53 research outputs found

    Software for Fault-Tolerant Matrix Multiplication

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    Formal Linear Algebra Recovery Environment is a computer program for high-performance, fault-tolerant matrix multiplication. The program is based on an extension of the prior theory and practice of fault-tolerant matrix matrix multiplication of the form C = AB. This extension provides low-overhead methods for detecting errors, not only in C, but also in A and/or B. These methods enable the detection of all errors as long as, in a given case, only one entry in A, B, or C is corrupted. The program also provides for following a low-overhead rollback approach to correct errors once detected. Results of computational experiments have demonstrated that the methods implemented in this program work well in practice while imposing an acceptably low level of overhead, relative to high-performance matrix-multiplication methods that do not afford fault tolerance

    An experimental comparison of cache-oblivious and cache-conscious programs

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    Cache-oblivious algorithms have been advanced as a way of circumventing some of the difficulties of optimizing applica-tions to take advantage of the memory hierarchy of mod-ern microprocessors. These algorithms are based on the divide-and-conquer paradigm – each division step creates sub-problems of smaller size, and when the working set of a sub-problem fits in some level of the memory hierarchy, the computations in that sub-problem can be executed without suffering capacity misses at that level. In this way, divide-and-conquer algorithms adapt automatically to all levels of the memory hierarchy; in fact, for problems like matrix mul-tiplication, matrix transpose, and FFT, these recursive al-gorithms are optimal to within constant factors for some theoretical models of the memory hierarchy. An important question is the following: how well do care-fully tuned cache-oblivious programs perform compared to carefully tuned cache-conscious programs for the same prob-lem? Is there a price for obliviousness, and if so, how much performance do we lose? Somewhat surprisingly, there are few studies in the literature that have addressed this ques-tion. This paper reports the results of such a study in the domain of dense linear algebra. Our main finding is that in this domain, even highly optimized cache-oblivious pro-grams perform significantly worse than corresponding cache-conscious programs. We provide insights into why this is so, and suggest research directions for making cache-oblivious algorithms more competitive

    Limited Liability Companies in Kentucky, Second Edition

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    The Kentucky Limited Liability Company Act, KRS Chapter 275, went into effect July 15, 1994, allowing Kentuckians to conduct business under the LLC form. With over 10,000 LLCs formed in the Commonwealth since the Act\u27s inception, this flexible business entity has become the most popular way to conduct business in Kentucky. The LLC has become so pervasive that business law practitioners, accountants, tax advisors and estate planners must all be well-versed in the myriad of issues and creative applications that accompany this business entity. With flexible tax-treatment and the liability protection of a traditional corporation this entity is utilized not only for business formation and practice but also for business succession and estate planning, the structuring of joint ventures and strategic alliances, as venture capital vehicles, and as tax planning tools. The goal of this monograph is to provide the practitioner with a concise and comprehensive approach to the tools necessary for lawyers to counsel and advise clients on this complex and efficient business entity form. Succinct chapters take the reader through an overview of the LLC entity and the Kentucky LLC Act; choice of entity considerations (both tax and non-tax); the formation, operation and statutory transaction issues which arise for the entity; as well as the new single-member LLC; the professional LLC; the use of the LLC in tax-exempt organizations; wealth transfer planning with LLCs; and securities law, commercial law and benefit issues arising under the LLC entity. Each chapter is set forth in separately numbered paragraphs, present running headers for easy access, and are cross-referenced to other relevant chapters and paragraphs contained in the monograph. Summary and comparative charts, a table of authorities and a statutory appendix are also presented. Finally, a comprehensive index has been created to aid the user in finding relevant subject treatments
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