Earth-to-orbit transportation for solar power satellites

The cargo transport capability and the cost of space transportation operations for transportation of solar power satellites (SPS) to space are addressed. The history of SPS launch vehicle evolution is shown. Alternative vehicle designs developed include: (1) a parallel burn, crossfeed configuration; (2) single stage to orbit airbreathing/rocket runway takeoff vehicle concept; and (3) a smaller HLLV concept. The smaller HLLV was analyzed to compare the nonrecurring cost benefits of a less challenging development with the recurring cost increases expected due to losses in efficiency associated with smaller vehicle size. The vehicle payload bay size was selected to be adequate to accommodate the SPS transmitter subarrays fully assembled. The resulting vehicle design is compared with the shuttle, the Saturn V, and the reference SPS HLLV. A nonrecurring savings of at least five billion dollars was obtained with a recurring cost penalty of 3% per SPS. The environmental benefits of the small vehicle were deemed more important than the slight increase in upper atmosphere propellant deposition. It is recommended that the small HLLV be adopted as the SPS reference launch system

Emerging SPS Concepts

Four technologies were evaluated to determine their effect on Satellite Power System concepts. Two of these technologies, solid-state power amplifiers and magnetrons, are replacements for the Klystrons used for dc to RF conversion on the satellite. A third technology, laser power transmission, transmits the energy at laser frequencies rather than microwave frequencies. The fourth technology, multibandgap solar cells, has the promise of significantly increased solar to dc conversion efficienty as compared to the reference-concept silicon and gallium arsenide solar cells. The design characteristics of concepts resulting from application of these technologies are summarized

Aquaculture in Jamaica

Jamaica, with its overfish marine resources, has become a major tilapia producer in Latin America led by a small number of large farms practicing tilapia culture with considerable commercial success. Across the country, however, aquaculture is typically practiced by a large number of small-scale fish farmers who own less than 1.0 ha of land. Production is constrained by lack of credit, finite land space and suitable soil type, but larger existing aquaculturists are expanding further for overseas markets. Inspired by pioneering tilapia fish culture demonstration projects funded by the USAID and the goverment of Jamaica, fish culture production rose from a few hundred kg of Oreochromis niloticus in 1977, to about 5000 t of processed fish mainly red hybrid tilapia, in 2000. Most of this quantity was exported to Europe and North America

Fluctuation Scaling, Taylor’s Law, and Crime

Fluctuation scaling relationships have been observed in a wide range of processes ranging from internet router traffic to measles cases. Taylor’s law is one such scaling relationship and has been widely applied in ecology to understand communities including trees, birds, human populations, and insects. We show that monthly crime reports in the UK show complex fluctuation scaling which can be approximated by Taylor’s law relationships corresponding to local policing neighborhoods and larger regional and countrywide scales. Regression models applied to local scale data from Derbyshire and Nottinghamshire found that different categories of crime exhibited different scaling exponents with no significant difference between the two regions. On this scale, violence reports were close to a Poisson distribution (α = 1.057±0.026) while burglary exhibited a greater exponent (α = 1.292±0.029) indicative of temporal clustering. These two regions exhibited significantly different pre-exponential factors for the categories of anti-social behavior and burglary indicating that local variations in crime reports can be assessed using fluctuation scaling methods. At regional and countrywide scales, all categories exhibited scaling behavior indicative of temporal clustering evidenced by Taylor’s law exponents from 1.43±0.12 (Drugs) to 2.094±0081 (Other Crimes). Investigating crime behavior via fluctuation scaling gives insight beyond that of raw numbers and is unique in reporting on all processes contributing to the observed variance and is either robust to or exhibits signs of many types of data manipulation

Calvinism, Proslavery and James Albert Ukawsaw Gronniosaw

This is the author accepted manuscript. The final version is available from Taylor & Francis via the DOI in this recordIn the autobiography of James Albert Ukawsaw Gronniosaw, the first black author to be published in Britain, slavery was represented at best neutrally and at worst as spiritually and socially beneficial. Re-reading Gronniosaw's Narrative in the context of the Calvinist and Dutch Reformed confessional networks facilitating its composition and publication enables us to understand how and why a former slave would produce a text apparently advocating proslavery ideology. Gronniosaw's case demonstrates that black intellectuals, far from being solely concerned with abolitionism, participated in a broad array of political, religious and social movements during the eighteenth century, occasionally even those that supported slavery

A radical change of heart: Robert Wedderburn's last word on slavery

This is the author accepted manuscript. The final version is available from Taylor & Francis via the DOI in this recordThis article introduces to modern scholarship An Address to Lord Brougham and Vaux, a recently rediscovered anti-abolitionist tract by the black radical author and orator Robert Wedderburn, written in 1831, towards the end of his life. It gives a brief biography of the author and introduces some of the key themes that characterised his earlier work. Questions of authenticity and authority are raised in the context of earlier appropriations of Wedderburn's already fluid authorial identity and the specific social and political circumstances surrounding the text's publication. A transcript of the text is provided with some minor elisions

The Royal Slave: Nobility, Diplomacy and the “African Prince” in Britain, 1748–1752

This is the author acepted manuscript. The final version is available from Cambridge University Press via the DOI in this recordWilliam Ansah Sessarakoo, the son of a powerful Fante slave trader on the Gold Coast, was tricked and sold into slavery in Barbados by a British ship’s captain during the 1740s. He was emancipated and brought to Britain in 1748, where he enjoyed a brief period of national celebrity before returning to the Gold Coast in 1750. This paper examines the specific political and cultural circumstances surrounding his remarkable journey, through the lens of the media generated about him during his time in Britain. It demonstrates that the most extensive contemporaneous account of Sessarakoo’s story, The Royal African, was in reality an attempt to generate popular support for a moribund Royal African Company and incorporate slave trading into narratives of national identity, based on notions of economic responsibility and honour. Adhering to conventions typified in Thomas Southerne’s stage adaptation of Oroonoko, further popular representations of Sessarakoo emphasised his aristocratic status and putatively inherited ‘noble’ characteristics. In doing so, they emphasised perceived differences between him and the majority of African peoples, who were deemed suitable for enslavement. The paper closes with an examination of some of the effects of Sessarakoo’s visit on Euro-African trade and diplomacy on the Gold Coast

Slavery and the birth of working-class racism in England, 1814–1833. The Alexander Prize Essay

This is the author accepted manuscript. The final version is available from Cambridge University Press via the DOI in this recordThis paper examines racist discourse in radical print culture from the end of the Napoleonic Wars to the passing of the Abolition of Slavery Act in Britain. Acknowledging the heterogeneity of working-class ideology during the period, it demonstrates that some radical writers actively sought to dehumanise enslaved and free black people as a means of promoting the interests of the white working class in England. It argues that by promoting a particular understanding of English racial superiority, radical intellectuals such as John Cartwright, William Cobbett, and Richard Carlile were able to criticise the diversion of humanitarian resources and attention away from exploited industrial workers and towards enslaved black people in the British West Indies or unconverted free Africans. Moreover, by presenting a supposedly inferior racial antitype, they sought to minimise the social boundaries that were used to disenfranchise English working men and reinforce their own, seemingly precarious, claims to parliamentary reform and meaningful political representation

Aquaculture in Jamaica

Jamaica, with its overfish marine resources, has become a major tilapia producer in Latin America led by a small number of large farms practicing tilapia culture with considerable commercial success. Across the country, however, aquaculture is typically practiced by a large number of small-scale fish farmers who own less than 1.0 ha of land. Production is constrained by lack of credit, finite land space and suitable soil type, but larger existing aquaculturists are expanding further for overseas markets. Inspired by pioneering tilapia fish culture demonstration projects funded by the USAID and the goverment of Jamaica, fish culture production rose from a few hundred kg of Oreochromis niloticus in 1977, to about 5000 t of processed fish mainly red hybrid tilapia, in 2000. Most of this quantity was exported to Europe and North America.Aquaculture development, Aquaculture enterprises, Fish culture, Jamaica, Oreochromis niloticus, Oreochromis mossambicus, Colossoma macropomus, Macrobrachium rosenbergii