WorldWideScience

Sample records for sailing ships

  1. 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...

  2. 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?

  3. 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.

  4. 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.

  5. 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...... fuel oil (HFO) outside the ECA and switch to low-sulfur fuel such as marine gas oil (MGO) inside the ECA. As the prices of these two fuels are generally very different, so may be the speeds that the ship will sail at outside and inside the ECA. The first optimization problem examined by the paper...

  6. 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...

  7. 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...

  8. Laddermill-sailing. Ship propulsion by wind energy independent from the wind direction

    Energy Technology Data Exchange (ETDEWEB)

    Ockels, W. J.

    2007-12-15

    The use of large kites in ship propulsion has been getting a growing attention because of the urgent need to reduce the CO2 production and thus stop the use of fossil fuels. A novel application of ship propulsion by kites is proposed based on a Laddermill apparatus mounted on a ship. Such an apparatus consist of a winch, an electric motor/generator, a kite system (including launch and retrieval) and controlling electronics. Rather than the traditional sailing by wind force the Laddermill propulsion is achieved by a combination of the production and use of electrical power and the direct pulling force from the kite system. The feasibility of this application is investigated. It is shown that when the overall Laddermill to ship thrust efficiency can be made around 50% the resulting speed of the ship becomes practically independent from the wind direction. Such a capability could thus well change the world's seafaring.

  9. Wave Loads on Ships Sailing in Restricted Water Depth

    DEFF Research Database (Denmark)

    Vidic-Perunovic, Jelena; Jensen, Jørgen Juncher

    2003-01-01

    depth for a container vessel. The results show that if the water depth is less than two times the draft of the vessel, the wave-induced bending moment becomes significant larger than in deep water with the same sea state description. The peak in the frequency response function for the wave bending......The wave-induced bending moment in ships is the most important sea load parameter for ships larger than 100m in length. Hence, any rational ship design procedure must include a reasonable accurate determination of this load and a large amount of various hydrodynamic formulations have been published......, ranging from semi-empirical formulas to three-dimensional non-linear procedures. A review of the state-of-the art can be found in ISSC.VI.1 (2000). These procedures must be combined with operational and sea state information to predict the probability distribution of the maximum wave-induced bending...

  10. 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.

  11. WORLD TRAINING SAILING BOATS

    Directory of Open Access Journals (Sweden)

    Svitlana Yeroshkina

    2016-06-01

    Full Text Available In scientific article is researched tendencies, which took place in historical process of the world segmentation of sailing tall ships and their influence on modern composition on whole word’s training sailing boats. By variety parameters modern composition of ships was done the estimation of most biggest tall sailing ships. Complete technical description of the powerful sailing tall ships was done on the present day. Identified and given the technical possibilities for further exploitation of  Ukrainian training sailing boats. Assesses the current state of the sailing fleet in terms of economic costs and expenses of Crimea’s occupation and continuous war on eastern region of Ukraine.Key words: training sailing boats, world segment of sailing boats, sailing boats. JEL: L 92

  12. Effects of a Tall Ship Sail Training Experience on Adolescents' Self-Concept

    Science.gov (United States)

    Capurso, Michele; Borsci, Simone

    2013-01-01

    This study investigates the impact of a sail training education programme on the self-concept of a group of 147 adolescents. The Competence and Social domains of Bracken's self-concept scale were assessed by a quasi-experimental design in three phases: before commencement of the activities, on the last day of the voyage, and three months after…

  13. 46 CFR 15.725 - Sailing short.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Sailing short. 15.725 Section 15.725 Shipping COAST... Limitations and Qualifying Factors § 15.725 Sailing short. Whenever a vessel is deprived of the service of a... vessel is sufficiently manned for the voyage. A report of sailing short must be filed in writing with the...

  14. 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

  15. Sail '76

    Science.gov (United States)

    Vandewalle, Raymond

    1976-01-01

    A new nationwide program called Sail '76 has been launched to give more people the opportunity to try the sport of sailing and to teach people the proper sailing techniques before they invest in a sailboat. (SK)

  16. Experimental and Numerical Analysis of Hull Girder Vibrations and Bow Impact of a Large Ship Sailing in Waves

    Directory of Open Access Journals (Sweden)

    Jialong Jiao

    2015-01-01

    Full Text Available It is of great importance to evaluate the hull structural vibrations response of large ships in extreme seas. Studies of hydroelastic response of an ultra large ship have been conducted with comparative verification between experimental and numerical methods in order to estimate the wave loads response considering hull vibration and water impact. A segmented self-propelling model with steel backbone system was elaborately designed and the experiments were performed in a tank. Time domain numerical simulations of the ship were carried out by using three-dimensional nonlinear hydroelasticity theory. The results from the computational analyses have been correlated with those from model tests.

  17. Optimization of the Costs and the Safety of Maritime Transport by Routing: The use of Currents Forecast in the Routing of Racing Sail Boats as a Prototype of Rout Optimization for Trading Ships

    Science.gov (United States)

    Theunynck, Denis; Peze, Thierry; Toumazou, Vincent; Zunquin, Gauthier; Cohen, Olivier; Monges, Arnaud

    2005-03-01

    It is interesting to see whether the model of routing designed for races and great Navy operations could be transferred to commercial navigation and if so, within which framework.Sail boat routing conquered its letters of nobility during great races like the « Route du Rhum » or the transatlantic race « Jacques Vabre ». It is the ultimate stage of the step begun by the Navy at the time of great operations, like D-day (Overlord )June 6, 1944, in Normandy1.Routing is, from the beginning, mainly based on statistical knowledge and weather forecast, but with the recent availability of reliable currents forecast, sail boats routers and/or skippers now have to learn how to use both winds and currents to obtain the best performance, that is to travel between two points in the shortest time possible in acceptable security conditions.Are the currents forecast only useful to racing sail boat ? Of course not, they are a great help to fisherman for whom the knowledge of currents is also the knowledge of sea temperature who indicates the probability of fish presence. They are also used in offshore work to predict the hardness of the sea during operation.A less developed field of application is the route optimization of trading ships. The idea is to optimize the use of currents to increase the relative speed of ships with no augmentation of fuel expense. This new field will require that currents forecasters learn about the specific needs of another type of clients. There is also a need of teaching because the future customers will have to learn how to use the information they will get.At this point, the introduction of the use of currents forecast in racing sail boats routing is only the first step. It is of great interest because it can rely on a high knowledge in routing.The main difference is of course that the wind direction and its force are of greater importance to a sail boat that they are for a trading ship for whom the point of interest will be the fuel consumption

  18. 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.

  19. 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

  20. Shipping

    NARCIS (Netherlands)

    Wijnolst, N.; Wergeland, T.

    1996-01-01

    Shipping is a multi-faceted industry which is rather complex to define from an academic point of view. This book attempts to grasp these complexities and provide the reader with an overview of the main topics and terminology in shipping. The book is based on material from our courses in shipping at

  1. FASt - An autonomous sailing platform for oceanographic missions

    OpenAIRE

    Jose C Alves; Nuno A Cruz

    2008-01-01

    Sailing has been for long times the only means of ship propulsion at sea. Although the performance of a sailing vessel is well below the present power driven ships, either in terms of navigation speed and predictability, wind energy is absolutely renewable, clean and free. Unmanned autonomous sailing boats may exhibit a virtually unlimited autonomy and be able to perform unassisted missions at sea for long periods of time. Promising applications include oceanographic and weather data collecti...

  2. 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.

  3. Shipping

    OpenAIRE

    Wijnolst, N.; Wergeland, T.

    1996-01-01

    Shipping is a multi-faceted industry which is rather complex to define from an academic point of view. This book attempts to grasp these complexities and provide the reader with an overview of the main topics and terminology in shipping. The book is based on material from our courses in shipping at the universities in Delft and Bergen. As with our lectures, we draw upon quite a va ried material, from research studies at a high academic level to lower level student work and purely descriptive ...

  4. 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.

  5. Ship

    OpenAIRE

    Keuning, J.A.

    2008-01-01

    The invention concerns a ship designed for use at high speed and heavy seas having a single long and slender hull with a narrow beam and a more or less vertical bow, whereby the front half of the hull has more or less vertical sides, minimal flare in the bow sections and towards the bow an increase in draught at its center line combined with a more or less similar increase of freeboard and whereby the aft end of the hull has a flat or slightly V-shaped bottom with one or more propellers and/o...

  6. 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.

  7. Lightweight Light Sail Propulsion

    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...

  8. Liner Shipping Fleet Repositioning

    DEFF Research Database (Denmark)

    Tierney, Kevin; Jensen, Rune Møller

    2011-01-01

    Liner shipping fleet repositioning consists of moving vessels between services in a liner ship- ping network in order to better orient the overall network to the world economy, and to ensure the proper maintenance of vessels. Thus, fleet repositioning involves sailing and loading activities subject...

  9. 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

    As Arctic sea ice coverage declines it is expected that marine traffic could increase in this northern region due to shorter routes. Navigating in the Arctic offers opportunities and challenges for waste heat recovery systems (WHRS). Lower temperatures require larger heating power on board, hence...... 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...

  10. 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.

  11. 46 CFR 169.721 - Storm sails and halyards (exposed and partially protected waters only).

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Storm sails and halyards (exposed and partially... § 169.721 Storm sails and halyards (exposed and partially protected waters only). (a) Unless clearly unsuitable, each vessel must have one storm trysail of appropriate size. It must be sheeted independently of...

  12. Luffing of planar sails

    International Nuclear Information System (INIS)

    Newman, B.G.

    1985-01-01

    In this paper the luffing of an unstiffened, two-dimensional impervious membrane is examined. When a sail boat is close-hauled the sails are required to generate high 'lift' with minimum drag. They therefore operate, as do those on hang-wing gliders, at incidences below the stall. However, unlike solid wings they must also avoid negative incidences for then a sail begins to lose its concave shape, to become S shaped and finally, as the incidence is further reduced, to oscillate, a behaviour known as luffing

  13. Speed Optimization in Liner Shipping Network Design

    DEFF Research Database (Denmark)

    Brouer, Berit Dangaard; Karsten, Christian Vad; Pisinger, David

    In the Liner Shipping Network Design Problem (LSNDP) services sail at a given speed throughout a round trip. In reality most services operate with a speed differentiated head- and back-haul, or even individual speeds on every sailing between two ports. The speed of a service is decisive...

  14. The Physics and Technology of Solar Sail Spacecraft.

    Science.gov (United States)

    Dwivedi, B. N.; McInnes, C. R.

    1991-01-01

    Various aspects of the solar sail spacecraft such as solar sailing, solar sail design, navigation with solar sails, solar sail mission applications and future prospects for solar sailing are described. Several possible student projects are suggested. (KR)

  15. 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

  16. 46 CFR 169.817 - Master to instruct ship's company.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Master to instruct ship's company. 169.817 Section 169.817 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Operations § 169.817 Master to instruct ship's company. The master shall conduct drills and give instructions as necessary to insure that al...

  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. Experiments on sail aerodynamics

    International Nuclear Information System (INIS)

    Greenhalgh, S.; Curtiss, H.C.

    1985-01-01

    This paper will present the results of experimental and analytical studies of membrane lifting surfaces that serve as a starting point for a more systematic study of sails. The work is an extension of earlier studies conducted on two-dimensional membrane lifting surfaces. (author)

  19. SAIL: automating interlibrary loan.

    Science.gov (United States)

    Lacroix, E M

    1994-01-01

    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. PMID:8004020

  20. 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

  1. Navy Ship Propulsion Technologies: Options for Reducing Oil Use - Background for Congress

    National Research Council Canada - National Science Library

    O'Rourke, Ronald

    2006-01-01

    ...; and using sail and solar power. Reducing energy use on Navy ships. A 2001 study concluded that fitting a Navy cruiser with more energy-efficient electrical equipment could reduce the ship's fuel use by 10% to 25...

  2. Design of Sail-Assisted Unmanned Surface Vehicle Intelligent Control System

    Directory of Open Access Journals (Sweden)

    Yong Ma

    2016-01-01

    Full Text Available To achieve the wind sail-assisted function of the unmanned surface vehicle (USV, this work focuses on the design problems of the sail-assisted USV intelligent control systems (SUICS and illustrates the implementation process of the SUICS. The SUICS consists of the communication system, the sensor system, the PC platform, and the lower machine platform. To make full use of the wind energy, in the SUICS, we propose the sail angle of attack automatic adjustment (Sail_4A algorithm and present the realization flow for each subsystem of the SUICS. By using the test boat, the design and implementation of the SUICS are fulfilled systematically. Experiments verify the performance and effectiveness of our SUICS. The SUICS enhances the intelligent utility of sustainable wind energy for the sail-assisted USV significantly and plays a vital role in shipping energy-saving emission reduction requirements issued by International Maritime Organization (IMO.

  3. 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.

  4. 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.

  5. Prediction of velocity and attitude of a yacht sailing upwind by computational fluid dynamics

    Directory of Open Access Journals (Sweden)

    Heebum Lee

    2016-01-01

    Full Text Available One of the most important factors in sailing yacht design is accurate velocity prediction. Velocity prediction programs (VPP's are widely used to predict velocity of sailing yachts. VPP's, which are primarily based on experimental data and experience of long years, however suffer limitations when applied in realistic conditions. Thus, in the present study, a high fidelity velocity prediction method using computational fluid dynamics (CFD was proposed. Using the developed method, velocity and attitude of a 30 feet sloop yacht, which was developed by Korea Research Institute of Ship and Ocean (KRISO and termed KORDY30, were predicted in upwind sailing condition.

  6. Economic feasibility of sail power devices on Great Lakes bulk carriers

    Energy Technology Data Exchange (ETDEWEB)

    None

    1982-09-22

    Three ships were examined, the ED RYERSON, the ST. CLAIR, and the STEWART CORT to determine if retro-fitting these ships with a 3000 sq ft soft sail cat rig is economically feasible. By using existing weather data taken from recorded observations on Lake Michigan and Lake Superior and known performance characteristics of both the sailplan and hull, a computer program was written to model the problem. Three cases for each ship were estimated. The first was the average fuel savings, second was an optimistic estimate of fuel savings, and the third was a pessimistic estimate of fuel savings. Several considerations had to be taken into account that had serious consequences for the economic viability of the idea. One was the fact that all of the aforementioned ships have self unloading equipment that require about 80% of the deck space to be clear. This limited the choice of sailplans to one per ship. Another consideration is that due to bridge clearance problems an air draft of less than 125' was required. These two factors limited the size and efficiency of the sail plan. The third consideration is that due to the very tight shipping channels on the Great Lakes, there is no provision for altering course to take advantage of prevailing winds in order to maximize the usefulness of the sail device. The sail device on the ED RYERSON does not seem to be economically feasible. Even at the lowest interest rate investigated in this study (8%) the average annual cost improves only in the optimistic estimates. At 12% interest even this slight advantage disappears. The sail devices on the STEWART CORT and ST. CLAIR seem to be marginally feasible at low interest rates and the present cost of fuel. The STEWART CORT seems to benefit most from the fitting of a sail device. A modest increase in fuel prices, perhaps possible, will make both of these ships look substantially better.

  7. 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

  8. Physical requirements in Olympic sailing

    DEFF Research Database (Denmark)

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

    2015-01-01

    Abstract Physical fitness and muscular strength are important performance parameters in Olympic sailing although their relative importance changes between classes. The Olympic format consists of eight yacht types combined into 10 so-called events with total 15 sailors (male and female) in a compl...... to yacht types, and reviews the existing knowledge on physical requirements in modern Olympic sailing. Finally, recommendations for future research in sailing are given.......Abstract Physical fitness and muscular strength are important performance parameters in Olympic sailing although their relative importance changes between classes. The Olympic format consists of eight yacht types combined into 10 so-called events with total 15 sailors (male and female......) 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...

  9. Relativistic solar sails

    Science.gov (United States)

    Güémez, J.; Fiolhais, M.

    2018-05-01

    We apply the four-vector formalism of special relativity to describe various interaction processes of photons with a solar sail, in two cases: when the sail’s surface is a perfect mirror, and when it is a body coated with a totally absorbing material. We stress the pedagogical value of implementing simultaneously both the linear momentum and the energy conservation in a covariant fashion, as our formalism inherently does. It also allows for a straightforward change of the description of a certain process in different inertial reference frames.

  10. "Light sail" acceleration reexamined.

    Science.gov (United States)

    Macchi, Andrea; Veghini, Silvia; Pegoraro, Francesco

    2009-08-21

    The dynamics of the acceleration of ultrathin foil targets by the radiation pressure of superintense, circularly polarized laser pulses is investigated by analytical modeling and particle-in-cell simulations. By addressing self-induced transparency and charge separation effects, it is shown that for "optimal" values of the foil thickness only a thin layer at the rear side is accelerated by radiation pressure. The simple "light sail" model gives a good estimate of the energy per nucleon, but overestimates the conversion efficiency of laser energy into monoenergetic ions.

  11. 'Light Sail' Acceleration Reexamined

    International Nuclear Information System (INIS)

    Macchi, Andrea; Veghini, Silvia; Pegoraro, Francesco

    2009-01-01

    The dynamics of the acceleration of ultrathin foil targets by the radiation pressure of superintense, circularly polarized laser pulses is investigated by analytical modeling and particle-in-cell simulations. By addressing self-induced transparency and charge separation effects, it is shown that for 'optimal' values of the foil thickness only a thin layer at the rear side is accelerated by radiation pressure. The simple 'light sail' model gives a good estimate of the energy per nucleon, but overestimates the conversion efficiency of laser energy into monoenergetic ions.

  12. Investigation of the Airflow around a Sail.

    Science.gov (United States)

    Gray, Rachel P.

    1986-01-01

    Shows how air flows around a sail, explaining why a dinghy is able to move toward the wind rather than be blown backwards. Also illustrates the effects of alternating the angle of a sail, using different sail shapes and using a rig consisting of two sails. (JN)

  13. Competitive Liner Shipping Network Design

    DEFF Research Database (Denmark)

    Karsten, Christian Vad; Brouer, Berit Dangaard; Pisinger, David

    2017-01-01

    We present a solution method for the liner shipping network design problem which is a core strategic planning problem faced by container carriers. We propose the first practical algorithm which explicitly handles transshipment time limits for all demands. Individual sailing speeds at each service...... 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...

  14. Competitive Liner Shipping Network Design

    DEFF Research Database (Denmark)

    Karsten, Christian Vad; Brouer, Berit Dangaard; Pisinger, David

    We present a solution method for the liner shipping network design problem which is a core strategic planning problem faced by container carriers. We propose the first practical algorithm which explicitly handles transshipment time limits for all demands. Individual sailing speeds at each service...... leg are used to balance sailings 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...

  15. Safety of nuclear ships

    International Nuclear Information System (INIS)

    1978-01-01

    analysed. Three separate sessions were devoted to legal, licensing and port entry considerations. The participants discussed the legal aspects of sailing of nuclear merchant ships. Lawyers, members of nuclear ship crews, and members of port authorities discussed their past experience with the 'SAVANNAH' and 'OTTO HAHN', when each port entry had had to be negotiated at a high governmental level. The urgent need for internationally acceptable documents concerning the safety of nuclear ships and legal responsibilities in the case of accidents with nuclear ships were stressed

  16. 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.

  17. Relativistic Light Sails

    International Nuclear Information System (INIS)

    Kipping, David

    2017-01-01

    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. System identification and the modeling of sailing yachts

    Science.gov (United States)

    Legursky, Katrina

    yaw. Existing aerodynamic models for sailing yachts are unsuitable for control system design as they do not include a physical description of the sails' dynamic effect on the system. A new aerodynamic model is developed and validated using the full-scale sailing data which includes sail deflection as a control input to the system. The Maximum Likelihood Estimation (MLE) algorithm is used with non-linear simulation data to successfully estimate a set of hydrodynamic derivatives for a sailing yacht. It is shown that all sailing yacht models will contain a second order mode (referred to herein as Mode 1A.S or 4B.S) which is dependent upon trimmed roll angle. For the test yacht it is concluded that for this mode when the trimmed roll angle is, roll rate and roll angle are the dominant motion variables, and for surge velocity and yaw rate dominate. This second order mode is dynamically stable for . It transitions from stability in the higher values of to instability in the region defined by. These conclusions align with other work which has also found roll angle to be a driving factor in the dynamic behavior of a tall-ship (Johnson, Miles, Lasher, & Womack, 2009). It is also shown that all linear models also contain a first order mode, (referred to herein as Mode 3A.F or 1B.F), which lies very close to the origin of the complex plane indicating a long time constant. Measured models have indicated this mode can be stable or unstable. The eigenvector analysis reveals that the mode is stable if the surge contribution is 20%. The small set of maneuvers necessary for model identification, quick OSLS estimation method, and detailed modal analysis of estimated models outlined in this work are immediately applicable to existing autonomous mono-hull sailing yachts, and could readily be adapted for use with other wind-powered vessel configurations such as wing-sails, catamarans, and tri-marans. (Abstract shortened by UMI.)

  19. Status of solar sail technology within NASA

    Science.gov (United States)

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

    2011-12-01

    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. NASA has successfully completed functional vacuum testing in their Glenn Research Center's Space Power Facility at Plum Brook Station, Ohio. The sails were designed and developed by Alliant Techsystems Space Systems and L'Garde, respectively. The sail systems consist of a central structure with four deployable booms that support each sail. These sail designs are robust enough for deployment in a one-atmosphere, one-gravity environment and are scalable to much larger solar sails - perhaps as large as 150 m on a side. Computation modeling and analytical simulations were performed in order to assess the scalability of the technology to the larger sizes that are required to implement the first generation of missions using solar sails. Furthermore, life and space environmental effects testing of sail and component materials was 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 $30 M investment made in solar sail technology to that point, NASA Marshall Space Flight Center funded the NanoSail-D, a subscale solar sail system designed for possible small spacecraft applications. The NanoSail-D mission flew on board a Falcon-1 rocket, launched August 2, 2008. As a result of the failure of that rocket, the NanoSail-D was never successfully given the opportunity to achieve orbit. The NanoSail-D flight spare was flown in the Fall of 2010. This review paper summarizes NASA's investment in solar sail technology to date and discusses future opportunities.

  20. Comparison of two mathematical models of the kite for Laddermill sail simulation

    NARCIS (Netherlands)

    Podgaets, A.R.; Ockels, W.J.

    2007-01-01

    Laddermill sail is an innovative approach to propel the ship with the power generated by kites. The first Laddermill system is currently being designed however existing mathematical models of the system produce different optimal recommendations. Thus a decision has been made to step back and to take

  1. SailSpy: a vision system for yacht sail shape measurement

    Science.gov (United States)

    Olsson, Olof J.; Power, P. Wayne; Bowman, Chris C.; Palmer, G. Terry; Clist, Roger S.

    1992-11-01

    SailSpy is a real-time vision system which we have developed for automatically measuring sail shapes and masthead rotation on racing yachts. Versions have been used by the New Zealand team in two America's Cup challenges in 1988 and 1992. SailSpy uses four miniature video cameras mounted at the top of the mast to provide views of the headsail and mainsail on either tack. The cameras are connected to the SailSpy computer below deck using lightweight cables mounted inside the mast. Images received from the cameras are automatically analyzed by the SailSpy computer, and sail shape and mast rotation parameters are calculated. The sail shape parameters are calculated by recognizing sail markers (ellipses) that have been attached to the sails, and the mast rotation parameters by recognizing deck markers painted on the deck. This paper describes the SailSpy system and some of the vision algorithms used.

  2. 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

  3. 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.

  4. A Global Approach for the Design of a Rim- Driven Marine Turbine Generator for Sail Boat

    OpenAIRE

    DROUEN, Laurent; CHARPENTIER, Jean-Frederic; SEMAIL, Eric; CLENET, Stéphane; SEMAIL, Eric

    2012-01-01

    International audience; Development of new ways to provide clean onboard electric energy is a key feature for the sailing boat industry and sail race teams. This is why marine turbines (MT), are considered to provide onboard energy. These turbines can be used to harness kinetic energy of the water flow related to the ship motion. In this paper we propose to study an unconventional design of such a turbine where the electrical generator is located in the periphery of the blades and where the m...

  5. 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

  6. Sail Training: A Systematic Review

    Science.gov (United States)

    Manu Schijf; Allison, Pete; Von Wald, Kris

    2017-01-01

    Starting around 2000, research activity about sail training increased such that there is now sufficient research on the subject to constitute a foundation upon which an emerging body of literature can be identified. The literature has the potential to be utilized to influence program design, policy, theory, and practice--a growing area of youth…

  7. 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.

  8. Flying on Sun Shine: Sailing in Space

    International Nuclear Information System (INIS)

    Alhorn, Dean

    2012-01-01

    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.

  9. NASA Solar Sail Propulsion Technology Development

    Science.gov (United States)

    Johnson, Les; Montgomery, Edward E.; Young, Roy; Adams, Charles

    2007-01-01

    NASA's In-Space Propulsion Technology Program has developed the first generation of solar sail propulsion systems sufficient to accomplish inner solar system science and exploration missions. These first generation solar sails, when operational, will range in size from 40 meters to well over 100 meters in diameter and have an areal density of less than 13 grams per square meter. A rigorous, multi-year technology development effort culminated in 2005 with the testing of two different 20-m solar sail systems under thermal vacuum conditions. The first system, developed by ATK Space Systems of Goleta, California, uses rigid booms to deploy and stabilize the sail. In the second approach, L'Garde, Inc. of Tustin, California uses inflatable booms that rigidize in the coldness of space to accomplish sail deployment. This effort provided a number of significant insights into the optimal design and expected performance of solar sails as well as an understanding of the methods and costs of building and using them. In a separate effort, solar sail orbital analysis tools for mission design were developed and tested. Laboratory simulations of the effects of long-term space radiation exposure were also conducted on two candidate solar sail materials. Detailed radiation and charging environments were defined for mission trajectories outside the protection of the earth's magnetosphere, in the solar wind environment. These were used in other analytical tools to prove the adequacy of sail design features for accommodating the harsh space environment. Preceding and in conjunction with these technology efforts, NASA sponsored several mission application studies for solar sails. Potential missions include those that would be flown in the near term to study the sun and be used in space weather prediction to one that would use an evolved sail capability to support humanity's first mission into nearby interstellar space. This paper will describe the status of solar sail propulsion within

  10. The Ship of Classics: The Ark, the Titanic, or the Good Ship Lollipop?

    Science.gov (United States)

    Wolverton, Robert E.

    Various problems confronting teachers of the classics are explored through frequent reference to the metaphor of the classics viewed as a sailing ship in a sea of troubled waters. Several of the difficulties confronting classics teachers are seen to be related to an anti-intellectual mood prevailing in academe, scheduling problems, shifting school…

  11. Steering Concept of a 2-Blade Heliogyro Solar Sail Spacecraft

    Science.gov (United States)

    Wiwattananon, Peerawan; Bryant, Robert G.

    2017-01-01

    Solar sails can be classified into two groups based on their method of stabilization: 1) truss supported, and 2) centrifugally (spin) supported. The truss configuration requires masts or booms to deploy, support, and rigidize the sails whereas the spin type uses the spacecraft’s centrifugal force to deploy and stabilize the sails. The truss-supported type sail has a scaling limitation because as the sail area gets larger, the sail is increasingly more difficult to make and stow: the masts and booms get heavier, occupying more volume, and have increased risk during deployment. This major disadvantage limits the size of the sail area. The spin type comes in two configurations: 1) spinning square/disk sail and 2) heliogyro sail. This spinning square/disk sail architecture suffers the same sail area limitation as the truss-supported sail.

  12. 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...

  13. 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...

  14. Developments of an Interactive Sail Design Method

    OpenAIRE

    S. M. Malpede; M. Vezza

    2000-01-01

    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 dis...

  15. Comprehensive Solar Sail Simulation, Phase I

    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. Solar Sail Propulsion Technology at NASA

    Science.gov (United States)

    Johnson, Charles Les

    2007-01-01

    NASA's In-Space Propulsion Technology Program developed the first generation of solar sail propulsion systems sufficient to accomplish inner solar system science and exploration missions. These first generation solar sails, when operational, will range in size from 40 meters to well over 100 meters in diameter and have an area density of less than 13 grams per square meter. A rigorous, multi-year technology development effort culminated in 2005 with the testing of two different 20-m solar sail systems under thermal vacuum conditions. This effort provided a number of significant insights into the optimal design and expected performance of solar sails as well as an understanding of the methods and costs of building and using them. In addition, solar sail orbital analysis tools for mission design were developed and tested. Laboratory simulations of the effects of long-term space radiation exposure were also conducted on two candidate solar sail materials. Detailed radiation and charging environments were defined for mission trajectories outside the protection of the earth's magnetosphere, in the solar wind environment. These were used in other analytical tools to prove the adequacy of sail design features for accommodating the harsh space environment. The presentation will describe the status of solar sail propulsion within NASA, near-term solar sail mission applications, and near-term plans for further development.

  17. The economic potential of a cassette-type-reactor-installed nuclear ice-breaking container ship

    International Nuclear Information System (INIS)

    Kondo, Koichi; Takamasa, Tomoji

    1999-01-01

    An improved cassette-type marine reactor MRX (Marine Reactor X) which is currently researched and developed by the Japan Atomic Energy Research Institute is designed to be easily removed and transferred to another ship. If the reactor in a nuclear-powered ship, which is the reason for its higher cost, were replaced by the cassette-type-MRX, the reusability of the MRX would reduce the cost difference between nuclear-powered and diesel ships. As an investigation of one aspect of a cassette-type MRX, we attempted in this study to do an economic review of an MRX-installed nuclear-powered ice-breaking container ship sailing via the Arctic Ocean. The transportation cost between the Far East and Europe to carry one TEU (twenty-foot-equivalent container unit) over the entire life of the ship for an MRX (which is used for a 20-year period)-installed container ship sailing via the Arctic Ocean is about 70% higher than the Suez Canal diesel ship, carrying 8,000 TEU and sailing at 25 knots, and about 10% higher than the Suez Canal diesel ship carrying 4,000 TEU and sailing at 34 knots. The cost for a cassette-type-MRX (which is used for a 40-year period, removed and transferred to a second ship after being used for 20 years in the first ship)-installed nuclear-powered container ship is about 7% lower than that for the one operated for 20 years. Considering any loss or reduction in sales opportunities through the extension of the transportation period, the nuclear-powered container ship via the Arctic Sea is a more suitable means of transportation than a diesel ship sailing at 25 knots via the Suez Canal when the value of the commodities carried exceeds 2,800 dollars per freight ton. (author)

  18. Economic potential of nuclear-powered ice-breaking container ship via the northern sea route

    International Nuclear Information System (INIS)

    Takamasa, Tomoji; Kondo, Koichi

    2000-01-01

    An improved cassette-type marine reactor MRX (Marine Reactor X) which is currently researched and developed by the JAERI is designed to be easily removed and transferred to another ship. If the reactor in a nuclear-powered ship, which is the reason for its higher cost, were replaced by the cassette-type-MRX, the reusability of the MRX would reduce the cost difference between nuclear-powered and diesel ships. As an investigation of one aspect of a cassette-type MRX, we attempted in this study to do an economic review of an MRX-installed nuclear-powered ice-breaking container ship sailing via the Arctic Ocean. The transportation cost between the Far East and Europe to carry one TEU (twenty-foot-equivalent container unit) over the entire life of the ship for an MRX (which is used for a 20-year period)-installed container ship sailing via the Arctic Ocean is about 70% higher than the Suez Canal diesel ship, carrying 8,000 TEU and sailing at 25 knots, and about 10% higher than the Suez Canal diesel ship carrying 4,000 TEU and sailing at 34 knots. The cost for a cassette-type-MRX (which is used for a 40-year period, removed and transferred to a second ship after being used for 20 years in the first ship)-installed nuclear-powered container ship is about 7% lower than that for the one operated for 20 years. Considering any loss or reduction in sales opportunities through the extension of the transportation period, the nuclear-powered container ship via the Arctic Sea is a more suitable means of transportation than a diesel ship sailing at 25 knots via the Suez Canal when the value of the commodities carried exceeds 2,800 dollars per freight ton. (author)

  19. CFD simulation of two-sail interaction about a sailing yacht; Sailing Yacht no niyoku kansho no CFD simulation

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Y.; Miyata, H.; Sato, T. [The University of Tokyo, Tokyo (Japan). Faculty of Engineering

    1997-06-01

    Numerical analysis of sail characteristics was done by the finite volume method for an IACC class racing yacht, in compliance to the WISDAM-7 method for analyzing flow fields around the hull. The simulation code makes discrete the Navier-Stokes equation for non-compressive fluid in a conserved system by the finite volume method, and tries to find the solutions following the algorithm of the MAC method in a time-dependent manner. The H-H grids generated by an interface boundary technique for each sail are integrated for the two-sail configuration. It is found that combination of the finite volume method and grid integration is an adequate CFD procedure for simulation of interactions between the two sails. Performance of two-sail configuration, involving complex mechanisms such as interactions and separation of flows, is found by the method in which viscosity is taken into consideration. 5 refs., 20 figs., 3 tabs.

  20. PPI, paradoxes and Plato: who's sailing the ship?

    Science.gov (United States)

    Ives, Jonathan; Damery, Sarah; Redwod, Sabi

    2013-03-01

    Over the last decade, patient and public involvement (PPI) has become a requisite in applied health research. Some funding bodies demand explicit evidence of PPI, while others have made a commitment to developing PPI in the projects they fund. Despite being commonplace, there remains a dearth of engagement with the ethical and theoretical underpinnings of PPI processes and practices. More specifically, while there is a small (but growing) body of literature examining the effectiveness and impact of PPI, there has been relatively little reflection on whether the concept/practice of PPI is internally coherent. Here, the authors unpick a 'paradox' within PPI, which highlights a tension between its moral and pragmatic motivations and its implementation. The authors argue that this 'professionalisation paradox' means we need to rethink the practice, and purpose, of PPI in research.

  1. Environmental Impacts of Shipping to and from Citronen Fjord

    DEFF Research Database (Denmark)

    Boertmann, D.

    . The waters off Citronen Fjord are covered by ice throughout the year. Fast ice covers Frederick E. Hyde Fjord and the coastal waters off the outer coast, and pack ice covers the Wandel Sea and the majority of the Greenland Sea. Sailing in these waters will require powerful icebreaking capabilities...... Henrik Krøyer Holme are the most sensitive to sailing and icebreaking. Sailing and icebreaking in these areas should be avoided. The movement of icebreakers through the fast ice of Frederick E. Hyde Fjord may alter the habitat of a population of ringed seals that inhabit the fiord. Incidental oil spills...... from the ships sailing to and from Citronen Fjord poses the most serious threats to the wildlife in the area covered by this report....

  2. 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...

  3. 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.

  4. The formation of ice sails

    Science.gov (United States)

    Fowler, A. C.; Mayer, C.

    2017-11-01

    Debris-covered glaciers are prone to the formation of a number of supraglacial geomorphological features, and generally speaking, their upper surfaces are far from level surfaces. Some of these features are due to radiation screening or enhancing properties of the debris cover, but theoretical explanations of the consequent surface forms are in their infancy. In this paper we consider a theoretical model for the formation of "ice sails", which are regularly spaced bare ice features which are found on debris-covered glaciers in the Karakoram.

  5. Validation of Solar Sail Simulations for the NASA Solar Sail Demonstration Project

    Science.gov (United States)

    Braafladt, Alexander C.; Artusio-Glimpse, Alexandra B.; Heaton, Andrew F.

    2014-01-01

    NASA's Solar Sail Demonstration project partner L'Garde is currently assembling a flight-like sail assembly for a series of ground demonstration tests beginning in 2015. For future missions of this sail that might validate solar sail technology, it is necessary to have an accurate sail thrust model. One of the primary requirements of a proposed potential technology validation mission will be to demonstrate solar sail thrust over a set time period, which for this project is nominally 30 days. This requirement would be met by comparing a L'Garde-developed trajectory simulation to the as-flown trajectory. The current sail simulation baseline for L'Garde is a Systems Tool Kit (STK) plug-in that includes a custom-designed model of the L'Garde sail. The STK simulation has been verified for a flat plate model by comparing it to the NASA-developed Solar Sail Spaceflight Simulation Software (S5). S5 matched STK with a high degree of accuracy and the results of the validation indicate that the L'Garde STK model is accurate enough to meet the potential future mission requirements. Additionally, since the L'Garde sail deviates considerably from a flat plate, a force model for a non-flat sail provided by L'Garde sail was also tested and compared to a flat plate model in S5. This result will be used in the future as a basis of comparison to the non-flat sail model being developed for STK.

  6. Nonlinear Container Ship Model for the Study of Parametric Roll Resonance

    DEFF Research Database (Denmark)

    Holden, Christian; Galeazzi, Roberto; Rodríguez, Claudio

    2007-01-01

    Parametric roll is a critical phenomenon for ships, whose onset may cause roll oscillations up to 40, leading to very dangerous situations and possibly capsizing. Container ships have been shown to be particularly prone to parametric roll resonance when they are sailing in moderate to heavy head ...

  7. Full-shipload tramp ship routing and scheduling with variable speeds

    DEFF Research Database (Denmark)

    Wen, M.; Røpke, Stefan; Petersen, Hanne Løhmann

    2016-01-01

    This paper investigates the simultaneous optimization problem of routing and sailing speed in the context of full-shipload tramp shipping. In this problem, a set of cargoes can be transported from their load to discharge ports by a fleet of heterogeneous ships of different speed ranges and load......-dependent fuel consumption. The objective is to determine which orders to serve and to find the optimal route for each ship and the optimal sailing speed on each leg of the route so that the total profit is maximized. The problem originated from a real-life challenge faced by a Danish tramp shipping company....... It is shown that speed optimization can improve the total profit by 16% on average and the fuel price has a significant effect on the average sailing speed and total profit....

  8. Development of an upwind sailing ergometer.

    Science.gov (United States)

    Callewaert, Margot; Geerts, Stefan; Lataire, Evert; Boone, Jan; Vantorre, Marc; Bourgois, Jan

    2013-11-01

    To develop a sailing ergometer that accurately simulates upwind sailing exercise. A sailing ergometer that measures roll moment accompanied by a biofeedback system that allows imposing a certain quasi-isometric upwind sailing protocol (ie, 18 bouts of 90-s hiking at constantly varying hiking intensity interspersed with 10 s to tack) was developed. Ten male high-level Laser sailors performed an incremental cycling test (ICT; ie, step protocol at 80 W + 40 W/3 min) and an upwind sailing test (UST). During both, heart rate (HR), oxygen uptake (VO(2)), ventilation (V(E)), respiratory-exchange ratio, and rating of perceived exertion were measured. During UST, also the difference between the required and produced hiking moment (HM) was calculated as error score (ES). HR, VO(2), and V(E) were calculated relative to their peak values determined during ICT. After UST, the subjects were questioned about their opinion on the resemblance between this UST and real-time upwind sailing. An average HM of 89.0% ± 2.2% HM(max) and an average ES of 4.1% ± 1.8% HM(max) were found. Mean HR, VO(2), and V(E) were, respectively, 80% ± 4% HR(peak), 39.5% ± 4.5% VO(2peak), and 30.3% ± 3.7% VE(peak). Both HM and cardiorespiratory values appear to be largely comparable to literature reports during on-water upwind sailing. Moreover, the subjects gave the upwind sailing ergometer a positive resemblance score. Results suggest that this ergometer accurately simulates on-water upwind sailing exercise. As such, this ergometer could be a great help in performance diagnostics and training follow-up.

  9. Wave Height Distribution Observed by Ships in the North Atlantic

    DEFF Research Database (Denmark)

    Olsen, Anders Smærup; Schrøter, Carsten; Jensen, Jørgen Juncher

    2005-01-01

    for the significant wave height, the relative speed and the ship heading relative to the wave direction is given. This distribution shows that for higher waves the crews avoid sailing in following sea and as expected the speed is decreased in higher waves. There is, however, still a relatively high probability...

  10. 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...

  11. Sunken ships and a long-lost port

    Digital Repository Service at National Institute of Oceanography (India)

    Tripati, S.; Sundaresh.; Gaur, A; Vora, K.H.

    armed Portuguese sailing ship, went down at Sunchi Reef about 400 years ago; the second vessel, carrying cargo for a Basel mission company based in India, went down at St. George’s Reef, either in 1865 or some time thereafter. What goods where...

  12. We'd rather be solar sailing

    Science.gov (United States)

    Kuznik, Frank

    1994-06-01

    On 4 Feb. 1993 a solar sail that traveled piggyback on a Progress resupply rocket to the Mir Space Station was deployed after undocking from the Mir. It was the first sun-propelled spacecraft, and it attempted to reflect a patch of sunlight onto the night side of Earth, but wasn't very successful because of extensive cloud cover. Solar sail technology and its historical development are briefly discussed. NASA'a views and the World Space Foundation's involvement in solar sail development are presented.

  13. 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.

  14. Solarelastic Stability of Solar Sail Structures

    Data.gov (United States)

    National Aeronautics and Space Administration — In order to avoid an unintended failure in proposed Solar Sail spacecraft due to solarelastic interactions it is important to develop an analytical framework for...

  15. 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.

  16. Solar Sails: Sneaking up on Interstellar Travel

    Science.gov (United States)

    Johnson, L.

    Throughout the world, government agencies, universities and private companies are developing solar sail propulsion systems to more efficiently explore the solar system and to enable science and exploration missions that are simply impossible to accomplish by any other means. Solar sail technology is rapidly advancing to support these demonstrations and missions, and in the process, is incrementally advancing one of the few approaches allowed by physics that may one day take humanity to the stars. Continuous solar pressure provides solar sails with propellantless thrust, potentially enabling them to propel a spacecraft to tremendous speeds ­ theoretically much faster than any present-day propulsion system. The next generation of sails will enable us to take our first real steps beyond the edge of the solar system, sending spacecraft out to distances of 1000 Astronomical Units, or more. In the farther term, the descendants of these first and second generation sails will augment their thrust by using high power lasers and enable travel to nearby stellar systems with flight times less than 500 years ­ a tremendous improvement over what is possible with conventional chemical rockets. By fielding these first solar sail systems, we are sneaking up on a capability to reach the stars.

  17. Multiple NEO Rendezvous Using Solar Sail Propulsion

    Science.gov (United States)

    Johnson, Les; Alexander, Leslie; Fabisinski, Leo; Heaton, Andy; Miernik, Janie; Stough, Rob; Wright, Roosevelt; Young, Roy

    2012-01-01

    The NASA Marshall Space Flight Center (MSFC) Advanced Concepts Office performed an assessment of the feasibility of using a near-term solar sail propulsion system to enable a single spacecraft to perform serial rendezvous operations at multiple Near Earth Objects (NEOs) within six years of launch on a small-to-moderate launch vehicle. The study baselined the use of the sail technology demonstrated in the mid-2000 s by the NASA In-Space Propulsion Technology Project and is scheduled to be demonstrated in space by 2014 as part of the NASA Technology Demonstration Mission Program. The study ground rules required that the solar sail be the only new technology on the flight; all other spacecraft systems and instruments must have had previous space test and qualification. The resulting mission concept uses an 80-m X 80-m 3-axis stabilized solar sail launched by an Athena-II rocket in 2017 to rendezvous with 1999 AO10, Apophis and 2001 QJ142. In each rendezvous, the spacecraft will perform proximity operations for approximately 30 days. The spacecraft science payload is simple and lightweight; it will consist of only the multispectral imager flown on the Near Earth Asteroid Rendezvous (NEAR) mission to 433 Eros and 253 Mathilde. Most non-sail spacecraft systems are based on the Messenger mission spacecraft. This paper will describe the objectives of the proposed mission, the solar sail technology to be employed, the spacecraft system and subsystems, as well as the overall mission profile.

  18. 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.

  19. Solar Sail Propulsion Technology Readiness Level Database

    Science.gov (United States)

    Adams, Charles L.

    2004-01-01

    The NASA In-Space Propulsion Technology (ISPT) Projects Office has been sponsoring 2 solar sail system design and development hardware demonstration activities over the past 20 months. Able Engineering Company (AEC) of Goleta, CA is leading one team and L Garde, Inc. of Tustin, CA is leading the other team. Component, subsystem and system fabrication and testing has been completed successfully. The goal of these activities is to advance the technology readiness level (TRL) of solar sail propulsion from 3 towards 6 by 2006. These activities will culminate in the deployment and testing of 20-meter solar sail system ground demonstration hardware in the 30 meter diameter thermal-vacuum chamber at NASA Glenn Plum Brook in 2005. This paper will describe the features of a computer database system that documents the results of the solar sail development activities to-date. Illustrations of the hardware components and systems, test results, analytical models, relevant space environment definition and current TRL assessment, as stored and manipulated within the database are presented. This database could serve as a central repository for all data related to the advancement of solar sail technology sponsored by the ISPT, providing an up-to-date assessment of the TRL of this technology. Current plans are to eventually make the database available to the Solar Sail community through the Space Transportation Information Network (STIN).

  20. The effects of Poynting–Robertson drag on solar sails

    Directory of Open Access Journals (Sweden)

    F.A. Abd El-Salam

    2018-06-01

    Full Text Available In the present work, the concept of solar sailing and its developing spacecraft are presented. The effects of Poynting–Robertson drag on solar sails are considered. Some analytical control laws with some mentioned input constraints for optimizing solar sails dynamics in heliocentric orbit using Lagrange’s planetary equations are obtained. Optimum force vector in a required direction is maximized by deriving optimal sail cone angle. New control laws that maximize thrust to obtain certain required maximization in some particular orbital element are obtained. Keywords: Poynting–Robertson drag, Solar sail, Control laws, Optimal sail, Cone angle

  1. 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...

  2. Isometric quadriceps strength determines sailing performance and neuromuscular fatigue during an upwind sailing emulation.

    Science.gov (United States)

    Bourgois, Jan G; Callewaert, Margot; Celie, Bert; De Clercq, Dirk; Boone, Jan

    2016-01-01

    This study investigates the physiological responses to upwind sailing on a laser emulation ergometer and analyses the components of the physical profile that determine the physiological responses related to sailing level. Ten male high-level laser sailors performed an upwind sailing test, incremental cycling test and quadriceps strength test. During the upwind sailing test, heart rate (HR), oxygen uptake, ventilation, respiratory exchange ratio, rating of perceived exertion (RPE) and lactate concentration were measured, combined with near-infrared spectroscopy (NIRS) and electromyography (EMG) registration of the M. Vastus lateralis. Repeated measures ANOVA showed for the cardio-respiratory, metabolic and muscles responses (mean power frequency [MPF], root mean square [RMS], deoxy[Hb+Mb]) during the upwind sailing test an initial significant increase followed by a stabilisation, despite a constant increase in RPE. Stepwise regression analysis showed that better sailing level was for 46.5% predicted by lower MPF decrease. Lower MPF decrease was for 57.8% predicted by a higher maximal isometric quadriceps strength. In conclusion, this study indicates that higher sailing level was mainly determined by a lower rate of neuromuscular fatigue during the upwind sailing test (as indicated by MPF decrease). Additionally, the level of neuromuscular fatigue was mainly determined by higher maximal isometric quadriceps strength stressing the importance of resistance training in the planning of training.

  3. 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…

  4. Model for Estimation of Fuel Consumption of Cruise Ships

    Directory of Open Access Journals (Sweden)

    Morten Simonsen

    2018-04-01

    Full Text Available This article presents a model to estimate the energy use and fuel consumption of cruise ships that sail Norwegian waters. Automatic identification system (AIS data and technical information about cruise ships provided input to the model, including service speed, total power, and number of engines. The model was tested against real-world data obtained from a small cruise vessel and both a medium and large cruise ship. It is sensitive to speed and the corresponding engine load profile of the ship. A crucial determinate for total fuel consumption is also associated with hotel functions, which can make a large contribution to the overall energy use of cruise ships. Real-world data fits the model best when ship speed is 70–75% of service speed. With decreased or increased speed, the model tends to diverge from real-world observations. The model gives a proxy for calculation of fuel consumption associated with cruise ships that sail to Norwegian waters and can be used to estimate greenhouse gas emissions and to evaluate energy reduction strategies for cruise ships.

  5. The effects of Poynting-Robertson drag on solar sails

    Science.gov (United States)

    Abd El-Salam, F. A.

    2018-06-01

    In the present work, the concept of solar sailing and its developing spacecraft are presented. The effects of Poynting-Robertson drag on solar sails are considered. Some analytical control laws with some mentioned input constraints for optimizing solar sails dynamics in heliocentric orbit using Lagrange's planetary equations are obtained. Optimum force vector in a required direction is maximized by deriving optimal sail cone angle. New control laws that maximize thrust to obtain certain required maximization in some particular orbital element are obtained.

  6. Laboratory Facility for Simulating Solar Wind Sails

    International Nuclear Information System (INIS)

    Funaki, Ikkoh; Ueno, Kazuma; Oshio, Yuya; Ayabe, Tomohiro; Horisawa, Hideyuki; Yamakawa, Hiroshi

    2008-01-01

    Magnetic sail (MagSail) is a deep space propulsion system, in which an artificial magnetic cavity captures the energy of the solar wind to propel a spacecraft in the direction leaving the sun. For a scale-model experiment of the plasma flow of MagSail, we employed a magnetoplasmadynamic arcjet as a solar wind simulator. It is observed that a plasma flow from the solar wind simulator reaches a quasi-steady state of about 0.8 ms duration after a transient phase when initiating the discharge. During this initial phase of the discharge, a blast-wave was observed to develop radially in a vacuum chamber. When a solenoidal coil (MagSail scale model) is immersed into the quasi-steady flow where the velocity is 45 km/s, and the number density is 10 19 m-3, a bow shock as well as a magnetic cavity were formed in front of the coil. As a result of the interaction between the plasma flow and the magnetic cavity, the momentum of the simulated solar wind is decreased, and it is found from the thrust measurement that the solar wind momentum is transferred to the coil simulating MagSail.

  7. Transformation of a wave energy spectrum from encounter to absolute domain when observing from an advancing ship

    DEFF Research Database (Denmark)

    Nielsen, Ulrik Dam

    2017-01-01

    directly in the encounter domain. The encounter domain is that observed from a ship when it advances in a seaway, whereas the absolute domain is that corresponding to making observations from a fixed point in the inertial frame. Spectrum transformation can be uniquely carried out if the ship sails ”against...

  8. Shipping Fairways

    Data.gov (United States)

    Department of Homeland Security — Various shipping zones delineate activities and regulations for marine vessel traffic. Traffic lanes define specific traffic flow, while traffic separation zones...

  9. Development of a Motion System for an Advanced Sailing Simulator

    NARCIS (Netherlands)

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

    2013-01-01

    To train competitive sailing in a virtual setting, motion of the boat as well as haptic feedback of the sail lines is essential. When discussing virtual environments (VEs) the concept of presence is often used. In this study we develop a sailing simulator motion system to research what factors

  10. Global ship accidents and ocean swell-related sea states

    Science.gov (United States)

    Zhang, Zhiwei; Li, Xiao-Ming

    2017-11-01

    With the increased frequency of shipping activities, navigation safety has become a major concern, especially when economic losses, human casualties and environmental issues are considered. As a contributing factor, the sea state plays a significant role in shipping safety. However, the types of dangerous sea states that trigger serious shipping accidents are not well understood. To address this issue, we analyzed the sea state characteristics during ship accidents that occurred in poor weather or heavy seas based on a 10-year ship accident dataset. Sea state parameters of a numerical wave model, i.e., significant wave height, mean wave period and mean wave direction, were analyzed for the selected ship accident cases. The results indicated that complex sea states with the co-occurrence of wind sea and swell conditions represent threats to sailing vessels, especially when these conditions include similar wave periods and oblique wave directions.

  11. Global ship accidents and ocean swell-related sea states

    Directory of Open Access Journals (Sweden)

    Z. Zhang

    2017-11-01

    Full Text Available With the increased frequency of shipping activities, navigation safety has become a major concern, especially when economic losses, human casualties and environmental issues are considered. As a contributing factor, the sea state plays a significant role in shipping safety. However, the types of dangerous sea states that trigger serious shipping accidents are not well understood. To address this issue, we analyzed the sea state characteristics during ship accidents that occurred in poor weather or heavy seas based on a 10-year ship accident dataset. Sea state parameters of a numerical wave model, i.e., significant wave height, mean wave period and mean wave direction, were analyzed for the selected ship accident cases. The results indicated that complex sea states with the co-occurrence of wind sea and swell conditions represent threats to sailing vessels, especially when these conditions include similar wave periods and oblique wave directions.

  12. Ship Vibrations

    DEFF Research Database (Denmark)

    Sørensen, Herman

    1997-01-01

    Methods for calculating natural frequencies for ship hulls and for plates and panels.Evaluation of the risk for inconvenient vibrations on board......Methods for calculating natural frequencies for ship hulls and for plates and panels.Evaluation of the risk for inconvenient vibrations on board...

  13. SAIL--stereo-array isotope labeling.

    Science.gov (United States)

    Kainosho, Masatsune; Güntert, Peter

    2009-11-01

    Optimal stereospecific and regiospecific labeling of proteins with stable isotopes enhances the nuclear magnetic resonance (NMR) method for the determination of the three-dimensional protein structures in solution. Stereo-array isotope labeling (SAIL) offers sharpened lines, spectral simplification without loss of information and the ability to rapidly collect and automatically evaluate the structural restraints required to solve a high-quality solution structure for proteins up to twice as large as before. This review gives an overview of stable isotope labeling methods for NMR spectroscopy with proteins and provides an in-depth treatment of the SAIL technology.

  14. 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...

  15. Ships on the sea are responsible for enormous emissions. A sea journey which is sooty...; Schiffe auf dem Meer sind fuer gewaltige Emissionen verantwortlich. Eine Seefahrt, die ist russig...

    Energy Technology Data Exchange (ETDEWEB)

    Muehleisen, Martin

    2012-03-15

    Since the conversion from sailing ships to steamships at the end of the 18th century, ships emit large amounts of sulfur, nitrogen oxides and soot into the air. Environment, passengers and residents of port cities constantly are exposed to health hazards. The conversion to environmentally friendly propulsion technology at the maritime shipping as well as the inland waterway transport is a tough process.

  16. 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.

  17. Multiple NEO Rendezvous Using Solar Sails

    Science.gov (United States)

    Johnson, Les; Alexander, Leslie; Fabisinski, Leo; Heaton, Andy; Miernik, Janie; Stough, Rob; Wright, Roosevelt; Young, Roy

    2012-01-01

    Mission concept is to assess the feasibility of using solar sail propulsion to enable a robotic precursor that would survey multiple Near Earth Objects (NEOs) for potential future human visits. Single spacecraft will rendezvous with and image 3 NEOs within 6 years of launch

  18. Sails and norm minima of lattices

    International Nuclear Information System (INIS)

    German, O N

    2005-01-01

    It is known that a real number is badly approximable if and only if its partial quotients are uniformly bounded. In this paper an analogous assertion is proved for the so-called sails, which is one of the most natural multidimensional generalizations of continued fractions.

  19. 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.

  20. Test Ship

    Data.gov (United States)

    Federal Laboratory Consortium — The U. S. Navy dedicated the decommissioned Spruance Class destroyer ex-PAUL F. FOSTER (EDD 964), Test Ship, primarily for at sea demonstration of short range weapon...

  1. 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

  2. Solar Sail Material Performance Property Response to Space Environmental Effects

    Science.gov (United States)

    Edwards, David L.; Semmel, Charles; Hovater, Mary; Nehls, Mary; Gray, Perry; Hubbs, Whitney; Wertz, George

    2004-01-01

    The National Aeronautics and Space Administration's (NASA) Marshall Space Flight Center (MSFC) continues research into the utilization of photonic materials for spacecraft propulsion. Spacecraft propulsion, using photonic materials, will be achieved using a solar sail. A solar sail operates on the principle that photons, originating from the sun, impart pressure to the sail and therefore provide a source for spacecraft propulsion. The pressure imparted to a solar sail can be increased, up to a factor of two, if the sun-facing surface is perfectly reflective. Therefore, these solar sails are generally composed of a highly reflective metallic sun-facing layer, a thin polymeric substrate and occasionally a highly emissive back surface. Near term solar sail propelled science missions are targeting the Lagrange point 1 (Ll) as well as locations sunward of L1 as destinations. These near term missions include the Solar Polar Imager and the L1 Diamond. The Environmental Effects Group at NASA s Marshall Space Flight Center (MSFC) continues to actively characterize solar sail material in preparation for these near term solar sail missions. Previous investigations indicated that space environmental effects on sail material thermo-optical properties were minimal and would not significantly affect the propulsion efficiency of the sail. These investigations also indicated that the sail material mechanical stability degrades with increasing radiation exposure. This paper will further quantify the effect of space environmental exposure on the mechanical properties of candidate sail materials. Candidate sail materials for these missions include Aluminum coated Mylar[TM], Teonex[TM], and CPl (Colorless Polyimide). These materials were subjected to uniform radiation doses of electrons and protons in individual exposures sequences. Dose values ranged from 100 Mrads to over 5 Grads. The engineering performance property responses of thermo-optical and mechanical properties were

  3. Space Environmental Effects on Candidate Solar Sail Materials

    Science.gov (United States)

    Edwards, David L.; Nehls, Mary; Semmel, Charles; Hovater, Mary; Gray, Perry; Hubbs, Whitney; Wertz, George

    2004-01-01

    The National Aeronautics and Space Administration's (NASA) Marshall Space Flight Center (MSFC) continues research into the utilization of photonic materials for spacecraft propulsion. Spacecraft propulsion, using photonic materials, will be achieved using a solar sail. A solar sail operates on the principle that photons, originating from the sun, impart pressure to the sail and therefore provide a source for spacecraft propulsion. The pressure imparted ot a solar sail can be increased, up to a factor of two, if the sun-facing surface is perfectly reflective. Therefore, these solar sails are generally composed of a highly reflective metallic sun-facing layer, a thin polymeric substrate and occasionally a highly emissive back surface. Near term solar sail propelled science missions are targeting the Lagrange point 1 (L1) as well as locations sunward of L1 as destinations. These near term missions include the Solar Polar Imager and the L1 Diamond. The Environmental Effects Group at NASA's Marshall Space Flight Center (MSFC) continues to actively characterize solar sail material in preparation for these near term solar sail missions. Previous investigations indicated that space environmental effects on sail material thermo-optical properties were minimal and would not significantly affect the propulsion efficiency of the sail. These investigations also indicated that the sail material mechanical stability degrades with increasing radiation exposure. This paper will further quantify the effect of space environmental exposure on the mechanical properties of candidate sail materials. Candidate sail materials for these missions include Aluminum coated Mylar, Teonex, and CP1 (Colorless Polyimide). These materials were subjected to uniform radiation doses of electrons and protons in individual exposures sequences. Dose values ranged from 100 Mrads to over 5 Grads. The engineering performance property responses of thermo-optical and mechanical properties were characterized

  4. Ships - inspiring objects in architecture

    Science.gov (United States)

    Marczak, Elzbieta

    2017-10-01

    Sea-going vessels have for centuries fascinated people, not only those who happen to work at sea, but first and foremost, those who have never set foot aboard a ship. The environment in which ships operate is reminiscent of freedom and countless adventures, but also of hard and interesting maritime working life. The famous words of Pompey: “Navigare necesseest, vivere non estnecesse” (sailing is necessary, living - is not necessary), which he pronounced on a stormy sea voyage, arouse curiosity and excitement, inviting one to test the truth of this saying personally. It is often the case, however, that sea-faring remains within the realm of dreams, while the fascination with ships demonstrates itself through a transposition of naval features onto land constructions. In such cases, ship-inspired motifs bring alive dreams and yearnings as well as reflect tastes. Tourism is one of the indicators of people’s standard of living and a measure of a society’s civilisation. Maritime tourism has been developing rapidly in recent decades. A sea cruise offers an insight into life at sea. Still, most people derive their knowledge of passenger vessels and their furnishings from the mass media. Passenger vessels, also known as “floating cities,” are described as majestic and grand, while their on-board facilities as luxurious, comfortable, exclusive and inaccessible to common people on land. Freight vessels, on the other hand, are described as enormous objects which dwarf the human being into insignificance. This article presents the results of research intended to answer the following questions: what makes ships a source of inspiration for land architecture? To what extent and by what means do architects draw on ships in their design work? In what places can we find structures inspired by ships? What ships inspire architects? This article presents examples of buildings, whose design was inspired by the architecture and structural details of sea vessels. An analysis of

  5. Review of the total system related to operation of nuclear-powered ship

    International Nuclear Information System (INIS)

    Takamasa, Tomoji; Miyashita, Kunio

    2000-01-01

    establishment of laws and standards related to the operation of a nuclear-powered ship, were discussed. The group evaluated shipping costs for nuclear-powered container ships using the MRX (Marine Reactor X, as currently designed by JAERI), sailing the North Pacific route. The cost report focused on whether large, high-speed container ships with the MRX, carrying a varying number of containers (4000, 6000, and 8000 TEU) and sailing at varying ship speeds (25, 30, and 34 knots) could compete economically with diesel ships. Comparing transportation costs for diesel container ships and nuclear-powered ships operated on the Pacific Ocean, we found that the latter had an advantage over the former when ship speed was over 30 knots. (author)

  6. Desertions in nineteenth-century shipping: modelling quit behaviour

    OpenAIRE

    Jari Ojala; Jaakko Pehkonen; Jari Eloranta

    2013-01-01

    Ship jumping in foreign ports was widespread throughout the age of sail. Desertion by seamen was illegal, it occurred abroad, and men who deserted only seldom returned home. We analyse desertion quantitatively and link it to the broader question of quit behaviour and labour turnover. Though the better wages paid at the foreign ports were the main reason for desertion, the regression model of the determinants of desertion indicates that outside opportunities, such as migration, and monetary in...

  7. Investigations on sail force by full scale measurement and numerical calculation. Part 1. Steady sailing performance; Sail ryutairyoku ni kansuru jissen shiken to suchi keisan. 1. Teijo hanso seino

    Energy Technology Data Exchange (ETDEWEB)

    Masuyama, Y.; Fukasawa, T. [Kanazawa Institute of Technology, Ishikawa (Japan); Kitazaki, T. [DMW Corp., Tokyo (Japan)

    1997-06-01

    Sailing forces are measured with a 10.3m long full-scale sailing boat, equipped with a sail force dynamometer, CCD camera for sail shape measurement and an instrument for detecting sailing conditions of the hull, in order to obtain highly reliable performance data of a sailing yacht. The vortex lattice method is used for step-by-step numerical calculations, and the results are compared with the observed ones. The test results clearly show performance changing with slight changes in relative wind directions and sail shapes, which are not clearly obtained by the traditional wind tunnel tests. The calculated results, although deviating from the observed ones to some extent, well represent trends of performance changing with wind directions and sail shapes. In particular, changed performance caused by slight changes in draft at the main sail is clearly demonstrated. The numerical calculation is considered to be useful for searching for sail trim conditions. 17 refs., 18 figs., 1 tab.

  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. Modeling Liner Shipping Service Selection and Container Flows using a Multi-layer Network

    DEFF Research Database (Denmark)

    Karsten, Christian Vad; Balakrishnan, Anant

    We introduce a new formulation for the tactical planning problem facing container shipping companies of selecting the best subset of sailing routes from a given pool of candidate routes so as to maximize profit. Since most containers are sent directly or transshipped at most twice in current liner...

  10. Dynamics and Control of a Flexible Solar Sail

    OpenAIRE

    Jiafu Liu; Siyuan Rong; Fan Shen; Naigang Cui

    2014-01-01

    Solar sail can merely make use of solar radiation pressure (SRP) force as the thrust for space missions. The attitude dynamics is obtained for the highly flexible solar sail with control vanes, sliding masses, and a gimbaled control boom. The vibration equations are derived considering the geometric nonlinearity of the sail structure subjected to the forces generated by the control vanes, solar radiation pressure (SRP), and sliding masses. Then the dynamic models for attitude/vibration contr...

  11. [A paraplegic skipper of his own sailing yacht].

    Science.gov (United States)

    Christians, U

    1985-05-01

    Drawing on personal experience, the author points out that paraplegics too are capable of independent sailing. Physical restrictions relative to on-board mobility, sail manoeuvring and change of sides can be made up for by structural adaptions and special techniques. Certain safety precautions are indispensable. The sailing performance of paraplegics compares with that of ablebodied sailors, and cruising under a paraplegic skipper's responsibility is certainly possible.

  12. Numerical Analysis of Magnetic Sail Spacecraft

    International Nuclear Information System (INIS)

    Sasaki, Daisuke; Yamakawa, Hiroshi; Usui, Hideyuki; Funaki, Ikkoh; Kojima, Hirotsugu

    2008-01-01

    To capture the kinetic energy of the solar wind by creating a large magnetosphere around the spacecraft, magneto-plasma sail injects a plasma jet into a strong magnetic field produced by an electromagnet onboard the spacecraft. The aim of this paper is to investigate the effect of the IMF (interplanetary magnetic field) on the magnetosphere of magneto-plasma sail. First, using an axi-symmetric two-dimensional MHD code, we numerically confirm the magnetic field inflation, and the formation of a magnetosphere by the interaction between the solar wind and the magnetic field. The expansion of an artificial magnetosphere by the plasma injection is then simulated, and we show that the magnetosphere is formed by the interaction between the solar wind and the magnetic field expanded by the plasma jet from the spacecraft. This simulation indicates the size of the artificial magnetosphere becomes smaller when applying the IMF.

  13. Fast ship

    OpenAIRE

    Keuning, J.A.

    2014-01-01

    The invention concerns a ship whereby the hull and the mechanical propulsion device are designed such that the Froude number is larger than 0.5. In the aft ship the hull has a bottom with V-shaped bottom surfaces with a deadrise angle that is less than 40 degrees and the hull has substantially vertical sides. In the hull are a passenger compartment and a trim tank. The trim tank volume is such that the weight of a filled trim tank is more than 30 % of the weight of displacement of the hull wi...

  14. 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

  15. Spontaneous neonatal pneumomediastinum: the "spinnaker sail" sign.

    Science.gov (United States)

    Lawal, T A; Glüer, S; Reismann, M; Dördelmann, M; Schirg, E; Ure, B

    2009-02-01

    Spontaneous pneumomediastinum is a rare condition in the newborn, not associated with identifiable trauma or mechanical ventilation. It is diagnosed by a combination of physical examination and confirmatory chest radiograph, with various recognized signs identifiable in this condition. We report the case of a male neonate, who had pneumomediastinum confirmed by the presence of a wind blown spinnaker sail sign and was managed conservatively. We also reviewed the literature.

  16. A first course in optimum design of yacht sails

    Science.gov (United States)

    Sugimoto, Takeshi

    1993-03-01

    The optimum sail geometry is analytically obtained for the case of maximizing the thrust under equality and inequality constraints on the lift and the heeling moment. A single mainsail is assumed to be set close-hauled in uniform wind and upright on the flat sea surface. The governing parameters are the mast height and the gap between the sail foot and the sea surface. The lifting line theory is applied to analyze the aerodynamic forces acting on a sail. The design method consists of the variational principle and a feasibility study. Almost triangular sails are found to be optimum. Their advantages are discussed.

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

    Energy Technology Data Exchange (ETDEWEB)

    Manchester, Zachary [John A. Paulson School of Engineering and Applied Science, Harvard University, 60 Oxford St., Cambridge, MA 02138 (United States); Loeb, Abraham, E-mail: zmanchester@seas.harvard.edu [Astronomy Department, Harvard University, 60 Garden St., Cambridge, MA 02138 (United States)

    2017-03-10

    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 simulations are performed to verify our analytical results.

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

    International Nuclear Information System (INIS)

    Manchester, Zachary; Loeb, Abraham

    2017-01-01

    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 simulations are performed to verify our analytical results.

  19. 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.

  20. Adult sail sign: radiographic and computed tomographic features.

    Science.gov (United States)

    Lee, Yu-Jin; Han, Daehee; Koh, Young Hwan; Zo, Joo Hee; Kim, Sang-Hyun; Kim, Deog Kyeom; Lee, Jeong Sang; Moon, Hyeon Jong; Kim, Jong Seung; Chun, Eun Ju; Youn, Byung Jae; Lee, Chang Hyun; Kim, Sam Soo

    2008-02-01

    The sail sign is a well-known radiographic feature of the pediatric chest. This sign can be observed in an adult population as well, but for a different reason. To investigate the sail sign appearing in adult chest radiography. Based on two anecdotal adult cases in which frontal chest radiographs showed the sail sign, we prospectively screened radiographs of 10,238 patients to determine the incidence of the sail sign found in adults in their 40s or older. The cause of the sail sign was assessed using computed tomography (CT). The sail sign was revealed in 10 (seven males, three females; median age 60.6 years) of 10,238 patients. Of these 10 patients with a sail sign on frontal radiographs, eight underwent CT. The frontal radiographs of these 10 patients showed a concave superior margin toward the lung in nine patients, a concave inferior margin in five, and a double-lined inferior margin in three. Lateral radiographs disclosed a focal opacity over the minor fissure in five of six patients, which was either fuzzy (n = 4) or sharp (n = 1) in its upper margin, and was sometimes double lined in the inferior margin (n = 3). CT revealed the anterior mediastinal fat to be the cause of the radiographic sail sign, which stretched laterally from the mediastinum to insinuate into the minor fissure. The incidence of sail sign on adult chest radiographs is about 0.1%. The sign is specific enough to eliminate the need for more sophisticated imaging.

  1. Fast Radio Bursts from Extragalactic Light Sails

    Energy Technology Data Exchange (ETDEWEB)

    Lingam, Manasvi [John A. Paulson School of Engineering and Applied Sciences, Harvard University, 29 Oxford Street, Cambridge, MA 02138 (United States); Loeb, Abraham, E-mail: manasvi@seas.harvard.edu [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

    2017-03-10

    We examine the possibility that fast radio bursts (FRBs) originate from the activity of extragalactic civilizations. Our analysis shows that beams used for powering large light sails could yield parameters that are consistent with FRBs. The characteristic diameter of the beam emitter is estimated through a combination of energetic and engineering constraints, and both approaches intriguingly yield a similar result that is on the scale of a large rocky planet. Moreover, the optimal frequency for powering the light sail is shown to be similar to the detected FRB frequencies. These “coincidences” lend some credence to the possibility that FRBs might be artificial in origin. Other relevant quantities, such as the characteristic mass of the light sail, and the angular velocity of the beam, are also derived. By using the FRB occurrence rate, we infer upper bounds on the rate of FRBs from extragalactic civilizations in a typical galaxy. The possibility of detecting fainter signals is briefly discussed, and the wait time for an exceptionally bright FRB event in the Milky Way is estimated.

  2. Fast Radio Bursts from Extragalactic Light Sails

    International Nuclear Information System (INIS)

    Lingam, Manasvi; Loeb, Abraham

    2017-01-01

    We examine the possibility that fast radio bursts (FRBs) originate from the activity of extragalactic civilizations. Our analysis shows that beams used for powering large light sails could yield parameters that are consistent with FRBs. The characteristic diameter of the beam emitter is estimated through a combination of energetic and engineering constraints, and both approaches intriguingly yield a similar result that is on the scale of a large rocky planet. Moreover, the optimal frequency for powering the light sail is shown to be similar to the detected FRB frequencies. These “coincidences” lend some credence to the possibility that FRBs might be artificial in origin. Other relevant quantities, such as the characteristic mass of the light sail, and the angular velocity of the beam, are also derived. By using the FRB occurrence rate, we infer upper bounds on the rate of FRBs from extragalactic civilizations in a typical galaxy. The possibility of detecting fainter signals is briefly discussed, and the wait time for an exceptionally bright FRB event in the Milky Way is estimated.

  3. Ship's barbers

    OpenAIRE

    Unknown

    2003-01-01

    Showing two sailors having their hair cut (? one is possibly being shaved) on board ship. Three other sailors can be seen standing on the right-hand side of the photograph. The photograph is from an album inscribed 'H.M.S. Lancaster; Mediterranean Photographic Album: Diary of Events and Important Places Visited during the Commission 1910-1912' on the cover. This album was the property of Sydney Harold Liddle.

  4. 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...

  5. 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...

  6. School-Based Adolescent Groups: The Sail Model.

    Science.gov (United States)

    Thompson, John L.; And Others

    The manual outlines the processes, policies, and actual program implementation of one component of a Minnesota program for emotionally disturbed adolescents (Project SAIL): the development of school-based therapy/intervention groups. The characteristics of SAIL students are described, and some considerations involved in providing group services…

  7. 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.

  8. 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

  9. 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.

  10. Asteroid body-fixed hovering using nonideal solar sails

    International Nuclear Information System (INIS)

    Zeng, Xiang-Yuan; Jiang, Fang-Hua; Li, Jun-Feng

    2015-01-01

    The problem of body-fixed hovering over an asteroid using a compact form of nonideal solar sails with a controllable area is investigated. Nonlinear dynamic equations describing the hovering problem are constructed for a spherically symmetric asteroid. Numerical solutions of the feasible region for body-fixed hovering are obtained. Different sail models, including the cases of ideal, optical, parametric and solar photon thrust, on the feasible region is studied through numerical simulations. The influence of the asteroid spinning rate and the sail area-to-mass ratio on the feasible region is discussed. The required orientations for the sail and their corresponding variable lightness numbers are given for different hovering radii to identify the feasible region of the body-fixed hovering. An attractive scenario for a mission is introduced to take advantage of solar sail hovering. (paper)

  11. Analysis of ship maneuvering data from simulators

    Science.gov (United States)

    Frette, V.; Kleppe, G.; Christensen, K.

    2011-03-01

    We analyze complex manuevering histories of ships obtained from training sessions on bridge simulators. Advanced ships are used in fields like offshore oil exploration: dive support vessels, supply vessels, anchor handling vessels, tugs, cable layers, and multi-purpose vessels. Due to high demands from the operations carried out, these ships need to have very high maneuverability. This is achieved through a propulsion system with several thrusters, water jets, and rudders in addition to standard propellers. For some operations, like subsea maintenance, it is crucial that the ship accurately keeps a fixed position. Therefore, bridge systems usually incorporate equipment for Dynamic Positioning (DP). DP is a method to keep ships and semi submersible rigs in a fixed position using the propulsion systems instead of anchors. It may also be used for sailing a vessel from one position to another along a predefined route. Like an autopilot on an airplane, DP may operate without human involvement. The method relies on accurate determination of position from external reference systems like GPS, as well as a continuously adjusted mathematical model of the ship and external forces from wind, waves and currents. In a specific simulator exercise for offshore crews, a ship is to be taken up to an installation consisting of three nearby oil platforms connected by bridges (Frigg field, North Sea), where a subsea inspection is to be carried out. Due to the many degrees of freedom during maneuvering, including partly or full use of DP, the chosen routes vary significantly. In this poster we report preliminary results on representations of the complex maneuvering histories; representations that allow comparison between crew groups, and, possibly, sorting of the different strategic choices behind.

  12. Moving an asteroid with electric solar wind sail

    Science.gov (United States)

    Merikallio, S.; Janhunen, P.

    2010-12-01

    The electric solar wind sail (E-Sail) is a new propulsion method for interplanetary travel which was invented in 2006 and is currently under development. The E-Sail uses charged tethers to extract momentum from the solar wind particles to obtain propulsive thrust. According to current estimates, the E-Sail is 2-3 orders of magnitude better than traditional propulsion methods (chemical rockets and ion engines) in terms of produced lifetime-integrated impulse per propulsion system mass. Here we analyze the problem of using the E-Sail for directly deflecting an Earth-threatening asteroid. The problem then culminates into how to attach the E-Sail device to the asteroid. We assess alternative attachment strategies, namely straightforward direct towing with a cable and the gravity tractor method which works for a wider variety of situations. We also consider possible techniques to scale up the E-Sail force beyond the baseline one Newton level to deal with more imminent or larger asteroid or cometary threats. As a baseline case we consider an asteroid of effective diameter of 140 m and mass of 3 million tons, which can be deflected with a baseline 1 N E-Sail within 10 years. With a 5 N E-Sail the deflection could be achieved in 5 years. Once developed, the E-Sail would appear to provide a safe and reasonably low-cost way of deflecting dangerous asteroids and other heavenly bodies in cases where the collision threat becomes known several years in advance.

  13. Risk Analysis on Ship Wreck and Container Cargo to Ship Navigation

    Directory of Open Access Journals (Sweden)

    Muhammad Badrus Zaman

    2017-03-01

    Full Text Available Wreck of a ship is an incident that must be avoided. Ship accidents are generally caused by a several cases, such as human error, natural disaster, technical errors, missed communication, poor condition of the ship, and many more. Ship wreckage have huge impact for ship navigation, environment, economics, and others. Those impact have many disadvantages for the shipowners, and also for environment. For examples the fuel spills that pollute the environment, make disturbance to sailing ship because the track for those navigation is blocked by the ship wreck and their cargo especially on shallow location (<50 m. These research will discuss the effect the container when it is floats on the sea and its interference other ships. The main objective of this study is to present a risk assessment on the environmental impact of the wreck and container cargo. Wrecks on the seabed is likely to pose a risk to passing ships. container and its contents as well as the possibility of refloat, and also their environmental risks emanating from the wreck and container cargo, such as fuels, lubricants, and chemical cargo. Variations scenario is a collision between ships that pass by floating containers. The frequency of refloating container, and the consequences of the passing ship depends on several factors, which will be the subject of research. However, because of the frequency of refloating containers is unlikely, then the risk is low and does not pose a danger to navigation. These risk assessment using risk matrix 5x5 which is the combined value of the frequency and consequences of the incident. The results of this study indicate the level of risk, whether the risk is accepted, not accepted or received by considering the costs and benefits (ALARP. To consequence, there are two parameters which energy is absorbed and the penetration occurs. The absorbed energy is divided into two, namely the energy absorbed by ship and the energy absorbed by containers. In this

  14. Orbital Dynamics of an Oscillating Sail in the Earth-Moon System

    NARCIS (Netherlands)

    Heiligers, M.J.; Ceriotti, M.

    2017-01-01

    The oscillating sail is a novel solar sail configuration where a triangular sail is released at a deflected angle with respect to the Sun-direction. As a result, the sail will conduct an undamped oscillating motion around the Sun-line due to the offset between the centre-of-pressure and

  15. 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...

  16. ‘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...

  17. A study for bank effect on ship traffic in narrow water channels using cellular automata

    Science.gov (United States)

    Sun, Zhuo; Cong, Shuang; Pan, Junnan; Zheng, Jianfeng

    2017-12-01

    In narrow water channels, bank might affect nearby ships due to hydrodynamic forces (bank effect). To avoid accidents, different sailing rules (i.e., lane-changing, speed control) are required. In this paper, a two-lane cellular automata model is proposed to evaluate such phenomena. Numerical experiments show that ships will form a “slow-moving chunk” in the bank area, which will significantly block the flux. As further study demonstrated to alleviate bank effect, ship speed and bank length should be controlled.

  18. 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

  19. 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).

  20. The solar sail: Current state of the problem

    Science.gov (United States)

    Polyakhova, Elena; Korolev, Vladimir

    2018-05-01

    Mathematical models of dynamics of the spacecraft with a solar sail to control orbital motion and rotation of the entire structureare considered. The movement of a spacecraftby a solar sail is based on the effect of light pressure. The magnitude and direction of the light pressure force vector is determined by the size and properties of the sail surface and the orientation angle relative to the sunlight flux. It is possible to vary the properties, sizes or locations of the sails to control the motion. Turning the elements of the sail, we get the opportunity to control the direction of the vector of the acting force and the moment with respect to the center of mass. Specificity of solar sail control is the interaction of orbital motion and rotational movements of the entire structure, which could provide the desired orientation and stability at small perturbations. The solar sail can be used for flights to the major planets, to meet with asteroids and comet, to realize a special desired motion in the neighborhood of the Sun or near the Earth.

  1. 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.

  2. Phobos/Deimos sample return via solar sail.

    Science.gov (United States)

    Matloff, Gregory L; Taylor, Travis; Powell, Conley; Moton, Tryshanda

    2005-12-01

    A sample-return mission to the Martian satellites using a con-temporary solar sail for all post-Earth-escape propulsion is proposed. The 0.015 kg/m(2) areal mass-thickness sail unfurls after launch and injection onto a Mars-bound Hohmann-transfer ellipse. Structure and payload increase spacecraft areal mass thickness to 0.028 kg/m(2). During the Mars encounter, the sail functions as a parachute in the outer atmosphere of Mars to accomplish aerocapture. On-board thrusters or the sail maneuver the spacecraft into an orbit with periapsis near Mars and apoapsis near Phobos. The orbit is circularized for Phobos-rendezvous; surface samples are collected. The sail then raises the orbit for Deimos-rendezvous and sample collection. The sail next places the spacecraft on an Earth-bound Hohmann-transfer ellipse. During Earth encounter, the sail accomplishes Earth-aerocapture or partially decelerates the sample container for entry into the Earth's atmosphere. Mission mass budget is about 218 grams and mission duration is less than five years.

  3. NanoSail - D Orbital and Attitude Dynamics

    Science.gov (United States)

    Heaton, Andrew F.; Faller, Brent F.; Katan, Chelsea K.

    2013-01-01

    NanoSail-D unfurled January 20th, 2011 and successfully demonstrated the deployment and deorbit capability of a solar sail in low Earth orbit. The orbit was strongly perturbed by solar radiation pressure, aerodynamic drag, and oblate gravity which were modeled using STK HPOP. A comparison of the ballistic coefficient history to the orbit parameters exhibits a strong relationship between orbital lighting, the decay rate of the mean semi-major axis and mean eccentricity. A similar comparison of mean solar area using the STK HPOP solar radiation pressure model exhibits a strong correlation of solar radiation pressure to mean eccentricity and mean argument of perigee. NanoSail-D was not actively controlled and had no capability on-board for attitude or orbit determination. To estimate attitude dynamics we created a 3-DOF attitude dynamics simulation that incorporated highly realistic estimates of perturbing forces into NanoSail-D torque models. By comparing the results of this simulation to the orbital behavior and ground observations of NanoSail-D, we conclude that there is a coupling between the orbit and attitude dynamics as well as establish approximate limits on the location of the NanoSail-D solar center of pressure. Both of these observations contribute valuable data for future solar sail designs and missions.

  4. A Base Integer Programming Model and Benchmark Suite for Liner-Shipping Network Design

    DEFF Research Database (Denmark)

    Brouer, Berit Dangaard; Alvarez, Fernando; Plum, Christian Edinger Munk

    2014-01-01

    . The potential for making cost-effective and energy-efficient liner-shipping networks using operations research (OR) is huge and neglected. The implementation of logistic planning tools based upon OR has enhanced performance of airlines, railways, and general transportation companies, but within the field......The liner-shipping network design problem is to create a set of nonsimple cyclic sailing routes for a designated fleet of container vessels that jointly transports multiple commodities. The objective is to maximize the revenue of cargo transport while minimizing the costs of operation...... sources of liner shipping for OR researchers in general. We describe and analyze the liner-shipping domain applied to network design and present a rich integer programming model based on services that constitute the fixed schedule of a liner shipping company. We prove the liner-shipping network design...

  5. Adult Sail Sign: Radiographic and Computed Tomographic Features

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yu-Jin; Han, Daehee; Koh, Young Hwan; Zo, Joo Hee; Kim, Sang-Hyun; Kim, Deog Kyeom; Lee, Jeong Sang; Moon, Hyeon Jong; Kim, Jong Seung; Chun, Eun Ju; Youn, Byung Jae; Lee, Chang Hyun; Kim, Sam Soo (Dept. of Radiology, Cheil General Hospital, Kwandong Univ. College of Medicine, Seoul (KR))

    2008-02-15

    Background: The sail sign is a well-known radiographic feature of the pediatric chest. This sign can be observed in an adult population as well, but for a different reason. Purpose: To investigate the sail sign appearing in adult chest radiography. Material and Methods: Based on two anecdotal adult cases in which frontal chest radiographs showed the sail sign, we prospectively screened radiographs of 10,238 patients to determine the incidence of the sail sign found in adults in their 40s or older. The cause of the sail sign was assessed using computed tomography (CT). Results: The sail sign was revealed in 10 (seven males, three females; median age 60.6 years) of 10,238 patients. Of these 10 patients with a sail sign on frontal radiographs, eight underwent CT. The frontal radiographs of these 10 patients showed a concave superior margin toward the lung in nine patients, a concave inferior margin in five, and a double-lined inferior margin in three. Lateral radiographs disclosed a focal opacity over the minor fissure in five of six patients, which was either fuzzy (n = 4) or sharp (n = 1) in its upper margin, and was sometimes double lined in the inferior margin (n = 3). CT revealed the anterior mediastinal fat to be the cause of the radiographic sail sign, which stretched laterally from the mediastinum to insinuate into the minor fissure. Conclusion: The incidence of sail sign on adult chest radiographs is about 0.1%. The sign is specific enough to eliminate the need for more sophisticated imaging

  6. Adult Sail Sign: Radiographic and Computed Tomographic Features

    International Nuclear Information System (INIS)

    Lee, Yu-Jin; Han, Daehee; Koh, Young Hwan; Zo, Joo Hee; Kim, Sang-Hyun; Kim, Deog Kyeom; Lee, Jeong Sang; Moon, Hyeon Jong; Kim, Jong Seung; Chun, Eun Ju; Y oun, Byung Jae; Lee, Chang Hyun; Kim, Sam Soo

    2008-01-01

    Background: The sail sign is a well-known radiographic feature of the pediatric chest. This sign can be observed in an adult population as well, but for a different reason. Purpose: To investigate the sail sign appearing in adult chest radiography. Material and Methods: Based on two anecdotal adult cases in which frontal chest radiographs showed the sail sign, we prospectively screened radiographs of 10,238 patients to determine the incidence of the sail sign found in adults in their 40s or older. The cause of the sail sign was assessed using computed tomography (CT). Results: The sail sign was revealed in 10 (seven males, three females; median age 60.6 years) of 10,238 patients. Of these 10 patients with a sail sign on frontal radiographs, eight underwent CT. The frontal radiographs of these 10 patients showed a concave superior margin toward the lung in nine patients, a concave inferior margin in five, and a double-lined inferior margin in three. Lateral radiographs disclosed a focal opacity over the minor fissure in five of six patients, which was either fuzzy (n = 4) or sharp (n = 1) in its upper margin, and was sometimes double lined in the inferior margin (n = 3). CT revealed the anterior mediastinal fat to be the cause of the radiographic sail sign, which stretched laterally from the mediastinum to insinuate into the minor fissure. Conclusion: The incidence of sail sign on adult chest radiographs is about 0.1%. The sign is specific enough to eliminate the need for more sophisticated imaging

  7. A basic tool for computer-aided sail design

    International Nuclear Information System (INIS)

    Thrasher, D.F.; Dunyak, T.J.; Mook, D.T.; Nayfeh, A.H.

    1985-01-01

    Recent developments in modelling lifting surfaces have provided a tool that also can be used to model sails. The simplest of the adequate models is the vortex-lattice method. This method can fully account for the aerodynamic interactions among several lifting surfaces having arbitrary platforms, camber, and twist as long as separation occurs only along the edges and the phenomenon known as vortex bursting does not occur near the sails. This paper describes this method and how it can be applied to the design of sails

  8. Development of software for handling ship's pharmacy.

    Science.gov (United States)

    Nittari, Giulio; Peretti, Alessandro; Sibilio, Fabio; Ioannidis, Nicholas; Amenta, Francesco

    2016-01-01

    Ships are required to carry a given amount of medicinal products and medications depending on the flag and the type of vessel. These medicines are stored in the so called ship's "medicine chest" or more properly - a ship pharmacy. Owing to the progress of medical sciences and to the increase in the mean age of seafarers employed on board ships, the number of pharmaceutical products and medical devices required by regulations to be carried on board ships is increasing. This may make handling of the ship's medicine chest a problem primarily on large ships sailing on intercontinental routes due to the difficulty in identifying the correspondence between medicines obtained abroad with those available at the national market. To minimise these problems a tool named Pharmacy Ship (acronym: PARSI) has been developed. The application PARSI is based on a database containing the information about medicines and medical devices required by different countries regulations. In the first application the system was standardised to comply with the Italian regulations issued on the 1st October, 2015 which entered into force on the 18 January 2016. Thanks to PARSI it was possible to standardize the inventory procedures, facilitate the work of maritime health authorities and make it easier for the crew, not professional in the field, to handle the 'medicine chest' correctly by automating the procedures for medicines management. As far as we know there are no other similar tools available at the moment. The application of the software, as well as the automation of different activities, currently carried out manually, will help manage (qualitatively and quantitatively) the ship's pharmacy. The system developed in this study has proved to be an effective tool which serves to guarantee the compliance of the ship pharmacy with regulations of the flag state in terms of medicinal products and medications. Sharing the system with the Telemedical Maritime Assistance Service may result in

  9. Ship cabin leakage alarm based on ARM SCM

    Science.gov (United States)

    Qu, Liyan

    2018-03-01

    If there is a leakage in the cabin of a sailing ship, it is a major accident that threatens the personnel and property of the ship. If we can’t take timely measures, there will be a devastating disaster. In order to judge the leakage of the cabin, it is necessary to set up a leakage alarm system, so as to achieve the purpose of detecting and alarming the leakage of the cabin, and avoid the occurrence of accidents. This paper discusses the design of ship cabin leakage alarm system based on ARM SCM. In order to ensure the stability and precision of the product, the hardware design of the alarm system is carried out, such as circuit design, software design, the programming of SCM, the software programming of upper computer, etc. It is hoped that it can be of reference value to interested readers.

  10. Fiscal 1978 annual report of Japan Nuclear Ship Development Agency

    International Nuclear Information System (INIS)

    1979-01-01

    In October, 1978, the nuclear ship Mutsu was moved to Sasebo Port from Ominato Port for shield repair and comprehensive safety check-up and repair; and this was a long-standing problem for the ship. In face of a new energy age, Japan Nuclear Ship Development Agency is endeavoring to bring up the nuclear ship technology in Japan to the top level in the world by successfully completing the n.s. Mutsu through perfect safety and reliability. For Japan, which is a leading country of shipbuilding and merchant shipping, the development of nuclear ships is extremely important. On the activities of the agency from April, 1978, to March, 1979, the following matters are described: safety check and shielding repair of the n.s. Mutsu; Maintenance of the n.s. Mutsu at Ominato and Sasebo ports and its sailing to Sasebo port; works at Sasebo port before and after the arrival of the n.s. Mutsu; maintenance works of the Mutsu facilities at Ominato port; governmental formalities for permission and approval; training of ship crew; administrative works. (J.P.N.)

  11. Friction stir welding sets sail in China

    International Nuclear Information System (INIS)

    Luan, Guohong

    2007-01-01

    Today, Friction Stir Welding has set sail in China. As the pioneer of FSW development in the China territory, China FSW Centre hes made outstanding achievements in FSW technique development, FSW engineering, FSW equipment and FSW product. But the real industrial applications of FSW in China are just begining. With the planned national long-term development programmes and huge market requirement in aerospace, aviation, shipbuilding, railway, power and energy industries, FSW will continue to develop rapidly in the next 10 years. FSW will continue to develop rapidly in the next 10 years. FSW not only raises the level of joining techniques in Chinese industrial companies, but also increase the competitive ability of the industrial products made in china

  12. 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.

  13. Periodic orbits of solar sail equipped with reflectance control device in Earth-Moon system

    Science.gov (United States)

    Yuan, Jianping; Gao, Chen; Zhang, Junhua

    2018-02-01

    In this paper, families of Lyapunov and halo orbits are presented with a solar sail equipped with a reflectance control device in the Earth-Moon system. System dynamical model is established considering solar sail acceleration, and four solar sail steering laws and two initial Sun-sail configurations are introduced. The initial natural periodic orbits with suitable periods are firstly identified. Subsequently, families of solar sail Lyapunov and halo orbits around the L1 and L2 points are designed with fixed solar sail characteristic acceleration and varying reflectivity rate and pitching angle by the combination of the modified differential correction method and continuation approach. The linear stabilities of solar sail periodic orbits are investigated, and a nonlinear sliding model controller is designed for station keeping. In addition, orbit transfer between the same family of solar sail orbits is investigated preliminarily to showcase reflectance control device solar sail maneuver capability.

  14. Findings from NASA's 2015-2017 Electric Sail Investigations

    Science.gov (United States)

    Wiegmann, Bruce. M.

    2017-01-01

    Electric Sail (E-Sail) propulsion systems will enable scientific spacecraft to obtain velocities of up to 10 astronomical units per year without expending any on-board propellant. The E-Sail propulsion is created from the interaction of a spacecraft's positively charged multi-kilometer-length conductor/s with protons that are present in the naturally occurring hypersonic solar wind. The protons are deflected via natural electrostatic repulsion forces from the Debye sheath that is formed around a charged wire in space, and this deflection of protons creates thrust or propulsion in the opposite direction. It is envisioned that this E-Sail propulsion system can provide propulsion throughout the solar system and to the heliosphere and beyond. Consistent with the concept of a "sail," no propellant is needed as electrostatic repulsion interactions between the naturally occurring solar wind protons and a positively charged wire creates the propulsion. The basic principle on which the Electric Sail operates is the exchange of momentum between an "electric sail" and solar wind, which continually flows radially away from the sun at speeds ranging from 300 to 700 kilometers per second. The "sail" consists of an array of long, charged wires which extend radially outward 10 to 30 kilometers from a slowly rotating spacecraft. Momentum is transferred from the solar wind to the array through the deflection of the positively charged solar wind protons by a high voltage potential applied to the wires. The thrust generated by an E-Sail is proportional to the area of the sail, which is given by the product of the total length of the wires and the effective wire diameter. The wire is approximately 0.1 millimeters in diameter. However, the effective diameter is determined by the distance the applied electric potential penetrates into space around the wire (on the order of 10 meters at 1 astronomical unit). As a result, the effective area over which protons are repelled is proportional

  15. SETI via Leakage from Light Sails in Exoplanetary Systems

    OpenAIRE

    Guillochon, James F.; Loeb, Abraham

    2015-01-01

    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 ...

  16. Flowing Plasma Interaction with an Electric Sail Tether Element

    Science.gov (United States)

    Schneider, Todd; Vaughn, Jason; Wright, Kenneth; Anderson, Allen; Stone, Nobie

    2017-01-01

    Harnessing the power of the solar wind, an Electric Sail, or E-sail, is a relatively new concept that promises to deliver high speed propellant-less propulsion. The electric sail is an invention made in 2006 at the Kumpula Space Centre in Finland by Pekka Janhunen [Janhunen and Sandroos, 2007]. At its core, an electric sail utilizes multiple positively biased tethers which exchange momentum with solar wind protons via the repelling electric field established around each tether, in other words, by reflecting the solar wind protons. Recognizing the solar wind is a plasma, the effective repelling area of each tether is increased significantly by the formation a plasma sheath around each tether. Fig. 1 shows schematically a spacecraft employing an electric sail. The positive voltage bias (greater than10kV) applied to each tether naturally results in electron collection. Therefore, the electric sail concept necessarily includes an electron source (electron gun) to return collected electrons to space and maintain the positive bias of the tether system.

  17. 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.

  18. The KiteShip (TM) project

    Energy Technology Data Exchange (ETDEWEB)

    De winter, Francis; Swenson, Ronald B; Culp, David [Santa Cruz, CA (United States)

    2000-07-01

    Foreseeable crude oil shortages provide an incentive to use wind power in the merchant marine again, to save fuel by providing propulsion power. Out prototype KiteShip (TM), a lightweight fiberglass proa 7 m long, has been sailed with 2 different sizes of kites in fresh water. The kites are shaped like parafoil wings, with areas of 4 sq m and 9 sq m. Steering is accomplished with two coupled rudders, one fore and one aft. We have been encouraged by the boat speed and the handling, although we have encountered only light winds up to now, of no more than about 20 km/ht. In the next phase we will employ a custom-built kite of 2 sq m. and will also start sailing in the ocean with heavier winds, of 40 km/hr and above. [Spanish] La escasez previsible de petroleo motiva volver a utilizar la fuerza del viento en la marina mercante, para ahorrar combustible al suministrar la potencia de propulsion. Nuestro prototipo KiteShip (MR), con una proa ligera de fibra de vidrio con 7 m de longitud, ha navegado con dos diferentes tipos de vela ({sup k}ite{sup )} en agua dulce. Los kites tienen forma de alas de parafol, con areas de 4 m{sup 2} y 9 m{sup 2}. La direccion se logra con dos timones acoplados, uno en la proa y otro en la popa. Nos entusiasmo la velocidad del bote y su manejo, aunque hemos encontrado hasta ahora solo vientos ligeros de no mas de alrededor de 20 km/hr. En la siguiente fase emplearemos un kite hecho a la medida, de 28 m{sup 2} y tambien comenzaremos a navegar en el oceano con vientos mas fuertes de 40 km/hr o mas.

  19. Green Shipping Practices of Shipping Firms

    Directory of Open Access Journals (Sweden)

    Young-Tae Chang

    2017-05-01

    Full Text Available The primary objective of this study is to provide an empirical research using structural equation modeling to identify the factors that motivate shipping firms to adopt green shipping practices (GSP. Furthermore, it also examines if adopting GSP can enhance the shipping firms’ environmental and productivity performance. The findings show that shipping firms are motivated to adopt GSP mostly by industrial norms set by institutionalized associations. They are also motivated by customers’ demand for environmental friendliness and their own strategy to make good image. Unlike our expectation, government regulations and international environmental laws are not significant in influencing shipping firms to adopt GSP. Moreover, adoption of green shipping practices can improve the environmental and productivity performance of the shipping firms.

  20. Green shipping management

    CERN Document Server

    Lun, Y H Venus; Wong, Christina W Y; Cheng, T C E

    2016-01-01

    This book presents theory-driven discussion on the link between implementing green shipping practices (GSP) and shipping firm performance. It examines the shipping industry’s challenge of supporting economic growth while enhancing environmental performance. Consisting of nine chapters, the book covers topics such as the conceptualization of green shipping practices (GSPs), measurement scales for evaluating GSP implementation, greening capability, greening and performance relativity (GPR), green management practice, green shipping network, greening capacity, and greening propensity. In view of the increasing quest for environment protection in the shipping sector, this book provides a good reference for firms to understand and evaluate their capability in carrying out green operations on their shipping activities.

  1. Advanced Materials and Production Technology for Very Large Solar Sail Structures, Phase I

    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. The cardiovascular work of competitive dinghy sailing.

    Science.gov (United States)

    Felici, F; Rodio, A; Madaffari, A; Ercolani, L; Marchetti, M

    1999-12-01

    Hiking is the special manoeuvre, which the dinghy sailor uses to counterbalance the capsizing effect of the wind on the boat. In the present research the work required of the heart by this exercise was studied in the laboratory using a boat simulator. Seven Laser male sailors selected from those in the first places in the junior national rank participated in this study. Their endurance, at different levels of isometric hiking efforts, was measured. Energy expenditure due to hiking was estimated from measurements of oxygen consumption, carbon dioxide elimination and blood lactate concentration. The cardiac load was evaluated by measuring blood pressure using the conventional method and heart rate measured by electrocardiography. Cardiac output was measured using the CO2 re-breathing method. Left ventricular work was then calculated as cardiac output multiplied by mean arterial pressure. The most relevant result was that, while whole body cost of hiking was relatively low (about 1 IO2 min-1), the power of the heart was very significant: cardiac output almost doubled with respect to that at rest and arterial mean pressure rose from 12.5 kPa (rest) to 18.5 kPa (hiking). Thus, left ventricular power rose from 1.2 Watt to 3.2 Watt, which is a typical cardiovascular response to muscular isometric contraction. These results assume relevance when a person's eligibility for sailing sports is evaluated.

  3. The shipping man adventures in ship finance

    CERN Document Server

    McCleery, Matthew

    2013-01-01

    When restless New York City hedge fund manager Robert Fairchild watches the Baltic Dry Cargo Index plunge 97%, registering an all-time high and a 25-year low within the span of just six months, he decides to buy a ship. Immediately fantasizing about naming a vessel after his wife, carrying a string of worry beads and being able to introduce himself as a "shipowner" at his upcoming college reunion, Fairchild immediately embarks on an odyssey into the most exclusive, glamorous and high stakes business in the world. From pirates off the coast of Somalia and on Wall Street to Greek and Norwegian shipping magnates, the education of Robert Fairchild is an expensive one. In the end, he loses his hedge fund, but he gains a life - as a Shipping Man. Part fast paced financial thriller, part ship finance text book, The Shipping Man is 310 pages of required reading for anyone with an interest in capital formation for shipping.

  4. Invariant Solar Sail Formations in Elliptical Sun-Synchronous Orbits

    Science.gov (United States)

    Parsay, Khashayar

    Current and past missions that study the Earth's geomagnetic tail require multiple spacecraft to fly in formation about a highly eccentric Keplerian reference orbit that has its apogee inside a predefined science region of interest. Because the geomagnetic tail is directed along the Sun-Earth line and therefore rotates annually, inertially fixed Keplerian orbits are only aligned with the geomagnetic tail once per year. This limitation reduces the duration of the science phase to less than a few months annually. Solar sails are capable of creating non-Keplerian, Sun-synchronous orbits that rotate with the geomagnetic tail. A solar sail flying in a Sun-synchronous orbit will have a continuous presence in the geomagnetic tail throughout the entire year, which significantly improves the in situ observations of the magnetosphere. To achieve a Sun-synchronous orbit, a solar sail is required to maintain a Sun-pointing attitude, which leads to the artificial precession of the orbit apse line in a Sun-synchronous manner, leaving the orbit apogee inside the science region of interest throughout entire the year. 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 dissertation 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

  5. Aerodynamic-structural model of offwind yacht sails

    Science.gov (United States)

    Mairs, Christopher M.

    An aerodynamic-structural model of offwind yacht sails was created that is useful in predicting sail forces. Two sails were examined experimentally and computationally at several wind angles to explore a variety of flow regimes. The accuracy of the numerical solutions was measured by comparing to experimental results. The two sails examined were a Code 0 and a reaching asymmetric spinnaker. During experiment, balance, wake, and sail shape data were recorded for both sails in various configurations. Two computational steps were used to evaluate the computational model. First, an aerodynamic flow model that includes viscosity effects was used to examine the experimental flying shapes that were recorded. Second, the aerodynamic model was combined with a nonlinear, structural, finite element analysis (FEA) model. The aerodynamic and structural models were used iteratively to predict final flying shapes of offwind sails, starting with the design shapes. The Code 0 has relatively low camber and is used at small angles of attack. It was examined experimentally and computationally at a single angle of attack in two trim configurations, a baseline and overtrimmed setting. Experimentally, the Code 0 was stable and maintained large flow attachment regions. The digitized flying shapes from experiment were examined in the aerodynamic model. Force area predictions matched experimental results well. When the aerodynamic-structural tool was employed, the predictive capability was slightly worse. The reaching asymmetric spinnaker has higher camber and operates at higher angles of attack than the Code 0. Experimentally and computationally, it was examined at two angles of attack. Like the Code 0, at each wind angle, baseline and overtrimmed settings were examined. Experimentally, sail oscillations and large flow detachment regions were encountered. The computational analysis began by examining the experimental flying shapes in the aerodynamic model. In the baseline setting, the

  6. Design of Sail-Assisted Unmanned Surface Vehicle Intelligent Control System

    OpenAIRE

    Ma, Yong; Zhao, Yujiao; Diao, Jiantao; Gan, Langxiong; Bi, Huaxiong; Zhao, Jingming

    2016-01-01

    To achieve the wind sail-assisted function of the unmanned surface vehicle (USV), this work focuses on the design problems of the sail-assisted USV intelligent control systems (SUICS) and illustrates the implementation process of the SUICS. The SUICS consists of the communication system, the sensor system, the PC platform, and the lower machine platform. To make full use of the wind energy, in the SUICS, we propose the sail angle of attack automatic adjustment (Sail_4A) algorithm and present ...

  7. 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.

  8. 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...... of the study, hMVC was measured dry land in a hiking bench and correlated with the overall results at a national championship. Hiking strap force decreased from the first to the last minute in both 10 min sailing periods (430 ± 131 vs. 285 ± 130 N, P 

  9. 46 CFR 178.325 - Intact stability requirements for a sailing vessel.

    Science.gov (United States)

    2010-10-01

    ... weathertight deck, such as open boats; (4) A vessel that carries more than 49 passengers; (5) A sailing school vessel that carries a combined total of six or more sailing school students or instructors; (6) A vessel... whether the vessel has adequate stability and satisfactory handling characteristics under sail for...

  10. Exploring the Heliogyro’s Superior Orbital Control Capabilities for Solar Sail Halo Orbits

    NARCIS (Netherlands)

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

    2017-01-01

    Solar sailing is an elegant form of space propulsion that reflects solar photons off a large membrane to produce thrust. Different sail configurations exist, including a traditional fixed polygonal flat sail and a heliogyro, which divides the membrane into a number of long, slender blades. The

  11. 76 FR 43893 - Special Local Regulations; Port Huron to Mackinac Island Sail Race

    Science.gov (United States)

    2011-07-22

    ... Local Regulations; Port Huron to Mackinac Island Sail Race AGENCY: Coast Guard, DHS. ACTION: Temporary... Port Huron to Mackinac Island Sail Race. This action is necessary to safely control vessel movements in... Mackinac boat race (officially titled the ``Bell's Beer Bayview Mackinac Race'') will set sail on Saturday...

  12. 75 FR 41373 - Special Local Regulations for Marine Events; Port Huron to Mackinac Island Sail Race

    Science.gov (United States)

    2010-07-16

    ...-AA08 Special Local Regulations for Marine Events; Port Huron to Mackinac Island Sail Race AGENCY: Coast... regulation for the annual Port Huron to Mackinac Island Sail Race. This action is necessary to safely control... the Port Sector Detroit has determined that the start of the Port Huron to Mackinac Island Sail Race...

  13. Nuclear ship engineering simulator

    International Nuclear Information System (INIS)

    Itoh, Yasuyoshi; Kusunoki, Tsuyoshi; Hashidate, Koji

    1991-01-01

    The nuclear ship engineering simulator, which analyzes overall system response of nuclear ship numerically, is now being developed by JAERI as an advanced design tool with the latest computer technology in software and hardware. The development of the nuclear ship engineering simulator aims at grasping characteristics of a reactor plant under the situation generated by the combination of ocean, a ship hull and a reactor. The data from various tests with the nuclear ship 'MUTSU' will be used for this simulator to modulate and verify its functions of reproducing realistic response of nuclear ship, and then the simulator will be utilized for the research and development of advanced marine reactors. (author)

  14. Kiteships, sailing vessels pulled and powered with a kite

    Energy Technology Data Exchange (ETDEWEB)

    Winter, F. de; Swenson, R.B.; Culp, D.

    1999-07-01

    Current windpower technology and future petroleum supply scenarios make it likely that it will become desirable to consider sailing vessels again for the merchant marine. For the wind-powered propulsion it seems possible to use tethered kites, instead of the traditional combination of masts and booms supporting a system of sails. This may be both safer and more cost-effective. The authors are on boat No. 2 in an R and D program aimed at this large scale application, and the present paper represents a progress report. Boat No. 1 was used to achieve speed and power, achieving a speed of 33 knots (over 60 km per hour), and sailing speeds at times of twice the wind velocity. Boat No. 2 will not be used for speed, but for the development of kite deployment and retrieval techniques, with kites of up to 300 sq ft (28 sq m) in surface area.

  15. Solar Array Sails: Possible Space Plasma Environmental Effects

    Science.gov (United States)

    Mackey, Willie R.

    2005-01-01

    An examination of the interactions between proposed "solar sail" propulsion systems with photovoltaic energy generation capabilities and the space plasma environments. Major areas of interactions ere: Acting from high voltage arrays, ram and wake effects, V and B current loops and EMI. Preliminary analysis indicates that arcing will be a major risk factor for voltages greater than 300V. Electron temperature enhancement in the wake will be produce noise that can be transmitted via the wake echo process. In addition, V and B induced potential will generate sheath voltages with potential tether like breakage effects in the thin film sails. Advocacy of further attention to these processes is emphasized so that plasma environmental mitigation will be instituted in photovoltaic sail design.

  16. 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.

  17. Simulation of upwind maneuvering of a sailing yacht

    Science.gov (United States)

    Harris, Daniel Hartrick

    A time domain maneuvering simulation of an IACC class yacht suitable for the analysis of unsteady upwind sailing including tacking is presented. The simulation considers motions in six degrees of freedom. The hydrodynamic and aerodynamic loads are calculated primarily with unsteady potential theory supplemented by empirical viscous models. The hydrodynamic model includes the effects of incident waves. Control of the rudder is provided by a simple rate feedback autopilot which is augmented with open loop additions to mimic human steering. The hydrodynamic models are based on the superposition of force components. These components fall into two groups, those which the yacht will experience in calm water, and those due to incident waves. The calm water loads are further divided into zero Froude number, or "double body" maneuvering loads, hydrostatic loads, gravitational loads, free surface radiation loads, and viscous/residual loads. The maneuvering loads are calculated with an unsteady panel code which treats the instantaneous geometry of the yacht below the undisturbed free surface. The free surface radiation loads are calculated via convolution of impulse response functions derived from seakeeping strip theory. The viscous/residual loads are based upon empirical estimates. The aerodynamic model consists primarily of a database of steady state sail coefficients. These coefficients treat the individual contributions to the total sail force of a number of chordwise strips on both the main and jib. Dynamic effects are modeled by using the instantaneous incident wind velocity and direction as the independent variables for the sail load contribution of each strip. The sail coefficient database was calculated numerically with potential methods and simple empirical viscous corrections. Additional aerodynamic load calculations are made to determine the parasitic contributions of the rig and hull. Validation studies compare the steady sailing hydro and aerodynamic loads

  18. Modeling and Solving the Liner Shipping Service Selection Problem

    DEFF Research Database (Denmark)

    Karsten, Christian Vad; Balakrishnan, Anant

    We address a tactical planning problem, the Liner Shipping Service Selection Problem (LSSSP), facing container shipping companies. Given estimated demand between various ports, the LSSSP entails selecting the best subset of non-simple cyclic sailing routes from a given pool of candidate routes...... to accurately model transshipment costs and incorporate routing policies such as maximum transit time, maritime cabotage rules, and operational alliances. Our hop-indexed arc flow model is smaller and easier to solve than path flow models. We outline a preprocessing procedure that exploits both the routing...... requirements and the hop limits to reduce problem size, and describe techniques to accelerate the solution procedure. We present computational results for realistic problem instances from the benchmark suite LINER-LIB....

  19. Cardiovascular load in off-shore sailing competition.

    Science.gov (United States)

    Bernardi, M; Felici, F; Marchetti, M; Marchettoni, P

    1990-06-01

    Blood pressure, heart rate, VO2 and lactate accumulation have been measured during the hauling of ropes that, in off shore sailing, very often implies MVC isometric effort. Measures have been taken alternatively on the boat or in laboratory with a boat simulator. It appears that energy output is moderate, lactic O2 debt not relevant and blood pressure is maintained quite unchanged due to the short duration of isometric effort. Cardiovascular load is therefore not heavy and sailing can be enlisted among aerobic recreational exercises.

  20. Escape trajectories of solar sails and general relativity

    Energy Technology Data Exchange (ETDEWEB)

    Kezerashvili, Roman Ya. [Physics Department, New York City College of Technology, City University of New York, 300 Jay Street, Brooklyn, NY 11201 (United States); Graduate School and University Center, City University of New York, 365 Fifth Avenue, New York, NY 10016 (United States); Vazquez-Poritz, Justin F., E-mail: jvazquez-poritz@citytech.cuny.ed [Physics Department, New York City College of Technology, City University of New York, 300 Jay Street, Brooklyn, NY 11201 (United States); Graduate School and University Center, City University of New York, 365 Fifth Avenue, New York, NY 10016 (United States)

    2009-11-16

    General relativity can have a significant impact on the long-range escape trajectories of solar sails deployed near the sun. For example, spacetime curvature in the vicinity of the sun can cause a solar sail traveling from about 4 solar radii to 2550 AU to be deflected by on the order of a million kilometers, and should therefore be taken into account at the beginning of the mission. There are a number of smaller general relativistic effects, such as frame dragging due to the slow rotation of the sun which can cause a deflection of more than one thousand kilometers.

  1. 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

  2. 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.

  3. Escape trajectories of solar sails and general relativity

    International Nuclear Information System (INIS)

    Kezerashvili, Roman Ya.; Vazquez-Poritz, Justin F.

    2009-01-01

    General relativity can have a significant impact on the long-range escape trajectories of solar sails deployed near the sun. For example, spacetime curvature in the vicinity of the sun can cause a solar sail traveling from about 4 solar radii to 2550 AU to be deflected by on the order of a million kilometers, and should therefore be taken into account at the beginning of the mission. There are a number of smaller general relativistic effects, such as frame dragging due to the slow rotation of the sun which can cause a deflection of more than one thousand kilometers.

  4. Strength Analysis on Ship Ladder Using Finite Element Method

    Science.gov (United States)

    Budianto; Wahyudi, M. T.; Dinata, U.; Ruddianto; Eko P., M. M.

    2018-01-01

    In designing the ship’s structure, it should refer to the rules in accordance with applicable classification standards. In this case, designing Ladder (Staircase) on a Ferry Ship which is set up, it must be reviewed based on the loads during ship operations, either during sailing or at port operations. The classification rules in ship design refer to the calculation of the structure components described in Classification calculation method and can be analysed using the Finite Element Method. Classification Regulations used in the design of Ferry Ships used BKI (Bureau of Classification Indonesia). So the rules for the provision of material composition in the mechanical properties of the material should refer to the classification of the used vessel. The analysis in this structure used program structure packages based on Finite Element Method. By using structural analysis on Ladder (Ladder), it obtained strength and simulation structure that can withstand load 140 kg both in static condition, dynamic, and impact. Therefore, the result of the analysis included values of safety factors in the ship is to keep the structure safe but the strength of the structure is not excessive.

  5. Economic Possibilities of Shipping though Northern Sea Route1

    Directory of Open Access Journals (Sweden)

    Sung-Woo Lee

    2014-12-01

    Full Text Available Global warming and climate change haves brought a new issue in the Arctic sea. Therefore, we can now explore new shipping routes through the Arctic Ocean instead of the existing commercial route. In particular, the Northern Sea Route (NSR is one of the feasible shipping routes and, has provided tremendous shipping benefits. If the NSR becomes commercialized, we will be able to save about 5,000 nautical miles in distance and sailing time. In this study, we will emphasize some of the important results on the possibility of commercializing the shipping route in the Arctic. The NSR may bring positive economic effects in terms of shipping distance and time. For example, when utilizing the NSR, the maximum cargo traffic between Asia and Europe is expected to be around 46 million TEU. However, we also need to consider an expensive passage fee that is currently imposed by Russia. In conclusion, we maintain our efforts to protect the environment in the Arctic, in terms of logistics, and we need to explore every possible avenue to bring possible economic benefits to the North Pacific countries.

  6. Guide to ship sanitation

    National Research Council Canada - National Science Library

    2011-01-01

    "The third edition of the Guide to Ship Sanitation presents the public health significance of ships in terms of disease and highlights the importance of applying appropriate control measures"--Back cover...

  7. Synthesis of stereoarray isotope labeled (SAIL) lysine via the "head-to-tail" conversion of SAIL glutamic acid.

    Science.gov (United States)

    Terauchi, Tsutomu; Kamikawai, Tomoe; Vinogradov, Maxim G; Starodubtseva, Eugenia V; Takeda, Mitsuhiro; Kainosho, Masatsune

    2011-01-07

    A stereoarray isotope labeled (SAIL) lysine, (2S,3R,4R,5S,6R)-[3,4,5,6-(2)H(4);1,2,3,4,5,6-(13)C(6);2,6-(15)N(2)]lysine, was synthesized by the "head-to-tail" conversion of SAIL-Glu, (2S,3S,4R)-[3,4-(2)H(2);1,2,3,4,5-(13)C(5);2-(15)N]glutamic acid, with high stereospecificities for all five chiral centers. With the SAIL-Lys in hand, the unambiguous simultaneous stereospecific assignments were able to be established for each of the prochiral protons within the four methylene groups of the Lys side chains in proteins.

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

    OpenAIRE

    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 potential source of the laser beam is a laser satellite that coverts solar power (in the inner solar system) or nuclear power (in the outer solar system) into laser power. Such a laser satellite (o...

  9. 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...

  10. Space Environmental Effects Testing and Characterization of the Candidate Solar Sail Material Aluminized Mylar

    Science.gov (United States)

    Edwards, D. L.; Hubbs, W. S.; Wertz, G. E.; Alstatt, R.; Munafo, Paul (Technical Monitor)

    2001-01-01

    The usage of solar sails as a propellantless propulsion system has been proposed for many years. The technical challenges associated with solar sails are fabrication of ultralightweight films, deploying the sails and controlling the spacecraft. Integral to all these challenges is the mechanical property integrity of the sail while exposed to the harsh environment of space. This paper describes testing and characterization of a candidate solar sail material, Aluminized Mylar. This material was exposed to a simulated Geosynchronous Transfer Orbit (GTO) and evaluated by measuring thermooptical and mechanical property changes. Testing procedures and results are presented.

  11. Traffic simulation based ship collision probability modeling

    Energy Technology Data Exchange (ETDEWEB)

    Goerlandt, Floris, E-mail: floris.goerlandt@tkk.f [Aalto University, School of Science and Technology, Department of Applied Mechanics, Marine Technology, P.O. Box 15300, FI-00076 AALTO, Espoo (Finland); Kujala, Pentti [Aalto University, School of Science and Technology, Department of Applied Mechanics, Marine Technology, P.O. Box 15300, FI-00076 AALTO, Espoo (Finland)

    2011-01-15

    Maritime traffic poses various risks in terms of human, environmental and economic loss. In a risk analysis of ship collisions, it is important to get a reasonable estimate for the probability of such accidents and the consequences they lead to. In this paper, a method is proposed to assess the probability of vessels colliding with each other. The method is capable of determining the expected number of accidents, the locations where and the time when they are most likely to occur, while providing input for models concerned with the expected consequences. At the basis of the collision detection algorithm lays an extensive time domain micro-simulation of vessel traffic in the given area. The Monte Carlo simulation technique is applied to obtain a meaningful prediction of the relevant factors of the collision events. Data obtained through the Automatic Identification System is analyzed in detail to obtain realistic input data for the traffic simulation: traffic routes, the number of vessels on each route, the ship departure times, main dimensions and sailing speed. The results obtained by the proposed method for the studied case of the Gulf of Finland are presented, showing reasonable agreement with registered accident and near-miss data.

  12. Recycling of merchant ships

    Directory of Open Access Journals (Sweden)

    Magdalena Klopott

    2013-12-01

    Full Text Available The article briefly outlines the issues concerning ship recycling. It highlights ships' high value as sources of steel scrap and non-ferrous metals, without omitting the fact that they also contain a range of hazardous substances. Moreover, the article also focuses on basic ship demolition methods and their environmental impact, as well as emphasizes the importance of “design for ship recycling” philosophy.

  13. Dutch Ships and Sailors

    NARCIS (Netherlands)

    de Boer, Victor; Hoekstra, F.G.; Leinenga, Jurjen; van Rossum, Matthias

    2014-01-01

    Dutch Ships and Sailors provides an infrastructure for maritime historical datasets, linking correlating data through semantic web technology. It brings together datasets related to recruitment and shipping in the East-India trade (mainly 18th century) and in the shipping of the northern provinces

  14. Reactors. Nuclear propulsion ships

    International Nuclear Information System (INIS)

    Fribourg, Ch.

    2001-01-01

    This article has for object the development of nuclear-powered ships and the conception of the nuclear-powered ship. The technology of the naval propulsion P.W.R. type reactor is described in the article B.N.3 141 'Nuclear Boilers ships'. (N.C.)

  15. A Computerized Navigation Support for Maneuvering Clustered Ship Groups in Close Proximity

    Directory of Open Access Journals (Sweden)

    Akira Kawaguchi

    2005-06-01

    Full Text Available The aim of this research is to investigate navigation behaviors and effects of interferences of multiple ocean-going vessels that share the same sailing course like a transport convoy. Detecting and evading other clusters in close proximity is one of the most important tasks in navigation as contacting these will potentially cause serious risks to the ship. Focus of this paper is to investigate computational capabilities added to the so-called ship cluster behavior model of our previous work. Enhancement is made to predict a risky situation and to guide for multiple ship clusters, enabling them to move safely and avoid contact with each other. Such improvement is critical, especially when the traffic becomes congested with a number of clustered ship groups moving to distinctive directions. Foundations for and preliminary experimental results of this study are discussed.

  16. Power Beamed Photon Sails: New Capabilities Resulting From Recent Maturation Of Key Solar Sail And High Power Laser Technologies

    International Nuclear Information System (INIS)

    Montgomery, Edward E. IV

    2010-01-01

    This paper revisits some content in the First International Symposium on Beamed Energy Propulsion in 2002 related to the concept of propellantless in-space propulsion utilizing an external high energy laser to provide momentum to an ultralightweight (gossamer) spacecraft. The design and construction of the NanoSail-D solar sail demonstration spacecraft has demonstrated in space flight hardware the concept of small, very light--yet capable--spacecraft. The results of the Joint High Power Solid State Laser (JHPSSL) have also increased the effectiveness and reduced the cost of an entry level laser source. This paper identifies the impact from improved system parameters on current mission applications.

  17. PartnerSHIPS: aligning your department with administration for smooth sailing.

    Science.gov (United States)

    Foy, Richard

    2015-03-01

    Healthy partnerships with hospital administration are essential for any neurodiagnostics program to experience growth and development. The differing backgrounds of business-oriented administrators and clinically oriented technologists can result in challenges with various departmental initiatives and lead to ineffective outcomes when seeking to balance high-quality, patient-oriented care with efficient and profitable operations. Over the course of a two-year period, The University of Texas Medical Branch at Galveston (UTMB Health) implemented several changes that have led to better patient care outcomes. These changes were possible because of a remarkably effective collaboration between neurodiagnostic technologists and hospital administration. Proven business principles were combined with evidence-based healthcare and clinical-practice guidelines to facilitate the following initiatives: 1. Combining EEG, electromyogram and nerve conduction studies (EMG/ NCV), intraoperative neurophysiological monitoring (IONM), long-term monitoring (LTM), and epilepsy monitoring unit (EMU) into one department. 2. Cross-training of technologists. 3. Policy and procedure development. 4. Strategic planning and relationship building. a. Partnering with local community college neurodiagnostic program. b. Building a per diem nurse (PRN)/float pool for coverage. c. Contracting for IONM services. Implementing these changes has resulted in many improvements within the department, such as an overall increase in procedure volumes, professional development and growth opportunities for staff and the availability of additional services for improved patient care.

  18. Nuclear merchant ship propulsion

    International Nuclear Information System (INIS)

    Schroeder, E.; Jager, W.; Schafstall, H.G.

    1977-01-01

    The operation of about 300 nuclear naval vessels has proven the feasibility of nuclear ship propulsion. Until now six non military ships have been built or are under construction. In the Soviet Union two nuclear icebreakers are in operation, and a third one is under construction. In the western world three prototype merchant ships have been built. Of these ships only the NS OTTO HAHN is in operation and provides valuable experience for future large scale use of nuclear merchant ship propulsion. In many countries studies and plans are made for future nuclear merchant ships. Types of vessels investigated are large containerships, tankers and specialized ships like icebreakers or ice-breaking ships. The future of nuclear merchant ship propulsion depends on three interrelated items: (1) nuclear ship technology; (2) economy of nuclear ship propulsion; (3) legal questions. Nuclear merchant ship technology is based until now on standard ship technology and light water reactor technology. Except for special questions due to the non-stationary type of the plant entirely new problems do not arise. This has been proven by the recent conceptual licensing procedure for a large nuclear containership in Germany. The economics of nuclear propulsion will be under discussion until they are proven by the operation of privately owned lead ships. Unsolved legal questions e.g. in connection with port entry permissions are at present another problem for nuclear shipping. Efforts are made to solve these questions on an international basis. The future development of nuclear energy electricity production in large land based plants will stimulate the employment of smaller units. Any future development of long distance sea transport will have to take this opportunity of a reliable and economic energy supply into account

  19. 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.

  20. Solar sail time-optimal interplanetary transfer trajectory design

    International Nuclear Information System (INIS)

    Gong Shengpin; Gao Yunfeng; Li Junfeng

    2011-01-01

    The fuel consumption associated with some interplanetary transfer trajectories using chemical propulsion is not affordable. A solar sail is a method of propulsion that does not consume fuel. Transfer time is one of the most pressing problems of solar sail transfer trajectory design. This paper investigates the time-optimal interplanetary transfer trajectories to a circular orbit of given inclination and radius. The optimal control law is derived from the principle of maximization. An indirect method is used to solve the optimal control problem by selecting values for the initial adjoint variables, which are normalized within a unit sphere. The conditions for the existence of the time-optimal transfer are dependent on the lightness number of the sail and the inclination and radius of the target orbit. A numerical method is used to obtain the boundary values for the time-optimal transfer trajectories. For the cases where no time-optimal transfer trajectories exist, first-order necessary conditions of the optimal control are proposed to obtain feasible solutions. The results show that the transfer time decreases as the minimum distance from the Sun decreases during the transfer duration. For a solar sail with a small lightness number, the transfer time may be evaluated analytically for a three-phase transfer trajectory. The analytical results are compared with previous results and the associated numerical results. The transfer time of the numerical result here is smaller than the transfer time from previous results and is larger than the analytical result.

  1. Project SAIL: An Evaluation of a Dropout Prevention Program.

    Science.gov (United States)

    Thompson, John L.; And Others

    Project SAIL (Student Advocates Inspire Learning) is a Title IV-C Project located in Hopkins, Minnesota, designed to prevent students from dropping out of school by keeping them successfully involved in the mainstream environment. This study presents a review of other dropout prevention approaches, describes the intervention strategies involved in…

  2. 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…

  3. SAIL: A Framework for Promoting Next-Generation Word Study

    Science.gov (United States)

    Ganske, Kathy

    2016-01-01

    This article introduces SAIL, an instructional framework designed to help teachers optimize students' learning during small-group word study instruction. Small-group word study interactions afford opportunities for teachers to engage students in thinking, talking, advancing vocabulary knowledge (including general academic vocabulary), and making…

  4. Design and Development of NEA Scout Solar Sail Deployer Mechanism

    Science.gov (United States)

    Sobey, Alexander R.; Lockett, Tiffany Russell

    2016-01-01

    The 6U (approx.10 cm x 20 cm x 30 cm) cubesat Near Earth Asteroid (NEA) Scout1, projected for launch in September 2018 aboard the maiden voyage of the Space Launch System, will utilize a solar sail as its main method of propulsion throughout its approx.3-year mission to a Near Earth Asteroid. Due to the extreme volume constraints levied onto the mission, an acutely compact solar sail deployment mechanism has been designed to meet the volume and mass constraints, as well as provide enough propulsive solar sail area and quality in order to achieve mission success. The design of such a compact system required the development of approximately half a dozen prototypes in order to identify unforeseen problems, advance solutions, and build confidence in the final design product. This paper focuses on the obstacles of developing a solar sail deployment mechanism for such an application and the lessons learned from a thorough development process. The lessons presented will have significant applications beyond the NEA Scout mission, such as the development of other deployable boom mechanisms and uses for gossamer-thin films in space.

  5. The Strategies To Advance the Internationalization of Learning (SAIL) Program.

    Science.gov (United States)

    Ebert, Kenneth B.; Burnett, Jane

    This report documents the Strategies to Advance the Internalization of Learning (SAIL) program developed at Michigan State University (MSU) to promote international, comparative, and cross-cultural learning and cross-cultural understanding in the university community. A total of 350 foreign and U.S. students who had international experience…

  6. Project SAIL: A Summer Program Brings History Alive for Students.

    Science.gov (United States)

    Hollingsworth, Patricia

    2001-01-01

    This project describes Project SAIL (Schools for Active Interdisciplinary Learning), a federally funded project providing in-depth staff development during a 3-week summer program for teachers, parents, and their gifted/talented economically disadvantaged students. The program theme, "Searching for Patterns in History," has been used with students…

  7. 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.

  8. SETI VIA LEAKAGE FROM LIGHT SAILS IN EXOPLANETARY SYSTEMS

    International Nuclear Information System (INIS)

    Guillochon, James; Loeb, Abraham

    2015-01-01

    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)

  9. SETI via Leakage from Light Sails in Exoplanetary Systems

    Science.gov (United States)

    Guillochon, James; Loeb, Abraham

    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).

  10. Boltzmann electron PIC simulation of the E-sail effect

    Directory of Open Access Journals (Sweden)

    P. Janhunen

    2015-12-01

    Full Text Available The solar wind electric sail (E-sail is a planned in-space propulsion device that uses the natural solar wind momentum flux for spacecraft propulsion with the help of long, charged, centrifugally stretched tethers. The problem of accurately predicting the E-sail thrust is still somewhat open, however, due to a possible electron population trapped by the tether. Here we develop a new type of particle-in-cell (PIC simulation for predicting E-sail thrust. In the new simulation, electrons are modelled as a fluid, hence resembling hybrid simulation, but in contrast to normal hybrid simulation, the Poisson equation is used as in normal PIC to calculate the self-consistent electrostatic field. For electron-repulsive parts of the potential, the Boltzmann relation is used. For electron-attractive parts of the potential we employ a power law which contains a parameter that can be used to control the number of trapped electrons. We perform a set of runs varying the parameter and select the one with the smallest number of trapped electrons which still behaves in a physically meaningful way in the sense of producing not more than one solar wind ion deflection shock upstream of the tether. By this prescription we obtain thrust per tether length values that are in line with earlier estimates, although somewhat smaller. We conclude that the Boltzmann PIC simulation is a new tool for simulating the E-sail thrust. This tool enables us to calculate solutions rapidly and allows to easily study different scenarios for trapped electrons.

  11. 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)

  12. Starship Sails Propelled by Cost-Optimized Directed Energy

    Science.gov (United States)

    Benford, J.

    Microwave and laser-propelled sails are a new class of spacecraft using photon acceleration. It is the only method of interstellar flight that has no physics issues. Laboratory demonstrations of basic features of beam-driven propulsion, flight, stability (`beam-riding'), and induced spin, have been completed in the last decade, primarily in the microwave. It offers much lower cost probes after a substantial investment in the launcher. Engineering issues are being addressed by other applications: fusion (microwave, millimeter and laser sources) and astronomy (large aperture antennas). There are many candidate sail materials: carbon nanotubes and microtrusses, beryllium, graphene, etc. For acceleration of a sail, what is the cost-optimum high power system? Here the cost is used to constrain design parameters to estimate system power, aperture and elements of capital and operating cost. From general relations for cost-optimal transmitter aperture and power, system cost scales with kinetic energy and inversely with sail diameter and frequency. So optimal sails will be larger, lower in mass and driven by higher frequency beams. Estimated costs include economies of scale. We present several starship point concepts. Systems based on microwave, millimeter wave and laser technologies are of equal cost at today's costs. The frequency advantage of lasers is cancelled by the high cost of both the laser and the radiating optic. Cost of interstellar sailships is very high, driven by current costs for radiation source, antennas and especially electrical power. The high speeds necessary for fast interstellar missions make the operating cost exceed the capital cost. Such sailcraft will not be flown until the cost of electrical power in space is reduced orders of magnitude below current levels.

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

    Science.gov (United States)

    Bak, Sera; Yoo, Jaehoon; Song, Chang Yong

    2013-06-01

    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.

  14. 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.

  15. A Direct and Fast Methodology for Ship Recognition in Sentinel-2 Multispectral Imagery

    Directory of Open Access Journals (Sweden)

    Henning Heiselberg

    2016-12-01

    Full Text Available The European Space Agency satellite Sentinel-2 provides multispectral images with pixel sizes down to 10 m. This high resolution allows for ship detection and recognition by determining a number of important ship parameters. We are able to show how a ship position, its heading, length and breadth can be determined down to a subpixel resolution. If the ship is moving, its velocity can also be determined from its Kelvin waves. The 13 spectrally different visual and infrared images taken using multispectral imagery (MSI are “fingerprints” that allow for the recognition and identification of ships. Furthermore, the multispectral image profiles along the ship allow for discrimination between the ship, its turbulent wakes, and the Kelvin waves, such that the ship’s length and breadth can be determined more accurately even when sailing. The ship’s parameters are determined by using satellite imagery taken from several ships, which are then compared to known values from the automatic identification system. The agreement is on the order of the pixel resolution or better.

  16. Network Design for Container Shipping Using Cutting Planes

    DEFF Research Database (Denmark)

    The network design problem in container shipping is of increasing importance in the strongly competitive markets where potential cost reductions are of the utmost importance. We combine the network design and fleet assignment problem into a mixed integer linear programming model minimizing the ov...... the fact that the route of a ship allows for subtours, we introduce the concept of pseudo-simple routes. To solve the problem we use a branch and cut solution method using clover and capacity cuts we defined for the problem.......The network design problem in container shipping is of increasing importance in the strongly competitive markets where potential cost reductions are of the utmost importance. We combine the network design and fleet assignment problem into a mixed integer linear programming model minimizing...... the overall cost. The real-life container shipping network design problem differs in several ways from the standard network design problem. Examples of these differences are the cyclic routes of vessels and the fact that a route is continuously sailed for a given forecast period. To model these real...

  17. Energy saving in the shipping industry; Energiebesparing in de scheepvaart

    Energy Technology Data Exchange (ETDEWEB)

    Gilijamse, J.; Van Wijngaarden, W.

    2010-01-15

    The German shipping industry pays much attention to sustainability and efficiency. More strict international environmental requirements often encourage shipping companies to incite shipbuilders towards innovation. Yet some shipbuilders are consciously adopting a frontrunner's role in developing prototypes of energy efficient ships. In addition to the return of modern versions of sailing ships these projects also entail hydrogen, wind energy and new materials, but also exploring the ocean with satellites to gather detailed information used for optimizing the itinerary. [Dutch] Er is in de Duitse scheepsbouwindustrie veel aandacht voor duurzaamheid en efficientie. Strengere internationale milieu-eisen zijn vaak aanleiding voor rederijen om scheepsbouwers tot innovatie aan te zetten. Maar enkele reders nemen bewust een voorlopersrol en ontwikkelen prototypes van energie-efficientere schepen. Naast de terugkeer van moderne versies van zeilschepen gaat het hierbij om projecten met waterstof, windenergie en nieuwe materialen, maar ook om het verkennen van de oceaan met satellieten om nauwkeurige gegevens te vergaren voor de optimalisatie van vaarroutes.

  18. Performance of Ships and Offshore Structures in Waves

    Directory of Open Access Journals (Sweden)

    Shukui Liu

    2012-01-01

    for predicting large amplitude motions of ships and floating structures in response to incoming waves in the frame of potential theory. The developed alternative set of time domain methods simulate the hydrodynamic forces acting on ships advancing in waves with constant speed. For motions’ simulation, the diffraction forces and radiation forces are calculated up to the mean wetted surface, while the Froude-Krylov forces and hydrostatic restoring forces are calculated up to the undisturbed incident wave surface in case of large incident wave amplitude. This enables the study of the above waterline hull form effect. Characteristic case studies on simulating the hydrodynamic forces and motions of standard type of ships have been conducted for validation purpose. Good agreement with other numerical codes and experimental data has been observed. Furthermore, the added resistance of ships in waves can be calculated by the presented methods. This capability supports the increased demand of this type of tools for the proper selection of engine/propulsion systems accounting for ship’s performance in realistic sea conditions, or when optimizing ship’s sailing route for minimum fuel consumption and toxic gas emissions.

  19. Buckling of Ship Structures

    CERN Document Server

    Shama, Mohamed

    2013-01-01

    Buckling of Ship Structures presents a comprehensive analysis of the buckling problem of ship structural members. A full analysis of the various types of loadings and stresses imposed on ship plating and primary and secondary structural members is given. The main causes and consequences of the buckling mode of failure of ship structure and the methods commonly used to control buckling failure are clarified. This book contains the main equations required to determine the critical buckling stresses for both ship plating and the primary and secondary stiffening structural members. The critical buckling stresses are given for ship plating subjected to the induced various types of loadings and having the most common boundary conditions encountered in ship structures.  The text bridges the gap existing in most books covering the subject of buckling of ship structures in the classical analytical format, by putting the emphasis on the practical methods required to ensure safety against buckling of ship structur...

  20. Emissions from international shipping. Pt. 2: Impact of future technologies - scenarios for the years 2020 and 2050

    International Nuclear Information System (INIS)

    Eyring, V.; Lauer, A.; Lemper, B.

    2004-01-01

    We use the today's fleet-average emission factors of the most important ship exhausts to calculate emission scenarios for the future. To develop plausible future scenarios we first discuss upcoming regulations and compliance with future regulations through technological improvements. We present geographically resolved emission inventory forecast scenarios for the years 2020 and 2050. The scenarios are based on some very strict assumptions of future ship traffic demand and technological improvements. The future ship traffic demand scenario is mainly determined by the economic growth and the growth in world seaborne trade and distinguishes between different ship types. The annual growth rates of sea trade volumes and expected vessel traffic density is assumed to be smaller for today's most frequently sailed routes (in particular east-west-trades) than for those that are currently less frequently sailed (in particular south-north-trades). This leads to an adjustment of the number of ships sailing the different shipping routes in 2020 and even stronger in 2050. For the future technology scenarios we assume a diesel-only fleet in 2020 resulting in an estimated fuel consumption of 422 million metric tons (Mt) and 1226 Tg CO 2 emissions. For 2050 one scenario for fuel consumption assumes that 25% of the fuel consumed by a diesel-only fleet can be saved by using future alternative propulsion plants, resulting in a fuel consumption of 422 Mt and 1339 Tg CO 2 emissions in 2050. The other scenario is a business-as-usual scenario for a diesel-only fleet even in 2050 and gives an estimate of 646 Mt and 1783 Tg CO 2 emissions in 2050. Dependent on how rapid technology improvements for diesel engines are introduced we present four different technology scenarios. (orig.)

  1. Accelerator-Based PIXE and STIM Analysis of Candidate Solar Sail Materials

    International Nuclear Information System (INIS)

    Hollerman, W.A.; Stanaland, T.L.; Boudreaux, P.; Elberson, L.; Fontenot, J.; Gates, E.; Greco, R.; McBride, M.; Woodward, A.; Edwards, D.

    2003-01-01

    Solar sailing is a unique form of propulsion where a spacecraft gains momentum from incident photons. A totally reflective sail experiences a pressure of 9.1 μPa at a distance of 1 AU from the Sun. Since sails are not limited by reaction mass, they provide continual acceleration, reduced only by the lifetime of the lightweight film in the space environment and the distance to the Sun. Practical solar sails can expand the number of possible missions, enabling new concepts that are difficult by conventional means. One of the current challenges is to develop strong, lightweight, and radiation resistant sail materials. This paper will discuss initial results from a Particle Induced X-Ray Emission (PIXE) and Scanning Transmission Ion Microscopy (STIM) analysis of candidate solar sail materials

  2. Unfrozen sea : sailing the northwest passage

    International Nuclear Information System (INIS)

    Byers, M.

    2007-01-01

    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

  3. Application of SAIL phenylalanine and tyrosine with alternative isotope-labeling patterns for protein structure determination

    Energy Technology Data Exchange (ETDEWEB)

    Takeda, Mitsuhiro [Nagoya University, Structural Biology Research Center, Graduate School of Science (Japan); Ono, Akira M.; Terauchi, Tsutomu [SAIL Technologies Co., Inc. (Japan); Kainosho, Masatsune, E-mail: kainosho@nmr.chem.metro-u.ac.j [Nagoya University, Structural Biology Research Center, Graduate School of Science (Japan)

    2010-01-15

    The extensive collection of NOE constraint data involving the aromatic ring signals is essential for accurate protein structure determination, although it is often hampered in practice by the pervasive signal overlapping and tight spin couplings for aromatic rings. We have prepared various types of stereo-array isotope labeled phenylalanines ({epsilon}- and {zeta}-SAIL Phe) and tyrosine ({epsilon}-SAIL Tyr) to overcome these problems (Torizawa et al. 2005), and proven that these SAIL amino acids provide dramatic spectral simplification and sensitivity enhancement for the aromatic ring NMR signals. In addition to these SAIL aromatic amino acids, we recently synthesized {delta}-SAIL Phe and {delta}-SAIL Tyr, which allow us to observe and assign {delta}-{sup 13}C/{sup 1}H signals very efficiently. Each of the various types of SAIL Phe and SAIL Tyr yields well-resolved resonances for the {delta}-, {epsilon}- or {zeta}-{sup 13}C/{sup 1}H signals, respectively, which can readily be assigned by simple and robust pulse sequences. Since the {delta}-, {epsilon}-, and {zeta}-proton signals of Phe/Tyr residues give rise to complementary NOE constraints, the concomitant use of various types of SAIL-Phe and SAIL-Tyr would generate more accurate protein structures, as compared to those obtained by using conventional uniformly {sup 13}C, {sup 15}N-double labeled proteins. We illustrated this with the case of an 18.2 kDa protein, Escherichia coli peptidyl-prolyl cis-trans isomerase b (EPPIb), and concluded that the combined use of {zeta}-SAIL Phe and {epsilon}-SAIL Tyr would be practically the best choice for protein structural determinations.

  4. Application of SAIL phenylalanine and tyrosine with alternative isotope-labeling patterns for protein structure determination.

    Science.gov (United States)

    Takeda, Mitsuhiro; Ono, Akira M; Terauchi, Tsutomu; Kainosho, Masatsune

    2010-01-01

    The extensive collection of NOE constraint data involving the aromatic ring signals is essential for accurate protein structure determination, although it is often hampered in practice by the pervasive signal overlapping and tight spin couplings for aromatic rings. We have prepared various types of stereo-array isotope labeled phenylalanines (epsilon- and zeta-SAIL Phe) and tyrosine (epsilon-SAIL Tyr) to overcome these problems (Torizawa et al. 2005), and proven that these SAIL amino acids provide dramatic spectral simplification and sensitivity enhancement for the aromatic ring NMR signals. In addition to these SAIL aromatic amino acids, we recently synthesized delta-SAIL Phe and delta-SAIL Tyr, which allow us to observe and assign delta-(13)C/(1)H signals very efficiently. Each of the various types of SAIL Phe and SAIL Tyr yields well-resolved resonances for the delta-, epsilon- or zeta-(13)C/(1)H signals, respectively, which can readily be assigned by simple and robust pulse sequences. Since the delta-, epsilon-, and zeta-proton signals of Phe/Tyr residues give rise to complementary NOE constraints, the concomitant use of various types of SAIL-Phe and SAIL-Tyr would generate more accurate protein structures, as compared to those obtained by using conventional uniformly (13)C, (15)N-double labeled proteins. We illustrated this with the case of an 18.2 kDa protein, Escherichia coli peptidyl-prolyl cis-trans isomerase b (EPPIb), and concluded that the combined use of zeta-SAIL Phe and epsilon-SAIL Tyr would be practically the best choice for protein structural determinations.

  5. Application of SAIL phenylalanine and tyrosine with alternative isotope-labeling patterns for protein structure determination

    International Nuclear Information System (INIS)

    Takeda, Mitsuhiro; Ono, Akira M.; Terauchi, Tsutomu; Kainosho, Masatsune

    2010-01-01

    The extensive collection of NOE constraint data involving the aromatic ring signals is essential for accurate protein structure determination, although it is often hampered in practice by the pervasive signal overlapping and tight spin couplings for aromatic rings. We have prepared various types of stereo-array isotope labeled phenylalanines (ε- and ζ-SAIL Phe) and tyrosine (ε-SAIL Tyr) to overcome these problems (Torizawa et al. 2005), and proven that these SAIL amino acids provide dramatic spectral simplification and sensitivity enhancement for the aromatic ring NMR signals. In addition to these SAIL aromatic amino acids, we recently synthesized δ-SAIL Phe and δ-SAIL Tyr, which allow us to observe and assign δ- 13 C/ 1 H signals very efficiently. Each of the various types of SAIL Phe and SAIL Tyr yields well-resolved resonances for the δ-, ε- or ζ- 13 C/ 1 H signals, respectively, which can readily be assigned by simple and robust pulse sequences. Since the δ-, ε-, and ζ-proton signals of Phe/Tyr residues give rise to complementary NOE constraints, the concomitant use of various types of SAIL-Phe and SAIL-Tyr would generate more accurate protein structures, as compared to those obtained by using conventional uniformly 13 C, 15 N-double labeled proteins. We illustrated this with the case of an 18.2 kDa protein, Escherichia coli peptidyl-prolyl cis-trans isomerase b (EPPIb), and concluded that the combined use of ζ-SAIL Phe and ε-SAIL Tyr would be practically the best choice for protein structural determinations.

  6. 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.

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

    Science.gov (United States)

    Johnson, Les; Lockett, Tiffany

    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 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, 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. NEA Scout uses a 6U cubesat (to be provided by NASA's Jet Propulsion Laboratory), an 86 m(exp. 2) solar sail and will weigh less than 12 kilograms. NEA Scout will be launched on the first flight of the Space Launch System in 2018. 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 approximately 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 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 sail technology in general.

  8. 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.

  9. Optimal heliocentric trajectories for solar sail with minimum area

    Science.gov (United States)

    Petukhov, Vyacheslav G.

    2018-05-01

    The fixed-time heliocentric trajectory optimization problem is considered for planar solar sail with minimum area. Necessary optimality conditions are derived, a numerical method for solving the problem is developed, and numerical examples of optimal trajectories to Mars, Venus and Mercury are presented. The dependences of the minimum area of the solar sail from the date of departure from the Earth, the time of flight and the departing hyperbolic excess of velocity are analyzed. In particular, for the rendezvous problem (approaching a target planet with zero relative velocity) with zero departing hyperbolic excess of velocity for a flight duration of 1200 days it was found that the minimum area-to-mass ratio should be about 12 m2/kg for trajectory to Venus, 23.5 m2/kg for the trajectory to Mercury and 25 m2/kg for trajectory to Mars.

  10. 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.

  11. 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.

  12. 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.

  13. Crushing Strength of Ship Structures

    DEFF Research Database (Denmark)

    Cerup-Simonsen, Bo; Abramowicz, W.; Høstgaard-Brene, C.N.S.

    1999-01-01

    The crushing response of ship structures is of primary importance to the designers and practicing engineers concerned with accidental loading and accident reconstruction of marine vehicles. Ship to-ship collisions, ship-harbor infrastructure interaction or ship-offshore structure interaction are ...

  14. A UKSeRP for SAIL: striking a balance

    Directory of Open Access Journals (Sweden)

    Kerina Jones

    2017-04-01

    The SAIL UKSeRP represents a powerful analytical environment within a privacy-protecting safe haven and secure remote access system which has been designed to be scalable and adaptable to meet the needs of the rapidly growing data linkage community. Further challenges lie ahead as the landscape develops and emerging data types become more available. UKSeRP technology is available and customisable for other use cases within the UK and international jurisdictions, to operate within their respective governance frameworks.

  15. Sail training: an innovative approach to graduate nurse preceptor development.

    Science.gov (United States)

    Nicol, Pam; Young, Melisa

    2007-01-01

    A 1-day sail-training program that aims to increase graduate nurse preceptor skills was evaluated. Preliminary results suggest that this experiential learning is an effective way to develop graduate nurse preceptors. Awareness of graduate nurses' needs has been heightened, and skills in clinical teaching have been developed. It is indicated from the limited results that the outcomes are sustained over time, but further evaluation is needed.

  16. Shipping Information Pipeline

    DEFF Research Database (Denmark)

    Jensen, Thomas; Vatrapu, Ravi

    2015-01-01

    and national borders within international shipping which is a rather complex domain. The intellectual objective is to generate and evaluate the efficacy and effectiveness of design principles for inter-organizational information infrastructures in the international shipping domain that can have positive...

  17. Handbook of nuclear ships

    International Nuclear Information System (INIS)

    1981-03-01

    First, the government organs and other organizations related to nuclear ships and their tasks are described. The fundamental plan for the development of nuclear ships had been determined in July, 1963, and was revised three times thereafter. However in December, 1980, new determination to carry out the research works also was made. The course of the construction of the nuclear ship ''Mutsu'' from 1955 to 1980, the main particulars of the nuclear ship ''Mutsu'' and the drawing of the general arrangement are shown. The designated port for berthing the Mutsu was completed in 1972 in Ominato, Aomori Prefecture, but after the happening of radiation leak during the trial operation of the Mutsu in 1974, it was agreed to remove the port. The main works to be carried out at the port and the port facilities are explained. The progress of the examination of safety of the Mutsu and the result, the test of raising the power output carried out in 1974, and the course of selecting the port for making the repair works of the Mutsu are described. The law concerning Japan Nuclear Ship Research and Development Agency had been instituted in 1963, and was revised four times thereafter. The change of the budget for the tests and researches related to nuclear ships in Japan is shown. The state of development of nuclear ships in foreign countries, the international organs related to atomic energy, shipping, shipbuilding and energy, and chronological table are introduced. (Kako, I.)

  18. Effective and Safe Ships

    DEFF Research Database (Denmark)

    Pedersen, Preben Terndrup; Amdahl, Jørgen; Rutgersson, Olle

    1996-01-01

    A Joint Nordic Research project "Effecive and Safe Ships" is presented. The project is aiming to develop methods and tools for quantitative evaluation fo ship safety. This report is the report of the preliminary phase where the plan for the main project is developed. The objectives of the project...

  19. On Possibility of Direct Asteroid Deflection by Electric Solar Wind Sail

    Science.gov (United States)

    Merikallio, Sini; Janhunen, Pekka

    2010-05-01

    The Electric Solar Wind Sail (E-sail) is a new propulsion method for interplanetary travel which was invented in 2006 and is currently under development. The E-sail uses charged tethers to extract momentum from the solar wind particles to obtain propulsive thrust. According to current estimates, the E-sail is 2-3 orders of magnitude better than traditional propulsion methods (chemical rockets and ion engines) in terms of produced lifetime-integrated impulse per propulsion system mass. Here we analyze the problem of using the E-sail for directly deflecting an Earth-threatening asteroid. The problem then culminates into how to attach the E-sail device to the asteroid. We assess a number of alternative attachment strategies and arrive at a recommendation of using the gravity tractor method because of its workability for a wide variety of asteroid types. We also consider possible techniques to scale up the E-sail force beyond the baseline one Newton level to deal with more imminent or larger asteroid or cometary threats. As a baseline case we consider a 3 million ton asteroid which can be deflected with a baseline 1 N E-sail in 5-10 years. Once developed, the E-sail would appear to provide a safe and reasonably low-cost way of deflecting dangerous asteroids and other heavenly bodies in cases where the collision threat becomes known several years in advance.

  20. 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...

  1. Reduction of Martian Sample Return Mission Launch Mass with Solar Sail Propulsion

    Science.gov (United States)

    Russell, Tiffany E.; Heaton, Andrew; Thomas, Scott; Thomas, Dan; Young, Roy; Baysinger, Mike; Capizzo, Pete; Fabisinski, Leo; Hornsby, Linda; Maples, Dauphne; hide

    2013-01-01

    Solar sails have the potential to provide mass and cost savings for spacecraft traveling within the inner solar system. Companies like L'Garde have demonstrated sail manufacturability and various in-space deployment methods. The purpose of this study was to evaluate a current Mars sample return architecture and to determine how cost and mass would be reduced by incorporating a solar sail propulsion system. The team validated the design proposed by L'Garde, and scaled the design based on a trajectory analysis. Using the solar sail design reduced the required mass, eliminating one of the three launches required in the original architecture.

  2. 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.

  3. Dynamics and Control of a Flexible Solar Sail

    Directory of Open Access Journals (Sweden)

    Jiafu Liu

    2014-01-01

    Full Text Available Solar sail can merely make use of solar radiation pressure (SRP force as the thrust for space missions. The attitude dynamics is obtained for the highly flexible solar sail with control vanes, sliding masses, and a gimbaled control boom. The vibration equations are derived considering the geometric nonlinearity of the sail structure subjected to the forces generated by the control vanes, solar radiation pressure (SRP, and sliding masses. Then the dynamic models for attitude/vibration controller design and dynamic simulation are obtained, respectively. The linear quadratic regulator (LQR based and optimal proportional-integral (PI based controllers are designed for the coupled attitude/vibration models with constant disturbance torques caused by the center-of-mass (cm/center-of-pressure (cp offset, respectively. It can be concluded from the theoretical analysis and simulation results that the optimal PI based controller performs better than the LQR based controller from the view of eliminating the steady-state errors. The responses with and without the geometrical nonlinearity are performed, and the differences are observed and analyzed. And some suggestions are also presented.

  4. Interplanetary Radiation and Internal Charging Environment Models for Solar Sails

    Science.gov (United States)

    Minow, Joseph I.; Altstatt, Richard L.; NeegaardParker, Linda

    2005-01-01

    A Solar Sail Radiation Environment (SSRE) model has been developed for defining charged particle environments over an energy range from 0.01 keV to 1 MeV for hydrogen ions, helium ions, and electrons. The SSRE model provides the free field charged particle environment required for characterizing energy deposition per unit mass, charge deposition, and dose rate dependent conductivity processes required to evaluate radiation dose and internal (bulk) charging processes in the solar sail membrane in interplanetary space. Solar wind and energetic particle measurements from instruments aboard the Ulysses spacecraft in a solar, near-polar orbit provide the particle data over a range of heliospheric latitudes used to derive the environment that can be used for radiation and charging environments for both high inclination 0.5 AU Solar Polar Imager mission and the 1.0 AU L1 solar missions. This paper describes the techniques used to model comprehensive electron, proton, and helium spectra over the range of particle energies of significance to energy and charge deposition in thin (less than 25 micrometers) solar sail materials.

  5. Shipping Information Pipeline

    DEFF Research Database (Denmark)

    Jensen, Thomas

    to creating a more efficient shipping industry, and a number of critical issues are identified. These include that shipments depend on shipping information, that shipments often are delayed due to issues with documentation, that EDI messages account for only a minor part of the needed information......This thesis applies theoretical perspectives from the Information Systems (IS) research field to propose how Information Technology (IT) can improve containerized shipping. This question is addressed by developing a set of design principles for an information infrastructure for sharing shipping...... information named the Shipping Information Pipeline (SIP). Review of the literature revealed that IS research prescribed a set of meta-design principles, including digitalization and digital collaboration by implementation of Inter-Organizational Systems based on Electronic Data Interchange (EDI) messages...

  6. Nuclear ships and their safety

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1961-04-15

    Several aspects of nuclear ship propulsion, with special reference to nuclear safety, were discussed at an international symposium at Taormina, Italy, from 14-18 November 1960. Discussions on specific topics are conducted, grouped under the following headings: Economics and National Activities in Nuclear Ship Propulsion; International Problems and General Aspects of Safety for Nuclear Ships; Nuclear Ship Projects from the Angle of Safety; Ship Reactor Problems; Sea Motion and Hull Problems; Maintenance and Refuelling Problems; and Safety Aspects of Nuclear Ship Operation.

  7. Hydrodynamics of Ship Propellers

    DEFF Research Database (Denmark)

    Breslin, John P.; Andersen, Poul

    This book deals with flows over propellers operating behind ships, and the hydrodynamic forces and moments which the propeller generates on the shaft and on the ship hull.The first part of the text is devoted to fundamentals of the flow about hydrofoil sections (with and without cavitation...... of an intermittently cavitating propeller in a wake and the pressures and forces it exerts on the shaft and on the ship hull is examined. A final chapter discusses the optimization of efficiency of compound propulsors. The authors have taken care to clearly describe physical concepts and mathematical steps. Appendices...

  8. Vertical-axis turbine/propeller for ship propulsion

    Energy Technology Data Exchange (ETDEWEB)

    Barkla, H.M.

    1984-01-01

    There are so many variables in the design and operating conditions of a vertical-axis turbine/propeller for the propulsion of a ship by wind that a preliminary study is offered, based on two simplified models. Study of a linear motion of blades in air and water shows optimum conditions for blade-speed and blade-incidence. Analysis of the second, cyclical model is simplified by the assumption of constant angles of incidence. While the logical superiority of the vertical-axis system, with its low transmission loss, may not alone give it the advantage over all other systems in upwind and downwind sailing, there are indications that in the beam wind it is in a class of its own; the Voith-Schneider-Type propeller then produces a thrust with a major component to windward, so that the combined unit leaves little or no athwartships force.

  9. Uncertainty quantification of CO2 emission reduction for maritime shipping

    International Nuclear Information System (INIS)

    Yuan, Jun; Ng, Szu Hui; Sou, Weng Sut

    2016-01-01

    The International Maritime Organization (IMO) has recently proposed several operational and technical measures to improve shipping efficiency and reduce the greenhouse gases (GHG) emissions. The abatement potentials estimated for these measures have been further used by many organizations to project future GHG emission reductions and plot Marginal Abatement Cost Curves (MACC). However, the abatement potentials estimated for many of these measures can be highly uncertain as many of these measures are new, with limited sea trial information. Furthermore, the abatements obtained are highly dependent on ocean conditions, trading routes and sailing patterns. When the estimated abatement potentials are used for projections, these ‘input’ uncertainties are often not clearly displayed or accounted for, which can lead to overly optimistic or pessimistic outlooks. In this paper, we propose a methodology to systematically quantify and account for these input uncertainties on the overall abatement potential forecasts. We further propose improvements to MACCs to better reflect the uncertainties in marginal abatement costs and total emissions. This approach provides a fuller and more accurate picture of abatement forecasts and potential reductions achievable, and will be useful to policy makers and decision makers in the shipping industry to better assess the cost effective measures for CO 2 emission reduction. - Highlights: • We propose a systematic method to quantify uncertainty in emission reduction. • Marginal abatement cost curves are improved to better reflect the uncertainties. • Percentage reduction probability is given to determine emission reduction target. • The methodology is applied to a case study on maritime shipping.

  10. Designing Adaptable Ships: Modularity and Flexibility in Future Ship Designs

    Science.gov (United States)

    2016-01-01

    with motors, belts, shafts , seals, valves, hose spindles , and switches. If ship installation is not installed, the system will be status quo. Ship...Impact: the current centrifugal purifiers (Alfa-Laval) have experienced frequent failures with motor, belts, shafts , seals, valves, hose spindles ... Designing Adaptable Ships Modularity and Flexibility in Future Ship Designs John F. Schank, Scott Savitz, Ken Munson, Brian Perkinson, James

  11. SOLAR SAIL PROPULSION SENSITIVITY TO MEMBRANE SHAPE AND OPTICAL PROPERTIES USING THE SOLAR VECTORING EVALUATION TOOL (SVET)

    Science.gov (United States)

    Ewing, Anthony

    2005-01-01

    Solar sail propulsive performance is dependent on sail membrane optical properties and on sail membrane shape. Assumptions of an ideal sail (flat, perfect reflector) can result in errors which can affect spacecraft control, trajectory analyses, and overall evaluation of solar sail performance. A MATLAB(R) program has been developed to generate sail shape point cloud files for two square-architecture solar sail designs. Simple parabolic profiles are assumed for sail shape under solar pressure loading. These files are then input into the Solar Vectoring Evaluation Tool (SVET) software to determine the propulsive force vector, center of pressure, and moments about the sail body axes as a function of sail shape and optical properties. Also, the impact of the center-line angle, due to non-perfect optical properties, is addressed since this constrains sail force vector cone angle and is often overlooked when assuming ideal-reflector membranes. Preliminary sensitivity analysis using these tools aids in determining the key geometric and optical parameters that drive solar sail propulsive performance.

  12. 76 FR 62298 - Special Local Regulations; Line of Sail Marine Parade, East River and Brunswick River, Brunswick, GA

    Science.gov (United States)

    2011-10-07

    ...-AA08 Special Local Regulations; Line of Sail Marine Parade, East River and Brunswick River, Brunswick... during the Line of Sail Marine Parade on Saturday, October 8, 2011. The marine parade will consist of... did not receive notice of the Line of Sail Marine Parade with sufficient time to publish an NPRM or to...

  13. 77 FR 18984 - Special Local Regulation for Marine Events; Yorktown Parade of Sail, York River; Yorktown, VA

    Science.gov (United States)

    2012-03-29

    ...-AA08 Special Local Regulation for Marine Events; Yorktown Parade of Sail, York River; Yorktown, VA... proposes to establish special local regulation during the Yorktown Parade of Sail, a parade of five tall... sponsor the ``Yorktown Parade of Sail'' on the waters of York River. The event will consist of...

  14. Optimization in liner shipping

    DEFF Research Database (Denmark)

    Brouer, Berit Dangaard; Karsten, Christian Vad; Pisinger, David

    2017-01-01

    Seaborne trade is the lynchpin in almost every international supply chain, and about 90% of non-bulk cargo worldwide is transported by container. In this survey we give an overview of data-driven optimization problems in liner shipping. Research in liner shipping is motivated by a need for handling...... still more complex decision problems, based on big data sets and going across several organizational entities. Moreover, liner shipping optimization problems are pushing the limits of optimization methods, creating a new breeding ground for advanced modelling and solution methods. Starting from liner...... shipping network design, we consider the problem of container routing and speed optimization. Next, we consider empty container repositioning and stowage planning as well as disruption management. In addition, the problem of bunker purchasing is considered in depth. In each section we give a clear problem...

  15. Civilian nuclear ships

    International Nuclear Information System (INIS)

    Oelgaard, P.L.

    1993-03-01

    This report contains a review of the information available on nuclear powered ships, built for civilian purposes. In the introduction a short discussion is given of the reasons for the limited use of nuclear ships for these purposes. In the second section a brief review is presented of data for the three experimental/merchant ships build by the United States, Germany and Japan, i.e. NS Savannah, NS Otto Hahn and NS Mutsu. In the third section the Soviet/Russian icebreaker NS Lenin is considered. Its design, operational experience and the introduction of a new nuclear propulsion plant is reviewed. In the fourth section the newer Soviet/Russian icebreakers with nuclear propulsion are considered. Finally design of the Soviet/Russian icebreaker transport/container ship NS Sevmorput is reviewed in the fifth section. The future Russian plans for nuclear vessels for the arctic waters are briefly discussed. (au)

  16. Ship propulsion reactors technology

    International Nuclear Information System (INIS)

    Fribourg, Ch.

    2002-01-01

    This paper takes the state of the art on ship propulsion reactors technology. The french research programs with the corresponding technological stakes, the reactors specifications and advantages are detailed. (A.L.B.)

  17. Ship construction and welding

    CERN Document Server

    Mandal, Nisith R

    2017-01-01

    This book addresses various aspects of ship construction, from ship types and construction materials, to welding technologies and accuracy control. The contents of the book are logically organized and divided into twenty-one chapters. The book covers structural arrangement with longitudinal and transverse framing systems based on the service load, and explains basic structural elements like hatch side girders, hatch end beams, stringers, etc. along with structural subassemblies like floors, bulkheads, inner bottom, decks and shells. It presents in detail double bottom construction, wing tanks & duct keels, fore & aft end structures, etc., together with necessary illustrations. The midship sections of various ship types are introduced, together with structural continuity and alignment in ship structures. With regard to construction materials, the book discusses steel, aluminum alloys and fiber reinforced composites. Various methods of steel material preparation are discussed, and plate cutting and form...

  18. Nuclear ship accidents

    International Nuclear Information System (INIS)

    Oelgaard, P.L.

    1993-05-01

    In this report available information on 28 nuclear ship accident and incidents is considered. Of these 5 deals with U.S. ships and 23 with USSR ships. The ships are in almost all cases nuclear submarines. Only events that involve the nuclear propulsion plants, radiation exposures, fires/explosions and sea water leaks into the submarines are considered. Comments are made on each of the events, and at the end of the report an attempt is made to point out the weaknesses of the submarine designs which have resulted in the accidents. It is emphasized that much of the available information is of a rather dubious nature. consequently some of the assessments made may not be correct. (au)

  19. Performance Monitoring of Ships

    DEFF Research Database (Denmark)

    Hansen, Søren Vinther

    is used as input to the system and by comparing model and ship behaviour, an index describing the ship’s performance is generated. The work in this thesis is based on data logged through the automation system on board a PostPanmax container ship where data have been logged through a year. A routine...... in the models have been identified. The models used in this work are based on empirical relations or based on regression analyses of model tests and full-scale trials. In order to achieve valid results the conditions where performance is estimated have to be inside the boundaries of the model. Filters have been......The purpose of the research project is to establish a reliable index in the performance evaluation of ships. During operation the ship will experience added resistance due to fouling of hull and propeller. The added resistance will lead to increased fuel consumption and thus increased emissions...

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

    NARCIS (Netherlands)

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

    2012-01-01

    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

  1. 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...

  2. 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

  3. Quantifying external focus of attention in sailing by means of action sport cameras

    NARCIS (Netherlands)

    Pluijms, Joost; Canal Bruland, R.; Hoozemans, M.J.M.; Beek, M.; Brocker, K.; Savelsbergh, G.J.P.

    2016-01-01

    The aim of the current study was twofold: (1) to validate the use of action sport cameras for quantifying focus of visual attention in sailing and (2) to apply this method to examine whether an external focus of attention is associated with better performance in upwind sailing. To test the validity

  4. 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.

  5. Images in pediatrics: the thymic sail sign and thymic wave sign.

    Science.gov (United States)

    Alves, Nuno D; Sousa, Marta

    2013-01-01

    The authors present a radiographic image portraying the "thymic sail sign" and the "thymic wave sign," both normal findings in infant radiographs and present a short description of these signs. These are distinguished from pathologic findings such as the "spinnaker-sail sign" in pneumomediastinum.

  6. A System for Individualizing Instruction. Practical Answers to U-SAIL Implementation Questions. Monograph No. 4.

    Science.gov (United States)

    Utah System Approach to Individualized Learning Project.

    The U-SAIL system is a practical approach to individualization of instruction in which a problem-solving process is employed to install a program in logical sequential phases. U-SAIL is a nationally validated, successfully replicated, cost-feasible system for individualization of instruction which can be implemented in a variety of settings with…

  7. Enhancement of Presence in a Virtual Sailing Environment through Localized Wind Simulation

    NARCIS (Netherlands)

    Verlinden, J.C.; Mulder, F.A.; Vergeest, J.S.; De Jonge, A.; Krutiy, D.; Nagy, Z.; Logeman, B.J.; Schouten, P.

    2013-01-01

    In the context of sailing, wind plays an important role. However, there is little knowledge on how wind influences presence – the sense of “being there” - while immersed in a virtual setting. This article explores several wind parameters and presents a wind array to explore presence in a sail

  8. Distributed propulsion for ships

    OpenAIRE

    Nylund, Vilde

    2017-01-01

    It is anticipated that using distributed electric propulsion (DEP) on conventional ships will increase the total propulsive efficiency. This is mainly due to two reasons; firstly, because the total propeller disk area can be increased. Secondly, because each propeller can be optimised for the local wake where it is operating. In this work, the benefits of using DEP has been investigated for a 14 000 TEU container ship. Based on a literary study of the present state of propeller modelling ...

  9. SHIPPING REQUESTS ON EDH

    CERN Multimedia

    Logistics Group

    2001-01-01

    Users are informed that as from 1 September 2001 all Shipping Requests must be made on EDH using the appropriate electronic form. The submission of user requests directly into EDH will help rationalise the activities of the Shipping Service (Import & Export), with requests being automatically forwarded to hierarchical supervisors thereby improving the processing speed and facilitating the follow-up. Thank you for your collaboration.

  10. Plastic Pollution from Ships

    OpenAIRE

    Čulin, Jelena; Bielić, Toni

    2016-01-01

    The environmental impact of shipping on marine environment includes discharge of garbage. Plastic litter is of particular concern due to abundance, resistance to degradation and detrimental effect on marine biota. According to recently published studies, a further research is required to assess human health risk. Monitoring data indicate that despite banning plastic disposal at sea, shipping is still a source of plastic pollution. Some of the measures to combat the problem are discussed.

  11. On the Global Ship Hull Bending Energy in Ship Collisions

    DEFF Research Database (Denmark)

    Pedersen, Preben Terndrup; Li, Y.

    2004-01-01

    During ship collisions part of the kinetic energy of the involved vessels prior to contact is absorbed as energy dissipated by crushing of the hull structures, by friction and by elastic energy. The purpose of this report is to present an estimate of the elastic energy that can be stored in elastic...... hull vibrations during a ship collision. When a ship side is strengthened in order to improve the crashworthiness it has been argued in the scientific literature that a non trivial part of the energy released for structural deformation during the collision can be absorbed as elastic energy in global...... ship hull vibrations, such that with strong ship sides less energy has to be spent in crushing of the striking ship bow and/or the struck ship side. In normal ship-ship collision analyses both the striking and struck ship are usually considered as rigid bodies where structural crushing is confined...

  12. Outer Dynamics of Ship Collisions

    DEFF Research Database (Denmark)

    Pedersen, Preben Terndrup

    1996-01-01

    The purpose is to present analysis procedures for the motion of ships during ship-ship collisions and for ship collisions with offshore structures. The aim is to estimate that part of the lost kinetic energy which will have to be absorbed by rupture and plastic damage of the colliding structures....

  13. Recent situations around nuclear ships

    International Nuclear Information System (INIS)

    Mizuno, Hiroshi

    1978-01-01

    The philosophy when the safety standard for nuclear ships is drawn up and the international rules specifically for nuclear ships are summarized. As for the safety standard for nuclear ships, the safety requirements for ordinary ships, for the ships transporting nuclear reactors, for ordinary nuclear reactors, and for the reactors moving around the seas must be included. As for the international rules for nuclear ships, there are chapter 8 ''Nuclear ships'' in the International Convention on the Safety of Life at Sea, 1960 and 1974, and Safety Consideration in the Use of Ports and Approaches by Nuclear Merchant Ships. Also there are national rules and standards in Japan and foreign countries. One of the means to explore the practicality of nuclear ships is the investigation of the economy. At this time, the social merits and demerits of nuclear ships must be compared with conventional ships by taking total expenses into account without omission. When oil is depleted, the age of nuclear ships will not necessarily begin, and the will be still some competitors. The investigations concerning the economy of nuclear ships have been carried out in various countries. The present state of the development of nuclear ships in Japan and foreign countries is explained. Many conferences and symposia have been held concerning nuclear ships, and those held recently are enumerated. The realization of nuclear ship age cannot be anticipated from existing papers and shipbuilding projects. (Kako, I.)

  14. Outer Dynamics of Ship Collisions

    DEFF Research Database (Denmark)

    Pedersen, Preben Terndrup

    1996-01-01

    The purpose of these notes is to present analysis procedures for the motion of ships during ship-ship collisions and for ship collisons with offshore structures. The aim is to estimate that part of the lost kinetic energy which will have to be absorbed by rupture and plastic damage of the colliding...

  15. 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.

  16. In-Space Propulsion (ISP) Solar Sail Propulsion Technology Development

    Science.gov (United States)

    Montgomery, Edward E., IV

    2004-01-01

    An overview of the rationale and content for Solar Sail Propulsion (SSP), the on-going project to advance solar technology from technology readiness level 3 to 6 will be provided. A descriptive summary of the major and minor component efforts underway will include identification of the technology providers and a listing of anticipated products Recent important results from major system ground demonstrators will be provided. Finally, a current status of all activities will provided along with the most recent roadmap for the SSP technology development program.

  17. Monitoring shipping emissions in the German Bight using MAX-DOAS measurements

    Science.gov (United States)

    Seyler, André; Wittrock, Folkard; Kattner, Lisa; Mathieu-Üffing, Barbara; Peters, Enno; Richter, Andreas; Schmolke, Stefan; Burrows, John P.

    2017-04-01

    Shipping is generally the most energy efficient transportation mode, but, at the same time, it accounts for four fifths of the worldwide total merchandise trade volume. As a result, shipping contributes a significant part to the emissions from the transportation sector. The majority of shipping emissions occurs within 400 km of land, impacting on air pollution in coastal areas and harbor towns. The North Sea has one of the highest ship densities in the world and the vast majority of ships heading for the port of Hamburg sail through the German Bight and into the river Elbe. A three-year time series of ground-based MAX-DOAS measurements of NO2 and SO2 on the island Neuwerk in the German Bight has been analyzed for contributions from shipping emissions. Measurements of individual ship plumes as well as of background pollution are possible from this location, which is 6-7 kilometers away from the main shipping lane towards the harbor of Hamburg. More than 2000 individual ship plumes have been identified in the data and analyzed for the emission ratio of SO2 to NO2, yielding an average ratio of 0.3 for the years 2013/2014. Contributions of ships and land-based sources to air pollution levels in the German Bight have been estimated, showing that despite the vicinity to the shipping lane, the contribution of shipping sources to air pollution is only about 40%. Since January 2015, much lower fuel sulfur content limits of 0.1% (before: 1.0%) apply in the North and Baltic Sea Emission Control Area (ECA). Comparing MAX-DOAS measurements from 2015/2016 (new regulation) to 2013/2014 (old regulation), a large reduction in SO2/NO2 ratios in shipping emissions and a significant reduction (by a factor of eight) in ambient coastal SO2 levels have been observed. In addition to that, selected shipping emission measurements from other measurement sites and campaigns are presented. This study is part of the project MeSMarT (Measurements of Shipping emissions in the Marine Troposphere

  18. Accidents in nuclear ships

    Energy Technology Data Exchange (ETDEWEB)

    Oelgaard, P L [Risoe National Lab., Roskilde (Denmark); [Technical Univ. of Denmark, Lyngby (Denmark)

    1996-12-01

    This report starts with a discussion of the types of nuclear vessels accidents, in particular accidents which involve the nuclear propulsion systems. Next available information on 61 reported nuclear ship events in considered. Of these 6 deals with U.S. ships, 54 with USSR ships and 1 with a French ship. The ships are in almost all cases nuclear submarines. Only events that involve the sinking of vessels, the nuclear propulsion plants, radiation exposures, fires/explosions, sea-water leaks into the submarines and sinking of vessels are considered. For each event a summary of available information is presented, and comments are added. In some cases the available information is not credible, and these events are neglected. This reduces the number of events to 5 U.S. events, 35 USSR/Russian events and 1 French event. A comparison is made between the reported Soviet accidents and information available on dumped and damaged Soviet naval reactors. It seems possible to obtain good correlation between the two types of events. An analysis is made of the accident and estimates are made of the accident probabilities which are found to be of the order of 10{sup -3} per ship reactor years. It if finally pointed out that the consequences of nuclear ship accidents are fairly local and does in no way not approach the magnitude of the Chernobyl accident. It is emphasized that some of the information on which this report is based, may not be correct. Consequently some of the results of the assessments made may not be correct. (au).

  19. Accidents in nuclear ships

    International Nuclear Information System (INIS)

    Oelgaard, P.L.

    1996-12-01

    This report starts with a discussion of the types of nuclear vessels accidents, in particular accidents which involve the nuclear propulsion systems. Next available information on 61 reported nuclear ship events in considered. Of these 6 deals with U.S. ships, 54 with USSR ships and 1 with a French ship. The ships are in almost all cases nuclear submarines. Only events that involve the sinking of vessels, the nuclear propulsion plants, radiation exposures, fires/explosions, sea-water leaks into the submarines and sinking of vessels are considered. For each event a summary of available information is presented, and comments are added. In some cases the available information is not credible, and these events are neglected. This reduces the number of events to 5 U.S. events, 35 USSR/Russian events and 1 French event. A comparison is made between the reported Soviet accidents and information available on dumped and damaged Soviet naval reactors. It seems possible to obtain good correlation between the two types of events. An analysis is made of the accident and estimates are made of the accident probabilities which are found to be of the order of 10 -3 per ship reactor years. It if finally pointed out that the consequences of nuclear ship accidents are fairly local and does in no way not approach the magnitude of the Chernobyl accident. It is emphasized that some of the information on which this report is based, may not be correct. Consequently some of the results of the assessments made may not be correct. (au)

  20. Automated Planning for Liner Shipping Fleet Repositioning

    DEFF Research Database (Denmark)

    Tierney, Kevin; Jensen, Rune Møller; Kroer, Christian

    2012-01-01

    that are a function of their duration; for example, sailing slowly between two ports is cheaper than sailing quickly. Despite its great industrial importance, the LSFRP has received little attention in the literature. We show how the LSFRP can be solved sub-optimally using the planner POPF and optimally with a mixed...

  1. On the global ship hull bending energy in ship collisions

    DEFF Research Database (Denmark)

    Pedersen, Preben Terndrup; Li, Yujie

    2009-01-01

    During ship collisions part of the kinetic energy of the involved vessels immediately prior to contact is absorbed as energy dissipated by crushing of the hull structures, by friction and by elastic energy. The purpose of this report is to present an estimate of the elastic energy that can...... be stored in elastic hull vibrations during a ship collision. When a ship side is strengthened in order to improve the crashworthiness it has been argued in the scientific literature that a non-trivial part of the energy released for structural deformation during the collision can be absorbed as elastic...... energy in global ship hull vibrations, such that with strong ship sides less energy has to be spent in crushing of the striking ship bow and/or the struck ship side. In normal ship–ship collision analyses both the striking and struck ship are usually considered as rigid bodies where structural crushing...

  2. 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

  3. 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

  4. Sails: a new gypsum speleothem from Naica, Chihuahua, Mexico

    Directory of Open Access Journals (Sweden)

    Forti Paolo

    2007-01-01

    Full Text Available The caves of Naica (Chihuahua, Mexico are perhaps the most famous mine caves of the world due to the presence of giganticgypsum crystals. Nevertheless, very little research has been carried out on this karst area until now. A multidisciplinary investigationstarted in 2006 with the aim not only to define the genesis and the age of the Naica gypsum crystals, but also on other scientificaspects of these caves.This paper describes a completely new type of gypsum speleothem: the “sails”, observed only inside the Cueva de las Velas, one ofthe caves of the Naica system. This speleothem consists of extremely thin, elongated skeleton crystals that have grown epitaxiallyonly on the tips of the gypsum crystals pointing upward. The genesis of sails is strictly related to the environmental conditions setup inside the cave just after the artificial lowering of the groundwater by mine dewatering (less than 20 yr ago. In a few years sail speleothems will disappear entirely and therefore this study is fundamental to preserve at least the memory of them.

  5. 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.

  6. Ship operations report, 1973

    International Nuclear Information System (INIS)

    1973-01-01

    The NOAA Fleet Operations Report 1973 was developed to provide a summary of project accomplishments during calendar year 1973. The report was prepared from season, cruise and special reports submitted by ships of the fleet. Centralized management of the NOAA Fleet was finalized by changing the operational control of the National Marine Fisheries Service (NMFS) Ships DAVID STARR JORDAN (FRS 44), TOWNSEND CROMWELL (FRS 43) and MURRE II (FRV 63) from NMFS to the National Ocean Survey on July 1, 1973. Throughout the year, ships routinely collected and transmitted weather data. Similarly, as NOAA participants in the Integrated Global Ocean Station System (IGOSS) service program, XBT observations were taken and either radioed or submitted in log form via mail. In addition, particulate and radionuclide samples were taken in cooperation with the Atomic Energy Commission, sediment samples were obtained for the Smithsonian Institution and observations were made of marine mammals

  7. Ship operations report, 1975

    International Nuclear Information System (INIS)

    1976-01-01

    The NOAA Ship Operations Report 1975 was developed to provide a summary of projects undertaken during calendar year 1975. The report was prepared from season, cruise and special reports submitted by ships of the fleet. This report is promulgated for inhouse dissemination in the National Oceanic and Atmospheric Administration, for collaborating and interested agencies, and for use by members of the scientific community. Throughout the year, ships routinely collected and transmitted weather data. Similarly, as NOAA participants in the Integrated Global Ocean Station System (IGOSS) service program, XBT observations were taken and either radioed or submitted in log form via mail. In addition, particulate and radionuclide samples were taken in cooperation with the Atomic Energy Commission, sediment samples were obtained for the Smithsonian Institution and observations were made of marine mammals

  8. Internationalisation Within Liner Shipping

    DEFF Research Database (Denmark)

    Prockl, Günter; Kinra, Aseem; Kotzab, Herbert

    2018-01-01

    , the degree of internationalisation, measured on the basis of sea-oriented operations, differs from that measured according to land-oriented front-end marketing and sales activities. The purpose of this study is to further examine the internationalisation patterns of shipping lines. An examination...... of the front-end activities and the structures of leading container-shipping companies is conducted. The sales office networks of the sector’s 20 largest companies worldwide (by twenty-foot equivalent unit capacity) are analysed as key indicators. The numbers of sales offices are measured by analysing...... the websites of the sample (20 companies), as well as annual reports and other publicly available data sources. The findings show that not all shipping companies are international, by virtue of the industry. While it is difficult to observe differences in the overall patterns of the sales networks at a macro...

  9. Tidal sails : an alternative to turbines for harvesting tidal current energy

    Energy Technology Data Exchange (ETDEWEB)

    Hanssen, J.E. [Tidal Sails, Haugesund (Norway)

    2008-07-01

    Tidal sail technology harnesses the energy of tidal streams in order to produce electricity. Tidal currents move the sails that are attached to wires that rotate generator wheels to produce electricity. The technology has a low impact on the surrounding environment and is simple to install. This presentation discussed the methods used to determine the influence of relative sail velocity and measure estimated energy output levels. The sails were recently tested at an on-grid tidal stream pilot in the Norwegian Arctic. A 300 kW turbine installed at the site demonstrated that the site was suitable for a full-scale development of 20 tripod-mounted 600 kW turbines placed at 50 m depth. It was estimated that the 10 strings of 1000 m length provided between 200 and 250 GWh per year. The sails have also been used at a high speed site in Washington state in the United States. The 25 m pilot plant was installed to verify site suitability and examine sail behaviour in real, high-flow currents. It is expected that the technology will be fully commercialized by 2011. Other pilot tests are being conducted to examine flow behaviour; mooring and flotation functionality; and launch and lift capabilities. Engineering work is ongoing to examine plant designs, variable sail spacing, and collaborations with key component suppliers. tabs., figs.

  10. SAIL: Summation-bAsed Incremental Learning for Information-Theoretic Text Clustering.

    Science.gov (United States)

    Cao, Jie; Wu, Zhiang; Wu, Junjie; Xiong, Hui

    2013-04-01

    Information-theoretic clustering aims to exploit information-theoretic measures as the clustering criteria. A common practice on this topic is the so-called Info-Kmeans, which performs K-means clustering with KL-divergence as the proximity function. While expert efforts on Info-Kmeans have shown promising results, a remaining challenge is to deal with high-dimensional sparse data such as text corpora. Indeed, it is possible that the centroids contain many zero-value features for high-dimensional text vectors, which leads to infinite KL-divergence values and creates a dilemma in assigning objects to centroids during the iteration process of Info-Kmeans. To meet this challenge, in this paper, we propose a Summation-bAsed Incremental Learning (SAIL) algorithm for Info-Kmeans clustering. Specifically, by using an equivalent objective function, SAIL replaces the computation of KL-divergence by the incremental computation of Shannon entropy. This can avoid the zero-feature dilemma caused by the use of KL-divergence. To improve the clustering quality, we further introduce the variable neighborhood search scheme and propose the V-SAIL algorithm, which is then accelerated by a multithreaded scheme in PV-SAIL. Our experimental results on various real-world text collections have shown that, with SAIL as a booster, the clustering performance of Info-Kmeans can be significantly improved. Also, V-SAIL and PV-SAIL indeed help improve the clustering quality at a lower cost of computation.

  11. Utilization of an H-reversal trajectory of a solar sail for asteroid deflection

    International Nuclear Information System (INIS)

    Gong Shengping; Li Junfeng; Zeng Xiangyuan

    2011-01-01

    Near Earth Asteroids have a possibility of impacting the Earth and always represent a threat. This paper proposes a way of changing the orbit of the asteroid to avoid an impact. A solar sail evolving in an H-reversal trajectory is utilized for asteroid deflection. Firstly, the dynamics of the solar sail and the characteristics of the H-reversal trajectory are analyzed. Then, the attitude of the solar sail is optimized to guide the sail to impact the target asteroid along an H-reversal trajectory. The impact velocity depends on two important parameters: the minimum solar distance along the trajectory and lightness number of the solar sail. A larger lightness number and a smaller solar distance lead to a higher impact velocity. Finally, the deflection capability of a solar sail impacting the asteroid along the H-reversal trajectory is discussed. The results show that a 10 kg solar sail with a lead-time of one year can move Apophis out of a 600-m keyhole area in 2029 to eliminate the possibility of its resonant return in 2036. (editor's recommendation)

  12. Scale-model Experiment of Magnetoplasma Sail for Future Deep Space Missions

    International Nuclear Information System (INIS)

    Funaki, Ikkoh; Yamakawa, Hiroshi; Ueno, Kazuma; Kimura, Toshiyuki; Ayabe, Tomohiro; Horisawa, Hideyuki

    2008-01-01

    When Magnetic sail (MagSail) spacecraft is operated in space, the supersonic solar wind plasma flow is blocked by an artificially produced magnetic cavity to accelerate the spacecraft in the direction leaving the Sun. To evaluate the momentum transferring process from the solar wind to the coil onboard the MagSail spacecraft, we arranged a laboratory experiment of MagSail spacecraft. Based on scaling considerations, a solenoidal coil was immersed into the plasma flow from a magnetoplasmadynamic arcjet in a quasi-steady mode of about 1 ms duration. In this setup, it is confirmed that a magnetic cavity, which is similar to that of the geomagnetic field, was formed around the coil to produce thrust in the ion Larmor scale interaction. Also, the controllability of magnetic cavity size by a plasma jet from inside the coil of MagSail is demonstrated, although the thrust characteristic of the MagSail with plasma jet, which is so called plasma sail, is to be clarified in our next step

  13. Shipping emissions in ports

    OpenAIRE

    Merk, Olaf

    2014-01-01

    Shipping emissions in ports are substantial, accounting for 18 million tonnes of CO2 emissions, 0.4 million tonnes of NOx, 0.2 million of SOx and 0.03 million tonnes of PM10 in 2011. Around 85% of emissions come from containerships and tankers. Containerships have short port stays, but high emissions during these stays. Most of CO2 emissions in ports from shipping are in Asia and Europe (58%), but this share is low compared to their share of port calls (70%). European ports have much less emi...

  14. A solar sail design for a mission to the near-interstellar medium

    International Nuclear Information System (INIS)

    Garner, Charles E.; Layman, William; Gavit, Sarah A.; Knowles, Timothy

    2000-01-01

    Mission concepts to several hundred AU are under study at NASA Marshall Space Flight Center (MSFC) and NASA Jet Propulsion Laboratory (JPL). In order to send a scientific probe beyond the heliopause in a reasonable length of time - no more than 15 yr and preferably 10 yr - the ΔV requirements are approximately 70 km/s. The preliminary results of these mission studies indicate that a solar sail can provide a cumulative ΔV of over 70 km/s to send a probe to a distance of 200 AU from the Sun in under 15 years. This is done by using photon pressure on the sail to shape the trajectory in the inner solar system so that a perihelion of 0.25 AU is achieved. This paper presents the results of a design study for a solar sail to achieve the performance requirements identified in an interstellar probe (ISP) mission study to the near-interstellar medium. The baseline solar sail design for this ISP mission assumes an areal density of 1g/m2 (including film and structure), and a diameter of ∼410 m with an 11-m-wide central opening. The sail will be used from 0.25 to 5 AU, where it will be jettisoned. The total spacecraft module mass propelled by the sail is ∼191 kg. The gores of the sail are folded together and wrapped around a small cylinder. Centripetal force is used for sail deployment. The spacecraft is moved off-center with booms for sail attitude control and thrust vector pointing

  15. Are nuclear ships environmentally safer than conventionally powered ships

    International Nuclear Information System (INIS)

    Bone, C.A.; Molgaard, C.A.; Helmkamp, J.C.; Golbeck, A.L.

    1988-01-01

    An epidemiologic analysis was conducted to determine if risk of hospitalization varied by age, ship type, or occupation between nuclear and conventional powered ship crews in the U.S. Navy. Study cohorts consisted of all male enlisted personnel who served exclusively aboard conventional or nuclear powered aircraft carriers and cruisers during the years 1975-1979; cases were those men hospitalized during this period (N = 48,242). Conventional ship personnel showed significantly elevated rates of injury and disease when compared to nuclear ship personnel. The largest relative risks by age occurred for conventional ship crewmen less than 30 years old. Seaman, logistics (supply), and healthcare personnel serving aboard conventional ships comprised the occupational groups exhibiting the highest hospitalization rate differentials. The results strongly suggest that nuclear ships provide a healthier, safer working and living environment than conventional ships

  16. 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.

  17. Flights of a spacecraft with a solar sail out of ecliptic plane

    Science.gov (United States)

    Polyakhova, Elena; Starkov, Vladimir; Stepenko, Nikolai

    2018-05-01

    Solar sailing is an unique form of spacecraft (SC) propulsion that uses the free and limitless supply of photons from the Sun. The investigation of near-the-Sun space properties is of the great scientific interest. It can be realized by help of solar sailing. We present the numerical simulation of several closed modelled trajectories of a spacecraft with a controlled solar sail to reach out of ecliptic plane, to flight over the Sun north and south poles and return to the Earth.

  18. Mechanics of Ship Grounding

    DEFF Research Database (Denmark)

    Pedersen, Preben Terndrup

    1996-01-01

    In these notes first a simplified mathematical model is presented for analysis of ship hull loading due to grounding on relatively hard and plane sand, clay or rock sea bottoms. In a second section a more rational calculation model is described for the sea bed soil reaction forces on the sea bott...

  19. SHIPPING OF RADIOACTIVE ITEMS

    CERN Multimedia

    TIS/RP Group

    2001-01-01

    The TIS-RP group informs users that shipping of small radioactive items is normally guaranteed within 24 hours from the time the material is handed in at the TIS-RP service. This time is imposed by the necessary procedures (identification of the radionuclides, determination of dose rate and massive objects require a longer procedure and will therefore take longer.

  20. Ship Roll Motion Control

    DEFF Research Database (Denmark)

    Perez, Tristan; Blanke, Mogens

    2010-01-01

    . This tutorial paper presents an account of the development of various ship roll motion control systems and the challenges associated with their design. The paper discusses how to assess performance, the applicability of dierent models, and control methods that have been applied in the past....

  1. Ship Roll Damping Control

    DEFF Research Database (Denmark)

    Perez, Tristan; Blanke, Mogens

    2012-01-01

    limitations and large variations of the spectral characteristics of wave-induced roll motion. This tutorial paper presents an account of the development of various ship roll motion control systems together with the challenges associated with their design. It discusses the assessment of performance...

  2. Options of ship discharge

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-05-15

    Environmental performance is a key design consideration for manufacturers of bulk handling machines, not least ship unloaders, with features being introduced to minimise dust and noise pollution. The article reports on developments in grab unloaders, slewing grabcranes and mobile grabcranes by manufacturers such as Konecrane, EMS-Tech, Liebherr-Werk Nenzing and Gottwald. 2 photos.

  3. Hydroelastic Vibrations of Ships

    DEFF Research Database (Denmark)

    Jensen, Jørgen Juncher; Folsø, Rasmus

    2002-01-01

    A formula for the necessary hull girder bending stiffness required to avoid serious springing vibrations is derived. The expression takes into account the zero crossing period of the waves, the ship speed and main dimensions. For whipping vibrations the probability of exceedance for the combined...

  4. Effect of the Northern Sea Route Opening to the Shipping Activities at Malacca Straits

    Directory of Open Access Journals (Sweden)

    N.S.F. Abdul Rahman

    2014-12-01

    Full Text Available The opening of the Northern Sea Route as an alternative route for transporting cargoes between the Far East and Europe seems highly acceptable by shipping companies due to the great saving in fuel consumption, bunker cost, operating cost, emissions and journey time. This situation will not only affect the maritime business activity in the Straits of Malacca but also, the Malaysian economy in different perspectives when the vessels sail via the Suez Canal and the Indian Ocean are expected to decrease. The objective of this study is to analyse the implication in the opening of the Northern Sea Route on Maritime Sector of the Malaysian economy by using PESTEL analysis. The main scope is focusing more on the Malacca Straits shipping activity by using a number of parameters that have been obtained from Port Klang and Port Klang Authority through a set of questionnaires and interview sessions with industrial experts.

  5. Ship-induced solitary Riemann waves of depression in Venice Lagoon

    International Nuclear Information System (INIS)

    Parnell, Kevin E.; Soomere, Tarmo; Zaggia, Luca; Rodin, Artem; Lorenzetti, Giuliano; Rapaglia, John; Scarpa, Gian Marco

    2015-01-01

    We demonstrate that ships of moderate size, sailing at low depth Froude numbers (0.37–0.5) in a navigation channel surrounded by shallow banks, produce depressions with depths up to 2.5 m. These depressions (Bernoulli wakes) propagate as long-living strongly nonlinear solitary Riemann waves of depression substantial distances into Venice Lagoon. They gradually become strongly asymmetric with the rear of the depression becoming extremely steep, similar to a bore. As they are dynamically similar, air pressure fluctuations moving over variable-depth coastal areas could generate meteorological tsunamis with a leading depression wave followed by a devastating bore-like feature. - Highlights: • Unprecedently deep long-living ship-induced waves of depression detected. • Such waves are generated in channels with side banks under low Froude numbers. • The propagation of these waves is replicated using Riemann waves. • Long-living waves of depression form bore-like features at rear slope

  6. Ship-induced solitary Riemann waves of depression in Venice Lagoon

    Energy Technology Data Exchange (ETDEWEB)

    Parnell, Kevin E. [College of Marine and Environmental Sciences and Centre for Tropical Environmental and Sustainability Sciences, James Cook University, Queensland 4811 (Australia); Institute of Cybernetics at Tallinn University of Technology, Akadeemia tee 21, 12618 Tallinn (Estonia); Soomere, Tarmo, E-mail: soomere@cs.ioc.ee [Institute of Cybernetics at Tallinn University of Technology, Akadeemia tee 21, 12618 Tallinn (Estonia); Estonian Academy of Sciences, Kohtu 6, 10130 Tallinn (Estonia); Zaggia, Luca [Institute of Marine Sciences, National Research Council, Castello 2737/F, 30122 Venice (Italy); Rodin, Artem [Institute of Cybernetics at Tallinn University of Technology, Akadeemia tee 21, 12618 Tallinn (Estonia); Lorenzetti, Giuliano [Institute of Marine Sciences, National Research Council, Castello 2737/F, 30122 Venice (Italy); Rapaglia, John [Sacred Heart University Department of Biology, 5151 Park Avenue, Fairfield, CT 06825 (United States); Scarpa, Gian Marco [Università Ca' Foscari, Dorsoduro 3246, 30123 Venice (Italy)

    2015-03-06

    We demonstrate that ships of moderate size, sailing at low depth Froude numbers (0.37–0.5) in a navigation channel surrounded by shallow banks, produce depressions with depths up to 2.5 m. These depressions (Bernoulli wakes) propagate as long-living strongly nonlinear solitary Riemann waves of depression substantial distances into Venice Lagoon. They gradually become strongly asymmetric with the rear of the depression becoming extremely steep, similar to a bore. As they are dynamically similar, air pressure fluctuations moving over variable-depth coastal areas could generate meteorological tsunamis with a leading depression wave followed by a devastating bore-like feature. - Highlights: • Unprecedently deep long-living ship-induced waves of depression detected. • Such waves are generated in channels with side banks under low Froude numbers. • The propagation of these waves is replicated using Riemann waves. • Long-living waves of depression form bore-like features at rear slope.

  7. Classification of Ship Routing and Scheduling Problems in Liner Shipping

    DEFF Research Database (Denmark)

    Kjeldsen, Karina Hjortshøj

    2011-01-01

    This article provides a classification scheme for ship routing and scheduling problems in liner shipping in line with the current and future operational conditions of the liner shipping industry. Based on the classification, the literature is divided into groups whose main characteristics...

  8. 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

  9. Wallops Ship Surveillance System

    Science.gov (United States)

    Smith, Donna C.

    2011-01-01

    Approved as a Wallops control center backup system, the Wallops Ship Surveillance Software is a day-of-launch risk analysis tool for spaceport activities. The system calculates impact probabilities and displays ship locations relative to boundary lines. It enables rapid analysis of possible flight paths to preclude the need to cancel launches and allow execution of launches in a timely manner. Its design is based on low-cost, large-customer- base elements including personal computers, the Windows operating system, C/C++ object-oriented software, and network interfaces. In conformance with the NASA software safety standard, the system is designed to ensure that it does not falsely report a safe-for-launch condition. To improve the current ship surveillance method, the system is designed to prevent delay of launch under a safe-for-launch condition. A single workstation is designated the controller of the official ship information and the official risk analysis. Copies of this information are shared with other networked workstations. The program design is divided into five subsystems areas: 1. Communication Link -- threads that control the networking of workstations; 2. Contact List -- a thread that controls a list of protected item (ocean vessel) information; 3. Hazard List -- threads that control a list of hazardous item (debris) information and associated risk calculation information; 4. Display -- threads that control operator inputs and screen display outputs; and 5. Archive -- a thread that controls archive file read and write access. Currently, most of the hazard list thread and parts of other threads are being reused as part of a new ship surveillance system, under the SureTrak project.

  10. Prevention of oil spill from shipping by modelling of dynamic risk.

    Science.gov (United States)

    Eide, Magnus S; Endresen, Oyvind; Breivik, Oyvind; Brude, Odd Willy; Ellingsen, Ingrid H; Røang, Kjell; Hauge, Jarle; Brett, Per Olaf

    2007-10-01

    This paper presents a new dynamic environmental risk model, with intended use within a new, dynamical approach for risk based ship traffic prioritisation. The philosophy behind this newly developed approach is that shipping risk can be reduced by directing efforts towards ships and areas that have been identified as high priority (high risk), prior to a potential accident. The risk model proposed in this paper separates itself from previous models by drawing on available information on dynamic factors and by focusing on the ship's surroundings. The model estimates the environmental risk of drift grounding accidents for oil tankers in real time and in forecast mode, combining the probability of grounding with oil spill impact on the coastline. Results show that the inherent dynamic risk introduced by an oil tanker sailing along the North Norwegian coast depends, not surprisingly, significantly upon wind and ocean currents, as well as tug position and cargo oil type. Results of this study indicate that the risk model is well suited for real time risk assessment, and effectively separates low risk and high risk situations. The model is well suited as a tool to prioritise oil tankers and coastal segments. This enables dynamic risk based positioning of tugs, using both real-time and projected risk, for effective support in case of a drifting ship situation.

  11. Added masses of ship structures

    CERN Document Server

    Korotkin, Alexandr I

    2008-01-01

    This essentially self-contained reference book contains data on added masses of ships and various ship and marine engineering structures. Theoretical and experimental methods for determining added masses of these objects are described.

  12. Ship Observations - VOS and Navy

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Combination of Voluntary Observing Ship (VOS) and US Navy Ship weather observations. Obs generally taken 2-4 times daily at 00, 06, 12, and 18z.

  13. Lessons for Interstellar Travel from the Guidance and Control Design of the Near Earth Asteroid Scout Solar Sail Mission

    Science.gov (United States)

    Diedrich, Benjamin; Heaton, Andrew

    2017-01-01

    NASA is developing the Near Earth Asteroid (NEA) Scout mission that will use a solar sail to travel to an asteroid where it will perform a slow flyby to acquire science imagery. A guidance and control system was developed to meet the science and trajectory requirements. The NEA Scout design process can be applied to an interstellar or precursor mission that uses a beam propelled sail. The scientific objectives are met by accurately targeting the destination trajectory position and velocity. The destination is targeted by understanding the force on the sail from the beam (or sunlight in the case of NEA Scout) over the duration of the thrust maneuver. The propulsive maneuver is maintained by accurate understanding of the torque on the sail, which is a function of sail shape, optical properties, and mass properties, all of which apply to NEA Scout and beam propelled sails. NEA Scout uses active control of the sail attitude while trimming the solar torque, which could be used on a beamed propulsion sail if necessary. The biggest difference is that NEA Scout can correct for uncertainties in sail thrust modeling, spacecraft orbit, and target orbit throughout the flight to the target, while beamed propulsion needs accurate operation for the short duration of the beamed propulsion maneuver, making accurate understanding of the sail thrust and orbits much more critical.

  14. Lessons for Interstellar Travel from the G&C Design of the NEA Scout Solar Sail Mission

    Science.gov (United States)

    Heaton, Andrew; Diedrich, Benjamin

    2017-01-01

    NASA is developing the Near Earth Asteroid (NEA) Scout mission that will use a solar sail to travel to an asteroid where it will perform a slow flyby to acquire science imagery. A guidance and control system was developed to meet the science and trajectory requirements. The NEA Scout design process can be applied to an interstellar or precursor mission that uses a beam-propelled sail. The scientific objectives are met by accurately targeting the destination trajectory position and velocity. The destination is targeted by understanding the force on the sail from the beam (or sunlight in the case of NEA Scout) over the duration of the thrust maneuver. The propulsive maneuver is maintained by accurate understanding of the torque on the sail, which is a function of sail shape, optical properties, and mass properties, all of which apply to NEA Scout and beam propelled sails. NEA Scout uses active control of the sail attitude while trimming the solar torque, which could be used on a beamed propulsion sail if necessary. The biggest difference is that NEA Scout can correct for uncertainties in sail thrust modeling, spacecraft orbit, and target orbit throughout the flight to the target, while beamed propulsion needs accurate operation for the short duration of the beamed propulsion maneuver, making accurate understanding of the sail thrust and orbits much more critical.

  15. Trends of shipping markets development

    Directory of Open Access Journals (Sweden)

    Tomasz Nowosielski

    2012-06-01

    Full Text Available Shipping markets are dependent on international trade transactions that generate transport needs. These needs can dynamically change depending on global natural resources and commodity markets situation. The changes affecting shipping markets can also be caused by changes to the existing cargo flows and by establishing new ones in different geographies. It is anticipated that in the future shipping markets will change, visible by a decline in shipping in North America and Europe and an increase in Asia.

  16. Attitude Operation Results of Solar Sail Demonstrator IKAROS

    Science.gov (United States)

    Saiki, Takanao; Tsuda, Yuichi; Funase, Ryu; Mimasu, Yuya; Shirasawa, Yoji; Ikaros Demonstration Team,

    This paper shows the attitude operation results of Japanese interplanetary solar sail demonstration spacecraft IKAROS. IKAROS was launched on 21 May 2010(JST) aboard an H-IIA rocket, together with the AKATSUKI Venus climate orbiter. As IKAROS is the secondary payload, the development cost and period were restricted and the onboard attitude system is very simple. This paper introduces the attitude determination and control system. And as IKAROS is spin type spacecraft and it has the large membrane, the attitude control is not easy and it is very important to determine the long-term attitude plan in advance. This paper also shows the outline of the IKAROS attitude operation plan and its operation results.

  17. Design of the De-Orbit Sail Boom Deployment Unit

    Science.gov (United States)

    Meyer, Sebastian; Hillebrandt, Martin; Straubel, Marco; Huhne, Christian

    2014-06-01

    The design of the De-Orbit Sail boom deployment unit is strongly driven by volume constraints, which are given by the cubesat container. Four CFRP (carbon fiber reinforced polymer) booms [4] with a cross-sectional shape of a double-omega and a length of 3.6 m are reeled on one spool in the center of the unit. The deployment of the four booms are controlled by an electric motor, which acts on the boom spool. Due to the volume limitation caused by the dimensions of the cubesat deployer the deployment unit has little room for the mechanisms components. With the aim to achieve a robust design, the deployment concept of the unit has greatly changed during the development process. The history of the design as well as the mechanisms are described. Additionally the results of the flight model testing are presented.

  18. High cost for drilling ships

    International Nuclear Information System (INIS)

    Hooghiemstra, J.

    2007-01-01

    Prices for the rent of a drilling ship are very high. Per day the rent is 1% of the price for building such a ship, and those prices have risen as well. Still, it is attractive for oil companies to rent a drilling ship [nl

  19. Solar Sail Models and Test Measurements Correspondence for Validation Requirements Definition

    Science.gov (United States)

    Ewing, Anthony; Adams, Charles

    2004-01-01

    Solar sails are being developed as a mission-enabling technology in support of future NASA science missions. Current efforts have advanced solar sail technology sufficient to justify a flight validation program. A primary objective of this activity is to test and validate solar sail models that are currently under development so that they may be used with confidence in future science mission development (e.g., scalable to larger sails). Both system and model validation requirements must be defined early in the program to guide design cycles and to ensure that relevant and sufficient test data will be obtained to conduct model validation to the level required. A process of model identification, model input/output documentation, model sensitivity analyses, and test measurement correspondence is required so that decisions can be made to satisfy validation requirements within program constraints.

  20. An investigation of headsail/mainsail interaction in a sailing yacht

    International Nuclear Information System (INIS)

    Neumann, P.M.; Johannes, R.A.; Keffer, J.F.

    1985-01-01

    In a previous paper, the separation zone immediately behind the mast for a main-sail/genoa configuration was analysed for a number of cross-sectional shapes and angles of attack to determine the effect upon the windward performance of the rig. The study was carried out with and without the presence of the overlapping genoa in order to isolate the effects of the two sails. Lift and drag were determined for the mast/main-sail combination using rows of static pressure taps. From this the zones of separation at the mast on the leeward and windward were inferred. These data were supported independently from hot-wire traverses along the sail in the separation regions. As well the lift/drag ratio of the mast/mainsail was determined as a function of the sheeting angles of both the main and the genoa. A quantitative assessment of this ratio, provided the optimum sheeting angles for this configuration. (author)

  1. 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.

  2. Fixed-axis electric sail deployment dynamics analysis using hub-mounted momentum control

    Science.gov (United States)

    Fulton, JoAnna; Schaub, Hanspeter

    2018-03-01

    The deployment dynamics of a spin stabilized electric sail (E-sail) with a hub-mounted control actuator are investigated. Both radial and tangential deployment mechanisms are considered to take the electric sail from a post-launch stowed configuration to a fully deployed configuration. The tangential configuration assumes the multi-kilometer tethers are wound up on the exterior of the spacecraft hub, similar to yo-yo despinner configurations. The deployment speed is controlled through the hub rate. The radial deployment configuration assumes each tether is on its own spool. Here both the hub and spool rate are control variables. The sensitivity of the deployment behavior to E-sail length, maximum rate and tension parameters is investigated. A constant hub rate deployment is compared to a time varying hub rate that maintains a constant tether tension condition. The deployment time can be reduced by a factor of 2 or more by using a tension controlled deployment configuration.

  3. Economic feasibility of sail power devices on Great Lakes bulk carriers

    Energy Technology Data Exchange (ETDEWEB)

    1982-03-24

    Progress is reported in a project to determine whether retro-fitting existing Great Lakes bulk carriers with auxiliary sail powering devices is economically feasible. The approach being used is to apply known technology both in terms of sail devices and calculation methods to determine the amount of fuel that can be saved and the probable cost of the sail device. Progress includes the identification and collection of data needed to determine the state of the art as well as to model the problem. Several sail powering devices were compared and an unstayed cat rig was chosen for further analysis and its performance characteristics were incorporated into a computer model, which is flow charted. (LEW)

  4. The SAIL databank: linking multiple health and social care datasets

    Directory of Open Access Journals (Sweden)

    Ford David V

    2009-01-01

    Full Text Available Abstract Background Vast amounts of data are collected about patients and service users in the course of health and social care service delivery. Electronic data systems for patient records have the potential to revolutionise service delivery and research. But in order to achieve this, it is essential that the ability to link the data at the individual record level be retained whilst adhering to the principles of information governance. The SAIL (Secure Anonymised Information Linkage databank has been established using disparate datasets, and over 500 million records from multiple health and social care service providers have been loaded to date, with further growth in progress. Methods Having established the infrastructure of the databank, the aim of this work was to develop and implement an accurate matching process to enable the assignment of a unique Anonymous Linking Field (ALF to person-based records to make the databank ready for record-linkage research studies. An SQL-based matching algorithm (MACRAL, Matching Algorithm for Consistent Results in Anonymised Linkage was developed for this purpose. Firstly the suitability of using a valid NHS number as the basis of a unique identifier was assessed using MACRAL. Secondly, MACRAL was applied in turn to match primary care, secondary care and social services datasets to the NHS Administrative Register (NHSAR, to assess the efficacy of this process, and the optimum matching technique. Results The validation of using the NHS number yielded specificity values > 99.8% and sensitivity values > 94.6% using probabilistic record linkage (PRL at the 50% threshold, and error rates were Conclusion With the infrastructure that has been put in place, the reliable matching process that has been developed enables an ALF to be consistently allocated to records in the databank. The SAIL databank represents a research-ready platform for record-linkage studies.

  5. The SAIL databank: linking multiple health and social care datasets.

    Science.gov (United States)

    Lyons, Ronan A; Jones, Kerina H; John, Gareth; Brooks, Caroline J; Verplancke, Jean-Philippe; Ford, David V; Brown, Ginevra; Leake, Ken

    2009-01-16

    Vast amounts of data are collected about patients and service users in the course of health and social care service delivery. Electronic data systems for patient records have the potential to revolutionise service delivery and research. But in order to achieve this, it is essential that the ability to link the data at the individual record level be retained whilst adhering to the principles of information governance. The SAIL (Secure Anonymised Information Linkage) databank has been established using disparate datasets, and over 500 million records from multiple health and social care service providers have been loaded to date, with further growth in progress. Having established the infrastructure of the databank, the aim of this work was to develop and implement an accurate matching process to enable the assignment of a unique Anonymous Linking Field (ALF) to person-based records to make the databank ready for record-linkage research studies. An SQL-based matching algorithm (MACRAL, Matching Algorithm for Consistent Results in Anonymised Linkage) was developed for this purpose. Firstly the suitability of using a valid NHS number as the basis of a unique identifier was assessed using MACRAL. Secondly, MACRAL was applied in turn to match primary care, secondary care and social services datasets to the NHS Administrative Register (NHSAR), to assess the efficacy of this process, and the optimum matching technique. The validation of using the NHS number yielded specificity values > 99.8% and sensitivity values > 94.6% using probabilistic record linkage (PRL) at the 50% threshold, and error rates were SAIL databank represents a research-ready platform for record-linkage studies.

  6. Towards Real Time Simulation of Ship-Ship Interaction

    DEFF Research Database (Denmark)

    Lindberg, Ole; Bingham, Harry B.; Engsig-Karup, Allan Peter

    2012-01-01

    We present recent and preliminary work directed towards the development of a simplified, physics-based model for improved simulation of ship-ship interaction that can be used for both analysis and real-time computing (i.e. with real-time constraints due to visualization). The goal is to implement...... accurate (realistic) and much faster ship-wave and ship-ship simulations than are currently possible. The coupling of simulation with visualization should improve the visual experience such that it can be perceived as more realistic in training. Today the state-of-art in real-time ship-ship interaction...... is for efficiency reasons and time-constraints in visualization based on model experiments in towing tanks and precomputed force tables. We anticipate that the fast, and highly parallel, algorithm described by Engsig-Karup et al. [2011] for execution on affordable modern high-throughput Graphics Processing Units...

  7. Bibliography of the SAIL Panama Canal Zone Project 2008 : a selected bibliography.

    OpenAIRE

    DeHart, Liz

    2009-01-01

    During the 18th Annual 2008 SAIL meeting at the Smithsonian Tropical Research Institute in Panama, Vielka Chang-Yau, librarian, mentioned the need to digitize and make available through the Aquatic Commons some of the early documents related to the U.S. biological survey of Panama from 1910 to 1912. With the assistance of SAIL, a regional marine librarian’s group, a digital project developed and this select bibliography represents the sources used for the project. It will assist research...

  8. A novel experimental mechanics method for measuring the light pressure acting on a solar sail membrane

    Science.gov (United States)

    Shi, Aiming; Jiang, Li; Dowell, Earl H.; Qin, Zhixuan

    2017-02-01

    Solar sail is a high potential `sailing craft' for interstellar exploration. The area of the first flight solar sail demonstrator named "IKAROS" is 200 square meters. Future interplanetary missions will require solar sails at least on the order of 10000 square meters (or larger). Due to the limitation of ground facilities, the size of experimental sample should not be large. Furthermore the ground experiments have to be conducted in gravitational field, so the gravity effect must be considered in a ground test. To obtain insight into the solar sail membrane dynamics, a key membrane flutter (or limit cycle oscillations) experiment with light forces acting on it must be done. But one big challenge is calibrating such a tiny light force by as a function of the input power. In this paper, a gravity-based measuring method for light pressure acting on membrane is presented. To explain the experimental principle, an ideal example of a laser beam with expanders and a metal film is studied. Based on calculations, this experimental mechanics method for calibrating light pressure with an accuracy of 0.01 micro-Newton may be realized by making the light force balance the gravity force on the metal films. This gravity-based measuring method could not only be applied to study the dynamics characteristics of solar sail membrane structure with different light forces, but could also be used to determine more accurate light forces/loads acting on solar sail films and hence to enhance the determination of the mechanical properties of the solar sail membrane structure.

  9. Prediction of velocity and attitude of a yacht sailing upwind by computational fluid dynamics

    OpenAIRE

    Lee, Heebum; Park, Mi Yeon; Park, Sunho; Rhee, Shin Hyung

    2016-01-01

    One of the most important factors in sailing yacht design is accurate velocity prediction. Velocity prediction programs (VPP's) are widely used to predict velocity of sailing yachts. VPP's, which are primarily based on experimental data and experience of long years, however suffer limitations when applied in realistic conditions. Thus, in the present study, a high fidelity velocity prediction method using computational fluid dynamics (CFD) was proposed. Using the developed method, velocity an...

  10. 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.

  11. Developing a business plan for a company in Finland owned by foreigners. Case: Prime Sails Ltd

    OpenAIRE

    Honkonen-Kulagina, Alina Linda

    2012-01-01

    To establish a new company is challenging for any businessman or businesswomen. Starting up a company in a foreign country is twice is hard. The purpose of the thesis is to examine the factors that affect the success of a company newly-established by immigrants. These include such areas as good business plan, market research, cultural knowledge and awareness of the legislative environment. The case study focuses on the company Prime Sails Ltd, which is a supplier of sails. The main ob...

  12. EMP coupling to ships

    International Nuclear Information System (INIS)

    Deadrick, F.J.; Cabayan, H.S.; Kunz, K.F.; Bevensee, R.M.; Martin, L.C.; Egbert, R.W.

    1980-01-01

    Scale-model tests were conducted to establish the adequacy and limitations of model measurements as tools for predicting electromagnetic pulse (EMP) coupling voltages and currents to the critical antennas, cables, and metallic structures on ships. The scale-model predictions are compared with the results of the full-scale EMP simulation test of the Canadian ASW ship, HMCS Huron. (The EMP coupling predictions in this report were made without prior knowledge of the results of the data from the HMCS Huron tests.) This report establishes that the scale-model tests in conjunction with the data base from EMP coupling modules provides the necessary information for source model development and permits effective, low-cost study of particular system configurations. 184 figures, 9 tables

  13. Calculation of Flows Over Underwater Bodies with Hull, Sail and Appendages

    International Nuclear Information System (INIS)

    Shoab, M.; Ayub, M.; Bilal, S.; Zahir, S.; Khan, M.A.

    2004-01-01

    A comprehensive study has been made for the hydrodynamic analysis of the submarine DARPA 2. The analysis was first performed for hull, then hull with sail on top and then for the complete submarine including hull, sail and appendages. A comparison of tangential velocity and pressure distribution for hull is accomplished using CFD flow solvers and published data. Further, the pressure distribution over the hull with sail is also analyzed. Finally, pressure distribution, forces and moments were calculated over the complete submarine including hull, sail and appendages. Comparison 01 pressure distribution and tangential velocity for the hull show a good agreement with published data. Pressure coefficient comparison for the hull with sail shows the good CFD-CFD agreement. Comparison of Normal force and pitching moment of complete submarine having hull, sail and appendages shows a reasonable agreement with the experimental results of DARPA 2. Both quantitative and qualitative analysis of the complete submarine estimates the required design force and moment at different angles of attack and also demonstrate the flow visualization. (author)

  14. A novel antibody–drug conjugate targeting SAIL for the treatment of hematologic malignancies

    International Nuclear Information System (INIS)

    Kim, S Y; Theunissen, J-W; Balibalos, J; Liao-Chan, S; Babcock, M C

    2015-01-01

    Although several new therapeutic approaches have improved outcomes in the treatment of hematologic malignancies, unmet need persists in acute myeloid leukemia (AML), multiple myeloma (MM) and non-Hodgkin's lymphoma. Here we describe the proteomic identification of a novel cancer target, SAIL (Surface Antigen In Leukemia), whose expression is observed in AML, MM, chronic lymphocytic leukemia (CLL), diffuse large B-cell lymphoma (DLBCL) and follicular lymphoma (FL). While SAIL is widely expressed in CLL, AML, MM, DLBCL and FL patient samples, expression in cancer cell lines is mostly limited to cells of AML origin. We evaluated the antitumor activity of anti-SAIL monoclonal antibodies, 7-1C and 67-7A, conjugated to monomethyl auristatin F. Following internalization, anti-SAIL antibody–drug conjugates (ADCs) exhibited subnanomolar IC 50 values against AML cell lines in vitro. In pharmacology studies employing AML cell line xenografts, anti-SAIL ADCs resulted in significant tumor growth inhibition. The restricted expression profile of this target in normal tissues, the high prevalence in different types of hematologic cancers and the observed preclinical activity support the clinical development of SAIL-targeted ADCs

  15. Aerodynamics of yacht sails: viscous flow features and surface pressure distributions

    Science.gov (United States)

    Viola, Ignazio Maria

    2014-11-01

    The present paper presents the first Detached Eddy Simulation (DES) on a yacht sails. Wind tunnel experiments on a 1:15th model-scale sailing yacht with an asymmetric spinnaker (fore sail) and a mainsails (aft sail) were modelled using several time and grid resolutions. Also the Reynolds-average Navier-Stokes (RANS) equations were solved for comparison with DES. The computed forces and surface pressure distributions were compared with those measured with both flexible and rigid sails in the wind tunnel and good agreement was found. For the first time it was possible to recognise the coherent and steady nature of the leading edge vortex that develops on the leeward side of the asymmetric spinnaker and which significantly contributes to the overall drive force. The leading edge vortex increases in diameter from the foot to the head of the sail, where it becomes the tip vortex and convects downstream in the direction of the far field velocity. The tip vortex from the head of the mainsail rolls around the one of the spinnaker. The spanwise twist of the spinnaker leads to a mid-span helicoidal vortex, which has never been reported by previous authors, with an horizontal axis and rotating in the same direction of the tip vortex.

  16. 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.

  17. A novel antibody-drug conjugate targeting SAIL for the treatment of hematologic malignancies.

    Science.gov (United States)

    Kim, S Y; Theunissen, J-W; Balibalos, J; Liao-Chan, S; Babcock, M C; Wong, T; Cairns, B; Gonzalez, D; van der Horst, E H; Perez, M; Levashova, Z; Chinn, L; D'Alessio, J A; Flory, M; Bermudez, A; Jackson, D Y; Ha, E; Monteon, J; Bruhns, M F; Chen, G; Migone, T-S

    2015-05-29

    Although several new therapeutic approaches have improved outcomes in the treatment of hematologic malignancies, unmet need persists in acute myeloid leukemia (AML), multiple myeloma (MM) and non-Hodgkin's lymphoma. Here we describe the proteomic identification of a novel cancer target, SAIL (Surface Antigen In Leukemia), whose expression is observed in AML, MM, chronic lymphocytic leukemia (CLL), diffuse large B-cell lymphoma (DLBCL) and follicular lymphoma (FL). While SAIL is widely expressed in CLL, AML, MM, DLBCL and FL patient samples, expression in cancer cell lines is mostly limited to cells of AML origin. We evaluated the antitumor activity of anti-SAIL monoclonal antibodies, 7-1C and 67-7A, conjugated to monomethyl auristatin F. Following internalization, anti-SAIL antibody-drug conjugates (ADCs) exhibited subnanomolar IC50 values against AML cell lines in vitro. In pharmacology studies employing AML cell line xenografts, anti-SAIL ADCs resulted in significant tumor growth inhibition. The restricted expression profile of this target in normal tissues, the high prevalence in different types of hematologic cancers and the observed preclinical activity support the clinical development of SAIL-targeted ADCs.

  18. A novel antibody–drug conjugate targeting SAIL for the treatment of hematologic malignancies

    Science.gov (United States)

    Kim, S Y; Theunissen, J-W; Balibalos, J; Liao-Chan, S; Babcock, M C; Wong, T; Cairns, B; Gonzalez, D; van der Horst, E H; Perez, M; Levashova, Z; Chinn, L; D‘Alessio, J A; Flory, M; Bermudez, A; Jackson, D Y; Ha, E; Monteon, J; Bruhns, M F; Chen, G; Migone, T-S

    2015-01-01

    Although several new therapeutic approaches have improved outcomes in the treatment of hematologic malignancies, unmet need persists in acute myeloid leukemia (AML), multiple myeloma (MM) and non-Hodgkin's lymphoma. Here we describe the proteomic identification of a novel cancer target, SAIL (Surface Antigen In Leukemia), whose expression is observed in AML, MM, chronic lymphocytic leukemia (CLL), diffuse large B-cell lymphoma (DLBCL) and follicular lymphoma (FL). While SAIL is widely expressed in CLL, AML, MM, DLBCL and FL patient samples, expression in cancer cell lines is mostly limited to cells of AML origin. We evaluated the antitumor activity of anti-SAIL monoclonal antibodies, 7-1C and 67-7A, conjugated to monomethyl auristatin F. Following internalization, anti-SAIL antibody–drug conjugates (ADCs) exhibited subnanomolar IC50 values against AML cell lines in vitro. In pharmacology studies employing AML cell line xenografts, anti-SAIL ADCs resulted in significant tumor growth inhibition. The restricted expression profile of this target in normal tissues, the high prevalence in different types of hematologic cancers and the observed preclinical activity support the clinical development of SAIL-targeted ADCs. PMID:26024286

  19. SHIPPING OF RADIOACTIVE ITEMS

    CERN Multimedia

    TIS/RP Group

    2001-01-01

    The TIS-RP group informs users that shipping of small radioactive items is normally guaranteed within 24 hours from the time the material is handed in at the TIS-RP service. This time is imposed by the necessary procedures (identification of the radionuclides, determination of dose rate, preparation of the package and related paperwork). Large and massive objects require a longer procedure and will therefore take longer.

  20. Ship and Shoot

    Science.gov (United States)

    Woods, Ron

    2012-01-01

    Ron Woods shared incredibly valuable insights gained during his 28 years at the Kennedy Space Center (KSC) packaging Flight Crew Equipment for shuttle and ISS missions. In particular, Woods shared anecdotes and photos from various processing events. The moral of these stories and the main focus of this discussion were the additional processing efforts and effects related to a "ship-and-shoot" philosophy toward flight hardware.

  1. Optimal load allocation of complex ship power plants

    International Nuclear Information System (INIS)

    Baldi, Francesco; Ahlgren, Fredrik; Melino, Francesco; Gabrielii, Cecilia; Andersson, Karin

    2016-01-01

    Highlights: • The optimal operation of the prime movers of hybrid ship power plants is addressed. • Both mechanical, electric and thermal power demand are considered. • The problem is modelled as a mixed integer-nonlinear programming problem. • Up to 3% savings can be achieved with hybrid power plants. • Including the thermal power demand improves the solution by up to 4%. - Abstract: In a world with increased pressure on reducing fuel consumption and carbon dioxide emissions, the cruise industry is growing in size and impact. In this context, further effort is required for improving the energy efficiency of cruise ship energy systems. In this paper, we propose a generic method for modelling the power plant of an isolated system with mechanical, electric and thermal power demands and for the optimal load allocation of the different components that are able to fulfil the demand. The optimisation problem is presented in the form of a mixed integer linear programming (MINLP) problem, where the number of engines and/or boilers running is represented by the integer variables, while their respective load is represented by the non-integer variables. The individual components are modelled using a combination of first-principle models and polynomial regressions, thus making the system nonlinear. The proposed method is applied to the load-allocation problem of a cruise ship sailing in the Baltic Sea, and used to compare the existing power plant with a hybrid propulsion plant. The results show the benefits brought by using the proposing method, which allow estimating the performance of the hybrid system (for which the load allocation is a non-trivial problem) while also including the contribution of the heat demand. This allows showing that, based on a reference round voyage, up to 3% savings could be achieved by installing the proposed system, compared to the existing one, and that a NPV of 11 kUSD could be achieved already 5 years after the installation of the

  2. Tourist ships on the Danube as an opportunity for export of meat and meat products

    Directory of Open Access Journals (Sweden)

    Tešanović Dragan

    2015-01-01

    Full Text Available Tourism development launches growth of other complementary industries. River tourism, as a special selective tourism form, experiences intensive development, with an importance for all the regions through which the Danube, as an integral part of the Rhine - Main - Danube waterway, flows. During cruising, the largest consumption is achieved on the ship itself, where meat and meat products are an integral element of every meal and represent the most expensive component of the dish. The task of this paper is to analyse the consumption of meat and meat products on six tourist ships run by to 'Grand Circle Corporation' in 2013, in order to point out the possibility of supplying them with meat and meat products from sources in the territory where the ships sail. The paper presents the current suppliers and manufacturers of meat and meat products in Republic of Serbia that could supply the company 'Grand Circle Cruise Line' and other tourist ships that cruise on the Danube. Also, the research indicates that the export of meat products from the Republic Serbia could have a significant effect on improving the agricultural conditions and food production through increased competition, assuming the Serbian manufacturers supply most of tourist ships and not only the six ships analysed in this paper. Research results, specifically, point out the possibility of increasing export of poultry and beef if the potential demand of each of the eight companies with their 54 ships which operate tourist cruises on the Danube is taken into account. The data have been systematized, analysed and presented statistically in tables and graphs.

  3. Analysis of a ship-to-ship collision

    International Nuclear Information System (INIS)

    Porter, V.L.; Ammerman, D.J.

    1996-01-01

    Sandia National Laboratories is involved in a safety assessment for the shipment of radioactive material by sea. One part of this study is investigation of the consequences of ship-to-ship collisions. This paper describes two sets of finite element analyses performed to assess the structural response of a small freighter and the loading imparted to radioactive material (RAM) packages during several postulated collision scenarios with another ship. The first series of analyses was performed to evaluate the amount of penetration of the freighter hull by a striking ship of various masses and initial velocities. Although these analyses included a representation of a single RAM package, the package was not impacted during the collision so forces on the package could not be computed. Therefore, a second series of analyses incorporating a representation of a row of seven packages was performed to ensure direct package impact by the striking ship. Average forces on a package were evaluated for several initial velocities and masses of the striking ship. In addition to. providing insight to ship and package response during a few postulated ship collisions scenarios, these analyses will be used to benchmark simpler ship collision models used in probabilistic risk assessment analyses

  4. Hospital Ship Replacement

    Science.gov (United States)

    2011-08-01

    serious contender. Although it is a proven hull design for stability, integrating the ability to quickly transfer patients aboard is challenging . The...Waste management afloat is a constant challenge for the Navy. It is even more so when designing a hospital ship. In addition to the typical waste...0.97 Optbrs: Corrmon rail fuellrijacllon,crude oil. Rated power generating sets 61:ili:ln()q;to~ 50Htl760rpm &.gne type -1801.\\ Vlc )l ~W.’/cyl SI;O k

  5. Nonlinear Container Ship Model for the Study of Parametric Roll Resonance

    Directory of Open Access Journals (Sweden)

    Christian Holden

    2007-10-01

    Full Text Available Parametric roll is a critical phenomenon for ships, whose onset may cause roll oscillations up to +-40 degrees, leading to very dangerous situations and possibly capsizing. Container ships have been shown to be particularly prone to parametric roll resonance when they are sailing in moderate to heavy head seas. A Matlab/Simulink parametric roll benchmark model for a large container ship has been implemented and validated against a wide set of experimental data. The model is a part of a Matlab/Simulink Toolbox (MSS, 2007. The benchmark implements a 3rd-order nonlinear model where the dynamics of roll is strongly coupled with the heave and pitch dynamics. The implemented model has shown good accuracy in predicting the container ship motions, both in the vertical plane and in the transversal one. Parametric roll has been reproduced for all the data sets in which it happened, and the model provides realistic results which are in good agreement with the model tank experiments.

  6. A Global Maritime Emissions Trading System. Design and Impacts on the Shipping Sector, Countries and Regions

    Energy Technology Data Exchange (ETDEWEB)

    Faber, J.; Markowska, A.; Eyring, V.; Cionni, I.; Selstad, E. Shipping / Emissions trading / Economy / Costs / Effects / Developing countries Publication number:

    2010-01-15

    This report designs a global cap-and-trade scheme for maritime transport and assesses its impacts on the shipping sector, regions and groups of countries. It shows that it is feasible to implement a cap-and-trade scheme for greenhouse gas emissions in the maritime transport sector. Such a scheme ensures that the environmental target is met, while allowing the sector to grow and ensuring that the target is met in the most cost-effective way. An emissions trading scheme would result in an increase in the costs of shipping of less than 10%, depending on the price of allowances. The increase in import values is likely to be less than 1% for most commodity groups, and the impact on consumer prices even lower. Using new data on emissions of ships sailing to regions and country groups, this report demonstrates that the additional costs of imports for most regions and country groups are estimated to be less than 0.2% of GDP, with a few exceptions. This report demonstrates that it is possible to compensate developing countries for the increased costs of imports by using approximately two thirds of the revenues of the auction. The remainder of the revenues can be used for other aims, such as R and D into fuel-efficiency of ships.

  7. 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).

  8. Ship Creek bioassessment investigations

    Energy Technology Data Exchange (ETDEWEB)

    Cushing, C.E.; Mueller, R.P.; Murphy, M.T.

    1995-06-01

    Pacific Northwest Laboratory (PNL) was asked by Elmendorf Air Force Base (EAFB) personnel to conduct a series of collections of macroinvertebrates and sediments from Ship Creek to (1) establish baseline data on these populations for reference in evaluating possible impacts from Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) activities at two operable units, (2) compare current population indices with those found by previous investigations in Ship Creek, and (3) determine baseline levels of concentrations of any contaminants in the sediments associated with the macroinvertebrates. A specific suite of indices established by the US Environmental Protection Agency (EPA) was requested for the macroinvertebrate analyses; these follow the Rapid Bioassessment Protocol developed by Plafkin et al. (1989) and will be described. Sediment sample analyses included a Microtox bioassay and chemical analysis for contaminants of concern. These analyses included, volatile organic compounds, total gasoline and diesel hydrocarbons (EPA method 8015, CA modified), total organic carbon, and an inductive-coupled plasma/mass spectrometry (ICP/MS) metals scan. Appendix A reports on the sediment analyses. The Work Plan is attached as Appendix B.

  9. ERDC Ship/Tow Simulator

    Data.gov (United States)

    Federal Laboratory Consortium — Performing Advanced Hydrodynamic ModelingEngineers and ship pilots can now overcome the challenges of evaluating navigation channel designs, modifications and safety...

  10. Assembly of Space CFRP Structures with Racing Sailing Boats Technology

    Science.gov (United States)

    Nieto, Jose; Yuste, Laura; Pipo, Alvaro; Santarsiero, Pablo; Bureo, Rafael

    2014-06-01

    Carbon Fiber Reinforced Plastic (CFRP) is commonly used in space applications to get structures with good mechanical performances and a reduced mass. Most of larger parts of spatial structures are already made of CFRP but the achieved weight saving may be jeopardized by the use of metallic brackets as joining elements. This paper describes the work carried out to study and evaluate ways of reducing weight and costs of the joints between structural elements commonly used in space applications.The main objective of this project is to adapt design solutions coming from the racing sailing boats technology to space applications: the use of out-of autoclave (OoA) cured CFRP joints. In addition to that other CFRP solution common in space business, 3D- RTM Bracket, has been evaluated.This development studies the manufacturing and assembly feasibility making use of these CFRP technologies.This study also compares traditional metallic solutions with innovative CFRP ones in terms of mechanical performances at elementary level. Weight and cost of presented solutions are also compared.

  11. Interfacing Sail Modules for Use with “Space Tugs”

    Directory of Open Access Journals (Sweden)

    Florio Dalla Vedova

    2018-05-01

    Full Text Available The paper introduces and describes the recent and still ongoing development activities performed in Luxembourg for In-Orbit Attach Mechanisms for (Drag Sails Modules to be operated from Space Tugs. After some preparatory work aiming at understanding the possible operational aspects and implications of mating interfaces between these space systems, three possible designs of In-Orbit Attach Mechanisms have been proposed and completed for their 3D (Metal and Plastic Printing, a new manufacturing technology assessed within this project. The Plastic-printed prototype underwent a series of automated tests in which a robotic arm, equipped with an advanced force sensor, replicated four docking scenarii in ideal and degraded modes. The observation of the forces and torque behaviors at and after impact allowed one to characterize the typical patterns for the various contacts but also, to identify a type of potentially dramatic impact for the safety of the docking and its equipment: in the case of the off-axis approach, “point” contacts shall be avoided, as they instantaneously transfer the total kinetic energy in a small area that could break.

  12. Weather Support for the 2008 Olympic and Paralympic Sailing Events

    Directory of Open Access Journals (Sweden)

    Yan Ma

    2013-01-01

    Full Text Available The Beijing 2008 Olympic and Paralympic Sailing Competitions (referred to as OPSC hereafter were held at Qingdao during August 9–23 and September 7–13 2008, respectively. The Qingdao Meteorological Bureau was the official provider of weather support for the OPSC. Three-dimensional real-time information with high spatial-temporal resolution was obtained by the comprehensive observation system during the OPSC, which included weather radars, wind profile radars, buoys, automated weather stations, and other conventional observations. The refined forecasting system based on MM5, WRF, and statistical modules provided point-specific hourly wind forecasts for the five venues, and the severe weather monitoring and forecasting system was used in short-term forecasts and nowcasts for rainstorms, gales, and hailstones. Moreover, latest forecasting products, warnings, and weather information were communicated conveniently and timely through a synthetic, speedy, and digitalized network system to different customers. Daily weather information briefings, notice boards, websites, and community short messages were the main approaches for regatta organizers, athletes, and coaches to receive weather service products at 8:00 PM of each day and whenever new updates were available. During the period of OPSC, almost one hundred people were involved in the weather service with innovative service concept, and the weather support was found to be successful and helpful to the OPSC.

  13. The influence of a yacht's heeling stability on optimum sail design

    Science.gov (United States)

    Sneyd, A. D.; Sugimoto, T.

    1997-01-01

    This paper presents fundamental results concerning the optimum design of yacht sails and masts. The aerodynamics of a high aspect ratio sail in uniform flow is analysed using lifting line theory to maximise thrust for a given sail area. The novel feature of this work is that thrust is optimised subject to the constraint that the aerodynamic heeling moment generated by the sail is balanced by the righting moment due to hull buoyancy (and the weight of the keel). Initially, the heel angle is therefore unknown, and determined as part of the solution process. Under the assumption of small heel angle, the problem reduces to minimising a quadratic form in the Fourier coefficients for the circulation distribution along the mast, and a simple analytic solution can be derived. It is found that if the mast is too high, the upper section is unused, and as a consequence there is a theoretically ideal mast height for a yacht of given heeling stability. Under the constraints of given sail area and heeling equilibrium it is found that no advantage is to be gained by allowing reverse circulation near the top of the mast. Various implications for yacht performance are discussed.

  14. 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.

  15. 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.

  16. Propellantless Attitude Control of Solar Sail Technology Utilizing Reflective Control Devices

    Science.gov (United States)

    Munday, Jeremy

    2016-01-01

    Solar sails offer an opportunity for a CubeSatscale, propellant-free spacecraft technology that enables long-term and long-distance missions not possible with traditional methods. Solar sails operate using the transfer of linear momentum from photons of sunlight reflected from the surface of the sail. To propel the spacecraft, no mechanically moving parts, thrusters, or propellant are needed. However, attitude control, or orientation, is still performed using traditional methods involving reaction wheels and propellant ejection, which severely limit mission lifetime. For example, the current state of the art solutions employed by upcoming missions couple solar sails with a state of the art propellant ejection gas system. Here, the use of the gas thruster has limited the lifetime of the mission. To solve the limited mission lifetime problem, the Propellantless Attitude Control of Solar Sail Technology Utilizing Reflective Control Devices project team is working on propellantless attitude control using thin layers of material, an optical film, electrically switchable from transparent to reflective. The technology is based on a polymer-dispersed liquid crystal (PDLC), which allows this switch upon application of a voltage. This technology removes the need for propellant, which reduces weight and cost while improving performance and lifetime.

  17. On Impact Mechanics in Ship Collisions

    DEFF Research Database (Denmark)

    Pedersen, Preben Terndrup; Zhang, Shengming

    1998-01-01

    The purpose of this paper is to present analytical, closed-form expressions for the energy released for crushing and the impact impulse during ship collisions. Ship-ship collisions, ship collisions with rigid walls and ship collisions with flexible offshore structures are considered. The derived ...

  18. Luggage and shipped goods

    International Nuclear Information System (INIS)

    Vogel, H.; Haller, D.

    2007-01-01

    Summary: Purpose: Control of luggage and shipped goods are frequently carried out. The possibilities of X-ray technology shall be demonstrated. Materials and methods: There are different imaging techniques. The main concepts are transmission imaging, backscatter imaging, computed tomography, and dual energy imaging and the combination of different methods The images come from manufacturers and personal collections. Results: The search concerns mainly, weapons, explosives, and drugs; furthermore animals, and stolen goods, Special problems offer the control of letters and the detection of Improvised Explosive Devices (IED). Conclusion: One has to expect that controls will increase and that imaging with X-rays will have their part. Pattern recognition software will be used for analysis enforced by economy and by demand for higher efficiency - man and computer will produce more security than man alone

  19. Global Shipping Game

    Science.gov (United States)

    2011-01-28

    information please contact the Chairman, War Gaming Department, Naval War College, 686 Cushing Road, Newport, RI 02841 or via electronic mail at... Game ……………………………………………...9 c. Overarching Research Question……………………………………………..…10 d. Subsidiary Questions…………………………………………………………...10 e ...An e -SLOC is the “cyber network that supports the global maritime trade network.” Industry Global Shipping Game Report 27 experts felt that

  20. Single liner shipping service design

    DEFF Research Database (Denmark)

    Plum, Christian Edinger Munk; Pisinger, David; Salazar-González, Juan-José

    2014-01-01

    The design of container shipping networks is an important logistics problem, involving assets and operational costs measured in billions of dollars. To guide the optimal deployment of the ships, a single vessel round trip is considered by minimizing operational costs and flowing the best paying...

  1. Towards a nuclear merchant ship

    International Nuclear Information System (INIS)

    Nicholson, R.L.R.; Llewelyn, G.I.W.; Farmer, A.A.

    1976-01-01

    The operation of nuclear merchant ships is likely to be attended by a number of constraints and requirements. Not all of these can be fully resolved until such ships come into use and the necessary experience and confidence have been acquired. But the timing of commercial introduction, if it comes about, will depend on the relative economics of nuclear versus fossil fuel propulsion, and the differences in turn depend in part on the operating costs particular to nuclear ships. A review of operation aspects is essential not only to commercial appraisal; each country whose trade may be carried in nuclear ships - whether it will build such ships or not - will have occasion to give some attention to the problems. It is an international problem and is, as noted later, being considered internationally. This paper; i) reviews some of the operational aspects as seen in the U.K.; ii) summarizes views received by the Nuclear Merchant Ship Unit (NMSU) from U.K. shipping, shipbuilding and nuclear industries on the prospects of a U.K. nuclear merchant ship. (author)

  2. Ship exhaust gas plume cooling

    NARCIS (Netherlands)

    Schleijpen, H.M.A.; Neele, P.P.

    2004-01-01

    The exhaust gas plume is an important and sometimes dominating contributor to the infrared signature of ships. Suppression of the infrared ship signatures has been studied by TNO for the Royal Netherlands Navy over considerable time. This study deals with the suppression effects, which can be

  3. Navy Hospital ships in history

    Directory of Open Access Journals (Sweden)

    Sougat Ray

    2017-01-01

    Full Text Available Hospital ships are operated by the Naval forces in or near war zones to provide medical assistance to the wounded personnel of all nationalities and not be used for any military purpose. Hospital ships possibly existed in ancient times and the Athenian Navy had a ship named Therapia. However, it was only during the 17th century that it became a common practice for the naval squadrons to be accompanied by large ships with the facilities of carrying the wounded after each engagement. In 1860, the steamships HMS Melbourne and HMS Mauritius were equipped with genuine medical facilities. They were manned by the Medical Staff Corps and provided services to the British expedition to China. During the World War I and World War II, passenger ships were converted for use as hospital ships and were started to be used on a massive scale. RMS Aquitania and HMHS Britannic were two famous examples of hospital ships used extensively. Modern US hospital ships USNS Mercy and USNS Comfort are operated by Military Sealift Command of the US Navy. Their primary mission is to provide emergency on-site care for US combatant forces deployed in war or other operations.

  4. 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

  5. Sunlight reflection off the spacecraft with a solar sail on the surface of mars

    Science.gov (United States)

    Starinova, O. L.; Rozhkov, M. A.; Gorbunova, I. V.

    2018-05-01

    Modern technologies make it possible to fulfill many projects in the field of space exploration. One such project is the colonization of Mars and providing favorable conditions for living on it. Authors propose principles of functioning of the spacecraft with a solar sail, intended to create a thermal and light spot in a predetermined area of the Martian surface. This additional illumination can maintain and support certain climatic conditions on a small area where a Mars base could be located. This paper investigate the possibility of the spacecraft continuously reflect the sunlight off the solar sail on the small area of the Mars surface. The mathematical motion model in such condition of the solar sail's orientation is considered and used for motion simulation session. Moreover, the analysis of this motion is performed. Thus, were obtained parameters of the synchronic non-Keplerian orbit and spacecraft construction. In addition, were given recommendations for further applying satellites to reflect the sunlight on a planet's surface.

  6. 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.

  7. SAIL--a software system for sample and phenotype availability across biobanks and cohorts.

    Science.gov (United States)

    Gostev, Mikhail; Fernandez-Banet, Julio; Rung, Johan; Dietrich, Joern; Prokopenko, Inga; Ripatti, Samuli; McCarthy, Mark I; Brazma, Alvis; Krestyaninova, Maria

    2011-02-15

    The Sample avAILability system-SAIL-is a web based application for searching, browsing and annotating biological sample collections or biobank entries. By providing individual-level information on the availability of specific data types (phenotypes, genetic or genomic data) and samples within a collection, rather than the actual measurement data, resource integration can be facilitated. A flexible data structure enables the collection owners to provide descriptive information on their samples using existing or custom vocabularies. Users can query for the available samples by various parameters combining them via logical expressions. The system can be scaled to hold data from millions of samples with thousands of variables. SAIL is available under Aferro-GPL open source license: https://github.com/sail.

  8. Identification of Dynamically Positioned Ships

    Directory of Open Access Journals (Sweden)

    Thor I. Fossen

    1996-04-01

    Full Text Available Todays model-based dynamic positioning (DP systems require that the ship and thruster dynamics are known with some accuracy in order to use linear quadratic optical control theory. However, it is difficult to identify the mathematical model of a dynamically posititmed (DP ship since the ship is not persistently excited under DP. In addition the ship parameter estimation problem is nonlinear and multivariable with only position and thruster state measurements available for parameter estimation. The process and measurement noise must also be modeled in order to avoid parameter drift due to environmental disturbances and sensor failure. This article discusses an off-line parallel extended Kalman filter (EKF algorithm utilizing two measurement series in parallel to estimate the parameters in the DP ship model. Full-scale experiments with a supply vessel are used to demonstrate the convergence and robustness of the proposed parameter estimator.

  9. High energy gain in three-dimensional simulations of light sail acceleration

    Energy Technology Data Exchange (ETDEWEB)

    Sgattoni, A., E-mail: andrea.sgattoni@polimi.it [Dipartimento di Energia, Politecnico di Milano, Milano (Italy); CNR, Istituto Nazionale di Ottica, u.o.s. “Adriano Gozzini,” Pisa (Italy); Sinigardi, S. [CNR, Istituto Nazionale di Ottica, u.o.s. “Adriano Gozzini,” Pisa (Italy); Dipartimento di Fisica e Astronomia, Università di Bologna, Bologna (Italy); INFN sezione di Bologna, Bologna (Italy); Macchi, A. [CNR, Istituto Nazionale di Ottica, u.o.s. “Adriano Gozzini,” Pisa (Italy); Dipartimento di Fisica “Enrico Fermi,” Università di Pisa, Pisa (Italy)

    2014-08-25

    The dynamics of radiation pressure acceleration in the relativistic light sail regime are analysed by means of large scale, three-dimensional (3D) particle-in-cell simulations. Differently to other mechanisms, the 3D dynamics leads to faster and higher energy gain than in 1D or 2D geometry. This effect is caused by the local decrease of the target density due to transverse expansion leading to a “lighter sail.” However, the rarefaction of the target leads to an earlier transition to transparency limiting the energy gain. A transverse instability leads to a structured and inhomogeneous ion distribution.

  10. 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.

  11. 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.

  12. Towing Asteroids with Gravity Tractors Enhanced by Tethers and Solar Sails

    Science.gov (United States)

    Shen, Haijun; Roithmayr, Carlos M.

    2015-01-01

    Material collected from an asteroid's surface can be used to increase gravitational attraction between the asteroid and a Gravity Tractor (GT); the spacecraft therefore operates more effectively and is referred to as an Enhanced Gravity Tractor (EGT). The use of tethers and solar sails to further improve effectiveness and simplify operations is investigated. By employing a tether, the asteroidal material can be placed close to the asteroid while the spacecraft is stationed farther away, resulting in a better safety margin and improved thruster efficiency. A solar sail on a spacecraft can naturally provide radial offset and inter-spacecraft separation required for multiple EGTs.

  13. High energy gain in three-dimensional simulations of light sail acceleration

    International Nuclear Information System (INIS)

    Sgattoni, A.; Sinigardi, S.; Macchi, A.

    2014-01-01

    The dynamics of radiation pressure acceleration in the relativistic light sail regime are analysed by means of large scale, three-dimensional (3D) particle-in-cell simulations. Differently to other mechanisms, the 3D dynamics leads to faster and higher energy gain than in 1D or 2D geometry. This effect is caused by the local decrease of the target density due to transverse expansion leading to a “lighter sail.” However, the rarefaction of the target leads to an earlier transition to transparency limiting the energy gain. A transverse instability leads to a structured and inhomogeneous ion distribution.

  14. One kilometer (1 km) electric solar wind sail tether produced automatically.

    Science.gov (United States)

    Seppänen, Henri; Rauhala, Timo; Kiprich, Sergiy; Ukkonen, Jukka; Simonsson, Martin; Kurppa, Risto; Janhunen, Pekka; Hæggström, Edward

    2013-09-01

    We produced a 1 km continuous piece of multifilament electric solar wind sail tether of μm-diameter aluminum wires using a custom made automatic tether factory. The tether comprising 90,704 bonds between 25 and 50 μm diameter wires is reeled onto a metal reel. The total mass of 1 km tether is 10 g. We reached a production rate of 70 m/24 h and a quality level of 1‰ loose bonds and 2‰ rebonded ones. We thus demonstrated that production of long electric solar wind sail tethers is possible and practical.

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

    International Nuclear Information System (INIS)

    Hoshi, Kento; Kojima, Hirotsugu; Yamakawa, Hiroshi; Muranaka, Takanobu

    2016-01-01

    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. Economic Cost of an Algae Bloom Cleanup in China's 2008 Olympic Sailing Venue

    Science.gov (United States)

    Wang, X. H.; Li, L.; Bao, X.; Zhao, L. D.

    2009-07-01

    In the summer of 2008, an algae bloom struck the coast of Qingdao, China, where the 2008 Olympic sailing events were to be held. The bloom was caused by the drift and proliferation of the green algae Enteromorpha (see http://precedings.nature.com/documents/2352/version/1). It lasted for more than 1 month and covered nearly the entire sailing venue. The Enteromorpha bloom was so intense that national and local governments invested a tremendous amount of labor and resources in a cleanup effort in order to achieve Olympic Games standards [Hu and He, 2008].

  17. [Medical services on an inspection ship in the north Atlantic].

    Science.gov (United States)

    Kjaer, A

    1990-10-29

    The Danish Naval Inspection Ships sail in the North Atlantic waters with a doctor on board. The object of this investigation was to illustrate the medical services on board and to elucidate the significance of various factors to predict seeking medical advice. During a period of three months, all of the medical services and certain basic factors were registered. The crew was interviewed about consumption of alcohol and tobacco, previous life at sea and family background. A total of 305 consultations were used by the crew of 72 men. This figure is five times the anticipated figure in general practice. Low rank and low age were predictors for frequent medical consultations. The diagnosis groups of traumata/injuries, dermatological conditions and disease in the nervous system or organs of sense were relatively overrepresented. A series of factors may possibly have influenced the pattern of seeking medical help so that this differs from general practice. It is concluded that the dangerous working environment and poor possibilities for good hygiene are important factors whereas the mental stress is of lesser significance.

  18. Cybersecurity Framework for Ship Industrial Control System

    OpenAIRE

    Maule, R. William; Hake, Joseph

    2016-01-01

    Ship mechanical and electrical control systems, and the communications grid through which these devices operate, are a high priority concern for Navy leadership. Ship systems use microprocessor-based controls to interface with physical objects, and Programmable Logic Controllers (PLCs) to automate ship electromechanical processes. Ship operations are completely dependent on these devices. The commercial security products upon which ships depend do not work on ICS, leaving ships vulnerable. Th...

  19. Containment of spills from ships

    International Nuclear Information System (INIS)

    Engerer, M.J.

    1992-01-01

    Oil escaping from a ship is contained within a limited area surrounding the ship by means of a flexible ring structure. The ring structure is stored in a collapsed state in a compartment extending around the ship. In response to an oil spill, the ring structure is dropped from the compartment and immediately surrounds the ship. A circular inflatable flotation section of the ring structure is charged with gas under pressure. The gas is supplied from a bottle cascade aboard the ship, through lines preconnected to the flotation section and paid out from free-wheeling reels. The flotation section supports a thin circumferential wall of predetermined height that submerges and assumes a vertical cylinder-like shape surrounding the escaping oil. The oil floats within the confines of the ring structure, and the ring structure is progressively expanded to a predetermined size selected to accommodate the total volume of oil carried by the ship. When the ring structure achieves its expanded state, pressure in the flotation section is raised to render the structure relatively rigid and resistant to collapse in response to wave action. Oil can be removed from the interior of the ring structure by recovery ships using suction lines or other conventional recovery methods. 12 figs

  20. Ships and the Sailors Inside Them

    National Research Council Canada - National Science Library

    Sims, Philip

    2004-01-01

    .... Iron shipbuilding allowed safer and healthier ships but their internal compartmentation created communication problems which were gradually solved with mechanical systems Ships developed their own...

  1. Bio-indications of sunken ships and ship wrecks

    Digital Repository Service at National Institute of Oceanography (India)

    Parulekar, A

    An evaluation of bottom fauna of ship-wreck sites in estuarine and coastal waters of Goa, India, revealed an exceptionally high biotic enrichment. In terms of number of species, faunal dispersion, faunal diversity, biomass and productivity, in space...

  2. Neutrino physics with SHIP

    CERN Document Server

    van Herwijnen, Eric

    2016-01-01

    SHIP is a new general purpose fixed target facility, whose Technical Proposal has been recently reviewed by the CERN SPS Committee. It recommended that the experiment proceed further to a Comprehensive Design phase. In its initial phase, the 400 GeV proton beam extracted from the SPS will be dumped on a heavy target with the aim of integrating 2×1020 POT (Protons On Target) in 5 years. A dedicated detector, based on a long vacuum tank followed by a spectrometer and particle identification detectors, will allow probing a variety of models with light long-lived exotic particles and masses below O(10) GeV/c 2 . The main focus will be the physics of the so-called Hidden Portals. The sensitivity to Heavy Neutrinos will allow to probe for the first time the mass range between the kaon and the charm meson mass, and a range of couplings for which Baryogenesis and active neutrino masses could also be explained. Another dedicated detector will allow the study of neutrino cross-sections and angular distributions. ντ ...

  3. Production Balance of Ship Erection

    Institute of Scientific and Technical Information of China (English)

    JIANG Ru-hong; TAN Jia-hua; LIU Cun-gen

    2008-01-01

    A network plan model of ship erection was established based on the network planning technologyand the work-package breakdown system. The load-oriented production control method was introduced to buildup a throughput diagram model thus it is possible to describe the ship erection process numerically. Based onthe digitaiized models some cases of production balance of ship erection were studied and three balance indexeswere put forward, they are the load balance rate, the input manpower balance rate and the maximum gantrycrane operating times. Such an analytic method based on the balance evaluation is the important foundationfor digitization and intelligentization of shipyard production management.

  4. Formal Safety Assessment (FSA for Analysis of Ship Collision Using AIS Data

    Directory of Open Access Journals (Sweden)

    Muhammad Badrus Zaman

    2015-03-01

    Full Text Available Currently, Maritime safety is the best issue in the world. International Maritime organization (IMO have recommended FSA methodology to enhance maritime safety. In this paper, the research conducted in the Malacca Strait. Malacca Strait is an area that has a high risk for shipping navigation. Many accidents occur in the area are like collision, fire, grounding and so on. Therefore a study on improving safety in this area is very important. it is to produce an output that can be used to provide input to the master and multiple stakeholders to improve safety on board at the time of sailing. In this study, AIS is used as a data source. Sea condition data collected actual traffic through the Automatic Identification System (AIS equipment installed at Kobe University, Japan, and Universiti Teknologi Malaysia (UTM in Johor, Malaysia. The data is applied to define a method with the help of Geographic Information Systems (GIS.

  5. Ship-Iceberg Discrimination in Sentinel-2 Multispectral Imagery by Supervised Classification

    Directory of Open Access Journals (Sweden)

    Peder Heiselberg

    2017-11-01

    Full Text Available 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 Arctic environment. We analyze several sets of multispectral image data from Denmark and Greenland fall and winter, and describe a supervised search and classification algorithm based on physical parameters that successfully finds and classifies all objects in the sea with reflectance above a threshold. It discriminates between objects like ships, islands, wakes, and icebergs, ice floes, and clouds with accuracy better than 90%. Pan-sharpening the infrared bands leads to classification and discrimination of ice floes and clouds better than 95%. For complex images with abundant ice floes or clouds, however, the false alarm rate dominates for small non-sailing boats.

  6. The Effect of Hull Biofouling on Parameters Characterising Ship Propulsion System Efficiency

    Directory of Open Access Journals (Sweden)

    Tarełko Wiesła

    2015-01-01

    Full Text Available One of most important issues concerning technical objects is the increase of their operating performance. For a ship this performance mainly depends on the efficiency of its main pro-pulsion system and the resistance generated during its motion on water. The overall ship re-sistance, in turn, mainly depends on the hull friction resistance, closely related with the pres-ence of different types of roughness on the hull surface, including underwater part biofouling. The article analyses the effect of hull biofouling on selected parameters characterising the efficiency of the ship propulsion system with adjustable propeller. For this purpose a two-year research experiment was performed on a sailing vessel during its motor navigation phases. Based on the obtained results, three groups of characteristics were worked out for different combinations of engine rotational speed and adjustable propeller pitch settings. The obtained results have revealed that the phenomenon of underwater hull biofouling affects remarkably the parameters characterising propulsion system efficiency. In particular, the development of the biofouling layer leads to significant reduction of the speed of navigation.

  7. 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 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.

  8. Potential risks of nuclear ships

    International Nuclear Information System (INIS)

    Oelgaard, P.L.

    1994-07-01

    This report represents an attempt to evaluate the potential risks of nuclear ships. Firstly reasons are given why nuclear ship accidents will not lead to accidents of the magnitude of the Chernobyl accident. This is due to much lower content of radioactive material and to different reactor designs. Next a review is given of the types of accidents which have actually occurred. Of these the reactor accidents which may lead to serious consequences for the crew and the environment are considered further. These are reactivity accidents and loss of coolant accidents. In addition the long term risks of sunken nuclear ships and sea disposed reactor compartments etc. are also discussed. Based on available accident data an attempt is made to estimate the probability of serious nuclear ship accidents. (au)

  9. Occupational accidents aboard merchant ships

    DEFF Research Database (Denmark)

    Hansen, H.L.; Nielsen, D.; Frydenberg, Morten

    2002-01-01

    Objectives: To investigate the frequency, circumstances, and causes of occupational accidents aboard merchant ships in international trade, and to identify risk factors for the occurrence of occupational accidents as well as dangerous working situations where possible preventive measures may...... be initiated. Methods: The study is a historical follow up on occupational accidents among crew aboard Danish merchant ships in the period 1993–7. Data were extracted from the Danish Maritime Authority and insurance data. Exact data on time at risk were available. Results: A total of 1993 accidents were...... aboard. Relative risks for notified accidents and accidents causing permanent disability of 5% or more were calculated in a multivariate analysis including ship type, occupation, age, time on board, change of ship since last employment period, and nationality. Foreigners had a considerably lower recorded...

  10. Travelers' Health: Cruise Ship Travel

    Science.gov (United States)

    ... and territories). Zika virus was first reported in Brazil in 2015 and subsequently spread across the Caribbean ... 11. Mouchtouri VA, Rudge JW. Legionnaires’ disease in hotels and passenger ships: a systematic review of evidence, ...

  11. Ship Repair Workflow Cost Model

    National Research Council Canada - National Science Library

    McDevitt, Mike

    2003-01-01

    The effects of intermittent work patterns and funding on the costs of ship repair and maintenance were modeled for the San Diego region in 2002 for Supervisor of Shipbuilding and Repair (SUPSHIP) San Diego...

  12. 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...

  13. 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.

  14. Deep Play. Rationality in the Life World with Special Reference to Sailing

    Science.gov (United States)

    Goold, Patrick

    2014-01-01

    In an essay on the rationality of play, the author characterizes rationality by the three distinct demands it makes on the individual--demands for autonomy, solidarity, and integrity. He develops each of these as they apply to the sport of sailing, using the example of two deep-ocean expeditions to arrive at a concept of deep play he sees as one…

  15. 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

  16. LQR pitch control strategy of AUVs based on the optimum of sailing resistance

    Directory of Open Access Journals (Sweden)

    YAO Xuliang

    2017-05-01

    Full Text Available When an Autonomous Underwater Vehicle(AUV sails near the surface of the sea,it will inevitably be subjected to wave disturbance. The heave and pitch motion caused by wave disturbance not only affects the navigation attitude of the AUV,but also leads to an increase in sailing resistance. As such, its energy consumption is increased. In this paper,the six degrees of freedom model of AUVs is established and linearized in order to achieve the weighted optimization of the sailing attitude and the resistance of the AUVs. The drag force model of the AUV is derived using the theory of potential flow. The Q matrix and R matrix are determined in the controller based on research into the drag force model. The Linear Quadratic Regulator(LQRcontroller of the AUV is designed using the drag force model as the performance index. The simulation results show that after adding the LQR controller,the effects of reducing heave motion and pitch motion are 46.64% and 77.62% respectively, and the increased resistance caused by the pitch motion is reduced to 1/6 of its original value. The results show that the multiple optimum of attitude and sailing resistance is realized,the energy consumption is decreased and the endurance of the AUV is increased.

  17. 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.

  18. 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...

  19. Thrust and torque vector characteristics of axially-symmetric E-sail

    Science.gov (United States)

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

    2018-05-01

    The Electric Solar Wind Sail is an innovative propulsion system concept that gains propulsive acceleration from the interaction with charged particles released by the Sun. The aim of this paper is to obtain analytical expressions for the thrust and torque vectors of a spinning sail of given shape. Under the only assumption that each tether belongs to a plane containing the spacecraft spin axis, a general analytical relation is found for the thrust and torque vectors as a function of the spacecraft attitude relative to an orbital reference frame. The results are then applied to the noteworthy situation of a Sun-facing sail, that is, when the spacecraft spin axis is aligned with the Sun-spacecraft line, which approximatively coincides with the solar wind direction. In that case, the paper discusses the equilibrium shape of the generic conducting tether as a function of the sail geometry and the spin rate, using both a numerical and an analytical (approximate) approach. As a result, the structural characteristics of the conducting tether are related to the spacecraft geometric parameters.

  20. 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.

  1. [Estimation of forest canopy chlorophyll content based on PROSPECT and SAIL models].

    Science.gov (United States)

    Yang, Xi-guang; Fan, Wen-yi; Yu, Ying

    2010-11-01

    The forest canopy chlorophyll content directly reflects the health and stress of forest. The accurate estimation of the forest canopy chlorophyll content is a significant foundation for researching forest ecosystem cycle models. In the present paper, the inversion of the forest canopy chlorophyll content was based on PROSPECT and SAIL models from the physical mechanism angle. First, leaf spectrum and canopy spectrum were simulated by PROSPECT and SAIL models respectively. And leaf chlorophyll content look-up-table was established for leaf chlorophyll content retrieval. Then leaf chlorophyll content was converted into canopy chlorophyll content by Leaf Area Index (LAD). Finally, canopy chlorophyll content was estimated from Hyperion image. The results indicated that the main effect bands of chlorophyll content were 400-900 nm, the simulation of leaf and canopy spectrum by PROSPECT and SAIL models fit better with the measured spectrum with 7.06% and 16.49% relative error respectively, the RMSE of LAI inversion was 0. 542 6 and the forest canopy chlorophyll content was estimated better by PROSPECT and SAIL models with precision = 77.02%.

  2. Dynamic and optical characterization of dusty plasmas for use as solar sails

    International Nuclear Information System (INIS)

    Sheldon, Robert; Thomas, Edward Jr.; Abbas, Mian; Gallagher, Dennis; Adrian, Mark; Craven, Paul

    2002-01-01

    Solar sails presently have mass loadings of 5 gm/m2 that, when including the support structure and payload, could easily average to >10 gm/m2. For reasonably sized spacecraft, the critical parameter is the total mass per total area, which when combined with the reflectivity, yield the true acceleration. We propose that dusty plasmas trapped in a 'Mini-Magnetosphere' (Winglee, 2000) can produce a solar sail with a total mass loading <0.01 gm/m2, and reflectivities of ∼1%. This configuration provides an acceleration equivalent to a standard sail of 95% reflectivity with <1 gm/m2. However, the physics of dusty plasma sails is not mature and several important questions need to be resolved before a large scale effort is warranted. Foremost among these questions are, what is the largest force a dusty plasma can sustain before it demagnetizes and separates from the binding magnetic field; what are the charging properties of dust under solar UV conditions; what is the light scattering cross section for the dust; what is the optimum dust grain size for magnetization and scattering; and, what are the optimum dust grain materials? We outline what we know about dusty plasmas, and what we are hoping to learn from two existing dusty plasma experiments at the National Space Science and Technology Center (NSSTC) and Auburn University

  3. SAIL--A Way to Success and Independence for Low-Achieving Readers.

    Science.gov (United States)

    Bergman, Janet L.

    1992-01-01

    Argues that providing students with a repertoire of important learning strategies is one crucial way of helping all students to become independent readers, thinkers, and learners. Describes a third grade reading environment and the practices of the Students Achievement Independent Learning Program (SAIL). (PRA)

  4. Coastal Fishermen as Lifesavers While Sailing at High Speed: A Crossover Study

    Directory of Open Access Journals (Sweden)

    Ramón Fungueiriño-Suárez

    2018-01-01

    Full Text Available Purpose. Starting basic cardiopulmonary resuscitation (CPR early improves survival. Fishermen are the first bystanders while at work. Our objective was to test in a simulated scenario the CPR quality performed by fishermen while at port and while navigating at different speeds. Methods. Twenty coastal fishermen were asked to perform 2 minutes of CPR (chest compressions and mouth-to-mouth ventilations on a manikin, in three different scenarios: (A at port on land, (B on the boat floor sailing at 10 knots, and (C sailing at 20 knots. Data was recorded using quality CPR software, adjusted to current CPR international guidelines. Results. The quality of CPR (QCPR was significantly higher at port (43%±10 than sailing at 10 knots (30%±15; p=0.01 or at 20 knots (26%±12; p=0.001. The percentage of ventilation that achieved some lung insufflation was also significantly higher when CPR was done at port (77%±14 than while sailing at 10 knots (59%±18 or 20 knots (57%±21 (p=0.01. Conclusion. In the event of drowning or cardiac arrest on a small boat, fishermen should immediately start basic CPR and navigate at a relatively high speed to the nearest port if the sea conditions are safe.

  5. TMI-2 spent fuel shipping

    International Nuclear Information System (INIS)

    Quinn, G.J.; Burton, H.M.

    1985-01-01

    TMI-2 failed fuel will be shipped to the Idaho National Engineering Laboratory for use in the DOE Core Examination Program. The fuel debris will be loaded into three types of canisters during defueling and dry loaded into a spent fuel shipping cask. The cask design accommodates seven canisters per cask and has two separate containment vessels with ''leaktight'' seals. Shipments are expectd to begin in early 1986

  6. 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

  7. 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

  8. 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.

  9. 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.

  10. Deceleration of High-velocity Interstellar Photon Sails into Bound Orbits at α Centauri

    Energy Technology Data Exchange (ETDEWEB)

    Heller, René [Max Planck Institute for Solar System Research Justus-von-Liebig-Weg 3, 37077 Göttingen (Germany); Hippke, Michael, E-mail: heller@mps.mpg.de, E-mail: hippke@ifda.eu [Luiter Straße 21b, 47506 Neukirchen-Vluyn (Germany)

    2017-02-01

    At a distance of about 4.22 ly, it would take about 100,000 years for humans to visit our closest stellar neighbor Proxima Centauri using modern chemical thrusters. New technologies are now being developed that involve high-power lasers firing at 1 gram solar sails in near-Earth orbits, accelerating them to 20% the speed of light ( c ) within minutes. Although such an interstellar probe could reach Proxima 20 years after launch, without propellant to slow it down it would traverse the system within hours. Here we demonstrate how the stellar photon pressures of the stellar triple α Cen A, B, and C (Proxima) can be used together with gravity assists to decelerate incoming solar sails from Earth. The maximum injection speed at α Cen A to park a sail with a mass-to-surface ratio ( σ ) similar to graphene (7.6 × 10{sup −4} gram m{sup −2}) in orbit around Proxima is about 13,800 km s{sup −1} (4.6% c ), implying travel times from Earth to α Cen A and B of about 95 years and another 46 years (with a residual velocity of 1280 km s{sup −1}) to Proxima. The size of such a low- σ sail required to carry a payload of 10 grams is about 10{sup 5} m{sup 2} = (316 m){sup 2}. Such a sail could use solar photons instead of an expensive laser system to gain interstellar velocities at departure. Photogravitational assists allow visits of three stellar systems and an Earth-sized potentially habitable planet in one shot, promising extremely high scientific yields.

  11. 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.

  12. Deceleration of High-velocity Interstellar Photon Sails into Bound Orbits at α Centauri

    International Nuclear Information System (INIS)

    Heller, René; Hippke, Michael

    2017-01-01

    At a distance of about 4.22 ly, it would take about 100,000 years for humans to visit our closest stellar neighbor Proxima Centauri using modern chemical thrusters. New technologies are now being developed that involve high-power lasers firing at 1 gram solar sails in near-Earth orbits, accelerating them to 20% the speed of light ( c ) within minutes. Although such an interstellar probe could reach Proxima 20 years after launch, without propellant to slow it down it would traverse the system within hours. Here we demonstrate how the stellar photon pressures of the stellar triple α Cen A, B, and C (Proxima) can be used together with gravity assists to decelerate incoming solar sails from Earth. The maximum injection speed at α Cen A to park a sail with a mass-to-surface ratio ( σ ) similar to graphene (7.6 × 10"−"4 gram m"−"2) in orbit around Proxima is about 13,800 km s"−"1 (4.6% c ), implying travel times from Earth to α Cen A and B of about 95 years and another 46 years (with a residual velocity of 1280 km s"−"1) to Proxima. The size of such a low- σ sail required to carry a payload of 10 grams is about 10"5 m"2 = (316 m)"2. Such a sail could use solar photons instead of an expensive laser system to gain interstellar velocities at departure. Photogravitational assists allow visits of three stellar systems and an Earth-sized potentially habitable planet in one shot, promising extremely high scientific yields.

  13. On impact mechanics in ship collisions

    DEFF Research Database (Denmark)

    Pedersen, Preben Terndrup; Zhang, Shengming

    1998-01-01

    The purpose of this paper is to present analytical, closed-form expressions for the energy released for crushing and the impact impulse during ship collisions. Ship–ship collisions, ship collisions with rigid walls and ship collisions with flexible offshore structures are considered. The derived ...

  14. Analysis for the amplitude oscillatory movements of the ship in response to the incidence wave

    Science.gov (United States)

    Chiţu, M. G.; Zăgan, R.; Manea, E.

    2015-11-01

    Event of major accident navigation near offshore drilling rigs remains unacceptably high, known as the complications arising from the problematic of the general motions of the ship sailing under real sea. Dynamic positioning system is an effective instrument used on board of the ships operating in the extraction of oil and gas in the continental shelf of the seas and oceans, being essential that the personnel on board of the vessel can maintain position and operating point or imposed on a route with high precision. By the adoption of a strict safety in terms of handling and positioning of the vessel in the vicinity of the drilling platform, the risk of accidents can be reduced to a minimum. Possibilities in anticipation amplitudes of the oscillatory movements of the ships navigating in real sea, is a challenge for naval architects and OCTOPUS software is a tool used increasingly more in this respect, complementing navigational facilities offered by dynamic positioning systems. This paper presents a study on the amplitudes of the oscillations categories of supply vessels in severe hydro meteorological conditions of navigation. The study provides information on the RAO (Response Amplitude Operator) response operator of the ship, for the amplitude of the roll movements, in some incident wave systems, interpreted using the energy spectrum Jonswap and whose characteristics are known (significant height of the wave, wave period, pulsation of the wave). Ship responses are analyzed according to different positioning of the ship in relation to the wave front (incident angle ranging from 10 to 10 degree from 0 to 180), highlighting the value of the ship roll motion amplitude. For the study, was used, as a tool for modeling and simulation, the features offered by OCTOPUS software that allows the study of the computerized behavior of the ship on the waves, in the real conditions of navigation. Program library was used for both the vessel itself and navigation modeling

  15. Development of the nuclear ship MUTSU spent fuel shipping cask

    International Nuclear Information System (INIS)

    Ishizuka, M.; Umeda, M.; Nawata, Y.; Sato, H.; Honami, M.; Nomura, T.; Ohashi, M.; Higashino, A.

    1989-01-01

    After the planned trial voyage (4700 MWD/MTU) of the nuclear ship MUTSU in 1990, her spent fuel assemblies, initially made of two types of enriched UO 2 (3.2wt% and 4.4wt%), will be transferred to the reprocessing plant soon after cooling down in the ship reactor for more than one year. For transportation, the MUTSU spent fuel shipping casks will be used. Prior to transportation to the reprocessing plant, the cooled spent fuel assemblies will be removed from the reactor to the shipping casks and housed at the spent fuel storage facility on site. In designing the MUTSU spent fuel shipping cask, considerations were given to make the leak-tightness and integrity of the cask confirmable during storage. The development of the cask and the storage function demonstration test were performed by Japan Atomic Energy Research Institute (JAERI) and Mitsubishi Heavy Industries, Ltd. (MHI). One prototype cask for the storage demonstration test and licensed thirty-five casks were manufactured between 1987 and 1988

  16. Total Analysis System for Ship Structural Strength

    OpenAIRE

    Takuya, Yoneya; Hiroyuki, Kobayashi; Abdul M., Rahim; Yoshimichi, Sasaki; Masaki, Irisawa; Technical Investigation and Information Department, Research Center; Technical Investigation and Information Department, Research Center; Singapore Office; Technical Investigation and Information Department, Research Center; Technical Investigation and Information Department, Research Center

    2001-01-01

    This paper outlines a total analysis system for ship hull structures, which integrates a wide variety of analysis functions to realise practical applications of rational methods for assessing ship structural strength. It is based on direct calculation of wave-induced loads as well as three-dimensional structural analysis of an entire-ship or hold structure. Three major analysis functions of the total system are ship motion and wave load analysis, ship structural analysis and statistical analy...

  17. A PDDL Domain for the Liner Shipping Fleet Repositioning Problem

    DEFF Research Database (Denmark)

    Tierney, Kevin; Coles, Amanda; Coles, Andrew

    that are a function of their duration; for example, sailing slowly between two ports is cheaper than sailing quickly. Despite its great industrial importance, the LSFRP has received little attention in the literature. We model the LSFRP using PDDL and solve it using the planner....

  18. The impact of shipping emissions on air pollution in the greater North Sea region - Part 1: Current emissions and concentrations

    Science.gov (United States)

    Aulinger, A.; Matthias, V.; Zeretzke, M.; Bieser, J.; Quante, M.; Backes, A.

    2016-01-01

    The North Sea is one of the areas with the highest ship traffic densities worldwide. At any time, about 3000 ships are sailing its waterways. Previous scientific publications have shown that ships contribute significantly to atmospheric concentrations of NOx, particulate matter and ozone. Especially in the case of particulate matter and ozone, this influence can even be seen in regions far away from the main shipping routes. In order to quantify the effects of North Sea shipping on air quality in its bordering states, it is essential to determine the emissions from shipping as accurately as possible. Within Interreg IVb project Clean North Sea Shipping (CNSS), a bottom-up approach was developed and used to thoroughly compile such an emission inventory for 2011 that served as the base year for the current emission situation. The innovative aspect of this approach was to use load-dependent functions to calculate emissions from the ships' current activities instead of averaged emission factors for the entire range of the engine loads. These functions were applied to ship activities that were derived from hourly records of Automatic Identification System signals together with a database containing the engine characteristics of the vessels that traveled the North Sea in 2011. The emission model yielded ship emissions among others of NOx and SO2 at high temporal and spatial resolution that were subsequently used in a chemistry transport model in order to simulate the impact of the emissions on pollutant concentration levels. The total emissions of nitrogen reached 540 Gg and those of sulfur oxides 123 Gg within the North Sea - including the adjacent western part of the Baltic Sea until 5° W. This was about twice as much of those of a medium-sized industrialized European state like the Netherlands. The relative contribution of ships to, for example, NO2 concentration levels ashore close to the sea can reach up to 25 % in summer and 15 % in winter. Some hundred kilometers

  19. Transnucleaire's experience in ship adaptation

    International Nuclear Information System (INIS)

    Brachet, Y.; Vallette-Fontaine, M.

    2000-01-01

    Due to the application of the new IMDG regulations for the transport of radioactive material by sea, the conditions of transport of MTR spent fuel have drastically changed five years ago. In this paper, TRANSNUCLEAIRE analyses the necessary modifications to apply to existing ships in order to comply with the IMDG/INF regulations as well as with the Japanese KAISA 520 regulation. In the MTR spent fuel transport market characterized by a competitive approach, TRANSNUCLEAIRE has carried out many transports by sea in full compliance with the regulations at a price which is as close as possible to that of other industrial goods and without the need to fully dedicate the BOUGUENAIS ship to nuclear transports. Innovative ship design solutions have been implemented and accepted by different Authorities uncluding the Advisory Committee of the Japanese MOT. Due to efficient finite element calculations, benchmarked by laboratory large scale tests, high performances crushing materials have been developed in order to absorb the energy of collision between ships. These developments have led ta propose an efficient ship design complying with all the existing worldwide nuclear regulations. (author)

  20. Effect of Buffer Bow Structure in Ship-Ship Collision

    DEFF Research Database (Denmark)

    Yamada, Yasuhira; Endo, Hisayoshi; Pedersen, Preben Terndrup

    2008-01-01

    tankers, the introduction of buffer bulbous bows has been proposed. Relatively soft buffer bows absorb part of the kinetic energy of the striking ship before penetrating the inner hull of the struck vessel. The purpose of the present paper is to verify the effectiveness of a prototype buffer bulbous bow......) and the forward velocity of the struck ship on the collapse mode of the bow of the striking vessel are investigated. Collapse modes, contact forces and energy absorption capabilities of the buffer bows are compared with those of conventional bows....

  1. Canopy bidirectional reflectance calculation based on Adding method and SAIL formalism: AddingS / AddingSD

    NARCIS (Netherlands)

    Kallel, A.; Verhoef, W.; Hegarat-Mascle, Le S.; Ottle, C.; Hubert-Moy, L.

    2008-01-01

    The SAIL model (proposed by Verhoef) is largely used in the remote sensing community to calculate the canopy Bidirectional Reflectance Distribution Function. The simulation results appear acceptable compared to observations especially for not very dense planophile vegetation. However, for

  2. Evaluation of the potential to upgrade the Sandia Atomic Iodine Laser SAIL-1 to higher output energies

    International Nuclear Information System (INIS)

    Riley, M.E.; Palmer, R.E.

    1977-05-01

    The predicted output energy of the Sandia Atomic Iodine Laser SAIL-1 is given for various numbers of preamplifier stages and for various small signal gains in each stage. Additional possibilities for further increasing the output energy are given

  3. EX1001 Ship Shakedown (EX1001, EM302) on NOAA Ship Okeanos Explorer in Hawaiian Islands

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The ship has been alongside for repairs and leave since November, 2009. The ship shakedown cruise is scheduled to provide an opportunity for the ship to get underway...

  4. Solar sail trajectory design in the Earth-Moon circular restricted three body problem

    Science.gov (United States)

    Das, Ashwati

    The quest to explore the Moon has helped resolve scientific questions, has spurred leaps in technology development, and has revealed Earth's celestial companion to be a gateway to other destinations. With a renewed focus on returning to the Moon in this decade, alternatives to chemical propulsion systems are becoming attractive methods to efficiently use scarce resources and support extended mission durations. Thus, an investigation is conducted to develop a general framework, that facilitates propellant-free Earth-Moon transfers by exploiting sail dynamics in combination with advantageous transfer options offered in the Earth-Moon circular restricted multi-body dynamical model. Both periodic orbits in the vicinity of the Earth-Moon libration points, and lunar-centric long-term capture orbits are incorporated as target destinations to demonstrate the applicability of the general framework to varied design scanarios, each incorporating a variety of complexities and challenges. The transfers are comprised of three phases - a spiral Earth escape, a transit period, and, finally, the capture into a desirable orbit in the vicinity of the Moon. The Earth-escape phase consists of spiral trajectories constructed using three different sail steering strategies - locally optimal, on/off and velocity tangent. In the case of the Earth-libration point transfers, naturally occurring flow structures (e.g., invariant manifolds) arising from the mutual gravitational interaction of the Earth and Moon are exploited to link an Earth departure spiral with a destination orbit. In contrast, sail steering alone is employed to establish a link between the Earth-escape phase and capture orbits about the Moon due to a lack of applicable natural structures for the required connection. Metrics associated with the transfers including flight-time and the influence of operational constraints, such as occultation events, are investigated to determine the available capabilities for Earth

  5. Reliability Based Ship Structural Design

    DEFF Research Database (Denmark)

    Dogliani, M.; Østergaard, C.; Parmentier, G.

    1996-01-01

    This paper deals with the development of different methods that allow the reliability-based design of ship structures to be transferred from the area of research to the systematic application in current design. It summarises the achievements of a three-year collaborative research project dealing...... with developments of models of load effects and of structural collapse adopted in reliability formulations which aim at calibrating partial safety factors for ship structural design. New probabilistic models of still-water load effects are developed both for tankers and for containerships. New results are presented...... structure of several tankers and containerships. The results of the reliability analysis were the basis for the definition of a target safety level which was used to asses the partial safety factors suitable for in a new design rules format to be adopted in modern ship structural design. Finally...

  6. Design of Crashworthy Ship Strucures

    DEFF Research Database (Denmark)

    Toernqvist, Rikard

    2003-01-01

    The main purpose of the project has been to develop a rational procedure for designing new crashworthy side structures for those ship types where it could be expected that a substantial improvement of the crashworthiness and the related safety could be achieved by careful consideration of the str......The main purpose of the project has been to develop a rational procedure for designing new crashworthy side structures for those ship types where it could be expected that a substantial improvement of the crashworthiness and the related safety could be achieved by careful consideration...... in collision and grounding analysis is the prediction of the onset of fracture and crack propagation in the shell plating. In simulations of accidental loading on ships it is crucial that fracture is determined correctly, as it will influence the global deformation mode and the amount of damage to the hull...

  7. On Grounding of Fast Ships

    DEFF Research Database (Denmark)

    Simonsen, Bo Cerup; Pedersen, Preben Terndrup

    1997-01-01

    The paper deals with analysis of grounding of high-speed crafts. It is the purpose to present a comprehensive mathematical model for calculation of the overall dynamic ship response during grounding. This procedure is applied to derive the motions, the time varying sectional forces and the local...... loads during grounding on plane, sloping, sandy bottoms for six different designs of fast monohull ships made from steel, aluminium or GRP sandwich materials. The results show that the effect of the hull flexibility is to reduce the overall dynamic sectional loads on the hull girder. The considered...... numerical examples also indicate that, even with impact speeds of 40 knots against a 1:10 sloping bottom, the global strength of the hull girder is not exceeded by the grounding induced loads.For the local deformation of high-speed ship hulls at the point of contact with the ground, the paper presents...

  8. Fuel exchanger for nuclear ships

    International Nuclear Information System (INIS)

    Suda, Koji; Kanbara, Takahisa; Watanabe, Masaharu.

    1984-01-01

    Purpose: To prevent enviromental contamination landing radioactive materials from the inside of a ship. Constitution: A provisional cabin having a shape covering a reactor hatch and a hatch cover is disposed on the upper deck of a ship body. A ceiling shutter is disposed to the cabin. A protection cylinder having a shutter and a filter fan is attached on the cabin. Materials to be discharged out of the ship are transported to a fuel exchange tower on land by using a crane while being contained in the protection cylinder with the shutter being closed. The protection cylinder is connected by means of a wire rope to a loop-wheel machine which disposed on the trolly of a crane. While the bellows through which the suspending wire for the discharged products passes is perforated, since the inside of the cylinder is depressurized by a filter fan, there is no air leakage through the perforation to the outside. (Ikeda, J.)

  9. Fuel exchanger for nuclear ships

    Energy Technology Data Exchange (ETDEWEB)

    Suda, Koji; Kanbara, Takahisa; Watanabe, Masaharu

    1984-11-29

    To prevent enviromental contamination by radioactive materials from the inside of a ship a provisional cabin having a shape covering a reactor hatch and a hatch cover is disposed on the upper deck of a ship body. A ceiling shutter is disposed to the cabin. A protection cylinder having a shutter and a filter fan is attached on the cabin. Materials to be discharged out of the ship are transported to a fuel exchange tower on land by using a crane while being contained in the protection cylinder with the shutter being closed. The protection cylinder is connected by means of a wire rope to a loop-wheel machine which is disposed on the trolly of a crane. While the bellows through which the suspending wire for the discharged products passes is perforated, since the inside of the cylinder is depressurized by a filter fan, there is no air leakage through the perforation to the outside.

  10. Wind Forces on Container Ships

    DEFF Research Database (Denmark)

    Andersen, Ingrid Marie Vincent

    2012-01-01

    An investigation of the wind forces acting on a 9,000+ TEU container ship has been carried out through a series of wind tunnel tests. It was investigated how the wind forces depend on the container configuration on the deck using a 1:450 scale model and a series of appropriate container...... are presented as nondimensional coefficients. It is concluded, that the measured forces and moment depend on the container configuration on deck, and the results may provide a general idea of how the magnitude of the wind forces is affected by a given container stacking configuration on a similar container ship....

  11. Quality management in shipping companies

    Directory of Open Access Journals (Sweden)

    Đergović Dragana M.

    2017-01-01

    Full Text Available As international business becomes more competitive, companies are finding that they need to work more effectively to stay in business. Quality assurance has become very important to the majority of production and service companies with international activity. Shipping companies were also required to implement a quality management system. The huge importance of safety in maritime transport operations resulted in the International Safety Management Code (ISM Code by the International Maritime Organization. The general management system principles embodied by the maritime ISM Code and generics ISO standards, have enabled their complementary application in establishing a quality management system in shipping companies, within a safety management system as its subset.

  12. Design and Characterization of a Small-Scale Solar Sail Prototype by Integrating NiTi SMA and Carbon Fibre Composite

    Directory of Open Access Journals (Sweden)

    Girolamo Costanza

    2017-01-01

    Full Text Available Solar sails are propellantless systems where the propulsive force is given by the momentum exchange of reflecting photons. In this study, a self-deploying system based on NiTi shape memory wires and sheets has been designed and manufactured. A small-scale prototype of solar sail with carbon fibre loom has been developed. Different configurations have been tested to optimize material and structure design of the small-scale solar sail. In particular the attention has been focused on the surface/weight ratio and the deployment of the solar sail. By reducing weight and enlarging the surface, it is possible to obtain high values of characteristic acceleration that is one of the main parameters for a successful use of the solar sail as propulsion system. Thanks to the use of shape memory alloys for self-actuation of the system, complexity of the structure itself decreases. Moreover, sail deployment is simpler.

  13. Initial Results from the STEM Student Experiences Aboard Ships (STEMSEAS) Program

    Science.gov (United States)

    Lewis, J. C.; Cooper, S. K.; Thomson, K.; Rabin, B.; Alberts, J.

    2016-12-01

    The Science Technology Engineering and Math Student Experiences Aboard Ships (STEMSEAS) program was created as a response to NSF's call (through GEOPATHS) for improving undergraduate STEM education and enhancing diversity in the geosciences. It takes advantage of unused berths on UNOLS ships during transits between expeditions. During its 2016 pilot year - which consisted of three transits on three different research vessels in different parts of the country, each with a slightly different focus - the program has gained significant insights into how best to create and structure these opportunities and create impact on individual students. A call for applications resulted in nearly 900 applicants for 30 available spots. Of these applicants, 32% are from minority groups underrepresented in the geosciences (Black, Hispanic, or American Indian) and 20% attend community colleges. The program was able to sail socioeconomically diverse cohorts and include women, veterans, and students with disabilities and from two- and four-year colleges. Twenty-three are underrepresented minorities, 6 attend community colleges, 5 attend an HBCU or tribal college, and many are at HSIs or other MSIs. While longer term impact assessment will have to wait, initial results and 6-month tracking for the first cohort indicate that these kinds of relatively short but intense experiences can indeed achieve significant impacts on students' perception of the geosciences, in their understanding of STEM career opportunities, their desire to work in a geoscience lab setting, and to incorporate geosciences into non-STEM careers. Insights were also gained into the successful makeup of mentor/leader groups, factors to consider in student selection, necessary pre- and post-cruise logistics management, follow-up activities, structure of activities during daily life at sea, increasing student networks and access to mentorships, and leveraging of pre-existing resources and ship-based opportunities

  14. 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.

  15. 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.

  16. MODEL CORRELATION STUDY OF A RETRACTABLE BOOM FOR A SOLAR SAIL SPACECRAFT

    Science.gov (United States)

    Adetona, O.; Keel, L. H.; Oakley, J. D.; Kappus, K.; Whorton, M. S.; Kim, Y. K.; Rakpczy, J. M.

    2005-01-01

    To realize design concepts, predict dynamic behavior and develop appropriate control strategies for high performance operation of a solar-sail spacecraft, we developed a simple analytical model that represents dynamic behavior of spacecraft with various sizes. Since motion of the vehicle is dominated by retractable booms that support the structure, our study concentrates on developing and validating a dynamic model of a long retractable boom. Extensive tests with various configurations were conducted for the 30 Meter, light-weight, retractable, lattice boom at NASA MSFC that is structurally and dynamically similar to those of a solar-sail spacecraft currently under construction. Experimental data were then compared with the corresponding response of the analytical model. Though mixed results were obtained, the analytical model emulates several key characteristics of the boom. The paper concludes with a detailed discussion of issues observed during the study.

  17. Angular velocity determination of spinning solar sails using only a sun sensor

    Directory of Open Access Journals (Sweden)

    Kun Zhai

    2017-02-01

    Full Text Available The direction of the sun is the easiest and most reliable observation vector for a solar sail running in deep space exploration. This paper presents a new method using only raw measurements of the sun direction vector to estimate angular velocity for a spinning solar sail. In cases with a constant spin angular velocity, the estimation equation is formed based on the kinematic model for the apparent motion of the sun direction vector; the least-squares solution is then easily calculated. A performance criterion is defined and used to analyze estimation accuracy. In cases with a variable spin angular velocity, the estimation equation is developed based on the kinematic model for the apparent motion of the sun direction vector and the attitude dynamics equation. Simulation results show that the proposed method can quickly yield high-precision angular velocity estimates that are insensitive to certain measurement noises and modeling errors.

  18. Thrust evaluation of magneto plasma sail that obtains an electromagnetic thrust from the solar wind

    International Nuclear Information System (INIS)

    Kajimura, Yoshihiro; Funaki, Ikkoh; Usui, Hideyuki; Yamakawa, Hiroshi

    2011-01-01

    Magneto Plasma Sail (MPS) is a propulsion system used in space, which generates its force by the interaction between the solar wind and an inflated magnetic field via a plasma injection. The quantitative evaluation of the thrust increment generated by injecting a plasma jet with a β in less than unity was conducted by three-dimensional hybrid particle-in-cell (PIC) simulations in an ion inertia scale. The injected plasma β in is 0.02 and the ratio of Larmor radius of injected ion to the representative length of the magnetic field is 0.5 at the injection point. In this situation, the obtained thrust of the MPS is 1.6 mN compared with the 0.2 mN of the thrust obtained by the pure magnetic sail since the induced current region on magnetosphere expanded by the magnetic inflation. (author)

  19. Laser-light sailing and non-stationary power stations applied to robotic star probes

    International Nuclear Information System (INIS)

    Matloff, Gregory L.

    2000-01-01

    The light sail has emerged as a leading contender to propel extrasolar expeditions. Because solar-sail performance is limited by the inverse-square law, one-way expeditions to other stars requiring voyage durations of a few centuries or less may be propelled by radiation pressure from a laser beam originating from a location closer to the Sun than the space probe. Maintaining a stationary laser power station in position between Sun and spacecraft for years or decades presents many technical challenges. This paper presents a variation on the laser power station that may be simpler to implement, in which the Sun-pumped laser power station follows the spacecraft on a parabolic or slightly hyperbolic trajectory

  20. 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.

  1. Helicopter-Ship Qualification Testing

    NARCIS (Netherlands)

    Hoencamp, A.

    2015-01-01

    The goal of this research project is to develop a novel test methodology which can be used for optimizing cost and time efficiency of helicopter-ship qualification testing without reducing safety. For this purpose, the so-called “SHOL-X” test methodology has been established, which includes the

  2. Container for shipping dangerous material

    International Nuclear Information System (INIS)

    Blum, P.T.

    1987-01-01

    This container for shipping dangerous material is made by a cylindrical casing of austenitic stainless steel with rounded ends and walls of uniform thickness with welded joins, a tubular metal shock absorber fixed over each end of the casing, removable lugs fixed to the casing, optionally retainers for the material within the casing [fr

  3. Modeling of Ship Propulsion Performance

    DEFF Research Database (Denmark)

    Pedersen, Benjamin Pjedsted; Larsen, Jan

    2009-01-01

    Full scale measurements of the propulsion power, ship speed, wind speed and direction, sea and air temperature, from four different loading conditions has been used to train a neural network for prediction of propulsion power. The network was able to predict the propulsion power with accuracy...

  4. Lifecycle Readiness and Ship Deployment

    Science.gov (United States)

    2013-06-01

    incidence of vomiting reported on military transport ships traveling across the Atlantic to vary from 8.5% to 22.1% on three crossings. Bruner (1955...Butterworth (pp. 455-471). Bruner , J. M. (1955). Seasickness in a destroyer escort squadron. United States Armed Forces Medical Journal, 6(4), 469-490

  5. Rudder roll stabilization for ships

    NARCIS (Netherlands)

    van Amerongen, J.; van der Klugt, P.G.M.; van Nauta lemke, H.R.

    1990-01-01

    This paper describes the design of an autopilot for rudder roll stabilization for ships. This autopilot uses the rudder not only for course keeping but also for reduction of the roll. The system has a series of properties which make the controller design far from straightforward: the process has

  6. Designing Indonesian Liner Shipping Network

    Directory of Open Access Journals (Sweden)

    Armand Omar Moeis

    2017-06-01

    Full Text Available As the largest archipelago nation in the world, Indonesia’s logistics system has not shown excellence according to the parameters of logistics performance index and based on logistics costs percentages from overall GDP. This is due to the imbalances of trading on the western and eastern regions in Indonesia, which impacts the transportation systems costs to and from the eastern regions. Therefore, it is imperative to improve the competitiveness of Indonesian maritime logistics through maritime logistics network design. This research will focus on three levels of decision making in logistics network design, which include type of ships in the strategic level, shipping routes in the tactical level, and container allocation in the operational level with implementing butterfly routes in Indonesia’s logistics networking problems. Furthermore, this research will analyze the impact of Pendulum Nusantara and Sea Toll routes against the company profits and percentages of containers shipped. This research will also foresee how demand uncertainties and multi-period planning should affect decision making in designing the Indonesian Liner Shipping Network.

  7. Legal risk management in shipping

    DEFF Research Database (Denmark)

    Siig, Kristina

    The book discusses the most typical legal challenges met in the chartering, broker, agent or port management part of the shipping industry. It discusses these issues in both English and Scandinavian law and gives indications on how to best ensure your legal risk management in these parts...

  8. Further development and performance evaluation of the autonomous sailing boat Maribot Vane

    OpenAIRE

    Dhomé, Ulysse

    2018-01-01

    This paper describes the ongoing development of Maribot Vane, an autonomous sailing vessel at the Maritime Robotics Laboratory of KTH, the Royal Institute of Technology, Stockholm. There is an ac-celerating need for ocean sensing where autonomous vehicles can play a key role in assisting scientists with environmental monitoring and collecting oceanographic data. The purpose of Maribot Vane is to offer a sus-tainable alternative for these autonomous missions by using wind and an energy efficie...

  9. SAIL Panama Canal Zone Project 2008 : Biological Survey of Panama (1910-1912)

    OpenAIRE

    DeHart, Liz; Haas, Stephanie C.; Walton, Jennifer; Heil, Kathy

    2009-01-01

    During the 18th Annual 2008 SAIL meeting at the Smithsonian Tropical Research Institute in Panama, a suggestion was made for the need to digitize and make available through the Aquatic Commons some of the early documents related to the U.S. biological survey of Panama from 1910 to 1912. With SAIL’s endeavor, a new digital project was born and this presentation describes its process, beginning to final product. The main source consulted for determining copyright clear publications was: ...

  10. 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.

  11. 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.

  12. Low-cost gossamer systems for solar sailing and spacecraft deorbiting applications.

    OpenAIRE

    Fernandez, Juan M.

    2015-01-01

    Nowadays, a technology demonstrator platform popular amongst the research community given their relatively low cost and short development time are cubesats. Nevertheless, cubesats are by definition nano-satellites of small volume and mass, and therefore, they traditionally only allowed very limited sizes of any expandable structure onboard with final deployed areas in the order of a few square meters. This conflicts with the large areas required for efficient solar sails, making the demonstra...

  13. Sleep restriction and degraded reaction-time performance in Figaro solo sailing races.

    Science.gov (United States)

    Hurdiel, Rémy; Van Dongen, Hans P A; Aron, Christophe; McCauley, Peter; Jacolot, Laure; Theunynck, Denis

    2014-01-01

    In solo offshore sailing races like those of the Solitaire du Figaro, sleep must be obtained in multiple short bouts to maintain competitive performance and safety. Little is known about the amount of sleep restriction experienced at sea and the effects that fatigue from sleep loss have on sailors' performance. Therefore, we assessed sleep in sailors of yachts in the Figaro 2 Beneteau class during races and compared response times on a serial simple reaction-time test before and after races. Twelve men (professional sailors) recorded their sleep and measured their response times during one of the three single-handed races of 150, 300 and 350 nautical miles (nominally 24-50 h in duration). Total estimated sleep duration at sea indicated considerable sleep insufficiency. Response times were slower after races than before. The results suggest that professional sailors incur severe sleep loss and demonstrate marked performance impairment when competing in one- to two-day solo sailing races. Competitive performance could be improved by actively managing sleep during solo offshore sailing races.

  14. Ecological dynamics of continuous and categorical decision-making: the regatta start in sailing.

    Science.gov (United States)

    Araújo, Duarte; Davids, Keith; Diniz, Ana; Rocha, Luis; Santos, João Coelho; Dias, Gonçalo; Fernandes, Orlando

    2015-01-01

    Ecological dynamics of decision-making in the sport of sailing exemplifies emergent, conditionally coupled, co-adaptive behaviours. In this study, observation of the coupling dynamics of paired boats during competitive sailing showed that decision-making can be modelled as a self-sustained, co-adapting system of informationally coupled oscillators (boats). Bytracing the spatial-temporal displacements of the boats, time series analyses (autocorrelations, periodograms and running correlations) revealed that trajectories of match racing boats are coupled more than 88% of the time during a pre-start race, via continuous, competing co-adaptions between boats. Results showed that both the continuously selected trajectories of the sailors (12 years of age) and their categorical starting point locations were examples of emergent decisions. In this dynamical conception of decision-making behaviours, strategic positioning (categorical) and continuous displacement of a boat over the course in match-race sailing emerged as a function of interacting task, personal and environmental constraints. Results suggest how key interacting constraints could be manipulated in practice to enhance sailors' perceptual attunement to them in competition.

  15. 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

  16. 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.

  17. 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.

  18. THE ASSESSMENT OF DIFFICULTY OF YACHT SAILING CLASSES AND STUDENTS' GLOBAL SELF-ESTEEM

    Directory of Open Access Journals (Sweden)

    Anna Romanowska-Tolloczko

    2015-06-01

    Full Text Available Purpose: determination of relationship between the level of students’ global self-esteem and their perception of the degree of difficulty sailing yacht classes. Material and methods: Study consisted of 178 students of University School of Physical Education in Wrocław. The study used two tools: Polish adaptation of SES M. Rosenberg Self-Esteem Scale and a questionnaire designed by the authors of the study. Results: men were characterized by a higher self-esteem than women. Distribution of the results obtained by women was closer to a normal distribution, but it was not completely compatible with it. The relationship was noted between the level of global self-esteem of the students and their perception of the degree of difficulty of the course. People with higher self-esteem assessed the knowledge and skills of sailing as easier. For people with lower levels of self-esteem sailing it was a more difficult. Conclusions: self-acceptance and self-esteem have a substantial impact on goal setting and the perception and taking various tasks. It is therefore important to help young people to build adequate self-esteem and positive self-image, because faith in its own strength and capabilities is a key element in achieving success in every area of life.

  19. Logistical Analysis of the Littoral Combat Ship

    National Research Council Canada - National Science Library

    Rudko, David

    2003-01-01

    The purpose of the Littoral Combat Ship (LCS) is to provide the Navy with an affordable, small, multi-mission ship capable of independent, interdependent, and integrated operations inside the littorals...

  20. Facts about Noroviruses on Cruise Ships

    Science.gov (United States)

    ... Cruise Tips for Healthy Cruising Related Resources Cruise Ship Inspection Scores & Information Inspection Scores Cruise Line Directory Green ... 800-CDC-INFO ( 1-800-232-4636 ). Cruise Ship Inspection Scores & Information Inspection Scores Cruise Line Directory Green ...

  1. New Zealand code for nuclear powered shipping

    International Nuclear Information System (INIS)

    1976-06-01

    This report recommends guidelines for the safety precautions and procedures to be implemented when New Zealand ports and approaches are used by nuclear powered merchant ships and nuclear powered naval ships

  2. International climate policy : consequences for shipping

    OpenAIRE

    Mæstad, Ottar; Evensen, Annika Jaersen; Mathiesen, Lars; Olsen, Kristian

    2000-01-01

    This report summarises the main results from the project Norwegian and international climate policy consequences for shipping. The aim of the project has been to shed light on how climate policies might affect shipping, both from the cost side and from the demand side. The project has been divided into three sub-projects, investigating the consequences of climate policies for 1. Optimal shipping operations and management 2. The competitiveness of shipping relative to land transport 3. The tra...

  3. Note from the radioprotection group's shipping service

    CERN Multimedia

    2006-01-01

    The service for the import/export of radioactive materials reminds you that shipping requests for potentially radioactive materials must be made via the EDH request form by ticking the box 'radioactive material'. All the necessary information is given on the web site: http://cern.ch/service-rp-shipping Requests not complying with the above procedure will not be taken into account. Radioactive Shipping Service http://cern.ch/service-rp-shipping Tel. 73171 Fax: 69200

  4. Real-Time Simulation of Ship-Structure and Ship-Ship Interaction

    DEFF Research Database (Denmark)

    Lindberg, Ole; Glimberg, Stefan Lemvig; Bingham, Harry B.

    2013-01-01

    , because it is simple, easy to implement and computationally efficient. Multiple many-core graphical processing units (GPUs) are used for parallel execution and the model is implemented using a combination of C/C++, CUDA and MPI. Two ship hydrodynamic cases are presented: Kriso Container Carrier at steady...

  5. Ship-to-Ship Radiocommunication Trial by Using Wireless LAN

    Directory of Open Access Journals (Sweden)

    Yasuyuki Niwa

    2015-12-01

    In a former field radiocommunication trial, omni-directional antennas were used and a few hundred kbps throughput between two ships was measured, which was not enough for our research target (over 1Mbps. In order to get faster throughput, a field radiocommunication trial was carried out again with a few types of directional antennas and RSSI (Received Signal Strength Indication and the throughput between two ships was measured simultaneously. As a result, multi-path (2-path model affected by the reflection of the sea surface was confirmed and also the characteristics of the directional antennas such as half-power angle were confirmed, but the measured throughput was fast enough to meet our expectation.

  6. Accidents on ships in the Danish International Ship register

    DEFF Research Database (Denmark)

    Ádám, Balázs; Rasmussen, Hanna Barbara

    to report accidents causing at least one day off work beyond the day of accident but the first source contains several accidents not fulfilling this criterion, too. Radio Medical is an independent service where all Danish ships may seek medical advice. The data sets were merged by identification number...... of our study is to describe trend of accidents and their contributing factors, with special focus on nationality, occurring in ships under Danish flag in the period 2010-2012. The study used two independent data sources, the Danish Maritime Authority and the Danish Radio Medical. It is mandatory...... to create a single database that has been studied by descriptive statistics and regression analysis. Findings show a stabilised number of accidents in the analysed period. The occurrence of accidents is influenced by nationality. There is a higher frequency of reported injuries found among Danish and other...

  7. 19 CFR 4.69 - Shipping articles.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Shipping articles. 4.69 Section 4.69 Customs... VESSELS IN FOREIGN AND DOMESTIC TRADES Foreign Clearances § 4.69 Shipping articles. No vessel of the U.S... officer, of the shipping articles agreements, including any seaman's allotment agreement, required by 46 U...

  8. 15 CFR 750.11 - Shipping tolerances.

    Science.gov (United States)

    2010-01-01

    ... in the ECCN applicable to your item reads “ $ value” or “in $ value”, there is no shipping tolerance... is no shipping tolerance with respect to the number of units. However, the value of all of your... shipping tolerance on this license because the items are controlled by an ECCN where “$ value” is the...

  9. 29 CFR 1915.162 - Ship's boilers.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Ship's boilers. 1915.162 Section 1915.162 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) OCCUPATIONAL SAFETY AND HEALTH STANDARDS FOR SHIPYARD EMPLOYMENT Ship's Machinery and Piping Systems § 1915.162 Ship's boilers. (a) Before...

  10. 27 CFR 44.187 - Shipping containers.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2010-04-01 2010-04-01 false Shipping containers. 44... Shipping containers. Each shipping case, crate, or other container in which tobacco products, or cigarette... same containers in which they were received from the factory. (72 Stat. 1418, as amended; 26 U.S.C...

  11. 27 CFR 44.254 - Shipping containers.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2010-04-01 2010-04-01 false Shipping containers. 44.254 Section 44.254 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU... Requirements § 44.254 Shipping containers. Each shipping case, crate, or other container, in which cigars are...

  12. 49 CFR 176.24 - Shipping papers.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Shipping papers. 176.24 Section 176.24... Requirements § 176.24 Shipping papers. (a) A person may not accept a hazardous material for transportation or transport a hazardous material by vessel unless that person has received a shipping paper prepared in...

  13. 49 CFR 177.817 - Shipping papers.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Shipping papers. 177.817 Section 177.817... Information and Regulations § 177.817 Shipping papers. (a) General requirements. A person may not accept a... received a shipping paper prepared in accordance with part 172 of this subchapter or the material is...

  14. 49 CFR 174.24 - Shipping papers.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Shipping papers. 174.24 Section 174.24... Requirements § 174.24 Shipping papers. (a) A person may not accept a hazardous material for transportation or transport a hazardous material by rail unless that person receives a shipping paper prepared in accordance...

  15. Improving the competitiveness of green ship recycling

    NARCIS (Netherlands)

    Jain, K.P.

    2017-01-01

    The end of life of a ship is determined by its owner on the basis of various commercial and technical factors. Once decided to scrap a ship, almost all end-of-life (EOL) ships are sold to recycling yards for dismantling; except for a few which are converted into museums, hotels, storage, and

  16. 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

  17. Using new technology to keep oil shipping risks in check

    International Nuclear Information System (INIS)

    Niini, M.

    2001-01-01

    The opening of a new crude of terminal at Primorsk on the Karelian Isthmus north of St. Petersburg at the beginning of 2002 win bring a new set of major environmental risks to the waters of the Gulf of Finland Kvaerner Masa-Yards has developed new technology ideally suited to ships using the new terminal. The company's double-hulled, 'double-acting tanker' concept and 'oblique icebreaker' represent a new generation of cost-effective solutions. The highly regulated nature of the domestic oil market in Russia makes exports an attractive option for local producers, as does the current high level of world crude prices. Oil production in Russia in 2000 increased by 6% compared to 1999, to 323 million tonnes, and exports rose by over 15%, to 143 million tonnes. Getting crude to the customer is becoming increasingly difficult, however. The capacity of the Bosporous to handle shipments from the Caspian has probably reached its current ceiling, of some 50 million t/a. Further north, a number of political and economic tensions surround Russia's pipelines through Latvia and Lithuania; and some 20 million t/a are already being exported by rail through Tallinn. Part of Russia's solution to this ongoing problem has been to launch construction of a new, green field terminal at Primorsk on the Karelian Isthmus between St. Petersburg and the Finnish-Russian border. The first stage of the terminal, capable of handling 12 million t/a, is expected to be completed by the beginning of 2002; the terminal's second stage, planned for completion later, will have a capacity of 40 million t/a. If the project comes to full fruition, the result will be one supertanker a day sailing down the Gulf of Finland past Helsinki. The Primorsk terminal brings with it a new set of risks. Central to these is the fact that the route to the terminal passes through shallow water and winds be- tween a number of islands in the nearby archipelago. Another major risk is associated with the difficult ice

  18. Intelligent Prediction of Ship Maneuvering

    Directory of Open Access Journals (Sweden)

    Miroslaw Lacki

    2016-09-01

    Full Text Available In this paper the author presents an idea of the intelligent ship maneuvering prediction system with the usage of neuroevolution. This may be also be seen as the ship handling system that simulates a learning process of an autonomous control unit, created with artificial neural network. The control unit observes input signals and calculates the values of required parameters of the vessel maneuvering in confined waters. In neuroevolution such units are treated as individuals in population of artificial neural networks, which through environmental sensing and evolutionary algorithms learn to perform given task efficiently. The main task of the system is to learn continuously and predict the values of a navigational parameters of the vessel after certain amount of time, regarding an influence of its environment. The result of a prediction may occur as a warning to navigator to aware him about incoming threat.

  19. Competitive Liner Shipping Network Design

    DEFF Research Database (Denmark)

    Karsten, Christian Vad

    .The contributions of this thesis cover modeling, methodology, and applications.The developed methods address operational (cargo routing), tactical (speed optimization and service selection), and strategic (network design) planning problems faced by liner shipping companies. Ultimately, the proposed methods help...... take the container transportation times that can be realized in the network nor the number of transshipments into consideration. This is mainly because the optimization problem is based on other transportation networks where these constraints are not decisive to the quality of the network. Furthermore......, the problem in itself is challenging to optimize due to its size and complexity. However, the field has seen crucial progress and is mature to include handling of competitiveness in the actual design of the network.As a liner shipping network is an organic entity, which is constantly changed to reflect...

  20. Evaluation of the Service Performance of Ships

    DEFF Research Database (Denmark)

    Andersen, Poul; Borrod, Anne-Sophie; Blanchot, Hervé

    2005-01-01

    A simple method has been established for the evaluation of the service performance of ships. Input data are easily collected daily on board and transformed to a well-defined condition that makes possible the comparison between ships, for instance, sister ships, and between different time periods...... of voyages for the same ship. The procedure has been applied to two ships that are identical, with the exception that one has a conventional propeller, whereas the other one is fitted with a high-efficiency propeller of the KAPPEL type. The results are obtained from a period of 2 years steaming for both...