Davant l'augment de l'ús de reconstruccions virtuals als museus arqueològics, aparentment sense una veritable reflexió teòrica (museològica i epistemològica) que les recolzi, aquesta tesi pretén esbrinar la utilitat de la Realitat Virtual com a instrument de presentació de l'Arqueologia i per quins motius, i alhora proposar unes bases teòriques per aquest ús, a partir de la construcció d'un marc teòric i metodològic semiòtic.La tesi s'estructura en tres volums. En el primer es presenta un panorama general del projecte (objectius, metodologia, contribució a l'estat de la qüestió, perspectives de futur) i també les concepcions bàsiques sobre l'Arqueologia (situació epistemològica i funció social), els museus (paper dels objectes, funció social dels museus, funció comunicativa i educativa de l'exposició, primeres paraules sobre l'ús de les TIC als museus) i la Realitat Virtual (a partir de sis vectors d'aproximació a la complexitat del concepte) que han guiat el procés d'investigació. En el segon volum es tracta pròpiament la qüestió de partida i s'intenta esbrinar (a través de la cerca bibliogràfica sobre cada element, la seva aplicació a la RV i la verificació a partir d'avaluacions empíriques publicades) si la Realitat Virtual és útil com a eina de comunicació des de totes les perspectives implicades (percepció, cognició, semiòtica de les imatges/del llenguatge, epistemologia arqueològica, museologia, museografia i aprenentatge), reunides en tres nivells analítics: sintaxi, semàntica i pragmàtica. El tercer volum conté un resum de tota la tesi i les conclusions del procés de recerca, que corresponen als fonaments teòrics sobre l'ús de la RV als museus arqueològics des del punt de vista de la recerca i de la museologia.El present treball no és únic, sinó que ja hi ha hagut altres projectes orientats a la comprensió de la utilitat comunicativa de la RV ja des del moment que les recerques van sortir de i l'àmbit militar i per això es pot situar com a continuador d'aquestes. Però ara aporta algunes novetats, entre les quals cal destacar la construcció d'un marc teòric i metodològic, la Semiòtica, que comporta els següents avantatges: permet aplicar i adaptar la metodologia analítica desenvolupada en altres àmbits; integrar en un discurs coherent les recerques sobre els avantatges i inconvenients de la RV des dels diferents àmbits implicats; obtenir una eina avaluativa per contrastar en el futur aquesta fonamentació teòrica; i, finalment, com a conseqüència pràctica del marc teòric, proporcionar una base racional i explícita per a l'ús científic i divulgatiu de la RV en Arqueologia. / Given the spread of the use of virtual reconstructions in archaeological museums, apparently without a true theoretical consideration (museological and epistemological) to support them, the aim of this thesis is to find out whether and how Virtual Reality is useful for the presentation of Archaeology in museums and at the same time to propose a theoretical bases for this use, through the establishment of a semiotica theoretical and methodological framework.The thesis is structured in three volumes. The first one presents a general overview of the project (goals, methodology, contribution to the state of the art, future perspectives) and also the basic concepts about Archaeology (epistemological situation and social function), museums (role of objects, museums' social function, communicational and educational role of the exhibition, first words about the use of ICT in museums) and Virtual Reality (using six vectors of approximation to the complexity of the concept) that guided the research process. The second volume is devoted to the starting question and tries to find out (through a bibliographical search about each element, its application to VR and its verification through published empirical evaluations) if VR is useful as a communication tool from all the perspectives involved (perception, cognition, semiotics of images/language, archaeological epistemology, museology, museography and learning), distributed in three analytical levels: syntax, semantics and pragmatics. The third volume contains a summary of the thesis and the conclusions of the research project, which correspond to the theoretical foundations of the use of VR in archaeological museums from the research and the museological perspective.The present research project is not unique and can be considered a continuation of early research into the usefulness of VR for learning performed outside the military field. However, it does introduce new elements, amongst which we should highlight the construction of a theoretical and methodological framework, semiotics, which encompasses the following advantages: to apply and adapt the powerful analytical methodology coming from semiotics as well as other fields; to integrate in a coherent discourse research into the advantages and disadvantages of VR from the different fields involved; to obtain an evaluative tool for future verification of these theoretical foundations; and finally, as the practical consequence of the theoretical framework, it provides a rational and explicit basis for the scientific and disseminative use of VR in Archaeology.

Ces dernières années, des recherches ont été menées sur plusieurs techniques reliées à la collection des déchets. Plusieurs découvertes centrales pour le ramassage de miettes par copie ont été réalisées. Cependant, des améliorations sont encore possibles. Dans ce mémoire, nous introduisons des nouvelles techniques et de nouveaux algorithmes pour améliorer le ramassage de miettes. En particulier, nous introduisons une technique utilisant des cadres délimités pour marquer et retracer les pointeurs racines. Cette technique permet un calcul efficace de l'ensemble des racines. Elle réutilise des concepts de deux techniques existantes, card marking et remembered sets, et utilise une configuration bidirectionelle des objets pour améliorer ces concepts en stabilisant le surplus de mémoire utilisée et en réduisant la charge de travail lors du parcours des pointeurs. Nous présentons aussi un algorithme pour marquer récursivement les objets rejoignables sans utiliser de pile (éliminant le gaspillage de mémoire habituel). Nous adaptons cet algorithme pour implémenter un ramasse-miettes copiant en profondeur et améliorer la localité du heap. Nous améliorons l'algorithme de collection des miettes older-first et sa version générationnelle en ajoutant une phase de marquage garantissant la collection de toutes les miettes, incluant les structures cycliques réparties sur plusieurs fenêtres. Finalement, nous introduisons une technique pour gérer les gros objets. Pour tester nos idées, nous avons conçu et implémenté, dans la machine virtuelle libre Java SableVM, un cadre de développement portable et extensible pour la collection des miettes. Dans ce cadre, nous avons implémenté des algorithmes de collection semi-space, older-first et generational. Nos expérimentations montrent que la technique du cadre délimité procure des performances compétitives pour plusieurs benchmarks. Elles montrent aussi que, pour la plupart des benchmarks, notre algorithme de parcours en profondeur améliore la localité et augmente ainsi la performance. Nos mesures de la performance générale montrent que, utilisant nos techniques, un ramasse-miettes peut délivrer une performance compétitive et surpasser celle des ramasses-miettes existants pour plusieurs benchmarks. ______________________________________________________________________________ MOTS-CLÉS DE L’AUTEUR : Ramasse-Miettes, Machine Virtuelle, Java, SableVM.

VEMap (virtual emotion map) can be seen as an advanced application of virtual environment (VE) technology to aid with design activities in architecture and urban planning, which can assist designers to understand users’ opinions. The aim of this research and development work is to create a software application that allows designers to evaluate a user’s emotional response to virtual representations of architectural or urban planning environments. In this project, a galvanic skin response (GSR) test is adopted as an objective measurement for collecting skin conductance data representing emotional arousal. At the same time, the user’s self-reports are used as a form of subjective measurement for identifying emotional valence (i.e. positive, neutral, and negative). Finally, all of the information collected from both GSR readings (objective measurement) and self-reports (subjective measurement) are converted into coloured dots on the base map of the corresponding virtual environment (VE). According to the results of the VEmap evaluation and validation procedure, the beta-testing and evaluation of this project has been confirmed that VEmap may interpret users’ emotional changes as evoked by VE mostly. From a usability perspective, there is no obvious difficulty present for participants on all the controls. Moreover, according to participants’ comments, VEmap may increase users’ interests and promote their involvement if it is applied in architectural design and urban planning. However, gender might have influence on self-report part, and virtual reality usage or 3D game experiences might affect navigation in VE.

Embedding of virtual network (VN) requests on top of a shared physical network poses an intriguing combination of theoretical and practical challenges. Two major problems with the state-of-the-art VN embedding algorithms are their indifference to the underlying substrate topology and their lack of re-optimization mechanisms for already embedded VN requests. We argue that topology-aware embedding together with re-optimization mechanisms can improve the performance of the previous VN embedding algorithms in terms of acceptance ratio and load balancing. The major contributions of this thesis are twofold: (1) we present a mechanism to differentiate among resources based on their importance in the substrate topology, and (2) we propose a set of algorithms for re-optimizing and re-embedding initially-rejected VN requests after fixing their bottleneck requirements. Through extensive simulations, we show that not only our techniques improve the acceptance ratio, but they also provide the added benefit of balancing load better than previous proposals. The metrics we use to validate our techniques are improvement in acceptance ratio, revenue-cost ratio, incurred cost, and distribution of utilization.

Mitrionics is a company based in Lund, Sweden. They develop a platform for FPGA-based acceleration, the platform includes a virtual processor, the Mitrion Virtual Processor, that can be custom built to fit the application that is to be accelerated. The purpose of this thesis is to investigate the possible benefits of using a centralized scheduler for the Mitrion Virtual Processor instead of the current solution which is a distributed scheduler. A centralized scheduler has been implemented and evaluated using a set of benchmark applications. It has been found that the centralized scheduler can decrease the number of registers used to implement the Mitrion Virtual Processor on an FPGA. The size of the decrease depends on the application, and certain applications are more suitable than others. It has also been found that the introduction of a centralized scheduler makes it more difficult for the place and route tool to fit a design on the FPGA resulting in failed timing constraints for the largest benchmark application. / Mitrionics är ett företag i Lund. De utvecklar en platform för FPGA-baserad acceleration av applikationer. Platformen innehåller bland annat en virtuell processor, Mitrion Virtual Processor, vilken kan specialanpassas till applikationen som ska accelereras. Syftet med detta arbete är att implementera en centraliserad schedulerare för Mitrion Virtual Processor och utvärdera vilka möjliga fördelar det kan finnas jämfört med att använda den nuvarande lösningen vilket är en distribuerad skedulerare. En centraliserad skedulerare har implementerats och utvärderas genom att avända en uppsättning testapplikationer. Det har funnits att användandet av en centraliserad skedulerare kan minska antalet register som behövs för att implementera Mitrion Virtual Processor på en FPGA. Vidare har det funnits att storleken på minskningen beror på applikationen och att vissa applikationer lämpar sig bättre än andra. Det har även visat sig att processen att placera logik på FPGAn blir svårare om man använder en centraliserad skedulerare, detta har resulterat i att vissa timing krav inte har mötts när den största testapplikation har syntetiserats.

VEMap (virtual emotion map) can be seen as an advanced application of virtual environment (VE) technology to aid with design activities in architecture and urban planning, which can assist designers to understand users’ opinions. The aim of this research and development work is to create a software application that allows designers to evaluate a user’s emotional response to virtual representations of architectural or urban planning environments. In this project, a galvanic skin response (GSR) test is adopted as an objective measurement for collecting skin conductance data representing emotional arousal. At the same time, the user’s self-reports are used as a form of subjective measurement for identifying emotional valence (i.e. positive, neutral, and negative). Finally, all of the information collected from both GSR readings (objective measurement) and self-reports (subjective measurement) are converted into coloured dots on the base map of the corresponding virtual environment (VE). According to the results of the VEmap evaluation and validation procedure, the beta-testing and evaluation of this project has been confirmed that VEmap may interpret users’ emotional changes as evoked by VE mostly. From a usability perspective, there is no obvious difficulty present for participants on all the controls. Moreover, according to participants’ comments, VEmap may increase users’ interests and promote their involvement if it is applied in architectural design and urban planning. However, gender might have influence on self-report part, and virtual reality usage or 3D game experiences might affect navigation in VE.

Embedding of virtual network (VN) requests on top of a shared physical network poses an intriguing combination of theoretical and practical challenges. Two major problems with the state-of-the-art VN embedding algorithms are their indifference to the underlying substrate topology and their lack of re-optimization mechanisms for already embedded VN requests. We argue that topology-aware embedding together with re-optimization mechanisms can improve the performance of the previous VN embedding algorithms in terms of acceptance ratio and load balancing. The major contributions of this thesis are twofold: (1) we present a mechanism to differentiate among resources based on their importance in the substrate topology, and (2) we propose a set of algorithms for re-optimizing and re-embedding initially-rejected VN requests after fixing their bottleneck requirements. Through extensive simulations, we show that not only our techniques improve the acceptance ratio, but they also provide the added benefit of balancing load better than previous proposals. The metrics we use to validate our techniques are improvement in acceptance ratio, revenue-cost ratio, incurred cost, and distribution of utilization.

With the continuous development of Internet technology, the mode of website operation has become much closer to users. Various types of network operation appear constantly as Web2.0 technology becomes matured, and the shiniest one is Virtual Community. The early development patterns of virtual community were BBS systems, blogs and then the recent social network and micro-blogging(or microblog). Rheingold et al. scholars also believe that virtual communities have become new methods of interaction among people, and this developing pattern is inevitable. Although virtual community is developing rapidly, the relevant domestic literatures and researches on development strategy for virtual community are still very limited. Hence, this research aims to use a systematic way to collect literatures by which we can understand the development background of virtual communities, the operation pattern of virtual community, and how to create the value which between virtual community and Internet users. In addition, this research also chooses a representative case for deep analysis by which we can understand what is the business environment for virtual community in domestic, how to find a niche market to avoid direct contention with competitors when the resources are insufficient, and we can also explore the development strategy for the case and give future recommendations. In conclusion, this study found that virtual community has the following characteristics: website members are not only consumers but also producers, and they can strengthen the interaction features and deepen website users¡¦ preference. Moreover, by combining virtual and physical mode to create win-win situations, focusing on a niche market can create a higher identification among users. Finally, how to overcome the market differences will be the key to expand overseas markets.

The Internet as a new media has two distinct and powerful advantages: interactivity and data collection. The emergence of Web2.0 has taken advantage of these characteristics to provide a powerful platform for sharing opinions and communication in virtual communities. However, successfully managing a virtual community is the same as managing a company. The most important thing is to maintain a good relationship with its customers and retain loyal customers. Much previous research has reported that maintaining a good relationship with customers can produce long-term benefits to the organization. The purpose of this research was to investigate whether customer relationship and loyalty can be affected by the perceived interactivity of a website. We developed a research model and conducted an online survey on eight representative websites to collect data. The results show that there is no direct positive influence between the interactivity of a website and customer loyalty. However, significant indirect relationships exist. That is, the perceived interactivity of a website can affect the relationship quality, which will in turn affects customer loyalty. Relationship quality has a mediating effect between website interactivity and customer loyalty.

The Internet is a common technology nowadays in our daily life. More and more people think it will soon replace traditional mass media and become the new age public forum. However, the cyberspace is not as open, free, and democratic as we may imagine. Actually more and more regulations and rules are imposed on it. But deviating behaviors such as conflicts, crimes, and violence did not decrease with all the regulations and rules. And the hierarchy of power and class did not disappear from the cyberspace as the internet utopians described. The researcher investigated one of the biggest and most popular virtual community in Taiwan, Gassiping Board in PTT Bulletin Board System, in particular regulation and power aspects, and tried to find out what is behind the regulations and how the collective behaviors of the users collide with the power of the administrators and the order of the board. Do they reflect any social value or internet culture? And what is the connection with the real world? With the idea of regulation in Lawrence Lessig¡¦s book Code v2 and the concept of cyberpower, the researcher analysed the important changes and conflicts occurred on Gassiping Board. Gassiping Board can be seen as a free speech market by Lessig¡¦s concept, and the rules serving as laws, which give power to the administrators, along with the internet norms, regulate the behaviour of the users. By the code, the administrators can execute the rules. However, the common users have their own power given by the design of the code to rival the administrators, and they can even change the rules, the norms, and the free speech market of Gassiping Board. Also, some changing effects come from outside the virtual community, namely from the real world. Although the administrators have superior power of technology, most of the time they are low in authority. It is hard for them to regulate all the users under the anti-control culture in the cyberspace. The users of Gassiping Board will gather all their powers when it is necessary, and will even destroy the order and overthrow the power of the administrators. However, this phenomenon indicates self-centredness and lack of respect to others, no matter if it is led by the common users or the administrators. Even though the internet is a modern technology product, in practice modern values such as the quality of democracy, law and order can not work with the internet users in making the virtual community a public sphere with both freedom and order.