WorldWideScience

Sample records for sails

  1. Solar Sailing

    Science.gov (United States)

    Johnson, Les

    2009-01-01

    Solar sailing is a topic of growing technical and popular interest. Solar sail propulsion will make space exploration more affordable and offer access to destinations within (and beyond) the solar system that are currently beyond our technical reach. The lecture will describe solar sails, how they work, and what they will be used for in the exploration of space. It will include a discussion of current plans for solar sails and how advanced technology, such as nanotechnology, might enhance their performance. Much has been accomplished recently to make solar sail technology very close to becoming an engineering reality and it will soon be used by the world s space agencies in the exploration of the solar system and beyond. The first part of the lecture will summarize state-of-the-art space propulsion systems and technologies. Though these other technologies are the key to any deep space exploration by humans, robots, or both, solar-sail propulsion will make space exploration more affordable and offer access to distant and difficult destinations. The second part of the lecture will describe the fundamentals of space solar sail propulsion and will describe the near-, mid- and far-term missions that might use solar sails as a propulsion system. The third part of the lecture will describe solar sail technology and the construction of current and future sailcraft, including the work of both government and private space organizations.

  2. Solar sail deployment experiment

    OpenAIRE

    Shimose, Shigeru; 下瀬 滋

    2006-01-01

    Solar Sail move by receiving momentum of photons in sunlight. This paper presents results of some Spin-Stabilized Solar Sail deployment experiment. ISAS has successfully deployed, for the first time in the world, the polyimide Solar Sail taking advantage of centrifugal force in space. Based on this result, the new deployment mechanism is being developed which retracts the 50 m diameter sail.

  3. Unconventional Solar Sailing

    Science.gov (United States)

    Ceriotti, Matteo

    The idea of exploiting solar radiation pressure for space travel, or solar sailing, is more than a 100 years old, and yet most of the research thus far has considered only a limited number of sail configurations. However solar sails do not have to be inertially-pointing squares, spin-stabilised discs or heliogyros: there is a range of different configurations and concepts that present some advantageous features. This chapter will show and discuss three non-conventional solar sail configurations and their applications. In the first, the sail is complemented by an electric thruster, resulting in a hybrid-propulsion spacecraft which is capable to hover above the Earth's Poles in a stationary position (pole-sitter). The second concept makes use of a variable-geometry pyramidal sail, naturally pointing towards the sun, to increase or decrease the orbit altitude without the need of propellant or attitude manoeuvres. Finally, the third concept shows that the orbit altitude can also be changed, without active manoeuvres or geometry change, if the sail naturally oscillates synchronously with the orbital motion. The main motivation behind these novel configurations is to overcome some of the engineering limitations of solar sailing; the resulting concepts pose some intriguing orbital and attitude dynamics problems, which will be discussed.

  4. Sports medicine and sailing.

    Science.gov (United States)

    Allen, J B

    1999-02-01

    Although there is little epidemiologic data in the sport of sailing, the identification of important trends can assist the clinician in successful evaluation, treatment, and rehabilitation of the individual. It appears that like other sports, the majority of injuries encountered are of the microtraumatic or overuse type. An understanding of biomechanics, the overload injury, and the sport of sailing will allow the development of a comprehensive rehabilitation program to ensure the optimal performance and safety of the sailor.

  5. UltraSail Solar Sail Flight Experiment Project

    Data.gov (United States)

    National Aeronautics and Space Administration — CU Aerospace and its University of Illinois teammate propose the design, sub-component fabrication and preliminary test of an UltraSail "Cubesat" 20 m2 solar sail...

  6. Lightweight Light Sail Propulsion Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The areal density of solar sails and laser sails is large due to the heavy support structure made of Mylar, Kapton or CP-1. Replacing this support structure with...

  7. The aerodynamics of sailing apparel

    NARCIS (Netherlands)

    Jansen, A.J.; Van Deursen, B.; Howe, C.

    2012-01-01

    The paper presents the effect of changes in sailing apparel on aerodynamic drag, starting from the assumption that drag reduction of sailing apparel will increase the speed of an Olympic class sailing boat (in this case the Laser, a single-handed Olympic dinghy), mainly on upwind courses. Due to the

  8. Sailing New Seas

    Science.gov (United States)

    1998-03-01

    forum. The Navy needs a better forum fo r ideas . One can be built on the Internet . That job should be done now. Who among us will do it? The Navy...For coevolution to occur, diversity of ideas must be catalyzed by communication (diversity wi thout 86 Sail ing New Seas communicatio n among

  9. Solar sail mission design

    Energy Technology Data Exchange (ETDEWEB)

    Leipold, M.

    2000-02-01

    The main subject of this work is the design and detailed orbit transfer analysis of space flight missions with solar sails utilizing solar pressure for primary propulsion. Such a sailcraft requires ultra-light weight, gossamer-like deployable structures and materials in order to effectively utilize the transfer of momentum of solar photons. Different design concepts as well as technological elements for solar sails are considered, and an innovative design of a deployable sail structure including new methods for sail folding and unfolding is presented. The main focus of this report is on trajectory analysis, simulation and optimization of planetocentric as well as heliocentric low-thrust orbit transfers with solar sails. In a parametric analysis, geocentric escape spiral trajectories are simulated and corresponding flight times are determined. In interplanetary space, solar sail missions to all planets in our solar system as well as selected minor bodies are included in the analysis. Comparisons to mission concepts utilizing chemical propulsion as well as ion propulsion are included in order to assess whether solar sailing could possibly enhance or even enable this mission. The emphasis in the interplanetary mission analysis is on novel concepts: a unique method to realize a sun-synchronous Mercury orbiter, fast missions to the outer planets and the outer heliosphere applying a ''solar photonic assist'', rendezvous and sample return missions to asteroids and comets, as well as innovative concepts to reach unique vantage points for solar observation (''Solar Polar Orbiter'' and ''Solar Probe''). Finally, a propellant-less sailcraft attitude control concept using an external torque due to solar pressure is analyzed. Examples for sail navigation and control in circular Earth orbit applying a PD-control algorithm are shown, illustrating the maneuverability of a sailcraft. (orig.) [German] Gegenstand dieser

  10. SAIL: automating interlibrary loan.

    Science.gov (United States)

    Lacroix, E M

    1994-04-01

    The National Library of Medicine (NLM) initiated the System for Automated Interlibrary Loan (SAIL) pilot project to study the feasibility of using imaging technology linked to the DOCLINE system to deliver copies of journal articles. During the project, NLM converted a small number of print journal issues to electronic form, linking the captured articles to the MEDLINE citation unique identifier. DOCLINE requests for these journals that could not be filled by network libraries were routed to SAIL. Nearly 23,000 articles from sixty-four journals recently selected for indexing in Index Medicus were scanned to convert them to electronic images. During fiscal year 1992, 4,586 scanned articles were used to fill 10,444 interlibrary loan (ILL) requests, and more than half of these were used only once. Eighty percent of all the articles were not requested at all. The total cost per article delivered was $10.76, substantially more than it costs to process a photocopy request. Because conversion costs were the major component of the total SAIL cost, and most of the articles captured for the project were not requested, this model was not cost-effective. Data on SAIL journal article use was compared with all ILL requests filled by NLM for the same period. Eighty-eight percent of all articles requested from NLM were requested only once. The results of the SAIL project demonstrated that converting journal articles to electronic images and storing them in anticipation of repeated requests would not meet NLM's objective to improve interlibrary loan.

  11. UltraSail CubeSat Solar Sail Flight Experiment

    Science.gov (United States)

    Carroll, David; Burton, Rodney; Coverstone, Victoria; Swenson, Gary

    2013-01-01

    UltraSail is a next-generation, highrisk, high-payoff sail system for the launch, deployment, stabilization, and control of very large (km2 class) solar sails enabling high payload mass fractions for interplanetary and deep space spacecraft. UltraSail is a non-traditional approach to propulsion technology achieved by combining propulsion and control systems developed for formation- flying microsatellites with an innovative solar sail architecture to achieve controllable sail areas approaching 1 km2, sail subsystem area densities approaching 1 g/m2, and thrust levels many times those of ion thrusters used for comparable deep space missions. UltraSail can achieve outer planetary rendezvous, a deep-space capability now reserved for high-mass nuclear and chemical systems. There is a twofold rationale behind the UltraSail concept for advanced solar sail systems. The first is that sail-andboom systems are inherently size-limited. The boom mass must be kept small, and column buckling limits the boom length to a few hundred meters. By eliminating the boom, UltraSail not only offers larger sail area, but also lower areal density, allowing larger payloads and shorter mission transit times. The second rationale for UltraSail is that sail films present deployment handling difficulties as the film thickness approaches one micrometer. The square sail requires that the film be folded in two directions for launch, and similarly unfolded for deployment. The film is stressed at the intersection of two folds, and this stress varies inversely with the film thickness. This stress can cause the film to yield, forming a permanent crease, or worse, to perforate. By rolling the film as UltraSail does, creases are prevented. Because the film is so thin, the roll thickness is small. Dynamic structural analysis of UltraSail coupled with dynamic control analysis shows that the system can be designed to eliminate longitudinal torsional waves created while controlling the pitch of the blades

  12. Advances in solar sailing

    CERN Document Server

    Third International Symposium on Solar Sailing

    2014-01-01

    Hosted by the Advanced Space Concepts Laboratory within the department of Mechanical and Aerospace Engineering of the University of Strathclyde, the third International Symposium on Solar Sailing was held in McCance Building at 16 Richmond Street, Glasgow, between 11 and 13 June 2013. The symposium attracted over 90 delegates from19 different counties, bringing together international experts from across the globe to discuss funded solar sail flight programs alongside on-going technology development and testing programs. The symposium also provided a forum for the discussion of enabling technologies, new application concepts, materials and structural concepts, space environmental effects, dynamics, navigation, control, and much more. This volume contains the unabridged symposium proceedings, in the gathered experts own words. As symposium chair, I thank our partners at Scottish Enterprise and L’Garde, Inc., the symposium’s gold sponsor, for their support in realising this symposium.

  13. Sailing: Cognition, action, communication

    Directory of Open Access Journals (Sweden)

    Thora Tenbrink

    2017-12-01

    Full Text Available How do humans perceive and think about space, and how can this be represented adequately? For everyday activities such as locating objects or places, route planning, and the like, many insights have been gained over the past few decades, feeding into theories of spatial cognition and frameworks for spatial information science. In this paper, we explore sailing as a more specialized domain that has not yet been considered in this way, but has a lot to offer precisely because of its peculiarities. Sailing involves ways of thinking about space that are not normally required (or even acquired in everyday life. Movement in this domain is based on a combination of external forces and internal (human intentions that impose various kinds of directionality, affecting local action as well as global planning. Sailing terminology is spatial to a high extent, and involves a range of concepts that have received little attention in the spatial cognition community. We explore the area by focusing on the core features of cognition, action, and communication, and suggest a range of promising future areas of research in this domain as a showcase of the fascinating flexibility of human spatial cognition.

  14. The aerodynamics of sailing apparel

    OpenAIRE

    Jansen, Arjen; van Deursen, Bas; Howe, Carrie

    2012-01-01

    The paper presents the effect of changes in sailing apparel on aerodynamic drag, starting from the assumption that drag reduction of sailing apparel will increase the speed of an Olympic class sailing boat (in this case the Laser, a single-handed Olympic dinghy), mainly on upwind courses. Due to the fact that literature on this specific subject is non-existent, a theoretical framework on hydrodynamic and aerodynamic drag of the sailing boat and sailor had to be set-up to provide us with ball ...

  15. Comprehensive Solar Sail Simulation Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Solar sails as a propulsive device have several potential applications: providing access to previously inaccessible orbits, longer mission times, and increased...

  16. NanoSail-D: A Solar Sail Demonstration Mission

    Science.gov (United States)

    Johnson, Les; Whorton, Mark; Heaton, Andy; Pinson, robin; Laue, Greg; Adams, Charles

    2009-01-01

    During the past decade, within the United States, NASA Marshall Space Flight Center (MSFC) was heavily engaged in the development of revolutionary new technologies for in-space propulsion. One of the major in-space propulsion technologies developed was a solar sail propulsion system. Solar sail propulsion uses the solar radiation pressure exerted by the momentum transfer of reflected photons to generate a net force on a spacecraft. To date, solar sail propulsion systems have been designed for large spacecraft in the tens to hundreds of kilograms mass range. Recently, however, MSFC has been investigating the application of solar sails for small satellite propulsion. Likewise, NASA Ames Research Center (ARC) has been developing small spacecraft missions that have a need for amass-efficient means of satisfying deorbit requirements. Hence, a synergistic collaboration was established between these two NASA field Centers with the objective of conducting a flight demonstration of solar sail technologies for small satellites. The NanoSail-D mission flew onboard the ill-fated Falcon Rocket launched August 2, 2008, and, due to the failure of that rocket, never achieved orbit. The NanoSail-D flight spare is ready for flight and a suitable launch arrangement is being actively pursued. Both the original sailcraft and the flight spare are hereafter referred to as NanoSail-D. The sailcraft consists of a sail subsystem stowed in a three-element CubeSat. Shortly after deployment of the NanoSail-D, the solar sail will deploy and mission operations will commence. This demonstration flight has two primary technical objectives: (1) to successfully stow and deploy the sail and (2) to demonstrate deorbit functionality. Given a near-term opportunity for launch on Falcon, the project was given the challenge of delivering the flight hardware in 6 mo, which required a significant constraint on flight system functionality. As a consequence, passive attitude stabilization of the spacecraft

  17. Relativistic Light Sails

    Energy Technology Data Exchange (ETDEWEB)

    Kipping, David, E-mail: dkipping@astro.columbia.edu [Department of Astronomy, Columbia University, 550 W. 120th St., New York, NY 10027 (United States)

    2017-06-01

    One proposed method for spacecraft to reach nearby stars is by accelerating sails using either solar radiation pressure or directed energy. This idea constitutes the thesis behind the Breakthrough Starshot project, which aims to accelerate a gram-mass spacecraft up to one-fifth the speed of light toward Proxima Centauri. For such a case, the combination of the sail’s low mass and relativistic velocity renders previous treatments incorrect at the 10% level, including that of Einstein himself in his seminal 1905 paper introducing special relativity. To address this, we present formulae for a sail’s acceleration, first in response to a single photon and then extended to an ensemble. We show how the sail’s motion in response to an ensemble of incident photons is equivalent to that of a single photon of energy equal to that of the ensemble. We use this principle of ensemble equivalence for both perfect and imperfect mirrors, enabling a simple analytic prediction of the sail’s velocity curve. Using our results and adopting putative parameters for Starshot , we estimate that previous relativistic treatments underestimate the spacecraft’s terminal velocity by ∼10% for the same incident energy. Additionally, we use a simple model to predict the sail’s temperature and diffraction beam losses during the laser firing period; this allows us to estimate that, for firing times of a few minutes and operating temperatures below 300°C (573 K), Starshot will require a sail that absorbs less than one in 260,000 photons.

  18. Relativistic Light Sails

    Science.gov (United States)

    Kipping, David

    2017-06-01

    One proposed method for spacecraft to reach nearby stars is by accelerating sails using either solar radiation pressure or directed energy. This idea constitutes the thesis behind the Breakthrough Starshot project, which aims to accelerate a gram-mass spacecraft up to one-fifth the speed of light toward Proxima Centauri. For such a case, the combination of the sail’s low mass and relativistic velocity renders previous treatments incorrect at the 10% level, including that of Einstein himself in his seminal 1905 paper introducing special relativity. To address this, we present formulae for a sail’s acceleration, first in response to a single photon and then extended to an ensemble. We show how the sail’s motion in response to an ensemble of incident photons is equivalent to that of a single photon of energy equal to that of the ensemble. We use this principle of ensemble equivalence for both perfect and imperfect mirrors, enabling a simple analytic prediction of the sail’s velocity curve. Using our results and adopting putative parameters for Starshot, we estimate that previous relativistic treatments underestimate the spacecraft’s terminal velocity by ˜10% for the same incident energy. Additionally, we use a simple model to predict the sail’s temperature and diffraction beam losses during the laser firing period; this allows us to estimate that, for firing times of a few minutes and operating temperatures below 300°C (573 K), Starshot will require a sail that absorbs less than one in 260,000 photons.

  19. Ice sails of the Karakoram

    Science.gov (United States)

    Mayer, Christoph; Evatt, Geoffrey W.; Mallinson, Amy; Abrahams, I. David; Heil, Matthias; Nicholson Nicholson, Lindsey; Fowler, Andrew; Lambrecht, Astrid

    2017-04-01

    Ice sails are clean ice features that protrude from the surface of debris covered glaciers, and can grow to more than 25 m in elevation. Observations of these features date back to the first exploration of the glaciers and mountains in the Karakoram (in 1864), where they seem to occur preferentially. Even though melt rates beneath supraglacial debris and of clean ice should be rather different, ice sails can exist in equilibrium for decades. However, no detailed scientific analysis of ice sails has been carried out until now. The apparent restriction of ice sail existence to high elevation, dry atmosphere and long and flat debris covered glaciers, suggests that they require low debris thickness and a high evaporative heat flux for survival. We postulate that ice sails can develop from one of two mechanisms, both of which require clean ice to be surrounded by debris covered ice, where the debris layer is shallow enough for the ice beneath it to melt faster than the clean ice, i.e. typical debris thicknesses of less than 5-10 cm. Our image analysis confirms that ice sails can persist for decades. Debris layer thickening eventually causes a reversal in the relative melt rates and the ice sails submerge back into the glacier. During their stable phase, the slope of the ice sail faces constantly adjusts to the available melt energy, so that a steady state with the surrounding ice melt can be reached. This can be demonstrated by application of an energy balance model and use of the well-known Östrem-curve for sub-debris ice melt.

  20. Status of Solar Sail Technology Within NASA

    Science.gov (United States)

    Johnson, Les; Young, Roy; Montgomery, Edward; Alhorn, Dean

    2010-01-01

    In the early 2000s, NASA made substantial progress in the development of solar sail propulsion systems for use in robotic science and exploration of the solar system. Two different 20-m solar sail systems were produced and they successfully completed functional vacuum testing in NASA Glenn Research Center's (GRC's) Space Power Facility at Plum Brook Station, Ohio. The sails were designed and developed by ATK Space Systems and L Garde, respectively. The sail systems consist of a central structure with four deployable booms that support the sails. These sail designs are robust enough for deployment in a one-atmosphere, one-gravity environment and were scalable to much larger solar sails perhaps as large as 150 m on a side. Computation modeling and analytical simulations were also performed to assess the scalability of the technology to the large sizes required to implement the first generation of missions using solar sails. Life and space environmental effects testing of sail and component materials were also conducted. NASA terminated funding for solar sails and other advanced space propulsion technologies shortly after these ground demonstrations were completed. In order to capitalize on the $30M investment made in solar sail technology to that point, NASA Marshall Space Flight Center (MSFC) funded the NanoSail-D, a subscale solar sail system designed for possible small spacecraft applications. The NanoSail-D mission flew on board the ill-fated Falcon-1 Rocket launched August 2, 2008, and due to the failure of that rocket, never achieved orbit. The NanoSail-D flight spare will be flown in the Fall of 2010. This paper will summarize NASA's investment in solar sail technology to-date and discuss future opportunities

  1. Solar Sailing is not Science Fiction Anymore

    Science.gov (United States)

    Alhorn, Dean C.

    2010-01-01

    Over 400 years ago Johannes Kepler envisioned the use of sunlight to propel a spacecraft. Just this year, a solar sail was deployed in orbit for the first time and proved that a spacecraft could effectively use a solar sail for propulsion. NASA's first nano-class solar sail satellite, NanoSail-D was designed and developed in only four months. Although the first unit was lost during the Falcon 1 rocket failure in 2008, the second flight unit has been refurbished and is waiting to be launched later this year. NanoSail-D will further the research into solar sail enabled spacecraft. It will be the first of several more sail enabled spacecraft to be launch in the next few years. FeatherSail is the next generation nano-class sail spacecraft being designed with the goal to prove low earth orbit operational capabilities. Future solar sail spacecraft will require novel ideas and innovative research for the continued development of space systems. One such pioneering idea is the Small Multipurpose Advanced Reconfigurable Technology (SMART) project. The SMART technology has the potential to revolutionize spacecraft avionics. Even though solar sailing is currently in its infancy, the next decade will provide great opportunities for research into sailing in outer space.

  2. Sailing comfort through axe bow

    NARCIS (Netherlands)

    Verdult, E.

    2012-01-01

    Every year, the Royal Netherlands Sea Rescue Institution (KNRM) heads out to sea 2000 times to rescue people. In conditions with high waves, the lifeboats hit the water so hard that the crew have diffilty keeping upright in the pilot house. Sailing slowly is therefore the only option. But the boats

  3. Flying on Sun Shine: Sailing in Space

    Energy Technology Data Exchange (ETDEWEB)

    Alhorn, Dean (NASA, Marshall Space Flight Center)

    2012-03-28

    On January 20th, 2011, NanoSail-D successfully deployed its sail in space. It was the first solar sail vehicle to orbit the earth and the second sail ever unfurled in space. The 10m2 sail, deployment mechanism and electronics were packed into a 3U CubeSat with a volume of about 3500cc. The NanoSail-D mission had two objectives: eject a nanosatellite from a minisatellite; deploy its sail from a highly compacted volume to validate large structure deployment and potential de-orbit technologies. NanoSail-D was jointly developed by NASA's Marshall Space Flight Center and Ames Research Center. The ManTech/NeXolve Corporation provided key sail design support. NanoSail-D is managed by Marshall and jointly sponsored by the Army Space and Missile Defense Command, the Space Test Program, the Von Braun Center for Science and Innovation and Dynetics Inc. The presentation will provide insights into sailcraft advances and potential missions enabled by this emerging in-space propulsion technology.

  4. Developments of an Interactive Sail Design Method

    Directory of Open Access Journals (Sweden)

    S. M. Malpede

    2000-01-01

    Full Text Available This paper presents a new tool for performing the integrated design and analysis of a sail. The features of the system are the geometrical definition of a sail shape, using the Bezier surface method, the creation of a finite element model for the non-linear structural analysis and a fluid-dynamic model for the aerodynamic analysis. The system has been developed using MATLAB(r. Recent sail design efforts have been focused on solving the aeroelastic behavior of the sail. The pressure distribution on a sail changes continuously, by virtue of cloth stretch and flexing. The sail shape determines the pressure distribution and, at the same time, the pressure distribution on the sail stretches and flexes the sail material determining its shape. This characteristic non-linear behavior requires iterative solution strategies to obtain the equilibrium configuration and evaluate the forces involved. The aeroelastic problem is tackled by combining structural with aerodynamic analysis. Firstly, pressure loads for a known sail-shape are computed (aerodynamic analysis. Secondly, the sail-shape is analyzed for the obtained external loads (structural analysis. The final solution is obtained by using an iterative analysis process, which involves both aerodynamic and the structural analysis. When the solution converges, it is possible to make design modifications.

  5. 5th International Robotic Sailing Conference

    CERN Document Server

    Finnis, James

    2013-01-01

    Robotic sailing offers the potential of wind propelled vehicles which are sufficiently autonomous to remain at sea for months at a time. These could replace or augment existing oceanographic sampling systems, be used in border surveillance and security or offer a means of carbon neutral transportation. To achieve this represents a complex, multi-disciplinary challenge to boat designers and naval architects, systems/electrical engineers and computer scientists.  Since 2004 a series of competitions in the form of the Sailbot, World Robotic Sailing Championship and Microtransat competitions have sparked an explosion in the number of groups working on autonomous sailing robots. Despite this interest the longest distance sailed autonomously remains only a few hundred miles. Many of the challenges in building truly autonomous sailing robots still remain unsolved. These proceedings present the cutting edge of work in a variety of fields related to robotic sailing. They will be presented during the 5th International...

  6. 9th International Robotic Sailing Conference

    CERN Document Server

    Cruz, Nuno

    2017-01-01

    This book contains selected papers that address a variety of topics related to the design, development and operation of unmanned and fully autonomous sailing boats. These papers were presented in the 9th International Robotic Sailing Conference, in association with the 9th World Robotic Sailing Championship that took place in Viana do Castelo, Portugal from the 5th to 10th of September 2016. The book is divided in three parts, each focusing on key aspects of robotic sailing. The first part addresses the design, construction and validation of autonomous sailboat platforms, including their rigs, appendages and control mechanisms. The second part is devoted to the development of sensors and algorithms to enhance the performance of robotic sailing boats, in terms of their speed, course control and manoeuvring ability. Finally, the papers in the last part are dedicated to the improvement of behaviours required for the accomplishment of complex autonomous missions. Robotic sailing is a relatively new multidisciplin...

  7. 7th International Robotic Sailing Conference

    CERN Document Server

    Tynan, Dermot

    2015-01-01

    An autonomous sailboat robot is a boat that only uses the wind on its sail as the propelling force, without remote control or human assistance to achieve its mission. Robotic sailing offers the potential of long range and long term autonomous wind propelled, solar or wave-powered carbon neutral devices. Robotic sailing devices could contribute to monitoring of environmental, ecological, meteorological, hydrographic and oceanographic data. These devices can also be used in traffic monitoring, border surveillance, security, assistance and rescue. The dependency on changing winds and sea conditions presents a considerable challenge for short and long term route and stability planning, collision avoidance and boat control. Building a robust and seaworthy sailing robot presents a truly complex and multi-disciplinary challenge for boat designers, naval architects, systems/electrical engineers and computer scientists. Over the last decade, several events such as Sailbot, World Robotic Sailing Championship and the In...

  8. 8th International Robotic Sailing Conference

    CERN Document Server

    Haug, Florian

    2016-01-01

    This book presents the cutting edge developments within a broad field related to robotic sailing. The contributions were presented during the 8th International Robotic Sailing Conference, which has taken place as a part of the 2015 World Robotic Sailing Championships in Mariehamn, Åland (Finland), August 31st – September 4th 2015. Since more than a decade, a series of competitions such as the World Robotic Sailing Championship have stimulated a variety of groups to work on research and development around autonomous sailing robots, which involves boat designers, naval architects, electrical engineers and computer scientists. While many of the challenges in building a truly autonomous sailboat are still unsolved, the books presents the state of the art of research and development within platform optimization, route and stability planning, collision avoidance, power management and boat control.

  9. FeatherSail--Design, Development and Future Impact

    Science.gov (United States)

    Alhorn, Dean C.; Scheierl, John M.

    2010-01-01

    This CD contains the slide presentation and a brief video of the solar sail concept. Solar Sailing is a method of space flight propulsion, which utilizes the light photons to propel spacecrafts through the vacuum of space. The goal of the FeatherSail project is to create a sail vehicle with the ability to provide steering from the sails and increase the areal density.

  10. FeatherSail - Design, Development and Future Impact

    Science.gov (United States)

    Alhorn, Dean C.; Scheierl, J. M.

    2010-01-01

    To the present day, the idea of using solar sails for space propulsion is still just a concept, but one that provides a great potential for future space exploration missions. Several notable solar propulsion missions and experiments have been performed and more are still in the development stage. Solar Sailing is a method of space flight propulsion, which utilizes the light photons to propel spacecrafts through the vacuum of space. This concept will be tested in the near future with the launch of the NanoSail-D satellite. NanoSail-D is a nano-class satellite, design concept, dubbed FeatherSail, has been developed. The goal of the FeatherSail project is to create a sail vehicle with the ability to provide steering from the sails and increase the areal density. The FeatherSail design will utilize the NanoSail-D based extendable boom technology with only one sail on each set of booms. This design also allows each of the four sails to feather as much as ninety degrees. The FeatherSail concept uses deployable solar arrays to generate the power necessary for deep space missions. In addition, recent developments in low power, low temperature Silicon-Germanium electronics provide the capability for long duration deep space missions. It is envisioned that the FeatherSail conceptual design will provide the impetus for future sail vehicles, which may someday visit distant places that mankind has only observed.

  11. Physical requirements in Olympic sailing

    DEFF Research Database (Denmark)

    Bojsen-Møller, J; Larsson, B; Aagaard, Per

    2015-01-01

    ) in a complete national Olympic delegation. The yachts have different requirements with respect to handling, and moreover, each sailor plays a specific role when sailing. Therefore physical demands remain heterogeneous for Olympic sailors. Previous studies have mainly examined sailors where 'hiking' (the task....... Another group of studies has investigated boardsailing and provided evidence to show that windsurfing requires very high aerobic and anaerobic capacity. Although data exist on other types of sailors, the information is limited, and moreover the profile of the Olympic events has changed markedly over...... of leaning over the side of the yacht to increase righting moment) is the primary requirement. Other than the ability to sustain prolonged quasi-isometric contractions, hiking seems to require significant maximal muscle strength especially in knee extensors, hip flexors and abdominal and lower back muscles...

  12. AERODYNAMICS OF WING TIP SAILS

    Directory of Open Access Journals (Sweden)

    MUSHTAK AL-ATABI

    2006-06-01

    Full Text Available Observers have always been fascinated by soaring birds. An interesting feature of these birds is the existence of few feathers extending from the tip of the wing. In this paper, small lifting surfaces were fitted to the tip of a NACA0012 wing in a fashion similar to that of wing tip feathers. Experimental measurements of induced drag, longitudinal static stability and trailing vortex structure were obtained.The tests showed that adding wing tip surfaces (sails decreased the induced drag factor and increased the longitudinal static stability. Results identified two discrete appositely rotated tip vortices and showed the ability of wing tip surfaces to break them down and to diffuse them.

  13. Unsteady Sail Dynamics in Olympic Class Sailboats

    Science.gov (United States)

    Williamson, Charles; Schutt, Riley

    2016-11-01

    Unsteady sailing techniques have evolved in competitive sailboat fleets, in cases where the relative weight of the sailor is sufficient to impart unsteady motions to the boat and sails. We will discuss three types of motion that are used by athletes to propel their boats on an Olympic race course faster than using the wind alone. In all of our cases, body weight movements induce unsteady sail motion, increasing driving force and speed through the water. In this research, we explore the dynamics of an Olympic class Laser sailboat equipped with a GPS, IMU, wind sensor, and a 6-GoPro camera array. We shall briefly discuss "sail flicking", whereby the helmsman periodically rolls the sail into the apparent wind, at an angle which is distinct from classical heave (in our case, the oscillations are not normal to the apparent flow). We also demonstrate "roll tacking", where there are considerable advantages to rolling the boat during such a maneuver, especially in light wind. In both of the above examples from on-the-water studies, corresponding experiments using a towing tank exhibit increases in the driving force, associated with the formation of strong vortex pairs into the flow. Finally, we focus on a technique known as "S-curving" in the case where the boat sails downwind. In contrast to the previous cases, it is drag force rather than lift force that the sailor is trying to maximise as the boat follows a zig-zag trajectory. The augmented apparent wind strength due to the oscillatory sail motion, and the growth of strong synchronised low-pressure wake vortices on the low-pressure side of the sail, contribute to the increase in driving force, and velocity-made-good downwind.

  14. Selection and Manufacturing of Membrane Materials for Solar Sails

    Science.gov (United States)

    Bryant, Robert G.; Seaman, Shane T.; Wilkie, W. Keats; Miyaucchi, Masahiko; Working, Dennis C.

    2013-01-01

    Commercial metallized polyimide or polyester films and hand-assembly techniques are acceptable for small solar sail technology demonstrations, although scaling this approach to large sail areas is impractical. Opportunities now exist to use new polymeric materials specifically designed for solar sailing applications, and take advantage of integrated sail manufacturing to enable large-scale solar sail construction. This approach has, in part, been demonstrated on the JAXA IKAROS solar sail demonstrator, and NASA Langley Research Center is now developing capabilities to produce ultrathin membranes for solar sails by integrating resin synthesis with film forming and sail manufacturing processes. This paper will discuss the selection and development of polymer material systems for space, and these new processes for producing ultrathin high-performance solar sail membrane films.

  15. Electric solar wind sail mass budget model

    Directory of Open Access Journals (Sweden)

    P. Janhunen

    2013-02-01

    Full Text Available The electric solar wind sail (E-sail is a new type of propellantless propulsion system for Solar System transportation, which uses the natural solar wind to produce spacecraft propulsion. The E-sail consists of thin centrifugally stretched tethers that are kept charged by an onboard electron gun and, as such, experience Coulomb drag through the high-speed solar wind plasma stream. This paper discusses a mass breakdown and a performance model for an E-sail spacecraft that hosts a mission-specific payload of prescribed mass. In particular, the model is able to estimate the total spacecraft mass and its propulsive acceleration as a function of various design parameters such as the number of tethers and their length. A number of subsystem masses are calculated assuming existing or near-term E-sail technology. In light of the obtained performance estimates, an E-sail represents a promising propulsion system for a variety of transportation needs in the Solar System.

  16. Viking-Age Sails: Form and Proportion

    Science.gov (United States)

    Bischoff, Vibeke

    2017-04-01

    Archaeological ship-finds have shed much light on the design and construction of vessels from the Viking Age. However, the exact proportions of their sails remain unknown due to the lack of fully preserved sails, or other definite indicators of their proportions. Key Viking-Age ship-finds from Scandinavia—the Oseberg Ship, the Gokstad Ship and Skuldelev 3—have all revealed traces of rigging. In all three finds, the keelson—with the mast position—is preserved, together with fastenings for the sheets and the tack, indicating the breadth of the sail. The sail area can then be estimated based on practical experience of how large a sail the specific ship can carry, in conjunction with hull form and displacement. This article presents reconstructions of the form and dimensions of rigging and sail based on the archaeological finds, evidence from iconographic and written sources, and ethnographic parallels with traditional Nordic boats. When these sources are analysed, not only do the similarities become apparent, but so too does the relative disparity between the archaeological record and the other sources. Preferential selection in terms of which source is given the greatest merit is therefore required, as it is not possible to afford them all equal value.

  17. A Deweyian Framework for Youth Development in Experiential Education: Perspectives from Sail Training and Sailing Instruction

    Science.gov (United States)

    Wojcikiewicz, Steven K.; Mural, Zachary B.

    2010-01-01

    In this piece, we put forth a Deweyian framework for youth development activities in outdoor and adventure education programs, and we show how such a framework may be exemplified by activities in sail training and sailing instruction. The paper begins with a discussion of the theoretical features of Deweyian educational experiences and makes…

  18. The life cycle of Ice Sails

    Science.gov (United States)

    Evatt, Geoff; Mayer, Christoph; Abrahams, I. d.; Nicholson, Lindsey; Mallinson, Amy; Heil, Matthias

    2016-04-01

    The Karakoram mountain region is host to many debris-covered glaciers. A notable feature from a sub-set of mainly larger glaciers with flat tongues, is the phenomenon of `Ice Sails'. These Ice Sails are clean ice structures that protrude out of the surrounding debris-covered glacier. They can be up to 20 meters in height, with widths of up to 90 meters, and generally have flat-sided faces. They appear to grow out of areas of glacier with thin debris coverage, then persist for decades as the glacier flows downstream, before declining back into the glacier several kilometres later. Here we aim to define and categorise these ice structures, and then explain their growth, persistence and decay. In particular, we show that their growth is due to the melt rate of inclined clean-ice being smaller than that of the surrounding flat thinly-debris-covered ice, allowing these structures to appear to grow out of the debris layer. But as the glacier flows downstream, this debris thickness slowly thickens, causing the corresponding melt-rate of the underlying ice to decline. Eventually, the melt-rate of the debris-covered ice becomes lower than that of the Ice Sail's melt-rate, at which point the decaying process of the Ice Sail commences. We develop a model to quantify this process, and in so doing, draw out the key parameters that govern the existence of Ice Sails.

  19. Stability of a Light Sail Riding on a Laser Beam

    OpenAIRE

    Manchester, Zachary; Loeb, Abraham

    2016-01-01

    The stability of a light sail riding on a laser beam is analyzed both analytically and numerically. Conical sails on Gaussian beams, which have been studied in the past, are shown to be unstable without active control or additional mechanical modifications. A new architecture for a passively stable sail and beam configuration is proposed. The novel spherical shell design for the sail is capable of "beam riding" without the need for active feedback control. Full three-dimensional ray-tracing s...

  20. Electric sailing. Elektrisch varen is dichterbij dan elektrisch rijden

    Energy Technology Data Exchange (ETDEWEB)

    Voorter, P.H.C. (ed.)

    Based on the lectures held at a symposium of the Foundation Electric Sailing in Giethoorn, Netherlands, April 15, 1994, and the report 'Energy and environmental aspects of electric sailing' of the Netherlands Energy Research Foundation in Petten, Netherlands, attention is paid to the potential of electric sailing in the Netherlands. Also the environmental effects, the energy efficiency, and the costs of electric sailing are briefly discussed. 3 figs., 3 ills., 2 refs.

  1. Deployment Testing of the De-Orbit Sail Flight Hardware

    OpenAIRE

    Hillebrandt, Martin; Meyer, Sebastian; Zander, Martin; Hühne, Christian

    2015-01-01

    The paper describes the results of the deployment testing of the De-Orbit Sail flight hardware, a drag sail for de-orbiting applications, performed by DLR. It addresses in particular the deployment tests of the fullscale sail subsystem and deployment force tests performed on the boom deployment module. For the fullscale sail testing a gravity compensation device is used which is described in detail. It allows observations of the in-plane interaction of the booms with the sail membrane and the...

  2. Parametric Studies of Square Solar Sails Using Finite Element Analysis

    Science.gov (United States)

    Sleight, David W.; Muheim, Danniella M.

    2004-01-01

    Parametric studies are performed on two generic square solar sail designs to identify parameters of interest. The studies are performed on systems-level models of full-scale solar sails, and include geometric nonlinearity and inertia relief, and use a Newton-Raphson scheme to apply sail pre-tensioning and solar pressure. Computational strategies and difficulties encountered during the analyses are also addressed. The purpose of this paper is not to compare the benefits of one sail design over the other. Instead, the results of the parametric studies may be used to identify general response trends, and areas of potential nonlinear structural interactions for future studies. The effects of sail size, sail membrane pre-stress, sail membrane thickness, and boom stiffness on the sail membrane and boom deformations, boom loads, and vibration frequencies are studied. Over the range of parameters studied, the maximum sail deflection and boom deformations are a nonlinear function of the sail properties. In general, the vibration frequencies and modes are closely spaced. For some vibration mode shapes, local deformation patterns that dominate the response are identified. These localized patterns are attributed to the presence of negative stresses in the sail membrane that are artifacts of the assumption of ignoring the effects of wrinkling in the modeling process, and are not believed to be physically meaningful. Over the range of parameters studied, several regions of potential nonlinear modal interaction are identified.

  3. The International Sailing Canoe: A Technical Review

    Science.gov (United States)

    1994-10-01

    the rule makers outlawed its use before it could be tested (111, p. 21). To maintain the same mainsail weight as the single-luff sails, a lightweight...Sailboats; Fran DeFaymoreau, Ad- vanced Marine Composites; Ben Fuller. Rockport Appren. ticeshop; Bruce Nelson, Nelson-Marek Yacht Design; Del Olsen

  4. Logarithmic spiral trajectories generated by Solar sails

    Science.gov (United States)

    Bassetto, Marco; Niccolai, Lorenzo; Quarta, Alessandro A.; Mengali, Giovanni

    2018-02-01

    Analytic solutions to continuous thrust-propelled trajectories are available in a few cases only. An interesting case is offered by the logarithmic spiral, that is, a trajectory characterized by a constant flight path angle and a fixed thrust vector direction in an orbital reference frame. The logarithmic spiral is important from a practical point of view, because it may be passively maintained by a Solar sail-based spacecraft. The aim of this paper is to provide a systematic study concerning the possibility of inserting a Solar sail-based spacecraft into a heliocentric logarithmic spiral trajectory without using any impulsive maneuver. The required conditions to be met by the sail in terms of attitude angle, propulsive performance, parking orbit characteristics, and initial position are thoroughly investigated. The closed-form variations of the osculating orbital parameters are analyzed, and the obtained analytical results are used for investigating the phasing maneuver of a Solar sail along an elliptic heliocentric orbit. In this mission scenario, the phasing orbit is composed of two symmetric logarithmic spiral trajectories connected with a coasting arc.

  5. Model and trajectory optimization for an ideal laser-enhanced solar sail

    NARCIS (Netherlands)

    Carzana (student TUDelft), Livio; Dachwald, Bernd; Noomen, R.

    2017-01-01

    A laser-enhanced solar sail is a solar sail that is not solely propelled by solar radiation but additionally by a laser beam that illuminates the sail. This way, the propulsive acceleration of the sail results from the combined action of the solar and the laser radiation pressure onto the sail. The

  6. Injury and illness surveillance at the International Sailing Federation Sailing World Championships 2014.

    Science.gov (United States)

    Tan, Benedict; Leong, Darren; Vaz Pardal, Carmen; Lin, Cindy Y; Kam, Jia Wen

    2016-06-01

    The Sailing World Championships 2014 was contested by 1167 sailors in all 10 Olympic classes. Our objective was to characterise sailing-related injuries and illnesses in sailors participating in this regatta. We conducted 2 surveys: (1) prior to the World Championships, sailors answered a 12-month recall questionnaire on sailing-related injuries and illnesses and (2) during the Championships, injuries and illnesses were documented. There were 760 respondents (65% of all participants) for the 12-month recall questionnaire (58% male, 42% female), of whom 244 participants reported 299 injuries (0.59 injuries per 1000 h of sailing). Injuries were most prevalent in the 49erFX (64%), RS:X Women (39%), 49er (37%) and Nacra 17 (36%). Lower back (29% of sailors), knee (13%), shoulder (12%) and ankle (10%) injuries were most prevalent; most (58% of all injuries) were overuse injuries; and 56% of sailors lost sailing time. Most illnesses (40%) were infections, primarily of the respiratory system (43%). During the Championships, there were 67 injuries (4 per 1000 days of sailing). The 49er (24% of all injuries), 470 Men and Women (24%), and 49erFX (19%) had the highest incidence. Injuries to the hand/fingers (22% of all injuries), back (18%), and foot (12%) were most common, as were contusions (37% of all injuries), cuts/lacerations (24%), and sprains (9%). Of the 29 illnesses (2 per 1000 days of sailing), 9 (31%) were gastrointestinal and 6 (21%) respiratory, while 2 (7%) were gout attacks. The Olympic classes introduced since 2000 (49erFX, 49er, Nacra 17) have resulted in a rise in injuries. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  7. The dynamics and control of the CubeSail mission: A solar sailing demonstration

    Science.gov (United States)

    Pukniel, Andrew; Coverstone, Victoria; Burton, Rodney; Carroll, David

    2011-12-01

    The CubeSail mission is a low-cost demonstration of the UltraSail solar sailing concept ( Burton et al., 2005; Botter et al., 2006; Hargens-Rysanek, 2006; Pukniel, 2009), using two near-identical CubeSat satellites to deploy a 260 m-long, 20 m 2 reflecting film. The two satellites are launched as a unit, detumbled, and separated, with the film unwinding symmetrically from motorized reels. The conformity to the CubeSat specification allows for reduction in launch costs as a secondary payload and utilization of the University of Illinois-developed spacecraft bus. The CubeSail demonstration is the first in a series of increasingly-complex missions aimed at validating several spacecraft subsystems, including attitude determination and control, the separation release unit, reel-based film deployment, as well as the dynamical behavior of the sail and on-orbit solar propulsion. The presented work describes dynamical behavior and control methods used during three main phases of the mission. The three phases include initial detumbling and stabilization using magnetic torque actuators, gravity-gradient-based deployment of the film, and steady-state film deformations in low Earth orbit in the presence of external forces of solar radiation pressure, aerodynamic drag, and gravity-gradient.

  8. Independent sailing with high tetraplegia using sip and puff controls: integration into a community sailing center.

    Science.gov (United States)

    Rojhani, Solomon; Stiens, Steven A; Recio, Albert C

    2017-07-01

    We are continually rediscovering how adapted recreational activity complements the rehabilitation process, enriches patients' lives and positively impacts outcome measures. Although sports for people with spinal cord injuries (SCI) has achieved spectacular visibility, participation by high cervical injuries is often restricted due to poor accessibility, safety concerns, lack of adaptability, and high costs of technology. We endeavor to demonstrate the mechanisms, adaptability, accessibility, and benefits the sport of sailing creates in the rehabilitative process. Our sailor is a 27-year-old man with a history of traumatic SCI resulting in C4 complete tetraplegia. The participant completed an adapted introductory sailing course, and instruction on the sip-and-puff sail and tiller control mechanism. With practice, he navigated an on-water course in moderate winds of 5 to 15 knots. Despite trends toward shorter rehabilitation stays, aggressive transdisciplinary collaboration with recreation therapy can provide community and natural environment experiences while inpatient and continuing post discharge. Such peak physical and psychological experiences provide a positive perspective for the future that can be shared on the inpatient unit, with families and support systems like sailing clubs in the community. Rehabilitation theory directs a team process to achieve patient self-awareness and initiate self-actualization in spite of disablement. Utilization of local community sailing centers that have provided accessible assisted options provides person-centered self-realization of goals as assisted by family and natural supports. Such successful patients become native guides for others seeking the same experience.

  9. Solar sail propulsion: enabling new capabilities for heliophysics

    CERN Document Server

    Johnson, L; Alhorn, D; Heaton, A; Vansant, T; Campbell, B; Pappa, R; Keats, W; Liewer, P C; Alexander, D; Ayon, J; Wawrzyniak, G; Burton, R; Carroll, D; Matloff, G; Kezerashvili, R Ya

    2010-01-01

    Solar sails can play a critical role in enabling solar and heliophysics missions. Solar sail technology within NASA is currently at 80% of TRL-6, suitable for an in-flight technology demonstration. It is conceivable that an initial demonstration could carry scientific payloads that, depending on the type of mission, are commensurate with the goals of the three study panels of the 2010 Heliophysics Survey. Follow-on solar sail missions, leveraging advances in solar sail technology to support Heliophysics Survey goals, would then be feasible. This white paper reports on a sampling of missions enabled by solar sails, the current state of the technology, and what funding is required to advance the current state of technology such that solar sails can enable these missions.

  10. Hiking strap force decreases during sustained upwind sailing

    DEFF Research Database (Denmark)

    Buchardt, R; Bay, Jonathan; Bojsen-Møller, Jens

    2017-01-01

    The hypothesis, that sailing upwind in wind speeds above 12 knots causes fatigue, which manifests as a reduction in exerted hiking strap force and/or maximal isometric voluntary contraction force (MVC) of the knee extensors, was evaluated. Additionally, it was investigated if a relationship exists...... between maximal exerted hiking force (hMVC) and sailing performance. In part 1 of the study, 12 national level athletes sailed upwind for 2 × 10 min while hiking strap forces were continuously acquired. Before, in between and after sailing periods, the MVC of the knee extensors was measured. In part 2...... causes sailing-specific fatigue as evidenced by a marked reduction in exerted hiking strap force. However, MVC of the knee extensors was not compromised ∼45 s after hiking was terminated. Additionally, sailing performance is related to maximal hiking force....

  11. Mars Sample Return Using Solar Sail Propulsion

    Science.gov (United States)

    Johnson, Les; Macdonald, Malcolm; Mcinnes, Colin; Percy, Tom

    2012-01-01

    Many Mars Sample Return (MSR) architecture studies have been conducted over the years. A key element of them is the Earth Return Stage (ERS) whose objective is to obtain the sample from the Mars Ascent Vehicle (MAV) and return it safely to the surface of the Earth. ERS designs predominantly use chemical propulsion [1], incurring a significant launch mass penalty due to the low specific impulse of such systems coupled with the launch mass sensitivity to returned mass. It is proposed to use solar sail propulsion for the ERS, providing a high (effective) specific impulse propulsion system in the final stage of the multi-stage system. By doing so to the launch mass of the orbiter mission can be significantly reduced and hence potentially decreasing mission cost. Further, solar sailing offers a unique set of non-Keplerian low thrust trajectories that may enable modifications to the current approach to designing the Earth Entry Vehicle by potentially reducing the Earth arrival velocity. This modification will further decrease the mass of the orbiter system. Solar sail propulsion uses sunlight to propel vehicles through space by reflecting solar photons from a large, mirror-like surface made of a lightweight, reflective material. The continuous photonic pressure provides propellantless thrust to conduct orbital maneuvering and plane changes more efficiently than conventional chemical propulsion. Because the Sun supplies the necessary propulsive energy, solar sails require no onboard propellant, thus reducing system mass. This technology is currently at TRL 7/8 as demonstrated by the 2010 flight of the Japanese Aerospace Exploration Agency, JAXA, IKAROS mission. [2

  12. Simulated Space Environment Effects on a Candidate Solar Sail Material

    Science.gov (United States)

    Kang, Jin Ho; Bryant, Robert G.; Wilkie, W. Keats; Wadsworth, Heather M.; Craven, Paul D.; Nehls, Mary K.; Vaughn, Jason A.

    2017-01-01

    For long duration missions of solar sails, the sail material needs to survive harsh space environments and the degradation of the sail material controls operational lifetime. Therefore, understanding the effects of the space environment on the sail membrane is essential for mission success. In this study, we investigated the effect of simulated space environment effects of ionizing radiation, thermal aging and simulated potential damage on mechanical, thermal and optical properties of a commercial off the shelf (COTS) polyester solar sail membrane to assess the degradation mechanisms on a feasible solar sail. The solar sail membrane was exposed to high energy electrons (about 70 keV and 10 nA/cm2), and the physical properties were characterized. After about 8.3 Grad dose, the tensile modulus, tensile strength and failure strain of the sail membrane decreased by about 20 95%. The aluminum reflective layer was damaged and partially delaminated but it did not show any significant change in solar absorbance or thermal emittance. The effect on mechanical properties of a pre-cracked sample, simulating potential impact damage of the sail membrane, as well as thermal aging effects on metallized PEN (polyethylene naphthalate) film will be discussed.

  13. Characterization of candidate solar sail materials subjected to electron radiation

    Science.gov (United States)

    Edwards, David L.; Hubbs, Whitney S.; Gray, Perry A.; Wertz, George E.; Hoppe, David T.; Nehls, Mary K.; Semmel, Charles L.; Albarado, Tesia L.; Hollerman, William A.

    2003-09-01

    Solar sailing is a unique form of propulsion in which a spacecraft gains momentum from incident photons. Solar sails are not limited by reaction mass and provide continual acceleration, reduced only by the lifetime of the light-weight film in the space environment and the distance to the Sun. Once considered difficult or impossible, solar sailing has left the realm of science fiction for the realm of possibility. Any spacecraft using this method would need to deploy a thin sail that could be as large as many kilometers in extent. The availability of strong, ultra light-weight, and radiation-resistant materials will determine the future of solar sailing. The National Aeronautics and Space Administration's (NASA's) Marshall Space Flight Center (MSFC) is concentrating research into the use of ultra light-weight materials for spacecraft propulsion. MSFC's Space Environmental Effects Team is actively characterizing candidate solar sail materials to evaluate thermo-optical and mechanical properties after exposure to space environmental effects. This paper describes irradiation of candidate materials with energetic electrons in vacuum to determine the hardness of several candidate sail materials. [Hardness is defined as the amount of electron fluence (electrons/area) required to cause the sail material to fail.] This paper describes the testing procedure and preliminary results of this investigation. Comparisons to approximate the engineering functional lifetimes of candidate sail materials will be shown.

  14. Real-time sail and heading optimization for a surface sailing vessel by extremum seeking control

    DEFF Research Database (Denmark)

    Treichel, Kai; Jouffroy, Jerome

    2010-01-01

    In this paper we develop a simplified mathematical model representing the main elements of the behaviour of sailing vessels as a basis for simulation and controller design. For adaptive real-time optimization of the sail and heading angle we then apply extremum seeking control (which is a gradient...... based control law that drives the output of a linear or nonlinear system to its extremum) as an approach to maximize the longitudinal velocity. The basic idea behind extremum seeking and “how it works” is presented, as well as a simulation study on noise, convergence and stability issues....

  15. Consideration of puncture by micrometeors in the equations of motion of a solar-sail vehicle

    Science.gov (United States)

    Poliakhova, E. N.; Sharifkulova, G. A.; Shuvalov, V. V.

    The problem of the motion of a degrading solar sail is analyzed with allowance for the irreversible changes in the solar sail material (a metallized polymer film), including both erosion of the sail surface and puncture of the sail by micrometeors. The minimum mass and diameter of particles capable of puncturing the sail are estimated as a function of sail density, relative collision velocity, sail thickness, and its strength characteristic. The contribution of erosion due to collisions with micrometeor particles to the degradation of the sail is also estimated.

  16. Near Earth Asteroid Scout Solar Sail Thrust and Torque Model

    Science.gov (United States)

    Heaton, Andy; Ahmad, Naeem; Miller, Kyle

    2017-01-01

    The Near Earth Asteroid (NEA) Scout is a solar sail mission whose objective is to scout at least one Near Earth Asteroid to help prepare for human missions to Near Earth Asteroids. NEA Scout will launch as a secondary payload on the first SLS-Orion mission. NEA Scout will perform a small trim maneuver shortly after deploy from the spent SLS upper stage using a cold gas propulsion system, but from that point on will depend entirely on the solar sail for thrust. As such, it is important to accurately characterize the thrust of the sail in order to achieve mission success. Additionally, the solar sail creates a relatively large solar disturbance torque that must be mitigated. For early mission design studies a flat plate model of the solar sail with a fixed center of pressure was adequate, but as mission concepts and the sail design matured, greater fidelity was required. Here we discuss the progress to a three-dimensional sail model that includes the effects of tension and thermal deformation that has been derived from a large structural Finite Element Model (FEM) developed by the Langley Research Center. We have found that the deformed sail membrane affects torque relatively much more than thrust; a flat plate model could potentially model thrust well enough to close mission design studies, but a three-dimensional solar sail is essential to control system design. The three-dimensional solar sail model revealed that thermal deformations of unshielded booms would create unacceptably large solar disturbance torques. The original large FEM model was used in control and mission simulations, but was resulted in simulations with prohibitive run times. This led us to adapt the Generalized Sail Model (GSM) of Rios-Reyes. A design reference sail model has been baselined for NEA Scout and has been used to design the mission and control system for the sailcraft. Additionally, since NEA Scout uses reaction wheels for attitude pointing and control, the solar torque model is

  17. Near Earth Asteroid Solar Sail Engineering Development Unit Test Program

    Science.gov (United States)

    Lockett, Tiffany Russell; Few, Alexander; Wilson, Richard

    2017-01-01

    The Near Earth Asteroid (NEA) Scout project is a 30x20x10cm (6U) cubesat reconnaissance mission to investigate a near Earth asteroid utilizing an 86m2 solar sail as the primary propulsion system. This will be the largest solar sail NASA will launch to date. NEA Scout is a secondary payload currently manifested on the maiden voyage of the Space Launch System in 2018. In development of the solar sail subsystem, design challenges were identified and investigated for packaging within a 6U form factor and deployment in cis-lunar space. Analysis furthered understanding of thermal, stress, and dynamics of the stowed system and matured an integrated sail membrane model for deployed flight dynamics. This paper will address design, fabrication, and lessons learned from the NEA Scout solar sail subsystem engineering development unit. From optical properties of the sail material to folding and spooling the single 86m2 sail, the team has developed a robust deployment system for the solar sail. This paper will also address expected and received test results from ascent vent, random vibration, and deployment tests.

  18. Solar sail orbital motion about asteriods and binary asteroid systems

    NARCIS (Netherlands)

    Heiligers, M.J.; Scheeres, Daniel J.; Sims, J.A.; Leve, F.A.; McMahon, J.W.; Guo, Y.

    2017-01-01

    While SRP is often considered an undesirable effect, especially for missions to small bodies like asteroids and binary asteroid systems, this paper utilizes the SRP on a solar sail to generate artificial equilibrium points (AEPs) and displaced periodic orbits in these systems. While the solar sail

  19. Improving comfort while hiking in a sailing boat

    NARCIS (Netherlands)

    Jansen, A.J.; Van Abbema, A.; Howe, C.

    2012-01-01

    The paper presents the changes in perceived comfort while hiking in a sailing boat (in this case the Laser, a single-handed Olympic dinghy) due to a new design of hiking pads. The project used a ‘research by design method’. The aim was to improve sailing comfort which leads to lower fatigue and

  20. World Ships: The Solar-Photon Sail Option

    Science.gov (United States)

    Matloff, G. L.

    The World Ship, a spacecraft large enough to simulate a small-scale terrestrial internal environment, may be the best feasible option to transfer members of a technological civilization between neighboring stars. Because of the projected size of these spacecraft, journey durations of ~1,000 years seem likely. One of the propulsion options for World Ships is the hyper-thin, likely space-manufactured solar-photon sail, unfurled as close to the migrating civilization's home star as possible. Because the sail and associated structure can be wound around the habitat while not in use, it represents the only known ultimately feasible interstellar propulsion system that can be applied for en route galactic-cosmic ray shielding as well as acceleration/ deceleration. This paper reviews the three suggested sail configurations that can be applied to world ship propulsion: parachute, hollow-body and hoop sails. Possible existing and advanced sail and structure materials and the predicted effects on the sail of the near-Sun space environment are reviewed. Consideration of solar-photon-sail World Ships also affects SETI (the Search for Extraterrestrial Intelligence). Can we detect such craft in flight? When in a star's lifetime is migration using such craft likely? What classes of stars are good candidates for solar-sail World-Ship searches?

  1. Electron Radiation Effects on Candidate Solar Sail Material

    Science.gov (United States)

    Edwards, David L.; Hollerman, William A.; Hubbs, Whitney S.; Gray, Perry A.; Wertz, George E.; Hoppe, David T.; Nehls, Mary K.; Semmel, Charles L.

    2003-01-01

    Solar sailing is a unique form of propulsion where a spacecraft gains momentum from incident photons. Solar sails are not limited by reaction mass and provide continual acceleration, reduced only by the lifetime of the lightweight film in the space environment and the distance to the Sun. Once thought to be difficult or impossible, solar sailing has come out of science fiction and into the realm of possibility. Any spacecraft using this propulsion method would need to deploy a thin sail that could be as large as many kilometers in extent. The availability of strong, ultra lightweight, and radiation resistant materials will determine the future of solar sailing. The National Aeronautics and Space Administration's (NASA) Marshall Space Flight Center (MSFC) is concentrating research into the utilization of ultra lightweight materials for spacecraft propulsion. The Space Environmental Effects Team at MSFC is actively characterizing candidate solar sail material to evaluate the thermo-optical and mechanical properties after exposure to space environmental effects. This paper will describe the irradiation of candidate solar sail materials to energetic electrons, in vacuum, to determine the hardness of several candidate sail materials.

  2. Modeling and nonlinear heading control for sailing yachts

    DEFF Research Database (Denmark)

    Xiao, Lin; Jouffroy, Jerome

    2011-01-01

    This paper presents a study on the development and testing of a model-based heading controller for a sailing yacht. Using Fossen's compact notation for marine vehicles, we first describe a nonlinear 4-DOF dynamic model for a sailing yacht, including roll. Starting from this model, we then design...

  3. Modeling and nonlinear heading control for sailing yachts

    DEFF Research Database (Denmark)

    Xiao, Lin; Jouffroy, Jerome

    2014-01-01

    This paper presents a study on the development and testing of a model-based heading controller for a sailing yacht. Using Fossen’s compact notation for marine vehicles, we first describe a nonlinear four-degree-of-freedom (DOF) dynamic model for a sailing yacht, including roll. Our model also...

  4. On steering a sailing ship in a wearing maneuver

    DEFF Research Database (Denmark)

    Jouffroy, Jerome

    Compared to more conventional ships, little attention was given to nonlinear control design for ships sailing by the wind. Following our previous work, this paper addresses the issue of trajectory and reference input generation for a model that imitates the general behavior of sailing vessels...

  5. Displaced Electric Sail Orbits Design and Transition Trajectory Optimization

    Directory of Open Access Journals (Sweden)

    Naiming Qi

    2014-01-01

    Full Text Available Displaced orbits for spacecraft propelled by electric sails are investigated as an alternative to the use of solar sails. The orbital dynamics of electric sails based spacecraft are studied within a spherical coordinate system, which permits finding the solutions of displaced electric sail orbits and optimize transfer trajectory. Transfer trajectories from Earth's orbit to displaced orbit are also studied in an optimal framework, by using genetic algorithm and Gauss pseudospectral method. The initial guesses for the state and control histories used in the Gauss pseudospectral method are interpolated from the best solution of a genetic algorithm. Numerical simulations show that the electric sail is able to perform the transfer from Earth’s orbit to displaced orbit in acceptable time, and the hybrid optimization method has the capability to search the feasible and optimal solution without any initial value guess.

  6. ‘Physics on board’ sets sail!

    CERN Multimedia

    2009-01-01

    In 2005, Italy’s National Institute for Nuclear Physics (INFN) introduced a fun new educational initiative called ‘Physics on board’. CERN is now also on board, coordinating the project’s extension to European level and the participation of scientists from Portugal, Spain and France. School children at the Civitavecchia stopover (27/04/09), taking part in one of the ‘Physics on board ‘ activities, the ‘winch’, used to measure the multiplication factor of their own pulling force.‘Physics on board’ is a science outreach project with the aim of stimulating young people’s interest in physics by transforming a sailing yacht into a real-life travelling laboratory, specially designed with secondary-school children in mind. The ‘Adriatica’ is a vessel made famous by the Italian TV show Velisti per Caso, presented by Patrizio Roversi and Syusi Blady on Rai 3. As they sail up and down the Italian coastline, scientists f...

  7. Would you like to learn to sail?

    CERN Multimedia

    Yachting Club

    2011-01-01

    Registration for the 2011 lottery for YCC sailing courses has opened and it already looks as if similar numbers will try their luck as for past seasons. But don't be deterred, the Lottery is completely open and everyone has an equal chance. Please see also the list of courses and places offered. The deadline for registration is March 17th at midday. If you have any questions in advance, contact a Committee member or, better, come and ask the Club Committee representatives (Club permanence) on March 9th from 18:00 until 19:30 in the atrium of CERN building 40. Meanwhile your YCC committee has registered one new boat already, the first test of the current season has already been carried out (yes!) and some intrepid sailors go sailing regularly throughout the winter - it is true that it is a whole different lake at this time: not just temperature, but quality of light, Mont Blanc in a different style and fewer people out there... A few people are planning an early trip to warmer waters soon (like, the Balearics...

  8. Solar and Drag Sail Propulsion: From Theory to Mission Implementation

    Science.gov (United States)

    Johnson, Les; Alhorn, Dean; Boudreaux, Mark; Casas, Joe; Stetson, Doug; Young, Roy

    2014-01-01

    Solar and drag sail technology is entering the mainstream for space propulsion applications within NASA and around the world. Solar sails derive propulsion by reflecting sunlight from a large, mirror- like sail made of a lightweight, reflective material. The continuous sunlight pressure provides efficient primary propulsion, without the expenditure of propellant or any other consumable, allowing for very high V maneuvers and long-duration deep space exploration. Drag sails increase the aerodynamic drag on Low Earth Orbit (LEO) spacecraft, providing a lightweight and relatively inexpensive approach for end-of-life deorbit and reentry. Since NASA began investing in the technology in the late 1990's, significant progress has been made toward their demonstration and implementation in space. NASA's Marshall Space Flight Center (MSFC) managed the development and testing of two different 20-m solar sail systems and rigorously tested them under simulated space conditions in the Glenn Research Center's Space Power Facility at Plum Brook Station, Ohio. One of these systems, developed by L'Garde, Inc., is planned for flight in 2015. Called Sunjammer, the 38m sailcraft will unfurl in deep space and demonstrate solar sail propulsion and navigation as it flies to Earth-Sun L1. In the Flight Center (MSFC) managed the development and testing of two different 20-m solar sail systems and rigorously tested them under simulated space conditions in the Glenn Research Center's Space Power Facility at Plum Brook Station, Ohio. One of these systems, developed by L'Garde, Inc., is planned for flight in 2015. Called Sunjammer, the 38m sailcraft will unfurl in deep space and demonstrate solar sail propulsion and navigation as it flies to Earth-Sun L1. In the interim, NASA MSFC funded the NanoSail-D, a subscale drag sail system designed for small spacecraft applications. The NanoSail-D flew aboard the Fast Affordable Science and Technology SATellite (FASTSAT) in 2010, also developed by MSFC

  9. The leading-edge vortex of yacht sails

    Science.gov (United States)

    Arredondo-Galeana, Abel; Viola, Ignazio Maria

    2017-11-01

    We experimentally show, for the first time, that a stable Leading-Edge Vortex (LEV) can be formed on an asymmetric spinnaker, which is a high-lift sail used by yachts to sail downwind. We tested a 3D printed rigid sail in a water flume at a chord-based Reynolds number of ca. 104. We found that on the leeward side of the sail (the suction side), the flow separates at the leading edge reattaching further downstream and forming a stable LEV. The LEV grows in diameter from the root to the tip of the sail, where it merges with the tip vortex. We detected the LEV using the γ criterion, and we verified its stability over time. The lift contribution provided by the LEV was computed solving a complex potential model of each sail section. This analysis indicated that the LEV provides a substantial contribution to the total sail's lift. These findings suggest that the maximum lift of low-aspect-ratio wings with a sharp leading edge, such as spinnakers, can be enhanced by promoting a stable LEV. This work was funded by the Consejo Nacional de Ciencia y Tecnologia (CONACYT).

  10. An Update to the NASA Reference Solar Sail Thrust Model

    Science.gov (United States)

    Heaton, Andrew F.; Artusio-Glimpse, Alexandra B.

    2015-01-01

    An optical model of solar sail material originally derived at JPL in 1978 has since served as the de facto standard for NASA and other solar sail researchers. The optical model includes terms for specular and diffuse reflection, thermal emission, and non-Lambertian diffuse reflection. The standard coefficients for these terms are based on tests of 2.5 micrometer Kapton sail material coated with 100 nm of aluminum on the front side and chromium on the back side. The original derivation of these coefficients was documented in an internal JPL technical memorandum that is no longer available. Additionally more recent optical testing has taken place and different materials have been used or are under consideration by various researchers for solar sails. Here, where possible, we re-derive the optical coefficients from the 1978 model and update them to accommodate newer test results and sail material. The source of the commonly used value for the front side non-Lambertian coefficient is not clear, so we investigate that coefficient in detail. Although this research is primarily designed to support the upcoming NASA NEA Scout and Lunar Flashlight solar sail missions, the results are also of interest to the wider solar sail community.

  11. Attitude Dynamics and Control of Solar Sails

    Science.gov (United States)

    Sperber, Evan

    Solar sails are space vehicles that rely on solar radiation pressure in order to generate forces for thrust and attitude control torques. They exhibit characteristics such as large moments of inertia, fragility of various system components, and long mission durations that make attitude control a particularly difficult engineering problem. Thrust vector control (TVC) is a family of sailcraft attitude control techniques that is on a short list of strategies thought to be suitable for the primary attitude control of solar sails. Every sailcraft TVC device functions by manipulating the relative locations of the composite mass center (cm) of the sailcraft and the center of pressure (cp) of at least one of its reflectors. Relative displacement of these two points results in body torques that can be used to steer the sailcraft. This dissertation presents a strategy for the large-angle reorientation of a sailcraft using TVC. Two forms of TVC, namely the panel and ballast mass translation methods are well represented in the literature, while rigorous studies regarding a third form, gimballed mass rotation, are conspicuously absent. The gimballed mass method is physically realized by placing a ballast mass, commonly the sailcraft's scientific payload, at the tip of a gimballed boom that has its base fixed at some point on the sailcraft. A TVC algorithm will then strategically manipulate the payload boom's gimbal angles, thereby changing the projection of the sailcraft cm in the plane of the sail. This research demonstrates effective three-axis attitude control of a model sailcraft using numerical simulation of its nonlinear equations of motion. The particular TVC algorithm developed herein involves two phases---the first phase selects appropriate gimbal rates with the objective that the sailcraft be placed in the neighborhood of its target orientation. It was discovered, however that concomitantly minimizing attitude error as well as residual body rate was not possible using

  12. Stability criterion and its calculation for sail-assisted ship

    Directory of Open Access Journals (Sweden)

    Yihuai Hu

    2015-01-01

    Full Text Available Stability criterion and its calculation are the crucial issue in the application of sail-assisted ship. How- ever, there is at present no specific criterion and computational methods for the stability of sail-assisted ship. Based on the stability requirements for seagoing ships, the stability criterion of the sail-assisted ships is suggested in this paper. Furthermore, how to calculate the parameters and determine some specific coefficients for the ship stability calculation, as well as how to redraw stability curve are also discussed in this paper. Finally, to give an illustration, the proposed method is applied on a sail assisted-ship model with comments and recommendations for improvement.

  13. Stability criterion and its calculation for sail-assisted ship

    Directory of Open Access Journals (Sweden)

    Hu Yihuai

    2015-01-01

    Full Text Available Stability criterion and its calculation are the crucial issue in the application of sail-assisted ship. How- ever, there is at present no specific criterion and computational methods for the stability of sail-assisted ship. Based on the stability; requirements for seagoing ships, the stability criterion of the sail-assisted ships is suggested in this paper. Furthermore, how to calculate the parameters and determine some specific coefficients for the ship stability; calculation, as well as how to redraw stability! curve are also discussed in this paper. Finally, to give an illustration, the proposed method is applied on a sail assisted-ship model with comments and recommendations for improvement.

  14. Fuzzy attitude control of solar sail via linear matrix inequalities

    Science.gov (United States)

    Baculi, Joshua; Ayoubi, Mohammad A.

    2017-09-01

    This study presents a fuzzy tracking controller based on the Takagi-Sugeno (T-S) fuzzy model of the solar sail. First, the T-S fuzzy model is constructed by linearizing the existing nonlinear equations of motion of the solar sail. Then, the T-S fuzzy model is used to derive the state feedback controller gains for the Twin Parallel Distributed Compensation (TPDC) technique. The TPDC tracks and stabilizes the attitude of the solar sail to any desired state in the presence of parameter uncertainties and external disturbances while satisfying actuator constraints. The performance of the TPDC is compared to a PID controller that is tuned using the Ziegler-Nichols method. Numerical simulation shows the TPDC outperforms the PID controller when stabilizing the solar sail to a desired state.

  15. Asteroid rotation control via a tethered solar sail

    Science.gov (United States)

    Gao, Youtao; Wu, Jingyun

    2016-12-01

    The rotation of asteroids causes difficulties in the exploration of asteroids or prevention of asteroids impact on the Earth. We propose to use a solar sail to control, i.e., slow down or stop the rotational motion of an asteroid. First, the dynamic model of a tethered solar sail in the rotating gravitational field of an asteroid is presented. An optimal control method is employed to determine the control law of the tethered solar sail. The optimal control problem is converted into a nonlinear programming problem with the Gauss pseudospectral method. Simulation results show that this method can effectively slow down or even stop the rotation of an asteroid. A solar sail of 105 m2 can stop the rotation of the asteroid Apophis in 1000 days.

  16. Fast Solar Sailing for Solar System Exploration Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Practical spinning solar sail architectures will be needed to meet low areal densities and large areas required for the most challenging science and exploration...

  17. Solar sails a novel approach to interplanetary travel

    CERN Document Server

    Vulpetti, Giovanni; Matloff, Gregory L

    2015-01-01

    The reality of sunlight-based sailing in space began in May 2010,  and solar sail technology and science have continued to evolve rapidly through new space missions. Using the power of the Sun's light for regular travel propulsion will be the next major leap forward in our journey to other worlds. This book is the second edition of the fascinating explanation of solar sails, how they work and how they will be used in the exploration of space. Updated with 35% new material, this second edition includes three new chapters on missions operated by Japan and the US, as well as projects that are in progress. The remainder of the book describes the heritage of exploration in water-borne sailing ships and the evolution to space-vehicle propulsion; as well as nuclear, solar-electric, nuclear-electric and antimatter rocket devices. It also discusses various sail systems that may use either sunlight or solar wind, and the design, fabrication and steering challenges associated with solar sails. The first edition was me...

  18. Invited article: Electric solar wind sail: toward test missions.

    Science.gov (United States)

    Janhunen, P; Toivanen, P K; Polkko, J; Merikallio, S; Salminen, P; Haeggström, E; Seppänen, H; Kurppa, R; Ukkonen, J; Kiprich, S; Thornell, G; Kratz, H; Richter, L; Krömer, O; Rosta, R; Noorma, M; Envall, J; Lätt, S; Mengali, G; Quarta, A A; Koivisto, H; Tarvainen, O; Kalvas, T; Kauppinen, J; Nuottajärvi, A; Obraztsov, A

    2010-11-01

    The electric solar wind sail (E-sail) is a space propulsion concept that uses the natural solar wind dynamic pressure for producing spacecraft thrust. In its baseline form, the E-sail consists of a number of long, thin, conducting, and centrifugally stretched tethers, which are kept in a high positive potential by an onboard electron gun. The concept gains its efficiency from the fact that the effective sail area, i.e., the potential structure of the tethers, can be millions of times larger than the physical area of the thin tethers wires, which offsets the fact that the dynamic pressure of the solar wind is very weak. Indeed, according to the most recent published estimates, an E-sail of 1 N thrust and 100 kg mass could be built in the rather near future, providing a revolutionary level of propulsive performance (specific acceleration) for travel in the solar system. Here we give a review of the ongoing technical development work of the E-sail, covering tether construction, overall mechanical design alternatives, guidance and navigation strategies, and dynamical and orbital simulations.

  19. Fluid Distribution Analysis of Kite Sail for Application on Ship

    Directory of Open Access Journals (Sweden)

    . Amiadji

    2017-09-01

    Full Text Available The increasing number of operating ships resulted in high air pollution from the combustion of the ship's engine. Efforts to utilize alternative energy to reduce ship engine work have been done, one of them is using unlimited alternative energy that is wind where one of its application of is the application of new ships sail, kite sail as auxiliary system of ship propulsion . In this final project purposed to find out the value of aerodynamic force of kite sail and power it can generated , with a CFD method that uses 3 kite sail design forms, rectangular, triangular, and elliptical, with an area of 160 m2 this models are simulated at wind speed variations from 13.4 m / s up 15.82 m / s and angel of attack variation of 15.20, and 25. From the variation obtained the total aerodynamic force generated can reach 28.73 kN in rectangular shape, 30.79 kN of Elipsical shape, and 27.55 kN of triangular shape, on variant Angel Of attack 25. From the value of the aerodynamic force, each kite sail capable of generating power, on a rectangular kite sail of up to 263.02 kW, an elipsical 276.75 kW, and a triangular 252.63 kW.

  20. Combining Electric and Sail Propulsion for Interplanetary Sample Return

    Energy Technology Data Exchange (ETDEWEB)

    Noble, Robert

    2003-02-04

    Fast sample return from the outer Solar System would open an entirely new avenue for space science, but the vast distances make this a daunting task. The achievable transit velocity and the need for extra propellant on the return trip limit the feasibility of returning extraterrestrial samples to Earth. To keep the mission duration short enough to be of interest, sample return from objects farther out in the Solar System requires increasingly higher velocities. High specific impulse, electric propulsion reduces the propellant required for the outbound and return trips, but decelerating the spacecraft at the inner Solar System from high velocity still involves a long, inward spiral trajectory. The use of solar sails to rapidly decelerate incoming sample capsules and eliminate propellant is explored in this paper. The sail is essentially a ''solar parachute'' used for braking at the end of the interplanetary return flight, permitting a higher transit speed and truncating the deceleration spiral. In this application the sail is relatively small and manageable since only the sample capsule and its sail are decelerated. A comparison is made between using all-electric propulsion versus combining electric propulsive acceleration with sail deceleration for sample return from the distances of Saturn, Uranus, and Pluto. Solar-sail braking dramatically reduces the return flight time by one-third or more compared to using electric rocket deceleration. To elucidate the technology requirements, wide ranges for both the loaded sail density and electric propulsion specific mass are considered in this initial parametric study.

  1. Advanced Materials and Production Technology for Very Large Solar Sail Structures Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Solar sails are an attractive means for propulsion of future spacecraft. One potential device for deploying and supporting very large solar sails is the CoilAble...

  2. Plasma Deflection Test Setup for E-Sail Propulsion Concept

    Science.gov (United States)

    Andersen, Allen; Vaughn, Jason; Schneider, Todd; Wright, Ken

    2016-01-01

    The Electronic Sail or E-Sail is a novel propulsion concept based on momentum exchange between fast solar wind protons and the plasma sheath of long positively charged conductors comprising the E-Sail. The effective sail area increases with decreasing plasma density allowing an E-Sail craft to continue to accelerate at predicted ranges well beyond the capabilities of existing electronic or chemical propulsion spacecraft. While negatively charged conductors in plasmas have been extensively studied and flown, the interaction between plasma and a positively charged conductor is not well studied. We present a plasma deflection test method using a differential ion flux probe (DIFP). The DIFP measures the angle and energy of incident ions. The plasma sheath around a charged body can measured by comparing the angular distribution of ions with and without a positively charged test body. These test results will be used to evaluate numerical calculations of expected thrust per unit length of conductor in the solar wind plasma. This work was supported by a NASA Space Technology Research Fellowship.

  3. Solar kites: Small solar sails with no moving parts

    Science.gov (United States)

    Jack, C.; Welch, C. S.

    1997-01-01

    The classical concept of a solar sail is of a large area of silvered plastic deployed to reflect the Sun's rays thus propelling it. This arrangement would, however, be difficult to deploy and control, and impractical to launch from a low Earth orbit. This paper proposes an alternative concept to the classical solar sail — a small sail a few metres in diameter called a solar kite. Such a kite may be steered using very small torque forces and can therefore be controlled without the need for moving parts. Several such attitude control techniques are feasible: using windows of electrochromic material set in the sail; harnessing the effect of differential solar pressure on solar cells that are in or out of circuit; electrically heating wires to alter the geometry. Such solar kites may have a number of applications. Carrying a CCD camera on a chip and a medium gain antenna, a kite could be used for interplanetary mission and return dust samples to Earth. A kite attached to a satellite in LEO could be used for orbit control, reducing the need for thruster propellant. Long strings of kites, effectively large, one-dimensional solar sails, would be easier to deploy and control than two-dimensional ones and could be operated from much lower altitudes, ~ 500 km.

  4. Equilibria near asteroids for solar sails with reflection control devices

    Science.gov (United States)

    Gong, Shengping; Li, Junfeng

    2015-02-01

    Solar sails are well-suited for long-term, multiple-asteroid missions. The dynamics of solar sails near an asteroid have not yet been studied in detail. In this paper, out-of-plane artificial equilibria in a Sun-asteroid rotating frame and hovering points in a body-fixed rotating frame are studied (using a solar sail equipped with reflection control devices). First, the dynamics and the stability of out-of-plane artificial equilibria are studied as an elliptical restricted three body problem. Next, the body-fixed hovering problem is discussed as a two-body problem. Hovering flight is only possible for certain values of the latitude of the asteroid's orbit. In addition, the feasible range of latitudes is determined for each landmark on the asteroid's surface. The influence of the sail lightness number on the feasible range is also illustrated. Several special families of hovering points are discussed. These points include points above the equator and poles and points with an altitude equal to the radius of the synchronous orbit. In both of these types of problems, the solar sail (equipped with reflection control devices) can equilibrate over a large range of locations.

  5. System identification and the modeling of sailing yachts

    Science.gov (United States)

    Legursky, Katrina

    This research represents an exploration of sailing yacht dynamics with full-scale sailing motion data, physics-based models, and system identification techniques. The goal is to provide a method of obtaining and validating suitable physics-based dynamics models for use in control system design on autonomous sailing platforms, which have the capacity to serve as mobile, long range, high endurance autonomous ocean sensing platforms. The primary contributions of this study to the state-of-the-art are the formulation of a five degree-of-freedom (DOF) linear multi-input multi-output (MIMO) state space model of sailing yacht dynamics, the process for identification of this model from full-scale data, a description of the maneuvers performed during on-water tests, and an analysis method to validate estimated models. The techniques and results described herein can be directly applied to and tested on existing autonomous sailing platforms. A full-scale experiment on a 23ft monohull sailing yacht is developed to collect motion data for physics-based model identification. Measurements include 3 axes of accelerations, velocities, angular rates, and attitude angles in addition to apparent wind speed and direction. The sailing yacht herein is treated as a dynamic system with two control inputs, the rudder angle, deltaR, and the mainsail angle, delta B, which are also measured. Over 20 hours of full scale sailing motion data is collected, representing three sail configurations corresponding to a range of wind speeds: the Full Main and Genoa (abbrev. Genoa) for lower wind speeds, the Full Main and Jib (abbrev. Jib) for mid-range wind speeds, and the Reefed Main and Jib (abbrev. Reef) for the highest wind speeds. The data also covers true wind angles from upwind through a beam reach. A physics-based non-linear model to describe sailing yacht motion is outlined, including descriptions of methods to model the aerodynamics and hydrodynamics of a sailing yacht in surge, sway, roll, and

  6. In-Vacuum Photogrammetry of a 10-Meter Solar Sail

    Science.gov (United States)

    Meyer, Chris G.; Jones, Thomas W.; Lunsford, Charles B.; Pappa, Richard S.

    2005-01-01

    In July 2004, a 10-meter solar sail structure developed by L Garde, Inc. was tested in vacuum at the NASA Glenn 30-meter Plum Brook Space Power Facility in Sandusky, Ohio. The three main objections of the test were to demonstrate unattended deployment from a stowed configuration, to measure the deployed shape of the sail at both ambient and cryogenic room temperatures, and to measure the deployed structural dynamic characteristics (vibration modes). This paper summarizes the work conducted to fulfill the second test objective. The deployed shape was measured photogrammetrically in vacuum conditions with four 2-megapixel digital video cameras contained in custom made pressurized canisters. The canisters included high-intensity LED ring lights to illuminate a grid of retroreflective targets distributed on the solar sail. The test results closely matched pre-test photogrammetry numerical simulations and compare well with ABAQUS finite-element model predictions.

  7. Improving magnetosphere in situ observations using solar sails

    Science.gov (United States)

    Parsay, Khashayar; Schaub, Hanspeter; Schiff, Conrad; Williams, Trevor

    2018-01-01

    Past and current magnetosphere missions employ conventional spacecraft formations for in situ observations of the geomagnetic tail. Conventional spacecraft flying in inertially fixed Keplerian orbits are only aligned with the geomagnetic tail once per year, since the geomagnetic tail is always aligned with the Earth-Sun line, and therefore, rotates annually. Solar sails are able to artificially create sun-synchronous orbits such that the orbit apse line remains aligned with the geomagnetic tail line throughout the entire year. This continuous presence in the geomagnetic tail can significantly increase the science phase for magnetosphere missions. In this paper, the problem of solar sail formation design is explored using nonlinear programming to design optimal two-craft, triangle, and tetrahedron solar sail formations, in terms of formation quality and formation stability. The designed formations are directly compared to the formations used in NASA's Magnetospheric Multi-Scale mission.

  8. Displaced geostationary orbit design using hybrid sail propulsion

    OpenAIRE

    Heiligers, J.; Ceriotti, Matteo; McInnes, C.R.; J. D. Biggs

    2011-01-01

    Because of an increase in the number of geostationary spacecraft and the limits imposed by east–west spacing\\ud requirements, the geostationary orbit is becoming congested. To increase its capacity, this paper proposes to create\\ud new geostationary slots by displacing the geostationary orbit either out of or in the equatorial plane by means of\\ud hybrid solar sail and solar electric propulsion. To minimize propellant consumption, optimal steering laws for the\\ud solar sail and solar-electric...

  9. European sail tower SPS [Solar Power Satellite] concept

    Energy Technology Data Exchange (ETDEWEB)

    Seboldt, W.; Leipold, M.; Hanowski, N. [Institute of Space Sensor Technology and Planetary Exploration, Cologne (Germany). German Aerospace Center; Klimke, M. [HOPE Worldwide Deutschland, Berlin (Germany)

    2001-06-01

    Based on a DLR-study in 1998/99 on behalf of ESA/ESTEC called ''System Concepts, Architectures and Technologies for Space Exploration and Utilization (SE and U)'' a new design for an Earth-orbiting Solar Power Satellite (SPS) has been developed. The design is called ''European Sail Tower SPS'' and consists mainly of deplorable sail-like structures derived from the ongoing DLR/ESA solar sail technology development activity. Such an SPS satellite features an extremely light-weight and large tower-like orbital system and could supply Europe with significant amounts of electrical power generated by photovoltaic cells and subsequently transmitted to earth via microwaves. In order to build up the sail tower, 60 units - each consisting of a pair of square-shaped sails - are moved from LEO to GEO with electric propulsion and successively assembled in GEO robotically on a central strut. Each single sail has dimensions of 150 m x 150 m and is automatically deployed, using four diagonal lightweight carbon fiber (CFRP) booms which are initially rolled up on a central hub. The electric thrusters for the transport to GEO could also be used for orbit and attitude control of the assembled tower which has a total length of about 15 km and would be mainly gravity gradient stabilized. Employing thin film solar cell technology, each sail is used as a solar array and produces an electric power in orbit of about 3.7 MW{sub e}. A microwave antenna with a diameter of 1 km transmits the power to a 10 km rectenna on the ground. The total mass of this 450 MW SPS is about 2100 tons. First estimates indicate that the costs for one kWh delivered in this way could compete with present day energy costs, if launch costs would decrease by two orders of magnitude. Furthermore, mass production and large numbers of installed SPS systems must be assumed in order to lower significantly the production costs and to reduce the influence of the expensive technology

  10. Recent Progress in Heliogyro Solar Sail Structural Dynamics

    Science.gov (United States)

    Wilkie, William K.; Warren, Jerry E.; Horta, Lucas G.; Juang, Jer-Nan; Gibbs, Samuel C.; Dowell, E.; Guerrant, Daniel; Lawrence Dale

    2014-01-01

    Results from recent National Aeronautics and Space Administration (NASA) research on the structural dynamics and control characteristics of heliogyro solar sails are summarized. Specific areas under investigation include coupled nonlinear finite element analysis of heliogyro membrane blade with solar radiation pressure effects, system identification of spinning membrane structures, solarelastic stability analysis of heliogyro solar sails, including stability during blade deployment, and results from small-scale in vacuo dynamics experiments with spinning high-aspect ratio membranes. A low-cost, rideshare payload heliogyro technology demonstration mission concept, used as a mission context for these heliogyro structural dynamics and solarelasticity investigations, is also described.

  11. Hydrodynamics of sailing of the Portuguese man-of-war Physalia physalis.

    Science.gov (United States)

    Iosilevskii, G; Weihs, D

    2009-07-06

    Physalia physalis, commonly known as the Portuguese man-of-war (PMW), is a peculiar looking colony of specialized polyps. The most conspicuous members of this colony are the gas-filled sail-like float and the long tentacles, budding asymmetrically beneath the float. This study addresses the sailing of the PMW, and, in particular, the hydrodynamics of its trailing tentacles, the interaction between the tentacles and the float and the actual sailing performance. This paper attempts to provide answers for two of the many open questions concerning P. physalis: why does it need a sail? and how does it harness the sail?

  12. On path generation and feedforward control for a class of surface sailing vessels

    DEFF Research Database (Denmark)

    Xiao, Lin; Jouffroy, Jerome

    2010-01-01

    Sailing vessels with wind as their main means of propulsion possess a unique property that the paths they take depend on the wind direction, which, in the literature, has attracted less attention than normal vehicles propelled by propellers or thrusters. This paper considers the problem of motion...... planning and controllability for sailing vehicles representing the no-sailing zone effect in sailing. Following our previous work, we present an extended algorithm for automatic path generation with a prescribed initial heading for a simple model of sailing vehicles, together with a feedforward controller...

  13. Biobank Metaportal to Enhance Collaborative Research: sail.simbioms.org

    Directory of Open Access Journals (Sweden)

    Maria Krestyaninova

    2012-08-01

    Full Text Available In order to identify new ways to prevent, diagnose and treat diseases, biobanks systematically collect samples of human tissues and population-wide data on health and lifestyle. Efficient access to population biobank data and to biomaterial is crucial for development and marketing of new pharmaceutical products, especially in the area of personalised medicine. However, such access is hindered by legal and ethical constraints, and by the huge semantic diversity across different biobanks. To address these challenges, we have developed SAIL, a sophisticated metaportal for biobank data annotation across different collections and repositories, harmonised to allow cross-biobank searchability, while preserving the anonymity and privacy of the underlying data such that legal and ethical requirements are met. We describe the technological architecture and design of SAIL that allows us to meet these pressing challenges, and give an overview of the current functionality of the application. SAIL is available online at sail.simbioms.org, and it currently contains around 200 000 samples from 14 collections.

  14. Assessment of Inquiry Skills in the SAILS Project

    Science.gov (United States)

    Harrison, Chris

    2014-01-01

    Inquiry provides both the impetus and experience that helps students acquire problem solving and lifelong learning skills. Teachers on the Strategies for Assessment of Inquiry Learning in Science Project (SAILS) strengthened their inquiry pedagogy, through focusing on seeking assessment evidence for formative action. This paper reports on both the…

  15. On the feasibility of a negative polarity electric sail

    Directory of Open Access Journals (Sweden)

    P. Janhunen

    2009-04-01

    Full Text Available An electric solar wind sail is a recently introduced propellantless space propulsion method whose technical development has also started. In its original version, the electric sail consists of a set of long, thin, centrifugally stretched and conducting tethers which are charged positively and kept in a high positive potential of 20 kV by an onboard electron gun. The positively charged tethers deflect solar wind protons, thus tapping momentum from the solar wind stream and producing thrust. Here we consider a variant of the idea with negatively charged tethers. The negative polarity electric sail seems to be more complex to implement than the positive polarity variant since it needs an ion gun instead of an electron gun as well as a more complex tether structure to keep the electron field emission current in check with the tether surface. However, since this first study of the negative polarity electric sail does not reveal any fundamental issues, more detailed studies would be warranted.

  16. Sail Training as Education: More than Mere Adventure

    Science.gov (United States)

    McCulloch, K.; McLaughlin, P.; Allison, P.; Edwards, V.; Tett, L.

    2010-01-01

    This paper describes the process and findings of a multinational study of the characteristics of sail training for young people. The study used a structured qualitative method and involved "indigenous practitioner-researchers" who collected the majority of the data. Our findings show that participation provides an opportunity for…

  17. The epidemiology and aetiology of injuries in sailing.

    Science.gov (United States)

    Neville, Vernon; Folland, Jonathan P

    2009-01-01

    Sailors are at risk of injury and an understanding of the risks and causes of injury are important in helping to reduce their frequency and severity. Injuries are specific to the class of sailing. In elite Olympic-class sailing the incidence of injury is approximately 0.2 injuries/athlete/year, with the lumbar and thoracic spine and the knee most commonly injured. Poor hiking technique and inadequate leg strength are thought to predispose the knee to injury. Injuries in novice and recreational sailing are predominantly acute in nature with contusions and abrasions typically occurring as a result of collisions with the boom or other equipment during manoeuvres. The only report of injuries in Paralympic-class sailing found a high rate of approximately 100 injuries/1000 days of sailing, likely due to severe sailing conditions. The majority of injuries were chronic in nature, predominantly sprains and strains of the upper extremity. The risk of windsurfing injury ranged from 1.1 to 2.0 injuries/person/year, with the majority of injuries being acute, typically due to impact with equipment. Severe injuries are frequent, with competitive male windsurfers often admitted to hospital for treatment. Chronic lower back injuries are also common in windsurfers and may be related to prolonged lordosis (lumbar extension) of the spine while 'pumping' the sail. In professional big-boat sailing, America's Cup studies have reported an incidence of approximately 2.2 injuries/1000 hours of sailing, with one study reporting a higher incidence of injury during fitness training sessions (8.6 injuries/1000 hours of fitness training). The main cause of injury seems to be non-specific overuse, with joint and ligament sprains and tendinopathies being the most common. Grinders and bowmen are at greatest risk of injury, with the repetitive nature of 'grinding' a contributing factor. In round-the-world offshore racing, 1.5 injuries/person/round-the-world race (amateur), and 3.2 injuries

  18. SETI VIA LEAKAGE FROM LIGHT SAILS IN EXOPLANETARY SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    Guillochon, James; Loeb, Abraham, E-mail: jguillochon@cfa.harvard.edu, E-mail: aloeb@cfa.harvard.edu [Harvard-Smithsonian Center for Astrophysics, The Institute for Theory and Computation, 60 Garden Street, Cambridge, MA 02138 (United States)

    2015-10-01

    The primary challenge of rocket propulsion is the burden of needing to accelerate the spacecraft’s own fuel, resulting in only a logarithmic gain in maximum speed as propellant is added to the spacecraft. Light sails offer an attractive alternative in which fuel is not carried by the spacecraft, with acceleration being provided by an external source of light. By artificially illuminating the spacecraft with beamed radiation, speeds are only limited by the area of the sail, heat resistance of its material, and power use of the accelerating apparatus. In this paper, we show that leakage from a light sail propulsion apparatus in operation around a solar system analogue would be detectable. To demonstrate this, we model the launch and arrival of a microwave beam-driven light sail constructed for transit between planets in orbit around a single star, and find an optimal beam frequency on the order of tens of GHz. Leakage from these beams yields transients with flux densities of Jy and durations of tens of seconds at 100 pc. Because most travel within a planetary system would be conducted between the habitable worlds within that system, multiply transiting exoplanetary systems offer the greatest chance of detection, especially when the planets are in projected conjunction as viewed from Earth. If interplanetary travel via beam-driven light sails is commonly employed in our galaxy, this activity could be revealed by radio follow-up of nearby transiting exoplanetary systems. The expected signal properties define a new strategy in the search for extraterrestrial intelligence (SETI)

  19. Fluid-structure interaction analysis of deformation of sail of 30-foot yacht

    Directory of Open Access Journals (Sweden)

    Sera Bak

    2013-06-01

    Full Text Available Most yacht sails are made of thin fabric, and they have a cambered shape to generate lift force; however, their shape can be easily deformed by wind pressure. Deformation of the sail shape changes the flow characteristics over the sail, which in turn further deforms the sail shape. Therefore, fluid-structure interaction (FSI analysis is applied for the precise evaluation or optimization of the sail design. In this study, fluid flow analyses are performed for the main sail of a 30-foot yacht, and the results are applied to loading conditions for structural analyses. By applying the supporting forces from the rig, such as the mast and boom-end outhaul, as boundary conditions for structural analysis, the deformed sail shape is identified. Both the flow analyses and the structural analyses are iteratively carried out for the deformed sail shape. A comparison of the flow characteristics and surface pressures over the deformed sail shape with those over the initial shape shows that a considerable difference exists between the two and that FSI analysis is suitable for application to sail design.

  20. A discrete approach to modelling helicopter blade sailing

    Science.gov (United States)

    Wall, Alanna

    Blade sailing is an aeroelastic phenomenon which can occur during the engage and disengage phases of shipboard operations. This phenomenon is characterized by large blade deflections which are known to occur mainly at low rotor rotational speeds in high wind and sea conditions. Proper examination of this phenomenon requires adequate modelling of many contributing factors, including system dynamics, ship motion, airwake modelling, and aerodynamics. The research encompassed in this thesis sought to achieve a greater understanding of the factors that affect the blade sailing phenomenon through numerical modelling of the system as a whole. Novel models for system dynamics and ship airwake were developed under this research programme. The dynamic model is comprised of a series of rigid segments, which allows the analyst to completely define the parameters of the system, including number of blades and blade segments. The model also allows the inclusion of coupled stiffness terms, and a method for calculating the equivalent lumped stiffnesses from continuous coupled stiffness distributions. The numerical model was shown to capture non-linear, coupled, flexible beam bending behaviour through validation against published experimental data and analytical models. The airwake model is based on experimental data, and incorporates changing mean and turbulent flow characteristics over the flight deck in space, time, and with ship deck roll angle. The experimental research showed that ship motion changes the airwake significantly. A novel approach to the modelling of spatially- and temporally-correlated turbulence was developed, which recreates the time history of turbulent velocity fluctuations as experienced by a specific point on the rotating blade. Using these and previously developed models for ship motion and for blade aerodynamics, a comprehensive model of the system was developed and validated in combined blade sailing-like conditions through experiment. The results of the

  1. EMMI-Electric solar wind sail facilitated Manned Mars Initiative

    Science.gov (United States)

    Janhunen, Pekka; Merikallio, Sini; Paton, Mark

    2015-08-01

    The novel propellantless electric solar wind sail concept promises efficient low thrust transportation in the Solar System outside Earth's magnetosphere. Combined with asteroid mining to provide water and synthetic cryogenic rocket fuel in orbits of Earth and Mars, possibilities for affordable continuous manned presence on Mars open up. Orbital fuel and water enable reusable bidirectional Earth-Mars vehicles for continuous manned presence on Mars and allow smaller fuel fraction of spacecraft than what is achievable by traditional means. Water can also be used as radiation shielding of the manned compartment, thus reducing the launch mass further. In addition, the presence of fuel in the orbit of Mars provides the option for an all-propulsive landing, thus potentially eliminating issues of heavy heat shields and augmenting the capability of pinpoint landing. With this E-sail enabled scheme, the recurrent cost of continuous bidirectional traffic between Earth and Mars might ultimately approach the recurrent cost of running the International Space Station, ISS.

  2. Multi-Objective Weather Routing of Sailing Vessels

    Directory of Open Access Journals (Sweden)

    Życzkowski Marcin

    2017-12-01

    Full Text Available The paper presents a multi-objective deterministic method of weather routing for sailing vessels. Depending on a particular purpose of sailboat weather routing, the presented method makes it possible to customize the criteria and constraints so as to fit a particular user’s needs. Apart from a typical shortest time criterion, safety and comfort can also be taken into account. Additionally, the method supports dynamic weather data: in its present version short-term, mid-term and long-term term weather forecasts are used during optimization process. In the paper the multi-objective optimization problem is first defined and analysed. Following this, the proposed method solving this problem is described in detail. The method has been implemented as an online SailAssistance application. Some representative examples solutions are presented, emphasizing the effects of applying different criteria or different values of customized parameters.

  3. Electric sail elliptic displaced orbits with advanced thrust model

    Science.gov (United States)

    Niccolai, Lorenzo; Quarta, Alessandro A.; Mengali, Giovanni

    2017-09-01

    This paper analyzes the performance of an Electric Solar Wind Sail for generating and maintaining an elliptic, heliocentric, displaced non-Keplerian orbit. In this sense, this paper extends and completes recent studies regarding the performances of an Electric Solar Wind Sail that covers a circular, heliocentric, displaced orbit of given characteristics. The paper presents the general equations that describe the elliptic orbit maintenance in terms of both spacecraft attitude and performance requirements, when a refined thrust model (recently proposed for the preliminary mission design) is taken into account. In particular, the paper also discusses some practical applications on particular mission scenarios in which an analytic solution of the governing equations has been found.

  4. Visual Search Strategy During Regatta Starts in a Sailing Simulation.

    Science.gov (United States)

    Manzanares, Aaron; Menayo, Ruperto; Segado, Francisco

    2017-10-01

    In a sport conditioned by natural elements such as sailing, visual perception is a key factor for the performance. Research has shown that the visual behavior of athletes at different skill levels varies, which may cause differences in the performance achieved. The aim of this research was to examine the visual behavior of sailors from different ranking positions at the start of a race in a simulated situation. Twenty junior sailors (N = 10 top and N = 10 bottom ranking) participated in this study. The visual behavior was recorded at the start of a sailing simulation. The top-ranking sailors performed more visual fixations on the locations that have more highly relevant information, such as "telltales" and "rivals," than do bottom-ranking sailors (p visual search strategy shows that top-ranking sailors employed a more active visual search strategy. More experienced athletes can make better use of the information obtained from the important locations.

  5. Fast Solar Sailing Astrodynamics of Special Sailcraft Trajectories

    CERN Document Server

    Vulpetti, Giovanni

    2013-01-01

    The range of solar sailing is very vast; it is a fully in-space means of propellantless propulsion that should allow us to accomplish various mission classes that are unviable using near or medium-term rocket propulsion, no matter if nuclear or electric. Fast and very fast solar sailings are special classes of sailcraft missions, initially developed only in the first half of the 1990s and still evolving, especially after the latest advances in nanotechnology.   This book describes how to plan, compute and optimize the trajectories of sailcraft with speeds considerably higher than the Earth’s orbital speed (30 km/s); such sailcraft would be able to explore the outer heliosphere, the near interstellar medium and the solar gravitational lens (550-800 astronomical units) in times significantly shorter than the span of an average career (~ 35 years), just to cite a few examples. The scientific interest in this type of exploration is huge.

  6. Harvesting Near Earth Asteroid Resources Using Solar Sail Technology

    OpenAIRE

    McInnes, Colin

    2017-01-01

    Near Earth asteroids represent a wealth of material resources to support future space ventures. These resources include water from C-type asteroids for crew logistic support; liquid propellants electrolytically cracked from water to fuel crewed vehicles and commercial platforms; and metals from M-type asteroids to support in-situ manufacturing. In this paper the role of solar sail technology will be investigated to support the future harvesting of near Earth asteroid resources. This will incl...

  7. Hydrodynamics of sailing of the Portuguese man-of-war Physalia physalis

    OpenAIRE

    Iosilevskii, G.; Weihs, D.

    2008-01-01

    Physalia physalis, commonly known as the Portuguese man-of-war (PMW), is a peculiar looking colony of specialized polyps. The most conspicuous members of this colony are the gas-filled sail-like float and the long tentacles, budding asymmetrically beneath the float. This study addresses the sailing of the PMW, and, in particular, the hydrodynamics of its trailing tentacles, the interaction between the tentacles and the float and the actual sailing performance. This paper attempts to provide a...

  8. Near Earth Asteroid Scout Solar Sail Engineering Development Unit Test Suite

    Science.gov (United States)

    Lockett, Tiffany Russell; Few, Alexander; Wilson, Richard

    2017-01-01

    The Near Earth Asteroid (NEA) Scout project is a 6U reconnaissance mission to investigate a near Earth asteroid utilizing an 86m(sub 2) solar sail as the primary propulsion system. This will be the largest solar sail NASA has launched to date. NEA Scout is currently manifested on the maiden voyage of the Space Launch System in 2018. In development of the solar sail subsystem, design challenges were identified and investigated for packaging within a 6U form factor and deployment in cis-lunar space. Analysis was able to capture understanding of thermal, stress, and dynamics of the stowed system as well as mature an integrated sail membrane model for deployed flight dynamics. Full scale system testing on the ground is the optimal way to demonstrate system robustness, repeatability, and overall performance on a compressed flight schedule. To physically test the system, the team developed a flight sized engineering development unit with design features as close to flight as possible. The test suite included ascent vent, random vibration, functional deployments, thermal vacuum, and full sail deployments. All of these tests contributed towards development of the final flight unit. This paper will address several of the design challenges and lessons learned from the NEA Scout solar sail subsystem engineering development unit. Testing on the component level all the way to the integrated subsystem level. From optical properties of the sail material to fold and spooling the single sail, the team has developed a robust deployment system for the solar sail. The team completed several deployments of the sail system in preparation for flight at half scale (4m) and full scale (6.8m): boom only, half scale sail deployment, and full scale sail deployment. This paper will also address expected and received test results from ascent vent, random vibration, and deployment tests.

  9. Climate Odyssey: Communicating Coastal Change through Art, Science, and Sail

    Science.gov (United States)

    Klos, P. Z.; Holtsnider, L.

    2016-12-01

    Climate Odyssey (climateodyssey.org) is a year-long sailing expedition and continuing collaboration aimed at using overlaps in science and visual art to communicate coastal climate change impacts and solutions. We, visual artist Lucy Holtsnider and climate scientist Zion Klos, are using our complimentary skills in art, science and communication to engage audiences both affectively and cognitively regarding the urgency of climate change through story and visualization. In July of 2015, we embarked on the sailing portion of Climate Odyssey, beginning in Lake Michigan, continuing along the Eastern Seaboard, and concluding in May 2016 in the tropics. Along the way we photographed climate change impacts and adaptation strategies, interviewed stakeholders, scientists, and artists. We are now sharing our photographs and documented encounters through a tangible artist's book, interactive digital map, and blog. Each of our images added to the artist's book and digital map are linked to relevant blog entries and other external scientific resources, making the map both an aesthetic piece of art and an engaging tool for sharing the science of climate change impacts and solutions. After completing the sailing component of the project, we are now working to finalize our media and share our pieces with the public via libraries, galleries, and classrooms in coastal communities. At AGU, we will share with our peers the completed version of the artist's book, digital map, and online blog so we can both discuss public engagement strategies and showcase this example of art-science outreach with the broader science communication community.

  10. Drift-free solar sail formations in elliptical Sun-synchronous orbits

    Science.gov (United States)

    Parsay, Khashayar; Schaub, Hanspeter

    2017-10-01

    To study the spatial and temporal variations of plasma in the highly dynamic environment of the magnetosphere, multiple spacecraft must fly in a formation. The objective for this study is to investigate the feasibility of solar sail formation flying in the Earth-centered, Sun-synchronous orbit regime. The focus of this effort is to enable formation flying for a group of solar sails that maintain a nominally fixed Sun-pointing attitude during formation flight, solely for the purpose of precessing their orbit apse lines Sun-synchronously. A fixed-attitude solar sail formation is motivated by the difficulties in the simultaneous control of orbit and attitude in flying solar sails. First, the secular rates of the orbital elements resulting from the effects of solar radiation pressure (SRP) are determined using averaging theory for a Sun-pointing attitude sail. These averaged rates are used to analytically derive the first-order necessary conditions for a drift-free solar sail formation in Sun-synchronous orbits, assuming a fixed Sun-pointing orientation for each sail in formation. The validity of the first-order necessary conditions are illustrated by designing quasi-periodic relative motions. Next, nonlinear programming is applied to design truly drift-free two-craft solar sail formations. Lastly, analytic expressions are derived to determine the long-term dynamics and sensitivity of the formation with respect to constant attitude errors, uncertainty in orbital elements, and uncertainty in a sail's characteristic acceleration.

  11. On Motion Planning for Point-to-Point Maneuvers for a Class of Sailing Vehicles

    DEFF Research Database (Denmark)

    Xiao, Lin; Jouffroy, Jerome

    2011-01-01

    Despite their interesting dynamic and controllability properties, sailing vehicles have not been much studied in the control community. In this paper, we investigate motion planning of such vehicles. Starting from a simple dynamic model of sailing vessels in one dimension, this paper first...... considers their associated controllability issues, with the so-called no-sailing zone as a starting point, and it links them with a motion planning strategy using two-point boundary value problems as the main mathematical tool. This perspective is then expanded to do point-to-point maneuvers of sailing...

  12. Traditional Sailing Ships as Indigenous Dalmatian Nautical Product

    Directory of Open Access Journals (Sweden)

    Srećko Favro

    2015-10-01

    Full Text Available Modern tourist movements of the development of selective tourism forms have offered an opportunity to implement the valorisation of Croatian littoral area through the development of nautical tourism in all its forms, cruising included. As opposed to international cruise market, where the main word have cruisers with few hundred to several thousand passengers, a special type of multi-day cruising or excursion cruising along Croatian coast on traditional Croatian sailing ships has significantly developed in the last few years. Wooden sailing ships have a magical power to attract. They won’t pass unnoticed regardless a huge competition of new trends in constructing technologically perfect modern mega-yachts and the most sophisticated mega-cruisers. In this paper, several traditional sailing ships will be described. They were primary intended to transport cargo, and today they’re renovated with saloons, kitchens, toilets, bathrooms, air-conditioners and satellite TV receivers. Modern usage of this, for Croatian culture, important indigenous product promotes specificities of Croatian maritime and shipbuilding tradition, creates recognition and authenticity of nautical tourism in Croatia and creates also numerous other positive effects such as promotion of middle and small shipbuilding and employment of local inhabitants on islands that at the same time prevents their depopulation. In order to achieve full potential of this form of Croatian nautical offer it is necessary to invest and to motivate main carriers of activities – small ship owners. Besides the need for economic incentives, it is also very important a joint defining of maritime routes for touristic cruising in the way to select ports that, with the state support, would be renovated to accept cruisers. It is also necessary to set a system of planned cruises and berth reservations by a careful selection of favourable locations. This would enable organisation stages and coordination

  13. Living at Sea: Learning from Communal Life Aboard Sail Training Vessels

    Science.gov (United States)

    McCulloch, Ken

    2007-01-01

    This paper considers features of domestic and social life aboard sail training vessels, exploring the particular character of life at sea, and how these features contribute to the distinctive character of sail training experience as a context for learning. Methodologically, the study lies in the sociological tradition of ethnography, focusing on…

  14. A control-theoretic outlook at the no-go zone in sailing vessels

    DEFF Research Database (Denmark)

    Yang, Bin; Xiao, Lin; Jouffroy, Jerome

    2011-01-01

    Sailing vessels, due to their particular propulsive mechanism, gradually lose power as they face the wind, i.e. when they are in the so-called “no-go zone”. Interestingly, dynamical models of sailing vessels, which are usually quite complex, all have in common this no-go zone effect. Using a cont...

  15. Extension of Earth-Moon libration point orbits with solar sail propulsion

    NARCIS (Netherlands)

    Heiligers, M.J.; Macdonald, Malcolm; Parker, Jeffrey S.

    2016-01-01

    This paper presents families of libration point orbits in the Earth-Moon system that originate from complementing the classical circular restricted three-body problem with a solar sail. Through the use of a differential correction scheme in combination with a continuation on the solar sail

  16. The effect of motion on presence during virtual sailing for advanced training

    NARCIS (Netherlands)

    Mulder, F.A.; Verlinden, J.C.; Dukalski, R.R.

    This paper explores the amount of motion simulation required to influence presence and immersion on a dinghy sailing simulator. We specifically focused on the effects of roll, pitch and heave, when sailing an course with up-, side-and down-wind sections in a virtual environment. A real dingy was

  17. Characterization of Candidate Solar Sail Material Exposed to Space Environmental Effects

    Science.gov (United States)

    Edwards, David; Hovater, Mary; Hubbs, Whitney; Wertz, George; Hollerman, William; Gray, Perry

    2003-01-01

    Solar sailing is a unique form of propulsion where a spacecraft gains momentum from incident photons. Solar sails are not limited by reaction mass and provide continual acceleration, reduced only by the lifetime of the lightweight film in the space environment and the distance to the Sun. Once thought to be difficult or impossible, solar sailing has come out of science fiction and into the realm of possibility. Any spacecraft using this method would need to deploy a thin sail that could be as large as many kilometers in extent. The availability of strong, ultra lightweight, and radiation resistant materials will determine the future of solar sailing. The National Aeronautics and Space Administration's Marshall Space Flight Center (MSFC) is concentrating research into the utilization of ultra lightweight materials for spacecraft propulsion. The Space Environmental Effects Team at MSFC is actively characterizing candidate solar sail material to evaluate the thermo-optical and mechanical properties after exposure to space environmental effects. This paper will describe the exposure of candidate solar sail materials to emulated space environmental effects including energetic electrons, combined electrons and Ultraviolet radiation, and hypervelocity impact of irradiated solar sail material. This paper will describe the testing procedure and the material characterization results of this investigation.

  18. 76 FR 43893 - Special Local Regulations; Port Huron to Mackinac Island Sail Race

    Science.gov (United States)

    2011-07-22

    ... Sail Race AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard will establish a temporary special local regulation for the annual Port Huron to Mackinac Island Sail Race. This action is necessary to safely control vessel movements in the vicinity of the race's starting point and...

  19. The sail wing windmill and its adaptation for use in rural India

    Science.gov (United States)

    Sherman, M. M.

    1973-01-01

    An 8 meter-diameter prototype sail wing windmill is reported that uses a one meter-diameter bullock cartwheel to which three bamboo poles are latched in a triangular pattern with overlapping ends, to form the airframe for cloth sails. This device lifts 300 pounds to a height of 20 feet in one minute in a 10 mph wind.

  20. Attitude and Translation Control of a Solar Sail Vehicle

    Science.gov (United States)

    Singh, Gurkirpal

    2008-01-01

    A report discusses the ability to control the attitude and translation degrees-of-freedom of a solar sail vehicle by changing its center of gravity. A movement of the spacecraft s center of mass causes solar-pressure force to apply a torque to the vehicle. At the compact core of the solar-sail vehicle lies the spacecraft bus which is a large fraction of the total vehicle mass. In this concept, the bus is attached to the spacecraft by two single degree-of-freedom linear tracks. This allows relative movement of the bus in the sail plane. At the null position, the resulting solar pressure applies no torque to the vehicle. But any deviation of the bus from the null creates an offset between the spacecraft center of mass and center of solar radiation pressure, resulting in a solar-pressure torque on the vehicle which changes the vehicle attitude. Two of the three vehicle degrees of freedom can be actively controlled in this manner. The third, the roll about the sunline, requires a low-authority vane/propulsive subsystem. Translation control of the vehicle is achieved by directing the solar-pressure-induced force in the proper inertial direction. This requires attitude control. Attitude and translation degrees-of-freedom are therefore coupled. A guidance law is proposed, which allows the vehicle to stationkeep at an appropriate point on the inertially-rotating Sun-Earth line. Power requirements for moving the bus are minimal. Extensive software simulations have been performed to demonstrate the feasibility of this concept.

  1. Status of Solar Sail Propulsion Within NASA - Moving Toward Interstellar Travel

    Science.gov (United States)

    Johnson, Les

    2015-01-01

    NASA is developing solar sail propulsion for two near-term missions and laying the groundwork for their future use in deep space and interstellar precursor missions. Solar sails use sunlight to propel vehicles through space by reflecting solar photons from a large, mirror-like sail made of a lightweight, highly reflective material. This continuous photon pressure provides propellantless thrust, allowing for very high (Delta)V maneuvers on long-duration, deep space exploration. Since reflected light produces thrust, solar sails require no onboard propellant. The Near Earth Asteroid (NEA) Scout mission, managed by MSFC, will use the sail as primary propulsion allowing it to survey and image one or more NEA's of interest for possible future human exploration. Lunar Flashlight, managed by JPL, will search for and map volatiles in permanently shadowed Lunar craters using a solar sail as a gigantic mirror to steer sunlight into the shaded craters. The Lunar Flashlight spacecraft will also use the propulsive solar sail to maneuver into a lunar polar orbit. Both missions use a 6U cubesat architecture, a common an 85 sq m solar sail, and will weigh less than 12 kilograms. Both missions will be launched on the first flight of the Space Launch System in 2018. NEA Scout and Lunar Flashlight will serve as important milestones in the development of solar sail propulsion technology for future, more ambitious missions including the Interstellar Probe - a mission long desired by the space science community which would send a robotic probe beyond the edge of the solar system to a distance of 250 Astronomical Units or more. This paper will summarize the development status of NEA Scout and Lunar Flashlight and describe the next steps required to enable an interstellar solar sail capability.

  2. Use of a Virtual-Technological Sailing Program to Prepare Children With Disabilities for a Real Sailing Course: Effects on Balance and Quality of Life.

    Science.gov (United States)

    Aprile, Irene; Iacovelli, Chiara; Iuvone, Laura; Imbimbo, Isabella; Cruciani, Arianna; Pecchioli, Cristiano; Manozzi, Francesco Maria; Padua, Luca

    2016-07-01

    Sailing might produce a positive effect on a patient's general health and become an integrated part of rehabilitation. Our hypothesis was that a specific technological rehabilitation program might be used to prepare a group of disabled subjects for sailing. Seventeen patients (age range: 9-20) with impairments in motor coordination and balance and 15 healthy subjects participated in the study. The study was divided into the virtual-technological sailing phase, theory-practice phase, and sports phase. Proprioceptive platforms were used to evaluate balance, and the Child Health Questionnaire-PF50 was used to evaluate quality of life. Trunk displacement and the center of pressure velocity improved significantly after the virtual-technological sailing program. As regards quality of life, the physical and psychosocial score significantly improved at the end of the program. A technological rehabilitation training improved balance in disabled subjects and may be used to prepare them for a real sailing course. Sailing improves the quality of life of disabled subjects and could be used in the rehabilitation. © The Author(s) 2016.

  3. Deployment Technology of a Heliogyro Solar Sail for Long Duration Propulsion

    Science.gov (United States)

    Peerawan, Wiwattananon; Bryant, Robert G.; Edmonson, William W.; Moore, William B.; Bell, Jared M.

    2015-01-01

    Interplanetary, multi-mission, station-keeping capabilities will require that a spacecraft employ a highly efficient propulsion-navigation system. The majority of space propulsion systems are fuel-based and require the vehicle to carry and consume fuel as part of the mission. Once the fuel is consumed, the mission is set, thereby limiting the potential capability. Alternatively, a method that derives its acceleration and direction from solar photon pressure using a solar sail would eliminate the requirement of onboard fuel to meet mission objectives. MacNeal theorized that the heliogyro-configured solar sail architecture would be lighter, less complex, cheaper, and less risky to deploy a large sail area versus a masted sail. As sail size increases, the masted sail requires longer booms resulting in increased mass, and chaotic uncontrollable deployment. With a heliogyro, the sail membrane is stowed as a roll of thin film forming a blade when deployed that can extend up to kilometers. Thus, a benefit of using a heliogyro-configured solar sail propulsion technology is the mission scalability as compared to masted versions, which are size constrained. Studies have shown that interplanetary travel is achievable by the heliogyro solar sail concept. Heliogyro solar sail concept also enables multi-mission missions such as sample returns, and supply transportation from Earth to Mars as well as station-keeping missions to provide enhanced warning of solar storm. This paper describes deployment technology being developed at NASA Langley Research Center to deploy and control the center-of-mass/center-of-pressure using a twin bladed heliogyro solar sail 6-unit (6U) CubeSat. The 6U comprises 2x2U blade deployers and 2U for payload. The 2U blade deployers can be mounted to 6U or larger scaled systems to serve as a non-chemical in-space propulsion system. A single solar sail blade length is estimated to be 2.4 km with a total area from two blades of 720 m2; total allowable weight

  4. Extrasolar solar-sail trajectories and dark matter

    Science.gov (United States)

    Matloff, Gregory L.

    2014-11-01

    Hyper-thin, high-speed solar-photon sail space probes exploring the Sun's Oort comet cloud could also be used to set an upper bound to the concentration of WIMPS (weakly interacting massive particles), one of the suggested (but unconfirmed) forms of dark matter within the vicinity of the solar system. Newton's Shell Theorem would be applied to determine variations in apparent solar mass as the probe moves further out from the Sun. Application of this technique to the trajectories of Pioneer 10/11 reveals that the upper limit to WIMP concentration within ~60 AU of the Sun is ~0.2 Earth masses, as revealed in studies of the Pioneer Anomaly. If the published accuracy of the Pioneer acceleration measurements can be increased by an order of magnitude, probe trajectory measurements out to ~10,000 AU may confirm or falsify the hypothesis that WIMP mass within the solar vicinity is ~3X star mass. It is shown that a space-manufactured ~40-nm thick beryllium hollow-body solar sail deployed from a ~0.07 AU perihelion is a candidate spacecraft for such a mission. Possible science-team organization strategy for a ~100-year mission to ~10,000 AU is discussed.

  5. Attitude Dynamics, Stability, and Control of a Heliogyro Solar Sail

    Science.gov (United States)

    Pimienta-Penalver, Adonis Reinier

    A heliogyro solar sail concept, dubbed `HELIOS', is proposed as an alternative to deep space missions without the need for on-board propellant. Although this type of solar sail has existed in concept for several decades, and some previous studies have investigated certain aspects of its operation, a significant amount of research is still needed to analyze the dynamic and control characteristics of the structure under the projected range of orbital conditions. This work presents an improvement upon the existing discrete-mass models of the heliogyro blade, and the extension of its application from a single membrane blade to a fully-coupled approximation of the dynamics of the HELIOS system with multiple spinning membrane blades around a central hub. The incorporation of structural stiffness and external forcing effects into the model is demonstrated to add a further degree of fidelity in simulating the stability properties of the system. Additionally, the approximated dynamics of multiple-blade heliogyro structures are examined under the effect of solar radiation pressure. Lastly, this study evaluates a control algorithm at each blade root to impose structural integrity and attitude control by coordinating well-known helicopter blade pitching profiles.

  6. Rethinking Use of the OML Model in Electric Sail Development

    Science.gov (United States)

    Stone, Nobie H.

    2016-01-01

    In 1924, Irvin Langmuir and H. M. Mott-Smith published a theoretical model for the complex plasma sheath phenomenon in which they identified some very special cases which greatly simplified the sheath and allowed a closed solution to the problem. The most widely used application is for an electrostatic, or "Langmuir," probe in laboratory plasma. Although the Langmuir probe is physically simple (a biased wire) the theory describing its functional behavior and its current-voltage characteristic is extremely complex and, accordingly, a number of assumptions and approximations are used in the LMS model. These simplifications, correspondingly, place limits on the model's range of application. Adapting the LMS model to real-life conditions is the subject of numerous papers and dissertations. The Orbit-Motion Limited (OML) model that is widely used today is one of these adaptions that is a convenient means of calculating sheath effects. Since the Langmuir probe is a simple biased wire immersed in plasma, it is particularly tempting to use the OML equation in calculating the characteristics of the long, highly biased wires of an Electric Sail in the solar wind plasma. However, in order to arrive at the OML equation, a number of additional simplifying assumptions and approximations (beyond those made by Langmuir-Mott-Smith) are necessary. The OML equation is a good approximation when all conditions are met, but it would appear that the Electric Sail problem lies outside of the limits of applicability.

  7. Sail Plan Configuration Optimization for a Modern Clipper Ship

    Science.gov (United States)

    Gerritsen, Margot; Doyle, Tyler; Iaccarino, Gianluca; Moin, Parviz

    2002-11-01

    We investigate the use of gradient-based and evolutionary algorithms for sail shape optimization. We present preliminary results for the optimization of sheeting angles for the rig of the future three-masted clipper yacht Maltese Falcon. This yacht will be equipped with square-rigged masts made up of yards of circular arc cross sections. This design is especially attractive for megayachts because it provides a large sail area while maintaining aerodynamic and structural efficiency. The rig remains almost rigid in a large range of wind conditions and therefore a simple geometrical model can be constructed without accounting for the true flying shape. The sheeting angle optimization studies are performed using both gradient-based cost function minimization and evolutionary algorithms. The fluid flow is modeled by the Reynolds-averaged Navier-Stokes equations with the Spallart-Allmaras turbulence model. Unstructured non-conforming grids are used to increase robustness and computational efficiency. The optimization process is automated by integrating the system components (geometry construction, grid generation, flow solver, force calculator, optimization). We compare the optimization results to those done previously by user-controlled parametric studies using simple cost functions and user intuition. We also investigate the effectiveness of various cost functions in the optimization (driving force maximization, ratio of driving force to heeling force maximization).

  8. Extension of Earth-Moon libration point orbits with solar sail propulsion

    Science.gov (United States)

    Heiligers, Jeannette; Macdonald, Malcolm; Parker, Jeffrey S.

    2016-07-01

    This paper presents families of libration point orbits in the Earth-Moon system that originate from complementing the classical circular restricted three-body problem with a solar sail. Through the use of a differential correction scheme in combination with a continuation on the solar sail induced acceleration, families of Lyapunov, halo, vertical Lyapunov, Earth-centred, and distant retrograde orbits are created. As the solar sail circular restricted three-body problem is non-autonomous, a constraint defined within the differential correction scheme ensures that all orbits are periodic with the Sun's motion around the Earth-Moon system. The continuation method then starts from a classical libration point orbit with a suitable period and increases the solar sail acceleration magnitude to obtain families of orbits that are parametrised by this acceleration. Furthermore, different solar sail steering laws are considered (both in-plane and out-of-plane, and either fixed in the synodic frame or fixed with respect to the direction of Sunlight), adding to the wealth of families of solar sail enabled libration point orbits presented. Finally, the linear stability properties of the generated orbits are investigated to assess the need for active orbital control. It is shown that the solar sail induced acceleration can have a positive effect on the stability of some orbit families, especially those at the L2 point, but that it most often (further) destabilises the orbit. Active control will therefore be needed to ensure long-term survivability of these orbits.

  9. [Investigation of the prevalence of periodontal diseases among naval personnel during prolonged sailing].

    Science.gov (United States)

    Zhao, Zheng; Li, Lu-Jia; Huang, Zheng-Nan; Jia, Bao-Jun; Yang, Hai-Qing

    2015-02-01

    To investigate the prevalence of periodontal diseases among naval personnel during prolonged sailing. The calculus index-simplified (CI-S), plaque index (PLI), gingival index (GI), community periodontal index (CPI), attachment loss (AL), number of missing tooth (NMT) and prevalence of periodontal disease were recorded among 186 naval personnel who participated in prolonged sailing before and after sailing. The data was analyzed with SPSS 14.0 software package. Each periodontal index after sailing was significantly higher than that of before sailing(Pperiodontal diseases from 186 objects was 59.7%; While after sailing the prevalence increased to 83.3%. Among them, patients who suffered from gingivitis and mid or moderate periodontitis raised greatly, and significant differences were found in the prevalence and degree of periodontal disease (Pperiodontal state of naval personnel. To enhance propaganda and education on oral hygiene promptly and effectively, to develop the habit of correct toothbrushing, to have balanced and rational diet, and to perform proper periodontal non-surgical treatment and medication are essential to periodontal health of naval personnel during prolonged sailing.

  10. Near Earth Asteroid Scout: NASA's Solar Sail Mission to a NEA

    Science.gov (United States)

    Johnson, Les; Castillo-Rogez, Julie; Dervan, Jared

    2017-01-01

    NASA is developing a solar sail propulsion system for use on the Near Earth Asteroid (NEA) Scout reconnaissance mission and laying the groundwork for their use in future deep space science and exploration missions. Solar sails use sunlight to propel vehicles through space by reflecting solar photons from a large, mirror-like sail made of a lightweight, highly reflective material. This continuous photon pressure provides propellant-less thrust, allowing for very high delta V maneuvers on long-duration, deep space exploration. Since reflected light produces thrust, solar sails require no onboard propellant. The Near Earth Asteroid (NEA) Scout mission, funded by NASA’s Advanced Exploration Systems Program and managed by NASA MSFC, will use the sail as primary propulsion allowing it to survey and image Asteroid 1991VG and, potentially, other NEA’s of interest for possible future human exploration. The NEA Scout spacecraft is housed in a 6U CubeSat-form factor and utilizes an 86 square meter solar sail for a total mass less than 14 kilograms. The mission is in partnership with the Jet Propulsion Laboratory with support from Langley Research Center and science participants from various institutions. NEA Scout will be launched on the maiden flight of the Space Launch System in 2019. The solar sail for NEA Scout will be based on the technology developed and flown by the NASA NanoSail-D and flown on The Planetary Society’s Lightsail-A. Four approximately-7-meter stainless steel booms wrapped on two spools (two overlapping booms per spool) will be motor driven and pull the sail from its stowed volume. The sail material is an aluminized polyimide approximately 2.5 microns thick. As the technology matures, solar sails will increasingly be used to enable science and exploration missions that are currently impossible or prohibitively expensive using traditional chemical and electric propulsion systems. This paper will summarize the status of the NEA Scout mission and solar

  11. A control strategy for steering an autonomous surface sailing vehicle in a tacking maneuver

    DEFF Research Database (Denmark)

    Jouffroy, Jerome

    2009-01-01

    Sailing vessels such as sailboats but also landyachts are vehicles representing a real challenge for automation. However, the control aspects of such vehicles were hitherto very little studied. This paper presents a simplied dynamic model of a so-called landyacht allowing to capture the main...... elements of the behavior of surface sailing vessels. We then propose a path generation scheme and a controller design for a well-known and fundamental maneuver in sailing referred to as tacking. Simulation results are presented to illustrate the approach....

  12. Deorbiting Upper-Stages in LEO at EOM using Solar Sails

    Directory of Open Access Journals (Sweden)

    Alexandru IONEL

    2017-06-01

    Full Text Available This paper analyzes the possibility of deorbiting a launch vehicle upper-stage at end-of-mission from low Earth orbit through the use of a solar sail. Different solar sail sizes are taken into account. The analysis is made via a MATLAB numerical simulation, integrating with the ode45 solver the accelerations arising from geopotential, atmospheric drag and solar radiation pressure. Direct solar pressure and drag augmentation effect are analyzed and a state of the art study in the solar sail research field is performed for a better grasp of the feasibility of the device implementation.

  13. Reflexions on feedforward control strategies for a class of sailing vehicles

    DEFF Research Database (Denmark)

    Xiao, Lin; Jouffroy, Jerome

    2010-01-01

    Sailing vehicles, whether they are sea or land-based, share the unique property of exhibiting totally different trajectories depending on where their direction of travel is with respect to the wind. Following our previous work, this paper discusses a few points related to feedforward control...... and motion planning of surface sailing vehicles. More specifically, we examine the interplay between simple controllability reasonings and motion planning. These few remarks are used in a constructive way for automatic generation of start/stop maneuvers of a simple model of sailing vehicles. Simulation...

  14. Conceptual Design of an Electric Sail Technology Demonstration Mission Spacecraft

    Science.gov (United States)

    Wiegmann, Bruce M.

    2017-01-01

    There is great interest in examining the outer planets of our solar system and Heliopause region (edge of Solar System) and beyond regions of interstellar space by both the Planetary and Heliophysics communities. These needs are well docu-mented in the recent National Academy of Sciences Decadal Surveys. There is significant interest in developing revolutionary propulsion techniques that will enable such Heliopause scientific missions to be completed within 10 to15 years of the launch date. One such enabling propulsion technique commonly known as Electric Sail (E-Sail) propulsion employs positively charged bare wire tethers that extend radially outward from a rotating spacecraft spinning at a rate of one revolution per hour. Around the positively charged bare-wire tethers, a Debye Sheath is created once positive voltage is applied. This sheath stands off of the bare wire tether at a sheath diameter that is proportional to the voltage in the wire coupled with the flux density of solar wind ions within the solar system (or the location of spacecraft in the solar system. The protons that are expended from the sun (solar wind) at 400 to 800 km/sec are electrostatically repelled away from these positively charged Debye sheaths and propulsive thrust is produced via the resulting momentum transfer. The amount of thrust produced is directly proportional to the total wire length. The Marshall Space Flight Center (MSFC) Electric Sail team is currently funded via a two year Phase II NASA Innovative Advanced Concepts (NIAC) awarded in July 2015. The team's current activities are: 1) Developing a Particle in Cell (PIC) numeric engineering model from the experimental data collected at MSFC's Solar Wind Facility on the interaction between simulated solar wind interaction with a charged bare wire that can be applied to a variety of missions, 2) The development of the necessary tether deployers and tethers to enable successful de-ployment of multiple, multi km length bare tethers

  15. Shape memory self-deployable structures for solar sails

    Science.gov (United States)

    Sokolowski, Witold; Tan, Seng; Willis, Paul; Pryor, Mark

    2008-12-01

    A cold-hibernated elastic memory (CHEM) structures technology is one of the most recent results of the quest for simple, reliable and low-cost self-deployable structures. The CHEM technology utilizes shape-memory polymers in open-cell foam structures or sandwich structures made of shape-memory-polymer foam cores and polymeric laminated-composite skins. It takes advantage of a polymer's shape memory and the corresponding internal elastic recovery forces to self-deploy a compacted structure. This paper describes these structures and their major advantages over other expandable and deployable structures presently used. Previous preliminary investigations and experiments have confirmed the feasibility of certain CHEM structures for space applications. Further improvements in CHEM technology and structure design widen potential space applications, including advanced solar sail structural concepts that are revealed and described in this paper.

  16. Sailing the skies: the improbable aeronautical success of the pterosaurs.

    Science.gov (United States)

    Wilkinson, Matthew T

    2007-05-01

    Pterosaur wings bore a striking resemblance to sails, having a bony spar at the leading edge, formed by the forelimb and one enormously elongated digit, and an elastic wing membrane. Such simple wings would be expected to have performed badly due to excessive deformation, membrane flutter and poor control characteristics. Here I discuss how certain anatomical features, specifically a forewing membrane in the inner part of the wing and a system of fibres embedded in the distal part, may have countered these shortcomings. The forewing, supported by the unique pteroid bone, would have reduced the wings' geometric twist, and has been shown in wind tunnel tests to improve membrane stability at low angles of attack and dramatically increase the maximum lift coefficient at high angles of attack. The function of the fibres is poorly understood, but it is suggested that they improved membrane stability and optimised twist nearer the wingtips.

  17. Temperature-Driven Shape Changes of the Near Earth Asteroid Scout Solar Sail

    Science.gov (United States)

    Stohlman, Olive R.; Loper, Erik R.; Lockett, Tiffany E.

    2017-01-01

    Near Earth Asteroid Scout (NEA Scout) is a NASA deep space Cubesat, scheduled to launch on the Exploration Mission 1 flight of the Space Launch System. NEA Scout will use a deployable solar sail as its primary propulsion system. The sail is a square membrane supported by rigid metallic tapespring booms, and analysis predicts that these booms will experience substantial thermal warping if they are exposed to direct sunlight in the space environment. NASA has conducted sunspot chamber experiments to confirm the thermal distortion of this class of booms, demonstrating tip displacement of between 20 and 50 centimeters in a 4-meter boom. The distortion behavior of the boom is complex and demonstrates an application for advanced thermal-structural analysis. The needs of the NEA Scout project were supported by changing the solar sail design to keep the booms shaded during use of the solar sail, and an additional experiment in the sunspot chamber is presented in support of this solution.

  18. On Motion Planning for Point-to-Point Maneuvers for a Class of Sailing Vehicles

    Directory of Open Access Journals (Sweden)

    Lin Xiao

    2011-01-01

    Full Text Available Despite their interesting dynamic and controllability properties, sailing vehicles have not been much studied in the control community. In this paper, we investigate motion planning of such vehicles. Starting from a simple dynamic model of sailing vessels in one dimension, this paper first considers their associated controllability issues, with the so-called no-sailing zone as a starting point, and it links them with a motion planning strategy using two-point boundary value problems as the main mathematical tool. This perspective is then expanded to do point-to-point maneuvers of sailing vehicles in the plane, that is, automatic path generation combined with computation of control input profiles. Simulations are presented to illustrate the potential of the approach.

  19. Motives for participation in Paralympic sailing – opinions of Polish and foreign athletes with physical disabilities

    National Research Council Canada - National Science Library

    Grzegorz Prokopowicz; Bartosz Molik; Katarzyna Prokopowicz; Tomasz Chamera; Anna Ogonowska-Słodownik; Judit Lencse-Mucha; Natalia Morgulec-Adamowicz; Andrzej Kosmol; Krzysztof Perkowski

    2016-01-01

    .... Currently, disabled athletes can compete in three classes: Sonar, 2.4mR and Skud 18. The review of the Polish and foreign literature does not give a clear indication of the motives for participation in Paralympic sailing...

  20. Flex Dynamics Avoidance Control of the NEA Scout Solar Sail Spacecraft's Reaction Control System

    Science.gov (United States)

    Heaton Andrew; Stiltner, Brandon; Diedrich, Benjamin; Becker, Christopher; Orphee, Juan

    2017-01-01

    The Attitude Control System (ACS) is developed for a Near Earth Asteroid (NEA) Scout mission using a solar sail. The NEA-Scout spacecraft is a 6U cubesat with an 86 square-meter solar sail. NEA Scout will launch on Space Launch System (SLS) Exploration Mission 1 (EM-1), currently scheduled to launch in 2018. The spacecraft will rendezvous with a target asteroid after a two year journey, and will conduct science imagery. The solar sail spacecraft ACS consists of three major actuating subsystems: a Reaction Wheel (RW) control system, a Reaction Control System (RCS), and an Adjustable Mass Translator (AMT) system. The three subsystems allow for a wide range of spacecraft attitude control capabilities, needed for the different phases of the NEA-Scout mission. Because the sail is a flexible structure, care must be taken in designing a control system to avoid exciting the structural modes of the sail. This is especially true for the RCS, which uses pulse actuated, cold-gas jets to control the spacecraft's attitude. While the reaction wheels can be commanded smoothly, the RCS jets are simple on-off actuators. Long duration firing of the RCS jets - firings greater than one second - can be thought of as step inputs to the spacecraft's torque. On the other hand, short duration firings - pulses on the order of 0.1 seconds - can be thought of as impulses in the spacecraft's torque. These types of inputs will excite the structural modes of the spacecraft, causing the sail to oscillate. Sail oscillations are undesirable for many reasons. Mainly, these oscillations will feed into the spacecraft attitude sensors and pointing accuracy, and long term oscillations may be undesirable over the lifetime of the solar sail. In order to limit the sail oscillations, an RCS control scheme is being developed to minimize sail excitations. Specifically, an input shaping scheme similar to the method described in Reference 1 will be employed. A detailed description of the RCS control scheme will

  1. Determination of effective solar pressure force on the deformed heliogyro solar sail

    Directory of Open Access Journals (Sweden)

    V. N. Zimin

    2016-01-01

    Full Text Available This paper presents a review of the references on solar sails, which implies that this subject is relevant and actively developed by various researchers from around the globe. It points out that an important role is played by various imperfections, which would affect the parameters of real solar sails compared to the ideal model.The differential equilibrium equations of the blades of a heliogyro solar sail considering small deformations are written at the beginning of the article. The blade is loaded by light pressure and centrifugal forces, and is fixed at one end in the rotation axis while the other end is free. The differential equation for the blade deflection is obtained. This equation is solved in a statement that the reflection coefficient is independent on the mechanical stress. The deflection function has a simple analytical formulation. The differential equation for the transverse deflection of the solar sail blade is also solved analytically in the formulation of the linear dependence of the reflection coefficient on the tensile stress. The results obtained in both derivations are compared at the maximum amount of deflection of the blade of heliogyro solar sail. It is proved that the maximum difference in the magnitude of the deflection is achieved at tip section. An analytical expression for the relative change in the maximum deflection of the sail blades is given. The chart of this dependency is given for the blade of perspective solar sail with a length of 1000m and made from PET material, which is considered in the linear-elastic formulation.To calculate the projection of the resultant vector of light pressure on the axis of rotation the hypothesis is introduced that the decrease of the reflection coefficient of the material exactly equals to the increase in the transmittance, and vice versa. Considering this hypothesis for PET material the proportionality factor is found, showing a decrease of the reflection coefficient with

  2. Motives for participation in Paralympic sailing – opinions of Polish and foreign athletes with physical disabilities

    Directory of Open Access Journals (Sweden)

    Prokopowicz Grzegorz

    2016-09-01

    Full Text Available Introduction: Paralympic sailing was introduced at the Atlanta 1996 Paralympic Games. Since then it has been developing rapidly and an increasing number of individuals in Poland and abroad regularly take part in sports competitions. Currently, disabled athletes can compete in three classes: Sonar, 2.4mR and Skud 18. The review of the Polish and foreign literature does not give a clear indication of the motives for participation in Paralympic sailing.

  3. Contact Issues on a Highly Flexible Frame for a Satellite Drag Sail

    DEFF Research Database (Denmark)

    Nikolajsen, Jan Ánike; Lauridsen, Peter Riddersholm; Kristensen, Anders Schmidt

    2017-01-01

    This processes the highly flexible frame for a drag sail in FEA with contacts and compared with experiments to get a better understanding of how well ANSYS can describe highly non-linear systems.......This processes the highly flexible frame for a drag sail in FEA with contacts and compared with experiments to get a better understanding of how well ANSYS can describe highly non-linear systems....

  4. The research on wing sail of a land-yacht robot

    Directory of Open Access Journals (Sweden)

    Shaorong Xie

    2015-12-01

    Full Text Available A wind-driven land-yacht robot which will be applied in polar expedition is presented in this article. As the main power of robot is provided by wing sail, improving the efficiency of wing sail is the key for its motion. Wing sail is composed of airfoil, so airfoil theory is researched first, and then several airfoils and their aerodynamic performance are compared, and a high-efficiency airfoil is selected. After that, overturning torque and start wind speed of robot are analyzed to determine the size of the wing sail. At last, the wing sail is manufactured and checked, and it is tested by start wind speed experiments, running speed experiments, steering motion, and obstacle avoidance experiments. The minimum start wind speed is 6 m/s. When wind speed is 10.3 m/s and angle of attack is 90°, running velocity of robot is 1.285 m/s. A land-yacht robot can run steering motion well and avoid obstacle to the target. The result shows that wing sail satisfies the motion requirement of land-yacht robot.

  5. Coupled attitude-orbit dynamics and control for an electric sail in a heliocentric transfer mission.

    Directory of Open Access Journals (Sweden)

    Mingying Huo

    Full Text Available The paper discusses the coupled attitude-orbit dynamics and control of an electric-sail-based spacecraft in a heliocentric transfer mission. The mathematical model characterizing the propulsive thrust is first described as a function of the orbital radius and the sail angle. Since the solar wind dynamic pressure acceleration is induced by the sail attitude, the orbital and attitude dynamics of electric sails are coupled, and are discussed together. Based on the coupled equations, the flight control is investigated, wherein the orbital control is studied in an optimal framework via a hybrid optimization method and the attitude controller is designed based on feedback linearization control. To verify the effectiveness of the proposed control strategy, a transfer problem from Earth to Mars is considered. The numerical results show that the proposed strategy can control the coupled system very well, and a small control torque can control both the attitude and orbit. The study in this paper will contribute to the theory study and application of electric sail.

  6. Coupled attitude-orbit dynamics and control for an electric sail in a heliocentric transfer mission.

    Science.gov (United States)

    Huo, Mingying; Zhao, Jun; Xie, Shaobiao; Qi, Naiming

    2015-01-01

    The paper discusses the coupled attitude-orbit dynamics and control of an electric-sail-based spacecraft in a heliocentric transfer mission. The mathematical model characterizing the propulsive thrust is first described as a function of the orbital radius and the sail angle. Since the solar wind dynamic pressure acceleration is induced by the sail attitude, the orbital and attitude dynamics of electric sails are coupled, and are discussed together. Based on the coupled equations, the flight control is investigated, wherein the orbital control is studied in an optimal framework via a hybrid optimization method and the attitude controller is designed based on feedback linearization control. To verify the effectiveness of the proposed control strategy, a transfer problem from Earth to Mars is considered. The numerical results show that the proposed strategy can control the coupled system very well, and a small control torque can control both the attitude and orbit. The study in this paper will contribute to the theory study and application of electric sail.

  7. The Coupled Orbit-Attitude Dynamics and Control of Electric Sail in Displaced Solar Orbits

    Directory of Open Access Journals (Sweden)

    Mingying Huo

    2017-01-01

    Full Text Available Displaced solar orbits for spacecraft propelled by electric sails are investigated. Since the propulsive thrust is induced by the sail attitude, the orbital and attitude dynamics of electric-sail-based spacecraft are coupled and required to be investigated together. However, the coupled dynamics and control of electric sails have not been discussed in most published literatures. In this paper, the equilibrium point of the coupled dynamical system in displaced orbit is obtained, and its stability is analyzed through a linearization. The results of stability analysis show that only some of the orbits are marginally stable. For unstable displaced orbits, linear quadratic regulator is employed to control the coupled attitude-orbit system. Numerical simulations show that the proposed strategy can control the coupled system and a small torque can stabilize both the attitude and orbit. In order to generate the control force and torque, the voltage distribution problem is studied in an optimal framework. The numerical results show that the control force and torque of electric sail can be realized by adjusting the voltage distribution of charged tethers.

  8. Design and Applications of Solar Sail Periodic Orbits in the Non-Autonomous Earth-Moon System

    NARCIS (Netherlands)

    Heiligers, M.J.; Macdonald, Malcolm; Parker, Jeffrey S.; Turner, J.D.; Wawrzyniak, G.G.; Cerven, W.T.; Majji, M.

    2015-01-01

    Solar sailing has great potential for a range of high-energy and long duration mis-sions in the Sun-Earth system. This paper extends this potential to the non-autonomous Earth-Moon system through the use of a differential correction scheme, and by selecting suitable in-plane and out-of-plane sail

  9. Momentum Management for the NASA Near Earth Asteroid Scout Solar Sail Mission

    Science.gov (United States)

    Heaton, Andrew; Diedrich, Benjamin L.; Orphee, Juan; Stiltner, Brandon; Becker, Christopher

    2017-01-01

    The Momentum Management (MM) system is described for the NASA Near Earth Asteroid Scout (NEA Scout) cubesat solar sail mission. Unlike many solar sail mission proposals that used solar torque as the primary or only attitude control system, NEA Scout uses small reaction wheels (RW) and a reaction control system (RCS) with cold gas thrusters, as described in the abstract "Solar Sail Attitude Control System for Near Earth Asteroid Scout Cubesat Mission." The reaction wheels allow fine pointing and higher rates with low mass actuators to meet the science, communication, and trajectory guidance requirements. The MM system keeps the speed of the wheels within their operating margins using a combination of solar torque and the RCS.

  10. Sustained Manned Mars Presence Enabled by E-sail Technology and Asteroid Water Mining

    Science.gov (United States)

    Janhunen, Pekka; Merikallio, Sini; Toivanen, Petri; Envall, M. Jouni

    The Electric Solar Wind Sail (E-sail) can produce 0.5-1 N of inexhaustible and controllable propellantless thrust [1]. The E-sail is based on electrostatic Coulomb interaction between charged thin tethers and solar wind ions. It was invented in 2006, was developed to TRL 4-5 in 2011-2013 with ESAIL FP7 project (http://www.electric-sailing.fi/fp7) and a CubeSat small-scale flight test is in course (ESTCube-1). The E-sail provides a flexible and efficient way of moving 0-2 tonne sized cargo payloads in the solar system without consuming propellant. Given the E-sail, one could use it to make manned exploration of the solar system more affordable by combining it with asteroid water mining. One first sends a miner spacecraft to an asteroid or asteroids, either by E-sail or traditional means. Many asteroids are known to contain water and liberating it only requires heating the material one piece at a time in a leak tight container. About 2 tonne miner can produce 50 tonnes of water per year which is sufficient to sustain continuous manned traffic between Earth and Mars. If the ice-bearing asteroid resides roughly at Mars distance, it takes 3 years for a 0.7 N E-sailer to transport a 10 tonne water/ice payload to Mars orbit or Earth C3 orbit. Thus one needs a fleet of 15 E-sail transport spacecraft plus replacements to ferry 50 tonnes of water yearly to Earth C3 (1/3) and Mars orbit (2/3). The mass of one transporter is 300 kg [2]. One needs to launch max 1.5 tonne mass of new E-sail transporters per year and in practice much less since it is simple to reuse them. This infrastructure is enough to supply 17 tonnes of water yearly at Earth C3 and 33 tonnes in Mars orbit. Orbital water can be used by manned exploration in three ways: (1) for potable water and for making oxygen, (2) for radiation shielding, (3) for LH2/LOX propellant. Up to 75 % of the wet mass of the manned module could be water (50 % propellant and 25 % radiation shield water). On top of this the total mass

  11. On-orbit verification of fuel-free attitude control system for spinning solar sail utilizing solar radiation pressure

    Science.gov (United States)

    Funase, Ryu; Shirasawa, Yoji; Mimasu, Yuya; Mori, Osamu; Tsuda, Yuichi; Saiki, Takanao; Kawaguchi, Jun'ichiro

    2011-12-01

    This paper introduces a new attitude control system for a solar sail, which leverages solar radiation pressure. This novel system achieves completely fuel-free and oscillation-free attitude control of a flexible spinning solar sail. This system consists of thin-film-type devices that electrically control their optical parameters such as reflectivity to generate an imbalance in the solar radiation pressure applied to the edge of the sail. By using these devices, minute and continuous control torque can be applied to the sail to realize very stable and fuel-free attitude control of the large and flexible membrane. The control system was implemented as an optional attitude control system for small solar power sail demonstrator named IKAROS (Interplanetary Kite-craft Accelerated by Radiation Of the Sun). In-orbit attitude control experiments were conducted, and the performance of the controller was successfully verified in comparison with the ground-based analytical performance estimation.

  12. Becoming a Coach in Developmental Adaptive Sailing: A Lifelong Learning Perspective.

    Science.gov (United States)

    Duarte, Tiago; Culver, Diane M

    2014-10-02

    Life-story methodology and innovative methods were used to explore the process of becoming a developmental adaptive sailing coach. Jarvis's (2009) lifelong learning theory framed the thematic analysis. The findings revealed that the coach, Jenny, was exposed from a young age to collaborative environments. Social interactions with others such as mentors, colleagues, and athletes made major contributions to her coaching knowledge. As Jenny was exposed to a mixture of challenges and learning situations, she advanced from recreational para-swimming instructor to developmental adaptive sailing coach. The conclusions inform future research in disability sport coaching, coach education, and applied sport psychology.

  13. Solar Sailing Kinetic Energy Interceptor (KEI) Mission for Impacting/Deflecting Near-Earth Asteroids

    Science.gov (United States)

    Wie, Bong

    2005-01-01

    A solar sailing mission architecture, which requires a t least ten 160-m, 300-kg solar sail spacecraft with a characteristic acceleration of 0.5 mm/sqs, is proposed as a realistic near- term option for mitigating the threat posed by near-Earth asteroids (NEAs). Its mission feasibility is demonstrated for a fictional asteroid mitigation problem created by AIAA. This problem assumes that a 200-m asteroid, designated 2004WR, was detected on July 4, 2004, and that the expected impact will occur on January 14, 2015. The solar sailing phase of the proposed mission for the AIAA asteroid mitigation problem is comprised of the initial cruise phase from 1 AU t o 0.25 AU (1.5 years), the cranking orbit phase (3.5 years), and the retrograde orbit phase (1 year) prior to impacting the target asteroid at its perihelion (0.75 AU from the sun) on January 1, 2012. The proposed mission will require at least ten kinetic energy interceptor (KEI) solar sail spacecraft. Each KEI sailcraft consists of a 160- m, 150-kg solar sail and a 150-kg microsatellite impactor. The impactor is to be separated from a large solar sail prior to impacting the 200-m target asteroid at its perihelion. Each 150-kg microsatellite impactor, with a relative impact velocity of at least 70 km/s, will cause a conservatively estimated AV of 0.3 cm/s in the trajectory of the 200-m target asteroid, due largely to the impulsive effect of material ejected from the newly-formed crater. The deflection caused by a single impactor will increase the Earth-miss-distance by 0.45Re (where Re denotes the Earth radius of 6,378 km). Therefore, at least ten KEI sailcraft will be required for consecutive impacts, but probably without causing fragmentation, to increase the total Earth-miss-distance by 4.5Re. This miss-distance increase of 29,000 km is outside of a typical uncertainty/error of about 10,000 km in predicting the Earth-miss- distance. A conventional Delta I1 2925 launch vehicle is capable of injecting at least two KEI

  14. Becoming a Coach in Developmental Adaptive Sailing: A Lifelong Learning Perspective

    Science.gov (United States)

    Duarte, Tiago; Culver, Diane M.

    2014-01-01

    Life-story methodology and innovative methods were used to explore the process of becoming a developmental adaptive sailing coach. Jarvis's (2009) lifelong learning theory framed the thematic analysis. The findings revealed that the coach, Jenny, was exposed from a young age to collaborative environments. Social interactions with others such as mentors, colleagues, and athletes made major contributions to her coaching knowledge. As Jenny was exposed to a mixture of challenges and learning situations, she advanced from recreational para-swimming instructor to developmental adaptive sailing coach. The conclusions inform future research in disability sport coaching, coach education, and applied sport psychology. PMID:25210408

  15. Thrust calculation of electric solar wind sail by particle-in-cell simulation

    Energy Technology Data Exchange (ETDEWEB)

    Hoshi, Kento [Kyoto Univ. (Japan). Dept. of Electrical Engineering; Kojima, Hirotsugu; Yamakawa, Hiroshi [Kyoto Univ. (Japan). Research Inst. for Sustainable Humanosphere; Muranaka, Takanobu [Chukyo Univ., Nagoya (Japan). Dept. of Electrical Engineering

    2016-07-01

    In this study, thrust characteristics of an electric solar wind sail were numerically evaluated using full threedimensional particle-in-cell (PIC) simulation. The thrust obtained from the PIC simulation was lower than the thrust estimations obtained in previous studies. The PIC simulation indicated that ambient electrons strongly shield the electrostatic potential of the tether of the sail, and the strong shield effect causes a greater thrust reduction than has been obtained in previous studies. Additionally, previous expressions of the thrust estimation were modified by using the shielded potential structure derived from the present simulation results. The modified thrust estimation agreed very well with the thrust obtained from the PIC simulation.

  16. How Stable is a Light Sail Riding on a Laser Beam?

    Science.gov (United States)

    Kohler, Susanna

    2017-03-01

    The Breakthrough Starshot Initiative made headlines last year when the plan was first announced to send tiny spacecraft to our nearest stellar neighbors. But just how feasible is this initiative? A new study looks at just one aspect of this plan: whether we can propel the spacecraft successfully.Propelling a FleetThe Alpha Centauri star system, which consists of Alpha (left) and Beta (right) Centauri as well as Proxima Centauri (circled). [Skatebiker]The goal behind the Breakthrough Starshot Initiative is to build a fleet of tiny, gram-scale spacecraft to travel to the Alpha Centauri star system a systemin whicha planet was recently discovered around Proxima Centauri, the star nearest to us.To propel the spacecraft, the team plans to attach a reflective sail to each one. When a high-power laser beam is pointed at that sail from Earth, the impulse of the photons bouncing off the sail can acceleratethe lightweight spacecraft to a decent fraction of the speed of light, allowing it to reach the Alpha Centauri system within decades.Among the many potential engineering challenges forsuch a mission, one interesting one is examined in a recent study by Zachary Manchester and Avi Loeb of Harvard University: how do wekeep the spacecrafts light sail centered on the laser beam long enough to accelerate it?Beam profile (left) and corresponding potential function (right) for a laser beam made up of four Gaussians. With this configuration, the potential well pushes the spacecraft back to the center if it drifts toward the edges of the well. [Manchester Loeb 2017]The Search for StabilityManchester and Loeb arguethat any slight perturbations to the light sails position relative to the laser beam in the form of random disturbances, misalignments, or manufacturing imperfections could cause it to slide off the beam, preventing it from continuing toaccelerate. Ideally, the project would use a sail that could be passively stable: the sail wants to stay centered on the beam, rather than

  17. Proximal Blade Twist Feedback Control for Heliogyro Solar Sails

    Science.gov (United States)

    Smith, Sarah Mitchell

    A heliogyro spacecraft is a specific type of solar sail that generates thrust from the reflection of solar photons. It consists of multiple long (200 to 600 meters), thin blades, similar to a helicopter. The heliogyro's blades remain in tension by spinning around the central hub of the spacecraft. The individual blades are pitched collectively or cyclically to produce the desired maneuver profile. The propellant-free heliogyro is a long-duration sustainable spacecraft whose maneuverability allows it to attain previously inaccessible orbits for traditional spacecraft. The blades are constructed from thin Mylar sheets, approximately 2.5 ?m thick, which have very little inherent damping making it necessary to include some other way of attenuating blade vibration caused by maneuvering. The most common approach is to incorporate damping through the root pitch actuator. However, due to the small root pitch control torques required, on the order of 2 ?Nm, compared to the large friction torques associated with a root pitch actuator, it is challenging to design a root control system that takes friction into account and can still add damping to the blade. The purpose of this research is to address the limitations of current control designs for a heliogyro spacecraft and to develop a physically realizable root pitch controller that effectively damps the torsional structural modes of a single heliogyro blade. Classical control theory in conjunction with impedance control techniques are used to design a position-source root pitch controller to dominate friction with high gains, wrapped with an outer loop that adds damping to the blade by sensing differential twist outboard of the blade root. First, modal parameter characterization experiments were performed on a small-scale heliogyro blade in a high vacuum chamber to determine a damping constant to be used in the membrane ladder finite element model of the blade. The experimental damping ratio of the lowest frequency torsional

  18. Making and Executing Decisions for Safe and Independent Living (MED-SAIL): development and validation of a brief screening tool.

    Science.gov (United States)

    Mills, Whitney L; Regev, Tziona; Kunik, Mark E; Wilson, Nancy L; Moye, Jennifer; McCullough, Laurence B; Naik, Aanand D

    2014-03-01

    Older adults prefer to remain in their own homes for as long as possible. The purpose of this article is to describe the development and preliminary validation of Making and Executing Decisions for Safe and Independent Living (MED-SAIL), a brief screening tool for capacity to live safely and independently in the community. Prospective preliminary validation study. Outpatient geriatrics clinic located in a community-based hospital. Forty-nine community-dwelling older adults referred to the clinic for a comprehensive capacity assessment. We examined internal consistency, criterion-based validity, concurrent validity, and accuracy of classification for MED-SAIL. The items included in MED-SAIL demonstrated internal consistency (5 items; α = 0.85). MED-SAIL was significantly correlated with the Independent Living Scales (r = 0.573, p ≤0.001) and instrumental activities of daily living (r = 0.440, p ≤0.01). The Mann-Whitney U test revealed significant differences between the no capacity and partial/full capacity classifications on MED-SAIL (U(48) = 60.5, Z = -0.38, p MED-SAIL as a brief screening tool to identify older adults with impaired capacity for remaining safe and independent in their current living environment. MED-SAIL is useful tool for health and social service providers in the community for the purpose of referral for definitive capacity evaluation. Published by Elsevier Inc.

  19. TRL Assessment of Solar Sail Technology Development Following the 20-Meter System Ground Demonstrator Hardware Testing

    Science.gov (United States)

    Young, Roy M.; Adams, Charles L.

    2010-01-01

    The NASA In-Space Propulsion Technology (ISPT) Projects Office sponsored two separate, independent solar sail system design and development demonstration activities during 2002-2005. ATK Space Systems of Goleta, CA was the prime contractor for one development team and L' Garde, Inc. of Tustin, CA was the prime contractor for the other development team. The goal of these activities was to advance the technology readiness level (TRL) of solar sail propulsion from 3 towards 6 by the year 2006. Component and subsystem fabrication and testing were completed successfully, including the ground deployment of 10-meter and 20-meter demonstration hardware systems under vacuum conditions. The deployment and structural testing of the 20-meter solar sail systems was conducted in the 30 meter diameter Space Power Facility thermal-vacuum chamber at NASA Glenn Plum Brook in April though August, 2005. This paper will present the results of the TRL assessment following the solar sail technology development activities associated with the design, development, analysis and testing of the 20-meter system ground demonstrators.

  20. Photogrammetry and Videogrammetry Methods for Solar Sails and Other Gossamer Structures

    Science.gov (United States)

    Black, Jonathan T.; Pappa, Richard S.

    2004-01-01

    Ultra-lightweight and inflatable gossamer space structures are designed to be tightly packaged for launch, then deploy or inflate once in space. These properties will allow for in-space construction of very large structures 10 to 1000 meters in size such as solar sails, inflatable antennae, and space solar power stations using a single launch. Solar sails are of particular interest because of their potential for propellantless propulsion. Gossamer structures do, however, have significant complications. Their low mass and high flexibility make them very difficult to test on the ground. The added mass and stiffness of attached measurement devices can significantly alter the static and dynamic properties of the structure. This complication necessitates an alternative approach for characterization. This paper discusses the development and application of photogrammetry and videogrammetry methods for the static and dynamic characterization of gossamer structures, as four specific solar sail applications demonstrate. The applications prove that high-resolution, full-field, non-contact static measurements of solar sails using dot projection photogrammetry are possible as well as full-field, noncontact, dynamic characterization using dot projection videogrammetry.

  1. On two speed optimization problems for ships that sail in and out of emission control areas

    DEFF Research Database (Denmark)

    Fagerholt, Kjetil; Psaraftis, Harilaos N.

    2015-01-01

    This paper deals with two speed optimization problems for ships that sail in and out of Emission Control Areas (ECAs) with strict limits on sulfur emissions. For ships crossing in and out of ECAs, such as deep-sea vessels, one of the common options for complying with these limits is to burn heavy...

  2. Formation flying for electric sails in displaced orbits. Part II: Distributed coordinated control

    Science.gov (United States)

    Wang, Wei; Mengali, Giovanni; Quarta, Alessandro A.; Yuan, Jianping

    2017-09-01

    We analyze a cooperative control framework for electric sail formation flying around a heliocentric displaced orbit, aiming at observing the polar region of a celestial body. The chief spacecraft is assumed to move along an elliptic displaced orbit, while each deputy spacecraft adjusts its thrust vector (that is, both its sail attitude and characteristic acceleration) in order to track a prescribed relative trajectory. The relative motion of the electric sail formation system is formulated in the chief rotating frame, where the control inputs of each deputy are the relative sail attitude angles and the relative lightness number with respect to those of the chief. The information exchange among the spacecraft, characterized by the communication topology, is represented by a weighted graph. Two typical cases, according to whether the communication graph is directed or undirected, are discussed. For each case, a distributed coordinated control law is designed in such a way that each deputy not only tracks the chief state, but also makes full use of information from its neighbors, thus increasing the redundancy and robustness of the formation system in case of failure among the communication links. Illustrative examples show the effectiveness of the proposed approach.

  3. The Response of Old Technology Incumbents to Technological Competition - Does the Sailing Ship Effect Exist?

    DEFF Research Database (Denmark)

    Howells, John

    This article investigates whether firms react to a radical technological substitution threat by a deliberate acceleration of innovation in their existing technology - the 'sailing ship effect'. It has been argued that the effect is both significant and widespread and warrants a reexamination of our...

  4. Effect of Teaching Races for Understanding in Youth Sailing on Performance, Knowledge, and Adherence.

    Science.gov (United States)

    Morales-Belando, María Trinidad; Arias-Estero, José L

    2017-12-01

    The purpose of this study was to know whether an intervention using an adaptation of the teaching games for understanding approach (named teaching races for understanding [TRfU]) led participants to improve skill execution, decision making, race performance, race involvement, race knowledge, enjoyment, intention to continue practicing sailing, and perceived competence. Participants were 67 children from a randomly selected sailing school (Mage = 9.32 years, SD = 2.60 years) and 2 coaches. We designed and validated the TRfU lessons, and 1 coach was trained in the approach. The TRfU group participated in 11 lessons. This study followed a mixed-methods data approach. Quantitative data were evaluated using a quasiexperimental pretest-posttest design with a control group. The intervention consisted of teaching sailing using the TRfU approach. Children and coaches' perceptions were evaluated through an interview on completion of the study. Data were collected using an adaptation of the Game Performance Assessment Instrument, a knowledge questionnaire, 2 psychological scales, and interviews with children and coaches. The TRfU group showed statistically significant improvements in skill execution, decision making, and race performance compared with the control group, as well as significant improvements in race involvement, race knowledge, and enjoyment (ES = 0.64-2.63). Teaching races for understanding can be used in sailing to improve students' capacity to reflect and connect theoretical knowledge with their motor performance in the race.

  5. Development of Solar Sail Propulsion for Inner Solar System NASA Science Missions

    Science.gov (United States)

    Montgomery, Edward E., IV; Johnson, Les

    2004-01-01

    This paper examines recent assessments of the technology challenges facing solar sails, identifies the systems and technologies needing development, and the approach employed by NASA's In-Space Propulsion program in NASA to achieve near-term products that move this important technology from low technology readiness level toward the goal of application to science missions in near-Earth space and beyond.

  6. HORIZONTAL AXIS MARINE CURRENT TURBINE DESIGN FOR WIND-ELECTRIC HYBRID SAILING BOAT

    Directory of Open Access Journals (Sweden)

    Serkan Ekinci

    2017-01-01

    Full Text Available In recent decades, the number of theoretical studies and applications on electric power production from renewable sources such as wind, solar, sea and tidal flows, has been increasing rapidly. Marine Current Turbines (MCTs, among the power turbines, produce power from alternating flows and are a means of power production even at lower flow rates in oceans and seas. In this study, while maintaining functional requirements, an initial and detailed design (mechanic and hydrodynamic, of an MCT fixed on a sailing boat and at sail which extracts power from the flow around the boat, is undertaken. In the design stages, for analysis and optimization of the marine turbine blade design, the Momentum Blade Element Method is utilized. The Horizontal Axis Marine Turbine (HAMT, determined by the initial and mechanical design, is illustrated with its components included. Computational fluid dynamics (CFD analyses, covering turbine pod geometry at required flow rates and turbine speeds are performed. These analyses are performed very close to real conditions, considering sailing with and without the turbine running (on and off states. The alternator is determined from the results, and the final design which meets the design requirements, is obtained. As a result, a user friendly and innovative turbine design for sail boats, offering more power and efficiency, which is longer lasting compared to solar and wind technologies, that also makes use of renewable sources, such as wind and/or solar, and in addition stores and uses accumulated energy when needed, is proposed.

  7. Simultaneous Optimization of Container Ship Sailing Speed and Container Routing with Transit Time Restrictions

    DEFF Research Database (Denmark)

    Karsten, Christian Vad; Røpke, Stefan; Pisinger, David

    We introduce a decision support tool for liner shipping companies to optimally determine the sailing speed and needed fleet for a global network. As a novelty we incorporate cargo routing decisions with tight transit time restrictions on each container such that we get a realistic picture...

  8. Novel Solar Sail Mission Concepts for High-Latitude Earth and Lunar Observation

    NARCIS (Netherlands)

    Heiligers, M.J.; Parker, Jeffrey S.; Macdonald, Malcolm

    2016-01-01

    This paper proposes the use of solar sail periodic orbits in the Earth-Moon system for ob-servation of the high-latitudes of the Earth and Moon. At the Earth, the high-latitudes will be crucial in answering questions concerning global climate change, monitoring space weather events and ensuring

  9. Steering a Course towards Eudaimonia: The Effects of Sail Training on Well-Being and Character

    Science.gov (United States)

    Fletcher, Eric; Prince, Heather

    2017-01-01

    Sail training voyages have been shown to enhance self-constructs and inter-personal and intra-personal skills. It is suggested through this case-study approach with twelve 14 year-old crew participants that such an experience contributes towards well-being and character development in emerging adulthood. An audit of voyage-based experiences…

  10. PROSPECT and SAIL models: a review of use for vegetation characterization

    NARCIS (Netherlands)

    Jacquemond, S.; Verhoef, W.; Baret, F.; Bacour, C.; Zarco-Tejada, P.; Asner, G.P.; Francois, C.; Ustin, S.L.

    2009-01-01

    The combined PROSPECT leaf optical properties model and SAIL canopy bidirectional reflectance model, also referred to as PROSAIL, has been used for about sixteen years to study plant canopy spectral and directional reflectance in the solar domain. PROSAIL has also been used to develop new methods

  11. Hybrids of Solar Sail, Solar Electric, and Solar Thermal Propulsion for Solar-System Exploration

    Science.gov (United States)

    Wilcox, Brian H.

    2012-01-01

    Solar sails have long been known to be an attractive method of propulsion in the inner solar system if the areal density of the overall spacecraft (S/C) could be reduced to approx.10 g/sq m. It has also long been recognized that the figure (precise shape) of useful solar sails needs to be reasonably good, so that the reflected light goes mostly in the desired direction. If one could make large reflective surfaces with reasonable figure at an areal density of approx.10 g/sq m, then several other attractive options emerge. One is to use such sails as solar concentrators for solar-electric propulsion. Current flight solar arrays have a specific output of approx. 100W/kg at 1 Astronomical Unit (AU) from the sun, and near-term advances promise to significantly increase this figure. A S/C with an areal density of 10 g/sq m could accelerate up to 29 km/s per year as a solar sail at 1 AU. Using the same sail as a concentrator at 30 AU, the same spacecraft could have up to approx. 45 W of electric power per kg of total S/C mass available for electric propulsion (EP). With an EP system that is 50% power-efficient, exhausting 10% of the initial S/C mass per year as propellant, the exhaust velocity is approx. 119 km/s and the acceleration is approx. 12 km/s per year. This hybrid thus opens attractive options for missions to the outer solar system, including sample-return missions. If solar-thermal propulsion were perfected, it would offer an attractive intermediate between solar sailing in the inner solar system and solar electric propulsion for the outer solar system. In the example above, both the solar sail and solar electric systems don't have a specific impulse that is near-optimal for the mission. Solar thermal propulsion, with an exhaust velocity of the order of 10 km/s, is better matched to many solar system exploration missions. This paper derives the basic relationships between these three propulsion options and gives examples of missions that might be enabled by

  12. Study of a 30-M Boom For Solar Sail-Craft: Model Extendibility and Control Strategy

    Science.gov (United States)

    Keel, Leehyun

    2005-01-01

    Space travel propelled by solar sails is motivated by the fact that the momentum exchange that occurs when photons are reflected and/or absorbed by a large solar sail generates a small but constant acceleration. This acceleration can induce a constant thrust in very large sails that is sufficient to maintain a polar observing satellite in a constant position relative to the Sun or Earth. For long distance propulsion, square sails (with side length greater than 150 meters) can reach Jupiter in two years and Pluto in less than ten years. Converting such design concepts to real-world systems will require accurate analytical models and model parameters. This requires extensive structural dynamics tests. However, the low mass and high flexibility of large and light weight structures such as solar sails makes them unsuitable for ground testing. As a result, validating analytical models is an extremely difficult problem. On the other hand, a fundamental question can be asked. That is whether an analytical model that represents a small-scale version of a solar-sail boom can be extended to much larger versions of the same boom. To answer this question, we considered a long deployable boom that will be used to support the solar sails of the sail-craft. The length of fully deployed booms of the actual solar sail-craft will exceed 100 meters. However, the test-bed we used in our study is a 30 meter retractable boom at MSFC. We first develop analytical models based on Lagrange s equations and the standard Euler-Bernoulli beam. Then the response of the models will be compared with test data of the 30 meter boom at various deployed lengths. For this stage of study, our analysis was limited to experimental data obtained at 12ft and 18ft deployment lengths. The comparison results are positive but speculative. To observe properly validate the analytic model, experiments at longer deployment lengths, up to the full 30 meter, have been requested. We expect the study to answer the

  13. Performance quantification of heliogyro solar sails using structural, attitude, and orbital dynamics and control analysis

    Science.gov (United States)

    Guerrant, Daniel Vernon

    Solar sails enable or enhance exploration of a variety of destinations both within and without the solar system. The heliogyro solar sail architecture divides the sail into blades spun about a central hub and centrifugally stiffened. The resulting structural mass savings can often double acceleration verses kite-type square sails of the same mass. Pitching the blades collectively and cyclically, similar to a helicopter, creates attitude control moments and vectors thrust. The principal hurdle preventing heliogyros' implementation is the uncertainty in their dynamics. This thesis investigates attitude, orbital and structural control using a combination of analytical studies and simulations. Furthermore, it quantifies the heliogyro's ability to create attitude control moments, change the thrust direction, and stably actuate blade pitch. This provides engineers a toolbox from which to estimate the heliogyro's performance and perform trades during preliminary mission design. It is shown that heliogyros can create an attitude control moment in any direction from any orientation. While their large angular momentum limits attitude slewing to only a few degrees per hour, cyclic blade pitching can slew the thrust vector within a few minutes. This approach is only 13% less efficient than slewing a square sail during Earth escape, so it does not offset the overall acceleration benefits of heliogyros. Lastly, a root pitch motor should be able to settle torsional disturbances within a few rotations and achieve thrust performance comparable to that of flat blades. This work found no significant dynamic hurdles for heliogyros, and it provides key insight into their practical capabilities and limitations for future mission designers.

  14. Communicating LightSail: Embedded Reporting and Web Strategies for Citizen-Funded Space Missions

    Science.gov (United States)

    Hilverda, M.; Davis, J.

    2015-12-01

    The Planetary Society (TPS) is a non-profit space advocacy group with a stated mission to "empower the world's citizens to advance space science and exploration." In 2009, TPS began work on LightSail, a small, citizen-funded spacecraft to demonstrate solar sailing propulsion technology. The program included a test flight, completed in June 2015, with a primary mission slated for late 2016. TPS initiated a LightSail public engagement campaign to provide the public with transparent mission updates, and foster educational outreach. A credentialed science journalist was given unrestricted access to the team and data, and provided regular reports without editorial oversight. An accompanying website, sail.planetary.org, provided project updates, multimedia, and real-time spacecraft data during the mission. Design approaches included a clean layout with text optimized for easy reading, balanced by strong visual elements to enhance reader comprehension and interest. A dedicated "Mission Control" page featured social media feeds, links to most recent articles, and a ground track showing the spacecraft's position, including overflight predictions based on user location. A responsive, cross-platform design allowed easy access across a broad range of devices. Efficient web server performance was prioritized by implementing a static content management system (CMS). Despite two spacecraft contingencies, the test mission successfully completed its primary objective of solar sail deployment. Qualitative feedback on the transparent, embedded reporting style was positive, and website metrics showed high user retention times. The website also grew awareness and support for the primary 2016 mission, driving traffic to a Kickstarter campaign that raised $1.24 million. Websites constantly evolve, and changes for the primary mission will include a new CMS to better support multiple authors and a custom dashboard to display real-time spacecraft sensor data.

  15. Project Dragonfly: A feasibility study of interstellar travel using laser-powered light sail propulsion

    Science.gov (United States)

    Perakis, Nikolaos; Schrenk, Lukas E.; Gutsmiedl, Johannes; Koop, Artur; Losekamm, Martin J.

    2016-12-01

    Light sail-based propulsion systems are a candidate technology for interplanetary and interstellar missions due to their flexibility and the fact that no fuel has to be carried along. In 2014, the Initiative for Interstellar Studies (i4is) hosted the Project Dragonfly Design Competition, which aimed at assessing the feasibility of sending an interstellar probe propelled by a laser-powered light sail to another star system. We analyzed and designed a mission to the Alpha Centauri system, with the objective to carry out science operations at the destination. Based on a comprehensive evaluation of currently available technologies and possible locations, we selected a lunar architecture for the laser system. It combines the advantages of surface- and space-based systems, as it requires no station keeping and suffers no atmospheric losses. We chose a graphene-based sandwich material for the light sail because of its low density. Deceleration of the spacecraft sufficient for science operations at the target system is achieved using both magnetic and electric sails. Applying these assumptions in a simulation leads to the conclusion that 250 kg of scientific payload can be sent to Alpha Centauri within the Project Dragonfly Design Competition's constraints of 100 year travel duration and 100 GW laser beam power. This is only sufficient to fulfill parts of the identified scientific objectives, and therefore renders the usefulness of such a mission questionable. A better sail material or higher laser power would improve the acceleration behavior, an increase in the mission time would allow for larger spacecraft masses.

  16. Three-Axis Attitude Control of Solar Sails Utilising Reflectivity Control Devices

    Science.gov (United States)

    Theodorou, Theodoros

    Solar sails are spacecraft that utilise the Solar Radiation Pressure, the force generated by impinging photons, to propel themselves. Conventional actuators are not suitable for controlling the attitude of solar sails therefore specific attitude control methods have been devised to tackle this. One of these methods is to change the centre of pressure with respect to the center of mass thus creating a torque. Reflectivity Control Devices (RCDs) have been proposed and successfully used to change the centre of pressure. Current methods that utilise RCDs have control authority over two axis only with no ability to control the torque about the normal of the sail surface. This thesis extends the state of the art and demonstrates 3-axis control by generating arbitrary torque vectors within a convex polyhedron. Two different RCD materials are considered, transmission and diffusion technologies both compatible with the proposed concept. A number of metrics have been developed which facilitate the comparison of different sail configurations. One of these metics is the sun map which is a graphic representation of the sun angles for which control authority is maintained. An iterative design process is presented which makes use of the metrics developed and aids in the design of a sail which meets the mission requirements and constraints. Moreover, the effects of different parameters on the performance of the proposed control concept are discussed. For example it is shown that by alternating the angle between the edge and middle RCDs the control authority increases. The concept's scalability has been investigated and a hybrid control scheme has been devised which makes use of both RCDs and reaction wheels. The RCDs are complemented by the reaction wheels to achieve higher slew rates while in turn the RCDs desaturate the reaction wheels. Finally, a number of simulations are conducted to verify the validity of the proposed concept.

  17. In-Vacuum Photogrammetry of a Ten-Meter Square Solar Sail

    Science.gov (United States)

    Pappa, Richard S.; Jones, Thomas W.; Lunsford, Charles B.; Meyer, Christopher G.

    2006-01-01

    Solar sailing is a promising, future in-space propulsion method that uses the small force of reflecting sunlight to accelerate a large, reflective membrane without expendable propellants. One of two solar sail configurations under development by NASA is a striped net approach by L'Garde, Inc. This design uses four inflatably deployed, lightweight booms supporting a network of thin strings onto which four quadrants of ultrathin aluminized membranes are attached. The NASA Langley Research Center (LaRC) provided both experimental and analytical support to L'Garde for validating the structural characteristics of this unique, ultralightweight spacecraft concept. One of LaRC's responsibilities was to develop and apply photogrammetric methods to measure sail shape. The deployed shape provides important information for validating the accuracy of finite-element modeling techniques. Photogrammetry is the science and art of calculating 3D coordinates of targets or other distinguishing features on structures using images. A minimum of two camera views of each target is required for 3D determination, but having four or more camera views is preferable for improved reliability and accuracy. Using retroreflective circular targets typically provides the highest measurement accuracy and automation. References 3 and 4 provide details of photogrammetry technology, and reference 5 discusses previous experiences with photogrammetry for measuring gossamer spacecraft structures such as solar sails. This paper discusses the experimental techniques used to measure a L Garde 10-m solar sail test in vacuum with photogrammetry. The test was conducted at the NASA-Glenn Space Power Facility (SPF) located at Plum Brook Station in Sandusky, Ohio. The SPF is the largest vacuum chamber in the United States, measuring 30 m in diameter by 37 m in height. High vacuum levels (10(exp -6) torr) can be maintained inside the chamber, and cold environments (-195 C) are possible using variable

  18. Tribute to Dr Jacques Rogge: muscle activity and fatigue during hiking in Olympic dinghy sailing.

    Science.gov (United States)

    Bourgois, Jan G; Dumortier, Jasmien; Callewaert, Margot; Celie, Bert; Capelli, Carlo; Sjøgaard, Gisela; De Clercq, Dirk; Boone, Jan

    2017-06-01

    'A tribute to Dr J. Rogge' aims to systematically review muscle activity and muscle fatigue during sustained submaximal quasi-isometric knee extension exercise (hiking) related to Olympic dinghy sailing as a tribute to Dr Rogge's merits in the world of sports. Dr Jacques Rogge is not only the former President of the International Olympic Committee, he was also an orthopaedic surgeon and a keen sailor, competing at three Olympic Games. In 1972, in fulfilment of the requirements for the degree of Master in Sports Medicine, he was the first who studied a sailors' muscle activity by means of invasive needle electromyography (EMG) during a specific sailing technique (hiking) on a self-constructed sailing ergometer. Hiking is a bilateral and multi-joint submaximal quasi-isometric movement which dinghy sailors use to optimize boat speed and to prevent the boat from capsizing. Large stresses are generated in the anterior muscles that cross the knee and hip joint, mainly employing the quadriceps at an intensity of 30-40% maximal voluntary contraction (MVC), sometimes exceeding 100% MVC. Better sailing level is partially determined by a lower rate of neuromuscular fatigue during hiking and for ≈60% predicted by a higher maximal isometric quadriceps strength. Although useful in exercise testing, prediction of hiking endurance capacity based on the changes in surface EMG in thigh and trunk muscles during a hiking maintenance task is not reliable. This could probably be explained by the varying exercise intensity and joint angles, and the great number of muscles and joints involved in hiking. Highlights Dr Jacques Rogge, former president of the International Olympic Committee and Olympic Finn sailor, was the first to study muscle activity during sailing using invasive needle EMG to obtain his Master degree in Sports Medicine at the Ghent University. Hiking is a critical bilateral and multi-joint movement during dinghy racing, accounting for >60% of the total upwind leg time

  19. Photogrammetry and Videogrammetry Methods Development for Solar Sail Structures. Masters Thesis awarded by George Washington Univ.

    Science.gov (United States)

    Pappa, Richard S. (Technical Monitor); Black, Jonathan T.

    2003-01-01

    This report discusses the development and application of metrology methods called photogrammetry and videogrammetry that make accurate measurements from photographs. These methods have been adapted for the static and dynamic characterization of gossamer structures, as four specific solar sail applications demonstrate. The applications prove that high-resolution, full-field, non-contact static measurements of solar sails using dot projection photogrammetry are possible as well as full-field, non-contact, dynamic characterization using dot projection videogrammetry. The accuracy of the measurement of the resonant frequencies and operating deflection shapes that were extracted surpassed expectations. While other non-contact measurement methods exist, they are not full-field and require significantly more time to take data.

  20. Advanced Deployable Shell-Based Composite Booms for Small Satellite Structural Applications Including Solar Sails

    Science.gov (United States)

    Fernandez, Juan M.

    2017-01-01

    State of the art deployable structures are mainly being designed for medium to large size satellites. The lack of reliable deployable structural systems for low cost, small volume, rideshare-class spacecraft severely constrains the potential for using small satellite platforms for affordable deep space science and exploration precursor missions that could be realized with solar sails. There is thus a need for reliable, lightweight, high packaging efficiency deployable booms that can serve as the supporting structure for a wide range of small satellite systems including solar sails for propulsion. The National Air and Space Administration (NASA) is currently investing in the development of a new class of advanced deployable shell-based composite booms to support future deep space small satellite missions using solar sails. The concepts are being designed to: meet the unique requirements of small satellites, maximize ground testability, permit the use of low-cost manufacturing processes that will benefit scalability, be scalable for use as elements of hierarchical structures (e.g. trusses), allow long duration storage, have high deployment reliability, and have controlled deployment behavior and predictable deployed dynamics. This paper will present the various rollable boom concepts that are being developed for 5-20 m class size deployable structures that include solar sails with the so-called High Strain Composites (HSC) materials. The deployable composite booms to be presented are being developed to expand the portfolio of available rollable booms for small satellites and maximize their length for a given packaged volume. Given that solar sails are a great example of volume and mass optimization, the booms were designed to comply with nominal solar sail system requirements for 6U CubeSats, which are a good compromise between those of smaller form factors (1U, 2U and 3U CubeSats) and larger ones (12 U and 27 U future CubeSats, and ESPA-class microsatellites). Solar

  1. Formation flying for electric sails in displaced orbits. Part I: Geometrical analysis

    Science.gov (United States)

    Wang, Wei; Mengali, Giovanni; Quarta, Alessandro A.; Yuan, Jianping

    2017-09-01

    We present a geometrical methodology for analyzing the formation flying of electric solar wind sail based spacecraft that operate in heliocentric, elliptic, displaced orbits. The spacecraft orbit is maintained by adjusting its propulsive acceleration modulus, whose value is estimated using a thrust model that takes into account a variation of the propulsive performance with the sail attitude. The properties of the relative motion of the spacecraft are studied in detail and a geometrical solution is obtained in terms of relative displaced orbital elements, assumed to be small quantities. In particular, for the small eccentricity case (i.e. for a near-circular displaced orbit), the bounds characterized by the extreme values of relative distances are analytically calculated, thus providing an useful mathematical tool for preliminary design of the spacecraft formation structure.

  2. Sailing Vessel Routing Considering Safety Zone and Penalty Time for Altering Course

    Directory of Open Access Journals (Sweden)

    Marcin Zyczkowski

    2017-06-01

    Full Text Available In this paper we introduce new model for simulation sea vessel routing. Besides a vessel types (polar diagram and weather forecast, travel security and the number of maneuvers are considered. Based on these data both the minimal travelling costs and the minimal processing time are found for different vessels and different routes. To test our model the applications SailingAssistance wad improved. The obtained results shows that we can obtain quite acceptable results.

  3. Approximate Method of Calculating Forces on Rudder During Ship Sailing on a Shipping Route

    Directory of Open Access Journals (Sweden)

    K. Zelazny

    2014-09-01

    Full Text Available Service speed of a ship in real weather conditions is a basic design parameter. Forecasting of this speed at preliminary design stage is made difficult by the lack of simple but at the same accurate models of forces acting upon a ship sailing on a preset shipping route. The article presents a model for calculating forces and moment on plane rudder, useful for forecasting of ship service speed at preliminary stages of ship design.

  4. PSYCHOLOGICAL PECULIARITIES OF TEACHING FUTURE NAVIGATORS READING ENGLISH AUTHENTIC SAILING DIRECTIONS

    Directory of Open Access Journals (Sweden)

    Наталія Приміна

    2014-07-01

    Full Text Available In the given article the psychological peculiarities of teaching future navigators reading English professional authentic documentation have been analyzed. The psychological foundations of understanding printed information in general and foreign information particularly have been disclosed. The processes of textual information perception and visual material perception comprehension have been analysed. The language levels of foreign text comprehension have been examined. The peculiarities of perceptual transformation of foreign language information while reading English sailing directions have been found out.

  5. Trail formation by ice-shoved "sailing stones" observed at Racetrack Playa, Death Valley National Park

    OpenAIRE

    Lorenz, R. D.; Norris, J. M.; Jackson, B. K.; Norris, R. D.; Chadbourne, J. W.; Ray, J.

    2014-01-01

    Trails in the usually-hard mud of Racetrack Playa in Death Valley National Park attest to the seemingly-improbable movement of massive rocks on an exceptionally flat surface. The movement of these rocks, previously described as "sliding stones", "playa scrapers", "sailing stones" etc., has been the subject of speculation for almost a century but is an exceptionally rare phenomenon and until now has not been directly observed. Here we report documentation of multiple rock mov...

  6. Evolution of the halo family in the radial solar sail circular restricted three-body problem

    Science.gov (United States)

    Verrier, Patricia; Waters, Thomas; Sieber, Jan

    2014-12-01

    We present a detailed investigation of the dramatic changes that occur in the halo family when radiation pressure is introduced into the Sun-Earth circular restricted three-body problem (CRTBP). This photo-gravitational CRTBP can be used to model the motion of a solar sail orientated perpendicular to the Sun-line. The problem is then parameterized by the sail lightness number, the ratio of solar radiation pressure acceleration to solar gravitational acceleration. Using boundary-value problem numerical continuation methods and the AUTO software package (Doedel et al. in Int J Bifurc Chaos 1:493-520, 1991) the families can be fully mapped out as the parameter is increased. Interestingly, the emergence of a branch point in the retrograde satellite family around the Earth at acts to split the halo family into two new families. As radiation pressure is further increased one of these new families subsequently merges with another non-planar family at , resulting in a third new family. The linear stability of the families changes rapidly at low values of , with several small regions of neutral stability appearing and disappearing. By using existing methods within AUTO to continue branch points and period-doubling bifurcations, and deriving a new boundary-value problem formulation to continue the folds and Krein collisions, we track bifurcations and changes in the linear stability of the families in the parameter and provide a comprehensive overview of the halo family in the presence of radiation pressure. The results demonstrate that even at small values of there is significant difference to the classical CRTBP, providing opportunity for novel solar sail trajectories. Further, we also find that the branch points between families in the solar sail CRTBP provide a simple means of generating certain families in the classical case.

  7. Electric solar-wind sail for asteroid touring missions and planetary protection

    Science.gov (United States)

    Janhunen, P.

    2014-07-01

    The electric solar-wind sail (electric sail, E-sail [1,2]) is a relatively new concept for moving around in the solar system without consuming propellant and by using the thrust provided by the natural solar wind to produce propulsion. The E-sail is based on deploying, using the centrifugal force, a set of long, thin metallic tethers and charging them to high positive voltage by actively removing negative charge from the system by an electron gun. To make the tethers resistant towards inevitable wire cuts by micrometeoroids, they must be made by bonding from multiple (typically 4) thin (25--50 μ m) aluminium wires. Production of the tethers was a technical challenge which was recently overcome. According to present numerical estimates, the E-sail could produce up to 1 N of propellantless thrust out of less than 200 kg package which is enough to give characteristic acceleration of 1 mm/s^2 to a spacecraft weighing 1 tonne, thus producing 30 km/s of delta-v per year. The thrust scales as ˜ 1/r where r is the solar distance. There are ways to control and vector the thrust enough to enable inward and outward spiralling missions in the solar system. The E-sail working principle has been indirectly measured in a laboratory, and ESTCube-1 CubeSat experiment is underway in orbit (in late March 2014 it was waiting to be started) to measure the E-sail thrust acting on a short 10-m long tether. A full-scale mission requires ˜ 1000 km of tether altogether (weighing ˜10 kg). The production of a 1-km piece of tether has been demonstrated in laboratory [3]. If the E-sail holds up its present promise, it would be ideally suited for asteroid missions because it enables production of similar level of thrust than ion engines, but needs only a small fraction of the electric power and never runs out of propellant because it does not use any (the ''propellant'' being the natural solar-wind plasma flow). Here we consider especially a mission which would tour the asteroid belt for a

  8. Visual search, movement behaviour and boat control during the windward mark rounding in sailing.

    Science.gov (United States)

    Pluijms, Joost P; Cañal-Bruland, Rouwen; Hoozemans, Marco J M; Savelsbergh, Geert J P

    2015-01-01

    In search of key-performance predictors in sailing, we examined to what degree visual search, movement behaviour and boat control contribute to skilled performance while rounding the windward mark. To this end, we analysed 62 windward mark roundings sailed without opponents and 40 windward mark roundings sailed with opponents while competing in small regattas. Across conditions, results revealed that better performances were related to gazing more to the tangent point during the actual rounding. More specifically, in the condition without opponents, skilled performance was associated with gazing more outside the dinghy during the actual rounding, while in the condition with opponents, superior performance was related to gazing less outside the dinghy. With respect to movement behaviour, superior performance was associated with the release of the trimming lines close to rounding the mark. In addition, better performances were related to approaching the mark with little heel, yet heeling the boat more to the windward side when being close to the mark. Potential implications for practice are suggested for each phase of the windward mark rounding.

  9. Recent Advances in Heliogyro Solar Sail Structural Dynamics, Stability, and Control Research

    Science.gov (United States)

    Wilkie, W. Keats; Warren, Jerry E.; Horta, Lucas G.; Lyle, Karen H.; Juang, Jer-Nan; Gibbs, S. Chad; Dowell, Earl H.; Guerrant, Daniel V.; Lawrence, Dale

    2015-01-01

    Results from recent NASA sponsored research on the structural dynamics, stability, and control characteristics of heliogyro solar sails are summarized. Specific areas under investigation include coupled nonlinear finite element analysis of heliogyro membrane blade with solar radiation pressure effects, system identification of spinning membrane structures, and solarelastic stability analysis of heliogyro solar sails, including stability during blade deployment. Recent results from terrestrial 1-g blade dynamics and control experiments on "rope ladder" membrane blade analogs, and small-scale in vacuo system identification experiments with hanging and spinning high-aspect ratio membranes will also be presented. A low-cost, rideshare payload heliogyro technology demonstration mission concept is used as a mission context for these heliogyro structural dynamics and solarelasticity investigations, and is also described. Blade torsional dynamic response and control are also shown to be significantly improved through the use of edge stiffening structural features or inclusion of modest tip masses to increase centrifugal stiffening of the blade structure. An output-only system identification procedure suitable for on-orbit blade dynamics investigations is also developed and validated using ground tests of spinning sub-scale heliogyro blade models. Overall, analytical and experimental investigations to date indicate no intractable stability or control issues for the heliogyro solar sail concept.

  10. Numerical analysis of orbital transfers to Mars using solar sails and attitude control

    Science.gov (United States)

    Pereira, M. C.; de Melo, C. F.; Meireles, L. G.

    2017-10-01

    Solar sails present a promising alternative method of propulsion for the coming phases of the space exploration. With the recent advances in materials engineering, the construction of lighter and more resistant materials capable of impelling spaceships with the use of solar radiation pressure has become increasingly viable technologically and economically. The studies, simulations and analysis of orbital transfers from Earth to Mars proposed in this work were implemented considering the use of a flat solar sail. Maneuvers considering the delivery of a sailcraft from a Low Earth Orbit to the border of the Earth’s sphere of influence and interplanetary trajectories to Mars were investigated. A set of simulations were implemented varying the attitude of the sail relative to the Sun. Results show that a sailcraft can carry out transfers with final velocity with respect to Mars smaller than the interplanetary Patched-conic approximation, although this requires a longer time of transfers, provided the attitude of the sailcraft relative to the Sun can be controlled in some points of the trajectories.

  11. Dietary supplementation and doping-related factors in high-level sailing

    Directory of Open Access Journals (Sweden)

    Rodek Jelena

    2012-12-01

    Full Text Available Abstract Background Although dietary supplements (DSs in sports are considered a natural need resulting from athletes’ increased physical demands, and although they are often consumed by athletes, data on DS usage in Olympic sailing are scarce. The aim of this study was to study the use of and attitudes towards DSs and doping problems in high-level competitive sailing. Methods The sample consisted of 44 high-level sailing athletes (5 of whom were female; total mean age 24.13 ± 6.67 years and 34 coaches (1 of whom was female; total mean age 37.01 ± 11.70. An extensive, self-administered questionnaire of substance use was used, and the subjects were asked about sociodemographic data, sport-related factors, DS-related factors (i.e., usage of and knowledge about DSs, sources of information, and doping-related factors. The Kruskal-Wallis ANOVA was used to determine the differences in group characteristics, and Spearman’s rank order correlation and a logistic regression analysis were used to define the relationships between the studied variables. Results DS usage is relatively high. More than 77% of athletes consume DSs, and 38% do so on a regular basis (daily. The athletes place a high degree of trust in their coaches and/or physicians regarding DSs and doping. The most important reason for not consuming DSs is the opinion that DSs are useless and a lack of knowledge about DSs. The likelihood of doping is low, and one-third of the subjects believe that doping occurs in sailing (no significant differences between athletes and coaches. The logistic regression found crew number (i.e., single vs. double crew to be the single significant predictor of DS usage, with a higher probability of DS consumption among single crews. Conclusion Because of the high consumption of DSs future investigations should focus on real nutritional needs in sailing sport. Also, since athletes reported that their coaches are the primary source of information about

  12. Use of a virtual reality physical ride-on sailing simulator as a rehabilitation tool for recreational sports and community reintegration: a pilot study.

    Science.gov (United States)

    Recio, Albert C; Becker, Daniel; Morgan, Marjorie; Saunders, Norman R; Schramm, Lawrence P; McDonald, John W

    2013-12-01

    Participation in sailing by people with disabilities, particularly in small sailboats, is widely regarded as having positive outcomes on self-esteem and general health for the participants. However, a major hurdle for people with no previous experience of sailing, even by those without disabilities, is the perception that sailing is elitist, expensive, and dangerous. Real-time "ride-on" sailing simulators have the potential to bridge the gap between dry-land and on-the-water sailing. These provide a realistic, safe, and easily supervised medium in which nonsailors can easily and systematically learn the required skills before venturing out on the water. The authors report a 12-wk pilot therapeutic sailing program using the VSail-Access sailing simulation system followed by on-water experience. After completion of the training, all subjects demonstrated the ability to navigate a simple course around marker buoys (triangular configuration) on the computer screen, the ability to sail independently in winds of moderate strength (up to 14 knots) on water, and measurable improvements in their psychologic health. In addition, the subjects were able to participate in a sports activity with their respective family members and experienced a sense of optimism about their future.

  13. Photogravimagnetic assists of light sails: a mixed blessing for Breakthrough Starshot?

    Science.gov (United States)

    Forgan, Duncan H.; Heller, René; Hippke, Michael

    2018-03-01

    Upon entering a star system, light sails are subject to both gravitational forces and radiation pressure, and can use both in concert to modify their trajectory. Moreover, stars possess significant magnetic fields, and if the sail is in any way charged, it will feel the Lorentz force also. We investigate the dynamics of so-called `photogravimagnetic assists' of sailcraft around α Centauri A, a potential first destination en route to Proxima Centauri (the goal of the Breakthrough Starshot programme). We find that a 10-m2 sail with a charge-to-mass ratio of around 10 μC g-1 or higher will need to take account of magnetic field effects during orbital manoeuvres. The magnetic field can provide an extra source of deceleration and deflection, and allow capture on to closer orbits around a target star. However, flipping the sign of the sailcraft's charge can radically change resulting trajectories, resulting in complex loop-de-loops around magnetic field lines and essentially random ejection from the star system. Even on well-behaved trajectories, the field can generate off-axis deflections at α Centauri that, while minor, can result in very poor targeting of the final destination (Proxima) post-assist. Fortunately for Breakthrough Starshot, nanosails are less prone to charging en route than their heavier counterparts, but can still accrue relatively high charge at both the origin and destination, when travelling at low speeds. Photogravimagnetic assists are highly non-trivial, and require careful course correction to mitigate against unwanted changes in trajectory.

  14. Optimized Trajectories to the Nearest Stars Using Lightweight High-velocity Photon Sails

    Science.gov (United States)

    Heller, René; Hippke, Michael; Kervella, Pierre

    2017-09-01

    New means of interstellar travel are now being considered by various research teams, assuming lightweight spaceships to be accelerated via either laser or solar radiation to a significant fraction of the speed of light (c). We recently showed that gravitational assists can be combined with the stellar photon pressure to decelerate an incoming lightsail from Earth and fling it around a star or bring it to rest. Here, we demonstrate that photogravitational assists are more effective when the star is used as a bumper (I.e., the sail passes “in front of” the star) rather than as a catapult (I.e., the sail passes “behind” or “around” the star). This increases the maximum deceleration at α Cen A and B and reduces the travel time of a nominal graphene-class sail (mass-to-surface ratio 8.6× {10}-4 {{g}} {{{m}}}-2) from 95 to 75 years. The maximum possible velocity reduction upon arrival depends on the required deflection angle from α Cen A to B and therefore on the binary’s orbital phase. Here, we calculate the variation of the minimum travel times from Earth into a bound orbit around Proxima for the next 300 years and then extend our calculations to roughly 22,000 stars within about 300 lt-yr. Although α Cen is the most nearby star system, we find that Sirius A offers the shortest possible travel times into a bound orbit: 69 years assuming 12.5% c can be obtained at departure from the solar system. Sirius A thus offers the opportunity of flyby exploration plus deceleration into a bound orbit of the companion white dwarf after relatively short times of interstellar travel.

  15. Scheduling Algorithm for Improving Lift (SAIL): Documentation for initial operating capability

    Energy Technology Data Exchange (ETDEWEB)

    Hawthorne, J.E.; McLaren, R.A.

    1990-04-01

    The Military Sealift Command, a component of the United States Transportation Command, is responsible for the sealift of military personnel and material during a crisis. Conceptual plans for these complex moves, called deliberate plans, are continually being prepared. A computer-based scheduling system, the Sealift Strategic Analysis Subsystem (SEASTRAT), is under development for assisting in the production of these plans. The ship scheduling portion of this system, the Scheduling Algorithm for Improving Lift (SAIL), combines linear optimization and heuristic methods to determine ship routes and cargo loadings which honor a variety of complex operational constraints.

  16. The Development of Solar Sail Propulsion for NASA Science Missions to the Inner Solar System

    Science.gov (United States)

    Montgomery, Edward E, IV; Johnson, Charles Les

    2004-01-01

    This paper examines recent assessments of the technology challenges facing solar sails, identifies the systems and technologies needing development, and the approach employed by NASA's In-space Propulsion Program in NASA to achieve near term products that move this important technology from low technology readiness level (TRL) toward the goal of application to science missions in near earth space and beyond. The status of on-going efforts to design, build, and test ground demonstrators of alternate approaches to structures (inflatable versus rigid), membrane materials, optical shape sensing, and attitude control will be presented along with planned future investments.

  17. Sailing to Komodo: Contradictions of Tourism and Development in Eastern Indonesia

    Directory of Open Access Journals (Sweden)

    Maribeth Erb

    2015-12-01

    Full Text Available Tourism is often pinpointed as a sector of growth for countries in the developing world, and this perspective has been readily accepted in Indonesia. Government officials in poorer sections of the country, such as Nusa Tenggara Timur province (NTT in eastern Indonesia, have high hopes for the role that tourism can play in developing these poorer regions. This is not surprising, given the increasing renown of the Komodo National Park, just west of the island of Flores, where the world famous Komodo dragons reside. However, how exactly tourism is supposed to raise the standard of living and aid in development in NTT province is often unclear. In this paper I want to critically look at ideas about tourism and development in NTT, by focusing on the ‘Sail Komodo’ yacht rally, a major tourism event that took place from August to September 2013. Sail Komodo was as a marine tourism event expected to boost tourist numbers, lift the standard of living of people in this province and lower poverty levels. I critically analyze this event within the context of a ‘mega event’, and show how the contradictory ideas about how the event was meant to lead to prosperity for the poor can indicate the sometimes misguided relationship posited between tourism and development.

  18. Increased electric sail thrust through removal of trapped shielding electrons by orbit chaotisation due to spacecraft body

    Directory of Open Access Journals (Sweden)

    P. Janhunen

    2009-08-01

    Full Text Available An electric solar wind sail is a recently introduced propellantless space propulsion method whose technical development has also started. The electric sail consists of a set of long, thin, centrifugally stretched and conducting tethers which are charged positively and kept in a high positive potential of order 20 kV by an onboard electron gun. The positively charged tethers deflect solar wind protons, thus tapping momentum from the solar wind stream and producing thrust. The amount of obtained propulsive thrust depends on how many electrons are trapped by the potential structures of the tethers, because the trapped electrons tend to shield the charged tether and reduce its effect on the solar wind. Here we present physical arguments and test particle calculations indicating that in a realistic three-dimensional electric sail spacecraft there exist a natural mechanism which tends to remove the trapped electrons by chaotising their orbits and causing them to eventually collide with the conducting tethers. We present calculations which indicate that if these mechanisms were able to remove trapped electrons nearly completely, the electric sail performance could be about five times higher than previously estimated, about 500 nN/m, corresponding to 1 N thrust for a baseline construction with 2000 km total tether length.

  19. Attitude and orbital dynamics modeling for an uncontrolled solar-sail experiment in low-Earth orbit

    NARCIS (Netherlands)

    Pirovano, L.; Seefeldt, P.; Dachwald, B.; Noomen, R.

    2015-01-01

    Gossamer-1 is the first project of the three-step Gossamer roadmap, the purpose of which is to develop, prove and demonstrate that solar-sail technology is a safe and reliable propulsion technique for long-lasting and high-energy missions. This paper firstly presents the structural analysis

  20. Can surf-lifeguards perform a quality cardiopulmonary resuscitation sailing on a lifeboat? A quasi-experimental study.

    Science.gov (United States)

    Barcala-Furelos, Roberto; Abelairas-Gomez, Cristian; Palacios-Aguilar, Jose; Rey, Ezequiel; Costas-Veiga, Javier; Lopez-Garcia, Sergio; Rodriguez-Nunez, Antonio

    2017-06-01

    Drowning is a high-priority public health problem around the world. The European Resuscitation Council Guidelines for Resuscitation 2015 put special emphasis on special environments like open waters. Stopping the drowning process as soon as possible and starting an early cardiopulmonary resuscitation (CPR) improve survival. Inflatable rescue boats (IRBs) are used around the world in the water rescue of drowning victims. Our objective was to test the quality of CPR performed by surf-lifeguards while sailing on an IRB. A quasi-experimental simulation trial was conducted in Tenerife (Canary Islands-Spain) on September 2015. Ten surf-lifeguards were asked to perform a 2 min CPR on manikins in four different scenarios: (1) onshore, (2) on adrift boat, (3) on a boat sailing at 5 knots and (4) on a boat sailing at 10 knots. CPR was performed individually and was measured by means of CPRmeter (Laerdal, Norway) located on the standard manikin. Repeated measures analysis of variance was used in order to analyse the differences between scenarios. The composite of all CPR variables was over 84% in all conditions, but it was lower when CPR was performed on board: onshore (96.49±3.58%) versus adrift (91.80±3.56, p=0.04), sailing at 5 knots (88.65±5.54, p=0.03) and sailing at 10 knots (84.74±5.56, p=0.001). Surf-lifeguards are able to deliver good-quality CPR even on a moving IRB, but their performance is lower than onshore. This fact should be considered in real cases to balance the risk and benefits of CPR on board. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  1. NASA's Electric Sail Propulsion System Investigations over the Past Three Years

    Science.gov (United States)

    Wiegmann, Bruce M.

    2017-01-01

    Personnel from NASA's MSFC have been investigating the feasibility of an advanced propulsion system known as the Electric Sail for future scientific missions of exploration. This team initially won a NASA Space Technology Mission Directorate (STMD) Phase I NASA Innovative Advanced Concept (NIAC) award and then a two year follow-on Phase II NIAC award. This paper documents the findings from this three year investigation. An Electric sail propulsion system is a propellant-less and extremely fast propulsion system that takes advantage of the ions that are present in the solar wind to provide very rapid transit speeds whether to deep space or to the inner solar system. Scientific spacecraft could arrive to Pluto in 5 years, to the boundary of the solar system in ten to twelve years vs. thirty five plus years it took the Voyager spacecraft. The team's recent focused activities are: 1) Developing a Particle in Cell (PIC) numeric engineering model from the experimental data collected at MSFC's Solar Wind Facility on the interaction between simulated solar wind interaction with a charged bare wire that can be applied to a variety of missions, 2) The development of the necessary tether deployers/tethers to enable successful deployment of multiple, multi km length bare tethers, 3) Determining the different missions that can be captured from this revolutionary propulsion system 4) Conceptual designs of spacecraft to reach various destinations whether to the edge of the solar system, or as Heliophysics sentinels around the sun, or to trips to examine a multitude of asteroids These above activities, once demonstrated analytically, will require a technology demonstration mission (2021 to 2023) to demonstrate that all systems work together seamlessly before a Heliophysics Electrostatic Rapid Transit System (HERTS) could be given the go-ahead. The proposed demonstration mission will require that a small spacecraft must first travel to cis-lunar space as the Electric Sail must be

  2. Set Sail

    Centers for Disease Control (CDC) Podcasts

    2009-11-17

    In this podcast, our listener wants to know if children in diapers or those who aren't toilet trained can use the swimming pools on cruise ships.  Created: 11/17/2009 by National Center for Health Marketing.   Date Released: 11/17/2009.

  3. Re-Thinking the Use of the OML Model in Electric-Sail Development

    Science.gov (United States)

    Stone, Nobie H.

    2016-01-01

    The Orbit Motion Limited (OML) model commonly forms the basis for calculations made to determine the effect of the long, biased wires of an Electric Sail on solar wind protons and electrons (which determines the thrust generated and the required operating power). A new analysis of the results of previously conducted ground-based experimental studies of spacecraft-space plasma interactions indicate that the expected thrust created by deflected solar wind protons and the current of collected solar wind electrons could be considerably higher than the OML model would suggest. Herein the experimental analysis will be summarized and the assumptions and approximations required to derive the OML equation-and the limitations they impose-will be considered.

  4. Model of Optimal Cargo Transport Structure by Full Container Ship on Predefined Sailing Route

    Directory of Open Access Journals (Sweden)

    Serđo Kos

    2004-01-01

    Full Text Available This paper presents the mathematical model for solving theproblem of defining optimal cargo transport structure, occurringwhen, on a predefined sailing route, adequate number ofcontainers of various types, masses and sizes, possibly includingRO!RO cargo, is to be selected, i.e., a "container lot" is to beestablished in loading ports with the aim of gaining maximumship profit and, at the same time, of exploiting useful load andtransport capacity of container ship as much as possible. Theimplementation of the proposed model enables considerableincrease in the efficiency of container ship operations. Themodel was tested using a numerical example with real data.The applied post-optimal analysis examines the influence ofchange in some values of the mathematical model on the resultingoptimal program.

  5. [Britton Chance (1913-2010)--from sailing to biophysics and biochemistry and back].

    Science.gov (United States)

    Wojtczak, Lech

    2011-01-01

    A short CV of Britton Chance, an outstanding American biophysicist and biochemists, who has passed away in November 2010, is presented. Chance invented and applied in biochemical research fast recording of difference spectra during chemical reactions. Due to this technique he discovered and studied formation of enzyme-substrate complexes as exemplified by the peroxidase reaction. He also described spectral changes of electron carriers of mitochondrial respiratory chain that accompany transition from the resting to the active (phosphorylating) states. Applying vibrating platinum electrode, he recorded changes in the rate of oxygen uptake by isolated mitochondria in resting and phosphorylating states and defined the so-called respiratory states, called after his name. He was the first to describe formation of reactive oxygen species by mitochondria. Britton Chance was a devoted yachtsman and won a gold medal for the United States in sailing at the 1952 Olympic Games in Helsinki.

  6. Solar Sail Attitude Control System for the NASA Near Earth Asteroid Scout Mission

    Science.gov (United States)

    Orphee, Juan; Diedrich, Ben; Stiltner, Brandon; Becker, Chris; Heaton, Andrew

    2017-01-01

    An Attitude Control System (ACS) has been developed for the NASA Near Earth Asteroid (NEA) Scout mission. The NEA Scout spacecraft is a 6U cubesat with an eighty-six square meter solar sail for primary propulsion that will launch as a secondary payload on the Space Launch System (SLS) Exploration Mission 1 (EM-1) and rendezvous with a target asteroid after a two year journey, and will conduct science imagery. The spacecraft ACS consists of three major actuating subsystems: a Reaction Wheel (RW) control system, a Reaction Control System (RCS), and an Active Mass Translator (AMT) system. The reaction wheels allow fine pointing and higher rates with low mass actuators to meet the science, communication, and trajectory guidance requirements. The Momentum Management System (MMS) keeps the speed of the wheels within their operating margins using a combination of solar torque and the RCS. The AMT is used to adjust the sign and magnitude of the solar torque to manage pitch and yaw momentum. The RCS is used for initial de-tumble, performing a Trajectory Correction Maneuver (TCM), and performing momentum management about the roll axis. The NEA Scout ACS is able to meet all mission requirements including attitude hold, slews, pointing for optical navigation and pointing for science with margin and including flexible body effects. Here we discuss the challenges and solutions of meeting NEA Scout mission requirements for the ACS design, and present a novel implementation of managing the spacecraft Center of Mass (CM) to trim the solar sail disturbance torque. The ACS we have developed has an applicability to a range of potential missions and does so in a much smaller volume than is traditional for deep space missions beyond Earth.

  7. NASA's Advanced Solar Sail Propulsion System for Low-Cost Deep Space Exploration and Science Missions that Use High Performance Rollable Composite Booms

    Science.gov (United States)

    Fernandez, Juan M.; Rose, Geoffrey K.; Younger, Casey J.; Dean, Gregory D.; Warren, Jerry E.; Stohlman, Olive R.; Wilkie, W. Keats

    2017-01-01

    Several low-cost solar sail technology demonstrator missions are under development in the United States. However, the mass saving derived benefits that composites can offer to such a mass critical spacecraft architecture have not been realized yet. This is due to the lack of suitable composite booms that can fit inside CubeSat platforms and ultimately be readily scalable to much larger sizes, where they can fully optimize their use. With this aim, a new effort focused at developing scalable rollable composite booms for solar sails and other deployable structures has begun. Seven meter booms used to deploy a 90 m2 class solar sail that can fit inside a 6U CubeSat have already been developed. The NASA road map to low-cost solar sail capability demonstration envisioned, consists of increasing the size of these composite booms to enable sailcrafts with a reflective area of up to 2000 m2 housed aboard small satellite platforms. This paper presents a solar sail system initially conceived to serve as a risk reduction alternative to Near Earth Asteroid (NEA) Scout's baseline design but that has recently been slightly redesigned and proposed for follow-on missions. The features of the booms and various deployment mechanisms for the booms and sail, as well as ground support equipment used during testing, are introduced. The results of structural analyses predict the performance of the system under microgravity conditions. Finally, the results of the functional and environmental testing campaign carried out are shown.

  8. A Simplified Method for Calculating Propeller Thrust Decrease for a Ship Sailing on a Given Shipping Lane

    Directory of Open Access Journals (Sweden)

    Zelazny Katarzyna

    2014-04-01

    Full Text Available During ship sailing on rough water, relative ship motions can be observed which make the propeller emerge from the water, and decrease its thrust as a consequence. The article presents a simplified method for calculating the thrust decrease and the time of propeller emergence from water for the ship on a regular an irregular wave. The method can be used for predicting the operating speed of the ship on a given shipping lane.

  9. The structure and evolution of sea breezes during the qingdao olympics sailing test event in 2006

    Science.gov (United States)

    Sheng, Chunyan; Xue, Ming; Gao, Shouting

    2009-01-01

    Using data from automatic surface weather stations, buoys, lidar and Doppler, the diurnal variation and the three-dimensional structure of the sea breezes near the sailing sites of the Good Luck Beijing—2006 Qingdao International Regatta from 18 to 31 August 2006 are analyzed. Results show that excluding rainy days and days affected by typhoon, the sea breezes occur nearly every day during this period. When Qingdao is located at the edge of the subtropical high at 500 hPa, the sea breeze is usually stronger, around 3-4 m s-1. It starts at around 1100 to 1300 LST and lasts about 6 hours. The direction of the sea breeze tends to be southeasterly. When Qingdao is under the control of the subtropical high, the sea breeze is usually weaker, less than 2.5 m s-1 throughout the day, and begins later, between 1300 and 1500 LST. In this case, the direction of the sea breeze is variable from easterly to southeasterly. Most sea breezes in Qingdao are very shallow, up to 300 meters deep. Strong sea breezes can reach 1.5 km in depth and can push as far as 100 km inland. If the Huanghai sea breeze moves inland and meets the sea breeze of the Jiaozhou Bay in the western part of Qingdao, the sea breeze will strengthen and form three boundaries due to the interaction of the two sea breezes.

  10. Spatial and seasonal distribution of American whaling and whales in the age of sail.

    Science.gov (United States)

    Smith, Tim D; Reeves, Randall R; Josephson, Elizabeth A; Lund, Judith N

    2012-01-01

    American whalemen sailed out of ports on the east coast of the United States and in California from the 18(th) to early 20(th) centuries, searching for whales throughout the world's oceans. From an initial focus on sperm whales (Physeter macrocephalus) and right whales (Eubalaena spp.), the array of targeted whales expanded to include bowhead whales (Balaena mysticetus), humpback whales (Megaptera novaeangliae), and gray whales (Eschrichtius robustus). Extensive records of American whaling in the form of daily entries in whaling voyage logbooks contain a great deal of information about where and when the whalemen found whales. We plotted daily locations where the several species of whales were observed, both those caught and those sighted but not caught, on world maps to illustrate the spatial and temporal distribution of both American whaling activity and the whales. The patterns shown on the maps provide the basis for various inferences concerning the historical distribution of the target whales prior to and during this episode of global whaling.

  11. Control-centric Modelling and Nonlinear Control of the Blade Sailing Phenomenon

    Science.gov (United States)

    Riazi, Mohammad

    A reduced control-centric model of a particular behaviour associated with maritime helicopter rotor systems, known as Blade Sailing Phenomenon (BSP), is developed. BSP is a transient aeroelastic phenomenon described by the large undesired flapping motion of the helicopter rotor blades during low rotor speeds under high wind and elevated sea conditions. The developed model utilizes the Unified Airloads Model to capture the aerodynamic loads and the Intrinsic Nonlinear Beam Model to capture the structural behaviour of the blade. Integrally Actuated Twist (IAT) is used as the actuation strategy and a nonlinear feedback controller based on the Lyapunov stability theorem for autonomous dynamical systems is developed to counter the BSP. To evaluate the performance of the designed controller, the reduced BSP model is then discretized in the space domain using the Galerkin Spectral Discretization Method. The results prove the promising potential of the designed controller in countering the BSP in the reduced model. A further assessment of the controller is carried out by testing its performance in a comprehensive BSP model validated against experimental data. The results prove the capability of the controller to counter the BSP in a more accurate blade model and a more realistic simulation of a maritime environment.

  12. [Efficacy of dolutegravir in treatment-experienced patients: the SAILING and VIKING trials].

    Science.gov (United States)

    Moreno, Santiago; Berenguer, Juan

    2015-03-01

    Dolutegravir is an HIV integrase inhibitor with a high genetic barrier to resistance and is active against raltegravir- and/or elvitegravir-resistant strains. The clinical development of dolutegravir for HIV infection rescue therapy is based on 3 clinical trials. In the SAILING trial, dolutegravir (5 mg once daily) in combination with 2 other antiretroviral agents was well tolerated and showed greater virological effect than raltegravir (400 mg twice daily) in the treatment of integrase inhibitor-naïve adults with virological failure infected with HIV strains with at least two-class drug resistance. The VIKING studies were designed to evaluate the efficacy of dolutegravir as rescue therapy in treatment-experienced patients infected with HIV strains with resistance mutations to raltegravir and/or elvitegravir. VIKING-1-2 was a dose-ranging phase IIb trial. VIKING-3 was a phase III trial in which dolutegravir (50 mg twice daily) formed part of an optimized regimen and proved safe and effective in this difficult-to-treat group of patients. Dolutegravir is the integrase inhibitor of choice for rescue therapy in multiresistant HIV infection, both in integrase inhibitor-naïve patients and in those previously treated with raltegravir or elvitegravir. Copyright © 2015 Elsevier España, S.L.U. All rights reserved.

  13. Surface sediment chemistry in the Olympic Games 2004 Sailing Center (Saronikos Gulf

    Directory of Open Access Journals (Sweden)

    A.P. KARAGEORGIS

    2003-06-01

    Full Text Available Construction of the Olympic Games 2004 Sailing Center is planned in the Saronikos Gulf, in the area of Agios Kosmas. A multi-disciplinary base-line study was carried out to provide background levels of inorganic and organic pollutants before the construction. Two shallow reefs (water depth 2-3 m are the predominant features in the area’s underwater topography. The reef consists of solid rock formations and pebbles, whereas sandy sediments cover predominantly the remaining seabed. Some pockets of fine-grained sand were identified within the existing marina. Sedimentary heavy metal contents were found to be low, showing only slight heavy metal enrichment, attributed mainly to heavy mineral abundance in the area. A small enrichment for lead could be related to anthropogenic sources. Patterns of low concentrations were observed for organic carbon and organic nitrogen. Conversely, the sediment petroleum hydrocarbon content was found to be relatively high, implying anthropogenic pollution related to ship effluents and increased marine traffic.

  14. Trail formation by ice-shoved "sailing stones" observed at Racetrack Playa, Death Valley National Park

    Science.gov (United States)

    Lorenz, R. D.; Norris, J. M.; Jackson, B. K.; Norris, R. D.; Chadbourne, J. W.; Ray, J.

    2014-08-01

    Trails in the usually-hard mud of Racetrack Playa in Death Valley National Park attest to the seemingly-improbable movement of massive rocks on an exceptionally flat surface. The movement of these rocks, previously described as "sliding stones", "playa scrapers", "sailing stones" etc., has been the subject of speculation for almost a century but is an exceptionally rare phenomenon and until now has not been directly observed. Here we report documentation of multiple rock movement and trail formation events in the winter of 2013-2014 by in situ observation, video, timelapse cameras, a dedicated meteorological station and GPS tracking of instrumented rocks. Movement involved dozens of rocks, forming fresh trails typically of 10s of meters length at speeds of ~5 cm s-1 and were caused by wind stress on a transient thin layer of floating ice. Fracture and local thinning of the ice decouples some rocks from the ice movement, such that only a subset of rocks move in a given event.

  15. Spatial and seasonal distribution of American whaling and whales in the age of sail.

    Directory of Open Access Journals (Sweden)

    Tim D Smith

    Full Text Available American whalemen sailed out of ports on the east coast of the United States and in California from the 18(th to early 20(th centuries, searching for whales throughout the world's oceans. From an initial focus on sperm whales (Physeter macrocephalus and right whales (Eubalaena spp., the array of targeted whales expanded to include bowhead whales (Balaena mysticetus, humpback whales (Megaptera novaeangliae, and gray whales (Eschrichtius robustus. Extensive records of American whaling in the form of daily entries in whaling voyage logbooks contain a great deal of information about where and when the whalemen found whales. We plotted daily locations where the several species of whales were observed, both those caught and those sighted but not caught, on world maps to illustrate the spatial and temporal distribution of both American whaling activity and the whales. The patterns shown on the maps provide the basis for various inferences concerning the historical distribution of the target whales prior to and during this episode of global whaling.

  16. Analysis of Wind Data for Sports Performance Design: A Case Study for Sailing Sports

    Directory of Open Access Journals (Sweden)

    Alessandro Pezzoli

    2014-11-01

    Full Text Available Environmental conditions affect outdoor sports performance. This is particularly true in some sports, especially in the sport of sailing, where environmental parameters are extremely influential as they interact directly with strategic analysis of the race area and then with strategic analysis of the performance itself. For these reasons, this research presents an innovative methodology for the strategic analysis of the race course that is based on the integrated assessment of meteorological data measured on the ground, meteorological data measured at sea during the training activities and the results of the CALMET model in hindcasting over a limited scale. The results obtained by the above analysis are then integrated into a graphical representation that provides to coaches and athletes the main strategic directions of the race course in a simple and easy-to-use way. The authors believe that the innovative methodology that has been adopted in the present research may represent a new approach to the integrated analysis of meteorological data on coastal environments. On the other hand, the results of this analysis, if presented with an appropriate technique of meta‑communication adapted to the sport sectors, can be used effectively for the improvement of athletes’ performances.

  17. Effect of sail on augmenting attitude stability of hovering VTOL vehicle supported by one-ducted-fan. Ductedter dot fan shiji VTOL ki no hover shisei anteisei eno ho no eikyo

    Energy Technology Data Exchange (ETDEWEB)

    Ando, S.; Kato, M. (Nagoya University, Nagoya (Japan). Faculty of Engineering)

    1991-07-05

    An analytical investigation was given on augmenting attitude stability of a VTOL airplane supported by one-ducted-fan, at hovering, by means of installing a sail having air resistance on a place higher than the vehicle center-of-gravity. Since the problem becomes nonlinear, the time-marching technique was used. The sail on which the emphasis was placed had an area of as less than several times as much of the duct sectional area, and a height of as less than several times as much of the duct diameter. The stabilization effect is expressed as {Delta}h = center of gravity height region providing the stability/duct diameter. Without a sail, {Delta}h was several percent, but with a sail, the value increased to about ten times as much. This increase in {Delta}h was remarkable in the direction that elevate the position of the center of gravity. More stability is obtained by increasing the sail height than by increasing the area. Substitutes to a sail, working on the same principle, could be a gas-bag and wind mill. A gas-bag, which can change its volume readily, will be able to vary the sail area easily. A wind mill could make the weight lighter than a sail, and has a possibility of varying the resistance through changing its blade pitch angle. 2 refs., 2 figs., 1 tab.

  18. Student Experiences: the 2013 Cascadia Initiative Expedition Team's Apply to Sail Program

    Science.gov (United States)

    Mejia, H.; Hooft, E. E.; Fattaruso, L.

    2013-12-01

    During the summer of 2013, the Cascadia Initiative Expedition Team led six oceanographic expeditions to recover and redeploy ocean bottom seismometers (OBSs) across the Cascadia subduction zone and Juan de Fuca plate. The Cascadia Initiative (CI) is an onshore/offshore seismic and geodetic experiment to study questions ranging from megathrust earthquakes to volcanic arc structure to the formation, deformation and hydration of the Juan de Fuca and Gorda plates with the overarching goal of understanding the entire subduction zone system. The Cascadia Initiative Expedition Team is a team of scientists charged with leading the oceanographic expeditions to deploy and recover CI OBSs and developing the associated Education and Outreach effort. Students and early career scientists were encouraged to apply to join the cruises via the Cascadia Initiative Expedition Team's Apply to Sail Program. The goal of this call for open participation was to help expand the user base of OBS data by providing opportunities for students and scientists to directly experience at-sea acquisition of OBS data. Participants were required to have a strong interest in learning field techniques, be willing to work long hours at sea assisting in OBS deployment, recovery and preliminary data processing and have an interest in working with the data collected. In total, there were 51 applicants to the Apply to Sail Program from the US and 4 other countries; 21 graduate students as well as a few undergraduate students, postdocs and young scientists from the US and Canada were chosen to join the crew. The cruises lasted from 6 to 14 days in length. OBS retrievals comprised the three first legs, of which the first two were aboard the Research Vessel Oceanus. During each of the retrievals, multiple acoustic signals were sent while the vessel completed a semi-circle around the OBS to accurately determine its position, a final signal was sent to drop the seismometer's anchor, and finally the ship and crew

  19. Solar energy for sailing boats, motor-yachts and other vehicles. Solar generator fuer Segelboote, Motoryachten o. dgl

    Energy Technology Data Exchange (ETDEWEB)

    1980-12-01

    The goal of this invention is the design of a solar generator for sailing boats, motor-yachts and other vehicles. This generator onboard the vehicle will be used for charging electric batteries. Essential features are the installation of the generator on a support, in defined distance to an installation plane. More design items have been described in 14 patent claims. Advantages are the increased efficiency of the generator and its low maintenance expenditure. The mounting frame has a high mechanical stability and the generator is characterized by a great impact strength. For this reason especially hardened glasses had been used as motor components.

  20. The SailBuoy remotely-controlled unmanned vessel: Measurements of near surface temperature, salinity and oxygen concentration in the Northern Gulf of Mexico

    OpenAIRE

    Ghani, Mahmud Hasan; Hole, Lars R.; Fer, Ilker; Kourafalou, Vassiliki H.; Wienders, Nicolas; Kang, HeeSook; Drushka, Kyla; Peddie, David

    2014-01-01

    An experimental deployment of a new type of unmanned vessel is presented. The Christian Michelsen Research SailBuoy, a remotely-controlled surface vehicle, sampled near-surface properties during a two-month mission in the northern Gulf of Mexico in March–May, 2013. Averaged over the entire deployment, the vessel speed over ground was View the MathML source42±30cm s⎻¹ (± one standard deviation) with a maximum of View the MathML source180cm s⎻¹. During the 62 days of the mission, the SailBuoy c...

  1. Development of logistic support for space equipment on the base of the “Sail-BMSTU” midget spacecraft

    Directory of Open Access Journals (Sweden)

    Brom Alla

    2016-01-01

    Full Text Available The paper envisages the application of integrated logistic support conception (ILS for space equipment on the base of the example of the student’s «Sail BMSTU» midget spacecraft (MS. The peculiarities of space equipment logistic support in operation phase are considered. The special focus is done to the problem of decrease in production expenses of spacecrafts. The paper suggests that the solution of this problem has to be based on tools commonly used in engineering fields – functional analysis and FMECA. The fragment of FMECA is presented. Due to FMECA it is clear what products in spacecrafts should be calibrated in accordance with quality requirements of military class and what ones should be calibrated in accordance with quality requirements of commercial and industrial classes. Each failure mode of midget spacecraft, identified within FMECA, is studied by assessing of criticality, severity and probability of emergence. The paper describes the main procedures of integrated logistic support on the base of the student’s «Sail MGTU» midget spacecraft. Recommended guidelines providing reliability of electro radio products are elaborated. The practical application of integrated logistic support in aerospace industry is reasonably presented.

  2. A Velocity Prediction Procedure for Sailing Yachts with a hydrodynamic Model based on integrated fully coupled RANSE-Free-Surface Simulations

    NARCIS (Netherlands)

    Boehm, C.

    2014-01-01

    One of the most important tools in today's sailing yacht design is the Velocity Prediction Program (VPP). VPPs calculate boat speed from the equilibrium of aero- and hydrodynamic flow forces. Consequently their accuracy is linked to the accuracy of the aero- and hydrodynamic data used to represent a

  3. The Heliopause Electrostatic Rapid Transit System (HERTS) Design, Trades, and Analyses Performed in a Two Year NASA Investigation of Electric Sail Propulsion Systems

    Science.gov (United States)

    Wiegmann, Bruce M.

    2017-01-01

    The Heliopause Electrostatic Rapid Transit System (HERTS) was one of the seven total Phase II NASA Innovative Advanced Concepts (NIAC) that was down-selected in 2015 for continued funding and research. In Phase I our team learned that a spacecraft propelled by an Electric Sail (E-Sail) can travel great astronomical distances, such as to the Heliopause region of the solar system (approx. 100 to 120 AU) in approximately one quarter of the time (10 years) versus the time it took the Voyager spacecraft launched in 1977 (36 years). The completed work within the Phase II NIAC funded effort builds upon the work that was done in the Phase I NIAC and is focused on: 1) Testing of plasma interaction with a charged wire in a MSFC simulated solar environment vacuum test chamber. 2) Development of a Particle-in-Cell (PIC) models that are validated in the plasma testing and used to extrapolate to the E-Sail propulsion system design. 3) Conceptual design of a Technology Demonstration Mission (TDM) spacecraft developed to showcase E-Sail propulsion systems. 4) Down selection of both: a) Materials for a multi km length conductor and, b) Best configuration of the proposed conductor deployment subsystem. This paper will document the findings to date (June, 2017) of the above focused areas.

  4. Proof-of-Concept Evaluation of the SailValve Self-Expanding Deep Venous Valve System in a Porcine Model.

    Science.gov (United States)

    Boersma, Doeke; Vink, Aryan; Moll, Frans L; de Borst, Gert J

    2017-06-01

    To evaluate the SailValve, a new self-expanding deep venous valve concept based on a single polytetrafluoroethylene cusp floating up and down in the bloodstream like a sail, acting as a flow regulator and allowing minimal reflux to reduce thrombogenicity. Both iliac veins of 5 pigs were implanted with SailValve devices; the first animal was an acute pilot experiment to show the feasibility of accurately positioning the SailValve via a femoral access. The other 4 animals were followed for 2 weeks (n=2) or 4 weeks (n=2) under a chronic implantation protocol. Patency and valve function were evaluated directly in all animals using ascending and descending phlebography after device placement and at termination in the chronic implant animals. For reasons of clinical relevance, a regimen of clopidogrel and calcium carbasalate was administered. Histological analysis was performed according to a predefined protocol by an independent pathologist. Deployment was technically feasible in all 10 iliac veins, and all were patent directly after placement. No perioperative or postoperative complications occurred. Ascending phlebograms in the follow-up animals confirmed the patency of all valves after 2 or 4 weeks. Descending phlebograms showed full function in 5 of 8 valves. Limited reflux was seen in 1 valve (4-week group), and the function in the remaining 2 valves (2-week group) was insufficient because of malpositioning. No macroscopic thrombosis was noted on histology. Histology in the follow-up groups revealed a progressive inflammatory reaction to the valves. This animal study shows the potential of the SailValve concept with sufficient valve function after adequate positioning and no (thrombogenic) occlusions after short-term follow-up. Future research is essential to optimize valve material and long-term patency.

  5. Estados de humor de velejadores durante o Pré-Panamericano Mood states sail athletes during the Pre-Panamerican

    Directory of Open Access Journals (Sweden)

    Ricardo Brandt

    2010-12-01

    Full Text Available O objetivo da presente pesquisa foi avaliar os estados de humor de velejadores após regatas do Pré-Panamericana de Vela, bem como fatores associados. A amostra foi composta por 18 atletas de ambos os sexos, que foram avaliados por meio da Escala de Humor de Brunel. Os atletas apresentaram elevada tensão e fadiga, associadas a altos níveis de vigor. Homens apresentaram maior vigor e fadiga, e menor tensão, depressão e raiva do que as mulheres, porém sem diferenças estatísticamente significativas. Quanto à classe, velejadores de classes individuais apresentaram maior tensão, depressão e confusão do que os de classes com dois tripulantes, porém sem diferenças estatísticamente significativas. Os estados de humor apresentados pelos atletas após regatas do Pré-Panamericano de Vela podem ser considerados diferente do ideal para o rendimento esportivo, porém ainda existe pouco domínio teórico dos estados de humor de velejadores para análises mais aprofundadas.The purpose of this research was to evaluate de mood states after regattas of sail during Pre-Panamerican, as well associated factors. Sample was composed by 18 athletes of both sexes that were evaluated by the Brunel Mood Scale. The athletes presented high tension and fatigue, associated with high levels of vigor. The men present higher vigor and fatigue, and low tension, depression and angry than the women, but the differences were no significant. About the class, the athletes of individual classes showed high tension, depression and confusion than the ones of the classes with two athletes, but there were no significant differences. The mood states presented by the athletes after the regattas of sail of the Pre-Panamerican can be considered different from the ideal to sporting performance, but already there is a little bit theory about the mood states of sail athletes to do a deep analysis.

  6. Sail-Type Wind Turbine for Autonomous Power Supplay: Possible Use in Latvia

    Science.gov (United States)

    Sakipova, S.; Jakovics, A.

    2014-12-01

    Under the conditions of continuous increase in the energy consumption, sharply rising prices of basic energy products (gas, oil, coal), deterioration of environment, etc., it is of vital importance to develop methods and techniques for heat and power generation from renewables. The paper considers the possibility to use a sail-type wind turbine for autonomous power supply in Latvia, taking into account its climatic conditions. The authors discuss the problems of developing a turbine of the type that would operate efficiently at low winds, being primarily designed to supply power to small buildings and farms distant from centralized electricity networks. The authors consider aerodynamic characteristics of such a turbine and the dependence of the thrust moment of its pilot model on the airflow rate at different angles of attack. The pilot model with a changeable blade shape has been tested and shows a good performance. Darbs veltīts vienam no atjaunojamo enerģiju veidiem - vēja enerģijai, analizētas tās izmantošanas iespējas. Vispirms īsi raksturota vēja enerģijas izmantošana pasaulē, kā arī vērtētas izmantošanas perspektīvas no inženiertehniskā un klimatisko apstākļu viedokļa. Turpinājumā raksturota situācija Latvijā, t. sk., arī vēja potenciāla pieejamība dažādos reģionos, kā arī vēja enerģijas izmantošanas efektivitāti raksturojošie lielumi. Konstatējot problēmu, rast vēja turbīnu risinājumus Latvijas apstākļiem ar maziem vidējiem vēja ātrumiem, izveidots buras tipa turbīnas modelis. Šī modeļa raksturlielumu izpēte veikta vēja tunelī Karagandas universitātē, konstatējot relatīvi labus efektivitātes rādītājus tiešai un pretējai vēja plūsmai. Izmantojot mērījumu rezultātus, ierosināti sistēmas uzlabojumi, kurus plānots pētīt turpmāk. Šādas sistēmas potenciāli var rast lietojumu tur, kur nepieciešami autonomi enerģijas avoti.

  7. A Velocity Prediction Procedure for Sailing Yachts with a hydrodynamic Model based on integrated fully coupled RANSE-Free-Surface Simulations

    OpenAIRE

    Boehm, C.

    2014-01-01

    One of the most important tools in today's sailing yacht design is the Velocity Prediction Program (VPP). VPPs calculate boat speed from the equilibrium of aero- and hydrodynamic flow forces. Consequently their accuracy is linked to the accuracy of the aero- and hydrodynamic data used to represent a yacht. These data are usually derived from Experimental Fluid Dynamics (EFD) or Computational Fluid Dynamics (CFD) results and processed by means of linearisation and interpolation to represent th...

  8. The Heliopause Electrostatic Rapid Transit System (HERTS) - Design, Trades, and Analyses Performed in a Two Year NASA Investigation of Electric Sail Propulsion Systems

    Science.gov (United States)

    Wiegmann, Bruce M.; Scheider, Todd; Heaton, Andrew; Vaughn, Jason; Stone, Nobie; Wright, Ken

    2017-01-01

    Personnel from NASA's MSFC have been investigating the feasibility of an advanced propulsion system known as the Electric Sail (E-Sail) for future scientific exploration missions. This team initially won a NASA Space Technology Mission Directorate (STMD) Phase I NASA Innovative Advanced Concept (NIAC) award and then a two-year follow-on Phase II NIAC award in October 2015. This paper documents the findings from this three-year investigation. An Electric sail, a propellant-less propulsion system, uses solar wind ions to rapidly travel either to deep space or the inner solar system. Scientific spacecraft could reach Pluto in 5 years, or the boundary of the solar system in ten to twelve years compared to the thirty-five plus years the Voyager spacecraft took. The team's recent focuses have been: 1) Developing a Particle in Cell (PIC) numeric engineering model from MSFC's experimental data on the interaction between simulated solar wind and a charged bare wire that can be applied to a variety of missions, 2) Determining what missions could benefit from this revolutionary propulsion system, 3) Conceptualizing spacecraft designs for various tasks: to reach the solar system's edge, to orbit the sun as Heliophysics sentinels, or to examine a multitude of asteroids.

  9. Alternative SAIL-Trp for robust aromatic signal assignment and determination of the {chi}{sub 2} conformation by intra-residue NOEs

    Energy Technology Data Exchange (ETDEWEB)

    Miyanoiri, Yohei; Takeda, Mitsuhiro [Nagoya University, Graduate School of Science, Structural Biology Research Center (Japan); Jee, JunGoo; Ono, Akira M.; Okuma, Kosuke; Terauchi, Tsutomu [Tokyo Metropolitan University, Center for Priority Areas (Japan); Kainosho, Masatsune, E-mail: kainosho@nagoya-u.jp [Nagoya University, Graduate School of Science, Structural Biology Research Center (Japan)

    2011-12-15

    Tryptophan (Trp) residues are frequently found in the hydrophobic cores of proteins, and therefore, their side-chain conformations, especially the precise locations of the bulky indole rings, are critical for determining structures by NMR. However, when analyzing [U-{sup 13}C,{sup 15}N]-proteins, the observation and assignment of the ring signals are often hampered by excessive overlaps and tight spin couplings. These difficulties have been greatly alleviated by using stereo-array isotope labeled (SAIL) proteins, which are composed of isotope-labeled amino acids optimized for unambiguous side-chain NMR assignment, exclusively through the {sup 13}C-{sup 13}C and {sup 13}C-{sup 1}H spin coupling networks (Kainosho et al. in Nature 440:52-57, 2006). In this paper, we propose an alternative type of SAIL-Trp with the [{zeta}2,{zeta}3-{sup 2}H{sub 2}; {delta}1,{epsilon}3,{eta}2-{sup 13}C{sub 3}; {epsilon}1-{sup 15}N]-indole ring ([{sup 12}C{sub {gamma},}{sup 12}C{sub {epsilon}2}] SAIL-Trp), which provides a more robust way to correlate the {sup 1}H{sub {beta}}, {sup 1}H{sub {alpha}}, and {sup 1}H{sub N} to the {sup 1}H{sub {delta}1} and {sup 1}H{sub {epsilon}3} through the intra-residue NOEs. The assignment of the {sup 1}H{sub {delta}1}/{sup 13}C{sub {delta}1} and {sup 1}H{sub {epsilon}3}/{sup 13}C{sub {epsilon}3} signals can thus be transferred to the {sup 1}H{sub {epsilon}1}/{sup 15}N{sub {epsilon}1} and {sup 1}H{sub {eta}2}/{sup 13}C{sub {eta}2} signals, as with the previous type of SAIL-Trp, which has an extra {sup 13}C at the C{sub {gamma}} of the ring. By taking advantage of the stereospecific deuteration of one of the prochiral {beta}-methylene protons, which was {sup 1}H{sub {beta}2} in this experiment, one can determine the side-chain conformation of the Trp residue including the {chi}{sub 2} angle, which is especially important for Trp residues, as they can adopt three preferred conformations. We demonstrated the usefulness of [{sup 12}C{sub {gamma}},{sup 12}C

  10. Fungi Sailing the Arctic Ocean: Speciose Communities in North Atlantic Driftwood as Revealed by High-Throughput Amplicon Sequencing.

    Science.gov (United States)

    Rämä, Teppo; Davey, Marie L; Nordén, Jenni; Halvorsen, Rune; Blaalid, Rakel; Mathiassen, Geir H; Alsos, Inger G; Kauserud, Håvard

    2016-08-01

    High amounts of driftwood sail across the oceans and provide habitat for organisms tolerating the rough and saline environment. Fungi have adapted to the extremely cold and saline conditions which driftwood faces in the high north. For the first time, we applied high-throughput sequencing to fungi residing in driftwood to reveal their taxonomic richness, community composition, and ecology in the North Atlantic. Using pyrosequencing of ITS2 amplicons obtained from 49 marine logs, we found 807 fungal operational taxonomic units (OTUs) based on clustering at 97 % sequence similarity cut-off level. The phylum Ascomycota comprised 74 % of the OTUs and 20 % belonged to Basidiomycota. The richness of basidiomycetes decreased with prolonged submersion in the sea, supporting the general view of ascomycetes being more extremotolerant. However, more than one fourth of the fungal OTUs remained unassigned to any fungal class, emphasising the need for better DNA reference data from the marine habitat. Different fungal communities were detected in coniferous and deciduous logs. Our results highlight that driftwood hosts a considerably higher fungal diversity than currently known. The driftwood fungal community is not a terrestrial relic but a speciose assemblage of fungi adapted to the stressful marine environment and different kinds of wooden substrates found in it.

  11. Sailing across the North Sea: the development of trust in a short-term high intensity environment

    Directory of Open Access Journals (Sweden)

    Kotryna K. Fraser

    2016-09-01

    Full Text Available Interpersonal trust among team members is an important phenomenon influencing working relationships and performance outcomes. However, there is a lack of empirical studies investigating the development of trust with respect to behavioural and environmental factors in a group of strangers. This exploratory, mixed method study investigated the development of two-dimensional interpersonal trust (affective and cognitive and team cohesion in a newly formed temporary team of novice adults during a seven-day sail training programme. A descriptive longitudinal case study approach was adopted in the current study. Seven crew members completed the standardised psychometric questionnaires and were interviewed during the voyage. Results suggested that the development of trust occurs over three phases; 1 initial perception of shared identity, 2 early trust and 3 two dimensional trust comprising cognitive and affective dimensions. Distinct antecedents for the development of trust at each stage were identified and the importance of the competence-oriented subcomponent of cognitive trust within this challenging environmental context was highlighted. Exploratory interpretation suggests some overlap in the antecedents of interpersonal trust and team cohesion. However, further longitudinal research must examine this relationship and establish corroborative evidence for the model of trust. This research can impact on practitioners leading programmes to better understand how trust can develop over time, and offers a pragmatic approach to investigations in real world contexts.

  12. Mass sport policy development in the Olympic City: the case of Qingdao--host to the 2008 sailing regatta.

    Science.gov (United States)

    Wang, Weiming; Theodoraki, Eleni

    2007-05-01

    The Olympic Games have emerged as a significant catalyst of urban change and leave numerous legacies to the cities and countries that host them. This article will address the impacts of the preparations for the 2008 Olympic sailing regatta on mass sport development in the host municipal city of Qingdao, China, and examine the government's mass sport policy and development interventions that are linked to the 2008 Olympic Bid and subsequent preparations. The research draws on policy-making theory to unravel the nature of change and development of mass sport in Qingdao, especially how national and local governments create new policies to promote mass sport development in Qingdao and persuade people to take regular physical activity and practise sports to improve health. The article indicates that the preparations for the event generate significant improvements in mass sport in Qingdao, such as the development of mass sport policies, increase in sports participation rates, creation of new sporting facilities, and consequent improvement of public health. Nevertheless, negative effects are also evidenced in the greater imbalance between rural and urban sports development, and the high fees for using the new water sports facilities.

  13. Sailing a safe ship: improving patient safety by enhancing the leadership skills of new consultant specialist surgeons.

    Science.gov (United States)

    Shah, Peter; Cross, Vinette; Sii, Freda

    2013-01-01

    The potential for "discontinuities in care" arising from the turbulent transition from specialist trainee to consultant specialist presents risks to patient safety. But it is easy to lose sight of the affective needs of individuals facing the burden of keeping patients safe. This article describes a 2-day program focused on new and prospective consultant specialist ophthalmic surgeons entitled "Sailing a Safe Ship" (SASS). The purpose was to facilitate understanding and analysis of their personal holistic learning needs and enhance individual agency in optimizing learning during the transition period. The program used gaming, team challenges, meta-planning, role play and professional actors, interactive presentations, and self-analysis tools to portray the real world of consultant specialist practice in terms of ill-defined problems requiring "elite communication" and effective negotiation of value differences and priorities for their resolution. Participants' insights into their individual learning were recorded in scheduled reflective sessions. The immediate impact on their learning was also considered in terms of direct (instructional) and indirect (nurturant) effects. Participants' insights reflected 4 key themes: admitting vulnerability and uncertainty, taking responsibility for managing risk, being self-aware and reflexive, and internalizing authentic leadership. Four instructional and 4 nurturant effects were revealed. Preliminary findings on long-term impact on participants' practice are outlined. Evidence from the evaluation indicated that participants felt empowered to construct a personal strategic response to unfamiliar and unanticipated workplace demands and pressures, adopt a capability mindset that would accelerate their capacity to fulfill an enhanced leadership role, and take a holistic approach to their continuing self-directed development as leaders and educators. Copyright © 2013 The Alliance for Continuing Education in the Health Professions

  14. Fellowships Have Sailed

    Science.gov (United States)

    Cooper, Kenneth J.

    2010-01-01

    Jose Lopez is an assistant professor of physics at Saint Peter's College, a Catholic school in Jersey City, New Jersey, where he has been on the tenure track since receiving his Ph.D. from Stevens Institute of Technology in 2005. Essential to the completion of his doctoral work was a fellowship from the state designed to increase faculty diversity…

  15. Sailing to White Boat

    Science.gov (United States)

    2004-01-01

    This is a composite red-green-blue image of the rock called White Boat. It is the first rock target that Spirit drove to after finishing a series of investigations on the rock Adirondack. White Boat stood out to scientists due to its light color and more tabular shape compared to the dark, rounded rocks that surround it.

  16. Valvular sail power plant

    Energy Technology Data Exchange (ETDEWEB)

    Goldwater, J.M.

    1987-08-04

    A vertical-axis feathering windmill is described comprising: (a) at least one open framework vane; (b) at least one flexible sheet having at least one vertical edge, the sheet rotatably held on the framework along one edge; (c) spar means for each sheet, comprising resilient horizontal members attached is spaced equidistant relationship along the vertical length of the sheet and attached so that the sheet is able to billow between spars; and (d) resilient means between the sheet and spar combination and its corresponding framework vane biasing the sheet and spar combination towards the framework such that wind on the leeward side of the windmill adds to its rotation. The sheet and spar combination otherwise are pivotable by the wind.

  17. Sail d’Escola, “Gran esfortz fai qui chanta ni·s deporta” (BdT 430.1

    Directory of Open Access Journals (Sweden)

    Oriana Scarpati

    2009-12-01

    Full Text Available The only extant poem by Sail d’Escola, “Gran esfortz fai qui chanta ni·s deporta”, must have been quite successful with the troubadours since its melody was reused several times. Without a doubt its interest also lies in the fact that it mentions another (or others? poem in which the troubadour has recourse to the ‘mala canso’, believing, quite rightly, that he may offend the lady who proved to be a bad ‘amigua’. The text is ambiguous: it appears to be a love song asking for forgiveness to a lady who had previously been treated badly, but it also contains hidden threats of abuse, should the lady not show herself to be once more well-disposed towards her lover. This paper will propose a new interpretation of the simile in ll. 5-7, as well as some corrections to the previous edition (Chabaneau.

  18. The Changing Tides of the Type 2 Diabetes Epidemic-Smooth Sailing or Troubled Waters Ahead? Kelly West Award Lecture 2016.

    Science.gov (United States)

    Gregg, Edward W

    2017-10-01

    The Kelly West Award for Outstanding Achievement in Epidemiology is given in memory of Kelly M. West, widely regarded as the "father of diabetes epidemiology," to an individual who has made significant contributions to the field of diabetes epidemiology. Edward W. Gregg, PhD, of the Division of Diabetes Translation, Centers for Disease Control and Prevention, Atlanta, GA, received the prestigious award at the American Diabetes Association's 76th Scientific Sessions, 10-14 June 2016, in New Orleans, LA. He presented the Kelly West Award Lecture, "Changing Tides of the Type 2 Diabetes Epidemic-Smooth Sailing or Troubled Waters Ahead?" on Sunday, 12 June 2016. © 2017 by the American Diabetes Association.

  19. Protective Effects of Calcium on Cadmium Accumulation in Co-Cultured Silver Carp (Hypophthalmichthys molitrix) and Triangle Sail Mussel (Hyriopsis cumingii).

    Science.gov (United States)

    Li, Deliang; Pi, Jie; Wang, Jianping; Zhu, Pengfei; Lei, Liuping; Zhang, Ting; Liu, Deming

    2016-12-01

    Discovering cost effective strategies to reduce cadmium (Cd) uptake is of great concern for consumer food safety in the aquaculture industry. This study investigated the protective effects of calcium (Ca) on Cd uptake in co-cultured silver carp (Hypophthalmichthys molitrix) and triangle sail mussel (Hyriopsis cumingii). The results show that Ca-depending on its applied concentration-caused a significant decrease in the Cd uptake into muscle (by 48 %-72 %), gills (by 51 %-57 %), liver (by 52 %-81 %) and kidney (by 54 %-81 %) of silver carp (p mussels (p mussel, the quality of co-cultured edible fish might improve as a consequence of the potentially reduced Cd uptake.

  20. A case study of the Secure Anonymous Information Linkage (SAIL) Gateway: A privacy-protecting remote access system for health-related research and evaluation☆

    Science.gov (United States)

    Jones, Kerina H.; Ford, David V.; Jones, Chris; Dsilva, Rohan; Thompson, Simon; Brooks, Caroline J.; Heaven, Martin L.; Thayer, Daniel S.; McNerney, Cynthia L.; Lyons, Ronan A.

    2014-01-01

    With the current expansion of data linkage research, the challenge is to find the balance between preserving the privacy of person-level data whilst making these data accessible for use to their full potential. We describe a privacy-protecting safe haven and secure remote access system, referred to as the Secure Anonymised Information Linkage (SAIL) Gateway. The Gateway provides data users with a familiar Windows interface and their usual toolsets to access approved anonymously-linked datasets for research and evaluation. We outline the principles and operating model of the Gateway, the features provided to users within the secure environment, and how we are approaching the challenges of making data safely accessible to increasing numbers of research users. The Gateway represents a powerful analytical environment and has been designed to be scalable and adaptable to meet the needs of the rapidly growing data linkage community. PMID:24440148

  1. A case study of the Secure Anonymous Information Linkage (SAIL) Gateway: a privacy-protecting remote access system for health-related research and evaluation.

    Science.gov (United States)

    Jones, Kerina H; Ford, David V; Jones, Chris; Dsilva, Rohan; Thompson, Simon; Brooks, Caroline J; Heaven, Martin L; Thayer, Daniel S; McNerney, Cynthia L; Lyons, Ronan A

    2014-08-01

    With the current expansion of data linkage research, the challenge is to find the balance between preserving the privacy of person-level data whilst making these data accessible for use to their full potential. We describe a privacy-protecting safe haven and secure remote access system, referred to as the Secure Anonymised Information Linkage (SAIL) Gateway. The Gateway provides data users with a familiar Windows interface and their usual toolsets to access approved anonymously-linked datasets for research and evaluation. We outline the principles and operating model of the Gateway, the features provided to users within the secure environment, and how we are approaching the challenges of making data safely accessible to increasing numbers of research users. The Gateway represents a powerful analytical environment and has been designed to be scalable and adaptable to meet the needs of the rapidly growing data linkage community. Copyright © 2014 The Aurthors. Published by Elsevier Inc. All rights reserved.

  2. The sail-backed reptile Ctenosauriscus from the latest Early Triassic of Germany and the timing and biogeography of the early archosaur radiation.

    Directory of Open Access Journals (Sweden)

    Richard J Butler

    Full Text Available BACKGROUND: Archosaurs (birds, crocodilians and their extinct relatives including dinosaurs dominated Mesozoic continental ecosystems from the Late Triassic onwards, and still form a major component of modern ecosystems (>10,000 species. The earliest diverse archosaur faunal assemblages are known from the Middle Triassic (c. 244 Ma, implying that the archosaur radiation began in the Early Triassic (252.3-247.2 Ma. Understanding of this radiation is currently limited by the poor early fossil record of the group in terms of skeletal remains. METHODOLOGY/PRINCIPAL FINDINGS: We redescribe the anatomy and stratigraphic position of the type specimen of Ctenosauriscus koeneni (Huene, a sail-backed reptile from the Early Triassic (late Olenekian Solling Formation of northern Germany that potentially represents the oldest known archosaur. We critically discuss previous biomechanical work on the 'sail' of Ctenosauriscus, which is formed by a series of elongated neural spines. In addition, we describe Ctenosauriscus-like postcranial material from the earliest Middle Triassic (early Anisian Röt Formation of Waldhaus, southwestern Germany. Finally, we review the spatial and temporal distribution of the earliest archosaur fossils and their implications for understanding the dynamics of the archosaur radiation. CONCLUSIONS/SIGNIFICANCE: Comprehensive numerical phylogenetic analyses demonstrate that both Ctenosauriscus and the Waldhaus taxon are members of a monophyletic grouping of poposauroid archosaurs, Ctenosauriscidae, characterised by greatly elongated neural spines in the posterior cervical to anterior caudal vertebrae. The earliest archosaurs, including Ctenosauriscus, appear in the body fossil record just prior to the Olenekian/Anisian boundary (c. 248 Ma, less than 5 million years after the Permian-Triassic mass extinction. These earliest archosaur assemblages are dominated by ctenosauriscids, which were broadly distributed across northern Pangea and

  3. The sail-backed reptile Ctenosauriscus from the latest Early Triassic of Germany and the timing and biogeography of the early archosaur radiation.

    Science.gov (United States)

    Butler, Richard J; Brusatte, Stephen L; Reich, Mike; Nesbitt, Sterling J; Schoch, Rainer R; Hornung, Jahn J

    2011-01-01

    Archosaurs (birds, crocodilians and their extinct relatives including dinosaurs) dominated Mesozoic continental ecosystems from the Late Triassic onwards, and still form a major component of modern ecosystems (>10,000 species). The earliest diverse archosaur faunal assemblages are known from the Middle Triassic (c. 244 Ma), implying that the archosaur radiation began in the Early Triassic (252.3-247.2 Ma). Understanding of this radiation is currently limited by the poor early fossil record of the group in terms of skeletal remains. We redescribe the anatomy and stratigraphic position of the type specimen of Ctenosauriscus koeneni (Huene), a sail-backed reptile from the Early Triassic (late Olenekian) Solling Formation of northern Germany that potentially represents the oldest known archosaur. We critically discuss previous biomechanical work on the 'sail' of Ctenosauriscus, which is formed by a series of elongated neural spines. In addition, we describe Ctenosauriscus-like postcranial material from the earliest Middle Triassic (early Anisian) Röt Formation of Waldhaus, southwestern Germany. Finally, we review the spatial and temporal distribution of the earliest archosaur fossils and their implications for understanding the dynamics of the archosaur radiation. Comprehensive numerical phylogenetic analyses demonstrate that both Ctenosauriscus and the Waldhaus taxon are members of a monophyletic grouping of poposauroid archosaurs, Ctenosauriscidae, characterised by greatly elongated neural spines in the posterior cervical to anterior caudal vertebrae. The earliest archosaurs, including Ctenosauriscus, appear in the body fossil record just prior to the Olenekian/Anisian boundary (c. 248 Ma), less than 5 million years after the Permian-Triassic mass extinction. These earliest archosaur assemblages are dominated by ctenosauriscids, which were broadly distributed across northern Pangea and which appear to have been the first global radiation of archosaurs.

  4. America’s Cup Sailing: Effect of Standing Arm-Cranking (“Grinding” Direction on Muscle Activity, Kinematics, and Torque Application

    Directory of Open Access Journals (Sweden)

    Simon N. Pearson

    2016-06-01

    Full Text Available Grinding is a key physical element in America’s Cup sailing. This study aimed to describe kinematics and muscle activation patterns in relation to torque applied in forward and backward grinding. Ten male America’s Cup sailors (33.6 ± 5.7 years, 97.9 ± 13.4 kg, 186.6 ± 7.4 cm completed forward and backward grinding on a customised grinding ergometer. In forward grinding peak torque (77 Nm occurred at 95° (0° = crank vertically up on the downward section of the rotation at the end of shoulder flexion and elbow extension. Backward grinding torque peaked at 35° (69 Nm following the pull action (shoulder extension, elbow flexion across the top of the rotation. During forward grinding, relatively high levels of torque (>50 Nm were maintained through the majority (72% of the cycle, compared to 47% for backward grinding, with sections of low torque corresponding with low numbers of active muscles. Variation in torque was negatively associated with forward grinding performance (r = −0.60; 90% CI −0.88 to −0.02, but positively associated with backward performance (r = 0.48; CI = −0.15 to 0.83. Magnitude and distribution of torque generation differed according to grinding direction and presents an argument for divergent training methods to improve forward and backward grinding performance.

  5. Analysing the intermittent flapping flight of a Manx Shearwater, Puffinus puffinus, and its sporadic use of a wave-meandering wing-sailing flight strategy

    Science.gov (United States)

    Spivey, R. J.; Stansfield, S.; Bishop, C. M.

    2014-06-01

    Flights of Manx Shearwaters over the Irish Sea were investigated using GPS (n = 6) and simultaneous high sample rate triaxial accelerometry (n = 1). This pelagic species executes flight through intermittent bursts of flapping flight interspersed with gliding phases while meandering low over the waves. To facilitate the analysis and interpretation of body-mounted accelerometry in these challenging circumstances we introduce a combined time and frequency domain technique allowing accurate separation of flapping from gliding, measurement of wing-beat frequency and determination of flapping duty cycle. Considerable fluctuations in cycle period and time-averaged flapping duty cycle were found. Our approach offered high temporal precision, which was crucial as half the flapping bursts were briefer than 0.8 s and half the cycle times shorter than 2.55 s. Flapping duty cycles exceeding 38% were likeliest for short range flights and ascending flights. At higher duty cycles, cycle time decreased and wing-beat frequency and amplitude was only moderately elevated. Near-continuous flapping was only observed during steep ascents and strong headwinds. During a long-range foraging flight with good GPS coverage duty cycles between 7% and 63% were observed. We posit that flapping was modulated in order to maintain a steady airspeed in somewhat variable wind and wave conditions as part of a complex wave-meandering wing-sailing flight strategy that was often effective in reducing locomotion costs. Periods of very low duty cycle flight appear to have benefited from instantaneous crosswinds exceeding 10 m s-1 with an estimated three-fold reduction in biomechanical power. Accelerometry offers a very practical tool for studying flight performance and the methods herein described can be readily adapted to other species that intermittently beat their wings.

  6. The Sail-Backed Reptile Ctenosauriscus from the Latest Early Triassic of Germany and the Timing and Biogeography of the Early Archosaur Radiation

    Science.gov (United States)

    Butler, Richard J.; Brusatte, Stephen L.; Reich, Mike; Nesbitt, Sterling J.; Schoch, Rainer R.; Hornung, Jahn J.

    2011-01-01

    Background Archosaurs (birds, crocodilians and their extinct relatives including dinosaurs) dominated Mesozoic continental ecosystems from the Late Triassic onwards, and still form a major component of modern ecosystems (>10,000 species). The earliest diverse archosaur faunal assemblages are known from the Middle Triassic (c. 244 Ma), implying that the archosaur radiation began in the Early Triassic (252.3–247.2 Ma). Understanding of this radiation is currently limited by the poor early fossil record of the group in terms of skeletal remains. Methodology/Principal Findings We redescribe the anatomy and stratigraphic position of the type specimen of Ctenosauriscus koeneni (Huene), a sail-backed reptile from the Early Triassic (late Olenekian) Solling Formation of northern Germany that potentially represents the oldest known archosaur. We critically discuss previous biomechanical work on the ‘sail’ of Ctenosauriscus, which is formed by a series of elongated neural spines. In addition, we describe Ctenosauriscus-like postcranial material from the earliest Middle Triassic (early Anisian) Röt Formation of Waldhaus, southwestern Germany. Finally, we review the spatial and temporal distribution of the earliest archosaur fossils and their implications for understanding the dynamics of the archosaur radiation. Conclusions/Significance Comprehensive numerical phylogenetic analyses demonstrate that both Ctenosauriscus and the Waldhaus taxon are members of a monophyletic grouping of poposauroid archosaurs, Ctenosauriscidae, characterised by greatly elongated neural spines in the posterior cervical to anterior caudal vertebrae. The earliest archosaurs, including Ctenosauriscus, appear in the body fossil record just prior to the Olenekian/Anisian boundary (c. 248 Ma), less than 5 million years after the Permian–Triassic mass extinction. These earliest archosaur assemblages are dominated by ctenosauriscids, which were broadly distributed across northern Pangea and which

  7. Safety and efficacy of first-line bevacizumab combination therapy in Chinese population with advanced non-squamous NSCLC: data of subgroup analyses from MO19390 (SAiL) study.

    Science.gov (United States)

    Zhou, C C; Bai, C X; Guan, Z Z; Jiang, G L; Shi, Y K; Wang, M Z; Wu, Y L; Zhang, Y P; Zhu, Y Z

    2014-05-01

    Bevacizumab is a monoclonal antibody with high antitumor activity against malignant diseases. Previous studies have demonstrated the efficacy of first-line bevacizumab combination therapy in advanced, non-squamous non-small cell lung cancer (NS-NSCLC). SAiL (MO19390), an open-label, multicenter, single-arm study, evaluated the safety and efficacy of first-line bevacizumab-based treatment in clinical practice. This report presents the results of a subgroup analysis of Chinese patients enrolled in SAiL. Chemo-naive Chinese patients with locally advanced, metastatic or recurrent NSCLC were randomized to receive Bev 15 mg/kg every 3 weeks plus carboplatin + paclitaxel for maximum of six cycles, followed by single-agent bevacizumab until disease progression. The primary endpoint was safety. Secondary endpoints included time to progression and overall survival. The Chinese intent-to-treat (ITT) population consists of 198 Chinese patients, among whom 107 (54 %) were non-smokers and 90 (45.5 %) were female. The median cycle of bevacizumab administration was 10 and median duration of bevacizumab treatment was 29.5 weeks. Only eight cases of severe adverse events were observed in the study, which were deemed to be related to bevacizumab. The incidence of AEs over grade 3 in Chinese ITT patients was generally low (signals were reported. Objective response rate in 195 evaluable Chinese patients was 68.8 %, including four complete responses (2.1 %). Time to disease progression (TTP) and overall survival were 8.8 and 18.5 months, respectively. The safety and efficacy of first-line bevacizumab-based treatment in Chinese population with advanced NS-NSCLC are consistent with those in previous studies as well as in Asian subgroup population from SAiL study. No new safety signals were reported.

  8. Microparticle impact calibration of the Arrayed Large-Area Dust Detectors in INterplanetary space (ALADDIN) onboard the solar power sail demonstrator IKAROS

    Science.gov (United States)

    Hirai, Takayuki; Cole, Michael J.; Fujii, Masayuki; Hasegawa, Sunao; Iwai, Takeo; Kobayashi, Masanori; Srama, Ralf; Yano, Hajime

    2014-10-01

    The Arrayed Large-Area Dust Detectors in INterplanetary space (ALADDIN) is an array of polyvinylidene fluoride (PVDF) based dust detectors aboard the solar power sail demonstrator named IKAROS (Interplanetary Kite-craft Accelerated by Radiation Of the Sun). The total sensor area of ALADDIN (0.54 m2) is the world's largest among the past PVDF-based dust detectors. IKAROS was launched in May 2010 and then ALADDIN measured cosmic dust impacts for 16 months while orbiting around between 0.7 and 1.1 AU. The main scientific objective of ALADDIN is to reveal number density of ≥10-μm-sized dust in the zodiacal cloud with much higher time-space resolution than that achieved by any past in-situ measurements. The distribution of ≥10-μm-sized dust can be also observed mainly with the light scattering by optical instruments. This paper gives the scientific objectives, the instrumental description, and the results of microparticle impact calibration of ALADDIN conducted in ground laboratories. For the calibration tests we used Van de Graaf accelerators (VdG), two-stage light gas guns (LGG), and a nano-second pulsed Nd:YAG laser (nsPL). Through these experiments, we obtained depolarization charge signal caused by hypervelocity impacts or laser irradiation using the flight spare of 20-μm-thick PVDF sensor and the electronics box of ALADDIN. In the VdG experiment we accelerated iron, carbon, and silver microparticles at 1-30 km/s, while in the LGG experiment we performed to shoot 100's-μm-sized particles of soda-lime glass and stainless steel at 3-7 km/s as single projectile. For interpolation to ≥10-μm size, we irradiated infrared laser at the energy of 15-20 mJ directly onto the PVDF sensor. From the signal analysis, we developed a calibration law for estimation of masses of impacted dust particles. The dynamic range of ALADDIN corresponds from 9×10-14 kg to 2×10-10 kg (4-56 μm in diameter at density of 2.0 g/cm3) at the expected impact velocity of 10 km/s at 1 AU

  9. Biogeography of the Oceans: a Review of Development of Knowledge of Currents, Fronts and Regional Boundaries from Sailing Ships in the Sixteenth Century to Satellite Remote Sensing

    Science.gov (United States)

    Priede, Imants G.

    2014-06-01

    The development of knowledge of global biogeography of the oceans from sixteenthcentury European voyages of exploration to present-day use of satellite remote sensing is reviewed in three parts; the pre-satellite era (1513-1977), the satellite era leading to a first global synthesis (1978-1998), and more recent studies since 1998. The Gulf Stream was first identified as a strong open-ocean feature in 1513 and by the eighteenth century, regular transatlantic voyages by sailing ships had established the general patterns of winds and circulation, enabling optimisation of passage times. Differences in water temperature, water colour and species of animals were recognised as important cues for navigation. Systematic collection of information from ships' logs enabled Maury (The Physical Geography of the Sea Harper and Bros. New York 1855) to produce a chart of prevailing winds across the entire world's oceans, and by the early twentieth century the global surface ocean circulation that defines the major biogeographic regions was well-known. This information was further supplemented by data from large-scale plankton surveys. The launch of the Coastal Zone Color Scanner, specifically designed to study living marine resources on board the Nimbus 7 polar orbiting satellite in 1978, marked the advent of the satellite era. Over subsequent decades, correlation of satellite-derived sea surface temperature and chlorophyll data with in situ measurements enabled Longhurst (Ecological Geography of the Sea. Academic Press, New York 1998) to divide the global ocean into 51 ecological provinces with Polar, Westerly Wind, Trade Wind and Coastal Biomes clearly recognisable from earlier subdivisions of the oceans. Satellite imagery with semi-synoptic images of large areas of the oceans greatly aided definition of boundaries between provinces. However, ocean boundaries are dynamic, varying from season to season and year to year. More recent work has focused on the study of variability of

  10. Team-building through sailing: effects on health status, job satisfaction and work performance of health care professionals involved in organ and tissue donation.

    Science.gov (United States)

    Ponzin, Diego; Fasolo, Adriano; Vidale, Enrico; Pozzi, Annalaura; Bottignolo, Elisa; Calabrò, Francesco; Rupolo, Giampietro

    2015-01-01

    The aim of this study was to evaluate the effects of a team-building learning project on job satisfaction, psychological wellbeing, and performance of health care workers involved in the process of organ and tissue donation. The project was conducted between June and September 2011 and consisted of two one-day meetings and a one week sailing, involving 20 staff members. GHQ-12, MBI-HSS, and 25 items taken from the Multidimensional Organizational Health Questionnaire (MOHQ) were used to assess health status, burnout, and job satisfaction. Results of the descriptive analyses were expressed as mean ± SD and as counts and percentages; Chi-square test was used to evaluate statistical significance of differences before and after the initiative. 6 (30,0%) participants showed the likelihood to suffering from anxiety and depression (i.e. recognized as 'cases' by the GHQ-12), 3 (15.0%) of them at baseline and 3 (15.0%), different from the previous ones, in the post-intervention. The presence of stress was revealed in 9 (45.0%) and 12 subjects (60.0%) before and after the experience, respectively (6 subjects showed the presence of stress in both circumstances). We documented 4 burnout cases, 3 (15.0%) at baseline and 1 (5.0%) after the experience. Nevertheless, about 80% of the participants showed a high degree ofjob satisfaction, in terms of positive influence of job in the professional satisfaction and of clear satisfaction for the organization, during both evaluation. In respect to 2010, the number of organ donors and that of ocular tissue donors improved of about 16% and 10%, respectively, during the year of the project and in the following year (mean value). We recognize that our team-building project for personnel involved in the stressful and demanding setting of organ and tissue donation, worthwhile and recompensing at the same time, possibly influenced the personal commitment and the quality of job provided. The high level of stress showed by participants should be

  11. UltraSail Solar Sail Flight Experiment Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A team of CU Aerospace, the University of Illinois, and ManTech SRS Technologies proposes Phase II development of a 3 kg CubeSat spacecraft for initial flight test...

  12. Smooth Sailing with Contract Services.

    Science.gov (United States)

    Fickes, Michael

    2001-01-01

    Discusses how to make the contract services relationship work smoothly for educational facilities. Covers topics of food, child care, and transportation services, along with a brief explanation of the benefits of outsourcing on-campus amenities. (GR)

  13. Spacecraft sails through comet's tail

    Science.gov (United States)

    Katzoff, Judith A.

    Comet Giacobini-Zinner may not have a conventional bow shock, but the “interaction region” where the comet's sheath collides with the solar wind is a far more turbulent plasma than had been anticipated. On September 13, 2 days after the International Cometary Explorer (ICE) became the first spacecraft ever to pass through a comet's tail (Eos, September 3, 1985, p. 625), mission scientists gathered at the National Aeronautics and Space Administration's Goddard Space Flight Center (GSFC) to review their preliminary results. One scientist attending the news conference said he understood the interaction region to be “the most turbulent region that we have seen in the solar system to date.”

  14. Estimación de la fAPAR sobre la Península Ibérica a partir de la inversión del modelo de transferencia radiativa 4SAIL2

    Directory of Open Access Journals (Sweden)

    B. Martínez

    2014-12-01

    Full Text Available El objetivo de este trabajo consiste en la estimación de la fAPAR en la Península Ibérica a partir de datos MODIS. En primer lugar, se ha simulado un conjunto de datos de reflectividades y de fAPAR a partir de los modelos de transferencia radiativa de hoja (PROSPECT y de cubiertas heterogéneas (4SAIL2. En segundo lugar, se ha entrenado un conjunto de redes neuronales artificiales (RNAs para obtener mediante inversión la relación entre la fAPAR y las reflectividades simuladas y así calcular, por último, la fAPAR de la Península Ibérica a partir de imágenes de reflectividad de MODIS. Además, se ha analizado la influencia de la configuración de observación e iluminación, nadir y oblicua. La fAPAR estimada se ha comparado con otros productos ya validados. Los resultados ponen de manifiesto que la fAPAR estimada a partir de la combinación (PROSPECT+4SAIL2+Nadir proporciona, en general, diferencias alrededor del umbral requerido por los usuarios (0.1. Esta combinación se plantea como una alternativa para estimar la fAPAR en la Península Ibérica por su capacidad para caracterizar distintos tipos de cubiertas, así como por la alta variabilidad intra-anual observada en algunos casos.

  15. Analysis of ship deformation under sailing

    OpenAIRE

    Xiuwen, Shan; Lixiang, Sun; Yi, Pu; Chuncheng, Xu

    2018-01-01

    With the help of the three-dimensional potential flow theory and the hydrodynamic analysis of the loaded ship, the wave pressure distribution and the design wave parameters of the ship under loading conditions have been analyzed. Using the method of AQWA and ANSYS co-simulation, the stress level, stress distribution and deformation of the whole ship under loading conditions are obtained. The numerical analysis results can provide an effective basis for the assessment of ship navigation safety.

  16. Mohamed Gaye' and Abdou Salam Sail

    African Journals Online (AJOL)

    Template synthesis of mononuclear, hontonuclear and heterodinuclear complexes 33 vacuum filtration, washed ..... at 1589 cm". The reaction pathway described in Scheme 2 has been formulated fo: the reaction of the aldehyde precursors and diamines with metalfll) salts andfor uranyl(VI) acetate and diall-tyl tin derivatives.

  17. Unfrozen sea : sailing the northwest passage

    Energy Technology Data Exchange (ETDEWEB)

    Byers, M. [Laval Univ., Quebec City, PQ (Canada). ArcticNet

    2007-05-15

    This article described the author's journey into the Canadian Arctic that documented the shrinking sea of Canada's Arctic region. It emphasized the loss of ecosystem and animal habitat. It addressed issues regarding Canada's claims of Arctic sovereignty over disputed waters, such as the Northwest Passage. In March 2006, the area covered during the winter by sea-ice was at an all-time low, namely 300,000 square kilometres less than the previous year. At this rate the Arctic could lose all of its sea-ice by 2030. The article also discussed phytoplankton in the Arctic which, removes carbon dioxide from the atmosphere by photosynthesis. Since the waters they live in are so cold, the phytoplankton sink into the ocean depths when they die, without decomposing. The carbon they removed from the atmosphere remains at the bottom of the sea for hundreds of years. However, as water warms up, the activity of marine bacteria that feed on the dead plankton will increase, releasing carbon dioxide back into the atmosphere. Issues related to international shipping, navigation, ownership of Arctic islands, military presence and boats in the northern channels, and political promises with respect to the Canadian Coast Guard and northern waterways were also discussed. 1 fig.

  18. 2011 Pleasure Craft Sailing Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  19. Sailing the "Seven C's" of Leadership.

    Science.gov (United States)

    Weismuller, Penny C; Willgerodt, Mayumi A; McClanahan, Rachel; Helm-Remund, Terri

    2016-01-01

    Nurses are increasingly being called upon to lead changes within health care. How do nurses and, in particular, school nurses become leaders? School nurses lead daily in their work but often do not recognize themselves as leaders. The "Five C's of Leadership"-character, commitment, connectedness, compassion, and confidence-identified by Kowalski and Yoder-Wise are foundational to the development of leadership and are particularly relevant to school nurses and their role. Two additional attributes found in the literature-courage and capacity-also undergird school nursing practice. In this article, we describe how school nurses already embody these leadership qualities. Each leadership attribute is reviewed in light of the literature, followed by specific examples to demonstrate how school nurses provide leadership. Through these illustrations, school nurses can recognize and embrace their present leadership abilities. In addition, by using the "Seven C's" of leadership, school nurses can enhance their inherent leadership abilities. © 2015 The Author(s).

  20. 2013 Pleasure Craft and Sailing Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  1. Collada sailing the gulf of 3D digital content creation

    CERN Document Server

    Arnaud, Remi

    2006-01-01

    Collada contains everything you need to get up and running to build your game, game engine or content pipeline tool. If you are a manager or decision maker, you get the added comfort of knowing that - finally - you just might be able to write that tool once and not over and over again."""" -Tony Parisi, Slashdot.org, December 2006 [The Authors] provide insight into the design of COLLADA so that readers can understand how design decisions were made and how this standard may evolve. The book will be useful to content developers interested in exchanging data between several tools, to application

  2. Traditional Sailing Ships as Indigenous Dalmatian Nautical Product

    National Research Council Canada - National Science Library

    Srećko Favro

    2015-01-01

    Modern tourist movements of the development of selective tourism forms have offered an opportunity to implement the valorisation of Croatian littoral area through the development of nautical tourism...

  3. Christiaan Huygens : Sailing and Flying on Other Worlds

    Science.gov (United States)

    Lorenz, Ralph

    2014-11-01

    In Christiaan Huygens posthumous book, "The Celestial Worlds Discover's" (1698) he lays out an optimistic vision of a universe of various worlds, some populated by beings like ourselves, and even with a few who might be scientists wondering about the same questions. He offers, in essence, a truly modern perspective on planetary physics and astrobiology.He notes that other worlds may have fluids forming clouds and rain, but that these fluids might be different from water, since for example Jupiter and Saturn are far from the sun and this 'water of ours' would be 'liable to frost.' He even speculates that other atmospheres might be thicker than ours, which would be favorable for the locomotion of the 'volatile animals.' Rather germane to present studies of Titan's seas and giant planet interiors, he even wonders if there might be layers of fluids of different densities : "There may also be many forts of Fluids ranged over one another in Rows as it were. The Sea perhaps may have such a fluid lying on it, which tho’ ten times lighter than Water, may be a hundred Time heavier than Air".Huygens considered that mariners on other worlds might use the same pulleys and anchors (noting essentially the universality of function of such devices) yet that other planets might have advantages or disadvantages for any given approach. Indeed, he rues how easy navigation must be on Jupiter and Saturn, having the benefit of so many moons from which Longitude could be determined (a vexing challenge of his day). He even notes that other worlds might have magnetic fields, allowing their sailors to use the compass. As post-Cassini exploration of Titan contemplates a number of vehicle types, from hot air balloons to sailboats which can exploit the thick atmosphere and low gravity of that environment, it is fitting to recall the perspective of Titan's discoverer on other worlds as being similar, but different. The same laws of physics and logic of design apply, but with different environmental parameters and working materials.

  4. Sailing alone: Teenage autonomy and regimes of childhood

    NARCIS (Netherlands)

    Claassen, R.J.G.

    2012-01-01

    Should society intervene to prevent the risky behavior of precocious teenagers even if it would be impermissible to intervene with adults who engage in the same risky behavior? The problem is well illustrated by the legal case of the 13-year-old Dutch girl Laura Dekker, who set out in 2009 to become

  5. Sailing between Scylla and Charybdis: Mayelane v Ngwenyama ...

    African Journals Online (AJOL)

    Mayelane v Ngwenyama 2013 4 SA 415 (CC) is arguably the most important judgment concerning the recognition of customary marriages in recent times. This article attempts to unpack some of the many issues that arise from the case, namely: (a) the practical difficulties associated with ascertaining living customary law ...

  6. Sailing in Uncharted Waters: Carefully Navigating the Polio Endgame.

    Directory of Open Access Journals (Sweden)

    Elizabeth Miller

    2016-10-01

    Full Text Available In a Perspective linked to the research article by Isobel Blake and colleagues, Elizabeth Miller and T. Jacob John discuss the path towards global polio eradication and the challenges, strategies, and necessary precautions around oral polio vaccine cessation.

  7. Sailing the Deep Blue Sea of Decaying Burgers Turbulence

    CERN Document Server

    Bauer, M; Bauer, Michel; Bernard, Denis

    1999-01-01

    We study Lagrangian trajectories and scalar transport statistics in decaying Burgers turbulence. We choose velocity fields, solutions of the inviscid Burgers equation, whose probability distributions are specified by Kida's statistics. They are time-correlated, not time-reversal invariant and not Gaussian. We discuss in some details the effect of shocks on trajectories and transport equations. We derive the inviscid limit of these equations using a formalism of operators localized on shocks. We compute the probability distribution functions of the trajectories although they do not define Markov processes. As physically expected, these trajectories are statistically well-defined but collapse with probability one at infinite time. We point out that the advected scalars enjoy inverse energy cascades. We also make a few comments on the connection between our computations and persistence problems.

  8. Set Your Sails for a Coordinated Library Media Program.

    Science.gov (United States)

    Bhalla, Pam

    1986-01-01

    A library media center-initiated social studies project with an interdisciplinary approach and direct participation by the librarian in classroom activities strengthened cooperation between librarians and teachers, provided a better understanding of curricular needs for the librarian, and helped teachers appreciate the librarian's role as a…

  9. Wave Loads on Ships Sailing in Restricted Water Depth

    DEFF Research Database (Denmark)

    Vidic-Perunovic, Jelena; Jensen, Jørgen Juncher

    2003-01-01

    moment a ship may be subjected to during its operational lifetime. Whereas the influence of forward speed and ship heading with respect to the waves usually is accounted for, the effect of water depth is seldom considered, except in non-linear time domain formulations where a confined water domain must...... be specified anyhow. Usually, two-dimensional strip theories, either linear or non-linear, are applied for actual design cases and these theories are normally based on incident deep-water waves and furthermore apply added mass and damping calculations based on infinite water depth. Only a few papers have...... in the past addressed the influence of water depth on the ship response. In an early work Kim (1968) presented results for the variation of the added mass and hydrodynamic damping and for the heave and pitch motion for a Series 60 model using a relative motion strip theory formulation. A significant reduction...

  10. Modelling sailing time and cost for inland waterway transport

    NARCIS (Netherlands)

    Hekkenberg, R.G.; van Dorsser, J.C.M.; Schweighofer, Juha

    2017-01-01

    Transport time and cost are decisive factors for shippers when they choose a mode for their transport. For inland waterway transport in particular, these aspects are more uncertain and less easy to generalize than for road and rail. This is due to the highly variable waterway conditions on

  11. Sailing in Uncharted Waters: Carefully Navigating the Polio Endgame.

    Science.gov (United States)

    Miller, Elizabeth; John, T Jacob

    2016-10-01

    In a Perspective linked to the research article by Isobel Blake and colleagues, Elizabeth Miller and T. Jacob John discuss the path towards global polio eradication and the challenges, strategies, and necessary precautions around oral polio vaccine cessation.

  12. Ice rafts not sails: Floating the rocks at Racetrack Playa

    Science.gov (United States)

    Lorenz, Ralph D.; Jackson, Brian K.; Barnes, Jason W.; Spitale, Joe; Keller, John M.

    2011-01-01

    We suggest that the existence of many of the rock-carved trails at Racetrack Playa in Death Valley National Park is predominantly due to the effect of arbitrarily weak winds on rocks that are floated off the soft bed by small rafts of ice, as also occurs in arctic tidal beaches to form boulder barricades. These ice cakes need not have a particularly large surface area if the ice is adequately thick—the ice cakes allow the rocks to move by buoyantly reducing the reaction and friction forces at the bed, not by increasing the wind drag. The parameter space of ice thickness and extent versus rock size for flotation is calculated and found to be reasonable. We demonstrate the effect with a simple experiment.

  13. STUDY OF A PROTOCOL FOR MEASURING SAIL SPORTS TRAINING

    Directory of Open Access Journals (Sweden)

    Claudio Scotton

    2015-04-01

    Full Text Available Durante l’attività agonistica i velisti incontrano molteplici difficoltà. Elenchiamo solo alcune variabili ambientali che condizionano le scelte tattiche e tecniche che possono rivelarsi vincenti o perdenti (Scotton 2007: vento, onda, corrente, umidità, temperatura dell’acqua e dell’aria, distanza del campo di regata dalla sistemazione degli atleti a terra, sole, pioggia. Da tutto ciò si evince che la Vela, rispetto ad altre specialità sportive praticate in una condizione stabile come accade in una palestra o in un campo di atletica e caratterizzate dalla prevalenza di abilità motorie sportive stereotipate (Scotton 2003, naviga, vocabolo pertinente, con maggiori difficoltà nell’individuare i carichi di lavoro interno ed esterno. Obiettivo: Scopo del presente studio è l’indagine conoscitiva delle caratteristiche antropometriche di base e di alcune capacità organico-muscolari e coordinative di velisti della classe 29er; deriva in doppio acrobatica giovanile (Federvela 2008, molto veloce in qualsiasi condizione, ma anche instabile e difficile da condurre. Il lavoro ha permesso di gettare le basi per la messa punto di un protocollo di misurazione dell’allenamento applicabile alla Vela.

  14. Setting Sail for that Country: The Utopian Urge behind Inclusion

    Science.gov (United States)

    McMaster, Christopher

    2013-01-01

    The vision for the future embedded in inclusive values has fuelled educational reform. This paper will explore the utopian drive behind inclusion. The contributions of thinkers as diverse as John Dewey, Antonio Gramsci, and Paulo Freire give impetus to efforts to create a better tomorrow. They, and those who have previously struggled for…

  15. Steering of Solar Sails Using Optical Lift Force Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This study seeks to look beyond the use of radiation pressure for thrust, and to explore a means of solar navigation whereby a solar craft would be steered by use...

  16. Presidential Address: Radio-Navigation's Transition from Sail to Steam

    Science.gov (United States)

    Blanchard, Walter F.

    My title is deliberately rather similar to that of Jed Williams' book because it was from his erudite and comprehensive work that I drew my inspiration. There are many volumes dealing with radio navaid engineering development but few, if any, about the very real and practical problems faced by navigators of interpreting, sometimes under very difficult circumstances, what they presented. Very few navigators of the 40s and 50s were expert draughtsman or academicians with degrees in mathematics or electronics, yet they were expected to comprehend and apply concepts that a few years earlier would have earned them such degrees. These fundamental problems of interpretation also seem to have been rather lost on some of those who were responsible for choosing which radio navaids to install. I have terminated my survey at the era, rather than going all the way to , not only because we have heard so much of satellites lately that it is time to give them a rest, but also because it was computers steam that got us into the modern age of automated navaids when interpretation became far easier and the need for specialists doing little else vanished. My own experience is that of an aerial navigator so I hope our marine and land-based members will not object if I confine my remarks to aviation.

  17. Pilgrims sailing the Titanic: plausibility effects on memory for misinformation.

    Science.gov (United States)

    Hinze, Scott R; Slaten, Daniel G; Horton, William S; Jenkins, Ryan; Rapp, David N

    2014-02-01

    People rely on information they read even when it is inaccurate (Marsh, Meade, & Roediger, Journal of Memory and Language 49:519-536, 2003), but how ubiquitous is this phenomenon? In two experiments, we investigated whether this tendency to encode and rely on inaccuracies from text might be influenced by the plausibility of misinformation. In Experiment 1, we presented stories containing inaccurate plausible statements (e.g., "The Pilgrims' ship was the Godspeed"), inaccurate implausible statements (e.g., . . . the Titanic), or accurate statements (e.g., . . . the Mayflower). On a subsequent test of general knowledge, participants relied significantly less on implausible than on plausible inaccuracies from the texts but continued to rely on accurate information. In Experiment 2, we replicated these results with the addition of a think-aloud procedure to elicit information about readers' noticing and evaluative processes for plausible and implausible misinformation. Participants indicated more skepticism and less acceptance of implausible than of plausible inaccuracies. In contrast, they often failed to notice, completely ignored, and at times even explicitly accepted the misinformation provided by plausible lures. These results offer insight into the conditions under which reliance on inaccurate information occurs and suggest potential mechanisms that may underlie reported misinformation effects.

  18. Ship manning innovation : an onboard measurement instrument for safe sailing

    NARCIS (Netherlands)

    Post, W.M.; Punte, P.A.J.; Rasker, P.C.; Langefeld, J.J.

    2010-01-01

    We’re investigating a new assignment of manning on board of modern coasters while maintaining the current level of safety. International marine legislation sets a high, but conservative standard to the ship’s crew, but other composition of the ship’s crew may fulfill these high standards as well.

  19. Sailing the Planets: Science from Directed Aerial Robot Explorers

    Science.gov (United States)

    Nock, K.; Pankine, A.

    2004-12-01

    In the past 50 years planetary exploration has evolved from being a subject of science fiction to a multi-billion dollar activity that embraces numerous branches of science, engineering and government on several continents, affects national policies and excites the public. The development of new observational platforms - orbiters, landers and rovers - has been central to successful exploration of the planets. The maturing of planetary exploration suggests that a unifying approach to planetary exploration - one that would reduce costs and facilitate discovery - is needed. Global Aerospace Corporation under funding from the NASA institute for Advanced Concepts (NIAC) is developing a concept for planetary exploration architecture that would provide such an approach. At the core of the architecture are the Directed Aerial Robot Explorer (DARE) platforms, which are autonomous balloons with path guidance capabilities that can deploy swarms of miniature robotic probes over multiple target areas. These platforms will observe planets in concert with orbiter(s) and surface platforms (landers and rovers) on global scales continuously for several years. Due to their relatively low cost and low power consumption balloons represent a very attractive platform for planetary exploration. Indeed, the successful Venera-Vega Project demonstrated technical feasibility of deploying a balloon on another planet and the wealth of opportunities presented by a balloon platform for planetary atmospheric and surface studies. Concepts for planetary balloon exploration of Mars, Venus, Titan and the Outer Planets have been studied. The DARE architecture revolutionizes these early concepts by providing the balloon, for the first time, a means of flight path control and autonomous navigation, and by integrating the balloon platform with innovative lightweight microprobes. In addition, DARE platforms can make concurrent observations with other observational platforms leading to a revolutionary architecture for planetary exploration. This architecture would greatly expand the planetary exploration capabilities allowing high-resolution targeted observations, and augmenting observations at atmospheric altitudes with in situ surface observations by the microprobes. The study focuses on development of the DARE concept in the context of a Mars mission. On Mars, DARE will search for biologically favorable sites on and under the surface by globally surveying the planet and "sniffing" the water and methane in the atmosphere. A survey will result in concentration maps that could help to identify promising sites for exploration. Miniature thermal-emission spectrometers and high-resolution cameras onboard the DARE platforms will image the surface and map mineralogical abundances at the resolution achieved by the Mars Exploration Rovers, but on the global scale. Magnetic field measurements from altitudes of just 6 to 12 km will provide an unprecedented opportunity to study Martian geology and geophysics, and evolution of the planet. DARE will visit Polar Regions to closely observe sublimation of polar caps during the spring and the genesis of local dust storms, and then migrate towards tropical regions to observe the formation of dust devils or trace the plumes of atmospheric water vapor. DARE could release ice penetrators over the polar cap to study the layering in the ice sheets, miniature weather and geophysical stations, rovers and crawlers while flying over highlands and lowlands, and subsurface penetrators over the areas where subsurface ice could be present. Small navigational beacons could be deployed over potential landing sites to provide assistance in precision landing of robotic and/or piloted spaceships.

  20. CFI funded icebreaker sets sail on its first international mission

    CERN Multimedia

    2003-01-01

    Today was the official inauguration ceremony of a Canadian research icebreaker. The ship, which received $27.7 million from the CFI in April 2003, provides Canadian and international researchers with a world-class facility to undertake a variety of environmental and marine science projects (1/2 page).

  1. Hidalgo Sets Sail: A School District Supports All Students in Earning College Credits

    Science.gov (United States)

    Nodine, Thad R.

    2011-01-01

    In 2005, the Hidalgo Independent School District made an ambitious commitment. In partnership with nearby University of Texas-Pan American, the University of Texas System, the Communities Foundation of Texas/Texas High School Project, and the Bill & Melinda Gates Foundation, the district promised that all of its students, not just a select…

  2. Wind cannot be Directed but Sails can be Adjusted for Malaysian Renewable Energy Progress

    Science.gov (United States)

    Palanichamy, C.; Nasir, Meseret; Veeramani, S.

    2015-04-01

    Wind energy has been the promising energy technology since 1980s in terms of percentage of yearly growth of installed capacity. However the progress of wind energy has not been evenly distributed around the world. Particularly, in South East Asian countries like Malaysia and Singapore, though the Governments are keen on promoting wind energy technology, it is not well practiced due to the low wind speeds. Owing to the recent advancements in wind turbine designs, even Malaysia is well suited for wind energy by proper choice of wind turbines. As evidence, this paper presents successful wind turbines with simulated study outcomes to encourage wind power developments in Malaysia.

  3. Great Britain in the Age of Sail: Scarce Resources, Ruthless Actions and Consequences

    Science.gov (United States)

    2015-04-01

    combatants amounted to about 250, but some 2000 civilians were killed and many more rendered homeless .74 This apparently unprovoked British attack on an...Second British Empire, 134-125. 89 L.C.F. Turner, “The Cape of Good Hope and the Anglo-French Conflict, 1797-1806,” Historical Studies: Australia and...23-46. Turner, L.C.F. "The Cape of Good Hope and the Anglo-French Conflict, 1797-1806." Historical Studies: Australia and New Zealand, vol. 2

  4. Sailing smoothly across the cultural divide: Constructing effective behavioral science presentations for medical audiences.

    Science.gov (United States)

    Myerholtz, Linda; Schirmer, Julie; Carling, Mary Anne

    2015-01-01

    Beginning behavioral science faculty, who are critical residency program contributors, face significant immediate challenges that often diminish their effectiveness and increase the time it takes to translate and reformat their expertise into relevant and meaningful educational presentations. Residency program culture and competency-based learning are quite different from the educational objectives and teaching environments found in most behavioral health training programs. The goal of this article is to provide beginning behavior science faculty, who are typically on their own and learning on the job, with a guide to the core educational perspectives and skills required as well as key resources that are available to them. Since a significant portion of behavioral science faculty's teaching time revolves around small and large group presentations, our guide focuses on how to incorporate key strategies and resources into relevant, evidenced-based and, most importantly, effective behavioral health presentations for the program's resident physicians. Specifically, our recommendations include selection of content, methods of content organization, techniques for actively engaging resident physicians in discussing the significance of the topics, and descriptions of numerous Internet resources for the primary mental health topics that concern family medicine trainees. Finally, it is emphasized that the relevant and effective use of these recommendations is dependent upon the behavioral science faculty educator's first understanding and appreciating how physicians' think, speak, and prioritize information while caring for their patients. © The Author(s) 2015.

  5. Sailing for Science: on board experiences for transferring knowledge on Historical Oceanography for Future Innovation

    Science.gov (United States)

    Garvani, Sara; Carmisciano, Cosmo; Locritani, Marina; Grossi, Luigi; Mori, Anna; Stroobant, Mascha; Schierano, Erika; De Strobel, Federico; Manzella, Giuseppe; Muzi, Enrico; Leccese, Dario; Sinapi, Luigi; Morellato, Claudio; La Tassa, Hebert; Talamoni, Roberta; Coelho, Emanuel; Nacini, Francesca

    2017-04-01

    Smart, sustainable and inclusive Blue Growth means also knowing past technology and the paths followed by ancients in order to understand and monitor marine environments. In general, history of Science is a matter that is not enough explored and explained or promoted in high schools or university official programmes, and, usually, scientist do not consider it as an important part of their curricula. However, bad or good ideas, abandoned or forgotten beliefs, concepts, opinions, do still have a great potential for inspiring present and future scientists, no matter in which historical period they may have been formulated: they should be always be taken into consideration, critically examined and observed by a very close point of view, not just as part of the intellectual framework of some obsolete 'Cabinet of Curiosities' with limited access except for the chosen few. Moreover, history of Science should be transmitted in a more practical way, with hands-on labs showing the limits and challenges that prior generations of ocean explorers, investigators and seafarers had to face in order to answer to crucial questions as self-orientation in open sea, understanding main currents and waves, predicting meteorological conditions for a safe navigation. Oceanography is a relatively young branch of science, and still needs further approvals and knowledge (National Science Foundation, 2000). The Scientific Dissemination Group (SDG) "La Spezia Gulf of Science" - made up by Research Centres, Schools and Cultural associations located in La Spezia (Liguria, Italy) - has a decadal experience in initiatives aimed at people and groups of people of all ages, who are keen on science or who can be guided in any case to take an interest in scientific matters (Locritani et al., 2015). Amongst the SDG activities, the tight relationship with the Historical Oceanography Society, the Italian Navy and the Naval Technical Museum (that collects a rich heritage of civilization, technology and culture witnesses, related to the naval history of seamanship from the origins up to nowadays), allowed the creation of a special educational format based on Historical Oceanography, for university and high school students as an integration for their curriculum. The Historical Oceanography Society has provided the major knowledges included in the ancient volumes of its archive, thanks to the availability of its members that also held theoretical and practical lessons during the course. The present paper will describe the one-week special course (about 60 hours of theory and practice with technical visits to Research centres and Museums) that has been planned to be carried out on board of the Italian Training Navy Ship (A. Vespucci) and has been organized in order to give the hints about on board life, as well as theoretical lessons on modern and historical oceanography, hands-on labs on oceanographic instruments from public and private collections, physiology of diving techniques and astronomy. The general aim of this course has been, hence, to give to excellent students all those technological but also creative and imaginative features of our past. References M. Locritani, I. Batzu, C. Carmisciano, F. Muccini, R. Talamoni, H.L. Tassa, M. Stroobant, G. Guccinelli, L. Benvenuti, M. Abbate, S. Furia, A. Benedetti, M.I. Bernardini, R. Centi, L. Casale, C. Vannucci, F. Giacomazzi, C. Marini, D. Tosi, S. Merlino, E. Mioni, F. Nacini, Feeling the pulse of public perception of science: Does research make our hearts beat faster?, in: MTS/IEEE OCEANS 2015 - Genova: Discovering Sustainable Ocean Energy for a New World, 2015. National Science Foundation, 50 Years of Ocean Discovery: National Science Foundation 1950-2000. Ocean Studies Board, National Research Council ISBN: 0-309-51744-3, 276 pages, 8.5 x 11, 2000. E.L. Mills, The Historian of Science and Oceanography After Twenty Years, Earth Sciences History. 12 (1993) 5-18. J.A. Bennett, History of Technology - McConnell Anita, Historical instruments in oceanography. London: Her Majesty's Stationery Office, 1981.

  6. Mobile sailing robot for automatic estimation of fish density and monitoring water quality.

    Science.gov (United States)

    Koprowski, Robert; Wróbel, Zygmunt; Kleszcz, Agnieszka; Wilczyński, Sławomir; Woźnica, Andrzej; Łozowski, Bartosz; Pilarczyk, Maciej; Karczewski, Jerzy; Migula, Paweł

    2013-07-01

    The paper presents the methodology and the algorithm developed to analyze sonar images focused on fish detection in small water bodies and measurement of their parameters: volume, depth and the GPS location. The final results are stored in a table and can be exported to any numerical environment for further analysis. The measurement method for estimating the number of fish using the automatic robot is based on a sequential calculation of the number of occurrences of fish on the set trajectory. The data analysis from the sonar concerned automatic recognition of fish using the methods of image analysis and processing. Image analysis algorithm, a mobile robot together with its control in the 2.4 GHz band and full cryptographic communication with the data archiving station was developed as part of this study. For the three model fish ponds where verification of fish catches was carried out (548, 171 and 226 individuals), the measurement error for the described method was not exceeded 8%. Created robot together with the developed software has features for remote work also in the variety of harsh weather and environmental conditions, is fully automated and can be remotely controlled using Internet. Designed system enables fish spatial location (GPS coordinates and the depth). The purpose of the robot is a non-invasive measurement of the number of fish in water reservoirs and a measurement of the quality of drinking water consumed by humans, especially in situations where local sources of pollution could have a significant impact on the quality of water collected for water treatment for people and when getting to these places is difficult. The systematically used robot equipped with the appropriate sensors, can be part of early warning system against the pollution of water used by humans (drinking water, natural swimming pools) which can be dangerous for their health.

  7. A Systems Engineering Approach to the Development of an Autonomous Sailing Vessel

    Science.gov (United States)

    2011-01-01

    student will be building robot sailboats for a living at any point after graduation, so the main outcome of the effort must of needs be a deeper...projects, but none so thoroughly as the autonomous robotic sailboat . In this section, we will discuss the key features of this crucial component and...States Naval Academy (USNA) have pur- sued autonomous sailboat systems development as part of their required capstone project in conjunction with students

  8. The Coupled Orbit-Attitude Dynamics and Control of Electric Sail in Displaced Solar Orbits

    National Research Council Canada - National Science Library

    Mingying Huo; He Liao; Yanfang Liu; Naiming Qi

    2017-01-01

    .... The results of stability analysis show that only some of the orbits are marginally stable. For unstable displaced orbits, linear quadratic regulator is employed to control the coupled attitude-orbit...

  9. Study of davit-launched lifeboats during lowering, water entry, release and sail-away phases

    NARCIS (Netherlands)

    Gabrielsen, O.; Helland, B.; Selnes, P.O.; Helland, L.R.; Gjersum, H.; Rooij, L. van

    2011-01-01

    This paper presents the results of the Davit-Launched Lifeboat Project (DLLBP). The project was initiated by the Norwegian Oil Industry Association (OLF) in December 2009, and was executed as a joint effort between OLF and the Norwegian Shipowners' Association (NSA). The project is a continuation of

  10. 77 FR 41902 - Special Local Regulation and Safety Zone; America's Cup Sailing Events, San Francisco, CA

    Science.gov (United States)

    2012-07-17

    ... on the public's comments, the Coast Guard intends to explore social media tools or other means to... prohibited from loitering or blocking the transit area. At the COTP's discretion, vessel movement in this... standards bodies. This rule does not use technical standards. Therefore, we did not consider the use of...

  11. Development and Initial Review of the Mark II Navy 44 Sail Training Craft

    Science.gov (United States)

    2009-03-01

    intensive training environment) • Offshore capability for trips to Bermuda with a semi-skilled crew of ten • Favorable treatment under existing rating... triangle and headsails • Existing systems by type, to be updated as directed Features to be improved: • Construction materials, scantlings and...consistent with the MK I’s. The mast height, standing rigging and fore triangle base had to be identical between the MK I and MK II. However, PYD wanted

  12. The Philippine Navy’s Strategic Sail Plan 2020: A Strong and Credible Force by 2020

    Science.gov (United States)

    2017-06-09

    United States, a lack of public consensus in the face of near constant internal security threats, and the lack of funding for new naval acquisitions.4...and informal structures to enable innovation throughout the organisation .”139 To avoid catch- phrasing they define systematic innovation as “an...that of assessing the need to separate “ organisation of militaries into land, sea and air services.”149 This concept will be explored further in

  13. Sailing the Stormy Seas: The Illness Experience of Persons with Parkinson's Disease

    Science.gov (United States)

    Stanley-Hermanns, Melinda; Engebretson, Joan

    2010-01-01

    Parkinson's disease is a chronic, progressive disorder with no known cause or promising cure. While substantial information is known about the pathophysiology, little is known about the illness experience of living with the disease. A qualitative study using an ethnographic approach was conducted to provide a rich understanding of the illness…

  14. Analysis on ice resistance and ice response of ships sailing in brash ice

    Directory of Open Access Journals (Sweden)

    WANG Chao

    2018-02-01

    Full Text Available [Objectives] In order to explore the interaction between a hull and crushed ice, [Methods] a discrete element model is combined with Euler multiphase flow. The force of a hull under different speeds and different ice levels is calculated, and the motion response of ice during ship-ice interaction discussed. The reasons for ice resistance and movement change are explained intuitively. [Results] The ice resistance of the hull is obtained, mainly due to the friction and collision of the crushed ice and hull surface, which increases with the increase of the speed, but when the speed increases to a certain value, the crushing resistance no longer increases and even reduces the trend. [Conclusions] This provides a reference for the optimization of ship type for ice zones, as well as propeller design.

  15. Mobile sailing robot for automatic estimation of fish density and monitoring water quality

    OpenAIRE

    Koprowski, Robert; Wr?bel, Zygmunt; Kleszcz, Agnieszka; Wilczy?ski, S?awomir; Wo?nica, Andrzej; Łozowski,Bartosz; Pilarczyk, Maciej; Karczewski, Jerzy; Migula, Pawe?

    2013-01-01

    Introduction The paper presents the methodology and the algorithm developed to analyze sonar images focused on fish detection in small water bodies and measurement of their parameters: volume, depth and the GPS location. The final results are stored in a table and can be exported to any numerical environment for further analysis. Material and method The measurement method for estimating the number of fish using the automatic robot is based on a sequential calculation of the number of occurren...

  16. 78 FR 42739 - Lifesaving Devices-Uninspected Commercial Barges and Sailing Vessels

    Science.gov (United States)

    2013-07-17

    ....com/items/A36_Hot_Rolled_Steel_Equal_Leg_Angle.cfm?item_id=183&size_no=19&sku_no=74&pieceLength=cut... Contractors. 327320 Ready Mix Concrete 5 500 Employee 2 Manufacturing. 423320 Brick, Stone, and Related 5 100...

  17. Soil sail content estimation in the yellow river delta with satellite hyperspectral data

    Science.gov (United States)

    Weng, Yongling; Gong, Peng; Zhu, Zhi-Liang

    2008-01-01

    Soil salinization is one of the most common land degradation processes and is a severe environmental hazard. The primary objective of this study is to investigate the potential of predicting salt content in soils with hyperspectral data acquired with EO-1 Hyperion. Both partial least-squares regression (PLSR) and conventional multiple linear regression (MLR), such as stepwise regression (SWR), were tested as the prediction model. PLSR is commonly used to overcome the problem caused by high-dimensional and correlated predictors. Chemical analysis of 95 samples collected from the top layer of soils in the Yellow River delta area shows that salt content was high on average, and the dominant chemicals in the saline soil were NaCl and MgCl2. Multivariate models were established between soil contents and hyperspectral data. Our results indicate that the PLSR technique with laboratory spectral data has a strong prediction capacity. Spectral bands at 1487-1527, 1971-1991, 2032-2092, and 2163-2355 nm possessed large absolute values of regression coefficients, with the largest coefficient at 2203 nm. We obtained a root mean squared error (RMSE) for calibration (with 61 samples) of RMSEC = 0.753 (R2 = 0.893) and a root mean squared error for validation (with 30 samples) of RMSEV = 0.574. The prediction model was applied on a pixel-by-pixel basis to a Hyperion reflectance image to yield a quantitative surface distribution map of soil salt content. The result was validated successfully from 38 sampling points. We obtained an RMSE estimate of 1.037 (R2 = 0.784) for the soil salt content map derived by the PLSR model. The salinity map derived from the SWR model shows that the predicted value is higher than the true value. These results demonstrate that the PLSR method is a more suitable technique than stepwise regression for quantitative estimation of soil salt content in a large area. ?? 2008 CASI.

  18. New Generation Energy Efficient Refractory Application in Soaking Pits of Bhilai Steel Plant, Sail

    Science.gov (United States)

    Roy, Indranil; Chintaiah, Perumetla; Bhattacharya, Ajoy Kr.; Garai, Swapan Kr.; Ray Choudhury, Pankaj Kr.; Tiwari, Laksman

    In Bhilai Steel Plant (BSP), soaking pits are used for heating ingots for successive rolling into blooms. Pits are operated at a temperature of around 1350°C. Mixed gas (Mixture of Blast Furnace gas & Coke Oven gas) of calorific value around 2040 kcal/Nm3 is used as fuel. The walls of soaking pits were lined with traditional 38% Al2O3 firebricks and top 500mm was cast with 70% Al2O3 low cement castable (LCC). This type of lining results in frequent damages due to hitting by ingots while being lifted from pit by overhead cranes thus affecting the availability of pit. Life of pits was 2 to 2.5 years in BSP with 3-4 cold repairs and 3-4 hot repairs. Energy loss through the wall is also quite high in this type of lining. To triumph over the limitations of the conventional lining, a lining design was developed for the walls which consist of special 70% Al2O3 LCC having high hot strength (HMOR) in combination with specially design flexible SS-304 anchors. Ceramic fiber blanket and insulation bricks were provided between castable and the metallic shell of the pit to minimize the heat loss. A heating schedule was developed and introduced based on available infrastructure at BSP for proper curing of modified LCC based lining. After introduction of modified lining, pit no. 14/2 is running for more than 2.5 years without any repair. To capitalize the success, two more pits i.e. 12/1 and 9/2 were converted to modified lining. These pits are also running satisfactorily for more than 1.5 years. The modification has resulted in higher availability with substantial increase in production. Shell temperature of the modified pits reduced to 90° - 140°C from 120° - 200°C of conventional pits. This shows reduction in heat loss through walls, resulting less fuel consumption and energy saving of about 18%.

  19. "Not always smooth sailing": mental health issues associated with the transition from high school to college.

    Science.gov (United States)

    Cleary, Michelle; Walter, Garry; Jackson, Debra

    2011-01-01

    Students who transition from high school to college are often excited by the new phase of their lives. However, they are exposed to circumstances and expectations which place them at risk for psychiatric disorders or that may exacerbate pre-existing problems. In this paper, we discuss risk factors and other issues associated with students transitioning to college or university life, identify challenges for health professionals, and suggest possible strategies to improve the mental health of young adults on college campuses. Academic staff and health care providers need to be aware of how best to engage and assist students during an important phase of their life. Processes and care pathways also need to be easily understood, user friendly, and appropriately resourced. It is anticipated that staff, students, and industry health care providers will benefit from a greater awareness of some of the mental health issues that may occur in higher education.

  20. I Am Sailing--Towards a Transactional Analysis of "Body Techniques"

    Science.gov (United States)

    Andersson, Joacim; Östman, Leif; Öhman, Marie

    2015-01-01

    In recent years there has been a growing interest in questions related to embodiment and learning. Within the field of "body pedagogics" great efforts have been made to develop theory and methodology that can deal with the corporeal aspects of experience and knowledge without adopting any form of dualistic conceptions of body/mind and…

  1. Barista: A Framework for Concurrent Speech Processing by USC-SAIL.

    Science.gov (United States)

    Can, Doğan; Gibson, James; Vaz, Colin; Georgiou, Panayiotis G; Narayanan, Shrikanth S

    2014-05-01

    We present Barista, an open-source framework for concurrent speech processing based on the Kaldi speech recognition toolkit and the libcppa actor library. With Barista, we aim to provide an easy-to-use, extensible framework for constructing highly customizable concurrent (and/or distributed) networks for a variety of speech processing tasks. Each Barista network specifies a flow of data between simple actors, concurrent entities communicating by message passing, modeled after Kaldi tools. Leveraging the fast and reliable concurrency and distribution mechanisms provided by libcppa, Barista lets demanding speech processing tasks, such as real-time speech recognizers and complex training workflows, to be scheduled and executed on parallel (and/or distributed) hardware. Barista is released under the Apache License v2.0.

  2. Physarum Boats: If Plasmodium Sailed It Would Never Leave a Port

    Directory of Open Access Journals (Sweden)

    Andrew Adamatzky

    2010-01-01

    Full Text Available Plasmodium of Physarum polycephalum is a single huge (visible by naked eye cell with a myriad of nuclei. The plasmodium is a promising substrate for non-classical, nature-inspired computing devices. It is capable of approximation of the shortest path in a maze, computation of planar proximity graphs and plane tessellations, primitive memory and decision making. The unique properties of the plasmodium make it an ideal candidate for a role of amorphous biological robots with massive parallel information processing and distributed inputs and outputs. We show that when adhered to a lightweight object resting on a water surface the plasmodium can propel the object by oscillating its protoplasmic pseudopodia. In experimental laboratory conditions and computational experiments we study phenomenology of the plasmodium-floater system, and possible mechanisms of controlling motion of objects propelled by on-board plasmodium.

  3. Sailing from Massalia, or Mapping Out the Significance of Encolpius’ Travels in the Satyrica

    DEFF Research Database (Denmark)

    Jensson, Gottskálk

    2017-01-01

    The aim of this paper is to suggest a way of reading the severely fragmented text of the Satyrica by investigating the literary and cultural significance of the Massaliotic identity of Encolpius, the narrator and fictional author of this ancient Graeco-Roman traveler’s tale by Petronius. I argue...

  4. Square Sails on the Chilkoot Trail: The Vernacular Watercraft of the Klondike Gold Rush

    OpenAIRE

    Corbin, Sarah R.

    2010-01-01

    This thesis examines the vernacular watercraft of the Klondike Gold Rush (1897-1900). Thousands of gold seekers from around the world reached the Klondike gold fields by traversing the Chilkoot and White Pass Trails, then building over 8,000 wooden vessels, used to navigate Canada’s Upper Yukon River. Only a few remains of the gold rush flotilla have been found, and the vessels have thus far received little attention. Historical, archaeological, and photographic evidence have been used to ide...

  5. Fiber-Optic Shape Sensing for Intelligent Solar Sail Deployment Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Luna Innovations proposes to develop a distributed fiber-optic shape sensor to provide a control system for the deployment of ultra-lightweight inflatable support...

  6. 75 FR 41373 - Special Local Regulations for Marine Events; Port Huron to Mackinac Island Sail Race

    Science.gov (United States)

    2010-07-16

    .... The likely combination of congested waterways, vessels engaged in a regatta, and fast currents could... an assessment of potential costs and benefits under section 6(a)(3) of that Order. The Office of...

  7. Wing profile design of the world championship sail plane SB 11

    Science.gov (United States)

    Horstmann, K. H.; Quast, A.

    1980-01-01

    A glider capable of climbing while circling in an updraft at low speed with a great mount of lift while gliding to the next updraft at high speed and with minimal altitude loss was designed. The wing profile design alleviates several problems and leaves no gap between wind and flap. A constant thickness flap eliminates the need for a flexible contour section which in turn reduces control effort. The conventional method of banking with ailerons is retained. Improved performance is demonstrated.

  8. 77 FR 4501 - Special Local Regulation and Safety Zone; America's Cup Sailing Events, San Francisco, CA

    Science.gov (United States)

    2012-01-30

    ... designated race area, and create a temporary safety zone around racing vessels. DATES: Comments and related... between 6 p.m. and 8 p.m. on March 6, 7, and 8, 2012. ADDRESSES: You may submit comments identified by... public meetings on this proposed rule on March 6, 7, and 8, 2012. All meetings will be held from 6 p.m...

  9. 78 FR 32990 - Special Local Regulation and Safety Zone; America's Cup Sailing Events, San Francisco, CA

    Science.gov (United States)

    2013-06-03

    ... the on-water activities associated with the ``Louis Vuitton Cup, Red Bull Youth America's Cup and the... activities associated with the ``Louis Vuitton Cup, Red Bull Youth America's Cup and the 34th America's Cup... published in association with the ``Louis Vuitton Cup, Red Bull Youth America's Cup and the 34th America's...

  10. A New Sail-Backed Styracosternan (Dinosauria: Ornithopoda) from the Early Cretaceous of Morella, Spain.

    Science.gov (United States)

    Gasulla, José Miguel; Escaso, Fernando; Narváez, Iván; Ortega, Francisco; Sanz, José Luis

    2015-01-01

    A new styracosternan ornithopod genus and species is here described based on a partial postcranial skeleton and an associated dentary tooth of a single specimen from the Arcillas de Morella Formation (Early Cretaceous, late Barremian) at the Morella locality, (Castellón, Spain). Morelladon beltrani gen. et sp. nov. is diagnosed by eight autapomorphic features. The set of autapomorphies includes: very elongated and vertical neural spines of the dorsal vertebrae, midline keel on ventral surface of the second to fourth sacral vertebrae restricted to the anterior half of the centrum, a posterodorsally inclined medial ridge on the postacetabular process of the ilium that meets its dorsal margin and distal end of the straight ischial shaft laterally expanded, among others. Phylogenetic analyses reveal that the new Iberian form is more closely related to its synchronic and sympatric contemporary European taxa Iguanodon bernissartensis and Mantellisaurus atherfieldensis, known from Western Europe, than to other Early Cretaceous Iberian styracosternans (Delapparentia turolensis and Proa valdearinnoensis). The recognition of Morelladon beltrani gen. et sp. nov. indicates that the Iberian Peninsula was home to a highly diverse medium to large bodied styracosternan assemblage during the Early Cretaceous.

  11. Design of a free-rotating wing sail for an autonomous sailboat

    OpenAIRE

    Tretow, Claes

    2017-01-01

    There is an accelerating need for ocean sensing where autonomous vehicles can play a key role in assisting engineers, researcher and scientists with environmental monitoring and colleting oceanographic data. This thesis is performed in collaboration with a research group at The Royal Institute of Technology that currently develops an autonomous sailboat to be used as a sensor carrying platform for autonomous data acquisition in the Baltic Sea. This type of vehicle has potentials to be a helpf...

  12. 77 FR 22706 - Special Local Regulation and Safety Zone; America's Cup Sailing Events, San Francisco, CA

    Science.gov (United States)

    2012-04-17

    ... ``USCG-2011-0551'' and click ``Search.'' Then click the ``Open Docket Folder'' in the ``Actions'' column... National Environmental Policy Act of 1969 (NEPA) (42 U.S.C. 4321-4370f), Department of Homeland Security...

  13. [Medical support of the Navy ships during long-term sailing].

    Science.gov (United States)

    Sementsov, V K; Salenko, Iu A; Khankevich, Iu R

    2008-07-01

    The article presents peculiarities of organization of medical equipment of ships on service. The main of them are: a big farness from the base, necessity of realizing a qualified medical aid on the board because of uncapability of evacuation the patients to medical treatment facility in time, unsteady sanitarian-epidemiological status in areas of floats and in places of put in, influence of negative factors of inhabitation of ships, which calls different changes in functional condition of staff. Medical security consists of 3 parts: avance-float period, float period and after-float period. Such periodicity allows dividing efforts of medical security more professionally. The authors presents data, based on the experience of medical securing of the ships of crash team, created in the Northern Navy during the period from 3.12.2007 to 3.02.2008, realized a float from the base to Mediterranean Sea and back. Total distance was 15 sea miles, total duration was 62 days.

  14. Sommeil et course au large en solitaire : comportements des coureurs et étude de faisabilité d’un « agenda interactif de sommeil » Sleep and solo sailing racing : behaviour of racers and feasibility study of an “interactive sleep diary” Sueño y regata a vela en solitario : comportamientos de los corredores y Estudio de factibilidad de una “agenda interactiva de sueño”

    Directory of Open Access Journals (Sweden)

    Denis Theunynck

    2010-05-01

    exister un seuil critique de dette de sommeil en dessous duquel on observerait une fréquence plus élevée d’incidents et d’accidents. Cette étude préliminaire sera poursuivie par une observation à plus grande échelle afin de pouvoir valider l’ « agenda interactif de sommeil » comme outil de routine tant descriptif que d’apprentissage.Solo sailing racing associates intense and prolonged (10 to 100 days physical and cognitive effort under extreme conditions. It involves split sleep and short rest periods distributed throughout the day and night. These difficulties are mentioned to explain incidents, accidents and changes in performance.This study identifies the strategies used by nine of the best solo skippers to prepare and then manage these constraints during a race. It then follows one of the skippers for a one-hundred-day non-stop solo race around the world.Based on these observations, it was proposed to one skipper that he test an interactive “sleep” diary so that he could learn how to manage his periods of sleep in an optimal way during a race.This study shows that the subjects are aware of the importance of managing their periods of rest, but use few sleep preparation and management strategies before and during their race. They undergo an adaptation period to these extreme conditions for 24 to 72 hours and then experience periods of extreme fatigue with hallucinations. This fatigue has consequences on their performance, but also on accidentology, which seems much greater with a possible time lag of up to 72 hours after an excessive sleep debt. Laboratory tools, which could provide interesting information only with continuous use, are very difficult to use under these extreme conditions.Under these circumstances, an interactive sleep diary, used by the subject to record and manage the distribution and duration of his periods of sleep, seems to be an individual solution for managing the wake and sleep cycle. A critical sleep-debt threshold may

  15. Particularities of the education to sail of the students-woman high educational institutions not profiled in the physical culture

    Directory of Open Access Journals (Sweden)

    Nikolskyy A.U.

    2010-02-01

    Full Text Available A question is considered about the necessity of the use of factor of co-ordinating inclination to swimming locomotion by lower extremities. The criterion of differentiation of process of the elementary training swimming of students is indicated. The features of inclinations of students are certain to mastering of method of swimming. These features of ontogenetic show up in form bear dynamic and kinematics inclinations. They are related to two types of formation of motive forces in swimming: shake and shove. Described and recommended one choice of sporting methods of swimming (breast-stroke or crawl.

  16. Hydrodynamic Data for Manoeuvring and Control of an AUV Determined by Tank Tests and Free-Sailing Trials

    DEFF Research Database (Denmark)

    Aage, Christian

    1998-01-01

    these properties and to program the control systemm comprise added mass and inertia coefficients, damping, lift and drag coefficients of the vehicle and its control surfaces, as well as resistance and propulsion characteristics. Only few hydrodynamic data for AUVs have yet been published, so dedicated tests...

  17. Sailing The Calm And Rough Seas: The Influence Of Wealth And Sovereignty In Southeast Asian Maritime Disputes

    Science.gov (United States)

    2016-03-01

    1993), 1380. 65 Douglas W. Steinshouer et al., “Maps Showing Geology , Oil and Gas Fields, and Geological Provinces of the Asia Pacific Region,” Open...archipelagic country, Indonesia uses Karimun Kecil Island, Nipah Island, Pelampong Island, Helen Mars Rock, Benteng Rock, Berhanti Stone, and Nongsa...Peter J. McCabe, and Robert T. Ryder. “Maps Showing Geology , Oil and Gas Fields, and Geological Provinces of the Asia Pacific Region.” Open-File

  18. 77 FR 18984 - Special Local Regulation for Marine Events; Yorktown Parade of Sail, York River; Yorktown, VA

    Science.gov (United States)

    2012-03-29

    ... Tourism. River bounded by the north and south shores of the York River and to the west by the Coleman... River; Yorktown, VA AGENCY: Coast Guard, DHS. ACTION: Notice of proposed rulemaking. [[Page 18985..., a parade of five tall ships and 195 other vessels, to be held on the waters of York River, Yorktown...

  19. Improvements in EPIC3-Link to Hull, Improved Equation-of-State, Improved Fracture Modelling, Sail Update System, Other Improvements

    Science.gov (United States)

    1981-06-01

    calculations were charged to make input simpler, to incorporate a physically realis- tic failure model and a thermal softening model consistent with...VIEW CYCLE lAXES IFAIL XMAX, XMIN, YMAX, YMIN, ZMAX, ZMIN lEYE , YEYE, ZEYE is a code specifying the view requested. VIEW=1,2,3 requests two

  20. Delta Lloyd solar boat team; sailing 30km/h with a solar-powered boat, using hydrofoils

    NARCIS (Netherlands)

    Tra, M.

    2013-01-01

    Every two years since 2006, the Delta Lloyd Solar Boat Team builds a boat to participate in the World Cup for solar-powered boats, across the ‘Elfsteden-route’, the famous tour of the eleven cities in the Dutch province of Friesland. The upcoming year the team, consisting of a new group of students,

  1. Delta Lloyd solar boat team; sailing 30km/h with a solar-powered boat, using hydrofoils

    OpenAIRE

    Tra, M.

    2013-01-01

    Every two years since 2006, the Delta Lloyd Solar Boat Team builds a boat to participate in the World Cup for solar-powered boats, across the ‘Elfsteden-route’, the famous tour of the eleven cities in the Dutch province of Friesland. The upcoming year the team, consisting of a new group of students, will start designing and building the 2014 Solar Boat.

  2. From Rowing Between Two Reefs to Sailing in Two Oceans: The End of A Thousand Friends, Zero Enemies

    Science.gov (United States)

    2015-12-01

    of MASTER OF ARTS IN SECURITY STUDIES (STABILIZATION AND RECONSTRUCTION ) from the NAVAL POSTGRADUATE SCHOOL December 2015 Approved by: Michael S...Axis IUU Illegal, Unreported, and Unregulated KIARA Koalisi Rakyat untuk Keadilan Perikanan (The People’s Coalition for Fisheries Justice) KIH...KKP Kementerian Kelautan dan Perikanan (Ministry of Marine Affairs and Fisheries ) KKS Kartu Keluarga Sejahtera (Family Welfare Card) KMP Koalisi

  3. Translating key methodological issues into technological advancements when running in-situ experiments in sports: An example from sailing

    NARCIS (Netherlands)

    Pluijms, J.P.; Canal Bruland, R.; Kats, S.; Savelsbergh, G.J.P.

    2013-01-01

    In recent years there has been an increasing interest in capturing and understanding skilled performance by studying complex perceptual-motor skills. In this context, we identify and discuss key methodological issues that are particularly relevant when aiming to translate sport scientific knowledge

  4. Sailing the Open Polar Sea...Again: What Are You Teaching Your Children about the Arctic Ocean?

    Science.gov (United States)

    Stockard, James W. Jr.

    1989-01-01

    Relates how a blunder about the Arctic Ocean and the polar ice cap made by the author in his first year of teaching led to a successful learning experience. Lists five important discussion topics that social studies teachers should use to teach about this remote, but strategic, part of the world. (LS)

  5. 76 FR 6182 - Requested Administrative Waiver of the Coastwise Trade Laws

    Science.gov (United States)

    2011-02-03

    ... vessel LYRIC is: Intended Commercial Use of Vessel: ``Sailing Kayak trips (passengers would Kayak to a location with a local Kayak Company and then Sail back to town aboard Sailing Vessel Lyric) and possible...

  6. Heliogyro Orbital Control Authority

    NARCIS (Netherlands)

    Heiligers, M.J.; Guerrant, D.; Lawrence, D

    2015-01-01

    Solar sailing is an elegant form of space propulsion that reflects solar photons to produce thrust. Different sail configurations exist, including a traditional flat sail (either square- or disc-shaped) and a heliogyro, which divides the sail membrane into a number of long, slender blades, analogous

  7. 78 FR 33150 - Requested Administrative Waiver of the Coastwise Trade Laws: Vessel BLACK ICE; Invitation for...

    Science.gov (United States)

    2013-06-03

    ... Maritime Administration Requested Administrative Waiver of the Coastwise Trade Laws: Vessel BLACK ICE... of the vessel BLACK ICE is: Intended Commercial Use Of Vessel: Small passenger sails. Sightseeing, dinner sails, sailing classes, and eco sails. Geographic Region: ``Texas, Louisiana, Mississippi, Alabama...

  8. 77 FR 13694 - Requested Administrative Waiver of the Coastwise Trade Laws: Vessel CHANGING CHANNELS; Invitation...

    Science.gov (United States)

    2012-03-07

    ...., Washington, DC 20590. You may also send comments electronically via the Internet at http://www.regulations... used for teaching sailing classes and for sailboat charters in San Diego and Long Beach. Our sailing club owns a fleet of sailboats used to teach sailing classes from Basic Keelboat Sailing through...

  9. Approximating the Added Resistance Coefficient for a Bulk Carrier Sailing in Head Sea Conditions Based on its Geometrical Parameters and Speed

    Directory of Open Access Journals (Sweden)

    Cepowski Tomasz

    2016-12-01

    Full Text Available The article presents the mathematical function to calculate the added wave resistance transfer function for bulk carriers. Based on this function, the statistical mean added wave resistance generated by an irregular head wave with arbitrary statistical parameters can be forecasted. The input parameters are: waterplane area, waterplane coefficient, ship speed, and frequency of the regular wave. The model has been developed based on the theory of artificial neural networks. The presented function can be used in design analyses, and for planning shipping routes in situations when basic geometrical parameters of the hull are only available and not the full technical documentation. The article presents sample cases of use of this function to calculate the added wave resistance transfer function and the statistical mean added wave resistance. Another presented application refers to waterplane coefficient optimisation taking into account the added wave resistance at the stage of preliminary bulk carrier design.

  10. De brest à Aberdeen, la croisière 48 du Glomar Challenger From Brest to Aberdee, Glomar Challenger Sails on Leg 48

    Directory of Open Access Journals (Sweden)

    L'équipe Scientifique Embarquée

    2006-11-01

    Full Text Available La croisière 48 du Glomar Challenger s'est déroulée en 1976 entre Brest et Aberdeen sur la marge septentrionale du Golfe de Gascogne et le Banc de Rockall. Les sept sites forés ont permis de comparer la structure et l'histoire géologique de deux marges de types différents, formées par rifting, l'une dans une mer épicontinentale, l'autre dans un craton. L'histoire de la subsidence a pu être établie. De nombreux hiatus ont été mis en évidence dans les séries déposées en mer profonde, dont certains sont contemporains d'événements connus sur le plateau continental. Des marnes noires riches en matière organique d'origine détritique ont été trouvées dans le golfe de Gascogne. Elles ont pu se déposer aussi bien en mer profonde que sur le plateau continental. Des mesures de paléomagnétisme, de flux de chaleur et des diagraphies ont été effectuées avec succès. Leg 48 by the Glomar Challenger took place in 1976, between Brest and Aberdeen, on the northern margin of the Bay of Biscay and the Rockall Bank. The seven drilling sites enabled a comparison ta be made of the structure and geological history of two different types of margins, both formed by rifting, one in an epicontinental sea and the other in a craton. The history of subsidence was determined. A great many gaps were revealed in the series deposited in deep water, including some that are contemporary with events known on the continental shelf. Blackshales rich in organic motter of detrital origin were found in the Bay of Biscay. They may have been deposited either in deep water or on the continental shelf. Successful paleomagnetism and heat flow measurements were made, along with well logging.

  11. Buoyed by a Rising Tide: Information Literacy Sails into the Curriculum on the Currents of Evidence-Based Medicine and Professional Competency Objectives.

    Science.gov (United States)

    Kaplan, Richard B.; Whelan, Julia S.

    2002-01-01

    Discusses how information literacy efforts at the Massachusetts College of Pharmacy and Health Sciences have been supported by national trends within health science education to incorporate evidence-based medicine and problem-based learning into the curriculum. Describes effects on librarians, including requests for more instruction, creating…

  12. The Age of Sail: A Time When the Fortunes of Nations and Lives of Seamen Literally Turned With the Winds Their Ships Encountered at Sea

    Science.gov (United States)

    2010-01-01

    burdened weight of 368 tons. The HMS Beagle , captained by James FitzRoy during its famous 1831 to 1836 voyage on which Charles Darwin served as the ship’s...captain to manoeuvre his ship through narrow inlets and channels , or along kilo- metres of rugged coastline, while dealing with such problems as strong...after waiting for weeks in Plymouth, England, for favourable weather, the HMS Beagle set out on its historic five-year journey around the world

  13. Selection of cooling fluid for an organic Rankine cycle unit recovering heat on a container ship sailing in the Arctic region

    DEFF Research Database (Denmark)

    Suárez de la Fuente, Santiago; Larsen, Ulrik; Pierobon, Leonardo

    2017-01-01

    air as coolant. This paper explores the use of two different coolants, air and seawater, for an organic Rankine cycle (ORC) unit using the available waste heat in the scavenge air system of a container ship navigating in Arctic Circle. Using a two-step single objective optimisation process, detailed...

  14. Knack knots you need step-by-step instructions for more than 100 of the best sailing, fishing, climbing, camping and decorative knots

    CERN Document Server

    Tilton, Buck

    2008-01-01

    Untie the mystery of knot-making with this clever and handy guide. This new compendium presents all the knots you need to know, with brightly colored photographs enabling you to easily follow the instructions. In addition, the book includes copious information on using knots in most popular activities. With its clear step-by-step instructions and friendly tone, this is the one volume you can count on to guide you toward quick success in knot-making.

  15. Does renewable energy in Spain still have wind in its sails?;En Espagne, les energies renouvelables ont-elles toujours le vent (et le soleil) en poupe?

    Energy Technology Data Exchange (ETDEWEB)

    Vial, Th. [Ambassade de France en Espagne, Chef de pole, Mission economique-Ubifrance (Spain); Molenat, G. [Ambassade de France en Espagne, Service pour la Science et la technologie (Spain)

    2009-11-15

    Spain is apparently contradictory. It figures among the European countries farthest from the Kyoto Protocol's objectives but is often cited as an example, even by President Obama, for its success in speeding up developments in renewable energy. Successes in solar and wind power have proven that Spanish industry can, with support from the state and within a decade, develop to become competitive internationally at the very time when climate change will be having repercussions on economic models and opening new markets. From this vantage point, big projects (like the Mediterranean Solar Plan or future European Union initiatives related to the Energy-Climate package) should stimulate the Spanish, who will probably soon be looking for European partners. Given its advantages in wind and solar energy, the country should be able to consolidate an efficient energy solution with a promising future, while reinforcing its particularly innovative industry. (authors)

  16. Main: SAD201 [AT Atlas

    Lifescience Database Archive (English)

    Full Text Available method Diversification of protein structural analysis technologies by the SAIL method Masatsune Kainosho Graduate School of Science, Nagoya University SAD201.csml ... ...SAD201 SAD2 Diversification of protein structural analysis technologies by the SAIL

  17. Non-linear Structural Analysis of the Folding Process in a Deployable System for Satellites

    DEFF Research Database (Denmark)

    Lauridsen, Peter Riddersholm; Nikolajsen, Jan Ánike; Kristensen, Anders Schmidt

    2017-01-01

    Structural analysis of a sail solution1 to deorbit satellites is presented in this paper. The deployable drag sail consists of a circular highly flexible frame, sail and housing. The folding process of the highly flexible frame is complex and is only possible to describe analytical2 without a sai...

  18. 33 CFR 100.701 - Special Local Regulations; Marine Events in the Seventh Coast Guard District

    Science.gov (United States)

    2010-07-01

    ... Foundation Ortega River Race Course, Jacksonville; between Timuquana and Roosevelt Bridges. March or April...—3rd weekend Rolex Miami Olympic Sailing Race U.S. Sailing & U.S. Olympic Sailing Center Southern... than 500 feet from each vessel. March—1st week, Monday-Friday Bacardi Cup Biscayne Bay Star Fleet All...

  19. SPORTSKO JEDRENJE U CRNOJ GORI - TRADICIJA, SADAŠNJOST I PERSPEKTIVA

    Directory of Open Access Journals (Sweden)

    Božidar Petričeić

    2005-04-01

    Full Text Available The navigation, as a predecessor of a sailing sport, all-round here had a big tradition and a deep root too. The oldest written document on those activities date from the beginning of the last Millenium. From its very first steps, in a certain way a navigator’s rivalry, how to arrive before the others, was present, and with a time flow that fact becomes more and more important. The sailing, as an Olympic and an internationally recognized sport in Montenegro were organized in the Year 1948. In that time from 4 sailing clubs in the Boka KotorskaBay it was formed the Maritime Alliance of Montenegro, been renamed later into the Sailing Alliance of Montenegro. From its start our sailing alliance through the National Sailing Federation, now the SF of the State Community Serbia & Montenegro it has been incorporated in the International Sailing Federation (ISAF. The actual situation in the Montenegrin sailing sport characterizes an arising number of the sailing clubs, and now there are 10 of them. But, there is also a diminution of the number of the classes of the sport sailing boats. Now, in official use we have the Optimist, Laser, Star and the Cruiser class. Lately, the number of the Optimist class boats is in augmentation, which allow for more young kids to sail. Development of the sailing sport in Montenegro should be conducted simultaneously in a few directions. One of them is that the sailing clubs must be supported to their activities for own roomy, infrastructural and financial progress, with a purpose to improve proper sport work. A better perspective of a sailing sport also could be made with appropriate changes of a Race system (Match Race Regattas etc, and that is not all what could be done. It’s very important, for the better perspective of a sailing sport in Montenegro, should build a very suitable National Sailing – Nautical Center. Realization of this initiative, which unfortunately goes quite slowly, would give a strong impulse

  20. A prediction method of ice breaking resistance using a multiple regression analysis

    OpenAIRE

    Cho, Seong-Rak; Lee, Sungsu

    2015-01-01

    The two most important tasks of icebreakers are first to secure a sailing route by breaking the thick sea ice and second to sail efficiently herself for purposes of exploration and transportation in the polar seas. The resistance of icebreakers is a priority factor at the preliminary design stage; not only must their sailing efficiency be satisfied, but the design of the propulsion system will be directly affected. Therefore, the performance of icebreakers must be accura-tely calculated and e...

  1. In-Space Propulsion (346620) Technology Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Technologies include, but are not limited to, electric and advanced chemical propulsion, propellantless propulsion such as aerocapture and solar sails, sample return...

  2. Near Earth Asteroid Scout Thrust and Torque Model

    Science.gov (United States)

    Heaton, Andrew; Ahmad, Naeem; Miller, Kyle

    2017-01-01

    The Near Earth Asteroid (NEA) Scout is a solar sail mission whose objective is to scout at least one Near Earth Asteroid in preparation for manned missions to asteroids. NEA Scout will use a solar sail as the primary means of propulsion. Thus it is important for mission planning to accurately characterize the thrust of the sail. Additionally, the solar sail creates a relatively large solar disturbance torque that must be mitigated. For early mission design studies a flat plate model of the solar sail with a fixed center of pressure was adequate, but as mission concepts and the sail design matured, greater fidelity was required. Here we discuss the progress to a three-dimensional sail model that includes the effects of tension and thermal deformation that has been derived from a large structural Finite Element Model (FEM) developed by the Langley Research Center. We have found that the deformed sail membrane affects torque relatively much more than thrust. We have also found that other than uncertainty over the precise shape, the effect of small (approximately millimeter scale) wrinkles on the diffusivity of the sail is the leading remaining source of uncertainty. We demonstrate that millimeter-scale wrinkles can be modeled analytically as a change in the fraction of specular reflection. Finally we discuss the implications of these results for the NEA Scout mission.

  3. The aero- and hydromechanics of keel yachts

    CERN Document Server

    Slooff, J W

    2015-01-01

    How and why does sail boat performance depend on the configuration and trim of boat and sails? This book provides the yachtsman with answers in a relatively straightforward account of the physical mechanisms of sailing. It presents an accessible overview of the fluid dynamic aspects of sailing and sailing technology, addressing both aeromechanics and hydromechanics.  Readers are provided with the basic principles of physics and general mechanics that will assist their understanding of the fluid mechanics of sailing yachts. Rich appendices cover not only in-depth, mathematical-physical treatments and derivations for those wishing to explore further, but also helpful summaries of basic mathematical notions for those wishing to refresh their knowledge.  This work explores keel yachts, specifically single-masted mono-hulls with ‘fore-and-aft’, Bermuda-rigged sails. However, much of it is applicable to other types of sailing vessels such as multi-hulls, yachts with multiple masts, windsurf boards and the li...

  4. 76 FR 30236 - Requested Administrative Waiver of the Coastwise Trade Laws

    Science.gov (United States)

    2011-05-24

    ... comments electronically via the Internet at http://www.regulations.gov . All comments will become part of... weeks (one week per charter) as a team building/sailing school for teenagers. This would be the only sailing school to offer teenagers the possibility of learning how to handle a 46' catamaran in one week...

  5. The Coast Artillery Journal. Volume 73, Number 3, September 1930

    Science.gov (United States)

    1930-09-01

    2nd Lieut. G. E. Keeler, Jr., 62nd, Fort Totten, to Panama, sailing New York, October 23. 2nd Lieut. P. A. Roy , Lewiston, Maine, to Hawaii, sailing...ARTILLERY JOURNAL A Saga of the Sword. By F. Britten Austin. New York: Macmillan Company. 1929. $2.50. Grey Maiden. By A. D. H. Smith. New YQrk

  6. What Colour Is a Polar Bear's Skin?

    Science.gov (United States)

    Truchot, Sandrine; Weber, Agathe

    2005-01-01

    The association "Participe Futur", based in France, has set up a fantastic sailing and educational adventure with the help of the International Polar Foundation. A group of scientists left the South of France on 20 March 2005 on a sailing boat named "Alcyon". They will be on board for nine months, travelling all the way from…

  7. The World in the Viking Age

    DEFF Research Database (Denmark)

    The Viking Age was ignited by the art of building seaworthy sailing ships and the skills to sail them on the open sea. The growth in seafaring, trade, piracy, and exploration that began to gather momentum during the 8th century CE was not limited to Europe’s northern seas, however. Ships, laden...

  8. Experimental Investigation into the Aerodynamic Performance of Both Rigid and Flexible Wing Structured Micro-Air-Vehicles

    Science.gov (United States)

    2004-03-01

    aircraft. James McMichael, DARPA’s MAV Program Manager uniquely described the MAV concept as: MAVs should be thought of as aerial robots , as six-degree... Sailboats use the adaptive washout technique to aid control of the sail through twist of the sail edge normal to the relative wind (Waszak and Jenkins

  9. Dicty_cDB: Contig-U10767-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 782 ) CHCM1337.b1_B23.ab1 CHC(LMS) Texas blueweed Helia... 36 0.091 3 ( EK104349 ) 1092963037980 Global-Ocea...76306 ) SAIL_252b_B08.v1 SAIL Collection Arabidopsis thal... 48 1.1 1 ( EL412948 ) CHCL10521.b1_B15.ab1 CHC(LMS) Texas

  10. 46 CFR Exhibit No. 1 to Subpart Q... - Application for Refund or Waiver of Freight Charges Due to Tariff or Quoting Error

    Science.gov (United States)

    2010-10-01

    ... shipment(s). (g) Name of carrier and date shown on bill of lading (furnish legible copies of bill(s) of...) Amount of freight charges actually collected (furnish legible copies of rated bill(s) of lading or... shipments. (d)(1) Date(s) of receipt of shipment(s) by the carrier; (2) Date(s) of sailing(s) (furnish...

  11. The art of rigging

    CERN Document Server

    Biddlecombe, George

    1990-01-01

    The best manual ever produced on rigging a sailing ship, based on extensively revised and updated 1848 edition prepared by Biddlecombe, Master in the Royal Navy. Complete definition of terms, on-shore operations, process of rigging ships, reeving the running rigging and bending sails, rigging brigs, yachts and small vessels, more. 17 plates.

  12. The World in the Viking Age

    DEFF Research Database (Denmark)

    The Viking Age was ignited by the art of building seaworthy sailing ships and the skills to sail them on the open sea. The growth in seafaring, trade, piracy, and exploration that began to gather momentum during the 8th century CE was not limited to Europe’s northern seas, however. Ships, laden w...

  13. Slide 20

    Indian Academy of Sciences (India)

    “Twenty years from now you will be more disappointed by the things you didn't do than by the ones you did do. So throw off your bowlines. Sail away from the safe harbor. Catch the trade winds in your sails.

  14. Solving the heliogyro’s inverse problem

    NARCIS (Netherlands)

    Heiligers, M.J.; Guerrant, D.; Lawrence, D

    2016-01-01

    A heliogyro is a solar sail concept that divides the solar sail membrane into a number of long, slender blades of film extended from a central hub, maintained in a flat state through spin-induced tension. The heliogyro can redirect and scale the solar radiation pressure (SRP) force and can achieve

  15. 46 CFR 169.101 - Purpose.

    Science.gov (United States)

    2010-10-01

    ..., DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS General Provisions § 169.101 Purpose. The regulations in this part set forth uniform requirements which are suited to the particular characteristics and specialized operations of sailing school vessels as defined in Title 46...

  16. Optimal Speed Control for Cruising

    DEFF Research Database (Denmark)

    Blanke, M.

    1994-01-01

    With small profit margins in merchant shipping and more than eighty percent of sailing time being cross ocean voyages, speed control is crucial for vessel profitability......With small profit margins in merchant shipping and more than eighty percent of sailing time being cross ocean voyages, speed control is crucial for vessel profitability...

  17. Physical model of kitesurfing

    Science.gov (United States)

    Zimoch, Pawel; Paxson, Adam; Obropta, Edward; Peleg, Tom; Parker, Sam; Hosoi, A. E.

    2013-11-01

    Kitesurfing is a popular water sport, similar to windsurfing, utilizing a surfboard-like platform pulled by a large kite operated by the surfer. While the kite generates thrust that propels the surfer across the water, much like a traditional sail, it is also capable of generating vertical forces on the surfer, reducing the hydrodynamic lift generated by the surfboard required to support the surfer's weight. This in turn reduces drag acting on the surfboard, making sailing possible in winds lower than required by other sailing sports. We describe aerodynamic and hydrodynamic models for the forces acting on the kite and the surfboard, and couple them while considering the kite's position in space and the requirement for the kite to support its own weight. We then use these models to quantitatively characterize the significance of the vertical force component generated by the kite on sailing performance (the magnitude of achievable steady-state velocities and the range of headings, relative to the true wind direction, in which sailing is possible), and the degradation in sailing performance with decreasing wind speeds. Finally, we identify the areas of kite and surfboard design whose development could have the greatest impact on improving sailing performance in low wind conditions.

  18. One analysis of aerodynamic characteristics of sloop rig; Sloop rig no kuriki tokusei no ichikaiseki

    Energy Technology Data Exchange (ETDEWEB)

    Shinkai, A.; Iyoda, H. [Kyushu University, Fukuoka (Japan). Faculty of Engineering

    1996-10-01

    A sloop which is one form of rigs of sail boats was analyzed of its basic aerodynamic characteristics by using the vortex distribution method. This solution method consists of an algorithm to derive a given pressure distribution on thin sail surface based on the vortex distribution method, and an algorithm to derive sail shapes from the given pressure distribution under a hypothesis of using flexible thin sails. An example of the calculation results showed distribution in an angular distance of pressure difference coefficients which act on each of the two sails, and showed the case where trim angle is changed and seven other parameters are fixed. With respect to control of trim angle which has close correlation with basic performance of the sloop rig, how the increase in the trim angle releases the main sail from aerodynamically adverse effect to which the main sail is subjected was shown. Furthermore, in order to estimate simply the performance of the sloop rig, a series calculation was executed and a chart was prepared which can estimate simply how a maximum thrust can be generated. 17 refs., 12 figs., 1 tab.

  19. Attitude-error compensation for airborne down-looking synthetic-aperture imaging lidar

    Science.gov (United States)

    Li, Guang-yuan; Sun, Jian-feng; Zhou, Yu; Lu, Zhi-yong; Zhang, Guo; Cai, Guang-yu; Liu, Li-ren

    2017-11-01

    Target-coordinate transformation in the lidar spot of the down-looking synthetic-aperture imaging lidar (SAIL) was performed, and the attitude errors were deduced in the process of imaging, according to the principle of the airborne down-looking SAIL. The influence of the attitude errors on the imaging quality was analyzed theoretically. A compensation method for the attitude errors was proposed and theoretically verified. An airborne down-looking SAIL experiment was performed and yielded the same results. A point-by-point error-compensation method for solving the azimuthal-direction space-dependent attitude errors was also proposed.

  20. Mitigating Climate Change with Earth Orbital Sunshades

    Science.gov (United States)

    Coverstone, Victoria; Johnson, Les

    2015-01-01

    An array of rotating sunshades based on emerging solar sail technology will be deployed in a novel Earth orbit to provide near-continuous partial shading of the Earth, reducing the heat input to the atmosphere by blocking a small percentage of the incoming sunlight, and mitigating local weather effects of anticipated climate change over the next century. The technology will provide local cooling relief during extreme heat events (and heating relief during extreme cold events) thereby saving human lives, agriculture, livestock, water and energy needs. A synthesis of the solar sail design, the sails' operational modes, and the selected orbit combine to provide local weather modification.

  1. 77 FR 16838 - Notice of Agreements Filed

    Science.gov (United States)

    2012-03-22

    ... Sailing Agreement. Parties: Dole Ocean Cargo Express, Inc. and Great White Fleet (US) Ltd. Filing Party... name of Great White Fleet (US) Ltd. to Great White Fleet Liner Services Ltd. Agreement No.: 011961-011...

  2. 46 CFR 173.058 - Double bottom requirements.

    Science.gov (United States)

    2010-10-01

    ... PERTAINING TO VESSEL USE School Ships § 173.058 Double bottom requirements. Each new sailing school vessel... service must comply with the double bottom requirements in §§ 171.105 through 171.109, inclusive, of this...

  3. Pop / Lauri Tikerpe

    Index Scriptorium Estoniae

    Tikerpe, Lauri

    2007-01-01

    Heliplaatidest: Laurent Garnier, Bugge Wesseltoft, Philippe Nadaud, Benjamin Rippert "Public Out Burst", Enthroned "Tetra Karcist", Bruce Springsteen with the Sessions Band "Live in Dublin", Tuxedomoon "Vapour Trails", Atreyu "Lead Sails Paper Anchor", Still Remains "The Serpent"

  4. High Power Orbit Transfer Vehicle

    National Research Council Canada - National Science Library

    Gulczinski, Frank

    2003-01-01

    ... from Virginia Tech University and Aerophysics, Inc. to examine propulsion requirements for a high-power orbit transfer vehicle using thin-film voltaic solar array technologies under development by the Space Vehicles Directorate (dubbed PowerSail...

  5. Project CHECO Southeast Asia Report. Aerial Protection of Mekong River Convoys in Cambodia

    National Research Council Canada - National Science Library

    Mitchell, William A

    1971-01-01

    ...) shortages in the Khmer Republic (Cambodia) which had resulted from successful enemy attacks on commercial shipping vessels sailing the Mekong River inside Cambodia These attacks, combined with the closure of land Route 4 from the port city...

  6. 78 FR 30388 - Requested Administrative Waiver of the Coastwise Trade Laws: Vessel SAFARI; Invitation for Public...

    Science.gov (United States)

    2013-05-22

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF TRANSPORTATION Maritime Administration Requested Administrative Waiver of the Coastwise Trade Laws: Vessel SAFARI... of the vessel SAFARI is: Intended Commercial Use Of Vessel: ``Sailing charters, tourism''. Geographic...

  7. EX1204: Northeastern Canyons and Continental Margins Exploration on NOAA Ship Okeanos Explorer between 20120529 and 20120613

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — During the Okeanos Explorer (EX) mission EX1204, the vessel will sail from Norfolk, VA, along the continental shelf break of the U.S. East Coast from Virginia to...

  8. Stone anchors from Mombasa, Kenya: Evidence of maritime contacts with Indian Ocean countries

    Digital Repository Service at National Institute of Oceanography (India)

    Bita, C.; Tripati, S.

    of technology and barter of products. This facilitated sailing over long distances, crossing the Red sea, the Persian Gulf and the Indian Ocean. Among other ancient coastal cities on the East African Coast, Mombasa has played a significant role...

  9. Vic-Maui Race Observed Marine Debris Map Service, Pacific Ocean, 2012, US EPA Region 9

    Data.gov (United States)

    U.S. Environmental Protection Agency — Location and descriptions of marine debris observed by the Sailing Vessel (S/V) Family Affair yacht during the Victoria, British Columbia to Maui, Hawaii Yacht Race...

  10. Searching for artificial equilibrium points to place satellites "above and below" L3 in the Sun-Earth system

    Science.gov (United States)

    de Almeida, A. K., Jr.; Prado, A. F. B. A.; Sanchez, D. M.; Yokoyama, T.

    2017-10-01

    Regarding practical applications of L3 of the Sun-Earth system, there are few studies with the goal of placing a spacecraft at this point, or in orbit around it. One of the main problems in placing a spacecraft near this equilibrium point is the fact that it is located behind the Sun with respect to the Earth. The Sun would be blocking direct communication between the spacecraft and the Earth. The present research gives several options to solve this problem by using a solar sail to place one or two spacecraft above and/or below the Ecliptic plane. This sail could also be used for the mission itself, to collect energy or particles. By using an adequate size, location and attitude of the solar sail, the equilibrium point can be moved from its original location to allow communications between the spacecraft and the Earth. A preliminary study of a solar sail that uses this strategy is shown here.

  11. Rapid Advanced Heliocentric Mission Design for L3, L4, L5, NEO Rendezvous, Capture, Sample Return Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Provide fast, new capability for Loose SmallSat Constellation with solar sail and impulsive propulsion to nonlinear heliocentric orbits, high inclination, low energy...

  12. Time-stepped & discrete-event simulations of electromagnetic propulsion systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The existing plasma codes are ill suited for modeling of mixed resolution problems, such as the plasma sail, where the system under study comprises subsystems with...

  13. Changes in hydration status of elite Olympic class sailors in different climates and the effects of different fluid replacement beverages

    National Research Council Canada - National Science Library

    Lewis, Evan Jh; Fraser, Sarah J; Thomas, Scott G; Wells, Greg D

    2013-01-01

    Olympic class sailing poses physiological challenges similar to other endurance sports such as cycling or running, with sport specific challenges of limited access to nutrition and hydration during competition...

  14. Inland Waters - Mississippi River Centerline - Headwaters to Gulf Coast

    Data.gov (United States)

    Army Corps of Engineers, Department of the Army, Department of Defense — Mississippi River centerline data derived from USACE navigation sailing line (recommended track) data and on-screen digitized in areas of no data. Data set extends...

  15. Investigation of Factors Affecting Information Literacy Student Learning Outcomes Fails to Undercover Significant Findings. A Review of: Detlor, B., Julien, H., Willson, R., Serenko, A., & Lavallee, M. (2011). Learning outcomes of information literacy instruction at business schools. Journal of the American Society for Information Science and Technology, 62(3), 572-585

    National Research Council Canada - National Science Library

    Jason Martin

    2011-01-01

    ... – Three Canadian business schools.Subjects – Seven librarians, 4 library administrators, 16 business faculty, and 52 undergraduate business students were interviewed, and the Standardized Assessment of Information Literacy Skills (SAILS...

  16. 76 FR 29989 - National Maritime Day, 2011

    Science.gov (United States)

    2011-05-24

    ... maritime trade was booming, fostering exchanges across the world and aiding our military at war. During... all ships sailing under the American flag dress ship on that day. ] IN WITNESS WHEREOF, I have...

  17. Looking back : The art of drawing

    NARCIS (Netherlands)

    Hilkhuijsen, J.

    2008-01-01

    The artistic component of design theory at Delft University of Technology is based on a strong tradition, greatly enhanced by efforts of teachers such as Paul Tetar van Elven and Bram Gips. It hasnt always been plain sailing, though.

  18. From Boffing to Body Flying, UCSC Students Are Discovering the Joys of New Athletics

    Science.gov (United States)

    College and University Business, 1973

    1973-01-01

    The new athletic program at the University of California, Santa Cruz, is designed to provide noncompetitive, nonspectator physical activities and recreational opportunities, including jogging, sailing, mountaineering, aikido, backpacking, kayaking and body flying. (Author/PG)

  19. 76 FR 34992 - Notice of Agreements Filed

    Science.gov (United States)

    2011-06-15

    ....gov . Agreement No.: 012093-001. Title: CSAV/K-Line Space Charter and Sailing Agreement. Parties... geographic scope of the Agreement and changes the Agreement's name. Agreement No.: 201211. Title: Marine...

  20. 76 FR 40911 - Notice of Agreements Filed

    Science.gov (United States)

    2011-07-12

    ....gov . Agreement No.: 012093-001. Title: CSAV/K-Line Space Charter and Sailing Agreement. Parties... geographic scope of the Agreement and changes the Agreement's name. Agreement No.: 201211. Title: Marine...

  1. 77 FR 25649 - Special Local Regulations for Marine Events; Patuxent River, Solomons, MD

    Science.gov (United States)

    2012-05-01

    ... this proposed rule to be so minimal that a full Regulatory Evaluation under the regulatory policies and... includes but is not limited to sail boat regattas, boat parades, power boat racing, swimming events, crew...

  2. 77 FR 35266 - Special Local Regulation for Marine Events, Chesapeake Bay Workboat Race, Back River, Messick...

    Science.gov (United States)

    2012-06-13

    ... that a full Regulatory Evaluation is unnecessary. Although this rule prevents traffic from transiting a... includes but is not limited to sail boat regattas, boat parades, power boat racing, swimming events, crew...

  3. BOREAS TE-18 Geosail Canopy Reflectance Model

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: The GEOSAIL model was created by combining the SAIL (Scattering from Arbitrarily Inclined Leaves) model with the Jasinski geometric model to simulate...

  4. 46 CFR 166.05 - Course of study for deck students.

    Science.gov (United States)

    2010-10-01

    ... equip the student fully with the theoretical knowledge required for the proper discharge of the duties... the sailing and management of a vessel insofar as such operations form a part of the duties of able...

  5. 46 CFR 166.10 - Course of study for engineering students.

    Science.gov (United States)

    2010-10-01

    ... student with the theoretical knowledge required for the proper discharge of the duties developing upon... operations incident to the sailing and management of a vessel insofar as such operations form a part of the...

  6. 33 CFR 83.06 - Safe speed (Rule 6).

    Science.gov (United States)

    2010-07-01

    ... NAVIGATION RULES RULES Steering and Sailing Rules Conduct of Vessels in Any Condition of Visibility § 83.06... interference; (4) The possibility that small vessels, ice and other floating objects may not be detected by...

  7. The Great adventure

    National Research Council Canada - National Science Library

    Lemire, J; Plantanida, T; Suzuki, D

    2003-01-01

    .... We watch as the crew navigate a three-masted sailing ship through the legendary Northwest Passage - a treacherous, ice-choked route that has captured the imaginations of great explores for centuries...

  8. 48 CFR 52.247-51 - Evaluation of Export Offers.

    Science.gov (United States)

    2010-10-01

    ... available sailings on U.S.-flag vessels, and other pertinent transportation factors, it determines that use... scheduled in this provision for delivery during the ice-free or navigable period as proclaimed by the...

  9. 77 FR 13695 - Requested Administrative Waiver of the Coastwise Trade Laws: Vessel IN THE SHELTER; Invitation...

    Science.gov (United States)

    2012-03-07

    ... comments electronically via the Internet at http://www.regulations.gov . All comments will become part of... classes from Basic Keelboat through Bareboat Cruising, with all sailing classes being certified through US...

  10. 77 FR 13696 - Requested Administrative Waiver of the Coastwise Trade Laws: Vessel SIREN; Invitation for Public...

    Science.gov (United States)

    2012-03-07

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF TRANSPORTATION Maritime Administration Requested Administrative Waiver of the Coastwise Trade Laws: Vessel SIREN... the vessel SIREN is: Intended Commercial Use Of Vessel: ``Sailing charters.'' Geographic Region...

  11. Joseph Needham, CH, FRS, FBA., b. 9 December 1900; d. 24 April 1995. A Sailor's Tribute and a Memoir

    Science.gov (United States)

    Waters, D. W.

    Sailors, indeed anyone interested in the development of sailing craft, will be for ever indebted to Joseph Needham. Today they will find with ease literature that describes the origins, characteristics, and development of sailing craft in the various regions of the world; the inter-relationships between natural products, and native hull stuctures and forms, sails' fabrics, shapes, and performance. They can learn, too, that the closestowing anchor, the water-tight bulkhead, the balanced rudder (and other features of the modern efficiency-conscious ship constructor) have all been adapted from the millenniaold, so-long-despised by Westerners, Chinese junk, just as has, late in this twentieth century, the stiffened sail of the modern high-performance yacht.

  12. Oceanographic temperature profiles from the HMS CHALLENGER in the Antarctic, North Atlantic and other locations from 1873-02-15 to 1876-05-06 (NODC Accession 0126754)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — From 1872 to 1876, the HMS Challenger sailed around the world studying ocean features such as ocean temperature and chemistry, wildlife, and sounding the ocean,...

  13. NASA's Near Earth Asteroid Scout Mission

    Science.gov (United States)

    Johnson, Les; McNutt, Leslie; Castillo-Rogez, Julie

    2017-01-01

    NASA is developing solar sail propulsion for a near-term Near Earth Asteroid (NEA) reconnaissance mission and laying the groundwork for their future use in deep space science and exploration missions. The NEA Scout mission, funded by NASA's Advanced Exploration Systems Program and managed by NASA MSFC, will use the sail as primary propulsion allowing it to survey and image one or more NEA's of interest for possible future human exploration. NEA Scout uses a 6U cubesat (to be provided by NASA's Jet Propulsion Laboratory), an 86 m2 solar sail and will weigh less than 14 kilograms. The solar sail for NEA Scout will be based on the technology developed and flown by the NASA NanoSail-D and The Planetary Society's Lightsail-A. Four 7 m stainless steel booms wrapped on two spools (two overlapping booms per spool) will be motor deployed and pull the sail from its stowed volume. The sail material is an aluminized polyimide approximately 3 microns thick. NEA Scout will launch on the Space Launch System (SLS) first mission in 2018 and deploy from the SLS after the Orion spacecraft is separated from the SLS upper stage. The NEA Scout spacecraft will stabilize its orientation after ejection using an onboard cold-gas thruster system. The same system provides the vehicle Delta-V sufficient for a lunar flyby. After its first encounter with the moon, the 86 m2 sail will deploy, and the sail characterization phase will begin. A mechanical Active Mass Translation (AMT) system, combined with the remaining ACS propellant, will be used for sail momentum management. Once the system is checked out, the spacecraft will perform a series of lunar flybys until it achieves optimum departure trajectory to the target asteroid. The spacecraft will then begin its two year-long cruise. About one month before the asteroid flyby, NEA Scout will pause to search for the target and start its approach phase using a combination of radio tracking and optical navigation. The solar sail will provide

  14. Proceedings of the Annual U.S. Army Operations Research Symposium (13th) , AORS XIII, Held at Fort Lee, Virginia on 29 October - 1 November 1974, Co- Hosted by Army Logistics Center, Fort Lee, Virginia and Army Quartermaster Center and Fort Lee, Virginia. Volume 1

    Science.gov (United States)

    1974-11-01

    Edgar B. Vandiver, III Research Analyst Office of the Deputy Under Secretary of the Army (Operations Research) 11 G Special Activity COL Louis F...my coauthors, Mr. Frank Paca, Chief of the Camouflage Effectiveness Assessment Office and Mr. Allan Sylvester of the Countersurveillance and...time-to-scheduled sailings. Other DSS study results show that vans are held at the POE waiting for ship sailings. It is obvious that by holding

  15. Does the MRAP Meet the US Army’s Needs as the Primary Method of Protecting Troops from the IED Threat?

    Science.gov (United States)

    2009-06-12

    They often jammed frequencies used to control bomb-disposal robots . This left troops with the choice of being able to communicate or being...When EOD arrives, they will most likely send a TALON robot , which they remotely control from inside the protection of their vehicle. The TALON...square inch blast effect. Another example of this is the sail on a sailboat . If the sail is down, even in a strong wind there is little effect on

  16. Conduction Electrohydrodynamics with Mobile Electrodes: A Novel Actuation System for Untethered Robots

    OpenAIRE

    Cacucciolo, Vito; Shigemune, Hiroki; Cianchetti, Matteo; Laschi, Cecilia; Maeda, Shingo

    2017-01-01

    Electrohydrodynamics (EHD) refers to the direct conversion of electrical energy into mechanical energy of a fluid. Through the use of mobile electrodes, this principle is exploited in a novel fashion for designing and testing a millimeter?scale untethered robot, which is powered harvesting the energy from an external electric field. The robot is designed as an inverted sail?boat, with the thrust generated on the sail submerged in the liquid. The diffusion constant of the robot is experimental...

  17. "Governare il diabete" ("to steer diabetes"): a new proposal for diabetic camps.

    Science.gov (United States)

    Salvatoni, Alessandro; Pompili, Valeria; Biasoli, Roberta; Cardani, Roberta; Arioli, Gianluigi; Nespoli, Luigi

    2003-01-01

    "Governare il diabete" (the Italian translation of "to steer diabetes") is a project which gives young diabetics the opportunity of sailing with non-diabetic companions in a protected and educational environment. The education technique, based on the parallelism between sailing and diabetes, encourage correct self-management of both diabetes related and unrelated problems. The impact of the experience on self-esteem, quality of life and metabolic control is currently under investigation.

  18. Jørn Utzon’s Maritime Origins

    DEFF Research Database (Denmark)

    Jaeger, Thomas Arvid

    2014-01-01

    Article about Jørn Utzons and the influence on his architecture comming from his early years with sailing, and learning about boat construction and the design principles from his father - the yacht designer Aage Utzon.......Article about Jørn Utzons and the influence on his architecture comming from his early years with sailing, and learning about boat construction and the design principles from his father - the yacht designer Aage Utzon....

  19. Dicty_cDB: Contig-U15239-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available rain ... 54 2e-04 2 ( ES520208 ) BIG_AF_26362 Brine Shrimp embryos, 15 hours afte...r... 48 4e-04 2 ( ES522873 ) BIG_AF_30693 Brine Shrimp embryos, 15 hours after... 48 4e-04 2 ( EK201674 ) 10..... 48 1.1 1 ( CL478285 ) SAIL_287_B02.v1 SAIL Collection Arabidopsis thali... 48 1.1 1 ( ES508460 ) BIG_AF_16277 Brine

  20. Prox-1 Automated Proximity Operations

    Science.gov (United States)

    2016-01-13

    on demonstrating the functionality required to meet minimum mission success criteria. The minimum mission includes on- orbit spacecraft checkout of...also includes deployment of LightSail-B from the P-POD, and imaging of LightSail-B for 20 minutes as it recedes from Prox-1. small satellite ; proximity...criteria. The minimum mission includes on- orbit spacecraft checkout of all spacecraft subsystems, including flight qualification of the following new

  1. Toward 'socially constructive' social constructions of leadership

    OpenAIRE

    Grint, Keith; Jackson, Brad

    2010-01-01

    In their introductory editorial essay for this special issue, David Grant and Gail Fairhurst have done us a great service by valiantly producing a "Sailing Guide" to the Social Construction of Leadership (Fairhurst & Grant, 2010). As with rounding the Capes, this is not a task for the faint of heart. A sailing guide is designed to provide vital knowledge about a particular sea or coast, providing us with charts, warnings about potential hazards and an indication where we might find safe haven...

  2. Artificial intelligence programming languages for computer aided manufacturing

    Science.gov (United States)

    Rieger, C.; Samet, H.; Rosenberg, J.

    1979-01-01

    Eight Artificial Intelligence programming languages (SAIL, LISP, MICROPLANNER, CONNIVER, MLISP, POP-2, AL, and QLISP) are presented and surveyed, with examples of their use in an automated shop environment. Control structures are compared, and distinctive features of each language are highlighted. A simple programming task is used to illustrate programs in SAIL, LISP, MICROPLANNER, and CONNIVER. The report assumes reader knowledge of programming concepts, but not necessarily of the languages surveyed.

  3. Precursor missions to interstellar exploration.

    Science.gov (United States)

    Wallace, R. A.

    This paper summarizes material developed over a three-month period by a JPL team of mission architects/analysts and advanced technology developers for presentation to NASA Headquarters in the summer of 1998. A preliminary mission roadmap is suggested that leads to the exploration of star systems within 40 light years of our Solar System. The precursor missions include technology demonstrations as well as missions that return significant new knowledge about the space environment reached. Three propulsion technology candidates are selected on the basis of allowing eventual travel to the nearest star taking 10 years. One of the three propulsion technologies has a near term version applicable to early missions (prior to 2010) - the solar sail. Using early sail missions other critical supporting technologies can be developed that will later enable Interstellar travel. Example precursor missions are sail demonstration missions, including a solar storm warning mission demonstrating a simple sail, a solar polar imaging mission using an intermediate sail, and a 200-AU Heliosphere Explorer mission using an advanced solar sail. Mission and technology strategy, science return, and potential mission spin-offs are described.

  4. Deployable Propulsion, Power and Communication Systems for Solar System Exploration

    Science.gov (United States)

    Johnson, Les; Carr, John A.; Boyd, Darren

    2017-01-01

    NASA is developing thin-film based, deployable propulsion, power, and communication systems for small spacecraft that could provide a revolutionary new capability allowing small spacecraft exploration of the solar system. By leveraging recent advancements in thin films, photovoltaics, and miniaturized electronics, new mission-level capabilities will be enabled aboard lower-cost small spacecraft instead of their more expensive, traditional counterparts, enabling a new generation of frequent, inexpensive deep space missions. Specifically, thin-film technologies are allowing the development and use of solar sails for propulsion, small, lightweight photovoltaics for power, and omnidirectional antennas for communication. Like their name implies, solar sails 'sail' by reflecting sunlight from a large, lightweight reflective material that resembles the sails of 17th and 18th century ships and modern sloops. Instead of wind, the sail and the ship derive their thrust by reflecting solar photons. Solar sail technology has been discussed in the literature for quite some time, but it is only since 2010 that sails have been proven to work in space. Thin-film photovoltaics are revolutionizing the terrestrial power generation market and have been found to be suitable for medium-term use in the space environment. When mounted on the thin-film substrate, these photovoltaics can be packaged into very small volumes and used to generate significant power for small spacecraft. Finally, embedded antennas are being developed that can be adhered to thin-film substrates to provide lightweight, omnidirectional UHF and X-band coverage, increasing bandwidth or effective communication ranges for small spacecraft. Taken together, they may enable a host of new deep space destinations to be reached by a generation of spacecraft smaller and more capable than ever before.

  5. Reliable and sensitive physical testing of elite trapeze sailors

    DEFF Research Database (Denmark)

    Bay, Jonathan; Bojsen-Møller, Jens; Nordsborg, Nikolai Baastrup

    2017-01-01

    was completed on four occasions to determine test reliability and sensitivity to manipulations in body-weight. Rope-pulling mean power output (MPO), oxygen consumption (VO2 ), heart rate (HR) and blood lactate values were acquired in all trials. In part 2, six sailors completed on-water racing with concurrent......It was investigated, if a newly developed discipline specific test for elite-level trapeze sailors is reli-able and sensitive. Furthermore, the physical demands of trapeze sailing were examined. In part 1, nine national team athletes were accustomed to a simulated sailing test, which subsequently....... 265 ± 45W, Pwater sailing was 54.5 ± 7.2% VO2max , 75.1 ± 3.1% HRmax and 5.8 ± 2.7 mM, respectively. However, VO2 and HR were substantially higher for periods of the race...

  6. Auditory learning: a developmental method.

    Science.gov (United States)

    Zhang, Yilu; Weng, Juyang; Hwang, Wey-Shiuan

    2005-05-01

    Motivated by the human autonomous development process from infancy to adulthood, we have built a robot that develops its cognitive and behavioral skills through real-time interactions with the environment. We call such a robot a developmental robot. In this paper, we present the theory and the architecture to implement a developmental robot and discuss the related techniques that address an array of challenging technical issues. As an application, experimental results on a real robot, self-organizing, autonomous, incremental learner (SAIL), are presented with emphasis on its audition perception and audition-related action generation. In particular, the SAIL robot conducts the auditory learning from unsegmented and unlabeled speech streams without any prior knowledge about the auditory signals, such as the designated language or the phoneme models. Neither available before learning starts are the actions that the robot is expected to perform. SAIL learns the auditory commands and the desired actions from physical contacts with the environment including the trainers.

  7. Design of a recovery system for a reentry vehicle

    Science.gov (United States)

    von Eckroth, Wulf; Garrard, William L.; Miller, Norman

    Engineers are often required to design decelerator systems which are deployed in cross-wind orientations. If the system is not designed to minimize 'line sail', damage to the parachutes could result. A Reentry Vehicle Analysis Code (RVAC) and an accompanying graphics animation software program (DISPLAY) are presented in this paper. These computer codes allow the user to quickly apply the Purvis line sail modeling technique to any vehicle and then observe the relative motion of the vehicle, nose cap, suspension lines, pilot and drogue bags and canopies on a computer screen. Data files are created which allow plots of velocities, spacial positions, and dynamic pressures versus time to be generated. The code is an important tool for the design engineer because it integrates two degrees of freedom (DOF) line sail equations with a three DOF model of the reentry body and jettisoned nose cap to provide an animated output.

  8. Qualitative and Quantitative Analysis of Congested Marine Traffic Environment – An Application Using Marine Traffic Simulation System

    Directory of Open Access Journals (Sweden)

    Kazuhiko Hasegawa

    2013-06-01

    Full Text Available Difficulty of sailing is quite subjective matter. It depends on various factors. Using Marine Traffic Simulation System (MTSS developed by Osaka University this challenging subject is discussed. In this system realistic traffic flow including collision avoidance manoeuvres can be reproduced in a given area. Simulation is done for southward of Tokyo Bay, Strait of Singapore and off-Shanghai area changing traffic volume from 5 or 50 to 150 or 200% of the present volume. As a result, strong proportional relation between near-miss ratio and traffic density per hour per sailed area is found, independent on traffic volume, area size and configuration. The quantitative evaluation index of the difficulty of sailing, here called risk rate of the area is defined using thus defined traffic density and near-miss ratio.

  9. Systems Engineering Metrics: Organizational Complexity and Product Quality Modeling

    Science.gov (United States)

    Mog, Robert A.

    1997-01-01

    Innovative organizational complexity and product quality models applicable to performance metrics for NASA-MSFC's Systems Analysis and Integration Laboratory (SAIL) missions and objectives are presented. An intensive research effort focuses on the synergistic combination of stochastic process modeling, nodal and spatial decomposition techniques, organizational and computational complexity, systems science and metrics, chaos, and proprietary statistical tools for accelerated risk assessment. This is followed by the development of a preliminary model, which is uniquely applicable and robust for quantitative purposes. Exercise of the preliminary model using a generic system hierarchy and the AXAF-I architectural hierarchy is provided. The Kendall test for positive dependence provides an initial verification and validation of the model. Finally, the research and development of the innovation is revisited, prior to peer review. This research and development effort results in near-term, measurable SAIL organizational and product quality methodologies, enhanced organizational risk assessment and evolutionary modeling results, and 91 improved statistical quantification of SAIL productivity interests.

  10. Design of a recovery system for a reentry vehicle

    Science.gov (United States)

    Von Eckroth, Wulf; Garrard, William L.; Miller, Norman

    1993-01-01

    Engineers are often required to design decelerator systems which are deployed in cross-wind orientations. If the system is not designed to minimize 'line sail', damage to the parachutes could result. A Reentry Vehicle Analysis Code (RVAC) and an accompanying graphics animation software program (DISPLAY) are presented in this paper. These computer codes allow the user to quickly apply the Purvis line sail modeling technique to any vehicle and then observe the relative motion of the vehicle, nose cap, suspension lines, pilot and drogue bags and canopies on a computer screen. Data files are created which allow plots of velocities, spacial positions, and dynamic pressures versus time to be generated. The code is an important tool for the design engineer because it integrates two degrees of freedom (DOF) line sail equations with a three DOF model of the reentry body and jettisoned nose cap to provide an animated output.

  11. A prediction method of ice breaking resistance using a multiple regression analysis

    Science.gov (United States)

    Cho, Seong-Rak; Lee, Sungsu

    2015-07-01

    The two most important tasks of icebreakers are first to secure a sailing route by breaking the thick sea ice and second to sail efficiently herself for purposes of exploration and transportation in the polar seas. The resistance of icebreakers is a priority factor at the preliminary design stage; not only must their sailing efficiency be satisfied, but the design of the propulsion system will be directly affected. Therefore, the performance of icebreakers must be accurately calculated and evaluated through the use of model tests in an ice tank before construction starts. In this paper, a new procedure is developed, based on model tests, to estimate a ship's ice breaking resistance during continuous ice-breaking in ice. Some of the factors associated with crushing failures are systematically considered in order to correctly estimate her ice-breaking resistance. This study is intended to contribute to the improvement of the techniques for ice resistance prediction with ice breaking ships.

  12. Factores determinantes del rendimiento en vela deportiva: revisión de la literatura

    OpenAIRE

    Aarón Manzanares Serrano; Francisco Segado Segado; Ruperto Menayo Antúnez

    2012-01-01

    Los objetivos del presente estudio han sido revisar, identificar y analizar las investigaciones que han indagado acerca de los factores influyentes en el rendimiento deportivo en vela y determinar cuáles de éstos son los de mayor relevancia. Se presentan los datos obtenidos a partir del análisis realizado sobre diez bases de datos, empleando como descriptores de búsqueda de artículos científicos las palabras "sail", "sailing" y "sailor". Se acotó la búsqueda a los trabajos que contenían dicha...

  13. Bol d'Or success for all-women crew from CERN

    CERN Multimedia

    2001-01-01

    The boat 'Mic Mac' and its CERN's all-woman crew (left to right), Christine Theurillat, Ursula Haenger , Paola Catapano, Petra Riedler, and skipper Cristina Morone. Spectacular highlight of the Lake Leman sailing calendar is the annual Bol d'Or race. Held this year on 16 and 17 June, the event attracted nearly 500 teams who competed under extreme weather conditions for the honours. Among the competitors was an all-woman crew from the CERN Yachting Club, sailing their Surprise boat, Mic Mac. The team was not only among the 397 boats to finish, but also the first all-woman crewed single hull boat to cross the line.

  14. Modelling of Structural Loads in Drag Augmented Space Debris Removal Concepts

    DEFF Research Database (Denmark)

    Kristensen, Anders Schmidt; Nikolajsen, Jan Ánike; Lauridsen, Peter Riddersholm

    2017-01-01

    A Self-deployable Deorbiting Space Structure (SDSS) is used for drag augmented space debris removal. A highly flexible frame allows for a folding of the structure by bifurcation. This research models the structural loads during the deployment and unfolding of the drag sail in Low Earth Orbit (LEO......). The Spacecraft travels with 7.8 km/s at deployment. As the drag sail unfolds instantaneously the structure must withstand the loads from the unfolding and the drag. Thermal loads are included in the FEA as the temperature varies from -80°C to +80°C during deorbit. The results are used to verify the structural...

  15. Enhancements in Photon Pressure Measurements Using a Solar Simulator

    Science.gov (United States)

    Gray, P. A.; Edwards, D. L.; Carruth, M. R., Jr.; Munafo, Paul (Technical Monitor)

    2001-01-01

    Initial proof of concept photon momentum measurements were reported at the AIAA Conference in Reno Nevada, January 8-11, 2001. That presentation verified that photon pressure on a simulated solar sail material can be measured under high vacuum conditions using a full spectrum solar simulator and a vacuum compatible force measurement system. Modifications to this test system were implemented to enhance the accuracy of the photon pressure measurement. This paper describes the photon pressure measurement technique and modifications to increase the measurement accuracy using a candidate sail material, aluminized Mylar.

  16. Sea Training at Maritime Academies Oversight. Hearings Before the Ad Hoc Select Subcommittee on Maritime Education and Training of the Committee on Merchant Marine and Fisheries, House of Representatives, Ninety-Sixth Congress, Second Session on Sea Training of United States Merchant Marine Officers and Different Ways of Satisfying This Requirement at the Various Maritime Academies.

    Science.gov (United States)

    Congress of the U.S., Washington, DC. House Committee on Merchant Marine and Fisheries.

    Recorded are minutes of hearings before the House Ad Hoc Select Subcommittee on Maritime Education and Training regarding the sea training of United States Merchant Marine officers. Examined are various approaches to meeting the sea training requirement, especially the options of maritime academy training vessels, sailing on U.S.-flag merchant…

  17. 46 CFR 70.10-1 - Definitions.

    Science.gov (United States)

    2010-10-01

    ..., as required by this subchapter. Point of access means the place on the deck of a vessel where a... a vessel with no mechanical means of propulsion, all propulsive power being provided by sails. Short... between the last port of call in the country in which the voyage begins and the final port of destination...

  18. 33 CFR 117.799 - Long Island, New York Inland Waterway from East Rockaway Inlet to Shinnecock Canal.

    Science.gov (United States)

    2010-07-01

    ... need not be opened for sailing vessels, unless the vessels are under machinery power or under tow, if... bridge, mile 1.1 across Quoque Canal and the Smith Point bridge, mile 6.1 across Narrow Bay shall open on... vessel traffic, provided at least a two-hour advance notice is given by calling the number posted at the...

  19. Differential-drag-based roto-translational control for propellant-less spacecraft

    Science.gov (United States)

    Pastorelli, Mirko; Bevilacqua, Riccardo; Pastorelli, Stefano

    2015-09-01

    This paper proposes a novel technique to perform propellant-free chaser-target spacecraft relative maneuvers while simultaneously stabilizing the chaser's attitude with respect to the local vertical local horizontal coordinate system centered at its body center of mass. The control forces required for relative maneuvers at low Earth orbits can be generated by varying the relative aerodynamic drag via maneuverable sails placed in the back-end of the spacecraft. At the same time, aerodynamic torques resulting from the displacement of the centers of pressure of the sails can stabilize the orientation of the spacecraft. In this work, the target vehicle is assumed to maneuver an identical sail in a cooperative fashion and will be centered and attitude-stabilized in its local vertical local horizontal coordinate system. The proposed approach is based on the idea of virtual thrusters, emulating the sail's center of pressure offset in the controller. Several test cases are presented for various existing spacecraft, demonstrating successful propellant-less roto-translational control of the chaser spacecraft.

  20. The eruption of Vesuvius in AD 79 and the death of Gaius Plinius ...

    African Journals Online (AJOL)

    The effect of the volcanic eruption of Vesuvius in AD 79, which led inter alia to the death of Pliny the Elder, is reviewed. Pliny, the admiral of the Roman imperial fleet, wished as scientist to witness the event from close by and set sail in the direction of Vesuvius, but got trapped in Stabiae, a few kilometers from Pompeii, where ...

  1. Installation Restoration Program. Site Investigation Report for 166th Tactical Airlift Group, Delaware Air National Guard, Greater Wilmington Airport, New Castle, Delaware

    Science.gov (United States)

    1990-05-01

    Polycyclic Aromatic Hydro- carbons" Volumes I-IV; Office of Water Regulations and Standards; WH-553. USEPA, 1988. Superfund Public Health Evaluation Manual ...es EU sailed /V ., j41 Doringdamneter MK. I ~I Weaor 2’ Wonl materil W 40 PC aBwkfMl materiale 54Nw) ZU. DEPTH leg I 4 iiCement grout I - -Flush

  2. 46 CFR 169.107 - Definitions.

    Science.gov (United States)

    2010-10-01

    ... operation and the sea, including seamanship, navigation, oceanography, other nautical and marine sciences...” also includes instruction in mathematics and language arts skills to a sailing school student with a... enclosed equipment constructed so that a stream of water from a hose (not less than 1 inch in diameter...

  3. Dynamic Scheduling for Web Monitoring Crawler

    Science.gov (United States)

    2009-02-27

    pages are related to a specific web page. This project uses classification history of web pages to determine similarity between web pages. That is, web... Badminton , Baseball, Basketball, Boxing, Canoeing, Cycling, Equestrian, Fencing, Gymnastics, Handball, Hocky, Judo, Morden Pentathlon, Rowing, Sailing

  4. Existential well-being : Spirituality or well-being?

    NARCIS (Netherlands)

    Visser, Anja; Garssen, Bert; Vingerhoets, A.J.J.M.

    2017-01-01

    Measures of spirituality often contain the dimension existential well-being (EWB). However, EWB has been found to overlap with emotional and psychological well-being. Using the Spiritual Attitude and Involvement List (SAIL), we have further investigated the overlap between aspects of spirituality

  5. Existential Well-Being Spirituality or Well-Being?

    NARCIS (Netherlands)

    Visser, Anja; Garssen, Bert; Vingerhoets, Ad J. J. M.

    Measures of spirituality often contain the dimension existential well-being (EWB). However, EWB has been found to overlap with emotional and psychological well-being. Using the Spiritual Attitude and Involvement List (SAIL), we have further investigated the overlap between aspects of spirituality

  6. 50 CFR 27.34 - Aircraft.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Aircraft. 27.34 Section 27.34 Wildlife and... WILDLIFE REFUGE SYSTEM PROHIBITED ACTS Disturbing Violations: With Vehicles § 27.34 Aircraft. The unauthorized operation of aircraft, including sail planes, and hang gliders, at altitudes resulting in...

  7. Small-angle neutron scattering study of a dense microemulsion system formed with an ionic liquid.

    Science.gov (United States)

    Kang, T; Qian, S; Smith, G S; Do, C; Heller, W T

    2017-10-11

    Mixtures of water, octane and 1-octanol with 1-tetradecyl-3-methylimidazolium chloride (C14MIM·Cl), often referred to as a surface active ionic liquid (SAIL), form water-in-oil microemulsions that have potential application as extraction media for various metal ions. Here, we present a structural study by small-angle neutron scattering (SANS) of dense microemulsions formed by surfactant-rich mixtures of these four compounds to understand how the SAIL can be used to tune the structures and properties of the microemulsions. The SANS experiments revealed that the microemulsions formed are composed of two phases, a water-in-oil microemulsion and a bicontinuous microemulsion, which becomes the dominant phase at high surfactant concentration. In this concentration regime, the surfactant film becomes more rigid, having a higher bending modulus that results from the parallel stacking of the imidazolium ring of the SAIL. At lower surfactant concentrations, the molecular packing of the SAIL does not change with the water content of the microemulsion. The results presented here correlate well with previously observed changes in the interaction between the IL cation and metal ions (Y. Tong, L. Han and Y. Yang, Ind. Eng. Chem. Res., 2012, 51, 16438-16443), while the capacity of the microemulsion system for water remains high enough for using the system as an extraction medium.

  8. On the Cultural Legacy of the Cold War: Sino-US Educational Exchange (1949-1990)

    Science.gov (United States)

    Gu, Ning

    2006-01-01

    The Cold War affected the Sino-US educational exchange between 1949 and 1990. During those years, preparation for educational exchanges, personal contact and cross-government relations characterized the three periods of the exchanges. However, even though the relationship had developed very fast, it was by no means smooth sailing. These exchanges…

  9. ARN II Program

    Science.gov (United States)

    2004-05-26

    A8 -I .T1111-UY3146 F TcR:, SW32IS2321###IXXX 260900 WODI STREET RECEIVEIG BLDG 3304 SAil DIEGO CA 9213-5-41 UI a C kInmbei .uvey Order S8hnIpmeb...transaction was created. Locator Code VPIS Defense Contract Management District (DCMD), or the Defense Plant Representative Office (DPRO), or Accounting

  10. Modelling of Structural Loads in Drag Augmented Space Debris Removal Concepts

    DEFF Research Database (Denmark)

    Kristensen, Anders Schmidt; Nikolajsen, Jan Ánike; Lauridsen, Peter Riddersholm

    2017-01-01

    A Self-deployable Deorbiting Space Structure (SDSS) is used for drag augmented space debris removal. A highly flexible frame allows for a folding of the structure by bifurcation. This research models the structural loads during the deployment and unfolding of the drag sail in Low Earth Orbit (LEO...

  11. Modelling and Analysis of the Folding Principle used in Selv-Deployable Deorbiting Space Structures

    DEFF Research Database (Denmark)

    Nikolajsen, Jan Ánike; Lauridsen, Peter Riddersholm; Kristensen, Anders Schmidt

    2017-01-01

    An initial prototype of the Self-deployable Deorbiting Space Structure (SDSS) for semi-controlled debris removal was launched in 2014. The SDSS module consists of 3 main systems, i.e. the Drag Sail Unit (DSU), the Release Unit (RU) and the Housing Unit (HU). In the redesign, a storage lid...

  12. Maritime routing and speed optimization with emission control areas

    DEFF Research Database (Denmark)

    Fagerholt, Kjetil; Gausel, Nora T.; Rakke, Jørgen G.

    2015-01-01

    Strict limits on the maximum sulphur content in fuel used by ships have recently been imposed in some Emission Control Areas (ECAs). In order to comply with these regulations many ship operators will switch to more expensive low-sulphur fuel when sailing inside ECAs. Since they are concerned about...

  13. 77 FR 71476 - Requested Administrative Waiver of the Coastwise Trade Laws: Vessel ESCAPADE; Invitation for...

    Science.gov (United States)

    2012-11-30

    ... comments electronically via the Internet at http://www.regulations.gov . All comments will become part of... charters teaching people the fundamentals of cruising under sail. Geographic Region: ``California, Florida... http://www.regulations.gov . Interested parties may comment on the effect this action may have on U.S...

  14. Ancient maritime trade of the eastern Indian littoral

    Digital Repository Service at National Institute of Oceanography (India)

    Tripati, S.

    of the caves, stupas and temples indicate that Buddhist monks, saints, traders and craftsmen used to set sail together. Over a period of time, ancient methods of maritime trade disappeared, and are now only remembered and celebrated as rituals and social events...

  15. Sunken ships and a long-lost port

    Digital Repository Service at National Institute of Oceanography (India)

    Tripati, S.; Sundaresh.; Gaur, A.S.; Vora, K.H.

    Considering that our region’s long seafaring history goes back 2,000 years and more, with a brisk trade being carried on with Arabia, Africa, Rome, West Asia, and later with Portugal, it is safe to assume that hundreds of wooden sailing ships may...

  16. Home | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    2016-12-26

    Dec 26, 2016 ... And what is more, the discovery was made far away from the great centers of scientific research and by using simple equipment aboard a ship sailing in .... from understanding the formation of stars using hyperfine transition of neutral hydrogen, to testing Einstein's theory of general relativity using pulsars, ...

  17. 47 CFR 13.203 - Examination elements.

    Science.gov (United States)

    2010-10-01

    ... Training for Radio Personnel (GMDSS), Annex 3. (7) Element 8: Ship radar techniques. Questions concerning specialized theory and practice applicable to the proper installation, servicing and maintenance of ship radar... procedures and practices that are applicable to ship stations on vessels that sail exclusively in sea area A1...

  18. Inkanyiso full journal 7 Aug 2013.fm

    African Journals Online (AJOL)

    Holardoughyean

    2013-08-07

    Aug 7, 2013 ... the postcolonial continental failure is the erosion of basic African values that have helped to promote stable ..... situation where he is materially more buoyant than the girl, as this would give him more confidence in exercising his authority. The case is ... reason that two captains cannot sail a ship. There is ...

  19. Socio-cultural dynamics and education for development in Zimbabwe

    African Journals Online (AJOL)

    Africa enjoys large numbers of institutions of higher learning and it has seen many women sailing through these institutions. This paper argues that, in spite of the negatives that characterise the educational system in Africa and the marginalisation of most women, there exist avenues that can be exploited to promote and ...

  20. Spelling Correction in User Interfaces.

    Science.gov (United States)

    1982-12-20

    we have concluded that there are considerable benefits and few obstacles to providing a spelling corrector in almost any interactie user interface. Key...the ACAI 23, 12 (December 1980), 676-687. 8. John F. Reiser (ed.). SAIL Manual. Stanford University Computer Science Department, 1976. 9. Warren

  1. The beach-seine fishery off Durban, KwaZulu-Natal

    African Journals Online (AJOL)

    1996-07-23

    Jul 23, 1996 ... reational craft, including ski boats, paddleskis, dive boats and sailing dinghies, also milize this launch site. In recent years, conflict between the seine fishermen and paddleski anglers has escalated, the latter holding the seine fishermen responsi- ble for declining catches, either directly through removal of.

  2. 76 FR 67254 - Requested Administrative Waiver of the Coastwise Trade Laws: Vessel LINDA GRACE; Invitation for...

    Science.gov (United States)

    2011-10-31

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF TRANSPORTATION Maritime Administration Requested Administrative Waiver of the Coastwise Trade Laws: Vessel LINDA GRACE... the vessel LINDA GRACE is: INTENDED COMMERCIAL USE OF VESSEL: ``2 to 8 hour day sails, week-end...

  3. 75 FR 20849 - Notice of Agreements Filed

    Science.gov (United States)

    2010-04-21

    ... Abaco Shipping Company Limited. Filing Parties: Neal M. Mayer, Esq.; Hoppel, Mayer & Coleman; 1050... Latin America Services, LLC.; Dole Ocean Cargo Express; Great White Fleet; King Ocean Services Limited... geographic scope of the Agreement. Agreement No.: 011830-008. Title: Indamex Cross Space Charter, Sailing and...

  4. Longevity Chance

    Directory of Open Access Journals (Sweden)

    Timon Cheng-Yi Liu

    2014-03-01

    Full Text Available Britton Chance pursued his research and sailing until his death at age 97. His 100th anniversary was memorialized in this paper from longevity viewpoint. His lifelong work was very creative. His life was very colorful. His aging was very successful. He has lived a longevity.

  5. In-Space Propulsion Technologies for Robotic Exploration of the Solar System

    Science.gov (United States)

    Johnson, Les; Meyer, Rae Ann; Frame, Kyle

    2006-01-01

    Supporting NASA's Science Mission Directorate, the In-Space Propulsion Technology Program is developing the next generation of space propulsion technologies for robotic, deep-space exploration. Recent technological advancements and demonstrations of key, high-payoff propulsion technologies have been achieved and will be described. Technologies under development and test include aerocapture, solar electric propulsion, solar sail propulsion, and advanced chemical propulsion.

  6. Early adoption of new drug treatments: the role of continuing medical education and physician adaptivity.

    Science.gov (United States)

    Mascarenhas, Desmond; Singh, Baljit K; Singh, Amoolya H; Veer, Sally Vander

    2007-03-01

    The influence of continuing medical education (CME) on the adoption of new treatments is widely regarded as self-evident. Less well understood is how the dynamics of dissemination of new healthcare practices are influenced by the intersection of education with the adaptive characteristics of providers. We developed and validated a 43-item online instrument (eSAIL) for measuring adaptive style and used it to investigate the interplay of physician adaptivity with key components of effective medical education. Satisfactory Cronbach alpha and test-retest reliability coefficients were observed for all primary psychometric scales and a composite adaptivity scale. Discriminant, convergent, and predictive validities of eSAIL scales were consistent across all cohorts. Using an online medical education program for which data on physician behavioral change are available, we show that the rate of adoption of new drugs is driven by both psychological (adaptivity) and environmental (educational) inputs. We show for the first time that topic eminence, length of reinforcement period and physician adaptive score in the eSAIL are each proportional to early-adoption-related behavioral change. Using a simple forced-choice question, a cohort of 208 physicians was segmented into "A" (adaptive) and "C" (conservative) segments based on their eSAIL adaptivity z scores (+0.170 versus -0.234 respectively; P Early adoption of new drug treatments by similarly segmented physician cohorts was driven almost entirely by A-segment physicians, but only when those physicians were additionally exposed to effective medical education.

  7. 77 FR 39395 - Special Local Regulations; Ocean State Tall Ships Festival 2012, Narragansett Bay, RI

    Science.gov (United States)

    2012-07-03

    ... effect for only a portion of one day centered on the Parade of Sail, and most vessel traffic can pass... INFORMATION CONTACT. Small businesses may send comments on the actions of Federal employees who enforce, or... on actions by employees of the Coast Guard, call 1-888-REG-FAIR (1-888-734-3247). The Coast Guard...

  8. The Effects of Target Location Uncertainty in Game Theoretic Solutions to Optimal Trajectory Formulations

    Science.gov (United States)

    2005-06-01

    recoverable or expendable and can be piloted remotely or �y autonomously, meaning without any human aid. Robotic weapons and cruise missiles are even considered...stress. -Identify color of unfurled sails on sailboats (20 to 30 feet in length). -Distinguish between military and civilian helicopters paint schemes

  9. Manning orientated design in The Netherlands

    NARCIS (Netherlands)

    Post, W.M.

    2011-01-01

    All navies, when taking initiative to build a new platform, have difficulties with determining in an early phase the number of people that are needed to sail the planned ship. How do you approach this problem? How can you reduce the complexity of it? How do you reach a cost-effective solution? How

  10. Functional Job Analysis of Marine Personnel Employed on Offshore Supply Vessels,

    Science.gov (United States)

    1982-01-01

    evaluating the significance of operational hazards and identifying critical tasks. Data ws reviewed for the fiscal years 1976 - 1979 and is presented in Tble...internal combustion engines, electric wiring sys- tems, nursing, farm management, ship sailing, or machining. * Apply principles to solve practica

  11. Examining Risk-Taking Behavior and Sensation Seeking Requirement in Extreme Athletes

    Science.gov (United States)

    Agilonu, Ali; Bastug, Gulsum; Mutlu, Tonguc Osman; Pala, Adem

    2017-01-01

    Extreme sports are sport branches which include actions, adventures, risks and difficulties more rather than other sports. Special materials are used in sport branches such as surfing, kite surfing, sailing, snowboarding, paragliding, diving, mountaineering, motor sports and adrenaline release is more rather than in other sport branches. On the…

  12. From El Wak to Sidi Rezegh: The Union Defence Force's First ...

    African Journals Online (AJOL)

    While Hitler's armies conquered. Western Europe the Springboks prepared to go North and in spite of trepidations about the might of Mussolini's East African Empire the First South African Infantry Division set sail for East Africa in mid-July 1940. In five short months, Mussolini's East African Empire had been torn to shreds.

  13. banks

    Directory of Open Access Journals (Sweden)

    Elena Grigoryeva

    2017-01-01

    The thaw period was a kind of bank from which our country set sail towards unexplored horizons. The series on the Moscow Palace of Young Pioneers is continued by the article by Felix Novikov (144-151, who writes about the history of the design of this wonderful building, today’s monument of architecture of Soviet modernism.

  14. High-speed Impact Modelling and Testing of Dyneema Composite

    NARCIS (Netherlands)

    Heru Utomo, B.D.

    2011-01-01

    Dyneema (Ultra High Molecular Weight Polyethylene – UHMW PE) is a high performance material that is used in many applications. These applications vary from leisure articles such as sails and kite wires to surgical wires and personal protection products. The reason that Dyneema outperforms many other

  15. Prototype Development and Dynamic Characterization of Deployable CubeSat Booms

    Science.gov (United States)

    2010-03-01

    ideas of navigating the cosmos via sails captivating the imaginations of such luminaries as Galileo Galilei and Johannes Kepler. As Kepler once stated...Gossamer Spacecraft: Why Aren’t There More (Yet)? 50th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference. Palm Springs, CA

  16. Social and spatial foraging patterns of the jackass penguin ...

    African Journals Online (AJOL)

    The inshore distribution and foraging behaviour of jackass penguins Spheniscus demersus were studied between December 1982 and August 1983 in waters close to breeding islands in Saldanha Bay, South Africa. The use of a sail-boat permitted close observation of foraging penguins with minimal apparent disturbance.

  17. Naval War College Review. Volume 66, Number 3, Summer 2013

    Science.gov (United States)

    2013-01-01

    hip . in an important sense, this is the basic motivation underlying America’s unrelenting efforts in recent years to stir up trouble and discontent...gave them knowledge of the course and composition of every Axis convoy to Africa before it sailed. ULTRA contributed to the defeat of the Axis thrust

  18. Competitive Liner Shipping Network Design

    DEFF Research Database (Denmark)

    Karsten, Christian Vad; Brouer, Berit Dangaard; Pisinger, David

    2017-01-01

    leg are used to balance sailing speed against operational costs, hence ensuring that the found network is competitive on both transit time and cost. We present a matheuristic for the problem where a MIP is used to select which ports should be inserted or removed on a route. Computational results...... on fluctuations in bunker price which confirms the applicability of the algorithm....

  19. Fulltext PDF

    Indian Academy of Sciences (India)

    skills of the navigator and the artisan. Huge profits were waiting to be made if ships could sail to distant lands ... Europeans took great interest in the skills and knowledge of the natives in India and the East in general for the sake of ..... taking the help of local leaders. Inoculations were to be conducted 'at first according to the ...

  20. JPRS Report, China.

    Science.gov (United States)

    1990-05-14

    attending. As a result, since last year, Taiwan has sent gymnasts , table tennis players, athletes in judo, handball, basketball, sailing, archery...organizations also often visit foreign countries. The Shenyang and Dalian acrobatic troupes, the Haicheng Stilts and Yangko troupe, and the peasant brass

  1. Ship-Iceberg Discrimination in Sentinel-2 Multispectral Imagery by Supervised Classification

    DEFF Research Database (Denmark)

    Heiselberg, Peder; Heiselberg, Henning

    2017-01-01

    The European Space Agency Sentinel-2 satellites provide multispectral images with pixel sizes down to 10 m. This high resolution allows for fast and frequent detection, classification and discrimination of various objects in the sea, which is relevant in general and specifically for the vast Arct......, the false alarm rate dominates for small non-sailing boats....

  2. 46 CFR 169.323 - Furniture and furnishings.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Furniture and furnishings. 169.323 Section 169.323... Construction and Arrangement Living Spaces § 169.323 Furniture and furnishings. Each sailing school vessel... furniture must be constructed of noncombustible material. Upholstery and padding used in furniture must be...

  3. From Cold War to Arctic Battle?

    DEFF Research Database (Denmark)

    Jensen, Boris Brorman

    2012-01-01

    Greenland and the whole Arctic region is becoming a geopolitical hot spot. The opening of new potential sail routes to Asia and the possible exploitation of oil, gas and other natural resources like rare earth minerals are creating a window of opportunity for Greenland. What are the risks and who...

  4. Identification of virulence factors and type III effectors of Phylotype I ...

    Indian Academy of Sciences (India)

    HP2000

    Remigi P., Anisimova M., Guidot A., Genin S. and Peeter N. 2011 Functional diversification of the GALA type III effector family contributes to Ralstonia solanacearum adaptation on different plant hosts. New Phytol. 192, 976-987. Saile,E., McGarvey, J., Schell, M. and Denny, T. 1997 Role of Extracellular Polysaccharide and.

  5. Detachment 101 in the CBI: An Unconventional Warfare Paradigm for Contemporary Special Operations

    Science.gov (United States)

    2010-05-13

    uncovered the Japanese plans to sail to Lae , New Guinea. The second event facilitated the destruction of Japanese air power over New Guinea. The third...incompatible. The methods used in Afghanistan include placing large bits of data on ‘thumb drives’ and walking a ‘ soft copy’ over to our coalition partners

  6. From Napoleon To Netanyahu: Blockading Through Two Centuries

    Science.gov (United States)

    2016-04-01

    accompanied this technological revolution . The Declaration of Paris (1856), abolished privateering, protected enemy goods sailing under neutral...Cruz during the Mexican War proved difficult with the nearest coaling station 900 miles away in Pensacola, Florida. The United States possessed only

  7. 46 CFR 169.825 - Wearing of safety belts.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Wearing of safety belts. 169.825 Section 169.825 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Operations § 169.825 Wearing of safety belts. The master of each vessel shall ensure that each person wears...

  8. Understanding Global / Local Cultural Leadership : Issues and Methods

    NARCIS (Netherlands)

    Kolsteeg, Johan

    2017-01-01

    Cultural leaders sail between the Scylla and Charibdis of aggregated trans- and supranational cultural-political discourses and the cultural needs of local communities. How do these dynamics influence the work of cultural leaders? How can we understand the work of cultural leaders to connect

  9. Quetzalcoatl and the Golden Age of Mesoamerica.

    Science.gov (United States)

    Ramirez-Heil, Celia

    1978-01-01

    Quetzalcoatl was both man and god, myth and true history, and was worshipped through centuries in temples in the great sacred cities of Teotihuacan, Tollan, and Chichen Itza. The White god, ruler of the Toltec golden age, who sailed toward the east promising to return, remains a mystery. (Author/NQ)

  10. Dynamic Modeling and Simulation of Marine Satellite Tracking Antenna Using Lagrange Method

    DEFF Research Database (Denmark)

    Wang, Yunlong; Soltani, Mohsen; Hussain, Dil muhammed Akbar

    2016-01-01

    Marine Satellite Tracking Antenna (MSTA) is a necessary device in ships for receiving satellite signals when they are sailing on the sea. This paper presents a simple methodology to obtain the dynamic equations of MSTA through Lagrange method, which is fundamental in design of modelbased...

  11. 46 CFR 169.805 - Exhibition of merchant mariner credentials.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Exhibition of merchant mariner credentials. 169.805 Section 169.805 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Operations § 169.805 Exhibition of merchant mariner credentials. Officers on any vessel...

  12. Climate windows for Polynesian voyaging to New Zealand and Easter Island.

    Science.gov (United States)

    Goodwin, Ian D; Browning, Stuart A; Anderson, Atholl J

    2014-10-14

    Debate about initial human migration across the immense area of East Polynesia has focused upon seafaring technology, both of navigation and canoe capabilities, while temporal variation in sailing conditions, notably through climate change, has received less attention. One model of Polynesian voyaging observes that as tradewind easterlies are currently dominant in the central Pacific, prehistoric colonization canoes voyaging eastward to and through central East Polynesia (CEP: Society, Tuamotu, Marquesas, Gambier, Southern Cook, and Austral Islands) and to Easter Island probably had a windward capacity. Similar arguments have been applied to voyaging from CEP to New Zealand against prevailing westerlies. An alternative view is that migration required reliable off-wind sailing routes. We investigate the marine climate and potential voyaging routes during the Medieval Climate Anomaly (MCA), A.D. 800-1300, when the initial colonization of CEP and New Zealand occurred. Paleoclimate data assimilation is used to reconstruct Pacific sea level pressure and wind field patterns at bidecadal resolution during the MCA. We argue here that changing wind field patterns associated with the MCA provided conditions in which voyaging to and from the most isolated East Polynesian islands, New Zealand, and Easter Island was readily possible by off-wind sailing. The intensification and poleward expansion of the Pacific subtropical anticyclone culminating in A.D. 1140-1260 opened an anomalous climate window for off-wind sailing routes to New Zealand from the Southern Austral Islands, the Southern Cook Islands, and Tonga/Fiji Islands.

  13. 78 FR 40396 - Safety Zone; America's Cup Safety Zone and No Loitering Area, San Francisco, CA

    Science.gov (United States)

    2013-07-05

    ... have questions on this rule, call or email Lieutenant Junior Grade William Hawn, U.S. Coast Guard... America's Cup sailing regattas and discuss measures for prevention and response. During this exercise... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; America's Cup Safety Zone and No Loitering...

  14. 76 FR 12219 - Information Collection Available for Public Comments and Recommendations

    Science.gov (United States)

    2011-03-04

    ... time of their enrollment in a Federal maritime training program. It also permits the Maritime..., they are required first to sail on their professional merchant marine licenses or work in the maritime industry ashore. This dual role makes the graduates especially valuable because national defense planning...

  15. 46 CFR 116.438 - Stairtowers, stairways, ladders, and elevators.

    Science.gov (United States)

    2010-10-01

    ... equal to the square of the tread width must be provided at the top and bottom of each stairway; and (2... leading to a stairtower enclosure that includes self closing fire doors at both the top and bottom; or... handling lifesaving equipment, anchor handling equipment, or line handling gear, or in way of sail booms or...

  16. 78 FR 30302 - Notice of Agreements Filed

    Science.gov (United States)

    2013-05-22

    ... 10024. Synopsis: The amendment deletes Peru from the geographic scope of the agreement. Agreement No.: 011885-003. Title: CMA CGM/MSC Reciprocal Space Charter, Sailing and Cooperative Working Agreement... Indonesia from the geographic scope of the agreement. By Order of the Federal Maritime Commission. Dated...

  17. 77 FR 28880 - Notice of Agreements Filed

    Science.gov (United States)

    2012-05-16

    ... geographic scope of the agreement. Agreement No.: 012170. Title: Crowley/SC Line Space Charter and Sailing... . Agreement No.: 012028-001. Title: WWL/Hoegh Middle East Space Charter Agreement. Parties: Hoegh Autoliners... authorizes SC Line to charter space to Crowley in the trade between the U.S. Atlantic Coast and ports in...

  18. Applications of Superconductivity to Avionics: Proceedings of a Conference Held in Bath, England on May 7-8, 1990 (Les Applications de la Supraconductivite dans le Domains de l’Avionique)

    Science.gov (United States)

    1990-10-01

    National a -’vs c Laboratory, 7-9 N-. 1989. 191 Jordan P.C. "Electromagnetic waves and radial ing sstems", Pr et ice Sail, New Jerney, 1968. 10) Walker...1989, A Publication of TMS, pp. 463-470. 14. Hojaji, H.; Micheal , K. A.; Barkatt, A.; Thorpe, A. N.; Ware, M. F.; Talmy, I.; Haught, 0. A.; Alterescu

  19. Determination of cmc of imidazolium based surface active ionic liquids through probe-less UV-vis spectrophotometry.

    Science.gov (United States)

    Rather, Mudasir Ahmad; Rather, Ghulam Mohammad; Pandit, Sarwar Ahmad; Bhat, Sajad Ahmad; Bhat, Mohsin Ahmad

    2015-01-01

    In the first of its kind we herein report the results of our studies undertaken on the micellization behaviour of imidazolium based surface active ionic liquids (SAILs) to prove that their critical micelle concentration (cmc) can be estimated through ultraviolet-visible (UV-vis) spectroscopy without using any external probe. Tensiometric and spectrophotometric investigations of a series of freshly prepared SAILs viz. 1-octyl-3-methylimidazolium chloride ([OMIM][Cl]), 1-octyl-3-methylimidazolium dodecylsulphate ([OMIM][DS]), 1-octyl-3-methylimidazolium benzoate ([OMIM][Bz]), 1-octyl-3-methylimidazolium salicylate ([OMIM][Sc]), 1-octyl-3-methylimidazolium acetate ([OMIM][Ac]) are presented as a case study in support of the said claim. The cmcs estimated through spectrophotometric method were found to be close to the values estimated through tensiometry for the said SAILs. The cmcs for the investigated SAILS were found to vary in order of [OMIM][Cl]>[OMIM][Ac]>[OMIM][Bz]>[OMIM][Sc]>[OMIM][DS]. To the best of our knowledge the present communication will be the first report about the synthesis, characterization and micellization behaviour of [OMIM][Bz] and [OMIM][Sc]. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Naval War College Review. Volume 66, Number 2, Spring 2013

    Science.gov (United States)

    2013-01-01

    Professor luke holds a merchant mariner’s license in the grade of Unlimited ocean Master, Steam, Motor, or Sail.) Much of his service was in the law...way of contrast, neglected their navies prior to the outbreak of war, and only strenuous efforts after its onset, aid- ed by french timidity , staved

  1. Reviewing and Viewing.

    Science.gov (United States)

    Allinger, Glenn D., Ed.; And Others

    1988-01-01

    Reviews following computer materials: Coordinate Math; How the West Was One + Three x Four; Math Facts Lottery, Basic Skills Game; Math Tutor, Division; Now You See It, Now You Don't; Pinball Math, Basic Skills Game; Place Value-Add/Subtract; Quarter Mile; Regrouping; Sailing through Story Problems; Scope Math, Computer Mathematics Course for…

  2. The more involved in lead-zinc mining risk the less frightened : A psychological typhoon eye perspective

    NARCIS (Netherlands)

    Zheng, Rui; Rao, Li Lin; Zheng, Xiao-Lu; Cai, Chao; Wei, Zi Han; Xuan, Yan Hua; Li, Shu

    2015-01-01

    In China, the current situation is that people under indirect threat from unprotected lead-zinc mining tends to oppose it, whereas people under direct threat are likely to 'sail close to the wind'. To understand this puzzle-like phenomenon, we surveyed 220 residents in a lead-zinc mining area

  3. Nonlinear State and Parameter Estimation for Hopper Dredgers

    NARCIS (Netherlands)

    Stano, P.M.

    2013-01-01

    A Trailing Suction Hopper Dredger (TSHD) is a ship that excavates sediments from the sea bottom while sailing. In situ material is excavated with a special tool called the Drag-Head, then it is hydraulically transported through a pipe to the hopper where it is temporarily stored. After the dredging

  4. Encountered Wave Height Distributions for Ships in the North Atlantic

    DEFF Research Database (Denmark)

    Olsen, Anders Smærup; Schrøter, C.; Jensen, Jørgen Juncher

    2004-01-01

    About 20 000 observations of wave heights taken on board vessels sailing in the North Atlantic are presented. The data covers year 2002 and 2003 and stem from a variety of ship types. From the preliminary analysis of the data some conclusions are reached about the effect of weather routing whether...

  5. Muusika / Mart Juur

    Index Scriptorium Estoniae

    Juur, Mart, 1964-

    2005-01-01

    Uutest heliplaatidest Pia Fraus "Sailing On A Grapefruit Lake", Six Organs Of Admittance "School Of The Flower", Jaga Jazzist "What We Must", Oasis "Don't Belive The Truth", Limp Bizkit "The Unquestionable Truth", "Do Me Bad Things", Saari, Jarmo "Solu", Cave, Nick & The Bad Seeds "B-Sides & Rarities", "Stars Wars", Weezer "Make Believe"

  6. SunJammer Technology Demonstration

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Sunjammer Project is a NASA funded contract to L?Garde Inc. to fly a solar sail demonstration for a period of approximately one year. L?Garde is also partnered...

  7. Manpower Procurement Policies, Ground Force Structures, and Registration Systems: Denmark, the Federal Republic of Germany, Norway, and the United Kingdom.

    Science.gov (United States)

    1981-02-01

    planning to trdvel abroad, emmigrate or take a job on a merchant ship sailing only on foreign ports, they must apply to their units for permission. 1 In...to introduce conscription possibly by 1982 (the earlier decision to introduce conscription in 1979 was delayed). Malaysia and the Republic of South

  8. Manning Centered Design in The Netherlands

    NARCIS (Netherlands)

    Post, W.M.

    2010-01-01

    All navies, when taking initiative to build a new platform, have difficulties with determining in an early phase the number of people that are needed to sail the planned ship. How do you approach this problem? Where do you start? How can you reduce the complexity of it? Later on, at planning a

  9. A Solar Sailcraft Simulation Application

    Science.gov (United States)

    Celeda, Tomáš

    2013-01-01

    An application was created to encourage students' practical knowledge of gravitational fields, the law of conservation of energy and other phenomena, such as gravitational slingshots. The educational software simulates the flight of a solar sail spacecraft between two planets of the Solar System using the laws of gravity and radiation…

  10. Positive allometry and the prehistory of sexual selection.

    Science.gov (United States)

    Tomkins, Joseph L; LeBas, Natasha R; Witton, Mark P; Martill, David M; Humphries, Stuart

    2010-08-01

    The function of the exaggerated structures that adorn many fossil vertebrates remains largely unresolved. One recurrent hypothesis is that these elaborated traits had a role in thermoregulation. This orthodoxy persists despite the observation that traits exaggerated to the point of impracticality in extant organisms are almost invariably sexually selected. We use allometric scaling to investigate the role of sexual selection and thermoregulation in the evolution of exaggerated traits of the crested pterosaur Pteranodon longiceps and the sail-backed eupelycosaurs Dimetrodon and Edaphosaurus. The extraordinarily steep positive allometry of the head crest of Pteranodon rules out all of the current hypotheses for this trait's main function other than sexual signaling. We also find interspecific patterns of allometry and sexual dimorphism in the sails of Dimetrodon and patterns of elaboration in Edaphosaurus consistent with a sexually selected function. Furthermore, small ancestral, sail-backed pelycosaurs would have been too small to need adaptations to thermoregulation. Our results question the popular view that the elaborated structures of these fossil species evolved as thermoregulatory organs and provide evidence in support of the hypothesis that Pteranodon crests and eupelycosaur sails are among the earliest and most extreme examples of elaborate sexual signals in the evolution of terrestrial vertebrates.

  11. 46 CFR 173.061 - Watertight integrity above the margin line.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Watertight integrity above the margin line. 173.061 Section 173.061 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SUBDIVISION AND... margin line. The watertight integrity of each sailing school vessel above the margin line must comply...

  12. Acetylcholinesterase activity in marine gastropods as biomarker of neurotoxic contaminants

    Digital Repository Service at National Institute of Oceanography (India)

    Sarkar, A.; Gaitonde, D.C.S.; Vashistha, D.

    the same trend of low AChE activities. The sources of contamination at the sampling sites at Dona Paula are very much similar to those at Vasco sites because of the extensive maritime activities such as sailing of oil tanker, cargo ships and barges carrying...

  13. Ancient technology of jetties and anchorage system along the Saurastra coast, India

    Digital Repository Service at National Institute of Oceanography (India)

    Gaur, A.S.; Sundaresh

    , at places where there are no jetties, even very large sailing ships were run aground at high tide. As the tide receded leaving bare sand beneath the ship, passengers and cargo were moved to and fro, with the help of large carts drawn by bullocks (Mc...

  14. The Coast Artillery Journal. Volume 73, Number 1, July 1930

    Science.gov (United States)

    1930-07-01

    clockwork . There were no delays or mishaps. ~While the plancs were up, two or three, including one from the Lexington, made forced landings, This simply...instructor, Coast Artillery School, to Philippines, sailing New York, August 20. Maj. Charles J. Schaefer, Jr., CA-Res., from East Orange , N. J., to

  15. High Incidence of Cyanobacterial Blooms along the Coast of the ...

    African Journals Online (AJOL)

    The coast of the Cameroon Gulf of Guinea (GoG) comprises areas like the, Idenau beach, Mudeka/Tiko creeks, Limbe estuary and Douala Lagoon most of which are in the immediate vicinity of industrial zones, logging stations and an oil refinery. They serve as centres for recreational sailing, fin and shellfish fisheries and ...

  16. Parent and Athlete Perceptions of Special Olympics Participation: Utility and Danger of Proxy Responding

    Science.gov (United States)

    Glidden, Laraine Masters; Bamberger, Katharine T.; Draheim, Angela R.; Kersh, Joanne

    2011-01-01

    Participation in athletics has benefits for persons with intellectual disabilities and their parents. Our purposes here were to confirm these benefits and to determine whether reports from athletes and parents were comparable (i.e., to test the validity of proxy responding). We conducted interviews with 34 Special Olympics sailing/kayaking…

  17. 46 CFR 350.4 - Eligibility for awards.

    Science.gov (United States)

    2010-10-01

    ... War II sailing history to include—theater(s) of operation and ports of discharge; and (3) Book number or United States Maritime Service (USMS) number and World War II home address. (b) Korean and Vietnam Awards. Applicants for the Korean Service bar and medal, Vietnam Service bar and medal and the Merchant...

  18. Effect of ship motion on spinal loading during manual lifting

    NARCIS (Netherlands)

    Faber, G.S.; Kingma, I.; Delleman, N.; Dieën, J. van

    2008-01-01

    This study investigated the effects of ship motion on peak spinal loading during lifting. All measurements were done on a ship at sea. In 1-min trials, which were repeated over a wide range of sailing conditions, subjects lifted an 18 kg box five times. Ship motion, whole body kinematics, ground

  19. 46 CFR 169.669 - Radiotelephone equipment.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Radiotelephone equipment. 169.669 Section 169.669 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS... of Less Than 100 Gross Tons § 169.669 Radiotelephone equipment. A separate circuit from the...

  20. 46 CFR 169.705 - Mooring equipment.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Mooring equipment. 169.705 Section 169.705 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Vessel Control, Miscellaneous Systems, and Equipment § 169.705 Mooring equipment. Each vessel must be fitted with...