Teorías de la psicometría

Recent hardware advances in embedded mobile devices such as mobile phones have enabled us to envision new applications and services based on the context and the collaboration between the mobile devices and fixed infrastructures available around us. Technologies for peer-to-peer networking include fixed and wireless network technologies, for example, Bluetooth, wireless local area network, WiMax, general packet radio service, and Universal Mobile Telecommunications System, allowing devices both to be mobile

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and to interconnect with mobile or fixed peer-to-peer infrastructures [10]. The capability for ad hoc wireless device-to-device communication between ubiquitous mobile devices such as smartphones and laptop computers opens up the possibility of exciting new types of networking applications. From a practical technological point of view, the capabilities of short-range communication devices over unlicensed links are improving exponentially, in terms of performance measures such as cost, power consumption, throughput, and spectral efficiency. The throughput available on a short-range wireless communication channel operating on an unlicensed band is often far greater than what is available over a long-distance wired communication channel, and is, moreover, free to the user. It is thus a compelling engineering problem to design a self-contained wireless network whose communication resources consist exclusively of short-range unlicensed communication links. This has led to many proposals for wireless ad hoc network designs [11].

2.4.1 Bluetooth Based E-Learning

The Bluetooth based e-learning system proposed by Zhang et al. uses Bluetooth technology as the communication method. The system was developed using the Java API for Bluetooth Wireless Technology on Java platform, making it operating system- independent and device-independent. To be secure, the system uses both authentication and encryption to ensure safety during communications. In order to support the short range of Bluetooth (roughly 10 m), when a client is out of the serving area of the server, it needs to connect to the server via the help of other clients using ad hoc on-demand distance vector routing. In this case, the client will send connect-to-server request to its neighboring clients, which then forward the request to their neighbors. Upon receiving such a request, the server sends back a route reply to the client and the intermediate clients will forward the reply to

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the requesting client. This way, the client will be able to connect to the server. If multiple replies are received via different routes, the route with minimum hop count will be selected for further communication [12]. Using Bluetooth to do similar work in an M-Learning environment would be useful and takes advantage of the mobile hardware technologies. 2.4.2 Proem

Proem is an open computing platform that provides a complete solution for developing and deploying peer-to-peer applications for mobile ad hoc networks. Its objectives included versatility, interoperability, platform independence, built-in security, and high-level development support [13]. Proem is currently no longer developed, but its objectives remain similar to the features our work aims to include.

2.4.3 Mobile Chedar

Mobile Chedar (CHEap Distributed ARchitecture) is an extension to the Chedar peer-to-peer network allowing mobile devices to access the Chedar network and also to communicate with other Mobile Chedar peers. Chedar is a peer-to-peer middleware designed for peer-to-peer applications. Mobile Chedar is implemented using Java 2 Micro Edition (Oracle, Redwood Shores, CA, USA) and uses Bluetooth as a transmission technology for connecting to other peers. Current Bluetooth implementations have the restriction that nodes can be connected to only one piconet at a time. Therefore, the only topology available for constructing Bluetooth network is star-shaped. One device functions as a master and others as slaves (hybrid architecture) [10].

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Peer2Me is an open-source project developing a framework for mobile collaborative applications on mobile phones. Peer2Me enables developers to create collaborative applications for mobile phones using network technologies such as Bluetooth while also using a hybrid peer- to-peer model. The architecture and concepts of Peer2Me are independent of the kind of personal area network (PAN) technology supported in the mobile device. The project was initiated to enable rapid development of proximity-based peer-to-peer applications for mobile devices on the J2ME platform [10].

Mobile Chedar and Peer2Me use the J2ME platform. However, J2ME is being phased out as more and more mobile devices move on to different operating systems, therefore making these systems outdated.

While there have been plenty of e-learning and M-Learning tools and implementations developed, most solutions still fall into a niche situation and are not generic enough to be taken out of the contexts for the applications they were designed for. Instead, we choose to provide an alternative to these systems, one that can take and improve upon the strengths of the previous mentioned methods and combine them into one system, while addressing and hopefully eliminating the weaknesses in those systems previously discussed.

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CHAPTER 3: MODELING, DESIGNING MOBILE LEARNING SYSTEM FOR AD-