Institution
University of Waterloo
Education•Waterloo, Ontario, Canada•
About: University of Waterloo is a education organization based out in Waterloo, Ontario, Canada. It is known for research contribution in the topics: Population & Context (language use). The organization has 36093 authors who have published 93906 publications receiving 2948139 citations. The organization is also known as: UW & uwaterloo.
Papers published on a yearly basis
Papers
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01 Sep 2004TL;DR: A new rank-join algorithm that makes use of the individual orders of its inputs to produce join results ordered on a user-specified scoring function is introduced and implemented inside a prototype database engine based on PREDATOR.
Abstract: Ranking queries, also known as top-k queries, produce results that are ordered on some computed score. Typically, these queries involve joins, where users are usually interested only in the top-k join results. Top-k queries are dominant in many emerging applications, e.g., multimedia retrieval by content, Web databases, data mining, middlewares, and most information retrieval applications. Current relational query processors do not handle ranking queries efficiently, especially when joins are involved. In this paper, we address supporting top-k join queries in relational query processors. We introduce a new rank-join algorithm that makes use of the individual orders of its inputs to produce join results ordered on a user-specified scoring function. The idea is to rank the join results progressively during the join operation. We introduce two physical query operators based on variants of ripple join that implement the rank-join algorithm. The operators are nonblocking and can be integrated into pipelined execution plans. We also propose an efficient heuristic designed to optimize a top-k join query by choosing the best join order. We address several practical issues and optimization heuristics to integrate the new join operators in practical query processors. We implement the new operators inside a prototype database engine based on PREDATOR. The experimental evaluation of our approach compares recent algorithms for joining ranked inputs and shows superior performance.
397 citations
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TL;DR: In this article, the authors developed models for mass transport inside a porous SOFC anode based on Fick's model (FM), the dusty-gas model (DGM) and the Stefan-Maxwell model (SMM) to predict the concentration overpotential.
397 citations
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TL;DR: It is shown that, for many properties P, one can find a suitable value of k such that if C"k(G) has P, then so does G, and this condition for a graph to be hamiltonian is shown to imply the well-known conditions of Chvatal and Las Vergnas.
397 citations
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TL;DR: In this paper, a case study of an aboriginal community in Taiwan to illustrate the links between tourism and other livelihood strategies is presented, and a sustainable livelihood approach is introduced as being more practical, especially in the common situation in which communities and individuals sustain themselves by multiple activities rather than discrete jobs.
396 citations
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TL;DR: Capillary pressure versus saturation curves for drainage of a wetting phase were measured for several gas diffusion layers that are commonly used in polymer electrolyte membrane fuel cells in this paper, and the results were described by several standard capillary models, the parameters of which can be further used to predict the relative permeability of the phases.
396 citations
Authors
Showing all 36498 results
Name | H-index | Papers | Citations |
---|---|---|---|
John J.V. McMurray | 178 | 1389 | 184502 |
David A. Weitz | 178 | 1038 | 114182 |
David Taylor | 131 | 2469 | 93220 |
Lei Zhang | 130 | 2312 | 86950 |
Will J. Percival | 129 | 473 | 87752 |
Trevor Hastie | 124 | 412 | 202592 |
Stephen Mann | 120 | 669 | 55008 |
Xuan Zhang | 119 | 1530 | 65398 |
Mark A. Tarnopolsky | 115 | 644 | 42501 |
Qiang Yang | 112 | 1117 | 71540 |
Wei Zhang | 112 | 1189 | 93641 |
Hans-Peter Seidel | 112 | 1213 | 51080 |
Theodore S. Rappaport | 112 | 490 | 68853 |
Robert C. Haddon | 112 | 577 | 52712 |
David Zhang | 111 | 1027 | 55118 |