5457719
Macro University
This paper discusses the technical issues related to the Macro University framework. First we present the characteristics of the Macro University, from which the design principles are derived. Then we describe Macro University's software architecture and networking infrastructure. Since the Macro University is a federation of virtual universities, the format and protocol for open information exchange will be very important. Another often neglected issue is the technical tools to facilitate evaluation and assessment. A third issue is a universal interface for distance learning.
892651
A genetic algorithm for optimal 3-connected telecommunication network designs
In this paper, a genetic algorithm for three connected telecommunication network designs is proposed. The genetic algorithm uses a new approach to solution representation, in which constraints such as diameter and connectivity constraints can be easily encoded and two-point crossover with the operation of swapping duplicated nodes ensures solutions generated through genetic evolution are all feasible so that both checking of the constraints and repair mechanism can be avoided. Both efficiency and effectiveness are increased due to no checking of the constraints and no repair mechanism conducted. In fact, our design algorithm for three-connected network design can he extended to a high-connectivity network design.
15963814
A Multiplatform P2P System: its implementation and applications
Peer-to-peer (P2P) computing offers many attractive features, such as collaboration, self-organization, load balancing, availability, fault tolerance and anonymity. However, it also faces many serious challenges. In our previous work, we implemented a synchronous P2P collaboration platform called TOMSCOP. Based on the elementary peer group services offered by the JXTA general framework, TOMSCOP provides the extra four types of services: synchronous message transportation, peer room administration, peer communication support and application space management. By using the four services, different kinds of shared applications for various specific purposes can be relatively easily developed and associated collaborative cyber spaces or communities can be quickly built across the JXTA virtual network overlaid on top of the existing physical networks. However, the TOMSCOP was implemented only in Windows XP OS. In this paper, we extend our previous work and present the implementation of a Multi-Platform P2P System (MPPS). The proposed system operates very smoothly in UNIX Solaris 9 OS, LINUX Suse 9.1 OS, Mac OSX, and Windows XP. In the future study, we would like to evaluate the implemented P2P platform and compare its performance with other P2P systems.
12652571
Implementation of a Pure P2p Collaboration Multiplatform and its Applications
Peer-to-Peer (P2P) computing offers many attractive features, such as collaboration, self-organization, load balancing, availability, fault tolerance and anonymity. However, it also faces many seri...
8267762
GRAM - a P2P system of group revision assistance management
This paper focuses on general design and prototype implementation of a peer-to-peer (P2P) and a proactive mechanism based version management system called GRAM (group revision assistance management). It provides four special features in comparison with other version management systems: higher system reliability and robustness, effective revision collision prevention using proactive agents, context-aware environment for team software revision, a unified XML format for configuration and history files as well as system and agent exchange messages. Every peer holds a shared space synchronized with other peers' ones, and a workspace for a user's ordinary editing. GRAM is implemented using the JXTA technology that consists of the virtual JXTA network and basic peer group services. The system GUI and basic functions in the current prototype are also presented to show its basic usages. By using GRAM, version management of various software development projects can be comfortably conducted.
43686787
A general purpose virtual collaboration room
The general purpose virtual collaboration room (VCR) is an Internet based desktop groupware system that enables a group of remote individuals to flexibly and naturally conduct their collaborative teaching/learning/working without constraints on collaboration types, working styles, group scales, and system platforms. To cope with the complexity, a room metaphor, i.e., emulating a physical room and objects in it, is used as a framework of the system. System implementation becomes no more complex than the case of using one object by identifying associated objects in communication messages between a room server and clients. The VCR provides rich and effective support of awareness of the user, object, space, and their mutual relations. With the use of Java applets for system implementations, users can enter and use a VCR from any standard Java enabled Web browser.
36910358
Design and implementation of a P2P shared Web browser using JXTA
The most shared applications use the client/server model in which, however a server is usually very complex and heavy since all of group managements are done by the server and sometimes becomes a communication bottleneck as all of date exchange among group members are mediated via it. To solve the above problems, our shared browser adopted a pure peer-to-peer (P2P) architecture without using any server A group member or a device called a peer dynamically finds other peers via distributed searching, and directly exchange data with other peers. It supports not only sharing a Web document in a peer group but also synchronously viewing the document and manipulating the browser with further support of some group users' awareness information like a user's moving a cursor, entering a new URL and clicking a hyperlink. It is implemented using JXTA protocols and Java programming language. To make the system applicable over the Internet across firewalls and NATs, the HTTP protocol can be used to transfer data via a pipe, a communication mechanism in JXTA.
22474771
Smart u-Things and Ubiquitous Intelligence
Smart u-things are real things with attached, embedded or blended computers, networks, and/or some other devices such as sensors, actors, e-tags and so on, and they can sense, compute, communicate and take some adaptive actions/reactions/proactions according to their goals, situated contexts, users’ needs, etc. It is envisioned that smart u-thing will be everywhere eventually towards ubiquitous intelligence and smart world. One of the profound implications of such ubiquitous smart u-things is that various kinds and levels of intelligence will exist pervasively in real everyday objects, environments, systems and even ourselves, and possibly be extended from man-made to natural things. The ubicomp/percomp can be regarded, in a sense, as the computing of all these smart/intelligent u-things, which are the basic elements and components of the smart world. After clarifying the essential features and three categories of smart u-things, i.e., smart object, smart space and smart system, the talk is devoted to discuss possible challenges in smart u-things’ research in terms of real world complexity. The main intentions are to examine the possible hard issues to suggest some potential research lines; and to let researchers in this field coolhead and being aware of the hardness of these challenges in making real things truly smart.
1582526
Designing a Context-Aware System to Detect Dangerous Situations in School Routes for Kids Outdoor Safety Care
Ubiquitous computing is targeted at services and applications of computer and communication technologies in the real world. This research, as a part of UbicKids Project, is focused on designing a context-aware system that dynamically detects the possible dangerous situations in the routes where kids go to and return from schools, and provides prompt advices to kids who may encounter some dangerous situations. Based on analyses of typical dangerous situations in school routes, the paper then shows the system architecture and discusses about danger-related context information processing including context description, representation and presentation. Security and privacy issues and possible solutions are also explained. A preliminary system prototype has been implemented and some GUIs are explained. Related work is discussed with comparisons to other research work.
10273602
Asymptotic Convergence Rate of the EM Algorithm for Gaussian Mixtures
It is well known that the convergence rate of the expectation-maximization (EM) algorithm can be faster than those of convention first-order iterative algorithms when the overlap in the given mixture is small. But this argument has not been mathematically proved yet. This article studies this problem asymptotically in the setting of gaussian mixtures under the theoretical framework of Xu and Jordan (1996). It has been proved that the asymptotic convergence rate of the EM algorithm for gaussian mixtures locally around the true solution is o(e0.5()), where > 0 is an arbitrarily small number, o(x) means that it is a higher-order infinitesimal as x 0, and e() is a measure of the average overlap of gaussians in the mixture. In other words, the large sample local convergence rate for the EM algorithm tends to be asymptotically superlinear when e() tends to zero.
34011902
On the correct convergence of the EM algorithm for Gaussian mixtures
It is well-known that the EM algorithm generally converges to a local maximum likelihood estimate. However, there have been many evidences to show that the EM algorithm can converge correctly to the true parameters as long as the overlap of Gaussians in the sample data is small enough. This paper studies this correct convergence problem asymptotically on the EM algorithm for Gaussian mixtures. It has been proved that the EM algorithm becomes a contraction mapping of the parameters within a neighborhood of the consistent solution of the maximum likelihood when the measure of average overlap among Gaussians in the original mixture is small enough and the number of samples is large enough. That is, if the initial parameters are set within the neighborhood, the EM algorithm will always converge to the consistent solution, i.e., the expected result. Moreover, the simulation results further demonstrate that this correct convergence neighborhood becomes larger as the average overlap becomes smaller.