Design of a telescoping tube system for access and handling equipment

Spacecraft processing presents unique problems for the design of ground support equipment. A telescoping tube system consists of a number of nested structural tubes that can be extended and retracted (telescoped) while supporting a load. A typical telescoping tube system provides lateral, torsional, and vertical support for an access platform. Several concepts for improved telescoping tubes were developed with emphasis placed on reliability, ease of maintenance, and cost effectiveness. The most promising prototype design utilizes adjustable rollers running on tracks bolted to the tube sections. A wire rope deployment system ensures that all tube sections are controlled during extension and retraction. Track shimming and roller adjustment allow for fabrication of a high precision tube assembly that does not require extensive machining or unusually large shop equipment. The use of rolling contact eliminates the contamination problems encountered with sliding tubes in previous designs. The prototype design is suitable for indoor or outdoor use. A prototype tube assembly was fabricated and tested for strength, stiffness, maintainability, and endurance

Trees of the Pacific Northwest: A web-based approach to forestry education

Tree identification is a powerful vehicle for introducing people of varying ages and backgrounds to natural resources. For some it\u27s a rewarding and delightful end in itself; for others it provides an important first step into the issues and practices of natural resource management. For most, it\u27s an empowering skill they can share with others. For many, it\u27s a black box process, filled with obscure terms, uncertain choices, and hidden characteristics

A New Sub-Period-Minimum Cataclysmic Variable With Partial Hydrogen Depletion And Evidence Of Spiral Disk Structure

We present time-resolved spectroscopy and photometry of CSS 120422:111127+571239 (=SBS 1108+574), a recently discovered SU UMa-type dwarf nova whose 55 minute orbital period is well below the cataclysmic variable (CV) period minimum of similar to 78 minutes. In contrast with most other known CVs, its spectrum features He I emission of comparable strength to the Balmer lines, implying a hydrogen abundance less than 0.1 of long-period CVs-but still at least 10 times higher than that in AM CVn stars. Together, the short orbital period and remarkable helium-to-hydrogen ratio suggest that mass transfer in CSS 120422 began near the end of the donor star's main-sequence lifetime, meaning that this CV is a strong candidate progenitor of an AM CVn system as described by Podsiadlowski et al. Moreover, a Doppler tomogram of the Ha line reveals two distinct regions of enhanced emission. While one is the result of the stream-disk impact, the other is probably attributable to spiral disk structure generated when material in the outer disk achieves a 2:1 orbital resonance with respect to the donor.NSF AST-1211196, AST-9987045Department of Physics at the University of Notre DameNSF Telescope System Instrumentation Program (TSIP)Ohio Board of RegentsOhio State University Office of ResearchAstronom

Umbilical Design

No abstract availabl

Natural resource education: Getting forest products workers into the flow

The forest products industry employs over 1.4 million people in the U.S.; it ranks among the top ten manufacturing employers in 46 states. Surprisingly, a recent survey of U.S. forest products workers revealed substantial ignorance and misperceptions about forests and forestry issues. Despite this, few educational programs are targeted at this audience. The Oregon Forest Resources Institute has teamed up with Oregon State University\u27s Forestry Media Center to fill this gap with Project FLOW (Forestry Learning Opportunities for Workers). Phase one of this project, completed in summer 1997, analyzed current status of forestry educational opportunities for forest workers in Oregon: existing educational activities, opportunities for new programs, and obstacles to implementing new programs. A mail-in survey, sent to human resource officers or chief executives of 590 forest products businesses in Oregon, indicated that it was important for forest workers to have reliable information about forestry topics. However, fewer than half those responding said that their company currently distributes educational materials or provides on-the-job learning opportunities. Principal obstacles cited were lack of time during the workday, lack of staff, and lack of relevant and effective educational materials. Phase two of this project will use the survey data, as well as information collected from focus groups, site visits, and telephone conversations with key stakeholders, to develop and pilot-test learning materials in various formats. We anticipate that materials developed through this project will have wide application throughout the United States-and that better-informed workers are likely to become better individual decision makers and more effective ambassadors for sound forest management

Using AI/expert system technology to automate planning and replanning for the HST servicing missions

This paper describes a knowledge-based system that has been developed to automate planning and scheduling for the Hubble Space Telescope (HST) Servicing Missions. This new system is the Servicing Mission Planning and Replanning Tool (SM/PART). SM/PART has been delivered to the HST Flight Operations Team (FOT) at Goddard Space Flight Center (GSFC) where it is being used to build integrated time lines and command plans to control the activities of the HST, Shuttle, Crew and ground systems for the next HST Servicing Mission. SM/PART reuses and extends AI/expert system technology from Interactive Experimenter Planning System (IEPS) systems to build or rebuild time lines and command plans more rapidly than was possible for previous missions where they were built manually. This capability provides an important safety factor for the HST, Shuttle and Crew in case unexpected events occur during the mission