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Solid Modeling and Stereolithography as a Solid Freeform Fabrication Technique at Texas Instruments Incorporated
Over the past 25 years, the CAE/CAD/CAM industry has developed technological advances that
have provided industrial users the ability to increase productivity and decrease the cycle time necessary
for product development. These technologies include basic wireframe and surface design, specializedapplication
software packages, finite element analysis, numerical control, solid modeling, and rapid
prototyping.
Each of these technologies plays a significant role in industry today. The Defense Systems & Electronics
Group of Texas Instruments currently uses these technologies in the mechanical design engineering
process. This paper discusses the two specific technologies of solid modeling and rapid prototyping
(specifically stereolithography), including their advantages, benefits, and practical applications within the
Texas Instruments Defense Systems & Electronics Group. This paper also discusses the use of
stereolithography (SLA) rapid~prototype parts within the solid-mold investment~casting process.Mechanical Engineerin
Firm size and export performance: some empirical evidence
This paper uses firm level data collected by the Australian Bureau of Statistics in its Business Longitudinal Survey to help fill the information gap about the characteristics of successful exporters. This study suggests that the main influences on export performance of Australian manufacturing firms may lie with a range of ‘firm-specific’ factors other than size or domestic market share. These potentially include: kind of activity, product design and quality, marketing expertise and the motivation of management.firm size - exports - performance - business - company - exporters
Impact of pig slurry amendments on phosphorus, suspended sediment and metal losses in laboratory runoff boxes under simulated rainfall
peer-reviewedLosses of phosphorus (P) when pig slurry applications to land are followed by a rainfall event or losses from soils with high P contents can contribute to eutrophication of receiving waters. The addition of amendments to pig slurry spread on high P Index soils may reduce P and suspended sediment (SS) losses. This hypothesis was tested at laboratory-scale using runoff boxes under simulated rainfall conditions. Intact grassed soil samples, 100 cm-long, 22.5 cm-wide and 5 cm-deep, were placed in runoff boxes and pig slurry or amended pig slurry was applied to the soil surface. The amendments examined were: (1) commercial grade liquid alum (8% Al2O3) applied at a rate of 0.88:1 [Al:total phosphorus (TP)] (2) commercial-grade liquid ferric chloride (38% FeCl3) applied at a rate of 0.89:1 [Fe:TP] and (3) commercial-grade liquid poly-aluminium chloride (PAC) (10% Al2O3) applied at a rate of 0.72:1 [Al:TP]. The grassed soil was then subjected to three rainfall events (10.3 ± 0.15 mm h−1) at time intervals of 48, 72, and 96 h following slurry application. Each sod received rainfall on 3 occasions. Results across three rainfall events showed that for the control treatment, the average flow weighted mean concentration (FWMC) of TP was 0.61 mg L−1, of which 31% was particulate phosphorus (PP), and the average FWMC of SS was 38.1 mg L−1. For the slurry treatment, there was an average FWMC of 2.2 mg TP L−1, 47% of which was PP, and the average FWMC of SS was 71.5 mg L−1. Ranked in order of effectiveness from best to worst, PAC reduced the average FWMC of TP to 0.64 mg L−1 (42% PP), FeCl3 reduced TP to 0.91 mg L−1 (52% PP) and alum reduced TP to 1.08 mg L−1 (56% PP). The amendments were in the same order when ranked for effectiveness at reducing SS: PAC (74%), FeCl3 (66%) and alum (39%). Total phosphorus levels in runoff plots receiving amended slurry remained above those from soil only, indicating that, although incidental losses could be mitigated by chemical amendment, chronic losses from the high P index soil in the current study could not be reduced.The first author gratefully acknowledges the award of the EMBARK scholarship from
IRCSET to support this study
Reduction and analysis of VLA maps for 281 radio-loud quasars using the UNLV Cray Y-MP supercomputer
The identification of distorted radio-loud quasars provides a potentially very powerful tool for basic cosmological studies. If large morphological distortions are correlated with membership of the quasars in rich clusters of galaxies, optical observations can be used to identify rich clusters of galaxies at large redshifts. Hintzen, Ulvestad, and Owen (1983, HUO) undertook a VLA A array snapshot survey at 20 cm of 123 radio-loud quasars, and they found that among triple sources in their sample, 17 percent had radio axes which were bent more than 20 deg and 5 percent were bent more than 40 deg. Their subsequent optical observations showed that excess galaxy densities within 30 arcsec of 6 low-redshift distorted quasars were on average 3 times as great as those around undistorted quasars (Hintzen 1984). At least one of the distorted quasars observed, 3C275.1, apparently lies in the first-ranked galaxy at the center of a rich cluster of galaxies (Hintzen and Romanishin, 1986). Although their sample was small, these results indicated that observations of distorted quasars could be used to identify clusters of galaxies at large redshifts. The purpose of this project is to increase the available sample of distorted quasars to allow optical detection of a significant sample of quasar-associated clusters of galaxies at large redshifts
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