utilizada como linguagem padrão para tornar compatíveis as diversas fontes de informação. Incialmente, apresenta-se o problema de integração de informações e discute-se a aplicação de ontologia para resolvê-lo. Em seguida, indentificam-se as formas de obtenção e extração de ontologias , com ênfase em sistemas de bancos de dados. Da mesma forma, propõem-se alternativas para mapeamento entre classes , propriedades e instâncias das ontologias obtidas. Finalmente, desenvolve-se um estudo de caso para aplicação e validação das idéias apresentadas. Como resultado, propõe-se uma arquitetura de um sistema integrador e discute-se a implementação de alguns dos seus componentes. / [en] This work presents a semantic approach to information integration based on the OWL ontology language, proposed as a standard language to facilitate the integration of different information sources. The information integration problem is first presented and then the use of ontologies to solve it is addressed. Then, strategies to obtain and extract ontologies are identified, emphasizing database system. Alternative mappings between classes , properties and instances of the resulting ontologies are also proposed.Finally, a case study is developed to apply and validate the strategies presented. As a result, an integrator system architecture is proposed and the implementation of some of its components is discussed.
58

Intégration spatio-temporelle de l'information visuelle pour les mouvements oculaires et la perception : =Spatio-temporal integration of visual information for eye movements and perception / Spatio-temporal integration of visual information for eye movements and perception

Simoncini, Claudio 05 December 2013 (has links)
Dans ce travail de thèse, nous avons tout d’abord étudié comment l’information de mouvement est intégrée pour estimer la vitesse d’une texture aléatoire afin de la suivre réflexivement avec les yeux ou d’estimer perception son déplacement. Dans une seconde série d’études, nous avons étudié comment la distribution spatiale du contraste dans une texture affecte à la fois les mouvements oculaires de fixation et la reconnaissance perceptive. A ces fins, nous avons utilisé un nouvel ensemble de stimuli visuels, des textures pseudo-naturelles dans lesquelles on peut finement contrôler la statistique (moyenne, variance) des fréquences spatiales et/ou temporelles. La première partie explore l’intégration et le décodage de information fréquentielle spatio-temporelle visuelle pour les réponses de poursuite réflexes et la discrimination perceptive. Nous montrons que l’action tire complètement partie de la richesse du stimuli en intégrant sur toute la distribution pour estimer la vitesse : accélération initiale, précision et robustesse sont améliorées. Au contraire, la performance perceptive décroit pour des stimuli à bandes passantes larges. Cette dissociation se maintient sur une large place d’intégration temporelle. La seconde partie élargie cette approche à la distribution spatiale de l’information et à ces différentes échelles. Nous montrons que le comportement oculaire de fixation dépend de la composition fréquentielle d’une texture, en termes de moyenne et de fréquence. Saccade et micro-saccades se distribuent au cours de la fixation de façon coordonnée en fonction de cette statistique. In fine, cette dernière joue sur la carte de salience calculée à partir de l’image. / We focused on the impact of the statistical distributions of visual information on these various behavioral responses. We asked first how motion information is integrated to estimate speed in order to perform either a speed discrimination task or to control reflexive tracking eye movements. Next, we investigated how spatial distribution in textures affects both pattern recognition and fixational eye movements. To do so, we used a set of artificial stimuli that are naturalistic textures where we can maintain a tight control on their information contents as for instance their spatio-temporal frequency bandwidth. The first studies compared speed information decoding for ocular following eye movements and perceptual speed discrimination. We found a strong dissociation where ocular following take full advantage by the enlargement of the spatio-temporal frequency bandwidth while perceptual speed discrimination is largely impaired for large bandwidth stimuli. Such dissociation remains over a large temporal integration window. We propose an adaptive gain control mechanism to explain this opposite dependencies. The second series of experimental studies investigate the properties of fixation eye movements (microsaccade and saccade) as a function of the mean and variance of the spatial frequency content of visual static textures. We show that several characteristics of fixational saccades (location, direction and amplitude) varied systematically with the distribution of spatial frequencies. The spatial distribution of the fixation zones could be best predicted from the saliency maps of the stimuli.
59

Mediation on XQuery Views

Peng, Xiaobo 12 1900 (has links)
The major goal of information integration is to provide efficient and easy-to-use access to multiple heterogeneous data sources with a single query. At the same time, one of the current trends is to use standard technologies for implementing solutions to complex software problems. In this dissertation, I used XML and XQuery as the standard technologies and have developed an extended projection algorithm to provide a solution to the information integration problem. In order to demonstrate my solution, I implemented a prototype mediation system called Omphalos based on XML related technologies. The dissertation describes the architecture of the system, its metadata, and the process it uses to answer queries. The system uses XQuery expressions (termed metaqueries) to capture complex mappings between global schemas and data source schemas. The system then applies these metaqueries in order to rewrite a user query on a virtual global database (representing the integrated view of the heterogeneous data sources) to a query (termed an outsourced query) on the real data sources. An extended XML document projection algorithm was developed to increase the efficiency of selecting the relevant subset of data from an individual data source to answer the user query. The system applies the projection algorithm to decompose an outsourced query into atomic queries which are each executed on a single data source. I also developed an algorithm to generate integrating queries, which the system uses to compose the answers from the atomic queries into a single answer to the original user query. I present a proof of both the extended XML document projection algorithm and the query integration algorithm. An analysis of the efficiency of the new extended algorithm is also presented. Finally I describe a collaborative schema-matching tool that was implemented to facilitate maintaining metadata.
60

Evaluating Competition between Verbal and Implicit Systems with Functional Near-Infrared Spectroscopy

Schiebel, Troy A 01 January 2016 (has links)
In category learning, explicit processes function through the prefrontal cortex (PFC) and implicit processes function through the basal ganglia. Research suggested that these two systems compete with each other. The goal of this study was to shed light on this theory. 15 undergraduate subjects took part in an event-related experiment that required them to categorize computer-generated line-stimuli, which varied in length and/or angle depending on condition. Subjects participated in an explicit "rule-based" (RB) condition and an implicit "information-integration" (II) condition while connected to a functional near-infrared spectroscopy (fNIRS) apparatus, which measured the hemodynamic response (HR) in their PFC. Each condition contained 2 blocks. We hypothesized that the competition between explicit and implicit systems (COVIS) would be demonstrated if, by block 2, task-accuracy was approximately equal across conditions with PFC activity being comparatively higher in the II condition. This would indicate that subjects could learn the categorization task in both conditions but were only able to decipher an explicit rule in the RB condition; their PFC would struggle to do so in the II condition, resulting in perpetually high activation. In accordance with predictions, results revealed no difference in accuracy across conditions with significant difference in channel activation. There were channel trends (p < .1) which showed PFC activation decrease in the RB condition and increase in the II condition by block 2. While these results support our predictions, they are largely nonsignificant, which could be attributed to the event-related design. Future research should utilize a larger samples size for improved statistical power.

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