Topography Experiment (TOPEX) Software Document Series Volume 7: TOPEX Mission Radar Altimeter Engineering Assessment Report, February 1994

This document describes the GSFC/WFF analysis of the on-orbit engineering data from the TOPEX radar altimeter, to establish altimeter performance. In accordance with Project guidelines, neither surface truth nor precision orbital data are used for the engineering assessment of the altimeter. The use of such data would imply not only a more intensive and complete performance evaluation, but also a calibration. Such evaluations and.calibrations are outside the scope of this document and will be presented in a separate Verification Report

Obituary

Volume: X

GEOSAT Follow-On (GFO) Altimeter Document Series, Volume 9. GFO and JASON Altimeter Engineering Assessment Report Update: GFO-Acceptance to December 18, 2006, JASON-Acceptance to December 24, 2006. Version 1: June 2007

The initial GFO Altimeter Engineering Assessment Report, March 2001 (NASA/TM-2001-209984/Ver.1/Vol.1) covered the GFO performance from Launch to Acceptance (10 February 1998 to 29 November 2000). The second of the series covered the performance from Acceptance to the end of Cycle 20 (29 November 2000 to 21 November 2001). The third of the series covered the performance from Acceptance to the end of Cycle 42 (29 November 2000 to 30 November 2002). The fourth of the series covered the performance from Acceptance to the end of Cycle 64 (29 November 2000 to 17 December 2003). The fifth of the series covered performance from Acceptance to the end of Cycle 86 (29 November 2000 to 17 December 2004). The sixth of the series covered performance from Acceptance to the end of Cycle 109 (29 November 2000 to 26 December 2005). In this year's GFO report, we have begun the inclusion of analyses of the JASON altimeter. In past years, JASON and TOPEX were compared during our assessment of the TOPEX altimeter; however, with the end of the TOPEX mission, we have developed methods to report on JASON as it relates to GFO. We see no change trend between the three altimeters and conclude all three are stable based on our cross comparison analyses

GEOSAT Follow-On (GFO) Altimeter Document Series, Volume 8: GFO Altimeter Engineering Assessment Report Update:The First 109 Cycles Since Acceptance November 29, 2000 to December 26, 2005

The purpose of this document is to present and document GFO performance analyses and results. This is the fifth Assessment Report since the initial report. This report extends the performance assessment since acceptance to 26 December 2005. The initial GFO Altimeter Engineering Assessment Report, March 2001 (NASA/TM-2001-209984/Ver.1/Vol.1) covered the GFO performance from Launch to Acceptance (10 February 1998 to 29 November 2000). The second of the series covered the performance from Acceptance to the end of Cycle 20 (29 November 2000 to 21 November 2001). The third of the series covered the performance from Acceptance to the end of Cycle 42 (29 November 2000 to 30 November 2002). The fourth of the series covered the performance from Acceptance to the end of Cycle 64 (29 November 2000 to 17 December 2003). The fifth of the series covered performance from Acceptance to the end of Cycle 86 (29 November 2000 to 17 December 2004). Since launch, we have performed a variety of GFO performance studies; an accumulative index of those studies is provided in Appendix A

Project-based pedagogy in interdisciplinary building design adopting BIM

Purpose – This study aims to present a pedagogical practice in the project-based assessment of AEC students’ interdisciplinary building design work adopting BIM. This pedagogical practice emphasizes the impacts of BIM, as the digital collaboration platform, on the cross-disciplinary teamwork design through information sharing. This study also focuses on collecting students’ perceptions of BIM effects in integrated project design. Challenges in BIM adoption from AEC students’ perspective were identified and discussed, and could spark further research needs. Design/Methodology/Approach – Based on a thorough review of previous pedagogical practices of applying BIM in multiple AEC disciplines, this study adopted a case study of the Solar Decathlon residential building design as the group project for AEC students to deliver the design work and construction planning. In total 13 different teams within the University of Nottingham Ningbo China, each group consisting of final year undergraduate students with backgrounds in architecture, civil engineering, and architectural environmental engineering, worked to deliver the detailed design of the solar-powered residential house meeting pre-specified project objectives in terms of architectural aesthetics, structural integrity, energy efficiency, prefabrication construction techniques, and other issues such as budget and scheduling. Each team presented the cross-disciplinary design plan with cost estimate and construction scheduling together with group reports. This pedagogical study collected students’ reflective thinking on how BIM affected their design work, and compared their feedback on BIM to that from AEC industry professionals in previous studies. Findings – The case study of the Solar Decathlon building project showed the capacity of BIM in enabling interdisciplinary collaboration through information exchange and in enhancing communication across different AEC fields. More sustainable design options were considered in the early architectural design stages through the cross-disciplinary cooperation between architecture and building services engineering. BIM motivated AEC student teams to have a more comprehensive design and construction plan by considering multiple criteria including energy efficiency, budget, and construction activities. Students’ reflections indicated both positive effects of BIM (e.g., facilitating information sharing) as well as challenges for further BIM implementation, such as some architecture students’ resistance to BIM, and the lack of existing family types in the BIM library, etc. Research limitations/implications – Some limitations of the current BIM pedagogy were identified through the student group work. For example, students revealed the problem of interoperability between BIM (i.e., Autodesk Revit) and building energy simulation tools. To further integrate the university education and AEC industry practice, future BIM pedagogical work could recruit professionals and project stakeholders in the adopted case studies, for the purpose of providing professional advice on improving the constructability of the BIM-based design from student work. Originality/value – This work provides insights into the information technology applied in the AEC interdisciplinary pedagogy. Students gained the experience of a project-based collaboration and were equipped with BIM capabilities for future employment within the AEC job market. The integrated design approach was embedded throughout the team project process. Overall, this BIM pedagogical practice emphasized the link between academic activities and real-world industrial practice. The pedagogical experience gained in this BIM course could be expanded to future BIM education and research in other themes such as interoperability of building information exchange among different digital tools

GFO and JASON Altimeter Engineering Assessment Report. Update: GFO--Acceptance to December 27, 2007, JASON--Acceptance to December 26, 2007. Version 1: June 2008

The purpose of this document is to present and document GEOSAT Follow-On (GFO) performance analyses and results. This is the eighth Assessment Report since the initial report. This report extends the performance assessment since acceptance to 27 December 2007. Since launch, a variety of GFO performance studies have been performed: Appendix A provides an accumulative index of those studies. We began the inclusion of analyses of the JASON altimeter after the end of the Topographic Experiment (TOPEX) mission. Prior to this, JASON and TOPEX were compared during our assessment of theTOPEX altimeter. With the end of the TOPEX mission, we developed methods to report on JASON as it relates to GFO

GFO and JASON Altimeter Engineering Assessment Report. Update: GFO-Acceptance to End of Mission on October 22, 2008, JASON-Acceptance to September 29, 2008

The purpose of this document is to present and document GEOSAT Follow-On (GFO) performance analyses and results. This is the ninth Assessment Report since the initial report and is our final one. This report extends the performance assessment since acceptance on November 29, 2000 to the end of mission (EOM) on October 22, 2008. Since launch, February 10, 1998 to the EOM, we performed a variety of GFO performance studies; Appendix A provides an accumulative index of those studies. We began the inclusion of analyses of the JASON altimeter after the end of the Topographic Experiment (TOPEX) mission. Prior to this, JASON and TOPEX were compared during our assessment of the TOPEX altimeter. With the end of the TOPEX mission, we developed methods to report on JASON as it related to GFO. It should be noted the GFO altimeter, after operating for over 7 years, was power cycled off to on and on to off approximately 14 times a day for over 18 months in space with no failure. The GFO altimeter proved to be a remarkable instrument providing stable ocean surface measurements for nearly eight years. This report completes our GFO altimeter performance assessment

Social comparisons and organizational support : implications for commitment and retention

Organizational support theory (OST) suggests that employees develop a general perception of the extent to which the organization values their contributions and cares about their well-being (perceived organizational support – POS), and respond to that support through attitudes and behaviors that are beneficial toward the organization. Although OST emphasizes both social exchange and self-enhancement processes, most accounts of POS’s effects are rooted in social exchange. For example, POS’s linkages with commitment and retention have been explained as an exchange of support for positive attitudes and continued employment. This research sheds light on self-enhancement’s less-understood role in fostering these reactions by demonstrating the influence of social comparison effects. Drawing on a sample of 342 employees nested in 82 work-units of a US hospitality company, our analysis demonstrates that favorable POS comparisons with peers in one’s work-unit are positively associated with commitment and retention, whereas unfavorable comparisons are negatively related. Results also show that comparisons taking place in less-supported work-units have stronger impact than comparisons made in those with better support. Our findings extend OST by revealing the importance of social comparisons in engendering responses to organizational support, and in so doing potentially explicate the differential ways social exchange and self-enhancement operate with regard to POS

Controlling pulse propagation in optical fibers through nonlinearity and dispersion management

In case of the nonlinear Schr\"odinger equation with designed group velocity dispersion, variable nonlinearity and gain/loss; we analytically demonstrate the phenomenon of chirp reversal crucial for pulse reproduction. Two different scenarios are exhibited, where the pulses experience identical dispersion profiles, but show entirely different propagation behavior. Exact expressions for dynamical quasi-solitons and soliton bound-states relevant for fiber communication are also exhibited.Comment: 4 pages, 5 eps figure