tailieunhanh - GeoSensor Networks - Chapter 6

Xử lý thông tin trong ứng dụng di động: Một cái nhìn vượt ra ngoài phương pháp tiếp cận cổ điển Các thiết bị di động như điện thoại di động hay trợ lý kỹ thuật số cá nhân cho phép người sử dụng cuối cùng để có được thông tin dựa trên vị trí hiện tại của họ. Thông tin này thường dựa vào khoảng cách (ví dụ như, nhà thuốc gần nhất) và định hướng hướng dẫn. Thông tin phong phú hơn cũng có thể được giao cho người sử dụng điện thoại di động theo hồ sơ. | Information Handling in Mobile Applications A Look beyond Classical Approaches Jochen Schiller Agnès Voisard Freie Universitat Berlin Fraunhofer ISST Berlin schiller@ and Freie Universitat Berlin Germany Germany ABSTRACT Mobile devices such as cellular phones or personal digital assistants now allow end users to obtain information based on their current location. This information is usually based on distance . the nearest drugstore and navigation instructions. Richer information may also be delivered to mobile users according to their profiles for instance their personal preferences and to their history . in relation with the information that they have already received. A new dimension can be introduced if the communication among mobile peers is enabled. Mobile users are then able to exchange information among each other. This paper focuses on two major ways of considering information delivery in this context. The first one is based on a common centralized approach and considers many users taken individually. The second one is a decentralized approach that considers many users who exchange information among each other. We explain the two paradigms and describe the current possibilities for the underlying infrastructure. Keywords location-based services mobile and wireless ad-hoc networks peer-to-peer networking push pull services event notification systems 1. INTRODUCTION Mobile devices such as cellular phones or personal digital assistants now allow end users to obtain information based on their current location such as the nearest drugstore and even the fastest route to it from the current location. However in such location-based services LBS it is desirable to obtain richer and more targeted information than the pure data stored in a database. Typical mobile objects are cars boats or people. A complex mobile application is that of tourists walking around in a city and receiving the right information at