When two distributed parties want to share information stored in ontologies, they have to make sure that they refer to the same concepts. This is done matching the ontologies. This thesis will show the implementation of a method for automatic ontology matching based on the representation of polygons. The method is used to compare two ontologies and determine the degree of similarity between them. The first of the ontologies will be taken as the standard, while the other will be compared to it by analyzing the elements in both. According to the degrees of similarity obtained from the comparison of elements, a set of polygons is represented for the standard ontology and another one for the second ontology. Comparing the polygons we obtain the final result of the similarity between the ontologies. With that result it is possible to determine if two ontologies handle information referred to the same concept.

A dynamic modeling framework was established to predict the position and alignment (turning angle) of a tractor-dolly towing system receiving different driver inputs. This framework consists of three primary components: (1) a state space model to determine position and velocity of the system through Newton’s second law; (2) a model that transfers angular acceleration through each successive towed vehicle; and (3) a polygon model to draw an instantaneous shape of the vehicle representing its location and alignment. Input parameters of this model include initial conditions of the system, real time location of a reference point that can be determined through a beacon and radar system, and instantaneous accelerations, which come from driver maneuvers found on a data collecting system installed on the tractor. The purpose is to create an output that presents the position of the dolly vehicles with reference to the tractor at any time point.

No description available.

No description available.

By studying self-avoiding polygons (SAPs) in (L, M )-tubes (a tubular sublattice of the simple cubic lattice) as a sequence of 2-spans, transfer matrices can be used to obtain theoretical and numerical results for these SAPs. As a result, asymptotic properties of these SAPs, such as pattern densities in a random SAP and the expected span of a random SAP, can be calculated directly from these transfer matrices. These same results can also be obtained for compact polygons, as well as SAPs under the influence of an external force (called compressed or stretched polygons). These results can act as tools for examining the entanglement complexity of SAPs in (L, M )-tubes. In this thesis, it is examined how transfer matrices can be used to develop these tools. The transfer matrix method is reviewed, and previous transfer matrix results for SAPs in (L, M )-tubes, as well as SAPs subjected to an external force, are presented. The transfer matrix method is then similarly applied to compact polygons, where new results regarding compact polygons are obtained, including proofs for a compact concatenation theorem and for a compact pattern theorem. Also in this thesis, transfer matrices are actually generated (via the computer) for relatively small tube sizes. This is done for the general case of SAPs in (L, M )-tubes, as well as for the compact and external force cases. New numerical results are obtained directly from these transfer matrices, and a new algorithm for generating polygons is also developed from these transfer matrices. Compact polygons are actually generated (via the computer) for relatively small tube sizes and spans by using the developed polygon generation algorithm, and new numerical results for pattern densities and limiting free energies are obtained for stretched and compressed polygons.

I mitt examensarbete har jag undersökt om det lämpar sig att använda en manuell metod för att skapa normal maps till icke-organiska polygonmodeller avsedda för datorspel. Jag har använt mig av Photoshop för att måla normal maps som jag sedan applicerar på lågdetaljerade modeller jag skapat, för att höja detaljgraden avsevärt.   Då icke-organisk modellering inbegriper modeller som ska representera hårda ytor, och därmed inte animeras med deformation, så antog jag att denna metod skulle lämpa sig väldigt väl åt dessa ytor som ofta har extremt mjuka former och precisa vassare kanter.   Min metod har varit att studera litteratur om Normal Mapping och hur man använder Photoshop för detta. Jag har sedan utfört praktiskt arbete för att utvärdera hur effektiv metoden är samt vilka fördelar den bidrar med. Jag går igenom teori för normal mapping som jag stödjer med hjälp av faktatexter och instruktions-DVDer i ämnet för att sedan redovisa metoden jag använt i mitt arbete. Jag avslutar sedan med en diskussion kring mitt resultat och redovisar vad jag kommit fram till genom mina experiment.   Jag kommer fram till att Normal Mapping med Photoshop är mycket väl lämpat åt hårda ytor och även bidrar med optimeringar i arbetsflödet både vad gäller organisering, tidsåtgång samt kontroll över resultatet. Ytterligare så ges förslag på förbättringar i pluginets funktionalitet för att öka användarvänligheten.

<p><p>I mitt examensarbete har jag undersökt om det lämpar sig att använda en manuell metod för att skapa normal maps till icke-organiska polygonmodeller avsedda för datorspel. Jag har använt mig av Photoshop för att måla normal maps som jag sedan applicerar på lågdetaljerade modeller jag skapat, för att höja detaljgraden avsevärt.</p><p> </p><p>Då icke-organisk modellering inbegriper modeller som ska representera hårda ytor, och därmed inte animeras med deformation, så antog jag att denna metod skulle lämpa sig väldigt väl åt dessa ytor som ofta har extremt mjuka former och precisa vassare kanter.</p><p> </p><p>Min metod har varit att studera litteratur om Normal Mapping och hur man använder Photoshop för detta. Jag har sedan utfört praktiskt arbete för att utvärdera hur effektiv metoden är samt vilka fördelar den bidrar med. Jag går igenom teori för normal mapping som jag stödjer med hjälp av faktatexter och instruktions-DVDer i ämnet för att sedan redovisa metoden jag använt i mitt arbete. Jag avslutar sedan med en diskussion kring mitt resultat och redovisar vad jag kommit fram till genom mina experiment.</p><p> </p><p>Jag kommer fram till att Normal Mapping med Photoshop är mycket väl lämpat åt hårda ytor och även bidrar med optimeringar i arbetsflödet både vad gäller organisering, tidsåtgång samt kontroll över resultatet. Ytterligare så ges förslag på förbättringar i pluginets funktionalitet för att öka användarvänligheten.</p></p>

Problemas de corte e empacotamento de itens irregulares são problemas que visam determinar um leiaute ótimo de objetos pequenos dentro de objetos maiores, a fim de atender a uma demanda. Estes problemas têm grande importância prática, já que surgem em vários tipos de indústria (como a têxtil, a de móveis e a de calçados). O problema estudado neste trabalho é o problema de corte de itens irregulares em recipientes. Os recipientes são delimitados e o objetivo é encontrar um leiaute dos objetos menores, sem sobreposição, dentro dos objetos maiores utilizando a menor quantidade de recipientes. Propomos um novo método de resolução para o problema. Nosso método é um algoritmo que gerencia um conjunto de heurísticas, de baixo nível, específicas para a resolução do problema com recipientes retangulares e irregulares. Recipientes irregulares são polígonos convexos e não convexos, que podem ser furados. As heurísticas desenvolvidas utilizam uma malha de pontos sobre a técnica de no-fit polygon para evitar a sobreposição dos itens e encontrar posições viáveis no recipiente retangular ou irregular. Os experimentos computacionais foram feitos para um grande conjunto de instâncias, de recipientes retangulares e irregulares. Os resultados demonstram a competitividade do método, que obtêm resultados bons e algumas soluções ótimas, em um tempo computacional aceitável. / Cutting and packing of irregular items are problems that aim to determine the optimum layout of small objects within larger objects (that we call bins), in order to meet a demand. These problems have great practical importance, since they emerge in various types of industry (such as textile, furniture and shoemaking). The problem studied in this work is the irregular bin packing problem. The bins are enclosed and the goal is to find a layout of items, without overlap, within the bins by using the minimum quantity of them. We propose a new method of resolution to this problem. Our method is an algorithm that manages a set of low-level heuristics, specific to solve the problem with rectangular bins and irregular bins. Irregular bins are convex and non-convex polygons, which may contain holes. The developed heuristics uses a mesh of points and the technique of no-fit polygon to avoid the overlapping of items and find feasible positions in rectangular or irregular bins. The computational experiments were performed for a large set of instances, using both rectangular and irregular bins. The results demonstrate the competitiveness of the method, which can get good results and some optimal solutions within an acceptable computational time.

Problemas de corte e empacotamento de itens irregulares são problemas que visam determinar um leiaute ótimo de objetos pequenos dentro de objetos maiores, a fim de atender a uma demanda. Estes problemas têm grande importância prática, já que surgem em vários tipos de indústria (como a têxtil, a de móveis e a de calçados). O problema estudado neste trabalho é o problema de corte de itens irregulares em recipientes. Os recipientes são delimitados e o objetivo é encontrar um leiaute dos objetos menores, sem sobreposição, dentro dos objetos maiores utilizando a menor quantidade de recipientes. Propomos um novo método de resolução para o problema. Nosso método é um algoritmo que gerencia um conjunto de heurísticas, de baixo nível, específicas para a resolução do problema com recipientes retangulares e irregulares. Recipientes irregulares são polígonos convexos e não convexos, que podem ser furados. As heurísticas desenvolvidas utilizam uma malha de pontos sobre a técnica de no-fit polygon para evitar a sobreposição dos itens e encontrar posições viáveis no recipiente retangular ou irregular. Os experimentos computacionais foram feitos para um grande conjunto de instâncias, de recipientes retangulares e irregulares. Os resultados demonstram a competitividade do método, que obtêm resultados bons e algumas soluções ótimas, em um tempo computacional aceitável. / Cutting and packing of irregular items are problems that aim to determine the optimum layout of small objects within larger objects (that we call bins), in order to meet a demand. These problems have great practical importance, since they emerge in various types of industry (such as textile, furniture and shoemaking). The problem studied in this work is the irregular bin packing problem. The bins are enclosed and the goal is to find a layout of items, without overlap, within the bins by using the minimum quantity of them. We propose a new method of resolution to this problem. Our method is an algorithm that manages a set of low-level heuristics, specific to solve the problem with rectangular bins and irregular bins. Irregular bins are convex and non-convex polygons, which may contain holes. The developed heuristics uses a mesh of points and the technique of no-fit polygon to avoid the overlapping of items and find feasible positions in rectangular or irregular bins. The computational experiments were performed for a large set of instances, using both rectangular and irregular bins. The results demonstrate the competitiveness of the method, which can get good results and some optimal solutions within an acceptable computational time.

In this thesis a non-centralized algorithm is proposed to locate nearby servers based on their players’ positions in a massive multiplayer online game server cluster. The purpose of this is to enable that players can visually see each other even though they are connected to different servers. By utilizing peer to peer connection between the servers the algorithm is tolerant against possible hardware failures. The algorithm simplifies the data sent over the network with a new concave polygon creation algorithm which works in linear execution time, enabling fast computations for real-time games. The algorithm works by finding colliding polygons from other servers and the closest polygons based on distance to find nearby servers which information should be shared with. Those two algorithms at this time work in quadratic execution time which is a point of improvement, which could require the concave polygon to be converted into one or several convex polygons. The algorithm is designed to give the user good access on the amount of network traffic sent over the cluster which gives better control and understanding on how much network traffic that will be sent in the cluster. It shows that the algorithm is dependent on how players in the world are distributed over the servers. By having players nearby each other on the same server improves the result of the algorithm. It is shown that compared to having a centralized server, the network traffic on every single node have reduced network traffic than compared to a centralized server. / In den här uppsatsen presenteras en icke-centraliserad algoritm som hittar närliggande servrar baserat på deras spelares positioner i ett massivt multi-spelare online spel med flera servrar. Syftet är att möjliggöra att spelare från olika servrar kan se varandra visuellt även fast de är uppkopplade till olika servrar. Genom att använda sig av ”peer-to-peer” kommunikation i klustret blir algoritmen tolerant mot hårdvarufel. Algoritmen simplifierar data som skickas genom en ny typ av konkav polygon algoritm vilken fungerar i linjär exekveringstid, vilket möjliggör snabba beräkningar för realtidsspel. Algoritmen fungerar genom att hitta kolliderande polygoner från andra servrar och även de mest närliggande baserat på distans för att lokalisera närliggande servrar att dela information med. De här två algoritmerna arbetar i kvadratisk tid vilket skulle kunna förbättras. Detta kan kräva att konkava polygonen konverteras till en eller flera konvexa polygoner. Algoritmen är designad för att ge användaren bra tillgång till hur mycket nätverkstrafik som bör skickas inom klustret vilket ger en bättre kontroll och förståelse över hur mycket data som kommer att skickas totalt. Det visas att algoritmen är beroende av hur spelarna är distribuerade över servrarna. Genom att ha närliggande spelare i världen på samma server förbättras resultatet av algoritmen. Det visas även att jämfört med en centraliserad server så förbättras nätverkstrafiken på varje enskild nod jämfört med trafiken som mottogs av den centraliserade servern.