Fatigue loading history reconstruction based on the rain-flow technique

Methods are considered for reducing a non-random fatigue loading history to a concise description and then for reconstructing a time history similar to the original. In particular, three methods of reconstruction based on a rain-flow cycle counting matrix are presented. A rain-flow matrix consists of the numbers of cycles at various peak and valley combinations. Two methods are based on a two dimensional rain-flow matrix, and the third on a three dimensional rain-flow matrix. Histories reconstructed by any of these methods produce a rain-flow matrix identical to that of the original history, and as a result the resulting time history is expected to produce a fatigue life similar to that for the original. The procedures described allow lengthy loading histories to be stored in compact form

Retirement Imperiled: The Case Of HELOCs

There is no escape from the onslaught.  Advertisements arrive in the post, in the e-mail inbox, through phone solicitations, internet pop-ups, and radio and television spots. One would think that mortgages (1st mortgages, Reverse Mortgages[1], and Home Equity Lines of Credit, HELOC,[2]) have never been as popular.  The advertisements show consumers using equity from their homes to purchase second homes, do home improvements, take luxury vacations, and go on cruises, purchase new/used/antique cars, boats, motorcycles and other consumer items.  The origin for this trend can be traced to the “Tax Reform of 1986.”  Pre “reform”, mortgages were used to pay for houses only as interest on consumer loans was also a tax deductible item.  Post 1986, the only tax deductible interest for consumers was that paid on a mortgage.  Shortly thereafter, the use of 2nd mortgages to pay for automobiles started and the scope of uses for home equity and instruments designed to tap it has expanded ever since.  As is always the case, choices have consequences and the use of funds obtained through mortgages can have undesirable consequences, particularly on the resources available for retirement.  Thus, this research will explore the changing view of debt on the part of US Consumers’ and the impact of this increased level of debt on consumers’ spending habits, home equity and retirement security

Intellectual Property And Academia

Accompanying the exponential growth in the technology sector in the last decade has been the development and implementation of new policies and protocols regarding intellectual property by many academic institutions.  Characteristically, considerable debate has accompanied the process.  The purpose of this paper is to explore the relationship between technological progress and the development of university policies and protocols pertaining to intellectual property.   Initially, a set of commonly accepted definitions for "Intellectual Property" (IP) is established.  This is accomplished by drawing from federal laws and statutes, the American Association of University Professors guidelines for IP policy content and wording, and several current university policies.  As these definitions are developed, it becomes apparent that one must next broach the issue of where software and other new forms of technology-related materials fit into current classifications.  This paper includes an overview of current approaches to IP agreements among research-level universities in the United States, and a brief coverage of historical precedents.  Special attention is given to recent changes in policies which seem to have been caused by technological advances, and several outside opinions and recommendations for modifications due to technology are presented.  The question of whether or not any changes in IP policy are warranted becomes central, and some care is taken to analyze the consequences of various proposals for modification (or lack thereof), concluding with some recommendations on the topic

Two qubits can be entangled in two distinct temperature regions

We have found that for a wide range of two-qubit Hamiltonians the canonical-ensemble thermal state is entangled in two distinct temperature regions. In most cases the ground state is entangled; however we have also found an example where the ground state is separable and there are still two regions. This demonstrates that the qualitative behavior of entanglement with temperature can be much more complicated than might otherwise have been expected; it is not simply determined by the entanglement of the ground state, even for the simple case of two qubits. Furthermore, we prove a finite bound on the number of possible entangled regions for two qubits, thus showing that arbitrarily many transitions from entanglement to separability are not possible. We also provide an elementary proof that the spectrum of the thermal state at a lower temperature majorizes that at a higher temperature, for any Hamiltonian, and use this result to show that only one entangled region is possible for the special case of Hamiltonians without magnetic fields.Comment: 6 pages, 4 figures, many new result

Quantum Computation as Geometry

Quantum computers hold great promise, but it remains a challenge to find efficient quantum circuits that solve interesting computational problems. We show that finding optimal quantum circuits is essentially equivalent to finding the shortest path between two points in a certain curved geometry. By recasting the problem of finding quantum circuits as a geometric problem, we open up the possibility of using the mathematical techniques of Riemannian geometry to suggest new quantum algorithms, or to prove limitations on the power of quantum computers.Comment: 13 Pages, 1 Figur

A characterization of the Tm graph

AbstractLet n and m be positive integers with n≥2m. The Tm graph with characteristics n, denoted by Gmn, is defined as a graph for which the vertices may be identified with all unordered m-tuples on n symbols so that two vertices are adjacent if and only if the corresponding m-tuples contain a common (m−1)-tuple. The present paper establishes a characterization of Gmn when n>2m(m−1)+4 in terms of conditions similar to, but slightly weaker than, the conditions used by Connor [3] to characterize the triangular (T2) graph and by Bose and Laskar [2] to characterize the tetrahedral (T3) graph