Length mode piezoelectric ultrasonic transducer for inspection of solid objects

The transducer is constructed from individual transducer elements arranged in an array and configured to exhibit a predominant, longitudinal mode transversely to the array. The elements are interconnected through thin flexible sheets. Each element is individually damped, and the transducer as a whole is electrically damped through resonance with the clamped capacitance and dissipation. Electrical control permits inphase operation of all transducer elements or control with preselected phase differences

High temperature stress-strain analysis

The objectives are threefold: to assist in developing predictive tools needed to improve design analyses and procedures for the efficient and accurate prediction of burner liner structural performance and response; to calibrate, validate, and evaluate these predictive tools by comparing the predicted results with the experimental data; and to evaluate existing as well as advanced temperature and strain measurement instrumentation, through both contact and noncontact efforts, in a simulated turbine engine combustor environment. As the predictive tool, tests, test methods, instrumentation, and data acquisition and reduction methods are developed and evaluated, a proven, integrated analysis/experiment method will be developed that will permit the accurate prediction of the cyclic life of a burner liner

Raising their Children

This personal essay depicts the story of an after school program established in the heart of a low-income neighborhood. It details the struggle the local children face in their failing schools district, and shows how the program, known as Little Wise Child, has been instrumental in making a positive difference in their lives

The effects of a satellite power system on ground-based astronomy

The effects of power transmission from the solar power satellite and of radiation from the ground based rectennas on radio astronomy, radar astronomy, and optical astronomy are discussed. Interference sources, acceptable signal and noise levels, and conflicting site requirements for observatories and rectennas are considered

Validation of structural analysis methods using burner liner cyclic rig test data

The objectives of the hot section technology (HOST) burner liner cyclic rig test program are basically threefold: (1) to assist in developing predictive tools needed to improve design analyses and procedures for the efficient and accurate prediction of burner liner structural response; (2) to calibrate, evaluate and validate these predictive tools by comparing the predicted results with the experimental data generated in the tests; and (3) to evaluate existing as well as advanced temperature and strain measurement instrumentation, both contact and noncontact, in a simulated engine cycle environment. The data generated will include measurements of the thermal environment (metal surface temperatures) as well as structural (strain) and life (fatigue) responses of simulated burner liners and specimens under controlled boundary and operating conditions. These data will be used to calibrate, compare and validate analytical theories, methodologies and design procedures, as well as improvements in them, for predicting liner temperatures, stress-strain responses and cycles to failure. Comparison of predicted results with experimental data will be used to show where the predictive theories, etc. need improvements. In addition, as the predictive tools, as well as the tests, test methods, and data acquisition and reduction techniques, are developed and validated, a proven, integrated analysis/experiment method will be developed to determine the cyclic life of a simulated burner liner

Taking your eyes off the objective: the relationship between income sources and satisfaction with achieving objectives in the UK third sector

As a major funder of the Third Sector, recent cuts in UK Government spending may require Third Sector Organisations (TSOs) to turn to other sources of funding, such as trading activities and public sector contracts. It has been argued that such changes can lead to economic objectives overwhelming social ones. This study utilises data from the 2008 National Survey of Third Sector Organisations (NSTSO) to examine the relationship between the use of these alternative funding sources and organisations’ perceived success in achieving their primary objectives. As predicted by theory, a negative relationship between income from trading activities and achievement of objectives is found. Interestingly public sector contracts do not show a significant link with achievement of objectives. Social enterprise should therefore not be seen as an unqualified panacea for difficulties in social welfare provision in the UK, but public sector contracts need not necessarily lead to a loss of those elements that make the Third Sector provision attractive

A network-based view of regional growth

The need to better understand the mechanisms underlying regional growth patterns is widely recognised. This paper argues that regional growth is partly a function of the value created through inter-organisational flows of knowledge within and across regions. It is proposed that investment in calculative networks by organisations to access knowledge is a form of capital, termed network capital, which should be incorporated into regional growth models. The paper seeks to develop a framework to capture the value of network capital within these models based on the spatial configuration and the nature of the knowledge flowing through networks

Securing the premises

How effective are different home security devices, on their own and in combination with others? Andromachi Tseloni and Rebecca Thompson analyse crime survey data in search of answers