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51.
FA Chervenak RM Greenlee L Lewenstein HM Tovell 《Canadian Metallurgical Quarterly》1981,57(3):379-381
Massive ascites associated with pelvic endometriosis is an unusual occurrence. Two cases recently encountered by the authors are presented, and 7 additional cases from the literature are reviewed. Clinical courses and operative findings are described, and the management of the cases is presented. The etiology of ascites is explored and the possibility of conservative surgery and hormonal control with danazol is discussed. 相似文献
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A matching in a graph is a set of edges no two of which share a common vertex. In this paper we introduce a new, specialized
type of matching which we call uniquely restricted matchings, originally motivated by the problem of determining a lower bound
on the rank of a matrix having a specified zero/ non-zero pattern.
A uniquely restricted matching is defined to be a matching M whose saturated vertices induce a subgraph which has only one perfect matching, namely M itself. We introduce the two problems of recognizing a uniquely restricted matching and of finding a maximum uniquely restricted
matching in a given graph, and present algorithms and complexity results for certain special classes of graphs.
We demonstrate that testing whether a given matching M is uniquely restricted can be done in O(|M||E|) time for an arbitrary graph G=(V,E) and in linear time for cacti, interval graphs, bipartite graphs, split graphs and threshold graphs. The maximum uniquely
restricted matching problem is shown to be NP-complete for bipartite graphs, split graphs, and hence for chordal graphs and
comparability graphs, but can be solved in linear time for threshold graphs, proper interval graphs, cacti and block graphs.
Received April 12, 1998; revised June 21, 1999. 相似文献
53.
Brandt Joel Guo Philip J. Lewenstein Joel Dontcheva Mira Klemmer Scott R. 《Software, IEEE》2009,26(5):18-24
Programmers often write code to prototype, ideate, and discover. To do this, they work opportunistically, emphasizing speed and ease of development over code robustness and maintainability. How do opportunistic programmers make these trade-offs, and how does their work's structure compare to more formal software engineering practices? Opportunistic programmers build software using high-level tools and often add new functionality via copy-and-paste from the Web. They iterate rapidly, consider code impermanent, and find debugging particularly challenging. Five opportunistic-programming principles can help guide the development of tools that explicitly support prototyping in code. 相似文献
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