Energy in elastic fiber embedded in elastic matrix containing incident SH wave

A single elastic fiber embedded in an infinite elastic matrix is considered. An incident plane SH wave is assumed in the infinite matrix, and an expression is derived for the total energy in the fiber due to the incident SH wave. A nondimensional form of the fiber energy is plotted as a function of the nondimensional wavenumber of the SH wave. It is shown that the fiber energy attains maximum values at specific values of the wavenumber of the incident wave. The results obtained here are interpreted in the context of phenomena observed in acousto-ultrasonic experiments on fiber reinforced composite materials

Managing Credit Union Capital: A Strategic Planning Tool for the New Millennium

This study provides a statistical tool for assisting credit union managers in planning capital/asset ratio strategies for optimum operating efficiency. Focus groups, personal interviews, and survey data from more than 165 randomly selected responses form the basis of our model. The survey solicited information concerning the relationship between nine independent variables and expected optimum gross and net capital/asset ratios. The most statistically significant variables were total loan/assets, real estate loans/total loans, unsecured and credit card loans, the operating expense ratio, and the delinquency ratio. Two multiple regression equations were derived from these data. They allow operating managers to enter their specific credit union data into the equations and generate target goals for optimizing their gross and net capital/asset ratios over the next two years

Modified Penning-Malmberg Trap for Storing Antiprotons

A modified Penning-Malmberg trap that could store a small cloud of antiprotons for a relatively long time (weeks) has been developed. This trap is intended for use in research on the feasibility of contemplated future matter/antimatter-annihilation systems as propulsion sources for spacecraft on long missions. This trap is also of interest in its own right as a means of storing and manipulating antiprotons for terrestrial scientific experimentation. The use of Penning-Malmberg traps to store antiprotons is not new. What is new here is the modified trap design, which utilizes state-of-the-art radiofrequency (RF) techniques, including ones that, heretofore, have been used in radio-communication applications but not in iontrap applications. A basic Penning-Malmberg trap includes an evacuated round tube that contains or is surrounded by three or more collinear tube electrodes. A steady axial magnetic field that reaches a maximum at the geometric center of the tube is applied by an external source, and DC bias voltages that give rise to an electrostatic potential that reaches a minimum at the center are applied to the electrodes. The combination of electric and magnetic fields confines the charged particles (ions or electrons) for which it was designed to a prolate spheroidal central region. However, geometric misalignments and the diffusive cooling process prevent the steady fields of a basic Penning- Malmberg trap from confining the particles indefinitely. In the modified Penning-Malmberg trap, the loss of antiprotons is reduced or eliminated by use of a "rotating-wall" RF stabilization scheme that also heats the antiproton cloud to minimize loss by matter/antimatter annihilation. The scheme involves the superposition of a quadrupole electric field that rotates about the cylindrical axis at a suitably chosen radio frequency. The modified Penning-Malmberg trap (see Figure 1) includes several collinear sets of electrodes inside a tubular vacuum chamber. Each set comprises either a single metal tube or else a tube that is segmented into four electrodes that subtend equal angles about the cylindrical axis. The output of an RF signal generator is fed through a 90 hybrid coupler and then through two baluns to generate four replicas of the signal at relative phase shifts of 0 , 90 , 180 , and 270 (see Figure 2). These signal replicas are fed through 6-dB directional couplers, then via coaxial cables to the vacuum chamber. The signal is then routed to a phase cancellation network, which filters out the drive signal with the difference representing the plasma interaction. Inside the vacuum chamber, twisted-pair wires feed the signals from the coaxial cables to the four electrodes of each segmented electrode tube

Winifred S. Raymond Correspondence

Entries include brief biographical information and a typed biography of the librarian of the Bangor Public Library, a typed letter of presentation and a biographical letter on Bangor Public Library stationery, as well as correspondence with the Maine State Library concerning the new Federal tax law and donations of books from authors

The Credit Union Industry in the Financial Services Marketplace of the 21st Century

The credit union industry has been consolidating for more than a quarter century, as well as broadening and diversifying its product and service offerings. In this period the operating performance and internal structure of the industry has been evolving in a number of ways. This study examines the changing chartering patterns of credit unions between state and federal. The number of credit unions, the number of members, and the assets held by credit unions in each of these categories have been growing at different rates. We examine these patterns of development and project the expected changes in structure through the year 2010

Optimum Capital/Asset Ratios in the Credit Union Industry: A Managerial Perspective

This study provides a statistical tool for assisting credit union managers in planning capital/asset ratio strategies for optimum operating efficiency. Focus groups, personal interviews, and survey data from randomly selected responses form the basis of our model. Two multiple regression equations allow operating managers to set target goals for their gross and net capital/asset ratios

Credit Union Industry Consolidation in the 1990s

The financial services industry has been consolidating for more than two decades. This study examines the extent and affects of the deregulation movement on the credit union industry. It identifies a number of operational factors that have contributed to growth of the average size credit union in the 1990s and benefits to members that have resulted from this consolidation trend