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

Operational criteria used by professional social workers to assess relationship

Thesis (M.S.)--Boston Universit

Rules of Engagement: design attributes for social interactions

We present a taxonomy for the design of workplace “break” spaces. The taxonomy can be used to identify aspects of current spaces that are either successful or problematic. From this analysis, we demonstrate how the taxonomy can be used to identify opportunities for computer mediated augmentation of spaces, and how such designs can be validated against this taxonomy

Design and development of a novel natural turf shear stability tester

The stability of natural Rugby Union pitches continues to be a recurring problem at all levels of the game. The effects of poor stability are seen when the pitch surface shears under player loading, creating unsightly divots and an uneven and potentially injurious surface. This observed instability is a real concern for many stakeholders, from the groundsmen to the revenue-generating television companies, and is arguably increasing caused by greater popularity of sports, more intensive use of natural turf pitches and advances in player physical conditioning. However, perhaps surprisingly, no objective quantitative mechanical test method currently exists for assessing the shear stability of the natural turf prior to games being played. This paper presents the findings from a (ongoing) research study into the design and development of a prototype turf stability apparatus (‘Turf Tester’). The key aim was to measure the shearing stability of natural and hybrid turf in order to assess a recurring failure problem. In order to be relatable to sporting performance, this failure imitates conditions to simulate player(s) interaction. The prototype and test method was developed with properties suggested from published papers discussing rugby and agronomists’ experience. It was theorized that there was a potential zone susceptible to failure within the top 100 mm of the sports turf. The position of this zone was variable and depended on pitch construction. The prototype was built to explore this variable failure zone using a 50 mm and 100 mm pin that sheared through the soil when a known load was applied to it. Both the Clegg Impact Hammer (CIH) and the rotational traction (RTD) were suggested to be relatable to penetration and shear stability; however, their relatability to the failure zone was an unknown. This paper details the background behind the study, the prototype design and principle, the observed failure mechanisms of sports turf, and presents the results of the prototype apparatus trailed on a range of turf constructions at venues used for the 2015 Rugby World Cup. Data was collected at each venue using Labosport’s Scoreplay system detailing full agronomic classifications and a suite of industry standard player performance tests. The combined data from 13 of the venues provided a powerful data set to evaluate and refine the prototype apparatus, providing validity of its conceptual design. The findings show that the shear tester assessed the upper level of ability of pitches with a 50 mm depth pin and the lower ability with the 100 mm pin. There was some evidence of a relationship to the CIH and RTD, albeit weak, and it was concluded the shear tester was assessing a characteristic of the sport turf not currently measured by standard industry tests currently utilized. The shear tester differentiated between the high stability of the hybrid pitch constructions and the weaker natural pitches. The shear tester rankings for pitch quality also approximated well the ranking from the Scoreplay pitch quality system. Incorporation of the shear tester into routine pitch evaluations could benefit a scoring system approac

Novel field equipment for assessing the stability of natural and hybrid turfs

Natural turf pitches are used for many outdoor sports. Turf is a complex network of interacting organic material, soil textures and water content. Turf is susceptible to damage under large surface forces, caused by intensive player movements in rugby union and football. To assess and monitor surface stability, there needs to be a reliable test method for ground staff and other stakeholders. At present, no turf stability mechanical test method exists that represents player–surface interaction, especially to represent a linear movement across the surface such as in a rugby scrummage. This paper describes the development of a novel device for assessing turf stability. Verification was undertaken in the laboratory on a variety of controlled soil samples, and during a field study. The device measurements were shown to be sensitive to the shear strength of a high clay content soil at varying water content and to the density and type of sandy soils. A programme of field data on high quality pitches suggested a large effect of the turf root reinforcement. A conceptual model of soil failure induced by the device was developed to identify the key soil variables and support experimental data interpretation

Investigating shear stability of rugby union natural turf pitches

The stability of natural Rugby Union pitches continues to be a recurring problem at all levels of the game. The effects of poor turf stability are seen when the pitch surface shears under player loading, creating divots and an uneven surface. However, perhaps surprisingly, there is no objective quantitative mechanical test method for assessing the stability of the natural turf, with regard to shear resistance. This paper details initial work undertaken to assess the effectiveness of current shear testing apparatus in predicting stability for Rugby Union. It has been suggested there are two failure areas in pitch constructions: One on the surface and one deeper in the soil. The results show variability in natural turf constructions, and that current shear test methods are less effective in sandy soils. Penetration readings were relatable to hardness, however shear stability testing requires development

Investigating shear stability of rugby union natural turf pitches

The stability of natural Rugby Union pitches continues to be a recurring problem at all levels of the game. The effects of poor turf stability are seen when the pitch surface shears under player loading, creating divots and an uneven surface. However, perhaps surprisingly, there is no objective quantitative mechanical test method for assessing the stability of the natural turf, with regard to shear resistance. This paper details initial work undertaken to assess the effectiveness of current shear testing apparatus in predicting stability for Rugby Union. It has been suggested there are two failure areas in pitch constructions: One on the surface and one deeper in the soil. The results show variability in natural turf constructions, and that current shear test methods are less effective in sandy soils. Penetration readings were relatable to hardness, however shear stability testing requires development

Design and development of a novel natural turf shear stability tester

The stability of natural Rugby Union pitches continues to be a recurring problem at all levels of the game. The effects of poor stability are seen when the pitch surface shears under player loading, creating unsightly divots and an uneven and potentially injurious surface. This observed instability is a real concern for many stakeholders, from the groundsmen to the revenue-generating television companies, and is arguably increasing caused by greater popularity of sports, more intensive use of natural turf pitches and advances in player physical conditioning. However, perhaps surprisingly, no objective quantitative mechanical test method currently exists for assessing the shear stability of the natural turf prior to games being played. This paper presents the findings from a (ongoing) research study into the design and development of a prototype turf stability apparatus (‘Turf Tester’). The key aim was to measure the shearing stability of natural and hybrid turf in order to assess a recurring failure problem. In order to be relatable to sporting performance, this failure imitates conditions to simulate player(s) interaction. The prototype and test method was developed with properties suggested from published papers discussing rugby and agronomists’ experience. It was theorized that there was a potential zone susceptible to failure within the top 100 mm of the sports turf. The position of this zone was variable and depended on pitch construction. The prototype was built to explore this variable failure zone using a 50 mm and 100 mm pin that sheared through the soil when a known load was applied to it. Both the Clegg Impact Hammer (CIH) and the rotational traction (RTD) were suggested to be relatable to penetration and shear stability; however, their relatability to the failure zone was an unknown. This paper details the background behind the study, the prototype design and principle, the observed failure mechanisms of sports turf, and presents the results of the prototype apparatus trailed on a range of turf constructions at venues used for the 2015 Rugby World Cup. Data was collected at each venue using Labosport’s Scoreplay system detailing full agronomic classifications and a suite of industry standard player performance tests. The combined data from 13 of the venues provided a powerful data set to evaluate and refine the prototype apparatus, providing validity of its conceptual design. The findings show that the shear tester assessed the upper level of ability of pitches with a 50 mm depth pin and the lower ability with the 100 mm pin. There was some evidence of a relationship to the CIH and RTD, albeit weak, and it was concluded the shear tester was assessing a characteristic of the sport turf not currently measured by standard industry tests currently utilized. The shear tester differentiated between the high stability of the hybrid pitch constructions and the weaker natural pitches. The shear tester rankings for pitch quality also approximated well the ranking from the Scoreplay pitch quality system. Incorporation of the shear tester into routine pitch evaluations could benefit a scoring system approac

Reviews

Reviews of Contemporary British Industrial Relations, Human Resource Management and Labour Market Flexibility: Some Current Theories and Controversies, Labour Market Adjustment in New Zealand, Unions Under Economic Development: Private Sector Unions in Papua New Guinea, Women and Part-Time Work in New Zealand and New Impacts on Industrial Relations