Knowledge has always been a decisive factor of humankind's social evolutions. Collecting the world's knowledge is one of the greatest challenges of our civilization. Knowledge involves the use of information but information is not knowledge. It is a way of acquiring and understanding information. Improving the visibility and the accessibility of information requires to organize it efficiently. This thesis focuses on this general purpose.<p><p>A fundamental objective of computer science is to store and retrieve information efficiently. This is known as the dictionary problem. A dictionary asks for a data structure which allows essentially the search operation. In general, information that is important and popular at a given time has to be accessed faster than less relevant information. This can be achieved by dynamically managing the data structure periodically such that relevant information is located closer from the search starting point. The second part of this thesis is devoted to the development and the understanding of self-adjusting dictionaries in various models of computation. In particular, we focus our attention on dictionaries which do not have any knowledge of the future accesses. Those dictionaries have to auto-adapt themselves to be competitive with dictionaries specifically tuned for a given access sequence. <p><p>This approach, which transforms the information structure, is not always feasible. Reasons can be that the structure is based on the semantic of the information such as categorization. In this context, the search procedure is linked to the structure itself and modifying the structure will affect how a search is performed. A solution developed to improve search in static structure is the hotlink assignment. It is a way to enhance a structure without altering its original design. This approach speeds up the search by creating shortcuts in the structure. The first part of this thesis is devoted to this approach. / Doctorat en Sciences / info:eu-repo/semantics/nonPublished

“And what we can see and imagine gives us faith for what surpasses the imagination” (Wells, 1902) A rich cultural heritage can serve as a vehicle that enlivens all levels of educational development and promotes an interdisciplinary dialogue concerning preservation goals and objectives. A comprehensive, integrated information base is essential to sustaining the viability of this diverse cultural heritage and to promoting a national preservation agenda. The collective experiences and practices of local preservation efforts, when assembled into a readily accessible knowledge base, can effectively inform efforts to resolve preservation challenges nationwide. As the ideal of historic preservation has come to accommodate a variety of philosophical perspectives, so too must the efforts to adapt new technologies to the tasks of cultural resource management. The development of more effective mechanisms for informing the decision processes will encourage resource administrators to assume greater responsibility for the management of cultural resources. It will enable the preservation community to strengthen its social, economic, and political advocacy for the conservation and celebration of our delicate, yet durable, cultural roots. Through the outreach to public and private constituencies, and through the development of market applications for cost effective preservation products, technologies, and services, the positive socioeconomic benefits of sensible, sensitive cultural resource management will serve to institutionalize the perception of our cultural heritage as an integral part of a healthy, informed society. The goal of this work is to demonstrate through developed prototypes and projected scenarios, alternatives for technology transfer, adaptation, and application that can facilitate better informed decisions about the management of an increasingly threatened cultural heritage. This body of information will contribute to the resolution of the most critical needs of the preservation process, and will enhance the ability of private, state, and federal agencies to meet their legal obligations in the management and protection of our cultural heritage. The work demonstrates that the whole of the preservation process can be enhanced by exploiting the opportunities inherent in emerging information management technologies. / Ph. D.