WorldWideScience

Sample records for big wheel triumph

  1. The big wheels of ATLAS

    CERN Multimedia

    2006-01-01

    The ATLAS cavern is filling up at an impressive rate. The installation of the first of the big wheels of the muon spectrometer, a thin gap chamber (TGC) wheel, was completed in September. The muon spectrometer will include four big moving wheels at each end, each measuring 25 metres in diameter. Of the eight wheels in total, six will be composed of thin gap chambers for the muon trigger system and the other two will consist of monitored drift tubes (MDTs) to measure the position of the muons (see Bulletin No. 13/2006). The installation of the 688 muon chambers in the barrel is progressing well, with three-quarters of them already installed between the coils of the toroid magnet.

  2. Milestone reached for the Big Wheels of the Muon Spectrometer

    CERN Multimedia

    Sandro Palestini

    The assembly and integration of the Big Wheels sectors of the Muon Spectrometer is reaching its conclusion, with only a few sectors of Wheel TGC-A-3 remaining on the assembly stations in building 180. The six trigger chambers (TGCs) wheels and two precision chambers wheels (MDTs) contain in total 104 sectors, which were assembled, equipped with detectors and fully tested over a period of two years. The few remaining Big Wheel sectors still stored in building 180 Most of the sectors left building 180 over the last twelve months, and form the six Wheels currently installed in the ATLAS detector. The remaining two will be installed before the end of the summer. The commitment of the personnel from the many teams who contributed to different parts of the project was essential to its success. In particular, teams coming from countries of different traditions and languages, such as China, Israel, Japan, Pakistan, Russia and USA contributed and collaborated very effectively to the timely completion of the p...

  3. Installation of the first of the big wheels of the ATLAS muon spectrometer, a thin gap chamber (TGC) wheel

    CERN Multimedia

    Claudia Marcelloni

    2006-01-01

    The muon spectrometer will include four big moving wheels at each end, each measuring 25 metres in diameter. Of the eight wheels in total, six will be composed of thin gap chambers for the muon trigger system and the other two will consist of monitored drift tubes (MDTs) to measure the position of the muons

  4. Wheel Diameter and Speedometer Reading

    Science.gov (United States)

    Murray, Clifton

    2010-01-01

    Most introductory physics students have seen vehicles with nonstandard wheel diameters; some may themselves drive "low-rider" cars or "big-wheel" pickup trucks. But how does changing wheel diameter affect speedometer readout for a given speed? Deriving the answer can be followed readily by students who have been introduced to rotation, and it…

  5. Transfer, refurbishment and commissioning of a big bucket wheel excavator from the Czech Republic to Germany; Umsetzung, Modernisierung und Inbetriebnahme eines Grossschaufelradbaggers von Tschechien nach Deutschland

    Energy Technology Data Exchange (ETDEWEB)

    Gerlach, T. [TAKRAF GmbH, Lauchhammer (Germany); Werner, U. [MIBRAG GmbH, Technische Dienste - Maschinentechnik, Theissen (Germany)

    2007-03-15

    The Profen mine of the Mitteldeutsche Braunkohlengesellschaft mbh (MIBRAG) will be gradually transferred from Profen-South to Schwerzau mining field within the next few years. In order to compensate for the worse geological conditions it will be necessary to reduce unit costs at Schwerzau. Several variants of technical equipment were reviewed with respect to the large mine equipment at the new mining field. As a result, it seemed to be the most favorable solution to transfer and modernize a SRs 2000+VR bucket wheel excavator. In 2003 the transfer was started, in June 2006 the bucket wheel excavator with loading unit was accepted at the Schwerzau mining field. (orig.)

  6. Saving the Dust Bowl: "Big Hugh" Bennett's Triumph over Tragedy

    Science.gov (United States)

    Smith, Rebecca

    2007-01-01

    In the 1930s, years of injudicious cultivation had devastated 100 million acres of Kansas, Oklahoma, Texas, Colorado, and New Mexico. This was the Dust Bowl, and it exposed a problem that had silently plagued American agriculture for centuries--soil erosion. Farmers, scientists, and the government alike considered it trivial until Hugh Hammond…

  7. A prototype of one of the eight sections that will form one of the big-wheels of the ATLAS muon spectrometer has been installed in building 887 at Prévessin . Over 40 institutes in 11 countries are involved in the construction of the ATLAS muon spectrometer.

    CERN Multimedia

    Patrice Loïez

    2001-01-01

    A prototype of one of the eight sections that will form one of the big-wheels of the ATLAS muon spectrometer has been installed in building 887 at Prévessin . Over 40 institutes in 11 countries are involved in the construction of the ATLAS muon spectrometer.

  8. Gifts and exchanges problems, frustrations, and triumphs

    CERN Document Server

    Katz, Linda S; Denning, Catherine

    2013-01-01

    This important book explores the many questions challenging librarians who work with gifts and exchanges (G&E) as part of their daily responsibilities. Too often, because of shrinking library budgets, library gifts are considered burdensome and unprofitable drains on both financial and personnel resources. However, Gifts and Exchanges: Problems, Frustrations, . . . and Triumphs gives you solutions that will allow you to embrace your library's gifts as rewards. In this book, you will discover the latest ways of disposing unwanted materials, planning and holding book sales and auctions, and oper

  9. Word wheels

    CERN Document Server

    Clark, Kathryn

    2013-01-01

    Targeting the specific problems learners have with language structure, these multi-sensory exercises appeal to all age groups including adults. Exercises use sight, sound and touch and are also suitable for English as an Additional Lanaguage and Basic Skills students.Word Wheels includes off-the-shelf resources including lesson plans and photocopiable worksheets, an interactive CD with practice exercises, and support material for the busy teacher or non-specialist staff, as well as homework activities.

  10. Oedipus and the sphinx: triumph and catastrophe.

    Science.gov (United States)

    Palombo, S R

    1994-01-01

    The downfall of Oedipus in Sophocles' most famous play, Oedipus Tyrannus, is the reversal of his triumphant entry into the city of Thebes 17 years earlier. The oracle at Delphi has told the Thebans that the plague will end only when the murderer of Laius is identified and punished. The unconscious collusion between Oedipus and the Thebans to ignore the unsolved murder breaks down. Told by Teiresias that he is the culprit, Oedipus begins a desperate effort to find evidence to refute this accusation. When other witnesses come forward, his cause is lost. The effect of Oedipus's collusive interaction with the Thebans is balanced in Sophocles' account by the story of the riddle of the Sphinx. The Sphinx is a goddess of discontinuity. She represents the unconscious forces at work both in Oedipus's personal fantasies and in the collective fantasies of the Thebans. The tragedy results from the interaction of these fantasies in the government of the polis. Sophocles' play thus exemplifies the intricate intertwining of the child's innate wishes and the reaction they evoke from the environment during the oedipal period. The neurotic patient's illusion of sexual triumph over his or her father or mother as a child can be best understood through the interaction of these factors. PMID:8040558

  11. Running Wheel for Earthworms

    OpenAIRE

    Wilson, W. Jeffrey; Johnson, Brandon A.

    2016-01-01

    We describe the construction and use of a running wheel responsive to the movement of the earthworm. The wheel employs readily available, inexpensive components and is easily constructed. Movement of the wheel can be monitored visually or via standard behavioral laboratory computer interfaces. Examples of data are presented, and possibilities for use in the teaching classroom are discussed.

  12. Reinventing the Wheel

    Science.gov (United States)

    Kim, Mihyeon; Bland, Lori C.; Chandler, Kimberley

    2009-01-01

    "The Wheel of Scientific Investigation and Reasoning" (Kramer 1987; Paul and Binker 1992) is a graphic representation of the scientific investigative process. The scientific process is depicted in a wheel rather than in a list because "the process of scientific inquiry can begin from any stage, and that stage may be revisited as often as the…

  13. The Reaction Wheel Pendulum

    CERN Document Server

    Block, Daniel J; Spong, Mark W

    2007-01-01

    This monograph describes the Reaction Wheel Pendulum, the newest inverted-pendulum-like device for control education and research. We discuss the history and background of the reaction wheel pendulum and other similar experimental devices. We develop mathematical models of the reaction wheel pendulum in depth, including linear and nonlinear models, and models of the sensors and actuators that are used for feedback control. We treat various aspects of the control problem, from linear control of themotor, to stabilization of the pendulum about an equilibrium configuration using linear control, t

  14. Review of The Triumph of Numbers by I. B. Cohen

    Directory of Open Access Journals (Sweden)

    H.L. Vacher

    2008-01-01

    Full Text Available I. Bernard Cohen, The Triumph of Numbers: How Counting Shaped Modern Life. (New York: W.W. Norton & Company, 2005. 209 pp. $24.95 (USA. ISBN 0-393-05769-0.The premier historian of science ends his career telling how the world has become awash in numbers—“how numbers entered the conduct of life and of government, the understanding of nature, and the analysis of societies.” The stories begin with Kepler and end with Florence Nightingale. In between, major players include Galileo, Harvey, Leeuwenhoek, and Halley; Graunt and Petty; Jefferson and Franklin; Lavoisier, Sinclair, Pinel and Louis; Guerry and Quetelet. The book tells of the spread of what Cohen refers to as the “quantifying spirit” from physical science to “political arithmetic” (Sir William Petty, economics, and the beginning of psychiatry, sociology, medical statistics, and public health.

  15. Wheeled hopping robot

    Science.gov (United States)

    Fischer, Gary J.

    2010-08-17

    The present invention provides robotic vehicles having wheeled and hopping mobilities that are capable of traversing (e.g. by hopping over) obstacles that are large in size relative to the robot and, are capable of operation in unpredictable terrain over long range. The present invention further provides combustion powered linear actuators, which can include latching mechanisms to facilitate pressurized fueling of the actuators, as can be used to provide wheeled vehicles with a hopping mobility.

  16. Wheel Electrometer System

    Science.gov (United States)

    Calle, Carlos I.; Buehler, Martin G.; Mantovani, James G.; Buhler, Charles; Nomicki, Andrew

    2005-01-01

    Two documents describe a prototype system of electrometers for measuring electrostatic fields and electrostatic responses of soils on Mars and the Moon. The electrodes of this electrometer are embedded in a wheel of an exploratory robotic vehicle, utilizing the wheel motion to bring the electrodes into proximity or contact with the soil. Each electrode resides in one of two types of sensor modules: electric-field (ELF) or triboelectric (TRIBO). In either type, what is measured is simply the electric charge induced on the electrode by exposure to the external distribution of electrostatic charge. In an ELF module, the electrode is bare and recessed radially from the wheel surface. The ELF sensor provides a measure of the charge on a small patch of undisturbed soil as the wheel rolls forward. In a TRIBO module, the electrode is only slightly recessed and covered with a polymeric insulator flush with the wheel surface. Through contact electrification, the insulator exchanges charge with the soil. There are five TRIBO sensors, each containing an insulator made of a different polymer. The charge data gathered by the five TRIBO sensors can be used to determine how the soil fits into a triboelectric series.

  17. Sustainable Rural Energy: Traditional Water Wheels in Padang (PWW) Indonesia

    Science.gov (United States)

    Ibrahim, Gusri Akhyar; Haron, Che Hassan Che; Azhari, Che Husna

    2010-06-01

    Renewable and sustainable energy is increasingly gaining interest in current research circles due to the debates on renewable energy resources. It is essential for scientists and researchers to search for solutions in renewable energy resources, with effective technologies, and low cost in operation and maintenance. Hydro resources can be considered a potential renewable energy resource. The traditional water wheel with simple construction coupled with a basic concept of technology can be utilised as a renewable and sustainable rural energy system. This paper discusses the case of the water wheel as a renewable energy system employed in Padang, Indonesia. The Padang water wheel is constructed from hardwood material with a diameter of 300 cm and width of 40 cm. It is built on a river using water flow to generate the movement of the wheel. The water wheel application in the area showed that it is suitable to be utilised to elevate and distribute water to rice fields located at a higher level than the water level of the river. The water wheel capacity is about 100-120 liters/min. It could continuously irrigate ±5 ha. of the rice fields. One of the advantages of this water wheel type is to function as a green technology concept promising no negative effect on the environment. The traditional water wheel has also a big economic impact on the rural economy, increasing the productivity of the rice fields. The people of Padang live in a water landscape encompassing the water wheel as an ubiquitous part of their lives, hence they relate to it and the technology of fabrication as well as the utilisation, making it an amenable and effective technology, finding relevance in the modern world.

  18. Interaction between a railway track and uniformly moving tandem wheels

    Science.gov (United States)

    Belotserkovskiy, P. M.

    2006-12-01

    Interaction among loaded wheels via railway track is studied. The vertical parametric oscillations of an infinite row of identical equally spaced wheels, bearing constant load and uniformly moving over a railway track, are calculated by means of Fourier series technique. If the distance between two consecutive wheels is big enough, then one can disregard their interaction via the railway track and consider every wheel as a single one. In this case, however, the Fourier series technique represents an appropriate computation time-saving approximation to a Fourier integral transformation technique that describes the oscillations of a single moving wheel. Two schemes are considered. In the first scheme, every wheel bears the same load. In the second one, consecutive wheels bear contrarily directed loads of the same magnitude. The second scheme leads to simpler calculations and so is recommended to model the wheel-track interaction. The railway track periodicity due to sleeper spacing is taken into account. Each period is the track segment between two adjacent sleepers. A partial differential equation with constant coefficients governs the vertical oscillations of each segment. Boundary conditions bind the oscillations of two neighbour segments and provide periodicity to the track. The shear deformation in the rail cross-section strongly influences the parametric oscillations. It also causes discontinuity of the rail centre-line slope at any point, where a concentrated transverse force is applied. Therefore, Timoshenko beam properties with respect to the topic of this paper are discussed. Interaction between a railway track and a bogie moving at moderate speed is studied. The study points to influence of the bogie frame oscillations on variation in the wheel-rail contact force over the sleeper span. The simplified bogie model considered includes only the primary suspension. A static load applied to the bogie frame centre presents the vehicle body.

  19. Design and Trafficability Study of Flexible Wheel for Planetary Exploration Rover

    Institute of Scientific and Technical Information of China (English)

    LI Wen; GAO Feng; XU Guo-yan

    2007-01-01

    To reduce sending costs, a flexible wheel configuration is proposed. The wheel is made of titanium alloy (Ti-6Al-4V) in consideration of the planetary environment factors (i.e. strong radiation, big temperature differences, high vacuum), and mass constraint of launch vehicle. The advantages of the proposed wheel involves the potential for: ① small sending volume and mass, ② large deployed area and volume to reduce wheel loading, ③ a damping effect to smooth motion on rough terrain. To study the trafficability and tractive performance of the wheel concept, the drawbar pull and driven torque were calculated based on simplified model of terramechanics formulations. The results show that the wheel possesses sufficient drawbar pull to negotiate all types of soil stratums listed in this contribution.

  20. Big Society, Big Deal?

    Science.gov (United States)

    Thomson, Alastair

    2011-01-01

    Political leaders like to put forward guiding ideas or themes which pull their individual decisions into a broader narrative. For John Major it was Back to Basics, for Tony Blair it was the Third Way and for David Cameron it is the Big Society. While Mr. Blair relied on Lord Giddens to add intellectual weight to his idea, Mr. Cameron's legacy idea…

  1. The prospects for retail wheeling

    International Nuclear Information System (INIS)

    This paper as published is an outline of a presentation on retail wheeling of electric power. The topics discussed are development of increased wholesale transmission access, government regulatory policies on wholesale transmission, examples of past and present retail transmission access agreements, examples of Federal Energy Regulatory Commission jurisdiction over retail wheeling, and state policies on retail wheeling

  2. Tragedy and triumph in orbit the eighties and early nineties

    CERN Document Server

    Evans, Ben

    2012-01-01

    April 12, 2011, was the 50th anniversary of Yuri Gagarin's pioneering journey into space. To commemorate this momentous achievement, Springer-Praxis is producing a mini series of books that reveals how humanity's knowledge of flying, working, and living in space has grown in the last half century. Tragedy and Triumph in Orbit, the fourth book in the series, explores the tumultuous events of the 1980s and the beginning of the 1990s, a time when a reinvigorated Cold War between the United States and the Soviet Union bred further distrust and intense competition between the two old foes. As the Shuttle sought to fulfill its mandate of regular, routine access to space, a fatal Achilles heel in the system remained undetected until, one freezing January day in 1986, it made itself known with horrifying suddenness on millions of television screens across the world. Systemic flaws, and the urgent need to resolve them, led to several years of introspection, while the Soviet program seemed to prosper and cosmonauts sp...

  3. 3-D Color Wheels

    Science.gov (United States)

    DuBois, Ann

    2010-01-01

    The blending of information from an academic class with projects from art class can do nothing but strengthen the learning power of the student. Creating three-dimensional color wheels provides the perfect opportunity to combine basic geometry knowledge with color theory. In this article, the author describes how her seventh-grade painting…

  4. Getting Behind the Wheel

    Institute of Scientific and Technical Information of China (English)

    SEAN; O’CONNER

    2008-01-01

    I took the cramming school,the conveyor belt approach to learning to drive.As a passed and stamped graduate of the Oriental Fashion Driving School,I’m relieved that I no longer have to get up at 5 o’clock for a 7-to-12 seat behind the wheel

  5. Color Wheel Windows

    Science.gov (United States)

    Leonard, Stephanie

    2012-01-01

    In this article, the author describes a painting and drawing lesson which was inspired by the beautiful circular windows found in cathedrals and churches (also known as "rose windows"). This two-week lesson would reinforce both the concept of symmetry and students' understanding of the color wheel. (Contains 1 online resource.)

  6. Journey through the Trials and Triumphs of Disability

    Directory of Open Access Journals (Sweden)

    Helen L. Laas

    2012-05-01

    Full Text Available One Woman’s journey through the Trials and Triumphs of Disability, Disabled Peoples International 8th World Assembly 2011 Durban, South Africa, October 10–13, 2011. When embarking on my career as a teacher at a special school in South Africa, I never thought that a motor vehicle accident would place me in the position where my learners with disabilities suddenly saw me as an ally. Little did I realise the chasm that exists between able-bodied people and people with disabilities, or the remarkable role I would find myself in whilst actively addressing disability and Inclusive Education issues. My experiences with disability in South Africa drew encouraging attention from delegates at the Disabled People’s International 8th World Assembly when I shared my story. The resounding positive response affirmed that my experiences are not unique to nationality, gender, race or age, and are typical of the time and country in which I live, where people with disabilities are considered to have little potential, and woman with disabilities are further marginalised. In the infancy of our democracy, we are still in the early days of attending to equity amongst all South Africans. This story comprises both a narrative and a graphic presentation which run parallel, although not always telling an identical story; they complement one another and should be experienced simultaneously. Ultimately, it relates the success that can be achieved by pro-active people with disabilities as members of the South African society within their own spheres of knowledge and skill to change attitudes and practices of people without disabilities in education and local communities.

  7. Putting China On Wheels

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Cars and bicycles jockey fiercely for road space everyday at rush hour in Beijing,Shanghai, Guangzhou andother big cities. Traffic congestion is commonplace, and auto accidents have risen alarmingly. This is directly attributable to the increased number of vehicles

  8. The ubiquitous photonic wheel

    CERN Document Server

    Aiello, Andrea

    2016-01-01

    A circularly polarized electromagnetic plane wave carries an electric field that rotates clockwise or counterclockwise around the propagation direction of the wave. According to the handedness of this rotation, its \\emph{longitudinal} spin angular momentum density is either parallel or antiparallel to the propagation of light. However, there are also light waves that are not simply plane and carry an electric field that rotates around an axis perpendicular to the propagation direction, thus yielding \\emph{transverse} spin angular momentum density. Electric field configurations of this kind have been suggestively dubbed "photonic wheels". It has been recently shown that photonic wheels are commonplace in optics as they occur in electromagnetic fields confined by waveguides, in strongly focused beams, in plasmonic and evanescent waves. In this work we establish a general theory of electromagnetic waves {propagating along a well defined direction, which carry} transverse spin angular momentum density. We show th...

  9. Experiments with Electrodynamic Wheels

    Science.gov (United States)

    Gaul, Nathan; Corey, Daniel; Cordrey, Vincent; Majewski, Walerian

    2015-04-01

    Our experiments were involving inductive magnetic levitation. A Halbach array is a system in which a series of magnets is arranged in a manner such that the magnetic field is cancelled on one side of the array while strengthening the field on the other. We constructed two circular Halbach wheels, making the strong magnetic field on the outer rim of the ring. Such system is usually dubbed as an Electrodynamic Wheel (EDW). Rotating this wheel around a horizontal axis above a flat conducting surface should induce eddy currents in said surface through the variable magnetic flux. The eddy currents produce, in turn, their own magnetic fields which interact with the magnets of the EDW. We demonstrated that these interactions produce both drag and lift forces on the EDW which can theoretically be used for lift and propulsion of the EDW. The focus of our experiments is determining how to maximize the lift-to-drag ratio by the proper choice of the induction element. We will also describe our experiments with a rotating circular Halbach array having the strong magnetic field of about 1 T on the flat side of the ring, and acting as a hovercraft.

  10. Robotic Two-Wheeled Vehicle

    Science.gov (United States)

    Nesnas, Issa A. D. (Inventor); Matthews, Jaret B. (Inventor); Edlund, Jeffrey E. (Inventor); Burdick, Joel (Inventor); Abad-Manterola, Pablo (Inventor)

    2014-01-01

    A robotic two-wheeled vehicle comprising a connection body interposed between the two wheels are described. A drum can be coaxially located in a central region of the connection body and can support a hollow arm projecting radially from the drum. A tether can be inserted in the arm and connected to a second drum. Instruments and sensors can be accommodated in a case housed inside each wheel.

  11. CRANE WHEELS PRODUCTION QUALITY CONTROL

    OpenAIRE

    OTTO GRIGOROV; SERHY GUBSKIY; ANTON OKUN

    2014-01-01

    Quality control of crane wheels is an important part for support of crane mechanisms permanent operation. Normal functioning of logistics systems requires preventing of crane downtimes and delays. The research results of the impact of the crane wheels (710 mm diameter, 65 steel) surface hardness on coercivity indicators are presented in this paper. Obtained research results of dependence between the coercivity indicators and the crane wheels rolling surface hardness for their use in practice ...

  12. Driver at the wheel?

    OpenAIRE

    Taede Tillema, Jaco Berveling, George Gelauff, Jan van der Waard, Lucas Harms en Harry Derriks

    2015-01-01

    Self-driving cars can change our society radically. Whether that happens depends on how much the car can actually do itself, but also on what the consumer wants. Will cars become a luxury second home or does a car driver remain a necessity? Also the sharing-economy has an impact. If many people will share self-driving vehicles and rides, this may change the traffic and transport system fundamentally.These are some of the conclusions of the report 'Driver at the wheel - Self-driving vehicles a...

  13. A Country on Wheels

    Institute of Scientific and Technical Information of China (English)

    小雨

    2007-01-01

    Cars are an important part of life in the United States. Most people feel that they are poor without cars. Though he is poor, he doesn't feel really poor when he has a car. Henry Ford was the man who first started making cars. Maybe, he didn't know how much the car was going to affect(影响) the United States. The cars made the United States a country on wheels(轮子). And they have helped to make the United States rich and modern.

  14. Reaction Wheel with Embedded MEMS IMU Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The innovation is to embed a MEMS IMU Sensor Chip into a reaction wheel to measure its spin rate as well as wheel attitude rate. We propose to use a reaction wheel...

  15. Mechanical Design Engineering Enabler Project wheel and wheel drives

    Science.gov (United States)

    Nutt, Richard E.; Couch, Britt K.; Holley, John L., Jr.; Garris, Eric S.; Staut, Paul V.

    1992-01-01

    Our group was assigned the responsibility of designing the wheel and wheel drive system for a proof-of-concept model of the lunar-based ENABLER. ENABLER is a multi-purpose, six wheeled vehicle designed to lift and transport heavy objects associated with the construction of a lunar base. The resulting design was based on the performance criteria of the ENABLER. The drive system was designed to enable the vehicle to achieve a speed of 7 mph on a level surface, climb a 30 percent grade, and surpass a one meter high object and one meter wide crevice. The wheel assemblies were designed to support the entire weight of the vehicle on two wheels. The wheels were designed to serve as the main component of the vehicle's suspension and will provide suitable traction for lunar-type surfaces. The expected performance of the drive system for the ENABLER was influenced by many mechanical factors. The expected top speed on a level sandy surface is 4 mph instead of the desired 7 mph. This is due to a lack of necessary power at the wheels. The lack of power resulted from dimension considerations that allowed only an eight horsepower engine and also from mechanical inefficiencies of the hydraulic system. However, the vehicle will be able to climb a 30 percent grade, surpass a one meter high object and one meter wide crevice. The wheel assemblies will be able to support the entire weight of the vehicle on two wheels. The wheels will also provide adequate suspension for the vehicle and sufficient traction for lunar-type surfaces.

  16. The outlook for wheeling

    Energy Technology Data Exchange (ETDEWEB)

    Zimmer, M.J.

    1990-04-01

    There is a continued national interest in decentralized power sources involving cogeneration and independent power production. But while these issues are debated in the halls of Congress, and the subject of generic rulemaking debate before the FERC, the real action is occurring elsewhere. Key momentum is building in the states ad individual electric utility systems requiring Federal Energy Regulatory Commission (FERC) and state commission review of discrete applications for case by case review. These reflect the pressure of competitive forces building within the industry from other electric utilities, power export marketeers, environmental and siting regulation, and from financial institutions. The underlying intent of PURPA is to encourage and provide incentives for the development of alternate energy sources to provide the efficient use of our nation's natural resources. Under PURPA the Commission can not direct an electric utility to provide transmission services. However, this power can only be exercised after a series of complex findings by the Commission through evidentiary hearings. In addition, PURPA amended other sections of the Federal Power Act to provide various rate incentives and exemptions for cogeneration and small power production facilities including the right for interconnection to the electric utility. The scope of such interconnection rights, and whether they might encompass broader transmission rights for QFs has yet to be tested. This paper describes wheeling rules prior to PURPA, the PURPA amendments governing wheeling; states' views; and the need for a review.

  17. GM Prototype Moon Buggy Wheel

    Science.gov (United States)

    1967-01-01

    Under the direction of Marshall Space Flight Center (MSFC), the Lunar Roving Vehicle (LRV) was designed to allow Apollo astronauts a greater range of mobility during lunar exploration missions. During the development process, LRV prototype wheels underwent soil tests in building 4481 at Marshall Space Flight Center (MSFC). Pictured is the GM wheel design.

  18. Big Data

    Directory of Open Access Journals (Sweden)

    Prachi More

    2013-05-01

    Full Text Available Demand and spurt in collections and accumulation of data has coined new term “Big Data” has begun. Accidently, incidentally and by interaction of people, information so called data is massively generated. This BIG DATA is to be smartly and effectively used Computer scientists, physicists, economists, mathematicians, political scientists, bio-informaticists, sociologists and many Variety of Intellegesia debate over the potential benefits and costs of analysing information from Twitter, Google, Facebook, Wikipedia and every space where large groups of people leave digital traces and deposit data. Given the rise of Big Data as both a phenomenon and a methodological persuasion, it is time to start critically interrogating this phenomenon, its assumptions and its biases. Big data, which refers to the data sets that are too big to be handled using the existing database management tools, are emerging in many important applications, such as Internet search, business informatics, social networks, social media, genomics, and meteorology. Big data presents a grand challenge for database and data analytics research. This paper is a blend of non-technical and introductory-level technical detail, ideal for the novice. We conclude with some technical challenges as well as the solutions that can be used to these challenges. Big Data differs from other data with five characteristics like volume, variety, value, velocity and complexity. The article will focus on some current and future cases and causes for BIG DATA.

  19. Big Data

    DEFF Research Database (Denmark)

    Madsen, Anders Koed; Flyverbom, Mikkel; Hilbert, Martin;

    2016-01-01

    The claim that big data can revolutionize strategy and governance in the context of international relations is increasingly hard to ignore. Scholars of international political sociology have mainly discussed this development through the themes of security and surveillance. The aim of this paper is...... to outline a research agenda that can be used to raise a broader set of sociological and practice-oriented questions about the increasing datafication of international relations and politics. First, it proposes a way of conceptualizing big data that is broad enough to open fruitful investigations...... into the emerging use of big data in these contexts. This conceptualization includes the identification of three moments contained in any big data practice. Second, it suggests a research agenda built around a set of subthemes that each deserve dedicated scrutiny when studying the interplay between big...

  20. Squeaky Wheel Optimization

    CERN Document Server

    Clements, D P; 10.1613/jair.561

    2011-01-01

    We describe a general approach to optimization which we term `Squeaky Wheel' Optimization (SWO). In SWO, a greedy algorithm is used to construct a solution which is then analyzed to find the trouble spots, i.e., those elements, that, if improved, are likely to improve the objective function score. The results of the analysis are used to generate new priorities that determine the order in which the greedy algorithm constructs the next solution. This Construct/Analyze/Prioritize cycle continues until some limit is reached, or an acceptable solution is found. SWO can be viewed as operating on two search spaces: solutions and prioritizations. Successive solutions are only indirectly related, via the re-prioritization that results from analyzing the prior solution. Similarly, successive prioritizations are generated by constructing and analyzing solutions. This `coupled search' has some interesting properties, which we discuss. We report encouraging experimental results on two domains, scheduling problems that ari...

  1. PHENOMENON OF CARVED DRIVING WHEELS

    Institute of Scientific and Technical Information of China (English)

    LI Xianghua; ZHANG Jianwu

    2007-01-01

    A newly found phenomenon of carved driving wheels of a rea-wheel-drive tractor used in an airport is discussed. The circum of every driving wheel is damaged at three regions, which distribute regularly and uniformly. Everyday, the tractor tows a trailer which are times heavier than the tractor, and moves on the same road in the airport. The phenomenon is explained by the torsional self-excited vibration system of the powertrain. The simplified torsional vibration system is discribed by a 2-order ordinary differential equation, which has a limit circle. Experiments and numerical simulations show the followings: Because of the heavy trailer, the slip ratio of the tractor's driving wheels is very large. Therefore, there is severe torsional self-excited vibration in the tractor's drivetrain, and the self-excited vibration results in severe and regular fluctuations of the rear wheel's velocity. The severe fluctuations in velocity fastens the damage of the driving wheels. At the same time, the time interval in which an arbitrary point in the circum of the driving wheel contacts with the road twice is two times more than the period of the torsional self-excited vibration, and this times explained the existence of three damaged regions. At last, it points out that the phenomenon can be avoided when the torsional damping is large enough.

  2. 49 CFR 570.63 - Wheel assemblies.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 6 2010-10-01 2010-10-01 false Wheel assemblies. 570.63 Section 570.63 Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY TRAFFIC SAFETY... 10,000 Pounds § 570.63 Wheel assemblies. (a) Wheel integrity. A tire rim, wheel disc or spider...

  3. Big data

    DEFF Research Database (Denmark)

    Madsen, Anders Koed; Ruppert, Evelyn; Flyverbom, Mikkel;

    2016-01-01

    The claim that big data can revolutionize strategy and governance in the context of international relations is increasingly hard to ignore. Scholars of international political sociology have mainly discussed this development through the themes of security and surveillance. The aim of this paper is...... to outline a research agenda that can be used to raise a broader set of sociological and practice-oriented questions about the increasing datafication of international relations and politics. First, it proposes a way of conceptualizing big data that is broad enough to open fruitful investigations...... into the emerging use of big data in these contexts. This conceptualization includes the identification of three moments that is contained in any big data practice. Secondly, it suggest a research agenda built around a set of sub-themes that each deserve dedicated scrutiny when studying the interplay...

  4. Wheels lining up for ATLAS

    CERN Multimedia

    2003-01-01

    On 30 October, the mechanics test assembly of the central barrel of the ATLAS tile hadronic calorimeter was completed in building 185. It is the second wheel for the Tilecal completely assembled this year.

  5. Strain measurements at railway wheels

    International Nuclear Information System (INIS)

    The development of the radial strain component in railway wheels was investigated by neutron diffraction. In the as manufactured state four railway wheels were investigated. In all four wheels no significant strains were found. After 18,400 km usage first strain gradients close to the outer surface of the wheels were detected. In axial middle ranges the changes in strain are weak. After an usage of 61,000 km the gradients becomes strong at the axial outer position between about +700 με close below the tread and -500 με in a depth of 12.5 mm below the tread. At axial middle positions also strain gradients are formed. The end of live state (510,000 km) differs only slightly from the state measured after a usage of 61,000 km

  6. Honda CBR600RR Vs Kawasaki Vs Yamaha YZF-R6 Vs Triumph

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    上期我们为大家带来2009款中量级超级跑车对比的上部分内容,在专业且残酷的对比测评中,Yamaha YZF-R6.Suzuki GSX-R600、Triumph Daytona 675分别获得四,五、六名。

  7. Big Egos in Big Science

    DEFF Research Database (Denmark)

    Jeppesen, Jacob; Vaarst Andersen, Kristina; Lauto, Giancarlo; Valentin, Finn

    utilize a stochastic actor oriented model (SAOM) to analyze both network endogeneous mechanisms and individual agency driving the collaboration network and further if being a Big Ego in Big Science translates to increasing performance. Our findings suggest that the selection of collaborators is not based...... on preferentialattachment, but more of an assortativity effect creating not merely a rich-gets-richer effect but an elitist network with high entry barriers. In this acclaimed democratic and collaborative environment of Big Science, the elite closes in on itself. We propose this tendency to be even...

  8. The wheel of retail gravitation?

    OpenAIRE

    Brown, S.

    1992-01-01

    Reilly's Law of Retail Gravitation ranks among the classics of marketing geography. In this paper an examination of the evolution of Reilly's law is made, the contemporaneous wheel of retailing theory being used as an organisational framework. In line with the wheel, the gravity model commenced as a simple conceptualisation of consumer spatial behaviour, became increasingly sophisticated through time, and thereby created conditions conducive to the reemergence of the basic interaction model. ...

  9. Chopping-Wheel Optical Attenuator

    Science.gov (United States)

    Leviton, Douglas B.

    1988-01-01

    Star-shaped rotating chopping wheel provides adjustable time-averaged attenuation of narrow beam of light without changing length of optical path or spectral distribution of light. Duty cycle or attenuation factor of chopped beam controlled by adjusting radius at which beam intersects wheel. Attenuation factor independent of wavelength. Useful in systems in which chopping frequency above frequency-response limits of photodetectors receiving chopped light. Used in systems using synchronous detection with lock-in amplifiers.

  10. Estimating the Backup Reaction Wheel Orientation Using Reaction Wheel Spin Rates Flight Telemetry from a Spacecraft

    Science.gov (United States)

    Rizvi, Farheen

    2013-01-01

    A report describes a model that estimates the orientation of the backup reaction wheel using the reaction wheel spin rates telemetry from a spacecraft. Attitude control via the reaction wheel assembly (RWA) onboard a spacecraft uses three reaction wheels (one wheel per axis) and a backup to accommodate any wheel degradation throughout the course of the mission. The spacecraft dynamics prediction depends upon the correct knowledge of the reaction wheel orientations. Thus, it is vital to determine the actual orientation of the reaction wheels such that the correct spacecraft dynamics can be predicted. The conservation of angular momentum is used to estimate the orientation of the backup reaction wheel from the prime and backup reaction wheel spin rates data. The method is applied in estimating the orientation of the backup wheel onboard the Cassini spacecraft. The flight telemetry from the March 2011 prime and backup RWA swap activity on Cassini is used to obtain the best estimate for the backup reaction wheel orientation.

  11. Big Surveys, Big Data Centres

    Science.gov (United States)

    Schade, D.

    2016-06-01

    Well-designed astronomical surveys are powerful and have consistently been keystones of scientific progress. The Byurakan Surveys using a Schmidt telescope with an objective prism produced a list of about 3000 UV-excess Markarian galaxies but these objects have stimulated an enormous amount of further study and appear in over 16,000 publications. The CFHT Legacy Surveys used a wide-field imager to cover thousands of square degrees and those surveys are mentioned in over 1100 publications since 2002. Both ground and space-based astronomy have been increasing their investments in survey work. Survey instrumentation strives toward fair samples and large sky coverage and therefore strives to produce massive datasets. Thus we are faced with the "big data" problem in astronomy. Survey datasets require specialized approaches to data management. Big data places additional challenging requirements for data management. If the term "big data" is defined as data collections that are too large to move then there are profound implications for the infrastructure that supports big data science. The current model of data centres is obsolete. In the era of big data the central problem is how to create architectures that effectively manage the relationship between data collections, networks, processing capabilities, and software, given the science requirements of the projects that need to be executed. A stand alone data silo cannot support big data science. I'll describe the current efforts of the Canadian community to deal with this situation and our successes and failures. I'll talk about how we are planning in the next decade to try to create a workable and adaptable solution to support big data science.

  12. Research on the 2-axis cup-wheel dressing technology of arc-diamond grinding wheel

    Science.gov (United States)

    Chang, X. L.; Wu, H. Y.; Peng, Y. F.

    2014-08-01

    The precision dressing of arc-diamond wheel is very hard, expensive and time-consuming because of the super-hard diamond particles and complicated geometrical shape. This paper aims to investigate the cup-wheel dressing technology to realize the high-efficiency regeneration of the arc-diamond wheel. A two-axis cup-wheel dressing technique for precision dressing arc-diamond wheel was suggested and tested. The dressing mechanism of 2-axis cup-wheel was studied. The dressing algorithm and error compensation method were further investigated to improve the dressing precision and efficiency. The experimental results show that the 2-axis cup-wheel dressing technique is valid and applicable to realize the precision dressing of arc-diamond wheel. The machined optical surface condition was apparently improved with the cup-wheel dressed diamond wheel and even became much better when the error compensation algorithm was performed on the arc-diamond wheel.

  13. Big Science

    International Nuclear Information System (INIS)

    Astronomy, like particle physics, has become Big Science where the demands of front line research can outstrip the science budgets of whole nations. Thus came into being the European Southern Observatory (ESO), founded in 1962 to provide European scientists with a major modern observatory to study the southern sky under optimal conditions

  14. Big Dreams

    Science.gov (United States)

    Benson, Michael T.

    2015-01-01

    The Keen Johnson Building is symbolic of Eastern Kentucky University's historic role as a School of Opportunity. It is a place that has inspired generations of students, many from disadvantaged backgrounds, to dream big dreams. The construction of the Keen Johnson Building was inspired by a desire to create a student union facility that would not…

  15. Two new wheels for ATLAS

    CERN Multimedia

    2002-01-01

    Juergen Zimmer (Max Planck Institute), Roy Langstaff (TRIUMF/Victoria) and Sergej Kakurin (JINR), in front of one of the completed wheels of the ATLAS Hadronic End Cap Calorimeter. A decade of careful preparation and construction by groups in three continents is nearing completion with the assembly of two of the four 4 m diameter wheels required for the ATLAS Hadronic End Cap Calorimeter. The first two wheels have successfully passed all their mechanical and electrical tests, and have been rotated on schedule into the vertical position required in the experiment. 'This is an important milestone in the completion of the ATLAS End Cap Calorimetry' explains Chris Oram, who heads the Hadronic End Cap Calorimeter group. Like most experiments at particle colliders, ATLAS consists of several layers of detectors in the form of a 'barrel' and two 'end caps'. The Hadronic Calorimeter layer, which measures the energies of particles such as protons and pions, uses two techniques. The barrel part (Tile Calorimeter) cons...

  16. Big Opportunities and Big Concerns of Big Data in Education

    Science.gov (United States)

    Wang, Yinying

    2016-01-01

    Against the backdrop of the ever-increasing influx of big data, this article examines the opportunities and concerns over big data in education. Specifically, this article first introduces big data, followed by delineating the potential opportunities of using big data in education in two areas: learning analytics and educational policy. Then, the…

  17. Reaction Wheel Disturbance Model Extraction Software Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Reaction wheel disturbances are some of the largest sources of noise on sensitive telescopes. Such wheel-induced mechanical noises are not well characterized....

  18. New steering mechanism for wheeled mobile robots

    Institute of Scientific and Technical Information of China (English)

    Sidibe Marie Bernard; FU Yi-li; XU He; MA Yu-lin

    2007-01-01

    A new castor wheel mechanism for omni-directional mobile platform is presented. A motion of translation is transformed into a rotation to steer the wheel with the help of a helical path fits into a translation joint and three rollers whose axes are connected to the driving shaft of the wheel. When the path moves in translation it acts on the rollers for steering. The path-roller friction transmission, the wheel kinematics and the maneuverability have been analyzed.

  19. Some peculiarities of corrosion of wheel steel

    OpenAIRE

    Alexander SHRAMKO; Alfred KOZLOWSKY; Elena BELAJA; Yuriy PROIDAK; Pinchuk, Sofia; Gubenko, Svetlana

    2009-01-01

    Corrosion mechanism and rate of different chemical composition and structural condition of wheel steel were investigated. It was shown that “white layers”, variation in grain size and banding of wheel steel structure results in corrosion rate. Microstructure of steel from different elements of railway wheels after operation with corrosion was investigated. Wheel steel with addition of vanadium corroded more quickly than steel without vanadium. Non-metallic inclusions are the centre of corrosi...

  20. Big Data and Big Science

    OpenAIRE

    Di Meglio, Alberto

    2014-01-01

    Brief introduction to the challenges of big data in scientific research based on the work done by the HEP community at CERN and how the CERN openlab promotes collaboration among research institutes and industrial IT companies. Presented at the FutureGov 2014 conference in Singapore.

  1. 49 CFR 570.10 - Wheel assemblies.

    Science.gov (United States)

    2010-10-01

    ... Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY TRAFFIC SAFETY... Pounds or Less § 570.10 Wheel assemblies. (a) Wheel integrity. A tire rim, wheel disc, or spider shall... rim bead area shall not exceed one-eighth of an inch of total indicated runout. (1)...

  2. 49 CFR 215.103 - Defective wheel.

    Science.gov (United States)

    2010-10-01

    ..., DEPARTMENT OF TRANSPORTATION RAILROAD FREIGHT CAR SAFETY STANDARDS Freight Car Components Suspension System..., is 11/2 inches, or more; (c) The thickness of a rim of a wheel on the car is 11/16 of an inch, or less; (d) A wheel rim, flange, plate, or hub area on the car has a crack or break; (e) A wheel on...

  3. Trials and Triumph: Lesbian and Gay Young Adults Raised in a Rural Context

    Directory of Open Access Journals (Sweden)

    Angie L. Dahl

    2015-09-01

    Full Text Available The rural context at times is characterized by heteronormativity and conservatism. For individuals who identify as a sexual minority (lesbian, gay, bisexual, transgender and/or queer, the rural context may pose particular challenges to the development of a healthy, coherent sense of self. Seven young adults (18–24 who identified as gay or lesbian participated in in-depth interviews regarding their experiences coming out in a rural Appalachian context. Findings suggest sexual minority individuals experience both trials and triumphs coming out in the rural context. Two overarching themes and six subthemes are discussed with implications for supporting sexual minority youth in the rural context.

  4. Triumph & Commemoration: Collective Imagination and the ‘Ground Zero Mosque’ Controversy

    OpenAIRE

    Powell, Julie M.

    2013-01-01

    This study reassesses the meaning of the ‘Ground Zero Mosque’ controversy of 2010 through the lens of urban sociology and collective imagination. It utilizes the imaginative fruits of civic forums, such as “Imagine NY” and “Listening to the City,” to determine New Yorkers’ collective vision for the rehabilitation of Ground Zero and Lower Manhattan in the aftermath of 9/11. Articulated as a clarion call for the manifestation of commemoration and triumph over terrorism in the New York cityscape...

  5. Review of The Triumph of Numbers by I. B. Cohen

    OpenAIRE

    H.L. Vacher

    2008-01-01

    I. Bernard Cohen, The Triumph of Numbers: How Counting Shaped Modern Life. (New York: W.W. Norton & Company, 2005). 209 pp. $24.95 (USA). ISBN 0-393-05769-0.The premier historian of science ends his career telling how the world has become awash in numbers—“how numbers entered the conduct of life and of government, the understanding of nature, and the analysis of societies.” The stories begin with Kepler and end with Florence Nightingale. In between, major players include Galileo, Harvey, Leeu...

  6. The Influence of Wheel/Rail Contact Conditions on the Microstructure and Hardness of Railway Wheels

    OpenAIRE

    Paul Molyneux-Berry; Claire Davis; Adam Bevan

    2014-01-01

    The susceptibility of railway wheels to wear and rolling contact fatigue damage is influenced by the properties of the wheel material. These are influenced by the steel composition, wheel manufacturing process, and thermal and mechanical loading during operation. The in-service properties therefore vary with depth below the surface and with position across the wheel tread. This paper discusses the stress history at the wheel/rail contact (derived from dynamic simulations) and observed variati...

  7. Wheel Wear and Rail Damage Prediction for Wheels Turned with Thin Flanges

    OpenAIRE

    Muhamedsalih, Yousif; Bevan, Adam; Stow, Julian

    2016-01-01

    Economic Tyre Turning (ETT) is the process of turning wheels to a profile that has the same tread shape but a thinner flange than the design case, allowing less material to be removed from the wheel diameter. ETT can allow maintainers to extend wheel life, particularly when the wheel is approaching its minimum diameter. Modern wheel lathes are typically capable of turning such profiles but GB railway group standards do not currently permit their use. This paper investigates the effect of usin...

  8. Big queues

    CERN Document Server

    Ganesh, Ayalvadi; Wischik, Damon

    2004-01-01

    Big Queues aims to give a simple and elegant account of how large deviations theory can be applied to queueing problems. Large deviations theory is a collection of powerful results and general techniques for studying rare events, and has been applied to queueing problems in a variety of ways. The strengths of large deviations theory are these: it is powerful enough that one can answer many questions which are hard to answer otherwise, and it is general enough that one can draw broad conclusions without relying on special case calculations.

  9. Networking for big data

    CERN Document Server

    Yu, Shui; Misic, Jelena; Shen, Xuemin (Sherman)

    2015-01-01

    Networking for Big Data supplies an unprecedented look at cutting-edge research on the networking and communication aspects of Big Data. Starting with a comprehensive introduction to Big Data and its networking issues, it offers deep technical coverage of both theory and applications.The book is divided into four sections: introduction to Big Data, networking theory and design for Big Data, networking security for Big Data, and platforms and systems for Big Data applications. Focusing on key networking issues in Big Data, the book explains network design and implementation for Big Data. It exa

  10. Assessment of scatter for the micro-CT subsystem of the trimodality FLEX Triumph (TM) preclinical scanner

    NARCIS (Netherlands)

    Gutierrez, Daniel; Zaidi, Habib

    2011-01-01

    Purpose: This work aims at assessing, through experimental measurements and Monte Carlo calculations, the scatter to primary ratio (SPR) for the micro-CT subsystem of the FLEX Triumph (TM) preclinical PET-CT scanner to improve its quantitative capabilities. Methods: Experimental measurements were ca

  11. Big data analytics turning big data into big money

    CERN Document Server

    Ohlhorst, Frank J

    2012-01-01

    Unique insights to implement big data analytics and reap big returns to your bottom line Focusing on the business and financial value of big data analytics, respected technology journalist Frank J. Ohlhorst shares his insights on the newly emerging field of big data analytics in Big Data Analytics. This breakthrough book demonstrates the importance of analytics, defines the processes, highlights the tangible and intangible values and discusses how you can turn a business liability into actionable material that can be used to redefine markets, improve profits and identify new business opportuni

  12. The mainstream is not electable: when vision triumphs over representativeness in leader emergence and effectiveness.

    Science.gov (United States)

    Halevy, Nir; Berson, Yair; Galinsky, Adam D

    2011-07-01

    Theories of visionary leadership propose that groups bestow leadership on exceptional group members. In contrast, social identity perspectives claim that leadership arises, in part, from a person's ability to be seen as representative of the group. Integrating these perspectives, the authors propose that effective leaders often share group members' perspectives concerning the present, yet offer a unique and compelling vision for the group's future. In addition, although intergroup contexts may increase the value of representativeness, the authors predict that vision dominates representativeness in single-group situations characterized by high levels of collective stress (e.g., a natural disaster). Five studies demonstrated that visionary leaders (those who offer novel solutions to their group's predicament) attract more followers, promote group identification and intrinsic motivation, mobilize collective action, and effectively regulate group members' emotions and reactions to crises compared to representative leaders. The authors discuss when, why, and how vision triumphs over representativeness in leader emergence and effectiveness. PMID:21467538

  13. ATLAS- lowering the muon small wheel

    CERN Multimedia

    2008-01-01

    ATLAS - the two muon small wheels lowered into the cavern Like briefly separated twin sisters, ATLAS’s small wheels were once again united at the experiment’s surface building at Point 1 on St Valentine’s Day. The lowering of the small wheels into the tunnel will mark the end of the installation of detector components for the experiment. At around 15.40 on Friday 29th February the ATLAS collaboration cracked open the champagne as the second of the small wheels was lowered into the cavern.

  14. Finite element simulation of wheel impact test

    Directory of Open Access Journals (Sweden)

    S.H. Yang

    2008-06-01

    Full Text Available Purpose: In order to achieve better performance and quality, the wheel design and manufacturing use a number of wheel tests (rotating bending test, radial fatigue test, and impact test to insure that the wheel meets the safety requirements. The test is very time consuming and expensive. Computer simulation of these tests can significantly reduce the time and cost required to perform a wheel design. In this study, nonlinear dynamic finite element is used to simulate the SAE wheel impact test.Design/methodology/approach: The test fixture used for the impact test consists of a striker with specified weight. The test is intended to simulate actual vehicle impact conditions. The tire-wheel assembly is mounted at 13° angle to the vertical plane with the edge of the weight in line with outer radius of the rim. The striker is dropped from a specified height above the highest point of the tire-wheel assembly and contacts the outboard flange of the wheel.Because of the irregular geometry of the wheel, the finite element model of an aluminium wheel is constructed by tetrahedral element. A mesh convergence study is carried out to ensure the convergence of the mesh model. The striker is assumed to be rigid elements. Initially, the striker contacts the highest area of the wheel, and the initial velocity of the striker is calculated from the impact height. The simulated strains at two locations on the disc are verified by experimental measurements by strain gages. The damage parameter of a wheel during the impact test is a strain energy density from the calculated result.Findings: The prediction of a wheel failure at impact is based on the condition that fracture will occur if the maximum strain energy density of the wheel during the impact test exceeds the total plastic work of the wheel material from tensile test. The simulated results in this work show that the total plastic work can be effectively employed as a fracture criterion to predict a wheel

  15. Big Data : Overview

    OpenAIRE

    Richa Gupta; Sunny Gupta; Anuradha Singhal

    2014-01-01

    Big data is data that exceeds the processing capacity of traditional databases. The data is too big to be processed by a single machine. New and innovative methods are required to process and store such large volumes of data. This paper provides an overview on big data, its importance in our live and some technologies to handle big data.

  16. Big Data: Overview

    OpenAIRE

    Gupta, Richa; Gupta, Sunny; Singhal, Anuradha

    2014-01-01

    Big data is data that exceeds the processing capacity of traditional databases. The data is too big to be processed by a single machine. New and innovative methods are required to process and store such large volumes of data. This paper provides an overview on big data, its importance in our live and some technologies to handle big data.

  17. Entropy parameters for desiccant wheel design

    International Nuclear Information System (INIS)

    In this work a thermodynamic analysis of a desiccant wheel is proposed to investigate and identify the optimum size and operating regime of this device. A steady state entropy generation expression, based on effectiveness parameters suitable for desiccant wheels operability, is obtained applying a control volume approach and assuming perfect gas behaviour of the binary air–vapour mixture. A new entropy generation number NL is defined using a minimum indicative value of the entropy generation SL,min and investigated in order to obtain useful criteria for desiccant wheels optimization. The effectiveness-NTU design method is employed by combining solution of thermal exchange efficiency for rotary heat exchanger with the characteristic potential method, under the conditions of heat and mass transfer analogy. The analysis is applied to a specific desiccant wheel and NL variation with NTU is explored under various operative conditions and wheels characteristics in terms of dimensionless velocity and flow unbalance ratio. - Highlights: • Steady state entropy generation based on effectiveness parameters for heat and mass transfer. • Definition of a new entropy generation number NL for desiccant wheel. • Least irreversible features for a defined dehumidification rate of the desiccant wheel. • NL can be used as an optimization parameter for desiccant wheels design and control

  18. Development of the FASTER Wheeled Bevameter

    Science.gov (United States)

    Richter, L.; Eder, V.; Hoheneder, W.; Imhof, B.; Lewinger, W.; Ransom, S.; Saaj, C.; Weclewski, P.; Waclavicek, R.,

    2014-04-01

    This paper describes the development of a Wheeled Bevameter (WB) within the FASTER project (Forward Acquisition of Soil and Terrain Data for Exploration Rovers), funded by the European Union's FP7 programme. In FASTER, novel and innovative concepts for in situ forward sensing of soil properties and terrain conditions in the planned path of a planetary rover are developed. Terrain strength measurements for assessment of the mobility of crosscountry vehicles have decades of heritage on Earth, but typically trafficability of terrains is only gauged by human operators ahead of vehicle operations rather than in-line by probes deployed from the vehicle itself, as is intended for FASTER. For FASTER, a Wheeled Bevameter (WB) has been selected as the terrain sensing instrument for the vehicle. Wheeled Bevameters are suitable for terrain measurements while driving but traditionally have mostly been employed on terrestrial vehicles to evaluate particular wheel designs. The WB as conceived in FASTER uses a dedicated, passive-rolling test wheel (‚test wheel') placed on the terrain as the loading device to enable to determine bearing strength, compressive strength and shear strength of the terrain immediately ahead of the vehicle, as well as rover-terrain interaction parameters used in semi-empirical vehicle-terrain traction models. The WB includes a placement mechanism for the test wheel. The test wheel would remain lowered onto the ground during nominal rover motion, including when climbing and descending slopes. During normal operations, the placement mechanism assumes the function of a passive suspension of the wheel, allowing it to follow the terrain contour. Quantities measured with the WB are: test wheel sinkage (through a laser sensor), test wheel vertical load, test wheel horizontal reaction force, and test wheel rotation rate. Measurements are performed while the rover is in motion. Measured test wheel rotation rate (with appropriate corrections for slight skid) can

  19. Eddy current arrays for wheel inspection

    Science.gov (United States)

    Leclerc, Rémi

    2001-04-01

    Wheel inspections are routine and very time-consuming, especially for large aircraft wheels where a single-coil probe is moved manually taking precious long minutes. Eddy current arrays can decrease the inspection time by reducing to one the number of rotations needed to completely cover the wheel surface. Since the EC array probe fits the profile of the wheel, manipulation is easy and the lift-off is kept constant improving signal quality. C-scan displays assist the analysis and help locate the defect by dividing the inspected wheel surface into a small grid. Furthermore, the impedance plane and the strip chart, for all the channels used to build the C-scan, are accessible to provide better sizing accuracy of the defect.

  20. Biaxial wheel/hub test facility. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, G.; Grubisic, V. [eds.

    2000-07-01

    The 4{sup th} meeting aims to exchange the experience and knowledge of engineers during several presentations and discussions about new developments required for a reliable, time and cost reducing validation of the wheel/hub assembly. Tremendous development of the wheel performance, described by the ratio of the rated load (kg) versus the wheel weight (kg) had taken place during the last 5000 years. Starting from the ratio of 3 for wooden 2-piece-disc-wheels in Mesopotamia it needed nearly 1000 years to increase the ratio to approx 5 at light-weight spoke wheels for fighting carriages, found in the grave of king Tutenchamon in Egypt. Modern light alloy wheels of commercial vehicles reach values up to 160 kg/kg. Additionally the comlex design of the modern systems for cars and commercial vehicles comprising wheel, brake, hub, bearing, spindle and hub carrier, including different materials and their treatment, fasteners, press-fits, require an appropriate testing procedure. The variable loading conditions, caused by operational wheel forces, brake and torque moments including heating, may result in changing tolerances and press-fits during operation and consequently in different damage mechanisms. This can be simulated in the Biaxial Wheel Test Machine, whereby corresponding load programs are necessary. An overview about all biaxial test machines in usage at the end of 1999 is shown in the introduction. The total number is 17 for cars, 7 for commercial vehicles and 1 for trains. The six presentations of this meeting were consequently concentrated on: (a) recommendations for a standardization of load programs of the German Wheel Committee, (b) the simulation of brake and torque events and (c) the possibility for a numerical stress analyses and fatigue life assessment. (orig./AKF)

  1. Influence of polygonal wear of railway wheels on the wheel set axle stress

    Science.gov (United States)

    Wu, Xingwen; Chi, Maoru; Wu, Pingbo

    2015-11-01

    The coupled vehicle/track dynamic model with the flexible wheel set was developed to investigate the effects of polygonal wear on the dynamic stresses of the wheel set axle. In the model, the railway vehicle was modelled by the rigid multibody dynamics. The wheel set was established by the finite element method to analyse the high-frequency oscillation and dynamic stress of wheel set axle induced by the polygonal wear based on the modal stress recovery method. The slab track model was taken into account in which the rail was described by the Timoshenko beam and the three-dimensional solid finite element was employed to establish the concrete slab. Furthermore, the modal superposition method was adopted to calculate the dynamic response of the track. The wheel/rail normal forces and the tangent forces were, respectively, determined by the Hertz nonlinear contact theory and the Shen-Hedrick-Elkins model. Using the coupled vehicle/track dynamic model, the dynamic stresses of wheel set axle with consideration of the ideal polygonal wear and measured polygonal wear were investigated. The results show that the amplitude of wheel/rail normal forces and the dynamic stress of wheel set axle increase as the vehicle speeds rise. Moreover, the impact loads induced by the polygonal wear could excite the resonance of wheel set axle. In the resonance region, the amplitude of the dynamic stress for the wheel set axle would increase considerably comparing with the normal conditions.

  2. Theoretical considerations of machining with grinding wheels

    Directory of Open Access Journals (Sweden)

    Andrew Oyakhobo Odior

    2013-03-01

    Full Text Available Grinding is one of the most versatile methods of removing material from machine parts by the cutting action of the countless hard and sharp abrasive particles of a revolving grinding wheel. It works by forcing the abrasive grains into the surface of the workpiece so that each grain cuts away a small bit of material in the form of chips. Abrasive grinding wheel is an expendable wheel that carries an abrasive compound on its periphery. They are made of small, sharp and very hard natural or synthetic abrasive minerals, bonded together in a matrix to form a wheel. The paper presents a review of some of the characteristics as well as theoretical considerations of operations of abrasive grinding wheel. The relationships among the various grinding parameters; the radial force f, the force on individual grit of grinding wheel F, velocity of grinding wheelg Vg, velocity of work piecew Vw, the wheel diameterg Dg, and the diameter of the work piece Dw were established for given grinding operations.

  3. Minisatellite Attitude Guidance Using Reaction Wheels

    Directory of Open Access Journals (Sweden)

    Ion STROE

    2015-06-01

    Full Text Available In a previous paper [2], the active torques needed for the minisatellite attitude guidance from one fixed attitude posture to another fixed attitude posture were determined using an inverse dynamics method. But when considering reaction/momentum wheels, instead of this active torques computation, the purpose is to compute the angular velocities of the three reaction wheels which ensure the minisatellite to rotate from the initial to the final attitude. This paper presents this computation of reaction wheels angular velocities using a similar inverse dynamics method based on inverting Euler’s equations of motion for a rigid body with one fixed point, written in the framework of the x-y-z sequence of rotations parameterization. For the particular case A=B not equal C of an axisymmetric minisatellite, the two computations are compared: the active torques computation versus the computation of reaction wheels angular velocities ̇x , ̇y and ̇z. An interesting observation comes out from this numerical study: if the three reaction wheels are identical (with Iw the moment of inertia of one reaction wheel with respect to its central axis, then the evolutions in time of the products between Iw and the derivatives of the reaction wheels angular velocities, i.e. ̇ , ̇ and ̇ remain the same and do not depend on the moment of inertia Iw.

  4. Loading and damageability of wheels and rails

    Directory of Open Access Journals (Sweden)

    George TUMANISHVILI

    2009-01-01

    Full Text Available Friction, rolling resistance and durability of rails and wheels at operation, belong to a number of the most important problems of railway transportation because they have strong impact on derailment, energy consumption and restorative maintenance. Various aspects of these problems are insufficiently investigated, have only partial solution. The sources of creep and slipping of a wheel on a rail and ways of its reduction are specified in the work. These approaches alongside with the traditional methods (lubrication, radial steering bogie, etc. will ensure the reduction both the power and the thermal loading of the contact zone and wear rate of rails and wheels.

  5. Quantum mechanics & the big world

    NARCIS (Netherlands)

    Wezel, Jasper van

    2007-01-01

    Quantum Mechanics is one of the most successful physical theories of the last century. It explains physical phenomena from the smallest to the largest lengthscales. Despite this triumph, quantum mechanics is often perceived as a mysterious theory, involving superposition states that are alien to our

  6. Study Shows Just How Big a Role Cellphones Play in Car Crashes

    Science.gov (United States)

    ... Just How Big a Role Cellphones Play in Car Crashes In-vehicle videos highlight other distractions, such as ... the wheel, researchers report that video taken inside cars showed drivers were ... of crashes. Not surprisingly, the findings link cellphone use to ...

  7. 29 CFR 1910.215 - Abrasive wheel machinery.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 5 2010-07-01 2010-07-01 false Abrasive wheel machinery. 1910.215 Section 1910.215 Labor... OCCUPATIONAL SAFETY AND HEALTH STANDARDS Machinery and Machine Guarding § 1910.215 Abrasive wheel machinery. (a... wheel in motion. (5) Excluded machinery. Natural sandstone wheels and metal, wooden, cloth, or...

  8. FameLab International Final: a triumph for Switzerland and CERN

    CERN Document Server

    CERN Bulletin

    2015-01-01

    Oskari Vinko, from ETH Zurich, who won the Swiss finals organised at CERN last May, is the winner of the 2015 FameLab competition. The CERN winner Lillian Smestad, member of the AEgIS collaboration from the Norwegian Research Council, shared second place with François-Xavier Joly from France, who also was among the trainees at the FameLab Master Classes organised by CERN in April.     CERN's Lillian Smestad (left) and Oskari Vinko from ETH Zurich, during the Swiss and CERN joint final, organised at CERN in May 2015. The 2015 FameLab International Final, which took place on 4 June in Cheltenham, UK, was a triumph for Switzerland and CERN! The competition was very hard this year, with 27 countries participating in the international semifinals and only nine making it through to the finals. This was also the first year that CERN took part as a “country”.  Congratulations to all the winners! To experience the international Famelab ...

  9. [Fracture of the diaphyseal radius during Cyr wheel practice - an uncommon injury of wheel gymnastics].

    Science.gov (United States)

    Kauther, M D; Rummel, S; Hussmann, B; Lendemans, S; Nast-Kolb, D; Wedemeyer, C

    2011-12-01

    The cyr wheel is a modified gymnastic wheel with only one ring that can lead to extreme forces on the gymnast. We report on a distal radius shaft fracture (AO 22 A 2.1) and a fracture of the styloid process of the ulna that occurred after holding on to a slipping Cyr wheel and exposition to high pressure on the lower arm. The fracture was fixed by screws and a plate. PMID:22161268

  10. Characterizing Big Data Management

    OpenAIRE

    Rogério Rossi; Kechi Hirama

    2015-01-01

    Big data management is a reality for an increasing number of organizations in many areas and represents a set of challenges involving big data modeling, storage and retrieval, analysis and visualization. However, technological resources, people and processes are crucial to facilitate the management of big data in any kind of organization, allowing information and knowledge from a large volume of data to support decision-making. Big data management can be supported by these three dimensions: t...

  11. The Influence of Wheel/Rail Contact Conditions on the Microstructure and Hardness of Railway Wheels

    Directory of Open Access Journals (Sweden)

    Paul Molyneux-Berry

    2014-01-01

    Full Text Available The susceptibility of railway wheels to wear and rolling contact fatigue damage is influenced by the properties of the wheel material. These are influenced by the steel composition, wheel manufacturing process, and thermal and mechanical loading during operation. The in-service properties therefore vary with depth below the surface and with position across the wheel tread. This paper discusses the stress history at the wheel/rail contact (derived from dynamic simulations and observed variations in hardness and microstructure. It is shown that the hardness of an “in-service” wheel rim varies significantly, with three distinct effects. The underlying hardness trend with depth can be related to microstructural changes during manufacturing (proeutectoid ferrite fraction and pearlite lamellae spacing. The near-surface layer exhibits plastic flow and microstructural shear, especially in regions which experience high tangential forces when curving, with consequentially higher hardness values. Between 1 mm and 7 mm depth, the wheel/rail contacts cause stresses exceeding the material yield stress, leading to work hardening, without a macroscopic change in microstructure. These changes in material properties through the depth of the wheel rim would tend to increase the likelihood of crack initiation on wheels toward the end of their life. This correlates with observations from several train fleets.

  12. The influence of wheel/rail contact conditions on the microstructure and hardness of railway wheels.

    Science.gov (United States)

    Molyneux-Berry, Paul; Davis, Claire; Bevan, Adam

    2014-01-01

    The susceptibility of railway wheels to wear and rolling contact fatigue damage is influenced by the properties of the wheel material. These are influenced by the steel composition, wheel manufacturing process, and thermal and mechanical loading during operation. The in-service properties therefore vary with depth below the surface and with position across the wheel tread. This paper discusses the stress history at the wheel/rail contact (derived from dynamic simulations) and observed variations in hardness and microstructure. It is shown that the hardness of an "in-service" wheel rim varies significantly, with three distinct effects. The underlying hardness trend with depth can be related to microstructural changes during manufacturing (proeutectoid ferrite fraction and pearlite lamellae spacing). The near-surface layer exhibits plastic flow and microstructural shear, especially in regions which experience high tangential forces when curving, with consequentially higher hardness values. Between 1 mm and 7 mm depth, the wheel/rail contacts cause stresses exceeding the material yield stress, leading to work hardening, without a macroscopic change in microstructure. These changes in material properties through the depth of the wheel rim would tend to increase the likelihood of crack initiation on wheels toward the end of their life. This correlates with observations from several train fleets. PMID:24526883

  13. Cylindrical Wire Electrical Discharge Machining of Metal Bond Diamond Wheels- Part II: Wheel Wear Mechanism

    Energy Technology Data Exchange (ETDEWEB)

    McSpadden, SB

    2002-01-22

    The use of stereo scanning Electron Microscopy (SEM) to investigate the wear mechanism of the wire EDM true metal bond diamond wheel for ceramic grinding is presented. On the grinding wheel, a wedge-shape removal part was machined to enable the examination and measurement of the worn wheel surfaces using the stereo SEM. The stereo SEM was calibrated by comparing results of depth profile of a wear groove with the profilometer measurements. On the surface of the grinding wheel after wire EDM truing and before grinding, the diamond protruding heights were measured in the level of 35 {micro}m, comparing to the 54 {micro}m average size of the diamond in the grinding wheel. The gap between the EDM wire and rotating grinding wheel is estimated to be about 35 to 40 {micro}m. This observation indicates that, during the wire EDM, electrical sparks occur between the metal bond and EDM wire, which leaves the diamond protruding in the gap between the wire and wheel. The protruding diamond is immediately fractured at the start of the grinding process, even under a light grinding condition. After heavy grinding, the grinding wheel surface and the diamond protrusion heights are also investigated using the stereo SEM. The height of diamond protrusion was estimated in the 5 to 15 {micro}m range. This study has demonstrated the use of stereo SEM as a metrology tool to study the grinding wheel surface.

  14. Reaction Wheel with Embedded MEMS IMU Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Reaction wheels are used to stabilize satellites and to slew their orientation from object to object with precision and accuracy by varying the rotational speed of...

  15. Multiple Wheel Throwing: And Chess Sets.

    Science.gov (United States)

    Sapiro, Maurice

    1978-01-01

    A chess set project is suggested to teach multiple throwing, the creation on a potter's wheel of several pieces of similar configuration. Processes and finished sets are illustrated with photographs. (SJL)

  16. Mechanics of wheel-soil interaction

    Science.gov (United States)

    Houland, H. J.

    1973-01-01

    An approximate theory for wheel-soil interaction is presented which forms the basis for a practical solution to the problem. It is shown that two fundamental observations render the problem determinate: (1) The line of action of the resultant of radial stresses acting at the wheel soil interface approximately bisects the wheel-soil contact angle for all values of slip. (2) A shear stress surface can be hypothesized. The influence of soil inertia forces is also evaluated. A concept of equivalent cohesion is introduced which allows a convenient experimental comparison for both cohesive and frictional soils. This theory compares favorably with previous analyses and experimental data, and shows that soil inertia forces influencing the motion of a rolling wheel can be significant.

  17. Reaction Wheel Disturbance Model Extraction Software Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Reaction wheel mechanical noise is one of the largest sources of disturbance forcing on space-based observatories. Such noise arises from mass imbalance, bearing...

  18. Social big data mining

    CERN Document Server

    Ishikawa, Hiroshi

    2015-01-01

    Social Media. Big Data and Social Data. Hypotheses in the Era of Big Data. Social Big Data Applications. Basic Concepts in Data Mining. Association Rule Mining. Clustering. Classification. Prediction. Web Structure Mining. Web Content Mining. Web Access Log Mining, Information Extraction and Deep Web Mining. Media Mining. Scalability and Outlier Detection.

  19. Five Big Ideas

    Science.gov (United States)

    Morgan, Debbie

    2012-01-01

    Designing quality continuing professional development (CPD) for those teaching mathematics in primary schools is a challenge. If the CPD is to be built on the scaffold of five big ideas in mathematics, what might be these five big ideas? Might it just be a case of, if you tell me your five big ideas, then I'll tell you mine? Here, there is…

  20. Improved Squeaky Wheel Optimisation for Driver Scheduling

    OpenAIRE

    Aickelin, Uwe; Burke, Edmund; Li, Jingpeng

    2006-01-01

    This paper presents a technique called Improved Squeaky Wheel Optimisation (ISWO) for driver scheduling problems. It improves the original Squeaky Wheel Optimisation’s (SWO) effectiveness and execution speed by incorporating two additional steps of Selection and Mutation which implement evolution within a single solution. In the ISWO, a cycle of Analysis-Selection-Mutation-Prioritization-Construction continues until stopping conditions are reached. The Analysis step first computes the fitness...

  1. Minisatellite Attitude Guidance Using Reaction Wheels

    OpenAIRE

    Ion STROE; Dan N. Dumitriu

    2015-01-01

    In a previous paper [2], the active torques needed for the minisatellite attitude guidance from one fixed attitude posture to another fixed attitude posture were determined using an inverse dynamics method. But when considering reaction/momentum wheels, instead of this active torques computation, the purpose is to compute the angular velocities of the three reaction wheels which ensure the minisatellite to rotate from the initial to the final attitude. This paper presents this computation of ...

  2. Roulette-wheel selection via stochastic acceptance

    OpenAIRE

    Lipowski, Adam; Lipowska, Dorota

    2011-01-01

    Roulette-wheel selection is a frequently used method in genetic and evolutionary algorithms or in modeling of complex networks. Existing routines select one of N individuals using search algorithms of O(N) or O(log(N)) complexity. We present a simple roulette-wheel selection algorithm, which typically has O(1) complexity and is based on stochastic acceptance instead of searching. We also discuss a hybrid version, which might be suitable for highly heterogeneous weight distributions, found, fo...

  3. Aerodynamic analysis of an isolated vehicle wheel

    International Nuclear Information System (INIS)

    Increasing fuel prices force the manufacturers to look into all aspects of car aerodynamics including wheels, tyres and rims in order to minimize their drag. By diminishing the aerodynamic drag of vehicle the fuel consumption will decrease, while driving safety and comfort will improve. In order to properly illustrate the impact of a rotating wheel aerodynamics on the car body, precise analysis of an isolated wheel should be performed beforehand. In order to represent wheel rotation in contact with the ground, presented CFD simulations included Moving Wall boundary as well as Multiple Reference Frame should be performed. Sliding mesh approach is favoured but too costly at the moment. Global and local flow quantities obtained during simulations were compared to an experiment in order to assess the validity of the numerical model. Results of investigation illustrates dependency between type of simulation and coefficients (drag and lift). MRF approach proved to be a better solution giving result closer to experiment. Investigation of the model with contact area between the wheel and the ground helps to illustrate the impact of rotating wheel aerodynamics on the car body.

  4. Fiber optic sensor system for detecting movement or position of a rotating wheel bearing

    Science.gov (United States)

    Veeser, Lynn R.; Rodriguez, Patrick J.; Forman, Peter R.; Monahan, Russell E.; Adler, Jonathan M.

    1997-01-01

    An improved fiber optic sensor system and integrated sensor bearing assembly for detecting movement or position of a rotating wheel bearing having a multi-pole tone ring which produces an alternating magnetic field indicative of movement and position of the rotating member. A magneto-optical material, such as a bismuth garnet iron (B.I.G.) crystal, having discrete magnetic domains is positioned in the vicinity of the tone ring so that the domains align themselves to the magnetic field generated by the tone ring. A single fiber optic cable, preferably single mode fiber, carries light generated by a source of light to the B.I.G. crystal. The light passes through the B.I.G. crystal and is refracted at domain boundaries in the crystal. The intensity of the refracted light is indicative of the amount of alignment of the domains and therefore the strength of the magnetic field. The refracted light is carried by the fiber optic cable to an optic receiver where the intensity is measured and an electrical signal is generated and sent to a controller indicating the frequency of the changes in light intensity and therefore the rotational speed of the rotating wheel bearing.

  5. Experimental investigations on desiccant wheels

    International Nuclear Information System (INIS)

    Experimental investigations on several commercially available and newly fabricated rotors are conducted in two different laboratories to evaluate performance trends. Experimental uncertainties are analysed and the parameters determining the rotor performance are investigated. It is found that the optimal rotation speed is lower for lithium chloride or compound rotors than for silica gel rotors. Higher regeneration air temperatures lead to higher dehumidification potentials at almost equal dehumidification efficiencies, but with increasing regeneration specific heat input and enthalpy changes of the process air. The influence of the regeneration air humidity was also notable and low relative humidities increase the dehumidification potential. Finally, the measurements show that rising water content in the ambient air causes the dehumidification capacity to rise, while the dehumidification efficiency is not much affected and both specific regeneration heat input and latent heat change of the process air decrease. For desiccant cooling applications in humid climates this is a positive trend. - Highlights: ► New experimental results on a range of desiccant wheels. ► High dehumidification capacities and low enthalpy changes for process air high water content. ► Higher regeneration temperature increases capacity, but lowers energy efficiency.

  6. Microsoft big data solutions

    CERN Document Server

    Jorgensen, Adam; Welch, John; Clark, Dan; Price, Christopher; Mitchell, Brian

    2014-01-01

    Tap the power of Big Data with Microsoft technologies Big Data is here, and Microsoft's new Big Data platform is a valuable tool to help your company get the very most out of it. This timely book shows you how to use HDInsight along with HortonWorks Data Platform for Windows to store, manage, analyze, and share Big Data throughout the enterprise. Focusing primarily on Microsoft and HortonWorks technologies but also covering open source tools, Microsoft Big Data Solutions explains best practices, covers on-premises and cloud-based solutions, and features valuable case studies. Best of all,

  7. Big data computing

    CERN Document Server

    Akerkar, Rajendra

    2013-01-01

    Due to market forces and technological evolution, Big Data computing is developing at an increasing rate. A wide variety of novel approaches and tools have emerged to tackle the challenges of Big Data, creating both more opportunities and more challenges for students and professionals in the field of data computation and analysis. Presenting a mix of industry cases and theory, Big Data Computing discusses the technical and practical issues related to Big Data in intelligent information management. Emphasizing the adoption and diffusion of Big Data tools and technologies in industry, the book i

  8. Mining "big data" using big data services

    OpenAIRE

    Reips, UD; Matzat, U Uwe

    2014-01-01

    While many colleagues within science are fed up with the “big data fad”, empirical analyses we conducted for the current editorial actually show an inconsistent picture: we use big data services to determine whether there really is an increase in writing about big data or even widespread use of the term. Google Correlate (http://www.google.com/trends/correlate/), the first free tool we are presenting here, doesn’t list the term, showing that number of searches for it are below an absolute min...

  9. Project considerations and design of systems for wheeling cogenerated power

    Energy Technology Data Exchange (ETDEWEB)

    Tessmer, R.G. Jr.; Boyle, J.R.; Fish, J.H. III; Martin, W.A.

    1994-08-01

    Wheeling electric power, the transmission of electricity not owned by an electric utility over its transmission lines, is a term not generally recognized outside the electric utility industry. Investigation of the term`s origin is intriguing. For centuries, wheel has been used to describe an entire machine, not just individual wheels within a machine. Thus we have waterwheel, spinning wheel, potter`s wheel and, for an automobile, wheels. Wheel as a verb connotes transmission or modification of forces and motion in machinery. With the advent of an understanding of electricity, use of the word wheel was extended to be transmission of electric power as well as mechanical power. Today, use of the term wheeling electric power is restricted to utility transmission of power that it doesn`t own. Cogeneration refers to simultaneous production of electric and thermal power from an energy source. This is more efficient than separate production of electricity and thermal power and, in many instances, less expensive.

  10. From Big Crunch to Big Bang

    OpenAIRE

    Khoury, Justin; Ovrut, Burt A.; Seiberg, Nathan; Steinhardt, Paul J.(Princeton Center for Theoretical Science, Princeton University, Princeton, NJ, 08544, USA); Turok, Neil

    2001-01-01

    We consider conditions under which a universe contracting towards a big crunch can make a transition to an expanding big bang universe. A promising example is 11-dimensional M-theory in which the eleventh dimension collapses, bounces, and re-expands. At the bounce, the model can reduce to a weakly coupled heterotic string theory and, we conjecture, it may be possible to follow the transition from contraction to expansion. The possibility opens the door to new classes of cosmological models. F...

  11. Reaction Wheel Disturbance Model Extraction Software - RWDMES

    Science.gov (United States)

    Blaurock, Carl

    2009-01-01

    The RWDMES is a tool for modeling the disturbances imparted on spacecraft by spinning reaction wheels. Reaction wheels are usually the largest disturbance source on a precision pointing spacecraft, and can be the dominating source of pointing error. Accurate knowledge of the disturbance environment is critical to accurate prediction of the pointing performance. In the past, it has been difficult to extract an accurate wheel disturbance model since the forcing mechanisms are difficult to model physically, and the forcing amplitudes are filtered by the dynamics of the reaction wheel. RWDMES captures the wheel-induced disturbances using a hybrid physical/empirical model that is extracted directly from measured forcing data. The empirical models capture the tonal forces that occur at harmonics of the spin rate, and the broadband forces that arise from random effects. The empirical forcing functions are filtered by a physical model of the wheel structure that includes spin-rate-dependent moments (gyroscopic terms). The resulting hybrid model creates a highly accurate prediction of wheel-induced forces. It accounts for variation in disturbance frequency, as well as the shifts in structural amplification by the whirl modes, as the spin rate changes. This software provides a point-and-click environment for producing accurate models with minimal user effort. Where conventional approaches may take weeks to produce a model of variable quality, RWDMES can create a demonstrably high accuracy model in two hours. The software consists of a graphical user interface (GUI) that enables the user to specify all analysis parameters, to evaluate analysis results and to iteratively refine the model. Underlying algorithms automatically extract disturbance harmonics, initialize and tune harmonic models, and initialize and tune broadband noise models. The component steps are described in the RWDMES user s guide and include: converting time domain data to waterfall PSDs (power spectral

  12. Wheeling rates evaluation using optimal power flows

    International Nuclear Information System (INIS)

    Wheeling is the transmission of electrical power and reactive power from a seller to a buyer through a transmission network owned by a third party. The wheeling rates are then the prices charged by the third party for the use of its network. This paper proposes and evaluates a strategy for pricing wheeling power using a pricing algorithm that in addition to the fuel cost for generation incorporates the optimal allocation of the transmission system operating cost, based on time-of-use pricing. The algorithm is implemented for the IEEE standard 14 and 30 bus system which involves solving a modified optimal power flow problem iteratively. The base of the proposed algorithm is the hourly spot price. The analysis spans a total time period of 24 hours. Unlike other algorithms that use DC models, the proposed model captures wheeling rates of both real and reactive power. Based on the evaluation, it was concluded that the model has the potential for wide application in calculating wheeling rates in a deregulated competitive power transmission environment. 9 refs., 3 tabs

  13. Brush-Wheel Samplers for Planetary Exploration

    Science.gov (United States)

    Rivellini, Tommaso

    2003-01-01

    A report proposes brush-wheel mechanisms for acquiring samples of soils from remote planets. In simplest terms, such a mechanism would contain brush wheels that would be counter-rotated at relatively high speed. The mechanism would be lowered to the ground from a spacecraft or other exploratory vehicle. Upon contact with the ground, the counter-rotating brush wheels would kick soil up into a collection chamber. Thus, in form and function, the mechanism would partly resemble traditional street and carpet sweepers. The main advantage of using of brush wheels (in contradistinction to cutting wheels or other, more complex mechanisms) is that upon encountering soil harder than expected, the brushes could simply deflect and the motor(s) could continue to turn. That is, sufficiently flexible brushes would afford resistance to jamming and to overloading of the motors used to rotate the brushes, and so the motors could be made correspondingly lighter and less power hungry. Of course, one could select the brush stiffnesses and motor torques and speeds for greatest effectiveness in sampling soil of a specific anticipated degree of hardness.

  14. Big fundamental groups: generalizing homotopy and big homotopy

    OpenAIRE

    Penrod, Keith

    2014-01-01

    The concept of big homotopy theory was introduced by J. Cannon and G. Conner using big intervals of arbitrarily large cardinality to detect big loops. We find, for each space, a canonical cardinal that is sufficient to detect all big loops and all big homotopies in the space.

  15. ANALYSIS OF BIG DATA

    OpenAIRE

    Anshul Sharma; Preeti Gulia

    2014-01-01

    Big Data is data that either is too large, grows too fast, or does not fit into traditional architectures. Within such data can be valuable information that can be discovered through data analysis [1]. Big data is a collection of complex and large data sets that are difficult to process and mine for patterns and knowledge using traditional database management tools or data processing and mining systems. Big Data is data whose scale, diversity and complexity require new architecture, technique...

  16. Matrix Big Brunch

    OpenAIRE

    Bedford, J; Papageorgakis, C.; Rodriguez-Gomez, D.; Ward, J.

    2007-01-01

    Following the holographic description of linear dilaton null Cosmologies with a Big Bang in terms of Matrix String Theory put forward by Craps, Sethi and Verlinde, we propose an extended background describing a Universe including both Big Bang and Big Crunch singularities. This belongs to a class of exact string backgrounds and is perturbative in the string coupling far away from the singularities, both of which can be resolved using Matrix String Theory. We provide a simple theory capable of...

  17. The big bang

    International Nuclear Information System (INIS)

    The paper concerns the 'Big Bang' theory of the creation of the Universe 15 thousand million years ago, and traces events which physicists predict occurred soon after the creation. Unified theory of the moment of creation, evidence of an expanding Universe, the X-boson -the particle produced very soon after the big bang and which vanished from the Universe one-hundredth of a second after the big bang, and the fate of the Universe, are all discussed. (U.K.)

  18. Bucket wheel excavators for varying mining conditions

    Energy Technology Data Exchange (ETDEWEB)

    Schachtschneider, H.; Seliger, E.

    1987-06-01

    TAKRAF bucket wheel excavators have proven their efficiency through the achievement of daily production rates in excess of 300,000 bcm, and have accomplished this under the most difficult geological and climatic conditions. Even heavy, plastic, very sticky clays, very abrasive soils, and rocky partings have been successfully mined with bucket wheel excavators. The use of BWEs to mine the hard coal deposits at the Ekibastus surface mine in the U.S.S.R., has broadened the field of application of these machines. Based on the experience gained in heavy-duty service, the bucket wheel excavators designed in the future will be capable of successfully coping with even more difficult site conditions.

  19. Summary big data

    CERN Document Server

    2014-01-01

    This work offers a summary of Cukier the book: "Big Data: A Revolution That Will Transform How we Live, Work, and Think" by Viktor Mayer-Schonberg and Kenneth. Summary of the ideas in Viktor Mayer-Schonberg's and Kenneth Cukier's book: " Big Data " explains that big data is where we use huge quantities of data to make better predictions based on the fact we identify patters in the data rather than trying to understand the underlying causes in more detail. This summary highlights that big data will be a source of new economic value and innovation in the future. Moreover, it shows that it will

  20. Evaluation of drilling mud dispersion models at SOEI Tier 1 sites : part 1 North Triumph, Fall 1999

    International Nuclear Information System (INIS)

    This report presents the results of a project in which the latest version of the benthic boundary layer transport (bblt) model was evaluated using existing observational data from drill sites at the Sable Offshore Energy Platform (SOEP) Tier 1 drill sites from 1998-1999 when water-based drilled muds were released into the environment. The bblt model was used to simulate the drift and dispersion of suspended drilling muds near North Triumph site south of Sable Island. The simulations focused on the presence of barium sulfate (BaSO4), or barite, a compound which has an impact on sea scallops. The model successfully reproduced the very low concentration observed during the Environmental Effects Monitoring program. It was also capable of predicting barite concentrations over the entire drilling program. Barite concentrations were greater than 100 μg per litre within a few kilometres of the rig. In order to validate this prediction, there were no EEM observations during periods of active drilling mud discharge. Comparisons with other bblt simulations at Hibernia suggest that dispersion at the North Triumph site was much higher than at Hibernia in a similar water depth on the northeast Grand Banks of Newfoundland. 24 refs., 6 tabs., 28 figs

  1. Wheels and Butterflies: Title, Structure, Cover Design

    OpenAIRE

    Gould, Warwick

    2015-01-01

    The gold-stamped heraldic design of Yeats’s Wheels and Butterflies (London: Macmillan, 1934; Wade 175), together with a colour to approximate to that of the cloth on that book, have been represented on the top board of the present volume. In Wheels and Butterflies that device was also replicated in black on the title-page. It was created by an unknown (and probably in-house) artist commissioned by Macmillan, working from photographs of masks by Hildo Van Krop for Vrouwe Emer’s Groote Strijd, ...

  2. Wheeled foot quadruped robot HITAN-I

    Institute of Scientific and Technical Information of China (English)

    Wang Pengfei; Sun Lining

    2006-01-01

    In view of the robot running environment, the structure of wheeled foot and quadruped are adopted in this robot system, which combines the priorities of both wheeled robot and legged robot. Based on CAN bus, the two-class robot control system using multiple controllers and drivers is constructed. At the same time, serial inverse kinematics of swaying leg and parallel inverse kinematics of supporting legs are analyzed independently. The forward gait and turning gait are planned and experiment image is given at last.

  3. Roulette-wheel selection via stochastic acceptance

    CERN Document Server

    Lipowski, Adam

    2011-01-01

    Roulette-wheel selection is a frequently used method in genetic or evolutionary algorithms. Existing routines select one of N individuals using search algorithms of O(N) or O(\\log N) complexity. We present a simple roulette-wheel selection algorithm that typically has O(1) complexity and is based on stochastic acceptance instead of searching. With minor modifications the algorithm might be also used for sampling with fitness being cut-off at a certain value or for sampling without replacement.

  4. Roulette-wheel selection via stochastic acceptance

    Science.gov (United States)

    Lipowski, Adam; Lipowska, Dorota

    2012-03-01

    Roulette-wheel selection is a frequently used method in genetic and evolutionary algorithms or in modeling of complex networks. Existing routines select one of N individuals using search algorithms of O(N) or O(logN) complexity. We present a simple roulette-wheel selection algorithm, which typically has O(1) complexity and is based on stochastic acceptance instead of searching. We also discuss a hybrid version, which might be suitable for highly heterogeneous weight distributions, found, for example, in some models of complex networks. With minor modifications, the algorithm might also be used for sampling with fitness cut-off at a certain value or for sampling without replacement.

  5. Evaluation of the 30 Ton CHA Crane Wheel Axle Modification

    International Nuclear Information System (INIS)

    An existing design for eccentric bushings was utilized and updated as necessary to accommodate minor adjustment as required to correct wheel alignment on the North West Idler wheel. The design is revised to install eccentric bushings on only one end

  6. Dual of big bang and big crunch

    International Nuclear Information System (INIS)

    Starting from the Janus solution and its gauge theory dual, we obtain the dual gauge theory description of the cosmological solution by the procedure of double analytic continuation. The coupling is driven either to zero or to infinity at the big-bang and big-crunch singularities, which are shown to be related by the S-duality symmetry. In the dual Yang-Mills theory description, these are nonsingular as the coupling goes to zero in the N=4 super Yang-Mills theory. The cosmological singularities simply signal the failure of the supergravity description of the full type IIB superstring theory

  7. Bliver big data til big business?

    DEFF Research Database (Denmark)

    Ritter, Thomas

    2015-01-01

    Danmark har en digital infrastruktur, en registreringskultur og it-kompetente medarbejdere og kunder, som muliggør en førerposition, men kun hvis virksomhederne gør sig klar til næste big data-bølge.......Danmark har en digital infrastruktur, en registreringskultur og it-kompetente medarbejdere og kunder, som muliggør en førerposition, men kun hvis virksomhederne gør sig klar til næste big data-bølge....

  8. "I Was Proud of Myself That I Didn't Give up and I Did It": Experiences of Pride and Triumph in Learning Science

    Science.gov (United States)

    Bellocchi, Alberto; Ritchie, Stephen M.

    2015-01-01

    The role that specific emotions, such as pride and triumph, play during instruction in science education is an under researched field of study. Emotions are recognized as central to learning yet little is known about the way in which they are produced in naturalistic settings, how emotions relate to classroom learning during interactions, and what…

  9. Bucket wheel excavators: variable mining equipment in the focus

    Energy Technology Data Exchange (ETDEWEB)

    Nies, G.; Jurisch, H. (Schwermaschinenbau Lauchhammerwerk AG, Lauchhammer (Germany). TAKRAF Tagebautechnik)

    1992-01-01

    Specifications and performance parameters of different types of bucket wheel excavators are given. Factors discussed include: bucket wheel power requirement, discharge of the bucket wheel boom, structure of the digging unit, variations in the loading units, and adaptation of the crawler vehicle. 15 figs., 4 refs.

  10. 14 CFR 23.745 - Nose/tail wheel steering.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Nose/tail wheel steering. 23.745 Section 23.745 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT... Landing Gear § 23.745 Nose/tail wheel steering. (a) If nose/tail wheel steering is installed, it must...

  11. 14 CFR 23.499 - Supplementary conditions for nose wheels.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Supplementary conditions for nose wheels... Structure Ground Loads § 23.499 Supplementary conditions for nose wheels. In determining the ground loads on nose wheels and affected supporting structures, and assuming that the shock absorbers and tires are...

  12. Big Ideas in Art

    Science.gov (United States)

    Day, Kathleen

    2008-01-01

    In this article, the author shares how she was able to discover some big ideas about art education. She relates how she found great ideas to improve her teaching from the book "Rethinking Curriculum in Art." She also shares how she designed a "Big Idea" unit in her class.

  13. Big data for health.

    Science.gov (United States)

    Andreu-Perez, Javier; Poon, Carmen C Y; Merrifield, Robert D; Wong, Stephen T C; Yang, Guang-Zhong

    2015-07-01

    This paper provides an overview of recent developments in big data in the context of biomedical and health informatics. It outlines the key characteristics of big data and how medical and health informatics, translational bioinformatics, sensor informatics, and imaging informatics will benefit from an integrated approach of piecing together different aspects of personalized information from a diverse range of data sources, both structured and unstructured, covering genomics, proteomics, metabolomics, as well as imaging, clinical diagnosis, and long-term continuous physiological sensing of an individual. It is expected that recent advances in big data will expand our knowledge for testing new hypotheses about disease management from diagnosis to prevention to personalized treatment. The rise of big data, however, also raises challenges in terms of privacy, security, data ownership, data stewardship, and governance. This paper discusses some of the existing activities and future opportunities related to big data for health, outlining some of the key underlying issues that need to be tackled. PMID:26173222

  14. Steady state modeling of desiccant wheels

    DEFF Research Database (Denmark)

    Bellemo, Lorenzo; Elmegaard, Brian; Kærn, Martin Ryhl;

    2014-01-01

    Desiccant wheels are rotary desiccant dehumidifiers used in air conditioning and drying applications. The modeling of simultaneous heat and mass transfer in these components is crucial for estimating their performances, as well as for simulating and optimizing their implementation in complete...

  15. The time has come for retail wheeling

    International Nuclear Information System (INIS)

    Retail wheeling, the transmission and distribution of electric power for end users, fosters competition and promotes the efficient use of resources. Access to electric-utility transmission and distribution systems would establish competitive electric markets by permitting retail customers to obtain the lowest cost for energy which would meet their specific needs. Among electric utilities and their customers, the idea of allowing market forces to attract supply and set prices is a current controversy. To counter the anticompetitive effects of recent mergers in the wholesale market, the Federal Energy Regulatory Commission (FERC) has mandated open transmission access for wholesale customers. However, the FERC denied access to retail customers and qualifying facilities (QF) in both its Northeast Utilities (FERC case No. EC-90-1 90) and PacifiCorp (U.S. Circuit Court of Appeals for D.C., 89-1333) decisions. Retail wheeling will benefit both consumers and producers. The ability of large customers to purchase power from the lowest cost sources and have it transmitted to their facilities, will save American industrial and commercial customers at least $15 billion annually. The Increased efficiency resulting from competition would also reduce residential electric bills. Through retail wheeling, independent power producers can market their capacity to a greater customer base, and traditional utilities will benefit from access to other utilities markets with the more efficient utilities prospering. Retail wheeling will, therefore, reward efficient utilities and encourage inefficient utilities to improve

  16. Before the Outline--The Writing Wheel.

    Science.gov (United States)

    Rae, Colleen

    1986-01-01

    To help students write more effectively, a technique for writing from thesis statements is described that requires students to create a picture of a wheel. The hub is a word that is the essence of the topic; the spokes are concrete examples; and the tire is the thesis statement. (MLW)

  17. Rolling Friction on a Wheeled Laboratory Cart

    Science.gov (United States)

    Mungan, Carl E.

    2012-01-01

    A simple model is developed that predicts the coefficient of rolling friction for an undriven laboratory cart on a track that is approximately independent of the mass loaded onto the cart and of the angle of inclination of the track. The model includes both deformation of the wheels/track and frictional torque at the axles/bearings. The concept of…

  18. Big Data, Big Knowledge: Big Data for Personalized Healthcare.

    OpenAIRE

    Viceconti, M.; Hunter, P.; Hose, R.

    2015-01-01

    The idea that the purely phenomenological knowledge that we can extract by analyzing large amounts of data can be useful in healthcare seems to contradict the desire of VPH researchers to build detailed mechanistic models for individual patients. But in practice no model is ever entirely phenomenological or entirely mechanistic. We propose in this position paper that big data analytics can be successfully combined with VPH technologies to produce robust and effective in silico medicine soluti...

  19. Big data, big knowledge: big data for personalized healthcare.

    Science.gov (United States)

    Viceconti, Marco; Hunter, Peter; Hose, Rod

    2015-07-01

    The idea that the purely phenomenological knowledge that we can extract by analyzing large amounts of data can be useful in healthcare seems to contradict the desire of VPH researchers to build detailed mechanistic models for individual patients. But in practice no model is ever entirely phenomenological or entirely mechanistic. We propose in this position paper that big data analytics can be successfully combined with VPH technologies to produce robust and effective in silico medicine solutions. In order to do this, big data technologies must be further developed to cope with some specific requirements that emerge from this application. Such requirements are: working with sensitive data; analytics of complex and heterogeneous data spaces, including nontextual information; distributed data management under security and performance constraints; specialized analytics to integrate bioinformatics and systems biology information with clinical observations at tissue, organ and organisms scales; and specialized analytics to define the "physiological envelope" during the daily life of each patient. These domain-specific requirements suggest a need for targeted funding, in which big data technologies for in silico medicine becomes the research priority. PMID:26218867

  20. BigDog

    Science.gov (United States)

    Playter, R.; Buehler, M.; Raibert, M.

    2006-05-01

    BigDog's goal is to be the world's most advanced quadruped robot for outdoor applications. BigDog is aimed at the mission of a mechanical mule - a category with few competitors to date: power autonomous quadrupeds capable of carrying significant payloads, operating outdoors, with static and dynamic mobility, and fully integrated sensing. BigDog is about 1 m tall, 1 m long and 0.3 m wide, and weighs about 90 kg. BigDog has demonstrated walking and trotting gaits, as well as standing up and sitting down. Since its creation in the fall of 2004, BigDog has logged tens of hours of walking, climbing and running time. It has walked up and down 25 & 35 degree inclines and trotted at speeds up to 1.8 m/s. BigDog has walked at 0.7 m/s over loose rock beds and carried over 50 kg of payload. We are currently working to expand BigDog's rough terrain mobility through the creation of robust locomotion strategies and terrain sensing capabilities.

  1. Big Data in industry

    Science.gov (United States)

    Latinović, T. S.; Preradović, D. M.; Barz, C. R.; Latinović, M. T.; Petrica, P. P.; Pop-Vadean, A.

    2016-08-01

    The amount of data at the global level has grown exponentially. Along with this phenomena, we have a need for a new unit of measure like exabyte, zettabyte, and yottabyte as the last unit measures the amount of data. The growth of data gives a situation where the classic systems for the collection, storage, processing, and visualization of data losing the battle with a large amount, speed, and variety of data that is generated continuously. Many of data that is created by the Internet of Things, IoT (cameras, satellites, cars, GPS navigation, etc.). It is our challenge to come up with new technologies and tools for the management and exploitation of these large amounts of data. Big Data is a hot topic in recent years in IT circles. However, Big Data is recognized in the business world, and increasingly in the public administration. This paper proposes an ontology of big data analytics and examines how to enhance business intelligence through big data analytics as a service by presenting a big data analytics services-oriented architecture. This paper also discusses the interrelationship between business intelligence and big data analytics. The proposed approach in this paper might facilitate the research and development of business analytics, big data analytics, and business intelligence as well as intelligent agents.

  2. Big data a primer

    CERN Document Server

    Bhuyan, Prachet; Chenthati, Deepak

    2015-01-01

    This book is a collection of chapters written by experts on various aspects of big data. The book aims to explain what big data is and how it is stored and used. The book starts from  the fundamentals and builds up from there. It is intended to serve as a review of the state-of-the-practice in the field of big data handling. The traditional framework of relational databases can no longer provide appropriate solutions for handling big data and making it available and useful to users scattered around the globe. The study of big data covers a wide range of issues including management of heterogeneous data, big data frameworks, change management, finding patterns in data usage and evolution, data as a service, service-generated data, service management, privacy and security. All of these aspects are touched upon in this book. It also discusses big data applications in different domains. The book will prove useful to students, researchers, and practicing database and networking engineers.

  3. Recht voor big data, big data voor recht

    NARCIS (Netherlands)

    Lafarre, Anne

    2016-01-01

    Big data is een niet meer weg te denken fenomeen in onze maatschappij. Het is de hype cycle voorbij en de eerste implementaties van big data-technieken worden uitgevoerd. Maar wat is nu precies big data? Wat houden de vijf V's in die vaak genoemd worden in relatie tot big data? Ter inleiding van dez

  4. Assessing Big Data

    DEFF Research Database (Denmark)

    Leimbach, Timo; Bachlechner, Daniel

    2015-01-01

    In recent years, big data has been one of the most controversially discussed technologies in terms of its possible positive and negative impact. Therefore, the need for technology assessments is obvious. This paper first provides, based on the results of a technology assessment study, an overview...... of the potential and challenges associated with big data and then describes the problems experienced during the study as well as methods found helpful to address them. The paper concludes with reflections on how the insights from the technology assessment study may have an impact on the future governance of big...... data....

  5. Big bang nucleosynthesis

    International Nuclear Information System (INIS)

    The precision of measurements in modern cosmology has made huge strides in recent years, with measurements of the cosmic microwave background and the determination of the Hubble constant now rivaling the level of precision of the predictions of big bang nucleosynthesis. However, these results are not necessarily consistent with the predictions of the Standard Model of big bang nucleosynthesis. Reconciling these discrepancies may require extensions of the basic tenets of the model, and possibly of the reaction rates that determine the big bang abundances

  6. Big data for dummies

    CERN Document Server

    Hurwitz, Judith; Halper, Fern; Kaufman, Marcia

    2013-01-01

    Find the right big data solution for your business or organization Big data management is one of the major challenges facing business, industry, and not-for-profit organizations. Data sets such as customer transactions for a mega-retailer, weather patterns monitored by meteorologists, or social network activity can quickly outpace the capacity of traditional data management tools. If you need to develop or manage big data solutions, you'll appreciate how these four experts define, explain, and guide you through this new and often confusing concept. You'll learn what it is, why it m

  7. Numerical analysis of small recessed silicon carbide grinding wheels

    Directory of Open Access Journals (Sweden)

    M.J. Jackson

    2010-11-01

    Full Text Available Purpose: Silicon carbide grinding wheels are tools used in manufacturing industry to form precision componentsand continue to be used to increase production rates due to their ability to remove high volumes of material athigh speeds. There is a demand to increase the speed of rotation of the grinding wheel in order to achieve highremoval rates. The increase in speed creates a situation where the grinding machine and the operator are subjectedto a possible catastrophic failure of the wheel due to the stresses generated in the coarse brittle structure of thevitrified grinding wheel. The study focused on building and analyzing computer models of grinding wheels withrecessed features spinning at different rotational speeds. By employing a computational approach, it was possibleto determine the maximum principal stresses in the wheel together with the location of the stresses. The geometryof vitrified wheels considered included a plain-sided rotating wheel and a recessed rotating wheel.Design/methodology/approach: The paper shows how stresses and factors of safety are calculated in order topredict the bursting speeds of small recessed SiC grinding wheels. The main methods used include finite elementanalysis and mechanical testing of abrasive materials. The approach of the paper is to integrate the use of numericalanalysis techniques and experimental techniques to predict the safe operating conditions of SiC abrasive products.Findings: Calculations were conducted to determine maximum stress in parallel-sided and recessed cup wheels.Relevant factors of safety and bursting speed were also calculated and compared with experimental data. Thepaper proves the usefulness and applicability of a method developed for taking account of stress concentrationsat the recess of small cup-shaped silicon carbide grinding wheels.Research limitations/implications: The paper is limited to analyzing small recessed SiC grinding wheels.Further work should focus on large

  8. Wheel traffic effect on air-filled porosity and air permeability in a soil catena across the wheel rut

    DEFF Research Database (Denmark)

    Berisso, Feto Esimo; Schjønning, Per; Lamandé, Mathieu;

    than at the periphery of the wheel rut (0.4 m) or outside the wheel rut. At least one of these differences εa was significant at all soil depths . At all matric potentials, the ka was lowest at the periphery of the wheel rut and highest outside the wheel rut, with intermediate values inside the wheel...... catena running from center of the wheel rut to un wheeled part of the field ( 0, 20, 40, 50,60 and 400 cm horizontal distance). We measured water retention and air permeability (ka) at -30, -100 and -300 hPa matric potentials. At -100 hPa, we obtained consistently lower air filled under the wheel rut......The impact of wheel traffic on soil physical properties is usually quantified by randomly collecting soil cores at specific depths below the wheeled surface. However, modeling studies as well as few measurements indicated a non-uniform stress distribution in a catena across the wheel rut, which...

  9. The Big Bang Singularity

    Science.gov (United States)

    Ling, Eric

    The big bang theory is a model of the universe which makes the striking prediction that the universe began a finite amount of time in the past at the so called "Big Bang singularity." We explore the physical and mathematical justification of this surprising result. After laying down the framework of the universe as a spacetime manifold, we combine physical observations with global symmetrical assumptions to deduce the FRW cosmological models which predict a big bang singularity. Next we prove a couple theorems due to Stephen Hawking which show that the big bang singularity exists even if one removes the global symmetrical assumptions. Lastly, we investigate the conditions one needs to impose on a spacetime if one wishes to avoid a singularity. The ideas and concepts used here to study spacetimes are similar to those used to study Riemannian manifolds, therefore we compare and contrast the two geometries throughout.

  10. Big Data Analytics

    Indian Academy of Sciences (India)

    2016-08-01

    The volume and variety of data being generated using computersis doubling every two years. It is estimated that in 2015,8 Zettabytes (Zetta=1021) were generated which consistedmostly of unstructured data such as emails, blogs, Twitter,Facebook posts, images, and videos. This is called big data. Itis possible to analyse such huge data collections with clustersof thousands of inexpensive computers to discover patterns inthe data that have many applications. But analysing massiveamounts of data available in the Internet has the potential ofimpinging on our privacy. Inappropriate analysis of big datacan lead to misleading conclusions. In this article, we explainwhat is big data, how it is analysed, and give some case studiesillustrating the potentials and pitfalls of big data analytics.

  11. Reframing Open Big Data

    DEFF Research Database (Denmark)

    Marton, Attila; Avital, Michel; Jensen, Tina Blegind

    2013-01-01

    ’, these developments introduce an unprecedented level of societal and organizational engagement with the potential of computational data to generate new insights and information. Based on the commonalities shared by open data and big data, we develop a research framework that we refer to as open big data (OBD......Recent developments in the techniques and technologies of collecting, sharing and analysing data are challenging the field of information systems (IS) research let alone the boundaries of organizations and the established practices of decision-making. Coined ‘open data’ and ‘big data......) by employing the dimensions of ‘order’ and ‘relationality’. We argue that these dimensions offer a viable approach for IS research on open and big data because they address one of the core value propositions of IS; i.e. how to support organizing with computational data. We contrast these dimensions with two...

  12. Big Creek Pit Tags

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The BCPITTAGS database is used to store data from an Oncorhynchus mykiss (steelhead/rainbow trout) population dynamics study in Big Creek, a coastal stream along...

  13. Big data opportunities and challenges

    CERN Document Server

    2014-01-01

    This ebook aims to give practical guidance for all those who want to understand big data better and learn how to make the most of it. Topics range from big data analysis, mobile big data and managing unstructured data to technologies, governance and intellectual property and security issues surrounding big data.

  14. Sharing big biomedical data

    OpenAIRE

    Toga, Arthur W.; Dinov, Ivo D.

    2015-01-01

    Background The promise of Big Biomedical Data may be offset by the enormous challenges in handling, analyzing, and sharing it. In this paper, we provide a framework for developing practical and reasonable data sharing policies that incorporate the sociological, financial, technical and scientific requirements of a sustainable Big Data dependent scientific community. Findings Many biomedical and healthcare studies may be significantly impacted by using large, heterogeneous and incongruent data...

  15. Testing Big Bang Nucleosynthesis

    OpenAIRE

    Steigman, Gary

    1996-01-01

    Big Bang Nucleosynthesis (BBN), along with the cosmic background radiation and the Hubble expansion, is one of the pillars ofthe standard, hot, big bang cosmology since the primordial synthesis of the light nuclides (D, $^3$He, $^4$He, $^7$Li) must have occurred during the early evolution of a universe described by this model. The overall consistency between the predicted and observed abundances of the light nuclides, each of which spans a range of some nine orders of magnitude, provides impr...

  16. Minsky on "Big Government"

    Directory of Open Access Journals (Sweden)

    Daniel de Santana Vasconcelos

    2014-03-01

    Full Text Available This paper objective is to assess, in light of the main works of Minsky, his view and analysis of what he called the "Big Government" as that huge institution which, in parallels with the "Big Bank" was capable of ensuring stability in the capitalist system and regulate its inherently unstable financial system in mid-20th century. In this work, we analyze how Minsky proposes an active role for the government in a complex economic system flawed by financial instability.

  17. Big Bang baryosynthesis

    International Nuclear Information System (INIS)

    In these lectures I briefly review Big Bang baryosynthesis. In the first lecture I discuss the evidence which exists for the BAU, the failure of non-GUT symmetrical cosmologies, the qualitative picture of baryosynthesis, and numerical results of detailed baryosynthesis calculations. In the second lecture I discuss the requisite CP violation in some detail, further the statistical mechanics of baryosynthesis, possible complications to the simplest scenario, and one cosmological implication of Big Bang baryosynthesis. (orig./HSI)

  18. Conociendo Big Data

    Directory of Open Access Journals (Sweden)

    Juan José Camargo-Vega

    2014-12-01

    Full Text Available Teniendo en cuenta la importancia que ha adquirido el término Big Data, la presente investigación buscó estudiar y analizar de manera exhaustiva el estado del arte del Big Data; además, y como segundo objetivo, analizó las características, las herramientas, las tecnologías, los modelos y los estándares relacionados con Big Data, y por último buscó identificar las características más relevantes en la gestión de Big Data, para que con ello se pueda conocer todo lo concerniente al tema central de la investigación.La metodología utilizada incluyó revisar el estado del arte de Big Data y enseñar su situación actual; conocer las tecnologías de Big Data; presentar algunas de las bases de datos NoSQL, que son las que permiten procesar datos con formatos no estructurados, y mostrar los modelos de datos y las tecnologías de análisis de ellos, para terminar con algunos beneficios de Big Data.El diseño metodológico usado para la investigación fue no experimental, pues no se manipulan variables, y de tipo exploratorio, debido a que con esta investigación se empieza a conocer el ambiente del Big Data.

  19. Improved Squeaky Wheel Optimisation for Driver Scheduling

    CERN Document Server

    Aickelin, Uwe; Li, Jingpeng

    2008-01-01

    This paper presents a technique called Improved Squeaky Wheel Optimisation for driver scheduling problems. It improves the original Squeaky Wheel Optimisations effectiveness and execution speed by incorporating two additional steps of Selection and Mutation which implement evolution within a single solution. In the ISWO, a cycle of Analysis-Selection-Mutation-Prioritization-Construction continues until stopping conditions are reached. The Analysis step first computes the fitness of a current solution to identify troublesome components. The Selection step then discards these troublesome components probabilistically by using the fitness measure, and the Mutation step follows to further discard a small number of components at random. After the above steps, an input solution becomes partial and thus the resulting partial solution needs to be repaired. The repair is carried out by using the Prioritization step to first produce priorities that determine an order by which the following Construction step then schedul...

  20. Smart Wheel Chair for Visually Impaired

    Directory of Open Access Journals (Sweden)

    Dev Pratap Singh

    2014-08-01

    Full Text Available The visually impaired persons suffer from lack of confidence, restricted mobility and dependence on others in their daily life. This paper proposes an embedded system design of a smart wheel chair aiming for visually impaired using high-end technical tools like AVR Studio, ATMEGA 16 Development Board (Atmel Corporation, proximity sensors and DTMF Decoder. The movement of wheelchair is controlled by cellular phones specifically designed for the visually challenged people (Toshiba, Huawei, Sens are companies that manufacture such specific mobiles. In this paper existing designs of wheel chair are also discussed. In addition to being user-friendly, the proposed design also provides a high degree of mobility and defence against obstacles for the visually impaired. Further the design is also tested using Printed Circuit Board (PCB and the results obtained are in perfect accordance with the expectations. This proposed smart chair design outperforms the existing designs in terms of obstacle avoidance and technology.

  1. Advanced Control of Wheeled Inverted Pendulum Systems

    CERN Document Server

    Li, Zhijun; Fan, Liping

    2013-01-01

    Advanced Control of Wheeled Inverted Pendulum Systems is an orderly presentation of recent ideas for overcoming the complications inherent in the control of wheeled inverted pendulum (WIP) systems, in the presence of uncertain dynamics, nonholonomic kinematic constraints as well as underactuated configurations. The text leads the reader in a theoretical exploration of problems in kinematics,dynamics modeling, advanced control design techniques,and trajectory generation for WIPs. An important concern is how to deal with various uncertainties associated with the nominal model, WIPs being characterized by unstable balance and unmodelled dynamics and being subject to time-varying external disturbances for which accurate models are hard to come by.   The book is self-contained, supplying the reader with everything from mathematical preliminaries and the basic Lagrange-Euler-based derivation of dynamics equations to various advanced motion control and force control approaches as well as trajectory generation met...

  2. A magneto-electric quantum wheel

    OpenAIRE

    Feigel, Alexander

    2009-01-01

    Here we show that self-propulsion in quantum vacuum may be achieved by rotating or aggregating magneto-electric nano-particles. The back-action follows from changes in momentum of electro-magnetic zero-point fluctuations, generated in magneto-electric materials. This effect may provide new tools for investigation of the quantum nature of our world. It might also serve in the future as a "quantum wheel" to correct satellite orientation in space.

  3. Bucket wheel excavators VABE 550 in China

    Energy Technology Data Exchange (ETDEWEB)

    In June 1989, China National Machinery Import and Export Corporation (CNM Corp.) and Voest-Alpine Bergtechnik (VA-Bergteknik) signed a contract for the engineering and delivery of 3 bucket wheel excavators type VABE 550 to be used in a large open pit brown coal mine in Yunnan Province, P.R. China. This article provides technical data relating to the excavators and discusses the results of a performance test conducted after completion of erection and commissioning. 2 photos.

  4. Tram wheel modelling for dynamic analysis

    Czech Academy of Sciences Publication Activity Database

    Pešek, Luděk; Veselý, Jan; Podruh, J.

    Brno : SVS FEN s.r.o., 2003, s. 1-7. ISBN 80-239-1598-3. [ANSYS & STAR-CD Users' Meeting /11./. Znojmo (CZ), 25.09.2003-26.09.2003] R&D Projects: GA ČR GA101/02/0241 Institutional research plan: CEZ:AV0Z2076919 Keywords : tram wheel * experimental modal analysis Subject RIV: BI - Acoustics

  5. Hybrid uranyl-vanadium nano-wheels.

    Science.gov (United States)

    Senchyk, G A; Wylie, E M; Prizio, S; Szymanowski, J E S; Sigmon, G E; Burns, P C

    2015-06-25

    Hybrid uranyl-vanadium oxide clusters intermediate between transition metal polyoxometalates and uranyl peroxide cage clusters were obtained by dissolving uranyl nitrate in the ionic liquid 3-ethyl-1-methylimidazolium ethyl sulfate mixed with an aqueous solution containing vanadium. Where sulfate was present, wheel-shaped {U20V20} crystallized and contains ten sulfate tetrahedra, and in the absence of added sulfate, {U2V16}, a derivative of {V18}, was obtained. PMID:26008125

  6. Influence of wheel configuration on wheelchair basketball performance: wheel stiffness, tyre type and tyre orientation.

    Science.gov (United States)

    Mason, B S; Lemstra, M; van der Woude, L H V; Vegter, R; Goosey-Tolfrey, V L

    2015-04-01

    The aim of the current investigation was to explore the lateral stiffness of different sports wheelchair wheels available to athletes in 'new' and 'used' conditions and to determine the effect of (a) stiffness, (b) tyre type (clincher vs. tubular) and (c) tyre orientation on the physiological and biomechanical responses to submaximal and maximal effort propulsion specific to wheelchair basketball. Eight able-bodied individuals participated in the laboratory-based testing, which took place on a wheelchair ergometer at two fixed speeds (1.1 and 2.2 m s(-1)). Outcome measures were power output and physiological demand (oxygen uptake and heart rate). Three participants with experience of over-ground sports wheelchair propulsion also performed 2 × 20 m sprints in each wheel configuration. Results revealed that wheels differed significantly in lateral stiffness with the 'new' Spinergy wheel shown to be the stiffest (678.2 ± 102.1 N mm(-1)). However the effects of stiffness on physiological demand were minimal compared to tyre type whereby tubular tyres significantly reduced the rolling resistance and power output in relation to clincher tyres. Therefore tyre type (and subsequently inflation pressure) remains the most important aspect of wheel specification for athletes to consider and monitor when configuring a sports wheelchair. PMID:25726151

  7. Flow Visualization around a Simplified Two-Wheel Landing Gear

    Science.gov (United States)

    Ekmekci, Alis; Feltham, Graham

    2013-11-01

    The flow topology around a simplified two-wheel landing gear model is investigated experimentally by employing the hydrogen bubble flow visualization technique in a recirculating water channel. The landing gear test model consists of two identical wheels, an axle, a main strut and a support strut. The flow Reynolds number based on wheel diameter is 31,500 and wheels with varying geometric details are considered. Flow structures have been identified through analysis of long-time video recordings and linked to the model geometry. In the flow region above the wheels (wing side), the flow in the inter-wheel region either separates prematurely from the inner surfaces of the wheels and forms slant vortices in the near-wake, or remains attached till the aft wheel perimeter. Inclusion of interior wheel wells are found to result in a jet-like ejection as a result of the interaction with the axle and main strut. In the flow region below the wheels (ground side) the near wake contains periodically forming, complex, large-scale structures.

  8. Parametric analysis of wheel wear in high-speed vehicles

    Institute of Scientific and Technical Information of China (English)

    Na Wu; Jing Zeng

    2014-01-01

    In order to reduce the wheel profile wear of high-speed trains and extend the service life of wheels, a dynamic model for a high-speed vehicle was set up, in which the wheelset was regarded as flexible body, and the actual mea-sured track irregularities and line conditions were considered. The wear depth of the wheel profile was calculated by the well-known Archard wear law. Through this model, the influence of the wheel profile, primary suspension stiffness, track gage, and rail cant on the wear of wheel profile were studied through multiple iterative calculations. Numerical simulation results show that the type XP55 wheel profile has the smallest cumulative wear depth, and the type LM wheel profile has the largest wear depth. To reduce the wear of the wheel profile, the equivalent conicity of the wheel should not be too large or too small. On the other hand, a small primary vertical stiffness, a track gage around 1,435-1,438 mm, and a rail cant around 1:35-1:40 are beneficial for dynamic per-formance improvement and wheel wear alleviation.

  9. Rotating target wheel for the FMA

    Energy Technology Data Exchange (ETDEWEB)

    Back, B.B.; Davids, C.N.; Falout, J. [and others

    1995-08-01

    In anticipation of high intensity beams that will be available from the PII-ECR source injector to ATLAS, a new rotating target wheel was developed for the sliding seal chamber at the FMA. The wheel is 9 inch in diameter and contains up to ten targets. The rotation of the wheel is achieved by a DC motor, a ferrofluidic feedthrough, and a gear mechanism that allows both target rotation and changing the target angle relative to the beam. The nominal rotation speed is 1000 RPM, although higher speeds can be achieved if necessary. The assembly is equipped with an absolute encoder which is read out via a newly developed CAMAC module. This module provides the following main functions: (1) a TTL signal to be used for sweeping the beam when a target frame is about to pass through the beam, (2) a read-out of the target position that can be included in the data event structure, (3) programmable set points for the beam-off signal. The system is presently being tested and will be used in experiments scheduled for March 1995.

  10. Examination of the causes of a bucket wheel fracture in a bucket wheel excavator

    Energy Technology Data Exchange (ETDEWEB)

    Rusinski, E.; Harnatkiewicz, P.; Kowalczyk, M.; Moczko, P. [Wroclaw University of Technology, Wroclaw (Poland). Faculty of Mechanical Engineering

    2010-09-15

    A bucket wheel excavator failure occurred in a brown-coal mine. The failure was caused by a fractured shaft of the bucket wheel. An attempt to determine the causes of the bucket wheel shaft fracture has been made. To that end, the character of changing loads and their maximum amplitudes has been determined by performing measurements on the excavator. A discreet model of the shaft was built and a numerical simulation of the shaft operation using the FEM method was achieved. An analysis of the materials in the fracture area was also implemented. Macroscopic and microscopic images of the fracture area are provided. The shaft fracture was mainly caused by a non-metallic inclusion located below the surface of the shaft as a result of its being rolled. Moreover, it was discovered that the shaft had not been heat-treated.

  11. Problems of locomotive wheel wear in fleet replacement

    Directory of Open Access Journals (Sweden)

    L.P. Lingaytis

    2013-08-01

    Full Text Available Purpose. To conduct a research and find out the causes of defects appearing on the wheel thread of freight locomotives 2М62 and SIEMENS ER20CF. Methodology. To find the ways to solve this problem comparing the locomotive designs and their operating conditions. Findings. After examining the nature of the wheel wear the main difference was found: in locomotives of the 2M62 line wears the wheel flange, and in the locomotives SIEMENS ER20CF – the tread surface. After installation on the 2M62 locomotive the lubrication system of flanges their wear rate significantly decreased. On the new freight locomotives SIEMENS ER20CF the flange lubrication systems of the wheel set have been already installed at the factory, however the wheel thread is wearing. As for locomotives 2M62, and on locomotives SIEMENS ER20CF most wear profile skating wheels of the first wheel set. On both locomotive lines the 2М62 and the SIEMENS ER20CF the tread profile of the first wheel set most of all is subject to the wear. After reaching the 170 000 km run, the tread surface of some wheels begins to crumble. There was a suspicion that the reason for crumb formation of the wheel surface may be insufficient or excessive wheel hardness or its chemical composition. In order to confirm or deny this suspicion the following studies were conducted: the examination of the rim surface, the study of the wheel metal hardness and the document analysis of the wheel production and their comparison with the results of wheel hardness measurement. Practical value. The technical condition of locomotives is one of the bases of safety and reliability of the rolling stock. The reduction of the wheel wear significantly reduces the operating costs of railway transport. After study completion it was found that there was no evidence to suggest that the ratio of the wheel-rail hardness could be the cause of the wheel surface crumbling.

  12. OPTIMIZATION OF HEATING OF GEAR WHEEL USING NUMERICAL MODELING

    Directory of Open Access Journals (Sweden)

    Soňa Benešová

    2013-09-01

    Full Text Available Successful heat treating and carburizing of gear wheels for wind turbine gear boxes requires that plastic deformation in the wheel is minimized. Numerical modeling using the DEFORM software was aimed at exploring the effects of the base, on which the gear wheel rests during heating, on the heating process. Homogeneous heating was assumed. It was found that the base heats up more quickly than the workpiece. It is the consequence of the base's shape and volume. As a result, the base expands and slides against the wheel, predominantly at the first heating stage. Later on, it prevents the gear wheel from expanding, causing plastic deformation in the wheel. The findings were used for designing new heating schedules to minimize these undesirable interactions and to reduce the plastic deformation to a negligible magnitude. In addition, this paper presents an example of a practical use of numerical modeling in the DEFORM software.

  13. OPTIMIZATION OF HEATING OF GEAR WHEEL USING NUMERICAL MODELING

    Directory of Open Access Journals (Sweden)

    Sona Benesova

    2013-05-01

    Full Text Available Successful heat treating and carburizing of gear wheels for wind turbine gear boxes requires that plastic deformation in the wheel is minimized. Numerical modeling using the DEFORM software was aimed at exploring the effects of the base, on which the gear wheel rests during heating, on the heating process. Homogeneous heating was assumed. It was found that the base heats up more quickly than the workpiece. It is the consequence of the base's shape and volume. As a result, the base expands and slides against the wheel, predominantly at the first heating stage. Later on, it prevents the gear wheel from expanding, causing plastic deformation in the wheel. The findings were used for designing new heating schedules to minimize these undesirable interactions and to reduce the plastic deformation to a negligible magnitude. In addition, this paper presents an example of a practical use of numerical modeling in the DEFORM software.

  14. The colour wheels of art, perception, science and physiology

    Science.gov (United States)

    Harkness, Nick

    2006-06-01

    Colour is not the domain of any one discipline be it art, philosophy, psychology or science. Each discipline has its own colour wheel and this presentation examines the origins and philosophies behind the colour circles of Art, Perception, Science and Physiology (after image) with reference to Aristotle, Robert Boyle, Leonardo da Vinci, Goethe, Ewald Hering and Albert Munsell. The paper analyses and discusses the differences between the four colour wheels using the Natural Colour System® notation as the reference for hue (the position of colours within each of the colour wheels). Examination of the colour wheels shows the dominance of blue in the wheels of art, science and physiology particularly at the expense of green. This paper does not consider the three-dimensionality of colour space its goal was to review the hue of a colour with regard to its position on the respective colour wheels.

  15. A simulation model for risk assessment of turbine wheels

    Science.gov (United States)

    Safie, Fayssal M.; Hage, Richard T.

    A simulation model has been successfully developed to evaluate the risk of the Space Shuttle auxiliary power unit (APU) turbine wheels for a specific inspection policy. Besides being an effective tool for risk/reliability evaluation, the simulation model also allows the analyst to study the trade-offs between wheel reliability, wheel life, inspection interval, and rejection crack size. For example, in the APU application, sensitivity analysis results showed that the wheel life limit has the least effect on wheel reliability when compared to the effect of the inspection interval and the rejection crack size. In summary, the simulation model developed represents a flexible tool to predict turbine wheel reliability and study the risk under different inspection policies.

  16. Numerical and experimental analysis of a solid desiccant wheel

    OpenAIRE

    Koronaki Irene P.; Papoutsis Efstratios; Papaefthimiou Vassilis; Rogdakis Emmanouel

    2016-01-01

    The rotary desiccant dehumidifier is an important component which can be used in air conditioning systems in order to reduce the electrical energy consumption and introduce renewable energy sources. In this study a one dimensional gas side resistance model is presented for predicting the performance of the desiccant wheel. Measurements from two real sorption wheels are used in order to validate the model. One wheel uses silica gel as desiccant material and ...

  17. Evolución de Madurez en Pre y Postcosecha y Potencialidad de Almacenaje de Peras Packham's Triumph Pre and Post-Harvest Maturity Evolution and Storage Potential of Packham’s Triumph Pears

    Directory of Open Access Journals (Sweden)

    Claudia Moggia

    2005-09-01

    Full Text Available Peras (Pyrus communis L. Packham’s Triumph fueron evaluadas en madurez y producción de etileno desde cuatro semanas previo a la cosecha. Firmeza y sólidos solubles obtuvieron las mayores correlaciones (r = -0,97 y 0,98, respectivamente con días después de plena flor (DDPF. La producción de etileno fue baja (Packham’s Triumph pears (Pyrus communis L. were evaluated from four weeks before harvest for maturity and ethylene production. Firmness and soluble solids showed the highest correlations (r = -0.97 y 0.98, respectively with days after full bloom (DDPF. Ethylene production was low (< 0.07 mg kg-1 and was not correlated with DDPF. Fruit harvested with 7.8 (E1 and 7.0 kg (E2 were stored in conventional cold air (0°C and two controlled atmosphere conditions (AC1: 2-2.5% O2 /1-1.5% CO2 and AC2: 1-1.3% O2/0.5-0.8% CO2, -1°C, for six months. Changes in maturity, and ethylene production were measured (monthly and incidence of physiological disorders was assessed (after four and six months. Additionally, the ethylene production rate (TPE was monitored for seven days at room temperature, after each storage period. Fruit from both harvests, stored under AC1 and AC2 were firmer, greener and had lower ethylene production than those of FC. There were no significant differences in ripening between AC1 and AC2. Ethylene accumulation was exponential and occurred earlier and with higher values in FC (900 mg kg-1 maximum at the 5th month, with respect to AC (146 and 230 mg kg-1 for E1 and E2 at the end of the storage period. At room temperature, the TPE of the three storage conditions increased from the second month, but the climacteric peak was observed only in FC. After six months, fruit from FC and from both harvests developed superficial scald (17% for E1 and 20% for E2.

  18. MODELING AND STRUCTURAL ANALYSIS OF ALLOY WHEEL USING ANSYS

    OpenAIRE

    Mr. Sasank Shekhar Panda*; Mr. Dibya Narayan Behera; Mr. Satya Narayan Tripathy

    2016-01-01

    Wheel spokes are the supports consisting of a radial member of a wheel joining the hub to the rim with Carbon Fiber, Magnesium Alloy, Titanium Alloy and Aluminum Alloy. The two main types of motorcycle rims are solid wheels, in which case the rim and spokes are all cast as one unit, usually in Aluminum or magnesium alloys and the other spoke wheels, where the motorcycle rims are laced with spokes which require high spoke tension, since the load is carried by fewer spokes. If a spoke does brea...

  19. Big Data Revisited

    DEFF Research Database (Denmark)

    Kallinikos, Jannis; Constantiou, Ioanna

    2015-01-01

    We elaborate on key issues of our paper New games, new rules: big data and the changing context of strategy as a means of addressing some of the concerns raised by the paper’s commentators. We initially deal with the issue of social data and the role it plays in the current data revolution....... The massive involvement of lay publics as instrumented by social media breaks with the strong expert cultures that have underlain the production and use of data in modern organizations. It also sets apart the interactive and communicative processes by which social data is produced from sensor data...... and the technological recording of facts. We further discuss the significance of the very mechanisms by which big data is produced as distinct from the very attributes of big data, often discussed in the literature. In the final section of the paper, we qualify the alleged importance of algorithms and claim...

  20. Big Data and Peacebuilding

    Directory of Open Access Journals (Sweden)

    Sanjana Hattotuwa

    2013-11-01

    Full Text Available Any peace process is an exercise in the negotiation of big data. From centuries old communal hagiography to the reams of official texts, media coverage and social media updates, peace negotiations generate data. Peacebuilding and peacekeeping today are informed by, often respond and contribute to big data. This is no easy task. As recently as a few years ago, before the term big data embraced the virtual on the web, what informed peace process design and implementation was in the physical domain – from contested borders and resources to background information in the form of text. The move from analogue, face-to-face negotiations to online, asynchronous, web-mediated negotiations – which can still include real world meetings – has profound implications for how peace is strengthened in fragile democracies.

  1. Big data in biomedicine.

    Science.gov (United States)

    Costa, Fabricio F

    2014-04-01

    The increasing availability and growth rate of biomedical information, also known as 'big data', provides an opportunity for future personalized medicine programs that will significantly improve patient care. Recent advances in information technology (IT) applied to biomedicine are changing the landscape of privacy and personal information, with patients getting more control of their health information. Conceivably, big data analytics is already impacting health decisions and patient care; however, specific challenges need to be addressed to integrate current discoveries into medical practice. In this article, I will discuss the major breakthroughs achieved in combining omics and clinical health data in terms of their application to personalized medicine. I will also review the challenges associated with using big data in biomedicine and translational science. PMID:24183925

  2. Primordial Big Bang Nucleosynthesis

    OpenAIRE

    Olive, Keith A.

    1999-01-01

    Big Bang Nucleosynthesis is the theory of the production of the the light element isotopes of D, He3, He4, and Li7. After a brief review of the essential elements of the standard Big Bang model at a temperature of about 1 MeV, the theoretical input and predictions of BBN are discussed. The theory is tested by the observational determinations of the light element abundances and the current status of these observations is reviewed. Concordance of standard model and the related observations is f...

  3. Networks & big data

    OpenAIRE

    Litvak, Nelly; Meulen, van der, P.

    2015-01-01

    Once a year, the NWO cluster Stochastics – Theoretical and Applied Research (STAR) organises a STAR Outreach Day, a one-day event around a theme that is of a broad interest to the stochastics community in the Netherlands. The last Outreach Day took place at Eurandom on 12 December 2014. The theme of the day was ‘Networks & Big Data’. The topic is very timely. The Vision document 2025 of the PlatformWiskunde Nederland (PWN) mentions big data as one of the six “major societal and scientific tre...

  4. Wheel Torque Distribution of Four-Wheel-Drive Electric Vehicles Based on Multi-Objective Optimization

    Directory of Open Access Journals (Sweden)

    Cheng Lin

    2015-04-01

    Full Text Available The wheel driving torque on four-wheel-drive electric vehicles (4WDEVs can be modulated precisely and continuously, therefore maneuverability and energy-saving control can be carried out at the same time. In this paper, a wheel torque distribution strategy is developed based on multi-objective optimization to improve vehicle maneuverability and reduce energy consumption. In the high-layer of the presented method, sliding mode control is used to calculate the desired yaw moment due to the model inaccuracy and parameter error. In the low-layer, mathematical programming with the penalty function consisting of the yaw moment control offset, the drive system energy loss and the slip ratio constraint is used for wheel torque control allocation. The programming is solved with the combination of off-line and on-line optimization to reduce the calculation cost, and the optimization results are sent to motor controllers as torque commands. Co-simulation based on MATLAB® and Carsim® proves that the developed strategy can both improve the vehicle maneuverability and reduce energy consumption.

  5. REDUCING THE NEGATIVE INFLUENCE OF KINEMATIC DISCREPANCY IN THE TRANSMISSION OF FOUR-WHEEL DRIVE WHEELED VEHICLES

    Directory of Open Access Journals (Sweden)

    Ismailov V. A.

    2015-12-01

    Full Text Available The article discusses different types of drive axles of all-wheel drive machine. It is shown that if blocked drive of driving axle easy, it is able to provide the best traction drive qualities of the all-wheel car, if compensation of kinematic mismatch in movement of front and rear wheels. The article provides analysis of the causes of kinematic mismatch and its consequences. The analysis was given for the existing methods to reduce negative influence of kinematic discrepancy on the work of the four-wheel drive wheeled machine in locked mode. The method of reduction of kinematic mismatch by regulations of the air pressure in the tires of the wheels with one-time control of the leading moments on the axes was suggested. We show the relationship between the difference of kinematic radii of the wheels of different axles and the difference of the moments leading to them. The algorithm and description for the system of automatic control of air pressure in the tire, which realizes the proposed method, were presented. We have described experimental methods of determining the energy losses evaluation from kinematic mismatch when moving all-wheel drive machine. The article presents the results of the this assessment in relation to the agricultural wheel tractor of class 5 moving at different substructures

  6. The triumph and decline of the "squares": Grumman Aerospace engineers and production workers in the Apollo era, 1957--1973

    Science.gov (United States)

    Onkst, David Hugh

    This dissertation is a social, cultural, and economic history of the men and women of the Grumman Aerospace Company of Bethpage, New York from 1957 through 1973. These "Grummanites" were the engineers and production workers who designed and built the Apollo Lunar Modules that allowed humans to land on the Moon. This study provides unique insights into the impact that the Apollo Program---a large state-initiated and -supported program---had on those "squares," people whom many contemporaries saw as a vital part of mainstream 1960s American society. By the beginning of the Space Age in 1957, Grumman, Long Island's single largest employer, had firmly established a workplace culture of paternalism that Grummanites largely embraced. Company officials believed strongly in worker retention and had established a policy of providing every sort of benefit their employees seemingly desired, including a highly personal and participatory form of management. Many Grummanites had joined the firm during the early years of the Apollo Program because they believed in the promise of permanent employment on exciting projects that would explore the endless frontier of space. But, as many of these mainly self-reliant, individualistic "squares" would bitterly discover, their dedication to Grumman did little to secure their livelihoods during the aerospace industry's early 1970s downsizing; their individual successes were too largely tied to federal spending and declined when Americans grew disenchanted with space exploration. This dissertation demonstrates how the cultural bond of paternalism between aerospace workers and their company unraveled in the 1960s, and then ended in the early 1970s, because of forces within the company, the economy, and the American state. The word "triumph" in this study's title not only applies to Grummanites' triumphs with the Lunar Modules, but also their individual socioeconomic victories. The term "decline" refers to the early 1970s downsizing of more

  7. Strangulation--Suicide at the wheel.

    Science.gov (United States)

    Madea, Burkhard; Schmidt, Peter; Kernbach-Wighton, Gerhard; Doberentz, Elke

    2015-11-01

    In cases of suicide at the wheel mostly velocity is used to cause death by a single occupant vehicle crash against a fixed roadside object or collision with other vehicles. A further well known mode of death is e.g. carbon monoxide poisoning. In the recent years several cases of vehicle assisted ligature strangulation resulting even in decapitation have been reported. However, cars are also used in rare cases just as places for a suicide by hanging or ligature strangulation. Not only forensic pathologists but also police officers have to be aware of this rare type of suicide to avoid unnecessary investigations. PMID:26594000

  8. Analysis of Wheel Hubs : Student Car

    OpenAIRE

    Rincón García, Jesús

    2014-01-01

    The aim of this thesis work is to do the study and analysis of Student Car wheel hubs. The first part is a briefing of the “StudentCar” competition and a short explanation of the problem. Also it talks about the information and files that the team have about their hubs. After that, the document has short information about the basics knowledge of Strength of Materials necessary for to do the analysis in hubs and information about the material used by the team (Aluminum Alloy 7075-T6). ...

  9. MULTIAXIAL FATIGUE OF A RAILWAY WHEEL STEEL

    OpenAIRE

    CHIN-SUNG CHUNG; HO-KYUNG KIM

    2015-01-01

    Uniaxial and biaxial torsional fatigue specimens were extracted from a railway wheel steel. The fatigue tests were performed with the stress ratio of R= -1 by using uniaxial and biaxial torsional fatigue test specimens at room temperature in air. The ultimate and yield strengths of the steel were evaluated. The uniaxial fatigue limit was 422.5 MPa, which corresponds to 67% of the ultimate tensile strength. The ratio of e  e  / was 0.63. Appropriate parameters to predict the fatigue life ...

  10. Yaw control using rear wheel steering

    OpenAIRE

    Westbom, Daniel; Frejinger, Petter

    2002-01-01

    The purpose of this project is to continue the work on a vehicle model developed in ADAMS/Car and applied with the concept of ACM (Autonomous Corner Module). The project is divided up in two parts. The objective of the first part is to setup a co-simulation environment between ADAMS/Car and MATLAB/Simulink, and evaluate the vehicle model. In the second part a yaw controller is developed using only the rear wheel steering possibilities. The controller will be evaluated when it is applied on th...

  11. Innovative stair climber using associated wheels

    Science.gov (United States)

    Modak, Girish Sudhir; Bhoomkar, Manmohan Manikrao

    2016-03-01

    The study proposes an innovative and completely new but low-cost configuration of a platform that can easily climb stairs. This platform serves the purpose of a chassis. Different versions, such as staircase-climbing wheelchair or staircase-climbing trolley for material transferring, can be derived depending on the structure built on the platform. The driving wheels have a shape that completely matches with the profile of the steps. Complex components are eliminated. Thus, this platform is conveniently applicable in the configurations useful for climbing staircases.

  12. Big Data ethics

    NARCIS (Netherlands)

    Zwitter, Andrej

    2014-01-01

    The speed of development in Big Data and associated phenomena, such as social media, has surpassed the capacity of the average consumer to understand his or her actions and their knock-on effects. We are moving towards changes in how ethics has to be perceived: away from individual decisions with sp

  13. Space big book

    CERN Document Server

    Homer, Charlene

    2007-01-01

    Our Combined resource includes all necessary areas of Space for grades five to eight. Get the big picture about the Solar System, Galaxies and the Universe as your students become fascinated by the interesting information about the Sun, Earth, Moon, Comets, Asteroids Meteoroids, Stars and Constellations. Also, thrill your young astronomers as they connect Earth and space cycles with their daily life.

  14. The Big Bang

    CERN Multimedia

    Moods, Patrick

    2006-01-01

    How did the Universe begin? The favoured theory is that everything - space, time, matter - came into existence at the same moment, around 13.7 thousand million years ago. This event was scornfully referred to as the "Big Bang" by Sir Fred Hoyle, who did not believe in it and maintained that the Universe had always existed.

  15. A Big Bang Lab

    Science.gov (United States)

    Scheider, Walter

    2005-01-01

    The February 2005 issue of The Science Teacher (TST) reminded everyone that by learning how scientists study stars, students gain an understanding of how science measures things that can not be set up in lab, either because they are too big, too far away, or happened in a very distant past. The authors of "How Far are the Stars?" show how the…

  16. Governing Big Data

    Directory of Open Access Journals (Sweden)

    Andrej J. Zwitter

    2014-04-01

    Full Text Available 2.5 quintillion bytes of data are created every day through pictures, messages, gps-data, etc. "Big Data" is seen simultaneously as the new Philosophers Stone and Pandora's box: a source of great knowledge and power, but equally, the root of serious problems.

  17. The big bang

    Science.gov (United States)

    Silk, Joseph

    Our universe was born billions of years ago in a hot, violent explosion of elementary particles and radiation - the big bang. What do we know about this ultimate moment of creation, and how do we know it? Drawing upon the latest theories and technology, this new edition of The big bang, is a sweeping, lucid account of the event that set the universe in motion. Joseph Silk begins his story with the first microseconds of the big bang, on through the evolution of stars, galaxies, clusters of galaxies, quasars, and into the distant future of our universe. He also explores the fascinating evidence for the big bang model and recounts the history of cosmological speculation. Revised and updated, this new edition features all the most recent astronomical advances, including: Photos and measurements from the Hubble Space Telescope, Cosmic Background Explorer Satellite (COBE), and Infrared Space Observatory; the latest estimates of the age of the universe; new ideas in string and superstring theory; recent experiments on neutrino detection; new theories about the presence of dark matter in galaxies; new developments in the theory of the formation and evolution of galaxies; the latest ideas about black holes, worm holes, quantum foam, and multiple universes.

  18. Big Java late objects

    CERN Document Server

    Horstmann, Cay S

    2012-01-01

    Big Java: Late Objects is a comprehensive introduction to Java and computer programming, which focuses on the principles of programming, software engineering, and effective learning. It is designed for a two-semester first course in programming for computer science students.

  19. Big is beautiful

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, J.P.

    2007-06-08

    Although big solar systems are both effective and architecturally pleasing, they are still not widespread in Germany. Recently, politicians reacted by improving funding conditions. In order to prevent planning errors, planners and fitters must be better trained, and standardisation of systems must be enhanced. (orig.)

  20. Big ideas: innovation policy

    OpenAIRE

    Van Reenen, John

    2011-01-01

    In the last CentrePiece, John Van Reenen stressed the importance of competition and labour market flexibility for productivity growth. His latest in CEP's 'big ideas' series describes the impact of research on how policy-makers can influence innovation more directly - through tax credits for business spending on research and development.

  1. Business and Science - Big Data, Big Picture

    Science.gov (United States)

    Rosati, A.

    2013-12-01

    Data Science is more than the creation, manipulation, and transformation of data. It is more than Big Data. The business world seems to have a hold on the term 'data science' and, for now, they define what it means. But business is very different than science. In this talk, I address how large datasets, Big Data, and data science are conceptually different in business and science worlds. I focus on the types of questions each realm asks, the data needed, and the consequences of findings. Gone are the days of datasets being created or collected to serve only one purpose or project. The trick with data reuse is to become familiar enough with a dataset to be able to combine it with other data and extract accurate results. As a Data Curator for the Advanced Cooperative Arctic Data and Information Service (ACADIS), my specialty is communication. Our team enables Arctic sciences by ensuring datasets are well documented and can be understood by reusers. Previously, I served as a data community liaison for the North American Regional Climate Change Assessment Program (NARCCAP). Again, my specialty was communicating complex instructions and ideas to a broad audience of data users. Before entering the science world, I was an entrepreneur. I have a bachelor's degree in economics and a master's degree in environmental social science. I am currently pursuing a Ph.D. in Geography. Because my background has embraced both the business and science worlds, I would like to share my perspectives on data, data reuse, data documentation, and the presentation or communication of findings. My experiences show that each can inform and support the other.

  2. Big Data and Chemical Education

    Science.gov (United States)

    Pence, Harry E.; Williams, Antony J.

    2016-01-01

    The amount of computerized information that organizations collect and process is growing so large that the term Big Data is commonly being used to describe the situation. Accordingly, Big Data is defined by a combination of the Volume, Variety, Velocity, and Veracity of the data being processed. Big Data tools are already having an impact in…

  3. Simulation of Intelligent Single Wheel Mobile Robot

    Directory of Open Access Journals (Sweden)

    Maki K. Rashid

    2008-11-01

    Full Text Available Stabilization of a single wheel mobile robot attracted researcher attentions in robotic area. However, the budget requirements for building experimental setups capable in investigating isolated parameters and implementing others encouraged the development of new simulation methods and techniques that beat such limitations. In this work we have developed a simulation platform for testing different control tactics to stabilize a single wheel mobile robot. The graphic representation of the robot, the dynamic solution, and, the control scheme are all integrated on common computer platform using Visual Basic. Simulation indicates that we can control such robot without knowing the detail of it's internal structure or dynamics behaviour just by looking at it and using manual operation tactics. Twenty five rules are extracted and implemented using Takagi-Sugeno's fuzzy controller with significant achievement in controlling robot motion during the dynamic simulation. The resulted data from the successful implementation of the fuzzy model are used to utilize and train a neurofuzzy controller using ANFIS scheme to produce further improvement in robot performance

  4. New Small Wheel Technical Design Report

    CERN Document Server

    Kawamoto, T; Pontecorvo, L; Dubbert, J; Mikenberg, G; Iengo, P; Dallapiccola, C; Amelung, C; Levinson, L; Richter, R; Lellouch, D; CERN. Geneva. The LHC experiments Committee; LHCC

    2013-01-01

    In order to benefit from the expected high luminosity performance that will be provided by the Phase-I upgraded LHC, the first station of the ATLAS muon end-cap system (Small Wheel,SW) will need to be replaced. The New Small Wheel (NSW) will have to operate in a high background radiation region (up to 15 kHz=cm2) while reconstructing muon tracks with high precision, as well as furnishing information for the Level-1 trigger. These performance criteria are demanding. In particular, the precision reconstruction of tracks for offline analysis requires a spatial resolution of about 100microns, and the Level-1 trigger track segments have to be reconstructed online with an angular resolution of approximately 1mrad. The NSW will have two chamber technologies, one primarily devoted to the Level-1 trigger function (small-strip Thin Gap Chambers, sTGC) and one dedicated to precision tracking (Micromegas detectors, MM). The sTGC are primarily deployed for triggering given their single bunch crossing identification capabi...

  5. Fatigue Properties of Cast Magnesium Wheels

    Science.gov (United States)

    Li, Zhenming; Luo, Alan A.; Wang, Qigui; Peng, Liming; Zhang, Peng

    2016-05-01

    This paper investigates the fatigue properties and deformation behavior of a newly developed Mg-2.96Nd-0.21Zn-0.39Zr magnesium alloy wheel in both as-cast and T6 conditions. Compared with the as-cast alloy, the T6-treated alloy shows a significant increase in fatigue strength and cyclic stress amplitude. This is believed to be attributed to the change of defect type from porosity to oxides and the increased matrix strength in the T6 (peak-aged) condition. For the as-cast alloy wheel, fatigue failure mainly originated from the cast defects including porosity, oxide film, and inclusion at or near the sample surface. In the T6-treated alloy, however, oxides and inclusions or slip bands initiate the fatigue cracks. Solution treatment appears to reduce or eliminate the shrinkage porosity because of grain growth and dissolution of as-cast eutectic phases in the grain boundaries. The cyclic stress amplitude of the as-cast alloy increases with increasing the number of cycles, while the T6-treated alloy shows cyclic softening after the stress reaches a maximum value. The Coffin-Manson law and Basquin equation can be used to evaluate the life of low cycle fatigue. The developed long crack model and multi-scale fatigue (MSF) models can be used to predict high-cycle fatigue life of the Mg-2.96Nd-0.21Zn-0.39Zr alloys with or without casting defects.

  6. Identifying Dwarfs Workloads in Big Data Analytics

    OpenAIRE

    Gao, Wanling; Luo, Chunjie; Zhan, Jianfeng; Ye, Hainan; He, Xiwen; Wang, Lei; Zhu, Yuqing; Tian, Xinhui

    2015-01-01

    Big data benchmarking is particularly important and provides applicable yardsticks for evaluating booming big data systems. However, wide coverage and great complexity of big data computing impose big challenges on big data benchmarking. How can we construct a benchmark suite using a minimum set of units of computation to represent diversity of big data analytics workloads? Big data dwarfs are abstractions of extracting frequently appearing operations in big data computing. One dwarf represen...

  7. Automatic detection of flats on the rolling stock wheels

    Directory of Open Access Journals (Sweden)

    J. Madejski

    2006-04-01

    Full Text Available Purpose: The goal of this work was increasing safety of tram, metro and trams operation.Design/methodology/approach: The accelerometers were fixed directly to the rail to provide the system with the best defect signal quality. Analysis of the acoustic signals collected using microphones proved that too much of the background noise limited their usefulness.Findings: It has been proven that all wheel geometry defects can be reliably detected and classified according to the experimentally established defect categories.Research limitations/implications: Exact measurements of the wheel defect geometry may be possible only after collecting huge signals time series along with the wheel measurements taken with other methods to reveal the relationships between them. This goal is hard to achieve, as the system performs already very well, and such experiments would be very costly and time consuming.Practical implications: Integrated wheel geometrical data collected from the wheel ovality, flat spots, and build-up detection system along with the wheel profile information have eliminated all derailments due to faulty wheel geometry.Originality/value: The system presented is the first wheel monitoring application in Poland, its unique feature is that it can be used at low speeds, like those allowed in depots.

  8. Wheeling and transmission system service policy in North America

    International Nuclear Information System (INIS)

    This paper provides a review and discussion of the status of wheeling in the USA and Canada; the pros and cons of the new policies that are evolving and under consideration for wheeling and transmission access; specific case examples of some of the difficulties that have arisen; and the potential for new transmission technology. (author)

  9. 14 CFR 25.497 - Tail-wheel yawing.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Tail-wheel yawing. 25.497 Section 25.497 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure Ground Loads § 25.497 Tail-wheel yawing. (a) A...

  10. First Wheel of the Hadronic EndCap Calorimeter Completed

    CERN Multimedia

    Oram, C.J.

    2002-01-01

    With the LAr calorimeters well advanced in module production, the attention is turning to Batiment 180 where the calorimeter modules are formed into complete detectors and inserted into their respective cryostats. For the Hadronic End Cap (HEC) Group the task in B180 is to assemble the wheels, rotate them into their final orientation, and put them onto the cradle in front of the End Cap Cryostat. These tasks have been completed for the first HEC wheel in the B180 End Cap Clean Room. Given that this wheel weighs 70 tons the group is very relieved to have established that these gymnastics with the wheel proceed in a routine fashion. To assemble a wheel we take modules that have already been cold tested, do the final electrical testing and locate them onto the HEC wheel assembly table. Four wheels are required in total, each consisting of 32 modules. Wheel assembly is done in the horizontal position, creating a doughnut-like object sitting on the HEC table. The first picture shows the last module being added ...

  11. Hybrid Control Design for a Wheeled Mobile Robot

    DEFF Research Database (Denmark)

    Bak, Thomas; Bendtsen, Jan Dimon; Ravn, Anders Peter

    We present a hybrid systems solution to the problem of trajectory tracking for a four-wheel steered four-wheel driven mobile robot. The robot is modelled as a non-holonomic dynamic system subject to pure rolling, no-slip constraints. Under normal driving conditions, a nonlinear trajectory tracking...

  12. Hybrid Control Design for a Wheeled Mobile Robot

    DEFF Research Database (Denmark)

    Bak, Thomas; Bendtsen, Jan Dimon; Ravn, Anders Peter

    2003-01-01

    We present a hybrid systems solution to the problem of trajectory tracking for a four-wheel steered four-wheel driven mobile robot. The robot is modelled as a non-holonomic dynamic system subject to pure rolling, no-slip constraints. Under normal driving conditions, a nonlinear trajectory tracking...

  13. The Wheels of Stress Go 'Round and 'Round

    Science.gov (United States)

    Brey, Rebecca A.; Clark, Susan E.

    2012-01-01

    "The Wheels of Stress Go Round and Round" teaching idea uses three activity wheels to reinforce stress-related content and concepts. After presenting a definition of stress, the instructor assists students in identifying stressors, and aids in formulating a list of negative, reactive behaviors and a list of positive coping mechanisms. Using…

  14. Considering the Influence of Prerequisite Performance on Wheel Spinning

    Science.gov (United States)

    Wan, Hao; Beck, Joseph Barbosa

    2015-01-01

    The phenomenon of wheel spinning refers to students attempting to solve problems on a particular skill, but becoming stuck due to an inability to learn the skill. Past research has found that students who do not master a skill quickly tend not to master it at all. One question is why do students wheel spin? A plausible hypothesis is that students…

  15. Hybrid Control Design for a Wheeled Mobile Robot

    DEFF Research Database (Denmark)

    Bak, Thomas; Bendtsen, Jan Dimon; Ravn, Anders Peter

    2003-01-01

    We present a hybrid systems solution to the problem of trajectory tracking for a four-wheel steered four-wheel driven mobile robot. The robot is modelled as a non-holonomic dynamic system subject to pure rolling, no-slip constraints. Under normal driving conditions, a nonlinear trajectory trackin...

  16. Controlling omni-directional Wheels of a MSL RoboCup autonomous mobile robot

    OpenAIRE

    Ribeiro, António Fernando; Moutinho, Ivo; Silva, Pedro; Fraga, Carlos; Pereira, Nino

    2004-01-01

    Autonomous Mobile Locomotion is of extreme importance in RoboCup robots. Even though in 2050 the robotic team will very likely use legs rather than wheels, at the moment all teams on middle size league use wheels to overcome other problems first. Most teams are using two driving wheels (with one or two cast wheels), four driving wheels and even three driving wheels. The Minho team has been using two driving wheels for the last 5 years (with two caster wheels), but for reaction speed optimi...

  17. Nonlinear analysis of the GFRP material wheel hub

    Directory of Open Access Journals (Sweden)

    Dong Yun-Feng

    2015-01-01

    Full Text Available In this paper, the current bicycle wheel was replaced by the ones which composed by the wheel hub with Glassfiber Reinforced Plastic (alkali free thin-walled cylinder material, hereinafter referred to as GFRP material and the protective components made up of rubber outer pneumatic pad. With the help of the basic theory of elastic-plastic mechanics, the finite element “Nonlinear buckling” analysis of the wheel was carried out. The results show that the maximum elastic deformation of the wheel hub and the critical value of buckling failure load were restricted by the elasticity under the condition of external loads. Considering with the tensile strength and elastic modulus of the GFRP value of the material, it is demonstrated that the material is feasible to be used for wheel hub.

  18. A fully omnidirectional wheeled assembly for robotic vehicles

    International Nuclear Information System (INIS)

    A large number of wheeled or tracked platform mechanisms have been studied and developed to provide their mobility capability to teleoperated and autonomous robot vehicles. This paper presents an original wheeled platform based on an orthogonal wheel assembly that provides a full (three-degrees-of-freedom) omnidirectionality of the platform without wheel slippage and with the capability for simultaneous motions in rotation and translation (including sideways movements). A schematic of the basic wheel assembly is shown. The motion of the assembly is unconstrained (freewheeling) in the direction parallel to the main assembly shaft, while it is constrained in the direction perpendicular to the shaft, being driven in this direction by rotation of the shaft. A prototype platform was constructed to demonstrate the feasibility of this new concept

  19. ANALYTICS OF BIG DATA

    Directory of Open Access Journals (Sweden)

    Asst. Prof. Shubhada Talegaon

    2014-10-01

    Full Text Available Big Data analytics has started to impact all types of organizations, as it carries the potential power to extract embedded knowledge from big amounts of data and react according to it in real time. The current technology enables us to efficiently store and query large datasets, the focus is now on techniques that make use of the complete data set, instead of sampling. This has tremendous implications in areas like machine learning, pattern recognition and classification, sentiment analysis, social networking analysis to name a few. Therefore, there are a number of requirements for moving beyond standard data mining technique. Purpose of this paper is to understand various techniques to analysis data.

  20. ANALYTICS OF BIG DATA

    Directory of Open Access Journals (Sweden)

    Prof. Shubhada Talegaon

    2015-10-01

    Full Text Available Big Data analytics has started to impact all types of organizations, as it carries the potential power to extract embedded knowledge from big amounts of data and react according to it in real time. The current technology enables us to efficiently store and query large datasets, the focus is now on techniques that make use of the complete data set, instead of sampling. This has tremendous implications in areas like machine learning, pattern recognition and classification, sentiment analysis, social networking analysis to name a few. Therefore, there are a number of requirements for moving beyond standard data mining technique. Purpose of this paper is to understand various techniques to analysis data.

  1. Big Data as Governmentality

    DEFF Research Database (Denmark)

    Flyverbom, Mikkel; Madsen, Anders Koed; Rasche, Andreas

    data is constituted as an aspiration to improve the data and knowledge underpinning development efforts. Based on this framework, we argue that big data’s impact on how relevant problems are governed is enabled by (1) new techniques of visualizing development issues, (2) linking aspects......This paper conceptualizes how large-scale data and algorithms condition and reshape knowledge production when addressing international development challenges. The concept of governmentality and four dimensions of an analytics of government are proposed as a theoretical framework to examine how big...... of the international development agenda to algorithms that synthesize large-scale data, (3) novel ways of rationalizing knowledge claims that underlie development policies, and (4) shifts in professional and organizational identities of those concerned with producing and processing data for development. Our discussion...

  2. Big Data as Governmentality

    DEFF Research Database (Denmark)

    Flyverbom, Mikkel; Klinkby Madsen, Anders; Rasche, Andreas

    data is constituted as an aspiration to improve the data and knowledge underpinning development efforts. Based on this framework, we argue that big data’s impact on how relevant problems are governed is enabled by (1) new techniques of visualizing development issues, (2) linking aspects......This paper conceptualizes how large-scale data and algorithms condition and reshape knowledge production when addressing international development challenges. The concept of governmentality and four dimensions of an analytics of government are proposed as a theoretical framework to examine how big...... of international development agendas to algorithms that synthesize large-scale data, (3) novel ways of rationalizing knowledge claims that underlie development efforts, and (4) shifts in professional and organizational identities of those concerned with producing and processing data for development. Our discussion...

  3. Really big numbers

    CERN Document Server

    Schwartz, Richard Evan

    2014-01-01

    In the American Mathematical Society's first-ever book for kids (and kids at heart), mathematician and author Richard Evan Schwartz leads math lovers of all ages on an innovative and strikingly illustrated journey through the infinite number system. By means of engaging, imaginative visuals and endearing narration, Schwartz manages the monumental task of presenting the complex concept of Big Numbers in fresh and relatable ways. The book begins with small, easily observable numbers before building up to truly gigantic ones, like a nonillion, a tredecillion, a googol, and even ones too huge for names! Any person, regardless of age, can benefit from reading this book. Readers will find themselves returning to its pages for a very long time, perpetually learning from and growing with the narrative as their knowledge deepens. Really Big Numbers is a wonderful enrichment for any math education program and is enthusiastically recommended to every teacher, parent and grandparent, student, child, or other individual i...

  4. Big Data Refinement

    OpenAIRE

    Boiten, Eerke Albert

    2016-01-01

    "Big data" has become a major area of research and associated funding, as well as a focus of utopian thinking. In the still growing research community, one of the favourite optimistic analogies for data processing is that of the oil refinery, extracting the essence out of the raw data. Pessimists look for their imagery to the other end of the petrol cycle, and talk about the "data exhausts" of our society. Obviously, the refinement community knows how to do "refining". This paper explores...

  5. DARPA's Big Mechanism program

    Science.gov (United States)

    Cohen, Paul R.

    2015-07-01

    Reductionist science produces causal models of small fragments of complicated systems. Causal models of entire systems can be hard to construct because what is known of them is distributed across a vast amount of literature. The Big Mechanism program aims to have machines read the literature and assemble the causal fragments found in individual papers into huge causal models, automatically. The current domain of the program is cell signalling associated with Ras-driven cancers.

  6. Canonical Big Operators

    OpenAIRE

    Bertot, Yves; Gonthier, Georges; Ould Biha, Sidi; Pasca, Ioana

    2008-01-01

    In this paper, we present an approach to describe uniformly iterated “big” operations and to provide lemmas that encapsulate all the commonly used reasoning steps on these constructs. We show that these iterated operations can be handled generically using the syntactic notation and canonical structure facilities provided by the Coq system. We then show how these canonical big operations played a crucial enabling role in the study of various parts of linear algebra and multi-dimensional real a...

  7. Big Bang 6

    CERN Document Server

    Apolin, Martin

    2008-01-01

    Physik soll verständlich sein und Spaß machen! Deshalb beginnt jedes Kapitel in Big Bang mit einem motivierenden Überblick und Fragestellungen und geht dann von den Grundlagen zu den Anwendungen, vom Einfachen zum Komplizierten. Dabei bleibt die Sprache einfach, alltagsorientiert und belletristisch. Der Band 6 RG behandelt die Gravitation, Schwingungen und Wellen, Thermodynamik und eine Einführung in die Elektrizität anhand von Alltagsbeispielen und Querverbindungen zu anderen Disziplinen.

  8. Big Bang 7

    CERN Document Server

    Apolin, Martin

    2008-01-01

    Physik soll verständlich sein und Spaß machen! Deshalb beginnt jedes Kapitel in Big Bang mit einem motivierenden Überblick und Fragestellungen und geht dann von den Grundlagen zu den Anwendungen, vom Einfachen zum Komplizierten. Dabei bleibt die Sprache einfach, alltagsorientiert und belletristisch. In Band 7 werden neben einer Einführung auch viele aktuelle Aspekte von Quantenmechanik (z. Beamen) und Elektrodynamik (zB Elektrosmog), sowie die Klimaproblematik und die Chaostheorie behandelt.

  9. Big Bang 8

    CERN Document Server

    Apolin, Martin

    2008-01-01

    Physik soll verständlich sein und Spaß machen! Deshalb beginnt jedes Kapitel in Big Bang mit einem motivierenden Überblick und Fragestellungen und geht dann von den Grundlagen zu den Anwendungen, vom Einfachen zum Komplizierten. Dabei bleibt die Sprache einfach, alltagsorientiert und belletristisch. Band 8 vermittelt auf verständliche Weise Relativitätstheorie, Kern- und Teilchenphysik (und deren Anwendungen in der Kosmologie und Astrophysik), Nanotechnologie sowie Bionik.

  10. Big Bang 5

    CERN Document Server

    Apolin, Martin

    2007-01-01

    Physik soll verständlich sein und Spaß machen! Deshalb beginnt jedes Kapitel in Big Bang mit einem motivierenden Überblick und Fragestellungen und geht dann von den Grundlagen zu den Anwendungen, vom Einfachen zum Komplizierten. Dabei bleibt die Sprache einfach, alltagsorientiert und belletristisch. Der Band 5 RG behandelt die Grundlagen (Maßsystem, Größenordnungen) und die Mechanik (Translation, Rotation, Kraft, Erhaltungssätze).

  11. Think Small Go Big

    Institute of Scientific and Technical Information of China (English)

    汤维维

    2006-01-01

    Vepoo公司在创立之前,经历了三次创业转型。用他们的话来说,从“think big go small”转到“think small go big”用了一年的时间。这期间他们耗尽了初期筹备资金,幸运的是在最后一刻迎来了黎明的曙光。

  12. Infinity properads and infinity wheeled properads

    CERN Document Server

    Hackney, Philip; Yau, Donald

    2015-01-01

    The topic of this book sits at the interface of the theory of higher categories (in the guise of (∞,1)-categories) and the theory of properads. Properads are devices more general than operads, and enable one to encode bialgebraic, rather than just (co)algebraic, structures.   The text extends both the Joyal-Lurie approach to higher categories and the Cisinski-Moerdijk-Weiss approach to higher operads, and provides a foundation for a broad study of the homotopy theory of properads. This work also serves as a complete guide to the generalised graphs which are pervasive in the study of operads and properads. A preliminary list of potential applications and extensions comprises the final chapter.   Infinity Properads and Infinity Wheeled Properads is written for mathematicians in the fields of topology, algebra, category theory, and related areas. It is written roughly at the second year graduate level, and assumes a basic knowledge of category theory.

  13. Well-to-wheel energy analysis study

    International Nuclear Information System (INIS)

    The analysis evaluates separately the fuel cycle (well to tank) and the propulsion (and emission control) systems (tank to wheel). The analysis assessed 75 different fuel pathways (gasoline diesel, Fischer Tropsch diesel, ethanol, methanol, hydrogen, and natural gas) and 15 different propulsion systems (conventional, conventional hybrid, and fuel cell) on a single vehicle type (GM full-size pickup). The results show that in terms of primary energy consumption, petroleum hybrid engines or fuel cell engines are significantly better than most natural gas options and all renewable options. However, in terms of greenhouse gas emissions, fuel-cell vehicles offer a clear edge (although diesel-engine hybrid vehicles are close), but renewable fuel options using ethanol (from biomass fermentation) offer the lowest emissions. (author)

  14. The sensory wheel of virgin olive oil

    Directory of Open Access Journals (Sweden)

    Mojet, Jos

    1994-04-01

    Full Text Available During a 3-year FLAIR study extra virgin olive oils, varying in species, degree of ripeness and extraction method, were evaluated by 6 different institutes according to QDA or GDI-methods in order to identify parameters related to the quality of extra virgin olive oil. The current COI-method yields a poor between-panel reproducibility. This could well be caused by a difference in the perception of positive quality aspects. Whereas the QDA-method is especially suitable for determining sensory profiles according to the perception of the consumer, the COI-method should be tailored to detect possible defects only.
    In order to cluster all attributes to one condensed set of sensory attributes for describing virgin olive oil, the COI and QDA data of ail panels were pooled and analyzed separately for appearance, texture and flavour. This approach resulted in a set of 3 appearance, 3 texture and 12 flavour descriptors which can be conveniently represented graphically in the form of a "sensory wheel".
    On the basis of the findings it is recommended to base the "extra virgin" qualification for olive oils solely on the absence of defects. The between-panel reproducibility of such a simplified COI-test can be assessed by means of ring tests and improved by training with reference products. When an oil passes this screening it can be profiled subsequently using the attributes of the sensory wheel. Such a profile can be linked to preferential profiles derived from consumer studies enabling the production of most preferred olive oils.

  15. Online measurement for geometrical parameters of locomotive wheel set

    Science.gov (United States)

    Wu, Kaihua; Li, Zhengjie; Ban, Tao

    2009-11-01

    Locomotive is the most important parts of a train. Wheel set is the major running components of a locomotive. Wheel set tread is the contacting part with the rail and tread will be worn down gradually. The wearing degree of the wheel set tread is one of the main factors that influence the safety and stability of running train. The measurement of wheel set wear is usually static and by handwork, which limits the accuracy and reliability. An automatic measurement method for geometrical parameters of locomotive wheel set based on optoelectronic technique was proposed. Geometrical parameters include flange thickness, flange height and rim inside distance. Linear structured laser light was projected on the wheel tread surface. The geometrical parameters can be deduced from the profile image. An online image acquisition system was designed based on asynchronous reset of CCD. Precision hardware time-delay and asynchronous reset pulse generation circuits were designed. The entire time sequence of asynchronous reset was researched. Images were acquired only when wheel sets moved into the designed position. The image acquisition was fulfilled by hardware interrupt mode. The measuring system was installed along the straight railway section. When the locomotive was running in a limited speed, the devices placed alone railway line can measure the geometrical parameters automatically.

  16. Model-based analysis and simulation of regenerative heat wheel

    DEFF Research Database (Denmark)

    Wu, Zhuang; Melnik, Roderick V. N.; Borup, F.

    2006-01-01

    The rotary regenerator (also called the heat wheel) is an important component of energy intensive sectors, which is used in many heat recovery systems. In this paper, a model-based analysis of a rotary regenerator is carried out with a major emphasis given to the development and implementation of...... mathematical models for the thermal analysis of the fluid and wheel matrix. The effect of heat conduction in the direction of the fluid flow is taken into account and the influence of variations in rotating speed of the wheel as well as other characteristics (ambient temperature, airflow and geometric size) on...

  17. Symbolic derivation of bicycle kinematics with toroidal wheels

    Directory of Open Access Journals (Sweden)

    Wang Everett X.

    2015-01-01

    Full Text Available Bicycle kinematics with toroidal wheels is presented in this paper. Using symbolic mathematic tool Maple, we obtain two holonomic and four nonholonomic constraint equations due to front and rear wheels of a bicycle. We show that the two holonomic constraints cannot be expressed in quartic form for bicycle rear body pitch angle unless the minor (crown radius of the torus are the same for both the front and rear wheels. In addition, we show that all the constraints can be written in differential form, from which a constraint matrix is constructed, according to standard procedure for developing dynamics in robotics.

  18. Impulsive dynamics and stabilization of a single wheel robot

    Institute of Scientific and Technical Information of China (English)

    Ou Yongsheng; Wu Xinyu; Xu Yangsheng

    2011-01-01

    The impulsive motion of a dynamically stabilized robot-Gyrover, which is a single-wheel gyroscopically stabilized robot is studied. A method based on the D' Alembert-Lagrange principle is proposed to develop the impulsive dynamic model of the single wheel robot. This method that can be used to find ways to investigate a single wheel mobile robot rolling on a rough terrain is tested using the experimental platform Gyrover. The conditions of falling over without actuators are addressed. Simulations that validate the analysis are provided as well.

  19. Identification of wheeling paths by an extended sensitivity analysis

    International Nuclear Information System (INIS)

    This paper proposes a practical method for identifying wheeling paths in deregulated electricity markets based on an extended sensitivity analysis. Using this method, it becomes possible to decide the proper and fair wheeling rate according to the degree of burden on transmission lines by each power flow transaction. Moreover, a wheeling rate based on the real power flow burden is also an important signal to new power suppliers in the markets. In order to show the validity of the proposed method, a series of simulations on the IEEE 30-bus test system were conducted. (author)

  20. From Big Bang to Big Crunch and Beyond

    OpenAIRE

    Elitzur, S.; Giveon, A.; Kutasov, D.; Rabinovici, E.

    2002-01-01

    We study a quotient Conformal Field Theory, which describes a 3+1 dimensional cosmological spacetime. Part of this spacetime is the Nappi-Witten (NW) universe, which starts at a ``big bang'' singularity, expands and then contracts to a ``big crunch'' singularity at a finite time. The gauged WZW model contains a number of copies of the NW spacetime, with each copy connected to the preceeding one and to the next one at the respective big bang/big crunch singularities. The sequence of NW spaceti...

  1. How Big is Earth?

    Science.gov (United States)

    Thurber, Bonnie B.

    2015-08-01

    How Big is Earth celebrates the Year of Light. Using only the sunlight striking the Earth and a wooden dowel, students meet each other and then measure the circumference of the earth. Eratosthenes did it over 2,000 years ago. In Cosmos, Carl Sagan shared the process by which Eratosthenes measured the angle of the shadow cast at local noon when sunlight strikes a stick positioned perpendicular to the ground. By comparing his measurement to another made a distance away, Eratosthenes was able to calculate the circumference of the earth. How Big is Earth provides an online learning environment where students do science the same way Eratosthenes did. A notable project in which this was done was The Eratosthenes Project, conducted in 2005 as part of the World Year of Physics; in fact, we will be drawing on the teacher's guide developed by that project.How Big Is Earth? expands on the Eratosthenes project by providing an online learning environment provided by the iCollaboratory, www.icollaboratory.org, where teachers and students from Sweden, China, Nepal, Russia, Morocco, and the United States collaborate, share data, and reflect on their learning of science and astronomy. They are sharing their information and discussing their ideas/brainstorming the solutions in a discussion forum. There is an ongoing database of student measurements and another database to collect data on both teacher and student learning from surveys, discussions, and self-reflection done online.We will share our research about the kinds of learning that takes place only in global collaborations.The entrance address for the iCollaboratory is http://www.icollaboratory.org.

  2. REDUCING THE NEGATIVE INFLUENCE OF KINEMATIC DISCREPANCY IN THE TRANSMISSION OF FOUR-WHEEL DRIVE WHEELED VEHICLES

    OpenAIRE

    Ismailov V. A.; Melikov I. M.

    2015-01-01

    The article discusses different types of drive axles of all-wheel drive machine. It is shown that if blocked drive of driving axle easy, it is able to provide the best traction drive qualities of the all-wheel car, if compensation of kinematic mismatch in movement of front and rear wheels. The article provides analysis of the causes of kinematic mismatch and its consequences. The analysis was given for the existing methods to reduce negative influence of kinematic discrepancy on the work of t...

  3. Big Bang Nucleosynthesis Calculation

    CERN Document Server

    Kurki-Suonio, H

    2001-01-01

    I review standard big bang nucleosynthesis and some versions of nonstandard BBN. The abundances of the primordial isotopes D, He-3, and Li-7 produced in standard BBN can be calculated as a function of the baryon density with an accuracy of about 10%. For He-4 the accuracy is better than 1%. The calculated abundances agree fairly well with observations, but the baryon density of the universe cannot be determined with high precision. Possibilities for nonstandard BBN include inhomogeneous and antimatter BBN and nonzero neutrino chemical potentials.

  4. A Matrix Big Bang

    OpenAIRE

    Craps, Ben; Sethi, Savdeep; Verlinde, Erik

    2005-01-01

    The light-like linear dilaton background represents a particularly simple time-dependent 1/2 BPS solution of critical type IIA superstring theory in ten dimensions. Its lift to M-theory, as well as its Einstein frame metric, are singular in the sense that the geometry is geodesically incomplete and the Riemann tensor diverges along a light-like subspace of codimension one. We study this background as a model for a big bang type singularity in string theory/M-theory. We construct the dual Matr...

  5. Big and little OER

    OpenAIRE

    Weller, Martin

    2010-01-01

    Much of the attention around OERs has been on institutional projects which make explicit learning content available. These can be classified as ‘big OER’, but another form of OER is that of small scale, individually produced resources using web 2.0 type services, which are classified as ‘little OER’. This paper examines some of the differences between the use of these two types of OER to highlight issues in open education. These include attitudes towards reputation, the intentionality of the ...

  6. Big Red Telephone, Gone

    Institute of Scientific and Technical Information of China (English)

    Toni Piech

    2006-01-01

    @@ The Chinese big red telephones looked exactly as Iimagined the ones servicing the direct emergen line between the Kreml and the White House duing the cold-war era would have look like. But here in China, every kio seemed to have such a device in t1990s, and anyone could use it for ju 0.2 yuan. The government did not juinstall public phones on street corner but they let small-business owners pa ticipate in telecommunication. Supply and demand were juggled by a kind of Hutong capitalism.

  7. Big Data Challenges

    Directory of Open Access Journals (Sweden)

    Alexandru Adrian TOLE

    2013-10-01

    Full Text Available The amount of data that is traveling across the internet today, not only that is large, but is complex as well. Companies, institutions, healthcare system etc., all of them use piles of data which are further used for creating reports in order to ensure continuity regarding the services that they have to offer. The process behind the results that these entities requests represents a challenge for software developers and companies that provide IT infrastructure. The challenge is how to manipulate an impressive volume of data that has to be securely delivered through the internet and reach its destination intact. This paper treats the challenges that Big Data creates.

  8. Privacy and Big Data

    CERN Document Server

    Craig, Terence

    2011-01-01

    Much of what constitutes Big Data is information about us. Through our online activities, we leave an easy-to-follow trail of digital footprints that reveal who we are, what we buy, where we go, and much more. This eye-opening book explores the raging privacy debate over the use of personal data, with one undeniable conclusion: once data's been collected, we have absolutely no control over who uses it or how it is used. Personal data is the hottest commodity on the market today-truly more valuable than gold. We are the asset that every company, industry, non-profit, and government wants. Pri

  9. Bigness in compatible systems

    OpenAIRE

    Snowden, Andrew; Wiles, Andrew

    2009-01-01

    Clozel, Harris and Taylor have recently proved a modularity lifting theorem of the following general form: if rho is an l-adic representation of the absolute Galois group of a number field for which the residual representation rho-bar comes from a modular form then so does rho. This theorem has numerous hypotheses; a crucial one is that the image of rho-bar must be "big," a technical condition on subgroups of GL(n). In this paper we investigate this condition in compatible systems. Our main r...

  10. Obstacle performance of cobalt-enriching crust wheeled mining vehicle

    Institute of Scientific and Technical Information of China (English)

    HUANG Zhong-hua; LIU Shao-jun; XIE Ya

    2006-01-01

    A cobalt-enriching crust mining vehicle with four independent driven wheels was proposed. The influence of center-of-gravity position of mining vehicle on obstacle performance was studied. The results show that the mining vehicle has optimal obstacle performance with center-of-gravity position in the middle of suspension. A virtual prototype based on ADAMS software was built and its obstacle performance was simulated. Simulation results show that the mining vehicle with four independent driven wheels has excellent obstacle performance, the maximum climbing capacity is no less than 30°, the maximal ditch width and shoulder height are no less than wheel radius ofmining vehicle. Thus wheeled mining vehicle is feasible for cobalt-enriching crust commercial mining.

  11. Vehicle wheels vibration suppression by dynamic vibration absorber

    Directory of Open Access Journals (Sweden)

    Zinovij STOTSKO

    2007-01-01

    Full Text Available The article deals with the methods of calculation and optimization ofdynamic processes in vibroexcitated constructions with dynamic absorbers. The improved constructions of such absorbers for vehicle wheels vibration suppression are discussed.

  12. Forces on wheels and fuel consumption in cars

    CERN Document Server

    Güémez, J

    2014-01-01

    Motivated by real classroom discussions, we analyse the forces acting on moving vehicles, specifically friction forces on the wheels. In usual cars, with front-wheel drive, when the car accelerates these forces are in the forward direction in the front wheels, but they are in the opposite direction in the rear wheels. The situation may be intriguing for students, but it may also be helpful and stimulating to clarify the role of friction forces on rolling objects. In this article we also study thermodynamical aspects of an accelerating car, relating the distance traveled with the amount of fuel consumed. The fuel consumption is explicitly shown to be Galilean invariant and we identify the Gibbs free energy as the relevant quantity that enters in the thermodynamical description of the accelerating car. The more realistic case of the car's motion taking into account the dragging forces is also discussed.

  13. Fluid Mechanics of a High Performance Racing Bicycle Wheel

    Science.gov (United States)

    Mercat, Jean-Pierre; Cretoux, Brieuc; Huat, Francois-Xavier; Nordey, Benoit; Renaud, Maxime; Noca, Flavio

    2013-11-01

    In 2012, MAVIC released the most aerodynamic bicycle wheel on the market, the CXR 80. The french company MAVIC has been a world leader for many decades in the manufacturing of bicycle wheels for competitive events such as the Olympic Games and the Tour de France. Since 2010, MAVIC has been in a research partnership with the University of Applied Sciences in Geneva, Switzerland, for the aerodynamic development of bicycle wheels. While most of the development up to date has been performed in a classical wind tunnel, recent work has been conducted in an unusual setting, a hydrodynamic towing tank, in order to achieve low levels of turbulence and facilitate quantitative flow visualization (PIV). After a short introduction on the aerodynamics of bicycle wheels, preliminary fluid mechanics results based on this novel setup will be presented.

  14. Miniature Reaction Wheel for Small Satellite Control Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The overall goal of this project is to design, develop, demonstrate, and deliver a miniature, high torque, low-vibration reaction wheel for use on small satellites....

  15. Numerical and experimental analysis of a solid desiccant wheel

    Directory of Open Access Journals (Sweden)

    Koronaki Irene P.

    2016-01-01

    Full Text Available The rotary desiccant dehumidifier is an important component which can be used in air conditioning systems in order to reduce the electrical energy consumption and introduce renewable energy sources. In this study a one dimensional gas side resistance model is presented for predicting the performance of the desiccant wheel. Measurements from two real sorption wheels are used in order to validate the model. One wheel uses silica gel as desiccant material and the other lithium chloride. The simulation results are in good agreement with the experimental data. The model is used to compare the counter flow with the co-current wheel arrangements and to explain why the counter flow one is more efficient for air dehumidification.

  16. BICARBONATE OF SODA BLASTING TECHNOLOGY FOR AIRCRAFT WHEEL DEPAINTING

    Science.gov (United States)

    This evaluation addressed product quality, waste reduction/pollution prevention and economics in replacing chemical solvent strippers with a bicarbonate of soda blasting technology for removal of point from aircraft wheels. he evaluation was conducted in the Paint Stripping Shop ...

  17. BICARBONATE OF SODA BLASTING TECHNOLOGY FOR AIRCRAFT WHEEL PAINTING

    Science.gov (United States)

    This evaluation addressed product quality, waste reduction/pollution prevention and economics in replacing chemical solvent strippers with a bicarbonate of soda blasting technology for removal of paint from aircraft wheels. The evaluation was conducted in the Paint Stripping Sho...

  18. Forces on wheels and fuel consumption in cars

    International Nuclear Information System (INIS)

    Motivated by real classroom discussions, we analyze the forces acting on moving vehicles, specifically friction on their wheels. In typical front-wheel-drive cars when the car accelerates these forces are in the forward direction in the front wheels, but they are in the opposite direction in the rear wheels. The situation may be intriguing for students, but it may also be helpful and stimulating to clarify the role of friction forces on rolling objects. In this paper we also study the thermodynamical aspects of an accelerating car, relating the distance traveled to the amount of fuel consumed. The fuel consumption is explicitly shown to be Galilean invariant and we identify the Gibbs free energy as the relevant quantity that enters into the thermodynamical description of the accelerating car. The more realistic case of the car's motion with the dragging forces taken into account is also discussed. (paper)

  19. Characterization of grinding wheels: An annotated Bibliography. Final report

    Energy Technology Data Exchange (ETDEWEB)

    McClung, R.W.

    1995-12-01

    The characteristics of grinding wheels, after both fabrication and periods of operation, have a significant effect on the processed surface and the mechanical properties of advanced ceramics. An extensive literature survey and review has been conducted to determine and catalogue the various characterization methods that have been investigated and reported. Although many of the references have addressed the grinding of metals, the historical and technical merit justify their inclusion in this bibliography. For convenience, the references have been subdivided into nine subheadings: Nondestructive examination; elasticity and stiffness; wheel hardness; topography and profilometry; observation of texture of wheel surfaces wheel wear; in process monitoring of grinding, acoustic emission, other; characteristics of ground surfaces; and miscellaneous.

  20. ILC TARGET WHEEL RIM FRAGMENT/GUARD PLATE IMPACT ANALYSIS

    Energy Technology Data Exchange (ETDEWEB)

    Hagler, L

    2008-07-17

    A positron source component is needed for the International Linear Collider Project. The leading design concept for this source is a rotating titanium alloy wheel whose spokes rotate through an intense localized magnetic field. The system is composed of an electric motor, flexible motor/drive-shaft coupling, stainless steel drive-shaft, two Plumber's Block tapered roller bearings, a titanium alloy target wheel, and electromagnet. Surrounding the target wheel and magnet is a steel frame with steel guarding plates intended to contain shrapnel in case of catastrophic wheel failure. Figure 1 is a layout of this system (guard plates not shown for clarity). This report documents the FEA analyses that were performed at LLNL to help determine, on a preliminary basis, the required guard plate thickness for three potential plate steels.

  1. Numerical simulation of wheel wear evolution for heavy haul railway

    Institute of Scientific and Technical Information of China (English)

    王璞; 高亮

    2015-01-01

    The prediction of the wheel wear is a fundamental problem in heavy haul railway. A numerical methodology is introduced to simulate the wheel wear evolution of heavy haul freight car. The methodology includes the spatial coupling dynamics of vehicle and track, the three-dimensional rolling contact analysis of wheel-rail, the Specht’s material wear model, and the strategy for reproducing the actual operation conditions of railway. The freight vehicle is treated as a full 3D rigid multi-body model. Every component is built detailedly and various contact interactions between parts are accurately simulated, taking into account the real clearances. The wheel−rail rolling contact calculation is carried out based on Hertz’s theory and Kalker’s FASTSIM algorithm. The track model is built based on field measurements. The material loss due to wear is evaluated according to the Specht’s model in which the wear coefficient varies with the wear intensity. In order to exactly reproduce the actual operating conditions of railway, dynamic simulations are performed separately for all possible track conditions and running velocities in each iterative step. Dimensionless weight coefficients are introduced that determine the ratios of different cases and are obtained through site survey. For the wheel profile updating, an adaptive step strategy based on the wear depth is introduced, which can effectively improve the reliability and stability of numerical calculation. At last, the wear evolution laws are studied by the numerical model for different wheels of heavy haul freight vehicle running in curves. The results show that the wear of the front wheelset is more serious than that of the rear wheelset for one bogie, and the difference is more obvious for the outer wheels. The wear of the outer wheels is severer than that of the inner wheels. The wear of outer wheels mainly distributes near the flange and the root;while the wear of inner wheels mainly distributes around the

  2. Damage evolution assessment and modeling for CBN grinding wheel wear

    OpenAIRE

    YU, TIANYU; Bastawros, Ashraf F; Chandra, Abhijit

    2014-01-01

    The wear rate of a grinding wheel directly affects the workpiece surface integrity and tolerances. This paper summarizes a combined experimental-modeling framework for life expectancy of an electroplated Cubic Boron Nitride (CBN) grinding wheel, typically utilized in nickel-based superalloy grinding. The article presents an experimental framework to facilitate the formulation of a micromechanics based modeling framework. The presented study investigates the topological evolution of the grindi...

  3. High Speed, Low Weight Momentum/Reaction Wheels

    OpenAIRE

    Wilhide, Larry; Brothers, Louis; Breyer, Eugene

    1999-01-01

    Advancements in several critical areas have made possible lightweight, strong and highly reliable momentum / reaction wheels. The development of reliable bearings with design features that allow high speed operation for space flight applications has significantly altered the weight / speed / wheel design considerations. Current designs typically operate at speeds at or below 6,000 RPM The new retainerless can achieve speeds 10 times that and meet or improve all other significant bearing opera...

  4. The influence of different steering systems on a wheel slip

    Directory of Open Access Journals (Sweden)

    D. Stajnko

    2012-12-01

    Full Text Available Purpose: Modern and advanced mountain tractor allows four different modes of steering wheels: front wheels, back wheels, four wheels and crab steering. The current paper presents the impact of different ways of steering to control the slip in the work transverse on the steep hill slope (39.08%. Design/methodology/approach: For each mode of steering eight measurements were made; four measurements at a forecasted speed of 0.69 m/s and four measurements at a speed of 1.39 m/s. During the two of four measurements the travelling direction was from the left to the right, and vice versa.Findings: The measured slip depended significantly on the steering system, while the driving direction did not cause any differences in the slip.Research limitations/implications: The experiment results presented herein can be applied only with the similar mountain tractors, which allows four different modes of steering wheels. Additional limitation represents the working polygon and the growing conditions of grass.Practical implications: The crab - steering resulted in the smallest slip (5.96% at the average driving speed of 1.08 m/s. When steering with all four wheels, the slip at the average speed of 1.03 m/s increased to 7.27%. The biggest slip was measured when steering with only front wheels was applied. In this case the slip was 8.07% at the average speed of 1.01 m/s.Originality/value: The findings from our experiments indicated that it is very useful to have all wheels steering tractor when working on step slope, because it is grass friendly, offers bigger agility of tractor and improve the safety of the operator.

  5. Electric Power Controller for Steering Wheel Management in Electric Cars

    OpenAIRE

    Milanés, Vicente; Pérez Rastelli, Joshué; Onieva, Enrique; González, Carlos; Pedro, Teresa de

    2009-01-01

    International audience Driverless driving is one of the most interesting topics in the field of the intelligent transportation systems. Among these topics, the automation of the actuators involved in the management of a car, and out of them the control of the steering wheel constitute one of the most complex. In this paper, automatic power steering architecture to manage the steering wheel via Ethernet controller is developed. An on-board PC is connected to the controller to permit handlin...

  6. Big bang nucleosynthesis

    International Nuclear Information System (INIS)

    We present an overview of the standard model of big bang nucleosynthesis (BBN), which describes the production of the light elements in the early universe. The theoretical prediction for the abundances of D, 3He, 4He, and 7Li is discussed. We emphasize the role of key nuclear reactions and the methods by which experimental cross section uncertainties are propagated into uncertainties in the predicted abundances. The observational determination of the light nuclides is also discussed. Particular attention is given to the comparison between the predicted and observed abundances, which yields a measurement of the cosmic baryon content. The spectrum of anisotropies in the cosmic microwave background (CMB) now independently measures the baryon density to high precision; we show how the CMB data test BBN, and find that the CMB and the D and 4He observations paint a consistent picture. This concordance stands as a major success of the hot big bang. On the other hand, 7Li remains discrepant with the CMB-preferred baryon density; possible explanations are reviewed. Finally, moving beyond the standard model, primordial nucleosynthesis constraints on early universe and particle physics are also briefly discussed

  7. Big Rock Point

    International Nuclear Information System (INIS)

    The Big Rock Point Nuclear Plant is the second oldest operating nuclear power plant in the United States. Its 25-yr history is an embodiment of the history of commercial nuclear power. In some respects, its situation today - 5 yr past the midpoint of its design life - can provide operators of other nuclear plants a glimpse of where they will be in another decade. Construction on Big Rock Point began in 1960. It was completed just 2 1/2 yr later at a cost of $27 million. The plant is a General Electric (GE)-designed boiling water direct cycle, forced circulation, high power density reactor. Its construction was undertaken by Consumers Power under the third round of the U.S. Atomic Energy Commission's (AEC's) Power Demonstration Reactor Program. It was an advanced version of GE's Vallecitos boiling water reactor. The plant's fuel was GE's responsibility and, under contract with the AEC, it conducted a fuel research and development (RandD) program involving the plant. Although the plant was designed for research - its original electrical capacity was set at 50 MW(electric) - the unit was subsequently uprated to 69 MW(net electric). The original plant staff included only 44 people and minimal security. Mirroring the industry experience, the number of people on-site had quadrupled

  8. Railway ground vibrations induced by wheel and rail singular defects

    Science.gov (United States)

    Kouroussis, Georges; Connolly, David P.; Alexandrou, Georgios; Vogiatzis, Konstantinos

    2015-10-01

    Railway local irregularities are a growing source of ground-borne vibration and can cause negative environmental impacts, particularly in urban areas. Therefore, this paper analyses the effect of railway track singular defects (discontinuities) on ground vibration generation and propagation. A vehicle/track/soil numerical railway model is presented, capable of accurately predicting vibration levels. The prediction model is composed of a multibody vehicle model, a flexible track model and a finite/infinite element soil model. Firstly, analysis is undertaken to assess the ability of wheel/rail contact models to accurately simulate the force generation at the wheel/rail contact, in the presence of a singular defect. It is found that, although linear contact models are sufficient for modelling ground vibration on smooth tracks, when singular defects are present higher accuracy wheel/rail models are required. Furthermore, it is found that the variation in wheel/rail force during the singular defect contact depends on the track flexibility, and thus requires a fully coupled vehicle/track/foundation model. Next, a parametric study of ground vibrations generated by singular rail and wheel defects is undertaken. Six shapes of discontinuity are modelled, representing various defect types such as transition zones, switches, crossings, rail joints and wheel flats. The vehicle is modelled as an AM96 train set and it is found that ground vibration levels are highly sensitive to defect height, length and shape.

  9. Optimization of Angular-Momentum Biases of Reaction Wheels

    Science.gov (United States)

    Lee, Clifford; Lee, Allan

    2008-01-01

    RBOT [RWA Bias Optimization Tool (wherein RWA signifies Reaction Wheel Assembly )] is a computer program designed for computing angular momentum biases for reaction wheels used for providing spacecraft pointing in various directions as required for scientific observations. RBOT is currently deployed to support the Cassini mission to prevent operation of reaction wheels at unsafely high speeds while minimizing time in undesirable low-speed range, where elasto-hydrodynamic lubrication films in bearings become ineffective, leading to premature bearing failure. The problem is formulated as a constrained optimization problem in which maximum wheel speed limit is a hard constraint and a cost functional that increases as speed decreases below a low-speed threshold. The optimization problem is solved using a parametric search routine known as the Nelder-Mead simplex algorithm. To increase computational efficiency for extended operation involving large quantity of data, the algorithm is designed to (1) use large time increments during intervals when spacecraft attitudes or rates of rotation are nearly stationary, (2) use sinusoidal-approximation sampling to model repeated long periods of Earth-point rolling maneuvers to reduce computational loads, and (3) utilize an efficient equation to obtain wheel-rate profiles as functions of initial wheel biases based on conservation of angular momentum (in an inertial frame) using pre-computed terms.

  10. In-wheel hub SRM simulation and analysis

    Science.gov (United States)

    Sager, Milton W., III

    Is it feasible to replace the conventional gasoline engine and subsequent drive system in a motorcycle with an electric switched reluctance motor (SRM) by placing the SRM inside the rear wheel, thereby removing the need for things such as a clutch, chain, transmission, gears and sprockets? The goal of this thesis is to study the theoretical aspect of prototyping and analyzing an in-wheel electric hub motor to replace the standard gasoline engine traditionally found on motorcycles. With the recent push for clean energy, electric vehicles are becoming more common. All currently produced electric motorcycles use conventional, prefabricated electric motors connected to the traditional sprocket and chain design. This greatly restricts the efficiency and range of these motorcycles. My design stands apart by turning the rear wheel into a SRM which uses electromagnets around a non-magnetic core to convert electrical energy into mechanical force driving the rear wheel. To my knowledge, there is currently no motorcycle designed with an in-wheel hub SRM. A three-phase SRM and a five-phase SRM will be simulated and analyzed using MATLAB with Simulink. Factors such as friction, weight, power, etc. will be taken into account in order to create a realistic simulation as if it were inside the rear wheel of a motorcycle. Since time and finances will not allow for a full scale build, a scaled model three-phase SRM will be attempted for demonstration purposes.

  11. Paper recycling framework, the "Wheel of Fiber".

    Science.gov (United States)

    Ervasti, Ilpo; Miranda, Ruben; Kauranen, Ilkka

    2016-06-01

    At present, there is no reliable method in use that unequivocally describes paper industry material flows and makes it possible to compare geographical regions with each other. A functioning paper industry Material Flow Account (MFA) that uses uniform terminology and standard definitions for terms and structures is necessary. Many of the presently used general level MFAs, which are called frameworks in this article, stress the importance of input and output flows but do not provide a uniform picture of material recycling. Paper industry is an example of a field in which recycling plays a key role. Additionally, terms related to paper industry recycling, such as collection rate, recycling rate, and utilization rate, are not defined uniformly across regions and time. Thus, reliably comparing material recycling activity between geographical regions or calculating any regional summaries is difficult or even impossible. The objective of this study is to give a partial solution to the problem of not having a reliable method in use that unequivocally describes paper industry material flows. This is done by introducing a new material flow framework for paper industry in which the flow and stage structure supports the use of uniform definitions for terms related to paper recycling. This new framework is termed the Detailed Wheel of Fiber. PMID:26994970

  12. 2015 Philip S. Portoghese Medicinal Chemistry Lectureship. Curing Hepatitis C Virus Infection with Direct-Acting Antiviral Agents: The Arc of a Medicinal Chemistry Triumph.

    Science.gov (United States)

    Meanwell, Nicholas A

    2016-08-25

    The development of direct-acting antiviral agents that can cure a chronic hepatitis C virus (HCV) infection after 8-12 weeks of daily, well-tolerated therapy has revolutionized the treatment of this insidious disease. In this article, three of Bristol-Myers Squibb's HCV programs are summarized, each of which produced a clinical candidate: the NS3 protease inhibitor asunaprevir (64), marketed as Sunvepra, the NS5A replication complex inhibitor daclatasvir (117), marketed as Daklinza, and the allosteric NS5B polymerase inhibitor beclabuvir (142), which is in late stage clinical studies. A clinical study with 64 and 117 established for the first time that a chronic HCV infection could be cured by treatment with direct-acting antiviral agents alone in the absence of interferon. The development of small molecule HCV therapeutics, designed by medicinal chemists, has been hailed as "the arc of a medical triumph" but may equally well be described as "the arc of a medicinal chemistry triumph". PMID:27501244

  13. Residual stresses in railway wheels and their effect on damage rates through the life of a wheel

    OpenAIRE

    Molyneux-Berry, Paul; Bevan, Adam

    2013-01-01

    Wheelset maintenance and renewal comprises a significant portion of the whole-life cost of railway rolling stock. At present, many GB passenger trains have their wheels turned on a lathe at regular intervals to prevent the propagation of Rolling Contact Fatigue (RCF) cracks in the rim. Evidence from a number of fleets suggests that RCF damage occurs much more quickly as the wheelsets near the end of their life. Wheel manufacturing processes are intended to induce a compressive hoop stress in ...

  14. Passport to the Big Bang

    CERN Multimedia

    De Melis, Cinzia

    2013-01-01

    Le 2 juin 2013, le CERN inaugure le projet Passeport Big Bang lors d'un grand événement public. Affiche et programme. On 2 June 2013 CERN launches a scientific tourist trail through the Pays de Gex and the Canton of Geneva known as the Passport to the Big Bang. Poster and Programme.

  15. IZVEDBENI ELEMENTI U BIG BROTHERU

    OpenAIRE

    Radman, Korana

    2009-01-01

    Big Brother publici nudi "ultimativnu stvarnost" osiguranu cjelodnevnim nadzorom televizijskih kamera, o čemu je polemizirano od početka njegova prikazivanja u Europi i svijetu. Imajući to na umu, ovaj rad je pristupio Big Brotheru iz perspektive izvedbenih studija, pokušavajući u njemu prepoznati neke od mogućih izvedbi.

  16. The Big Read: Case Studies

    Science.gov (United States)

    National Endowment for the Arts, 2009

    2009-01-01

    The Big Read evaluation included a series of 35 case studies designed to gather more in-depth information on the program's implementation and impact. The case studies gave readers a valuable first-hand look at The Big Read in context. Both formal and informal interviews, focus groups, attendance at a wide range of events--all showed how…

  17. Resources: Building Big (and Small)

    OpenAIRE

    Kelley, Todd R.

    2007-01-01

    The article offers a set of videos and web resources for elementary teachers to help them explore five different structures, including bridges, domes, skyscrapers, dams, and tunnels, that have been built big to meet the human needs and wants. It includes the miniseries video "Building Big" by David Macaulay and the website www.pbs.org/buildingbig.com.

  18. Torque blending and wheel slip control in EVs with in-wheel motors

    Science.gov (United States)

    de Castro, Ricardo; Araújo, Rui E.; Tanelli, Mara; Savaresi, Sergio M.; Freitas, Diamantino

    2012-01-01

    Among the many opportunities offered by electric vehicles (EVs), the design of power trains based on in-wheel electric motors represents, from the vehicle dynamics point of view, a very attractive prospect, mainly due to the torque-vectoring capabilities. However, this distributed propulsion also poses some practical challenges, owing to the constraints arising from motor installation in a confined space, to the increased unsprung mass weight and to the integration of the electric motor with the friction brakes. This last issue is the main theme of this work, which, in particular, focuses on the design of the anti-lock braking system (ABS). The proposed structure for the ABS is composed of a tyre slip controller, a wheel torque allocator and a braking supervisor. To address the slip regulation problem, an adaptive controller is devised, offering robustness to uncertainties in the tyre-road friction and featuring a gain-scheduling mechanism based on the vehicle velocity. Further, an optimisation framework is employed in the torque allocator to determine the optimal split between electric and friction brake torque based on energy performance metrics, actuator constraints and different actuators bandwidth. Finally, based on the EV working condition, the priorities of this allocation scheme are adapted by the braking supervisor unit. Simulation results obtained with the CarSim vehicle model, demonstrate the effectiveness of the overall approach.

  19. Control for 4-Wheel Individual Steering and 4-Wheel Driving Electronic Vehicle

    Science.gov (United States)

    Oshima, Hiroyasu; Tani, Masashi; Kobayashi, Nobuaki; Ishii, Akira; Imai, Katsuya

    An indoor 4-wheel individual steering and driving vehicle with full electronics was built for evaluating the system ability and the performance in practical use. Mechanical parts such as the connecting rod and the differential gear are not provided for this vehicle. From trial operation, the characteristics are fully performed as in design, but some problems that originated from the design concept are disclosed. Rotating radius (R) of the vehicle was taken for steering command parameter, but it was found that it is not an appropriate parameter for driving operation. The reasons are as follows 1) R has much different sense of driving conformability for the driver, because it doesn’t refer to the running direction, but to the rotating radius of crosswise direction. 2) Sensitivity of each wheel steering angle against R differs over double figures in full range of R. 3) R changed from plus to minus and also the other way in most practical situations around go-straight operation. For these reasons, the steering command parameter was changed from R to α, where α is the angle between vehicle lengthwise direction and the moving direction. The steering control algorithm using α parameter has been proven to solve the above mentioned problems 1), 2), and 3).

  20. Big Bounce Genesis

    CERN Document Server

    Li, Changhong; Cheung, Yeuk-Kwan E

    2014-01-01

    We report on the possibility to use dark matter mass and its interaction cross section as a smoking gun signal of the existence of a big bounce at the early stage in the evolution of our currently observed universe. A model independent study of dark matter production in the contraction and expansion phases of the bounce universe reveals a new venue for achieving the observed relic abundance in which a significantly smaller amount of dark matter--compared to the standard cosmology--is produced and survives until today, diluted only by the cosmic expansion since the radiation dominated era. Once DM mass and its interaction strength with ordinary matter are determined by experiments, this alternative route becomes a signature of the bounce universe scenario.

  1. A matrix big bang

    International Nuclear Information System (INIS)

    The light-like linear dilaton background represents a particularly simple time-dependent 1/2 BPS solution of critical type-IIA superstring theory in ten dimensions. Its lift to M-theory, as well as its Einstein frame metric, are singular in the sense that the geometry is geodesically incomplete and the Riemann tensor diverges along a light-like subspace of codimension one. We study this background as a model for a big bang type singularity in string theory/M-theory. We construct the dual Matrix theory description in terms of a (1+1)-d supersymmetric Yang-Mills theory on a time-dependent world-sheet given by the Milne orbifold of (1+1)-d Minkowski space. Our model provides a framework in which the physics of the singularity appears to be under control

  2. A Matrix Big Bang

    CERN Document Server

    Craps, B; Verlinde, E; Craps, Ben; Sethi, Savdeep; Verlinde, Erik

    2005-01-01

    The light-like linear dilaton background represents a particularly simple time-dependent 1/2 BPS solution of critical type IIA superstring theory in ten dimensions. Its lift to M-theory, as well as its Einstein frame metric, are singular in the sense that the geometry is geodesically incomplete and the Riemann tensor diverges along a light-like subspace of codimension one. We study this background as a model for a big bang type singularity in string theory/M-theory. We construct the dual Matrix theory description in terms of a (1+1)-d supersymmetric Yang-Mills theory on a time-dependent world-sheet given by the Milne orbifold of (1+1)-d Minkowski space. Our model provides a framework in which the physics of the singularity appears to be under control.

  3. Big nuclear accidents

    International Nuclear Information System (INIS)

    Much of the debate on the safety of nuclear power focuses on the large number of fatalities that could, in theory, be caused by extremely unlikely but imaginable reactor accidents. This, along with the nuclear industry's inappropriate use of vocabulary during public debate, has given the general public a distorted impression of the safety of nuclear power. The way in which the probability and consequences of big nuclear accidents have been presented in the past is reviewed and recommendations for the future are made including the presentation of the long-term consequences of such accidents in terms of 'reduction in life expectancy', 'increased chance of fatal cancer' and the equivalent pattern of compulsory cigarette smoking. (author)

  4. DPF Big One

    International Nuclear Information System (INIS)

    At its latest venue at Fermilab from 10-14 November, the American Physical Society's Division of Particles and Fields meeting entered a new dimension. These regular meetings, which allow younger researchers to communicate with their peers, have been gaining popularity over the years (this was the seventh in the series), but nobody had expected almost a thousand participants and nearly 500 requests to give talks. Thus Fermilab's 800-seat auditorium had to be supplemented with another room with a video hookup, while the parallel sessions were organized into nine bewildering streams covering fourteen major physics topics. With the conventionality of the Standard Model virtually unchallenged, physics does not move fast these days. While most of the physics results had already been covered in principle at the International Conference on High Energy Physics held in Dallas in August (October, page 1), the Fermilab DPF meeting had a very different atmosphere. Major international meetings like Dallas attract big names from far and wide, and it is difficult in such an august atmosphere for young researchers to find a receptive audience. This was not the case at the DPF parallel sessions. The meeting also adopted a novel approach, with the parallels sandwiched between an initial day of plenaries to set the scene, and a final day of summaries. With the whole world waiting for the sixth ('top') quark to be discovered at Fermilab's Tevatron protonantiproton collider, the meeting began with updates from Avi Yagil and Ronald Madaras from the big detectors, CDF and DO respectively. Although rumours flew thick and fast, the Tevatron has not yet reached the top, although Yagil could show one intriguing event of a type expected from the heaviest quark

  5. Applied design methodology for lunar rover elastic wheel

    Science.gov (United States)

    Cardile, Diego; Viola, Nicole; Chiesa, Sergio; Rougier, Alessandro

    2012-12-01

    In recent years an increasing interest in the Moon surface operations has been experienced. In the future robotic and manned missions of Moon surface exploration will be fundamental in order to lay the groundwork for more ambitious space exploration programs. Surface mobility systems will be the key elements to ensure an efficient and safe Moon exploration. Future lunar rovers are likely to be heavier and able to travel longer distances than the previously developed Moon rover systems. The Lunar Roving Vehicle (LRV) is the only manned rover, which has so far been launched and used on the Moon surface. Its mobility system included flexible wheels that cannot be scaled to the heavier and longer range vehicles. Thus the previously developed wheels are likely not to be suitable for the new larger vehicles. Taking all these considerations into account, on the basis of the system requirements and assumptions, several wheel concepts have been discussed and evaluated through a trade-off analysis. Semi-empirical equations have been utilized to predict the wheel geometrical characteristics, as well as to estimate the motion resistances and the ability of the system to generate thrust. A numerical model has also been implemented, in order to define more into the details the whole wheel design, in terms of wheel geometry and physical properties. As a result of the trade-off analysis, the ellipse wheel concept has shown the best behavior in terms of stiffness, mass budget and dynamic performance. The results presented in the paper have been obtained in cooperation with Thales Alenia Space-Italy and Sicme motori, in the framework of a regional program called STEPS . STEPS-Sistemi e Tecnologie per l'EsPlorazione Spaziale is a research project co-financed by Piedmont Region and firms and universities of the Piedmont Aerospace District in the ambit of the P.O.R-F.E.S.R. 2007-2013 program.

  6. Investigation of the Wheel-Flange Lubrication of Railway Trains

    International Nuclear Information System (INIS)

    A tracer method was applied to investigate the wheel-flange lubrication action of the new Austrian multiple-unit train ''Transalpin''. On electric engines the flanges of the first pair of wheels are lubricated by a pendulum oil pump. This pump starts to work when there is lateral movement of the engine in curves or at high speed on straight lines. The lubricating oil is transferred, while the train is underway, from the first wheel to the inner surface of the rail. From there it should be taken up by the following wheels of the train. In this way the friction between the rails and the wheel flanges can be reduced and as a consequence the wear of material is decreased. Until the present investigation it has not been possible to get quantitative information about the action of this type of lubrication. By adding the tracer 198Au in the form of a colloid to the lubricating oil (specific activity 0.5 Ci/litre), quantitative measurements of the oil transport mechanism could be made on the moving train. The detection of the labelled lubricant was possible even on the last wheels of a train of 44 axles. The oil films which were still detectable on the wheel flanges had a thickness of about 0. 3 microns. By this tracer method, the dependence of lubrication on the speed and the line conditions can also be determined. The tracer method has a wide range of applications in the study of underway conditions in railroad operation including the investigation of the sine movement of trains. (author)

  7. Mining “Big Data” using Big Data Services

    OpenAIRE

    2014-01-01

    While many colleagues within science are fed up with the “big data fad”, empirical analyses we conducted for the current editorial actually show an inconsistent picture: we use big data services to determine whether there really is an increase in writing about big data or even widespread use of the term. Google Correlate (http://www.google.com/trends/correlate/), the first free tool we are presenting here, doesn’t list the term, showing that number of searches for it are below an absolute min...

  8. Big bang and big crunch in matrix string theory

    International Nuclear Information System (INIS)

    Following the holographic description of linear dilaton null cosmologies with a big bang in terms of matrix string theory put forward by Craps, Sethi, and Verlinde, we propose an extended background describing a universe including both big bang and big crunch singularities. This belongs to a class of exact string backgrounds and is perturbative in the string coupling far away from the singularities, both of which can be resolved using matrix string theory. We provide a simple theory capable of describing the complete evolution of this closed universe

  9. Economic efficiency, independent power producers and wheeling

    International Nuclear Information System (INIS)

    Traditionally, electric utilities have sought to decrease the cost of production by such means as merit order running of machines, by improving equipment efficiency, by fuel mix, by interconnection and exchange of cheap energy, and by unit participation and firm purchase and sale contracts for long term savings. In the ''new look'', it was suggested that financial and technical competition is not enough, and that economic gains could be achieved through fostering independent power producers, i.e., non-utility generators (NUG's), greater exchanges of economy energy, unrestricted access to the transmission network for moving cheap energy through facilities of third parties, and by bidding to supply energy to non-generators, etc. Naturally, the proposals to change the comfortable and time-hallowed practices by which utility business had been carried out in the past has created an ongoing debate both pro and con, much of it acrimonious, and, unfortunately, some of it ill-informed. The turmoil in the political context impacts on a utility's technical and financial planners, and on their managements, all of whom contribute to justifying and maintaining the flow of capital to the industry and energy to the customer. They must now seek new ways to implement both short- and long-term planning of power supply. Some of the factors that were neglected in the past will demand more attention in the future. This paper discusses some of the costs that, under the anticipated modus operandi, must be integrated into the planning process while meeting the new challenges. The costs are those relating to third-parties, costs of transmission constraints, and costs of wheeling. The opinion is ventured that much of the efficiency improvement anticipated during the debate has already been achieved by conscientious utility managements. (author)

  10. Electric pulse treatment of rim wheel metal after operation

    Directory of Open Access Journals (Sweden)

    L.I.Vakulenko

    2013-02-01

    Full Text Available Introduction. Load increase on the wheel pair ax requires the use of railway wheels with the advanced complex of properties. Except strength properties, the properties of metal resistance to defect nucleation on the wheel thread are of high importance. The above mentioned properties increase is possible by using different technological decisions: alloying and heat strengthening. Purpose. The purpose is an attempt to estimate the softening degree of the wheel thread metal using the electric pulse treatment. Methodology. Electric pulse treatment (ET was carried out on the special plant in the conditions of JSC DS (Nikolayev city. As the property of metal strength the Vickers hardness number is used. The microstructure research was carried out using the light microscope. The material for research is the carbon steel of the rim fragment of railway wheel №181732, withdrawn after operation, containing 0,55%С, 0,74%Mn, 0,33%Si, 0,009%P, 0,01%S, 0,06% Ni, 0,1%Cr, 0,08%Cu. Findings. Exposing the rim fragment to electric pulse treatment (ET, the qualitative changes of internal structure of the wheel rim metal corresponded to the experimentally observed geometrical dimensions change of the specimen, depending on the cycles number. As a result of the treatment the reduction of cold strained metal hardness is observed. It was found out 20 % softening on the wheel thread for the І rim area the, for the ІІ rim area the 8% softening and for the ІІІ 11% softening in relation to the initial state. Originality. As a result of electric pulse treatment, the change of the specimen geometrical dimensions is observed. Depending on the number of cycles it causes softening effect. It is proved that the observed softening value during ET is qualitatively connected with the cold strain level on the rail wheel thread. Practical value. As a result of metal cold work on the wheel thread its resistance to the defect nucleation is being reduced. The resulted data can

  11. Evaluation of wheel dampers on an intercity train

    Science.gov (United States)

    Färm, J.

    2003-10-01

    Pass-by noise from high-speed trains is one important area that has to be handled in all new train projects. For the new line between Oslo and the Gardemoen Airport which opened in 1998, very stringent requirements were set out regarding external noise. To reach the target it was decided that the train should be equipped with wheel dampers. Two different types of wheel dampers were used on the train; a ring damper was mounted on the wheels of the driven bogies, whilst plate dampers divided into tuned absorber fins were mounted on the wheels of the trailer bogies. During the type testing of the Airport Express Train, additional measurements were performed in order to evaluate the acoustic effect of the plate wheel dampers. Two test series were performed with the same train set; first with the train in standard configuration and secondly with the wheel dampers removed from the second and third bogie. The external noise was measured at 5 and 25 m distance from the centre of the track at speeds ranging from 80 to 200 km/h. The third-octave filtered time histories were analyzed to calculate the effect of the wheel dampers. As expected, there was a significant reduction of 4-6 dB at frequencies above 2000 Hz, but there was also a reduction of 2 dB for frequencies as low as 800 Hz. This reduction was also found in the parts of the time histories when the rail should be dominating. This implies that the wheel dampers also reduce the rail noise. The total rolling noise reduction for the trailer bogie was 3 dB at 200 km/h and 1 dB at 80 km/h. From comparison with TWINS-calculated sound power levels it was estimated that the wheel noise would be reduced by 5 dB and the rail noise would be reduced by 1 dB at 200 km/h.

  12. Parametric study of wheel transitions at railway crossings

    Science.gov (United States)

    Wan, C.; Markine, V. L.

    2015-12-01

    Vehicle-track interaction at railway crossings is complex due to the discontinuity of the crossings. In this study, the effect of the local crossing geometry, the track alignment, and the wheel profiles on the wheel transition behaviour is investigated using the multi-body system software package VI-Rail. The transition behaviour is evaluated based on the location of the transition point along the crossing (and the location of impact), the contact pressure and the energy dissipation during the wheel-rail contact. A detailed parametric study of the crossing geometry has been performed, through which the most effective parameters for defining the crossing geometry are identified. These parameters are the cross-sectional shape of the nose rail, which can be tuned by one variable, and the vertical distance between the top of the wing rail and the nose rail. Additionally, a parametric study on the interaction influence of the crossing geometry, the track alignment and the wheel profile is performed using the design of experiments method with a two-level full factorial design. The longitudinal height profile of the crossing and the wheel profile are the most significant factors.

  13. BigOP: Generating Comprehensive Big Data Workloads as a Benchmarking Framework

    OpenAIRE

    Zhu, Yuqing; Zhan, Jianfeng; Weng, Chuliang; Nambiar, Raghunath; Zhang, Jinchao; Chen, Xingzhen; Wang, Lei

    2014-01-01

    Big Data is considered proprietary asset of companies, organizations, and even nations. Turning big data into real treasure requires the support of big data systems. A variety of commercial and open source products have been unleashed for big data storage and processing. While big data users are facing the choice of which system best suits their needs, big data system developers are facing the question of how to evaluate their systems with regard to general big data processing needs. System b...

  14. From big bang to big crunch and beyond

    International Nuclear Information System (INIS)

    We study a quotient Conformal Field Theory, which describes a 3+1 dimensional cosmological spacetime. Part of this spacetime is the Nappi-Witten (NW) universe, which starts at a 'big bang' singularity, expands and then contracts to a 'big crunch' singularity at a finite time. The gauged WZW model contains a number of copies of the NW spacetime, with each copy connected to the preceding one and to the next one at the respective big bang/big crunch singularities. The sequence of NW spacetimes is further connected at the singularities to a series of non-compact static regions with closed timelike curves. These regions contain boundaries, on which the observables of the theory live. This suggests a holographic interpretation of the physics. (author)

  15. The challenges of big data.

    Science.gov (United States)

    Mardis, Elaine R

    2016-05-01

    The largely untapped potential of big data analytics is a feeding frenzy that has been fueled by the production of many next-generation-sequencing-based data sets that are seeking to answer long-held questions about the biology of human diseases. Although these approaches are likely to be a powerful means of revealing new biological insights, there are a number of substantial challenges that currently hamper efforts to harness the power of big data. This Editorial outlines several such challenges as a means of illustrating that the path to big data revelations is paved with perils that the scientific community must overcome to pursue this important quest. PMID:27147249

  16. Big Data Mining: Tools & Algorithms

    Directory of Open Access Journals (Sweden)

    Adeel Shiraz Hashmi

    2016-03-01

    Full Text Available We are now in Big Data era, and there is a growing demand for tools which can process and analyze it. Big data analytics deals with extracting valuable information from that complex data which can’t be handled by traditional data mining tools. This paper surveys the available tools which can handle large volumes of data as well as evolving data streams. The data mining tools and algorithms which can handle big data have also been summarized, and one of the tools has been used for mining of large datasets using distributed algorithms.

  17. Google BigQuery analytics

    CERN Document Server

    Tigani, Jordan

    2014-01-01

    How to effectively use BigQuery, avoid common mistakes, and execute sophisticated queries against large datasets Google BigQuery Analytics is the perfect guide for business and data analysts who want the latest tips on running complex queries and writing code to communicate with the BigQuery API. The book uses real-world examples to demonstrate current best practices and techniques, and also explains and demonstrates streaming ingestion, transformation via Hadoop in Google Compute engine, AppEngine datastore integration, and using GViz with Tableau to generate charts of query results. In addit

  18. The challenges of big data

    Science.gov (United States)

    2016-01-01

    ABSTRACT The largely untapped potential of big data analytics is a feeding frenzy that has been fueled by the production of many next-generation-sequencing-based data sets that are seeking to answer long-held questions about the biology of human diseases. Although these approaches are likely to be a powerful means of revealing new biological insights, there are a number of substantial challenges that currently hamper efforts to harness the power of big data. This Editorial outlines several such challenges as a means of illustrating that the path to big data revelations is paved with perils that the scientific community must overcome to pursue this important quest. PMID:27147249

  19. Big Data: present and future

    Directory of Open Access Journals (Sweden)

    Mircea Raducu TRIFU

    2014-05-01

    Full Text Available The paper explains the importance of the Big Data concept, a concept that even now, after years of development, is for the most companies just a cool keyword. The paper also describes the level of the actual big data development and the things it can do, and also the things that can be done in the near future. The paper focuses on explaining to nontechnical and non-database related technical specialists what basically is big data, presents the three most important V's, as well as the new ones, the most important solutions used by companies like Google or Amazon, as well as some interesting perceptions based on this subject.

  20. Detecting and understanding big events in big cities

    OpenAIRE

    Furletti, Barbara; Trasarti, Roberto; Gabrielli, Lorenzo; Smoreda, Zbigniew; Vanhoof, Maarten; Ziemlicki, Cezary

    2015-01-01

    Recent studies have shown the great potential of big data such as mobile phone location data to model human behavior. Big data allow to analyze people presence in a territory in a fast and effective way with respect to the classical surveys (diaries or questionnaires). One of the drawbacks of these collection systems is incompleteness of the users' traces; people are localized only when they are using their phones. In this work we define a data mining method for identifying people presence an...

  1. Antigravity and the big crunch/big bang transition

    OpenAIRE

    Bars, Itzhak; Chen, Shih-Hung; Steinhardt, Paul J.(Princeton Center for Theoretical Science, Princeton University, Princeton, NJ, 08544, USA); Turok, Neil

    2011-01-01

    We point out a new phenomenon which seems to be generic in 4d effective theories of scalar fields coupled to Einstein gravity, when applied to cosmology. A lift of such theories to a Weyl-invariant extension allows one to define classical evolution through cosmological singularities unambiguously, and hence construct geodesically complete background spacetimes. An attractor mechanism ensures that, at the level of the effective theory, generic solutions undergo a big crunch/big bang transition...

  2. Quantum Fields in a Big Crunch/Big Bang Spacetime

    OpenAIRE

    Tolley, Andrew J.; Turok, Neil

    2002-01-01

    We consider quantum field theory on a spacetime representing the Big Crunch/Big Bang transition postulated in the ekpyrotic or cyclic cosmologies. We show via several independent methods that an essentially unique matching rule holds connecting the incoming state, in which a single extra dimension shrinks to zero, to the outgoing state in which it re-expands at the same rate. For free fields in our construction there is no particle production from the incoming adiabatic vacuum. When interacti...

  3. Sailing through the big crunch-big bang transition

    OpenAIRE

    Bars, Itzhak; Steinhardt, Paul; Turok, Neil

    2013-01-01

    In a recent series of papers, we have shown that theories with scalar fields coupled to gravity (e.g., the standard model) can be lifted to a Weyl-invariant equivalent theory in which it is possible to unambiguously trace the classical cosmological evolution through the transition from big crunch to big bang. The key was identifying a sufficient number of finite, Weyl-invariant conserved quantities to uniquely match the fundamental cosmological degrees of freedom across the transition. In so ...

  4. Hey, big spender

    International Nuclear Information System (INIS)

    Business to business electronic commerce is looming large in the future of the oil industry. It is estimated that by adopting e-commerce the industry could achieve bottom line savings of between $1.8 to $ 3.4 billion a year on annual gross revenues in excess of $ 30 billion. At present there are several teething problems to overcome such as inter-operability standards, which are at least two or three years away. Tying in electronically with specific suppliers is also an expensive proposition, although the big benefits are in fact in doing business with the same suppliers on a continuing basis. Despite these problems, 14 of the world's largest energy and petrochemical companies joined forces in mid-April to create a single Internet procurement marketplace for the industry's complex supply chain. The exchange was designed by B2B (business-to-business) software provider, Commerce One Inc., ; it will leverage the buying clout of these industry giants (BP Amoco, Royal Dutch Shell Group, Conoco, Occidental Petroleum, Phillips Petroleum, Unocal Corporation and Statoil among them), currently about $ 125 billion on procurement per year; they hope to save between 5 to 30 per cent depending on the product and the region involved. Other similar schemes such as Chevron and partners' Petrocosm Marketplace, Network Oil, a Houston-based Internet portal aimed at smaller petroleum companies, are also doing business in the $ 10 billion per annum range. e-Energy, a cooperative project between IBM Ericson and Telus Advertising is another neutral, virtual marketplace targeted at the oil and gas sector. PetroTRAX, a Calgary-based website plans to take online procurement and auction sales a big step forward by establishing a portal to handle any oil company's asset management needs. There are also a number of websites targeting specific needs: IndigoPool.com (acquisitions and divestitures) and WellBid.com (products related to upstream oil and gas operators) are just two examples. All in

  5. Transmission access and retail wheeling. The key questions

    Energy Technology Data Exchange (ETDEWEB)

    Casazza, J.A. [CSA Energy Consultants, Inc., Arlington, VA (United States)

    1996-12-31

    The key questions involving transmission access and retail wheeling are discussed, distinguishing between opposing views regarding the effect on system costs and the environment, particularly on optimal planning involving matching capacity and demand, generation use, demand side management, and economic operations. Also discussed are contrasting views regarding the effect of cost control pressures, regulatory advantages and disadvantages, the impact on system reliability, and the stranding of investment. The author`s key concern is the effect of retail wheeling upon optimal planning and operation i.e., will competitors be willing to provide one another with the cost and technical information required for coordination? In his worst scenario, retail wheeling may lead to substantial production cost increases, lessened reliability, and unfair cost-shifting between customer classes. More optimistically, production costs and reliability may be unaffected and the cost-shifting could be salubrious. 7 figs., 11 refs.

  6. Model Design for Water Wheel Control System of Heumgyeonggaknu

    Science.gov (United States)

    Kim, Sang Hyuk; Ham, Seon Young; Lee, Yong Sam

    2016-03-01

    Heumgyeonggaknu (????) is powered by a water-hammering-type water wheel. The technique that maintains the constant speed of the water wheel is assumed to be the one used in the Cheonhyeong (??? ) apparatus in Shui Yun Yi Xiang Tai (????) made by the Northern Song ( ??) dynasty in the 11th century. We investigated the history of the development and characteristics of the Cheonhyeong apparatus, and we analyzed ways to transmit the power of Heumgyeonggaknu. In addition, we carried out a conceptual design to systematically examine the power control system. Based on the conceptual design, we built a model for a water wheel control system that could be used in experiments by drawing a 3D model and a basic design.

  7. Fuzzy model for predicting the number of deformed wheels

    Directory of Open Access Journals (Sweden)

    Ž. Đorđević

    2015-10-01

    Full Text Available Deformation of the wheels damage cars and rails and affect on vehicle stability and safety. Repair and replacement cause high costs and lack of wagons. Planning of maintenance of wagons can not be done without estimates of the number of wheels that will be replaced due to wear and deformation in a given period of time. There are many influencing factors, the most important are: weather conditions, quality of materials, operating conditions, and distance between the two replacements. The fuzzy logic model uses the collected data as input variables to predict the output variable - number of deformed wheels for a certain type of vehicle in the defined period at a particular section of the railway.

  8. Fabrication of low cost cutting wheel via thermal spray process

    Science.gov (United States)

    Anasyida, A. S.; Nurulakmal, M. S.

    2012-09-01

    The present study is mainly focused on development of metal cutting wheel. The process involved hard particles (abrasives) being bonded on the wheel to enhance the cutting capability by thermal spraying process and followed by polymer bonding. The purpose of this work is to produce low cost cutting wheel and study the performance of cutting behavior. Two different types of powders; silicon carbide (SiC) as bonding agent and chromium carbide (Cr3C2) as abrasives were used. Wear loss and depth of cut as function of load, cutting time and cutting speed were evaluated. The results showed that the speed and load were the main factors that affected the cutting efficiency and the optimum cutting process can be performed at low cutting speed and high load or at high cutting speed and low load.

  9. Transmission access and retail wheeling. The key questions

    International Nuclear Information System (INIS)

    The key questions involving transmission access and retail wheeling are discussed, distinguishing between opposing views regarding the effect on system costs and the environment, particularly on optimal planning involving matching capacity and demand, generation use, demand side management, and economic operations. Also discussed are contrasting views regarding the effect of cost control pressures, regulatory advantages and disadvantages, the impact on system reliability, and the stranding of investment. The author's key concern is the effect of retail wheeling upon optimal planning and operation i.e., will competitors be willing to provide one another with the cost and technical information required for coordination? In his worst scenario, retail wheeling may lead to substantial production cost increases, lessened reliability, and unfair cost-shifting between customer classes. More optimistically, production costs and reliability may be unaffected and the cost-shifting could be salubrious. 7 figs., 11 refs

  10. Big bang darkleosynthesis

    Directory of Open Access Journals (Sweden)

    Gordan Krnjaic

    2015-12-01

    Full Text Available In a popular class of models, dark matter comprises an asymmetric population of composite particles with short range interactions arising from a confined nonabelian gauge group. We show that coupling this sector to a well-motivated light mediator particle yields efficient darkleosynthesis, a dark-sector version of big-bang nucleosynthesis (BBN, in generic regions of parameter space. Dark matter self-interaction bounds typically require the confinement scale to be above ΛQCD, which generically yields large (≫MeV/dark-nucleon binding energies. These bounds further suggest the mediator is relatively weakly coupled, so repulsive forces between dark-sector nuclei are much weaker than Coulomb repulsion between standard-model nuclei, which results in an exponential barrier-tunneling enhancement over standard BBN. Thus, darklei are easier to make and harder to break than visible species with comparable mass numbers. This process can efficiently yield a dominant population of states with masses significantly greater than the confinement scale and, in contrast to dark matter that is a fundamental particle, may allow the dominant form of dark matter to have high spin (S≫3/2, whose discovery would be smoking gun evidence for dark nuclei.

  11. Ant Triumphs Over Elephant

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Lanye, a small beer producer in Zhejiang Province, has won a lawsuit against beverage giant Pepsi over trademark infringement In 2005 Pepsi began launching a massive marketing campaign to promote its soft drink with the theme “Blue Storm.”Contrary to Pep

  12. The triumphs of coke

    Energy Technology Data Exchange (ETDEWEB)

    Mott, R.A.

    2004-07-01

    This is a reproduction of a booklet specially written by Dr R.A. Mott and designed by Mr G.E. Hall to mark the jubilee of the Coke Oven Managers' Association, founded in 1915. Whilst mentioning early methods of making coke in Great Britain, it deals particularly with the many developments in coke usage which took place before 1915 and is complementary to the 'History of coke making' written by Dr Mott in 1936. Uses covered include: for malting, for non-ferrous metal making, in an iron blast furnace, in crucible steel making, in the chafery and puddling process, in a foundry cupola, and in railway locomotives. 15 ills.

  13. The Triumph of Monetarism?

    OpenAIRE

    J. Bradford De Long

    2000-01-01

    The story of 20th century macroeconomics begins with Irving Fisher. In his books Appreciation and Interest (1896), The Rate of Interest (1907), and The Purchasing Power of Money (1911), Fisher fueled the intellectual fire that became known as monetarism. But what has happened to monetarism at the end of the 20th century? The short answer is that much of this current of thought is still there, but its insights pass under another name. We may not all be Keynesians now, but the influence of mone...

  14. The BigBOSS Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Schelgel, D.; Abdalla, F.; Abraham, T.; Ahn, C.; Allende Prieto, C.; Annis, J.; Aubourg, E.; Azzaro, M.; Bailey, S.; Baltay, C.; Baugh, C.; /APC, Paris /Brookhaven /IRFU, Saclay /Marseille, CPPM /Marseille, CPT /Durham U. / /IEU, Seoul /Fermilab /IAA, Granada /IAC, La Laguna

    2011-01-01

    BigBOSS will obtain observational constraints that will bear on three of the four 'science frontier' questions identified by the Astro2010 Cosmology and Fundamental Phyics Panel of the Decadal Survey: Why is the universe accelerating; what is dark matter and what are the properties of neutrinos? Indeed, the BigBOSS project was recommended for substantial immediate R and D support the PASAG report. The second highest ground-based priority from the Astro2010 Decadal Survey was the creation of a funding line within the NSF to support a 'Mid-Scale Innovations' program, and it used BigBOSS as a 'compelling' example for support. This choice was the result of the Decadal Survey's Program Priorization panels reviewing 29 mid-scale projects and recommending BigBOSS 'very highly'.

  15. Big Lake Dam Inspection Report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report summarizes an inspection of the Big Lake Dam that was done in September of 1983. The inspection did not reveal any conditions that constitute and...

  16. Le Big Bang en laboratoire

    CERN Multimedia

    Roy, Christelle

    2006-01-01

    Physiciens have been dreaming of it for 30 years; Thanks to huge particle accelerators, they were able to observe the matter such as it was some instants after the Big Bang (three different articles in 10 pages)

  17. Big Data Analytics in Healthcare

    OpenAIRE

    Ashwin Belle; Raghuram Thiagarajan; S. M. Reza Soroushmehr; Fatemeh Navidi; Daniel A Beard; Kayvan Najarian

    2015-01-01

    The rapidly expanding field of big data analytics has started to play a pivotal role in the evolution of healthcare practices and research. It has provided tools to accumulate, manage, analyze, and assimilate large volumes of disparate, structured, and unstructured data produced by current healthcare systems. Big data analytics has been recently applied towards aiding the process of care delivery and disease exploration. However, the adoption rate and research development in this space is sti...

  18. Big Data and Ambulatory Care

    OpenAIRE

    Thorpe, Jane Hyatt; Gray, Elizabeth Alexandra

    2014-01-01

    Big data is heralded as having the potential to revolutionize health care by making large amounts of data available to support care delivery, population health, and patient engagement. Critics argue that big data's transformative potential is inhibited by privacy requirements that restrict health information exchange. However, there are a variety of permissible activities involving use and disclosure of patient information that support care delivery and management. This article presents an ov...

  19. The role of big laboratories

    International Nuclear Information System (INIS)

    This paper presents the role of big laboratories in their function as research infrastructures. Starting from the general definition and features of big laboratories, the paper goes on to present the key ingredients and issues, based on scientific excellence, for the successful realization of large-scale science projects at such facilities. The paper concludes by taking the example of scientific research in the field of particle physics and describing the structures and methods required to be implemented for the way forward. (paper)

  20. The role of big laboratories

    CERN Document Server

    Heuer, Rolf-Dieter

    2013-01-01

    This paper presents the role of big laboratories in their function as research infrastructures. Starting from the general definition and features of big laboratories, the paper goes on to present the key ingredients and issues, based on scientific excellence, for the successful realization of large-scale science projects at such facilities. The paper concludes by taking the example of scientific research in the field of particle physics and describing the structures and methods required to be implemented for the way forward.

  1. Steering Control of Wheeled Armored Vehicle with Brushless DC Motor

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Considering the steering characters of one type of wheeled armored vehicle, a brushless direct current (DC) motor is adapted as the actuator for steering control. After investigating the known algorithms, one kind of algorithm, which combines the fuzzy logic control with the self-adapting PID control and the startup and pre-brake control, is put forward. Then a test-bed is constructed, and an experiment is conducted. The result of experiment confirms the validity of this algorithm in steering control of wheeled armored vehicle with brushless DC motor.

  2. NSTS Orbiter auxiliary power unit turbine wheel cracking risk assessment

    Science.gov (United States)

    Cruse, T. A.; Mcclung, R. C.; Torng, T. Y.

    1992-01-01

    The present investigation of turbine-wheel cracking problems in the hydrazine-fueled APU turbine wheel of the Space Shuttle Orbiter's Main Engines has indicated the efficacy of systematic probabilistic risk assessment in flight certification and safety resolution. Nevertheless, real crack-initiation and propagation problems do not lend themselves to purely analytical studies. The high-cycle fatigue problem is noted to generally be unsuited to probabilistic modeling, due to its extremely high degree of intrinsic scatter. In the case treated, the cracks appear to trend toward crack arrest in a low cycle fatigue mode, due to a detuning of the resonance model.

  3. Fabrication of micro gear wheels by micropowder injection molding

    Institute of Scientific and Technical Information of China (English)

    Haiqing Yin; Xuanhui Qu; Chengchang Jia

    2008-01-01

    The micropowder injection molding technology was investigated to fabricate the microsized gear wheels on a conventional injection molding machine. The feedstock comprised of carbonyl ferrum powder and a wax-based thermoplastic binder. Microinjection molding was fulfilled at about 423 K under 100 MPa. The heating system was applied to the die to improve the fluidity of the feedstock and subsequently the cooling system was used to enhance the strength of the green compacts after injection by decreasing the temperature of the die. The gear wheels were realized successfully with their addendum circle diameter ranging from 800 to 200 m and with the center hole as small as 60 μtm.

  4. Effect of food toxicants on voluntary wheel running in rats.

    Science.gov (United States)

    Squibb, R E; Squibb, R L

    1979-05-01

    Voluntary wheel running in rats in reaction to a dietary deficiency of iron or food toxicants of natural (dioscin) and environmental (cadmium) origins was used to develop a behavioral model by which rapid detection of food contaminants was accomplished following induction of spontaneous activity by techniques of feed restriction. High levels of voluntary wheel running in reference controls were followed by significant depressions in running activity in animals fed the dietary toxicants. Analyses of blood and liver tissues and depressions of testes size confirmed the presence of the insults to metabolism. PMID:438894

  5. Unusual orbitocranial penetrating injury by a grinding wheel: case report

    Institute of Scientific and Technical Information of China (English)

    Murat Vural; Yakup Karabagli; Hikmet Basmak; Baki Adapinar; Ramazan Durmaz; Metin Ant Atasoy

    2009-01-01

    @@ Orbitocranial penetrating injuries are uncommon and usually life threatening, which constitute about 0.4% of all head injuries, 24% of penetrating head trauma in adults, and 45% in children.1,2,3They may occur accidentally or due to an assault and may have serious consequences and can be potentially fatal.4,5 Immediate plastic and reconstructive surgery, ophthalmology and radiology consultations are essential for the proper diagnosis and treatment. We reported an adult patient with a transorbital cerebral injury by an unusual material---grinding wheel. To our knowledge, this is the first reported case of transorbital penetrating injury by a grinding wheel in the literature.

  6. A Feasability Study of the Wheel Electrostatic Spectrometer

    Science.gov (United States)

    Johansen, Michael Ryan; Phillips, James Ralph; Kelley, Joshua David; Mackey, Paul J.; Holbert, Eirik; Clements, Gregory R.; Calle, Carlos I.

    2014-01-01

    Mars rover missions rely on time-consuming, power-exhausting processes to analyze the Martian regolith. A low power electrostatic sensor in the wheels of a future Mars rover could be used to quickly determine when the rover is driving over a different type of regolith. The Electrostatics and Surface Physics Laboratory at NASA's Kennedy Space Center developed the Wheel Electrostatic Spectrometer as a feasibility study to investigate this option. In this paper, we discuss recent advances in this technology to increase the repeatability of the tribocharging experiments, along with supporting data. In addition, we discuss the development of a static elimination tool optimized for Martian conditions.

  7. INFLUENCE OF WHEEL STRUCTURAL PARAMETERS ON MACHINING ACCURACY OF ULTRA-PRECISION PLANE HONING

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A new idea for designing wheel patterns is presented so as to solve the problems about machining accuracy ofworkpiece and wear of honing wheel in ultra-precision plane honing. The influence factors on motion principle and pat-tern structures are analyzed and optimization machining parameters are obtained. By calculating effective cutting lengthon the surface of workpiece cut by wheel's abrasive and the orbit of one point on the surface of workpiece contactingwith wheel, the wear coefficient of different kinds of wheels and accuracy coefficient of workpiece machined by corre-sponding wheels are obtained. Furthermore, the simulation results show that the optimal pattern structure of wheel turnsout to have lower wheel wear and higher machining accuracy.

  8. PARAMETER MATCHING OF INTERNAL COMBUSTION ENGINE AND ELECTROMECHANICAL POWER TRAIN OF WHEEL TRACTOR

    OpenAIRE

    A. Kliuchnikov

    2014-01-01

    The paper considers stepless electromechanical power train of a wheel tractor. Methodology for parameter matching of electromechanical transmission and internal combustion engine for their optimum performance as part of a power wheel tractor unit. 

  9. PARAMETER MATCHING OF INTERNAL COMBUSTION ENGINE AND ELECTROMECHANICAL POWER TRAIN OF WHEEL TRACTOR

    Directory of Open Access Journals (Sweden)

    A. Kliuchnikov

    2012-01-01

    Full Text Available The paper considers stepless electromechanical power train of a wheel tractor. Methodology for parameter matching of electromechanical transmission and internal combustion engine for their optimum performance as part of a power wheel tractor unit. 

  10. Engineering report. Part 1: NASA wheel air seal development for space shuttle type environmental requirements

    Science.gov (United States)

    1973-01-01

    The sealing techniques are studied for existing aircraft wheel-tire designs to meet the hard vacuum .00001 torr and cold temperature -65 F requirements of space travel. The investigation covers the use of existing wheel seal designs.

  11. Residual Stress in Wheels: Comparison of Neutron Diffraction and Ultrasonic Methods, with Trends in RCF

    OpenAIRE

    Molyneux-Berry, Paul; Bevan, Adam; Zhang, S. Y.; S Kabra

    2014-01-01

    The critical damage mechanism on many GB passenger train wheels is Rolling Contact Fatigue (RCF) cracking in the rim. Evidence from field observations suggests that RCF damage occurs much more quickly as the wheelsets near the end of their life. Wheel manufacturing processes induce a compressive hoop stress in the wheel rim; variations in residual stress through the life of a wheel may influence the observed RCF damage rates. This paper describes experiments to measure residual stresses in...

  12. Steered wheel for the support and/or steering of a vehicle, particularly hovercraft

    Energy Technology Data Exchange (ETDEWEB)

    Duell, H.J.; Kirchner, G.

    1977-04-07

    The invention concerns a steered wheel for the support or steering of a hovercraft, whose wheel suspension is provided with an eccentric journal for automatic setting in the direction of travel. So that the vehicle will not leave its track during changes of direction when the wheel is turned around the eccentric axis, according to the invention the wheel is supported on movable bearings at the journal in the direction of the driving axle.

  13. 14 CFR 29.497 - Ground loading conditions: landing gear with tail wheels.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Ground loading conditions: landing gear... Requirements Ground Loads § 29.497 Ground loading conditions: landing gear with tail wheels. (a) General. Rotorcraft with landing gear with two wheels forward and one wheel aft of the center of gravity must...

  14. 14 CFR 27.497 - Ground loading conditions: landing gear with tail wheels.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Ground loading conditions: landing gear... Requirements Ground Loads § 27.497 Ground loading conditions: landing gear with tail wheels. (a) General. Rotorcraft with landing gear with two wheels forward, and one wheel aft, of the center of gravity must...

  15. 14 CFR 25.499 - Nose-wheel yaw and steering.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Nose-wheel yaw and steering. 25.499 Section... AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure Ground Loads § 25.499 Nose-wheel yaw and... nose wheel ground contact equal to 0.8 of the vertical ground reaction at that point are assumed....

  16. The wagon wheel illusion in movies and reality.

    OpenAIRE

    Purves, D.; Paydarfar, J A; Andrews, T J

    1996-01-01

    Wheels turning in the movies or in other forms of stroboscopic presentation often appear to be rotating backward. Remarkably, a similar illusion is also seen in continuous light. The occurrence of this perception in the absence of intermittent illumination suggests that we normally see motion, as in movies, by processing a series of visual episodes.

  17. Effect of machinery wheel load on grass yield

    DEFF Research Database (Denmark)

    Green, Ole; Jørgensen, Rasmus Nyholm; Kristensen, Kristian;

    2010-01-01

    Effect of machinery wheel load on grass   Ole Green1, Rasmus N. Jørgensen2, Kristian Kristensen3, René Gislum3, Dionysis Bochtis1, & Claus G. Sørensen1   1University of Aarhus, Dept. of Agricultural Engineering 2University of Southern Denmark, Inst. of Chemical Eng., Biotechnology and Environmental...

  18. 49 CFR 229.75 - Wheels and tire defects.

    Science.gov (United States)

    2010-10-01

    ..., DEPARTMENT OF TRANSPORTATION RAILROAD LOCOMOTIVE SAFETY STANDARDS Safety Requirements Suspension System § 229... in width. (c) A broken rim, if the tread, measured from the flange at a point five-eighths inch above... crack or break in the flange, tread, rim, plate, or hub. (l) A loose wheel or tire. (m) Fusion...

  19. 16 CFR 1512.11 - Requirements for wheels.

    Science.gov (United States)

    2010-01-01

    ... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Requirements for wheels. 1512.11 Section 1512.11 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FEDERAL HAZARDOUS SUBSTANCES ACT... lbf) and tested in accordance with the rim test, § 1512.18(j). Sidewalk bicycles need not meet...

  20. Design of wheel-type walking-assist device

    International Nuclear Information System (INIS)

    In this research, a outdoor wheel-type walking-assist device is developed to help an elder having a poor muscular strength at legs for walking, sitting and standing up easily at outdoors, and also for going and downing stairs. In conceptually designing, the environments of an elder's activity, the size of an elder's body and a necessary function of helping an elder are considered. This device has 4 wheels for stability. When an elder walks in incline plane with the proposed device, a rear-wing is rotated to keep the supporting device horizontal, regardless of an angle of inclination. A height-controlling device, which can control the height of the supporting device for adjusting an elder's height, is varied vertically to help an elder to sit and stand-up easily. Moreover, a outdoor wheel-type walking-assist device is conceptually designed and is made. In order to design it, the preview research is investigated firstly. On the basis of the proposed walking-assist device, the outdoor walking-assist device is designed and made. The outdoor wheel-type walking-assist device can go and down stairs automatically. This device go up and down the stair of having maximum 20cm height and an angle of 25 degrees with maximum 4 sec/stairs speed, and move at flatland with 60cm/sec speed

  1. Development of morphology in laser dressed grinding wheels

    Directory of Open Access Journals (Sweden)

    M.J. Jackson

    2007-05-01

    Full Text Available Purpose: The paper describes the development of faceted morphology in laser dressed grinding wheels.Design/methodology/approach: The approach used in the paper is based on locally melting a vitrified grinding wheel and measuring features such as grain size, cooling rate and melt depth as a function of laser fluence and relating these measures to the morphology shown in the microstructures presented in the paper.Findings: The findings of this course of research lead the authors to believe that a specific morphology is dependent upon cooling rate and laser fluence.Research limitations/implications: The findings show that further research is required to fully understand how certain morphologies form as a function of cooling rate and laser fluence. It should be noted that morphologies observed in laser processed grinding wheels include cellular and fully dendritic morphologies in addition to faceted vertices.Practical implications: The results imply that laser dressed grinding wheels can be used for machining different materials at different grinding speeds. The paper also shows that much development is needed to identify laser processing conditions that are appropriate for different workpiece materials.Originality/value: The paper shows that different morphologies can be used to machine workpiece materials under different conditions. The originality in the paper is focused on the formation on minute cutting points using increasing laser fluences.

  2. Estimating Friction Parameters in Reaction Wheels for Attitude Control

    Directory of Open Access Journals (Sweden)

    Valdemir Carrara

    2013-01-01

    Full Text Available The ever-increasing use of artificial satellites in both the study of terrestrial and space phenomena demands a search for increasingly accurate and reliable pointing systems. It is common nowadays to employ reaction wheels for attitude control that provide wide range of torque magnitude, high reliability, and little power consumption. However, the bearing friction causes the response of wheel to be nonlinear, which may compromise the stability and precision of the control system as a whole. This work presents a characterization of a typical reaction wheel of 0.65 Nms maximum angular momentum storage, in order to estimate their friction parameters. It used a friction model that takes into account the Coulomb friction, viscous friction, and static friction, according to the Stribeck formulation. The parameters were estimated by means of a nonlinear batch least squares procedure, from data raised experimentally. The results have shown wide agreement with the experimental data and were also close to a deterministic model, previously obtained for this wheel. This model was then employed in a Dynamic Model Compensator (DMC control, which successfully reduced the attitude steady state error of an instrumented one-axis air-bearing table.

  3. Design of wheel-type walking-assist device

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Seung Ho; Kim, Seung Ho; Kim, Chang Hoi; Seo, Yong Chil; Jung, Kyung Min; Lee, Sung Uk

    2006-03-15

    In this research, a outdoor wheel-type walking-assist device is developed to help an elder having a poor muscular strength at legs for walking, sitting and standing up easily at outdoors, and also for going and downing stairs. In conceptually designing, the environments of an elder's activity, the size of an elder's body and a necessary function of helping an elder are considered. This device has 4 wheels for stability. When an elder walks in incline plane with the proposed device, a rear-wing is rotated to keep the supporting device horizontal, regardless of an angle of inclination. A height-controlling device, which can control the height of the supporting device for adjusting an elder's height, is varied vertically to help an elder to sit and stand-up easily. Moreover, a outdoor wheel-type walking-assist device is conceptually designed and is made. In order to design it, the preview research is investigated firstly. On the basis of the proposed walking-assist device, the outdoor walking-assist device is designed and made. The outdoor wheel-type walking-assist device can go and down stairs automatically. This device go up and down the stair of having maximum 20cm height and an angle of 25 degrees with maximum 4 sec/stairs speed, and move at flatland with 60cm/sec speed.

  4. Assessing the sustainability of water governance systems: the sustainability wheel

    OpenAIRE

    Schneider F.; Bonriposi M.; Graefe O.; Herweg K.; Homewood C.; Huss M.; Kauzlaric M.; Liniger H.; Rey E.; Reynard E. (ed.); Rist S.; Schädler B.; Weingartner R.

    2015-01-01

    We present and test a conceptual and methodological approach for interdisciplinary sustainability assessments of water governance systems based on what we call the sustainability wheel. The approach combines transparent identification of sustainability principles, their regional contextualization through sub-principles (indicators), and the scoring of these indicators through deliberative dialogue within an interdisciplinary team of researchers, taking into account their various qualitative a...

  5. Wheel-rail interaction at short-wave irregularities

    NARCIS (Netherlands)

    Steenbergen, M.J.M.M.

    2008-01-01

    Short-wave irregularities in the wheel-rail interface are at the basis of track and vehicle damage and deterioration. On the short term, they result into high dynamic train-track interaction forces and a high energy input into the system that must be dissipated in the different system components or

  6. A new solution method for wheel/rail rolling contact.

    Science.gov (United States)

    Yang, Jian; Song, Hua; Fu, Lihua; Wang, Meng; Li, Wei

    2016-01-01

    To solve the problem of wheel/rail rolling contact of nonlinear steady-state curving, a three-dimensional transient finite element (FE) model is developed by the explicit software ANSYS/LS-DYNA. To improve the solving speed and efficiency, an explicit-explicit order solution method is put forward based on analysis of the features of implicit and explicit algorithm. The solution method was first applied to calculate the pre-loading of wheel/rail rolling contact with explicit algorithm, and then the results became the initial conditions in solving the dynamic process of wheel/rail rolling contact with explicit algorithm as well. Simultaneously, the common implicit-explicit order solution method is used to solve the FE model. Results show that the explicit-explicit order solution method has faster operation speed and higher efficiency than the implicit-explicit order solution method while the solution accuracy is almost the same. Hence, the explicit-explicit order solution method is more suitable for the wheel/rail rolling contact model with large scale and high nonlinearity. PMID:27217986

  7. Using the Pottery Wheel to Explore Topics in Calculus

    Science.gov (United States)

    Farnell, Elin; Snipes, Marie A.

    2015-01-01

    Students sometimes struggle with visualizing the three-dimensional solids encountered in certain integral problems in a calculus class. We present a project in which students create solids of revolution with clay on a pottery wheel and estimate the volumes of these objects using Riemann sums. In addition to giving students an opportunity for…

  8. A Switching Controller System for a Wheeled Mobile Robot

    Institute of Scientific and Technical Information of China (English)

    Masanori Sato; Atushi Kanda; Kazuo Ishii

    2007-01-01

    A wheeled mobile mechanism with a passive and/or active linkage mechanism for rough terrain environment is developed and evaluated. The wheeled mobile mechanism which has high mobility in rough terrain needs sophisticated system to adapt various environments.We focus on the development of a switching controller system for wheeled mobile robots in rough terrain. This system consists of two sub-systems: an environment recognition system using link angles and an adaptive control system. In the environment recognition system, we introduce a Self-Organizing Map (SOM) for clustering link angles. In the adaptive controllers, we introduce neural networks to calculate the inverse model of the wheeled mobile robot.The environment recognition system can recognize the environment in which the robot travels, and the adjustable controllers are tuned by experimental results for each environment. The dual sub-system switching controller system is experimentally evaluated. The system recognizes its environment and adapts by switching the adjustable controllers. This system demonstrates superior performance to a well-tuned single PID controller.

  9. Stochastic Wheel-Slip Compensation Based Robot Localization and Mapping

    Directory of Open Access Journals (Sweden)

    SIDHARTHAN, R. K.

    2016-05-01

    Full Text Available Wheel slip compensation is vital for building accurate and reliable dead reckoning based robot localization and mapping algorithms. This investigation presents stochastic slip compensation scheme for robot localization and mapping. Main idea of the slip compensation technique is to use wheel-slip data obtained from experiments to model the variations in slip velocity as Gaussian distributions. This leads to a family of models that are switched depending on the input command. To obtain the wheel-slip measurements, experiments are conducted on a wheeled mobile robot and the measurements thus obtained are used to build the Gaussian models. Then the localization and mapping algorithm is tested on an experimental terrain and a new metric called the map spread factor is used to evaluate the ability of the slip compensation technique. Our results clearly indicate that the proposed methodology improves the accuracy by 72.55% for rotation and 66.67% for translation motion as against an uncompensated mapping system. The proposed compensation technique eliminates the need for extro receptive sensors for slip compensation, complex feature extraction and association algorithms. As a result, we obtain a simple slip compensation scheme for localization and mapping.

  10. "Walking" Along a Free Rotating Bicycle Wheel (Round and Round)

    CERN Document Server

    Guemez, Julio

    2016-01-01

    We describe the kinematics, dynamics and also some energetic issues related to the Marta mouse motion when she walks on top of a horizontal bicycle wheel, which is free to rotate like a merry-to-go round, as presented recently by Paul Hewitt in the Figuring Physics section of this magazine.

  11. Curve Squeal of Train Wheels, Part 3: Active Control

    Science.gov (United States)

    HECKL, MARIA A.; HUANG, X. Y.

    2000-01-01

    This paper presents a new method to annul the squeal noise that is produced by trains traversing a curve. The method is a special form of active control, applied to suppress the bending oscillations of a squealing wheel. It is essentially a feedback system with the following components: sensor, narrowband filter, phase-shifter, amplifier and actuator. The control signal driving the actuator has only a single frequency (set at the filter), and that frequency typically corresponds to one of the bending modes of the wheel. Two versions of the feedback system are considered. In the first version, the actuator exerts a control force on the wheel, and in the second version, the actuator imposes a velocity on the rail. A mathematical model is presented and predictions are made for the performance of both versions. The coupling of the different wheel modes by the control system is discussed. A model rig is described which was used for a practical demonstration of this form of active control. Differences from more conventional forms of active control are pointed out.

  12. Determination of quaternary strata diggability with bucket wheel excavators

    Energy Technology Data Exchange (ETDEWEB)

    Ural, S.; Onur, A.H. [Afsin-Elbistan Lignite Establishment (Turkey)

    1994-12-31

    This paper relates the field investigations of the Quaternary strata series diggability with a bucket wheel excavator (BWE), carried out in Afsin-Elbistan Lignite Establishment (AEL). The investigations were intended to determine the Quaternary strata diggability and, in particular, to define the relative difficulty of excavating in-situ and preblasted layers. 3 refs., 11 figs., 3 tabs.

  13. Low cost attitude control system reaction wheel development

    Science.gov (United States)

    Bialke, William

    1991-01-01

    In order to satisfy a growing demand for low cost attitude control systems for small spacecraft, development of a low power and low cost Reaction Wheel Assembly was initiated. The details of the versatile design resulting from this effort are addressed. Tradeoff analyses for each of the major components are included, as well as test data from an engineering prototype of the hardware.

  14. Mechatronics Design of a Mecanum Wheeled Mobile Robot

    OpenAIRE

    Xu, Peter

    2005-01-01

    The motor driver circuit board designed for the drive of the Mecanum wheels met all the specifications given in Section 3. The limitation to its current handling capacity was the relays which are rated at five amps. The board has provided a cheap and compact 72

  15. Characterizing the Performance of the Wheel Electrostatic Spectrometer

    Science.gov (United States)

    Johansen, Michael R.; Mackey, P. J.; Holbert, E.; Calle, C. I.; Clements, J. S.

    2013-01-01

    Insulators need to be discharged after each wheel revolution. Sensor responses repeatable within one standard deviation in the noise of the signal. Insulators may not need to be cleaned after each revolution. Parent Technology- Mars Environmental Compatibility Assessment/Electrometer Electrostatic sensors with dissimilar cover insulators Protruding insulators tribocharge against regolith simulant Developed for use on the scoop for the 2001 Mars Odyssey lander Wheel Electrostatic Spectrometer Embedded electrostatic sensors in prototype Martian rover wheel If successful, this technology will enable constant electrostatic testing on Mars Air ionizing fan used to neutralize the surface charge on cover insulators . WES rolled on JSClA lunar simulant Control experiment -Static elimination not conducted between trials -Capacitor discharged after each experiment Charge neutralization experiment -Static elimination conducted between trials -Capacitor discharged after each experiment. Air ionizing fan used on insulators after each wheel revolution Capacitor discharged after each trial Care was taken to roll WES with same speed/pressure Error bars represent one standard deviation in the noise of e ach sensor

  16. Big data for bipolar disorder.

    Science.gov (United States)

    Monteith, Scott; Glenn, Tasha; Geddes, John; Whybrow, Peter C; Bauer, Michael

    2016-12-01

    The delivery of psychiatric care is changing with a new emphasis on integrated care, preventative measures, population health, and the biological basis of disease. Fundamental to this transformation are big data and advances in the ability to analyze these data. The impact of big data on the routine treatment of bipolar disorder today and in the near future is discussed, with examples that relate to health policy, the discovery of new associations, and the study of rare events. The primary sources of big data today are electronic medical records (EMR), claims, and registry data from providers and payers. In the near future, data created by patients from active monitoring, passive monitoring of Internet and smartphone activities, and from sensors may be integrated with the EMR. Diverse data sources from outside of medicine, such as government financial data, will be linked for research. Over the long term, genetic and imaging data will be integrated with the EMR, and there will be more emphasis on predictive models. Many technical challenges remain when analyzing big data that relates to size, heterogeneity, complexity, and unstructured text data in the EMR. Human judgement and subject matter expertise are critical parts of big data analysis, and the active participation of psychiatrists is needed throughout the analytical process. PMID:27068058

  17. [Big data in official statistics].

    Science.gov (United States)

    Zwick, Markus

    2015-08-01

    The concept of "big data" stands to change the face of official statistics over the coming years, having an impact on almost all aspects of data production. The tasks of future statisticians will not necessarily be to produce new data, but rather to identify and make use of existing data to adequately describe social and economic phenomena. Until big data can be used correctly in official statistics, a lot of questions need to be answered and problems solved: the quality of data, data protection, privacy, and the sustainable availability are some of the more pressing issues to be addressed. The essential skills of official statisticians will undoubtedly change, and this implies a number of challenges to be faced by statistical education systems, in universities, and inside the statistical offices. The national statistical offices of the European Union have concluded a concrete strategy for exploring the possibilities of big data for official statistics, by means of the Big Data Roadmap and Action Plan 1.0. This is an important first step and will have a significant influence on implementing the concept of big data inside the statistical offices of Germany. PMID:26077871

  18. Dual of Big-bang and Big-crunch

    OpenAIRE

    Bak, Dongsu

    2006-01-01

    Starting from the Janus solution and its gauge theory dual, we obtain the dual gauge theory description of the cosmological solution by procedure of the double anaytic continuation. The coupling is driven either to zero or to infinity at the big-bang and big-crunch singularities, which are shown to be related by the S-duality symmetry. In the dual Yang-Mills theory description, these are non singular at all as the coupling goes to zero in the N=4 Super Yang-Mills theory. The cosmological sing...

  19. Turning big bang into big bounce: II. Quantum dynamics

    International Nuclear Information System (INIS)

    We analyze the big bounce transition of the quantum Friedmann-Robertson-Walker model in the setting of the nonstandard loop quantum cosmology (LQC). Elementary observables are used to quantize composite observables. The spectrum of the energy density operator is bounded and continuous. The spectrum of the volume operator is bounded from below and discrete. It has equally distant levels defining a quantum of the volume. The discreteness may imply a foamy structure of spacetime at a semiclassical level which may be detected in astro-cosmo observations. The nonstandard LQC method has a free parameter that should be fixed in some way to specify the big bounce transition.

  20. Wheel-running activity and energy metabolism in relation to ambient temperature in mice selected for high wheel-running activity

    OpenAIRE

    Vaanholt, Lobke M.; Garland, Theodore; Daan, Serge; Visser, G. Henk; Garland Jr., Theodore; Heldmaier, G

    2007-01-01

    Interrelationships between ambient temperature, activity, and energy metabolism were explored in mice that had been selectively bred for high spontaneous wheel-running activity and their random-bred controls. Animals were exposed to three different ambient temperatures (10, 20 and 30 degrees C) and wheel-running activity and metabolic rate were measured simultaneously. Wheel-running activity was decreased at low ambient temperatures in all animals and was increased in selected animals compare...

  1. Creep feed grinding of a nickel base superalloy with a segmented wheel containing coated CBN

    Energy Technology Data Exchange (ETDEWEB)

    Xu, X.P.; Huang, H. [Huaqiao Univ., Quanzhou (China). Dept. of Mechanical Engineering; Xu, H.J. [Nanjing Univ. of Aeronautics and Astronautics, JS (China)

    2001-07-01

    An investigation is reported of the creep feed grinding of a cast superalloy with segmented CBN wheels. The temperature at the wheel-workpiece interface was measured using a workpiece-wire thermocouple and the forces were detected using a dynamometer. Coupled with previous studies on thermal behavior of intermittent grinding and material removal mechanisms for creep feed grinding of the superalloy using either Al{sub 2}O{sub 3} wheels or continuous CBN wheels, a segmented CNB wheel was introduced to cost-effectively machining of the superalloy by incorporating coated CBN abrasives into the resin bonded segments. (orig.)

  2. Innovative grinding wheel design for cost-effective machining of advanced ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Licht, R.H.; Kuo, P.; Liu, S.; Murphy, D.; Picone, J.W.; Ramanath, S.

    2000-05-01

    This Final Report covers the Phase II Innovative Grinding Wheel (IGW) program in which Norton Company successfully developed a novel grinding wheel for cost-effective cylindrical grinding of advanced ceramics. In 1995, Norton Company successfully completed the 16-month Phase I technical effort to define requirements, design, develop, and evaluate a next-generation grinding wheel for cost-effective cylindrical grinding of advanced ceramics using small prototype wheels. The Phase II program was initiated to scale-up the new superabrasive wheel specification to larger diameters, 305-mm to 406-mm, required for most production grinding of cylindrical ceramic parts, and to perform in-house and independent validation grinding tests.

  3. Casting defects in low-pressure die-cast aluminum alloy wheels

    Science.gov (United States)

    Zhang, B.; Cockcroft, S. L.; Maijer, D. M.; Zhu, J. D.; Phillion, A. B.

    2005-11-01

    Defects in automotive aluminum alloy casting continue to challenge metallurgists and production engineers as greater emphasis is placed on product quality and production cost. A range of casting-related defects found in low-pressure die-cast aluminum wheels were examined metallographically in samples taken from several industrial wheel-casting facilities. The defects examined include macro- and micro- porosity, entrained oxide films, and exogenous oxide inclusions. Particular emphasis is placed on the impact of these defects with respect to the three main casting-related criteria by which automotive wheel quality are judged: wheel cosmetics, air-tightness, and wheel mechanical performance.

  4. CLOUD COMPUTING WITH BIG DATA: A REVIEW

    OpenAIRE

    Anjali; Er. Amandeep Kaur; Mrs. Shakshi

    2016-01-01

    Big data is a collection of huge quantities of data. Big data is the process of examining large amounts of data. Big data and Cloud computing are the hot issues in Information Technology. Big data is the one of the main problem now a day’s. Researchers focusing how to handle huge amount of data with cloud computing and how to gain a perfect security for big data in cloud computing. To handle the Big Data problem Hadoop framework is used in which data is fragmented and executed parallel....

  5. Big Data Analytics in Healthcare

    Directory of Open Access Journals (Sweden)

    Ashwin Belle

    2015-01-01

    Full Text Available The rapidly expanding field of big data analytics has started to play a pivotal role in the evolution of healthcare practices and research. It has provided tools to accumulate, manage, analyze, and assimilate large volumes of disparate, structured, and unstructured data produced by current healthcare systems. Big data analytics has been recently applied towards aiding the process of care delivery and disease exploration. However, the adoption rate and research development in this space is still hindered by some fundamental problems inherent within the big data paradigm. In this paper, we discuss some of these major challenges with a focus on three upcoming and promising areas of medical research: image, signal, and genomics based analytics. Recent research which targets utilization of large volumes of medical data while combining multimodal data from disparate sources is discussed. Potential areas of research within this field which have the ability to provide meaningful impact on healthcare delivery are also examined.

  6. Big Data Analytics in Healthcare.

    Science.gov (United States)

    Belle, Ashwin; Thiagarajan, Raghuram; Soroushmehr, S M Reza; Navidi, Fatemeh; Beard, Daniel A; Najarian, Kayvan

    2015-01-01

    The rapidly expanding field of big data analytics has started to play a pivotal role in the evolution of healthcare practices and research. It has provided tools to accumulate, manage, analyze, and assimilate large volumes of disparate, structured, and unstructured data produced by current healthcare systems. Big data analytics has been recently applied towards aiding the process of care delivery and disease exploration. However, the adoption rate and research development in this space is still hindered by some fundamental problems inherent within the big data paradigm. In this paper, we discuss some of these major challenges with a focus on three upcoming and promising areas of medical research: image, signal, and genomics based analytics. Recent research which targets utilization of large volumes of medical data while combining multimodal data from disparate sources is discussed. Potential areas of research within this field which have the ability to provide meaningful impact on healthcare delivery are also examined. PMID:26229957

  7. Big Data: Astronomical or Genomical?

    Science.gov (United States)

    Stephens, Zachary D; Lee, Skylar Y; Faghri, Faraz; Campbell, Roy H; Zhai, Chengxiang; Efron, Miles J; Iyer, Ravishankar; Schatz, Michael C; Sinha, Saurabh; Robinson, Gene E

    2015-07-01

    Genomics is a Big Data science and is going to get much bigger, very soon, but it is not known whether the needs of genomics will exceed other Big Data domains. Projecting to the year 2025, we compared genomics with three other major generators of Big Data: astronomy, YouTube, and Twitter. Our estimates show that genomics is a "four-headed beast"--it is either on par with or the most demanding of the domains analyzed here in terms of data acquisition, storage, distribution, and analysis. We discuss aspects of new technologies that will need to be developed to rise up and meet the computational challenges that genomics poses for the near future. Now is the time for concerted, community-wide planning for the "genomical" challenges of the next decade. PMID:26151137

  8. Big Data: Astronomical or Genomical?

    Directory of Open Access Journals (Sweden)

    Zachary D Stephens

    2015-07-01

    Full Text Available Genomics is a Big Data science and is going to get much bigger, very soon, but it is not known whether the needs of genomics will exceed other Big Data domains. Projecting to the year 2025, we compared genomics with three other major generators of Big Data: astronomy, YouTube, and Twitter. Our estimates show that genomics is a "four-headed beast"--it is either on par with or the most demanding of the domains analyzed here in terms of data acquisition, storage, distribution, and analysis. We discuss aspects of new technologies that will need to be developed to rise up and meet the computational challenges that genomics poses for the near future. Now is the time for concerted, community-wide planning for the "genomical" challenges of the next decade.

  9. A method for improved accuracy in three dimensions for determining wheel/rail contact points

    Science.gov (United States)

    Yang, Xinwen; Gu, Shaojie; Zhou, Shunhua; Zhou, Yu; Lian, Songliang

    2015-11-01

    Searching for the contact points between wheels and rails is important because these points represent the points of exerted contact forces. In order to obtain an accurate contact point and an in-depth description of the wheel/rail contact behaviours on a curved track or in a turnout, a method with improved accuracy in three dimensions is proposed to determine the contact points and the contact patches between the wheel and the rail when considering the effect of the yaw angle and the roll angle on the motion of the wheel set. The proposed method, with no need of the curve fitting of the wheel and rail profiles, can accurately, directly, and comprehensively determine the contact interface distances between the wheel and the rail. The range iteration algorithm is used to improve the computation efficiency and reduce the calculation required. The present computation method is applied for the analysis of the contact of rails of CHINA (CHN) 75 kg/m and wheel sets of wearing type tread of China's freight cars. In addition, it can be proved that the results of the proposed method are consistent with that of Kalker's program CONTACT, and the maximum deviation from the wheel/rail contact patch area of this two methods is approximately 5%. The proposed method, can also be used to investigate static wheel/rail contact. Some wheel/rail contact points and contact patch distributions are discussed and assessed, wheel and rail non-worn and worn profiles included.

  10. Big Book of Windows Hacks

    CERN Document Server

    Gralla, Preston

    2008-01-01

    Bigger, better, and broader in scope, the Big Book of Windows Hacks gives you everything you need to get the most out of your Windows Vista or XP system, including its related applications and the hardware it runs on or connects to. Whether you want to tweak Vista's Aero interface, build customized sidebar gadgets and run them from a USB key, or hack the "unhackable" screensavers, you'll find quick and ingenious ways to bend these recalcitrant operating systems to your will. The Big Book of Windows Hacks focuses on Vista, the new bad boy on Microsoft's block, with hacks and workarounds that

  11. Sosiaalinen asiakassuhdejohtaminen ja big data

    OpenAIRE

    Toivonen, Topi-Antti

    2015-01-01

    Tässä tutkielmassa käsitellään sosiaalista asiakassuhdejohtamista sekä hyötyjä, joita siihen voidaan saada big datan avulla. Sosiaalinen asiakassuhdejohtaminen on terminä uusi ja monille tuntematon. Tutkimusta motivoi aiheen vähäinen tutkimus, suomenkielisen tutkimuksen puuttuminen kokonaan sekä sosiaalisen asiakassuhdejohtamisen mahdollinen olennainen rooli yritysten toiminnassa tulevaisuudessa. Big dataa käsittelevissä tutkimuksissa keskitytään monesti sen tekniseen puoleen, eikä sovellutuk...

  12. AAPOR Report on Big Data

    OpenAIRE

    Task Force Members Include: Lilli Japec; Frauke Kreuter; Marcus Berg; Paul Biemer; Paul Decker; Cliff Lampe; Julia Lane; Cathy O'Neil; Abe Usher

    2015-01-01

    In recent years we have seen an increase in the amount of statistics in society describing different phenomena based on so called Big Data. The term Big Data is used for a variety of data as explained in the report, many of them characterized not just by their large volume, but also by their variety and velocity, the organic way in which they are created, and the new types of processes needed to analyze them and make inference from them. The change in the nature of the new types of data, thei...

  13. Towards a big crunch dual

    Energy Technology Data Exchange (ETDEWEB)

    Hertog, Thomas E-mail: hertog@vulcan2.physics.ucsb.edu; Horowitz, Gary T

    2004-07-01

    We show there exist smooth asymptotically anti-de Sitter initial data which evolve to a big crunch singularity in a low energy supergravity limit of string theory. This opens up the possibility of using the dual conformal field theory to obtain a fully quantum description of the cosmological singularity. A preliminary study of this dual theory suggests that the big crunch is an endpoint of evolution even in the full string theory. We also show that any theory with scalar solitons must have negative energy solutions. The results presented here clarify our earlier work on cosmic censorship violation in N=8 supergravity. (author)

  14. [Big Data- challenges and risks].

    Science.gov (United States)

    Krauß, Manuela; Tóth, Tamás; Hanika, Heinrich; Kozlovszky, Miklós; Dinya, Elek

    2015-12-01

    The term "Big Data" is commonly used to describe the growing mass of information being created recently. New conclusions can be drawn and new services can be developed by the connection, processing and analysis of these information. This affects all aspects of life, including health and medicine. The authors review the application areas of Big Data, and present examples from health and other areas. However, there are several preconditions of the effective use of the opportunities: proper infrastructure, well defined regulatory environment with particular emphasis on data protection and privacy. These issues and the current actions for solution are also presented. PMID:26614539

  15. The BigBOSS Experiment

    OpenAIRE

    Schlegel, D.; Abdalla, F.; Abraham, T.; Ahn, C.; Prieto, C. Allende; Annis, J.; Aubourg, E.; Azzaro, M.; Baltay, S. Bailey. C.; Baugh, C.; Bebek, C.; Becerril, S.; Blanton, M.; Bolton, A.; Bromley, B.

    2011-01-01

    BigBOSS is a Stage IV ground-based dark energy experiment to study baryon acoustic oscillations (BAO) and the growth of structure with a wide-area galaxy and quasar redshift survey over 14,000 square degrees. It has been conditionally accepted by NOAO in response to a call for major new instrumentation and a high-impact science program for the 4-m Mayall telescope at Kitt Peak. The BigBOSS instrument is a robotically-actuated, fiber-fed spectrograph capable of taking 5000 simultaneous spectra...

  16. Release plan for Big Pete

    International Nuclear Information System (INIS)

    This release plan is to provide instructions for the Radiological Control Technician (RCT) to conduct surveys for the unconditional release of ''Big Pete,'' which was used in the removal of ''Spacers'' from the N-Reactor. Prior to performing surveys on the rear end portion of ''Big Pete,'' it shall be cleaned (i.e., free of oil, grease, caked soil, heavy dust). If no contamination is found, the vehicle may be released with the permission of the area RCT Supervisor. If contamination is found by any of the surveys, contact the cognizant Radiological Engineer for decontamination instructions

  17. Method for the multi-criteria optimization of car wheel suspension mechanisms

    Directory of Open Access Journals (Sweden)

    Catalin Alexandru

    2016-08-01

    Full Text Available The paper deals with a general method for the multi-criteria optimization of the rear wheels suspension mechanisms in terms of kinematic behavior. The suspension mechanism is decomposed in basic binary links, and the kinematic synthesis is separately performed for each of them. The design variables are the global coordinates of the joint locations on the car body (chassis. The disposing of the joints on the wheel carrier were exclusively established by constructive criteria. The design objectives relate to kinematic position parameters of the wheel (displacements of the wheel centre along longitudinal and transversal directions, and modifications of the wheel axis direction, the optimization goal being to minimize these variations during the wheel travel. A computer program for the kinematic study was developed in C++. The application was performed for the wheel suspension mechanism of a race car.

  18. Study on general theory of kinematics and dynamics of wheeled mobile robots

    Science.gov (United States)

    Tsukishima, Takahiro; Sasaki, Ken; Takano, Masaharu; Inoue, Kenji

    1992-03-01

    This paper proposes a general theory of kinematics and dynamics of wheeled mobile robots (WMRs). Unlike robotic manipulators which are modeled as 3-dimensional serial link mechanism, WMRs will be modeled as planar linkage mechanism with multiple links branching out from the base and/or another link. Since this model resembles a tree with branches, it will be called 'tree-structured-link'. The end of each link corresponds to the wheel which is in contact with the floor. In dynamics of WMR, equation of motion of a WMR is derived from joint input torques incorporating wheel dynamics. The wheel dynamics determines forces and moments acting on wheels as a function of slip velocity. This slippage of wheels is essential in dynamics of WMR. It will also be shown that the dynamics of WMR reduces to kinematics when slippage of wheels is neglected. Furthermore, the equation of dynamics is rewritten in velocity input form, since most of industrial motors are velocity controlled.

  19. Big society, big data. The radicalisation of the network society

    NARCIS (Netherlands)

    Frissen, V.

    2011-01-01

    During the British election campaign of 2010, David Cameron produced the idea of the ‘Big Society’ as a cornerstone of his political agenda. At the core of the idea is a stronger civil society and local community coupled with a more withdrawn government. Although many commentators have dismissed thi

  20. New Vitrified Bond Diamond Grinding Wheel for Grinding the Cylinder of Polycrystalline Diamond Compacts

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    In this work, a kind of new vitrified bond based on Li2O-Al2O3-SiO2 glass ceramics was used to bond the diamond grains, which is made into grinding wheel and the cylindrical grinding process of polycrystalline diamond compacts (PDCs) by using the new vitrified bond diamond grinding wheel was discussed. Several factors which influence the properties of grinding wheel such as amount of vitrified bond and the kinds and amount of stuff in grinding wheel were also investigated. It was found that the new vitrified bond can firmly combine diamond grains, when there are only diamonds and vitrified bond in the structure of grinding wheel, the longevity of the grinding wheel is about 2.5-3 times as that of resin bond grinding wheel for processing PDCs. The grinding size precision of PDCs can be improved from ±0.03 mm to ±0.01 mm because of larger Young's modulus of vitrified bond than resin bond. The grinding time of a PDC product can be 1.75-2.0 min from 3.25-3.5 min, so this kind of grinding wheel can save much time for processing PDCs. Also, there is hardly noise when using this new vitrified bond diamond grinding wheel to process PDCs. The amount of vitrified bond in grinding wheel influences the longevity of grinding wheel. When the size of diamond grains is 90-107 μm, the optimal amount of vitrified bond in grinding wheel is 21% (wt pet). When the amount of vitrified bond exceeds 21%, there are many pores in grinding block, which will decrease the longevity of grinding wheel. The existence of addition stuff such as Al2O3 or SiC can reduce the longevity of grinding wheel.

  1. Innovative grinding wheel design for cost-effective machining of advanced ceramics. Phase I, final report

    Energy Technology Data Exchange (ETDEWEB)

    Licht, R.H.; Ramanath, S.; Simpson, M.; Lilley, E.

    1996-02-01

    Norton Company successfully completed the 16-month Phase I technical effort to define requirements, design, develop, and evaluate a next-generation grinding wheel for cost-effective cylindrical grinding of advanced ceramics. This program was a cooperative effort involving three Norton groups representing a superabrasive grinding wheel manufacturer, a diamond film manufacturing division and a ceramic research center. The program was divided into two technical tasks, Task 1, Analysis of Required Grinding Wheel Characteristics, and Task 2, Design and Prototype Development. In Task 1 we performed a parallel path approach with Superabrasive metal-bond development and the higher technical risk, CVD diamond wheel development. For the Superabrasive approach, Task 1 included bond wear and strength tests to engineer bond-wear characteristics. This task culminated in a small-wheel screening test plunge grinding sialon disks. In Task 2, an improved Superabrasive metal-bond specification for low-cost machining of ceramics in external cylindrical grinding mode was identified. The experimental wheel successfully ground three types of advanced ceramics without the need for wheel dressing. The spindle power consumed by this wheel during test grinding of NC-520 sialon is as much as to 30% lower compared to a standard resin bonded wheel with 100 diamond concentration. The wheel wear with this improved metal bond was an order of magnitude lower than the resin-bonded wheel, which would significantly reduce ceramic grinding costs through fewer wheel changes for retruing and replacements. Evaluation of ceramic specimens from both Tasks 1 and 2 tests for all three ceramic materials did not show evidence of unusual grinding damage. The novel CVD-diamond-wheel approach was incorporated in this program as part of Task 1. The important factors affecting the grinding performance of diamond wheels made by CVD coating preforms were determined.

  2. To the question of modeling of wheels and rails wear processes

    Directory of Open Access Journals (Sweden)

    S.V. Myamlin

    2013-06-01

    Full Text Available Purpose. There is a need of wear process modeling in the wheel-rail system. This is related to the fact that the wear processes in this system are absolutely different in the initial and final stages. The profile change of rail and, especially, of the wheels caused by the wear significantly affects the rolling stock dynamics, traffic safety and the resource of the wheels and rails. Wear modeling and the traffic safety evaluation requires the accounting of the low frequency component forces (including the modeling of transitional areas affecting the wheel on the side of the rail and carriage in motion of rolling stock, so the statistical analysis is not possible. Methodology. The method of mathematical modeling of the wheel set and the rail interaction was used during the research conducting. Findings. As a result of the modeling of the wheel set motion on the rail track, the mathematic model with 19 freedom degrees was obtained. This model takes into account the axle torque and studies wheels constructions as the components of the mechanical systems, consisting of a hub and tire. Originality. The mathematic model allows evaluating the wear degree of the wheels and rails when using on the rolling stock not only all-metal wheel sets, but also compound ones with the use of spring wheels and independent rotation of semi-axes with the wheels. Practical value. The development of the improved mathematical model of freight car wheel set motion with differential rotation of the wheels and compound axles allows studying the wear processes of wheels and rails.

  3. Vorticity amplification near the stagnation point of landing gear wheels

    Science.gov (United States)

    Feltham, G.; Ekmekci, A.

    2014-04-01

    The vicinity near the forward stagnation point of landing-gear wheels has been found to support a mechanism for oncoming streams of weak vorticity to collect, grow, and amplify into discrete large-scale vortical structures that then shed with a distinct periodicity. To the authors' knowledge, such a flow phenomenon has never been reported before for landing gear wheels, which are in essence finite (three-dimensional) cylinders. To gain further insight into this phenomenon, a detailed experimental study has been undertaken employing the hydrogen bubble visualization and Particle Image Velocimetry techniques. A very thin platinum wire, similar to those used in hydrogen bubble visualization applications, was placed upstream of the wheel model to produce two streams of weak vorticity (with opposite sign) that convected toward the model. As the vorticity streams enter the stagnation region of the wheels, significant flow deceleration and vorticity stretching act to collect, grow, and amplify the incoming vorticity streams into large-scale vortical structures. Experiments were performed at a fixed Reynolds number, with a value of 32 500 when defined based on the diameter of the wheel and a value of 21 based on the diameter of the vorticity-generating upstream wire. First, to establish a baseline, the natural flow field (without the presence of an upstream wire) was characterized, where experimentally determined values for the stagnation boundary-layer thickness and the velocity profile along the stagnation streamline were both found to agree with the values provided in the literature for two-dimensional cylinders. Subsequently, the dynamics of vorticity collection, growth, amplification, and shedding were studied. The size, stand-off distance and the shedding frequency of the vortical structures forming near the stagnation region were all found to strongly depend on the impingement location of the inbound vorticity on the wheel. A simple relationship between the non

  4. Do Big Bottles Kickstart Infant Weight Issues?

    Science.gov (United States)

    ... nih.gov/medlineplus/news/fullstory_159241.html Do Big Bottles Kickstart Infant Weight Issues? Smaller baby bottles ... 2016 (HealthDay News) -- Feeding babies formula from a big bottle might put them at higher risk for ...

  5. Big data e data science

    OpenAIRE

    Cavique, Luís

    2014-01-01

    Neste artigo foram apresentados os conceitos básicos de Big Data e a nova área a que deu origem, a Data Science. Em Data Science foi discutida e exemplificada a noção de redução da dimensionalidade dos dados.

  6. Do big gods cause anything?

    DEFF Research Database (Denmark)

    Geertz, Armin W.

    2014-01-01

    Dette er et bidrag til et review symposium vedrørende Ara Norenzayans bog Big Gods: How Religion Transformed Cooperation and Conflict (Princeton University Press 2013). Bogen er spændende men problematisk i forhold til kausalitet, ateisme og stereotyper om jægere-samlere....

  7. China: Big Changes Coming Soon

    Science.gov (United States)

    Rowen, Henry S.

    2011-01-01

    Big changes are ahead for China, probably abrupt ones. The economy has grown so rapidly for many years, over 30 years at an average of nine percent a year, that its size makes it a major player in trade and finance and increasingly in political and military matters. This growth is not only of great importance internationally, it is already having…

  8. YOUNG CITY,BIG PARTY

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Shenzhen Universiade unites the world’s young people through sports with none of the usual hoop-la, no fireworks, no grand performances by celebrities and superstars, the Shenzhen Summer Universiade lowered the curtain on a big party for youth and college students on August 23.

  9. BIG DATA IN BUSINESS ENVIRONMENT

    Directory of Open Access Journals (Sweden)

    Logica BANICA

    2015-06-01

    Full Text Available In recent years, dealing with a lot of data originating from social media sites and mobile communications among data from business environments and institutions, lead to the definition of a new concept, known as Big Data. The economic impact of the sheer amount of data produced in a last two years has increased rapidly. It is necessary to aggregate all types of data (structured and unstructured in order to improve current transactions, to develop new business models, to provide a real image of the supply and demand and thereby, generate market advantages. So, the companies that turn to Big Data have a competitive advantage over other firms. Looking from the perspective of IT organizations, they must accommodate the storage and processing Big Data, and provide analysis tools that are easily integrated into business processes. This paper aims to discuss aspects regarding the Big Data concept, the principles to build, organize and analyse huge datasets in the business environment, offering a three-layer architecture, based on actual software solutions. Also, the article refers to the graphical tools for exploring and representing unstructured data, Gephi and NodeXL.

  10. Characterizing and Subsetting Big Data Workloads

    OpenAIRE

    Jia, Zhen; Zhan, Jianfeng; Wang, Lei; Han, Rui; Mckee, Sally A.; Yang, Qiang; Luo, Chunjie; Li, Jingwei

    2014-01-01

    Big data benchmark suites must include a diversity of data and workloads to be useful in fairly evaluating big data systems and architectures. However, using truly comprehensive benchmarks poses great challenges for the architecture community. First, we need to thoroughly understand the behaviors of a variety of workloads. Second, our usual simulation-based research methods become prohibitively expensive for big data. As big data is an emerging field, more and more software stacks are being p...

  11. Big Graph Mining: Frameworks and Techniques

    OpenAIRE

    Aridhi, Sabeur; Nguifo, Engelbert Mephu

    2016-01-01

    Big graph mining is an important research area and it has attracted considerable attention. It allows to process, analyze, and extract meaningful information from large amounts of graph data. Big graph mining has been highly motivated not only by the tremendously increasing size of graphs but also by its huge number of applications. Such applications include bioinformatics, chemoinformatics and social networks. One of the most challenging tasks in big graph mining is pattern mining in big gra...

  12. The BigBoss Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Schelgel, D.; Abdalla, F.; Abraham, T.; Ahn, C.; Allende Prieto, C.; Annis, J.; Aubourg, E.; Azzaro, M.; Bailey, S.; Baltay, C.; Baugh, C.; Bebek, C.; Becerril, S.; Blanton, M.; Bolton, A.; Bromley, B.; Cahn, R.; Carton, P.-H.; Cervanted-Cota, J.L.; Chu, Y.; Cortes, M.; /APC, Paris /Brookhaven /IRFU, Saclay /Marseille, CPPM /Marseille, CPT /Durham U. / /IEU, Seoul /Fermilab /IAA, Granada /IAC, La Laguna / /IAC, Mexico / / /Madrid, IFT /Marseille, Lab. Astrophys. / / /New York U. /Valencia U.

    2012-06-07

    BigBOSS is a Stage IV ground-based dark energy experiment to study baryon acoustic oscillations (BAO) and the growth of structure with a wide-area galaxy and quasar redshift survey over 14,000 square degrees. It has been conditionally accepted by NOAO in response to a call for major new instrumentation and a high-impact science program for the 4-m Mayall telescope at Kitt Peak. The BigBOSS instrument is a robotically-actuated, fiber-fed spectrograph capable of taking 5000 simultaneous spectra over a wavelength range from 340 nm to 1060 nm, with a resolution R = {lambda}/{Delta}{lambda} = 3000-4800. Using data from imaging surveys that are already underway, spectroscopic targets are selected that trace the underlying dark matter distribution. In particular, targets include luminous red galaxies (LRGs) up to z = 1.0, extending the BOSS LRG survey in both redshift and survey area. To probe the universe out to even higher redshift, BigBOSS will target bright [OII] emission line galaxies (ELGs) up to z = 1.7. In total, 20 million galaxy redshifts are obtained to measure the BAO feature, trace the matter power spectrum at smaller scales, and detect redshift space distortions. BigBOSS will provide additional constraints on early dark energy and on the curvature of the universe by measuring the Ly-alpha forest in the spectra of over 600,000 2.2 < z < 3.5 quasars. BigBOSS galaxy BAO measurements combined with an analysis of the broadband power, including the Ly-alpha forest in BigBOSS quasar spectra, achieves a FOM of 395 with Planck plus Stage III priors. This FOM is based on conservative assumptions for the analysis of broad band power (k{sub max} = 0.15), and could grow to over 600 if current work allows us to push the analysis to higher wave numbers (k{sub max} = 0.3). BigBOSS will also place constraints on theories of modified gravity and inflation, and will measure the sum of neutrino masses to 0.024 eV accuracy.

  13. The use of a running wheel to measure activity in rodents: Relationship to energy balance, general activity, and reward

    OpenAIRE

    Novak, Colleen M.; Burghardt, Paul R.; Levine, James A.

    2012-01-01

    Running wheels are commonly employed to measure rodent physical activity in a variety of contexts, including studies of energy balance and obesity. There is no consensus on the nature of wheel-running activity or its underlying causes, however. Here, we will begin by systematically reviewing how running wheel availability affects physical activity and other aspects of energy balance in laboratory rodents. While wheel running and physical activity in the absence of a wheel commonly correlate i...

  14. Judging Big Deals: Challenges, Outcomes, and Advice

    Science.gov (United States)

    Glasser, Sarah

    2013-01-01

    This article reports the results of an analysis of five Big Deal electronic journal packages to which Hofstra University's Axinn Library subscribes. COUNTER usage reports were used to judge the value of each Big Deal. Limitations of usage statistics are also discussed. In the end, the author concludes that four of the five Big Deals are good…

  15. A SWOT Analysis of Big Data

    Science.gov (United States)

    Ahmadi, Mohammad; Dileepan, Parthasarati; Wheatley, Kathleen K.

    2016-01-01

    This is the decade of data analytics and big data, but not everyone agrees with the definition of big data. Some researchers see it as the future of data analysis, while others consider it as hype and foresee its demise in the near future. No matter how it is defined, big data for the time being is having its glory moment. The most important…

  16. Big Data: Implications for Health System Pharmacy.

    Science.gov (United States)

    Stokes, Laura B; Rogers, Joseph W; Hertig, John B; Weber, Robert J

    2016-07-01

    Big Data refers to datasets that are so large and complex that traditional methods and hardware for collecting, sharing, and analyzing them are not possible. Big Data that is accurate leads to more confident decision making, improved operational efficiency, and reduced costs. The rapid growth of health care information results in Big Data around health services, treatments, and outcomes, and Big Data can be used to analyze the benefit of health system pharmacy services. The goal of this article is to provide a perspective on how Big Data can be applied to health system pharmacy. It will define Big Data, describe the impact of Big Data on population health, review specific implications of Big Data in health system pharmacy, and describe an approach for pharmacy leaders to effectively use Big Data. A few strategies involved in managing Big Data in health system pharmacy include identifying potential opportunities for Big Data, prioritizing those opportunities, protecting privacy concerns, promoting data transparency, and communicating outcomes. As health care information expands in its content and becomes more integrated, Big Data can enhance the development of patient-centered pharmacy services. PMID:27559194

  17. "Big Data" - Grosse Daten, viel Wissen?

    OpenAIRE

    Hothorn, Torsten

    2015-01-01

    Since a couple of years, the term Big Data describes technologies to extract knowledge from data. Applications of Big Data and their consequences are also increasingly discussed in the mass media. Because medicine is an empirical science, we discuss the meaning of Big Data and its potential for future medical research.

  18. The BigBoss Experiment

    International Nuclear Information System (INIS)

    BigBOSS is a Stage IV ground-based dark energy experiment to study baryon acoustic oscillations (BAO) and the growth of structure with a wide-area galaxy and quasar redshift survey over 14,000 square degrees. It has been conditionally accepted by NOAO in response to a call for major new instrumentation and a high-impact science program for the 4-m Mayall telescope at Kitt Peak. The BigBOSS instrument is a robotically-actuated, fiber-fed spectrograph capable of taking 5000 simultaneous spectra over a wavelength range from 340 nm to 1060 nm, with a resolution R = λ/Δλ = 3000-4800. Using data from imaging surveys that are already underway, spectroscopic targets are selected that trace the underlying dark matter distribution. In particular, targets include luminous red galaxies (LRGs) up to z = 1.0, extending the BOSS LRG survey in both redshift and survey area. To probe the universe out to even higher redshift, BigBOSS will target bright [OII] emission line galaxies (ELGs) up to z = 1.7. In total, 20 million galaxy redshifts are obtained to measure the BAO feature, trace the matter power spectrum at smaller scales, and detect redshift space distortions. BigBOSS will provide additional constraints on early dark energy and on the curvature of the universe by measuring the Ly-alpha forest in the spectra of over 600,000 2.2 max = 0.15), and could grow to over 600 if current work allows us to push the analysis to higher wave numbers (kmax = 0.3). BigBOSS will also place constraints on theories of modified gravity and inflation, and will measure the sum of neutrino masses to 0.024 eV accuracy.

  19. Low-cycle fatigue of turbine rotor wheels

    International Nuclear Information System (INIS)

    By means of low cycle fatigue achieved by the application of cyclic speed tests on turbine rotor wheels and in comparison with test values and by evaluating the formation of rim cracks caused by temperature change stress, the dangers of cracks appearing during operation in integrally moulded small gas turbine rotor wheels are assessed with the aid of fracture mechanisms. It was determined in short cycle tests that the objects under test with a higher stress gradient (1.0 mm-1) exhibited a higher endurance strength (104 stress cycle) than objects tested under a lower stress gradient. The results of these tests were put to discussion. In spite of a large dispersion of the cracking resistance factor Ksub(c), an additional operational life of up to 1,000 h could be approximated. Following further operational experience, it was shown that this approximation could be increased up to 2,000 h. (orig.)

  20. Local cyclic deformation behavior and microstructure of railway wheel materials

    International Nuclear Information System (INIS)

    The current investigations concentrate on the relation between the loading and environmental conditions, the local microstructure and the fatigue behavior of highly stressed railway wheel and tire steels. Experiments under stress control and total strain control were performed at ambient temperature with servohydraulic testing systems. Superimposed mean loadings allow an evaluation of cyclic creep and mean stress relaxation effects. Strain, temperature and electrical measuring techniques were used to characterize the cyclic deformation behavior of specimens from different depth positions of the cross-sections of UIC-specified wheel components (UIC: International Railway Union). The measured values show a strong interrelation. The microstructural characterization of the different material conditions was done by light and scanning electron microscopy together with digital image processing

  1. Rutting Resistance of Asphalt Overlay with Multilayer Wheel Tracking Test

    Institute of Scientific and Technical Information of China (English)

    LIAO Weidong; CHEN Zheng; WU Shaopeng; MO Liantong; LIU Gang

    2006-01-01

    The rutting resistance of multilayer asphalt overlay was researched by using laboratory wheel tracking test. The effects of loading level and test temperature on rutting resistance of asphalt overlay structure were evaluated by means of multilayer specimens .In comparison with multilayer tests, standard specimens of various layers were also conducted to evaluate the rutting resistance. Experimental results indicated that the test temperature and applied load have a significant effect on rutting resistance of asphalt concrete. Higher test temperature and heavier applied load resulted in higher rut depths. In addition, the mutilayer wheel tracking test has been demonstrated to be a more reasonable solution in evaluation on rutting resistance of asphatt pavement structure beasuse it reflects the cumulative permanent deformation in all of asphalt layers.

  2. Soil compaction and structural morphology under tractor wheelings

    Science.gov (United States)

    Shanahan, Peter; Quinton, John; Binley, Andrew; Silgram, Martyn

    2010-05-01

    Compaction of cultivated soils is a major problem for agriculture in terms of yield decline and sustainable soil resource management. Tramline wheelings exacerbate runoff and increase erosion from arable land. The UK Department for Environment, Food and Rural Affairs (Defra) LINK Project - a joint venture between agri-business, land managers and research groups - is currently evaluating a number of methods for alleviating compaction in tractor wheelings across a range of soil types in England. Using innovative applications of agri-geophysics (e.g. ground penetrating radar, electrical resistivity, acoustics and x-ray tomography), this current project aims to determine relationships between properties derived from geophysical methods (e.g. soil moisture, porosity), soil compaction and structural morphology. Such relationships are important for a clearer understanding of hydrological and biogeochemical processes in compacted soils, to address land management practices and develop cost-effective mitigation measures. Our poster will present some early results of this study.

  3. Characterizing the Perfonnance of the Wheel Electrostatic Spectrometer

    Science.gov (United States)

    Johansen, Michael R.; Mackey, P. J.; Holbert, E.; Clements, J. S.; Calle, C. I.

    2013-01-01

    A Wheel Electrostatic Spectrometer has been developed as a surveying tool to be incorporated into a planetary rover design. Electrostatic sensors with various protruding cover insulators are embedded into a prototype rover wheel. When these insulators come into contact with a surface, a charge develops on the cover insulator through tribocharging. A charge spectrum is created by analyzing the accumulated charge on each of the dissimilar cover insulators. We eventually intend to prove charge spectra can be used o determine differences in planetary regolith properties. We tested the effects of residual surface charge on the cover insulators and discovered a need to discharge the sensor cover insulators after each revolution. We proved the repeatability of the measurements for this sensor package and found that the sensor repeatability lies within one standard deviation of the noise in the signal.

  4. Experimental analysis and regression prediction of desiccant wheel behavior in high temperature heat pump and desiccant wheel air-conditioning system

    DEFF Research Database (Denmark)

    Sheng, Ying; Zhang, Yufeng; Sun, Yuexia;

    2014-01-01

    The objectives of this study are to evaluate the performance of desiccant wheel (DW) in the running system and obtain the useful data for practical application. The combined influences of multiple variables on the performance of desiccant wheel are investigated based on evaluating the indexes of ...

  5. Numerical Simulation Analysis of an Oversteer In-Wheel Small Electric Vehicle Integrated with Four-Wheel Drive and Independent Steering

    Directory of Open Access Journals (Sweden)

    Muhammad Izhar Ishak

    2016-01-01

    Full Text Available Similar to conventional vehicle, most in-wheel small EVs that exist today are designed with understeer (US characteristic. They are safer on the road but possess poor cornering performance. With recent in-wheel motor and steer-by wire technology, high cornering performance vehicle does not limit to sport or racing cars. We believe that oversteer (OS design approach for in-wheel small EV can increase the steering performance of the vehicle. However, one disadvantage is that OS vehicle has a stability limit velocity. In this paper, we proposed a Four-Wheel Drive and Independent Steering (4WDIS for in-wheel small EV with OS characteristic. The aim of implementing 4WDIS is to develop a high steer controllability and stability of the EV at any velocity. This paper analyses the performance of OS in-wheel small EV with 4WDIS by using numerical simulation. Two cornering conditions were simulated which are (1 steady-state cornering at below critical velocity and (2 steady-state cornering over critical velocity. The objective of the simulation is to understand the behavior of OS in-wheel small EV and the advantages of implementing the 4WDIS. The results show that an in-wheel small EV can achieve high cornering performance at low speed while maintaining stability at high speed.

  6. Modelling the effects of repeated wheel loads on soil profiles

    OpenAIRE

    Gräsle W.; Horn R.; Baumgartl T.; Richards B.C.

    1997-01-01

    Compaction of soil caused by increasing mechanical loads and repeated wheeling may result in reduced soil productivity. The physical response of soils to such loading is analysed with a non-linear finite element program using incremental tangential moduli with incremental loading and unloading from known initial conditions. During each load increment an iterative procedure is used to determine more accurately the stresses and the stress dependent moduli. This program is designed to model the ...

  7. EXPERIMENTAL EVALUATION OF ARTICULATED WHEELED VEHICLES POSITION STABILITY

    Directory of Open Access Journals (Sweden)

    Ye. Dubinin

    2015-07-01

    Full Text Available With introducing a mobile measurement system with linear acceleration sensors there was experimentally determined the parameter of position stability of the articulated wheeled vehicle on the example of HTA-200 «Slobozhanets». It was determined that the position stability was provided within the entire range of operating speeds and accelerations. The obtained results can be used to enhance the traffic safety of articulated vehicles.

  8. How Much Inflation is Necessary to Grease the Wheels?

    OpenAIRE

    Kim, Jinill; RUGE-MURCIA, Francisco J.

    2007-01-01

    This paper studies Tobin's proposition that inflation "greases" the wheels of the labor market. The analysis is carried out using a simple dynamic stochastic general equilibrium model with asymmetric wage adjustment costs. Optimal inflation is determined by a benevolent government that maximizes the households' welfare. The Simulated Method of Moments is used to estimate the nonlinear model based on its second-order approximation. Econometric results indicate that nominal wages are downwardly...

  9. Wear estimation of the wheel tyre in different service conditions

    Directory of Open Access Journals (Sweden)

    Henryk BĄKOWSKI

    2014-06-01

    Full Text Available In this article presented the results of fatigue strength test aluminium alloys using in car industry. Demonstrated distributions and values of stresses the wheel tyre made of aluminium alloys by means of FEM. In fatigue test used special machine, which can allow to determine Wohler diagram. In this way to determine the allowable stresses values in which do not occurring the damages.

  10. Teens Take the Wheel (A Cup of Health with CDC)

    Centers for Disease Control (CDC) Podcasts

    2015-10-22

    One of most noteworthy moments in a teenager’s life is earning a driver’s license. While it provides a newfound freedom, it also presents serious risks. In this podcast, Amy Jewett discusses ways to keep young drivers safe behind the wheel.  Created: 10/22/2015 by MMWR.   Date Released: 10/22/2015.

  11. Damage Caused by Wheeled Skidders on Cambisols of Central Europe

    OpenAIRE

    Allman, Michal; Ferenčík, Michal; Jankovský, Martin; Stanovský, Miroslav; Messingerová, Valéria

    2015-01-01

    Machine traffic and timber skidding significantly affect the soil surface and soil properties. The effects are mostly negative and result in soil erosion, worsening of soil properties and inhibition of the growth of roots and soil organisms. In this study, we evaluated forest soil damage caused by the HSM 805 HD wheeled skidder during timber skidding in selected forest stands in the School Forest Enterprise in Zvolen. We estimated the limits for operation of forest machines in the stands and ...

  12. Localization of Wheeled Mobile Robot Based on Extended Kalman Filtering

    Directory of Open Access Journals (Sweden)

    Li Guangxu

    2015-01-01

    Full Text Available A mobile robot localization method which combines relative positioning with absolute orientation is presented. The code salver and gyroscope are used for relative positioning, and the laser radar is used to detect absolute orientation. In this paper, we established environmental map, multi-sensor information fusion model, sensors and robot motion model. The Extended Kalman Filtering (EKF is adopted as multi-sensor data fusion technology to realize the precise localization of wheeled mobile robot.

  13. A mechanical model for deformable and mesh pattern wheel of lunar roving vehicle

    Science.gov (United States)

    Liang, Zhongchao; Wang, Yongfu; Chen, Gang (Sheng); Gao, Haibo

    2015-12-01

    As an indispensable tool for astronauts on lunar surface, the lunar roving vehicle (LRV) is of great significance for manned lunar exploration. An LRV moves on loose and soft lunar soil, so the mechanical property of its wheels directly affects the mobility performance. The wheels used for LRV have deformable and mesh pattern, therefore, the existing mechanical theory of vehicle wheel cannot be used directly for analyzing the property of LRV wheels. In this paper, a new mechanical model for LRV wheel is proposed. At first, a mechanical model for a rigid normal wheel is presented, which involves in multiple conventional parameters such as vertical load, tangential traction force, lateral force, and slip ratio. Secondly, six equivalent coefficients are introduced to amend the rigid normal wheel model to fit for the wheels with deformable and mesh-pattern in LRV application. Thirdly, the values of the six equivalent coefficients are identified by using experimental data obtained in an LRV's single wheel testing. Finally, the identified mechanical model for LRV's wheel with deformable and mesh pattern are further verified and validated by using additional experimental results.

  14. The Read Out Controller for the ATLAS New Small Wheel

    CERN Document Server

    Coliban, Radu Mihai; The ATLAS collaboration; Tulbure, Traian Tiberiu; Ivanovici, Mihail; Martoiu, Victor Sorin; Levinson, Lorne; Vermeulen, Jos

    2015-01-01

    In the upgrade process of the ATLAS detector, the innermost stations of the endcaps (Small Wheels, SW) will be replaced. The New Small Wheel (NSW) will have two chamber technologies, one for the Level-1 trigger function (small-strip Thin Gap Chambers, sTGC) and one primarily dedicated to precision tracking (Micromegas detectors, MM). Custom front-end Application Specific Integrated Circuits (ASICs) will be used to read and filter information from both the sTGC and MM detectors. In the context of the New Small Wheel data path, we designed the Read Out Controller (ROC) ASIC for handling, preprocessing and formatting the data generated by the NSW VMM upstream chips. The ROC will concentrate the data streams from 8 VMMs, filter data based on the BCID and transmit the data to FELIX via the L1DDC. ROC is composed of 8 VMM Capture modules, a cross-bar and 4 SubROC modules. The output data is sent via 4 high-speed e-links.

  15. Wheel arch aerodynamics of a modern road vehicle

    International Nuclear Information System (INIS)

    A geometrically faithful model of the Aston Martin V12 Vanquish was formed in 3D CAD and used to perform an extensive CFD study into the airflow in and around the wheel arch of the vehicle. Parameters such as spin ratio, ground clearance, vertical and horizontal insertion into the wheel arch and the yaw angles experienced during cornering, were all under investigation. The additional aim of the research was to validate or refute the use of CFD as a tool in this complex area of fluid flow. This research serves to highlight a number of problems and potential solutions in the use of CFD. Meshing problems can be eliminated with increased computational power and suggestions have been made to improve the modeling of rotating boundaries that include radial features such as wheel spokes. Much of the CFD data ties well with previously conducted experimental work, if not numerically then in trend. Without additional physical validation however, it is difficult to ascertain the overall accuracy and usefulness of the remaining results, which have not yet been conducted in physical reality. Despite its limitations, the use of CFD permitted an extensive analysis in a comparatively short length of time and served to highlight potential areas for increased scrutiny. As an example, results from the final yaw angle case drew attention to a potential concern for aerodynamic destabilisation of the vehicle during cornering, generating lift on the front arch of the car that is already lifted due to cornering forces and body roll. (author)

  16. The Read Out Controller for the ATLAS New Small Wheel

    International Nuclear Information System (INIS)

    In the upgrade process of the ATLAS detector, the innermost stations of the endcaps (Small Wheels) will be replaced. The New Small Wheel will have two chamber technologies, small-strip Thin Gap Chambers and Micromegas, each providing triggering and precision track measurement. Custom front-end Application Specific Integrated Circuits will be used to read and filter information from both types of detectors. In the context of the New Small Wheel data path, the Read Out Controller ASIC is used for handling, preprocessing and formatting the data generated by the VMM upstream chips. The Read Out Controller will concentrate the data streams from 8 VMMs, filter data based on the ATLAS Level-1 trigger which identifies bunch crossings of interest and transmit the data to FELIX via the L1DDC. The Read Out Controller is composed of 8 VMM Capture modules, a cross-bar and 4 sROC modules. The output data is sent via up to 4 serial links with a configurable speed of 80, 160 or 320 Mbps per link

  17. Stability Simulation of a Vehicle with Wheel Active Steering

    Directory of Open Access Journals (Sweden)

    Brabec Pavel

    2016-01-01

    Full Text Available This paper deals with the possibility of increasing the vehicle driving stability at a higher speed. One of the ways how to achieve higher stability is using the 4WS system. Mathematical description of vehicle general movement is a very complex task. For simulation, models which are aptly simplified are used. For the first approach, so-called single-truck vehicle model (often linear is usually used. For the simulation, we have chosen to extend the model into a two-truck one, which includes the possibility to input more vehicle parameters. Considering the 4WS system, it is possible to use a number of potential regulations. In our simulation model, the regulation system with compound coupling was used. This type of regulation turns the rear wheels depending on the input parameters of the system (steering angle of the front wheels and depending on the output moving quantities of the vehicle, most frequently the yaw rate. Criterion for compensation of lateral deflection centre of gravity angle is its zero value, or more precisely the zero value of its first-order derivative. Parameters and set-up of the simulation model were done in conjunction with the dSAPACE software. Reference performances of the vehicle simulation model were made through the defined manoeuvres. But the simulation results indicate that the rear-wheels steering can have a positive effect on the vehicle movement stability, especially when changing the driving direction at high speed.

  18. ANALYSIS OF CREEP FORCES OF WHEEL/RAIL

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The effects of structure elastic deformations of wheelset and track on creep forces of wheel and rail are investigated.Finite element method is used to calculate the influence coefficients expressing the relations between structure elastic deformations of wheelset and track and the corresponding loads in the rolling direction and the lateral direction of wheelset,respectively.The influence coefficients of wheelset and track are used to revise some of the influence coefficients obtained with the formula of Bossinesq and Cerruti in Kalker's theory of three-dimensional elastic bodies in rolling contact with non-Hertzian form.The theory of Kalker and the modified theory of Kalker are respectively employed to analyze creep forces of wheelset and track.The numerical results obtained show a great influence of structure elastic deformations of wheelset and track on the creep forces.Therfore it is not reasonable that wheel and rail are treated as elastic half space in the analysis of wheel and rail in rolling contact,and the present theories of rolling contact based on the assumption of elastic half space need to be further improved.

  19. Structure Analysis of a Turbocharger Compressor Wheel Using FEA

    Directory of Open Access Journals (Sweden)

    Shaik Mohammad Rafi

    2014-10-01

    Full Text Available When people talk about race cars or high-performance sports cars, the topic of turbochargers usually comes up. Turbochargers also appear on large diesel engines. A turbo can significantly boost an engine's horsepower without significantly increasing its weight, which is the huge benefit that makes turbos so popular. Turbochargers are a type of forced induction system. They compress the air flowing into the engine. The advantage of compressing the air is that it lets the engine squeeze more air into a cylinder, and more air means that more fuel can be added. Therefore, you get more power from each explosion in each cylinder. Here in this project we are designing the compressor wheel by using Pro-E and doing analysis by using FEA package. The main aim of the project is to increase the performance of the compressor wheel for this we are changing the material and also we are changing the existing design. By comparing the results we will get the best model from this data we suggests the design modifications to the company to improve the performance of the compressor wheel.

  20. New Record Five-Wheel Drive, Spirit's Sol 1856

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Spirit used its navigation camera to take the images that have been combined into this stereo, 180-degree view of the rover's surroundings during the 1,856th Martian day, or sol, of Spirit's surface mission (March 23, 2009). The center of the view is toward the west-southwest. The rover had driven 25.82 meters (84.7 feet) west-northwestward earlier on Sol 1856. This is the longest drive on Mars so far by a rover using only five wheels. Spirit lost the use of its right-front wheel in March 2006. Before Sol 1856, the farthest Spirit had covered in a single sol's five-wheel drive was 24.83 meters (81.5 feet), on Sol 1363 (Nov. 3, 2007). The Sol 1856 drive made progress on a route planned for taking Spirit around the western side of the low plateau called 'Home Plate.' A portion of the northwestern edge of Home Plate is prominent in the left quarter of this image, toward the south. This view is presented as a cylindrical projection with geometric seam correction.

  1. Global Fluctuation Spectra in Big Crunch/Big Bang String Vacua

    OpenAIRE

    Craps, Ben; Ovrut, Burt A.

    2003-01-01

    We study Big Crunch/Big Bang cosmologies that correspond to exact world-sheet superconformal field theories of type II strings. The string theory spacetime contains a Big Crunch and a Big Bang cosmology, as well as additional ``whisker'' asymptotic and intermediate regions. Within the context of free string theory, we compute, unambiguously, the scalar fluctuation spectrum in all regions of spacetime. Generically, the Big Crunch fluctuation spectrum is altered while passing through the bounce...

  2. Effect of wheelset flexibility on wheel-rail contact behavior and a specific coupling of wheel-rail contact to flexible wheelset

    Science.gov (United States)

    Zhong, Shuoqiao; Xiao, Xinbiao; Wen, Zefeng; Jin, Xuesong

    2016-04-01

    The flexibility of a train's wheelset can have a large effect on vehicle-track dynamic responses in the medium to high frequency range. To investigate the effects of wheelset bending and axial deformation of the wheel web, a specific coupling of wheel-rail contact with a flexible wheelset is presented and integrated into a conventional vehicle-track dynamic system model. Both conventional and the proposed dynamic system models are used to carry out numerical analyses on the effects of wheelset bending and axial deformation of the wheel web on wheel-rail rolling contact behaviors. Excitations with various irregularities and speeds were considered. The irregularities included measured track irregularity and harmonic irregularities with two different wavelengths. The speeds ranged from 200 to 400 km/h. The results show that the proposed model can characterize the effects of flexible wheelset deformation on the wheel-rail rolling contact behavior very well.

  3. Big Bang Day : The Great Big Particle Adventure - 3. Origins

    CERN Multimedia

    2008-01-01

    In this series, comedian and physicist Ben Miller asks the CERN scientists what they hope to find. If the LHC is successful, it will explain the nature of the Universe around us in terms of a few simple ingredients and a few simple rules. But the Universe now was forged in a Big Bang where conditions were very different, and the rules were very different, and those early moments were crucial to determining how things turned out later. At the LHC they can recreate conditions as they were billionths of a second after the Big Bang, before atoms and nuclei existed. They can find out why matter and antimatter didn't mutually annihilate each other to leave behind a Universe of pure, brilliant light. And they can look into the very structure of space and time - the fabric of the Universe

  4. Perspectives on Big Data and Big Data Analytics

    Directory of Open Access Journals (Sweden)

    Elena Geanina ULARU

    2012-12-01

    Full Text Available Nowadays companies are starting to realize the importance of using more data in order to support decision for their strategies. It was said and proved through study cases that “More data usually beats better algorithms”. With this statement companies started to realize that they can chose to invest more in processing larger sets of data rather than investing in expensive algorithms. The large quantity of data is better used as a whole because of the possible correlations on a larger amount, correlations that can never be found if the data is analyzed on separate sets or on a smaller set. A larger amount of data gives a better output but also working with it can become a challenge due to processing limitations. This article intends to define the concept of Big Data and stress the importance of Big Data Analytics.

  5. Antigravity and the big crunch/big bang transition

    International Nuclear Information System (INIS)

    We point out a new phenomenon which seems to be generic in 4d effective theories of scalar fields coupled to Einstein gravity, when applied to cosmology. A lift of such theories to a Weyl-invariant extension allows one to define classical evolution through cosmological singularities unambiguously, and hence construct geodesically complete background spacetimes. An attractor mechanism ensures that, at the level of the effective theory, generic solutions undergo a big crunch/big bang transition by contracting to zero size, passing through a brief antigravity phase, shrinking to zero size again, and re-emerging into an expanding normal gravity phase. The result may be useful for the construction of complete bouncing cosmologies like the cyclic model.

  6. Solution of a braneworld big crunch/big bang cosmology

    International Nuclear Information System (INIS)

    We solve for the cosmological perturbations in a five-dimensional background consisting of two separating or colliding boundary branes, as an expansion in the collision speed V divided by the speed of light c. Our solution permits a detailed check of the validity of four-dimensional effective theory in the vicinity of the event corresponding to the big crunch/big bang singularity. We show that the four-dimensional description fails at the first nontrivial order in (V/c)2. At this order, there is nontrivial mixing of the two relevant four-dimensional perturbation modes (the growing and decaying modes) as the boundary branes move from the narrowly separated limit described by Kaluza-Klein theory to the well-separated limit where gravity is confined to the positive-tension brane. We comment on the cosmological significance of the result and compute other quantities of interest in five-dimensional cosmological scenarios

  7. Antigravity and the big crunch/big bang transition

    Energy Technology Data Exchange (ETDEWEB)

    Bars, Itzhak [Department of Physics and Astronomy, University of Southern California, Los Angeles, CA 90089-2535 (United States); Chen, Shih-Hung [Perimeter Institute for Theoretical Physics, Waterloo, ON N2L 2Y5 (Canada); Department of Physics and School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85287-1404 (United States); Steinhardt, Paul J., E-mail: steinh@princeton.edu [Department of Physics and Princeton Center for Theoretical Physics, Princeton University, Princeton, NJ 08544 (United States); Turok, Neil [Perimeter Institute for Theoretical Physics, Waterloo, ON N2L 2Y5 (Canada)

    2012-08-29

    We point out a new phenomenon which seems to be generic in 4d effective theories of scalar fields coupled to Einstein gravity, when applied to cosmology. A lift of such theories to a Weyl-invariant extension allows one to define classical evolution through cosmological singularities unambiguously, and hence construct geodesically complete background spacetimes. An attractor mechanism ensures that, at the level of the effective theory, generic solutions undergo a big crunch/big bang transition by contracting to zero size, passing through a brief antigravity phase, shrinking to zero size again, and re-emerging into an expanding normal gravity phase. The result may be useful for the construction of complete bouncing cosmologies like the cyclic model.

  8. Antigravity and the big crunch/big bang transition

    Science.gov (United States)

    Bars, Itzhak; Chen, Shih-Hung; Steinhardt, Paul J.; Turok, Neil

    2012-08-01

    We point out a new phenomenon which seems to be generic in 4d effective theories of scalar fields coupled to Einstein gravity, when applied to cosmology. A lift of such theories to a Weyl-invariant extension allows one to define classical evolution through cosmological singularities unambiguously, and hence construct geodesically complete background spacetimes. An attractor mechanism ensures that, at the level of the effective theory, generic solutions undergo a big crunch/big bang transition by contracting to zero size, passing through a brief antigravity phase, shrinking to zero size again, and re-emerging into an expanding normal gravity phase. The result may be useful for the construction of complete bouncing cosmologies like the cyclic model.

  9. Antigravity and the big crunch/big bang transition

    CERN Document Server

    Bars, Itzhak; Steinhardt, Paul J; Turok, Neil

    2011-01-01

    We point out a new phenomenon which seems to be generic in 4d effective theories of scalar fields coupled to Einstein gravity, when applied to cosmology. A lift of such theories to a Weyl-invariant extension allows one to define classical evolution through cosmological singularities unambiguously, and hence construct geodesically complete background spacetimes. An attractor mechanism ensures that, at the level of the effective theory, generic solutions undergo a big crunch/big bang transition by contracting to zero size, passing through a brief antigravity phase, shrinking to zero size again, and re-emerging into an expanding normal gravity phase. The result may be useful for the construction of complete bouncing cosmologies like the cyclic model.

  10. Web Science Big Wins: Information Big Bang & Fundamental Constants

    OpenAIRE

    Carr, Les

    2010-01-01

    We take for granted a Web that provides free and unrestricted information exchange, but the Web is under pressure to change in order to respond to issues of security, commerce, criminality, privacy. Web Science needs to explain how the Web impacts society and predict the outcomes of proposed changes to Web infrastructure on business and society. Using the analogy of the Big Bang, this presentation describes how the Web spread the conditions of its initial creation throughout the whole of soci...

  11. Big Data – Big Deal for Organization Design?

    OpenAIRE

    Janne J. Korhonen

    2014-01-01

    Analytics is an increasingly important source of competitive advantage. It has even been posited that big data will be the next strategic emphasis of organizations and that analytics capability will be manifested in organizational structure. In this article, I explore how analytics capability might be reflected in organizational structure using the notion of  “requisite organization” developed by Jaques (1998). Requisite organization argues that a new strategic emphasis requires the addition ...

  12. Nástroje pro Big Data Analytics

    OpenAIRE

    Miloš, Marek

    2013-01-01

    The thesis covers the term for specific data analysis called Big Data. The thesis firstly defines the term Big Data and the need for its creation because of the rising need for deeper data processing and analysis tools and methods. The thesis also covers some of the technical aspects of Big Data tools, focusing on Apache Hadoop in detail. The later chapters contain Big Data market analysis and describe the biggest Big Data competitors and tools. The practical part of the thesis presents a way...

  13. ISSUES, CHALLENGES, AND SOLUTIONS: BIG DATA MINING

    Directory of Open Access Journals (Sweden)

    Jaseena K.U.

    2014-12-01

    Full Text Available Data has become an indispensable part of every economy, industry, organization, business function and individual. Big Data is a term used to identify the datasets that whose size is beyond the ability of typical database software tools to store, manage and analyze. The Big Data introduce unique computational and statistical challenges, including scalability and storage bottleneck, noise accumulation, spurious correlation and measurement errors. These challenges are distinguished and require new computational and statistical paradigm. This paper presents the literature review about the Big data Mining and the issues and challenges with emphasis on the distinguished features of Big Data. It also discusses some methods to deal with big data.

  14. Pneumatic locking device for magnetic bearing reaction wheel

    Science.gov (United States)

    Privat, Michel; da Costa, Arlindo

    2003-09-01

    Due to the launch vibration environment, the use of locking device is necessary for large or heavy mechanisms. This remark is true in particular for the inertial actuators like magnetic bearing reaction wheels. These actuators have a rotor that is in magnetic levitation without any contact with the stator. Locking device is mandatory to maintain the rotor during the launch vibrations. To avoid contact between rotor and stator during the functional phase, the link created by the locking device must be completely released. This article presents a pneumatic locking device with pyrotechnical sub-systems that have been realised by "ALCATEL Space Industries" for the reaction wheels development in the frame of a CNES satellites family. The first paragraph presents the wheel functioning and briefly describes the Electro-mechanical components of the reaction wheel. The second paragraph describes a device based on a metallic bellows ring. A nitrogen pressure in the ring allows pushing the rotor against the stator. The rotor release is obtained by drilling the system tubing with a pyrotechnic valve. The third point describes the qualification tests and the resulting data. Some functional tests are made in warm and cold case with the locking device in order to improve some mechanical characteristics including the locking effort generated and the leakage rate. Launch vibrations and thermal tests have been realised and the good functioning of the mechanism is proven. At the end of these tests, the qualification has been pronounced. The device is now implemented within the reaction wheel. This equipment should flight in 2004. The next paragraph presents the works realised under CNES Research and Technology contract. The objectives were the characterisation of metallic bellows and some technological studies to improve the knowledge of the mechanical and functional characteristics of these elements. The first study was to create a Finite Element model of a bellow in order to

  15. Big data is not a monolith

    CERN Document Server

    Sugimoto, Cassidy R; Mattioli, Michael

    2016-01-01

    Big data is ubiquitous but heterogeneous. Big data can be used to tally clicks and traffic on web pages, find patterns in stock trades, track consumer preferences, identify linguistic correlations in large corpuses of texts. This book examines big data not as an undifferentiated whole but contextually, investigating the varied challenges posed by big data for health, science, law, commerce, and politics. Taken together, the chapters reveal a complex set of problems, practices, and policies. The advent of big data methodologies has challenged the theory-driven approach to scientific knowledge in favor of a data-driven one. Social media platforms and self-tracking tools change the way we see ourselves and others. The collection of data by corporations and government threatens privacy while promoting transparency. Meanwhile, politicians, policy makers, and ethicists are ill-prepared to deal with big data's ramifications. The contributors look at big data's effect on individuals as it exerts social control throu...

  16. Multispectral Imager With Improved Filter Wheel and Optics

    Science.gov (United States)

    Bremer, James C.

    2007-01-01

    Figure 1 schematically depicts an improved multispectral imaging system of the type that utilizes a filter wheel that contains multiple discrete narrow-band-pass filters and that is rotated at a constant high speed to acquire images in rapid succession in the corresponding spectral bands. The improvement, relative to prior systems of this type, consists of the measures taken to prevent the exposure of a focal-plane array (FPA) of photodetectors to light in more than one spectral band at any given time and to prevent exposure of the array to any light during readout. In prior systems, these measures have included, variously the use of mechanical shutters or the incorporation of wide opaque sectors (equivalent to mechanical shutters) into filter wheels. These measures introduce substantial dead times into each operating cycle intervals during which image information cannot be collected and thus incoming light is wasted. In contrast, the present improved design does not involve shutters or wide opaque sectors, and it reduces dead times substantially. The improved multispectral imaging system is preceded by an afocal telescope and includes a filter wheel positioned so that its rotation brings each filter, in its turn, into the exit pupil of the telescope. The filter wheel contains an even number of narrow-band-pass filters separated by narrow, spoke-like opaque sectors. The geometric width of each filter exceeds the cross-sectional width of the light beam coming out of the telescope. The light transmitted by the sequence of narrow-band filters is incident on a dichroic beam splitter that reflects in a broad shorter-wavelength spectral band that contains half of the narrow bands and transmits in a broad longer-wavelength spectral band that contains the other half of the narrow spectral bands. The filters are arranged on the wheel so that if the pass band of a given filter is in the reflection band of the dichroic beam splitter, then the pass band of the adjacent filter

  17. Plastic Deformation and Softening of the Surface Layer of Railway Wheel

    Directory of Open Access Journals (Sweden)

    Ławrynowicz Z.

    2015-12-01

    Full Text Available In this study scanning electron microscope (SEM and optical micrograph observations were used to investigate the plastic deformation near the surface of the worn railway wheel following service. Microstructure, plastic deformation and micro-hardness of the material in the outermost tread layer of used passenger railway wheel were characterised. It was found that the material in the contact surface of wheel undergoes severe plastic deformation. Vickers micro-hardness measurements in the highly deformed layer could be correlated with softening of the outer wheel rim and the spheroidisation of the cementite phase. Examination of worn, railway wheel taken out of service, has indicated that cracks are predominantly initiated at the wheel surface down the edges of highly strained, pro-eutectoid ferrite zones (situated along prior austenite grain boundaries and that such pro-eutectoid ferrite zones also facilitate crack propagation.

  18. A quasi-static model of wheel-tissue interaction for surgical robotics.

    Science.gov (United States)

    Wang, Xin; Sliker, Levin J; Qi, H Jerry; Rentschler, Mark E

    2013-09-01

    Wheel-driven mobile in vivo robotic devices can provide an unconstrained platform for visualization and task performance. Careful understanding of the wheel-tissue interaction is necessary to predict in vivo performance of medical mobility systems. Here, an analytical study of the friction involving rolling contact of a surgical wheel, moving at constant velocities over soft tissue, is presented and verified. A quasi-static frictionless solution is first derived from existing theory, and newly developed theory considering frictional effects is later introduced. In this analysis, the effect of friction on wheel mobility over a viscoelastic substrate is analyzed with wheel velocity as the only changing variable. The analytical model is later verified by experiments and Finite Element Method (FEM) simulations. A simple application of this model to help design a surgical robot is also presented. Additional results indicate that the resistance force, which arises from the tissue viscosity, approaches zero for small and very large wheel velocities. PMID:23582337

  19. Theoretical prediction of the damping of a railway wheel with sandwich-type dampers

    Science.gov (United States)

    Merideno, Inaki; Nieto, Javier; Gil-Negrete, Nere; Giménez Ortiz, José Germán; Landaberea, Aitor; Iartza, Jon

    2014-09-01

    This paper presents a procedure for predicting the damping added to a railway wheel when sandwich-type dampers are installed. Although there are different ways to reduce the noise generated by a railway wheel, most devices are based on the mechanism of increasing wheel damping. This is why modal damping ratios are a clear indicator of the efficiency of the damping device and essential when a vibro-acoustic study of a railway wheel is carried out. Based on a number of output variables extracted from the wheel and damper models, the strategy explained herein provides the final damping ratios of the damped wheel. Several different configurations are designed and experimentally tested. Theoretical and experimental results agree adequately, and it is demonstrated that this procedure is a good tool for qualitative comparison between different solutions in the design stages.

  20. Three-dimensional elastic-plastic finite element analysis for wheel-rail rolling contact fatigue

    Directory of Open Access Journals (Sweden)

    Taek-Young Kim

    2014-07-01

    Full Text Available Rolling contact fatigue of an urban railway wheel was analysed during its rolling FEM analysis was performed using 3D modelling of rail and wheel, in which the slope of the rail and nonlinear isotropic and kinematic hardening behavior of the rail and the wheel were considered. The maximum von Mises stress and contact pressure between the rail and wheel were determined under an axial load of 85 kN. The contact pressure distributions calculated using elastic Hertz theory and three-dimensional elastic–plastic stress analysis are compared. The maximum contact pressure of the wheel from the elasticplastic FE method is slightly lower than the value from Hertz contact theory with elastic deformation. The rolling contact fatigue (RCF of the wheel due to rolling contact was determined to be infinite by Dang Van criterion.

  1. Design optimization on the front wheel orientation parameters of a vehicle

    Institute of Scientific and Technical Information of China (English)

    CHU Zhigang; DENG Zhaoxiang; HU Yumei; ZHU Ming

    2003-01-01

    A uniform optimization object function for front wheel orientation parameters of a vehicle is reported, which includes the tolerances of practical values and set values of front wheel orientation parameters under full load, and the changing value of each parameter with front wheel fluctuation to build a front suspension model for optimization analysis based on the multi-body dynamic (MD) theory. The original suspension is optimized with this model, and the variation law of each parameter with front wheel fluctuation is obtained. The results of a case study demonstrate that the front wheel orientation parameters of the optimized vehicle are reasonable under typical conditions and the variation of each parameter is in an ideal range with the wheel fluctuating within ±40 mm. In addition, the driving performance is improved greatly in the road test and practical use.

  2. Big Numbers in String Theory

    CERN Document Server

    Schellekens, A N

    2016-01-01

    This paper contains some personal reflections on several computational contributions to what is now known as the "String Theory Landscape". It consists of two parts. The first part concerns the origin of big numbers, and especially the number $10^{1500}$ that appeared in work on the covariant lattice construction (with W. Lerche and D. Luest). This part contains some new results. I correct a huge but inconsequential error, discuss some more accurate estimates, and compare with the counting for free fermion constructions. In particular I prove that the latter only provide an exponentially small fraction of all even self-dual lattices for large lattice dimensions. The second part of the paper concerns dealing with big numbers, and contains some lessons learned from various vacuum scanning projects.

  3. George and the big bang

    CERN Document Server

    Hawking, Lucy; Parsons, Gary

    2012-01-01

    George has problems. He has twin baby sisters at home who demand his parents’ attention. His beloved pig Freddy has been exiled to a farm, where he’s miserable. And worst of all, his best friend, Annie, has made a new friend whom she seems to like more than George. So George jumps at the chance to help Eric with his plans to run a big experiment in Switzerland that seeks to explore the earliest moment of the universe. But there is a conspiracy afoot, and a group of evildoers is planning to sabotage the experiment. Can George repair his friendship with Annie and piece together the clues before Eric’s experiment is destroyed forever? This engaging adventure features essays by Professor Stephen Hawking and other eminent physicists about the origins of the universe and ends with a twenty-page graphic novel that explains how the Big Bang happened—in reverse!

  4. Big data and ophthalmic research.

    Science.gov (United States)

    Clark, Antony; Ng, Jonathon Q; Morlet, Nigel; Semmens, James B

    2016-01-01

    Large population-based health administrative databases, clinical registries, and data linkage systems are a rapidly expanding resource for health research. Ophthalmic research has benefited from the use of these databases in expanding the breadth of knowledge in areas such as disease surveillance, disease etiology, health services utilization, and health outcomes. Furthermore, the quantity of data available for research has increased exponentially in recent times, particularly as e-health initiatives come online in health systems across the globe. We review some big data concepts, the databases and data linkage systems used in eye research-including their advantages and limitations, the types of studies previously undertaken, and the future direction for big data in eye research. PMID:26844660

  5. Big Bounce in Dipole Cosmology

    OpenAIRE

    Battisti, Marco Valerio; Marciano, Antonino

    2010-01-01

    We derive the cosmological Big Bounce scenario from the dipole approximation of Loop Quantum Gravity. We show that a non-singular evolution takes place for any matter field and that, by considering a massless scalar field as a relational clock for the dynamics, the semi-classical proprieties of an initial state are preserved on the other side of the bounce. This model thus enhances the relation between Loop Quantum Cosmology and the full theory.

  6. BIG DATA IN BUSINESS ENVIRONMENT

    OpenAIRE

    Logica BANICA; Alina HAGIU

    2015-01-01

    In recent years, dealing with a lot of data originating from social media sites and mobile communications among data from business environments and institutions, lead to the definition of a new concept, known as Big Data. The economic impact of the sheer amount of data produced in a last two years has increased rapidly. It is necessary to aggregate all types of data (structured and unstructured) in order to improve current transactions, to develop new business models, to provide a real image ...

  7. BIG Data – A Review.

    OpenAIRE

    Anuradha Bhatia; Gaurav Vaswani

    2013-01-01

    As more data becomes available from an abundance of sources both within and outside, organizations are seeking to use those abundant resources to increase innovation, retain customers, and increase operational efficiency. At the same time, organizations are challenged by their end users, who are demanding greater capability and integration to mine and analyze burgeoning new sources of information. Big Data provides opportunities for business users to ask questions they never were able to ask ...

  8. Big data processing with Hadoop

    OpenAIRE

    Wu, Shiqi

    2015-01-01

    Computing technology has changed the way we work, study, and live. The distributed data processing technology is one of the popular topics in the IT field. It provides a simple and centralized computing platform by reducing the cost of the hardware. The characteristics of distributed data processing technology have changed the whole industry. Hadoop, as the open source project of Apache foundation, is the most representative platform of distributed big data processing. The Hadoop distribu...

  9. Big Bang Nucleosynthesis: An Update

    OpenAIRE

    Olive, Keith A.; Scully, Sean T.

    1995-01-01

    WThe current status of big bang nucleosynthesis is reviewed with an emphasis on the comparison between the observational determination of the light element abundances of \\D, \\he3, \\he4 and \\li7 and the predictions from theory. In particular, we present new analyses for \\he4 and \\li7. Implications for physics beyond the standard model are also discussed. Limits on the effective number of neutrino flavors are also updated.

  10. Industrialization and the Big Push

    OpenAIRE

    1988-01-01

    This paper explores Rosenstein-Rodman's (1943) idea that simultaneous industrialization of many sectors of the economy can be profitable for all of them, even when no sector can break even industrializing alone. We analyze this ides in the context of an imperfectly competitive economy with aggregate demand spillovers, and interpret the big push into industrialization as a move from a bad to a good equilibrium. We show that for two equilibria to exist, it must be the case that an industrializi...

  11. Pragmatic Interaction between Big Powers

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Lu. It is very difficult to summarize the relationship among big powers in 2004. Looking east, there existed a """"small cold war"""" named by some media between Europe and Russia and between the United States and Russia; with regard to the """"orange revolution"""" in Ukraine at the end of the year, a rival show rope and Russia. Looking east, awas displayed between America, Eufresh scent seems to fill the air.

  12. The BigBOSS Experiment

    CERN Document Server

    Schlegel, D; Abraham, T; Ahn, C; Prieto, C Allende; Annis, J; Aubourg, E; Azzaro, M; Baltay, S Bailey C; Baugh, C; Bebek, C; Becerril, S; Blanton, M; Bolton, A; Bromley, B; Cahn, R; Carton, P -H; Cervantes-Cota, J L; Chu, Y; Cortes, M; Dawson, K; Dey, A; Dickinson, M; Diehl, H T; Doel, P; Ealet, A; Edelstein, J; Eppelle, D; Escoffier, S; Evrard, A; Faccioli, L; Frenk, C; Geha, M; Gerdes, D; Gondolo, P; Gonzalez-Arroyo, A; Grossan, B; Heckman, T; Heetderks, H; Ho, S; Honscheid, K; Huterer, D; Ilbert, O; Ivans, I; Jelinsky, P; Jing, Y; Joyce, D; Kennedy, R; Kent, S; Kieda, D; Kim, A; Kim, C; Kneib, J -P; Kong, X; Kosowsky, A; Krishnan, K; Lahav, O; Lampton, M; LeBohec, S; Brun, V Le; Levi, M; Li, C; Liang, M; Lim, H; Lin, W; Linder, E; Lorenzon, W; de la Macorra, A; Magneville, Ch; Malina, R; Marinoni, C; Martinez, V; Majewski, S; Matheson, T; McCloskey, R; McDonald, P; McKay, T; McMahon, J; Menard, B; Miralda-Escude, J; Modjaz, M; Montero-Dorta, A; Morales, I; Mostek, N; Newman, J; Nichol, R; Nugent, P; Olsen, K; Padmanabhan, N; Palanque-Delabrouille, N; Park, I; Peacock, J; Percival, W; Perlmutter, S; Peroux, C; Petitjean, P; Prada, F; Prieto, E; Prochaska, J; Reil, K; Rockosi, C; Roe, N; Rollinde, E; Roodman, A; Ross, N; Rudnick, G; Ruhlmann-Kleider, V; Sanchez, J; Sawyer, D; Schimd, C; Schubnell, M; Scoccimaro, R; Seljak, U; Seo, H; Sheldon, E; Sholl, M; Shulte-Ladbeck, R; Slosar, A; Smith, D S; Smoot, G; Springer, W; Stril, A; Szalay, A S; Tao, C; Tarle, G; Taylor, E; Tilquin, A; Tinker, J; Valdes, F; Wang, J; Wang, T; Weaver, B A; Weinberg, D; White, M; Wood-Vasey, M; Yang, J; Yeche, X Yang Ch; Zakamska, N; Zentner, A; Zhai, C; Zhang, P

    2011-01-01

    BigBOSS is a Stage IV ground-based dark energy experiment to study baryon acoustic oscillations (BAO) and the growth of structure with a wide-area galaxy and quasar redshift survey over 14,000 square degrees. It has been conditionally accepted by NOAO in response to a call for major new instrumentation and a high-impact science program for the 4-m Mayall telescope at Kitt Peak. The BigBOSS instrument is a robotically-actuated, fiber-fed spectrograph capable of taking 5000 simultaneous spectra over a wavelength range from 340 nm to 1060 nm, with a resolution R = 3000-4800. Using data from imaging surveys that are already underway, spectroscopic targets are selected that trace the underlying dark matter distribution. In particular, targets include luminous red galaxies (LRGs) up to z = 1.0, extending the BOSS LRG survey in both redshift and survey area. To probe the universe out to even higher redshift, BigBOSS will target bright [OII] emission line galaxies (ELGs) up to z = 1.7. In total, 20 million galaxy red...

  13. Big data: the management revolution.

    Science.gov (United States)

    McAfee, Andrew; Brynjolfsson, Erik

    2012-10-01

    Big data, the authors write, is far more powerful than the analytics of the past. Executives can measure and therefore manage more precisely than ever before. They can make better predictions and smarter decisions. They can target more-effective interventions in areas that so far have been dominated by gut and intuition rather than by data and rigor. The differences between big data and analytics are a matter of volume, velocity, and variety: More data now cross the internet every second than were stored in the entire internet 20 years ago. Nearly real-time information makes it possible for a company to be much more agile than its competitors. And that information can come from social networks, images, sensors, the web, or other unstructured sources. The managerial challenges, however, are very real. Senior decision makers have to learn to ask the right questions and embrace evidence-based decision making. Organizations must hire scientists who can find patterns in very large data sets and translate them into useful business information. IT departments have to work hard to integrate all the relevant internal and external sources of data. The authors offer two success stories to illustrate how companies are using big data: PASSUR Aerospace enables airlines to match their actual and estimated arrival times. Sears Holdings directly analyzes its incoming store data to make promotions much more precise and faster. PMID:23074865

  14. Plastic Deformation and Softening of the Surface Layer of Railway Wheel

    OpenAIRE

    Ławrynowicz Z.

    2015-01-01

    In this study scanning electron microscope (SEM) and optical micrograph observations were used to investigate the plastic deformation near the surface of the worn railway wheel following service. Microstructure, plastic deformation and micro-hardness of the material in the outermost tread layer of used passenger railway wheel were characterised. It was found that the material in the contact surface of wheel undergoes severe plastic deformation. Vickers micro-hardness measurements in the highl...

  15. A comparison of aircraft tire skid with initial wheel rotational speed using ANSYS transient simulation

    OpenAIRE

    Alroqi, Abdurrhman A; Wang, Weiji

    2016-01-01

    Based on heavy aircraft main landing gear tires touchdown skidding process, patents have been registered since the 1940s to improve tire safety, decrease the substantial wear and smoke that results from every landing by spinning the rear wheels before touchdown. A single wheel has been modeled as a mass-spring-damper system using ANSYS mechanical transient simulation to analyze static and pre-rotating wheels behavior during a short period between touchdown and skidding, to spin-up to reach th...

  16. Design and Development of a Compact Magnetic Bearing Momentum Wheel for Micro and Small Satellites

    OpenAIRE

    Scharfe, Michael; Roschke, Thomas; Bindl, Enrico; Blonski, Daniel

    2001-01-01

    Reaction and momentum wheels have become standard equipment for three-axis attitude stabilisation of conventional satellite classes as used e.g. for telecommunication and remote sensing missions. Owing to very compact mechanical designs and highly integrated electronics, wheels are now also more and more interesting for small satellites up to 100…200 kg with increasingly demanding requirements on attitude control. Wheels suitable for small satellites have a typical momentum capacity up to app...

  17. APPLIED PROBLEMS OF CURVILINEAR MOTION DYNAMICS OF ALL-WHEEL DRIVE TRACTION MEANS

    Directory of Open Access Journals (Sweden)

    G. S. Gorin

    2014-01-01

    Full Text Available Fundamental principles for hybrid theory on turning of an all-wheel drive system are given in the paper. The paper shows expediency of accounting longitudinal additional tangential reactions (parasitic forces in contacts of central and lateral wheels with foundation. Algorithms for calculating additional tangential reactions have been proposed in the paper. The paper presents calculation kinematics model for turning of steered and rigid bogie with inter-wheel differential at various axial drive.

  18. On graphs that do not contain a theta nor a wheel Part I: two subclasses

    OpenAIRE

    Diot, Emilie; Radovanovic, Marko; Trotignon, Nicolas; Vuskovic, Kristina

    2015-01-01

    Truemper configurations are four types of graphs (namely thetas, wheels, prisms and pyramids) that play an important role in the proof of several decomposition theorems for hereditary graph classes. In this paper, we prove two structure theorems: one for graphs with no thetas, wheels and prisms as induced subgraphs, and one for graphs with no thetas, wheels and pyramids as induced subgraphs. A consequence is a polynomial time recognition algorithms for these two classes.

  19. TangiWheel: A widget for manipulating collections on tabletop displays supporting hybrid Input modality

    OpenAIRE

    Catalá Bolós, Alejandro; García Sanjuan, Fernando; Jaén Martínez, Francisco Javier; Mocholi Agües, Jose Antonio

    2012-01-01

    In this paper we present TangiWheel, a collection manipulation widget for tabletop displays. Our implementation is flexible, allowing either multi-touch or interaction, or even a hybrid scheme to better suit user choice and convenience. Different TangiWheel aspects and features are compared with other existing widgets for collection manipulation. The study reveals that TangiWheel is the first proposal to support a hybrid input modality with large resemblance levels between touch and tangible ...

  20. Dynamic Research of the Flexible Wheel of a Double Harmonic Gear Transmission

    Directory of Open Access Journals (Sweden)

    Draghita Ianici

    2015-07-01

    Full Text Available The paper presents the results of a dynamic research of the flexible wheel of the double harmonic gear transmission, by determining the state of strain and stress of its wall, in cases the wheel is deformed by a mechanical waves generator with: two rolls, two eccentric discs and cam. The dynamic research involves modelling and the numerical simulation of flexible wheel, by using the finite element method, with the help of SolidWorks Simulation program in elastic range.

  1. ANALYSIS OF LATERAL VIBRATION OF THE WHEEL RELATIVE TO THE RAIL WITH VIDEO

    Directory of Open Access Journals (Sweden)

    V. O. Melnychuk

    2010-03-01

    Full Text Available In the article the videotape recordings of wheel motion on rail track, done during the dynamic tests of carriages, are analyzed. The treatment includes fixing of wheel rim positions in relation to a rail, construction of the spline function of displacement and its frequency description. The purpose of analysis is to determine the presence of harmonic components in the transversal wheel displacements.

  2. The Structure of Wheel Check Valve Influence on Air Block Phenomenon of Piezoelectric Micro-Pump

    OpenAIRE

    Song Chen; Yong Liu; Yanhu Shen; Jiantao Wang; Zhigang Yang

    2015-01-01

    To improve the stability and reliability of the piezoelectric micro-pump, the cause of air block phenomenon is analyzed on the structure of wheel check valve. During the movement of the bubble in the micro-channel, pressure drop occurs, the main factor which influences the bubble going through is opening height of the wheel check valve. Five groups of wheel check valves with different structures are used to test the wheel check valve opening height and air block probability. The experiment re...

  3. Reaction Wheel Friction Telemetry Data Processing Methodology and On-Orbit Experience

    Science.gov (United States)

    Hacker, Johannes M.; Ying, Jiongyu; Lai, Peter C.

    2015-09-01

    A Globalstar 2nd generation satellite experienced a reaction wheel mechanical failure, and in response Globalstar has been closely monitoring reaction wheel bearing friction. To prevent another reaction wheel hardware failure and subsequent shortened satellite mission life, a friction data processing methodology was developed as an on-orbit monitoring tool for the ground to issue early warning and take appropriate action on any hardware degradation or potential failure. The methodology, reaction wheel friction behavior, and its application to an on-orbit anomaly experience will be presented.

  4. Simulation analysis of grinding wheel motion trajectory on SiC ceramics aspheric surface grinding

    Science.gov (United States)

    Zhang, Feihu; Liu, Lifei; Li, Chunhui

    2014-08-01

    In grinding process of SiC ceramics aspheric surface, the motion trajectory of grinding wheel has great influence on the surface forming. The paper provides mathematical models of grinding wheel movements; analytical simulation was done to describe the trajectories of the grinding wheel in manufacturing an aspherical workpiece. The effect of grinding parameters (including the rotation speed of the workpiece, the feed rate of grinding wheel etc.) on the aspheric surface coverage rate was conducted and discussed in detail. An experimental study was done according to the simulation results and an aspheric surface with form error less than 10μm was gained.

  5. A comparing design of satellite attitude control system based on reaction wheel

    Institute of Scientific and Technical Information of China (English)

    CHENG Hao; GE Sheng-min; SHEN Yi

    2008-01-01

    The disturbance caused by the reaction wheel with a current controller greatly influences the accuracy and stability of the satellite attitude control system.To solve this problem,the idea of speed feedback compensation control reaction wheel is put forward.This paper introduces the comparison on design and performance of two satellite attitude control systems,which are separately based on the current control reaction wheel and the speed feedback compensation control reaction wheel.Analysis shows that the speed feedback compensation control flywheel system may effectively suppress the torque fluctuation.Simulation results indicate that the satellite attitude control system with the speed feedback compensation control flywheel has improved performance.

  6. STM manipulation of a subphthalocyanine double-wheel molecule on Au(111)

    International Nuclear Information System (INIS)

    A new class of double-wheel molecules is manipulated on a Au(111) surface by the tip of a scanning tunneling microscope (STM) at low temperature. The double-wheel molecule consists of two subphthalocyanine wheels connected by a central rotation carbon axis. Each of the subphthalocyanine wheels has a nitrogen tag to monitor its intramolecular rolling during an STM manipulation sequence. The position of the tag can be followed by STM, allowing us to distinguish between the different lateral movements of the molecule on the surface when manipulated by the STM tip.

  7. Position and force control of a vehicle with two or more steerable drive wheels

    Energy Technology Data Exchange (ETDEWEB)

    Reister, D.B.; Unseren, M.A.

    1992-10-01

    When a vehicle with two or more steerable drive wheels is traveling in a circle, the motion of the wheels is constrained. The wheel translational velocity divided by the radius to the center of rotation must be the same for all wheels. When the drive wheels are controlled independently using position control, the motion of the wheels may violate the constraints and the wheels may slip. Consequently, substantial errors can occur in the orientation of the vehicle. A vehicle with N drive wheels has (N - 1) constraints and one degree of freedom. We have developed a new approach to the control of a vehicle with N steerable drive wheels. The novel aspect of our approach is the use of force control. To control the vehicle, we have one degree of freedom for the position on the circle and (N - 1) forces that can be used to reduce errors. Recently, Kankaanranta and Koivo developed a control architecture that allows the force and position degrees of freedom to be decoupled. In the work of Kankaanranta and Koivo the force is an exogenous input. We have made the force endogenous by defining the force in terms of the errors in satisfying the rigid body kinematic constraints. We have applied the control architecture to the HERMIES-III robot and have measured a dramatic reduction in error (more than a factor of 20) compared to motions without force control.

  8. Process Modeling of Low-Pressure Die Casting of Aluminum Alloy Automotive Wheels

    Science.gov (United States)

    Reilly, C.; Duan, J.; Yao, L.; Maijer, D. M.; Cockcroft, S. L.

    2013-09-01

    Although on initial inspection, the aluminum alloy automotive wheel seems to be a relatively simple component to cast based on its shape, further insight reveals that this is not the case. Automotive wheels are in a select group of cast components that have strict specifications for both mechanical and aesthetic characteristics due to their important structural requirements and their visibility on a vehicle. The modern aluminum alloy automotive wheel continues to experience tightened tolerances relating to defects to improve mechanical performance and/or the physical appearance. Automotive aluminum alloy wheels are assessed against three main criteria: wheel cosmetics, mechanical performance, and air tightness. Failure to achieve the required standards in any one of these categories will lead to the wheel either requiring costly repair or being rejected and remelted. Manufacturers are becoming more reliant on computational process modeling as a design tool for the wheel casting process. This article discusses and details examples of the use of computational process modeling as a predictive tool to optimize the casting process from the standpoint of defect minimization with the emphasis on those defects that lead to failure of aluminum automotive wheels, namely, macroporosity, microporosity, and oxide films. The current state of applied computational process modeling and its limitations with regard to wheel casting are discussed.

  9. Fatigue Property of Low Cost and High Strength Wheel Steel for Commercial Vehicle

    Institute of Scientific and Technical Information of China (English)

    WANG Ning; LI Yi; DU Lin-xiu; WU Di; LIU Xiang-hua

    2009-01-01

    The fatigue properties of the newly developed wheel steel used for commercial vehicles were studied using push-pull axial loading fatigue tests with stress ratio R=-1. Q235B steel, which is conventionally applied to commercial vehicle wheels, was also analyzed for comparison. Although the chemical composition and microstructure(ferrite and pearlite) of newly developed wheel steel were similar to those of Q235B, the 107 cycles fatigue limit of the new wheel steel was 260 MPa, which is 24% higher than that of Q235B (210 MPa). The improvement of the fatigue strength of the new wheel steel can be attributed to grain refinement. In order to investigate the effect of the decrease in thickness of the wheel steel on the fatigue property of the wheel, dynamic cornering fatigue tests were conducted on full scale wheels with the model of 8. 25×22.5. The results indicated that the newly developed wheel steel had outstanding fatigue life even if the mass loss was 10% in comparison with Q235B.

  10. Big Bang–Big Crunch Optimization Algorithm for Linear Phase Fir Digital Filter Design

    OpenAIRE

    Ms. Rashmi Singh Dr. H. K. Verma

    2012-01-01

    The Big Bang–Big Crunch (BB–BC) optimization algorithm is a new optimization method that relies on the Big Bang and Big Crunch theory, one of the theories of the evolution of the universe. In this paper, a Big Bang–Big Crunch algorithm has been used here for the design of linear phase finite impulse response (FIR) filters. Here the experimented fitness function based on the mean squared error between the actual and the ideal filter response. This paper presents the plot of magnitude response ...

  11. New Record Five-Wheel Drive, Spirit's Sol 1856 (Stereo)

    Science.gov (United States)

    2009-01-01

    [figure removed for brevity, see original site] Left-eye view of a color stereo pair for PIA11962 [figure removed for brevity, see original site] Right-eye view of a color stereo pair for PIA11962 NASA's Mars Exploration Rover Spirit used its navigation camera to take the images that have been combined into this stereo, 180-degree view of the rover's surroundings during the 1,856th Martian day, or sol, of Spirit's surface mission (March 23, 2009). The center of the view is toward the west-southwest. This view combines images from the left-eye and right-eye sides of the navigation camera. It appears three-dimensional when viewed through red-blue glasses with the red lens on the left. The rover had driven 25.82 meters (84.7 feet) west-northwestward earlier on Sol 1856. This is the longest drive on Mars so far by a rover using only five wheels. Spirit lost the use of its right-front wheel in March 2006. Before Sol 1856, the farthest Spirit had covered in a single sol's five-wheel drive was 24.83 meters (81.5 feet), on Sol 1363 (Nov. 3, 2007). The Sol 1856 drive made progress on a route planned for taking Spirit around the western side of the low plateau called 'Home Plate.' A portion of the northwestern edge of Home Plate is prominent in the left quarter of this image, toward the south. This view is presented as a cylindrical-perspective projection with geometric seam correction.

  12. Wheel torque control for a rough terrain rover

    OpenAIRE

    Lamon, Pierre; Krebs, Ambroise; Lauria, Michel; Siegwart, Roland,; Shooter, Steven

    2004-01-01

    Navigating in rough terrain is a complex task that requires the robot to be considered as a holistic system. Algorithms, which don’t consider the physical dimensions and capabilities of the mobile robot lead to inefficient motion and suffer from a lack of robustness. A physical model of the robot is necessary for trajectory control. In this paper, quasi-static modeling of a six-wheeled robot with a passive suspension mechanism is presented together with a method for selecting the optima...

  13. The Read Out Controller for the ATLAS New Small Wheel

    CERN Document Server

    Coliban, Radu Mihai; The ATLAS collaboration; Tulbure, Traian Tiberiu; Martoiu, Victor Sorin; Levinson, Lorne; Vermeulen, Jos

    2016-01-01

    In the context of the New Small Wheel data path, we designed the Read Out Controller (ROC) ASIC for handling, preprocessing and formatting the data generated by the NSW VMM upstream chips. The ROC will concentrate the data streams from 8VMMs, filter data based on the BCID and transmit the data to FELIX via the L1DDC. ROC is composed of 8 VMM Capture modules, a cross-bar and 4 SubROC modules. The output data is sent via 4 high-speed e-links.

  14. Three-wheeled scooter taxi: A safety analysis

    Indian Academy of Sciences (India)

    S Mukherjee; D Mohan; T R Gawade

    2007-08-01

    The rollover propensity of a three-wheeled scooter taxi used extensively on SE Asian roads is analysed in this report. A rigid body mathematical model was used to simulate increasing steer, NHTSA -turn, and Road Edge Recovery maneuvers. The anomaly between public perception of the rollover susceptibility and available crash data has been resolved through finite element (FE) simulation. The optimum configuration of the vehicle and seating arrangement for varying numbers of passengers was determined. The safety of occupants and pedestrians in impact events was analysed through simulation in MADYMOTM, and cost effective solutions to improve safety were identified.

  15. Reaction Wheel Control Design Using Linear Quadratic Controller

    Science.gov (United States)

    Nubli Muhamad, Nur; Susanto, Erwin; Syihabuddin, Budi; Prasetya Dwi Wibawa, Ig.

    2016-01-01

    This paper studies the design of active attitude control system of a nanosatellite in a single axis. In this paper, we consider dc motor based reaction wheel as an actuator, because of its pointing accuracy. However, the power consumption of the dc motor is often relatively large and needed to be optimized. Linear quadratic controller is supposed to have an ability to minimize power consumption and able to enhance the system performance. To show the advantage of this method, simulation result of attitude response, state trajectory, and trajectory of DC motor voltage are presented.

  16. MOBILITY EVALUATION AND INNOVATION OF WHEELED SPACE ROVER

    Institute of Scientific and Technical Information of China (English)

    SHANG Jianzhong; LUO Zirong; LI Shengyi; TANG Li

    2006-01-01

    The mission and function requirements of lunar rover are analyzed, based on virtual prototype technology, the mobility evaluation theory and method for wheeled space rover are proposed,which provide a new way to study the innovative design of lunar rover. Based on the above theoretical system, an innovative lunar rover suspension system, which adopts a two-crank-slider mechanism, is proposed, and its dynamics model is created. Adopting virtual prototype technology, the ground adaptability, over-obstacle ability and driving placidity of the rover are evaluated in the virtual prototype software ADAMS. The analysis results show that the rover provides a high degree of mobility.

  17. A Localisation and Navigation System for an Autonomous Wheel Loader

    OpenAIRE

    Lilja, Robin

    2011-01-01

    Autonomous vehicles are an emerging trend in robotics, seen in a vast range of applications and environments. Consequently, Volvo Construction Equipment endeavour to apply the concept of autonomous vehicles onto one of their main products. In the company’s Autonomous Machine project an autonomous wheel loader is being developed. As an ob jective given by the company; a demonstration proving the possibility of conducting a fully autonomous load and haul cycle should be performed. Conducting su...

  18. Verification hybrid control of a wheeled mobile robot and manipulator

    Science.gov (United States)

    Muszynska, Magdalena; Burghardt, Andrzej; Kurc, Krzysztof; Szybicki, Dariusz

    2016-04-01

    In this article, innovative approaches to realization of the wheeled mobile robots and manipulator tracking are presented. Conceptions include application of the neural-fuzzy systems to compensation of the controlled system's nonlinearities in the tracking control task. Proposed control algorithms work on-line, contain structure, that adapt to the changeable work conditions of the controlled systems, and do not require the preliminary learning. The algorithm was verification on the real object which was a Scorbot - ER 4pc robotic manipulator and a Pioneer - 2DX mobile robot.

  19. Rollover Dynamics of a Narrow Tilting Three-Wheeled Vehicle

    Directory of Open Access Journals (Sweden)

    Jubin Antony J

    2016-01-01

    Full Text Available A narrow-track vehicle possesses many advantages like fuel efficiency and reduced road footprint among others. But the main drawback of this model stems from the fact that they tend to rollover more easily due to their narrow base area. In order to overcome this rollover instability, these vehicles are made to tilt to obtain increased virtual base area. The focus of this paper is to analyse the minimum lean angle necessary for a narrow three-wheeled vehicle under lateral acceleration to negotiate a curve safely. In addition, the influence of the horizontal positions of the centre of mass of the vehicle over the rollover speeds is studied.

  20. Tractive performance analysis of diameter-variable wheel for 4WD all-terrain vehicle on soft soil%四驱全地形车可变直径轮软土牵引特性分析

    Institute of Scientific and Technical Information of China (English)

    陈新波; 高峰; 徐国艳; 药晓江

    2012-01-01

    为解决常规地面车辆及传统车轮在沙地、滩涂等松软地域行驶或作业时存在通过性差、效率低、能耗大甚至无法行驶的问题,自主创新设计出四驱可变直径轮轻型全地形探测车,车轮具有可张开成为弹性步行轮和合拢成为刚性圆车轮2种工作轮态.基于贝克模型的经典地面力学理论,分别建立了可变直径轮张开轮及合拢轮态时与3种典型松软沙土交互作用关系的力学简化模型,计算并对比分析了可变直径轮两种工作轮态的挂钩牵引力和驱动力矩、牵引效率等随滑转率的变化关系及车轮接近角与沉陷量关系.结果表明车轮的挂钩牵引力、驱动力矩和牵引效率等均受到车轮滑转率及软土特性参数的制约,在松软路面上可变直径轮张开步行轮比合拢圆轮能产生更大的挂钩牵引力、驱动力矩、牵引效率和更小的沉陷量,更有利于提高车轮的软土牵引通过性.分析结果可作为后续实验研究对比的参考.%Four-wheel drive all-terrain light exploration vehicle with diameter-variable wheels was innova tively designed out to solve the problems when conventional ground vehicles and wheels driving on soft terrain, such as poor traffieability, low efficiency, big energy consumption and even can't drive. The wheel has two ex treme working status: elastic extended walking-wheel and folded rigid wheel. Based on classical terrameehan ies theory, the dynamics models of interactions between two types of working wheel status and three kinds of typical soft soils were established. The drawbar pull, driving torque and driving efficiency as well as sinkage of diameter-variable wheel were analyzed under the condition of different slip. The results indicate that traction trafficability indexes are limited by wheel slip and soft soil parameters. The simulation provides theoretical ba sis for that the elastic extended wheel can improve significantly

  1. An Overview of Big Data Privacy Issues

    OpenAIRE

    Patrick Hung

    2013-01-01

    Big data is the term for a collection of large and complex datasets from different sources that is difficult to process using traditional data management and processing applications. In these datasets, some information must be kept secret from others. On the other hand, some information has to be released for acquainting information or big data analytical services. The research challenge is how to protect the private information in the context of big data. Privacy is described by the ability ...

  2. Social Big Data and Privacy Awareness

    OpenAIRE

    Sang, Lin

    2015-01-01

    Based on the rapid development of Big Data, the data from the online social network becomea major part of it. Big data make the social networks became data-oriented rather than social-oriented. Taking this into account, this dissertation presents a qualitative study to research howdoes the data-oriented social network affect its users’ privacy management for nowadays. Within this dissertation, an overview of Big Data and privacy issues on the social network waspresented as a background study. ...

  3. EAARL-B Topography-Big Thicket National Preserve: Big Sandy Creek Corridor Unit, Texas, 2014

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A first-surface topography Digital Elevation Model (DEM) mosaic for the Big Sandy Creek Corridor Unit of Big Thicket National Preserve in Texas was produced from...

  4. EAARL-B Topography-Big Thicket National Preserve: Big Sandy Creek Unit, Texas, 2014

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A bare-earth topography digital elevation model (DEM) mosaic for the Big Sandy Creek Unit of Big Thicket National Preserve in Texas, was produced from remotely...

  5. EAARL-B Topography-Big Thicket National Preserve: Big Sandy Creek Unit, Texas, 2014

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A first-surface topography digital elevation model (DEM) mosaic for the Big Sandy Creek Unit of Big Thicket National Preserve in Texas, was produced from remotely...

  6. EAARL-B Topography-Big Thicket National Preserve: Big Sandy Creek Corridor Unit, Texas, 2014

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A bare-earth topography Digital Elevation Model (DEM) mosaic for the Big Sandy Creek Corridor Unit of Big Thicket National Preserve in Texas was produced from...

  7. Fitting ERGMs on big networks.

    Science.gov (United States)

    An, Weihua

    2016-09-01

    The exponential random graph model (ERGM) has become a valuable tool for modeling social networks. In particular, ERGM provides great flexibility to account for both covariates effects on tie formations and endogenous network formation processes. However, there are both conceptual and computational issues for fitting ERGMs on big networks. This paper describes a framework and a series of methods (based on existent algorithms) to address these issues. It also outlines the advantages and disadvantages of the methods and the conditions to which they are most applicable. Selected methods are illustrated through examples. PMID:27480375

  8. Big deformation in 17C

    International Nuclear Information System (INIS)

    Reaction and interaction cross sections of 17C on a carbon target have been re-analyzed using the modified Glauber model. The analysis with a deformed Woods-Saxon density/potential suggests a big deformation structure for 17C. The existence of a tail in the density distribution supports the possibility of it being a one-neutron halo structure. Under a deformed core plus a single-particle assumption, analysis shows a dominant d-wave of the valence neutron in 17C. (authors)

  9. Big bang nucleosynthesis: An update

    International Nuclear Information System (INIS)

    An update on the standard model of big bang nucleosynthesis (BBN) is presented. With the value of the baryon-tophoton ratio determined to high precision by WMAP, standard BBN is a parameter-free theory. In this context, the theoretical prediction for the abundances of D, 4He, and 7Li is discussed and compared to their observational determination. While concordance for D and 4He is satisfactory, the prediction for 7Li exceeds the observational determination by a factor of about four. Possible solutions to this problem are discussed

  10. Big Five -persoonallisuuspiirteiden yhteydet unettomuuteen

    OpenAIRE

    Aronen, Aino

    2015-01-01

    Tutkimuksen tarkoituksena oli selvittÀÀ, ovatko Big Five -persoonallisuuspiirteet (neuroottisuus, ulospÀinsuuntautuneisuus, tunnollisuus, avoimuus kokemuksille ja sovinnollisuus) yhteydessÀ unettomuuden oireisiin, joita olivat nukahtamisvaikeudet, herÀilyt, vaikeudet pysyÀ unessa ja vÀsyneenÀ herÀÀmiset normaalipituisten unien jÀlkeen. Unettomuutta koskevien teorioiden mukaan korkea neuroottisuus, matala ulospÀinsuuntautuneisuus, matala tunnollisuus ja matala sovinnollisuus voivat...

  11. Traffic information computing platform for big data

    International Nuclear Information System (INIS)

    Big data environment create data conditions for improving the quality of traffic information service. The target of this article is to construct a traffic information computing platform for big data environment. Through in-depth analysis the connotation and technology characteristics of big data and traffic information service, a distributed traffic atomic information computing platform architecture is proposed. Under the big data environment, this type of traffic atomic information computing architecture helps to guarantee the traffic safety and efficient operation, more intelligent and personalized traffic information service can be used for the traffic information users

  12. Big Data Analytics Using Cloud and Crowd

    OpenAIRE

    Allahbakhsh, Mohammad; Arbabi, Saeed; Motahari-Nezhad, Hamid-Reza; Benatallah, Boualem

    2016-01-01

    The increasing application of social and human-enabled systems in people's daily life from one side and from the other side the fast growth of mobile and smart phones technologies have resulted in generating tremendous amount of data, also referred to as big data, and a need for analyzing these data, i.e., big data analytics. Recently a trend has emerged to incorporate human computing power into big data analytics to solve some shortcomings of existing big data analytics such as dealing with ...

  13. Big data optimization recent developments and challenges

    CERN Document Server

    2016-01-01

    The main objective of this book is to provide the necessary background to work with big data by introducing some novel optimization algorithms and codes capable of working in the big data setting as well as introducing some applications in big data optimization for both academics and practitioners interested, and to benefit society, industry, academia, and government. Presenting applications in a variety of industries, this book will be useful for the researchers aiming to analyses large scale data. Several optimization algorithms for big data including convergent parallel algorithms, limited memory bundle algorithm, diagonal bundle method, convergent parallel algorithms, network analytics, and many more have been explored in this book.

  14. Big data: an introduction for librarians.

    Science.gov (United States)

    Hoy, Matthew B

    2014-01-01

    Modern life produces data at an astounding rate and shows no signs of slowing. This has lead to new advances in data storage and analysis and the concept of "big data," that is, massive data sets that can yield surprising insights when analyzed. This column will briefly describe what big data is and why it is important. It will also briefly explore the possibilities and problems of big data and the implications it has for librarians. A list of big data projects and resources is also included. PMID:25023020

  15. Big data analytics with R and Hadoop

    CERN Document Server

    Prajapati, Vignesh

    2013-01-01

    Big Data Analytics with R and Hadoop is a tutorial style book that focuses on all the powerful big data tasks that can be achieved by integrating R and Hadoop.This book is ideal for R developers who are looking for a way to perform big data analytics with Hadoop. This book is also aimed at those who know Hadoop and want to build some intelligent applications over Big data with R packages. It would be helpful if readers have basic knowledge of R.

  16. Urgent Call for Nursing Big Data.

    Science.gov (United States)

    Delaney, Connie W

    2016-01-01

    The purpose of this panel is to expand internationally a National Action Plan for sharable and comparable nursing data for quality improvement and big data science. There is an urgent need to assure that nursing has sharable and comparable data for quality improvement and big data science. A national collaborative - Nursing Knowledge and Big Data Science includes multi-stakeholder groups focused on a National Action Plan toward implementing and using sharable and comparable nursing big data. Panelists will share accomplishments and future plans with an eye toward international collaboration. This presentation is suitable for any audience attending the NI2016 conference. PMID:27332330

  17. Traffic information computing platform for big data

    Energy Technology Data Exchange (ETDEWEB)

    Duan, Zongtao, E-mail: ztduan@chd.edu.cn; Li, Ying, E-mail: ztduan@chd.edu.cn; Zheng, Xibin, E-mail: ztduan@chd.edu.cn; Liu, Yan, E-mail: ztduan@chd.edu.cn; Dai, Jiting, E-mail: ztduan@chd.edu.cn; Kang, Jun, E-mail: ztduan@chd.edu.cn [Chang' an University School of Information Engineering, Xi' an, China and Shaanxi Engineering and Technical Research Center for Road and Traffic Detection, Xi' an (China)

    2014-10-06

    Big data environment create data conditions for improving the quality of traffic information service. The target of this article is to construct a traffic information computing platform for big data environment. Through in-depth analysis the connotation and technology characteristics of big data and traffic information service, a distributed traffic atomic information computing platform architecture is proposed. Under the big data environment, this type of traffic atomic information computing architecture helps to guarantee the traffic safety and efficient operation, more intelligent and personalized traffic information service can be used for the traffic information users.

  18. BigDataBench: a Big Data Benchmark Suite from Internet Services

    OpenAIRE

    Wang, Lei; Zhan, Jianfeng; Luo, Chunjie; Zhu, Yuqing; Yang, Qiang; He, Yongqiang; Gao, Wanling; Jia, Zhen; Shi, Yingjie; Zhang, Shujie; Zheng, Chen; Lu, Gang; Zhan, Kent; Li, Xiaona; Qiu, Bizhu

    2014-01-01

    As architecture, systems, and data management communities pay greater attention to innovative big data systems and architectures, the pressure of benchmarking and evaluating these systems rises. Considering the broad use of big data systems, big data benchmarks must include diversity of data and workloads. Most of the state-of-the-art big data benchmarking efforts target evaluating specific types of applications or system software stacks, and hence they are not qualified for serving the purpo...

  19. Big Data; A Management Revolution : The emerging role of big data in businesses

    OpenAIRE

    Blasiak, Kevin

    2014-01-01

    Big data is a term that was coined in 2012 and has since then emerged to one of the top trends in business and technology. Big data is an agglomeration of different technologies resulting in data processing capabilities that have been unreached before. Big data is generally characterized by 4 factors. Volume, velocity and variety. These three factors distinct it from the traditional data use. The possibilities to utilize this technology are vast. Big data technology has touch points in differ...

  20. CloudJet4BigData: Streamlining Big Data via an accelerated socket interface

    OpenAIRE

    Frank Z.Wang

    2014-01-01

    Big data needs to feed users with fresh processing results and cloud platforms can be used to speed up big data applications. This paper describes a new data communication protocol (CloudJet) for long distance and large volume big data accessing operations to alleviate the large latencies encountered in sharing big data resources in the clouds. It encapsulates a dynamic multi-stream/multi-path engine at the socket level, which conforms to Portable Operating System Interface (POSIX) and thereb...