Synthetic earthquake hazard

Issued as final reportUniversity of Illinois at Urbana-Champaig

Site response and ground motions

Issued as final repor

Liquefaction susceptibility mapping in Memphis/Shelby County, TN

Issued as final repor

Measurement and Analysis of Civil Engineering Vibrations

Man-made vibrations caused by construction activities, blasting, rail and vehicular traffic, and machinery can have an adverse impact on buildings and facilities, human occupants of buildings, and sensitive equipment housed within these facilities. Comparisons between vibrations are often difficult because of different methods used to measure, analyze, and interpret vibration data. To facilitate these comparisons, standard methods of selecting and mounting transducers, processing vibration data, and interpreting test results are reviewed. Specific measurement and analysis techniques and maximum allowable vibration criteria used for evaluating the influence of vibrations on humans, the potential for cosmetic damage to structures, and the impact on vibration-sensitive equipment are also summarized

The James Webb Space Telescope Mission

Twenty-six years ago a small committee report, building on earlier studies, expounded a compelling and poetic vision for the future of astronomy, calling for an infrared-optimized space telescope with an aperture of at least $4m$. With the support of their governments in the US, Europe, and Canada, 20,000 people realized that vision as the $6.5m$ James Webb Space Telescope. A generation of astronomers will celebrate their accomplishments for the life of the mission, potentially as long as 20 years, and beyond. This report and the scientific discoveries that follow are extended thank-you notes to the 20,000 team members. The telescope is working perfectly, with much better image quality than expected. In this and accompanying papers, we give a brief history, describe the observatory, outline its objectives and current observing program, and discuss the inventions and people who made it possible. We cite detailed reports on the design and the measured performance on orbit.Comment: Accepted by PASP for the special issue on The James Webb Space Telescope Overview, 29 pages, 4 figure

The Science Performance of JWST as Characterized in Commissioning

This paper characterizes the actual science performance of the James Webb Space Telescope (JWST), as determined from the six month commissioning period. We summarize the performance of the spacecraft, telescope, science instruments, and ground system, with an emphasis on differences from pre-launch expectations. Commissioning has made clear that JWST is fully capable of achieving the discoveries for which it was built. Moreover, almost across the board, the science performance of JWST is better than expected; in most cases, JWST will go deeper faster than expected. The telescope and instrument suite have demonstrated the sensitivity, stability, image quality, and spectral range that are necessary to transform our understanding of the cosmos through observations spanning from near-earth asteroids to the most distant galaxies.Comment: 5th version as accepted to PASP; 31 pages, 18 figures; https://iopscience.iop.org/article/10.1088/1538-3873/acb29

Site Characterization in Shelby County, Tennessee Using Advanced Surface Wave Methods

The focus of the current study was to develop improved experimental and analytical methods to increase the applicability and accuracy of seismic surface wave testing for use in geotechnical site characterization. The recent research completed by Zywicki (1999) on the use of array-based techniques for use in active and passive surface wave testing was refined and expanded resulting in the development of the current surface wave testing procedures. The current developments focused on improving the procedures typically used in traditional engineering surface wave studies by implementing array-based testing and analysis procedures and improved signal processing techniques. An experimental testing program was conducted to evaluate the developed procedures and to provide near-surface shear wave velocity (VS) data for the Memphis, Tennessee metropolitan region. This testing program consisted of 11 sites in Mid-America, ten within the Memphis, TN metropolitan area and one site in Northwest Arkansas. The testing program allowed for the comparison with previous data obtained using other in situ techniques, and with traditional surface wave data in order to validate the accuracy of the current methods and to highlight the improved capabilities over traditional surface wave methods. Additionally, active and passive procedures were combined in an effort to improve the range and capabilities of the individual methods allowing for more complete site characterization.National Science Foundation EEC-9701785published or submitted for publicatio

Coring and geophysical logging of a deep well in the Mississippi embayment

Issued as final repor

Attenuation mechanisms and measurements

Issued as final repor