Operational cost drivers

To be economically viable, the operations cost of launch vehicles must be reduced by an order of magnitude as compared to the Space Transportation System (STS). A summary of propulsion-related operations cost drivers derived from a two-year study of Shuttle ground operations is presented. Examples are given of the inordinate time and cost of launch operations caused by propulsion systems designs that did not adequately consider impacts on prelaunching processing. Typical of these cost drivers are those caused by central hydraulic systems, storable propellants, gimballed engines, multiple propellants, He and N2 systems and purges, hard starts, high maintenance turbopumps, accessibility problems, and most significantly, the use of multiple, nonintegrated RCS, OMS, and main propulsion systems. Recovery and refurbishment of SRBs have resulted in expensive crash and salvage operations. Vehicle system designers are encouraged to be acutely aware of these cost drivers and to incorporate solutions (beginning with the design concepts) to avoid business as usual and costs as usual

CIRCA 2000 operations criteria

The current Shuttle Program was used as a working model and certified data source in the identification of Space Transportation System (STS) operational cost drivers. Changes to flight hardware, processing methodologies, and identification of automation applications that would reduce costs were derived by reference to that data. The CIRCA 2000 Criteria were developed using these critical analyses of the on-going Shuttle Program. Several innovative suggestions are reviewed

Cognitive Dissonance, Pessimism, and Behavioral Spillover Effects

This paper reports results from a unique two-stage experiment designed to examine the spillover effects of optimism and pessimism. In stage 1, we induce optimism or pessimism onto subjects by randomly assigning a high or low piece rate for performing a cognitive task. We find that participants receiving the low piece rate are significantly more pessimistic with respect to performance on this task. In stage 2 individuals participate in an ultimatum game. We find that minimum acceptable offers are significantly lower for pessimistic subjects, though this pessimism was generated in a completely unrelated environment. These results highlight the existence of important spillover effects that can be behaviorally and economically important - for example, pessimism regarding one’s initial conditions (e.g., living in poverty) may have spillover effects on one’s future labor market outcomes.

Evaluation of ozone difluoride as a liquid propellant additive Final report

Ozone difluoride evaluated as liquid propellant additiv

Paper Session IV-B - Design the Support rather than Support the Design

A major portion (73%) of the life cycle cost of the Space Shuttle is related to operations; this paper presents recommendations for reducing that cost. Operational cost drivers at the launch site are identified, based on an examination of Shuttle operational data collected over the past two and one half years. For decades, the launch vehicles of the Free World have been designed for performance, with very little attention given to consideration for support and/or maintainability. Examples are: multiple commodities; toxic materials; complexity; ordnance; inaccessibility; unique systems or components (lack of commonality and multiple function); Flight hardware designs drive Launch Site resources for: test operations to demonstrate hardware/software conformance to design parameters; test personnel—numbers and skill mix; ground support equipment; facilities; assembly; and maintenance. A case is made for incorporating support and maintainability criteria in the design process

Using Implicit Instructional Cues to Influence False Memory Induction

Previous research has shown that explicit cues specific to the encoding process (endogenous) or characteristic of the stimuli themselves (exogenous) can be used to direct a reader’s attentional resources towards either relational or item-specific information. By directing attention to relational information (and therefore away from item-specific information) the rate of false memory induction can be increased. The purpose of the current study was to investigate if a similar effect would be found by manipulating implicitly endogenous cues. An instructional manipulation was used to influence the perceptual action participants performed on word stimuli during the encoding of DRM list words. Results demonstrated that the instructional conditions that encouraged faster processing also led to an increased rate of false memory induction for semantically related words, supporting the hypothesis that attention was directed towards relational information. This finding supports the impoverished relational processing account of false memory induction. This supports the idea that implicitly endogenous cues, exogenous cues (like font) or explicitly endogenous cues (like training) can direct attentional resources during encoding

CBI limits on 31 GHz excess emission in southern HII regions

We have mapped four regions of the southern Galactic plane at 31 GHz with the Cosmic Background Imager. From the maps, we have extracted the flux densities for six of the brightest \hii regions in the southern sky and compared them with multi-frequency data from the literature. The fitted spectral index for each source was found to be close to the theoretical value expected for optically thin free-free emission, thus confirming that the majority of flux at 31 GHz is due to free-free emission from ionised gas with an electron temperature of $\approx 7000-8000$ K. We also found that, for all six sources, the 31 GHz flux density was slightly higher than the predicted value from data in the literature. This excess emission could be due to spinning dust or another emission mechanism. Comparisons with $100 \mu$m data indicate an average dust emissivity of $3.3\pm1.7 \mu$K (MJy/sr)$^{-1}$, or a 95 per cent confidence limit of $<6.1 \mu$K (MJy/sr)$^{-1}$. This is lower than that found in diffuse clouds at high Galactic latitudes by a factor of $\sim 3-4$. The most significant detection ($3.3\sigma$) was found in $G284.3-0.3$ (RCW49) and may account for up to $\approx 30$ per cent of the total flux density observed at 31 GHz. Here, the dust emissivity of the excess emission is $13.6\pm4.2 \mu$K (MJy/sr)$^{-1}$ and is within the range observed at high Galactic latitudes. Low level polarised emission was observed in all six sources with polarisation fractions in the range $0.3-0.6$ per cent. This is likely to be mainly due to instrumental leakage and is therefore upper an upper limit to the free-free polarisation. It corresponds to an upper limit of $\sim1$ per cent for the polarisation of anomalous emission.Comment: Accepted in MNRAS. 12 pages, 10 figures, 5 table

A Pilot Study of Transplanting Methods for Wilding American Beech (Fagus grandifolia)

American beech is facing pressure from a number of emergent health issues including beech bark disease, beech leaf disease, beech leaf mining weevil, and climate and habitat change. Interest has increased in the propagation of American beech in response to the demand for more disease-resistant American beech for use in restoration. This study describes the first steps towards publishing methods for transplanting beech in order to supplement commercially available beech seedlings in an area with multiple agencies depleting the existing stock of slow growing species. American beech seedlings were purchased from a nursery in northern Michigan and were excavated from natural stands in the Hiawatha National Forest. Survival rates for these cohorts were compared after a growing season and by the relative amounts of fine roots present on the trees. Generally, the wildling seedlings had a higher survivability than the purchased bare root seedlings. Future work is proposed that could clarify the conditions leading to the higher survival in these wildling seedlings, including the potential for handling the time or age of the seedlings to influence survival