• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 114
  • 12
  • 7
  • 7
  • 7
  • 4
  • 4
  • 3
  • 3
  • 2
  • 1
  • 1
  • Tagged with
  • 200
  • 200
  • 49
  • 44
  • 41
  • 41
  • 27
  • 24
  • 23
  • 23
  • 21
  • 21
  • 20
  • 20
  • 19
  • 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.
101

Fuzzy systémy s netradičními antecedenty fuzzy pravidel / Fuzzy systems with non-traditional antecedents of fuzzy rules

Klapil, Ondřej January 2015 (has links)
The aim of this work is to introduce a new type of fuzzy system AnYa. This system, unlike the classical fuzzy systems Takagi-Sugeno and Mamdani, uses a type of antecendent based on real data distribution. As part of the work there will be mentioned system programmed and its functionality will be verified on testing data.
102

Unbounded rule-based expert system for selecting software development methodologies

Macheque, Vhutshilo 16 May 2019 (has links)
MCom (Business Information Systems) / Deparment of Business Information Systems / The extent of success of a given project can be increased by using an appropriate Project Management Methodology (PMM) that takes into account the specific characteristics of the project (such as complexity, size, budget, nature of risk, etc.). PMMs have evolved over the years to become more diverse, complex, with evolving and dynamic ICT platforms. Such PMMs have traditionally been used as frameworks to guide the project management process for decision makers (such as Project Managers, Project Owners and Project Teams). The choice of selecting an appropriate project methodology is daunting; apart from other considerations related to project characteristics such as budget, scope, schedule, performance and resource constraints. One of the vital stages of a successful software development project is selecting a good software development methodology that best suits that project. The aim of this research is to investigate the critical factors to be considered by project managers in the selection of the software development methodology for the project. These critical factors are then used as a foundation for an architecture for an “unbounded rule-based expert system. A survey was conducted amongst project managers to determine the critical factors necessary for the selection of a software development methodology. From the findings of the study, it was established the critical factors revolved around three constructs of Project Excellence Enablers, Excellent Project Management Practices, and Business Value Proposition factors. The findings from this study therefore provided a rationale and a basis for the evolution of an “Unbounded Rule-Based Expert Systems Architecture” as a basis for the selection of the right software development methodology / NRF
103

A Rule-Based Normalization System for Greek Noisy User-Generated Text

Toska, Marsida January 2020 (has links)
The ever-growing usage of social media platforms generates daily vast amounts of textual data which could potentially serve as a great source of information. Therefore, mining user-generated data for commercial, academic, or other purposes has already attracted the interest of the research community. However, the informal writing which often characterizes online user-generated texts poses a challenge for automatic text processing with Natural Language Processing (NLP) tools. To mitigate the effect of noise in these texts, lexical normalization has been proposed as a preprocessing method which in short is the task of converting non-standard word forms into a canonical one. The present work aims to contribute to this field by developing a rule-based normalization system for Greek Tweets. We perform an analysis of the categories of the out-of-vocabulary (OOV) word forms identified in the dataset and define hand-crafted rules which we combine with edit distance (Levenshtein distance approach) to tackle noise in the cases under scope. To evaluate the performance of the system we perform both an intrinsic and an extrinsic evaluation in order to explore the effect of normalization on the part-of-speech-tagging. The results of the intrinsic evaluation suggest that our system has an accuracy of approx. 95% compared to approx. 81% for the baseline. In the extrinsic evaluation, it is observed a boost of approx. 8% in the tagging performance when the text has been preprocessed through lexical normalization.
104

Secure Self-Reconfiguring Services to Mitigate DoS Attacks

Zeller, Silvan January 2019 (has links)
Protecting web services from cyber attacks is a complex problem requiring many layers of defense and mitigation strategies. Out of the diverse range of attacks, denial of service (DoS) attacks on the business logic – or the domain – are poorly studied and no widely accepted general-purpose software product to prevent these attacks exists today. At the same time, in light of the growing importance of e-commerce, defense mechanisms should be designed in a way to be self-reconfiguring, as manual reconfiguration does not scale well. In this work, a rule-based intrusion detection system (IDS) is proposed which logs the behaviour of each user and decides upon a service level based on past behaviour. The implementation is achieved by applying runtime verification (RV), a lightweight formal method which can be utilized to observe traces of user behaviour in real time. The applicability of this approach is measured by means of conducting experiments on a web service, a mock-up hotel chain which grants three different service levels for users based on their individual trust rating. Synthetic traces of bookings and cancellations are issued to account for the detection rate of the IDS and the efficacy of its mitigation strategy. The results indicate that RV is a viable approach for creating a rule-based IDS. The IDS may be tuned to attain a high detection rate of more than 95% while preserving a low false positive rates of less than 3%. Furthermore, attacks are mitigated by changing the business rules for users who have been identified as being malicious, resulting in an increased occupancy of the hotel. Lastly, RV is shown to be significantly more scalable and expressive than regular formal methods, such as model checking. Even though the results seem promising, testing the system on real traces and possibly with varying thresholds remains future work. / Att skydda webbtjänster från cyberattacker är ett komplicerat problem som kräver många lager av försvarsoch lindringsstrategier. Av det olika utbudet av attacker, denial of service attacker (DoS) på affärslogiken – eller domänen – undersöks sällan och ingen allmän accepterad mjukvara för att förhindra dessa attacker finns idag. Samtidigt, mot bakgrund av den växande betydelsen av e-handel, bör förvarsmekanismer utformas för att vara självkonfigurerande, eftersom manuell omkonfigurering inte är skalbart. I detta arbete föreslås ett regelbaserat intrusion detection system (IDS) som loggar varje användares beteende och beslutar om en servicenivå baserad på tidigare beteenden. Implementeringen uppnås genom att använda runtime verification (RV), en lättviktig formell metod som kan användas för att observera spår av användarbeteende i realtid. Tillämpningen av denna metod mäts med hjälp av experiment på en webbtjänst, en mock-up hotellkedja som ger tre olika servicenivåer för användare baserat på deras individuella förtroendevärdering. Syntetiska spår av bokningar och avbokningar används för att redovisa IDS:s detektionsgrad och effektiviteten i dess lindringsstrategi. Resultaten indikerar att RV är ett genomförbart tillvägagångssätt för att skapa ett regelbaserat IDS. Systemet kan vara inställt för att uppnå en hög detektionsgrad på mer än 95% och bevarar samtidigt en låg falsk positiv nivå på mindre än 3%. Dessutom mildras attackerna genom att ändra affärsreglerna för användare som har identifierats som skadliga, vilket resulterar i en ökad beläggning hos hotellet. Slutligen visas RV vara betydligt mer skalbar och uttrycksfull än vanliga formella metoder, till exempel model checking. Även om resultaten verkar lovande, återstår testning av systemet på riktiga spår och eventuellt med olika trösklar som framtida arbete.
105

Autonomous Satellite Operations for CubeSat Satellites

Anderson, Jason Lionel 01 March 2010 (has links) (PDF)
In the world of educational satellites, student teams manually conduct operations daily, sending commands and collecting downlinked data. Educational satellites typically travel in a Low Earth Orbit allowing line of sight communication for approximately thirty minutes each day. This is manageable for student teams as the required manpower is minimal. The international Global Educational Network for Satellite Operations (GENSO), however, promises satellite contact upwards of sixteen hours per day by connecting earth stations all over the world through the Internet. This dramatic increase in satellite communication time is unreasonable for student teams to conduct manual operations and alternatives must be explored. This thesis first introduces a framework for developing different Artificial Intelligences to conduct autonomous satellite operations for CubeSat satellites. Three different implementations are then compared using Cal Poly's CP6 CubeSat and the University of Tokyo's XI-IV CubeSat to determine which method is most effective.
106

Evolutionary Belief Rule based Explainable AI to Predict Air Pollution

Zisad, Sharif Noor January 2023 (has links)
This thesis presents a novel approach to make Artificial Intelligence (AI) more explainable by using a Belief Rule Based Expert System (BRBES). A BRBES is a type of expert system that can handle both qualitative and quantitative information under uncertainty and incompleteness by using if-then rules with belief degrees. The BRBES can model the human inference process and provide transparent and interpretable reasoning for its decisions. However, designing a BRBES requires tuning several parameters, such as the rule weights, the belief degrees, and the inference parameters. To address this challenge, this thesis report proposes to use a Differential Evolution (DE) algorithm to optimize these parameters automatically. A DE algorithm such as BRB adaptive DE (BRBaDE) and Joint Optimization of BRB is a metaheuristic that optimizes a problem by iteratively creating new candidate solutions by combining existing ones according to some simple formulae. The DE algorithm does not require any prior knowledge of the problem or its gradient, and can handle complex optimization problems with multiple objectives and constraints. This model can provide explainability by using different model agnostic method including Local Interpretable Model-agnostic Explanations (LIME) and SHapley Additive exPlanations (SHAP). The proposed approach is applied to calculate Air Quality Index (AQI) using particle data. The results show that the proposed approach can improve the performance and explainability of AI systems compared to other existing methods. Moreover, the proposed model can ensure the balance between accuracy and explainablity in comparison to other models.
107

EXAMINATION OF THE NEURAL CORRELATES UNDERLYING MULTIPLE-EXEMPLAR CATEGORY LEARNING IN BILATERAL RABBIT EYEBLINK CLASSICAL CONDITIONING

Mauldin, Kristin Noel 27 September 2007 (has links)
No description available.
108

Rule-based Methodologies for the Specification and Analysis of Complex Computing Systems

Baggi ., Michele 29 November 2010 (has links)
Desde los orígenes del hardware y el software hasta la época actual, la complejidad de los sistemas de cálculo ha supuesto un problema al cual informáticos, ingenieros y programadores han tenido que enfrentarse. Como resultado de este esfuerzo han surgido y madurado importantes áreas de investigación. En esta disertación abordamos algunas de las líneas de investigación actuales relacionada con el análisis y la verificación de sistemas de computación complejos utilizando métodos formales y lenguajes de dominio específico. En esta tesis nos centramos en los sistemas distribuidos, con un especial interés por los sistemas Web y los sistemas biológicos. La primera parte de la tesis está dedicada a aspectos de seguridad y técnicas relacionadas, concretamente la certificación del software. En primer lugar estudiamos sistemas de control de acceso a recursos y proponemos un lenguaje para especificar políticas de control de acceso que están fuertemente asociadas a bases de conocimiento y que proporcionan una descripción sensible a la semántica de los recursos o elementos a los que se accede. También hemos desarrollado un marco novedoso de trabajo para la Code-Carrying Theory, una metodología para la certificación del software cuyo objetivo es asegurar el envío seguro de código en un entorno distribuido. Nuestro marco de trabajo está basado en un sistema de transformación de teorías de reescritura mediante operaciones de plegado/desplegado. La segunda parte de esta tesis se concentra en el análisis y la verificación de sistemas Web y sistemas biológicos. Proponemos un lenguaje para el filtrado de información que permite la recuperación de informaciones en grandes almacenes de datos. Dicho lenguaje utiliza información semántica obtenida a partir de ontologías remotas para re nar el proceso de filtrado. También estudiamos métodos de validación para comprobar la consistencia de contenidos web con respecto a propiedades sintácticas y semánticas. Otra de nuestras contribuciones es la propuesta de un lenguaje que permite definir y comprobar automáticamente restricciones semánticas y sintácticas en el contenido estático de un sistema Web. Finalmente, también consideramos los sistemas biológicos y nos centramos en un formalismo basado en lógica de reescritura para el modelado y el análisis de aspectos cuantitativos de los procesos biológicos. Para evaluar la efectividad de todas las metodologías propuestas, hemos prestado especial atención al desarrollo de prototipos que se han implementado utilizando lenguajes basados en reglas. / Baggi ., M. (2010). Rule-based Methodologies for the Specification and Analysis of Complex Computing Systems [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/8964
109

Investigation building detection efficiency utilizing machine learning and object-based image analysis techniques

Pulukkutti Arachchige, Madushani Ranjika Chandrasiri January 2024 (has links)
Buildings are not only central to the day-to-day activities but also serve as critical indicators of urban development and transformation. The automatic extraction of building footprints from high-resolution Remote Sensing Imagery (RSI) has emerged as an important and popular tool in urban studies. It helps to enhance the understanding and management of urban sprawl, urban planning, population estimation, resource allocation, and post-disaster damage assessment. In this context, having an automated and robust building detection model is crucial. Deep Learning (DL) model and Object-Based Image Analysis (OBIA) techniques are the main and commonly used for automated building detection. This study investigates the efficacy of a pre-trained DL model and a rule-based model OBIA techniques in building detection across varied resolutions and geographic settings. Employing orthophotos from Luleå, Gävle, and Stockholm, the research assesses the adaptability and robustness of these methods under image properties and urban densities. The DL model was initially trained on 0.25m resolution data of Sweden by Lantmäteriet (Sweden mapping agency). The rule-based model was developed by applying OBIA techniques on behalf of this study. Models were analyzed through six feature agreement statistics including Critical Success Index (CSI), Precision, and Detection Probability (POD). The findings reveal that the DL model consistently outperformed the OBIA approach across all study areas, particularly at the original 25 cm resolution. Gävle showed superior precision with a CSI of 0.8139 for the DL model against a CSI of 0.7493 for OBIA at 25 cm.  The evaluation was improved by considering 50*50 sq. m subsets and building sizes. These evaluations highlight that building size and urban density significantly influence detection accuracy. Larger (> 2500 sq. m) buildings and less dense areas tend to yield higher accuracy across both detection methods. The DL model exhibited high CSI values for very large buildings (>5500 sq. m) in Gävle, surpassing 0.8, while the detection of very small (< 50 sq. m) buildings remained challenging for both methods. Overall, the pre-trained DL model is very sensitive to resolution changes compared to OBIA. Importantly, both give their best performance at the original resolution while DL is superior than OBIA. A rule-based OBIA model is affected by the geographical characteristics more heavily than a DL model. Both models have their best performance in the area with medium building density when medium to very large buildings exist. This study highlights how big the impact of building size, geographic characteristics, and image resolution on the performance of DL and OBIA techniques. However, further investigation is recommended to draw a strong conclusion regarding the impact of resolution on the model performance.
110

Internationell internprissättning : en komparativ studie om hur redovisningstradition påverkar skattemässiga regler / Transfer pricing - a comparative study regarding how accounting tradition affects tax regulation

Johansson, Sara, Sahlman, Viktoria January 2016 (has links)
Syftet med studien är att utreda hur OECDs riktlinjer för internprissättning implementerats i svensk respektive amerikansk lagstiftning, för att fastställa i vilken utsträckning redovisningstradition påverkar implementeringen av skattemässiga regler. För att uppfylla syftet har vi utfört en komparativ studie, som baseras på en kvalitativ innehållsanalys, där vi klassificerar regelverken utifrån i vilken utsträckning de är princip- eller regelbaserade. Undersökningen är relevant då internationell internprissättning av många anses vara den mest prioriterade internationella skattefrågan i dagsläget. Det blir därför relevant att undersöka om redovisningstradition påverkar hur internationella regler för internprissättning implementeras i nationell skattereglering. Enligt vår vetskap har inget liknande klassificeringsförsök gjorts tidigare vilket ytterligare förstärker relevansen av utförd undersökning och analys. Vårt bidrag till forskningen är att försöka beskriva hur verkligheten ser ut avseende om nationell redovisningstradition påverkar implementering av internationella skattemässiga regelverk. Vi vill även bidra till att göra diskussionen kring klassificering av regel- och principbaserade standarder mer nyanserad.För att kunna avgöra om regelverken är princip- eller regelbaserade har vi identifierat olika begrepp och definitioner som indikerar om ett regelverk är regelbaserat eller principbaserat. För att identifiera dessa indikatorer har vi studerat både ekonomisk och juridisk litteratur. Utifrån den information som indikatorerna resulterar i presenterar vi argument för varje undersökt regelverk i de olika länderna, gällande i vilken utsträckning de är princip- eller regelbaserade. Således kan sedan slutsatser dras kring i vilken utsträckning nationella redovisningstraditioner påverkar implementering av internationella skatteregler.I studien diskuteras att hur regler kring internationell internprissättning implementeras i nationell lagstiftning inte bara påverkas av normgivande supranationella organisationer som OECD. Påverkan på det sätt som regler kring internprissättning implementeras kan således ske mellan OECD och medlemsländerna men även mellan medlemsländerna. I studien diskuteras även det faktum att det föreligger en debatt kring om klassificeringen av standarder som regel- eller principbaserade är giltig. Vår studie förstärker bilden av att indelningen är aktuell och har förankring i verkligheten.Vår slutsats är att nationell redovisningstradition, avseende om redovisningen bygger på regler eller principer, påverkar implementering av internationella skatteregler. Det blir tydligt då vår studie visar att OECDs riktlinjer för internprissättning är ett principbaserat regelverk. Vidare har vi fastställt att redovisningen i Sverige bygger på principbaserade regelverk. Påverkan från nationell redovisningstradition kan fastställas då OECDs riktlinjer för internprissättning har implementerats rakt av i Sverige. I USA, där redovisningen bygger på regelbaserade regelverk, har däremot OECDs riktlinjer för internprissättning inte implementerats på något område i nationell lagstiftning. I USA utfärdas istället separata regler kring internprissättning. Vår studie visar att dessa är utformade på ett regelbaserat vis. Sammantaget visar detta att nationell redovisningstradition i hög utsträckning påverkar implementeringen av internationella skatteregler. / The purpose of this dissertation is to examine how OECDs Transfer Pricing Guidelines have been implemented in national regulation in Sweden and in the USA. This to determine to which extent national accounting tradition affects the implementation of international tax regulations. To fulfil the purpose we have undertaken a comparative study, which is based upon a qualitative content analysis, where we classify the regulations based on to which extent they are principle-based or rule-based. The study is relevant since international transfer pricing is considered to be one of the most important tax issues in present time. It is due to this fact relevant to examine if accounting tradition affects the way in which international transfer pricing regulations are implemented in national tax regulations. Due to our knowledge there has not been an attempt to accomplish a classification in this manner previously. This enhances the relevance to the study undertaken. Our contribution to the research field is to try to describe the actuality regarding if national accounting tradition affects implementation of international tax regulations. We also want to make the discussion regarding the classification of principle-based and rule-based standards more nuanced.To be able to determine if the regulations are principle-based or rule-based we have identified concepts and definitions that indicates if regulations are rule-based or principle-based. To identify these indicators we have studied both economic and legal literature. Based on the information that the indicators provide we present arguments regarding to which extent the examined regulations, in the different countries, are principle-based or rule-based. Thus, conclusions regarding to which extent national accounting traditions affects implementation of international tax regulations can be made.In the study we discuss that the way in which regulations regarding transfer pricing is implemented in national legislation is not only affected by normative supranational organisations like the OECD. The impact on the way that regulations regarding transfer pricing are implemented can thus take place between OECD and member countries and also between member countries. In the study we also discuss the fact that there is a debate regarding if the classification of standards as rule-based or principle-based is valid. Our study enhances the impression that the classification is valid and relevant.Our conclusion is that national accounting tradition, regarding if accounting is based on rules or principles, affects the implementations of international tax regulations. This becomes clear since our study shows that OECDs Transfer Pricing Guidelines are principle-based. Furthermore we have determined that accounting in Sweden is based upon principle-based regulations. Since OECDs Transfer Pricing Guidelines have been implemented in Sweden IVwithout adjustments we can determine an impact from national accounting tradition. In the USA, which is a country where accounting is based upon rule-based regulations, the OECD Transfer Pricing Guidelines are not implemented in national regulations. In the U.S. separate regulations regarding transfer pricing are issued. Our study shows that these regulations are formed in a rule-based manner. All together this shows that national accounting tradition largely affect the implementation of international tax regulations.This paper is hereinafter written in Swedish.

Page generated in 0.0304 seconds