TEMPUS: A proposal for international time transfer and precision tracking satellite

Very Long Baseline Interferometry (pulsars), Television relay via satellite, portable clocks, Navigation Technology Satellite, and Loran C are described and compared

The Legacy of the Tevatron in the Area of Accelerator Science

For more than 25 years the Tevatron was the highest energy accelerator in the world, providing the first access to particle collisions beyond 1 TeV and achieving an ultimate performance a factor of four hundred beyond the original design goals. This article reviews the many formidable challenges that were overcome, and the knowledge gained, in building, operating, and improving the Tevatron over its lifetime. These challenges included: the first operations of an accelerator based on superconducting magnets, production of antiprotons in sufficient numbers to support a useable luminosity, management of beam-beam, intrabeam, and other collective effects, novel manipulations of the beam longitudinal phase space, and development and application of a wide variety of innovative technologies. These achievements established the legacy of the Tevatron as the progenitor of all subsequently constructed high energy hadron colliders.Comment: Submitted to Annual Reviews of Nuclear and Particle Scienc

Advancing image quantification methods and tools for analysis of nanoparticle electrokinetics

Image processing methods and techniques for high-throughput quantification of dielectrophoretic (DEP) collections onto planar castellated electrode arrays are developed and evaluated. Fluorescence-based dielectrophoretic spectroscopy is an important tool for laboratory investigations of AC electrokinetic properties of nanoparticles. This paper details new, first principle, theoretical and experimental developments of geometric feature recognition techniques that enable quantification of positive dielectrophoretic (pDEP) nanoparticle collections onto castellated arrays. As an alternative to the geometric-based method, novel statistical methods that do not require any information about array features, are also developed using the quantile and standard deviation functions. Data from pDEP collection and release experiments using 200 nm diameter latex nanospheres demonstrates that pDEP quantification using the statistic-based methods yields quantitatively similar results to the geometric-based method. The development of geometric- and statistic-based quantification methods enables high-throughput, supervisor-free image processing tools critical for dielectrophoretic spectroscopy and automated DEP technology development

The Sulzer Hip Replacement Recall Crisis: A Patient\u27s Perspective

This case discusses a product recall that resulted from a manufacturing defect and the degree to which the company distributed accurate and timely information to affected patients. More specifically, the case examines the crisis communication of Sulzer Orthopedics and its efforts to negotiate the interests of various stakeholders, while limiting liability. Written from the perspective of a patient, the case raises interesting questions regarding organizational duties related to product liability. It also provides valuable insights into how organizational communication may have both short- and long-term effects on its relationship with patients and physicians, among others

Toolboxes and handing students a hammer: The effects of cueing and instruction on getting students to think critically

Developing critical thinking skills is a common goal of an undergraduate physics curriculum. How do students make sense of evidence and what do they do with it? In this study, we evaluated students' critical thinking behaviors through their written notebooks in an introductory physics laboratory course. We compared student behaviors in the Structured Quantitative Inquiry Labs (SQILabs) curriculum to a control group and evaluated the fragility of these behaviors through procedural cueing. We found that the SQILabs were generally effective at improving the quality of students' reasoning about data and making decisions from data. These improvements in reasoning and sensemaking were thwarted, however, by a procedural cue. We describe these changes in behavior through the lens of epistemological frames and task orientation, invoked by the instructional moves

Selection of a seventh spectral band for the LANDSAT-D thematic mapper

The author has identified the following significant results. Each of the candidate bands were examined in terms of the feasibility of gathering high quality imagery from space while taking into account solar illumination, atmospheric attenuation, and the signal/noise ratio achievable within the TM sensor constraints. For the 2.2 micron region and the thermal IR region, inband signal values were calculated from representative spectral reflectance/emittance curves and a linear discriminant analysis was employed to predict classification accuracies. Based upon the substantial improvement (from 78 t0 92%) in discriminating zones of hydrothermally altered rocks from unaltered zones, over a broad range of observation conditions, a 2.08-2.35 micron spectral band having a ground resolution of 30 meters was recommended

Bosch CO2 Reduction System Development

Development of a Bosch process CO2 reduction unit was continued, and, by means of hardware modifications, the performance was substantially improved. Benefits of the hardware upgrading were demonstrated by extensive unit operation and data acquisition in the laboratory. This work was accomplished on a cold seal configuration of the Bosch unit