1,739,447 research outputs found
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
Solar sail capture trajectories at Mercury
No full textMercury is an ideal environment for future planetary exploration by solar sail since it has proved difficult to reach with conventional propulsion and hence remains largely unexplored. In addition, its proximity to the Sun provides a solar sail acceleration of order ten times the sail characteristic acceleration at 1 AU. Conventional capture techniques are shown to be unsuitable for solar sails and a new method is presented. It is shown that capture is bound by upper and lower limits on the orbital elements of the approach orbit and that failure to be within limits results in a catastrophic collision with the planet. These limits are presented for a range of capture inclinations and sail characteristic accelerations. It is found that sail hyperbolic excess velocity is a critical parameter during capture at Mercury, with only a narrow allowed band in order to avoid collision with the planet. The new capture methodis demonstrated for a Mercury sample return mission
Author Under Sail The Imagination of Jack London, 1902-1907
No full textIn this second volume of Author Under Sail Jay Williams investigates the life of Jack London as a professional writer at the turn of the 1900s, as his publications spanned The Call of the Wild to The Iron Heel and The Road. While documenting key life events, especially his rising fame, this biography explores London's necessity to illustrate the inner workings of his own vast imagination through his socialist essays and fiction.Cover -- Title Page -- Copyright Page -- Contents -- Acknowledgments -- Introduction -- 1. Howl, O Heav'nly Muse! -- 2. Jesus in the Theater of Socialism -- 3. Jack London's Place in American Literature -- 4. Theater of War, Theater at Home -- 5. Revolution, Evolution, and the Scene of Writing -- 6. The Jack London Show Goes on the Road -- 7. Red Atavisms and Revolution -- 8. Earthquake Apocalypse and Building the City, Boat, and House Beautiful -- 9. The Future of Socialism and the Death of the Individual -- 10. The Road Never Ends -- Notes -- Bibliography -- IndexIn this second volume of Author Under Sail Jay Williams investigates the life of Jack London as a professional writer at the turn of the 1900s, as his publications spanned The Call of the Wild to The Iron Heel and The Road. While documenting key life events, especially his rising fame, this biography explores London's necessity to illustrate the inner workings of his own vast imagination through his socialist essays and fiction.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
Optimisation of solar sail interplanetary heteroclinic connections
No full textThis paper investigates time-optimal solar sail trajectories between displaced Libration Point Orbits (LPOs) of different circular restricted three-body systems. Key in the investigations is the search for transfers that require little steering ef-fort to enable the transfers with low control authority solar sail-like devices such as SpaceChips. Two transfers are considered: 1) from an Earth-L2 Halo orbit to a Mars-L1 Halo orbit and 2) from an Earth-L1 Halo orbit to a Mercury-L2 Halo or-bit. For both transfers the optimal control problem is derived and solved with a direct pseudospectral method. For a sail performance comparable to that of NASA’s Sunjammer sail, the results show transfers that require very little steer-ing effort: the sail acceleration vector can be bounded to a cone with a half angle of 5 deg (Earth-Mars) or even 2.5 deg (Earth-Mercury). These transfers can serve a range of novel solar sail applications covering the entire spectrum of sail length-scales: micro-sized SpaceChips could establish a continuous Earth-Mars communication link, a traditional-sized sail provides opportunities for in-situ observations of Mercury and a future kilometer-sized sail could create an Earth-Mars cargo transport gateway for human exploration of Mars
GeoSail : an elegant solar sail demonstration mission
No full textIn this paper a solar sail magnetotail mission concept was examined. The 43-m square solar sail is used to providethe required propulsion for continuous sun-synchronous apse-line precession. The main driver in this mission was found to be the reduction of launch mass and mission cost while enabling a nominal duration of 2 years within the framework of a demonstration mission. It was found that the mission concept provided an excellent solar sail technology demonstration option. The baseline science objectives and engineering goals were addressed, and mission analysis for solar sail, electric, and chemical propulsion performed. Detailed subsystems were defined for each propulsion system and it was found that the optimum propulsion system is solar sailing. A detailed tradeoff as to the effect of spacecraft and sail technology levels, and requirements, on sail size is presented for the first time. The effect of, for example, data acquisition rate and RF output power on sail size is presented, in which it is found that neither have a significant effect. The key sail technology requirements have been identified through a parametric analysis
Approximate closed-form solution for solar sail spiral trajectories with sail degradation
Full text linkSolar sails have long been considered as a means of enabling new high-energy missions, such as solar polar orbiter, planetary sample return and heliopause probes, along with families of highly non-Keplerian orbits for space weather and Earth observation missions, as reviewed in Refs 1 and 2. While most prior analysis of solar sail orbital dynamics assumes that the optical properties of the sail are time-invariant, it is expected that the sail membrane will slowly degrade due to cumulative, long-term exposure to solar radiation. The effect of such degradation was investigated in some detail by Dachwald and co-workers through a combination of modelling and numerical optimization. 3,4. As expected, it was found that degradation has an impact on the trip time of solar sails to target orbits and the ability of solar sails to realize non-Keplerian orbits. In this Note, an approximate closed-form solution is presented for solar sail spiral trajectories with sail degradation. Since exposure to the space environment is cumulative, the impact of degradation on the sail thrust magnitude forms an integral function over the spiral duration. The time evolution of the solar sail spiral trajectory is therefore described by an integro-differential equation, which for this problem does not apparently possess an explicit closed-form solution. However, it is possible to obtain an implicit solution to the problem which provides an approximate representation of the evolution of the solar sail spiral trajectory. This allows an initial estimation of the impact of sail degradation on mission performance to be made. Limits are also found which bound the motion of the solar sail to an annulus, whose inner and outer radii are defined by the sail degradation rate. These limits correspond to the asymptotic behaviour of the solar sail where the sail becomes completely absorbing, the transverse component of sail thrust vanishes and the spiral terminates. In addition, it is shown that the optimal fixed sail pitch angle required to maximize the inner and outer radius of the annulus differs from the usual sail pitch angle which maximizes the transverse component of sail thrust. For a solar sail subject to degradation, the optimum fixed sail pitch angle must trade-off maximising the transverse component of sail thrust while minimising the projected sail area exposed to solar radiation. Finally, while these asymptotic limits of motion represent an operational constraint, they could in principle be used as a means of enabling entirely passive orbit transfer. For example, a small, low cost solar sail with a passively fixed pitch angle could deliver a payload onto a quasi-circular spiral trajectory. If the sail film is engineered to degrade at a certain rate, the asymptotic orbit the sail winds onto can then be chosen a priori. The solar sail will then perform a near circle-to-circle transfer, in principle satisfying a simple two-point boundary value problem, but using only a passively fixed sail pitch angle. Such a mode of transfer could be used to deliver payloads to given heliocentric orbits, for example for space physics applications
Solar sail mission applications and future advancement
No full textSolar sailing has long been envisaged as an enabling technology. The promise of open-ended missions allows consideration of radically new trajectories and the delivery of spacecraft to previously unreachable or unsustainable observation outposts. A mission catalogue is presented of an extensive range of potential solar sail applications, allowing identification of the key features of missions which are enabled, or significantly enhance, through solar sail propulsion. Through these considerations a solar sail application-pull technology development roadmap is established, using each mission as a technology stepping-stone to the next. Having identified and developed a solar sail application-pull technology development roadmap, this is incorporated into a new vision for solar sailing. The development of new technologies, especially for space applications, is high-risk. The advancement difficulty of low technology readiness level research is typically underestimated due to a lack of recognition of the advancement degree of difficulty scale. Recognising the currently low technology readiness level of traditional solar sailing concepts, along with their high advancement degree of difficulty and a lack of near-term applications a new vision for solar sailing is presented which increases the technology readiness level and reduces the advancement degree of difficulty of solar sailing. Just as the basic principles of solar sailing are not new, they have also been long proven and utilised in spacecraft as a low-risk, high-return limited-capability propulsion system. It is therefore proposed that this significant heritage be used to enable rapid, near-term solar sail future advancement through coupling currently mature solar sail, and other, technologies with current solar sail technology developments. As such the near-term technology readiness level of traditional solar sailing is increased, while simultaneously reducing the advancement degree of difficulty along the solar sail application-pull technology development roadmap
Displaced solar sail orbits : dynamics and applications
No full textWe consider displaced periodic orbits at linear order in the circular restricted Earth-Moon system, where the third massless body is a solar sail. These highly non-Keplerian orbits are achieved using an extremely small sail acceleration. Prior results have been developed by using an optimal choice of the sail pitch angle, which maximises the out-of-plane displacement. In this paper we will use solar sail propulsion to provide station-keeping at periodic orbits around the libration points using small variations in the sail's orientation. By introducing a first-order approximation, periodic orbits are derived analytically at linear order. These approximate analytical solutions are utilized in a numerical search to determine displaced periodic orbits in the full nonlinear model. Applications include continuous line-of-sight communications with the lunar poles
Potential effects of optical solar sail degredation on trajectory design
No full textThe optical properties of the thin metalized polymer films that are projected for solar sails are assumed to be affected by the erosive effects of the space environment. Their degradation behavior in the real space environment, however, is to a considerable degree indefinite, because initial ground test results are controversial and relevant inspace tests have not been made so far. The standard optical solar sail models that are currently used for trajectory design do not take optical degradation into account, hence its potential effects on trajectory design have not been investigated so far. Nevertheless, optical degradation is important for high-fidelity solar sail mission design, because it decreases both the magnitude of the solar radiation pressure force acting on the sail and also the sail control authority. Therefore, we propose a simple parametric optical solar sail degradation model that describes the variation of the sail film's optical coefficients with time, depending on the sail film's environmental history, i.e., the radiation dose. The primary intention of our model is not to describe the exact behavior of specific film-coating combinations in the real space environment, but to provide a more general parametric framework for describing the general optical degradation behavior of solar sails. Using our model, the effects of different optical degradation behaviors on trajectory design are investigated for various exemplary missions
Upwind sail aerodynamics: A RANS numerical investigation validated with wind tunnel pressure measurements
Full text linkThe aerodynamics of a sailing yacht with different sail trims are presented, derived from simulations performed using computational fluid dynamics. A Reynolds-averaged Navier-Stokes approach was used to model sixteen sail trims first tested in a wind tunnel, where the pressure distributions on the sails were measured. An original approach was employed by using two successive simulations: the first one on a large domain to model the blockage due to the wind tunnel walls and the sails model, and a second one on a smaller domain to model the flow around the sails model. A verification and validation of the computed aerodynamic forces and pressure distributions was performed. The computed pressure distribution is shown to agree well with the measured pressures. The sail surface pressure was correlated with the increase of turbulent viscosity in the laminar separation bubble, the flow reattachment and the trailing edge separation. The drive force distribution on both sails showed that the fore part of the genoa (fore sail) provides the majority of the drive force and that the effect of the aft sail is mostly to produce an upwash effect on the genoa. An aerodynamic model based on potential flow theory and a viscous correction is proposed. This model, with one free parameter to be determined, is shown to fit the results better than the usual form drag and induced drag only, even if no friction drag is explicitly considered. (C) 2012 Elsevier Inc. All rights reserved.</p
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