2358820
Subscription Propagation and Content-Based Routing with Delivery Guarantees
Subscription propagation enables efficient content-based routing in publish/subscribe systems and is a challenging problem when it is required to support reliable delivery in networks with redundant routes. We have designed a generic model and a highly-asynchronous algorithm accomplishing these goals. Existing algorithms can be interpreted as different encodings and optimizations of the generic algorithm and hence their correctness can be derived from the generic algorithm.
5871849
Exactly-once delivery in a content-based publish-subscribe system
This paper presents a general knowledge model for propagating information in a content-based publish-subscribe system. The model is used to derive an efficient and scalable Protocol for exactly-once delivery to large numbers (tens of thousands per broker) of content-based subscribers in either publisher order or uniform total order Our protocol allows intermediate content filtering at each hop, but requires persistent storage only at the publishing site. It is tolerant of message drops, message reorderings, node failures, and link failures, and maintains only "soft" state at intermediate nodes. We evaluate the performance of our implementation both under failure-free conditions and with fault injection.
38902380
Construction Algorithm of Principal Curves in the Sense of Limit
Principal curves have been defined as self-consistent, smooth, one-dimensional curves which pass through the middle of a multidimensional data set. They are nonlinear generalization of the first Principal Component. In this paper, we take a new approach by defining principal curves as continuous curves based on the local tangent space in the sense of limit. It is proved that this new principal curves not only satisfy the self-consistent property, but also are the unique existence for any given open covering. Based on the new definition, a new practical algorithm for constructing principal curves is given. And the convergence properties of this algorithm are analyzed. The new construction algorithm of principal curves is illustrated on some simulated data sets.
28734493
AGRID: An Efficient Algorithm for Clustering Large High-Dimensional Datasets
The clustering algorithm GDILC relies on density-based clustering with grid and is designed to discover clusters of arbitrary shapes and eliminate noises. However, it is not scalable to large high-dimensional datasets. In this paper, we improved this algorithm in five important directions. Through these improvements, AGRID is of high scalability and can process large high-dimensional datasets. It can discover clusters of various shapes and eliminate noises effectively. Besides, it is insensitive to the order of input and is a non-parametric algorithm. The high speed and accuracy of the AGRID clustering algorithm was shown in our experiments.
45778067
Children's Use of New Technology for Picture-Taking
Photographs are often associated with children: People have children, they take pictures of them. We don't very often think about children as picture-takers, but our recent work has moved us in that direction. As part of an interest in children's use of new technology, we have studied children's picture-taking with new camera, computer, and Web technology. In this article, we discuss why and how children take pictures. We also discuss the issue of photofakery.
29045473
On Reduct Construction Algorithms
This paper critically analyzes reduct construction methods at two levels. At a high level, one can abstract commonalities from the existing algorithms, and classify them into three basic groups based on the underlying control structures. At a low level, by adopting different heuristics or fitness functions for attribute selection, one is able to derive most of the existing algorithms. The analysis brings new insights into the problem of reduct construction, and provides guidelines for the design of new algorithms
31784785
Tiger: Educational Research in the Age of the Internet